ISOLATION OF FIVE GLYCOSIDES FROM THE BARKS OF ILEX ROTUNDA BY HIGH-SPEED COUNTER-CURRENT CHROMATOGRAPHY

Abstract

Semi-preparative and preparative high-speed counter-current chromatography (HSCCC) were successfully used for isolation of five glycosides from 50% ethanol extract of the dried barks of Ilex rotunda Thunb. (Aquifoliaceae) by using a two-phase solvent system composed of ethyl acetate-n-butanol-water (1:6:7, v/v/v). From 1.0 g of the extract, syringaresinol 4′,4″-di-O-β-D-glucopyranoside ( I , 20.2 mg, 55.4% purity), syringin ( II , 56.8 mg, 98.1% purity), sinapaldehyde glucoside ( III , 26.2 mg, 68.6% purity), syringaresinol 4′-O-β-D-glucopyranoside ( IV , 20.4 mg, 95.3% purity), and pedunculoside ( V , 45.1 mg, 97.3% purity) were obtained by one run of TBE-1000A HSCCC instrument with 1000 mL of column volume. Glycosides I (9.8 mg, 95.5% purity) and III (14.2 mg, 97.8% purity) were further purified by preparative high performance liquid chromatography (HPLC). Their structures were identified by IR, MS, and ¹H and ¹³C NMR studies. Glycoside I was isolated from this plant for the first time.

Keywords:

• glycoside
• high-speed counter-current chromatography (HSCCC)
• Ilex rotunda
• pedunculoside
• syringaresinol 4′,4″-di-O-β-D-glucopyranoside
• two-phase solvent system