醉鱼草内生细菌ZJ1的抑菌作用及其脂肽类抑菌代谢产物鉴定

为明确醉鱼草(Buddleja lindleyana Fortune)内生细菌ZJ1的抑菌作用及其抑菌代谢物质组成，本研究测定了ZJ1菌株及其发酵液的抑菌作用，分离、纯化及鉴定了ZJ1菌株的抗菌物质，还观察和测定了ZJ1菌株代谢物处理后的Botrytis cinerea菌丝生长状态和细胞膜通透性。结果表明:ZJ1菌株对10种病原菌均有一定抑制作用，其中，活菌及发酵液均对Monilinia fructicola的抑制率最高，分别达95.69%和94.68%；观察ZJ1菌株代谢物的物理特性发现，其代谢物具有排油能力且出现液滴坍塌现象，进一步检测发现ZJ1菌株脂肽类代谢产物中含有表面活性素和泛革素；以B.cinerea作为指示菌，经ZJ1菌株代谢物处理后，B. cinerea菌丝极少产孢，生长异常，发生断裂；细胞膜通透性增大，渗透物质流出，电导率上升。醉鱼草内生细菌ZJ1表现出良好的抑菌作用，其脂肽类代谢产物的鉴定为ZJ1菌株的进一步开发和利用鉴定了基础。

Antagonism of Endophytic Bacteria ZJ1 from Buddleja lindleyana Fortune and Identification of Antifungal Lipopetide Metabolites

To identify antifungal action of Endophytic Bacteria ZJ1 from Buddleja lindleyana Fortune and its antimicrobial metabolites qualitative composition,the tablet confrontation and growth rate method were used to determine the antifungal action of ZJ1 strain and its fermentation broth to 10 kinds of pathogenic fungi.Medium pressure chromatography was used to isolate and purify the crude extracts of antifungal substances from ZJ1 strain,and LC-MS was used to identify the crude extracts by mass spectrometry.The growth status and membrane permeability of B.cinerea mycelia treated with ZJ1 fermentation broth were measured by microscopic observation and electrical conductivity method.The results showed that ZJ1 strain had certain inhibition to all the 10 fungal pathogens,among them,the inhibition rate of ZJ1 strain and its fermentation broth to M.fructicola were highest,reached 95.69%and 94.68%.The physical characteristics of metabolites of ZJ1 strain were measured and it was found that the metabolites of ZJ1 strain had the ability of discharging oil and the droplet collapse phenomenon occurred.Further tests showed that the metabolites of lipids in ZJ1 strain contained surfactant and ubiquitin.With B.cinerea as indicator pathogenic fungi treated with metabolites of ZJ1 strain,B.cinerea mycelia rarely sporulated,grew abnormally and fractured and the membrane permeability of B.cinerea increased,the permeable material flowed out,the electrical conductivity increased.The endophytic bacteria ZJ1 showed superior antifungal effect,and the identification of its peptide metabolites provided the basis for the further development and utilization of ZJ1 strain.