Identification of Taxifolin Present in the Azuki Bean as an Oviposition Stimulant of the Azuki Bean Weevil

Abstract

As a new constituent of the oviposition stimulant of the azuki bean weevil, taxifolin [3,5,7,3’,4’-pentahydroxyflavanone] (1) was identified from the aqueous extract of the azuki beans, active at 2.0 ng per glass bead. At the same time we isolated quercetin [3,5,7,3’,4’-pentahydroxyflavone] (2) as a non-active ingredient. Since the related compound, D-catechin [(25,3S)-3,5,7,3’,4’-pentahydroxyflavan] (3) is also known as the stimulant, the following structure activity relationship might be suggested; 3 (active at 0,2-2 ng)>l (active at 2 ng) >2 (inactive). © 1994, Pesticide Science Society of Japan. All rights reserved.