| Endophytic fungi are the source of a wide range of structurally interesting and biologically active compounds, which have been concerned by a number of areas such as medicines, plant pathology, microbiology and chemistry. As part of ongoing efforts to discover novel bioactive secondary metabolites from fungal sources in northwest, especially on the research and development of endophytes from medicinal plants,200 purified strains have been isolated from 30 species of plants and four insect tissues.Through analysis of high performance liquid chromatogram, TLC and activity screening of some strains crude extract,110001,112707,111806 strains were choosed as our target strains and their metabolites were studied.21 compounds have been obtained from the fermentation extracts by repeated column chromatography on silica gel, RP-18, and Sephadex LH-20, preparative HPLC and recrystallization. Structures of these compounds were elucidated on the basis of spectroscopic evidence including HR-ESI-MS, NMR and by comparison with literature reports. As a result,6 compounds, belong to ergosterol types, were isolated from the extract of 110001 strains (the first endophyte from Salvia przewahkii Maxim). Under the same fermentation, nine compounds, including two new solanapyrone analogues nor-solanapyrone A,B (Dsj-01, Dsj-02), and a new solanapyrone P (Dsj-04), were isolated from 112707 strains, which was isolated from fresh healthy stem of the same plant. The current study was carried out on the metabolites of 111806 strains, an endophytic fungus isolated from the Artemisia argyi growing in the region of northwest China. This led to the isolation of six compounds (ergostas).This dissertation focused on the fermentation condition, bioactivity evaluation of some crude extract obtained, isolation and structure elucidation of metabolites of endophytes. The chemical profiles of three endophytes were systematically investigated. And these results may be helpful to offer some references for the exploration and utilization of endophytes. |
