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Busch A, Becker A, Schotte U, Plötz M, Abdulmawjood A. Mpl-Gene-Based Loop-Mediated Isothermal Amplification Assay for Specific and Rapid Detection of Listeria monocytogenes in Various Food Samples. Foodborne Pathog Dis 2022; 19:463-472. [PMID: 35099299 DOI: 10.1089/fpd.2021.0080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Listeria monocytogenes represents a high risk in food and can trigger potentially fatal listeriosis. The objective of this study was to detect L. monocytogenes in food using the LAMP method in a fast, specific, sensitive manner and thus to preventively test food for the presence of the target species. The reaction was performed and established using the portable real-time fluorometer Genie® II (OptiGene Ltd., Horsham, United Kingdom). In this new assay, six LAMP primers targeted the mpl-gene sequence of L. monocytogenes. A total of 148 different isolates, including 105 L. monocytogenes and 43 non-L. monocytogenes strains, were tested. Analytical sensitivity was determined based on different DNA- and cell concentrations. The detection limit with a detection rate of 100% was 5 pg of DNA or 275 colony-forming units (CFU) per reaction. Artificially contaminated minced beef and grated mozzarella were also tested. The assay was 100% successful to detect an initial bacterial contamination of 0.4-4 CFU g-1 food after 24 h enrichment in half-Fraser broth. Finally, natively contaminated samples were tested in comparison to the microbiological reference method and real-time polymerase chain reaction. Native sample testing revealed 100% consistent findings between LAMP and the standard culture method after first enrichment for 24 h. In addition, a rapid colony-confirmation method was established that enabled reliable identification of L. monocytogenes isolates on different selective culture media using a simplified DNA extraction by boiling. This study showed that the developed assay was able to determine whether a food is safe with respect to the food-safety criteria of 100 CFU per gram, according to standards of the European Union, for L. monocytogenes and provided faster results than the cultural reference method.
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Affiliation(s)
- Annemarie Busch
- Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Hannover, Germany
| | - André Becker
- Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Ulrich Schotte
- Department A (Veterinary Medicine), Central Institute of the Bundeswehr Medical Service Kiel, Kronshagen, Germany
| | - Madeleine Plötz
- Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Amir Abdulmawjood
- Institute of Food Quality and Food Safety, University of Veterinary Medicine Hannover, Hannover, Germany
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2
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Esmaeilian S, Rotabakk BT, Lerfall J, Jakobsen AN, Abel N, Sivertsvik M, Olsen A. The use of soluble gas stabilization technology on food – A review. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.09.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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3
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Cheng T, Ramaswamy H, Xu R, Liu Q, Lan R, Wang S. Fifty Ohm radio frequency heating treatment under controlled atmosphere for inactivating Escherichia coli ATCC 25922 inoculated on almond kernels. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109124] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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4
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McNulty MJ, Gleba Y, Tusé D, Hahn-Löbmann S, Giritch A, Nandi S, McDonald KA. Techno-economic analysis of a plant-based platform for manufacturing antimicrobial proteins for food safety. Biotechnol Prog 2019; 36:e2896. [PMID: 31443134 PMCID: PMC7027456 DOI: 10.1002/btpr.2896] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/23/2019] [Accepted: 08/19/2019] [Indexed: 12/25/2022]
Abstract
Continuous reports of foodborne illnesses worldwide and the prevalence of antibiotic-resistant bacteria mandate novel interventions to assure the safety of our food. Treatment of a variety of foods with bacteriophage-derived lysins and bacteriocin-class antimicrobial proteins has been shown to protect against high-risk pathogens at multiple intervention points along the food supply chain. The most significant barrier to the adoption of antimicrobial proteins as a food safety intervention by the food industry is the high production cost using current fermentation-based approaches. Recently, plants have been shown to produce antimicrobial proteins with accumulation as high as 3 g/kg fresh weight and with demonstrated activity against major foodborne pathogens. To investigate potential economic advantages and scalability of this novel platform, we evaluated a highly efficient transgenic plant-based production process. A detailed process simulation model was developed to help identify economic "hot spots" for research and development focus including process operating parameters, unit operations, consumables, and/or raw materials that have the most significant impact on production costs. Our analyses indicate that the unit production cost of antimicrobial proteins in plants at commercial scale for three scenarios is $3.00-6.88/g, which can support a competitive selling price to traditional food safety treatments.
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Affiliation(s)
- Matthew J McNulty
- Department of Chemical Engineering, University of California, Davis, California
| | | | | | | | | | - Somen Nandi
- Department of Chemical Engineering, University of California, Davis, California.,Global HealthShare® Initiative, University of California, Davis, California
| | - Karen A McDonald
- Department of Chemical Engineering, University of California, Davis, California.,Global HealthShare® Initiative, University of California, Davis, California
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5
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Role of food sanitising treatments in inducing the ‘viable but nonculturable’ state of microorganisms. Food Control 2018. [DOI: 10.1016/j.foodcont.2018.04.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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6
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Wang X, Devlieghere F, Geeraerd A, Uyttendaele M. Thermal inactivation and sublethal injury kinetics of Salmonella enterica and Listeria monocytogenes in broth versus agar surface. Int J Food Microbiol 2017; 243:70-77. [DOI: 10.1016/j.ijfoodmicro.2016.12.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 11/07/2016] [Accepted: 12/12/2016] [Indexed: 12/22/2022]
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7
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Thermal inactivation kinetics of surface contaminating Listeria monocytogenes on vacuum-packaged agar surface and ready-to-eat sliced ham and sausage. Food Res Int 2016; 89:843-849. [DOI: 10.1016/j.foodres.2016.10.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/08/2016] [Accepted: 10/14/2016] [Indexed: 11/22/2022]
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8
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Heinrich V, Zunabovic M, Nehm L, Bergmair J, Kneifel W. Influence of argon modified atmosphere packaging on the growth potential of strains of Listeria monocytogenes and Escherichia coli. Food Control 2016. [DOI: 10.1016/j.foodcont.2015.06.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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9
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Favourable effects of soluble gas stabilisation and modified atmosphere for supressing regrowth of high pressure treated Listeria innocua. Food Control 2015. [DOI: 10.1016/j.foodcont.2014.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Juzwa W, Myszka K, Białas W, Dobrucka R, Konieczny P, Czaczyk K. Investigation of the effectiveness of disinfectants against planktonic and biofilm forms of P. aeruginosa and E. faecalis cells using a compilation of cultivation, microscopic and flow cytometric techniques. BIOFOULING 2015; 31:587-597. [PMID: 26313563 DOI: 10.1080/08927014.2015.1075126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This study evaluated the effectiveness of selected disinfectants against bacterial cells within a biofilm using flow cytometry, the conventional total viable count test and scanning electron microscopy (SEM). A flow cytometric procedure based on measurement of the cellular redox potential (CRP) was demonstrated to have potential for the rapid evaluation of activity against biofilm and planktonic forms of microbes. Quaternary ammonium compound-based disinfectant (QACB) demonstrated a higher level of anti-microbial activity than a performic acid preparation (PAP), with mean CRP values against P. aeruginosa cells of 2 and 1.33 relative fluorescence units (RFU) vs 63.33 and 61.33 RFU for 8 and 24 h cultures respectively. Flow cytometric evaluation of the anti-biofilm activity demonstrated a higher efficacy of QACB compared to PAP for P. aeruginosa cells of 1 and 0.66 RFU vs 18.33 and 22.66 RFU for 8 and 24 h cultures respectively. SEM images of treated P. aeruginosa cells demonstrated disinfectant-specific effects on cell morphology.
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Affiliation(s)
- Wojciech Juzwa
- a Department of Biotechnology and Food Microbiology , Poznań University of Life Sciences , Poznań , Poland
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11
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Noriega E, Velliou EG, Van Derlinden E, Mertens L, Van Impe JFM. Role of growth morphology in the formulation of NaCl-based selective media for injury detection of Escherichia coli, Salmonella Typhimurium and Listeria innocua. Food Res Int 2014; 64:402-411. [PMID: 30011667 DOI: 10.1016/j.foodres.2014.06.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/26/2014] [Accepted: 06/29/2014] [Indexed: 11/26/2022]
Abstract
Sublethal injury (SI) poses major public health concerns since injured cells are responsible for serious limitations in food diagnostics and are susceptible to recovery, often developing adaptive stress responses. Detection of SI is based on the difference in plate counts between non-selective media, which represent the total cell population, and selective media, to which injured cells become sensitive. Selective media for detection of sublethal membrane damage are often based on NaCl supplement, although there is a lack of consensus in the literature about appropriate levels. Planktonic cells are generally used to investigate SI mechanisms, although they often exhibit different stress tolerance than cell colonies in/on solid food (model) systems. In this work, the effect of growth morphology, colony size and concentration of the gelling agent in the growth media, on the maximum non-inhibitory NaCl concentration in the plating medium was assessed for Escherichia coli, Salmonella Typhimurium and Listeria innocua. Stationary phase cultures of planktonic cells and large and small colonies grown in either 1.5% (w/v) xanthan gum-based system or 2.5% (w/v) xanthan gum-based system exhibited significantly different viable counts and osmotolerance. The effect of cell arrangement and xanthan gum percentage in the growth media depended on the microorganism under investigation. Additionally, differences in the maximum non-inhibitory concentration were evident, with 5.0% (w/v) NaCl for the Gram-negative bacteria and 6.5% (w/v), for L. innocua. Different extent of colony shrinkage and morphological damage was observed as NaCl concentration in the plating medium increased. This information will contribute to define NaCl-based selective media for accurate SI detection under realistic scenarios.
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Affiliation(s)
- Estefanía Noriega
- CPMF(2) - Flemish Cluster Predictive Microbiology in Foods, http://www.cpmf2.be, Belgium; BioTeC - Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
| | - Eirini G Velliou
- CPMF(2) - Flemish Cluster Predictive Microbiology in Foods, http://www.cpmf2.be, Belgium; BioTeC - Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
| | - Eva Van Derlinden
- CPMF(2) - Flemish Cluster Predictive Microbiology in Foods, http://www.cpmf2.be, Belgium; BioTeC - Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
| | - Laurence Mertens
- CPMF(2) - Flemish Cluster Predictive Microbiology in Foods, http://www.cpmf2.be, Belgium; BioTeC - Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
| | - Jan F M Van Impe
- CPMF(2) - Flemish Cluster Predictive Microbiology in Foods, http://www.cpmf2.be, Belgium; BioTeC - Chemical and Biochemical Process Technology and Control, Department of Chemical Engineering, KU Leuven, Leuven, Belgium.
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Noriega E, Velliou E, Van Derlinden E, Mertens L, Van Impe JFM. Effect of cell immobilization on heat-induced sublethal injury of Escherichia coli, Salmonella Typhimurium and Listeria innocua. Food Microbiol 2013; 36:355-64. [PMID: 24010617 DOI: 10.1016/j.fm.2013.06.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/15/2013] [Accepted: 06/14/2013] [Indexed: 10/26/2022]
Abstract
The occurrence of sublethally injured cells in foods poses major public health concerns and is an essential aspect when assessing the microbial response to food preservation strategies, yet there is limited research dealing with its specific implications for mild heating. All available studies so far have been performed in broths colonized by planktonic cells, although their susceptibility to lethal agents has often been reported to be markedly different to the stress tolerance of cell colonies developed in solid foods. In this work, the effect of planktonic and colony growth, as well as the influence of colony density on sublethal injury induced by mild heating of Escherichia coli, Salmonella Typhimurium and Listeria innocua were assessed in food model systems. Detection of injured survivors relied on their inability to form visible colonies on salt-based selective media, which do not affect the growth of healthy cells. Sublethal injury (SI) increased rapidly with shorter exposure times and afterwards, decreased progressively, suggesting a mechanism of cumulative damage triggering lethal instead of SI. Cell arrangement affected the degree of SI, higher values being generally found for gelified systems, although the effect of colony density depended on the target microorganism. This information is essential for optimizing the design of food safety assurance systems.
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Ferrario M, Guerrero S, Alzamora SM. Study of Pulsed Light-Induced Damage on Saccharomyces cerevisiae in Apple Juice by Flow Cytometry and Transmission Electron Microscopy. FOOD BIOPROCESS TECH 2013. [DOI: 10.1007/s11947-013-1121-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Kim EG, Ryu JH, Kim H. Effect of Chlorine Dioxide Treatment and Storage in a Modified Atmosphere on the Inactivation of Cronobacter
spp. on Radish Seeds. J Food Saf 2013. [DOI: 10.1111/jfs.12037] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eun-Gyeong Kim
- Department of Food and Nutrition; Wonkwang University; Iksan Jeonbuk 570-749 Korea
| | - Jee-Hoon Ryu
- Graduate School of Life Sciences and Biotechnology; Korea University; Seoul 136-791 Korea
| | - Hoikyung Kim
- Department of Food and Nutrition; Wonkwang University; Iksan Jeonbuk 570-749 Korea
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17
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Ayari S, Dussault D, Hayouni EA, Vu KD, Hamdi M, Lacroix M. Response of Bacillus cereus vegetative cells after exposure to repetitive sublethal radiation processing in combination with nisin. Food Microbiol 2012; 32:361-70. [DOI: 10.1016/j.fm.2012.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 07/12/2012] [Accepted: 07/30/2012] [Indexed: 11/29/2022]
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Poli VFS, Thorsen L, Olesen I, Wik MT, Jespersen L. Differentiation of the virulence potential of Campylobacter jejuni strains by use of gene transcription analysis and a Caco-2 assay. Int J Food Microbiol 2012; 155:60-8. [DOI: 10.1016/j.ijfoodmicro.2012.01.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 01/20/2012] [Accepted: 01/22/2012] [Indexed: 01/05/2023]
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Pataro G, Muñoz A, Palgan I, Noci F, Ferrari G, Lyng J. Bacterial inactivation in fruit juices using a continuous flow Pulsed Light (PL) system. Food Res Int 2011. [DOI: 10.1016/j.foodres.2011.04.048] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Arvanitoyannis IS, Bosinas KP, Bouletis AD, Gkagtzis DC, Hadjichristodoulou C, Papaloucas C. Study of the effect of atmosphere modification in conjunction with honey on the extent of shelf life of Greek bakery delicacy "touloumpaki". Anaerobe 2011; 17:300-2. [PMID: 21549213 DOI: 10.1016/j.anaerobe.2011.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 04/10/2011] [Accepted: 04/12/2011] [Indexed: 11/25/2022]
Abstract
The aim of the present work was to evaluate the effect of atmosphere modification on microbial (mesophiles, yeast and molds) qualities, color, pH, texture and water activity of the Greek bakery product "touloumpaki". Samples were stored under MAP (60% CO(2)) either alone or with the addition of honey syrup for 16 days at room temperature (22-24 °C). Texture was better maintained under MAP and the addition of honey prevented the increase of shear force needed (1.498 and 3.20 for samples with and without honey). Honey inhibited the growth of yeasts on samples stored under MAP (1.6 and 2.02 log CFU/g for samples under MAP with and without honey respectively) while multivariant analysis showed that MAP and honey acted synergistically in confining yeasts. Presence of honey restrained the mesophilic growth until the end of storage period (5.21 and 4.29 log CFU/g for MAP and control samples respectively) while MAP did not have any beneficial effect. Water activity (a(W) < 0.754) was strongly associated with reduced mesophile growth. Lightness values showed a significant decrease during time with no significant changes among treatments in both internal layers and external surface of the product.
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Affiliation(s)
- Ioannis S Arvanitoyannis
- School of Agricultural Sciences, Department of Agriculture, Ichthyology and Aquatic Environment, University of Thessaly, Fytokou Str, 38446 Nea Ionia Magnesias, Volos, Hellas, Greece.
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Rajkovic A, Smigic N, Devlieghere F. Contemporary strategies in combating microbial contamination in food chain. Int J Food Microbiol 2010; 141 Suppl 1:S29-42. [DOI: 10.1016/j.ijfoodmicro.2009.12.019] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 12/07/2009] [Accepted: 12/14/2009] [Indexed: 10/20/2022]
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Rajkovic A, Tomic N, Smigic N, Uyttendaele M, Ragaert P, Devlieghere F. Survival of Campylobacter jejuni on raw chicken legs packed in high-oxygen or high-carbon dioxide atmosphere after the decontamination with lactic acid/sodium lactate buffer. Int J Food Microbiol 2010; 140:201-6. [DOI: 10.1016/j.ijfoodmicro.2010.03.034] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 03/18/2010] [Accepted: 03/20/2010] [Indexed: 10/19/2022]
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Smigic N, Rajkovic A, Nielsen DS, Arneborg N, Siegumfeldt H, Devlieghere F. Survival of lactic acid and chlorine dioxide treated Campylobacter jejuni under suboptimal conditions of pH, temperature and modified atmosphere. Int J Food Microbiol 2010; 141 Suppl 1:S140-6. [PMID: 20149937 DOI: 10.1016/j.ijfoodmicro.2010.01.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 01/18/2010] [Accepted: 01/19/2010] [Indexed: 11/29/2022]
Abstract
As mild decontamination treatments are gaining more and more interest due to increased consumer demands for fresh foods, it is of great importance to establish the influence of decontamination treatments on the subsequent bacterial behaviour under suboptimal storage conditions. For this purpose Campylobacter jejuni cells treated with lactic acid (LA, 3% lactic acid, pH 4.0, 2 min) or chlorine dioxide (ClO(2), 20 ppm, 2 min) were inoculated in Bolton broth (pH 6.0) and incubated under 80% O(2)/20% N(2), 80% CO(2)/20% N(2), air or micro-aerophilic (10% CO(2)/85% N(2)/5% O(2)) atmosphere, at 4 degrees C during 7 days. Treatment with water served as a control. The most suppressive atmosphere for the survival of C. jejuni was O(2)-rich atmosphere, followed by air, micro-aerophilic and CO(2)-rich atmosphere. The survival of C. jejuni was dependent on the type of initial decontamination treatment, with water treated cells showing the greatest survival followed by LA and ClO(2) treated cells. Intracellular pH (pH(i)) of individual C. jejuni cells was determined using Fluorescence Ratio Imaging Microscopy (FRIM). At all tested conditions, different subpopulation of the cells could be distinguished based on their pH(i) values. The pH(i) response was independent on the surrounding atmosphere since similar distribution of the subpopulations was observed for all tested atmospheres. However, the pH(i) response was dependent on the initial decontamination treatment. The investigation of intracellular parameters gave an insight into pathogen behaviour under stressful conditions at intracellular level. The results obtained in this study highlighted the importance of combining decontamination technologies with subsequent preservation techniques to the control survival and growth of foodborne pathogens.
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Affiliation(s)
- Nada Smigic
- Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Food2Know, Ghent, Belgium
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Smigic N, Rajkovic A, Antal E, Medic H, Lipnicka B, Uyttendaele M, Devlieghere F. Treatment of Escherichia coli O157:H7 with lactic acid, neutralized electrolyzed oxidizing water and chlorine dioxide followed by growth under sub-optimal conditions of temperature, pH and modified atmosphere. Food Microbiol 2009; 26:629-37. [PMID: 19527839 DOI: 10.1016/j.fm.2009.04.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 04/21/2009] [Accepted: 04/25/2009] [Indexed: 11/27/2022]
Abstract
The utilization of sub-lethal decontamination treatments gains more and more interest due to the increased consumers' demand for fresh, minimally processed and convenient food products. These products rely on cold chain and hurdle (combination) technology to provide microbiological safety and quality during their shelf life. To investigate the ability of surviving cells to resuscitate and grow in a food simulating environment, sub-lethal decontamination treatments were coupled with subsequent storage under sub-optimal growth conditions. For this purpose chlorine dioxide (ClO2) and neutralized electrolyzed oxidizing water (NEW)-treated cultures of Escherichia coli O157:H7 were inoculated in TSB-YE of pH 5.8 and aw 0.99, and stored at 10 degrees C, 12.5 degrees C and 15 degrees C, under four different atmospheres (0%, 30% and 60% CO2 balanced with N2, and air). Due to the severity of injury, lactic acid-treated cells were inoculated in TSB-YE pH 7.0. Data obtained reveal that the fraction of sub-lethally injured E. coli O157:H7 undergoes an additional inhibitory effect during the storage period under of sub-optimal conditions. Observed extension in the lag growth phase was a direct consequence prior sub-lethal injury. The effects of liquid ClO2 and NEW were less pronounced in comparison to lactic acid. The current study signifies the potential utilization of appropriate combination of different extrinsic and intrinsic factors in the elimination or growth inhibition of food-borne pathogens.
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Affiliation(s)
- Nada Smigic
- Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Ghent University, Ghent, Belgium
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Rajkovic A, Smigic N, Uyttendaele M, Medic H, de Zutter L, Devlieghere F. Resistance of Listeria monocytogenes, Escherichia coli O157:H7 and Campylobacter jejuni after exposure to repetitive cycles of mild bactericidal treatments. Food Microbiol 2009; 26:889-95. [PMID: 19835777 DOI: 10.1016/j.fm.2009.06.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 05/26/2009] [Accepted: 06/05/2009] [Indexed: 11/17/2022]
Abstract
While maintaining nutritional and sensorial attributes of fresh foods mild processing technologies generally deliver microbiologically perishable food products. Currently little information exists on possible increase in the resistance of pathogens after repetitive exposure to mild (sub-lethal) treatments. Multiple strain-cocktails of Listeria monocytogenes, Escherichia coli O157:H7 and Campylobacter jejuni were exposed to 20 consecutive cycles of sub-lethal inactivation by three different techniques. Used techniques comprised inactivation with lactic acid (LA), chlorine dioxide (ClO(2)) and intense light pulses (ILP). Results showed that the selection of resistant cells was both species and technique dependent. While repetitive cycles of ClO(2) treatment did not result in increased resistance, repetitive inactivation with LA yielded L. monocytogenes culture of higher resistance in comparison to the parental culture. The increased resistance, expressed as decreased level of reduction in bacterial counts in subsequent inactivation cycles, was also observed with ILP for both L. monocytogenes and E. coli O157:H7 strains. Visual trend observations were confirmed through statistical linear regression analysis. No such effects were noted for C. jejuni which became undetectable after first 2-5 cycles. Current findings indicate the ability of foodborne pathogens to adapt to mild bactericidal treatments creating new challenges in risk assessment and more specifically in hazard analysis.
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Affiliation(s)
- Andreja Rajkovic
- Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Gent, Belgium
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26
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Influence of partial inactivation on growth of Listeria monocytogenes under sub-optimal conditions of increased NaCl concentration or increased acidity. INNOV FOOD SCI EMERG 2009. [DOI: 10.1016/j.ifset.2008.11.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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