Study On The Extraction, Purification And Anti-oxidation Ability Of Chalcones From The Leaves Of Angelica Keiskei

Angelica Keiskei chalcones is a kind of effective substance could be used supplementarily to cure diabetics. In this paper, the extraction technology of chalcones from the leaves of Angelica keiskei(LAK) assisted by microwave power was studied. The effect of ethanol concentration, ratio of ethonal volum to LAK weight, extraction time and extraction times on extraction were studied respectively. The anti-oxidation ability of the LAK extract was measured according to the scavenging ability of hydroxyl (·OH) radicals and 2, 2-diphenyl-l-picrylhydrazyl (DPPH) radicals. The effects of adsorption time, concentration of LAK extract, pH value of sample solution, desorption time, concentration and pH value of the strippant on batch purification with HZ-806 macroporous resins were studied. The effects of sample concentration, flow rate of sample solution, the concentration of the strippant and flow rate of strippant on continuous purification with HZ-806 resins were also investigated. The main conclusions were as follows:1) The microwave-assisted extraction from LAK was obtained. Proper conditions were as follows:at the power of 320W, ratio of ethanol volume to LAK weight was 40:1, the ethanol concentration was 70%(V/V), the extraction time was 2 minutes and extracted 3 times. Under those conditions the content of chalcones from LAK extract was 1.04%.2) LAK extract had good scavenging abilities on·OH and DPPH radicals and the scavenging percentages of the two radicals were increased with the concentration of LAK extract. The scavenging percentage of hydroxyl radical was 87.04% and DPPH radical was 89.84% when the LAK concentration was 10mg/mL.3) The batch purification process by HZ-806 macroporous resins was obtained. The proper adsorption conditions were as follows:the temperature was 25℃, the wet weight of HZ-806 resins is 0.5g, the concentration of LAK extract was 1000μg/mL and the pH value of sample solution was 4 and the adsorption time was 3 hours. Proper desorption conditions were as follows:the strippant was 70%(V/V)ethanol and the pH value of strippant was 4 and the desorption time was 3 hours at 30℃. Under those conditions the content of chalcones in the purified product was 6.52%. The isothermal adsorption could be characterized well by both the Langmuir equation and the Freundlich equation.4) The continuous purification process by HZ-806 macroporous resins was obtained. The radium of the bed was 3.07cm, the height was 5cm and the bed volumn(BV) was 37mL.Proper conditions were as follows:the room temperature was 25℃, the sample concentration was 1000μg/mL, the flow rate of sample solution was 2BV/h, the strippant was 70% ethanol and the desorption rate was 2BV/h. Under those conditions the content of chalcones in the purified product was 10.82%.The results obtained in this paper provide good foundation to the production and application of chalcones.