Results 351 to 360 of about 251,789 (396)

DPPH antioxidant assay revisited

Food Chemistry, 2009
Abstract Scavenging of DPPH free radical is the basis of a common antioxidant assay. A number of protocols have been followed for this assay resulting in variation in the results of different laboratories. We present a perspective of the protocols followed by different workers with incongruity in their results and recommend a standard procedure ...
Om P. Sharma, T.K. Bhat
openaire   +3 more sources

The effects of DPPH on cochlear microcirculation

Current Medical Science, 2003
To investigate the effects of free radical, 1, 1-Diphenyl-2-picylhydrazyl(DPPH), on cochlear blood flow.Twenty guinea pigs were divided into 3 groups at random, 6 for control group, 6 for 1 mmol/L of DPPH group and 8 for 0.1 mmol/L of DPPH group. 2 microliters vehicle or drugs were dropped into round window membrane.
Kong Weijia, Chen Min
openaire   +4 more sources

Use of DPPH⋅|DPPH Redox Couple for Biamperometric Determination of Antioxidant Activity

Electroanalysis, 2005
AbstractA novel electrochemical method for selective determination of antioxidant activity based on 2,2‐diphenyl‐1‐picrylhydrazyl | 2,2‐diphenyl‐1‐picrylhydrazin (DPPH⋅|DPPH) redox couple and biamperometric technique is proposed. Two identical glassy carbon disk electrodes were mounted in a classic electrochemical cell and the tested working potential ...
Damir Iveković, Stjepan Milardović, Vlatko Rumenjak, Božidar S. Grabarić   +3 more
openaire   +2 more sources

Adaptation of DPPH Method for Antioxidant Determination [PDF]

ECS Transactions, 2011
Antioxidants are indispensable molecules that help prevent biomolecule oxidation. By fighting the production of free radicals, antioxidants prevent different ageing-associated diseases. In this work, the method of 2,2-diphenyl-2-picrilhydracil (DPPH) is adapted to determine antioxidants in different cosmetic, nutritional, and biological samples using ...
Georgina Alarcón-Ángeles, Gisela I. Rodríguez Cid de León, M. Hernández, José Raúl Medina López, Adriana Morales Pérez, Adriana Miriam Domínguez Ramírez   +5 more
openaire   +1 more source

Oxidation of Catechols and Flavonoids by DPPH·

Journal of the Chinese Chemical Society, 2010
AbstractThe reaction of a series of catechols and dpph· has been studied in the methanol solution. The reaction underwent a two electron oxidation with the formation of quinone products. Detailed kinetic study shows that the rate law of the reaction involves the rate determining step of one‐electron oxidation of the catechols to form the corresponding ...
Wei-Lin Chen, Lu-Ming Lin, Andrew Yeh, Wei-Shuen Li   +3 more
openaire   +2 more sources

X-ray Photoelectron Spectra of DPPH and Diphenylpicrylhydrazine [PDF]

Nature Physical Science, 1971
THE technique of X-ray photoelectron spectroscopy (ESCA) is already proving to be a valuable new tool for investigating a variety of problems in chemistry and physics. It entails direct measurement of the binding energies of electrons in the inner shells of the atoms in a molecule and the results have revealed the existence of a chemical shift1–3.
H. Harker, I. W. Drummond
openaire   +2 more sources

DPPH free-radical scavenging activity, total phenolic contents and chemical composition analysis of forty-two kinds of essential oils

Journal of Food and Drug Analysis, 2020
Forty-two commonly used essential oils were investigated for the antioxidant capabilities by DPPH free-radical scavenging activity, total phenolic contents and photochemiluminescence (PCL) assay.
Lin ChiaWen, Yu ChiaWen, Wu SungChuan, Yih KuangHway   +3 more
semanticscholar   +1 more source

Comparative study of antioxidant properties and total phenolic content of 30 plant extracts of industrial interest using DPPH, ABTS, FRAP, SOD, and ORAC assays.

Journal of Agricultural and Food Chemistry, 2009
Aqueous extracts of 30 plants were investigated for their antioxidant properties using DPPH and ABTS radical scavenging capacity assay, oxygen radical absorbance capacity (ORAC) assay, superoxide dismutase (SOD) assay, and ferric reducing antioxidant ...
Stéphanie Dudonné, X. Vitrac, Philippe Coutière, Marion Woillez, J. Mérillon   +4 more
semanticscholar   +1 more source

DPPH as a Standard for High-Field EPR

Journal of Magnetic Resonance, 1997
The potential utility of DPPH as a standard sample for and dissolved, DPPH is reasonably stable in the air at ordi-high-field EPR (electron paramagnetic resonance) is dis- nary temperatures, and under certain limitations can be em-cussed. CW-EPR spectra of solid and dissolved DPPH sam- ployed as a convenient intensity andg-factor standard (2).ples were ...
Louis-Claude Brunel, J. Krzystek, Andrzej Sienkiewicz, Luca Pardi   +3 more
openaire   +3 more sources