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Flow cytometry (FCM) provides unique information on bacterial viability and physiology, allowing a real-time early warning antimicrobial and antibiofilm monitoring system for preventing the spread risk of foodborne disease. The present work used a combined culture-based and FCM approach to assess the in vitro efficacy of essential oils (EOs) from condiment plants commonly used in Mediterranean Europe (i.e., thyme EO, oregano EO, basil EO, and lemon EO) against planktonic and sessile cells of food-pathogenic Listeria monocytogenes 56 LY, and contaminant and alterative species Escherichia coli ATCC 25922 and Pseudomonas fluorescens ATCC 13525. Evaluation of the bacterial response to the increasing concentrations of natural compounds posed FCM as a crucial technique for the quantification of the live/dead, and viable but non-culturable (VBNC) cells when antimicrobial agents exert no real bactericidal action. Furthermore, the FCM results displayed higher numbers of viable bacteria expressed as Active Fluorescent Units (AFUs) with a greater level of repeatability compared with outcomes of the plate-count method. Overall, accurate counting of viable microbial cells is a critically important parameter in food microbiology, and flow cytometry provides an innovative approach with high-throughput potential for applications in the food industry as "flow microbiology"., Competing Interests: Declaration of competing interest Annamaria Bevivino reports financial support was provided by European Commission—NextGenerationEU programme Project SUS-MIRRI.IT “Strengthening the MIRRI Italian Research Infrastructure for Sustainable Bioscience and Bioeconomy,” Project code IR0000005, CUP D13C22001390001. Luciana Di Gregorio reports financial support was provided by the European Commission—NextGenerationEU programme Project ON Foods—Research and innovation network on food and nutrition Sustainability, Safety and Security—Working ON Foods, Project code PE00000003, CUP I83C22001790001; and European Commission—NextGenerationEU programme Project SUS-MIRRI.IT “Strengthening the MIRRI Italian Research Infrastructure for Sustainable Bioscience and Bioeconomy,” Project code IR0000005, CUP D13C22001390001. Manuela Costanzo reports financial support was provided by the European Commission—NextGenerationEU programme Project SUS-MIRRI.IT “Strengthening the MIRRI Italian Research Infrastructure for Sustainable Bioscience and Bioeconomy,” Project code IR0000005, CUP D13C22001390001. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Carvacrol has been recognized as an efficient growth inhibitor of food pathogens. However, carvacrol oil is poorly water-soluble and can be oxidized, decomposed or evaporated when exposed to the air, light, or heat. To overcome these limitations, a carvacrol nanoemulsion was developed and its antimicrobial activity against food pathogens evaluated in this study. The nanoemulsion containing 3% carvacrol oil, 9% surfactants (HLB 11) and 88% water, presented good stability over a period of 90 days. In general, the carvacrol nanoemulsion (MIC: 256 µg ml -1 for E. coli and Salmonella spp., 128 µg ml -1 for Staphylococcus aureus and Pseudomonas aeruginosa) exhibited improved antimicrobial activity compared to the free oil. The carvacrol nanoemulsion additionally displayed bactericidal activity against Escherichia coli, P. aeruginosa and Salmonella spp. Therefore, the results of this study indicated that carvacrol oil nanoemulsions can potentially be incorporated into food formulations, wherein their efficacy for the prevention and control of microbial growth could be evaluated., (© 2020 The Society for Applied Microbiology.)

Food-borne pathogens and antimicrobial resistance (AMR) represent the significant public health challenges in the 21st century. Increased emergence of AMR in major zoonotic food-borne pathogens (Salmonella, Campylobacter) and in commensal bacteria (E. coli, enterococci), its presence in agro-food (meat) chain and environment, including control/prevention of AMR transfer from food-producing animals to humans via food consumption, is of utmost importance for public health. This review highlights the most relevant risk mitigation strategies for AMR in the meat production chain within One Health context. The monitoring and surveillance systems for AMR in meat chain are presented and briefly discussed, including sampling schemes, susceptibility testing, clinical resistance and epidemiological cut-off values. The most effective approaches to track and manage AMR in farm-abattoir-meat processing-retail continuum have been recommended, including aspects of international harmonization of critically important antimicrobials for human and veterinary use. The successful AMR monitoring and control in the meat chain can be achieved by evidence-based and integrated approach within One Health context. The application of state-of-the-art technologies and methods for detection and tracking of zoonotic food borne pathogens and AMR, such as Whole Genome Sequencing supported with data processing using Artificial Intelligence (machine learning), can contribute to achieving this goal. [ABSTRACT FROM AUTHOR]

The antibacterial and antibiofilm effects of rosehip vinegar and propolis extract, separately and as a mixture, were investigated on Staphylococcus aureus and Escherichia coli O157:H7. The organoleptic properties and tissue integrity of sardine fish treated with this mixture were evaluated. The propolis extract was found to have a higher inhibitory effect (>80%) on S. aureus (up to the 5th dilution) than on E. coli O157:H7 (only at the first dilution). A potential synergistic antibacterial and antibiofilm effect of the mixture was observed with an inhibition ratio of ≥50%. This mixture may extend the shelf life of sardines as a natural antibacterial/antibiofilm preservative. [ABSTRACT FROM AUTHOR]

The consumption of organic food has increased in recent years. In organic rearing animals are exposed to outdoor conditions, which may increase their risk of infection from various pathogens. In the present study the occurrence of the most significant foodborne pathogenic bacteria in organic meat and ready-to-eat organic meat products was assessed. Out of 100 raw organic meat samples tested, 72 were contaminated with bacterial pathogens. The highest percentage of contaminated samples was observed in poultry meat (92.5%) followed by pork meat (66.7%). Furthermore, 50.0% of beef origin samples were positive for the bacteria tested. L. monocytogenes was found in 39.0% of samples, S. aureus was identified in 37.0%, Campylobacter in 20.0%, Salmonella in 8.0% and Shigatoxin-producing E. coli in 4.0% of raw meat samples. In 31.0% of samples a co-occurrence of two (83.9%) or three (16.1%) pathogens was observed. Among 100 samples of organic meat products tested, only L. monocytogenes was found in 5.0% of samples. The result of the present study indicated that organic food may be a source of harmful microorganisms that may pose foodborne infections to consumers. [ABSTRACT FROM AUTHOR]

Dish sponges are known to support the proliferation of human bacterial pathogens, yet they are commonly used by consumers. Exposure to foodborne pathogens via sponge use may lead to illness, a serious concern among susceptible populations. The extent of exposure risks from sponge use has been limited by constraints associated with culture‐independent or dependent methods for bacterial community characterization. Therefore, five used dish sponges were characterized to evaluate the presence of viable bacterial foodborne pathogens using the novel application of propidium monoazide (PMA) treatment and targeted 16S rRNA gene amplicon sequencing. Select pathogen viability was confirmed using targeted selective enrichment. The taxonomic abundance profiles of total and viable sponge microbiomes did not vary significantly. The numbers of unique bacterial species (p = 0.0465) and foodborne pathogens (p = 0.0102) identified were significantly lower in viable sponge microbiomes. Twenty unique bacterial foodborne pathogens were detected across total and viable sponge microbiomes, and three to six viable foodborne pathogens were identified in each sponge. Escherichia coli and Staphylococcus aureus were identified in each viable sponge microbiome, and viable E. coli were recovered from two sponges via targeted selective enrichment. These findings suggest that sponge‐associated bacterial communities are primarily viable and contain multiple viable bacterial foodborne pathogens. [ABSTRACT FROM AUTHOR]

Background: The urgent need for affordable and rapid detection methodologies for foodborne pathogens, particularly Escherichia coli (E. coli), highlights the importance of developing efficient and widely accessible diagnostic systems. Dark field microscopy, although effective, requires specific isolation of the target bacteria which can be hindered by the high cost of producing specialized antibodies. Alternatively, M13 bacteriophage, which naturally targets E. coli, offers a cost-efficient option with well-established techniques for its display and modification. Nevertheless, its filamentous structure with a large length-diameter ratio contributes to nonspecific binding and low separation efficiency, posing significant challenges. Consequently, refining M13 phage methodologies and their integration with advanced microscopy techniques stands as a critical pathway to improve detection specificity and efficiency in food safety diagnostics. Methods: We employed a dual-plasmid strategy to generate a truncated M13 phage (tM13). This engineered tM13 incorporates two key genetic modifications: a partial mutation at the N-terminus of pIII and biotinylation at the hydrophobic end of pVIII. These alterations enable efficient attachment of tM13 to diverse E. coli strains, facilitating rapid magnetic separation. For detection, we additionally implemented a convolutional neural network (CNN)-based algorithm for precise identification and quantification of bacterial cells using dark field microscopy. Results: The results obtained from spike-in and clinical sample analyses demonstrated the accuracy, high sensitivity (with a detection limit of 10 CFU/μL), and time-saving nature (30 min) of our tM13-based immunomagnetic enrichment approach combined with AI-enabled analytics, thereby supporting its potential to facilitate the identification of diverse E. coli strains in complex samples. Conclusion: The study established a rapid and accurate detection strategy for E. coli utilizing truncated M13 phages as capture probes, along with a dark field microscopy detection platform that integrates an image processing model and convolutional neural network. [ABSTRACT FROM AUTHOR]

Foodborne pathogens may cause foodborne illness, which is among the major health problems worldwide. Since the therapeutic options for the treatment of the disease are becoming limited as a result of antibacterial resistance, there is an increasing interest to search for new alternatives of antibacterial. Bioactive essential oils from Curcuma sp become potential sources of novel antibacterial substances. The antibacterial activity of Curcuma heyneana essential oil (CHEO) was evaluated against Escherichia coli, Salmonella typhi, Shigella sonnei, and Bacillus cereus. The principal constituents of CHEO are ar-turmerone, β-turmerone, α-zingiberene, α-terpinolene, 1,8-cineole, and camphor. CHEO exhibited the strongest antibacterial activity against E. coli with a MIC of 3.9 µg/mL, which is comparable to that of tetracycline. The combination of CHEO (0.97 µg/mL) and tetracycline (0.48 µg/mL) produced a synergistic effect with a FICI of 0.37. Time-kill assay confirmed that CHEO enhanced the activity of tetracycline. The mixture disrupted membrane permeability of E. coli and induced cell death. CHEO at MIC of 3.9 and 6.8 µg/mL significantly reduced the formation of biofilm in E. coli. The findings suggest that CHEO has the potential to be an alternative source of antibacterial agents against foodborne pathogens, particularly E. coli. [ABSTRACT FROM AUTHOR]

Background: Extended-spectrum-β-lactamase (ESBL) and carbapenemase-producing Enterobacterales and Acinetobacter spp. pose significant challenges as nosocomial pathogens, demonstrating resistance against various antimicrobials. Their presence in food suggests that hospital kitchens could serve as antibiotic resistance reservoirs leading to patients' infection. Objectives: The aim of this study was to assess the prevalence and characteristics of β-lactam-resistant strains of Escherichia coli, Klebsiella pneumoniae, and Acinetobacter spp. isolated from the kitchen environment and from the staff of two Greek hospitals. Methods: Strains were recovered after selective isolation with β-lactams and were identified with MALDI–TOF MS. Antimicrobial susceptibility and presence of common β-lactamase genes were evaluated. Protein profiles were examined to analyze potential relationships of the strain with those from hospital patients. E. coli strains were further categorized into phylogenetic groups. Results: The overall prevalence in the kitchen environment was 4.5%, 1.5%, and 15.0% for E. coli, K. pneumoniae, and Acinetobacter spp., respectively, whereas the prevalence of Acinetobacter spp. in human skin was 4.0%. Almost all strains were multidrug-resistant. All E. coli strains were ESBL producers and belonged to phylogroups A and B1. All K. pneumoniae and seven Acinetobacter strains were carbapenemase-producers. A protein profile analysis showed relatedness between chicken and kitchen environment strains, as well as between kitchen environment and patient strains originated either from the same or from different hospitals. Conclusions: The results suggest that hospital kitchens may act as important pathogen hotspots contributing to the circulation of resistant strains in the hospital environment. [ABSTRACT FROM AUTHOR]

Food contamination has emerged as a significant global health concern, posing substantial challenges to the food industry. Bacteria are the primary cause of foodborne diseases. Consequently, it is crucial to develop accurate and efficient sensing platforms to detect foodborne bacteria in food products. Among various detection methods, biosensors have emerged as a promising solution due to their portability, affordability, simplicity, selectivity, sensitivity, and rapidity. Electrospun nanofibers have gained increasing popularity in enhancing biosensor performance. These nanofibers possess a distinctive three-dimensional structure, providing a large surface area and ease of preparation. This review provides an overview of the electrospinning technique, nanofibers and nanofiber-based biosensors. It also explores their mechanisms and applications in the detection of foodborne bacteria such as Salmonella, Listeria monocytogenes (L. monocytogenes), Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Pseudomonas putida (P. putida). [ABSTRACT FROM AUTHOR]

Food is the primary cause for diseases in humans and carries high risk pathogens. Assessment of the safety in foods is needed to validate the presence of pathogenic bacteria. We used colony PCR for this approach to detect foodborne pathogens such as Escherichia coli, Lactobacillus and Bacillus cereus. Suitable primers were selected based on specific gene 1040 for Escherichia coli, gene S2 for Lactobacillus, and gene NVF for Bacillus cereus. Agarose gel electrophoresis is used for the detection of amplified products against a suitable marker. ImageJ is used for DNA band analysis, enabling precise quantification, normalization, and statistical comparisons. These studies have established a promising role in the detection of pathogens in various environmental samples. The insights gained from this study may serve as the foundation for rapid detection of foodborne diseases in the food industry. [ABSTRACT FROM AUTHOR]

Foodborne pathogens' transmission is essential in the spread of antibiotic resistance, and extended-spectrum beta-lactamase-producing Escherichia coli especially threatens public health. E. coli plays an essential role in the resistance to commonly used beta-lactam group antibiotics. Ready-to-eat (RTE) stuffed mussels are among many restaurants and street vendors, presenting potential health risks of food hygiene origin. 200 RTE stuffed mussels were collected from the Asian and European sides of Istanbul and analysed for the presence of E. coli. As a result of PCR analysis, E. coli was detected in 7 (3.5%) samples. An antibiotic susceptibility test was performed using the disc diffusion method to determine ESBL and carbapenem resistance. All isolates were resistant to ampicillin. The double-disk synergy test was performed as an ESBL phenotypic confirmation test, and no phenotypically ESBL-producing E. coli were detected. The bla TEM gene was detected in one isolate (14.2%) by mPCR, but bla CTX-M, bla SHV, and bla OXA genes were not observed. Meropenem and imipenem were used with the disk diffusion method for carbapenem resistance study, and no resistant isolate was found. Carbapenem resistance genes were investigated by monoplex PCR, and bla NDM-1, bla OXA-48, bla VIM, and bla IMP resistance genes were not detected. This is the first report on ESBL-producing E. coli in RTE stuffed mussels in Türkiye, which draws attention to a public health risk. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Diarrheagenic Escherichia coli (DEC) is a kind of foodborne pathogen that poses a significant threat to both food safety and human health. To address the current challenges of high prevalence and difficult subtyping of DEC, this study developed a method that combined multiplex PCR with high-resolution melting (HRM) analysis for subtyping 5 kinds of DEC. The target genes are amplified by multiplex PCR in a single well, and HRM curve analysis was applied for distinct amplicons based on different melting temperature (Tm) values. The method enables discrimination of different DEC types based on characteristic peaks and distinct Tm values in the thermal melting curve. The assay exhibited 100% sensitivity and 100% specificity with a detection limit of 0.5 to 1 ng/μL. The results showed that different DNA concentrations did not influence the subtyping results, demonstrating this method owed high reliability and stability. In addition, the method was also used for the detection and subtyping of DEC in milk. This method streamlines operational procedures, shorts the detection time, and offers a novel tool for subtyping DEC. [ABSTRACT FROM AUTHOR]

Summary: Impacts of aqueous and ethanolic extracts of garlic were investigated in suppressing bacterial growth and biogenic amine (BA) formation by selected foodborne pathogens (Candida albicans, Salmonella paratyphi A, Escherichia coli and Staphylococcus aureus) and fish spoilage bacteria (Enterococcus faecalis, Photobacterium damselae and Pseudomonas luteola). The spread‐plate method was used to monitor bacterial growth in histidine decarboxylase broth (HDB), whereas the rapid high‐performance liquid chromatographic (HPLC) method was used for BA analysis. Bacterial growth and their ammonia and BA production were monitored using HDB. The results showed that bacterial growth on HDB was in the range from 9.13, for P. luteola, to 9.54 log CFU (colony‐forming units) mL−1, for S. aureus and C. albicans. The presence of garlic extracts in HDB resulted considerably in lowering bacterial growth and BA formation (P < 0.05). The highest inhibitory activities of ethanolic and water garlic extracts were obtained for Gram‐positive S. aureus with 1.4 and 1.5 logarithmic reduction on bacterial growth, followed by Gram‐negative Salmonella Paratyphi A and E. coli. Application of garlic extracts, mainly ethanolic ones, showed a significant inhibitory effect on bacterial ammonia production, with 4‐100‐fold lower ammonia accumulation (P < 0.05). Bacteria produced all tested BAs, mainly dopamine, agmatine and tryptamine. The highest levels of histamine and tyramine (61.99 and 36.45 mg L−1) were produced by S. aureus. In the presence of aqueous or ethanolic garlic extracts, putrescine production by E. faecalis was around 110‐fold lower than that of the control group. Results revealed that both garlic extracts are potent antimicrobials that can control the growth of foodborne pathogens and their harmful BA formation. [ABSTRACT FROM AUTHOR]

Introduction: Foodborne infections, which are frequently linked to bacterial contamination, are a serious concern to public health on a global scale. Whether agricultural farming practices help spread genes linked to antibiotic resistance in bacteria associated with humans or animals is a controversial question. Methods: This study applied a long-read Oxford Nanopore MinION-based sequencing to obtain the complete genome sequence of a multi-drug resistant Escherichia coli strain (L1PEag1), isolated from commercial cape gooseberry fruits (Physalis peruviana L.) in Ecuador. Using different genome analysis tools, the serotype, Multi Locus Sequence Typing (MLST), virulence genes, and antimicrobial resistance (AMR) genes of the L1PEag1 isolate were determined. Additionally, in vitro assays were performed to demonstrate functional genes. Results: The complete genome sequence of the L1PEag1 isolate was assembled into a circular chromosome of 4825.722 Kbp and one plasmid of 3.561 Kbp. The L1PEag1 isolate belongs to the B2 phylogroup, sequence type ST1170, and O1:H4 serotype based on in silico genome analysis. The genome contains 4,473 genes, 88 tRNA, 8 5S rRNA, 7 16S rRNA, and 7 23S rRNA. The average GC content is 50.58%. The specific annotation consisted of 4,439 and 3,723 genes annotated with KEEG and COG respectively, 3 intact prophage regions, 23 genomic islands (GIs), and 4 insertion sequences (ISs) of the ISAs1 and IS630 families. The L1PEag1 isolate carries 25 virulence genes, and 4 perfect and 51 strict antibiotic resistant gene (ARG) regions based on VirulenceFinder and RGI annotation. Besides, the in vitro antibiotic profile indicated resistance to kanamycin (K30), azithromycin (AZM15), clindamycin (DA2), novobiocin (NV30), amikacin (AMK30), and other antibiotics. The L1PEag1 isolate was predicted as a human pathogen, matching 464 protein families (0.934 likelihood). Conclusion: Our work emphasizes the necessity of monitoring environmental antibiotic resistance, particularly in commercial settings to contribute to develop early mitigation techniques for dealing with resistance diffusion. [ABSTRACT FROM AUTHOR]

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Gut microbiota is a diverse community of microorganisms that constantly work to protect the gut against pathogens. Salmonella stands out as a notorious foodborne pathogen that interacts with gut microbes, causing an imbalance in the overall composition of microbiota and leading to dysbiosis. This review focuses on the interactions between Salmonella and the key commensal bacteria such as E. coli, Lactobacillus, Clostridium, Akkermansia, and Bacteroides. The review highlights the role of these gut bacteria and their synergy in combating Salmonella through several mechanistic interactions. These include the production of siderophores, which compete with Salmonella for essential iron; the synthesis of short-chain fatty acids (SCFAs), which exert antimicrobial effects and modulate the gut environment; the secretion of bacteriocins, which directly inhibit Salmonella growth; and the modulation of cytokine responses, which influences the host's immune reaction to infection. While much research has explored Salmonella, this review aims to better understand how specific gut bacteria engage with the pathogen, revealing distinct defense mechanisms tailored to each species and how their synergy may lead to enhanced protection against Salmonella. Furthermore, the combination of these commensal bacteria could offer promising avenues for bacteria-mediated therapy during Salmonella-induced gut infections in the future. [ABSTRACT FROM AUTHOR]

Ensuring the microbiological safety of food products is majorly important to regulatory agencies, producers, and consumers. This study aimed to examine the effects of three different antimicrobial agents, including chitosan (CH), mastic oil (M), and citric acid (CA), individually or as a combination, against Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes (artificially inoculated) in Guacamole, a ready-to-eat (RTE) avocado-based salad. The Guacamole samples included untreated samples, designated as CNL, and samples treated as follows: CA 0.15% and CA 0.30% with citric acid added at 0.15% and 0.30% v/w; CH 0.5% and CH 1% with chitosan at 0.5 and 1% v/w; M 0.2% and M 0.4% with mastic essential oil (EO) at 0.2% and 0.4% v/w; CACH with CA 0.30% and CH 1% v/w; CAM with CA 0.30% and M 0.4% v/w; CHM with CH 1% and M 0.4% v/w; and CACHM with CA 0.30%, CH 1%, and M 0.4% v/w. Microbiological evaluation, monitoring of the pH values, and proximate analyses (moisture, fat, protein, ash, and water activity) were performed at different time intervals (days 0, 1, 3, 5, and 7) at two storage temperatures (4 and 10 °C). Antimicrobial treatments, particularly CH 1% and CACHM, effectively (p < 0.05) reduced Salmonella spp. and E. coli O157:H7 populations at 4 °C, while CACHM showed the most efficacy against L. monocytogenes. However, at 10 °C, antimicrobials had limited impact, and the bacterial counts exhibited an increasing trend during storage. The pH values in the avocado-based salad samples showed, in general, higher decreases at 10 compared to 4 °C, with the CHM combination showing the highest antimicrobial effect. [ABSTRACT FROM AUTHOR]

Objectives: Much has been written about the utility of genomic databases to public health. Within food safety these databases contain data from two types of isolates—those from patients (i.e., clinical) and those from non-clinical sources (e.g., a food manufacturing environment). A genetic match between isolates from these sources represents a signal of interest. We investigate the match rate within three large genomic databases (Listeria monocytogenes, Escherichia coli, and Salmonella) and the smaller Cronobacter database; the databases are part of the Pathogen Detection project at NCBI (National Center for Biotechnology Information). Results: Currently, the match rate of clinical isolates to non-clinical isolates is 33% for L. monocytogenes, 46% for Salmonella, and 7% for E. coli. These match rates are associated with several database features including the diversity of the organism, the database size, and the proportion of non-clinical BioSamples. Modeling match rate via logistic regression showed relatively good performance. Our prediction model illustrates the importance of populating databases with non-clinical isolates to better identify a match for clinical samples. Such information should help public health officials prioritize surveillance strategies and show the critical need to populate fledgling databases (e.g., Cronobacter sakazakii). [ABSTRACT FROM AUTHOR]

Access to safe and nutritious food is critical for maintaining life and supporting good health. Eating food that is contaminated with pathogens leads to serious diseases ranging from diarrhea to cancer. Many foodborne infections can cause long-term impairment or even death. Hence, early detection of foodborne pathogens such as pathogenic Escherichia coli strains is essential for public safety. Conventional methods for detecting these bacteria are based on culturing on selective media and following standard biochemical identification. Despite their accuracy, these methods are time-consuming. PCR-based detection of pathogens relies on sophisticated equipment and specialized technicians which are difficult to find in areas with limited resources. Whereas CRISPR technology is more specific and sensitive for identifying pathogenic bacteria because it employs programmable CRISPR-Cas systems that target particular DNA sequences, minimizing nonspecific binding and cross-reactivity. In this project, a robust detection method based on CRISPR-Cas12a sensing was developed, which is rapid, sensitive and specific for detection of pathogenic E. coli isolates that were collected from the fecal samples from adult goats from 17 farms in Tennessee. Detection reaction contained amplified PCR products for the pathogenic regions, reporter probe, Cas12a enzyme, and crRNA specific to three pathogenic genes--stx1, stx2, and hlyA. The CRISPR reaction with the pathogenic bacteria emitted fluorescence when excited under UV light. To evaluate the detection sensitivity and specificity of this assay, its results were compared with PCR based detection assay. Both methods resulted in similar results for the same samples. This technique is very precise, highly sensitive, quick, cost effective, and easy to use, and can easily overcome the limitations of the present detection methods. This project can result in a versatile detection method that is easily adaptable for rapid response in the detection and surveillance of diseases that pose large-scale biosecurity threats to human health, and plant and animal production. [ABSTRACT FROM AUTHOR]

Bacteriophages (phages) have gained considerable attention as effective antimicrobial agents that infect and kill pathogenic bacteria. Based on this feature, phages have been increasingly used to achieve food safety. They are stored in a medium or buffer to ensure stability; however, they cannot be directly applied to food under these conditions due to reasons such as regulatory considerations and concerns about marketability. This study developed a stabilizing solution that allowed the maintenance of phage activity for extended periods at room temperature while being directly applicable to food. The stability of phages stored in distilled water was relatively low. However, adding a stabilizer composed of sugars and salts improved the survival rates of phages significantly, resulting in stability for up to 48 weeks at room temperature. When Escherichia coli O157:H7-contaminated vegetables were washed with tap water containing phages, the phages reduced the pathogenic E. coli count by over 90% compared with washing with tap water alone. Additionally, when pathogenic E. coli-contaminated vegetables were placed in a phage-coated container and exposed to water, the coating of the container dissolved, releasing phages and lysing the pathogenic E. coli. This led to a significant 90% reduction in pathogenic E. coli contamination compared to that after water rinsing. These results suggest an effective and economical method for maintaining phage activity and establishing the potential for commercialization through application in the food industry. [ABSTRACT FROM AUTHOR]

Summary: The growing consumption of untreated juices has increased the outbreaks related to Salmonella spp., Escherichia coli O157:H7 and Listeria monocytogenes. Although these pathogens are not in favourable conditions in fruit juices, cases of survival in acidic environments have been reported in fruit and vegetable juices. Thus, this study has evaluated the microbiological quality (total aerobic mesophilic microorganisms (TAM), moulds and yeasts, total coliforms (TC) and E. coli populations) and investigated the occurrence of foodborne pathogens (Salmonella spp. and L. monocytogenes) in 100 fresh (blended) and self‐service (monovarietal) untreated juices. Concerning the obtained results, pH was higher for fresh juices than for self‐service juices. The results showed great variability in TAM, moulds and yeasts and TC populations. For TAM, the results ranged from 1.7 to 7.4 log cfu mL−1. Values for moulds and yeasts, ranged from below detection limit (<10 cfu mL−1) to 5.9 log cfu mL−1. And for TC, results went from below detection limit (<1 cfu mL−1) to 4.4 log cfu mL−1. However, significant differences were only observed between the two types of samples in TC, being higher in fresh juices than in self‐service juices. For E. coli enumeration, all the samples were below the detection limit (1 cfu mL−1). Finally, no Salmonella spp. or L. monocytogenes were detected in 25 mL of sample. All analysed samples complied the requirements from European regulation. [ABSTRACT FROM AUTHOR]

Introduction: In Japan, sashimi, a distinctive and straightforward meal of fresh fish, is frequently offered for dinner with family or at restaurants. Since sashimi is made from raw tuna loin, infections and spoiling microorganisms can readily damage it, especially if it is served without refrigeration. In addition to ice, novel preservatives need to be researched to prevent the growth of harmful and histamine-producing microbes. Carbonyl, phenols from burning coconut shells, and organic acids are among the antibacterial substances found in liquid smoke (LS). However, more study on liquid smoke nano-encapsulation is needed because there is a lack of evidence about the physicochemical properties of LS. Aims: The goal of the study was to determine the production process of liquid smoke nano-encapsulation (LSN), the level of total histamine in LSN-coated sashimi stored at room temperature, and the effectiveness of LSN against pathogenic microorganisms. Materials and Methods: The following parameters were measured: pH levels, water content, Salmonella, E. coli, total microbial count (TPC), histamine concentration, and antibacterial inhibitory action. Results: The findings demonstrated that LSN with maltodextrin: sago flour: 1% LS ratio of 10: 1: 5 effectively inhibited the growth of E. coli and Salmonella and decreased the amount of histamine in sashimi that was refrigerated for ten days. Conclusions: LSN was effective in preventing the growth of pathogenic bacteria and reducing the histamine content in tuna sashimi. [ABSTRACT FROM AUTHOR]

Kishk is a traditional dry fermented dairy product prepared from a mixture of salted sour butter milk or yoghurt with wheat grains. The goal of this study was to evaluate the microbiological quality, together with isolation and identification of LAB from kishk and assessed their protective effects against E. coli and Pseudomonas aeruginosa in vitro and in vivo. One hundred samples of kishk were randomly obtained from farmers' houses and food stores in the Assiut governorate, Egypt. Total viable count and, total yeasts and molds were performed by plating the samples on selective media. Further, LAB were isolated on de Man Rogosa and Sharpe (MRS) agar and identified by biochemical tests. The antagonistic effect of the obtained LAB was evaluated against two of foodborne pathogens (E. coli and Pseudomonas aeruginosa) in vitro using well diffusion method and in vivo after inoculation in cow's milk. The average total bacterial and yeasts and molds counts were 8.13±0.09 and 2.92±0.16 log10 CFU/g, respectively. Based on phenotypical examination, LAB were identified and classified into three groups namely Lactobacillus, Leuconostoc and Lactococcus. Notably, LAB had more inhibitory activity against E. coli in comparison to Pseudomonas aeruginosa in vitro. However, there was no changes in the mean count of the tested organisms versus control group after inoculation in milk. This study revealed that kishk contain LAB bacteria that have antagonistic properties on E. coli and Pseudomonas aeruginosa. Hence, kishk could be a useful candidate for human health. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 (E. coli O157:H7) is a foodborne pathogenic microorganism that is commonly found in the environment and poses a significant threat to human health, public safety, and economic stability worldwide. Thus, early detection is essential for E. coli O157:H7 control. In recent years, a series of E. coli O157:H7 detection methods have been developed, but the sensitivity and portability of the methods still need improvement. Therefore, in this study, a rapid and efficient testing platform based on the CRISPR/Cas12a cleavage reaction was constructed. Through the integration of recombinant polymerase amplification and lateral flow chromatography, we established a dual-interpretation-mode detection platform based on CRISPR/Cas12a-derived fluorescence and lateral flow chromatography for the detection of E. coli O157:H7. For the fluorescence detection method, the limits of detection (LODs) of genomic DNA and E. coli O157:H7 were 1.8 fg/µL and 2.4 CFU/mL, respectively, within 40 min. Conversely, for the lateral flow detection method, LODs of 1.8 fg/µL and 2.4 × 102 CFU/mL were achieved for genomic DNA and E. coli O157:H7, respectively, within 45 min. This detection strategy offered higher sensitivity and lower equipment requirements than industry standards. In conclusion, the established platform showed excellent specificity and strong universality. Modifying the target gene and its primers can broaden the platform's applicability to detect various other foodborne pathogens. [ABSTRACT FROM AUTHOR]

Introduction: Kefir beverage has beneficial microorganisms that have healthgiving properties; therefore, they have a good potential to be probiotic. This study evaluated the probiotic potential, technological, and safety characteristics of Enterococcus faecalis, Lactococcus lactis, and Pichia fermentans isolated from traditional kefir beverages. Method: First, isolates were evaluated in terms of resistance to acid, alkali, bile salts, trypsin, and pepsin of the gastrointestinal tract. The auto-aggregation and co-aggregation ability of isolates were measured using spectrophotometry. Antimicrobial activities were assayed against important food-borne pathogens using the agar well diffusion method. Moreover, gamma-aminobutyric acid (GABA) production was investigated by thin-layer chromatography (TLC). Result: Among the isolates, P. fermentans had an 85% total survival rate, but its amount reached below 6 log CFU/ml which is considered non-resistant, and it showed the highest auto-aggregation (74.67%). Moreover, only L. lactis showed antimicrobial activity and had the highest co-aggregation with E. coli PTCC 1338 (54.33%) and L. monocytogenes ATCC 7644 (78%). Finally, an evaluation of the technological and safety characteristics of the strains showed that the strains produced GABA and were safe. Discussion: Although the isolates were not resistant to the gastrointestinal tract, their supernatant contained valuable natural compounds, including antioxidants, GABA, and antimicrobials, which can be used to produce functional foods and medicines. In addition, other approaches, such as increasing the initial number of strains, using foods as carriers of isolates, and encapsulating the isolates, can effectively increase the survivability of isolates in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Since ancient times, humans have learned to use fire and other heating methods to fight against dangerous pathogens, like cooking raw food, sterilizing surgical tools, and disinfecting other pathogen transmission media. However, it remains difficult for current heating methods to achieve extremely fast and highly efficient sterilization simultaneously. Herein, an ultrafast and uniform heating‐based strategy with outstanding bactericidal performance is proposed. Ultra‐precise laser manufacturing is used to fabricate the Joule heater which can be rapidly heated to 90 °C in 5 s with less than 1 °C fluctuation in a large area by real‐time temperature feedback control. An over 98% bactericidal efficiency on S. aureus for 30 s and on E. coli for merely 5 s is shown. The heating strategy shows a 360 times faster acceleration compared to the commonly used steam sterilization from the suggested guidelines by the Centers for Disease Control and Prevention (CDC), indicating that high temperatures with short duration can effectively disinfect microorganisms. As a proof of concept, this heating strategy can be widely applied to sterilizing cash and various objects to help protect the public from bacteria in daily life. [ABSTRACT FROM AUTHOR]

Food borne diseases are an important public health problem has major impacts on human health, also affect trade and economic issues. Developing microbial cultures to detect foodborne pathogens is time-consuming and expensive. The aim of this study is to develop a multiplex (mPCR) method for the simultaneous detection of Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella enteritidis. Buffered peptone water (BPW) was used as pre-enrichment. Simplex and multiplex PCR settings were optimized and applied to both pure co-cultures and artificially inoculated ready-to-eat food samples (falafel and chicken nugget). The four microorganisms could be detected individually and in enrichment media artificially inoculated at 101 CFU/mL by mPCR. In conclusion, the individual and combined growth of E. coli, S. enterica, S. aureus and, L. monocytogenes with low levels of contamination in the presence of food matrices such as falafel and chicken nuggets is effectively supported by BPW broth as co-culture medium before mPCR detection. The proposed protocol for pre-enrichment of E. coli, S. enterica, S. aureus and, L. monocytogenes in takes approximately 34 hours, compared to culture methods that require at least 7 days. This notably reduces analysis time, effort, and cost. [ABSTRACT FROM AUTHOR]

Background: Saum is a very important traditional food item of the Mizo society in Mizoram, North East India; but there is scanty scientific study and reports on Saum. The present study has been conducted to study and compare the prevalence of E. coli in Saum from three different storage places such as storage/keeping Saum under the sun (24-38°C) during hot part of the day, inside the refrigerator (3-4°C) and near the cooking fire (30-50°C) at home. Methods: The study was conducted from May, 2022 to November, 2022. A total of 105 Saum samples were collected from three different storage places comprising of 35 samples from each storage places and then analysed for the presence of foodborne pathogen E. coli and it's virulence genes (stx1, stx2, elt, est genes) by conventional method and PCR. All the E. coli isolates were subjected to 12 different antibiotics for antimicrobial resistance pattern by disc diffusion method. Result: The overall prevalence of E. coli from 105 samples was 7.62% (8/105) comprising of 5.71% (2/35) from the storage place under the sun, 2.86% (1/35) from the refrigerator and 14.29% (5/35) near the cooking fire and no presence of virulence genes of E. coli was detected in the present study. The antimicrobial resistance pattern of all the 8 E. coli isolates showed the highest resistance to Cefazolin (100%) followed by Imipenem (37.5%). The present work will be a complementary contribution among Mizo society to know the best and safest storage places of Saum in regards to public health point of view. [ABSTRACT FROM AUTHOR]

The prevalence and impact of antibiotic-resistant pathogens transmitted through food, particularly street-vended foods, is becoming a major public health concern. Although a significant proportion of the urban population in developing countries consumes street-vended foods, the role of these foods in spreading antibiotic resistance has been rarely investigated. In this study, 50 bacterial isolates were obtained from 25 samples representing five categories of street-vended foods: Phuchka, Chatpati, Sausage, Bun, and Salad. The IMVIC test revealed a notably high occurrence of Escherichia coli (n=32) within the collected samples. Three representative isolates were selected for molecular identification using DNA sequencing of 16S rDNA. They were identified as Klebsiella oxytoca, Burkholderia fungorum, and Serratia nematodiphila. The antibiotic susceptibility of the identified isolates (n=35) was investigated using twelve antibiotics following the Kirby-Bauer disk diffusion method. Around 65.63% of the E. coli isolates (n=21) exhibited multidrug resistance. Double Disc Synergy Test (DDST) and Phenotypic Confirmatory Disk Diffusion Test (PCDDT) confirmed ESBL production of Eight multidrugresistant E. coli isolates (38.09%). The multiple antibiotic resistance (MAR) index showed that 22 E. coli isolates had MAR above 0.2, with resistance mostly against oxacillin, ampicillin, and cefuroxime. The Klebsiella oxytoca isolate showed multidrug resistance viz., ampicillin, oxacillin, cefuroxime, and kanamycin. The Burkholderia fungorum isolate showed no distinct inhibition zone against ampicillin and chloramphenicol. Additionally, the Serratia nematodiphila isolate showed no distinct inhibition zone against three antibiotics, including ampicillin, oxacillin, and cefuroxime. These findings might contribute to the knowledge of emerging antibioticresistant foodborne pathogens and raise concerns about the safety of street-vended foods in Bangladesh. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) can produce peptides known as bacteriocins with antagonistic activity against foodborne pathogens. The potential of LAB isolated from the surface of jalapeno peppers to produce bacteriocins with antagonistic activity against Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella Typhimurium was evaluated. Previously isolated LAB strains were reactivated, and their cell-free supernatants (CFSs) were evaluated. Out of 390 reactivated strains, 60 produced bacteriocin-like inhibitory substances (BLIS) since their antagonistic activity was lost after proteases addition. Subsequently, 16 BLIS showed heat resistance (HR-BLIS), retaining their bioactivity after heat treatment (121 °C for 15 min). By 16S rRNA gene sequencing and antibiotic susceptibility tests, LAB strains producing HR-BLIS were identified as Enterococcus lactis. Four HR-BLIS exhibited a minimum inhibitory concentration (MIC) of 80 mg/mL against L. monocytogenes. MIC and minimum bactericidal concentration (MBC) of HR-BLIS-67 for S. aureus (MIC = 80 mg/mL; MBC = 320 mg/mL), S. Typhimurium (MIC = 150 mg/mL; MBC = 250 mg/mL), and E. coli O157:H7 (MIC = 250 mg/mL; MBC = 400 mg/mL) were determined. LAB isolated from the surface of jalapeno pepper produced HR-BLIS (possibly enterocin) that exhibited broad-spectrum antagonistic activity against foodborne pathogens; therefore, they are a promising source of natural antimicrobials to ensure food safety. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) strains have emerged as important foodborne pathogens of global public health concern, causing life-threatening diseases. Animals and their products have been documented as important reservoirs for STECs, especially E. coli O157. The aim of this study was to investigate STECs from healthy and diarrhoeic sheep in Sanandaj, Iran. In the current study, a total of 81 sheep faecal samples were taken (22 from diarrhoeic sheep and 59 from healthy sheep). E. coli and subsequently STEC strains was detected according to standard protocol (cultural characterisation and PCR assays). Finally, the frequency of Shiga-toxin producing gene(s) (stx1, stx2), intimin (eaeA) and enterohaemolysin (hlyA) was detected among STEC isolates using duplex PCR. Totally, 42 E. coli were isolated from 81 faecal samples (51.85% contamination). Of these, 34 isolates (80.9%) were identified as STEC patotypes based on Sorbitol-MacConkey (SMAC) medium culturing and also the presence of stx1 and/or stx2. Of these, only 3 isolates (7.1%) were identified as serotype O157:H7 based on PCR assay. In addition, the results showed that STEC bacteria were significantly more prevalent in diarrhoeic samples than in healthy samples (50% vs. 22.1%). Overall, the PCR results showed that 33 (97%), 12 (35.3%) and 8 (23.5%) isolates carried stx1, stx2 and hlyA, respectively. The eaeA gene was not found in any isolate. The number of isolated STEC bacteria in spring (10 isolates) and winter (14 isolates) were significantly higher than those in summer (4 isolates) and autumn (6 isolates) (P=0.039). Also, the number of STEC in diarrhoea samples was significantly higher compared to non-diarrhoea samples (P=0.032). In conclusion, the present study revealed high prevalence rate of STEC including serotype O157:H7 and non-O157:H7 in sheep faeces which highlights the importance of sheep as a reservoir of STEC pathogen in Sanandaj region. Therefore, additional control and preventive measures must be undertaken to control the contamination by this pathogen. [ABSTRACT FROM AUTHOR]

Loop-mediated isothermal amplification, LAMP, is nowadays the most popular isothermal nucleic acid amplification technique, and as such, several commercial, ready-to-use master mixes have flourished. Unfortunately, independent studies to determine their performance are limited. The current study performed an independent evaluation of the existing ready-to-use commercial LAMP master mixes WarmStart® LAMP Kit, LavaLAMP™ DNA Master Mix, Saphir Bst Turbo GreenMaster, OptiGene Fast Master Mix ISO-004, and SynLAMP Mix. To reduce bias, three different genes, namely ttr (Salmonella spp.), rfbE (E. coli O157), and hly (Listeria monocytogenes), were targeted. The comparison was based on amplification speed, performance with decreasing DNA concentrations, and the effect of five typical LAMP reaction additives (betaine, DMSO, pullulan, TMAC, and GuHCl). Significant differences were observed among the different master mixes. OptiGene provided the fastest amplification and showed less detrimental effects associated with the supplements evaluated. Out of the chemicals tested, pullulan provided the best results in terms of amplification speed. It is noteworthy that the different additives impacted the master mixes differently. Overall, the current study provides insights into the performance of commercial LAMP master mixes, which can be of value for the scientific community to better select appropriate reagents when developing new methods. [ABSTRACT FROM AUTHOR]

Introduction: The study into the interplay between foodborne pathogens and human health, particularly their effects on intestinal cells, is crucial. The importance of lactic acid bacteria (LAB) in promoting a healthy balance of gut microbiota, inhibiting harmful bacteria, and supporting overall gastrointestinal health is becoming more apparent. Methods: Our study delved into the impact of fermenting Woodfordia fruticosa (WF), a plant known for its antimicrobial properties against gastrointestinal pathogens, with LAB. We focused on the influence of this fermentation process on the binding of foodborne pathogens to the gut lining and cytokine production, aiming to enhance gut health and control foodborne infections in HT-29 cells. Results and discussion: Post-fermentation, the WF exhibited improved antimicrobial effects when combined with different LAB strains. Remarkably, the LAB-fermented WF (WFLC) substantially decreased the attachment of pathogens such as L. monocytogenes (6.87% ± 0.33%) and V. parahaemolyticus (6.07% ± 0.50%) in comparison to the unfermented control. Furthermore, WFLC was found to upregulate IL-6 production in the presence of pathogens like E. coli O157:H7 (10.6%) and L. monocytogenes (19%), suggesting it may activate immune responses. Thus, LAB-fermented WF emerges as a potential novel strategy for fighting foodborne pathogens, although additional studies are warranted to thoroughly elucidate WF's phytochemical profile and its contribution to these beneficial outcomes. [ABSTRACT FROM AUTHOR]

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Salmonella is a common foodborne pathogen that can cause food poisoning, posing a serious threat to human health. Therefore, quickly, sensitively, and accurately detecting Salmonella is crucial to ensuring food safety. For the Salmonella hilA gene, we designed Recombinase-aided amplification (RAA) primers and dsDNA-specific nuclease (DNase) probes. The ideal primer and probe combination was found when conditions were optimized. Under UV light, a visual Salmonella detection technique (RAA-dsDNase) was developed. Additionally, the RAA-dsDNase was modified to further reduce pollution hazards and simplify operations. One-pot RAA-dsDNase-UV or one-pot RAA-dsDNase-LFD was developed as a Salmonella detection method, using UV or a lateral flow dipstick (LFD) for result observation. Among them, one-pot RAA-dsDNase and one-pot RAA-dsDNase-LFD had detection times of 50 min and 60 min, respectively, for detecting Salmonella genomic DNA. One-pot RAA-dsDNase-UV had a detection limit of 101 copies/μL and 101 CFU/mL, while one-pot RAA-dsDNase-LFD had a sensitivity of 102 copies/μL and 102 CFU/mL. One-pot RAA-dsDNase-UV and one-pot RAA-dsDNase-LFD assays may identify 17 specific Salmonella serovars witho ut causing a cross-reaction with the remaining 8 bacteria, which include E. coli. Furthermore, Salmonella in tissue and milk samples has been reliably detected using both approaches. Overall, the detection method developed in this study can quickly, sensitively, and accurately detect Salmonella, and it is expected to become an important detection tool for the prevention and control of Salmonella in the future. [ABSTRACT FROM AUTHOR]

Various studies have shown that natural colorants, in addition to their coloring attributes, have valuable biological effects such as antioxidant, anti‐inflammation, and anticarcinogenic properties. Moreover, their use as a food colorant can restrict the potential disadvantages of synthetic additives and turn foods into functional products. In this study, in vitro antimicrobial activities of two natural colorants of bixin and curcumin against some important foodborne pathogens: Staphylococcus aureus (S. aureus), Listeria innocua (L. innocua), and Escherichia coli (E. coli) were investigated by disk diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration values were determined by agar dilution and broth microdilution methods. The synergistic activity of the colorants against selected microorganisms was assayed by the checkerboard microdilution method. The results showed that the inhibitory effects of bixin against S. aureus were more pronounced than E. coli and L. innocua. The lowest concentration of curcumin (0.6 mg/mL) in the disk diffusion method was not inhibited by any tested bacteria. However, it was effective at the higher concentrations against three microorganisms, but its diameter of inhibition zones was lower than gentamicin in all concentrations. Synergetic effects were observed by curcumin and bixin combination against S. aureus (FICI ≤ 0.5), but they act as an antagonist against E. coli and L. innocua. The results of the synergy test were confirmed by the isobologram curves. [ABSTRACT FROM AUTHOR]

Foodborne pathogens are a leading cause of mortality worldwide. Therefore, strategies focused on functional foods are urgently required to tackle this issue. As a result, camel milk is one of the most important traditional functional foods since it contains a variety of bioactive components, which all have antimicrobial activity against foodborne pathogens. The study aims to investigate the potential antimicrobial activity of raw camel milk against foodborne pathogens in both in vitro agar well diffusion and infected mice, especially Listeria monocytogenes, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli, particularly in societies that rely on consuming camel milk in its raw form. A total of eighty C57BL/6 mice were divided into ten groups and gavaged with or without camel milk for two consecutive weeks. A blood plasma analysis and serum insulin levels were measured. Histological investigations of the liver, pancreas, kidney, spleen, lung and testicles were also performed. In both in vivo and in vitro studies when compared to other pathogenic bacteria, E. coli was the most affected by raw camel milk, with a significant clear zone of 2.9 ± 0.13 cm in vitro and in all measured parameters in vivo (p < 0.05). As a result, we advocated for further research to improve camel breeding, raise milk yield and extend its reproductive capability as one of the most important farm animals. [ABSTRACT FROM AUTHOR]

Shortwave ultraviolet light (UV-C) disinfection is an emerging technology used to enhance food safety by reducing the pathogen load. Computational fluid dynamics (CFD) served as a numerical simulation tool to calculate the average radiation intensity within a disinfection chamber. The resulting CFD data was employed to estimate the UV-C inactivation kinetic parameters for Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes. Experimental procedures involved irradiating bacterial suspensions with UV-C doses ranging from 0 to 6.028 kJ/m2. The inactivation of S. Typhimurium was described using a log-linear equation, while UV-C survival curves for E. coli O157:H7 and L. monocytogenes were best fitted to Weibull model. Subsequently, the integration of CFD simulations and kinetic parameters enabled the estimation of UV-C doses approaching 6 kJ/m2 for the treatment of fresh-cut 'Tommy Atkins' mangoes inoculated with the mentioned microorganisms. This integrated approach partially predicted the inactivation of pathogens on the surface of mango spears. [ABSTRACT FROM AUTHOR]

Pathogenic Escherichia coli are the most prevalent foodborne bacteria, and their accurate detection in food samples is critical for ensuring food safety. Therefore, a quick technique named viability-qPCR (v-qPCR), which is based on the ability of a selective dye, such as propidium monoazide (PMA), to differentiate between alive and dead cells, has been developed. Despite diverse, successful applications, v-qPCR is impaired by some practical limitations, including the ability of PMA to penetrate the outer membrane of dead Gram-negative bacteria. The objective of this study is to evaluate the ability of lactic acid (LA) to improve PMA penetration and, thus, the efficiency of v-qPCR in detecting the live fraction of pathogens. The pre-treatment of E. coli ATCC 8739 cells with 10 mM LA greatly increased PMA penetration into dead cells compared to conventional PMA-qPCR assay, avoiding false positive results. The limit of detection when using LA-PMA qPCR is 1% viable cells in a mixture of dead and alive cells. The optimized LA-PMA qPCR method was reliably able to detect log 2 CFU/mL culturable E. coli in milk spiked with viable and non-viable bacteria. Lactic acid is cheap, has low toxicity, and can be used to improve the efficiency of the v-qPCR assay, which is economically interesting for larger-scale pathogen detection applications intended for food matrices. [ABSTRACT FROM AUTHOR]

Foodborne zoonosis is a longstanding global issue that limits and continues to threaten the food production industry and public health in several countries. The study's objective was to evaluate the dairy farmers' knowledge, attitudes, and practices about milk-borne pathogens in the Eastern Cape province, South Africa. A total of 139 dairy farmers were interviewed using a semi-structured online questionnaire. The pathogens of interest were Brucella spp., Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Cryptosporidium. Only 20.9% of dairy farmers reported knowledge of Brucella spp. as a milk-borne pathogen. The most known pathogen was E. coli (54.7%), followed by Listeria spp. (41.0%), Staphylococcus spp. (38.8%), and Salmonella spp. (35.3%). In this study, knowledge of milk-borne pathogens was statistically associated (p<0.05) with workplace position. Only a few participants (37.2%) showed knowledge of abortion as an important clinical sign of foodborne pathogens. Also, 84.1% of dairy farmers indicated that they consume unpasteurized milk and sour milk (77%). Some respondents (18.0%) do not believe assisting a cow during calving difficulty without wearing gloves is a risk factor for zoonosis. Knowledge assessment is essential in developing countries that have experienced a foodborne outbreak, such as South Africa. There is an urgent need to educate dairy farmers about milk-borne zoonosis to minimize the threat to food security and public health. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the antimicrobial effect of the combination treatment of high pressure processing (HPP) and mild heat against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes in apple puree. Also, we determined the levels of sub-lethally injured cells according to the treatment condition. Inoculated apple puree was treated at 300 or 400 MPa for up to 7 min at 20, 35, or 50 °C. Increasing the pressure level or treatment temperature resulted in larger reductions of foodborne pathogens. Moreover, the antimicrobial effect of the combination treatment was prominent in apple puree at pH 3.5 than pH 3.8. E. coli O157:H7 and L. monocytogenes exhibited more resistance to the combination treatment with HPP and mild heat than S. Typhimurium. Also, a high proportion of sub-lethally injured E. coli O157:H7 cells was observed. No significant differences in pH, soluble solid contents, and the color of apple puree between control and HPP and mild heat-treated samples were observed during storage for 28 d at 5 °C. This study provides insights into predicting the inactivation patterns of pathogenic bacteria in apple puree by the combination treatment with HPP and mild heat for practical applications. [ABSTRACT FROM AUTHOR]

The presence of antibiotic‐resistant pathogens in food is a serious public health concern nowadays. This study focuses on the isolation and characterization of potentially pathogenic Escherichia coli and antimicrobial‐resistant pathogens in chicken curry and potato smash samples collected from the canteens and cafeteria of Dhaka University in Bangladesh. Isolates were identified by their cultural, morphological, and biochemical tests (motility indole urease test, Kliger's iron agar test, catalase test, oxidase test, methyl red and Voges‐Proskauer tests). The antibiotic susceptibility test was done by the disk diffusion method. The range of total bacterial count in the potato smash and chicken curry samples was from 1.4 × 104 to 1.6 × 108 CFU/g and from 2.4 × 103 to 2.6 × 106 CFU/g, respectively. Escherichia coli, Salmonella, Vibrio, Klebsiella, Citrobacter, Enterobacter, Proteus, Clostridium, Staphylococcus, Streptococcus, Micrococcus, Bacillus, and Sarcina strains were isolated in both samples. Isolates were highly resistant to ampicillin (90.90%) followed by colistin (52.27%), azithromycin (27.27%), and tetracycline 25%. Proteus species had the highest rate of multiple antibiotic resistance (MAR; 62.5%), followed by Citrobacter species (50%). The isolated E. coli strains were further analyzed through PCR assay to detect virulent genes (EPEC: eaeA 229 bp, bfpA 450 bp, ETEC elt 322 bp, EHEC hylA 534 bp, and EIEC ial 320 bp). One E. coli isolate had the eaeA target gene under EPEC pathotypes. Escherichia coli, as a fecal indicator, may indicate fecal contamination or poor and unhygienic food handling. The findings recommend further investigations to identify potential mechanisms of contamination and preventive measures to improve the food safety level in the canteens and restaurants. [ABSTRACT FROM AUTHOR]

Plant-derived flavonoids have excellent bioactivities and applications, especially those from herbs, and it is hypothesized that flavonoids also play an important role in the functions of edible and medicinal Artemisia argyi. Therefore, in the present work, the component and structure of A. argyi leaf flavonoids (AALFs) were characterized, and their antioxidant and antibacterial activities were further investigated. Component determination results showed that the contents of flavonoids, carbohydrates, proteins, polyphenols in AALFs were 90.03 ± 1.37%, 1.24 ± 1.58%, 1.89 ± 1.42% and 6.84 ± 1.13%, respectively. The typical structural units of flavonoids in AALFs were analyzed and verified by ultraviolet visible (UV-VIS) spectroscopy, fourier transform infrared (FT-IR) spectroscopy and Nuclear magnetic resonance (NMR) detection. In vitro antioxidant analysis indicated that AALFs had excellent scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH); ABTS, 2,2′ -azinobis-di-(3-ethyl-benzothiazolin-6-sulfonic acid) diammonium salt (ABTS), hydroxyl and superoxide radicals, and the corresponding 50% inhibitory concentration (IC50) values were 0.176 mg/mL, 0.538 mg/mL, 0.236 mg/mL and 0.192 mg/mL. Meanwhile, disk diffusion assay showed that AALFs could efficiently inhibit the growth profiles of Escherichia coli and Staphylococcus aureus, and the minimum inhibitory concentrations (MICs) were 0.8 mg/mL and 0.65 mg/mL. Results of this work will provide help for utilization of A. argyi leaf and its flavonoids as preservatives to avoid food deterioration and food-borne pathogen spoilage. [ABSTRACT FROM AUTHOR]

Introduction: Integrated crop-livestock systems (ICLS) use animals to graze crop residues or cover crops before planting fresh produce and provide ecosystem services to support organic vegetable production. However, there is a risk of foodborne pathogen transfer to fresh produce because grazing may introduce enteric foodborne pathogens into the soil via animal feces, which may subsequently be transferred to the produce. Methods: To examine the effect of cover crop use and the risk of cover crop grazing on the contamination of soil and produce by foodborne pathogens in ICLS, a three-year (2019-2021) experimental study was conducted in organically managed plots, which were assigned three different treatments (fallow without cover crop or grazing, cover crop without grazing, or cover crop with grazing by sheep) in a maize/tomato rotation. During the three years of the experiment, a total of 184 pre- and post-graze fecal samples and 96 samples of tomatoes were collected to test for foodborne pathogens (Escherichia coli O157, non-O157 Shiga toxin-producing Escherichia coli (STEC), and Listeria (L.) monocytogenes). Soil samples were collected monthly until 126-171 days after grazing (824 in total) to examine the presence of foodborne pathogens, and generic E. coli (MPN/g) was quantified to compare its persistence among the three treatments. Results and Discussion: We did not detect any foodborne pathogens from harvested tomatoes in 2020 and 2021. One non-O157 STEC positive soil sample (0.1%, 1/824) was detected in the fallow treatment, and one L. monocytogenespositive (1.1%, 1/92) was detected from the post-graze fecal samples. When assessing proportions of generic E. coli positive and counts of generic E. coli in the soil samples using mixed effect zero-inflated negative binomial models, soil samples collected in the graze cover crop treatment plot showed significant increases in the counts of generic E. coli until 61-82 days post grazing, but no difference was observed after 96-123 days, compared to the baseline of the fallow treatment. Findings from generic E. coli counts support the use of the United States Department of Agriculture (USDA) National Organic Program (NOP) 90- or 120-day interval rule between applying raw manure and harvesting in organic farming into ICLS. Additionally, we confirmed that commercial organic compost application before cover crop seeding in the winter had no significant effect on the proportions and counts of generic E. coli in the soil of the following growing seasons. This longitudinal field trial confirmed that the effect of sheep grazing on foodborne pathogen contamination in ICLS is minimal but further studies comparing the genetic associations between fecal and soil samples would be necessary to distinguish the source of foodborne pathogen contamination. [ABSTRACT FROM AUTHOR]

IntroductionFoodborne infections, which are frequently linked to bacterial contamination, are a serious concern to public health on a global scale. Whether agricultural farming practices help spread genes linked to antibiotic resistance in bacteria associated with humans or animals is a controversial question.MethodsThis study applied a long–read Oxford Nanopore MinION-based sequencing to obtain the complete genome sequence of a multi-drug resistant Escherichia coli strain (L1PEag1), isolated from commercial cape gooseberry fruits (Physalis peruviana L.) in Ecuador. Using different genome analysis tools, the serotype, Multi Locus Sequence Typing (MLST), virulence genes, and antimicrobial resistance (AMR) genes of the L1PEag1 isolate were determined. Additionally, in vitro assays were performed to demonstrate functional genes.ResultsThe complete genome sequence of the L1PEag1 isolate was assembled into a circular chromosome of 4825.722 Kbp and one plasmid of 3.561 Kbp. The L1PEag1 isolate belongs to the B2 phylogroup, sequence type ST1170, and O1:H4 serotype based on in silico genome analysis. The genome contains 4,473 genes, 88 tRNA, 8 5S rRNA, 7 16S rRNA, and 7 23S rRNA. The average GC content is 50.58%. The specific annotation consisted of 4,439 and 3,723 genes annotated with KEEG and COG respectively, 3 intact prophage regions, 23 genomic islands (GIs), and 4 insertion sequences (ISs) of the ISAs1 and IS630 families. The L1PEag1 isolate carries 25 virulence genes, and 4 perfect and 51 strict antibiotic resistant gene (ARG) regions based on VirulenceFinder and RGI annotation. Besides, the in vitro antibiotic profile indicated resistance to kanamycin (K30), azithromycin (AZM15), clindamycin (DA2), novobiocin (NV30), amikacin (AMK30), and other antibiotics. The L1PEag1 isolate was predicted as a human pathogen, matching 464 protein families (0.934 likelihood).ConclusionOur work emphasizes the necessity of monitoring environmental antibiotic resistance, particularly in commercial settings to contribute to develop early mitigation techniques for dealing with resistance diffusion.

Antibiotic resistance in foodborne pathogens is an increasing threat to global human health. Among the most prevalent antibiotic-resistant bacteria are Salmonella enterica serovar Typhimurium, Campylobacter jejuni and E. coli 0157:H7. Control of these and other pathogens requires innovative approaches, i.e., discovering new molecules that will inactivate them, or render them less virulent without inducing resistance. Recently, several polyphenol molecules have been shown to possess such characteristics. Also, the use of CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) approaches has recently been proposed for such purpose. This review summarizes the main findings regarding the application of both approaches to control the above-mentioned foodborne pathogens by relying on Quorum Sensing interference (Quorum Quenching) mechanisms and highlights the avenues needed for further research. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) and plant extracts have demonstrated inhibitory activity against a wide range of pathogenic bacteria. In this study, the chemical composition of manuka, kanuka, peppermint, thyme, lavender, and feijoa leaf and peel EOs and feijoa peel and leaf extracts were analyzed, and their antimicrobial activity against Escherichia coli, Salmonella enterica Typhimurium, Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes were determined. The results showed that the major compounds varied among different EOs and extracts, with menthol in peppermint EO, thymol and carvacrol in thyme EO, linalool in lavender EO, β‐caryophyllene in feijoa EO, and flavones in feijoa extract being the most prevalent. The study found that while EOs/extracts had antimicrobial activity alone, no individual EO/extract was highly effective against all tested species. Therefore, their combinations were tested to identify those that could broaden the spectrum of activity and act synergistically. The checkerboard method was applied to assess the possible synergism between the paired combinations of EOs/extract. The peppermint/thyme, peppermint/lavender, and peppermint/feijoa peel extract combinations exhibited a synergistic effect against E. coli and L. monocytogenes, with the peppermint/thyme and peppermint/feijoa peel extract combinations being the most effective against all five pathogens. Time‐to‐kill kinetics assays demonstrated that peppermint/thyme and peppermint/feijoa peel extract combinations achieved complete eradication of E. coli within 10–30 min and L. monocytogenes within 4–6 h. This study provides a promising approach to developing a natural alternative for food preservation using synergistic combinations of EOs/extracts, which could potentially reduce the required dosage and broaden their application in food products as natural preservatives. [ABSTRACT FROM AUTHOR]

Flagellum-mediated motility has been suggested to contribute to virulence by allowing bacteria to colonize and spread to new surfaces. In Salmonella enterica and Escherichia coli species, mutants affected by their flagellar motility have shown a reduced ability to form biofilms. While it is known that some species might act as co-aggregation factors for bacterial adhesion, studies of food-related biofilms have been limited to single-species biofilms and short biofilm formation periods. To assess the contribution of flagella and flagellum-based motility to adhesion and biofilm formation, two Salmonella and E. coli mutants with different flagellar phenotypes were produced: the fliC mutants, which do not produce flagella, and the motAB mutants, which are non-motile. The ability of wild-type and mutant strains to form biofilms was compared, and their relative fitness was determined in two-species biofilms with other foodborne pathogens. Our results showed a defective and significant behavior of E. coli in initial surface colonization (p < 0.05), which delayed single-species biofilm formation. Salmonella mutants were not affected by the ability to form biofilm (p > 0.05). Regarding the effect of motility/flagellum absence on bacterial fitness, none of the mutant strains seems to have their relative fitness affected in the presence of a competing species. Although the absence of motility may eventually delay initial colonization, this study suggests that motility is not essential for biofilm formation and does not have a strong impact on bacteria's fitness when a competing species is present. [ABSTRACT FROM AUTHOR]