Separation and purification of steroidal saponins from Paris polyphylla by microwave‐assisted extraction coupled with countercurrent chromatography using evaporative light scattering detection

A method of microwave‐assisted extraction coupled with countercurrent chromatography using evaporative light scattering detection was successfully developed for the separation and purification of steroidal saponins from Paris polyphylla . The main extraction conditions including microwave power, liquid/solid ratio, irradiation time, and extraction temperature were optimized using an orthogonal array design method. A suitable two‐phase solvent system consisting of n‐ heptane/ n‐ butanol/acetonitrile/water (10:19:6:20, v/v/v/v) was employed in the separation and purification of the extracts of P . polyphylla . A total of 7.1 mg polyphyllin VII, 4.3 mg gracillin, 9.2 mg dioscin, and 10.2 mg polyphyllin I were obtained from 1.5 g P . polyphylla in less than 300 min, the purities of which determined by HPLC were 96.7, 97.3, 98.7, and 98.6%, respectively. The identification and characterization of these compounds were performed by LC – ESI ‐ MS and 1 H NMR spectroscopy. The results demonstrated that the proposed method is feasible, economical and efficient for the extraction, separation and purification of effective compounds from natural products.