Total peroxyl-radical-trapping antioxidant

Wayner, D., Burton, G., Ingold, K.U. and Locke, S. (1985). Quantitative measurement of total peroxyl radical trapping antioxidant capability of human blood plasma by controlled peroxidation. FEBS Lett. 187, 33-37. 

DCFH-DA assay was first developed by Valkonen and Kuusi (1997) as an alternative to measure the total peroxyl radical-trapping antioxidant potential of plasma. This assay uses AAPH to generate peroxyl radicals and DCFH-DA as the oxidizable substrate for the generated radicals. The oxidation of DCFH-DA by peroxyl radicals converts DCFH-DA to dichlorofluorescein. DCF is highly fluorescent (excitation 480 nm, emission 526 nm) and also shows absorbance at 504 nm. Therefore, the produced DCF can be monitored either fluorometrically or spectrophotometrically. 

Valkonen M and Kuusi T. 1997. Spectrophotometric assay for total peroxyl radical-trapping antioxidant potential in human serum. J Lipid Res 38(4) 823-833. 

Wayner DD, Burton GW, Ingold KU Barclay LR Locke SJ. 1987. The relative contributions to the total peroxyl radical-trapping antioxidant activity of human blood plasma. Biochim Biophys Acta 924 408-419. 

TRAP, Total peroxyl-radical-trapping antioxidant capability of plasma TEAC, Trolox equivalent antioxidant capacity FRAP, ferric-reducing activity of plasma ORAC, oxygen-radical-absorbing capacity PCA, perchloric acid-soluble fraction ABAP, 2,2 -azobis(2-amidoproane). 

TRAP, Total peroxyl-radical-trapping antioxidant capability of plasma. 

TRAP Total peroxyl radical scavenging antioxidant capacity 3 (113)... 

Cabrini, L., Barzanti, V., Cipollone, M., Fiorentini, D., Grossi, G., Tolomelli, B., Zambonin, L. Landi, L. (2001). Antioxidants and total peroxyl radical-trapping ability of olive and seed oils. J. Agric. Food Chem., 49, 6026-6032. 

Com oil phenols have been studied with respect to their potential to scavenge the free radicals, the peroxyl radicals, the superoxide radicals, etc. The free radical scavenging activity of the phenolic acids using model free radicals such as l,7-diphenyl-2-picrylhydrazyl radical (DPPH ), or ABTS (2,2 -azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt cation radical) is often measured. TEAC (Trolox equivalent antioxidant capacity), FRAP (Ferric-reducing antioxidant capacity) and TRAP (total-radical-trapping antioxidant parameter) of the com oil are also used in order to obtain additional information, necessary to investigate the relation between the antioxidant intake and the oxidative stress related diseases (Stratil et al., 2008 Ceto et al., 2014 Apak et al., 2007). 

Total radical trapping parameter (TRAP) assay is widely used in investigations and has various modifications [45-48]. This method presumes antioxidants capability to react with peroxyl radical 2.2-azobis (2-amidinopropane) dihydrochloride (AAPH). TRAP modifications differ in methods of registering analytical signal. Most often the final stage of analysis include peroxyl radical AAPH reaction with luminescent (luminol), fluorescent (dichlorofluorescein-diace-tate, DCFH-DA) or other optically active substrate. Trolox is often used as a standard. 

Oxygen radical absorbance capacity (ORAC) and total trapping antioxidant parameter (TRAP) are two ass s based on competition between an antioxidant and a substrate for peroxyl radicals (Cao Prior, 1998 Cabrini et al., 2001). 

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