Extraction technology of the volatile oils from Artemi- siae argyi Leaves by supercritical CO_2 and microwave

In the paper,the volatile oils from the leaves of Artemisia argyi were obtained with supercritical CO 2 and microwave for their optimum extraction conditions. The uniform design experiment were used to optimize the SFE CO 2 conditions,and the optimal conditions were determined:the pressure of 16MPa,the temperature at 31 ℃,CO 2 flowing rate at 20 kg/h and the time for 80 min. The optimum conditions of the microwave extraction were obtained by orthogonal experiment: radiation time for 200 s,microwave power of 720 w,400 mL solvent,40 mL washing solvent. The volatile oils were obtained by supercritical CO 2,microwave and steam distillation,extraction rate were 3.75%,4.85% and 1.87% respectively. The results showed that the extraction rate of microwave extraction was the highest and its process was simpler,but its quality was worse than the volatile oils extracted by supercritical CO 2 and steam distillation which qualities were better.