Generation and Detoxication of Reactive Oxygen Species

Metabolic pathways such as the electron transport chain of mitochondrial respiration and biochemical reduction of oxygen by enzymes of xenobiotic metabolism, 

Antioxidant compounds are an important defense for immediate detoxication of highly reactive intermediates. They act as competing nucleophiles and can bind to the intermediate, forming a less reactive species. Glutathione is one antioxidant molecule that can directly interact with free radicals. Other chemical antioxidants include vitamins A (retinol), C (ascorbic acid), and E. Ascorbic acid, for example, may react directly with reactive intermediates by hydrogen abstraction, resulting in the formation of dehydroascorbic acid. 

Production of reactive metabolites, reactive oxygen species 

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