Production of an α-pyrone metabolite and microbial transformation of isoflavones by an Indonesian sp.

A benzyl-α-pyrone metabolite, streptpyrone A (), was obtained together with three known isoflavonoids, daidzein-7--α-l-rhamnoside (), genistein-7--α-l-rhamnoside (), and daidzein (), from the culture broth of an Indonesian actinomycete sp. TPU1401A. The structure of , elucidated based on its spectroscopic data, has been reported as a synthetic compound. However, this is the first report of the isolation of as a metabolite of microbial origin. Strain TPU1401A exhibited the ability to transform the isoflavone aglycones and genistein () into the 7--glycosides and , respectively. Compounds and promoted the growth of strain TPU1401A more effectively than compounds and . These results suggest that strain TPU1401A utilizes isoflavone glycosides to promote growth by transforming isoflavones through microbial glycosidation.