title: Oxidative versus Non-oxidative Decarboxylation of Amino Acids: Conditions for the Preferential Formation of Either Strecker Aldehydes or Amines in Amino Acid/Lipid-Derived Reactive Carbonyl Model Systems.
abstract: Comparative formation of both 2-phenylethylamine and phenylacetaldehyde as a consequence of phenylalanine degradation by carbonyl compounds was studied in an attempt to understand if the amine/aldehyde ratio can be changed as a function of reaction conditions. The assayed carbonyl compounds were selected because of the presence in the chain of both electron-donating and electron-withdrawing groups and included alkenals, alkadienals, epoxyalkenals, oxoalkenals, and hydroxyalkenals as well as lipid hydroperoxides. The obtained results showed that the 2-phenylethylamine/phenylacetaldehyde ratio depended upon both the carbonyls and the reaction conditions. Thus, it can be increased using electron-donating groups in the chain of the carbonyl compound, small amounts of carbonyl compound, low oxygen content, increasing the pH, or increasing the temperature at pH 6. Opposed conditions (use of electron-withdrawing groups in the chain of the carbonyl compound, large amounts of carbonyl compound, high oxygen contents, low pH values, and increasing temperatures at low pH values) would decrease the 2-phenylethylamine/phenylacetaldehyde ratio, and the formation of aldehydes over amines in amino acid degradations would be favored.
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC) , Carretera de Utrera, km 1, Campus Universitario, Edificio 46, 41013 Seville, Spain.
authors.forename: Rosario
authors.initials: R
authors.lastname: Zamora
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC) , Carretera de Utrera, km 1, Campus Universitario, Edificio 46, 41013 Seville, Spain.
authors.forename: M Mercedes
authors.initials: MM
authors.lastname: León
authors.affiliation: Instituto de la Grasa, Consejo Superior de Investigaciones Científicas (CSIC) , Carretera de Utrera, km 1, Campus Universitario, Edificio 46, 41013 Seville, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Hidalgo
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry*; D003653:Decarboxylation; D008055:Lipids / Q000737:chemistry*; D015416:Maillard Reaction; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D000447:Aldehydes; D000588:Amines; D000596:Amino Acids; D008055:Lipids
keywords: Maillard reaction; Strecker aldehydes; Strecker-type degradation; amino acid degradation; biogenic amines; lipid oxidation; reactive carbonyls