Isolation and Purification of Two Constitutes from Dendrobium fimbriatum Hook by High-Speed Counter-current Chromatography Using Stepwise Elution

Abstract

Preparative high-speed counter-current chromatography (HSCCC) was successfully used for the isolation and purification of 2-hydroxyethyl caffeate and denhydroshizukanolide from Dendrobium fimbriatum Hook using stepwise elution with a pair of two-phase solvent systems composed of n-hexane-ethyl acetate-methanol-water at (1:1:1:1, v/v) and (3:1:3:1, v/v). Using a preparative unit of the HSCCC centrifuge, about a 100 mg amount of the sample was separated, yielding 13.3 mg of 2-hydroxyethyl caffeate and 18.0 mg of denhydroshizukanolide at a high purity of over 95%. The peak fraction of HSCCC was identified by ¹H NMR and ¹³C NMR.