Secondary Metabolites From Sponge Pseudoceratina Sp.and The Associated Actinomycetes

With the increase of bacterial drug resistance,the development of antibiotics with new structures has become a major trend in natural product research.In particular,the discovery of new compounds with excellent biological activity from marine organism a new way for the development of antibiotics.The chemical constituents of marine invertebrates Pseudoceratina sp.and its three co-epiphytic actinomycetes Streptomyces parvulus 52-5,Streptomyces sp.92-10 and Streptomyces sp.94-4.were systematically studied.During the experiment,28 compounds were isolated from the ethyl acetate extract of the above sponges and the fermentation broth of three kinds of acinomyces by using various separation and purification techniques,such as Column chromatography,Octadecylsilyl Silica,Sephadex LH-20 gel column chromatography,Hight performance liquid chromatography,etc.The structures of these 28 compounds were identified by NMR,HR-MS,IR,UV and other modern spectral analysis techniques.It contains 2 alkaloids,3 polyketide,4 steroids,5 macrolides,6 amino acids,and including 6 new compounds,(2 terpenoids,3 macrolides,and 1 carboxylic acid).Seven compounds,two alkaloids,one polyketide and four steroids were obtained from the sponge of Pseudoceratina sp.,and identified as: aerothionin(1),homoaerothionin(2),6-desmethyl-6-ethylspongosoritin A(3),(22E,24R)-5?,8?-epidioxy-24-methyl-cholesta-6,22-dien-3?-ol(4),(22E,24S)-5?,8?-epidioxy-24-methyl-cholesta-6,22-dien-3?-ol(5),5?,8?-epidioxycholesta-6-en-3?-ol(6)?(24R)-5?,8?-epidioxy-24-ethyl-cholest-6-en-?-ol(7).Compounds 4 and 5 belong to isomeride,among which compound 3-7 was isolated from Pseudoceratina sp.for the first time.Six compounds,one macrolide compound and three amino acid compounds were obtained from Streptomyces parvulus 52-5 fermentation,and identified as: Actinomycin D(8),daucosterol(9),cyclo-((S)-Pro-(R)-Leu)(10),Thymidine(11),3'-O-acetylthymidine(12),3-Indolecarboxylic acid(13),among which compound 8 is the main product of Streptomyces parvulus 52-5.Five compounds,two amino acid compounds,one carboxylic acid compound,two benzoquinone compounds from the concentrated ethyl acetate extract of Streptomyces sp.92-10,and identified as: cyclo(Pro-Ser)(14),cyclo-(phe-gly)(15),aplyolide F(16),geldmycin(17),17-O-demethyl-geldanamycin(18)were isolated from the concentrated ethyl acetate extract of Streptomyces sp.92-10.Compound 16 was isolated from this bacterium for the first time.Ten compounds,four macrolides,two flavonoids,two terpenoids and two amino acid were obtained from the concentrated ethyl acetate extract of Streptomyces sp.94-4,and identified as: venturicidin A(19),venturicidin F(20),venturicidin D(21),venturicidin E(22),Sesquiterpenes L(23),Sesquiterpenes H(24),genistein(25),daidzein(26),cyclo(L-Pro-L-Leu)(27),N-acetyltyramine(28)Compound 19-24 was a new compound and all compounds were isolated from this bacterium for the first time.Twenty-eight comdounds were isolated and purified from the metabolites of Pseudoceratina sp.Compounds aplyolide F(16)?venturicidin F(20)?venturicidin D(21)?venturicidin E(22)?Sesquiterpenes L(23)?Sesquiterpenes H(24)are new compounds isolated from Stretomyces.