In enzymology, an isoflavone 7-O-methyltransferase is an enzyme that catalyzes the chemical reaction S-adenosyl-L-methionine + a 7-hydroxyisoflavone ⇌ {\displaystyle \rightleftharpoons } S-adenosyl-L-homocysteine + a 7-methoxyisoflavoneThus, the two substrates of this enzyme are S-adenosyl methionine and 7-hydroxyisoflavone, whereas its two products are S-adenosylhomocysteine and 7-methoxyisoflavone. Wikipedia