Ionic Liquid‐Assisted Extraction and Isolation of Cynaropicrin and Cnicin from Artichoke and Blessed thistle

Abstract The sesquiterpene lactones cynaropicrin and cnicin are isolated from artichoke ( Cynara scolymus ) and blessed thistle ( Cnicus benedictus ), respectively. These natural products exhibit several biological activities, including inhibitory activity against Trypanosoma brucei , which causes human African trypanosomiasis (HAT; sleeping sickness). The present study describes a novel ionic liquid‐assisted plant extraction and isolation method for cynaropicrin and cnicin using centrifugation and decantation techniques. The results showed that the extraction yield of cynaropicrin and cnicin using 1‐ethyl‐3‐methylimidazolium methylphosphonate ([C 2 mim][(MeO)(H)PO 2 ])/acetone (1:1) was 1.9 and 1.4 times higher than that obtained using only acetone, respectively. The proposed extraction and isolation method will enable the acquisition of other natural products from medicinal plants.