The most oxidation numbers of copper in living organisms are Cu(II) and Cu(I). The essential trace element copper is a cofactor of many enzymes involved in redox reactions, such as cytochrome c oxidase, ascorbate oxidase, or superoxide dismutase. In addition to its enzymatic roles, copper is used in biological systems for electron transport (Valko et al., 2005). The blue copper proteins that participate in electron transport include azurin and plastocyanin.
Level of copper can effect to Cancer, Neurological disorders such as Alzheimer‘s disease (AD), and Parkinson‘s disease (PD), Chronic disease: diabetes, cardiovascular disease and atherosclerosis.