International journal of food microbiology最新文献

{"title":"Revisiting secondary model features for describing the shoulder and lag parameters of microbial inactivation and growth models","authors":"Alberto Garre ,&nbsp;Vasilis Valdramidis ,&nbsp;Silvia Guillén","doi":"10.1016/j.ijfoodmicro.2025.111078","DOIUrl":"10.1016/j.ijfoodmicro.2025.111078","url":null,"abstract":"<div><div>The Baranyi and Geeraerd models are two of the most reliable models for the description of, respectively, microbial growth and inactivation. They are defined as a system of differential equations, whose algebraic solution can describe the microbial response during isothermal conditions, especially when combined with suitable secondary models. However, there are still large uncertainties regarding the best functions to use as secondary models for the lag phase duration (<em>λ</em>) and the shoulder length (<em>S</em>_<em>l</em>).</div><div>In this article, we revisit these models, focusing on the implications related to the assumption of an ideal substance whose dynamics define bacterial adaptation. We demonstrate that their link with the isothermal lag and shoulder leads to unique secondary models for the effect of temperature changes on <em>λ</em> and <em>S</em>_<em>l</em>. Namely, a log-linear relationship for <em>S</em>_<em>l</em> and a reverse cuadratic relationship for <em>λ</em> (considering a Ratkowsky model for <em>μ</em>). Furthermore, we observe a coupling between both secondary models (<em>k</em> and <em>S</em>_<em>l</em> for Geeraerd; <em>λ</em> and <em>μ</em> for Baranyi), reducing the number of unknown model parameters from four to three. Using data from the scientific literature, we illustrate the applicability of these results, being able to improve the robustness of parameter estimates.</div><div>The identification of these links are of great relevance for the field of predictive microbiology, as they resolve the uncertainty regarding the functional form of secondary models. Our results also provide a way to assess the validity of those dynamic hypotheses using data gathered under isothermal conditions, something that was hardly possible using data gathered under dynamic conditions. Although this study is limited to the effect of temperature, the general approach and methodology are also applicable to other type of secondary models, so this article can be a blueprint for future studies.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"431 ","pages":"Article 111078"},"PeriodicalIF":5.0,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143038442","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":"Effect of surface roughness on the efficacy of Plasma Activated Mist (PAM) for inactivation of Listeria innocua and Klebsiella michiganensis","authors":"Tejaswini Tumuluri ,&nbsp;Sumeyye Inanoglu ,&nbsp;Donald W. Schaffner,&nbsp;Mukund V. Karwe","doi":"10.1016/j.ijfoodmicro.2025.111070","DOIUrl":"10.1016/j.ijfoodmicro.2025.111070","url":null,"abstract":"<div><div>Cold plasma generated by dielectric barrier discharge (DBD) and DBD combined with nebulized liquid microdroplets to generate plasma-activated mist (PAM) have shown the potential as a surface decontamination method for the food industry. The objective of this research was to measure the microbial inactivation caused by DBD and by PAM on tryptic soy agar (TSA) and on glass slides and to determine the efficacy of PAM on selected surfaces having different surface topographies. Tryptic soy agar in Petri dishes and on glass slides (surface roughness Pq = 0.28 ± 0.02 μm) was inoculated with either 0.1 mL of inoculum containing <em>Listeria innocua</em> (8.4 ± 0.1 log CFU/mL) or <em>Klebsiella michiganensis</em> (8.8 ± 0.2 log CFU/mL) and exposed to either DBD or PAM for 5 to 20 min. Glass slides, grape tomatoes (Pq = 5.17 μm ± 0.53 μm), limes (Pq = 18.76 μm ± 3.00 μm), and spiny gourds (Pq = 101.50 μm ± 10.95 μm) were also surface-inoculated with <em>L. innocua</em> or <em>K. michiganensis</em> and exposed to PAM for 5 to 20 min. No significant difference in microbial inactivation was observed between DBD plasma and PAM for all treatment times. The smoothest surface (glass) showed the highest reduction in <em>L. innocua</em> (3.4 ± 0.2 log CFU/item) and <em>K. michiganensis</em> (5.7 ± 0.0 log CFU/item) after PAM treatment. The roughest surface (spiny gourd) yielded a significantly lower reduction for <em>L. innocua</em> (1.0 ± 0.2 log CFU/item) and <em>K. michiganensis</em> (1.8 ± 0.1 log CFU/item). <em>L. innocua</em> was less susceptible to inactivation by PAM compared <em>K. michiganensis</em>. This study highlighted the importance of surface roughness on microbial inactivation of <em>L. innocua</em> and <em>K. michiganensis</em> by DBD and PAM on produce surfaces.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"431 ","pages":"Article 111070"},"PeriodicalIF":5.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143038437","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":"Thymoquinone as a potent antimicrobial agent against Yersinia enterocolitica: Mechanisms of action and potential food safety applications","authors":"Hui Yang ,&nbsp;Shuqi Wang ,&nbsp;Pengyu Zhao ,&nbsp;Qiyao Yong ,&nbsp;Qianning Huang ,&nbsp;Fahad Al-Asmari ,&nbsp;Manal Y. Sameeh ,&nbsp;Baowei Yang ,&nbsp;Chunling Zhang ,&nbsp;Xin Wang ,&nbsp;Chao Shi","doi":"10.1016/j.ijfoodmicro.2025.111071","DOIUrl":"10.1016/j.ijfoodmicro.2025.111071","url":null,"abstract":"<div><div><em>Yersinia enterocolitica</em> (<em>Y. enterocolitica</em>) is a Gram-negative foodborne pathogen associated with potentially fatal diseases. Herein, the antibacterial activity and possible mechanism of thymoquinone (TQ) against <em>Y. enterocolitica</em> were explored. The minimum inhibitory concentration and the minimum bactericidal concentration of TQ against <em>Y. enterocolitica</em> were determined to be 0.10 and 0.20 mg/mL, respectively. Treatment with TQ increased the lag phase period and reduced the growth rate of <em>Y. enterocolitica</em>. TQ was also effective in preventing <em>Y. enterocolitica</em> contamination of pork. Treatment of <em>Y. enterocolitica</em> with TQ caused a decrease in intracellular ATP, membrane depolarization and an increase in the level of intracellular reactive oxygen species. In addition, TQ caused damage to DNA, a reduction in protein content, loss of membrane integrity and abnormal cell morphology. These findings suggest that TQ exhibits antimicrobial activity against <em>Y. enterocolitica</em> and may be a suitable compound to reduce <em>Y. enterocolitica</em> growth in food.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"431 ","pages":"Article 111071"},"PeriodicalIF":5.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143038443","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":"Spoilage characteristics of sous-vide beef caused by Clostridium estertheticum","authors":"Samart Dorn-In,&nbsp;Riem El-Seniti,&nbsp;Karin Schwaiger","doi":"10.1016/j.ijfoodmicro.2025.111069","DOIUrl":"10.1016/j.ijfoodmicro.2025.111069","url":null,"abstract":"<div><div>The increasing popularity of sous-vide (SV) cooking necessitates research into the microbiological quality, sensory changes, and shelf life of SV products. Studies show that SV cooking significantly reduces the levels of meat microbiota and pathogens, positively affecting the shelf life and safety of SV products. However, the meat spoilage organism <em>Clostridium estertheticum</em> can survive SV cooking as it can produce heat-tolerant spores. Theses spores can germinate and multiply during storage at refrigerated temperatures, leading to spoilage of SV meat. Therefore, the aim of this study was to characterise the spoilage of SV beef caused by <em>C. estertheticum</em> compared to non-SV beef. In addition to the determination of spoilage characteristics, all beef samples were subjected to culture and qPCR analysis to determine the numbers of total bacteria, lactic acid bacteria, <em>Enterobacteriaceae</em>, yeasts, and <em>C. estertheticum</em>. Species identification of the colonies on the culture media was performed using MALDI-TOF MS. The tests were carried out at three different times (three repetitions). A total of 90 beef samples were analysed, of which 54 samples were artificially contaminated with three strains of <em>C. estertheticum</em> and vacuum-packed. Of these, 27 beef samples underwent SV cooking (55 °C, 70 min). After 28 days of storage at 4 °C, the SV beef samples exhibited significantly higher levels of gas and stronger spoilage odour compared to non-SV samples (<em>p</em> &lt; 0.05). While drip loss and pH levels were also higher in SV beef, these were not considered specific spoilage characteristics caused by <em>C. estertheticum</em>. Microbiological and qPCR analyses revealed that all SV beef samples had very low bacterial and yeast counts but very high numbers of <em>C. estertheticum</em>, which strongly correlated with the sensory changes observed. We concluded that SV beef containing <em>C. estertheticum</em> has a shorter shelf life than contaminated non-SV beef. This is the first study to examine the spoilage of SV beef by <em>C. estertheticum</em>. The results may help raise awareness among meat producers and restaurants about the risk of meat losses due to spoilage caused by these bacteria.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111069"},"PeriodicalIF":5.0,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004737","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":"Imported seafood is a reservoir of Enterobacteriaceae carrying CTX-M-encoding genes of high clinical relevance","authors":"Ryan Pearce ,&nbsp;Mattia Pirolo ,&nbsp;Nicole B. Goecke ,&nbsp;Valeria Toppi ,&nbsp;Liam Good ,&nbsp;Javier Guitian ,&nbsp;Luca Guardabassi","doi":"10.1016/j.ijfoodmicro.2025.111063","DOIUrl":"10.1016/j.ijfoodmicro.2025.111063","url":null,"abstract":"<div><div>We determined the frequency, genotypes, phenotypes, and mobility of extended-spectrum β-lactamase (ESBL)-encoding genes in <em>Enterobacteriaceae</em> isolated from retail seafood products. Overall, 288 samples of fresh shrimps, catfish and seabass imported from Asia were collected from three supermarket chains in the UK (96 each). After enrichment in MacConkey broth supplemented with cefotaxime, total DNA was screened for the presence of CTX-M, SHV and TEM by real-time PCR. Positive samples were cultured on ESBL selective media and presumptive ESBL-producing isolates were confirmed by PCR and identified to the species level by MALDI-TOF-MS. CTX-M-positive isolates were further characterized by whole genome sequencing (WGS), antimicrobial susceptibility testing, and conjugation experiments. Approximately one in thirteen (7.6 %) seafood products were contaminated with ESBL-producing <em>Enterobacteriaceae</em>. WGS analysis revealed the presence of CTX-M-15 (<em>n</em> = 7), CTX-M-27 (n = 7), and CTX-M-55 (n = 7), CTX-M-14 (<em>n</em> = 4) among <em>Enterobacteriaceae</em> isolated from shrimp (<em>n</em> = 21) and catfish (n = 4), and FONA-6 in two <em>Serratia fonticola</em> isolates from seabass. The higher rate of contamination in shrimp could be due to post-harvest contamination due to human handling or washing practices during processing. Half (<em>n</em> = 13) of the CTX-M-producing isolates transferred <em>bla</em>_{<em>CTX-M</em>} to laboratory <em>E. coli</em> via IncA/C (<em>n</em> = 6), IncX2 (<em>n</em> = 4), IncFIIK (<em>n</em> = 1) or non-typeable plasmids (<em>n</em> = 2). All plasmids contained additional resistance genes conferring resistance to antimicrobials used in aquaculture, indicating possible co-selection through the use these antimicrobials. The frequent occurrence of CTX-M-encoding genes of high clinical relevance in imported seafood, particularly shrimp, often on transferrable plasmids, underscores the need for ESBL surveillance on traded seafood, alongside quantitative risk assessment studies aimed at evaluating the potential health risks for consumers who are exposed to these bacteria via consumption of raw seafood.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111063"},"PeriodicalIF":5.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004728","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":"Detection of aflatoxin B1 level and revelation of its dynamic accumulation process using visible/near-infrared hyperspectral and microscopic imaging","authors":"Xiaohuan Guo ,&nbsp;Wei Wang ,&nbsp;Beibei Jia ,&nbsp;Xinzhi Ni ,&nbsp;Hong Zhuang ,&nbsp;Seung-Chul Yoon ,&nbsp;Scott Gold ,&nbsp;Anthony Pokoo-Aikins ,&nbsp;Trevor Mitchell ,&nbsp;Brian Bowker ,&nbsp;Jiawei Ye","doi":"10.1016/j.ijfoodmicro.2025.111065","DOIUrl":"10.1016/j.ijfoodmicro.2025.111065","url":null,"abstract":"<div><div>Understanding and controlling the dynamic process of aflatoxin B₁ (AFB₁) accumulation by <em>Aspergillus flavus</em> (<em>A. flavus</em>) remains challenging. In this study, the <em>A. flavus</em> development and AFB₁ accumulation were investigated using visible/near-infrared (Vis/NIR) hyperspectral imaging (HSI) on culture media, Potato Dextrose Agar (PDA), PDA + <span>l</span>-glutamine (Gln), and PDA + rapamycin (RAPA). In addition, the levels of AFB₁ in various heterogeneous regions of colonies were measured and their microscopic morphology was characterized. In the temporal and spatial domains, fungal colonies exhibited a concentric circular response pattern. A continuous increase in AFB₁ content was observed in the PDA and PDA + Gln groups as culture time increased. The growth of <em>A. flavus</em> and aflatoxin accumulation were promoted by adding Gln to PDA. However, adding RAPA inhibited the development of fungi and the production of AFB₁. The distribution of AFB₁ across the fungal colony was uneven, and this heterogeneity was associated with the aging and autolysis of the hyphae. Principal component analysis showed that spectral bands of 480, 623, 674, 726 nm were related to the color changes of hyphae and spores during colony growth; however, wavelengths of 840, 882, 867, 972 nm were key bands related to changes in nutritional composition. Multiple preprocessing techniques and modeling methods employed to construct regression models for predicting AFB₁ contents showed that the first-derivative and partial least squares regression (PLSR) provided the best results. A visualization map of AFB₁ levels established using the optimal model showed a spatial pattern similar to the measurement results. This study highlights the application potential of Vis/NIR HSI for monitoring <em>A. flavus</em> growth and AFB₁ content.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"431 ","pages":"Article 111065"},"PeriodicalIF":5.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143038436","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":"A novel method of species-specific molecular target mining and accurate discrimination of Bacillus cereus sensu lato","authors":"Yibing Zhao ,&nbsp;Jihang Xie ,&nbsp;Shubo Yu ,&nbsp;Qingping Wu ,&nbsp;Zhi Wang ,&nbsp;Yuting Shang ,&nbsp;Zhengzheng Wang ,&nbsp;Jumei Zhang ,&nbsp;Huichan Zhai ,&nbsp;Zhenying Huang ,&nbsp;Yu Ding ,&nbsp;Juan Wang","doi":"10.1016/j.ijfoodmicro.2025.111068","DOIUrl":"10.1016/j.ijfoodmicro.2025.111068","url":null,"abstract":"<div><div><em>Bacillus cereus</em>, a member of the <em>Bacillus cereus sensu lato</em> (<em>B. cereus s.l.</em>), is widely distributed in nature and can contaminate a variety of foods, leading to foodborne illnesses and substantial losses in the food industry. Although culture-based methods remain the gold standard for identifying <em>B. cereus</em> due to their high sensitivity under specific conditions, they are often complex and labor-intensive to implement. Furthermore, the high genetic similarity among certain members of the <em>B. cereus s.l.</em> makes it challenging to identify species-specific molecular targets, hindering the rapid and accurate differentiation of these bacteria. In this study, we introduce a novel method, comparative analysis based on whole genome slices (CAWGS), combined with the Basic Local Alignment Search Tool (BLAST) for efficient molecular target mining. Using CAWGS-BLAST and pan-genome analysis, we successfully identified new molecular targets for <em>B. cereus</em>, <em>Bacillus thuringiensis</em>, emetic <em>B. cereus</em>, <em>Bacillus anthracis</em>, <em>Bacillus mycoides</em>, <em>Bacillus weihenstephanensis</em>, and <em>Bacillus megaterium</em>. Based on these newly discovered targets, we developed a PCR-CRISPR/Cas12a method for detecting <em>B. cereus s.l.</em> and related species. Our research not only provides a rapid and accurate approach for discriminating <em>B. cereus s.l.</em> and related species, but also offers a universal and valuable reference for detecting foodborne pathogens, especially those with highly similar phenotypic and genetic characteristics.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"431 ","pages":"Article 111068"},"PeriodicalIF":5.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143023408","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":"Virulence expression difference to intestinal cells of different pathogenic Listeria monocytogenes contaminating sausages after simulated digestive tract","authors":"Cong Zhou ,&nbsp;Yafang Zou ,&nbsp;Haorui Huang ,&nbsp;Fanwen Zhao ,&nbsp;Xia Fan ,&nbsp;Li Bai ,&nbsp;Xinhao Zhang ,&nbsp;Keping Ye","doi":"10.1016/j.ijfoodmicro.2025.111067","DOIUrl":"10.1016/j.ijfoodmicro.2025.111067","url":null,"abstract":"<div><div>This study investigated the difference in survival among <em>Listeria monocytogenes</em> (<em>LM</em>) 10403S (highly pathogenic strain) and M7 (low pathogenic strain) in sausage under a simulated digestive environment, and established intestinal organoids and macrophages co-culture model to further explore the virulence expression difference to intestinal cells between <em>LM</em> 10403S and M7 after <em>in vitro</em> gastrointestinal digestion. Results showed that, compared with <em>LM</em> M7, <em>LM</em> 10403S exhibited a high survival rate during <em>in vitro</em> digestion, which may be due to the increased expression of stress response-related genes. In addition, the expression of virulence genes in <em>LM</em> 10403S was significantly higher than in <em>LM</em> M7 under the gastrointestinal environment. Furthermore, in the intestinal organoids and macrophages co-culture model infected by <em>LM</em> 10403S and M7 after <em>in vitro</em> gastrointestinal digestion, results showed that, compared with the <em>LM</em> M7 group, the <em>LM</em> 10403S group had significantly lower budding rate and significantly higher mortality of organoids. Also, the significantly increased LDH release and inflammatory factors (TNF-α and IL-1β) in the <em>LM</em> 10403S group were observed, and the main virulence genes (<em>iap</em>, <em>inlA</em>, <em>inlB</em>, <em>actA</em>, <em>hly</em>, <em>plcA,</em> and <em>plcB</em>) of 10403S were significantly highly expressed than <em>LM</em> M7 during the cell infection. These results reflected that the reason for the different pathogenicity between <em>LM</em> 10403S and M7 may be due to the high tolerance and the expression of virulence genes than <em>LM</em> M7 during gastrointestinal digestion and cell infection, which would be expected to provide a better understanding of the infection mechanisms among different pathogenic strains of L. <em>monocytogenes</em> in food.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111067"},"PeriodicalIF":5.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004744","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":"Spent coffee ground disrupts Listeria monocytogenes biofilm formation through inhibition of motility and adhesion via quorum sensing regulation","authors":"Jinho Lee ,&nbsp;Jihyun Park ,&nbsp;Jihyeon Baek,&nbsp;Suyeon Lee,&nbsp;Eunsu Seo,&nbsp;Seunghyeon Kim,&nbsp;Hyewon Choi,&nbsp;Seok-Seong Kang","doi":"10.1016/j.ijfoodmicro.2025.111066","DOIUrl":"10.1016/j.ijfoodmicro.2025.111066","url":null,"abstract":"<div><div>Spent coffee grounds (SCGs) have been explored for use as various bioresources, such as biofuels, and are known to possess biological functions, including antioxidant activity. However, the antibiofilm properties of SCGs against pathogenic bacteria have not been fully investigated. Therefore, this study aimed to highlight the inhibitory effects of SCG extract (SCGE) on biofilm formation in <em>Listeria monocytogenes</em> and investigated the underlying mechanisms. Treatment with SCGE disrupted both biofilm formation and architecture in <em>L</em>. <em>monocytogenes</em>. Furthermore, SCGE reduced autoaggregation and surface hydrophobicity. However, SCGE did not affect the viability of planktonic <em>L</em>. <em>monocytogenes</em>, suggesting that the decrease in biofilm formation was not attributed to decreased viability. Instead, SCGE downregulated motility- and adhesion-related genes in <em>L</em>. <em>monocytogenes</em>. Furthermore, SCGE impaired the swimming motility of <em>L</em>. <em>monocytogenes</em>. It also impaired adhesion to and invasion of intestinal epithelial cells. Moreover, SCGE suppressed the production of autoinducer-2, indicating the inhibition of quorum sensing signaling. Taken together, these findings suggest that SCGE inhibits biofilm formation in <em>L</em>. <em>monocytogenes</em> by modulating quorum sensing signaling, which regulates bacterial motility and adhesion.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111066"},"PeriodicalIF":5.0,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004733","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":"Application of spray-dried bacteriocins as cheese biopreservatives","authors":"Romina M. Lenz ,&nbsp;M. Virginia Guitián ,&nbsp;Fernando J. Villalva ,&nbsp;Enzo Goncalvez de Oliveira ,&nbsp;M. Cecilia Soria ,&nbsp;M. Carina Audisio ,&nbsp;Carolina Ibarguren","doi":"10.1016/j.ijfoodmicro.2025.111062","DOIUrl":"10.1016/j.ijfoodmicro.2025.111062","url":null,"abstract":"<div><div><em>Listeria monocytogenes</em> can contaminate refrigerated ready-to-eat foods, such as cheeses. Enterocins, with a strong listericidal effect, constitute a natural alternative to control this pathogen in food. To optimize their antimicrobial action in food matrices, bacteriocins can be immobilised in edible coatings through spray drying technology which allows the large-scale production of microcapsules of bioactive molecules. The aim of this work was to evaluate the antimicrobial effectiveness of <em>Enterococcus avium</em> DSMZ17511 bacteriocins, obtained in a low-cost culture broth (HS-L), spray-dried assaying different thermoprotective materials (maltodextrin, cheese whey and brea gum), and incorporated into agar-based active coatings applied on goat cheese pieces artificially contaminated with L. <em>monocytogenes</em> 99/287. The bacteriocin solution (BS) powders, labelled HS-L BS, maintained the antimicrobial activity even after 90 days of storage, with titres up to 128,000 UA/g, with the least thermoprotective effect exerted by brea gum (64,000–32,000 UA/g). An increase in antimicrobial titre was observed for all bacteriocin powders after 3 months, despite storage conditions; probably due to a release effect from the encapsulated bacteriocin or a combined release and gradual dehydration effect of the encapsulating matrix. Also, the dried products stored at 25 °C hydrated easily, while refrigeration or freezing did not affect the powders texture. For coatings applied on fresh goat cheese, only a difference of 0.5 log cfu/mL was observed between the viability of L. <em>monocytogenes</em> in the contaminated active-coated cheese and the control without coating. Instead, for the commercial goat cheese, with a drier matrix, the viability values stood 1.0 log cfu/mL below the control uncoated cheeses for up to 10 days. These spray dried bacteriocin powders provide an alternative for their application as food biopreservatives, since stable dehydrated products were obtained, with prolonged antimicrobial activity, and with verified inhibitory action in a food matrix.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"430 ","pages":"Article 111062"},"PeriodicalIF":5.0,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142983542","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}