In Vitro Electron Paramagnetic Resonance (EPR) Spectroscopy Study on Radical Scavenging Abilities of an Extract Isolated from Stem Bark of Piptadeniastrum africanum Tree

Electron paramagnetic resonance (EPR) spectroscopy can be applied as an effective and non-invasive spectroscopic method for analyzing samples with unpaired electrons. EPR is suitable for the quantification of radical species, assessment of redox chemical reaction mechanisms in foods, evaluation of the antioxidant capacity of food, as well as for the analysis of food quality, stability, and shelf life. It can be employed for evaluating and monitoring the drug release processes, in vitro and in vivo. EPR can be employed for the direct detection of free radical metabolites, and the evaluation of drug release mechanisms from biodegradable polymers; it can be employed for analyzing the drug antioxidant effects. Additionally, spatial resolution can be achieved through EPR-imaging. EPR spectroscopy and imaging have shown diverse applications in food, biomedical and pharmaceutical fields, and also more applications are predictable to emerge in the future. This review highlights recent advances and important challenges related to the application of EPR in food, biomedical and pharmaceutical analysis and assessment.

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ДИНИТРОЗИЛЬНЫЕ КОМПЛЕКСЫ ЖЕЛЕЗА C ТИОЛСОДЕРЖАЩИМИ ЛИГАНДАМИ ПРЕДСТАВЛЕНЫ В ЖИВЫХ ОРГАНИЗМАХ В ОСНОВНОМ ИХ БИЯДЕРНОЙ ФОРМОЙ

Биофизика ◽

10.31857/s0006302920060149 ◽

2020 ◽

Vol 65 (6) ◽

pp. 1142-1153

Author(s):

В.Д. Микоян ◽

◽

Е.Н. Бургова ◽

Р.Р. Бородулин ◽

А.Ф. Ванин ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Sodium Nitrite ◽

Iron Complexes ◽

Paramagnetic Resonance ◽

First Case ◽

Dinitrosyl Iron ◽

Electron Paramagnetic ◽

Dinitrosyl Complexes

The number of mononitrosyl iron complexes with diethyldithiocarbamate, formed in the liver of mice in vivo and in vitro after intraperitoneal injection of binuclear dinitrosyl iron complexes with N-acetyl-L-cysteine or glutathione, S-nitrosoglutathione, sodium nitrite or the vasodilating drug Isoket® was assessed by electron paramagnetic resonance (EPR). The number of the said complexes, in contrast to the complexes, formed after nitrite or Isoket administration, the level of which sharply increased after treatment of liver preparations with a strong reducing agent - dithionite, did not change in the presence of dithionite. It was concluded that, in the first case, EPR-detectable mononitrosyl iron complexes with diethyldithiocarbamate in the absence and presence of dithionite appeared as a result of the reaction of NO formed from nitrite with Fe2+-dieth- yldithiocarbamate and Fe3+-diethyldithiocarbamate complexes, respectively. In the second case, mononitrosyl iron complexes with diethyldithiocarbamate appeared as a result of the transition of iron-mononitosyl fragments from ready-made iron-dinitrosyl groups of binuclear dinitrosyl complexes, which is three to four times higher than the content of the mononuclear form of these complexes in the tissue...

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Investigation of Antioxidant Activity of Pomegranate Juices by Means of Electron Paramagnetic Resonance and UV-Vis Spectroscopy

Journal of AOAC International ◽

10.5740/jaoacint.sge4-kozik ◽

2015 ◽

Vol 98 (4) ◽

pp. 866-870 ◽

Cited By ~ 6

Author(s):

Violetta Kozik ◽

Krystyna Jarzembek ◽

Agnieszka Jędrzejowska ◽

Andrzej Bąk ◽

Justyna Polak ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Free Radical ◽

Epr Spectroscopy ◽

Antioxidant Properties ◽

Free Radical Scavenger ◽

Pomegranate Juice ◽

Radical Scavenger ◽

Paramagnetic Resonance ◽

Vis Spectroscopy ◽

Electron Paramagnetic

Abstract Pomegranate fruit (Punica granatum L.) is a source of numerous phenolic compounds, and it contains flavonoids such as anthocyanins, anthocyanidins, cyanidins, catechins and other complexes of flavonoids, ellagitannins, and hydrolyzed tannins. Pomegranate juice shows antioxidant, antiproliferative, and anti-atherosclerotic properties. The antioxidant capacity (TEAC) of the pomegranate juices was measured using electron paramagnetic resonance (EPR) spectroscopy and 1,1-diphenyl-2-picrylhydrazyl (DPPH•) as a source of free radicals, and the total phenolic (TP) content was measured using UV-Vis spectroscopy. All the examined pomegranate juices exhibited relatively high antioxidant properties. The TEAC values determined by means of EPR spectroscopy using Trolox (TE) as a free radical scavenger were in the range of 463.12 to 1911.91 μmol TE/100 mL juice. The TP content measured by the Folin-Ciocalteu method, using gallic acid (GA) as a free radical scavenger, widely varied in the investigated pomegranate juice samples and ranged from 1673.62 to 5263.87 mg GA/1 L juice. The strongest antioxidant properties were observed with the fresh pomegranate juices obtained from the fruits originating from Israel, Lebanon, and Azerbaijan. Correlation analysis of numerical data obtained by means of EPR spectroscopy (TEAC) and UV-Vis spectroscopy (TP) gave correlation coefficient (r) = 0.90 and determination coefficient (r2) = 0.81 (P <0.05).

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