三种植物中抗污损成分、构效关系及其环境降解研究

Most of marine antifouling agents which have beening currently used are toxic. These antifoulants obviously have influenced the development of marine economy and caused the damage of the ecological environment. This project expects to discover new environment-friendly natural antifouling agents with low toxicity from an abundance of plant resources in Yunnan so as to replace the toxic ones. It was discovered in study at present that the extracts of Piper betle, Uraria clarkei and Tinospora sagittata (Oliv.) Gagnep. var. yunnanensis showed strong anti-settlement activity against Balanus Amphitrite, with only a settlement rate of 0 %、31.3 ± 4.9 % and 37.8 ± 6.6 % at 50 μg/ml respectively..This project aims to: (1) isolate antifouling constituents from three medicinal plants using modern separation technology through bioassay-guided fractionation way and elucidate their structures on the basis of the spectroscopic analysis and chemical evidence; (2) evaluate the antifouling activities of natural products isolated, thus discover the active constituents of each plant and explore possible antifouling mechanism of bioactive compounds; (3) synthesize natural products with antifouling activity and their derivatives, evaluate their antifouling activities, study their structure-activity relationship using computer aided drug design method(CADD), then design and synthesize the targeted derivatives with stronger antifouling activity on the base of the results of CADD; (4) study the degradation of natural products with antifouling activity in environment and discuss their mechanism. This project can be expected to discover the antifouling constituents of these three medicinal plants, and obtain the lead compounds with potential value in application from these bioactive derivatives isolated and synthesized, which will lay the foundation for developing novel antifouling agents. This study is advantageous to not only the enlargement of the application field of plant resources in Yunnan, but also the protection of the marine eco-environment.

针对当前使用的海洋生物防污剂多为有毒防污剂，影响人类海洋经济活动和海洋生态平衡，本项目组希望从云南丰富的植物资源中发现活性好、毒性低的环境友好型天然防污剂，以替代有毒防污剂。前期研究发现蒌叶、野番豆及云南青牛胆3种植物药提取物在抑制纹藤壶幼虫附着实验中展示了明显的抑制活性。在浓度为50 μg/ml的3种提取物溶液中，纹藤壶幼虫附着率分别为0 %、31.3 ± 4.9 %及37.8 ± 6.6 %。本项目拟以生物活性为指导，采用现代分离技术，从上述3种植物中分离、鉴定抗污损活性成分；对所分离抗污损活性成分进行合成或结构修饰，结合计算机辅助药物设计(CADD)方法研究构效关系，初步探讨其抗污损作用机制；研究抗污损化合物的环境降解情况，探讨降解机理，为研发环境友好型抗污损制剂奠定前期研究基础。本项目的研究不仅有利于扩大云南植物资源的应用领域，而且对保护海洋生态环境有积极作用。

现有的海洋生物防污产品多为有毒防污剂，会对海洋生态环境产生不利影响。从天然产物中有望发现效用好、毒性低、易降解、环境友好的天然防污剂，以替代有毒防污剂。本项目以抑制纹藤壶幼虫附着实验为指导，采用现代分离技术，分离、鉴定蒌叶、野番豆及云南青牛胆3种植物药提取物中的活性成分，阐明其抗污损活性物质基础。对活性强的抗污损化合物进行构效关系研究，对优选的抗污损化合物开展环境降解测试与野外实验，初步探讨抗污损化合物的作用机制。通过项目的实施，从蒌叶、野番豆及云南青牛胆3种彝族植物药提取物的活性部位中分离、鉴定了101个化合物，完成了所分离化合物的抗污损活性测试，阐释了3种植物药中的主要抗污损物质基础。研究结果表明蒌叶中的主要抗污损成分为胡椒酰胺类化合物，野番豆中的主要抗污损成分为二氢异黄酮及黄烷类化合物，云南青牛胆中的主要抗污损成分为原小檗碱类化合物；对蒌叶中的胡椒酰胺类化合物及野番豆中的黄烷类化合物开展了构效关系研究，对两类化合物中的效用基团进行了分析。通过构效关系研究发现胡椒碱、胡椒油碱B、5,7-二甲氧基-4-羟基黄烷及7,3',4'-三甲氧基-5-羟基黄烷的抗污损活性尤其显著，对纹藤壶金星幼虫的半抑制附着浓度都小于1.5 µg/ml，比市面上的产品SeaNine 211 (2.3 ± 1.0 µg/ml)好；对胡椒酰胺类化合物及黄烷类化合物的合成工艺进行了探索与优化；胡椒酰胺类化合物的光解、水解实验表明该类化合物能在海水中降解，降解的主要途径之一是酰胺键的水解。上述研究结果及其初步的毒性评价、野外挂板实验表明来自蒌叶中的胡椒酰胺类化合物及野番豆中的黄烷类化合物活性好、毒性低、环境友好，具有良好的应用前景和深入研究的价值。项目还首次采用现代分离技术对蒌叶、野番豆及云南青牛胆3种彝族植物药的化学成分进行了系统的研究，有利于3种植物药在其他领域的开发应用。本项目的研究结果为三种植物药及其活性单体化合物在抗污损领域的应用奠定前期研究基础。