Isolation and Purification of Sesquiterpene Lactones from Ixeris sonchifolia (Bunge) Hance by High-Speed Counter- Current Chromatography and Semi-Preparative High Performance Liquid Chromatography
Purpose: To isolate and purify sesquiterpene lactones from Ixeris sonchifolia (Bunge) Hance by highspeed counter-current chromatography (HSCCC).
Methods: I. sonchifolia was extracted with water and then loaded on a glass column (10 ~ 1500 cm containing 3000g D101 macroporous resin) where various concentrations of aqueous ethanol (0, 10, 30, 50, and 95 %) were used to elute the column successively. The 50 % ethanol fraction was purified by HSCCC using a solvent system comprised of ethyl acetate: n-butanol: methanol: water (4: 6: 1: 20, v/v), and semi-preparative high performance liquid chromatography (HPLC). The chemical structures of the
components obtained were further confirmed by high-resolution mass spectroscopy (MS) and nuclear magnetic resonance spectroscopy (NMR).
Results: Three compounds, including ixerin Z1 (0.7 mg), ixerin Z (11.4 mg), and 11, 13α-dihydroixerin Z (8.2 mg), with purity of 96.2, 98.2, and 98.4 %, respectively, were obtained from 200 mg each of the 50 % ethanol fraction.
Conclusion: HSCCC is a rapid and effective method for isolating and purifying sesquiterpene lactones from I. sonchifolia.
Keywords: Sesquiterpene lactones, High-speed counter-current chromatography, Ixeris sonchifolia, Ixerin, 13α-Dihydroixerin