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 sea buckthorn juice process. Pilot plant supercritical fluid extraction (SFE) experiments were performed in a 5 x 10(-3) m(3) volume high-pressure vessel. The effects of pressure and temperature on extraction yield and recoveries of biologically active components were studied using a 3(2) 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. (C) 2007 Society of Chemical Industry.