韧革菌中杀线虫倍半萜及其构效关系研究

Diseases caused by plant-parasitic nematodes have become the second largest disease in agricultural production. It is an important approach to obtain efficient environmental friendly biocontrol nematicide from novel metabolites isolated from microorganism.Sesquiterpenes had abundant structures and diversiform bioactivities.The fungi of Stereum could produce various sesquiterepenes according to previous studies.The nematicidal sesquiterepenes had been reported by proposer.In further study,five strong nematicidal Stereum strains obtained by nematicidal activity screening. On the basis of the preliminary work, the five strains will be studied on optimizing culture conditions,detecting components by LC-MS and TLC, isolating compounds by modern isolation methods and activity guidance,elucidating structures by spectral data, assaying nematicidal activity using nematodes Caenorhabditis elegans and Meloidogyne incognita,discussing the relationship of structures and activities based on the structural constitution, substitutional group and activity results, which will provide academic foundation for structural modification.The project will establish foundation to develop efficient environmental friendly nematicidal biocontrol pesticide.

植物线虫引起的病害已成为农业生产中的第二大类病害，从微生物资源中寻找新奇活性次生代谢产物是研发高效环保杀线虫生防制剂的重要途径之一。倍半萜是一类结构类型丰富,具多种生物活性的天然产物。研究表明,韧革菌属(Stereum)真菌能产生丰富的倍半萜类化合物，项目组前期首次报道了来源于该属真菌的杀线虫倍半萜。在此基础上，申请人以杀线虫活性模型对该属真菌进行筛选，获得5株对线虫具有强毒杀作用的菌株。本项目拟对筛选获得的活性菌株进行培养条件优化；基于LC-MS导向技术以及TLC检测成分，利用现代天然产物分离手段和活性追踪指导化合物的分离，通过波谱数据进行结构解析；以秀丽隐杆线虫和南方根结线虫为靶标，测定化合物的活性；在对一系列倍半萜类化合物结构单元、取代基团及活性结果分析基础上，探讨化合物与活性之间的构效关系，为进一步结构修饰提供理论指导。通过项目研究为开发高效新型环保杀线虫生物农药奠定基础。

通过本项目研究，从韧革菌属真菌中的亚大韧革菌（Stereum insigne），扁韧革菌（S. fasciatum），皱韧革菌（S. rugosum），层叠韧革菌（S. complicatum）和烟色韧革菌（S. gausapatum）5个种的菌株和3株未鉴定到种的共8株韧革菌中分离鉴定化合物70余个，包括20个新化合物。15个化合物具有生物活性。杀线虫活性结果表明，带醛基的倍半萜具有杀线虫活性，但活性的强弱还与其他取代基有关。本项目首次报道了亚大韧革菌（Stereum insigne），皱韧革菌（S. rugosum）和烟色韧革菌（S. gausapatum）三个种的次生代谢产物。该研究丰富了韧革菌属真菌的次生代谢产物，并为研发线虫生物防治制剂提供了新的资源和理论基础。通过项目研究，发表论文15篇，其中SCI收录论文13篇；申请3项国家发明专利，两项授权；培养毕业硕士生9名，在读博士2名。