1
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Wang D, Chen Q, Hui B, Yuan K, Zou X, Ma N, Gong Z, Fan M. Microwave disinfection strengthened by a biochar-based microwave absorbing material for sewage resource utilization. ENVIRONMENTAL TECHNOLOGY 2023:1-9. [PMID: 37610014 DOI: 10.1080/09593330.2023.2251656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 08/05/2023] [Indexed: 08/24/2023]
Abstract
Proper disinfection treatment is the basic guarantee for safe utilisation of sewage. However, the commonly used disinfection methods are not suitable for nutrients containing reclaimed water. In this work, the microwave disinfection method assisted by a microwave-absorbing material in recycled water samples was investigated. Magnetic corn stalk biochar (MCSB), the microwave absorbing material, was prepared by high temperature carbonisation of corn stalk particles impregnated with ferrous sulfate. Escherichia coli and fecal coliforms were selected as target microorganisms to investigate the disinfection efficiency of MCSB assisted microwave radiation (MW/MCSB). The addition of microwave absorbing materials significantly improves the disinfection effect of water samples. Compared with the microwave radiation (MW) without MCSB, the bactericidal rate by using 107 CFU/L E. coli suspension increased from 63.5% to 100% at 480 W for 30 s after adding 4 g/L MCSB. Besides, the effects of MCSB dosage, microwave power, microwave radiation time, and initial bacterial concentration on disinfection efficiency were explored. Moreover, the bactericidal efficiency for actual sewage samples was also demonstrated by treating the effluent from septic tank sewage. The residual fecal coliforms in treated water samples met China's farmland irrigation water standard (GB 5084-2021). The result indicates that the proposed method of microwave disinfection strengthened by MCSB has a promising application prospect for reclaimed water disinfection.
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Affiliation(s)
- Dongmei Wang
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
| | - Qianxi Chen
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
| | - Binyu Hui
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
| | - Kai Yuan
- Guangyuan City Development Group Co., Ltd, Guangyuan, People's Republic of China
| | - Xianbing Zou
- Guangyuan City Development Group Co., Ltd, Guangyuan, People's Republic of China
| | - Nan Ma
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
| | - Zhengjun Gong
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
| | - Meikun Fan
- Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu, People's Republic of China
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2
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Levels of Salmonella enterica and Listeria monocytogenes in Alternative Irrigation Water Vary Based on Water Source on the Eastern Shore of Maryland. Microbiol Spectr 2021; 9:e0066921. [PMID: 34612697 PMCID: PMC8510256 DOI: 10.1128/spectrum.00669-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Irrigation water sources have been shown to harbor foodborne pathogens and could contribute to the outbreak of foodborne illness related to consumption of contaminated produce. Determining the probability of and the degree to which these irrigation water sources contain these pathogens is paramount. The purpose of this study was to determine the prevalence of Salmonella enterica and Listeria monocytogenes in alternative irrigation water sources. Water samples (n = 188) were collected over 2 years (2016 to 2018) from 2 reclaimed water plants, 3 nontidal freshwater rivers, and 1 tidal brackish river on Maryland's Eastern Shore (ESM). Samples were collected by filtration using modified Moore swabs (MMS) and analyzed by culture methods. Pathogen levels were quantified using a modified most probable number (MPN) procedure with three different volumes (10 liters, 1 liter, and 0.1 liter). Overall, 65% (122/188) and 40% (76/188) of water samples were positive for S. enterica and L. monocytogenes, respectively. For both pathogens, MPN values ranged from 0.015 to 11 MPN/liter. Pathogen levels (MPN/liter) were significantly (P < 0.05) greater for the nontidal freshwater river sites and the tidal brackish river site than the reclaimed water sites. L. monocytogenes levels in water varied based on season. Detection of S. enterica was more likely with 10-liter filtration compared to 0.1-liter filtration. The physicochemical factors measured attributed only 6.4% of the constrained variance to the levels of both pathogens. This study shows clear variations in S. enterica and L. monocytogenes levels in irrigation water sources on ESM. IMPORTANCE In the last several decades, Maryland's Eastern Shore has seen significant declines in groundwater levels. While this area is not currently experiencing drought conditions or water scarcity, this research represents a proactive approach. Efforts, to investigate the levels of pathogenic bacteria and the microbial quality of alternative irrigation water are important for sustainable irrigation practices into the future. This research will be used to determine the suitability of alternative irrigation water sources for use in fresh produce irrigation to conserve groundwater.
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3
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Shearer AEH, Kniel KE. Foodborne Illness Outbreak Investigation for One Health Postsecondary Education. JOURNAL OF MICROBIOLOGY & BIOLOGY EDUCATION 2021; 22:jmbe00129-21. [PMID: 34594466 PMCID: PMC8442033 DOI: 10.1128/jmbe.00129-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 06/21/2021] [Indexed: 06/01/2023]
Abstract
One Health concepts were incorporated in a foodborne disease outbreak investigation with game features of data presented as visual and manipulative clues. Postsecondary pre-veterinary medicine and animal biosciences students and food science students (n = 319) enrolled in an introductory animal and food sciences course over a 3-year period received a brief introduction to foodborne illness, an outbreak scenario, and investigative tasks to complete individually or in groups. Tasks addressed epidemiology, laboratory, environment, traceback, recall, and prevention concepts. Gamification of the exercise involved generation of a numerical code to unlock a combination lock as an indication of successful organization, compilation, and interpretation of data. Students presented investigation findings and responses to critical thought questions on their roles. Student surveys on engagement and self-perceived change in conceptual understanding indicated that nearly all expressed increased understanding of outbreak investigations, safe food production, and environmental water as a transmission vehicle. Volunteered learned concepts indicated enhanced appreciation for the complexity of food safety and interdisciplinary connections. Students enjoyed the exercise (92%) and cited the clues and group interaction among the most enjoyable features. Objective assessment of student conceptual learning with the subset of students who conducted the investigation individually (n = 58) demonstrated significant increase in correct test responses (49% pretest; 76% posttest) after completion of the investigation for all questions combined and across all learning objectives. These data demonstrate the value of a foodborne disease investigation with escape room gamification features for engaging students in One Health concepts and exercising problem-solving, critical thinking, and skills for independent and collaborative work.
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Affiliation(s)
| | - Kalmia E. Kniel
- Department of Animal and Food Sciences, University of Delaware, Newark, Delaware, USA
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4
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Hernandez SM, Maurer JJ, Yabsley MJ, Peters VE, Presotto A, Murray MH, Curry S, Sanchez S, Gerner-Smidt P, Hise K, Huang J, Johnson K, Kwan T, Lipp EK. Free-Living Aquatic Turtles as Sentinels of Salmonella spp. for Water Bodies. Front Vet Sci 2021; 8:674973. [PMID: 34368271 PMCID: PMC8339271 DOI: 10.3389/fvets.2021.674973] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/25/2021] [Indexed: 11/13/2022] Open
Abstract
Reptile-associated human salmonellosis cases have increased recently in the United States. It is not uncommon to find healthy chelonians shedding Salmonella enterica. The rate and frequency of bacterial shedding are not fully understood, and most studies have focused on captive vs. free-living chelonians and often in relation to an outbreak. Their ecology and significance as sentinels are important to understanding Salmonella transmission. In 2012-2013, Salmonella prevalence was determined for free-living aquatic turtles in man-made ponds in Clarke and Oconee Counties, in northern Georgia (USA) and the correlation between species, basking ecology, demographics (age/sex), season, or landcover with prevalence was assessed. The genetic relatedness between turtle and archived, human isolates, as well as, other archived animal and water isolates reported from this study area was examined. Salmonella was isolated from 45 of 194 turtles (23.2%, range 14-100%) across six species. Prevalence was higher in juveniles (36%) than adults (20%), higher in females (33%) than males (18%), and higher in bottom-dwelling species (31%; common and loggerhead musk turtles, common snapping turtles) than basking species (15%; sliders, painted turtles). Salmonella prevalence decreased as forest cover, canopy cover, and distance from roads increased. Prevalence was also higher in low-density, residential areas that have 20-49% impervious surface. A total of 9 different serovars of two subspecies were isolated including 3 S. enterica subsp. arizonae and 44 S. enterica subsp. enterica (two turtles had two serotypes isolated from each). Among the S. enterica serovars, Montevideo (n = 13) and Rubislaw (n = 11) were predominant. Salmonella serovars Muenchen, Newport, Mississippi, Inverness, Brazil, and Paratyphi B. var L(+) tartrate positive (Java) were also isolated. Importantly, 85% of the turtle isolates matched pulsed-field gel electrophoresis patterns of human isolates, including those reported from Georgia. Collectively, these results suggest that turtles accumulate Salmonella present in water bodies, and they may be effective sentinels of environmental contamination. Ultimately, the Salmonella prevalence rates in wild aquatic turtles, especially those strains shared with humans, highlight a significant public health concern.
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Affiliation(s)
- Sonia M Hernandez
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States.,Department of Population Health, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - John J Maurer
- Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Michael J Yabsley
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States.,Department of Population Health, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Valerie E Peters
- Department of Biological Sciences, Eastern Kentucky University, Richmond, KY, United States
| | - Andrea Presotto
- Department of Geography, University of Georgia, Athens, GA, United States
| | - Maureen H Murray
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States.,Department of Population Health, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.,Davee Center for Epidemiology and Endocrinology and the Urban Wildlife Institute, Lincoln Park Zoo, Chicago, IL, United States
| | - Shannon Curry
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States.,Department of Population Health, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Susan Sanchez
- Athens Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Peter Gerner-Smidt
- Enteric Diseases Laboratory Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Kelley Hise
- Enteric Diseases Laboratory Branch, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Joyce Huang
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, United States.,Department of Population Health, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Kasey Johnson
- Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Tiffany Kwan
- Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Erin K Lipp
- Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, GA, United States
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5
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Summerlin HN, Pola CC, McLamore ES, Gentry T, Karthikeyan R, Gomes CL. Prevalence of Escherichia coli and Antibiotic-Resistant Bacteria During Fresh Produce Production (Romaine Lettuce) Using Municipal Wastewater Effluents. Front Microbiol 2021; 12:660047. [PMID: 34093474 PMCID: PMC8172605 DOI: 10.3389/fmicb.2021.660047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 04/21/2021] [Indexed: 11/13/2022] Open
Abstract
High demand for food and water encourages the exploration of new water reuse programs, including treated municipal wastewater usage. However, these sources could contain high contaminant levels posing risks to public health. The objective of this study was to grow and irrigate a leafy green (romaine lettuce) with treated wastewater from a municipal wastewater treatment plant to track Escherichia coli and antibiotic-resistant microorganisms through cultivation and post-harvest storage to assess their fate and prevalence. Contamination levels found in the foliage, leachate, and soil were directly (p < 0.05) related to E. coli concentrations in the irrigation water. Wastewater concentrations from 177 to 423 CFU ml-1 resulted in 15-25% retention in the foliage. Leachate and soil presented means of 231 and 116% retention, respectively. E. coli accumulation on the foliage was observed (p < 0.05) and increased by over 400% during 14-day storage (4°C). From randomly selected E. coli colonies, in all four biomass types, 81 and 34% showed resistance to ampicillin and cephalothin, respectively. Reclaimed wastewater usage for leafy greens cultivation could pose potential health risks, especially considering the bacteria found have a high probability of being antibiotic resistance. Successful reuse of wastewater in agriculture will depend on appropriate mitigation and management strategies to guarantee an inexpensive, efficient, and safe water supply.
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Affiliation(s)
- Harvey N Summerlin
- Department of Biological and Agricultural Engineering, Texas A&M University, College Station, TX, United States
| | - Cícero C Pola
- Department of Mechanical Engineering, Iowa State University, Ames, IA, United States
| | - Eric S McLamore
- Department of Agricultural Sciences, Clemson University, Clemson, SC, United States
| | - Terry Gentry
- Department of Soil and Crop Sciences, Texas A&M University, College Station, TX, United States
| | | | - Carmen L Gomes
- Department of Biological and Agricultural Engineering, Texas A&M University, College Station, TX, United States.,Department of Mechanical Engineering, Iowa State University, Ames, IA, United States
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6
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Ogunniyi AD, Dandie CE, Brunetti G, Drigo B, Aleer S, Hall B, Ferro S, Deo P, Venter H, Myers B, Donner E, Lombi E. Neutral electrolyzed oxidizing water is effective for pre-harvest decontamination of fresh produce. Food Microbiol 2021; 93:103610. [PMID: 32912583 DOI: 10.1016/j.fm.2020.103610] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 10/23/2022]
Abstract
Pre-harvest sanitization of irrigation water has potential for reducing pathogen contamination of fresh produce. We compared the sanitizing effects of irrigation water containing neutral electrolyzed oxidizing water (EOW) or sodium hypochlorite (NaClO) on pre-harvest lettuce and baby spinach leaves artificially contaminated with a mixture of Escherichia coli, Salmonella Enteritidis and Listeria innocua (~1 × 108 colony-forming units/mL each resuspended in water containing 100 mg/L dissolved organic carbon, simulating a splash-back scenario from contaminated soil/manure). The microbial load and leaf quality were assessed over 7 days, and post-harvest shelf life evaluated for 10 days. Irrigation with water containing EOW or NaClO at 50 mg/L free chlorine significantly reduced the inoculated bacterial load by ≥ 1.5 log10, whereas tap water irrigation reduced the inoculated bacterial load by an average of 0.5 log10, when compared with untreated leaves. There were no visual effects of EOW or tap water irrigation on baby spinach or lettuce leaf surfaces pre- or post-harvest, whereas there were obvious negative effects of NaClO irrigation on leaf appearance for both plants, including severe necrotic zones and yellowing/browning of leaves. Therefore, EOW could serve as a viable alternative to chemical-based sanitizers for pre-harvest disinfection of minimally processed vegetables.
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Affiliation(s)
- Abiodun D Ogunniyi
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia.
| | - Catherine E Dandie
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Gianluca Brunetti
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Barbara Drigo
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Samuel Aleer
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Barbara Hall
- Plant Health and Biosecurity, SARDI, Adelaide, South Australia, Australia
| | - Sergio Ferro
- Ecas4 Australia Pty Ltd, 8/1 London Road, Mile End South, South Australia, Australia
| | - Permal Deo
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Henrietta Venter
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Baden Myers
- Australian Flow Management Group & UniSA STEM, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Erica Donner
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Enzo Lombi
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
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7
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Sense–Analyze–Respond–Actuate (SARA) Paradigm: Proof of Concept System Spanning Nanoscale and Macroscale Actuation for Detection of Escherichia coli in Aqueous Media. ACTUATORS 2020. [DOI: 10.3390/act10010002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Foodborne pathogens are a major concern for public health. We demonstrate for the first time a partially automated sensing system for rapid (~17 min), label-free impedimetric detection of Escherichia coli spp. in food samples (vegetable broth) and hydroponic media (aeroponic lettuce system) based on temperature-responsive poly(N-isopropylacrylamide) (PNIPAAm) nanobrushes. This proof of concept (PoC) for the Sense-Analyze-Respond-Actuate (SARA) paradigm uses a biomimetic nanostructure that is analyzed and actuated with a smartphone. The bio-inspired soft material and sensing mechanism is inspired by binary symbiotic systems found in nature, where low concentrations of bacteria are captured from complex matrices by brush actuation driven by concentration gradients at the tissue surface. To mimic this natural actuation system, carbon-metal nanohybrid sensors were fabricated as the transducer layer, and coated with PNIPAAm nanobrushes. The most effective coating and actuation protocol for E. coli detection at various temperatures above/below the critical solution temperature of PNIPAAm was determined using a series of electrochemical experiments. After analyzing nanobrush actuation in stagnant media, we developed a flow through system using a series of pumps that are triggered by electrochemical events at the surface of the biosensor. SARA PoC may be viewed as a cyber-physical system that actuates nanomaterials using smartphone-based electroanalytical testing of samples. This study demonstrates thermal actuation of polymer nanobrushes to detect (sense) bacteria using a cyber-physical systems (CPS) approach. This PoC may catalyze the development of smart sensors capable of actuation at the nanoscale (stimulus-response polymer) and macroscale (non-microfluidic pumping).
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8
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Ogunniyi AD, Tenzin S, Ferro S, Venter H, Pi H, Amorico T, Deo P, Trott DJ. A pH-neutral electrolyzed oxidizing water significantly reduces microbial contamination of fresh spinach leaves. Food Microbiol 2020; 93:103614. [PMID: 32912586 DOI: 10.1016/j.fm.2020.103614] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 06/14/2020] [Accepted: 07/30/2020] [Indexed: 11/30/2022]
Abstract
There are growing demands globally to use safe, efficacious and environmentally friendly sanitizers for post-harvest treatment of fresh produce to reduce or eliminate spoilage and foodborne pathogens. Here, we compared the efficacy of a pH-neutral electrolyzed oxidizing water (Ecas4 Anolyte; ECAS) with that of an approved peroxyacetic acid-based sanitizer (Ecolab Tsunami® 100) in reducing the total microbial load and inoculated Escherichia coli, Salmonella Enteritidis and Listeria innocua populations on post-harvest baby spinach leaves over 10 days. The impact of both sanitizers on the overall quality of the spinach leaves during storage was also assessed by shelf life and vitamin C content measurements. ECAS at 50 ppm and 85 ppm significantly reduced the bacterial load compared to tap water-treated or untreated (control) leaves, and at similar levels (approx. 10-fold reduction) to those achieved using 50 ppm of Ecolab Tsunami® 100. While there were no obvious deleterious effects of treatment with 50 ppm Tsunami® 100 or ECAS at 50 ppm and 85 ppm on plant leaf appearance, tap water-treated and untreated leaves showed some yellowing, bruising and sliming. Given its safety, efficacy and environmentally-friendly characteristics, ECAS could be a viable alternative to chemical-based sanitizers for post-harvest treatment of fresh produce.
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Affiliation(s)
- Abiodun D Ogunniyi
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, Australia.
| | - Sangay Tenzin
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, Australia
| | - Sergio Ferro
- Ecas4 Australia, Unit 8 / 1 London Road, Mile End South, 5031, Australia
| | - Henrietta Venter
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, 5000, Australia
| | - Hongfei Pi
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, Australia
| | - Tony Amorico
- Ecas4 Australia, Unit 8 / 1 London Road, Mile End South, 5031, Australia
| | - Permal Deo
- Health and Biomedical Innovation, Clinical and Health Sciences, University of South Australia, Adelaide, 5000, Australia.
| | - Darren J Trott
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, 5371, Australia
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9
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Chung T, Weller DL, Kovac J. The Composition of Microbial Communities in Six Streams, and Its Association With Environmental Conditions, and Foodborne Pathogen Isolation. Front Microbiol 2020; 11:1757. [PMID: 32849385 PMCID: PMC7403445 DOI: 10.3389/fmicb.2020.01757] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/06/2020] [Indexed: 12/16/2022] Open
Abstract
Surface water used for produce production is a potential source of pre-harvest contamination with foodborne pathogens. Decisions on how to mitigate food safety risks associated with pre-harvest water use currently rely on generic Escherichia coli-based water quality tests, although multiple studies have suggested that E. coli levels are not a suitable indicator of the food safety risks under all relevant environmental conditions. Hence, improved understanding of spatiotemporal variability in surface water microbiota composition is needed to facilitate identification of alternative or supplementary indicators that co-occur with pathogens. To this end, we aimed to characterize the composition of bacterial and fungal communities in the sediment and water fractions of 68 agricultural water samples collected from six New York streams. We investigated potential associations between the composition of microbial communities, environmental factors and Salmonella and/or Listeria monocytogenes isolation. We found significantly different composition of fungal and bacterial communities among sampled streams and among water fractions of collected samples. This indicates that geography and the amount of sediment in a collected water sample may affect its microbial composition, which was further supported by identified associations between the flow rate, turbidity, pH and conductivity, and microbial community composition. Lastly, we identified specific microbial families that were weakly associated with the presence of Salmonella or Listeria monocytogenes, however, further studies on samples from additional streams are needed to assess whether identified families may be used as indicators of pathogen presence.
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Affiliation(s)
- Taejung Chung
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
- Microbiome Center, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Daniel L. Weller
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Jasna Kovac
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
- Microbiome Center, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
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10
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Antunes P, Novais C, Peixe L. Food-to-Humans Bacterial Transmission. Microbiol Spectr 2020; 8:10.1128/microbiolspec.mtbp-0019-2016. [PMID: 31950894 PMCID: PMC10810214 DOI: 10.1128/microbiolspec.mtbp-0019-2016] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Indexed: 12/17/2022] Open
Abstract
Microorganisms vehiculated by food might benefit health, cause minimal change within the equilibrium of the host microbial community or be associated with foodborne diseases. In this chapter we will focus on human pathogenic bacteria for which food is conclusively demonstrated as their transmission mode to human. We will describe the impact of foodborne diseases in public health, the reservoirs of foodborne pathogens (the environment, human and animals), the main bacterial pathogens and food vehicles causing human diseases, and the drivers for the transmission of foodborne diseases related to the food-chain, host or bacteria features. The implication of food-chain (foodborne pathogens and commensals) in the transmission of resistance to antibiotics relevant to the treatment of human infections is also evidenced. The multiplicity and interplay of drivers related to intensification, diversification and globalization of food production, consumer health status, preferences, lifestyles or behaviors, and bacteria adaptation to different challenges (stress tolerance and antimicrobial resistance) from farm to human, make the prevention of bacteria-food-human transmission a modern and continuous challenge. A global One Health approach is mandatory to better understand and minimize the transmission pathways of human pathogens, including multidrug-resistant pathogens and commensals, through food-chain.
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Affiliation(s)
- Patrícia Antunes
- Faculdade de Ciências da Nutrição e Alimentação, Universidade do Porto, Porto, Portugal
| | - Carla Novais
- Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Luísa Peixe
- Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
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11
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Ćwiek K, Bugla-Płoskońska G, Wieliczko A. Salmonella biofilm development: Structure and significance. POSTEP HIG MED DOSW 2019. [DOI: 10.5604/01.3001.0013.7866] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Salmonella spp. is capable of adhering and forming a biofilm on materials of different kinds during their life cycle, contaminating the food chain, thus representing a potential danger for consumers. This review discusses the ability of Salmonella to form biofilm as the main obstacle to reducing the prevalence of these pathogens in food production. The components of Salmonella biofilm, such as cellulose, curli fimbriae, outer membrane proteins (OMPs) and their molecular bases are described, as well as various Salmonella morphotypes (rdar, bdar, pdar and saw). OMPs play very important roles in the cells of Salmonella strains, because they are at the interface between the pathogenic cells and the host tissue and they can contribute to adherence, colonization, virulence and biofilm formation. Furthermore, the importance of quorum sensing is discussed as a crucial factor regulating the properties of biofilm formation and pathogenicity. To further illustrate that biofilm formation is a mechanism used by Salmonella to adapt to various environments, the resistance of Salmonella biofilms against different stress factors including antimicrobials (disinfectants, antibiotics and plant extracts) is described.
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Affiliation(s)
- Katarzyna Ćwiek
- Department of Epizootiology with Clinic of Birds and Exotic Animals, Wrocław University of Environmental and Life Sciences
| | | | - Alina Wieliczko
- Department of Epizootiology with Clinic of Birds and Exotic Animals, Wrocław University of Environmental and Life Sciences
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12
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Ogunniyi AD, Dandie CE, Ferro S, Hall B, Drigo B, Brunetti G, Venter H, Myers B, Deo P, Donner E, Lombi E. Comparative antibacterial activities of neutral electrolyzed oxidizing water and other chlorine-based sanitizers. Sci Rep 2019; 9:19955. [PMID: 31882630 PMCID: PMC6934530 DOI: 10.1038/s41598-019-56248-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/29/2019] [Indexed: 12/16/2022] Open
Abstract
There is increasing demand for safe and effective sanitizers for irrigation water disinfection to prevent transmission of foodborne pathogens to fresh produce. Here we compared the efficacy of pH-neutral electrolyzed oxidizing water (EOW), sodium hypochlorite (NaClO) and chlorine dioxide (ClO2) against single and mixed populations of E. coli, Listeria and Salmonella under a range of pH and organic matter content. EOW treatment of the mixed bacterial suspension resulted in a dose-dependent (<1 mg/L free chlorine), rapid (<2 min) and effective (4-6 Log10) reduction of the microbial load in water devoid of organic matter under the range of pH conditions tested (pH, 6.0, 7.0, 8.4 and 9.2). The efficacy of EOW containing 5 mg/L free chlorine was unaffected by increasing organic matter, and compared favourably with equivalent concentrations of NaClO and ClO2. EOW at 20 mg/L free chlorine was more effective than NaClO and ClO2 in reducing bacterial populations in the presence of high (20-100 mg/L) dissolved organic carbon, and no regrowth or metabolic activity was observed for EOW-treated bacteria at this concentration upon reculturing in rich media. Thus, EOW is as effective or more effective than other common chlorine-based sanitizers for pathogen reduction in contaminated water. EOW's other characteristics, such as neutral pH and ease of handling, indicate its suitability for fresh produce sanitation.
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Affiliation(s)
- Abiodun D Ogunniyi
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia.
| | - Catherine E Dandie
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Sergio Ferro
- Ecas4 Australia Pty Ltd, 8/1 London Road, Mile End South, South Australia, Australia
| | - Barbara Hall
- Plant Health and Biosecurity, SARDI, Adelaide, South Australia, Australia
| | - Barbara Drigo
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Gianluca Brunetti
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Henrietta Venter
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Baden Myers
- Natural and Built Environments Research Centre, School of Natural and Built Environments, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Permal Deo
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Erica Donner
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Enzo Lombi
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
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13
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Marik CM, Anderson-Coughlin B, Gartley S, Craighead S, Bradshaw R, Kulkarni P, Sharma M, Kniel KE. The efficacy of zero valent iron-sand filtration on the reduction of Escherichia coli and Listeria monocytogenes in surface water for use in irrigation. ENVIRONMENTAL RESEARCH 2019; 173:33-39. [PMID: 30884436 DOI: 10.1016/j.envres.2019.02.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 02/17/2019] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
The use of surface and recycled water sources for irrigation can reduce demand on critical groundwater resources. Treatment or mitigation may be necessary for the use of these alternative water sources in order to reduce risk associated with microbial pathogens present in the water. In this study, the efficacy of a zero-valent iron (ZVI) sand filter was assessed for the reduction of Listeria monocytogenes and Escherichia coli in surface water. Water recovered from an agricultural pond was inoculated with E. coli TVS353 and an environmental L. monocytogenes isolate at 7 Log10 CFU/mL and horizontally filtered over a six-month period through a PVC pipe filter, filled with 35%:65% (volume:volume) ZVI:sand or sand alone. Filtered water was used to irrigate lettuce and bacterial persistence on lettuce leaves was determined for 7 days post-irrigation. Both ZVI:sand-filtered water and sand-filtered water contained significantly (p < 0.005) lower levels of E. coli and L. monocytogenes compared to initial unfiltered inoculated water. Population reductions of E. coli and L. monocytogenes were comparable after sand filtration. However, ZVI:sand filtration resulted in significantly greater population reductions of L. monocytogenes (P < 0.05) compared to E. coli. Populations of E. coli on leaves of lettuce plants irrigated with ZVI:sand-filtered water were not significantly lower than populations on plants irrigated with sand-filtered irrigation water over the 7-day period. However, populations of L. monocytogenes on lettuce leaves irrigated with ZVI-treated water were significantly lower than counts on plants irrigated with sand-filtered irrigation water on days 3 and 4 post irrigation (p = 0.052 and p = 0.042 for days 3 and 4, respectively. The differences observed in reductions of L. monocytogenes and E. coli by ZVI filtration is due to the differing effect that ZVI disruption has on Gram-positive and Gram-negative cell walls and membranes. ZVI- sand filters show promising results as an inexpensive on-farm technology for the mitigation of enteric foodborne bacterial populations in pond water over a six-month period.
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Affiliation(s)
- Claire M Marik
- Department of Animal and Food Science, University of Delaware, Newark, DE, USA
| | | | - Samantha Gartley
- Department of Animal and Food Science, University of Delaware, Newark, DE, USA
| | - Shani Craighead
- Department of Animal and Food Science, University of Delaware, Newark, DE, USA
| | - Rhodel Bradshaw
- US Department of Agriculture - ARS, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA
| | - Prachi Kulkarni
- US Department of Agriculture - ARS, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA
| | - Manan Sharma
- US Department of Agriculture - ARS, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, USA
| | - Kalmia E Kniel
- Department of Animal and Food Science, University of Delaware, Newark, DE, USA.
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14
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Haymaker J, Sharma M, Parveen S, Hashem F, May EB, Handy ET, White C, East C, Bradshaw R, Micallef SA, Callahan MT, Allard S, Anderson B, Craighead S, Gartley S, Vanore A, Kniel KE, Solaiman S, Bui A, Murray R, Craddock HA, Kulkarni P, Foust D, Duncan R, Taabodi M, Sapkota AR. Prevalence of Shiga-toxigenic and atypical enteropathogenic Escherichia coli in untreated surface water and reclaimed water in the Mid-Atlantic U.S. ENVIRONMENTAL RESEARCH 2019; 172:630-636. [PMID: 30878734 DOI: 10.1016/j.envres.2019.02.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 02/08/2019] [Accepted: 02/12/2019] [Indexed: 06/09/2023]
Abstract
The microbial quality of irrigation water has increasingly become a concern as a source of contamination for fruits and vegetables. Non-traditional sources of water are being used by more and more growers in smaller, highly diversified farms in the Mid-Atlantic region of the U.S. Shiga-toxigenic E. coli (STEC) have been responsible for several outbreaks of infections associated with the consumption of leafy greens. Our study evaluated the prevalence of the "big seven" STEC serogroups and the associated enterohemorrhagic E. coli (EHEC) virulence factors (VF) genes in conventional and nontraditional irrigation waters in the Mid-Atlantic region of the U.S. Water samples (n = 510) from 170 sampling events were collected from eight untreated surface water sites, two wastewater reclamation facilities, and one vegetable processing plant, over a 12-month period. Ten liters of water were filtered through Modified Moore swabs (MMS); swabs were then enriched into Universal Pre-enrichment Broth (UPB), followed by enrichment into non-O157 STEC R&F broth and isolation on R & F non-O157 STEC chromogenic plating medium. Isolates (n = 2489) from enriched MMS from water samples were screened for frequently reported STEC serogroups that cause foodborne illness: O26, O45, O103, O111, O121, O145, and O157, along with VF genes stx1, stx2, eae, and ehxA. Through this screening process, STEC isolates were found in 2.35% (12/510) of water samples, while 9.0% (46/510) contained an atypical enteropathogenic E. coli (aEPEC) isolate. The eae gene (n = 88 isolates) was the most frequently detected EHEC VF of the isolates screened. The majority of STEC isolates (stx1 or stx2) genes mainly came from either a pond or reclamation pond water site on two specific dates, potentially indicating that these isolates were not spatially or temporally distributed among the sampling sites. STEC isolates at reclaimed water sites may have been introduced after wastewater treatment. None of the isolates containing eae were determined to be Escherichia albertii. Our work showed that STEC prevalence in Mid-Atlantic untreated surface waters over a 12-month period was lower than the prevalence of atypical EPEC.
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Affiliation(s)
- Joseph Haymaker
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Manan Sharma
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, United States.
| | - Salina Parveen
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Fawzy Hashem
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Eric B May
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Eric T Handy
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, United States
| | - Chanelle White
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Cheryl East
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, United States
| | - Rhodel Bradshaw
- United States Department of Agriculture, Agricultural Research Service, Northeast Area, Beltsville Agricultural Research Center, Environmental Microbial and Food Safety Laboratory, Beltsville, MD, United States
| | - Shirley A Micallef
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, United States
| | - Mary Theresa Callahan
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, United States
| | - Sarah Allard
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
| | - Brienna Anderson
- University of Delaware, Department of Animal and Food Sciences, Newark, DE 19716, United States
| | - Shani Craighead
- University of Delaware, Department of Animal and Food Sciences, Newark, DE 19716, United States
| | - Samantha Gartley
- University of Delaware, Department of Animal and Food Sciences, Newark, DE 19716, United States
| | - Adam Vanore
- University of Delaware, Department of Animal and Food Sciences, Newark, DE 19716, United States
| | - Kalmia E Kniel
- University of Delaware, Department of Animal and Food Sciences, Newark, DE 19716, United States
| | - Sultana Solaiman
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, United States
| | - Anthony Bui
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
| | - Rianna Murray
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
| | - Hillary A Craddock
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
| | - Prachi Kulkarni
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
| | - Derek Foust
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Rico Duncan
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Maryam Taabodi
- University of Maryland Eastern Shore, Department of Agriculture and Resource Sciences, Princess Anne, MD, United States
| | - Amy R Sapkota
- Maryland Institute for Applied Environmental Health, University of Maryland School of Public Health, College Park, MD, United States
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15
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Erickson MC, Liao JY, Payton AS, Cook PW, Bakker HCDEN, Bautista J, Díaz-Pérez JC. Survival of Salmonella enterica and Escherichia coli O157:H7 Sprayed onto the Foliage of Field-Grown Cabbage Plants. J Food Prot 2019; 82:479-485. [PMID: 30806554 DOI: 10.4315/0362-028x.jfp-18-326] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
To reduce the number of cabbage pathogen outbreaks, it is essential to understand the fate of enteric pathogens that contaminate plants in the field. To assist in that effort, two independent trials were conducted with a red cultivar (cv. Red Dynasty) and a green cultivar (cv. Bravo F1) of field-grown cabbage ( Brassica oleracea var. capitata). In the first trial, plants with small heads were sprayed with an inoculum containing both attenuated Salmonella enterica Typhimurium and Escherichia coli O157:H7 (5.0 log CFU/mL). Initial pathogen levels (ca. 3.9 log CFU per head), determined through plate count enumeration (limit of detection was 1.3 log CFU/g), dropped precipitously such that 2 days later, they could not be detected by enrichment culture in 22 to 35% of the heads. However, subsequent declines were at a slower rate; no differences were observed between red and green cabbage heads ( P > 0.05), and heads were still positive for the pathogens 22 days after being sprayed with the inoculum. As a result, the logistic model revealed that for every 2 days contaminated cabbage heads remained in the field, the probability of finding a positive sample decreased by a factor of 1.1 (95% confidence interval from 1.0 to 1.2, P = 0.0022) and 1.2 (95% confidence interval from 1.0 to 1.4, P ≤ 0.0001) for Salmonella and E. coli O157:H7, respectively. In the second trial occurring 2 weeks later, plants with medium red or green cabbage heads were sprayed with an inoculum at a dose of 3.5 log CFU/mL. A similar decay in prevalence over time occurred for green cabbage as in trial 1; however, pathogen decline in red cabbage was less in trial 2 than in trial 1. The extended persistence of pathogens in cabbage heads exhibited in both trials infers that harvest of contaminated cabbage destined for raw consumption is risky. Additional field studies are necessary to determine whether similar pathogen fates occur in other regions or climates and to clarify the effect of the maturity of red cabbage on pathogen inactivation.
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Affiliation(s)
- Marilyn C Erickson
- 1 Center for Food Safety, Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797
| | - Jye-Yin Liao
- 1 Center for Food Safety, Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797
| | - Alison S Payton
- 1 Center for Food Safety, Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797
| | - Peter W Cook
- 1 Center for Food Safety, Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797
| | - Henk C DEN Bakker
- 1 Center for Food Safety, Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797
| | - Jesus Bautista
- 2 Department of Horticulture, University of Georgia, 2360 Rainwater Road, Tifton, Georgia 31793-5766, USA
| | - Juan Carlos Díaz-Pérez
- 2 Department of Horticulture, University of Georgia, 2360 Rainwater Road, Tifton, Georgia 31793-5766, USA
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16
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Paz-Méndez AM, Lamas A, Vázquez B, Miranda JM, Cepeda A, Franco CM. Effect of Food Residues in Biofilm Formation on Stainless Steel and Polystyrene Surfaces by Salmonella enterica Strains Isolated from Poultry Houses. Foods 2017; 6:E106. [PMID: 29186017 PMCID: PMC5742774 DOI: 10.3390/foods6120106] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/26/2017] [Accepted: 11/27/2017] [Indexed: 12/13/2022] Open
Abstract
Salmonella spp. is a major food-borne pathogen around the world. The ability of Salmonella to produce biofilm is one of the main obstacles in reducing the prevalence of these bacteria in the food chain. Most of Salmonella biofilm studies found in the literature used laboratory growth media. However, in the food chain, food residues are the principal source of nutrients of Salmonella. In this study, the biofilm formation, morphotype, and motility of 13 Salmonella strains belonging to three different subspecies and isolated from poultry houses was evaluated. To simulate food chain conditions, four different growth media (Tryptic Soy Broth at 1/20 dilution, milk at 1/20 dilution, tomato juice, and chicken meat juice), two different surfaces (stainless steel and polystyrene) and two temperatures (6 °C and 22 °C) were used to evaluate the biofilm formation. The morphotype, motility, and biofilm formation of Salmonella was temperature-dependent. Biofilm formation was significantly higher with 1/20 Tryptic Soy Broth in all the surfaces and temperatures tested, in comparison with the other growth media. The laboratory growth medium 1/20 Tryptic Soy Broth enhanced biofilm formation in Salmonella. This could explain the great differences in biofilm formation found between this growth medium and food residues. However, Salmonella strains were able to produce biofilm on the presence of food residues in all the conditions tested. Therefore, the Salmonella strain can use food residues to produce biofilm on common surfaces of the food chain. More studies combining more strains and food residues are necessary to fully understand the mechanism used by Salmonella to produce biofilm on the presence of these sources of nutrients.
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Affiliation(s)
- Alba María Paz-Méndez
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
| | - Alexandre Lamas
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
| | - Beatriz Vázquez
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
| | - José Manuel Miranda
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
| | - Alberto Cepeda
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
| | - Carlos Manuel Franco
- Laboratorio de Higiene, Inspección y Control de Alimentos, Dpto. de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
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