Separation and purification of flavonols myricetin, quercetin and kaempferol in cooked Pu- erh tea

In this paper, Yunnan cooked Pu- erh tea was used as experiment material, separation and purification of flavonols were investigated with different concentrations of ethanol as eluent by column chromatography of resin and SephadexTMLH-20, combined with high- performance liquid phase chromatography ( HPLC) method, and the main flavonols were isolated and characterized. The results showed that: the extract of cooked Pu- erh tea with different concentrations ( 10%, 30%, 50%, 70%, 90%) of ethanol by MCI GEL CHP 20P ( 75 ¹50 μm) , the myricetin with the HPLC purity of 96.0% and the quercetin with the HPLC purity of 98.5% were isolated from elution 70%eluent with 90% ethanol while kaempferol with the HPLC purity of 95.6% was isolated from elution 90% eluent with70% ethanol by SephadexTMLH-20.