Journal of Food Safety最新文献

Food and water-borne enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is a zoonotic bacterium that causes gastroenteritis and other human diseases. It has also been linked to chronic foodborne diseases with high mortality rates worldwide, particularly in children. Hence, this study was carried out to designed a peptide base kit for quick detection of E. coli in food. A peptide-based rapid detection kit was designed using an immunoinformatic technique and some antigenic target genes (stx1A, stx2B, escC, fliC, and eae). The antigenic gene sequences retrieved were screened for antigenicity, transmembrane topology, B-cells and helper T-cells. Selected epitopes were joined with appropriate linkers to form a chimeric protein which consists of five B-cell epitopes, five interleukin-4 (IL-4) inducer epitopes and five interleukin-10 (IL-10) inducer epitopes. The improved and optimized chimeric protein sequence was cloned in-silico in a suitable expression host, E. coli-strain K12. The designed peptide refined and validated tertiary structure was molecularly docked with the tertiary structures of each antigenic target gene. The physicochemical properties of the chimeric protein showed that the construct has an amino acid length of 295 amino acids, a molecular weight of 29.876 kiloDalton (kDa), an aliphatic index of 75.05 and an instability index of 14.82 which confers stability. The construct was hydrophilic with a GRAVY value of −0.261 and had a considerable half-life of 4.4 h (mammalian reticulocytes, in vitro), >20 h (yeast, in vivo) and >10 h (E. coli, in vivo). Conclusively, the final construct has successfully met the design requirements for the development of a lateral flow kit, which has the potential to provide fast and efficient detection of E. coli O157:H7. However, it is the additional validation through the vitro and in vivo techniques needed to confirm that this designed peptide based test kit.

Salmonella enteric serovar Typhimurium is one of the causative agents for non-typhoidal salmonellosis which is highly associated with the consumption animal products such as eggs, pork, and poultry. Phytochemicals present in plant extracts were reported to improve food safety by inhibiting the growth of foodborne pathogens. Herein, the antimicrobial activities of Citrus limon and Bambusa polymorpha extracts were evaluated for their effectiveness in reducing the log counts of strains of S. Typhimurium inoculated in ground pork. The incorporation of undiluted extracts has resulted in 3.95 and 1.88 log reduction of S. Typhimurium, respectively with 2 h of exposure. Phytochemicals in the extracts that interfere with the activity of outer membrane (OmpA) and efflux pump regulatory proteins (MdfA, RamA) were also identified and interactions were anticipated using molecular docking and molecular dynamics simulation (MDS) studies. This study has revealed that the major phytochemicals present in the extracts were viz. phenol-2-ethyl, paracresol, 2, 3-dimethoxybenzoic acid, cyclobarbital, 3-methylsalicylhydrazide, and 3-methoxy-5-methylphenol. In order to evaluate the drug likeness and toxicity, phytochemicals were screened for their physiochemical and absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. ADMET studies has revealed that the screened phytochemicals with high docking scores had potent anti-bacterial abilities and could be used in drug design studies to develop natural plant products to preferentially target the outer membrane and efflux pump regulatory proteins of S. Typhimurium, which are critically important for the survival of S. Typhimurium under stress condition.

The food industry has inappropriate techniques for process and quality control and requires techniques that can provide information on the physical and chemical properties of food quickly and affordably. Food applications mostly focus on the identification of contaminants, with a few significant analytes, such as sugars, alcohols, amino acids, flavors, and sweeteners, as exceptions. Biosensors can bring about an analytical revolution to address the problems facing the food and agriculture industries. Potential applications for biosensors include contaminant detection, product freshness monitoring, content verification, and raw material conversion monitoring. These studies are costly and time-consuming due to the extraction or pre-treatment of samples. This review gives an overview of biosensors with their classification and application in different food industries such as the fruits and vegetable industry, dairy, and meat industries. The application of biosensors in detection, quality assurance, and food safety is discussed in detail with their potential application.

Here, the bactericidal efficacy and mechanism of action of the combination of alkaline electrolyzed water (AlEW) and acidic electrolyzed water (AcEW) on Pseudomonas aeruginosa biofilm were investigated, in comparison with single AcEW or AlEW treatment. The mature P. aeruginosa biofilm was formed at 120 h of cultivation. The number of bacteria in the P. aeruginosa biofilm decreased by 7.87 and 2.51 Lg CFU/mL after single AcEW and single AlEW treatment for 8 min, while the sterilization rate reached 92.2% and 33.1%, respectively. The group of AcEW (7 min) co-action with AlEW (1 min) had a P. aeruginosa sterilization rate of 85%. The AlEW (3 min) co-action with AcEW (5 min) treatment showed the best bactericidal efficacy. With this treatment, the sterilization rate achieved 94.4%, and the extracellular protein, polysaccharide, and DNA were degraded with the ratios of 70.8%, 77.7%, and 70.5%, respectively. Thus, AlEW exhibited a major washing effect, which can destroy the biofilm structure of extracellular polymers to a certain extent, while AcEW displayed a significant bactericidal effect. These results suggest that the AlEW co-action with AcEW treatment may be a promising candidate suitable for bacterial biofilm sterilization.

Human health is the biggest issue with consumption of contaminated vegetables and water. This study aimed to quantify heavy metals in soil, irrigation water, and vegetables in five urban and peri-urban area of Delhi. Under this study, vegetable crops, i.e. spinach, tomato, carrot, potato, onion and mustard were selected and soil, water and vegetable samples were analyzed for five toxic heavy metals, i.e. As, Cd, Cr, Hg, and Pb. Result showed that in irrigation water samples, Cd crossed the WHO/FAO permissible limit at Mehrauli and Najafgarh, while in all vegetable samples Cd content was detected more than permissible limit except for spinach. At all the sites, transfer factor and hazard risk index were observed higher in spinach and okra. The target hazard quotient were higher in spinach (1.184) and correlated with higher As content. Findings revealed that contaminated vegetables consumption needs to be continuously monitored to avoid adverse health impacts.

Goat milk and protein hydrolysate peptides have generated significant interest due to their diverse range of biological functions. To produce these peptides, casein (CP), and whey proteins (WP) were partially purified from goat milk and subsequently hydrolyzed with gastrointestinal endopeptidases such as pepsin, trypsin, and α-chymotrypsin based on in silico selection to achieve gastrointestinal stable peptides. The hydrolysates were characterized using various techniques, including zeta sizer, polydispersity index (PDI), zeta potential, and reverse-phase high-performance liquid chromatography (RP-HPLC). The resulting peptides were then purified using RP-HPLC. To assess cytotoxicity, an MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide) assay was performed with fluorescence microscopy. Finally, cytokine levels were determined using enzyme-linked immunosorbent assay (ELISA). In comparison to WP and CP, the casein protein hydrolysates (CPH) and whey protein hydrolysates (WPH) peptides average particle size and PDI were decreased. The zeta potential of casein and whey peptides hydrolysates there were no differences. The RP-HPLC analysis revealed the production of peptides through the hydrolysis of CP and WP. These hydrolysates peptides were found to possess diverse biological activities, as evidenced by their significant inhibition of α-amylase, pancreatic lipase (PL), and angiotensin-converting enzyme (ACE), as well as their antibacterial properties against selected pathogens. Further investigations were carried out to understand the mode of action of these peptides using fluorescence and scanning electron microscope (SEM) microscopy. This study provides the first evidence of gastrointestinal stable peptides derived from goat milk with inhibitory activity against α-amylase, PL, and ACE, as well as antibacterial properties against specific pathogens. Additionally, the peptides demonstrated significant cytokine inhibition and low toxicity toward the HT-29 cell line. This study strongly suggests that the biologically active peptides responsible for the health-related bioactive properties described here, which are considered functional and nutraceutical ingredients, should be identified and validated in subsequent research, particularly the most effective hydrolysate peptides derived from goat milk protein. Goat milk is widely recognized as an excellent source of milk protein. In this study, bioactive peptides were produced using casein and whey proteins from goat milk, which exhibited inhibitory activity against angiotensin converting enzyme, α-amylase, and pancreatic lipase, as well as antibacterial properties. Goat milk protein is a promising source for developing high-quality protein products with excellent safety standards that have potential applications in the pharmaceutical and food industries.

Climate change and its worldwide effects are undeniable. Temperature increase due to climate change may affect foodborne pathogen survival on fresh produce. This study aimed to present an evaluation of climate change impact regarding temperature rise situations, on attachment of different pathogenic Escherichia coli strains on cress grown under controlled conditions. EHEC O157:H7, EAEC O104:H4 and EPEC O26 were inoculated with initial inoculum concentration of 8 log MPN/mL at different stages during growth to observe how inoculation time (7, 14, 21 and 28 days post sowing; dps) and route (seed and leaves) affect pathogen load on fresh produce. This study revealed that temperature increase designed according to mitigation scenarios for climate change (+2, +4 and +6 °C) did not cause any considerable change in pathogen persistence on leaf at 30 dps (~4.5 to 7 log MPN/g). In plants contaminated at later stage (21 and 28 dps), higher bacterial populations were obtained for all temperatures studied. Our results show that E. coli translocated towards leaf portions from seed and established significant amount of pathogen load on leaf (~4 to 5.3 log MPN/g). Also, inoculated bacteria have tightly bound to leaf (~3.5 to 7 log MPN/g) and cannot be eliminated by washing. Although persistence of E. coli O157:H7, O104:H4 and O26 did not differ significantly according to temperature, the bacterial load on the leaves was above infectious dose for humans.

As the interest in “natural” and “safe” products grows, the use of natural products instead of synthetic preservatives to combat food spoilage and poisoning caused by microorganisms during processing and storage has become a prioritized option. The present research evaluated the antibacterial activity of the Mentha longifolia L. essential oil (MLEO) against several pathogenic bacteria, and the mechanism of action against methicillin-resistant Staphylococcus aureus (MRSA). Gas Chromatography Quadrupole Time-of-Flight Mass Spectrometry (GC-Q-TOF MS) analysis suggested that main components of MLEO were carvone (47.39%) and limonene (12.48%). The oil showed considerable antibacterial activity with MIC values of 0.394–1.576 mg/mL, and could be a promising bactericide. Non-targeted metabolomics analysis based on GC-Q-TOF MS identified 66 different metabolites, and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of these metabolites revealed that MLEO achieves the effects by affecting amino acid metabolism in MRSA.

Tan, J. N., Hwang, C.-A., Huang, L., Wu, V. C. H., & Hsiao, H.-I. (2023). A pilot-scale evaluation of using gaseous chlorine dioxide for decontamination of foodborne pathogens on produce and low-moisture foods. Journal of Food Safety, 43(2), e12937. https://doi.org/10.1111/jfs.12937

In the Abstract, the number “9” from the sentence “…ClO_2(g) concentrations (mg/L) and times 9 (hr) at 70–95% RH…” should be deleted. The sentence should read “…ClO_2(g) concentrations (mg/L) and times (hr) at 70–95% RH…”

We apologize for this error.

The addition of probiotic bacteria creates added value to food products wrapped with edible film. Hence, this study aimed to develop sodium caseinate (NaCas) edible film containing Bifidobacterium breve. The edible film was prepared by using different NaCas concentrations (2%–6% wt/vol), glycerol, and B. breve suspension (1% vol/vol). The edible film without probiotics was used as a control film. The optimized 3% (wt/vol) NaCas-B. breve edible film had a viable cell count of 7.07 log₁₀ CFU/g, thickness of 0.16 mm, 63.50% water solubility, 14.04% moisture content, the color difference (ΔE) <2.59, 3.31 mPa tensile strength, 35.73% elongation at break, and 0.10 mPa Young's modulus. Furthermore, the NaCas-B. breve edible film had also shown inhibition against Escherichia coli, Klebsiella pneumoniae, and Salmonella enterica. The desirable physicochemical properties, high viability, and antibacterial properties of 3% (wt/vol) NaCas-B. breve edible films may enable their future use as bioactive packaging for food products.