Optimization of Technology for Supercritical CO₂ Extraction of Total Flavones from Viola Yedoensis Makino by Response Surface Method

OBJECTIVE To optimize the conditions for the extraction of total flavones from Viola yedoensis Makino by supercritical CO₂ extraction. METHODS The content of total flavones was determined by UV-Vis. The extraction yield of total flavones was used as index and the extraction conditions was optimized by response surface method(RSM). RESULTS The optimum extraction conditions were obtained as follows: extraction pressure 35 MPa, extraction temperature 54 ℃, the volumes of entrainer 0.48 mL·min^-1, ethanol concentration 80%, extraction time 120 min. Under this condition, the actual extraction rate was 5.89%. The extraction pressure and temperature had a great influence on the extraction yield. CONCLUSION The total flavones extraction rate with supercritical carbon dioxide from Viola yedoensis Makino is high, and this method is less solvent consumption, simple and feasible.