Advances in the Extraction of Active Ingredients from Traditional Chinese Medicine Using Deep Eutectic Solvents

Abstract

Deep eutectic solvents (DES), a class of novel green solvents, offer a promising alternative for the extraction of bioactive compounds from traditional Chinese medicinal herbs, addressing both environmental and efficiency limitations associated with conventional organic solvents. Their advantages include straightforward synthesis, low toxicity, biodegradability, and tunable physicochemical properties. This article systematically summarizes recent advances in the application of DES for extracting various active ingredients of traditional Chinese medicine, including flavonoids, saponins, alkaloids, polysaccharides, polyphenols, and volatile oils. It focuses on analyzing the structural characteristics of these compound classes and the underlying principles guiding DES selection, categorizes DES systems suitable for each class of active ingredient, and outlines the corresponding optimized process conditions. Building upon this foundation, the extraction mechanisms—particularly hydrogen bonding interactions and polarity matching between DES and target components—were investigated, and the influencing factors and underlying patterns governing DES extraction efficiency were systematically summarized. In response to current research challenges—including high viscosity, difficult separation and recovery, and the absence of a targeted design theory—future research directions were proposed to support the continued advancement of green extraction processes for traditional Chinese medicine.