Polyphasic characterization of Enterococcus strains isolated from traditional Moghan cheese in Iran

Traditional Moghan cheese is made from unpasteurized milk in the rural areas and nomadic tribes of Moghan region in Iran. In this study, we used a simple and rapid method for isolation of acid resistant lactic acid bacteria from traditional Moghan cheese. The six distinct isolates differentiated based on RAPD-PCR were identified as members of Enterococcus faecium, E. faecalis, and E.durans species using classical phenotypic and biochemical tests as well as molecular methods. Based on the antibiotic susceptibility, the isolates were classified as resistant, intermediate, and sensitive. Cell-free culture supernatants of isolates showed different antagonistic activity against the growth of some spoilage and food-borne pathogens at two natural and neutralized pH conditions. Considering their tolerance to acid and bile, antagonistic effects on some spoilage and food-borne pathogens and susceptibility to vancomycin, E. faecium strain ABRIINW.M (isolate IE2) and E. faecium strain ABRIINW.N (isolate FE1) are proposed as adjunct cultures to prevent the growth of spoilage and food-borne pathogens. Practical applications This study aimed to provide the first data on prevalence, acquired antibiotic-resistance, and probiotic potential of Enterococcus spp. isolated from Moghan cheese in Iran. Such observations contribute to understanding the functional characteristics of Enterococci isolated from Moghan cheese. We also showed that polyphasic characterization of Enterococci provides significant information for species assignment and could be used as a strategy to differentiate between strains of isolates. The results of our study provide a useful setting for further investigations on antibiotic-resistance and antimicrobial activity of Moghan cheese Enterococci as well as evaluation of their technological activities and probiotic potential.