Modeling of supercritical fluid extraction of flavonoids from Calycopteris floribunda leaves

The aim of this study was to obtain flavonoids extracts from Calycopteris floribunda leaves using supercritical fluid extraction (SFE) with CO₂ and a co-solvent. Pachypodol, a potential anticancer drug lead compound separated from the extracts, was examined. Classical organic solvent extraction (CE) with ethanol was performed to evaluate the high pressure method. HPLC analysis was introduced to interpret the differences between SFE and CE extracts in terms of antioxidant activity and the concentration of pachypodol. SFE kinetics and mathematical modeling of the overall extraction curves (OEC) were investigated. Evaluation of the models against experimental data showed that the Sovová model performs the best. The supercritical fluid extraction process was optimized using a central composite design (CCD), where temperature and pressure were adjusted. The optimal conditions of SFE were: pressure of 30 MPa and temperature of 35°C.