The determination of the caffeic acid derivatives of Echinacea purpurea aerial parts under various extraction conditions by supercritical fluid extraction (SFE)

The effects of various process conditions on the extraction of caffeic acid derivatives (CADs) from the aerial parts of Echinacea purpurea specimens grown in Turkey through supercritical fluid extraction (SFE) and two conventional techniques (ultrasound and shaker) were determined by LC-MS/MS. The concentrations of caftaric acid, cichoric acid, chlorogenic acid, cynarin, and echinacoside were measured. Three extraction variables, i.e., the extraction pressure (EP; 100, 200, and 300 bar), the extraction temperature (ET; 40,50, and 60 degrees C), and the amount of MeOH used as co-solvent (CL; 0%, 5%, and 10%, m/m), were investigated. The ultrasound-assisted extraction exerted more influence on the CADs concentrations than the shaker extraction. Moreover, the effects of the EP*ET and the EP*CL interactions on the SFE extract yield (0.09-0.87%, m/m) and the effect of EP*ET*CL interaction on the individual and total CADs concentrations were identified (p < 0.05). (C) 2014 Elsevier B.V. All rights reserved.