Interspecies diversity, safety and probiotic potential of bacteriocinogenic Enterococcus faecium isolated from dairy food and human faeces

In the present study 14 bacteriocinogenic strains of Enterococcus faecium isolated from dairy foods and faecal sample were evaluated for the presence of virulence determinants, production of biogenic amines and their susceptibility to various antibiotics. Genetic diversity among them was evaluated by RAPD-PCR method. Further, they were evaluated for their probiotic potential under in vitro trials. The efaAfm was the only virulence trait detected in all E. faecium and tyramine was the only biogenic amine produced by 9 tested strains. No strain was resistant to all antibiotics and for some strains, multiple resistances were observed. E. faecium FH 99 showed highest good ability to tolerate acid and bile, while good bile salt hydrolase activity and were able to assimilate cholesterol from growth media. These results suggest that the tested E. faecium are generally free from virulence traits and having good probiotic potential and may be exploit in dairy industry and probiotic preparations.