南海海绵共生真菌的原位培养分离及其新活性物质发现

Sponges-associated fungi are the resource treasures of drug lead, because they can produce novel biologically active secondary metabolites. Huge resources of “uncultivable” fungi as new potential sources of new bioactive compounds from sponges have not been studied. In situ cultivation is the key to obtain sponge “uncultivable” symbiotic fungi. Recently, based on the modified in situ cultivation technique, 25 fungal strains been obtained from a marine sponge in the South China Sea by applicant, including two suspected new species. Among them, applicant got three strains, which can produce new bioactive compounds. Examination of the chemical constituents from one of three stains has led to the isolation of six new bioactive compounds. . Based on the above results, An optimized in situ microbial cultivation technique will be continually applied to fully acquire “uncultivable” fungi resources from the marine sponge in this project. The targeted strains are selected by integrating molecular networking and biological assays. And the chemical constituents on the targeted strains will been systematically investigated by fermentation optimization, chromatographic separation and spectral identification techniques combining a bidirectional trace including molecular networking and biological activity evaluation, trying to find a lot of new bioactive compounds. This project would not only numbers of compounds with novel structures and pharmacological properties will be discovered, which will provide a new object for further new drug study, but also provide scientific basis for the sustainable in-depth utilization of sponge resources.

海绵共生真菌能产生结构新颖、活性显著的次级代谢产物，是药物先导化合物的资源宝库。海绵蕴藏着丰富的尚未被研究的“未培养”真菌资源，是潜在活性物质的新来源。原位培养技术是获得海绵“未培养”真菌的关键。申请人前期通过设计改良原位培养装置，从一种南海海绵中分离获得25株真菌，其中包括2个疑似新种，以及优选了3株产新颖活性物质的目标菌株。对其中的1株菌株的化学成分进行了初步的研究，发现了6个新活性物质。. 本项目拟在前期工作基础上，继续优化海绵微生物原位培养技术，充分挖掘该海绵“未培养”真菌资源；利用分子网络技术与生物活性集成筛选，优选目标菌株；通过发酵优化、色谱分离和波谱鉴定等技术，结合分子网络技术与活性评价对新活性成分进行双向追踪分离，发现一批结构新颖的活性先导化合物。本项目的实施不仅将为新药研究提供新对象，还将为海绵生物资源的可持续深度挖掘利用提供科学依据。

海绵共生微生物已成为海洋药物研究的热点对象。目前国内对海绵“未培养”共生微生物方面的活性先导化合物研究还未曾报道。本项目以I-tip方法对南海海绵共生真菌进行原位培养，共分离鉴定68株原位培养真菌。对其中4株优选的菌株Fusarium sp. LS68、Penicillium sp. LS54、Aspergillus sp. HLM45、和Aspergillus sp. LS34进行发酵条件优化、大规模发酵和活性次级代谢产物的研究。结合LC/MS/MS分子网络技术和生物活性集成为导向，综合运用多种天然产物化学分离分析技术，深入挖掘海绵共生真菌新颖次级代谢产物。综合运用现代波谱学手段，结合圆二色谱法、Mosher法、量子化学计算ECD等立体构型确定方法，确定化合物的结构。本项目共分离鉴定60个化合物，其中新化合物20个，10个化合物具有一定程度的生物活性。本项目的实施不仅为将来进一步应用研究提供新的药用微生物资源和活性先导化合物，而且为开发出具有我国自主知识产权的海洋创新药物奠定基础，极大的促进了海洋药物的开发。另外，在本项目资助下，以第一作者或通讯作者发表论文12篇，其中SCI论文10篇，授权发明专利2件