label: sterigmatocystin + S-adenosyl-L-methionine = 8-O-methylsterigmatocystin + S-adenosyl-L-homocysteine + H(+)
label_lc: sterigmatocystin + s-adenosyl-l-methionine = 8-o-methylsterigmatocystin + s-adenosyl-l-homocysteine + h(+)