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Li Z, Yang D, Li S, Yang L, Yan W, Xu H. Advances on electrochemical disinfection research: Mechanisms, influencing factors and applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169043. [PMID: 38070567 DOI: 10.1016/j.scitotenv.2023.169043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/26/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023]
Abstract
Disinfection, a vital barrier against pathogenic microorganisms, is crucial in halting the spread of waterborne diseases. Electrochemical methods have been extensively researched and implemented for the inactivation of pathogenic microorganisms from water and wastewater, primarily owing to their simplicity, efficiency, and eco-friendliness. This review succinctly outlined the core mechanisms of electrochemical disinfection (ED) and systematically examined the factors influencing its efficacy, including anode materials, system conditions, and target species. Additionally, the practical application of ED in water and wastewater treatment was comprehensively reviewed. Case studies involving various scenarios such as drinking water, hospital wastewater, black water, rainwater, and ballast water provided concrete instances of the expansive utility of ED. Finally, coupling ED with other technologies and the resulting synergies were introduced as pivotal foundations for subsequent engineering advancements.
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Affiliation(s)
- Zhen Li
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Duowen Yang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Shanshan Li
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Liu Yang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Wei Yan
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China; Research Institute of Xi'an Jiaotong University, Zhejiang, Hangzhou 311200, China
| | - Hao Xu
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China; Research Institute of Xi'an Jiaotong University, Zhejiang, Hangzhou 311200, China.
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2
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Li D, Guo W, Zhai Y, Xu X, Cao X, Zhao L. The aggregated biofilm dominated by Delftia tsuruhatensis enhances the removal efficiency of 2,4-dichlorophenol in a bioelectrochemical system. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 337:122576. [PMID: 37722473 DOI: 10.1016/j.envpol.2023.122576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/03/2023] [Accepted: 09/16/2023] [Indexed: 09/20/2023]
Abstract
Bioelectrochemical system is a prospective strategy in organic-contaminated groundwater treatment, while few studies clearly distinguish the mechanisms of adsorption or biodegradation in this process, especially when dense biofilm is formed. This study employed a single chamber microbial electrolysis cell (MEC) with two three-dimensional electrodes for removing a typical organic contaminant, 2,4-dichlorophenol (DCP) from groundwater, which inoculated with anaerobic bacteria derived from sewage treatment plant. Compared with the single biodegradation system without electrodes, the three-dimensional electrodes with a high surface enabled an increase of alpha diversity of the microbial community (increased by 52.6% in Shannon index), and provided adaptive ecological niche for more bacteria. The application of weak voltage (0.6 V) furtherly optimized the microbial community structure, and promoted the aggregation of microorganisms with the formation of dense biofilm. Desorption experiment proved that the contaminants were removed from the groundwater mainly via adsorption by the biofilm rather than biodegradation, and compared with the reactor without electricity, the bioelectrochemical system increased the adsorption capacity from 50.0% to 74.5%. The aggregated bacteria on the surface of electrodes were mainly dominated by Delftia tsuruhatensis (85.0%), which could secrete extracellular polymers and has a high adsorption capacity (0.30 mg/g electrode material) for the contaminants. We found that a bioelectrochemical system with a three-dimensional electrode could stimulate the formation of dense biofilm and remove the organic contaminants as well as their possible more toxic degradation intermediates via adsorption. This study provides important guidance for applying bioelectrochemical system in groundwater or wastewater treatment.
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Affiliation(s)
- Deping Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Wenbo Guo
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Ying Zhai
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China; China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, 201306, China
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China; China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, 201306, China.
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Zhang J, Cheng L, Huang L, Ng PH, Huang Q, Marques AR, MacKinnon B, Huang L, Yang Y, Ye R, Sophie SH. In situ generation of highly localized chlorine by laser-induced graphene electrodes during electrochemical disinfection. CHEMOSPHERE 2023:139123. [PMID: 37285986 DOI: 10.1016/j.chemosphere.2023.139123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/09/2023]
Abstract
Laser-induced graphene (LIG) has gained popularity for electrochemical water disinfection due to its efficient antimicrobial activity when activated with low voltages. However, the antimicrobial mechanism of LIG electrodes is not yet fully understood. This study demonstrated an array of mechanisms working synergistically to inactivate bacteria during electrochemical treatment using LIG electrodes, including the generation of oxidants, changes in pH-specifically high alkalinity associated with the cathode, and electro-adsorption on the electrodes. All these mechanisms may contribute to the disinfection process when bacteria are close to the surface of the electrodes where inactivation was independent of the reactive chlorine species (RCS); however, RCS was likely responsible for the predominant cause of antibacterial effects in the bulk solution (i.e., ≥100 mL in our study). Furthermore, the concentration and diffusion kinetics of RCS in solution was voltage-dependent. At 6 V, RCS achieved a high concentration in water, while at 3 V, RCS was highly localized on the LIG surface but not measurable in water. Despite this, the LIG electrodes activated by 3 V achieved a 5.5-log reduction in Escherichia coli (E.coli) after 120-min electrolysis without detectable chlorine, chlorate, or perchlorate in the water, suggesting a promising system for efficient, energy-saving, and safe electro-disinfection.
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Affiliation(s)
- Ju Zhang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Le Cheng
- Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Liqing Huang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Pok Him Ng
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Qianjun Huang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Ana Rita Marques
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Brett MacKinnon
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Libei Huang
- Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Yefeng Yang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - Ruquan Ye
- Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong SAR PR China, China.
| | - St-Hilaire Sophie
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR PR China, China.
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4
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Wei R, Tong H, Zhang J, Sun B, You S. Flow electrochemical inactivation of waterborne bacterial endospores. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130505. [PMID: 36463735 DOI: 10.1016/j.jhazmat.2022.130505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/21/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
Waterborne pathogens have the risk of spreading waterborne diseases and even pandemics. Some Gram-positive bacteria can form endospores, the hardiest known life form that can withstand heat, radiation, and chemicals. Electrochemical inactivation may offer a promising solution, but is hindered by low inactivation efficiencies resulting from limitation of electrode/endospores interaction in terms of electrochemical reaction selectivity and mass transfer. Herein, these issues were addressed through modifying selectivity of active species formation using electroactive ceramic membrane with high oxygen evolution potential, improving mass transfer property by flow-through operation. In this way, inactivation (6.0-log) of Bacillus atrophaeus endospores was achieved. Theoretical and experimental results demonstrated synergistic inactivation to occur through fragmentation of coat via interfacial electron transfer and electro-produced transient radicals (•OH primarily, •Cl and Cl2•- secondarily), thereby increasing cell permeability to facilitate penetration of electro-produced persistent active chlorine for subsequent rupture of intracellular structures. Numbering-up electrode module strategy was proposed to scale up the system, achieving average 5.3-log inactivation of pathogenic Bacillus anthracis endospores for 30 days. This study demonstrates a proof-of-concept manner for effective inactivation of waterborne bacterial endospores, which may provide an appealing strategy for wide-range applications like water disinfection, bio-safety control and defense against biological warfare.
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Affiliation(s)
- Rui Wei
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Hailong Tong
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, PR China
| | - Jinna Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Baiming Sun
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, PR China
| | - Shijie You
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
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5
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Comprehensive study on the role of reactive oxygen species and active chlorine species on the inactivation and subcellular damage of E.coli in electrochemical disinfection. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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6
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Zhao Y, Shao L, Jia L, Meng Z, Liu Y, Wang Y, Zou B, Dai R, Li X, Jia F. Subcellular inactivation mechanisms of Pseudomonas aeruginosa treated by cold atmospheric plasma and application on chicken breasts. Food Res Int 2022; 160:111720. [DOI: 10.1016/j.foodres.2022.111720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/12/2022] [Accepted: 07/19/2022] [Indexed: 11/24/2022]
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7
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Lanrewaju AA, Enitan-Folami AM, Sabiu S, Swalaha FM. A review on disinfection methods for inactivation of waterborne viruses. Front Microbiol 2022; 13:991856. [PMID: 36212890 PMCID: PMC9539188 DOI: 10.3389/fmicb.2022.991856] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Water contamination is a global health problem, and the need for safe water is ever-growing due to the public health implications of unsafe water. Contaminated water could contain pathogenic bacteria, protozoa, and viruses that are implicated in several debilitating human diseases. The prevalence and survival of waterborne viruses differ from bacteria and other waterborne microorganisms. In addition, viruses are responsible for more severe waterborne diseases such as gastroenteritis, myocarditis, and encephalitis among others, hence the need for dedicated attention to viral inactivation. Disinfection is vital to water treatment because it removes pathogens, including viruses. The commonly used methods and techniques of disinfection for viral inactivation in water comprise physical disinfection such as membrane filtration, ultraviolet (UV) irradiation, and conventional chemical processes such as chlorine, monochloramine, chlorine dioxide, and ozone among others. However, the production of disinfection by-products (DBPs) that accompanies chemical methods of disinfection is an issue of great concern due to the increase in the risks of harm to humans, for example, the development of cancer of the bladder and adverse reproductive outcomes. Therefore, this review examines the conventional disinfection approaches alongside emerging disinfection technologies, such as photocatalytic disinfection, cavitation, and electrochemical disinfection. Moreover, the merits, limitations, and log reduction values (LRVs) of the different disinfection methods discussed were compared concerning virus removal efficiency. Future research needs to merge single disinfection techniques into one to achieve improved viral disinfection, and the development of medicinal plant-based materials as disinfectants due to their antimicrobial and safety benefits to avoid toxicity is also highlighted.
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Wilk BK, Szopińska M, Sobaszek M, Pierpaoli M, Błaszczyk A, Luczkiewicz A, Fudala-Ksiazek S. Electrochemical oxidation of landfill leachate using boron-doped diamond anodes: pollution degradation rate, energy efficiency and toxicity assessment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:65625-65641. [PMID: 35501433 DOI: 10.1007/s11356-022-19915-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Electrochemical oxidation (EO), due to high efficiency and small carbon footprint, is regarded as an attractive option for on-site treatment of highly contaminated wastewater. This work shows the effectiveness of EO using three boron-doped diamond electrodes (BDDs) in sustainable management of landfill leachate (LL). The effect of the applied current density (25-100 mA cm-2) and boron doping concentration (B/C ratio: 500 ppm, 10,000 ppm and 15,000 ppm) on the performance of EO was investigated. It was found that, of the electrodes used, the one most effective at COD, BOD20 and ammonia removal (97.1%, 98.8% and 62%, respectively) was the electrode with the lowest boron doping. Then, to better elucidate the ecological role of LLs, before and after EO, cultivation of faecal bacteria and microscopic analysis of total (prokaryotic) cell number, together with ecotoxicity assay (Daphnia magna, Thamnocephalus platyurus and Artemia salina) were combined for the two better-performing electrodes. The EO process was very effective at bacterial cell inactivation using each of the two anodes, even within 2 h of contact time. In a complex matrix of LLs, this is probably a combined effect of electrogenerated oxidants (hydroxyl radicals, active chlorine and sulphate radicals), which may penetrate into the bacterial cells and/or react with cellular components. The toxicity of EO-treated LLs proved to be lower than that of raw ones. Since toxicity drops with increased boron doping, it is believed that appropriate electrolysis parameters can diminish the toxicity effect without compromising the nutrient-removal and disinfection capability, although salinity of LLs and related multistep-oxidation pathways needs to be further elucidated.
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Affiliation(s)
- Barbara Krystyna Wilk
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland.
| | - Malgorzata Szopińska
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland
| | - Michał Sobaszek
- Faculty of Electronics, Telecommunication and Informatics, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland
| | - Mattia Pierpaoli
- Faculty of Electronics, Telecommunication and Informatics, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland
| | - Agata Błaszczyk
- Faculty of Oceanography and Geography, University of Gdansk, Al. Marszałka Piłsudskiego 46, 81-378, Gdynia, Poland
| | - Aneta Luczkiewicz
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland
| | - Sylwia Fudala-Ksiazek
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, 11/12 Narutowicza St, 80-233, Gdansk, Poland
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Rathinavelu S, Divyapriya G, Joseph A, Nambi IM, Muthukrishnan AB, Jayaraman G. Inactivation behavior and intracellular changes in Escherichia coli during electro-oxidation process using Ti/Sb-SnO 2/PbO 2 anode: Elucidation of the disinfection mechanism. ENVIRONMENTAL RESEARCH 2022; 210:112749. [PMID: 35123966 DOI: 10.1016/j.envres.2022.112749] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 12/15/2021] [Accepted: 01/14/2022] [Indexed: 06/14/2023]
Abstract
This study investigates the behavior and intracellular changes in Escherichia coli (model organism) during electro-oxidation with Ti/Sb-SnO2/PbO2 anode in a chlorine free electrochemical system. Preliminary studies were conducted to understand the effect of initial E. coli concentration and applied current density on disinfection. At an applied current density 30 mA cm-2, 7 log reduction of E. coli was achieved in 75 min. The role of reactive oxygen species' (ROS) in E.coli disinfection was evaluated, which confirmed hydroxyl (•OH) radical as the predominant ROS in electro-oxidation. Observations were carried out at cell and molecular level to understand E.coli inactivation mechanism. Scanning electron microscopy images confirmed oxidative damage of the cell wall and irreversible cell death. Intracellular and extracellular protein quantification and genetic material release further confirmed cell component leakage due to cell wall rupture and degradation due to •OH radical interaction. Change in cell membrane potential suggests the colloidal nature of E. coli cells under applied current density. Plasmid deoxyribonucleic acid degradation study confirmed fragmentation and degradation of released genetic material. Overall, effective disinfection could be achieved by electro-oxidation, which ensures effective inactivation and prevents regrowth of E. coli. Disinfection of real wastewater was achieved in 12 min at an applied current density 30 mA cm-2. Real wastewater study further confirmed that effective disinfection is possible with a low cost electrode material such as Ti/Sb-SnO2/PbO2. Energy consumed during disinfection was determined to be 4.978 kWh m-3 for real wastewater disinfection at applied current density 30 mA cm-2. Cost of operation was estimated and stability of the electrode was studied to evaluate the feasibility of large scale operation. Relatively low energy and less disinfection time makes this technology suitable for field scale applications.
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Affiliation(s)
- Sasikaladevi Rathinavelu
- Environmental and Water Resources Division, Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India; Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
| | - Govindaraj Divyapriya
- Environmental and Water Resources Division, Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
| | - Angel Joseph
- Environmental and Water Resources Division, Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
| | - Indumathi M Nambi
- Environmental and Water Resources Division, Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India.
| | - Anantha Barathi Muthukrishnan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
| | - Guhan Jayaraman
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, Tamil Nadu, 600 036, India
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Long Y, Li H, Jin H, Ni J. Electrochemical elimination of Microcystis aeruginosa with boron-doped diamond anode in different electrolyte systems: chemical and biological mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:27677-27687. [PMID: 34984609 DOI: 10.1007/s11356-021-18254-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
The chemical and biological mechanisms of electrochemical elimination of Microcystis aeruginosa (M. aeruginosa) using boron-doped diamond (BDD) anode were comparatively explored in three different electrolytes (chloride, sulfate, and phosphate solutions). The most efficient elimination of M. aeruginosa was observed in chloride solution, which was attributed to the greatest total long-lived oxidants from the favorable formation of active chlorine. Moreover, the high permeability of active chlorine resulted in profound intracellular damages to chlorophyll-a, microcystin-LR (MC-LR), superoxide dismutase (SOD) enzyme, and DNA in the chloride system. The change of membrane permeability and degradation of the released MC-LR induced by active chlorine were further confirmed by the increase of extracellular MC-LR in the initial 5 min and a complete decay in the subsequent 15 min, while the change in morphology of algae cells was insignificant from SEM images. In sulfate and phosphate electrolytes, membrane damages were much more pronounced based on lipid peroxidation observation, although changes in cell morphology was found more significant in phosphate system. The higher concentrations of oxidants (·OH, O3, H2O2, S2O82-) generated in sulfate than in phosphate solution explained the greater efficiency of electrochemical elimination of M. aeruginosa in the sulfate electrolyte in terms of changes of cell density, OD680, chlorophyll-a, MC-LR, lipids, SOD enzyme, and DNA.
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Affiliation(s)
- Yujiao Long
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, 100871, People's Republic of China
| | - Hongna Li
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Hongmei Jin
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China
| | - Jinren Ni
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing, 100871, People's Republic of China.
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11
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Herraiz-Carboné M, Cotillas S, Lacasa E, Vasileva M, Sainz de Baranda C, Riquelme E, Cañizares P, Sáez C. Disinfection of polymicrobial urines by electrochemical oxidation: Removal of antibiotic-resistant bacteria and genes. JOURNAL OF HAZARDOUS MATERIALS 2022; 426:128028. [PMID: 34923384 DOI: 10.1016/j.jhazmat.2021.128028] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
In this work, data obtained from the University Hospital Complex of Albacete (Spain) were selected as a case study to carry out the disinfection experiments. To do this, different configurations of electrochemical reactors were tested for the disinfection of complex urines. Results showed that 4-6 logs bacterial removal were achieved for every bacterium tested when working with a microfluidic flow-through reactor after 180 min (0.423 Ah dm-3). The MIKROZON® cell reached a total disinfection after 60 min (1.212 Ah dm-3), causing severe damages induced in the cell walls observed in SEM images. The concentration profiles of the electrogenerated disinfectants in solution could explain the differences observed. Additionally, a mean decrease in the ARGs concentration ranked as follows: blaKPC (4.18-logs) > blaTEM (3.96-logs) > ermB (3.23-logs) using the MIKROZON® cell. This electro-ozonizer could be considered as a suitable alternative to reduce the risk of antibiotic resistance spread. Hence, this study provides an insight into different electrochemical reactors for the disinfection of complex hospital urine matrices and contributes to reduce the spread of antibiotic resistance through the elimination of ARGs. A topic of great importance nowadays that needs to be further studied.
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Affiliation(s)
- Miguel Herraiz-Carboné
- Department of Chemical Engineering, Higher Technical School of Industrial Engineering, University of Castilla-La Mancha, Edificio Infante Don Juan Manuel, Campus Universitario s/n, 02071 Albacete, Spain
| | - Salvador Cotillas
- Department of Chemical Engineering and Materials, Faculty of Chemical Sciences, Complutense University of Madrid, Avenida Complutense s/n, 28040 Madrid, Spain.
| | - Engracia Lacasa
- Department of Chemical Engineering, Higher Technical School of Industrial Engineering, University of Castilla-La Mancha, Edificio Infante Don Juan Manuel, Campus Universitario s/n, 02071 Albacete, Spain.
| | - Marina Vasileva
- Department of Chemical Engineering, Higher Technical School of Industrial Engineering, University of Castilla-La Mancha, Edificio Infante Don Juan Manuel, Campus Universitario s/n, 02071 Albacete, Spain
| | - Caridad Sainz de Baranda
- Clinical Parasitology and Microbiology Area, University Hospital Complex of Albacete, C/Hermanos Falcó 37, 02006 Albacete, Spain
| | - Eva Riquelme
- Clinical Parasitology and Microbiology Area, University Hospital Complex of Albacete, C/Hermanos Falcó 37, 02006 Albacete, Spain
| | - Pablo Cañizares
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
| | - Cristina Sáez
- Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, Edificio Enrique Costa Novella, Campus Universitario s/n, 13005 Ciudad Real, Spain
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12
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Budil J, Szabó O, Lišková P, Štenclová P, Izsák T, Potocký Š, Kromka A. Impact of electrolyte solution on electrochemical oxidation treatment of Escherichia coli K-12 by boron-doped diamond electrodes. Lett Appl Microbiol 2022; 74:924-931. [PMID: 35239229 DOI: 10.1111/lam.13687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/27/2022] [Accepted: 02/25/2022] [Indexed: 11/29/2022]
Abstract
We studied the disinfection efficacy of boron-doped electrodes on Escherichia coli-contaminated water-based solutions in three different electrolytes, physiological solution (NaCl), phosphate buffer (PB), and phosphate buffer saline (PBS). The effect of the electrochemical oxidation treatment on the bacteria viability was studied by drop and spread plate cultivation methods, and supported by optical density measurements. We have found that bacterial suspensions in NaCl and PBS underwent a total inactivation of all viable bacteria within 10 min of the electrochemical treatment. By contrast, experiments performed in the PB showed a relatively minor decrease of viability by two orders of magnitude after two hours of the treatment, which is almost comparable with the untreated control. The enhanced bacterial inactivation was assigned to reactive chlorine species (RCS), capable of penetrating the bacterial cytoplasmic membrane and killing bacteria from within.
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Affiliation(s)
- Jakub Budil
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic.,Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 43 Prague 2, Czech Republic
| | - Ondrej Szabó
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic
| | - Petra Lišková
- Department of Genetics and Microbiology, Faculty of Science, Charles University, Viničná 5, 128 43 Prague 2, Czech Republic
| | - Pavla Štenclová
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic
| | - Tibor Izsák
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic.,Institute of Electrical Engineering, Slovak Academy of Sciences, Dúbravská cesta 9, 841 04, Bratislava, Slovakia
| | - Štěpán Potocký
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic
| | - Alexander Kromka
- Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10, 162 00, Prague 6, Czech Republic
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Dang C, Wan J, Zhang Y, Li Z, Fu J. Effect of Nano-Silver on Formation of Marine Snow and the Underlying Microbial Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:995-1006. [PMID: 34978429 DOI: 10.1021/acs.est.1c06494] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Roller experiments were conducted to explore the effect of nano-silver on the formation of marine snow and the underlying microbial mechanism. With the increasing concentration of nano-Ag from 1 ng/L to 1 mg/L, the formation and aggregation of marine snow particles were solidly suppressed in a dose-dependent pattern. Moreover, the formed marine snows tended to be thinner fibrous particles with smaller size and increased edge smoothness and compactness in the presence of nano-Ag. The microbial analyses indicated that nano-Ag not only inhibited the development of biomass but also changed the species composition and functional profile of the microbial community. Nano-Ag obviously inhibited most of the abundant species, except for some myxobacteria, which is unfavorable for the microbial community stability. For the microbial functions, some major biological processes including the growth, metabolic, and cellular processes were also inhibited by the high dosage of nano-Ag. The strong microbial inhibition of nano-Ag would contribute to the suppression on the formation of marine snow. Specifically, the function genes of extracellular polymeric substance synthesis and secretion were significantly reduced by nano-Ag, which might be the key and straight microbial factor in suppressing the formation of marine snow.
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Affiliation(s)
- Chenyuan Dang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jing Wan
- 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
| | - Zhang Li
- 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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14
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Liu Y, Zhang S, Fang H, Wang Q, Jiang S, Zhang C, Qiu P. Inactivation of antibiotic resistant bacterium Escherichia coli by electrochemical disinfection on molybdenum carbide electrode. CHEMOSPHERE 2022; 287:132398. [PMID: 34597647 DOI: 10.1016/j.chemosphere.2021.132398] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
Antibiotic-resistant bacteria (ARB) pose a substantial threat to public health worldwide. Electrochemistry, as a low energy consumption and environmentally friendly technique, is ideal for inactivating ARB. This study explored the utility of electrochemical disinfection (ED) for inactivating ARB (Escherichia coli K-12 LE392 resistant to kanamycin, tetracycline, and ampicillin) and the regrowth potential of the treated ARB. The results revealed that 5.12-log ARB removal was achieved within 30 min of applying molybdenum carbide as the anode and cathode material under a voltage of 2.0 V. No ARB regrowth was observed in the cathode chamber after 60 min of incubation in unselective broth, demonstrating that the process in the cathode chamber was more effective for permanent inactivation of ARB. The mechanisms underlying the ARB inactivation were verified based on intercellular reactive oxygen species (ROS) measurement, membrane integrity detection, and genetic damage assessment. Higher ROS production and membrane permeability were observed in the cathode and anode groups (p < 0.001) compared to the control group (0 V). In addition, the DNA was more likely to be damaged during the ED process. Collectively, our results demonstrate that ED is a promising technology for disinfecting water to prevent the spread of ARB.
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Affiliation(s)
- Yinghan Liu
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Shuai Zhang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - Hao Fang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Shan Jiang
- South China Institute of Environmental Science, MEE, China
| | - Chenxi Zhang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Pengxiang Qiu
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), Nanjing University of Information Science & Technology, Nanjing, 210044, China
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15
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Long Y, Li H, Jin H, Ni J. Interpretation of high perchlorate generated during electrochemical disinfection in presence of chloride at BDD anodes. CHEMOSPHERE 2021; 284:131418. [PMID: 34323797 DOI: 10.1016/j.chemosphere.2021.131418] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/31/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Perchlorate is a disinfection by-product (DBP) of serious health concern. Herein, the long sought mechanism of high perchlorate production during electrochemical disinfection at boron-doped diamond (BDD) anode in the presence of chloride was elucidated. The generated perchlorate at BDD during electrochemical disinfection (in 10 mM NaCl) in 60 min reached 0.125 mM, which was 830 times higher than the EPA standard. In contrast, perchlorate at PbO2 and SnO2 anodes was below the detection limit. Further experiments employing NaClO3 revealed that the conversion ratio from ClO3- to ClO4- in 10 h at BDD (98%) was considerably higher than PbO2 (13%) and SnO2 (12%). Such significant difference among anodes was fully interpreted with a two-step mechanism. The first step is essential to produce ·ClO3 by oxidizing ClO3- at electrodes. Otherwise, the conversion to perchlorate would be impossible even with excessive ·OH, which was verified with the photocatalysis process. The second step is the perchlorate generation with radical reaction between ·ClO3 and ·OH, where the primary role of ·OH was substantiated by scavenging test. Interestingly, the capability of perchlorate production was correlated with free ·OH instead of the total amount of ·OH. Despite the similar abilities of electron transfer between anodes and ClO3-, much higher free ·OH exists at BDD anode than at PbO2 and SnO2 anodes through chronoamperometry experiments and work function characterization, which reasonably provides interpretation of high perchlorate production at BDD anode.
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Affiliation(s)
- Yujiao Long
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China
| | - Hongna Li
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Hongmei Jin
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Jinren Ni
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
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Inactivation of pathogens by visible light photocatalysis with nitrogen-doped TiO2 and tourmaline-nitrogen co-doped TiO2. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118979] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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17
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The Pathway towards Photoelectrocatalytic Water Disinfection: Review and Prospects of a Powerful Sustainable Tool. Catalysts 2021. [DOI: 10.3390/catal11080921] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Photoelectrocatalysis is a hybrid photon/electron-driven process that benefits from the synergistic effects of both processes to enhance and stabilize the generation of disinfecting oxidants. Photoelectrocatalysis is an easy to operate technology that can be scaled-up or scaled-down for various water treatment applications as low-cost decentralized systems. This review article describes the fundamentals of photoelectrocatalysis, applied to water disinfection to ensure access to clean water for all as a sustainable development goal. Advances in reactor engineering design that integrate light-delivery and electrochemical system requirements are presented, with a description of photo-electrode material advances, including doping, nano-decoration, and nanostructure control. Disinfection and cell inactivation are described using different model microorganisms such as E. coli, Mycobacteria, Legionella, etc., as well the fungus Candida parapsilosis, with relevant figures of merit. The key advances in the elucidation of bacterial inactivation mechanisms by photoelectrocatalytic treatments are presented and knowledge gaps identified. Finally, prospects and further research needs are outlined, to define the pathway towards the future of photoelectrocatalytic disinfection technologies.
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19
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Chen YD, Duan X, Zhou X, Wang R, Wang S, Ren NQ, Ho SH. Advanced oxidation processes for water disinfection: Features, mechanisms and prospects. CHEMICAL ENGINEERING JOURNAL 2021. [PMID: 0 DOI: 10.1016/j.cej.2020.128207] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
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Xu H, Zhu Y, Du M, Wang Y, Ju S, Ma R, Jiao Z. Subcellular mechanism of microbial inactivation during water disinfection by cold atmospheric-pressure plasma. WATER RESEARCH 2021; 188:116513. [PMID: 33091801 DOI: 10.1016/j.watres.2020.116513] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/15/2020] [Accepted: 10/10/2020] [Indexed: 06/11/2023]
Abstract
Although the identification of effective reactive oxygen species (ROS) generated by plasma has been extensively studied, yet the subcellular mechanism of microbial inactivation has never been clearly elucidated in plasma disinfection processes. In this study, subcellular mechanism of yeast cell inactivation during plasma-liquid interaction was revealed in terms of comprehensive factors including cell morphology, membrane permeability, lipid peroxidation, membrane potential, intracellular redox homeostasis (intracellular ROS and H2O2, and antioxidant system (SOD, CAT and GSH)), intracellular ionic equilibrium (intracellular H+ and K+) and energy metabolism (mitochondrial membrane potential, intracellular Ca2+ and ATP level). The ROS analysis show that ·OH, 1O2, ·O2-and H2O2 were generated in this plasma-liquid interaction system and ·O2-served as the precursor of 1O2. Additionally, the solution pH was reduced. Plasma can effectively inactivate yeast cells mainly via apoptosis by damaging cell membrane, intracellular redox and ion homeostasis and energy metabolism as well as causing DNA fragmentation. ROS scavengers (l-His, d-Man and SOD) and pH buffer (phosphate buffer solution, PBS) were employed to investigate the role of five antimicrobial factors (·OH, 1O2, ·O2-, H2O2 and low pH) in plasma sterilization. Results show that they have different influences on the aforementioned cell physiological activities. The ·OH and 1O2 contributed most to the yeast inactivation. The ·OH mainly attacked cell membrane and increased cell membrane permeability. The disturb of cell energy metabolism was mainly attributed to 1O2. The damage of cell membrane as well as extracellular low pH could break the intracellular ionic equilibrium and further reduce cell membrane potential. The remarkable increase of intracellular H2O2 was mainly due to the influx of extracellular H2O2 via destroyed cell membrane, which played a little role in yeast inactivation during 10-min plasma treatment. These findings provide comprehensive insights into the antimicrobial mechanism of plasma, which can promote the development of plasma as an alternative water disinfection strategy.
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Affiliation(s)
- Hangbo Xu
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yupan Zhu
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Mengru Du
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yuqi Wang
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Siyao Ju
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Ruonan Ma
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China.
| | - Zhen Jiao
- Henan Key Laboratory of Ion-beam Bioengineering, College of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China.
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Mohan H, Ramalingam V, Lim JM, Lee SW, Kim J, Lee JH, Park YJ, Seralathan KK, Oh BT. E-waste based graphene oxide/V2O5/Pt ternary composite: Enhanced visible light driven photocatalyst for anti-microbial and anti-cancer activity. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125469] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Zhan Y, Hong N, Yang B, Du Y, Wu Q, Liu A. Toxicity variability of urban road stormwater during storage processes in Shenzhen, China: Identification of primary toxicity contributors and implications for reuse safety. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 745:140964. [PMID: 32717603 DOI: 10.1016/j.scitotenv.2020.140964] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/09/2020] [Accepted: 07/12/2020] [Indexed: 05/18/2023]
Abstract
Urban road stormwater reuse is one of the most important ways to mitigate water resource shortage. Generally, stormwater is stored prior to reuse or further treatment. This study explored the stormwater toxicity variability during two types of storages, closed and open storages using Chinese hamster ovary cells (CHO), which are mammalian cells. The toxicity test by CHO cells can indirectly represent the risk related to human health. Both rainfall (without reaching ground surfaces) and urban road stormwater were collected to undertake laboratory-scaled storage experiments and basic water quality parameters (pH and dissolved oxygen), microorganisms (E.coli and total bacteria), total organic carbon and heavy metals (copper, Cu, zinc, Zn, nickel, Ni, chromium, Cr, cadmium, Cd and lead, Pb) were also investigated during storage processes. The outcomes showed that rainfall has a better water quality with lower toxicity than urban road stormwater (EC50 values of rainfall were generally twice higher than road stormwater). Additionally, it is found that storing road stormwater for a certain period would reduce the toxicity and hence improve their reuse safety (EC50 values in Day 1 were 10.30 mL and 8.46 mL for closed and open storage respectively while they were 14.3 mL and 13.0 mL in Day 7). Organic matters and Cu are important contributors of toxicity during both closed and open storages while bacteria is also essential in toxicity contribution in open storage. The research results implied that storing stormwater for a certain period has a benefit for reuse safety. This is related to cost-effectiveness in terms of treatment system design to avoid over engineering. Additionally, it is suggested that for reducing toxicity, the stormwater treatment designed before/after storage devices should focus on removal of organic matters and heavy metals (specially Cu) as well as restraining bacteria growth.
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Affiliation(s)
- Yuting Zhan
- College of Chemistry and Environmental Engineering, Shenzhen University, 518060 Shenzhen, China
| | - Nian Hong
- College of Chemistry and Environmental Engineering, Shenzhen University, 518060 Shenzhen, China
| | - Bo Yang
- College of Chemistry and Environmental Engineering, Shenzhen University, 518060 Shenzhen, China
| | - Ye Du
- Guangdong Provincial Engineering Technology Research Centre for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, 518055 Shenzhen, China
| | - Qianyuan Wu
- Guangdong Provincial Engineering Technology Research Centre for Urban Water Cycle and Water Environment Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, 518055 Shenzhen, China
| | - An Liu
- College of Chemistry and Environmental Engineering, Shenzhen University, 518060 Shenzhen, China.
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Chen X, Wang Y, Li W, Zhang J, Qi W, Lu Y, Ding Z. Coupling changes of disinfectant and bacteria induced by the water stagnation and disinfection strategy. CHEMOSPHERE 2020; 242:125190. [PMID: 31704528 DOI: 10.1016/j.chemosphere.2019.125190] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/21/2019] [Accepted: 10/21/2019] [Indexed: 06/10/2023]
Abstract
This paper studied stagnation-induced changes of disinfectant and bacteria using an orthogonal test and kinetic analysis, and then proposed a disinfection strategy. Tap water from a drinking water distribution system and ultrafiltrated water were collected and disinfected with four disinfectants (concentrations were set 0.2-1 mg/L as Cl2. The study had several findings. First, disinfectants expanded lag phases and shortened generation times of the microbiome. Reduction in culturability, substrate responsiveness, respiratory activity, membrane potential and integrity subsequently occurred with increasing disinfection concentration. Second, the disinfectant decay rate decreased with initial disinfection concentration, and the effective disinfection phase (heterotrophic plate count (HPC) was less than 100 cfu/mL) was longer in water samples with lower organic matter. Moreover, the disinfection process was divided into an effective phase and an invalid phase (HPC>100 cfu/mL). Then a disinfection efficiency model was built and the regulation of disinfection by-products (DBPs) production was studied in chlorinated water samples, which provides a general method for other disinfectant studies. The average trihalomethanes (THMs) production during the effective phase (marked as THM/th) and THMs production during the invalid phase (marked as ΔTHM) were proposed to evaluate the DBPs production. The level of THM/th and ΔTHM were lower in ultrafiltrated water than those in tap water. THM/th were negatively correlated with initial chlorine concentration while ΔTHM were positively correlated with initial chlorine concentration. Finally, for the purpose of raising disinfection efficiency and decreasing DBPs, we propose periodic pulse disinfection.
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Affiliation(s)
- Xiao Chen
- College of Defense Engineering, The Army Engineering University of PLA, Nanjing, 210007, China
| | - Yi Wang
- College of Defense Engineering, The Army Engineering University of PLA, Nanjing, 210007, China.
| | - Weiying Li
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Junpeng Zhang
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; Shanghai Pudong Veolia Water Supply Co., Ltd., Shanghai, 200120, China
| | - Wanqi Qi
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
| | - Yaofeng Lu
- College of Defense Engineering, The Army Engineering University of PLA, Nanjing, 210007, China
| | - Zhibin Ding
- College of Defense Engineering, The Army Engineering University of PLA, Nanjing, 210007, China.
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Yu P, Zhou X, Li Z, Yan Y. Inactivation and change of tetracycline-resistant Escherichia coli in secondary effluent by visible light-driven photocatalytic process using Ag/AgBr/g-C 3N 4. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135639. [PMID: 31841919 DOI: 10.1016/j.scitotenv.2019.135639] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 11/05/2019] [Accepted: 11/18/2019] [Indexed: 05/27/2023]
Abstract
Control of antibiotic-resistant bacteria (ARB) and their related genes in secondary effluents has become a serious issue because of increased awareness of their health risks. A considerable number of techniques have been developed in recent years, particularly in relation to advanced oxidation. However, limited information is known about cellular behavior and resistance characteristic change during photocatalytic treatment. In this study, the inactivation of tetracycline (TC)-resistant Escherichia coli (TC-E. coli), removal of TC-resistant genes (TC-RGs), and antibiotic susceptibility were evaluated by employing photocatalytic treatment using Ag/AgBr/g-C3N4 with visible light irradiation. The effects of light intensity, photocatalyst dosage, and reaction ambient temperature on photocatalysis were modelled and investigated. The rate of TC-E. coli removal was also optimized. Results demonstrated that the optimal conditions for TC-E. coli removal included light intensity of 96.0 mW/cm2, photocatalyst dosage of 211.0 mg/L, and reaction ambient temperature of 23.7 °C. Under such conditions, the ARB removal rate was 6.1 log after 90 min and the related TC-RG removal rates were 49%, 86%, 69%, and 86% for tetA, tetM, tetQ, and intl1, respectively. The minimum inhibitory concentration test after photocatalysis shows that the antibiotic resistance of TC-E. coli was enhanced, which may be mainly due to the changes in the membrane potential and resulted in difficulty in destroying the bacteria through antibiotic contact. Hence, photocatalytic treatment could be an ideal method for ARB and antibiotic-resistant gene (ARG) control in wastewater, but the health risks of the remaining ARB and ARG should be investigated further.
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Affiliation(s)
- Peng Yu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Zifu Li
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Yichang Yan
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
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25
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Cheng Y, Song R, Wu K, Peng N, Yang M, Luo J, Zou T, Zuo Y, Liu Y. The enhanced visible-light-driven antibacterial performances of PTCDI-PANI(Fe(III)-doped) heterostructure. JOURNAL OF HAZARDOUS MATERIALS 2020; 383:121166. [PMID: 31520932 DOI: 10.1016/j.jhazmat.2019.121166] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 05/25/2023]
Abstract
The development of visible-light-responsive photocatalysts with organic semiconductors is considered as an important and promising way to solve the energy crisis and environmental pollution. In this work, PTCDI and PTCDI-PANI(Fe(III)-doped) heterostructure were prepared through radical polymerization and modified amidation reaction. They could be used as visible-light-driven photocatalysts for the treatment of medical wastewater containing Staphylococcus aureus and E. coli bacteria. The as-prepared PTCDI-PANI(Fe(III)-doped) exhibited comparably higher photocatalytic activity beyond PTCDI. Under the irradiation of visible light, the PTCDI-PANI(Fe(III)-doped) showed optimized sterilization efficiencies towards E. coli and Staphylococcus aureus bacteria, which was 95.8% and 99.3%, respectively. The enhanced photo-induced antibacterial effect by PANI(Fe(III)-doped)-grafting was mainly attributed to: (1) PANI has a narrow band gap of 2.8 eV; (2) The relatively higher conduction band position (-2.1 eV) of PANI promotes the reaction of O2+e-⟶·OH; (3) The strengthened junctions of amide bond between PTCDI and PANI improve the separation efficiency of photogenerated electron-hole pairs; (4) The relatively rougher surface of PTCDI-PANI comparing with PTCDI improves the bio-surface interactions or bacterial adhesion; (5) Fe(III)-doping acts as a conducting tunnel and promotes the charge transfer between PANI and PTCDI.
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Affiliation(s)
- Yang Cheng
- The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, PR China; Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Ruqian Song
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Kui Wu
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Na Peng
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Mian Yang
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Jing Luo
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Tao Zou
- The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan, 430081, PR China; Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China; Key Laboratory of Biomedical Polymers of Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China.
| | - Yuegang Zuo
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, North Dartmouth, MA 02747, USA.
| | - Yi Liu
- Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China; Key Laboratory of Analytical Chemistry for Biology and Medicine (MOE), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, PR China.
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26
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Lei Q, Zheng J, Ma J, Wang X, Wu Z, Wang Z. Simultaneous solid-liquid separation and wastewater disinfection using an electrochemical dynamic membrane filtration system. ENVIRONMENTAL RESEARCH 2020; 180:108861. [PMID: 31703975 DOI: 10.1016/j.envres.2019.108861] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/16/2019] [Accepted: 10/25/2019] [Indexed: 05/15/2023]
Abstract
An electrochemical dynamic membrane filtration (EDMF) system for simultaneous solid-liquid separation (also protecting electrodes against fouling) and sewage disinfection was developed. At a low voltage of 2.5 V, efficient disinfection performance was achieved in the EDMF, with ~100% log removal efficiency (no detectable bacteria in the effluent). Results also demonstrated that the EDMF system, operated at membrane flux of 100 L/(m2 h), could maintain long-lasting bacterial disinfection efficiency of real wastewater (~100% log removal) in continuous flow tests. Transmembrane pressure (TMP) increased from 0.8 kPa to 22 kPa within 80 d (one operation cycle), and cleaning of EDMF could effectively restore TMP and biocidal behaviors for subsequent filtration cycles. In contrast, without dynamic membrane, the disinfection efficiency was decreased from initial ~100% log removal (with no detectable live bacteria) to ~44.4% log removal within 7 d. Reactive oxygen species (ROS)-mediated oxidation was responsible for bacteria disinfection in the EDMF, and HO• and H2O2 generated in this system played a dominant role, causing damage to cell membranes and K+ leakage from cytosol. Moreover, catalase and superoxide dismutase for intracellular ROS attenuation were inhibited, resulting in the increase of intracellular oxidative stress and thus high-efficient disinfection. These results highlight the potential of EDMF system to be used for wastewater treatment and disinfection.
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Affiliation(s)
- Qian Lei
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Junjian Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Jinxing Ma
- UNSW Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Xueye Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Zhichao Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
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Yu P, Zhou X, Yan Y, Li Z, Zheng T. Enhanced visible-light-driven photocatalytic disinfection using AgBr-modified g-C 3N 4 composite and its mechanism. Colloids Surf B Biointerfaces 2019; 179:170-179. [PMID: 30959229 DOI: 10.1016/j.colsurfb.2019.03.074] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 03/08/2019] [Accepted: 03/31/2019] [Indexed: 11/25/2022]
Abstract
In this study, novel AgBr-modified g-C3N4 (AgBr/g-C3N4) photocatalysts were prepared by an adsorption-deposition method and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and ultraviolet-visible spectroscopy (UV-vis). Furthermore, the photocatalytic disinfection performance on Escherichia coli (ATCC 15597) was investigated. The as-prepared photocatalysts exhibited well crystalline structures and morphologies with C3N4 and exhibited a stronger bacterial inactivation than that of pristine g-C3N4. The disinfection efficiency reached up to 4.80 log under 150 min of visible light irradiation when AgBr-modified g-C3N4 was prepared at a molar ratio of 1:5 (AgBr: g-C3N4), which was a 4.2 log increase compared with that of pristine g-C3N4 under the same experimental conditions. The enhancement of the photocatalytic activity of AgBr/g-C3N4 was attributed to the effective production and transfer of the photo-induced electrons under visible light irradiation, since the AgBr modification reduced the bandgap energy and boarded the visible light area. Furthermore, h+ was found to be the dominant contributor for bacterial inactivation. The h+ and photo-generated reactive oxygen species (ROSs) damaged the cell membranes and destroyed metabolic processes, resulting in leakage of potassium ions and proteins, lipid peroxidation, degradation of intracellular protein, and a reduction of the ATP levels, which finally lead to bacterial death. These results provide a theoretical basis for the development of low-cost, high-efficiency photocatalysts for green/sustainable water disinfection.
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Affiliation(s)
- Peng Yu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Yichang Yan
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Zifu Li
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, PR China; Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Tianlong Zheng
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, PR China
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28
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Jin Y, Shi Y, Chen R, Chen X, Zheng X, Liu Y. Electrochemical disinfection using a modified reticulated vitreous carbon cathode for drinking water treatment. CHEMOSPHERE 2019; 215:380-387. [PMID: 30336315 DOI: 10.1016/j.chemosphere.2018.10.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 10/08/2018] [Accepted: 10/10/2018] [Indexed: 06/08/2023]
Abstract
A reticulated vitreous carbon (RVC) cathode modified by anodic polarization in 20 wt% H2SO4 solution was used for drinking water disinfection under a neutral low electrolyte concentration (0.25 g/L Na2SO4) condition. The contribution of the modified RVC anode and the Ti/RuO2 cathode to disinfection was investigated. The influences of current, initial Escherichia coli load, temperature and water volume were studied. The results show that H2O2 generation increased to approximately three times using the modification of the RVC. E. coli was mainly deactivated by the H2O2 generated at the cathode. For water with about 106 CFU/mL E. coli, the detection limit (<4 CFU/mL) was reached under different conditions. Increasing current could simultaneously shorten the treatment time and increase the energy consumption (EC) simultaneously. Although decreasing the initial load reduced the treatment time, the EC for per log E. coli removal increased. The time required for disinfection shortened from 3.5 to 2.5 h and the EC for per log removal decreased from 218.5 to 123.2 Wh/m3 when the temperature increased from 20 to 40 °C. Although more time was required for disinfection, the EC decreased from 218.5 to 141.4 Wh/m3 when the volume was doubled.
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Affiliation(s)
- Yanchao Jin
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China
| | - Yijun Shi
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China
| | - Riyao Chen
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China.
| | - Xiao Chen
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China
| | - Xi Zheng
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China
| | - Yaoxing Liu
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China
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Liang S, Lin H, Habteselassie M, Huang Q. Electrochemical inactivation of bacteria with a titanium sub-oxide reactive membrane. WATER RESEARCH 2018; 145:172-180. [PMID: 30142515 DOI: 10.1016/j.watres.2018.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 08/03/2018] [Accepted: 08/04/2018] [Indexed: 06/08/2023]
Abstract
A reactive electrochemical membrane (REM) system was developed with titanium suboxide microfiltration membrane serving as the filter and the anode, and was examined to inactivate Escherichia coli (E. coli) in water at various current densities. After passing through the membrane filter, the concentration of E. coli decreased from 6.46 log CFU/mL to 0.18 log CFU/mL. The REM operation and effects, including membrane pressure, anode potential, protein leakage, and cell morphology, were characterized under different treatment conditions. It was found that several mechanisms, including membrane filtration, external electrical field influence, and direct oxidation, functioned in concert to lead to bacteria removal and inactivation, and direct oxidation likely played the major role. As revealed by scanning electron microscope and extracellular protein analysis, high current density and voltage caused severe cell damage that resulted in partial or complete cell disintegration. The removal of a model virus, bacteriophage MS2, was also investigated at the current density of 10 mA cm-2 and achieved 6.74 log reduction compared to the original concentration (1011 PFU/mL). In addition to illustration of mechanisms, this study may provide a potentially promising approach that is suitable for decentralized treatment to meet dispersed water disinfection needs.
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Affiliation(s)
- Shangtao Liang
- College of Agricultural and Environmental Sciences, Department of Crop and Soil Sciences, University of Georgia, Griffin, GA, 30223, United States; AECOM Environment, Atlanta, GA, 30309, United States
| | - Hui Lin
- Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan, 523808, PR China.
| | - Mussie Habteselassie
- College of Agricultural and Environmental Sciences, Department of Crop and Soil Sciences, University of Georgia, Griffin, GA, 30223, United States
| | - Qingguo Huang
- College of Agricultural and Environmental Sciences, Department of Crop and Soil Sciences, University of Georgia, Griffin, GA, 30223, United States.
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Kourdali S, Badis A, Boucherit A, Boudjema K, Saiba A. Electrochemical disinfection of bacterial contamination: Effectiveness and modeling study of E. coli inactivation by electro-Fenton, electro-peroxi-coagulation and electrocoagulation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 226:106-119. [PMID: 30114570 DOI: 10.1016/j.jenvman.2018.08.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 08/01/2018] [Accepted: 08/07/2018] [Indexed: 06/08/2023]
Abstract
The present work undertakes an examination and comparison of electro-Fenton (EF), electro-peroxi-coagulation (EPC) and electrocoagulation (EC) applied to the E. coli inactivation in batch reactor. Indeed, platinum (Pt (anode), EF), stainless steel (SS (cathode), EF, EPC) and ordinary steel (Fe (anode), EPC) and aluminum (Al, EC) were used respectively. The current intensity, nature of electrolytic support, bacterial density and hydrogen peroxide (H2O2) concentration are the most influenced study parameters. The obtained results showed that the high current intensities were significant for better inactivation and destruction of E. coli cells and caused a maximum of energy consumption. Both disinfection and energy consumption were improved by adding NaCl (or Na2SO4) in the three processes. Higher cellular density limited the electrochemical process and has negative effect in E. coli inactivation and the energy consumption. Only in the EPC case, the disinfection was considerably increased in function with H2O2 concentration. The modeling parameters of the inactivation kinetics of E. coli showed a good fitting of the established model (0.9560 < R2 < 0.9979, 0.9267 < R2 adjusted <0.997 and 0.0189 < RMSE <0.4821), faster kinetics of E. coli inactivation (significant values of Kmax and Sl) in the case of high current intensity (0.2442<Kmax<0.7440 and 10.50 < Sl < 24.69), the presence of chlorides or sulfates (0.6662<Kmax<0.7818 and 11.67 < Sl < 18.59), and the sufficient H2O2 concentration (0.4712<Kmax<0.9204 and 13.00 < Sl < 16.38). Moreover, the analysis of the results revealed that the EF is more effective in terms of the E. coli inactivation and the energy consumption comparatively to the other studied processes.
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Affiliation(s)
- Sidali Kourdali
- Department of Process Engineering, Faculty of Technology, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria; National Centre for Research and Development of Fisheries and Aquaculture (CNRDPA) 11, Bd Amirouche P.O. Box 67, Bousmail, W. Tipaza, Algeria.
| | - Abdelmalek Badis
- Department of Process Engineering, Faculty of Technology, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria; National Centre for Research and Development of Fisheries and Aquaculture (CNRDPA) 11, Bd Amirouche P.O. Box 67, Bousmail, W. Tipaza, Algeria; Laboratory of Natural Substances Chemistry and Biomolecules, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria
| | - Ahmed Boucherit
- Department of Process Engineering, Faculty of Technology, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria; Laboratory of Chemical Engineering, University Saad Dahlab of Blida 1, P.O.Box 270, 09000, Blida, Algeria
| | - Kamel Boudjema
- Department of Process Engineering, Faculty of Technology, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria; National Centre for Research and Development of Fisheries and Aquaculture (CNRDPA) 11, Bd Amirouche P.O. Box 67, Bousmail, W. Tipaza, Algeria
| | - Ali Saiba
- Department of Process Engineering, Faculty of Technology, University of Saàd Dahlab Blida 1, P.O. Box 270, 09000, Blida, Algeria
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Wu Y, Shi YG, Zeng LY, Pan Y, Huang XY, Bian LQ, Zhu YJ, Zhang RR, Zhang J. Evaluation of antibacterial and anti-biofilm properties of kojic acid against five food-related bacteria and related subcellular mechanisms of bacterial inactivation. FOOD SCI TECHNOL INT 2018; 25:3-15. [DOI: 10.1177/1082013218793075] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Although the antimicrobial properties of kojic acid have been recognized, the subcellular mechanism of bacterial inactivation caused by it has never been clearly elucidated. In the present study, the antibacterial and anti-biofilm activity of kojic acid was evaluated against five foodborne pathogens including Listeria monocytogenes, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Salmonella typhimurium. The antibacterial activity was determined by minimum inhibitory concentration, minimum bactericidal concentration, and the time-kill assay. Among them, the susceptibility of Escherichia coli was significant with the lowest minimum inhibitory concentration and minimum bactericidal concentration values of 10 and 20 mM, respectively. Subcellular mechanism of bacterial inactivation related to kojic acid was revealed through comprehensive factors including cell morphology, membrane permeability, K+ leakage, zeta potential, intracellular enzyme, and DNA assay. Results demonstrated that bacterial inactivation caused by kojic acid, especially for Gram-negative bacteria, was primarily induced by the pronounced damage to the cell membrane integrity. Leakage of intracellular enzyme to the supernatants implied that the cell membrane permeability was compromised. Consequently, the release of K+ from the cytosol leads to the alterations of the zeta potential of cells, which would disturb the subcellular localization of some proteins and thereby cause the bacterial inactivation. The free −CH2OH group at the C-2 of kojic acid could play more significant role in the antimicrobial performance of kojic acid against Gram-negative bacteria. Moreover, remarkable interaction with DNA was also observed. Kojic acid at sub-minimum inhibitory concentration inhibited biofilm formation by these bacteria.
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Affiliation(s)
- Yu Wu
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Yu-gang Shi
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Lu-yao Zeng
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Ying Pan
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Xin-ying Huang
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Li-qing Bian
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Yun-jie Zhu
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Run-run Zhang
- Zhejiang Provincial Collaborative Innovation Center of Food Safety and Nutrition, Zhejiang Gongshang University, Hangzhou, China
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Juan Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China
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Lv Q, Zhang B, Xing X, Zhao Y, Cai R, Wang W, Gu Q. Biosynthesis of copper nanoparticles using Shewanella loihica PV-4 with antibacterial activity: Novel approach and mechanisms investigation. JOURNAL OF HAZARDOUS MATERIALS 2018; 347:141-149. [PMID: 29304452 DOI: 10.1016/j.jhazmat.2017.12.070] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 12/11/2017] [Accepted: 12/28/2017] [Indexed: 05/02/2023]
Abstract
Metallic nanoparticle based disinfection represents a promising approach for microbial pollution control in drinking water and thus, biosynthesis of non precious metal nanoparticles is of considerable interest. Herein, an original and efficient route for directly microbial synthesis of copper nanoparticles (Cu-NPs) by Shewanella loihica PV-4 is described and their satisfactorily antimicrobial activities are established. Cu-NPs were successfully synthesized and most of them attaching on the bacterial cell surfaces suggested extracellular Cu(II) bioreduction mainly contributed to this biosynthesis. Using a suite of characterization methods, polycrystalline nature and face centered cubic lattice of Cu-NPs were revealed, with size in the range of 10-16 nm. With Cu-NPs dosage of 100 μg/mL and 105 CFU/mL fresh Escherichia coli suspension, the obtained antibacterial efficiency reached as high as 86.3 ± 0.2% within 12 h. Cell damages were primarily caused by the generated reactive oxygen species with H2O2 playing significant roles. Both cell membrane and cytoplasm components were destroyed, while the key inactivation mechanisms were lipid peroxidation and DNA damage as concluded through correlation analysis. The cost-effective and eco-friendly biosynthesis of Cu-NPs with high antibacterial activities make them particularly attractive for drinking water disinfection.
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Affiliation(s)
- Qing Lv
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Baogang Zhang
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China.
| | - Xuan Xing
- College of Life and Environmental Science, Minzu University of China, Beijing 100081, PR China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, PR China
| | - Ruquan Cai
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Wei Wang
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Qian Gu
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
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Li H, Li B, Zhang Z, Zhu C, Tian Y, Ye J. Evolution of microbial communities during electrokinetic treatment of antibiotic-polluted soil. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 148:842-850. [PMID: 29197799 DOI: 10.1016/j.ecoenv.2017.11.057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/19/2017] [Accepted: 11/22/2017] [Indexed: 06/07/2023]
Abstract
The evolution of microbial communities during the electrokinetic treatment of antibiotic-polluted soil (EKA) was investigated with chlortetracycline (CTC), oxytetracycline (OTC) and tetracycline (TC) as template antibiotics. The total population of soil microorganisms was less affected during the electrokinetic process, while living anti-CTC, anti-OTC, anti-TC and anti-MIX bacteria were inactivated by 10.48%, 31.37%, 34.76%, and 22.08%, respectively, during the 7-day treatment compared with antibiotic-polluted soil without an electric field (NOE). Accordingly, samples with NOE treatment showed a higher Shannon index than those with EKA treatment, indicating a reduction of the microbial community diversity after electrokinetic processes. The major taxonomic phyla found in the samples of EKA and NOE treatment were Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. And the distribution of Actinobacteria, Cyanobacteria, and Chloroflexi was greatly decreased compared with blank soil. In the phylum Proteobacteria, the abundance of Alphaproteobacteria was greatly reduced in the soils supplemented with antibiotics (from 13.40% in blank soil to 6.43-10.16% after treatment); while Betaproteobacteria and Deltaproteobacteria showed a different trend with their abundance increased compared to blank soil, and Gammaproteobacteria remained unchanged for all treatments (2.36-2.78%). The varied trends for different classes indicated that the major bacterial groups changed with the treatments due to their different adaptability to the antibiotics as well as to the electric field. SulI being an exception, the reduction ratio of the observed antibiotic resistance genes (ARGs) including tetC, tetG, tetW, tetM, intI1, and sulII in the 0-2cm soil sampled with EKA versus NOE treatment reached 55.17%, 3.59%, 99.26%, 89.51%, 30.40%, and 27.92%, respectively. Finally, correlation analysis was conducted between antibiotic-resistant bacteria, ARGs and taxonomic bacterial classes. It was found that sulII was the most representative of many different bacteria among the seven ARGs studied. This is the first report on the changes in microbial communities before and after EKA, and the present results demonstrated that the application of EKA is a useful and effective approach to suppressing both antibiotic resistant microorganisms and ARGs.
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Affiliation(s)
- Hongna Li
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
| | - Binxu Li
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Zhiguo Zhang
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Changxiong Zhu
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yunlong Tian
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Jing Ye
- Agricultural Clean Watershed Research Group, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
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34
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Ghasemian S, Asadishad B, Omanovic S, Tufenkji N. Electrochemical disinfection of bacteria-laden water using antimony-doped tin-tungsten-oxide electrodes. WATER RESEARCH 2017; 126:299-307. [PMID: 28965032 DOI: 10.1016/j.watres.2017.09.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/04/2017] [Accepted: 09/16/2017] [Indexed: 06/07/2023]
Abstract
Electrochemical disinfection has been shown to be an efficient method with a shortrequired contact time for treatment of drinking water supplies, industrial raw water supplies, liquid foodstuffs, and wastewater effluents. In the present work, the electrochemical disinfection of saline water contaminated with bacteria was investigated in chloride-containing solutions using Sb-doped Sn80%-W20%-oxide anodes. The influence of current density, bacterial load, initial chloride concentration, solution pH, and the type of bacteria (E. coli D21, E. coli O157:H7, and E. faecalis) on disinfection efficacy was systematically examined. The impact of natural organic matter and a radical scavenger on the disinfection process was also examined. The electrochemical system was highly effective in bacterial inactivation for a 0.1 M NaCl solution contaminated with ∼107 CFU/mL bacteria by applying a current density ≥1 mA/cm2 through the cell.100% inactivation of E. coli D21 was achieved with a contact time of less than 60 s and power consumption of 48 Wh/m3, by applying a current density of 6 mA/cm2 in a 0.1 M NaCl solution contaminated with ∼107 CFU/mL. Reactive chlorine species as well as reactive oxygen species (e.g. hydroxyl radicals) generated in situ during the electrochemical process were determined to be responsible for inactivation of bacteria.
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Affiliation(s)
- Saloumeh Ghasemian
- Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0C5, Canada.
| | - Bahareh Asadishad
- Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0C5, Canada
| | - Sasha Omanovic
- Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0C5, Canada
| | - Nathalie Tufenkji
- Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0C5, Canada
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35
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He H, Huang B, Fu G, Du Y, Xiong D, Lai C, Pan X. Coupling electrochemical and biological methods for 17α-ethinylestradiol removal from water by different microorganisms. JOURNAL OF HAZARDOUS MATERIALS 2017; 340:120-129. [PMID: 28715735 DOI: 10.1016/j.jhazmat.2017.06.070] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/03/2017] [Accepted: 06/28/2017] [Indexed: 06/07/2023]
Abstract
17α-ethynylestradiol (EE2) has become a growing concern due to its wide detection and high estrogenic potency. However, biodegradation of EE2 with individual microorganisms demonstrated poor degradation efficiency ranging from 10.3% to 45.8% in 120h. Now, a system combining electrochemical with biological degradation was tested for its ability to remove EE2 from aqueous solution. EE2 removal is promoted at high dissolved oxygen concentrations and low pH when electrochemical methods alone are employed. Coupling electrochemical methods with anaerobic bacteria can improve the EE2 removal after 90min to as much as 81.9% with a reaction rate constant of 0.0195min-1. An electric current of 100mA at pH5.5 inhibits the growth of most microbial species, but Shewanella and Aeromonas survive well. They can enhance the efficiency of direct electron transfer efficiency between the bacteria and the electrodes, promoting EE2 degradation. This study provided a theoretical basis for the future applicability of bioelectrochemical technology to remove steroids from waste water.
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Affiliation(s)
- Huan He
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Bin Huang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China.
| | - Gen Fu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yanan Du
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Dan Xiong
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Chaochao Lai
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Xuejun Pan
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
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Frontistis Z, Antonopoulou M, Venieri D, Konstantinou I, Mantzavinos D. Boron-doped diamond oxidation of amoxicillin pharmaceutical formulation: Statistical evaluation of operating parameters, reaction pathways and antibacterial activity. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 195:100-109. [PMID: 27117507 DOI: 10.1016/j.jenvman.2016.04.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/12/2016] [Accepted: 04/12/2016] [Indexed: 05/03/2023]
Abstract
The electrochemical oxidation of a commercial amoxicillin formulation over a boron-doped diamond (BDD) anode was investigated. The effect of initial COD concentration (1-2 g/L), current density (30-50 mA/cm2), treatment time (15-90 min), initial pH (3-9) and electrolyte concentration (2-4 g/L NaCl) on COD removal was assessed through a factorial design methodology. For the range of conditions in question, the first three single effects, as well as the interaction between COD and time were the most important ones in terms of mass of COD removed. Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) was employed to identify major transformation by-products (TBPs); thirteen compounds were detected as TBPs of AMX electrochemical degradation, while several others appear in the original formulation. AMX degradation occurs though the following pathways: (i) hydroxylation mainly in the benzoic ring, (ii) opening of β-lactam ring followed by decarboxylation, hydroxylation and re-arrangement, and (iii) bond cleavage between the carbons of amino and amide groups. Furthermore, the process is accompanied by the release of several ions, i.e. nitrate, sulfate and ammonium. The antibiotic activity of AMX up to 1000 mg/L was tested against Klebsiella pneumoniae and Enterococcus faecalis reference strains; both bacteria are completely inactivated at this concentration but the activity is reduced substantially at lower concentrations. Oxidized samples still exhibit some antibacterial activity (50-60%) which is due to TBPs and active chlorine species present in the liquid phase. The latter are generated from chloride ions and enhance considerably AMX degradation rates.
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Affiliation(s)
- Zacharias Frontistis
- Department of Chemical Engineering, University of Patras, Caratheodory 1, University Campus, GR-26504 Patras, Greece
| | - Maria Antonopoulou
- Department of Environmental & Natural Resources Management, University of Patras, 2 Seferi St., GR-30100 Agrinio, Greece
| | - Danae Venieri
- School of Environmental Engineering, Technical University of Crete, Polytechneioupolis, GR-73100 Chania, Greece
| | | | - Dionissios Mantzavinos
- Department of Chemical Engineering, University of Patras, Caratheodory 1, University Campus, GR-26504 Patras, Greece.
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Bruguera-Casamada C, Sirés I, Prieto MJ, Brillas E, Araujo RM. The ability of electrochemical oxidation with a BDD anode to inactivate Gram-negative and Gram-positive bacteria in low conductivity sulfate medium. CHEMOSPHERE 2016; 163:516-524. [PMID: 27567151 DOI: 10.1016/j.chemosphere.2016.08.042] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/04/2016] [Accepted: 08/08/2016] [Indexed: 05/03/2023]
Abstract
The disinfection of 100 mL of synthetic water containing 7 mM Na2SO4 with 10(6) CFU mL(-1) of either Gram-negative or Gram-positive bacteria has been studied by electrochemical oxidation. The electrolytic cell was a stirred tank reactor equipped with a boron-doped diamond (BDD) anode and a stainless steel cathode and the trials were performed at acidic and neutral pH, at 33.3 mA cm(-2) and 25 °C. Reactive oxygen species, pre-eminently hydroxyl radicals, were efficiently produced in both media from water oxidation at the BDD anode and the bacteria concentration was reduced by ≥ 5 log units after 60 min of electrolysis, thus constituting a good chlorine-free disinfection treatment. All the inactivation kinetics were described by a logistic model, with no significant statistical differences between acidic and neutral suspensions. The electrochemical disinfection with BDD was very effective for Gram-negative bacilli like Escherichia coli and Pseudomonas aeruginosa and Gram-positive ones like Bacillus atrophaeus, whereas the Gram-positive cocci Staphylococcus aureus and Enterococcus hirae were more resistant. Thus, the latter organisms are a better choice than E. coli as process indicators. Scanning electron microscopy highlighted a transition from initial cells with standard morphology supported on clean filters to inactivated cells with a highly altered morphology lying on dirty filters with plenty of cellular debris. Larger damage was observed for Gram-negative cells compared to Gram-positive ones. The inactivation effect could then be related to the chemical composition of the outer layers of the cell structure along with the modification of the transmembrane potentials upon current passage.
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Affiliation(s)
- Carmina Bruguera-Casamada
- Departament de Microbiologia, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028 Barcelona, Spain
| | - Ignasi Sirés
- Laboratori d'Electroquímica dels Materials i del Medi Ambient, Departament de Química Física, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.
| | - María J Prieto
- Departament de Microbiologia, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028 Barcelona, Spain
| | - Enric Brillas
- Laboratori d'Electroquímica dels Materials i del Medi Ambient, Departament de Química Física, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Rosa M Araujo
- Departament de Microbiologia, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028 Barcelona, Spain.
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Singh RK, Philip L, Ramanujam S. Disinfection of water by pulsed power technique: a mechanistic perspective. RSC Adv 2016. [DOI: 10.1039/c5ra26941e] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A detailed sub-cellular level bacterial disinfection mechanism and perturbation of bacterial surface potential due to ROS/RNS in pulsed plasma treatment.
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Affiliation(s)
- Raj Kamal Singh
- Department of Civil Engineering
- Indian Institute of Technology Madras
- Chennai
- India – 600036
| | - Ligy Philip
- Department of Civil Engineering
- Indian Institute of Technology Madras
- Chennai
- India – 600036
| | - Sarathi Ramanujam
- Department of Electrical Engineering
- Indian Institute of Technology Madras
- Chennai
- India – 600036
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