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Qiu C, Wang X, Zuo J, Li R, Gao C, Chen X, Liu J, Wei W, Wu J, Hu G, Song W, Xu N, Liu L. Systems engineering Escherichia coli for efficient production p-coumaric acid from glucose. Biotechnol Bioeng 2024; 121:2147-2162. [PMID: 38666765 DOI: 10.1002/bit.28721] [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: 01/30/2024] [Revised: 04/06/2024] [Accepted: 04/12/2024] [Indexed: 06/13/2024]
Abstract
P-coumaric acid (p-CA), a pant metabolite with antioxidant and anti-inflammatory activity, is extensively utilized in biomedicine, food, and cosmetics industry. In this study, a synthetic pathway (PAL) for p-CA was designed, integrating three enzymes (AtPAL2, AtC4H, AtATR2) into a higher l-phenylalanine-producing strain Escherichia coli PHE05. However, the lower soluble expression and activity of AtC4H in the PAL pathway was a bottleneck for increasing p-CA titers. To overcome this limitation, the soluble expression of AtC4H was enhanced through N-terminal modifications. And an optimal mutant, AtC4HL373T/G211H, which exhibited a 4.3-fold higher kcat/Km value compared to the wild type, was developed. In addition, metabolic engineering strategies were employed to increase the intracellular NADPH pool. Overexpression of ppnk in engineered E. coli PHCA20 led to a 13.9-folds, 1.3-folds, and 29.1% in NADPH content, the NADPH/NADP+ ratio and p-CA titer, respectively. These optimizations significantly enhance p-CA production, in a 5-L fermenter using fed-batch fermentation, the p-CA titer, yield and productivity of engineered strain E. coli PHCA20 were 3.09 g/L, 20.01 mg/g glucose, and 49.05 mg/L/h, respectively. The results presented here provide a novel way to efficiently produce the plant metabolites using an industrial strain.
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Affiliation(s)
- Chong Qiu
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Xiaoge Wang
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Jiaojiao Zuo
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China
| | - Runyang Li
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China
| | - Cong Gao
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Xiulai Chen
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Jia Liu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Wanqing Wei
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
| | - Jing Wu
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Guipeng Hu
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Wei Song
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Nan Xu
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China
| | - Liming Liu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi, China
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Da-yang TE, Fifen JJ, Conradie J, Conradie MM. Structures, temperature effect, binding and clustering energies of Cu2+(MeOH)n=1-8 clusters and extrapolations. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Reactivities of Hydroxycinnamic Acid Derivatives Involving Caffeic Acid toward Electrogenerated Superoxide in N,N-Dimethylformamide. ELECTROCHEM 2022. [DOI: 10.3390/electrochem3030024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Reactivity of (2E)-3-(3,4-dihydroxyphenyl)prop-2-enoic acid (caffeic acid), classified as a hydroxycinnamic acid (HCA) derivative, toward electrogenerated superoxide radical anion (O2•−) was investigated through cyclic voltammetry, in situ electrolytic electron spin resonance spectrometry, and in situ electrolytic ultraviolet–visible spectrometry in N,N-dimethylformamide (DMF), aided by density functional theory (DFT) calculations. The quasi-reversible redox of dioxygen/O2•− is modified in the presence of caffeic acid, suggesting that O2•− is scavenged by caffeic acid through proton-coupled electron transfer. The reactivities of caffeic acid toward O2•− are mediated by the ortho-diphenol (catechol) moiety rather than by the acryloyl group, as experimentally confirmed in comparative analyses with other HCAs. The electrochemical and DFT results in DMF suggested that a concerted two-proton-coupled electron transfer mechanism proceeds via the catechol moiety. This mechanism embodies the superior kinetics of O2•− scavenging by caffeic acid.
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Holtomo O, Rhyman L, Nsangou M, Ramasami P, Motapon O. Reaction of •OH with CHCl=CH-CHF2 and its atmospheric implication for future environmental-friendly refrigerant. PURE APPL CHEM 2021. [DOI: 10.1515/pac-2021-0116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
In order to understand the atmospheric implication of the chlorinated hydrofluoroolefin (HFO), the geometrical structures and the IR absorption cross sections of the stereoisomers 1-chloro-3,3-difluoropropene were studied using the B3LYP/6-31G(3df) and M06-2X/6-31G(3df) methods in the gas phase. The cis-trans isomerization was assessed using the M06-2X/6-311++G(3df,p)//6-31+G(3df,p) method. The latter method was also employed for thermochemistry and the rate coefficients of the reactions of •OH with the cis- and trans-isomers in the temperature ranging from 200 to 400 K. The computational method CCSD/cc-pVTZ//M06-2X/6-31+G(3df,p) was used to benchmark the rate coefficients. It turns out that, the trans-isomer is more stable than cis-isomer and the trans- to cis-isomerization is thermodynamically unfavorable. The rate coefficient follows the Gaussian law with respect to the inverse of temperature. At the global temperature of stratosphere, the calculated rate coefficients served to estimate the atmospheric lifetime along with the photochemical ozone creation potential (POCP). This yielded lifetimes of 4.31 and 7.31 days and POCPs of 3.80 and 2.23 for the cis- and trans-isomer, respectively. The radiative forcing efficiencies gave 0.0082 and 0.0152 W m−2 ppb−1 for the cis- and trans-isomer, respectively. The global warming potential approached zero for both stereoisomers at 20, 100, and 500 years time horizons.
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Affiliation(s)
- Olivier Holtomo
- Department of Physics , Faculty of Science, University of Bamenda , Bambili P.O. Box 39 , Cameroon
- Department of Physics , Faculty of Science, University of Maroua , Maroua P.O. Box 814 , Cameroon
| | - Lydia Rhyman
- Department of Chemistry , Computational Chemistry Group, Faculty of Science, University of Mauritius , Réduit 80837 Mauritius
- Department of Chemical Sciences , Centre for Natural Product Research, University of Johannesburg , Doornfontein , Johannesburg 2028 , South Africa
| | - Mama Nsangou
- Department of Physics , Higher Teacher's Training College, University of Maroua , Maroua P.O. Box 46 , Cameroon
- Department of Physics , Faculty of Science, University of Ngaoundéré , Ngaoundéré P.O. Box 454 , Cameroon
| | - Ponnadurai Ramasami
- Department of Chemistry , Computational Chemistry Group, Faculty of Science, University of Mauritius , Réduit 80837 Mauritius
- Department of Chemical Sciences , Centre for Natural Product Research, University of Johannesburg , Doornfontein , Johannesburg 2028 , South Africa
| | - Ousmanou Motapon
- Department of Physics , Faculty of Science, University of Maroua , Maroua P.O. Box 814 , Cameroon
- Laboratory of Fundamental Physics, Faculty of Science, University of Douala , Douala P.O. Box 24157 , Cameroon
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Holtomo O, Mbigah MD, Nsangou M, Motapon O. Insight of UV-vis spectra and atmospheric implication for the reaction of ˙OH radical towards glyphosate herbicide and its hydrates. RSC Adv 2021; 11:16404-16418. [PMID: 35479155 PMCID: PMC9030808 DOI: 10.1039/d1ra01591e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/20/2021] [Indexed: 11/28/2022] Open
Abstract
The rate constant of the reactions of ˙OH radicals with glyphosate (GPS) and its hydrates (GPS(H2O)n=1–3) were evaluated using the dual method M06-2X/6-311++G(df,p)//6-31+G(df,p) over the temperature range of 200–400 K. The results served to estimate the atmospheric lifetime along with the photochemical ozone creation potential (POCP). The calculations yielded an atmospheric lifetime of 2.34 hours and a POCP of 24.7 for GPS. Upon addition of water molecules, there is an increase of lifetime and decrease of POCP for water monomer and water dimer. The POCP for water trimer is slightly above the gaseous GPS. However, the POCPs of GPS and its hydrates are comparable to that of alkanes. The GPS and its hydrates were found to be a potential reservoir of CO2. The acidification potential (AP) of GPS was found to be 0.189 and decreases upon addition of water molecules. This shows negligible contribution to rain acidification as the AP is less than that of SO2. The UV-vis spectra were attained using the M06-L/6-311++G(3df,3pd) method and cover the range 160–260 nm which fits well with experiment. The rate constant of the reactions of ˙OH radical with glyphosate (GPS) and its hydrates (GPS(H2O)n=1–3) were evaluated using the dual method M06-2X/6-311++G(df,p)//6-31+G(df,p) over the temperature range of 200–400 K.![]()
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Affiliation(s)
- Olivier Holtomo
- Department of Physics
- Faculty of Science
- University of Bamenda
- Cameroon
- Department of Physics
| | | | - Mama Nsangou
- Department of Physics
- Higher Teacher's Training College
- University of Maroua
- Cameroon
- Department of Physics
| | - Ousmanou Motapon
- Department of Physics
- Faculty of Science
- University of Maroua
- Cameroon
- Laboratory of Fundamental Physics
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Tabrizi L, Nguyen TLA, Tran HDT, Pham MQ, Dao DQ. Antioxidant and Anticancer Properties of Functionalized Ferrocene with Hydroxycinnamate Derivatives-An Integrated Experimental and Theoretical Study. J Chem Inf Model 2020; 60:6185-6203. [PMID: 33233887 DOI: 10.1021/acs.jcim.0c00730] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Two ferrocenyl derivatives, Fc-CA and Fc-FA, were synthesized by a condensation reaction between the amino ferrocene and hydroxycinnamic acids, that is, caffeic acid (CA) and ferulic acid (FA). The structures and purity of all compounds were characterized by 1H- and 13C NMR spectroscopies, Mass spectrometry (MS), and elemental analysis. The antioxidant properties of Fc-CA and Fc-FA and of its ligand were studied for free radical scavenging activity toward DPPH•, superoxide anion (O2•-), NO•, and ABTS•+ by UV-vis and electron spin resonance spectroscopies. The cytotoxicity of Fc-CA and Fc-FA against MCF-7 and MDA-MB-231 breast cancer cells and MRC-5 human lung fibroblasts cell was higher than that of cisplatin. The geometry and electronic structures of all compounds were then simulated using density functional theory at M05-2X/6-311+G(d,p) level of theory. Thermodynamics of the free radical quenching reactions by common mechanisms reveal the higher antioxidant properties of the Fc-CA and Fc-FA in comparison to their ligands. An in-depth study of the free radical scavenging activity against HOO• and HO• radicals was performed for two of the most favorable and competitive mechanisms, the hydrogen transfer (either hydrogen atom transfer or proton-coupled electron transfer mechanisms) and the radical adduct formation. The in silico studies indicated that ferrocenyl derivatives exhibited prominent binding affinity to protein models in comparison to CA and FA. Their dock scores were notable at ligand binding sites of ERα, Erβ, and JAK2 proteins. Dock pose analysis also shed light into the possible mechanism of action for the studied compounds.
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Affiliation(s)
- Leila Tabrizi
- School of Chemistry, National University of Ireland, Galway, University Road, Galway H91 TK33, Ireland
| | - Thi Le Anh Nguyen
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.,Faculty of Natural Sciences, Duy Tan University, Da Nang 550000, Vietnam
| | | | - Minh Quan Pham
- Institute of Natural Products Chemistry, Vietnam Academy of Science and Technology, Hanoi 100000, Vietnam.,Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi 100000, Vietnam
| | - Duy Quang Dao
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam
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Structure, antioxidative potency and potential scavenging of OH and OOH of phenylethyl-3,4-dihydroxyhydrocinnamate in protic and aprotic media: DFT study. J Mol Graph Model 2017; 78:221-233. [DOI: 10.1016/j.jmgm.2017.10.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/09/2017] [Accepted: 10/16/2017] [Indexed: 02/06/2023]
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8
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A DFT Study of Structural and Bonding Properties of Complexes Obtained from First-Row Transition Metal Chelation by 3-Alkyl-4-phenylacetylamino-4,5-dihydro-1H-1,2,4-triazol-5-one and Its Derivatives. Bioinorg Chem Appl 2017; 2017:5237865. [PMID: 28757814 PMCID: PMC5512031 DOI: 10.1155/2017/5237865] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 05/03/2017] [Indexed: 11/18/2022] Open
Abstract
Density functional calculations were used to explore the complexation of 3-alkyl-4-phenylacetylamino-4,5-dihydro-1h-1,2,4-triazol-5-one (ADPHT) derivatives by first-row transition metal cations. Neutral ADPHT ligand and mono deprotonated ligands have been used. Geometry optimizations have been performed in gas-phase and solution-phase (water, benzene, and N,N-dimethylformamide (DMF)) with B3LYP/Mixed I (LanL2DZ for metal atom and 6-31+G(d,p) for C, N, O, and H atoms) and with B3LYP/Mixed II (6-31G(d) for metal atom and 6-31+G(d,p) for C, N, O, and H atoms) especially in the gas-phase. Single points have also been carried out at CCSD(T) level. The B3LYP/Mixed I method was used to calculate thermodynamic energies (energies, enthalpies, and Gibb energies) of the formation of the complexes analyzed. The B3LYP/Mixed I complexation energies in the gas phase are therefore compared to those obtained using B3LYP/Mixed II and CCSD(T) calculations. Our results pointed out that the deprotonation of the ligand increases the binding affinity independently of the metal cation used. The topological parameters yielded from Quantum Theory of Atom in Molecules (QTAIM) indicate that metal-ligand bonds are partly covalent. The significant reduction of the proton affinity (PA) observed when passing from ligands to complexes in gas-phase confirms the notable enhancement of antioxidant activities of neutral ligands.
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9
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Concerted two-proton–coupled electron transfer from catechols to superoxide via hydrogen bonds. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.05.034] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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10
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Antioxidative Potency and UV–Vis spectra features of the compounds resulting from the chelation of Fe2+ by Caffeic Acid Phenethyl Ester and two of its derivatives. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.06.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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11
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Holtomo O, Nsangou M, Fifen JJ, Motapon O. DFT study of the effect of solvent on the H-atom transfer involved in the scavenging of the free radicals (·)HO2 and (·)O2(-) by caffeic acid phenethyl ester and some of its derivatives. J Mol Model 2014; 20:2509. [PMID: 25388279 DOI: 10.1007/s00894-014-2509-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 10/20/2014] [Indexed: 11/26/2022]
Abstract
H-atom transfer from caffeic acid phenethyl ester (CAPE), MBC (3-methyl-2-butenyl caffeate), BC (benzoic caffeate), P3HC (phenethyl-3-hydroxycinnamate), and P4HC (phenethyl-4-hydroxycinnamate) to the selected free radicals (·)HO2 and (·)O2(-) was studied. Such a transfer can proceed in three different ways: concerted proton-coupled electron transfer (CPCET), electron transfer followed by proton transfer (ET-PT), and proton transfer followed by electron transfer (PT-ET). The latter pathway is sometimes competitive with SPLET (sequential proton loss electron transfer) in polar media. Analyzing the thermodynamic descriptors of the reactions of CAPE and its derivatives with co-reactive species-in particular, the free energies of reactions, the activation barrier to the CPCET mechanism, and their rate constants-appears to be the most realistic method of investigating the H-atom transfers of interest. These analyses were performed via DFT calculations, which agree well with the data acquired from experimental studies (IC50) and from CBS calculations. The CPCM solvation model was used throughout the work, while the SMD model-employed as a reference-was used only for CAPE. The main conclusion drawn from the analysis was that SPLET is the mechanism that governs the reaction of phenolic acids with (·)HO2, while PT-ET governs the reaction of phenols with (·)O2(-). In kinetic investigations of the CPCET process, the rate constant decreases as the solvent polarity increases, so the reaction velocity slows down.
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Affiliation(s)
- Olivier Holtomo
- Laboratory of Fundamental Physics, Faculty of Science, University of Douala, Douala, P. O. Box 24157, Cameroon
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Mura F, Silva T, Castro C, Borges F, Zuñiga MC, Morales J, Olea-Azar C. New insights into the antioxidant activity of hydroxycinnamic and hydroxybenzoic systems: spectroscopic, electrochemistry, and cellular studies. Free Radic Res 2014; 48:1473-84. [PMID: 25236566 DOI: 10.3109/10715762.2014.965702] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A series hydroxycinnamic and gallic acids and their derivatives were studied with the aim of evaluating their in vitro antioxidant properties both in homogeneous and in cellular systems. It was concluded from the oxygen radical absorbance capacity-fluorescein (ORAC-FL), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and cyclic voltammetry data that some compounds exhibit remarkable antioxidant properties. In general, in homogeneous media (DPPH assay), galloyl-based cinnamic and benzoic systems (compounds 7-11) were the most active, exhibiting the lowest oxidation potentials in both dimethyl sulfoxide (DMSO) and phosphate buffer. Yet, p-coumaric acid and its derivatives (compounds 1-3) disclosed the highest scavenging activity toward peroxyl radicals (ORAC-FL assay). Interesting structure-property- activity relationships between ORAC-FL, or DPPH radical, and redox potentials have been attained, showing that the latter parameter can be a valuable antioxidant measure. It was evidenced that redox potentials are related to the structural features of cinnamic and benzoic systems and that their activities are also dependent on the radical generated in the assay. Electron spin resonance data of the phenoxyl radicals generated both in DMSO and phosphate buffer support the assumption that radical stability is related to the type of phenolic system. Galloyl-based cinnamic and benzoic ester-type systems (compounds 9 and 11) were the most active and effective compounds in cell-based assays (51.13 ± 1.27% and 54.90 ± 3.65%, respectively). In cellular systems, hydroxycinnamic and hydroxybenzoic systems operate based on their intrinsic antioxidant outline and lipophilic properties, so the balance between these two properties is considered of the utmost importance to ensure their performance in the prevention or minimization of the effects due to free radical overproduction.
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Affiliation(s)
- F Mura
- Department of Inorganic and Analytical Chemistry, Laboratory of Free Radicals and Antioxidants, Faculty of Chemical and Pharmaceutical Sciences, University of Chile , Santiago de Chile , Chile
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Senthil kumar K, Kumaresan R. A comparative study on the antioxidant properties of bractein and cernuoside by the DFT method. MONATSHEFTE FUR CHEMIE 2013. [DOI: 10.1007/s00706-013-1024-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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León-Carmona JR, Alvarez-Idaboy JR, Galano A. On the peroxyl scavenging activity of hydroxycinnamic acid derivatives: mechanisms, kinetics, and importance of the acid-base equilibrium. Phys Chem Chem Phys 2012; 14:12534-43. [PMID: 22511179 DOI: 10.1039/c2cp40651a] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The peroxyl radical scavenging activity of four hydroxycinnamic acid derivatives (HCAD) has been studied in non-polar and aqueous solutions, using the density functional theory. The studied HCAD are: ferulic acid (4-hydroxy-3-methoxycinnamic acid), p-coumaric acid (trans-4-hydroxycinnamic acid), caffeic acid (3,4-dihydroxycinnamic acid), and dihydrocaffeic acid (3-(3,4-dihydroxyphenyl)-2-propionic acid). It was found that the polarity of the environment plays an important role in the relative efficiency of these compounds as peroxyl scavengers. It was also found that in aqueous solution the pH is a key factor for the overall reactivity of HCAD towards peroxyl radicals, for their relative antioxidant capacity, and for the relative importance of the different mechanisms of reaction. The H transfer from the phenolic OH has been identified as the main mechanism of reaction in non-polar media and in aqueous solution at acid pHs. On the other hand, the single electron transfer mechanism from the phenoxide anion is proposed to be the one contributing the most to the overall peroxyl scavenging activity of HCAD in aqueous solution at physiological pH (7.4). This process is also predicted to be a key factor in the reactivity of these compounds towards a large variety of free radicals.
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Affiliation(s)
- Jorge Rafael León-Carmona
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, San Rafael Atlixco 186, Col, Vicentina, Iztapalapa, C. P. 09340, México DF, México
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Fifen J, Nsangou M, Dhaouadi Z, Motapon O, Jaidane N. Solvent effects on the antioxidant activity of 3,4-dihydroxyphenylpyruvic acid : DFT and TD-DFT studies. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.03.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Dhaouadi Z, Nsangou M, Garrab N, Anouar E, Marakchi K, Lahmar S. DFT study of the reaction of quercetin with and radicals. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.theochem.2009.02.034] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Fifen J, Nsangou M, Dhaouadi Z, Motapon O, Lahmar S. Single or double hydrogen atom transfer in the reaction of metal – Associated phenolic acids with •OH radical: DFT study. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.theochem.2008.12.046] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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