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Shoji Y, Terashima Y, Ohkubo K, Ito H, Maruyama K, Fukuzumi S, Nakanishi I. Scandium Ion-Promoted Electron-Transfer Disproportionation of 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-Oxide (PTIO •) in Acetonitrile and Its Regeneration Induced by Water. Int J Mol Sci 2024; 25:4417. [PMID: 38674002 PMCID: PMC11050215 DOI: 10.3390/ijms25084417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/09/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO•), a persistent nitronyl nitroxide radical, has been used for the detection and trapping of nitric oxide, as a redox mediator for batteries, for the activity estimation of antioxidants, and so on. However, there is no report on the reactivity of PTIO• in the presence of redox-inactive metal ions. In this study, it is demonstrated that the addition of scandium triflate, Sc(OTf)3 (OTf = OSO2CF3), to an acetonitrile (MeCN) solution of PTIO• resulted in an electron-transfer disproportionation to generate the corresponding cation (PTIO+) and anion (PTIO-), the latter of which is suggested to be stabilized by Sc3+ to form [(PTIO)Sc]2+. The decay of the absorption band at 361 nm due to PTIO•, monitored using a stopped-flow technique, obeyed second-order kinetics. The second-order rate constant for the disproportionation, thus determined, increased with increasing the Sc(OTf)3 concentration to reach a constant value. A drastic change in the cyclic voltammogram recorded for PTIO• in deaerated MeCN containing 0.10 M Bu4NClO4 was also observed upon addition of Sc(OTf)3, suggesting that the large positive shift of the one-electron reduction potential of PTIO• (equivalent to the one-electron oxidation potential of PTIO-) in the presence of Sc(OTf)3 may result in the disproportionation. When H2O was added to the PTIO•-Sc(OTf)3 system in deaerated MeCN, PTIO• was completely regenerated. It is suggested that the complex formation of Sc3+ with H2O may weaken the interaction between PTIO- and Sc3+, leading to electron-transfer comproportionation to regenerate PTIO•. The reversible disproportionation of PTIO• was also confirmed by electron paramagnetic resonance (EPR) spectroscopy.
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Grants
- JP18K06620 Ministry of Education, Culture, Sports, Science and Technology
- JP20H02779 Ministry of Education, Culture, Sports, Science and Technology
- JP20H04819 Ministry of Education, Culture, Sports, Science and Technology
- JP18H04650 Ministry of Education, Culture, Sports, Science and Technology
- JP17H03010 Ministry of Education, Culture, Sports, Science and Technology
- JP16H02268 Ministry of Education, Culture, Sports, Science and Technology
- JP23K04686 Ministry of Education, Culture, Sports, Science and Technology
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Affiliation(s)
- Yoshimi Shoji
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate (QLMS), National Institutes for Quantum Science and Technology (QST), Chiba-shi 263-8555, Chiba, Japan; (Y.S.); (H.I.)
| | - Yuri Terashima
- Environmental Radiation Effects Research Group, Department of Radiation Measurement and Dose Assessment, Institute for Radiological Science (NIRS), Quantum Life and Medical Science Directorate (QLMS), National Institutes for Quantum Science and Technology (QST), Chiba-shi 263-8555, Chiba, Japan; (Y.T.); (K.M.)
| | - Kei Ohkubo
- Institute for Advanced Co-Creation Studies, Open and Transdisciplinary Research Initiatives, Osaka University, Suita 565-0871, Osaka, Japan;
| | - Hiromu Ito
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate (QLMS), National Institutes for Quantum Science and Technology (QST), Chiba-shi 263-8555, Chiba, Japan; (Y.S.); (H.I.)
| | - Kouichi Maruyama
- Environmental Radiation Effects Research Group, Department of Radiation Measurement and Dose Assessment, Institute for Radiological Science (NIRS), Quantum Life and Medical Science Directorate (QLMS), National Institutes for Quantum Science and Technology (QST), Chiba-shi 263-8555, Chiba, Japan; (Y.T.); (K.M.)
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea;
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571, Ibaraki, Japan
| | - Ikuo Nakanishi
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate (QLMS), National Institutes for Quantum Science and Technology (QST), Chiba-shi 263-8555, Chiba, Japan; (Y.S.); (H.I.)
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Nakanishi I, Shoji Y, Ohkubo K, Ito H, Fukuzumi S. Water-Induced Regeneration of a 2,2-Diphenyl-1-picrylhydrazyl Radical after Its Scandium Ion-Promoted Electron-Transfer Disproportionation in an Aprotic Medium. Molecules 2023; 28:5002. [PMID: 37446663 DOI: 10.3390/molecules28135002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/14/2023] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
A neutral, stable radical, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•), has been frequently used to estimate the activity of antioxidants for more than 60 years. However, the number of reports about the effect of metal ions on the reactivity of DPPH• is quite limited. We have recently reported a unique electron-transfer disproportionation of DPPH• to produce the DPPH cations (DPPH+) and anions (DPPH-) upon the addition of scandium triflate [Sc(OTf)3 (OTf = OSO2CF3)] to an acetonitrile (MeCN) solution of DPPH•. The driving force of this reaction is suggested to be an interaction between DPPH- and Sc3+. In this study, it is demonstrated that the addition of H2O to the DPPH•-Sc(OTf)3 system in MeCN resulted in an increase in the absorption band at 519 nm due to DPPH•. This indicated that an electron-transfer comproportionation occurred to regenerate DPPH•. The regeneration of DPPH• was also confirmed by electron paramagnetic resonance (EPR) spectroscopy. The amount of DPPH• increased with an increasing amount of added H2O to reach a constant value. The detailed mechanism of regeneration of DPPH• was proposed based on the detailed spectroscopic and kinetic analyses, in which the reaction of DPPH+ with [(DPPH)2Sc(H2O)3]+ generated upon the addition of H2O to [(DPPH)2Sc]+ is the rate-determining step.
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Grants
- JP18K06620 Ministry of Education, Culture, Sports, Science and Technology
- JP20H02779 Ministry of Education, Culture, Sports, Science and Technology
- JP20H04819 Ministry of Education, Culture, Sports, Science and Technology
- JP18H04650 Ministry of Education, Culture, Sports, Science and Technology
- JP17H03010 Ministry of Education, Culture, Sports, Science and Technology
- JP16H02268 Ministry of Education, Culture, Sports, Science and Technology
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Affiliation(s)
- Ikuo Nakanishi
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Yoshimi Shoji
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Kei Ohkubo
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
- Institute for Advanced Co-Creation Studies, Open and Transdisciplinary Research Initiatives, Osaka University, Suita 565-0871, Japan
| | - Hiromu Ito
- Quantum RedOx Chemistry Team, Institute for Quantum Life Science (iQLS), Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea
- Department of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571, Japan
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3
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Lanuza J, Postils V, Lopez X. Can aluminum, a non-redox metal, alter the thermodynamics of key biological redox processes? The DPPH-QH 2 radical scavenging reaction as a test case. Free Radic Biol Med 2022; 179:200-207. [PMID: 34973365 DOI: 10.1016/j.freeradbiomed.2021.12.308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/07/2021] [Accepted: 12/20/2021] [Indexed: 11/21/2022]
Abstract
The increased bioavailability of aluminum has led to a concern about its toxicity on living systems. Among the most important toxic effects, it has been proven that aluminum increases oxidative stress in biological systems, a controversial fact, however, due to its non-redox nature. In the present work, we characterize in detail how aluminum can alter redox equilibriums by analyzing its effects on the thermodynamics of the redox scavenging reaction between DPPH., a radical compound often used as a reactive oxygen species model, and hydroquinones, a potent natural antioxidant. For the first time, theoretical and experimental redox potentials within aluminum biochemistry are directly compared. Our results fully agree with experimental reduction and oxidation potentials, unequivocally revealing how aluminum alters the spontaneity of the reaction by stabilizing the reduction of DPPH⋅ to DPPH- and promoting a proton transfer to the diazine moiety, leading to the production of a DPPH-H species. The capability of aluminum to modify redox potentials shown here confirms previous experimental findings on the role of aluminum to interfere with free radical scavenging reactions, affecting the natural redox processes of living organisms.
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Affiliation(s)
- Jose Lanuza
- Polimero eta Material Aurreratuak, Kimika eta Teknologia Saila, Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), 20 018, Donostia-San Sebastián, Spain; Donostia International Physics Center (DIPC), 20 018, Donostia-San Sebastián, Spain
| | - Verònica Postils
- Polimero eta Material Aurreratuak, Kimika eta Teknologia Saila, Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), 20 018, Donostia-San Sebastián, Spain; Donostia International Physics Center (DIPC), 20 018, Donostia-San Sebastián, Spain.
| | - Xabier Lopez
- Polimero eta Material Aurreratuak, Kimika eta Teknologia Saila, Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), 20 018, Donostia-San Sebastián, Spain; Donostia International Physics Center (DIPC), 20 018, Donostia-San Sebastián, Spain.
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Nakanishi I, Shoji Y, Ohkubo K, Fukuhara K, Ozawa T, Matsumoto KI, Fukuzumi S. Effects of reaction environments on radical-scavenging mechanisms of ascorbic acid. J Clin Biochem Nutr 2021; 68:116-122. [PMID: 33879962 PMCID: PMC8046006 DOI: 10.3164/jcbn.20-147] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/11/2020] [Indexed: 11/22/2022] Open
Abstract
The effects of reaction environments on the radical-scavenging mechanisms of ascorbic acid (AscH2) were investigated using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) as a reactivity model of reactive oxygen species. Water-insoluble DPPH• was solubilized by β-cyclodextrin (β-CD) in water. The DPPH•-scavenging rate of AscH2 in methanol (MeOH) was much slower than that in phosphate buffer (0.05 M, pH 7.0). An organic soluble 5,6-isopropylidene-l-ascorbic acid (iAscH2) scavenged DPPH• much slower in acetonitrile (MeCN) than in MeOH. In MeOH, Mg(ClO4)2 significantly decelerated the DPPH•-scavenging reaction by AscH2 and iAscH2, while no effect of Mg(ClO4)2 was observed in MeCN. On the other hand, Mg(ClO4)2 significantly accelerated the reaction between AscH2 and β-CD-solubilized DPPH• (DPPH•/β-CD) in phosphate buffer (0.05 M, pH 6.5), although the addition of 0.05 M Mg(ClO4)2 to the AscH2-DPPH•/β-CD system in phosphate buffer (0.05 M, pH 7.0) resulted in the change in pH of the phosphate buffer to be 6.5. Thus, the DPPH•-scavenging reaction by iAscH2 in MeCN may proceed via a one-step hydrogen-atom transfer, while an electron-transfer pathway is involved in the reaction between AscH2 and DPPH•/β-CD in phosphate buffer solution. These results demonstrate that the DPPH•-scavenging mechanism of AscH2 are affected by the reaction environments.
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Affiliation(s)
- Ikuo Nakanishi
- Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Yoshimi Shoji
- Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Kei Ohkubo
- Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
- Institute for Advanced Co-Creation Studies, Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kiyoshi Fukuhara
- School of Pharmacy, Showa University, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Toshihiko Ozawa
- Nihon Pharmaceutical University, Kitaadachi-gun, Saitama 362-0806, Japan
| | - Ken-ichiro Matsumoto
- Quantitative RedOx Sensing Group, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), Quantum Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea
- Faculty of Science and Engineering, Meijo University, Nagoya, Aichi 468-8502, Japan
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5
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Nakanishi I, Ohkubo K, Ogawa Y, Matsumoto KI, Ozawa T, Fukuzumi S. Aluminium ion-promoted radical-scavenging reaction of methylated hydroquinone derivatives. Org Biomol Chem 2018; 14:7956-61. [PMID: 27492849 DOI: 10.1039/c6ob01470d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effect of the aluminium ion (Al(3+)) on the scavenging reaction of a 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙), as a reactivity model of reactive oxygen species, with hydroquinone (QH2) and its methylated derivatives (MenQH2, n = 1-4) was investigated using stopped-flow and electrochemical techniques in a hydroalcoholic medium. The second-order rate constants (k) for the DPPH˙-scavenging reaction of the hydroquinones increased with the increasing number of methyl substituents. Upon addition of Al(3+), the k values significantly increased depending on the concentration of Al(3+). Such an accelerating effect of Al(3+) on the DPPH˙-scavenging rates of the hydroquinones results from the remarkable positive shift of the one-electron reduction potential (Ered) of DPPH˙ in the presence of Al(3+). These results demonstrate that Al(3+), a strong Lewis acid, can act as a radical-scavenging promoter by stabilising the one-electron reduced species of the radical, although Al(3+) is reported not only to act as a pro-oxidant but also to strongly interact with biomolecules, showing toxicities.
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Affiliation(s)
- Ikuo Nakanishi
- Quantitative RedOx Sensing Team (QRST), Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan.
| | - Kei Ohkubo
- Quantitative RedOx Sensing Team (QRST), Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan. and Division of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan and Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea
| | - Yukihiro Ogawa
- Quantitative RedOx Sensing Team (QRST), Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan. and Graduate School of Advanced Integration Science, Chiba University, Inage-ku, Chiba 263-8522, Japan
| | - Ken-Ichiro Matsumoto
- Quantitative RedOx Sensing Team (QRST), Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Inage-ku, Chiba 263-8555, Japan. and Graduate School of Advanced Integration Science, Chiba University, Inage-ku, Chiba 263-8522, Japan
| | - Toshihiko Ozawa
- Division of Oxidative Stress Research, Showa Pharmaceutical University, Machida, Tokyo 194-8543, Japan
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, Korea and Faculty of Science and Technology, Meijo University, SENTAN, Japan Science and Technology Agency (JST), Nagoya, Aichi 468-8502, Japan
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6
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Mukai K, Nakamura A, Nagaoka SI, Ouchi A, Azuma N. Notable Effects of the Metal Salts on the Quenching Reaction of Singlet Oxygen by α-Tocopherol in Ethanol Solution. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2015. [DOI: 10.1246/bcsj.20150182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Kazuo Mukai
- Department of Chemistry, Faculty of Science, Ehime University
| | - Asuka Nakamura
- Department of Chemistry, Faculty of Science, Ehime University
| | | | - Aya Ouchi
- Department of Chemistry, Faculty of Science, Ehime University
- Quality Control Division, Osaka Delika Foods Co., Ltd
| | - Nagao Azuma
- Department of Chemistry, Faculty of Science, Ehime University
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7
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Salamone M, Carboni G, Mangiacapra L, Bietti M. Binding to Redox-Inactive Alkali and Alkaline Earth Metal Ions Strongly Deactivates the C–H Bonds of Tertiary Amides toward Hydrogen Atom Transfer to Reactive Oxygen Centered Radicals. J Org Chem 2015; 80:9214-23. [DOI: 10.1021/acs.joc.5b01661] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Michela Salamone
- Dipartimento
di Scienze e
Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Giulia Carboni
- Dipartimento
di Scienze e
Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Livia Mangiacapra
- Dipartimento
di Scienze e
Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Massimo Bietti
- Dipartimento
di Scienze e
Tecnologie Chimiche, Università “Tor Vergata”, Via
della Ricerca Scientifica, 1, I-00133 Rome, Italy
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8
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Xiao L, Li F, Li Y, Jia X, Liu L. Kinetic study of carbene polymerization of ethyl diazoacetate by palladium and rhodium catalysts. RSC Adv 2014. [DOI: 10.1039/c4ra05455e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Waki T, Kobayashi S, Matsumoto KI, Ozawa T, Kamada T, Nakanishi I. Effects of ionic radius of redox-inactive bio-related metal ions on the radical-scavenging activity of flavonoids evaluated using photometric titration. Chem Commun (Camb) 2014; 49:9842-4. [PMID: 24030811 DOI: 10.1039/c3cc45124k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mg(2+) enhanced the scavenging activity of (+)-catechin and quercetin against the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙), while Al(3+) decreased their activity. Such effects of Mg(2+) and Al(3+) were not observed for kaempferol. Na(+) and Ca(2+) with large ionic radii showed little effect on the DPPH˙-scavenging activity of these three flavonoids.
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Affiliation(s)
- Tsukasa Waki
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), Inage-ku, Chiba 263-8555, Japan.
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Nakanishi I, Kawashima T, Ohkubo K, Waki T, Uto Y, Kamada T, Ozawa T, Matsumoto KI, Fukuzumi S. Disproportionation of a 2,2-diphenyl-1-picrylhydrazyl radical as a model of reactive oxygen species catalysed by Lewis and/or Brønsted acids. Chem Commun (Camb) 2014; 50:814-6. [DOI: 10.1039/c3cc47819j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Mukai K, Kohno Y, Ouchi A, Nagaoka SI. Notable Effects of Metal Salts on UV–Vis Absorption Spectra of α-, β-, γ-, and δ-Tocopheroxyl Radicals in Acetonitrile Solution. The Complex Formation between Tocopheroxyls and Metal Cations. J Phys Chem B 2012; 116:8930-41. [DOI: 10.1021/jp305039z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kazuo Mukai
- Department of Chemistry, Faculty
of Science, Ehime University, Matsuyama
790-8577, Japan
| | - Yutaro Kohno
- Department of Chemistry, Faculty
of Science, Ehime University, Matsuyama
790-8577, Japan
| | - Aya Ouchi
- Department of Chemistry, Faculty
of Science, Ehime University, Matsuyama
790-8577, Japan
| | - Shin-ichi Nagaoka
- Department of Chemistry, Faculty
of Science, Ehime University, Matsuyama
790-8577, Japan
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