Secondary Metabolities From A South China Seasponge And Two Actinomycetes And Their Antifungal Activities

Natural products are secondary metabolites of the natural organism that were preserved by natural selection in the evolution of millions of years.They have biological diversity,chemical structure diversity and various pharmacological properties.Many clinica drugs are directly or indirectly derived from natural products.Sponge and actinomycetes are important resources for drug discovery since they can produce a variety of secondary metabolites with diverse biological activities.In order to find the lead compounds,our research group has been devoted to the study of the bioactive secondary metabolites from marine sponges and microorganisms for many years.As part of our group’s bioactive compound discovery project,the chemical constituents of marine sponge Spongia pertusa Esper,actinomycetes Nocardia sp.LHW152404 and Streptomyces sp.31005 were studied in this work.A number of 46 compounds were obtained by chromatography techniques and two of them were new compounds.21 compounds(A1~A21)were isolated from the petroleum ether extract of the marine sponge Spongia pertusa Esper by chromatography methods including silica gel.,ODS,Sephadex LH-20,reversed phase HPLC.These compounds including 14 sesquiterpene quinones,4 steroids,3 bromo-derivative,1 polyketone were identified by IR,UV,1H-NMR,13C-NMR,COSY,HSQC,HMBC,NOESY,HRESIMS and ESIMS spectra.Among them,compound A1 is a new compound.Several compounds exhibited antifungal activities against Candida albicans,T.mentaqrophytes,T.rubrum with the MIC values of 12.5~50 μg/m L。12 compounds(B1~B12)were isolated from the fermentation products of Streptomyces sp.31005 by chromatography methods including solvent extraction,silica gel.,ODS,reversed phase HPLC.The structures of these compounds were identified by UV,1H-NMR,13C-NMR,COSY,HSQC,HMBC,NOESY,HRESIMS.Among them,compound B2 is a new compound.Compounds exhibited antifungal activities against Candida albicans,T.mentaqrophytes,T.rubrum with the MIC values of 6.25~50 μg/m L。13 compounds(C1~C13)were obtained from the fermentation products of Nocardia sp.LHW152404 by chromatography methods including solvent extraction,silica gel.,ODS,reversed phase HPLC.The structures of these compounds were identified by HRESIMS and NMR spectra.In this work,we described the isolation and structure elucidation of the secondary metabolites from marine sponge Spongia pertusa Esper,actinomycetes Nocardia sp.LHW152404 and Streptomyces sp.31005,the antifungal activities of the compounds were also reported.The results revealed that the biological and chemical diversity of the secondary metabolites from the marine sponge and the sponge associated actinomycetes,these diverse biological activity of secondary metabolites showed that great potential for pharmaceutical research and development.Our work accumulated new chemical scaffords for the discovery of bioactive natural products.What’s more,this study also revealed the chemical and biological activity diversity of the marine organism from the South China Sea,which was proved scientific basis for the further development and utilization of the rich marine resources in the South China Sea.