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Gongora K, Vankerschaver J, Sampers I, Van Haute S. The influence of pH on the efficacy of oxidation-reduction potential (ORP) to predict chlorine disinfection of surrogate bacteria, Escherichia coli O157:H7 and Listeria monocytogenes in oxidant demand free conditions and fresh produce wash water. Food Microbiol 2024; 121:104516. [PMID: 38637078 DOI: 10.1016/j.fm.2024.104516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 04/20/2024]
Abstract
Oxidation-reduction potential (ORP) is commonly used as a rapid measurement of the antimicrobial potential of free chlorine during industrial fresh produce washing. The current study tested the hypothesis that ORP can act as a "single variable" measurement of bacterial (vegetative and endospores) inactivation effectiveness with free chlorine irrespective of the water pH value. This situation has on occasion been assumed but never confirmed nor disproven. Chlorine-dosed pH 6.5 and 8.5 phosphate buffer solutions were inoculated with Escherichia coli (E. coli), Listeria innocua (L. innocua), or Bacillus subtilis (B. subtilis) endospores. ORP, free chlorine (FC), and log reduction were monitored after 5 s (for E. coli and L. innocua) and up to 30 min (for B. subtilis spores) of disinfection. Logistic and exponential models were developed to describe how bacteria reduction varied as a function of ORP at different pH levels. Validation tests were performed in phosphate buffered pH 6.5 and 8.5 cabbage wash water periodically dosed with FC, cabbage extract and a cocktail of Escherichia coli O157:H7 (E. coli O157:H7) and Listeria monocytogenes (L. monocytogenes). The built logistic and exponential models confirmed that at equal ORP values, the inactivation of the surrogate strains was not consistent across pH 6.5 and pH 8.5, with higher reductions at higher pH. This is the opposite of the well-known free chlorine-controlled bacterial inactivation, where the antibacterial effect is higher at lower pH. The validation test results indicated that in the cabbage wash water, the relationship between disinfection efficiency and ORP was consistent with the oxidant demand free systems. The study suggests that ORP cannot serve as a reliable single variable measurement to predict bacterial disinfection in buffered systems. When using ORP to monitor and control the antibacterial effectiveness of the chlorinated wash water, it is crucial to take into account (and control) the pH.
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Affiliation(s)
- Kimberly Gongora
- Laboratory of Food Microbiology and Biotechnology, Department of Food Technology, Safety and Health, Ghent University, 9000, Ghent, Belgium; Center for Food Biotechnology and Microbiology, Ghent University Global Campus, Incheon, 21985, South Korea
| | - Joris Vankerschaver
- Center for Biosystems and Biotech Data Science, Ghent University Global Campus, Incheon, 21985, South Korea; Department of Applied Mathematics, Computer Science and Statistics, Ghent University, 9000, Ghent, Belgium
| | - Imca Sampers
- Laboratory of Food Microbiology and Biotechnology, Department of Food Technology, Safety and Health, Ghent University, 9000, Ghent, Belgium; Research Unit VEG-i-TEC, Department of Food Technology, Safety and Health, Ghent University, Campus Kortrijk, Sint-Martens-Latemlaan 2B, 8500, Kortrijk, Belgium
| | - Sam Van Haute
- Laboratory of Food Microbiology and Biotechnology, Department of Food Technology, Safety and Health, Ghent University, 9000, Ghent, Belgium; Center for Food Biotechnology and Microbiology, Ghent University Global Campus, Incheon, 21985, South Korea.
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Luo L, Wang Z, Huang X, Gu JD, Yu C, Deng O. The fate of antibiotic resistance genes in wastewater containing microalgae treated by chlorination, ultra-violet, and Fenton reaction. Water Res 2024; 254:121392. [PMID: 38430757 DOI: 10.1016/j.watres.2024.121392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/21/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Abstract
Antibiotic resistance genes (ARGs) and bacteria (ARBs) in the effluent of wastewater treatment plants (WWTPs) are of utmost importance for the dissemination of ARGs in natural aquatic environments. Therefore, there is an urgent need for effective technologies to eliminate WWTP ARGs/ARBs and mitigate the associated risks posed by the discharged ARG in aquatic environments. To test the effective technology for eliminating ARGs/ARBs, we compared the removal of ARGs and ARBs by three different tertiary treatments, namely ultra-violet (UV) disinfection, chlorination disinfection, and Fenton oxidation. Then, the treated wastewater was co-cultured with Chlorella vulgaris (representative of aquatic biota) to investigate the fate of discharged ARGs into the aquatic environment. The results demonstrated that chlorination (at a chlorine concentration of 15 mg/L) and Fenton (at pH 2.73, with 0.005 mol/L Fe2+ and 0.0025 mol/L H2O2) treatment showed higher efficacy in ARG removal (1.8 - 4.17 logs) than UV treatment (15 min) (1.29 - 3.87 logs). Moreover, chlorine at 15 mg/L and Fenton treatment effectively suppressed ARB regeneration while UV treatment for 15 min could not. Regardless of treatments tested in this study, the input of treated wastewater to the Chlorella system increased the number of ARGs and mobile genetic elements (MGEs), indicating the potential risk of ARG dissemination associated with WWTP discharge. Among the wastewater-Chlorella co-culture systems, chlorination resulted in less of an increase in the number of ARGs and MGEs compared to Fenton and UV treatment. When comparing the wastewater systems to the co-culture systems, it was observed that Chlorella vulgaris reduced the number of ARGs and MGEs in chlorination and UV-treated wastewater; however, Chlorella vulgaris promoted ARG survival in Fenton-treated water, suggesting that aquatic microalgae might act as a barrier to ARG dissemination. Overall, chlorination treatment not only effectively removes ARGs and inhibits ARB regeneration but also shows a lower risk of ARG dissemination. Therefore, chlorination is recommended for practical application in controlling the spread of discharged ARGs from WWTP effluent in natural aquatic environments.
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Affiliation(s)
- Ling Luo
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, PR China.
| | - Zimu Wang
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, PR China
| | - Xin Huang
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, PR China
| | - Ji-Dong Gu
- Environmental Science and Engineering Research Group, Guangdong Technion - Israel Institute of Technology, Shantou 515063, PR China
| | - Chenxiao Yu
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, PR China
| | - Ouping Deng
- College of Environmental Sciences, Sichuan Agricultural University, Chengdu 611130, PR China; College of Resources, Sichuan Agricultural University, Chengdu 611130, PR China.
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Zhang M, Leong MW, Mitch WA, Blish CA, Boehm A. Persistence and free chlorine disinfection of human coronaviruses and their surrogates in water. Appl Environ Microbiol 2024; 90:e0005524. [PMID: 38511945 PMCID: PMC11022552 DOI: 10.1128/aem.00055-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
The coronavirus disease 2019 pandemic illustrates the importance of understanding the behavior and control of human pathogenic viruses in the environment. Exposure via water (drinking, bathing, and recreation) is a known route of transmission of viruses to humans, but the literature is relatively void of studies on the persistence of many viruses, especially coronaviruses, in water and their susceptibility to chlorine disinfection. To fill that knowledge gap, we evaluated the persistence and free chlorine disinfection of human coronavirus OC43 (HCoV-OC43) and its surrogates, murine hepatitis virus (MHV) and porcine transmissible gastroenteritis virus (TGEV), in drinking water and laboratory buffer using cell culture methods. The decay rate constants of human coronavirus and its surrogates in water varied, depending on virus and water matrix. In drinking water without disinfectant addition, MHV showed the largest decay rate constant (estimate ± standard error, 2.25 ± 0.09 day-1) followed by HCoV-OC43 (0.99 ± 0.12 day-1) and TGEV (0.65 ± 0.06 day-1), while in phosphate buffer without disinfectant addition, HCoV-OC43 (0.51 ± 0.10 day-1) had a larger decay rate constant than MHV (0.28 ± 0.03 day-1) and TGEV (0.24 ± 0.02 day-1). Upon free chlorine disinfection, the inactivation rates of coronaviruses were independent of free chlorine concentration and were not affected by water matrix, though they still varied between viruses. TGEV showed the highest susceptibility to free chlorine disinfection with the inactivation rate constant of 113.50 ± 7.50 mg-1 min-1 L, followed by MHV (81.33 ± 4.90 mg-1 min-1 L) and HCoV-OC43 (59.42 ± 4.41 mg-1 min-1 L). IMPORTANCE This study addresses an important knowledge gap on enveloped virus persistence and disinfection in water. Results have immediate practical applications for shaping evidence-based water policies, particularly in the development of disinfection strategies for pathogenic virus control.
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Affiliation(s)
- Mengyang Zhang
- Department of Civil and Environmental Engineering, School of Engineering and Doerr School of Sustainability, Stanford University, Stanford, California, USA
| | - Michelle Wei Leong
- Department of Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - William A. Mitch
- Department of Civil and Environmental Engineering, School of Engineering and Doerr School of Sustainability, Stanford University, Stanford, California, USA
| | - Catherine A. Blish
- Department of Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Alexandria Boehm
- Department of Civil and Environmental Engineering, School of Engineering and Doerr School of Sustainability, Stanford University, Stanford, California, USA
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Sun H, Zhou ZJ, Wen HQ, Chen FF, Pan Y, Tang Q, Yu HQ. Deciphering the Roles of Extracellular Polymeric Substances (EPS) in Shaping Disinfection Kinetics through Permanent Removal via Genetic Disruption. Environ Sci Technol 2024; 58:6552-6563. [PMID: 38571383 DOI: 10.1021/acs.est.4c01612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
Extracellular polymeric substances (EPS) ubiquitously encapsulate microbes and play crucial roles in various environmental processes. However, understanding their complex interactions with dynamic bacterial behaviors, especially during the disinfection process, remains very limited. In this work, we investigated the impact of EPS on bacterial disinfection kinetics by developing a permanent EPS removal strategy. We genetically disrupted the synthesis of exopolysaccharides, the structural components of EPS, in Pseudomonas aeruginosa, a well-known EPS-producing opportunistic pathogen found in diverse environments, creating an EPS-deficient strain. This method ensured a lasting absence of EPS while maintaining bacterial integrity and viability, allowing for real-time in situ investigations of the roles of EPS in disinfection. Our findings indicate that removing EPS from bacteria substantially lowered their susceptibility threshold to disinfectants such as ozone, chloramine B, and free chlorine. This removal also substantially accelerated disinfection kinetics, shortened the resistance time, and increased disinfection efficiency, thereby enhancing the overall bactericidal effect. The absence of EPS was found to enhance bacterial motility and increase bacterial cell vulnerability to disinfectants, resulting in greater membrane damage and intensified reactive oxygen species (ROS) production upon exposure to disinfectants. These insights highlight the central role of EPS in bacterial defenses and offer promising implications for developing more effective disinfection strategies.
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Hayatimehr S, Mirkalantari S, Amirmozafari N, Jazi FM, Moghadam MT. Virulence Genes and Biofilm Formation Among Legionella pneumophila Isolates Collected from Hospital Water Sources. Curr Microbiol 2024; 81:141. [PMID: 38625380 DOI: 10.1007/s00284-023-03609-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 12/29/2023] [Indexed: 04/17/2024]
Abstract
Legionella pneumophila can be transmitted to people, especially immunocompromised patients, via hospital water pipe systems and cause severe pneumonia. The aim of our study was to investigate the presence of major virulence factor genes, ability of biofilms formation, and correlation between presence of Legionella isolates and temperature, pH, and residual chlorine of water. Hundred water samples were collected from nine hospitals in Tehran, Iran. Temperature, pH, and residual chlorine were determined during sampling. Different virulence genes and the ability to form biofilms were subsequently analyzed among the L. pneumophila isolates. Results showed that 12 (12%) samples were positive in culture method and all of the isolates were positive as L. pneumophila species (mip). A correlation was found between Legionella culture positivity and temperature and pH of water, but there was no significant correlation between residual chlorine of water samples and the presence of Legionella. The isolation of Legionella rate in summer and spring was higher than winter and autumn. Twelve (100%) isolates were positive for mip genes, 9 (75%) for dot genes, 8 (66.66%) for hsp, 6 (50%) for lvh, and 4 (33.33%) for rtx. All of the isolates displayed strong ability for biofilm production every three days. Two of these isolates (16.6%) displayed weak ability to form biofilm on the first day of incubation. This study revealed that water sources in hospitals were colonized by virulent Legionella and should be continuously monitored to avoid elevated concentrations of Legionella with visible biofilm formation.
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Affiliation(s)
- Sara Hayatimehr
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shiva Mirkalantari
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
| | - Nour Amirmozafari
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Faramarz Masjedian Jazi
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
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Xiao X, He M, Ma L, Lv W, Huang K, Yang H, Li Y, Zou L, Xiao Y, Wang W. Insights into microbial contamination and antibiotic resistome traits in pork wholesale market: An evaluation of the disinfection effect of sodium hypochlorite. J Hazard Mater 2024; 468:133811. [PMID: 38382341 DOI: 10.1016/j.jhazmat.2024.133811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/14/2024] [Indexed: 02/23/2024]
Abstract
Chlorine and its derivatives, such as sodium hypochlorite (NaClO) and chlorine dioxide, are frequently employed as disinfectants throughout the pork supply chain in China. Nevertheless, the extensive use of NaClO has the potential to cause the creation of 'chlorine-tolerant bacteria' and accelerate the evolution of antibiotic resistance. This study evaluated the efficacy of NaClO disinfection by examining alterations in the microbiome and resistome of a pork wholesale market (PWM), and bacteria isolation and analysis were performed to validate the findings. As expected, the taxonomic compositions of bacteria was significantly different before and after disinfection. Notably, Salmonella enterica (S. enterica), Salmonella bongori (S. bongori), Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumoniae), and Pseudomonas aeruginosa (P. aeruginosa) were observed on all surfaces, indicating that the application of NaClO disinfection treatment in PWM environments for pathogenic bacteria is limited. Correlations were identified between antibiotic resistance genes (ARGs) associated with aminoglycosides (aph(3'')-I, aph(6')-I), quinolone (qnrB, abaQ), polymyxin (arnA, mcr-4) and disinfectant resistance genes (emrA/BD, mdtA/B/C/E/F). Furthermore, correlations were found between risk Rank I ARGs associated with aminoglycoside (aph(3')-I), tetracycline (tetH), beta_lactam (TEM-171), and disinfectant resistance genes (mdtB/C/E/F, emrA, acrB, qacG). Importantly, we found that Acinetobacter and Salmonella were the main hosts of disinfectant resistance genes. The resistance mechanisms of the ARGs identified in PWM were dominated by antibiotic deactivation (38.7%), antibiotic efflux (27.2%), and antibiotic target protection (14.4%). The proportion of genes encoding efflux pumps in the PWM resistome increased after disinfection. Microbial cultures demonstrated that the traits of microbial contamination and antibiotic resistane were consistent with those observed by metagenomic sequencing. This study highlights the possibility of cross-resistance between NaClO disinfectants and antibiotics, which should not be ignored.
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Affiliation(s)
- Xingning Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Miao He
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China; College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
| | - Lingyan Ma
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Wentao Lv
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Kang Huang
- Biological Systems Engineering, Washington State University, Pullman, USA
| | - Hua Yang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Yanbin Li
- Department of Biological & Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
| | - Likou Zou
- College of Resources and Environment, Sichuan Agricultural University, Chengdu, China.
| | - Yingping Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Wen Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
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Su Y, Shen X, Liu A, Zhu MJ. Evaluation of Enterococcus faecium NRRL B-2354 as a surrogate for Listeria monocytogenes during chlorine and peroxyacetic acid interventions in simulated apple dump tank water. Int J Food Microbiol 2024; 414:110613. [PMID: 38341905 DOI: 10.1016/j.ijfoodmicro.2024.110613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/23/2024] [Accepted: 01/30/2024] [Indexed: 02/13/2024]
Abstract
Sanitizers are widely incorporated in commercial apple dump tank systems to mitigate the cross-contamination of foodborne pathogens. This study validated the suitability of Enterococcus faecium NRRL B-2354 as a surrogate for Listeria monocytogenes during sanitizer interventions in dump tank water systems. E. faecium NRRL B-2354 inoculated on apples exhibited statistically equivalent susceptibility to L. monocytogenes when exposed to chlorine-based sanitizers (25-100 ppm free chlorine (FC)) and peroxyacetic acid (PAA, 20-80 ppm) in simulated dump tank water (SDTW) with 1000 ppm chemical oxygen demand (COD), resulting in 0.2-0.9 and 1.1-1.7 log CFU/apple reduction, respectively. Increasing the contact time did not affect sanitizer efficacies against E. faecium NRRL B-2354 and L. monocytogenes on apples. Chlorine and PAA interventions demonstrated statistically similar efficacies against both bacteria inoculated in SDTW. Chlorine at 25 and 100 ppm FC for 0.5-5 min contact yielded ~37.68-78.25 % and > 99.85 % inactivation, respectively, in water with 1000-4000 ppm COD, while ~51.55-99.86 % and > 99.97 % inactivation was observed for PAA at 20 and 80 ppm, respectively. No statistically significant difference was observed between the transference of E. faecium NRRL B-2354 and L. monocytogenes from inoculated apples to uninoculated apples and water, and from water to uninoculated apples during chlorine- or PAA-treated SDTW exposure. The data suggest E. faecium NRRL B-2354 is a viable surrogate for L. monocytogenes in dump tank washing systems, which could be used to predict the anti-Listeria efficacy of chlorine and PAA interventions during commercial apple processing. Further investigations are recommended to assess the suitability of E. faecium NRRL B-2354 as a surrogate for L. monocytogenes, when using different sanitizers and different types of produce to ensure reliable and comprehensive results.
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Affiliation(s)
- Yuan Su
- School of Food Science, Washington State University, Pullman, WA 99164, United States of America
| | - Xiaoye Shen
- School of Food Science, Washington State University, Pullman, WA 99164, United States of America
| | - Andrew Liu
- School of Food Science, Washington State University, Pullman, WA 99164, United States of America
| | - Mei-Jun Zhu
- School of Food Science, Washington State University, Pullman, WA 99164, United States of America.
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Zhang Z, Zhang H, Wu G, Xu X, Cao R, Wan Q, Xu H, Wang J, Huang T, Wen G. The aggregation characteristics of Aspergillus spores under various conditions and the impact on LPUV inactivation: Comparisons with chlorine-based disinfection. Water Res 2024; 253:121323. [PMID: 38377927 DOI: 10.1016/j.watres.2024.121323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 01/30/2024] [Accepted: 02/14/2024] [Indexed: 02/22/2024]
Abstract
Aggregation is the primary step prior to fungal biofilm development. Understanding the attributes of aggregation is of great significance to better control the emergence of waterborne fungi. In this study, the aggregation of Aspergills spores (A. flavus and A. fumigatus) under various salt, culture medium, and humic acid (HA) conditions was investigated for the first time, and the inactivation via low-pressure ultraviolet (LPUV) upon aggregated Aspergillus spores was also presented. The aggregation efficiency and size of aggregates increased over time and at low salt (NaCl and CaCl2) concentration (10 mM) while decreasing with the continuous increase of salt concentration (100 and 200 mM). Increasing the concentration of culture medium and HA promoted the aggregation of fungal spores. Spores became hydrated, swelled, and secreted more viscous substances during the growth period, which accelerated the aggregation process. Results also suggested that fungal spores aggregated more easily in actual water, posing a high risk of biohazard in real-life scenarios. Inactivation efficiency by LPUV decreased with higher aggregation degrees due to the protection from the damaged spores on the outer layer and the shielding of pigments in the cell wall. Compared to chlorine-based disinfection, the aggregation resulted in the extension of shoulder length yet neglectable change of inactivation rate constant under LPUV treatment. Further investigation of cell membrane integrity and intracellular reactive oxygen species was conducted to elucidate the difference in mechanisms between various techniques. This study provides insight into the understanding and controlling of the aggregation of fungal spores.
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Affiliation(s)
- Zhenghong Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Huan Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Xiangqian Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Huining Xu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China.
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Torii S, Gouttenoire J, Kumar K, Antanasijevic A, Kohn T. Influence of Amino Acid Substitutions in Capsid Proteins of Coxsackievirus B5 on Free Chlorine and Thermal Inactivation. Environ Sci Technol 2024; 58:5279-5289. [PMID: 38488515 DOI: 10.1021/acs.est.3c10409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The sensitivity of enteroviruses to disinfectants varies among genetically similar variants and coincides with amino acid changes in capsid proteins, although the effect of individual substitutions remains unknown. Here, we employed reverse genetics to investigate how amino acid substitutions in coxsackievirus B5 (CVB5) capsid proteins affect the virus' sensitivity to free chlorine and heat treatment. Of ten amino acid changes observed in CVB5 variants with free chlorine resistance, none significantly reduced the chlorine sensitivity, indicating a minor role of the capsid composition in chlorine sensitivity of CVB5. Conversely, a subset of these amino acid changes located at the C-terminal region of viral protein 1 led to reduced heat sensitivity. Cryo-electron microscopy revealed that these changes affect the assembly of intermediate viral states (altered and empty particles), suggesting that the mechanism for reduced heat sensitivity could be related to improved molecular packing of CVB5, resulting in greater stability or altered dynamics of virus uncoating during infection.
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Affiliation(s)
- Shotaro Torii
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jérôme Gouttenoire
- Division of Gastroenterology and Hepatology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland
| | - Kiruthika Kumar
- Virology and Structural Immunology Laboratory, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Aleksandar Antanasijevic
- Virology and Structural Immunology Laboratory, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Tamar Kohn
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Sousa M, Oliveira IM, Correia L, Gomes IB, Sousa CA, Braga DFO, Simões M. Far-UV-C irradiation promotes synergistic bactericidal action against adhered cells of Escherichia coli and Staphylococcus epidermidis. Sci Total Environ 2024; 917:170352. [PMID: 38286293 DOI: 10.1016/j.scitotenv.2024.170352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/17/2024] [Accepted: 01/20/2024] [Indexed: 01/31/2024]
Abstract
The contamination of indoor areas is a global health problem that can cause the dispersion of infectious diseases. In that sense, it is urgent to find new strategies applying a lower concentration of the traditional chemicals used for cleaning and disinfection. Ultraviolet radiation (UV), in particular far-UV-C (200-225 nm), has emerged as a successful, powerful, easy-to-apply, and inexpensive approach for bacterial eradication that still requires scientific assessment. This study investigated new strategies for disinfection based on far-UV-C (222 nm) combined with chlorine and mechanical cleaning, providing an innovative solution using low doses. The bactericidal activity of far-UV-C (222 nm) was tested at an intensity of irradiation from 78.4 μW/cm2 to 597.7 μW/cm2 (for 1 min) against Escherichia coli and Staphylococcus epidermidis adhered on polystyrene microtiter plates. It was further tested in combination with mechanical cleaning (ultrasounds for 1 min) and free chlorine (0.1, 0.5, and 1 mg/L for 5 min). The triple combination consisting of mechanical cleaning + free chlorine (0.5 mg/L) + far-UV-C (54 mJ/cm2) was tested against cells adhered to materials found in hospital settings and other public spaces: polyvinyl chloride (PVC), stainless steel (SS), and polyetheretherketone (PEEK). Disinfection with far-UV-C (54 mJ/cm2) and free chlorine at 0.5 mg/L for 5 min allowed a total reduction of culturable E. coli cells and a logarithmic reduction of 2.98 ± 0.03 for S. epidermidis. The triple combination of far-UV-C, free chlorine, and mechanical cleaning resulted in a total reduction of culturable cells for both adhered bacteria. Bacterial adhesion to PVC, SS, and PEEK occurred at distinct extents and influenced the bactericidal activity of the triple combination, with logarithmic reductions of up to three. The overall results highlight that, based on culturability assessment, far-UV-C (54 mJ/cm2) with chlorine (0.5 mg/L; 5 min) and mechanical cleaning (1 min) as an efficient disinfection strategy using mild conditions. The combination of culturability and viability assessment of disinfection is recommended to detect regrowth events and increase the effectiveness in microbial growth control.
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Affiliation(s)
- M Sousa
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, Department of Chemical Engineering, University of Porto, 4200-465 Porto, Portugal; ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal
| | - I M Oliveira
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, Department of Chemical Engineering, University of Porto, 4200-465 Porto, Portugal; ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal
| | - L Correia
- SpinnerDynamics, Lda., Rua da Junta de Freguesia 194, 4540-322 Escariz, Arouca, Portugal
| | - I B Gomes
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, Department of Chemical Engineering, University of Porto, 4200-465 Porto, Portugal; ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal
| | - C A Sousa
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, Department of Chemical Engineering, University of Porto, 4200-465 Porto, Portugal; ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal
| | - D F O Braga
- SpinnerDynamics, Lda., Rua da Junta de Freguesia 194, 4540-322 Escariz, Arouca, Portugal
| | - M Simões
- LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, Department of Chemical Engineering, University of Porto, 4200-465 Porto, Portugal; ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal.
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11
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Wang M, Sun H, Ma X, Wang H, Shi B. Metabolic response of bacterial community to sodium hypochlorite and ammonia nitrogen affected the antibiotic resistance genes in pipelines biofilm. Water Res 2024; 252:121179. [PMID: 38324986 DOI: 10.1016/j.watres.2024.121179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/06/2024] [Accepted: 01/22/2024] [Indexed: 02/09/2024]
Abstract
The biofilm is important for the antibiotic resistance genes (ARGs) propagation in drinking water pipelines. This study investigated the influence of chlorine disinfection and ammonia nitrogen on the ARGs in pipelines biofilm using metagenomic and metabolomics analysis. Chlorine disinfection reduced the relative abundance of unclassified_c_Actinobacteria, Acidimicrobium, and Candidatus_Pelagibacter to 394-430 TPM, 114-123 TPM, and 49-54 TPM, respectively. Correspondingly, the ARGs Saur_rpoC_DAP, macB, and mfd was reduced to 8-12 TPM, 81-92 TPM and 30-35 TPM, respectively. The results of metabolomics suggested that chlorine disinfection suppressed the pathways of ABC transporters, fatty acid biosynthesis, biosynthesis of unsaturated fatty acids, and biosynthesis of amino acids. These pathways were related to the cell membrane integrality and extracellular polymeric substances (EPS) secretion. Chlorine disinfection induced the decrease of EPS-related genes, resulting in the lower relative abundance of bacterial community and their antibiotic resistance. However, added approximately 0.5 mg/L NH3-N induced up-regulation of these metabolic pathways. In addition, NH3-N addition increased the relative abundance of enzymes related to inorganic and organic nitrogen metabolic pathway significantly, such as ammonia monooxygenase, glutamine synthetase, and glutamate synthase. Due to the EPS protection and nitrogen metabolism, the relative abundance of the main bacterial genera and the related ARGs increased to the level equal to that in pipelines biofilm with no disinfection. Therefore, NH3-N reduced the ARGs removal efficiency of chlorine disinfection. It is necessary to take measures to improve the removal rate of NH3-N and ARGs for preventing their risks in drinking water.
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Affiliation(s)
- Min Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Huifang Sun
- Institute of Resources and Environmental Engineering, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Xu Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Allende A, Férez-Rubio JA, Tudela JA, Aznar R, Gil MI, Sánchez G, Randazzo W. Human intestinal enteroids and predictive models validate the operational limits of sanitizers used for viral disinfection of vegetable process wash water. Int J Food Microbiol 2024; 413:110601. [PMID: 38301540 DOI: 10.1016/j.ijfoodmicro.2024.110601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 11/20/2023] [Accepted: 01/20/2024] [Indexed: 02/03/2024]
Abstract
Vegetables are globally associated with a considerable number of foodborne outbreaks caused by viral infections, specifically human norovirus. In fresh produce industry, washing represents a critical step for food safety as process wash water (PWW) needs to be maintained at appropriate microbial quality to prevent water-mediated cross-contamination. This study aimed to explore the disinfection efficacy of chlorine (free chlorine, FC), chlorine dioxide (ClO2) and peracetic acid (PAA) in PWW against infectious human norovirus and Tulane virus (TV). First, we tested the extent of TV inactivation in baby leaf, bell pepper, and vegetables mix PWW and monitored the viral decay by cell culture. Then, inactivation kinetics were defined for infectious human norovirus exposed to FC, ClO2 and PAA in baby leaves PWW using the human intestinal enteroids (HIE) system. Finally, kinetic inactivation models were fitted to TV reduction and decay of sanitizers to aid the implementation of disinfection strategies. Results showed that >8 log10 human norovirus and 3.9 log10 TV were inactivated by 20 ppm FC within 1 min; and by 3 ppm ClO2 in 1 min (TV) or 5 min (norovirus). PAA treatment at 80 ppm reduced ca. 2 log10 TV but not completely inactivated the virus even after 20 min exposure, while 5 min treatment prevented norovirus replication in HIE. TV inactivation in PWWs was described using an exponential decay model. Taking these data together, we demonstrated the value of applying the HIE model to validate current operational limits for the most commonly used sanitizers. The inactivation kinetics for human norovirus and TV, along with the predictive model described in this study expand the current knowledge to implement post-harvest produce safety procedures in industry settings.
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Affiliation(s)
- Ana Allende
- Research Group on Microbiology and Quality of Fruits and Vegetables (MxQ), Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
| | - José Antonio Férez-Rubio
- Research Group on Microbiology and Quality of Fruits and Vegetables (MxQ), Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
| | - Juan Antonio Tudela
- Research Group on Microbiology and Quality of Fruits and Vegetables (MxQ), Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
| | - Rosa Aznar
- Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, Av. Agustín Escardino 7, Paterna 46980, Valencia, Spain; Department of Microbiology and Ecology, University of Valencia, Valencia, Spain
| | - Maria Isabel Gil
- Research Group on Microbiology and Quality of Fruits and Vegetables (MxQ), Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
| | - Gloria Sánchez
- Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, Av. Agustín Escardino 7, Paterna 46980, Valencia, Spain
| | - Walter Randazzo
- Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, Av. Agustín Escardino 7, Paterna 46980, Valencia, Spain.
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13
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Chen X, Wu XN, Feng JC, Wang Y, Zhang XC, Lin YL, Wang B, Zhang S. Nonlinear differential equations and their application to evaluating the integrated impacts of multiple parameters on the biochemical safety of drinking water. J Environ Manage 2024; 355:120493. [PMID: 38452624 DOI: 10.1016/j.jenvman.2024.120493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/11/2024] [Accepted: 02/22/2024] [Indexed: 03/09/2024]
Abstract
The present study aimed to narrow such gaps by applying nonlinear differential equations to biostability in drinking water. Biostability results from the integrated dynamics of nutrients and disinfectants. The linear dynamics of biostability have been well studied, while there remain knowledge gaps concerning nonlinear effects. The nonlinear effects are explained by phase plots for specific scenarios in a drinking water system, including continuous nutrient release, flush exchange with the adjacent environment, periodic pulse disinfection, and periodic biofilm development. The main conclusions are, (1) The correlations between the microbial community and nutrients go through phases of linear, nonlinear, and chaotic dynamics. Disinfection breaks the chaotic phase and returns the system to the linear phase, increasing the microbial growth potential. (2) Post-disinfection after multiple microbial peaks produced via metabolism can increase disinfection efficiency and decrease the risks associated with disinfectant byproduct risks. This can provide guidelines for optimizing the disinfection strategy, according to the long-term water safety target or a short management. Limited disinfection and ultimate disinfection may be more effective and have low chemical risk, facing longer stagnant conditions. (3) Periodic biofilm formation and biofilm detachment increase the possibility of uncertainty in the chaotic phase. For future study, nonlinear differential equation models can accordingly be applied at the molecular and ecological levels to further explore more nonlinear regulation mechanisms.
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Affiliation(s)
- Xiao Chen
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China; School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Xiao-Nan Wu
- School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Jing-Chun Feng
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China; School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Yi Wang
- College of Defense Engineering, The Army Engineering University of PLA, Nanjing, 210007, China.
| | - Xiao-Chun Zhang
- School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Yi-Lei Lin
- School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Bin Wang
- School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Si Zhang
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China; School of Ecology, Environment, and Resources, Guangdong University of Technology, Guangzhou, 510006, China.
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14
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Zhang J, Li W, Zhang X, Wang X, Lv L. Combined applications of UV and chlorine on antibiotic resistance control: A critical review. Environ Res 2024; 243:117884. [PMID: 38072103 DOI: 10.1016/j.envres.2023.117884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/03/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023]
Abstract
Environmental health problems caused by antibiotic-resistant bacteria (ARB) and antibiotic-resistant genes (ARGs) have become a global concern. ARB and ARGs have been continuously detected in various water environments, which pose a new challenge for water quality safety assurance. Disinfection is a key water treatment process to eliminate pathogenic microorganisms in water, and combined chlorine and UV processes (the UV/Cl2 process, the UV-Cl2 process, and the Cl2-UV process) are considered potential disinfection methods to control antibiotic resistance. This review documented the efficacy and mechanism of combined UV and chlorine processes for the control of antibiotic resistance, as well as the effects of chlorine dose, solution pH, UV wavelength, and water matrix on the effectiveness of the processes. There are knowledge gaps in research on the combined chlorine and UV processes for antibiotic resistance control, in particular the UV-Cl2 process and the Cl2-UV process. In addition, changes in the structure of microbial communities and the distribution of ARGs, which are closely related to the spread of antibiotic resistance in the water, induced by combined processes were also addressed. Whether these changes could lead to the re-transmission of antibiotic resistance and harm human health may need to be further evaluated.
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Affiliation(s)
- Jingyi Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Xinran Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xuhui Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Longyi Lv
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China
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15
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Cao R, Tan L, Wan Q, Wu G, Wang J, Lin Y, Huang T, Wen G. The improved resistance of germinated spores to ultraviolet irradiation: Comparison with chlorine. Chemosphere 2024; 349:140929. [PMID: 38092169 DOI: 10.1016/j.chemosphere.2023.140929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 12/07/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
Fungi outbreaks in water will include a series of processes, including spore aggregation, germination, biofilm, and finally present in a mixed state in the aquatic environment. More attention is paid to the control of dispersed fungal spores, however, there was little knowledge of the control of germinated spores. This study investigated the inactivation kinetics and mechanism of ultraviolet (UV) treatment for fungal spores with different germination percentages compared with dormant spores. The results indicated that the inactivation rate constants (k) of spores with 5%-45% germination were 0.0278-0.0299 cm2/mJ for Aspergillus niger and 0.0588-0.0647 cm2/mJ for Penicillium polonicum, which were lower than those of dormant spores. It suggested that germinated spores were more tolerant to UV irradiation than dormant spores, and it may be due to the defensive barrier (upregulated pigments) and some reductive substance (upregulated enoyl reductase) by absorbing UV or reacting with reactive oxygen species according to transcriptome analysis. Compared to dormant spores, the k-UV of germinated spores decreased by 18.17%-26.56% for Aspergillus niger, which was less than k-chlorine (62.33%-69.74%). A slighter decrease in k-UV showed UV irradiation can efficiently control fungi contamination, especially when dormant spores and germinated spores coexisted in actual water systems. This study indicates that more attention should be paid to germinated spores.
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Affiliation(s)
- Ruihua Cao
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Lili Tan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Qiqi Wan
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Gehui Wu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Jingyi Wang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Yingzi Lin
- School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, PR China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China
| | - Gang Wen
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China.
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16
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Tang MLY, Lau SCK. Effects of chlorination on the survival of sewage bacteria in seawater microcosms. Environ Microbiol Rep 2024; 16:e13216. [PMID: 37990630 PMCID: PMC10866060 DOI: 10.1111/1758-2229.13216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/03/2023] [Indexed: 11/23/2023]
Abstract
Chlorination is a commonly used disinfection method in sewage treatment process. However, resistant bacteria may survive chlorination and enter the receiving aquatic environment upon effluent discharge. There has been limited research on the effects of chlorination on bacterial survival in seawater. To address this knowledge gap, microcosm experiments were conducted to simulate the discharge of chlorinated effluents into coastal seawater. The results revealed that bacterial communities in seawater-based effluents survived better in seawater than those in freshwater-based effluents. High chlorine dosages could significantly reduce the viable bacterial populations and their chance of regrowth in seawater. Additionally, faecal indicator bacteria (FIB) that entered the viable but non-culturable (VBNC) state under chlorination tended to persist in the VBNC state without resuscitation during seawater incubation. Because of the prevalence of VBNC indicator bacteria, qPCR quantification of FIB was more effective than conventional culture-based methods in tracing viable pathogenic chlorine-resistant bacteria, although the correlation strength varied depending on the type of effluent. This study sheds light on how chlorine dosages and the intrinsic properties of effluents affect bacterial survival in seawater and highlights the potential and limitations of using FIB in monitoring the health risks associated with the discharge of chlorinated effluents.
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Affiliation(s)
- Mandy Lok Yi Tang
- Department of Ocean ScienceHong Kong University of Science and TechnologyHong KongChina
| | - Stanley Chun Kwan Lau
- Department of Ocean ScienceHong Kong University of Science and TechnologyHong KongChina
- Center for Ocean Research in Hong Kong and MacauHong Kong University of Science and TechnologyHong KongChina
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17
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Ke Y, Sun W, Chen Z, Zhu Y, Chen X, Yan S, Li Y, Xie S. Effects of disinfectant type and dosage on biofilm's activity, viability, microbiome and antibiotic resistome in bench-scale drinking water distribution systems. Water Res 2024; 249:120958. [PMID: 38064782 DOI: 10.1016/j.watres.2023.120958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 11/29/2023] [Accepted: 11/30/2023] [Indexed: 01/03/2024]
Abstract
Drinking water distribution systems (DWDSs) are important for supplying high-quality water to consumers and disinfectant is widely used to control microbial regrowth in DWDSs. However, the disinfectant's influences on microbial community and antibiotic resistome in DWDS biofilms and the underlying mechanisms driving their dynamics remain elusive. The study investigated the effects of chlorine and chloramine disinfection on the microbiome and antibiotic resistome of biofilms in bench-scale DWDSs using metagenomics assembly. Additionally, the biofilm activity and viability were monitored based on adenosine triphosphate (ATP) and flow cytometer (FCM) staining. The results showed that both chlorine and chloramine disinfectants decreased biofilm ATP, although chloramine at a lower dosage (1 mg/L) could increase it. Chloramine caused a greater decrease in living cells than chlorine. Furthermore, the disinfectants significantly lowered the microbial community diversity and altered microbial community structure. Certain bacterial taxa were enriched, such as Mycobacterium, Sphingomonas, Sphingopyxis, Azospira, and Dechloromonas. Pseudomonas aeruginosa exhibited high resistance towards disinfectants. The disinfectants also decreased the complexity of microbial community networks. Some functional taxa (e.g., Nitrospira, Nitrobacter, Nitrosomonas) were identified as keystones in chloramine-treated DWDS microbial ecological networks. Stochasticity drove biofilm microbial community assembly, and disinfectants increased the contributions of stochastic processes. Chlorine had greater promotion effects on antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and ARG hosts than chloramine. The disinfectants also selected pathogens, such as Acinetobacter baumannii and Klebsiella pneumonia, and these pathogens also harbored ARGs and MGEs. Overall, this study provides new insights into the effects of disinfectants on biofilm microbiome and antibiotic resistome, highlighting the importance of monitoring and managing disinfection practices in DWDSs.
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Affiliation(s)
- Yanchu Ke
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, China.
| | - Zhongyun Chen
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Ying Zhu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiuli Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shuang Yan
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yangyang Li
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shuguang Xie
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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18
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Marzec J, Nadadur S. Countermeasures against Pulmonary Threat Agents. J Pharmacol Exp Ther 2024; 388:560-567. [PMID: 37863486 PMCID: PMC10801713 DOI: 10.1124/jpet.123.001822] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 10/02/2023] [Accepted: 10/04/2023] [Indexed: 10/22/2023] Open
Abstract
Inhaled toxicants are used for diverse purposes, ranging from industrial applications such as agriculture, sanitation, and fumigation to crowd control and chemical warfare, and acute exposure can induce lasting respiratory complications. The intentional release of chemical warfare agents (CWAs) during World War I caused life-long damage for survivors, and CWA use is outlawed by international treaties. However, in the past two decades, chemical warfare use has surged in the Middle East and Eastern Europe, with a shift toward lung toxicants. The potential use of industrial and agricultural chemicals in rogue activities is a major concern as they are often stored and transported near populated areas, where intentional or accidental release can cause severe injuries and fatalities. Despite laws and regulatory agencies that regulate use, storage, transport, emissions, and disposal, inhalational exposures continue to cause lasting lung injury. Industrial irritants (e.g., ammonia) aggravate the upper respiratory tract, causing pneumonitis, bronchoconstriction, and dyspnea. Irritant gases (e.g., acrolein, chloropicrin) affect epithelial barrier integrity and cause tissue damage through reactive intermediates or by direct adduction of cysteine-rich proteins. Symptoms of CWAs (e.g., chlorine gas, phosgene, sulfur mustard) progress from airway obstruction and pulmonary edema to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), which results in respiratory depression days later. Emergency treatment is limited to supportive care using bronchodilators to control airway constriction and rescue with mechanical ventilation to improve gas exchange. Complications from acute exposure can promote obstructive lung disease and/or pulmonary fibrosis, which require long-term clinical care. SIGNIFICANCE STATEMENT: Inhaled chemical threats are of growing concern in both civilian and military settings, and there is an increased need to reduce acute lung injury and delayed clinical complications from exposures. This minireview highlights our current understanding of acute toxicity and pathophysiology of a select number of chemicals of concern. It discusses potential early-stage therapeutic development as well as challenges in developing countermeasures applicable for administration in mass casualty situations.
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Affiliation(s)
- Jacqui Marzec
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina
| | - Srikanth Nadadur
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina
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19
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Zhang T, Liao P, Fang L, Zhang D. Effect of booster disinfection on the prevalence of microbial antibiotic resistance and bacterial community in a simulated drinking water distribution system. Environ Pollut 2024; 341:122902. [PMID: 37949160 DOI: 10.1016/j.envpol.2023.122902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/30/2023] [Accepted: 11/07/2023] [Indexed: 11/12/2023]
Abstract
Booster disinfection was often applied to control the microorganism's growth in long-distance water supply systems. The effect of booster disinfection on the changing patterns of antibiotic resistance and bacterial community was investigated by a simulated water distribution system (SWDS). The results showed that the antibiotic resistance bacteria (ARB) and antibiotic resistance genes (ARGs) were initially removed after dosing disinfectants (chlorine and chloramine), but then increased with the increasing water age. However, the relative abundance of ARGs significantly increased after booster disinfection both in buck water and biofilm, then decreased along the pipeline. The pipe materials and disinfectant type also affected the antibiotic resistance. Chlorine was more efficient in controlling microbes and ARGs than chloramine. Compared with UPVC and PE pipes, SS pipes had the lowest total bacteria, ARB concentration, and ARB percentage, mainly due to higher disinfectant residuals and a smoother surface. The significant correlation (rs = 0.77, p < 0.001) of the 16S rRNA genes was observed between buck water and biofilm, while the correlations of targeted ARGs were found to be weak. Bray-Curtis similarity index indicated that booster disinfection significantly changed the biofilm bacterial community and the disinfectant type also had a marked impact on the bacterial community. At the genus level, the relative abundance of Pseudomonas, Sphingomonas, and Methylobacterium significantly increased after booster disinfection. Mycobacterium increased after chloramination while decreased after chlorination, indicating Mycobacterium might resist chloramine. Pseudomonas, Methylobacterium, and Phreatobacter were found to correlate well with the relative abundance of ARGs. These results highlighted antibiotic resistance shift and bacterial community alteration after booster disinfection, which may be helpful in controlling potential microbial risk in drinking water.
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Affiliation(s)
- Tuqiao Zhang
- College of Civil Engineering and Architecture Zhejiang University, Hangzhou, 310058, China; Future Water Laboratory, Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing, 314000, China; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, 310058, China.
| | - Pubin Liao
- College of Civil Engineering and Architecture Zhejiang University, Hangzhou, 310058, China; Future Water Laboratory, Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing, 314000, China; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, 310058, China.
| | - Lei Fang
- College of Civil Engineering and Architecture Zhejiang University, Hangzhou, 310058, China; Future Water Laboratory, Innovation Center of Yangtze River Delta, Zhejiang University, Jiaxing, 314000, China; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, 310058, China.
| | - Dongyang Zhang
- College of Civil Engineering and Architecture Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Hangzhou, 310058, China.
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20
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Ren X, Zhang S, Wu M, Xiao B, Miao H, Chen H. Effect and influence mechanism of biofilm formation on the biological stability of reclaimed water. Sci Total Environ 2024; 906:167735. [PMID: 37827320 DOI: 10.1016/j.scitotenv.2023.167735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 10/08/2023] [Accepted: 10/08/2023] [Indexed: 10/14/2023]
Abstract
Microorganisms and sediments in reclaimed water adhere to the inner walls of pipes or water tanks, forming biofilms that support the continuous growth of microorganisms. These biofilms provide a protective barrier, shielding bacteria from disinfectants. This study investigated the impact of biofilms on bacterial growth and reproduction in reclaimed water and the factors limiting bacterial growth in reclaimed graywater (GMR) and reclaimed mixed wastewater (MWR). The results revealed that biofilm biomass gradually increased and reached a maximum value on Days 20-25, and the biomass of organisms continued to decrease after 40 days. Biofilms serve as a source of bacteria, continuously releasing them into reclaimed water systems. The presence of biofilms reduced the biological stability of the reclaimed water, leading to water quality deterioration. The concentration of assimilable organic carbon in the reclaimed water showed a positive correlation with the heterotrophic bacterial count and Escherichia coli levels in both the reclaimed water and biofilms. The threshold value of chlorine for inhibiting biofilms in reclaimed water was no <2 mg/L. High concentrations of free chlorine delayed the growth of biofilms but did not reduce the final biomass generated by the biofilms. Carbon was the limiting factor for the biological stability of reclaimed water, while nitrogen, phosphorus, and inorganic salts were not limiting factors. Thus, minimizing the concentration of organic matter in reclaimed water can reduce the nutrient sources available for biofilm formation. This study provides support for advancements in the wastewater reuse industry.
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Affiliation(s)
- Xueli Ren
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China.
| | - Shudong Zhang
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Mengyi Wu
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Beiqi Xiao
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Hengfeng Miao
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Hongbin Chen
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
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21
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Li J, Wang Y, Zheng W, Xia T, Kong X, Yuan Z, Niu B, Wei G, Li B. Comprehensive evaluation of treating drinking water for laying hens using slightly acidic electrolyzed water. Poult Sci 2024; 103:103176. [PMID: 37939586 PMCID: PMC10665938 DOI: 10.1016/j.psj.2023.103176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/27/2023] [Accepted: 10/06/2023] [Indexed: 11/10/2023] Open
Abstract
Slightly acidic electrolyzed water (SAEW) is well-known for its highly potent antibacterial properties and safe residue-free nature. In this study, a comprehensive evaluation was conducted on 2 disinfection methods for waterline cleaning in poultry houses: (1) continuously add SAEW into the waterline and (2) the conventional waterline disinfection method, which includes regular use of high-concentration chemical disinfectant for soaking the waterline and flushing with water. The evaluation focused on the effects of these methods on bacteria levels in laying hens' drinking water, the fecal normal rate of laying hens, egg quality, as well as the economic costs and water footprint associated with each method. The results show that the inhibition rate of the control group was 52.45% to 80.36%, which used 1500 mg/L sodium dichloroisocyanurate (DCCNa) for soaking and then flushing with water. The bacterial levels in the waterline returned to pre-treatment levels 26 h after cleaning. However, the experimental group with an available chlorine concentration (ACC) of 0.3 mg/L SAEW showed a higher inhibition rate (99.90%) than the control group (P < 0.05) and exhibited a sustained antimicrobial effect. Regarding eggshell thickness, eggshell strength, and Haugh units of the egg, there were no significant differences between the experimental and control groups. However, the experimental group had higher egg weight and darker yolk color (P < 0.05) than those of the control group. Besides, the experimental group exhibited a higher fecal normal rate and a lower water footprint than those of the control group. Hence, SAEW represents a favorable choice for disinfecting drinking water in poultry houses due to its ease of preparation, lack of residue, energy efficiency, and efficient antibacterial properties. To ensure adequate sanitation, it is recommended to incorporate SAEW with an ACC of 0.3 mg/L into the daily management of the drinking water system for laying hens.
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Affiliation(s)
- Jian Li
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, 100083, Beijing, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs, 100083, Beijing, China; Beijing Engineering Research Center on Animal Healthy Environment, 100083, Beijing, China
| | - Yang Wang
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, 100083, Beijing, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs, 100083, Beijing, China; Beijing Engineering Research Center on Animal Healthy Environment, 100083, Beijing, China
| | - Weichao Zheng
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, 100083, Beijing, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs, 100083, Beijing, China; Beijing Engineering Research Center on Animal Healthy Environment, 100083, Beijing, China
| | - Tong Xia
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, 100083, Beijing, China
| | - Xiangbing Kong
- Ruiande Environmental Protection Equipment Co., LTD., Beijing 102600, China
| | - Zhengdong Yuan
- Beijing Deqingyuan Agricultural Technology Co., Ltd., Beijing 102115, China
| | - Binglong Niu
- Beijing Deqingyuan Agricultural Technology Co., Ltd., Beijing 102115, China
| | - Guowen Wei
- Beijing Deqingyuan Agricultural Technology Co., Ltd., Beijing 102115, China
| | - Baoming Li
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources and Civil Engineering, China Agricultural University, 100083, Beijing, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs, 100083, Beijing, China; Beijing Engineering Research Center on Animal Healthy Environment, 100083, Beijing, China.
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22
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Wang Y, Ma B, Zhao J, Tang Z, Li W, He C, Xia D, Linden KG, Yin R. Rapid Inactivation of Fungal Spores in Drinking Water by Far-UVC Photolysis of Free Chlorine. Environ Sci Technol 2023; 57:21876-21887. [PMID: 37978925 DOI: 10.1021/acs.est.3c05703] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Effective and affordable disinfection technology is one key to achieving Sustainable Development Goal 6. In this work, we develop a process by integrating Far-UVC irradiation at 222 nm with free chlorine (UV222/chlorine) for rapid inactivation of the chlorine-resistant and opportunistic Aspergillus niger spores in drinking water. The UV222/chlorine process achieves a 5.0-log inactivation of the A. niger spores at a chlorine dosage of 3.0 mg L-1 and a UV fluence of 30 mJ cm-2 in deionized water, tap water, and surface water. The inactivation rate constant of the spores by the UV222/chlorine process is 0.55 min-1, which is 4.6-fold, 5.5-fold, and 1.8-fold, respectively, higher than those of the UV222 alone, chlorination alone, and the conventional UV254/chlorine process under comparable conditions. The more efficient inactivation by the UV222/chlorine process is mainly attributed to the enhanced generation of reactive chlorine species (e.g., 6.7 × 10-15 M of Cl•) instead of hydroxyl radicals from UV222 photolysis of chlorine, which is verified through both experiments and a kinetic model. We further demonstrate that UV222 photolysis damages the membrane integrity and benefits the penetration of chlorine and radicals into cells for inactivation. The merits of the UV222/chlorine process over the UV254/chlorine process also include the more effective inhibition of the photoreactivation of the spores after disinfection and the lower formation of chlorinated disinfection byproducts and toxicity.
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Affiliation(s)
- Yongyi Wang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong
| | - Ben Ma
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Jing Zhao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong
| | - Zhuoyun Tang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Wanxin Li
- Department of Health and Environmental Sciences, Xi'an Jiaotong-Liverpool University, Suzhou 215000, China
| | - Chun He
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Dehua Xia
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Karl G Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong
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23
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Helou M, Mahdi A, Abou Fayad A, Sleiman A, Matar GM, Zoghbi S, Madani T, Husni R. Antimicrobial effects of chlorine dioxide in a hospital setting. Sci Rep 2023; 13:22866. [PMID: 38129523 PMCID: PMC10739700 DOI: 10.1038/s41598-023-49997-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023] Open
Abstract
Chlorine dioxide is a powerful disinfectant with strong antibacterial properties. We conducted a study at different sites of the Lebanese American University Medical Center-Rizk Hospital to determine the efficacy of the ECOM air mask in decreasing the particle load. Air cultures were obtained from three different locations, namely the patients' elevator, visitors' elevator and mobile clinic and the number of colonies grown on each type of agar was determined. We also measured particle counts at the three sites both at baseline and after placement of the ECOM air mask. After 7 days of ECOM air mask use, the numbers of colonies grown on all types of media was decreased by 20-100% versus the baseline values. The counts of particles of different diameters (0.3, 0.5 and 5 µm) were decreased at all three sampled sites. This study highlighted the efficacy of the ECOM air mask. The utility of the gaseous form of ClO2 as an antiseptic in the hospital setting appears promising.
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Affiliation(s)
- Mariana Helou
- Division of Emergency, Department of Internal Medicine, School of Medicine, Lebanese American University, Beirut, Lebanon
| | - Ahmad Mahdi
- Division of Infectious Diseases, Department of Internal Medicine, School of Medicine, Lebanese American University, Beirut, Lebanon
| | - Antoine Abou Fayad
- Center for Infectious Diseases Research, American University of Beirut, Beirut, Lebanon
| | - Ahmad Sleiman
- Center for Infectious Diseases Research, American University of Beirut, Beirut, Lebanon
| | - Ghassan M Matar
- Center for Infectious Diseases Research, American University of Beirut, Beirut, Lebanon
| | - Sanaa Zoghbi
- Infection Control Program, Lebanese American University Medical Center, Beirut, Lebanon
| | - Tarek Madani
- Infection Control Program, Lebanese American University Medical Center, Beirut, Lebanon
| | - Rola Husni
- Division of Infectious Diseases, Department of Internal Medicine, School of Medicine, Lebanese American University, Beirut, Lebanon.
- Lebanese American University-Rizk Hospital, Beirut, Lebanon.
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24
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Sun YG, Wang HB, Wu YH, Cao KF, Chen Z, Ikuno N, Koji N, Hu HY. High-efficiency and low-carbon inactivation of UV resistant bacteria in reclaimed water by flow-through electrode system (FES). Sci Total Environ 2023; 904:166297. [PMID: 37595918 DOI: 10.1016/j.scitotenv.2023.166297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/20/2023]
Abstract
With the increasingly serious shortage of water resources globally, it has been paid more attention on how to secure the biosafety of reclaimed water and other non-traditional water sources. However, the 3 most applied disinfection technics, which are chlorine, ultraviolet (UV), and ozone disinfection, all have their disadvantages of selecting undesired bacteria and low energy utilization efficiency. Electrode disinfection is a promising solution, but the current electrode disinfection process still needs to be optimized in terms of the use conditions of the configuration reactivation. In this paper, we built a flow electrode system (FES). To evaluate the disinfection techniques more precisely, we isolated ultraviolet-resistant bacteria (URB) bacteria from the water of the full-scale water plant and tested the disinfection performance of FES and UV. The inactivation rate, reactivation potential, and energy consumption were analyzed. FES could inactivate 99.99 % of the URB and cause irreversible damage to the residual bacteria. FES could make all bacteria strains apoptosis in the subsequent 24 h of storage after alternating pulse current (APC) treatment, 3 V, within 27.7 s. Besides, the energy consumption of FES is about 2 orders lower than that of UV disinfection under the same inactivation rate. In summary, APC-FES is an efficient and low-carbon alternative for future water disinfection, which could achieve the ideal disinfection effect of a high inactivation rate, no reactivation, and low energy consumption.
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Affiliation(s)
- Yi-Ge Sun
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Nakata Koji
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, PR China
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25
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Zheng S, Lin T, Zhang X, Jiang F. Response mechanisms of pipe wall biofilms in water supply networks under different disinfection strategy pressures and the effect of mediating halogenated acetonitrile formation. Chemosphere 2023; 344:140382. [PMID: 37806328 DOI: 10.1016/j.chemosphere.2023.140382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 08/23/2023] [Accepted: 10/05/2023] [Indexed: 10/10/2023]
Abstract
Residual chlorine and biofilm coexistence is inevitable in drinking water transmission and distribution networks. Understanding the microbial response and its mediated effects on disinfection byproducts under different categories of residual chlorine stress is essential to ensure water safety. The aim of our study was to determine the response of pipe wall biofilms to residual chlorine pressure in chlorine and chloramine systems and to understand the microbially mediated effects on the formation and migration of haloacetonitriles (HANs), typical nitrogenous disinfection byproducts. According to the experimental results, the biofilm response changes under pressure, with significant differences noted in morphological characteristics, the extracellular polymeric substances (EPS) spatial structure, bacterial diversity, and functional abundance potential. Upon incubation with residual chlorine (1.0 ± 0.2 mg/L), the biofilm biomass per unit area, EPS, community abundance, and diversity increased in the chloramine group, and the percentage of viable bacteria increased, potentially indicating that the chloramine group provides a richer variety of organic matter precursors. Compared with the chloramine group, the chlorination group exhibited increased haloacetonitrile formation potential (HANFP), with Rhodococcus (43.2%) dominating the system, whereas the prediction abundance of metabolic functions was advantageous, especially with regard to amino acid metabolism, carbohydrate metabolism, and the biodegradation and metabolism of foreign chemicals. Under chlorine stress, pipe wall biofilms play a stronger role in mediating HAN production. It is inferred that chlorine may stimulates microbial interactions, and more metabolites (e.g., EPS) consume chlorine to protect microbial survival. EPS dominates in biofilms, in which proteins exhibit greater HANFP than polysaccharides.
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Affiliation(s)
- Songyuan Zheng
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Xue Zhang
- Suzhou Water Supply Company, Suzhou, 215002, China
| | - Fuchun Jiang
- Suzhou Water Supply Company, Suzhou, 215002, China
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26
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Mehdipour M, Gholipour S, Mohammadi F, Hatamzadeh M, Nikaeen M. Incidence of co-resistance to antibiotics and chlorine in bacterial biofilm of hospital water systems: Insights into the risk of nosocomial infections. J Infect Public Health 2023; 16 Suppl 1:210-216. [PMID: 37951730 DOI: 10.1016/j.jiph.2023.10.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023] Open
Abstract
The presence of biofilms in drinking water distribution systems (DWDS) in healthcare settings poses a considerable risk to the biological security of water, particularly when the biofilm bacteria demonstrate antimicrobial resistance characteristics. This study aimed to investigate the occurrence of antibiotic-resistant bacteria (ARB) in biofilms within DWDS of hospitals. The chlorine resistance of the isolated ARB was analyzed, and then chlorine-resistant bacteria (CRB) were identified using molecular methods. Additionally, the presence of several antibiotic resistance genes (ARGs) was monitored in the isolated ARB. Out of the 41 biofilm samples collected from hospitals, ARB were detected in 32 (78%) of the samples. A total of 109 colonies of ARB were isolated from DWDS of hospitals, with β-lactam resistant bacteria, including ceftazidime-resistant and ampicillin-resistant bacteria, being the most frequently isolated ARB. Analyzing of ARGs revealed the highest detection of aac6, followed by sul1 gene. However, the β-lactamase genes blaCTX-M and blaTEM were not identified in the ARB, suggesting the presence of other β-lactamase genes not included in the tested panel. Exposure of ARB to free chlorine at a concentration of 0.5 mg/l showed that 64% of the isolates were CRB. However, increasing the chlorine concentration to 4 mg/l decreased the high fraction of ARB (91%). The dominant CRB identified were Sphingomonas, Brevundimonas, Stenotrophomonas, Bacillus and Staphylococcus with Bacillus exhibiting the highest frequency. The results highlight the potential risk of biofilm formation in the DWDS of hospitals, leading to the dissemination of ARB in hospital environments, which is a great concern for the health of hospitalized patients, especially vulnerable individuals. Surveillance of antimicrobial resistance in DWDS of hospitals can provide valuable insights for shaping antimicrobial use policies and practices that ensure their efficacy.
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Affiliation(s)
- Mohammadmehdi Mehdipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Student Research Committee, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sahar Gholipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Farzaneh Mohammadi
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Hatamzadeh
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahnaz Nikaeen
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Diseases, Isfahan University of Medical Sciences, Isfahan, Iran.
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27
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Cong W, Pike A, Gonçalves K, Shisler JL, Mariñas BJ. Inactivation Kinetics and Replication Cycle Inhibition of Coxsackievirus B5 by Free Chlorine. Environ Sci Technol 2023; 57:18690-18699. [PMID: 36946773 DOI: 10.1021/acs.est.2c09269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The kinetics of coxsackievirus serotype B5 (CVB5) inactivation with free chlorine is characterized over a range of pH and temperature relevant to drinking water treatment with the primary goal of selecting experimental conditions used for assessing inactivation mechanisms. The inactivation kinetics identified in our study is similar to or slower than experimental data reported in the literature and thus provides a conservative representation of the kinetics of CVB5 inactivation for free chlorine that could be useful in developing future regulations for waterborne viral pathogens including adequate disinfection treatment for CVB5. Untreated and free chlorine-treated viruses, and host cells synchronized-infected with these viruses, are analyzed by a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) method with the goal of quantitatively investigating the effect of free chlorine exposure on viral genome integrity, attachment to host cell, and viral genome replication. The inactivation kinetics observed results from a combination of hindering virus attachment to the host cell, inhibition of one or more subsequent steps of the replication cycle, and possibly genome damage.
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28
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Wang J, Chen W, Wang T, Reid E, Krall C, Kim J, Zhang T, Xie X, Huang CH. Bacteria and Virus Inactivation: Relative Efficacy and Mechanisms of Peroxyacids and Chlor(am)ine. Environ Sci Technol 2023; 57:18710-18721. [PMID: 36995048 PMCID: PMC10690719 DOI: 10.1021/acs.est.2c09824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/19/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
Peroxyacids (POAs) are a promising alternative to chlorine for reducing the formation of disinfection byproducts. However, their capacity for microbial inactivation and mechanisms of action require further investigation. We evaluated the efficacy of three POAs (performic acid (PFA), peracetic acid (PAA), and perpropionic acid (PPA)) and chlor(am)ine for inactivation of four representative microorganisms (Escherichia coli (Gram-negative bacteria), Staphylococcus epidermidis (Gram-positive bacteria), MS2 bacteriophage (nonenveloped virus), and Φ6 (enveloped virus)) and for reaction rates with biomolecules (amino acids and nucleotides). Bacterial inactivation efficacy (in anaerobic membrane bioreactor (AnMBR) effluent) followed the order of PFA > chlorine > PAA ≈ PPA. Fluorescence microscopic analysis indicated that free chlorine induced surface damage and cell lysis rapidly, whereas POAs led to intracellular oxidative stress through penetrating the intact cell membrane. However, POAs (50 μM) were less effective than chlorine at inactivating viruses, achieving only ∼1-log PFU removal for MS2 and Φ6 after 30 min of reaction in phosphate buffer without genome damage. Results suggest that POAs' unique interaction with bacteria and ineffective viral inactivation could be attributed to their selectivity toward cysteine and methionine through oxygen-transfer reactions and limited reactivity for other biomolecules. These mechanistic insights could inform the application of POAs in water and wastewater treatment.
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Affiliation(s)
- Junyue Wang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Wensi Chen
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Ting Wang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Elliot Reid
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Caroline Krall
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Juhee Kim
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Tianqi Zhang
- School
of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique FÉdÉrale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Xing Xie
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Ching-Hua Huang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Coleman CK, Kim J, Bailey ES, Abebe LS, Brown J, Simmons OD, Sobsey MD. Bromine and Chlorine Disinfection of Cryptosporidium parvum Oocysts, Bacillus atrophaeus Spores, and MS2 Coliphage in Water. Environ Sci Technol 2023; 57:18744-18753. [PMID: 37220325 DOI: 10.1021/acs.est.3c00536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Conventional water treatment practices utilizing chemical disinfection, especially chlorination, are considered generally effective in producing microbiologically safe drinking water. However, protozoan pathogens such as oocysts of Cryptosporidium parvum are very resistant to chlorine, which has led to consideration of alternative disinfectants for their control. Free bromine, HOBr, has not been evaluated extensively as an alternative halogen disinfectant for inactivation of Cryptosporidium parvum in drinking water or reclaimed water for non-potable uses. Bromine is a versatile disinfectant consisting of different chemical forms with persistent microbicidal efficacy under varied water quality conditions and is effective against a range of waterborne microbes of health concern. The objectives of this study are to (1) compare the efficacy of free bromine to free chlorine at similar concentrations (as milligrams per liter) for disinfection of Cryptosporidium parvum oocysts, Bacillus atrophaeus spores, and MS2 coliphage in a model buffered water and (2) evaluate the kinetics of inactivation of these microorganisms using appropriate disinfection models. Overall, at a target concentration of ∼5 mg/L, bromine averaged 0.6 log (73.8%) reductions of C. parvum oocyst infectivity after 300 min (CT: 1166 min·mg/L) and produced up to a 0.8 log reduction disinfectant activity. An ∼5.0 mg/L chlorine dose increased oocyst infectivity by only 0.4 log (64%) after 300 min (CT: 895 min·mg/L). Bacillus atrophaeus spores and MS2 coliphage treated with bromine and chlorine were reduced by 4 log10 (99.99%) for both disinfectants over the duration of the experiments.
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Affiliation(s)
- Collin Knox Coleman
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
| | - John Kim
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
| | - Emily S Bailey
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
| | - Lydia S Abebe
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
| | - Joe Brown
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
| | - Otto D Simmons
- College of Agriculture and Life Sciences, North Carolina State University, Campus Box 7601, NC State University Campus, Raleigh, North Carolina 27695, United States
| | - Mark D Sobsey
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, CB#7431, Chapel Hill, North Carolina 27599, United States
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30
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Torii S, David SC, Larivé O, Cariti F, Kohn T. Observed Kinetics of Enterovirus Inactivation by Free Chlorine Are Host Cell-Dependent. Environ Sci Technol 2023; 57:18483-18490. [PMID: 36649532 DOI: 10.1021/acs.est.2c07048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Virucidal efficacies of disinfectants are typically assessed by infectivity assay utilizing a single type of host cell. Enteroviruses infect multiple host cells via various entry routes, and each entry route may be impaired differently by a given disinfectant. Yet, it is unknown how the choice of host cells affects the observed inactivation kinetics. Here, we evaluated the inactivation kinetics of echovirus 11 (E11) by free chlorine, ultraviolet (UV) irradiation, and heat, using three different host cells (BGMK, RD, and A549). Inactivation rates were independent of the host cell for treatment of E11 by UV or heat. Conversely, E11 inactivation by free chlorine occurred 2-fold faster when enumerated on BGMK cells compared with RD and A549 cells. Host cell-dependent inactivation kinetics by free chlorine were also observed for echovirus 7, 9, and 13, and coxsackievirus A9. E11 inactivation by free chlorine was partly caused by a loss in host cell attachment, which was most pronounced for BGMK cells. BGMK cells lack the attachment receptor CD55 and a key subunit of the uncoating receptor β2M, which may contribute to the differential inactivation kinetics for this cell type. Consequently, inactivation kinetics of enteroviruses should be assessed using host cells with different receptor profiles.
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Affiliation(s)
- Shotaro Torii
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland
| | - Shannon Christa David
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland
| | - Odile Larivé
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland
| | - Federica Cariti
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland
| | - Tamar Kohn
- Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland
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31
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Lundquist NA, Kifelew LG, Elmas S, Jia Z, Speck PG, Chalker JM. Inactivation of human coronaviruses using an automated room disinfection device. Sci Rep 2023; 13:20048. [PMID: 37973822 PMCID: PMC10654563 DOI: 10.1038/s41598-023-47082-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023] Open
Abstract
The emergence of more virulent and epidemic strains of viruses, especially in the context of COVID-19, makes it more important than ever to improve methods of decontamination. The objective of this study was to evaluate the potential of on-demand production of chlorine species to inactivate human coronaviruses. The commercial prototype disinfection unit was provided by Unipolar Water Technologies. The Unipolar device generates active chlorine species using an electrochemical reaction and dispenses the disinfectant vapour onto surfaces with an aspirator. The minimum effective concentration and exposure time of disinfectant were evaluated on human hepatoma (Huh7) cells using 50% tissue culture infectious dose (TCID50) assay and human coronavirus 229E (HCoV-229E), a surrogate for pathogenic human coronaviruses. We showed that chlorine species generated in the Unipolar device inactivate HCoV-229E on glass surfaces at ≥ 400 parts per million active chlorine concentration with a 5 min exposure time. Here, inactivation refers to the inability of the virus to infect the Huh7 cells. Importantly, no toxic effect was observed on Huh7 cells for any of the active chlorine concentrations and contact times tested.
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Affiliation(s)
- Nicholas A Lundquist
- Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Legesse G Kifelew
- Molecular Biosciences, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Sait Elmas
- Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Zhongfan Jia
- Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Peter G Speck
- Molecular Biosciences, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia.
| | - Justin M Chalker
- Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia.
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32
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Wang Y, Sun W, Dong H, Qiang Z. Accelerated degradation of micro-pollutant by combined UV and chlorine dioxide: Unexpected inhibition of chlorite formation. Environ Pollut 2023; 337:122600. [PMID: 37739255 DOI: 10.1016/j.envpol.2023.122600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 08/05/2023] [Accepted: 09/20/2023] [Indexed: 09/24/2023]
Abstract
UV/chlorine dioxide (ClO2) process can be intentionally or accidently conducted and is potentially effective in micro-pollutants degradation. UV irradiation can promote ClO2 decay and subsequently result in the formation of reactive radicals. Hence, the co-exposure of ClO2 and UV exhibited a synergetic effect on metribuzin (MET) degradation. The MET degradation was promoted by UV/ClO2 with a rate of 0.089 min-1 at pH 7.5, which was around 2.4 folds the total of rates caused by single ClO2 (0.004 min-1) and single UV (0.033 min-1). Reactive radicals mainly HO• and reactive chlorine species were involved in the acceleration effect, and contributed to 59%-67% of the total degradation rate of MET during UV/ClO2 under pHs 5.5-7.5. Among them, HO• was the predominant contributor and the contribution rate gradually rose under higher pH. Chlorite (ClO2-) and chlorate (ClO3-) formation has been the major concern of ClO2 oxidation. However, a comparison of their formation during UV/ClO2 and ClO2 oxidation is rarely reported. Herein, during MET degradation by ClO2, only ClO2- was identified with the highest amount of 1.17 mg L-1. Conversely, during MET degradation by UV/ClO2, only ClO3- was identified with the highest amount of 0.68 mg L-1, showing an upward trend with prolonging treatment time. Furthermore, organic halogenated DBPs formation after 24 h post-chlorination with UV/ClO2 and ClO2 pre-treatments was comparatively evaluated. Organic DBPs formation after post-chlorination was higher with UV/ClO2 pre-treatment compared to ClO2 pre-treatment. The overall concentration of DBPs produced with 30 min UV/ClO2 pre-treatment was about 4.5 times that with 1min UV/ClO2 pre-treatment. This study provided useful reference for the application of UV/ClO2 in micro-pollutants degradation.
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Affiliation(s)
- Yan Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wenyu Sun
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing, 100085, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing, 100101, China
| | - Huiyu Dong
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Zhimin Qiang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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Murphy CM, Hamilton AM, Waterman K, Rock C, Schaffner DW, Strawn LK. Efficacy of Peracetic Acid and Chlorine on the Reduction of Shiga Toxin-producing Escherichia coli and a Nonpathogenic E. coli Strain in Preharvest Agricultural Water. J Food Prot 2023; 86:100172. [PMID: 37783289 DOI: 10.1016/j.jfp.2023.100172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/24/2023] [Accepted: 09/27/2023] [Indexed: 10/04/2023]
Abstract
Produce-borne outbreaks of Shiga toxin-producing Escherichia coli (STEC) linked to preharvest water emphasize the need for efficacious water treatment options. This study quantified reductions of STEC and generic E. coli in preharvest agricultural water using commercially available sanitizers. Water was collected from two sources in Virginia (pond, river) and inoculated with either a seven-strain STEC panel or environmental generic E. coli strain TVS 353 (∼9 log10 CFU/100 mL). Triplicate inoculated water samples were equilibrated to 12 or 32°C and treated with peracetic acid (PAA) or chlorine (Cl) [low (PAA:6ppm, Cl:2-4 ppm) or high (PAA:10 ppm, Cl:10-12 ppm) residual concentrations] for an allotted contact time (1, 5, or 10 min). Strains were enumerated, and a log-linear model was used to characterize how treatment combinations influenced reductions. All Cl treatment combinations achieved a ≥3 log10 CFU/100 mL reduction, regardless of strain (3.43 ± 0.25 to 7.05 ± 0.00 log10 CFU/100 mL). Approximately 80% (19/24) and 67% (16/24) of PAA treatment combinations achieved a ≥3 log10 CFU/100 mL for STEC and E. coli TVS 353, respectively. The log-linear model showed contact time (10 > 5 > 1 min) and sanitizer type (Cl > PAA) had the greatest impact on STEC and E. coli TVS 353 reductions (p < 0.001). E. coli TVS 353 in water samples was more resistant to sanitizer treatment (p < 0.001) indicating applicability as a good surrogate. Results demonstrated Cl and PAA can be effective agricultural water treatment strategies when sanitizer chemistry is managed. These data will assist with the development of in-field validation studies and may identify suitable candidates for the registration of antimicrobial pesticide products for use against foodborne pathogens in preharvest agricultural water treatment.
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Affiliation(s)
- Claire M Murphy
- Department of Food Science and Technology, Virginia Tech, Blacksburg, VA, USA; School of Food Science, Washington State University - Irrigated Agriculture Research and Extension Center, Prosser, WA, USA
| | - Alexis M Hamilton
- Department of Food Science and Technology, Virginia Tech, Blacksburg, VA, USA
| | - Kim Waterman
- Department of Food Science and Technology, Virginia Tech, Blacksburg, VA, USA
| | - Channah Rock
- Department of Environmental Science, University of Arizona - Maricopa Agricultural Center, Maricopa, AZ, USA
| | - Donald W Schaffner
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Laura K Strawn
- Department of Food Science and Technology, Virginia Tech, Blacksburg, VA, USA.
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34
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Shi Q, Chen Z, Yan H, Xu M, Cao KF, Mao Y, Chen X, Hu HY. Identification of significant live bacterial community shifts in different reclaimed waters during ozone and chlorine disinfection. Sci Total Environ 2023; 896:165199. [PMID: 37391159 DOI: 10.1016/j.scitotenv.2023.165199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/12/2023] [Accepted: 06/27/2023] [Indexed: 07/02/2023]
Abstract
Ozone and chlorine are the most widely used disinfectants for water and wastewater disinfection. They play important role in microbial inactivation but could also pose a considerable selection effect on the microbial community of reclaimed water. Classical culture-based methods that rely on the assessment of conventional bacterial indicators (e.g., coliform bacteria) could hardly reflect the survival of disinfection residual bacteria (DRB) and hidden microbial risks in disinfected effluents. Hence, this study investigated the shifts of live bacterial community during ozone and chlorine disinfection in three reclaimed waters (i.e., two secondary effluents and one tertiary effluent), adopting Illumina Miseq sequencing technology in combination with a viability assay, propidium monoazide (PMA) pretreatment. Notably, statistical analyses of Wilcoxon rank-sum test confirmed the existance of distinct differences in bacterial community structure between samples with or without PMA pretreatment. On the phylum level, Proteobacteria commonly dominated in three undisinfected reclaimed waters, while ozone and chlorine disinfection posed varied effects on its relative abundance among different influents. On the genus level, ozone and chlorine disinfection significantly changed the bacterial composition and dominant species in reclaimed waters. Specifically, the typical DRB identified in ozone disinfected effluents were Pseudomonas, Nitrospira and Dechloromonas, while for chlorine disinfected effluents, Pseudomonas, Legionella, Clostridium, Mycobacterium and Romboutsia were recognized as typical DRB, which call for much attention. The Alpha and Beta diversity analysis results also suggested that different influent compositions greatly affected the bacterial community structure during disinfection processes. Since the experiments in present study were conducted in a short period and the dataset was relatively limited, prolonged experiment under different operational conditions are needed in future to illustrate the potential long-term effects of disinfection on the microbial community structure. The findings of this study could provide insights into microbial safety concern and control after disinfection for sustainable water reclamation and reuse.
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Affiliation(s)
- Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Han Yan
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Meiying Xu
- State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China
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Wang M, Wang H, Hu C, Deng J, Shi B. Phthalate acid esters promoted the enrichment of chlorine dioxide-resistant bacteria and their functions related to human diseases in rural polyvinyl chloride distribution pipes. Sci Total Environ 2023; 896:165282. [PMID: 37406691 DOI: 10.1016/j.scitotenv.2023.165282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/09/2023] [Accepted: 07/01/2023] [Indexed: 07/07/2023]
Abstract
Polyvinyl chloride (PVC) pipes are widely used as drinking water distribution pipes in rural areas of China. However, whether phthalate acid esters (PAEs) released from PVC pipes will affect tap water quality is still unknown. The influence of released PAEs on the water quality was analysed in this study, especially after ClO2 disinfection. The results indicated that ClO2 disinfection could control the growth of total coliforms and heterotrophic bacteria (HPC). However, when the ClO2 residual decreased to below 0.10 mg/L, HPC and opportunistic pathogens, including Mycobacterium avium and Pseudomonas aeruginosa, increased significantly. In addition, after ClO2 disinfection, PAEs concentrations increased from 10.6-22.2 μg/L to 21.2-58.8 μg/L in different sampling cites. Linear discriminant analysis (LDA) effect size (LEfSe) and statistical analysis of metagenomic profiles (Stamp) showed that ClO2 disinfection induced the enrichment of Pseudomonas, Bradyrhizobium, and Mycobacterium and functions related to human diseases, such as pathogenic Escherichia coli infection, shigellosis, Staphylococcus aureus infection, and Vibrio cholerae infection. The released PAEs not only promoted the growth of these ClO2-resistant bacterial genera but also enhanced their functions related to human diseases. Moreover, these PAEs also induced the enrichment of other bacterial genera, such as Blastomonas, Dechloromonas, and Kocuria, and their functions, such as chronic myeloid leukaemia, African trypanosomiasis, leishmaniasis, hepatitis C and human T-cell leukaemia virus 1 infection. The released PAEs enhanced the microbial risk of the drinking water. These results are meaningful for guaranteeing water quality in rural areas of China.
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Affiliation(s)
- Min Wang
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Chisheng Hu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianmian Deng
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China.
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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36
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Ouyang QW, Long J, Hao HC, Wang WY, Li Y, Huang YH, Hou HB, Peng PQ. [Effects of Chlorine-based and Sulfur-based Fertilizers on Rice Bioavailability of Cd in Soils]. Huan Jing Ke Xue 2023; 44:5737-5745. [PMID: 37827789 DOI: 10.13227/j.hjkx.202209279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
To explore the effects of single or combined application of chlorine-and sulfur-based fertilizers on rice bioavailability of Cd in soils, pot experiments with reddish clayey soil (developed from quaternary red clay parent materials) under three exogenous Cd levels (0, 0.5, and 2.0 mg·kg-1) were conducted. Meanwhile, chlorine-based fertilizers (KCl, NH4Cl) and sulfur-based fertilizers[K2SO4, (NH4)2SO4] were added in different proportions. The soil pH, Cd morphology, and Cd accumulation in rice at different growth stages were analyzed. The results revealed that both chlorine-and sulfur-based fertilizers could acidify the soil; however, the effect of chlorine-based fertilizers was more significant. During the filling stage of rice, the soil pH value of the treatment of applying single chlorine-based fertilizer decreased by 0.28 on average compared with that of applying single sulfur-based fertilizer. At the maturity stage of rice, chlorine-based fertilizer could activate the residual Cd, whereas sulfur-based fertilizer passivated the acid-extracted Cd to its residual state. Compared with the single application of the same fertilizer, the combined application of chlorine-and sulfur-based fertilizers was more likely to promote the accumulation of Cd in rice plants. The highest Cd accumulation of brown rice was 0.21 mg·kg-1 (2.0 mg·kg-1 exogenous Cd level) in the 1:1 (mole ratios of Cl:S) treatment of chlorine-and sulfur-based fertilizers, which was 16.4% higher than that of single chlorine-based fertilizer and 113.3% higher than that of single sulfur-based fertilizer. Therefore, the combined application of chlorine-fertilizers and sulfur-based fertilizers will increase the concentration of Cd in brown rice. To ensure food quality and safety, it is more advisable to apply single sulfur-based fertilizer for rice planting.
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Affiliation(s)
- Qing-Wen Ouyang
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Jian Long
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China
| | - Han-Chi Hao
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Wen-Yu Wang
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yao Li
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yi-Hang Huang
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Hong-Bo Hou
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China
| | - Pei-Qin Peng
- College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- Hunan Engineering Laboratory for Control of Rice Quality and Safety, Changsha 410004, China
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Rolbiecki D, Paukszto Ł, Krawczyk K, Korzeniewska E, Sawicki J, Harnisz M. Chlorine disinfection modifies the microbiome, resistome and mobilome of hospital wastewater - A nanopore long-read metagenomic approach. J Hazard Mater 2023; 459:132298. [PMID: 37595469 DOI: 10.1016/j.jhazmat.2023.132298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 08/04/2023] [Accepted: 08/12/2023] [Indexed: 08/20/2023]
Abstract
The aim of the present study was to analyze changes in the microbiome, resistome, and mobilome of hospital wastewater (HWW) induced by disinfection with chlorine compounds. Changes in bacterial communities and specific antibiotic resistance genes (ARGs) in HWW were determined with the use of a nanopore long-read metagenomic approach. The main hosts of ARGs in HWW were identified, and the mobility of resistance mechanisms was analyzed. Special attention was paid to the prevalence of critical-priority pathogens in the HWW microbiome, which pose the greatest threat to human health. The results of this study indicate that chlorine disinfection of HWW can induce significant changes in the structure of the total bacterial population and antibiotic resistant bacteria (ARB) communities, and that it can modify the resistome and mobilome of HWW. Disinfection favored the selection of ARGs, decreased their prevalence in HWW, while increasing their diversity. The mobility of the HWW resistome increased after disinfection. Disinfection led to the emergence of new drug resistance mechanisms in previously sensitive bacterial taxa. In conclusion, this study demonstrated that HWW disinfected with low (sublethal) concentrations of free chlorine significantly contributes to the mobility and transfer of drug resistance mechanisms (including critical mechanisms) between bacteria (including pathogens).
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Affiliation(s)
- Damian Rolbiecki
- Department of Water Protection Engineering and Environmental Microbiology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Poland
| | - Łukasz Paukszto
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Poland
| | - Katarzyna Krawczyk
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Poland
| | - Ewa Korzeniewska
- Department of Water Protection Engineering and Environmental Microbiology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Poland
| | - Jakub Sawicki
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Poland
| | - Monika Harnisz
- Department of Water Protection Engineering and Environmental Microbiology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Poland.
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Dang C, Zhang Y, Zheng M, Meng Q, Wang J, Zhong Y, Wu Z, Liu B, Fu J. Effect of chlorine disinfectant influx on biological sewage treatment process under the COVID-19 pandemic: Performance, mechanisms and implications. Water Res 2023; 244:120453. [PMID: 37572464 DOI: 10.1016/j.watres.2023.120453] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 07/12/2023] [Accepted: 08/05/2023] [Indexed: 08/14/2023]
Abstract
Since the onset of the COVID-19 Pandemic, large amounts of chlorine-containing disinfectants have been used to interrupt the spread of SARS-CoV-2 and residual chlorine eventually entered the hospital or municipal sewage treatment facilities. However, little is known about the effect of chlorine influx on the biological sewage treatment process. Here we investigated the effect of chlorine on the microbiome and the mechanism of microbial chlorine resistance in the activated sludge of the aerobic treatment process, using metagenomic and metatranscriptomic sequencing. We found that chlorine could negatively impact the aerobic treatment performance regarding nitrogen/COD removal with a dose-dependent effect, and the dual effects of chlorine dose and interaction time differentiated the microbial community in activated sludge. The decline of nitrogen/COD removal was attributed to the compressed activity of functional microorganisms, such as the ammonia oxidation bacteria, under chlorinated conditions, and the damage cannot be recovered in a short term. In addition, some microorganisms could survive in chlorinated conditions by up-regulating the chlorine resistance genes (CRGs) expression (approximately 1.5 times) and stimulating new CRGs expression. In particular, species Acinetobacter johnsonii could resist high concentrations of chlorine through various mechanisms, especially the overexpression of efflux pump function encoded by qac genes play a key role. Based on these results, considering the persistence of the epidemic and extensive use of chlorine disinfectants, it cannot be ignored that large amounts of residual chlorine are entering the biological treatment facility, and strictly de-chlorination measures or microbial chlorine resistance regulations before entering should be implemented.
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Affiliation(s)
- Chenyuan Dang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yibo Zhang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Maosheng Zheng
- College of Environmental Science and Engineering, The Key Laboratory of Resources and Environmental Systems Optimization, North China Electric Power University, Ministry of Education, Beijing 102206, China
| | - Qiyue Meng
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jia Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Yuening Zhong
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zhenbing Wu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bingchuan Liu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jie Fu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
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Xu YQ, Wu YH, Luo LW, Huang BH, Chen Z, Wang HB, Liu H, Ikuno N, Koji N, Hu HY. Inactivation of chlorine-resistant bacteria (CRB) via various disinfection methods: Resistance mechanism and relation with carbon source metabolism. Water Res 2023; 244:120531. [PMID: 37659185 DOI: 10.1016/j.watres.2023.120531] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/22/2023] [Accepted: 08/25/2023] [Indexed: 09/04/2023]
Abstract
With the widespread use of chlorine disinfection, chlorine-resistant bacteria (CRB) in water treatment systems have gained public attention. Bacterial chlorine resistance has been found positively correlated with extracellular polymeric substance (EPS) secretion. In this study, we selected the most suitable CRB controlling method against eight bacterial strains with different chlorine resistance among chloramine, ozone, and ultraviolet (UV) disinfection, analyzed the resistance mechanisms, clarified the contribution of EPS to disinfection resistance, and explored the role of carbon source metabolism capacity. Among all the disinfectants, UV disinfection showed the highest disinfection capacity by achieving the highest average and median log inactivation rates for the tested strains. For Bacillus cereus CR19, the strain with the highest chlorine resistance, 40 mJ/cm2 UV showed a 1.90 log inactivation, which was much higher than that of 2 mg-Cl2/L chlorine (0.67 log), 2 mg-Cl2/L chloramine (1.68 log), and 2 mg/L ozone (0.19 log). Meanwhile, the UV resistance of the bacteria did not correlate with EPS secretion. These characteristics render UV irradiation the best CRB controlling disinfection method. Chloramine was found to have a generally high inactivation efficiency for bacteria with high chlorine-resistance, but a low inactivation efficiency for low chlorine-resistant ones. Although EPS consumed up to 56.7% of chloramine which an intact bacterial cell consumed, EPS secretion could not explain chloramine resistance. Thus, chloramine is an acceptable CRB control method. Similar to chlorine, ozone generally selected high EPS-secreting bacteria, with EPS consuming up to 100% ozone. Therefore, ozone is not an appropriate method for controlling CRB with high EPS secretion. EPS played an important role in all types of disinfection resistance, and can be considered the main mechanism for bacterial chlorine and ozone disinfection resistance. However, as EPS was not the main resistance mechanism in UV and chloramine disinfection, CRB with high EPS secretion were inactivated more effectively. Furthermore, carbon source metabolism was found related to the multiple resistance of bacteria. Those with low carbon source metabolism capacity tended to have higher multiple resistance, especially to chlorine, ozone, and UV light. Distinctively, among the tested gram-negative bacteria, in contrast to other disinfectants, chloramine resistance was negatively correlated with EPS secretion and positively correlated with carbon source metabolism capacity, suggesting a special disinfection mechanism.
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Affiliation(s)
- Yu-Qing Xu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Bang-Hao Huang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Han Liu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Nakata Koji
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, Jiangsu 215163, PR China
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40
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Chen X, Chen Z, Ngo HH, Mao Y, Cao K, Shi Q, Lu Y, Hu HY. Comparison of inactivation characteristics between Gram-positive and Gram-negative bacteria in water by synergistic UV and chlorine disinfection. Environ Pollut 2023; 333:122007. [PMID: 37302789 DOI: 10.1016/j.envpol.2023.122007] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/23/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Disinfection is essential in water and wastewater treatment process as a guarantee for microbial safety. This study systematically investigated: (i) the inactivation characteristics of bacteria widely existed in water, including Gram-negative bacteria (Escherichiacoli) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis spores), by sequential UV and chlorine disinfection processes (UV-Cl and Cl-UV), simultaneous UV and chlorine disinfection process (UV/Cl); and (ii) the disinfection mechanisms on different bacteria. The combination of UV and chlorine disinfection could inactive bacteria at lower doses, but showed no synergistic effect on E. coli. Contrarily, disinfection results indicated that UV/Cl performed an obvious synergistic effect on highly disinfectant-resistant bacteria (e.g. S. aureus and B. subtilis spores). Specifically, UV/Cl at the UV dose of 9 mJ/cm2 and chlorine dose of 2 mg-Cl/L could inactivate S. aureus completely. Moreover, the effectiveness of UV/Cl on the removal of indigenous bacteria in actual water conditions was also confirmed. In short, the study provides significant theoretical and practical implications for ensuring microbial safety during water treatment and use.
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Affiliation(s)
- Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Kefan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China
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41
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Gensler C, Harper K, Stoufer S, Moore MD, Kinchla AJ, McLandsborough L. Exploring Washing Procedures for Produce Brush Washer. J Food Prot 2023; 86:100126. [PMID: 37414285 DOI: 10.1016/j.jfp.2023.100126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 06/13/2023] [Accepted: 06/30/2023] [Indexed: 07/08/2023]
Abstract
Previous environmental monitoring projects in food production facilities have revealed inconsistencies in how produce brush washer machines are cleaned after use; thus, the study of effective sanitation procedures for these machines is needed. Four chlorine solution treatments (ranging from 25 to 200 ppm), as well as a water-only treatment, were tested for efficacy in reducing bacterial loads for a selected small brush washer machine. Results indicate that rinsing with the machine's power and water alone, a frequent practice among some produce processors, yielded a reduction of 0.91-1.96 log CFU per brush roller in bacterial counts, which was not statistically significant (p > 0.05). However, the chlorine treatments were found to be effective in reducing bacterial loads significantly, with higher concentrations being the most effective. The 200 ppm and 100 ppm chlorine treatments yielded bacterial reductions of 4.08 and 3.95 log CFU per brush roller, respectively, leaving bacterial levels statistically similar to the levels at postprocess decontamination, meaning these are the most effective at killing bacteria of all the chlorine concentrations tested. These data suggest the use of at least 100 ppm chlorine sanitizer solution is a good method to sanitize hard-to-clean produce washing machines, yielding an approximate 4 log CFU reduction of the inoculated bacteria.
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Affiliation(s)
- Catherine Gensler
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
| | - Kelsi Harper
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
| | - Sloane Stoufer
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
| | - Matthew D Moore
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
| | - Amanda J Kinchla
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA.
| | - Lynne McLandsborough
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
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42
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Sherchan S, Ikner LA, Gerba CP. Inactivation of SARS-CoV-2 in Water by Chlorination. Food Environ Virol 2023; 15:262-264. [PMID: 37421543 DOI: 10.1007/s12560-023-09559-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 06/19/2023] [Indexed: 07/10/2023]
Abstract
Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is present in both respiratory secretions and feces, creating its potential for transmission by swimming pools. Recreational water activity is known to be at increased risk of respiratory infections and respiratory viruses have caused been detected and have caused outbreaks in swimming pools. However, little is known regarding the chlorine inactivation of SARS-CoV-2 in water typical of swimming pools in the USA. In this study, the inactivation of SARS-CoV-2 Isolate hCoV-19/USA-WA1/2020 was observed in water by chlorination. All experiments were conducted within a BSL-3 laboratory at room temperature. Our results show that the virus was reduced by 3.5 log (> 99.9%) after 30 s of 2.05-mg/L free chlorine contact and greater than 4.17 log (limit of detection) (> 99.99%) within 2 min.
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Affiliation(s)
- Samendra Sherchan
- Department of Environmental Health Sciences, Tulane University, New Orleans, LA, 70112, USA.
- BioEnvironmental Science Program, Morgan State University, Baltimore, MD, 21251, USA.
| | - Luisa A Ikner
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
| | - Charles P Gerba
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
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43
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He G, Fatona A, Tian L, Song C, Liu J, Fefer M, Hosseinidoust Z, Pelton RH. Impacts of non-microbial soils on polychloramide disinfectants. Colloids Surf B Biointerfaces 2023; 229:113464. [PMID: 37478543 DOI: 10.1016/j.colsurfb.2023.113464] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/30/2023] [Accepted: 07/16/2023] [Indexed: 07/23/2023]
Abstract
The presence of some nonmicrobial chemicals and surfaces, herein called "soils", are known to degrade the performance of biocides, and biocidal assays often include mixtures of materials to mimic the effects of soils. We hypothesized that water-soluble anionic polychloramide biocides were less sensitive to soil interference than cationic polymeric biocides. The relationships between soil composition and antimicrobial polymer biocidal activity were compared for an anionic polychloramide, a cationic polychloramide, and a cationic poly(quaternary ammonium) biocide. The nanoscale soil models individually investigated were polyacrylic acid (PAA), cellulose nanocrystals (CNCs), and bovine serum albumin. The low molecular weight model soils were ammonium chloride, glycine, and succinimide. Three types of soil impacts were identified: 1) sequestration, whereby the soil physically inhibited transport of the biocide to microbes; 2) extraction, whereby the soil reduced or extracted oxidative chlorine, decreasing or eliminating the oxidative chlorine strength; and 3) extraction whereby the biocidal activity increases in the presence of a low molecular weight chemical that carries oxidative Cl from the polymer to the microbes. PAA and CNCs inhibit cationic biocides by sequestration but have little impact on anionic polychloramide. Glycine and BSA extract oxidative chlorine, lowering the biocidal activity of the anionic and cationic polychloramides while not impacting the poly(quaternary ammonium) biocide. Finally, the presence of succinimide increased bacteria deactivation of both anionic and cationic polychloramides. We propose that succinimide extracts oxidative chlorine from the polychloramides and transports it to the bacteria.
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Affiliation(s)
- Gaoyin He
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
| | - Ayodele Fatona
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
| | - Lei Tian
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
| | - Chaochen Song
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
| | - Jun Liu
- Suncor AgroScience, 2489 North Sheridan Way, Mississauga, Ontario L5K 1A8, Canada
| | - Michael Fefer
- Suncor AgroScience, 2489 North Sheridan Way, Mississauga, Ontario L5K 1A8, Canada
| | - Zeinab Hosseinidoust
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada
| | - Robert H Pelton
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario L8S 4L7, Canada.
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44
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Canh VD, Torii S, Singhopon T, Katayama H. Inactivation of coxsackievirus B5 by free chlorine under conditions relevant to drinking water treatment. J Water Health 2023; 21:1318-1324. [PMID: 37756198 PMCID: wh_2023_178 DOI: 10.2166/wh.2023.178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Chlorine disinfection is commonly applied to inactivate pathogenic viruses in drinking water treatment plants. However, the role of water quality in chlorine disinfection of viruses has not been investigated thoughtfully. In this study, we investigated the inactivation efficiency of coxsackievirus B5 (CVB5) by free chlorine using actual water samples collected from four full-scale drinking water treatment plants in Japan under strict turbidity management (less than 0.14 NTU) over a 12-month period. It was found that chlorine disinfection of CVB5 might not be affected by water quality. Japanese turbidity management might play an indirect role in controlling the efficiency of chlorine disinfection.
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Affiliation(s)
- Vu Duc Canh
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan E-mail:
| | - Shotaro Torii
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan; Laboratory of Environmental Chemistry, School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique F ́ed ́erale de Lausanne (EPFL), Lausanne, Switzerland
| | - Tippawan Singhopon
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroyuki Katayama
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan; Research Center for Water Environment Technology, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
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45
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Murphy CM, Hamilton AM, Waterman K, Rock C, Schaffner D, Strawn LK. Sanitizer Type and Contact Time Influence Salmonella Reductions in Preharvest Agricultural Water Used on Virginia Farms. J Food Prot 2023; 86:100110. [PMID: 37268194 DOI: 10.1016/j.jfp.2023.100110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/04/2023]
Abstract
No Environmental Protection Agency (EPA) chemical treatments for preharvest agricultural water are currently labeled to reduce human health pathogens. The goal of this study was to examine the efficacy of peracetic acid- (PAA) and chlorine (Cl)-based sanitizers against Salmonella in Virginia irrigation water. Water samples (100 mL) were collected at three time points during the growing season (May, July, September) and inoculated with either the 7-strain EPA/FDA-prescribed cocktail or a 5-strain Salmonella produce-borne outbreak cocktail. Experiments were conducted in triplicate for 288 unique combinations of time point, residual sanitizer concentration (low: PAA, 6 ppm; Cl, 2-4 ppm or high: PAA, 10 ppm; Cl, 10-12 ppm), water type (pond, river), water temperature (12°C, 32°C), and contact time (1, 5, 10 min). Salmonella were enumerated after each treatment combination and reductions were calculated. A log-linear model was used to characterize how treatment combinations influenced Salmonella reductions. Salmonella reductions by PAA and Cl ranged from 0.0 ± 0.1 to 5.6 ± 1.3 log10 CFU/100 mL and 2.1 ± 0.2 to 7.1 ± 0.2 log10 CFU/100 mL, respectively. Physicochemical parameters significantly varied by untreated water type; however, Salmonella reductions did not (p = 0.14), likely due to adjusting the sanitizer amounts needed to achieve the target residual concentrations regardless of source water quality. Significant differences (p < 0.05) in Salmonella reductions were observed for treatment combinations, with sanitizer (Cl > PAA) and contact time (10 > 5 > 1 min) having the greatest effects. The log-linear model also revealed that outbreak strains were more treatment-resistant. Results demonstrate that certain treatment combinations with PAA- and Cl-based sanitizers were effective at reducing Salmonella populations in preharvest agricultural water. Awareness and monitoring of water quality parameters are essential for ensuring adequate dosing for the effective treatment of preharvest agricultural water.
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Affiliation(s)
- Claire M Murphy
- Department of Food Science and Technology, Virginia Tech, Blacksburg, Virginia, USA
| | - Alexis M Hamilton
- Department of Food Science and Technology, Virginia Tech, Blacksburg, Virginia, USA
| | - Kim Waterman
- Department of Food Science and Technology, Virginia Tech, Blacksburg, Virginia, USA
| | - Channah Rock
- Department of Environmental Science, University of Arizona - Maricopa Agricultural Center, Maricopa, Arizona, USA
| | - Donald Schaffner
- Department of Food Science, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Laura K Strawn
- Department of Food Science and Technology, Virginia Tech, Blacksburg, Virginia, USA.
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46
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Oliveira IM, Gomes IB, Plácido A, Simões LC, Eaton P, Simões M. The impact of potassium peroxymonosulphate and chlorinated cyanurates on biofilms of Stenotrophomonas maltophilia: effects on biofilm control, regrowth, and mechanical properties. Biofouling 2023; 39:691-705. [PMID: 37811587 DOI: 10.1080/08927014.2023.2254704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 08/27/2023] [Indexed: 10/10/2023]
Abstract
The activity of two chlorinated isocyanurates (NaDCC and TCCA) and peroxymonosulphate (OXONE) was evaluated against biofilms of Stenotrophomonas maltophilia, an emerging pathogen isolated from drinking water (DW), and for the prevention of biofilm regrowth. After disinfection of pre-formed 48 h-old biofilms, the culturability was reduced up to 7 log, with OXONE, TCCA, and NaDCC showing more efficiency than free chlorine against biofilms formed on stainless steel. The regrowth of biofilms previously exposed to OXONE was reduced by 5 and 4 log CFU cm-2 in comparison to the unexposed biofilms and biofilms exposed to free chlorine, respectively. Rheometry analysis showed that biofilms presented properties of viscoelastic solid materials, regardless of the treatment. OXONE reduced the cohesiveness of the biofilm, given the significant decrease in the complex shear modulus (G*). AFM analysis revealed that biofilms had a fractured appearance and smaller bacterial aggregates dispersed throughout the surface after OXONE exposure than the control sample. In general, OXONE has been demonstrated to be a promising disinfectant to control DW biofilms, with a higher activity than chlorine. The results also show the impact of the biofilm mechanical properties on the efficacy of the disinfectants in biofilm control.
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Affiliation(s)
- I M Oliveira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - I B Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - A Plácido
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
| | - L C Simões
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, Braga/Guimarães, Portugal
| | - P Eaton
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
- The Bridge, School of Chemistry, University of Lincoln, Lincoln, UK
| | - M Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
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47
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Lawal-Ayinde BM, Morita T, Oda K, Nazmul T, Kurose M, Nomura T, Yamamoto A, Higashiura A, Akita T, Tanaka J, Horiuchi I, Goda H, Sakaguchi T. Virus purification highlights the high susceptibility of SARS-CoV-2 to a chlorine-based disinfectant, chlorous acid. PLoS One 2023; 18:e0288634. [PMID: 37450488 PMCID: PMC10348549 DOI: 10.1371/journal.pone.0288634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 07/01/2023] [Indexed: 07/18/2023] Open
Abstract
Chlorous acid water (HClO2) is known for its antimicrobial activity. In this study, we attempted to accurately assess the ability of chlorous acid water to inactivate SARS-CoV-2. When using cell culture supernatants of infected cells as the test virus, the 99% inactivation concentration (IC99) for the SARS-CoV-2 D614G variant, as well as the Delta and Omicron variants, was approximately 10ppm of free chlorine concentration with a reaction time of 10 minutes. On the other hand, in experiments using a more purified virus, the IC99 of chlorous acid water was 0.41-0.74ppm with a reaction time of 1 minute, showing a strong inactivation capacity over 200 times. With sodium hypochlorite water, the IC99 was 0.54ppm, confirming that these chlorine compounds have a potent inactivation effect against SARS-CoV-2. However, it became clear that when using cell culture supernatants of infected cells as the test virus, the effect is masked by impurities such as amino acids contained therein. Also, when proteins (0.5% polypeptone, or 0.3% BSA + 0.3% sheep red blood cells, or 5% FBS) were added to the purified virus, the IC99 values became high, ranging from 5.3 to 76ppm with a reaction time of 10 minutes, significantly reducing the effect. However, considering that the usual usage concentration is 200ppm, it was shown that chlorous acid water can still exert sufficient disinfection effects even in the presence of proteins. Further research is needed to confirm the practical applications and effects of chlorous acid water, but it has the potential to be an important tool for preventing the spread of SARS-CoV-2.
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Affiliation(s)
| | - Tomoko Morita
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Kosuke Oda
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tanuza Nazmul
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Miuko Kurose
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Toshihito Nomura
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
- Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan
| | - Akima Yamamoto
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Akifumi Higashiura
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Tomoyuki Akita
- Department of Epidemiology, Infectious Disease Control, and Prevention, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | - Junko Tanaka
- Department of Epidemiology, Infectious Disease Control, and Prevention, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | | | | | - Takemasa Sakaguchi
- Department of Virology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
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Zhang H, Zhao D, Ma M, Huang T, Li H, Ni T, Liu X, Ma B, Zhang Y, Li X, Lei X, Jin Y. Actinobacteria produce taste and odor in drinking water reservoir: Community composition dynamics, co-occurrence and inactivation models. J Hazard Mater 2023; 453:131429. [PMID: 37099929 DOI: 10.1016/j.jhazmat.2023.131429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/19/2023] [Accepted: 04/14/2023] [Indexed: 05/03/2023]
Abstract
Taste and odor (T&O) has become a significant concern for drinking water safety. Actinobacteria are believed to produce T&O during the non-algal bloom period; however, this has not been widely investigated. In this study, the seasonal dynamics of the actinobacterial community structure and inactivation of odor-producing actinobacteria were explored. The results indicated that the diversity and community composition of actinobacteria exhibited significant spatiotemporal distribution. Network analysis and structural equation modeling showed that the actinobacterial community occupied a similar environmental niche, and the major environmental attributes exhibited spatiotemporal dynamics, which affected the actinobacterial community. Furthermore, the two genera of odorous actinobacteria were inactivated in drinking water sources using chlorine. Amycolatopsis spp. have a stronger chlorine resistance ability than Streptomyces spp., indicating that chlorine inactivates actinobacteria by first destroying cell membranes and causing the release of intracellular compounds. Finally, we integrated the observed variability in the inactivation rate of actinobacteria into an expanded Chick-Watson model to estimate its effect on inactivation. These findings will deepen our understanding of the seasonal dynamics of actinobacterial community structure in drinking water reservoirs and provide a foundation for reservoir water quality management strategies.
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Affiliation(s)
- Haihan Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Daijuan Zhao
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Manli Ma
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Haiyun Li
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tongchao Ni
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiang Liu
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Ben Ma
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yinbin Zhang
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - Xuan Li
- College of Environmental Science & Engineering, Yancheng Institute of Technology, Yancheng 224051, China
| | - Xiaohui Lei
- Department of Rehabilitation, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - Yaofeng Jin
- Department of Pathology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
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49
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Zhai X, Zhou Y, Song B, Pan W, Wang J. Comparative study on the inhibiting effect of dissolvable tiny-foam extinguishing agent and chlorine salts on coal spontaneous combustion. Environ Sci Pollut Res Int 2023; 30:80591-80601. [PMID: 37296254 DOI: 10.1007/s11356-023-27948-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
Coal spontaneous combustion (CSC) is a global disaster and detrimental to the ecological environment. This study aims to better apply environmentally friendly dissolvable tiny-foam extinguisher (DTE) to CSC and look further into the inhibition mechanism. Thermogravimetric analysis and differential scanning calorimetry (TG-DSC) were employed to test the oxidation properties of coal samples treated with DTE, NaCl, MgCl2, and CaCl2 inhibitors, and the reaction mechanisms and kinetic parameters in the high-temperature stage of coal oxidation were determined. The results revealed that the inhibition of the four inhibitors was similar in the initial period of the coal oxidation, DTE increased the cracking temperature of the coal by 37 °C, mass loss was a minimum when reaching the ignition temperature, and inhibition was better than the other inhibitors at the low temperature. DTE had higher thermal stability and played a stable role in suppression at the high temperature, while chlorine salt inhibitors promoted the oxidative exothermic reaction. DTE coal sample absorbed forty times more heat during the endothermic stage than raw coal, ten times more than MgCl2, and released a minimum of heat. In the decomposition and combustion stages, the reaction mechanism of coal and oxygen conformed to the three-dimensional diffusion Z.-L.-T. equation, and the apparent activation energy of the DTE-treated coal sample was about 40 kJ/mol higher than raw coal.
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Affiliation(s)
- Xiaowei Zhai
- School of Safety Science and Engineering, Xi'an University of Science and Technology, 58, Yanta Mid. Rd, Xi'an, 710054, Shaanxi, China.
- Key Laboratory of Coal Fire Disaster Prevention and Control in Shaanxi Province, Xi'an, 710054, Shaanxi, China.
- Mine Emergency Rescue Innovation Team, The Youth Innovation Team of Shaanxi Universities, Shaanxi, China.
| | - Yujie Zhou
- School of Safety Science and Engineering, Xi'an University of Science and Technology, 58, Yanta Mid. Rd, Xi'an, 710054, Shaanxi, China
- Key Laboratory of Coal Fire Disaster Prevention and Control in Shaanxi Province, Xi'an, 710054, Shaanxi, China
- Mine Emergency Rescue Innovation Team, The Youth Innovation Team of Shaanxi Universities, Shaanxi, China
| | - Bobo Song
- School of Safety Science and Engineering, Xi'an University of Science and Technology, 58, Yanta Mid. Rd, Xi'an, 710054, Shaanxi, China
- Key Laboratory of Coal Fire Disaster Prevention and Control in Shaanxi Province, Xi'an, 710054, Shaanxi, China
- Mine Emergency Rescue Innovation Team, The Youth Innovation Team of Shaanxi Universities, Shaanxi, China
| | - Wenjun Pan
- School of Safety Science and Engineering, Xi'an University of Science and Technology, 58, Yanta Mid. Rd, Xi'an, 710054, Shaanxi, China
- Key Laboratory of Coal Fire Disaster Prevention and Control in Shaanxi Province, Xi'an, 710054, Shaanxi, China
- Mine Emergency Rescue Innovation Team, The Youth Innovation Team of Shaanxi Universities, Shaanxi, China
| | - Jiuge Wang
- School of Safety Science and Engineering, Xi'an University of Science and Technology, 58, Yanta Mid. Rd, Xi'an, 710054, Shaanxi, China
- Key Laboratory of Coal Fire Disaster Prevention and Control in Shaanxi Province, Xi'an, 710054, Shaanxi, China
- Mine Emergency Rescue Innovation Team, The Youth Innovation Team of Shaanxi Universities, Shaanxi, China
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50
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Chen Y, Ni L, Liu Q, Deng Z, Ding J, Zhang L, Zhang C, Ma Z, Zhang D. Photo-aging promotes the inhibitory effect of polystyrene microplastics on microbial reductive dechlorination of a polychlorinated biphenyl mixture (Aroclor 1260). J Hazard Mater 2023; 452:131350. [PMID: 37030223 DOI: 10.1016/j.jhazmat.2023.131350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/16/2023] [Accepted: 04/01/2023] [Indexed: 05/03/2023]
Abstract
Polychlorinated biphenyls (PCBs) and microplastics (MPs) commonly co-exist in various environments. MPs inevitably start aging once they enter environment. In this study, the effect of photo-aged polystyrene MPs on microbial PCB dechlorination was investigated. After a UV aging treatment, the proportion of oxygen-containing groups in MPs increased. Photo-aging promoted the inhibitory effect of MPs on microbial reductive dechlorination of PCBs, mainly attributed to the inhibition of meta-chlorine removal. The inhibitory effects on hydrogenase and adenosine triphosphatase activity by MPs increased with increasing aging degree, which may be attributed to electron transfer chain inhibition. PERMANOVA showed significant differences in microbial community structure between culturing systems with and without MPs (p < 0.05). Co-occurrence network showed a simpler structure and higher proportion of negative correlation in the presence of MPs, especially for biofilms, resulting in increased potential for competition among bacteria. MP addition altered microbial community diversity, structure, interactions, and assembly processes, which was more deterministic in biofilms than in suspension cultures, especially regarding the bins of Dehalococcoides. This study sheds light on the microbial reductive dechlorination metabolisms and mechanisms where PCBs and MPs co-exist and provides theoretical guidance for in situ application of PCB bioremediation technology.
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Affiliation(s)
- Youhua Chen
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Lingfang Ni
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Qing Liu
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Zhaochao Deng
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Jiawei Ding
- Key Laboratory of Ocean Space Resource Management Technology, MNR, Hangzhou 310012, PR China
| | - Li Zhang
- Guangxi Key Laboratory of Beibu Gulf Marine Resources, Environment and Sustainable Development, Fourth Institute of Oceanography, MNR, Beihai 536000, PR China
| | - Chunfang Zhang
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Zhongjun Ma
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China
| | - Dongdong Zhang
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan 316021, PR China.
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