Ferric Reducing Antioxidant Power FRAP Assay

Ferric Reducing Antioxidant Power (FRAP) Assay... 

In ferric reducing/antioxidant power (FRAP) assay reaction of Fe (Ill)-tripiridyltriazine reduction to Fe (Il)-tripiridyltriazine is used. The latter compound is bright blue and its absorption band is 593 nm [49,50],... 

The Ferric Reducing Antioxidant Power (FRAP) assay uses an electron transfer reaction to assess the reducing ability of a given antioxidant. This colorimetric assay is based on the reduction of an Fe(ni)-tripyridyltriazine (TPTZ) complex to its intensely blue coloured Fe(II) analogue (Schane 4.4) under acidic conditions [11]. 

Muller L, Frohlich K, Bohm V. Comparative antioxidant activities of carotenoids measured by ferric reducing antioxidant power (FRAP), ABTS bleaching assay (aTEAC), DPPH assay and peroxyl radical scavenging assay. Food Chemistry. 2011 129 139-148... 

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. 

Other measurements of antioxidant activity include FRAP (ferric reducing-antioxidant power) (123-126), TRAP (total radical-trapping antioxidant parameter) (123, 127), phycoerythrin assay (128, 129), and test of metal chelating capacity (130, 131), among others. Reviews on methods for testing antioxidant activity have been published (9, 12). 

Hoffm. and Usnea longissima Ach. Lichen species. Turk J Oiem 35 647-661 Behera BC, Verma N, Sonone A et al (2005) Antimicrobial activity of Various solvent extracts of Lichen Usnea ghattensis. Agarkar Research Institute, Pune, India. Biotechnol Lett 27 991-995 Benzie IFF, Strain JJ (1996) The ferric reducing ability of plasma (FRAP) as a measure of antioxidant power the FRAP assay. Anal Biochem 239 70-76 Benzie IFF, Szeto YT (1999) Total antioxidant capacity of teas by the ferric reducing/antioxidant power assay. J Agric Food Chem 47 633-636 Betteridge DJ (2000) What is oxidative stress Metabolism 49 3-8... 

Benzie IFF and Strain JJ. 1996. The ferric reducing ability of plasma (FRAP) as a measure of antioxidant power the FRAP assay. Anal Biochem 239(1 ) 70—76. 

FIA methods based on ferric reducing power similar to the FRAP principle reaction have been used for the determination of ascorbic acid, vitamin E, and total iron. Table 30.1 summarizes most of these studies. Spectrophotometric detection is also used in many of these studies because of the chromogenic effect from Fe oxidation, which changes with complex ligands, such as TPTZ, o-phenanthroline, cyanide, and DPPH. Different FIA manifolds have also been investigated and proposed, from single to multiple lines. Therefore, like other chromogenic antioxidant tests, the FRAP assay has the potential for several flow injection adaptations. 

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