Die Umwandlung von 3.5.7.4′-Tetrahydroxyflavanon (Dihydrokämpferol) in Quercetin und Cyanidin beim Buchweizen

Abstract

3.5.7.4′-Tetrahydroxyflavanone-[T] (dihydrokaempferol-[T]) (I) or 3.5.7.4′-Tetrahydroxyflavone-[T] (kaempferol-[T]) (II) together with phenylalanine-[1-¹⁴C] as “internal standard” was fed to buckwheat seedlings and the ¹⁴C and tritium activity was determined in the isolated quercetin and cyanidin. The results prove that I but not II is a very efficient precursor for quercetin and cyanidin and that the introduction of the 3′hydroxyl group can take place with I but not with II as the substrate. It can be concluded that dihydrokaempferol is a common precursor for both quercetin and cyanidin in buckwheat seedlings.