Vitamin antioxidant capacity

Gliszczyhska-Swigl, A. (2006). Antioxidant activity of water soluble vitamins in the TEAC (trolox equivalent antioxidant capacity) and the FRAP (ferric reducing antioxidant power) assays. Food Chemistry, Vol.96, No.l, (May 2006), pp. 131-136, ISSN 0308-8146. 

CARBONNEAU M-A, LEGER c L, MONNIER L (1997) Supplementation with wine phenolic compormds increases the antioxidant capacity of plasma and vitamin E of low-density lipoprotein without changing the lipoprotein Cu -oxidizability possible explanation by phenolic location, European Journal of Clinical Nutrition, 51, 682-90. 

Another point is the concentration of the antioxidant which, in order to have physiological relevance, should be in the physiological range, i.e., not above 1 to 5 aM. Finally, when evaluating antioxidant capacities of foods and food extracts, one should take into account the presence of all the possible antioxidant molecules (phenols, vitamin E, etc.) to explain the results because interactions can occur between antioxidant molecules. 

The major lipid-soluble antioxidant primarily associated with lipid membranes is a-tocopherol (vitamin E). Circulating a-tocopherol is carried by chylomicrons, LDL and HDL and also has extracellular antioxidant capacities. As a chain-breaking antioxidant, it short circuits the propagation phase of lipid peroxidation because the peroxyl radical will react with a-tocopherol more rapidly than a polyunsaturated ffitty acid (Burton and Traber, 1990). The resulting a-tocopheryl radical reacts with a second peroxyl radical to form an inactive, nonradical complex. In vitro, ascorbate regenerates the tocopheryl radical into its native non-radical form (Burton and Traber, 1990). 

Situnayake et al., 1991). No correlation between disease activity and serum vitamin E concentrations was found, but it was su ested that such patients might suffer a reduced antioxidant capacity. However, it is conceivable that a decreased serum antioxidant status is a primary event in the evolution of RA. Recent studies (Heliovaara etal., 1994) have demonstrated that lowered levels of vitamin E, /3-carotene and selenium (required for glutathione peroxidase) together may be a risk fector for subsequent development of RA. 

Repeated periods of exercise reduce the likelihood of damage to skeletal muscle during subsequent bouts of the same form of exercise and this appears to be associated with an increase in the activity of muscle SOD (Higuchi et al. 1985), a reduced level of lipid peroxidation products during exercise in trained rats (Alessio and Goldfarb, 1988), and a modification of the concentration of antioxidants and activity of antioxidant enzymes in trained humans (Robertson etal., 1991). Packer and colleagues (Quintanilha etui., 1983 Packer, 1984) have also examined the exercise endurance of animals of modified antioxidant capacity and found that vitamin E-deficient rats have a reduced endurance capacity, while Amelink (1990) has reported that vitamin E-deficient rats have an increased amount of injury following treadmill exercise. 

Galvis-Sanchez AC, Gil-Izquierdo A and Gil MI. 2003. Comparative study of six pear cultivars in terms of their phenolic and vitamin C contents and antioxidant capacity. J Sci Food Agric 83 995-1003. 

Kalt W, Forney CF, Martin A and Prior RL. 1999. Antioxidant capacity, vitamin C, and anthocyanins after fresh storage of small fruits. J Agric Food Chem 47 4638-4644. 

The antioxidant capacity of a food is derived from the accumulative and synergistic antioxidant power of vitamins, polyphenols, carotenoids, and other minor constituents (Liu and others 2008). 

Apak R, Guylu K, Mustafa 6 and Karademir SE. 2004. Novel total antioxidant capacity index for dietary polyphenols and vitamins C and E, using their cupric ion reducing capability in the presence of neocuproine CUPRAC Method. J Agric Food Chem 52(26) 7970-7981. 

Elez-Martinez P and Martin-Belloso O. 2007. Effects of high intensity pulsed electric field processing conditions on vitamin C and antioxidant capacity of orange juice and gazpacho, a cold vegetable soup. Food Chem 102(l) 201-209. 

Gil MI, Tomas-Barberan FA, Hess-Pierce B and Kader AA. 2002. Antioxidant capacities, phenolic compounds, carotenoids, and vitamin C contents of nectarine, peach, and plum cultivars from California. J Agric Food Chem 50(17) 4976-4982. 

As has been explained in previous chapters, the antioxidant capacity of fruits and vegetables is a function of the amounts and types of phytochemicals that are present in the fresh tissues. However, the individual contribution to the total antioxidant capacity varies widely. Various studies have demonstrated that phenols and flavonoids contribute to a higher extent than ascorbic acid, carotenoids, and others to the antioxidant capacity of fmits and vegetables (Robles-Sanchez and others 2007). It has been observed that a given content of vitamin E in fruits contributes significantly more to the antioxidant capacity than the same content of ascorbic acid. 

Odriozola-Serrano I, Soliva-Fortuny R, Gimeno-Ano V and Martin-Belloso O. 2008a. Kinetic study of anthocyanins, vitamin C, and antioxidant capacity in strawberry juices treated by high-intensity pulsed electric fields. J Agric Food Chem 56 8387-8393. 

Apak R, Giiglii K, Ozytirek M, Karademir SE. Novel Total Antioxidant Capacity Index for Dietary Polyphenols and Vitamins C and E, Using Their Cupric Ion Reducing Capability in the Presence of Neocuproine CUPRAC Method. Journal of Agricultural and Food Chemistry. 2004 52 (26) 7970-7981. 

The lipoxygenase system also competes for released arachidonic acid in a way that seems to be tissue-selective, giving rise to hydroperoxy fatty acids (HPETE) which can be converted into leukotrienes or reduced to hydroxy fatty acid (HETE) products [115]. The basic scheme for these metabolic conversions involving arachidonic acid is presented in Figure 5.2. Both of the main enzymatic pathways of arachidonic acid metabolism are thought to involve free-radical-mediated reactions [108] and the antioxidant capacity of vitamin E could therefore allow the vitamin to modify the products of these pathways. 

C13. Cao, G., Russell, R. M., Lischner, N., and Prior, R. L., Serum antioxidant capacity is increased by consumption of strawberries, spinach, red wine or vitamin C in elderly women. J. Nutr. 128,... 

Long-term administration (between 12 and 36 months) of vitamin C and E alone or in combination at respective daily dosages of 500 and 182 mg (as RRRA acetate) were not capable of modifying the antioxidant capacity of plasma (94),... 

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