Deep eutectic solvent as a green solvent for enhanced extraction of narirutin, naringin, hesperidin and neohesperidin from Aurantii Fructus

Introduction In the present study, a green and efficient extraction method using deep eutectic solvents as extraction solvent was developed for extracting the four major active compounds narirutin, naringin, hesperidin and neohesperidin from Aurantii Fructus. Methodology A series of tunable deep eutectic solvents were prepared and investigated by mixing choline chloride or betaine to different hydrogen-bond donors, and betaine/ethanediol was found to be the most suitable extraction solvent. To achieve the best extraction yield, the primary factors affecting the extraction efficiency, such as hydrogen-bond acceptor/hydrogen-bond donor ratio, water content in deep eutectic solvents, extraction temperature, solid/liquid ratio and extraction time, were investigated. Results The optimal extraction conditions were 40% of water in betaine/ethanediol (1:4) at 60 degrees C for heated extraction of 30 min and solid/liquid ratio 1:100 g/mL. Under the optimum extraction condition, the extraction yields of narirutin, naringin, hesperidin, and neohesperidin were 8.39 +/- 0.61, 83.98 +/- 1.92, 3.03 +/- 0.35 and 35.94 +/- 0.63 mg/g, respectively, which were much higher than those of methanol as extraction solvent (5.5 +/- 0.48, 64.23 +/- 1.51, 2.16 +/- 0.15 and 30.14 +/- 0.62 mg/g). Conclusion The present results showed that deep eutectic solvents could be promising green and efficient solvents for extraction of the bioactive ingredients from traditional Chinese medicine.