Search results for "CAFFEIC ACID"
showing 10 items of 49 documents
Enzyme-assisted extraction of polyphenol from edible lotus (Nelumbo nucifera) rhizome knot: Ultra-filtration performance and HPLC-MS2 profile
2018
Rhizome knot is always wasted as useless and inedible part of lotus root, despite its abundance of polyphenols. In this work, enzyme-assisted extraction followed by ultra-filtration was investigated to recover polyphenols from rhizome knot. Cellulase and pectinase treatment enhanced the polyphenols extraction. The 100 kDa membrane resulted in better filtration yield than 50 kDa membrane, 3.84% and 3.37%, respectively. With 100 kDa membrane, the highest filtration yield (4.08%) was achieved with a rotational speed of 600 rpm, TMP of 0.3 MPa and pH of 5. Satisfied permeate turbidity ( 90%) were obtained under these conditions. The main polyphenols identified in both rhizome knot extract and p…
Synthesis, chemical characterization, computational studies and biological activity of new DNA methyltransferases (DNMTs) specific inhibitor. Epigene…
2015
This work deals with the synthesis, the chemical characterization of dibutyltin(IV) complex of caffeic acid (Bu2Sn(IV)HCAF, caf1) and its cytotoxic action on tumor cells. The coordination environment at the tin center was investigated by FTIR, (119)Sn{(1)H} cross polarization magic angle spinning, electrospray ionization mass spectroscopy in the solid state and UV-vis, fluorescence and (1)H, (13)C and (119)Sn NMR spectroscopy in solution phases. Density functional theory study confirmed the proposed structures in solution phase and indicated the most probably stable conformation. The effects on viability of breast cancer MDA-MB231, colorectal cancer HCT116, hepatocellular carcinoma HepG2 an…
Gene Cloning, Transcriptional Analysis, Purification, and Characterization of Phenolic Acid Decarboxylase from Bacillus subtilis
1998
Phenolic acids, also called substituted cinnamic acids, are important lignin-related aromatic acids and natural constituents of plant cell walls. These acids (particularly ferulic, p-coumaric, and caffeic acids) bind the complex lignin polymer to the hemicellulose and cellulose in plants (1) or are generally esterified with tartaric acid (for example, in grape must, wine, and cider) and can be released as free acids during wine making by some cinnamoyl esterase activities (9). Most often, free phenolic acids are metabolized by different microorganisms into 4-vinyl derivatives and then are eventually reduced into 4-ethyl derivatives (5, 6). Some of these volatile phenols, particularly vinyl …
Photochemical and photocatalytic isomerization of trans -caffeic acid and cyclization of cis -caffeic acid to esculetin
2016
Abstract The photoisomerization of trans-caffeic acid to cis-caffeic acid has been studied in the presence of N2 in homogeneous aqueous solutions and in suspensions of various TiO2 catalysts. The results supported the hypothesis of an energy transfer process from TiO2 to the substrate due to the recombination of the photogenerated electron–hole pairs. The differences among the measured photostationary [cis]/[trans] ratios have been attributed to the different physico-chemical properties of the catalysts. In particular, the lowest ratio measured in the presence of Merck TiO2 was ascribed to the very low adsorption of trans-caffeic acid onto the surface of this sample. In the presence of O2 a…
Effects of caffeoyl conjugates of isoprenyl-hydroquinone glucoside and quinic acid on leukocyte function.
2002
The activity of three prenylhydroquinone glucosides (1-3) and four caffeoylquinic esters (4-7), obtained from Phagnalon rupestre, on elastase release, myeloperoxidase activity and superoxide and leukotriene B(4) production from polymorphonuclear leukocytes was determined. 4,5-Dicaffeoylquinic acid strongly inhibited elastase release with an IC(50) value of 4.8 microM. Methylated caffeoylquinic derivatives were the most potent inhibitors of myeloperoxidase (IC(50) near 60 microM), whereas both methylated and free carboxyl isomers inhibited superoxide production with similar potency (IC(50) between 27 and 42 microM). The monocaffeoyl conjugate of prenylhydroquinone glucoside (3), the most pot…
Arachidonate 5-lipoxygenase (ALOX5) gene polymorphism is associated with Alzheimer's disease and body mass index
2016
IF 2.126; International audience; Dementias of old age, in particular Alzheimer's disease (AD), pose a growing threat to the longevity and quality of life of individuals as well as whole societies world-wide. The risk factors are both genetic and environmental (lifestyle) and there is an overlap with similar factors predisposing to cardiovascular diseases (CVD). Using a case control genetic approach, we have identified a SNP (rs10507391) in ALOX5 gene, previously associated with an increased risk of stroke, as a novel genetic risk factor for AD. ALOX5 gene encodes a 5'-lipoxygenase (5'-LO) activating protein (FLAP), a crucial component of the arachidonic acid/leukotriene inflammatory cascad…
Effects of a water-soluble extract of rosemary and its purified component rosmarinic acid on xenobiotic-metabolizing enzymes in rat liver
2001
The effects of a water-soluble extract (WSE) of rosemary and its purified antioxidant rosmarinic acid (RA) on xenobiotic metabolizing enzymes (XME) were studied in rat liver after dietary administration. The modulation of phase I enzymes such as cytochrome P450 (CYP) 1A, 2B, 2E1, 3A, and phase II enzymes such as glutathione S-transferase (GST), quinone reductase (QR) and UDP-glucuronosyltransferase (UGT) was evaluated by measuring enzyme activities with specific substrates. Protein levels of CYPs and rGST A1/A2, A3/A5, M1, M2 and P1 were measured using antibodies in Western blots. Caffeic acid was also studied because it results from RA biotransformation in rat after oral administration. Ma…
Inhibitory effect of caffeic acid phenethyl ester, a plant-derived polyphenolic compound, on rat intestinal contractility
2009
Abstract Caffeic acid phenethyl ester (CAPE) exerts pharmacological actions (e.g. anti-inflammatory, chemopreventive) which are relevant for potential clinical application in the digestive tract. However, no study has been published on its possible effects on intestinal motility, to date. In the present study, we investigated the effect of this plant-derived polyphenolic compound on the spontaneous contractions of the rat isolated ileum. CAPE reduced (in a tetrodotoxin-insensitive manner) spontaneous ileal contractions and this effect was reduced by the l -type Ca 2+ channel blocker nifedipine and the chelant of calcium ethylenediaminetetraacetic acid. However, the effect of CAPE was not mo…
Food quality and nutraceutical value of nine cultivars of mango (Mangifera indica L.) fruits grown in Mediterranean subtropical environment
2019
Mango (Mangifera indica L.) quality is strongly influenced by genotype but individuating the most appropriate harvesting time is essential to obtain high quality fruits. In this trial we studied the influences of the ripening stage at harvest (mature-ripe or green-ripe) on quality of ready to eat mango fruits from nine cultivars (Carrie, Keitt, Glenn, Manzanillo, Maya, Rosa, Osteen, Tommy Atkins and Kensington Pride) grown in the Mediterranean subtropical climate through physicochemical, nutraceutical, and sensory analysis. Our results show a large variability among the different observed genotypes and in dependence of the ripening stage at harvest. With the exception of Rosa, mature-ripe f…
Electrochemical detection of the 2-isobutyl-3-methoxypyrazine model odorant based on odorant-binding proteins: The proof of concept
2014
Abstract We developed an electrochemical assay for the detection of odorant molecules based on a rat odorant-binding protein (rOBP3). We demonstrated that rOBP3 cavity binds 2-methyl-1,4-naphtoquinone (MNQ), an electrochemical probe, as depicted from the decrease of its electrochemical signal, and deduced the dissociation constant, Kd MNQ = 0.5(± 0.2) μM. The amount of MNQ displaced from rOBP3 by 2-isobutyl-3-methoxypyrazine (IBMP), a model odorant molecule, was measured using square-wave voltammetry. The release of MNQ by competition led to an increase of the electrochemical response. In addition, this method allowed determination of the dissociation constant of rOBP3 for IBMP, Kd IBMP =…