SIMPLE DETERMINATION OF PEROXYL RADICAL-TRAPPING CAPACITY

A simple spectrophotometric method of determination of peroxyl radical -trapping capacity (PRTC) of body fluids and food products is proposed . In this method, decomposition of 2,2'-azobis(2-amidopropane) hydroch loride (ABAP) is the source of peroxyl and alkoxyl radicals which oxid ize 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) to a green cation radical. Antioxidant present in a sample inhibit the reac tion; the induction time of the reaction is proposed as a parameter en abling determination of antioxidant content. Standard assay conditions are: 20 mM ABAP and 150 mu M ABTS in 0.1 M phosphate buffer, pH 7.0, at 37 degrees C; absorbance is monitored at 414 nm. A 10-min assay all ows for determination of the induction time of appropriately diluted s ample. As examples of application of this method, PRTC values of sever al types of beverages are reported.