| 摘要: | Four different isolation techniques, the ultrasound-assisted supercritical CO2 (UscCO(2)) extraction, traditional supercritical CO2 (TscCO(2)) extraction, steam distillation (STD) and heat-reflux extraction (HRE), were utilized to isolate volatile oils from the purple leaves of P. frutescens. The highest yield of volatile oils obtained by the UscCO(2) procedure was 1.62% (weight of extracted oil/dry weight of plant material), which was 13.7, 30.2 and 72.2% higher than the oil yields obtained by TscCO(2) extraction, STD and HRE, respectively. In addition, the content of perillaldehyde (49.76%, w/w) obtained by the UscCO(2) process was approximately 1.09, 1.43 and 1.23 times higher than the contents obtained by STD, HRE and TscCO(2) extraction, respectively. Moreover, the theoretical solubility of volatile oils in supercritical solvent was evaluated with the dynamic extraction method and then correlated with the Chrastil, Bartle and Kumar and Johnston models, with average absolute relative deviations (AARDs) of 0.71%, 0.74% and 3.56%, respectively. |
