Preparative separation of polyphenols from the flowers of Paeonia lactiflora Pall. by high-speed counter-current chromatography

•High-speed counter-current chromatography was used for the first time to separate and purify polyphenols from the flowers of Paeonia lactiflora Pall.•Eight high polarity compounds were separated for the first time from Paeoniae lactiflora flowers.•The results demonstrated that KD value can be ranged from 1 to 4 for separation high polarity compounds.

High-speed counter-current chromatography was used to separate and purify polyphenols for the first time from the flowers of Paeonia lactiflora Pall. with two solvent systems as follows: petroleum ether–ethyl acetate–H2O (1:9:10, v/v/v/v) and petroleum ether–ethyl acetate–butanol–H2O (1:9:0.5:10, v/v/v/v). Eight compounds were separated successfully in single run which were identified as quercetin-3-O-(6″-O-galloyl)-glucoside (I, 41.5 mg), 1,2,3,4,6-trigalloyl-β-d-glucose (II, 106.2 mg), quercetin-3-O-β-d-glucoside (III, 42.3 mg), kaempferol-3-O-(6″-O-galloyl)-glucoside (IV, 23.5 mg), isohamnetin-3-O-β-d-glucoside (V, 34.1 mg), kaempferol (VI, 14.8 mg), kaempferol-3-O-β-d-glucoside (VII, 32.6 mg), kaempferol-7-O-β-d-glucoside (VIII, 23.8 mg) by electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR). The purities of compounds I–VIII were all over 97.0% as determined by HPLC.