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Sample records for catechin

  1. (+/-)-catechin: chemical weapon, antioxidant, or stress regulator?

    Science.gov (United States)

    Chobot, Vladimir; Huber, Christoph; Trettenhahn, Guenter; Hadacek, Franz

    2009-08-01

    (+/-)-Catechin is a flavan-3-ol that occurs in the organs of many plant species, especially fruits. Health-beneficial effects have been studied extensively, and notable toxic effects have not been found. In contrast, (+/-)-catechin has been implicated as a 'chemical weapon' that is exuded by the roots of Centaurea stoebe, an invasive knapweed of northern America. Recently, this hypothesis has been rejected based on (+/-)-catechin's low phytotoxicity, instability at pH levels higher than 5, and poor recovery from soil. In the current study, (+/-)-catechin did not inhibit the development of white and black mustard to an extent that was comparable to the highly phytotoxic juglone, a naphthoquinone that is allegedly responsible for the allelopathy of the walnut tree. At high stress levels, caused by sub-lethal methanol concentrations in the medium, and a 12 h photoperiod, (+/-)-catechin even attenuated growth retardation. A similar effect was observed when (+/-)-catechin was assayed for brine shrimp mortality. Higher concentrations reduced the mortality caused by toxic concentrations of methanol. Further, when (+/-)-catechin was tested in variants of the deoxyribose degradation assay, it was an efficient scavenger of reactive oxygen species (ROS) when they were present in higher concentrations. This antioxidant effect was enhanced when iron was chelated directly by (+/-)-catechin. Conversely, if iron was chelated to EDTA, pro-oxidative effects were demonstrated at higher concentrations; in this case (+/-)-catechin reduced molecular oxygen and iron to reagents required by the Fenton reaction to produce hydroxyl radicals. A comparison of cyclic voltammograms of (+/-)-catechin with the phytotoxic naphthoquinone juglone indicated similar redox-cycling properties for both compounds although juglone required lower electrochemical potentials to enter redox reactions. In buffer solutions, (+/-)-catechin remained stable at pH 3.6 (vacuole) and decomposed at pH 7.4 (cytoplasm

  2. Structural Properties of Green Tea Catechins

    OpenAIRE

    Botten, Dominic; Fugallo, Giorgia; Fraternali, Franca; Molteni, Carla

    2015-01-01

    Green tea catechins are polyphenols which are believed to provide health benefits; they are marketed as health supplements and are studied for their potential effects on a variety of medical conditions. However, their mechanisms of action and interaction with the environment at the molecular level are still not well-understood. Here, by means of atomistic simulations, we explore the structural properties of four green tea catechins, in the gas phase and water solution: specifically, (-)-epiga...

  3. Structural Properties of Green Tea Catechins.

    Science.gov (United States)

    Botten, Dominic; Fugallo, Giorgia; Fraternali, Franca; Molteni, Carla

    2015-10-01

    Green tea catechins are polyphenols which are believed to provide health benefits; they are marketed as health supplements and are studied for their potential effects on a variety of medical conditions. However, their mechanisms of action and interaction with the environment at the molecular level are still not well-understood. Here, by means of atomistic simulations, we explore the structural properties of four green tea catechins, in the gas phase and water solution: specifically, (-)-epigallocatechin-3-gallate, which is the most abundant, (-)-epicatechin-3-gallate, (-)-epigallocatechin-3-O-(3-O-methyl)-gallate, and (-)-epigallocatechin. We characterize the free energy conformational landscapes of these catechins at ambient conditions, as a function of the torsional degrees of freedom of the pholyphenolic rings, determining the stable conformers and their connections. We show that these free energy landscapes are only subtly influenced by the interactions with the solvent and by the structural details of the polyphenolic rings. However, the number and position of the hydroxyl groups (or their sustituents) and the presence/absence of the galloyl moiety have significant impact on the selected catechin solvation shells and hydrogen bond capabilities, which are ultimately linked to their ability to interact with and affect the biological environment. PMID:26369298

  4. Extraction of Catechins from Green Tea Using Ultrasound

    Science.gov (United States)

    Koiwai, Hitoshi; Masuzawa, Nobuyoshi

    2007-07-01

    Recently, hazardous properties of synthetic substances contained in foods and medicines have been observed. Therefore, the pharmacological actions of natural substances became the focus of attention. Catechins, which are polyphenols, are abundant in green tea. To extract green tea catechins, there are two types of method: extraction using hot water and organic solvents. In the extraction using hot water, green tea quality deteriorates and catechins are destroyed due to the heat applied. Accordingly, the extraction of catechins at low temperatures is appropriate, although the efficiency is low. Therefore, we attempted to increase the amount of catechins extracted with ultrasonic irradiation.

  5. Interactions between milk fat globules and green tea catechins.

    Science.gov (United States)

    Rashidinejad, Ali; Birch, E John; Everett, David W

    2016-05-15

    The determination of putative chemical interactions between the milk fat globule membrane and green tea catechins provided useful information about the role of milk fat globules (MFGs) in high-fat dairy systems, such as cheese, and containing bioactive compounds, such as tea catechins. Catechins from green tea (125-1000ppm), including (+)-catechin, (-)-epigallocatechin gallate, and green tea extract were added to washed MFGs to examine possible interactions. The addition of catechins gave a significant change in the size and ζ-potential of MFGs. The recovery of different catechins from the milk fat globule suspensions was found to vary, suggesting selective association with the milk fat globule membranes. The interactions were further investigated using transmission electron microscopy and Fourier transform infra-red spectroscopy. It is suggested that catechins are localised in association with milk fat globule membrane domains as they contain both hydrophobic and hydrophilic moieties with potential points of molecular interaction. PMID:26775981

  6. Catechin content and consumption ratio of the collared lemming

    DEFF Research Database (Denmark)

    Berg, Thomas B.

    2003-01-01

    . Enclosures with the first three species mentioned were further treated by clipping to simulate herbivory in order to induce the production of the plant defence compound catechin. Treatment increased the catechin content in Dryas spp., S. arctica (females only) and V. uliginosum significantly compared with...

  7. Green tea catechins: defensive role in cardiovascular disorders

    Institute of Scientific and Technical Information of China (English)

    Pooja Bhardwaj; Deepa Khanna

    2013-01-01

    Green tea,Camellia sinensis (Theaeeae),a major source of flavonoids such as catechins,has recently shown multiple cardiovascular health benefits through various experimental and clinical studies.These studies suggest that green tea catechins prevent the incidence of detrimental cardiovascular events,and also lower the cardiovascular mortality rate.Catechins present in green tea have the ability to prevent atherosclerosis,hypertension,endothelial dysfunction,ischemic heart diseases,cardiomyopathy,cardiac hypertrophy and congestive heart failure by decreasing oxidative stress,preventing inflammatory events,reducing platelet aggregation and halting the proliferation of vascular smooth muscle cells.Catechins afford an anti-oxidant effect by inducing anti-oxidant enzymes,inhibiting pro-oxidant enzymes and scavenging free radicals.Catechins present anti-inflammatory activity through the inhibition of transcriptional factor NF-κB-mediated production of cytokines and adhesion molecules.Green tea catechins interfere with vascular growth factors and thus inhibit vascular smooth muscle cell proliferation,and also inhibit thrombogenesis by suppressing platelet adhesion.Additionally,catechins could protect vascular endothelial cells and enhance vascular integrity and regulate blood pressure.In this review various experimental and clinical studies suggesting the role of green tea catechins against the markers of cardiovascular disorders and the underlying mechanisms for these actions are discussed.

  8. Nature of pectin-protein-catechin interactions in model systems: pectin-protein-catechin interactions.

    Science.gov (United States)

    Zhao, Guang-Yuan; Diao, Hua-Juan; Zong, Wei

    2013-04-01

    Apple pectins, proteins and catechins were combined in model systems, and the resulting hazes were measured by spectrophotometric method, a zeta potential and particle size analyzer and Ostwald viscosimeter. The amount of hazes formed depends on the concentrations of both protein and pectin. The cooperative hydrogen bonding between the numerous hydroxyl groups of pectins and hydrone and the gel-like structure developed by pectin induced the solvation or solubilization of polymers, and the protein molecule has a fixed number of polyphenol binding sites. The influence of pectin relative molecular mass and degree of esterification on the formation of suspended particles is prominent, and this makes the number of hydroxyl groups and charge of pectin which is concerned with combining protein and catechin to change a lot. More haze was observed when model systems were heated, suggesting that hydrophobic groups of protein are beneficial to their binding with phenols and pectins. The pH value affects the charged state of the protein and pectin, which influences the combination of pectin-gliadin-catechin. PMID:23382557

  9. Simple thin layer chromatography (TLC) methods for the separation of catechins from fresh tea leaves

    International Nuclear Information System (INIS)

    Techniques for separating seven catechins on two adsorbents on thin layer chromatography(TLC) layers were investigated. One of the TLC methods used was fast and gave good resolution of the catechins. Both methods showed that the Rfs of one group of the catechins were related to their structural variations. Thus the methods could be used for the tentative identification of catechins in tea as well as in routine screening of catechins in other plants. (author)

  10. Allelopathic potential of catechins of the Tachigali myrmecophyla (Leguminosae)

    International Nuclear Information System (INIS)

    Two compounds, (+)-catechin and epicatechin, were isolated from leaves of T. myrmecophyla, using chromatographic techniques. The structural identification was carried out on the basis of 1H and 13C NMR spectral data and comparison with literature data. The compounds (+)-catechin and epicatechin were submitted to germination inhibition and radicle and hypocotyl growth assays. Results showed some significant activities confirming the initial hypothesis about allelopathic properties of that plant. (author)

  11. Selective toxicity of Catechin-a natural flavonoid towards bacteria.

    Science.gov (United States)

    Fathima, Aafreen; Rao, Jonnalagadda Raghava

    2016-07-01

    Catechin is a plant polyphenol composed of epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) as diastereoisomers. Among the various classes of flavonoids, catechin was found to be the most powerful free radical scavenger, scavenging the reactive oxygen species (ROS) generated due to oxidative damage with antibacterial and anti-inflammatory activity. The toxicity of catechin towards bacteria was studied using gram-positive bacteria (B. subtilis) and gram-negative bacteria (E. coli) as model organisms and was found to be more toxic towards gram-positive bacteria. From the results, catechin was found to be beneficial as well as toxic (inhibitory) to the bacteria at a selective concentration behaving as double-edged swords with an IC50 value of 9 ppm for both the bacteria. The inhibitory mechanism of catechin was by oxidative damage through membrane permeabilization which was confirmed by the formation and treatment of bacterial liposomes. SEM images of the control and treated bacteria reveals membrane damage with morphological changes. PMID:27052380

  12. Sulphation of the flavonoids quercetin and catechin by rat liver.

    Science.gov (United States)

    Shali, N A; Curtis, C G; Powell, G M; Roy, A B

    1991-07-01

    1. The isolated perfused rat liver forms three sulphated metabolites from each of the flavonoids, quercetin and catechin: these are secreted into the bile and the perfusate. 2. Quercetin gives two double conjugates, containing sulphate and glucuronic acid, and one sulphate: catechin gives one such double conjugate and two sulphates. 3. This sulphation is not inhibited by 60 microM 2,6-dichloro-4-nitrophenol which almost completely inhibits the sulphation of harmol in this perfused liver system. 4. The sulphation of harmol by the perfused liver is not inhibited by the flavonoids. 5. Unfractionated sulphotransferases from rat liver catalyse sulphate conjugation of quercetin and catechin in vitro by a reaction inhibited by pentachlorophenol or dichloronitrophenol: the flavonoids inhibit the sulphation of 4-nitrophenol by this system. 6. The results with the two systems are discussed and shown to be compatible. PMID:1776264

  13. Effects of green tea catechins on gramicidin channel function and inferred changes in bilayer properties

    NARCIS (Netherlands)

    Ingólfsson, Helgi I; Koeppe, Roger E; Andersen, Olaf S

    2011-01-01

    Green tea's health benefits have been attributed to its major polyphenols, the catechins: (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), and epicatechin (EC). Catechins (especially EGCG) modulate a wide range of biologically important molecules, inclu

  14. (±)-Catechin: Chemical Weapon, Antioxidant, or Stress Regulator?

    OpenAIRE

    Chobot, Vladimir; Huber, Christoph; Trettenhahn, Guenter; Hadacek, Franz

    2009-01-01

    (±)-Catechin is a flavan-3-ol that occurs in the organs of many plant species, especially fruits. Health-beneficial effects have been studied extensively, and notable toxic effects have not been found. In contrast, (±)-catechin has been implicated as a ‘chemical weapon’ that is exuded by the roots of Centaurea stoebe, an invasive knapweed of northern America. Recently, this hypothesis has been rejected based on (±)-catechin’s low phytotoxicity, instability at pH levels higher than 5, and poor...

  15. Antioxidant Effects of Quercetin and Catechin Encapsulated into PLGA Nanoparticles

    OpenAIRE

    Pool, Hector; Quintanar, David; Figueroa, Juan de Dios; Marinho Mano, Camila; Bechara, J. Etelvino H.; Godínez, Luis A.; Mendoza, Sandra

    2012-01-01

    Polymeric nanoparticles (PLGA) have been developed for the encapsulation and controlled release of quercetin and catechin. Nanoparticles were fabricated using a solvent displacement method. Physicochemical properties were measured by light scattering, scanning electron microscopy and ζ-potential, X-ray diffraction, infrared spectroscopy and differential scanning calorimetry. Encapsulation efficiency and in vitro release profiles were obtained from differential pulse voltammetry experiments. A...

  16. Chemiluminescence assay for catechin based on generation of hydrogen peroxide in basic solution

    International Nuclear Information System (INIS)

    We have determined that the catechin group in basic solution efficiently produces hydrogen peroxide; moreover, a highly sensitive analysis methodology was developed to measure catechin employing a peroxalate chemiluminescence detection system. Identification of hydrogen peroxide generated by catechin was determined by ESR as well as peroxalate chemiluminescence using catalase and SOD. As a result, catechin-generated superoxide by electron reduction to dissolved oxygen in basic solution, followed by production of hydrogen peroxide through dismutation reaction. This method could measure several tea catechins, (+)-catechin (CC), (-)-epigallocatechin-3-gallate (EGCg), (-)-epicatechin-3-gallate (ECG) and gallic acid, with measurement range from 10-7 to 10-3 mol/l and sensitivity of 10-8 mol/l. This method was also applied to the determination of total catechin levels in green tea, black tea and roasted green tea

  17. Excretion of Four Catechins in Tea Polyphenols in Rats

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective To investigate excretion profiles of the four major anti-oxidant active catechins, (-) epigallo-catechin-3-gallate (EGCG), (-) epicatechin-3-gallate (ECG), (-) epigallocatechin (EGC), and epicatechin (EC) in tea polyphenols (TP) in rats in order to provide experimental data for clinical uses and development of TP as a novel drug. Methods The above four catechins in urine, bile, and feces were simultaneously determined by high performance liquid chromatography coupled with ultraviolet absorption detector (HPLC-UV) assay with a binary gradient elution. The samples were extracted by ethyl acetate prior to HPLC. The quantification was carried out by peak area internal standard method. Following iv dosing TP 100 mg/kg to rats, the samples were collected at different time intervals up to 8 h (urine and bile) and 24 h (feces). Results The urinary Ae, 0-8 h (cumulative excretion amount over 8 h) of EGCG, ECG, EGC, and EC were, on the average, 150.83, 30.75, 116.69, and 254.56 μg, corresponding to fe, 0-8 h (cumulative excretion fraction of dose over 8 h) of 1.45%, 0.84%, 7.88%, and 10.73%, respectively; the biliary Ae, 0-8 h were 12.61, 42.64, 6.61, and 1.24 μg, corresponding to the fe, 0-8 h of 0.12%, 1.16%, 0.45%, and 0.053%,respectively. For fecal excretion, only EGCG and EGC were detected with Ae, 0-24 h of 7.38 μg (fe, 0-24 h of 0.07%) and 157 μg (fe, 0-24 h of 9.99 %), respectively. The fe, total (the total fe of 3 excretory routes) were 18.32%, 10.78%, 2.00%, and 1.64% for EGC, EC, ECG, and EGCG, respectively. Conclusion EGCG and EC are mainly excreted in urine, ECG in bile, and EGC in feces by reference to their Ae and fe. The excretion of the four catechins based on fe, total is ranked in order of EGC > EC > ECG > EGCG. Only small amount of four catechins are recovered in urine, bile, and feces, indicating an extensive metabolic conversion of catechins in the rat body.

  18. Subcellular Localization of Galloylated Catechins in Tea Plants (Camellia sinensis (L. O. Kuntze Assessed via Immunohistochemistry

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    Huanhuan eXu

    2016-05-01

    Full Text Available Galloylated catechins, as the main secondary metabolites in the tea plant, including (--epigallocatechin-3-gallate and (--epicatechin-3-gallate, comprise approximately three-quarters of all the tea plant catechins and have stronger effects than non-galloylated catechins, both on the product quality in tea processing and the pharmacological efficacy to human beings. The subcellular localization of galloylated catechins has been the primary focus of studies that assess biosynthesis and physiological functions. Classical histochemical localization staining reagents can not specifically detect galloylated catechins; thus, their subcellular localization remains controversial. In the present study, we generated a monoclonal antibody (mAb against galloylated catechins, which can be used for the subcellular localization of galloylated catechins in the tea plant by immunohistochemistry. Direct ELISA and ForteBio Octet Red 96 System assay indicated the mAb could recognize the galloylated catechins with high specificities and affinities. In addition, tea bud was ascertained as the optimal tissue for freezing microtomic sections for immunohistochemistry. What’s more, the high quality mAbs which exhibited excellent binding capability to galloylated catechins were utilised for the visualization of them via immunohistochemistry. Our findings demonstrated that vacuoles were the primary sites of localization of galloylated catechins at the subcellular level.

  19. The effects of green tea derived catechins upon adipocyte metabolism

    OpenAIRE

    Mehra, Anisha

    2010-01-01

    Tea, from the plant Camellia Sinensis, is after water, the most consumed drink in the world. Green tea, produced by steaming freshly harvested leaves to prevent fermentation, is high in polyphenols known as catechins or flavanols. The major flavanols found in green tea include (-) epigallocatechin-3-gallate (EGCG) and (-) epicatechin. Literature reports suggest that green tea flavanols have the potential to exert anti-obesity effects by modulating weight gain and other factors such as lipogen...

  20. Preparation of 14C-catechins by tea cell culture

    International Nuclear Information System (INIS)

    The preparation of 14C labelled catechins was studied by feeding 14C labelled precursor to tea cultured cells. Two labelled precursors were tested and their effects were compared. The dynamics of absorption and transformation of fed precursors were analyzed and the effects of pre-culture as well as UV light pretreatment on product labelling rate were evaluated. Product analysis was also made by HSCCC and HPLC techniques

  1. Metabolism of green tea catechins in the human small intestine

    OpenAIRE

    Schantz, Markus; Erk, Thomas; Richling, Elke

    2010-01-01

    Abstract Numerous studies have shown that green tea polyphenols can be degraded in the colon, and there is abundant knowledge about the metabolites of these substances that appear in urine and plasma after green tea ingestion. However, there is very little information on the extent and nature of intestinal degradation of green tea catechins in humans. Therefore, the aim of this study presented here was to examine in detail the microbial metabolism and chemical stability of these po...

  2. Antimicrobial activity of Gel-entrapped catechins toward oral microorganisms.

    Science.gov (United States)

    Tamura, Muneaki; Saito, Hideo; Kikuchi, Kuniyoshi; Ishigami, Tomohiko; Toyama, Yoshio; Takami, Masao; Ochiai, Kuniyasu

    2011-01-01

    The oral cavity contains almost half of the commensal bacterial population present in the human body. An increase in the number of these microorganisms may result in systemic diseases such as infective endocarditis and aspiration pneumonia as well as oral infections. It is essential to control the total numbers of these microorganisms in order to suppress disease onset. Thus, we examined the antimicrobial activity of a newly developed gel-entrapped catechin (GEC) preparation against oral microorganisms. The minimum inhibitory concentration (MIC) of GEC was determined based on the relationship between a modified agar diffusion method and a broth microdilution method. GEC inhibited the growth of the Actinomyces, periodontopathic bacteria and Candida strains tested, but did not inhibit the growth of the oral streptococci that are important in the normal oral flora. Commercially available moisture gels containing antimicrobial components showed antimicrobial activity against all of the tested strains. After a series of washes and after a 24-h incubation, GEC retained the antimicrobial activity of the catechins. Catalase prevented GEC-induced growth inhibition of Actinomyces naeslundii and Streptococcus mutans suggesting that hydrogen peroxide may be involved in the antimicrobial activity of catechins. These results suggest that GEC may be useful for controlling oral microorganism populations and reducing the accumulation of dental plaque, thereby helping to prevent periodontal disease and oral candidiasis. PMID:21532150

  3. Density Functional Theory Study on Interaction between Catechin and Thymine

    Institute of Scientific and Technical Information of China (English)

    Wan-fei Cai; Yan Zheng; Lai-cai Li; An-min Tian

    2012-01-01

    The interacting patterns and mechanism of the catechin and thymine have been investigated with the density functional theory Becke's three-parameter nonlocal exchange functional and the Lee,Yang,and Parr nonlocal correlation functional (B3LYP) method by 6-31+G* basis set.Thirteen stable structures for the catechin-thymine complexes have been found which form two hydrogen bonds at least.The vibrational frequencies are also studied at the same level to analyze these complexes.The results indicated that catechin interacted with thymine by three different hydrogen bonds as N-H…O,C-H…O,O-H…O and the complexes are mainly stabilized by the hydrogon bonding interactions.Theories of atoms in molecules and natural bond orbital have been adopted to investigate the hydrogen bonds involved in all systems.The interaction energies of all complexes have been corrected for basis set superposition error,which are from-18.15 kJ/mol to 32.99 kJ/mol.The results showed that the hydrogen bonding contribute to the interaction energies dominantly,The corresponding bonds stretching motions in all complexes are red-shifted relative to that of the monomer,which is in agreement with experimental results.

  4. Antioxidant Activity and α-Glucosidase Inhibitory Activities of the Polycondensate of Catechin with Glyoxylic Acid.

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    Sheng Geng

    Full Text Available In order to investigate polymeric flavonoids, the polycondensate of catechin with glyoxylic acid (PCG was prepared and its chemically antioxidant, cellular antioxidant (CAA and α-glucosidase inhibitory activities were evaluated. The DPPH and ABTS radical scavenging activities and antiproliferative effect of PCG were lower than those of catechin, while PCG had higher CAA activity than catechin. In addition, PCG had very high α-glucosidase inhibitory activities (IC50 value, 2.59 μg/mL in comparison to catechin (IC50 value, 239.27 μg/mL. Inhibition kinetics suggested that both PCG and catechin demonstrated a mixture of noncompetitive and anticompetitive inhibition. The enhanced CAA and α-glucosidase inhibitor activities of PCG could be due to catechin polymerization enhancing the binding capacity to the cellular membrane and enzymes.

  5. Kinetics and Mechanistic Studies on the Reaction between Cytochrome c and Tea Catechins

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    Lihua Wang

    2014-08-01

    Full Text Available Green tea is characterized by the presence of an abundance of polyphenolic compounds, also known as catechins, including epicatechin (EC, epigallocatechin (EGC, epicatechin gallate (EGC and epigallocatechin gallate (EGCG. In addition to being a popular beverage, tea consumption has been suggested as a mean of chemoprevention. However, its mode of action is unclear. It was discovered that tea catechins can react with cytochrome c. When oxidized cytochrome c was mixed with catechins commonly found in green tea under non-steady-state conditions, a reduction of cytochrome c was observed. The reaction rate of the catechins was dependent on the pH and the nature of the catechin. The pseudo-first order rate constant obtained increased in the order of EC < ECG < EGC < EGCG, which is consistent with previously reported superoxide reduction activities and Cu2+ reduction activities of tea catechins.

  6. Antioxidant Activity and α-Glucosidase Inhibitory Activities of the Polycondensate of Catechin with Glyoxylic Acid

    Science.gov (United States)

    Ma, Hanjun; Liu, Benguo

    2016-01-01

    In order to investigate polymeric flavonoids, the polycondensate of catechin with glyoxylic acid (PCG) was prepared and its chemically antioxidant, cellular antioxidant (CAA) and α-glucosidase inhibitory activities were evaluated. The DPPH and ABTS radical scavenging activities and antiproliferative effect of PCG were lower than those of catechin, while PCG had higher CAA activity than catechin. In addition, PCG had very high α-glucosidase inhibitory activities (IC50 value, 2.59 μg/mL) in comparison to catechin (IC50 value, 239.27 μg/mL). Inhibition kinetics suggested that both PCG and catechin demonstrated a mixture of noncompetitive and anticompetitive inhibition. The enhanced CAA and α-glucosidase inhibitor activities of PCG could be due to catechin polymerization enhancing the binding capacity to the cellular membrane and enzymes. PMID:26960205

  7. Study on the interaction of catechins with human serum albumin using spectroscopic and electrophoretic techniques

    Science.gov (United States)

    Trnková, Lucie; Boušová, Iva; Staňková, Veronika; Dršata, Jaroslav

    2011-01-01

    The interaction between eight naturally occurring flavanols (catechin, epicatechin, gallocatechin, epigallocatechin, catechin gallate, epicatechin gallate, gallocatechin gallate, and epigallocatechin gallate) and human serum albumin (HSA) has been investigated by spectroscopic (fluorescence quenching and UV-Vis absorption) and electrophoretic (native and SDS PAGE) techniques under simulated physiological conditions (pH 7.40, 37 °C). The spectroscopic results confirmed the complex formation for the tested systems. The binding constants and the number of binding sites were obtained by analysis of fluorescence data. The strongest binding affinity to HSA was found for epicatechin gallate and decreased in the order epicatechin gallate ⩾ catechin gallate > epigallocatechin gallate > gallocatechin gallate ≫ epicatechin ⩾ catechin > gallocatechin ⩾ epigallocatechin. All free energy changes possessed negative sign indicating the spontaneity of catechin-HSA systems formation. The binding distances between the donor (HSA) and the acceptors (catechins) estimated by the Förster theory revealed that non-radiation energy transfer from HSA to catechins occurred with high possibility. According to results obtained by native PAGE, the galloylated catechins increased the electrophoretic mobility of HSA, which indicated the change in the molecular charge of HSA, whilst the non-galloylated catechins caused no changes. The ability of aggregation and cross-linking of tested catechins with HSA was not proved by SDS-PAGE. The relationship between the structure characteristics of all tested catechins (e.g. presence of the galloyl moiety on the C-ring, the number of hydroxyl groups on the B-ring, and the spatial arrangement of the substituents on the C-ring) and their binding properties to HSA is discussed. The presented study contributes to the current knowledge in the area of protein-ligand binding, particularly catechin-HSA interactions.

  8. Stability of Green Tea Catechins in Commercial Tea Leaves during Storage for 6 Months

    Science.gov (United States)

    To help meet the needs of consumers, producers of dietary tea products, and researchers for information on health-promoting tea ingredients, we determined by HPLC seven catechins [(–)-epigallocatechin (EGC), (–)-catechin (C), (+)-epicatechin (EC), (–)-epigallocatechin 3-gallate (EGCG), (–)-gallocate...

  9. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation.

    Science.gov (United States)

    Clarke, Kayleigh A; Dew, Tristan P; Watson, Rachel E B; Farrar, Mark D; Osman, Joanne E; Nicolaou, Anna; Rhodes, Lesley E; Williamson, Gary

    2016-01-01

    Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin levels in the skin of healthy volunteers after consumption of green tea and how catechins in the plasma are related to their presence in skin tissue samples. In an open oral intervention study, 11 subjects consumed green tea and vitamin C supplements daily for 3months. Presupplementation and postsupplementation plasma samples, suction blister fluid and skin biopsies were collected; the latter two samples were collected both before and after UVR. A sensitive high-performance liquid chromatography/mass spectrometric assay was used to measure the intact catechin metabolites, conjugates and free forms. Seven green tea catechins and their corresponding metabolites were identified postsupplementation in skin biopsies, 20 in blister fluid and 26 in plasma, with 15 green tea catechin metabolites present in both blister fluid and plasma. The valerolactone, O-methyl-M4-O-sulfate, a gut microbiota metabolite of catechins, was significantly increased 1.6-fold by UVR in blister fluid samples. In conclusion, there were some common catechin metabolites in the plasma and blister fluid, and the concentration was always higher in plasma. The results suggest that green tea catechins and metabolites are bioavailable in skin and provide a novel link between catechin metabolites derived from the skin and gut microbiota. PMID:26454512

  10. Extraction of catechins and caffeine from different tealeaves and comparison with micellar electrokinetic chromatography

    Institute of Scientific and Technical Information of China (English)

    SONG Guanqun; LIN Jinming; Qu Feng; C.W.Huie

    2003-01-01

    This work describes the simultaneous deter- mination of catechins and caffeine in green, black tealeaves and canned tea-drink using micellar electrokinetic chromatography. The catechins analyzed include (+)-catechin, (-)- epicatechin, (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epigallocatechin gallate. Using UV absorption method at 280 nm, the limits of detections of catechins and caffeine are 10-6 mol/L, which is suitable for the real sample determination. Using this analytical method, the extraction of these compounds from the tealeaves with hot water is compared under different temperatures. The effects of temperature on the amount of catechins and caffeine extracted are evident, showing that (-)-epigallocatechin gallate is the most easiest to be extracted at 100℃. The stability of catechins and caffeine in stocking solution of tea-drink at 4℃ is also compared on five consecutive days. The contents of catechins and caffeine in green and black teas are discussed and the difference of the content between different tealeaves can provide a reference for the assessment of tea quality.

  11. Protective role of antioxidant vitamin E and catechin on idarubicin-induced cardiotoxicity in rats

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    Kalender S.

    2002-01-01

    Full Text Available Idarubicin is an anthracycline antibiotic extensively used in acute leukemia. In the present study we investigated whether vitamin E and catechin can reduce the toxic effects of idarubicin. Vitamin E (200 IU kg-1 week-1, catechin (200 mg kg-1 week-1, idarubicin (5 mg kg-1 week-1, idarubicin + vitamin E (200 IU kg-1 week-1, and idarubicin + catechin (200 mg kg-1 week-1 combinations were given to male Sprague-Dawley rats weighing 210 to 230 g (N = 6/group. Idarubicin-treated animals exhibited a decrease in body and heart weight, a decrease in myocardial contractility, and changes in ECG parameters (P<0.01. Catechin + idarubicin- and vitamin E + idarubicin-treated groups exhibited similar alterations, but changes were attenuated in comparison to those in cardiac muscle of idarubicin-treated rats (P<0.05. Superoxide dismutase and catalase activity was reduced in the idarubicin-treated group (P<0.05. Glutathione peroxidase levels were decreased in the idarubicin-treated group (P<0.05 and reached maximum concentrations in the catechin- and catechin + idarubicin-treated groups compared to control (P<0.01. Malondialdehyde activity was decreased in the catechin + idarubicin-treated groups compared to control and increased in the other groups, reaching maximum concentrations in the vitamin E-treated group (P<0.01. In electron microscopy studies, swelling of the mitochondria and dilatation of the sarcoplasmic reticulum of myocytes were observed in the idarubicin-treated groups. In groups that were given idarubicin + vitamin E and idarubicin + catechin, the only morphological change was a weak dilatation of the sarcoplasmic reticulum. We conclude that catechin and vitamin E significantly reduce idarubicin-induced cardiotoxicity in rats.

  12. PROCYANIDIN AND CATECHIN CONTENT AND ANTIOXIDANT CAPACITY OF COCOA AND CHOCOLATE PRODUCTS

    Science.gov (United States)

    Cocoa and chocolate products from major brands were analyzed blinded for total antioxidant capacity (AOC) (lipophilic and hydrophilic ORACFL), catechins, and procyanidins (monomer through polymers). Accuracy of analyses was ascertained by comparing analyses on a NIST standard reference chocolate wit...

  13. Protecting effect on gamma-ray damage of DNA by tea catechin

    International Nuclear Information System (INIS)

    The protecting effect of the tea catechin on the radiation induced scission of DNA in vitro. was examined. In addition, ESR spin-trapping method was used to make clear the mechanism of the protection. (author)

  14. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation

    OpenAIRE

    Clarke KA, Dew TP, Watson RE, Farrar MD, Osman JE, Nicolaou A, Rhodes LE, Williamson G

    2016-01-01

    Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin level...

  15. Quantification of the predominant monomeric catechins in baking chocolate standard reference material by LC/APCI-MS.

    Science.gov (United States)

    Nelson, Bryant C; Sharpless, Katherine E

    2003-01-29

    Catechins are polyphenolic plant compounds (flavonoids) that may offer significant health benefits to humans. These benefits stem largely from their anticarcinogenic, antioxidant, and antimutagenic properties. Recent epidemiological studies suggest that the consumption of flavonoid-containing foods is associated with reduced risk of cardiovascular disease. Chocolate is a natural cocoa bean-based product that reportedly contains high levels of monomeric, oligomeric, and polymeric catechins. We have applied solid-liquid extraction and liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometry to the identification and determination of the predominant monomeric catechins, (+)-catechin and (-)-epicatechin, in a baking chocolate Standard Reference Material (NIST Standard Reference Material 2384). (+)-Catechin and (-)-epicatechin are detected and quantified in chocolate extracts on the basis of selected-ion monitoring of their protonated [M + H](+) molecular ions. Tryptophan methyl ester is used as an internal standard. The developed method has the capacity to accurately quantify as little as 0.1 microg/mL (0.01 mg of catechin/g of chocolate) of either catechin in chocolate extracts, and the method has additionally been used to certify (+)-catechin and (-)-epicatechin levels in the baking chocolate Standard Reference Material. This is the first reported use of liquid chromatography/mass spectrometry for the quantitative determination of monomeric catechins in chocolate and the only report certifying monomeric catechin levels in a food-based Standard Reference Material. PMID:12537419

  16. Effects of different brewing conditions on catechin content and sensory acceptance in Turkish green tea infusions.

    Science.gov (United States)

    Saklar, Sena; Ertas, Erdal; Ozdemir, Ibrahim S; Karadeniz, Bulent

    2015-10-01

    The optimal brewing conditions for Turkish green tea were determined on the basis of extracted catechins and sensory attributes. Green tea infusions were prepared at 75, 85 and 95 °C with brewing times of 1, 2, 3, 5, 10, 20, 30 and 45 min. The amounts of epistructured catechins (EGCG, EGC, ECG, EC), non-epistructured catechins (C, GC, GCG) and caffeine in brewed tea samples were analysed. Sensory analyses were performed by nine trained panelists for infusion colour, taste, aroma and overall acceptability. Brewing at 85 °C for 3 min was found to be the optimal condition, where the EGCG content was at a maximum of 50.69 mg/100 ml with the highest sensory scores. It was observed that the yield of epistructured catechins increased rapidly for the first 3-5 min of brewing at 85 °C, and increased brewing time resulted in a decrease in the yield of epistructured catechins. The amount of nonepistructured catechins continued to increase with longer extraction times. Sensory scores for infusion colour, taste, aroma and overall acceptability were highest at 3 and 5 min brewing times at all temperatures. Sensory scores were very low for 30 and 45 min brewing at 85 and 95 °C due to the bitter taste and dark colour. PMID:26396411

  17. Synthesis of calixarenes and their extraction performance for ester catechins

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A series of extractants (tert-butylcalix[6]arene, tert-butylcalix[8]arene and octeacetate of tert-butylcalix[8]arene) were synthesized, and their structures were identified by IR and 1H-NMR. The distribution behavior of ester catechins monomer in the aqueous and chloroform two-phase system containing one of calixarene was studied. The influences of different extractants,concentration of tert-butylcalix[8]arene and extraction temperature on the partition coefficients and the separation factors were investigated. The experiment results show that tert-butylcalix[8]arene is the best extractant that forms a more stable supramolecular compound with gallocatechin gallate (GCG) than with epigallocathechin gallate (EGCG) or epicatechin gallate (ECG). When the concentration ofp-tert-butylcalix[8]arene is 3.79 mmol/L, the extraction temperature is 4 ℃C, the partition coefficients of KGG cG, KECG,KEGG cG are 0.987, 0.629, 0.449, the separation factors ofα1 and α2 are 1.450 and 1.596, respectively. The important factors influencing the extraction properties of calixarene are discovered to be its cavity size and hydrogen bonding.

  18. The behaviour of green tea catechins in a full-fat milk system under conditions mimicking the cheesemaking process.

    Science.gov (United States)

    Rashidinejad, Ali; Birch, E John; Everett, David W

    2016-09-01

    Due to their well-known health benefits, green tea catechins have received recent attention as natural additives in foods such as dairy products. However, they may present some irreversible associations with milk components (e.g. protein and milk fat globules). To investigate the behaviour of two important green tea catechins, (+)-catechin (C) and (-)-epigallocatechin gallate (EGCG), in a standard whole milk system under the conditions of cheesemaking, 250 and 500 ppm of each catechin were added to whole milk (3.3% fat). Although both C and EGCG at either concentration increased both total phenolic content and total antioxidant capacity of the subnatants obtained from the milk system, there was a less linear increase when the concentration of the catechins was doubled, whereas C or EGCG were recovered (measured by HPLC) differently. Overall, these results suggest a degree of associations between green tea catechins with milk proteins and milk fat. PMID:27282241

  19. Molecular interactions between green tea catechins and cheese fat studied by solid-state nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Rashidinejad, Ali; Birch, Edward J; Hindmarsh, Jason; Everett, David W

    2017-01-15

    Molecular integrations between green tea catechins and milk fat globules in a cheese matrix were investigated using solid-state magic angle spinning nuclear magnetic resonance spectroscopy. Full-fat cheeses were manufactured containing free catechin or free green tea extract (GTE), and liposomal encapsulated catechin or liposomal encapsulated GTE. Molecular mobility of the carbon species in the cheeses was measured by a wide-line separation technique. The (1)H evolution frequency profile of the (13)C peak at 16ppm obtained for the control cheese and cheeses containing encapsulated polyphenols (catechin or GTE) were similar, however, the spectrum was narrower for cheeses containing free polyphenols. Differences in spectral width indicates changes in the molecular mobility of --CH3- or -C-C-PO4- species through hydrophobic and/or cation-π associations between green tea catechins and cheese fat components. However, the similar spectral profile suggests that encapsulation protects cheese fat from interaction with catechins. PMID:27542471

  20. Effects of Catechins and Wheat Bran on the Beef Color in the Late Fattening Period of Hanwoo Steers

    OpenAIRE

    Kim, Do Hyung; Oh, Young Kyoon; Jang, Sun Sik; Kwon, Eung Gi; Seol, Yong Joo; Ok, Ji Un; Park, Keun Kyu; Lee, Sung Sill; Kim, Kyoung Hoon

    2012-01-01

    This study was conducted to evaluate the effects of dietary supplementation of catechins and wheat bran on growth performance, carcass characteristics and meat color using forty-eight Hanwoo steers. Each steer was randomly assigned to one of four treatments. Treatments were as follows: control, catechins, wheat bran, and catechins+wheat bran (CW). At the end of the feeding trial, blood samples were collected for analysis of hemoglobin and iron concentration, and then steers were slaughtered a...

  1. Cancer Therapy by Catechins Involves Redox Cycling of Copper Ions and Generation of Reactive Oxygen Species

    Directory of Open Access Journals (Sweden)

    Mohd Farhan

    2016-02-01

    Full Text Available Catechins, the dietary phytochemicals present in green tea and other beverages, are considered to be potent inducers of apoptosis and cytotoxicity to cancer cells. While it is believed that the antioxidant properties of catechins and related dietary agents may contribute to lowering the risk of cancer induction by impeding oxidative injury to DNA, these properties cannot account for apoptosis induction and chemotherapeutic observations. Catechin (C, epicatechin (EC, epigallocatechin (EGC and epigallocatechin-3-gallate (EGCG are the four major constituents of green tea. In this article, using human peripheral lymphocytes and comet assay, we show that C, EC, EGC and EGCG cause cellular DNA breakage and can alternatively switch to a prooxidant action in the presence of transition metals such as copper. The cellular DNA breakage was found to be significantly enhanced in the presence of copper ions. Catechins were found to be effective in providing protection against oxidative stress induced by tertbutylhydroperoxide, as measured by oxidative DNA breakage in lymphocytes. The prooxidant action of catechins involved production of hydroxyl radicals through redox recycling of copper ions. We also determined that catechins, particularly EGCG, inhibit proliferation of breast cancer cell line MDA-MB-231 leading to a prooxidant cell death. Since it is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies, cancer cells would be more subject to redox cycling between copper ions and catechins to generate reactive oxygen species (ROS responsible for DNA breakage. Such a copper dependent prooxidant cytotoxic mechanism better explains the anticancer activity and preferential cytotoxicity of dietary phytochemicals against cancer cells.

  2. The impact of microbial biotransformation of catechin in enhancing the allelopathic effects of Rhododendron formosanum.

    Science.gov (United States)

    Wang, Chao-Min; Li, Tsai-Chi; Jhan, Yun-Lian; Weng, Jen-Hsien; Chou, Chang-Hung

    2013-01-01

    Rhododendron formosanum is distributed widely in the central mountains in Taiwan and the major allelopathic compound in the leaves has been identified as (-)-catechin, which is also a major allelochemical of an invasive spotted knapweed in North America. Soil microorganisms play key roles in ecosystems and influence various important processes, including allelopathy. However, no microorganism has been identified as an allelochemical mediator. This study focused on the role of microorganisms in the allelopathic effects of R. formosanum. The microorganism population in the rhizosphere of R. formosanum was investigated and genetic analysis revealed that the predominant genera of microorganisms in the rhizosphere of R. formosanum were Pseudomonas, Herbaspirillum, and Burkholderia. The dominant genera Pseudomonas utilized (-)-catechin as the carbon source and catalyzed the conversion of (-)-catechin into protocatechuic acid in vitro. The concentrations of allelochemicals in the soil were quantified by liquid chromatography-electrospray ionization/tandem mass spectrometry. The concentration of (-)-catechin in the soil increased significantly during the extreme rainfall in the summer season and suppressed total bacterial populations. Protocatechuic acid accumulation was observed while total bacterial populations increased abundantly in both laboratory and field studies. Allelopathic interactions were tested by evaluating the effects of different allelochemicals on the seed germination, radicle growth, and photosynthesis system II of lettuce. Protocatechuic acid exhibited higher phytotoxicity than (-)-catechin did and the effect of (-)-catechin on the inhibition of seed germination was enhanced by combining it with protocatechuic acid at a low concentration. This study revealed the significance of the allelopathic interactions between R. formosanum and microorganisms in the rhizosphere. These findings demonstrate that knowledge regarding the precise biotransformation

  3. Catechin contents of foods commonly consumed in The Netherlands. 2. Tea, wine, fruit juices, and chocolate milk.

    Science.gov (United States)

    Arts, I C; van De Putte, B; Hollman, P C

    2000-05-01

    Catechins, compounds that belong to the flavonoid class, are potentially beneficial to human health. To enable an epidemiological evaluation of catechins, data on their contents in foods are required. HPLC with UV and fluorescence detection was used to determine the levels of (+)-catechin, (-)-epicatechin, (+)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg) in 8 types of black tea, 18 types of red and white wines, apple juice, grape juice, iced tea, beer, chocolate milk, and coffee. Tea infusions contained high levels of catechins (102-418 mg of total catechins/L), and tea was the only beverage that contained GC, EGC, ECg, and EGCg in addition to (+)-catechin and (-)-epicatechin. Catechin concentrations were still substantial in red wine (27-96 mg/L), but low to negligible amounts were found in white wine, commercially available fruit juices, iced tea, and chocolate milk. Catechins were absent from beer and coffee. The data reported here provide a base for the epidemiological evaluation of the effect of catechins on the risk for chronic diseases. PMID:10820090

  4. (--Catechin in Cocoa and Chocolate: Occurence and Analysis of an Atypical Flavan-3-ol Enantiomer

    Directory of Open Access Journals (Sweden)

    Rudolf Galensa

    2007-07-01

    Full Text Available Cocoa contains high levels of different flavonoids. In the present study, the enantioseparation of catechin and epicatechin in cocoa and cocoa products by chiral capillary electrophoresis (CCE was performed. A baseline separation of the catechin and epicatechin enantiomers was achieved by using 0.1 mol·L−1 borate buffer (pH 8.5 with 12 mmol·L-1 (2-hydroxypropyl-γ-cyclodextrin as chiral selector, a fused-silica capillary with 50 cm effective length (75 μm I.D., +18 kV applied voltage, a temperature of 20°C and direct UV detection at 280 nm. To avoid comigration or coelution of other similar substances, the flavan-3-ols were isolated and purified using polyamide-solid-phase-extraction and LC-MS analysis. As expected, we found (--epicatechin and (+-catechin inunfermented, dried, unroasted cocoa beans. In contrast, roasted cocoa beans and cocoa products additionally contained the atypical flavan-3-ol (--catechin. This is generally formed during the manufacturing process by an epimerization which converts (--epicatechin to its epimer (--catechin. High temperatures during the cocoa bean roasting process and particularly the alkalization of the cocoa powder are the main factors inducing the epimerization reaction. In addition to the analysis of cocoa and cocoa products, peak ratios were calculated for a better differentiation of the cocoa products.

  5. Comparison of Some Extraction Methods for Isolation of Catechins and Caffeine from Turkish Green Tea

    Directory of Open Access Journals (Sweden)

    Ezgi DEMİR

    2015-07-01

    Full Text Available Effective extraction of anticancer and antioxidant principles from Turkish green tea were main purpose of this work. The pre-optimized experimental condition for liquid extraction was employed for comparative appraisal.  Not only extraction methods also nature of the green tea samples (fresh, dried or frozen and quantitative yields related to collection periods were investigated.  After extraction of the green tea with various techniques the extract was partitioned with chloroform to remove caffeine, after that the extract was partitioned with ethyl acetate to obtain catechin mixture. Quantification of individual catechins was carried out by HPLC and analysis results proved that epigallocatechin gallate (EGCG was main catechin specie present in all extracts. The results indicate that hot water extraction (at 80 0C provides higher catechin yield when compared to other methods. The highest extract yields were obtained with dried leaves collected in second collection period. The crude catechin mixture contains high amount of EGCG and might be used as raw material for production of plant remedies at industrial scale.

  6. Interactions between tea catechins and casein micelles and their impact on renneting functionality.

    Science.gov (United States)

    Haratifar, Sanaz; Corredig, Milena

    2014-01-15

    Many studies have shown that tea catechins bind to milk proteins. This research focused on the association of tea polyphenols with casein micelles, and the consequences of the interactions on the renneting behaviour of skim milk. It was hypothesized that epigallocatechin-gallate (EGCG), the main catechin present in green tea, forms complexes with the casein micelles and that the association modifies the processing functionality of casein micelles. The binding of EGCG to casein micelles was quantified using HPLC. The formation of catechin-casein micelles complexes affected the rennet induced gelation of milk, and the effect was concentration dependent. Both the primary as well as the secondary stage of gelation were affected. These experiments clearly identify the need for a better understanding of the effect of tea polyphenols on the processing functionality of casein micelles, before milk products can be used as an appropriate platform for delivery of bioactive compounds. PMID:24054208

  7. New Approaches for Effective Microwave Assisted Extraction of Caffeine and Catechins from Green Tea

    Directory of Open Access Journals (Sweden)

    Gönül SERDAR

    2016-01-01

    Full Text Available This study was designed to develop an effective microwave assisted extraction (MAE method for extraction of caffeine and catechins from green tea samples. A series of solvents (water, ethanol:water mixture or citric acid:water mixture were used for extraction of green tea samples (fresh, frozen or dried collected in three collection periods (first, second and third collection periods. Tea samples were extracted using water in a close microwave system under the certain extraction conditions. Extraction was carried out under a controlled 600 W microwave power at 80 oC temperature for 4 min irradiation time. Alternative to water, an ethanol-water mixture (1:1 or a citric acid-water (1:1 mixture was used as extracting solvent under the same conditions. After MAE crude aqueous extract was partitioned first with chloroform to separate caffeine then ethyl acetate for catechins.  Both caffeine and catechin extraction was quite successful with microwave assisted system employing only 4 minutes treatment. The highest caffeine yield was obtained in the second collection period using frozen green tea samples and ethanol-water as extracting solvent. The yield of catechin extracts was between 0.84-3.96% depending on the solvent system used for extraction. Ethanol-water mixture seems to be appropriate for effective extraction in the basis of extract yields. However, HPLC results showed that individual catechin content of each extraction is more important criteria for the evaluation of most effective extraction medium rather than the mass of the extract.  Using citric acid as extracting solvent in MAE seem to be more fruitful providing 100% catechin mixture with the highest EGCG content. 

  8. Location and Effects of an Antitumoral Catechin on the Structural Properties of Phosphatidylethanolamine Membranes

    Directory of Open Access Journals (Sweden)

    Francisco Casado

    2016-06-01

    Full Text Available Green tea catechins exhibit high diversity of biological effects including antioncogenic properties, and there is enormous interest in their potential use in the treatment of a number of pathologies. It is recognized that the mechanism underlying the activity of catechins relay in part in processes related to the membrane, and many studies revealed that the ability of catechins to interact with lipids plays a probably necessary role in their mechanism of action. We present in this work the characterization of the interaction between an antitumoral synthetically modified catechin (3-O-(3,4,5-trimethoxybenzoyl-(−-catechin, TMCG and dimiristoylphosphatidyl-ethanolamine (DMPE membranes using an array of biophysical techniques which include differential scanning calorimetry, X-ray diffraction, infrared spectroscopy, atomic force microscopy, and molecular dynamics simulations. We found that TMCG incorporate into DMPE bilayers perturbing the thermotropic transition from the gel to the fluid state forming enriched domains which separated into different gel phases. TMCG does not influence the overall bilayer assembly of phosphatidylethanolamine systems but it manages to influence the interfacial region of the membrane and slightly decrease the interlamellar repeat distance of the bilayer. TMCG seems to be located in the interior of the phosphatidylethanolamine bilayer with the methoxy groups being in the deepest position and some portion of the molecule interacting with the water interface. We believe that the reported interactions are significant not only from the point of view of the known antitumoral effect of TMCG, but also might contribute to understanding the basic molecular mechanism of the biological effects of the catechins found at the membrane level.

  9. Location and Effects of an Antitumoral Catechin on the Structural Properties of Phosphatidylethanolamine Membranes.

    Science.gov (United States)

    Casado, Francisco; Teruel, José A; Casado, Santiago; Ortiz, Antonio; Rodríguez-López, José N; Aranda, Francisco J

    2016-01-01

    Green tea catechins exhibit high diversity of biological effects including antioncogenic properties, and there is enormous interest in their potential use in the treatment of a number of pathologies. It is recognized that the mechanism underlying the activity of catechins relay in part in processes related to the membrane, and many studies revealed that the ability of catechins to interact with lipids plays a probably necessary role in their mechanism of action. We present in this work the characterization of the interaction between an antitumoral synthetically modified catechin (3-O-(3,4,5-trimethoxybenzoyl)-(-)-catechin, TMCG) and dimiristoylphosphatidyl-ethanolamine (DMPE) membranes using an array of biophysical techniques which include differential scanning calorimetry, X-ray diffraction, infrared spectroscopy, atomic force microscopy, and molecular dynamics simulations. We found that TMCG incorporate into DMPE bilayers perturbing the thermotropic transition from the gel to the fluid state forming enriched domains which separated into different gel phases. TMCG does not influence the overall bilayer assembly of phosphatidylethanolamine systems but it manages to influence the interfacial region of the membrane and slightly decrease the interlamellar repeat distance of the bilayer. TMCG seems to be located in the interior of the phosphatidylethanolamine bilayer with the methoxy groups being in the deepest position and some portion of the molecule interacting with the water interface. We believe that the reported interactions are significant not only from the point of view of the known antitumoral effect of TMCG, but also might contribute to understanding the basic molecular mechanism of the biological effects of the catechins found at the membrane level. PMID:27347914

  10. Improvement of catechin production in Escherichia coli through combinatorial metabolic engineering.

    Science.gov (United States)

    Zhao, Shujuan; Jones, J Andrew; Lachance, Daniel M; Bhan, Namita; Khalidi, Omar; Venkataraman, Sylesh; Wang, Zhengtao; Koffas, Mattheos A G

    2015-03-01

    Reconstruction of highly efficient biosynthesis pathways is essential for the production of valuable plant secondary metabolites in recombinant microorganisms. In order to improve the titer of green tea catechins in Escherichia coli, combinatorial strategies were employed using the ePathBrick vectors to express the committed catechin pathway: flavanone 3β-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), and leucoanthocyanidin reductase (LAR). Three F3H, three DFR, and two LAR genes originating from different plant species were selected and synthesized, to create 18 pathway variants to be screened in E. coli. Constructs containing F3H(syn) originally from Camellia sinensis, DFR(syn) from Anthurium andraeanum, C. sinensis, or Fragaria ananass, and LAR(syn) from Desmodium uncinatum (p148, p158 and p168) demonstrated high conversion efficiency with either eriodictyol or naringenin as substrate. A highly efficient construct was created by assembling additional copies of DFR(syn) and LAR(syn) enabling a titer of 374.6 ± 43.6 mg/L of (+)-catechin. Improving the NADPH availability via the ΔpgiΔppc mutation, BLΔpgiΔppc-p148 produced the highest titer of catechin at 760.9 ± 84.3 mg/L. After utilizing a library of scaffolding proteins, the strain BLΔpgiΔppc-p168-759 reached the highest titer of (+)-catechin of 910.9 ± 61.3 mg/L from 1.0 g/L of eriodictyol in batch culture with M9 minimal media. The impact of oxygen availability on the biosynthesis of catechin was also investigated. PMID:25527438

  11. The effects of catechin rich teas and caffeine on energy expenditure and fat oxidation: a meta-analysis

    Science.gov (United States)

    Different outcomes of the effect of catechin-caffeine mixtures and caffeine-only supplementation on energy expenditure and fat oxidation have been reported in short-term studies. Therefore, a meta-analysis was conducted to elucidate whether catechin-caffeine mixtures and caffeine-only supplementatio...

  12. Beta-cyclodextrin/surface plasmon resonance detection system for sensing bitter-astringent taste intensity of green tea catechins.

    Science.gov (United States)

    Hayashi, Nobuyuki; Chen, Ronggang; Hiraoka, Masamitsu; Ujihara, Tomomi; Ikezaki, Hidekazu

    2010-07-28

    To develop a methodology for creating a sensor with a receptor for specific taste substances, we focused on constructing a sensing system for the bitter-astringent taste intensity of green tea catechins: (-)-epigallocatechin-3-O-gallate (EGCg), (-)-epicatechin-3-O-gallate (ECg), (-)-epigallocatechin (EGC), and (-)-epicatechin (EC). (1)H NMR titration experiments revealed that beta-cyclodextrin was an adequate receptor for sensing the bitter-astringent taste intensity of catechins. A surface plasmon resonance (SPR) system immobilized beta-cyclodextrin indicated larger responses for the gallate-type catechins in comparison to the non-gallate-type catechins. These responses corresponded to the tendency of the bitter-astringent taste intensity of the catechins felt by humans. Furthermore, the SPR system detected the larger stability of the complex between the gallate-type catechins and beta-cyclodextrin, which was interpreted as the aftertaste produced in humans by the gallate-type catechins. These results demonstrate that the beta-cyclodextrin/SPR system can sense the bitter-astringent taste intensity of the green tea catechins similar to human gustation. The methodology presented in this study can be used as a basic strategy for developing taste sensors with specific receptor functions. PMID:20572674

  13. Dynamic Ultrasound-Assisted Extraction of Catechins and Caffeine in Some Tea Samples

    International Nuclear Information System (INIS)

    A novel dynamic ultrasound-assisted extraction (DUAE) device has been constructed for extraction of five catechins and caffeine in solid sample. The accurate, simple, reproducible and sensitive method for the determination of five catechins and caffeine has been developed and validated. A comparison has been made of the efficiencies by employing DUAE and conventionally static ultrasound-assisted extraction (UAE). The proposed method can not only improve extraction efficiency but also decrease time and solvent consumption. The commercial Chinese tea samples, involving green and black teas, are rapidly analyzed by the proposed DUAE method. The linearity, range, selectivity, precision, accuracy, and robustness also showed acceptable values

  14. Chromatographic separation and concentration of quercetin and (+)-catechin using mesoporous composites based on MCM-41

    Science.gov (United States)

    Karpov, S. I.; Belanova, N. A.; Korabel'nikova, E. O.; Nedosekina, I. V.; Roessner, F.; Selemenev, V. F.

    2015-05-01

    Data on chromatographic separation of quercetin and (+)-catechin-flavonoids with similar physicochemical (including sorption) properties—are presented. The highest efficiency of chromatographic process at high sorption capacity of the material with respect to quercetin and slightly lower capacity for (+)-catechin were observed when silylated composites of ordered MCM-41 type materials were used. The application of acetonitrile as a solvent increased the sorption capacity of the material and can be recommended for separation of related polyphenol substances and their determination using ordered MCM-41 modified with trimethylchlorosilane as a stationary phase in a chromatographic column.

  15. Influence of catechins on bystander responses in CHO cells induced by alpha-particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Law, Y.L.; Wong, T.P.W. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Yu, K.N. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)], E-mail: peter.yu@cityu.edu.hk

    2010-04-15

    In this work, we studied alpha-particle induced and medium-mediated bystander effects in Chinese hamster ovary (CHO) cells through micronucleus (MN) assay. We showed that signal transduction from irradiated cells to bystander cells occur within a short time after irradiation. We then studied the effects of ROS (reactive oxygen species)-scavenging catechins in the medium before irradiation. We observed decreases in the percentage of bystander cells with MN formation and thus proved the protection effect of catechins on bystander cells from radiation.

  16. (-)-Catechin in Cocoa and Chocolate: Occurence and Analysis of an Atypical Flavan-3-ol Enantiomer

    OpenAIRE

    Rudolf Galensa; Menelaos Papagiannopoulos; Michael Kofink

    2007-01-01

    Cocoa contains high levels of different flavonoids. In the present study, the enantioseparation of catechin and epicatechin in cocoa and cocoa products by chiral capillary electrophoresis (CCE) was performed. A baseline separation of the catechin and epicatechin enantiomers was achieved by using 0.1 mol·L−1 borate buffer (pH 8.5) with 12 mmol·L-1 (2-hydroxypropyl)-γ-cyclodextrin as chiral selector, a fused-silica capillary with 50 cm effective length (75 μm I.D.), +18 kV appl...

  17. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation☆☆☆★

    Science.gov (United States)

    Clarke, Kayleigh A.; Dew, Tristan P.; Watson, Rachel E.B.; Farrar, Mark D.; Osman, Joanne E.; Nicolaou, Anna; Rhodes, Lesley E.; Williamson, Gary

    2016-01-01

    Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin levels in the skin of healthy volunteers after consumption of green tea and how catechins in the plasma are related to their presence in skin tissue samples. In an open oral intervention study, 11 subjects consumed green tea and vitamin C supplements daily for 3 months. Presupplementation and postsupplementation plasma samples, suction blister fluid and skin biopsies were collected; the latter two samples were collected both before and after UVR. A sensitive high-performance liquid chromatography/mass spectrometric assay was used to measure the intact catechin metabolites, conjugates and free forms. Seven green tea catechins and their corresponding metabolites were identified postsupplementation in skin biopsies, 20 in blister fluid and 26 in plasma, with 15 green tea catechin metabolites present in both blister fluid and plasma. The valerolactone, O-methyl-M4-O-sulfate, a gut microbiota metabolite of catechins, was significantly increased 1.6-fold by UVR in blister fluid samples. In conclusion, there were some common catechin metabolites in the plasma and blister fluid, and the concentration was always higher in plasma. The results suggest that green tea catechins and metabolites are bioavailable in skin and provide a novel link between catechin metabolites derived from the skin and gut microbiota. PMID:26454512

  18. Green Tea Catechin Consumption Enhances Exercise-Induced Abdominal Fat Loss

    Science.gov (United States)

    Aim: This study evaluated the influence of a green tea catechin beverage on body composition and fat distribution in overweight and obese adults during exercised-induced weight loss. Methods: Participants (N=132) were randomly assigned to receive a 500 mL beverage containing approximately 625 mg of...

  19. Molecular Dynamics Study on the Biophysical Interactions of Seven Green Tea Catechins with Cell Membranes

    Science.gov (United States)

    Molecular dynamics simulations were performed to study the interactions of bioactive catechins (flavonoids) commonly found in green tea with lipid bilayers, as model for cell membranes. Previously, a number of experimental studies rationalized catechin’s anticarcinogenic, antibacterial, and other be...

  20. Nutraceuticals for body-weight management: The role of green tea catechins.

    Science.gov (United States)

    Janssens, Pilou L H R; Hursel, Rick; Westerterp-Plantenga, Margriet S

    2016-08-01

    Green tea catechins mixed with caffeine have been proposed as adjuvants for maintaining or enhancing energy expenditure and for increasing fat oxidation, in the context of prevention and treatment of obesity. These catechins-caffeine mixtures seem to counteract the decrease in metabolic rate that occurs during weight loss. Their effects are of particular importance during weight maintenance after weight loss. Other metabolic targets may be fat absorption and the gut microbiota composition, but these effects still need further investigation in combination with weight loss. Limitations for the effects of green tea catechins are moderating factors such as genetic predisposition related to COMT-activity, habitual caffeine intake, and ingestion combined with dietary protein. In conclusion, a mixture of green tea catechins and caffeine has a beneficial effect on body-weight management, especially by sustained energy expenditure, fat oxidation, and preservation of fat free body-mass, after energy restriction induced body-weight loss, when taking the limitations into account. PMID:26836279

  1. Isolation and Purification of a Novel Long-chain Acyl Catechin from Lipophilic Tea Polyphenols

    Institute of Scientific and Technical Information of China (English)

    陈平; 杜琪珍

    2003-01-01

    Llpophilic tea polyphenols (LTP) was prepared by esterification of green tea polyphenols (GTP) with hexadecanoyl chloride. A novel long-chaln acyl catechin was isolated and purified from LTP by high-speed countercurrent chromatography (HSCCC).Its molecular structure was elucidated as epigallocatechin-3-O-gallate-4'-O-hexadecanate by elemental analysis, IR, MS and 1H NMR spectra.

  2. Antimicrobial activities of tea catechins and theaflavins and tea extracts against Bacillus cereus

    Science.gov (United States)

    We evaluated the antimicrobial activities of seven green tea catechins and four black tea theaflavins, generally referred to as flavonoids, as well as the aqueous extracts (infusions) of 36 commercial black, green, oolong, white, and herbal teas against Bacillus cereus (strain RM3190) incubated at 2...

  3. Content Variation of Catechin Markers, Total Phenolics and Caffeine in Green Tea Dietary Supplements.

    Science.gov (United States)

    Abourashed, Ehab A; Roberson, Cindy Leslie A; Elsharkawy, Nancy

    2016-01-01

    Green tea (Camellia sinensis) preparations are among the top selling products in the United States dietary supplements market. Numerous manufacturers claim different levels of specific catechin markers in their products while many others use total phenolic concentration instead, or not at all. Limited quality control results have been published for green tea dietary supplements over the past seven years. Thus, the goal of this work was to correlate determined levels of phenolics, catechins, and caffeine with manufacturer label claims for selected dietary supplement products (26 total) purchased in the United States. The Folin-Ciocalteu (FC) method was used to determine the total phenolic content while reversed-phase (RP) HPLC was used to quantify the major catechins: epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG). The developed HPLC method was validated for accuracy and precision. It utilized a C8 column with gradient elution of acetonitrile in 0.1% aqueous formic acid over 11 min total run time. Peak detection was performed at 280 nm. Caffeine was also included in the HPLC method as another non-phenolic alkaloid marker commonly found in green tea. Both methods showed a good correlation between the content of catechins and polyphenolic compounds in the selected products. The ranges of total catechins and polyphenol concentrations were 3.8-70.2% and 3.6-95.8%, respectively, while that of caffeine was 0.8-11.2%. The selected products displayed a wide range of marker levels. A lack of conformity in disclosing the actual levels of marker compounds was also noticed in the labeling of many products. PMID:25299974

  4. Estimating catechin concentrations of new shoots in the green tea field using ground-based hyperspectral image

    Science.gov (United States)

    Ryu, C. S.; Suguri, M.; Park, S. B.; Mikio, M.

    2013-10-01

    Hyperspectral camera was applied to establish the models of catechin concentration for green tea. The possibility of improvement for the models was checked by the multi-year models and the mutual prediction. ECg, EGCg and the ester catechin (ECg and EGCg) decreased with the growth but EC, EGC and the free catechin (EC and EGC) were changed by the covering. In partial least square regression (PLSR) models for each catechin, R2 (Relative Error for validation) was more than 0.785 (13.4%) for a single year data, 0.723 (13.3%) for two years data, and 0.756 (13.6%) for three years data except several catechins. It was possible to improve the precision and accuracy of models using the combination of catechin (free and ester type) or the combination of multi-year data. When each and each type of catechin model was predicted by the other year data, the accuracy of two years model improved comparing with it of a single year data. It means that the multi-year models might be more accurate than a single year models to predict the unknown data.

  5. Green Tea Catechin Metabolites Exert Immunoregulatory Effects on CD4(+) T Cell and Natural Killer Cell Activities.

    Science.gov (United States)

    Kim, Yoon Hee; Won, Yeong-Seon; Yang, Xue; Kumazoe, Motofumi; Yamashita, Shuya; Hara, Aya; Takagaki, Akiko; Goto, Keiichi; Nanjo, Fumio; Tachibana, Hirofumi

    2016-05-11

    Tea catechins, such as (-)-epigallocatechin-3-O-gallate (EGCG), have been shown to effectively enhance immune activity and prevent cancer, although the underlying mechanism is unclear. Green tea catechins are instead converted to catechin metabolites in the intestine. Here, we show that these green tea catechin metabolites enhance CD4(+) T cell activity as well as natural killer (NK) cell activity. Our data suggest that the absence of a 4'-hydroxyl on this phenyl group (B ring) is important for the effect on immune activity. In particular, 5-(3',5'-dihydroxyphenyl)-γ-valerolactone (EGC-M5), a major metabolite of EGCG, not only increased the activity of CD4(+) T cells but also enhanced the cytotoxic activity of NK cells in vivo. These data suggest that EGC-M5 might show immunostimulatory activity. PMID:27112424

  6. Effect of moderate intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions

    DEFF Research Database (Denmark)

    Gregersen, N.T.; Bitz, C.; Krog-Mikkelsen, I.;

    2009-01-01

    Green tea may stimulate energy metabolism; however, it is unclear if acute effects are caused by specific catechins, caffeine or their combination. The objective of the present study was to examine the separate and combined effects of different catechins and caffeine on energy expenditure (EE) and...... fat oxidation over a single day. Fifteen healthy, normal-weight males received capsules containing placebo, caffeine alone (150mg), or caffeine plus a catechin mixture (600 mg) enriched in either epigallocatechin-3-gallate (EGCG), epigallocatechin or a mix of catechins, in a randomised cross......-over double-blinded design. On each test day EE, respiratory quotient (RQ) and substrate oxidation were measured under sedentary conditions in a respiratory chamber for 13.5h. We found no significant treatment effect on EE (P=0.20) or RQ (P=0.68). EGCG with caffeine insignificantly raised EE and fat oxidation...

  7. Study of influence of catechins on bystander responses in alpha-particle radiobiological experiments using thin PADC films

    Energy Technology Data Exchange (ETDEWEB)

    Law, Y.L. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Yu, K.N., E-mail: peter.yu@cityu.edu.h [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)

    2009-10-15

    In this study, Chinese hamster ovary (CHO) cells were cultured in custom-made petri dishes with thin PADC films as substrates. Alpha particles with energies of 5 MeV were then irradiated from the bottom of PADC films. The DNA strand breaks in the bystander cells induced by irradiation were quantified with the use of terminal dUTP transferase-mediated nick end-labeling (TUNEL) assay. To study the influence of catechins on the bystander responses, catechins were added into the medium before alpha-particle irradiation of the cells. Fewer DNA strand breaks in the bystander cells were observed. As catechins are ROS (reactive oxygen species)-scavengers, the studied bystander cells might have been protected from radiation through scavenging of ROS by catechins.

  8. Allelopathic potential of catechins of the Tachigali myrmecophyla (Leguminosae); Potencial alelopatico de catequinas de Tachigali myrmecophyla (leguminosae)

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, Livia T.; Castro, Kelly Christina Ferreira; Arruda, Mara Silvia P.; Silva, Milton N. da; Arruda, Alberto C.; Mueller, Adolfo Henrique; Arruda, Giselle Maria Skelding P.; Santos, Alberdan Silva [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Centro de Ciencias Exatas e Naturais. Dept. de Quimica]. E-mail: livia_lobo@yahoo.com.br; Souza Filho, Antonio Pedro da Silva [EMBRAPA Amazonia Oriental, Belem, PA (Brazil). Lab. de Agroindustria

    2008-07-01

    Two compounds, (+)-catechin and epicatechin, were isolated from leaves of T. myrmecophyla, using chromatographic techniques. The structural identification was carried out on the basis of {sup 1}H and {sup 13}C NMR spectral data and comparison with literature data. The compounds (+)-catechin and epicatechin were submitted to germination inhibition and radicle and hypocotyl growth assays. Results showed some significant activities confirming the initial hypothesis about allelopathic properties of that plant. (author)

  9. Effect of catechins and tannins on depleted uranium-induced DNA strand breaks

    International Nuclear Information System (INIS)

    The effects of polyphenols on plasmid DNA strand breaks by depleted uranium were studied using four catechins: (+)-catechin, (-)-epicatechin, (-)-epigallocatechin (EGC), and (-)-epigallocatechin gallate (EGCG); seven tannins: Chinese gallotannin, persimmon tannin (PST), mimosa tannin (MMT), myrobalan tannin, quebracho tannin, gambir tannin, and chestnut tannin; and gallic acid. The plasmid DNA strand breaks by uranyl ion (UO22+) with hydrogen peroxide (H2O2) were strongly enhanced by EGC, EGCG, MMT, and PST (condenced tannins). The obtained results showed that the DNA strand breaks are caused by UO22+ through the direct interaction between the uranyl complex and the negatively charged DNA phosphate backbone. The additional DNA strand breaks by the addition of polyphenols occurred through an indirect process by the reduction of UO22+ to UO2+ and hydroxyl radical formation through a Fenton-type reaction with H2O2. (author)

  10. Study of Caffein - Catechin Association in Lyophilized Fresh Seeds and in Stabilized Extract of Cola nitida.

    Science.gov (United States)

    Maillard, C; Babadjamian, A; Balansard, G; Ollivier, B; Bamba, D

    1985-12-01

    Caffein-catechin association has been demonstrated in lyophilized fresh seeds and in stabilized extract of COLA NITIDA (Vent.) A. Chev. by using various analytical techniques which have made it possible to determine specifically the concentrations of free caffein versus associated caffein. Associated caffein varies from 0% in dried seeds to 91% in lyophilized fresh seeds and in stabilized extract of COLA. It was possible to simulate these quantitative variations of associated caffein by using an experimental model with a saturated aqueous solution of caffein and various amounts of catechin. Infrared spectrophotometric studies have shown the hydrogen bond type of the association. The differences of pharmacological effects of fresh and dried seeds may be due to the varying concentrations of associated and free caffein. PMID:17345274

  11. Use of cyclodextrins to recover catechin and epicatechin from red grape pomace.

    Science.gov (United States)

    López-Miranda, Santiago; Serrano-Martínez, Ana; Hernández-Sánchez, Pilar; Guardiola, Lucía; Pérez-Sánchez, Horacio; Fortea, Isabel; Gabaldón, José Antonio; Núñez-Delicado, Estrella

    2016-07-15

    The capacity of cyclodextrins (CDs) to extract phenolic compounds from grape pomace was evaluated and compared with that of ethanol/water or aqueous extraction. The extraction method (stirring and ultrasound), temperature and time were also studied. Total phenolic compounds (TPC) and antioxidant activity were measured, and HPLC analysis was used to identify the phenolic compounds. The extracts obtained using the ethanol/water mixture presented the highest TPC content and antioxidant activity, followed by those obtained using CD solutions. The addition of CDs to the extractant agent had a selective effect on the extraction of catechin and epicatechin. The yield of catechin and epicatechin by using aqueous solutions of CDs was similar to that obtained using organic solvents as ethanol. PMID:26948628

  12. Green tea catechins are potent anti-oxidants that ameliorate sodium iodate-induced retinal degeneration in rats.

    Science.gov (United States)

    Yang, Yaping; Qin, Yong Jie; Yip, Yolanda W Y; Chan, Kwok Ping; Chu, Kai On; Chu, Wai Kit; Ng, Tsz Kin; Pang, Chi Pui; Chan, Sun On

    2016-01-01

    Green tea extracts exhibit anti-oxidative and anti-inflammatory actions in different disease conditions. We hypothesized that green tea extract and its catechin constituents ameliorate sodium iodate-induced retinal degeneration in rats by counteracting oxidative stress. In this study, adult Sprague-Dawley rats were intravenously injected with a single dose of sodium iodate. Green tea extract (GTE; Theaphenon-E) or combinations of its catechin constituents, including (-)-epigallocatechin gallate (EGCG), were administered intra-gastrically before injection. Live imaging analysis using confocal scanning laser ophthalmoscopy and spectral-domain optical coherence tomography showed a progressive increase of degenerating profile across the retinal surface and decrease in thickness of outer nuclear layer (ONL) at Day-14 of post-injection. These lesions were significantly ameliorated by Theaphenon-E and catechin combinations with EGCG. Catechins with exclusion of EGCG did not show obvious protective effect. Histological analyses confirmed that Theaphenon-E and catechins containing EGCG protect the retina by reducing ONL disruption. Retinal protective effects were associated with reduced expression of superoxide dismutase, glutathione peroxidase and caspase-3, and suppression of 8-iso-Prostaglandin F2α generation in the retina. In summary, GTE and its catechin constituents are potent anti-oxidants that offer neuroprotection to the outer retinal degeneration after sodium iodate insult, among which EGCG is the most active constituent. PMID:27383468

  13. Encapsulation of catechin and epicatechin on BSA NPS improved their stability and antioxidant potential

    OpenAIRE

    Ramdhan, Yadav; Kumar, Dharmesh; Kumari, Avnesh; Sudesh Kumar, Yadav

    2014-01-01

    Nanoencapsulation of antioxidant molecules on protein nanoparticles (NPs) could be an advanced approach for providing stable, better food nutraceuticals and anticancer drugs. The bioavailability and stability of catechin (CAT) and epicatechin (ECAT) were very poor. In the present study, the CAT and ECAT were loaded on bovine serum albumin (BSA) NPs following desolvation method. The transmission electron microscope (TEM) and atomic force microscope (AFM) recorded size of CAT-BSA NPs and ECAT-B...

  14. Measurement of Antioxidant Activity of Wine Catechins, Procyanidins, Anthocyanins and Pyranoanthocyanins

    OpenAIRE

    Julián C. Rivas-Gonzalo; Milan ŽemliÄÂka; María P. Martín-López; María García-Alonso; Jan Muselík

    2007-01-01

    Nowadays, there is considerable interest in finding out about antioxidants that are consumed in the habitual diet. It is known that polyphenols are involved in reducing the risk of diseases associated with oxidative stress. The in vitro antioxidant activity of the principal wine polyphenolic compounds (catechins, procyanidins, anthocyanins and pyranoanthocyanins) was studied in this work. Four distinct methods were used to assess the antioxidant capacity of the tested compounds: inhibition of...

  15. The Impact of Microbial Biotransformation of Catechin in Enhancing the Allelopathic Effects of Rhododendron formosanum

    OpenAIRE

    Wang, Chao-Min; Li, Tsai-Chi; Jhan, Yun-Lian; Weng, Jen-Hsien; Chou, Chang-Hung

    2013-01-01

    Rhododendron formosanum is distributed widely in the central mountains in Taiwan and the major allelopathic compound in the leaves has been identified as (-)-catechin, which is also a major allelochemical of an invasive spotted knapweed in North America. Soil microorganisms play key roles in ecosystems and influence various important processes, including allelopathy. However, no microorganism has been identified as an allelochemical mediator. This study focused on the role of microorganisms i...

  16. The case against (-)-catechin involvement in allelopathy of Centaurea stoebe (spotted knapweed)

    OpenAIRE

    Duke, Stephen O; Franck E. Dayan; Bajsa, Joanna; Meepagala, Kumudini M; Hufbauer, Ruth A; Blair, Amy C

    2009-01-01

    Proving allelopathic chemical interference is a daunting endeavor, in that production and movement of a phytotoxin from a donor plant to a receiving plant must be demonstrated in the substrate in which the plants grow, which is usually a complex soil matrix. The soil levels or soil flux levels of the compound generated by the donor must be proven to be sufficient to adversely affect the receiving plant. Reports of (-)-catechin to be the novel weapon used by Centaurea stoebe (spotted knapweed)...

  17. Quantitative analysis of catechins in Saraca asoca and correlation with antimicrobial activity

    Institute of Scientific and Technical Information of China (English)

    Amey Shirolkar; Anjum Gahlaut; Anil K. Chhillar; Rajesh Dabur

    2013-01-01

    Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal formulations. In present study, efforts have been made to explore antimicrobial activity and its co-relation with the distributions of catechins in the organs of S. asoca using targeted MS/MS. Eight extracts (cold and hot water) from four different organs of S. asoca and two drugs were prepared and antimicrobial activity was assessed by microbroth dilution assay. Quantitative and qualitative analysis of catechins in crude extracts was done by using targeted and auto-MS/MS and correlated with antimicrobial activity. (þ)-Catechin and (þ)-epicatechin and their biosynthesis related compound were found to be up-regulated in regenerated bark and leaves extracts. (?)-Epigallocatechin was found to be significantly higher in bark water extract as compared to others but showed low antimicrobial activity. Result showed down-regulation of (?)-epigallocatechin and up-regulation of (þ)-catechin and (þ)-epicatechin in the regenerated bark and leaves of S. asoca. It might be the contributing factor in the antimicrobial activity of regenerated bark and leaves of the plant. The concentration of (þ)-epicatechin in processed drugs (Ashokarishta) from Baidyanath was found to be seven times higher than that of Dabur Pvt. Ltd., but no antimicrobial activity was observed, indicating the variations among the plant based drugs. This will be helpful in rational use of S. asoca parts. Furthermore, the analytical method developed is sensitive, repeatable and reliable; therefore, it is suitable for quality control of herbal drugs.

  18. Impact of oral green tea catechins on UVR-induced skin inflammation

    OpenAIRE

    Darby, Gemma

    2014-01-01

    Acute exposure of human skin to ultraviolet radiation (UVR) results in oxidative stress and an acute inflammatory response (sunburn), manifest clinically as erythema, histologically by a dermal leukocytic infiltrate and biochemically by upregulation of pro-inflammatory mediators. Green tea catechins (GTC) are potent antioxidants and anti-inflammatory agents with potential to offer systemic photoprotection. We hypothesised that oral GTC are bioavailable in human skin and through cyclooxygenase...

  19. Transcripts of Anthocyanidin Reductase and Leucoanthocyanidin Reductase and Measurement of Catechin and Epicatechin in Tartary Buckwheat

    Directory of Open Access Journals (Sweden)

    Yeon Bok Kim

    2014-01-01

    Full Text Available Anthocyanidin reductase (ANR and leucoanthocyanidin reductase (LAR play an important role in the monomeric units biosynthesis of proanthocyanidins (PAs such as catechin and epicatechin in several plants. The aim of this study was to clone ANR and LAR genes involved in PAs biosynthesis and examine the expression of these two genes in different organs under different growth conditions in two tartary buckwheat cultivars, Hokkai T8 and T10. Gene expression was carried out by quantitative real-time RT-PCR, and catechin and epicatechin content was analyzed by high performance liquid chromatography. The expression pattern of ANR and LAR did not match the accumulation pattern of PAs in different organs of two cultivars. Epicatechin content was the highest in the flowers of both cultivars and it was affected by light in only Hokkai T8 sprouts. ANR and LAR levels in tartary buckwheat might be regulated by different mechanisms for catechin and epicatechin biosynthesis under light and dark conditions.

  20. Separation of catechin epimers by complexation using ion mobility mass spectrometry.

    Science.gov (United States)

    Troć, Anna; Zimnicka, Magdalena; Danikiewicz, Witold

    2015-03-01

    Ion mobility coupled with mass spectrometry provides a fast and repeatable method to separate catechin epimers by previous complexation with selected chiral modifiers and transition metals. Several combinations with chiral ligands such as D- and L-amino acids and/or additional metal cations, chiral crown ethers, tartaric acid and heptakis(2,6-di-O-methyl)-β-cyclodextrin were screened for their ability to affect the separation efficiency. The clusters having the form of [2M + D-amino acid + Cu(2+) - 3H](-) (M stands for (-)-epicatechin or (+)-catechin) showed improvement in stereodifferentiation between two epimeric catechins in comparison to the analysis of pure epimers, where no separation was observed or the separation was hampered by the formation of mixed dimer complexes. Among various examined D-amino acids only those possessing hydrophobic side chains induced the improvement of separation efficiency. The best peak-to-peak resolution (Rp-p) was determined to be 0.71 for [2M + D-Leucine + Cu(2+) - 3H](-) clusters. PMID:25800190

  1. Quantitative Determination of Catechin as Chemical Marker in Pediatric Polyherbal Syrup by HPLC/DAD.

    Science.gov (United States)

    Sheikh, Zeeshan A; Siddiqui, Zafar A; Naveed, Safila; Usmanghani, Khan

    2016-09-01

    Vivabon syrup is a balanced composition of dietary ingredients of phytopharmaceutical nature for maintaining the physique, vigor, vitality and balanced growth of children. The herbal ingredients of pediatric syrup are rich in bioflavonoid, proteins, vitamins, glycosides and trace elements. Vivabon is formulated with herbal drugs such as Phoenix sylvestris, Emblica officinalis, Withania somnifera, Centella asiatica, Amomum subulatum, Zingiber officinalis, Trigonella foenum-graecum, Centaurea behen and Piper longum Catechins are flavan-3-ols that are found widely in the medicinal herbs and are utilized for anti-inflammatory, cardio protective, hepato-protective, neural protection and other biological activities. In general, the dietary intake of flavonoids has been regarded traditionally as beneficial for body growth. Standardization of Vivabon syrup dosage form using HPLC/DAD has been developed for quantitative estimation of Catechin as a chemical marker. The method was validated as per ICH guidelines. Validation studies demonstrated that the developed HPLC method is quite distinct, reproducible as well as quick and fast. The relatively high recovery and low comparable standard deviation confirm the suitability of the developed method for the determination of Catechin in syrup. PMID:27165575

  2. Antiproliferative activity of tea catechins associated with casein micelles, using HT29 colon cancer cells.

    Science.gov (United States)

    Haratifar, S; Meckling, K A; Corredig, M

    2014-02-01

    Numerous studies have shown that green tea polyphenols display anticancer activities in many organ sites by using different experimental models in rodents and in cultured cell lines in vitro. The present study tested the ability of casein micelles to deliver biologically active concentrations of polyphenols to HT-29 colon cancer cells. Epigallocatechin gallate (EGCG), the major catechin found in green tea, was used as the model molecule, as it has been shown to have antiproliferative activity on colon cancer cells. In the present work, we hypothesized that due to the binding of caseins with EGCG, casein micelles may be an ideal platform for the delivery of this bioactive molecule and that the binding would not affect the bioaccessibility of EGCG. The cytotoxicity and proliferation behavior of HT-29 colon cancer cells when exposed to free EGCG was compared with that of nanoencapsulated EGCG in casein micelles of skim milk. Epigallocatechin gallate-casein complexes were able to decrease the proliferation of HT-29 cancer cells, demonstrating that bioavailability may not be reduced by the nanoencapsulation. As casein micelles may act as protective carriers for EGCG in foods, it was concluded that nanoencapsulation of tea catechins in casein micelles may not diminish their antiproliferative activity on colon cancer cells compared with free tea catechins. PMID:24359816

  3. Optimization of Fabrication Parameters to Prepare Tea Catechin-Loaded Liposomes using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Jianjun Fang

    2013-01-01

    Full Text Available The purpose of this study was to optimize the formulation of tea catechin-loaded nano-liposomes using response surface methodology. Response surface methodology based on central composite rotatable design has been successfully used to model and optimize biochemical and biotechnological processes. The mass ratio of phosphatidylcholine and cholesterol (1-3, catechin concentration (3-5 mg/mL, pH values of phosphate buffer solution (6-7 and the volume ratio of organic phase and aqueous phase (2-4 were selected as independent variables with encapsulation efficiency and particle size as dependent variables. For each response, a second-order polynomial model was developed using multiple linear regression analysis. Applying a desirability function method the optimum parameters were: phosphatidylcholine to cholesterol mass ratio of 2.17, catechin concentration of 5 mg/mL, pH values of phosphate buffer solution of 6.62 and organic phase to aqueous phase volume ratio of 3.05. At this optimum point, particle size and encapsulation efficiency were found to be 220 nm and 60.18%, respectively. Furthermore, leakage ratio of nano-liposomes was used to determine the influence of storage period.

  4. Catechins and Procyanidins of Ginkgo biloba Show Potent Activities towards the Inhibition of β-Amyloid Peptide Aggregation and Destabilization of Preformed Fibrils

    OpenAIRE

    Haiyan Xie; Jing-Rong Wang; Lee-Fong Yau; Yong Liu; Liang Liu; Quan-Bin Han; Zhongzhen Zhao; Zhi-Hong Jiang

    2014-01-01

    Catechins and procyanidins, together with flavonoid glycosides and terpene trilactones, are three important categories of components in the standard extract of Ginkgo biloba leaves (EGb761). In this research, catechins and proanthocyanidins were found to exist in both the extract of Ginkgo leaves and Ginkgo products. By comparing with reference compounds, six of them were identified as (+)-catechin, (−)-epicatechin, (−)-gallocatechin, (−)-epigallocatechin and procyanidins B1 and B3. The acti...

  5. Direct interaction of natural and synthetic catechins with signal transducer activator of transcription 1 affects both its phosphorylation and activity

    KAUST Repository

    Menegazzi, Marta

    2013-12-10

    Our previous studies showed that (-)-epigallocatechin-3-gallate (EGCG) inhibits signal transducer activator of transcription 1 (STAT1) activation. Since EGCG may be a promising lead compound for new anti-STAT1 drug design, 15 synthetic catechins, characterized by the (-)-gallocatechin-3-gallate stereochemistry, were studied in the human mammary MDA-MB-231 cell line to identify the minimal structural features that preserve the anti-STAT1 activity. We demonstrate that the presence of three hydroxyl groups of B ring and one hydroxyl group in D ring is essential to preserve their inhibitory action. Moreover, a possible molecular target of these compounds in the STAT1 pathway was investigated. Our results demonstrate a direct interaction between STAT1 protein and catechins displaying anti-STAT1 activity. In particular, surface plasmon resonance (SPR) analysis and molecular modeling indicate the presence of two putative binding sites (a and b) with different affinity. Based on docking data, site-directed mutagenesis was performed, and interaction of the most active catechins with STAT1 was studied with SPR to test whether Gln518 on site a and His568 on site b could be important for the catechin-STAT1 interaction. Data indicate that site b has higher affinity for catechins than site a as the highest affinity constant disappears in the H568ASTAT1 mutant. Furthermore, Janus kinase 2 (JAK2) kinase assay data suggest that the contemporary presence in vitro of STAT1 and catechins inhibits JAK2-elicited STAT1 phosphorylation. The very tight catechin-STAT1 interaction prevents STAT1 phosphorylation and represents a novel, specific and efficient molecular mechanism for the inhibition of STAT1 activation. © Copyright 2014 Federation of European Biochemical Societies. All rights reserved.

  6. Qualitative analysis of catechins from green tea GMB-4 clone using HPLC and LC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    Erna Susanti; Ciptati; Retty Ratnawati; Aulanniam; Achmad Rudijanto

    2015-01-01

    Objective: To identify the bioactive compounds in catechins isolation and its compo-nents from green tea GMB-4 clone. Methods: Green tea GMB-4 clones were extracted with distilled water at 90 ? C. Samples were eluted into the column with 10%ethanol. Subsequently, the column was eluted with 95% ethanol and evaporated separately. Green tea extract was identified by thin layer chromatography. Catechins were separated by the stationary phase in column chroma-tography using polyamide with 10% ethanol eluent and 95% ethanol. The results of isolations were analyzed by high performance liquid chromatographic (HPLC) and LC-MS/MS. Analysis of catechins by HPLC was done by external standard. Results: Fraction from 10% ethanol showed that four major peaks at retention time of 1.663, 2.367, 2.950 and 4.890, indicated the presence of four catechins components including catechin, epicatechins, gallocatechin and epigallocatechin. Whereas, fraction from 95% ethanol showed two main peaks at retention time of 5.167 and 9.82, which indicated the presence of epigallocatechin gallate (EGCG) and epicatechin gallate (ECG). EGCG (m/z 459), epigallocatechin (m/z 307), ECG (m/z 443), and epicatechin (m/z 291) were isolated and separated successfully using HPLC and LC-MS/MS. Conclusions: The HPLC and LC-MS/MS methods were successfully tuned for the qualitative analysis of green tea extract with EGCG and ECG. Four major catechins were separated and identified by LC-MS/MS, such as EGCG, epigallocatechin, ECG and epicatechin. The result of HPLC analysis showed that EGCG and ECG were main components from catechins isolation of green tea GMB-4 clone.

  7. Catechin content and the degree of its galloylation in oolong tea are inversely correlated with cultivation altitude

    Directory of Open Access Journals (Sweden)

    Guan-Heng Chen

    2014-09-01

    Full Text Available The taste quality of oolong tea generated from leaves of Camellia sinensis L. cultivated in the same mountain area is positively correlated to the cultivation altitude, partly due to the inverse correlation with the astringency of the tea infusion. The astringency of oolong tea mostly results from the presence of polyphenolic compounds, mainly catechins and their derivatives. Four catechins, (--epicatechin (EC and (--epigallocatechin (EGC together with their gallate derivatives (with relatively high astringency, (--EC gallate (ECG and (--EGC gallate (EGCG, were detected as major compounds in oolong tea. The degrees of catechin galloylation, designated as ECG/(EC + ECG and EGCG/(EGC + EGCG, in both oolong tea infusions and their fresh tea leaves, were found to be inversely correlated to the cultivation altitude at 200 m, 800 m, and 1300 m. A similar inverse correlation was observed when seven more oolong tea infusions and seven more fresh leaves harvested at altitude ranging from 170 m to 1600 m were recruited for the analyses. Moreover, catechin contents in oolong tea infusions were also found to be inversely correlated to the cultivation altitude. It is proposed that catechin content and the degree of its galloylation account for, at least partly, the inverse correlation between the astringency of oolong tea and the cultivation altitude.

  8. Molecular Docking Studies of Catechin and Its Derivatives as Anti-bacterial Inhibitor for Glucosamine-6-Phosphate Synthase

    Science.gov (United States)

    Fikrika, H.; Ambarsari, L.; Sumaryada, T.

    2016-01-01

    Molecular docking simulation of catechin and its derivatives on Glucosamine-6- Phosphate Synthase (GlmS) has been performed in this research. GlmS inhibition by a particular ligand will suppress the production of bacterial cell wall and significantly reduce the population of invading bacteria. In this study, catechin derivatives i.e epicatechin, galloatechin and epigalloatechin were found to have stronger binding affinities as compared to natural ligand of GlmS, Fructose-6-Phosphate (F6P). Those three ligands were docked on the same pocket in GlmS target as F6P, with 70% binding sites similarity. Based on the docking results, gallocatechin turns out to be the most potent ligand for anti-bacterial agent with ΔG= -8.00 kcal/mol. The docking between GlmS and catechin derivatives are characterized by a constant present of a strong hydrogen bond between functional group O3 and Ser-349. This hydrogen bond most likely plays a significant role in the docking mechanism and binding modes selection. The surprising result is catechin itself exhibited a quite strong binding with GlmS (ΔG= -7.80 kcal.mol), but docked on a completely different pocket compared to other ligands. This results suggest that catechin might still have a curing effect but with a completely different pathway and mechanism as compared to its derivatives.

  9. A novel functional full-fat hard cheese containing liposomal nanoencapsulated green tea catechins: manufacture and recovery following simulated digestion.

    Science.gov (United States)

    Rashidinejad, Ali; Birch, E John; Everett, David W

    2016-07-13

    (+)-Catechin or green tea extract were encapsulated in soy lecithin nanoliposomes and incorporated into a full-fat cheese, then ripened at 8 °C for 90 days. Cheese samples were subjected to simulated gastrointestinal digestion to measure total phenolic content (TPC) and antioxidant activity of the cheese digesta, and to determine the catechin recovery after digestion by high performance liquid chromatography (HPLC). Addition of catechin or green tea extract significantly (P ≤ 0.05) increased TPC and antioxidant activity (measured by ferric reducing antioxidant power and oxygen radical absorbance capacity) of the full-fat cheese without affecting pH or proximate composition. HPLC analysis confirmed retention of encapsulated catechins in the cheese curd; however, individual catechins were recovered in differing amounts (15-52%) from cheese digesta after 6 h of digestion. Transmission electron microscopy and Fourier transform infrared spectroscopy provided evidence for association of nanoliposomes with the surface of milk fat globules inside the cheese matrix. The study shows the potential for using cheese as a delivery vehicle for green tea antioxidants. PMID:27374326

  10. High catechin concentrations detected in Withania somnifera (ashwagandha by high performance liquid chromatography analysis

    Directory of Open Access Journals (Sweden)

    Sulaiman Siti

    2011-08-01

    Full Text Available Abstract Background Withania somnifera is an important medicinal plant traditionally used in the treatment of many diseases. The present study was carried out to characterize the phenolic acids, flavonoids and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH scavenging activities in methanolic extracts of W. somnifera fruits, roots and leaves (WSFEt, WSREt and WSLEt. Methods WSFEt, WSREt and WSLEt was prepared by using 80% aqueous methanol and total polyphenols, flavonoids as well as DPPH radical scavenging activities were determined by spectrophotometric methods and phenolic acid profiles were determined by HPLC methods. Results High concentrations of both phenolics and flavonoids were detected in all parts of the plant with the former ranging between 17.80 ± 5.80 and 32.58 ± 3.16 mg/g (dry weight and the latter ranging between 15.49 ± 1.02 and 31.58 ± 5.07 mg/g. All of the three different plant parts showed strong DPPH radical scavenging activities (59.16 ± 1.20 to 91.84 ± 0.38%. Eight polyphenols (gallic, syringic, benzoic, p-coumaric and vanillic acids as well as catechin, kaempferol and naringenin have been identified by HPLC in parts of the plant as well. Among all the polyphenols, catechin was detected in the highest concentration (13.01 ± 8.93 to 30.61 ± 11.41 mg/g. Conclusion The results indicating that W. somnifera is a plant with strong therapeutic properties thus further supporting its traditional claims. All major parts of W. somnifera such as the roots, fruits and leaves provide potential benefits for human health because of its high content of polyphenols and antioxidant activities with the leaves containing the highest amounts of polyphenols specially catechin with strong antioxidant properties.

  11. Catechin-capped gold nanoparticles: green synthesis, characterization, and catalytic activity toward 4-nitrophenol reduction

    OpenAIRE

    Choi, Yoonho; Choi, Myung-Jin; Cha, Song-Hyun; Kim, Yeong Shik; Cho, Seonho; Park, Youmie

    2014-01-01

    An eco-friendly approach is described for the green synthesis of gold nanoparticles using catechin as a reducing and capping agent. The reaction occurred at room temperature within 1 h without the use of any external energy and an excellent yield (99%) was obtained, as determined by inductively coupled plasma mass spectrometry. Various shapes of gold nanoparticles with an estimated diameter of 16.6 nm were green-synthesized. Notably, the capping of freshly synthesized gold nanoparticles by ca...

  12. Green tea catechins for well-being and therapy: prospects and opportunities

    Directory of Open Access Journals (Sweden)

    Miyoshi N

    2015-12-01

    Full Text Available Noriyuki Miyoshi,1 Monira Pervin,1 Takuji Suzuki,2 Keiko Unno,3 Mamoru Isemura,1 Yoriyuki Nakamura1 1School of Food and Nutritional Sciences, University of Shizuoka, Yada, Shizuoka, Japan; 2Faculty of Education, Art and Science, Yamagata University, Yamagata, Japan; 3School of Pharmaceutical Sciences, University of Shizuoka, Yada, Shizuoka, Japan Abstract: Tea is derived from the leaves and buds of Camellia sinensis (Theaceae plant, and is consumed worldwide. Green tea was discovered in the People's Republic of China approximately 3,000 BC. Lu Yu (733–803 published a book that describes the history of tea, the techniques, and utensils used for manufacturing, the method of preparation, and drinking of tea in the People's Republic of China. Green tea contains various components with specific health-promoting effects and is believed to exert protective effects against diseases such as cancer, obesity, diabetes, hepatitis, and neurodegenerative diseases. Of the various tea components, the polyphenol catechins have been the subject of extensive investigation. Among the catechins, (--epigallocatechin gallate has the strongest bioactivity in most cases. Caffeine induces alertness, decreases the sensation of fatigue, and has a diuretic effect. Theanine and -aminobutyric acid can lower the blood pressure and regulate brain function. Vitamin C exhibits antiscorbutic activity, prevents cataracts, and may boost the immune system. Majority of the scientific evidence based on cellular and animal experiments as well as a number of human epidemiological and intervention studies indicate that green tea and (--epigallocatechin gallate have beneficial health effects against various diseases. However, conflicting results have also been reported. Since confounding factors could affect the results, future studies should be designed to eliminate such factors for better understanding of the benefits of green tea on human health. Genetic and environmental factors

  13. Separation of (+)-catechin and quercetin on mesoporous MCM-41 composites: Dynamics of the sorption of flavonoids

    Science.gov (United States)

    Karpov, S. I.; Korabel'nikova, E. O.

    2015-06-01

    An analysis of conditions for chromatographic separation of quercetin and (+)-catechin based on experimental data and using the equations of an asymptotic model of sorption dynamics for substances characterized by convex isotherms of sorption is presented. The effects of the equilibrium (distribution coefficient) and kinetic (diffusion coefficient) factors on the dynamics of the sorption of flavonoids by ordered mesoporous material of the MCM-41 type and its composites with grafted organosilane groups is considered. The effects of kinetic and equilibrium parameters on the broadening of adsorption fronts is demonstrated with allowance for the inner and outer diffusion limitations of the sorption process.

  14. Effect of tea catechins on the structure of lipid membrane and beta ray-induced lipid peroxidation

    International Nuclear Information System (INIS)

    Tea catechins show various pharmacological effect and is known as one of useful antioxidants. We have reported that tea catechins showed inhibiting effect to β-ray induced lipid peroxidation in the low concentration region up to 5 x 10-5 M in the aqueous liposome suspension system. The initiating radical was thought to be the hydroxyl radical (·OH) formed by the decomposition of' water molecules near the membrane surface. Catechins are adsorbed on the membrane surface and scavenge ·OH which enters in the membrane and initiates lipid peroxidation. Inhibiting ability depended on the degree of partition between membrane and water, and this was one of the evidences of the propriety of the model. In this paper, we report the effect of tea catechins on the lipid peroxidation using a spin probe method and the observation of the figure of the liposome with transmission electron microscope in high concentration region between 5 x 10-5 and 1 x 10-2 M. A spin probe 16NS (16-doxylstearic acid) was mixed with egg yolk phosphatidylcholine, and the lipid was dispersed in phosphate buffer solution forming unilamellar liposome. Catechins, (-)-epicatechin (EC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCg), of various concentrations and then the tritiated water were added to the suspension. Reaction was proceeded at 310 K, and the inhibiting activity was compared using ID50 at which absorbed dose the intensity of 16NS decreases to a half of the initial value. Liposomes were stained with 3% solution of uranium acetate and observed by Hitachi H-7500 Electron Microscope. Fig. 1 shows the concentration dependence of ID50 of catechins. EC and ECg showed inhibiting effect in whole region and looked to converge. But EGCg had the maximum point. Below the point, it showed the strongest activity among four catechins. EGC showed slow decrease in whole region. We considered these results as follows. Catechins possessing gallate group have

  15. Catechin-capped gold nanoparticles: green synthesis, characterization, and catalytic activity toward 4-nitrophenol reduction

    Science.gov (United States)

    Choi, Yoonho; Choi, Myung-Jin; Cha, Song-Hyun; Kim, Yeong Shik; Cho, Seonho; Park, Youmie

    2014-03-01

    An eco-friendly approach is described for the green synthesis of gold nanoparticles using catechin as a reducing and capping agent. The reaction occurred at room temperature within 1 h without the use of any external energy and an excellent yield (99%) was obtained, as determined by inductively coupled plasma mass spectrometry. Various shapes of gold nanoparticles with an estimated diameter of 16.6 nm were green-synthesized. Notably, the capping of freshly synthesized gold nanoparticles by catechin was clearly visualized with the aid of microscopic techniques, including high-resolution transmission electron microscopy, atomic force microscopy, and field emission scanning electron microscopy. Strong peaks in the X-ray diffraction pattern of the as-prepared gold nanoparticles confirmed their crystalline nature. The catalytic activity of the as-prepared gold nanoparticles was observed in the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4. The results suggest that the newly prepared gold nanoparticles have potential uses in catalysis.

  16. Use of positron emission tomography for real-time imaging of biodistribution of green tea catechin.

    Directory of Open Access Journals (Sweden)

    Kosuke Shimizu

    Full Text Available The aim of this study was to achieve real-time imaging of the in vivo behavior of a green tea polyphenol, catechin, by positron emission tomography (PET. Positron-labeled 4″ -[(11C]methyl-epigallocatechin gallate ([(11C]Me-EGCG was orally administered to rats, and its biodistribution was imaged for 60 min by using a small animal PET system. As the result, images of [(11C]Me-EGCG passing through the stomach into the small intestines were observed; and a portion of it was quantitatively detected in the liver. On the other hand, intravenous injection of [(11C]Me-EGCG resulted in a temporal accumulation of the labeled catechin in the liver, after which almost all of it was transferred to the small intestines within 60 min. In the present study, we succeeded in obtaining real-time imaging of the absorption and biodistribution of [(11C]Me-EGCG with a PET system.

  17. Modulatory effects of catechin hydrate against genotoxicity, oxidative stress, inflammation and apoptosis induced by benzo(a)pyrene in mice.

    Science.gov (United States)

    Shahid, Ayaz; Ali, Rashid; Ali, Nemat; Hasan, Syed Kazim; Bernwal, Preeti; Afzal, Shekh Mohammad; Vafa, Abul; Sultana, Sarwat

    2016-06-01

    Benzo(a)pyrene [B(a)P], a polycyclic aromatic hydrocarbon (PAH) is a strong mutagen and potent carcinogen. The aim of the present study was to investigate the efficacy of catechin hydrate against B(a)P induced genotoxicity, oxidative stress, inflammation, apoptosis and to explore its underlying molecular mechanisms in the lungs of Swiss albino mice. Administration of B(a)P (125 mg/kg b. wt., p. o.) increased the activities of toxicity markers such as LPO, LDH and B(a)P metabolizing enzymes [NADPH-cytochrome P450 reductase (CYPOR) and microsomal epoxide hydrolase (mEH)] with subsequent decrease in the activities of tissue anti-oxidant armory (SOD, CAT, GPx, GR, GST, QR and GSH). It also caused DNA damage and activation of apoptotic and inflammatory pathway by upregulation of TNF-α, IL-6, NF-kB, COX-2, p53, bax, caspase-3 and down regulating Bcl-2. However, pre-treatment with catechin at a dose of 20 and 40 mg/kg significantly decreased LDH, LPO, B(a)P metabolizing enzymes and increased anti-oxidant armory as well as regulated apoptosis and inflammation in lungs. Histological results also supported the protective effects of catechin. The findings of the present studies suggested that catechin as an effective natural product attenuates B(a)P induced lung toxicity. PMID:27020533

  18. Rapid tea catechins and caffeine determination by HPLC using microwave-assisted extraction and silica monolithic column.

    Science.gov (United States)

    Rahim, A A; Nofrizal, S; Saad, Bahruddin

    2014-03-15

    A rapid reversed-phase high performance liquid chromatographic method using a monolithic column for the determination of eight catechin monomers and caffeine was developed. Using a mobile phase of water:acetonitrile:methanol (83:6:11) at a flow rate of 1.4 mL min(-1), the catechins and caffeine were isocratically separated in about 7 min. The limits of detection and quantification were in the range of 0.11-0.29 and 0.33-0.87 mg L(-1), respectively. Satisfactory recoveries were obtained (94.2-105.2 ± 1.8%) for all samples when spiked at three concentrations (5, 40 and 70 mg L(-1)). In combination with microwave-assisted extraction (MAE), the method was applied to the determination of the catechins and caffeine in eleven tea samples (6 green, 3 black and 2 oolong teas). Relatively high levels of caffeine were found in black tea, but higher levels of the catechins, especially epigallocatechin gallate (EGCG) were found in green teas. PMID:24206716

  19. Liquid chromatographic determination of methylxanthines and catechins in herbal preparations containing guaraná.

    Science.gov (United States)

    Carlson, M; Thompson, R D

    1998-01-01

    Herbal preparations derived from the dried seeds of guaraná (Paullinia cupana) have become a popular nutritional supplement used for stimulatory purposes. Once considered a drug substance in the United States, guaraná currently is classified as a food additive and dietary supplement. The pharmacological activity of guaraná-containing products is primarily due to methylxanthine alkaloids. For guaraná preparations, methylxanthine levels and, more significantly, the presence of several polyphenol compounds (i.e., catechins) provide phytochemical markers of authenticity. Methylxanthines and polyphenols are extracted from sample matrix with a heated phosphate buffer-methanol solution, the cooled extract is filtered, and the extract is injected into the liquid chromatographic (LC) system. A Nova-Pak C18 column eluted with phosphate buffer-methanol mobile phase (pH = 3.50) and monitored at 272 nm gave satisfactory resolution for the methylxanthines theobromine, theophylline, caffeine and the polyphenols (+)-catechin and (-)-epicatechin. Twenty-four products including dried seeds, dried paste, seed powders, tablets, and capsule formulations were assayed and conclusions were drawn about their authenticity. The LC system responded linearly to methylxanthines over the 100-fold range in concentration from 0.043 to 4.30 micrograms/mL for theobromine and caffeine and from 0.041 to 4.10 micrograms/mL for theophylline. Precision data for the 3 methylxanthines obtained from 10 different products (n = 5) gave relative standard deviation (RSD) values of 1.18-15.52% within a concentration range of 0.01-52.28 mg/g. Recoveries of methylxanthines from fortified products varied from 87.5 to 120.0%. The response for catechins was linear over a 200-fold range in concentration of 0.05-10.0 micrograms/mL. Precision data from 5 products (n = 5) gave RSD values of 1.08-5.54% within a concentration range of 0.34-32.65 mg/g. Recoveries from these products ranged from 87.7 to 109.7%. Results

  20. Evaluation of the bitterness of green tea catechins by a cell-based assay with the human bitter taste receptor hTAS2R39.

    Science.gov (United States)

    Narukawa, Masataka; Noga, Chiaki; Ueno, Yohei; Sato, Tsutomu; Misaka, Takumi; Watanabe, Tatsuo

    2011-02-25

    Catechins have a broad range of physiological functions and act as the main taste ingredient of green tea. Although catechins show a strong bitterness, the bitter taste receptor for catechins has not been fully understood. The objective of this study was to identify the receptor for the major green tea catechins such as (-)-epicatechin (EC), (-)-epicatechin gallate (ECg), (-)-epigallocatechin (EGC), and (-)-epigallocatechin gallate (EGCg). By the cell-based assay using cultured cells expressing human bitter taste receptor, a clear response of hTAS2R39-expressing cells was observed to 300μM of either ECg or EGCg, which elicit a strong bitterness in humans. The response of hTAS2R39-expressing cells to ECg was the strongest among the tested catechins, followed by EGCg. Because the cellular response to EC and EGC is much weaker than those of ECg and EGCg, galloyl groups was strongly supposed to be involved in the bitter intensity. This finding is similar to the observations of taste intensity obtained from a human sensory study. Our results suggest the participation of hTAS2R39 in the detection of catechins in humans, indicating the possibility that bitterness of tea catechins can be evaluated by using cells expressing hTAS2R39. PMID:21272567

  1. The profiling and identification of the metabolites of (+)-catechin and study on their distribution in rats by HPLC-DAD-ESI-IT-TOF-MS(n) technique.

    Science.gov (United States)

    Liang, Jing; Xu, Feng; Zhang, Ya-Zhou; Zang, Xin-Yu; Wang, Dan; Shang, Ming-Ying; Wang, Xuan; Chui, De-Hua; Cai, Shao-Qing

    2014-03-01

    (+)-Catechin, a potential beneficial compound to human health, is widely distributed in plants and foods. A high-performance liquid chromatography with diode array detector and combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry method was applied to profile and identify the metabolites of (+)-catechin in rats and to study the distribution of these metabolites in rat organs for the first time. In total, 51 phase II metabolites (44 new) and three phase I metabolites were tentatively identified, comprising 16 (+)-catechin conjugates, 14 diarylpropan-2-ol metabolites, 6 phenyl valerolactone metabolites and 18 aromatic acid metabolites. Further, 19 phase II metabolites were new compounds. The in vivo metabolic reactions of (+)-catechin in rats were found to be ring-cleavage, sulfation, glucuronidation, methylation, dehydroxylation and dehydrogenation. The numbers of detected metabolites in urine, plasma, small intestine, kidney, liver, lung, heart, brain and spleen were 53, 23, 27, 9, 7, 5, 3, 2 and 1, respectively. This indicated that small intestine, kidney and liver were the major organs for the distribution of (+)-catechin metabolites. In addition, eight metabolites were found to possess bioactivities according to literature. These results are very helpful for better comprehension of the in vivo metabolism of (+)-catechin and its pharmacological actions, and also can give strong indications on the effective forms of (+)-catechin in vivo. PMID:24105958

  2. Characterization of Catechins in Water by Photoemission Yield Spectroscopy in Air.

    Science.gov (United States)

    Yamashita, Daisuke; Ishizaki, Atsushi

    2016-01-01

    Photoemission yield spectroscopy in air (PYSA) was applied for the characterization of catechins in water in ambient conditions. According to the results of measurements on aqueous solutions of epigallocatechin gallate (EGCg) of various concentrations, the photoemission yield is almost proportional to the concentration of EGCg. Contrarily, the threshold energy of photoemission, EPET, is almost constant at 5.46 ± 0.02 eV. Moreover, we measured aqueous solutions of epicatechin (EC), epigallocatechin (EGC), and epicatechin gallate (ECg). The values of EPET of EC, EGC, ECg were estimated to be 5.72 ± 0.02, 5.68 ± 0.01, and 5.45 ± 0.02 eV, respectively, and a dependence on the molecular structure was found. Furthermore, changes in the photoemission yield spectra of heated EGCg were well explained by molecular orbital calculations on the basis of an assumption of epimerization. PMID:27169659

  3. Separation of catechins and O-methylated (-)-epigallocatechin gallate using polyamide thin-layer chromatography.

    Science.gov (United States)

    Wang, Kunbo; Chen, Qincao; Lin, Yong; Yu, Shuangshang; Lin, Haiyan; Huang, Jianan; Liu, Zhonghua

    2016-04-01

    Thin-layer chromatography (TLC) method for the separation and quantitative determination of seven related compounds: (+)-catechin (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3″Me) and (-)-epigallocatechin- 3-O-(4-O-methyl) gallate (EGCG4″Me) has been developed. The above-mentioned seven compounds have been resolved using polyamide TLC plates using a double-development with methanol followed by acetone/acetic acid (2:1, v/v). In addition, separation of the phenolic acids namely gallic acid, chlorogenic acid, and caffeic acid was achieved using the same solvent system. The applicability of the method was checked by screening of extracts of green, black, oolong, white tea and tea cultivars leaves. PMID:26990737

  4. Effect of catechins and tannins on hydroxyl radical formation in depleted uranium-hydrogen peroxide systems

    International Nuclear Information System (INIS)

    The effects of catechins and tannins on the uranyl ion (UO2+2)-hydrogen peroxide (H2O2) system were examined using the spin-trapping method. Epigallocatechin (EGC), having low ·OH-scavenging ability, significantly enhanced and accelerated the hydroxyl radical (·OH) formation in the UO2+2-H2O2 solution. Epigallocatechin gallate (EGCG), having high ·OH-scavenging ability, fairly enhanced and accelerated hydroxyl radical (·OH) formation in the UO2+2-H2O2 solution. These results indicate that the enhancement and acceleration of ·OH formation are caused by the reduction of UO2+2 to UO2+ by EGC and EGCG. The effects of tannins on ·OH formation in the UO2+2-H2O2 solution varied with tannins. Mimosa (MMT) and quebracho (QBT) tannins enhanced and accelerated ·OH formation, while chestnut (CNT), mylobaran (MBT) and Chinese gallo- (CGT) tannins heavily depressed it. In the solution containing persimmon (PST) and gambir (GBT) tannins, the depression of ·OH formation caused by the strong coupling with UO2+2 ion should be added to the enhancement caused by the reduction of UO2+2 to UO2+. MBT indicated the highest ability to scavenge ·OH in the UV-irradiated H2O2 solution, and MMT, the lowest. In summary, MMT and QBT, classified as condensed tannins, have very high abilities to reduce UO2+2 to UO2+, similarly to catechins such as EGC and EGCG, while MBT, a hydrolysable tannin, has higher abilities to scavenge ·OH. (author)

  5. Determination of catechin in green tea using a catechol oxidase biomimetic sensor

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Suellen C.; Osorio, Renata El-Hage M. de Barros; Anjos, Ademir dos; Neves, Ademir; Micke, Gustavo Amadeu; Vieira, Iolanda C. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Quimica]. E-mail: iolanda@qmc.ufsc.br

    2008-07-01

    A catechol oxidase biomimetic sensor, based on a novel copper(II) complex, was developed for the determination of catechin in green tea and the results were compared with those obtained by capillary electrophoresis. The dinuclear copper(II) complex, [Cu{sub 2}(HL)({mu}-CH{sub 3}COO)](ClO{sub 4}), containing the ligand N,N-[bis-(2-pyridylmethyl)]-N',N'-[(2-hydroxybenzyl)(2-hydroxy-3,5-di-tert - butylbenzyl)]-1,3-propanediamine-2-ol (H{sub 3}L), was synthesized and characterized by IR, {sup 1}H NMR and elemental analysis. The best conditions for the optimization of the biomimetic sensor were established by square wave voltammetry. The best performance for this sensor was obtained in 75:15:10% (m/m/m) of the graphite powder:nujol:copper(II) complex, 0.05 mol L{sup -1} phosphate buffer solution (pH 7.5) and frequency, pulse amplitude, scan increment at 30 Hz, 80 mV, 3.3 mV, respectively. The analytical curve was linear in the concentration range 4.95 x 10{sup -6} to 3.27 x 10{sup -5} mol L{sup -1} (r = 0.9993) with a detection limit of 2.8 x 10{sup -7} mol L{sup -1}. This biomimetic sensor demonstrated long-term stability (9 months; 800 determinations) and reproducibility with a relative standard deviation of 3.5%. The recovery of catechin from green tea samples ranged from 93.8 to 106.9% and the determination, compared with that obtained using capillary electrophoresis, was found to be acceptable at the 95% confidence level. (author)

  6. Determination of catechin in green tea using a catechol oxidase biomimetic sensor

    International Nuclear Information System (INIS)

    A catechol oxidase biomimetic sensor, based on a novel copper(II) complex, was developed for the determination of catechin in green tea and the results were compared with those obtained by capillary electrophoresis. The dinuclear copper(II) complex, [Cu2(HL)(μ-CH3COO)](ClO4), containing the ligand N,N-[bis-(2-pyridylmethyl)]-N',N'-[(2-hydroxybenzyl)(2-hydroxy-3,5-di-tert - butylbenzyl)]-1,3-propanediamine-2-ol (H3L), was synthesized and characterized by IR, 1H NMR and elemental analysis. The best conditions for the optimization of the biomimetic sensor were established by square wave voltammetry. The best performance for this sensor was obtained in 75:15:10% (m/m/m) of the graphite powder:nujol:copper(II) complex, 0.05 mol L-1 phosphate buffer solution (pH 7.5) and frequency, pulse amplitude, scan increment at 30 Hz, 80 mV, 3.3 mV, respectively. The analytical curve was linear in the concentration range 4.95 x 10-6 to 3.27 x 10-5 mol L-1 (r = 0.9993) with a detection limit of 2.8 x 10-7 mol L-1. This biomimetic sensor demonstrated long-term stability (9 months; 800 determinations) and reproducibility with a relative standard deviation of 3.5%. The recovery of catechin from green tea samples ranged from 93.8 to 106.9% and the determination, compared with that obtained using capillary electrophoresis, was found to be acceptable at the 95% confidence level. (author)

  7. Preparation, characterization and evaluation of antibacterial activity of catechins and catechins-Zn complex loaded β-chitosan nanoparticles of different particle sizes.

    Science.gov (United States)

    Zhang, Hongcai; Jung, Jooyeoun; Zhao, Yanyun

    2016-02-10

    This study used β-chitosan nanoparticles (β-CS NPs) of different particle sizes to encapsulate catechins (CAT) or CAT-Zn complex by ionic gelation technology. The antibacterial activity of CAT or CAT-Zn complex loaded β-CS NPs against Escherichia coli and Listeria innocua were investigated based on bacterial growth curve, minimum inhibitory concentration (MIC), and minimum bacterial concentration (MBC). Fourier transform infrared spectrometer (FT-IR) was employed to study the incorporation of CAT or CAT-Zn complex into β-CS NPs. The CAT-Zn complex loaded β-CS NPs had particle size of 208-591 nm, polydispersity index (PDI) of 0.377-0.395, and positive Zeta-potential of 39.17-45.62 mV. The CAT-Zn complex loaded β-CS NPs of smaller particle sizes showed higher antibacterial activity than that of larger particle size ones. The MIC and MBC of CAT-Zn complex loaded β-CS NPs of the smallest particle size against L. innocua and E. coli were 0.031 and 0.063 mg/mL, and 0.063 and 0.125 mg/mL, respectively. This study suggested that encapsulation of CAT-Zn complex in β-CS NPs improved the antibacterial activity of CAT and CAT-Zn complex, and the encapsulators have great potential to be used as antibacterial substances for food and other applications through either direct addition or incorporation into packaging materials. PMID:26686108

  8. [Rapid and Dynamic Determination Models of Amino Acids and Catechins Concentrations during the Processing Procedures of Keemun Black Tea].

    Science.gov (United States)

    Ning, Jing-ming; Yan, Ling; Zhang, Zheng-zhu; Wei, Ling-dong; Li, Lu-qing; Fang, Jun-ting; Huang, Cai-wang

    2015-12-01

    Tea is one of the most popular beverages in the world. For the contribution to the taste and healthy functions of tea, amino acids and catechins are important components. Among different kinds of black teas in the world, Keemun black tea has the famous and specific fragrance, "Keemun aroma". During the processing procedure of Keemun black tea, the contents of amino acids and catechins changed greatly, and the differences of these concentrations during processing varied significantly. However, a rapid and dynamic determination method during the processing procedure was not existed up to now. In order to find out a rapid determination method for the contents of amino acids and catechins during the processing procedure of Keemun black tea, the materials of fresh leaves, withered leaves, twisted leaves, fermented leaves, and crude tea (after drying) were selected to acquire their corresponding near infrared spectroscopy and obtain their contents of amino acids and catechins by chemical analysis method. The original spectra data were preprocessed by the Standard Normal Variate Transformation (SNVT) method. And the model of Near Infrared (NIR) spectroscopy with the contents of amino acids and catechins combined with Synergy Interval Partial Least squares (Si-PLS) was established in this study. The correlation coefficients and the cross validation root mean square error are treated as the efficient indexes for evaluating models. The results showed that the optimal prediction model of amino acids by Si-PLS contained 20 spectral intervals combined with 4 subintervals and 9 principal component factors. The correlation coefficient and the root mean square error of the calibration set were 0. 955 8 and 1. 768, respectively; the correlation coefficient and the root mean square error of the prediction set were 0. 949 5 and 2. 16, respectively. And the optimal prediction model of catechins by Si-PLS contained 20 spectral intervals combined with 3 subintervals and 10 principal

  9. Preparation of catechin extracts and nanoemulsions from green tea leaf waste and their inhibition effect on prostate cancer cell PC-3.

    Science.gov (United States)

    Tsai, Yin-Jieh; Chen, Bing-Huei

    2016-01-01

    Green tea is one of the most commonly consumed natural health beverages in Taiwan's market, with the major functional component catechin being shown to possess several biological activities such as antioxidation, anticancer, and prevention of cardiovascular disease. The objectives of this study were to develop a high-performance liquid chromatography-mass spectrometry method to determine the variety and content of catechins in green tea leaf waste, a by-product obtained during processing of tea beverage. In addition, catechin nanoemulsion was prepared to study its inhibition effect on prostate cancer cell PC-3. Results showed that a total of eight catechin standards were separated within 25 minutes by using a Gemini C18 column and a gradient mobile phase of 0.1% formic acid (A) and acetonitrile (B) with flow rate at 1 mL/min, column temperature at 30°C, and detection wavelength at 280 nm. Among various extraction solvents, 50% ethanol generated the highest yield of total catechins from tea leaf waste, of which five catechins were identified and quantified. The catechin nanoemulsion was composed of catechin extract, lecithin, Tween 80, and deionized water in an appropriate proportion, with the mean particle size being 11.45 nm, encapsulation efficiency 88.1%, and zeta potential -66.3 mV. A high stability of catechin nanoemulsion was shown over a storage period of 120 days at 4°C. Both catechin extract and nanoemulsion could inhibit growth of PC-3 tumor cells, with the half maximal inhibitory concentration being 15.4 μg/mL and 8.5 μg/mL, respectively. The PC-3 cell cycle was arrested at S phase through elevation of P27 expression and decline of cyclin A, cyclin B, cyclin-dependent kinase 2, and cyclin-dependent kinase 1 expression. In addition, both catechin extract and nanoemulsion could induce apoptosis of PC-3 cells through decrease in B-cell lymphoma 2 (bcl-2) expression and increase in cytochrome c expression for activation of caspase-3, caspase-8, and

  10. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation ☆ ☆☆ ★

    OpenAIRE

    Clarke, Kayleigh A; Dew, Tristan P; Watson, Rachel E.B.; Farrar, Mark D.; Osman, Joanne E.; Nicolaou, Anna; Rhodes, Lesley E; Williamson, Gary

    2016-01-01

    Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin level...

  11. Catechins and Procyanidins of Ginkgo biloba Show Potent Activities towards the Inhibition of β-Amyloid Peptide Aggregation and Destabilization of Preformed Fibrils

    Directory of Open Access Journals (Sweden)

    Haiyan Xie

    2014-04-01

    Full Text Available Catechins and procyanidins, together with flavonoid glycosides and terpene trilactones, are three important categories of components in the standard extract of Ginkgo biloba leaves (EGb761. In this research, catechins and proanthocyanidins were found to exist in both the extract of Ginkgo leaves and Ginkgo products. By comparing with reference compounds, six of them were identified as (+-catechin, (−-epicatechin, (−-gallocatechin, (−-epigallocatechin and procyanidins B1 and B3. The activities of these polyphenols in the inhibition of Aβ42 aggregation and the destabilization of preformed fibrils were evaluated using biochemical assays, which showed that all six of the polyphenols, as well as a fraction of the extract of Ginkgo biloba leaves (EGb containing catechins and procyanidins, exerted potent inhibitory activities towards Aβ42 aggregation and could also destabilize the performed fibrils. Catechins and procyanidins can therefore be regarded as the potent active constituents of EGb761 in terms of their inhibition of Aβ42 aggregation and destabilization of the fibrils. Although quantitative mass spectroscopic analysis revealed that the catechins and procyanidins are only present in low concentrations in EGb761, these components should be studied in greater detail because of their potent inhibitory effects towards Aβ42 aggregation and their ability to destabilize preformed fibrils, especially during the quality control of Ginkgo leaves and the manufacture of Ginkgo products.

  12. Characterization of catechin-α-lactalbumin conjugates and the improvement in β-carotene retention in an oil-in-water nanoemulsion.

    Science.gov (United States)

    Yi, Jiang; Fan, Yuting; Zhang, Yuzhu; Zhao, Liqing

    2016-08-15

    The goal of this study was to prepare and characterize α-lactalbumin (ALA)-catechin conjugates as a novel emulsifier in improving the retention of β-carotene (BC) in nanoemulsions via a free radical method. Covalent modification was observed and at least one catechin molecule was binding with ALA according to ESI-MS results. Far-UV CD indicated that the secondary structure of ALA was changed after conjugation. The Z-average particle diameters of nanoemulsions stabilized with ALA and ALA-catechin conjugates were 158.8 and 162.7nm, respectively. The increase of mean particle size and the degradation of BC at 50°C were both larger than at 25°C during 30days storage. BC retention stabilized with ALA-catechin conjugates was appreciably greater than ALA (control), which was attributed to the increase of ALA's radicals-scavenging and free metal ion binding ability after grafting with catechin. The chemical antioxidant activities of ALA-catechin conjugates were increased with increasing concentrations from 0.1 to 1.0mg/ml. In general, labile phytochemicals, like BC, can be protected against oxidation during storage by proteins-polyphenols conjugates without any side effects. PMID:27006216

  13. Binding Inhibition Between Igf1r and Igf1 by Catechin of Black Tea

    Directory of Open Access Journals (Sweden)

    Lina Firdausi

    2012-12-01

    Full Text Available The natural compound of black tea is used as an alternative of obesity therapies in the world; particularly, the catechin family in tea leaves which has bioactive compounds such as EC, EGC and EGCG. Their bioactivity contributes to inhibit the ligand of Insulin-Like Growth Factor I Receptor (Igf-1r binding-region to Igf-1 protein. To elucidate the inhibiton of Igf-1 expression and proliferating of Rattus norvegicus strain wistar adipose cell using black tea solution. The research used Rattus norvegicus strain wistar. After a 90-day treatment, the adipose tissues were picked up from the viscera of each experimental animal, and then the adipose tissues were embedded by paraffin. The paraffin sections were determined through immunohistochemistry with anti-Igf-1 antiserum, and were also analyzed through hematoxylin-eosin. A protein sequence of Igf-1, Igf-1r, and 3D structure of EC, EGC and EGCG from Gene Bank sites were used during in silico analysis. The sequences were aligned by BLAST program to identify the conserve and variable domain of IGF-1 protein isoforms. The 3D structures of IGF-1 and IGF-1R were constructed using Phyre program. The ligand among the 3D structures of IGF-1, IGF-1R and catechin compounds were analyzed using Hex 5.1 docking program. The data showed that the Igf-1 expression of adipose cells was reduced at 0,03 g/ml BTS and 0,045 g/ml BTS treatments. The result of BLAST analysis showed that IGF-1 (a, b, c, and d isoforms conserved a domain from amino acid no 22 until 134; and this region was a variable region. The EGCG bound L1 domain of IGF-1R with E-total -235.3 KJ/mol which was lower than EC (-208,4 KJ/mol and EGC (-142 KJ/mol. The total energy of IGF-1 (a, b, c, but not d isoform which interacted with EGCG was around -223.7 KJ/mol, EC is -205.6 KJ/mol and EGC was -191.7 KJ/mol. However, EC, EGC and EGCG was only able to prevent the interaction between the L1 of IGF-1R with IGF-1 protein, but not the opposite.

  14. Purification and Characterization of a Novel Galloyltransferase Involved in Catechin Galloylation in the Tea Plant (Camellia sinensis)*

    Science.gov (United States)

    Liu, Yajun; Gao, Liping; Liu, Li; Yang, Qin; Lu, Zhongwei; Nie, Zhiyin; Wang, Yunsheng; Xia, Tao

    2012-01-01

    Catechins (flavan-3-ols), the most important secondary metabolites in the tea plant, have positive effects on human health and are crucial in defense against pathogens of the tea plant. The aim of this study was to elucidate the biosynthetic pathway of galloylated catechins in the tea plant. The results suggested that galloylated catechins were biosynthesized via 1-O-glucose ester-dependent two-step reactions by acyltransferases, which involved two enzymes, UDP-glucose:galloyl-1-O-β-d-glucosyltransferase (UGGT) and a newly discovered enzyme, epicatechin:1-O-galloyl-β-d-glucose O-galloyltransferase (ECGT). In the first reaction, the galloylated acyl donor β-glucogallin was biosynthesized by UGGT from gallic acid and uridine diphosphate glucose. In the second reaction, galloylated catechins were produced by ECGT catalysis from β-glucogallin and 2,3-cis-flavan-3-ol. 2,3-cis-Flavan-3-ol and 1-O-galloyl-β-d-glucose were appropriate substrates of ECGT rather than 2,3-trans-flavan-3-ol and 1,2,3,4,6-pentagalloylglucose. Purification by more than 1641-fold to apparent homogeneity yielded ECGT with an estimated molecular mass of 241 to 121 kDa by gel filtration. Enzyme activity and SDS-PAGE analysis indicated that the native ECGT might be a dimer, trimer, or tetramer of 60- and/or 58-kDa monomers, and these monomers represent a heterodimer consisting of pairs of 36- or 34- of and 28-kDa subunits. MALDI-TOF-TOF MS showed that the protein SCPL1199 was identified. Epigallocatechin and epicatechin exhibited higher substrate affinities than β-glucogallin. ECGT had an optimum temperature of 30 °C and maximal reaction rates between pH 4.0 and 6.0. The enzyme reaction was inhibited dramatically by phenylmethylsulfonyl fluoride, HgCl2, and sodium deoxycholate. PMID:23132863

  15. A randomized controlled trial of green tea catechins in protection against ultraviolet radiation-induced cutaneous inflammation.

    OpenAIRE

    Farrar, Mark D; Nicolaou, Anna; Clarke, Kayleigh A; Mason, Sarah,; Massey, Karen A.; Dew, Tristan P; Watson, Rachel EB; Williamson, Gary; Rhodes, Lesley E; Farrar MD, Nicolaou A, Clarke KA, Mason S, Massey KA, Dew TP, Watson REB, Williamson G, Rhodes LE

    2015-01-01

    BACKGROUND: Safe systemic protection from the health hazards of ultraviolet radiation (UVR) in sunlight is desirable. Green tea is consumed globally and is reported to have anti-inflammatory properties, which may be mediated through the impact on cyclooxygenase and lipoxygenase pathways. Recent data suggest that green tea catechins (GTCs) reduce acute UVR effects, but human trials examining their photoprotective potential are scarce. OBJECTIVE: We performed a double-blind, randomized, placebo...

  16. Determination of Catechin Content in Gambir Powder from Dried Gambir Leaves Quickly using FT NIR PLS Model

    Directory of Open Access Journals (Sweden)

    Andasuryani Andasuryani

    2014-01-01

    Full Text Available Conventional production process of gambir often produces gambir with low content of catechin. Engineering of production processes of gambir leaves to produce gambir powder has been developed by previous researchers. The objective of this study was to develop a calibration model to predict the content of catechin in gambir powder from dried gambir leaves quickly using FT-NIR PLS model.  Reflectance spectra of gambir powder from dried gambir leaves obtained at a wavelength of 1000 to 2500 nm. Spectra pre-processing treatment method used was a combination between normalization between 0 and 1 (n01 method and first derivative Savitzky-Golay 9 points (dg1. The result showed that correlation coefficient and standard error of prediction (SEP were 0.99 and 2.10 % respectively, obtained when used 6 factors of partial least square (PLS. Calibration model developed has shown higher accuracy and precision to predict catechin content of gambir powder from dried gambir leaves.

  17. Study on inhibition mechanism of tea catechins on beta-ray-induced lipid peroxidation by examination shapes of liposome

    International Nuclear Information System (INIS)

    Previous studies have indicated that the inhibiting effect decreased with increasing of the concentration of (-)-epigallocatechin gallate (EGCg), which is one of tea catechins, above 5 x 10-5 M, and interaction of EGCg with lipid membrane would induce the decrease of inhibiting effect. In this present study, to elucidate the mechanism of decrease of the inhibiting effect, shape changes of lipid membrane by four kinds of tea catechins (EGCg), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epicatechin (EC)) were observed by absorptiometer and transmission electron microscope. These results suggested that EGCg induced aggregation of liposomes and shapes change of the membrane. In addition, the influence of hydrogen peroxide (H2O2) induced by autoxidation of catechin was measured by electron spin resonance to elucidate influence of autoxidation of EGCg on the decrease of inhibiting effect. This result suggested that the decrease of the inhibiting effect didn't be caused by the H2O2, but induced by shapes change of the lipid membrane due to EGCg. (author)

  18. Self-assembled ternary complexes stabilized with hyaluronic acid-green tea catechin conjugates for targeted gene delivery.

    Science.gov (United States)

    Liang, Kun; Bae, Ki Hyun; Lee, Fan; Xu, Keming; Chung, Joo Eun; Gao, Shu Jun; Kurisawa, Motoichi

    2016-03-28

    Nanosized polyelectrolyte complexes are attractive delivery vehicles for the transfer of therapeutic genes to diseased cells. Here we report the application of self-assembled ternary complexes constructed with plasmid DNA, branched polyethylenimine and hyaluronic acid-green tea catechin conjugates for targeted gene delivery. These conjugates not only stabilize plasmid DNA/polyethylenimine complexes via the strong DNA-binding affinity of green tea catechin, but also facilitate their transport into CD44-overexpressing cells via receptor-mediated endocytosis. The hydrodynamic size, surface charge and physical stability of the complexes are characterized. We demonstrate that the stabilized ternary complexes display enhanced resistance to nuclease attack and polyanion-induced dissociation. Moreover, the ternary complexes can efficiently transfect the difficult-to-transfect HCT-116 colon cancer cell line even in serum-supplemented media due to their enhanced stability and CD44-targeting ability. Confocal microscopic analysis demonstrates that the stabilized ternary complexes are able to promote the nuclear transport of plasmid DNA more effectively than binary complexes and hyaluronic acid-coated ternary complexes. The present study suggests that the ternary complexes stabilized with hyaluronic acid-green tea catechin conjugates can be widely utilized for CD44-targeted delivery of nucleic acid-based therapeutics. PMID:26855049

  19. Measurement of Antioxidant Activity of Wine Catechins, Procyanidins, Anthocyanins and Pyranoanthocyanins

    Directory of Open Access Journals (Sweden)

    Julián C. Rivas-Gonzalo

    2007-08-01

    Full Text Available Nowadays, there is considerable interest in finding out about antioxidants thatare consumed in the habitual diet. It is known that polyphenols are involved in reducing therisk of diseases associated with oxidative stress. The in vitro antioxidant activity of theprincipal wine polyphenolic compounds (catechins, procyanidins, anthocyanins andpyranoanthocyanins was studied in this work. Four distinct methods were used to assessthe antioxidant capacity of the tested compounds: inhibition of peroxynitrite mediatedtyrosine nitration, TEAC (Trolox equivalent antioxidant capacity assay, FRAP (Ferricreducing/antioxidant power assay and TBARS (thiobarbituric acid reactive substancesmethods. In general, it could be concluded that procyanidins were, among the in vitrotested groups, the ones which showed more antioxidant capacity using the four differentmethods, followed by anthocyanins and pyranoanthocyanins. On the basis of the simpleregression testing, there was a statistically significant relationship between these differentmethods used in aqueous phase (r > 0.92. However, no correlation was found between theresults obtained in lipid media with the TBARS method and those obtained in the aqueousmedia (peroxynitrite scavenging activity, TEAC and FRAP methods.

  20. Interaction of yeasts with the products resulting from the condensation reaction between (+)-catechin and acetaldehyde.

    Science.gov (United States)

    Lopez-Toledano, Azahara; Villaño-Valencia, Debora; Mayen, Manuel; Merida, Julieta; Medina, Manuel

    2004-04-21

    The condensation reaction between (+)-catechin and acetaldehyde was studied in model solutions in the presence and absence yeasts in order to evaluate its contribution to color changes in fermented drinks such as white wine. On the basis of the results, the yeasts retain the oligomers produced in the reaction, their retention ability increasing for higher polymerization degrees. As a result, the color of model solutions, measured as the absorbance at 420 nm, was found to decrease after the addition of yeasts. On the other hand, the yeasts exhibited no inhibitory effect on the condensation reaction, which took place at the same rate in their presence and absence. At acidity levels and reactant concentrations similar to those in wine, with acetaldehyde in high concentration as it is present in sherry wines, the reaction was found to occur very slowly. Taking into account that Yeasts are present during most of the winemaking process; consequently, they retain oligomers, and the studied reaction could mainly contribute to the alteration of the color of white wine after bottling. PMID:15080649

  1. Effect of green tea catechins on gastric mucosal dysplasia in insulin-gastrin mice.

    Science.gov (United States)

    Ohno, Takashi; Ohtani, Masahiro; Suto, Hiroyuki; Ohta, Makoto; Imamura, Yoshiaki; Matsuda, Hidetaka; Hiramatsu, Katsushi; Nemoto, Tomoyuki; Nakamoto, Yasunari

    2016-06-01

    Green tea catechins (GTCs) have been implicated in various physiological effects, including anti-carcinogenic activities. In the present study, we evaluated the effects of GTCs specifically on the development of gastritis and pre-malignant lesions in insulin-gastrin mice. Nine-week-old male INS-GAS mice (n=38) were supplemented with GTCs for 4 and 28 weeks, and their body weights, serum gastrin levels, histopathology and pro-inflammatory cytokine levels in gastric tissue and mucosal cell proliferation were monitored. Body weights of the GTC-treated mice were significantly lower than those of the untreated controls (P≤0.05). Serum gastrin levels were suppressed at the age of 37-weeks (P≤0.05). The histopathological scores indicated that the extent of dysplasia was significantly diminished (P≤0.05), although GTC supplementation did not affect the inflammation scores. The messenger RNA levels of interferon (IFN)-γ were significantly reduced at the age of 13 weeks (P≤0.05), although the changes did not reach statistical significance at the age of 37 weeks (P=0.056). The labeling index of Ki-67 immunohistochemistry was significantly decreased (P≤0.05). These results demonstrated that GTCs may play a protective role in the development of gastritis and pre-malignant lesions via an IFN-γ, gastrin, and mucosal cell proliferation-dependent mechanism in this rodent model and potentially in humans. PMID:27035882

  2. Spectroscopic and docking studies of the binding of two stereoisomeric antioxidant catechins to serum albumins

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Durba; Dutta, Samrajnee; Maity, Shyam Sundar [Department of Chemistry, Presidency University, Kolkata 700 073 (India); Ghosh, Sanjib, E-mail: sanjibg@cal2.vsnl.net.in [Department of Chemistry, Presidency University, Kolkata 700 073 (India); Singha Roy, Atanu; Ghosh, Kalyan Sundar [Department of Chemistry, Indian Institute of Technology, Kharagpur 721 302 (India); Dasgupta, Swagata, E-mail: swagata@chem.iitkgp.ernet.in [Department of Chemistry, Indian Institute of Technology, Kharagpur 721 302 (India)

    2012-06-15

    The interactions of two stereoisomeric antioxidant flavonoids, catechin (C) and epicatechin (EC) with bovine serum albumin (BSA) and human serum albumin (HSA), have been investigated by steady state and time resolved fluorescence, phosphorescence, circular dichroism (CD), FTIR and protein-ligand docking studies. The steady-state fluorescence studies indicate a single binding site for both the ligands. FTIR spectra suggest that in both the albumins, C and EC stabilize the {alpha}-helix at the cost of a corresponding loss in the {beta}-sheet structure. CD studies have been carried out using ({+-})C, and both the epimers (+)C and (-)C. The low temperature phosphorescence and protein-ligand [(+), (-) and ({+-}) forms of C and EC] docking studies indicate that the ligands bind in the proximity of Trp 134 of BSA and Trp 214 of HSA, thereby changing their solvent accessible surface areas (ASA). Asn 158 and Glu 130 side chains are found to be within the hydrogen bonding distance from the phenolic -OH groups of C and EC in the case of BSA complex. C and EC are located within the binding pocket of sub-domain IIa of HSA. - Highlights: Black-Right-Pointing-Pointer Binding of two biologically important stereoisomeric antioxidants. Black-Right-Pointing-Pointer To find a significant role in pharmacology. Black-Right-Pointing-Pointer To find the conformational changes of the protein leading to the perturbation of Trp residues.

  3. Graphene flakes enhance the detection of TiO2-enriched catechins by SALDI-MS after microwave-assisted enrichment.

    Science.gov (United States)

    Juang, Yu-Min; Chien, Han-Ju; Chen, Chao-Jung; Lai, Chien-Chen

    2016-06-01

    In this study, we describe a novel method for the rapid detection of catechins in tea leaves using surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The method involves incubating catechins in a mixture of titanium dioxide (TiO2) nanoparticles and graphene flakes (GF) and then subjecting the mixture to microwave irradiation to facilitate the enrichment of analytes. In this approach, TiO2 nanoparticles serve as probes to enrich catechins while GF serve to increase the desorption/ionization efficiency. The use of the TiO2-GF mixture as matrix provides a number of advantages over TiO2 nanoparticles alone, including higher desorption/ionization efficiency, enhanced analyte enrichment and reduced run time (less 10min). We demonstrate that the addition of GF to nanoparticles of TiO2 improves the detection of catechins by SALDI-MS. At a signal-to-noise ratio of 3, the limits of detection were 0.04pmole for (+)-catechin (C), 0.17pmole for (-)-epigallocatechin (EGC), 0.35pmole for (-)-epicatechin gallate (ECG), and 0.50pmole for (-)-epigallocatechin gallate (EGCG). This method was further applied to determine the catechin content in several tea samples and the results showed good shot-to-shot and sample-to-sample reproducibility (less than 10% and 13%, respectively) as well as good quantitative linearity for the four analytes (R(2)>0.995). The precision calculated as percent relative standard derivation (%RSD), ranged from 3.6% to 12.4%. Overall, we show that this method is a sensitive, simple and high-throughput technique for the detection of catechins in tea. PMID:27130126

  4. A tea catechin, epigallocatechin-3-gallate, is a unique modulator of the farnesoid X receptor

    International Nuclear Information System (INIS)

    Farnesoid X receptor (FXR) is a ligand-activated nuclear receptor and serves as a key regulator to maintain health of the liver and intestine. Bile acids are endogenous ligands of FXR, and there are increasing efforts to identify FXR modulators to serve as biological probes and/or pharmaceutical agents. Natural FXR ligands isolated from plants may serve as models to synthesize novel FXR modulators. In this study, we demonstrated that epigallocatechin-3-gallate (EGCG), a major tea catechin, specifically and dose-dependently activates FXR. In addition, EGCG induced FXR target gene expression in vitro. Surprisingly, in a co-activator (SRC2) recruitment assay, we found that EGCG does not recruit SRC2 to FXR, but it dose-dependently inhibits recruitment of SRC2 to FXR (IC50, 1 μM) by GW6064, which is a potent FXR synthetic ligand. In addition, EGCG suppressed FXR target gene expression induced by either GW4064 or chenodeoxycholic acid in vitro. Furthermore, wild-type and FXR knockout mice treated with an acute dose of EGCG had induced mRNA expression in a subset of FXR target genes in the intestine but not in the liver. In conclusion, EGCG is a unique modulator of FXR in the intestine and may serve as an important model for future development of FXR modulators. -- Highlights: ► Epigallocatechin-3-gallate (EGCG) is a unique farnesoid X receptor (FXR) modulator. ► EGCG activates FXR by itself, but inhibits FXR transactivation by other agonists. ► Low concentration of EGCG activates FXR in mouse intestine but not liver. ► EGCG activates FXR to induce a subset of FXR target genes in mouse intestine.

  5. A tea catechin, epigallocatechin-3-gallate, is a unique modulator of the farnesoid X receptor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guodong [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Department of Abdominal Surgery, Cancer treatment center, Fourth Affiliated Hospital of Harbin Medical University, Harbin (China); Lin, Wenwei [Department of Chemical Biology and Therapeutics, St. Jude Children' s Research Hospital, Memphis, TN (United States); Araya, Juan J. [Department of Medicinal Chemistry, University of Kansas, Lawrence, KS (United States); Chen, Taosheng [Department of Chemical Biology and Therapeutics, St. Jude Children' s Research Hospital, Memphis, TN (United States); Timmermann, Barbara N. [Department of Medicinal Chemistry, University of Kansas, Lawrence, KS (United States); Guo, Grace L., E-mail: lguo@kumc.edu [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2012-01-15

    Farnesoid X receptor (FXR) is a ligand-activated nuclear receptor and serves as a key regulator to maintain health of the liver and intestine. Bile acids are endogenous ligands of FXR, and there are increasing efforts to identify FXR modulators to serve as biological probes and/or pharmaceutical agents. Natural FXR ligands isolated from plants may serve as models to synthesize novel FXR modulators. In this study, we demonstrated that epigallocatechin-3-gallate (EGCG), a major tea catechin, specifically and dose-dependently activates FXR. In addition, EGCG induced FXR target gene expression in vitro. Surprisingly, in a co-activator (SRC2) recruitment assay, we found that EGCG does not recruit SRC2 to FXR, but it dose-dependently inhibits recruitment of SRC2 to FXR (IC{sub 50}, 1 μM) by GW6064, which is a potent FXR synthetic ligand. In addition, EGCG suppressed FXR target gene expression induced by either GW4064 or chenodeoxycholic acid in vitro. Furthermore, wild-type and FXR knockout mice treated with an acute dose of EGCG had induced mRNA expression in a subset of FXR target genes in the intestine but not in the liver. In conclusion, EGCG is a unique modulator of FXR in the intestine and may serve as an important model for future development of FXR modulators. -- Highlights: ► Epigallocatechin-3-gallate (EGCG) is a unique farnesoid X receptor (FXR) modulator. ► EGCG activates FXR by itself, but inhibits FXR transactivation by other agonists. ► Low concentration of EGCG activates FXR in mouse intestine but not liver. ► EGCG activates FXR to induce a subset of FXR target genes in mouse intestine.

  6. In vitro transdermal delivery of caffeine, theobromine, theophylline and catechin from extract of Guarana, Paullinia Cupana.

    Science.gov (United States)

    Heard, Charles M; Johnson, Sarah; Moss, Gary; Thomas, Chris P

    2006-07-01

    Extracts of guarana (Paullinia cupana) feature as putatively stimulating ingredients in a number of foods, drinks and dietary/herbal supplements. The objective of this work was to investigate in vitro the transdermal delivery of the major pharmacologically active compounds contained in guarana extract. Saturated solutions of guarana were prepared in polyethylene glycol 400 (PEG400), propylene glycol (PG) and H(2)O at 32 degrees C. Guarana extract was also formulated in Duro-tak 2287 transdermal adhesive in a range of concentrations and the diffusional release was determined in addition to adhesive properties. Transdermal delivery across full thickness pig ear skin was investigated in vitro using Franz-type diffusion cells, with reverse-phase HPLC being used for the quantification of the permeation of theobromine (TB), theophylline (TP), (+)-catechin (C) and caffeine (CF). Based upon a combination of release and adhesive property data a patch containing 5.55 mg guarana extract cm(-2) was deemed optimal. The general trend for the delivery of the 4 analytes was: water >5.55 mg cm(-2) patch approximately PG>PEG400. For CF the greatest steady state flux was obtained from the water vehicle: 19 microg cm(-2)h(-1), with approximately 420 microg cm(-2) permeating after 24h. This was some 6x times more than from the drug-in-adhesive patch and 10x greater than PG, a well-known penetration enhancer, and 50x that of the 'regular' excipient PEG400. A water vehicle also provided the greatest delivery of TB (0.45 microg cm(-2) h(-1)), TP (0.022 microg cm(-2) h(-1)), and C (0.10 microg cm(-2) h(-1)). An inverse relationship was noted between lipophilicity and k(p) in each vehicle. The simultaneous transdermal delivery of the major actives of guarana was established, with permeation rates being highly concentration and vehicle dependent. PMID:16600539

  7. Simple isocratic method for simultaneous determination of caffeine and catechins in tea products by HPLC.

    Science.gov (United States)

    Fernando, Chamira Dilanka; Soysa, Preethi

    2016-01-01

    Tea is a popular beverage almost all over the world. Many studies show that tea consumption is closely associated with positive health impact. Most of the HPLC methods used for the determination of tea constituents include gradient elution systems which involve expensive instrumentation. The objective of this study was to develop a simple, rapid precise and low cost HPLC method for the separation and quantification of catechins and caffeine in tea (Camellia sinensis). The method utilizes a phenyl column (2.1 × 150 mm) with a UV-detector (280 nm) where excellent chromatographic separation of tea components i.e. gallic acid (GA), caffeine (Caf), epicatechin (EC) and (-)-epigallocatechin gallate (EGCG) was achieved. The isocratic elution system of acetonitrile, glacial acetic acid and deionized water (8:1:91 v/v/v) at a flow rate of 0.5 mL/min was involved. This method produced excellent accuracy and precision. Within run and between run precision was less than 7.5 %. The equations for calibration curves were y = 0.117 (±0.010)x + 0.173 (±0.024), y = 0.100 (±0.003)x + 0.045 (±0.019), y = 0.016 (±0.001)x + 0.006 (±0.004), y = 0.025 (±0.001)x-0.025 (±0.007) for GA, Caf, EC and EGCG respectively. The method validation parameters prove that the method is efficient, a simple and adequate for the quantitative determination of principal components in tea samples. PMID:27429880

  8. Inhibition of green tea and the catechins against 1-deoxy-d-xylulose 5-phosphate reductoisomerase, the key enzyme of the MEP terpenoid biosynthetic pathway.

    Science.gov (United States)

    Hui, Xian; Liu, Hui; Tian, Fang-Lin; Li, Fei-Fei; Li, Heng; Gao, Wen-Yun

    2016-09-01

    1-Deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) is the first committed enzyme in the MEP terpenoid biosynthetic pathway and also a validated antimicrobial target. Green tea which is rich in polyphenolic components such as the catechins, possesses a plenty of pharmacological activities, in particular an antibacterial effect. To uncover the antibacterial mechanism of green tea and to seek new DXR inhibitors from natural sources, the DXR inhibitory activity of green tea and its main antimicrobial catechins were investigated in this study. The results show that the raw extract of green tea and its ethyl acetate fraction are able to suppress DXR activity explicitly. Further determination of the DXR inhibitory capacity of eight catechin compounds demonstrates that the most active compound is gallocatechin gallate that is able to inhibit around 50% activity of DXR at 25μM. Based on these data, the primary structure-activity relationship of the catechins against DXR is discussed. This study would be very helpful to elucidate the antimicrobial mechanism of green tea and the catechins and also would be very useful to direct the rational utilization of them as food additives. PMID:27439219

  9. Simultaneous determination of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in standard reference material baking chocolate 2384, cocoa, cocoa beans, and cocoa butter.

    Science.gov (United States)

    Risner, Charles H

    2008-01-01

    A reverse-phase liquid chromatography analysis is used to access the quantity of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in Standard Reference Material 2384 Baking Chocolate, cocoa, cocoa beans, and cocoa butter using water or a portion of the mobile phase as the extract. The procedure requires minimal sample preparation. Theobromine, (+)-catechin, caffeine, and (-)-epicatechin are detected by UV absorption at 273 nm after separation using a 0.3% acetic acid-methanol gradient (volume fractions) and quantified using external standards. The limit of detection for theobromine, (+)-catechin, caffeine, and (-)-epicatechin averages 0.08, 0.06, 0.06, and 0.06 microg/mL, respectively. The method when applied to Standard Reference Material 2384 Baking Chocolate; baking chocolate reference material yields results that compare to two different, separate procedures. Theobromine ranges from 26000 mg/kg in cocoa to 140 mg/kg in cocoa butter; (+)-catechin from 1800 mg/kg in cocoa to below detection limits of < 32 mg/kg in cocoa butter; caffeine from 2400 mg/kg in cocoa to 400 mg/kg in cocoa butter, and (-)-epicatechin from 3200 mg/kg in cocoa to BDL, < 27 mg/kg, in cocoa butter. The mean recoveries from cocoa are 102.4 +/- 0.6% for theobromine, 100.0 +/- 0.6 for (+)-catechin, 96.2 +/- 2.1 for caffeine, and 106.2 +/- 1.7 for (-)-epicatechin. PMID:19007497

  10. Healthcare of tea catechins and its mechanism%儿茶素类的保健作用及机制

    Institute of Scientific and Technical Information of China (English)

    龙丹; 江和源; 薛金金; 王伟伟; 张建勇; 王岩

    2013-01-01

      Tea is a healthy beverage which is very popular around the world in the 21st century. Consider-able papers had showed that many healthy effects of tea were associated with its beneficial constituents espe-cially tea catechins. Tea catechins, with various medical and healthy functions and some special properties, are not only applied to orally ingested products such as dietary supplements, healthy food, healthy drinks, but also used in cosmetics, daily chemical products for external application, and indicated a potential market in the fu-ture. This paper reviewed the major healthy functions and their possible mechanisms of tea catechins.%  茶是二十一世纪风靡全球的健康饮料。茶叶中含有多种保健功能成分,尤其是儿茶素类物质。儿茶素具有诸多医疗保健功能和一些特殊性质,不仅被应用于经口服的膳食补充剂、保健食品、保健饮料等产品,还应用于化妆品、日化用品等外用型的健康产品,具有良好的市场开发潜力。本文综述了内服和外用两种方式下儿茶素类物质的保健作用及其作用机制。

  11. Transformation of tea catechins and flavonoid glycosides by treatment with Japanese post-fermented tea acetone powder

    OpenAIRE

    Tanaka, Takashi; Umeki, Hirotaka; NAGAI, SACHI; Shii, Takuya; Matsuo, Yosuke; Kouno, Isao

    2012-01-01

    Japanese post-fermented teas are produced by a combination of aerobic and anaerobic microbial fermentation of the leaves of tea plant. Recently, it was revealed that tea products contain characteristic polyphenols identical to the tea catechin metabolites produced by mammalian intestinal bacteria, such as (2S)-1-(3′,4′,5′-trihydroxyphenyl)-3-(2″,4″,6″-trihydroxyphenyl)-propan-2-ol (EGC-M1). In the present study, degradation of epigallocatechin-3-O-gallate (EGCg) and epigallocatechin (EGC) wit...

  12. Primary Cancer Prevention by Green Tea, and Tertiary Cancer Prevention by the Combination of Green Tea Catechins and Anticancer Compounds

    OpenAIRE

    Fujiki, Hirota; Sueoka, Eisaburo; Watanabe, Tatsuro; Suganuma, Masami

    2015-01-01

    Green tea is a daily beverage, a non-oxidized non-fermented product containing at least four green tea catechins. Considering our first results when repeated applications of (-)-epigallocatechin gallate (EGCG) prevented tumor promotion in mouse skin, we have continued to look at green tea as a possible cancer preventive agent. 1) The 10-year prospective cohort study by Drs. K. Nakachi and K. Imai revealed that drinking 10 Japanese-size cups (120 mL/cup) of green tea per day delayed cancer ons...

  13. Determination of Phenolic and Antioxidant Properties in Tea and Spent Tea Under Various Extraction Method and Determination of Catechins, Caffeine and Gallic Acid by HPLC

    Directory of Open Access Journals (Sweden)

    Nurul Nadiah binti Ismail

    2015-01-01

    Full Text Available Tea (Camellia sinensis L. contain high phenolic compounds and antioxidant elements, while spent teas originating as the main byproduct of beverage tea manufacturestill contain some level of antioxidant elements. The purpose of the present study is to compare the effect of different extraction condition and to determine the chemical compound present in black tea (BT, oolong tea (OT, green tea (GT, spent black tea (SBT, spent oolong tea (SOT and spent green tea (SGT. Theextraction experiment were carried out by the conventional solid-liquid method, using boiling water (100ºC and 50% ethanol concentration, with extraction period of 5 minutes. The influence of these extraction methods on the content of total phenolic compounds and antioxidant activities of the extracts were evaluated. Flavanoid, gallic acid, caffeine and four catechins (catechin (C, gallocatechin (GCG, epicatechin (EC and epigallocatechin (EGC were found in all of the extracts and were quantified by utilizing High Performance Liquid Chromatography (HPLC analysis tool. GT extraction using 50% ethanol concentration was found to be the most suitable method to produce an extract with high content of phenolic compounds ( 186.83 mg GAE/100 g tea and high antioxidant activities (FRAP of 3814.29 μmol Fe(II/g, simultaneously. The results shown that GT had higher total flavanoids value at 347.67 mg CEQ/g followed by OT (295.00 mg CEQ/g and than the BT (187.33 mg CEQ/g. The analytical HPLC results obtained also indicated that GT contained higher amount of catechins than OT, BT, SGT, SOT and SBT due to fermentation process during the tea manufacturing, which reduces the levels of catechin significantly. All four catechins were detected in GT. However, epicatechin, and gallocatecin gallate are the major catechin present in SGT.

  14. Enhancement of photoprotection potential of catechin loaded nanoemulsion gel against UVA induced oxidative stress.

    Science.gov (United States)

    Harwansh, Ranjit K; Mukherjee, Pulok K; Kar, Amit; Bahadur, Shiv; Al-Dhabi, Naif Abdullah; Duraipandiyan, V

    2016-07-01

    The present study was aimed to develop a catechin (CA) loaded nanoemulsion based nano-gel for the protection of skin against ultraviolet radiation (UV) induced photo-damage and to ensure its enhanced skin permeability as well as bioavailability through transdermal route. The optimized nanoemulsion (CA-NE4) was prepared by spontaneous nano-emulsification method. It was composed of oil (ethyl oleate), Smix [surfactant (span 80) and co-surfactant (transcutol CG)] and aqueous system in an appropriate ratio of 15:62:23% w/w respectively. The CA-NE4 was characterized through assessment of droplet size, zeta potential, refractive index, transmission electron microscopy (TEM), UV, high performance thin layer chromatography (HPTLC) and Fourier transform infrared spectroscopy (FTIR) analysis. The average droplet size and zeta potential of CA-NE4 were found to be 98.6±1.01nm and -27.3±0.20mV respectively. The enhanced skin permeability was better with CA-NE4 based nano-gel (CA-NG4) [96.62%] compared to conventional gel (CA-CG) [53.01%] for a period of 24h. The enhanced % relative bioavailability (F) of CA (894.73), Cmax (93.79±6.19ngmL(-1)), AUC0-t∞ (2653.99±515.02nghmL(-1)) and Tmax (12.05±0.02h) was significantly obtained with CA-NG4 as compared to oral suspension for extended periods (72h). CA-NG4 could improve the level of cutaneous antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) and reduce the level of thiobarbituric acid reactive substances (TBRAS) against oxidative stress induced by UVA. Nano-gel formulation of CA showed sustained release profile and enhanced photoprotection potential due to its improved permeability as well as bioavailability (Pstrategy for decreasing UV-induced oxidative damage in the skin tissues. PMID:27167597

  15. Catechin-based procyanidins from Peumus boldus Mol. aqueous extract inhibit Helicobacter pylori urease and adherence to adenocarcinoma gastric cells.

    Science.gov (United States)

    Pastene, Edgar; Parada, Víctor; Avello, Marcia; Ruiz, Antonieta; García, Apolinaria

    2014-11-01

    In this work, the anti-Helicobacter pylori effect of an aqueous extract from dried leaves of Peumus boldus Mol. (Monimiaceae) was evaluated. This extract displayed high inhibitory activity against H. pylori urease. Therefore, in order to clarify the type of substances responsible for such effect, a bioassay-guided fractionation strategy was carried out. The active compounds in the fractions were characterized through different chromatographic methods (RP-HPLC; HILIC-HPLC). The fraction named F5 (mDP = 7.8) from aqueous extract was the most active against H. pylori urease with an IC50  = 15.9 µg gallic acid equivalents (GAE)/mL. HPLC analysis evidenced that F5 was composed mainly by catechin-derived proanthocyanidins (LC-MS and phloroglucinolysis). The anti-adherent effect of boldo was assessed by co-culture of H. pylori and AGS cells. Both the aqueous extract and F5 showed an anti-adherent effect in a concentration-dependent manner. An 89.3% of inhibition was reached at 2.0 mg GAE/mL of boldo extract. In conjunction, our results suggest that boldo extract has a potent anti-urease activity and anti-adherent effect against H. pylori, properties directly linked with the presence of catechin-derived proanthocyanidins. PMID:24853276

  16. Steroid hormones analysis with surface-assisted laser desorption/ionization mass spectrometry using catechin-modified titanium dioxide nanoparticles.

    Science.gov (United States)

    Chiu, Tai-Chia

    2011-10-30

    This paper describes the application of catechin-modified titanium dioxide nanoparticles (TiO(2) NPs) as matrices to analyze four steroid hormones by surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The catechin-modified TiO(2) NPs have high absorbance at 337 nm and are effective SALDI matrices when using a nitrogen laser. Four test steroid hormones-cortisone, hydrocortisone, progesterone, and testosterone-were directly analyzed by SALDI-MS. The limits of detection at a signal-to-noise ratio of 3 for cortisone, hydrocortisone, progesterone, and testosterone were 1.62, 0.70, 0.66, and 0.23 μM, respectively. This approach provides good quantitative linearity for the four analytes (R(2)>0.986) with good reproducibility (the shot-to-shot and batch-to-batch variations for the four analytes were less than 10% and 15%, respectively). We validated the practicality of this approach-considering its advantages in sensitivity, repeatability, rapidity, and simplicity-through the analysis of testosterone in a urine sample. PMID:22063559

  17. Protection of ascorbic acid from copper(II)-catalyzed oxidative degradation in the presence of flavonoids: quercetin, catechin and morin.

    Science.gov (United States)

    Beker, Bilge Yildoğan; Sönmezoğlu, Inci; Imer, Filiz; Apak, Reşat

    2011-08-01

    Protection of ascorbic acid (AA) (vitamin C) from Cu(II)-catalyzed autoxidation is an important aspect of antioxidant chemistry. The autoxidation of AA in the absence and presence of Cu(II) ions was investigated in aerated solution at room temperature and I = 0.1 ionic strength (KNO(3)); the effects of three different flavonoids of similar structure (quercetin, morin and catechin) and their mixtures on the AA system were studied. The concentration of unoxidized AA remaining in solution was measured with the modified cupric ion reducing antioxidant capacity spectrophotometric method. The Cu(II)-catalyzed oxidation at pH 4.5 followed first-order kinetics with respect to AA concentration. Catalytic autoxidation of AA was inhibited to a greater extent by stable quercetin and morin complexes of Cu(II) than by catechin complex. The inhibitive effectiveness order of mixtures gives information about possible synergistic or antagonistic combinations of flavonoid antioxidants, which should be further confirmed with other antioxidant tests. PMID:21391791

  18. Beta-Carotene chemical stability in nanoemulsions was improved by stabilized with Beta-Lactoglobulin-Catechin conjugates through free radical method

    Science.gov (United States)

    Beta-lactoglobulin (BLG)-catechin conjugates were prepared by a free radical method and investigated with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), electrospray ionization-mass spectrometry (ESI-MS), and far-UV circular dichroism (CD). Covalent binding between BLG and cat...

  19. The characterization of caffeine and nine individual catechins in the leaves of green tea (Camellia sinensis L.) by near-infrared reflectance spectroscopy.

    Science.gov (United States)

    Lee, Min-Seuk; Hwang, Young-Sun; Lee, Jinwook; Choung, Myoung-Gun

    2014-09-01

    Near-infrared reflectance spectroscopy (NIRS) was used to determine the contents of caffeine and nine individual catechins in tea leaves. A total of 665 samples were scanned by NIRS, and also by high performance liquid chromatography coupled to a diode array detector to determine the contents of caffeine and nine individual catechins. The calibration models for caffeine, EGC, C, EGCG, EC, ECG, and total catechins had high r(2) (more than 0.90) and RSP (the ratio of standard deviation of reference data to SEP(C) in the external validation set) values (more than 4.1), indicating a good correlation between reference values and NIRS predicted values. In contrast, the calibration models of GC and EGCG-3Me had low r(2) and RSP values (below 0.8 and 2.0). Therefore, these results suggest that NIRS could be applied for the rapid determination of the contents of caffeine, EGC, C, EGCG, EC, ECG, and total catechins in tea leaves for breeding programs that develop high-quality tea plants. PMID:24731354

  20. Sulforaphane, quercetin and catechins complement each other in elimination of advanced pancreatic cancer by miR-let-7 induction and K-ras inhibition

    Science.gov (United States)

    APPARI, MAHESH; BABU, KAMESH R.; KACZOROWSKI, ADAM; GROSS, WOLFGANG; HERR, INGRID

    2014-01-01

    Pancreatic ductal adenocarcinoma (PDA) has the worst prognosis of all malignancies, and current therapeutic options do not target cancer stem cells (CSCs), which may be the reason for the extreme aggressiveness. The dietary agents sulforaphane and quercetin enriched e.g., in broccoli, and the main and best studied green tea catechin EGCG hold promise as anti-CSC agents in PDA. We examined the efficacy of additional catechins and the combination of these bioactive agents to stem cell features and miRNA signaling. Two established and one primary PDA cell line and non-malignant pancreatic ductal cells were used. Whereas each agent strongly inhibited colony formation, the catechins ECG and CG were more effective than EGCG. A mixture of green tea catechins (GTCs) significantly inhibited viability, migration, expression of MMP-2 and -9, ALDH1 activity, colony and spheroid formation and induced apoptosis, but the combination of GTCs with sulforaphane or quercetin was superior. Following treatment with bioactive agents, the expression of miR-let7-a was specifically induced in cancer cells but not in normal cells and it was associated with K-ras inhibition. These data demonstrate that sulforaphane, quercetin and GTC complement each other in inhibition of PDA progression by induction of miR-let7-a and inhibition of K-ras. PMID:25017900

  1. Synthesis of (2R, 3R)-epigallocatechin-3-O-(4-hydroxybenzoate), a novel catechin from Cistus salvifolius, and evaluation of its proteasome inhibitory activities

    OpenAIRE

    Osanai, Kumi; HUO, CONGDE; Landis-Piwowar, Kristin R.; Dou, Q. Ping; CHAN, TAK HANG

    2007-01-01

    The total and semi syntheses of (2R, 3R)-epigallocatechin-3-O-(4-hydroxybenzoate), a novel catechin from Cistus salvifolius, was accomplished. The proteasome inhibition and cytotoxic activities of the synthetic compound and its acetyl derivative were studied and compared with (2R, 3R)-epigallocatechin-3-gallate (EGCG), the active component from green tea.

  2. Synthesis of (2R, 3R)-epigallocatechin-3-O-(4-hydroxybenzoate), a novel catechin from Cistus salvifolius, and evaluation of its proteasome inhibitory activities.

    Science.gov (United States)

    Osanai, Kumi; Huo, Congde; Landis-Piwowar, Kristin R; Dou, Q Ping; Chan, Tak Hang

    2007-08-01

    The total and semi syntheses of (2R, 3R)-epigallocatechin-3-O-(4-hydroxybenzoate), a novel catechin from Cistus salvifolius, was accomplished. The proteasome inhibition and cytotoxic activities of the synthetic compound and its acetyl derivative were studied and compared with (2R, 3R)-epigallocatechin-3-gallate (EGCG), the active component from green tea. PMID:21152270

  3. Level of Catechin, Myricetin, Quercetin and Isoquercitrin in Buckwheat (Fagopyrum esculentum Moench), Changes of Their Levels during Vegetation and Their Effect on The Growth of Selected Weeds

    Czech Academy of Sciences Publication Activity Database

    Kalinová, J.; Vrchotová, Naděžda

    2009-01-01

    Roč. 57, č. 7 (2009), s. 2719-2725. ISSN 0021-8561 Institutional research plan: CEZ:AV0Z60870520 Keywords : Allelopathy * buckwheat * catechin * quercetin * myricetin * weed Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.469, year: 2009

  4. Preparative isolation of monomer catechins and oligomer procyanidin fractions from grape seed extracts by high-speed counter-current chromatography

    Directory of Open Access Journals (Sweden)

    Shuting Zhang

    2014-01-01

    Full Text Available In this paper, monomer (+-catechin; (--epicatechin and (--epicatechin-3-o-gallate, three oligomeric procyanidin fractions (OPCs and one polymeric procyanidin fractions (PPCs were successfully separated and isolated from grape seed extracts using semi-preparative TBE-300 B high-speed counter-current chromatography (HSCCC. For their separation in monomer (+-catechin; (--epicatechin and (--epicatechin 3-O-gallate, hexane/ethyl acetate/water (1:10: 10, v/v/v was selected as solvent system. For separation of OPCs and PPCs, solvent system ethyl acetate/water (1:1, v/v was selected. Compositional data and mean polymerization degrees of OPCs were determined by phloroglucinolysis method. The purity of each fraction obtained; monomer (+-catechin (C, (--epicatechin (EC and (--epicatechin-3-o-gallate (ECG, verified by UPLC, was 98%, 82% and 71%, respectively. The mean polymerization degrees of the three OPCs fractions were respectively 2.842, 3.521, 4.475. As compared with traditional separation methods for catechins and OPCs, HSCCC has shown to be a powerful and efficient technique for large-scale isolation of these compounds.

  5. Enhanced uptake and transport of (+-catechin and (--epigallocatechin gallate in niosomal formulation by human intestinal Caco-2 cells

    Directory of Open Access Journals (Sweden)

    Song Q

    2014-05-01

    Full Text Available Qinxin Song,1–3 Danhui Li,3 Yongzhi Zhou,3 Jie Yang,1 Wanqi Yang,1 Guohua Zhou,2 Jingyuan Wen31Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, School of Pharmacy, China Pharmaceutical University, 2Department of Pharmacology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, People’s Republic of China; 3School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New ZealandAbstract: The aim of this study was to evaluate (+-catechin and (−-epigallocatechin gallate (EGCG cellular uptake and transport across human intestinal Caco-2 cell monolayer in both the absence and presence of niosomal carrier in variable conditions. The effect of free drugs and drug-loaded niosomes on the growth of Caco-2 cells was studied. The effects of time, temperature, and concentration on drug cellular uptake in the absence or presence of its niosomal delivery systems were investigated. The intestinal epithelial membrane transport of the drug-loaded niosomes was examined using the monolayer of the human Caco-2 cells. The kinetics of transport, and the effect of temperature, adenosine triphosphate inhibitor, permeability glycoprotein inhibitor, multidrug resistance-associated protein 2 inhibitor, and the absorption enhancer on transport mechanism were investigated. It was found that the uptake of catechin, EGCG, and their niosomes by Caco-2 cells was 1.22±0.16, 0.90±0.14, 3.25±0.37, and 1.92±0.22 µg/mg protein, respectively (n=3. The apparent permeability coefficient values of catechin, EGCG, and their niosomes were 1.68±0.16, 0.88±0.09, 2.39±0.31, and 1.42±0.24 cm/second (n=3 at 37°C, respectively. The transport was temperature- and energy-dependent. The inhibitors of permeability glycoprotein and multidrug resistance-associated protein 2 and the absorption enhancer significantly enhanced the uptake amount. Compared with the free drugs, niosomal formulation

  6. Bioavailability of catechins from guaraná (Paullinia cupana) and its effect on antioxidant enzymes and other oxidative stress markers in healthy human subjects.

    Science.gov (United States)

    Yonekura, Lina; Martins, Carolina Aguiar; Sampaio, Geni Rodrigues; Monteiro, Marcela Piedade; César, Luiz Antônio Machado; Mioto, Bruno Mahler; Mori, Clara Satsuki; Mendes, Thaíse Maria Nogueira; Ribeiro, Marcelo Lima; Arçari, Demetrius Paiva; Torres, Elizabeth Aparecida Ferraz da Silva

    2016-07-13

    We assessed the effects of guaraná (Paullinia cupana) consumption on plasma catechins, erythrocyte antioxidant enzyme activity (superoxide dismutase, catalase and glutathione peroxidase) and biomarkers of oxidative stress (ex vivo LDL oxidation, plasma total antioxidant status and ORAC, and lymphocyte single cell gel electrophoresis) in healthy overweight subjects. Twelve participants completed a 15-day run-in period followed by a 15-day intervention with a daily intake of 3 g guaraná seed powder containing 90 mg (+)-catechin and 60 mg (-)-epicatechin. Blood samples were taken on the first and last day of the intervention period, fasting and 1 h post-dose. The administration of guaraná increased plasma ORAC, while reducing ex vivo LDL oxidation (only in the first study day) and hydrogen peroxide-induced DNA damage in lymphocytes, at 1 h post-dose. Plasma catechin (0.38 ± 0.12 and 0.44 ± 0.18 nmol mL(-1)), epicatechin (0.59 ± 0.18 and 0.64 ± 0.25 nmol mL(-1)) and their methylated metabolites were observed at 1 h post-dose but were almost negligible after overnight fasting. The activities of catalase (in both study days) and glutathione peroxidase (in the last intervention day) increased at 1 h post-dose. Furthermore, the activity of both enzymes remained higher than the basal levels in overnight-fasting individuals on the last intervention day, suggesting a prolonged effect of guaraná that continues even after plasma catechin clearance. In conclusion, guaraná catechins are bioavailable and contribute to reduce the oxidative stress of clinically healthy individuals, by direct antioxidant action of the absorbed phytochemicals and up-regulation of antioxidant/detoxifying enzymes. PMID:27302304

  7. Epimerization of Green Tea Catechins During Brewing Does Not Affect the Ability to Poison Human Type II Topoisomerases

    Science.gov (United States)

    Timmel, M. Anne; Byl, Jo Ann W.; Osheroff, Neil

    2013-01-01

    (−)-Epigallocatechin gallate (EGCG) is the most abundant and biologically active polyphenol in green tea (Camellia sinensis) leaves and many of its cellular effects are consistent with its actions as a topoisomerase II poison. In contrast to genistein and several other related bioflavonoids that act as interfacial poisons, EGCG was the first bioflavonoid shown to act as a covalent topoisomerase II poison. Although studies routinely examine the effects of dietary phytochemicals on enzyme and cellular systems, they often fail to consider that many compounds are altered during cooking or cellular metabolism. To this point, the majority of EGCG (and related catechins) in green tea leaves is epimerized during the brewing process. Epimerization reverses the stereochemistry of the bond that bridges the B- and C-rings, and converts EGCG to (−)-gallocatechin gallate (GCG). Consequently, a significant proportion of EGCG that is ingested during the consumption of green tea is actually GCG. Therefore, the effects of GCG and related epimerized green tea catechins on human topoisomerase IIα and IIβ were characterized. GCG increased levels of DNA cleavage mediated by both enzyme isoforms with an activity that was similar to that of EGCG. GCG acted primarily by inhibiting the ability of topoisomerase IIα and IIβ to ligate cleaved DNA. Several lines of evidence indicate that GCG functions as a covalent topoisomerase II poison that adducts the enzyme. Finally, epimerization did not affect the reactivity of the chemical substituents (the three hydroxyl groups on the Bring) that were required for enzyme poisoning. Thus, the activity of covalent topoisomerase II poisons appears to be less sensitive to stereochemical changes than interfacial poisons. PMID:23514406

  8. Biomimetic Modeling of Copper Complexes: A Study of Enantioselective Catalytic Oxidation on D-(+-Catechin and L-(−-Epicatechin with Copper Complexes

    Directory of Open Access Journals (Sweden)

    Francesco G. Mutti

    2008-01-01

    Full Text Available The biomimetic catalytic oxidations of the dinuclear and trinuclear copper(II complexes versus two catechols, namely, D-(+-catechin and L-(−-epicatechin to give the corresponding quinones are reported. The unstable quinones were trapped by the nucleophilic reagent, 3-methyl-2-benzothiazolinone hydrazone (MBTH, and have been calculated the molar absorptivities of the different quinones. The catalytic efficiency is moderate, as inferred by kinetic constants, but the complexes exhibit significant enantio-differentiating ability towards the catechols, albeit for the dinuclear complexes, this enantio-differentiating ability is lower. In all cases, the preferred enantiomeric substrate is D-(+-catechin to respect the other catechol, because of the spatial disposition of this substrate.

  9. Mechanical, physico-chemical, and antimicrobial properties of gelatin-based film incorporated with catechin-lysozyme

    Directory of Open Access Journals (Sweden)

    Rawdkuen Saroat

    2012-11-01

    Full Text Available Abstract Background Microbial activity is a primary cause of deterioration in many foods and is often responsible for reduced quality and safety. Food-borne illnesses associated with E. coli O157:H7, S. aureus, S. enteritidis and L. monocytogenes are a major public health concern throughout the world. A number of methods have been employed to control or prevent the growth of these microorganisms in food. Antimicrobial packaging is one of the most promising active packaging systems for effectively retarding the growth of food spoilage and pathogenic microorganisms. The aim of this study was to determine the mechanical, physico-chemical properties and inhibitory effects of the fish gelatin films against selected food spoilage microorganisms when incorporated with catechin-lysozyme. Results The effect of the catechin-lysozyme combination addition (CLC: 0, 0.125, 0.25, and 0.5%, w/v on fish gelatin film properties was monitored. At the level of 0.5% addition, the CLC showed the greatest elongation at break (EAB at 143.17% with 0.039 mm thickness, and the lowest water vapor permeability (WVP at 6.5 x 10−8 g·mm·h-1·cm-2·Pa-1, whereas the control showed high tensile strength (TS and the highest WVP. Regarding color attributes, the gelatin film without CLC addition gave the highest lightness (L* 91.95 but lowest in redness (a*-1.29 and yellowness (b* 2.25 values. The light transmission of the film did not significantly decrease and nor did film transparency (p>0.05 with increased CLC. Incorporating CLC could not affect the film microstructure. The solubility of the gelatin based film incorporated with CLC was not affected, especially at a high level of addition (p>0.05. Inhibitory activity of the fish gelatin film against E.coli, S.aureus, L. innocua and S. cerevisiae was concentration dependent. Conclusions These findings suggested that CLC incorporation can improve mechanical, physico-chemical, and antimicrobial properties of the resulting films

  10. Strong Inhibition of Secretory Sphingomyelinase by Catechins, Particularly by (-)-Epicatechin 3-O-Gallate and (-)-3'-O-Methylepigallocatechin 3-O-Gallate.

    Science.gov (United States)

    Kobayashi, Keiko; Ishizaki, Yuki; Kojo, Shosuke; Kikuzaki, Hiroe

    2016-01-01

    Sphingomyelinases (SMases) are key enzymes involved in many diseases which are caused by oxidative stress, such as atherosclerosis, diabetes mellitus, nonalcoholic fatty liver disease, and Alzheimer's disease. SMases hydrolyze sphingomyelin to generate ceramide, a well-known pro-apoptotic lipid. SMases are classified into five types based on pH optimum, subcellular localization, and cation dependence. Previously, we demonstrated that elevation of secretory sphingomyelinase (sSMase) activity increased the plasma ceramide concentration under oxidative stress induced by diabetes and atherosclerosis in murine models. These results suggest that sSMase inhibitors can prevent the progress of these diseases. The present study demonstrated that sSMase activity was activated by oxidation and inhibited by reduction. Furthermore, we examined whether catechins inhibited the sSMase activity in a physiological plasma concentration. Among catechins, (-)-epicatechin 3-O-gallate (ECg) exhibited strong inhibitory effect on sSMase (IC50=25.7 μM). This effect was attenuated by methylation at the 3″- or 4″-position. On the other hand, (-)-epigallocatechin 3-O-gallate (EGCg) and (-)-catechin 3-O-gallate (Cg) exhibited weaker inhibitory activity than ECg, and (-)-epicatechin and (-)-epigallocatechin did not affect sSMase activity. Additionally, one synthetic catechin, (-)-3'-O-methylepigallocatechin 3-O-gallate (EGCg-3'-O-Me), showed the strongest inhibitory effect (IC50=1.7 μM) on sSMase. This phenomenon was not observed for (-)-4'-O-methylepigallocatechin 3-O-gallate. These results suggest that the reduction potential, the presence of the galloyl residue at the C-3 position, and the steric requirement to interact with sSMase protein are important for effective inhibition of sSMase. PMID:27264097

  11. Določitev galne kisline, pirokatehola, floroglucinola, resorcinola in katehina s tankoplastno kromatografijo: Thin-layer chromatography of gallic acid, pyrocatehol, phloroglucinol, resorcinol and catechin:

    OpenAIRE

    OVEN, PRIMOŽ; Poljanšek, Ida; Vek, Viljem

    2011-01-01

    The suitability of six solvent systems for the thin-layer chromatographic separation of simple phenolic compounds such as gallic acid, pyrocatechol phloroglucinol, resorcinol and related compound catechin were investigated. The most appropriate developing solvent systems for the separation of these organic compounds were chloroform - ethyl acetate - acetic acid (50 : 50 : 1) and toluene -acetonitrile - formic acid (70 : 30 : 1). The best separation of the five organic compounds was achieved u...

  12. Potential in vitro Protective Effect of Quercetin, Catechin, Caffeic Acid and Phytic Acid against Ethanol-Induced Oxidative Stress in SK-Hep-1 Cells

    OpenAIRE

    Lee, Ki-Mo; Kang, Hyung-Sik; Yun, Chul-Ho; Kwak, Hahn-Shik

    2012-01-01

    Phytochemicals have been known to exhibit potent antioxidant activity. This study examined cytoprotective effects of phytochemicals including quercetin, catechin, caffeic acid, and phytic acid against oxidative damage in SK-Hep-1 cells induced by the oxidative and non-oxidative metabolism of ethanol. Exposure of the cells to excess ethanol resulted in a significant increase in cytotoxicity, reactive oxygen species (ROS) production, lipid hydroperoxide (LPO), and antioxidant enzyme activity. E...

  13. The Powdering Process with a Set of Ceramic Mills for Green Tea Promoted Catechin Extraction and the ROS Inhibition Effect

    Directory of Open Access Journals (Sweden)

    Kouki Fujioka

    2016-04-01

    Full Text Available For serving green tea, there are two prominent methods: steeping the leaf or the powdered leaf (matcha style in hot water. The purpose of the present study was to reveal chemical and functional differences before and after the powdering process of green tea leaf, since powdered green tea may contribute to expanding the functionality because of the different ingesting style. In this study, we revealed that the powdering process with a ceramic mill and stirring in hot water increased the average extracted concentration of epigallocatechin gallate (EGCG by more than three times compared with that in leaf tea using high-performance liquid chromatography (HPLC and liquid chromatography–tandem mass Spectrometry (LC-MS/MS analyses. Moreover, powdered green tea has a higher inhibition effect of reactive oxygen species (ROS production in vitro compared with the same amount of leaf tea. Our data suggest that powdered green tea might have a different function from leaf tea due to the higher catechin contents and particles.

  14. The Powdering Process with a Set of Ceramic Mills for Green Tea Promoted Catechin Extraction and the ROS Inhibition Effect.

    Science.gov (United States)

    Fujioka, Kouki; Iwamoto, Takeo; Shima, Hidekazu; Tomaru, Keiko; Saito, Hideki; Ohtsuka, Masaki; Yoshidome, Akihiro; Kawamura, Yuri; Manome, Yoshinobu

    2016-01-01

    For serving green tea, there are two prominent methods: steeping the leaf or the powdered leaf (matcha style) in hot water. The purpose of the present study was to reveal chemical and functional differences before and after the powdering process of green tea leaf, since powdered green tea may contribute to expanding the functionality because of the different ingesting style. In this study, we revealed that the powdering process with a ceramic mill and stirring in hot water increased the average extracted concentration of epigallocatechin gallate (EGCG) by more than three times compared with that in leaf tea using high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass Spectrometry (LC-MS/MS) analyses. Moreover, powdered green tea has a higher inhibition effect of reactive oxygen species (ROS) production in vitro compared with the same amount of leaf tea. Our data suggest that powdered green tea might have a different function from leaf tea due to the higher catechin contents and particles. PMID:27077834

  15. Combinational enhancing effects of formulation and encapsulation on digestive stability and intestinal transport of green tea catechins.

    Science.gov (United States)

    Son, Yu-Ra; Chung, Jae-Hwan; Ko, Sanghoon; Shim, Soon-Mi

    2016-01-01

    The hypothesis was that green tea catechins (GTCs) formulated with vitamin C and xylitol followed by enteric coating with hydroxypropyl methyl cellulose phthalate (HPMCP) or encapsulated into γ-cyclodextrin (γ-CD) could enhance intestinal absorption of GTCs. Surface morphology and size obtained by SEM were different. Digestive stability of GTCs encapsulated into γ-CD or coated with HPMCP was enhanced up to 65.56% or 57.63%, respectively. When GTCs were formulated, the digestive stability was greater than the one not formulated. Formulated GTCs followed by encapsulation into γ-CD significantly increased intestinal transport. Absorption of GTCs was 2.8%, 9.64%, 11.97%, 8.41% and 14.36% for only GTCs, GTCs encapsulated into γ-CD, formulated GTCs encapsulated into γ-CD, GTCs coated with HPMCP and formulated GTCs coated with HPMCP, respectively. This study suggests that GTCs, formulated with vitamin C and xylitol followed by γ-CD encapsulation or HPMCP enteric coating, provide combinational effect to increase bioavailability of GTCs. PMID:26878684

  16. Profiling a gut microbiota-generated catechin metabolite's fate in human blood cells using a metabolomic approach.

    Science.gov (United States)

    Mülek, Melanie; Fekete, Agnes; Wiest, Johannes; Holzgrabe, Ulrike; Mueller, Martin J; Högger, Petra

    2015-10-10

    The microbial catechin metabolite δ-(3,4-dihydroxy-phenyl)-γ-valerolactone (M1) has been found in human plasma samples after intake of maritime pine bark extract (Pycnogenol). M1 has been previously shown to accumulate in endothelial and blood cells in vitro after facilitated uptake and to exhibit anti-inflammatory activity. The purpose of the present research approach was to systematically and comprehensively analyze the metabolism of M1 in human blood cells in vitro and in vivo. A metabolomic approach that had been successfully applied for drug metabolite profiling was chosen to detect 19 metabolite peaks of M1 which were subsequently further analyzed and validated. The metabolites were categorized into three levels of identification according to the Metabolomics Standards Initiative with six compounds each confirmed at levels 1 and 2 and seven putative metabolites at level 3. The predominant metabolites were glutathione conjugates which were rapidly formed and revealed prolonged presence within the cells. Although a formation of an intracellular conjugate of M1 and glutathione (M1-GSH) was already known two GSH conjugate isomers, M1-S-GSH and M1-N-GSH were observed in the current study. Additionally detected organosulfur metabolites were conjugates with oxidized glutathione and cysteine. Other biotransformation products constituted the open-chained ester form of M1 and a methylated M1. Six of the metabolites determined in in vitro assays were also detected in blood cells in vivo after ingestion of the pine bark extract by two volunteers. The present study provides the first evidence that multiple and structurally heterogeneous polyphenol metabolites can be generated in human blood cells. The bioactivity of the M1 metabolites and their contribution to the previously determined anti-inflammatory effects of M1 now need to be elucidated. PMID:26025814

  17. Green tea catechins decrease total and low-density lipoprotein cholesterol: a systematic review and meta-analysis.

    Science.gov (United States)

    Kim, Amie; Chiu, Andrew; Barone, Meredith K; Avino, Diane; Wang, Fei; Coleman, Craig I; Phung, Olivia J

    2011-11-01

    Green tea catechins (GTCs) have been studied in randomized control trials for their lipid-lowering effects. Studies, however, have been small and demonstrated conflicting results. The objective of this study was to perform a systematic review and meta-analysis of randomized controlled trials evaluating the relationship between GTCs and serum lipid levels, including total, low-density lipoprotein (LDL), high-density lipoprotein (HDL) cholesterol, and triglycerides. A systematic literature search of MEDLINE, EMBASE, Cochrane CENTRAL, and the Natural Medicines Comprehensive Database was conducted through March 2010. Randomized controlled trials evaluating GTCs vs control in human beings and reporting efficacy data on at least one of the aforementioned serum lipid endpoints were included. Weighted mean differences for changes from baseline (with 95% confidence intervals [CIs]) for lipid endpoints were calculated using random-effects models. Twenty trials (N=1,415) met all inclusion criteria. Upon meta-analysis, GTCs at doses ranging from 145 to 3,000 mg/day taken for 3 to 24 weeks reduced total (-5.46 mg/dL [-0.14 mmol/L]; 95% CI -9.59 to -1.32) and LDL cholesterol (-5.30 mg/dL [-0.14 mmol/L]; 95% CI -9.99 to -0.62) compared to control. GTCs did not significantly alter HDL cholesterol (-0.27 mg/dL [-0.007 mmol/L]; 95% CI -1.62 to 1.09) or triglyceride (3.00 mg/dL [-0.034 mmol/L]; 95% CI -2.73 to 8.73) levels. The consumption of GTCs is associated with a statistically significant reduction in total and LDL cholesterol levels; however, there was no significant effect on HDL cholesterol or triglyceride levels. PMID:22027055

  18. Determination of some hydroxybenzoic acids and catechins in white wine samples by liquid chromatography with luminescence detection.

    Science.gov (United States)

    Rodríguez-Díaz, Rafael Carlos; Paz Aguilar-Caballos, María; Gómez-Hens, Agustina

    2006-12-01

    A liquid chromatographic method with luminescence detection for the determination of eight phenolic compounds is reported. The method involves postcolumn derivatization with terbium(III). This derivatization is based on the reaction between phenolics and terbium(III) to form luminescent chelates, which were determined at lamda ex 295 and lamda em 545 nm using the fluorescence mode. The long wavelength emission of lanthanide chelates can minimize interferences from background sample matrix, which usually emit at shorter wavelengths. Also, the chromatographic separation allows the individual determination of phenolics, which cannot be done using the direct measurement of the fluorescence of their corresponding terbium chelates. Dynamic ranges of the calibration graphs and detection limits, obtained with standard solutions of analytes were (microg/mL): gallic acid (0.9-40, 0.3), protocatechuic acid (0.05-7, 0.016), catechin (0.2-40, 0.07), vanillic acid (0.25-40, 0.08), p-hydroxybenzoic acid (0.8-40, 0.25), syringic acid (0.17-40, 0.05), epicatechin (0.3-40, 0.09) and salicylic acid (0.07-12, 0.02). The precision was established at two concentration levels of each analyte and expressed as the percentage of RSD with values ranging between 1.0 and 6.5%. The practical usefulness of the method was demonstrated by the analysis of white wine samples, which were diluted two-fold and directly injected into the chromatographic system. The recovery values obtained ranged between 93.3 and 108.0%. PMID:17305238

  19. Contents of Caffeine and Catechin in Guizhou Green Tea%贵州绿茶中咖啡碱和儿茶素含量分析

    Institute of Scientific and Technical Information of China (English)

    李俊; 郭晓关; 庞宏宇; 朱福建; 王震; 赖飞

    2012-01-01

    Contents of caffeine and catechin of 243 green tea samples from Guizhou province are detected, using high performance liquid chromatographic (HPLC). The results show that, the catechin contents range 9.14%~27.28% in green tea of Guizhou province, the average content is 15.71%. The caffeine contents range 1.08%~3.33%, the average content is 2.24%. The catechin quality indexes of samples from 9 regions mainly are 1 000-2 000, and the highest one (the sample is from Qiannan) is 1 975.51. The catechin bitter taste index of samples from 9 regions mainly are 8.00-17.04. According to the results, there is high value for making use of effective components of Guizhou green tea, and developing high quality spring tea is strongly recommended, and relatively the autumn tea is suitable for deep processing or extracting active principles.%对贵州省243份绿茶样品中咖啡碱和儿茶素类物质采用高效液相色谱方法进行检测.结果表明:贵州省绿茶中儿茶素含量范围为9.14%~27.28%,平均含量15.71%;咖啡碱含量为1.08%~3.33%,平均含量2.24%.各地区茶叶儿茶素品质指数多数为1000~2000,其中黔南地区的最高为1975.51;各地区的儿茶素苦涩味指数主要在8.00~17.04之间,黔西南地区的苦涩味指数最低为8.00.据此分析可得,贵州绿茶具有很高的利用价值,春茶适合开发高品质的名优茶,秋茶适合用于茶叶深加工或有效成分的提取.

  20. Addition of tea catechins and vitamin C on sensory evaluation, colour and lipid stability during chilled storage in cooked or raw beef and chicken patties.

    Science.gov (United States)

    Mitsumoto, Mitsuru; O'Grady, Michael N; Kerry, Joe P; Joe Buckley, D

    2005-04-01

    The effects of addition of tea catechins (TC) and vitamin C (VC) on sensory evaluation, colour and lipid stability in cooked or raw beef and chicken meat patties during refrigerated storage were studied. Fresh beef striploin and chicken breast muscles were minced, following removal of external fat and connective tissue. Following mincing, beef and chicken were assigned to one of the following five treatments: control (meat treated with no antioxidant); TC200, meat plus 200 mg TC/kg muscle; TC400, meat plus 400 mg TC/kg muscle; VC200, meat plus 200 mg VC/kg muscle, VC400, meat plus 400 mg VC/kg muscle. Sodium chloride (1%) was added to all samples. Patties (125 g portions), formed from the above-treated minced meat, were oven cooked, cooled, and packaged in 30% CO(2):70% N(2). Fresh raw beef and chicken patties were packaged in 80% O(2):20% CO(2). All samples were stored for up to 7 days under fluorescent lighting at 4 °C. Sensory parameters (colour, flavour, taste, tenderness and overall acceptability) were evaluated on cooked beef and chicken patties after 1, 3 and 6 days of storage. Surface colour (Hunter L, a and b values), and lipid oxidation (2-thiobarbituric acid reactive substances) were measured on days 1, 3 and 6 of storage for cooked meats and on days 2 and 7 for raw beef and chicken. Tea catechins addition (200 or 400 mg/kg) to minced meat caused (P<0.05) discolouration in cooked beef and chicken meat patties and significantly reduced (P<0.001) lipid oxidation in cooked or raw beef patties compared to the control. Beef, either raw or cooked, was more susceptible (P<0.01) to oxidation compared to chicken. Raw meat stored in high oxygen conditions was more susceptible to lipid oxidation than cooked meat stored in anaerobic conditions. Tea catechins treatments (TC200 and TC400) inhibited (P<0.05) lipid oxidation in raw beef to a greater extent than vitamin C treatments (VC200 and VC400). These results indicate that tea catechins are potent natural

  1. Thermodynamic and kinetic properties of a red wine pigment: catechin-(4,8)-malvidin-3-O-glucoside.

    Science.gov (United States)

    Nave, Frederico; Petrov, Vesselin; Pina, Fernando; Teixeira, Natércia; Mateus, Nuno; de Freitas, Victor

    2010-10-28

    Catechin-(4,8)-malvidin-3-glucoside, a red pigment adduct (at acid pH) found in red wine and resulting from the reaction between malvidin-3-glucoside and flavan-3-ols during wine aging, was synthesized. The thermodynamic and kinetic constants of the network of chemical reactions were fully determined by stopped flow: (i) Direct pH jumps, from thermal equilibrated solutions at pH = 1.0 (flavylium cation, AH(+)), show three kinetic processes. The first one occurs within the mixing time of the stopped flow and leads to the formation of quinoidal bases A and/or A(-) depending on the final pH; the second one takes place with a rate constant equal to 0.075 + 33[H(+)] and was attributed to the hydration reaction that forms the pseudobases (hemiketals), B/B(-). The third process is much slower, 2 × 10(-4) s(-1), and is due to the cis-trans isomerization giving rise to a small fraction of trans-chalcones, Ct/Ct(-). (ii) Reverse pH jumps from the thermally equilibrated solution at moderate to neutral pH values back to a sufficiently acidic medium clearly distinguish three kinetic processes: the first one takes place within the dead time and is due to the protonation of the bases; the second process occurs with the same rate constant of the hydration reaction monitored by direct pH jumps and is attributed to the formation of flavylium cation from the B; the last process occurs with a rate constant of 1.8 s(-1), and results from the formation of AH(+) from Ct through B, reflecting the rate of the ring closure (tautomerization). The separation of the hydration from the tautomerization upon a reverse pH jump is only possible because at pH < 1 the former reaction is faster than the last. An identical situation was observed for malvidin-3-glucoside (oenin) for pH < 2. PMID:20925351

  2. Elucidation of the Corrosion Inhibition of Mild Steel in 1.0 M HCl by Catechin Monomers from Commercial Green Tea Extracts

    Science.gov (United States)

    Nofrizal, S.; Rahim, Afidah A.; Saad, Bahruddin; Bothi Raja, P.; Shah, Affaizza M.; Yahya, S.

    2012-04-01

    The inhibitive action of commercial green tea extracts on mild steel (MS) in a 1.0 M hydrochloric acid solution was investigated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). A high-performance liquid chromatographic (HPLC) analysis showed conclusively that of the eight catechin monomers and caffeine found in the original extracts, only four components were responsible for the inhibition of MS. The decreasing adsorption capacity of monomers on MS is related to the stereochemistry of molecules and the number of phenolic groups, and it is as follows: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin. Adsorption of green tea extract constituent was found to follow Langmuir adsorption isotherm and the calculated Gibb's free energy values indicated the physisorption of inhibitor over MS surface. Physisorption was supported well by the potential zero charge (PZC) and molecular surface energy-level calculations.

  3. A Significant Inhibitory Effect on Advanced Glycation End Product Formation by Catechin as the Major Metabolite of Lotus Seedpod Oligomeric Procyanidins

    Directory of Open Access Journals (Sweden)

    Qian Wu

    2014-08-01

    Full Text Available Several lines of evidence suggested that B-type procyanidin oligomers from lotus seedpod (LSOPC may effectively modulate the formation of advanced glycation end products (AGEs. In vivo, LSOPC is metabolized by intestinal flora to become various kinds of phenolic compounds that possess potent antioxidant activities. However, few reports of the absorption and metabolism of LSOPC have been revealed. In the present study, rats were orally administered with LSOPC at a dose of 300 mg/kg body weight. The metabolites of LSOPC in urine were elucidated by HPLC-MS/MS analysis 24 h post-administration. Eight major metabolites were significantly increased by the administration of 300 mg/kg of LSOPC (p < 0.01. The anti-glycative activity of LSOPC and its metabolites were investigated. The results showed that LSOPC and catechin had greater anti-glycative activities than other metabolites, which were positively correlated to their carbonyl scavenging activities and antioxidant capacities.

  4. 中低压柱层析分离儿茶素的研究%STUDY ON PURIFICATION OF CATECHINS BY COLUMN CHROMATOGRAPHY

    Institute of Scientific and Technical Information of China (English)

    赖榕辉; 黄亚辉

    2012-01-01

    采用全自动中低压柱层析制备色谱分离儿茶素,原料为含量高于85%的茶多酚,分别以硅胶、C18(十八烷基键合相硅胶)作为吸附剂,应用HPLC对分离产物进行鉴定.结果表明,以硅胶作为吸附剂时,甲醇和氯仿溶液梯度洗脱,得到纯度为96.3%的EGCG,得率32%;以C18作为吸附剂时,甲醇和水溶液梯度洗脱,得到90%以上纯度的EGCG、EC、ECG、CG 4种儿茶素,得率分别为28.8%、7.7%、17.0%、1.8%.%A Flash Chromatography System, EZ Purifier IE, was used to purification catechins. The raw material was tea polyphenols of 85% pure, and the filling material were silica gel and C18 (octadecyl silane) respectively. Components of catechins were tested by HPLC. Results showed that using silica gel as filling material, methanol-chloroform as eluting solvent, 96.3% purity of EGCG monomer had been achieved with 32% yield. When using C18 as filling material, methanol-water as eluting solvent, more then 90% purity of EGCG, EC, ECG and CG monomers had been achieved with 28.8%, 7.7%, 17.0%, 1.8% yield, respectively.

  5. Effects of Caffeine and Catechins Combination on Live Lipids Metabolism Relative Enzymes in Mice%咖啡碱与茶多酚组合对小鼠肝脏脂肪代谢酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    杨丽聪; 郑国栋; 蒋艳; 尹忠平; 徐明生

    2011-01-01

    Objective: To investigate the effects of caffeine and catechins combination on mechanism of lipids metabolism in mice.Method: Fifty female kunming mice were randomly divided into 5 groups: control, 0.03% caffeine +0.3% catechins, 0.03% caffeine + 0.6% catechins, 0.06% caffeine + 0.3% catechins and 0.06% caffeine + 0.6% catechins for 12 weeks.Live and intraperitioneal adipose tissues (IPAT) were weighted at the end of this period.Carnitine acyltransferase (CAT), acyl-CoA oxidase (ACO) and fatty acid synthase (FAS) activity in the liver were measured.Results: The body weight and body weight gain was significantly reduced by the diets containing 0.06% caffeine + 0.6%catechins.The conbinations of green tea components significantly reduced the IPAT coefficient, increased the activity of CAT with compared to the control, and 0.06% caffeine + 0.6% catechins can significantly increase the ACO activity, the FAS activity were significantly reduced by 0.03% caffeine + 0.6% catechins and 0.06% caffeine + 0.6% catechins.Conclusion: These results showed that the green tea components may reduce the activity of FAS, increase activities of CAT and ACO, it causes the suppressive effect on fat accumulation and body weight gain.%目的:研究绿茶功能性成分--咖啡碱与茶多酚组合用于减肥的代谢机制.方法:将50只雌性昆明小鼠随机分成5组,即:对照组、0.03%咖啡碱+0.3%茶多酚、0.03%咖啡碱+0.6%茶多酚、0.06%咖啡碱+0.3%茶多酚及0.06%咖啡碱+0.6%茶多酚.投喂12周后解剖,摘取小鼠的肝及腹腔脂肪(IPAT)并称重.测定小鼠肝脏肉毒碱脂酰转移酶(CAT)、酰基辅酶A氧化酶(ACO)及脂肪酸合成酶(FAS)活性.结果:0.06%咖啡碱+0.6%茶多酚组小鼠的体重及体重增加与对照组相比显著降低.绿茶成分组合的腹腔脂肪系数明显低于对照组,CAT活性与对照组相比均显著提高.0.03%咖啡碱+0.6%茶多酚及0.06%咖啡碱+0.6%

  6. EGCG, a major green tea catechin suppresses breast tumor angiogenesis and growth via inhibiting the activation of HIF-1α and NFκB, and VEGF expression.

    Science.gov (United States)

    Gu, Jian-Wei; Makey, Kristina L; Tucker, Kevan B; Chinchar, Edmund; Mao, Xiaowen; Pei, Ivy; Thomas, Emily Y; Miele, Lucio

    2013-01-01

    The role of EGCG, a major green tea catechin in breast cancer therapy is poorly understood. The present study tests the hypothesis that EGCG can inhibit the activation of HIF-1α and NFκB, and VEGF expression, thereby suppressing tumor angiogenesis and breast cancer progression. Sixteen eight-wk-old female mice (C57BL/6 J) were inoculated with 10^6 E0771 (mouse breast cancer) cells in the left fourth mammary gland fat pad. Eight mice received EGCG at 50-100 mg/kg/d in drinking water for 4 weeks. 8 control mice received drinking water only. Tumor size was monitored using dial calipers. At the end of the experiment, blood samples, tumors, heart and limb muscles were collected for measuring VEGF expression using ELISA and capillary density (CD) using CD31 immunohistochemistry. EGCG treatment significantly reduced tumor weight over the control (0.37 ± 0.15 vs. 1.16 ± 0.30 g; P < 0.01), tumor CD (109 ± 20 vs. 156 ± 12 capillary #/mm^2; P < 0.01), tumor VEGF expression (45.72 ± 1.4 vs. 59.03 ± 3.8 pg/mg; P < 0.01), respectively. But, it has no effects on the body weight, heart weight, angiogenesis and VEGF expression in the heart and skeletal muscle of mice. EGCG at 50 μg/ml significantly inhibited the activation of HIF-1α and NFκB as well as VEGF expression in cultured E0771 cells, compared to the control, respectively. These findings support the hypothesis that EGCG, a major green tea catechin, directly targets both tumor cells and tumor vasculature, thereby inhibiting tumor growth, proliferation, migration, and angiogenesis of breast cancer, which is mediated by the inhibition of HIF-1α and NFκB activation as well as VEGF expression. PMID:23638734

  7. Development of a UFLC-MS/MS method for the simultaneous determination of seven tea catechins in rat plasma and its application to a pharmacokinetic study after administration of green tea extract.

    Science.gov (United States)

    Huo, Yanshuang; Zhang, Qian; Li, Qing; Geng, Bingjie; Bi, Kaishun

    2016-06-01

    A rapid, sensitive and selective ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method was developed and validated for simultaneous determination of seven green tea catechins including catechin (C), (-)-epicatechin (EC), gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG), gallocatechin-3-gallate (GCG) and (-)-epigallocatechin-3-gallate (EGCG) in rat plasma. The plasma samples were firstly hydrolysed with the mixture of β-glucuronidase and sulfatase, which were then extracted by liquid-liquid extraction with ethyl acetate-isopropanol (1:1, v/v). The analytes were separated on a Venusil MP C18 column (Venusil, China) with a gradient elution at a flow rate of 0.4mL/min. The detection was performed in negative ionization and multiple reaction monitoring (MRM) mode. All the calibration curves exhibited good linearity (r>0.9943) with intra- and inter-day precisions of less than 14.3% and the accuracy deviations ranging from -8.8% to 7.5%. The extraction recoveries of the analytes and ethyl gallate (internal standard) were all more than 72%. The validated method was successfully applied to a pharmacokinetic study of seven catechins in rat plasma after oral administration of the green tea extract at different doses of 0.4, 1.2 and 2.0g/kg. PMID:27037979

  8. The Combination of Catechin and Epicatechin Gallate from Fructus Crataegi Potentiates β-Lactam Antibiotics Against Methicillin-Resistant Staphylococcus aureus (MRSA in Vitro and in Vivo

    Directory of Open Access Journals (Sweden)

    Jiang Zheng

    2013-01-01

    Full Text Available Fructus crataegi (hawthorn is the common name of all plant species in the genus Crataegus of the Rosaceae family. In the present study, three monomers of (+-catechin (C, (−-epicatechin gallate (ECg and (−-epigallocatechin (EGC were isolated from the hawthorn under the guide of antibacterial sensitization activity. The bioactivity of the composite fraction in enhancing the antibacterial effect of oxacillin against methicillin-resistant Staphylococcus aureus (MRSA was greater than that of the individual monomer of the hawthorn extract in vitro. Two-fold dilution and checkerboard methods were used to analyze antibacterial activity and screen for the combination and proportion of monomers with the best bioactivity. The result showed that C (128 mg/L combined with ECg (16 mg/L had the greatest effect and the combination also reduced the bacterial load in blood of septic mice challenged with a sublethal dose of MRSA, increased daunomycin accumulation within MRSA and down-regulated the mRNA expression of norA, norC and abcA, three important efflux pumps of MRSA. In summary, C and ECg enhanced the antibacterial effect of β-lactam antibiotics against MRSA in vitro and in vivo, which might be related to the increased accumulation of antibiotics within MRSA via suppression of important efflux pumps’ gene expression.

  9. Tea Catechins Protect Goat Skeletal Muscle against H₂O₂-Induced Oxidative Stress by Modulating Expression of Phase 2 Antioxidant Enzymes.

    Science.gov (United States)

    Zhong, Rong-Zhen; Fang, Yi; Qin, Gui-Xin; Li, Hao-Yang; Zhou, Dao-Wei

    2015-09-16

    To study the mechanisms of tea catechins (TCs) in goat muscles against oxidative stress, skeletal muscle cells (SMCs) induced by H2O2 or not were incubated with TCs or 3H-1,2-dithiole-3-thione (D3T) and were defined as H2O2, H2O2D3T, H2O2TC, D3T, and TC treatments, respectively. Results showed that, similar to effects of D3T, TCs regulated mRNA and protein expression of antioxidant enzymes by suppressing Keap1 protein expression in SMCs from 1.58 ± 0.12 to 0.71 ± 0.21 and 1.03 ± 0.11 in H2O2TC and TC groups, respectively; however, effects differed in oxidative condition of cells and among enzymes. In stressed cells, TCs increased catalase and glutathione S-transferases (GST) activities (P goats fed grain supplemented with TCs or D3T following infusion with H2O2 was conducted to further verify mechanisms of TC action. As seen in vitro, TCs reduced Keap1 protein expression (P goats under both conditions increased meat color and tenderness (P ≤ 0.001). In conclusion, TCs protected goat muscles against oxidative stress and subsequently improved meat quality by modulating phase 2 antioxidant enzymes and Keap1 expression. PMID:26118494

  10. The Effect of Dietary Supplementation of Green Tea Catechins on Cardiovascular Disease Risk Markers in Humans: A Systematic Review of Clinical Trials

    Directory of Open Access Journals (Sweden)

    Sarah O. Lau

    2016-06-01

    Full Text Available Green tea catechins (GTCs are secondary plant metabolites that have been associated with health benefits in human trials. As such, they have the potential to reduce cardiovascular disease (CVD risk; however, results are not consistent. This systematic review of the published data assessed the putative effect of GTCs supplementation on anthropometric, blood pressure, and biochemical measures associated with CVD risk. It was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA guidelines exploring four major electronic databases (MEDLINE, Cochrane Library, Web of Science, and Scopus. Studies were included if they were published in peer-reviewed journals in English from 1990 until October 2015, and were human double-blind randomized and placebo-controlled trials (RCTs. From 122,428 articles initially identified, after two levels of screening, seven studies met the inclusion criteria. The review revealed consistent and significant (p ≤ 0.05 reductions in body mass index (BMI, blood pressure and plasma lipids; however, this effect would have been less if between-group effects had been considered. The current evidence base also has considerable methodological limitations due to suboptimal statistical methods used in data analyses. Future research efforts must aim to rectify this paucity of evidence with well-designed and well-reported prospective studies.

  11. Green tea compound epigallo-catechin-3-gallate (EGCG) increases neuronal survival in adult hippocampal neurogenesis in vivo and in vitro.

    Science.gov (United States)

    Ortiz-López, L; Márquez-Valadez, B; Gómez-Sánchez, A; Silva-Lucero, M D C; Torres-Pérez, M; Téllez-Ballesteros, R I; Ichwan, M; Meraz-Ríos, M A; Kempermann, G; Ramírez-Rodríguez, G B

    2016-05-13

    Epigallo-catechin-3-gallate (EGCG), found in the leaves of Camellia sinensis (green tea), has antioxidant- and scavenger-functions and acts neuroprotectively. It has been publicized as anti-aging remedy but data on potential cellular mechanisms are scarce. Recent studies claimed that EGCG specifically promotes neural precursor cell proliferation in the dentate gyrus of C57Bl/6 mice, without changes at the level of immature and mature new neurons. We here analyzed the effects of EGCG on adult hippocampal neurogenesis in male Balb/C mice and saw a different pattern. Two weeks of treatment with EGCG (0, 0.625, 1.25, 2.5, 5 and 10mg/kg) showed a dose-response curve that peaked at 2.5mg/kg of EGCG with significantly increased cell survival without affecting cell proliferation but decreasing apoptotic cells. Also, EGCG increased the population of doublecortin-(DCX)-expressing cells that comprises the late intermediate progenitor cells (type-2b and -3) as well as immature neurons. After EGCG treatment, the young DCX-positive neurons showed more elaborated dendritic trees. EGCG also significantly increased net neurogenesis in the adult hippocampus and increased the hippocampal levels of phospho-Akt. Ex vivo, EGCG exerted a direct effect on survival and neuronal differentiation of adult hippocampal precursor cells, which was absent, when PI3K, a protein upstream of Akt, was blocked. Our results thus support a pro-survival and a pro-neurogenic role of EGCG. In the context of the conflicting published results, however, potential genetic modifiers must be assumed. These might help to explain the overall variability of study results with EGCG. Our data do indicate, however, that natural compounds such as EGCG can in principle modulate brain plasticity. PMID:26917271

  12. Vitamin A or E and a catechin synergize as vaccine adjuvant to enhance immune responses in mice by induction of early interleukin-15 but not interleukin-1β responses.

    Science.gov (United States)

    Patel, Sapna; Akalkotkar, Archana; Bivona, Joseph J; Lee, Ji-Young; Park, Young-Ki; Yu, Mingke; Colpitts, Sara L; Vajdy, Michael

    2016-08-01

    Vitamins A and E and select flavonoids in the family of catechins are well-defined small molecules that, if proven to possess immunomodulatory properties, hold promise as vaccine adjuvants and various therapies. In an effort to determine the in vivo immunomodulatory properties of these molecules, we found that although mucosal and systemic vaccinations with a recombinant HIV-1BaL gp120 with either a catechin, epigallo catechin gallate (EGCG) or pro-vitamin A (retinyl palmitate) alone in a vegetable-oil-in-water emulsion (OWE) suppressed antigen-specific responses, the combination of EGCG and vitamin A or E in OWE (Nutritive Immune-enhancing Delivery System, NIDS) synergistically enhanced adaptive B-cell, and CD4(+) and CD8(+) T-cell responses, following induction of relatively low local and systemic innate tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-17, but relatively high levels of early systemic IL-15 responses. For induction of adaptive interferon-γ and TNF-α responses by CD4(+) and CD8(+) T cells, the adjuvant effect of NIDS was dependent on both IL-15 and its receptor. In addition, the anti-oxidant activity of NIDS correlated positively with higher expression of the superoxide dismutase 1, an enzyme involved in reactive oxygen species elimination but negatively with secretion of IL-1β. This suggests that the mechanism of action of NIDS is dependent on anti-oxidant activity and IL-15, but independent of IL-1β and inflammasome formation. These data show that this approach in nutritive vaccine adjuvant design holds promise for the development of potentially safer effective vaccines. PMID:27135790

  13. Simultaneous quantification of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid in rat plasma by HPLC-MS/MS: application to a pharmacokinetic study of Longhu Rendan pills.

    Science.gov (United States)

    Wang, Tianming; Ding, Liqing; Jin, Huajia; Shi, Rong; Li, Yuanyuan; Wu, Jiasheng; Li, Yifei; Zhu, Li; Ma, Yueming

    2016-08-01

    A sensitive, specific, accurate HPLC-MS/MS method was developed and validated for the simultaneous quantification of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid from Longhu Rendan pills in rat plasma. Chromatographic separation was performed with a Hypersil Gold C18 column using a gradient of methanol and 0.01% acetic acid containing 0.2 mm ammonium acetate as mobile phase. The analytes were quantified on a triple quadrupole mass spectrometer, operating in selected reaction monitoring mode and switching the electrospray ion source polarity between positive and negative modes in a single run. The calibration curves of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid were linear over the concentration ranges of 5-2000, 5-2000, 0.5-200, 0.5-200, 0.25-100, 0.25-100, 0.025-10 and 0.50-200 ng mL(-1) , respectively. The intra- and inter-assay precisions and accuracies were <11.6 and 91.9-108.2%, respectively, for all analytes. Matrix effects for all analytes were between 88.2 and 114.2%. Stability testing showed that all analytes were stable in plasma at 24 °C for 3 h, at 4 °C for 24 h, after three freeze-thaw cycles, and at -80 °C for 15 days. The method was successfully applied to an in vivo study evaluating the pharmacokinetics of multiple nonvolatile compounds following intragastric administration of Longhu Rendan pills to rats. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26613237

  14. Bioefficacy of tea catechins encapsulated in casein micelles tested on a normal mouse cell line (4D/WT) and its cancerous counterpart (D/v-src) before and after in vitro digestion.

    Science.gov (United States)

    Haratifar, Sanaz; Meckling, Kelly A; Corredig, Milena

    2014-06-01

    Numerous studies have demonstrated that tea catechins form complexes with milk proteins, especially caseins. Much less work has been conducted to understand the metabolic conversions of tea-milk complexes during gastro-duodenal digestion. The objective of this study was to determine the significance of this association on the digestibility of the milk proteins and on the bioaccessibility of the tea polyphenol epigallocatechin gallate (EGCG). An in vitro digestion model mimicking the gastric and duodenal phases of the human gastrointestinal tract was employed to follow the fate of the milk proteins during digestion and determine the bioefficacy of EGCG isolated or encapsulated with the caseins. The samples, before and after digestion, were tested using two parallel colonic epithelial cell lines, a normal line (4D/WT) and its cancerous transformed counterpart (D/v-src). EGCG caused a decrease in proliferation of cancer cells, while in normal cells, neither isolated nor encapsulated EGCG affected cell proliferation, at concentrations casein micelles are an appropriate delivery system for polyphenols. PMID:24686838

  15. THE COMBINED EFFECTS OF CATECHINS AND CAFFEINE ON CELLULAR PROLIFERATION AND LIPID METABOLISM IN 3T3-L1 CELLS%儿茶素和咖啡碱组合对3T3-L1细胞增殖及脂肪代谢的影响

    Institute of Scientific and Technical Information of China (English)

    郑国栋; 邱阳阳; 张清峰; 徐峰

    2013-01-01

    目的 研究对儿茶素和咖啡碱对3T3-L1细胞的增殖及脂肪代谢的影响.方法 采用四甲基偶氮唑盐比色法(MTT)检测对3T3-L1细胞增殖的影响;3T3-L1细胞诱导分化8d后,对各组细胞进行油红O染色并测定细胞内甘油三酯(TG)含量;细胞分化12d后,添加儿茶素和咖啡碱组合或同时添加去甲肾上腺素(NA)作用24h,分析各组细胞内脂肪分解.结果 儿茶素能明显抑制3T3-L1细胞的增殖;儿茶素和咖啡碱组合能明显抑制3T3-L1细胞分化后,细胞内TG的沉积,且在相同儿茶素浓度下,咖啡碱浓度越高抑制效果越明显.咖啡碱明显提高NA诱导成熟脂肪细胞脂解的能力,且呈剂量效应关系.结论 儿茶素和咖啡碱组合能够抑制脂肪细胞增殖和甘油三酯积聚,咖啡碱促进激素诱导脂肪细胞中脂肪分解.%Objective To investigate the combined effects of catechins and caffeine on cells proliferation and lipid metabolism in 3T3-L1 cells. Method MTT colorimetry was used to detect the effects of catechins and caffeine combination on the proliferation of 3T3-L1 cells. The differentiation of 3T3-L1 cells was induced for 8 d, then the adipocytes were stained by oil Red O, and the level of triglyceride (TG) was measured. The lipolytic effect of catechins and caffeine combination in presence or absence of noradrenaline (NA) for 24 h on 3T3-L1 cells was analyzed on the 12 th day after differentiation. Results Catechins significantly inhibited 3T3-L1 cells proliferation. Catechins and caffeine combination remarkably decreased TG accumulation after differentiation of 3T3-L1 cells, and the higher caffeine concentration was better when combined with the same catechins dose. Caffeine significantly improved NA-induced lipolysis in mature adipocytes. Conclusion Catechins and caffeine combination might inhibit cells proliferation and TG accumulation in 3T3-L1 cells. Caffeine promotes hormone-induced lipolysis in adipocytes.

  16. Characterization of polyphenol oxidase from honey peach using (+)-catechin as substrate%以儿茶素为底物研究水蜜桃多酚氧化酶的酶学特性

    Institute of Scientific and Technical Information of China (English)

    龚森康; 刘亮; 武萌萌; 郑世博

    2012-01-01

    以水蜜桃中主要的酚类物质儿茶素为底物,研究水蜜桃多酚氧化酶的酶学特性。研究结果表明,该酶的最适反应温度为40℃、最适反应pH值为6.5;PPO的热稳定性结果表明,60℃以下时,水蜜桃中PPO较稳定,高于70℃,其稳定性迅速下降;pH值稳定性研究结果表明,酶在pH6.0以下及9.0以上时不稳定,pH为6.0~8.0时稳定;酶抑制学研究表明,谷胱甘肽和L-半胱氨酸在较低浓度时就能对此酶促反应产生较好的抑制作用,而氟化钠和氯化钠要在高浓度下才能对酶促氧化产生抑制作用,其抑制作用由强到弱的顺序为:L-Cys〉GSH〉NaF〉NaCl。%Polyphenol oxidase(PPO) from honey peach had been characterized using (+)-catechin which was the major endogenous polyphenol in honey peach as substrate. The results indicated that the optimum temperature was 40℃. For thermostability studies, the enzyme was stable below 60 ℃and the enzyme activity decreased significantly above 70 %. The results also showed that the optimum pH was 6.5 and the enzyme was stable in the pH range 6.0-8.0. The inhibition studies indicated that L-cysteine and glutathione were more effective for the inhibition of peach PPO, while NaF and NaCl inhibited moderately, especially NaCI. In conclusion, the inhibition effects on the enzyme activity were as follow: L-Cys〉GSH〉NaF〉NaCl.

  17. Evaluation of Chromogenic Reaction Ability of Hydrochloric Acid (Sulfuric Acid)-vanillin by the Colorimetry for Determining Tea Catechins Aggregates%茶叶儿茶素总量比色测定的盐酸(硫酸)香草醛显色反应能力评价

    Institute of Scientific and Technical Information of China (English)

    单虹丽; 卿钰; 杜晓; 刘东娜

    2012-01-01

    Chromogenic reaction level of catechins from the green tea and the black tea with hydrochloric acid (sulfuric acid-vanillin)-vanillin was determined in this paper. By determining and comparing the reaction coefficient, accuracy and precision, the color reaction ability of catechins reacted with acid vanillin was evaluated. The results showed that the reaction system was sensitive to catechins with a high linear correlation(R2HA =0.9976 ±0.001 4, R2SA =0.9978 ±0.001 8). It was also seen that the chromogenic reaction coefficients from both systems were less than the Roberts coefficient (145.68) obtained from the empirical formula for calculating catechins aggregates. The recoveries from both system were more than 94.22 % and all the variation coefficient of precision were less than 0.08 %. This showed that both systems could determinate tea catechins aggregates. The chromogenic capability of tea catechins from different sources with acid-Vanillin was very different from each other (F = 37. 434 > F0.01(1,5) =6.61). This results showed that two kinds of reaction systems could objectively reflect tea catechins aggregates. However, both recoveries and variation coefficient from the empirical formula were instable and the total catechins aggregates was higher than the reality.%测定了茶叶儿茶素及绿茶、红茶中的儿茶素与盐酸(硫酸)-香草醛的显色反应水平,通过对反应系数、准确度、精密度测定和比较,评价了儿茶素与酸性香草醛的显色反应能力.结果表明:两种酸性体系对儿茶素反应灵敏,且呈高度线性相关(R2盐酸=0.9976±0.0014,R2硫酸=0.9978±0.0018);显色反应系数上,盐酸法为34.77±10.00(绿茶)、83.83±20.13(红茶);硫酸法为39.65±8.97(绿茶)、86.68±19.87(红茶),均低于茶叶儿茶素总量经验计算公式中Roberts系数(145.68).盐酸-香草醛显色反应体系的回收率为94.22%±3.33%(绿茶)、99.71%±1.39%(红茶),精密度的变异系数为0.08

  18. 祁门红茶加工中氨基酸和儿茶素快速检测模型建立%Rapid and Dynamic Determination Models of Amino Acids and Catechins Concentrations during the Processing Procedures of Keemun Black Tea

    Institute of Scientific and Technical Information of China (English)

    宁井铭; 颜玲; 张正竹; 韦玲冬; 李露青; 方骏婷; 黄财旺

    2015-01-01

    Tea is one of the most popular beverages in the world .For the contribution to the taste and healthy functions of tea , amino acids and catechins are important components .Among different kinds of black teas in the world ,Keemun black tea has the famous and specific fragrance ,“Keemun aroma” .During the processing procedure of Keemun black tea ,the contents of amino acids and catechins changed greatly ,and the differences of these concentrations during processing varied significantly .However , a rapid and dynamic determination method during the processing procedure was not existed up to now .In order to find out a rap-id determination method for the contents of amino acids and catechins during the processing procedure of Keemun black tea ,the materials of fresh leaves ,withered leaves ,twisted leaves ,fermented leaves ,and crude tea (after drying ) were selected to acquire their corresponding near infrared spectroscopy and obtain their contents of amino acids and catechins by chemical analysis meth-od .The original spectra data were preprocessed by the Standard Normal Variate Transformation (SNVT ) method .And the model of Near Infrared (NIR) spectroscopy with the contents of amino acids and catechins combined with Synergy Interval Par-tial Least squares (Si-PLS) was established in this study .The correlation coefficients and the cross validation root mean square error are treated as the efficient indexes for evaluating models .The results showed that the optimal prediction model of amino acids by Si-PLS contained 20 spectral intervals combined with 4 subintervals and 9 principal component factors .The correlation coefficient and the root mean square error of the calibration set were 0.955 8 and 1.768 ,respectively ;the correlation coefficient and the root mean square error of the prediction set were 0.949 5 and 2.16 ,respectively .And the optimal prediction model of catechins by Si-PLS contained 20 spectral intervals combined with 3 subintervals and 10

  19. A method for fast determination of epigallocatechin gallate (EGCG, epicatechin (EC, catechin (C and caffeine (CAF in green tea using HPLC Método rápido para determinação de galato de epigalocatequina (EGCG, epicatequina (EC, catequina (C e cafeína (CAF em chá verde usando CLAE

    Directory of Open Access Journals (Sweden)

    Samuel T. Saito

    2006-06-01

    Full Text Available Tea has been considered a medicine and a healthy beverage since ancient times, but recently it has received a great deal of attention because of its antioxidant properties. Green tea polyphenols have demonstrated to be an effective chemopreventive agent. Recently, investigators have found that EGCG, one of the green tea catechins, could have anti-HIV effects when bound to CD4 receptor. Many factors can constitute important influences on the composition of tea, such as species, season, age of the leaf, climate, and horticultural practices (soil, water, minerals, fertilizers. This paper presents an HPLC analytical methodology development, using column RP-18 and mobile phase composed by water, acetonitrile, methanol, ethyl acetate, glacial acetic acid (89:6:1:3:1 v/v/v/v/v for simultaneous determination and quantification of caffeine (CAF, catechin (C, epicatechin (EC and epigallocatechin gallate (EGCG in samples of Camellia sinensis (green tea grown in Brazil and harvested in spring, in summer and in autumn, in comparison to Brazilian black tea, to samples of Japanese and Chinese green tea and to two standardized dry extracts of green tea. The method has been statistically evaluated and has proved to be adequate to qualitative and quantitative determination of the samples.O chá vem sendo considerado uma bebida saudável e com propriedades medicinais desde tempos bem remotos, mas recentemente tem ganhado grande interesse no meio científico devido a suas atividades como antioxidante. Os polifenóis do chá verde vêm demonstrando possuir atividades quimiopreventivas. Recentemente, pesquisadores descobriram que o EGCG, a principal catequina do chá verde, poderia ter efeito anti-HIV quando acoplado ao receptor CD4. Muitos fatores podem influenciar de forma significativa na composição do chá, como sua espécie, estação que foi colhida, idade da folha, clima e técnicas de cultura (solo, irrigação e fertilizantes. Este artigo vem apresentar

  20. Aspectos funcionais das catequinas do chá verde no metabolismo celular e sua relação com a redução da gordura corporal Functional aspects of green tea catechins in the cellular metabolism and their relationship with body fat reduction

    Directory of Open Access Journals (Sweden)

    Renata da Costa Lamarão

    2009-04-01

    Full Text Available O chá é uma bebida amplamente utilizada, perdendo apenas para a água como a bebida mais consumida no mundo. O chá verde é rico em polifenóis, principalmente catequinas. Entre uma variedade de efeitos benéficos à saúde atribuídos ao consumo do chá verde, grande atenção tem sido focalizada no seu efeito na redução da gordura corporal. Este estudo tem como objetivo apresentar uma descrição dos estudos com o chá verde e/ou seus compostos bioativos relacionados à biologia celular, estudos experimentais e epidemiológicos associados ao metabolismo lipídico e à redução da gordura corporal. Galato de epigalocatequina é o principal composto bioativo presente no chá verde e seus efeitos anti-obesidade estão sendo investigados. Tais efeitos estão associados a diversos mecanismos bioquímicos e fisiológicos, dentre eles podem-se destacar a estimulação do metabolismo lipídico pela combinação da ingestão de catequinas e a prática de exercícios físicos regulares. Apesar do efeito promissor do chá verde e seus compostos bioativos no tratamento da obesidade, estudos clínicos controlados devem ser conduzidos. Finalmente, um plano alimentar adequado associado à prática regular de atividade física constitui a principal ferramenta para a prevenção da obesidade e de suas comorbidades.The use of tea is widespread, second only to water in worldwide consumption. Green tea is rich in polyphenols, mainly catechins. Among a variety of beneficial health effects attributed to the consumption of the green tea, much attention has been given to its ability to reduce body fat. This study has the objective of presenting a description of the studies of green tea and/or its bioactive compounds related to cell biology and of experimental and epidemiological studies associated with lipid metabolism and the reduction of body fat. Epigallocatechin gallate is the main bioactive compound present in green tea and its anti-obesity effects are

  1. Inhibition of Pectin Methyl Esterase Activity By Green Tea Catechins

    OpenAIRE

    Sagi, Irit; Lewis, Kristin; Tworowski, Dmitry; Shahar, Chen; Selzer, Tzvia

    2008-01-01

    Pectin methyl esterases (PMEs) and their endogenous inhibitors are involved in the regulation of many processes in plant physiology, ranging from tissue growth and fruit ripening to parasitic plant haustorial formation and host invasion. Thus, control of PME activity is critical for enhancing our understanding of plant physiological processes and regulation. Here we report on the identification of epigallocatechin gallate (EGCG), a green tea component, as a natural inhibitor for pectin ...

  2. Oligomerization and hydroxylation of green tea catechins by oxidative enzymes

    NARCIS (Netherlands)

    Verloop, J.W.

    2016-01-01

    Black teas are known for their characteristic brown colour, bitter taste and astringent mouth feel. These sensory characteristics are mainly influenced by the phenolic oxidation products present in black tea. The oxidation of phenolics from green tea leaves during black tea manufacturing is an uncon

  3. Modulation of signal transduction by tea catechins and related phytochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Masahito [Herbert Irving Comprehensive Cancer Center and Department of Medicine, Columbia University Medical Center, HHSC-1509, 701 West 168 Street, NY 10032-2704 (United States); Weinstein, I. Bernard [Herbert Irving Comprehensive Cancer Center and Department of Medicine, Columbia University Medical Center, HHSC-1509, 701 West 168 Street, NY 10032-2704 (United States)]. E-mail: ibw1@columbia.edu

    2005-12-11

    Epidemiologic studies in human populations and experimental studies in rodents provide evidence that green tea and its constituents can inhibit both the development and growth of tumors at a variety of tissue sites. In addition, EGCG, a major biologically active component of green tea, inhibits growth and induces apoptosis in a variety of cancer cell lines. The purpose of this paper is to review evidence that these effects are mediated, at least in part, through inhibition of the activity of specific receptor tyrosine kinases (RTKs) and related downstream pathways of signal transduction. We also review evidence indicating that the antitumor effects of the related polyphenolic phytochemicals resveratrol, genistein, curcumin, and capsaicin are exerted via similar mechanisms. Some of these agents (EGCG, genistein, and curcumin) appear to directly target specific RTKs, and all of these compounds cause inhibition of the activity of the transcription factors AP-1 and NF-{kappa}B, thus inhibiting cell proliferation and enhancing apoptosis. Critical areas of future investigation include: (1) identification of the direct molecular target(s) of EGCG and related polyphenolic compounds in cells; (2) the in vivo metabolism and bioavailability of these compounds; (3) the ancillary effects of these compounds on tumor-stromal interactions; (4) the development of synergistic combinations with other antitumor agents to enhance efficacy in cancer prevention and therapy, and also minimize potential toxicities.

  4. Is (-)-Catechin a "Novel Weapon" of Spotted Knapweed (Centaurea stoebe)?

    Science.gov (United States)

    The “novel weapons” hypothesis states that some invasive weed species owe part of their success as invaders to allelopathy mediated by allelochemicals that are new to the native species. Presumably, no resistance has evolved among the native species to this new allelochemical (i.e. the novel weapon...

  5. Modulation of signal transduction by tea catechins and related phytochemicals

    International Nuclear Information System (INIS)

    Epidemiologic studies in human populations and experimental studies in rodents provide evidence that green tea and its constituents can inhibit both the development and growth of tumors at a variety of tissue sites. In addition, EGCG, a major biologically active component of green tea, inhibits growth and induces apoptosis in a variety of cancer cell lines. The purpose of this paper is to review evidence that these effects are mediated, at least in part, through inhibition of the activity of specific receptor tyrosine kinases (RTKs) and related downstream pathways of signal transduction. We also review evidence indicating that the antitumor effects of the related polyphenolic phytochemicals resveratrol, genistein, curcumin, and capsaicin are exerted via similar mechanisms. Some of these agents (EGCG, genistein, and curcumin) appear to directly target specific RTKs, and all of these compounds cause inhibition of the activity of the transcription factors AP-1 and NF-κB, thus inhibiting cell proliferation and enhancing apoptosis. Critical areas of future investigation include: (1) identification of the direct molecular target(s) of EGCG and related polyphenolic compounds in cells; (2) the in vivo metabolism and bioavailability of these compounds; (3) the ancillary effects of these compounds on tumor-stromal interactions; (4) the development of synergistic combinations with other antitumor agents to enhance efficacy in cancer prevention and therapy, and also minimize potential toxicities

  6. Inhibition of FLT3 expression by green tea catechins in FLT3 mutated-AML cells.

    Directory of Open Access Journals (Sweden)

    Bui Thi Kim Ly

    Full Text Available Acute myeloid leukemia (AML is a heterogeneous disease characterized by a block in differentiation and uncontrolled proliferation. FLT3 is a commonly mutated gene found in AML patients. In clinical trials, the presence of a FLT3-ITD mutation significantly correlates with an increased risk of relapse and dismal overall survival. Therefore, activated FLT3 is a promising molecular target for AML therapies. In this study, we have shown that green tea polyphenols including (--epigallocatechin-3-gallate (EGCG, (--epigallocatechin (EGC, and (--epicatechin-3-gallate (ECG suppress the proliferation of AML cells. Interestingly, EGCG, EGC and ECG showed the inhibition of FLT3 expression in cell lines harboring FLT3 mutations. In the THP-1 cells harboring FLT3 wild-type, EGCG showed the suppression of cell proliferation but did not suppress the expression of FLT3 even at the concentration that suppress 100% cell proliferation. Moreover, EGCG-, EGC-and ECG-treated cells showed the suppression of MAPK, AKT and STAT5 phosphorylation. Altogether, we suggest that green tea polyphenols could serve as reagents for treatment or prevention of leukemia harboring FLT3 mutations.

  7. The protective effect of green tea catechins on ketamine-induced cystitis in a rat model

    OpenAIRE

    Mei-Yu Jang; Yi-Lun Lee; Cheng-Yu Long; Chung-Hwan Chen; Shu-Mien Chuang; Hsiang-Ying Lee; Jung-Tsung Shen; Wen-Jeng Wu; Yung-Shun Juan

    2015-01-01

    Objective: To investigate the protective effect of green tea epigallocatechin gallate (EGCG) on long-term ketamine-induced ulcerative cystitis (KIC) using a ketamine addiction rat model. Materials and methods: Thirty Sprague-Dawley rats were divided into three groups which received saline, ketamine (25 mg/kg/d), or ketamine combined with EGCG (10 μM/kg) for a period of 28 days. In each group, cystometry and a metabolic cage micturition pattern study were performed weekly. Masson's trichrom...

  8. Effects of dietary catechins and proanthocyanidins on zinc homeostasis in hepatic cells

    OpenAIRE

    Quesada, Isabel Maria

    2010-01-01

    Les catequines i els seus polímers, les procianidines, són flavonoids presents en hortalissesi fruits amb efectes beneficiosos sobre la salut. Actuen com a antioxidants segrestantespècies reactives d'oxigen (ROS) i quelant els metalls ferro i coure. També es comportencom a molècules senyalitzadores, modulant múltiples vies de senyalització i metabòliques il'expressió gènica, incloent-hi la d'enzims antioxidants. Resultats previs del Grup de Recercaen Nutrigenòmica mostren que una dosi oral ag...

  9. Bactericidal activity of green tea extracts: the importance of catechin containing nano particles

    OpenAIRE

    Judy Gopal; Manikandan Muthu; Diby Paul; Doo-Hwan Kim; Sechul Chun

    2016-01-01

    When we drink green tea infusion, we believe we are drinking the extract of the green tea leaves. While practically each tea bag infused in 300 mL water contains about 50 mg of suspended green tea leaf particles. What is the role of these particles in the green tea effect is the objective of this study. These particles (three different size ranges) were isolated via varying speed centrifugation and their respective inputs evaluated. Live oral bacterial samples from human volunteers have been ...

  10. Validation of the technique to assessment of tablets Catechin from Rhizophora mangle L. by HPLC

    International Nuclear Information System (INIS)

    Authors made the high-performance liquid chromatography method validation to the quantitative assessment of cathechin as a marker substance in tablets obtained from the bark of Rhizophora mangle L. dry extract used in gastroduodenal ulcers treatment. Considering that this method as such is classified to quantitative assessment of the major compound or active ingredient in formulae or raw material, the following parameters were assessed: linearity, accuracy, sensitivity and precision expressed in its two ways: repetition and intermediate precision. Results obtained showed that this method is reliable allowing the compound assessment in presence of other substances, including excipients and auxiliary substances and to detect the presence of degradation products. Also, the statistical processing of results evidenced the linearity, precision, sensitivity and accuracy of this method

  11. The Case Against (-)-Catechin Involvement in Allelopathy in Centaurea stoebe (spotted knapweed)

    Science.gov (United States)

    Proving allelopathic chemical interference is a daunting endeavor, in that production and movement of a phytotoxin from a donor plant to a receiving plant must be demonstrated in the substrate in which the plants grow, which is usually a complex soil matrix. The soil levels or soil flux levels of th...

  12. Green tea catechin inhibits fatty acid synthase without stimulating carnitine Palmitoyltransferase-1 or inducing weight loss in experimental animals

    OpenAIRE

    Puig i Miquel, Teresa; Relat Pardo, Joana; Marrero González, Pedro F.; Haro Bautista, Diego; Brunet, Joan; Colomer Bosch, Ramón

    2008-01-01

    Background: The enzyme fatty acid synthase (FASN) is highly expressed in many human carcinomas and its inhibition is cytotoxic to human cancer cells. The use of FASN inhibitors has been limited until now by anorexia and weight loss, which is associated with the stimulation of fatty acid oxidation. Materials and Methods: The in vitro effect of (-)-epigallocatechin-3-gallate (EGCG) on fatty acid metabolism enzymes, on apoptosis and on cell signalling was evaluated. In vivo, the effect of EGCG o...

  13. Stability of catechins in green tea nutraceutical products: application of solid phase extraction-thin layer chromatography densitometry.

    Science.gov (United States)

    Abd-Elsalam, Heba-Alla H; Al-Ghobashy, Medhat A; Zaazaa, Hala E; Ibrahim, Mohamed A

    2014-08-01

    Epigallocatechin gallate (EGCG) is a powerful antioxidant and commonly used nutraceutical. Accelerated stability of EGCG in tablet formulations was investigated. LLE and SPE were employed for sample clean-up and enrichment of EGCG over caffeine. Samples were analysed after spiking with fixed concentration of gallic acid (GA), in order to verify reproducibility of analysis. A TLC-densitometric assay was developed and validated for determination of % loss EGCG. EGCG, GA and caffeine were resolved with Rf values 0.54, 0.69 and 0.80, respectively. LC-MS/MS was used to verify identity and purity of the EGCG band. Determination was carried out over a concentration range of 0.50-5.00μg/band and 0.20-2.40μg/band for GA and caffeine, respectively. Results showed significant reduction in EGCG content after one, three and six months: 24.00%, 28.00% and 52.00% respectively. Results continue to demonstrate that stability of nutraceutical products should be investigated in-depth using industry-oriented protocols before granting marketing authorisation. PMID:24629943

  14. The Powdering Process with a Set of Ceramic Mills for Green Tea Promoted Catechin Extraction and the ROS Inhibition Effect

    OpenAIRE

    Kouki Fujioka; Takeo Iwamoto; Hidekazu Shima; Keiko Tomaru; Hideki Saito; Masaki Ohtsuka; Akihiro Yoshidome; Yuri Kawamura; Yoshinobu Manome

    2016-01-01

    For serving green tea, there are two prominent methods: steeping the leaf or the powdered leaf (matcha style) in hot water. The purpose of the present study was to reveal chemical and functional differences before and after the powdering process of green tea leaf, since powdered green tea may contribute to expanding the functionality because of the different ingesting style. In this study, we revealed that the powdering process with a ceramic mill and stirring in hot water increased the avera...

  15. Green tea catechin EGCG suppresses T cell-mediated function through inhibiting cell division and reducing cell survival

    Science.gov (United States)

    Green tea and its active ingredient, epigallocatechin-3-gallate (EGCG), have been indicated to have varied health benefits. Given the rapid increase in consumption of green tea, particularly the high intakes from supplements, its potential risks need to be evaluated. To date, little is known about t...

  16. Hematopoietic-supportive effect of (2S, 3R)-ent-catechin on marrow-depressed mice

    Institute of Scientific and Technical Information of China (English)

    CHEN Yi-hong; WANG Dong-xiao; LIU Ping; CHEN Ruo-yun; CHEN Meng-li; CHENG Liu-fang; YIN Jian-fen; CHEN Gui-yun

    2005-01-01

    @@ Hematopoiesis is an active process of cell proliferation, differentiation and release. It is the process during which hematopoietic stem cells (HSCs) proliferate and differentiate to mature blood cells under the effect of hemetopoietic growth factors (HGFs) in certain hematopoietic microenvironment. HSCs are sources of hematopoiesis of a body that can self-renew, differentiate to blood cells of every lineage and maintain the constancy of them. As the major tissue of hematopoiesis bone marrow is filled with all kinds of blood cells in various developmental stages. Under the normal conditions, the ordered proliferation and differentiation of hematopoietic stem cells/hematopoietic progenitor cells (HSC/HPC) depend on the regulation of cytokine network.

  17. Functional analysis of Flavonoid 3′,5′-hydroxylase from Tea plant (Camellia sinensis): critical role in the accumulation of catechins

    OpenAIRE

    Wang, Yun-Sheng; Xu, Yu-Jiao; Gao, Li-Ping; Yu, Oliver; Wang, Xin-Zhen; He, Xiu-Juan; Jiang, Xiao-Lan; Liu, Ya-Jun; Xia, Tao

    2014-01-01

    Background Flavonoid 3′,5′-hydroxylase (F3′5′H), an important branch point enzyme in tea plant flavan-3-ol synthesis, belongs to the CYP75A subfamily and catalyzes the conversion of flavones, flavanones, dihydroflavonols and flavonols into 3′,4′,5′-hydroxylated derivatives. However, whether B-ring hydroxylation occurs at the level of flavanones and/or dihydroflavonols, in vivo remains unknown. Results The Camellia sinensis F3′5′H (CsF3′5′H) gene was isolated from tea cDNA library. Expression ...

  18. Simultaneous determination of hydroxycinnamates and catechins in human urine samples by column switching liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry

    DEFF Research Database (Denmark)

    Nielsen, Salka E.; Sandström, B.

    2003-01-01

    atmospheric pressure chemical ionization (APCI) MS using single ion monitoring (SIM) in negative mode. Linear calibration graphs were achieved in the dynamic range of 10-1000 ng/ml urine. The inter- and intraassay coefficients of variation (C.V.%) for the analysis of the four compounds in quality control...... urine samples were between 7.8 and 10.9, n=17 (reproducibility), and the repeatability of the assay was between 2.5 and 5.0% (n = 12). Analyses of urine samples from a human dietary intervention study with intake of 600 g of fruits and vegetables were demonstrated. To our knowledge, this is the first...

  19. In vitro effects of myricetin, morin, apigenin, (+)-taxifolin, (+)-catechin, (−)-epicatechin, naringenin and naringin on cytochrome b5 reduction by purified NADH-cytochrome b5 reductase

    International Nuclear Information System (INIS)

    Highlights: • We assessed inhibitory effects of 8 dietary flavonoids on cytochrome b5 reduction by purified NADH-cytochrome b5 reductase. • The flavonol myricetin was the most potent in inhibiting cytochrome b5 reduction with an IC50 value of 0.35 μM. • We investigated kinetics of myricetin-induced inhibition in detail. • We explored the structure–inhibitory activity relationship of compounds. • Modulation of cytochrome b5 reduction indicates a potential for myricetin to lead to some food–drug/xenobiotic interactions. - Abstract: The microsomal NADH-dependent electron transport system consisting of cytochrome b5 reductase and cytochrome b5 participates in a number of physiologically important processes including lipid metabolism as well as is involved in the metabolism of various drug and xenobiotics. In the present study, we assessed the inhibitory effects of eight dietary flavonoids representing five distinct chemical classes on cytochrome b5 reduction by purified cytochrome b5 reductase. From the flavonoids tested, myricetin was the most potent in inhibiting cytochrome b5 reduction with an IC50 value of 0.35 μM. Myricetin inhibited b5 reductase noncompetitively with a Ki of 0.21 μM with respect to cofactor NADH, and exhibited a non-linear relationship indicating non-Michaelis–Menten kinetic binding with respect to cytochrome b5. In contrast to the potent inhibitory activity of myricetin, (+)-taxifolin was found to be a weak inhibitor (IC50 = 9.8 μM). The remaining flavonoids were inactive within the concentration range tested (1–50 μM). Analysis of structure–activity data suggested that simultaneous presence of three OH groups in ring B is a primary structural determinant for a potent enzyme inhibition. Our results suggest that inhibition of the activity of this system by myricetin or myricetin containing diets may influence the metabolism of therapeutic drugs as well as detoxification of xenobiotics

  20. 'Benifuuki' Green Tea Containing O-Methylated Catechin Reduces Symptoms of Japanese Cedar Pollinosis: A Randomized, Double- Blind, Placebo-Controlled Trial

    Directory of Open Access Journals (Sweden)

    Sawako Masuda

    2014-01-01

    Conclusions: 'Benifuuki' green tea containing a large amount of O-methylated EGCG reduced the symptoms of JCP and has potential as a complementary/alternative medicine for treating seasonal allergic rhinitis.

  1. Pharmacokinetic and Chemoprevention Studies on Tea in Humans

    OpenAIRE

    Chow, H-H. Sherry; Hakim, Iman A.

    2011-01-01

    Green tea and its major polyphenols constituents, tea catechins, have been shown to have many health benefits including cancer prevention. Tea catechins and tea catechin metabolites/catabolites are bioavailable in the systemic circulation after oral intake of green tea or green tea catechins. The metabolites/catabolites identified in humans include glucuronide/sulfate conjugates, methylated tea catechin conjugates, and microflora-mediated ring fission products and phenolic acid catabolites. P...

  2. Control of Clostridium perfringens Spores by Green Tea Leaf Extracts During Cooling of Cooked Ground Beef, Chicken, and Pork

    Science.gov (United States)

    We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (GTL; 141 mg total catechins/g of green tea extract) and high (GTE; 697 mg total catechins/g of extract) catechin levels during abusive chilling of retail cooked ground beef, ...

  3. HPLC-DAD-MS/MS analysis of purine alkaloids and tea polyphenols in young leaves of Yinghong 1, Yinghong 9 and Qimen cultivars

    OpenAIRE

    J. Chen; Lu, J; Wang, D; Miao, A; D. Yang

    2009-01-01

    Using the HPLC-DAD-MS/MS method, two purine alkaloids, seven catechins, and two non-catechin type of polyphenols were identified in young leaves of Yinghong 1, Yinghong 9 and Qimen cultivars mainly made for black tea. According to the quantitative results, the contents of catechins in the leaves of Yinghong 1 and Qimen are similar, while Yinghong 9 is quite different, with ECG higher than EGCG.

  4. Synthesis and Properties of Biobased Epoxy Resins. Part 1. Glycidylation of Flavonoids by Epichlorohydrin

    OpenAIRE

    Nouailhas, Hélène; Aouf, Chahinez; Le Guernevé, Christine; CAILLOL, Sylvain; Boutevin, Bernard; Fulcrand-Hoh, Helene,

    2011-01-01

    Biobased epoxy resins were synthesized from a catechin molecule, one of the repetitive units in natural flavonoid biopolymers also named condensed tannins. The reactivity of catechin toward epichlorohydrin to form glycidyl ether derivatives was studied using two model compounds, resorcinol and 4-methylcatechol, which represent the A and B rings of catechin, respectively. These model molecules clearly showed differences in reactivity upon glycidylation, explaining the results found with catech...

  5. Tea Polyphenols Regulate Key Mediators on Inflammatory Cardiovascular Diseases

    OpenAIRE

    Jun-ichi Suzuki; Mitsuaki Isobe; Ryuichi Morishita; Ryozo Nagai

    2009-01-01

    Tea polyphenols known as catechins are key components with many biological functions, including anti-inflammatory, antioxidative, and anticarcinogenic effects. These effects are induced by the suppression of several inflammatory factors including nuclear factor-kappa B (NF- B). While these characteristics of catechins have been well documented, actions of catechins as mediators on inflammation-related cardiovascular diseases have not yet been well investigated. In this article, we reviewed ...

  6. Green tea: A boon for periodontal and general health

    OpenAIRE

    Chatterjee, Anirban; Saluja, Mini; Agarwal, Gunjan; Alam, Mahtab

    2012-01-01

    Green tea is particularly rich in health-promoting flavonoids (which account for 30% of the dry weight of a leaf), including catechins and their derivatives. The most abundant catechin in green tea is epigallocatechin-3-gallate, which is thought to play a pivotal role in the green tea's anticancer and antioxidant effects. Catechins should be considered right alongside of the better-known antioxidants like vitamins E and C as potent free radical scavengers and health-supportive for this reason...

  7. Beneficial effects of green tea: A literature review

    OpenAIRE

    Kuttan Ramadasan; Thambi Priya T; Chacko Sabu M; Nishigaki Ikuo

    2010-01-01

    Abstract The health benefits of green tea for a wide variety of ailments, including different types of cancer, heart disease, and liver disease, were reported. Many of these beneficial effects of green tea are related to its catechin, particularly (-)-epigallocatechin-3-gallate, content. There is evidence from in vitro and animal studies on the underlying mechanisms of green tea catechins and their biological actions. There are also human studies on using green tea catechins to treat metaboli...

  8. Divergent antiviral effects of bioflavonoids on the hepatitis C virus life cycle

    Energy Technology Data Exchange (ETDEWEB)

    Khachatoorian, Ronik, E-mail: RnKhch@ucla.edu [Molecular Biology Interdepartmental Ph.D. Program (MBIDP), Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Arumugaswami, Vaithilingaraja, E-mail: VArumugaswami@mednet.ucla.edu [Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Department of Surgery, Regenerative Medicine Institute at Cedars-Sinai Medical Center, Los Angeles, California, CA (United States); Raychaudhuri, Santanu, E-mail: SRaychau@ucla.edu [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Yeh, George K., E-mail: GgYeh@ucla.edu [Molecular Biology Interdepartmental Ph.D. Program (MBIDP), Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Molecular Biology Institute, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); Maloney, Eden M., E-mail: EMaloney@ucla.edu [Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, California, CA (United States); Wang, Julie, E-mail: JulieW1521@ucla.edu [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at University of California, Los Angeles, California, CA (United States); and others

    2012-11-25

    We have previously demonstrated that quercetin, a bioflavonoid, blocks hepatitis C virus (HCV) proliferation by inhibiting NS5A-driven internal ribosomal entry site (IRES)-mediated translation of the viral genome. Here, we investigate the mechanisms of antiviral activity of quercetin and six additional bioflavonoids. We demonstrate that catechin, naringenin, and quercetin possess significant antiviral activity, with no associated cytotoxicity. Infectious virion secretion was not significantly altered by these bioflavonoids. Catechin and naringenin demonstrated stronger inhibition of infectious virion assembly compared to quercetin. Quercetin markedly blocked viral translation whereas catechin and naringenin demonstrated mild activity. Similarly quercetin completely blocked NS5A-augmented IRES-mediated translation in an IRES reporter assay, whereas catechin and naringenin had only a mild effect. Moreover, quercetin differentially inhibited HSP70 induction compared to catechin and naringenin. Thus, the antiviral activity of these bioflavonoids is mediated through different mechanisms. Therefore combination of these bioflavonoids may act synergistically against HCV.

  9. Anti-cancer properties of green Tea Probed viaquantum mechanics calculations

    Directory of Open Access Journals (Sweden)

    Azin Chitsazan

    2015-03-01

    Full Text Available 10.13005/ojc/310147Tea, from the plant camellia sinensis, is consumed in different parts of the world as green, black or oolong tea. Among all of these, however, the most significant effects on human health have been observed with the consumption of green tea. Green tea contains polyphenols, which include flavanols, flavandiols, flavonoids, and phenolic acids. Most of the green tea polyphenols (GTPs are flavonols, commonly known as catechins. There are four kinds of catechins mainly find in green tea: epicatechin, epigallocatechin, epicatechin-3-gallate, and EGCG. Green tea catechins have demonstrated significant antioxidant, anticarcinogenic, anti-inflammatory, thermogenic, probiotic, and antimicrobial properties in numerous human, animal, and in vitro studies. In the present study, four type catechins of green tea were studied. For each catechin ab initio method was employed for calculations and related parameters were computed.

  10. Divergent antiviral effects of bioflavonoids on the hepatitis C virus life cycle

    International Nuclear Information System (INIS)

    We have previously demonstrated that quercetin, a bioflavonoid, blocks hepatitis C virus (HCV) proliferation by inhibiting NS5A-driven internal ribosomal entry site (IRES)-mediated translation of the viral genome. Here, we investigate the mechanisms of antiviral activity of quercetin and six additional bioflavonoids. We demonstrate that catechin, naringenin, and quercetin possess significant antiviral activity, with no associated cytotoxicity. Infectious virion secretion was not significantly altered by these bioflavonoids. Catechin and naringenin demonstrated stronger inhibition of infectious virion assembly compared to quercetin. Quercetin markedly blocked viral translation whereas catechin and naringenin demonstrated mild activity. Similarly quercetin completely blocked NS5A-augmented IRES-mediated translation in an IRES reporter assay, whereas catechin and naringenin had only a mild effect. Moreover, quercetin differentially inhibited HSP70 induction compared to catechin and naringenin. Thus, the antiviral activity of these bioflavonoids is mediated through different mechanisms. Therefore combination of these bioflavonoids may act synergistically against HCV.

  11. Aspectos funcionais das catequinas do chá verde no metabolismo celular e sua relação com a redução da gordura corporal Functional aspects of green tea catechins in the cellular metabolism and their relationship with body fat reduction

    OpenAIRE

    Renata da Costa Lamarão; Eliane Fialho

    2009-01-01

    O chá é uma bebida amplamente utilizada, perdendo apenas para a água como a bebida mais consumida no mundo. O chá verde é rico em polifenóis, principalmente catequinas. Entre uma variedade de efeitos benéficos à saúde atribuídos ao consumo do chá verde, grande atenção tem sido focalizada no seu efeito na redução da gordura corporal. Este estudo tem como objetivo apresentar uma descrição dos estudos com o chá verde e/ou seus compostos bioativos relacionados à biologia celular, estudos experime...

  12. Data Analysis of the Antioxidation of Tea Catechins from Big&Small Leaf Varieties in Plant Oil by SAS CENMOD Model%大小叶种儿茶素在植物油中抗氧化性数据的广义估计方程法的检验和分析

    Institute of Scientific and Technical Information of China (English)

    杨坤达

    2007-01-01

    在获得有关大小叶种儿茶素在植物油中的过氧化值数据后,怎样通过摆在人们面前的一大堆数据获得正确的结论,从而揭示一定的规律,并能展示其显著性和统计意义,SAS是目前流行的统计分析软件,应用广义估计方程(GENMOD)方法,可以从输出的信息中寻找统计上的参数值,来检验和证实结论可靠程度.

  13. THE FREE RADICAL SCAVENGING AND ANTI-HYPERGLYCEMIC ACTIVITIES OF VARIOUS GAMBIERS AVAILABLE IN INDONESIAN MARKET

    Directory of Open Access Journals (Sweden)

    Muhammad Hanafi

    2011-11-01

    Full Text Available Gambier (Uncaria gambier is known to have antioxidant properties, and some studies have attributed it to the presenceof polyphenols such as catechin. The objective of this study is to investigate the potential of various gambiers availablein Indonesian market as a scavenger of reactive free radicals and evaluate its anti-hyperglycemic activity as α-glucosidase inhibitor. Isolation of catechin was done by extraction method with technical grade of ethyl acetate assolvent. Analysis of catechin in the dried gambier extract was carried out with TLC method. The molecular weight andcontent of catechin of dried gambier extract was determined by analyzing its mass spectra and spectrophotometer,respectively. The free radical scavenging activity of catechin of the resultant extracts was measured by using 1,1-diphenyl-2-picrylhydrazyl (DPPH as stable free radical compound. The anti-hyperglycemic activity of catechin ofethyl acetate extracts was analyzed as α-glucosidase inhibitor. The result showed that various gambiers available in themarket are very active as antioxidant, indicated by IC50 of catechin of ethyl acetate extracts which were 4.6 to 18.2μg/mL for DPPH inhibition. The IC50 for α-glucosidase inhibition is ranged from 40.45 to 52.43 μg/mL, so they can beclassified as anti-diabetic.

  14. Delivery of tea polyphenols to the oral cavity by green tea leaves and black tea extract.

    Science.gov (United States)

    Lee, Mao-Jung; Lambert, Joshua D; Prabhu, Saileta; Meng, Xiaofeng; Lu, Hong; Maliakal, Pius; Ho, Chi-Tang; Yang, Chung S

    2004-01-01

    Catechins and theaflavins, polyphenolic compounds derived from tea (Camellia sinensis, fam. Theaceae), have been reported to have a wide range of biological activities including prevention of tooth decay and oral cancer. The present study was undertaken to determine the usefulness of green tea leaves and black tea extract for the delivery of catechins and theaflavins to the oral cavity. After holding either green tea leaves (2 g) or brewed black tea (2 g of black tea leaves in 100 ml) in the mouth for 2-5 min and thoroughly rinsing the mouth, high concentrations of catechins (C(max) = 131.0-2.2 micro M) and theaflavins (C(max) = 1.8-0.6 micro M) were observed in saliva in the 1st hour. Whereas there was significant interindividual variation in the peak levels of catechins and theaflavins, the overall kinetic profile was similar, with t(1/2) = 25-44 min and 49-76 min for catechins and theaflavins, respectively (average coefficient of variation in t(1/2) was 23.4%). In addition to the parent catechin and theaflavin peaks, five unidentified peaks were also observed in saliva after black tea treatment. Hydrolysis of theaflavin gallates, apparently by salivary esterases, was observed in vitro and in vivo. These results indicate that tea leaves can be used as a convenient, slow-release source of catechins and theaflavins and provide information for the possible use of tea in the prevention of oral cancer and dental caries. PMID:14744744

  15. Free-radical scavengers and antioxidants from Peumus boldus Mol. ("Boldo").

    Science.gov (United States)

    Schmeda-Hirschmann, G; Rodriguez, J A; Theoduloz, C; Astudillo, S L; Feresin, G E; Tapia, A

    2003-04-01

    The dry leaves of Peumus boldus (Monimiaceae) are used in infusion or decoction as a digestive and to improve hepatic complains. Preliminary assays showed free-radical scavenging activity in hot water extracts of boldo leaves, measured by the decoloration of a methanolic solution of the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH). Assay-guided isolation led to the active compounds. Catechin proved to be the main free-radical scavenger of the extracts. Lipid peroxidation in erythrocytes was inhibited by boldo extracts and fractions at 500 microg/ml with higher effect for the ethyl acetate soluble and alkaloid fractions. The IC50 for catechin and boldine in the lipid peroxidation test were 75.6 and 12.5 microg/ml, respectively. On the basis of dry starting material the catechin content in the crude drug was 2.25% while the total alkaloid calculated as boldine was 0.06%. The activity of boldine was six times higher than catechin in the lipid peroxidation assay. However, the mean catechin:total alkaloid content ratio was 37:1. The relative concentration of alkaloids and phenolics in boldo leaves and their activity suggest that free-radical scavenging effect is mainly due to catechin and flavonoids and that antioxidant effect is mainly related with the catechin content The high catechin content of boldo leaves and its bioactivity suggest that quality control of Boldo folium has to combine the analysis of catechin as well as their characteristic aporphine alkaloids. PMID:12747739

  16. Constituintes químicos das cascas do caule de Vochysia thyrsoidea Pohl. (Vochysiaceae) e avaliação das atividades citotóxica e inibitória frente as catepsinas B e K

    OpenAIRE

    Lorena Ramos Freitas de Sousa; Jame's A. da Silva; Paulo Cezar Vieira; Maísa Borges Costa; Mirley Luciene dos Santos; Aline Borba Sbardelotto; Cláudia do Ó Pessoa; Manoel Odorico de Moraes; Antônio Carlos Severo Menezes

    2014-01-01

    A new flavonoid, catechin-3-O-(3"-O-trans-cinnamoyl)-α-rhamnopyranoside, along with known compounds, catechin-3-O-α-rhamnopyranoside, 3-oxo-urs-12-en-28-oic acid, 2,4,6-trimethoxybenzoic acid, 2-butyl-D-fructofuranoside and 1-butyl-D-fructofuranoside, has been isolated from the stem bark of V. thyrsoidea. These compounds were assayed for inhibition of protease activity (cathepsins B and K) and against cancer cell lines. Catechin-3-O-(3"-O-trans-cinnamoyl)-α-rhamnopyranoside showed moderate in...

  17. Chemical constituents and antioxidant activity from leaves extracts of Terminalia fagifolia Mart. et Zucc; Constituintes quimicos e atividade antioxidante de extratos das folhas de Terminalia fagifolia Mart. et Zucc

    Energy Technology Data Exchange (ETDEWEB)

    Ayres, Mariane Cruz Costa; Chaves, Mariana H. [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Dept. de Quimica], e-mail: mariana@ufpi.br; Rinaldo, Daniel; Vilegas, Wagner; Vieira Junior, Gerardo Magela [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Quimica Organica

    2009-07-01

    Phytochemical investigation of ethanolic leaves extracts of T. fagifolia led to the isolation of (+)-catechin, sitosterol-3-O-{beta}-D-glucopyranoside, {alpha} and {beta} tocopherol, a mixture of lupeol, {alpha} and {beta}-amyrin, sitosterol and a mixture of glucoside flavonoids (CP-13). The structures of these compounds were identified by {sup 1}H and {sup 13}C NMR spectral analysis and comparison with literature data. Absolute configuration of the catechin was determinate by circular dichroism. Antioxidant activity (EC{sub 50}), evaluated by 2,2-diphenyl-1-picrylhidrazyl (DPPH) assay system, decreased in the order: (+)-catechin > hydroalcoholic fraction > CP-13 > aqueous fraction > EtOH extract. (author)

  18. Structure and antioxidant activity of phenolic compounds isolated from the edible fruits and stem bark of Harpephyllum caffrum.

    Science.gov (United States)

    Moodley, Roshila; Koorbanally, Neil A; Shahidul Islam, Md; Jonnalagadda, Sreekanth B

    2014-01-01

    Antioxidant activity in edible fruits is an important characteristic in the choice of fruits for human consumption, and has profound influence on nutrition and health. Two pharmacologically active triterpenoids, β-sitosterol and lupeol, and the powerful flavan-3-ol antioxidant, (+)-catechin, were isolated from the edible fruits of Harpephyllum caffrum while a mixture of cardanols, an alkyl p-coumaric acid ester, and (+)-catechin were isolated from the stem bark. This is the first report of these compounds being isolated from this plant. The antioxidant capacity of (+)-catechin was higher than the other isolated compounds as well as the known antioxidant, ascorbic acid. PMID:25310809

  19. Flavanol monomer-induced changes to the human faecal microflora

    OpenAIRE

    Tzounis, Xenofon; Vulevic, Jelena; Kuhnle, Gunter; George, Trevor; Leonczak, Jadwiga; Gibson, Glenn; Kwik-Uribe, Catherine; Spencer, Jeremy

    2008-01-01

    We have investigated the bacterial-dependent metabolism of ( − )-epicatechin and (+)-catechin using a pH-controlled, stirred, batch-culture fermentation system reflective of the distal region of the human large intestine. Incubation of ( − )-epicatechin or (+)-catechin (150 mg/l or 1000 mg/l) with faecal bacteria, led to the generation of 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone, 5-phenyl-γ-valerolactone and phenylpropionic acid. However, the formation of these metabolites from (+)-catechin ...

  20. Quantitation of flavanols, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and benzoic Acid derivatives after identification by LC-MS

    Science.gov (United States)

    A general method was developed for the systematic quantitation of catechins, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and hydroxybenzoic acid derivatives (mainly hydrolyzable tannins) using the UV relative mole response factors (MRRF) of the reference standard from ea...

  1. Antioxidant Activity of Phenolic Compounds in Bulk Camellia Oil and Corresponding Oil in Water (O/W Emulsions

    Directory of Open Access Journals (Sweden)

    Yong Zhu

    2013-09-01

    Full Text Available The antioxidant activities of gallic acid, propyl gallate, (+-catechin and quercetin in bulk camellia oil and corresponding emulsions were investigated using hydroperoxides and nonanal as indicators of oxidation. In bulk oil, these phenolic compounds showed antioxidant activities with the order of gallic acid>quercetin>propyl gallate> (+-catechin when measured using hydroperoxides and gallic acid>quercetin>(+-catechin>propyl gallate using nonanal. In emulsions, propyl gallate and (+-catechin showed antioxidant activities for the entire duration of the experiment, while quercetin and gallic acid displayed antioxidant activities for 10 days, and then pro-oxidant activities thereafter. Results suggested that in bulk oil, the antioxidant activity was regulated by phenol polarity and hydrogen atom donating ability too. In emulsions, the antioxidant activity of phenolic compounds seems to be related to their affinity toward the emulsifing agent rather than their polarity.

  2. Green tea as a source of food antioxidants

    DEFF Research Database (Denmark)

    Yin, Jie

    Safe” (GRAS-status). In this PhD project, green tea rich in polyphenol compounds catechins was selected as the natural source of antioxidants. The aim of the project was to investigate green tea as a source of natural antioxidants for use in processed foods. First of all, the antioxidant effects of...... green tea catechins and green tea extract were investigated in terms of scavenging efficiency of the food-derived free radicals. The relevant experimental methods were based on electrochemical detection of oxygen consumption, electron spin resonance (ESR) spectroscopy, Rancimat test and liposome...... oxidation test. In addition, antioxidant interactions for individual green tea catechins or green tea extract in combination with endogenous antioxidant, α-tocopherol, were studied. The results showed that green tea catechins possess excellent antioxidant activity against the oxidative damage of lipids...

  3. Proanthocyanidin A2 purification and levels found in American cranberry (Vaccinium macrocarpon Ait.) products

    Science.gov (United States)

    In this study, five common proanthocyanidin purification techniques were evaluated prior to phloroglucinolysis, followed by HPLC analysis. An optimized purification method was then used to identify and quantify the proanthocyanidins (extension and terminal units of epigallocatechin, catechin, epicat...

  4. Altering the phenolics profile of a green tea leaves extract using exogenous oxidases.

    Science.gov (United States)

    Verloop, Annewieke J W; Gruppen, Harry; Bisschop, Robbin; Vincken, Jean-Paul

    2016-04-01

    Transformation from green tea leaves into black tea involves oxidation of catechins into theaflavins and other complex phenolics by endogenous enzymes in tea leaves. By employing tyrosinase and laccase, both from Agaricus bisporus, on green tea catechins, the oxidation process was directed towards a higher theaflavins content, which is considered an important quality parameter in tea. The main tea catechins were incubated with tyrosinase and laccase, and product formation was monitored by RP-UHPLC-PDA-ESI-MS. The kind of catechin, their substitution with a galloyl group, and the type of oxidase used were important factors determining theaflavin concentrations. In particular, incubation of epicatechin with epigallocatechin with tyrosinase gave a high, stable theaflavin content. In a green tea extract, tyrosinase increased the proportion of theaflavins by twofold compared to black tea. Laccase mainly formed insoluble complexes. Our results indicate that the phenolic profile of tea can be modulated by using commercially available exogenous oxidases. PMID:26593607

  5. Beneficial effects of green tea: A literature review

    Directory of Open Access Journals (Sweden)

    Kuttan Ramadasan

    2010-04-01

    Full Text Available Abstract The health benefits of green tea for a wide variety of ailments, including different types of cancer, heart disease, and liver disease, were reported. Many of these beneficial effects of green tea are related to its catechin, particularly (--epigallocatechin-3-gallate, content. There is evidence from in vitro and animal studies on the underlying mechanisms of green tea catechins and their biological actions. There are also human studies on using green tea catechins to treat metabolic syndrome, such as obesity, type II diabetes, and cardiovascular risk factors. Long-term consumption of tea catechins could be beneficial against high-fat diet-induced obesity and type II diabetes and could reduce the risk of coronary disease. Further research that conforms to international standards should be performed to monitor the pharmacological and clinical effects of green tea and to elucidate its mechanisms of action.

  6. Antioxidant effects of green tea polyphenols

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The unprecedented interest in the antioxidant activity of green tea polyphenols (GTP) is due to the apparent health benefits of tea drinking and the experimental results with the polyphenols. The results suggest that the galloylated catechins show stronger antioxidant effect than that of nongalloylated catechins and the double bond in C ring also plays an important role in this effect. There are synergic effects between different catechins and the antioxidant effectof (+)-epimers is stronger than that of (-)-epimers. The active site to scavenge free radicals mainly locates in p-hydroxyl of phenol in gallic acid and hydroxyl of phenol in the pyrane also shows activity. The large π bond in chromane and benzene ring of catechin is the structure base for their antioxidant effects. The prevent effect of GTP against diseases and their redox regulation in cell signal pathway are very important to be studied in the future.

  7. Comparative Evaluation of Different Co-Antioxidants on the Photochemical- and Functional-Stability of Epigallocatechin-3-gallate in Topical Creams Exposed to Simulated Sunlight

    OpenAIRE

    Scalia, Santo; Marchetti, Nicola; Bianchi, Anna

    2013-01-01

    The catechin (−)-epigallocatechin-3-gallate (EGCG) exhibits high antioxidant activity and it has been reported to provide protection of the skin against damage induced by solar UV radiation. However, EGCG is highly unstable under sunlight. The present study aimed to compare the effectiveness of the co-antioxidant agents vitamin E, butylated hydroxytoluene, vitamin C and a-lipoic acid for their potential to protect the catechin from photochemical degradation. Model creams (oil-in-water emulsio...

  8. Phenolic and Theobromine Contents of Commercial Dark, Milk and White Chocolates on the Malaysian Market

    OpenAIRE

    Cheng Chia Meng; Abbe Maleyki Mhd Jalil; Amin Ismail

    2009-01-01

    Chocolate contains a wide range of antioxidants that includes soluble phenolic compounds (phenolic acids, catechin, epicatechin, and proanthocyanidins), insoluble polymeric phenolics and methylxanthines. The objective of this study was to determine phenolic and theobromine contents in dark (DC), milk (MC), and white (WC) chocolates commonly found in the Malaysian marketplace. Total phenolic and flavonoids were determined by means of a spectrometric assay, while catechin, epicatechin and theob...

  9. New insights into the mechanisms of polyphenols beyond antioxidant properties; lessons from the green tea polyphenol, epigallocatechin 3-gallate

    OpenAIRE

    Hae-Suk Kim; Quon, Michael J.; Jeong-a Kim

    2014-01-01

    Green tea is rich in polyphenol flavonoids including catechins. Epigallocatechin 3-gallate (EGCG) is the most abundant and potent green tea catechin. EGCG has been extensively studied for its beneficial health effects as a nutriceutical agent. Based upon its chemical structure, EGCG is often classified as an antioxidant. However, treatment of cells with EGCG results in production of hydrogen peroxide and hydroxyl radicals in the presence of Fe (III). Thus, EGCG functions as a pro-oxidant in s...

  10. Isolation and Identification of the Phenolic Compounds from the Roots of Sanguisorba officinalis L. and Their Antioxidant Activities

    OpenAIRE

    Zhe Wang; Lu He; Zi-Long Zhang; Xin Liu; Shuang Zhang; Guang-Shu Wang

    2012-01-01

    Four phenolic compounds were isolated from the roots of Sanguisorba officinalis L. by silica gel column chromatography and preparative HPLC. On the basis of chemical and spectroscopic methods, their structures were identified as methyl 4-O-β-D-glucopyranosy-5-hydroxy-3-methoxylbenzoate (1), 3,3′,4′-tri-O-methylellagic acid (2), fisetinidol-(4α-8)-catechin (3), and (+)-catechin (4). Compound 1 is a new phenolic glycoside and compounds 2 and 3 were isolated...

  11. Polyphenols profile and antioxidant activity of skin and pulp of a rare apple from Marche region (Italy)

    OpenAIRE

    Giomaro, Giovanna; Karioti, Anastasia; Bilia, Anna Rita; Bucchini, Anahi; Giamperi, Laura; Ricci, Donata; Fraternale, Daniele

    2014-01-01

    Background Apples are an important source of polyphenols in the human diet and the consumption of this fruit has been linked to the prevention of degenerative diseases. Results Catechins, procyanidins, hydroxycinnamic acids, flavonol glycosides, dihydrochalcone glycosides and one anthocyanin: cyanidin-3-O-galactoside, were identified both in the peel and pulp. Procyanidins, catechins and flavonols represent the main constituents of peel. Concerning the antioxidant activity, in the reduction o...

  12. Comparative Evaluation of Different Co-Antioxidants on the Photochemical- and Functional-Stability of Epigallocatechin-3-gallate in Topical Creams Exposed to Simulated Sunlight

    OpenAIRE

    Santo Scalia; Nicola Marchetti; Anna Bianchi

    2013-01-01

    The catechin (−)-epigallocatechin-3-gallate (EGCG) exhibits high antioxidant activity and it has been reported to provide protection of the skin against damage induced by solar UV radiation. However, EGCG is highly unstable under sunlight. The present study aimed to compare the effectiveness of the co-antioxidant agents vitamin E, butylated hydroxytoluene, vitamin C and a-lipoic acid for their potential to protect the catechin from photochemical degradation. Model creams (oil-in-wat...

  13. TLC analysis of some phenolic compounds in kombucha beverage

    OpenAIRE

    Malbaša Radomir V.; Lončar Eva S.; Kolarov Ljiljana A.

    2004-01-01

    Black and green tea contains a wide range of natural phenolic compounds Flavanoids and their glycosides, catechins and the products of their condensation, and phenolic acids are the most important. Kombucha beverage is obtained by fermentation of tea fungus on black or green tea sweetened with sucrose. The aim of this paper was to investigate the composition of some phenolic compounds, catechin, epicatechin, quercetin, myricetin, gallic and tanic acid, and monitoring of their status during te...

  14. Green Tea as Inhibitor of the Intestinal Absorption of Lipids: Potential Mechanism for its Lipid-Lowering Effect1

    OpenAIRE

    Koo, Sung I.; Noh, Sang K.

    2007-01-01

    Animal and epidemiological studies suggest that green tea catechins may reduce the risk of cardiovascular diseases (CHD). The health benefit of green tea has been attributed to its antioxidant and anti-inflammatory properties; however, considerable evidence suggests that green tea and its catechins may reduce the risk of CHD by lowering the plasma levels of cholesterol and triglyceride. Although the mechanism underlying such effect of green tea is yet to be determined, it is evident from in v...

  15. Die Wirkung von grünem Tee, schwarzem Tee sowie schwarzem Tee mit Milch auf die vaskuläre Endothelfunktion bei postmenopausalen Frauen

    OpenAIRE

    Portatius, Amélie von

    2010-01-01

    Experimental and clinical studies indicate that tea exerts protection against cardiovascular diseases. It is assumed that catechins are the tea components responsible for these beneficial effects. In black tea, catechin concentrations are significantly lower than in green tea. However, a question of much debate is whether addition of milk modifies the biological activities of tea. A total of 21 healthy female volunteers consumed either 500 mL of freshly brewed green tea, black tea, black tea ...

  16. Antioxidant activities of Crataegus monogyna extracts.

    Science.gov (United States)

    Bahorun, T; Trotin, F; Pommery, J; Vasseur, J; Pinkas, M

    1994-08-01

    Interesting antioxidant activities of extracts from different vegetative and reproductive organs of Crataegus monogyna harvested at different stages of growth have been determined by the malondialdehyde-thiobarbituric acid (MDA) test on hepatic microsomal preparations and compared to the contents in total phenolics, proanthocyanidins, catechins, flavonoids, and phenolic acids. The best correlations were established with total phenols while activities in leaves seem to be influenced by flavonoids and in flowers and fruits by proanthocyanidins and catechins. PMID:7938266

  17. Polyphenols as inhibitors of carcinogenesis.

    OpenAIRE

    Yang, C S; Lee, M. J.; Chen, L.; Yang, G.Y.

    1997-01-01

    Many polyphenolic compounds have demonstrated anticarcinogenic activities in animal models. These compounds include flavanone, flavonols, isoflavone, and catechins. In this article, tea catechins will be used as an example to illustrate current research in this area. Many laboratory studies have demonstrated the inhibition of tumorigenesis in animal models by different tea preparations. The animal models include tumorigenesis in the mouse lung, rat and mouse esophagi, mouse forestomach, mouse...

  18. COMPARISON OF THE COMPOSITION AND ANTIOXIDANT CAPACITIES OF GREEN TEAS PRODUCED FROM THE ASSAM AND THE CHINESE VARIETIES CULTIVATED IN THAILAND

    Directory of Open Access Journals (Sweden)

    Theerapong Theppakorn

    2014-04-01

    Full Text Available Tea (Camellia sinensis L. has attracted much attention due to the antioxidant capacities of bioactive compounds present in it, which are considered beneficial to consumer health. In Thailand, commercially cultivated teas are the Assam and the Chinese cultivars which both are processed as green teas. The aim of this study was to investigate the chemical composition and antioxidant capacities of these teas. Samples were collected from tea factories and analyzed for caffeine content (CF, total polyphenol content (TPC, total catechin content (TCC, (--gallocatechin (GC, (--epigallocatechin (EGC, (+-catechin (C, (--epicatechin (EC, (--epigallocatechin gallate (EGCG, (--gallocatechin gallate (GCG, (--epicatechin gallate (ECG, (--catechin gallate (CG, the 2,2-diphenyl-1-picrylhydrazyl (DPPH radical-scavenging activity (DPPH-assay and the ferric reducing antioxidant power (FRAP-assay. The results showed that green tea produced from the Assam cultivar was significantly higher in CF and TPC than the Chinese cultivar. There was no significant difference in the TCC. Both cultivars had the same level of radical scavenging capacity (DPPH. As opposed to the radical scavenging capacity, there was a significant difference in the reducing power capacity (FRAP. The FRAP of the Assam was significantly higher than that of the Chinese tea. There was a significant difference in the individual catechins; the Assam cultivar mainly contained ECG, EGCG, and EC, whereas the major catechins in the Chinese cultivar were EGCG and EGC. Results from this study suggest that the profiles of catechins in green teas manufactured in Thailand might contribute to the cultivars.

  19. Auto-oxidation products of epigallocatechin gallate activate TRPA1 and TRPV1 in sensory neurons.

    Science.gov (United States)

    Kurogi, Mako; Kawai, Yasushi; Nagatomo, Katsuhiro; Tateyama, Michihiro; Kubo, Yoshihiro; Saitoh, Osamu

    2015-01-01

    The sensation of astringency is elicited by catechins and their polymers in wine and tea. It has been considered that catechins in green tea are unstable and auto-oxidized to induce more astringent taste. Here, we examined how mammalian transient receptor potential V1 (TRPV1) and TRPA1, which are nociceptive sensors, are activated by green tea catechins during the auto-oxidation process. Neither TRPV1 nor TRPA1 could be activated by any of the freshly prepared catechin. When one of the major catechin, epigallocatechin gallate (EGCG), was preincubated for 3h in Hank's balanced salt solution, it significantly activated both TRP channels expressed in HEK293 cells. Even after incubation, other catechins showed much less effects. Results suggest that only oxidative products of EGCG activate both TRPV1 and TRPA1. Dorsal root ganglion (DRG) sensory neurons were also activated by the incubated EGCG through TRPV1 and TRPA1 channels. Liquid chromatography-mass spectrometry revealed that theasinensins A and D are formed during incubation of EGCG. We found that purified theasinensin A activates both TRPV1 and TRPA1, and that it stimulates DRG neurons through TRPV1 and TRPA1 channels. Results suggested a possibility that TRPV1 and TRPA1 channels are involved in the sense of astringent taste of green tea. PMID:25422365

  20. Assessment of the effect of type of dairy product and of chocolate matrix on the oral absorption of monomeric chocolate flavanols in a small animal model.

    Science.gov (United States)

    Gossai, D; Lau-Cam, C A

    2009-03-01

    This study has examined the effects of type of dairy product (whole milk, skim milk, heavy cream) and chocolate matrix (baking, dark, dairy milk, white) on the oral absorption of the chocolate flavanols (+)-catechin and (-)-epicatechin in a small animal model. In the study, each flavanol compound, as a solution in water or a dairy product or as a chocolate dispersion in water, was administered intragastrically to male Sprague-Dawley rats in an amount equal to or equivalent to 350 mg/kg. In each instance, blood samples were collected over a 5 h period, and used to measure plasma total catechin concentrations by HPLC after enzymatic hydrolysis of flavanol conjugates. Pharmacokinetic data were evaluated using a one compartment approach. Whole milk and heavy cream, and to a much lesser extent skim milk, lowered the oral absorption of both (+)-catechin and (-)-epicatechin and altered the AUC, C(max), k(a), k(e) and t1/2 values in direct proportion to their fat, but not to their protein, content. In addition, the t(max) for solutions of (-)-epicatechin in water and skim milk occurred 2 h earlier than from solutions in whole milk and heavy cream. Similarly, dispersions of baking chocolate in water and in whole milk yielded plasma levels of monomeric catechins that were, respectively, about equal to and much lower than those from aqueous solutions of authentic flavanols. A determining role for a chocolate matrix (dark, dairy milk or white chocolate) on the oral absorption of its constitutive monomeric flavanols was suggested by the apparent variability in plasma total catechins levels that existed among them both before and after their spiking with equal amounts of exogenous (+)-catechin and (-)-epicatechin. Such a variability could reflect differences among different chocolates in terms of their physical properties, matrix components, and matrix characteristics imposed by the manufacturing process used for each type of chocolate. In all the experiments, (+)-catechin

  1. Antioxidant activities and radical scavenging activities of flavonoids studied by the electrochemical methods and ESR technique based on the novel paramagnetic properties of poly(aniline-co-5-aminosalicylic acid)

    International Nuclear Information System (INIS)

    Graphical abstract: ESR spectra of the PAASA/RGO/graphite electrodes: (1) in the buffer solution consisting of 0.20 M phosphate and methanol (80: 20, v/v), (2) in the buffer solutions containing 150 μM of (+)-catechin. -- Abstract: Four kinds of flavonoid, viz. flavanone naringenin, Flavone apigenin, flavonol kaempferol, and flavanol (+)-catechin, are used to investigate their antioxidant and radical scavenging activitis in the water-methanol solution of pH 6.3, using the electrochemical methods and electron spin resonance (ESR) technique. Poly(aniline-co-5-aminosalicylic acid) (PAASA) is first used as a radical source that was polymerized on a reduced graphene oxide (RGO)/glassy carbon (GC) disk or on the RGO/graphite fiber electrode. The assessment of the antioxidant activities is performed using both cyclic voltammetry and the open circuit potential measurement. On the basis of results from both electrochemical mathods, the order of the antioxidant actitvities of flavonoids is as follows: (+)-catechin > kaempferol > apigenin > naringenin However, the difference in the antioxidant activities between naringenin and apigenin is very small. On the basis of the ESR signal intensities of PAASA, the order of the radical scavenging activities of flavonoids is in good agreement with that of the above antioxdant activities.Three oxidation peaks on the cyclic voltammograms of (+)-catechin are first detected, which gives us a deep insight into the oxidation mechanism of (+)-catechin

  2. Assessment of the antioxidant potential of natural food and plant extracts in fresh and previously frozen pork patties.

    Science.gov (United States)

    Mc Carthy, T L; Kerry, J P; Kerry, J F; Lynch, P B; Buckley, D J

    2001-02-01

    Antioxidant activities of aloe vera, fenugreek, ginseng, mustard, rosemary, sage, soya protein, tea catechins and whey protein concentrate (35% protein) were evaluated in pork patties prepared from both fresh and previously frozen (-20°C) pork. Chemical analysis showed test ingredients to be more effective in reducing lipid oxidation in patties made from previously frozen pork. Tea catechins, rosemary and sage were identified as being the most effective antioxidants with potency decreasing in the following order: tea catechins>rosemary>sage. Optimum addition rates of these ingredients suggested levels of 0.25, 0.10, 0.05% for tea catechins, rosemary and sage, respectively. Soya protein (0.10%) increased meat redness in fresh pork patties producing significantly (P0.05) differences in Hunter 'L' and 'b' values were found between test and control samples on storage. The pH values of tea catechins, sage and soya protein fluctuated over time. Fresh pork patties with mustard and ginseng caused an initial decrease followed by a subsequent increase in pH values. Fenugreek caused an initial increase in pH values followed by a decrease from day 3 onwards. PMID:22061361

  3. Procyanidins (Condensed Tannins) in Green Cell Suspension Cultures of Douglas Fir Compared with Those in Strawberry and Avocado Leaves by Means of C(18)-Reversed-phase Chromatography.

    Science.gov (United States)

    Stafford, H A; Lester, H H

    1980-12-01

    The procyanidins (the most common type of proanthocyanidin or condensed tannin) from cell suspension cultures derived from cotyledons of Douglas Fir have been compared with those isolated from leaves of strawberry and avocado. Seventy per cent methanol (v/v) extracts from 100 milligrams fresh weight samples were analyzed by a combination of C(18)-reversed-phase columns with high-performance liquid chromatography, and normal phase paper chromatography. (-)-Epicatechin and its oligomers were generally retarded longer on C(18) columns than the corresponding units made of (+)-catechin when eluted with solvents made up of 5% acetic acid alone or mixed with methanol up to 15% (v/v). Douglas fir preparations contained the most complex set of procyanidins and consisted of oligomers of catechin and epicatechin, whereas strawberry and avocado contained mainly (+)-catechin and (-)-epicatechin derivatives, respectively. PMID:16661581

  4. Assessment of flavanol stereoisomers and caffeine and theobromine content in commercial chocolates.

    Science.gov (United States)

    Alañón, M E; Castle, S M; Siswanto, P J; Cifuentes-Gómez, T; Spencer, J P E

    2016-10-01

    Assessment of the flavanol composition of 41 commercial chocolates was by HPLC-DAD. Among individual flavonols ranged from 0.095 to 3.264mgg(-1), epicatechin was the predominant flavanol accounting for 32.9%. Contrary to catechin, epicatechin was a reliable predictive value of the polyphenol content. Conversely the percentage of theobromine used as a proxy measure for nonfat cocoa solids (NFCS) was not a good predictor of epicatechin or flavanol content. In a further chiral analysis, the naturally occurring forms of cocoa flavanols, (-)-epicatechin and (+)-catechin, was determined joint the occurrence of (+)-epicatechin and (-)-catechin due to the epimerization reactions produced in chocolate manufacture. (-)-Epicatechin, the most bioactive compound and predominant form accounted of 93%. However, no positive correlation was found with% cocoa solids, the most significant quality parameter. PMID:27132838

  5. Green tea flavour determinants and their changes over manufacturing processes.

    Science.gov (United States)

    Han, Zhuo-Xiao; Rana, Mohammad M; Liu, Guo-Feng; Gao, Ming-Jun; Li, Da-Xiang; Wu, Fu-Guang; Li, Xin-Bao; Wan, Xiao-Chun; Wei, Shu

    2016-12-01

    Flavour determinants in tea infusions and their changes during manufacturing processes were studied using Camellia sinensis cultivars 'Bai-Sang Cha' ('BAS') possessing significant floral scents and 'Fuding-Dabai Cha' ('FUD') with common green tea odour. Metabolite profiling based on odour activity threshold revealed that 'BAS' contained higher levels of the active odorants β-ionone, linalool and its two oxides, geraniol, epoxylinalool, decanal and taste determinant catechins than 'FUD' (pmanufacturing processes, the levels of linalool and geraniol decreased whereas those of β-ionone, linalool oxides, indole and cis-jasmone increased. Compared with pan-fire treatment, steam treatment reduced the levels of catechins and proportion of geraniol, linalool and its derivatives, consequently, reducing catechin-related astringency and monoterpenol-related floral scent. Our study suggests that flavour determinant targeted modulation could be made through genotype and manufacturing improvements. PMID:27374591

  6. Phenolic compounds in cultures of tissues of tea plants and the effect of light on their synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Koretskaya, T.F.; Zaprometov, M.N.

    1975-01-01

    Stem and leaf calluses of tea plants (Camellia sinensis) retain the capacity for synthesis of phenolic compounds. The content of phenolic compounds comprises 2 to 5 percent of dry weight, the main share (80 to 95 percent) belonging to catechins and leucoanthocyans, including their polymeric forms. The following compounds were detected in callus tissue: (--)-epicatechin, (+)-catechin, two leucoanthocyans, and several unidentified phenolic compounds that fluoresce in UV. (--)-Epicatechin is predominant. In contrast to tissues of an intact plant, the callus does not contain gallocatechins or free gallic acid under the given cultivation conditions. The content of phenolic compounds changes in proportion to callus growth, their greatest amount being formed during the phase of intensive growth. Light stimulates synthesis of phenolic compounds, including the most reduced group of flavonoids, viz., leucoanthocyans and catechins.

  7. Chemical constituents of the stem bark of Vochysia thyrsoidea Pohl. (Vochysiaceae) and evaluation of their cytotoxicity and inhibitory activity against cathepsins B and K; Constituintes quimicos das cascas do caule de Vochysia thyrsoidea Pohl. (Vochysiaceae) e avaliacao das atividades citotoxica e inibitoria frente as catepsinas B e K

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Lorena Ramos Freitas de; Silva, Jame' s A. da; Vieira, Paulo Cezar [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil). Departamento de Quimica; Costa, Maisa Borges; Santos, Mirley Luciene dos; Menezes, Antonio Carlos Severo, E-mail: amenezes@ueg.br [Universidade Estadual de Goias (UEG), Anapolis, GO (Brazil). Unidade Universitaria de Ciencias Exatas e Tecnologicas; Sbardelotto, Aline Borba; Pessoa, Claudia do O; Moraes, Manoel Odorico de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Fac. de Medicina. Dept. de Fisiologia e Farmacologia

    2014-04-15

    A new flavonoid, catechin-3-O-(3{sup -}O-trans-cinnamoyl)-α-rhamnopyranoside, along with known compounds, catechin-3-O-α-rhamnopyranoside, 3-oxo-urs-12-en-28-oic acid, 2,4,6-trimethoxybenzoic acid, 2-butyl-D-fructofuranoside and 1-butyl-D-fructofuranoside, has been isolated from the stem bark of V. thyrsoidea. These compounds were assayed for inhibition of protease activity (cathepsins B and K) and against cancer cell lines. Catechin-3-O-(3{sup -}O-trans-cinnamoyl)-α-rhamnopyranoside showed moderate inhibitory activity (IC{sub 50} = 62.02 µM) against cathepsin B while 2-butyl-D-fructofuranoside was the most potent against a strain of CNS (SF-295) and human leukemia (HL-60) with IC{sub 50} = 36.80 μM and IC{sub 50} = 25.37 μM, respectively (author)

  8. Constituintes químicos das folhas de Riedeliella graciliflora Harms (Leguminosae

    Directory of Open Access Journals (Sweden)

    Mayker Lazaro Dantas Miranda

    2012-01-01

    Full Text Available A new salicylic acid derivative, pentacosanyl salicylate, was isolated from the leaves of the plant toxic to cattle, Riedeliella graciliflora, in addition to a digalactosyldiacylglycerol (DGDG, 1,2-di-O-α-linolenoyl-3-O-α-D-galactopyranosyl-(1→6-β-D-galactopyranosyl-glycerol, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-α-L-rhamnopyranoside, quercetin-3-O-α-L-rhamnopyranoside, rutin, (+-catechin and the dimer (+-catechin-(4β-8-catechin, glutinol, squalene, β-sitosterol, stigmasterol, phytol, β-carotene, α-tocopherol and ficaprenol-12. Their structures were determined using spectral techniques (MS, IR, and NMR-1D and 2D and based on literature data.

  9. Chiral cyclodextrin-modified micellar electrokinetic chromatography and chemometric techniques for green tea samples origin discrimination.

    Science.gov (United States)

    Pasquini, Benedetta; Orlandini, Serena; Goodarzi, Mohammad; Caprini, Claudia; Gotti, Roberto; Furlanetto, Sandra

    2016-04-01

    Catechins and methylxanthines were determined in 92 green tea (GT) samples originating from Japan and China by using micellar electrokinetic chromatography with the addition of (2-hydroxypropyl)-β-cyclodextrin. GT samples showed high concentrations of (-)-epigallocatechin gallate and caffeine, with (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epicatechin in relevant content and (+)-catechin, (-)-catechin and theobromine in much lower amounts. The amount of all the considered compounds was higher for Chinese GTs, with the exception of (-)-epicatechin gallate. Pattern recognition methods were applied to discriminate GTs according to geographical origin, which is an important factor to determine quality and reputation of a commercial tea product. Data analysis was performed by principal component analysis and hierarchical cluster analysis as exploratory techniques. Linear discriminant analysis and quadratic discriminant analysis were utilized as discrimination techniques, obtaining a very good rate of correct classification and prediction. PMID:26838375

  10. Chemical constituents of leaves from Riedeliella graciliflora Harms (Leguminosae); Constituintes quimicos das folhas de Riedeliella graciliflora Harms (Leguminosae)

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Mayker Lazaro Dantas; Souza, Alex Fonseca; Rodrigues, Edilene Delphino; Garcez, Fernanda Rodrigues; Garcez, Walmir Silva, E-mail: walmir.garcez@ufms.br [Universidade Federal de Mato Grosso do Sul, Campo Grande, MS (Brazil). Dept. de Quimica; Abot, Alfredo [Universidade Estadual de Mato Grosso do Sul (UEMGS), Aquidauana, MS (Brazil). Unidade Universitaria de Aquidauana

    2012-07-01

    A new salicylic acid derivative, pentacosanyl salicylate, was isolated from the leaves of the plant toxic to cattle, Riedeliella graciliflora, in addition to a digalactosyldiacylglycerol (DGDG), 1,2-di-O-{alpha}-linolenoy1-3-O-{alpha}-D-galactopyranosy1 -(1{yields}6)-{beta}-D-galactopyranosyl-glycerol, kaempferol-3-O-{beta}-D-glucopyranoside, kaempferol-3-O-{alpha}-L-rhamnopyranoside, quercetin-3-O-{alpha}-L-rhamnopyranoside, rutin, (+)-catechin and the dimer (+)-catechin-(4{beta}-8)-catechin, glutinol, squalene, {beta}-sitosterol, stigmasterol, phytol, {beta}-carotene, a-tocopherol and ficaprenol-12. Their structures were determined using spectral techniques (MS, IR, and NMR-1D and 2D) and based on literature data. (author)

  11. Chemical constituents from Swietenia macrophylla bark and their antioxidant activity.

    Science.gov (United States)

    Falah, S; Suzuki, T; Katayama, T

    2008-08-15

    Chemical constituents of the bark of Swietenia macrophylla King (Meliaceae) was investigated not only to develop further bark utilization but also to understand the biochemical function of the bark in the forest environment. A new phenylpropanoid-substituted catechin, namely, swietemacrophyllanin [(2R*,3S*,7"R*)-catechin-8,7"-7,2"-epoxy-(methyl 4",5"-dihydroxyphenylpropanoate)] (1) was isolated from the bark of S. macrophylla together with two known compounds, catechin (2) and epicatechin (3). The structure of 1 was elucidated by spectroscopic data and by comparison of the NMR data with those of catiguanins A and B, phenylpropanoid-substituted epicatechins. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the isolated compounds indicated that all of the three compounds have strong activity compared with trolox as a reference. Swietemacrophyllanin (1) had the strongest activity with a 50% inhibitory concentration (IC50) value of 56 microg mL(-1). PMID:19266907

  12. Impact of a pectic polysaccharide on oenin copigmentation mechanism.

    Science.gov (United States)

    Fernandes, Ana; Brás, Natércia F; Oliveira, Joana; Mateus, Nuno; de Freitas, Victor

    2016-10-15

    Copigmentation plays an important role in the colors provided by anthocyanins. However, little attention has been paid to the interaction between anthocyanins and cell wall compounds (e.g. polysaccharides) and the impact of this interaction on anthocyanins color, a fundamental issue to be considered in industrial applications of these pigments as food colorants. The copigmentation binding constants (KCP) for the interaction between malvidin-3-O-glucoside and (+)-catechin in the presence of low methoxylated pectic polysaccharide were determined. The values obtained showed that in the presence of pectic polysaccharide the copigmentation binding constants decreased. These results probably suggest the occurrence of competition equilibrium in which the presence of pectin limited the association between catechin and oenin. (1)H NMR studies revealed that the dissociation constant determined for these complexes was very similar in absence and presence of 1.5g/L pectin with this polysaccharide apparently not affecting the strength of anthocyanin-catechin binding. PMID:27173529

  13. Cocoa Extract Indicated Has Activity on Selectively Killing Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ariza Budi Tunjung Sari

    2015-09-01

    Full Text Available Effect of the cocoa crude extract on mortality of breast cancer cell lines i.e. MCF-7, T47D and normal cell (Vero, was observed. Crude cocoa extract prepared from a freshly dried cocoa bean that was containing 14% catechin and 0.6% caffeine. Catechin and caffeine content were modulated to 2-folds (28% catechin or 1.2% caffeine and 3-folds (42% catechin or 1.8% caffeine by adding pure compounds. Extracts were dissolved in dimethylsulfoxide (DMSO at concentrations ranging from 200 to 1600 μg/ml. The positive control was doxorubicin (0.5-16 μg/ml in DMSO. Cell lines (MCF-7, T47D, and Vero were incubated in test sample for 24h at 37°, prior to 3-(4,4-dimetylthiazole-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. The absorbance of each well was measured at 550 nm, and lethal concentration (LC50 was calculated. The cocoa extract induced mortality of breast cancer cell lines but not in Vero cells. The effect on MCF-7 was greater than on T47D, given the LC50 was 1236 μg/ml (MCF-7 and 1893 μg/ml (T47D. Cytotoxic potential of cocoa extract was much lower than doxorubicin whose LC50 was 0,777 μg/ml (MCF-7 and 0,082 μg/ml (T47D. Increasing catechin content to 2-folds did not significantly affect LC50 value, but 3-folds catechin content reduced LC50 to 1021 μg/ml. Meanwhile increasing caffeine content to 2-folds significantly reduced LC50 to 750 μg/ml, however, 3-fold content resulted in slightly higher LC50 at 780 μg/ml. This indicates that cocoa extract have anti-cancer potential, and purification may improve this property.

  14. Procyanidin xylosides from the bark of Betula pendula.

    Science.gov (United States)

    Liimatainen, Jaana; Karonen, Maarit; Sinkkonen, Jari

    2012-04-01

    A procyanidin dimer xyloside, catechin-(4α→8)-7-O-β-xylopyranosyl-catechin, was isolated from the inner bark of Betula pendula and its structure was determined using 1D and 2D NMR, CD and high-resolution ESIMS. Interestingly, the 7-O-β-xylopyranose unit was found to be present in the lower terminal unit of the dimer. In addition to this procyanidin dimer xyloside, an entire series of oligomeric and polymeric procyanidin xylosides was detected. Their structures were investigated by hydrophilic interaction HPLC-HRESIMS. Procyanidin glycosides are still rarely found in nature. PMID:22273040

  15. Triterpenes, Phenols, and Other Constituents from the leaves of Ochroma pyramidale(Balsa Wood, Bombacaceae). Preferred Conformations of 8-C-b-D-Glucopyranosyl-apigenin (vitexin)

    OpenAIRE

    Erika Vázquez; Esteban M. Martínez; Juan Antonio Cogordán; Guillermo Delgado

    2002-01-01

    Lupeol, oleanolic acid, stigmasterol, b-sitosterol, b- sitosteryl-b-D-glucopyranoside, catechin, epi-catechin, and 8-C-b-Dglucopyranosylapigenin (vitexin) were isolated from the acetonic extract of the leaves of Ochroma pyramidale(balsa wood, Bombacaceae), a tree noted by its exceedingly light wood. 1H and 13C NMR of 8-C-b-D-glucopyranosyl-apigenin (vitexin) at room temperature exhibited doubling of some signals, suggesting the presence of atropisomers. 1H NMR spectra at 70 °C showed one set ...

  16. Effects of (−)-Gallocatechin-3-Gallate on Tetrodotoxin-Resistant Voltage-Gated Sodium Channels in Rat Dorsal Root Ganglion Neurons

    OpenAIRE

    Jian-Min Jiang; Pei-Qing Liu; Jin-Lei Guo; Yan-Yan Jia; Yan Zhang

    2013-01-01

    The (−)-gallocatechin-3-gallate (GCG) concentration in some tea beverages can account for as much as 50% of the total catechins. It has been shown that catechins have analgesic properties. Voltage-gated sodium channels (Nav) mediate neuronal action potentials. Tetrodotoxin inhibits all Nav isoforms, but Nav1.8 and Nav1.9 are relatively tetrodotoxin-resistant compared to other isoforms and functionally linked to nociception. In this study, the effects of GCG on tetrodotoxin-resistant Na+ curre...

  17. Electrochemical and theoretical complexation studies for Zn and Cu with individual polyphenols

    Energy Technology Data Exchange (ETDEWEB)

    Esparza, I. [Departamento de Quimica y Edafologia, Universidad de Navarra, c/ Irunlarrea s/n, 31080 Pamplona, Navarra (Spain); Salinas, I. [Departamento de Quimica y Edafologia, Universidad de Navarra, c/ Irunlarrea s/n, 31080 Pamplona, Navarra (Spain); Santamaria, C. [Departamento de Quimica y Edafologia, Universidad de Navarra, c/ Irunlarrea s/n, 31080 Pamplona, Navarra (Spain); Garcia-Mina, J.M. [INABONOS, Poligono Arazuri, 31160 Orcoyen, Navarra (Spain); Fernandez, J.M. [Departamento de Quimica y Edafologia, Universidad de Navarra, c/ Irunlarrea s/n, 31080 Pamplona, Navarra (Spain)]. E-mail: jmfdez@unav.es

    2005-07-06

    Zn and Cu interactions with three selected flavonoids (catechin, quercetin and rutin) have been electrochemically monitored. It has been shown that catechin takes one atom of metal per molecule; quercetin takes two atoms, and rutin is able to take up to three atoms. Not all ligands bind metals equally strong, and weakly bonded metals can be distinguished. Zn shows a sluggish kinetics and, at the same time, the highest conditional formation constants. The method could be applied to a real sample. Theoretical models are proposed for the most favourable compounds.

  18. Green tea extract only affects markers of oxidative status postprandially: lasting antioxidant effect of flavonoid-free diet

    DEFF Research Database (Denmark)

    Young, J.F.; Dragsted, Lars Ove; Haraldsdottir, J.; Daneshvar, B.; Kall, M.A.; Loft, S.; Nilsson, L.; Nielsen, S.E.; Mayer, B.; Skibsted, L.H.; Huynh-Ba, T.; Hermetter, A.; Sandstrom, B.

    2002-01-01

    Epidemiological studies suggest that foods rich in flavonoids might reduce the risk of cardiovascular disease and cancer. The objective of the present study was to investigate the effect of green tea extract (GTE) used as a food antioxidant on markers of oxidative status after dietary depletion of...... flavonoids and catechins. The study was designed as a 2x3 weeks blinded human cross-over intervention study (eight smokers, eight non-smokers) with GTE corresponding to a daily intake of 18.6 mg catechins/d. The GTE was incorporated into meat patties and consumed with a strictly controlled diet otherwise low...

  19. Suppression of cytochrome P450 1A1 expression induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in mouse hepatoma hepa-1c1c7 cells treated with serum of (-)-epigallocatechin-3-gallate- and green tea extract-administered rats.

    Science.gov (United States)

    Fukuda, Itsuko; Tsutsui, Miki; Sakane, Iwao; Ashida, Hitoshi

    2009-05-01

    The suppression of cytochrome P450 1A1 (CYP1A1) expression was examined in mouse hepatoma Hepa-1c1c7 cells treated with serum prepared from (-)-epigallocatechin-3-gallate- and green tea extract-administered rats. Catechins were found in the rat plasma after the administration. In Hepa-1c1c7 cells, 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced CYP1A1 expression was suppressed by treatment with the rat serum. It is concluded that catechins can possibly modulate CYP1A1 expression. PMID:19420696

  20. Environ: E00813 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00813 Hawthorn Medicinal herb OPC, Hyperin [CPD:C10073], Vitexin [CPD:C01460], Cat...echin [CPD:C06562] Crataegus monogyna [TAX:140997] Rosaceae Hawthorn leaves, flower, fruit Medicinal herbs [BR:br08322] Dicot plants: rosids Rosaceae (rose family) E00813 Hawthorn ...

  1. Retention of tannin-C is associated with decreased soluble-N and increased cation exchange capacity in a broad range of soils

    Science.gov (United States)

    Phenolic plant compounds, called tannins, can be retained by soil and affect nutrient cycling but have been studied in only a few soils. Soils (0-10 cm) from locations across the United States and Canada were treated with water (Control) or solutions containing procyanidin, catechin, tannic acid, ß-...

  2. Enhanced UV-B radiation may lead to the decrease of specific phenolic compounds in Norway spruce needles

    Czech Academy of Sciences Publication Activity Database

    Urban, Otmar; Vrchotová, Naděžda; Tříska, Jan; Marek, Michal V.

    2008-01-01

    Roč. 17, č. 5 (2008), s. 564-567. ISSN 1018-4619 R&D Projects: GA MŠk 2B06068 Institutional research plan: CEZ:AV0Z60870520 Keywords : 4-hydroxyacetophenone * catechin * Norway spruce * picein * screening pigments * ultraviolet radiation Subject RIV: ED - Physiology Impact factor: 0.463, year: 2008

  3. Correlation of antioxidants and antioxidant enzymes to oxygen radical scavenging activities in berries

    Science.gov (United States)

    Berry fruits contain high levels of antioxidant compounds. In addition to the usual nutrients such as vitamins and minerals, berry fruits are also rich in flavonols, anthocyanidins, proanthocyanidins, catechins, flavones, and their glycosides. These antioxidants are capable of performing a number of...

  4. Dietary A- and B-type procyanidins : characterization and biofunctional potential of an abundant and diverse group of phenolics

    NARCIS (Netherlands)

    Appeldoorn, M.M.

    2009-01-01

    Procyanidins (PCs) are phenolic compounds that belong to the class of flavonoids and are oligomers of monomeric (epi)catechin units. These monomeric units can be linked to each other by a single C4-C8 or C4-C6 linkage, which is referred to as B-type. Besides these single linkages an additional ether

  5. Chromatographic profiles of Ginkgo biloba leaves and selected products

    Science.gov (United States)

    An LC-DAD-ESI/MS method was developed to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves and selected G. biloba products. The method was used to identify 46 glycosylated flavonols and flavones, 3 free flavonol aglycones, catechin, 10 biflavones, a dihy...

  6. Quantification of Tea Flavonoids by High Performance Liquid Chromatography

    Science.gov (United States)

    Freeman, Jessica D.; Niemeyer, Emily D.

    2008-01-01

    We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

  7. Ultra-high-performance liquid chromatography profiling method for chemical screening of proanthocyanidins in Czech hops

    Czech Academy of Sciences Publication Activity Database

    Olšovská, J.; Kameník, Zdeněk; Čejka, P.; Jurková, M.; Mikyška, A.

    2013-01-01

    Roč. 116, NOV (2013), s. 919-926. ISSN 0039-9140 R&D Projects: GA MŠk(CZ) EE2.3.30.0003 Institutional support: RVO:61388971 Keywords : Flavan-3-ol * Catechin * Hops Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.511, year: 2013

  8. Drug: D06679 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D06679 Crude, Drug Gambir (JP16); Powdered gambir (JP16); Gamibir (TN) (+)-Catechin...edicine formulations 51 Crude drugs 510 Crude drugs 5100 Crude drugs D06679 Gambir (JP16); Powdered gambir (...nd expectorants D06679 Gambir; Powdered gambir; Gamibir Drugs for external use Drugs for external use D06679 *Gambir; Powdered

  9. Competitive kinetics as a tool to determine rate constants for reduction of ferrylmyoglobin by food components

    DEFF Research Database (Denmark)

    Jongberg, Sisse; Lund, Marianne Nissen; Pattison, David I.;

    2016-01-01

    . This approach allows determination of apparent rate constants for the oxidation of proteins by haem proteins of relevance to food oxidation and should be applicable to other systems. A similar approach has provided approximate apparent rate constants for the reduction of MbFe(IV)=O by catechin and...

  10. The influence of organic and conventional crop management, variety and year on the yield and flavonoid level in common buckwheat groats

    Czech Academy of Sciences Publication Activity Database

    Kalinová, J.; Vrchotová, Naděžda

    2011-01-01

    Roč. 127, č. 2 (2011), s. 602-608. ISSN 0308-8146 Institutional research plan: CEZ:AV0Z60870520 Keywords : Fagopyrum esculentum * Rutin * Epicatechin * Catechin * Epicatechin gallate * Yield * TGW * Organic farming Subject RIV: EH - Ecology, Behaviour Impact factor: 3.655, year : 2011

  11. Alkaloid and Phenolic Compounds of Rafflesia hasseltii Suringar and its host Tetrastigma leucostaphylum (Dennst.) Alston ex Mabb. in Bukit Tigapuluh National Park, Riau: A Preliminary Study

    OpenAIRE

    NERY SOFIYANTI; NINIK NIHAYATUL WAHIBAH; DEDEK PURWANTO; EDY SYAHPUTRA; KAMARUDIN MAT-SALLEH

    2008-01-01

    Two alkaloid compounds (nicotine and caffeine) together with three phenolic compounds (catechin, proanthocyanidin and phenolic acid) were firstly detected in Rafflesia hasseltii and its host, Tetrastigma leucostaphylum in Bukit Tigapuluh National Park, Riau. The content of all compounds is higher in R. hasseltii than its host.

  12. In vitro antioxidant and pancreatic α-amylase inhibitory activity of isolated fractions from water extract of Qingzhuan tea.

    Science.gov (United States)

    Cheng, Qian; Cai, Shengbao; Ni, Dejiang; Wang, Ruojun; Zhou, Feng; Ji, Baoping; Chen, Yuqiong

    2015-02-01

    In the present work, Qingzhuan tea, a unique dark tea produced by post-fermentation technology, was selected to investigate its antioxidant and pancreatic α-amylase inhibiting activities. Water extract of Qingzhuan tea was successively isolated by solvent partitioning procedures to obtain chloroform, ethyl acetate, n-butanol, sediment and residual aqua fractions. Of different fractions, the ethyl acetate fraction (QEF) had the highest total polyphenols and catechins contents, demonstrated the strongest DPPH radical scavenging activity and exhibited the greatest inhibitory effect on porcine pancreatic α-amylase activity in vitro. Further separation of QEF by a Sephadex LH-20 column generated eight subfractions (QEF1-QEF8), with QEF8 being the most active subfraction based on the assays above mentioned. The major active components in QEF8 were identified as catechins EGCG and ECG by LC-MS analysis, with contents of 22.29 % and 11.11 % respectively. Inhibitory effects of catechin standards EGCG and ECG on porcine pancreatic α-amylase activity were also observed. In conclusion, Qingzhuan tea or its water extract could be potentially used as complementary therapy ingredients for diabetes treatment through lowering postprandial blood glucose, and catechins EGCG and ECG may be the most efficient components in the water extract. PMID:25694702

  13. Procyanidins in Lotus L. genotypes grown in soil with different saturations of aluminum

    Directory of Open Access Journals (Sweden)

    Sílvia Ortiz Chini

    2016-02-01

    Full Text Available Condensed tannins are formed by monomers of procyanidins and prodelfinidins, where the proportion and concentration of their monomers varies according to the plant species and environmental conditions. In Lotus spp., condensed tannins prevent tympanism in ruminants that feed on them. This study aimed to evaluate the concentration of procyanidins and their monomers, catechin and epicatechin in the genotypes of Lotus L. grown in soil with different saturations of aluminum. A two-factor (genotype × Al saturation assay was performed, where the genotypes São Gabriel, Ganador, and UFRGS (Lotus corniculatus L.; Serrano (Lotus uliginosus; and El Rincón (Lotus subbiflorus were cultivated in soil with an Al saturation of 0-20%. The procyanidins were evaluated using high-performance liquid chromatography, which was previously validated for catechin and epicatechin. The concentration of procyanidins and the proportion of epicatechin:catechin were affected by the genotype × environment interaction. In L. corniculatus and L. subbiflorus, the concentration of procyanidin was significantly higher when they were grown in the soil with an Al saturation of 20% compared to that when they were grown in the soil with 0% Al saturation, but the opposite effect was observed in L. uliginosus. The proportion of epicatechin:catechin decreased in plants grown in soil without Al, and only the UFRGS genotype maintained a similar proportion under both the soil acidity conditions. The predominant monomer was epicatechin, which varied from 57% to 75% according to the soil in which the plants were grown.

  14. Application of microwave energy in the manufacture of enhanced-quality green tea.

    Science.gov (United States)

    Gulati, Ashu; Rawat, Renu; Singh, Brajinder; Ravindranath, S D

    2003-07-30

    Green tea manufacture was standardized with respect to the inactivation of polyphenol oxidase (PPO), rolling, and drying for quality manufacture. Inactivation of PPO by parching, steaming, microwave heating, and oven heating was monitored in tea shoots. The inactivated shoots were rolled under regimens of high and low pressures and dried by microwave heating, oven heating, or sun-drying; total phenols and catechins were estimated. Parched and sun-dried teas contained the lowest levels of total phenols and catechins, and their infusions were dull in color with a slightly burnt odor. Microwave-inactivated and-dried teas showed the highest levels of total phenols and catechins, and their infusions were bright in color and sweet in taste with a subtle pleasant odor. In steam-inactivated and oven/microwave-dried teas, total phenol and catechin contents were intermediate between parched and sun-dried teas and microwave-inactivated and microwave-dried teas, and their infusions were bright with a umami taste. PMID:14705910

  15. Environ: E00762 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00762 Witch hazel Medicinal herb Tannin, (+)-Catechin [CPD:C06562], Proanthocyanid...ana [TAX:4397] Hamamelidaceae Witch hazel leaves Major component: Tannin Medicinal herbs [BR:br08322] Dicot plants: others Hamamelidaceae (witch-hazel family) E00762 Witch hazel ...

  16. Overview of Antibacterial, Antitoxin, Antiviral, and Antifungal Activities of Tea Flavonoids and Teas

    Science.gov (United States)

    Tea leaves produce secondary metabolites, organic compounds that are involved in the defense of the plants against invading pathogens including insects, bacteria, fungi, and viruses. These metabolites include polyphenolic compounds, the six so-called catechins, and the methyl-xanthine alkaloids caf...

  17. Investigation of the free radical scavenging activity of Ginkgo biloba L. leaves.

    Science.gov (United States)

    Ellnain-Wojtaszek, M; Kruczyński, Z; Kasprzak, J

    2003-02-01

    The free radical scavenging activity of methanolic, ethanolic and aqueous extracts from Ginkgo biloba leaves, has been determined by EPR (electron paramagnetic resonance) using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging method. The investigation has also included selected constituents of G. biloba leaves, protocatechuic and p-coumaric acids, quercetin, rutin, isoginkgetin and (+)-catechin. PMID:12628386

  18. Effects of Metabolites Produced from (-)-Epigallocatechin Gallate by Rat Intestinal Bacteria on Angiotensin I-Converting Enzyme Activity and Blood Pressure in Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Takagaki, Akiko; Nanjo, Fumio

    2015-09-23

    Inhibitory activity of angiotensin I-converting enzyme (ACE) was examined with (-)-epigallocatechin gallate (EGCG) metabolites produced by intestinal bacteria, together with tea catechins. All of the metabolites showed ACE inhibitory activities and the order of IC50 was hydroxyphenyl valeric acids > 5-(3,4,5-trihydroxyphenyl)-γ-valerolactone (1) > trihydroxyphenyl 4-hydroxyvaleric acid ≫ dihydroxyphenyl 4-hydroxyvaleric acid ≫ 5-(3,5-dihydroxyphenyl)-γ-valerolactone (2). Among the catechins, galloylated catechins exhibited stronger ACE inhibitory activity than nongalloylated catechins. Furthermore, the effects of a single oral intake of metabolites 1 and 2 on systolic blood pressure (SBP) were examined with spontaneously hypertensive rats (SHR). Significant decreases in SBP were observed between 2 h after oral administration of 1 (150 mg/kg in SHR) and the control group (p = 0.002) and between 4 h after administration of 2 (200 mg/kg in SHR) and the control group (p = 0.044). These results suggest that the two metabolites have hypotensive effects in vivo. PMID:26323573

  19. Epigallocatechin gallate remodels fibrils of Lattice Corneal Dystrophy protein, facilitating proteolytic degradation and preventing formation of membrane-permeabilizing species

    DEFF Research Database (Denmark)

    Stenvang, Marcel; Christiansen, Gunna; Otzen, Daniel Erik

    2016-01-01

    with destabilizing mutations in the fourth fasciclin 1 (Fas1-4) domain of TGFBIp. The green tea compound Epigallo-catechin gallate (EGCG) has been found to inhibit fibril formation of various amyloidogenic proteins in vitro. In this study we investigated the effect of EGCG as a potential treatment in...

  20. The Dark-Purple Tea Cultivar 'Ziyan' Accumulates a Large Amount of Delphinidin-Related Anthocyanins.

    Science.gov (United States)

    Lai, Yun-Song; Li, Sha; Tang, Qian; Li, Huan-Xiu; Chen, Shen-Xiang; Li, Pin-Wu; Xu, Jin-Yi; Xu, Yan; Guo, Xiang

    2016-04-01

    Recently, we developed a novel tea cultivar 'Ziyan' with distinct purple leaves. There was a significant correlation between leaf color and anthocyanin pigment content in the leaves. A distinct allocation of metabolic flow for B-ring trihydroxylated anthocyanins and catechins in 'Ziyan' was observed. Delphinidin, cyanidin, and pelargonidin (88.15 mg/100 g FW in total) but no other anthocyanin pigments were detected in 'Ziyan', and delphinidin (70.76 mg/100 g FW) was particularly predominant. An analysis of the catechin content in 'Ziyan' and eight other cultivars indicated that 'Ziyan' exhibits a preference for synthesizing B-ring trihydroxylated catechins (with a proportion of 74%). The full-length cDNA sequences of flavonoid pathway genes were isolated by RNA-Seq coupled with conventional TA cloning, and their expression patterns were characterized. Purple-leaved cultivars had lower amounts of total catechins, polyphenols, and water extract than ordinary non-anthocyanin cultivars but similar levels of caffeine. Because dark-purple-leaved Camellia species are rare in nature, this study provides new insights into the interplay between the accumulations of anthocyanins and other bioactive components in tea leaves. PMID:26996195

  1. Effect of boldo (Peumus boldus Molina) infusion on lipoperoxidation induced by cisplatin in mice liver.

    Science.gov (United States)

    Fernández, J; Lagos, P; Rivera, P; Zamorano-Ponce, E

    2009-07-01

    Peumus boldus Molina (Monimiaceae), commonly referred to as 'boldo', is used in traditional Chilean medicine to treat hepatic and gastrointestinal diseases. Its leaves are rich in antioxidant compounds, principally alkaloids and flavonoids. This study evaluates the protective effect of a complete boldo leaf infusion on lipoperoxidation (MDA determination at 532 nm) induced by cisplatin in mice liver. To determine if the observed effect can be explained by the action of boldine or catechin, each compound was studied separately. The mice were divided into 8 groups (n = 6): (I) not treated; (II) treated with cisplatin 6 mg/Kg b.w.; (III) treated with boldo leaf infusion 5%; (IV) pretreated with boldo leaf infusion 5% and treated with cisplatin 6 mg/Kg b.w.; (V) treated with boldine 50 mg/Kg b.w.; (VI) pretreated with boldine 50 mg/Kg b.w. and treated with cisplatin 6 mg/kg.b.w.; (VII) treated with catechin; and (VIII) pretreated with catechin 50 mg/Kg b.w. and treated with cisplatin 6 mg/Kg b.w. As expected, the treatment with cisplatin significantly increased (p < 0.01) lipoperoxidation in comparison with the non-treated group. Pretreatment with boldo leaf infusion significantly diminished (p < 0.05) the lipoperoxidation induced by cisplatin with respect to the animals not pretreated with the infusion. The pretreatments with boldine and catechin significantly diminished (p < 0.05) the lipoperoxidation induced by cisplatin with respect to the group treated only with cisplatin. The results suggest that the boldo infusion is acting as a protector with respect to the oxidative hepatic damage caused by cisplatin, and that this protective ability would be due to the presence in the infusion of the natural antioxidants boldine and principally catechin. These findings suggest the potential use of the infusion as a chemoprotector. PMID:19145575

  2. EFFECT OF GREEN TEA AND ITS COMPONENTS ON BODY WEIGHT, FAT ACCUMULATION AND ACTIVITY OF HEPATIC FAT METABOLISM RELATED ENZYMES IN MICE%绿茶及其成分对小鼠体重、脂肪沉积和肝脏脂肪代谢酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    郑国栋; 黎冬明; 张清峰

    2012-01-01

    Objective To investigate the anti-obesity mechanism of green tea and its components in mice. Method Fifty female Kunming mice were randomly assigned to 5 groups and fed on commercial powder diets containing none (control), 2% green tea, 0.05% caffeine, 0.3% catechins and 0.05% caffeine + 0.3% catechins for 8 w respectively. Liver and intraperitoneal adipose tissues (IPAT) were weighed at the end of experiment. Serum levels of glucose, triglycerides (TG), total cholesterols, leptin and insulin, and lipids in liver were measured. Fatty acid synthese (FAS), carnitine acyltransferase (CAT) and acyl-CoA oxidase (ACO) in liver were determined. Results The body weight gain and IPAT weight were significantly reduced by green tea, caffeine and caffeine + catechins. Serum TG and leptin concentrations were significantly decreased by caffeine + catechins. Green tea, catechins and caffeine + catechins reduced TG level in liver. Caffeine + catechins significantly reduced FAS activity, and remarkably increased CAT and ACO activities in liver. Conclusion Caffeine + catechins can inhibit fat accumulation and body weight gain in mice through regulating fat metabolism related enzymes activities. Moreover, caffeine and catechins possess synergistic anti-obesity effect.%目的 研究绿茶及其成分的减肥作用机制.方法 50只雌性昆明小鼠随机分成5组,分别为对照组、2%绿茶组、0.05%咖啡碱组、0.3%儿茶素组及0.05%咖啡碱+0.3%儿茶素组.混合饲料投喂8w后,摘取肝脏和腹腔脂肪(IPAT)并称重.分析血清中血糖、甘油三酯(TG)、总胆固醇、瘦素及胰岛素浓度和肝脏中脂类含量.测定肝脏中脂肪酸合成酶(FAS)、肉毒碱脂酰转移酶(CAT)和酰基辅酶A氧化酶(ACO)的活性.结果 绿茶、咖啡碱、咖啡碱+儿茶素组体重增加和IPAT重量比对照组明显减少,特别是咖啡碱+儿茶素效果极显著.咖啡碱+儿茶素显著降低血中TG和瘦素浓度.绿茶、儿茶素、咖啡

  3. Survey of commercially available chocolate- and cocoa-containing products in the United States. 2. Comparison of flavan-3-ol content with nonfat cocoa solids, total polyphenols, and percent cacao.

    Science.gov (United States)

    Miller, Kenneth B; Hurst, W Jeffrey; Flannigan, Nancy; Ou, Boxin; Lee, C Y; Smith, Nancy; Stuart, David A

    2009-10-14

    A survey of a broad range of chocolate- and cocoa-containing products marketed in the United States was conducted to provide a more detailed analysis of flavan-3-ol monomers, oligomers, and polymers, which can be grouped into a class of compounds called procyanidins. Samples consisted of the three or four top-selling products within the following six categories: natural cocoa powder, unsweetened baking chocolate, dark chocolate, semisweet baking chips, milk chocolate, and chocolate syrup. Composite samples were characterized for percent fat (% fat), percent nonfat cocoa solids (% NFCS), antioxidant level by ORAC, total polyphenols, epicatechin, catechin, total monomers, and flavan-3-ol oligomers and polymers (procyanidins). On a gram weight basis epicatechin and catechin content of the products follow in decreasing order: cocoa powder > baking chocolate > dark chocolate = baking chips > milk chocolate > chocolate syrup. Analysis of the monomer and oligomer profiles within product categories shows there are two types of profiles: (1) products that have high monomers with decreasing levels of oligomers and (2) products in which the level of dimers is equal to or greater than the monomers. Results show a strong correlation (R(2) = 0.834) of epicatechin to the level of % NFCS and also very good correlations for N = 2-5 oligomers to % NFCS. A weaker correlation was observed for catechin to % NFCS (R(2) = 0.680). Other analyses show a similar high degree of correlation with epicatechin and N = 2-5 oligomers to total polyphenols, with catechin being less well correlated to total polyphenols. A lesser but still good correlation exists between the calculated percent cacao (calcd % cacao) content, a proxy for percent cacao, and these same flavanol measures, with catechin again showing a lesser degree of correlation to calcd % cacao. Principal component analysis (PCA) shows that the products group discretely into five classes: (1) cocoa powder, (2) baking chocolate, (3) dark

  4. Effect of the addition of flavan-3-ols on the HPLC-DAD salivary-protein profile.

    Science.gov (United States)

    Quijada-Morín, Natalia; Crespo-Expósito, Carlos; Rivas-Gonzalo, Julián C; García-Estévez, Ignacio; Escribano-Bailón, María Teresa

    2016-09-15

    The interaction between monomeric flavan-3-ols and salivary proteins has been studied using HPLC-DAD. A chromatographic method has been described and seven protein fractions were collected. The peptides and proteins present in each fraction have been identified using nLC-MS-MS analysis. The interaction between saliva and catechin, epicatechin and gallocatechin has been studied. These compounds interact in a discriminated way with salivary proteins: catechin causes a decrease of some fractions, epicatechin causes the decrease or increase of fractions while gallocatechin seems to cause an increase of two fractions. This variable behavior is explained, for the decrease in the chromatographic area, by the precipitation of salivary proteins and, for the increase of the area, by the formation of soluble complexes and/or for the formation of new peaks. PMID:27080905

  5. Condensed tannins from the bark of Guazuma ulmifolia Lam. (Sterculiaceae)

    International Nuclear Information System (INIS)

    From the bark of Guazuma ulmifolia Lam. (Sterculiaceae), nine compounds were isolated and identified: ent-catechin, epicatechin, ent-gallocatechin, epigallocatechin, epiafzelechin-(4β?8)-epicatechin, epicatechin-(4β?8)-catechin (procyanidin B1), epicatechin-(4β?8)-epicatechin (procyanidin B2), epicatechin-(4β?8)-epigallocatechin, and the new compound 4'-O-methyl-epiafzelechin. Their structures were elucidated on the basis of spectral and literature data. HPLC fingerprint analysis of the semipurified extract was performed on a C18 column, with a mixture of acetonitrile (0.05% trifluoroacetic acid):water (0.05% trifluoroacetic acid) (v/v) with a flow rate of 0.8 mL min-1. The sample injection volume was 100 μL and the wavelength was 210 nm. (author)

  6. Condensed tannins from the bark of Guazuma ulmifolia Lam. (Sterculiaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Gisely C.; Rocha, Juliana C.B.; Mello, Joao C.P. de [Universidade Estadual de Maringa (UEM), PR (Brazil). Programa de Pos-graduacao em Ciencias Farmaceuticas], e-mail: mello@uem.br; Almeida, Glalber C. de [Universidade Estadual de Maringa (UEM), PR (Brazil)

    2009-07-01

    From the bark of Guazuma ulmifolia Lam. (Sterculiaceae), nine compounds were isolated and identified: ent-catechin, epicatechin, ent-gallocatechin, epigallocatechin, epiafzelechin-(4{beta}?8)-epicatechin, epicatechin-(4{beta}?8)-catechin (procyanidin B1), epicatechin-(4{beta}?8)-epicatechin (procyanidin B2), epicatechin-(4{beta}?8)-epigallocatechin, and the new compound 4'-O-methyl-epiafzelechin. Their structures were elucidated on the basis of spectral and literature data. HPLC fingerprint analysis of the semipurified extract was performed on a C18 column, with a mixture of acetonitrile (0.05% trifluoroacetic acid):water (0.05% trifluoroacetic acid) (v/v) with a flow rate of 0.8 mL min-1. The sample injection volume was 100 {mu}L and the wavelength was 210 nm. (author)

  7. Antioxidant-guided isolation and mass spectrometric identification of the major polyphenols in barley (Hordeum vulgare) grain.

    Science.gov (United States)

    Gangopadhyay, Nirupama; Rai, Dilip K; Brunton, Nigel P; Gallagher, Eimear; Hossain, Mohammad B

    2016-11-01

    In the present study, the relative contribution of individual/classes of polyphenols in barley, to its antioxidant properties, was evaluated. Flash chromatography was used to fractionate the total polyphenol extract of Irish barley cultivar 'Irina', and fractions with highest antioxidant properties were identified using total phenolic content and three in vitro antioxidant assays: DPPH, FRAP, and ORAC. Flavanols (catechin, procyanidin B, prodelphinidin B, procyanidin C) and a novel substituted flavanol (catechin dihexoside, C27H33O16(-), m/z 613.17), were identified as constituents of the fraction with highest antioxidant capacity. Upon identification of phenolics in the other active fractions, the order of most potent contributors to observed antioxidant capacity of barley extract were, flavanols>flavonols (quercetin)>hydroxycinnamic acids (ferulic, caffeic, coumaric acids). The most abundant polyphenol in the overall extract was ferulic acid (277.7μg/gdw barley), followed by procyanidin B (73.7μg/gdw barley). PMID:27211640

  8. Phenolic Compounds of Pinus brutia Ten.: Chemical Investigation and Quantitative Analysis Using an Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry with Electrospray Ionization Source

    Directory of Open Access Journals (Sweden)

    İbrahim Kıvrak

    2013-08-01

    Full Text Available In this study, phenolic content of Pinus brutia ’s bark was examined using an ultra-performance liquid chromatography tandem mass spectrometry with electrospray ionization source (UPLC-ESI-MS/MS working in multiple reaction monitoring mode. U ltrasonic extraction method with 50% ethanol solution was used for the extraction of bark. The bark of Pinus brutia consisted of 15 compounds: gallic acid, gentisic acid, protocatechuic acid, 4-hydroxy benzoic acid, catechin hydrate, vanillic acid, caffeic acid, vanillin, p-coumaric acid, ferulic acid, myricetin, resveratrol, luteolin, naringenin, kaempferol. Major compound detected was catechin hydrate (28.305 mg 100 g -1 extract. The phenolic compounds of Pinus brutia extract and pycnogenol were compared, and it is shown that both of them consisted of considerable amount of phenolic compounds.

  9. Simultaneous kinetic spectrometric determination of three flavonoid antioxidants in fruit with the aid of chemometrics

    Science.gov (United States)

    Sun, Ruiling; Wang, Yong; Ni, Yongnian; Kokot, Serge

    2014-03-01

    A simple, inexpensive and sensitive kinetic spectrophotometric method was developed for the simultaneous determination of three anti-carcinogenic flavonoids: catechin, quercetin and naringenin, in fruit samples. A yellow chelate product was produced in the presence neocuproine and Cu(I) - a reduction product of the reaction between the flavonoids with Cu(II), and this enabled the quantitative measurements with UV-vis spectrophotometry. The overlapping spectra obtained, were resolved with chemometrics calibration models, and the best performing method was the fast independent component analysis (fast-ICA/PCR (Principal component regression)); the limits of detection were 0.075, 0.057 and 0.063 mg L-1 for catechin, quercetin and naringenin, respectively. The novel method was found to outperform significantly the common HPLC procedure.

  10. Measurement of the G values of hydrogen peroxide in the reactions of typical flavonoids with superoxide anion radicals. Pt.2

    International Nuclear Information System (INIS)

    γ irradiated rutin-, catechin-and baicalin-HCOONa aqueous solutions saturated with N2O:O2 = 4:1 were eluted through alumina columns and the G values of hydrogen peroxide generated in the solutions were measured. Different results from former works were obtained and the reasons of the difference were discussed. A precise method was established as follows: hydrogen peroxide should be separated from flavonoids by passing the flavonoids solution through alumina columns before the measurement and the amount of hydrogen peroxide generated from self-oxidation of the flavonoids should be deducted. The G values of hydrogen peroxide in γ irradiated rutin-, catechin- and baicalin- aqueous solution saturated with N2O:O2= 4:1 were determined to be 8.3 +- 0.2, 5.6 +- 0.2, and 7.8 +- 0.2, separately

  11. Partitioning of selected antioxidants in mayonnaise

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Schwarz, K.; Stockmann, H.; Meyer, Anne S.; Adler-Nissen, Jens

    1999-01-01

    This study examined partitioning of alpha-, beta-, and gamma- tocopherol and six polar antioxidants (Trolox, ferulic acid, caffeic acid, propyl gallate, gallic acid, and catechin) in mayonnaise. Partitioning of antioxidants between different phases was determined after separation of mayonnaise by...... "precipitate" (7-34% and 2-7%, respectively). This indicated entrapment of antioxidants at the oil-water interface in mayonnaise. The results signify that antioxidants partitioning into different phases of real food emulsions may vary widely......This study examined partitioning of alpha-, beta-, and gamma- tocopherol and six polar antioxidants (Trolox, ferulic acid, caffeic acid, propyl gallate, gallic acid, and catechin) in mayonnaise. Partitioning of antioxidants between different phases was determined after separation of mayonnaise by...... either (a) centrifugation + ultracentrifugation or (b) centrifugation + dialysis. Antioxidants partitioned in accordance with their chemical structure and polarity: Tocopherols were concentrated in the oil phase (93-96%), while the proportion of polar antioxidants in the oil phase ranged from 0% (gallic...

  12. Studies on the nature of anti-platelet aggregatory factors in the seeds of the Amazonian Herb Guarana (Paullinia cupana).

    Science.gov (United States)

    Subbiah, M T Ravi; Yunker, R

    2008-03-01

    Guarana (Paullinia cupana) is a popular herb native to the Amazon Basin and used extensively in soft drinks in Brazil, other Latin American countries, and more recently in the United States. Extracts derived from the dried seeds of guarana possess strong anti-platelet aggregatory properties. In this study, an active fraction containing this activity was purified and analyzed by high-performance liquid chromatography/mass spectrometry (HPLC/MS) techniques. It was noted that this fraction contains catechins, epicatechins, and their dimers, with a small amount of caffeine. It is suggested that complexes containing caffeine and catechins (and their dimers) might be responsible for anti-platelet aggregatory activity in guarana seeds and might offer health benefits towards decreasing risk of thrombosis and cardiovascular disease. PMID:18791978

  13. Regeneration of phenolic antioxidants from phenoxyl radicals: An ESR and electrochemical study of antioxidant hierarchy

    DEFF Research Database (Denmark)

    Jørgensen, Lars V.; Madsen, Helle L.; Thomsen, Marianne K.; Dragsted, Lars O.; Skibsted, Leif H.

    1999-01-01

    Radicals from the flavonoids quercetin, (+)-catechin, (+/-)-taxifolin and luteolin, and from all-rac-alpha-tocopherol have been generated electrochemically by one-electron oxidation in deaerated dimethylformamide (DMF), and characterised by electron spin resonance spectroscopy (ESR) after spin......-trapping by 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). Simulations of the ESR spectrum based on estimated coupling constants of the spin-trapped quercetin radical, confirmed that this antioxidant radical is oxygen-centered. The complex mixture of radicals, quinoid intermediates and stable two-electron oxidation...... antioxidants from their oxidation products with a regeneration index (defined as moles regenerated of the oxidised phenolic antioxidant divided with moles of all-rac-alpha-tucopherol consumed) of 0.90 +/- 0.16 for quercetin, 0.48 +/- 0.11 for (+)-catechin, 0.48 +/- 0.06 for (+/-)-taxifolin and 0.50 +/- 0...

  14. Natural fermentation of lentils. Influence of time, concentration and temperature on protein content, trypsin inhibitor activity and phenolic compound content.

    Science.gov (United States)

    Tabera, J; Frias, J; Estrella, I; Villa, R; Vidal-Valverde, C

    1995-12-01

    Lentil (Lens culinaris var. vulgaris) flour was naturally fermented for 4 days at different temperatures (28 degrees C, 35 degrees C and 42 degrees C) and concentrations (79 milligrams, 150 milligrams and 221 milligrams). Samples were analysed to establish the changes of total protein content and in vitro protein digestibility, trypsin inhibitor activity (TIA) and phenolic compound content during natural fermentation of lentils. The preparation of lentil flour suspensions to be fermented caused a slight increase in total protein and in vitro protein digestibility content, a decrease of TIA and a sharp decrease the tannin/catechin ratio. During the whole fermentation procedure, the minimum initial lentil concentration and temperature used (79 milligrams, 28 degrees C) achieved the maximum protein content and the lowest tannin/catechin ratio. The TIA was more affected by temperature than by concentration, and a 62.5% reduction was observed at 42 degrees C and 79 milligrams. PMID:8585337

  15. Compositional variation among black tea across geographies and their potential influence on endothelial nitric oxide and antioxidant activity.

    Science.gov (United States)

    Dias, Paul Mark; Changarath, Jayashree; Damodaran, Anita; Joshi, Manoj Kumar

    2014-07-16

    Black tea (C. sinensis) consumption is well associated with enhanced endothelial function (EF) and reduced cardiovascular (CV) risk. This clinical end benefit is endorsed to flavonoids in tea. The black tea flavonoid composition varies across geographies and may impact its health benefits. Moreover, the underlying functional species and a precise working mechanism responsible for the observed health benefit also remain to be investigated. In this Article, we investigated the effect of black teas from various geographies (WoBTs) on different working mechanisms (antioxidant potential and endothelial function) proposed to influence certain risk factors of CVH, in vitro. Pearson correlation analysis showed that the antioxidant benefits are fairly influenced by majority of tea actives such as catechins, theaflavins, thearubigins, and phenolic acids, while NO potentiating effects are mainly regulated by catechins in black tea. The data also suggest that the net vascular function benefit of black tea is majorly influenced by NO enhancement, while mildly contributed by its antioxidant benefit. PMID:24990074

  16. New insights into the mechanisms of polyphenols beyond antioxidant properties; lessons from the green tea polyphenol, epigallocatechin 3-gallate

    Directory of Open Access Journals (Sweden)

    Hae-Suk Kim

    2014-01-01

    Full Text Available Green tea is rich in polyphenol flavonoids including catechins. Epigallocatechin 3-gallate (EGCG is the most abundant and potent green tea catechin. EGCG has been extensively studied for its beneficial health effects as a nutriceutical agent. Based upon its chemical structure, EGCG is often classified as an antioxidant. However, treatment of cells with EGCG results in production of hydrogen peroxide and hydroxyl radicals in the presence of Fe (III. Thus, EGCG functions as a pro-oxidant in some cellular contexts. Recent investigations have revealed many other direct actions of EGCG that are independent from anti-oxidative mechanisms. In this review, we discuss these novel molecular mechanisms of action for EGCG. In particular, EGCG directly interacts with proteins and phospholipids in the plasma membrane and regulates signal transduction pathways, transcription factors, DNA methylation, mitochondrial function, and autophagy to exert many of its beneficial biological actions.

  17. Substrate specifity and inhibitors of polyphenol oxidase in aspect of darkening of fresh and frozen mushrooms (Agaricus bisporus (Lange Sing.

    Directory of Open Access Journals (Sweden)

    Janusz Czapski

    2013-12-01

    Full Text Available Activity of mushroom polyphenol oxidase (PPO toward 6 substrates and inhibitory effect of cysteine, 2-mercaptoethanol, benzoic acid and sodium metabisulphite were determined. The o-diphenols which appeared to be the best substrates were: catechin, DOPA (L-3,4-dihydro-xyphenylalanine and chlorogcnic acid. Affinity of PPO crude preparation substrates to enzyme, expressed as inverse value of Michaelis constant was lower then affinity of catechol. Inhibitory effect depended on specifity of inhibitors and their concentration. Electrophoretic patterns of PPO of mushrooms reveals slow and fast moving 4 isoforms when DOPA was used as a substrate, 2 bands for catechin and chlorogenic acid while only one band showed activity toward tyrosine and p-cresol.

  18. New Electrochemical Evaluation of the Antioxidant Capacity of Beverages with Polyoxometalates as Redox Probes.

    Science.gov (United States)

    Ueda, Tadaharu; Okumura, Takashi; Tanaka, Yukino; Akase, Saki; Shimamura, Tomoko; Ukeda, Hiroyuki

    2016-01-01

    A new method was developed to evaluate antioxidant activity based on the redox properties of polyoxometalates, which are partially reduced by antioxidants to generate a limiting potential. The polyoxometalates [PMo12O40](3-), [PVW11O40](4-) and [SV2W10O40]4- formed in situ were used as electrochemical probes for the new evaluation method, and their formation conditions were optimized to evaluate the antioxidant activities of gallic acid, ellagic acid, catechin, quercetin, morin, trans-ferulic acid, sesamol, α-tocopherol, δ-tocopherol and L-ascorbic acid. The observed difference between initial potential and limiting potential (ΔE) were compared with spectrophotometrically evaluated antioxidant activities. In addition, the antioxidant capacities of five beverages (Japanese green tea, concentrated catechin-containing green tea, grapefruit juice, red wine and Japanese sake) were evaluated. PMID:27506707

  19. Does overhead irrigation with salt affect growth, yield, and phenolic content of lentil plants?

    Directory of Open Access Journals (Sweden)

    Giannakoula Anastasia

    2012-01-01

    Full Text Available Overhead irrigation of lentil plants with salt (100 mM NaCl did not have any significant impact on plant growth, while chlorophyll content and chlorophyll fluorescence parameter Fv/Fm were affected. Under such poor irrigation water quality, the malondialdehyde content in leaves was increased due to the lipid peroxidation of membranes. In seeds, the total phenolic content (TPC was correlated to their total antioxidant capacity (TAC. High performance liquid chromatography-mass spectrometry (HPLC-MS detection showed that flavonoids (catechin, epicatechin, rutin, p-coumaric acid, quercetin, kaempferol, gallic acid and resveratrol appear to be the compounds with the greatest influence on the TAC values. Catechin is the most abundant phenolic compound in lentil seeds. Overhead irrigation with salt reduced the concentration of almost all phenolic compounds analyzed from lentil seed extracts.

  20. Analysis of commercial proanthocyanidins. Part 1: the chemical composition of quebracho (Schinopsis lorentzii and Schinopsis balansae) heartwood extract.

    Science.gov (United States)

    Venter, Pieter B; Sisa, Mirek; van der Merwe, Marthinus J; Bonnet, Susan L; van der Westhuizen, Jan H

    2012-01-01

    Quebracho (Schinopsis lorentzii and Schinopsis balansae) extract is an important source of natural polymers for leather tanning and adhesive manufacturing. We combined established phyto- and synthetic chemistry perspectives with electrospray mass spectrometry experiments to prove that quebracho proanthocyanidin polymers consist of an homologous series of flavan-3-ol based oligomers. The starter unit is always catechin which is angularly bonded to fisetinidol extender units. By comparison of the MS(2) fragmentation spectra of the oligomer with product ion scans of authentic catechin and robinetinidol samples, we proved that quebracho extract contains no robinetinidol, as is often reported. Quebracho proanthocyanidins have acid resistant interflavanyl bonds, due to the absence of 5-OH groups in fisetinidol, and the aDP cannot be determined via conventional thiolysis and phloroglucinolysis. We used the MS data to estimate a conservative (minimum value) aDP of 3.1. PMID:22063672

  1. Determination of quality constituents in the young leaves of albino tea cultivars.

    Science.gov (United States)

    Feng, Lin; Gao, Ming-Jun; Hou, Ru-Yan; Hu, Xiao-Yi; Zhang, Liang; Wan, Xiao-Chun; Wei, Shu

    2014-07-15

    Albino tea has received increased attention due to its brisk flavour. To identify changes in the key chemical constituents conveying important qualities to albino tea, the metabolite profiles of four albino cultivars and one green tea cultivar were analysed. Compared to the green tea control, significantly decreased contents of chlorophyll (Chl) (ptea leaves with a few exceptions, whereas increases were noted in the Chl a/b ratio and the contents of both zeaxanthin and free amino acids, including theanine. Multivariate analysis identified catechins and carotenoids as the most important contributors to the metabolic profile variance between the albino and green tea cultivars. High levels of amino acids, along with low levels of chlorophylls, catechins and caffeine, contribute to the qualities of albino tea, which include reduced astringency and bitterness, along with a strong umami taste. PMID:24594160

  2. Evaluation of the umami taste intensity of green tea by a taste sensor.

    Science.gov (United States)

    Hayashi, Nobuyuki; Chen, Roggang; Ikezaki, Hidekazu; Ujihara, Tomomi

    2008-08-27

    A method for evaluating the umami taste intensity of green tea by a taste sensor system was established. Interference in the measurement from catechins was solved by removing the catechins from sample solutions with poly(vinylpolypyrrolidone). A 5.00 mM aqueous solution of glutamic acid monosodium salt was used as the standard solution. Sensor outputs were converted into EIT uma (estimated intensity of taste concerning umami) values. One unit on the EIT uma scale was defined as the amount of the sensor output corresponding to a difference in 1.2 times the concentration of the standard substance (glutamic acid monosodium salt). The umami taste intensity of green tea was classified into six grades on the EIT uma scale. Sensory tests proved that the EIT uma value had a high correlation to the human gustatory sense. PMID:18620401

  3. New phenylpropanoid-substituted flavan-3-ols from Pu-er ripe tea.

    Science.gov (United States)

    Tao, Mu-Ke; Xu, Min; Zhu, Hong-Tao; Cheng, Rong-Rong; Wang, Dong; Yang, Chong-Ren; Zhang, Ying-Jun

    2014-08-01

    Pu-er ripe tea is a special microbial post-fermented tea made from Pu-er raw tea, a kind of green tea produced from the leaves of Camellia sinensis var. assamica. It is one of the most consumed teas in the past two decades in China, due to its special flavor, taste, and beneficial effects. This work aimed to obtain diverse catechin structures from Pu-er ripe tea, which led to the isolation of four new phenylpropanoid-substituted flavan-3-ols, puerins C-F (1-4), together with four known flavan-3-ols, (+)-catechin (5), (-)-epicatechin (6), (+/-)-gallocatechin (7), and (-)-epigallocatechin (8). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR, mass and CD spectra. Compounds 1-4, which could be formed in the post-fermentative process of Pu-er tea, were isolated for the first time from tea and Theaceae plant. PMID:25233599

  4. Phenolic compounds, organic acids and antioxidant activity of grape juices produced in industrial scale by different processes of maceration.

    Science.gov (United States)

    Lima, Marcos dos Santos; da Conceição Prudêncio Dutra, Maria; Toaldo, Isabela Maia; Corrêa, Luiz Claudio; Pereira, Giuliano Elias; de Oliveira, Débora; Bordignon-Luiz, Marilde Terezinha; Ninow, Jorge Luiz

    2015-12-01

    The effect of maceration process on the profile of phenolic compounds, organic acids composition and antioxidant activity of grape juices from new varieties of Vitis labrusca L. obtained in industrial scale was investigated. The extraction process presented a high yield without pressing the grapes. The use of a commercial pectinase resulted in an increase on extraction yield and procyanidins B1 and B2 concentrations and a decrease on turbidity and concentration of catechins. The combination of 60 °C and 3.0 mL 100 kg(-1) of enzyme resulted in the highest extraction of phenolic compounds, reducing the content of acetic acid. The juices presented high antioxidant activity, related to the great concentration of malvidin, cyanidin, catechin and caffeic, cinnamic and gallic acids. Among the bioactive compounds, the juices presented high concentration of procyanidin B1, caffeic acid and trans-resveratrol, with higher levels compared to those reported in the literature. PMID:26041208

  5. Regeneration of phenolic antioxidants from phenoxyl radicals: An ESR and electrochemical study of antioxidant hierarchy

    DEFF Research Database (Denmark)

    Jørgensen, Lars V.; Madsen, Helle L.; Thomsen, Marianne K.; Dragsted, Lars O.; Skibsted, Leif H.

    1999-01-01

    Radicals from the flavonoids quercetin, (+)-catechin, (+/-)-taxifolin and luteolin, and from all-rac-alpha-tocopherol have been generated electrochemically by one-electron oxidation in deaerated dimethylformamide (DMF), and characterised by electron spin resonance spectroscopy (ESR) after spin...... products, were for each antioxidant allowed to react with each of the four other antioxidants, and the progression of reaction followed by ESR after addition of DMPO, and the product solution further analysed by HPLC. All-rac-alpha-tocopherol was found to be most efficient in regenerating each of the other...... based on the reduction potentials determined by cyclic voltammetry under similar conditions (0.93 V for all-rac-alpha-tocopherol, 1.07 V for quercetin, 1.15 V for luteolin, 1.16 V for (+)-catechin and 1.20 V for (+/-)-taxifolin) is compared with the observed over-all regeneration (34% for quercetin, 34...

  6. Antioxidant, Biomolecule Oxidation Protective Activities of Nardostachys jatamansi DC and Its Phytochemical Analysis by RP-HPLC and GC-MS

    OpenAIRE

    Sakina Razack; Kandikattu Hemanth Kumar; Ilaiyaraja Nallamuthu; Mahadeva Naika; Farhath Khanum

    2015-01-01

    The study aimed at analyzing the metabolite profile of Nardostachys jatamansi using RP-HPLC, GC-MS and also its antioxidant, biomolecule protective and cytoprotective properties. The 70% ethanolic extract of Nardostachys jatamansi (NJE) showed the presence of polyphenols and flavonoids (gallic acid, catechin, chlorogenic acid, homovanillin, epicatechin, rutin hydrate and quercetin-3-rhamnoside) analyzed by RP-HPLC, whereas hexane extract revealed an array of metabolites (fatty acids, sesquite...

  7. PENGARUH PENAMBAHAN LAKASE DARI JAMUR TIRAM PUTIH (Pleurotus ostreatus) TERHADAP AKTIVITAS ANTIOKSIDAN TEH HIJAU [Effect of The Addition of Laccase from White Oyster Mushroom (Pleurotus ostreatus) Towards Antioxidant Activity of Green Tea

    OpenAIRE

    Tagor M. Siregar1)*; A. Herry Cahyana2); Natalia

    2012-01-01

    Laccase is one of the enzymes that can be used in organic synthesis using aromatic compounds (polyphenols and aminofenol) as substrates. Polyphenol compound in green tea is flavan-3-ols or catechin which are susceptible to enzymatic reaction with laccase. In this research laccase isolated from white oyster mushroom was added into the green tea extract. Addition of laccase is expected to yield products with a higher antioxidant activity. Prior to it’s use, laccase activity was determined and h...

  8. Flavan 3-ols improve metabolic syndrome risk factors: evidence and mechanisms

    OpenAIRE

    Osakabe, Naomi

    2013-01-01

    Flavan 3-ols, a type of polyphenolic substance, are distributed in a number of plant foods. Of these foods, chocolate is very rich in flavan 3-ols as flavan 3-ol monomers, (+)-catechin and (−)-epicatechin, and the oligomers as procyanidins. There is evidence that cacao products containing flavan 3-ols have the potential to contribute to the risk reduction of cardiometabolic disorders according to recent epidemiological or intervention studies. This review focuses on recent advances in researc...

  9. Optimization of ultrasound-assisted extraction of flavonoid compounds and their pharmaceutical activity from curry leaf (Murraya koenigii L.) using response surface methodology

    OpenAIRE

    Ghasemzadeh, Ali; Jaafar, Hawa ZE; Karimi, Ehsan; Rahmat, Asmah

    2014-01-01

    Background Extraction prior to component analysis is the primary step in the recovery and isolation of bioactive phytochemicals from plant materials. Methods Response surface methodology was applied to optimize ultrasound-assisted extraction conditions followed by ultra high performance liquid chromatography (UHPLC) to achieve high catechin, myricetin, and quercetin contents, and high antioxidant and anticancer activities in the curry leaf extracts. The antioxidant and anticancer activities o...

  10. Ultrasound-Assisted Extraction of Antioxidants in Misai Kucing (Orthosiphon stamineus)

    OpenAIRE

    Swee Kheng Ho; Chin Ping Tan; Yin Yin Thoo; Faridah Abas; Chun Wai Ho

    2014-01-01

    Ultrasound-assisted extraction (UAE) with ethanol was used to extract the compounds responsible for the antioxidant activities of Misai Kucing (Orthosiphon stamineus). Response surface methodology (RSM) was used to optimize four independent variables: ethanol concentration (%), amplitude (%), duty cycle (W/s) and extraction time (min). Antioxidant compounds were determined by total phenolic content and total flavonoid content to be 1.4 g gallic acid equivalent/100 g DW and 45 g catechin equiv...

  11. (−)-Epigallocatechin Gallate, A Major Constituent of Green Tea, Poisons Human Type II Topoisomerases†

    OpenAIRE

    Bandele, Omari J.; Osheroff, Neil

    2008-01-01

    (−)-Epigallocatechin gallate (EGCG) is the most abundant and biologically active polyphenol in green tea, and many of the therapeutic benefits of the beverage have been attributed to this compound. High concentrations of EGCG are cytotoxic and trigger genotoxic events in mammalian cells. Although this catechin affects a number of cellular systems, the genotoxic effects of several bioflavonoid-based dietary polyphenols are believed to be mediated, at least in part, by their actions on topoisom...

  12. Flavonoids from the Red Alga Acanthophora spicifera

    Institute of Scientific and Technical Information of China (English)

    ZENG Long-Mei(曾陇梅); 曾陇梅; WANG Chao-Jie(王超杰); 王超杰; SU Jing-Yu(苏镜娱); 苏镜娱; LI Du(李笃); 李笃; OWEN Noel L.; OWEN Noel L; LU Yang(吕扬); 吕扬; LU Nan(鲁南); 鲁南; ZHENG Qi-Tai(郑启泰); 郑启泰

    2001-01-01

    Two new flavonoids, acanthophorin A (1) and acanthophorin B (2), along with three known compounds tiliroside (3),( - )-catechin (4) and quercetin (5) were isolated from the red alga Acanthophora spicifera. The structures of 1 and 2were determined to be kaempferol 3-O-α-L-fucopyranoside (1) and quercetin 3-O-α-L-fucopyranoside (2) by spectroscopic methods. Both 1 and 2 showed significant anfioxidant activity.

  13. Phenolic Compounds of Pinus brutia Ten.: Chemical Investigation and Quantitative Analysis Using an Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry with Electrospray Ionization Source

    OpenAIRE

    İbrahim Kıvrak; Şeyda Kıvrak; Mansur Harmandar; Yunus Çetintaş

    2013-01-01

    In this study, phenolic content of Pinus brutia ’s bark was examined using an ultra-performance liquid chromatography tandem mass spectrometry with electrospray ionization source (UPLC-ESI-MS/MS) working in multiple reaction monitoring mode. U ltrasonic extraction method with 50% ethanol solution was used for the extraction of bark. The bark of Pinus brutia consisted of 15 compounds: gallic acid, gentisic acid, protocatechuic acid, 4-hydroxy benzoic acid, catechin hydrate, vanillic acid, caff...

  14. Natural products and body weight control

    OpenAIRE

    Jay Lee; Yanmei Li; Chunhua Li; Duo Li

    2011-01-01

    The purpose of the review was to summarise the effect of some commonly available natural products used for body weight management. We collected data from PubMed and scientific journals. There are numerous publications on this topic, however we have summarized the most commonly available and potent natural products from recent 53 publications. The natural products analyzed in this paper include catechins, capsaicin, conjugated linoleic acid, fucoxanthin, soy isoflavone, glabridin, astaxanthin ...

  15. 加熱処理が果実のポリフェノール化合物に与える影響

    OpenAIRE

    平井, 俊次; 千, 裕美; 近藤, 民恵; 川俣, 幸一

    2006-01-01

    Fruits intakes have been widely recommended in the maintenance and improvement of health in the practice of dietary habits. Many fruits contain large amounts of polyphenol like tannin (catechin), flavonoid and anthocyan. All are rich in anti-oxidants. We unfortunately, do not currently possess adequate information with regards to polyphenol levels in domestic Japanese fruits and their response to environmental stresses such as heat treatment, which is very inconvenient from the our utilizing ...

  16. A fast method using a new hydrophilic–lipophilic balanced sorbent in combination with ultra-high performance liquid chromatography for quantification of significant bioactive metabolites in wines

    OpenAIRE

    Silva, Catarina L.; Pereira, Jorge; Wouter, Van G.; Giró, Carme; Câmara, José S.

    2011-01-01

    This manuscript describes the development and validation of an ultra-fast, efficient, and high throughput analytical method based on ultra-high performance liquid chromatography (UHPLC) equipped with a photodiode array (PDA) detection system, for the simultaneous analysis of fifteen bioactive metabolites: gallic acid, protocatechuic acid, (−)-catechin, gentisic acid, (−)-epicatechin, syringic acid, p-coumaric acid, ferulic acid, m-coumaric acid, rutin, trans-resveratrol, myricetin, quercetin,...

  17. Phenolic Profile of Asturian (Spain) Natural Cider

    OpenAIRE

    Rodríguez, Roberto; Picinelli, A.M. (Anna); Suárez, Belén

    2011-01-01

    The polyphenolic composition of natural ciders from the Asturian community (Spain), during 2 consecutive years, was analyzed by RP-HPLC and the photodiode-array detection system, without previous extraction (direct injection). A total of 16 phenolic compounds (catechol, tyrosol, protocatechuic acid, hydrocaffeic acid, chlorogenic acid, hydrocoumaric acid, ferulic acid, (-)-epicatechin, (+)-catechin, procyanidins B2 and B5, phloretin-2¢-xyloglucoside, phloridzin, hyperin, aviculari...

  18. Effect of Protectants on the Fermentation Performance of Wine Yeasts Subjected to Osmotic Stress

    OpenAIRE

    CARIDI, Andrea

    2003-01-01

    During alcoholic fermentation of must from dried grapes, yeasts are subjected to very high sugar concentrations, besides other environmental stresses, and they modify their metabolic behaviour giving low ethanol yield and abnormally high acetic acid production. To investigate the protective effect of catechin, inositol, and SO2 on wine yeasts, three thermotolerant strains of Saccharomyces cerevisiae, selected for wine making of must from dried grapes, and three strains of Saccharomyces select...

  19. Inhibition of Adipogenesis by Oligonol through Akt-mTOR Inhibition in 3T3-L1 Adipocytes

    OpenAIRE

    Jae-Yeo Park; Younghwa Kim; Jee Ae Im; Seungkwon You; Hyangkyu Lee

    2014-01-01

    Polyphenols have recently become an important focus of study in obesity research. Oligonol is an oligomerized polyphenol, typically comprised of catechin-type polyphenols from a variety of fruits, which has been found to exhibit better bioavailability and bioreactivity than natural polyphenol compounds. Here, we demonstrated that Oligonol inhibits 3T3-L1 adipocyte differentiation by reducing adipogenic gene expression. During adipogenesis, Oligonol downregulated the mRNA levels of peroxisome ...

  20. Novel insights of dietary polyphenols and obesity

    OpenAIRE

    Wang, Shu; Moustaid-Moussa, Naima; Chen, Lixia; Mo, Huanbiao; Shastri, Anuradha; Su, Rui; Bapat, Priyanka; Kwun, InSook; Shen, Chwan-Li

    2014-01-01

    Prevalence of obesity has steadily increased over the past three decades both in the United States and worldwide. Recent studies have shown the role of dietary polyphenols in the prevention of obesity and obesity-related chronic diseases. Here we evaluated the impact of commonly consumed polyphenols, including green tea catechins and epigallocatechin gallates, resveratrol, and curcumin, on obesity and obesity-related-inflammation. Cellular studies demonstrated that these dietary polyphenols r...

  1. Separation and Identification of Flavonoids from Fistular Onion Stalk(Allium fisturosum L.var.Caespitosum Makio)

    Institute of Scientific and Technical Information of China (English)

    付琴琴; 刘静幽; 张长弓; 周银波; 张耕; 马丹; 杨新洲

    2010-01-01

    The chemical constituents of fistular onion stalk obtained by supercritical CO2 extraction were separated and purified by silica gel and sephadex LH-20 gel column chromatography and the preparative TLC method and four flavonoids were obtained.On the basis of the spectral data,they were structurally identified as(+)-catechin,(-)-epicatechin,astragalin,and 3-O-β-D(2-O-β-D-glucopyranosyl)-glucopyranosides of kaempferol.

  2. Whitening efficacy of plant extracts including Hippophae rhamnoides and Cassia fistula extracts on the skin of Asian patients with melasma

    OpenAIRE

    Khan, Barkat Ali; Akhtar, Naveed; Irshad HUSSAIN; Abbas, Khwaja Asad; Rasul, Akhtar

    2013-01-01

    Introduction Melasma/hyperpigmentation and solar damage of the skin remains a difficult problem to treat. Various types of whitening agents are used to treat hyperpigmentation. A change has been observed recently to use plant extracts as skin whitening agents. Aim To compare the effectiveness of emulsion formulations containing plant extracts that include catechins/polyphenols and placebo without plant extracts, on patients with melasma. Material and methods Two groups of 25 patients each (ag...

  3. Yizhijiannao Granule and a combination of its effective monomers, icariin and Panax notoginseng saponins, inhibit early PC12 cell apoptosis induced by beta-amyloid (25–35)☆

    OpenAIRE

    Zhang, Ting; Zhang, Zhanwei; Dong, Keli; Li, Guangcheng; Zhu, Hong

    2012-01-01

    One of our previous studies showed that Yizhijiannao Granule, a compound Chinese medicine, effectively improved the clinical symptoms of Alzheimer's disease. In the present study, we established a model of Alzheimer's disease using beta-amyloid (25–35) in PC12 cells, and treated the cells with Yizhijiannao Granule and its four monomers, i.e., icariin, catechin, Panax notoginseng saponins, and eleutheroside E. Flow cytometry showed that Yizhijiannao Granule-containing serum, icariin, Panax not...

  4. Phenolic Constituents, Antioxidant and Preliminary Antimycoplasmic Activities of Leaf Skin and Flowers of Aloe vera (L.) Burm. f. (syn. A. barbadensis Mill.) from the Canary Islands (Spain)

    OpenAIRE

    Milagros Rico; Ramírez, Ana S; Orestes Vega-Orellana; Miguel Suárez de Tangil; Aroa López

    2013-01-01

    The methanol extracts of leaf skins and flowers of Aloe vera from the Canary Islands were analyzed for their phenolic profiles and screened for their antioxidant and antimycoplasmic activities. The use of reversed phase high performance liquid chromatography (RP-HPLC) allowed the identification of 18 phenolic constituents. Leaf skin extracts were characterized by the abundance of catechin, sinapic acid and quercitrin. Gentisic acid, epicatechin and quercitrin were the most prominent phenolic ...

  5. Identification and antioxidant activity of several flavonoids of inga edulis leaves

    OpenAIRE

    Souza, Jesus N. S.; Silva, Evaldo M.; Milton N. da Silva; Arruda, Mara S. R.; Larondelle, Yvan; Rogez, Herve

    2007-01-01

    A methanol-water extract of Inga edulis leaves was fractionated to identify the polyphenolic compounds. The identified compounds were gallic acid, catechin, epicatechin, myricetin-3rhamnopyranoside, quercetin-3-glucopyranoside and quercetin-3-rhamnopyranoside. The antioxidant activity of the extract and of pure polyphenols was measured by the ORAC assay and compared with the Total Phenolic (TP) content. The dry crude extract presented very high values for ORAC (11.16 mmol TE per g) and TP (49...

  6. Formulasi dan Uji Efek Anti-Aging dari Krim Mengandung Ekstrak Kulit Buah Delima (Punica granatum L)

    OpenAIRE

    Ramadhilla, Nailul

    2015-01-01

    Anti-aging is a process that useful to prevent or slow down the effects of aging. Pomegranate peel is rich with flavonoids, phenolic acids, catechins and tannins which are using as an antioxidant. The objective of this study is to prepare an anti-aging cream using pomegranate peel extract and determine how long its to provide an anti-aging effects. This study was carried out experimentally. Pomegranate peel extracted by maceration using ethanol 70% and concentrated by using rotary evaporat...

  7. Supplementation with a polyphenolic blend improves post-exercise strength recovery and muscle soreness

    OpenAIRE

    Kelli A. Herrlinger; Chirouzes, Diana M.; Ceddia, Michael A.

    2015-01-01

    Background: Exercise can initiate a cascade of inflammatory and oxidative stress–related events leading to delayed onset muscle soreness. Polyphenols possess antioxidant and anti-inflammatory properties.Objective: The current study examined the effects of a proprietary polyphenolic blend (PB), containing catechins and theaflavins, on exercise performance and recovery following an eccentric exercise challenge.Design: Male participants (18–35 years of age) received placebo or PB at a low dose (...

  8. Effect of Green Tea Extract in Reducing Genotoxic Injuries of Cell Phone Microwaves on Bone Marrow

    OpenAIRE

    Zahra Zahedifar; Javad Baharara

    2013-01-01

    Background: Green tea (Camellia sinensis) extract is rich source of natural antioxidants specially catechin that is quickly absorbed into the body and it has cancer protective, anti microbial and anti inflammation effects. In this study has been studied role of green tea extract against genotoxic damage induced by cell phone microwaves on bone marrow polychromatic erythrocytes of adult male Balb/C mouse.Materials and Methods: In this experimental study 40 mouse were divided into five groups, ...

  9. Phenolic profile and antioxidant properties of commercial and wild Fragaria vesca L. roots: A comparison between hydromethanolic and aqueous extracts

    OpenAIRE

    Dias, Maria Inês; Barros, Lillian; Oliveira, M. Beatriz P.P.; Santos-Buelga, Celestino; Ferreira, Isabel C. F. R.

    2015-01-01

    The phenolic profile of hydromethanolic extracts, infusions and decoctions of commercial and wild samples of Fragaria vesca (wild strawberry) roots was obtained by HPLC-DAD/ESI-MS, and further correlated with their antioxidant properties. Commercial and wild samples showed similarities in terms of flavan-3-ols (TF3O), with catechin derivatives, mainly procyanidins, as major compounds in both samples. The commercial sample presented ellagic acid glycosides, whereas the wild sample presented fl...

  10. Comparative evaluation of different co-antioxidants on the photochemical- and functional-stability of epigallocatechin-3-gallate in topical creams exposed to simulated sunlight.

    Science.gov (United States)

    Scalia, Santo; Marchetti, Nicola; Bianchi, Anna

    2013-01-01

    The catechin (-)-epigallocatechin-3-gallate (EGCG) exhibits high antioxidant activity and it has been reported to provide protection of the skin against damage induced by solar UV radiation. However, EGCG is highly unstable under sunlight. The present study aimed to compare the effectiveness of the co-antioxidant agents vitamin E, butylated hydroxytoluene, vitamin C and a-lipoic acid for their potential to protect the catechin from photochemical degradation. Model creams (oil-in-water emulsions) containing EGCG (1%, w/w) alone or combined with equimolar concentrations of co-antioxidant were exposed to a solar simulator at an irradiance corresponding to natural sunlight. Photodegradation was evaluated by HPLC-UV and HPLC-ESI-MS/MS. Addition of the co-antioxidants vitamin C and a-lipoic acid to the formulation significantly reduced the light-induced decomposition of EGCG from 76.9 ± 4.6% to 20.4 ± 2.7% and 12.6 ± 1.6%, respectively. Conversely, butylated hydroxytoluene had no effect (EGCG loss, 78.1 ± 4.6%) and vitamin E enhanced the EGCG photolysis to 84.5 ± 3.4%. The functional stability of the catechin in the creams exposed to the solar simulator was also evaluated by measuring the in vitro antioxidant activity. Following irradiation, the reduction of the EGCG formulation antioxidant power was lower (21.8%) than the extent of degradation (76.9%), suggesting the formation of photoproducts with antioxidant properties. The influence of the examined co-antioxidants on the functional stability of the catechin under simulated sunlight paralleled that measured for the EGCG photodecomposition, a-lipoic acid exerting the greatest stabilising effect (antioxidant activity decrease, 1.4%). These results demonstrated that a-lipoic acid is an effective co-antioxidant agent for the stabilization of EGCG in dermatological products for skin photoprotection. PMID:23292326

  11. Synthesis of Phenolics and Flavonoids in Ginger (Zingiber officinale Roscoe) and Their Effects on Photosynthesis Rate

    OpenAIRE

    Asmah Rahmat; Jaafar, Hawa Z. E.; Ali Ghasemzadeh

    2010-01-01

    The relationship between phenolics and flavonoids synthesis/accumulation and photosynthesis rate was investigated for two Malaysian ginger (Zingiber officinale) varieties grown under four levels of glasshouse light intensity, namely 310, 460, 630 and 790 μmol m−2s−1. High performance liquid chromatography (HPLC) was employed to identify and quantify the polyphenolic components. The results of HPLC analysis indicated that synthesis and partitioning of quercetin, rutin, catechin, epicatechin an...

  12. Antiplatelet activity of Croton celditifolius Atividade antiplaquetária do Croton celtidifolius

    OpenAIRE

    Teresinha de Jesus Carvalho Neiva; Ana Carolina Rabello de Moraes; Carlos Buchele; Moacir Geraldo Pizzolatti; Elbio Antônio D'Amico; Diana Marli Fries; Tania Rubia Flores da Rocha

    2008-01-01

    Croton celtidifolius Baill is a tree found in the Atlantic Forest South of Brazil, mainly in Santa Catarina. The bark and leaf infusions of this medicinal plant have been popularly used for the treatment of inflammatory diseases. The anti-aggregant activity of C. celtidifolius crude extract (CE) and the column chromatography (CC) isolated compounds flavonoids, catechin and gallocatechin were evaluated in human blood platelets. The platelet-rich plasma (PRP) was incubated with different concen...

  13. The effect of water plant extracts addition on the oxidative stability of meat products

    OpenAIRE

    Karolina M. Wójciak; Zbigniew J.Dolatowski; Anna Okoń

    2011-01-01

    Background. Natural antioxidants extracted from plants have a lot of antioxidants catechins, epigallocatechins (green tea) rosmariquinone, rosmaridiphenol (rosemary), capsaicinoids (red pepper). They can be used as alternatives to the synthetic antioxidants because of their equivalence or greater effect on inhibition of lipid oxidation and haem pigment (nitrosohemachrome) protection. The aim of the study was to compare the effect of addition of green tea extract, red pepper extract and ...

  14. The effect of antioxidants on Lactobacillus casei cultures

    OpenAIRE

    Aleksandra Duda-Chodak; Tomasz Tarko; Mateusz Statek

    2008-01-01

    The growing popularity of functional foods causes increasing interest in raw materials, which can raise the pro-health value of food when supplemented. The aim of the study was to assess the effect of compounds with antioxidant properties on Lactobacillus casei, as a representative of probiotic microorganisms. In the experiments the pure antioxidants and plant extracts were used. The results showed that catechin at concentration of 100-400 M and chlorogenic acid (400 M...

  15. Antiherpetic activity of a flavonoid fraction from Ocotea notata leaves

    OpenAIRE

    Rafael Garrett; Maria Teresa V. Romanos; Ricardo M. Borges; MARCELO G. SANTOS; Leandro Rocha; Antonio Jorge R. da Silva

    2012-01-01

    This study describes the isolation of a flavonoid fraction from leaves of Ocotea notata (Nees & Mart.) Mez, Lauraceae, the identification of six major compounds (an A-type proanthocyanidin trimer [3], isoquercitrin [4], reynoutrin [5], miquelianin [6], quercitrin [7], afzelin [8]) and four minor compounds (catechin [1], epicatechin [2], quercetin [9], kaempferol [10]) present in the fraction and its activity against the Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2). The 50% effective...

  16. Prevention of thermal degradation of red currant juice anthocyanins by phenolic compounds addition

    OpenAIRE

    Kopjar, Mirela; Piližota, Vlasta; Šubarić, D.; Babić, J.

    2009-01-01

    The aim of this study was investigation of prevention of thermal degradation of the red currant juice anthocyanins by addition of different phenolic compounds (catechol, 4-methyl catechol, catechin, chlorogenic acid and gallic acid). Phenolic compounds were added in 50:1 and 100:1 copigment:pigment molar ratio. Red currant juice samples were heated at 30, 50, 70 and 90 °C for 1 hour. Thermal degradation of anthocyanins was investigated through determination of anthocyanin content and calculat...

  17. Properties of Chitosan-Genipin Films Grafted with Phenolic Compounds from Red Wine

    OpenAIRE

    Gonçalves, Fernando Jorge

    2015-01-01

    Chitosan has been studied as a renewable biopolymer to form edible films and coatings to improve the shelf life of food products. Chemical modification of chitosan is a strategy to prepare chitosan films with enhanced properties to be used as food preservatives. Wine, particularly red wine, is a rich natural source of phenolic compounds, namely anthocyanins, proanthocyanidins, monomeric catechins, and phenolic acids. Phenolic compounds, in general, present strong antioxidant properties. The a...

  18. Radiation induced chemical changes of phenolic compounds in strawberries

    International Nuclear Information System (INIS)

    In unirradiated strawberries four phenolic acids (gallic acid, p-coumaric acid, caffeic acid and 4-hydroxybenzoic acid), the flavonoids (+)-catechin, (-)-epicatechin and glycosides from kaempferol and quercetin were determined by reversed phase chromatography with diode array detection. Characteristic linear dose/concentration relationships were found for 4-hydroxybenzoic acid and two unidentified compounds. One of them may be usable as marker to prove an irradiation treatment

  19. Adsorption capacity of phenolic compounds onto cellulose and xylan

    OpenAIRE

    Telma dos Santos Costa; Hervé Rogez; Rosinelson da Silva Pena

    2015-01-01

    The interaction between three phenolic compounds (catechin, caffeic acid and ferulic acid) onto two dietary fibres (cellulose and xylan) has been evaluated to inquire possible interferences on the biodisponibility of phenolic compounds. The adsorption kinetics were performed using solutions containing 100 mg/L of phenolic compounds during a contact time ranging between 10 and 120 minutes at pH 2.0, 4.5, and 7.0. After the kinetics, isotherms were obtained using phenolic compounds concentratio...

  20. Secondary Metabolite Content in Roots and Callus of Paeonia Anomala L.

    OpenAIRE

    A.A. ZARIPOVA

    2014-01-01

    Taking into account the fact that in the process of introduction in vitro culture the change of secondary metabolite content may take place we compared the chemical composition of plant material of wild-growing plants of Paeonia anomala introduced and produced using the methods of clonal micropropagation, callus tissue.The content of phenolic compounds, that is catechins and gallatos was compared. Paeoniflorin content was estimated by direct spectrophotometry of methanol extracts (λ = 231,7 n...

  1. Dietary flavonoid intake and thyroid cancer risk in the NIH-AARP Diet and Health Study

    OpenAIRE

    Xiao, Qian; Park, Yikyung; Hollenbeck, Albert R.; Kitahara, Cari M.

    2014-01-01

    Experimental studies suggested that flavonoids may influence thyroid carcinogenesis, but epidemiological evidence is sparse. No study has examined different classes of flavonoids in relation to thyroid cancer risk. Using data from the NIH-AARP Diet and Health Study, which enrolled 491,840 U.S. men and women, ages 50 to 71 at baseline, we prospectively examined the risk of thyroid cancer in relation to dietary intakes of catechins, flavanones, flavonols, anthocyanidins, flavones, isoflavones, ...

  2. Local Controlled Release of Polyphenol Conjugated with Gelatin Facilitates Bone Formation

    OpenAIRE

    Yoshitomo Honda; Tomonari Tanaka; Tomoko Tokuda; Takahiro Kashiwagi; Koji Kaida; Ayato Hieda; Yasuyuki Umezaki; Yoshiya Hashimoto; Koichi Imai; Naoyuki Matsumoto; Shunsuke Baba; Kimishige Shimizutani

    2015-01-01

    Catechins are extensively used in health care treatments. Nevertheless, there is scarce information about the feasibility of local administration with polyphenols for bone regeneration therapy, possibly due to lack of effective delivery systems. Here we demonstrated that the epigallocatechin-3-gallate-conjugated gelatin (EGCG/Gel) prepared by an aqueous chemical synthesis using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-morpholinium chloride (DMT-MM) gradually disintegrated with time and facilita...

  3. Enriquecimento de compostos fenólicos de folhas de Inga edulis por extração em fase sólida: quantificação de seus compostos majoritários e avaliação da capacidade antioxidante Purification of phenolic compounds from Inga edulis leaves using solid-phase extraction: major compounds quantification and antioxidant capacity evaluation

    OpenAIRE

    Aécio Luís de Sousa Dias; Jesus Nazareno Silva Souza; Hervé Rogez

    2010-01-01

    A phenolic fraction was obtained from of the acetone-water-acetic acid extract of Inga edulis leaves, by liquid-liquid partition and SPE-C18 cartridges. This method provided an increase of 108, 66, 51, 50 and 36% of flavonols, proanthocyanidins, total polyphenols, gallotannins and flavanols, respectively. The major phenolics in purified fraction were procyanidin B2, catechin and myricetin-3-O-α-L-rhamnopyranoside, which achieved increases of 111, 47 and 45%, respectively, after SPE. Acid...

  4. Green tea inhibited the elimination of nephro-cardiovascular toxins and deteriorated the renal function in rats with renal failure

    OpenAIRE

    Yu-Hsuan Peng; Sweet, Douglas H.; Shiuan-Pey Lin; Chung-Ping Yu; Pei-Dawn Lee Chao; Yu-Chi Hou

    2015-01-01

    Chronic kidney disease (CKD) is a major health problem worldwide. Indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are highly protein-bound nephro-cardiovascular toxins, which are not efficiently removed through hemodialysis. The renal excretions of IS and PCS were mediated by organic anion transporters (OATs) such as OAT1 and OAT3. Green tea (GT) is a popular beverage containing plenty of catechins. Previous pharmacokinetic studies of teas have shown that the major molecules present in the bl...

  5. Green Tea Polyphenols Function as Prooxidants To Activate Oxidative-Stress-Responsive Transcription Factors in Yeasts▿

    OpenAIRE

    Maeta, Kazuhiro; Nomura, Wataru; Takatsume, Yoshifumi; Izawa, Shingo; Inoue, Yoshiharu

    2006-01-01

    Epigallocatechin gallate (EGCG) is the most abundant polyphenolic flavonoid in green tea. Catechin and its derivatives, including EGCG, are widely believed to function as antioxidants. Here we demonstrate that both EGCG and green tea extract (GTE) cause oxidative stress-related responses in the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe under weak alkaline conditions in terms of the activation of oxidative-stress-responsive transcription factors. GT...

  6. Food Ingredients as Anti-Obesity Agents.

    Science.gov (United States)

    Saito, Masayuki; Yoneshiro, Takeshi; Matsushita, Mami

    2015-11-01

    Brown adipose tissue (BAT) is a site of adaptive non-shivering thermogenesis after cold exposure, and is involved in the regulation of energy expenditure and body fatness. BAT can be activated and recruited by not only cold exposure but also by various food ingredients including capsaicin in chili pepper and catechins in green tea, which would be easily and safely applicable to our daily life for preventing obesity. PMID:26421678

  7. Phenolic compounds of green tea: Health benefits and technological application in food

    OpenAIRE

    José Manuel Lorenzo; Paulo Eduardo Sichetti Munekata

    2016-01-01

    Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodeg...

  8. Original article phenolic composition of European cranberry bush (viburnum opulus l.) Berries and astringency removal of its commercial juice

    OpenAIRE

    EKİCİ, Lütfiye; Poyrazoğlu, Ender Sinan

    2005-01-01

    Phenolic composition of the European cranberrybush (ECB) (Viburnum opulus L.) juice was determinedusing high-performance liquid chromatography. The juice contained 2037 mg kg)1 chlorogenic acid, whichwas 54% of total phenolics, and several other phenolics such as (+)-catechin, ())-epicatechin, cyanidin-3-glucoside, cyanidin-3-rutinoside and six different glucosides of quercetin. Because of its strong astringenttaste, the juices were treated with various doses of two different types of activat...

  9. Characterization of polyphenoloxidase (PPO) extracted from "Jonagored" apple

    OpenAIRE

    Rocha, A. M. C. N.; Morais, A. M. M. B.

    2001-01-01

    Polyphenoloxidase (PPO) was extracted from apple (cv. Jonagored) with addition of 2% PVP and 0.25% Triton X100 to the extraction buffer containing phenolic adsorbents. Experiments were performed to evaluate the affinity and specificity towards several substrates. ‘Jonagored’ apple PPO was found to have higher specificity (lower Km) towards L-dopa, 4-methylcatechol and (+) catechin than other phenols tested, but the highest activity level was obtained with p-cresol. The ratio Vmax/Km indicates...

  10. Cocoa and Chocolate in Human Health and Disease

    OpenAIRE

    Katz, David L.; Doughty, Kim; Ali, Ather

    2011-01-01

    Cocoa contains more phenolic antioxidants than most foods. Flavonoids, including catechin, epicatechin, and procyanidins predominate in antioxidant activity. The tricyclic structure of the flavonoids determines antioxidant effects that scavenge reactive oxygen species, chelate Fe2+ and Cu+, inhibit enzymes, and upregulate antioxidant defenses. The epicatechin content of cocoa is primarily responsible for its favorable impact on vascular endothelium via its effect on both acute and chronic upr...

  11. Prooxidative Potential of Photo-Irradiated Aqueous Extracts of Grape Pomace, a Recyclable Resource from Winemaking Process

    Science.gov (United States)

    Nakashima, Takuji; Kamachi, Toshiaki

    2016-01-01

    Our previous study revealed that aqueous extract of grape pomace obtained from a winemaking process could exert bactericidal action upon photo-irradiation via reactive oxygen species (ROS) formation. In the present study, we focused on chemical composition and prooxidative profile of the extract. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) analysis showed that polyphenolic compounds including catechin monomers, dimers, trimers, and polyphenolic glucosides were contained. The polyphenol rich fraction used for the LC-ESI-MS analysis generated hydrogen peroxide (H2O2) upon photo-irradiation possibly initiated by photo-oxidation of phenolic hydroxyl group. That is, reduction of dissolved oxygen by proton-coupled electron transferred from the photo-oxidized phenolic hydroxyl group would form H2O2. The resultant H2O2 was then photolyzed to generate hydroxyl radical (•OH). The prooxidative profile of the extract in terms of •OH generation pattern upon photo-irradiation was similar to that of grape seed extract (GSE) as an authentic polyphenol product and (+)-catechin as a pure polyphenolic compound, and in all the three samples •OH generation could be retained during photo-irradiation for at least a couple of hours. The prooxidant activity of the photo-irradiated extract indicated by •OH yield was more potent than that of the photo-irradiated GSE and (+)-catechin, and this was well reflected in their bactericidal activity in which the photo-irradiated extract could kill the bacteria more efficiently than did the photo-irradiated GSE and (+)-catechin. PMID:27341398

  12. Comparative Evaluation of Different Co-Antioxidants on the Photochemical- and Functional-Stability of Epigallocatechin-3-gallate in Topical Creams Exposed to Simulated Sunlight

    Directory of Open Access Journals (Sweden)

    Santo Scalia

    2013-01-01

    Full Text Available The catechin (−-epigallocatechin-3-gallate (EGCG exhibits high antioxidant activity and it has been reported to provide protection of the skin against damage induced by solar UV radiation. However, EGCG is highly unstable under sunlight. The present study aimed to compare the effectiveness of the co-antioxidant agents vitamin E, butylated hydroxytoluene, vitamin C and a-lipoic acid for their potential to protect the catechin from photochemical degradation. Model creams (oil-in-water emulsions containing EGCG (1%, w/w alone or combined with equimolar concentrations of co-antioxidant were exposed to a solar simulator at an irradiance corresponding to natural sunlight. Photodegradation was evaluated by HPLC-UV and HPLC-ESI-MS/MS. Addition of the co-antioxidants vitamin C and a-lipoic acid to the formulation significantly reduced the light-induced decomposition of EGCG from 76.9 ± 4.6% to 20.4 ± 2.7% and 12.6 ± 1.6%, respectively. Conversely, butylated hydroxytoluene had no effect (EGCG loss, 78.1 ± 4.6% and vitamin E enhanced the EGCG photolysis to 84.5 ± 3.4%. The functional stability of the catechin in the creams exposed to the solar simulator was also evaluated by measuring the in vitro antioxidant activity. Following irradiation, the reduction of the EGCG formulation antioxidant power was lower (21.8% than the extent of degradation (76.9%, suggesting the formation of photoproducts with antioxidant properties. The influence of the examined co-antioxidants on the functional stability of the catechin under simulated sunlight paralleled that measured for the EGCG photodecomposition, a-lipoic acid exerting the greatest stabilising effect (antioxidant activity decrease, 1.4%. These results demonstrated that a-lipoic acid is an effective co-antioxidant agent for the stabilization of EGCG in dermatological products for skin photoprotection.

  13. The synergistic apoptotic interaction of panaxadiol and epigallocatechin gallate in human colorectal cancer cells

    OpenAIRE

    Du, Guang-Jian; Wang, Chong-Zhi; Qi, Lian-Wen; Zhang, Zhi-Yu; Calway, Tyler; He, Tong-Chuan; Du, Wei; Yuan, Chun-Su

    2012-01-01

    Panaxadiol (PD) is a purified sapogenin of ginseng saponins, which exhibits anticancer activity. Epigallocatechin gallate (EGCG), a major catechin in green tea, is a strong botanical antioxidant. In this study, we investigated the possible synergistic anticancer effects of PD and EGCG on human colorectal cancer cells and explored the potential role of apoptosis in the synergistic activities. Effects of selected compounds on HCT-116 and SW-480 human colorectal cancer cells were evaluated by an...

  14. Comparison of methods for determination of polyphenols in wine by HPLC-UV/VIS, LC/MS/MS and spectrophotometry

    OpenAIRE

    Kočar, Drago; Weingerl, Vesna; Strlič, Matija

    2015-01-01

    Phenolic antioxidants are usually grouped into flavonoids and non-flavonoids, according to their structure. With regard to the tannic character, phenolic antioxidants are further subdivided to tannic phenols and non-tannic phenols. Collectively, these compounds contribute to the high antioxidant capacity of wine.In this work, we compare determination of gallic acid, catechin, epicatechin, resveratrol, quercetin, dihydrobenzoic acid, sinapic acid, vanillic acid, caffeic acid, chlorogenic acid,...

  15. The Joint Use of Electronic Nose and Electronic Tongue for the Evaluation of the Sensorial Properties of Green and Black Tea Infusions as Related to Their Chemical Composition

    OpenAIRE

    Susanna Buratti; Antonella Casiraghi; Paola Minghetti; Gabriella Giovanelli

    2013-01-01

    The objectives of the present study were to determine the effects of the brewing method on the amount of the major catechins, methylxanthines, total polyphenols and antioxidant capacity in green and black teas, and to correlate the chemical composition of tea infusions to their sensorial properties by the combined use of the electronic nose and tongue. For this purpose, tea infusions were prepared from 7 green teas and 6 black teas using different extraction times (3 - 5 and 10 min). The extr...

  16. Biological Effects of Green Tea Capsule Supplementation in Pre-Surgery Postmenopausal Breast Cancer Patients

    OpenAIRE

    StevenSYu; DarcyVSpicer; DebraHawes; Chiu-ChenTseng; ChungSYang; MalcolmCPike

    2013-01-01

    Regular green tea intake has been associated with an inverse risk of breast cancer. There is compelling experimental evidence that green tea, particularly, epigallocatechin gallate, the most potent green tea catechin, possesses a range of anti-cancer properties. We conducted a pre-surgical study of green tea capsules versus no green tea in women with primary breast cancer to determine the effects of green tea supplementation on markers of biological response. Postmenopausal women with duct...

  17. Role of green tea as an antioxidant in periodontal disease: The Asian paradox

    OpenAIRE

    Nugala, Babitha; Namasi, Ambalavanan; Emmadi, Pamela; Krishna, P. Mohana

    2012-01-01

    Green tea is a popular beverage nowadays and intake of green tea polyphenols has shown preventive effect against cancer and cardiovascular disease in experimental and epidemiologic studies. Several studies have suggested that green tea catechins, such as epigallocatechin gallate, inhibit periodontal pathogens and reduce the destruction of periodontal tissue. This paper aims to review the role of green tea in inflammatory diseases, especially in periodontal diseases.

  18. Green Tea Polyphenols Extend the Lifespan of Male Drosophila melanogaster While Impairing Reproductive Fitness

    OpenAIRE

    Lopez, Terry; Schriner, Samuel E.; Okoro, Michael; Lu, David; Chiang, Beatrice T.; Huey, Jocelyn; Jafari, Mahtab

    2014-01-01

    Green tea is a popular beverage believed to have many health benefits, including a reduction in the risks of heart disease and cancer. Rich in polyphenolic compounds known as catechins, green tea and its components have been shown to increase the lifespan of various animal models, including Drosophila melanogaster. Here, we investigated the gender-specific effects of green tea on the lifespan of fruit flies and observed that green tea extended the lifespan of male flies only. This effect was ...

  19. The antimicrobial possibilities of green tea

    OpenAIRE

    Reygaert, Wanda C

    2014-01-01

    Green tea is a popular drink, especially in Asian countries, although its popularity continues to spread across the globe. The health benefits of green tea, derived from the leaves of the Camellia sinensis plant, have been studied for many years. Fairly recently, researchers have begun to look at the possibility of using green tea in antimicrobial therapy, and the potential prevention of infections. The particular properties of catechins found in the tea have shown promise for having antimicr...

  20. THE EFFECT OF GREEN TEA ON OXIDATIVE DAMAGE AND TUMOUR FORMATION IN LOBUND-WISTAR RATS

    OpenAIRE

    O'Sullivan, Jacintha; Sheridan, Juliette; Mulcahy, Hugh; Tenniswood, Martin; Morrissey, Colm

    2008-01-01

    A number of epidemiological studies suggest that the consumption of green tea reduces the incidence of prostate cancer. Since the major catechins present in green tea are potent anti-oxidants, we hypothesized that genetic and cellular damage induced by oxygen free radicals could be significantly reduced by potent anti-oxidants in green tea, thus reducing the cumulative genetic and cellular damage with age, and slowing or preventing tumour formation.

  1. Phenological changes in the chemical content of wild and greenhouse-grown Hypericum pruinatum: flavonoids

    OpenAIRE

    ÇIRAK*, Cüneyt; Radusiene, Jolita; IVANAUSKAS, Liudas; Jakstas, Valdas; ÇAMAŞ, Necdet

    2014-01-01

    The present study was conducted to determine the phenological changes in the content of main flavonoids, namely amentoflavone, hyperoside, isoquercitrin, quercitrin, quercetin, avicularin, rutin, (+)-catechin, and (-)-epicatechin in different tissues of Hypericum pruinatum, a promising medicinal herb of the Turkish flora. The wild-growing and greenhouse-grown plants were harvested at vegetative, floral budding, full flowering, fresh fruiting, and mature fruiting stages and dissected into stem...

  2. Effect of simulated processing on the antioxidant capacity and in vitro protein digestion of fruit juice-milk beverage model systems.

    Science.gov (United States)

    He, Zhiyong; Yuan, Bo; Zeng, Maomao; Tao, Guanjun; Chen, Jie

    2015-05-15

    The effects of simulated processing (pH adjustment and thermal treatment) on the antioxidant capacity and in vitro protein digestion of fruit juice-milk beverage (FJMB) models consisting of whey protein (WP), and chlorogenic acid (CHA) or catechin (CAT) were investigated. Results indicated that CAT was more susceptible to processing than CHA, and showed a significant (p 0.05) by pasteurization, whereas sterilization initially accelerated WP digestion but did not change its overall digestibility. PMID:25577106

  3. Comparing the antiplaque efficacy of 0.5% Camellia sinensis extract, 0.05% sodium fluoride, and 0.2% chlorhexidine gluconate mouthwash in children

    OpenAIRE

    Hambire, Chaitali U.; Jawade, Rashmi; Patil, Amol; Wani, Vaibhav R.; Kulkarni, Ankur A.; Nehete, Parag B.

    2015-01-01

    Background: Dental caries is a multifactorial disease which requires a susceptible host, a cariogenic microflora, and a suitable substrate that must be present for a sufficient length of time. Tea is prepared by the infusion of dried leaves of the tea plant, Camellia sinensis, which contains bioactive compounds like polyphenols, flavonoids, and catechins that are thought to be responsible for the health benefits that have traditionally been attributed to tea. These compounds have multidimensi...

  4. PRELIMINARY PHYTOCHEMICAL ANALYSIS OF ACTINIOPTERIS RADIATA (SWARTZ) LINK.

    OpenAIRE

    R. Manonmani; S. Catharin Sara

    2013-01-01

    The objective of the present study was to find out the presence of preliminary phytochemicals in six different solvent extracts of Actiniopteris radiata (Swartz) link. by qualitative screening methods. The solvent used for the extraction of leaf and rhizome powder were ethanol, petroleum ether, chloroform, acetone, DMSO and aqueous. The secondary metabolites such as steroids, triterpenoids, reducing sugars, sugars, alkaloids, phenolic compounds, catechins, flavonoids, saponins, tannins, anth...

  5. Stimulation or Inhibition Conflicting evidence for (±)-catechin’s role as a chemical facilitator and disease protecting agent

    OpenAIRE

    Bais, Harsh P.; L. Venkatachalam; Biedrzycki, Meredith L

    2010-01-01

    The occurrence of plant hormesis is a poorly understood phenomenon, wherein low doses of phytotoxins unusually promote growth responses in higher plants. In contrast, negative plant-plant interactions mediated through secreted small molecular weight compounds initiate growth inhibitory responses. Studies related to (±)-catechin mediated allelopathy have transpired both novel information and generated significant controversy. Specifically, studies related to the phytotoxicity responses mediate...

  6. Design, formulation and evaluation of green tea chewing gum

    OpenAIRE

    Abolfazl Aslani; Alireza Ghannadi; Zeinab Khalafi

    2014-01-01

    Background: The main purpose of this study is to design, formulate and evaluate the green tea gums with a suitable taste and quality in order to produce an anti-oxidant chewing gum. Materials and Methods: Fresh green tea leaves obtained from Northern Iran for extraction. Maceration is the extraction method that is used in this study. The contents of caffeine, catechin and flavonoids of the hydro alcoholic extract were measured. Various formulations of the 120 mg green tea extract chewing ...

  7. THE INFLUENCE OF TIME AND TYPE OF SOLVENT ON EFFICIENCY OF THE EXTRACTION OF POLYPHENOLS FROM GREEN TEA AND ANTIOXIDANT PROPERTIES OBTAINED EXTRACTS

    OpenAIRE

    Beata Drużyńska; Agnieszka Stępniewska; Rafał Wołosiak

    2007-01-01

    The aim of the study was to investigate the influence of the type of solvent and time on efficiency of the extraction of polyphenols and antioxidant properties extracts obtained from green tea. Extraction was conducted at room temperature using four solvents: water and 80% ethanol, 80% methanol and 80% acetone (water solutions, v/v) at 15, 30 and 60 minutes. Extracts were analysed for contents of polyphenols and catechins. The antioxidant properties have been determined by two methods: scaven...

  8. Influence of Cocoa Flavanols and Procyanidins on Free Radical-induced Human Erythrocyte Hemolysis

    Directory of Open Access Journals (Sweden)

    Qin Yan Zhu

    2005-01-01

    Full Text Available Cocoa can be a rich source of antioxidants including the flavan-3-ols, epicatechin and catechin, and their oligomers (procyanidins. While these flavonoids have been reported to reduce the rate of free radical-induced erythrocyte hemolysis in experimental animal models, little is known about their effect on human erythrocyte hemolysis. The major objective of this work was to study the effect of a flavonoid-rich cocoa beverage on the resistance of human erythrocytes to oxidative stress. A second objective was to assess the effects of select purified cocoa flavonoids, epicatechin, catechin, the procyanidin Dimer B2 and one of its major metabolites, 3ʹ-O-methyl epicatechin, on free radical-induced erythrocyte hemolysis in vitro. Peripheral blood was obtained from 8 healthy subjects before and 1, 2, 4 and 8 h after consuming a flavonoid-rich cocoa beverage that provided 0.25 g/kg body weight (BW, 0.375 or 0.50 g/kg BW of cocoa. Plasma flavanol and dimer concentrations were determined for each subject. Erythrocyte hemolysis was evaluated using a controlled peroxidation reaction. Epicatechin, catechin, 3ʹ-O-methyl epicatechin and (--epicatechin-(4β > 8epicatechin (Dimer B2 were detected in the plasma within 1 h after the consumption of the beverage. The susceptibility of erythrocytes to hemolysis was reduced significantly following the consumption of the beverages. The duration of the lag time, which reflects the capacity of cells to buffer free radicals, was increased. Consistent with the above, the purified flavonoids, epicatechin, catechin, Dimer B2 and the metabolite 3ʹ-O-methyl epicatechin, exhibited dose-dependent protection against AAPH-induced erythrocyte hemolysis at concentrations ranging from 2.5 to 20 μM. Erythrocytes from subjects consuming flavonoid-rich cocoa show reduced susceptibility to free radical-induced hemolysis (p < 0.05.

  9. Relations between Polyphenols Content and Antioxidative Activity in Vine Grapes and Leaves

    Czech Academy of Sciences Publication Activity Database

    Balík, J.; Kyseláková, M.; Vrchotová, Naděžda; Tříska, Jan; Kumšta, M.; Veverka, J.; Híc, P.; Totušek, J.; Lefnerová, D.

    2008-01-01

    Roč. 26, special (2008), s. 25-35. ISSN 1212-1800. [Quality of Moravian and Czech Wines and their Future. Lednice, 11.09.2008-12.09.2008] R&D Projects: GA ČR(CZ) GA525/06/1757 Institutional research plan: CEZ:AV0Z60870520 Keywords : vine grape s * vine leaves * stems * piceid * resveratrol * caftaric acid * catechin Subject RIV: GM - Food Processing Impact factor: 0.472, year: 2008

  10. EFEK KONSUMSI MINUMAN BUBUK KAKAO (Theobroma cacao L.) BEBAS LEMAK TERHADAP SIFAT ANTIOKSIDATIF LIMFOSIT SUBYEK PEREMPUAN [The Effect of Fat Free Cocoa (Theobroma Cacao L.) Powder Drinks Consumption on Antioxidative Activity of Lymphocyte of Women Subjects

    OpenAIRE

    Erniati; Fransiska R Zakaria2); Bambang Pontjo Priosoeryanto

    2012-01-01

    The health benefits of cocoa both in vivo and in vitro have been reported in many studies. Cocoa is a rich source of flavonoids known to have antioxidant activity, such as catechin, epicatechin and procyanidin. The aim of this research was to evaluate the effect of fat free cocoa powder drink consumption on antioxidative properties and proliferation activities of woman lymphocyte. Healthy woman subjects were divided into cocoa group (n = 9) and control group (n = 9). Cocoa powder drink contai...

  11. Short- and long-term effects of (−)-epicatechin on myocardial ischemia-reperfusion injury

    OpenAIRE

    Yamazaki, Katrina Go; Romero-Perez, Diego; Barraza-Hidalgo, Maraliz; Cruz, Michelle; Rivas, Maria; Cortez-Gomez, Brenda; Ceballos, Guillermo; Villarreal, Francisco

    2008-01-01

    Epidemiological studies have shown a correlation between flavonoid-rich diets and improved cardiovascular prognosis. Cocoa contains large amounts of flavonoids, in particular flavanols (mostly catechins and epicatechins). Flavonoids possess pleiotropic properties that may confer protective effects to tissues during injury. We examined the ability of epicatechin to reduce short-and long-term ischemia-reperfusion (I/R) myocardial injury. Epicatechin (1 mg·kg−1·day−1) pretreatment (Tx) was admin...

  12. Partitioning of selected antioxidants in mayonnaise

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; Schwarz, K.; Stockmann, H.; Meyer, Anne S.; Adler-Nissen, Jens

    1999-01-01

    This study examined partitioning of alpha-, beta-, and gamma- tocopherol and six polar antioxidants (Trolox, ferulic acid, caffeic acid, propyl gallate, gallic acid, and catechin) in mayonnaise. Partitioning of antioxidants between different phases was determined after separation of mayonnaise by...... either (a) centrifugation + ultracentrifugation or (b) centrifugation + dialysis. Antioxidants partitioned in accordance with their chemical structure and polarity: Tocopherols were concentrated in the oil phase (93-96%), while the proportion of polar antioxidants in the oil phase ranged from 0% (gallic...

  13. Green Tea, Phytic Acid, and Inositol in Combination Reduced the Incidence of Azoxymethane-Induced Colon Tumors in Fisher 344 Male Rats

    OpenAIRE

    Khatiwada, Janak; Verghese, Martha; Davis, Shurrita; Williams, Leonard L.

    2011-01-01

    Experimental as well as epidemiologic studies in human populations provide evidence that consumption of phytochemicals reduces the incidence of degenerative diseases. Green tea (GT) catechins are known for their antioxidative potential. Phytic acid (PA) also acts as a natural antioxidant and may have numerous health benefits. This experiment was designed to investigate the inhibitory effects of combinations of 1% and 2% GT, PA, and inositol (I) in reducing the incidence of azoxymethane-induce...

  14. Substrate specifity and inhibitors of polyphenol oxidase in aspect of darkening of fresh and frozen mushrooms (Agaricus bisporus (Lange) Sing.)

    OpenAIRE

    Janusz Czapski

    2013-01-01

    Activity of mushroom polyphenol oxidase (PPO) toward 6 substrates and inhibitory effect of cysteine, 2-mercaptoethanol, benzoic acid and sodium metabisulphite were determined. The o-diphenols which appeared to be the best substrates were: catechin, DOPA (L-3,4-dihydro-xyphenylalanine) and chlorogcnic acid. Affinity of PPO crude preparation substrates to enzyme, expressed as inverse value of Michaelis constant was lower then affinity of catechol. Inhibitory effect depended on specifity of inhi...

  15. Chromatographic Profiles and Identification of New Phenolic Components of Ginkgo biloba Leaves and Selected Products

    OpenAIRE

    Lin, Long-Ze; Chen, Pei; Ozcan, Mustafa; Harnly, James M.

    2008-01-01

    Ginkgo biloba leaves and their extracts are one of the most widely used herbal products and/or dietary supplements in the world. A systematic study of the phenolic compounds is necessary to establish quality parameters. A modified LC-DAD-ESI/MS method was used to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves. The method was used to identify 45 glycosylated flavonols and flavones, 3 flavonol aglycones, catechin, 10 biflavones, a dihydroxybenzoi...

  16. The Relationships Between Biological Activities and Structure of Flavan-3-Ols

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    Ioana Berindan Neagoe

    2011-12-01

    Full Text Available Flavan-3-ols are involved in multiple metabolic pathways that induce inhibition of cell proliferation. We studied the structure-activity relationship of gallic acid (GA and four flavan-3-ols: epigallocatechin gallate (EGCG, epigallocatechin (EGC, catechin (C, and epicatechin (EC. We measured the cell viability by the MTT assay and we determined the concentration of testing compound required to reduce cell viability by 50% (IC50. All tested compounds showed a dose-dependent and time-dependent inhibitory antiproliferative effect on Hs578T cells; IC50 values varying from the 15.81 to 326.8 µM. Intracellular ROS (reactive oxygen species were quantified using a fluorescent probe 2’,7’-dichlorofluorescin diacetate (DCFH-DA. Only the treatment with 10 µM EGC and EGCG was able to induce a significant decrease of ROS concentration and increased levels of ROS were registered for 100 µM EGCG, EGC and GA. Flavans-3-ols and GA induced apoptosis in a dose- and time-dependent manner, which indicated that the induction of apoptosis mediated their cytotoxic activity at least partially. The galloylated catechins have shown a stronger antiproliferative activity and apoptotic effect than the one produced by non galloylated catechins. The galloylated flavan-3-ols are potential therapeutic agents for patients with triple negative breast cancer via induction of apoptosis.

  17. The antimicrobial possibilities of green tea

    Directory of Open Access Journals (Sweden)

    Wanda C Reygaert

    2014-08-01

    Full Text Available Green tea is a popular drink, especially in Asian countries, although its popularity continues to spread across the globe. The health benefits of green tea, derived from the leaves of the Camellia sinensis plant, have been studied for many years. Fairly recently, researchers have begun to look at the possibility of using green tea in antimicrobial therapy, and the potential prevention of infections. The particular properties of catechins found in the tea have shown promise for having antimicrobial effects. There are four main catechins (polyphenols found in green tea: (--epicatechin (EC, (--epicatechin-3-gallate (ECG, (--epigallocatechin (EGC, and (--epigallocatechin-3-gallate (EGCG. Three of these, ECG, EGC, and EGCG have been shown to have antimicrobial effects against a variety of organisms. These catechins have exhibited a variety of antimicrobial mechanisms. The results of studies on the antimicrobial effects of green tea have shown that the potential for preventive and therapeutic purposes is present. Further data collection on studies performed with human consumption during the course of infections, and studies on the occurrence of infections in populations that consume regular amounts of green tea will be necessary to complete the picture of its antimicrobial possibilities.

  18. Sorption of Tannin and Related Phenolic Compounds and Effects on Extraction of Soluble-N in Soil Amended with Several Carbon Sources

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    Javier M. Gonzalez

    2012-02-01

    Full Text Available Some tannins sorb to soil and reduce soluble-N. However, we know little about how they interact with organic amendments in soil. Soil (0–5 cm from plots, which were amended annually with various carbon substances, was treated with water (control or solutions containing tannins or related phenolic subunits. Treatments included a proanthocyanidin, catechin, tannic acid, β-1,2,3,4,6-penta-O-galloyl-D-glucose (PGG, gallic acid, and methyl gallate. We applied solutions of each of these materials to soil and measured soluble-C and -N in supernatants after application and following extraction with hot water (16 h, 80 °C. Sorption was low for non-tannin phenolics, methyl gallate, gallic acid, and catechin, and unaffected by amendment. Sorption of tannins, proanthocyanidin, tannic acid, and PGG, was higher and greater in plots amended with biosolids or manure. Extraction of soluble-N was not affected by amendment or by catechin, proanthocyanidin, or methyl gallate, but was reduced with PGG, tannic acid and gallic acid. Soil cation exchange capacity increased following treatment with PGG but decreased with gallic acid, irrespective of amendment. Tannins entering soil may thus influence soil organic matter dynamics and nutrient cycling but their impact may be influenced by the composition of soil organic matter.

  19. Mineral Components and Anti-oxidant Activities of Tropical Seaweeds

    Institute of Scientific and Technical Information of China (English)

    Suzuki Takeshi; Yoshie-Stark Yumiko; Santoso Joko

    2005-01-01

    Seaweeds are known to hold substances of high nutritional value; they are the richest resources of minerals important to the biochemical reactions in the human body. Seaweeds also hold non-nutrient compounds like dietary fiber and polyphenols. However, there is not enough information on the mineral compounds of tropical seaweeds. Also we are interested in the antioxidant activities of seaweeds, especially those in the tropical area. In this study, Indonesian green, brown and red algae were used as experimental materials with their mineral components analyzed by using an atomic absorption spectrophotometer. The catechins and flavonoids of these seaweeds were extracted with methanol and analyzed by high performance liquid chromatography (HPLC); the anti-oxidant activities of these seaweeds were evaluated in a fish oil emulsion system. The mineral components of tropical seaweeds are dominated by calcium, potassium and sodium, as well as small amounts of copper, iron and zinc. A green alga usually contains epigallocatechin, gallocatechin, epigallocatechin gallate and catechin. However, catechin and its isomers are not found in some green and red algae. In the presence of a ferrous ion catalyst, all the methanol extracts from the seaweeds show significantly lower peroxide values of the emulsion than the control,and that of a green alga shows the strongest anti-oxidant activity. The highest chelation on ferrous ions is also found in the extract of this alga, which is significantly different from the other methanol extracts in both 3 and 24 h incubations.

  20. New biflavonoid and other flavonoids from the leaves of Chimarrhis turbinata and their antioxidant activities

    International Nuclear Information System (INIS)

    A new biflavonol, named chimarrhoside (1), and eight known flavonol glycosides (2-9), were isolated from the leaves of Chimarrhis turbinata. Their structures were established on the basis of 1D and 2D NMR experiments as quercetin-3-O-rutinoside (2), kaempferol-3-O-rutinoside (3), kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside (4), quercetin-3-O-α-L-rhamnopyranosyl-(1→6)- β-D-galactopyranoside (5), 6-hydroxy-rutin (6), kaempferol-3-O-D-galactopyranoside (7), kaempferol-3-O-D-glucopyranoside (8) and kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-α-L-rhamnopyranosyl-(1→4)-β-D- glucopyranoside (9). In addition, catechin (10) and catechin-(4α→8)-catechin-procyanidin B-3) (11) were isolated. The crude extract, fractions and isolated compounds were evaluated for their antioxidative properties using an autographic assay based on β-carotene bleaching on TLC plates, and spectrophotometric detection by reduction of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. Flavonoids 2, 5, 6, 10 and 11 displayed strong free radical scavenging activity, when compared with the standards BHT and rutin. (author)

  1. Doped and undoped graphene platforms: the influence of structural properties on the detection of polyphenols

    Science.gov (United States)

    Chng, Chu'Er; Sofer, Zdenek; Pumera, Martin; Bonanni, Alessandra

    2016-02-01

    There is a huge interest in doped graphene and how doping can tune the material properties for the specific application. It was recently demonstrated that the effect of doping can have different influence on the electrochemical detection of electroactive probes, depending on the analysed probe, on the structural characteristics of the graphene materials and on the type and amount of heteroatom used for the doping. In this work we wanted to investigate the effect of doping on graphene materials used as platform for the detection of catechin, a standard probe which is commonly used for the measurement of polyphenols in food and beverages. To this aim we compared undoped graphene with boron-doped graphene and nitrogen doped graphene platforms for the electrochemical detection of standard catechin oxidation. Finally, the material providing the best electrochemical performance was employed for the analysis of real samples. We found that the undoped graphene, possessing lower amount of oxygen functionalities, higher density of defects and larger electroactive surface area provided the best electroanalytical performance for the determination of catechin in commercial beer samples. Our findings are important for the development of novel graphene platforms for the electrochemical assessment of food quality.

  2. Screening alpha-glucosidase and alpha-amylase inhibitors from natural compounds by molecular docking in silico.

    Science.gov (United States)

    Jhong, Chien-Hung; Riyaphan, Jirawat; Lin, Shih-Hung; Chia, Yi-Chen; Weng, Ching-Feng

    2015-01-01

    The alpha-glucosidase inhibitor is a common oral anti-diabetic drug used for controlling carbohydrates normally converted into simple sugars and absorbed by the intestines. However, some adverse clinical effects have been observed. The present study seeks an alternative drug that can regulate the hyperglycemia by down-regulating alpha-glucosidase and alpha-amylase activity by molecular docking approach to screen the hyperglycemia antagonist against alpha-glucosidase and alpha-amylase activities from the 47 natural compounds. The docking data showed that Curcumin, 16-hydroxy-cleroda-3,13-dine-16,15-olide (16-H), Docosanol, Tetracosanol, Antroquinonol, Berberine, Catechin, Quercetin, Actinodaphnine, and Rutin from 47 natural compounds had binding ability towards alpha-amylase and alpha-glucosidase as well. Curcumin had a better biding ability of alpha-amylase than the other natural compounds. Analyzed alpha-glucosidase activity reveals natural compound inhibitors (below 0.5 mM) are Curcumin, Actinodaphnine, 16-H, Quercetin, Berberine, and Catechin when compared to the commercial drug Acarbose (3 mM). A natural compound with alpha-amylase inhibitors (below 0.5 mM) includes Curcumin, Berberine, Docosanol, 16-H, Actinodaphnine/Tetracosanol, Catechin, and Quercetin when compared to Acarbose (1 mM). When taken together, the implication is that molecular docking is a fast and effective way to screen alpha-glucosidase and alpha-amylase inhibitors as lead compounds of natural sources isolated from medicinal plants. PMID:26154585

  3. Metabolic Changes of Caffeine in Tea Plant (Camellia sinensis (L.) O. Kuntze) as Defense Response to Colletotrichum fructicola.

    Science.gov (United States)

    Wang, Yu-Chun; Qian, Wen-Jun; Li, Na-Na; Hao, Xin-Yuan; Wang, Lu; Xiao, Bin; Wang, Xin-Chao; Yang, Ya-Jun

    2016-09-01

    Tea plant (Camellia sinensis) is one of the most economically valuable crops in the world. Anthracnose can affect the growth of leaves and cause serious yield losses of tea. Tea plants are rich in secondary metabolites; however, their roles in resistance to anthracnose are unclear. Herein we compared the contents of total phenolics, catechins, and caffeine in two cultivars with different resistances to anthracnose during Colletotrichum fructicola infection. (-)-Epigallocatechin-3-gallate (EGCG), (+)-catechin (C), caffeine, and critical regulatory genes were induced in C. fructicola-resistant tissues. In vitro antifungal tests showed that caffeine more strongly inhibited mycelial growth than tea polyphenols and catechins. Both electron microscopy and bioactivity analysis results showed that caffeine can affect mycelial cell walls and plasma membranes. Through promoter sequences analysis, a number of stress response-related cis-acting elements were identified in S-adenosylmethionine synthetase and tea caffeine synthase. These results demonstrated that (-)-EGCG, (+)-C, and caffeine may be involved in the resistance of tea plants to anthracnose. PMID:27541180

  4. Effects of season and plantation on phenolic content of unfermented and fermented Sri Lankan tea.

    Science.gov (United States)

    Jayasekera, Shiromani; Kaur, Lovedeep; Molan, Abdul-Lateef; Garg, Manohar L; Moughan, Paul J

    2014-01-01

    The effects of season and plantation on the polyphenol content of Camellia sinensis (tea) leaves were determined. Aqueous and organic extracts of freeze-dried fresh (unfermented) and black (fully-fermented) tea leaves were prepared for a structured set of samples (fermented and unfermented teas from six high-, mid- and low-grown plantations; fermented and unfermented teas from two harvesting seasons from four highland plantations), collected from the main tea-growing regions in Sri Lanka. Total catechin content and amounts of individual catechins, flavonols and theaflavins were determined by HPLC. Mean values for the phenolic constituents were generally significantly higher (pextraction. The mean values for total catechins, total flavonols and caffeine in the aqueous extracts from unfermented teas were 10.6%, 1.5% and 2.9%, respectively. For both unfermented and fermented tea leaves, a significant (p<0.05) interaction between plantation and season was observed for phenolic constituents. Ferric reducing antioxidant power was positively (p<0.05) correlated with (-)-epicatechin gallate and total phenolic contents. PMID:24444973

  5. Survey of antioxidant capacity and phenolic composition of blueberry, blackberry, and strawberry in Nanjing.

    Science.gov (United States)

    Huang, Wu-yang; Zhang, Hong-cheng; Liu, Wen-xu; Li, Chun-yang

    2012-02-01

    Berries are a good source of natural antioxidants. In the present study, the total antioxidant capacity and phenolic composition of three berry fruits (blueberry, blackberry, and strawberry) cultivated in Nanjing were investigated. Blueberry, with a Trolox equivalent antioxidant capacity (TEAC) value of 14.98 mmol Trolox/100 g dry weight (DW), exhibited the strongest total antioxidant capacity using both the 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. Blueberry also had the highest total phenolic content (TPC, 9.44 mg gallic acid/g DW), total flavonoid content (TFC, 36.08 mg rutin/g DW), and total anthocyanidin content (TAC, 24.38 mg catechin/g DW). A preliminary analysis using high performance liquid chromatography (HPLC) showed that the blueberry, blackberry, and strawberry samples tested contained a range of phenolic acids (including gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, p-coumaric acid, ferulic acid, ellagic acid, and cinnamic acid) and various types of flavonoids (flavone: luteolin; flavonols: rutin, myricetin, quercetrin, and quercetin; flavanols: gallocatechin, epigallocatechin, catechin, and catechin gallate; anthocyanidins: malvidin-3-galactoside, malvidin-3-glucoside, and cyanidin). In particular, the blueberries had high levels of proanthocyanidins and anthocyanidins, which might be responsible for their strong antioxidant activities. These results indicate a potential market role for berries (especially blueberries) as a functional food ingredient or nutraceutical. PMID:22302422

  6. New biflavonoid and other flavonoids from the leaves of Chimarrhis turbinata and their antioxidant activities

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Carmem L.; Silva, Dulce H.S.; Castro-Gamboa, Ian; Bolzani, Vanderlan da S. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica]. E-mail: bolzaniv@iq.unesp.br

    2005-11-15

    A new biflavonol, named chimarrhoside (1), and eight known flavonol glycosides (2-9), were isolated from the leaves of Chimarrhis turbinata. Their structures were established on the basis of 1D and 2D NMR experiments as quercetin-3-O-rutinoside (2), kaempferol-3-O-rutinoside (3), kaempferol-3-O-{alpha}-L-rhamnopyranosyl-(1{yields}6)-{beta}-D-galactopyranoside (4), quercetin-3-O-{alpha}-L-rhamnopyranosyl-(1{yields}6)- {beta}-D-galactopyranoside (5), 6-hydroxy-rutin (6), kaempferol-3-Oalactopyranoside (7), kaempferol-3-O-D-glucopyranoside (8) and kaempferol-3-O-{alpha}-L-rhamnopyranosyl-(1{yields}6)-{alpha}-L-rhamnopyranosyl-(1= {yields}4)-{beta}-D- glucopyranoside (9). In addition, catechin (10) and catechin-(4{alpha}{yields}8)-catechin-procyanidin B-3) (11) were isolated. The crude extract, fractions and isolated compounds were evaluated for their antioxidative properties using an autographic assay based on {beta}-carotene bleaching on TLC plates, and spectrophotometric detection by reduction of the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. Flavonoids 2, 5, 6, 10 and 11 displayed strong free radical scavenging activity, when compared with the standards BHT and rutin. (author)

  7. Mineral components and anti-oxidant activities of tropical seaweeds

    Science.gov (United States)

    Takeshi, Suzuki; Yumiko, Yoshie-Stark; Joko, Santoso

    2005-07-01

    Seaweeds are known to hold substances of high nutritional value; they are the richest resources of minerals important to the biochemical reactions in the human body. Seaweeds also hold non-nutrient compounds like dietary fiber and polyphenols. However, there is not enough information on the mineral compounds of tropical seaweeds. Also we are interested in the antioxidant activities of seaweeds, especially those in the tropical area. In this study, Indonesian green, brown and red algae were used as experimental materials with their mineral components analyzed by using an atomic absorption spectrophotometer. The catechins and flavonoids of these seaweeds were extracted with methanol and analyzed by high performance liquid chromatography (HPLC); the antioxidant activities of these seaweeds were evaluated in a fish oil emulsion system. The mineral components of tropical seaweeds are dominated by calcium, potassium and sodium, as well as small amounts of copper, iron and zinc. A green alga usually contains epigallocatechin, gallocatechin, epigallocatechin gallate and catechin. However, catechin and its isomers are not found in some green and red algae. In the presence of a ferrous ion catalyst, all the methanol extracts from the seaweeds show significantly lower peroxide values of the emulsion than the control, and that of a green alga shows the strongest antioxidant activity. The highest chelation on ferrous ions is also found in the extract of this alga, which is significantly different from the other methanol extracts in both 3 and 24 h incubations.

  8. GREEN TEA: A MAGICAL HERB WITH MIRACULOUS OUTCOMES

    Directory of Open Access Journals (Sweden)

    Anand Jigisha

    2012-05-01

    Full Text Available Green tea in its purest and most unadulterated form has always influenced human health from generations and day by day scientific evidences throughout the world are making people aware of health benefits associated with this herbal drink. Though Green Tea is not officially recognized as a medical agent, it is one of the most researched plant-based remedies whose possible benefits include promotion of cardio-vascular health, cancer prevention, skin protection, and antioxidant activity, to fight high cholesterol levels, infection, impaired immune function, diarrhoea, fatigue and many more. Laboratory findings have revealed that notable health benefit of green tea is its powerful antioxidants potential which at the molecular level, helps prevent cellular damage from certain oxidation reactions in the body. The credit for their useful antioxidant property lies with their huge collection of chemical substances called polyphenols and catechins make the major contribution of them. Though catechins have been found in other plants derivatives such as grapes, pomegranates, those found in tea have proven to be the most effective antioxidants known. The catechins epigallocatechin gallate (EGCG is found in the greatest concentration and most studied for its health benefits. There is an urgent need to check the efficacy, safety and translational guidelines for a green tea to be used as safe, effective drug. The main objective of this review is to enlighten some recent facts with relevance to the current status and advance in green tea benefits.

  9. Differences in the Phenolic Composition and Antioxidant Properties between Vitis coignetiae and Vitis vinifera Seeds Extracts

    Directory of Open Access Journals (Sweden)

    Ryszard Amarowicz

    2013-03-01

    Full Text Available Phenolic compounds were extracted from European and Japanese grapevine species (Vitis vinifera and V. coignetiae seeds using 80% methanol or 80% acetone. The total content of phenolic compounds was determined utilizing Folin-Ciocalteu’s phenol reagent, while the content of tannins was assayed by the vanillin and BSA precipitation methods. Additionally, the DPPH free radical and ABTS cation radical scavenging activities and the reduction power of the extracts were measured. The HPLC method was applied to determine the phenolic compounds, such as phenolic acids and catechins. The seeds contained large amounts of tannins and gallic acid and observable quantities of catechins, p-coumaric, ferulic and caffeic acids. The dominant form of phenolic acids in the extracts was the ester-bound form. The content of total phenolics was higher in the European grape V. vinifera seeds, which also contained more tannins, catechins and phenolic acids, except for caffeic acid. Extracts from V. vinifera seeds showed better radical scavenger properties and stronger reducing power. The total contents of phenolic compounds and tannins in acetone extracts were higher than in methanolic extracts. Acetone extracts also exhibited stronger antiradical properties as well as stronger reducing power.

  10. Liquid chromatography tandem mass spectrometry identification of proanthocyanidins in rat plasma after oral administration of grape seed extract

    Science.gov (United States)

    Prasain, Jeevan K.; Peng, Ning; Dai, Yanying; Moore, Ray; Arabshahi, Alireza; Wilson, Landon; Barnes, Stephen; Wyss, J. Michael; Kim, Helen; Watts, Ray L.

    2009-01-01

    Proanthocyanidin rich plant extracts derived from grape seed extract (GSE), hawthorn and cranberry are on markets for their preventive effects against cardiovascular diseases and uroinfections in woman. However, the importance of these health beneficial effects of these botanicals remains elusive due to incomplete understanding of uptake, metabolism and bioavailability of proanthocyanidins in vivo. In the present study rats were given GSE orally (300 mg/kg, twice a day) and blood and urine were collected over a 24 h period. Monomeric catechins and their methylated metabolites, and proanthocyanidins up to trimers were detected in blood samples treated with GSE using LC-MS/MS operating in the multiple reaction monitoring (MRM) mode. A new tetramethylated metabolite of dimeric proanthocyanidin (m/z 633) in GSE-treated urine was tentatively identified. Using LC-MS/MS, (+)-catechin and (−)-epicatechin were identified in the brain conclusively. These data suggested that GSE catechins cross the blood brain barrier and may be responsible for the neuroprotective effects of GSE. PMID:19095430

  11. Growth inhibition and apoptosis in cancer cells induced by polyphenolic compounds of Acacia hydaspica: Involvement of multiple signal transduction pathways.

    Science.gov (United States)

    Afsar, Tayyaba; Trembley, Janeen H; Salomon, Christine E; Razak, Suhail; Khan, Muhammad Rashid; Ahmed, Khalil

    2016-01-01

    Acacia hydaspica R. Parker is known for its medicinal uses in multiple ailments. In this study, we performed bioassay-guided fractionation of cytotoxic compounds from A. hydaspica and investigated their effects on growth and signaling activity in prostate and breast cancer cell lines. Four active polyphenolic compounds were identified as 7-O-galloyl catechin (GC), catechin (C), methyl gallate (MG), and catechin-3-O-gallate (CG). The four compounds inhibited prostate cancer PC-3 cell growth in a dose-dependent manner, whereas CG and MG inhibited breast cancer MDA-MB-231 cell growth. All tested compounds inhibited cell survival and colony growth in both cell lines, and there was evidence of chromatin condensation, cell shrinkage and apoptotic bodies. Further, acridine orange, ethidium bromide, propidium iodide and DAPI staining demonstrated that cell death occurred partly via apoptosis in both PC-3 and MDA-MB-231 cells. In PC-3 cells treatment repressed the expression of anti-apoptotic molecules Bcl-2, Bcl-xL and survivin, coupled with down-regulation of signaling pathways AKT, NFκB, ERK1/2 and JAK/STAT. In MDA-MB-231 cells, treatment induced reduction of CK2α, Bcl-xL, survivin and xIAP protein expression along with suppression of NFκB, JAK/STAT and PI3K pathways. Our findings suggest that certain polyphenolic compounds derived from A. hydaspica may be promising chemopreventive/therapeutic candidates against cancer. PMID:26975752

  12. Characterization and Physicochemical Properties of Condensed Tannins from Acacia catechu.

    Science.gov (United States)

    Duval, Antoine; Avérous, Luc

    2016-03-01

    Condensed tannins from Acacia catechu were carefully studied to determine their chemical structure and physicochemical properties. The combined use of MALDI-TOF-MS and (13)C NMR revealed that catechin and epicatechin are the predominant monomers. Most of the compounds were dimers, as confirmed by size exclusion chromatography measurements. To evaluate their potential as aromatic building block in polymer synthesis, special care was given to the characterization and quantification of the different OH groups. A detailed (31)P NMR analysis showed the predominance of catechin, with a catechin/epicatechin ratio of 4.2:1. Two distinct (1)H NMR measurements confirmed the quantification. The thermal properties were also determined: the tannins showed a high temperature of degradation (ca. 190 °C) and a high glass transition temperature (ca. 140 °C), allowing for thermal processing or chemical reactions at relatively high temperature. A. catechu tannins thus present interesting features to be used as aromatic building blocks in polymer materials. PMID:26853705

  13. Flavanols and Anthocyanins in Cardiovascular Health: A Review of Current Evidence

    Directory of Open Access Journals (Sweden)

    Sonia de Pascual-Teresa

    2010-04-01

    Full Text Available Nowadays it is accepted that natural flavonoids present in fruits and plant-derived-foods are relevant, not only for technological reasons and organoleptic properties, but also because of their potential health-promoting effects, as suggested by the available experimental and epidemiological evidence. The beneficial biological effects of these food bioactives may be driven by two of their characteristic properties: their affinity for proteins and their antioxidant activity. Over the last 15 years, numerous publications have demonstrated that besides their in vitro antioxidant capacity, certain phenolic compounds, such as anthocyanins, catechins, proanthocyanidins, and other non coloured flavonoids, may regulate different signaling pathways involved in cell survival, growth and differentiation. In this review we will update the knowledge on the cardiovascular effects of anthocyanins, catechins and proanthocyanidins, as implied by the in vitro and clinical studies on these compounds. We also review the available information on the structure, distribution and bioavailability of flavanols (monomeric catechins and proanthocyanidins and anthocyanins, data necessary in order to understand their role in reducing risk factors and preventing cardiovascular health problems through different aspects of their bioefficacy on vascular parameters (platelet agregation, atherosclerosis, blood pressure, antioxidant status, inflammation-related markers, etc., myocardial conditions, and whole-body metabolism (serum biochemistry, lipid profile, highlighting the need for better-designed clinical studies to improve the current knowledge on the potential health benefits of these flavonoids to cardiovascular and metabolic health.

  14. Pharmacokinetics and biotransformation of tea polyphenols.

    Science.gov (United States)

    Qiao, Jinping; Kong, Xiangyi; Kong, Aiying; Han, Mei

    2014-01-01

    Tea is an infusion of the leaves of the Camellia sinensis plant and is the most widely consumed beverage in the world after water. The main chemical components in teas are phenolic compounds (tea polyphenols, mainly tea catechins). A large number of in vitro and in vivo scientific studies have supported that the tea polyphenols can provide a number of health benefits such as, reducing the incidence of coronary heart disease, diabetes and cancer. Recently, tea polyphenols have proven highly attractive as lead compounds for drug discovery programs. A clear understanding of chemistry, stability, pharmacokinetics and metabolic fate of tea will be significant to elucidate many medicinal effects by biochemical theory and pharmaceutical development. This article reviews the current literature on the pharmacoknetics and biotransformation of tea catechins. The half-lives of tea polyphenols are 2-4h and their absorption and elimination are rapid in humans. The peak times (tmax) are 1 and 3 h after oral administration and the peak plasma concentrations are low μM range. It has been reported that catechins are easily metabolized by enzyme and microbe, and the main metabolic pathways are methylation, glucuronidation, sulfation, ring-fission metabolism, and so on. The information is important to discuss some of the challenges and benefits of pursuing this family of compounds for drug discovery. PMID:24527703

  15. Profile of urinary and fecal proanthocyanidin metabolites from common cinnamon (Cinnamomum zeylanicum L.) in rats.

    Science.gov (United States)

    Mateos-Martín, María Luisa; Pérez-Jiménez, Jara; Fuguet, Elisabet; Torres, Josep Lluís

    2012-04-01

    Cinnamon (Cinnamomum zeylanicum L.) bark is widely used as a spice and in traditional medicine. Its oligomeric and polymeric proanthocyanidins are believed to be partly responsible for the beneficial properties of the plant. We describe here the metabolic fate of cinnamon proanthocyanidins in the urine and feces of rats fed a suspension of the whole bark. The metabolites include ten mono-, di-, and tri- conjugated (epi)catechin phase II metabolites and more than 20 small phenolic acids from intestinal microbial fermentation. Some of these are sulfated conjugates. Feces contain intact (epi)catechin and dimers. This suggests that free radical scavenging species are in contact with the intestinal walls for hours after ingestion of cinnamon. The phenolic metabolite profile of cinnamon bark in urine is consistent with a mixture of proanthocyanidins that are depolymerized into their constitutive (epi)catechin units as well as cleaved into smaller phenolic acids during their transit along the intestinal tract, with subsequent absorption and conjugation into bioavailable metabolites. PMID:22383303

  16. Influence of galloyl moiety in interaction of epicatechin with bovine serum albumin: a spectroscopic and thermodynamic characterization.

    Directory of Open Access Journals (Sweden)

    Sandip Pal

    Full Text Available The health benefits stemming from green tea are well known, but the exact mechanism of its biological activity is not elucidated. Epicatechin (EC and epicatechin gallate (ECG are two dietary catechins ubiquitously present in green tea. Serum albumins functionally carry these catechins through the circulatory system and eliminate reactive oxygen species (ROS induced injury. In the present study ECG is observed to have higher antioxidant activity; which is attributed to the presence of galloyl moiety. The binding affinity of these catechins to bovine serum albumin (BSA will govern the efficacy of their biological activity. EC and ECG bind with BSA with binding constants 1.0 × 10(6 M(-1 and 6.6 × 10(7 M(-1, respectively. Changes in secondary structure of BSA on interaction with EC and ECG have been identified by circular dichroism (CD and Fourier transform infrared (FT-IR spectroscopy. Thermodynamic characterization reveals the binding process to be exothermic, spontaneous and entropy driven. Mixed binding forces (hydrophobic, electrostatic and hydrogen bonding exist between ECG and BSA. Binding site for EC is primarily site-II in sub-domain IIIA of BSA and for ECG; it is site-I in sub-domain IIA. ECG with its high antioxidant activity accompanied by high affinity for BSA could be a model in drug designing.

  17. Profiling of lipophilic and phenolic phytochemicals of four cultivars from cherimoya (Annona cherimola Mill.).

    Science.gov (United States)

    Santos, Sónia A O; Vilela, Carla; Camacho, João F; Cordeiro, Nereida; Gouveia, Manuela; Freire, Carmen S R; Silvestre, Armando J D

    2016-11-15

    The lipophilic and phenolic extractives of the ripe mesocarp of four cherimoya cultivars ('Perry Vidal', 'Mateus I', 'Mateus III' and 'Funchal') from Madeira Island, were studied for the first time. The predominant lipophilic compounds are kaurene diterpenes (42.2-59.6%), fatty acids (18.0-35.6%) and sterols (9.6-23.7%). Kaur-16-en-19-oic acid is the major lipophilic component of all cultivars accounting between 554 and 1350mgkg(-1) of dry material. The studied fruits also contain a high variety of flavan-3-ols, including galloylated and non-galloylated compounds. Five phenolic compounds were identified for the first time: catechin, (epi)catechin-(epi)gallocatechin, (epi)gallocatechin, (epi)afzelechin-(epi)catechin and procyanidin tetramer. 'Mateus I' and 'Mateus III' cultivars present the highest content of phenolic compounds (6299 and 9603mgkg(-1) of dry weight, respectively). These results support the use of this fruit as a rich source of health-promoting components, with the capacity to prevent or delay the progress of oxidative-stress related disorders. PMID:27283704

  18. Moderate acute intake of de-alcoholised red wine, but not alcohol, is protective against radiation-induced DNA damage ex vivo-Results of a comparative in vivo intervention study in younger men

    International Nuclear Information System (INIS)

    Moderate intake of wine is associated with reduced risk of cardiovascular disease and possibly cancer however it remains unclear whether the potential health benefits of wine intake are due to alcohol or the non-alcoholic fraction of wine. We therefore tested the hypothesis that the non-alcoholic fraction of wine protects against genome damage induced by oxidative stress in a crossover intervention study involving six young adult males aged 21-26 years. The participants adhered to a low plant phenolic compound diet for 48 h prior to consuming 300 mL of complete red wine, dealcoholised red wine or ethanol on separate occasions 1 week apart. Blood samples were collected 0.5, 1.0 and 2.0 h after beverage consumption. Baseline and radiation-induced genome damage was measured using the cytokinesis-block micronucleus assay and total plasma catechin concentration was measured. Consumption of dealcoholised red wine significantly decreased the gamma radiation-induced DNA damage at 1 and 2 h post-consumption by 20%. In contrast alcohol tended to increase radiation-induced genome damage and complete wine protected against radiation-induced genome damage relative to alcohol. The observed effects were only weakly correlated with the concentration of total plasma catechin (R = -0.23). These preliminary data suggest that only the non-alcoholic fraction of red wine protects DNA from oxidative damage but this effect cannot be explained solely by plasma catechin

  19. A Review on the Beneficial Effects of Tea Polyphenols on Human Health

    Directory of Open Access Journals (Sweden)

    J. Gupta

    2008-01-01

    Full Text Available The aim of this review is to focus some light on the beneficial effects of the tea polyphenols on human health, based on various laboratory, epidemiological and clinical studies carried out on tea and tea polyphenols in the last few years. Tea is second only to water as the most consumed beverage in the world. Tea has been consumed worldwide since ancient times to maintain and improve health. The health benefits associated with tea consumption have resulted in the wide inclusion of green tea extracts in botanical dietary supplements, which are widely consumed as adjuvants for complementary and alternative medicines. Depending upon the level of fermentation, tea can be categorized into three types: green (unfermented, oolong (partially fermented and black (highly to fully fermented. Black tea represents approximately 78% of total consumed tea in the world, whereas green tea accounts for approximately 20% of tea consumed. Tea is particularly rich in polyphenols, including catechins, theaflavins and thearubigins, which are thought to contribute to the health benefits of tea. Tea polyphenols comprise about one-third of the weight of the dried leaf and they exhibit biochemical and pharmacological activities including antioxidant activities, inhibition of cell proliferation, induction of apoptosis, cell cycle arrest and modulation of carcinogen metabolism. Several studies demonstrate that most tea polyphenols exert their effects by scavenging Reactive Oxygen Species (ROS since excessive production of ROS has been implicated in the development of a variety of ailments including cancer of the prostate gland (CaP. Tea catechins include (--epicatechin (EC,(--epigallocatechin (EGC, (--epicatechin gallate (ECG and (--epigallocatechin gallate (EGCG. These catechins have been shown to be epimerized to (--catechin (C, (--gallocatechin (GC, (--catechin gallate (CG and (--gallocatechin gallate (GCG, respectively, during heat treatment. Tea polyphenols act as

  20. Pro‑apoptotic effects of pycnogenol on HT1080 human fibrosarcoma cells.

    Science.gov (United States)

    Harati, Kamran; Slodnik, Pawel; Chromik, Ansgar Michael; Behr, Björn; Goertz, Ole; Hirsch, Tobias; Kapalschinski, Nicolai; Klein-Hitpass, Ludger; Kolbenschlag, Jonas; Uhl, Waldemar; Lehnhardt, Marcus; Daigeler, Adrien

    2015-04-01

    Complete surgical resection with clear margins remains the mainstay of therapy for localised fibrosarcomas. Nevertheless, metastatic fibrosarcomas still represent a therapeutic dilemma. Commonly used chemotherapeutic agents like doxorubicin have proven to be effective in pycnogenol and its constituents on human fibrosarcoma cells (HT1080). Ten healthy subjects (six females, four males, mean age 24.8 ± 6 years) received a single dose of 300 mg pycnogenol orally. Blood plasma samples were obtained before and 6 h after intake of pycnogenol. HT1080 cells were treated with these plasma samples. Additionally, HT1080 were incubated separately with catechin, epicatechin and taxifolin that are known as the main constituents of pycnogenol. Vital, apoptotic and necrotic cells were quantified using flow cytometric analysis. Gene expression was analyzed by RNA microarray. The results showed that single application of taxifolin, catechin and epicatechin reduced cell viability of HT1080 cells only moderately. A single dose of 300 mg pycnogenol given to 10 healthy adults produced plasma samples that led to significant apoptotic cell death ex vivo whereas pycnogenol-negative serum displayed no apoptotic activity. Microarray analysis revealed remarkable expression changes induced by pycnogenol in a variety of genes, which are involved in different apoptotic pathways of cancer cells [Janus kinase 1 (JAK1), DUSP1, RHOA, laminin γ1 (LAMC1), fibronectin 1 (FN1), catenin α1 (CTNNA1), ITGB1]. In conclusion, metabolised pycnogenol induces apoptosis in human fibrosarcoma cells. Pycnogenol exhibits its pro-apoptotic activity as a mixture and is more effective than its main constituents catechin, epicatechin and taxifolin indicating that the metabolised components interact synergistically. These results provide experimental support for in vivo trials assessing the effect of the pine bark extract pycnogenol. PMID:25625225

  1. Electronic nose and chiral-capillary electrophoresis in evaluation of the quality changes in commercial green tea leaves during a long-term storage.

    Science.gov (United States)

    Mirasoli, Mara; Gotti, Roberto; Di Fusco, Massimo; Leoni, Alberto; Colliva, Carolina; Roda, Aldo

    2014-11-01

    Electronic nose and capillary electrophoresis were applied in quality control of green tea samples subjected to long-term storage. Twelve representative green teas were considered, available as an "aged" (tea leaves stored during a long-term period of two years) and/or "not aged" (fresh products) samples. Their infusions were analyzed by an electronic nose, equipped with an array of six metal oxide semiconductor (MOS) sensors to obtain olfactive fingerprints of the volatile compounds in the infusions headspace. Upon training and chemometric analysis of acquired data (linear discriminant analysis), the electronic nose was found to be able in correctly classifying unknown samples as "aged" or "not aged". Concomitantly, the infusion samples were analyzed by Cyclodextrin-modified Micellar Electrokinetic Chromatography (CD-MEKC) for determination of catechins. The analysis of seven most represented catechins and the methylxanthines theobromine and caffeine revealed a general loss of the polyphenols in each of the considered aged samples (up to 45%, w/w). In addition, the applied enantioselective method based on (2-hydroxypropyl)-β-cyclodextrin (HP-βCD) as chiral selector, was exploited for the estimation of (+)-Gallocatechin in the presence of (-)-Gallocatechin; the latter, as the non-native enantiomer, can be associated to the epimerisation of (-)-Epigallocatechin and was assumed as a marker occurring in case of uncorrected storage conditions of tea leaves. Interestingly, it was observed that epimerization did not significantly occur during aging. The application of CD-MEKC and electronic nose allowed for a fast characterization of green teas taking into account that the aroma is a decisive parameter for the acceptance of the product, whereas the catechins content is associated to the biological value. PMID:25127562

  2. Survey of antioxidant capacity and phenolic composition of blueberry, blackberry, and strawberry in Nanjing

    Institute of Scientific and Technical Information of China (English)

    Wu-yang HUANG; Hong-cheng ZHANG; Wen-xu LIU; Chun-yang LI

    2012-01-01

    Berries are a good source of natural antioxidants.In the present study,the total antioxidant capacity and phenolic composition of three berry fruits (blueberry,blackberry,and strawberry) cultivated in Nanjing were investigated.Blueberry,with a Trolox equivalent antioxidant capacity (TEAC) value of 14.98 mmol Trolox/100 g dry weight (DW),exhibited the strongest total antioxidant capacity using both the 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt (ABTS) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods.Blueberry also had the highest total phenolic content (TPC,9.44 mg gallic acid/g DW),total flavonoid content (TFC,36.08 mg rutin/g DW),and total anthocyanidin content (TAC,24.38 mg catechin/g DW).A preliminary analysis using high performance liquid chromatography (HPLC) showed that the blueberry,blackberry,and strawberry samples tested contained a range of phenolic acids (including gallic acid,protocatechuic acid,p-hydroxybenzoic acid,vanillic acid,caffeic acid,p-coumaric acid,ferulic acid,ellagic acid,and cinnamic acid) and various types of flavonoids (flavone:luteolin; flavonols:rutin,myricetin,quercetrin,and quercetin; flavanols:gallocatechin,epigallocatechin,catechin,and catechin gallate; anthocyanidins:malvidin-3-galactoside,malvidin-3-glucoside,and cyanidin).In particular,the blueberries had high levels of proanthocyanidins and anthocyanidins,which might be responsible for their strong antioxidant activities.These results indicate a potential market role for berries (especially blueberries) as a functional food ingredient or nutraceutical.

  3. Determination of Major-to-Trace Minerals and Polyphenols in Different Apple Cultivars

    Directory of Open Access Journals (Sweden)

    Doina Adina TODEA

    2014-12-01

    Full Text Available The aim of this study was to investigate the concentration level of some major-to-trace elements and toxic minerals and polyphenols (catechin, epicatechin and quercetin in fruits belonging to different apple cultivars (‘Auriu de Cluj’, ‘Florina’, ‘Generos’, ‘Golden Delicious’, ‘Prima’, ‘Productiv de Cluj’ and ‘Starkrimson’, under specific climate conditions to northwestern Romania. The apple minerals were determined by the inductively coupled plasma mass spectrometry (ICP-MS and inductively coupled plasma optical emission spectrometry (ICP-OES after a preliminary, microwave-assisted, acid digestion. The polyphenols were determined by high performance liquid chromatography (HPLC with MS/MS detection. According to the obtained results, the edible part of the apple contains many minerals with high relative nutritional value (RNV. The major minerals (Na, K, Ca, Mg and P, minor elements (Cu, Fe, Mn, Sr and Zn and toxic trace elements (Cd, Cr and Pb were comparatively identified and quantified. It was found that K (31976 mg/kg was predominant among the major elements, while Fe (3.68 mg/kg and Cu (3.57 mg/kg were comparable. The toxic trace metals (Cd, Cr and Pb were below the limits of detection (0.01, 0.10 and 0.01 mg/kg, respectively and did not determine any health risk to consumers. The main polyphenols composition (catechin, epicathechin, quercetin differs slightly among different cultivars. In ‘Idared’ and ‘Jonathan’ cultivars, the investigated polyphenols are in higher quantities comparing to the others. In all investigated apple cultivars, quercetin was proved to be the major polyphenol, followed by epicathechin and catechin. These results suggest that, regarding only the investigated polyphenols, ‘Idared’ and ‘Jonathan’ cultivars have the highest antioxidant character in all investigated genotypes.

  4. Photodegradation of (-)-epigallocatechin-3-gallate in topical cream formulations and its photostabilization.

    Science.gov (United States)

    Bianchi, Anna; Marchetti, Nicola; Scalia, Santo

    2011-12-01

    The aim of the study was to examine the photostability of the major catechin of green tea, (-)-epigallocatechin-3-gallate (EGCG), which possesses important antioxidant and skin photoprotective properties. In order to simulate realistic conditions of use of topical preparations, the photolysis studies were performed in model creams (oil-in-water emulsions) containing 1% (w/w) EGCG and exposed to a solar simulator at an irradiance corresponding to natural sunlight. The extent of photodegradation was measured by HPLC-UV and HPLC-ESI-MS. EGCG was found to decompose by 68.9±2.3%, after 1h irradiation. Addition of the coantioxidants, vitamin E or butylated hydroxytoluene to the emulsion formulation, significantly enhanced the photolability of the catechin, the EGCG loss reached 85.7±1.3% and 80.5±1.4%, respectively. On the other hand, inclusion of the UVB (290-320nm) filter, ethylhexyl methoxycinnamate in the cream produced a small but significant reduction of EGCG photodegradation to 61.0±2.9%, while the UVA (320-400nm) filter, butyl methoxydibenzoylmethane was ineffective (EGCG degradation, 67.8±1.5%). A more marked decrease in the light-induced decomposition of EGCG to 51.6±2.7% was achieved, under the same conditions, using the water-soluble UVB filter, benzophenone-4 (BP-4). This effect was concentration dependent, maximal EGCG photostabilization (catechin loss, 29.4±2.2%) was attained in the presence of 2.1% (w/w) BP-4. Therefore, BP-4 represents a useful additive to improve the light stability of EGCG in topical formulations for skin photoprotection. PMID:21807473

  5. Quantitative analysis of flavan-3-ols in Spanish foodstuffs and beverages.

    Science.gov (United States)

    de Pascual-Teresa, S; Santos-Buelga, C; Rivas-Gonzalo, J C

    2000-11-01

    An HPLC method, using detection after postcolumn derivatization with p-dimethylaminocynnamaldehyde (DMACA), was developed for the quantitative analysis of individual flavanols in food. This method was applied to flavanol determination in 56 different kinds of Spanish food products, including fruit, vegetables, legumes, beverages (cider, coffee, beer, tea, and wine), and chocolate. The determined compounds corresponded to the catechins and proanthocyanidin dimers and trimers usually present in food and, therefore, they were representative of the flavanols of low degree of polymerization consumed with the diet. The data generated could be used for calculation of the dietary intake of either individual or total flavanols, which would allow the further establishment of epidemiological correlations with the incidence of chronic diseases. Similar flavanol profiles were found in the different samples of a similar type of product, even though important variations could exist in the concentrations of total and individual flavanols among them. This was attributed to factors such as sample origin, stage of ripeness, post-harvesting conservation, and processing. Total flavanol contents varied from nondetectable in most of the vegetables to 184 mg/100 g found in a sample of broad bean. Substantial amounts were also found in some fruits, such as plum and apple, as well as in tea and red wine. Epicatechin was the most abundant flavanol, followed by catechin and procyanidin B2. In general, catechins were found in all the flavanol-containing products, but the presence of gallocatechins was only relevant in pomegranate, broad bean, lentil, grape, wine, beer, and tea, and most of the berries. Galloyled flavanols were only detected in strawberry, medlar, grape, and tea. PMID:11087482

  6. HPLC-MS/MS Analysis of Poly phenols in Different Fermented Type Tea Products Prepared from Camellia sinensis'Baiye Dancong'%白叶单枞不同发酵茶中多酚类成分的HPLC-MS/MS分析

    Institute of Scientific and Technical Information of China (English)

    苗爱清; 程悦; 梁祈; 赵超艺; 凌彩金; 庞式; 王冬梅

    2011-01-01

    Chemical compositions of broken black tea, oolong tea and dark tea prepared from Camellia sinensis ‘Baiye Dancong’ were analyzed by HPLC-MS/MS method.Comparing the UV absorption spectra and mass spectra of the peaks in the obtained HPLC chromatograms with those of the authentic standards and related literatures, 32, 30 and 14 compounds were identified from broken black tea, oolong tea and dark tea respectively.These compounds included catechins, alkaloids.Some non-catechin polyphenol compounds such as flavonol glycosides with kaempferol, quercetin and myricitin as aglycones, and catechin polymers such as theasinensins were also identified.%采用HPLC-MS/MS对以白叶单枞茶为原料生产的红碎茶、乌龙茶、黑茶进行分析,通过对紫外吸收光谱以及质谱信息进行分析,并参考相关文献,推定出白叶单枞红茶中32个化合物,乌龙茶中30个化合物,黑茶中14个化合物.这些化合物中包括常见的儿茶素类化合物、生物碱.此外还检测到多种以山奈酚、槲皮素、杨梅素为苷元的黄酮醇苷等非儿茶素类茶多酚和茶双没食子儿茶素等儿茶素聚合物.

  7. Rapid assessment of bioactive phenolics and methylxanthines in spent coffee grounds by FT-NIR spectroscopy.

    Science.gov (United States)

    Magalhães, Luís M; Machado, Sandia; Segundo, Marcela A; Lopes, João A; Páscoa, Ricardo N M J

    2016-01-15

    Spent coffee grounds (SCGs) are a great source of bioactive compounds with interest to pharmaceutical and cosmetic industries. Phenolics and methylxanthines are the main health related compounds present in SCG samples. Content estimation of these compounds in SCGs is of upmost importance in what concerns their profitable use by waste recovery industries. In the present work, near-infrared spectroscopy (NIRS) was proposed as a rapid and non-destructive technique to assess the content of three main phenolics (caffeic acid, (+)-catechin and chlorogenic acid) and three methylxanthines (caffeine, theobromine and theophylline) in SCG samples obtained from different coffee brands and diverse coffee machines. The content of these compounds was determined for 61 SCG samples by HPLC coupled with diode-array detection. Partial least squares (PLS) regression based models were calibrated to correlate diffuse reflectance NIR spectra against the reference data for the six parameters obtained by HPLC. Spectral wavelength selection and number of latent variables were optimized by minimizing the cross-validation error. PLS models showed good linearity with a coefficient of determination for the prediction set (Rp(2)) of 0.95, 0.92, 0.88, 071 and 0.84 for caffeine, caffeic acid, (+)-catechin, chlorogenic acid and theophylline, respectively. The range error ratio (RER) was higher for caffeine (17.8) when compared to other compounds (12.0, 10.1, 7.6 and 9.2, respectively for caffeic acid, (+)-catechin, chlorogenic acid and theophylline). Moreover, the content of caffeine could be used to predict the antioxidant properties of SCG samples (R=0.808, n=61), despite not presenting this property itself. The results obtained confirmed that NIRS is a suitable technique to screen SCG samples unveiling those with high content of bioactive compounds, which are interesting for subsequent extraction procedures. PMID:26592633

  8. Application of Pseudomonas fluorescens to Blackberry under Field Conditions Improves Fruit Quality by Modifying Flavonoid Metabolism.

    Directory of Open Access Journals (Sweden)

    Daniel Garcia-Seco

    Full Text Available Application of a plant growth promoting rhizobacterium (PGPR, Pseudomonas fluorescens N21.4, to roots of blackberries (Rubus sp. is part of an optimised cultivation practice to improve yields and quality of fruit throughout the year in this important fruit crop. Blackberries are especially rich in flavonoids and therefore offer potential benefits for human health in prevention or amelioration of chronic diseases. However, the phenylpropanoid pathway and its regulation during ripening have not been studied in detail, in this species. PGPR may trigger flavonoid biosynthesis as part of an induced systemic response (ISR given the important role of this pathway in plant defence, to cause increased levels of flavonoids in the fruit. We have identified structural genes encoding enzymes of the phenylpropanoid and flavonoid biosynthetic pathways catalysing the conversion of phenylalanine to the final products including flavonols, anthocyanins and catechins from blackberry, and regulatory genes likely involved in controlling the activity of pathway branches. We have also measured the major flavonols, anthocyanins and catechins at three stages during ripening. Our results demonstrate the coordinated expression of flavonoid biosynthetic genes with the accumulation of anthocyanins, catechins, and flavonols in developing fruits of blackberry. Elicitation of blackberry plants by treatment of roots with P.fluorescens N21.4, caused increased expression of some flavonoid biosynthetic genes and an accompanying increase in the concentration of selected flavonoids in fruits. Our data demonstrate the physiological mechanisms involved in the improvement of fruit quality by PGPR under field conditions, and highlight some of the genetic targets of elicitation by beneficial bacteria.

  9. Molecular Mechanisms and Biological Implications of Green Tea Polyphenol (--Epigallocatechin -3- gallate

    Directory of Open Access Journals (Sweden)

    Subramani C

    2013-07-01

    Full Text Available Plants constitute a vital part of the biological system in which we exist and are indispensable to humans in every aspect of life. Its major percentage of naturally occurring material used as drugs by people all over the world. The use of plants as food and medicines when man started his life on this planet. Now people started to realize the value of plants as drugs after they felt the serious side effects of modern medicine. The practice of wide usage of plants as medicinal agents is prevalent for centuries in various parts of the world, the most prominent of which are Chinese system of medicine, ayurvedic, siddha and unani system of medicine in India. The realization that there is something interesting in the properties of these medicinal plants dawned with the advent of chemistry in the late 18th century. Chemists gradually started isolating pure substances from various anatomical parts of medicinal plants and concluded that certain active compounds are responsible for the therapeutic actions of the plants. It has been estimated that only 10-15 % of 2,50,000 to 7,50,000 existing species of higher plants have been surveyed for biologically active compounds for the study of its phytochemistry and pharmacology. This review paper deals with the advances in study of green tea, which is the second most consumed beverage in the Worldafter water. Green tea catechins are the flavan-3-ols found in green tea leaves, of the catechins. Out of the various catechins found in green tea, (--Epigallocatechin-3-gallate (EGCG is the most abundant one in green tea leaves. It is the most potent antioxidant polyphenols associated with anti-atherogenic, antitumor and anti-mutagenic activities.

  10. Beneficial Effects of Oolong Tea Consumption on Diet-induced Overweight and Obese Subjects

    Institute of Scientific and Technical Information of China (English)

    HE Rong-rong; CHEN Ling; LIN Bing-hui; MATSUI Yokichi; YAO Xin-sheng; KURIHARA Hiroshi

    2009-01-01

    Objective: To determine the anti-obesity effects of oolong tea on diet-induced overweight or obesity. Methods: A total of 8 g of oolong tea a day for 6 weeks was ingested by 102 diet-induced overweight or obese subjects. The body fat level of the subjects was determined at the same time by taking body weight, height and waist measurements. The thickness of the subcutaneous fat layer was also determined on the abdomen 3 cm to the right of the navel by the ultrasonic echo method. On the other hand, effects of oolong tea ingestion on plasma triglyceride (TG) and total cholesterol (TC) were determined. Inhibitions of pancreatic lipase by oolong tea extract and catechins in vitro were also determined. Results: A total of 70% of the severely obese subjects did show a decrease of more than 1 kg in body weight, including 22% who lost more than 3 kg. Similarly, 64% of the obese subjects and 66% of the overweight subjects lost more than 1 kg during the experiment, and the subcutaneous fat content decreased in 12% of the subjects. The correlation between weight loss and subcutaneous fat decrease in men (r=0.055) was obviously lower than that in women (r=0.440, P0.05). Moreover, the plasma levels of TG and TC of the subjects with hyperlipidemia were remarkably decreased after ingesting oolong tea for 6 weeks. In vitro assays for the inhibition of pancreatic lipase by oolong tea extract and catechins suggest that the mechanism for oolong tea to prevent hyperlipidemia may be related to the regulative action of oolong tea catechins in lipoprotein activity. Conclusions: Oolong tea could decrease body fat content and reduce body weight through improving lipid metabolism. Chronic consumption of oolong tea may prevent against obesity.

  11. Flavan 3-ols improve metabolic syndrome risk factors: evidence and mechanisms.

    Science.gov (United States)

    Osakabe, Naomi

    2013-05-01

    Flavan 3-ols, a type of polyphenolic substance, are distributed in a number of plant foods. Of these foods, chocolate is very rich in flavan 3-ols as flavan 3-ol monomers, (+)-catechin and (-)-epicatechin, and the oligomers as procyanidins. There is evidence that cacao products containing flavan 3-ols have the potential to contribute to the risk reduction of cardiometabolic disorders according to recent epidemiological or intervention studies. This review focuses on recent advances in research on the ability of flavan 3-ols to reduce the risk of cardiovascular disease as a result of improving metabolic syndrome risk factors and these mechanisms. PMID:23704807

  12. Green tea extract for external anogenital warts.

    Science.gov (United States)

    2015-10-01

    Catephen (Kora Corporation Ltd) is a herbal medicinal product consisting predominantly of catechins (sinecatechins) extracted from Camellia sinensis (L.) O. Kuntze folium (green tea leaf) formulated as a topical preparation for the treatment of external genital and perianal warts (condylomata acuminata).(1) Marketing authorisation for an ointment containing 0.1g of green tea extract per gram (10%) was granted by the Medicines and Healthcare products Regulatory Agency (MHRA) under the mutual recognition procedure in February 2015.(2) Here, we consider the evidence for Catephen ointment in the management of external genital and perianal warts and its place within current management strategies. PMID:26471269

  13. Simultaneous metal adsorption on tannin resins

    International Nuclear Information System (INIS)

    Vegetable tannin sorbent is evaluated as ion exchange resin using a multitracer study on the adsorption behavior of various elements. Lisiloma latisiliqua L. tannins, polycondensated into spherical pellets were chosen as sorbent resin material. Sorption evaluation of Ce, Cu(II), U(VI), Eu, Fe(III), Th, Nd as representatives of different classes of metal ions were done at different pH values. The distribution ratio of the studied elements was calculated from laboratory experiments. Tannic ion exchange material shows excellent ability for actinides and rare earth elements adsorption from waters. Using radiotracers, the number of catechins subunits involve in each tannin-metal complex was determined. (author)

  14. Changes in Soluble-N in Forest and Pasture Soils after Repeated Applications of Tannins and Related Phenolic Compounds

    OpenAIRE

    Halvorson, Jonathan J.; Gonzalez, Javier M.; Hagerman, Ann E.

    2012-01-01

    Tannins (produced by plants) can reduce the solubility of soil-N. However, comparisons of tannins to related non-tannins on different land uses are limited. We extracted soluble-N from forest and pasture soils (0–5 cm) with repeated applications of water (Control) or solutions containing procyanidin from sorghum, catechin, tannic acid, β-1,2,3,4,6-penta-O-galloyl-D-glucose (PGG), gallic acid, or methyl gallate (10 mg g−1 soil). After eight treatments, samples were rinsed with cool water (23°C...

  15. Theagalloflavic Acid, a New Pigment Derived from Hexahydroxydiphenoyl Group, and Lignan Oxidation Products Produced by Aerobic Microbial Fermentation of Green Tea.

    Science.gov (United States)

    Matsuo, Yosuke; Matsuda, Tomoko; Sugihara, Keisuke; Saito, Yoshinori; Zhang, Ying-Jun; Yang, Chong-Ren; Tanaka, Takashi

    2016-01-01

    Chinese ripe pu-erh tea is produced by aerobic microbial fermentation of green tea. To clarify the microbial degradation of tea polyphenols, Japanese commercial green tea was mixed with Chinese ripe pu-erh tea, which retains microorganisms, and fermented for 5 d. Chromatographic separation yielded a novel water-soluble yellow pigment termed theagalloflavic acid. Spectroscopic and chemical evidence suggested that this pigment was produced by oxidative ring cleavage of hexahydroxydiphenoyl esters. In addition, two new oxygenated lignin metabolites, (+)-5,5'-dihydroxypinoresinol and 5-hydroxydihydrodehydrodiconiferyl alcohol, were also isolated together with known degradation products of quercetin and tea catechins. PMID:27373646

  16. Antioxidant capacities of ten edible North American plants.

    Science.gov (United States)

    Acuña, Ulyana Muñoz; Atha, Daniel E; Ma, Jun; Nee, Michael H; Kennelly, Edward J

    2002-02-01

    The EtOAc extract obtained from ten edible North American plants, Acorus calamus, Clintonia borealis, Gaultheria shallon, Juniperus osteosperma, Opuntia polyacantha, Prunus americana, Prunus virginiana, Sambucus cerulea, Sorbus americana and Vaccinium parvifolium, were tested in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical assay. High antioxidant activity was obtained from the extracts of three fruits, Gaultheria shallon, Sambucus cerulea and Prunus americana and one extracted rhizome, Acorus calamus. Catechin and epicatechin, potent polyphenolic antioxidants, were identified in the EtOAc extracts of Gaultheria shallon and Sambucus cerulea by reversed-phase thin-layer chromatography (TLC) and reversed-phase high-performance liquid chromatography (HPLC). PMID:11807968

  17. Green Tea Consumption after Intense Taekwondo Training Enhances Salivary Defense Factors and Antibacterial Capacity

    OpenAIRE

    Lin, Shiuan-Pey; Li, Chia-Yang; Suzuki, Katsuhiko; Chang, Chen-Kang; Chou, Kuei-Ming; Fang, Shih-Hua

    2014-01-01

    The aim of this study was to investigate the short-term effects of green tea consumption on selected salivary defense proteins, antibacterial capacity and anti-oxidation activity in taekwondo (TKD) athletes, following intensive training. Twenty-two TKD athletes performed a 2-hr TKD training session. After training, participants ingested green tea (T, caffeine 6 mg/kg and catechins 22 mg/kg) or an equal volume of water (W). Saliva samples were collected at three time points: before training (B...

  18. Camellia sinensis (Tea: Implications and role in preventing dental decay

    Directory of Open Access Journals (Sweden)

    Puneet Goenka

    2013-01-01

    Full Text Available Tea is one of the most commonly consumed beverages with bioactive compounds like polyphenols-flavonoids-catechins, which are thought to be responsible for the health benefits that have traditionally been attributed to the tea. These compounds have multi-dimensional effects such as antibacterial action, inhibitory action on the bacterial and salivary amylase and inhibition of acid production. This article outlines the possible role of these compounds coupled with the presence of high fluoride content in tea to exhibit an anticariogenic effect.

  19. Camellia sinensis (Tea): Implications and role in preventing dental decay.

    Science.gov (United States)

    Goenka, Puneet; Sarawgi, Aditi; Karun, Vinayak; Nigam, Anant G; Dutta, Samir; Marwah, Nikhil

    2013-07-01

    Tea is one of the most commonly consumed beverages with bioactive compounds like polyphenols-flavonoids-catechins, which are thought to be responsible for the health benefits that have traditionally been attributed to the tea. These compounds have multi-dimensional effects such as antibacterial action, inhibitory action on the bacterial and salivary amylase and inhibition of acid production. This article outlines the possible role of these compounds coupled with the presence of high fluoride content in tea to exhibit an anticariogenic effect. PMID:24347923

  20. Periodontal Disease-Induced Atherosclerosis and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Tomoko Kurita-Ochiai

    2015-09-01

    Full Text Available Periodontal disease is a highly prevalent disorder affecting up to 80% of the global population. Recent epidemiological studies have shown an association between periodontal disease and cardiovascular disease, as oxidative stress plays an important role in chronic inflammatory diseases such as periodontal disease and cardiovascular disease. In this review, we focus on the mechanisms by which periodontopathic bacteria cause chronic inflammation through the enhancement of oxidative stress and accelerate cardiovascular disease. Furthermore, we comment on the antioxidative activity of catechin in atherosclerosis accelerated by periodontitis.

  1. Effects of fisetin on mouse lipid metabolism in vitro and in vivo

    OpenAIRE

    Tomoaki Yonesaka; Kaoru Yoshida; Shunsuke Iizuka; Hiromi Hagiwara

    2014-01-01

    Objective: The aim of this study was to investigate the anti-obesity effects of the polyphenol fisetin in 3T3-L1 preadipocytes and C57BL/6 female mice that were fed a high-fat diet (HFD). Background: Polyphenols, such as sakuranetin, hesperetin, tea catechin, and quercetin, reportedly regulate adipocyte differentiation in 3T3-L1 cells. Furthermore, green tea, apple, and molokheiya polyphenols exhibit anti-obesity activities in HFD-treated obese rats or mice. Fisetin is abund...

  2. Analysis of Phenolic Compounds and Antioxidant Abilities of Extracts from Germinating Vitis californica Seeds Submitted to Cold Stress Conditions and Recovery after the Stress

    OpenAIRE

    Stanisław Weidner; Sebastian Chrzanowski; Magdalena Karamać; Angelika Król; Anna Badowiec; Agnieszka Mostek; Ryszard Amarowicz

    2014-01-01

    The material for this study consisted of stratified seeds of Vitis californica submitted to germination under optimum conditions (+25 °C) or under chill stress (+10 °C), also followed by recovery. It has been determined that the germinating seeds contain considerable amounts of tannins, catechins as well as phenolic acids such as gallic, p-coumaric, caffeic and ferulic acids. Gallic acid appeared in the highest amount in the germinating seeds (from 42.40–204.00 µg/g of fresh weight (FW)), fo...

  3. Bioactive triterpenes and phenolics of leaves of Eugenia brasiliensis

    International Nuclear Information System (INIS)

    A chemical investigation of Eugenia brasiliensis Lam. (Myrtaceae) leaves led to the isolation of β-amyrin and b-amyrin (in a mixture), betulin, 29-hydroxy-oleanolic acid, quercetin, catechin and gallocatechin. Herein, the identification of 29-hydroxy-oleanolic acid is reported for the first time in the Myrtaceae family. Moreover, in this study, the extract, fractions and six of the seven compounds were monitored for toxicity toward Artemia salina, antibacterial and acetylcholinesterase inhibitory activity. The crude ethanol extract of the leaves and fractions were found be active on A. salina toxicity bioassay (author)

  4. Neuroprotective effects of berry fruits on neurodegenerative diseases

    Institute of Scientific and Technical Information of China (English)

    Selvaraju Subash; Musthafa Mohamed Essa; Samir Al-Adawi; Mushtaq A.Memon; hTamilarasan Manivasagam; Mohammed Akbar

    2014-01-01

    Recent clinical research has demonstrated that berry fruits can prevent age-related neurodegen-erative diseases and improve motor and cognitive functions. The berry fruits are also capable of modulating signaling pathways involved in inflammation, cell survival, neurotransmission and enhancing neuroplasticity. The neuroprotective effects of berry fruits on neurodegenerative diseases are related to phytochemicals such as anthocyanin, caffeic acid, catechin, quercetin, kae-mpferol and tannin. In this review, we made an attempt to clearly describe the beneifcial effects of various types of berries as promising neuroprotective agents.

  5. Enriquecimento de compostos fenólicos de folhas de Inga edulis por extração em fase sólida: quantificação de seus compostos majoritários e avaliação da capacidade antioxidante Purification of phenolic compounds from Inga edulis leaves using solid-phase extraction: major compounds quantification and antioxidant capacity evaluation

    Directory of Open Access Journals (Sweden)

    Aécio Luís de Sousa Dias

    2010-01-01

    Full Text Available A phenolic fraction was obtained from of the acetone-water-acetic acid extract of Inga edulis leaves, by liquid-liquid partition and SPE-C18 cartridges. This method provided an increase of 108, 66, 51, 50 and 36% of flavonols, proanthocyanidins, total polyphenols, gallotannins and flavanols, respectively. The major phenolics in purified fraction were procyanidin B2, catechin and myricetin-3-O-α-L-rhamnopyranoside, which achieved increases of 111, 47 and 45%, respectively, after SPE. Acid hydrolysis confirmed the presence of procyanidins, prodelphinidins and glycosylated flavonoids.

  6. Epigallocatechin-3-gallate Inhibits LPS-Induced NF-κB and MAPK Signaling Pathways in Bone Marrow-Derived Macrophages

    OpenAIRE

    Joo, So-Young; Song, Young-A; Park, Young-Lan; Myung, Eun; Chung, Cho-Yun; Park, Kang-Jin; Cho, Sung-Bum; Lee, Wan-Sik; Kim, Hyun-Soo; Rew, Jong-Sun; Kim, Nack-Sung; Joo, Young-Eun

    2012-01-01

    Background/Aims Epigallocatechin-3-gallate (EGCG), the primary catechin in green tea, has anti-inflammatory and anti-oxidative properties. The aim of the current study was to characterize the impact of EGCG on lipopolysaccharide (LPS)-induced innate signaling in bone marrow-derived macrophages (BMMs) isolated from ICR mice. Methods The effect of EGCG on LPS-induced pro-inflammatory gene expression and nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling was examined...

  7. Analysis of commercial proanthocyanidins. Part 3: the chemical composition of wattle (Acacia mearnsii) bark extract.

    Science.gov (United States)

    Venter, Pieter B; Senekal, Nadine D; Kemp, Gabré; Amra-Jordaan, Maryam; Khan, Pir; Bonnet, Susan L; van der Westhuizen, Jan H

    2012-11-01

    Wattle (Acacia mearnsii) bark extract is an important renewable industrial source of natural polymers for leather tanning and adhesive manufacturing. The wattle bark proanthocyanidin oligomers have 5-deoxy extender units that render the interflavanyl bonds resistant to acid catalysed hydrolysis and their composition cannot be determined via conventional thiolysis. We combined established phyto- and synthetic chemistry perspectives with an electrospray mass spectrometry investigation to establish that the flavan-3-ol based oligomers consist of a starter unit which is either catechin or gallocatechin, angularly bonded to fisetinidol or predominantly robinetinidol extender units. PMID:22917955

  8. Effects of Flavonoids on Rumen Fermentation Activity, Methane Production, and Microbial Population

    OpenAIRE

    Ehsan Oskoueian; Norhani Abdullah; Armin Oskoueian

    2013-01-01

    This research was carried out to evaluate the effects of flavone, myricetin, naringin, catechin, rutin, quercetin, and kaempferol at the concentration of 4.5% of the substrate (dry matter basis) on the rumen microbial activity in vitro. Mixture of guinea grass and concentrate (60 : 40) was used as the substrate. The results showed that all the flavonoids except naringin and quercetin significantly (P < 0.05) decreased the dry matter degradability. The gas production significantly (P < 0.05) d...

  9. Analysis of cream formation in green tea concentrates with different solid concentrations

    OpenAIRE

    Xu, Yong-Quan; Chen, Su-Qin; Yuan, Hai-Bo; Tang, Ping; Yin, Jun-Feng

    2011-01-01

    The formation of tea cream in the green tea concentrates of different solid concentrations (5, 10, 20, 30, 40, 50 and 60°Brix) was investigated. The results showed a good positive correlation (γ = 0.98, p ≤ 0.05) between the amount of tea cream and the solid concentrations from 5 to 40°Brix, while the amount of tea cream in the tea concentrates of 50 and 60°Brix decreased acutely. Total sugar, caffeine and catechins were found to be the main chemical components of tea cream in the green tea c...

  10. Health-promoting effects of green tea

    OpenAIRE

    Suzuki, Yasuo; Miyoshi, Noriyuki; ISEMURA, Mamoru

    2012-01-01

    Green tea is manufactured from the leaves of the plant Camellia sinensis Theaceae and has been regarded to possess anti-cancer, anti-obesity, anti-atherosclerotic, anti-diabetic, anti-bacterial, and anti-viral effects. Many of the beneficial effects of green tea are related to the activities of (−)-epigallocatechin gallate (EGCG), a major component of green tea catechins. For about 20 years, we have engaged in studies to reveal the biological activities and action mechanisms of green tea and ...

  11. Antioxidant and antiviral properties of Pseudopiptadenia contorta (Leguminosae and of quebracho (Schinopsis sp. extracts

    Directory of Open Access Journals (Sweden)

    Davyson de L. Moreira

    2005-06-01

    Full Text Available Proanthocyanidins from P. contorta leaves and from a commercial quebracho extract were isolated and characterized. Flavonoids, catechins and gallic acid were also identified in the extracts of P. contorta. Compounds were evaluated for their antioxidant properties and for their antiviral activity against an acyclovir-resistant herpes simplex virus type 1 strain. The low molecular weight phenolic derivatives and the proanthocyanidins from P. contorta showed the highest antioxidant activity. Purified proanthocyanidins from both P. contorta and quebracho showed the same maximum non toxic concentrations (25 µg/mL, with 82.2% and 100% of virus inhibition, respectively.

  12. Free radical scavenging activity of Eagle tea and their flavonoids

    Directory of Open Access Journals (Sweden)

    Qiong Meng

    2012-06-01

    Full Text Available In this study, an online HPLC-DAD-MS coupled with 2,2′-azinobis (3-ethylbenzthiazoline-6-sulfonic acid diammonium salt (ABTS assay was employed for evaluating free radical scavenging activity of Eagle tea and their active components. Twenty-three chromatographic peaks were detected, and nineteen components had free radical scavenging activity. Among them, eight compounds were identified as flavonoids (hyperin, isoquercitrin, quercitrin, quercetin, kaempferol, catechins, chlorogenic acid and epicatechin based on MS data and standard chromatographic characters.

  13. Dietary A- and B-type procyanidins : characterization and biofunctional potential of an abundant and diverse group of phenolics

    OpenAIRE

    Appeldoorn, M.M.

    2009-01-01

    Procyanidins (PCs) are phenolic compounds that belong to the class of flavonoids and are oligomers of monomeric (epi)catechin units. These monomeric units can be linked to each other by a single C4-C8 or C4-C6 linkage, which is referred to as B-type. Besides these single linkages an additional ether bond can be present, C2-O-C7 or C2-O-C5, which is referred to as A-type. PCs are highly abundant in our diet. Well known PC food sources are cocoa, apple, grape seeds, wine and nuts. After the int...

  14. Protective effects of (-)-epigallocatechin-3-gallate against acetaminophen-induced liver injury in rats)

    OpenAIRE

    Yao, Hsien-Tsung; Yang, Yu-Chi; Chang, Chen-Hui; Yang, Hui-Ting; Yin, Mei-chin

    2015-01-01

    (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin with various biological activities found in tea. In this study, the effects of EGCG on the metabolism and toxicity of acetaminophen in rat liver were investigated. Male Sprague-Dawley rats were fed a controlled diet without or with EGCG (0.54 %, w/w) for 1 week and were then intraperitoneally injected with acetaminophen (1 g/kg body weight) and killed after 12 h. Concentrations of acetaminophen and its conjugates in plasma an...

  15. Solid grape extract for protection against the sun consists of a residues based material containing gallic acid flavonol and e.g. procyanidine

    OpenAIRE

    Torres, Josep Lluís; González, Pedro; Cascante, Marta; Comín, Begoña

    2001-01-01

    [EN]The solid grape extract for protection against the sun comprises a residues-based material containing gallic acid 1-5, flavonol and its glycosyl derivatives 1-20 and catechin and its oligomers or procyanidine 1-30 per cent respectively. The grape residue is extracted by aqueous ethanol with lyophilisation and suspension in water. The polyphenolic fraction is extracted in ethyl acetate for suspension in water, centrifugation and lyophilisation. [ES]Extracto de uva para protección solar. Se...

  16. Chemical constituents of Phragmanthera austroarabica A. G. Mill and J. A. Nyberg with potent antioxidant activity

    Directory of Open Access Journals (Sweden)

    Jihan M Badr

    2015-01-01

    Full Text Available Background: Phragmanthera austroarabica A.G. Mill. and J. A. Nyberg is a semi parasitic plant belonging to family Loranthaceae. It was collected from Saudi Arabia. It is widely used in folk medicine among the kingdom in treatment of various diseases including diabetes mellitus. Objective: The total alcoholic extract of P. austroarabica collected from Saudi Arabia was investigated for the chemical structure and prominent biological activity of the main constituents. Materials and Methods: Isolation of the active constituents was performed using different chromatographic techniques including column chromatography packed with silica or sephadex and preparative thin layer chromatography. The structures of the isolated compounds were established based on different spectroscopic data as mass spectrum, one-dimensional and two-dimensional nuclear magnetic resonance (correlation spectroscopy, heteronuclear single quantum coherence, and heteronuclear multiple-bond correlation. Results: Phytochemical investigation of the plant resulted in isolation of 12 compounds. The isolated compounds were identified as chrysophanic acid, emodin, chrysophanic acid-8-O-glucoside, emodin-8-O-glucoside, pectolinarigenin, quercetin, dillenetin-3-O-glucoside, catechin, catechin-4′-O-gallate, methyl gallate, lupeol and ursolic acid. All the isolated phenolic compounds revealed significant free radical scavenging activities when tested using 2,2-diphenyl-1-picrylhydrazyl reagent. Conclusion: The antioxidant activities of the isolated compounds can justify the use of P. austroarabica in traditional medicine for treatment of diabetes and verify its possible application as an antihyperglycemic drug.

  17. Determination of Phenolic Content in Different Barley Varieties and Corresponding Malts by Liquid Chromatography-diode Array Detection-Electrospray Ionization Tandem Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Daniel O. Carvalho

    2015-08-01

    Full Text Available A simple and reliable method for the simultaneous determination of nine phenolic compounds in barley and malted barley was established, using liquid chromatography-diode array detection-electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MS/MS. The phenolic compounds can be easily detected with both systems, despite significant differences in sensitivity. Concentrations approximately 180-fold lower could be achieved by mass spectrometry analysis compared to diode array detection, especially for the flavan-3-ols (+-catechin and (−-epicatechin, which have poor absorptivity in the UV region. Malt samples were characterized by higher phenolic content comparing to corresponding barley varieties, revealing a significant increase of the levels of (+-catechin and (−-epicatechin during the malting process. Moreover, the industrial malting is responsible for modification on the phenolic profile from barley to malt, namely on the synthesis or release of sinapinic acid and epicatechin. Accordingly, the selection of the malting parameters, as well as the barley variety plays an important role when considering the quality and antioxidant stability of beer.

  18. Chemical Composition and Bioactivities of Two Common Chaenomeles Fruits in China: Chaenomeles speciosa and Chaenomeles sinensis.

    Science.gov (United States)

    Miao, Jing; Zhao, Chengcheng; Li, Xia; Chen, Xuetao; Mao, Xinhui; Huang, Hanhan; Wang, Tingting; Gao, Wenyuan

    2016-08-01

    Contents of total flavonoids, total phenolics, total triterpenes, total condensed tannin and total saponins in peels, flesh and endocarps of Chaenomeles speciosa (CSP) and Chaenomeles sinensis (CSS) were determined by colorimetric method, while 5 phenolics (vanillic, gallic, chlorogenic, ferulic and p-coumaric acids), 2 triterpenes (oleanolic and ursolic acids), and 3 flavonoids (rutin, catechin and epicatechin) were identified and quantified by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and HPLC, and antioxidant and α-glucosidase inhibitory activities of them also were evaluated as well as their digestive characteristics. In the correlation analysis, total phenolics, vanillic acid, catechin, ursolic acid and oleanolic acid all contribute to DPPH(·) scavenge capacity, gallic acid contributes to total ferric reducing antioxidant power, while total triterpenes, total saponins, chlorogenic acid and ferullic acid contribute to α-glucosidase inhibitory activity. In the principal component analysis, endocarps of CSP and CSS both show better quality than their peels and flesh, respectively. In vitro digestion can increase contents of total flavonoids, total condensed tannin and total saponins, while contents of total phenolics and total triterpenes decreased greatly. Our study would contribute to the full use of discarded parts of the 2 Chaenomeles and be helpful to establish a good foundation for further research of CSP and CSS. PMID:27384225

  19. THE INFLUENCE OF TIME AND TYPE OF SOLVENT ON EFFICIENCY OF THE EXTRACTION OF POLYPHENOLS FROM GREEN TEA AND ANTIOXIDANT PROPERTIES OBTAINED EXTRACTS

    Directory of Open Access Journals (Sweden)

    Beata Drużyńska

    2007-03-01

    Full Text Available The aim of the study was to investigate the influence of the type of solvent and time on efficiency of the extraction of polyphenols and antioxidant properties extracts obtained from green tea. Extraction was conducted at room temperature using four solvents: water and 80% ethanol, 80% methanol and 80% acetone (water solutions, v/v at 15, 30 and 60 minutes. Extracts were analysed for contents of polyphenols and catechins. The antioxidant properties have been determined by two methods: scavenging activity against DPPH· and the method with ABTS·+. The abilities of extracts to chelate iron ions (II have been investigated too. On the basis of findings it turned out that both type of solvent and time have a significant influence on extraction of polyphenols from green tea. The best solvent for the extraction of total polyphenols was 80% acetone, whereas for catechins was water. The increase of extraction of polyphenols with prolonged extraction time was observed. All extracts had antioxidant properties against DPPH· and ABTS·+ and abilities to chelate iron ions (II.

  20. Validation of AN Hplc-Dad Method for the Classification of Green Teas

    Science.gov (United States)

    Yu, Jingbo; Ye, Nengsheng; Gu, Xuexin; Liu, Ni

    A reversed phase high performance liquid chromatography (RP-HPLC) separation coupled with diode array detection (DAD) and electrospray ionization mass spectrometer (ESI/MS) was developed and optimized for the classification of green teas. Five catechins [epigallocatechin (EGC), epigallocatechin gallate (EGCG), epicatechin (EC), gallocatechin gallate (GCG), epicatechin gallate (ECG)] had been identified and quantified by the HPLC-DAD-ESI/MS/MS method. The limit of detection (LOD) of five catechins was within the range of 1.25-15 ng. All the analytes exhibited good linearity up to 2500 ng. These compounds were considered as chemical descriptors to define groups of green teas. Chemometric methods including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied for the purpose. Twelve green tea samples originating from different regions were subjected to reveal the natural groups. The results showed that the analyzed green teas were differentiated mainly by provenance; HCA afforded an excellent performance in terms of recognition and prediction abilities. This method was accurate and reproducible, providing a potential approach for authentication of green teas.

  1. Mixture design analysis of solvent extractor effects on epicatechin, epigallocatechin gallate, epigallocatechin and antioxidant activities of the Camellia sinensis L. leaves

    Directory of Open Access Journals (Sweden)

    Elis Daiane Pauli

    2014-11-01

    Full Text Available This paper reports an RP-HPLC-UV-DAD study of the effects of four solvents and their mixtures on the extraction and antioxidant activities of three main catechins, epicatechin (EC, epigallocatechin gallate (EGCG and epigallocatechin (EGC of Camellia sinensis L. leaves for two harvests. The extraction efficiency solvent was measured by the chromatographic peak areas. The results showed that the relative abundance of the catechins in the second harvest is somewhat larger than in the first one, although there is no significant difference at the 95% level. The relative abundance found for EGCG is greater than for EGC which is greater than EC for all solvent mixtures. According to the mixture models, the maximum values of relative abundances of EGCG, EGC and EC can be obtained with a (70:30 v/v ethanol:ethyl acetate binary mixture and the antioxidant activities with a (55:25:20 v/v/v ethanol:ethyl acetate:dichloromethane ternary mixture.

  2. Determination of antioxidant capacity and phenolic content of chocolate by attenuated total reflectance-Fourier transformed-infrared spectroscopy.

    Science.gov (United States)

    Hu, Yaxi; Pan, Zhi Jie; Liao, Wen; Li, Jiaqi; Gruget, Pierre; Kitts, David D; Lu, Xiaonan

    2016-07-01

    Antioxidant capacity and phenolic content of chocolate, containing different amounts of cacao (35-100%), were determined using attenuated total reflectance (ATR)-Fourier transformed-infrared (FT-IR) spectroscopy (4000-550cm(-1)). Antioxidant capacities were first characterized using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (oxygen radical absorbance capacity) assays. Phenolic contents, including total phenol and procyanidins monomers, were quantified using the Folin-Ciocalteu assay and high performance liquid chromatography coupled with photodiode array detector (HPLC-DAD), respectively. Five partial least-squares regression (PLSR) models were constructed and cross-validated using FT-IR spectra from 18 types of chocolate and corresponding reference values determined using DPPH, ORAC, Folin-Ciocalteu, and HPLC assays. The models were validated using seven unknown samples of chocolate. PLSR models showed good prediction capability for DPPH [R(2)-P (prediction)=0.88, RMSEP (root mean squares error of prediction)=12.62μmol Trolox/g DFW], ORAC (R(2)-P=0.90, RMSEP=37.92), Folin-Ciocalteu (R(2)-P=0.88, RMSEP=5.08), and (+)-catechin (R(2)-P=0.86, RMSEP=0.10), but lacked accuracy in the prediction of (-)-epicatechin (R(2)-P=0.72, RMSEP=0.57). ATR-FT-IR spectroscopy can be used for rapid prediction of antioxidant capacity, total phenolic content, and (+)-catechin in chocolate. PMID:26920292

  3. Altered Redox Status in Erythrocytes From Hypertensive Subjects: Effect of (-)Epicatechin

    Institute of Scientific and Technical Information of China (English)

    SYED IBRAHIM RIZVI; NAVNEET KUMAR

    2005-01-01

    Hypertension is a major problem worldwide. There is much evidence to suggest that reactive oxygen species (ROS) radical may play a role in the development of organ damage associated with cardiovascular disease and hypertension. (-)Epicatechin, a member of tea catechins belonging to flavonoid group, is known to be a potent anti-oxidant.The study has been undertaken to evaluate the effect of (-)epicatechin on markers of oxidative stress: reduced glutathione (GSH) and membrane sulfhydryl (-SH) groups in erythrocytes from hypertensive patients. The effect of (-)epicatechin was also compared with a known anti-oxidant L-ascorbic acid. The erythrocyte intracellular GSH content and membrane -SH group content were significantly (P<0.01) decreased in hypertensive subjects. In vitro incubation with (-)epicatechin caused an increase in GSH and -SH content, the effect was more pronounced in hypertensive erythrocytes. Similar results were obtained with L-ascorbic acid. The observed decrease in the level of GSH and -SH groups in hypertension is an indicator of oxidative stress condition. Observation of an increase in red cell GSH content and the protection of membrane -SH group oxidation by (-)epicatechin in hypertensive subjects is a convincing reason to suggest that high dietary intake of foods rich in catechins may help to reduce oxidative stress and concomitant free radical damage in hypertensive patients.

  4. Pharmaceutical and nutraceutical effects of Pinus pinaster bark extract.

    Science.gov (United States)

    Iravani, S; Zolfaghari, B

    2011-01-01

    In everyday life, our body generates free radicals and other reactive oxygen species which are derived either from the endogenous metabolic processes (within the body) or from external sources. Many clinical and pharmacological studies suggest that natural antioxidants can prevent oxidative damage. Among the natural antioxidant products, Pycnogenol(®) (French Pinus pinaster bark extract) has been received considerable attention because of its strong free radical-scavenging activity against reactive oxygen and nitrogen species. P. pinaster bark extract (PBE) contains polyphenolic compounds (these compounds consist of catechin, taxifolin, procyanidins of various chain lengths formed by catechin and epicatechin units, and phenolic acids) capable of producing diverse potentially protective effects against chronic and degenerative diseases. This herbal medication has been reported to have cardiovascular benefits, such as vasorelaxant activity, angiotensin-converting enzyme inhibiting activity, and the ability to enhance the microcirculation by increasing capillary permeability. Moreover, effects on the immune system and modulation of nitrogen monoxide metabolism have been reported. This article provides a brief overview of clinical studies describing the beneficial and health-promoting effects of PBE. PMID:22049273

  5. A comparative study of size-controlled worm-like amylopectin nanoparticles and spherical amylose nanoparticles: Their characteristics and the adsorption properties of polyphenols.

    Science.gov (United States)

    Qiu, Chao; Qin, Yang; Zhang, Shuangling; Xiong, Liu; Sun, Qingjie

    2016-12-15

    Polyphenols are known to have potent antioxidant capacity and other health-beneficial bioactivities. However, extremely low absorption rate of polyphenols restricts their bioactivity in vivo. Development of biopolymer nanoparticle carrier is a promising solution. For the first time, we have successfully prepared worm-like amylopectin nanoparticles (APNPs) and spherical amylose nanoparticles (AMNPs) using fractionated amylose and amylopectin from potato starch. Additionally, adsorption kinetics and adsorption isotherms of three polyphenols (procyanidins, epicatechins and catechins) on AMNPs and APNPs were investigated. We found that procyanidins, epicatechins, and catechins could bind to AMNPs at levels of up to 1.2, 1.5, and 1.4g/g, respectively, while the APNPs demonstrated higher adsorption amounts of 1.4, 4.3, and 2.2g/g, respectively. Furthermore, the particle size of polyphenol-loaded nanoparticles was not significantly changed. The results suggested that APNPs and AMNPs can be applied as an effective nanocarrier by delivering active compounds for nutraceutical and pharmaceutical industries. PMID:27451221

  6. Chemistry of Secondary Polyphenols Produced during Processing of Tea and Selected Foods

    Directory of Open Access Journals (Sweden)

    Takashi Tanaka

    2009-12-01

    Full Text Available This review will discuss recent progress in the chemistry of secondary polyphenols produced during food processing. The production mechanism of the secondary polyphenols in black tea, whisky, cinnamon, and persimmon fruits will be introduced. In the process of black tea production, tea leaf catechins are enzymatically oxidized to yield a complex mixture of oxidation products, including theaflavins and thearubigins. Despite the importance of the beverage, most of the chemical constituents have not yet been confirmed due to the complexity of the mixture. However, the reaction mechanisms at the initial stages of catechin oxidation are explained by simple quinone–phenol coupling reactions. In vitro model experiments indicated the presence of interesting regio- and stereoselective reactions. Recent results on the reaction mechanisms will be introduced. During the aging of whisky in oak wood barrels, ellagitannins originating from oak wood are oxidized and react with ethanol to give characteristic secondary ellagitannins. The major part of the cinnamon procyanidins is polymerized by copolymerization with cinnamaldehyde. In addition, anthocyanidin structural units are generated in the polymer molecules by oxidation which accounts for the reddish coloration of the cinnamon extract. This reaction is related to the insolubilization of proanthocyanidins in persimmon fruits by condensation with acetaldehyde. In addition to oxidation, the reaction of polyphenols with aldehydes may be important in food processing.

  7. Methods for Extraction and Charaterization of Tannins from Some Acacia Species of Sudan

    Directory of Open Access Journals (Sweden)

    Isam Eldin Hussein Elgailani

    2016-06-01

    Full Text Available The study is aimed to analyze and compare extraction methods of tannins from three common Acacia species of Sudan. The Acacia species selected were Acacia nilotica, Acacia seyal and Acacia senegal. Bark samples from bulk collections of the three Acacia species were extracted with water, 80% methanol and 70% acetone. Two sets of extraction were made, one by boiling and a second by shaking the samples in the respective solvents for eight hours at room temperature. Although the amount of material extracted by these two procedures did not differ greatly (P > 0.05, 70% acetone was a more efficient solvent than either water or 80% methanol. The tannins of mature fruits extract of Acacia nilotica were identified by using Thin Layer Chromatography (TLC, Ultraviolet and Infrared spectroscopy. Comparisons of absorption spectra and TLC of the reference tannins and some phenolics with that of Acacia nilotica extracts revealed the presence of both condensed and hydrolyzable tannins, since it consists of catechin, tannic and gallic acids. Catechin considered to be the phenolic precursor of condensed tannins. Hydrolysis of Acacia nilotica extract, tannic and gallic acids by butanolic-hydrochloric acid yielded gallic acid which is considered to be a chemical precursor of hydrolyzable tannins

  8. Cytoprotective Effects of Hydrophilic and Lipophilic Extracts of Pistacia vera against Oxidative Versus Carbonyl Stress in Rat Hepatocytes.

    Science.gov (United States)

    Shahraki, Jafar; Zareh, Mona; Kamalinejad, Mohammad; Pourahmad, Jalal

    2014-01-01

    This study was conducted to evaluate the cytoprotection of various extracts and bioactive compounds found in Pistacia vera againts cytotoxicity, ROS formation, lipid peroxidation, protein carbonylation, mitochondrial and lysosomal membrane damages in cell toxicity models of diabetes related carbonyl (glyoxal) and oxidative stress (hydroperoxide). Methanol, water and ethyl acetate were used to prepare crude pistachios extracts, which were then used to screen for in-vitro cytoprotection of freshly isolated rat hepatocytes against these toxins. The order of protection by Pistacia vera extracts against both hydroperoxide induced oxidative stress (ROS formation) and glyoxal induced protein carbonylation was: pistachio methanolic extract >pistachio water extract, gallic acid, catechin> α-tochoferol and pistachio ethyl acetate extract. Finally due to higher protection achieved by methanolic extract even compared to sole pretreatment of gallic acid, catechin or α-tochoferol, we suggest that cytoprotection depends on the variety of polar and non-polar compounds found in methanolic extract, it is likely that multiple cytoprotective mechanisms are acting against oxidative and carbonyl induced cytotoxicity. To our knowledge, we are the first to report the cytoprotective activity of Pistacia vera extracts against oxidative and carbonyl stress seen in type 2 diabetes hepatocytes model. PMID:25587316

  9. Determination of phenolic compounds using spectral and color transitions of rhodium nanoparticles.

    Science.gov (United States)

    Gatselou, Vasiliki; Christodouleas, Dionysios C; Kouloumpis, Antonios; Gournis, Dimitrios; Giokas, Dimosthenis L

    2016-08-17

    This work reports a new approach for the determination of phenolic compounds based on their interaction with citrate-capped rhodium nanoparticles. Phenolic compounds (i.e., catechins, gallates, cinnamates, and dihydroxybenzoic acids) were found to cause changes in the size and localized surface plasmon resonance of rhodium nanoparticles, and therefore, give rise to analyte-specific spectral and color transitions in the rhodium nanoparticle suspensions. Upon reaction with phenolic compounds (mainly dithydroxybenzoate derivatives, and trihydroxybenzoate derivatives), new absorbance peaks at 350 nm and 450 nm were observed. Upon reaction with trihydroxybenzoate derivatives, however, an additional absorbance peak at 580 nm was observed facilitating the speciation of phenolic compounds in the sample. Both absorbance peaks at 450 nm and 580 nm increased with increasing concentration of phenolic compounds over a linear range of 0-500 μM. Detection limits at the mid-micromolar levels were achieved, depending on the phenolic compound involved, and with satisfactory reproducibility (phenolic content and total catechin content were developed and applied in tea samples. The obtained results correlated favorably with commonly used methods (i.e., Folin-Ciocalteu and aluminum complexation assay). Not the least, the finding that rhodium nanoparticles can react with analytes and exhibit unique localized surface plasmon resonance bands in the visible region, can open new opportunities for developing new optical and sensing analytical applications. PMID:27286772

  10. Spin Trapping Radicals from Lipid Oxidation in Liposomes in the Presence of Flavonoids

    International Nuclear Information System (INIS)

    Interactions of four structurally related flavonoids - quercetin, rutin, morin and catechin with peroxyl radicals using liposome/N-tert-butyl-alpha-phenylnitrone (PBN) and liposome -(4-pyridyl-N-oxide)-N-tert-butylnitrone (POBN)-spin trap systems have been studied through spin trapping ESR. Results obtained were different from that of conjugated diene analysis experiments, where lag phases indicated radical scavenging activity of all the flavonoids. No clear lag phase was observed in ESR experiments under same conditions. In the presence of flavonoids decreasing ESR signals of spin adducts in PBN, while no or negligibly smaller spin adducts with POBN system were observed which may be attributed to the possibility that spin traps interacted with free radicals. Experiments with buffer/spin trap systems without liposome revealed that spin adducts were only stable with catechin and destroyed by quercetin, rutin and morin in buffer/spin trap systems. These results further assured that quercetin, rutin and morin not only interacted with peroxyl radicals but also with spin adducts. (author)

  11. Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

    International Nuclear Information System (INIS)

    Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

  12. Effects of (−-Gallocatechin-3-Gallate on Tetrodotoxin-Resistant Voltage-Gated Sodium Channels in Rat Dorsal Root Ganglion Neurons

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    Jian-Min Jiang

    2013-05-01

    Full Text Available The (−-gallocatechin-3-gallate (GCG concentration in some tea beverages can account for as much as 50% of the total catechins. It has been shown that catechins have analgesic properties. Voltage-gated sodium channels (Nav mediate neuronal action potentials. Tetrodotoxin inhibits all Nav isoforms, but Nav1.8 and Nav1.9 are relatively tetrodotoxin-resistant compared to other isoforms and functionally linked to nociception. In this study, the effects of GCG on tetrodotoxin-resistant Na+ currents were investigated in rat primary cultures of dorsal root ganglion neurons via the whole-cell patch-clamp technique. We found that 1 μM GCG reduced the amplitudes of peak current density of tetrodotoxin-resistant Na+ currents significantly. Furthermore, the inhibition was accompanied by a depolarizing shift of the activation voltage and a hyperpolarizing shift of steady-state inactivation voltage. The percentage block of GCG (1 μM on tetrodotoxin-resistant Na+ current was 45.1% ± 1.1% in 10 min. In addition, GCG did not produce frequency-dependent block of tetrodotoxin-resistant Na+ currents at stimulation frequencies of 1 Hz, 2 Hz and 5 Hz. On the basis of these findings, we propose that GCG may be a potential analgesic agent.

  13. Anti-allergic effects of ethanol extracts from brown seaweeds

    Institute of Scientific and Technical Information of China (English)

    Haider SAMEE; Zhen-xing LI; Hong LIN; Jamil KHALID; Yong-chao GUO

    2009-01-01

    Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities.They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan,and Sargassum graminifolium turn (SG),Sargassum thunbergii (STH),and Laminariajaponica (LJ) from China.The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin,an inhibitor against hyaluronidase.Total phlorotannins contained in the crude extracts were measured as 1.71% (SG),0.74% (STH),0.97% (LJ),3.30% (SC),and 5.06% (ST).The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml,respectively,lower than those of Chinese SG,STH,and LJ (134,269,and 148 μg/ml,respectively).An antiallergic drug,disodium cromoglycate (DSCG),had an IC50=39 μg/ml,and a natural inhibitor of hyaluronidase,catechin,had an IC50=20 μg/ml.The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml).This suggests that ST is a potent inhibitor of hyaluronidase,indicating a promising future development of natural antiallergic medicines or functional foods.

  14. Anti-allergic effects of ethanol extracts from brown seaweeds*

    Science.gov (United States)

    Samee, Haider; Li, Zhen-xing; Lin, Hong; Khalid, Jamil; Guo, Yong-chao

    2009-01-01

    Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum graminifolium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods. PMID:19235274

  15. Anti-allergic effects of ethanol extracts from brown seaweeds.

    Science.gov (United States)

    Samee, Haider; Li, Zhen-xing; Lin, Hong; Khalid, Jamil; Guo, Yong-chao

    2009-02-01

    Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum graminifolium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC(50)) of Pakistani SC and ST were 109.5 and 21 microg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 microg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC(50)=39 microg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC(50)=20 microg/ml. The IC(50) of ST extract was found similar to that of catechin (21 vs 20 microg/ml) and lower than that of DSCG (21 vs 39 microg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods. PMID:19235274

  16. Combinatorial Activity of Flavonoids with Antibiotics Against Drug-Resistant Staphylococcus aureus.

    Science.gov (United States)

    Abreu, Ana Cristina; Serra, Sofia C; Borges, Anabela; Saavedra, Maria José; Mcbain, Andrew J; Salgado, António J; Simões, Manuel

    2015-12-01

    The use of resistance-modifying agents is a potential strategy that is used to prolong the effective life of antibiotics in the face of increasing antibiotic resistance. Since certain flavonoids are potent bacterial efflux pump inhibitors, we assessed morin, rutin, quercetin, hesperidin, and (+)-catechin for their combined activity with the antibiotics ciprofloxacin, tetracycline, erythromycin, oxacillin, and ampicillin against drug-resistant strains of Staphylococcus aureus, including methicillin-resistant S. aureus. Four established methods were used to determine the combined efficacy of each combination: microdilution checkerboard assays, time-kill determinations, the Etest, and dual disc-diffusion methods. The cytotoxicity of the flavonoids was additionally evaluated in a mouse fibroblast cell line. Quercetin and its isomer morin decreased by 3- to 16-fold the minimal inhibitory concentration of ciprofloxacin, tetracycline, and erythromycin against some S. aureus strains. Rutin, hesperidin, and (+)-catechin did not promote any potentiation of antibiotics. Despite the potential cytotoxicity of these phytochemicals at a high concentration (fibroblast IC50 of 41.8 and 67.5 mg/L, respectively), quercetin is commonly used as a supplement for several therapeutic purposes. All the methods, with exception of the time-kill assay, presented a high degree of congruence without any apparent strain specificity. PMID:25734256

  17. Effect of Brewing Duration on the Antioxidant and Hepatoprotective Abilities of Tea Phenolic and Alkaloid Compounds in a t-BHP Oxidative Stress-Induced Rat Hepatocyte Model

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    Laura Braud

    2015-08-01

    Full Text Available Tea is an interesting source of antioxidants capable of counteracting the oxidative stress implicated in liver diseases. We investigated the impact of antioxidant molecules provided by a mixture of teas’ leaves (green, oolong, pu-erh after different infusion durations in the prevention of oxidative stress in isolated rat hepatocytes, by comparison with pure epigallocatechin-3-gallate (EGCG, the main representative of tea catechins. Dried aqueous tea extracts (ATE obtained after 5, 15 and 30 min infusion time were characterized for total polyphenols (gallic acid equivalent, catechins, gallic acid and caffeine (HPLC-DAD/ESI-MS contents, and for scavenging ability against 2,2-diphenyl-1-picrylhydrazyl free radical. Hepatoprotection was evaluated through hepatocyte viability tests using tert-butyl hydroperoxide as a stress inducer, (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, neutral red uptake, real-time cellular impedance and mitochondrial function tests. We showed that a 5-min incubation time is sufficient for an optimal bioaccessibility of tea compounds with the highest antioxidative ability, which decreases for longer durations. A 4-h pretreatment of cells with ATE significantly prevented cell death by regulating reactive oxygen species production and maintaining mitochondrial integrity. Pure EGCG, at doses similar in ATE (5–12 µM, was inefficient, suggesting a plausible synergy of several water-soluble tea compounds to explain the ATE beneficial effects.

  18. Structure–Activity Relationship of Oligomeric Flavan-3-ols: Importance of the Upper-Unit B-ring Hydroxyl Groups in the Dimeric Structure for Strong Activities

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    Yoshitomo Hamada

    2015-10-01

    Full Text Available Proanthocyanidins, which are composed of oligomeric flavan-3-ol units, are contained in various foodstuffs (e.g., fruits, vegetables, and drinks and are strongly biologically active compounds. We investigated which element of the proanthocyanidin structure is primarily responsible for this functionality. In this study, we elucidate the importance of the upper-unit of 4–8 condensed dimeric flavan-3-ols for antimicrobial activity against Saccharomyces cerevisiae (S. cerevisiae and cervical epithelioid carcinoma cell line HeLa S3 proliferation inhibitory activity. To clarify the important constituent unit of proanthocyanidin, we synthesized four dimeric compounds, (−-epigallocatechin-[4,8]-(+-catechin, (−-epigallocatechin-[4,8]-(−-epigallocatechin, (−-epigallocatechin-[4,8]-(−-epigallocatechin-3-O-gallate, and (+-catechin-[4,8]-(−-epigallocatechin and performed structure–activity relationship (SAR studies. In addition to antimicrobial activity against S. cerevisiae and proliferation inhibitory activity on HeLa S3 cells, the correlation of 2,2-diphenyl-l-picrylhydrazyl radical scavenging activity with the number of phenolic hydroxyl groups was low. On the basis of the results of our SAR studies, we concluded that B-ring hydroxyl groups of the upper-unit of the dimer are crucially important for strong and effective activity.

  19. Green Tea as an Agricultural Based Health Promoting Food: The Past Five to Ten Years

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    Qin-Yin Shi

    2012-12-01

    Full Text Available The consumption of tea originated in ancient China over 4000 years ago and is currently the second most popular beverage in the world after water. Tea is an aromatic beverage prepared by pouring hot water over cured leaves of the Camellia sinensis plant. The link between tea intake, most notably green tea, and health has resulted in intense research on the components responsible for preventing the onset of several chronic diseases, including atherosclerosis, cancer, obesity and diabetes. In particular, the high levels of chemically diverse phenols (e.g., phenolic acids, flavonoids present in tea exhibit potent protective properties against many of these diseases. Although health related research on green tea and its predominant phenol (catechins has been on-going for decades, major advances have occurred in the last 5–10 years. Therefore, this review focuses on seminal studies reported primarily within the last five years but not extending past ten years on the link between health and green tea with an emphasis on the catechins.

  20. Analysis of Phenolic Compounds and Antioxidant Abilities of Extracts from Germinating Vitis californica Seeds Submitted to Cold Stress Conditions and Recovery after the Stress

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    Stanisław Weidner

    2014-09-01

    Full Text Available The material for this study consisted of stratified seeds of Vitis californica submitted to germination under optimum conditions (+25 °C or under chill stress (+10 °C, also followed by recovery. It has been determined that the germinating seeds contain considerable amounts of tannins, catechins as well as phenolic acids such as gallic, p-coumaric, caffeic and ferulic acids. Gallic acid appeared in the highest amount in the germinating seeds (from 42.40–204.00 µg/g of fresh weight (FW, followed by caffeic acid (from 6.62–20.13 µg/g FW, p-coumaric acid (from 2.59–5.41 µg/g FW, and ferulic acid (from 0.56–0.92 µg/g FW. The phenolic acids occurred mostly in the ester form. Under chill stress, the germinating seeds were determined to contain an elevated total amount of phenolics, as well as raised levels of condensed tannins, catechins, gallic acid, and gafeic acid. The levels of p-coumoric and ferulic acids were found to have decreased. In extracts isolated from a sample exposed to low temperature, increased antioxidant activity and reduction potential were also demonstrated. Tissue of the germinating seeds which underwent post-stress recovery was found to have less total phenolics.

  1. Major Phenolic Compounds, Antioxidant Capacity and Antidiabetic Potential of Rice Bean (Vigna umbellata L. in China

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    Yang Yao

    2012-02-01

    Full Text Available Interest in edible beans as nutraceuticals is increasing. In the present study, the individual phenolic acids, the total phenolic content (TPC, the total flavonoid content (TFC, and the antioxidant and antidiabetic potential of 13 varieties of rice beans from China were investigated. Eight phenolic compounds (catechin, epicatechin, p-coumaric acid, ferulic acid, vitexin, isovitexin, sinapic acid, quercetin were analyzed on an ultra-performance liquid chromatography (UPLC mass spectrometry (MS system. The rice bean varieties had significant differences in total phenolic compounds (ranging from 123.09 ± 10.35 to 843.75 ± 30.15 μg/g, in TPC (ranging from 3.27 ± 0.04 to 6.43 ± 0.25 mg gallic acid equivalents (GAE/g, in TFC (ranging from 55.95 ± 11.16 to 320.39 ± 31.77 mg catechin (CE/g, in antioxidant activity (ranging from 39.87 ± 1.37 to 46.40 ± 2.18 μM·TE/g, in α-glucosidase inhibition activity (ranging from 44.32 ± 2.12 to 68.71 ± 2.19 and in advanced glycation end products formation inhibition activity (ranging from 34.11 ± 0.59 to 75.75 ± 0.33. This study is the first report on phytochemistry and biological activities in rice beans.

  2. Characterization and Antioxidant Properties of the Condensed Tannins from Alaska Cedar Inner Bark

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    Martha Rosales-Castro

    2014-05-01

    Full Text Available The structure and antioxidant activity of condensed tannins isolated from Alaska Cedar inner bark have been investigated. Oligomers of flavan-3-ol were purified by column chromatography (Sephadex LH-20 and analyzed by 13CNMR and MALDI-TOF MS spectrometries. Their antioxidant activities were measured using 1,1’-diphenyl-2-picrylhydrazyl (DPPH, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS free radicals scavenging, ferric reducing/antioxidant power (FRAP, and β-carotene-linoleic acid model system (β-CLAMS assays. Results showed that the condensed tannins consents of both homogeneous and heterogeneous oligomers of procyanidins (catechin/epicatechin and prodelphinidins (gallocatechin/ epigallocatechin flavan-3-ol units; and oligomers from trimmers to heptamers with dominant interflavan linkages B-type as it is most common in proanthocyanidins. Condensed tannins showed significant ntioxidant activity as the median inhibition capacity IC 50 is comparable to the catechin control response. Alaska Cedar inner bark oligomers show high antioxidant capacity, evaluated by both methods based on electron transfer mechanisms and hydrogen atom transfer reactions. This bark may be considered as a new source of natural antioxidants for nutraceutical ingredients.

  3. MANAGEMENT OF MALOLACTIC FERMENTATION AND INFLUENCE ON CHEMICAL COMPOSITION OF AGLIANICO RED WINES

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    S. Suriano

    2015-09-01

    Full Text Available A study has been carried out to determine the effects of lactic acid bacteria inoculation time on the fundamental components, procyanidins and biogenic amines content of Aglianico wines produced in Apulia region. Three different malolactic fermentation (MLF techniques were compared: the co-inoculation, the sequential inoculation, and the traditional technique (spontaneous MLF. In the co-inoculation technique there was a delayed start and a late finish of the alcoholic fermentation. The colour intensity of the wine obtained with a spontaneous MLF was higher both at racking and after 12 months. Significant changes in content of flavan-3-ols were found in wines made with different MLF managements. The levels of catechin monomers ((+-catechin, (--epicatechin, (--epicatechin-O-gallate and procyanidin oligomers (B1-B4, and trimer C1 were lower in the co-inoculation wine. In the wine produced with a spontaneous MLF, the content of biogenic amines was significantly higher compared to the other two wines.

  4. Advantages of the Biomimetic Nanostructured Films as an Immobilization Method vs. the Carbon Paste Classical Method

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    Maria Luz Rodríguez-Méndez

    2012-11-01

    Full Text Available Tyrosinase-based biosensors containing a phthalocyanine as electron mediator have been prepared by two different methods. In the first approach, the enzyme and the electron mediator have been immobilized in carbon paste electrodes. In the second method, they have been introduced in an arachidic acid Langmuir-Blodgett nanostructured film that provides a biomimetic environment. The sensing properties of non-nanostructured and nanostructured biosensors towards catechol, catechin and phenol have been analyzed and compared. The enzyme retains the biocatalytic properties in both matrixes. However, the nanostructured biomimetic films show higher values of maximum reaction rates and lowest apparent Michaelis-Menten constants. In both types of sensors, the sensitivity follows the decreasing order catechol > catechin > phenol. The detection limits observed are in the range of 1.8–5.4 μM for Langmuir-Blodgett biosensors and 8.19–8.57 μM for carbon paste biosensors. In summary, it has been demonstrated that the Langmuir-Blodgett films provide a biomimetic environment and nanostructured biosensors show better performances in terms of kinetic, detection limit and stability.

  5. Salix daphnoides: A Screening for Oligomeric and Polymeric Proanthocyanidins

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    Stefan Wiesneth

    2015-07-01

    Full Text Available In the present study, a qualitative analysis of proanthocyanidins (PAs from an aqueous-methanolic extract of Salix daphnoides VILL. bark is described. Procyanidin B1 (1, B2 (2, B3 (3, B4 (4, C1 (5, epicatechin-(4β→8-epicatechin-(4β→8-catechin (6 and epicatechin-(4β→8-epicatechin-(4β→8-epicatechin-(4β→8-catechin (7 have been isolated by a combination of different chromatographic separations on Sephadex® LH-20-, MCI®-, Diol-and RP-18-phases. Mass spectrometry, 1D- and 2D-NMR, circular dichroism and polarimetry were used for their structure elucidation and verification by comparison with the literature. Additionally, two fractions of very polar flavan-3-ols were compared: “regular” polymeric PAs received at the very end of the Sephadex® LH-20 chromatography showing no mobility on silica TLC and “unusual” PAs with the same RF-value but already eluting together with flavonoids in the Sephadex® LH-20 system. These “unusual” PAs were subsequently enriched by centrifugal partition chromatography (CPC. 13C-NMR, polarimetry, thiolysis, acid hydrolysis and phloroglucinol degradation were used to characterize both fractions. Differences in the composition of different flavan-3-ol units and the middle chain length were observed.

  6. Green tea inhibited the elimination of nephro-cardiovascular toxins and deteriorated the renal function in rats with renal failure.

    Science.gov (United States)

    Peng, Yu-Hsuan; Sweet, Douglas H; Lin, Shiuan-Pey; Yu, Chung-Ping; Lee Chao, Pei-Dawn; Hou, Yu-Chi

    2015-01-01

    Chronic kidney disease (CKD) is a major health problem worldwide. Indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are highly protein-bound nephro-cardiovascular toxins, which are not efficiently removed through hemodialysis. The renal excretions of IS and PCS were mediated by organic anion transporters (OATs) such as OAT1 and OAT3. Green tea (GT) is a popular beverage containing plenty of catechins. Previous pharmacokinetic studies of teas have shown that the major molecules present in the bloodstream are the glucuronides/sulfates of tea catechins, which are putative substrates of OATs. Here we demonstrated that GT ingestion significantly elevated the systemic exposures of endogenous IS and PCS in rats with chronic renal failure (CRF). More importantly, GT also significantly increased the levels of serum creatinine (Cr) and blood urea nitrogen (BUN) in CRF rats. Mechanism studies indicated that the serum metabolites of GT (GTM) inhibited the uptake transporting functions of OAT1 and OAT3. In conclusion, GT inhibited the elimination of nephro-cardiovascular toxins such as IS and PCS, and deteriorated the renal function in CRF rats. PMID:26552961

  7. Total synthesis of proanthocyanidin A1, A2, and their stereoisomers.

    Science.gov (United States)

    Sharma, Pradeep K; Romanczyk, Leo J; Kondaveti, Leelakrishna; Reddy, Bollu; Arumugasamy, Jeeva; Lombardy, Richard; Gou, Yanni; Schroeter, Hagen

    2015-05-15

    The first novel stereoselective synthesis of naturally occurring A1 (1) and A2 proanthocyanidins (2) has been achieved. The key synthetic steps involved (a) the formation of a coupled product (13 or 14) between an open chain C-ring C-4 hydroxyethoxy analogue of either (+)-catechin or (-)-epicatechin with 5,7,3',3'-tetra-O-benzyl-(+)-catechin/-(-)-epicatechin in the presence of bentonite clay K-10, (b) removal of benzyl protecting groups under mild catalytic hydrogenation conditions to form the desired A-type compound in situ as a mixture of diastereomers via ketal/oxonium ion/carbonium ion formation, and (c) separation of the diasteromers via silica gel column chromatography. The structures of A1 and A2 proanthocyanidins were unequivocally established by analytical comparison to the natural products. Following this methodology, an additional six diastereomers of proanthocyanidins A1 and A2 have been synthesized. A plausible mechanism for the formation of the A-type linkage in proanthocyanidins has been proposed. PMID:25927567

  8. Comparison on Phenolic Compounds and Antioxidant Properties of Cabernet Sauvignon and Merlot Wines from Four Wine Grape-Growing Regions in China

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    Bao Jiang

    2012-07-01

    Full Text Available The antioxidant activities in the Cabernet Sauvignon and Merlot wines from four wine grape-growing regions in China were measured by different analytical assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH·, cupric reducing antioxidant capacity (CUPRAC, superoxide radical-scavenging activity (SRSA and the contents of total phenols, total flavonoids, total flavanols and total anthocyanins were determined. The results showed that the contents of phenolic compounds and the levels of antioxidant activity in the wine samples greatly varied with cultivar and environmental factors of vine growth. The contents of phenolic compounds and antioxidant activities in Cabernet Sauvignon and Merlot wines from the Yuquanying region of Ningxia were significantly higher than other three regions, followed by the wines from Shacheng region of Hebei, and these parameters were the lowest in Cabernet Sauvignon and Merlot wines from the Changli regions of Hebei and Xiangning region of Shanxi. Taken together, a close relationship between phenolic subclasses and antioxidant activity was observed for the wine samples. Moreover, there were significant discrepancies in the individual phenolic composition and content of four regional Cabernet Sauvignon and Merlot wines, among which the individual phenolic compounds (catechin, epicatechin, cinnamic acid, quercetin-3-O-glucuronide, quercetin-3-O-glucoside, laricitrin-3-O-glucoside and isorhamnetin-3-O-glucoside revealed a significant correlation (p < 0.05 with the antioxidant capacity in present study, especially for catechin and epicatechin.

  9. Effect of natural compounds on reducing formaldehyde emission from plywood

    Science.gov (United States)

    Uchiyama, Shigehisa; Matsushima, Erica; Kitao, Nahoko; Tokunaga, Hiroshi; Ando, Masanori; Otsubo, Yasufumi

    The effects of natural compounds on reducing formaldehyde emission from plywood were investigated. Urea, catechin and vanillin were examined as the natural formaldehyde reducers. The microemission cell, with an internal volume of 35 ml, the maximum exposed test surface area of 177 cm 2 and an air purge flow rate of 50 ml min -1, was used to measure specific emission rate (SER). In the case of no reducer treatment, formaldehyde emission from plywood was fast and SERs were 4.4 mg m -2 h -1 at 30 °C and 15 mg m -2 h -1 at 60 °C. When this plywood was treated with the natural compounds, the SERs of formaldehyde were decreased at all temperatures. In the case of urea treatment, the SERs of formaldehyde decreased to 0.30 mg m -2 h -1 at 30 °C and 0.65 mg m -2 h -1 at 60 °C. When the urea treatment was applied to the inside of kitchen cabinet (made from plywood; 270 cm wide, 60 cm deep, 250 cm high), the concentration of formaldehyde was reduced substantially from 1600 to 130 μg m -3. The reducing effect of formaldehyde continued during the observation period (6 months), with a mean concentration of 100 μg m -3. Reducers in the plywood would react with released formaldehyde. Application of natural compounds such as urea, catechin and vanillin could provide a simple and effective approach for suppressing formaldehyde emission from plywood.

  10. Flavonoids, total phenolics and antioxidant capacity: comparison between commercial green tea preparations

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    Débora Harumi Kodama

    2010-12-01

    Full Text Available The potential health benefits attributed to green tea and its catechins such as antioxidant effects, cancer chemoprevention, and weight loss have led to a huge increase of green tea products in the food market. The objectives of this work were to analyze and compare these products in terms of phenolic contents and in vitro antioxidant capacity including tea bags, dehydrated leaves, and ready-to-drink preparations after standardization of the infusion preparation procedure. Total phenolics content in 1 cup of the different teas varied from 90 to 341 mg of catechin equivalents, and the highest and the lowest values were both those of the ready-to-drink products. Infusions prepared from tea bags had contents varying from 96 to 201 mg.200 mL-1, and there were no significant differences among batches. The DPPH radical scavenging and the Oxygen Radical Absorbing Capacities (ORAC varied largely among the different tea preparations, from 23 to 131 mmoles of Trolox Equivalents (TE.200 mL-1 (DPPH, and from 1.2 to 5.1 mmoles of TE.200 mL-1 (ORAC, but again there were no differences among infusions or ready-to-drink commercial preparations. However, the antioxidant capacity of ready-to-drink products was partially due to the presence of other non-phenolic compounds such as ascorbic acid

  11. Molecular evaluation of herbal compounds as potent inhibitors of acetylcholinesterase for the treatment of Alzheimer's disease.

    Science.gov (United States)

    Chen, Yan-Xiu; Li, Guan-Zeng; Zhang, Bin; Xia, Zhang-Yong; Zhang, Mei

    2016-07-01

    Alzheimer's disease (AD) is a progressive disease and the predominant cause of dementia. Common symptoms include short-term memory loss, and confusion with time and place. Individuals with AD depend on their caregivers for assistance, and may pose a burden to them. The acetylcholinesterase (AChE) enzyme is a key target in AD and inhibition of this enzyme may be a promising strategy in the drug discovery process. In the present study, an inhibitory assay was carried out against AChE using total alkaloidal plants and herbal extracts commonly available in vegetable markets. Subsequently, molecular docking simulation analyses of the bioactive compounds present in the plants were conducted, as well as a protein‑ligand interaction analysis. The stability of the docked protein‑ligand complex was assessed by 20 ns molecular dynamics simulation. The inhibitory assay demonstrated that Uncaria rhynchophylla and Portulaca oleracea were able to inhibit AChE. In addition, molecular docking simulation analyses indicated that catechin present in Uncaria rhynchophylla, and dopamine and norepinephrine present in Portulaca oleracea, had the best docking scores and interaction energy. In conclusion, catechin in Uncaria rhynchophylla, and dopamine and norepinephrine in Portulaca oleracea may be used to treat AD. PMID:27176468

  12. Identification of polyphenolic compounds in the flesh of Argan (Morocco) fruits.

    Science.gov (United States)

    Khallouki, Farid; Haubner, Roswitha; Ricarte, Irvila; Erben, Gerhard; Klika, Karel; Ulrich, Cornelia M; Owen, Robert W

    2015-07-15

    High performance liquid chromatography coupled with negative electrospray ionization (HPLC-ESI) along with fragmentation patterns generated by nano-electrospray ionization (nano-ESI-MS-MS) and NMR techniques were utilized for the identification of phenolic compounds in Argan fruits. A total of 15.4 g/kg was determined represented by catechins (39%), flavonoids (28%), procyanidins (26%), free phenolic acids (6%) and phenolic acid glycosides (1%). Twenty-one phenolic compounds were identified for the first time in Argan fruits namely III. epicatechin-(4β→8)-catechin dimer (procyanidin B1), IV. p-coumaric acid glycoside, VI. epicatechin-(4β→8)-epicatechin dimer (procyanidin B2), VIII. caffeic acid glycoside, XIX. epicatechin-(4β→8)-epicatechin-(4β→8)-epicatechin trimer (procyanidin C1), X. p-hydroxybenzaldehyde XI. ferulic acid glycoside, XII. vanillic acid, XIII. sinapic acid glycoside, XVI. p-coumaric acid, XVII. ferulic acid, XVIII. sinapic acid, XIX. rutin pentoside, XX. quercetin glycopentoside, XXI. 4,4'-dihydroxy-3,3'-imino-di-benzoic acid, XXV. quercetin-3-O-rhamnogalactoside, XXVII. quercetin glycohydroxybenzoate, XXVIII. quercetin glycocaffeate, XXIX. quercetin glycosinapate, XXX. quercetin glycoferulate and XXXI. quercetin glycocoumarate. PMID:25722154

  13. Effects of Flavonoids on Rumen Fermentation Activity, Methane Production, and Microbial Population

    Directory of Open Access Journals (Sweden)

    Ehsan Oskoueian

    2013-01-01

    Full Text Available This research was carried out to evaluate the effects of flavone, myricetin, naringin, catechin, rutin, quercetin, and kaempferol at the concentration of 4.5% of the substrate (dry matter basis on the rumen microbial activity in vitro. Mixture of guinea grass and concentrate (60 : 40 was used as the substrate. The results showed that all the flavonoids except naringin and quercetin significantly ( decreased the dry matter degradability. The gas production significantly ( decreased by flavone, myricetin, and kaempferol, whereas naringin, rutin, and quercetin significantly ( increased the gas production. The flavonoids suppressed methane production significantly (. The total VFA concentration significantly ( decreased in the presence of flavone, myricetin, and kaempferol. All flavonoids except naringin and quercetin significantly ( reduced the carboxymethyl cellulase, filter paperase, xylanase, and β-glucosidase activities, purine content, and the efficiency of microbial protein synthesis. Flavone, myricetin, catechin, rutin, and kaempferol significantly ( reduced the population of rumen microbes. Total populations of protozoa and methanogens were significantly ( suppressed by naringin and quercetin. The results of this research demonstrated that naringin and quercetin at the concentration of 4.5% of the substrate (dry matter basis were potential metabolites to suppress methane production without any negative effects on rumen microbial fermentation.

  14. Stripping voltammetry of flavonoids

    International Nuclear Information System (INIS)

    The electrochemical behavior of the flavonoids hesperidin, quercetin, naringin, rutin, catechin, epicatechin and caffeic acid at the mercury electrode (HMDE, DME) and at a glassy carbon electrode has been studied by differential pulse polarography. Determination of flavonoids can be achieved either by direct reduction of the carbonyl group in the gamma-pyron ring, indirectly by cathodic stripping voltammetry via the formation of different flavonoid-mercury complexes at the mercury electrode surface and by adsorptive stripping voltammetry via the direct oxidation of aromatic o-dihydroxy groups. The advantage of stripping voltammetry is higher sensitivity and due to the possibility of higher sample dilution less influence of matrix effects. The application by cathodic stripping voltammetry to the determination of hesperidin in orange juice, hesperidin and rutin in helopyrin(R) tablets, a phytopharmaceutical preparation, naringin in grapefruit juice is demonstrated. Also the application by adsorptive stripping voltammetry at a glassy carbon electrode to the determination of quercetin in blood and sinupret, a phytopharmaceutical preparation and catechin in beer is demonstrated. Both methods are suitable for the determination of low flavonoid concentrations down to the ppb concentration range. (author)

  15. Two New Monoterpene Glycosides from Qing Shan Lu Shui Tea with Inhibitory Effects on Leukocyte-Type 12-Lipoxygenase Activity

    Directory of Open Access Journals (Sweden)

    Ding Zhi Fang

    2013-04-01

    Full Text Available We evaluated the inhibitory effect of 12 Chinese teas on leukocyte-type 12-lipoxygenase (LOX activity. Tea catechins such as epigallocatechin gallate have been known to exhibit leukocyte-type 12-LOX inhibition. Qing Shan Lu Shui, which contains lower catechin levels than the other tested teas, suppressed leukocyte-type 12-LOX activity. To characterize the bioactive components of Qing Shan Lu Shui, leukocyte-type 12-LOX inhibitory activity–guided fractionation of the aqueous ethanol extract of the tea was performed, resulting in the isolation of two new monoterpene glycosides: liguroside A (1 and B (2. The structures of compounds 1 and 2 were characterized as (2E,5E-7-hydroperoxy-3,7-dimethyl-2,5-octadienyl-O-(α-L-rhamnopyranosyl-(1″→3′-(4′″-O-trans-p-coumaroyl-β-D-glucopyranoside and (2E,5E-7-hydroperoxy-3,7-dimethyl-2,5-octa-dienyl- O-(α-L-rhamnopyranosyl-(1″→3′-(4′″-O-cis-p-coumaroyl-β-D-glucopyranoside, respectively, based on spectral and chemical evidence. Ligurosides A (1 and B (2 showed inhibitory effects on leukocyte-type 12-LOX activity, with IC50 values of 1.7 and 0.7 μM, respectively.

  16. Green tea polyphenol epigallocatechin gallate activates TRPA1 in an intestinal enteroendocrine cell line, STC-1.

    Science.gov (United States)

    Kurogi, Mako; Miyashita, Megumi; Emoto, Yuri; Kubo, Yoshihiro; Saitoh, Osamu

    2012-02-01

    A characteristic astringent taste is elicited by polyphenols. Among the polyphenols, catechins and their polymers are the most abundant polyphenols in wine and tea. A typical green tea polyphenol is epigallocatechin gallate (EGCG). Currently, the mechanism underlying the sensation of astringent taste is not well understood. We observed by calcium imaging that the mouse intestinal endocrine cell line STC-1 responds to the astringent compound, EGCG. Among major catechins of green tea, EGCG was most effective at eliciting a response in this cell line. This cellular response was not observed in HEK293T or 3T3 cells. Further analyses demonstrated that the 67-kDa laminin receptor, a known EGCG receptor, is not directly involved. The Ca(2+) response to EGCG in STC-1 cells was decreased by inhibitors of the transient receptor potential A1 (TRPA1) channel. HEK293T cells transfected with the mouse TRPA1 (mTRPA1) cDNA showed a Ca(2+) response upon application of EGCG, and their response properties were similar to those observed in STC-1 cells. These results indicate that an astringent compound, EGCG, activates the mTRPA1 in intestinal STC-1 cells. TRPA1 might play an important role in the astringency taste on the tongue. PMID:21890837

  17. The biochemistry and technology of tea manufacture.

    Science.gov (United States)

    Bokuchava, M A; Skobeleva, N I

    1980-01-01

    This review surveys tea-production technology, chemistry of raw and manufactured tea as well as tea tasting appraisal and chemical analysis of manufactured tea. The paper describes the healthful properties of tea, gives general information on the tea plant and manufactured tea, and presents classification of teas as related to the processing of black green, yellow, and red tea, green pressed tea as well as instant tea and tea dyes. The paper discusses the chemical composition of raw and manufactured tea as well as approaches to the evaluation of tea quality--tea tasting appraisal and chemical analysis. The paper is supplied with the conclusions and references. The section on the healthful properties of tea discusses various aspects of catechin effects--vitamin P, antimicrobial, antioxidative and radioprotective effects. Also described are favorable effects of tea alkaloids--caffeine, theobromine, theophylline that dilatate cerebral vessels and alleviate headaches. The section on the production of different teas (black, green, yellow, red, instant teas, and tea dyes) considers technological methods and biochemical bases of various types of tea manufacture. The role of tea leaf enzymes in the oxidative processes determining the tea quality is discussed in detail. This section also describes the contribution of thermochemical processes into the formation of tea flavor. The compounds dictating tea taste and aroma are discussed, particularly tannins and catechins, volatile oils, nitrogen compounds, and some other substances. PMID:6996921

  18. The Effects of Bud Load and Applied Water Amounts on the Biochemical Composition of the ‘Narince’ Grape Variety (Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Serpil GOK TANGOLAR

    2015-12-01

    Full Text Available This study evaluated the effects of various bud load and water amounts (WA on the berry composition of the ‘Narince’ white wine grape variety. Two water amounts (WA-I and WA-II administered during growth stages or a non-irrigated (rain-fed control treatment were paired with two different bud loads (K (normal and 2K (two-fold buds to assess their effects on sugar, organic acid and  phenolic compound contents, as well as antioxidant capacity of the berries for a white wine grape variety ‘Narince’. Despite a slight decrease observed only in sugars in the second year, increases in all phenolic compounds examined (especially in catechin and epicatechin were detected in the WA-I application. The total phenolic compound values obtained for 2K in the same application was also high. The antioxidant capacity values were not significantly affected by the irrigation or bud load applications. Therefore, a 2K bud load with WA-I treatments in which 50% and 75% of the cumulative evaporation from the Class A pan during berry set to veraison and veraison to ripening, respectively, are recommended for irrigation in high plateau viticulture. By maintaining or increasing the fruit composition of ‘Narince’ grapes, these treatments can optimize grape yield and the earnings of growers. In all applications, glucose (among the sugars, tartaric acid (among the organic acids, and catechin and epicatechin (among the phenolic compounds were higher than their counterparts.

  19. Interaction of Catechu Dye with DNA: Spectroscopic and In Silico Approach.

    Science.gov (United States)

    Hemachandran, Hridya; Anantharaman, Amrita; Priya, Rajendra Rao; Doss, George Priya; Siva, Ramamoorthy

    2016-04-01

    Catechin, a yellow colored molecule obtained from the wood of Acacia catechu was analyzed for its interaction with synthetic DNA duplexes using spectroscopic analysis. UV-Visible spectroscopic analysis revealed the non-intercalative binding mode. Fourier Transform Infrared spectroscopy (FTIR) analysis expose chemical shift indicated by various vibrational stretches and an increase in the intensity of base stacking was observed by Circular Dichroism (CD), respectively. This inference was further confirmed through nuclear staining technique and also in electrophoretic technique; the dye quenches the fluorescent intensity of ethidium bromide. The result of fluorescence spectroscopy was in concordance with the electrophoretic technique. In addition, the spectroscopic results were in accordance with the molecular docking studies of specific catechin compound from the catechu dye with CT-DNA. This kind of site specificity is a gain in the medicinal field as the drug can be DNA targeted for cancer therapeutics. The present work reveals that catechu dye has a noteworthy application in the field of medical bioscience. PMID:26913965

  20. Development of a Recombinant Escherichia coli Strain for Overproduction of the Plant Pigment Anthocyanin.

    Science.gov (United States)

    Lim, Chin Giaw; Wong, Lynn; Bhan, Namita; Dvora, Hila; Xu, Peng; Venkiteswaran, Sankaranarayanan; Koffas, Mattheos A G

    2015-09-01

    Anthocyanins are water-soluble colored pigments found in terrestrial plants and are responsible for the red, blue, and purple coloration of many flowers and fruits. In addition to the plethora of health benefits associated with anthocyanins (cardioprotective, anti-inflammatory, antioxidant, and antiaging properties), these compounds have attracted widespread attention due to their promising potential as natural food colorants. Previously, we reported the biotransformation of anthocyanin, specifically cyanidin 3-O-glucoside (C3G), from the substrate (+)-catechin in Escherichia coli. In the present work, we set out to systematically improve C3G titers by enhancing substrate and precursor availability, balancing gene expression level, and optimizing cultivation and induction parameters. We first identified E. coli transporter proteins that are responsible for the uptake of catechin and secretion of C3G. We then improved the expression of the heterologous pathway enzymes anthocyanidin synthase (ANS) and 3-O-glycosyltransferase (3GT) using a bicistronic expression cassette. Next, we augmented the intracellular availability of the critical precursor UDP-glucose, which has been known as the rate-limiting precursor to produce glucoside compounds. Further optimization of culture and induction conditions led to a final titer of 350 mg/liter of C3G. We also developed a convenient colorimetric assay for easy screening of C3G overproducers. The work reported here constitutes a promising foundation to develop a cost-effective process for large-scale production of plant-derived anthocyanin from recombinant microorganisms. PMID:26150456

  1. Changes in the composition of raw tea leaves from the Korean Yabukida plant during high-temperature processing to pan-fried Kamairi-cha green tea.

    Science.gov (United States)

    Friedman, Mendel; Levin, Carol E; Choi, Suk-Hyun; Lee, Seung-Un; Kozukue, Nobuyuki

    2009-06-01

    To develop a better understanding of compositional changes occurring during the production of commercial teas, we determined by high-performance liquid chromatography (HPLC) changes in ingredient levels during each of several manufacturing steps used to produce Kamairi-cha, a premium green tea. Kamairi-cha uses pan-frying instead of the usual blanching technique to inactivate the enzymes responsible for producing traditional black tea. The resulting tea lacks the characteristic bitterness of green tea, producing a green tea that is described as sweet tasting. The processing steps used to produce this pan-fried tea were as follows: 1st roasting, 1st rolling, 2nd roasting, 2nd rolling, 1st firing, and 2nd firing. The results show that during production at temperatures up to 300 degrees C, raw leaves lost (in percent) 97.3 water, 94 two chlorophylls, 14.3 seven catechins, and 2.75 caffeine. A separate analysis showed that the final product contained 21.67 mg/g dry wt of the biologically active amino acid theanine. The results of this 1st report on changes in individual catechins and other tea ingredients in tea leaves during pan-frying make it possible to select production conditions that maximize levels of beneficial tea ingredients. The possible significance of the results for the human diet is discussed. PMID:19646035

  2. Anticarcinogenic effects of the ethanolic extract of Salix aegyptiaca in colon cancer cells: involvement of Akt/PKB and MAPK pathways.

    Science.gov (United States)

    Enayat, Shabnam; Ceyhan, Müşerref Şeyma; Başaran, Arif Ahmet; Gürsel, Mayda; Banerjee, Sreeparna

    2013-01-01

    The bark from Salix species of plants has been traditionally consumed for its antiinflammatory properties. Because inflammation frequently accompanies the progress of colorectal cancer (CRC), we have evaluated the anticancer properties of the ethanolic extract from the bark (EEB) of S. aegyptiaca, a Salix species endogenous to the Middle East, using HCT-116 and HT29 CRC cell lines. Fresh bark from S. aegyptiaca was extracted with ethanol, fractionated by solvent-solvent partitioning and the fractions were analyzed by tandem mass spectrometry. Catechin, catechol, and salicin were the most abundant constituents of the extract. Interestingly, EEB showed the highest anticancer effect in the colon cancer cells followed by its fractions in ethyl acetate and water, with catechin, catechol, and salicin showing the least efficacy. EEB could strongly reduce the proliferation of the cancer cells, but not of CCD-18Co, normal colon fibroblast cell line. Accompanying this was cell cycle arrest at G1/S independent of DNA damage in the cancer cells, induction of apoptosis through a p53 dependent pathway and an inhibition of PI3K/Akt and MAP Kinase pathways at levels comparable to known commercial inhibitors. We propose that the combination of the polyphenols and flavonoids in EEB contributes toward its potent anticarcinogenic effects. [Supplementary materials are available for this article. Go to the publisher's online edition of Nutrition and Cancer for the following free supplemental resource(s): Supplementary Figure 1 and Supplementary Figure 2.]. PMID:24168160

  3. Discrimination of the production season of Chinese green tea by chemical analysis in combination with supervised pattern recognition.

    Science.gov (United States)

    Xu, Wenping; Song, Qiushuang; Li, Daxiang; Wan, Xiaochun

    2012-07-18

    High-performance liquid chromatography (HPLC) has been used to quantify levels of free amino acids, catechins, and caffeine in Chinese green tea. Levels of free amino acids and catechins in green tea leaves show obvious variation from spring to summer, which is useful information to identify the production season of commercial green tea. Supervised pattern recognition methods such as the K-nearest neighbor (KNN) method and Bayesian discriminant method (a type of linear discriminant analysis (LDA)) were used to discriminate between the production seasons of Chinese green tea. The optimal accuracy of the KNN method was ≤97.61 and ≤94.80% as validated by resubstitution and cross-validation tests, respectively, and that of LDA was ≤95.22 and ≤93.54%, respectively. Compared with LDA, the KNN method did not require a Gaussian distribution and was more accurate than LDA. The KNN method in combination with chemical analysis is recommended for discrimination of the production seasons of Chinese green tea. PMID:22720840

  4. Influence of amphiphilic structures on the stability of polyphenols with different hydrophobicity

    Institute of Scientific and Technical Information of China (English)

    Bergensthl; BJRN

    2007-01-01

    Autooxidation of five polyphenols representing range of different hydrophobicities(catechin gallate (CG),(-)catechin((-)C),epicatechin(EC),epigallocatechin gallate(EGCG)and epigallocatechin(EGC)) in three different aqueous solutions:molecular solution,micellar solution(Tween-20)and liposomal dispersion(soybean lecithin)was monitored by HPLC.The rate of oxidation of the five polyphenols was higher at pH 4.5 than at pH 3.5.Compared with the control,addition of Tween-20(micellar structure)and lecithin(liposomal structure)significantly decreased the degradation of polyphenols.In the presence of lecithin the autooxidation of all the five polyphenols was slower than in the presence of Tween-20. The effective protection of the colloidal structures was compared with the hydrophobicity of the poly- phenols estimated from the partitioning between octanol and water.The protection from oxidation in the presence of the colloidal structures(micellar or liposomal)increased with increasing partitioning of a polyphenol towards the hydrophobic environment.The protecting effect of the colloidal structures was more effective at pH 4.5 than at pH 3.5.

  5. Antioxidant and antiproliferative activities of Desmodium triflorum (L.) DC.

    Science.gov (United States)

    Lai, Shang-Chih; Ho, Yu-Ling; Huang, Shun-Chieh; Huang, Tai-Hung; Lai, Zhen-Rung; Wu, Chi-Rei; Lian, Kuo-Yuan; Chang, Yuan-Shiun

    2010-01-01

    This study evaluated the antioxidant and antiproliferative activities of the crude extract and fractions of Desmodium triflorum (L.) DC. The total phenolic content, 1,1-diphenyl-2- picrylhydrazyl hydrate (DPPH) free radical scavenging activity, trolox equivalent antioxidant capacity (TEAC), reducing power, total flavonoid content of D. triflorum were evaluated for the exploration of its antioxidant activities. Furthermore, its antiproliferative activities were investigated through the MTT method. It was compared with the antioxidant capacities of known antioxidants, including catechin, alpha-tocopherol, trolox and ascorbic acid. Among all fractions, ethyl acetate fraction was the most active in scavenging DPPH and TEAC radicals, of which 0.4 mg was equivalent to 186.6 +/- 2.5 microg and 82.5 +/- 2.1 microg of alpha-tocopherol and trolox respectively. The total phenolic and flavonoid contents of the crude extract were equivalent to 36.60 +/- 0.1 mg catechin and 45.6 +/- 0.6 mg rutin per gram respectively. In the reducing power assay, 1.25 mg of crude extract was similar to 61.2 +/- 0.3 microg of ascorbic acid. For the assessment of the safety and toxicity of D. triflorum, LD(50) of the crude extract was greater than 10 g/kg when administered to mice through gastric intubation. The above experimental data indicated that D. triflorum was a potent antioxidant medicinal plant, and such efficacy may be mainly attributed to its polyphenolic compounds. PMID:20387229

  6. Phytochemical constituents of Mongolian traditional medicinal plants, Chamaerhodos erecta and C. altaica, and its constituents prevents the extracellular matrix degradation factors.

    Science.gov (United States)

    Selenge, Erdenechimeg; Odontuya, Gendaram; Murata, Toshihiro; Sasaki, Kenroh; Kobayashi, Kyoko; Batkhuu, Javzan; Yoshizaki, Fumihiko

    2013-10-01

    Activity-guided isolation of the n-butanol fraction of Chamaerhodos erecta and water soluble fraction of C. altaica resulted in the isolation of 39 compounds, including new compounds identified as 4,5-dihydroxybenzaldehyde-3-O-β-D-glucopyranoside (1) from C. erecta and quercetin-3-O-β-D-glucuronopyranosyl-4'-O-β-D-glucopyranoside (2) from C. altaica. A total of 37 other compounds were identified based on physico-chemical properties and spectroscopic data. Antioxidative activity was evaluated using a DPPH radical-scavenging method, hyaluronidase inhibitory activity, and advanced glycation end products production inhibitory activity of isolated compounds. Some flavonols (4, 6, 9-11, 14, 15), catechins (18, 19), an amino acid (20), a lignan glucoside (23), and tannins (29-39) exhibited potential a free radical scavenging activity while the new compound (1) showed weak activity. A catechin (18) and some of the tannins (32, 33, 35, 36, 38) had moderate hyaluronidase inhibitory activity. Some of flavonoids and tannins prevented advanced glycation end products production, and the IC₅₀ of compounds 3, 9, 14-16, 33, 34, 36, 38, and 39 were determined. PMID:23397240

  7. Transepithelial permeability studies of flavan-3-ol-C-glucosides and procyanidin dimers and trimers across the Caco-2 cell monolayer.

    Science.gov (United States)

    Hemmersbach, Sarah; Brauer, Susanne S; Hüwel, Sabine; Galla, Hans-Joachim; Humpf, Hans-Ulrich

    2013-08-21

    In this study the permeability of two flavanol-C-glucosides (FCglcs) and five dimeric and trimeric flavan-3-ols, namely, procyanidins (PCs), was investigated with the human colon carcinoma cell line (Caco-2) model. These compounds can be found especially in cocoa, and they are of great interest due to their assumed beneficial health effects. Transepithelial electrical resistance (TEER) and capacitance were measured online with a CellZscope device prior to and during the whole experiment to guarantee the maintenance of the barrier properties. The transport experiments with pure, single compounds (50-300 μM) from apical to basolateral side showed slight permeation of PCs A2, B2, and B5 and cinnamtannin B1 (CB1) as well as (-)-catechin-6-C-glucoside (C6Cglc) and (-)-catechin-8-C-glucoside (C8Cglc) of about 0.02-0.2% after 24 h. Transport of PC C1 could not be detected. Inhibition of P-glycoprotein (Pgp) increased the permeation of PC B2 and CB1 to the basolateral side, which indicates that Pgp counteracts the transport of these compounds. Metabolites (epicatechin, 3'- and 4'-O-epicatechin) in very small amounts were detectable only for PC B2. These are the first data concerning the permeability of flavan-3-ol-C-glucosides across the Caco-2 cell monolayer. PMID:23885956

  8. Effects of γ-radiation on microbial load and antioxidant proprieties in green tea irradiated with different water activities

    International Nuclear Information System (INIS)

    The aim of this paper is to study the effect of gamma radiation on green tea irradiated with different water activities. The green tea samples had their Aw adjusted to three values (0.93, 0.65, and 0.17) and were irradiated in 60Co source at doses of 0, 1.0, 1.5, 2.0, 2.5, 5.0, 7.5, and 10.0 kGy. The methods used were: microbiology, total phenolic compounds quantification, antioxidant activity by ORAC, and quantification of the main antioxidants. It was observed that the greater the amount of free water present in the samples, lower was the dose to achieve microbiological control. Despite the irradiation with 5.0 kGy with high water activity has a small decrease in phenolic compounds and in some catechins content, this condition is recommended once was the dose to ensure microbiological safety without interfering in the main catechins and the antioxidant activity. - Highlights: • Higher the Aw, lower is the radiation dose to archive microbiology safety. • The doses up to 10.0 kGy had no effect on antioxidant capacity in all Aw used. • The recommended dose to irradiated green tea is 5.0 kGy

  9. Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

    Science.gov (United States)

    He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun

    2014-06-01

    Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

  10. Anti-Cancer Effects of Green Tea by Either Anti- or Pro- Oxidative Mechanisms.

    Science.gov (United States)

    Hayakawa, Sumio; Saito, Kieko; Miyoshi, Noriyuki; Ohishi, Tomokazu; Oishi, Yumiko; Miyoshi, Mamoru; Nakamura, Yoriyuki

    2016-01-01

    Tea derived from the leaves and buds of Camellia sinensis (Theaceae) is consumed worldwide. Green tea contains various components with specific health-promoting effects, and is believed to exert protective effects against diseases including cancer, diabetes and hepatitis, as well as obesity. Of the various tea components, the polyphenol catechins have been the subject of extensive investigation and among the catechins, (-)-epigallocatechin gallate has the strongest bioactivity in most cases. Our research group has postulated that hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α are targets of green tea constituents including (-)-epigallocatechin gallate for their anti-diabetes, anti-obesity, and anti-hepatitis effects, respectively. Published papers were reviewed to determine whether the observed changes in these factors can be correlated with anti-cancer effects of green tea. Two major action mechanisms of (-)-epigallocatechin gallate have been proposed; one associated with its anti-oxidative properties and the other with its pro-oxidative activity. When reactive oxygen species are assumed to be involved, our findings that (-)-epigallocatechin gallate down- regulated hepatocyte nuclear factor-4α, sterol regulatory element-binding proteins, and tumor necrosis factor-α may explain the anti-cancer effect of green tea as well. However, further studies are required to elucidate which determinant directs (-)-epigallocatechin gallate action as an anti-oxidant or a pro-oxidant for favorable activity. PMID:27221834

  11. Peroxidase as the Major Protein Constituent in Areca Nut and Identification of Its Natural Substrates

    Directory of Open Access Journals (Sweden)

    Yu-Ching Liu

    2013-01-01

    Full Text Available Numerous reports illustrate the diverse effects of chewing the areca nut, most of which are harmful and have been shown to be associated with oral cancer. Nearly all of the studies are focused on the extract and/or low molecular weight ingredients in the areca nut. The purpose of this report is to identify the major protein component in the areca nut. After ammonium sulfate fractionation, the concentrated areca nut extract is subjected to DEAE-cellulose chromatography. A colored protein is eluted at low NaCl concentration and the apparently homogeneous eluent represents the major protein component compared to the areca nut extract. The colored protein shares partial sequence identity with the royal palm tree peroxidase and its peroxidase activity is confirmed using an established assay. In the study, the natural substrates of areca nut peroxidase are identified as catechin, epicatechin, and procyanidin B1. The two former substrates are similarly oxidized to form a 576 Da product with concomitant removal of four hydrogen atoms. Interestingly, oxidation of procyanidin B1 occurs only in the presence of catechin or epicatechin and an additional product with an 864 Da molecular mass. In addition, procyanidin B1 is identified as a peroxidase substrate for the first time.

  12. Effect of pyrogallol on the physiology and biochemistry of litchi fruit during storage

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    Jing Guoxing

    2013-01-01

    Full Text Available Abstract Background Litchi (Litchi chinensis Sonn. fruit are highly perishable and have a very short shelf life, easily turning brown and decaying. This study investigated the efficiency of pyrogallol, a catechin on the physiology and biochemistry in relation to storage life of litchi fruit. Results Fruit were treated with pyrogallol at 1 mM and then stored at ambient temperature (25°C or low temperature (4°C. Compared with control, pyrogallol significantly reduced pericarp browning and delayed the rotting of fruit day 4 at 25°C, and on day 30 at 4°C. The chemical treatment reduced respiration rate and the activities of peroxidase (POD and polyphenol oxidase (PPO, and delayed the loss of membrane permeability. Pyrogallol increased the activity of phenylalanine ammonia-lyase (PAL, delayed the loss of anthocyanin and phenolics, and maintained high 2,2-diphenyl-1-picrlhydrazyl (DPPH radical scavenging activity and reducing power. High performance liquid chromatograph (HPLC analysis clearly indicated that treated fruit contained higher concentration of the four phenolic compounds procyanidin B1, (+-catechin, (−-epicatechin and (−-epicatechin-3-gallate. Conclusions The application of pyrogallol partially reducing pericarp browning and changed quality-related physiological activities and, thus, pyrogallol could have beneficial effects on pericarp browning and fruit decay control, and could be helpful for litchi fruit postharvest storage.

  13. Anti-inflammatory Activity of the Invasive Neophyte Polygonum Cuspidatum Sieb. and Zucc. (Polygonaceae) and the Chemical Comparison of the Invasive and Native Varieties with regard to Resveratrol

    Science.gov (United States)

    Fan, Peihong; Zhang, Tao; Hostettmann, Kurt

    2013-01-01

    Polygonum cuspidatum Sieb. and Zucc. has been traditionally used as a member of many anti-inflammatory polyherbal formulations, but is now a widespread invasive neophyte in Europe and America. To discuss if the invasive variety is chemically identical to the native one in traditional medicine, the different constituents of the invasive variety compared to the native variety were isolated and their anti-inflammatory activity was tested. Resveratroloside and catechin-(4α→8)-catechin, the newly found constituents in the invasive variety, have similar nitric oxide (NO) inhibition potency as that of piceid (the major constituent of P. cuspidatum), but the newly found major constituent, i.e., piceatannol glucoside, showed no apparent effect. On the other hand, as a marker, the total content of resveratrol in the methanol root extract after glucosidase hydrolysis was measured and compared between the invasive and native varieties. The total content of resveratrol measured in the root extracts of the Swiss sample was about 2.5 times less than that of the Chinese one. This study brings attention to the point that when the invasive variety of P. cuspidatum is used in traditional medicine, the chemical difference should be kept in mind. PMID:24716176

  14. Eff ects of natural antioxidants on colour stability, lipid oxidation and metmyoglobin reducing activity in raw beef patties

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    Fang Liu

    2015-03-01

    Full Text Available Background. Minced meats undergo oxidative changes and develop rancidity more quickly than intact muscle since grinding exposes more of the muscle surface to air and microbial contamination. Due to concerns about toxicological safety of synthetic antioxidants, recent studies have put more focus on natural antioxidant compounds derived from food components. Material and methods. The effects of four natural antioxidants (vitamin E, carnosine, grape seed extract and tea catechins on oxidative processes and metmyoglobin reducing activity in raw beef patties during refrigerated (4°C storage were investigated and the results were compared with butylated hydroxyanisole treatment patties. The correlation of lipid oxidation, colour and metmyoglobin reducing activity of beef patties were also studied. Results. Samples treated with carnosine had the highest redness values on the eighth day. Tea catechins, vitamin E and grape seed extract showed higher protective effect against lipid oxidation than carnosine. Metmyoglobin reducing activity increased greatly in all samples during the storage. Signifi cant correlation between redness value and lipid oxidation was demonstrated, while a weak correlation between metmyoglobin reducing activity and any other parameters was shown.

  15. Assessment of polyphenolic compounds, in vitro antioxidant and anti-inflammation properties of Securidaca longepedunculata root barks.

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    Muanda, François Nsemi; Dicko, Amadou; Soulimani, Rachid

    2010-09-01

    The present study was carried out to evaluate the antioxidant activities of the root bark extract of Securidaca longepedunculata. This plant material is commonly used in folk medicine in several parts in the world. The bark extracts of S. longepedunculata were evaluated for their total phenols, flavonoids, anthocyanins, tannins content and total antioxidant capacity. The compounds were identified and quantified both by RP-HPLC and UV spectrophotometer; the antioxidant capacity was assessed by ABTS and DPPH tests and expressed as IC(50). The total phenolic compounds determinate was 9.86mg gallic acid equivalents/g dw, the total flavonoid contents was 5.85mg catechin equivalents/g dw, the total anthocyanin contents was 0.032mg cyanidin-3-glycosyl equivalents/g dw and the condensed tannins content were 1.03mg catechin equivalents/g dw. The major compound identified using RP-HPLC was quercetin (0.98mg/ml). The IC(50) value reached 5.5microg/ml, revealing that the root barks of S. longepedunculata have a very high antioxidant and anti-inflammation properties. PMID:20816646

  16. Pine Bark and Green Tea Concentrated Extracts: Antioxidant Activity and Comprehensive Characterization of Bioactive Compounds by HPLC–ESI-QTOF-MS

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    María de la Luz Cádiz-Gurrea

    2014-11-01

    Full Text Available The consumption of polyphenols has frequently been associated with low incidence of degenerative diseases. Most of these natural antioxidants come from fruits, vegetables, spices, grains and herbs. For this reason, there has been increasing interest in identifying plant extract compounds. Polymeric tannins and monomeric flavonoids, such as catechin and epicatechin, in pine bark and green tea extracts could be responsible for the higher antioxidant activities of these extracts. The aim of the present study was to characterize the phenolic compounds in pine bark and green tea concentrated extracts using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC–ESI-QTOF-MS. A total of 37 and 35 compounds from pine bark and green tea extracts, respectively, were identified as belonging to various structural classes, mainly flavan-3-ol and its derivatives (including procyanidins. The antioxidant capacity of both extracts was evaluated by three complementary antioxidant activity methods: Trolox equivalent antioxidant capacity (TEAC, ferric reducing antioxidant power (FRAP and oxygen radical absorbance capacity (ORAC. Higher antioxidant activity values by each method were obtained. In addition, total polyphenol and flavan-3-ol contents, which were determined by Folin–Ciocalteu and vanillin assays, respectively, exhibited higher amounts of gallic acid and (+-catechin equivalents.

  17. Teores de catequinas e teaflavinas em chás comercializados no Brasil Cathechin and theaflavin levels of teas commercialized in Brazil

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    Simara Matsubara

    2006-06-01

    Full Text Available No presente estudo, foram determinados os teores de catequinas e teaflavinas em três marcas de chá verde e quatro de chá preto comercializadas no Brasil. A metodologia analítica consistiu de extração aquosa bastante simples e cromatografia líquida de alta eficiência. Foi utilizada uma coluna de fase reversa Novapak C18 (3,9 mmx150 mm, 4 µm com um gradiente de água e metanol ambos em ácido fórmico como fase móvel. Em chás verdes, os conteúdos de catequinas (em mg/g de folha seca variaram substancialmente: catequina, 0,8 a 2,8; epigalocatequina, 8 a 44; epigalocatequina galato, 11 a 50; epicatequina, 2,3 a 8,5 e epicatequina galato, 3,1 a 7,3. No caso dos chás pretos, as concentrações (mg/g de folha seca de catequinas estiveram nas faixas de: 10 a 50 de epigalocatequina, 14 a 37 de epigalocatequina galato, 5 a 9 de epicatequina e 10 a 21 de epicatequina galato. As teaflavinas apresentaram variação menor: entre 5 (para teaflavina 3'-galato e 13 mg/g (para teaflavina 3,3'-digalato de folha seca. Amostras de chás muito consumidas no Brasil (erva doce, camomila, erva cidreira, hortelã, boldo, mate, erva mate, maçã e morango também foram investigadas, não sendo encontrada nenhuma catequina ou teaflavina.In the present study, the catechin and theaflavin levels in three brands of green tea and four brands of black tea commercialized in Brazil were determined. The analytical methodology consisted of a very simple aqueous extraction and high performance liquid chromatography. A reverse phase Novapak C18 (3.9 mmx150 mm, 4 µm column was used with a gradient of water and methanol, both in formic acid, as mobile phase. In green tea, the catechin contents (in mg/g of dry leaf varied substantially: catechin, 0.8 to 2.8; epigallocatechin, 8 to 44; epigallocatechin gallate, 11 to 50; epicatechin, 2.3 to 8.5; and epicatechin gallate, 3.1 to 7.3. In the case of black tea, the concentrations (mg/g of dry leaf of catechins were in the ranges

  18. Effect of purified gambir leaves extract to prevent atherosclerosis in rats

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    Nanang Yunarto

    2016-03-01

    , antiaterosklerosis AbstractBackground: Atherosclerosis is a risk factor for coronary heart disease (CHD. Catechin have highantioxidant activity that can prevent atherosclerosis. Gambir (Uncaria gambir, Roxb. leaves extract havehigh catechin content thereby potentially inhibiting atherosclerosis. This research was aimed to examineeffect of purified gambir leaves extract to prevent atherosclerosis in rats.Methods: The experimental laboratory study was conducted in Pharmacy Laboratory and Animal Laboratory,National Institute of Health Research and Development, Ministry of Health, Republic of Indonesia in 2014.Gambir leaves extract were purified to gain optimum catechin. Afterwards, antioxidant activity was testedusing 2.2-diphenyl-1-picrylhydrazyl (DPPH method, with ascorbic acid as positive control. Thirty six whitemale Sprague Dawley rats aged 2.5 months were randomly divided into six groups, i.e. normal control group,negative control group (aquadest, positive control group (atorvastatin 2 mg/200 g bw,extract dose I (20mg/200 g bw, dose II (40 mg/200 g bw and dose III (80 mg/200 g bw. The rats were given high fat diet andtreatment according to their group for 60 days, except for normal control group.Results: Catechin content in the purified gambir leaves extract was 92,69%. From antioxidant activity test, IC50 wasfound to be 11,76 μg/mL. Anti-atherosclerotic activity study shown that compared to negative control, all three dosesof purified gambir leaves extract were able to prevent atherosclerosis through inhibition of aortic wall thickening andfoam cell formation due to high fat diet (p<0.05. Anti-atherosclerotic activity increased with increasing dose.Conclusion: Gambir leaves purified extract had the effect of preventing the thickening of the walls andfoam cell formation rat aorta. (Health Science Journal of Indonesia 2015;6:105-10Keywords: gambir, catechin, antiatherosclerosis

  19. 大黄生、熟饮片质量评价方法研究%Quality Evaluation of Raw Rhubarb and Stewed Rhubarb

    Institute of Scientific and Technical Information of China (English)

    田国芳; 李丽; 张村; 肖永庆; 王云; 黄文倩

    2011-01-01

    目的:探讨建立具有生、熟大黄饮片专属性的质量评价方法.方法:以TLC及HPLC对生、熟大黄饮片进行定性、定量比较分析.结果:石油醚-乙酸乙醋-甲酸(15:5:1)和氯仿-甲醇-甲酸(6:1:0.2)2个展开系统的TLC鉴别和HPLC指纹图谱比较,均可以清晰地反映出2种饮片化学成分组成和含量上的变化.主要化学成分的含量测定显示,除苯丁酮及其苷类成分无明显变化外,其余成分的变化均较显著.结论:可将蒽醌苷及其苷元、二苯乙烯苷及鞣质单体的含量作为大黄生、熟饮片定量分析的指标,其中大黄素-8-O-β-D-葡萄糖苷和儿茶素可作为生大黄饮片的特征指标成分.%Objective: To study the individual quality evaluation standard of raw rhubarb and stewed Rhubarb. Method: Qualitative and quantitative identification of two pieces from rhubarb were performed by using the thin-layer chromatography, HPLC fingerprint chromatogram. Result: The change of quantity and content in pieces could be reflected directly and clearly in HPLC fingerprint chromatogram and the TLC in which two kinds of mobile phase were used. There were notable differences in the content of 5 kinds of free anthraquinone,anthraquinone glycoside, stilbene glycoside, catechin and gallic acid in stewed Rhubarb and raw rhubarb.Conclusion: Suggestion on quality standard of raw rhubarb and stewed Rhubarb should be taken differently by the indicator including the content of free anthraquinone, anthraquinone glycoside, catechin, gallic acid and stilbene glycoside. The emodin-8-O-β-D-glucoside and the catechin are the characteristics index of raw rhubarb.

  20. Gallic acid and gallic acid derivatives: effects on drug metabolizing enzymes.

    Science.gov (United States)

    Ow, Yin-Yin; Stupans, Ieva

    2003-06-01

    Gallic acid and its structurally related compounds are found widely distributed in fruits and plants. Gallic acid, and its catechin derivatives are also present as one of the main phenolic components of both black and green tea. Esters of gallic acid have a diverse range of industrial uses, as antioxidants in food, in cosmetics and in the pharmaceutical industry. In addition, gallic acid is employed as a source material for inks, paints and colour developers. Studies utilising these compounds have found them to possess many potential therapeutic properties including anti-cancer and antimicrobial properties. In this review, studies of the effects of gallic acid, its esters, and gallic acid catechin derivatives on Phase I and Phase II enzymes are examined. Many published reports of the effects of the in vitro effects of gallic acid and its derivatives on drug metabolising enzymes concern effects directly on substrate (generally drug or mutagen) metabolism or indirectly through observed effects in Ames tests. In the case of the Ames test an antimutagenic effect may be observed through inhibition of CYP activation of indirectly acting mutagens and/or by scavenging of metabolically generated mutagenic electrophiles. There has been considerable interest in the in vivo effects of the gallate esters because of their incorporation into foodstuffs as antioxidants and in the catechin gallates with their potential role as chemoprotective agents. Principally an induction of Phase II enzymes has been observed however more recent studies using HepG2 cells and primary cultures of human hepatocytes provide evidence for the overall complexity of actions of individual components versus complex mixtures, such as those in food. Further systematic studies of mechanisms of induction and inhibition of drug metabolising enzymes by this group of compounds are warranted in the light of their distribution and consequent ingestion, current uses and suggested therapeutic potential. However, it