Journal ArticleDOI
Use of a Free Radical Method to Evaluate Antioxidant Activity
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TLDR
The antiradical properties of various antioxidants were determined using the free radical 2,2-Diphenyl-1-picrylhydrazyl (DPPH*) in its radical form as discussed by the authors.Abstract:
The antiradical activities of various antioxidants were determined using the free radical, 2,2-Diphenyl-1-picrylhydrazyl (DPPH*). In its radical form. DPPH* has an absorption band at 515 nm which dissappears upon reduction by an antiradical compound. Twenty compounds were reacted with the DPPH* and shown to follow one of three possible reaction kinetic types. Ascorbic acid, isoascorbic acid and isoeugenol reacted quickly with the DPPH* reaching a steady state immediately. Rosmarinic acid and δ-tocopherol reacted a little slower and reached a steady state within 30 min. The remaining compounds reacted more progressively with the DPPH* reaching a steady state from 1 to 6 h. Caffeic acid, gentisic acid and gallic acid showed the highest antiradical activities with a stoichiometry of 4 to 6 reduced DPPH* molecules per molecule of antioxidant. Vanillin, phenol, γ-resorcylic acid and vanillic acid were found to be poor antiradical compounds. The stoichiometry for the other 13 phenolic compounds varied from one to three reduced DPPH* molecules per molecule of antioxidant. Possible mechanisms are proposed to explain the experimental results.read more
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Journal ArticleDOI
Natural antioxidants from residual sources.
Andrés Moure,José Manuel Cruz,Daniel Franco,J.Manuel Domı́nguez,Jorge Sineiro,Herminia Domínguez,María José Núñez,J.Carlos Parajó +7 more
TL;DR: In this paper, the authors focus on the extraction of polyphenols from agricultural and industrial wastes, and summarize available data on the factors affecting their antioxidant activity and stability, and, in some cases, the reported major active compounds identified.
Journal ArticleDOI
Assessing antioxidant and prooxidant activities of phenolic compounds.
Lana Fukumoto,G. Mazza +1 more
TL;DR: The antioxidant activity of many phenolic compounds and extracts was comparable to those of synthetic antioxidants using the beta-carotene bleaching and HPLC methods.
Journal ArticleDOI
Antioxidants in fruits and vegetables – the millennium’s health
Charanjit Kaur,H. C. Kapoor +1 more
TL;DR: The potential of fruits and vegetables rich in antioxidants, their health benefits and the eAect of processing on the bioavailability of these nutrients have been highlighted in this article, where some of the important methods used to determine the antioxidant activity.
Journal ArticleDOI
Comparative study of antioxidant properties and total phenolic content of 30 plant extracts of industrial interest using DPPH, ABTS, FRAP, SOD, and ORAC assays.
TL;DR: A significant relationship between antioxidant capacity and total phenolic content was found, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants.
Journal ArticleDOI
Genesis and development of DPPH method of antioxidant assay
Sagar B. Kedare,Rashmi Singh +1 more
TL;DR: A critical review on various developments to the DPPH method is presented, which has undergone various modifications to suit the requirements, even though the basic approach remains same in all of them.
References
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Journal ArticleDOI
Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion
TL;DR: In this paper, the autoxidation of soybean oil in a cyclodextrin emulsion system was studied in the presence of an emulsion stabilizer consisting of polysaccharides such as xanthan, tragacanth gum, and methylcellulose.
Book ChapterDOI
The Mechanism of Antioxidant Action in Vitro
TL;DR: The spontaneous reaction of atmospheric oxygen with organic compounds leads to a number of degradative changes that reduce the lifetime of many products of interest to the chemical industry, especially polymers, as well as causing the deterioration of lipids in foods.
Journal ArticleDOI
Comparison of the Antioxidative Activity of Some Acid-phenols: Structure-Activity Relationship
Journal ArticleDOI
Paradoxical behavior of antioxidants in food and biological systems.
TL;DR: This paper cites the paradoxical actions of antioxidants in processed foods and in living biological systems in the hope that these will lead the interested reader to further substantiation of the paradoxes cited.