篦子三尖杉内生真菌的分离鉴定和抑菌活性分析

韩洁 桂艳玲 付强 邹颉 赵杰宏

摘 要：珍稀濒危药用植物篦子三尖杉（Cephalotaxus oliveri Mast）是临床白血病药物三尖杉酯碱和高三尖杉酯碱的重要来源，因此，篦子三尖杉的内生真菌具有潜在的药用价值。通过从篦子三尖杉中分离纯化，筛选出16株外观差异较大的菌株，其中4株无产孢结构。经显微结构和ITS分子鉴定，发现其中11株属于链格孢属。抑菌试验表明，10号菌株对金黄色葡萄球菌的抑制作用较大，11号对白葡萄球菌的抑制作用较大;11号和12号对枯草芽孢杆菌的抑制作用较大;7号对大肠杆菌的抑制作用较大;有5株真菌的抑菌谱较广。筛选的内生真菌具有药用活性，为进一步筛选有药用价值的内生真菌及其代谢产物奠定基础。

关键词：篦子三尖杉;内生真菌;ITS;抑菌活性

Abstract：The rare and endangered medicinal plant Cephalotaxus oliveri Mast is an important source of Harringtonine and Homoharringtonine for clinical leukemic therapy，so that the endophytic fungi of C.oliveri have somewhat potential medicinal value.Here，there were sixteen strains with different appearance screened out by isolation and purification from the leaves and branches of C.oliveri.Among them，there were four strains without sporulation structure，and eleven strains identified as Alternaria by microscopic morphology and ITS identification.The results of bacteriostatic experiment showed that the No.10 strain had greater inhibitory effects on Staphylococcus aureus.The same inhibitory effects were also found for No.11 strain on Staphylococcus albus，the No.11 stain and the No.12 strain on Bacillus subtilis，and the No.7 strain on Escherichia coli.Among which，there were five strains with a wide spectrum of bacteriostatic activity.It provides basis for further screening endophytic fungi for medicinal use.

Keywords：Cephalotaxus oliveri; Endophytic fungi; Internal transcribed spacer; Antimicrobial activity

珍稀瀕危药用植物篦子三尖杉隶属于三尖杉科（Cephalotaxaceae）三尖杉属（Cephalotaxus），为国家二级保护植物，喜温暖湿润的生态环境，多分布在贵州、云南、四川等地海拔300～1500 m的山林中[1]。篦子三尖杉的枝叶含有多种生物碱，其中三尖杉酯碱和高三尖杉酯碱可以有效地治疗急性非淋巴细胞白血病[2]。随着人们的滥砍乱伐和保护不力，资源短缺等问题持续出现。生活在植物根、茎、叶等器官中的内生真菌，在与宿主植物长期“协同进化”过程中，有的内生真菌也具有了生成类似宿主活性物质的能力，如紫杉醇[3]、细胞松弛素[4]、鬼臼毒素[5]、长春新碱[6]、喜树碱[7]等。通过对篦子三尖杉内生真菌开展分离纯化、显微和分子鉴定，以及抑菌活性分析，筛选出有广谱抑菌活性的内生真菌，为深入研究和开发具有药用价值的内生菌株奠定了基础。……