| The coelenterate sponges and corals belong to the lower marine invertebrate, being extensively distributed in marine ecosystems. They can emerge unique defensive substance in the term of struggling for existence which can be considered as the source of bioactive molecule including antimicrobe, antifouling, antitumor, adhere-inhibition and prey- resisting substance. So the sponges and corals resource are essential to modern drug development. The unique bilayer structure of outer and inner endosome and special strategy for sequestering food by filtering seawater make sponges and corals as ideal habitat for symbiotic microorganisms. For intance, they can contribute up to 50-60% of the sponge body volume in a high-microbial abundance sponge and microorganisms in seawater by 2-4 orders of magnitude even. Furthermore, these microbes are likely responsible for the production of molecules of interest previously ascrised to their host in many cases. Tough the research on metabolism of sponges and coral has made some important achievements, their development still is being restrict to deficiency of medicinal resource. Based the above fact scientists turned their eyes on the study of secondary metabolites from sponges and corals derived microorganism. In China, the south sea spans subtropical and tropical zone, which harbouring numerous and almost complete types of sponges and coral possessing valuable research resource. Thus this paper focus on the relevant study of the secondary metabolites of the microorganisms derived from sponges and coral growing in China South Sea.In order to obtain bioactive compound from coral and sponge derived microbe’s secondary metabolites, first we separated stains from the fifteen samples of corals and sponges which growed in Qi Lian-yu and YongXing Island of Hainan Provence. Adopting Dilution Methods for microorganisms especially the fungi and actinomycetes isolating, finally we obtained 115 fungi and 72 actinomycetes. The separated strains were fermentated in different ways to obtain the metabolites, and then pick out the stains which possess alkaloidal or halogenous characteristic coloration by the way of TLC coloration. Then the picked strains were analyzed by HPLC fingerprint to observe their ultraviolet absorption for gaining the stains possessing specific and series absorption. Subsequently we tested the activity ahout antimicrobial aspect and antitumor aspect to sceen the stains which having high activity. We employed an integrated method including the aspects above to determine one "talent stains" for target which will be fermentated to the further study on the secondary metabolite.According to the guide of the research way in the paper mentioned I got the fungi OUCMDZ-3658 to optimize the fermentation conditions including medium, pH, salinity and so on. After a growing period of about thirty-five days, I combined the whole broths then extracted them with ethyl acetate receiving ferment extracts. Then the extracts were subjected to extensive column chromatography and HPLC to give pure compounds. By means of modern spectral analysis (NMR, MS, CD, UV), the structures of fourteen compounds were determined, five of them were Quinazolinone alkaloids and three were Diketopiperazine alkaloids.The cytotoxic activity, inhibition activity against Glucosidase and antimicrobial activity of these compounds were evaluated. Compound 10 showed weak anti-fungus activity against Candida albicans and Compound 8,9,11 showed weak anti-bacteria activity Enterobacter aerogenes. Compound 5 showed weak cytotoxicity activity against K562 cells with IC50 value of 12.4 μM and Compound 3 showed weak cytotoxicity activity against MCF-7 cells. Compound 3,4 showed inhibition activity against Glucosidase with IC50 values of 为87.0 μM、114.9μM, affording the new structure-type for screening of α-glucosidase inhibitors. |
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