Metabolism of Sinapine in Mustard Plants. I. Degradation of Sinapine into Sinapic Acid & Choline

Abstract

A sensitive colorimetric assay method for sinapine based on the formation of water-insoluble complexes between Reinecke salt and quaternary N bases has been devised. A study of the quantitative changes of sinapine in a test plant, Brassica hirta. showed that there is a rapid exponential disappearance of sinapine following germination. A crude extract prepared from mustard seedlings was shown to hydrolyze sinapine into sinapic acid and choline. No such activity could be detected in extracts of seeds. On the basis of unit protein there appeared to be a higher concentration of the esterase in the roots of the seedlings.