The Probiotic Properties in Vitro and Safety Analysis of Streptococcus thermophiles MN-ZLW-002

In this study, the probiotic property in vitro and safety of Streptococcus thermophilus MN-ZLW-002 isolated from Gannan area were analyzed. The results showed that MN-ZLW-002 was well tolerated to artificial gastric juice at pH2.0 and pH3.0, but weakly tolerated to 0.3% bile salt. The cholesterol degradation rate of strain MN-ZLW-002 was 42.66%±2.11%. MN-ZLW-002 was sensitive to chloramphenicol, gentamicin, streptomycin, tetracycline, vancomycin, kanamycin, penicillin, erythromycin and clindamycin. Meanwhile, MN-ZLW-002 acute transoral toxicity was nontoxic. In a conclusion, MN-ZLW-002 is not only non-toxic and has a good tolerance to simulated gastric juice, but also has a strong ability to degrade cholesterol. It can be developed as a functional fermented food raw material and has a great commercial value.