COMPARISON OF SUPERCRITICAL CARBON-DIOXIDE EXTRACTION WITH SOLVENT-EXTRACTION OF NONACOSAN-10-OL, ALPHA-AMYRIN ACETATE, SQUALENE AND STIGMASTEROL FROM MEDICINAL-PLANTS

Supercritical carbon dioxide extraction was carried out in the tempera ture range 35 to 60 degrees C and from 10 to 30 MPa in order to obtain phytochemical components from several medicinal plants. These were no nacosan-10-ol (1) from the aerial parts of Ephedra sinica, alpha-amyri n acetate (2) from the root bark of Moots alba, and squalene (3) and s tigmasterol (4) from the entire plant of Spirodela polyrhiza. For comp arison, Soxhlet extraction with n-hexane was also carried out for thes e constituents. In the case of supercritical carbon dioxide extraction of 1, 2 and 4, the extraction yields tended to increase with increase d temperature when the pressure was above 20 MPa. However, extraction yields were maximal at 40 degrees C or 50 degrees C below 15 MPa. When the amounts of extracts obtained by supercritical extraction are comp ared with those by Soxhlet extraction using n-hexane, it is apparent t hat supercritical carbon dioxide extraction can be used as an alternat ive method in the case of squalene and nonacosan-10-ol. (C) 1997 by Jo hn Wiley & Sons, Ltd.