Extraction optimization, biological activities, and application in O/W emulsion of deep eutectic solvents-based phenolic extracts from olive pomace.

This study evaluated the phenolic compound extraction from olive pomace with deep eutectic solvents (DES) prepared with choline chloride ([Ch]Cl) and four (poly-)carboxylic acids. Temperature, water addition in the solvent, and solid-liquid ratio were evaluate in total phenolic content and antioxidant activity of extracts obtained with DES and ethanol, as control. Moreover, the antimicrobial activities of solvents and extracts were evaluated. Oil-in-water emulsion with DES extract was prepared, characterized and its oxidative stability analyzed. The extract with the highest total phenolic content was obtained with [Ch]Cl:malonic acid. Under optimal conditions, DES extracted 9 % more total phenolic content than ethanol. DES extract showed superior antibacterial activity to the ethanolic extract, and its presence in oil-in-water emulsion increased the induction time in 10-fold when compared to the one prepared with water. These results reinforce that DES are a potential solvent for phenolic compound extraction from olive pomace with antibacterial and technological benefits.

LLE experimental data, thermodynamic modeling and sensitivity analysis in the ethyl biodiesel from macauba pulp oil settling step.

The aim of this study was to obtain experimental data related to liquid­liquid equilibrium (LLE) of systems containing glycerol + ethanol + ethyl biodiesel from macauba pulp oil, perform thermodynamic modeling and simulate the settling step of this biodiesel using simulation software. Binary interaction parameters were adjusted for NRTL and UNIQUAC models. The UNIFAC-LLE and UNIFAC-Dortmund models were used to predict the LLE of the systems. A sensitivity analysis was applied to the settling step to describe the composition of the output streams as a function of ethanol in the feed stream. Ethanol had greater affinity for the glycerol-rich phase. The deviations between experimental data and calculated values were 0.44%, 1.07%, 3.52% and 2.82%, respectively, using the NRTL, UNIQUAC, UNIFAC-LLE and UNIFAC-Dortmund models. Excess ethanol in the feed stream causes losses of ethyl ester in the glycerol-rich stream and high concentration of glycerol in the ester-rich stream.