Green Extraction of Antioxidants from Natural Sources with Natural Deep Eutectic Solvents

Natural deep eutectic solvents (NADES) have been developed in order to replace traditional volatile and toxic organic solvents for the extraction of biologically active substances from natural sources. Recent research has shown that NADES are able to retain and even improve the antioxidant properties of the molecules dissolved in them. The aim of the present study was to evaluate the antioxidant activity of the extracts of two medicinal plants, Plantago major and Sideritis scardica, and of propolis with 10 different NADES. The results obtained confirm that NADES extracts of medicinal plants and propolis have a good antioxidant potential, allowing obtaining natural antioxidants without the application of organic solvents. Because of the biocompatibility and low toxicity of the NADES, the opportunity to apply these extracts directly in formulations, such as cosmetics, food supplements, etc., seems promising.