Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CHLOROGENIC ACID”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources
PubMed1978

Inactivity of Oxidation Products of Indole-3-acetic Acid on Ethylene Production in Mung Bean Hypocotyls.

The suggestion that indole-3-acetic acid (IAA)-stimulated ethylene production is associated with oxidative degradation of IAA and is mediated by 3-methyleneoxindole (MOI) has been tested in mung bean (Phaseolus aureus Roxb.) hypocotyl segments. While IAA actively stimulated ethylene production, MOI and indole-3-aldehyde, the major products of IAA oxidation, were inactive. Tissues treated with a mixture of intermediates of IAA oxidation, obtained from a 1-hour incubation of IAA with peroxidase, failed to stimulate ethylene production. Furthermore, chlorogenic acid and p-coumaric acid, which are known to interfere with the enzymic oxidation of IAA to MOI, had no effect on IAA-stimulated ethylene production. Other oxidation products of IAA, including oxindole-3-acetic acid, indole-3-carboxylic acid, (2-sulfoindole)-3-acetic acid, and dioxindole-3-acetic acid, were all inactive. 1-Naphthaleneacetic acid was as active as IAA in stimulating ethylene production but was decarboxylated at a much lower rate than IAA, suggesting that oxidative decarboxylation of auxins is not linked to ethylene production. These results demonstrate that IAA-stimulated ethylene production in mung bean hypocotyl tissue is not mediated by MOI or other associated oxidative products of IAA.

Journal Article↗
PubMed2005

Polypodium leucotomos extract: antioxidant activity and disposition.

The extract of the fern Polypodium leucotomos (PL, Fernblock) is an oral photoprotectant with strong antioxidative properties. Recent studies to determine its chemical composition have shown 4-hydroxycinnamic acid (p-coumaric), 3 methoxy-4-hydroxycinnamic acid (ferulic), 3,4-dihydroxycinnamic acid (caffeic), 3-methoxy-4-hydroxybenzoic acid (vanillic) and 3-caffeoilquinic acid (chlorogenic) to be among its major phenolic components. No conclusive data are available, however, on the H2O2-scavenging capacity of these compounds, or on their absorption and metabolism following their oral intake. In the present work, their antioxidative capacity was assessed by the luminol/H2O2 assay, their absorption studied using Caco-2 cells to resemble the intestinal barrier, and their metabolism investigated using cultured primary rat hepatocytes. The antioxidant capacity of PL components increased in a concentration-dependent manner, with ferulic and caffeic acids the most powerful antioxidants. The apparent permeability results correspond to a human post-oral administration absorption of 70-100% for all tested substances. Coumaric, ferulic and vanillic acids were metabolized by CYP450-dependent mono-oxygenases and partially conjugated to glucuronic acid and sulfate. These phenolic compounds may contribute to the health benefits afforded by this oral photoprotectant.

Animals↗
PubMed2001

Antiproliferative constituents in the plants 7. Leaves of Clerodendron bungei and leaves and bark of C. trichotomum.

The constituents of the leaves of Clerodendron bungei STEUD. (Verbenaceae) and leaves and bark of C. trichotomum THUNB. were investigated guided by the antiproliferative activity against three tumor cell lines (MK-1: human gastric adenocarcinoma, HeLa: human uterus carcinoma, and B16F10: murine melanoma). Two phenylethanoid glycoside caffeic acid esters, acteoside and isoacteoside, were isolated as the constituents which selectively inhibit the growth of B16F10 cells. The antiproliferative activities against B16F10 cells of acteoside (GI50: 8 microM), isoacteoside (8 microM) and their methanolysis products, methyl caffeate (26 microM), 3,4-dihydroxyphenethyl alcohol (8 microM), 3,4-dihydroxyphenethyl glucoside (10 microM), desrhamnosyl acteoside (6 microM), and desrhamnosyl isoacteoside (6 microm) suggested that the 3,4-dihydroxyphenethyl alcohol group might be more responsible for the activities of acteoside and isoacteoside than the caffeoyl group. The activities of chlorogenic acid, 3,4-dihydroxyphenylacetic acid, 3-(3,4-dihydroxyphenyl) alanine, 3,4-dihydroxy-phenethylamine hydrochloride, ferulic acid, sinapic acid, and five dihydroxybenzoic acids were also determined and compared with those of the above compounds.

Animals↗
PubMed1973

The effect of greening of sorghum leaves on the molecular weight of a complex containing 4-hydroxycinnamic Acid hydroxylase activity.

During the greening of leaves of Sorghum bicolor var. Wheatland milo, the activity of 4-hydroxycinnamic (p-coumaric) acid hydroxylase in pH 6 buffered extracts was shifted from a relatively low to a high molecular weight fraction. Differences between these forms found in etiolated and green leaves were based on differential centrifugation, ammonium sulfate precipitation, and on elution patterns from Agarose A-15m. Both molecular weight forms were precipitated by protamine sulfate at pH 6, and approximately 40 to 80% of the activity of each form was associated with a 500 to 37,000g pellet when tissues were ground at pH 8 in media of either high or low osmotic concentration. Although no fraction with hydroxylase activity was ever found without any chlorogenic acid oxidase activity, the two activities frequently varied independently, and could be partially separated from each other, using the above techniques. Comparisons were made with the very small molecular weight form of 4-hydroxycinnamic acid hydroxylase characteristic of tissues of first internodes. The significance of these results in terms of possible multienzyme complexes capable of converting phenylalanine and tyrosine to cinnamic acid derivatives is discussed.

Journal Article↗
PubMed2004

Attenuation of lipid peroxidation by antioxidants in rat-1 fibroblasts: comparison of the lipid peroxidation reporter molecules cis-parinaric acid and C11-BODIPY(581/591) in a biological setting.

Lipid peroxidation is a major factor in the pathogenesis of many disease states. To detect the initial stages of lipid peroxidation or evaluate antioxidant efficacy, cis-parinaric acid (cis-PnA) has been successfully used and thoroughly validated. However, cis-PnA is not very well suited for medium throughput screening of antioxidants in living cells. We recently introduced and validated a lipid peroxidation reporter molecule, C11-BODIPY(581/591). To further explore this probe, we evaluated the protective effect of 12 natural antioxidants in rat-1 fibroblasts subjected to 50 microM cumene-hydroperoxide using both probes. The same pecking order for the individual antioxidant efficacies was obtained: alpha-tocopherol approximately gamma-tocopherol > quercetin approximately lycopene > kaempferol > palm oil > hydroxy-tyrosol > > alpha-carotene = beta-carotene = lutein = tyrosol = chlorogenic acid. This validates the accuracy of the C11-BODIPY(581/591) method and shows that this assay is an accurate and highly flexible method for indexing lipid peroxidation or determining antioxidant efficacy in living cells in a medium throughput scenario. The antioxidant efficacy was compared with their one-electron reduction potential, hydrophobicity and Trolox C equivalent antioxidant capacity. Our results show that although these parameters are valuable for determining structure-function relationships, they have limited predictive value for antioxidant efficacy in vivo.

Animals↗
PubMed2005

Influence of washing treatment and storage atmosphere on phenylalanine ammonia-lyase activity and phenolic acid content of minimally processed carrot sticks.

The influence of washing uncut and shredded carrots (Daucus carota L. ssp. sativa var. Bangor) with chlorinated and ozonated water, respectively, as well as the storage of the produce under aerobic and anaerobic conditions, respectively, on PAL activity and synthesis of phenolic compounds have been evaluated on pilot plant scale. Inherent raw material inhomogeneity was compensated by pooling large sized samples, and frequent sampling ensured significant data. PAL activity was induced by processing and linearly increased throughout storage under aerobic conditions, whereas an anaerobic atmosphere resulted in a maximum activity peak at storage day 2-4. The accumulation of phenolic compounds showed good correlation with the kinetics of PAL activity. Although the influence of the washing treatments was weak, the use of chlorinated water for washing shredded carrots slightly delayed the onset of PAL activity. The phenolic content of the minimally processed carrots was dominated by trans and cis isomers of chlorogenic acid ( approximately 95%). Additionally, the occurrence of p-coumaroylquinic acid ( approximately 5%) and the novel finding of three dicaffeoylquinic acid isomers were reported. The synthesis of phenolic compounds was controlled, depending on storage atmosphere.

Daucus carota↗
PubMed1993

High performance liquid chromatographic determination of phenolic acids in fruits and vegetables.

A simple isocratic HPLC technique has been developed for the quantitative analysis of phenolic acids (PAs) in fruits and vegetables. Nine benzoic and cinnamic acid derivatives were separated in less than 30 min, and the resolution was all more than 1.23. The ranges of linearity for PAs standards were 0.2-100 ng, even up to 600 ng (r = 0.983-1.000) and the detection limits were 0.02-0.24 mg/kg. Samples of fresh vegetables and fruits were extracted with 80% methanol and ethyl acetate, then purified with C18 Sep-Pak cartridge and determined by HPLC. This method was applied to the determination of PAs in 7 kinds of fruits and vegetables, i.e., apple, pear, Chinese cabbage, cauliflower, turnip, soybean sprout and white grape wine. The content of the 9 PAs varied widely in the 7 kinds of foods studied. The average concentrations of chlorogenic acid in apple (100.2 mg/kg) and pear (30.8 mg/kg) were quite high, and sinapinic acid was remarkable (42.5 mg/kg) in Chinese cabbage, and protocatechuic acid had the highest concentration of all the PAs in white wine.

Chromatography, High Pressure Liquid↗
PubMed1982

Biosynthesis, deposition, and partial characterization of potato suberin phenolics.

Alkaline nitrobenzene oxidation of the polymeric materials from wound-healed potato (Solanum tuberosum L. var. White Rose) tuber tissue liberated p-hydroxybenzaldehyde, vanillin, and minor amounts of syringaldehyde as determined by gas chromatography/mass spectrometry. The aromatic aldehydes were derived only from periderm. The amounts of aromatic aldehydes liberated were used as a measure of the deposition of phenolic suberin components. Phenolic deposition began after about 2 days of wound healing; after 8 days the amounts of p-hydroxybenzaldehyde released by nitrobenzene oxidation leveled off at 5 milligrams per gram dry weight and after 12 days vanillin liberation reached a maximum at 7.5 milligrams per gram dry weight. The time course of deposition of the phenolic polymeric material is analogous to that reported for the deposition of the aliphatic components of suberin and therefore these results are consistent with the proposed structure of suberin. Experiments with radiolabeled l-phenylalanine and cinnamic acid indicated that exogenous phenylalanine was less efficient than cinnamic acid as a precursor of suberin phenolics. Nitrobenzene oxidation of radiolabeled suberin preparations gave three major labeled fractions: a diethyl ether-soluble fraction containing aromatic aldehydes ( approximately 20%), an ethyl acetate-soluble fraction containing unknown compounds ( approximately 15%), and a condensed phenolic fraction ( approximately 10%). Thin-layer and gas-liquid chromatographic analysis of the ether fraction showed that the major labeled components were vanillin and p-hydroxybenzaldehyde. The condensed tannin fraction revealed the presence of several labeled macromolecular phenolic fractions. Elution profiles of the condensed tannin fraction from tissues suberized for different periods of time were essentially identical, suggesting qualitative similarity of deposition and polymerization of suberin phenolics throughout the duration of wound healing. Chlorogenic acid accumulation in wound healing potato tuber discs was measured by high-performance liquid chromatography. The level of this compound reached 130 micrograms per disk after 11 days and did not decline even after the deposition of suberin ceased, revealing no precursor role for this acid in suberization.

Journal Article↗
PubMed2003

Tyrolobibenzyls E and F from Scorzonera humilis and distribution of caffeic acid derivatives, lignans and tyrolobibenzyls in European taxa of the subtribe Scorzonerinae (Lactuceae, Asteraceae).

A chemosystematic study of the subtribe Scorzonerinae, a subtribe of the Lactuceae tribe of the Asteraceae family was performed, using the recently discovered tyrolobibenzyls as well as lignans and caffeic acid derivatives as diagnostic characters. In addition to the known compounds two new tyrolobibenzyls (E and F) were isolated and their structures were established by mass spectrometry and 1D and 2D NMR spectroscopy. Twenty four samples from rootstocks of seventeen different Scorzonerinae taxa, comprising members of three genera (Podospermum, Scorzonera, and Tragopogon), were analyzed. Tyrolobibenzyls A (1), B (2), C (5), D (3), E (6), and F (4) were identified in crude extracts by means of HPLC retention times, on-line UV spectra and on-line MS/MS spectra. Quantification of these compounds was performed by HPLC, using 2,2-bis-(4-hydroxyphenyl)-propane as an internal standard. Tyrolobibenzyls A-F were only detected in samples from Scorzonera humilis, while chlorogenic acid and 3,5-dicaffeoylquinic acid were detected in all samples investigated. In contrast, caffeoyl tartaric acid and cichoric acid were not detectable in any member of the subtribe Scorzonerinae.

Asteraceae↗
PubMed2002

Purification, cloning, and properties of an acyltransferase controlling shikimate and quinate ester intermediates in phenylpropanoid metabolism.

A protein hydrolyzing hydroxycinnamoyl-CoA esters has been purified from tobacco stem extracts by a series of high pressure liquid chromatography steps. The determination of its N-terminal amino acid sequence allowed design of primers permitting the corresponding cDNA to be cloned by PCR. Sequence analysis revealed that the tobacco gene belongs to a plant acyltransferase gene family, the members of which have various functions. The tobacco cDNA was expressed in bacterial cells as a recombinant protein fused to glutathione S-transferase. The fusion protein was affinity-purified and cleaved to yield the recombinant enzyme for use in the study of catalytic properties. The enzyme catalyzed the synthesis of shikimate and quinate esters shown recently to be substrates of the cytochrome P450 3-hydroxylase involved in phenylpropanoid biosynthesis. The enzyme has been named hydroxycinnamoyl-CoA: shikimate/quinate hydroxycinnamoyltransferase. We show that p-coumaroyl-CoA and caffeoyl-CoA are the best acyl group donors and that the acyl group is transferred more efficiently to shikimate than to quinate. The enzyme also catalyzed the reverse reaction, i.e. the formation of caffeoyl-CoA from chlorogenate (5-O-caffeoyl quinate ester). Thus, hydroxycinnamoyl-CoA:shikimate/quinate hydroxycinnamoyltransferase appears to control the biosynthesis and turnover of major plant phenolic compounds such as lignin and chlorogenic acid.

Acyl Coenzyme A↗
PubMed2005

Biochemical study of leaf browning in minimally processed leaves of lettuce (Lactuca sativa L. var. acephala).

A series of biochemical parameters, including the concentration of total ascorbic acid (ASA(tot)) and the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidases (PODs), was investigated during cold storage (72 h at 4 degrees C in the dark) in fresh-cut (minimally processed) leaves of two lettuce (Lactuca sativa L. var. acephala) cultivars differing in the susceptibility to tissue browning: Green Salade Bowl (GSB), susceptible, and Red Salade Bowl (RSB), resistant. The two cultivars showed differences also at the biochemical level. The content in ASA(tot) increased in RSB, as a consequence of increased DHA concentration; conversely, ASA(tot) diminished in GSB, in which ASA was not detectable after 72 h of storage, thus suggesting a disappearance of ascorbate (both ASA and DHA) into nonactive forms. The antioxidant capacity (as determined by using FRAP analysis) decreased significantly during storage in RSB, while a strong increase was observed in GSB. PAL activity increased soon after processing reaching a maximum by 3 h, then it declined to a relatively constant value in RSB, while in GSB it showed a tendency to decrease in the first few hours from harvest and processing. POD activity, at least for chlorogenic acid, increased significantly during storage only in GSB.

Antioxidants↗
PubMed2004

Physiological effects and active ingredients of Viburnum dilatatum Thunb fruits on oxidative stress.

The fruit of Viburnum dilatatum Thunb, called gamazumi in Japan, showed the strong antioxidant activities, and its preventive effects on oxidative stress and active ingredients were investigated. Male rats were subjected to water immersion restraint stress for 6 hours, after ingestion of the gamazumi crude extract (GCE) for 2 weeks. The formation of gastric ulcer was reduced, and the lipid peroxidation in plasma and organs also lowered in rats ingested GCE. In the streptozotocin-induced diabetic rats given GCE for 10 weeks, inhibition of lipid peroxidation in plasma, erythrocytes and organs was observed, and the increase of plasma glucose level also lowered. On the other hand, two cyanidin glycosides, two chlorogenic acids and quercetin were identified, and especially cyanidin 3-sambubioside (Cy 3-sam) showed the strong radical scavenging activity. It is suggested that Cy 3-sam is a key compound contributing to the physiological effects of V. dilatatum fruit.

Animals↗
PubMed2004

Simultaneous determination of some active ingredients in anti-viral preparations of traditional Chinese medicine by micellar electrokinetic chromatography.

A simple and rapid micellar electrokinetic chromatography method was developed for the simultaneous determination of quercetin, gentiopicrin, forsythin, chlorogenic acid and caffeic acid in anti-viral preparations of traditional Chinese medicine (apTCM). In this method, the effects of buffer pH, concentration of the borax and SDS, organic modifiers, applied voltage and temperature on the separation were tested and discussed. The results showed that the fi ve analytes could be well separated within 11 min under conditions of 40 mM borax (pH 9.65) containing 20 mM SDS, 20 kV, at 25 degrees C. In the tested concentration range, regression equations revealed good linear relationships (correlation coefficients 0.9920-0.9991) between the peak areas and corresponding concentrations. In addition, a multiple linear regression QSPR model was constructed to predict the migration times of the analytes and the results were satisfactory. The method was validated by analysis of the five compounds in three representative apTCM samples with recoveries ranging from 89.2 to 106.6%.

Antiviral Agents↗
PubMed2005

On-column capillary electrophoretic monitoring of rapid reaction kinetics for determination of the antioxidative potential of various bioactive phenols.

An on-column capillary electrophoretic procedure for the determination of the antioxidative potential of various bioactive phenols, found in plant, fruit, and vegetable extracts, is described. The assay is based on a rapid mixing of phenols or phenolic extracts before the capillary, followed by pressurized injection of the reaction mixture into the capillary. After incubation of the reaction mixture inside the capillary, high voltage is switched on and separation of reactants and products is performed. Using hydrogen peroxide as a stressor, the kinetics of the oxidation of various bioactive phenols was studied (rutin, chlorogenic acid, quercetin, caffeic acid, gallic acid, and combinations of these) and compared with the oxidation rate of L-ascorbic acid as a reference. The concept was demonstrated for the determination of the antioxidative potential of various polyphenol mixtures and of the methanol extract of the sea buckthorn (Hippophae rhamnoides L.). In most cases quercetin has the highest rate constant of oxidation among the tested phenolic compounds. However, in the mixture L-ascorbic acid/quercetin, the oxidation rate of L-ascorbic acid was enhanced and oxidation of quercetin was strongly inhibited compared with the other combinations of tested polyphenols.

Antioxidants↗
PubMed2003

Phenolic constituents and antioxidant capacities of Crataegus monogyna (Hawthorn) callus extracts.

Crataegus (Hawthorn) has long been used as a folk medicine and is widely utilized in pharmaceutical preparations mainly because of its neuro- and cardiosedative actions and its low toxicity. The pharmacological effects of Crataegus have mainly been attributed to the polyphenolic contents. In this study, the production of polyphenols by ten-year-old Crataegus monogyna calli was studied in relation to growth variation and antioxidant capacity within a subculture period. Assays based on the Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and stability in oil-in-water emulsion were used to characterize the antioxidant actions of the callus cultures. High TEAC (3.66 micromol/g dry weight) and FRAP (208.19 micromol Fe2+/g dry weight) values were observed when maximal growth was reached(days 30-35), and this seemed to be influenced by optimum total phenol (47.40 mg/g dry weight), proanthocyanidin (20.81 mg/g dry weight), flavonoid (7.01 mg/g dry weight), anthocyanin (6.18 mg/g dry weight), (-)-epicatechin (1.77 mgl/g dry weight), procyanidin B2 (3.97 mg/g dry weight), and chlorogenic acid (1.11 mg/g dry weight) production during that period. The TEAC values were strongly associated with total flavonoids and to a lesser extent with total phenols, anthocyanins and total proanthocyanidins. The FRAP antioxidant values correlated to total phenols, proanthocyanidins and flavonoids, respectively. The polyphenolic rich calli were as effective as butylated hydroxytoluene (BHT) in preventing hydroperoxide and conjugated diene formation in a 30% oil-in-water emulsion prepared with stripped sunflower oil, during 7days storage at 30 degrees C. Crataegus monogyna cell culture represents an important alternative source for natural antioxidants.

Antioxidants↗
PubMed2003

Enzyme activity of alpha-chymotrypsin after derivatization with phenolic compounds.

Alpha-chymotrypsin was allowed to react with selected phenolic and related compounds (chlorogenic acid, m-, o-, p-dihydroxybenzene, p-benzoquinone). The derivatized enzymes obtained were characterized in terms of their activity. In vitro experiments illustrated that the enzymatic activity of the derivatives was adversely affected. The kinetics of the enzymatic reactions showed that the hydrolysis of selected food proteins becomes slower and the affinity of the enzyme to these substrates declined as measured by Michaelis-Menten constant and maximum velocity of the enzymatic reaction. This enzyme inhibition depended on the reactivity of the phenolic and related substances tested as well as on the degree of the derivatization. Further, influence of the enzyme-substrate ratio was also demonstrated. The effects of the derivatization are more pronounced with increasing concentration of the substrates.

Chymotrypsin↗
PubMed1982

Inhibitory effects of phenolics, teas and saliva on the formation of mutagenic nitrosation products of salted fish.

The objectives of this study were to simulate in vitro some of the conditions that may prevail in man during the ingestion of a meal and to quantitate the inhibitory effect of phenolics and phenolic-containing beverages on the formation of mutagenic nitrosation products. The test system consisted of nitrosating (pH 2, 1 h, 37 degrees C) an aqueous fraction of a salt-preserved Chinese fish (Pak Wik) with or without the inhibitors to be tested and estimating the frequency of his+ revertants per survivor of Salmonella typhimurium (strain TA1535). The phenolics and teas were added to the nitrosation mixture. Catechin, chlorogenic acid, gallic acid, pyrogallol and tannic acid suppressed the formation of mutagenic nitrosation products. The inhibitory efficiency was comparable to that of ascorbic acid. A Japanese, a Chinese and a Ceylonese tea also prevented the formation of mutagenic nitrosated fish products at doses which are usually consumed by man. Moreover, saliva exerted an inhibitory effect. The inhibitory effect was not additive when the phenolics or saliva were added concurrently to the nitrosation mixture. The possibility that phenolics are involved in the apparent chemopreventive effect of fruits and vegetables is discussed.

Animals↗
PubMed1992

Cholinomimetic compound distinct from caffeine contained in coffee. II: Muscarinic actions.

An extract with cholinergic activities was isolated from instant regular and decaffeinated coffees and purified. Intravenous injection of this cholinomimetic extract of coffee produced an abrupt depression in blood pressure and heart rate, changes that were distinct from those of known components of coffee, including caffeine, trigonelline, catechin, and chlorogenic acid. Pretreatment of the animals with naloxone, propranolol, isobutylmethylxanthine, hexamethonium bromide, and hemicholinium-3 chloride or bilateral vagotomy did not affect the cardiodepressive effects of the extract, whereas atropine completely abolished them. Direct injection of the cholinomimetic extract of coffee (20-100 micrograms) into the periaqueductal gray area of the midbrain did not produce any cardiovascular effect. However, the extract of coffee did cause relaxation of isolated rat and rabbit aortic ring preparations that were contracted under norepinephrine. The cholinomimetic extract did not inhibit purified acetylcholinesterase. This pharmacologic profile indicates that the cholinomimetic extract of coffee acts as a direct muscarinic agonist.

Animals↗