title: Elution-extrusion counter-current chromatography for the separation of two pairs of isomeric monoterpenes from Paeoniae Alba Radix.
abstract: In this work, a simple and efficient protocol for the rapid separation of two pairs of isomeric monoterpenes from Paeoniae Alba Radix was developed by combining macroporous resin and elution-extrusion counter-current chromatography. The crude extract was firstly subjected to a D101 macroporous resin column eluted with water and a series of different concentrations of ethanol. Then, effluents of 30 and 95% ethanol were collected as sample 1 and sample 2 for further counter-current chromatography purification. Finally, a pair of isomers, 96 mg of compound 1 and 48 mg of compound 2 with purities of 91.1 and 96.2%, respectively, was isolated from 200 mg of sample 1. The other pair of isomers, 14 mg of compound 3 and 8 mg of compound 4 with purities of 93.6 and 88.9%, respectively, was isolated from 48 mg of sample 2. Their purities were analyzed by high-performance liquid chromatography, and their chemical structures were identified by mass spectrometry and (1) H NMR spectroscopy. Compared to a normal counter-current chromatography separation, the separation time and solvent consumption of elution-extrusion counter-current chromatography were reduced while the resolutions were still good. The established protocol is promising for the separation of natural products with great disparity of content in herbal medicines.
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Chu
authors.initials: C
authors.lastname: Chu
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Shidi
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Shengqiang
authors.initials: S
authors.lastname: Tong
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Xingnuo
authors.initials: X
authors.lastname: Li
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Qingyong
authors.initials: Q
authors.lastname: Li
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, P. R. China.
authors.forename: Jizhong
authors.initials: J
authors.lastname: Yan
mesh_terms: D001952:Bridged-Ring Compounds / Q000737:chemistry; D002845:Chromatography / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D003377:Countercurrent Distribution / Q000379:methods; D000431:Ethanol / Q000737:chemistry; D005960:Glucosides / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D039821:Monoterpenes / Q000737:chemistry*; D029596:Paeonia / Q000737:chemistry*; D028321:Plant Preparations / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D014463:Ultrasonography
chemical_list: C468433:6'-O-benzoylalbiflorin; D001952:Bridged-Ring Compounds; D005960:Glucosides; D006027:Glycosides; D039821:Monoterpenes; D028321:Plant Preparations; D012997:Solvents; C015423:peoniflorin; C047591:benzoylpaeoniflorin; C014959:albiflorin; D000431:Ethanol
keywords: Elution-extrusion counter-current chromatography; Macroporous resin; Monoterpenoid glycoside; Paeoniae Alba Radix