Extraction of Synadenium grantii Hook f. using conventional solvents and supercritical CO2 + ethanol

Abstract

Synadenium grantii extracts were obtained by employing two different extraction techniques: supercritical CO2 with ethanol as solvent (scCO2+EtOH) and Soxhlet with different solvents. Extractions were evaluated according to antioxidant capacity, extract compositions, and overall extraction yields, which increased with solvent polarity. For Soxhlet extractions, the highest extraction yield was obtained with water as the solvent and the lowest with hexane. In extraction using scCO2+EtOH, the addition of ethanol increased the extraction yield and kinetic parameters due to the increase in solvent polarity. The IC50 result demonstrated that extracts obtained with polar solvents presented higher antioxidant capacity in comparison to non-polar solvents. For scCO2+EtOH extractions, the result with higher antioxidant capacity was obtained using ethanol to solids mass ratio of 1:1. The most important compounds identified in S. grantii extracts by mass spectrometry were euphol, carvacrol, betulin aldehyde, and friedelan-3-one, which have great potential applications in cosmetics, pharmaceuticals, and food industries.