Process Optimization for Supercritical Carbon Dioxide Extraction of Origanum vulgare L. Essential Oil Based on the Yield, Carvacrol, and Thymol Contents.

Taking the comprehensive score as the index, the interaction between the four independent variables in the supercritical fluid extraction process was evaluated by the response surface method. The effects of extraction parameters on the yield of EOs and the contents of thymol and carvacrol were comprehensively investigated.