Studies On The Secondary Metabolites From Cyanobacteria-derived Fungus Aspergillus Flavipes 164013

Ocean is a huge treasure trove of natural products.A large number of biologically active compounds have been isolated from marine organisms such as sponges,sea squirts,cyanobacteria and conch.Some marine-derived compounds have been successfully marketed as drugs.However,such a marine resource is limited,and with the further development of science and technology,it has been found that secondary metabolites in lower animals such as sponges and sea squirts are produced by their co-existing microorganisms.So in recent years,the number of compounds isolated from marine co-existing microorganisms experiences an increase,and secondary metabolites of fungal origin accounting for a large proportion.Isolation,purification and screening of target strains from the epiphytic fungi from the South China Sea.A total of 83 fungi were isolated and purified from sponge and cyanobacteria collected in the South China Sea.The species and genera of fungi were identified and classified by DNA amplification and gene sequence alignment analysis.Analytical methods such as HPLC and LC-MS were used to analyze the structural type richness,molecular weight and UV absorption of the compounds in the crude extract.Preference is given to strains with specific UV absorption,molecular weight range 400-1000 Daltons as target strains.Finally,the strain Aspergillus flavipes 164013 was selected,and make a futher reash on secondary metabolites of rice fertation of it.The fungus Aspergillus flavipes 164013 rice fermentation products were extracted by methanol permeation and extracted with ethyl acetate to obtain ethyl acetate layer extract.Separation and purification by atmospheric separation gel chromatography,silica gel chromatography,reversed phase chromatography,and high-pressure liquid chromatography methods,a total of 19 compounds were obtained.Identification of planar and relative configurations of compounds by NMR,ultraviolet,infrared and circular dichroism spectroscopy.Finally,19 compounds were identified,including 4 new skeleton compounds,6 chlorodiphenyl ethers,1 benzophenone,2 cyclopeptides,1 quinone and 5 alkaloids.Through screening of anti-bacterial,anti-tumor and myocardial cell protection models,it was found that new skeleton compounds A1 and A2 had protective effects on rat cardiomyocyte H9c2 at safe concentration of 10 ?mol/L.In summary,through systematic study on the secondary metabolites of A.flavipes 164013 rice fermentation,four new skeleton compounds were isolated and five alkaloids were isolated from the genus for the first time,which enrich the chemical varieties of Aspergillus flavipes.Meanwhile,new skeleton compounds A1 and A2 have myocardial protective activity.Provide new drug templates,material basis and scientific basis for the development of innovative drugs for myocardial protection.