Application of the natural deep eutectic solvent choline chloride-sorbitol to extract chlorogenic acid and caffeine from green coffee beans (Coffea canephora)

This study aimed to determine the optimum method for extracting caffeine and chlorogenic acid (CGA) from greencoffee beans (GCB) of Coffea canephora using choline chloride–sorbitol, a natural deep eutectic solvent (NADES).Three different preparations of choline chloride–sorbitol and choline chloride–sorbitol–urea (2:1, 4:1, and 6:1) wereused for the extraction. The most effective preparation was used to evaluate the effect of dilution with water andextraction time. Reverse-phase high-performance liquid chromatography, with a gradient solvent system of 0.1%acetic acid (90%) and acetonitrile (10%), was used to quantify the CGA and caffeine. Choline chloride–sorbitol ata ratio of 4:1 was the most effective for extracting chlorogenic and caffeine, with caffeine and CGA yield of 4.49and 16.59 mg/g dry weight, respectively. The optimum water concentration was not found. Using a higher NADESdilution for extraction corresponded to an increased yield of caffeine and CGA. The effective time for extraction wasfound to be 30 minutes, which yielded the most caffeine and CGA. Based on these results, choline chloride–sorbitolcould be an alternative green solvent for extracting caffeine and CGA from C. canephora GCB.

Optimization of ionic liquid-based microwave-assisted extraction of polyphenolic content from Peperomia pellucida (L) kunth using response surface methodology

Objective To optimize the ionic liquid based microwave-assisted extraction (IL-MAE) of polyphenolic content from Peperomia pellucida (L) Kunth. Methods The IL-MAE factors as experimental design parameters, including microwave power, extraction time, ionic liquid concentration, and liquid–solid ratio had been involved. Response surface methodology and Box–Behnken design were used to obtain predictive model (multivariate quadratic regression equation) and optimization of the extraction process. The response surface was analyzed by using the yields of total polyphenolic content as response value. Results Based on the obtained results the optimum extraction condition, including microwave power of 30% Watts, extraction time of 18.5 min, the ionic liquid concentration of 0.79 mol/L, and the liquid–solid ratio of 10.72 mL/g 1-Buthyl-3-methylimidazolium tetrafluoroborate ([bmim]BF