Optimizing deep eutectic solvents to extract nicotine by response surface methodology

In order to develop a green nicotine extraction method, deep eutectic solvents (DES) were studied using flue-cured tobacco leaves as extraction materials, and four extraction factors (moisture content in DES, extraction time, extraction temperature and solid/liquid ratio) were optimized via single-factor experiments to produce a response surface based on nicotine yields. The results showed that:1) The optimum deep eutectic solvent was choline chloride-urea. 2) The optimized treatment condition was achieved with the DES moisture content at 32% (V/V), extracting for 30 minutes at 40℃ with the solid/liquid ratio of 10 mg/mL. The calculated extraction yield of nicotine was 22.72 mg/g, and the measured yield was 22.89 mg/g. In summary, the optimized extraction condition is reliable, and could be used as a reference for the green extraction of nicotine in tobacco leaves.