Pseudomonas aeruginosa (P. aeruginosa) is an important opportunistic pathogen that is responsible for many clinical infections in both animals and humans. This study aimed to detect the prevalence of P. aeruginosa in dairy farm's that possess a great importance to dairy industry where it shares in milk spoilage. Evaluation of the efficacy of commonly used disinfectants to control the pathogen in dairy environment and finding a way to overcome high resistance to the used agents. Samples (n = 250) were collected from different environmental components, milk, and milkers' hands. Pathogens were isolated, biofilm was detected and their sensitivity against two commonly used disinfectants and against silver nanoparticles and Virokill AgNPs at different concentrations and contact times were tested. The pathogen significantly prevailed in milk samples (70.0%, P < 0.001). 50 out 74 isolates were biofilm-forming that was significantly obtained from environment (71.8%, P < 0.001). P. aeruginosa showed variable degree of resistance to tested disinfectants but it was significantly sensitive to Virokill AgNPs (200/1000) mg/l at exposure time 24 h (P < 0.001). It was concluded that using Virokill AgNPs in regular sanitation and disinfection of dairy farms, this helps the control of P. aeruginosa subsequently increasing milk quality and improving dairy industry and protecting human health.

Layered double hydroxides (LDH) are promising 2D nanomaterials being investigated for several engineering and biomedical applications. In this work, quinary Zr Al Fe Co Ni LDH and its Al Fe Co Ni LDH quaternary and Fe Co Ni LDH tertiary roots were prepared and characterized. All samples showed an aggregated, layered morphology with zero surface charge and approximately 300 nm of hydrodynamic size. BET surface area of Al Fe Co Ni LDH showed a remarkable value of 143.25 m² g⁻¹ as opposed to 26.2 m² g⁻¹ and 45.4 m² g⁻¹ for Fe Co Ni LDH and Zr Al Fe Co Ni LDH, respectively. The antimicrobial activity of the prepared samples was assessed against the many pathogenic bacteria; Bacillus (B.) subtilis, Escherichia (E.) coli, Haemophilus (H.) influenza, Listeria (L.) monocytogenes, Staphylococcus (S.) aureus, and Streptococcus (St.) pneumonia, and six fungal species. Furthermore, anti-biofilm activity, growth curve assay, and effect of UV illumination were examined against various pathogenic microbes. Zr Al Fe Co Ni displayed remarkable antibacterial activity, as indicated by the lowest values of the minimum inhibitory concentrations (MIC) of 4–166.7 μg mL⁻¹. Results for fungal strains varied in terms of their susceptibilities for the different samples tested. Zn Al Fe Co Ni was able to inhibit the biofilm formation of S. aureus (96.09%), E. coli (98.32%), and Candida (C.) albicans (95.93%). This study shown that certain LDH categories, particularly Zr Al Fe Co Ni, may be promising antibacterial agents against variety of pathogenic microorganisms that cause serious infections.

This study investigated the prevalence of Listeria monocytogenes in retail poultry shops, characterized the antibiotic resistance profile, and detected the genotypic pattern of virulence genes. Broiler meat (n = 90), intestinal content (n = 40), and environmental samples (n = 95) were collected for this study. Besides, hand swabs (n = 20) were obtained from the poultry shop workers and stool samples (n = 40) were collected from the outpatient clinics of Beni-Suef University Hospital, Egypt. The samples were subjected to isolation and identification of L. monocytogenes by conventional bacteriological examinations and biochemical tests, followed by confirmatory identification by the polymerase chain reaction. Among the collected samples (n = 285), L. monocytogenes could be detected in 14.4% (n = 41/285) of the samples, where 30.0% (n = 12/40) of the intestinal content was positive. Similarly, 10.0% (n = 9/90), 15.0% (n = 3/20), and 12.5% (n = 5/40) of the samples of meat, hand swabs, and stools were found positive for L. monocytogenes, respectively. A total of 12 (12.6%) out of 95 environmental samples were positive for L. monocytogenes. Based on the antimicrobial sensitivity profile, most of the recovered isolates were multidrug-resistant against most commonly used antibiotics. The findings conclude that poultry shops play a vital role in transmitting L. monocytogenes to the consumers. Asymptomatic poultry shop workers should draw attention to their potentials for spreading the infection to the consumers through the contaminated carcasses. Low hygienic standards are present in commercial poultry shops that increase the risk of contamination in the sold products.

This study developed a lysozyme–dequalinium chloride-loaded Zn–Fe layered double hydroxide (LDH)–chia seed mucilage matrix for enhanced antimicrobial efficacy and sustained drug delivery. The optimized formulation (15% w/v Zn–Fe LDH–chia seed hybrid) achieved encapsulation efficiencies of 93.30 ± 1.92% (lysozyme) and 88.74 ± 1.71% (dequalinium), with a particle size of 153.77 ± 5.79 nm, PDI of 0.18, and zeta potential of +26.44 ± 1.21 mV, ensuring stability and mucoadhesion. Surface morphology, structure, drug loading, and thermostability were confirmed using various techniques. In vitro release studies showed sustained drug release over 24 h. Antimicrobial assays demonstrated inhibition zones against S. mutans (24.33 ± 2.03 mm), S. aureus (14.67 ± 0.88 mm), S. sobrinus (11.45 ± 0.887 mm), and K. pneumoniae (20.33 ± 2.03 mm). MIC/MBC analysis indicated high susceptibility of K. pneumoniae (MIC = 13.00 ± 2.60 μg mL⁻¹, MBC = 20.83 ± 5.23 μg mL⁻¹, P < 0.001) and S. mutans (MIC = 15.60 ± 1.05 μg mL⁻¹, MBC = 26.07 ± 5.23 μg mL⁻¹, P < 0.01), with S. sobrinus showing moderate sensitivity (MIC = 49.66 ± 4.32 μg mL⁻¹, MBC = 72.93 ± 6.43 μg mL⁻¹). MBC/MIC ratios below 4 confirmed bactericidal action. The formulation reduced S. mutans biofilm formation by 90.1 ± 1.2% at the highest tested concentration. Cytotoxicity evaluation showed a CC50 of 306.6 μg mL⁻¹, demonstrating improved cytocompatibility compared to the free components.