Enrichment and purification of pedunculoside and syringin from the barks of Ilex rotunda with macroporous resins.

Jiubiying, the dried barks of Ilex rotunda Thunb. (Aquifoliaceae), has been used as herbal tea and traditional Chinese medicine for heat-clearing, detoxifying, dehumidification, and odynolysis. Pedunculoside and syringin are two main bioactive components. For the new drug development, we tried to isolate and purify several chemical constituents from Jiubiying by high-speed counter-current chromatography (HSCCC). The two-phase solvent system used was composed of ethyl acetate-n-butanol-water (1:6:7, v/v/v). From 1.0 g of Jiubiying extracts syringaresinol 4',4″-bis-O-β-D- glucopyranoside (I, 20.2 mg), syringin (II, 56.8 mg), sinapaldehyde glucoside (III, 26.2 mg), syringaresinol 4'-O-β-D-glucopyranoside (IV, 20.4 mg), and pedunculoside (V, 45.1 mg) were obtained by one run of TBE-1000A HSCCC machine with 1000 mL of column volume. Their structures were identified by IR, MS, and extensive NMR studies. Syringaresinol 4',4″-bis-O-β-D-glucopyranoside (I) was isolated from this plant for the first time.