Tailoring Natural Solvents: Deep Eutectic Approach for Recovering Bioactives From Prunus spinosa L.

In this study, several choline chloride (ChCl)-based deep eutectic solvent (DES) combinations were prepared at different molar ratios (1/1, 1/2, and 2/1) using amine (urea), polyols (ethylene glycol and glycerol), and carboxylic acids (lactic acid, formic acid, propionic acid, and acetic acid). The performances of the DESs in the homogeniser-assisted extraction of Prunus spinosa L. fresh fruit were compared depending on the total phenolic content (TPC), total anthocyanin content (TAC), and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (antioxidant activity [AA]) yields. Based on the findings of Tukey's test for multiple comparisons, ChCl/formic acid (2/1) provided the best extraction efficiency with statistically significant differences (p < 0.05). Fourier-transform infrared spectroscopy was used to confirm the formation of the proposed DES. Furthermore, the proposed DES also showed better performance compared to conventional aqueous ethanol (60%, v/v) and water. Then, the selected DES (ChCl/formic acid, 2/1) was employed for the optimization study using the Box-Behnken Design of the response surface methodology. The optimum process conditions for the maximum yields of TPC (52.34 mg-GAE/g-FF), TAC (2.09 mg-cyn-3-glu/g-FF), and AA (89.21%) were found to be 50% (v/v) water in the DES, 0.833 g of material, and 69.906 s extraction time.