Determination of cichoric acid content in dried press juice of purple coneflower (Echinacea purpurea) with capillary electrophoresis.

Purple coneflower (Echinacea purpurea) is an immunostimulating drug, containing multiple substances. The most important in activity are polysaccharides, caffeic acid derivatives (cichoric acid), alkamides and glycoproteins. It is not clear yet, which substances are responsible for activity. Cichoric acid is an appropriate marker of the quality of E. purpurea containing product, because it has immune stimulatory effects and it is susceptible to degradation. In this work, an improved capillary electrophoresis method for determining cichoric acid in dried press juice from purple coneflower was developed. The optimal conditions were: electrophoretic buffer-75mM borate, pH 8.8; injection 20mbar for 20s; separation at 20kV; detection at 350nm, temperature 35 degrees C.