Extraction And Isolation Of Bioactive Lipophilic Constituents From Salt-tolerant Jerusalem Artichoke And Its Endophytic Fungi

Jerusalem artichoke(Helianthus tuberosus), also called devilsginger or ginger, is a perennial herbaceous plant belonging to the Helianthus genus, Asteraceae family, and it is widely applied in ecology, food, energy, chemistry etc. Although Jerusalem artichoke contains a series of terpenes and steroids, but the application of them has been rarely reported. There is also no report about the secondary metabolites of endophytic fungi in Jerusalem artichoke as far as we know. In this paper, we studied the extraction and isolation of terpenoids and steroids from leaves and tubers of Jerusalem artichoke grown in salinized lands, and an endophytic fungus of Jerusalem artichoke was also chemically investigated.Lipophilic constituents were extracted from the leaves and tubers of Jerusalem artichoke, and the isolation of β-sitosterol and stigmasterol was designed and optimized. β-Sitosterol and stigmasterol were isolated by solvent extraction, column chromatography on silica gel and Sephadex LH-20, and preparative high performance liquid chromatography. The purity of β-sitosterol and stigmasterol was determined by high performance liquid chromatography. Both compounds reached a purity of more than 90%. The concentration conditions of terpenoids by solvent extraction, column chromatography on silica gel and Sephadex LH-20 were designed and optimized, and the contents of total terpenoids were determined by UV spectrophotometric method. Concentration of terpenoids has reached more than 30%, and bioassay results showed that the concentrating terpenoids have certain insecticidal activity.One endophytic fungus was selected by bioassay screening and then fermentated. 7 compounds were isolated from the fermentation extracts by column chromatography on silica gel and Sephadex LH-20, preparative thin layer chromatography and high performance liquid chromatography. The structures of these compounds were elucidated by spectroscopic methods, such as 1H NMR、13C NMR and DEPT.The research increases the development, utilization as well as added value of salt tolerance Jerusalem artichoke, and makes the development and utilization of Jerusalem artichoke more refined. Study the endophytic fungi derived from Jerusalem artichoke tubers explore new utilization of Jerusalem artichoke from the angle of natural product chemistry.