灯台树内生放线菌多样性及抗菌活性评价

Diversity and antimicrobial activities of endophytic actinomycetes isolated from Alstonia scholar

从云南西双版纳采集7份灯台树样品,经过表面消毒,用4种分离培养基分离得到105株内生放线菌。经16S rRNA基因序列分析鉴定,分布于7个科9个属。利用5种植物病原真菌指示菌对所有菌株的发酵液进行抗菌活性检测。结果显示,有12.4%、14.3%、11.4%、12.4%、8.6%的菌株分别对镰刀霉、疫霉、赤星霉、苹果炭疽、白色念珠菌有抗性。对3株具有广谱抗菌活性的菌株进行再次发酵和抗菌活性复筛,结果显示这3株的抗菌活性稳定,并可能含有生物碱类化合物。

One hundred and five endophytic actinomycetes were isolated using four different media from surface-sterilized tissues of 7 plants samples of Alstonia scholar collected from Xishuangbanna Yunnan province,southeast China.The results showed that they belong to 9 genera,7 families by 16S rRNA gene sequences analysis.All actinomycete strains fermentation liquids were carried out the an-timicrobial activities test against five plant pathogenic fungi.The results showed that 12.4%,14.3%,11.4%,12.4%,8.6% endophytic actinomycetes presented antimicrobial activity for Fusarium graminearum,Phytophthora nicotianae,Alternaria alternata,Colletotrichum gloeosporioides and Candida albicans,respectively.Three strains with strong antibacterial activities were refermented and rescreened,their antimicrobial activities were stability,and may produce alkaloids.