Ulcerative colitis: Timeline to a cure

Figure 1 The redox-mediated reaction between 5-aminosalicylic acid, functioning as a reducing agent, and hydrogen peroxide, an oxidizing agent, involves the transfer of electrons. In this process, a single molecule of reduced 5-aminosalicylic acid (5-ASA) donates two electrons, accompanied by two protons, to reduce one molecule of hydrogen peroxide into two molecules of water. In the process, 5-ASA is oxidized to the corresponding 5-ASA quinone imine. The reaction is spontaneous but enhanced by peroxidase enzymes found in the inflammatory field or colonic bacteria. 5-ASA: 5-aminosalicylic acid; H₂O₂: Hydrogen peroxide; H₂O: Water; QI: Quinone imine.