Hydrophilic deep eutectic solvents: A new generation of green and safe extraction systems for bioactive compounds obtaining from natural oil & fats – A review

In the last decade, “green” technologies have emerged as responsible, sustainable, effective, and highly applicable alternatives for obtaining products rich in biologically active substances. With the continuous development of this field, different applications utilizing various natural sources have become worldwide trends. Concurrently, the interest of pharmaceutical, food, and cosmetics industries in bioactive compounds derived from natural sources or in secondary metabolites from specific plants has accelerated the demand for the development of new technologies for their extraction, fractionation, purification and chemical analysis. This demand is accompanied by increasingly stricter requirements for both the quality of the final products and the production process in terms of environmental impact. In the last five years, the number of studies on new extraction processes using deep eutectic solvents have grown exponentially. These solvents have been shown to be not only more affordable and enable quicker extraction but also more ecologically friendly and efficient, with higher yields. Therefore, this study aims to present the use of the most widely applied hydrophilic deep eutectic solvents in recent research work for the extraction of biologically valuable compounds from natural oily materials and to provide a basis for future research on this topic.