Formation of polyhydroxylated isoflavones from the isoflavones genistein and biochanin A by bacteria isolated from tempe

Two Micrococcus or Arthrobacter bacterial strains hydroxylate the 5-hydroxyisoflavones genistein ( R = OH, R 1 = H ) and biochanin A ( R = OH, R 1 = Me) in positions 6 or 8 in good yields. The transformation reactions are recommended for biotechnological application. Two tempe-derived bacterial strains identified as Microccus or Arthrobacter species were shown to transform the 5-hydroxyisoflavones biochanin A and genistein to polyhydroxylated isoflavones by hydroxylation reactions at positions C-6 and C-8. Both strains transformed genistein to 5,6,7,4′-tetrahydroxyisoflavone and 5,7,8,4′-tetrahydroxyisoflavone and biochanin A to 4′-methoxy-5,7,8-trihydroxyisoflavone, whereas only strain I converted biochanin A to 4′-methoxy-5,6,7-trihydroxyisoflavone. The structures of these transformation products were elucidated by spectroscopic techniques.