An electron spin resonance study of the reactions of lipid peroxyl radicals with antioxidants

Journal Article · Thu Sep 06 04:00:00 EDT 1990 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100381a043· OSTI ID:5449224

Zhu, J; Johnson, W J; Sevilla, C L; Herrington, J W; Sevilla, M D ^[1]

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1. Oakland Univ., Rochester, MI (USA)

The reactions of lipid carbon-centered radicals and their corresponding peroxyl radicals (RO{sub 2}{sup {sm bullet}}, LO{sub 2}{sup {sm bullet}}) with five phenolic antioxidants (BHT, BHA, PG, TBHQ, and vitamin E) in frozen saturated and unsaturated lipids at low temperatures have been elucidated through electron spin resonance spectroscopy. The lipid radicals are formed after the {gamma} or UV irradiation of the lipid matrices in the absence or presence of oxygen at 77 K. Upon warming oxygenated samples to 135 K, molecular oxygen adds to the carbon radicals forming peroxyl radicals. At 170 K peroxyl radicals in tributyrin react with added antioxidants (AH) to form antioxidant radicals (A{sup {sm bullet}}). The relative rates of reactions of these five antioxidants with the peroxyl radical of tributyrin decrease in the order BHT > TBHQ > E {>=} PG > BHA. For the reactions with triolein and trilinolein peroxyl radicals, the order of reactivity is BHT > E > BHA > TBHQ. This difference in reaction order of antioxidants in tributyrin and unsaturated lipids is explained by a dispersion model of antioxidants in lipid matrices.

• DOE Contract Number: FG02-86ER60455
• OSTI ID: 5449224
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 94:18; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

553000* -- Agriculture & Food Technology
60 APPLIED LIFE SCIENCES
ANTIOXIDANTS
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
ELECTRON SPIN RESONANCE
FOOD INDUSTRY
GAMMA RADIATION
INDUSTRY
IONIZING RADIATIONS
LIPIDS
LOW TEMPERATURE
MAGNETIC RESONANCE
ORGANIC COMPOUNDS
PEROXY RADICALS
RADIATIONS
RADICALS
RESONANCE
ULTRAVIOLET RADIATION
VITAMIN E
VITAMINS