oxygen radical


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Related to oxygen radical: Oxygen radical absorbance capacity

radical

 [rad´ĭ-kal]
1. thorough or sweeping; directed to the cause or root of a morbid process.
2. a group of atoms that enters into and goes out of chemical combination without change and that forms one of the fundamental constituents of a molecule.
color radical chromophore.
free radical a radical that carries an unpaired electron; such radicals are extremely reactive, with a very short half-life.
oxygen radical a toxic metabolite of oxygen, such as superoxide or singlet oxygen, capable of damaging microorganisms and normal tissues.

oxygen radical

Reactive oxygen metabolite Any molecule with an unpaired electron in its outer orbital which leads to an unstable and/or short half-life, which is capable of reducing or oxidizing other molecules. See Oxygen free radicals.

oxygen radical

Hydrogen peroxide (H2O2) or the superoxide radical (O2) produced by the incomplete reduction of oxygen. Oxygen free radicals are released during the respiratory burst phase of phagocytosis by neutrophils and macrophages during inflammation. They cause direct cell damage, increase vascular permeability through damage to the capillary endothelium, and promote chemotaxis. Oxygen free radicals are normally contained by antioxidant protective measures; however, with severe inflammation they cause significant damage. They are believed to be responsible for much of the cellular damage involved in adult respiratory distress syndrome (ARDS), in which massive neutrophil aggregation and phagocytosis occur.
See also: radical
References in periodicals archive ?
Analysis of antioxidant activities of common vegetables employing oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays: a comparative study.
Attacked by oxygen radicals, ultraviolet light, and other toxic agents, it suffers damage in the form of deletions, or deleted sections, and mutations, or changes in the sequence of DNA bases that make up the genetic code.
Excessive production of oxygen radicals and/or a concurrent deficiency of molecules that can eliminate these radicals (i.
Chemiluminescence also was used to detect effects of the herbs on the generation of oxygen radicals in biopsy samples from patients with ulcerative colitis.
Collectively these observations suggest that anti-inflammatory activity of Curcuma longa may be due to its effect on pro-inflammatory cytokine as well as its capacity to scavenge oxygen radicals.
In another animal model of oxygen radical formation, ischemia-reperfusion of rat liver was noted to induce HO-1 and to promote production of biotripyrrins (6).
A lot of laboratory research suggests that oxygen radical accumulation--which is known to increase with aging--is not a good thing to have around if you want to prevent neurodegenerative disease," says Steven Ferris of New York University.
One end of the band corresponds to the emission frequency of hydrogen, 1,420 Mhz, and the other the frequency of the bonded hydrogen and oxygen radical OH, 1,600 Mhz.
Bloomer and scientists from the University of Memphis showed Ambrotose AO capsules (four capsules/day for three weeks) significantly increased two measures of antioxidant capacity -- Oxygen Radical Absorbance Capacity (ORAC) and Trolox Equivalent Antioxidant Capacity (TEAC) -- in the blood of 25 healthy men and women at rest.
The oxygen radical absorbance capacity values, chlorophyll and carotenoid levels were generally greater in the high-quality teas than in the lower-quality teas.
Serum oxygen radical absorbance capacity, plasma protein carbonyls, urinary F(2)-isoprostanes, and resistance of LDL to ex vivo oxidation were measured before and after supplementation as markers of antioxidant status and oxidative stress.
Mystic Harvest's Authentic Tortilla Chips with Sea Salt and Multi-Grain Tortilla Chips contains 25% more antioxidants than a serving of blueberries based on their Oxygen Radical Absorbance Capacity (ORAC) score, according to the company.