薇甘菊化学成分对六种核桃病原真菌的抑菌活性

Antifungal activity of chemical constituents from Mikania micrantha against 6 species of Juglans regia pathogenic fungi

为探究入侵植物薇甘菊(Mikania micrantha H.B.K)化学成分的抑菌作用,采用硅胶柱层析、Sephadex LH-20凝胶柱层析色谱法,从薇甘菊地上部分乙酸乙酯萃取物中分离得到5个化合物,根据1H NMR、13C NMR、MS波谱数据,分别鉴定为豆甾醇(1)、薇甘菊内酯(2)、去氧薇甘菊内酯(3)、异泽兰素(4)和泽兰黄酮(5)。采用平皿法测定了薇甘菊甲醇提取物、不同溶剂萃取物及分离得到的化合物对6种核桃病原真菌菌丝生长的抑制活性。结果表明,薇甘菊乙酸乙酯萃取物对炭疽菌、正丁醇萃取物对叶点霉的菌丝生长有较强的抑制作用,EC50分别为1.25000 mg/mL和1.66000 mg/mL;化合物2和化合物3对拟茎点霉和壳梭孢菌丝生长抑制率均显著高于其他化合物,化合物2和化合物3对拟茎点霉的EC50分别为60.62μg/mL和89.13μg/mL,对壳梭孢的EC50分别为43.65μg/mL和61.66μg/mL。

In order to explore the antifungal effects of the chemical constituents of invasive Mikania micrantha,five compounds were isolated from the ethyl acetate extract of the aerial part of Mikania micrantha by chromatographic methods such as silica gel column chromatography and Sephadex LH-20 gel column chromatography.According to their 1H NMR,13C NMR and MS spectral data,the five isolated compounds were identified as Stigmasterol(1),Mikanolide(2),Deoxymikanolide(3),3,5,4′-trihydroxy-6,7-dimethoxy-flavone(4)and Nepetin(5),respectively.The antifungal activities of different solvent extracts and isolated compounds from Mikania micrantha against 6 species of pathogenic fungi of walnut were determined by the petri plate method.The results showed that the ethyl acetate extract and the n-butanol extract had a high inhibitory effect on the mycelia growth of Colletotrichum sp.and Phyllosticta sp.,with EC50 of 1.25000 mg/mL and 1.66000 mg/mL,respectively.Compounds 2 and 3 showed higher inhibition rats against Phompsis sp.and Fusicoccum sp.than other compounds.The EC50 of compounds 2 and 3 against Phompsis sp.were 60.62μg/mL and 89.13μg/mL,and against Fusicoccum sp.were 43.65μg/mL and 61.66μg/mL,respectively.