1
|
Ye JC, Zhao QS, Liang JW, Wang XX, Zhan ZX, Du H, Cheng JL, Xiang L, Feng NX, Liu BL, Li YW, Li H, Cai QY, Zhao HM, Mo CH. Bioremediation of aniline aerofloat wastewater at extreme conditions using a novel isolate Burkholderia sp. WX-6 immobilized on biochar. J Hazard Mater 2023; 456:131668. [PMID: 37224713 DOI: 10.1016/j.jhazmat.2023.131668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/17/2023] [Accepted: 05/19/2023] [Indexed: 05/26/2023]
Abstract
Aniline aerofloat (AAF) is a refractory organic pollutant in floatation wastewater. Little information is currently available on its biodegradation. In this study, a novel AAF-degrading strain named Burkholderia sp. WX-6 was isolated from mining sludge. The strain could degrade more than 80% of AAF at different initial concentrations (100-1000 mg/L) within 72 h. AAF degrading curves were fitted well with the four-parameter logistic model (R2 >0.97), with the degrading half-life ranging from 16.39 to 35.55 h. This strain harbors metabolic pathway for complete degradation of AAF and is resistant to salt, alkali, and heavy metals. Immobilization of the strain on biochar enhanced both tolerance to extreme conditions and AAF removal, with up to 88% of AAF removal rate in simulated wastewater under alkaline (pH 9.5) or heavy metal pollution condition. In addition, the biochar-immobilized bacteria removed 59.4% of COD in the wastewater containing AAF and mixed metal ions within 144 h, significantly (P < 0.05) higher than those by free bacteria (42.6%) and biochar (48.2%) only. This work is helpful to understand AAF biodegradation mechanism and provides viable references for developing practical biotreatment technique of mining wastewater.
Collapse
Affiliation(s)
- Jin-Cheng Ye
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Qiu-Shi Zhao
- School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jin-Wei Liang
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Xiao-Xiao Wang
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Zhen-Xuan Zhan
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Huan Du
- Guangzhou Customs Technology Center, Guangzhou 510632, China
| | - Ji-Liang Cheng
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Lei Xiang
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Nai-Xian Feng
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Bai-Lin Liu
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Yan-Wen Li
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hui Li
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Quan-Ying Cai
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hai-Ming Zhao
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, Guangzhou 510642, China.
| | - Ce-Hui Mo
- Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
| |
Collapse
|
2
|
Mulla S, Ludlam AR, Elragig A, Slack C, Balklava Z, Stich M, Cheong A. A biphasic model of lifespan in nematode Caenorhabditis elegans worm. R Soc Open Sci 2023; 10:220991. [PMID: 36756060 PMCID: PMC9890093 DOI: 10.1098/rsos.220991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 01/11/2023] [Indexed: 06/18/2023]
Abstract
Ageing research focuses on identifying lifespan modifiers and understanding and appropriately interpreting their effects. One of the most relevant quantities being studied is the shape of the survival curve that can reveal crucial information on the mechanism of action. Here, we introduce a bilogistic model to describe the shape of the lifespan curves of Caenorhabditis elegans populations. Using the corrected Akaike information criterion and the RMSE as goodness-of-fit tests, we show that the bilogistic model provides a better fit to the experimental data from nematode worms than other mathematical models and can identify and confirm biphasic lifespan data. Our parametric model offers a method to interpret replicate experiments data in terms of the shape parameters of the lifespan curve and enables robust statistical analysis of intra- and inter-group variance. We apply the model to novel lifespan data from C. elegans and Drosophila melanogaster and provide a rational statistical analysis of lifespan modifiers such as temperature and daf-16/FOXO mutation.
Collapse
Affiliation(s)
- Suhayl Mulla
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
- Engineering and Applied Science, Aston University, Birmingham B4 7ET, UK
| | - Adele R. Ludlam
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| | - Aiman Elragig
- Engineering and Applied Science, Aston University, Birmingham B4 7ET, UK
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London W1S 4BS, UK
| | - Cathy Slack
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| | - Zita Balklava
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| | - Michael Stich
- Engineering and Applied Science, Aston University, Birmingham B4 7ET, UK
- Departmento de Matemática Aplicada, Ciencia e Ingeniería de los Materiales y Tecnología Electrónica, Universidad Rey Juan Carlos, 28933 Móstoles, Spain
| | - Alex Cheong
- Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
| |
Collapse
|
3
|
Dini V, Esposito G, Sacconi A, D'Andrea M, Tabocchini MA, Anello P, Ricci-Vitiani L, Buccarelli M, Pallini R, Strigari L. Effectiveness of Flattening-Filter-Free versus Flattened Beams in V79 and Glioblastoma Patient-Derived Stem-like Cells. Int J Mol Sci 2023; 24. [PMID: 36674623 DOI: 10.3390/ijms24021107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/31/2022] [Accepted: 01/03/2023] [Indexed: 01/09/2023] Open
Abstract
Literature data on the administration of conventional high-dose beams with (FF) or without flattening filters (FFF) show conflicting results on biological effects at the cellular level. To contribute to this field, we irradiated V79 Chinese hamster lung fibroblasts and two patient-derived glioblastoma stem-like cell lines (GSCs-named #1 and #83) using a clinical 10 MV accelerator with FF (at 4 Gy/min) and FFF (at two dose rates 4 and 24 Gy/min). Cell killing and DNA damage induction, determined using the γ-H2AX assay, and gene expression were studied. No significant differences in the early survival of V79 cells were observed as a function of dose rates and FF or FFF beams, while a trend of reduction in late survival was observed at the highest dose rate with the FFF beam. GSCs showed similar survival levels as a function of dose rates, both delivered in the FFF regimen. The amount of DNA damage measured for both dose rates after 2 h was much higher in line #1 than in line #83, with statistically significant differences between the two dose rates only in line #83. The gene expression analysis of the two GSC lines indicates gene signatures mimicking the prognosis of glioblastoma (GBM) patients derived from a public database. Overall, the results support the current use of FFF and highlight the possibility of identifying patients with candidate gene signatures that could benefit from irradiation with FFF beams at a high dose rate.
Collapse
|
4
|
HAFSAN H, HUY DTN, VAN TUAN P, MAHMUDIONO T, DINKU T, NASIRIN C, SUTARTO S, KADHIM MM, SINGH K, AL-MAWLAWI ZS. Modelling of inactivation of microorganisms in the process of sterilization using high pressure supercritical fluids. Food Sci Technol 2023. [DOI: 10.1590/fst.111621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Affiliation(s)
- Hafsan HAFSAN
- Universitas Islam Negeri Alauddin Makassar, Indonesia
| | - Dinh Tran Ngoc HUY
- Banking University HCMC, Vietnam; International University of Japan, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Todorova Y, Benova E, Marinova P, Yotinov I, Bogdanov T, Topalova Y. Non-Thermal Atmospheric Plasma for Microbial Decontamination and Removal of Hazardous Chemicals: An Overview in the Circular Economy Context with Data for Test Applications of Microwave Plasma Torch. Processes (Basel) 2022; 10:554. [DOI: 10.3390/pr10030554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The transformation of our linear “take-make-waste” system to a cyclic flow of materials and energy is a priority task for society, but the circular use of waste streams from one industry/sector as a material input for another must be completely safe. The need for new advanced technologies and methods ensuring both microbiological safety and the removal of potential chemical residues in used materials and products is urgent. Non-thermal atmospheric plasma (cold atmospheric plasma—CAP) has recently attracted great research interest as an alternative for operative solutions of problems related to safety and quality control. CAP is a powerful tool for the inactivation of different hazardous microorganisms and viruses, and the effective decontamination of surfaces and liquids has been demonstrated. Additionally, the plasma’s active components are strong oxidizers and their synergetic effect can lead to the degradation of toxic chemical compounds such as phenols and azo-dyes.
Collapse
|
6
|
Chuang S, Sheen S. High pressure processing of raw meat with essential oils-microbial survival, meat quality, and models: A review. Food Control 2022; 132:108529. [DOI: 10.1016/j.foodcont.2021.108529] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
7
|
Verheyen D, Van Impe JFM. The Inclusion of the Food Microstructural Influence in Predictive Microbiology: State-of-the-Art. Foods 2021; 10:foods10092119. [PMID: 34574229 PMCID: PMC8468028 DOI: 10.3390/foods10092119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/27/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022] Open
Abstract
Predictive microbiology has steadily evolved into one of the most important tools to assess and control the microbiological safety of food products. Predictive models were traditionally developed based on experiments in liquid laboratory media, meaning that food microstructural effects were not represented in these models. Since food microstructure is known to exert a significant effect on microbial growth and inactivation dynamics, the applicability of predictive models is limited if food microstructure is not taken into account. Over the last 10-20 years, researchers, therefore, developed a variety of models that do include certain food microstructural influences. This review provides an overview of the most notable microstructure-including models which were developed over the years, both for microbial growth and inactivation.
Collapse
Affiliation(s)
- Davy Verheyen
- BioTeC+, Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Gebroeders de Smetstraat 1, 9000 Ghent, Belgium;
- OPTEC, Optimization in Engineering Center-of-Excellence, KU Leuven, 3000 Leuven, Belgium
- CPMF2, Flemish Cluster Predictive Microbiology in Foods—www.cpmf2.be, 9000 Ghent, Belgium
| | - Jan F. M. Van Impe
- BioTeC+, Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Gebroeders de Smetstraat 1, 9000 Ghent, Belgium;
- OPTEC, Optimization in Engineering Center-of-Excellence, KU Leuven, 3000 Leuven, Belgium
- CPMF2, Flemish Cluster Predictive Microbiology in Foods—www.cpmf2.be, 9000 Ghent, Belgium
- Correspondence:
| |
Collapse
|
8
|
Tuly SS, Mahiuddin M, Karim A. Mathematical modeling of nutritional, color, texture, and microbial activity changes in fruit and vegetables during drying: A critical review. Crit Rev Food Sci Nutr 2021; 63:1877-1900. [PMID: 34459302 DOI: 10.1080/10408398.2021.1969533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Retention of quality attributes during drying of fruit and vegetables is a prime concern since the product's acceptability depends on the overall quality; particularly on the nutritional, color, and physical attributes. However, these quality parameters deteriorate during drying. Food quality changes are strongly related to the drying conditions and researchers have attempted to develop mathematical models to understand these relationships. A better insight toward the degradation of quality attributes is crucial for making real predictions and minimizing the quality deterioration. The previous empirical quality models employed kinetic modeling approaches to describe the quality changes and therefore, lack the realistic understanding of fundamental transport mechanisms. In order to develop a physics based mathematical model for the prediction of quality changes during drying, an in-depth understanding of research progress made toward this direction is indispensable. Therefore, the main goal of this paper is to present a critical review of the mathematical models developed and applied to describe the degradation kinetics of nutritional, color, and texture attributes during drying of fruit and vegetables and microbial growth model during storage. This review also presents the advantages and drawbacks of the existing models along with their industrial relevance. Finally, future research propositions toward developing physics-based mathematical model are presented.
Collapse
Affiliation(s)
- Sumaiya Sadika Tuly
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Md Mahiuddin
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Azharul Karim
- Faculty of Science and Engineering, Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| |
Collapse
|
9
|
Linsak DT, Kese D, Broznic D, Lusic DV, Cenov A, Moric M, Gobin I. Sea water whirlpool spa as a source of Legionella infection. J Water Health 2021; 19:242-253. [PMID: 33901021 DOI: 10.2166/wh.2021.150] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Bacterial pneumonia caused by the inhalation of aerosols contaminated with Legionella spp. is also known as Legionnaires' disease. In this study, we report a case of pneumonia caused by Legionella pneumophila sg.1 in a 58-year-old man who visited a sea water-filled whirlpool within a hotel and spa complex. The patient's Legionella urine antigen test was positive for L. pneumophila sg.1. During the field study, samples were taken from both the outdoor and indoor sea water-filled pools. Samples from the whirlpool were culture positive for L. pneumophila sg.1. Typing results indicated sea water isolate belonged to Sequence type ST82 and Allentown/France MAb subgroup. In vitro experiments showed that L. pneumophila strains are able to survive within sea water up to 7 days, and survival time is prolonged with sea water dilution. Also, our results indicate that L. pneumophila Allentown strain was the most resistant to adverse conditions in sea water with the highest values of DT50 (420 min) and DT90 (1,396 min). The possible source of infection was adding potable water for filling up the whirlpool. The survival of the L. pneumophila in additionally conditioned sea water should be considered in a further study.
Collapse
Affiliation(s)
- Dijana Tomic Linsak
- Faculty of Medicine, Department of Health Ecology, University of Rijeka, Brace Branchetta 20, 51000 Rijeka, Croatia E-mail: ; Teaching Institute of Public Health of Primorje-Gorski Kotar County, Kresimirova 52a, 51000 Rijeka, Croatia
| | - Darja Kese
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Zaloska 4, 1000 Ljubljana, Slovenia
| | - Dalibor Broznic
- Faculty of Medicine, Department of Medical Chemistry, Biochemistry and Clinical Chemistry, University of Rijeka, Brace Branchetta 20, 51000 Rijeka, Croatia
| | - Darija Vukic Lusic
- Faculty of Medicine, Department of Health Ecology, University of Rijeka, Brace Branchetta 20, 51000 Rijeka, Croatia E-mail: ; Teaching Institute of Public Health of Primorje-Gorski Kotar County, Kresimirova 52a, 51000 Rijeka, Croatia
| | - Arijana Cenov
- Teaching Institute of Public Health of Primorje-Gorski Kotar County, Kresimirova 52a, 51000 Rijeka, Croatia
| | - Milan Moric
- Teaching Institute of Public Health of Primorje-Gorski Kotar County, Kresimirova 52a, 51000 Rijeka, Croatia
| | - Ivana Gobin
- Faculty of Medicine, Department of Microbiology, University of Rijeka, Brace Branchetta 20, 51000 Rijeka, Croatia
| |
Collapse
|
10
|
Acuff JC, Wu J, Marik C, Waterman K, Gallagher D, Huang H, Williams RC, Ponder MA. Thermal inactivation of Salmonella, Shiga toxin-producing Escherichia coli, Listeria monocytogenes, and a surrogate (Pediococcus acidilactici) on raisins, apricot halves, and macadamia nuts using vacuum-steam pasteurization. Int J Food Microbiol 2020; 333:108814. [PMID: 32805576 DOI: 10.1016/j.ijfoodmicro.2020.108814] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 06/17/2020] [Accepted: 08/02/2020] [Indexed: 11/20/2022]
Abstract
Salmonella, Shiga toxin-producing Escherichia coli (STEC), and Listeria monocytogenes have been isolated from low water activity foods (LWAF), where they may survive for extended periods. The ready-to-eat nature of many LWAF, such as dried fruits and nuts, warrants effective post-harvest thermal treatment for the reduction of pathogens such as low-temperature, saturated steam, also known as vacuum-assisted steam pasteurization. The objective of this study was to determine reductions of Salmonella, STEC, L. monocytogenes, and a possible surrogate (Pediococcus acidilactici) on dried apricot halves, whole macadamia nuts, and raisins after treatment with vacuum-assisted steam at three temperatures (62 °C, 72 °C, or 82 °C) and multiple time intervals. Bacterial inactivation was variable between commodities, with higher temperatures and longer times necessary to achieve comparable reductions of pathogens on apricot halves and macadamia nuts compared to raisins. Reductions of the tested pathogens were comparable; therefore, one species was not more resistant than the others. Pathogens were reduced by 5-log CFU/g on apricot halves after 20 min at 72 °C and after 5 min at 82 °C. Longer treatment times were necessary to achieve reductions of each pathogen on macadamia nuts. Pathogens were reduced by nearly 5 log CFU/g on macadamia nuts after 38 min at 72 °C (4.6-6.5 log CFU/g) and after 12 min at 82 °C (4.9-5.7 log CFU/g). Reductions of pathogens on raisins were achieved at lower temperatures than necessary for the other foods. A 5-log reduction for each of the pathogens (CFU/g) on raisins occurred after 20 min at 62 °C and after 5 min at 72 °C. Overall, the reductions of the pathogens exceeded those of P. acidilactici on both the dried fruits and macadamia nuts. Statistically significant differences, indicating greater confidence as a conservative surrogate, were observed at lower treatment temperatures. Inactivation kinetics were modeled for each pathogen on each food type and temperature. Bacterial survival was best described by the Weibull model for raisins and macadamia nuts, while the Gompertz model best described reductions on apricot halves according to Akaike information criterion (AIC) and root-mean-square error (RMSE) evaluations. Water activity and moisture content were increased due to the treatments, which could be addressed through implementation of drying steps. Thermal inactivation kinetic models and 5-log reduction parameters can help food processors design and evaluate similar vacuum-assisted steam interventions to comply with FSMA regulations and preventive control plans. However, results or model predictions should not be extrapolated to assume the safety of other types of foods.
Collapse
Affiliation(s)
- Jennifer C Acuff
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Jian Wu
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Claire Marik
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Kim Waterman
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Daniel Gallagher
- Virginia Tech, Civil and Environmental Engineering Department, 409 Durham Hall, Blacksburg, VA 24061, USA
| | - Haibo Huang
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Robert C Williams
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA
| | - Monica A Ponder
- Virginia Tech, Food Science and Technology, 1230 Washington St., Blacksburg, VA 24061, USA.
| |
Collapse
|
11
|
Yap TF, Liu Z, Shveda RA, Preston DJ. A predictive model of the temperature-dependent inactivation of coronaviruses. Appl Phys Lett 2020; 117:060601. [PMID: 32817726 PMCID: PMC7428726 DOI: 10.1063/5.0020782] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 07/30/2020] [Indexed: 05/06/2023]
Abstract
The COVID-19 pandemic has stressed healthcare systems and supply lines, forcing medical doctors to risk infection by decontaminating and reusing single-use personal protective equipment. The uncertain future of the pandemic is compounded by limited data on the ability of the responsible virus, SARS-CoV-2, to survive across various climates, preventing epidemiologists from accurately modeling its spread. However, a detailed thermodynamic analysis of experimental data on the inactivation of SARS-CoV-2 and related coronaviruses can enable a fundamental understanding of their thermal degradation that will help model the COVID-19 pandemic and mitigate future outbreaks. This work introduces a thermodynamic model that synthesizes existing data into an analytical framework built on first principles, including the rate law for a first-order reaction and the Arrhenius equation, to accurately predict the temperature-dependent inactivation of coronaviruses. The model provides much-needed thermal decontamination guidelines for personal protective equipment, including masks. For example, at 70 °C, a 3-log (99.9%) reduction in virus concentration can be achieved, on average, in 3 min (under the same conditions, a more conservative decontamination time of 39 min represents the upper limit of a 95% interval) and can be performed in most home ovens without reducing the efficacy of typical N95 masks as shown in recent experimental reports. This model will also allow for epidemiologists to incorporate the lifetime of SARS-CoV-2 as a continuous function of environmental temperature into models forecasting the spread of the pandemic across different climates and seasons.
Collapse
Affiliation(s)
- Te Faye Yap
- Department of Mechanical Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, USA
| | - Zhen Liu
- Department of Mechanical Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, USA
| | - Rachel A. Shveda
- Department of Mechanical Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, USA
| | - Daniel J. Preston
- Department of Mechanical Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, USA
| |
Collapse
|
12
|
Aspridou Z, Koutsoumanis K. Variability in microbial inactivation: From deterministic Bigelow model to probability distribution of single cell inactivation times. Food Res Int 2020; 137:109579. [PMID: 33233190 DOI: 10.1016/j.foodres.2020.109579] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 07/02/2020] [Accepted: 07/20/2020] [Indexed: 11/29/2022]
Abstract
Phenotypic heterogeneity seems to be an important component leading to biological individuality and is of great importance in the case of microbial inactivation. Bacterial cells are characterized by their own resistance to stresses. This inherent stochasticity is reflected in microbial survival curve which, in this context, can be considered as cumulative probability distribution of lethal events. The objective of the present study was to present an overview on the assessment and quantification of variability in microbial inactivation originating from single cells and discuss this heterogeneity in the context of predicting microbial behavior and Risk assessment studies. The detailed knowledge of the distribution of the single cells' inactivation times can be the basis for stochastic inactivation models which, in turn, may be employed in a risk - based food safety approach.
Collapse
Affiliation(s)
- Zafiro Aspridou
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Forestry and Natural Environment, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Konstantinos Koutsoumanis
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Forestry and Natural Environment, Aristotle University of Thessaloniki, Thessaloniki, Greece.
| |
Collapse
|
13
|
Ochoa-velasco CE, Ávila-sosa R, Hernández-carranza P, Ruíz-espinosa H, Ruiz-lópez II, Guerrero-beltrán JÁ. Mathematical Modeling Used to Evaluate the Effect of UV-C Light Treatment on Microorganisms in Liquid Foods. Food Eng Rev 2020; 12:290-308. [DOI: 10.1007/s12393-020-09219-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
|
14
|
Taiye Mustapha A, Zhou C, Amanor-Atiemoh R, Owusu-Fordjour M, Wahia H, Abiola Fakayode O, Ma H. Kinetic modeling of inactivation of natural microbiota and Escherichia coli on cherry tomato treated with fixed multi-frequency sonication. Ultrason Sonochem 2020; 64:105035. [PMID: 32106069 DOI: 10.1016/j.ultsonch.2020.105035] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 02/12/2020] [Accepted: 02/12/2020] [Indexed: 05/03/2023]
Abstract
The suitability of some non-linear kinetic models (Weibull {with or without tail}, Log-linear, Log-linear shoulder {with or without tail}, Biphasic linear, Logistic, Multi-target and Single-target models) were evaluated to determine the inactivation kinetics of inoculated E. coli, and natural microbiota (i.e. mesophilic aerobic bacteria, and mold and yeast) on cherry tomato treated with fixed multi-frequency ultrasound. Almost all the studied model fitted well (R2 ≥ 0.9) for the inactivation kinetics; however, the Weibull, Log-linear shoulder, and Biphasic linear model showed the highest statistical parameters (0.9 ≤ adj. R2 ≤ 0.99 and smallest RMSE and SSE values). All the three models could be used to compare the kinetic behavior of E. coli and the first two models for the kinetic behavior of mesophilic aerobic bacteria and mold and yeast during sonication treatment. Two distinctive inactivation curves were obtained for the mono-frequency and the multi-frequency (dual and tri-frequency) for all the microbial inactivation. The remarkable results obtained for dual and tri-frequency sonication shows to be an effective and promising alternative to the traditional microbial inactivation techniques and the common practice of using ultrasound with other sanitizing methods.
Collapse
Affiliation(s)
- Abdullateef Taiye Mustapha
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Cunshan Zhou
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China; School of Biological and Food Engineering, Chuzhou University, Chuzhou, 239000, People's Republic of China.
| | - Robert Amanor-Atiemoh
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Mariam Owusu-Fordjour
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Hafida Wahia
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Olugbenga Abiola Fakayode
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| | - Haile Ma
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China
| |
Collapse
|
15
|
Dean K, Wissler A, Hernandez-Suarez JS, Nejadhashemi AP, Mitchell J. Modeling the persistence of viruses in untreated groundwater. Sci Total Environ 2020; 717:134599. [PMID: 31836219 DOI: 10.1016/j.scitotenv.2019.134599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/18/2019] [Accepted: 09/20/2019] [Indexed: 05/21/2023]
Abstract
Several factors can affect virus behavior and persistence in water sources. Historically linear models have been used to describe persistence over time; however, these models do not consider all of the factors that can affect inactivation kinetics or the observed patterns of decay. Meanwhile, applying the appropriate persistence model is critical for ensuring that decision makers are minimizing human health risk in the event of contamination and exposure to contaminated groundwater. Therefore, to address uncertainty in predictions of decay or virus concentrations over time, this study fit seventeen different linear and nonlinear mathematical models to persistence data from a previously conducted sampling study on drinking water wells throughout the United States. The models were fit using Maximum Likelihood Estimation and the best fitting models were determined by the Bayesian Information Criterion. The purpose of the study was to identify the best model for estimating decay of viruses in groundwater and to determine if model uncertainty contributes to erroneous predictions of viral contamination when only conventional models are considered. For the datasets analyzed in this study, the Juneja and Marks models and the exponential damped model were more representative of the persistence of viruses in groundwater than the traditionally used linear models. The results from this study were then evaluated with classification trees in order to identify more relevant modeling methodology for future research. The classification trees aid in narrowing the scope of appropriate persistence models based on characteristics of the experimental conditions and water sampled.
Collapse
Affiliation(s)
- Kara Dean
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI, United States
| | - Austin Wissler
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI, United States; Water Resources Graduate Program, Oregon State University, Corvallis, OR, United States
| | - J Sebastian Hernandez-Suarez
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI, United States
| | - A Pouyan Nejadhashemi
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI, United States
| | - Jade Mitchell
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI, United States.
| |
Collapse
|
16
|
Aragón-Rojas S, Hernández-Álvarez AJ, Mainville I, Arcand Y, Quintanilla-Carvajal MX. Effect of the carrier material, drying technology and dissolution media on the viability of Lactobacillus fermentum K73 during simulated gastrointestinal transit. Food Funct 2020; 11:2339-2348. [PMID: 32118211 DOI: 10.1039/c9fo01091b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The goal of this study was to determine the effect of the carrier material, drying technology and dissolution media during the passage of L. fermentum K73 through a dynamic in vitro digestion system (IViDiS). The carrier materials were (i) culture medium with growing micro-organisms and (ii) culture medium with maltodextrin : sweet whey [0.6 : 0.4]. The carrier materials were dried by spray-drying and freeze-drying to obtain four types of powders. The dissolution media consisted of water and 1% fat milk. The powders were tested using an in vitro dynamic digestion system (IViDiS). The results showed that powders derived from culture medium had the highest protective effect on the viability of L. fermentum K73 in both dissolution media and that survival increased when the powders were tested in milk. The modified Gompertz model was used to model L. fermentum K73 behaviour during the digestion process. The model showed that cells entrapped in culture medium had the longest lag phase and the slowest inactivation rate when evaluated in milk.
Collapse
Affiliation(s)
- Stephania Aragón-Rojas
- Faculty of Engineering, University of La Sabana, Campus del Puente del Común, Km. 7, Autopista Norte de Bogotá, Chía, Cundinamarca, Colombia.
| | | | | | | | | |
Collapse
|
17
|
Wang T, Dong J, Yin H, Zhang G. Blue light therapy to treat candida vaginitis with comparisons of three wavelengths: an in vitro study. Lasers Med Sci 2020; 35:1329-1339. [PMID: 31900692 DOI: 10.1007/s10103-019-02928-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 11/27/2019] [Indexed: 01/31/2023]
Abstract
Anti-fungal blue light (ABL) therapies have been widely studied to treat various microbial infections in the literature. The blue light with wavelengths ranging from 400 to 470 nm has been reported to be effective to inhibit various kinds of bacteria and fungi. The existing studies usually report the viability rates of the pathogens under the irradiation of the blue light with different dosage parameters. However, to the best of our knowledge, there is still no work especially focusing on studying the effect of ABL therapies on treating candida vaginitis, where it is important to study the viability of both the Candida albicans (C. albicans) and the human vaginal epithelial cells. It is the purpose of this work to conduct ABL experiments on both of these two cells, analyze the effects, and determine the best ABL wavelength out of three candidates, i.e., 405-nm, 415-nm, and 450-nm wavelength. The viability rates of the C. albicans and the human vaginal epithelial cells irradiated by the three blue LED light sources were measured, whose irradiance (power density) were all set to 50 mW/cm2. The dynamic viability models of the C. albicans and the epithelial cells were built based on the experimental data. Moreover, in this work, we also built a functional relationship between the viability of these two types of cells, by which we further compared the effects of the blue light irradiation on both the C. albicans and vaginal epithelial cells. The experimental data showed that when an approximately 80% inhibiting rate of the C. albicans was achieved, the survival rates of the epithelial cells were 0.6700, 0.7748, and 0.6027, respectively for the treatment by the 405-nm, 415-nm, and 450-nm wavelength light. On the other hand, by simulating the functional relationship between the viability of the two types of cells, the survival rates of the epithelial cells became 0.5783, 0.6898, and 0.1918 respectively using the 405-nm, 415-nm and 450-nm wavelength light, when the C. albicans was completely inhibited. Therefore, both the experimental data and the model simulation results have demonstrated that the 415-nm light has a more effective anti-fungal result with less damage to the epithelial cells than the 405-nm and 450-nm light.
Collapse
Affiliation(s)
- Tianfeng Wang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Jianfei Dong
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.
| | - Huancai Yin
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Guoqi Zhang
- Department of Microelectronics, Delft University of Technology, Delft, The Netherlands
| |
Collapse
|
18
|
Kowalski W, Bahnfleth W, Raguse M, Moeller R. The cluster model of ultraviolet disinfection explains tailing kinetics. J Appl Microbiol 2019; 128:1003-1014. [DOI: 10.1111/jam.14527] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 11/06/2019] [Accepted: 11/20/2019] [Indexed: 01/27/2023]
Affiliation(s)
| | - W.P. Bahnfleth
- The Pennsylvania State University University Park PA USA
| | - M. Raguse
- Space Microbiology Research Group Radiation Biology Department German Aerospace Center (DLR e.V.) Institute of Aerospace Medicine Cologne Germany
| | - R. Moeller
- Space Microbiology Research Group Radiation Biology Department German Aerospace Center (DLR e.V.) Institute of Aerospace Medicine Cologne Germany
| |
Collapse
|
19
|
Feliciano RJ, Gabriel AA. Juice composition, physicochemistry, and efficacy of ultraviolet radiation against Cryptococcus albidus. J Food Compost Anal 2019. [DOI: 10.1016/j.jfca.2019.103313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
20
|
Keklik NM. Treatment of pastirma with pulsed UV light: Modeling of Staphylococcus aureus inactivation and assessment of quality changes. FOOD SCI TECHNOL INT 2019; 26:185-198. [PMID: 31739685 DOI: 10.1177/1082013219889231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The efficacy of pulsed UV (PUV) light treatment carried out in a wide range of fluence was investigated on pastirma slices by characterizing Staphylococcus aureus inactivation using mathematical models and by assessing the treatment effects on quality attributes. Pastirma slices inoculated on top surface with S. aureus were subjected to pulsed UV light for 5, 15, 25, 35, and 45 s at 5, 8, and 13 cm from the quartz window. Although the 5 cm/45 s treatment (72.3 J/cm2) yielded a maximum reduction of 2.99 log cfu/cm2 for S. aureus, this treatment changed the color, moisture, and thiobarbituric acid-reactive substances (TBARS) values of pastirma significantly (p < 0.05). The quality of pastirma tended to change above 20 J/cm2, below which the highest log reduction of S. aureus was ∼1.3 log cfu/cm2 obtained after the 8 cm/15 s treatment (18 J/cm2). Kamau's model provided better fit to inactivation data (root mean square error: 0.049-0.116, Af: 1.013-1.046, R2: 0.991-0.999) than Cerf's and Weibull models.
Collapse
Affiliation(s)
- Nene Meltem Keklik
- Department of Food Engineering, Faculty of Engineering, Sivas Cumhuriyet University, Sivas, Turkey
| |
Collapse
|
21
|
Kondratenko V, Levshenko M, Petrov A, Pozdnyakova T, Trishkaneva M. Comparative evaluation of approaches to modelling kinetics of microbial thermal death as in the case of Alicyclobacillus acidoterrestris. Foods and Raw Materials 2019. [DOI: 10.21603/2308-4057-2019-2-348-363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Microbial death kinetics modelling is an integral stage of developing the food thermal sterilisation regimes. At present, a large number of models have been developed. Their properties are usually being accepted as adequate even beyond boundaries of experimental microbiological data zone. The wide range of primary models existence implies the lack of universality of each ones. This paper presents a comparative assessment of linear and nonlinear models of microbial death kinetics during the heat treatment of the Alicyclobacillus acidoterrestris spore form. The research allowed finding that single-phase primary models (as adjustable functions) are statistically acceptable for approximation of the experimental data: linear – the Bigelow’ the Bigelow as modified by Arrhenius and the Whiting-Buchanan models; and nonlinear – the Weibull, the Fermi, the Kamau, the Membre and the Augustin models. The analysis of them established a high degree of variability for extrapolative characteristics and, as a result, a marked empirical character of adjustable functions, i.e. unsatisfactory convergence of results for different models. This is presumably conditioned by the particularity and, in some cases, phenomenology of the functions themselves. Consequently, there is no reason to believe that the heat treatment regimes, developed on the basis of any of these empirical models, are the most effective. This analysis is the first link in arguing the necessity to initiate the research aimed at developing a new methodology for determining the regimes of food thermal sterilisation based on analysis of the fundamental factors such as ones defined spore germination activation and their resistance to external impact.
Collapse
|
22
|
Abstract
We present a simple growth model which was developed to explain Escherichia coli growth in batch culture. Optical density measurements are used to obtain E. coli growth curves for different inoculum sizes and nutrients concentrations. The model is described by two nonlinear mutually dependent differential equations that describe time evolution of bacteria and nutrients concentration. Introduction of the negative bacterium-bacterium interaction term is specific for the model and leads to the population decay. The proposed model describes entire experimental growth curves. The growth rate, as a function of initial nutrients concentration, follows the Monod function, whilst during the growth it decreases proportionally with the concentration of nutrients. The parameters in our equations can be related to the parameters of the logistic model. The proposed model can be applied to different E. coli strains and, because of the universality of the equations, might be applied to other bacterial strains.
Collapse
Affiliation(s)
- Lucija Krce
- Faculty of Science, Department of Physics, University of Split, Split, Croatia. Author to whom any correspondence should be addressed
| | | | | | | |
Collapse
|
23
|
Evelyn, Silva FV. Heat assisted HPP for the inactivation of bacteria, moulds and yeasts spores in foods: Log reductions and mathematical models. Trends Food Sci Technol 2019. [DOI: 10.1016/j.tifs.2019.03.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
24
|
Aragón-Rojas S, Quintanilla-Carvajal MX, Hernández-Sánchez H, Hernández-Álvarez AJ, Moreno FL. Encapsulation of Lactobacillus fermentum K73 by Refractance Window drying. Sci Rep 2019; 9:5625. [PMID: 30948743 PMCID: PMC6449500 DOI: 10.1038/s41598-019-42016-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 12/11/2018] [Indexed: 12/14/2022] Open
Abstract
The purpose of this work was to model the survival of the microorganism and the kinetics of drying during the encapsulation of Lactobacillus fermentum K73 by Refractance Window drying. A whey culture medium with and without addition of maltodextrin were used as encapsulation matrices. The microorganism with the encapsulation matrices was dried at three water temperatures (333, 343 and 353 K) until reaching balanced moisture. Microorganism survival and thin layer drying kinetics were studied by using mathematical models. Results showed that modified Gompertz model and Midilli model described the survival of the microorganism and the drying kinetics, respectively. The most favorable process conditions found with the mathematical modelling were a drying time of 2460 s, at a temperature of 353 K. At these conditions, a product with 9.1 Log CFU/g and a final humidity of 10% [wet basis] using the culture medium as encapsulation matrix was obtained. The result shows that Refractance Window can be applied to encapsulate the microorganism probiotic with a proper survival of the microorganism.
Collapse
Affiliation(s)
- Stephania Aragón-Rojas
- Universidad de La Sabana, Faculty of Engineering. Doctorado en Biociencias. Campus Universitario del Puente del Común, Km 7 Autopista Norte de Bogotá, Chía, Cundinamarca, Colombia
| | - María Ximena Quintanilla-Carvajal
- Universidad de La Sabana, Faculty of Engineering. Grupo de Investigación en Procesos Agroindustriales Campus Universitario del Puente del Común, Km 7 Autopista Norte de Bogotá, Chía, Cundinamarca, Colombia
| | - Humberto Hernández-Sánchez
- Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Av. Wilfrido Massieu esq. Cda. M. Stampa, UP Adolfo López Mateos, Ciudad de México, 07738, Mexico
| | | | - Fabian Leonardo Moreno
- Universidad de La Sabana, Faculty of Engineering. Grupo de Investigación en Procesos Agroindustriales Campus Universitario del Puente del Común, Km 7 Autopista Norte de Bogotá, Chía, Cundinamarca, Colombia.
| |
Collapse
|
25
|
|
26
|
Feliciano RJ, Estilo EEC, Nakano H, Gabriel AA. Ultraviolet-C resistance of selected spoilage yeasts in orange juice. Food Microbiol 2019; 78:73-81. [DOI: 10.1016/j.fm.2018.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 07/17/2018] [Accepted: 10/07/2018] [Indexed: 01/29/2023]
|
27
|
Zhang Y, Wei J, Yuan Y, Chen H, Dai L, Wang X, Yue T. Bactericidal effect of cold plasma on microbiota of commercial fish balls. INNOV FOOD SCI EMERG 2019. [DOI: 10.1016/j.ifset.2019.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
28
|
Feliciano RJ, Estilo EEC, Nakano H, Gabriel AA. Decimal reduction energies of UV-C-irradiated spoilage yeasts in coconut liquid endosperm. Int J Food Microbiol 2019; 290:170-179. [PMID: 30340115 DOI: 10.1016/j.ijfoodmicro.2018.10.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/20/2018] [Accepted: 10/10/2018] [Indexed: 11/19/2022]
Abstract
The ultraviolet-C (UV-C) decimal reduction energy (DUV-C) values of 17 spoilage yeasts and their composited inoculum were determined in coconut liquid endosperm (pH 5.26, 5.8 °Brix, 0.04% malic acid, 0.17% w/v insoluble solids). Growth kinetic parameters of all the test yeast strains were first established to standardize the growth stage of the cells prior to inactivation studies. Approximately 4.0 to 5.0 log CFU/mL cells in the mid-stationary growth phase (30.3 to 39.9 h, 25 °C) were suspended in 4 mL turbulent flowing juice and subjected to UV-C irradiation at a surface irradiance range of 3.42 to 4.99 mW/cm2. Survivor populations after exposure to predetermined UV-C energy were enumerated, and were used to derive the DUV-C values using the linear regression and Baranyi and Roberts (1994) model fitting. Results show that the yeast strains exhibited either log-linear or biphasic inactivation behavior with inactivation lag. The most UV-C resistant spoilage yeast was found to be Cryptococcus albidus (LJY1) with DUV-C values of 122.72 and 214.89 mJ/cm2 determined from linear regression and model-fitting, respectively. The least UV-C resistant was Torulaspora delbrueckii (LYJ5) with a DUV-C of 17.34 (linear regression) and 17.35 mJ/cm2 (model-fitting). The DUV-C values determined from the model fitting were generally greater than those calculated from linear regression, although only those determined for C. albidus were significantly different. To the investigators' knowledge, this is the first report of the UV-C inactivation kinetic parameters of Kluyveromyces marxianus, Trichosporon cutaneum, Pichia anomala, and Meyerozyma guilliermondii and C. albidus in coconut liquid endosperm. The results of this study can be used in the establishment and validation of UV-C process schedules for coconut liquid endosperm and other similar commodities.
Collapse
Affiliation(s)
- Rodney J Feliciano
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, College of Home Economics, Alonso Hall, A. Ma. Regidor Street, University of the Philippines Diliman, 1101 Quezon City, Philippines
| | - Emil Emmanuel C Estilo
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, College of Home Economics, Alonso Hall, A. Ma. Regidor Street, University of the Philippines Diliman, 1101 Quezon City, Philippines
| | - Hiroyuki Nakano
- Laboratory of Food Microbiology and Hygiene, Department of Biofunctional Science and Technology, Graduate School of Biosphere Science, Hiroshima University, 1-4-4, Kagamiyama, Higashihiroshima 739-8528, Japan
| | - Alonzo A Gabriel
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Nutrition, College of Home Economics, Alonso Hall, A. Ma. Regidor Street, University of the Philippines Diliman, 1101 Quezon City, Philippines.
| |
Collapse
|
29
|
Ramaswamy HS, Xu M, Vatankhah H. Investigating the influence of pH and selected heating media on thermal destruction kinetics of Geobacillus stearothermophilus (ATCC10149). Food Measure 2019; 13:1310-22. [DOI: 10.1007/s11694-019-00046-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
30
|
Bydałek F, Myszograj S. Safe surface concept in vertical flow constructed wetland design to mitigate infection hazard. J Environ Sci Health A Tox Hazard Subst Environ Eng 2019; 54:246-255. [PMID: 30633653 DOI: 10.1080/10934529.2018.1546497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/31/2018] [Accepted: 11/04/2018] [Indexed: 06/09/2023]
Abstract
Decentralized wastewater management based on vertical flow constructed wetlands (VFCWs) can be an effective solution for minimizing sanitation problems also in urban landscapes, especially when considering rapidly expanding cities in developing countries. Yet, the mass implementation of VFCWs in urbanized areas first needs improvement of a few design drawbacks - among them, the control of infection hazard is of primary importance. Therefore, in this study, the possibility of mitigation of the VFCW-derived infection hazard was assessed, through analysis of bacteriostatic properties of top filtration layer materials, according to clinical experiences based on "safe" antimicrobial surfaces. The experiment was carried out on a daily operating VFCW. Coliform bacteria survival rates were measured for known VFCW construction materials such as Pinus bark, gravel, slag, charcoal and LECA. The calculated die-off rates expressed as 12-h first-order inactivation coefficients ranged between 6.91 h-1 (slag/summer) and 0.58 h-1 (Pinus bark/autumn). The obtained die-off curves showed charcoal, Pinus bark and LECA to have little bacteriostatic properties - even occasionally providing conditions promoting the growth of the coliform population. Meanwhile, slag and gravel were strictly inhibiting bacteria growth, reducing the population up to 99% within the first 3 h of contact time. The research showed that it is possible to significantly mitigate the infection hazard of VFCW by means of proper top-layer substrate material, similar or equal to slag or gravel.
Collapse
Affiliation(s)
| | - S Myszograj
- b Institute of Environmental Engineering , University of Zielona Góra , Zielona Góra , Poland
| |
Collapse
|
31
|
Aspridou Z, Balomenos A, Tsakanikas P, Manolakos E, Koutsoumanis K. Heterogeneity of single cell inactivation: Assessment of the individual cell time to death and implications in population behavior. Food Microbiol 2019; 80:85-92. [PMID: 30704600 DOI: 10.1016/j.fm.2018.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 11/01/2018] [Accepted: 12/21/2018] [Indexed: 11/22/2022]
Abstract
A direct microscopic time-lapse method, using appropriate staining for cell viability in a confocal scanning laser microscope, was used for the direct assessment of Salmonella Agona individual cell inactivation in small two-dimensional colonies exposed to osmotic stress. Individual cell inactivation times were fitted to a variety of continuous distributions using @Risk software. The best fitted distribution (LogLogistic) was further used to predict the inactivation of Salmonella populations of various initial levels using Monte Carlo simulation. The simulation results showed that the variability in inactivation kinetics is negligible for concentrations down to 100 cells and the population behavior can be described with a deterministic model. As the concentration decreases below 100 cells, however, the variability increases significantly indicating that the traditional D-value used in deterministic first order kinetic models is not valid. At a second stage, single cell behavior was monitored in larger three dimensional colonies. The results showed that colony size can affect the inactivation pattern. The effect of colony size on microbial inactivation was confirmed with validation experiments which showed a higher inactivation rate for populations consisting of single cells or small colonies compared to those consisting of cells organized in larger colonies.
Collapse
|
32
|
Jiang Y, Dennehy C, Lawlor PG, Hu Z, Yang Q, McCarthy G, Tan SP, Zhan X, Gardiner GE. Inactivation of Salmonella during dry co-digestion of food waste and pig manure. Waste Manag 2018; 82:231-240. [PMID: 30509585 DOI: 10.1016/j.wasman.2018.10.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/21/2018] [Accepted: 10/22/2018] [Indexed: 06/09/2023]
Abstract
Extremely high volatile fatty acids (VFAs) and ammonia concentrations can accumulate during dry co-digestion of organic wastes, which may inactivate pathogenic microorganisms. In this study, inactivation of Salmonella during dry co-digestion of pig manure (PM) and food waste (FW), which are both reservoirs of zoonotic pathogens, was examined. The effects of pH, VFAs, ammonia and their interactions were assessed on three inoculated Salmonella serotypes. The results show that dry co-digestion significantly decreased the Salmonella inactivation time from several months (in wet digestion) to as short as 6-7 days. A modified Weibull distribution was proposed to simulate Salmonella reduction and to calculate or predict the minimum inhibitory concentrations (MIC) of VFAs and ammonia. Statistical analysis showed that all the factors (pH, VFA type, VFA/ammonia concentration and Salmonella serotype) significantly impacted Salmonella inactivation (P < 0.01). The inhibitory effect sequence was pH > VFA concentration > VFA type > Salmonella serotype in VFA MIC tests, and ammonia concentration > pH > Salmonella serotype in ammonia MIC tests. The toxicity of VFAs was much greater than that of ammonia, and an antagonistic effect was found between VFAs and ammonia on Salmonella inactivation. Apart from the toxicity of free VFAs and free ammonia, the inhibitory effects of pH alone, ionized VFAs and ammonium were also observed.
Collapse
Affiliation(s)
- Yan Jiang
- Civil Engineering, College of Engineering & Informatics, National University of Ireland, Galway, Ireland
| | - Conor Dennehy
- Civil Engineering, College of Engineering & Informatics, National University of Ireland, Galway, Ireland
| | - Peadar G Lawlor
- Teagasc, Pig Development Department, Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland
| | - Zhenhu Hu
- School of Civil Engineering, Hefei University of Technology, Hefei 230009, Anhui Province, China
| | - Qingfeng Yang
- Civil Engineering, College of Engineering & Informatics, National University of Ireland, Galway, Ireland
| | - Gemma McCarthy
- Department of Science, Waterford Institute of Technology, Waterford, Ireland
| | - Shiau Pin Tan
- Department of Science, Waterford Institute of Technology, Waterford, Ireland
| | - Xinmin Zhan
- Civil Engineering, College of Engineering & Informatics, National University of Ireland, Galway, Ireland; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, China.
| | - Gillian E Gardiner
- Department of Science, Waterford Institute of Technology, Waterford, Ireland
| |
Collapse
|
33
|
Enger KS, Mitchell J, Murali B, Birdsell DN, Keim P, Gurian PL, Wagner DM. Evaluating the long-term persistence of Bacillus spores on common surfaces. Microb Biotechnol 2018; 11:1048-1059. [PMID: 29726106 PMCID: PMC6196380 DOI: 10.1111/1751-7915.13267] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 02/16/2018] [Accepted: 03/10/2018] [Indexed: 11/27/2022] Open
Abstract
Bacillus spores resist inactivation, but the extent of their persistence on common surfaces is unclear. This work addresses knowledge gaps regarding biothreat agents in the environment to reduce uncertainty in risk assessment models. Studies were conducted to investigate the long-term inactivation of Bacillus anthracis and three commonly used surrogate organisms - B. cereus, B. atrophaeus and B. thuringiensis on three materials: laminate countertop, stainless steel and polystyrene Petri dishes. Viable spores were measured at 1, 30, 90, 196, 304 and 1038 days. Twelve different persistence models were fit to the data using maximum likelihood estimation and compared. The study found that (1) spore inactivation was not log-linear, as commonly modelled; (2) B. thuringiensis counts increased at 24 h on all materials, followed by a subsequent decline; (3) several experiments showed evidence of a 'U' shape, with spore counts apparently decreasing and then increasing between 1 and 304 days; (4) spores on polystyrene showed little inactivation; and (5) the maximum inactivation of 56% was observed for B. atrophaeus spores on steel at 196 days. Over the range of surfaces, time durations and conditions (humidity controlled vs. uncontrolled) examined, B. thuringiensis most closely matched the behaviour of B. anthracis.
Collapse
Affiliation(s)
- Kyle S. Enger
- Department of Biosystems & Agricultural EngineeringMichigan State UniversityEast LansingMIUSA
- Present address:
Medical Advantage GroupEast LansingMIUSA
| | - Jade Mitchell
- Department of Biosystems & Agricultural EngineeringMichigan State UniversityEast LansingMIUSA
| | - Bharathi Murali
- Department of Biosystems & Agricultural EngineeringMichigan State UniversityEast LansingMIUSA
| | - Dawn N. Birdsell
- Department of Biological SciencesNorthern Arizona UniversityFlagstaffAZUSA
| | - Paul Keim
- Department of Biological SciencesNorthern Arizona UniversityFlagstaffAZUSA
| | - Patrick L. Gurian
- Department of Civil, Architectural, and Environmental EngineeringDrexel UniversityPhiladelphiaPAUSA
| | - David M. Wagner
- Department of Biological SciencesNorthern Arizona UniversityFlagstaffAZUSA
| |
Collapse
|
34
|
Koyama K, Abe H, Kawamura S, Koseki S. Stochastic simulation for death probability of bacterial population considering variability in individual cell inactivation time and initial number of cells. Int J Food Microbiol 2018; 290:125-131. [PMID: 30326383 DOI: 10.1016/j.ijfoodmicro.2018.10.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 08/30/2018] [Accepted: 10/05/2018] [Indexed: 11/24/2022]
Abstract
Decimal reduction time (D-value) based on the first-order survival kinetics model is not sufficient for reliable estimation of the bacterial survivors of inactivation treatment because the model does not consider inactivation curvature. However, even though doubt exists in the calculation of D-value, it is still widely used for risk assessment and sterilisation time estimation. This paper proposes an approach for estimating the time-to-inactivation and death probability of bacterial population that considers individual cell heterogeneity and initial number of cells via computer simulation. In the proposed approach, Weibull and Poisson distributions are respectively used to provide individual cell inactivation time variability and initial number of cells variability. Our simulation results show that the time-to-inactivation significantly depends on kinetics curvature and initial number of cells. For example, with increases in the initial number of cells, the respective variance of the time-to-inactivation of log-linear, concave downward curve, and concave upward curve remains constant, decreases, and increases, respectively. The death probability contour plot was successfully generated via our computer simulation approach without using D-value estimation. Further, the death probability calculated using our stochastic approach was virtually the same as that obtained using inactivation kinetics. We validated the simulation by using literature data for acid inactivation of Salmonella population. The results of this study indicate that inactivation curvature can replace D-value extrapolation to estimate the death probability of bacterial population. Further, our computer simulation facilitates realistic estimation of the time-to-inactivation of bacterial population. The R code used for the above stochastic calculation is outlined.
Collapse
Affiliation(s)
- Kento Koyama
- Graduate School of Agricultural Science, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Hiroki Abe
- Graduate School of Agricultural Science, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Shuso Kawamura
- Graduate School of Agricultural Science, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Shigenobu Koseki
- Graduate School of Agricultural Science, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan.
| |
Collapse
|
35
|
Falardeau J, Walji K, Haure M, Fong K, Taylor G, Ma Y, Smukler S, Wang S. Native bacterial communities and Listeria monocytogenes survival in soils collected from the Lower Mainland of British Columbia, Canada. Can J Microbiol 2018; 64:695-705. [PMID: 29775543 DOI: 10.1139/cjm-2018-0115] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Soil is an important reservoir for Listeria monocytogenes, a foodborne pathogen implicated in numerous produce-related outbreaks. Our objectives were to (i) compare the survival of L. monocytogenes among three soils, (ii) compare the native bacterial communities across these soils, and (iii) investigate relationships between L. monocytogenes survival, native bacterial communities, and soil properties. Listeria spp. populations were monitored on PALCAM agar in three soils inoculated with L. monocytogenes (∼5 × 106 CFU/g): conventionally farmed (CS), grassland transitioning to conventionally farmed (TS), and uncultivated grassland (GS). Bacterial diversity of the soils was analyzed using 16S rRNA targeted amplicon sequencing. A 2 log reduction of Listeria spp. was observed in all soils within 10 days, but at a significantly lower rate in GS (Fisher's least significant difference test; p < 0.05). Survival correlated with increased moisture and a neutral pH. GS showed the highest microbial diversity. Acidobacteria was the dominant phylum differentiating CS and TS from GS, and was negatively correlated with pH, carbon, nitrogen, and moisture. High moisture content and neutral pH are likely to increase the ability of L. monocytogenes to persist in soil. This study confirmed that native bacterial communities and short-term survival of L. monocytogenes varies across soils.
Collapse
Affiliation(s)
- Justin Falardeau
- a Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Khalil Walji
- b Applied Biology and Soil Science, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Maxime Haure
- c Agri-food engineering, Agrosup Dijon, 21000 Dijon, France
| | - Karen Fong
- a Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Greg Taylor
- d British Columbia Genome Sciences Centre, Vancouver, BC V5Z 4S6, Canada
| | - Yussanne Ma
- d British Columbia Genome Sciences Centre, Vancouver, BC V5Z 4S6, Canada
| | - Sean Smukler
- b Applied Biology and Soil Science, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Siyun Wang
- a Food, Nutrition and Health, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| |
Collapse
|
36
|
Lopes RP, Mota MJ, Gomes AM, Delgadillo I, Saraiva JA. Application of High Pressure with Homogenization, Temperature, Carbon Dioxide, and Cold Plasma for the Inactivation of Bacterial Spores: A Review. Compr Rev Food Sci Food Saf 2018; 17:532-555. [PMID: 33350128 DOI: 10.1111/1541-4337.12311] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 08/29/2017] [Accepted: 09/01/2017] [Indexed: 12/18/2022]
Abstract
Formation of highly resistant spores is a concern for the safety of low-acid foods as they are a perfect vehicle for food spoilage and/or human infection. For spore inactivation, the strategy usually applied in the food industry is the intensification of traditional preservation methods to sterilization levels, which is often accompanied by decreases of nutritional and sensory properties. In order to overcome these unwanted side effects in food products, novel and emerging sterilization technologies are being developed, such as pressure-assisted thermal sterilization, high-pressure carbon dioxide, high-pressure homogenization, and cold plasma. In this review, the application of these emergent technologies is discussed, in order to understand the effects on bacterial spores and their inactivation and thus ensure food safety of low-acid foods. In general, the application of these novel technologies for inactivating spores is showing promising results. However, it is important to note that each technique has specific features that can be more suitable for a particular type of product. Thus, the most appropriate sterilization method for each product (and target microorganisms) should be assessed and carefully selected.
Collapse
Affiliation(s)
- Rita P Lopes
- QOPNA, Chemistry Dept., Univ. of Aveiro, Campus Univ. de Santiago, 3810-193 Aveiro, Portugal
| | - Maria J Mota
- QOPNA, Chemistry Dept., Univ. of Aveiro, Campus Univ. de Santiago, 3810-193 Aveiro, Portugal
| | - Ana M Gomes
- Escola Superior de Biotecnologia, Univ. Católica Portuguesa, 4200-072 Porto, Portugal
| | - Ivonne Delgadillo
- QOPNA, Chemistry Dept., Univ. of Aveiro, Campus Univ. de Santiago, 3810-193 Aveiro, Portugal
| | - Jorge A Saraiva
- QOPNA, Chemistry Dept., Univ. of Aveiro, Campus Univ. de Santiago, 3810-193 Aveiro, Portugal
| |
Collapse
|
37
|
Ai J, Witt T, Gidley MJ, Turner MS, Stokes JR, Bonilla MR. Modelling of Thermal Sterilisation of High-Moisture Snack Foods: Feasibility Analysis and Optimization. FOOD BIOPROCESS TECH 2018. [DOI: 10.1007/s11947-018-2075-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
38
|
Dolan HL, Bastarrachea LJ, Tikekar RV. Inactivation of Listeria innocua by a combined treatment of low-frequency ultrasound and zinc oxide. Lebensm Wiss Technol 2018; 88:146-51. [DOI: 10.1016/j.lwt.2017.10.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
39
|
Abstract
The conservation of microorganisms is essential for their in-depth study. However, today's most widely used conservation methods, based on the use of distilled water, soil, oils, or silica, do not guarantee the stability of fungal cells, especially dermatophytes. This problem led us to evaluate the conservation capacity of a cryogenic vials system containing glass beads covered in a cryopreservant hypertonic solution as an alternative method of storage of fungal cells at -80°C. Up to 570 strains of fungi belonging to 27 different species, isolated from clinical samples, were inoculated into cryotubes containing 25 glass beads covered in a cryopreserving hypertonic solution. Suspensions were mixed vigorously and the cryopreserving solution was discarded. The tubes were frozen at -80°C for a period of 42 months and periodically, a glass bead was removed from each cryotube and inoculated onto Sabouraud dextrose agar, and incubated at 30°C for 7-14 days to evaluate the number of colonies recovered, their purity, and phenotypic characteristics. All yeast isolates were recovered, unlike 2 isolates (4.4%) of the mold group and 21 (10.7%) of the dermatophytes. Survival rates were close to 100% for yeasts and molds, with expiration times being estimated for almost indefinite stocks, and 62% for dermatophytes, with an average expiration date of 25.5 years. The phenotypic characteristics remained comparable to those of the strains before storage. Conservation at -80°C using cryogenic vials is a reliable and efficient system for the conservation of fungal collections, and although the behavior differs by groups, stratified survival data are obtained to avoid extinction.
Collapse
Affiliation(s)
- Jesús García-Martínez
- 1 Department of Microbiology, Hospital Universitario de Fuenlabrada , Fuenlabrada, Spain .,2 Laboratory Medicine Department, University Hospital of Fuenlabrada , Fuenlabrada, Spain .,3 Hospital Universitario de Fuenlabrada , Fuenlabrada Biobank, Spain
| | - Daniel López Lacomba
- 2 Laboratory Medicine Department, University Hospital of Fuenlabrada , Fuenlabrada, Spain .,3 Hospital Universitario de Fuenlabrada , Fuenlabrada Biobank, Spain
| | | |
Collapse
|
40
|
Wang Y, Wang Y, Wang Y, Murray CK, Hamblin MR, Hooper DC, Dai T. Antimicrobial blue light inactivation of pathogenic microbes: State of the art. Drug Resist Updat 2017; 33-35:1-22. [PMID: 29145971 DOI: 10.1016/j.drup.2017.10.002] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/28/2017] [Accepted: 10/02/2017] [Indexed: 12/20/2022]
Abstract
As an innovative non-antibiotic approach, antimicrobial blue light in the spectrum of 400-470nm has demonstrated its intrinsic antimicrobial properties resulting from the presence of endogenous photosensitizing chromophores in pathogenic microbes and, subsequently, its promise as a counteracter of antibiotic resistance. Since we published our last review of antimicrobial blue light in 2012, there have been a substantial number of new studies reported in this area. Here we provide an updated overview of the findings from the new studies over the past 5 years, including the efficacy of antimicrobial blue light inactivation of different microbes, its mechanism of action, synergism of antimicrobial blue light with other angents, its effect on host cells and tissues, the potential development of resistance to antimicrobial blue light by microbes, and a novel interstitial delivery approach of antimicrobial blue light. The potential new applications of antimicrobial blue light are also discussed.
Collapse
Affiliation(s)
- Yucheng Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Cancer Center, Aviation General Hospital, Beijing, China; Department of Medical Oncology, Beijing Institute of Translational Medicine, Chinese Academy of Sciences, Beijing, China
| | - Ying Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Laser Medicine, Chinese PLA General Hospital, Beijing, China
| | - Yuguang Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Center of Digital Dentistry, School and Hospital of Stomatology, Peking University, Beijing, China
| | - Clinton K Murray
- Infectious Disease Service, San Antonio Military Medical Center, JBSA-Fort Sam Houston, TX, USA
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - David C Hooper
- Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Tianhong Dai
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
41
|
|
42
|
Chase JA, Atwill ER, Partyka ML, Bond RF, Oryang D. Inactivation of Escherichia coli O157:H7 on Romaine Lettuce When Inoculated in a Fecal Slurry Matrix. J Food Prot 2017; 80:792-798. [PMID: 28371591 DOI: 10.4315/0362-028x.jfp-16-307] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 12/12/2016] [Indexed: 11/11/2022]
Abstract
A field trial was conducted in July 2011 to quantify the inactivation rate of Escherichia coli O157:H7 when mixed with fecal slurry and applied to romaine lettuce leaves. Lettuce was grown under commercial conditions in Salinas Valley, CA. One-half milliliter of rabbit fecal slurry, containing 6.3 × 107 CFU of E. coli O157:H7, was inoculated onto the upper (adaxial) surface of a lower leaf on 240 heads of lettuce within 30 min after a 2.5-h irrigation event. Forty-eight romaine lettuce heads were collected per event at 2.5 h (day 0.1), 19.75 h (day 0.8), 43.25 h (day 1.8), 67.25 h (day 2.8), and 91.75 h (day 3.8) postinoculation and were analyzed for the concentration of E. coli O157:H7 (Ct). E. coli O157:H7 was detected on 100% of collected heads in concentrations ranging from 340 to 3.40 × 1010 most probable number (MPN) per head. Enumeration data indicate substantial growth of E. coli O157:H7 postinoculation (2.5 h), leading to elevated concentrations, 1 to 3 log above the starting inoculum concentration (Co). By the end of the 92-h trial, we observed a net 0.8-log mean reduction of E. coli O157:H7 compared with Co; however, after accounting for the substantial bacterial growth, there was an overall 2.3-log reduction by the final sampling event (92 h). On the basis of two different regression models that used either the raw data for Ct or log-transformed values of Ct/Co during the period 2.5 to 91.75 h postinoculation, there was an estimated 76 to 80% reduction per day in bacterial counts; however, more accurate predictions of MPN per head of lettuce were generated by using non-log-transformed values of Ct. This study provides insight into the survival of E. coli O157:H7 transferred via splash from a contaminated fecal source onto produce during irrigation. Moreover, these findings can help generate inactivation times following a potential contamination incident.
Collapse
Affiliation(s)
- Jennifer A Chase
- Western Center for Food Safety, University of California, Davis, 1477 Drew Avenue, Suite 101, Davis, California 95618
| | - Edward R Atwill
- Western Center for Food Safety, University of California, Davis, 1477 Drew Avenue, Suite 101, Davis, California 95618
| | - Melissa L Partyka
- Western Center for Food Safety, University of California, Davis, 1477 Drew Avenue, Suite 101, Davis, California 95618
| | - Ronald F Bond
- Western Center for Food Safety, University of California, Davis, 1477 Drew Avenue, Suite 101, Davis, California 95618
| | - David Oryang
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, 5100 Paint Branch Parkway, College Park, Maryland 20740, USA
| |
Collapse
|
43
|
Padervand M, Karanji AK, Elahifard MR. Copper, gold, and silver decorated magnetic core–polymeric shell nanostructures for destruction of pathogenic bacteria. Russ J Phys Chem 2017. [DOI: 10.1134/s0036024417050028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
44
|
Tremarin A, Brandão TR, Silva CL. Inactivation kinetics of Alicyclobacillus acidoterrestris in apple juice submitted to ultraviolet radiation. Food Control 2017; 73:18-23. [DOI: 10.1016/j.foodcont.2016.07.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
45
|
He X, Liu P, Zheng G, Chen H, Shi W, Cui Y, Ren H, Zhang XX. Evaluation of five microbial and four mitochondrial DNA markers for tracking human and pig fecal pollution in freshwater. Sci Rep 2016; 6:35311. [PMID: 27734941 PMCID: PMC5062121 DOI: 10.1038/srep35311] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 09/27/2016] [Indexed: 12/16/2022] Open
Abstract
This study systematically evaluated five microbial and four mitochondrial DNA (mtDNA) markers, including sensitivities and specificities under PCR method, and fecal concentrations and decay rates in water under qPCR method. The microbial DNA markers were the three human-associated (BacH, HF183 and B.adolescentis) and two pig-associated (Pig-2-Bac and L.amylovorus), while the mtDNA ones were two human- (H-ND6 and H-ND5) and two pig-associated (P-CytB and P-ND5). All the mtDNA markers showed higher sensitivity (100%) than the microbial ones (84.0-88.8%) except Pig-2-Bac (100%). Specificities of the human mtDNA markers (99.1 and 98.1%) were higher than those of the human-associated microbial ones (57.0-88.8%). But this pattern was not observed in the pig-associated markers where Pig-2-Bac had 100% specificity. The reliability of H-ND6 and H-ND5 was further evidenced to identify locations of the most polluted within the Taihu Lake watershed of China. In general, the microbial DNA markers demonstrated a higher fecal concentration than the mtDNA ones; increasing temperature and sunlight exposure accelerated significantly the decay of all the DNA markers. Results of this study suggest that DNA markers H-ND6, H-ND5, and Pig-2-Bac may be among the best for fecal source tracking in water.
Collapse
Affiliation(s)
- Xiwei He
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| | - Peng Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| | - Guolu Zheng
- College of Agriculture, Environmental and Human Sciences, Lincoln University, Missouri, USA
| | - Huimei Chen
- Jiangsu Key Laboratory of Molecular Medicine, School of Medicine, Nanjing University, China
| | - Wei Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| | - Yibin Cui
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| | - Xu-Xiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, China
| |
Collapse
|
46
|
Rachon G, Peñaloza W, Gibbs PA. Inactivation of Salmonella, Listeria monocytogenes and Enterococcus faecium NRRL B-2354 in a selection of low moisture foods. Int J Food Microbiol 2016; 231:16-25. [DOI: 10.1016/j.ijfoodmicro.2016.04.022] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 04/12/2016] [Accepted: 04/16/2016] [Indexed: 11/21/2022]
|
47
|
Lisle JT. Natural inactivation of Escherichia coli in anaerobic and reduced groundwater. J Appl Microbiol 2016; 120:1739-50. [PMID: 26972559 DOI: 10.1111/jam.13126] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/03/2016] [Accepted: 03/06/2016] [Indexed: 11/28/2022]
Abstract
AIMS Inactivation rates of Escherichia coli in groundwater have most often been determined in aerobic and oxidized systems. This study examined E. coli inactivation rates in anaerobic and extremely reduced groundwater systems that have been identified as recharge zones. METHODS AND RESULTS Groundwater from six artesian wells was diverted to above-ground, flow-through mesocosms that contained laboratory grown E. coli in diffusion chambers. All groundwater was anaerobic and extremely reduced (ORP < -300 mV). Cells were plated onto mTEC agar during 21-day incubation periods. All data fit a bi-phasic inactivation model, with >95% of the E. coli population being inactivated <11·0 h (mean k = 0·488 ±0·188 h(-1) ). CONCLUSIONS The groundwater geochemical conditions enhanced the inactivation of E. coli to rates approx. 21-fold greater than previously published inactivation rate in groundwater (mean k = 0·023 ± 0·030 h(-1) ). Also, mTEC agar inhibits E. coli growth following exposure to anaerobic and reduced groundwater. SIGNIFICANCE AND IMPACT OF THE STUDY Aquifer recharge zones with geochemical characteristics observed in this study complement above-ground engineered processes (e.g. filtration, disinfection), while increasing the overall indicator micro-organism log-reduction rate of a facility.
Collapse
Affiliation(s)
- J T Lisle
- US Geological Survey, St. Petersburg Coastal & Marine Science Center, St. Petersburg, FL, USA
| |
Collapse
|
48
|
Desneux J, Biscuit A, Picard S, Pourcher AM. Fate of Viable but Non-culturable Listeria monocytogenes in Pig Manure Microcosms. Front Microbiol 2016; 7:245. [PMID: 26973623 PMCID: PMC4773784 DOI: 10.3389/fmicb.2016.00245] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/15/2016] [Indexed: 11/15/2022] Open
Abstract
The fate of two strains of Listeria monocytogenes and their ability to become viable but non-culturable (VBNC) was investigated in microcosms containing piggery effluents (two raw manures and two biologically treated manures) stored for 2 months at 8 and 20°C. Levels of L. monocytogenes were estimated using the culture method, qPCR, and propidium monoazide treatment combined with qPCR (qPCRPMA). The chemical composition and the microbial community structure of the manures were also analyzed. The strains showed similar decline rates and persisted up to 63 days. At day zero, the percentage of VBNC cells among viable cells was higher in raw manures (81.5-94.8%) than in treated manures (67.8-79.2%). The changes in their proportion over time depended on the temperature and on the type of effluent: the biggest increase was observed in treated manures at 20°C and the smallest increase in raw manures at 8°C. The chemical parameters had no influence on the behavior of the strains, but decrease of the persistence of viable cells was associated with an increase in the microbial richness of the manures. This study demonstrated that storing manure altered the culturability of L. monocytogenes, which rapidly entered the VBNC state, and underlines the importance of including VBNC cells when estimating the persistence of the pathogens in farm effluents.
Collapse
Affiliation(s)
- Jérémy Desneux
- Irstea-RennesRennes, France
- Université Européenne de BretagneRennes, France
| | - Audrey Biscuit
- Irstea-RennesRennes, France
- Université Européenne de BretagneRennes, France
| | - Sylvie Picard
- Irstea-RennesRennes, France
- Université Européenne de BretagneRennes, France
| | | |
Collapse
|
49
|
Zhang Y, Zhu Y, Chen J, Wang Y, Sherwood ME, Murray CK, Vrahas MS, Hooper DC, Hamblin MR, Dai T. Antimicrobial blue light inactivation of Candida albicans: In vitro and in vivo studies. Virulence 2016; 7:536-45. [PMID: 26909654 DOI: 10.1080/21505594.2016.1155015] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Fungal infections are a common cause of morbidity, mortality and cost in critical care populations. The increasing emergence of antimicrobial resistance necessitates the development of new therapeutic approaches for fungal infections. In the present study, we investigated the effectiveness of an innovative approach, antimicrobial blue light (aBL), for inactivation of Candida albicans in vitro and in infected mouse burns. A bioluminescent strain of C. albicans was used. The susceptibilities to aBL (415 nm) were compared between C. albicans and human keratinocytes. The potential development of aBL resistance by C. albicans was investigated via 10 serial passages of C. albicans on aBL exposure. For the animal study, a mouse model of thermal burn infected with the bioluminescent C. albicans strain was used. aBL was delivered to mouse burns approximately 12 h after fungal inoculation. Bioluminescence imaging was performed to monitor in real time the extent of infection in mice. The results obtained from the studies demonstrated that C. albicans was approximately 42-fold more susceptible to aBL than human keratinocytes. Serial passaging of C. albicans on aBL exposure implied a tendency of reduced aBL susceptibility of C. albicans with increasing numbers of passages; however, no statistically significant difference was observed in the post-aBL survival rate of C. albicans between the first and the last passage (P>0.05). A single exposure of 432 J/cm(2) aBL reduced the fungal burden in infected mouse burns by 1.75-log10 (P=0.015). Taken together, our findings suggest aBL is a potential therapeutic for C. albicans infections.
Collapse
Affiliation(s)
- Yunsong Zhang
- a Department of Plastic Surgery and Cosmetic , The Second People's Hospital of Guangdong Province , Guangzhou , China.,b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA
| | - Yingbo Zhu
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,d School of Medicine, Tongji University , Shanghai , China
| | - Jia Chen
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,e Shanghai Dermatology Hospital , Shanghai , China
| | - Yucheng Wang
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,f Department of Laser Medicine , Chinese PLA General Hospital , Beijing , China
| | - Margaret E Sherwood
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA
| | - Clinton K Murray
- g Infectious Disease Service, Brooke Army Medical Center, Fort Sam Houston , TX , USA
| | - Mark S Vrahas
- h Department of orthopedic Surgery , Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA
| | - David C Hooper
- i Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA
| | - Michael R Hamblin
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,j Harvard-MIT Division of Health Sciences and Technology , Cambridge , MA , USA
| | - Tianhong Dai
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA
| |
Collapse
|
50
|
Bevilacqua A, Speranza B, Sinigaglia M, Corbo MR. A Focus on the Death Kinetics in Predictive Microbiology: Benefits and Limits of the Most Important Models and Some Tools Dealing with Their Application in Foods. Foods 2015; 4:565-580. [PMID: 28231222 PMCID: PMC5224560 DOI: 10.3390/foods4040565] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/29/2015] [Accepted: 10/06/2015] [Indexed: 11/17/2022] Open
Abstract
Predictive Microbiology (PM) deals with the mathematical modeling of microorganisms in foods for different applications (challenge test, evaluation of microbiological shelf life, prediction of the microbiological hazards connected with foods, etc.). An interesting and important part of PM focuses on the use of primary functions to fit data of death kinetics of spoilage, pathogenic, and useful microorganisms following thermal or non-conventional treatments and can also be used to model survivors throughout storage. The main topic of this review is a focus on the most important death models (negative Gompertz, log-linear, shoulder/tail, Weibull, Weibull+tail, re-parameterized Weibull, biphasic approach, etc.) to pinpoint the benefits and the limits of each model; in addition, the last section addresses the most important tools for the use of death kinetics and predictive microbiology in a user-friendly way.
Collapse
Affiliation(s)
- Antonio Bevilacqua
- Department of the Science of Agriculture, Food and Environment, University of Foggia, Via Napoli 25, 71122 Foggia, Italy.
| | - Barbara Speranza
- Department of the Science of Agriculture, Food and Environment, University of Foggia, Via Napoli 25, 71122 Foggia, Italy.
| | - Milena Sinigaglia
- Department of the Science of Agriculture, Food and Environment, University of Foggia, Via Napoli 25, 71122 Foggia, Italy.
| | - Maria Rosaria Corbo
- Department of the Science of Agriculture, Food and Environment, University of Foggia, Via Napoli 25, 71122 Foggia, Italy.
| |
Collapse
|