COSMO-SAC model approach for deep eutectic solvent selection to extract quercetin from macela (A. satureioides) and experimental process optimization

In this work, deep eutectic solvents (DES) were evaluated like food-grade solvents, combined with an ultrasound-assisted technique for the extraction of quercetin from macela (Achyrocline satureioides). A COSMO-SAC (COSMO-segment activity coefficient) tool was applied to assist the solvent choice. From all evaluated DES, the composition based on choline chloride:glycerol:water (CGH2) was considered the most suitable to extract quercetin and other phenolics. The optimized process conditions by face-centered cubic design were the following: 90 min, 55 degrees C, and 1:100 solid-solvent ratio. According to chromatographic analysis, CGH2 showed high quercetin (27.7 mg/100 g) and catechin (26.1 mg/100 g) extraction capability. The higher quercetin content reinforces the ability of the predictive tools to support the solvent choice. Additionally, phenolic acids, p-coumaric, and Rosmaniric were reported for the first time in the A. satureioides extracts. Finally, was proposed a green and efficiency method to recovery quercetin and other phenolics from macela.