Electron Spin Resonance as a Powerful Tool for Studying Antioxidants and Radicals

Barriga-González, Germán; Aguilera‐Venegas, Benjamín; Folch-Cano, Christian; Pérez-Cruz, Fernanda; Olea‐Azar, Claudio

doi:10.2174/09298673113209990157

Cited by 16 publications

(10 citation statements)

References 157 publications

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“…It is interesting to mention the fact that electrochemical [243][244][245][246][247][248][249] and ESR [250] methods are increasingly being applied to the determination of antioxidant capacity. The kind of technology and free radical generator or oxidant influences the antioxidant capacity measurement.…”

Section: Flavonoids -From Biosynthesis To Human Healthmentioning

confidence: 99%

Antioxidant Capacity of Anthocyanin Pigments

Martín¹,

Kuskoski²,

Navas³

et al. 2017

Flavonoids - From Biosynthesis to Human Health

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Anthocyanins are a family of natural pigments classified into the group of flavonoids, considered to be responsible for the color and taste of many fruits and vegetables, i.e. berries. Anthocyanins are common components of the human diet. Besides their interest as colorant because of their coloring properties, the study of anthocyanin compounds stems from their wide applicability in the prevention and even in the treatment of various human diseases. However, various aspects of the pharmacological roles of anthocyanins remain in the dark, having still several obstacles to the development of robust diets or prescribing lines on consumption of anthocyanins. The chemical structure of anthocyanins determines in large measure its capacity and efficacy as an antioxidant agent. In this study, the following aspects are reviewed: the antioxidant effect of anthocyanin pigments; the oxidative stress, the bioavailability after intake and biological aspects of anthocyanins, the method for measuring the antioxidant activity of anthocyanins, the relationship between structure and activity; and the influence of the anthocyanins in the antioxidant activity of wines. Finally an overview of some potential uses in food industry is attempted mainly focusing in the anthocyanin encapsulation topic. Attention has been paid to the more recent publications in the field.

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Section: Flavonoids -From Biosynthesis To Human Healthmentioning

confidence: 99%

Antioxidant Capacity of Anthocyanin Pigments

Martín¹,

Kuskoski²,

Navas³

et al. 2017

Flavonoids - From Biosynthesis to Human Health

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“…Therefore, EPR has wide application for the analysis of free radical generation in vitro, and also for the measurement of radical scavenging activity of plant extracts in aqueous solution without color interference. 17) In this study, the free radical scavenging activity of curcumin and its demethoxy derivatives (demethoxycurcumin (Dmc) and bisdemethoxycurcumin (Bdmc)) and hydrogenated derivatives (tetrahydrocurcumin (THC), hexahydrocurcumin (HHC) and octahydrocucumin (OHC)) towards DPPH radical, nitric oxide, hydroxyl radical, superoxide anion radical, was investigated. As EPR spectroscopy only detects molecules or atoms with unpaired electrons, the concentrations of free radicals (or spin) could be simply calculated from the area under the peak of the EPR spectrum.…”

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confidence: 99%

Electron Paramagnetic Resonance Study of the Free Radical Scavenging Capacity of Curcumin and Its Demethoxy and Hydrogenated Derivatives

Morales

Sirijaroonwong

Yamanont

et al. 2015

Biological & Pharmaceutical Bulletin

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The quantitative free radical scavenging capacity of curcumin and its demethoxy derivatives (demethoxycurcumin (Dmc) and bisdemethoxycurcumin (Bdmc)) and hydrogenated derivatives (tetrahydrocurcumin (THC), hexahydrocurcumin (HHC) and octahydrocurcumin (OHC)) towards 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide radical (NO), hydroxyl radical (HO · ) and superoxide anion radical (O 2 · ) were investigated by electron paramagnetic resonance (EPR) spectroscopy. One mole of the hydrogenated derivatives scavenged about 4 mol of the DPPH radical, while curcumin and Dmc scavenged about 3 mol of the DPPH radical. Curcumin and THC showed moderate scavenging activity towards NO, yielding 200 mmol of NO scavenged per 1 mol of the scavenger. In contrast, curcumin and its derivatives showed very low scavenging activity towards HO · and O 2 · , yielding approximately only 3-12 mmol scavenged per 1 mol of the tested compounds. Our results suggest that curcumin and its derivatives principally act as chain breaking antioxidants rather than as direct free radical scavengers. Furthermore, we showed that the ortho-methoxyphenolic group and the heptadione linkage of these molecules greatly contributed to their DPPH and NO scavenging activity.Key words curcumin; electron paramagnetic resonance; free radical scavenger; spin trapping Curcumin [1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione] is the primary biologically active constituent that is isolated from the spice, turmeric (Curcuma longa LINN). It shows various therapeutically beneficial activities, including anti-oxidant, anti-inflammatory, anti-cancer, and anti-viral activities 1,2) mediated through its interactions with several molecular targets such as enzymes, receptors, and transcription factors.3,4) As a potent anti-oxidant, several mechanisms have been proposed which describe the direct interaction of curcumin with reactive oxygen species (ROS) as well as its involvement in ROS-independent mechanisms (i.e., induction of antioxidant enzymes). 5,6) The structure-antioxidant activity relationship of curcumin and the compound it reduces has been demonstrated in both in vitro and in vivo models, for example, 1,1-diphenyl-2-picrylhydrazyl (DPPH) kinetic analysis, γ-radiolysis of rat liver microsomes, 7) 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH)-induced low density lipoprotein (LDL) oxidation, 8) AAPH-induced linoleic oxidation. 9) Lastly, the protective effects of curcumin on oxidative injury have been demonstrated in vivo in several animal diseases models. [10][11][12] Free radicals are normally formed by the physiological processes of the cell. For example superoxide anion radical (O 2 −· ) is produced during the mitochondrial respiratory chain reaction and the nitric oxide radical (NO) is generated by the activation of nitric oxide synthase. In some circumstances, the overproduction of those radicals, as well as the formation of toxic radicals such as the hydroxyl radical (HO · ) leads to the damage of biological molecules, thus resulting in many ...

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“…The DPPH radical scavenging activity assay measures the losses in absorption when DPPH radical is reduced by an antioxidant or free radical species (Brand-Williams, Cuvelier, & Berset, 1995). The antioxidant content and total antioxidant activity have been also evaluated electrochemically, by means of voltammetric, amperometric, or electron spin resonance methods (Barriga-González, Aguilera-Venegas, Folch-Cano, Pérez-Cruz, & Olea-Azar, 2013;Blasco, Gonzalez, & Escarpa, 2004;Pisoschi, Cheregi, & Danet, 2009;Yang et al, 2013). Specific methods and techniques detection limit of about five times to one order of magnitude for antioxidant capacity assessment and was successfully applied to the determination of the TAC in fruit-based juices (Yang et al, 2013).…”

Section: Antioxidant Properties: Study Approachmentioning

confidence: 99%

Fruit‐based juices: Focus on antioxidant properties—Study approach and update

Durazzo

Lucarini

Novellino

et al. 2019

Phytotherapy Research

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This paper proposes a perspective literature review of the antioxidant properties in fruit‐based juices. The total antioxidant properties due to compounds such as carotenoids, polyphenolic compounds, flavonoids, and tannins as well as the assessment of interactions between natural active compounds and other food matrix components can be seen as the first step in the study of potential health benefits of fruit‐based juices. A brief summary is given on the significance of antioxidant properties of fruit juices, the conventional methods for antioxidant activity evaluation, and on the newly emerged sample analysis and data interpretation strategies, that is, chemometric analysis based on spectroscopic data. The effect of fruit processing techniques and the addition of ingredients on the antioxidant properties of fruit‐based juices are also discussed.

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Electron Spin Resonance as a Powerful Tool for Studying Antioxidants and Radicals

Cited by 16 publications

References 157 publications

Antioxidant Capacity of Anthocyanin Pigments

Antioxidant Capacity of Anthocyanin Pigments

Electron Paramagnetic Resonance Study of the Free Radical Scavenging Capacity of Curcumin and Its Demethoxy and Hydrogenated Derivatives

Fruit‐based juices: Focus on antioxidant properties—Study approach and update

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