3',4',7,8-tetrahydroxyflavone + S-adenosyl-L-methionine = 3',4,7-trihydroxy-8-methoxyflavone + S-adenosyl-L-homocysteine + H(+)
3',4',7,8-tetrahydroxyflavone + s-adenosyl-l-methionine = 3',4,7-trihydroxy-8-methoxyflavone + s-adenosyl-l-homocysteine + h(+)
3',4',7,8-tetrahydroxyflavone + S-adenosyl-L-methionine = 3',4,7-trihydroxy-8-methoxyflavone + S-adenosyl-L-homocysteine + H(+)
3',4',7,8-tetrahydroxyflavone + s-adenosyl-l-methionine = 3',4,7-trihydroxy-8-methoxyflavone + s-adenosyl-l-homocysteine + h(+)