(601j) Applications of Supercritical Fluid Simulated Moving Bed On the Separation of Active Compound From Chinese Herbs

Supercritical carbon dioxide with various cosolvnet can be applied as desorbent for a SMB to reduce the use of organic solvents and to eliminate the dilution effect by chromatographic processing.  A lab-scale SF-SMB with six columns was setup in I-Shou university, Kaohsiung, Taiwan, and several bioactive compounds in the crude extract of Chinese herbs, such as sesamin, sesamolin, resveratrol, emodin, Tashinone, and etc., were sucessfully purified or concentrated by the lab-scale SF-SMB.  The design and operation of a SF-SMB will be illustrated in this presentation, and effects of cosolvent concentartion and pressure drop across the columns will be treated as the elution gradient to enhance the separation.  The Triangle theory based on the volumetric flow rate was also applied to setup the operating conditions and to explain the experimental results.  Compared with traditional liquid desorbent, the supercritical fluid provides fast mass transfer and clear cut of the separation from the crude extract of Chinese herbs, which contains bioactive compounds at low concentration and generally mixed with other multiple components.  With the supercritical carbon dioxide as the major desorbent, the author found that traditional silica used for normal phase chromatography is generally suitable for the SF-SMB.  Examples to purify the bioactive components from Chinese herbs will be presented and difficulties for dealing with the multicomponent system will also be discussed.