Oxidative catabolism of alpha-tocopherol in rat liver microsomes
Related Experiment Video
Updated: Oct 7, 2026

Determination of Fatty Acid Oxidation and Lipogenesis in Mouse Primary Hepatocytes
Published on: August 27, 2015
H Van Houte1, E De Hoffmann, P P Van Veldhoven
1Department of Clinical Chemistry, Katholieke Universiteit Leuven, Belgium.
Abstract:
The goal of this study was to clarify the mechanism responsible for the catabolism of alpha-tocopherol. The vitamin, bound to albumin, was incubated with rat liver microsomes and appeared to be broken down. Optimal production of the metabolite was obtained when 1 mg of microsomal protein was incubated with 36 microM of alpha-tocopherol in the presence of 1.5 mM of NADPH. Chromatographic and mass spectrometric analyses of the metabolite led to the conclusion that it consists of an omega-acid with an opened chroman ring, although we could not perform nuclear magnetic resonance analysis to confirm this. Our data show that alpha-tocopherol is omega-oxidized to a carboxylic acid and that this process can occur in rat liver microsomes in the presence of NADPH and O2. The oxidation to the quinone structure appears to be a subsequent event that may be artifactual and/or catalyzed by a microsomal enzyme(s).
Related Concept Videos
Radical Autoxidation
Phase I Reactions: Oxidation of Aliphatic and Aromatic Carbon-Containing Systems
Oxidation reactions are fundamental in aromatic carbon-containing systems. An example is the hydroxylation of phenobarbital, a process that transforms it into...
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
Bioactivation and Tissue Toxicity
Phase I Oxidative Reactions: Overview
Lipid Catabolism

