Study on extraction and antioxidative activity of flavonoids in the peel of pitaya

Objective:To provide the theoretical basis for the development and utilization of flavonoids from the peel of pitaya(PPF).Method:Using ethanol as the extraction solvent,crude flavonoids was extracted.The optimum extraction conditions of total flavonoids were determined by single factor experiments and orthogonal test,the antioxidation activity of flavonoids of peel of pitaya was investigated through comparing the eliminating effect to the free-radical of VC and BHT in vitro.Result:Optimum extraction conditions were as follows:the ethanol concentration was 80%,the extraction liquid-material ratio was 1∶ 30,the extraction temperature was 80℃ and the extraction time was 0.5h.Under optimum extraction conditions for twice extraction,the yield rates of the total extraction rates of flavonoids in the dry powder of the peel of hylocereus andatus were 10.9 mg/g.Results:The flavonoids extracted from the peel of pitaya had strong scavenging ability on removing superoxide radicals and hydroxyl radicals,and strong reducing power at the same conditions.Conclusion:Flavonoids of the peel of pitaya had strong antioxidative capabilities in vitro and had potential as a natural antioxidant.