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 163 records · Page 9Linked to original sources
PubMed1999

Antioxidant flavonoids and chlorogenic acid from the leaves of Eriobotrya japonica.

The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at 37 degrees C, using 2-thiobarbituric acid (TBA). The methanol extract and its fractions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction, and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and 2 alpha-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.

Animals↗
PubMed2005

Chlorogenic acid moderately decreases the quality of whey proteins in rats.

During processing and storage, phenolic compounds (PCs) may react with food protein bound amino acids (AAs). Such reactions have been reported to change physicochemical and to decrease in vitro digestion properties of proteins. A rat growth and nitrogen (N) balance study was conducted to prove whether derivatization with chlorogenic acid (CA) affects the nutritional quality of beta-lactoglobulin (beta-LG). Test diets (10% protein level) contained nonderivatized beta-LG (LG, treated under omission of CA), low derivatization level beta-LG (LGL), high derivatization level beta-LG (LGH), or casein supplemented with l-methionine (0.3% of diet; C+met) as an internal standard. An additional group received untreated beta-LG supplemented with pure CA (1.03% of diet; LG+CA). The AA composition of test proteins, plasma AAs, and liver glutathione (GSH) concentrations were determined. Protein digestibility-corrected amino acid score (PDCAAS) was calculated using human or rat AA requirement patterns and rat fecal digestibility values. N excretion was significantly higher in feces and lower in urine of rats fed with LGH as compared to LG and LGL. Consequently, true N digestibility (TND) was significantly lower with LGH as compared to LG and LGL. The lower content of methionine, cysteine, lysine, and tryptophan in LGH corresponded to a reduced TND. Net protein utilization (NPU) was not different between treated beta-LG fed diet groups but was lower than in LG+CA and C+met fed groups. Only at a relatively high level of derivatization with CA, the otherwise good nutritional quality of beta-LG is affected so that TND is reduced, while NPU still remains unaffected. Derivatization of beta-LG with CA does not seem to lead to an additional deficiency in a specific indispensable AA in growing rats fed with 10% protein.

Amino Acids↗
PubMed1997

Chlorogenic acid and hydroxynitrobenzaldehyde: new inhibitors of hepatic glucose 6-phosphatase.

We have studied the interactions of chlorogenic acid (CHL) and 2-hydroxy-5-nitrobenzaldehyde (HNB) with the components of the rat hepatic glucose 6-phosphatase (Glc-6-Pase) system. CHL and HNB are competitive inhibitors of glucose 6-phosphate (Glc-6-P) hydrolysis in intact microsomes with Ki values of 0.26 and 0.22 mm, respectively. CHL is without effect on the enzyme of fully disrupted microsomes or the system inorganic pyrophosphatase (PPiase) activity. HNB is a potent competitive inhibitor of the system PPiase activity (Ki = 0.56 mm) and a somewhat weaker noncompetitive inhibitor of enzyme activity (Ki = 2.1 mm). These findings indicate CHL binds to T1, the Glc-6-P transporter, and HNB inhibits through interaction with both T1 and T2 the phosphate (Pi)-PPi transporter. Binding of CHL and HNB is freely reversible. However, the inhibition of both PPiase and Glc-6-Pase by HNB becomes irreversible following incubation of HNB-exposed microsomes with 2.5 mm sodium borohydride, indicating that inhibition involves the formation of a Schiff base. The presence of CHL effectively protects T1, but not T2, against the irreversible inhibition by HNB. In contrast, PPi and Pi are effective in protecting T2, but not T1. This is the first report describing an effective inhibitor of the system PPiase activity (T2). CHL is the most specific T1 inhibitor described to date.

Animals↗
PubMed2005

A high performance liquid chromatography method for the simultaneous determination of arctiin, chlorogenic acid and glycyrrhizin in a Chinese proprietary medicine.

A high performance liquid chromatography (HPLC) method was developed for the simultaneous determination of arctiin, chlorogenic acid and glycyrrhizin in the tablets of a Chinese proprietary medicine named, "Yin Qiao Jie Du Pian". The analysis was performed by a reverse phase gradient elution, using an aqueous mobile phase (containing 0.4% acetic acid and 4.5% tetrahydrofuran) modified by acetonitrile and detection made simultaneously at three wavelengths. The method was validated for specificity, accuracy, precision and limits of detection and quantification. Tablets of seven commercial brands were analyzed and found to contain different amounts of the three bioactive markers. This raised the question of the quality and the efficacy of the products. The method developed can be used for the quality control of "Yin Qiao Jie Du" tablets.

Acetic Acid↗
PubMed2005

Association analysis of candidate genes for maysin and chlorogenic acid accumulation in maize silks.

Two compounds, the C-glycosyl flavone maysin and the phenylpropanoid product chlorogenic acid (CGA), have been implicated in corn earworm (Helicoverpa zea Boddie) resistance in maize (Zea mays L.). Previous quantitative trait locus (QTL) analyses identified the pericarp color (p) locus, which encodes a transcription factor, as the major QTL for maysin and CGA. QTL analysis has also implicated the dihydroflavanol reductase (DFR; E.C. no. 1.1.1.219) locus anthocyaninless1 (a1) and the duplicate chalcone synthase (CHS; E.C. no. 2.3.1.74) loci colorless2 (c2) and white pollen1 (whp1) as genes underlying QTL for maysin and/or CGA synthesis. Epistatic interactions between p and a1 and between p and c2 were also defined. CHS catalyzes the first step in the flavonoid pathway and represents one of the first enzyme steps following the branch off the general phenylpropanoid pathway towards CGA synthesis. In maize, the reduction of dihydroflavanol to leucoanthocyanin by DFR immediately follows the pathway branch leading to C-glycosyl flavone production. The detection of QTLs for maysin and CGA concentration at loci encoding enzyme steps following the pathway branch points implicates alterations in the flow of biochemical intermediates as the biological basis of the QTL effects. To examine if sequence variation among alleles of a1, c2, and whp1 affect maysin and CGA synthesis in maize silks, we performed an association analysis. Because the p locus has often been a major QTL for maysin and CGA and has exhibited epistatic interactions with a1, c2, and whp1, association analysis was conditioned on the p genotype. A highly significant association of two sequence polymorphisms in the promoter of a1 with maysin synthesis was demonstrated. Additional conditioning on the genotype of the significant a1 polymorphism allowed the detection of a significant polymorphism within the whp1 promoter. Our analyses demonstrate that conditioning for epistatic factors greatly increases the power of association testing.

Animals↗
PubMed1997

[Sample pretreatment method for assay of chlorogenic acid in Chinese medicinal preparations].

This paper introduces a sample pretreatment method for assaying chlorogenic acid-D101-column separation-precipitation method. The method features thorough removal of impurities, complete separation of chlorogenic acid and simple operational procedures. The experimental result of four samples from three preparations shows that this method is good in reliability and applicability.

Chlorogenic Acid↗
PubMed2002

Isolation and characterization of undenatured chlorogenic acid free sunflower (Helianthus annuus) proteins.

A method for obtaining sunflower protein (SFP) isolate, nondenatured and free of chlorogenic acid (CGA), has been developed. During the isolating procedure, the extent of CGA removal and protein denaturation was monitored. The defatted flour contained 2.5% CGA as the main phenolic compound. Phenolic compounds were removed by aqueous methanol (80%) extraction, before protein extraction at alkaline pH and diafiltration. Differential scanning calorimetry and solubility tests indicated that no denaturation of the proteins had occurred. The resulting protein products were biochemically characterized, and the presence of protein-CGA complexes was investigated. SFPs of the studied variety were found to be composed of two main protein fractions: 2S albumins and 11S globulins. In contrast to what has been previously reported, CGA was found to elute as free CGA, not covalently associated to any protein fraction.

Albumins↗
PubMed2004

Effects of chlorogenic acid, an active compound activating calcineurin, purified from Flos Lonicerae on macrophage.

AIM: To investigate the activation of chlorogenic acid (CHA) purified from Flos Lonicerae to calcineurin and its effects on macrophage functions in vivo and in vitro. METHODS: According to the screening results that Flos Lonicerae could activate calcineurin, the active component which could activate calcineurin was purified from Flos Lonicerae by column chromatography on silica gel and identified as CHA. The activation of CHA on calcineurin had been validated with both p-NPP and 32P-labeled RII peptide as the substrates. The clearance of charcoal particles in normal mice and the cytotoxicity of U937 to MCF-7 were used together to determine the effects of CHA on macrophage functions. RESULTS: CHA could activate calcineurin, and the concentration of CHA on maximal activating calcineurin was 282.5 micromol/L. CHA administration (10 mg/kg, ig, 7 d) significantly enhanced the macrophage functions in normal mice. CHA (70.6, 141.2, and 282.5 micromol/L) obviously increased the cytotoxicity of U937 to MCF-7. CONCLUSION: CHA could activate calcineurin and enhance the macrophage functions in vivo and in vitro, and its functions in vivo may be realized via the signal pathways of calcineurin.

Animals↗
PubMed1999

Suppressive effects of chlorogenic acid on N-methyl-N-nitrosourea-induced glandular stomach carcinogenesis in male F344 rats.

The modifying effects of chlorogenic acid (CA) on N-methyl-N-nitrosourea (MNU)-induced glandular stomach carcinogenesis were investigated in five groups of male F344 rats. Rats in Groups 1 through 3 were given MNU in drinking water at a concentration of 400 ppm for 12 weeks. Animals of Group 1 were then kept on the basal diet alone, and those of Group 2 or 3 were fed a diet containing 500 or 250 ppm CA for a subsequent 22 weeks. Group 4 was exposed to CA alone through the experimental period (36 weeks), and Group 5 was given the basal diet continuously and treated as a control. At the end of the experiment, the incidence of glandular stomach carcinoma of Group 3 was significantly smaller than that of Group 1 (p < 0.03). The incidence of adenomatous hyperplasia of Group 2 was also significantly lower than that of Group 1 (p < 0.02). In addition, the proliferating cell nuclear antigen (PCNA) labeling index of the epithelial cells from the non-neoplastic mucosa in rats of Group 2 or 3 was significantly smaller than that of Group 1 (p < 0.0001). These results suggest that CA has a chemopreventive effect on MNU-induced rat glandular stomach carcinogenesis by exposure during the post-initiation phase, and CA may be a promising agent for prevention of human stomach cancer.

Animals↗
PubMed2001

Chlorogenic acids as a potential criterion in coffee genotype selections.

A systematic study by HPLC was conducted to determine the content of chlorogenic acids in green coffee beans of the Variedad Colombia (Coffea arabica Caturra var. x Híbrido de Timor) and in other genotypes of interest of C. arabica, Coffea canephora, Híbrido de Timor, and the F1 offspring derived from the crossing Caturra x Híbrido de Timor. Comparisons were made of the total content of these acids, their quantitative differences, and the presence or absence of some of them, using parametric statistical techniques and multivariate analysis. Total content differences were found between C. canephora accessions, between Típica and Caturra varieties of C. arabica, and between Híbrido de Timor accessions. The chromatographic profile comparisons with principal component analysis separated in the first component C. canephora accessions from the rest of the genotypes, whereas the second component separated C. canephora accessions.

Chlorogenic Acid↗
PubMed2004

Engineering plants with increased levels of the antioxidant chlorogenic acid.

The trend to view many foods not only as sustenance but also as medicine, so-called functional foods, is increasing. Phenolics are the most widespread dietary antioxidants, and among these, chlorogenic acid (CGA) accumulates to high levels in some crop plants. CGA acts as an antioxidant in plants and protects against degenerative, age-related diseases in animals when supplied in their diet. cDNA clones encoding the enzyme that synthesizes CGA, hydroxycinnamoyl-CoA quinate: hydroxycinnamoyl transferase (HQT), were characterized from tomato and tobacco. Gene silencing proved HQT to be the principal route for accumulation of CGA in solanaceous species. Overexpression of HQT in tomato caused plants to accumulate higher levels of CGA, with no side-effects on the levels of other soluble phenolics, and to show improved antioxidant capacity and resistance to infection by a bacterial pathogen. Tomatoes with elevated CGA levels could be used in foods with specific benefits for human health.

Acyl Coenzyme A↗
PubMed1998

Chlorogenic acid analogue S 3483: a potent competitive inhibitor of the hepatic and renal glucose-6-phosphatase systems.

S 3483, a synthetic derivative of chlorogenic acid (CHL), was found to be a reversible, linear competitive inhibitor of the glucose-6-phosphatase (Glc-6-Pase) system in rat renal microsomes and rat and human liver microsomes. The Ki for S 3483 in rat liver microsomes (129 nM) is three orders of magnitude smaller than the Ki for CHL. S 3483 up to 100 microM had no effect on the Glc-6-Pase enzyme activity or on the system inorganic pyrophosphatase activity (i.e., on T2, the Pi/inorganic pyrophosphate transporter). Thus, like CHL, S 3483 appears to be a site-specific inhibitor of T1, the Glc-6-P transporter of renal and liver microsomes. The potency of S 3483 was unaffected when the ratio Vmax(T1):Vmax(enzyme) was altered over a 10-fold range by applying enzyme inhibition and selective inactivation of T1. The absence of T1-imposed rate restrictions on the potency of reversible T1 inhibitors contrasts markedly with the response of reversible Glc-6-Pase enzyme inhibitors, whose potency declines sharply as T1 becomes more rate controlling. The potency of S 3483, but not of CHL, decreased as the microsomal protein concentration in the assay medium was increased. This effect suggests that as the protein concentration was raised the concentration of T1 in the assay medium approached the order of magnitude of the Ki for S 3483. Thus, the microsomal content of T1 is likely to be on the order of 100 pmol/mg protein. S 3483 is the most potent inhibitor of the Glc-6-Pase system reported to date. It and other tight-binding inhibitors of T1 will provide useful new tools for investigating the molecular structure and physiology/pathology of the Glc-6-Pase system.

Animals↗