Supercritical carbon dioxide extraction of sea buckthorn (Hippophae rhamnoides L.) pomace

BACKGROUND: The goal of this work was to utilize the sea buckthorn pomace, which is the by‐product of a sea buckthorn juice process. Pilot plant supercritical fluid extraction (SFE) experiments were performed in a 5 × 10^?3 m³ volume high‐pressure vessel. The effects of pressure and temperature on extraction yield and recoveries of biologically active components were studied using a 3² full factorial design. The pressure and temperature were varied over the ranges of 30–46 MPa and 313–353 K, respectively. The extract samples were analysed by TLC‐densitometry, UV/VIS spectrofotometry and HPLC methods. RESULTS: The obtained yields changed between 142–164 g kg^?1, according to the solvent power of the supercritical fluid. The recoveries of the different minor components were (g minor components kg^?1 dried raw material): 2.50–4.25 sitosterol, 0.20–1.60 ursolic acid, 0.04–0.18 carotenoid, 0.35–0.42 total tocopherol. CONCLUSION: By evaluation the designed experiments 46 MPa and 333 K were chosen as the optimum conditions. Copyright © 2007 Society of Chemical Industry