The supercritical fluid (SCF) system (Spe-ed SFE-4, Applied Sep- arations, Allentown, United States) was employed for Gac oil extraction. The dried powders (about 2.6 g) were placed into a stainless steel column (length 130.75 mm, 14.22 i.d. and 56.90 i.l) used as the actual extraction vess