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Caffeic Acid (caffeic + acid)
Terms modified by Caffeic Acid Selected AbstractsAn Approach towards the Quantitative Structure,Activity Relationships of Caffeic Acid and its DerivativesCHEMBIOCHEM, Issue 9 2004Rajeshwar P. Verma Dr. Abstract Caffeic acid and its derivatives are already known to possess a wide range of biological activities. We have developed quantitative structure,activity relationships (QSARs) for different series of caffeic acid derivatives (including caffeic acid) in order to understand the chemical,biological interactions governing antitumor activity against six different tumor cell lines, nitric oxide production, anti-HIV and enzymatic activities, and binding affinity to the lck domain. QSAR results have shown that the different activities of caffeic acid and its derivatives are largely dependent on their hydrophobicity or molar refractivity, with a bilinear correlation being the most important. [source] Protection of Mouse Brain from Aluminum-induced Damage by Caffeic AcidCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 1 2008Jun-Qing Yang The natural product caffeic acid is a specific inhibitor of 5-lipoxygenase (5-LOX); it also possesses antioxidant and antiinflammatory properties. The current study was designed to determine whether the neuroprotective properties of caffeic acid are due to inhibition of 5-LOX. Cerebral damage was induced in mice by intracerebroventricular microinjection of aluminum (5.0 ,g aluminum in 2.0 ,L, once a day, for 5 days). Caffeic acid was administered intragastrically at 30 min prior to aluminum and repeated daily for an additional 10 days. The brain injury was determined by observation of behavioral changes in mice, as well as by measuring biochemical and pathological changes in the cerebral tissue. The levels of 5-LOX proteins and 5-LOX mRNA expression were measured in brain tissue. Aluminum impaired learning and memory in mice produced neuronal death in hippocampi, elevated brain malondialdehyde levels, increased protein expression of amyloid precursor protein (APP), amyloid beta, and 5-LOX. It also increased 5-LOX mRNA expression and decreased choline acetyl transferase (ChAT) protein expression in the brain tissue of mice. Caffeic acid prevented brain damage as well as behavioral and biochemical changes caused by aluminum overload. The results of this study suggest that overexpression of 5-LOX accompanies the cerebral injury induced by aluminum overload in mice, and that selective inhibitors of 5-LOX may have potential value in the treatment of aluminum neurotoxicity and conceivably of diseases associated with neuronal injury. [source] Effectiveness of caffeic acid as an anti-oxidant for cod liver oilINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2003Antonella De Leonardis Summary The effectiveness of caffeic acid and butylated hydroxyanisole (BHA) as anti-oxidants for cod liver oil was investigated. The phenol were added to oil in doses of 300, 600 and 800 mg kg,1 and the samples were oxidized at 100 °C in a rancimat apparatus. Caffeic acid not only improved oil stability, but also developed a further protective action which increased hydrolytic stability, inhibited diene conjugation and reduced losses of polyunsaturated fatty acid (PUFA)-n3. Caffeic acid showed a higher anti-oxidant effect than BHA. [source] Phenolic Acid Content and Composition in Leaves and Roots of Common Commercial Sweetpotato (Ipomea batatas L.) Cultivars in the United StatesJOURNAL OF FOOD SCIENCE, Issue 6 2007V.-D. Truong ABSTRACT:, Phenolic acids in commercially important sweet potato cultivars grown in the United States were analyzed using reversed-phase high-performance liquid chromatography (HPLC). Caffeic acid, chlorogenic acid, 4,5-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 3,4-di-O-caffeoylquinic acid were well separated with an isocratic elution in less than 25 min compared to about 120 min for analyzing and re-equilibrating the column with a gradient method. The isocratic elution order of these caffeoylquinic acid derivatives was confirmed by LC-MS/MS. Chlorogenic acid was the highest in root tissues, while 3,5-di-O-caffeoylquinic acid and/or 4,5-di-O-caffeoylquinic acid were predominant in the leaves. Steam cooking resulted in statistically nonsignificant increases in the concentration of total phenolics and all the individual phenolic acids identified. Sweetpotato leaves had the highest phenolic acid content followed by the peel, whole root, and flesh tissues. However, there was no significant difference in the total phenolic content and antioxidant activity between purees made from the whole and peeled sweet potatoes. [source] An Approach towards the Quantitative Structure,Activity Relationships of Caffeic Acid and its DerivativesCHEMBIOCHEM, Issue 9 2004Rajeshwar P. Verma Dr. Abstract Caffeic acid and its derivatives are already known to possess a wide range of biological activities. We have developed quantitative structure,activity relationships (QSARs) for different series of caffeic acid derivatives (including caffeic acid) in order to understand the chemical,biological interactions governing antitumor activity against six different tumor cell lines, nitric oxide production, anti-HIV and enzymatic activities, and binding affinity to the lck domain. QSAR results have shown that the different activities of caffeic acid and its derivatives are largely dependent on their hydrophobicity or molar refractivity, with a bilinear correlation being the most important. [source] Protection of Mouse Brain from Aluminum-induced Damage by Caffeic AcidCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 1 2008Jun-Qing Yang The natural product caffeic acid is a specific inhibitor of 5-lipoxygenase (5-LOX); it also possesses antioxidant and antiinflammatory properties. The current study was designed to determine whether the neuroprotective properties of caffeic acid are due to inhibition of 5-LOX. Cerebral damage was induced in mice by intracerebroventricular microinjection of aluminum (5.0 ,g aluminum in 2.0 ,L, once a day, for 5 days). Caffeic acid was administered intragastrically at 30 min prior to aluminum and repeated daily for an additional 10 days. The brain injury was determined by observation of behavioral changes in mice, as well as by measuring biochemical and pathological changes in the cerebral tissue. The levels of 5-LOX proteins and 5-LOX mRNA expression were measured in brain tissue. Aluminum impaired learning and memory in mice produced neuronal death in hippocampi, elevated brain malondialdehyde levels, increased protein expression of amyloid precursor protein (APP), amyloid beta, and 5-LOX. It also increased 5-LOX mRNA expression and decreased choline acetyl transferase (ChAT) protein expression in the brain tissue of mice. Caffeic acid prevented brain damage as well as behavioral and biochemical changes caused by aluminum overload. The results of this study suggest that overexpression of 5-LOX accompanies the cerebral injury induced by aluminum overload in mice, and that selective inhibitors of 5-LOX may have potential value in the treatment of aluminum neurotoxicity and conceivably of diseases associated with neuronal injury. [source] Inhibition of butter oxidation by some phenolicsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2007Kalliopi Soulti Abstract The ability of some phenolic compounds to inhibit butter oxidation was evaluated. Peroxide values and thiobarbituric acid reactive substances were monitored during storage of butter at 50,°C and at 110,°C. Gallic acid, caffeic acid and catechin, each at 80,mg/L, inhibited butter oxidation at 50,°C to a degree equal to that of butylated hydroxyanisole (BHA) at 200,mg/L. Gallic acid, at 80,mg/L, was more effective than BHA, at 200,mg/L, in inhibiting butter oxidation at 110,°C. Present results indicate that some phenolics, and especially gallic acid, may be taken into account as antioxidants in butter. [source] Generation, Spectroscopic Characterization by EPR, and Decay of a Pyranine-Derived RadicalHELVETICA CHIMICA ACTA, Issue 10 2007Carolina Aliaga Abstract The pyraninoxyl radical is readily formed from the MnO2 -promoted oxidation of pyranine. The free radical can be formed in high concentrations (mM), and presents a characteristic EPR spectrum that indicates a high spin-density delocalization. It is relatively stable under nitrogen (half-life ca. 50,min) but readily decays in presence of O2. In spite of its high stability, the radical readily reacts with antioxidants (phenols and ascorbic acid) with a partial recovery of the parent pyranine. High concentrations of the pyraninoxyl radical (ca. 9,,M) are present when pyranine is exposed to a free radical source (10,mM 2,2,-azobis[2-amidinopropane], 37°). The fact that these radicals readily react with antioxidants (ascorbic acid and caffeic acid) supports the proposal that protection by antioxidants of peroxyl radical-promoted pyranine bleaching is mainly due to the occurrence of a repair mechanism. [source] The chain-breaking antioxidant activity of phenolic compounds with different numbers of O-H groups as determined during the oxidation of styreneINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 2 2009Ivan Tikhonov The technique based on monitoring oxygen consumption was applied to test 18 polyphenols (PP) and model phenolics as a chain-breaking antioxidant during the oxidation of styrene initiated by 2,2,-azobis(2,4-dimethylvaleronitril) at 37°C. The chain-breaking capability of PP was characterized by two parameters: the rate constant k1 for the reaction of antioxidants with the peroxy radical produced from styrene and the stoichiometric coefficient of inhibition, f, which shows how many kinetic chains are terminated by one molecule of PP. Rate constants k1 × 105 (in M,1 s,1) were found to be 10 (catechol), 27 (pyrogallol), 34 (3,6-di-tert-Bu-catechol), 4.3 (protocatechic acid), 12 (gallic acid), 15 (caffeic acid), <0.01 (chrysin), 1.3 (kaempferol), 19 (quercetin), 5.3 (baicalein), 16 (epicatechin), 32 (epigallocatechin), 9.0 (dihydroquercetin), 3.3 (resveratrol), and 16 (nordihydroguaiaretic acid). The value of k1 increases when going from one to two and three adjacent O-H groups in a benzene ring (catechol and pyrogallol derivatives, respectively). At the same time, two O-H groups in metaposition in a A-ring of flavonoids actually do not participate in the inhibition. For the majority of PP, f is near to 2 independent of the number of OH groups. The correlation of k1 with the structure of PP and the OH bond dissociation enthalpy has been discussed. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 41: 92,100, 2009 [source] Effectiveness of caffeic acid as an anti-oxidant for cod liver oilINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2003Antonella De Leonardis Summary The effectiveness of caffeic acid and butylated hydroxyanisole (BHA) as anti-oxidants for cod liver oil was investigated. The phenol were added to oil in doses of 300, 600 and 800 mg kg,1 and the samples were oxidized at 100 °C in a rancimat apparatus. Caffeic acid not only improved oil stability, but also developed a further protective action which increased hydrolytic stability, inhibited diene conjugation and reduced losses of polyunsaturated fatty acid (PUFA)-n3. Caffeic acid showed a higher anti-oxidant effect than BHA. [source] Characterization of a new tyrosinase from Pycnoporus species with high potential for food technological applicationsJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2005S. Halaouli Abstract Aims:, Tyrosinase production by Pycnoporus cinnabarinus and Pycnoporus sanguineus was screened among 20 strains originating from various geographical areas, particularly from tropical environments. The tyrosinase from the most efficient strain was purified and characterized and tested for food additive applications. Methods and Results:, Monophenolase and diphenolase activities of tyrosinase were measured from cell lysate from the 20 Pycnoporus strains, for 8,10 days of cultivation. The strain P. sanguineus CBS 614.73 showed the highest productivity (45·4 and 163·6 U g,1 protein per day for monophenolase and diphenolase respectively). P. sanguineus CBS 614.73 tyrosinase was purified from concentrated cell lysate, anion-exchange, size-exclusion and hydroxyapatite chromatography, with a final yield of 2% and a purification factor of 35,38. The pure enzyme was a monomere with a molecular mass of 45 kDa and it showed four isoforms or isoenzymes with pI between 4·5,5. No N-glycosylation was found. The N-terminal amino acid sequence was IVTGPVGGQTEGAPAPNR. The enzyme was shown to be almost fully active in a pH range of 6,7, in a large temperature range (30,70°C), and was stable below 60°C. The main kinetic constants were determined. The tyrosinase was able to convert p -tyrosol and p -coumaric acid into hydroxytyrosol and caffeic acid, respectively, and it could also catalyse the cross-linking formation of a model protein. Conclusions:, Among the genus Pycnoporus, known for the production of laccase, the strain P. sanguineus CBS 614.73 was shown to produce one other phenoloxidase, a new monomeric tyrosinase with a specific activity of 30 and 84 U mg,1 protein for monophenolase and diphenolase respectively. Significance and Impact of the Study:, This study identified P. sanguineus CBS 614.73 as a potential producer of a tyrosinase which demonstrated effectiveness in the synthesis of antioxidant molecules and in protein cross-linking. [source] NF- ,B in liver diseases: a target for drug therapyJOURNAL OF APPLIED TOXICOLOGY, Issue 2 2009Pablo Muriel Abstract There are five nuclear factor- ,B (NF- ,B) transcription factors with important roles in innate immunity, liver inflammation, fibrosis and apoptosis prevention. Several inhibitors of NF- ,B, like caffeic acid, captopril, curcumin, pyrrolidine dithiocarbamate, resveratrol, silymarin and thalidomide, have demonstrated antinecrotic, anticholestatic, antifibrotic and anticancer activities in the liver. A link between inflammation and hepatocellular carcinoma through the NF- ,B pathway has been observed, providing ample experimental support for the tumor-promoting function of NF- ,B in various models of cancer. NF- ,B has been associated with the induction of proinflammatory gene expression and has attracted interest as a target for the treatment of inflammatory disease. However, despite much attention being focused on the deleterious effects of NF- ,B, activation of this factor during the resolution of inflammation is associated with the production of antiinflammatory molecules like interleukin (IL)-10 and the onset of apoptosis. This suggests that NF- ,B has an antiinflammatory role in vivo involving the regulation of the resolution of inflammation. Also, NF- ,B promotes liver regeneration by upregulating IL-6 and other molecules like hepatocyte growth factor. It has been postulated that the beneficial properties of NF- ,B are due to p50 homodimers, whose activation prevents cholestatic and chronic liver injury. More basic understanding on the function of the diverse NF- ,B factors is urgently needed in different physiological and pathological conditions, because depending on the subunit composition of the dimmer, the disease and the stage of the illness, inhibition of the factor may result in a beneficial or in a deleterious response. Copyright © 2008 John Wiley & Sons, Ltd. [source] Structure,hepatoprotective activity relationship of 3,4-dihydroxycinnamic acid (caffeic acid) derivativesJOURNAL OF APPLIED TOXICOLOGY, Issue 6 2001V. Pérez-Alvarez Abstract 3,4-Dihydroxycinnamic acid (caffeic acid, CAF) is a natural product containing a catechol group with an ,,,-unsaturated carboxylic acid chain that has shown hepatoprotective properties. The aim of this work was to determine the importance of the 4-hydroxy, 3-hydroxy, 3,4-dihydroxy substituents and the double bond moiety on the hepatic pharmacological effects of the molecule. We compared the ability of the caffeic, 4-hydroxycinnamic, 3-hydroxycinnamic, cinnamic and 3,4-dihydroxyhydrocinnamic (a caffeic acid analogue without the double bond) acids at a dose of 50 mg kg,1, p.o., to reduce the liver damage produced by CCl4 (4 g kg,1, p.o.) intoxication in the rat. Cinnamic acid, the non-hydroxylated analogue, only modestly protected the experimental animals challenged with CCl4, suggesting that hydroxyl groups participate in the pharmacological properties of CAF. The 3,4-dihydroxyhydrocinnamic derivative did not show any significant differences when compared with the CAF effect in this model, suggesting that the double bond does not account for the liver pharmacological properties of CAF. In contrast, the 4-hydroxy substituent seems to be very important for hepatoprotective activity because the 4-hydroxy analogue improved almost every hepatic injury marker altered by CCl4, and in a better way than CAF did. Copyright © 2001 John Wiley & Sons, Ltd. [source] Goitrogenic activity of p -coumaric acid in ratsJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 6 2003Fatima Khelifi-Touhami Abstract The effects of three natural phenolic acids (caffeic, ferulic, and p -coumaric) on the rat thyroid gland were examined in a 3-week oral-treatment study. Forty male Wistar albino rats, divided into groups of 10 rats each and fed iodine-rich diet, were administered by gastrointestinal tube saline (control), caffeic acid, ferulic acid, or p -coumaric acid at a dose level of 0.25 ,mol/kg/day for 3 weeks. The mean absolute and relative thyroid weights in caffeic, ferulic, or p -coumaric acid groups were significantly increased to 127 and 132%, 146 and 153%, or 189 and 201% compared to control value, respectively. Histological examination of the thyroids of p -coumaric acid group revealed marked hypertrophy and/or hyperplasia of the follicles. Caffeic or ferulic groups showed slight to moderate thyroid gland enlargement. Thyroid lesions in p -coumaric acid group were associated with significant increases in cellular proliferation as indicated by [3H]thymidine incorporation. In addition, the goitrogenic effect of p -coumaric acid was further confirmed by significant decreases (50%) in serum tri-iodothyronine (T3) and thyroxine (T4), and a parallel increase (90%) in serum thyroid stimulating hormone (TSH) compared to control group. These results indicate that administration of p -coumaric acid at relatively high doses induces goiter in rats. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:324,328, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10094 [source] Permeability studies of alkylamides and caffeic acid conjugates from echinacea using a Caco-2 cell monolayer modelJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 1 2004A. Matthias Summary Background:, Echinacea is composed of three major groups of compounds that are thought to be responsible for stimulation of the immune system , the caffeic acid conjugates, alkylamides and polysaccharides. This study has focussed on the former two classes, as these are the constituents found in ethanolic liquid extracts. Objective:, To investigate the absorption of these two groups of compounds using Caco-2 monolayers, which are a model of the intestinal epithelial barrier. Results:, The caffeic acid conjugates (caftaric acid, echinacoside and cichoric acid) permeated poorly through the Caco-2 monolayers although one potential metabolite, cinnamic acid, diffused readily with an apparent permeability (Papp) of 1 × 10,4 cm/s. Alkylamides were found to diffuse through Caco-2 monolayers with Papp ranging from 3 × 10,6 to 3 × 10,4 cm/s. This diversity in Papp for the different alkylamides correlates to structural variations, with saturation and N-terminal methylation contributing to decreases in Papp. The transport of the alkylamides is not affected by the presence of other constituents and the results for synthetic alkylamides were in line with those for the alkylamides in the echinacea preparation. Conclusion:, Alkylamides but not caffeic acid conjugates are likely to cross the intestinal barrier. [source] Radical Scavenging Activity and Phenolic Compounds in Persimmon (Diospyros kaki L. cv. Mopan)JOURNAL OF FOOD SCIENCE, Issue 1 2008X.N. Chen ABSTRACT:, The Mopan persimmon (Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 ,m trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly (P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations (R2= 0.993, P < 0.05, ABTS radical; R2= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated (R2= 0.831, P < 0.05, ABTS radical; R2= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato. [source] Methodology Optimization for Quantification of Total Phenolics and Individual Phenolic Acids in Sweetpotato (Ipomoea batatas L.) RootsJOURNAL OF FOOD SCIENCE, Issue 7 2007M.S. Padda ABSTRACT:, Phenolic acids are one of the several classes of naturally occurring antioxidant compounds found in sweetpotatoes. Simplified, robust, and rapid methodologies were optimized to quantify total and individual phenolic acids in sweetpotato roots. Total phenolic acid content was quantified spectrophotometrically using both Folin,Denis and Folin,Ciocalteu reagents. The Folin,Ciocalteu reagent gave an overestimation of total phenolic acids due to the absorbance of interfering compounds (that is, reducing sugars and ascorbic acid). Individual phenolic acids were quantified by high-performance liquid chromatography (HPLC) using the latest in column technology. Four reversed-phase C18 analytical columns with different properties (dimensions, particle size, particle shape, pore size, and carbon load) were compared. Three different mobile phases using isocratic conditions were also evaluated. A column (4.6 × 150 mm) packed with 5-,m spherical silica particles of pore size 110 Å combined with 14% carbon load provided the best and fast separation of individual phenolic acids (that is, chlorogenic acid, caffeic acid, and 3 isomers of dicaffeoylquinic acid) with a total analysis time of less than 7 min. Among the 3 mobile phases tested, a mobile phase consisting of 1% (v/v) formic acid aqueous solution: acetonitrile: 2-propanol, pH 2.5 (70:22:8, v/v/v) gave adequate separation. Among the solvents tested, aqueous mixtures (80:20, solvent:water) of methanol and ethanol provided higher phenolic acid extraction efficiency than the aqueous mixture of acetone. [source] Cadmium-induced astroglial death proceeds via glutathione depletionJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2006Joo-Young Im Abstract Cadmium is a heavy metal that accumulates in the body, and its accumulation in the brain damages both neurons and glial cells. In the current study, we explored the mechanism underlying cadmium toxicity in primary cortical astroglia cultures. Chronic treatment with 10 ,M cadmium was sufficient to cause 90% cell death in 18 hr. However, unlike that observed in neurons, cadmium-induced astroglial toxicity was not attenuated by the antioxidants trolox (100 ,M), caffeic acid (1 mM), and vitamin C (1 mM). In contrast, extracellular 100 ,M glutathione (GSH; ,-Glu-Cys-Gly) or 100 ,M cysteine almost completely blocked cadmium-induced astroglial death, whereas 300 ,M oxidized GSH (GSSG) or 300 ,M cystine, which do not have the free thiol group, were ineffective. In addition, cadmium toxicity was noticeably inhibited or enhanced when intracellular GSH was, respectively, increased by using the cell-permeable glutathione ethyl ester (GSH-EE) or depleted by using buthionine sulfoximine (BSO), an inhibitor of ,-glutamylcysteine synthetase. In agreement with these data, intracellular GSH levels were found to be depressed in cadmium-treated astrocytes. These results suggest that the toxic effect of cadmium on primary astroglial cells involves GSH depletion and, furthermore, that GSH administration can potentially be used to counteract cadmium-induced astroglial cell death therapeutically. © 2005 Wiley-Liss, Inc. [source] Synergistic antioxidative activities of hydroxycinnamoyl-peptidesJOURNAL OF PEPTIDE SCIENCE, Issue 10 2009Seon-Yeong Kwak Abstract Antioxidants have become an important subject of study as an active ingredient for cosmetics and preservatives for food. We synthesized antioxidative peptide conjugates of hydroxycinnamic acids (HCAs) such as ferulic acid (FA), caffeic acid (CA), and sinapic acid (SA) by SPPS method. We measured their potential antioxidant properties by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging test and lipid autoxidation inhibition test. When the antioxidative peptides, such as glutathione analogue (GS(Bzl)H) and carnosine (CAR), were conjugated to HCAs, their antioxidative activities were enhanced significantly. CA-peptides exhibited the highest free radical scavenging activity by the DPPH test, and showed good antioxidative activity in the lipid autoxidation test. FA- and SA-peptides showed excellent antioxidative activity in the lipid autoxidation test. Furthermore, we demonstrated a synergistic antioxidative activity of HCA-peptide conjugates by comparing their antioxidative activity with that of a simple mixture of HCAs and the antioxidant peptides. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. [source] Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Mateja Colaric Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source] Optimization of extraction process for phenolic acids from black cohosh (Cimicifuga racemosa) by pressurized liquid extraction,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2006Sudarsan Mukhopadhyay Abstract An investigation to optimize the extraction of phenolic acids from black cohosh using a pressurized liquid extractor system was studied with the aim of developing a generalized approach for sample preparation of phenolic compounds from plant matrices. Operating parameters such as solvent composition, solid-to-solvent ratio, temperature, particle size distribution, and number of extraction cycles were identified as main variables that influence extraction efficiency. A mixture of methanol and water (60:40 v/v) was found to be the best solvent for total phenolics (TP) and individual phenolic acids. The four phenolic acids extracted from black cohosh were identified by HPLC and LC-MS as caffeic acid, ferulic acid, sinapic acid and isoferulic acid. Over 96% of the measured phenolics were extracted in first two cycles. The extraction efficiency for black cohosh with MeOH:H2O (60:40 v/v) was found to be maximum at a solid-to-solvent ratio of 80 mg ml,1. TP content of the extract was found to increase with temperature up to 90 °C. Particle size was found to have a large impact on extraction efficiency of TP. Samples with particle size between 0.25 mm and 0.425 mm provided optimum extraction of phenolics from black cohosh. Published in 2005 for SCI by John Wiley & Sons, Ltd. [source] Phenolic compounds, lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2002Isabel Martínez-Valverde Abstract Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p -coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59,mg,kg,1 fresh weight, while naringenin levels were lower than 12.55,mg,kg,1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32,mg,kg,1 fresh weight, followed by caffeic acid, while p -coumaric and ferulic acids showed similar concentrations lower than 5,mg,kg,1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50,mg,kg,1 fresh weight), while the concentration in the other varieties was between 50 and 30,mg,kg,1, with the exception of Liso (less than 20,mg,kg,1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry [source] Antioxidative and antimutagenic activities and polyphenol content of pesticide-free and organically cultivated green vegetables using water-soluble chitosan as a soil modifier and leaf surface sprayJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2001Huifeng Ren Abstract Five green vegetables (qing-gen-cai, Chinese Cabbage, spinach, Welsh onion and green pepper) commonly used in our daily diet were analysed to determine their antioxidative and antimutagenic activities and chemical content of polyphenols. We obtained pesticide-free and organically cultivated (O) vegetables using water-soluble chitosan as a soil modifier and leaf surface spray (as an alternative natural insecticide) in order to investigate biofunctions induced or enhanced by such specialised cultivation practices. In addition, we purchased the same varieties of vegetables cultivated on an adjacent farm in the conventional manner (C) using pesticides and chemical fertilisers in order to examine the differences in biological activities and distribution of constituents responsible for such activities. The antioxidative activity shown by O vegetables was 120% times higher than that shown by C vegetables in the case of spinach and 20,50% higher in the case of Welsh onion, Chinese cabbage and qing-gen-cai. In comparison with C vegetables, the antimutagenic activity shown by O vegetables was higher against 4-nitroquinoline oxide (4NQO) in qing-gen-cai, Chinese cabbage and Welsh onion, against benzo[a]pyrene (BaP) in all five vegetables, against 2-amino-3-methylimidazo[4,5- f]quinoline (IQ) in qing-gen-cai, Chinese cabbage and green pepper and against 3-amino-1-methyl-5H -pyrido[4,3- b]indole acetate (Trp-P-2) in spinach only. Among all green vegetable juices tested for flavonoid composition, quercitrin, caffeic acid and baicalein in O vegetables were detected in concentrations 1.3,10.4 times higher than those found in C vegetables, suggesting the influence of different cultivation practices. © 2001 Society of Chemical Industry [source] The antioxidant activity and stability of the phenolic fraction of green olives and extra virgin olive oilJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2001Turkan Keceli Abstract The antioxidant activity of phenolic extracts from olives and olive oil has been assessed by scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and by studying the effects on the stability of stripped olive oil in the absence and presence of ferric chloride. The olive extracts contained a much higher concentration (1940,5800,mg,kg,1) of phenolic components than the olive oil extract (180,mg,kg,1). Some olive extracts were more effective than the olive oil extract in scavenging DPPH radicals, but the three varieties of olives examined showed relatively large differences in both polyphenol concentration and antioxidant activity of extracts. ,-Tocopherol and extracts from both olives and olive oil were effective antioxidants in stripped olive oil at 60,°C. Ferric chloride reduced the stability of stripped olive oil, but the olive extract studied was significantly more effective as an antioxidant in the presence of the metal salt than the olive oil extract or ,-tocopherol. Ferric ions catalysed the oxidation of caffeic acid, oleuropein and phenolic components of the olive and olive oil extracts in aqueous solution (pH 5.4). The olive extract oxidised more rapidly than the olive oil extract in aqueous solution. © 2001 Society of Chemical Industry [source] Anti-glycative and anti-inflammatory effects of caffeic acid and ellagic acid in kidney of diabetic miceMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 3 2010Che-yi Chao Abstract Protective effects of caffeic acid (CA) and ellagic acid (EA) in kidney of diabetic mice were examined. CA or EA at 2.5 and 5% was mixed in diet and supplied to diabetic mice for 12,wk. Results showed that the intake of CA or EA increased renal content of these compounds, alleviated body weight loss, decreased urine output, increased plasma insulin and decreased blood glucose levels at weeks 6 and 12 (p<0.05). The intake of these compounds dose dependently reduced plasma blood urea nitrogen and elevated creatinine clearance (p<0.05). CA or EA at 5% significantly decreased the levels of plasma HbA1c, urinary glycated albumin, renal carboxymethyllysine, pentosidine, sorbitol and fructose (p<0.05), and significantly diminished renal activity of aldose reductase and sorbitol dehydrogenase, as well as suppressed renal aldose reductase mRNA expression (p<0.05). CA or EA dose dependently lowered renal levels of IL-6, IL-1,, tumor necrosis factor (TNF)-, and monocyte chemoattractant protein 1 (MCP-1) (p<0.05). Furthermore, CA or EA dose dependently down-regulated tumor necrosis factor-, and monocyte chemoattractant protein-1 mRNA expression in kidney (p<0.05). Based on the observed anti-glycative and anti-inflammatory effects, the supplement of CA or EA might be helpful for the prevention or attenuation of diabetic kidney diseases. [source] Production of hydrogen peroxide is responsible for the induction of apoptosis by hydroxytyrosol on HL60 cellsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 7 2009Roberto Fabiani Abstract Hydroxytyrosol [3,4-dihydroxyphenylethanol (3,4-DHPEA)], a phenolic compound found exclusively in olive oil, exerts growth-suppressive and pro-apoptotic effects on different cancer cells. Although some molecular mechanisms involved in the pro-apoptotic activity of 3,4-DHPEA have been proposed, the initial stress signals responsible of this phenomenon are not known. Our aim was to assess the involvement of reactive oxygen species as mediators of apoptosis induced by 3,4-DHPEA on HL60 cells. Apoptosis was determined by analyzing the nuclear fragmentation by both fluorescence microscopy and flow cytometry. The externalization of phosphatidylserine was evidenced using an Annexin V-FITC kit. The concentration of H2O2 in the culture medium was measured by the ferrous ion oxidation-xylenol orange method. The pro-apoptotic effect of 3,4-DHPEA (100 ,M) was prevented by N -acetyl-cysteine, ascorbate, and ,-tocopherol. Catalase suppressed the 3,4-DHPEA-induced apoptosis, while the Fe(II)-chelating reagent o -phenantroline showed no effect, suggesting the involvement of H2O2 but not of OH,. Indeed, 3,4-DHPEA caused accumulation of H2O2 in the culture medium. Tyrosol (p -hydroxyphenylethanol) and caffeic acid, compounds structurally similar to 3,4-DHPEA but not able to generate H2O2, did not induce an appreciable apoptotic effect. This is the first study demonstrating that apoptosis induction by 3,4-DHPEA is mediated by the extracellular production of H2O2. [source] Phenolic acids in black raspberry and in the gastrointestinal tract of pigs following ingestion of black raspberryMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue S1 2009Xianli Wu Abstract Black raspberries (BRB) contain high levels of polyphenols and have been demonstrated to be chemopreventive. In order to investigate the underlying mechanism and study the metabolism of anthocyanins, pigs were fed freeze-dried BRB powder or purified diet (control) and three segments of the gastrointestinal (GI) tract (small intestine, cecum, and colon; 4 h after feeding) were collected for analysis of phenolic acids. Protocatechuic acid was the major phenolic acid (8.35 mg/100 g, dry weight (DW)) in BRB, followed by p -coumaric acid (1.63 mg/100 g, DW), caffeic acid (1.34 mg/100 g, DW), ferulic acid (0.24 mg/100 g, DW), and 3-hydroxybenzoic acid (0.20 mg/100 g, DW). Recoveries of these five phenolic acids in the whole GI tract were 199.9 ± 54.0%, 7.0 ± 3.0%, 37.0 ± 9.7%, 56.6 ± 31.3%, and 916.8 ± 642.3% (mean ± SEM, n = 5), respectively, and quantities in contents of the GI tract ranged from 0.13 ± 0.05 ,mol (p -coumaric acid) to 23.47 ± 6.09 ,mol (protocatechuic acid) (mean ± SEM, n = 5). Six other phenolic acids were detected primarily in the cecum and/or colon which were not in BRB, with total contents in the GI tract ranging from 0.18 ± 0.18 ,mol (homovanillic acid) to 8.49 ± 4.31 ,mol (homoprotocatechuic acid). Total phenolic acids in the GI tract were 49.32 ± 16.37 ,mol (mean ± SEM, n = 5). Phenolic acids measured in the GI tract accounted for only 6.31% of the degraded anthocyanins. [source] Modulation of oxidative cell damage by reconstituted mixtures of phenolic apple juice extracts in human colon cell linesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 4-5 2006Sandra Schaefer Abstract Diets rich in fruits and vegetables are associated with a lower risk of tumour induction in the intestine and other sites. Apple juice with high amounts of antioxidative phenolics might protect the intestine against reactive oxygen species-mediated cell damage. We investigated to which extent the preventive effectiveness of polyphenolic juice extracts is governed by the amounts of five major constituents (rutin, phloridzin, chlorogenic acid, caffeic acid and epicatechin). In human colon cell lines (Caco-2, HT29), reconstituted mixtures of these phenolics were investigated in comparison to the original juice extracts, originating from cider and table apples. Parameters studied were (oxidative) DNA damage (Comet assay), cellular redox status (dichlorofluorescein assay) and Trolox equivalent antioxidant capacity (TEAC). The TEAC of the reconstituted mixtures was higher compared to the respective original extracts (4.7,7.3 mM vs. 3.6,4.2 mM Trolox). After 24 h cell incubation, menadione-induced (oxidative) DNA damage was more effectively reduced by the reconstituted mixtures (1,100 ,g/mL, 24 h), as compared to the original extracts. In contrast, the cellular ROS level was reduced to a rather similar extent by original extracts and reconstituted mixtures. The results lead to the conclusion that the selected constituents in their authentic proportions substantially account for the antioxidative effectiveness of phenolic apple juice extracts. [source] Antioxidant and antiinflammatory activities of Sideritis perfoliata subsp. perfoliata (Lamiaceae)PHYTOTHERAPY RESEARCH, Issue 4 2008Maria-Thiresia Charami Abstract Sideritis perfoliata L. subsp. perfoliata is a plant widely used in folk medicine in Greece since antiquity because of its antiinflammatory, antirheumatic, antiulcer, digestive and vasoprotective properties. Phytochemical investigations of the polar extracts afforded four flavonoid glycosides, four phenylpropanoic glycosides, caffeic acid and one iridoid, ajugoside. Reactive oxygen species (ROS) are implicated in the aetiology of several inflammatory processes. In the present study polar fractions and isolated compounds from S. perfoliata subsp. perfoliata were evaluated for their antioxidant activity using DPPH spectrophotometric and TBA lipid peroxidation assays, as well as for their antiinflammatory activity using the soybean lipoxygenase bioassay. All extracts and isolated compounds showed significant antioxidant and inhibitory activity against soybean lipoxygenase. These findings give support to the ethnopharmacological use of the plant in the treatment of several inflammatory ailments. Copyright © 2008 John Wiley & Sons, Ltd. [source] Identification of caffeic acid derivatives in Actea racemosa (Cimicifuga racemosa, black cohosh) by liquid chromatography/tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 9 2003Wenkui Li Caffeic acid derivatives occurring in black cohosh [Cimicifuga racemosa (L.) Nutt., Actaea racemosa (Ranunculaceae)], some of which may have pharmacological activity, were analyzed using high-performance liquid chromatography (HPLC) electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in a complex plant matrix. Based on these studies, structurally characteristic product ions and neutral molecule losses were identified, which were then used during LC/MS/MS with product ion scanning, precursor scanning and constant neutral loss scanning to detect caffeic acid derivatives in a crude extract of black cohosh. Several caffeic acid derivatives were detected, and the identification of six of them were confirmed by comparison with authentic standards including caffeic acid, ferulic acid, isoferulic acid, fukinolic acid, cimicifugic acid A, and cimicifugic acid B. Four other compounds were detected that appeared to be caffeic acid derivatives based on LC/MS/MS retention times, molecular weights, and fragmentation patterns during MS/MS. Since standards were unavailable for these four compounds, they were tentatively identified using LC/MS/MS as cimicifugic acid E, cimicifugic acid F, dehydrocimicifugic acid A, and dehydrocimicifugic acid B. Dehydrocimicifugic acid A and dehydrocimicifugic acid B have not been reported previously to be constituents of black cohosh. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||