Four new diphenyl ether derivatives from a mangrove endophytic fungus Epicoccum sorghinum.

Four new diphenyl ethers, named epicoccethers K-N (1-4), were purified from the fermentation medium of a fungus Epicoccum sorghinum derived from Myoporum bontioides, and identified through HR-ESI-MS and NMR spectral analysis. Except that compound 1 showed moderate antifungal activity against Penicillium italicum and Fusarium graminearum, the other three compounds showed stronger activity against them than triadimefon. All of them showed moderate or weak antibacterial activity towards Staphylococcus aureus and Escherichia coli with O6 and O78 serotypes except that 3 was inactive to E. coli O6.

A new di-O-prenylated flavone from an actinomycete Streptomyces sp. MA-12.

A new di-O-prenylated flavone, named 7,3'-di-(γ,γ-dimethylallyloxy)-5-hydroxy-4'-methoxyflavone (1), was isolated from the culture broth of the endophytic actinomycete Streptomyces sp. MA-12 isolated from the root of the semi-mangrove plant Myoporum bontioides A. Gray. The structure of 1 was determined by comprehensive spectroscopic methods, including 1D and 2D NMR experiments (COSY, HMQC, and HMBC). Primary bioassays showed that 1 at concentration of 0.25 mM had moderate inhibitory activity against three plant pathogenic fungi including Colletotrichum musae, Gibberella zeae (Schweinitz) Petch, and Penicillium citrinum Thom.

A new diimide derivative from the co-culture broth of two mangrove fungi (strain no. E33 and K38).

A new diimide derivative, named (-)-byssochlamic acid bisdiimide (1), was isolated from the mixed broth of two mangrove fungi (strain no. K38 and E33) from the South China sea coast. The structure of 1 was determined by comprehensive spectroscopic methods, including 1D and 2D NMR (COSY, HMQC, and HMBC) and semi-synthesis. Primary bioassays showed that 1 had weak cytotoxic activity against Hep-2 and HepG2 cells.

[Secondary metabolites of a marine mangrove fungus (Penicillium sp. no. 2556) from South China Sea].

The metabolites of a marine mangrove fungus (Penicillium sp. No. 2556) were studied in this paper and six compounds were isolated from the fermentation liquid. Their structures were elucidated by spectroscopy methods as Sch54796 (1), Sch54794 (2), 4-hydroxybenzoic acid (3), urail (4), succinic acid (5), Vermopyrone (6). Among them, compounds 1, 2 and 6 were firstly isolated from Penicillium sp., Coumpounds 1 and 2 remarkably inhibited the growth of cancer cell lines hep2 and hepG2.

[Secondary metabolites of a marine actinomycete Streptomyces sp. (No. 195-02) from South China Sea].

The metabolites of a marine streptomyces sp. actinomycete (No. 195-02) were studied and eight compounds were isolated from the fermentation liquid, structures were elucidated by spectroscopy methods as p-hydroxy-benzonitrile (1), 2-methyl-furan-3-carboxylic acid(2), furan-2-carboxylic acid (3), cyclo(Phe-Phe) (4), cyclo(Leu-Ileu) (5), nicotinic acid (6), 2-(1H-indol-3-yl) acetic acid (7) and bis(2-ethylhexyl) phthalate (8). The compounds 1, 3 and 8 were firstly isolated from Streptomyces sp., compounds 4 -7 were firstly found from marine actinomycetes. Coumpouds 4 and 5 evidently inhibited the growth of cancer cell lines hepG2 and hep2 at the concentration of 50 microg/ml.

[Study on IR of interaction of three modified-starchs and crystallization of calcium carbonate].

Three types of CaCO3 can be synthesized through biomimetic synthesis. In the present work, carboxymethyl-starch, etherified-starch, and phosphate-starch, used as organic matrices, were studied by FTIR. The result shows that the intensity of C-O peaks of the three modified-starchs changed. In addition, the intensity of C-O peaks was weakened or vanished obviously with the increase in time. The action mechanism of the modified-starchs and CaCO3 was briefly discussed.