apigenin + S-adenosyl-L-methionine = acacetin + S-adenosyl-L-homocysteine + H(+)
apigenin + s-adenosyl-l-methionine = acacetin + s-adenosyl-l-homocysteine + h(+)
"flavonoid O-methyltransferase"
"flavonoid o-methyltransferase"