ABSTRACT
Pyranone derivative I was isolated from fermented broth of isolated marine bacterial strain Vibrio sp. SKMARSP9. The compound I was characterized, and evaluated for its antimicrobial properties. The isolated strain was identified based on 16S rRNA based phylogenetic analysis. The molecular analysis data suggested that this strain is closely related to Vibrio ruber, Vibrio sp. MSSRF10 and Vibrio rhizosphaerae. The best fermentative growth of this isolate was achieved under halophilic conditions and grew efficiently at 30 °C in the presence of 12 % NaCl. The compound I production by this strain is associated with growth. The unpurified extract is hydrophobic in nature, and released only during late growth phase. The extract was purified and characterized by spectral data using NMR, DEPT, and ESI-MS. The purity of I was 97 % which was confirmed by HPLC. The pyranone derivative I exhibited >50 % antioxidant activity and broad spectrum antimicrobial properties against gram negative and gram positive strains. Molecular docking analysis revealed that this pyranone derivative I may be a potential candidate at pharmaceutical sector.
ABSTRACT
A comprehensive investigation of chemical constituents from brown algae Stoechospermum marginatum yielded ten known spatane compounds (1-10). To develop the compound libraries on these scaffolds, a series of semi synthetic derivatives was prepared (1a-1d, 2a, 4a, 11 and 12) and investigated for their anti-microbial and anticancer activities. The results indicated that compounds 2a, 4, 1b and 4a exhibited potent cytotoxic activities against B16F10 cancer cell line with IC50 values of 3.28, 3.45, 3.62 and 4.11 µg/ml respectively, which are comparable to the standard drug (etoposide IC50=4.12 µg/ml). In addition, 4 and 1b were also manifested potent antimicrobial activities against tested bacterial and fungal strains. This is the first Letter on the synthesis and biological activities of these novel derivatives.
