| 7 strains of lactic acid bacteria separated from 9 samples of mare’s milk which were collected from pastoral area of Xilingole in Inner Mongolia were identificated in this study. Based on the results of physiological, biochemical characteristics and molecular biology tests,among these 7 strains,there are 2 strains of Enterococcus raffinosus (cottonseed sugar Enterococcus),2 strains of Enterococcus gilvus.Meanwhile, the other 3 strains are Enterococcus durans (strong), Enterococcus dispar (abnormal aureus), Enterococcus italicus(Italy).All of those 7 strains are resistant to sailt, heat and bile salt. Moreover,those strains can grow in the environment which has a pH between 4.5 and 9.6.Quantitative detection of VB12 in fermentation broth of Enterococcus durans HZ9 which were isolated from Kumiss and the factors affecting its production and detection were studied by using microbiological method in this papaer. These results show that the taken method has a linear range between 0.001ng/mL and 0.010 ng/mL. VB12 starts to inhibit the Lactobacillus leichmannii when it is 0.080ng.In this range, the content of VB12 in HZ9 fermentation can be measured as 7.670)μg/L. The best concentration of Co2+ to improve the synthetic of VB12 while it increases to 15.50μg/L in HZ9. It has obvious inhibition on Lactobacillus leichmannii when the concentrate of sodium metabisulfite is lmg/mL. There is no obvious inhibition or promotion on the growth of Lactobacillus leichmannii when the concentrate of Co2+is around 0～5000μg/mL. |
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