Research On The Secondary Metabolites From Two Endophytic Fungi

Microorganism features a short growth period, manageable metabolic process and has been investigated to produce lots of secondary metabolites with various types, novel structures, wide range of functions which can be industrialization by large-scale fermentation. This class of natrual products has become an important source of antibiotics, immunological regulators and anti-tumor agents including their lead compounds and attracts great attention from researchers in natural pharmaceutical chemistry.This thesis mainly focused on the research of the metabolites and their bioactivities of two fungi, Diaporthe sp. IFB-31p-10from the plant Rhizophora stylosa and Endothia sp. IFB-E023from the plant Vatica mangachapoi. From the fermentation of these two fungi,30compounds were isolated by the chromatography techniques including Si gel. CC., Sephadex LH-20and HPLC. The structures of11new and19known compounds were elucidated on the basis of spectral experiments such as IR, MS,1H-NMR,13C-NMR, HSQC, HMQC, HMBC, COSY, NOESY, CD and single-crystal X-ray diffraction analysis. The specific were described as follows:1. Diaporthe sp. IFB-31p-10was a fungus isolated from the healthy leaves of the plant Rhizophora stylosa. From the solid culture of the fungus,21compounds besides7polyketides,10sesquiterpenenoids,3glycolipids and1unsaturated acid were isolated and elucidated, in which there were11new compounds and3new natural products. Diaporine A (1) was demonstrated to be cytotoxic to human colorectal carcinoma SW1116, breast adenocarcinoma MCF-7, lung adenocarcinoma epithelial A549, nasopharyngeal carcinoma KB and gastric cancer SGC-7901cell lines with ICso values of4.40,4.93,9.31,9.14and11.79μM. Diaporine B (2) was cytotoxic to human colorectal carcinoma SW1116, breast adenocarcinoma MCF-7and nasopharyngeal carcinoma KB cell lines with ICso values of5.04,4.92,15.31μM. Isochromophilone X (16) exhibited moderate cytotoxic activities with its IC50values ranging from14.90-35.75μM. In primary identification of inhibitors of protein arginine N-methyltransferase1(PRMT1), compound2showed potent inhibitory activity.2. Endothia sp. IFB-E023was a fungus isolated from plant Vatica mangachapoi. From the solid culture of the fungus,9compounds were isolated and elucidated which contained4cytochalasins,2anthraquinones and3dimer-anthracenones.This thesis reported the main products of the ethanol extract of these two fungi and their bioactivities while the recent advances concerning metabolites of the mangrove-derived microorganisms were included.