title: Separation of four flavonol glycosides from Solanum rostratum Dunal using aqueous two-phase flotation followed by preparative high-performance liquid chromatography.
abstract: Aqueous two-phase flotation followed by preparative high-performance liquid chromatography was used to separate four flavonol glycosides from Solanum rostratum Dunal. In the aqueous two-phase flotation section, the effects of sublation solvent, solution pH, (NH4)2SO4concentration in aqueous solution, cosolvent, N2flow rate, flotation time, and volumes of the polyethylene glycol phase on the recovery were investigated in detail, and the optimal conditions were selected: 50 wt% polyethylene glycol 1000 ethanol solvent as the flotation solvent, pH 4, 350 g/L of (NH4)2SO4concentration in aqueous phase, 40 mL/min of N2flow rate, 30 min of flotation time, 10.0 mL of flotation solvent volume, and two times. After aqueous two-phase flotation concentration, the flotation products were purified by preparative high-performance liquid chromatography. The purities of the final products A and B were 98.1 and 99.0%. Product B was the mixture of three compounds based on the analysis of high-performance liquid chromatography at the temperature of 10°C, while product A was hyperoside after the identification by nuclear magnetic resonance. Astragalin, 3'-O-methylquercetin 3-O-β-d-galactopyranoside, and 3'-O-methylquercetin 3-O-β-d-glucopyranoside were obtained with the purity of 93.8, 97.1, and 99.2%, respectively, after the further separation of product B using preparative high-performance liquid chromatography.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, P. R. China.
authors.forename: Lin
authors.initials: L
authors.lastname: Chang
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, P. R. China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Shao
authors.affiliation: China National Institute of Standardization, Haidian District, Beijing, P. R. China.
authors.forename: Xingjun
authors.initials: X
authors.lastname: Xi
authors.affiliation: China National Institute of Standardization, Haidian District, Beijing, P. R. China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, P. R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wei
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D044948:Flavonols / Q000302:isolation & purification; D006027:Glycosides / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D032322:Solanum / Q000737:chemistry*
chemical_list: D044948:Flavonols; D006027:Glycosides
keywords: aqueous two-phase flotation; flavonol glycosides; preparative high-performance liquid chromatography; solanum rostratum Dunal