Natural Deep Eutectic Solvents for the Extraction of Mulberroside A from White Mulberry Root Bark

In this study, an ultrasonic extraction method of mulberroside A from <i>Morus alba</i> L. based on natural deep eutectic solvents (NADESs) was developed. A total of 24 natural deep eutectic solvents (NADESs) with different formulations were designed to extract <i>M. alba</i> L. powder, and high-performance liquid chromatography (HPLC) was used as the detection method, with the content of mulberroside A as the only evaluation index. The results showed that malic acid:glucose (1:3) contained the highest mulberroside A content of 0.06% with excellent extraction specificity. In addition, the parameters such as water content, extraction temperature, extraction time, and feed/liquid ratio, which have a great influence on NADESs, were optimized, and the antioxidant activity of NADES extracts was tested. Finally, further fine separation of mulberroside A by semidynamic adsorption on porous polymer beads yielded a refined product of mulberroside A under NADES extraction conditions with a purity of 82.9%.