Control of biofilm-producing Pseudomonas aeruginosa isolated from dairy farm using Virokill silver nano-based disinfectant as an alternative approach.

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.

Cefotax-magnetic nanoparticles as an alternative approach to control Methicillin-Resistant Staphylococcus aureus (MRSA) from different sources.

This study aimed to evaluate the efficacy of magnetic nanocomposite of cefotax against MRSA. A total of 190 samples were collected from milk, farm personnel and different environmental components from the dairy farm under the study to isolate S. aureus. Cefotax based magnetic nanoparticles was synthetized by the adsorption method and marked using Fourier-transform infrared spectrum (FT-IR), and X-ray diffraction (XRD), then it was characterized using Scanning and Transmission Electron Microscope (SEM and TEM). The obtained results revealed that number of positive samples of S. aureus isolation were 63 (33.1%), mainly from feed manger followed by milk machine swabs (60.0 and 53.3%, respectively) at X2 = 48.83 and P < 0.001. Obtained isolates were identified biochemically and by using molecular assays (PCR), also mec A gene responsible for resistance to cefotax was detected. Testing the sensitivity of 63 isolates of S. aureus showed variable degree of resistance to different tested antibiotics and significant sensitivity to cefotax based magnetic nanoparticles at P < 0.05. It was concluded that dairy environment might act a potential source for transmission of MRSA between human and animal populations. In addition, cefotax based magnetic nanoparticles verified an extreme antimicrobial efficacy against MRSA.

Prevalence, virulence genes, and antimicrobial resistance profile of Listeria monocytogenes isolated from retail poultry shops in Beni-Suef city, Egypt.

OBJECTIVE: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.