开菲尔粒中醋酸菌的分离鉴定

Isolation and Identification of Acetobacter Bacteria from Kefir Grains

从开菲尔粒中分离出2株醋酸菌FJAT-13764和FJAT-13780。利用形态学观察、生理生化和16SrDNA方法对菌株进行分类鉴定。菌株FJAT-13764和FJAT-13780的菌体形态均为圆端直杆菌,单个或成对,无芽孢,其生理生化特征与醋杆菌属Acetobacter基本一致。经16SrDNA基因序列同源性比较和系统发育分析,鉴定菌株FJAT-13764为Acetobacter orientalis(东方醋酸菌),菌株FJAT-13780为Acetobacter syzygii。

Two Acetobacter strains FJAT-13764 and FJAT-13780 were isolated from kefir grains. The observations with scanning electron microscope showed that both bacteria strains were rod-shaded with round terminals, presented in single or pairs, produced no spores. Their oreralt biochemical and physiological characters indicated that these strains should be placed in the Acetobacter spp. The 16S rDNA sequence analysis indicated that FJAT- 13764 and FJAT-13780 were Acetobacter orientalis and Acetobacter syzygii, respectively. This study is the first report in Acetobacter orientalis isolated from kefir grains, which provides the basic information for further researches on the micro-flora diversity in kefir grain.