Solvent effect on the extraction of soluble solids from murici and pequi seeds

Abstract

The Brazilian cerrado has native species with great potential for use, like murici (Byrsonima crassifolia), and pequi (Caryocar brasiliense Camb). The seeds of these fruits are rich in oils and bioactive compounds. The extraction by solvent is widely used to extract oils from the seeds, being hexane the most used solvent in this process. The objective of this work was to evaluate the effect of alternative solvents on oil/soluble solids extraction efficiency and raffinate retention index of solvent extraction of pequi and murici seeds and thermodynamics parameters of the process, using organic green solvents (ethanol, isopropanol, and acetone) and hexane. The extraction has been performed in a shaker using three different temperatures (35, 45, and 55 °C) at the seed:solvent mass ratio of 1:5 (wt/wt). In the extraction with pure solvents the most efficient solvent for both seeds was hexane, at 55 °C, once greater yield and lower retention index were obtained for this condition, along with isopropanol, for pequi seeds. The thermodynamic analysis of the extraction process for both seeds demonstrated positive results to ΔH, and ΔS, and negative results to ΔG, showing the endothermic nature of the process and its spontaneity.