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Background: The burden of foodborne diseases and antimicrobial resistance carried by key foodborne pathogens in India is unknown due to a lack of an integrated surveillance system at the human-animal interface. Methods: We present data from the WHO-AGISAR (Advisory Group on Integrated Surveillance of Antimicrobial Resistance), India project. Concurrent human and animal sampling was done across a large area across north India. Community-acquired diarrhea cases (n = 1968) of all age groups were included. Cross-sectional sampling of stool/ intestinal contents (n = 487) and meat samples (n = 419) from food-producing animals was done at farms, retail shops, and slaughterhouses. Pathogens were cultured and identified, and antimicrobial susceptibility was performed. Results: Over 80% of diarrhoeal samples were obtained from moderate to severe diarrhea patients, which yielded EAEC (5%), ETEC (4.84%), EPEC (4.32%), and Campylobacter spp. (2%). A high carriage of EPEC (32.11%) and Campylobacter spp. (24.72%) was noted in food animals, but the prevalence of ETEC (2%) and EAEC (1%) was low. Atypical EPEC (aEPEC, 84.52%, p ≤0.0001) were predominant and caused milder diarrhea. All EPEC from animal/poultry were aEPEC. Overall, a very high level of resistance was observed, and the MDR rate ranged from 29.2% in Campylobacter spp., 53.6% in EPEC, and 59.8% in ETEC. Resistance to piperacillin-tazobactam, cefepime, ceftriaxone, and co-trimoxazole was significantly higher in human strains. In contrast, resistance to ciprofloxacin, aminoglycosides, and tetracycline was higher in animal strains, reflecting the corresponding usage in human and animal sectors. ESBL production was commoner in animal isolates than in humans, indicating high use of third-generation cephalosporins in the animal sector. C. hyointestinalis is an emerging zoonotic pathogen, first time reported from India. Conclusion: In one of the most extensive studies from India, a high burden of key foodborne pathogens with MDR and ESBL phenotypes was found in livestock, poultry, and retail meat.

Environmental monitoring programs (EMPs) for food production facilities are useful for verifying general sanitation controls and are recommended as verification measures to ensure that the Hazard Analysis Critical Control Point plan is working effectively. In this study, EMPs for Listeria were conducted at three food production facilities to assess the efficacy of sanitation control and establish effective sanitation control methods. In Facility A, L. monocytogenes was detected in the clean area although in Zone 3, non–food-contact surfaces. To prevent contamination from dirty areas, the cleaning practices in the preparation room were investigated. Normal cleaning combined with disinfection with carbonated hypochlorite water (chlorine concentration, 150 ppm) proved effective. At Facility B, a salad product and its ingredients (pastrami and salami) were positive for L. monocytogenes serotype 3b. The bacterial count was

An online questionnaire was used to investigate behaviors and habits relating to food retrieval by Swedish dumpster divers. Respondents were also asked to share information on their background, reasons for engaging in dumpster diving, and perceptions of potential bacterial hazards associated with the consumption of discarded foods. The questionnaire was mainly distributed to Swedish social media groups focusing on dumpster diving, and a total of 92 responses were received. The most common reason given for engaging in dumpster diving was to reduce food waste and associated negative environmental impacts (60%, n = 55). Many of the respondents (65%) had completed university education, and around three-quarters (73%) had some form of employment or were enrolled in studies. Half the respondents (52%, n = 48) perceived a risk of falling ill after consuming food obtained through dumpster diving, but very few (2%) reported they had been made ill by food they had picked up from dumpsters. Around one-fifth (22%) of the respondents did not know of any bacteria that could cause foodborne infections or food poisoning. Salmonella was mentioned by 35% of the respondents, while Listeria was mentioned by 18%. The respondents reported employing various techniques to reduce the risk of encountering harmful microbiological agents, for example, rinsing their food retrievals or discarding food that appeared spoiled. These are novel findings on dumpster divers’ perceptions of perceived health risks and the strategies they use to mitigate such risks with food obtained through dumpster diving.

Studies on the system-scale pathogenesis of Listeria monocytogenes infection have classically focused on its ability to colonize in the intestines following an exposure event. However, despite this, many of the most dangerous complications arising from L. monocytogenes infection are observed days, weeks, or months after exposure, resulting indirectly from bacteria escaping this intestinal colonization hub and invading other organs. Over time, findings of various individual phenomena observed during systemic infection have accumulated, including a shift away from the principal route of intestinal dissemination, delays in bacterial colonization of the central nervous system, differing bacterial flux rates across organs, and multi-stability of bacterial population levels. To further our quantitative understanding of foodborne bacterial infection dynamics, a compartmental model of systemic infection that synthesizes these findings is proposed. Under parameterization to infection in BALB/c mice, the model is used to show a substantial decrease in bacterial populations resulting from dissemination through the mesenteric lymph nodes, as compared to the portal vein, when controlling for the number of bacteria passing through each route. Due to the compartmental nature of this model, we anticipate that this result may be paralleled in other microbes which make use of these pathways to escape the intestinal environment. Additionally, we predict thresholds for intestinal dissemination along each of these routes, which must be surpassed to induce systemic infection, and describe how these thresholds change over time. Supplementarily, logistic curves are fitted to synthetic data as a means of robustly quantifying the dose-response relationship beyond the intestinal barrier., Competing Interests: Declaration of competing interest The author declares no competing interests that could have influenced the content or production of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Environmental monitoring programs (EMPs) for food production facilities are useful for verifying general sanitation controls and are recommended as verification measures to ensure that the Hazard Analysis Critical Control Point plan is working effectively. In this study, EMPs for Listeria were conducted at three food production facilities to assess the efficacy of sanitation control and establish effective sanitation control methods. In Facility A, L. monocytogenes was detected in the clean area although in Zone 3, non-food-contact surfaces. To prevent contamination from dirty areas, the cleaning practices in the preparation room were investigated. Normal cleaning combined with disinfection with carbonated hypochlorite water (chlorine concentration, 150 ppm) proved effective. At Facility B, a salad product and its ingredients (pastrami and salami) were positive for L. monocytogenes serotype 3b. The bacterial count was <10/g in all samples. However, when inoculated with L. monocytogenes isolates, the growth of approximately 2 log cfu/g was observed on pastrami after 48 h of incubation at 10°C. The ingredients were commercially purchased blocks that were sliced in a slicer at Facility B and used as salad toppings. Because both unopened blocks were negative for L. monocytogenes, contamination of the slicer was suspected. Sampling of the slicer revealed that contamination by L. monocytogenes serotype 3b was more extensive after use than before use. Therefore, the slicer was disassembled, cleaned, and disinfected thoroughly. In Facility C, L. monocytogenes serotype 4b (4e) was detected in all the dirty, semiclean, and clean areas. The strain was also isolated from the wheels of a smoking cart transported across the zones. Therefore, efforts were made to frequently clean and disinfect the cart. EMPs revealed the presence of Listeria in each facility and allowed remedial measures to be undertaken. Continued monitoring and Plan-Do-Check-Act cycles were considered desirable., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This work was supported by a Grant-in-Aid for Research Activity Start-up (grant number: JP21K21174), the Japan Society for the Promotion of Science., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

As a major threat to food safety due to their pathogenicity, foodborne bacteria have received much attention. In this paper, we present a one-step and wash-free microfluidic biosensor platform by smartphone for simultaneous multiple foodborne bacteria target single-stranded DNA (ssDNA) detection. This technology is based on the fluorescence resonance energy transfer (FRET) between the graphene oxide (GO) and fluorescence molecules modified capture ssDNA of the target bacteria ssDNA (ctDNA) which were coated on the microfluidic chips. The fluorescence recovery was recorded by a smartphone fluorescent detector. With an optimal analytical performance, the platform realized the detection of four kinds of bacteria ssDNA simultaneously within 5 min, with the limits of detection (LODs) of 0.17, 0.18, 0.27, and 0.17 nM, respectively. And the throughput analysis of trace amounts of foodborne bacteria ssDNA in milk and water samples were successfully detected. This one-step and wash-free microfluidic biosensor can be used as a tool for food safety analysis., Competing Interests: Declaration of competing interest The authors 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 © 2022 Elsevier B.V. All rights reserved.)

An online questionnaire was used to investigate behaviors and habits relating to food retrieval by Swedish dumpster divers. Respondents were also asked to share information on their background, reasons for engaging in dumpster diving, and perceptions of potential bacterial hazards associated with the consumption of discarded foods. The questionnaire was mainly distributed to Swedish social media groups focusing on dumpster diving, and a total of 92 responses were received. The most common reason given for engaging in dumpster diving was to reduce food waste and associated negative environmental impacts (60%, n = 55). Many of the respondents (65%) had completed university education, and around three-quarters (73%) had some form of employment or were enrolled in studies. Half the respondents (52%, n = 48) perceived a risk of falling ill after consuming food obtained through dumpster diving, but very few (2%) reported they had been made ill by food they had picked up from dumpsters. Around one-fifth (22%) of the respondents did not know of any bacteria that could cause foodborne infections or food poisoning. Salmonella was mentioned by 35% of the respondents, while Listeria was mentioned by 18%. The respondents reported employing various techniques to reduce the risk of encountering harmful microbiological agents, for example, rinsing their food retrievals or discarding food that appeared spoiled. These are novel findings on dumpster divers' perceptions of perceived health risks and the strategies they use to mitigate such risks with food obtained through dumpster diving., Competing Interests: Declaration of Competing Interest The authors 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 © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Rapid and sensitive detection of multiple foodborne bacteria without DNA amplification is still challenging. Here, we proposed an immunochromatographic assay (ICA) with multiplex analysis ability and high sensitivity for direct detection of bacteria in real food samples, based on an improved surface-enhanced Raman scattering (SERS) sensing strategy. Multifunctional Au shell-coated graphene oxide nanosheets (GO@Au) were fabricated and for the first time introduced into the ICA system as a two-dimensional film-like SERS label, which possessed huge surface area, excellent stability, and superior SERS activity. Different from the conventional spherical nanotags, the antibody-conjugated GO@Au nanosheet effectively and rapidly adhered to bacterial cells, improved the dispersibility of bacteria-nanolabel complexes on the ICA strips, and provided numerous stable hotspots for SERS signal enhancement. The combination of GO@Au labels and the ICA system achieved the multiplex and ultrasensitive determination of three major foodborne pathogens, namely, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella typhimurium, in a single test, with low detection limits (8, 10, and 10 cells/mL) and short detection time (20 min). The proposed biosensor demonstrated high stability and good accuracy in various food samples and is thus a promising tool for the rapid identification of bacteria., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Abstract: Low-temperature and longtime (LT-LT) cooking, also known as sous vide cooking, is the process in which meat is sealed in a bag and cooked in hot water at a relatively low temperature of around 60°C. This cooking method has increased in popularity, and low-temperature cookers for home use are now commercially available. However, after LT-LT cooking, if any foodborne bacteria remain, they could cause infection and foodborne illnesses. Therefore, in the present study, the aim was to determine the appropriate LT-LT cooking methods for chicken by assessing temperature changes and studying the bacteria in LT-LT-cooked chicken meat. At set cooking temperatures of 60 and 65°C, the temperatures were measured at the surface and in the centers of single- and double-layer samples of 300 g of chicken breast meat. The times required to reach 50°C were 5 to 14 min at the surface, 25 min in the center of the single-layer sample, and 33 to 35 min in the center of the double-layer sample. The time taken to reach 50°C was fastest in the surface of single-layer chicken meat, followed by the center of single-layer and double-layer chicken meat (P < 0.05). When the meat was LT-LT cooked at 60 and 65°C for 60 min, color changes in the meat and heating of the meat were observed all the way to the interior. Campylobacter jejuni, Salmonella O7, and Listeria monocytogenes were inoculated into chicken breasts, which were then cooked at set temperatures of 60 and 65°C for 15, 30, 60, 90, and 120 min. C. jejuni survived for up to 30 min of cooking, Salmonella O7 survived for up to 60 min of cooking at 60°C and 30 min at 65°C, and L. monocytogenes survived for up to 90 min of cooking at 60°C and 60 min at 65°C. Thus, to prevent infection and illness caused by the three tested bacteria species, LT-LT cooking for 120 min at 60°C and 90 min at 65°C is recommended., (Copyright ©, International Association for Food Protection.)

A lab-on-a-tube biosensor was established to rapidly, sensitively and automatically detect foodborne bacteria through a rotatable Halbach magnet to form and rotate magnetic nanobead (MNB) chains for specific isolation of target bacteria, gold@platinum nanocatalysts (Au@PtNCs) to label target bacteria for efficient amplification of detection signal and Raspberry Pi App to collect and analyze the image of catalysate. First, the glass tube was successively preloaded with the mixture of MNBs, sample and Au@PtNCs, the washing buffer (skim milk) and the substrate (hydrogen peroxide-3,30,5,50-tetramethylbenzidine), and they were separated by air gaps. After the tube was placed on the biosensor, the MNB chains were stably formed and continuously rotated using the Halbach magnet and the mixture was moved back and forth using a programmable peristaltic pump, thus making the formation of MNB-bacteria-Au@PtNCs complexes. After the washing buffer was moved to wash the complexes, the substrate was then moved to resuspend the complexes, resulting in the catalytic reaction that changed the color of the substrate. Finally, the catalysate was moved to the designated area, the image of which was analyzed by the Raspberry Pi App to quantitatively determine the concentration of bacteria in the samples. This biosensor was able to detect Salmonella in spiked chicken samples in 1 h with lower detection limit of 8 CFU/50 μL and a recovery from 88.96% to 99.74%. This biosensor based on a single tube is very promising to automatically detect foodborne bacteria due to its low cost, high integration and simple operation., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Abstract: Chicha morada, also known as purple corn drink (PCD), is a traditional noncarbonated beverage commonly prepared at homes and restaurants in Peru. However, in recent years, it is being produced at an industrial scale aiming to extend its shelf life, expand its marketing, and make it known worldwide. Traditionally, this beverage, whose main component is purple corn (Zea mays L.), was made and consumed quickly and in some cases, stored under refrigeration until consumption, but never beyond 24 to 48 h. With its industrialization, factories are presented with challenges to design and provide adequate protection of the beverage, assuring its quality and safety. Although its production at an industrial level is similar to that of other noncarbonated drinks containing fruit juice, several processing factors could affect the microbiological stability desired for this beverage, such as the storage of the purple corn drink extract. In this document, a critical review of the production process (raw materials, production stages, and forms of commercialization) that can directly affect the contamination of the beverage is made. Recommendations are made for improving the control points in the industrial process and to avoid potential microbiological problems., (Copyright ©, International Association for Food Protection.)

This study determined the efficacy of UV-C as a decontamination process against some foodborne bacteria in dried whole black peppercorns. Artificially-inoculated Salmonella enterica, Escherichia coli O157:H7, Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus were subjected to UV-C with a surface irradiance of 0.43 mW/cm 2 and were all found to exhibit a biphasic inactivation pattern with fast log-linear inactivation followed by a tail. Total log reductions (TLR) ranged from 1.92 (S. aureus) to 3.60 log CFU/g (E. coli O157:H7). Increasing the lamp number from 1 to 5 also linearly (R 2  = 0.98) increased the surface irradiance from 0.43 to 1.70 and the TLR of the most resistant S. aureus from 1.92 to 2.62 log CFU/g. Quality evaluation showed very small, variable changes in color coordinates, which were not detected by a same/different test involving a 50-member sensory evaluation panel. Mercury deposition was not detected after a maximum exposure time of 90 min to 0.43 and 1.70 mW/cm 2 . Finally small, non-significant changes in the innate bacterial microflora of the black peppercorns were determined after 90 min-treatment using 1 lamp and 5 lamps, emphasizing the limitation of utility of UV-C as additional decontamination process for post-process-introduced microorganisms. Good Manufacturing Practices throughout the dried black peppercorn manufacturing process were recommended., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Abstract: Naturally occurring monoglyceride esters of fatty acids have been associated with a broad spectrum of antimicrobial activities. We used an automated turbidimetric method to measure the MIC and assess the antimicrobial activity of five monoglycerides (monocaprin, monolaurin, monomyristin, monopalmitin, and monostearin) against pathogenic strains of Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. The antibacterial activity of monocaprin was highest because its carbon chain is shorter than those of other monoglycerides. The MICs of monocaprin against S. aureus, B. subtilis, P. aeruginosa, and E. coli were 0.32, 0.32, 2.5, and 2.5 mg/mL, respectively. Monocaprin had antibacterial activity under neutral and alkaline conditions (pH 7.0 to 9.0) but had no inhibitory effect on S. aureus, B. subtilis, and E. coli under weakly acidic conditions (pH 6.0). The antibacterial mechanism of monocaprin against gram-positive strains (S. aureus and B. subtilis) resulted from destruction of the cell membrane. In contrast, the antibacterial activity of monocaprin against gram-negative strains (P. aeruginosa and E. coli) was attributed to damage to lipopolysaccharides in the cell walls. Because of its inhibitory effect on both gram-positive and gram-negative bacteria, monocaprin could be used as an antibacterial additive in the food industry., (Copyright ©, International Association for Food Protection.)

Non-O157 Shiga toxin-producing Escherichia coli (STEC) serogroups such as O26, O45, O103, O111, O121 and O145 often cause illness to people in the United States and the conventional identification of these "Big-Six" are complex. The label-free hyperspectral microscope imaging (HMI) method, which provides spectral "fingerprints" information of bacterial cells, was employed to classify serogroups at the cellular level. In spectral analysis, principal component analysis (PCA) method and stacked auto-encoder (SAE) method were conducted to extract principal spectral features for classification task. Based on these features, multiple classifiers including linear discriminant analysis (LDA), support vector machine (SVM) and soft-max regression (SR) methods were evaluated. Different sizes of datasets were also tested in search for the suitable classification models. Among the results, SAE-based classification models performed better than PCA-based models, achieving classification accuracy of SAE-LDA (93.5%), SAE-SVM (94.9%) and SAE-SR (94.6%), respectively. In contrast, classification results of PCA-based methods such as PCA-LDA, PCA-SVM and PCA-SR were only 75.5%, 85.7% and 77.1%, respectively. The results also suggested the increasing number of training samples have positive effects on classification models. Taking advantage of increasing dataset, the SAE-SR classification model finally performed better than others with average accuracy of 94.9% in classifying STEC serogroups. Specifically, O103 serogroup was classified with the highest accuracy of 97.4%, followed by O111 (96.5%), O26 (95.3%), O121 (95%), O145 (92.9%) and O45 (92.4%), respectively. Thus, the HMI technology coupled with SAE-SR classification model has the potential for "Big-Six" identification., (Copyright © 2019. Published by Elsevier B.V.)

Foodborne bacteria are some of the most important human pathogens and can cause many diseases. In this study, multiplex PCR amplification combined with microchip electrophoresis (MCE) was studied to simultaneously and sensitively detect Staphylococcus aureus, Proteus mirabilis, and Enterobacter sakazakii. In order to simultaneously and accurately detect the aim bacteria, three pairs of primers were specially designed for the multiplex PCR amplification of the target genes of three bacteria, which were the specific genes corresponding to these bacteria respectively. After the DNA fragments of three bacteria were simultaneously extracted, the multiplex PCR amplification was performed by adding the three pairs of specific primers in the mixed DNA fragments solution. The multiplex PCR products of the three food-borne pathogens were analyzed by MCE and the limits of detection of target DNA fragments were 1.2-2.2ngμL -1 , (S/N=3). The limits of detection of the aim bacteria were calculated as 53CFUmL -1 for Enterobacter sakazakii, 32CFUmL -1 for Proteus mirabilis, 28CFUmL -1 for Staphylococcus aureus, respectively. Satisfactory results were obtained when this method was applied to detect the three foodborne bacteria in milk samples. The experimental results show that this method has the advantages of quickness, less sample consumption, high selectivity and high sensitivity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this work, modifications of cell membrane fluidity, fatty acid composition and fatty acid biosynthesis-associated genes of Escherichia coli ATCC 25922 (E. coli) and Staphylococcus aureus ATCC 6538 (S. aureus), during growth in the presence of naringenin (NAR), one of the natural antibacterial components in citrus plants, was investigated. Compared to E. coli, the growth of S. aureus was significantly inhibited by NAR in low concentrations. Combination of gas chromatography-mass spectrometry with fluorescence polarization analysis revealed that E. coli and S. aureus cells increased membrane fluidity by altering the composition of membrane fatty acids after exposure to NAR. For example, E. coli cells produced more unsaturated fatty acids (from 18.5% to 43.3%) at the expense of both cyclopropane and saturated fatty acids after growth in the concentrations of NAR from 0 to 2.20mM. For S. aureus grown with NAR at 0 to 1.47mM, the relative proportions of anteiso-branched chain fatty acids increased from 37.2% to 54.4%, whereas iso-branched and straight chain fatty acids decreased from 30.0% and 33.1% to 21.6% and 23.7%, respectively. Real time q-PCR analysis showed that NAR at higher concentrations induced a significant down-regulation of fatty acid biosynthesis-associated genes in the bacteria, with the exception of an increased expression of fabA gene. The minimum inhibitory concentration (MIC) of NAR against these two bacteria was determined, and both of bacteria underwent morphological changes after exposure to 1.0 and 2.0 MIC., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The objective of this study was to investigate the effect of 460 nm light-emitting diode (LED) on the inactivation of foodborne bacteria. Additionally, the change in the endogenous metabolic profile of LED illuminated cells was analyzed to understand the bacterial response to the LED illumination. Six different species of bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, Pseudomonas aeruginosa and Salmonella Typhimurium) were illuminated with 460 nm LED to a maximum dose of 4080 J/cm 2 at 4, 10 and 25 °C. Inactivation curves were modeled using Hom model. Metabolic profiling of the non-illuminated and illuminated cells was performed using a Liquid chromatography-mass spectrometry system. Results indicate that the 460 nm LED significantly (p < 0.05) reduced the populations of all six bacterial species. For example, the population of S. aureus reached below detection limit within 7 h. B. cereus was most resistant to photo-inactivation and exhibited about 3-log reduction in 9 h. Metabolic profiling of the illuminated cells indicated that several metabolites e.g. 11-deoxycortisol, actinonin, coformycin, tyramine, chitobiose etc. were regulated during LED illumination. These results elucidate the effectiveness of 460 nm LED against foodborne bacteria and hence, its suitability as a novel antimicrobial control method to ensure food safety., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Although antimicrobial activities of plant essential oils are well documented, challenges remain as to their application in fresh produce due to the hydrophobic nature of essential oils. Oregano oil nanoemulsions were formulated with a food-grade emulsifier and evaluated for their efficacy in inactivating the growth of foodborne bacteria on fresh lettuce. Lettuce was artificially inoculated with Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli O157:H7, followed by a one-minute dipping in oregano oil nanoemulsions (0.05% or 0.1%). Samples were stored at 4 °C and enumerated for bacteria at fixed intervals (0 h, 3 h, 24 h, and 72 h). Compared to control, 0.05% nanoemulsion showed an up to 3.44, 2.31, and 3.05 log CFU/g reductions in L. monocytogenes, S. Typhimurium, and E. coli O157:H7, respectively. Up to 3.57, 3.26, and 3.35 log CFU/g reductions were observed on the same bacteria by the 0.1% treatment. Scanning Electron Microscopy (SEM) demonstrated disrupted bacterial membranes due to the oregano oil treatment. The data suggest that applying oregano oil nanoemulsions to fresh produce may be an effective antimicrobial control strategy., (Copyright © 2014 Elsevier Ltd. All rights reserved.)