Study On The Secondary Metabolites Of One Soil Actinobacterial Strain And One Endophytic Fungus Strain

As one of the primary sources of natural products,microorganism has become the focus of natural product scientists because of its advantages such as easy cultivation,easy access,low cost and environmental protection.An extensive study showed that a plenty of the microorganisms in the soil had not been found and identified,the species of which are far more diverse than scientists can imagine.In addition,microorganisms from unique environments,such as rhizosphere microbiota of plants and endophytes of plants,are of great significance because of their long-term interaction with plants.Therefore,microorganisms are the cornucopias of natural products,and the research of natural products is still full of challenges and opportunities.In this dissertation,actinomycetes from rhizosphere soil of Artemisia lactiflora Wall.ex DC.and potato endophytes were selected as the research objects,and its secondary metabolites were separated and purified by silica gel column chromatography,gel chromatography,reversed-phase medium pressure chromatography and high-performance liquid chromatography.NMR,MS,X-ray single-crystal diffraction,circular dichroism,electron circular dichroism and JBCA method were used to identify the structures of the new compounds.The main results of this study are as follows:(1)Two hundred strains of actinomycetes were isolated and purified from the rhizosphere soil of Artemisia lactiflora Wall.ex DC.Some strains with good growth were selected for small fermentation and their metabolites were analyzed by HPLC.Two strains of actinomycetes sp.CD3-1 with abundant metabolites and high yield were selected.(2)Nine known compounds Actiphenol(1),dibutyl phthalate(2),benadrostin(3),cycloheximide(5),actiketal(6),cinnamamide(7),N-(2-(1H-indol-3-yl)ethylacetamide(8),benzoic acid(9),tyrosol(10)and a new amide compound,cycloheximide A(4)were isolated from actinomycete sp.CD3-1.(3)Nineteen known compounds including Ergosterol(11),aureonitol(12),linoleic acid(13),linoleic acid(14),(2S)-1-O-(7Z,10 Z,13Z-hexadecatrienoyl)-3-O-?-galactopyranosylglycerol(15),(2S)-1-O-(9Z,12Z-hexadecatrienoyl)-3-O-?-galactopyranosylglycerol(16),ethyl Orsellinate(17),methyl Orsellinate(18),Benzoic acid,2,4-dihydroxy-6-methyl-,2-phenylethyl ester(19),2,4-Benzenediol,1-methoxy-6-methyl(20),methyl Indol-3-ylacetate(21),orsellide B(22),orsellide A(23),(E)-1-(5-((E)-buta-1,3-dien-1-yl)-4-hydroxytetrahydrofuran-3-yl)pent-3-ene-1,2-diol(24),mollipilin F(25),Aureonitol A(26),Aureonitol B(27),latifolicinin A(28),harzialactone A(29),a new triphenyl derivative gliocladinins C(30),two new furanopolene derivatives chaetominin A(31),chaetominin B(32),a new C13-Polyketides chaetominin C(33)and a new orsellinic acid ester subaffineone A(34)were isolated from endophytic fungus Chaetomium subaffine L01.(4)The antitumor activity of some new compounds was evaluated by the MTT method,with human tumor cell lines Hep-2 and Hep G-2 selected as model.Finally,gliocladinins C(30)and chaetominin A(31)were found to inhibit the growth of two types of cancer cells.