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Hélène Fulcrand - One of the best experts on this subject based on the ideXlab platform.
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid.
Journal of agricultural and food chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV−visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2−4.0), due to the low pKa and high pKh values, the et...
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV-visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2-4.0), due to the low pKa and high pKh values, the ethyl-linked pigments are present as colored forms (flavylium cation and quinonoid bases).
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Structure of a new dimeric acetaldehyde Malvidin 3-glucoside condensation product
Tetrahedron Letters, 2002Co-Authors: Vessela Atanasova, Veronique Cheynier, Hélène Fulcrand, Christine Le Guernevé, Michel MoutounetAbstract:A new pigment was detected in wine-like model solution containing Malvidin 3-O-glucoside and acetaldehyde. This compound was isolated, and its structure was investigated by UV, MS and NMR spectroscopies. The analytical data allowed identification of it to 8,8 methyl methine-linked Malvidin 3-O-glucoside dimer. The occurrence of this pigment was demonstrated in red wine. A polymeric fraction was also isolated from the model solution and analysed by LC/MS. Detection of methyl methine-linked Malvidin 3-O-glucoside oligomers proved that acetaldehyde mediated self-condensation of anthocyanins is possible, and that the C6 position of anthocyanins seems reactive as the C8 although to a lesser extent.
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mechanisms of anthocyanin degradation in grape must like model solutions
Journal of the Science of Food and Agriculture, 1995Co-Authors: Pascale Sarni, Hélène Fulcrand, Veronique Souillol, Jeanmarc Souquet, Veronique CheynierAbstract:Oxidative degradation of o-diphenolic (eg cyanidin-3-glucoside) and non-o-diphenolic (eg Malvidin-3-glucoside) anthocyanins in the presence of caffeoyltartaric acid and grape polyphenoloxidase was studied in model solutions. Both anthocyanins reacted with the enzymically generated caffeoyltartaric acid o-quinone. Kinetic studies indicated that cyanidin-3-glucoside was degraded mostly by coupled oxidation whereas Malvidin-3-glucoside formed adducts with caffeoyltartaric acid quinone. In solutions containing equimolar amounts of the anthocyanins, both reactions took place but coupled oxidation of cyanidin-3-glucoside occurred at a faster rate, partly protecting Malvidin-3-glucoside. The occurrence of coupled oxidation resulted in sparing of caffeoyltartaric acid. Several oxidation products, including red pigments, were detected by HPLC. The UV-Vis spectra of the coloured condensation products suggested that they contained both caffeoyltartaric acid and anthocyanin moieties. All these pigments were gradually degraded to colourless compounds either by enzymatic oxidation or by further reaction with quinones.
Veronique Cheynier - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive investigation of guaiacyl-pyranoanthocyanin synthesis by one-/two-dimensional NMR and UPLC–DAD–ESI–MSn
Food Chemistry, 2016Co-Authors: Anna Vallverdú-queralt, Veronique Cheynier, Olivier Dangles, Emmanuelle Meudec, Nayla Ferreira-lima, Nicolas Sommerer, Christine Le GuernevéAbstract:In red and rose wines, the grape anthocyanins are progressively converted to more stable pigments, including phenylpyranoanthocyanins. One-/two-dimensional NMR and UPLC-DAD-ESI-MSn measurements were used to monitor the synthesis of guaiacylpyranoMalvidin 3-O-glucoside from Malvidin 3-O-glucoside and vinylguaiacol in model solutions and identify the products formed during the reaction. The highest conversion rates (30%, determined by H-1 qNMR) were obtained with a small excess of vinylguaiacol in methanol/water (70/30) at pH 3 and 35 degrees C. Two reaction pathways competed with the formation of guaiacylpyranoMalvidin 3-O-glucoside. The first one only concerns Malvidin 3-O-glucoside and consists in C-ring cleavage with formation of malvone and smaller molecular weight breakdown products. This pathway is favored at higher pH and incubation temperature. At lower pH values or in the presence of large vinylguaiacol excess, faster consumption of Malvidin 3-O-glucoside resulted from the formation of more complex pyranoanthocyanins substituted by vinylguaiacol oligomers.
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid.
Journal of agricultural and food chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV−visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2−4.0), due to the low pKa and high pKh values, the et...
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV-visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2-4.0), due to the low pKa and high pKh values, the ethyl-linked pigments are present as colored forms (flavylium cation and quinonoid bases).
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Structure determination and color properties of a new directly linked flavanol-anthocyanin dimer
Tetrahedron Letters, 2004Co-Authors: Celine Poncet-legrand, Erika Salas, Christine Le Guernevé, Helene Fulcrand-hoh, Veronique CheynierAbstract:The structure of catechin-(4alpha-->8)-Malvidin 3-O-glucoside obtained by reaction of taxifolin and Malvidin 3-O-glucoside following a protocol adapted from proanthocyanidin dimer synthesis was determined by NMR spectrometry. Incorporation of the anthocyanin moiety into a covalent linked flavanol-anthocyanin dimer did not modify its colour properties (i.e., hydration equilibrium constant and copigmentation).
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Structure of a new dimeric acetaldehyde Malvidin 3-glucoside condensation product
Tetrahedron Letters, 2002Co-Authors: Vessela Atanasova, Veronique Cheynier, Hélène Fulcrand, Christine Le Guernevé, Michel MoutounetAbstract:A new pigment was detected in wine-like model solution containing Malvidin 3-O-glucoside and acetaldehyde. This compound was isolated, and its structure was investigated by UV, MS and NMR spectroscopies. The analytical data allowed identification of it to 8,8 methyl methine-linked Malvidin 3-O-glucoside dimer. The occurrence of this pigment was demonstrated in red wine. A polymeric fraction was also isolated from the model solution and analysed by LC/MS. Detection of methyl methine-linked Malvidin 3-O-glucoside oligomers proved that acetaldehyde mediated self-condensation of anthocyanins is possible, and that the C6 position of anthocyanins seems reactive as the C8 although to a lesser extent.
Martin Pour Nikfardjam - One of the best experts on this subject based on the ideXlab platform.
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Effect of molecular environment on the formation kinetics of complexes of Malvidin-3-O-glucoside with caffeic acid and catechin.
The journal of physical chemistry. B, 2009Co-Authors: Sándor Kunsági-máté, Ashok Kumar, Pratibha Sharma, László Kollár, Martin Pour NikfardjamAbstract:The formation kinetics of Malvidin−polyphenol copigmentation complexes was studied in water−ethanol mixtures by time-dependent recording of the photoluminescence (PL) signal of Malvidin. Two reaction channels were examined according to the order of complex formation. Both channels end with the same Malvidin−polyphenol complexes formed in binary mixtures of water−ethanol. However, in the first case, the Malvidin−polyphenol complexes are formed in water first, and then their solvation shells are altered according to the changed composition of the bulk solutions after the aqueous solution is diluted with ethanol. In the second case, the stock solutions are prepared as binary solvent mixtures; therefore, the bicomponent solvation shells of the interacted species are formed prior to molecular association. Our results show a faster formation of the complexes in the former case. Evaluation of the Arrhenius parameters of the reaction shows that the activation energy of the first reaction channel is lower and the ...
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effect of ferrous and ferric ions on copigmentation in model solutions
Journal of Molecular Structure, 2008Co-Authors: Sandor Kunsagimate, László Kollár, Erika Ortmann, Kornelia Szabo, Martin Pour NikfardjamAbstract:Abstract The thermodynamics of the molecular association process between Malvidin-3-O-glucoside and ellagic acid (so-called “copigmentation”) was studied in model wine solutions in the presence and absence, respectively, of ferrous and ferric ions. The Gibbs free energy, enthalpy, and entropy values of the complexation process were determined by means of a spectrofluorometric method. A combination of the Job’s method with the van’t Hoff theory was used for data evaluation. The results show the generally exothermic character of the process. The free enthalpy changes obtained during formation of Malvidin-3-O-glucoside–ellagic acid complexes increase from −17.8 kJ/mol to −40.5 kJ/mol in the presence of Fe(II) ions. The increased free enthalpy is a consequence of the drastic reduction of entropy change due to the slight “swinging” movement of the interacting Malvidin and ellagic acid molecules in the complexes stabilized by the ferrous ions. These results are also supported by the findings of other authors stating that iron ions play an important role in the stabilization of color in the plant kingdom and various plant products.
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Entropy-driven complex formation of Malvidin-3-O-glucoside with common polyphenols in ethanol-water binary solutions.
Spectrochimica acta. Part A Molecular and biomolecular spectroscopy, 2007Co-Authors: Sándor Kunsági-máté, László Kollár, Erika Ortmann, Martin Pour NikfardjamAbstract:Abstract The complex formation of Malvidin-3- O -glucoside with several polyphenols, the so-called “copigmentation” phenomenon, was studied in aqueous solutions. To simulate the copigmentation process during fermentation, the stability of the formed complexes was examined in dependence of the ethanol content of the aqueous solution. Results indicate that stronger and larger complexes are formed, when the ethanol content exceeds a critical margin of 8 vol.% However, the size of complexes of Malvidin/procyanidin and Malvidin/epicatechin is drastically reduced above this critical concentration. Fluorescence lifetime and solvent relaxation measurements give insight into the particular processes at molecular level and will help us comprehend the first important steps during winemaking in order to recommend an optimized winemaking technology to ensure extraordinary colour stability in red wines.
Olivier Dangles - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive investigation of guaiacyl-pyranoanthocyanin synthesis by one-/two-dimensional NMR and UPLC–DAD–ESI–MSn
Food Chemistry, 2016Co-Authors: Anna Vallverdú-queralt, Veronique Cheynier, Olivier Dangles, Emmanuelle Meudec, Nayla Ferreira-lima, Nicolas Sommerer, Christine Le GuernevéAbstract:In red and rose wines, the grape anthocyanins are progressively converted to more stable pigments, including phenylpyranoanthocyanins. One-/two-dimensional NMR and UPLC-DAD-ESI-MSn measurements were used to monitor the synthesis of guaiacylpyranoMalvidin 3-O-glucoside from Malvidin 3-O-glucoside and vinylguaiacol in model solutions and identify the products formed during the reaction. The highest conversion rates (30%, determined by H-1 qNMR) were obtained with a small excess of vinylguaiacol in methanol/water (70/30) at pH 3 and 35 degrees C. Two reaction pathways competed with the formation of guaiacylpyranoMalvidin 3-O-glucoside. The first one only concerns Malvidin 3-O-glucoside and consists in C-ring cleavage with formation of malvone and smaller molecular weight breakdown products. This pathway is favored at higher pH and incubation temperature. At lower pH values or in the presence of large vinylguaiacol excess, faster consumption of Malvidin 3-O-glucoside resulted from the formation of more complex pyranoanthocyanins substituted by vinylguaiacol oligomers.
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vinylcatechin dimers are much better copigments for anthocyanins than catechin dimer procyanidin b3
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Luís Cruz, Natércia Teixeira, Nuno Mateus, Olivier Dangles, Natercia F Bras, Maria J Ramos, Victor De FreitasAbstract:The binding constants (K) for the interaction of three copigments (CP), two epimeric vinylcatechin dimers (CP1 and CP2), and catechin dimer B3 (CP3) with two pigments, Malvidin-3-glucoside (oenin) and Malvidin-3,5-diglucoside (malvin), were determined. The K values clearly show that both vinylcatechin dimers have much higher affinity for oenin and malvin than dimer B3: KCP2 > KCP1 ≫ KCP3. Quantum mechanics and molecular dynamics calculations were also performed to interpret the binding data and specify the relative arrangement of the pigment and copigment molecules within the complexes.
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid.
Journal of agricultural and food chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV−visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2−4.0), due to the low pKa and high pKh values, the et...
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UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-Malvidin 3-glucoside pigments in aqueous solution: structural transformations and molecular complexation with chlorogenic acid
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Montserrat Dueñas, Erika Salas, Veronique Cheynier, Olivier Dangles, Hélène FulcrandAbstract:The physicochemical properties of 8,8-methylmethine catechin-Malvidin 3-O-glucoside isomers, commonly referred to as catechin-ethyl-Malvidin 3-O-glucoside, have been studied in aqueous solutions and compared with those of the parent anthocyanin (Malvidin 3-O-glucoside). The hydration and acidity constants (pKh and pKa) of the catechin-ethyl-Malvidin 3-O-glucoside pigments and Malvidin 3-O-glucoside were determined by UV-visible spectroscopic measurements. The ethyl-linked catechin-Malvidin 3-O-glucoside pigments present higher stability toward hydration than the parent anthocyanin. The high resistance of these ethyl-linked pigments toward the hydration is related to the self-association that offers optimal protection from the nucleophilic attack of water. Moreover, the ethyl link may confer to the molecule enough flexibility to undergo intramolecular interaction, further protecting it from hydration and bisulfite discoloration. In the wine pH range (3.2-4.0), due to the low pKa and high pKh values, the ethyl-linked pigments are present as colored forms (flavylium cation and quinonoid bases).
Nuno Mateus - One of the best experts on this subject based on the ideXlab platform.
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enzymatic synthesis structural characterization and antioxidant capacity assessment of a new lipophilic Malvidin 3 glucoside oleic acid conjugate
Food & Function, 2016Co-Authors: Luís Cruz, Victor De Freitas, Iva Fernandes, Marta Guimarães, Nuno MateusAbstract:The chemical modification of anthocyanins (water-soluble pigments) into more lipophilic compounds is very important to expand their application in the food, medical and cosmetic industries. In this work, the synthesis of a pure Malvidin-3-glucoside–oleic acid ester derivative was achieved by enzymatic catalysis. This approach allowed us to synthesize a novel compound, Malvidin-3-O-(6′′-oleoyl)glucoside (Mv3glc–OA), which was structurally characterized by mass spectrometry and for the first time by NMR spectroscopy. The enzymatic reaction revealed to be regioselective giving only one ester product. Antioxidant features of the Malvidin-3-glucoside lipophilic derivative by means of DPPH, FRAP and lipid peroxidation assays were assessed, which confirmed that the structural modification of the genuine Malvidin-3-glucoside into a more lipophilic compound did not compromise its antioxidant potential and protected more effectively a lipidic substrate from oxidation, which is an important insight for future technological applications.
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Enzymatic synthesis, structural characterization and antioxidant capacity assessment of a new lipophilic Malvidin-3-glucoside–oleic acid conjugate
Food & function, 2016Co-Authors: Luís Cruz, Victor De Freitas, Iva Fernandes, Marta Guimarães, Nuno MateusAbstract:The chemical modification of anthocyanins (water-soluble pigments) into more lipophilic compounds is very important to expand their application in the food, medical and cosmetic industries. In this work, the synthesis of a pure Malvidin-3-glucoside–oleic acid ester derivative was achieved by enzymatic catalysis. This approach allowed us to synthesize a novel compound, Malvidin-3-O-(6′′-oleoyl)glucoside (Mv3glc–OA), which was structurally characterized by mass spectrometry and for the first time by NMR spectroscopy. The enzymatic reaction revealed to be regioselective giving only one ester product. Antioxidant features of the Malvidin-3-glucoside lipophilic derivative by means of DPPH, FRAP and lipid peroxidation assays were assessed, which confirmed that the structural modification of the genuine Malvidin-3-glucoside into a more lipophilic compound did not compromise its antioxidant potential and protected more effectively a lipidic substrate from oxidation, which is an important insight for future technological applications.
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Effect of sugar acylation on the antioxidant properties of Vitis vinifera red grape Malvidin-3-glucoside
International Journal of Food Science & Technology, 2011Co-Authors: Joana Azevedo, Natércia Teixeira, Joana Oliveira, Victor De Freitas, Nuno MateusAbstract:Summary This work aims at studying the influence of sugar acylation on the antioxidant properties of Vitis vinifera red grape Malvidin-3-glucoside. The antioxidant properties of Malvidin-3-glucoside, Malvidin-3-acetylglucoside, Malvidin-3-coumaroylglucoside and Malvidin-3-caffeoylglucoside were measured using different techniques. Their antiradical and reducing properties were determined using the DPPH and FRAP method, respectively. Malvidin-3-caffeoylglucoside displayed a DPPH value (20.2 μm Trolox eq.) much higher than Malvidin-3-glucoside (13.6 μm Trolox eq.), but no significant differences were observed from the FRAP assay. Furthermore, the ability of these compounds to inhibit lipid peroxidation in a liposome membrane system was examined by monitoring oxygen consumption and the formation of conjugated dienes. Both assays allowed concluding that Malvidin-3-caffeoylglucoside and Malvidin-3-coumaroylglucoside inhibit lipid peroxidation significantly more than Malvidin-3-glucoside. Altogether, the results reported herein indicate that acylation of Malvidin-3-glucoside with phenolic acids like caffeic or coumaric acids, but not acetic acid, increases their overall antioxidant properties.
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vinylcatechin dimers are much better copigments for anthocyanins than catechin dimer procyanidin b3
Journal of Agricultural and Food Chemistry, 2010Co-Authors: Luís Cruz, Natércia Teixeira, Nuno Mateus, Olivier Dangles, Natercia F Bras, Maria J Ramos, Victor De FreitasAbstract:The binding constants (K) for the interaction of three copigments (CP), two epimeric vinylcatechin dimers (CP1 and CP2), and catechin dimer B3 (CP3) with two pigments, Malvidin-3-glucoside (oenin) and Malvidin-3,5-diglucoside (malvin), were determined. The K values clearly show that both vinylcatechin dimers have much higher affinity for oenin and malvin than dimer B3: KCP2 > KCP1 ≫ KCP3. Quantum mechanics and molecular dynamics calculations were also performed to interpret the binding data and specify the relative arrangement of the pigment and copigment molecules within the complexes.
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Structural characterization of new Malvidin 3-glucoside-catechin aryl/alkyl-linked pigments.
Journal of agricultural and food chemistry, 2004Co-Authors: João Pissarra, Nuno Mateus, Sandra Lourenço, Ana M. González-paramás, Celestino Santos Buelga, And Artur M. S. Silva, Victor De FreitasAbstract:The condensation reaction between Malvidin 3-glucoside and catechin mediated by isobutyraldehyde, benzaldehyde, and isovaleraldehyde was conducted in model solutions at two pH values (1.5 and 3.2). The formation of new alkyl/aryl-linked adducts corresponding to the structures Malvidin 3-glucoside-isobutylcatechin, Malvidin 3-glucoside-benzylcatechin, and Malvidin 3-glucoside-3-methylbutylcatechin was respectively observed from each aldehyde. The structural characterization of these new structures has been elucidated by 1D and 2D NMR, mass spectrometry, and UV-vis techniques. These new adducts showed the same lambda(max) in the visible region at 540 nm, which is bathochromically shifted 15 nm when compared with the original anthocyanin (lambda(max) = 525 nm).
