Abstract
The biosynthesis of O–alkyl-furocoumarins has been investigated in Ammi majus, Apium graveolens and Petroselinum sativum, feeding these herbs with labeled psoralen and with labeled rutaretin (8–hydroxymarmesin).
Only psoralen was efficaciously incorporated in isolated O–alkyl-furocoumarins, while
rutaretin was practically not utilized. These data show that in these herbs O–alkyl-furocoumarins
derives from the hydroxylation of psoralen, which behaves as a transient precursor
for other furocoumarins and therefore cannot be accumulated. On the other hand marmesin
cannot be hydroxylated in the three herbs.
