Antibacterial efficiency of apple vinegar marination on beef-borne Salmonella.

Background: Salmonella-related foodborne illnesses are a significant public health concern. Naturally, antibacterial food components have been shown to limit microbial growth proliferation with various degrees of efficacy. Aims: To examine the occurrence, microbial load, and effect of apple vinegar on Salmonella serovars in beef and beef products. Methods: 150 beef and beef products were collected between March and May 2022. Total viable count (TVC), Enterobacteriaceae count (ENT), isolation and identification of Salmonella, and their virulence factors detection by multiplex PCR were determined, and an experimental study of the effect of natural apple vinegar marination on Salmonella spp. Results: TVC was higher in meatballs (3.32 × 106 ± 1.07 × 106) while beef burgers (4.22 × 103 ± 0.71 × 103) had the highest ENT. Concerning the prevalence of Salmonella spp., meatball (46.7%) and beef burger (25.3%) samples were the highest contamination rate. The common serovars detected were Salmonella typhimurium (6%), Salmonella enteritidis (6%), and Salmonella infantis (4%). Based on the results of PCR, 12, 11, and 11 out of 18 samples of Salmonella isolates possess hila, stn, and invA genes. By immersing the inoculated steak meat in apple vinegar at different concentrations (50%, 70%, and 100%), the initial populations of the Salmonella strains after 12 hours were reduced to 0.38 × 102 ± 0.05 × 102 log CFU/ml; however, after 48 hours become the most reduction (0.31 × 102 ± 0.07 × 102 log CFU/ml) at a concentration of 100% apple vinegar. An enhancement in the sensory attributes was noted across all concentrations. Conclusion: The consumed beef and beef products are contaminated with pathogenic bacteria such as Salmonella spp. Marinades made using apple vinegar concentrations of 50%, 75%, and 100% effectively minimized the prevalence of artificially inoculated Salmonella and extended the shelf life of preserved refrigerated beef products to 48 hours.

Fillet Fish Fortified with Algal Extracts of Codium tomentosum and Actinotrichia fragilis, as a Potential Antibacterial and Antioxidant Food Supplement.

With respect to the potential natural resources in the marine environment, marine macroalgae or seaweeds are recognized to have health impacts. Two marine algae that are found in the Red Sea, Codium tomentosum (Green algae) and Actinotrichia fragilis (Red algae), were collected. Antibacterial and antioxidant activities of aqueous extracts of these algae were evaluated in vitro. Polyphenols from the extracts were determined using HPLC. Fillet fish was fortified with these algal extracts in an attempt to improve its nutritional value, and sensory evaluation was performed. The antibacterial effect of C. tomentosum extract was found to be superior to that of A. fragilis extract. Total phenolic contents of C. tomentosum and A. fragilis aqueous extract were 32.28 ± 1.63 mg/g and 19.96 ± 1.28 mg/g, respectively, while total flavonoid contents were 4.54 ± 1.48 mg/g and 3.86 ± 1.02 mg/g, respectively. Extract of C. tomentosum demonstrates the highest antioxidant activity, with an IC50 value of 75.32 ± 0.07 µg/mL. The IC50 of L-ascorbic acid as a positive control was 22.71 ± 0.03 µg/mL. The IC50 values for inhibiting proliferation on normal PBMC cells were 33.7 ± 1.02 µg/mL and 51.0 ± 1.14 µg/mL for C. tomentosum and A. fragilis, respectively. The results indicated that both algal aqueous extracts were safe, with low toxicity to normal cells. Interestingly, fillet fish fortified with C. tomentosum extract demonstrated the greatest overall acceptance score. These findings highlight the potential of these seaweed species for cultivation as a sustainable and safe source of therapeutic compounds for treating human and fish diseases, as well as effective food supplements and preservatives instead of chemical ones after performing in vivo assays.

Quality Assessment, Functional Potentials, and Safety Evaluation of Stored Egyptian Honey as an Environmental Pollution Bioindicator.

Egyptian honeys are distinguished by their variety, properties, and therapeutic applications. The aim of the present study was to evaluate the quality and the functional and safety characteristics of Egyptian honey as a sensitive environmental bioindicator collected from 9 different locations in Egypt that were exposed to various air pollution sources, either stationary, mobile, or area sources, and stored for 6 mo at ambient temperature (22 ± 2 °C) compared with Codex Alimentarius international standards. Physicochemical properties, sugar profile via high performance liquid chromatography, functional potentials (antioxidant and antimicrobial), and safety parameters (microbiological quality, aflatoxins, and heavy metal pollutants) were assessed. The results revealed that honey obtained from Shabshir Hessa, El Gharbia Governorate (GSH-1), showed the best quality with the highest monosaccharide and phenolic and flavonoid content (73.07%, 363.07, and 15.33 mg/g, respectively) and clear of biotic and abiotic contaminants, reflecting good hygienic, environmental conditions and apiarian practices. The other 8 honey samples reflected inferior quality in physicochemical parameters either of low monosaccharide content (40.46-50.25%), high hydroxymethylfurfural (HMF) values as in Borg El-Arab Industrial Zone, Alexandria Governorate (BAI-9), and Nubaria Desert Road, Alexandria Governorate (NDR-4; 50.83 and 48.25 mg/kg), or of high acidity as in Agricultural Road, El Gharbia Governorate (GAR-3), and NDR-4 (74.72 and 68.47 mEq/kg) attributable to contaminated locations (fermentations) or thermal treatment (HMF). Furthermore, safety assessment revealed that coliform counts exceeded 2.5 log10 cfu/g in 6 samples-Chemicals Company, Kafr El Zayyat Governorate (KZC-2); GAR-3; NDR-4; Mansoura Fertilizer Talkha Company, Daqahlia Governorate (MFT-5); Gharbaniyat Cement Company, Beheira Governorate; and BAI-9-and the highest counts of yeast and molds in Abees Ceramic Company, Alexandria Governorate (3.72 log10 cfu/g), which was reflected in its total aflatoxins (679.83 µg/kg). Samples MFT-5; GAR-3; Kafr El-Sheikh Petroleum Company, Kafr El-Sheikh Governorate; and KZC-2 exceeded the lead permissible limit (0.75, 0.61, 0.57, and 0.51 mg/kg, respectively) as a result of inferior hygienic quality and the negative effects of environmental pollutants. The results ring alarm bells about how we should take substantial steps toward stringent standards for quality control practices of honey production operations. Environ Toxicol Chem 2020;39:1894-1907. © 2020 SETAC.

Anti-Escherichia coli O157:H7 as Natural Preservative to Control and Prevent Food Contamination in Meat and Fish Products.

BACKGROUND AND OBJECTIVE: Shiga toxin-producing Escherichia coli O157:H7 is a troubled foodborne pathogen associated with contamination of meat, fish and poultry. The present work aimed to evaluate plant extracts as natural preservatives anti- Escherichia coli O157:H7 in meat and fish products. MATERIALS AND METHODS: Antibacterial activity and minimum inhibitory concentrations (MICs) of seven herbal plants, clove, marjoram, sage, pomegranate peel, turmeric, Cassia fistula and black pepper and their different 6 mixes were examined against Escherichia coli O157:H7. Phytochemical qualitative analysis, phenolic compounds (HPLC), total phenolic, total flavonoid contents and antioxidant activities of individual extracts and their 6 mixes were evaluated. Combination Mix 5 extract was applied on meat and fish-fillet, then its antimicrobial effect against E. coli O157:H7 and sensory evaluation were assessed. RESULTS: Five extracts exhibited good antibacterial activity against Escherichia coli O157:H7. The greatest inhibition zone was recorded by clove aqueous extract (25 mm). Mix 5 (clove, sage, pomegranate and Cassia fistula) showed the highest inhibition with MIC of 3.0 mg mL-1. This mix exhibited strong anti-bactericidal effect against E. coli O157:H7 in meat and fish-fillet products throughout 8 days of cold storage (4°C). The sensory evaluation revealed that Mix 5 was acceptable by panelists with concentration of 0.50% in beef burgers and 0.25% in fish-fillet. CONCLUSION: This study suggests that the use of herbal extracts provide antibacterial potentials against food pathogens in meat and fish products.

Commercial probiotic cell-free supernatants for inhibition of Clostridium perfringens poultry meat infection in Egypt.

Prevalence of C. perfringens in Egyptian poultry causes severe economic losses in poultry industry which evokes innovative solutions for enhanced future prospects. The objective of this study was to employ probiotic cell-free supernatants for inhibition of Clostridium perfringens in poultry meat to control its prevalence in the Egyptian market. Four probiotic strains, Lactobacillus rhamnosus EMCC 1105, Lactobacillus fermentum EMCC 1346, Pediococcus acidilactici EMCC 1690 and Lactobacillus delbrueckii subsp. lactis EMCC supernatants' anti-clostridial effect was assessed using agar disk diffusion assay, while antioxidant potentials and phenolic compounds were determined through colorimetric methods; DPPH, Folin-Ciocalteu and High Performance Liquid Chromatography (HPLC). Fifteen out of 50 chicken samples collected from Alexandria Governorate, Egypt, with percent of 30%, showed positive results for presence of C. perfringens with counts reached 3.71 ±â€¯0.25 Log10 CFU/g. L. rhamnosus EMCC 1105 showed higher anti-clostridial potentials with inhibition zone diameter of 30  mm at concentration of 100 mg/ml and Minimum Inhibitory Concentration (MIC) of 6.25 mg/ml. Furthermore, L. rhamnosus revealed the best antioxidant potentials with IC50 46.59 µg/ml, total phenolic content 172.08 mg/ml and total flavonoid content 17.22 mg/ml. When different concentrations of its supernatant 25, 50 and 100 mg/g were applied, 100 mg/g were able to eliminate C. perfringens EMCC1574 from chicken meat on the 4th day of cold storage. For antagonistic potentials against clostridial infections, this probiotic strain could be recommended for further trials in other applications targeting food safety.