Optimization of Supercritical Fluid E xtraction Technology and GC-MS Analysis of Volatile Oil from Clematis chinensis

Objective:To optimize supercritical carbon dioxide fluid extraction(SFE-CO2) process of volatile oil from the roots of Clematis chinensis,and components of volatile oil were analyzed by GC-MS.Method:With yield of volatile oil as index,effects of extraction time,particle size of raw materials,fluid extraction pressure and temperature on SFE-CO2 process of volatile oil from the roots of C.chinensis were investigated by single factor test and orthogonal test,and chemical constituents of volatile oil were analyzed by GC-MS.Result:Effects of three factors on yield of volatile oil were in order of extraction pressureextraction timeextraction temperature;Optimal fluid extraction technology was as following:extraction pressure 20 MPa,extraction time 1.5 h,temperature 45 ℃;Yield of volatile oil under these conditions was 0.44%.156 compounds were identified by GC-MS and they were accounting for 85.03% of the total content of volatile oil,compositions that the relative content was more than 1% accounted for 51.78% of the total content of volatile oil.Conclusion:SFE-CO2 method had higher extraction efficiency than steam distillation,this optimized technology was stable and reliable.In addition,chemical compositions of volatile oil were complicated,and protoanemonin,the major bioactive component in volatile oil from the roots of C.chinensis,was found by GC-MS for the first time.