Study on the Safety of the Strains of Lactasin

OBJECTIVE To explore the safety of the strains of lactasin. METHODS VITEK2 compact automatic microbiological analysis system was used to test drug sensitivity of strains. The plasmid were electrophoresed. The toxicities of strains were tested in mice. RESULTS Enterococcus faecalis 140623 with plasmid had natural drug-resistance to clindamycin and macrolide and was sensitive to penicillin, high concentration of aminoglycoside, quinolones, tetracyclines, glycopeptides, streptogramins, oxazo-lidinone and nitrofurantoin. Enterococcus faecalis CGMCC 1.595 without plasmid was sensitive to the above antibiotics. The results of toxicity test met the requirement of Ch.P 2010. CONCLUSION The strain of lactasin is safe to use, but its source should be supervised and standardized.