Author(s): Paramita Das, Padmavathi P Prabhu, Jitender Reddy
In this study, penta hydroxy flavonoid quercetin-4-glycoside was isolated from the ethanolic extract of Allium cepa which was then eluted in the solvents chloroform and methanol. The crude ethanolic extract was collected and subjected to column chromatography and sub fractionated with solvent chloroform and methanol. Isolate was further processed and selected sub fraction was subjected to fresh column chromatography. Washing was continued till TLC shows a single spot observed under UV at 254 nm and 366nm after spraying ANS reagent. Quercetin-4-glycoside was established on the chemical and spectral analysis and HPLC-PDA was developed for the standardization and estimation of compound. The results of analysis of the compound suggested that the compound may be used as a marker for standardization, and the developed isolation method is cost effective compared to all other existing methods reported in literature.