FLAVANONE SYNTHASE - SIMPLE AND RAPID ASSAY FOR THE KEY ENZYME OF FLAVONOID BIOSYNTHESIS

It is suggested that flavanone synthase activity should be measured when the key reaction of flavonoid biosynthesis is to be tested. A simple and rapid procedure for the determination of flavanone synthase activity, based on extraction of the 14C-labelled product(s) into ethylacetate, is described. The enzyme can be stored under appropriate conditions for several weeks without significant loss of activity. Results obtained with cell suspension cultures of parsley indicate that the activity of flavanone synthase is regulated differently from the activity of phenylalanine ammonia-lyase, an enzyme frequently referred to as a key enzyme of flavonoid biosynthesis. © 1979.