Peroxynitrite: a potential initiator of lipid oxidation in food

Peroxynitrite is formed from the nearly diffusion limited reaction between nitric oxide and superoxide. This reactive nitrogen species has received intense interest in the biomedical field as an initiator of potentially harmful oxidation reactions. Peroxynitrite can also be viewed as an important pro-oxidant that affects food quality. Since most biological tissues used for foods contain systems that produce both nitric oxide and superoxide, conditions that enhance or suppress the formation of these precursors will influence the formation of peroxynitrite. The complex oxidative chemistry of peroxynitrite involves direct reactions with cellular constituents such as antioxidants, production of reactive species capable of initiating lipid oxidation, and catalyst-dependent nitration reactions which may redirect the reactivity of peroxynitrite to favor protein oxidations. Thus, peroxynitrite reactions in food may be deleterious, leading to a decline of quality parameters such as flavor, color, and functional properties. (C) 2002 Elsevier Science Ltd. All rights reserved.