| Endophytic fungus is a special kind of microorganism,which widely exists in healthy plant tissues.Their various secondary metabolites are one of the important sources of novel chemical skeleton compounds.An investigation on the secondary metabolites of microorganisms from unusual or special media can increase the chances of discovering novel structures and bioactive chemical constituents.The well-known anticancer drugs camptothecin and hydroxycamptothecin are the secondary metabolites of Camptotheca acuminate Decne,and it has been reported that the endophytic fungi isolated and purified from Camptotheca acuminata can produce 10-hydroxycamptothecin.Therefore,we isolated endophytic fungi from Camptotheca acuminata and studied their metabolites,which will lead to discover the endophytic fungi which can produce novel compounds with good biological activities.Based on novel chemical structure and biological activity-oriented,the present research was focused on active ethyl acetate fractions of two endophytic fungi and one medicinal plant.The structures of compounds were identified and the pharmacological activities of the monomeric compounds were tested by various chromatographic separation technologies.The aim is to find natural products with novel structure and good biological activity.Finally,seventy one compounds were isolated and identified.These compounds are structurally diverse,including sterols,terpenes,butenolides,furanones,naphthoquinones,macrocyclic peptides,quaternary cyclic lactones,cerebroside,isoflavones,matrine alkaloids,and quinolinidine alkaloids,of which eight compounds were new.In addition,antidiabetic and anticancer activities of some monomeric compounds were screened.A group of adelomycete Cladosporium cladosporioides(XS2)was a type of mold that produces conidia.It was often found on live or dead crops.Some of them parasite in crops and even make them sick.Mycospores were widely distributed and abundant in the outdoor air.Indoors,they can grow on the surface of appliances when moisture was too heavy.Nineteen compounds were isolated from the ethyl acetate fraction of Cladosporium cladosporioides in rice solid culture medium(XS2-EtOAc).The compounds were identified as: ergosterol(1),24-Methyl-25-homocholesterol(2),terretonin(3),terretonin A(4),terretonin C(5),terretonin B(6),3-hydroxy-4-(4-hydroxyphenyl)-5-[(4-hydroxyphenyl)methyl]-2(5H)-furanone(7),butyrolactone II(8),2-furancarboxylic acid,2,5-dihydro-4-hydroxy-3-(4-hydroxyphenyl)-5-oxo-2-(phenylmethyl)-methyl ester(9),butyrolactone I(10),butyrolactone V(11),aspernolide A(12),lovastatin(13),(1α,2α,4α)-4-(1E)-1-propen-1,2-Cyclopentanediol(14),hexadecan-1-ol(15),aspterpenacids A(16),(3R,4R)-6,7-dimethoxy-4-hydroxymellein(17),aspulvinone K-CR(18)and aspulvinone F(19).Compound 12 showed good activity against laryngeal carcinoma Hep-2 cells.Twenty-five compounds were isolated from the ethyl acetate fraction of Penicillium polonicum(XS3-EtOAc).Among them,7 compounds were new and dentified by 1D,2D NMR and MS as fusarubin(20),fusarubin methyl ether(21),javanicin(22),anhydrofusarubin(23),2-isopropanol-3-methyl-7-methoxy-naphthazarin(24),3,5-hydroxydihydrofusarubin D(25),neovasinin(26),walterolactone B(27),3,6-Dimethyl-4-hydroxy-2H-pyran-2-one(28),5,6-Dihydro-4-methyl-2H-pyran-2-one(29),4,5-dimethyl-2-(1-methylpropyl)-3-furancarboxylic acid(30),apocynin(31),(S)-2-amino-4-methyl-N-((R)-1-(methylamino)-1-oxopropan-2-yl)pentanamide(32),1233 A(33),polonicin A(34),tridecyl(E)-octadec-9-enoate(35),chrysogesides B(36),polonicin G(37),polonicin B(38),cyclosporine A(39),cyclosporine E(40),polonicin C(41),polonicin D(42),polonicin E(43)and polonicin F(44).Nine compounds(21-25,33,34,38)were screened with a GLUT4 translocation assay,and the results showed that compounds 33,34,38 exhibited good effects on GLUT4 translocation by 1.35-1.80 folds,of which the most active compound polonicin A(34)enhanced GLUT4 translocation by 1.80 fold.Then the dose-effect relationship experiment was carried out on compound 34,and it was found to be highly active at a concentration of 30 μg/mL.Totally,27 compounds were isolated from The acidic ethyl acetate fraction,the alkaline ethyl acetate fraction and the petroleum ether fraction of Sophora davidii(Franch)Skeels.Eight compounds were isolated from petroleum ether,including 6 flavonoids,of which compound 45 was a new compound and identified as leachianone H,and other known compounds were identified as leachianone A(46),leachianone B(47),exiguachromone A(48),maackiain(49),pterostilbene(50),acacetin(51),apigenin(52).Sixteen compounds were isolated from acidic ethyl acetate fraction,including twelve isoflavones.The remaining known compounds were identified as medicagol(53),resveratrol(54),isoformononetin(55),pseudobaptigenin(56),3’-methoxydaidzein(57),3’,4’-dimethoxy-7-hydroxyisoflavone(58),pratensein(59),biochanin A(60),calycosin(61),genistein(62),4’,5,7-trihydroxy-6-methylisoflavone(63),glycyrrhizin(64),pinosylvine(65),7,5’-dihydroxy-3’-methoxyisoflavone(66),7,4’-dihydroxy-3’,5’-dimethoxy isoflavone(67),5,7,2-trihydroxy-4-methoxyisoflavone(68).Two matrine alkaloids were isolated and purified from alkaloids and identified as sophocarpine(69)and oxysophocarpine(71).A quinolinisidine alkaloid was identified as(-)-N-methyl genistein(70). |
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