The Diversity Of Lactic Acid Bacteria In Dairy Products From Xinjiang

Traditional dairy products is an indispensable part of nomadic life in Xinjiang.Lactic acid bacteria is the key of fermenting traditional dairy products.The research on the diversity of lactic acid bacteria in dairy products of nomads in Xinjiang provides a theoretical basis for the development and utilization of lactic acid bacteria resources.In this study,the composition of lactic acid bacteria in 93 dairy products collected from nomads in Xinjiang was analyzed,based on Pacbio SMRT sequencing technology and lactic acid bacteria specific primers,revealing the diversity of lactic acid bacteria in dairy products in Xinjiang to a certain extent.The results were shown as follows:(1)The dominant species of lactic acid bacteria in dairy products from Xinjiang were Lactobacillus helveticus,Lactobacillus delbrueckii,Streptococcus thermophilus,Lactococcus lactis,Lactobacillus kefiranofaciens and Lactococcus laudensis,but the composition of the lactic acid bacteria flora in the dairy products was different.(2)The 93 dairy products could be divided into 4 clusters according to UPGMA clustering based on Uni Frac distance.The alpha diversity of the 4 clusters was significantly different.The cluster1 only included 3 dairy products whose dominant genus were Lactococcus.The dominant species of cluster1 were Lactococcus lactis,Lactococcus laudensis,Lactococcus raffinolactis,Lactobacillus helveticus and Streptococcus thermophilus.The dominant genus of other cluster was Lactobacillus,which was different from cluster1.The dairy products of cluster2 and cluster3 were mostly yoghurts,and included all of the yoghurt in 93 dairy products.The dominant species of cluster2 were Lactobacillus delbrueckii,Lactobacillus helveticus and Streptococcus thermophilus,The dominant species of cluster3 were Lactobacillus delbrueckii,Lactobacillus helveticus and Streptococcus thermophilus.And the dairy products in cluster4 were all Koumiss of the 93 dairy products,the dominant species of cluster4 were Lactobacillus helveticus,Lactobacillus kefiranofaciens,Lactococcus lactis,Streptococcus thermophilus,Lactobacillus delbrueckii,Enterococcus faecalis,Lactobacillus kefiri and Lactobacillus pontis.Some of low-abundance lactic acid bacteria strains were found.(3)The analysis of the differences among the 4 clusters showed that the relative abundance of Lactococcus lactis,Lactococcus raffinolactis and Enterococcus faecium in cluster1 was significantly higher than that in other clusters,and the relative abundance of Lactobacillus leichmannii,Streptococcus thermophilus and Streptococcus salivarius in cluster2 was significantly higher than that in other cluster.The relative abundance of Lactobacillus helveticus and Lactobacillus delbrueckii in cluster3 was significantly higher than that in other clusters,and the relative abundance of Lactococcus garvieae,Lactobacillus helveticus,Lactobacillus kefiranofaciens,Lactobacillus kefiri,Lactobacillus pontis and Lactobacillus parakefiri in cluster4 was significantly higher than that in other cluster.And the correlation between the species above were significant.The research on the diversity of lactic acid bacteria in dairy products of nomads in Xinjiang provided a theoretical basis for the development and utilization of lactic acid bacteria resources.