草珊瑚内生真菌SgG4抗植物病原真菌的活性物质研究

Study on the Active Substances of Endophytic Fungus SgG4 from Sarcandra glabra Against Plant Pathogenic Fungi

对草珊瑚内生真菌卷曲木霉Trichoderma spirale SgG4抗植物病原真菌的活性物质进行研究。采用菌丝生长速率法对SgG4发酵产物进行抑菌活性测定,采用硅胶柱层析法并结合活性追踪对发酵产物的活性萃取物进行活性物质分离纯化,运用核磁共振谱和质谱技术对活性化合物进行结构鉴定。结果表明,抗菌活性物质主要存在于发酵产物的乙酸乙酯萃取物中,该萃取物对13种植物病原真菌均有较好的抑制活性,EC 50值为0.0002~2.4757 g/L,其中对甘蔗凤梨病菌的抑制活性最好。从发酵产物的乙酸乙酯萃取物中分离出1个抑菌活性化合物,鉴定为木霉酸(trichoderma acid)。木霉酸在0.1 g/L时,对13种植物病原真菌均有抑制作用,其中对茶轮斑病菌、烟草黑胫病菌、甘蔗凤梨病菌和白绢病菌的抑菌率为100%,对其余9种植物病原真菌的抑菌率为21.43%~85.71%。可见,木霉酸的抑菌活性较好且抗菌谱广,在微生物源杀菌剂方面具有较好的开发应用前景。

The antifungal activity of Trichoderma spirale strain SgG4 from Sarcandra glabra against plant pathogenic fungi was studied.Theantifungal activity of SgG4 fermentation products was determined by mycelial growth rate method.The active extract of the fermentation product was separated and purified by silica gel column chromatography combined with activity tracing.The structure of the active compound was identified by nuclear magnetic resonance spectrum and mass spectrometry.The result showed that the antifungal active substance mainly existed in the ethyl acetate extract of fermentation product,which had good inhibitory activity against 13 plant pathogenic fungi,with EC 50 values ranging from 0.0002 to 2.4757 g/L,among which the inhibitory activity against Ceratocystis paradoxa was the best.An antifungal compound was isolated from the ethyl acetate extract of the fermentation product and identified as Trichoderma acid.At the mass concentration of 0.1 g/L,Trichoderma acid had inhibitory effects on 13 plant pathogenic fungi,among which,the inhibitory rate against Pestalotiopsis theae,Phytophthora parasitica,Ceratocystis paradoxa and Athelia rolfsii was 100%,and the inhibitory rate against the other 9 plant pathogenic fungi is 21.43%-85.71%.It can be seen that Trichoderma acid has good antifungal activity and wide antifungal spectrum,and has a good development and application prospect in microbial source fungicides.