Triacetoneamine-N-OxylSuperoxide DismutaseRiboflavin SynthaseHydrogen PeroxideSuperoxidesScopoletinOxidation-ReductionParaquatFree RadicalsCyclic N-OxidesAldehydesManganeseXanthine OxidaseCatalaseElectron Spin Resonance SpectroscopyKineticsSpin LabelsElectrochemistryFree Radical ScavengersCatalysisSpectrophotometryCopperNADOxygenOxidoreductasesReactive Oxygen SpeciesHydrogen-Ion ConcentrationOxidative StressEscherichia coli