THE FATTY OIL FROM OKRA SEED: SUPERCRITICAL CARBON DIOXIDE EXTRACTION, COMPOSITION AND ANTIOXIDANT ACTIVITY

摘要

Supercritical carbon dioxide extraction (SC-COj of oil from okra (Abelmoschus esculentus L.) seed was performed and compared using screw press expression (SPE) and solvent extraction (SE) methods. Response surface methodology (RSM) was applied to optimize the parameters of SC-C02 extraction. The statistical analysis proved that the quadratics of pressure, the interactions between pressure and CO2flow rate, the linear term of pressure and extraction time, influenced the oil yield to a highly significant level. The optimal extraction condition for oil yield within the experimental range of the variables researched was at 299.08 bar, l4.88L/h, 40.73°C and 93.89 min. At this condition, the yield of oil was predicted to be 17.16%. The okra seed oils yields extracted by SC-CO^ SE and SPE are 17.17%, 18.21% and 15.92%, respectively. There are no significant differences in the compositions of the oils extracted from these three methods. The four main components of all oils are linoleic acid, oleic acid, palmitic acid and stearic acid. The DPPH radical scavenging activity of the oil extracted by SPE is higher than those by SC-CO2 andSE.