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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]

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]

Background: Salmonella, an important foodborne pathogen, was estimated to be responsible for 95.1 million cases and 50,771 deaths worldwide. Sixteen serovars were responsible for approximately 80% of Salmonella infections in humans in China, and infections caused by a few uncommon serovars have been reported in recent years, though not with S. Welikade. This study reports the first clinical case caused by S. Welikade in China and places Chinese S. Welikade isolates in the context of global isolates via genomic analysis. For comparison, S. Welikade isolates were also screened in the Chinese Local Surveillance System for Salmonella (CLSSS). The minimum inhibitory concentrations (MICs) of 28 antimicrobial agents were determined using the broth microdilution method. The isolates were sequenced on an Illumina platform to identify antimicrobial resistance genes, virulence genes, and phylogenetic relationships. Results: The S. Welikade isolate (Sal097) was isolated from a two-year-old boy with acute gastroenteritis in 2021. Along with the other two isolates found in CLSSS, the three Chinese isolates were susceptible to all the examined antimicrobial agents, and their sequence types (STs) were ST5123 (n = 2) and ST3774 (n = 1). Single nucleotide polymorphism (SNP)-based phylogenetic analysis revealed that global S. Welikade strains can be divided into four groups, and these three Chinese isolates were assigned to B (n = 2; Sal097 and XXB1016) and C (n = 1; XXB700). In Group B, the two Chinese ST5123 isolates were closely clustered with three UK ST5123 isolates. In Group C, the Chinese isolate was closely related to the other 12 ST3774 isolates. The number of virulence genes in the S. Welikade isolates ranged from 59 to 152. The galF gene was only present in Group A, the pipB2 gene was only absent from Group A, the avrA gene was only absent from Group B, and the allB, sseK1, sspH2, STM0287, and tlde1 were found only within Group C and D isolates. There were 15 loci unique to the Sal097 isolate. Conclusion: This study is the first to characterize and investigate clinical S. Welikade isolates in China. Responsible for a pediatric case of gastroenteritis in 2021, the clinical isolate harbored no antimicrobial resistance and belonged to phylogenetic Group B of global S. Welikade genomes. [ABSTRACT FROM AUTHOR]

Milk contaminated with trace amounts of foodborne pathogens can considerably threaten food safety and public health. Therefore, rapid and accurate detection techniques for foodborne pathogens in milk are essential. Nucleic acid amplification (NAA)-based strategies are widely used to detect foodborne pathogens in milk. This review article covers the mechanisms of the NAA-based detection of foodborne pathogens in milk, including polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), recombinase polymerase amplification (RPA), rolling circle amplification (RCA), and enzyme-free amplification, among others. Key factors affecting detection efficiency and the advantages and disadvantages of the above techniques are analyzed. Potential on-site detection tools based on NAA are outlined. We found that NAA-based strategies were effective in detecting foodborne pathogens in milk. Among them, PCR was the most reliable. LAMP showed high specificity, whereas RPA and RCA were most suitable for on-site and in-situ detection, respectively, and enzyme-free amplification was more economical. However, factors such as sample separation, nucleic acid target conversion, and signal transduction affected efficiency of NAA-based strategies. The lack of simple and effective sample separation methods to reduce the effect of milk matrices on detection efficiency was noteworthy. Further research should focus on simplifying, integrating, and miniaturizing microfluidic on-site detection platforms. [ABSTRACT FROM AUTHOR]

Foodborne pathogenic infection has brought multifaceted issues to human life, leading to an urgent demand for advanced detection technologies. CRISPR/Cas-based biosensors have the potential to address various challenges that exist in conventional assays such as insensitivity, long turnaround time and complex pretreatments. In this perspective, we review the relevant strategies of CRISPR/Cas-assisted diagnostics on foodborne pathogens, focusing on biosensing platforms for foodborne pathogens based on fluorescence, colorimetric, (electro)chemiluminescence, electrochemical, and surface-enhanced Raman scattering detection. It summarizes their detection principles by the clarification of foodborne pathogenic bacteria, fungi, and viruses. Finally, we discuss the current challenges or technical barriers of these methods against broad application, and put forward alternative solutions to improve CRISPR/Cas potential for food safety. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes, a prominent foodborne pathogen responsible for zoonotic infections, owes a significant portion of its virulence to the presence of the phospholipase PlcB. In this study, we performed an in-depth examination of the intricate relationship between L. monocytogenes PlcB and host cell mitochondria, unveiling a novel participant in bacterial survival: the mitochondrial carboxylase propionyl-coenzyme A carboxylase (PCCA). Our investigation uncovered previously unexplored levels of interaction and colocalization between PCCA and PlcB within host cells, with particular emphasis on the amino acids 504-508 of PCCA, which play a pivotal role in this partnership. To assess the effect of PCCA expression on L. monocytogenes proliferation, PCCA expression levels were manipulated by siRNA-si-PCCA or pCMV-N-HA-PCCA plasmid transfection. Our findings demonstrated a clear inverse correlation between PCCA expression levels and the proliferation of L. monocytogenes. Furthermore, the effect of L. monocytogenes infection on PCCA expression was investigated by assessing PCCA mRNA and protein expression in HeLa cells infected with L. monocytogenes. These results indicate that L. monocytogenes infection did not significantly alter PCCA expression. These findings led us to propose that PCCA represents a novel participant in L. monocytogenes survival, and its abundance has a detrimental impact on bacterial proliferation. This suggests that L. monocytogenes may employ PlcB-PCCA interactions to maintain stable PCCA expression, representing a unique pro-survival strategy distinct from that of other intracellular bacterial pathogens. [ABSTRACT FROM AUTHOR]

The foodborne pathogen Listeria monocytogenes is differentiated into four distinct lineages which differ in their virulence. It remains unknown, however, whether the four lineages also differ with respect to their ability to persist in food processing facilities, their resistance to high pressure, a preservation method that is used commercially for Listeria control on ready-to-eat meats, and their ability to form biofilms. This study aimed to determine differences in the pressure resistance and biofilm formation of 59 isolates of L. monocytogenes representing lineages I and II. Furthermore, the genetic similarity of 9 isolates of L. monocytogenes that were obtained from a meat processing facility over a period of 1 year and of 20 isolates of L. monocytogenes from food processing facilities was analyzed to assess whether the ability of the lineages of L. monocytogenes to persist in these facilities differs. Analysis of 386 genomes with respect to the source of isolation revealed that genomes of lineage II are over-represented in meat isolates when compared with clinical isolates. Of the 38 strains of Lm. monocytogenes that persisted in food processing facilities (this study or published studies), 31 were assigned to lineage II. Isolates of lineage I were more resistant to treatments at 400 to 600 MPa. The thickness of biofilms did not differ between lineages. In conclusion, strains of lineage II are more likely to persist in food processing facilities while strains of lineage I are more resistant to high pressure. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the antimicrobial effectiveness of cinnamaldehyde (CIN) and potassium sorbate (P.S.), alone and in combination, against Salmonella Typhimurium and Staphylococcus aureus in vitro and in apple jam. Antimicrobial activity in vitro was investigated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), time-kill assay and determination of fractional inhibitory concentration index. CIN MIC and MBC was 312 μg/mL. P.S. MIC and MBC were 2500 and 5000 μg/mL, respectively, against S. Typhimurium; and 10,000 and 20,000 μg/mL, respectively, against S. aureus. The compounds combined exhibited a synergistic effect (FIC < 0.5), inhibiting S. Typhimurium growth after 12 h and S. aureus after 24 h. The effect of CIN and P.S., at sub-inhibitory concentrations, against bacterial strains in apple jam was evaluated during storage. Physicochemical and sensory analyses were also performed. No cultivable S. Typhimurium or S. aureus cells were recovered in apple jam supplemented with CIN + P.S. on the third day of storage. The addition of CIN and P.S. did not affect the physicochemical properties and sensory evaluation showed a score above 7.0. CIN and P.S. association at sub-inhibitory concentrations was effective in controlling foodborne pathogens and improved the shelf life of apple jam. [ABSTRACT FROM AUTHOR]

Foodborne diseases can be attributed not only to contamination with bacterial or fungal pathogens but also their associated toxins. Thus, to maintain food safety, innovative decontamination techniques for toxins are required. We previously demonstrated that an atmospheric-pressure dielectric-barrier discharge (APDBD) plasma generated by a roller conveyer plasma device is effective at inactivating bacteria and fungi in foods. Here, we have further examined whether the roller conveyer plasma device can be used to degrade toxins produced by foodborne bacterial pathogens, including aflatoxin, Shiga toxins (Stx1 and Stx2), enterotoxin B and cereulide. Each toxin was spotted onto an aluminum plate, allowed to dry, and then treated with APDBD plasma applied by the roller conveyer plasma device for different time periods. Assessments were conducted using a competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography–tandem mass spectrometry (LC-MS/MS). The results demonstrate a significant time-dependent decrease in the levels of these toxins. ELISA showed that aflatoxin B1 concentrations were reduced from 308.6 µg/mL to 74.4 µg/mL within 1 min. For Shiga toxins, Stx1 decreased from 913.8 µg/mL to 65.1 µg/mL, and Stx2 from 2309.0 µg/mL to 187.6 µg/mL within the same time frame (1 min). Enterotoxin B levels dropped from 62.67 µg/mL to 1.74 µg/mL at 15 min, and 1.43 µg/mL at 30 min, but did not display a significant decrease within 5 min. LC-MS/MS analysis verified that cereulide was reduced to below the detection limit following 30 min of APDBD plasma treatment. Taken together, these findings highlight that a range of foodborne toxins can be degraded by a relatively short exposure to plasma generated by an APDBD using a roller conveyer device. This technology offers promising advancements in food safety, providing a novel method to alleviate toxin contamination in the food processing industry. [ABSTRACT FROM AUTHOR]

Microbial foodborne pathogens present significant challenges to public health and the food industry, requiring rapid and accurate detection methods to prevent infections and ensure food safety. Conventional single biosensing techniques often exhibit limitations in terms of sensitivity, specificity, and rapidity. In response, there has been a growing interest in multimodal biosensing approaches that combine multiple sensing techniques to enhance the efficacy, accuracy, and precision in detecting these pathogens. This review investigates the current state of multimodal biosensing technologies and their potential applications within the food industry. Various multimodal biosensing platforms, such as opto-electrochemical, optical nanomaterial, multiple nanomaterial-based systems, hybrid biosensing microfluidics, and microfabrication techniques are discussed. The review provides an in-depth analysis of the advantages, challenges, and future prospects of multimodal biosensing for foodborne pathogens, emphasizing its transformative potential for food safety and public health. This comprehensive analysis aims to contribute to the development of innovative strategies for combating foodborne infections and ensuring the reliability of the global food supply chain. [ABSTRACT FROM AUTHOR]

Foodborne diseases caused by bacterial contamination are a serious threat to food safety and human health. The classical plate culture method has the problems of long detection cycle, low sensitivity and specificity, and complicated operation, which cannot meet the growing demand for rapid quantitative detection of pathogenic bacteria. The frequent outbreak of foodborne diseases has put forward higher requirements for rapid and simple detection technology of foodborne pathogens. Aptamer is a kind of oligonucleotide fragment that can recognize targets with the advantages of high affinity and good specificity. The target can be range from proteins, small molecules, cells bacteria, and even viruses. Herein, the latest advances in sensitive and rapid detection of foodborne pathogens based on aptamer recognition was reviewed. Special attention has been paid to the obtained sequences of aptamers to various foodborne pathogens, the optimization of sequences, and the mechanism of aptamer recognition. Then, the research progress of biosensors for the detection of pathogenic bacteria based on aptamer recognition were summarized. Some challenges and prospects for the detection of foodborne pathogens based on aptamer recognition were prospected. In summary, with the further deepening of aptamer research and improvement of detection technology, aptamer-based recognition can meet the needs of rapid, sensitive, and accurate detection in practical applications. [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]

In this pilot study, we compared the metagenomic profiles of different types of artisanal fermented meat products collected in Italy, Greece, Portugal, and Morocco to investigate their taxonomic profile, also in relation to the presence of foodborne pathogens and antimicrobial resistance genes. In addition, technical replicates of the same biological sample were tested to estimate the reproducibility of shotgun metagenomics. The taxonomic analysis showed a high level of variability between different fermented meat products at both the phylum and genus levels. Staphylococcus aureus was identified with the highest abundance in Italian fermented meat; Escherichia coli in fermented meat from Morocco; Salmonella enterica in fermented meat from Greece; Klebsiella pneumoniae and Yersinia enterocolitica in fermented meat from Portugal. The fungi Aspergillus, Neosartoria, Emericella, Penicillum and Debaryomyces showed a negative correlation with Lactococcus, Enterococcus, Streptococcus, Leuconostoc and Lactobacillus. The resistome analysis indicated that genes conferring resistance to aminoglycoside, macrolide, and tetracycline were widely spread in all samples. Our results showed that the reproducibility between technical replicates tested by shotgun metagenomic was very high under the same conditions of analysis (either DNA extraction, library preparation, sequencing analysis, and bioinformatic analysis), considering both the degree of overlapping and the pairwise correlation. [ABSTRACT FROM AUTHOR]

Background and Aim: Klebsiella pneumoniae is one of the most common causes of clinical and asymptomatic mastitis in dairy cattle, as well as in milk and dairy products that affect milk quality. Mastitis caused by K. pneumoniae is even more serious due to its poor response to antibiotic therapy. The aim of this study was to detect and identify the presence of K. pneumoniae in milk and dairy products produced in Libya. Materials and Methods: A total of 234 samples were randomly collected from various locations in Libya. Samples were examined for the presence of K. pneumoniae using conventional cultural techniques, including cultivation in violet red bile agar plus 4-methylumbelliferyl-β-D-glucuronide broth and CHROM agar, followed by polymerase chain reaction identification and partial sequencing of 16S rRNA. Results: Of the 234 samples of milk and dairy products collected, 16 (6.8%) isolates revealed mucoid colonies on agar media that were phenotypically suggested to be K. pneumoniae. Identification of isolates was confirmed using molecular techniques (16S rRNA). Among the examined samples, K. pneumoniae was recovered from camel's milk, raw cow's milk, raw fermented milk, Maasora cheese, Ricotta cheese, soft cheese, full cream milk powder, milk powder infant formula, cereal baby food, and growing-up formula. Antibiotic susceptibility testing was performed on 12 of the 16 K. pneumoniae isolates, and the results showed that K. pneumoniae isolates were resistant to more than eight antibiotics; interestingly, two isolates showed metallo-beta-lactamase (MBL) production. Conclusion: K. pneumoniae is considered a risk to human health because many of these products do not comply with the microbiological criteria of international and/or Libyan standards. This study emphasized the relationship between K. pneumoniae and raw milk, cheese, milk powder, and infant milk retailed in Libya. There is a need to take the necessary measures to ensure effective hygiene practices during production in dairy factories, handling, and distribution on the market, in particular at a small local production scale. [ABSTRACT FROM AUTHOR]

Background For pathogen detection in food, there are occasions where samples cannot be processed immediately after selective enrichment or need to be reexamined days or weeks later for confirmation or retest. Objective This study aimed to investigate the effect of different prolonged period of storage of selective enrichments of food at 4 ± 2°C and room temperature (20–22°C) on the detection and isolation of Salmonella. Method This study included two experiments involving 34 types of foods to compare the effect of 4 ± 2°C and room temperature storage on the detection of Salmonella in 204 selective enrichments (Rappaport-Vassiliadis [RV] and Tetrathionate [TT] broths) during a 42-day storage (Experiment I); and to monitor the survival of Salmonella in 300 selective enrichments (RV and TT) with different pre-enrichment broths (Lactose broth [LB] or Buffered peptone water broth [BPW]), stored at 4°C for 60 days (Experiment II). All the samples were subjected to Salmonella analysis following the FDA BAM method. Results During multiple samplings, the positive detection rate for Salmonella remained consistent through Day 42 after selective enrichment, irrespective of Salmonella serotype, storage temperature, pre-enrichment broth, or selective enrichment broth in both Experiment I and II. However, on Day 60 sampling in Experiment II, seven previously positive results turned to negatives. These data indicated that storage of RV and TT enrichments at 4 ± 2°C or room temperature for up to 42 days after selective enrichment did not compromise the detection of Salmonella in the tested food categories, regardless of Salmonella serotypes and the broths used for pre-enrichment and selective enrichment. Conclusions At least for the food types studied in this experiment, the recovery of Salmonella from selective enrichments could be postponed for a limited period of time (e.g. <42 days) if needed without adversely affecting the test results. However, the delayed analysis of TT and RV enrichments does pose a risk of reduced detection sensitivity, as evidenced by the seven negative results on Day 60 compared to previous positives. We do not recommend or endorse delaying the analysis of TT and RV enrichments. Highlights In the food matrixes investigated in this experiment, the plating and isolation of Salmonella from selective TT and RV enrichments stored at 4 ± 2°C or room temperature could be deferred for a period (up to 42 days) without any negative effect on the test results, if necessary. [ABSTRACT FROM AUTHOR]

Background and aim: Different Salmonella serotypes are considered one of the most important food pathogens in the world. Poultry meat and eggs are the primary carriers of Salmonella in human populations. This study aimed to estimate the Salmonella enteritidis and Salmonella typhimurium contamination rates of retail hen and quail eggs in Karaj, Iran. Moreover, the antimicrobial resistance patterns of the strains were evaluated, and the efficiency of the standard culture method and multiplex polymerase chain reaction (m‐PCR) were compared. Materials and methods: In this descriptive cross‐sectional study over 1 year (Jan–Dec 2022), 150 commercial and 150 backyard hen eggs and 300 commercial quail eggs, without cracks and fractures, were collected randomly from best selling groceries in Karaj city. All samples were examined for Salmonella contamination independently by standard culture and m‐PCR approaches. A standard disc diffusion method was employed to assess the antimicrobial susceptibility of the strains against 18 antimicrobial agents. Results: Out of 300 examined eggs, 2 S. enteritidis strains were isolated from the shell of backyard hen eggs. The same serotype was also detected in the contents of one of these two eggs. One S. typhimurium was isolated from the shell of a commercial hen egg. Overall, the Salmonella contamination of the shell and contents was 1% and 0.3%, respectively. Salmonella was not isolated from the eggshells or the contents of the quail eggs. There was complete agreement between the results of m‐PCR and the standard culture methods. Among the 18 tested antibiotics, the highest resistance was recorded for colistin (100%), followed by nalidixic acid (75%). Conclusion: As most Salmonella spp. are associated with human food poisoning, continuous surveillance is required to effectively reduce the risk posed by contaminated poultry eggs. Furthermore, mandatory monitoring of antimicrobial use on Iranian poultry farms is recommended. [ABSTRACT FROM AUTHOR]

Symbiotic bacteria from seagrass and molluscs have the potential to be a source of secondary metabolites. Compounds from these secondary metabolites, such as natural food preservatives, can be used in the bioindustry sector. This research aims to identify the potential secondary metabolites from symbiotic bacteria in molluscs and seagrass that can support the Sustainable Development Goals (SDG) public health program. The samples used in this study were symbiotic bacteria of mollusc from seagrass environments, symbiotic bacteria from seagrass, and seagrass samples. The seagrass samples were analysed phytochemically, while the symbiotic bacteria samples from molluscs and seagrass were tested for their antibacterial activity against food spoilage pathogens such as Staphylococcus aureus and Escherichia coli using the disc diffusion method. Bacteria that showed potential antibacterial activity were identified using molecular methods, and the content of active compounds was analysed using gas chromatography-mass spectrometry. The phytochemical analysis revealed that seagrass contains flavones, tannins, steroids, and compounds with potential antibacterial properties. GC-MS analysis indicated that seagrass is predominantly composed of unsaturated fatty acids, which have antimicrobial effects by damaging bacterial cell membranes and disrupting the function of enzymes essential for growth and reproduction. Ten symbiotic bacteria isolates demonstrated proteolytic, cellulolytic, and lipolytic enzyme activity, suggesting their potential as antibacterial agents due to their ability to break down cell walls. Molecular identification of selected bacteria revealed the presence of mollusc symbionts, including Vibrio owensii, Bacillus paramycoides, and Pseudoalteromonas flavipulchra. The symbiotic bacteria found in seagrass in this study included Bacillus velezensis, Bacillus paramycoides, Nocardiopsis alba, Nocardiopsis alba, Bacillus tropicus, Lysinibacillus fusiformis, and Bacillus tropicus. GC-MS analysis of selected symbiotic bacteria from seagrass showed that the dominant compound components were phthalic acid, bis(7-methyl octyl) ester (25.18, 43.84, 35.55 %), and trimethoxy-3-piperidyl-2,2'-binaphthalene-1,1',4,4'-tetrone (36.36, 47.71, 64.48 %). In conclusion, seagrass and its symbiotic bacteria, as well as symbiotic bacteria from molluscs living in seagrass, have the potential to serve as antibacterial agents and can be used as references for food preservatives. [ABSTRACT FROM AUTHOR]

Bioactive peptides (BAPs) obtained from plants and microbes have been thoroughly explored and studied due to their prophylactic properties. The use of BAPs seems to be a promising substitute for several currently available antibiotics because of their antimicrobial properties against foodborne pathogens. BAPs have several other useful properties including antitumor, antihypertensive, antioxidant, antiobesity, and antidiabetic activities. Nowadays, scientists have attempted to recombinantly synthesize bioactive peptides to study their characteristics and potential uses, since BAPs are not found in large quantities in nature. Many pathogenic microorganisms including foodborne pathogens are becoming resistant to various antibiotics. To combat these pathogens, scientists are working to find novel, innovative, and safe antimicrobial agents. Plant- and microbe-based BAPs have demonstrated noteworthy antimicrobial activity against a wide range of pathogenic microorganisms, including foodborne pathogens. BAPs can kill pathogenic microorganisms by disrupting membrane integrity, inhibiting DNA and RNA synthesis, preventing protein synthesis, blocking protein activity, or interacting with certain intracellular targets. In addition, the positive effect of BAP consumption extends to gut microbiota modulation and affects the equilibrium of reactive oxygen species in the gut. This article discusses recombinant BAPs, BAPs generated from plants and microbes, and their antimicrobial applications and modes of action for controlling foodborne pathogens. [ABSTRACT FROM AUTHOR]

Background: Vibrio parahaemolyticus is the predominant etiological agent of seafood-associated foodborne illnesses on a global scale. It is essential to elucidate the mechanisms by which this pathogen disseminates. Given the existing research predominantly concentrates on localized outbreaks, there is a pressing necessity for a comprehensive investigation to capture strains of V. parahaemolyticus cross borders. Results: This study examined the frequency and genetic attributes of imported V. parahaemolyticus strains among travelers entering Shanghai Port, China, between 2017 and 2019.Through the collection of 21 strains from diverse countries and regions, Southeast Asia was pinpointed as a significant source for the emergence of V. parahaemolyticus. Phylogenetic analysis revealed clear delineation between strains originating from human and environmental sources, emphasizing that underlying genome data of foodborne pathogens is essential for environmental monitoring, food safety and early diagnosis of diseases. Furthermore, our study identified the presence of virulence genes (tdh and tlh) and approximately 120 antibiotic resistance-related genes in the majority of isolates, highlighting their crucial involvement in the pathogenesis of V. parahaemolyticus. Conclusions: This research enhanced our comprehension of the worldwide transmission of V. parahaemolyticus and its antimicrobial resistance patterns. The findings have important implications for public health interventions and antimicrobial stewardship strategies, underscoring the necessity for epidemiological surveillance of pathogen at international travel hubs. [ABSTRACT FROM AUTHOR]

Nowadays, metal oxide semiconductor gas sensors have diverse applications ranging from human health to smart agriculture with the development of Internet of Things (IoT) technologies. However, high operating temperatures and an unsatisfactory detection capability (high sensitivity, fast response/recovery speed, etc.) hinder their integration into the IoT. Herein, a ternary heterostructure was prepared by decorating WO3 nanoplates with Au and SnO2 nanoparticles through a facial photochemical deposition method. This was employed as a sensing material for 3-hydroxy-2-butanone (3H-2B), a biomarker of Listeria monocytogenes. These Au/SnO2–WO3 nanoplate-based sensors exhibited an excellent response (Ra/Rg = 662) to 25 ppm 3H-2B, which was 24 times higher than that of pure WO3 nanoplates at 140 °C. Moreover, the 3H-2B sensor showed an ultrafast response and recovery speed to 25 ppm 3H-2B as well as high selectivity. These excellent sensing performances could be attributed to the rich Au/SnO2–WO3 active interfaces and the excellent transport of carriers in nanoplates. Furthermore, a wireless portable gas sensor equipped with the Au/SnO2–WO3 nanoplates was assembled, which was tested using 3H-2B with known concentrations to study the possibilities of real-time gas monitoring in food quality and safety. [ABSTRACT FROM AUTHOR]

Foodborne pathogens are microbes present in food that cause serious illness when the contaminated food is consumed. Among these pathogens, Listeria monocytogenes is one of the most serious bacterial pathogens, and causes severe illness. The techniques currently used for L. monocytogenes detection are based on common molecular biology tools that are not easy to implement for field use in food production and distribution facilities. This work focuses on the efficacy of an electrochemical biosensor in detecting L. monocytogenes in chicken broth. The sensor is based on a nanostructured electrode modified with a bacteriophage as a bioreceptor which selectively detects L. monocytogenes using electrochemical impedance spectroscopy. The biosensing platform was able to reach a limit of detection of 55 CFU/mL in 1× PBS buffer and 10 CFU/mL in 1% diluted chicken broth. The biosensor demonstrated 83–98% recovery rates in buffer and 87–96% in chicken broth. [ABSTRACT FROM AUTHOR]

Heat stress can cause cell death by triggering the aggregation of essential proteins. In bacteria, aggregated proteins are rescued by the canonical Hsp70/AAA+ (ClpB) bi-chaperone disaggregase. Man-made, severe stress conditions applied during, e.g., food processing represent a novel threat for bacteria by exceeding the capacity of the Hsp70/ClpB system. Here, we report on the potent autonomous AAA+ disaggregase ClpL from Listeria monocytogenes that provides enhanced heat resistance to the food-borne pathogen enabling persistence in adverse environments. ClpL shows increased thermal stability and enhanced disaggregation power compared to Hsp70/ClpB, enabling it to withstand severe heat stress and to solubilize tight aggregates. ClpL binds to protein aggregates via aromatic residues present in its N-terminal domain (NTD) that adopts a partially folded and dynamic conformation. Target specificity is achieved by simultaneous interactions of multiple NTDs with the aggregate surface. ClpL shows remarkable structural plasticity by forming diverse higher assembly states through interacting ClpL rings. NTDs become largely sequestered upon ClpL ring interactions. Stabilizing ring assemblies by engineered disulfide bonds strongly reduces disaggregation activity, suggesting that they represent storage states. [ABSTRACT FROM AUTHOR]

The goal of this study was to characterize the bacterial diversity on different melon varieties grown in different regions of the US, and determine the influence that region, rind netting, and variety of melon has on the composition of the melon microbiome. Assessing the bacterial diversity of the microbiome on the melon rind can identify antagonistic and protagonistic bacteria for foodborne pathogens and spoilage organisms to improve melon safety, prolong shelf-life, and/or improve overall plant health. Bacterial community composition of melons (n = 603) grown in seven locations over a four-year period were used for 16S rRNA gene amplicon sequencing and analysis to identify bacterial diversity and constituents. Statistically significant differences in alpha diversity based on the rind netting and growing region (p < 0.01) were found among the melon samples. Principal Coordinate Analysis based on the Bray-Curtis dissimilarity distance matrix found that the melon bacterial communities clustered more by region rather than melon variety (R2 value: 0.09 & R2 value: 0.02 respectively). Taxonomic profiling among the growing regions found Enterobacteriaceae, Bacillaceae, Microbacteriaceae, and Pseudomonadaceae present on the different melon rinds at an abundance of ≥ 0.1%, but no specific core microbiome was found for netted melons. However, a core of Pseudomonadaceae, Bacillaceae, and Exiguobacteraceae were found for non-netted melons. The results of this study indicate that bacterial diversity is driven more by the region that the melons were grown in compared to rind netting or melon type. Establishing the foundation for regional differences could improve melon safety, shelf-life, and quality as well as the consumers' health. [ABSTRACT FROM AUTHOR]

The plant produced powerful secondary metabolites and showed strong antibacterial activities against food-spoiling bacterial pathogens. The present study aimed to evaluate antibacterial activities and to identify metabolites from the leaves and stems of Catharanthus roseus using NMR spectroscopy. The major metabolites likely to be observed in aqueous extraction were 2,3-butanediol, quinic acids, vindoline, chlorogenic acids, vindolinine, secologanin, and quercetin in the leaf and stem of the Catharanthus roseus. The aqueous extracts from the leaves and stems of this plant have been observed to be most effective against food spoilage bacterial strains, followed by methanol and hexane. However, leaf extract was observed to be most significant in terms of the content and potency of metabolites. The minimum inhibitory concentration (20 µg/mL) and bactericidal concentrations (35 g/mL) of leaf extract were observed to be significant as compared to the ampicillin. Molecular docking showed that chlorogenic acid and vindolinine strongly interacted with the bacterial penicillin-binding protein. The docking energies of chlorogenic acid and vindolinine also indicated that these could be used as food preservatives. Therefore, the observed metabolite could be utilized as a potent antibacterial compound for food preservation or to treat their illness, and further research is needed to perform. [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]

Salmonellosis is one of the most common foodborne diseases worldwide. Surface adherence and biofilm formation are among the main strategies evolved by Salmonella to survive under harsh conditions and are risk factors for its spread through the food chain. Owing to the increase in antimicrobial resistance, there is a growing need to develop other methods to control foodborne pathogens, and bacteriophages have been suggested as a potential alternative for this purpose. The aim of this study was to evaluate bacteriophages as a biological control of Salmonella enterica serotypes to inhibit and remove bacterial biofilms. A total of 12 S. enterica isolates were selected for this study, all of which were biofilm producers. Seven bacteriophages were tested, individually and in a cocktail, for their host range and efficiency of plating (EOP). The phage cocktail was evaluated for its antibiofilm effect against the Salmonella biofilms. Phages UPF_BP1, UPF_BP2, UPF_BP3, UPF_BP6, and 10:2 possessed a broad lytic spectrum and could infect all S. enterica strains. Phages 10:2, UPF_BP6, and UPF_BP3 had high EOP in 10, 9, and 9 out of the 12 S. enterica strains, respectively. The cocktail was able to infect all S. enterica strains and had a high EOP in 10 out of 12 S. enterica isolates, presenting a broader host range than any of the tested single phages. A wide variation of inhibition among strains was observed, ranging from 14.72% to 88.53%. Multidrug-resistant and strong biofilm producer strains showed high biofilm inhibition levels by phage cocktail. Our findings demonstrate the ability of the cocktail to prevent biofilm formation and remove formed biofilms of Salmonella. These results indicate that the phage cocktail is a promising candidate to be used as an alternative for the control of Salmonella biofilms through surface conditioning. [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]

The purpose of this study was to identify the effect of amalgam UV lamp-activated gallic acid on the inactivation of foodborne pathogens (Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes). When the bactericidal effect of amalgam UV lamp-activated gallic acid was compared with that of conventional low-pressure (LP) Hg UV lamp-activated gallic acid, the reduction levels of all three foodborne pathogens were significantly higher by amalgam UV lamp-activated gallic acid than LP lamp-activated gallic acid. Bactericidal mechanism was investigated using four reactive oxygen species (ROS) scavengers (mannitol, sodium pyruvate, trion, and sodium azide) and a wider range of ROS was produced by amalgam lamp-activated gallic acid than LP lamp-activated gallic acid. It is assumed that dual-wavelength (185 and 254 nm) emission characteristics of amalgam lamp generate a wider range of ROS. When applied to cherry tomato samples, amalgam lamp-activated gallic acid reduced levels of pathogens to a significantly greater level than LP lamp-activated gallic acid. These results indicate that amalgam lamp-activated gallic acid can effectively control foodborne pathogens in the food processing industry. [ABSTRACT FROM AUTHOR]

In the case of a food poisoning outbreak, it is essential to understand the relationship between cooking workers and food poisoning. Many biological diagnostic methods have recently been developed to detect food poisoning pathogens. Among these diagnostic tools, this study presents PCR-based pulsed-field gel electrophoresis and nucleotide sequencing diagnostic analysis results for diagnosing food poisoning outbreaks associated with cooking employees in Chungcheongnam-do, Republic of Korea. Pulsed-field gel electrophoresis was useful in identifying the food poisoning outbreaks caused by Staphylococcus aureus and Enteropathogenic Escherichia coli. In the case of Norovirus, nucleotide sequencing was used to identify the relationship between cooking workers and the food poisoning outbreak. However, it is difficult to determine whether cooking employees directly caused the food poisoning outbreaks based on these molecular biological diagnostic results alone. A system is needed to integrate epidemiological and diagnostic information to identify a direct correlation between the food poisoning outbreak and cooking employees. [ABSTRACT FROM AUTHOR]

Summary: The aim of this work was to evaluate the prevalence of Listeria monocytogenes and other Listeria spp. in chicken, duck, quail, turkey and pork meat, including the antibiotic resistance of isolated strains. A total of 184 meat samples were collected from different retailers in La Rioja (Spain). The presence of Listeria spp. and L. monocytogenes were detected in 24.46% and 10.32% of the meat samples respectively. L. monocytogenes was the predominant Listeria spp. found in chicken, quail and pork meat, while L. innocua and L. welshimeri were the predominant species in duck and turkey meat respectively. A total of thirty‐three strains (55.93%) of Listeria spp. were found to be multi‐resistant (resistant to ≥3 families of antibiotics). The highest multi‐resistant rates were observed in L. monocytogenes (73.68%) and L. innocua (70.59%), followed by L. ivanovii (50%). Resistance to ampicillin and trimethoprim–sulfamethoxazole were found in L. monocytogenes strains isolated from chicken, being of special concern, since these antibiotics are used in the treatment of listeriosis. Special measures should be taken to reduce meat contamination such as adequate handling, correct preparation (cooking) and cleaning and disinfection in order to avoid cross‐contamination. [ABSTRACT FROM AUTHOR]

Summary: Staphylococcus aureus is a prominent foodborne pathogen causing Staphylococcal food poisoning (SFP) in dairy products. This study estimated S. aureus growth and thermal inactivation kinetic parameters and variability in various dairy products by conducting a meta‐analysis. Cheese exhibited a lower theoretical minimum temperature (Tmin), indicating favourable conditions for S. aureus growth even at lower temperatures. Tmin values for other matrices ranged from 5.0 to 7.2 °C, providing insights for production parameter formulation. Meanwhile, significant variations in the maximum population density (Ymax) are among dairy products at the same temperature. Keeping temperatures below 0 °C in pasteurised milk, raw milk and cheese limited Ymax to approximately 102–4 CFU mL−1, below the international toxicity threshold. Factors influencing D values were smaller than strain variability, and NaCl concentration emerged as a significant factor affecting S. aureus growth. These parameters can serve as references for quality control, safety and production optimisation in dairy product processes. [ABSTRACT FROM AUTHOR]

Controlling foodborne pathogens is challenging due to the new emergence of antimicrobial resistance to conventional antimicrobials. Therefore, new alternative antimicrobials need to be developed to control foodborne pathogens and avoid microbial resistance. Furthermore, the potential of trans-Himalayan high-altitude seabuckthorn (Hippophae rhamnoides ) plants has not been explored much for the synthesis of silver nanoparticles having antibacterial properties. Hence, this study investigated the development of long-term stable silver nanomaterials using the aqueous extract of seabuckthorn leaves through a green-synthesis approach and evaluated their antibacterial efficacy. These synthesized nanomaterials were characterized along with their stability using UV spectrometry for lambda max (λ max) characteristics. Further, the nanoparticles were evaluated for zeta potential (mV), polydispersity index, particle size distribution (nm), electrophoretic mobility (μ mcm/Vs) and conductivity (mS/cm). The seabuckthorn silver nanoparticles are of 260 nm size and stable (−15 mV zeta potential) with good antioxidant and antibacterial properties against two typical food pathogens, e.g., Escherichia coli (MTCC 3222) and Salmonella typhimurium (MTCC 3224). Hence, this study developed an eco-friendly, rapid, low-cost green synthesis method for the development of seabuckthorn-coated, stable silver nanoparticles with good antibacterial activity against foodborne pathogens. This study highlights the potential of trans-Himalayan high-altitude seabuckthorn (Hippophae rhamnoides) plants in the green synthesis of silver nanoparticles. It is a quick and cost-effective method with long-term stability, and the nanoparticles exhibit high antibacterial and antioxidant properties. [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]

The extensive use of synthetic antibiotics and insecticides in controlling microbes and insect spreads led to a build-up of resistance strains and caused negative impacts on human health through bioaccumulation in food and the environment. The present study assessed the antimicrobial activity of Amphora coffeaeformis (A. coffeaeformis) ethanolic extract against foodborne pathogenic microbes as well as assessed its ability to control Culex pipiens L. (C. pipiens) larvae. The gas chromatography-mass spectrum (GC/MS) and high-performance liquid chromatography (HPLC) analysis showed that A. coffeaeformis extract was rich with phenolic compounds, organosulfur compounds, carboxylic acids, amino acids, organic quinoline, dipeptide and monosaccharide. The extract of A. coffeaeformis showed antibacterial capability against all tested bacteria, with minimal inhibition concentration (MIC) values ranging from 20.2 to 66.7 g/mL, as well as antifungal effects against all tested mycotoxigenic fungi, with MIC values ranging from 113.62, 68.95 and 49.37 µg/mL mg/mL. Furthermore, the extract showed high larvicidal activity against C. pipiens larvae at 24, 48, and 72 h, respectively. LC50 values decreased gradually with the treatment period. Likewise, the adult emergence and growth index were significantly negatively related to increasing extract concentrations. Moreover, the extract exhibited a noteworthy depletion in the reproductive potential and increased sterility index of C. pipiens females developed of treated larvae. Besides a reduction in egg hatching percent, increase pupal malformations, increase and adult abnormalities. C. pipiens biochemical markers; glutathione-S-transferase, carboxylesterase, acetylcholinesterase, a-esterase and cytochrome P-450 showed significant alteration after the extract exposure. Overall, these findings promise the application possibility of A. coffeaeformis extract as a biopreservator against foodborne pathogens and as bioinsecticides for mosquito control as well. [ABSTRACT FROM AUTHOR]

Background: Listeria monocytogenes is a foodborne pathogen, which can cause a severe illness, especially in people with a weakened immune system or comorbidities. The interactions between host and pathogens and between pathogens and tumor cells have been debated in recent years. However, it is still unclear how bacteria can interact with tumor cells, and if this interaction can affect tumor progression and therapy. Methods: In this study, we evaluated the involvement of L. monocytogenes in pre-neoplastic and colorectal cancer cell proliferation and tumorigenic potential. Results: Our findings showed that the interaction between heat-killed L. monocytogenes and pre-neoplastic or colorectal cancer cells led to a proliferative induction; furthermore, by using a three-dimensional cell culture model, the obtained data indicated that L. monocytogenes was able to increase the tumorigenic potential of both pre-neoplastic and colorectal cancer cells. The observed effects were then confirmed as L. monocytogenes-specific, using Listeria innocua as negative control. Lastly, data suggested the Insulin Growth Factor 1 Receptor (IGF1R) cascade as one of the possible mechanisms involved in the effects induced by L. monocytogenes in the human colorectal adenocarcinoma cell line. Conclusions: These findings, although preliminary, suggest that the presence of pathogenic bacterial cells in the tumor niches may directly induce, increase, and stimulate tumor progression. [ABSTRACT FROM AUTHOR]

Background: Listeria monocytogenes is a foodborne pathogen, which can cause a severe illness, especially in people with a weakened immune system or comorbidities. The interactions between host and pathogens and between pathogens and tumor cells have been debated in recent years. However, it is still unclear how bacteria can interact with tumor cells, and if this interaction can affect tumor progression and therapy. Methods: In this study, we evaluated the involvement of L. monocytogenes in pre-neoplastic and colorectal cancer cell proliferation and tumorigenic potential. Results: Our findings showed that the interaction between heat-killed L. monocytogenes and pre-neoplastic or colorectal cancer cells led to a proliferative induction; furthermore, by using a three-dimensional cell culture model, the obtained data indicated that L. monocytogenes was able to increase the tumorigenic potential of both pre-neoplastic and colorectal cancer cells. The observed effects were then confirmed as L. monocytogenes-specific, using Listeria innocua as negative control. Lastly, data suggested the Insulin Growth Factor 1 Receptor (IGF1R) cascade as one of the possible mechanisms involved in the effects induced by L. monocytogenes in the human colorectal adenocarcinoma cell line. Conclusions: These findings, although preliminary, suggest that the presence of pathogenic bacterial cells in the tumor niches may directly induce, increase, and stimulate tumor progression. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare Illumina and Oxford Nanopore Technology (ONT) sequencing data to quantify genetic variation to assess within-outbreak strain relatedness and characterise microevolutionary events in the accessory genomes of a cluster of 23 genetically and epidemiologically linked isolates related to an outbreak of Shiga toxin-producing Escherichia coli O157:H7 caused by the consumption of raw drinking milk. There were seven discrepant variants called between the two technologies, five were false-negative or false-positive variants in the Illumina data and two were false-negative calls in ONT data. After masking horizontally acquired sequences such as prophages, analysis of both short and long-read sequences revealed the 20 isolates linked to the outbreak in 2017 had a maximum SNP distance of one SNP between each other, and a maximum of five SNPs when including three additional strains identified in 2019. Analysis of the ONT data revealed a 47 kbp deletion event in a terminal compound prophage within one sample relative to the remaining samples, and a 0.65 Mbp large chromosomal rearrangement (inversion), within one sample relative to the remaining samples. Furthermore, we detected two bacteriophages encoding the highly pathogenic Shiga toxin (Stx) subtype, Stx2a. One was typical of Stx2a-phage in this sub-lineage (Ic), the other was atypical and inserted into a site usually occupied by Stx2c-encoding phage. Finally, we observed an increase in the size of the pO157 IncFIB plasmid (1.6 kbp) in isolates from 2019 compared to those from 2017, due to the duplication of insertion elements within the plasmids from the more recently isolated strains. The ability to characterize the accessory genome in this way is the first step to understanding the significance of these microevolutionary events and their impact on the genome plasticity and virulence between strains of this zoonotic, foodborne pathogen. [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]

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]

Summary: The so‐called emerging technologies have gained prominence in the field of food processing, compared to conventional heat treatments, due to technological, sensorial and microbiological safety benefits. Ultraviolet radiation (UV), more specifically UV‐C radiation, is inexpensive and has been one of the most studied technologies. This work seeks to summarise the application of UV‐C treatment, contextualising its efficiency in the inactivation of microorganisms in different food matrices and surfaces associated with food handling and allowing the visualisation of trends in the combination of UV‐C radiation with other technologies. Still, the technology is related to quantitative tools associated with food microbiology. Factors related to processing parameters, characteristics of the microbial population and food properties have a direct influence on the effectiveness of UV‐C technology. The UV‐C treatment parameters must be rigorously defined, considering the particularities of each food matrix, so that undesirable identity or sensory changes do not occur. The application of mathematical tools, such as predictive microbiology and quantitative microbial risk assessment, is fundamental in the planning and definition of processing parameters for UV‐C radiation technology. [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 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]

Background: Food safety is a critical factor in promoting public health and nutrition, especially in developing countries like India, which experience several foodborne disease outbreaks, often with multidrug-resistant pathogens. Therefore, implementing regular surveillance of enteric pathogens in the human-animal-environment interface is necessary to reduce the disease burden in the country. Objective: To establish a network of laboratories for the identification of major food and waterborne pathogens prevailing in the northeast region of India through integrated surveillance of animal, food, human, and environment and investigate the antimicrobial susceptibility pattern of the pathogens of public health significance. Methods: The Indian Council of Medical Research (ICMR) has identified FoodNet laboratories; based on their geographical location, inclination to undertake the study, preparedness, proficiency, and adherence to quality assurance procedures, through an 8-step process to systematically expand to cover the Northeastern Region (NER) with comprehensive diagnostic capacities for foodborne pathogens and diarrhea outbreak investigations. Network initiated in the NER given the unique food habits of the ethnic population. Findings: This surveillance network for foodborne enteric pathogens was established in Assam, Arunachal Pradesh, Tripura, and Sikkim, and expanded to other four states, i.e., Manipur, Mizoram, Meghalaya, and Nagaland, thereby covering the entire NER by including nine medical and three veterinary centers. All these centers are strengthened with periodic training, technical support, funding, capacity building, quality assurance, monitoring, centralized digital data management, and website development. Results: The ICMR-FoodNet will generate NER-specific data with close to real-time reporting of foodborne disease and outbreaks, and facilitate the updating of food safety management protocols, policy reforms, and public health outbreak response. During 2020-2023, 13,981 food samples were tested and the detection of enteric pathogens ranged from 3 to 4%. In clinical samples, the detection rate of the pathogens was high in the diarrheal stools (8.9%) when 3,107 samples were tested. Thirteen outbreaks were investigated during the study period. Conclusion: Foodborne diseases and outbreaks are a neglected subject. Given the frequent outbreaks leading to the deaths of children, it is crucial to generate robust data through well-established surveillance networks so that a strong food safety policy can be developed for better public health. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is becoming an important issue for global wellness due to the widespread applications of antibiotics and chemical sanitizers. Therefore, it is necessary to investigate alternate approache for combating bacterial infections. One strategy is utilizing cutting-edge materials, such as gold nanoparticles (AuNPs). This investigation used Pseudomonas aeruginosa metabolic extract (ME), as reducing and stabilizing agent, to bio-manufacture of AuNPs. The extract's active gradient was utilized to reduce Au ions and transform them into Auo while stabilizing the produced nanoparticles using extract ingredients. Three samples, designated as 0.2 AuNPs@ME, 0.4 AuNPs@ME, and 0.6 AuNPs@ME, of AuNPs have been prepared by combining different amounts of gold salt. Based on the research's results, the biogenic synthetic AuNPs had crystalline structures and an average particle sizes of 48, 70, and 84 nm, respectively. The biofabricated AuNPs' antibacterial activity was also evaluated against foodborne pathogens, and their capacity to prevent biofilm formation was measured. The results showed that, 0.4 AuNPs@ME could suppress biofilm formation and had a robust bactericidal impact against certain bacterial species. This result is significant since the production of biofilms is a typical persistence strategy used by bacteria, rendering them resistant to antimicrobial treatments and challenging to eradicate. This study's findings imply that biofabricated AuNPs have significant antibacterial properties against foodborne pathogens and can be used as an efficient antimicrobial agent in food safety and sanitation applications. A particularly intriguing feature of AuNPs is their capacity to prevent the development of biofilms, which could prove the difficulties caused by foodborne bacteria. [ABSTRACT FROM AUTHOR]

Vibrio parahaemolyticus is the primary foodborne pathogen known to cause gastrointestinal infections in humans. Nevertheless, the molecular mechanisms of V. parahaemolyticus pathogenicity are not fully understood. Prophages carry virulence and antibiotic resistance genes commonly found in Vibrio populations, and they facilitate the spread of virulence and the emergence of pathogenic Vibrio strains. In this study, we characterized three such genes, VpaChn25_0713, VpaChn25_0714, and VpaChn25_RS25055, within the largest prophage gene cluster in V. parahaemolyticus CHN25. The deletion mutants ΔVpaChn25_RS25055, ΔVpaChn25_0713, ΔVpaChn25_0714, and ΔVpaChn25_RS25055-0713-0714 were derived with homologous recombination, and the complementary mutants ΔVpaChn25_0713-com, ΔVpaChn25_0714-com, ΔVpaChn25_RS25055-com, ΔVpaChn25_RS25055-0713-0714-com were also constructed. In the absence of the VpaChn25_RS25055, VpaChn25_0713, VpaChn25_0714, and VpaChn25_RS25055-0713-0714 genes, the mutants showed significant reductions in low-temperature survivability and biofilm formation (p < 0.001). The ΔVpaChn25_0713, ΔVpaChn25_RS25055, and ΔVpaChn25_RS25055-0713-0714 mutants were also significantly defective in swimming motility (p < 0.001). In the Caco-2 model, the above four mutants attenuated the cytotoxic effects of V. parahaemolyticus CHN25 on human intestinal epithelial cells (p < 0.01), especially the ΔVpaChn25_RS25055 and ΔVpaChn25_RS25055-0713-0714 mutants. Transcriptomic analysis showed that 15, 14, 8, and 11 metabolic pathways were changed in the ΔVpaChn25_RS25055, ΔVpaChn25_0713, ΔVpaChn25_0714, and ΔVpaChn25_RS25055-0713-0714 mutants, respectively. We labeled the VpaChn25_RS25055 gene with superfolder green fluorescent protein (sfGFP) and found it localized at both poles of the bacteria cell. In addition, we analyzed the evolutionary origins of the above genes. In summary, the prophage genes VpaChn25_0713, VpaChn25_0714, and VpaChn25_RS25055 enhance V. parahaemolyticus CHN25's survival in the environment and host. Our work improves the comprehension of the synergy between prophage-associated genes and the evolutionary process of V. parahaemolyticus. [ABSTRACT FROM AUTHOR]

Aims To address the increasingly serious challenge of the transmission of foodbrone pathogens in the food chain. Methods and results In this study, we employed rational design strategies, including truncation, amino acid substitution, and heterozygosity, to generate seven engineered peptides with α-helical structure, cationic property, and amphipathic characteristics based on the original Abhisin template. Among them, as the hybird antimicrobial peptide (AMP), AM exhibits exceptional stability, minimal toxicity, as well as broad-spectrum and potent antimicrobial activity against foodborne pathogens. Besides, it was observed that the electrostatic incorporation demonstrates by AM results in its primary targeting and disruption of the cell wall and membrane of Escherichia coli O157: H7 (EHEC) and methicillin-resistant Staphylococcus aureus (MRSA), resulting in membrane perforation and enhanced permeability. Additionally, AM effectively counteracts the deleterious effects of lipopolysaccharide, eradicating biofilms and ultimately inducing the demise of both food spoilage and pathogenic microorganisms. Conclusions The findings highlight the significant potential of AM as a highly promising candidate for a novel food preservative and its great importance in the design and optimization of AMP-related agents. [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]

Campylobacter jejuni is the predominant bacterial cause of gastroenteritis, the main cause of foodborne deaths. Currently, Campylobacter is a common foodborne pathogen found in poultry; thus, there is a need for the development of novel intervention strategies. The aim of the study was to examine the effect of eugenol on C. jejuni load in an experimental chicken meat model. We observed that eugenol was effective in reducing C. jejuni load for 7 days of storage. Eugenol treatment at all concentrations (1.28, 5.12, and 10.24 mg mL−1) decreased Campylobacter load more significantly in the reference strain, and this decrease was dose‐dependent throughout the storage period. Compared to the control group, eugenol reduced the counts of chicken isolate and the reference strain of C. jejuni by approximately 1.5 and 4.5 log/CFU, respectively, after 7 days of storage. Eugenol is a promising agent for improving the safety of poultry. [ABSTRACT FROM AUTHOR]

Foodborne pathogens can cause gastrointestinal infections in consumers and in some cases can even lead to outbreaks. In the last decade, it has been observed that some zoonotic pathogenic bacteria can use plants as secondary hosts. Contamination with foodborne bacteria becomes relevant in foods that are regularly eaten raw, such as lettuce, cilantro, fenugreek, rocket leaves, basil, and so forth, and some fruits such as tomatoes, melons, and green peppers; because the elimination of these pathogenic bacteria is difficult to achieve with conventional sanitization processes. Contamination of produce can occur throughout the entire production chain. In farmlands, pathogenic bacteria can contaminate the seed, mainly when contaminated water is used for irrigation. Later, bacteria can reach other plant tissues such as the stems, leaves, and fruits. Another form of contamination is when the produce is in contact with feces from domestic, production, or wild animals. Additionally, poor handling practices during harvest, packaging, distribution, and sale can contaminate produce. Studies have shown that foodborne pathogens can adhere to produce, sometimes forming a biofilm, and can also be internalized into the plant or fruit, which protects them from sanitation processes. For this reason, in this text we address three biocontrol strategies such as bacteria, lytic bacteriophages, and some fungi, as an alternative approach for the control of both foodborne and plant pathogens. Additionally, the use of these biological agents can represent an advantage for the development of the plant, making them a good strategy to favor yield. [ABSTRACT FROM AUTHOR]