Lipids

, Volume 31, Issue 4, pp 357–365

Effect of α-tocopherol and Trolox on the decomposition of methyl linoleate hydroperoxides

  • Anu Hopia
  • Shu-Wen Huang
  • Edwin N. Frankel
Article

DOI: 10.1007/BF02522920

Cite this article as:
Hopia, A., Huang, SW. & Frankel, E.N. Lipids (1996) 31: 357. doi:10.1007/BF02522920

Abstract

To clarify the mechanisms of antioxidant action, the effect of α-tocopherol and its water-soluble carboxylic acid derivative, Trolox, was studied on the decomposition of methyl linoleate hydroperoxides (MeLoOOH). Decomposition rate and the distribution of autoxidation products formed from MeLoOOH were followed by analyzing the volatile and nonvolatile products by static headspace gas chromatography and normal-phase high-performance liquid chromatography, respectively. Both α-tocopherol and Trolox markedly inhibited the decomposition of MeLoOOH in a concentration-dependent way. In the absence of antioxidants, MeLoOOH was completely decomposed after incubation for 48 h at 60°C, and in the presence of equal molar concentration of antioxidants only 6–7% of initial MeLoOOH was decomposed even after 280 h of incubation. MeLoOOH produced 1.2% methyl linoleate hydroxy compounds (MeLoOH) in the presence of α-tocopherol and 3.8% in the presence of Trolox. Both antioxidants inhibited the formation of volatile decomposition products and the formation of ketodiene compounds. The hydroxy compounds may be formed by the reaction of alkoxy radical and hydrogen donating antioxidants. Conversion of MeLoOOH into stable MeLoOH demonstrated that the antioxidants α-tocopherol and Trolox trap alkoxyl radicals by H-donation.

Abbreviations

GC

gas chromatography

HPLC

high-performance liquid chromatography

MeLo

methyl linoleate

MeLoOH

methyl linoleate hydroxy compounds

MeLoOOH

methyl linoleate hydroperoxides

Copyright information

© AOCS Press 1996

Authors and Affiliations

  • Anu Hopia
    • 1
  • Shu-Wen Huang
    • 1
  • Edwin N. Frankel
    • 1
  1. 1.Department of Food Science and TechnologyUniversity of CaliforniaDavis
  2. 2.Department of Applied Chemistry and MicrobiologyUniversity of HelsinkiFinland