An effective high-speed counter-current chromatography method was established for the preparative isolation and purification of two phenylpropanoid glycosides from the Tibetan medicinal plant Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong. With a two-phase solvent system composed of chloroform–n-butanol–methanol–water (4:3:4:5, v/v), 40 mg of an extract of Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong was separated to yield 20 mg of verbascoside and 18 mg of isoacteoside, with purity values of 97 and 98%, respectively. The chemical structures of these two components were identified by proton and carbon nuclear magnetic resonance. In addition, the antioxidant activity of the two phenylpropanoid glycosides was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH)–high-performance liquid chromatography, and the results showed that the two components exhibited strong antioxidant DPPH radical scavenging activity, with IC50 values of 15.6 and 18.9 μg/mL, respectively.
Figure. HPLC chromatograms of different samples: Crude extract from BCM (A);
DPPH–HPLC of the crude extract from BCM (B);
HSCCC of two target compounds (peak fractions I and II)(C, D).
HPLC conditions: column, Eclipse XDB–C18 (5 μm, 4.6× 150 mm);
mobile phase, methanol–water (0–60 min, 28–45% methanol);
flow rate,1.0 mL/min; column temperature, 258C; detection wavelength, 280 nm.
Additional Information:
1 Author Information:Chen Chen, Xiaohui Zhao, Huilan Yue, Yulin Li and Tao Chen
Correspondence: Email: xhzhao@nwipb.ac.cn
2 Published:
Journal of Chromatographic Science, 2013;1–5
doi:10.1093/chromsci/bmt048