人源双歧杆菌的分离纯化及鉴定

The identification of Bifidobacterium form human feces

利用改良的乳酸细菌(MRS)培养基从健康人群的粪便中进行双歧杆菌的分离筛选。结果表明:在添加有5-溴-4-氯-3-吲哚-β-D-半乳糖苷(X-Gal)的MRS培养基上双歧杆菌的菌落呈典型的乳白色并带有蓝色,其他菌株的菌落呈白色或深蓝色。实验共分离出10株疑似菌株,经生理生化试验和Biolog自动微生物分析系统鉴定,结果发现其中4株为双歧杆菌,这4株菌中有3株为两歧双歧杆菌,1株为长双歧杆菌。和传统MBS培养基相比较,改良MRS培养基能显著提高筛选效率。

A Bifidobacterium strain was separated and raised from the excrement of the healthy adults, using the improved MRS medium. The result showed that the colors were different on the MRS medium with X-Gal,and the Bifidobacterium colonies were milky white with blue background, while other strain colonies were white and dark blue. According to the results of physiological tests and the Biolog automated microbial analysis system,4 strains of Bifidobacterium from 10 were identified, 3 strains were B. bifidum and the other was B. longum. Meanwhile, the research results showed that, compared with the MBS medium, the improved MRS medium could significantly enhance the separation efficiency.