三七根际土壤放线菌抗根腐病原菌活性次生代谢产物研究

Root-rot diseases, the disastrous soil-borne diseases, commonly occur in the cultivation of Panax notoginseng, and restrict the healthy and sustainable development seriously of the Panax notoginseng industry in Yunnan. Nowadays, the main control measure is application of chemical pesticides (especially fungicides), or most biological control researches are still at the stages of living bacteria preparation or crude extract of fermentation level. The active substances with the function of biological preventing and their antagonistic mechanisms are not clear yet. Actinomycetes are important producer of agricultural antibiotics, in this proposal, we intend to investigate the bioactive secondary metabolites of four actinomycete strains, isolated in situ from the rhizosphere soil of Panax notoginseng, which presented better antagonistic activities against root-rot diseases in our previous investigation, isolation and purification active components, elucidation and determination the structures of active compounds, assay the antagonistic activities against root rot diseases of interesting compounds in vitro. The aim of this proposal is to discover novel bioactive compounds against root rot diseases from microbial origin and elucidation the antagonistic mechanisms at the cell level, contributing to provide bioactive leading compounds for the development of high effective and low toxic green biological pesticides.

根腐病是三七种植过程中普遍发生的土传病害，严重制约着云南三七产业的健康持续发展。但目前主要施用化学农药（多为杀真菌剂）进行防治或生防研究大多数停留在活菌制剂或发酵液粗提物水平，具有生防功能的活性物质及作用机制尚未明确。放线菌是农用抗生素的重要产生菌，本项目拟对4株源自三七根际原位土壤，具有较好拮抗根腐病活性的放线菌开展其活性次生代谢产物研究，分离纯化活性成份；确定活性化合物结构；离体测定及验证化合物的拮抗根腐病活性；发现微生物源拮抗三七根腐病的活性新化合物并从细胞水平阐明其拮抗作用机制，为高效低毒绿色生物农药的创制提供活性先导新化合物。

根腐病是三七种植过程中普遍发生的土传病害，严重制约着云南三七产业的健康持续发展。放线菌是农用抗生素的重要产生菌，是寻找活性先导新化合物的重要资源。本项目对五株源自三七根际原位土壤，具有较好拮抗根腐病活性的放线菌开展了其活性次生代谢产物研究，运用现代色谱分离技术，从五株菌株发酵产物中共分离纯化出56个单体化合物；通过质谱、NMR及红外、紫外光谱数据确定了其中55个化合物的结构；以尖孢镰孢菌Fusarium oxysporum等5株三七根腐病病原真菌为指示菌，测定了化合物离体抗三七根腐病活性。通过项目实施，发现了对三七根腐病病原真菌具有中度抑制活性的微生物源新化合物，研究结果丰富了天然产物数据库的结构多样性，为后续新农药的研发及新天然产物的化学合成提供了活性先导新化合物。