Biotransformation for multiple regio-selective hydroxylation of isoflavonoid

Development of microbial and enzymatic platforms for the production of pharmaceuticals and other industrial chemicals is an important area of research. Flavonoid and isoflavonoid oxidation is of potential importance in the synthesis of active antioxidants for biological activity in human. Especially, ortho-dihydroxyisoflavones (7,8,4′-trihydroxyisoflavone, 6,7,4′-trihdyroxyisoflavone and 7,3′,4′-trihydroxyisoflavone) are a growing scientific interest to enhance their health-related quality in human. The roles of biocatalysts from microorganisms which are called as treasure islands for natural products of medicine and antibiotics are not well understood. Thus, substrate specificity study on enzymes may give a solution for elucidation their roles. In this study, it was elucidated an enzyme had substrate specificity for regiospecific multiple hydroxylation to 7,8,4′-trihydroxyisoflavone, 6,7,4′-trihdyroxyisoflavone and 7,3′,4′-trihydroxyisoflavone. We demonstrated here that the biotransformation of daidzein can be significantly improved by modulating the monooxygenase and redox partner. The studies presented here provide the basis for future strain optimization to improve ortho-dihydroxyisoflavones production.