New production of (R)-(-)-5-bromomellein, a dihydroisocoumarin derivative from the marine-derived fungus Aspergillus ochraceus

作者：Yun Keumja^*; Feng Zhile; Choi Hong Dae; Kang Jung Sook; Son Byeng Wha

来源：Chemistry of Natural Compounds, 2013, 49(1): 24-26.

DOI：10.1007/s10600-013-0496-1

• (R)-(-)-5-bromomellein
• marine-derived fungus
• Aspergillus ochraceus

The addition of NaBr to the fermentation of a marine isolate of the fungus Aspergillus ochraceus resulted in induced production of a new brominated mellein analogue. A new radical-scavenging halogenated isocoumarin, (R)-(-)-5-bromomellein (1), and three known compounds, (R)-(-)-mellein (2), clavatol (3), and circumdatin A (4), were isolated from the culture. The structure of 1 was assigned through a combination of spectroscopic data analyses. Compounds 1-4 exhibited mild radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH). The IC50 values of each compounds (1-4) were 24, 25, 30, and 32 mu M, respectively, which were less active than the positive control, L-ascorbic acid (IC50, 20.0 mu M).

• 出版日期2013-3