Simple determination of peroxyl radical-trapping capacity.
A simple spectrophotometric method of determination of peroxyl radical-trapping capacity (PRTC) of body fluids and food products is proposed. In this method, decomposition of 2,2'-azobis(2-amidopropane) hydrochloride (ABAP) is the source of peroxyl and alkoxyl radicals which oxidize 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) to a green cation radical. Antioxidant present in a sample inhibit the reaction; the induction time of the reaction is proposed as a parameter enabling determination of antioxidant content. Standard assay conditions are: 20 mM ABAP and 150 microM ABTS in 0.1 M phosphate buffer, pH 7.0, at 37 degrees C; absorbance is monitored at 414 nm. A 10-min assay allows for determination of the induction time of appropriately diluted sample. As examples of application of this method, PRTC values of several types of beverages are reported.
Bartosz
G
G
Department of Molecular Biophysics, University of Lódź, Poland. gbartosz@biol.uni.lodz.pl
Janaszewska
A
A
Ertel
D
D
Bartosz
M
M
D000434:Alcoholic Beverages; D000578:Amidines / Q000378:metabolism; D000596:Amino Acids / Q000494:pharmacology; D000975:Antioxidants / Q000032:analysis* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000032:analysis / Q000494:pharmacology; D052160:Benzothiazoles; D002839:Chromans / Q000032:analysis / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D005609:Free Radicals; D007202:Indicators and Reagents; D010084:Oxidation-Reduction; D010545:Peroxides / Q000378:metabolism*; D010949:Plasma; D013053:Spectrophotometry; D013451:Sulfonic Acids / Q000378:metabolism*; D013997:Time Factors
D000578:Amidines; D000596:Amino Acids; D000975:Antioxidants; D052160:Benzothiazoles; D002839:Chromans; D005609:Free Radicals; D007202:Indicators and Reagents; D010545:Peroxides; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; C049375:perhydroxyl radical; C046728:2,2'-azobis(2-amidinopropane); D001205:Ascorbic Acid; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D004837:Epinephrine