International journal of food microbiology最新文献

{"title":"Biocontrol mechanisms of antagonistic yeasts on postharvest fruits and vegetables and the approaches to enhance the biocontrol potential of antagonistic yeasts","authors":"Fangfang Wu ,&nbsp;Haibo Wang ,&nbsp;Yankun Lin ,&nbsp;Shun Feng ,&nbsp;Xinguo Li","doi":"10.1016/j.ijfoodmicro.2024.111038","DOIUrl":"10.1016/j.ijfoodmicro.2024.111038","url":null,"abstract":"<div><div>During storage and transportation, fruits and vegetables are susceptible to various pathogens, leading to quality degradation and significant economic losses. Currently, chemical pesticides are primarily used for control; however, their overuse poses serious threats to human health and causes environmental pollution. Biocontrol, known for its environmentally friendly characteristics, has been extensively studied. Among biocontrol agents, yeasts are widely distributed and possesses strong antagonistic abilities, making them crucial agents against numerous pathogenic fungi. Despite their considerable promise, the full potential of antagonistic yeasts for broader application remains untapped. Therefore, this paper reviews the mechanisms of antagonistic yeasts as biocontrol agents for postharvest diseases, including space and nutrients competition, competition for scarce iron resources, parasitism, production of soluble and volatile antifungal compounds, and induction of host systemic resistance. The paper also introduces research on the combined application of antagonistic yeasts with physical, chemical, and other microbial methods. Ultimately, this review provides a potential pathway to enhance the biocontrol effectiveness of antagonistic yeasts and expand their application prospects.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111038"},"PeriodicalIF":5.0,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142909649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of non-typhoidal Salmonella reveals the highly prevalent mcr-1-positive S. 1,4,[5],12:i:- within eggs are derived from chickens","authors":"Ting-Yu Yang ,&nbsp;Tiantian Liu ,&nbsp;Yan Li ,&nbsp;Zeqing Wang ,&nbsp;Meijun Chu ,&nbsp;Junjie Wang ,&nbsp;Ming Zou ,&nbsp;Bao-Tao Liu","doi":"10.1016/j.ijfoodmicro.2024.111048","DOIUrl":"10.1016/j.ijfoodmicro.2024.111048","url":null,"abstract":"&lt;div&gt;&lt;div&gt;&lt;em&gt;Salmonella&lt;/em&gt; is one of the most common foodborne pathogens. Antimicrobial-resistant &lt;em&gt;Salmonella&lt;/em&gt; isolates, especially those resistant to colistin, pose a significant threat to public health worldwide. However, data about the prevalence of &lt;em&gt;mcr&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; in animals was few and the dissemination of &lt;em&gt;mcr&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; from animals to food, especially eggs, has not been fully addressed. The role of houseflies in the &lt;em&gt;Salmonella&lt;/em&gt; transmission has also not been clarified. Here, we analyzed the prevalence and resistance characteristics of &lt;em&gt;mcr&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; in 1707 samples of animals (commercial laying hens, broilers, waterfowls and swine), eggs and flies from 23 farms in four cities of China between July 2021 and October 2022. Pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS) analyses of &lt;em&gt;Salmonella&lt;/em&gt; from different sources were further performed. Among animals, waterfowls had the highest isolation rate of &lt;em&gt;Salmonella&lt;/em&gt; (18.1 %, 35/193), followed by swine (6.1 %, 23/377), laying hens (4.2 %, 21/505) and broilers (1.4 %, 7/489). Two of the 53 flies (3.8 %) carried &lt;em&gt;Salmonella&lt;/em&gt;. The detection rate of &lt;em&gt;Salmonella&lt;/em&gt; in eggs from farms was 26.7 %. All &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; isolates were &lt;em&gt;S&lt;/em&gt;. 1,4,[5],12:i:- and were only found in hens (0.2 %) and eggs (11.1 %). PFGE and WGS analyses showed that the &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;S&lt;/em&gt;. 1,4,[5],12:i:- from commercial laying hens and eggs in the same farm had no single nucleotide polymorphism (SNP) variation, indicating that the &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;S&lt;/em&gt;. 1,4,[5],12:i:- in eggs were derived from hens. The phylogenomic analysis also showed that the &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;S&lt;/em&gt;. 1,4,[5],12:i:- isolates from hens and eggs were closely related to previously reported &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; from human in China, further confirming that such &lt;em&gt;mcr-1&lt;/em&gt;-positive &lt;em&gt;Salmonella&lt;/em&gt; in animals could transmit to humans via the food chain. Furthermore, the &lt;em&gt;bla&lt;/em&gt;&lt;sub&gt;CTX-M-1G&lt;/sub&gt;-positive &lt;em&gt;S&lt;/em&gt;. Kentucky isolates from broiler and flies in the same farm had a limited number of variations (5–7 SNPs), proving the clonal transmission of &lt;em&gt;Salmonella&lt;/em&gt; between broilers and flies. The &lt;em&gt;S&lt;/em&gt;. Kentucky isolates carrying &lt;em&gt;bla&lt;/em&gt;&lt;sub&gt;CTX-M-1G&lt;/sub&gt; from broilers were also closely related to the &lt;em&gt;S&lt;/em&gt;. Kentucky isolates from chicken meats and humans. Our findings suggest that &lt;em&gt;Salmonella&lt;/em&gt; including those carrying &lt;em&gt;mcr-1&lt;/em&gt; in animals could transmit to eggs/meats and potentially trigger human infections. The houseflies can play an important role in the &lt;em&gt;Salmonella&lt;/em&gt; transmission within farms. &lt;em&gt;Salmonella&lt;/em&gt; carrying &lt;em&gt;mcr&lt;/em&gt; in animals and animal products should be monitored regularly and control measures are urgently needed to reduce the dissemination of suc","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111048"},"PeriodicalIF":5.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of low-salt stress on biological characteristics and transcriptomic profiles of Vibrio parahaemolyticus","authors":"Zhiyong Song ,&nbsp;Lu Chen ,&nbsp;Shiying Tang ,&nbsp;Yingjie Pan ,&nbsp;Qingchao Xie ,&nbsp;Yong Zhao ,&nbsp;Haiquan Liu","doi":"10.1016/j.ijfoodmicro.2024.111047","DOIUrl":"10.1016/j.ijfoodmicro.2024.111047","url":null,"abstract":"<div><div>Studies have proved that halophilic <em>Vibrio parahaemolyticus</em> is widely detected in freshwater environments (salinity &lt;0.5 %). However, the growth and colonization of <em>V. parahaemolyticus</em> in low-salt environments remain unclear. This study was envisaged to assess the effects of low-salt stress on the growth, motility and biofilm formation of <em>V. parahaemolyticus</em> and the transcriptomic changes that the bacterium responds to such stress. The results indicated that low salt concentrations supported the growth (allowing growth to proceed, though at a lower speed) of <em>V. parahaemolyticus</em>, prolonged the lag time (LT), and decreased the maximum specific growth rate (<em>μ</em>_<em>max</em>) of <em>V. parahaemolyticus</em>. Additionally, this low salinity inhibited its motility and enhanced its biofilm formation capacity. Notably, the growth of <em>V. parahaemolyticus</em> on both freshwater and marine-cultured <em>Litopenaeus vannamei</em> exhibited a similar trend, suggesting that <em>V. parahaemolyticus</em> might have adapted to thrive in freshwater food. Furthermore, the reasons for the support of <em>V. parahaemolyticus</em> growth in 0.25 % NaCl was analyzed by transcriptome sequencing (RNA-seq). RNA-seq revealed that <em>V. parahaemolyticus</em> can improve resistance to adverse environments by reducing energy consumption and enhancing oxidative stress resistance to adapt to a low-salt environment. This study revealed that the freshwater environment supported the growth of <em>V. parahaemolyticus</em> and its influence on the growth of <em>V. parahaemolyticus</em>, providing valuable theoretical support for risk assessment.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111047"},"PeriodicalIF":5.0,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of dielectric-barrier discharge (DBD) cold plasma for control of bread spoilage fungi","authors":"Jéssica Gonçalves Lemos ,&nbsp;Lhwan Philippe Silva ,&nbsp;Mailah Ali Abdul Rahman Mahfouz ,&nbsp;Leonardo Alvarenga Freire Cazzuni ,&nbsp;Liliana Oliveira Rocha ,&nbsp;Caroline Joy Steel","doi":"10.1016/j.ijfoodmicro.2024.111034","DOIUrl":"10.1016/j.ijfoodmicro.2024.111034","url":null,"abstract":"<div><div>Bread is a greatly consumed bakery product worldwide. Unfortunately, it is an optimal substrate for fungal contamination and deterioration (aw &gt; 0.95), commonly caused by the genera <em>Penicillium, Paecilomyces</em>, and <em>Aspergillus,</em> resulting in significant economic losses. Traditional conservation methods, such as the use of calcium propionate, are rejected by some consumers, leading to investment in alternative methods, such as the use of cold plasma. This study aimed to verify the effectiveness of dielectric-barrier discharge (DBD) cold plasma in inhibiting the growth of bread spoilage fungi. The species <em>Penicillium sumatrense</em> (ML1), <em>Penicillium roqueforti</em> (FML125), <em>Penicillium paneum</em> (FML126), <em>Paecilomyces variotii</em> (FML112), <em>Aspergillus niger</em> (ML2) were used. To assess the effect of plasma on fungi, they were inoculated into swabs, stainless steel coupons, and then small plugs were taken directly from the fungal culture and pan bread slices. All strains were inoculated into swabs and pan bread slices, but only the ML1 strain was used for experiments with coupons and plugs. Regarding the swabs of all strains (System I, 50 W/15 min), in addition to the milder treatments on the plug (System II, 50 W/2.5, 5, 10, and 20 min) and all treatments of ML1 strain coupons (System II, 200 W/15 min, 10 W and 8 W/2.5 and 1.5 min), the cold plasma presented fungistatic properties, delaying mycelial growth from 8 to 30 days and reducing the fungal population by 2.24 log when compared to controls. By analyzing the 200 W treatment with the longest exposure (5, 10, and 20 min) on the plug, plasma showed fungicidal action, completely inactivating mycelial growth. Regarding the pan bread slices, plasma System III, when applied for 45 min, reduced strains FML126 and FML112 by 1 log, FML125 and ML2 by 2 logs, and ML1 by 7 logs, demonstrating potential for use as a control method in the baking industry.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111034"},"PeriodicalIF":5.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fungi associated with orange juice production and assessment of adhesion ability and resistance to sanitizers","authors":"Larissa Pereira Margalho ,&nbsp;Camila Siedlarczyk Martins ,&nbsp;Naara Aparecida Almeida ,&nbsp;Juliana Carusi ,&nbsp;Mailah Ali Abdul Rahman Mahfouz ,&nbsp;Anderson S. Sant'Ana ,&nbsp;Maristela Silva Nascimento ,&nbsp;Liliana de Oliveira Rocha","doi":"10.1016/j.ijfoodmicro.2024.111035","DOIUrl":"10.1016/j.ijfoodmicro.2024.111035","url":null,"abstract":"<div><div>Orange juice is widely consumed worldwide due to its sensory and nutritional characteristics. This beverage is susceptible to contamination by acidic-tolerant microorganisms due to its low pH, especially filamentous fungi and yeasts. To minimize fungal spoilage, companies usually submit juice to thermal treatments; sanitizers are also applied on surfaces to maintain the microbiological quality. This study aimed to identify potential contamination sources in a juice processing line and to verify the susceptibility of isolated yeasts and filamentous fungi to food-grade sanitizers. Also, their ability to form single and binary adherent cells was assessed. The results revealed the presence of fungi in all samplings performed, with the most prominent microorganisms identified as <em>Paecilomyces variotii</em>, <em>P. paravariotii</em>, <em>Pichia kudriavzevii</em> and <em>Wickerhamomyces anomalus</em>. After obtaining results for sanitizer resistance and adhesion ability of the isolates, these were submitted to multivariate analysis using hierarchical cluster analysis (HCA), and two groups were found: one composed mostly of filamentous fungi (16/18) with low adhesion potential and one group formed by yeasts with high adhesion ability and resistance to sanitizers. Microscopy images corroborate those data, demonstrating the importance of yeast cell agglomerates along germinated spores of filamentous fungi and the importance of adhered biomass to protect cells against the sanitizers tested. This study is the first to combine fungi isolated from a beverage processing line and aims to contribute to the current knowledge of fungal adhesion and sanitizer resistance.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111035"},"PeriodicalIF":5.0,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Untargeted metabolomics to relate changes produced by biocontrol agents against Aspergillus westerdijkiae and Penicillium nordicum in vitro on dry-cured ham","authors":"Eva Cebrián ,&nbsp;Elia Roncero ,&nbsp;João Luz ,&nbsp;Marta Sousa Silva ,&nbsp;Carlos Cordeiro ,&nbsp;Ana Belén Peromingo ,&nbsp;Mar Rodríguez ,&nbsp;Félix Núñez","doi":"10.1016/j.ijfoodmicro.2024.111036","DOIUrl":"10.1016/j.ijfoodmicro.2024.111036","url":null,"abstract":"<div><div>Dry-cured ham is a highly appreciated meat product. During the ripening, moulds grow on its surface such as <em>Penicillium nordicum</em> and <em>Aspergillus westerdijkiae</em> producers of ochratoxin A (OTA). This mycotoxin poses a risk to consumers that must be controlled. The aim of this work is to evaluate the effectiveness of <em>Debaryomyces hansenii</em> and <em>Staphylococcus xylosus</em> isolated from dry-cured ham as a combined biocontrol culture (BCA) to reduce the OTA produced by one strain of <em>A. westerdijkiae</em> and two strain of <em>P. nordicum</em>, and to assess the metabolomic changes they cause. Each mould was inoculated alone and in combination with BCA on dry-cured ham for 14 days at 20 °C. OTA and total metabolites were analysed in a mass spectrometer Orbitrap Q- Exactive Plus. The Compound Discoverer software, in-house Python-based software and the Metaboanalyst software were used for metabolite analysis. BCA reduced the OTA of <em>A. westerdijkiae</em>, <em>P. nordicum</em> 15 and <em>P. nordicum</em> 856 by 78 %, 99 % and 65 % respectively. BCA caused changes in their metabolome, mainly in the phenylalanine metabolism pathway altering compounds such as Phenylacetaldehyde, Phenylpyruvate or trans-2-hydroxycinnamate, the synthesis of phenylalanine, tyrosine, and tryptophan altering compounds such as 4-hydroxyphenylpyruvate or L-tryptophan, and in the synthesis of oxylipins derived from the linoleic acid metabolism such as 13-OxoODE, 9(<em>S</em>)-HODE or 9(10)-EpOME.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111036"},"PeriodicalIF":5.0,"publicationDate":"2024-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective control of snake fruit (Salacca zalacca) rot using Trichoderma asperelloides SKRU-01: A safe approach to preserving fruit quality","authors":"Sawai Boukaew ,&nbsp;Julalak Chuprom ,&nbsp;Jirayu Buatong ,&nbsp;Sujirat Sornprasit ,&nbsp;Sureeporn Wijitsopa ,&nbsp;Karistsapol Nooprom ,&nbsp;Rachasak Boonhok","doi":"10.1016/j.ijfoodmicro.2024.111037","DOIUrl":"10.1016/j.ijfoodmicro.2024.111037","url":null,"abstract":"<div><div>Rot disease, caused by the fungal pathogen <em>Peniophora salaccae</em> SKRU002, affects the quality of snake fruit production. In the pursuit of sustainable disease management, biocontrol using <em>Trichoderma asperelloides</em> SKRU-01 offers a promising solution. This study evaluated the antagonistic potential of <em>T. asperelloides</em> SKRU-01 against <em>P. salaccae</em> SKRU002 in both <em>in vitro</em> assays and snake fruit trials, while also assessing its impact on fruit quality. <em>In vitro</em> dual culture assays revealed that <em>T. asperelloides</em> SKRU-01 inhibited <em>P. salaccae</em> SKRU002 growth by 62.5 % over 10 days through efficient nutrient colonization. Microscopic analysis confirmed that <em>T. asperelloides</em> SKRU-01 hyphae penetrated and wrapped around <em>P. salaccae</em> SKRU002, causing cytoplasmic lysis. Additionally, <em>T. asperelloides</em> SKRU-01 culture filtrates (20 % <em>v/v</em>) completely inhibited <em>P. salaccae</em> SKRU002 growth in both solid and liquid media. LC-QTOF/MS analysis identified 31 secondary metabolites, including toyocamycin and antimycin A1. In snake fruit trials, <em>T. asperelloides</em> SKRU-01 culture filtrates provided 100 % protection against disease incidence (DI) and severity (DS), comparable to Mancozeb®. The application of <em>T. asperelloides</em> SKRU-01 spores (10⁷ spores/mL) reduced DI and DS to 0 % within 1–3 days post-pathogen inoculation, demonstrating both protective and curative effects. Furthermore, while <em>P. salaccae</em> SKRU002 significantly affected fruit quality—causing weight loss, color changes, and reductions in total soluble solids, phenolic content, titratable acidity, and antioxidant activity—the simultaneous application of <em>T. asperelloides</em> SKRU-01 mitigated these effects without compromising fruit quality. These findings indicate the antagonistic activity of <em>T. asperelloides</em> SKRU-01 and its metabolites against <em>P. salaccae</em> SKRU002, suggesting their potential as biofungicidal agents for managing rot disease in snake fruit.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111037"},"PeriodicalIF":5.0,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Survey of foodborne pathogenic Vibrio species in commercial Tasmanian bivalve shellfish and predictors of risk at harvest","authors":"Valeria Anna Torok ,&nbsp;Khandaker Rayhan Mahbub ,&nbsp;Paul A. Grey ,&nbsp;Graham Clive Fletcher ,&nbsp;Alison R. Turnbull","doi":"10.1016/j.ijfoodmicro.2024.111033","DOIUrl":"10.1016/j.ijfoodmicro.2024.111033","url":null,"abstract":"&lt;div&gt;&lt;div&gt;There has been an increase in foodborne vibriosis outbreaks globally, with &lt;em&gt;Vibrio parahaemolyticus&lt;/em&gt; emerging as a foodborne issue in temperate commercial shellfish growing regions, including southern Australia. The food safety concerns associated with these microorganisms have led to the need for specific guidance on potential risk management strategies for their control. This is the first Australian multi-seasonal survey of &lt;em&gt;V. parahaemolyticus&lt;/em&gt; and &lt;em&gt;Vibrio vulnificus&lt;/em&gt; in commercial shellfish growing areas aimed at understanding their occurrence and regional environmental drivers of risk at harvest. Eleven commercial Tasmanian shellfish (oyster and mussel) growing areas were surveyed for the prevalence and levels of &lt;em&gt;V. parahaemolyticus&lt;/em&gt;, including presence of pathogenicity associated &lt;em&gt;tdh&lt;/em&gt; and &lt;em&gt;trh&lt;/em&gt; genes, and &lt;em&gt;V. vulnificus&lt;/em&gt; at harvest between 2020 and 2022. &lt;em&gt;Vibrio parahaemolyticus&lt;/em&gt; was detected in all surveyed growing areas during the three summer/autumn sampling periods, with a prevalence of 8–100 %. Prevalence was generally higher in the north (north-west, Moulting Bay and upper east coast) as compared with the mid-east coast and south-east and Bruny regions. &lt;em&gt;Vibrio parahaemolyticus&lt;/em&gt; was only detected in five of the eleven growing areas during the two surveyed winter/spring seasons: Duck Bay, Moulting Bay, Great Swanport, Little Swanport and Boomer Bay East. Where it was detected, the prevalence was much lower in the winter/spring seasons (17–33 %). Levels of &lt;em&gt;V. parahaemolyticus&lt;/em&gt; detected during the survey were generally low (&lt;10 MPN/g) for most growing areas. Some higher levels (100–1100 MPN/g) were observed in Duck Bay, Moulting Bay, Great Swanport and Little Swanport. Only one sample from Great Swanport had a level of over 1000 MPN/g (1,100 MPN/g). The higher levels were only observed in the summer/autumn sampling periods. &lt;em&gt;Vibrio parahaemolyticus tdh&lt;/em&gt;, &lt;em&gt;trh&lt;/em&gt; or &lt;em&gt;tdh&lt;/em&gt;/&lt;em&gt;trh&lt;/em&gt; gene detections only occurred in the summer/autumn months with a prevalence of 0–21 %, 0–18 % or 0–7 %, respectively, depending on the growing area surveyed. Despite low levels &lt;em&gt;of V. parahaemolyticus&lt;/em&gt; being detected in southern commercial growing areas, five sporadic cases of vibriosis associated with oysters from southern Tasmania were reported during the survey period, predominantly from oysters harvested recreationally. Levels of &lt;em&gt;V. vulnificus&lt;/em&gt; detected were generally very low in most Tasmanian growing areas (&lt;1 MPN/g). However, levels of 35–460 MPN/g were detected in shellfish at harvest in one area (Great Swanport). Predictive models for &lt;em&gt;V. parahaemolyticus&lt;/em&gt; at harvest were developed from survey data which were area specific. Water temperature was the sole or primary driver in most areas. Predictive models for &lt;em&gt;V. vulnificus&lt;/em&gt; at harvest were developed for Great Swanport and were driven by river flow and rainfall.&lt;/di","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111033"},"PeriodicalIF":5.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of novel mutations involved in the development of resistance to colistin in Salmonella isolates from retail pork in Shanghai, China","authors":"Zeqiang Zhan,&nbsp;Shoukui He,&nbsp;Jiang Chang,&nbsp;Mengjun Hu,&nbsp;Zengfeng Zhang,&nbsp;Yan Cui,&nbsp;Xianming Shi","doi":"10.1016/j.ijfoodmicro.2024.111027","DOIUrl":"10.1016/j.ijfoodmicro.2024.111027","url":null,"abstract":"<div><div><em>Salmonella</em> is an important foodborne pathogen that poses a significant threat to food safety. This study aims to assess the prevalence, genomic features, and colistin-resistant mechanisms of <em>Salmonella</em> isolates collected from 118 retail pork samples from January 2021 to January 2022 in Shanghai, China. Overall, 46 (39.0 %, 46/118) <em>Salmonella</em> isolates were collected, which were identified as 12 serotypes by genomic analysis, including <em>Salmonella Typhimurium</em> (<em>n</em> = 17) and <em>Salmonella</em> London (<em>n</em> = 6). Antimicrobial resistance profiling revealed that the resistance rate of these isolates to colistin was 13.0 % (6/46), while 60.9 % (28/46) exhibited multidrug-resistant. It was found that there were 51 distinct antimicrobial resistance genes in these 46 isolates, which were predominantly associated with resistance to aminoglycosides, fluoroquinolones, and β-lactams. More importantly, among six colistin-resistant isolates, two isolates (<em>Salmonella</em> Schwarzengrund and <em>Salmonella</em> Indiana) were found to carry the <em>mcr-1</em> gene. The mechanism of resistance in the remaining four colistin-resistant isolates was further studied, and it was found that there were nine amino acid substitutions in PmrAB. It was demonstrated by site-directed mutagenesis that novel substitutions G53W in PmrA and I83V in PmrB led to colistin resistance in <em>Salmonella</em> (MIC = 2 or 4 μg/mL). Analysis results by real-time quantitative PCR and mass spectrometry indicated that the mutants PmrA^G53W and PmrB^I83V displayed higher expression levels of the gene <em>pmrE</em> than in the parental strain. This upregulation resulted in an increase in the production of 4-amino-4-deoxy-l-arabinose (L-Ara4N) that modified lipid A, thereby conferring resistance to colistin. These findings demonstrated that there was a high prevalence of MDR <em>Salmonella</em> isolates in retail pork in Shanghai, and the substitution G53W in PmrA and I83V in PmrB were independent factors contributing to the development of resistance to colistin in <em>Salmonella</em> via modification of lipid A with L-Ara4N.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111027"},"PeriodicalIF":5.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of fusidic acid-resistant Staphylococcus aureus isolated from food animals during 2010–2021 in South Korea","authors":"Su-Jeong Kim ,&nbsp;Md. Sekendar Ali ,&nbsp;Hee-Seung Kang ,&nbsp;Bo-Youn Moon ,&nbsp;Yu-Jeong Hwang ,&nbsp;Soon-Seek Yoon ,&nbsp;Seung-Chun Park ,&nbsp;Suk-Kyung Lim","doi":"10.1016/j.ijfoodmicro.2024.111026","DOIUrl":"10.1016/j.ijfoodmicro.2024.111026","url":null,"abstract":"<div><div>Livestock-associated fusidic acid-resistant <em>Staphylococcus aureus</em> (FRSA) is frequently linked to global public health hazards. This study aimed to ascertain the prevalence and molecular characteristics of FRSA isolated from food animal products in South Korea from 2010 to 2021. We obtained a total of 3980 <em>S. aureus</em> isolates from cattle carcasses (n = 482), pig carcasses (n = 1531), and chicken carcasses (n = 1967). The isolates were evaluated for antimicrobial susceptibility using the broth microdilution method. Antimicrobial resistance genes, <em>spa</em> types, sequence types (STs), and <em>Staphylococcus</em> cassette chromosome <em>mec</em> (SCC<em>mec</em>) types were determined by polymerase chain reaction (PCR) and sequencing analysis. In total, 187 isolates (4.7 %) demonstrated resistance to fusidic acid, with the maximum recovered from cattle (16.2 %), followed by pigs (6.5 %) and chickens (0.5 %). In addition, the majority of the isolates showed resistance to penicillin (86.6 %), while comparatively low resistance rates (7–13.9 %) were observed for erythromycin, gentamicin, kanamycin, and tetracycline. Moreover, multidrug resistance (MDR) comprised 8.6 % (16/187) of the isolates. Among the fusidic acid resistance determinants, the <em>fusA</em> mutation was the highest, containing 54 % (101/187), followed by <em>fusC</em> (29.4 %, 55/187) and <em>fusB</em> (15.5 %, 29/187). A high level of resistance regarding the substitution of L461K in the <em>fusA</em> gene was identified in 97 % of isolates. In addition, the most commonly detected resistance patterns include penicillin (87.1 %, 88/101) among the FRSA. The nucleotide sequencing analysis showed that all 29 <em>fusB</em>-carrying isolates possess the structural gene <em>blaZ</em> of the <em>bla</em> operon and the insertion sequences <em>orf152</em>, <em>orf170</em>, IS<em>257</em>, and <em>orf152</em>. In total, 21 <em>spa</em> types were found, where t126 was detected the most (81.2 %, 82/101) in <em>fusA</em>, followed by t127 (81.8 %, 45/55) in <em>fusC</em>, and t189 (27.6 %, 8/29) in <em>fusB</em>. Furthermore, all t002 harboring <em>fusC</em> were detected as ST5-MRSA-SCC<em>mec</em>II clones. This is the first report of <em>fusA</em> and <em>fusB</em> carrying <em>S. aureus</em> and linkage <em>fusB</em> and <em>blaZ</em> genes in FRSA isolated from food animal products. Taken together, the FRSA in food animals with different resistance determinants and <em>spa</em> types could pose a threat to public health.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111026"},"PeriodicalIF":5.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}