瘤胃源枯草芽孢杆菌BX1-12的筛选鉴定及其产酶抑菌活性

Isolation,identification,enzyme production and antibacterial activities of rumen-derived Bacillus subtilis BX1-12

本试验通过筛选瘤胃环境中具产酶抑菌活性的芽孢杆菌,为开发功能型饲用微生态制剂奠定基础。采用可培养的方法从健康高产奶牛瘤胃液中分离芽孢杆菌,并测定其产酶能力及抑菌活性,同时对筛选到的功能菌株进行生理生化和分子生物学鉴定。结果显示:从健康高产奶牛瘤胃液中筛选出一株芽孢杆菌BX1-12,其产纤维素酶、蛋白酶及α-淀粉酶活力分别为27.33、137.54 U/mL和1450.53 U/100 mL,同时该菌具广谱抑菌效果,对大肠杆菌、金黄色葡萄球菌和伤寒沙门氏菌的抑菌圈直径分别为13.62、23.21 mm和25.97 mm。结合Biolog生理生化实验及16S rRNA序列分析,鉴定该菌为枯草芽孢杆菌(Bacillus subtilis)。综上,从健康高产奶牛瘤胃液中分离得到的这株枯草芽孢杆菌BX1-12,具有产多种酶活及广谱抑菌的能力,是一株良好的用于奶牛微生态制剂的候选菌株。

In order to lay a foundation for the development of functional forage microecologics,Bacillus with enzyme-producing and antibacterial activity in rumen environment was screened.Bacillus strains were isolated from rumen fluid of healthy high-yield dairy cows by culturable method,and their enzyme-producing ability and antibacterial activity were determined,meanwhile,the selected functional strains were identified by physiological,biochemical and molecular biology.The results showed that a Bacillus strain BX1-12 identified as Bacillus subtilis were obtained from rumen fluid of healthy high-yield dairy cows.The activities of its cellulase,protease andα-amylase were 27.33,137.54 U/mL and 1450.53 U/100 mL,respectively.Meanwhile,the strain had broad antibacterial activities.The diameters of the inhibition zone against Escherichia coli,Staphylococcus aureus and Salmonella typhi were 13.62,23.21 mm and 25.97 mm,respectively.The results indicated that Bacillus subtilis BX1-12 was a good candidate strain for microecologics of dairy cows with the ability of producing a variety of enzyme activities and a wide-spectrum antimicrobial activity.