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Chen Z, Wang M, Fu Y, Yu H, Di D. Preparation of Quercetin Molecularly Imprinted Polymers. Des Monomers Polym 2012. [DOI: 10.1163/156855511x606173] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Zhenbin Chen
- a State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, P. R. China, School of Material Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, P. R. China, Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730050, P. R. China
| | - Meng Wang
- b State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, P. R. China, School of Material Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, P. R. China
| | - Yu Fu
- c State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, P. R. China, School of Material Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, P. R. China;,
| | - Hui Yu
- d State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, P. R. China, School of Material Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, P. R. China
| | - Duolong Di
- e Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730050, P. R. China
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Ajitha MJ, Mohanlal S, Suresh CH, Jayalekshmy A. DPPH radical scavenging activity of tricin and its conjugates isolated from "Njavara" rice bran: a density functional theory study. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:3693-3699. [PMID: 22397636 DOI: 10.1021/jf204826e] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Structural, electronic, and energetic characteristics of tricin, tricin-4'-O-(erythro-β-guaiacylglyceryl)ether (TEGE), and tricin-4'-O-(threo-β-guaiacylglyceryl)ether (TTGE), isolated from "Njavara" rice bran have been studied using DFT to explain their experimentally determined radical scavenging activity (EC(50) values) in comparison with known standards such as quercetin, myricetin, and catechin. Among the three mechanisms proposed for explaining the antioxidant activity, proton coupled-electron transfer (PC-ET), sequential proton loss electron transfer (SPLET), and electron transfer-proton transfer (ET-PT), our results support the second one. The O-H bond dissociation enthalpy (BDE) and the spin density on the oxygen with the radical character are excellent descriptors of radical scavenging activity. BDE (in kcal/mol) increased in the order myricetin (74.6) < quercetin (78.1) < catechin (78.3) < tricin (81.5) < TTGE (90.6) < TEGE (91.1), while the EC(50) increased exponentially with increase in BDE, 20.51, 42.98, 45.07, 90.39, 208.01, and 352.04 μg/mL for myricetin, quercetin, catechin, tricin, TTGE, and TEGE, respectively.
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Affiliation(s)
- Manjaly J Ajitha
- Computational Modeling and Simulation Section, National Institute for Interdisciplinary Science and Technology (NIIST), CSIR, Trivandrum, India
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Yu H, Chen Z, Fu Y, Kang L, Wang M, Du X. Synthesis and optimization of molecularly imprinted polymers for quercetin. POLYM INT 2012. [DOI: 10.1002/pi.4172] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pakade V, Lindahl S, Chimuka L, Turner C. Molecularly imprinted polymers targeting quercetin in high-temperature aqueous solutions. J Chromatogr A 2012; 1230:15-23. [DOI: 10.1016/j.chroma.2012.01.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 01/14/2012] [Accepted: 01/19/2012] [Indexed: 10/14/2022]
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Wu H, Chen M, Fan Y, Elsebaei F, Zhu Y. Determination of rutin and quercetin in Chinese herbal medicine by ionic liquid-based pressurized liquid extraction–liquid chromatography–chemiluminescence detection. Talanta 2012; 88:222-9. [DOI: 10.1016/j.talanta.2011.10.036] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 10/05/2011] [Accepted: 10/16/2011] [Indexed: 11/26/2022]
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Jin R, Li J. Theoretical Study of the Radical Scavenging Activity of Shikonin and Its Derivatives. CHINESE J CHEM 2011. [DOI: 10.1002/cjoc.201100044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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57
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The effect of Cu2+ on interaction between flavonoids with different C-ring substituents and bovine serum albumin: Structure–affinity relationship aspect. J Inorg Biochem 2011; 105:1529-37. [DOI: 10.1016/j.jinorgbio.2011.08.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 08/06/2011] [Accepted: 08/11/2011] [Indexed: 01/21/2023]
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Zhang Y, Shi S, Sun X, Huang K, Chen X, Peng M. Structure-affinity relationship of bovine serum albumin with dietary flavonoids with different C-ring substituents in the presence of Fe3+ ion. Food Res Int 2011. [DOI: 10.1016/j.foodres.2011.06.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Shi S, Zhang Y, Chen X, Peng M. Investigation of flavonoids bearing different substituents on ring C and their cu2+ complex binding with bovine serum albumin: structure-affinity relationship aspects. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:10761-10769. [PMID: 21863893 DOI: 10.1021/jf2027523] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The effects of 1:1 flavonoid-Cu(2+) complexes of four flavonoids with different C-ring substituents, quercetin (QU), luteolin (LU), taxifolin (TA), and (+)-catechin (CA), on bovine serum albumin (BSA) were investigated and compared with corresponding free flavonoids by spectroscopic analysis in an attempt to characterize the chemical association taking place. The results indicated that all of the quenching mechanisms were based on static quenching combined with nonradiative energy transfer. Cu(2+) chelation changed the binding constants for BSA depending on the structures of flavonoids and the detected concentrations. The reduced hydroxyl groups, increased steric hindrance, and hydrophilicity of Cu(2+) chelation may be the main reasons for the reduced binding constants, whereas the formation of stable flavonoid-Cu(2+) complexes and synergistic action could increase the binding constants. The changed trends of critical energy transfer distance (R(0)) for Cu(2+) chelation were contrary to those of binding constants.
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Affiliation(s)
- Shuyun Shi
- School of Chemistry and Chemical Engineering, Central South University , Changsha 410083, People's Republic of China.
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60
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Jin R, Bai Y. Theoretical investigation of the radical scavenging activity of shikonin and acylshikonin derivatives. J Mol Model 2011; 18:1401-8. [PMID: 21761174 DOI: 10.1007/s00894-011-1170-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 06/28/2011] [Indexed: 12/24/2022]
Abstract
The radical scavenging activity of shikonin and acylshikonin derivatives was studied by using density functional theory. The hydrogen bond property of the studied structures was investigated using the atoms in molecules (AIM) theory. It turned out that the hydrogen bond is important for good radical scavenging activity. The hydrogen atom transfer for shikonin and acylshikonin derivatives is difficult to obtain because of the high bond dissociation energy (BDE). However, shikonin and acylshikonin derivatives appear to be good candidates for the one-electron-transfer. The introduction of acyl groups for shikonin decreases the ionization potential (IP) values compared with that of shikonin. The acylshikonin derivatives with 1H-pyrrole, furan, and thiophene groups are expected to be of the highest radical scavenging activity among the compounds investigated in this study. Taking this system as an example, we present an efficient method for the investigation of radical scavenging activity from theoretical point of view.
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Affiliation(s)
- Ruifa Jin
- Department of Chemistry, Chifeng University, Chifeng 024000, China.
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Donato L, Chiappetta G, Drioli E. Surface Functionalization of PVDF Membrane with a Naringin-Imprinted Polymer Layer Using Photo-Polymerization Method. SEP SCI TECHNOL 2011. [DOI: 10.1080/01496395.2011.575429] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Park HR, Liu HB, Shin SC, Park JK, Bark KM. Spectroscopic Properties of Quercetin-3-O-rhamnoside and Quercetin-3-O-rutinoside in Aerosol-OT Reverse Micelles. B KOREAN CHEM SOC 2011. [DOI: 10.5012/bkcs.2011.32.3.981] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Payán-Gómez SA, Flores-Holguín N, Pérez-Hernández A, Piñón-Miramontes M, Glossman-Mitnik D. Computational molecular characterization of the flavonoid rutin. Chem Cent J 2010; 4:12. [PMID: 20569488 PMCID: PMC2904757 DOI: 10.1186/1752-153x-4-12] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 06/22/2010] [Indexed: 11/10/2022] Open
Abstract
In this work, we make use of a model chemistry within Density Functional Theory (DFT) recently presented, which is called M05-2X, to calculate the molecular structure of the flavonoid Rutin, as well as to predict the infrared (IR) and ultraviolet (UV-Vis) spectra, the dipole moment and polarizability, the free energy of solvation in different solvents as an indication of solubility, the HOMO and LUMO orbitals, and the chemical reactivity parameters that arise from Conceptual DFT. The calculated values are compared with the available experimental data for this molecule as a means of validation of the used model chemistry.
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Affiliation(s)
- Sergio A Payán-Gómez
- Departamento de Simulación Computacional y Modelado Molecular, CIMAV, SC, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chih. 31109, México
- Facultad de Ingeniería, Universidad Autónoma de Chihuahua, Nuevo Campus Universitario, Chihuahua, Chih. 31125, México
| | - Norma Flores-Holguín
- Departamento de Simulación Computacional y Modelado Molecular, CIMAV, SC, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chih. 31109, México
| | - Antonino Pérez-Hernández
- Departamento de Simulación Computacional y Modelado Molecular, CIMAV, SC, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chih. 31109, México
| | - Manuel Piñón-Miramontes
- Junta Municipal de Aguas y Saneamiento de Chihuahua, Perif. Ortiz Mena y Av. Politécnico S/N, Colonia Quintas del Sol, Chihuahua, Chih. 31350, México
| | - Daniel Glossman-Mitnik
- Departamento de Simulación Computacional y Modelado Molecular, CIMAV, SC, Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, Chih. 31109, México
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Aparicio S. A systematic computational study on flavonoids. Int J Mol Sci 2010; 11:2017-38. [PMID: 20559499 PMCID: PMC2885091 DOI: 10.3390/ijms11052017] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 04/27/2010] [Accepted: 04/27/2010] [Indexed: 11/29/2022] Open
Abstract
17 selected flavones derivatives, flavonoids, were analyzed through a systematic B3LYP/6-311++G** computational study with the aim of understanding the molecular factors that determine their structural and energetic properties in gas phase. Flavonoids were selected in a systematic way to infer the effect of the number and relative positions of hydroxyl groups on molecular properties. Different conformers for each flavonoid were analyzed and the strength and topology of the intramolecular hydrogen bonds studied through the computation of the corresponding torsional profiles. Atoms in a Molecule, and Natural Bond Orbital methodology was applied to the analysis of charge distribution along the studied molecules, and the intramolecular hydrogen bonds. Molecular shapes were studied through full geometry optimization, and the position of the catechol ring analyzed through dihedral scans.
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Affiliation(s)
- Santiago Aparicio
- Department of Chemistry, University of Burgos, 09001 Burgos, Spain; E-Mail: ; Tel.: +34-947-258-062
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68
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Marković ZS, Mentus SV, Dimitrić Marković JM. Electrochemical and density functional theory study on the reactivity of fisetin and its radicals: implications on in vitro antioxidant activity. J Phys Chem A 2010; 113:14170-9. [PMID: 19954196 DOI: 10.1021/jp907071v] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Antioxidative properties of naturally occurring flavon-3-ol, fisetin, were examined by both cyclic voltammetry and quantum-chemical based calculations. The three voltametrically detectable consecutive steps, reflected the fisetin molecular structure, catecholic structural unit in the ring B, C3-OH, and C7-OH groups in the rings C and A. Oxidation potential values, used as quantitative parameter in determining its oxidation capability, indicated good antioxidative properties found with this molecule. Oxidation of the C3'C4' dixydroxy moiety at the B ring occurred first at the lowest positive potentials. The first oxidation step induced fast intramolecular transformations in which the C3 hydroxy group disappeared and the product of this transformation participated in the second oxidation step. The highest potential of oxidation was attributed to the oxidation of C7 hydroxy group. The structural and electronic features of fisetin were investigated at the B3LYP/6-311++G** level of theory. Particularly, the interest was focused on the C3' and C4'-OH sites in the B ring and on C3-OH site in the C ring. The calculated bond dissociation enthalpy values for all OH sites of fisetin clearly indicated the importance of the B ring and C3' and C4'-OH group. The importance of keto-enol tautomerism has also been considered. The analysis also included the Mulliken spin density distribution for the radicals formed after H removal on each OH site. The results showed the higher values of the BDE on the C7-OH and C3-OH sites.
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Affiliation(s)
- Zoran S Marković
- Department of Biochemical and Medical Sciences, State University of Novi Pazar, Vuka Karadzića bb, Novi Pazar 36300, Republic of Serbia
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69
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Nakayama T, Uno B. Quinone–Hydroquinone π-Conjugated Redox Reaction Involving Proton-coupled Electron Transfer Plays an Important Role in Scavenging Superoxide by Polyphenolic Antioxidants. CHEM LETT 2010. [DOI: 10.1246/cl.2010.162] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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70
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Calliste C, Kozlowski D, Duroux J, Champavier Y, Chulia A, Trouillas P. A new antioxidant from wild nutmeg. Food Chem 2010. [DOI: 10.1016/j.foodchem.2009.05.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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DFT study on the reactivity of OH groups in emodin: structural and electronic features of emodin radicals. MONATSHEFTE FUR CHEMIE 2009. [DOI: 10.1007/s00706-009-0192-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Justino GC, Vieira AJSC. Antioxidant mechanisms of Quercetin and Myricetin in the gas phase and in solution--a comparison and validation of semi-empirical methods. J Mol Model 2009; 16:863-76. [PMID: 19779937 DOI: 10.1007/s00894-009-0583-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/17/2009] [Indexed: 02/03/2023]
Abstract
Flavonoids have long been recognized for their general health-promoting properties, of which their antioxidant activity may play an important role. In this work we have studied the properties of two flavonols, quercetin and myricetin, using semi-empirical methods in order to validate the application of the recent Parametric Model 6 and to understand the fundamental difference between the two molecules. Their geometries have been optimized and important molecular properties have been calculated. The energetic of the possible antioxidant mechanisms have also been analyzed. The two studied flavonols do not differ significantly in their molecular properties, but the antioxidant mechanisms by which they may act in solution can be rather different. Moreover, we also show that the Parametric Model 6 can produce reliable information for this type of compounds.
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Affiliation(s)
- Gonçalo C Justino
- Requimte/CQFB - Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.
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75
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Liu HB, Yu D, Shin SC, Park HR, Park JK, Bark KM. Spectroscopic Properties of Quercetin Derivatives, �Quercetin-3-O-rhamnoside and Quercetin-3-O-rutinoside, in �Hydro-organic Mixed Solvents. Photochem Photobiol 2009; 85:934-42. [DOI: 10.1111/j.1751-1097.2009.00550.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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76
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Tucker G, Robards K. Bioactivity and structure of biophenols as mediators of chronic diseases. Crit Rev Food Sci Nutr 2009; 48:929-66. [PMID: 18949595 DOI: 10.1080/10408390701761977] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Biophenols and their associated activity have generated intense interest. Current topics of debate are their bioavailability and bioactivity. It is generally assumed that their plasma concentrations are insufficient to produce the health benefits previously attributed to their consumption. However, data on localized in vivo concentrations are not available and many questions remain unanswered. Potential mechanisms by which they may exert significant bioactivity are discussed together with structure activity relationships. Biophenols are highly reactive species and they can react with a range of other compounds. Products of their reaction when functioning as antioxidants are examined.
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Affiliation(s)
- Gregory Tucker
- School of Biosciences, University of Nottingham, Loughborough, Leics, UK
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77
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Amat A, Angelis FD, Sgamellotti A, Fantacci S. Theoretical investigation of the structural and electronic properties of luteolin, apigenin and their deprotonated species. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.theochem.2008.07.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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78
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Acid–base chemistry of luteolin and its methyl-ether derivatives: A DFT and ab initio investigation. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.07.098] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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79
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Amat A, Sgamellotti A, Fantacci S. Theoretical Study of the Structural and Electronic Properties of Luteolin and Apigenin Dyes. COMPUTATIONAL SCIENCE AND ITS APPLICATIONS – ICCSA 2008 2008. [DOI: 10.1007/978-3-540-69839-5_87] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Trouillas P, Marsal P, Svobodová A, Vostálová J, Gazák R, Hrbác J, Sedmera P, Kren V, Lazzaroni R, Duroux JL, Walterová D. Mechanism of the antioxidant action of silybin and 2,3-dehydrosilybin flavonolignans: a joint experimental and theoretical study. J Phys Chem A 2008; 112:1054-63. [PMID: 18193843 DOI: 10.1021/jp075814h] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Flavonolignans from silymarin, the standardized plant extract obtained from thistle, exhibit various antioxidant activities, which correlate with the other biological and therapeutic properties of that extract. To highlight the mode of action of flavonolignans as free radical scavengers and antioxidants, 10 flavonolignans, selectively methylated at different positions, were tested in vitro for their capacity to scavenge radicals (DPPH and superoxide) and to inhibit the lipid peroxidation induced on microsome membranes. The results are rationalized on the basis of (i) the oxidation potentials experimentally obtained by cyclic voltammetry and (ii) the theoretical redox properties obtained by quantum-chemical calculations (using a polarizable continuum model (PCM)-density functional theory (DFT) approach) of the ionization potentials and the O-H bond dissociation enthalpies (BDEs) of each OH group of the 10 compounds. We clearly establish the importance of the 3-OH and 20-OH groups as H donors, in the presence of the 2,3 double bond and the catechol moiety in the E-ring, respectively. For silybin derivatives (i.e., in the absence of the 2,3 double bond), secondary mechanisms (i.e., electron transfer (ET) mechanism and adduct formation with radicals) could become more important (or predominant) as the active sites for H atom transfer (HAT) mechanism are much less effective (high BDEs).
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Affiliation(s)
- Patrick Trouillas
- Laboratoire de Biophysique, Université de Limoges, 2 rue du Docteur Marcland, 87025 Limoges, France.
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Chebil L, Anthoni J, Humeau C, Gerardin C, Engasser JM, Ghoul M. Enzymatic acylation of flavonoids: effect of the nature of the substrate, origin of lipase, and operating conditions on conversion yield and regioselectivity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:9496-9502. [PMID: 17937478 DOI: 10.1021/jf071943j] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The conversion yield at equilibrium, the initial rate, and the regioselectivity of the enzymatic acetylation of aglycone flavonoids (quercetin, naringenin, hesperetin, and chrysin) were investigated and compared to those obtained with a glycosylated one (isoquercitrin). The effects of a wide range of operating conditions were quantified. Fourier transform infrared spectrometry (FT-IR), NMR, and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) analyses showed that for glycosylated flavonoids, in the presence of Candida antarctica (CAL-B), the acetylation occurred on the 2''-OH, 3''-OH, and 6''-OH of the glucose part, while with Pseudomonas cepacea lipase (PSL-C) acetylation takes place on 6''-OH of the sugar and 4'-OH of the B-ring. For aglycone flavonoids, the acetylation occurred only with PSL-C on 4'-OH, 3'-OH, and 7-OH hydroxyls. The conversion yield and the number and the relative proportions of the synthesized products were found dependent on the nature of the enzyme, the molar ratio, and the flavonoid structure. The initial rate was affected only by the origin of the enzyme.
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Affiliation(s)
- Latifa Chebil
- Laboratoire Biocatalyse Bioprocédés, ENSAIA-INPL, Nancy-Université, 2, Av de la Forêt de Haye 54500, Vandoeuvre, France
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Abstract
A complete conformational analysis on the isolated and polarizable continuum model (PCM) modeled aqueous solution cation, quinonoidal, and anion forms of pelargonidin, comprising the diverse tautomers of the latter forms, was carried out at the B3LYP/6-31++G(d,p) level. The results indicate that the most stable conformer of cationic and quinonoidal forms of pelargonidin are completely planar in the gas phase, whereas that of the anionic form is not planar. In contrast, PCM calculations show that the plane of the B ring is slightly rotated with regard to the AC bicycle in the most stable conformer of the cation and quinonoidal form. The most stable conformers of the cation, both in gas phase and aqueous solution, display anti and syn orientations for, respectively, C2-C3-O-H and C6-C5-O-H dihedral angles, whereas syn and anti orientation of hydroxyls at 7 and 4' positions are nearly isoenergetic. The most stable tautomer of quinonoidal pelargonidin is obtained by deprotonating hydroxyl at C5 in gas phase but at C7 according to PCM. Also, the most stable tautomer of the anion is different in gas phase (hydrogens are abstracted from hydroxyls at C5 and C4') and PCM simulation (C3 and C5). Tautomeric equilibria affect substantially the geometries of the AC-B backbone providing bond length variations that basically agree with the predictions of the resonance model. Most of the conformers obtained display an intramolecular hydrogen bond between O3 and H6'. Nevertheless, this interaction is not present in the most stable anions. Ionization potentials and O-H bond dissociation energies computed for the most stable conformers of cation, quinonoidal, and anion forms are consistent with an important antioxidant activity.
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Affiliation(s)
- Laura Estévez
- Departamento de Química Física, Facultade de Química, Universidade de Vigo, Lagoas-Marcosende s/n 36310-Vigo Galicia, Spain
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Kozlowski D, Marsal P, Steel M, Mokrini R, Duroux JL, Lazzaroni R, Trouillas P. Theoretical Investigation of the Formation of a New Series of Antioxidant Depsides from the Radiolysis of Flavonoid Compounds. Radiat Res 2007; 168:243-52. [PMID: 17638407 DOI: 10.1667/rr0824.1] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Accepted: 02/12/2007] [Indexed: 11/03/2022]
Abstract
This paper deals with the formation of a series of antioxidant depsides obtained from flavonoid solutions irradiated with gamma rays. These reactions take place in radiolyzed alcohol solutions, a medium that is very rich in many different highly reactive species and that hosts specific reactions. We focus on the first step of those reactions, i.e., reactivity of the solute (flavonoid) with the alkoxy radicals CH(3)O(*) and CH(3)CH(2)O(*) formed in methanol and ethanol, respectively, and their carbon-centered isomers: the 1-hydroxy-methyl ((*)CH(2)OH) and the 1-hydroxy-ethyl (CH(3)(*)CHOH) radicals. Among the different flavonoid groups of molecules, only flavonols are transformed. To establish the structure-reactivity relationship that explains why the radiolytic transformation occurs only for those compounds, the process is rationalized theoretically, with Density Functional Theory calculations, taking into account the solvent effects by a Polarizable Continuum Model and a microhydrated environment (one or two water molecules surrounding the active center). The first redox reaction, occurring between the flavonol and the reactive species formed upon irradiation of the solvent, is studied in terms of (1) the O-H bond dissociation enthalpy of each OH group of the flavonoids and (2) electron abstraction from the molecule. We conclude that the reaction, initiated preferentially by the alkoxy radicals, first occurs at the 3-OH group of the flavonol. It is then followed by the formation of a peroxyl radical (after molecular oxygen or superoxide addition). The different cascades of reactions, which lead to the formation of depsides via C-ring opening, are discussed on the basis of the corresponding calculated energetic schemes.
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Affiliation(s)
- David Kozlowski
- EA 4021 Biomolécules et thérapies anti-tumorales, Université de Limoges, France
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85
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Fiorucci S, Golebiowski J, Cabrol-Bass D, Antonczak S. DFT study of quercetin activated forms involved in antiradical, antioxidant, and prooxidant biological processes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:903-11. [PMID: 17263492 DOI: 10.1021/jf061864s] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Quercetin, one of the most representative flavonoid compounds, is involved in antiradical, antioxidant, and prooxidant biological processes. Despite a constant increase of knowledge on both positive and negative activities of quercetin, it is unclear which activated form (quinone, semiquinone, or deprotonated) actually plays a role in each of these processes. Structural, electronic, and energetic characteristics of quercetin, as well as the influence of a copper ion on all of these parameters, are studied by means of quantum chemical electronic structure calculations. Introduction of thermodynamic cycles together with the role of coreactive compounds, such as reactive oxygen species, gives a glimpse of the most probable reaction schemes. Such a theoretical approach provides another hint to clarify which reaction is likely to occur within the broad range of quercetin biological activities.
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Affiliation(s)
- Sébastien Fiorucci
- Laboratoire de Chimie des Molécules Bioactives et des Arômes, UMR-CNRS 6001, Faculté des Sciences,Université de Nice-Sophia Antipolis, 06108 Nice Cedex 2, France
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86
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Kozlowski D, Trouillas P, Calliste C, Marsal P, Lazzaroni R, Duroux JL. Density Functional Theory Study of the Conformational, Electronic, and Antioxidant Properties of Natural Chalcones. J Phys Chem A 2007; 111:1138-45. [PMID: 17253666 DOI: 10.1021/jp066496+] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chalcones are natural compounds that are largely distributed in plants, fruits, and vegetables. They belong to the flavonoid group of molecules, and some of them exhibit numerous biological activities. The results of quantum chemical calculations (based on density functional theory, using the B3P86 exchange-correlation potential) are reported for 11 chalcones, in the gas phase and in the presence of an implicit solvent (using the conductor-like polarizable continuum model, C-PCM). These results are discussed in regard to the capacity of these chalcones to scavenge the 2,2-diphenyl-1-pycril-hydrazyl (DPPH) free radical. The O-H bond dissociation enthalpy (BDE) parameter, which is calculated for each OH group, seems to be the best indicator of the anti-radical property of these compounds. This demonstrates the importance of the H atom transfer mechanism to explain their capacity to scavenge the free radicals. The active sites are identified as the 6'-OH group and the 3,4-dihydroxy-catechol. The alpha,beta-double bond is influential in determining the activity.
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Affiliation(s)
- David Kozlowski
- Laboratoire de Biophysique, Faculté de Pharmacie, 2 rue du Docteur Marcland, 87025 Limoges, France
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87
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Leopoldini M, Russo N, Chiodo S, Toscano M. Iron chelation by the powerful antioxidant flavonoid quercetin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:6343-51. [PMID: 16910729 DOI: 10.1021/jf060986h] [Citation(s) in RCA: 261] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Chelation of the bare and hydrated iron(II) cation by quercetin has been investigated at the DF/B3LYP level in the gas phase. Several complexed species arising from neutral and anionic forms of the ligand have been taken into account. Both 1:1 and 1:2 metal/flavonoid stoichiometries have been considered. Results indicate that among the potential sites of chelation present on quercetin, the oxygen atoms belonging to the 3-hydroxy and 4-oxo, and to the 5-hydroxy and 4-oxo groups, are the preferred ones. Time-dependent density functional theory (TDDFT) calculations, used to reproduce the electronic UV-vis spectra of isolated quercetin and its complexes with Fe2+, were also performed in methanol and dimethylsulfoxide.
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Affiliation(s)
- Monica Leopoldini
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende (CS), Italy
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88
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A DFT study of the reactivity of OH groups in quercetin and taxifolin antioxidants: The specificity of the 3-OH site. Food Chem 2006. [DOI: 10.1016/j.foodchem.2005.05.042] [Citation(s) in RCA: 262] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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89
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Chimenti F, Cottiglia F, Bonsignore L, Casu L, Casu M, Floris C, Secci D, Bolasco A, Chimenti P, Granese A, Befani O, Turini P, Alcaro S, Ortuso F, Trombetta G, Loizzo A, Guarino I. Quercetin as the active principle of Hypericum hircinum exerts a selective inhibitory activity against MAO-A: extraction, biological analysis, and computational study. JOURNAL OF NATURAL PRODUCTS 2006; 69:945-9. [PMID: 16792415 DOI: 10.1021/np060015w] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The methanol extract from Hypericum hircinum leaves exhibited in vitro inhibition of monoamine oxidases (MAO). Bioassay-guided fractionation led to the isolation of quercetin and five compounds identified for the first time from H. hircinum. Quercetin was the only compound with a selective inhibitory activity against MAO-A, with an IC50 value of 0.010 microM. To explain MAO selective inhibition at the molecular level, a computational study was carried out by conformational search and docking techniques using recently determined crystallographic models of both enzymatic isoforms. An in vivo study in mice was carried out using the forced swimming test in order to elucidate the behavioral effects of quercetin.
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Affiliation(s)
- Franco Chimenti
- Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, 00185 Rome, Italy
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90
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Dimitrić Marković JM, Baranac JM, Brdarić TP. Electronic and infrared vibrational analysis of cyanidin-quercetin copigment complex. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:673-80. [PMID: 16257774 DOI: 10.1016/j.saa.2005.02.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Revised: 02/24/2005] [Accepted: 02/25/2005] [Indexed: 05/05/2023]
Abstract
Copigment complex formation between cyanidin and quercetin, in aqueous buffered solutions, was studied by electronic absorption and infrared vibrational spectroscopies. It was found that the association of cyanidin with quercetin occurred at pH 3.0 and pH 5.0 including cyanidin flavylium ion and anhydrobase transformation forms, respectively. Obtained copigmentation constant values of K=2726.7 (pH 3.0) and K=1093.1 (pH 5.0) indicated good association ability of the investigated molecules. Infrared spectra revealed the existence of hydrogen bonds in the copigment complexes structures. The analysis of the deconvoluted infrared spectra indicated several types of hydrogen bonds, differently formed: the H--O...H bonds with the corresponding bands around 3500 cm(-1) and bonds formed via H(3)O(+), oxonium, ion of the molecules with the corresponding bands below 3000 cm(-1).
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Affiliation(s)
- Jasmina M Dimitrić Marković
- Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia and Montenegro.
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91
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Kaldas MI, Walle UK, van der Woude H, McMillan JM, Walle T. Covalent binding of the flavonoid quercetin to human serum albumin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:4194-7. [PMID: 15884859 DOI: 10.1021/jf050061m] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Quercetin is an abundant flavonoid in the human diet with numerous biological activities, which may contribute to the prevention of human disease but also may be potentially harmful. Quercetin is oxidized in cells to products capable of covalently binding to cellular proteins, a process that may be important for its biological activities. In the present study, using radiolabeled drug and quantifying the products after electrophoretic separation, proteins to which oxidized quercetin is binding irreversibly were identified. The binding of quercetin to human serum albumin (HSA) in human blood and the effect of stimulation of neutrophilic myeloperoxidase on this binding were also measured. The in vitro binding of quercetin to eight proteins in the presence of catalytic amounts of horseradish peroxidase and hydrogen peroxide was highly selective for HSA. For all proteins the binding was dramatically decreased by reduced L-glutathione. In the blood samples, the release of neutrophilic myeloperoxidase by phorbol ester caused a 3-fold increase in the binding of quercetin to HSA. This study shows that quercetin in the presence of peroxidase/hydrogen peroxide covalently links to proteins with a particularly high affinity for HSA and that this also may occur in vivo after exposure to quercetin. This provides further insights into the complex behavior of this major dietary flavonoid.
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Affiliation(s)
- Mark I Kaldas
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, South Carolina, USA
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92
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Trouillas P, Fagnère C, Lazzaroni R, Calliste C, Marfak A, Duroux JL. A theoretical study of the conformational behavior and electronic structure of taxifolin correlated with the free radical-scavenging activity. Food Chem 2004. [DOI: 10.1016/j.foodchem.2004.02.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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93
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Fiorucci S, Golebiowski J, Cabrol-Bass D, Antonczak S. Oxygenolysis of Flavonoid Compounds: DFT Description of the Mechanism for Quercetin. Chemphyschem 2004; 5:1726-33. [PMID: 15580933 DOI: 10.1002/cphc.200400186] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Flavonoids are naturally occurring phenol derivatives present in substantial amounts in a large variety of plants, fruits and vegetables daily eaten by humans. Most of these compounds exhibit several interesting biological activities, such as antiradical and antioxidant actions. Indeed, by complexation with specific enzymes, flavonoids are notably liable to metabolize molecular dioxygen. On the basis of experimental results describing oxygenolysis of the flavonoid quercetin, activated by the enzyme quercetin 2,3-dioxygenase (2,3-QD),ur attention has focused on the role of metal center in the activation of the substrate quercetin. Thus, in the present study, by means of DFT calculations at the B3LYP/ 6-31(+)G* level on model molecular systems, we describe different mechanisms for dioxygen metabolization by quercetin. Stationary points are described, and energetic and structural analyses along the reaction paths are reported. Our calculations show that the copper cation must act as an oxidant towards the substrate and that the reaction proceeds through a 1,3-cycloaddition.
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Affiliation(s)
- Sébastien Fiorucci
- Laboratoire Arômes, Synthèses, Interactions, Faculté des Sciences, Université de Nice-Sophia Antipolis, 06108 Nice 2, France
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94
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95
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Mendoza-Wilson AM, Glossman-Mitnik D. CHIH-DFT determination of the molecular structure, infrared and ultraviolet spectra of the flavonoid quercetin. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.04.054] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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96
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Leopoldini M, Marino T, Russo N, Toscano M. Antioxidant Properties of Phenolic Compounds: H-Atom versus Electron Transfer Mechanism. J Phys Chem A 2004. [DOI: 10.1021/jp037247d] [Citation(s) in RCA: 483] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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97
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Martins HFP, Leal JP, Fernandez MT, Lopes VHC, Cordeiro MNDS. Toward the prediction of the activity of antioxidants: experimental and theoretical study of the gas-phase acidities of flavonoids. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2004; 15:848-61. [PMID: 15144974 DOI: 10.1016/j.jasms.2004.02.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2003] [Revised: 02/09/2004] [Accepted: 02/29/2004] [Indexed: 05/14/2023]
Abstract
The relative gas-phase acidities were determined for eight flavonoids, applying the kinetic method, by means of electrospray-ion trap mass spectrometry. The experimental acidity order, myricetin > luteolin > quercetin > (+/-)-taxifolin > kaempferol > apigenin > (+)-catechin > (+/-)-naringenin shows good agreement with the order obtained by theoretical calculations at the B3LYP/6-311 + G(2d,2p)//HF/6-31G(d) level. Moreover, these calculations provide the gas-phase acidities of the different OH groups for each flavonoid. The calculated acidity values (Delta(ac)H), corresponding to the most favorable deprotonation, cover a narrow range, 314.8-330.1 kcal/mol, but the experimental method is sensitive enough to differentiate the acidity of the various flavonoids. For all the flavones and the flavanol, catechin, the 4'-hydroxyl group is the most favored deprotonation site whereas for the flavanones studied, taxifolin and naringenin, the most acidic site is the 7-hydroxyl group. On the other hand, the 5-hydroxyl, in flavones and naringenin, and the 3-hydroxyl, in taxifolin and catechin, are always the less acidic positions. The acidity pattern observed for this family of compounds mainly depends on the following structural features: The ortho-catechol group, the 2,3 double bond and the 4-keto group.
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Affiliation(s)
- Hugo F P Martins
- Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
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98
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Lipoxygenase inhibition by flavonoids: semiempirical study of the structure–activity relation. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2003.12.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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99
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Le Nest G, Caille O, Woudstra M, Roche S, Guerlesquin F, Lexa D. Zn–polyphenol chelation: complexes with quercetin, (+)-catechin, and derivatives: I optical and NMR studies. Inorganica Chim Acta 2004. [DOI: 10.1016/j.ica.2003.09.014] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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100
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Leopoldini M, Pitarch IP, Russo N, Toscano M. Structure, Conformation, and Electronic Properties of Apigenin, Luteolin, and Taxifolin Antioxidants. A First Principle Theoretical Study. J Phys Chem A 2003. [DOI: 10.1021/jp035901j] [Citation(s) in RCA: 233] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Monica Leopoldini
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende (CS), Italy
| | - Immaculada Prieto Pitarch
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende (CS), Italy
| | - Nino Russo
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende (CS), Italy
| | - Marirosa Toscano
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Università della Calabria, I-87030 Arcavacata di Rende (CS), Italy
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