A new green alternative solvent for extracting echinacoside and acteoside from Cistanche deserticola based on ternary natural deep eutectic solvent

Echinacoside and acteoside, the representative constituents of Cistanche deserticola Y. C. Ma (C. deserticola), are known for its many important biological activities. In this study, a novel ternary natural deep eutectic solvent (NADES) (citric acid, fructose and glucose in a 1:2:1 molar ratio, 30 % water content) was obtained through the adjustment and optimization of single-factor experiments. And through the Box-Behnken design optimization, the optimal extraction conditions were obtained, at the moment, the yields of echinacoside and acteoside were 6.16 and 2.13 mg/g, respectively. In addition, through computer molecular simulation, it was found that there are strong hydrogen bonds and interactions between the molecules of NADES, and the hydrogen bonds, van der Waals forces and π-π interactions played an important role in the extraction of echinacoside and acteoside from C. deserticola by NADES. Finally, compared with the traditional method, NADES ultrasound-assisted extraction of echinacoside and acteoside has a shorter time (15 min), the maximum extraction yield is 1.54–2.86 times and 1.26–2.52 times than that of traditional extraction methods for echinacoside and acteoside, respectively. This study demonstrates that NADES can provides a new direction for developing new sustainable alternatives, improving green extraction process and efficiency for extracting natural active substances.