Supercritical CO₂ extraction of biological active compounds from loquat seed

Amygdalin and β-sitosterol from roasted powder and ground unroasted loquat seed were extracted using supercritical CO₂. Loquat seed is the waste of loquat fruit (Eribotrya japonica), that called biwa in Japan. Loquat seed contains some active compounds, such as amygdalin, sterol and β-sitosterol. Amygdalin is used for medical purposes, mainly as drug in cancer. β-Sitosterol is found in health supplement for various physical ailments. In this work, extraction was conducted at pressure of 20, 30 and 45 MPa, temperature of 40, 60 and 80 °C, and CO₂ flow rate of 3 ml/min for 180 min. Roasted powder and ground unroasted loquat seeds were used as materials. Component in extract was analyzed by HPLC carried out on 5C18-MS column at 27 °C for amygdalin, and 35 °C for β-sitosterol using acetonitrile:water (85:15 v/v) as mobile phase. Based on results, a change in temperature and pressure affected the yield of total extract, amygdalin and β-sitosterol recovery. For comparison between extract from roasted powder and ground unroasted loquat seed, total extract and β-sitosterol recovery from roasted powder loquat seed were higher than that from unroasted one. On the other hand, amygdalin recovery from ground unroasted seed was much higher than that from roasted powder. The optimum condition of extract from roasted powder and ground unroasted loquat seed and amygdalin recovery were obtained at 80 °C and 20 MPa.