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Milk, a nutritious global important food commodity, serves as an excellent medium for microbial growth as well. The foodborne pathogen Staphylococcus aureus is a commensal member of human microflora that enters the food chain through poor hygienic practices and cross contamination and causes various clinical manifestations in humans. During this study, raw milk and swab samples (milker's hand, udder, towel, milking bucket, and farm floor) were collected from four middle-scale buffalo dairy farms. The results revealed S. aureus presence in 11.6% ( n = 56/448) bucket raw milk samples and 2.6% ( n = 12/448) udder raw milk samples. Contrarily, S. aureus prevalence was significantly higher in farm floors (100%, n = 84/84), towel (35.7%, n = 10/28), milking bucket (11.6%, n = 56/448), milker's hand (10.7%, n = 3/28), and udder swab samples (4.0%, n = 18/448). The chi-square test yielded p values of 0.000, 0.005, and 0.0011 for udder raw milk, udder swab, and milker's hand swab, respectively. The p values of the milking bucket ( p = 0.048) and farm floors ( p = 0.0183) confirmed their possible role in S. aureus cross contamination. Gene amplifications of nuclease and enterotoxin A indicate potential virulence of S. aureus isolates in collected samples. Antibiotic susceptibility testing revealed multidrug resistance in 44% ( n = 239) of S. aureus isolates with the highest resistance of 61% against penicillin. Resistance against ampicillin, streptomycin, and lincomycin was observed. Fewer S. aureus isolates were resistant to kanamycin and erythromycin, whereas the lowest number of resistant isolates was observed against chloramphenicol. A high prevalence of S. aureus in the farm environment and milking equipment suggested the cross contamination of potentially enterotoxin-producing and multidrug-resistant S. aureus to raw milk. Therefore, good hygiene practices should be enforced to avoid foodborne and zoonotic infections.

Microbial biopolymers have emerged as promising solutions for environmental pollution-related human health issues. Poly-γ-glutamic acid (γ-PGA), a natural anionic polymeric compound, is composed of highly viscous homo-polyamide of D and L-glutamic acid units. The extracellular water solubility of PGA biopolymer facilitates its complete biodegradation and makes it safe for humans. The unique properties have enabled its applications in healthcare, pharmaceuticals, water treatment, foods, and other domains. It is applied as a thickener, taste-masking agent, stabilizer, texture modifier, moisturizer, bitterness-reducing agent, probiotics cryoprotectant, and protein crystallization agent in food industries. γ-PGA is employed as a biological adhesive, drug carrier, and non-viral vector for safe gene delivery in tissue engineering, pharmaceuticals, and medicine. It is also used as a moisturizer to improve the quality of hair care and skincare cosmetic products. In agriculture, it serves as an ideal stabilizer, environment-friendly fertilizer synergist, plant-growth promoter, metal biosorbent in soil washing, and animal feed additive to reduce body fat and enhance egg-shell strength., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elbanna, Alsulami, Neyaz and Abulreesh.)

Background: Aflatoxin (AF), a metabolite of Aspergillus flavus , is injurious to vital body organs. The bacterial defense against such mycotoxins has attracted significant attention. Lactic acid bacteria (LAB) are known to ameliorate AF toxicity., Methods: Thirty adult male rats were divided into six groups (five each) to perform the experiments. The control (Co) group was fed a basal diet and water. Each of the following periods lasted 21 days: the milk (MK) group orally received milk (500 µL); LAB suspension (500 µL) containing 10 7 cfu/mL was orally provided to the LAB group; AF (0.5 mg/kg) was orally given to the AF group; and a combination of AF and LAB was administered to the AF + LAB group. The AF/LAB group was initially given AF for 21 days, followed by LAB for the same period. Finally, the rats were dissected to retrieve blood and tissue samples for hematological, biochemical, and histological studies., Results: The results revealed a significant decrease in RBCs, lymphocytes, total proteins, eosinophil count, albumin, and uric acid, whereas the levels of WBCs, monocytes, neutrophils, creatinine, urea, aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase, lactate dehydrogenase, and creatinine kinase significantly increased in the AF group in comparison to the control group. The histological examination of the AF group revealed necrosis and apoptosis of the kidney's glomeruli and renal tubules, nuclei vacuolization and apoptosis of hepatocytes, congestion of the liver's dilated portal vein, lymphoid depletion in the white pulp, localized hemorrhages, hemosiderin pigment deposition in the spleen, and vacuolization of seminiferous tubules with a complete loss of testis spermatogenic cells. Meanwhile, protective and therapeutic LAB administration in AF-treated rats improved the hematological, biochemical, and histological changes., Conclusions: The study revealed LAB-based amelioration to AFB1-induced disruptions of the kidney, liver, spleen, and testis by inhibiting tissue damage. The therapeutic effects of LAB were comparatively more pronounced than the protective effects.

This study investigated different amino acid-based surfactants (AASs), also known as biosurfactants, including sodium N-dodecyl asparagine (AS), sodium N-dodecyl tryptophan (TS), and sodium N-dodecyl histidine (HS) for their potential anticorrosion, antibacterial, and antidermatophyte properties. The chemical and electrochemical techniques were employed to examine the copper corrosion inhibition efficacy in H 2 SO 4 (1.0 M) solution at 298 K. The results indicated their promising corrosion inhibition efficiencies (% IEs), which varied with the biosurfactant structures and concentrations, and the concentrations of corrosive medium. Higher % IEs values were attributed to the surfactant adsorption on the copper surface and the production of a protective film. The adsorption was in agreement with Langmuir adsorption isotherm. The kinetics and mechanisms of copper corrosion and its inhibition by the examined AASs were illuminated. The surfactants behaved as mixed-kind inhibitors with minor anodic priority. The values of % IEs gained from weight loss technique at a 500 ppm of the tested surfactants were set to be 81, 83 and 88 for AS, HS and TS, respectively. The values of % IEs acquired from all the applied techniques were almost consistent which were increased in the order: TS > HS ≥ AS, establishing the validity of this study. These surfactants also exhibited strong broad-spectrum activities against pathogenic Gram-negative and Gram-positive bacteria and dermatophytes. HS exhibited the highest antimicrobial activity followed by TS, and AS. The sensitivity of pathogenic bacteria varied against tested AASs. Shigella dysenteriae and Trichophyton mantigrophytes were found to be the most sensitive pathogens. HS exhibited the highest antibacterial activity against Shigella dysenteriae, Bacillus cereus, E. coli, K. pneumoniae, and S. aureus through the formation of clear zones of 70, 50, 40, 39, and 35 mm diameters, respectively. AASs also exhibited strong antifungal activity against all the tested dermatophyte molds and fungi. HS caused the inhibition zones of 62, 57, 56, 48, and 36 mm diameters against Trichophyton mantigrophytes, Trichophyton rubrum, Candida albicans, Trichosporon cataneum, and Cryptococcus neoformans, respectively. AASs minimal lethal concentrations ranged between 16 to 128 µg/ml. HS presented the lowest value (16 µg/ml) against tested pathogens followed by TS (64 µg/ml), and AS (128 µg/ml). Therefore, AASs, especially HS, could serve as an effective alternative antimicrobial agent against food-borne pathogenic bacteria and skin infections-associated dermatophyte fungi., (© 2023. The Author(s).)

Milk is a putrescible commodity that is extremely prone to microbial contamination. Primarily, milk and dairy products are believed to be easily contaminated by pathogenic microorganisms, including Listeria monocytogenes , Salmonella spp., and Staphylococcus aureus . The microbiological quality of raw milk and dairy products regarding foodborne pathogens is of paramount importance due to concern of human health. In this study 400 buffalo raw milk samples were screened for assessing the prevalence of L. monocytogenes , Salmonella spp., and S. aureus . This study implemented uniplex-polymerase chain reaction (u-PCR) and multiplex-polymerase chain reaction (m-PCR) assays for the fast simultaneous detection of these pathogens comparing to the conventional culturing methods. Raw milk samples were found contaminated with the prevalence of 2.2%, 4.0%, and 14.2% for L. monocytogenes , Salmonella spp., and S. aureus , respectively. These pathogens were detected with the optimized polymerase chain reaction assays after 6 h of enrichment. u-PCR and m-PCR demonstrated the limit of detection as 10 4 , 10 2 , and 10 cells/mL after 6, 12, 18, and 24 h for each culture of the pathogens. A high sensitivity (10 colony-forming unit [CFU]/mL) of the m-PCR protocol was noted. The developed protocol is a cost-effective and rapid method for the simultaneous detection of pathogens associated with raw milk and dairy industries.

To explore the prevalence of multidrug-resistant community-associated uropathogenic Escherichia coli (UPEC) and their virulence factors in Western Saudi Arabia. A total of 1,000 urine samples were examined for the presence of E. coli by selective plating on MacConkey, CLED, and sheep blood agar. Antimicrobial susceptibility patterns were determined using Vitek ® 2 Compact (MIC) and the disc diffusion method with Mueller-Hinton agar. Genes encoding virulence factors ( kpsMTII , traT , sat , csgA , vat , and iutA ) were detected by PCR. The overall prevalence of UTI-associated E. coli was low, and a higher prevalence was detected in samples of female origin. Many of the isolates exhibited resistance to norfloxacin, and 60% of the isolates showed resistance to ampicillin. No resistance to imipenem, meropenem, or ertapenem was detected. In general, half of the isolates showed multiple resistance patterns. UPEC exhibited a weak ability to form biofilms, where no correlation was observed between multidrug resistance and biofilm-forming ability. All uropathogenic E. coli isolates carried the kpsMTII , iutA , traT , and csgA genes, whereas the low number of the isolates harbored the sat and vat genes. The diversity of virulence factors harbored by community-associated UPEC may render them more virulent and further explain the recurrence/relapse cases among community-associated UITs. To the best of our knowledge, this study constitutes the first exploration of virulence, biofilm-forming ability, and its association with multidrug resistance among UPEC isolates in Saudi Arabia. Further investigations are needed to elucidate the epidemiology of community-associated UPEC in Saudi Arabia., (© 2022 Sara H. Arafa et al., published by Sciendo.)

Biosynthesis of silver nanoparticles (AgNPs) is emerging as a simple and eco-friendly alternative to conventional chemical synthesis methods. The role of AgNPs is expanding as antimicrobial and anticancer agents, sensors, nanoelectronic devices, and imaging contrast agents. In this study, biogenic AgNPs were synthesized using extracts of different marine algae species, including Ulva rigida (green alga), Cystoseira myrica (brown alga), and Gracilaria foliifera (red alga), as reducing and capping agents. The Physiochemical properties, cytotoxicity, anticancer and antimicrobial activities of the biosynthesized AgNPs were assessed. Surface plasmonic bands of the biosynthesized AgNPs capped with U. rigida, C. myrica, and G. foliifera extracts were visually observed to determine a colour change, and their peaks were observed at 424 nm, 409 nm, and 415 nm, respectively, by UV-Vis spectroscopy; transmission electron microscopy (TEM) indicated an almost spherical shape of AgNPs with nanoscale sizes of 12 nm, 17 nm, and 24 nm, respectively. Fourier transform-infrared (FTIR) spectroscopy analysis suggested that different molecules attached to AgNPs through OH, C=O, and amide groups. The major constituents of the aqueous algal extracts included, terpenoids, polyphenols, sulfonates, polysaccharides, fatty acids, chlorophylls, amide proteins, flavonoids, carotenoids, aliphatic fluoro compounds, volatile compounds, alkalines, pyruvic acid and agar groups. The cytotoxicity and anticancer activities of the biosynthesized AgNPs were assessed using Artemia salina nauplii, normal skin cell lines (HFb-4), and breast cancer cell lines (MCF-7 cell line). The lethality was found to be directly proportional to the AgNP concentration. The IC 50 values of C. myrica and G. foliifera AgNPs against A. saline nauplii were 5 and 10 μg ml -1 after 4 h and 16 h, respectively, whereas U. rigida AgNPs did not exhibit cytotoxic effects. Anticancer activity of the biosynthesized AgNPs was dose dependent. The IC 50 values of the biosynthesized AgNPs were 13, 13, and 43 µg ml -1 for U. rigida, C. myrica, and G. foliifera, respectively. U. rigida AgNPs particularly exhibited potent anticancer activity (92.62%) against a human breast adenocarcinoma cell line (MCF-7) with high selectivity compared the normal cells (IC 50  = 13 µg/ml, SI = 3.2), followed by C. myrica AgNPs (IC 50  = 13 µg/ml, SI = 3.07). Furthermore, the biosynthesized AgNPs exhibited strong antifungal activity against dermatophyte pathogenic moulds and mild antibacterial activity against the food borne pathogen bacteria. The highest antimicrobial activity was recorded for the U. rigida AgNPs, followed by those capped with C. myrica and G. foliifera extracts, respectively. AgNPs capped with the U. rigida extract exhibited the highest antimicrobial activity against Trichophyton mantigrophytes (40 mm), followed by Trichosporon cataneum (30 mm) and E. coli (19 mm), with minimal lethal concentration of 32 and 64 μg ml -1 respectively. The study finally revealed that extracts of marine algal species, particularly U. rigida extracts, could be effectively used as reducing agents for the green synthesis of AgNPs. These AgNPs are considered efficient alternative antidermatophytes for skin infections and anticancer agents against the MCF-7 cell line., (© 2022. The Author(s).)

Imprudent and overuse of clinically relevant antibiotics in agriculture, veterinary and medical sectors contribute to the global epidemic increase in antimicrobial resistance (AMR). There is a growing concern among researchers and stakeholders that the environment acts as an AMR reservoir and plays a key role in the dissemination of antimicrobial resistance genes (ARGs). Various drivers are contributing factors to the spread of antibiotic-resistant bacteria and their ARGs either directly through antimicrobial drug use in health care, agriculture/livestock and the environment or antibiotic residues released from various domestic settings. Resistant micro-organisms and their resistance genes enter the soil, air, water and sediments through various routes or hotspots such as hospital wastewater, agricultural waste or wastewater treatment plants. Global mitigation strategies primarily involve the identification of high-risk environments that are responsible for the evolution and spread of resistance. Subsequently, AMR transmission is affected by the standards of infection control, sanitation, access to clean water, access to assured quality antimicrobials and diagnostics, travel and migration. This review provides a brief description of AMR as a global concern and the possible contribution of different environmental drivers to the transmission of antibiotic-resistant bacteria or ARGs through various mechanisms. We also aim to highlight the key knowledge gaps that hinder environmental regulators and mitigation strategies in delivering environmental protection against AMR., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)