Study On Secondary Metabolites Of Endophytic Fungi L99 And S108 From Dongxiang Wild Rice

Dongxiang wild rice(Oryza rufipogon Griff.)is the highest latitude wild rice found in Dongyuan Township,Dongxiang County,Jiangxi Province in 1978.It has excellent resistance properties with cold-resistance,drought tolerance,sorghum-resistance,insect-resistance and immune dwarf disease.The endophytic fungi L99 and S108,isolated from Dongxiang wild rice,was taken as the research object in this paper.Finally,strain L99 was identified as Sarocladium oryzae L99,and S108 was identified as Chaetomium globosum S108.The chemical compounds of ethyl acetate phase were obtained through the methods of lolid fermentation culture and extraction.Specific compounds were traced by separation methods such as silica gel column chromatography?Sephadex LH-20?TLC bioactivity tracing separation and high performance liquid chromatography.The structures of compounds were elucidated by means of spectroscopic techniques including high resolution mass spectrometry and nuclear magnetic resonance spectroscopy.At last,the effects of these compounds on the viability of human melanoma B16 cells were evaluated.The results are as follows:Deoxythymidine(1),2'-OMethyladenosine(2),2'-Deoxyuridine(3),uridine(4),adenosine(5),(E)-9-methyloctadec-9-enoic acid(6),ergosterol peroxide(7),helvolic acid(8),(9Z)-glycerin-1-monooleate(9)and dibutyl phthalate(10)were isolated from the strain L99.Dioctyl Phthalate(11),6-Hydroxymellein(12),Chaetomugilin D(13),Chaetomugilin S(14),Chaetoviridins A(15),Chaetoglobosins A(16)and6-O-demethyl-5-deoxyfusarubin(17)were isolated from the strain S108.In the experiment of inducing survival viability of B16 cells,compounds dibutyl phthalate(10)and 6-Hydroxymellein(12)were found to have a greater impact on the survival of melanoma B16 cells,and had the strongest killing effect on melanoma B16 cells at 10 ?M.