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A new antibiotic complex of six aureolic acids was isolated from the marine sediment-associated strain Streptomyces sp. KMM 9048. Four of the compounds (3-6) were found to be similar but not identical to the known chromomycins A₂, A₃, demethyl chromomycin A₃ and A₄. The two remaining.compounds; A₂₋₁ (1) and A₃₋₁ (2), were established as novel chromomycin analogs, which did not contain sugar B. Spectroscopic methods including ID and 2D NMR, and HRMS and MS/MS were applied for structure elucidation. Compounds 1-5 showed strong antimicrobial activity against Gram-positive indicatory bacteria Enterococcusfaecium, Staphylococcus aureus, S. epidernzidis, and Bacillus subtilis. Antitumor assay indicated that all tested compounds, in different manners, inhibited colony formation of RPMI-7951 and SK-Mel-28 cancer cells. This is the first study reporting the inhibitory effects of chromomycin analogs 1-5 on the colony formation of the investigated cancer cell lines. Compound 3, in a concentration of 5 nM, inhibited colony formation of RPMI-7951 and SK-Mel-28 cells by 82 % and 72 %, respectively. Our finding indicated that, of the compounds tested, 3 and 4 are promising anticancer and antimicrobial agents.

A new linear glyceryl acid derived heptapeptide (1), together with known isocoumarin antibiotic, Y-05460M-A (2), were isolated from the culture of the deep sea sediment strain SI 79 classified as "Paenibacillus profundus" sp. nov. Their structures were determined by 1D- and 2D- NMR techniques and ESI-MS/MS experiments. HPLC analysis of the Marfey derivatives in comparison to their analogs of authentic amino acids revealed that all amino acids in peptide 1, with an exception of Val, have the D-configuration. The compound 1 showed inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Enterococcus faecium as well as cytotoxic and moderate colony growth inhibitory activity against SK-MEL-28 cell line.

Two new angucyclines, saccharothrixmicines A (2) and B (3), together with three known diketopiperazines 4-6 were isolated from the actinomycete Saccharothrix espanaensis An 113 associated with the marine mollusk Anadara broughtoni. Their structures were determined by HRESI-MS and 1D and 2D NMR. Compounds 2 and 3 differ in aglycone and glycosidic bond type. 2 is an alpha-L-6-deoxyaltrose-phenylglycoside of a benz[a]anthraquinone aglycone, while 3 is an O-glycoside of the same sugar linked to C-7 of the known angucyclinone (1). A saccharothrixmicine-containing fraction exhibited activity towards Candida albicans and Xanthomonas sp. pv. badrii whereas the diketopiperazines showed antibiotic activities against Vibrio alginolyticus and Vibrio parahaemolyticus.