FLAVONOL GLYCOSIDES IN THE WET SCALE OF THE DEEP PURPLE ONION (ALLIUM-CEPA L CV RED CREOLE)

Four flavonol glycosides obtianed from the wet scales of the deep purp le onion (Allium cepa L. cv. Res Creole) were identified using combina tion of TLC, PC, UV-visible and H-1 NMR analyses as quercetin 3'-gluco side, 4'-glucoside, 3,4'-diglucoside and isorhamnetin 3-glucoside. Que rcetin 3'-glucoside and isorhanmetin 3-glucoside have not been reporte d in onion tissues before while the other two glycosides have been pre viously reported. The occurence of the isorhamnetin derivative is impo rtant as the compound may contribute to the strong antimicrobial prope rty of this onion cultivar.