One-electron reduction potentials reported in Table includes several redox reactions of DPPH• that present higher positive E red values than D12. Despite their E red values imply these reactions are more exergonic and thermodynamically favoured than the ones previously proposed, they were unfea-Table : One-electron reduction potentials, in eV, of DPPH• in the presence of Al 3+ complexes at pH=5.5, and relative reduction potential with respect to the values in the absence of aluminum. In the case of D1, D2, D5a, D5b, D8 and D10 the reactions are classified as electron transfer process and therefore, a value of 0.27 eV have been considered as the theoretical reference of the reduction potential without aluminum. In the case of D3, D4, D6, D7 and D9, since the reactions are of proton-coupled electron-transfer type, we consider +0.32 eV as the reference in absence of aluminum.