International journal of food microbiology最新文献

{"title":"Application of a novel lytic phage to control enterotoxigenic Escherichia coli in dairy food matrices","authors":"Madhvi Chahar ,&nbsp;Anuj Rana ,&nbsp;Vinay Kumar Gupta ,&nbsp;Anu Singh ,&nbsp;Namita Singh","doi":"10.1016/j.ijfoodmicro.2024.110924","DOIUrl":"10.1016/j.ijfoodmicro.2024.110924","url":null,"abstract":"<div><div>A novel <em>Escherichia coli</em> phage designated as EC BD was isolated from cattle dung samples. Transmission electron microscopy demonstrated that the morphology of phage EC BD belongs to the family Myoviridae. The efficiency of plating (EOP) and scanning electron microscopy revealed the strong lytic activity of phage EC BD with a large burst size and a short latent period. Whole genome data analysis suggested that phage EC BD was inclined towards being completely lytic and revealed the absence of toxins, virulence and antibiotic resistance genes. Phylogenomic analysis of phage EC BD receptor binding proteins (RBPs) showed 74–100 % similarity with sixteen Enterobacter phages, representing their broad host range. The phage genome contains 262 ORFs, of which 107 displayed a unique pattern and additionally, the presence of a tRNA gene directed their fast replication and high stability. Comparative genome analysis suggested phage EC BD as a novel member of the genus <em>Duplodnaviria</em> and family Myoviridae. The efficiency of phage EC BD was determined in dairy food matrices (milk, cheese and paneer) artificially contaminated with enterotoxigenic <em>E. coli</em> strains ETEC H10407, ETEC K 12S and ETEC PB 176 with a significant reduction of 4.8, 6.0 and 5.3 log CFU/mL in milk and a substantial 4.9, 5.8 and 4.6 log CFU/mL reduction in cheese samples after 6 days at low storage temperature (4 °C); furthermore, within the similar conditions, paneer samples showed 4, 5.1 and 3.5 log CFU/mL reduction. EC BD phage treatment represents the complete eradication of three ETEC strains in liquid and semisolid dairy food matrices. This study suggested that phage EC BD might have potential as a biocontrol approach against ETEC foodborne infections.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110924"},"PeriodicalIF":5.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346239","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":"Catalogue of surface proteins of Lactiplantibacillus plantarum strains of dairy and vegetable niches","authors":"Maria Fiorella Mazzeo ,&nbsp;Alida Sorrentino ,&nbsp;Stefano Morandi ,&nbsp;Houssam Abouloifa ,&nbsp;Abdeslam Asehraou ,&nbsp;Milena Brasca ,&nbsp;Rosa Anna Siciliano","doi":"10.1016/j.ijfoodmicro.2024.110922","DOIUrl":"10.1016/j.ijfoodmicro.2024.110922","url":null,"abstract":"<div><div><em>Lactiplantibacillus plantarum</em> (formerly <em>Lactobacillus plantarum</em>) exhibits relevant probiotic and technological features and is widely used in food industries, improving flavour, texture and organoleptic properties of fermented products. Cell-surface proteins have a key role in the molecular mechanisms responsible for healthy effects, being the first actors in the bacteria - host interactions. Proteins present on the surface of four <em>L. plantarum</em> strains (two isolated from vegetable matrices and two from dairy products) were identified by proteomics with the aim to gain a comprehensive picture of differences in protein profiles potentially related to the habitat of origin and specific properties of the analyzed strains. Results highlighted a more diversified pattern of surface proteins in strains from vegetable matrices compared to those from dairy matrices (&gt;500 proteins <em>vs</em> about 200 proteins, respectively). The four strains shared a core of 143 proteins, while 445 were specifically present in strains from vegetable matrices and 26 were peculiar of strains from dairy origin. Sortase A, involved in adhesion, and choloylglycine hydrolase (bile salt hydrolase) were detected only in strains from vegetable matrices. The peculiar molecular functions of identified proteins suggested that these strains, and in particular <em>L. plantarum</em> S61, could have a significant probiotic and biotechnological potential.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110922"},"PeriodicalIF":5.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel high-level phenyllactic acid fungal producer, Kodamaea ohmeri w5 screened from fermented broad bean-chili-paste","authors":"Chi Zhao ,&nbsp;Petri Penttinen ,&nbsp;Lingzi Zhang ,&nbsp;Ling Dong ,&nbsp;Fengju Zhang ,&nbsp;Decong Liao ,&nbsp;Suyi Zhang ,&nbsp;Zhihua Li ,&nbsp;Xiaoping Zhang","doi":"10.1016/j.ijfoodmicro.2024.110923","DOIUrl":"10.1016/j.ijfoodmicro.2024.110923","url":null,"abstract":"<div><div>Phenyllactic acid (PLA) is a broad-spectrum and efficient antimicrobial phenolic acid with potential applications in the food industry. Previous studies have demonstrated that fungi may be ideal producers of PLA. In this study, 15 fungi screened from Doubanjiang with the ability to produce PLA were first reported, including <em>Wickerhamomyces anomalus</em>, <em>Candida etchellsii</em>, <em>Candida parasitosis</em>, <em>Pichia kudriavzevii</em>, <em>Pichia membranifaciens</em> and <em>Kodamaea ohmeri</em>. Among them, <em>K. ohmeri</em> w5 had the highest PLA yield, producing up to 7160 mg/L PLA in shake flask fermentation with phenylalanine as substrate, which was more than ten times higher than the PLA produced by wild-type LAB under the similar conditions. In addition, <em>K. ohmeri</em> w5 was able to grow under extreme hypertonic conditions of 20 % NaCl (<em>w</em>/<em>v</em>) and 50 % glucose (w/v) as well as produce 57.12 ± 0.42 and 1609.22 ± 36.26 mg/L of PLA, respectively. Furthermore, the fermentation supernatant of <em>K. ohmeri</em> w5 demonstrated direct inhibitory effects against foodborne pathogenic microorganisms, <em>Aspergillus flavus</em> and <em>Bacillus cereus</em>. However, the inhibitory effect was weaker than that of the PLA standard at the same concentration. Further, 12,497,932 bp of w5 genome-wide information was obtained by sequencing and assembling. And its gene model was predicted based on transcriptomic evidence, which showed that a total of 7 genes related to PLA synthesis were identified in the w5 genome. Based on qRT-PCR, structure prediction, and molecular docking, a potentially key genetic resource from <em>K. ohmeri</em> w5 for PLA production was uncovered. The results will provide novel producers of PLA and its potential genetic resources.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110923"},"PeriodicalIF":5.0,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358709","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":"The exploration of pasteurization processes and mechanisms of inactivation of Bacillus cereus ATCC 14579 using radio frequency energy","authors":"Yanan Sun ,&nbsp;Yiming Jia ,&nbsp;Ke Wang ,&nbsp;Songlei Wang ,&nbsp;Baozhong Cui ,&nbsp;Chao Mao ,&nbsp;Xiaoying Guo ,&nbsp;Yuxin Feng ,&nbsp;Hongfei Fu ,&nbsp;Xiangwei Chen ,&nbsp;Yequn Wang ,&nbsp;Zhenna Zhang ,&nbsp;Yunyang Wang","doi":"10.1016/j.ijfoodmicro.2024.110919","DOIUrl":"10.1016/j.ijfoodmicro.2024.110919","url":null,"abstract":"<div><div>Radio frequency (RF) heating has been utilized to investigate sterilization techniques, but the mechanism of sterilization via RF heating, particularly on <em>Bacillus cereus</em> (<em>B. cereus</em>), has not been thoroughly examined. In this paper, sterilization processes and potential bactericidal mechanisms of <em>B. cereus</em> using RF were investigated. The best heating and sterilization efficiency was achieved at (Electrode gap 130 mm, conductivity of bacterial suspension 0.1 S/m, volume of bacterial suspension 40 mL). Heating a suspension of <em>B. cereus</em> to 90 °C in 80 s using RF reduced the number of viable bacteria by 4.87 logarithms. At the cellular level, there was a significant leakage of nucleic acids and proteins from the bacterial cells. Additionally, the integrity of the cell membrane was severely damaged, with a decrease in ATP concentration of 2.08 mM, Na, K-ATPase activity to 10.7 (U/10⁹ cells), and Ca, Mg-ATPase activity to 11.6 (U/10⁹ cells). At the molecular level, transcriptomics analysis showed that RF heating of <em>B. cereus</em> to 65 °C produced 650 more differentially expressed genes (DEGs) compared with RF heating to 45 °C. The GO annotation analysis indicated that the majority of differentially expressed genes (DEGs) were predominantly associated with cellular components. KEGG metabolic analysis showed enrichment in microbial metabolism in diverse environments, etc. This study investigated the potential bactericidal mechanism of <em>B. cereus</em> using RF, and provided some theoretical basis for the research of the sterilization of <em>B. cereus</em>.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110919"},"PeriodicalIF":5.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315183","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":"Post-acidification of fermented milk and its molecular regulatory mechanism","authors":"Yuxuan Guan ,&nbsp;Yanhua Cui ,&nbsp;Xiaojun Qu ,&nbsp;Baolei Li ,&nbsp;Lanwei Zhang","doi":"10.1016/j.ijfoodmicro.2024.110920","DOIUrl":"10.1016/j.ijfoodmicro.2024.110920","url":null,"abstract":"<div><div>The fermented milk products with lactic acid bacteria (LAB) are widely accepted by consumers. During the chilled-chain transportation and storage, LAB in the product keep producing lactic acid, and this will lead to post-acidification, which can affect the flavor, consumer acceptance and even shelf-life of the product. LAB is the determining factor affecting post-acidification. The acid production pathway in LAB and methods inhibiting post-acidification received widespread attention. This review will focus on the post-acidification from the perspective of fermentation starters, including acid production pathway in LAB, main factors and key enzymes affecting post-acidification. <em>Lactobacillus delbrueckii</em> subsp. <em>bulgaricus</em> is a key bacterial species responsible for post acidification in the fermented milk products. The different species and strains presented various differences in process like acid production, acid resistance and post-acidification. Furthermore, multiple factors, such as milk composition, fermentation temperature, and homogenization, also can influence post-acidification. Lactose transport and utilization pathways, as well as its subsequent products metabolic pathway directly influence the post-acidification. F₀F₁-ATPase, β-galactosidase, and lactate dehydrogenase are recognized as important enzymes related to post-acidification. The degree of post-acidification is mainly related to the acid production and acid resistance abilities of the fermentation starters, so the key enzymes related to post-acidification are mostly taking part in these two capacities. Recently, some new post-acidification related biomarker genes were found, providing a reference adjusting post-acidification without affecting fermentation rate and bacteria viability. To clarify the post-acidification mechanism at the molecular level will help control post- acidification.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110920"},"PeriodicalIF":5.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310479","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":"Novel insights into biofilm formation and the key differentially expressed genes in Yersinia enterocolitica from meat: Implications for food safety and disease prevention","authors":"Xiuqin Lou ,&nbsp;Yue Wu ,&nbsp;Zongzong Chen ,&nbsp;Qian Zhang ,&nbsp;Xiao Xiao ,&nbsp;Zhiguo Fang","doi":"10.1016/j.ijfoodmicro.2024.110914","DOIUrl":"10.1016/j.ijfoodmicro.2024.110914","url":null,"abstract":"<div><p><em>Yersinia enterocolitica</em> is an important foodborne pathogen that can cause a zoonotic disease known as yersiniosis, which causes symptoms such as acute diarrhea, mesenteric adenitis, terminal ileum inflammation, pseudo appendicitis, sepsis, and other complications. The mechanism of biofilm formation in <em>Y. enterocolitica</em> remains poorly understood, with limited research available on this topic. This study systematically examined the distribution characteristics and biofilm formation ability of <em>Y. enterocolitica</em> isolated from poultry and livestock related samples. Analysis of food samples collected indicated significant presence of <em>Y. enterocolitica</em> (207/670, 30.9 %), particularly in frozen duck meat (7/11, 63.6 %). Majority of the isolated strains did not demonstrate biofilm-forming ability (52.7 %), while a notable percentage exhibited moderate (6.8 %) to strong (11.6 %) biofilm-forming ability. Additionally, a significant percentage of strains (16/207, 7.7 %) displayed extremely high optical density/cut-off OD (OD/ODC) ratios (the average OD value of each sample divided by the average OD value of the negative controls of each 96-well plate plus 3 standard deviations) (exceeding 10). Time-course analysis of biofilm formation in 10 isolates revealed three distinct patterns: (i) rapid increase from 6 h to 12 h, with gradual peak between 48 and 72 h followed by a slight decline and stabilization; (ii) little biofilm formation at 24 h with a gradual increase up to 96 h, maintaining this level until 120 h; and (iii) complete absence of biofilm formation throughout the experiment. Subsequent examination of differentially expressed genes (DEGs) in planktonic cells and biofilms of two strains with distinct biofilm formation capabilities identified seven metabolic pathways, including ribosome, photosynthesis, fatty acid degradation, valine, leucine, and isoleucine degradation, as well as pinene, camphor, and geraniol degradation. Significantly elevated expression levels of genes associated with flagellar assembly, bacterial chemotaxis, and quorum sensing (partially) were observed exclusively in planktonic cells of the selected strain with stronger biofilm-forming ability, implying that the heightened expression of flagellar assembly and bacterial chemotaxis-related genes is an important but not sole determinant of biofilm formation. The study contributes to the elucidation of the underlying mechanisms governing biofilm formation in <em>Y. enterocolitica</em> and may offer valuable insights for the advancement of novel food safety strategies.</p></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110914"},"PeriodicalIF":5.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142272163","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":"Salmonella in black pepper (Piper nigrum): From farm to processing","authors":"Mariana Barboza Vinha ,&nbsp;Larissa Bernardino Moro ,&nbsp;Inorbert de Melo Lima ,&nbsp;Maristela da Silva do Nascimento ,&nbsp;Giovanna Pinto Pires ,&nbsp;Jairo Pinto de Oliveira ,&nbsp;Servio Tulio Alves Cassini","doi":"10.1016/j.ijfoodmicro.2024.110921","DOIUrl":"10.1016/j.ijfoodmicro.2024.110921","url":null,"abstract":"<div><div>Contamination of black pepper (<em>Piper nigrum</em>) with <em>Salmonella</em> is a frequent problem in retail and imported shipments. However, there is scarce information about the prevalence of the pathogen in the initial stages of black pepper production chain. This study sought to bridge this gap in research by determining the prevalence, as well as quantifying, and identifying the main <em>Salmonella</em> serovars present during black pepper primary production and processing. Black pepper (233) and environmental (175) samples were collected from farms (354) and processing plants (54) in Espirito Santo, Brazil. The pathogen was detected in soil (16.7 %), drying waste (20.4 %), fallen berries (3.7 %), threshed berries (14.3 %), and dried peppercorns (22.2 %) collected from farms. <em>Salmonella</em> was also detected in samples of raw material (11.1 %), export products (16.7 %), and processing waste (16.7 %) collected from processing plants. A total of 12 serotypes were identified, and <em>Salmonella</em> Javiana showed the highest prevalence (38.8 %). According to the results, contamination occurring in the post-harvest phase is not eliminated or reduced during processing. Therefore, the adoption of good agricultural and manufacturing practices, supported by hazard analysis and critical control points (HACCP), is crucial to mitigate this kind of contamination. These practices should be combined with decontamination treatments to ensure the safety of the final product.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110921"},"PeriodicalIF":5.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322983","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":"An atoxigenic Aspergillus flavus PA67 from Shandong province exhibits potential in biocontrol against toxigenic Aspergillus flavus, Sclerotium rolfsii, and Fusarium proliferatum","authors":"Jia Xu ,&nbsp;Yanyan Zhang ,&nbsp;Junhe Ren,&nbsp;Qing Kong","doi":"10.1016/j.ijfoodmicro.2024.110918","DOIUrl":"10.1016/j.ijfoodmicro.2024.110918","url":null,"abstract":"<div><p>Peanuts and corn are susceptible to various soil-borne fungi, leading to significant economic losses. Atoxigenic <em>Aspergillus flavus</em> have been widely used as biocontrol agents for managing aflatoxin contamination because of their minimal environmental impact, strong competitive ability, and sustained inhibition effect. After multiple identifications and cluster amplification pattern (CAP) analysis, three atoxigenic <em>A. flavus</em> PA04, PA10 and PA67 were isolated from peanut samples in Shandong Province, which can reduce aflatoxin levels by up to 90 %. Our study revealed that atoxigenic <em>A. flavus</em> also competed vigorously with <em>Sclerotium rolfsii</em> and <em>Fusarium proliferatum</em> for nutrition and space, achieving notable inhibition rates of up to 90.4 % and 90.6 %, respectively. The supernatants of atoxigenic <em>A. flavus</em> also inhibited the growth of <em>S. rolfsii</em> and <em>F. proliferatum</em>, with PA67 demonstrating the most significant effect. Whole genome sequencing revealed that PA67 contains multiple glycoside hydrolases and metabolites with antifungal activity. The kojic acid production of PA67 was higher than that of PA04 and PA10, reaching 17.48 g/L, which has a significant inhibition on sclerotia germination. PA67 supernatant significantly inhibited the hyphae growth of <em>S. rolfsii</em> and <em>F. proliferatum</em>, and down-regulated genes related to sclerotia and fumonisin formation. This study demonstrates the biocontrol potential of PA67 against three soil-borne fungi and is the first investigation of atoxigenic <em>A. flavus</em> to inhibit <em>S. rolfsii</em> and <em>F. proliferatum</em>.</p></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110918"},"PeriodicalIF":5.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238374","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":"Microbial decontamination of fresh-cut celery using simultaneous ultrasound and plasma-activated water treatment.","authors":"Sohee Yoon, Hye Won Lee, Ji-Yeong Jessica Bak, Sea C Min","doi":"10.1016/j.ijfoodmicro.2024.110912","DOIUrl":"https://doi.org/10.1016/j.ijfoodmicro.2024.110912","url":null,"abstract":"<p><p>This study investigated an ultrasound (US) treatment strategy in plasma-activated water (PAW) (UP treatment) to inactivate indigenous aerobic bacteria, Escherichia coli O157:H7, and Listeria monocytogenes in fresh-cut celery. Both plasma discharge and US treatment times contributed to the inactivation of indigenous bacteria in celery. The predicted optimal UP treatment conditions included a discharge time of 61.5 min and treatment time of 338 s, resulting in the inactivation of indigenous bacteria, E. coli O157:H7, and L. monocytogenes by 2.7, 1.7, and 3.2 log CFU/g, respectively. With an increase in plasma discharge time or US treatment time, the oxidation-reduction potential and electrical conductivity values of PAW increased, while the pH decreased. UP treatment effectively inactivated bacteria non-thermally, without altering the color of celery. Furthermore, UP treatment led to an increase in cell lipid peroxidation, reactive oxygen species production, and the number of non-viable E. coli O157:H7 and L. monocytogenes cells with membrane damage. This study highlights the potential of UP treatment for bacterial decontamination of fresh-cut celery.</p>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":" ","pages":"110912"},"PeriodicalIF":5.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346238","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":"Inhibitory effect and mechanism of violacein on planktonic growth, spore germination, biofilm formation and toxin production of Bacillus cereus and its application in grass carp preservation","authors":"Xiangdi Lou ,&nbsp;Qiang Zhou ,&nbsp;Qiyue Jiang ,&nbsp;Liping Lin ,&nbsp;Wenwu Zhu ,&nbsp;Xiaoyu Mei ,&nbsp;Jianhua Xiong ,&nbsp;Yanyan Gao","doi":"10.1016/j.ijfoodmicro.2024.110917","DOIUrl":"10.1016/j.ijfoodmicro.2024.110917","url":null,"abstract":"<div><p><em>Bacillus cereus</em> is a ubiquitous foodborne pathogen commonly found in various foods. Its ability to form spores, biofilms and diarrhoeal and/or emetic toxins further exacerbates the risk of food poisoning. Violacein is a tryptophan derivative with excellent antibacterial activity. However, the knowledge on the antibacterial action of violacein against <em>B. cereus</em> was lacking, and thus this study aimed to investigate the antibacterial activity and mechanism. The antibacterial results demonstrated that minimum inhibitory concentration and minimum bactericidal concentration of violacein were 3.125 mg/L and 12.50 mg/L, respectively. Violacein could effectively inhibit planktonic growth, spore germination and biofilm formation of <em>B. cereus</em> (<em>P</em> &lt; 0.001). Meanwhile, violacein significantly downregulated the expression of toxin genes, including <em>nheA</em> (<em>P</em> &lt; 0.05), <em>nheB</em> (<em>P</em> &lt; 0.001), <em>bceT</em> (<em>P</em> &lt; 0.01), <em>cytK</em> (P &lt; 0.001), <em>hblC</em> (P &lt; 0.001) and <em>hblD</em> (P &lt; 0.001). Results of extracellular alkaline phosphatase, nucleotide and protein leakage assays and scanning and transmission electron microscopy observation tests showed violacein destroyed cell walls and membranes of <em>B. cereus</em>. In addition, 6.25 mg/kg of violacein could significantly inhibit <em>B. cereus</em> in grass carp fillets (<em>P</em> &lt; 0.05). These results demonstrate that violacein has great potential as an effective natural antimicrobial preservative to control food contamination and poisoning events caused by <em>B. cereus</em>.</p></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110917"},"PeriodicalIF":5.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238372","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}