Biotransformation of daidzein, genistein and biochanin A by three selected filamentous fungi was investigated. As a result of biotransformations, six glycosylation products were obtained. Fungus Beauveria bassiana converted all tested isoflavones to 4″-O-methyl-7-O-glucosyl derivatives, whereas Absidia coerulea and Absidia glauca were able to transform genistein and biochanin A to genistin and sissotrin, respectively. In the culture of Absidia coerulea, in addition to the sissotrin, the product of glucosylation at position 5 was formed. Two of the obtained compounds have not been published so far: 4″-O-methyl-7-O-glucosyl biochanin A and 5-O-glucosyl biochanin A (isosissotrin). Biotransformation products were obtained with 22%–40% isolated yield.
products were obtained: From flavone–flavone 2′-O-β-d-(4′′-O-methyl)-glucopyranoside, flavone4′-O-β-d-(4′′-O-methyl)-glucopyranoside and 3′-hydroxyflavone 4′-O-β-d-(4′′-O-methyl)-glucopyranoside; from 5-hydroxyflavone–5-hydroxyflavone 4′-O-β-d-(4′′-O-methyl)-glucopyranoside; from 6-hydroxyflavone–flavone 6-O-β-d-(4′′-O-methyl)-glucopyranoside; from 7-hydroxyflavone–flavone 7-O-β-d-(4′′-O-methyl)-glucopyranoside;