Study on Extraction Flavonoids from the Orange Peel and Antioxidant Activities

The flavonoids were extracted from orange peel,which was controlled with assisted microwave radiation.And the optimal operating parameter was obtained.At the same time,the antioxidant activities of flavonoids from orange peel,hydroxyl radicals(·OH) and superoxide anion(O2-·) were discussed and compared with Vc.The extraction yield of flavonoids from orange peel was determined by the detecting of UV2050 ultraviolet spectrometer and rutin was as the reference substance.Based on the result of single factor experiment,the orthogonal experimental design method was used in order to find the optimal experimental parameters.The optimal experiment parameters are as follows:70%(V∶ V) ethanol as the solvent,the extraction time of 180 min,the extraction temperature of 80℃,the ratio solid / liquid of 1∶ 10 and pH of 7.Under the optimal condition,the flavonoids could reach as high as 86.73 mg / g.The flavonoids from orange peel have the scavenging capacity for hydroxyl radical(·OH) and superoxide anion(O2-·).When the concentration of flavonoids reached as high as 0.18mg/mL,the scavenging capacity of ·OH was 37.72% and the scavenging capacity of O2-· was 28.51% when the concentrations of flavonoids were 0.14 mg / mL.The free radical scavenging capacity of Vc was better than that of flavonoids.