Study On Chemical Constituents And Bioactivity Of Endophytic Fungi Isolated From The Pleioblastus Amarus And Taxus Chinensis Var.Mairei

Pleioblastus amarus belongs to Pleioblastus Nakai of the grass family, zhejiang province is rich in Pleioblastus amarus resource. In recent years, the research results show that the plant endophytic fungus can produce many kinds of bioactive substance, so it is a new microorganism resource which has latent value for exploitation. Taxus chinensis var.mairei belongs to the species of Taxaceae as well as Taxus genus, In recent years, the domestic many places in the large area introduction Taxus chinensis var.mairei, Taxus chinensis var.mairei, and3-7years of the Taxus chinensis var.mairei branches can replace the wild south yew bark extract as anticancer composition paclitaxel and10-Deacetylbaccatin Ⅲ materials. In this study, an endophytic fungi Xylaria sp.(LI) was first isolated from the fresh Pleioblastus amarus, next we get a lot of Xylaria sp.(LI) bacteria secondary metabolitesBy microbial fermentation method, and then focus on the chemical composition and biological activity of these secondary metabolites. In this paper the chemical composition and allelopathic activity of farmed Taxus chinensis var.mairei were studied,in order to provide a reference for how to use this medicinal resources in much smarter ways.All results are as follows:1. Research on chemical composition9compounds were obtained from the secondary metabolites of endophytic fungi isolated from the Pleioblastus amarus, the nine compounds are:(1) ergosterin,(2)(S)2hydroxy3phenylpropionic acid (3)(4E,8E)-N-D-2’-hydroxyoctadecanoyl-1-O-β-D-glycopyranosyl-9-methyl-4,8-sphingadienine,(4) butein,(5) Cerebroside A,(6) Methyl gallate,(7) gallic acid,(8) Vanillin,(9) stigmasterol. This9compounds were first isolated from the secondary metabolites of Xylaria sp.(LI).The RP-HPLC method established in this paper measures simultaneously the contents of taxol and10-Deacetylbaccatin Ⅲ of Taxus chinensis var.mairei in different harvesting time from China, and exploring the change of taxol and10-Deacetylbaccatin Ⅲ contents, in order to provide certain reference basis for the quality control of Taxus chinensis var.mairei.2. Research on biological activityThe antioxidant activity of five different extraction parts endophytic fungi isolated from the Pleioblastus amarus were determined by DPPH, the Antibacterial activity were determined by the method of slant, and the cytotoxicity were evaluated by lethiferous effect on brine shrimp. The result of the activity experiments showed that the five different extraction parts endophytic fungi isolated from the Pleioblastus amarus exhibited some capacity of antioxidation and Antibacterial activity,and week cytotoxicity.3. Research on allelopathyIn laboratory bioassays the Secondary metabolites of endophytic fungi isolated from the Pleioblastus amarus effected the seed germination and seedling growth of rape, radish, lettuce test species. Secondary metabolites showed double effects of concentration to radish and lettuce seed germination:lower concentration stimulate germination of seeding, higher concentration inhibit germination of seeding,and showed a neutral effect to rape seed germination; Significant inhibition in Root length, shoot height and fresh weight at high concentrations indicated the allelopathic activity of the secondary metabolites.The allelopathic effects of the aqueous extracts from Taxus chinensis var.mairei on seed germination and seedling growth of rape, radish, soybean, lettuce were studied by the methods of bioassay.the results suggests that rape, radish, soybean and lettuce are not suitable for intercropping with Taxus chinensis var.mairei, and hypothesizes that dicotyledonous crops are basically not suitable for intercropping with Taxus chinensis var.mairei.