Preparation of bergenin from Ardisia crenata sims and Rodgersia sambucifolia hemsl based on microwave-assisted extraction/high-speed counter-current chromatography

In this paper, a simple method for the rapid extraction, separation and purification of bergenin from Ardisia crenata sims and Rodgersia sambucifolia hemsl by microwave-assisted extraction (MAE) coupled with high-speed counter-current chromatography (HSCCC) was developed. The MAE conditions were optimized and 2.0 g sample was extracted using 60% (v/v) aqueous methanol as extraction solvent with liquid/solid ratio of 10/1 (mL/g) at 60 °C for 15 min. The crude extract of MAE was separated and purified directly by HSCCC using ethyl acetate–n-butanol–water (3:2:5, v/v/v) solvent system. In less than 3.5 h, 18.6 or 25.0 mg of bergenin was obtained from 160 mg crude extract of A. creanta or R. sambucifolia in one-step separation, respectively. The purity of bergenin was over 99% determined by HPLC and its chemical structure was further identified by ESI-MS, 1H NMR and UV. The results indicate that microwave-assisted extraction coupled with high-speed counter-current chromatography is very suitable for the extraction, separation and purification of bergenin from A. creanta and R. sambucifolia.