Abstract: BACKGROUND AND AIM: To investigate the free radical scavenging and antilipoperoxidant activities of Maydis stigma extract and their dose-response relationship. MATERIALS AND METHODS: Sprague-Dawley rats were killed and the livers were removed to isolate the microsome by differential centrifugation. The ethanol extract of Maydis stigma were obtained by recirculating. We investigated the effects of the ethanol extract of Maydis stigma (MSE) on luminol-enhanced chemiluminescence of superoxide/hydroxyl radical scavenging properties in cell free system. We also measured malondialdehyde (MDA) from the microsomal suspension and studied the relationship between the lipid peroxidation and the antioxidant metabolism of MSE in rat liver microsomes. RESULTS: MSE possessed very high radical scavenging activity in both chemiluminescence assays. Furthermore, the extract exhibited a significant concentration-dependent inhibition of lipid peroxidation in rat liver microsomes induced by Fe2＋/ascorbate, cumene hydroperoxide (CHP), and NADP＋/CCl4. CONCLUSION: The data clearly demonstrated the free radical scavenging and antilipoperoxidant properties of MSE supporting its reported biological activities.

Key words: Maydis stigma, antioxidative, lipid peroxidation, free radicals, chemiluminescence