STUDIES ON ANTIOXIDANTS FOR VITAMIN A : (XVIII) EFFECT OF QUERCETIN ISOLATED FROM THE BARK OF DOUGLAS FIR ON THE STABILITY OF VITAMIN A

Abstract

Tests of antioxidant activity for vitamin A of quercetin prepared by the treatment with sodium bisulfite of dihydroquercetin isolated from the bark of Douglas fir, resulted in the reconfirmation that antioxidant activity of the substance examined was too weak to be of practical use.