Isolation Of Endophytic Fungi From Five Plants, And Evaluation On MAO And AChE Inhibiting Activity Of Their Secondary Metabolites

Endophytic fungi and plants are a symbiotic relationship and Endophytic fungi in medicinal plants are very rich. The re ACh Es have shown that multiple biologically active substances such as anti-tumor, anti-bacterial were produced by Endophytic fungi of medicinal plants. This active substances can be used directly as active ingredients of the drugs or as lead compounds for drug development.To screen biologically active substances from plants, this paper focused on the isolation of endophytic fungi in five plants and their activities including anti- monoamine oxidase(anti-MAO) and anti-acetylcholinesterase(anti-ACh E) activities.Research contents and results are as follows:1.The isolation of endophytic fungi: 45 strains endophytic fungi were isolated by issueculture method from five plants.Among them 25 strains were isolated from Aconitum gymnandrum,4 strains were isolated from Aconitum tanguticum,5 strains were isolated from Aconitum sinomontanum,8 strains from were isolated Delphinium grandiflorum,3 strains were isolated from Corydalis edulis.2.Activity detection: 45 strains endophytic fungi were cultured and extracted by ethyl acetate and methyl alcohol and 90 extracts were obtained.The MAO inhibitory activity of 90 extracts were evaluated by 96-cell microplate method and results showed that 5 extracts showed remarkable MAO inhibiting activity with inhibitory rate more than 70%.The ethyl acetate extract of LRWT-39 were demonstrated to have the most high activity against MAO with IC50 values of 38.82μg?m L-1.The ACh E inhibitory activity of 90 extracts also were evaluated by Ellman’s method and results showed that they showed no activity.3.Preliminary research on chemical constitutent of six endophytic fungus:Seven compounds were isolated and purified from strain LRWT-26-1, LRWT-39, GWT-7, CQ-17, GWT-8 and HY-9 by using modern chromatographic methods, including silicagel co-lumn chromatography, preparative TLC,HPLC.Their structures were identified by1H-N MR, 13C-NMR, ESI-MS spectra.They were identified as Pseurotin A1(1), Alternaruol(2),Ergosterolperoxide(3),Bisdethiobis(methylthio)gliotoxin(4),alternariol methyl ether(5),Brevianamide F(6),fumitremorgin C(7). The MAO inhibitory activity of these compo-unds were evaluated by 96-cell microplate method and results showed that compound3 and compound 4 showed MAO inhibiting activity with IC50 values of 142μg?m L-1 and 130μg?m L-1 respectively. 4.Identification of five endophytic fungus:By using molecular biology methods,including analyzing the ITS r DNA assay of LRWT-39, GWT-7, GWT-8, LRWT-26-1 and CQ-17 and morphology, strain GWT-8, LRWT-26-1, LRWT-39 were identified as Alternaria sp., GWT-7 was identified as Rhinocladiella sp., CQ-17 was identified as Fusarium sp.