Study of Antioxidation of Extract from Longan Pericarp

Longan(Euphoria Longan Lam.) pericarp was extracted in turn with n-hexane,ethyl acetate and methyl alcohol for 4 hours in Soxhlet extractor,their extraction rate being 0.58%,1.02% and 2.92%,respectively,the sequence of antioxidative activity in lard was n-hexane extract(Ⅰ)ethyl acetate extract(Ⅱ)methyl alcohol extract(Ⅲ),and antioxidative activity of w(Ⅲ)=0.04% was near to that of w(BHT)=0.02%.By polyamide column chromatography Ⅲ was separated into water eluent(A),C2H5OH(φ=30%) eluent(B),C2H5OH(φ=70%) eluent(C),C2H5OH(φ=95%) eluent(D),methyl alcohol eluent(E),they showed remarkable antioxidative activity,and antioxidative activity of w(B)=0.04%,w(C)=0.04% and w(D)=0.04% were near to that of w(BHT)=0.02% in lard.By colour test,the antioxidative components were preliminary determined as follows:flavone in Ⅱ,C and E,dihydroflavone inⅠand D and phenolic acid in A and B.