Studies On Biological Activity And Isolation And Identification Of Lactic Acid Bacteria In The Kumiss

Forty-seven strains of bacteria were isolated from the samples of Kumiss products collected from the pastoral area in Xilin Guole,and its biological properties were studied. 41 stains of the Lactic acid bacteria was isolated from 18 samples of Lactic acid bacteria freeze-dry products, in which 32 stains were lactobacillus, and belonged to 12 species of 1 genus respectively; 9 stains were lactococcus , and belonged to 6 species of 3 genus respectively . 6 stains weren′t lactic acid bacteria. The ability of tolerance to acid and bile salts of lactobacillus was examined. The results showed that lactobacillus were resistant to pH 3.0~5.0 , and tolerant to 0.2~ 0.4% bile salts . The growth carve of strains was : slow–moving period . logarithm growth period and invariable period were 4 h ,4~14 h and after 14 h respectively . Inhibiting bacteria test of leavening and metabolite of 10 strains lactobacillus Showed that leavening and metsbolite had antagonistic activity to bacillus subtilis ,Staphylococcus and Escherichia coli ,diameter of inhibiting ring were 10.2~15.7 mm,10.0~13.0 mm,10.2~13.3 mm respectively. Leavening and metsbolite had antagonistic activity at pH 1.0~5.0, and when pH was lower, the antagonistic activity of metabolite was higher ; they had not antagonistic activity at pH 5.0~10.0 . The content of Exopolysaccharides of RDQ-2 was higher than other bacterium.