Diversified Comparison Of Lactic Acid Bacteria From Traditional Dairy Products In Mongolian And Kazakh In Xinjiang

The production of traditional fermented dairy products depended on the unique geographical environment and humane environment in xinjiang. This kind of traditional dairy products has become an integral part to minority in xinjiang. The method is relatively simple mainly by natural fermentation, traditional fermented dairy products with high nutritional value, unique taste and flavor. It also contains a lot of microorganism resources. So it is very necessary to study the species resources for rich microbial resources and avoid the precious resources of lactic acid bacteria passes. In this study traditional dairy products made by Kazak and Mongolian minority as the object, In order to analyze lactic acid bacteria community structure in traditional dairy products and explore the predominant microbial species, both culture-dependent and culture-independent methods, denaturing gradient gel electrophoresis (DGGE) based on the sequence of16S rDNA V6-V8region gene,were used to examine the total lactic acid bacteria counts. According to the experimental results by culture-dependent and culture-independent methods Analysis of the pros and cons of the two methods in terms of microbial identification. At the same time, to provide referential basis for the development and utilization of lactic acid bacteria, this paper studied the good nature of the lactic acid bacteria.(1)17strains of Kazak yogurt and8strains of Mongolian yogurt were collected from Hebuksaier county in Xinjiang and40strains of Lactobacillus was isolated by traditional method,29strains of them were isolated from Kazak samples, the other11strains were isolated from Mongolian samples, Including Pediococcus acidilactici21strains,Lactobacillus fermentum3stiains,Lactobacillus plantarum9strains,Enterococcus durans6strains,Lactobacillus casei1strains.(2) PCR-DGGE gene sequence analysis method showed:R1-R9stand for Lactococcus lactis, Lactobacillus fermentum, Lactobacillus plantarum, Weissella cib aria,Lactobacillus helveticus,Pediococcus acidilactici, Lactobacillus casei, Lactobacillus crustorum, Enterococcus durans. The dominant bacterial community was Lactobacillus helvecticus.(3)13strains of lactic acid bacteria isolated from traditional fermented were selected to measure the bacteriostatic activity by Oxford cup method, Results showed that the13strains of lactic acid bacteria had certain bacteriostatic effect to Saccharomyces cerevisiaet, Escherichia coli, Bacillus subtilis, Listeria monocytogenes and Staphylococcus aureus, but had no effect to Aspergillus niger and Penicillium.sp. Pediococcus acidilactici (H3-3,H1-4,M1-2)had the biggest inhibition zone. Lactobacillus fermentum (H1-2,H8-13) and Lactobacillus casei (H5-8) bacteriostasis effect is not very obvious, lactic acid was the major inhibitory effect to Saccharomyces cerevisiae, Escherichia coli, Bacillus subtilis, Listeria monocytogenes and Staphylococcus aureus.(4) Selected seven strains of lactic acid bacteria resistant to acid and bile salt resistance experiment, the results showed that most lactic acid bacteria has a certain degree of tolerance on human gastric juices and artificial intestinal juice.