Emerging application of extraction phase of ionic and non-ionic deep eutectic solvents toward natural herbal medicine

The concept of sustainable development has affected the perception, process, and methods of extraction process. In that sense, replacing traditional organic solvents with eco-friendly solvents is of utmost importance. The extraction and separation of bioactive compounds from natural herbal medicine using DESs has attracted significant interest in industry and academia. This review summarizes the efforts dedicated to the applying ionic and non-ionic DESs to extract bioactive compounds from natural herbal medicine over the last five years. It also demonstrated the differences in the extraction ability of ionic and non-ionic DESs for different types of active components from natural herbal medicine. The toxicity of DESs is summarized to determine the sustainable of DESs as green solvents. Furthermore, this review presents some critical analysis to determine if using DESs as extraction solvents is sufficient for greening an extraction methodology.