Studies Of Secondary Metabolites Of Two Species Of Plants And Two Species Of Fungi

Stellera chamaejasme L. is a toxic perennial herb widespread in northern and southwestern China. Its roots have been used in traditional Chinese medicine as emulgent and dermatological agents. Previous studies on the chemical constituents from the roots of this plant have identified diterpenoids, triterpene, biflavonoids, coumarins, lignans with antitumor, antimalarial and antibacterial activities.Strychnos nitida is a liana or scandent shrub. In our country, it is widely distributed in the Guangxi and Yunnan province, at altitudes of 200-1800 m. Its fruit has been used as a folk medicine for treating numbness of limbs and paralysis.Aspergillus niger belongs to the genus of Aspergillus (Moniliaceae). There is a vesicle spherical on its top, which is covered with a layer of stem base and a layer of small stems. Its wall is thickness and smooth. It is widely distributed in food and soil, and is generally recognized as a safe microorganism. It also has many of enzymes which have powerful biological activities, so it has been widely used for fermentation in industry.Cytospora chrysosperma, belonging to the genus of Cytospora (Sphaeropsicaceae), is a kind of important trees canker. The disease of which caused by the fungus Cytospora chrysosperma is one of the poplar diseases in North and Northeast China. So many scientists have paid much attention to treating that disease. Recently, many other groups isolated many new compounds which have novel structure skeletons and good biological activities from the genus of Cytospora.In order to further investigate the secondary metabolism of Stellera chamaejasme Linn., Strychnos nitida, Aspergillus niger and Cytospora chrysosperma, we studied on the chemical consituents of the 95% ethanol extracts which were extracted from the former two kind of plants and the fermentation liquids of the latter two species of fungi in this thesis.50 compounds were isolated from them by using normal separation methods and their structures were confirmed on the basis of spectroscopic data. Eighteen compounds were isolated from Stellera chamaejasme Linn., one of which was new compound. Fifteen compounds were isolated from Strychnos nitida, and two of which were new compounds. Eleven compounds were isolated from Aspergillus niger, seven of which were new compounds. And six known compounds were isolated from Cytospora chrysosperma.In the end of this thesis, one review was made on the systemic summarization for the chemical constituents and bioactivities of the genus Strychnos reported in the past ten years.The results would be a supplement for the research on bioactivity of chemical constituents as well as structure-activity relationship in traditional Chinese medicine, helpful reference for pharmacology, chemotaxonomy and sereening new medicines, and may benefit utilizing and developing the natural resources of our country.