Study On The Secondary Metabolites From Two Endophytic Fungi

Background: Screening bioactive ingredients from natural products is one of the effective ways to develop new drugs,but the probability of finding active compounds from medicinal plants has been decreasing.Plant endophytic fungi may produce similar active compounds with host plants,and a wide variety,with great potential for development.Therefore,from the plant endophytic fungi metabolites to find active compounds is an effective way to develop new drugs from the perspective of sustainable development.Some previous work has demonstrated that Rabdosia rubescens‘s endophytic fungi could produce cytotoxic polyketides,tetramic acids,antiviral isoindolones,indoletriterpenoids,sequesterpenoids,and flavonoids.Rabdosia rubescens,also known as(Rabdosia rubescens)in TCM,is commonly used in Chinese folk medicine to treat stomach aches,pharyngitis,sore throats,coughs and wrestling injuries.This herb has increasingly gained attention because of its use as an antitumor herb and because of the antitumor activities of its discovered bioactive constituents.The herb contains a variety of active components,including diterpenoids,flavonoids,phenolic acids,triterpenoids and volatile oils.Among these compounds,the diterpenoid compound oridonin was reported to possess inhibitory effects on a variety of cancer cell lines,such as leukemia,colorectal cancer,esophageal cancer,liver cancer,epidermoid carcinoma,lung cancer and uterine cervical cancer.We wondered to study whether endophytic microorganisms of this plant could produce similar metabolites of plant Rabdosia rubescens.We are going to Henan province Rabdosia rubescens as the research object,the endophytic fungi were Chaetomium globosum to the separation and purification.Reports of the literature for Chaetomium globosum from stimulates in isolating compounds has amounted to more than 200,with varying degrees of anti-cancer,anti-bacterial activity.In our present study is therefore conducted to investigate the chemical constituents of endophytic fungus isolated from mangrove,and Penicillium expansum is associated from mangrove,we report the isolation pureculture of endophyti fungi,fermentation,extraction,purification,structure elucidationand biological assay of isolated compounds.Purpose:The secondary metabolites of Expanded penicillium and Chaetomium globosum were respectively studied in this paper by means of chemical composition analysisin order to get monomer compounds of new structure withbetter anticancer activity and antibacterial activity.This will be of great significance for the discovery of compounds of good biological activity and the research of endophytic fungi.Method: The solid and liquid fermentation were used for fermentation of Expanded penicillium and Chaetomium globosum in this paper.Normal phase silica gel column,MIC,macroporous adsorption resin,HPLC and Sephadex LH-20 methods were used forthe separation and purification of chemical constituents from secondary metabolites.IR,UV,NMR,13C-NMR technology were used to identify isolated monomers and confirm their structures.Then MTT assaywas used todetermine the antitumor activityof separated compounds and papers disc,doubling dilution method,AGAR dilution method for the study of antibacterial activity.Conclusion:(1)We have seprated 16 endophytic fungi from Rabdosia rubescens,the activity of the cancer cells with coarse extraction test,5,9,11 and 15 fungi have different degree of anti-cancer role;(2)We have seprated ten monomer compound from the secondary metabolites of Rabdosia rubescens,the compound were identified as: stigmasta-4,6,8(14),22-tetraen-3-one(1),4-methyl-5,6-dihydro-2H-pyran-2-one(2),(E)-6-hydroxy-4,6-dimethyl-3-heptene-2-one(3),glyceroyl monopaimitate(4),deoxycytidine(5),4-hydroxyl-2-Deoxyuridine(6),3?-hydroxy-5?,8?-epidioxyergosta-6,22-dienes(7),bungein A(8),?-sitosterol(9),?ditutyl phthalate(10).(3)We have seprated ten monomer compound from the secondary metabolites of Penicillium expansum,the compound were identified as: erg-osterolperoxide(11),cyclo-(Gly-L-Pro)(12),anthraquinone aversin(13),5-methoxysterigmatocystin(14),6,8-di-O-methyl averufin(15),cyclo(Gly-D-Phe)(16),cyclo(L-4-Hyp-D-Phe)(17),Brevianamide K(18),brevianamides Q(19),Brevianamides W(20).(4)Separated from the extended penicillium Brevianamide Q,5-methoxysterig matocystin monomer compounds have certain anti-cancer effect.