刺五加内生细菌的分离及其抑菌活性研究

Isolation of endophytic bacteria from Acanthopanax senticosus and their antimicrobial activities

目的:研究药用植物刺五加内生细菌的分布,并对刺五加内生细菌发酵液进行抑菌活性筛选,为创制新药提供参考。方法:选取大肠杆菌等12株试验菌株,采用滤纸片法对刺五加内生细菌次生代谢产物的抑菌活性进行筛选。结果:从刺五加根茎中分离得到了25株内生细菌,其中有8株内生细菌的发酵液对12株试验菌表现出不同的抑菌活性,占总分离菌株的32%;对抑菌效果较好的内生细菌CR10及CR15通过形态特征观察、生理生化特性鉴定及16S r DNA序列同源性分析,刺五加内生细菌CR10及CR15为枯草芽孢杆菌(Bacillus subtilis)。结论:刺五加内生细菌发酵产物具有较好抑菌活性,可作为新资源从中寻找新型抗菌物质。

Objective： To investigate the diversity of endophytic bacteria from Acanthopanax senticosus and the antimicrobial activity of their secondary metabolites in order to find novel compounds. Methods： A paper disc diffusion method was used to test the antimicrobial activities of endophytic bacteria＇s secondary metabolites against 12 human pathogenic microbes. Results： Among 25 strains of endophytic bacteria isolated from Acanthopanax senti- cosus, 8 strains （32% of the total strains isolated） showed antimicrobial activities against the 12 human pathogenic microbes. Meanwhile, CR10 and CR15 were identified as Bacillus subtilis by the 16S rDNA sequence homology and their physiological and biochemical characteristics, respectively. Conclusion： Diverse antimicrobial natural prod- ucts exist in endophytic bacteria from Acanthopanax senticosus, which may be the resources of new antimicrobial products.