Antioxidants alpha tocopherol

Takahashi, A., Shibasaki-Kitakawa, N., and Yonemoto, T., A rigorous kinetic model for beta-carotene oxidation in the presence of an antioxidant, alpha-tocopherol, J. Am. Oil Chem. Soc., 80, 1241, 2003. 

The course of the oxidation of any animal fat follows a typical pattern. A period of very limited oxygen uptake (the induction period) is followed by a phase of rapid oxidation (see Fig. 4). The induction period is due to the presence in animal fats of varying amounts of a natural antioxidant, alpha tocopherol. The activity of this and other antioxidants is discussed in Section V. 

Free radical scavenging activities of different phenolic acids, caffeic acid (CA), ferulic acid (FA) and p-coumaric acid (p CA) and natural antioxidants alpha tocopherol (alpha-toco) and BHA a synthetic antioxidant were compared with sinapic acid (SA). As indicated in Figure 15.10 under the tested conditions, the radical scavenging activity of the phenolic acids in the DPPH system decreased in the following order ... 

The term vitamin E describes a family of eight antioxidants, four tocopherols, alpha (a), beta ((3), gamma (y) and delta (8), and four tocotrienols (also a, (3, y, and 8). a-Tocopherol is present in nature in only one form, RRR a-tocopherol. The chemical synthesis of a-tocopherol results in eight different forms (SRR, SSR, SRS, SSS, RSR, RRS, RSS, RRR), only one of which is RRR a-tocopherol. These forms differ in that they can be right (R) or left (S) at three different places in the a-tocopherol molecule. RRR a-tocopherol is the only form of vitamin E that is actively maintained in the human body and is therefore the form of vitamin E found in the largest quantities in the blood and tissue. A protein synthesized in the liver (a-TTP alpha-tocopherol transfer protein) preferentially selects the natural form of vitamin E (RRR a-tocopherol) for distribution to the tissues. However, the mechanisms for the regulation of vitamin E in tissues are not known... 

Antioxidants (magnesium,ascorbic acid, alpha-tocopherol)... 

Street, D.A. et al.. Serum antioxidants and myocardial infarction are low levels of carotenoids and alpha-tocopherol risk factors for myocardial infarction Circulation, 90, 1154, 1994. 

Reboul, E, Thap, S, Perrot, E, Amiot, MJ, Lairon, D, and Borel, P, 2007a. Effect of the main dietary antioxidants (carotenoids, gamma-tocopherol, polyphenols, and vitamin C) on alpha-tocopherol absorption. Eur J Clin Nutr 61, 1167-1173. 

Mein, J. R., N. Chongvirihaphan, and X. D. Wang. 2006. The effect of combined antioxidant supplementation (beta-carotene, ascorbic acid and alpha-tocopherol) on the expression of CMOl and CM02 in smoke-exposed ferrets. In American Association of Cancer Research Frontiers in Cancer Prevention Research Meeting. Boston, MA. 

Kim, Y., Chongviriyaphan, N., Liu, C., Russell, R.M., and Wang, X.D. 2006. Combined antioxidant (beta-carotene, alpha-tocopherol and ascorbic acid) supplementation increases the levels of lung retinoic acid and inhibits the activation of mitogen-activated protein kinase in the ferret lung cancer model. 

Palozza P and Krinsky NI. 1992b. Beta-carotene and alpha-tocopherol are synergistic antioxidants. Arch Biochem Biophys 297 184—187. 

Buettner, G. R., 1993, The pecking order of free radicals and antioxidants hpid peroxidation, alpha-tocopherol, and ascorbate, Arch. Biochem. Biophys. 300 535-543. 

Vitamin E may be indicated in some rare forms of anemia such as macrocytic, megaloblastic anemia observed in children with severe malnutrition and the hemolytic anemia seen in premature infants on a diet rich in polyunsaturated fatty acids. Also anemia s in malabsorption syndromes have shown to be responsive to vitamin E treatment. Finally, hemolysis in patients with the acanthocytosis syndrome, a rare genetic disorder where there is a lack of plasma jS-lipoprotein and consequently no circulating alpha tocopherol, responds to vitamin E treatment. In neonates requiring oxygen therapy vitamin E has been used for its antioxidant properties to prevent the development retrolental fibroplasia. It should be noted that high dose vitamin E supplements are associated with an increased risk in allcause mortality. 

Effect of alpha-tocopherol on the cardiac antioxidant defense system and atherogenic lipids in cigarette smoke-inhaling mice. Inhal Toxicol 2003 15(5) 513-522. 

O Byrne, D.J., Devaraj, S., Grundy, S.M., and Jialal, I., Comparison of the antioxidant effects of Concord grape juice flavonoids alpha-tocopherol on markers of oxidative stress in healthy adults. Am. J. Clin. Nutr., 76, 1367, 2002. 

Andre, C. M., Oufir, M., Guignard, C., Hoffmann, L., Hausman, J. F., Evers, D., Larondelle, Y. (2007b). Antioxidant profiling of native Andean potato tubers (Solanum tuberosum L.) reveals cultivars with high levels of beta-carotene, alpha-tocopherol, chlorogenic acid, and petanin. J. Agric. Food Client., 55, 10839-10849. 

Mallet, J. R, C. Cerrati, E. Ucciani, J. Gamisans, and M. Gruber. 1994. Antioxidant activity of plant leaves in relation to their alpha-tocopherol content. Food Chem. 49 61-65. 

Alpha tocopherol Beta, delta, and gamma are considered to be more effective antioxidants Incompatible with peroxides and metal ions, especially iron, and copper. May be absorbed into plastic. Protect from light, and oxygen during storage... 

Andrikopoulos et al. (124) separated triglycerides, together with nine synthetic phenolic antioxidants most commonly used to prevent oxidation of edible oils and fats, as well as the natural antioxidants tocopherol and alpha-tocopherol acetate by HPLC using a reversed-phase Cl8 column and gradient elution with water/acetonitrile/methanol/isopropanol. Except for dilution of the oil with isopropanol/hexane, no further sample preparation was required. Ultraviolet detection was applied. The synthetic antioxidants PG, OG, DG, BHA, TBHQ, BHT, Ionox 100, THBP, and NDGA, as well as alpha- and delta-tocopherol and alpha-tocopherol acetate were separated. 

Niki E. 1996. alpha-Tocopherol. In Cadenas E, Packer L, Eds. Handbook of Antioxidants. New York Marcel Dekker, pp. 3-25. 

VWseman et al., 1990). Tocopherol appears to have a dual role in stabilizing liposomes it serves primarily not only as an antioxidant but also stabilizes the bilayer by speciLc binding to phospholipid molecules (Hernandez-Caselles et al., 1990). This interaction appears to be between the hydroxy groups of alpha-tocopherol and the fatty acyl carbonyl of phospholipids (Urano et al., 1990). 

Yanagawa, K., Takeda, H., Egashira, T., Matsumiya, T., Shibuya, T., and Takasaki, M. (2001). Changes in antioxidative mechanisms in elderly patients with non-insulin-dependent diabetes mellitus. Investigation of the redox dynamics of alpha-tocopherol in erythrocyte membranes. Gerontology 47 150-157. 

Although the crude material has 35% acetone solubles, we found only traces of compounds that react with the Emmerie-Engel reagent, a test for potential antioxidants, particularly tocophe-rols. In particular, no spot was found for alpha-tocopherol. 

L15. Linseisen, J., Hoffmann, J., Lienhard, S., Jauch, K. W., and Wolfram, G., Antioxidant status of surgical patients receiving TPN with an omega-3-fatty acid-containing lipid emulsion supplemented with alpha-tocopherol. Clin. Nutr. 19, 177-184 (2000). 

N4. Newaz, M. A., and Nawal, N. N., Effect of alpha-tocopherol on lipid peroxidation and total antioxidant status in spontaneously hypertensive rats. Am. J. Hypertens. 11, 1480—1485... 

Dipyridamole has also been shown to have antioxidant effects (19). Antioxidants act to remove harmful reactive-oxygen species and protect low-density lipoproteins (LDL) from oxidation oxidized LDL plays a key role in the development and propagation of atherosclerosis. The antioxidant effects of dipyridamole may be both direct (by scavenging oxygen and hydroxyl radicals, inhibiting lipid peroxidation and oxidative modification of LDL) (20-22) and indirect (via adenosine, which reduces superoxide anion generation). Dipyridamole has been shown to be a more effective anioxidant than ascorbic acid, alpha-tocopherol, or probucol (22). 

Figure 1. The autoxidation of linoleic acid in SDS micelles. The initiator is first injected into the bulk buffer phase and then the antioxidant is injected. The oxygen-electrode trace shown is for alpha-tocopherol as the antioxidant (Si) o...

Morreale, M. and Livrea, M.A., Synergistic effect of glycolic acid on the antioxidant activity of alpha-tocopherol and melatonin in lipid bilayers and in human skin homogenates, Biochem. Mol. Biol. Int., 42, 1093-1102, 1997. 

Mireles-Rocha, H. et al., UVB photoprotection with antioxidants effects of oral therapy with d-alpha-tocopherol and ascorbic acid on the minimal erythema dose, Acta Derm. Venereol., 82, 21, 2002. 

Satoh, K., Kadofuku, T., and Sakagami, H., Effect of Trolox, a synthetic analog of alpha-tocopherol, on cytotoxicity induced by UV irradiation and antioxidants, Anticancer Res., 17, 2459, 1997. 

Hamzawi, L.F. 1990. Role of phospholipids and alpha-tocopherol as natural antioxidants in buffalo butterfat. Milchwissenschaft. 45, 95-97. 

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