Bio-screening And Bio-induction Of Actinomycete Associated With Marine Sponge Hymeniacidon Perleve

Marine sponges harbor large amounts of diverse bacteria and some evidence shows that sponge associated bacteria are at least involved in the biosynthesis of some sponge derived natural products or are in fact the true sources of them. In this thesis, the bacteria associated with marine sponge Hymeniacidon perleve was investigated. Three parts of this work are as following: bioactive metabolites extraction from screened active actinomycetes,, bioactive induction study of sponge associated bacteria and the diversity of sponge endocellular bacterial community.Antimicrobial bioassay and antitumor bioassay were carried out to screen the bioactivities of actinomycets from marine sponge Hymeniacidon perleve. Strain stability and polarity of bioactive compounds were investigated to deal with 5 strains with good antimicrobial activity. .And strain Hp-109 was selected as target strain depending on it's good antibacterial activity, good stability and polarity.Fermentation conditions for strain Hp-109 to produce antibacterial compounds were optimized and under the optimal condition Hp-109 was fermented in a large scale. After repeatedly extraction, silica column chromatography separation, size-exclusion column separation and Preparative High Performance Liquid Chromatography separation, bioactive compound S was obtained. By structural elucidation, S was proved to be the mixture of two homologues, which might be new compounds because no similar compounds can be found from the Antibase database of metabolites by microorganisms. Further structural identification is being carried on.In order to get more bioactive compounds from sponge associated bacteria, co-culture induction was introduced as a novel tool to exploit sponge-associated bacteria for antibiotics discovery. Experimental results indicated that chemical...