海南药用红树木果楝内生真菌多样性及农用生物活性代谢产物研究

The secondary metabolites of marine microorganisms are an important source of high efficiency, low toxicity and environmental friendly for new pesticides leading compounds. In our preliminary study, endophytic fungi were isolated from the medicinal mangrove Xylocarpus granatum collected from Dongzhaigang. Two endophytic fungi HJ002 and HJ007 were selected as target strains by the bioactivity test, HPLC and LC-MS anlysis.16 compounds were isolated from the fungus HJ002, including fournoval indole diterpenoid alkaloids. This project aims to collect X. granatum from Dongzhaigang, Qinglangang and Yalong Bay, and to carry out the following work: (1) The resources bank of the endophytic fungi was established. (2) 3-6 target strains were determined, and leading by activity screening and LC-MS analysis the active secondary metabolites were isolated and identifited, and the structure-activity relationship were also explored. (3) The action mechanism of active compounds on cell membrane permeability and protein content cell proliferation were investigated. (4) The LC-MS datebase bank of the secondary metabolites was established. Based on these research, one or two lead compounds with high efficiency and low toxicity will be screened out, and lay the foundation for creating the independent intellectual property rights of new pestieides.

海洋微生物次级代谢产物为高效、低毒、环境友好的新型农药先导化合物的重要来源。本项目组已对海南东寨港的药用红树木果楝进行内生真菌分离，通过农业抗菌、杀虫活性、HPLC-DAD和LC-MS筛选，优选出2株目标菌株(HJ002和HJ007），并从HJ002中分离得到16个单体化合物，包括4个结构新颖的吲哚二萜类化合物。本项目拟采集海南三地（东寨港、清澜港、亚龙湾）的木果楝，开展如下工作：（1）建立海南木果楝内生真菌资源库；（2）筛选3-6株目标菌株，以活性与LC-MS为导向进行代谢产物分离、活性评价与构效关系研究；（3）从细胞膜通透性、蛋白质含量等角度，阐明抗菌作用机制；（4）建立木果楝内生真菌代谢产物LC-MS数据库。通过以上研究，有望优选出1-2个高效、低毒的药物候选分子，为研发具有自主知识产权的新型农药奠定基础。

海洋微生物次级代谢产物为高效、低毒、环境友好的新型绿色农药先导化合物的重要来源。本项目对采自海口东寨港、文昌清澜港和三亚亚龙湾的木果楝不同组织部位及其根际土壤的真菌进行系统的分离、种属鉴定、活性筛选和发酵培养，着重于对目标菌株发酵产物中的单体化合物进行抗农业致病菌的活性筛选工作，为新型生物农药的研发提供候选分子。本研究共鉴定 113 株真菌（包含 26 个属），构建了木果楝内生真菌的系统发育树，完善了药用红树木果楝内生真菌资源库。从中优选 5 株目标菌株，从目标菌株的发酵产物中分离鉴定了 163 个单体化合物，其中 32 个为新化合物，采用单晶衍射和 ECD 量化计算等辅助方法确定了部分化合物的绝对构型。通过抗农业致病菌、抗渔业致病菌、抗人类致病菌、抗虫、抗氧化、抗肿瘤和酶抑制剂等药理活性测试，发现活性化合物 51 个：其中 6 个化合物具有抗农业和渔业致病菌活性，5 个化合物具有抗虫活性，40 个化合物具有抗肿瘤、抗氧化和 α-葡萄糖苷酶抑制活性等生物活性，并对 1 个活性优良的化合物进行初步抗青枯雷尔氏菌作用机制研究。在Journal of Natural Products、Bioorganic Chemistry、Marine Drugs、有机化学等期刊发表研究论文 18 篇，授权国家发明专利 7 项，培养博士和硕士研究生共 5 名。本研究兼顾了海南药用红树资源的保护和开发利用，研究结果为新型生物农药和创新药物的研发提供了基础材料和理论支撑。