Evaluation of the Total Peroxyl Radical-Scavenging Capacity of Flavonoids: Structure−Activity Relationships

The antioxidant activity of a series of flavonoids against peroxyl radicals generated from thermal homolysis of 2,2‘-azobis-amidinopropane was determined by the Total Oxyradical Scavenging Capacity (TOSC) assay. Seven flavonoids with hydroxy and/or methoxy substitution were analyzed and compared to...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of natural products (Washington, D.C.) Vol. 63; no. 3; pp. 327 - 331
Main Authors:	Dugas, Alton J, Castañeda-Acosta, José, Bonin, Gloria C, Price, Kimberly L, Fischer, Nikolaus H, Winston, Gary W
Format:	Journal Article
Language:	English
Published:	Washington, DC American Chemical Society 01-03-2000 Glendale, AZ American Society of Pharmacognosy
Subjects:	antioxidants binding sites Biological and medical sciences chemical constituents of plants chemical reactions chemical structure flavonoids Flavonoids - chemistry Flavonoids - pharmacology free radicals General and cellular metabolism. Vitamins General pharmacology Medical sciences medicinal plants Peroxides Pharmacognosy. Homeopathy. Health food Pharmacology. Drug treatments Structure-Activity Relationship structure-activity relationships Peroxy radicals Polyphenol Structure activity relation Plant origin Antioxidant Flavonoid In vitro Radical scavenger Medicinal plant
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	The antioxidant activity of a series of flavonoids against peroxyl radicals generated from thermal homolysis of 2,2‘-azobis-amidinopropane was determined by the Total Oxyradical Scavenging Capacity (TOSC) assay. Seven flavonoids with hydroxy and/or methoxy substitution were analyzed and compared to the water-soluble vitamin E analogue Trolox. The most active compound was the flavonol quercetin, followed by its 3-glycoside derivative rutin; these were 7 and 5 times, respectively, better scavengers of peroxyl radical than Trolox. Among the flavones with both hydroxy and methoxy substitution, the most active against peroxyl radicals was the 5,6,4‘-trihydroxy-7,8,3‘-trimethoxyflavone (thymonin), with a TOSC value 1.5 times greater than that of Trolox. The activity of the remaining flavones was in the following relative order: 5,4‘-dihydroxy-6,7,8,3‘-tetramethoxyflavone > 5-hydroxy-3,6,7,3‘,4‘-pentamethoxyflavone (artemetin) > 5,4‘-dihydroxy-3,6,7-trimethoxyflavone > 5,6,7,8,2‘,3‘,4‘,5‘-octamethoxyflavone (agehoustin A). The data suggest a potential role for dietary intake of flavonoid-containing foods in lowering the risk of certain pathophysiologies that have been associated with free-radical-mediated events.
Bibliography:	ark:/67375/TPS-TJLH8S35-9 istex:9749A869725C111050CD2D88C8B6D4DA9D8B1C14 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0163-3864 1520-6025
DOI:	10.1021/np990352n