1
|
Gana J, Gcebe N, Moerane R, Ngoshe YB, Moabelo K, Adesiyun AA. Detection of Pathogenic Serogroups and Virulence Genes in Listeria monocytogenes Strains Isolated from Beef and Beef Products Retailed in Gauteng Province, South Africa, Using Phenotypic and Polymerase Chain Reaction (PCR)-Based Methods. Int J Microbiol 2024; 2024:8891963. [PMID: 38510936 PMCID: PMC10954364 DOI: 10.1155/2024/8891963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/27/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
South Africa recently (2017-18) experienced the largest outbreak of human listeriosis in the world caused by L. monocytogenes following the consumption of "polony," a ready-to-eat meat product. Most (59%) cases originated from Gauteng province, South Africa. As a follow-up study to the outbreak, we used standard bacteriological and molecular methods to determine the prevalence of pathogenic and virulent serogroups of L. monocytogenes in various beef and beef products retailed in Gauteng province, South Africa. The overall prevalence of Listeria spp. was 28% (112/400), comprising Listeria monocytogenes (9.3%), Listeria innocua (16.3%), and Listeria welshimeri (2.5%) (p < 0.001). It is crucial to have detected that the region (p=0.036), type of product (p=0.032), and temperature at storage (p=0.011) significantly affected the occurrence of L. monocytogenes in beef products. It is alarming that pathogenic serogroups 4b-4d-4e (51.4%) and 1/2a-3a (43.2%) were detected among the isolates of L. monocytogenes. Importantly, they were all carriers of seven virulence-associated genes (hlyA, inlB, plcA, iap, inlA, inlC, and inlJ). Our study also demonstrated that 16.7% of "polony" samples investigated were contaminated with L. monocytogenes. Considering that pathogenic and virulent L. monocytogenes contaminated beef and beef products retailed in South Africa, the food safety risk posed to consumers remains and cannot be ignored. Therefore, it is imperative to reduce the contamination of these products with L. monocytogenes during beef production, processing, and retailing to avoid future outbreaks of human listeriosis in the country.
Collapse
Affiliation(s)
- James Gana
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
- Department of Agricultural Education, School of Vocational Education, Federal College of Education, P.M.B. 39, Kontagora, Niger, Nigeria
| | - Nomakorinte Gcebe
- Bacteriology Department, Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria, South Africa
| | - Rebone Moerane
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
| | - Yusuf B. Ngoshe
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
| | - Khomotso Moabelo
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
| | - Abiodun A. Adesiyun
- Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
- School of Veterinary Medicine, Faculty of Medical Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago
| |
Collapse
|
2
|
Panwar S, Duggirala KS, Yadav P, Debnath N, Yadav AK, Kumar A. Advanced diagnostic methods for identification of bacterial foodborne pathogens: contemporary and upcoming challenges. Crit Rev Biotechnol 2023; 43:982-1000. [PMID: 35994308 DOI: 10.1080/07388551.2022.2095253] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 06/09/2022] [Indexed: 11/03/2022]
Abstract
It is a public health imperative to have safe food and water across the population. Foodborne infections are one of the primary causes of sickness and mortality in both developed and developing countries. An estimated 100 million foodborne diseases and 120 000 foodborne illness-related fatalities occur each year in India. Several factors affect foodborne illness, such as improper farming methods, poor sanitary and hygienic conditions at all levels of the food supply chain, the lack of preventative measures in the food processing industry, the misuse of food additives, as well as improper storage and handling. In addition, chemical and microbiological combinations also play a key role in disease development. But recent disease outbreaks indicated that microbial pathogens played a major role in the development of foodborne diseases. Therefore, prompt, rapid, and accurate detection of high-risk food pathogens is extremely vital to warrant the safety of the food items. Conventional approaches for identifying foodborne pathogens are labor-intensive and cumbersome. As a result, a range of technologies for the rapid detection of foodborne bacterial pathogens have been developed. Presently, many methods are available for the instantaneous detection, identification, and monitoring of foodborne pathogens, such as nucleic acid-based methods, biosensor-based methods, and immunological-based methods. The goal of this review is to provide a complete evaluation of several existing and emerging strategies for detecting food-borne pathogens. Furthermore, this review outlines innovative methodologies and their uses in food testing, along with their existing limits and future possibilities in the detection of live pathogens in food.
Collapse
Affiliation(s)
- Surbhi Panwar
- Department of Genetics and Plant Breeding, Chaudhary Charan Singh University, Meerut, India
| | | | - Pooja Yadav
- Centre for Molecular Biology, Central University of Jammu, Jammu, India
| | - Nabendu Debnath
- Centre for Molecular Biology, Central University of Jammu, Jammu, India
| | - Ashok Kumar Yadav
- Centre for Molecular Biology, Central University of Jammu, Jammu, India
| | - Ashwani Kumar
- Department of Nutrition Biology, Central University of Haryana, Mahendergarh, India
| |
Collapse
|
3
|
Rajkhowa S, Sonowal J, Borthakur U, Pegu SR, Deb R, Das PJ, Sengar GS, Gupta VK. Meta-Analysis of the Prevalence of Porcine Zoonotic Bacterial Pathogens in India: A 13-Year (2010-2023) Study. Pathogens 2023; 12:1266. [PMID: 37887783 PMCID: PMC10610365 DOI: 10.3390/pathogens12101266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 10/28/2023] Open
Abstract
The presence of bacterial pathogens such as Brucella spp., Clostridium spp., E. coli, Listeria monocytogenes, Salmonella spp., Staphylococcus spp., and Streptococcus suis not only hampers pig production but also carries significant zoonotic implications. The present study aims to conduct a comprehensive meta-analysis spanning over 13 years (2010-2023) to ascertain the prevalence of these zoonotic bacterial pathogens in Indian pig populations. The study seeks to synthesize data from diverse geographic regions within India and underscores the relevance of the One Health framework. A systematic search of electronic databases was meticulously performed. Inclusion criteria encompassed studies detailing zoonotic bacterial pathogen prevalence in pigs within India during the specified timeframe. Pertinent information including authors, publication year, geographical location, sampling techniques, sample sizes, and pathogen-positive case counts were meticulously extracted. The meta-analysis of zoonotic bacterial pathogens in Indian pig populations (2010-2023) unveiled varying prevalence rates: 9% Brucella spp., 22% Clostridium spp., 19% E. coli, 12% Listeria monocytogenes, 10% Salmonella spp. and Streptococcus suis, and 24% Staphylococcus spp. The application of random effects further revealed additional variability: 6% Brucella spp., 23% Clostridium spp., 24% E. coli, 14% Listeria monocytogenes, 10% Salmonella spp. and Streptococcus suis, and 35% Staphylococcus spp. Notably, the observed heterogeneity (I2) varied significantly from 87% to 99%. The meta-analysis findings underscore the pervasive nature of these diseases throughout India's pig populations, accentuating the substantial impact of these pathogens on pig health and the potential for zoonotic transmission. The present study reinforces the importance of the adoption of a comprehensive One Health approach that acknowledges the intricate interplay between animal, human and environmental health.
Collapse
Affiliation(s)
- Swaraj Rajkhowa
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Joyshikh Sonowal
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Udipta Borthakur
- Animal Husbandry and Veterinary Department, Guwahati 781003, Assam, India;
| | - Seema Rani Pegu
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Rajib Deb
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Pranab Jyoti Das
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Gyanendra Singh Sengar
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| | - Vivek Kumar Gupta
- ICAR-National Research Centre on Pig, Rani, Guwahati 781131, Assam, India; (J.S.); (S.R.P.); (R.D.); (P.J.D.); (G.S.S.); (V.K.G.)
| |
Collapse
|
4
|
Gume B, Berhanu L, Kassa T, Bediru H, Fikre AG, Dadi LS, Mereta ST. Bacterial hazard identification and exposure assessment of raw milk consumption in Jimma zone, South West Ethiopia. BMC Microbiol 2023; 23:166. [PMID: 37312070 PMCID: PMC10262534 DOI: 10.1186/s12866-023-02910-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 05/25/2023] [Indexed: 06/15/2023] Open
Abstract
BACKGROUND Raw milk may contain pathogenic microorganism that can sometimes fatally affect the health of consumers. However, risks related to raw milk consumption in Southwest Ethiopia are not well studied. The aim of this study was to evaluate the presence of five target pathogenic bacteria including Escherichia coli O157:H7, Salmonella enterica Typhimurium, Staphylococcus aureus, Listeria monocytogenes, and Campylobacter jejuni in raw milk and to assess exposure associated with the consumption of raw milk. METHOD A cross-sectional study was carried out between November 2019 and June 2020 to in Jimma zone, Southwest Ethiopia. Laboratory analysis was conducted on milk samples collected from Seven Woreda towns, including, Agaro, Yebu, Sekoru, Serbo, Shebe, Seka, Sheki and Jimma town administration. Semi-structured interview questions were administered to collect data on the amount and frequency of consumption. Descriptive statistics were used to summarize laboratory results and questionnaire survey data. RESULT Among 150 total raw milk samples, about 61.3% were found contaminated by one or more types of pathogens along the dairy value chain. The highest and the least bacterial counts recorded were 4.88 log10cfu/ml and 3.45 log10cfu/ml from E. coli and L. monocytogenes respectively. The mean concentrations of pathogens demonstrated significant statistical difference (p < 0.05) using 95% confidence interval where the prevalence percentage of isolates increased as the milk was transported from farms to the retail outlets. Except for C. jejuni; all other pathogens were detected in the range of unsatisfactory level of milk microbiological quality along the chain. The estimated mean annual risk of acquiring intoxication of E. coli across retailer outlets is 100% whereas salmonellosis, S. aureus intoxication, and listeriosis are 84%, 65% and 63% respectively. CONCLUSION The study highlights the significant health risks associated with the consumption of raw milk due to its unacceptable microbiological quality. The traditional production and consumption patterns of raw milk are the primary reasons for the high annual probability of infection. Therefore, regular monitoring and implementation of hazard identification and critical control point principles are necessary from raw milk production to retail points to ensure the safety of consumers.
Collapse
Affiliation(s)
- Beje Gume
- Department of Environmental Health Science and Technology, Jimma University, P.O. Box 378, Jimma, Ethiopia.
| | - Leykun Berhanu
- Department of Environmental Health Science, Wollo University, P.O. Box 1145, Dessie, Ethiopia
| | - Tesfaye Kassa
- School of Medical Laboratory Science, Jimma University, P.O. Box 788, Jimma, Ethiopia
| | - Habib Bediru
- Jimma Town Livestock and Fishery Development Office, P.O. Box 378, Jimma, Ethiopia
| | | | - Lelisa Sena Dadi
- Department of Epidemiology, Jimma University, P.O. Box 378, Jimma, Ethiopia
| | - Seid Tiku Mereta
- Department of Environmental Health Science and Technology, Jimma University, P.O. Box 378, Jimma, Ethiopia
| |
Collapse
|
5
|
Seakamela EM, Diseko L, Malatji D, Makhado L, Motau M, Jambwa K, Magwedere K, Ntushelo N, Matle I. Characterisation and antibiotic resistance of Yersinia enterocolitica from various meat categories, South Africa. Onderstepoort J Vet Res 2022; 89:e1-e11. [PMID: 36453823 PMCID: PMC9724029 DOI: 10.4102/ojvr.v89i1.2006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 07/18/2022] [Accepted: 08/17/2022] [Indexed: 10/29/2023] Open
Abstract
Yersinia enterocolitica infections impose a significant public health and socioeconomic burden on human population in many countries. The current study investigated the prevalence, antimicrobial resistance profile and molecular diversity of Y. enterocolitica in meat and meat products across various retail outlets in selected provinces of South Africa (SA). In a cross-sectional study, a total of 581 retail meat and meat products were collected from four cities across three provinces of SA. Samples were from beef and pork products, which included 292 raw intact, 167 raw processed, and 122 ready-to-eat (RTE) meats. Samples were analysed using classical microbiological methods for isolation, identification and biotyping of Y. enterocolitica. Conventional polymerase chain reaction (PCR) was performed for confirmation, serotyping, screening of virulence (n = 11) and antimicrobial resistance (n = 18) genes. Phenotypic antimicrobial resistance profiles were determined against 12 antibiotics discs, using disc diffusion method. The overall prevalence of 12% (70/581) was reported across all cities with contamination proportion reported in samples collected from raw intact 15% (43/292), followed by raw processed 11% (18/167) and RTE meats 7% (9/122). All positive isolates were of biotype 1A with 7% (5/70) belonging to bioserotype 1A/O:8. Most of the isolates harboured ymoA, ystB, fepD, ail, fepA, invA and myfA virulence genes. High antimicrobial resistance frequency was observed for ampicillin (94%), cephalothin (83%) and amoxicillin (41%), respectively. Of the 18 tested antimicrobial resistance genes, blaTEM was the most predominant (40%) followed by cmlA (21%). This study reveals the presence of antimicrobial resistant Y. enterocolitica possessing virulent genes of public health importance in products of animal origin, therefore, health monitoring and surveillance of this pathogen is required.
Collapse
Affiliation(s)
- Emmanuel M Seakamela
- Bacteriology Division, Onderstepoort Veterinary Research, Agricultural Research Council, Pretoria, South Africa; and, Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Pretoria.
| | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Zdolec N, Kiš M, Jankuloski D, Blagoevska K, Kazazić S, Pavlak M, Blagojević B, Antić D, Fredriksson-Ahomaa M, Pažin V. Prevalence and Persistence of Multidrug-Resistant Yersinia enterocolitica 4/O:3 in Tonsils of Slaughter Pigs from Different Housing Systems in Croatia. Foods 2022; 11:1459. [PMID: 35627029 PMCID: PMC9140555 DOI: 10.3390/foods11101459] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 01/18/2023] Open
Abstract
Yersinia enterocolitica is one of the priority biological hazards in pork inspection. Persistence of the pathogen, including strains resistant to antimicrobials, should be evaluated in pigs from different housing systems for risk ranking of farms. In this 2019 study, tonsils were collected from 234 pigs, of which 69 (29.5%) were fattened on 3 big integrated farms, 130 (55.5%) on 10 medium-sized farms, and 35 (15%) on 13 small family farms. In addition, 92 pork cuts and minced meat samples from the same farms were tested for the presence of Y. enterocolitica using the culture method. Phenotypic and genetic characteristics of the isolates were compared with previously collected isolates from 2014. The overall prevalence of Y. enterocolitica in pig tonsils was 43% [95% CI 36.7−49.7]. In pigs from big integrated, medium-sized, and small family farms, the prevalence was 29%, 52%, and 40%, respectively. All retail samples of portioned and minced pork tested negative for pathogenic Y. enterocolitica, likely due to high hygienic standards in slaughterhouses/cutting meat or low sensitivity of culture methods in these matrices. The highest recovery rate of the pathogen from tonsils was found when alkali-treated PSB and CIN agar were combined. The biosecurity category of integrated and medium farms did not affect the differences in prevalence of Y. enterocolitica (p > 0.05), in contrast to family farms. Pathogenic ail-positive Y. enterocolitica biotype 4 serotype O:3 persisted in the tonsils of pigs regardless of the type of farm, slaughterhouse, and year of isolation 2014 and 2019. PFGE typing revealed the high genetic concordance (80.6 to 100%) of all the Y. enterocolitica 4/O:3 isolates. A statistically significant higher prevalence of multidrug-resistant Y. enterocolitica 4/O:3 isolates was detected in the tonsils of pigs from big integrated farms compared to the other farm types (p < 0.05), with predominant and increasing resistance to nalidixic acid, chloramphenicol, and streptomycin. This study demonstrated multidrug resistance of the pathogen in pigs likely due to more antimicrobial pressure on big farms, with intriguing resistance to some clinically relevant antimicrobials used in the treatment of yersiniosis in humans.
Collapse
Affiliation(s)
- Nevijo Zdolec
- Faculty of Veterinary Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.K.); (M.P.); (V.P.)
| | - Marta Kiš
- Faculty of Veterinary Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.K.); (M.P.); (V.P.)
| | - Dean Jankuloski
- Faculty of Veterinary Medicine, Food Institute, 1000 Skopje, North Macedonia; (D.J.); (K.B.)
| | - Katerina Blagoevska
- Faculty of Veterinary Medicine, Food Institute, 1000 Skopje, North Macedonia; (D.J.); (K.B.)
| | | | - Marina Pavlak
- Faculty of Veterinary Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.K.); (M.P.); (V.P.)
| | - Bojan Blagojević
- Faculty of Agriculture, Department of Veterinary Medicine, University of Novi Sad, 21000 Novi Sad, Serbia;
| | - Dragan Antić
- Faculty of Health and Life Sciences, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Leahurst, Neston CH64 7TE, UK;
| | | | - Valerij Pažin
- Faculty of Veterinary Medicine, University of Zagreb, 10000 Zagreb, Croatia; (M.K.); (M.P.); (V.P.)
| |
Collapse
|
7
|
Aćimović M, Šovljanski O, Šeregelj V, Pezo L, Zheljazkov VD, Ljujić J, Tomić A, Ćetković G, Čanadanović-Brunet J, Miljković A, Vujisić L. Chemical Composition, Antioxidant, and Antimicrobial Activity of Dracocephalum moldavica L. Essential Oil and Hydrolate. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11070941. [PMID: 35406925 PMCID: PMC9002726 DOI: 10.3390/plants11070941] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 05/12/2023]
Abstract
Steam distillation was used for the isolation of Dracocephalum moldavica L. (Moldavian dragonhead) essential oil (DMEO). This aromatic herbaceous plant is widespread across the Northern Hemisphere regions and has been utilized in health-improving studies and applications. In addition to the DMEO, the hydrolate (DMH), a byproduct of the distillation process, was also collected. The DMEO and DMH were analyzed and compared in terms of their chemical composition, as well as their in vitro biological activities. The main component in DMEO was geranyl acetate, while geranial was dominant in DMH. The DMEO demonstrated better antioxidant and antimicrobial activities compared with the DMH against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes, which represent sources of food-borne illness at the global level. The DMEO and DMH show promise as antioxidant and antimicrobial additives to various products.
Collapse
Affiliation(s)
- Milica Aćimović
- Institute of Field and Vegetable Crops Novi Sad, Maksima Gorkog 30, 21000 Novi Sad, Serbia
- Correspondence:
| | - Olja Šovljanski
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (O.Š.); (V.Š.); (A.T.); (G.Ć.); (J.Č.-B.)
| | - Vanja Šeregelj
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (O.Š.); (V.Š.); (A.T.); (G.Ć.); (J.Č.-B.)
| | - Lato Pezo
- Institute of General and Physical Chemistry, Studentski trg 12-16, 11000 Belgrade, Serbia;
| | - Valtcho D. Zheljazkov
- College of Agricultural Sciences, Oregon State University, Corvallis, OR 97331, USA;
| | - Jovana Ljujić
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.L.); (L.V.)
| | - Ana Tomić
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (O.Š.); (V.Š.); (A.T.); (G.Ć.); (J.Č.-B.)
| | - Gordana Ćetković
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (O.Š.); (V.Š.); (A.T.); (G.Ć.); (J.Č.-B.)
| | - Jasna Čanadanović-Brunet
- Faculty of Technology, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (O.Š.); (V.Š.); (A.T.); (G.Ć.); (J.Č.-B.)
| | - Ana Miljković
- Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia;
| | - Ljubodrag Vujisić
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.L.); (L.V.)
| |
Collapse
|
8
|
Boukharouba A, González A, García-Ferrús M, Ferrús MA, Botella S. Simultaneous Detection of Four Main Foodborne Pathogens in Ready-to-Eat Food by Using a Simple and Rapid Multiplex PCR (mPCR) Assay. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19031031. [PMID: 35162055 PMCID: PMC8834630 DOI: 10.3390/ijerph19031031] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 12/25/2022]
Abstract
The increasing consumption of organic or ready-to-eat food may cause serious foodborne disease outbreaks. Developing microbiological culture for detection of food-borne pathogens is time-consuming, expensive, and laborious. Thus, alternative methods such as polymerase chain reaction (PCR) are usually employed for outbreaks investigation. In this work, we aimed to develop a rapid and simple protocol for the simultaneous detection of Escherichia coli (E coli), Listeria monocytogenes (L. monocytogenes), Staphylococcus aureus (S. aureus) and Salmonella enterica (S. enterica), by the combination of an enrichment step in a single culture broth and a multiplex PCR (mPCR) assay. The effectiveness of several enrichment media was assessed by culture and PCR. Buffered peptone water (BPW) was selected as the optimum one. Then, mPCR conditions were optimized and applied both to pure co-cultures and artificially inoculated food samples (organic lettuce and minced meat). In the culture medium inoculated at 100 CFU/mL, mPCR was able to detect the four microorganisms. When performed on artificially food samples, the mPCR assy was able to detect E. coli, S. enterica, and L. monocytogenes. In conclusion, BPW broth can effectively support the simultaneous growth of E. coli, S. aureus, L. monocytogenes, and S. enterica and could be, thus, used prior to a mPCR detection assay in ready-to-eat food, thereby considerably reducing the time, efforts and costs of analyzes.
Collapse
Affiliation(s)
| | | | | | | | - Salut Botella
- Correspondence: (M.A.F.); (S.B.); Tel.: +34-963877423 (M.A.F.)
| |
Collapse
|
9
|
Barbuddhe SB, Rawool DB, Doijad SP, Vergis J, Malik SS, Chakraborty T. Ecology of Listeria monocytogenes and Listeria species in India: the occurrence, resistance to biocides, genomic landscape and biocontrol. Environ Microbiol 2021; 24:2759-2780. [PMID: 34693631 DOI: 10.1111/1462-2920.15819] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 11/28/2022]
Abstract
Listeria monocytogenes, the causative agent of listeriosis, has been implicated in increasing foodborne outbreaks worldwide. The disease is manifested in various forms ranging from severe sepsis in immune-compromised individuals, febrile gastroenteritis, still birth, abortions and meningoencephalitis. In India, data from studies on the detection and molecular epidemiological analysis of L. monocytogenes are only recently emerging. The presence of Listeria in different ecological niches has been recorded from India, including foods, soil, vegetables, mangrove swamps, seafood, freshwater fishes, clinical cases, and also insects. The organism has also been isolated from women with spontaneous abortions, miscarriage or recurrent obstetric history, aborted foetuses, animal clinical cases and wildlife samples. A novel species of Listeria has also been characterized. Listeria monocytogenes strains isolated from clinical, environmental, and foods showed biofilm-forming abilities. Listeria monocytogenes serotype 4b isolates of ST328, a predominant and unique ST observed in India, was repeatedly isolated from different sources, times, and geographical locations. Here, we reviewed the occurrence of Listeria in different sources in India, its resistance to biocides, and provide epidemiological analysis on its genomic landscape.
Collapse
Affiliation(s)
| | - Deepak Bhiwa Rawool
- ICAR- National Research Centre on Meat, Chengicherla, Hyderabad, Telangana, 500092, India
| | - Swapnil Prakash Doijad
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, 35392, Germany.,German Center for Infection Research (DZIF), Giessen, 35392, Germany
| | - Jess Vergis
- Department of Veterinary Public Health, College of Veterinary and Animal Sciences, Pookode, Kerala Veterinary and Animal Sciences University, Wayanad, Kerala, 673576, India
| | - Satyaveer Singh Malik
- Division of Veterinary Public Health, ICAR- Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, 243122, India
| | - Trinad Chakraborty
- Institute for Medical Microbiology, Justus-Liebig University, Giessen, 35392, Germany.,German Center for Infection Research (DZIF), Giessen, 35392, Germany
| |
Collapse
|
10
|
Rajaei M, Moosavy MH, Gharajalar SN, Khatibi SA. Antibiotic resistance in the pathogenic foodborne bacteria isolated from raw kebab and hamburger: phenotypic and genotypic study. BMC Microbiol 2021; 21:272. [PMID: 34615465 PMCID: PMC8495966 DOI: 10.1186/s12866-021-02326-8] [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: 12/15/2020] [Accepted: 09/27/2021] [Indexed: 11/10/2022] Open
Abstract
Background In recent years, interest in the consumption of ready-to-eat (RTE) food products has been increased in many countries. However, RTE products particularly those prepared by meat may be potential vehicles of antibiotic-resistance foodborne pathogens. Considering kebab and hamburger are the most popular RTE meat products in Iran, this study aimed to investigate the prevalence and antimicrobial resistance of common foodborne pathogens (Escherichia coli, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes) in raw kebab and hamburger samples collected from fast-food centers and restaurants. Therefore, total bacterial count (TBC), as well as the prevalence rates and antibiogram patterns of foodborne pathogens in the samples were investigated. Also, the presence of antibiotic-resistance genes (blaSHV, blaTEM,blaZ, and mecA) was studied in the isolates by PCR. Results The mean value of TBC in raw kebab and hamburger samples was 6.72 ± 0.68 log CFU/g and 6.64 ± 0.66 log CFU/g, respectively. E. coli had the highest prevalence rate among the investigated pathogenic bacteria in kebab (70%) and hamburger samples (48%). Salmonella spp., L. monocytogenes, and S. aureus were also recovered from 58, 50, and 36% of kebab samples, respectively. The contamination of hamburger samples was detected to S. aureus (22%), L. monocytogenes (22%), and Salmonella spp. (10%). In the antimicrobial susceptibility tests, all isolates exhibited high rates of antibiotic resistance, particularly against amoxicillin, penicillin, and cefalexin (79.66–100%). The blaTEM was the most common resistant gene in the isolates of E. coli (52.54%) and Salmonella spp. (44.11%). Fourteen isolates (23.72%) of E. coli and 10 isolates (29.41%) of Salmonella spp. were positive for blaSHV. Also, 16 isolates (55.17%) of S. aureus and 10 isolates (27.27%) of L. monocytogenes were positive for mecA gene. Conclusions The findings of this study showed that raw kebab and hamburger are potential carriers of antibiotic-resistance pathogenic bacteria, which can be a serious threat to public health. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02326-8.
Collapse
Affiliation(s)
- Maryam Rajaei
- Department of Food Hygiene and Aquatic, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Mir-Hassan Moosavy
- Department of Food Hygiene and Aquatic, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
| | - Sahar Nouri Gharajalar
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Seyed Amin Khatibi
- Department of Food Hygiene and Aquatic, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| |
Collapse
|
11
|
Mortazavi SMH, Kaur M, Farahnaky A, Torley PJ, Osborn AM. The pathogenic and spoilage bacteria associated with red meat and application of different approaches of high CO 2 packaging to extend product shelf-life. Crit Rev Food Sci Nutr 2021; 63:1733-1754. [PMID: 34445909 DOI: 10.1080/10408398.2021.1968336] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
With the fast-global development of packaging techniques, the potential antimicrobial effect of CO2, as a safe, cheap and readily available gas, makes it the integral component for packaging of meat products. The associated spoilage and/or pathogenic bacteria on raw meat may respond in different ways to elevated CO2 concentrations. The growth of some aerobic Gram-negative bacteria such as Pseudomonas spp. is significantly inhibited but some LAB bacteria may be allowed to grow faster and dominate the product. The antimicrobial efficacy of enriched CO2 packaging is attributed to the rate of CO2 solubility in the product which is itself affected by the level of headspace CO2, product pH, temperature and the ratio of headspace gas to product (G:P). This review, first, explores the varied range of beef and sheep meat spoilage and pathogenic bacteria and the intrinsic and extrinsic parameters that may influence the pattern of microbial growth and meat spoilage rate during storage. Then, the antimicrobial mechanism of elevated CO2 packaging will be discussed and the different approaches of achieving enriched CO2 packaging i.e. the traditional technique of flushing a desired gas mixture and/or using the new commercially developed CO2 emitters will then be compared in terms of their strengths, limitations and technical mode of action.
Collapse
Affiliation(s)
| | - Mandeep Kaur
- Biosciences and Food Technology Discipline, School of Science, RMIT University, Melbourne, Australia
| | - Asgar Farahnaky
- Biosciences and Food Technology Discipline, School of Science, RMIT University, Melbourne, Australia
| | - Peter J Torley
- Biosciences and Food Technology Discipline, School of Science, RMIT University, Melbourne, Australia
| | - A Mark Osborn
- Biosciences and Food Technology Discipline, School of Science, RMIT University, Melbourne, Australia
| |
Collapse
|
12
|
Liu Y, Cui Y, Peng W, Huang B, Ma L, Zheng M, Ding S, Zhu K. Prevalence of pathogens harbouring mobile antimicrobial resistance genes and virulence factors in retail beef and mutton. FEMS Microbiol Lett 2021; 367:5854535. [PMID: 32510554 DOI: 10.1093/femsle/fnaa089] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 06/06/2020] [Indexed: 12/14/2022] Open
Abstract
Food safety is always a global issue, due to the increased dissemination of antimicrobial resistance and food poisoning related to foodborne bacterial pathogens. The purpose of this study was to assess the risk of potential foodborne bacteria of beef and mutton in retail stores. A total of 134 samples were collected from 24 local markets in Beijing, including raw and cooked beef or mutton, as well as samples derived from the corresponding environment and human beings. We obtained 674 isolates, of which Klebsiella spp. and Staphylococcus spp. were the dominant bacterial species in the meat samples and the environmental samples, respectively. Additionally, environmental bacteria are common in samples from different sources. Based on the results of antimicrobial sensitivity testing, resistance to tetracycline (with a resistance rate of 47.40%), amoxicillin + clavulanate (47.13%) and erythromycin (28.03%) were the major resistant phenotypes. According to the whole genome analysis, the extended spectrum beta-lactamase genes harboured by two K. pneumoniae strains isolated from cooked and raw beef were located on mobile elements. The major toxin genes of Bacillus cereus and adhesion- or invasion-related virulence factors were also shared among isolates from different sources. These factors pose potential risks to public health and need attention.
Collapse
Affiliation(s)
- Ying Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yifang Cui
- Institute of Animal Science and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Beijing 100097, China
| | - Wenjing Peng
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Baoyong Huang
- Beijing Municipal Station of Agro-Environment Monitoring, Beijing 100026, China
| | - Lichao Ma
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Min Zheng
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Shuangyang Ding
- National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Kui Zhu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.,National Center for Veterinary Drug Safety Evaluation, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety and Beijing Laboratory for Food Quality and Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| |
Collapse
|
13
|
Meat Safety from Farm to Slaughter—Risk-Based Control of Yersinia enterocolitica and Toxoplasma gondii. Processes (Basel) 2021. [DOI: 10.3390/pr9050815] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The implementation of the traditional meat safety control system has significantly contributed to increasing food safety and public health protection. However, several biological hazards have emerged in meat production, requiring a comprehensive approach to their control, as traditional methods of meat inspection at the slaughterhouse are not able to detect them. While national control programs exist for the most important meat-related hazards, similar data are still lacking for certain neglected threats, such as Yersinia enterocolitica or Toxoplasma gondii. The obstacle in controlling these hazards in the meat chain is their presence in latently infected, asymptomatic animals. Their effective control can only be achieved through systematic preventive measures, surveillance or monitoring, and antimicrobial interventions on farms and in slaughterhouses. To establish such a system, it is important to collect all relevant data on hazard-related epidemiological indicators from the meat chain, which should provide relevant guidance for interventions at the harvest and post-harvest stage. The proposed approach is expected to improve the existing system and provide many opportunities to improve food safety and public health.
Collapse
|
14
|
Ngo HHT, Nguyen-Thanh L, Pham-Duc P, Dang-Xuan S, Le-Thi H, Denis-Robichaud J, Nguyen-Viet H, Le TTH, Grace D, Unger F. Microbial contamination and associated risk factors in retailed pork from key value chains in Northern Vietnam. Int J Food Microbiol 2021; 346:109163. [PMID: 33798966 DOI: 10.1016/j.ijfoodmicro.2021.109163] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 02/04/2021] [Accepted: 03/07/2021] [Indexed: 11/30/2022]
Abstract
Pork and pork products are important staple food in the diet of Vietnamese consumers. The safety of pork, including biological contamination, is a concern to several public authorities and value chain actors. This cross-sectional study aimed to identify Salmonella and total bacterial count (TBC) contamination of cut pork sold in different outlets, and determine the potential factors leading to contamination. A total of 671 pork samples were collected from different retail channels in three provinces in Northern Vietnam. Hygiene conditions and practices at pork vending premises were also observed and recorded. Data analysis used descriptive statistics and regression analysis. Overall, Salmonella prevalence in retailed pork was 58.1%. Salmonella contamination in pork from traditional retail, modern retail and food services were 60.5%, 50.9% and 80.5%, respectively. Eighty percent and 68% of fresh pork in canteen and street food was contaminated with Salmonella. Only a small proportion of a subset of the pork samples (6.2%) tested met the Vietnamese standard requirement for TBC contamination. Average concentration of TBC in fresh pork in traditional retail, modern retail and food services were 6.51 (SD: 0.64), 6.38 (0.65), and 6.96 (0.85) LogCFU/g, respectively. Transport time, use of the same tools for pork and other types of meat, storage temperature, and environment hygiene are important factors that might affect microbial contamination. The findings underline the high level of microbial contamination, which requires practical interventions to improve food safety hygiene practices and behavior of pork retailers.
Collapse
Affiliation(s)
- Hai Hoang Tuan Ngo
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam; Department of Women's and Children's Health, Uppsala Global Health Research on Implementation and Sustainability, Uppsala University, Uppsala, Sweden.
| | - Luong Nguyen-Thanh
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam; University of Liege, Liege 4000, Belgium
| | - Phuc Pham-Duc
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam
| | - Sinh Dang-Xuan
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam; International Livestock Research Institute, Hanoi, Viet Nam
| | - Hang Le-Thi
- Center for Public Health and Ecosystem Research, Hanoi University of Public Health, Hanoi, Viet Nam
| | | | | | - Trang T H Le
- International Livestock Research Institute, Hanoi, Viet Nam
| | - Delia Grace
- International Livestock Research Institute, Nairobi, Kenya; Natural Resource Institute, University of Greenwich, Kent ME4 4TB, United Kingdom
| | - Fred Unger
- International Livestock Research Institute, Hanoi, Viet Nam
| |
Collapse
|
15
|
Morka K, Wałecka-Zacharska E, Schubert J, Dudek B, Woźniak-Biel A, Kuczkowski M, Wieliczko A, Bystroń J, Bania J, Bugla-Płoskońska G. Genetic Diversity and Distribution of Virulence-Associated Genes in Y. enterocolitica and Y. enterocolitica-Like Isolates from Humans and Animals in Poland. Pathogens 2021; 10:65. [PMID: 33450948 PMCID: PMC7828411 DOI: 10.3390/pathogens10010065] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/03/2021] [Accepted: 01/10/2021] [Indexed: 11/17/2022] Open
Abstract
Yersinia enterocolitica, widespread within domestic and wild-living animals, is a foodborne pathogen causing yersiniosis. The goal of this study was to assess a genetic similarity of Y. enterocolitica and Y. enterocolitica-like strains isolated from different hosts using Multiple Locus Variable-Number Tandem Repeat Analysis (MLVA) and Pulsed-Field Gel Electrophoresis (PFGE) methods, and analyze the prevalence of virulence genes using multiplex-Polymerase Chain Reaction (PCR) assays. Among 51 Yersinia sp. strains 20 virulotypes were determined. The most common virulence genes were ymoA, ureC, inv, myfA, and yst. Yersinia sp. strains had genes which may contribute to the bacterial invasion and colonization of the intestines as well as survival in serum. One wild boar Y. enterocolitica 1A strain possessed ail gene implying the possible pathogenicity of 1A biotype. Wild boar strains, represented mainly by 1A biotype, were not classified into the predominant Variable-Number Tandem Repeats (VNTR)/PFGE profile and virulotype. There was a clustering tendency among VNTR/PFGE profiles of pig origin, 4/O:3, and virulence profile. Pig and human strains formed the most related group, characterized by ~80% of genetic similarity what suggest the role of pigs as a potential source of infection for the pork consumers.
Collapse
Affiliation(s)
- Katarzyna Morka
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wrocław, Poland; (E.W.-Z.); (J.S.); (J.B.); (J.B.)
| | - Ewa Wałecka-Zacharska
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wrocław, Poland; (E.W.-Z.); (J.S.); (J.B.); (J.B.)
| | - Justyna Schubert
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wrocław, Poland; (E.W.-Z.); (J.S.); (J.B.); (J.B.)
| | - Bartłomiej Dudek
- Department of Microbiology, Institute of Genetics and Microbiology, Wroclaw University, S. Przybyszewskiego 63, 51-148 Wrocław, Poland;
| | - Anna Woźniak-Biel
- Department of Epizootiology and Clinic of Birds and Exotic Animals, Wrocław University of Environmental and Life Sciences, pl. Grunwaldzki 45, 50-366 Wrocław, Poland; (A.W.-B.); (M.K.); (A.W.)
| | - Maciej Kuczkowski
- Department of Epizootiology and Clinic of Birds and Exotic Animals, Wrocław University of Environmental and Life Sciences, pl. Grunwaldzki 45, 50-366 Wrocław, Poland; (A.W.-B.); (M.K.); (A.W.)
| | - Alina Wieliczko
- Department of Epizootiology and Clinic of Birds and Exotic Animals, Wrocław University of Environmental and Life Sciences, pl. Grunwaldzki 45, 50-366 Wrocław, Poland; (A.W.-B.); (M.K.); (A.W.)
| | - Jarosław Bystroń
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wrocław, Poland; (E.W.-Z.); (J.S.); (J.B.); (J.B.)
| | - Jacek Bania
- Department of Food Hygiene and Consumer Health Protection, Wrocław University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wrocław, Poland; (E.W.-Z.); (J.S.); (J.B.); (J.B.)
| | - Gabriela Bugla-Płoskońska
- Department of Microbiology, Institute of Genetics and Microbiology, Wroclaw University, S. Przybyszewskiego 63, 51-148 Wrocław, Poland;
| |
Collapse
|
16
|
Beccalli MP, Picozzi C, Mangieri N, Vigentini I, Foschino R. Assessment of Microbial Populations in the Manufacture of Vacuum-Packaged Ready-to-Eat Roast Beef and in a Related Production Plant. J Food Prot 2019; 82:58-64. [PMID: 30707054 DOI: 10.4315/0362-028x.jfp-18-147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Some microbiological criteria were monitored for 6 months in vacuum-packaged roast beef (15 production batches), raw beef (10 batches), and other meat products (12 batches) produced in an Italian small to medium-size enterprise. Fifty-five environmental swab samples also were analyzed. The main bacterial groups were identified by cultural methods according to International Organization for Standardization standards. Listeria monocytogenes was enumerated with the most-probable-number protocol, and species identification was confirmed with a specific PCR assay. Immediately after vacuum packaging, all ready-to-eat (RTE) products had low mean aerobic colony counts (<102 to 2.4 × 102 CFU g-1), anaerobic colony counts (1.6 to 6.5 × 101 CFU g-1), Enterobacteriaceae counts (1.1 to 1.4 × 101 CFU g-1), and Escherichia coli counts (generally below the detection limit). Nevertheless, the prevalence of L. monocytogenes in these samples was 3.7%. In roast beef samples, the aerobic and anaerobic colony counts reached unacceptable levels (>106 CFU g-1) after 14 days of refrigerated storage. Because the prevalence of L. monocytogenes increased to 13.3% during storage, a substantial reduction in the shelf life of these products is recommended. Surfaces without direct contact with food (floors and drains) had the highest mean counts for aerobic colonies (8.0 × 103 to 9.5 × 105 CFU/cm2), anaerobic colonies (2.9 × 103 to 3.2 × 104 CFU/cm2), Enterobacteriaceae (1.5 × 101 to 8.4 × 101 CFU/cm2), and E. coli (6.0 to 7.7 CFU/cm2). The levels of L. monocytogenes on direct food contact surfaces were below the detection limit, but more than 25% of floor samples were contaminated. These results reveal the persistence of L. monocytogenes in food processing environments, although at very low levels, posing a high risk of postcooking recontamination for RTE products. To improve hygienic conditions and reduce cross-contamination, an increase in operator awareness and a reassessment of surface sanitization protocols are needed.
Collapse
Affiliation(s)
- Matteo Paolo Beccalli
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, 2-20133 Milan, Italy (ORCID: http://orcid.org/0000-0003-3937-5355 [R.F.])
| | - Claudia Picozzi
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, 2-20133 Milan, Italy (ORCID: http://orcid.org/0000-0003-3937-5355 [R.F.])
| | - Nicola Mangieri
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, 2-20133 Milan, Italy (ORCID: http://orcid.org/0000-0003-3937-5355 [R.F.])
| | - Ileana Vigentini
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, 2-20133 Milan, Italy (ORCID: http://orcid.org/0000-0003-3937-5355 [R.F.])
| | - Roberto Foschino
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, 2-20133 Milan, Italy (ORCID: http://orcid.org/0000-0003-3937-5355 [R.F.])
| |
Collapse
|
17
|
A new single-tube platform of melting temperature curve analysis based on multiplex real-time PCR using EvaGreen for simultaneous screening detection of Shiga toxin-producing Escherichia coli, Salmonella spp. and Listeria monocytogenes in food. Food Control 2018. [DOI: 10.1016/j.foodcont.2018.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|