label: 3'-O-methyltricetin + S-adenosyl-L-methionine <=> 3',5'-di-O-methyltricetin + S-adenosyl-L-homocysteine + H(+)
label_lc: 3'-o-methyltricetin + s-adenosyl-l-methionine <=> 3',5'-di-o-methyltricetin + s-adenosyl-l-homocysteine + h(+)