Screening and biological characteristics of excellent lactic acid bacteria from Kefir

Abstract

Four excellent lactic acid bacteria were screened from Kefir. After morphological observation, physical and chemical detection, and 16SrDNA sequence comparison, three strains were preliminarily identified as Lactobacillus Kefir, and one strain was Lactobacillus acidophilus. Two strains were selected to study their biological characteristics. The results showed that the lactic acid bacteria isolated from Kefir had good probiotic properties, with a survival rate of more than 42% after artificial gastric juice digestion for 3 hours and more than 46% after artificial intestinal juice digestion for 6 hours; It has inhibitory effects on intestinal pathogenic bacteria such as Staphylococcus aureus and Escherichia coli; Does not produce hemolysis; There are different levels of resistance to antibiotics.