Parametric and kinetic study of supercritical carbon dioxide extraction on sinensetin from Orthosiphon stamineus Benth. leaves

Sinensetin is a rare polymethoxyflavone that possesses strong anti-angiogenesis activity that can be obtained from Orthosiphon stamineus (O. stamineus) leaves. In this study, supercritical carbon dioxide (SC-CO2) extraction was used to improve sinensetin recovery from O. stamineus leaves. The effect of mean particle size (400-550, 550-650 and 650-750 mu m), modifier ratio (0, 5 and 10%, v/v), flow rate (3, 4 and 5 mL/min), temperature (40, 60 and 80 degrees C) and pressure (10, 20 and 30 MPa) on the concentration of sinensetin and determine its extraction rate were investigated. Two models, viz. Patricelli and Peleg were used to evaluate the kinetic behavior of sinensetin in the SC-CO2 system. Results showed that the highest concentration of sinensetin was successfully extracted at 550-650 mu m, 10% (v/v), 5 mL/min, 80 degrees C and 10 MPa. Also, the kinetic profile of sinensetin was well correlated with Patricelli and Peleg models with a low percentage average absolute relative deviation (AARD%) and a high coefficient of determination (R-2) of 0.974, respectively. Thus, the fastest extraction rate of sinensetin was obtained at 9.039 x 10(-3) mg/g min(-1) using the Patricelli model and 8.694 x 10(-3) mg/g min(-1) using the Peleg model at 40 degrees C and 30 MPa.