Oxidant Scavenging Capacity

The antioxidative role of anthocyanins and flavones in providing stable blue flower colors in the angiosperms has been studied. The leaf anthocyanins and flavones showed a protective effect against UV-B radiation. These protective UV-B flavonoids in angiosperms were mainly kaempferol (9), quercetin (10), cyanidin (51), luteolin (65), and isoorientin C-glycoside (flavone C-glycoside, 66) (Fig. 14) [35]. 

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Lichtenthaler, R. et al.. Total oxidant scavenging capacities of Euterpe oleracea Mart. (a9ai) fruits, Int. J. Food Sci. Nutr, 56, 53, 2005. 

Lichtenthaler R and Marx F. 2005. Total oxidant scavenging capacities of common European fruit and vegetable juices. J Agric Food Chem 53(1) 103—110. 

R6. Regoli, F., Nigro, M., Bompadre, S., and Winston, G. W., Total oxidant scavenging capacity (TOSC) of microsomal and cytosolic fractions from Antarctic, Arctic and Mediterranean scallops Differentiation between three potent oxidants. Aquat. Toxicol. 49, 13-25 (2000). 

Peroxynitrite (ONOO-) is a cytotoxic reactive species that is formed by the reaction of nitric oxide and superoxide. Methods for measuring the scavenging capacity of peroxynitrite usually depend on either the inhibition of tyrosine nitration or the inhibition of dihydrorhodamine 123 (DHR) oxidation to rhodamine 123 (MacDonalds-Wicks and... 

Sanchez-Moreno C, Larrauri JA and Saura-Calixto F. 1999b. Free radical scavenging capacity and inhibition of lipid oxidation of wines, grape juices and related polyphenolic constituents. Food Res Int 32(6) 407—412. 

Figure 6 Effect of scavenging capacity for e q on the number of electrons scavenged in aqueous solutions of nitrous oxide, nitrate, and selenate. Experimental data nitrate—( ) [77], ( ) [78] ...

Chlorogenic acids are shown to have some desirable biological activities. Most of their property relates to their function as antioxidants, evidenced by their activity to scavenge free radicals, to inhibit the formation of free radicals, and to block the oxidation reaction. However, other activities based on mechanisms other than scavenging capacity cannot be ignored. Also, further tests for the in vivo bioactivity of chlorogenic acids are to be needed. However, it is expected that chlorogenic acids may be beneficial to human health. 

The total oxygen-scavenging capacity (TOSC) assay is based on the oxidation of a-keto-y -methiolbutyric acid (KMBA) to ethylene. Ethylene formation is monitored by gas chromatography in the course of reaction and areas below the kinetic curves for control sample and analyzed sample are compared. The oxidant is usually ABAP, but other oxidants were also used and compared (R5, W12). 

On the other hand, there is growing evidence for the role of the nitric oxide radical ( NO) in vascular endothelial damage. It is speculated that ( NO) scavenging activity may contribute to the therapeutic effects of the flavonoids. On the basis of this hypothesis,recently the ( NO) scavenging capacity of certain flavonoids, as hydroxyethylrutosides, has been investigated by Van Acker et al. [188],... 

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