Ultrasonic extraction and purification of scutellarin from Erigerontis Herba using deep eutectic solvent

Nowadays, deep eutectic solvent (DES) was widely used in the extraction of bioactive in traditional Chinese medicine (TCM) as an alternative to organic solvents. While as, it is still a challenge for the removal of DES solvents and recovery of the extracted product. In this study, a simple, efficient and green technique of preparing scutellarin from Erigerontis Herba(EH) was proposed, combining ultrasonic assisted-DES extraction with anti-solvent purification. Firstly, different types of DES were prepared and studied for their abilities to extract scutellarin from EH. DES composed of choline chloride and acetamide (1:4 mol/mol) with 30% water obtained the highest extraction yield. Anti-solvent was proved as an efficient method to recover scutellarin from the DES extract with a content of purification up to 71.2%. Moreover, microscopic structural analysis was carried out to investigate the extract process and explain the extraction principle. Furthermore, the antioxidative activities of the DES extracts were evaluated, indicated that the bioactive property of scutellarin were still remained by using DES as the extraction solvent. In conclusion, the proposed simple and green ultrasonic assisted DES extraction method will serve as an effective alternative strategy to extract bioactive compounds from TCM.