Auto Oxidation Kinetics of Ascorbate by Cupric Ions

• Autores: Troncoso, Luzmila, Guija, Emilio
• Formato: artículo
• Fecha de Publicación: 1998
• Institución: Universidad Nacional Mayor de San Marcos
• Repositorio: Revistas - Universidad Nacional Mayor de San Marcos
• Lenguaje: español
• OAI Identifier: oai:ojs.csi.unmsm:article/4632
• Enlace del recurso: https://revistasinvestigacion.unmsm.edu.pe/index.php/anales/article/view/4632
• Nivel de acceso: acceso abierto
• Materia: Ácido Ascórbico; Cobre; Radicales Libres; Óxido-Reducción; Antioxidantes; Ascorbic Acid; Copper; Free Radicals; Redox; Antioxidants

Ascorbate autoxidation catalyzed Cu2 + is performed via a first order reaction , a process that is dependent upon the concentration of Cu2 + and that follows a saturation emetic . This suggests that in the sequence an intermediate complex catalyst which would limit the formation of reaction products , one of which is a free hydroxyl radical is formed. Thiourea markedly inhibits autoxidation reaction , while it has no effect glycerol . Ascorbate and Cu2 + , used at concentrations that autoxidation occurs, do not cleave the disulfide bond of DTNB . Histidine and citrate inhibit both autoxidation reaction as breaking of the disulfide bond of DTNB . These results suggest that the rupture of the disulfide bridge of DTNB be realized with the intervention of the hydroxyl free radicals generated by the ascorbate system / Cu + , and in parallel by a process of reduction or hydrolysis .