Copaíba (Copaifera sp.) leaf extracts obtained by CO2 supercritical fluid extraction: Isotherms of global yield, kinetics data, antioxidant activity and neuroprotective effects

Abstract Copaiba ( Copaifera sp.) is a tree with a wide application in Brazilian folk medicine. The copaiba leaf extract obtained using supercritical CO 2 might be applied to afford neuroprotection following experimental stroke. This study aimed to obtain leaf extracts of Copaifera sp. via supercritical fluid extraction, assessing the global yield isotherms, process variables through the kinetic parameters of extraction, as well as antioxidant activity and neuroprotective effects. Three isotherms (40 °C, 50 °C and 60 °C) were studied in the pressure range of 10–30 MPa. The overall higher mass on dry basis yield (∼3.8%) and antioxidant activity (∼64%) were observed at 20 MPa and 60 °C. For the kinetic study of extraction, the extracts obtained with higher and lower antioxidant activity were chosen, and the models of Martinez et al., Tan and Liou and Sovova showed good and similar adjustments, as presented values of residual sum of squares in the order 10 −2 . The results of histological and immunohistochemical analyzes suggest that the extract obtained at 60 °C and 20 MPa has anti-inflammatory and neuroprotective effects on experimental stroke induced by microinjections of endothelin-1 (ET-1) into the rat brain.