Green chemistry-based sustainable extraction of curcuminoids from turmeric (Curcuma longa L.) using deep eutectic solvents for efficient extraction

A sustainable method for the extraction of curcuminoids from Curcuma longa was developed using natural deep eutectic solvents (NADES). A total 64 NADES combinations were synthesized using choline chloride, organic acids, and polyols, and their physicochemical properties were evaluated. A ternary NADES composed of choline chloride, oxalic acid, and butane-1,4-diol (1:1:2, molar ratio) showed the highest total curcuminoid yield. Further optimization using Box-Behnken design and response surface methodology identified the optimal extraction conditions. The optimal extraction temperature, extraction time, and molar ratio of butane-1,4-diol were 46.8–49.3 °C, 16 min, and 2.7, respectively. Water dilution (50-fold) recovered 82.7–90.9 % of curcuminoids compared with solid-phase extraction. The stability of curcuminoids extracted using NADES was comparable to , or higher than, that obtained with conventional organic solvents. This approach provides an eco-friendly and efficient strategy for curcuminoid extraction, with promising implications for functional food and pharmaceutical applications. • Sixty-four NADESs were synthesized and evaluated for curcuminoid extraction. • Ternary NADES of ChCl, oxalic acid, and butane-1,4-diol achieved the highest yield. • Sigma-profile supported molecular interactions between curcuminoids and NADES. • Anti-Solvent recovery method achieved 82.7–90.9 % curcuminoid recovery using water. • The selected NADES has curcuminoid stability similar to organic solvents.