Extraction of limonoids using micro bubble supercritical carbon dioxide

A new technique of supercritical carbon dioxide (SC-CO2) treatment, micro bubble SC-CO2 method, was applied to extraction of limonoids. This method could increase the concentration of SC-CO2 in sample solutions rapidly, so that limonoids were extracted effectively compared with conventional technique. Juice (sample A) and seed extract (sample B) of Natsudaidai were treated at 25 MPa, 35 degrees C. The flow rate of CO2 was 4 g/min. The yield of limonoids was significantly higher than those extracted by conventional SC-CO2 method. When the extraction was carried out for 30 min, the extraction yield of limonoids in sample A and sample B were 92.5% and 42.4%, respectively. When methanol was added as an entrainer, the yield of sample B was increased up to 73.2%.