乌拉尔甘草内生真菌的分离及其抑菌活性研究

Study on Isolation of Endophytic Fungi from Glycyrrhiza uralensis Fisch. and Their Antimicrobial Activity

研究乌拉尔甘草内生真菌及其次生代谢产物的抑菌活性,旨在获得有良好抑菌活性的菌株,寻找新型抗菌物质。以大肠杆菌、枯草芽孢杆菌、金色葡萄球菌、短小芽孢杆菌、铜绿假单孢菌、单增李斯特菌、肺炎克雷伯菌、鲍曼不动杆菌、酿脓链球菌、屎肠球菌、粪肠球菌和白假丝酵母为试验菌株,用菌饼法及纸片法对分离的真菌及其次生代谢产物进行抑菌试验。从乌拉尔甘草中分离到46株内生真菌,其中34株内生真菌对指示菌表现出不同的抑菌活性,占总分离菌株的74%;20株内生真菌的发酵液对指示菌株也有一定的抑制作用,占总分离菌株的43%。乌拉尔甘草的内生真菌及其次生代谢产物中存在着丰富的抑菌天然活性物质,这可为新型抗菌物质提供资源。

In order to get the strains with good antimicrobial activity, the endophytic fungi from Glycyrrhiza uralens/s Fisch. and their secondary metabolites were investigated. Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Bacillus pumilus, Pseudomonas aeruginosa, Listeria monocytogenes, Klebsiella penumoniae, Acinetobacter baumannii, Streptococcus pyogenes, Enterococcus faecium, Enterococcus facalis and Candida albicans were selected as the indicators for human pathogenic microbes. Antimicrobial tests of the isolated endophytic fungi and their secondary metabolites were carried out by colony disc method and paper disc diffusion method. Among 46 strains of endophytic fungi isolated from Glycyrrhiza uralensis Fisch., 34 strains （74% of the total strains isolated） showed the different antimicrobial activity against of 12 human pathogenic microbes, and the secondary metabolites of 20 strains at least （43% of the total strains isolated） presented the antimicrobial activity against of 12 human pathogenic microbes. Diverse antimicrobial natural products are existed in endophytic fungi and their secondary metabolites from Glycyrrhiza uralensis Fisch., which can be the resources for new antimicrobial products.