Screening of antibiogram, virulence factors, and biofilm production of and the bio-control role of some probiotics as alternative antibiotics.

Background: Food safety is a serious challenge in the face of increasing population and diminishing resources. is a critical foodborne pathogen characterized by its capability to secret a diverse range of heat-resistant enterotoxins. Antibiotic usage in dairy herds resulted in the occurrence of antimicrobial resistance (AMR) patterns among bacterial species, which were consequently transmitted to humans via dairy products. Lactic acid bacteria (LAB) produce bacteriocins, which provide an excellent source of natural antimicrobials with the further advantage of being environmentally friendly and safe.

Aim: Detection of multidrug resistance (MDR) isolates in concerned samples, molecular characteristics, biofilm production, and the inhibitory role of LAB against it.

Methods: Random samples of raw milk and other dairy products were analyzed for isolation. Phenotypic and genotypic assessment of AMR was performed, in addition to detection of classical enterotoxin genes of . Finally, evaluation of the antimicrobial action of some strains against .

Results: Incidence rates of presumptive in raw milk, Kariesh cheese, and yogurt samples were 50%, 40%, and 60%, respectively. The highest resistance of was to Kanamycin (100%) and Nalidixic acid (89.3%), respectively. (78.66%) of were MDR. 11.1% of carried gene. In concern with enterotoxins genes, PCR showed that examined isolates harbored with a percentage of (22.2%), while was found in (11.1%) of isolates. Regarding biofilm production, (88.88%) of were biofilm producers. Finally, agar well diffusion showed that had the strongest antimicrobial action against with inhibition zone diameter ranging from 18 to 22 mm.

Conclusion: There is a widespread prevalence of MDR in raw milk and dairy products. Production of staphylococcal enterotoxins, as well as biofilm production are responsible for public health risks. Therefore, installing proper hygienic routines and harsh food safety policies at food chain levels is substantial.