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Somayeh Gholivand - One of the best experts on this subject based on the ideXlab platform.
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Optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
Chemistry Central journal, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p
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optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
Chemistry Central Journal, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p < 0.05) independent variable that influenced the yield of hexyl dihydrocaffeate. Graphical abstract Synthesis of different Hexyl dihydrocaffeates in ionic liquid
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Optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
BMC, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Abstract Background Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. Results This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Conclusion Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p
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Comparative study of the antioxidant activities of some lipase-catalyzed alkyl dihydrocaffeates synthesized in ionic liquid.
Food chemistry, 2016Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:The solubility limitations of phenolic Acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of Dihydrocaffeic Acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester.
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Enzymatic esterification of Dihydrocaffeic Acid and evaluation of antioxidant activities of the synthesized alkyl-esters
2016Co-Authors: Somayeh GholivandAbstract:Solubility limitations of phenolic Acids in many lipidic environments restrict their application as effective antioxidants. Enzymatic esterification of phenolic Acids in a green media such as ionic liquid improves the lipophilicity of the resultant compounds. Herein, the investigation of a biocatalysts process for the esterification of Dihydrocaffeic Acid with different ionic liquids in order to improve the conversion of the phenolic Acid in a shorter time and increase productivity of target product was carried out. To achieve the maximum conversion yield, the lipophilization of Dihydrocaffeic Acid (DHCA) by its enzymatic esterification with hexanol in the selected ionic liquid (as a model) was optimized by response surface methodology (RSM) using a five-level and four independent variables including: dosage of the enzyme (in relation to the total weight of substrates), hexanol/Dihydrocaffeic Acid mole ratio, reaction temperature and reaction time. The obtained optimal conditions were applied for the synthesis of the other n-alkyl esters with different chain lengths. Subsequently, the synthesized esters were separated from unreacted compounds and purified via a silica gel column. The purified alkyl-esters were identified by Fourier transform infrared (FTIR) and Nuclear magnetic resonance (NMR) analysis. Finally, the effects of alkyl chain length and concentration on the anti-oxidative properties of the resultant purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and also compared with butylated hydroxytoluene (BHT) as reference compound. According to the attained results, among ionic liquids tested, 1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide was the best solvent with the highest bioconversion. Furthermore, results of the optimization showed that hexyl dihydrocaffeate (HDHCA) conversion yield was significantly (p dodecyl ester > octadecyl ester > BHT while the order of BCB anti-oxidative activity was BHT > octadecyl ester > dodecyl ester > hexyl ester > methyl ester. Therefore, in the emulsion system, the hydrophobicity and solubility of the tested esters affected the antioxidant activity of esters which revealed that the antioxidant with hydrophobic character had better anti-oxidative activity in an emulsion system.
Leong Sze Wei - One of the best experts on this subject based on the ideXlab platform.
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Optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
Chemistry Central journal, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p
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optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
Chemistry Central Journal, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p < 0.05) independent variable that influenced the yield of hexyl dihydrocaffeate. Graphical abstract Synthesis of different Hexyl dihydrocaffeates in ionic liquid
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Optimization of enzymatic esterification of Dihydrocaffeic Acid with hexanol in ionic liquid using response surface methodology
BMC, 2017Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:Abstract Background Developing an efficient lipophilization reaction system for phenolic derivatives could enhance their applications in food processing. Low solubility of phenolic Acids reduces the efficiency of phenolic derivatives in most benign enzyme solvents. The conversion of phenolic Acids through esterification alters their solubility and enhances their use as food antioxidant additives as well as their application in cosmetics. Results This study has shown that lipase-catalyzed esterification of Dihydrocaffeic Acid with hexanol in ionic liquid (1-butyl-3-methylimidazoliumbis (trifluoromethylsulfonyl) imide) was the best approach for esterification reaction. In order to achieve the maximum yield, the process was optimized by response surface methodology (RSM) based on a five-level and four independent variables such as: dosage of enzyme; hexanol/Dihydrocaffeic Acid mole ratio; temperature and reaction time. The optimum esterification condition (Y = 84.4%) was predicted to be obtained at temperature of 39.4 °C, time of 77.5 h dosage of enzyme at 41.6% and hexanol/Dihydrocaffeic Acid mole ratio of 2.1. Conclusion Finally, this study has produced an efficient enzymatic esterification method for the preparation of hexyl dihydrocaffeate in vitro using a lipase in an ionic liquid system. Concentration of hexanol was the most significant (p
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Comparative study of the antioxidant activities of some lipase-catayzed alkyl dihydrocaffeates synthesized in ionic liquid
'Elsevier BV', 2017Co-Authors: Gholivand Somayeh, Lasekan Ola, Tan, Chin Ping, Abas Faridah, Leong Sze WeiAbstract:The solubility limitations of phenolic Acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of Dihydrocaffeic Acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester
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Comparative study of the antioxidant activities of some lipase-catalyzed alkyl dihydrocaffeates synthesized in ionic liquid.
Food chemistry, 2016Co-Authors: Somayeh Gholivand, Ola Lasekan, Chin Ping Tan, Faridah Abas, Leong Sze WeiAbstract:The solubility limitations of phenolic Acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of Dihydrocaffeic Acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester.
Baukje De Roos - One of the best experts on this subject based on the ideXlab platform.
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The colonic metabolites Dihydrocaffeic Acid and dihydroferulic Acid are more effective inhibitors of in vitro platelet activation than their phenolic precursors
'Royal Society of Chemistry (RSC)', 2018Co-Authors: Baeza Gema, Bachmair Eva-maria, Wood Sharon, Mateos Raquel, Bravo Laura, Baukje De RoosAbstract:Cardiovascular disease (CVD) is the major cause of morbidity and mortality worldwide. The consumption of a healthy diet rich in polyphenols has been inversely associated with the development of CVD. This study evaluated the effects of green coffee bean extract (GCBE) and yerba mate phenolic extract (YMPE), the main phenolic and methylxanthine constituents (5-caffeoylquinic Acid, 3,5-dicaffeoylquinic Acid, caffeine, and theobromine), and their main metabolites (caffeic Acid, ferulic Acid, Dihydrocaffeic Acid (DHCA) and dihydroferulic Acid (DHFA)) on platelet activation in vitro. Upon incubation with different doses (0.01-100 μg mL or μM) of each compound, adenosine 5′-diphosphate-induced P-selectin expression and fibrinogen binding were determined using whole blood flow cytometry. Platelet P-selectin expression was significantly decreased by YMPE and all phenolic and methylxanthine constituents at physiological concentrations, compared with control, whereas fibrinogen binding on platelets was significantly increased. The colonic metabolites (DHCA and DHFA) had stronger inhibitory effects on P-selectin expression than their phenolic precursors, suggesting an increase in the efficacy to modulate platelet activation with the metabolism of the phenolic compounds.This work was funded by the Spanish Ministry of Economy and Competitivity (projects AGL2010-18269 and AGL2015-69986-R). G. B. is a FPI fellow (BES-2011-047476) granted with a bursary for short stays from MINECO (EEBB-I-14-08802). The Rowett Institute receives funding from the Scottish Government Rural and Environment Science and Analytical Services (RESAS).Peer Reviewe
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The colonic metabolites Dihydrocaffeic Acid and dihydroferulic Acid are more effective inhibitors of in vitro platelet activation than their phenolic precursors
Food & function, 2017Co-Authors: Gema Baeza, Eva-maria Bachmair, Sharon Wood, Raquel Mateos, Laura Bravo, Baukje De RoosAbstract:Cardiovascular disease (CVD) is the major cause of morbidity and mortality worldwide. The consumption of a healthy diet rich in polyphenols has been inversely associated with the development of CVD. This study evaluated the effects of green coffee bean extract (GCBE) and yerba mate phenolic extract (YMPE), the main phenolic and methylxanthine constituents (5-caffeoylquinic Acid, 3,5-dicaffeoylquinic Acid, caffeine, and theobromine), and their main metabolites (caffeic Acid, ferulic Acid, Dihydrocaffeic Acid (DHCA) and dihydroferulic Acid (DHFA)) on platelet activation in vitro. Upon incubation with different doses (0.01–100 μg mL−1 or μM) of each compound, adenosine 5′-diphosphate-induced P-selectin expression and fibrinogen binding were determined using whole blood flow cytometry. Platelet P-selectin expression was significantly decreased by YMPE and all phenolic and methylxanthine constituents at physiological concentrations, compared with control, whereas fibrinogen binding on platelets was significantly increased. The colonic metabolites (DHCA and DHFA) had stronger inhibitory effects on P-selectin expression than their phenolic precursors, suggesting an increase in the efficacy to modulate platelet activation with the metabolism of the phenolic compounds.
Gary Williamson - One of the best experts on this subject based on the ideXlab platform.
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metabolite profiling of hydroxycinnamate derivatives in plasma and urine after the ingestion of coffee by humans identification of biomarkers of coffee consumption
Drug Metabolism and Disposition, 2009Co-Authors: Angelique Stalmach, Gary Williamson, William Mullen, Denis Barron, Kenichi Uchida, Takao Yokota, Christophe Cavin, Heike Steiling, Alan CrozierAbstract:Human subjects drank coffee containing 412 mol of chlorogenic Acids, and plasma and urine were collected 0 to 24 h after ingestion and were analyzed by high-performance liquid chromatographymass spectrometry. Within 1 h, some of the components in the coffee reached nanomole peak plasma concentrations (Cmax), whereas chlorogenic Acid metabolites, including caffeic Acid-3-Osulfate and ferulic Acid-4-O-sulfate and sulfates of 3- and 4-caffeoylquinic Acid lactones, had higher Cmax values. The short time to reach Cmax (Tmax) indicates absorption of these compounds in the small intestine. In contrast, dihydroferulic Acid, its 4-O-sulfate, and Dihydrocaffeic Acid-3-O-sulfate exhibited much higher Cmax values (145–385 nM) with Tmax values in excess of 4 h, indicating absorption in the large intestine and the probable involvement of catabolism by colonic bacteria. These three compounds, along with ferulic Acid-4-O-sulfate and dihydroferulic Acid-4-O-glucuronide, were also major components to be excreted in urine (8.4–37.1 mol) after coffee intake. Feruloylglycine, which is not detected in plasma, was also a major urinary component (20.7 mol excreted). Other compounds, not accumulating in plasma but excreted in smaller quantities, included the 3-O-sulfate and 3-O-glucuronide of isoferulic Acid, dihydro(iso)ferulic Acid-3-O-glucuronide, and Dihydrocaffeic Acid-3-O-glucuronide. Overall, the 119.9 mol excretion of the chlorogenic Acid metabolites corresponded to 29.1% of intake, indicating that as well as being subject to extensive metabolism, chlorogenic Acids in coffee are well absorbed. Pathways for the formation of the various metabolites within the body are proposed. Urinary Dihydrocaffeic Acid-3-O-sulfate and feruloylgly
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Metabolite profiling of hydroxycinnamate derivatives in plasma and urine after the ingestion of coffee by humans: identification of biomarkers of coffee consumption. Drug Metab Dispos 37:1749–58
2009Co-Authors: William Mullen, Gary Williamson, Denis Barron, Kenichi Uchida, Takao Yokota, Christophe Cavin, Heike Steiling, Alan CrozierAbstract:Human subjects drank coffee containing 412 mol of chlorogenic Acids, and plasma and urine were collected 0 to 24 h after ingestion and were analyzed by high-performance liquid chromatography-mass spectrometry. Within 1 h, some of the components in the coffee reached nanomole peak plasma concentrations (Cmax), whereas chlorogenic Acid metabolites, including caffeic Acid-3-O-sulfate and ferulic Acid-4-O-sulfate and sulfates of 3- and 4-caf-feoylquinic Acid lactones, had higher Cmax values. The short time to reach Cmax (Tmax) indicates absorption of these compounds in the small intestine. In contrast, dihydroferulic Acid, its 4-O-sulfate, and Dihydrocaffeic Acid-3-O-sulfate exhibited much higher Cmax values (145–385 nM) with Tmax values in excess of 4 h, indicating absorp-tion in the large intestine and the probable involvement of catab-olism by colonic bacteria. These three compounds, along with ferulic Acid-4-O-sulfate and dihydroferulic Acid-4-O-glucuronide
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Effect of Dihydrocaffeic Acid on UV irradiation of human keratinocyte HaCaT cells
Archives of Biochemistry and Biophysics, 2008Co-Authors: Laure Poquet, Michael N Clifford, Gary WilliamsonAbstract:Dihydrocaffeic Acid, a dietary constituent and a microbial metabolite of flavonoids, is an antioxidant, but few biological effects have been examined. After its production by microflora in the colon, Dihydrocaffeic Acid is absorbed and found in plasma as a combination of free and metabolized forms. Excess solar UV radiation provokes damage and initiates immune response and inflammation in skin, sometimes leading to cancer. Dihydrocaffeic Acid reduced the cytotoxicity and pro-inflammatory cytokine production (interleukin-6 and -8) in HaCaT cells, a keratinocyte model, following UV radiation. The effect of Dihydrocaffeic Acid may result from a combination of direct radical scavenging of the reactive oxygen species formed or reinforcement of the antioxidant potential of the keratinocytes, as well as a direct interference with the pathway involved in cytokine stimulation. The minimum structure required for such an effect appears to consist of a propionate side chain attached to a catechol moiety, as indicated by the efficacy of caffeic Acid, but not of the methyl and glucuronide conjugates of Dihydrocaffeic Acid. The data obtained suggest that Dihydrocaffeic Acid is a potential candidate for photo-protection by interfering with the events initiated after UV exposure in keratinocytes.
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Investigation of the metabolic fate of Dihydrocaffeic Acid.
Biochemical pharmacology, 2007Co-Authors: Laure Poquet, Michael N Clifford, Gary WilliamsonAbstract:Abstract The antioxidant Dihydrocaffeic Acid is a dietary constituent and a microbial metabolite of flavonoids. Orally administered to rats, Dihydrocaffeic Acid was very rapidly absorbed most probably by the gastric or duodenal epithelium and excreted in urine as free and conjugated forms. LC–MS 2 analysis of plasma and urine samples allowed confident identification of the Dihydrocaffeic Acid metabolites. The parent compound was glucuronidated, sulphated or methylated, on one of the hydroxyl groups present on its phenyl ring. All the Dihydrocaffeic Acid metabolites peaked in plasma within the first 30 min following ingestion, suggesting a metabolism possibly by the gastric or duodenal cells and by the liver. Using in vitro and ex vivo models of the intestinal epithelium and the liver, the identity and source of the metabolites detected in vivo were examined. The data obtained suggest that, in rats, intestinal cells are more able to glucuronidate Dihydrocaffeic Acid, whereas liver favours sulphation. Moreover, glucuronidation, sulphation and methylation seem to be regio-selective, preferably on the 3-OH of Dihydrocaffeic Acid. The methyl conjugate, dihydroferulic Acid, was shown to be oxidized into ferulic Acid by intestinal and hepatic cells, which were also able to perform the reverse reaction, the reduction of ferulic Acid into dihydroferulic Acid. As a conclusion, the main form of Dihydrocaffeic Acid circulating in plasma after its ingestion is a mixture of different primary and secondary metabolites.
Salette Reis - One of the best experts on this subject based on the ideXlab platform.
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Phenolic Acids and derivatives: studies on the relationship among structure, radical scavenging activity, and physicochemical parameters.
Journal of agricultural and food chemistry, 2000Co-Authors: Francisco Silva, Fernanda Borges, Carla P. Guimarães, José L. F. C. Lima, Carla Matos, Salette ReisAbstract:The antiradical activity of caffeic Acid (1), Dihydrocaffeic Acid (5), and their corresponding n-alkyl esters was evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) method. Dihydrocaffeic Acid (5) was the most potent compound, having an antiradical effect higher than that of (+/-)-alpha-tocopherol, whereas caffeic Acid (1) was less efficient. Esterification of the carboxyl group of Dihydrocaffeic Acid (5) had a dramatic effect on its antiradical potency, but similar effects were not observed for caffeic Acid (1) derivatives. The n-alkyl esters of both phenolic series had similar potencies, and their antiradical activities were independent of the alkyl chain length. Dose-dependent scavenger effects were found in both series. Acid-base properties of the compounds, evaluated by using potentiometry and spectrophotometry, showed that the catechol moiety had pK(a2) and pK(a3) values of 9. 24-9.02 and 11.38-10.99 in the Dihydrocaffeic series and 8.48-8.24 and 11.38-11.07 in the caffeic series, respectively. Antiradical activity and pK(a) values of the compounds were not related.