Research on the antioxidant activity of metabolites from a sponge-derived fungus Alternaria sp. F49 / 药学学报

To study the chemical constituents from the the deep-sea fungus Alternaria sp. F49. Seven compounds were isolated from the EtOAc extract by using silica gel, Sephadex LH-20, ODS and HPLC methods. Based on the spectroscopic analysis, their structures were identified as (8R)-5-O-methyl-orcinotriol (1), orcinotriol (2), α-acetylorcinol (3), 3'-hydroxyalternariol 5-O-methyl ether (4), altenusiol (5), altenusin (6), and 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (7). (8R)-5-O-Methyl-orcinotriol (1) is a new phenolic compound which has never been reported in the literature. Compounds 4-7 showed strong DPPH free radical scavenging activity; whereas compounds 1-7 showed strong ABTS free radical scavenging activity.

Ligand fishing: a strategy for rapidly screening bioactive compounds from organism extracts / 药学学报

Natural products are valuable resources for discovering new drugs. So far, screening bioactive compounds from organism extracts is still an important and challenging task. Traditional biometric guided method involves repeated fractionation steps and bioactivity tests, which are time-consuming, labor-consuming, and inefficient. Ligand fishing is a bioanalysis method for screening ligands from complex organism extracts based on intermolecular affinity interactions. It has the characteristics of strong specificity, high efficiency, and less requirement for sample pretreatment. In this review, we summarize the classification of ligand fishing strategy and its application in enzyme inhibitors screening. Finally, the development prospects of this technology are forecasted.

A new polyketide from a sponge-derived fungus / 药学学报

A new polyketide:3R, 5R-(-)-talaroflavone (2), along with 15 known compounds were isolated from a EtOAc extract of a sponge-derived fungus Alternaria sp. F49. Compounds 1-2 and 3-4 were separated as two pairs of enantiomers by chiral HPLC from Ⅰ and Ⅱ. The structures of compounds 1-16 were elucidated by means of NMR and MS. Furthermore, the absolute configurations of compounds 1-2 were determined by single crystal X-ray diffraction experiment and CD analyses. Compounds 6, 8-10 were isolated from this genus (Alternaria sp.) for the first time. Compound 16 showed moderate COX-2 enzyme inhibitory activity with IC50of 7.3 μmol·L-1.