The tissue distributions of sinapic acid esters (1-sinapoylglucose, sinapolyl-L-malate, 6,3'-disinapoylsucrose), kaempferol glycosides, free malic acid and of the enzyme involved in the synthesis of sinapoyl-L-malate, 1-sinapoylglucose: L-malate sinapoyltransferase (SMT), have been investigated in