Indole-3-methanol is the main product of the oxidation of indole-3-acetic acid catalyzed by two cytosolic basic isoperoxidases from Lupinus.

The nature of the products of the auxin catabolism mediated by both basic and acidic isoperoxidases has been studied. While indole-3-methanol is only a minor product of the oxidation of indole-3-acetic acid catalyzed by extracellular acidic isoperoxidases, it is the only product of the oxidation of indole-3-acetic acid catalyzed by two cytosolic basic isoperoxidases (EC 1.11.1.7) from lupin (Lupinus albus L.) hypocotyls. The putative indole-3-methanol formed by these latter isoperoxidases was isolated and then characterized by mass spectrometry and (1)H-nuclear magnetic resonance spectrometry. These results are discussed with respect to the diversity and compartmentation of the catabolism of indole-3-acetic acid in plant tissues.