Application of deep eutectic solvents in the extraction of anthocyanins: Stability, bioavailability, and antioxidant property

Anthocyanins have gained significant attention in the food industry due to their various health-promoting benefits and diverse colors. However, their low bioavailability and susceptibility to environmental conditions pose challenges to their integration into food systems While distilled water and aqueous solutions of ethanol and methanol are commonly used solvents for this purpose, there have been considerable efforts to develop green solvents that can address some of the drawbacks associated with conventional solvents, such as toxicity, volatility, and flammability. As a solution, deep eutectic solvents (DESs) and natural deep eutectic solvents (NADESs) have been introduced as novel green solvents. Here, we reviewed the properties of the eutectic solvent used for anthocyanin extraction and how they affect anthocyanin stability is deeply considered. The extraction efficiency of anthocyanins using DESs compared to conventional solvents has been studied. In addition, the effects of this type of solvent on bioavailability, and antioxidant activity were presented. Using green solvents such as DESs and NADES which improve the extraction efficiency of anthocyanins, their stability, bioavailability, and antioxidant activity, which has highlighted them as more suitable solvents compared to organic solvents. Among different eutectic solvents, choline chloride-oxalic acid NADES is the most efficient solvent for the extraction of anthocyanins. Moreover, organic acid-based eutectic solvents are better extractants for polar anthocyanins than other solvents. Difficult separation of target compounds is one of the challenges of using these solvents, which can be solved with recovery techniques.