title: Efficient counter-current chromatographic isolation and structural identification of two new cinnamic acids from Echinacea purpurea.
abstract: Two new cinnamic acids, 2-O-caffeoyl-3-O-isoferuloyltartaric (3), and 2, 3-di-O-isoferuloyltartaric acid (5), along with three known caffeic acids, cichoric acid (1), 2-O-caffeoyl-3-O-feruloyltartaric acid (2) and 2-O-caffeoyl-3-O-p-coumaroyltartaric acid (4), have been successfully isolated and purified from Echinacea purpurea. In this study, we investigated an efficient method for the preparative isolation and purification of cinnamic acids from E. purpurea by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent composed of n-hexane-ethyl-acetate-methanol-0.5% aqueous acetic acid (1:3:1:4, v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase, with a flow rate of 1.6 mL/min. From 250 mg of crude extracts, 65.1 mg of 1, 8.3 mg of 2, 4.0 mg of 3, 4.5 mg of 4, and 4.3 mg of 5 were isolated in one-step, with purities of 98.5%, 97.7%, 94.6%, 94.3%, and 98.6%, respectively, as evaluated by HPLC-DAD. The chemical structures were identified by electro spray ionization mass spectrometry (ESI-MS) and one- and two-dimensional NMR spectra. HSCCC was very efficient for the separation and purification of the cinnamic acids from
authors.affiliation: National Research Center of Engineering Technology for Utilization of Functional Ingredients from Botanicals & Hunan Province Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha, Hunan, P.R. China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: JiaYin
authors.initials: J
authors.lastname: Li
authors.forename: MiLu
authors.initials: M
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Hu
authors.forename: Jun
authors.initials: J
authors.lastname: Tan
authors.forename: Zhong Hua
authors.initials: ZH
authors.lastname: Liu
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002934:Cinnamates / Q000737:chemistry* / Q000302:isolation & purification; D003377:Countercurrent Distribution; D020900:Echinacea / Q000737:chemistry*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D018517:Plant Roots / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: C576851:2,3-di-O-isoferuloyltartaric acid; C576850:2-O-caffeoyl-3-O-isoferuloyltartaric acid; D002934:Cinnamates; D007202:Indicators and Reagents