Study On The Extraction And Purification Process Of Cichoric Acid In Echinacea Purpurea

Among caffeic acid derivatives in Echinacea Purpurea, cichoirc acid has been shown to inhibit hyaluronidase and HIV-1 integrase, and to possess phagocytosis stimulatory activity in vitro and in vivo and antiviral acitivy. This paper is mainly concerned with the study on the extraction and purification process of cichoric acid in Echinacea Purpurea. The procedure to analyze cichoric acid with HPLC was set up. The contents of cichoric acid in introducing plant of Echinacea purpurea in china were assayed by HPLC. Results show that there is cichoric acid in every part of Echinacea purpurea and cichoric acid content in stems is generally low and content in leaves is highest.The optimal extracting condition was obtained. The crude product was obtained with a content of 4.1% and a yield of 0.8527% at the condition of that the raw materials was extracted three times for 2 h at 90℃ with 40% ethanol and the ratio (solvent: raw materials) of 15:1.The purification process was investigated and different kinds of products (20%,40%,60%,above 90% in content) were obtained by the means of adsorption and desorption with AB-8 resin, extraction by organic solvent and crystallization.The technology conditions for adsorbing and separating cichoric acid with AB-8 resin were as follows: the concentration of sample of Echinacea purpurea extract ,3～4mg/mL; pH, 3; the current velocity of adsorption, 4BV/h; the eluting regent, 30% ethanol(6 folds the volume of the resin); eluting velocity, 2BV/h. The maximum adsorbing capacity of AB-8 resin for cichoric acid was 18.0 mg/mL, with the yield of 90.2%. Through adsorption and separation of AB-8 resin, the product was obtained with a content of 20.2%. The content of powder increased to 40% with the yield of 93.9% by the means of extraction with ethyl acetate for 3 times. Subsequently, the shallow yellow product was obtained by extraction with aether for 4 times and the yield was 96.9%. The total yield of these three processes was above 80%. The final product could be obtained by crystallization and recrystallization with hot water. The contents of the crystals were 91.1% and 95.9% and the yield were 71.3% and 82% respectively.The content of product can increased to 40% by direct extraction for 3 times with ethyl acetate and successive extraction for 4 times with aether from sample solution of Echinacea purpurea extract(pH3).The polyphenol oxidase which is responsible for the degradation of cichoric acid in Echinacea Purpurea was also studied. Enzyme activity is highest at 40℃, pH 7.0. PPO can be inhibited by heating and adding of inhibitors such as Vc,NaHSO3,citric acid.