Ferrocyanides: Inorganic salts of the hypothetical acid ferrocyanic acid (H4Fe(CN)6).Ferricyanides: Inorganic salts of the hypothetical acid, H3Fe(CN)6.Toxicodendron: A genus (formerly part of Rhus genus) of shrubs, vines, or trees that yields a highly allergenic oleoresin which causes a severe contact dermatitis (DERMATITIS, TOXICODENDRON). The most toxic species are Toxicodendron vernix (poison sumac), T. diversilobum (poison oak), and T. radicans (poison ivy). T. vernicifera yields a useful varnish from which certain enzymes (laccases) are obtained.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Lactoperoxidase: An enzyme derived from cow's milk. It catalyzes the radioiodination of tyrosine and its derivatives and of peptides containing tyrosine.