Abstract
In this work the oxidation of five a-aminoacids (glycine, alanine, valine, leucine and norleutine) by permanganate ion in an aqueous phosphate buffer solution were studied. The results showed that the reaction proceed in two pathways. The first is noncatalyzed and the second is autocatalyzed by the colloidal manganese dioxide resulted from the first pathway. The dependences of the noncatalyzed oxidation reaction on the pH of the medium was utilized in calculation of the rate constant for the oxidation of zwitter ionic (kHA) and anionic (kA) forms.