Green Separation and Extraction of Isofraxidin from Acanthopanax senticosus Using Deep Eutectic Solvent Synthesized from Choline Chloride and Citric Acid

Abstract

Acanthopanax senticosus (Rupr. Maxim.; AS) is a medicinal plant used in the clinical treatment of cerebrovascular diseases and central nervous system disorders, and it significantly improves blood lipid levels and endothelial cell function in patients with acute cerebral infarction. Isofraxidin, one of the active ingredients of AS, is the core of the plant’s medical effects, and its extraction depends on organic solvents. Deep eutectic solvents (DESs) are new green solvents synthesized by intermolecular hydrogen bonding between hydrogen bond donors (HBD) and hydrogen bond acceptors (HBA) which are non-toxic, have a high separation and extraction efficiency, and are environmentally friendly compared to traditional organic solvents. In this paper, DES was used for the extraction of isofraxidin from AS. The primary findings demonstrated that the DES had a viscosity higher than that of ethanol, and even adding a small amount of water (approximately 10%) would trigger solvent redistribution, leading to a considerable reduction in solvent viscosity. In comparison to ethanol, the extraction rate of isofraxidin by DES was 2–3 times higher. Thus, this work developed a new technique for using green extraction of isofraxidin that has some practical implications.