Peroxide - substances, which include peroxide group containing a single covalent bond " between the two neighboring atoms of oxygen. Hydrogen peroxide H2O2 - the most important representative of peroxides is obtained in the processing of peroxides of sodium (Na2O2) or of peroxide of barium (HLW2) sulfuric acid. H2O2 - colourless, syrupy liquid. Being a strong oxidizer, H2O2 finds application in medicine (see Peroxide). In the body of H2O2 is formed by some of oxidative reactions, usually catalyzed by enzymes-flavoprotein: EN2 + O2 = A+H2O2, where an2 - oxidizable substrate. Formed H2O2 immediately decomposes very active enzyme catalase: 2H2O2=2H2O+O2. In addition to H2O2, known group of inorganic P. (nadkislot and their salts), for example nadmerna acid H2S2O8. To organic peroxides include, for example, P. fatty acids produced during the oxidation of unsaturated fatty acids by lipotoxicity.