Supercritical CO2 oil extraction from Bauhinia forficata link subsp. pruinosa leaves: Composition, antioxidant activity and mathematical modeling

[Display omitted] •Bauhinia forficata leaf extracts were obtained by Soxhlet and supercritical methods.•The extraction yield increased with the polarity of the solvent.•An increase in pressure improved the extraction yield.•The Sovová model represented well the experimental data. The subspecies B. forficata subsp. pruinosa is practically unexplored scientifically. Thus, the aim of this study was to evaluate a supercritical fluid extraction method and to compare it with the conventional Soxhlet method. The supercritical fluid extraction was performed with CO2, at temperatures of 40–60 °C and pressures of 18–22 MPa, while the Soxhlet method was conducted using ethanol, ethyl acetate and n-hexane as solvents. The extract obtained applying the conventional method with ethanol showed the best results for extraction yield, phenolic and flavonoid contents and antioxidant activity. In the case of the supercritical extraction, the highest yield was obtained at 22 MPa and 60 °C. A mathematical model developed by Sovová was applied to describe the experimental extraction curves and they showed a good fit with the experimental data. The major compounds found in the B. forficata extracts were tocopherols, octacosanol and phytol.