Influencing factors in ultrasonic enhanced supercritical fluid extraction for extracting CLSO and CLSE from coix lacryma-jobi seeds

The influencing factors in the ultrasonic enhanced supercritical fluid extraction (USFE) for extracting CLSO and CLSE from coix lacryma-jobi seeds were studied, the factors include temperature, pressure, raw material size, supercritical CO2flow rate, ultrasonic parameters and time-period of the extracting process. As compared with the SFE process (supercritical CO2extraction without ultrasonic enhanced), the results of USFE process show that the optimum extraction temperature of USFE is 40°C, which is 5°C lower than that of SFE, the optimum extraction pressure is 20 MPa, 5 MPa lower than SFE, the optimum extraction time-period is 3.5 hours, 0.5 hours less than SFE. And the extraction yield is increased by about 10% under each optimum condition. To get the same extraction yield, using ultrasonic enhancement the fluid flow rate can be reduced by 0.5 L·h-1and the requirement for the extracted row material size can be relaxed for a bit.