Antioxidants vitamin C

Overproduction of free radicals by erythrocytes and leukocytes and iron overload result in a sharp increase in free radical damage in T1 patients. Thus, Livrea et al. [385] found a twofold increase in the levels of conjugated dienes, MDA, and protein carbonyls with respect to control in serum from 42 (3-thalassemic patients. Simultaneously, there was a decrease in the content of antioxidant vitamins C (44%) and E (42%). It was suggested that the iron-induced liver damage in thalassemia may play a major role in the depletion of antioxidant vitamins. Plasma thiobarbituric acid-reactive substances (TBARS) and conjugated dienes were elevated in (3-thalassemic children compared to controls together with compensatory increase in SOD activity [386]. The development of lipid peroxidation in thalassemic erythrocytes probably depends on a decrease in reduced glutathione level and decreased catalase activity [387]. 

Bell pepper is rich in antioxidant vitamin C. It helps to fight off colds, asthma, bronchitis, respiratory infections, cataracts, macular degeneration, angina, atherosclerosis, and cancer. 

Darr, D. et al., Effectiveness of antioxidants (vitamin C and E) with and without sunscreens as topical photoprotectans, Acta Derm. Venerol., 76, 264, 1996. 

Moison, R.M. and Beijersbergen van Henegouwen, G.M., Topical antioxidant vitamins C and E prevent UVB-radiation-induced peroxidation of eicosapentaenoic acid in pig skin. Radiat. Res., 157, 402, 2002. 

HYDROPHOBIZED SILICA NANOCOMPOSITES WITH IMMOBILIZED ANTIOXIDANTS (VITAMINS C AND E)... 

Abstract. Adsorption of antioxidants (vitamins C and E) from aqueous and ethanol solutions on unmodified and partially hydrophobized nanosilica A-200 was studied using UV spectroscopy and quantum chemical methods with consideration for the solvent effects. Antioxidant power of silica nanocomposites with immobilized vitamins was evaluated by measuring the total polyphenolic index following the Folin-Ciocalteu method. It has been shown that immobilization of vitamins on silica surface leads to their stabilization. Being released from the carrier molecules of vitamins do not lose their antioxidant properties... 

Keywords antioxidants, vitamins C and E, partially hydrophobized fumed silica 1. Introduction... 

The lung also possesses nonenzymatic antioxidants such as vitamin E, beta-carotene, vitamin C, and uric acid. Vitamin E is lipid-soluble and partitions into lipid membranes, where it is positioned optimally for maximal antioxidant effectiveness. Vitamin E converts superoxide anion, hydroxyl radical, and lipid peroxyl radicals to less reactive oxygen metabolites. Beta-carotene also accumulates in cell membranes and is a metabolic precursor to vitamin A. Furthermore, it can scavenge superoxide anion and react directly with peroxyl-free radicals, thereby serving as an additional lipid-soluble antioxidant. Vitamin C is widely available in both extracellular and intracellular spaces where it can participate in redox reactions. Vitamin C can directly scavenge superoxide and hydroxyl radical. Uric acid formed by the catabolism of purines also has antioxidant properties and primarily scavenges hydroxyl radical and peroxyl radicals from lipid peroxidation. 

The pro-oxidant chemistry of the natural antioxidants vitamin C, vitamin E, carotenoids and flavonoids. Env. Toxicol. Pharmacol. 11 321-333. 

Certain vitamins that serve as coenzymes (vitamin C) or as precursors of coenzymes (all B group vitamins and certain carotenoids) are commercially produced in bulk amounts, which are used for human nutrition and animal husbandry, as antioxidants (vitamins C and E) and food colorants (vitamin B2, carotenoids). Only a fraction of technically manufactured vitamins is used for inclusion in drugs. 

Vitamin C. The universal antioxidant, vitamin C has diverse roles in health, especially for maintaining skin and for connective tissue repair, along with eye, bone, teeth, and gum health. Except for processed or dried fruits in which the vitamin C content is reduced, all of the twenty superfruits are good to excellent sources of vitamin C, especially in their fresh form. Dried, frozen, and processed superfruits will have lower vitamin C content. 

Nutrient Content high in prebiotic fiber, antioxidant vitamin C, dietary minerals... 

Nutrient Content high in antioxidant vitamin C, dietary minerals Phytochemical Content high in polyphenols, including resveratrol and the richest content of anthocyanins yet described for fruits Color Code red-purple-black... 

There is increasing evidence that in addition to the traditional antioxidative vitamins, other compounds may also have important antioxidative functions in the human body. The antioxidant vitamins C and E, together with other antioxidants from products such as tea, wine and other foods of vegetable origin may thus play a critical role in the reduction or in the delay of the onset of degenerative diseases, including coronary heart diseases (CHD) (Biesalski, 1999). It is not yet well established as to what extent antioxidants have protective properties beyond the levels obtained through a balanced diet (Halliwell, 1997 Stahelin, 1999). 

Heo JH, Hyon-Lee LKM (2013) The possible role of antioxidant vitamin C in Alzheimer s disease treatment and prevention. Am J Alzheimers Dis Other Demen 28 120-125... 

FIGURE 14.1 Antioxidative properties of selected alcoholic beverages (based on Bartosz et al., Biochem. Mol. Biol. Int., 46, 519, 1998). The high antioxidative activity of beers may, to a considerable extent, result from the addition of antioxidants, vitamin C in particular. 

Patients with pulmonary disease usually do not have significant alterations in vitamin and trace element requirements, and they can receive standard doses of these micronutrients. There are some data that support the additional supplementation of antioxidants vitamin C, vitamin E, and / -carotene in pulmonary patients due to a correlation with moderately improved pulmonary function. COPD patients may have an increased burden of oxidants from cigarette smoke or release of oxygen free radicals from inflammatory leukocytes in the lungs, and deficiencies of antioxidants may contribute to ox-idant/antioxidant imbalances in these individuals. The value of supplementation of these substances in COPD will require further clarification. 

Five portions of fruits and vegetables pet day have enough of the antioxidants vitamin C and vitamin E to mitigate some of the problems of aging. 

Because it is at once so familiar and so inscrutable, we will use the example of vitamin C in this chapter as a springboard to explore the wider function and behaviour of antioxidants. Although often defined simply as a water-soluble antioxidant, vitamin C illustrates many of the difficulties we face in trying to define an antioxidant. Here is Tom Kirkwood, eminent researcher on ageing at the University of Newcastle, and presenter of the 2001 BBC Reith lectures, giving a vivid depiction of the action of vitamin C ... 

The initial selection of adjuvants to crinitol was based largely on the above mentioned structure-activity relationship study. Thus, the hydroxy group at C-9 in crinitol seems to be essential to its antibacterial activity. The allylic C-9 hydroxy group is easily oxidized, a possibility which might detoxify crinitol in bacterial systems. Because crinitol possesses two allylic alcohol groups in its molecule (at C-1 and C-9), we combined it with several antioxidants which have been used as food and cosmetic additives. Thus two natural antioxidants, vitamins C and E, and two synthetic antioxidants, BHA and BHT, were chosen for the experiment. While the synthetic antioxidants exhibited antimicrobial activity against all the test bacteria (30), natural antioxidants did not show any activity up to 800... 

All the water-soluble vitamins except vitamin C function as coenzymes. In spite of its name, vitamin C is not actually a vitamin because it is required in fairly high amounts and most mammals are able to synthesize it (Section 22.19). Humans and guinea pigs cannot synthesize it, however, so it must be included in their diets. We have seen that vitamin C and vitamin E are radical inhibitors and therefore are antioxidants. Vitamin C traps radicals formed in aqueous environments, whereas vitamin E traps radicals formed in nonpolar environments (Section 9.8). 

Curcumin has been solubilised in aqueous anionic, cationic and neutral micellar systems and in aqueous buffer. Hie formation of its radical has been observed in all situations. The radical is effectively inert to oxygen and reacts with the natural antioxidants vitamin C and vitamin E and Trolox to a degree dependent on location. It is concluded that the amicarcinogenic activity of c lirctititln may well be a consetiucnce of its ability to access both hydrophobic and hydrophilic environments, act as a radical scavenger and be repaired by both vitamin C and vitamin E. 

Substances that detoxify free radicals include the antioxidants vitamin C, vitamin E, and carotene, which scavenge free radicals, including reactive metabolites and reactive oxygen species generated as a consequence of chemical stress. 

Gordi T, Tan LH, Hong C, Hopkins NJ, Francom SF, Slatter JG, Antal EJ. The pharmacokinetics of linezolid are not affected by concomitant intake of the antioxidant vitamins C and E. J Clin Pharmacol(2003) 43, 1161-7. 

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