The Application of Simulated Moving-Bed Chromatography for the Separation of Ginsenosides in Sanchi Ginseng and American Ginseng

In this study, the separation of ginsenosides from the crude extract of Sanchi ginseng and American ginseng, obtained by aqueous ethanol extraction, was conducted in a simulated moving bed (SMB) with cleaning in place (CIP) design. Concentrated products with 86.2%, w/w, and 91.5%, w/w, of ginsenosides were obtained by the utilization of CIP-SMB for Sanchi and American ginseng, respectively. This study reveals that CIP-SMB could enrich ginsenosides by removing the retained impurities, which were initially extracted by aqueous ethanol and not removed by either the antisolvent precipitation for Sanchi ginseng or the ethyl acetate extraction for American ginseng. Although the ginsenosides in both ginsengs are similar, the difficulty in applying chromatography to the crude extract differs. A natural crude extract normally contains compounds with significant difference in retention. A traditional SMB with 4 sections will be, consequently, unable to continuously separate the natural products. This study develops methods for pretreating the crude extract and demonstrates the feasibility of continuously separating ginsenosides by using SMB. SMB is an effective technology for large-scale chromatography and can generally resolve solvent and energy consumption problems. This is expected to promote the industrial use of SMB for the production of concentrated ginsenosides as active pharmaceutical ingredients.