【摘要】 大叶藻是一种水生单子叶植物,是构成海草床的主要藻类之一。对大叶藻内生放线菌及其活性物质的研究是发现海洋微生物资源和新天然产物的有利途径。通过纯培养的方法,使用2216E等7种培养基,从山东省威海市荣成天鹅湖采集的大叶藻样品中分离出62株内生放线菌,并利用纸片法对金黄色葡萄球菌、白色念珠菌和副溶血性弧菌等7种指示菌进行了抗菌活性筛选,其中RO培养基分离出放线菌的种类和数量都较为丰富。抗菌活性筛选结果表明,48株内生放线菌(占77.42%)至少对1种指示菌表现出一定的抑制作用,36株内生放线菌(占58.06%)抑制2种及2种以上指示菌;并且内生放线菌对革兰氏阳性指示菌(金黄色葡萄球菌和枯草芽孢杆菌)的抗菌效果明显优于革兰氏阴性指示菌。研究结果表明,大叶藻的内生放线菌具有较好的抗菌活性,可以为海洋来源抗生素的研究提供新资源。更多还原

【Abstract】 Zostera marina is a submerged monocotyledonous plant, and it is one of the main seagrasses that constitutes the seagrass bed. It’s a good way to study the endophytic actinomycetes associated with Zostera marina for the discovery of marine microbial resource and novel bioactive natural products. Culture-dependent method was used to isolate endophytic actinomycetes associated with Zostera marina from the Swan Lake of Rongcheng, Weihai, Shandong Province. Seven types of media including 2216 E were used for actinomycete isolation. Antimicrobial activity of the crude extracts of all isolated strains was determined using filter paper method against seven indicator bacterial strains including Staphylococcus aureus,Candida albicans and Vibrio parahaemolyticusthe, etc. A total of 62 endophytic actinomycetes was isolated from Zostera marina, and the endophytic actinomycetes isolated on the RO medium were rich of strains and abundant. Of the 62 strains, 48 strains(77.42% of strains) showed antimicrobial activities against at least one of seven indicator strains. There were 36 strains(58.06% of strains) against two or more kinds of indicator bacteria. Isolated strains exhibited higher antimicrobial activity against Gram-positive bacteria(Staphylococcus aureus and Bacillus subtilis) than against Gram-negative bacteria. Our results suggest that endophytic actinomycetes associated with Zostera marina have good diversity and antimicrobial activity, which may be a new source for the discovery of marine antibiotics.更多还原