title: Preparative separation of five flavones from flowers of Polygonum cuspidatum by high-speed countercurrent chromatography.
abstract: A preparative high-speed countercurrent chromatography method was successfully used for the isolation of five minor flavones from Polygonum cuspidatum flowers. Among them, three compounds were obtained from P. cuspidatum for the first time. A twin two-phase solvent system composed of n-hexane/ethyl acetate/ethanol/water (1:6:3:6, v/v/v/v) and petroleum ether/ethyl acetate/methanol/water (2:4:3:3, v/v/v/v) was developed. Compounds were obtained from the fraction B and fraction C prepurified by silica gel column chromatography. Five minor compositions, 6.8 mg of hesperidin, 11.2 mg of phloridzin, 4.9 mg of luteolin, 5.3 mg of hyperin, and 3.7 mg of luteoloside were obtained from 140 mg of the fraction B and 110 mg of fraction C with a purity of 95.3, 96.4, 98.0, 96.8, and 95.3%, respectively, as determined by high-performance liquid chromatography. The structures of these compounds were identified by (1) H and (13) C NMR spectroscopy.
authors.affiliation: State Key Laboratory of Crop Biology, Shandong Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, China.
authors.forename: Yinshi
authors.initials: Y
authors.lastname: Sun
authors.forename: Shubo
authors.initials: S
authors.lastname: Gu
authors.forename: Linlin
authors.initials: L
authors.lastname: Guo
authors.forename: Xue
authors.initials: X
authors.lastname: Xia
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Jianhua
authors.initials: J
authors.lastname: Wang
mesh_terms: D003377:Countercurrent Distribution / Q000379:methods*; D045468:Fallopia japonica / Q000737:chemistry*; D047309:Flavones / Q000737:chemistry / Q000302:isolation & purification*; D035264:Flowers / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D047309:Flavones; D010936:Plant Extracts
keywords: Flavones; High-speed countercurrent chromatography; Polygonum cuspidatum; Preparative separation