Evaluation of scavenging activity assessed by Co(II)/EDTA-induced luminol chemiluminescence and DPPH center dot (2,2-diphenyl-1-picrylhydrazyl) free radical assay

The scavenging activities of three standard antioxidants, quercetin, ascorb ic acid, and trolox, were evaluated by Co(II)/ethylenediaminetetraacetic ac id (EDTA)-induced luminol chemiluminescence and the 2,2-diphenyl-1-picrylhy drazyl (DPPH) free radical assay. Therefore, the aim of this study was to c haracterise an enzyme-free and time-independent chemiluminescence method fo r the assessment of the scavenging profile of compounds in a cell-free syst em using the Co(II)/EDTA-luminol-peroxide system. These results showed that the three standards were efficient and effective in inhibiting both Co(II) /EDTA-induced luminol chemiluminescence and the free radical DPPH. For all the data obtained in this work, the scavenging activity for the standards t ested decreased in the following order: quercetin>trolox> ascorbic acid. Th e present study has applied a simple and precise procedure for the study of hydroxyl radical scavenging activity by Co(II))/EDTA-induced luminol chemi luminescence, and this was assessed by DPPH free radical scavenging. (C) 20 01 Elsevier Science Inc. All rights reserved.