Antioxidants are the substances which neutralize the harmful affects of free radicals and protect the cell against the oxidative stress
They are
Superoxide dismutase – present in cytoplasm and produced by mitochondria. It converts super oxide to hydrogen peroxide
Catalase – produced by peroxisomes. It converts hydrogen peroxide to water
Glutathione peroxidase – produced by mitochondria and present in cytoplasm. It converts moreharmful hydroxyl ions into hydrogen peroxide
Vitamin C in cytoplasm
Ferritin and Ceruloplasmin present in cytoplasm – Levels of active forms of iron and copper are minimized by binding of ions to storage and transport proteins like transferrin, ferritin, ceruloplasmin there by minimizing the formation of hydroxyl ion
Vitamins E, A and β Carotene in the plasma membrane and cell membrane of organelles
