title: Preparative separation of four triterpene saponins from radix astragali by high-speed counter-current chromatography coupled with evaporative light scattering detection.
abstract: Four triterpene saponins, including astragaloside IV, astragaloside II, astragaloside I and acetylastragaloside I, were successfully isolated and separated by high-speed counter-current chromatography coupled with evaporative light scattering detection from Radix Astragali using stepwise elution with a pair of solvent systems composed of n-hexane:ethyl acetate:ethanol:water in volume ratios of 1:0.6:0.6:1 and 1:1:1:1 (by volume). The isolation produced 26.5 mg astragaloside IV, 28.2 mg astragaloside II, 48.7 mg astragaloside I and 17.6 mg acetylastragaloside I with purities of 97.6, 96.4, 98.8 and 96.8%, respectively, determined by high-performance liquid chromatography from 250 mg crude extract. The chemical structures of the isolated compounds were identified by UV, NMR and MS, and confirmed by authentic standards.
authors.affiliation: School of Pharmacy, Dalian Medical University, Dalian 116027, People's Republic of China. jinyongpeng2005@163.com
authors.forename: Jinyong
authors.initials: J
authors.lastname: Peng
authors.forename: Fuqiu
authors.initials: F
authors.lastname: Dong
authors.forename: Yan
authors.initials: Y
authors.lastname: Qi
authors.forename: Xu
authors.initials: X
authors.lastname: Han
authors.forename: Youwei
authors.initials: Y
authors.lastname: Xu
authors.forename: Lina
authors.initials: L
authors.lastname: Xu
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Xu
authors.forename: Kexin
authors.initials: K
authors.lastname: Liu
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhu
mesh_terms: D027883:Astragalus Plant / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003377:Countercurrent Distribution / Q000379:methods*; D015394:Molecular Structure; D012503:Saponins / Q000737:chemistry*; D014315:Triterpenes / Q000737:chemistry*
chemical_list: D012503:Saponins; D014315:Triterpenes