Resources And Taxonomy Of Lactic Acid Bacteria Isolated From Sauerkraut In Hulan,Harbin

Natural fermented sauerkraut produced by fermentation with lactic acid bacteria which existing in nature.Sauerkraut is rich in nutrition and contains a variety of lactic acid bacteria.It is a special food in northeast China.Lactic acid bacteria is the main bacteria in the process of sauerkraut production,which plays a leading role in the whole process.Strengthen the understanding of its biodiversity is important for the development of functional lactic acid bacteria resources in sauerkraut.In this study,247 strains of lactic acid bacteria were isolated from naturally fermented sauerkraut juice in northeast China,and their species were identified for further understand the diversity of lactic acid bacteria in sauerkraut.In this study,16 S r RNA gene sequence analysis,phe S(coding phenylalanine-t RNA synthase subunit)gene sequence analysis and rpo A(coding RNA polymerase subunit)gene sequence analysis were used for identify species.The 16 S r RNA gene sequence and phe S gene sequencing were performed on 247 isolated strains,among which 236 strains were successfully sequenced by phe S gene sequence,and the remaining strains were sequenced by rpo A gene sequence.The results showed that 247 strains were distributed in 21 known species and 5 unknown species.It was distributed in 4 genera: Lactococcus,Enterococcus,Lactobacillus and Pediococcus.The 21 species were: Lactobacillus amylotrophicus?L.paracasei?L.amylophilus?L.plantarum?L.coryniformis?L.curvatus?L.oryzae ? L.malefermentans ? L.buchneri ? L.nodensis ? L.concavus ? L.koreensis ? L.parabuchneri?L.nenjiangensis?L.nasuensis?L.brevis?L.xiangfangensis?Lactococcus lactis?Enterococcus xiangfangensis ? Enterococcus gilvus and Pediococcus parvulus.Lactobacillus coryniformis is the dominant strain among the identified species,2 strains belonged to Enterococcus,1 strain belonged to Pediococcus,1 strain belonged to Lactococcus,and the rest were all belonged to Lactobacillus.In the 16 S r RNA gene sequencing,the unknown species 1 represented by zw163 was in close phylogenetic branches to L.sharpeae,L.songhuajiangensis,L.pantheris and L.thailandensis.zw152 represents the unknown species 2,which is closely related to L.camelliae and L.nasuensis in the 16 S r RNA gene sequencing.The unknown species 3 and 4 represented by zw101 and zw326 were closely related to the phylogenetic branches of L.backii,L.coryniformis and L.iwatensis in 16 S r RNA gene sequencing.The unknown species zw10 was most closely related to L.parabrevis in 16 S r RNA gene sequencing.This study increases the understanding of the diversity of lactic acid bacteria in sauerkraut,and the discovery of new species expands the classification system of lactic acid bacteria,making the classification system of lactic acid bacteria more abundant.The isolated and preserved lactobacillus strains can be used for screening starter strains in the industrial production of sauerkraut.