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Srinivas S, Senthil Kumar A. Electrical Wiring of Malarial Parasite Intermediate Hematin on a Tailored N-Doped Carbon Nanomaterial Surface and Its Bioelectrocatalytic Hydrogen Peroxide Reduction and Sensing. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:10634-10647. [PMID: 38723623 DOI: 10.1021/acs.langmuir.4c00583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Hematin, an iron-containing porphyrin compound, plays a crucial role in various biological processes, including oxygen transport, storage, and functionality of the malarial parasite. Specifically, hematin-Fe interacts with the nitrogen atom of antimalarial drugs, forming an intermediate step crucial for their function. The electron transfer functionality of hematin in biological systems has been scarcely investigated. In this study, we developed a biomimicking electrical wiring of hematin-Fe with a model N-drug system, represented as {hematin-Fe---N-drug}. We achieved this by immobilizing hematin on a multiwalled carbon nanotube (MWCNT)/N-graphene quantum dot (N-GQD) modified electrode (MWCNT/N-GQD@Hemat). N-GQD serves as a model molecular drug system containing nitrogen atoms to mimic the {hematin-Fe---N-drug} interaction. The prepared bioelectrode exhibited a distinct redox peak at a measured potential (E1/2) of -0.410 V vs Ag/AgCl, accompanied by a surface excess value of 3.54 × 10-9 mol cm-2. This observation contrasts significantly with the weak or electroinactive electrochemical responses documented in literature-based hematin systems. We performed a comprehensive set of physicochemical and electrochemical characterizations on the MWCNT/N-GQD@Hemat system, employing techniques including FESEM, TEM, Raman spectroscopy, IR spectroscopy, and AFM. To evaluate the biomimetic electrode's electroactivity, we investigated the selective-mediated reduction of H2O2 as a model system. As an important aspect of our research, we demonstrated the use of scanning electrochemical microscopy to visualize the in situ electron transfer reaction of the biomimicking electrode. In an independent study, we showed enzyme-less electrocatalytic reduction and selective electrocatalytic sensing of H2O2 with a detection limit of 319 nM. We achieved this using a batch injection analysis-coupled disposable screen-printed electrode system in physiological solution.
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Affiliation(s)
- Sakthivel Srinivas
- Nano and Bioelectrochemistry Research Laboratory, Carbon Dioxide Research and Green Technology Centre, Vellore 632014, India
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, India
| | - Annamalai Senthil Kumar
- Nano and Bioelectrochemistry Research Laboratory, Carbon Dioxide Research and Green Technology Centre, Vellore 632014, India
- Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore 632 014, India
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Hawkins CL, Davies MJ. Detection and characterisation of radicals in biological materials using EPR methodology. Biochim Biophys Acta Gen Subj 2014; 1840:708-21. [DOI: 10.1016/j.bbagen.2013.03.034] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 03/28/2013] [Indexed: 12/21/2022]
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Minakata K, Iwahashi H. Identification of a radical formed in the reaction mixtures of ram seminal vesicle microsomes with arachidonic Acid using high performance liquid chromatography-electron spin resonance spectrometry and high performance liquid chromatography-electron spin resonance-mass spectrometry. J Clin Biochem Nutr 2010; 46:135-9. [PMID: 20216946 PMCID: PMC2831092 DOI: 10.3164/jcbn.09-90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 11/06/2009] [Indexed: 11/22/2022] Open
Abstract
The reaction of ram seminal vesicle (RSV) microsomes with arachidonic acid (AA) was examined using electron spin resonance (ESR), high performance liquid chromatography-electron spin resonance spectrometry (HPLC-ESR), and high performance liquid chromatography-electron spin resonance-mass spectrometry (HPLC-ESR-MS) combined use of spin trapping technique. A prominent ESR spectrum (alpha(N) = 1.58 mT and alpha(H)beta = 0.26 mT) was observed in the complete reaction mixture of ram seminal vesicle microsomes with arachidonic acid containing 2.0 mg protein/ml ram seminal vesicle (RSV) microsomal suspension, 0.8 mM arachidonic acid, 0.1 M 4-POBN, and 24 mM tris/HCl buffer (pH 7.4). The ESR spectrum was hardly observed for the complete reaction mixture without the RSV microsomes. The formation of the radical appears to be catalyzed by the microsomal components. In the absence of AA, the intensity of the ESR signal decreased to 16 +/- 15% of the complete reaction mixture, suggesting that the radical is derived from AA. For the complete reaction mixture with boiled microsomes, the intensity of the ESR signal decreased to 49 +/- 4% of the complete reaction mixture. The intensity of the ESR signal of the complete reaction mixture with indomethacin decreased to 74 +/- 20% of the complete reaction mixture, suggesting that cyclooxygenese partly participates in the reaction. A peak was detected on the elution profile of HPLC-ESR analysis of the complete reaction mixture. To determine the structure of the peak, an HPLC-ESR-MS analysis was performed. The HPLC-ESR-MS analysis of the peak showed two prominent ions, m/z 266 and m/z 179, suggesting that the peak is a 4-POBN/pentyl radical adduct. An HPLC-ESR analysis of the authentic 4-POBN/pentyl radical adduct comfirmed the identification.
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Affiliation(s)
- Katsuyuki Minakata
- Department of Chemistry, Wakayama Medical University, 580 Mikazura, Wakayama 641-0011, Japan
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Cimpoiu C, Miclaus V, Damian G, Hodisan S. SEPARATION AND IDENTIFICATION OF SOME NITROXIDIC DERIVATIVES OF NICOTINIC ACID AND ISO -NICOTINIC ACID BY HPTLC COUPLED WITH ELECTRONIC PARAMAGNETIC RESONANCE (EPR). J LIQ CHROMATOGR R T 2002. [DOI: 10.1081/jlc-120005701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Claudia Cimpoiu
- a Faculty of Chemistry and Chemical Engineering , “Babes-Bolyai” University , 11 Arany Janos, Cluj-Napoca , 3400 , Romania
| | - Vasile Miclaus
- a Faculty of Chemistry and Chemical Engineering , “Babes-Bolyai” University , 11 Arany Janos, Cluj-Napoca , 3400 , Romania
| | - Grigore Damian
- b Faculty of Physics , “Babes-Bolyai” University , 1 M. Kogalniceanu, Cluj-Napoca , 3400 , Romania
| | - Sorin Hodisan
- c Faculty of Science , University of Oradea , 5 Armata Romana, Oradea , 3700 , Romania
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Iwahashi H, Nishizaki K, Takagi I. Detection of the radical and reduced forms of α-(4-pyridyl 1-oxide)-N-tert-butylnitrone/pentyl radical adduct formed on reaction of an oxidized linoleic acid with ferrous ions using high performance liquid chromatography with electrochemical detection. J Sep Sci 2002. [DOI: 10.1002/1615-9314(20020601)25:9<601::aid-jssc601>3.0.co;2-i] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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6
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Qian SY, Chen YR, Deterding LJ, Fann YC, Chignell CF, Tomer KB, Mason RP. Identification of protein-derived tyrosyl radical in the reaction of cytochrome c and hydrogen peroxide: characterization by ESR spin-trapping, HPLC and MS. Biochem J 2002; 363:281-8. [PMID: 11931655 PMCID: PMC1222476 DOI: 10.1042/0264-6021:3630281] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The reaction of cytochrome c and H(2)O(2) is known to form a protein-centred radical that can be detected with the spin trap 2-methyl-2-nitrosopropane (MNP). To characterize the MNP/tyrosyl adduct structure that had previously been determined incorrectly [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503], we eliminated unreasonable structure models by ESR studies with a series of (13)C-labelled tyrosines, and photochemically synthesized an authentic MNP/tyrosyl adduct that has its trapping site on the C-3 position of the tyrosine phenyl ring. The observation of the identical ESR spectra for this radical adduct from the UV irradiation of 3-iodo-tyrosine and the adduct from the cytochrome c reaction demonstrated that the radical trapping site of MNP/tyrosyl is located on the equivalent C-3/C-5 positions instead of the C-1 position, as was proposed by Barr et al. In an on-line HPLC/ESR system, an identical retention time (17.7 min) was observed for the ESR-active HPLC peak of the MNP/tyrosyl adduct from the following three reactions: (i) the tyrosine oxidation via horseradish peroxidase/H(2)O(2); (ii) UV irradiation of 3-iodo-tyrosine and (iii) the reaction of cytochrome c with H(2)O(2). This result demonstrated that the radical adducts of all three reactions are most probably the same. The mass spectrometric analysis of the HPLC fractions from reactions (i) and (ii) showed an ion at m/z 267 attributed to the MNP/tyrosyl adduct. We conclude that the cytochrome c-derived tyrosyl radical was trapped by MNP, leading to a persistent radical adduct at the C-3/C-5 positions of the tyrosine phenyl ring.
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Affiliation(s)
- Steven Yue Qian
- Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, Research Triangle Park, NC 27709, U.S.A.
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Iwahashi H. High-performance liquid chromatographic determination of linoleic acid peroxide-derived radicals using electrochemical detection. J Chromatogr A 2000; 904:197-202. [PMID: 11204234 DOI: 10.1016/s0021-9673(00)00925-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High-performance liquid chromatography-electrochemical detection (HPLC-ED) was applied to detect 13-hydroperoxide octadecadienoic acid (13-HPODE)-derived radicals such as the pentyl radical and octanoic acid radical. The 13-HPODE-derived radicals were successfully detected using HPLC-ED by the combined use of the spin-trapping technique with alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN). The 4-POBN-pentyl radical adduct was detected at the retention time of 18.2 +/- 0.3 min on the elution profile of HPLC-ED with an ODS column (15 cm x 4.6 mm I.D.) using a flow-rate of 1.0 ml/min with 50 mM ammonium acetate in 29% (v/v) aqueous acetonitrile. The 4-POBN-octanoic acid radical adduct was also detected at the retention time of 13.7 +/- 0.7 min using a flow-rate of 1.0 ml/min with 50 mM ammonium acetate in 14% (v/v) aqueous acetonitrile. The concentrations of the 4-POBN radical adducts were determined using HPLC-ED without an internal standard. HPLC-ED is 100 times as sensitive as HPLC-electron spin resonance (ESR) under the ESR and ED conditions employed here. Even 1.8 pmol of the 4-POBN-pentyl (or octanoic acid) radical adduct was detectable using
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Affiliation(s)
- H Iwahashi
- Department of Chemistry, Wakayama Medical College, Japan.
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8
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Detection of the oxidative products of 3-hydroxykynurenine using high-performance liquid chromatography–electrochemical detection–ultraviolet absorption detection–electron spin resonance spectrometry and high-performance liquid chromatography–electrochemical detection–ultraviolet absorption detection–mass spectrometry. J Chromatogr A 1997. [DOI: 10.1016/s0021-9673(97)00271-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Quantitative detection of reduced, radical and oxidized forms of α-(4-pyridyl-1-oxide)-N-tert.-butylnitrone radical adduct using high-performance liquid chromatography with electrochemical detection. J Chromatogr A 1996. [DOI: 10.1016/s0021-9673(96)00532-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Iwahashi H, Deterding LJ, Parker CE, Mason RP, Tomer KB. Identification of radical adducts formed in the reactions of unsaturated fatty acids with soybean lipoxygenase using continuous flow fast atom bombardment with tandem mass spectrometry. Free Radic Res 1996; 25:255-74. [PMID: 8889492 DOI: 10.3109/10715769609149051] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Structures of alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) radical adducts formed in the reactions of soybean lipoxygenase with linoleic acid, linolenic acid, and arachidonic acid were determined using continuous flow fast atom bombardment (CF-FAB) combined with tandem mass spectrometry. The radical adducts of these lipoxygenase-dependent reactions were: n-octanoic acid radical, 12,13-dihydroxylinoleic acid radical, 12,13-epoxylinoleic acid radical, and n-pentyl radical from linoleic acid; n-octanoic acid radical, ethyl radical, and cis/trans and/or positional isomers (1- and 3-pentenyl) of pentenyl radical from linolenic acid; and 14,15-epoxyarachidonic acid radical and n-pentyl radical from arachidonic acid. Of these radical adducts, the n-octanoic acid radical from linoleic and linolenic acid, the ethyl radical from linolenic acid, and the 12,13-dihydroxylinoleic acid radical are identified for the first time in the reactions of soybean lipoxygenase. Thus the CF-FAB combined with tandem mass spectrometry employed here, by which both radical adducts and their fragment ions can be detected, is shown to be a powerful tool in the structural identification of free radicals.
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Affiliation(s)
- H Iwahashi
- Department of Chemistry, Wakayama Medical College, Japan
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11
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Janzen EG, Sang H, Kotake Y, Dubose CM, Poyer JL, Arimura M. Tandem mass spectrometry study of C-phenyl-N-tert-butyl nitrone spin adducts from in vitro rat liver microsomal metabolism of bromotrichloromethane and carbon tetrachloride. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 1995; 6:847-853. [PMID: 24214427 DOI: 10.1016/1044-0305(95)00328-b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/1994] [Revised: 04/11/1995] [Accepted: 04/17/1995] [Indexed: 06/02/2023]
Abstract
Electron ionization and thermospray were used in conjunction with tandem mass spectrometry methods to identify trichloromethyl/C-phenyl-N-tert-butyl nitrone (PBN) spin adducts produced in rat liver microsomal dispersions that had been treated with reduced nicotinamide adenine dinucleotide phosphate (NADPH)-generating system and BrCCl3 (or CCl4). In the identification of PBN spin adducts, a scan of precursors of m / z 57 was utilized to confirm the presence of PBN spin adducts, because PBN spin adducts produce m / z 57 from tert-butyl as a characteristic fragment. Use of deuterated PBN (PBN-d9 deuterated at tert-butyl; PBN-d 14 deuterated at both phenyl and tert-butyl) improved the recognition of PBN adducts in mixtures by precursor ion scans, because m / z 66 (which corresponds to the deuterated tert-butyl group) is characteristic and, unlike m / z 57, it is not a common fragment for any other compounds. Two new PBN spin adducts that were not detected before by electron paramagnetic resonance or mass spectrometry were identified by these methods for the first time.
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Affiliation(s)
- E G Janzen
- National Biomedical Center for Spin Trapping and Free Radicals, Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, N.E. 13th Street, Oklahoma City, Oklahoma, USA
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12
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Iwahashi H, Parker CE, Tomer KB, Mason RP. Detection of the ethyl- and pentyl-radical adducts of alpha-(4-pyridyl-1- oxide)-N-tert-butylnitrone in rat-liver microsomes treated with ADP, NADPH and ferric chloride. FREE RADICAL RESEARCH COMMUNICATIONS 1992; 16:295-301. [PMID: 1324207 DOI: 10.3109/10715769209049182] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
HPLC-EPR analyses of the reaction mixtures of microsomal suspensions incubated with ADP, ferric chloride, NADPH and alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) were performed. In the elution pattern of the reaction mixture, three peaks (peaks 1, 2 and 3) were detected. The radical adducts (1 and 3) were identified as being the pentyl- and ethyl-radical adducts of 4-POBN by comparing their retention times with those of the authentic radical adducts.
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Affiliation(s)
- H Iwahashi
- Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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Parker CE, Iwahashi H, Tomer KB. Spin-trapped Radicals: Determination by LC-TSP-MS and LC-ESI-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 1991; 2:413-418. [PMID: 24242692 DOI: 10.1016/1044-0305(91)85007-s] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/1991] [Accepted: 03/25/1991] [Indexed: 06/02/2023]
Abstract
The 4-POBN[α-(4-pyridyl-l-oxide)-N-tert-butyl-nitrone] radical adducts of ethyl and pentyl radicals were determined by a combination of high performance liquid chromatography (HPLC) combined with electron paramagnetic resonance (EPR) with HPLC-electrospray (ESI)-mass spectrometry and HPLC-thermospray (TSP)-MS. The identifIcation of the peak corresponding to the spin-trapped radical was done by performing HPLC-EPR under the same chromatographic conditions as the HPLC-MS. The radical adducts could be determined by both techniques, even though for ESI only 12 μL/min of the total 1 mL/min HPLC flow rate could be directed into the ion source.
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Affiliation(s)
- C E Parker
- Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, P.O. Box 12233, Z7709, Research Triangle Park, NC
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Iwahashi H, Parker CE, Mason RP, Tomer KB. Radical adducts of nitrosobenzene and 2-methyl-2-nitrosopropane with 12,13-epoxylinoleic acid radical, 12,13-epoxylinolenic acid radical and 14,15-epoxyarachidonic acid radical. Identification by h.p.l.c.-e.p.r. and liquid chromatography-thermospray-m.s. Biochem J 1991; 276 ( Pt 2):447-53. [PMID: 1646600 PMCID: PMC1151112 DOI: 10.1042/bj2760447] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Linoleic acid-derived radicals, which are formed in the reaction of linoleic acid with soybean lipoxygenase, were trapped with nitrosobenzene and the resulting radical adducts were analysed by h.p.l.c.-e.p.r. and liquid chromatography-thermospray-m.s. Three nitrosobenzene radical adducts (peaks I, II and III) were detected; these gave the following parent ion masses: 402 for peak I, 402 for peak II, and 386 for peak III. The masses of peaks I and II correspond to the linoleic acid radicals with one more oxygen atom [L(O).]. The radicals are probably carbon-centred, because the use of 17O2 did not result in an additional hyperfine splitting. Computer simulation of the peak I radical adduct e.p.r. spectrum also suggested that the radical is carbon-centred. The peak I radical was also detected in the reaction of 13-hydroperoxylinoleic acid with FeSO4. From the above results, peak I is probably the 12,13-epoxylinoleic acid radical. An h.p.l.c.-e.p.r. experiment using [9,10,12,13-2H4]linoleic acid suggested that the 12,13-epoxylinoleic acid radical is a C-9-centred radical. Peak II is possibly an isomer of peak I. Peak III, which was observed in the reaction mixture without soybean lipoxygenase, corresponds to a linoleic acid radical (L.). The 12,13-epoxylinoleic acid radical, 12,13-epoxylinolenic acid radical and 14,15-epoxyarachidonic acid radical were also detected in the reactions of linoleic acid, linolenic acid and arachidonic acid respectively, with soybean lipoxygenase using nitrosobenzene and 2-methyl-2-nitrosopropane as spin-trapping agents.
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Affiliation(s)
- H Iwahashi
- Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709
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Iwahashi H, Albro PW, McGown SR, Tomer KB, Mason RP. Isolation and identification of alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone radical adducts formed by the decomposition of the hydroperoxides of linoleic acid, linolenic acid, and arachidonic acid by soybean lipoxygenase. Arch Biochem Biophys 1991; 285:172-80. [PMID: 1846731 DOI: 10.1016/0003-9861(91)90346-k] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
alpha-(4-Pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN) radical adducts, which are formed in the reactions of soybean lipoxygenase with linoleic acid, arachidonic acid, and linolenic acid, were isolated using HPLC-ESR spectroscopy. Both linoleic acid and arachidonic acid gave one radical adduct, whereas in the case of linolenic acid, two radical adducts were isolated. These radical adducts all showed virtually identical uv spectra with lambda max at 292 and 220 nm in hexane. The absence of absorbance with lambda max at 234 nm indicates that a conjugated diene structure is not contained in these radical adducts. The mass spectra of the radical adducts formed from linoleic and arachidonic acids were identical and contained a molecular ion of m/z 264, consistent with the trapping of the pentyl radical by 4-POBN. Indeed, authentic 4-POBN pentyl radical adduct obtained from the reaction between pentylhydrazine and 4-POBN gave the same mass spectrum as the product obtained from the reaction of linoleic acid and arachidonic acid with 4-POBN. The two 4-POBN radical adducts formed in the linolenic acid reaction were shown by mass spectrometry to be isomers of pentenyl radicals. The 4-POBN-pentyl radical adduct was also detected in the reaction mixture of 13-hydroperoxy-linoleic acid, soybean lipoxygenase, and 4-POBN, indicating that the pentyl radical and pentenyl radical are formed by the decomposition of the hydroperoxides.
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Affiliation(s)
- H Iwahashi
- Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
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Sugata R, Iwahashi H, Ishii T, Kido R. Separation of polyunsaturated fatty acid radicals by high-performance liquid chromatography with electron spin resonance and ultraviolet detection. JOURNAL OF CHROMATOGRAPHY 1989; 487:9-16. [PMID: 2541151 DOI: 10.1016/s0378-4347(00)83002-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the reaction of soybean lipoxygenase (EC 1.13.11.12) with polyunsaturated fatty acids such as linoleic, linolenic and arachidonic acids, some radical species were detected using the electron spin resonance (ESR) spin-trapping technique. The radical species derived from the three polyunsaturated fatty acids were not distinguishable because the ESR spectra of the spin adducts of nitrosobenzene with their three radical species showed no difference in their hyperfine splittings. To overcome this defect of the spin-trapping technique, these spin-adducts were separated by employing high-performance liquid chromatography (HPLC) combined with ESR spectroscopy. The spin adducts were eluted from a C18 reversed-phase column in the order linolenic acid, linoleic acid and arachidonic acid. The half-lives of the spin adducts separated by HPLC-ESR were determined as linoleic acid 600 min, linolenic acid 360 min and arachidonic acid 160 min. The use of an ultraviolet detector together with the HPLC-ESR technique resulted in a 500-fold increase in sensitivity in the detection of the radical species.
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Affiliation(s)
- R Sugata
- Department of Biochemistry, Wakayama Medical College, Japan
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18
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Davies MJ. Applications of electron spin resonance spectroscopy to the identification of radicals produced during lipid peroxidation. Chem Phys Lipids 1987; 44:149-73. [PMID: 2822269 DOI: 10.1016/0009-3084(87)90048-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Electron spin resonance (ESR) spectroscopy, which is the only commonly available method for directly detecting free radicals in biological systems, has now been quite extensively used to study radicals produced by metabolism of xenobiotic chemicals and the interaction of such species with lipid molecules. This review examines a variety of different xenobiotic systems and tissues and summarises the information obtained from these studies, with particular reference to the elucidation of the nature of the radicals involved in the initiation and propagation of lipid peroxidation.
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Affiliation(s)
- M J Davies
- Biochemistry Department, Brunel University, Uxbridge, Middlesex, U.K
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Iwahashi H, Negoro Y, Ikeda A, Kido R. Detection of some retinoid radicals using high-performance liquid chromatography with electron spin resonance spectroscopy or electrochemical detection. J Chromatogr A 1987; 391:199-205. [PMID: 3034940 DOI: 10.1016/s0021-9673(01)94316-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Radical species were detected in the incubation mixtures of some retinoids (retinoic acid, retinal, retinol and retinyl acetate) by using the spin-trapping technique. The spin-adducts were resolved by high-performance liquid chromatography on a reversed-phase column with isocratic elution and detected by electron spin resonance spectroscopy and electrochemical detection. The spin-adducts were eluted in the order retinoic acid, retinol, retinyl acetate, in a similar manner to the retinoids themselves. These results suggest that the spin-adducts are products of nitrosobenzene with retinoid radicals in which the retinoid radicals retain their original chemical structures.
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Abstract
Spin trapping has become a valuable tool for the study of free radicals in biology and medicine. The electron spin resonance hyperfine splitting constants of spin adducts of interest in this area are tabulated. The entries also contain a brief comment on the source of the radical trapped.
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Affiliation(s)
- G R Buettner
- GSF Forschungszentrum, Institut für Strahlenbiologie, Neuherberg, FRG
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21
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Iwahashi H, Negoro Y, Ikeda A, Morishita H, Kido R. Inhibition by chlorogenic acid of haematin-catalysed retinoic acid 5,6-epoxidation. Biochem J 1986; 239:641-6. [PMID: 3030268 PMCID: PMC1147334 DOI: 10.1042/bj2390641] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Chlorogenic acid (3-O-caffeoylquinic acid) inhibited haematin- and haemoglobin-catalysed retinoic acid 5,6-epoxidation. Some other phenol compounds (caffeic acid and 4-hydroxy-3-methoxybenzoic acid) also showed inhibitory effects on the haematin- and haemoglobin-catalysed epoxidation, but salicylic acid did not. Of the above compounds, caffeic acid and chlorogenic acid were potent inhibitors compared with the other two, suggesting that the o-hydroquinone moiety of chlorogenic acid and caffeic acid is essential to the inhibition of the epoxidation. Although caffeic acid inhibited retinoic acid 5,6-epoxidation requiring the consumption of O2, formation of retinoic acid radicals was not inhibited on the addition of caffeic acid to the incubation mixture. The above results suggest that caffeic acid does not inhibit the formation of retinoic acid radicals but does inhibit the step of conversion of retinoic acid radical into the 5,6-epoxide.
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