Abstract
Chain-breaking reactions against lipid peroxidation performed by carotenes, including β-carotene (β-CAR) and lycopene (LYC), have been studied using density functional theory. We chose linoleic acid (LAH) as the lipid model and examined two mechanisms: hydrogen abstraction and addition. Our computed reaction diagrams reveal that the addition mechanism is able to offer a larger extent of chain-breaking protection than hydrogen abstraction. In the case of hydrogen abstraction, the resulting carotene radical CAR(-H)' has a smaller O2 affinity than the linoleic acid radical (LȦ). Formation of the addition adduct radical ROO-CAṘ is energetically favorable, and it has an even smaller tendency to react with O2 than CAR(-H)̇. Comparatively, ROO-β-CAṘ is less likely to react with O2 than ROO-LYĊ. Both the hydrogen abstraction and addition radicals (CAR(-H)̇ and ROO-CAṘ) react readily with a second ROȮ radical via either hydrogen abstraction or addition.
| Original language | English |
|---|---|
| Pages (from-to) | 15699-15708 |
| Number of pages | 10 |
| Journal | Journal of Physical Chemistry B |
| Volume | 113 |
| Issue number | 47 |
| DOIs | |
| Publication status | Published - 2009 Nov 26 |
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All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry
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Chain-breaking activity of carotenes in lipid peroxidation : A theoretical study. / Guo, Jian Jhih; Hsieh, Hong Yi; Hu, Ching-Han.
In: Journal of Physical Chemistry B, Vol. 113, No. 47, 26.11.2009, p. 15699-15708.Research output: Contribution to journal › Article
TY - JOUR
T1 - Chain-breaking activity of carotenes in lipid peroxidation
T2 - A theoretical study
AU - Guo, Jian Jhih
AU - Hsieh, Hong Yi
AU - Hu, Ching-Han
PY - 2009/11/26
Y1 - 2009/11/26
N2 - Chain-breaking reactions against lipid peroxidation performed by carotenes, including β-carotene (β-CAR) and lycopene (LYC), have been studied using density functional theory. We chose linoleic acid (LAH) as the lipid model and examined two mechanisms: hydrogen abstraction and addition. Our computed reaction diagrams reveal that the addition mechanism is able to offer a larger extent of chain-breaking protection than hydrogen abstraction. In the case of hydrogen abstraction, the resulting carotene radical CAR(-H)' has a smaller O2 affinity than the linoleic acid radical (LȦ). Formation of the addition adduct radical ROO-CAṘ is energetically favorable, and it has an even smaller tendency to react with O2 than CAR(-H)̇. Comparatively, ROO-β-CAṘ is less likely to react with O2 than ROO-LYĊ. Both the hydrogen abstraction and addition radicals (CAR(-H)̇ and ROO-CAṘ) react readily with a second ROȮ radical via either hydrogen abstraction or addition.
AB - Chain-breaking reactions against lipid peroxidation performed by carotenes, including β-carotene (β-CAR) and lycopene (LYC), have been studied using density functional theory. We chose linoleic acid (LAH) as the lipid model and examined two mechanisms: hydrogen abstraction and addition. Our computed reaction diagrams reveal that the addition mechanism is able to offer a larger extent of chain-breaking protection than hydrogen abstraction. In the case of hydrogen abstraction, the resulting carotene radical CAR(-H)' has a smaller O2 affinity than the linoleic acid radical (LȦ). Formation of the addition adduct radical ROO-CAṘ is energetically favorable, and it has an even smaller tendency to react with O2 than CAR(-H)̇. Comparatively, ROO-β-CAṘ is less likely to react with O2 than ROO-LYĊ. Both the hydrogen abstraction and addition radicals (CAR(-H)̇ and ROO-CAṘ) react readily with a second ROȮ radical via either hydrogen abstraction or addition.
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U2 - 10.1021/jp907822h
DO - 10.1021/jp907822h
M3 - Article
C2 - 19886649
AN - SCOPUS:71549120372
VL - 113
SP - 15699
EP - 15708
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
SN - 1520-6106
IS - 47
ER -