Isolation And Identification Of Lactic Acid Bacteria From Traditional Fermented Dairy Products In Mongolia

Microbiological compositions of 189 samples of traditional fermented dairy products collected from 13 diffrernt regions in Mongolia were analyzed in this study. 659 strainsof lactic acid bacteria were isolated from these samples, then identified the species of these bacteria.The counts of LAB in 189 fermented dairy product samples were range from 1.10×103 to 1.08×109cfu/mL.659 strains of LAB were isolated on MRS agar and M17 agar, from 189 dairy product samples, including 415 strains of rod, 244 strains of cocci. They were identified by 16S rRNA sequencing analysis.Streptococcus thermophilus(29.4%), Lactobacillus helveticus(27.3%) and Lactobacillus delbrueckii subsp. bulgaricus(20.9%) were the predominant species among all isolates. Moreover, Lactobacillus fermentum, Leuconostoc lactis were major species, the other isolates were identified as Lactobacillus kefiri, Lactobacillus casei, Lactobacillus plantarum, Lactobacillus diolivorans, Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. mesenteroides, Enterococcus durans, Enterococcus faecalis and Lactobacillus brevis.Samples with different contents, Streptococcus thermophilus,Lactobacillus helveticus和Lactobacillus delbrueckii subsp. bulgaricus were the predominant species.The phenotypic characterizations of LAB were different on MRS agar and M17 agar, the kind of livestock and geographical conditions affected the distribution of LAB in dairy products.