Studies On The Secondary Metabolites Of Aspergillus Terreus OUCMDZ-1925from Yellow River Delta

The biological species of marine resources are rich accounting for more than80percents of the Earth’s. The special marine ecological environment with high salinity,high-pressure, low temperature, oligotrophic and so on, makes a high degree ofbiodiversity of secondary metabolites of the marine species. So the research anddevelopment of marine resources have been become the foucus of most people’sattention. According to statistics, more than50percents compounds among the20,000kinds new compounds isolated from marine organisms have the biologically active ofantitumor, antibacterial, antiviral, and anti-inflammatory in worldwide.Mangrove is the woody plant community that located in coastal intertidal zone oftropical and subtropical. Yellow River Delta is located in convergence zone betweenlake and ocean. These special ecological environments provide a wealth of species tofind valuable marine microorganisms. In recent years, finding natural products with awide range of biological activity from marine microorganisms are also increasinglysubject to international attention. We obtained109microbial strains, including42fungal strains,55actinomycete strains and12bacterial strains from the samples ofmangrove soil from Wenchang in Hainan, from the gorgonians and sponges fromWeizhou and from the zone of Dongying Yellow River. And their chemo-diversity andcytotoxicity were studied by integrated TLC, HPLC and bioassay methods. StrainOUCMDZ-1925was selected for further study.The target microbial strain OUCMDZ-1925was identified Aspergillus terreus bythe sequences of18sRNA and ITS. The fermentation broth of A. terreus OUCMDZ-1925was successively extracted with ethyl acetate (EtOAc). From the EtOAc extracts,twenteen compounds were isolated by repeated column chromatography on silica gel,Sephadex LH-20and RP-18, followed by reverse-phase semi-preparative HPLC andrecrystallization. By means of spectroscopic method such as MS,1D-NMR and2D-NMR, and their physicochemical properties, nine compounds had been identified. Seven compounds are3-phenyl-4-benzyl-γ-butyrolactone derivatives, another twocomounds are ergosterol and methyl2,4-dihydroxy-3,5,6-trimethylbenzoate. Amongthe compounds, compounds1and2which we named as Z-alkelactone A andZ-alkelactone B were two novel compounds and the others were known compunds.The known compounds were (+)-butyrolactone I (3), butyrolactone II (4),butyrolactone III (5), butyrolactone IV (6), aspernolides A (7), methyl2,4-dihydroxy-3,5,6-trimethyl benzoate (8) and ergosterol (9).