Sustainable and Green Engineering Insights on Deep Eutectic Solvents toward the Extraction of Nutraceuticals

Abstract

Deep eutectic solvents (DES) hold promising potential in the selective purification of bioactive molecules from various complex sources. Although they are increasingly considered as a biocompatible extraction medium, adding the task-specific functionality, which makes DES distinctive for the selective extraction of compounds, requires appropriate tailoring of their physical properties. This critical review investigates the influential physical properties of deep eutectic solvents and their effect on various sustainable extraction methods—including both solid–liquid and liquid–liquid—for the separation of nutraceuticals. Various methods by which DES are employed as solvents, cosolvents, or as adjuvants in different extraction systems are compared in terms of their efficiency and selectivity. Furthermore, the correspondence between the type of DES and the nature of target nutraceuticals to be extracted is also discussed. The Review highlights the key achievements and future prospects of employing DES along with the lacunae in the current investigations and proposed various approaches for sustainable applications.