Figure 3.
Biosynthetic experiments documenting that alliarinoside (14) is methionine (1)-derived. [UL-14C]-methionine was administered to A. petiolata leaves and formation of radiolabelled products was monitored by TLC using two different solvent systems to separate hydroxynitrile glucosides (A) and glucosinolates (B), respectively. Representative results obtained with a single leaf are shown. The negatively charged sulfate group of sinigrin is prone to interact with the matrix and consequently cause different migration of sinigrin in the plant extract compared to an external standard. To more accurately determine the migration of alliarinoside and sinigrin in the plant extract, unlabeled internal standards were added to aliquots of leaf extract before samples were applied to the TLC plates (left panels). The spot showing increased staining following charring of the TLC plate indicated the position of the internal standard. O, origin; F, MeOH focus line.