The in vivo antioxidant effects of high levels of dietary paprika carotenoids were investigated by comparison to a high level of β-carotene and to a physiological level of vitamin E. Dietary (vitamin E deficiency) and chemical (CCl4) treatments were used to produce lipid peroxidation in vivo in order to demonstrate the antioxidant effects of paprika carotenoids and β-carotene, which were determined by the urinary excretion of aldehydic secondary lipid oxidation products. Rats were fed a diet which contained either a normal level (0.003%) of vitamin E as RRR-α-tocopherol acetate (NE), a vitamin E deficient diet (-E), or a vitamin E deficient diet supplemented with 0.5% or 1.0% paprika carotenoids (-E + PCI or -E + PCII), or 0.5% β-carotene (-E + BC) for 18 weeks. One group of animals on the NE diet was also stressed with CCl4 (NE + CCl4). Urine samples were separated by high performance liquid chromatography (HPLC) into six fractions which contained free and conjugated malondialdehyde (MDA) and four groups of other secondary aldehydic lipid peroxidation products. Results show that the antioxidant treated groups, NE, -E + BC, -E + PCI, and -E + PCII, all had lower levels of urinary excretion of free and conjugated MDA, non-MDA carbonyl compounds, and excretion of all (MDA and non-MDA) aldehydic secondary lipid oxidation products than the oxidatively stressed -E and NE + CCl4 groups. Rats fed the NE diet, however, had significantly higher body weights at 18 weeks than the other groups. The results indicate that dietary paprika carotenoids and β-carotene, when fed at high levels, exhibit similar antioxidant effects on inhibiting in vivo lipid peroxidation but do not compensate for the role of physiological levels of vitamin E in normal growth and weight gain.
Bibliographical noteFunding Information:
This work was supported in part by a grant from Kalsec, Inc., Kalamazoo, MI and in part by the Minnesota Agricultural Experiment Station. The authors express thanks to Dr. Song-Suk Kim for her assistance with the feeding of the experimental animals and collection of urine samples for analysis. Appreciation is also expressed to Kalsec, Inc. for the gift of β-carotene and paprika extract and the HPLC analysis of these compounds.
Copyright 2008 Elsevier B.V., All rights reserved.
- In vivo lipid oxidation
- Paprika carotenoids
- Secondary oxidation products
- Vitamin E