松萝地衣体共生菌的分离纯化及抗细菌活性的初步筛选

摘要

[目的]分离筛选具有抗菌活性的松萝地衣体共生菌[方法]在确定松萝地衣体共生菌分离最佳步骤的基础上,采用2种培养基进行分离和纯化.采用滤纸片法测定分离物3种不同培养基的发酵液对枯草芽孢杆菌、大肠杆菌以及金黄色葡萄球菌的抑制效果.[结果]经5％次氯酸钠浸泡90s对松萝地衣体表面消毒后,采用PDA培养基分离出的松萝地衣体分离物多样性比MEA培养基分离出的好；分离得到的6株分离物均对供试菌具有一定抑制作用,但不同成分的发酵培养基对同一株菌的发酵产物活性有一定影响.[结论]分离得到的松萝地衣体分离物具有良好的抗菌活性,从松萝地衣体分离物中寻找杀菌活性物质是很有研究价值的.%[ Objective ] The aim was to isolate and screen Usnea lichen symbiotic fungi that have bacteriostatic activities. [ Methods ] Based on the optimal procedures for isolating Usnea lichen symbiotic fungi,two kinds of media were used for isolation and purification. The bacteriostatic activities of the fermentation broth from three different media of isolates on Bacillus subtilis, Escherichia coli and Staphylococcus aureus were determined by means of filter paper. [ Result] After soaking lichen Usnea with 5% of sodium hypochlorite for 90 s for surface-sterilization, the diversity of Usnea lichen isolates from PDA medium was better than those from MEA medium. Six isolates all had some bacteriostasis to the tested bacteria, but the different components of medium have some influence on fermentation products' activity of the same bacterium. [Conclusion] The obtained Usnea lichen isolates have good bacteriostatic activity, and it has great research value for looking for bactericidal substances from the lichen Usnea.