Optimization of Supercritical CO_2 Fluid Extraction Process for Volatile Oil from Angelica sinensis

Objective: To optimize supercritical CO2 fluid extraction process parameters of volatile oil from Angelica sinensis.Method: With composite score of the content of ligustilide and yield of volatile oil as index,the content of ligustilide was determined by HPLC,L9(34) orthogonal test was used to investigate effect of extraction temperature,extraction pressure,extraction time on extraction efficiency.Result: Optimum process parameters were as follows: extraction pressure 30 MPa,extraction temperature 50 ℃,extraction time 2 h,flow rate of CO2 25 L.h-1,pressure of separation kettle I 8 MPa with temperature at 50 ℃,separation pot II pressure of the system tail pressure with temperature at 35 ℃.Conclusion: This optimized process was stable and feasible,which could be adopted to extract volatile oil from A.sinensis with high yield and good quality.