The peptide-catalyzed Maillard reaction - Characterization of C-13 reductones

The reaction pathways of amino acids and reducing sugars are now fully understood. The focus in the last few years, however, has turned to the reaction of peptides and proteins with reducing sugars. We have investigated the reaction of gamma-aminobutanoic acid, the heptapeptide N alpha-Acetyl-Lys-Lys-beta-Ala-Lys-beta-Ala-Lys-Gly, and the model protein beta-casein in Maillard reactions with 1-C-13 arabinose. Characterization of C-13-labeled acetic acid and norfuraneol by gas chromatography-mass spectrometry and nuclear magnetic resonance revealed new formation pathways. The results demonstrate significant differences in the labeling pattern of the products depending on the amine used, indicating different formation pathways of acetic acid and norfuraneol.