Foodborne pathogens and disease最新文献

{"title":"Production of Reactive Oxygen Species Induced by Peracetic Acid Enhances Bactericidal Activity and Mutagenesis in <i>Salmonella</i> Typhimurium.","authors":"Mohammed K W Al-Doury, Elena G Olson, Steven C Ricke, Michael J Rothrock, Young Min Kwon","doi":"10.1177/15353141251384160","DOIUrl":"10.1177/15353141251384160","url":null,"abstract":"<p><p>Peracetic acid (PAA) is extensively used in poultry processing, but its bactericidal mechanism remains poorly understood. Reactive oxygen species (ROS) are linked to bacterial cell death by many bactericidal agents. This study investigated the role of ROS in PAA against <i>Salmonella</i> Typhimurium 14028 using bacterial suspensions treated with PAA alone (20 ppm), PAA combined with 2,2'-dipyridyl (Dip; iron chelator) or with thiourea (ROS scavenger) followed by incubation at 37°C for 1 h. Post-incubation, serial dilutions were plated on Luria-Bertani agar to determine colony-forming units per milliliter. Additionally, eight single-deletion mutants and the wild-type (control) of <i>Salmonella</i> Typhimurium 14028 were tested for survivability after exposure to PAA (treatment; 20 ppm) and hydrogen peroxide (H₂O₂; control). The mutants were categorized by predicted ROS impact: increase in ROS production (<i>atpC</i>, <i>gnd</i>, <i>nuoG</i>, <i>pta, sdhC</i>, and <i>zwf</i>) and no change in ROS production (negative control; <i>edd</i> and <i>pykA</i>). Finally, rifampicin-based selection assay was utilized to evaluate the mutation rate of the wild-type strain in the presence of PAA (60 ppm), H₂O₂ (control), and PAA + thiourea. Treatment with 20 ppm PAA significantly (<i>p</i> < 0.05) reduced the viability of <i>Salmonella</i> Typhimurium 14028 by a log₁₀ reduction of 0.34, while co-treatment with thiourea restored counts to control level. The survival of the mutants predicted to increase ROS production was significantly reduced compared with the control mutants and wild-type strain (<i>p</i> < 0.05). Exposure to sublethal PAA led to a 28-fold increase in mutation rate suggesting the production of ROS by PAA was responsible for the observed increase. ROS production is a significant component of PAA's bactericidal activity against <i>Salmonella</i> Typhimurium, and increasing ROS production might be exploited to enhance PAA-mediated killing of <i>Salmonella</i> Typhimurium. ROS production by PAA can lead to the development of antibiotic resistance in <i>Salmonella</i> Typhimurium when cells manage to escape cell death.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"755-762"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145185228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 a Novel <i>Pseudomonas psychrophila</i> Phage P-2FD and Its Endolysin.","authors":"Xinran Yu, Congcong Shi, Bingbing Heng, Hongxun Wang, Huajuan Wang, Min Zhou","doi":"10.1177/15353141251382152","DOIUrl":"10.1177/15353141251382152","url":null,"abstract":"<p><p><i>Pseudomonas</i> is a common food spoilage bacterium that can cause spoilage of milk, eggs, fish, and other food products under low temperature conditions. In this study, a total of four <i>Pseudomonas</i> phages were isolated from spoiled fish and shrimp, and the biological characterization of one of them, <i>Pseudomonas psychrophila</i> phage P-2FD, which exhibited a wider host spectrum, was carried out. Morphological analyses showed that phage P-2FD belonged to the <i>Podoviridae</i> family and the <i>Caudovirales</i> order. When the multiplicity of infection (MOI) was 1000, the growth of <i>P. psychrophila</i> was almost completely inhibited before 9 h. When phage P-2FD treated <i>P. psychrophila</i> in grass carp with an MOI of 1000, the bacterial counts were reduced by 1.77 log₁₀ CFU/g compared with the control group at 4°C for 96 h, indicating that phage P-2FD effectively inhibited the growth of <i>P. psychrophila</i>. Genomic analysis showed that P-2FD was a novel phage, and the whole genome length of P-2FD was 40,453 bp with 42 open reading frames (ORFs). The phage endolysin LysP-2FD was expressed in <i>Escherichia coli</i> BL21 (DE3) and purified, and the lytic rate against <i>P. psychrophila</i> was 78.17% at a concentration of 20 μmol/L. The present study suggests that phage P-2FD and endolysin can be used as potential antimicrobial agents for the control of <i>P. psychrophila</i> in the food industry.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"789-798"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145174413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbiological Examination of Frozen Corn Linked to a National Salmonellosis Outbreak Reveals Gaps in Product Hygiene and Thermal Inactivation.","authors":"Mary Rao, Sandeep Tamber","doi":"10.1177/15353141251386427","DOIUrl":"10.1177/15353141251386427","url":null,"abstract":"<p><p>A nationwide outbreak of <i>Salmonella enterica</i> ser. Enteritidis linked for the first time to frozen corn occurred in Canada from September 2021 to January 2022. To identify potential contributing factors, contaminated corn samples were analyzed and compared to unrelated retail samples. Contaminated corn samples had significantly lower sugar content (9% vs. 12%) and higher levels of background microbiota (total aerobic mesophiles, <i>Enterobacteriaceae</i>, and total coliforms) compared to retail samples. <i>S</i>. <i>enterica</i> ser. Enteritidis was recovered from the contaminated corn samples at low levels (average = 5 most probable number [MPN]/100 g). These levels were stable over 3 years of frozen storage (average = 3 MPN/100 g). The response of the outbreak strain to heat was comparable to laboratory strains of the same serovar. Heating retail corn samples artificially inoculated with 1 × 10⁸ colony-forming units of <i>S</i>. <i>enterica</i> ser. Enteritidis by immersion in a 90°C water bath for 7 min resulted in a linear decrease of cells over time as the temperature of the food sample increased. Extrapolation of the data suggests a five-log reduction would require a cooking time of 8 min, corresponding to a food sample temperature of 66°C. However, cooking naturally contaminated corn samples beyond these parameters to a temperature of 74°C failed to completely eliminate <i>Salmonella</i>. The results of this study highlight the hazards associated with the presence of <i>Salmonella</i> in frozen vegetables and emphasize the need for improved hygiene during processing and the development of clear, validated cooking procedures to mitigate risks associated with frozen vegetables.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"763-768"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145231877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic and Genotypic Characterization of <i>Escherichia coli</i> O157:H7 Harboring <i>stx2</i> and <i>stx1</i>&<i>stx2</i> Genes Isolated from Frozen Raw Beef Meat and Beef Liver Samples.","authors":"Hany M Yehia, Nourhan H Mohamed, Hanaa Sonbol, Abeer S Aloufi, Shereen M Korany, Manal F El-Khadragy, Ahmed S Sami, Rajapandiyan Krishnamoorthy, Abdulhakeem Alzahrani, Mohammad A Alshuniaber","doi":"10.1177/15353141251403446","DOIUrl":"https://doi.org/10.1177/15353141251403446","url":null,"abstract":"<p><p>Shiga toxin (<i>Stx</i>) is the main virulence factor of enterohemorrhagic <i>Escherichia coli</i>. Between its two types<i>-Stx1</i> and <i>Stx2</i>-<i>E. coli</i> O157:H7 produces <i>Stx2</i>, which causes more severe infections compared with <i>Stx1</i> or both <i>Stx1</i> and <i>Stx2</i>. In this study, we isolated and identified <i>E. coli</i> O157:H7 from frozen raw beef samples and both <i>Stx1</i> and <i>Stx2</i> from frozen raw beef liver samples collected from the Al-Riyadh market in Saudi Arabia. Phenotypic detection was conducted using suitable and specific media-sorbitol MacConkey agar and <i>Salmonella</i> chromogenic agar-with <i>E. coli</i> O157:H7 appearing as colorless and blue-colored colonies, respectively. Furthermore, serological testing using DrySpot <i>E. coli</i> O157 latex agglutination tests was conducted to verify the identification and detection results. A conventional polymerase chain reaction was conducted using specific primers of the genes encoding <i>Stx1</i> and <i>Stx2</i> for further verification. The results showed that among the 50 frozen raw beef meat samples, 11 colonies harbored the <i>stx2</i> gene with an amplicon of 420 bp (22%). Meanwhile, among the 50 frozen raw beef liver samples, 5 samples harbored either both the <i>stx1</i> and <i>stx2</i> genes or the <i>stx2</i> gene alone, with amplicons of 310 and 420 bp, respectively (10%), while 6 samples harbored only the <i>stx2</i> gene (12%). Overall, <i>E. coli</i> O157:H7 containing <i>Stx2</i> was prevalent in beef meat, while <i>Stx1</i> and/or <i>Stx2</i> were identified in beef liver. Furthermore, <i>E. coli</i> O157:H7 harboring <i>stx2</i> genes were found to be more resistant to different antibiotic classes (50%) than strains containing <i>stx1</i> and/or <i>stx</i>2 genes (42.28%). Moreover, doubling time in tryptic soy medium extended to 60 min for strains harboring <i>stx2</i> alone and 55 min for strains harboring s<i>tx1</i> and/or <i>stx2</i>. In conclusion, <i>E. coli</i> O157:H7 was found to be considerably more multidrug resistant than <i>Stx1</i> and/or <i>Stx2</i> with respect to several conditions and circumstances.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":"23 11","pages":"769-780"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149069510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unpacking Environment Overrides Meat Type in Shaping the Bacterial Community and Potential Spoilage Organisms of Ready-to-Eat Meats During Refrigerated Storage.","authors":"Shuran Yang, Xiaozhe Qi, Zixin Peng, Li Bai, Dajin Yang","doi":"10.1177/15353141261466183","DOIUrl":"10.1177/15353141261466183","url":null,"abstract":"<p><p>Microbial contamination in ready-to-eat (RTE) meat products poses a significant food safety risk, as evidenced by previous reports of high aerobic plate counts and pathogen prevalence. Understanding the post-unpacking dynamics of bacterial communities is crucial for guiding consumer practices. In this study, 90 RTE meat samples of which the varieties include beef products, chicken products, duck products, pig products, mutton products, and donkey products, were collected to analyze microbial community structure by 16S rRNA amplicon sequencing. These samples were collected on the 7th, 14th and 21st day respectively after unpacking. In all these samples, Proteobacteria and Firmicutes made up more than 98% of total bacteria. <i>Pseudomonas</i>, <i>Staphylococcus</i>, <i>Psychrobacter</i>, <i>Carnobacterium</i>, and <i>Shewanella</i> were the most abundant genera on average in the 90 samples. Microbial communities of samples on day 21 were significantly different (<i>p</i> < 0.05) from those on day 7 and day 14. The patterns of microbial community change over time were similar between the two sampling sites, Shandong and Henan. On day 14 and day 21, the microbial group clusters were significantly different from each other when grouped by unpacking site factor (Permanova index < 0.05). The abundance of potential spoilage and pathogenic bacteria, such as <i>Pseudomonas, Staphylococcus,</i> and <i>Enterobacteriaceae</i>, increased after 14 days of storage. Variety-specific operational taxonomic units showed very low abundance in the microbial community. In conclusion, this study demonstrates that the unpacking environment, rather than the meat species, becomes the dominant factor influencing bacterial community succession after 14 days of storage. This finding highlights the critical importance of minimizing post-unpacking contamination and suggests that the storage time after opening should be strictly controlled, particularly beyond 2 weeks, to mitigate the growth of potential spoilage and pathogenic bacteria.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"781-788"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148390253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ocular Toxoplasmosis Infection Leading to Uveitis or Chorioretinal Lesions: A Systematic Review.","authors":"Kylie Boyd, Kristina Condrey, Ayeisha Rosa Hernandez, Erika Austhof, Lifeng Lin, Joanne Dehnbostel, Sandra Hoffmann, Christina Flaxel, Zelin Wang, Kristen Pogreba-Brown","doi":"10.1177/15353141251382884","DOIUrl":"10.1177/15353141251382884","url":null,"abstract":"<p><strong>Introduction: </strong><i>Toxoplasma gondii</i> (<i>T. gondii</i>) infections affect approximately 30% of the population worldwide. This systematic review of ocular sequelae from toxoplasmosis explores in greater depth the outcomes found in our previous scoping review. Uveitis and ocular lesions can be acute or recurrent following infection and result in long-term and often irreversible effects.</p><p><strong>Methods: </strong>We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and used the Cochrane risk-of-bias tool to evaluate articles for inclusion. Data extraction included the frequency and proportion of participants who developed uveitis or chorioretinal lesions, the type, anatomical locations affected, and disease burden.</p><p><strong>Results: </strong>Utilizing an inclusion criterion that included a physical examination combined with laboratory confirmation, 63 articles from 27 countries spanning a publication period from 2000 to 2023 were included. Most reported outcomes in these articles included uveitis (<i>n</i> = 61), chorioretinal lesions (<i>n</i> = 42), or both (<i>n</i> = 40). Meta analysis results indicate that the proportion of ocular toxoplasmosis (OT) cases resulting in lesions was lower than uveitis, with the highest estimates reported in Asia.</p><p><strong>Discussion: </strong>Uniform diagnostic methodology was only found in articles describing congenital case populations arising from toxoplasmosis monitoring programs. Consistent use of nomenclature, consistent diagnostic testing, and standardized reporting of patient demographics by researchers would greatly aid in understanding the burden of disease experienced.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"723-735"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145257742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Quorum Quenching Activity of Lactic Acid Bacteria Isolated from Fermented Foods via <i>Chromobacterium violaceum</i> Biosensor.","authors":"Nitchakan Darai, Wattana Pelyuntha","doi":"10.1177/15353141251384814","DOIUrl":"10.1177/15353141251384814","url":null,"abstract":"<p><p>Quorum sensing (QS) is a bacterial communication system regulating virulence, biofilm formation, and antimicrobial resistance via autoinducer signaling molecules. Disrupting QS, known as quorum quenching (QQ), represents a promising strategy for controlling bacterial pathogenicity without promoting antibiotic resistance. This study aimed to screen lactic acid bacteria (LAB) isolated from diverse fermented foods for QS inhibition (QSI) activity using <i>Chromobacterium violaceum</i> ATCC 12472 as a biosensor. Among 208 LAB isolates, only 11 strains inhibited violacein production, indicative of significant QSI activity. Further assessment with cell-free culture supernatants revealed that isolate WPL10 demonstrated the highest violacein inhibition at 18.4%. In contrast, 28 isolates exhibited weak activity, and the remaining 169 showed no inhibitory effect. The most active isolate, identified as <i>Lactiplantibacillus plantarum</i> WPL10 via Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometer (MALDI-TOF MS), showed promising QQ potential likely mediated by metabolic products or enzymatic mechanisms. This research highlights fermented foods as valuable sources of natural QQ agents and identifies <i>L. plantarum</i> WPL10 as a potential biocontrol agent for improving food safety by reducing bacterial virulence and biofilm formation.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"799-802"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145199042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preharvest Animal Management Controls and Intervention Options for Reducing <i>Escherichia coli</i> O157:H7 and Other Shiga Toxin-Producing <i>E. coli</i> Shedding in Cattle: A Critical Analysis.","authors":"Hunter G Perez, Darren S Seidel, Todd R Callaway","doi":"10.1177/15353141251386418","DOIUrl":"10.1177/15353141251386418","url":null,"abstract":"<p><p>Shiga toxin-producing <i>Escherichia coli</i> (STEC; also known as enterohemorrhagic <i>E. coli</i>) are virulent foodborne pathogenic bacteria that are frequently isolated from the gastrointestinal tract of beef and dairy cattle. The beef industry is committed to ensuring a safe and wholesome food supply; as a result, the industry has investigated a number of methods to reduce STEC by implementing changes on the farm and in the processing plant. While interventions can reduce STEC entry into the food chain, the introduction of hurdles does not remove the need to ensure animal health and utilize proper animal management and sanitation procedures on the farm and in the processing plant. This review addresses the latest literature investigating potential preharvest STEC (both <i>E. coli</i> O157:H7 and other non-O157:H7 STEC serotypes) intervention strategies. On-farm interventions to reduce STEC in cattle can be divided up into three broad categories: (1) animal management and transport practices, (2) feed and water management, and (3) live animal treatments. Ultimately, preharvest intervention strategies are imperfect and may not always be complementary with other pathogen reduction strategies as part of a coordinated multiple-hurdle approach. By reducing the burden of STEC entering processing plants, we can increase the effectiveness of in-plant interventions and further reduce human illnesses.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"736-754"},"PeriodicalIF":2.3,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145257767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Whole-Genome Sequencing-Based Characterization and Antimicrobial Resistance Analysis of Shiga Toxin-Producing <i>Escherichia coli</i> Isolated from Retail Meat Products.","authors":"Qian Zhang, Shengnan Liang, Fangyuan Cui, Zongbo Lu, Lihong Cheng, Jinli Jia, Lu Qian, Ningning Jiang, Xiangyuan Zhang, Hui Yuan","doi":"10.1177/15353141261497565","DOIUrl":"https://doi.org/10.1177/15353141261497565","url":null,"abstract":"<p><p>Shiga toxin-producing <i>Escherichia coli</i> (STEC), a zoonotic foodborne pathogen, has become a critical global public health issue. This study investigates molecular traits and antimicrobial resistance (AMR) mechanisms of STEC strains derived from retail meat products sourced from domestic production in Liaocheng city, Shandong province, China, to inform health risk assessment. Using quantitative real-time polymerase chain reaction (qPCR), phenotypic AMR testing, and whole-genome sequencing (WGS), 38 STEC isolates were identified from 400 retail meat products, with an isolation rate of 9.5%. Significant differences in STEC isolation rates were detected among different meat types, and mutton exhibited a relatively high isolation rate of 26.09%. Genomic virulence analysis showed that there were higher proportions of single <i>stx₂</i> (58.33%) and dual <i>stx₁/stx₂</i> genotypes (33.33%) in mutton isolates than in beef (<i>stx₂</i>: 48.00%, dual <i>stx₁/stx₂</i>: 12.00%), and only the <i>stx₂</i> gene was found in pork isolates. STEC isolates exhibited marked serotypic diversity, including O128ac:H2, O168:H7, O178:H7, O2:H25, and O6:H10. Multilocus sequence typing analysis revealed heterogeneous sequence type (ST) distributions among isolates, with <i>ST10</i>, <i>ST25</i>, and <i>ST2722</i> as dominant STs, suggesting diverse contamination sources. STEC isolates exhibited high phenotypic resistance to tetracycline (TET) (68.42%), which corresponded to the highest detection rate of the TET resistance gene <i>tet(A)</i> at the genomic level. All isolates were susceptible to ertapenem, meropenem, ceftazidime, ceftazidime-avibactam, ciprofloxacin, and amikacin. Multidrug resistance (MDR) analysis indicated that 16 STEC isolates were MDR strains, with beef-derived isolates having relatively high MDR rates. This study verifies the occurrence of STEC in retail meat, highlighting prevalent AMR and substantial genetic heterogeneity among isolates. The findings underscore the necessity of systematic surveillance to limit STEC transmission along the meat supply chain and facilitate targeted food safety interventions.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"15353141261497565"},"PeriodicalIF":2.3,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149180438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gram-Positive Bacteria Responses to Antibiotics When Incubated in Fecal <i>in Vitro</i> Microcosms from Swine Supplemented with Chlorophyllin.","authors":"Robin C Anderson, Elena G Olson, Regina C S Mendonça, Mark A Rasmussen, Kristina M Feye, Steven C Ricke","doi":"10.1177/15353141261497339","DOIUrl":"https://doi.org/10.1177/15353141261497339","url":null,"abstract":"<p><p>Standardized antimicrobial susceptibility assays use defined culture media and may therefore not fully account for gastrointestinal constituents that influence bacterial responses to antibiotics. This study evaluated whether swine fecal extracts, including extracts associated with dietary chlorophyllin supplementation, altered the antimicrobial susceptibility of multidrug-resistant Gram-positive bacteria. Fecal material collected from pigs fed either a non-chlorophyllin or chlorophyllin-supplemented diet was pooled by dietary group, processed to produce clarified fecal extracts, and incorporated at 20% (vol/vol) into Mueller-Hinton (MH) broth. Minimum inhibitory concentrations (MICs) of chlortetracycline, penicillin, carbadox, tylosin, ceftazidime, and norfloxacin were determined for selected <i>Staphylococcus</i>, <i>Streptococcus</i>, and <i>Enterococcus</i> strains using broth microdilution and compared with MICs obtained in standard MH broth. Fecal extracts altered MICs in a strain- and antibiotic-dependent manner. Extracts from chlorophyllin-fed pigs produced particularly pronounced reductions in susceptibility thresholds for several combinations, including >128- to >256-fold decreases in chlortetracycline MICs for <i>Streptococcus agalactiae</i>, <i>Staphylococcus hyicus</i>, and <i>Enterococcus faecium</i> H 1019 V; >253-fold decreases in penicillin MICs for several strains; and >32- to >256-fold decreases in ceftazidime MICs for four strains. Carbadox MICs were also reduced in several organisms. However, these effects were not universal: tylosin MICs were generally unchanged or increased, and norfloxacin MICs were unchanged or increased in all strains tested. Fecal extracts from non-chlorophyllin-fed pigs also altered MICs, demonstrating that the fecal matrix itself influenced phenotypic antimicrobial susceptibility. These findings indicate that antimicrobial susceptibility measured under standard laboratory conditions may differ substantially in the presence of fecal-derived constituents and support further characterization of the metabolites responsible for these effects.</p>","PeriodicalId":12333,"journal":{"name":"Foodborne pathogens and disease","volume":" ","pages":"15353141261497339"},"PeriodicalIF":2.3,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149148306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}