红豆杉内生真菌Trichoderma sp.次生代谢产物及其抗菌活性研究

Secondary metabolites and their antimicrobial activities from endophytic fungus Trichoderma sp.isolated from Taxus wallichiana var.chinensis(Pilg.)Florin

目的从红豆杉内生木霉属真菌MPT-009的次生代谢产物中发现具有抗菌活性的单体化合物。方法采用硅胶、ODS、Sephadex-LH20柱层析和半制备高效液相等方法进行分离,利用高分辨率质谱、NMR波谱数据和电子圆二色谱(ECD)计算等方法确定化合物结构,通过二倍稀释法评价化合物对8种临床耐药性细菌和7种植物病原真菌的抗菌活性。结果从木霉属真菌MPT-009大米发酵产物中共分离得到了一个新的聚酮化合物trichoketide F(1)和6个已知化合物10-deacetylkoningiopisin D(2)、koninginin A(3)、koninginin B(4)、koninginin D(5)、koninginin E(6)、isoharziandione(7)。化合物1对马铃薯黄萎病菌、水稻纹枯病菌、油菜菌核菌、棉花枯萎病菌、草莓黑斑病菌、玉米小斑病菌显示一定的抑制活性,MIC值为12.5~50μg/mL。结论本文对红豆杉内生真菌Trichoderma sp.的次生代谢产物进行了深入研究,分离得到1个新化合物,丰富了木霉属真菌代谢产物,且该化合物对油菜菌核病菌具有较好的抑制活性,MIC值为12.5μg/mL。

Objective To find monomer compounds with antimicrobial activity from the secondary metabolites of the endophytic fungus Trichoderma sp.MPT-009 isolated from Taxus wallichiana var.Chinensis(Pilg.)Florin.Methods Separation is carried out by silica gel,ODS,Sephadex-LH20 column chromatography,and semi-preparative HPLC.The structures were determined by high-resolution mass spectrometry,NMR spectral data,and electron circular discography(ECD)calculation.The antimicrobial activities against eight clinically resistant bacteria and seven plant pathogenic fungi of isolated compounds were evaluated by the double dilution method.Results A new polyketone compound trichoketide F(1),together with six known compounds,10-deacetylkoningiopisin D(2),koninginin A(3),koninginin B(4),koninginin D(5),koninginin E(6)and isoharziandione(7)were isolated from the rice fermentation product of the endophytic fungus Trichoderma sp MPT-009.Compound 1 showed certain inhibitory activity against Verticillium dahliae Kleb,Rhizoctonia solani,Fusarium oxysporumf.sp.vasinfectum,Sclerotinia sclerotiorum,Alternaria fragriae,and Helminthosporium maydis with MIC values of 12.5~50μg/mL.Conclusion In this paper,we investigated the secondary metabolites and their antimicrobial activities from Trichoderma sp.,resulting in the isolation of a new polyketone that enriched the metabolites of Trichoderma sp.Furthermore,compound 1 exhibited moderate inhibitory activity against Sclerotinia sclerotiorum with a MIC value of 12.5μg/mL.