OXIDANTS
Molecular oxygen caLn be reduced to water. The intermuediate steps of' oxygen reductioni arIc
the fiormation of- the superoxide anion radical, hlydr-ogeni percoxide and the hydroxyl radical,
corresponding to the steps of' reduction by one, tNAxo and three clectr-ons, respectively. Further,
ground-st.ate molecul.ar (triplet) oxygen1, as a diradical, can be electronlically excited to singlet
moleculaLr oxygxen. Oxygen radicals Can occur a"Is alkyl or peroxyl radicals, e.g. in lipids. Also,
there is nitric oxide, onCe of' the gasseous radicals of- biological inter-est. Pc-oxyinitr-ite, a noniradical
reactixVe spclies, is f{ormlcd fromii the nitr-ic oxidc aind superoxide alnion radicals.