博落回内生真菌Chaetomium cupreum ZJWCF079次生代谢产物研究

A study on the secondary metabolites of endophytic fungus Chaetomium cupreum ZJWCF079 in Macleaya cordata

目的对博落回一株具有较强抗菌活性的内生真菌角毛壳Chaetomium cupreum ZJWCF079的代谢产物进行研究。方法对内生真菌Chaetomium cupreum ZJWCF079发酵产物进行溶媒萃取、硅胶柱层析、Sephadex LH-20等手段,同时结合活性跟踪分离的方法找到具有活性的单体化合物。所得单体化合物经进行现代波谱解析,确定化合物结构,并进一步采用平板生长速率法测定对多种植物病原菌的抑制作用。结果首次从内生真菌角毛壳代谢产物中分离获得化合物麦角甾烷-5,7,22-三烯-3-醇(1),活性测试表明,该化合物对核盘菌、灰葡萄孢有中等抑制作用,EC50值分别为125μg/mL、190μg/mL。对终极腐霉、立枯丝核菌、尖孢镰孢均没有抑制作用,EC50值均大于500μg/mL。结论药用植物内生真菌是获得抗菌活性天然产物的重要来源。

Objective The study was intended to understand the bioactive metabolites of endophytic fungus Chaetomium cupreum ZJWCF079 with strong antifungal activity in Macleaya cordata. Method The fermentation broth of endophytic fungus Chaetomium cupreum ZJWCF079 was isolated and purified through solvent extraction, silica gel column chromatography, Sephadex LH-20 and bioassay-guided fractionation. The compound was elucidated based on modern spectral analysis, and inhibitory activities against plant pathogenic fungi were evaluated by studying the effects of different concentrations on the mycelial growth rate. Results Ergosta-5, 7, 22-trien-3beta-ol was isolated from Chaetomium cupreum ZJWCF079 for the first time. Antifungal activity assays showed that the compound had inhibitory activity to plant pathogenic fungi Sclerotinia selerotiorum and Botrytis cinerea with ECs0 values of 125μg/mL and 190 μg/mL respectively, but had no effects on Pythium uhimum, Rhizoctonia solani and Fusarium oxysporum. Conclusion Endophytic fungi from medicinal plants are promising sources of natural antifungal natural products.