牛源肠道益生菌芽孢杆菌BN-9菌株的分离鉴定

Separating and Identification of Probiotics Bacillus Strains BN-9 from Bovine Intestine

从健康牛的粪便中筛选出对大肠杆菌(Escherichia coli)有抑制作用的芽孢杆菌,并对其进行鉴定。以大肠杆菌为指示菌进行初筛和复筛,采用SPSS软件对复筛结果进行显著性分析,选择抑制大肠杆菌活性较强的菌株。经过形态观察、生理生化试验和16S rDNA全序列分析鉴定其种属;采用稀释活菌计数法测绘活性菌株的生长曲线,利用SPSS软件结合修正的Gompertz方程和Logistic方程对生长曲线进行拟合,以获得活性菌株的生长动力学参数。经过鉴定,筛选得到的对大肠杆菌有较强抑制作用的芽孢杆菌BN-9菌株属于解淀粉芽孢杆菌(Bacillus amyloliquefaciens);采用SPSS软件拟合得到的生长曲线的相关系数(R)在0.985以上。筛选并鉴定出强烈抑制大肠杆菌的牛源肠道益生菌BN-9;采用SPSS软件可以较准确地预测这些菌株的生长动力学参数。

Bacillus which could strongly inhibit Escherichia coli was separated and identified from healthy bovine intestine feces.Using Escherichia coli as indicative bacteria,Bacillus strains that could strongly inhibit Escherichia coli were pre-screened and secondary screened.Significance analysis to secondary screening result was calculated by SPSS software.Identi-fication of active strains were done by morphological observation,physiological biochemical test and 16S rDNA sequence analysis.Growth curves of these strains were drawn by diluted viable count method.The curve fitting was done to obtain growth kinetic parameters of these strains by using SPSS software combining modified Gompertz equation and modified Logis-tic equation.Strain BN-9 wase obtained which could strongly inhibit Escherichia coli from healthy bovine intestine feces.Strain BN-9 was identified to Bacillus amyloliquefaciens.The correlation coefficient of growth curves fitted by SPSS software was above 0.985.Strain BN-9 as probiotics was obtained.Growth kinetic parameters of strain BN-9 could be predicted ac-curately by SPSS software.