Activity-Guided Isolation and Purification of Three Flavonoid Glycosides from Neo-Taraxacum siphonanthum by High-Speed Counter-Current Chromatography
Abstract:DPPH (1,1-diphenyl-2-picryhydrazyl) radical scavenging assay was used to screen different fractions of Neo-Taraxacum siphonanthum ethanol extracts. The potent active fraction was isolated and purified by preparative high-speed counter-current chromatography (HSCCC) with a solvent system composed of n-hexane-n-butanol-water (3:4:7, v/v/v). The flow rate was 1.5 mL/min and resolution speed was 800 rpm. Three flavonoid glycosides with the purity over 99% were obtained and identified as luteolin- 3'-O-β-D-glucopyranoside (I), luteolin-7-O-β-D-glucopyranoside (II), and luteolin-4'-O-β-D-glucopyranoside (III) by ESI-MS, 1H NMR and 13C NMR analysis. Antioxidant activity of three flavonoid glycosides was assessed by DPPH assay, all of which showed potent activity.
Document Type: Research Article
Affiliations: 1: School of Chemistry and Chemical Engineering, Central South University, Changsha, China 2: School of Chemistry and Chemical Engineering, Central South University, Changsha, China,Pharmacogenetics Institute of Central South University, Changsha, China
Publication date: January 1, 2010