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Sample records for gallic esters displaying

  1. Alkyl esters of gallic acid as anticancer agents: a review.

    PubMed

    Locatelli, Claudriana; Filippin-Monteiro, Fabíola Branco; Creczynski-Pasa, Tânia Beatriz

    2013-02-01

    The current review presents the antitumoral properties of gallic acid and its ester derivatives. Numerous studies have indicated that the alkyl esters are more effective against tumor cell lines than gallic acid, and that this activity is related to their hydrophobic moiety. All related studies have shown that the antitumor activity is interconnected to the induction of apoptosis by different mechanisms and it depends on the cell type. The results presented in this review may help to emphasize that these compounds could be promising as a new alternative for the treatment of cancer, either alone or in combination with other antitumor drugs to potentiate their effects.

  2. Actions of gallic esters on the arachidonic acid metabolism of human polymorphonuclear leukocytes.

    PubMed

    Christow, S; Luther, H; Ludwig, P; Gruner, S; Schewe, T

    1991-04-01

    Gallic esters with a varying chain length of its alcohol moiety produced strong inhibition of the conversion of [1-14C]-arachidonic acid to 5S-hydroxy-6E,8Z,11Z,14Z-eicosatetraenoic acid (5-HETE) by isolated human polymorphonuclear leukocytes. Octyl gallate and decyl gallate were the most powerful inhibitors with a concentration of half-inhibition of about 1 mumol . 1-1. Additionally these compounds caused however at 10 mumol . 1-1 a complete inhibition of the incorporation of arachidonic acid in triacylglycerols and phospholipids which is assumed to be a consequence of the damage to the energy metabolism of the cells. In contrast, the other gallic esters enhance the incorporation of arachidonic acid in the ester lipids in addition to moderate inhibition of the 5-lipoxygenase pathway.

  3. Oxidative dimers produced from protocatechuic and gallic esters in the DPPH radical scavenging reaction.

    PubMed

    Kawabata, Jun; Okamoto, Yasuko; Kodama, Asuka; Makimoto, Terumasa; Kasai, Takanori

    2002-09-11

    DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecules of the intermediate quinone in the reaction with DPPH radical, whereas methyl gallate rapidly gave a symmetrical dimer via a putative quinone precursor. Both dimers are rather unstable and their structures have been deduced by in situ NMR measurements of the reaction mixtures. Gallic acid also gave a corresponding symmetrical dimer in the same reaction as methyl gallate, although protocatechuquinone produced from protocatechuic acid did not yield a Diels-Alder adduct, unlike its methyl ester. Interestingly, these dimer formations were not observed in methanol solution.

  4. Inhibition of rabbit erythroid 15-lipoxygenase and sheep vesicular gland prostaglandin H synthase by gallic esters.

    PubMed

    Luther, H; Jordanov, D; Ludwig, P; Schewe, T

    1991-02-01

    Gallic acid esters possessing a varying chain length of their alcohol moiety were tested for their inhibitory potencies on 15-lipoxygenase from rabbit reticulocytes and prostaglandin H synthase from sheep vesicular glands. Octyl gallate and decyl gallate proved to be the most powerful inhibitors of both enzymes showing concentrations of half-inhibition of about 0.25 mumol/l for the reticulocyte lipoxygenase and of about 25 mumol/l for the prostaglandin H synthase.

  5. Inhibitory effects of gallic acid ester derivatives on Saccharomyces cerevisiae multidrug resistance protein Pdr5p.

    PubMed

    Pereira Rangel, Luciana; Fritzen, Márcio; Yunes, Rosendo Augusto; Leal, Paulo César; Creczynski-Pasa, Tânia Beatriz; Ferreira-Pereira, Antônio

    2010-05-01

    Overexpression of the Saccharomyces cerevisiae ABC transporter Pdr5p confers resistance to a range of structurally unrelated xenobiotics. This property allows Pdr5p to be used as a target for novel multidrug resistance reversal reagents or chemosensitizers. Herein, we report the effects of gallic acid derivatives with substitutions either on the ester moiety or in the benzene ring on the activity of Pdr5p. Compounds with a longer side chain (8-16 carbons) resulted in greater inhibition of Pdr5p ATPase. Derivatives with side chains of 8-12 carbons that retained hydroxyl groups on the benzene ring extensively inhibited Pdr5p ATPase activity. These compounds almost completely inhibited the efflux of the Pdr5p fluorescent substrate Rhodamine 6G and at 25 muM chemosensitized the Pdr5p-overexpressing strain AD124567 to fluconazole (0.4 mg mL(-1)). Gallic acid derivatives may be a new class of Pdr5p inhibitors.

  6. Effect of the esters of gallic acid on model and human blood platelet membranes studied by Fourier transform infrared spectroscopy.

    PubMed

    Qi, S P; Hu, P R

    1993-06-01

    Gallic acid is one of the components of Chinese herbal drug Radix paeoniae used for promoting blood circulation to remove blood stasis. This paper studied the effects of gallic acid and its esters (e.g. ethyl, propyl, isobutyl and butyl gallate) on model and human blood platelet membranes by FTIR which was used for monitoring the physical state of the acyl chain, interfacial and head group region of the membrane lipid bilayer. From the experimental results it can be seen that the gallic acid and its esters have the modifying function on the pure and cholesterol-containing DPPC model membranes, and have the quantity-effective and structural-effective relationships. In addition, it is discovered that these esters have the modifying effect on the structure of human blood platelet membrane and can reverse the effect of ADP. That the effect of the esters of gallic acid counteracts the effect of cholesterol and ADP on human blood platelet perhaps provides a new explanation of the mechanism of Chinese herbal drugs used for promoting blood circulation to remove blood stasis.

  7. Gallic esters of sucrose as efficient radical scavengers in lipid peroxidation.

    PubMed

    Dufour, Claire; Da Silva, Eric; Potier, Pierre; Queneau, Yves; Dangles, Olivier

    2002-06-01

    Three tests of increasing complexity were used to assess the antioxidant activity of five synthetic gallic esters of sucrose bearing 3, 6, 7, or 8 galloyl units. In addition, two of these compounds had 1 or 2 hydrocarbon (C10-C12) acyl chains. Reaction with the DPPH radical led to the evaluation of the number of radicals trapped per galloyl unit n (3-4), as well as the apparent second-order rate constant for H atom donation k (1200-1500/M/s). These results indicated similar contribution and reactivity of all the galloyl units. Inhibition of the AAPH-initiated peroxidation of linoleic acid in a micellar medium confirmed the additive contribution of the galloyl units, whereas the presence of the hydrocarbon acyl chains had no influence. These results suggest an inhibition of initiation at high antioxidant levels and an underlying prooxidant effect of the galloyl radicals at low concentrations. Finally, LDL peroxidation was inhibited in proportion to the number of galloyl units, in agreement with the preceding tests.

  8. Medicinal importance of gallic acid and its ester derivatives: a patent review.

    PubMed

    Choubey, Sneha; Varughese, Lesley Rachel; Kumar, Vinod; Beniwal, Vikas

    2015-01-01

    Gallic acid and its derivatives have a large number of applications in various fields of science. In nature, these compounds are widely distributed in plants and fruits, and thus they are being used as food stuffs, preservatives, etc. directly or indirectly by human community. They have also been implicated as anticarcinogenic, antimicrobial, antimutagenic, antiangiogenic and anti-inflammatory agents besides their use in treating critical diseases like depression, cancer, microbial infections, lipid-related diseases, etc. Herein, an attempt has been made to summarize the important uses of gallic acid derivatives which have extensively been disclosed particularly in various patents. This review would certainly create a great interest of the scientific community toward the developments and uses of gallic acid based compounds in the future.

  9. Medicinal importance of gallic acid and its ester derivatives: a patent review.

    PubMed

    Choubey, Sneha; Varughese, Lesley Rachel; Kumar, Vinod; Beniwal, Vikas

    2015-01-01

    Gallic acid and its derivatives have a large number of applications in various fields of science. In nature, these compounds are widely distributed in plants and fruits, and thus they are being used as food stuffs, preservatives, etc. directly or indirectly by human community. They have also been implicated as anticarcinogenic, antimicrobial, antimutagenic, antiangiogenic and anti-inflammatory agents besides their use in treating critical diseases like depression, cancer, microbial infections, lipid-related diseases, etc. Herein, an attempt has been made to summarize the important uses of gallic acid derivatives which have extensively been disclosed particularly in various patents. This review would certainly create a great interest of the scientific community toward the developments and uses of gallic acid based compounds in the future. PMID:26174568

  10. Inhibitory effect of gallic acid and its esters on 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione in erythrocytes.

    PubMed

    Ximenes, Valdecir F; Lopes, Mariana G; Petrônio, Maicon Segalla; Regasini, Luis Octavio; Silva, Dulce H Siqueira; da Fonseca, Luiz M

    2010-05-12

    The protective effect of gallic acid and its esters, methyl, propyl, and lauryl gallate, against 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione (GSH) in erythrocytes was studied. The inhibition of hemolysis was dose-dependent, and the esters were significantly more effective than gallic acid. Gallic acid and its esters were compared with regard to their reactivity to free radicals, using the DPPH and AAPH/pyranine free-cell assays, and no significant difference was obtained. Gallic acid and its esters not only failed to inhibit the depletion of intracellular GSH in erythrocytes induced by AAPH but exacerbated it. Similarly, the oxidation of GSH by AAPH or horseradish peroxidase/H(2)O(2) in cell-free systems was exacerbated by gallic acid or gallates. This property could be involved in the recent findings on pro-apoptotic and pro-oxidant activities of gallates in tumor cells. We provide evidence that lipophilicity and not only radical scavenger potency is an important factor regarding the efficiency of antihemolytic substances.

  11. Antimicrobial activity of some alkyl esters of gallic acid (3,4,5,-trihydroxybenzoic acid) against Escherichia coli NCTC 5933 with particular reference to n-propyl gallate.

    PubMed

    Boyd, L; Beveridge, E G

    1981-01-01

    The growth inhibitory and bactericidal activities of eight alkyl esters of gallic acid towards Escherichia coli NCTC 5933 have been determined. A previously suggested role for gallic acid and its esters as shikimate antimetabolites could not be substantiated. No induction of gross changes in cell morphology was observed. Bactericidal activity was accompanied only be very slight leakage of general ionic materials from the bacteria. Propyl gallate did not appear to uncouple oxidative phosphorylation from respiration as indicated by its failure to stimulate proton translocation across the cytoplasmic membrane.

  12. Ester derivatives of gallic acid with potential toxicity toward L1210 leukemia cells.

    PubMed

    Locatelli, Claudriana; Rosso, Rober; Santos-Silva, Maria C; de Souza, Camila A; Licínio, Marley A; Leal, Paulo; Bazzo, Maria L; Yunes, Rosendo A; Creczynski-Pasa, Tânia B

    2008-04-01

    Gallic acid and gallates with the same number of hydroxyl groups and varying the length of the side carbon chain, with respective lipophilicity being defined through the ClogP values, were examined for their ability to induce apoptosis (through the DNA ladder fragmentation pattern), mitochondrial and cytoplasmic GSH depletion and NF-kappaB activation in murine lymphoblastic L1210 leukemia cells. A relationship between cytotoxic effect and a limited degree of lipophilicity was observed.

  13. Synthesis of novel polyphenols consisted of ferulic and gallic acids, and their inhibitory effects on phorbol ester-induced Epstein-Barr virus activation and superoxide generation.

    PubMed

    Nomura, Eisaku; Hosoda, Asao; Morishita, Hideko; Murakami, Akira; Koshimizu, Koichi; Ohigashi, Hajime; Taniguchi, Hisaji

    2002-04-01

    We prepared novel polyphenols which were esters composed of two naturally occurring products, ferulic and gallic acids, and investigated their inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Epstein-Barr virus (EBV) activation and superoxide (O2-) generation. Most of these compounds exhibited significant EBV activation suppression at a concentration of 20 microM and in particular, the ester 5f having 2-methyl-1-butyl group showed high activity. The suppressive effects on O2- generation were also observed in most of the esters.

  14. Enzymatic gallic acid esterification.

    PubMed

    Weetal, H H

    1985-02-01

    Gallic acid esters of n-propyl and amyl alcohols have been produced by enzymatic synthesis in organic solvents using immobilized tannase. Studies indicate that maximum esterification of gallic acid occurs with amyl alcohol. The enzyme shows broad alcohol specificity. However, the enzyme exhibits absolute specificity for the acid portion of the ester. Studies were carried out on K(m), V(max), pH, and temperature optima.

  15. Radiation sensitivity and EPR dosimetric potential of gallic acid and its esters

    NASA Astrophysics Data System (ADS)

    Tuner, Hasan; Oktay Bal, M.; Polat, Mustafa

    2015-02-01

    In the preset work the radiation sensitivities of Gallic Acid anhydrous and monohydrate, Octyl, Lauryl, and Ethyl Gallate (GA, GAm, OG, LG, and EG) were investigated in the intermediate (0.5-20 kGy) and low radiation (<10 Gy) dose range using Electron Paramagnetic Resonance (EPR) spectroscopy. While OG, LG, and EG are presented a singlet EPR spectra, their radiation sensitivity found to be very different in the intermediate dose range. At low radiation dose range (<10 Gy) only LG is found to be present a signal that easily distinguished from the noise signals. The intermediate and low dose range radiation sensitivities are compared using well known EPR dosimeter alanine. The radiation yields (G) of the interested material were found to be 1.34×10-2, 1.48×10-2, 4.14×10-2, and 6.03×10-2, 9.44×10-2 for EG, GA, GAm, OG, and LG, respectively at the intermediate dose range. It is found that the simple EPR spectra and the noticeable EPR signal of LG make it a promising dosimetric material to be used below 10 Gy of radiation dose.

  16. Suppression of TNF-α induced NFκB activity by gallic acid and its semi-synthetic esters: possible role in cancer chemoprevention.

    PubMed

    Morais, Mauro C C; Luqman, Suaib; Kondratyuk, Tamara P; Petronio, Maicon S; Regasini, Luis O; Silva, Dulce H S; Bolzani, Vanderlan S; Soares, Christiane P; Pezzuto, John M

    2010-11-01

    Gallic acid (3,4,5-trihydroxybenzoic acid), found in many plants either in free-form or part of tannins, is known to possess anti-microbial, antioxidant and cytotoxic properties. NFκB regulates the expression of several genes involved in carcinogenesis. These include anti-apoptotic, cytokines and cell cycle-regulatory genes. It is well established that the transcriptional factor NFκB is deregulated in many forms of cancer. Thus, agents that can suppress NFκB activation have the potential of suppressing carcinogenesis. In the present investigation, gallic acid was isolated from Alchornea glandulosa (Euphorbiaceae) and eight esters were synthesised. These compounds were evaluated against TNF-α-induced NFκB activation with stably transfected 293/NFκB-Luc human embryonic kidney cells. Gallates with IC(50) values in a range of 10-56 µM mediated inhibitory activity higher than gallic acid (IC(50) 76.0 ± 4.9 µM). In addition to inhibiting NFκB activation, gallic acid mediated a modest cytotoxic effect, and some of the gallates affected cell viability at the tested concentrations. Based on these results, suppression of NFκB activation by gallate esters could play a chemopreventive role in carcinogenesis.

  17. Efficient Diethylzinc/Gallic Acid and Diethylzinc/Gallic Acid Ester Catalytic Systems for the Ring-Opening Polymerization of rac-Lactide.

    PubMed

    Żółtowska, Karolina; Piotrowska, Urszula; Oledzka, Ewa; Sobczak, Marcin

    2015-12-08

    Polylactide (PLA) represents one of the most promising biomedical polymers due to its biodegradability, bioresorbability and good biocompatibility. This work highlights the synthesis and characterization of PLAs using novel diethylzinc/gallic acid (ZnEt₂/GAc) and diethylzinc/propyl gallate (ZnEt₂/PGAc) catalytic systems that are safe for human body. The results of the ring-opening polymerization (ROP) of rac-lactide (rac-LA) in the presence of zinc-based catalytic systems have shown that, depending on the reaction conditions, "predominantly isotactic", disyndiotactic or atactic PLA can be obtained. Therefore, the controlled and stereoselective ROP of rac-LA is discussed in detail in this paper.

  18. Effect of tannic acid on benzo[a]pyrene-DNA adduct formation in mouse epidermis: comparison with synthetic gallic acid esters.

    PubMed

    Baer-Dubowska, W; Gnojkowski, J; Fenrych, W

    1997-01-01

    Tannic acid, a naturally occurring plant phenol, was shown to inhibit the mutagenicity and/or tumorigenicity of several polycyclic aromatic hydrocarbons in mouse skin. In this study the effect of topical application of tannic acid on epidermal aryl hydrocarbon hydroxylase, glutathione S-transferase, and binding of benzo[a]pyrene (B[a]P) to epidermal DNA was compared with the activity of synthetic gallic acid esters. Single topical application of 8 mumol octyl and dodecyl gallate had no effect on the induction of aryl hydrocarbon hydroxylase, whereas propyl gallate and tannic acid increased the enzyme activity by nearly 200%. Application of the phenolics one hour before 0.2 mumol of B[a]P enhanced the enzyme activity, but the observed differences were not significant in comparison with a B[a]P-treated group of mice. Application of dodecyl and octyl gallates to mouse skin resulted in three- and twofold increases, respectively, in the activity of glutathione S-transferase. Combined treatment with dodecyl gallate and B[a]P also resulted in significant enhancement of this enzyme activity. Application of the same dose of tannic acid to mouse skin one hour before the application of 0.2 or 1 mumol of B[a]P afforded 60% inhibition of covalent benzo[a]pyrene-diol-epoxide binding to epidermal DNA. Gallic acid esters with the exception of dodecyl gallate were less effective inhibitors of benzo[a]pyrene-diol-epoxide binding, especially when the higher dose of B[a]P was used. These results indicate that the antitumorigenic activity of tannic acid involves the interaction of the ultimate carcinogen with DNA rather than an altered metabolism. The linkage between gallic acid and glucose in natural plant phenols is also more effective at inhibiting B[a]P binding to epidermal DNA than the linkage with the alkyl group in synthetic gallates.

  19. Relationship between the lipophilicity of gallic acid n-alquil esters' derivatives and both myeloperoxidase activity and HOCl scavenging.

    PubMed

    Rosso, Rober; Vieira, Tiago O; Leal, Paulo C; Nunes, Ricardo J; Yunes, Rosendo A; Creczynski-Pasa, Tânia B

    2006-09-15

    The gallic acid and several n-alkyl gallates, with the same number of hydroxyl substituents, varying only in the side carbonic chain length, with respective lipophilicity defined through the C log P, were studied. It evidenced the structure-activity relationship of the myeloperoxidase activity inhibition and the hypochlorous acid scavenger property, as well as its low toxicity in rat hepatic tissue. The gallates with C log P below 3.0 (compounds 2-7) were more active against the enzyme activity, what means that the addition of 1-6 carbons (C log P between 0.92 and 2.92) at the side chain increased approximately 50% the gallic acid effect. However, a relationship between the HOCl scavenging capability and the lipophilicity was not observed. With these results it is possible to suggest that the gallates protect the HOCl targets through two mechanisms: inhibiting its production by the enzyme and scavenging the reactive specie.

  20. Phenolic acid derivatives with potential anticancer properties--a structure-activity relationship study. Part 1: methyl, propyl and octyl esters of caffeic and gallic acids.

    PubMed

    Fiuza, S M; Gomes, C; Teixeira, L J; Girão da Cruz, M T; Cordeiro, M N D S; Milhazes, N; Borges, F; Marques, M P M

    2004-07-01

    The antiproliferative and cytotoxic properties of polyphenolic acid derivatives, structurally related with the natural models caffeic and gallic acids, have been tested in human cervix adenocarcinoma cells (HeLa). Simultaneous structural information was obtained for these compounds through theoretical ab initio methods. This study was conducted for the following esters: methyl caffeate (MC, 1), propyl caffeate (PC, 2), octyl caffeate (OC, 3), methyl gallate (MG, 4), propyl gallate (PG, 5) and octyl gallate (OG, 6). A significant growth-inhibition effect was assessed for some of these compounds, clearly dependent on their structural characteristics. Marked structure-activity relationships (SARs)--namely the number of hydroxyl ring substituents--were found to rule the biological effect of such systems.

  1. Gallic acid-based alkyl esters synthesis in a water-free system by celite-bound lipase of Bacillus licheniformis SCD11501.

    PubMed

    Sharma, Shivika; Kanwar, Shamsher S; Dogra, Priyanka; Chauhan, Ghanshyam S

    2015-01-01

    Gallic acid (3, 4, 5- trihydroxybenzoic acid) is an important antioxidant, anti-inflammatory, and radical scavenging agent. In the present study, a purified thermo-tolerant extra-cellular lipase of Bacillus licheniformis SCD11501 was successfully immobilized by adsorption on Celite 545 gel matrix followed by treatment with a cross-linking agent, glutaraldehyde. The celite-bound lipase treated with glutaraldehyde showed 94.8% binding/retention of enzyme activity (36 U/g; specific activity 16.8 U/g matrix; relative increase in enzyme activity 64.7%) while untreated matrix resulted in 88.1% binding/retention (28.0 U/g matrix; specific activity 8.5 U/g matrix) of lipase. The celite-bound lipase was successfully used to synthesis methyl gallate (58.2%), ethyl gallate (66.9%), n-propyl gallate (72.1%), and n-butyl gallate (63.8%) at 55(o) C in 10 h under shaking (150 g) in a water-free system by sequentially optimizing various reaction parameters. The low conversion of more polar alcohols such as methanol and ethanol into their respective gallate esters might be due to the ability of these alcohols to severely remove water from the protein hydration shell, leading to enzyme inactivation. Molecular sieves added to the reaction mixture resulted in enhanced yield of the alkyl ester(s). The characterization of synthesised esters was done through fourier transform infrared (FTIR) spectroscopy and (1) H NMR spectrum analysis.

  2. Improved Quantification of Free and Ester-Bound Gallic Acid in Foods and Beverages by UHPLC-MS/MS.

    PubMed

    Newsome, Andrew G; Li, Yongchao; van Breemen, Richard B

    2016-02-17

    Hydrolyzable tannins are measured routinely during the characterization of food and beverage samples. Most methods for the determination of hydrolyzable tannins use hydrolysis or methanolysis to convert complex tannins to small molecules (gallic acid, methyl gallate, and ellagic acid) for quantification by HPLC-UV. Often unrecognized, analytical limitations and variability inherent in these approaches for the measurement of hydrolyzable tannins include the variable mass fraction (0-0.90) that is released as analyte, contributions of sources other than tannins to hydrolyzable gallate (can exceed >10 wt %/wt), the measurement of both free and total analyte, and lack of controls to account for degradation. An accurate, specific, sensitive, and higher-throughput approach for the determination of hydrolyzable gallate based on ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) that overcomes these limitations was developed. PMID:26804199

  3. Improved Quantification of Free and Ester-Bound Gallic Acid in Foods and Beverages by UHPLC-MS/MS.

    PubMed

    Newsome, Andrew G; Li, Yongchao; van Breemen, Richard B

    2016-02-17

    Hydrolyzable tannins are measured routinely during the characterization of food and beverage samples. Most methods for the determination of hydrolyzable tannins use hydrolysis or methanolysis to convert complex tannins to small molecules (gallic acid, methyl gallate, and ellagic acid) for quantification by HPLC-UV. Often unrecognized, analytical limitations and variability inherent in these approaches for the measurement of hydrolyzable tannins include the variable mass fraction (0-0.90) that is released as analyte, contributions of sources other than tannins to hydrolyzable gallate (can exceed >10 wt %/wt), the measurement of both free and total analyte, and lack of controls to account for degradation. An accurate, specific, sensitive, and higher-throughput approach for the determination of hydrolyzable gallate based on ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) that overcomes these limitations was developed.

  4. Gallic acid ester derivatives induce apoptosis and cell adhesion inhibition in melanoma cells: The relationship between free radical generation, glutathione depletion and cell death.

    PubMed

    Locatelli, Claudriana; Leal, Paulo C; Yunes, Rosendo A; Nunes, Ricardo J; Creczynski-Pasa, Tânia B

    2009-10-01

    Malignant melanoma is a lethal disease, and the incidence and mortality associated with it are increasing worldwide. It has a significant tendency to develop both metastasis and resistance to chemotherapy. The tumor cells show abnormal redox regulation, and although the molecular mechanisms involved are not well characterized, they seem to be related to oxidative stress. In a previous study, we showed the antitumoral properties of gallic acid ester derivatives in leukemia cells. Here, we show the effect of octyl, decyl, dodecyl and tetradecyl gallates on B16F10 cells, a melanoma cell line. All compounds induced cytotoxic effects, and the IC(50) values obtained were between 7microM and 17microM after 48h of incubation. Cell death occurred through apoptosis, as demonstrated by the genomic DNA fragmentation pattern. The gallates were able to induce significant production of free radicals, deplete both glutathione and ATP, activate NF-kappaB and promote the inhibition of cell adhesion under the experimental conditions. The glutathione depletion induced by these compounds was related to the inhibition of gamma-glutamylcysteine synthase activity. These results suggest that gallates induce tumoral cell death through apoptosis as a consequence of oxidative stress, though they use different mechanisms to do so. These findings are important since melanoma cells are resistant to death because of their high level of antioxidant defense, adhesion capability and propensity to metastasize.

  5. Evaluation of anti-herpetic and antioxidant activities, and cytotoxic and genotoxic effects of synthetic alkyl-esters of gallic acid.

    PubMed

    Savi, Luciane A; Leal, Paulo C; Vieira, Tiago O; Rosso, Rober; Nunes, Ricardo J; Yunes, Rosendo A; Creczynski-Pasa, Tânia B; Barardi, Célia R M; Simões, Cláudia M O

    2005-01-01

    The n-alkyl esters of gallic acid (CAS 13857-8) have a diverse range of uses as antioxidants in food, cosmetics and pharmaceutical industries. Pharmaceutical studies performed with these compounds have found that they have many therapeutic potentialities including anti-cancer, antiviral and antimicrobial properties. However, more interest has been devoted to their antioxidant activity due to the ability to scavenge and reduce reactive oxygen species (ROS) formation. In this study, gallic acid and 14 different alkyl gallates were tested. The cytotoxicity and anti-herpetic (HSV-1, KOS and 29-R strains) activity were studied by using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) colorimetric assay and the cell viability by using the Trypan blue dye exclusion method. The genotoxicity was studied by the Comet assay and the antioxidant activity by using the DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging and microsomal lipid peroxidation-inhibiting activities. The results showed that all the tested compounds have anti-herpetic activity at non cytotoxic concentrations with selectivity indices (SI = CC50/EC50) varying from 0.89 to 18.34, depending on the used HSV-1 strain. It was observed that all tested alkyl gallates showed some degree of genotoxicity, at the tested concentrations, except cetyl gallate, at 256.60 micromol/L (p <0.05, t-Student test), probably induced by ROS released by infected cells and/or by the alkyl gallates that were not antioxidants, at the tested concentrations, in which they demonstrated anti-herpetic activity. The hydroxyl groups can induce DNA damage due interactions with some metal ions, which are naturally present in the culture medium supplemented with fetal bovine serum, probably explaining the genotoxicity detected. However, the obtained results showed considerable antioxidant activity at smaller concentrations, when compared to quercetin which is considered as a reference drug due to its already described

  6. Maxima in antioxidant distributions and efficiencies with increasing hydrophobicity of gallic acid and its alkyl esters. The pseudophase model interpretation of the "cutoff effect".

    PubMed

    Losada Barreiro, Sonia; Bravo-Díaz, Carlos; Paiva-Martins, Fátima; Romsted, Laurence S

    2013-07-01

    Antioxidant (AO) efficiencies are reported to go through maxima with increasing chain length (hydrophobicity) in emulsions. The so-called "cutoff" after the maxima, indicating a decrease in efficiency, remains unexplained. This paper shows, for gallic acid (GA) and propyl, octyl, and lauryl gallates (PG, OG, and LG, respectively), that at any given volume fraction of emulsifier, the concentrations of antioxidants in the interfacial region of stripped corn oil emulsions and their efficiency order follow PG > GA > OG > LG. These results provide clear evidence that an AO's efficiency correlates with its fraction in the interfacial region. AO distributions were obtained in intact emulsions by using the pseudophase kinetic model to interpret changes in observed rate constants of the AOs with a chemical probe, and their efficiencies were measured by employing the Schaal oven test. The model provides a natural explanation for the maxima with increasing AO hydrophobicity.

  7. Production of flavor esters catalyzed by CALB-displaying Pichia pastoris whole-cells in a batch reactor.

    PubMed

    Jin, Zi; Ntwali, Janvier; Han, Shuang-Yan; Zheng, Sui-Ping; Lin, Ying

    2012-05-31

    Candida antarctica lipase B (CALB) has been employed as an efficient catalyst in the preparation of many flavor esters. A CALB-displaying yeast whole-cell biocatalyst could be an attractive alternative to commercial immobilized CALB because of its low-cost preparation and high enzymatic activity. We investigated the potential application of CALB-displaying Pichia pastoris cells for the production of flavor esters. The optimal conditions for flavor esters synthesis by this biocatalyst were determined in 50-ml shake flasks. Under optimized conditions, the synthesis of 12 kinds flavor esters were scaled up in a 5-l batch stirred reactor. Among these, the mole conversions of 10 exceeded 95% after reactions for 4h. In addition, this biocatalyst showed good tolerance for high substrates concentration and excellent operational stability. Repeated use of the cells in 10 batches resulted in an activity loss of less than 10%. Thus, CALB-displaying P. pastoris whole cells are robust biocatalysts with potential commercial application in the large-scale production of flavor esters in non-aqueous media. PMID:22410080

  8. Gallic acid and gallic acid derivatives: effects on drug metabolizing enzymes.

    PubMed

    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

  9. Terahertz spectrum of gallic acid

    NASA Astrophysics Data System (ADS)

    Wu, Meng; Zhao, Guozhong; Wang, Haiyan; Liang, Chengshen

    2009-11-01

    Gallic acid is natural polyphenol compound found in many green plants. More and more experiments have demonstrated that the gallic acid has comprehensive applications. In the field of medicine, the gallic acid plays an important role in antianaphylaxis, antineoplastic, antimycotic, anti-inflammatory, antivirotic, antiasthmatic and inhibiting the degradation of insulin. It also has a lot of applications in chemical industry, food industry and light industry. So it is important to study the terahertz time-domain spectroscopy of gallic acid. Terahertz time-domain spectroscopy (THz-TDS) is a new coherent spectral technology based on the femtosecond laser. In this work, the spectral characteristics of gallic acid in the range of 0.4 THz to 2.6 THz have been measured by THz-TDS. We obtained its absorption and refraction spectra at room temperature. The vibration absorption spectrum of the single molecule between 0.4 THz and 2.6 THz is simulated based on the Density Functional Theory (DFT). It is found that the gallic acid has the spectral response to THz wave in this frequency range. The results show the abnormal dispersion at 1.51 THz and 2.05 THz. These results can be used in the qualitative analysis of gallic acid and the medicine and food inspection.

  10. Influence of phenolic compounds on the sensorial perception and volatility of red wine esters in model solution: an insight at the molecular level.

    PubMed

    Lorrain, Bénédicte; Tempere, Sophie; Iturmendi, Nerea; Moine, Virginie; de Revel, Gilles; Teissedre, Pierre-Louis

    2013-09-01

    Impact of (+)-catechin and gallic acid on sensory perception and volatility of isoamyl acetate, ethyl isobutyrate, ethyl butyrate and ethyl octanoate was investigated in model solutions, by means of triangle tests, detection threshold determination and HS-GC-MS analyses. Catechin significantly altered the sensory perception of most esters (ethyl isobutyrate, ethyl butyrate and ethyl octanoate) while gallic acid displayed no impact. Ethyl butyrate and ethyl octanoate odour thresholds doubled or tripled in the presence of catechin, underlining a retention impact of phenolic compounds in liquid matrix. The headspace analyses displayed a decrease only in ethyl octanoate volatility in presence of catechin, whereas no significant difference in other esters concentrations was observed. This study indicated that phenolic compounds have a variable impact on aroma compounds' volatility and their sensory perception. The polarity of phenolic and volatile compounds as well as their spatial conformation also appeared to influence the interaction strength. PMID:23578617

  11. Polyphenols: well beyond the antioxidant capacity: gallic acid and related compounds as neuroprotective agents: you are what you eat!

    PubMed

    Daglia, Maria; Di Lorenzo, Arianna; Nabavi, Seyed F; Talas, Zeliha S; Nabavi, Seyed M

    2014-01-01

    Gallic acid (3,4,5-trihydroxybenzoic acid) is a phenolic acid widely distributed in many different families of higher plants, both in free state, and as a part of more complex molecules, such as ester derivatives or polymers. In nature, gallic acid and its derivatives are present in nearly every part of the plant, such as bark, wood, leaf, fruit, root and seed. They are present in different concentrations in common foodstuffs such as blueberry, blackberry, strawberry, plums, grapes, mango, cashew nut, hazelnut, walnut, tea, wine and so on. After consumption, about 70% of gallic acid is adsorbed and then excreted in the urine as 4-O-methylgallic acid. Differently, the ester derivatives of gallic acid, such as catechin gallate ester or gallotannins, are hydrolyzed to gallic acid before being metabolized to methylated derivatives. Gallic acid is a well known antioxidant compounds which has neuroprotective actions in different models of neurodegeneration, neurotoxicity and oxidative stress. In this review, we discuss about the neuroprotective actions of gallic acid and derivatives and their potential mechanisms of action.

  12. Polyphenols: well beyond the antioxidant capacity: gallic acid and related compounds as neuroprotective agents: you are what you eat!

    PubMed

    Daglia, Maria; Di Lorenzo, Arianna; Nabavi, Seyed F; Talas, Zeliha S; Nabavi, Seyed M

    2014-01-01

    Gallic acid (3,4,5-trihydroxybenzoic acid) is a phenolic acid widely distributed in many different families of higher plants, both in free state, and as a part of more complex molecules, such as ester derivatives or polymers. In nature, gallic acid and its derivatives are present in nearly every part of the plant, such as bark, wood, leaf, fruit, root and seed. They are present in different concentrations in common foodstuffs such as blueberry, blackberry, strawberry, plums, grapes, mango, cashew nut, hazelnut, walnut, tea, wine and so on. After consumption, about 70% of gallic acid is adsorbed and then excreted in the urine as 4-O-methylgallic acid. Differently, the ester derivatives of gallic acid, such as catechin gallate ester or gallotannins, are hydrolyzed to gallic acid before being metabolized to methylated derivatives. Gallic acid is a well known antioxidant compounds which has neuroprotective actions in different models of neurodegeneration, neurotoxicity and oxidative stress. In this review, we discuss about the neuroprotective actions of gallic acid and derivatives and their potential mechanisms of action. PMID:24938889

  13. Gallic acid: molecular rival of cancer.

    PubMed

    Verma, Sharad; Singh, Amit; Mishra, Abha

    2013-05-01

    Gallic acid, a predominant polyphenol, has been shown to inhibit carcinogenesis in animal models and in vitro cancerous cell lines. The inhibitory effect of gallic acid on cancer cell growth is mediated via the modulation of genes which encodes for cell cycle, metastasis, angiogenesis and apoptosis. Gallic acid inhibits activation of NF-κB and Akt signaling pathways along with the activity of COX, ribonucleotide reductase and GSH. Moreover, gallic acid activates ATM kinase signaling pathways to prevent the processes of carcinogenesis. The data so far available, both from in vivo and in vitro studies, indicate that this dietary polyphenol could be promising agent in the field of cancer chemoprevention.

  14. Scaling-up the synthesis of myristate glucose ester catalyzed by a CALB-displaying Pichia pastoris whole-cell biocatalyst.

    PubMed

    Guo, DongHeng; Jin, Zi; Xu, YanShan; Wang, Ping; Lin, Ying; Han, ShuangYan; Zheng, SuiPing

    2015-01-01

    The novel whole-cell biocatalyst Candida antarctica lipase B displaying-Pichia pastoris (Pp-CALB) is characterized by its low preparation cost and could be an alternative to the commercial immobilized Candida antarctica lipase B (CALB). This study addresses the feasibility of using Pp-CALB in large scale glucose fatty acid esters production. 1,2-O-Isopropylidene-α-D-glucofuranose (IpGlc) was used as the acyl acceptor to overcome the low solubility of glucose in an organic solvent and to avoid the addition of toxic co-solvents. IpGlc significantly improved the Pp-CALB catalyzing esterification efficiency when using long chain fatty acids as the acyl donor. Under the preferred operating conditions (50 °C, 40 g/L molecular sieve dosage and 200 rpm mixing intensity), 60.5% of IpGlc converted to 6-O-myristate-1, 2-O-isopropylidene-α-D-glucofuranose (C14-IpGlc) after a 96-h reaction in a 2-L stirred reactor. In a 5-L pilot scale test, Pp-CALB also showed a similar substrate conversion rate of 55.4% and excellent operational stability. After C14-IpGlc was collected, 70% trifluoroacetic acid was adopted to hydrolyze C14-IpGlc to myristate glucose ester (C14-Glc) with a high yield of 95.3%. In conclusion, Pp-CALB is a powerful biocatalyst available for industrial synthesis, and this study describes an applicable and economical process for the large scale production of myristate glucose ester.

  15. Scaling-up the synthesis of myristate glucose ester catalyzed by a CALB-displaying Pichia pastoris whole-cell biocatalyst.

    PubMed

    Guo, DongHeng; Jin, Zi; Xu, YanShan; Wang, Ping; Lin, Ying; Han, ShuangYan; Zheng, SuiPing

    2015-01-01

    The novel whole-cell biocatalyst Candida antarctica lipase B displaying-Pichia pastoris (Pp-CALB) is characterized by its low preparation cost and could be an alternative to the commercial immobilized Candida antarctica lipase B (CALB). This study addresses the feasibility of using Pp-CALB in large scale glucose fatty acid esters production. 1,2-O-Isopropylidene-α-D-glucofuranose (IpGlc) was used as the acyl acceptor to overcome the low solubility of glucose in an organic solvent and to avoid the addition of toxic co-solvents. IpGlc significantly improved the Pp-CALB catalyzing esterification efficiency when using long chain fatty acids as the acyl donor. Under the preferred operating conditions (50 °C, 40 g/L molecular sieve dosage and 200 rpm mixing intensity), 60.5% of IpGlc converted to 6-O-myristate-1, 2-O-isopropylidene-α-D-glucofuranose (C14-IpGlc) after a 96-h reaction in a 2-L stirred reactor. In a 5-L pilot scale test, Pp-CALB also showed a similar substrate conversion rate of 55.4% and excellent operational stability. After C14-IpGlc was collected, 70% trifluoroacetic acid was adopted to hydrolyze C14-IpGlc to myristate glucose ester (C14-Glc) with a high yield of 95.3%. In conclusion, Pp-CALB is a powerful biocatalyst available for industrial synthesis, and this study describes an applicable and economical process for the large scale production of myristate glucose ester. PMID:26047913

  16. Inhibition of fucosyltransferase VII by gallic acid and its derivatives.

    PubMed

    Niu, Xiaoda; Fan, Xuedong; Sun, Jing; Ting, Pauline; Narula, Satwant; Lundell, Daniel

    2004-05-01

    Gallic acid (GA) and several gallate derivatives were identified as inhibitors of fucosyltransferase VII (FucT VII). The inhibition by GA and (-)-epigallocatechin gallate (EGCG) is time-dependent and irreversible. GA and EGCG showed inhibition with IC(50) of 60 and 700 nM, respectively, after pre-incubation with FucT VII in the presence of MnCl(2). Absence of MnCl(2) results in significantly weaker inhibition. Complexation of Mn(2+) with GA, EGCG, and gallate esters was observed. Such complexation, however, is not rate-limiting for the inhibition of FucT VII. Therefore, time-dependent inhibition of fucosyltransferases by GA and EGCG is likely due to the slow inactivation by the inhibitors or Mn-inhibitor complex. Although Mg(2+) or Ca(2+) can replace Mn(2+) for FucT VII activation, none forms a complex with GA or EGCG and hence results in weaker inhibition of FucT VII. GA and EGCG also inhibit FucT IV and alpha2,3-(N)-sialyltransferase in the low micromolar range. The structure-function divergence could be observed, as EGCG, but not GA or gallate esters, inhibits Zn(2+) containing metalloproteases such as TNFalpha convertase, matrix metalloproteases 2 and 7.

  17. Natural flavonoids as antidiabetic agents. The binding of gallic and ellagic acids to glycogen phosphorylase b.

    PubMed

    Kyriakis, Efthimios; Stravodimos, George A; Kantsadi, Anastassia L; Chatzileontiadou, Demetra S M; Skamnaki, Vassiliki T; Leonidas, Demetres D

    2015-07-01

    We present a study on the binding of gallic acid and its dimer ellagic acid to glycogen phosphorylase (GP). Ellagic acid is a potent inhibitor with Kis of 13.4 and 7.5 μM, in contrast to gallic acid which displays Kis of 1.7 and 3.9 mM for GPb and GPa, respectively. Both compounds are competitive inhibitors with respect to the substrate, glucose-1-phoshate, and non-competitive to the allosteric activator, AMP. However, only ellagic acid functions with glucose in a strongly synergistic mode. The crystal structures of the GPb-gallic acid and GPb-ellagic acid complexes were determined at high resolution, revealing that both ligands bind to the inhibitor binding site of the enzyme and highlight the structural basis for the significant difference in their inhibitory potency.

  18. Gallicism, Anglo-Saxonism and Quebec Education.

    ERIC Educational Resources Information Center

    Magnuson, Roger

    1984-01-01

    The current educational debate in Quebec results not only from language, religious, and political differences between English- and French-speaking Quebeckers but also from cultural differences between the Gallic tradition of rationalism, codifed law, and centralism and the Anglo-Saxon tradition of empiricism, common law, and localism. (SB)

  19. Hydrophilic Graphene Preparation from Gallic Acid Modified Graphene Oxide in Magnesium Self-Propagating High Temperature Synthesis Process

    NASA Astrophysics Data System (ADS)

    Cao, Lei; Li, Zhenhuan; Su, Kunmei; Cheng, Bowen

    2016-10-01

    Hydrophilic graphene sheets were synthesized from a mixture of magnesium and gallic acid (GA) modified graphene oxide (GO) in a self-propagating high-temperature synthesis (SHS) process, and hydrophilic graphene sheets displayed the higher C/O ratio (16.36), outstanding conductivity (~88900 S/m) and excellent water-solubility. GO sheets were connected together by GA, and GA was captured to darn GO structure defects through the formation of hydrogen bonds and ester bonds. In SHS process, the most oxygen ions of GO reacted with magnesium to prevent the escape of carbon dioxide and carbon monoxide to from the structure defects associated with vacancies, and GA could take place the high-temperature carbonization, during which a large-area graphene sheets formed with a part of the structure defects being repaired. When only GO was reduced by magnesium in SHS process, and the reduced GO (rGO) exhibited the smaller sheets, the lower C/O ratio (15.26), the weaker conductivity (4200 S/m) and the poor water-solubility because rGO inevitably left behind carbon vacancies and topological defects. Therefore, the larger sheet, less edge defects and free structure defects associated with vacancies play a key role for graphene sheets good dispersion in water.

  20. Hydrophilic Graphene Preparation from Gallic Acid Modified Graphene Oxide in Magnesium Self-Propagating High Temperature Synthesis Process

    PubMed Central

    Cao, Lei; Li, Zhenhuan; Su, Kunmei; Cheng, Bowen

    2016-01-01

    Hydrophilic graphene sheets were synthesized from a mixture of magnesium and gallic acid (GA) modified graphene oxide (GO) in a self-propagating high-temperature synthesis (SHS) process, and hydrophilic graphene sheets displayed the higher C/O ratio (16.36), outstanding conductivity (~88900 S/m) and excellent water-solubility. GO sheets were connected together by GA, and GA was captured to darn GO structure defects through the formation of hydrogen bonds and ester bonds. In SHS process, the most oxygen ions of GO reacted with magnesium to prevent the escape of carbon dioxide and carbon monoxide to from the structure defects associated with vacancies, and GA could take place the high-temperature carbonization, during which a large-area graphene sheets formed with a part of the structure defects being repaired. When only GO was reduced by magnesium in SHS process, and the reduced GO (rGO) exhibited the smaller sheets, the lower C/O ratio (15.26), the weaker conductivity (4200 S/m) and the poor water-solubility because rGO inevitably left behind carbon vacancies and topological defects. Therefore, the larger sheet, less edge defects and free structure defects associated with vacancies play a key role for graphene sheets good dispersion in water. PMID:27725757

  1. The electronic spectral properties of gallic acid

    NASA Astrophysics Data System (ADS)

    Fink, David W.; Stong, John D.

    The electronic spectral properties of gallic acid (3,4,5-trihydroxybenzoic acid), a chemiluminescence reagent which is unstable in oxygenated aqueous solution, have been determined under conditions regulated to retard decomposition. The characteristic blue and red shifts in the u.v. absorption spectra which accompany carboxyl and phenol dissociation, respectively, are in accord with the trends usually observed for these functional groups. The dianionic species exhibits a fluorescence emission band with a peak at 370 nm under 300-nm excitation.

  2. Aqueous thermal degradation of gallic acid

    NASA Astrophysics Data System (ADS)

    Snow Boles, Jennifer; Crerar, David A.; Grissom, Grady; Key, Tonalee C.

    1988-02-01

    Aqueous thermal degradation experiments show gallic acid, a naturally occurring aromatic carboxylic compound, decomposes rapidly at temperatures between 105° and 150°C, with an activation energy of 22.9 or 27.8 kcal/ mole, depending on pH of the starting solution. Pyrogallol is the primary product identified, indicating degradation via decarboxylation and a carbanion transition state. Relatively rapid degradation of vanillic, phthalic, ellagic and tannic acids has also been observed, suggesting that these and perhaps other aromatic acids could be short-lived in deep formation waters.

  3. Aqueous thermal degradation of gallic acid

    SciTech Connect

    Boles, J.S.; Crerar, D.A.; Grissom, G.; Key, T.C.

    1988-02-01

    Aqueous thermal degradation experiments show gallic acid, a naturally occurring aromatic carboxylic compound, decomposes rapidly at temperatures between 105/sup 0/ and 150/sup 0/C, with an activation energy of 22.9 or 27.8 kcal/mole, depending on pH of the starting solution. Pyrogallol is the primary product identified, indicating degradation via decarboxylation and a carbanion transition state. Relatively rapid degradation of vanillic, phthalic, ellagic and tannic acids has also been observed,suggesting that these and perhaps other aromatic acids could be short-lived in deep formation waters.

  4. Oscillations in cytosolic free Ca2+ induced by ADP and ATP in single rat hepatocytes display differential sensitivity to application of phorbol ester.

    PubMed Central

    Dixon, C J; Cobbold, P H; Green, A K

    1995-01-01

    We have previously described differences in the oscillatory responses of cytosolic free Ca2+ concentration ([Ca2+]i) in hepatocytes to ADP and ATP, which we have interpreted as evidence that these two nucleotides are acting at distinct receptors. We show here that ADP- and ATP-induced oscillations are differentially sensitive to application of the phorbol ester 4 beta-phorbol 12,13-dibutyrate (PDB). ADP-induced [Ca2+]i oscillations are abolished by low concentrations of PDB (5-10 nM), whereas ATP-induced oscillations of long duration are refractory to PDB, even at greatly elevated concentrations (100 nM). The data illustrate a further difference in the actions of ADP and ATP, strengthening the argument that these agonists are not acting at the same receptor on rat hepatocytes. PMID:7619050

  5. [Isolation and preparation of gallic acid from Terminalia chebula Retz. with high-speed counter-current chromatography].

    PubMed

    Li, Zhongqin; Li, Qiuyun; Jiang, Xinglong; Zhang, Kun; Guan, Ruizhang

    2014-12-01

    A separation method based on high-speed counter-current chromatography (HSCCC) has been established for the isolation and preparation of gallic acid from the ethanol extract of Terminalia chebula Retz. After comparing five kinds of solvent protocols of HSCCC, the two-phase system of n-hexane-ethyl acetate-methanol-water (1:5:1:5, v/v/v/v) was finally chosen as the operating solvent of HSCCC for the separation of gallic acid, in which the lower phase was used as the mobile phase and the upper phase as stationary phase. The detection in the experiments was performed with an ultraviolet detector at 254 nm. Under the conditions of rotation speed of 850 r/min, lower phase flow rate of 2 mL/min, four peaks (I/II/III/IV) were displayed on HSCCC chromatogram. Among them, only peak III contained a large amount of gallic acid (about 96. 40%), which was confirmed by electrospray ionization mass spectrometry (ESI-MS) and high performance liquid chromatographic (HPLC) analysis. As much as 8. 6 mg of gallic acid was obtained from 100 mg of the ethanol extract of Terminalia chebula Retz., indicating the method is simple, robust and efficient for the preparation of gallic acid.

  6. Cosmetotextiles with Gallic Acid: Skin Reservoir Effect

    PubMed Central

    Alonso, Cristina; Martínez, Vanessa; Lis, Manel; de la Maza, Alfons; Parra, José L.; Coderch, Luisa

    2013-01-01

    The antioxidant gallic acid (GA) has been incorporated into cotton (CO) and polyamide (PA) through two different vehicles, that is, liposomes and mixed micelles, and their respective absorption/desorption processes have been studied. Moreover, in vitro percutaneous absorption tests of different cosmetotextiles have been performed to demonstrate antioxidant penetration within the layers of the skin. When GA was embedded into the cosmetotextiles, it always promoted a reservoir effect that was much more marked than that observed for polyamide. Similar penetration was observed in the textiles treated with GA in mixed micelles or liposomes in such compartments of the skin as the stratum corneum, epidermis, and even the dermis. GA was detected in receptor fluid only when CO was treated with MM. This methodology may be useful in verifying how encapsulated substances incorporated into textile materials penetrate human skin. Indeed, such materials can be considered strategic delivery systems that release a given active compound into the skin at specific doses. PMID:23691326

  7. Density functional theory calculations on dipeptide gallic acid interaction

    NASA Astrophysics Data System (ADS)

    Madhan, B.; Parthasarathi, R.; Subramanian, V.; Raghava Rao, J.; Nair, Balachandran Unni; Ramasami, T.

    2003-02-01

    In the present investigation, an attempt has been made to study the interaction of dipeptides with gallic acid, using Becke3 parameter Lee Yang Parr (B3LYP) method employing 3-21G*, 6-31G* and 6-31+G* basis sets. The interaction energies of the dipeptide-gallic acid complexes are in the range of -5 to -18 kcal/mol depending on the mode of intermolecular complexation. Calculated molecular electrostatic potential (MESP) for the various intermolecular complexes revealed the electrostatic nature of the interaction. Qualitative estimations based on chemical hardness and chemical potential demonstrated fractional electron transfer from dipeptide to gallic acid.

  8. Gallic Acid: Review of the Methods of Determination and Quantification.

    PubMed

    Fernandes, Felipe Hugo Alencar; Salgado, Hérida Regina Nunes

    2016-05-01

    Gallic acid (3,4,5 trihydroxybenzoic acid) is a secondary metabolite present in most plants. This metabolite is known to exhibit a range of bioactivities including antioxidant, antimicrobial, anti-inflammatory, and anticancer. There are various methods to analyze gallic acid including spectrometry, chromatography, and capillary electrophoresis, among others. They have been developed to identify and quantify this active ingredient in most biological matrices. The aim of this article is to review the available information on analytical methods for gallic acid, as well as presenting the advantages and limitations of each technique.

  9. Neuroprotective effects of green and black teas and their catechin gallate esters against beta-amyloid-induced toxicity.

    PubMed

    Bastianetto, Stéphane; Yao, Zhi-Xing; Papadopoulos, Vassilios; Quirion, Rémi

    2006-01-01

    Teas represent a large family of plants containing high amounts of polyphenols that may confer health benefits in various diseases. Recently, it has been hypothesized that tea consumption may also reduce the risk of age-related neurodegenerative pathologies. Considering the deleterious role of beta-amyloid (Abeta) in the aetiology of Alzheimer's disease (AD), we investigated green and black tea extracts and flavan-3-ols (present as monomers and dimers in green and black forms, respectively) against toxicity induced by Abeta-derived peptides using primary cultures of rat hippocampal cells as model. Both green and black tea extracts (5-25 microg/mL) displayed neuroprotective action against Abeta toxicity. These effects were shared by gallic acid (1-20 microm), epicatechin gallate (ECG; 1-20 microM) and epigallocatechin gallate (EGCG; 1-10 microM), the former being the most potent flavan-3-ol. In contrast, epicatechin and epigallocatechin were ineffective in the same range of concentrations. Moreover, only tea flavan-3-ol gallate esters (i.e. ECG, EGCG) and gallic acid inhibited apoptotic events induced by Abeta(25-35). Interestingly, EGCG and gallic acid inhibited Abeta aggregation and/or the formation of Abeta-derived diffusible neurotoxin ligands. Taken together, these results indicate that the catechin gallates (through the galloyl moiety) contribute to the neuroprotective effects of both green and black teas. Moreover, the protective effect of EGCG is likely to be associated, at least in part, with its inhibitory action on Abeta fibrils/oligomers formation. These data also support the hypothesis that not only green but also black teas may reduce age-related neurodegenerative diseases, such as AD.

  10. A new approach to microbial production of gallic acid

    PubMed Central

    Bajpai, Bhakti; Patil, Shridhar

    2008-01-01

    In a new approach to microbial gallic acid production by Aspergillus fischeri MTCC 150, 40gL−1 of tannic acid was added in two installments during the bioconversion phase of the process (25gL−1 and 15gL−1 at 32 and 44h respectively). The optimum parameters for the bioconversion phase were found to be temperature: 35°C, pH: slightly acidic (3.3–3.5), aeration: nil and agitation: 250 rpm. A maximum of 71.4% conversion was obtained after 71h fermentation with 83.3% product recovery. The yield was 7.35 g of gallic acid per g of biomass accumulated and the fermenter productivity was 0.56 g of gallic acid produced per liter of medium per hour. PMID:24031294

  11. REPRODUCTIVE TOXICITY OF PHTHALATE ESTERS

    EPA Science Inventory

    Phthalate esters display several modes of toxicity in mammalian species. In the rat, in utero exposure at relatively low dosage levels disrupts development of the reproductive system of the male rat by altering fetal testis hormone production. This presentation is a review of t...

  12. [Mutagenic activity of organic esters are likely to form from bromo-2 ethanol generated during fumigation using ethylene oxide].

    PubMed

    Min, S; Chaigneau, M; Callais, F; Festy, B

    1989-01-01

    The mutagenic potencies of 13 bromoethyl esters of natural organic acids, have been studied, by Ames's test (strains TA 98 and TA 100, with and without system of metabolisation, S9 mix). None of the 8 bromoethyl esters of linoleic, oleic, palmitic, stearic, lauric, myristic, cinnamic and fumaric acids is genotoxic. On the other hand the 5 others derived from gallic, oxalic, tartric acids (strain TA 100 with and without S9 mix), malic and citric acids (strain TA 100 with S9 mix) are mutagenic, the ester of gallic acid giving still a doubtful mutagenic response; their mutagenic potencies are 2 to 3 times smaller than that of bromo-2 ethanol. This observation, complemently with the mutagenicity of some organic esters of the chloro-2 ethanol, proves the potential danger of ethylene oxide used for the fumigation of foods or vegetables and medicinal plants containing much chloride and/or bromide.

  13. Influence of gallic acid esters on drug-metabolizing enzymes of rat liver.

    PubMed

    Depner, M; Kahl, G F; Kahl, R

    1982-10-01

    The effect of three antioxidants, propyl, octyl and dodecyl gallate, on hepatic drug metabolism in male rats was studied in vivo and in vitro. When fed at a dietary concentration of 1% for 14 days, only dodecyl gallate increased relative liver weight. Cytochrome P-450 content was not influenced, but a slight increase in cytochrome b5 content was observed after the feeding of propyl gallate. Monooxygenase activity (benzo[a]pyrene-hydroxylase and ethoxycoumarin-deethylase activities) was not affected by propyl or octyl gallate, but a significant decrease in benzo[a]pyrene-hydroxylase activity was apparent in rats fed dodecyl gallate. Study of benzo[a]pyrene-metabolite formation in liver microsome preparations from control and propyl gallate-treated rats showed an overall decrease in metabolite production following gallate treatment, the decrease being statistically significant for the formation of the 9,10-dihydrodiol. Epoxide-hydratase activity was enhanced by a factor of 1.5 in rats fed propyl gallate; glutathione-transferase activity was unaffected. In vitro, the gallates proved to be potent inhibitors of ethoxycoumarin deethylation in liver microsomes from untreated and phenobarbital-treated rats; however, when cytochrome P-448 had been induced by pretreatment with 3-methylcholanthrene, ethoxycoumarin deethylase was less sensitive to the inhibitory action of the gallates.

  14. Effects of 2,3-Dehydrosilybin and Its Galloyl Ester and Methyl Ether Derivatives on Human Umbilical Vein Endothelial Cells.

    PubMed

    Karas, Daniel; Gažák, Radek; Valentová, Kateřina; Chambers, Christopher S; Pivodová, Veronika; Biedermann, David; Křenková, Alena; Oborná, Ivana; Kuzma, Marek; Cvačka, Josef; Ulrichová, Jitka; Křen, Vladimír

    2016-04-22

    The effects in vitro of 2,3-dehydrosilybin and several galloyl esters and methyl ethers on the viability, proliferation, and migration of human umbilical vein endothelial cells (HUVECs) were evaluated. The monogalloyl esters were synthesized by a chemoselective esterification method or by Steglich esterification of suitably protected 2,3-dehydrosilybin (1) with protected gallic acid. 2,3-Dehydrosilybin (1) displayed more potent cytotoxic, antiproliferative, and antimigratory activities (IC50 12.0, 5.4, and 12.2 μM, respectively) than silybin. The methylated derivatives were less active, with the least potent being 3,7-di-O-methyl-2,3-dehydrosilybin (6). On the other hand, galloylation at C-7 OH and C-23 OH markedly increased the cytotoxicity and the effects on the proliferation and migration of HUVECs. The most active derivative was 7-O-galloyl-2,3-dehydrosilybin (13; IC50 value of 3.4, 1.6, and 4.7 μM in the cytotoxicity, inhibition of proliferation, and antimigratory assays, respectively). Overall, this preliminary structure-activity relationship study demonstrated the importance of a 2,3-double bond, a C-7 OH group, and a galloyl moiety in enhancing the activity of flavonolignans toward HUVECs.

  15. Antiradical activity of gallic acid included in lipid interphases.

    PubMed

    Salcedo, C L; Frías, M A; Cutro, A C; Nazareno, M A; Disalvo, E A

    2014-10-01

    Polyphenols are well known as antioxidant agents and by their effects on the hydration layers of lipid interphases. Among them, gallic acid and its derivatives are able to decrease the dipole potential and to act in water as a strong antioxidant. In this work we have studied both effects on lipid interphases in monolayers and bilayers of dimyristoylphosphatidylcholine. The results show that gallic acid (GA) increases the negative surface charges of large unilamellar vesicles (LUVs) and decreases the dipole potential of the lipid interphase. As a result, positively charged radical species such as ABTS(+) are able to penetrate the membrane forming an association with GA. These results allow discussing the antiradical activity (ARA) of GA at the membrane phase which may be taking place in water spaces between the lipids.

  16. The impact of gallic acid on iron gall ink corrosion

    NASA Astrophysics Data System (ADS)

    Rouchon-Quillet, V.; Remazeilles, C.; Bernard, J.; Wattiaux, A.; Fournes, L.

    Many old manuscripts suffer from iron-gall ink corrosion, threatening our graphic heritage. Corroded papers become brown and brittle with age. The chemical reactions involved in this corrosion are relatively well known: they include both acidic hydrolysis and oxidation catalysed by free iron(II). Yet, a great variety of iron-gall ink recipes, including a wide range of constituents can be found in the literature and the visual aspect of old inks, can be very different from one inscription to another, even if they have been written on the same sheet of paper. This suggests that even if the free iron(II) plays a dominant role in the paper alteration, the contribution of other ingredients should not be neglected. For this reason, we explored the impact gallic acid may have on the corrosion mechanisms and in particular on the oxidation reactions. These investigations were carried out on laboratory probes prepared with paper sheets immersed in different solutions, all containing the same amount of iron sulphate, and different gallic acid concentrations. These probes were then artificially aged and their degradation state was evaluated by bursting strength measurements, FTIR spectrometry and Mössbauer spectrometry. All these analyses lead us to conclude that gallic acid has an influence on the iron(III)/iron(II) ratio, probably because of its reducing properties.

  17. Evidence does not support a role for gallic acid in Phragmites australis invasion success.

    PubMed

    Weidenhamer, Jeffrey D; Li, Mei; Allman, Joshua; Bergosh, Robert G; Posner, Mason

    2013-02-01

    Gallic acid has been reported to be responsible for the invasive success of nonnative genotypes of Phragmites australis in North America. We have been unable to confirm previous reports of persistent high concentrations of gallic acid in the rhizosphere of invasive P. australis, and of high concentrations of gallic acid and gallotannins in P. australis rhizomes. The half-life of gallic acid in nonsterile P. australis soil was measured by aqueous extraction of soils and found to be less than 1 day at added concentrations up to 10,000 μg g(-1). Furthermore, extraction of P. australis soil collected in North Carolina showed no evidence of gallic acid, and extractions of both rhizomes and leaves of samples of four P. australis populations confirmed to be of invasive genotype show only trace amounts of gallic acid and/or gallotannins. The detection limits were less than 20 μg gallic acid g(-1) FW in the rhizome samples tested, which is approximately 0.015 % of the minimum amount of gallic acid expected based on previous reports. While the occurrence of high concentrations of gallic acid and gallotannins in some local populations of P. australis cannot be ruled out, our results indicate that exudation of gallic acid by P. australis cannot be a primary, general explanation for the invasive success of this species in North America.

  18. Gallic acid isolated from Spirogyra sp. improves cardiovascular disease through a vasorelaxant and antihypertensive effect.

    PubMed

    Kang, Nalae; Lee, Ji-Hyeok; Lee, WonWoo; Ko, Ju-Young; Kim, Eun-A; Kim, Jin-Soo; Heu, Min-Soo; Kim, Gwang Hoon; Jeon, You-Jin

    2015-03-01

    In this study, we investigated the vasorelaxant and antihypertensive effects of gallic acid (GA), a polyphenol isolated from the green alga Spirogyra sp., to assess its suitability as a therapeutic for cardiovascular diseases (CVDs). We examined the effect of GA on endothelium-dependent vasorelaxation in human umbilical vein endothelial cells (HUVECs). GA increased nitric oxide (NO) levels by increasing phosphorylation of endothelial nitric oxide synthase (eNOS), and its effect on NO production was attenuated by pretreatment with the eNOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We also investigated its antihypertensive effect by examining GA-mediated inhibition of angiotensin-I converting enzyme (ACE). GA inhibited ACE with a half-maximal inhibitory concentration (IC50) value of 37.38 ± 0.39 μg/ml. In silico simulations revealed that GA binds to the active site of ACE (PDB: 1O86) with a binding energy of -270.487 kcal/mol. Furthermore, GA clearly reduced blood pressure in spontaneously hypertensive rats (SHR) to an extent comparable to captopril. These results suggest that GA isolated from Spirogyra sp. exerts multiple therapeutic effects and has potential as a CVD treatment. PMID:25727171

  19. Gallic acid isolated from Spirogyra sp. improves cardiovascular disease through a vasorelaxant and antihypertensive effect.

    PubMed

    Kang, Nalae; Lee, Ji-Hyeok; Lee, WonWoo; Ko, Ju-Young; Kim, Eun-A; Kim, Jin-Soo; Heu, Min-Soo; Kim, Gwang Hoon; Jeon, You-Jin

    2015-03-01

    In this study, we investigated the vasorelaxant and antihypertensive effects of gallic acid (GA), a polyphenol isolated from the green alga Spirogyra sp., to assess its suitability as a therapeutic for cardiovascular diseases (CVDs). We examined the effect of GA on endothelium-dependent vasorelaxation in human umbilical vein endothelial cells (HUVECs). GA increased nitric oxide (NO) levels by increasing phosphorylation of endothelial nitric oxide synthase (eNOS), and its effect on NO production was attenuated by pretreatment with the eNOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We also investigated its antihypertensive effect by examining GA-mediated inhibition of angiotensin-I converting enzyme (ACE). GA inhibited ACE with a half-maximal inhibitory concentration (IC50) value of 37.38 ± 0.39 μg/ml. In silico simulations revealed that GA binds to the active site of ACE (PDB: 1O86) with a binding energy of -270.487 kcal/mol. Furthermore, GA clearly reduced blood pressure in spontaneously hypertensive rats (SHR) to an extent comparable to captopril. These results suggest that GA isolated from Spirogyra sp. exerts multiple therapeutic effects and has potential as a CVD treatment.

  20. Gallic acid reduces cell viability, proliferation, invasion and angiogenesis in human cervical cancer cells

    PubMed Central

    ZHAO, BING; HU, MENGCAI

    2013-01-01

    Gallic acid is a trihydroxybenzoic acid, also known as 3,4,5-trihydroxybenzoic acid, which is present in plants worldwide, including Chinese medicinal herbs. Gallic acid has been shown to have cytotoxic effects in certain cancer cells, without damaging normal cells. The objective of the present study was to determine whether gallic acid is able to inhibit human cervical cancer cell viability, proliferation and invasion and suppress cervical cancer cell-mediated angiogenesis. Treatment of HeLa and HTB-35 human cancer cells with gallic acid decreased cell viability in a dose-dependent manner. BrdU proliferation and tube formation assays indicated that gallic acid significantly decreased human cervical cancer cell proliferation and tube formation in human umbilical vein endothelial cells, respectively. Additionally, gallic acid decreased HeLa and HTB-35 cell invasion in vitro. Western blot analysis demonstrated that the expression of ADAM17, EGFR, p-Akt and p-Erk was suppressed by gallic acid in the HeLa and HTB-35 cell lines. These data indicate that the suppression of ADAM17 and the downregulation of the EGFR, Akt/p-Akt and Erk/p-Erk signaling pathways may contribute to the suppression of cancer progression by Gallic acid. Gallic acid may be a valuable candidate for the treatment of cervical cancer. PMID:24843386

  1. Gallic Acid, Ellagic Acid and Pyrogallol Reaction with Metallic Iron

    NASA Astrophysics Data System (ADS)

    Jaén, J. A.; González, L.; Vargas, A.; Olave, G.

    2003-06-01

    The reaction between gallic acid, ellagic acid and pyrogallol with metallic iron was studied using infrared and Mössbauer spectroscopy. Most hydrolysable tannins with interesting anticorrosive or inhibition properties are structurally related to these compounds, thus they may be used as models for the study of hydrolysable tannins and related polyphenols. The interaction was followed up to 3 months. Results indicated two different behaviors. At polyphenol concentrations higher than 1% iron converts to sparingly soluble and amorphous ferric (and ferrous) polyphenolate complexes. At lower concentrations (0.1%), the hydrolysis reactions are dominant, resulting in the formation of oxyhydroxides, which can be further reduced to compounds like magnetite by the polyphenols.

  2. Gallic acid-based indanone derivatives as anticancer agents.

    PubMed

    Saxena, Hari Om; Faridi, Uzma; Srivastava, Suchita; Kumar, J K; Darokar, M P; Luqman, Suaib; Chanotiya, C S; Krishna, Vinay; Negi, Arvind S; Khanuja, S P S

    2008-07-15

    Gallic acid-based indanone derivatives have been synthesised. Some of the indanones showed very good anticancer activity in MTT assay. Compounds 10, 11, 12 and 14 possessed potent anticancer activity against various human cancer cell lines. The most potent indanone (10, IC(50)=2.2 microM), against MCF-7, that is, hormone-dependent breast cancer cell line, showed no toxicity to human erythrocytes even at higher concentrations (100 microg/ml, 258 microM). While, indanones 11, 12 and 14 showed toxicities to erythrocytes at higher concentrations.

  3. Design of chitosan-based nanoparticles functionalized with gallic acid.

    PubMed

    Lamarra, J; Rivero, S; Pinotti, A

    2016-10-01

    Active nanoparticles based on chitosan could be applied as a support for the modulation of gallic acid delivery. In this sense, these nanostructures could be employed in different fields such as food, packaging, and pharmaceutical areas. The design parameters of chitosan-based nanoparticles functionalized with gallic acid (GA) were optimized through RSM by means of the analysis of zeta potential (ZP) and percentage encapsulation efficiency (PEE). The nanoparticles were prepared by ionotropic gelation using tripolyphosphate (TPP), at different combinations of chitosan (CH) concentration, CH:TPP ratio and GA. Global desirability methodology allowed finding the optimum formulation that included CH 0.76% (w/w), CH:TPP ratio of 5 and 37mgGA/gCH leading to ZP of +50mV and 82% of PEE. Analysis through QuickScan and turbidity demonstrated that the most stable nanoparticle suspensions were achieved combining concentrations of chitosan ranging between 0.5 and 0.75% with CH:TPP ratios higher than 3. These suspensions had high stability confirmed by means ZP and transmittance values which were higher than +25mV and 0.21 on average, respectively, as well as nanoparticle diameters of about 140nm. FTIR revealed the occurrence of both hydrogen bond and ionic interactions of CH-TPP which allowed the encapsulation and the improvement of the stability of the active agent. PMID:27287172

  4. The fifth solvatomorph of gallic acid with a supramolecular channel structure: Structural complexity and phase transitions

    NASA Astrophysics Data System (ADS)

    Thomas, Sajesh P.; Kaur, Ramanpreet; Kaur, Jassjot; Sankolli, Ravish; Nayak, Susanta K.; Guru Row, Tayur N.

    2013-01-01

    A new solvatomorph of gallic acid was generated using chiral additive technique and characterized by single crystal and powder X-ray diffraction, C-13 NMR, IR spectroscopic techniques and thermal analysis. The supramolecular channels formed by hexameric motifs of gallic acid and solvent molecules contain highly disordered solvent molecules with fractional occupancies.

  5. Gallic acid suppresses cell viability, proliferation, invasion and angiogenesis in human glioma cells

    PubMed Central

    Lu, Yong; Jiang, Feng; Jiang, Hao; Wu, Kalina; Zheng, Xuguang; Cai, Yizhong; Katakowski, Mark; Chopp, Michael; To, Shing-Shun Tony

    2010-01-01

    Gallic acid, an organic acid, also known as 3,4,5-trihydroxybenzoic acid, is cytotoxic against certain cancer cells, without harming normal cells. The objective of this study is to evaluate whether gallic acid can inhibit glioma cell viability, proliferation, invasion and reduce glioma cell mediated angiogenesis. Treatment of U87 and U251n glioma cells with gallic acid inhibited cell viability in a dose- and time-dependent manner. BrdU and tube formation assays indicated that gallic acid significantly decreased glioma cell proliferation and tube formation in mouse brain endothelial cells, respectively. In addition, gallic acid decreased U87 cell invasion in vitro. Western blot analysis showed that expression of ADAM17, p-Akt and p-Erk was suppressed by gallic acid in both U87 and U251n cell lines. These data suggest that suppression of ADAM17 and downregulation of PI3K/Akt and Ras/MAPK signaling pathways may contribute to gallic acid-induced decrease of invasiveness. Gallic acid may be a valuable candidate for treatment of brain tumor. PMID:20553913

  6. Gallic acid-grafted-chitosan inhibits foodborne pathogens by a membrane damage mechanism.

    PubMed

    Lee, Dae-Sung; Je, Jae-Young

    2013-07-01

    In this study, antimicrobial activity of gallic acid-grafted-chitosans (gallic acid-g-chitosans) against five Gram-positive and five Gram-negative foodborne pathogens was evaluated. The minimum inhibitory concentrations (MICs) of gallic acid-g-chitosans ranged from 16 to 64 μg/mL against Gram-positive bacteria and ranged from 128 to 512 μg/mL against Gram-negative bacteria. These activities were higher than those of unmodified chitosan. The bactericidal activity of gallic acid-g-chitosan (I), which showed the highest antimicrobial activity, was evaluated by time-killing assay with multiples of MIC, and it was recognized to depend on its dose. The integrity of cell membrane, outer membrane (OM), inner membrane (IM) permeabilization experiments, and transmission electron microscopy (TEM) observation were conducted for elucidation of the detailed antimicrobial mode of action of gallic acid-g-chitosan. Results showed that treatment of gallic acid-g-chitosan (I) quickly increased the release of intracellular components for both Escherichia coli and Staphylococcus aureus. In addition, gallic acid-g-chitosan (I) also rapidly increased the 1-N-phenylanphthylamine (NPN) uptake and the release of β-galactosidase via increasing the permeability of OM and IM in E. coli. TEM observation demonstrated that gallic acid-g-chitosan (I) killed the bacteria via disrupting the cell membrane.

  7. Prophylactic Antioxidant Potential of Gallic Acid in Murine Model of Sepsis

    PubMed Central

    Maurya, Harikesh; Mangal, Vaishali; Gandhi, Sanjay; Prabhu, Kathiresan; Ponnudurai, Kathiresan

    2014-01-01

    Present study is to investigate the effect of Gallic acid pretreatment on survival of septic animals and oxidative stress in different organs like lungs, liver, kidney, spleen, and vascular dysfunction of mice. Sepsis was induced by cecal ligation and puncture (CLP) in healthy adult male albino mice (25–30 g) and was divided into 3 groups each consisting of 6 animals, that is, sham-operated (SO group (Group I), SO + sepsis (Group II), and Gallic acid + sepsis (Group III)). Group III animals were pretreated with Gallic acid at the dose rate of 20 mg/kg body weight for 2 days before induction of sepsis. Animals were sacrificed on 8th day and the tissue samples were obtained for further investigation on lipid peroxidation (LPO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GSH). Gallic acid pretreatment significant (P < 0.05) reduces kidney, spleen, liver, and lungs' malondialdehyde level in septic mice. However, it fails to improve reduced glutathione level in all given organs, while, Gallic acid pretreated mice showed significant improvement in SOD activity of kidney and spleen when compared to septic mice. Finally, the beneficial effects of Gallic acid pretreatment in sepsis are evident from the observations that Gallic acid partially restored SOD and catalase activity and completely reversed lipid peroxidation. Further studies are required to find out the possible mechanisms underlying the beneficial effects of Gallic acid on large population. PMID:25018890

  8. ESTER: Evolution STEllaire en Rotation

    NASA Astrophysics Data System (ADS)

    Rieutord, Michel

    2013-05-01

    The ESTER code computes the steady state of an isolated star of mass larger than two solar masses. The only convective region computed as such is the core where isentropy is assumed. ESTER provides solutions of the partial differential equations, for the pressure, density, temperature, angular velocity and meridional velocity for the whole volume. The angular velocity (differential rotation) and meridional circulation are computed consistently with the structure and are driven by the baroclinic torque. The code uses spectral methods, both radially and horizontally, with spherical harmonics and Chebyshev polynomials. The iterations follow Newton's algorithm. The code is object-oriented and is written in C++; a python suite allows an easy visualization of the results. While running, PGPLOT graphs are displayed to show evolution of the iterations.

  9. Textiles with gallic acid microspheres: in vitro release characteristics.

    PubMed

    Martí, Meritxell; Martínez, Vanessa; Carreras, Núria; Alonso, Cristina; Lis, Manuel José; Parra, José Luis; Coderch, Luisa

    2014-01-01

    Abstract The aim of this study was to demonstrate the skin penetration of an antioxidant, gallic acid (GA), encapsulated in poly-ε-caprolactone (PCL) microspheres and applied onto textile fabrics, by a specific in vitro percutaneous absorption methodology. Two techniques (particle size distribution and FTIR) were used to characterise the microspheres obtained. The amount of GA-loaded microspheres present in the biofunctional textiles was established before their use as a textile drug delivery system. More absorption and desorption of microspheres with GA for the polyamide fabric were found in comparison with cotton fabric. The percutaneous absorption results indicated that the skin penetration of GA released from PCL-microspheres that were applied directly to the skin was higher than when GA was embedded within biofunctional textiles, in conclusion, an interesting reservoir effect may be promoted when biofunctional textiles were used.

  10. Nanoencapsulation of gallic acid and evaluation of its cytotoxicity and antioxidant activity.

    PubMed

    de Cristo Soares Alves, Aline; Mainardes, Rubiana Mara; Khalil, Najeh Maissar

    2016-03-01

    Gallic acid is an important polyphenol compound presenting various biological activities. The objective of this study was to prepare, characterize and evaluate poly(lactic-co-glycolic acid) (PLGA) nanoparticles coated or not with polysorbate 80 (PS80) containing gallic acid. Nanoparticles coated or not with PS80 were produced by emulsion solvent evaporation method and presented a mean size of around 225 nm, gallic acid encapsulation efficiency of around 26% and zeta potential of -22 mV. Nanoparticle formulations were stable during storage, except nanoparticles coated with PS80 stored at room temperature. In vitro release profile demonstrated a quite sustained gallic acid release from nanoparticles and PS80-coating decreased drug release. Cytotoxicity over red blood cells was assessed and gallic acid-loaded PLGA nanoparticles at all analyzed concentrations demonstrated lack of hemolysis, while PS80-nanoparticles containing gallic acid were cytotoxic only in higher concentrations. Antioxidant potential of nanoparticles containing gallic acid was assessed and PLGA uncoated nanoparticles presented greater efficacy than PS80-coated PLGA nanoparticles.

  11. Gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancers by accelerating EGFR turnover.

    PubMed

    Nam, Boas; Rho, Jin Kyung; Shin, Dong-Myung; Son, Jaekyoung

    2016-10-01

    Gallic acid is a common botanic phenolic compound, which is present in plants and foods worldwide. Gallic acid is implicated in various biological processes such as cell growth and apoptosis. Indeed, gallic acid has been shown to induce apoptosis in many cancer types. However, the molecular mechanisms of gallic acid-induced apoptosis in cancer, particularly lung cancer, are still unclear. Here, we report that gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancer (NSCLC) cells, but not in EGFR-WT NSCLC cells. Treatment with gallic acid resulted in a significant reduction in proliferation and induction of apoptosis, only in EGFR-mutant NSCLC cells. Interestingly, treatment with gallic acid led to a robust decrease in EGFR levels, which is critical for NSCLC survival. Treatment with gallic acid had no significant effect on transcription, but induced EGFR turnover. Indeed, treatment with a proteasome inhibitor dramatically reversed gallic acid-induced EGFR downregulation. Moreover, treatment with gallic acid induced EGFR turnover leading to apoptosis in EGFR-TKI (tyrosine kinase inhibitor)-resistant cell lines, which are dependent on EGFR signaling for survival. Thus, these studies suggest that gallic acid can induce apoptosis in EGFR-dependent lung cancers that are dependent on EGFR for growth and survival via acceleration of EGFR turnover.

  12. Gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancers by accelerating EGFR turnover.

    PubMed

    Nam, Boas; Rho, Jin Kyung; Shin, Dong-Myung; Son, Jaekyoung

    2016-10-01

    Gallic acid is a common botanic phenolic compound, which is present in plants and foods worldwide. Gallic acid is implicated in various biological processes such as cell growth and apoptosis. Indeed, gallic acid has been shown to induce apoptosis in many cancer types. However, the molecular mechanisms of gallic acid-induced apoptosis in cancer, particularly lung cancer, are still unclear. Here, we report that gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancer (NSCLC) cells, but not in EGFR-WT NSCLC cells. Treatment with gallic acid resulted in a significant reduction in proliferation and induction of apoptosis, only in EGFR-mutant NSCLC cells. Interestingly, treatment with gallic acid led to a robust decrease in EGFR levels, which is critical for NSCLC survival. Treatment with gallic acid had no significant effect on transcription, but induced EGFR turnover. Indeed, treatment with a proteasome inhibitor dramatically reversed gallic acid-induced EGFR downregulation. Moreover, treatment with gallic acid induced EGFR turnover leading to apoptosis in EGFR-TKI (tyrosine kinase inhibitor)-resistant cell lines, which are dependent on EGFR signaling for survival. Thus, these studies suggest that gallic acid can induce apoptosis in EGFR-dependent lung cancers that are dependent on EGFR for growth and survival via acceleration of EGFR turnover. PMID:27597244

  13. Induction of apoptosis by gallic acid in human stomach cancer KATO III and colon adenocarcinoma COLO 205 cell lines.

    PubMed

    Yoshioka, K; Kataoka, T; Hayashi, T; Hasegawa, M; Ishi, Y; Hibasami, H

    2000-01-01

    Antitumor effects of gallic acid on human stomach cancer KATO III cells and human colon adenocarcinoma COLO 205 cells were investigated. The exposures of KATO III and COLO 205 cells to gallic acid led to both growth inhibition and induction of apoptosis. Morphological changes showing apoptotic bodies were observed in both the cell lines treated with gallic acid. The fragmentations by gallic acid of DNA to oligonucleosomal-sized fragments, that are characteristics of apoptosis, were observed to be concentration- and time-dependent. These findings suggest that growth inhibitions by gallic acid of KATO III cells and COLO 205 cells result from the apoptosis induced by gallic acid. Thus, gallic acid might be a candidate drug for digestive gut cancer treatment to overcome the resistance to chemotherapeutic drugs. PMID:11032918

  14. Ferulic acid esters and weight-loss promoting effects in rats.

    PubMed

    Totani, Nagao; Tateishi, Sayuri; Takimoto, Tatsuya; Shinohara, Risa; Sasaki, Hideaki

    2012-01-01

    We previously fed rats with an ester (90 ppm in a powdered AIN93G diet) synthesized from gallic acid and 1,2-dioleoyl glycerol and found that it promoted weight loss more effectively than either octyl gallate or gallic acid. Here, we esterified ferulic acid (FerA) with oleic acid, monooleoyl glycerol and dioleoyl glycerol to obtain oleoyl ferulic acid (FO), feruloyl monooleoyl glycerol (FMO) and feruloyl dioleoyl glycerol (FDO) esters, respectively. A mixture of AIN93G and 90 ppm of each ester and FerA was fed to 10-week-old male Wistar rats for 12 weeks. The FMO and FDO groups weighed less than the control group starting from approximately 16 weeks of age. At 21 and 22 weeks of age, weight significantly differed between the FMO and both groups, respectively, and controls. The FO, FerA and control groups did not significantly differ in terms of body, liver, kidney and retroperitoneal fat tissue weights and serum biochemical findings. We concluded that the hydroxyl group of FerA is essential for promoting weight loss and that the carboxyl group should be esterified with alcohol. In addition, monooleoyl glycerol and dioleoyl glycerol did not show any difference as the alcohol moiety of the ester in the weight loss effect. PMID:22687778

  15. Ferulic acid esters and weight-loss promoting effects in rats.

    PubMed

    Totani, Nagao; Tateishi, Sayuri; Takimoto, Tatsuya; Shinohara, Risa; Sasaki, Hideaki

    2012-01-01

    We previously fed rats with an ester (90 ppm in a powdered AIN93G diet) synthesized from gallic acid and 1,2-dioleoyl glycerol and found that it promoted weight loss more effectively than either octyl gallate or gallic acid. Here, we esterified ferulic acid (FerA) with oleic acid, monooleoyl glycerol and dioleoyl glycerol to obtain oleoyl ferulic acid (FO), feruloyl monooleoyl glycerol (FMO) and feruloyl dioleoyl glycerol (FDO) esters, respectively. A mixture of AIN93G and 90 ppm of each ester and FerA was fed to 10-week-old male Wistar rats for 12 weeks. The FMO and FDO groups weighed less than the control group starting from approximately 16 weeks of age. At 21 and 22 weeks of age, weight significantly differed between the FMO and both groups, respectively, and controls. The FO, FerA and control groups did not significantly differ in terms of body, liver, kidney and retroperitoneal fat tissue weights and serum biochemical findings. We concluded that the hydroxyl group of FerA is essential for promoting weight loss and that the carboxyl group should be esterified with alcohol. In addition, monooleoyl glycerol and dioleoyl glycerol did not show any difference as the alcohol moiety of the ester in the weight loss effect.

  16. Liquid crystalline thermosets from ester, ester-imide, and ester-amide oligomers

    NASA Technical Reports Server (NTRS)

    Dingemans, Theodorous J. (Inventor); Weiser, Erik S. (Inventor); St. Clair, Terry L. (Inventor)

    2005-01-01

    Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and were end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The resulting reactive end-capped liquid crystal oligomers exhibit a variety of improved and preferred physical properties. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,000 grams per mole. The end-capped liquid crystal oligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oligomers are stable for up to an hour in the melt phase. These properties make the end-capped liquid crystal oligomers highly processable by a variety of melt process shape forming and blending techniques including film extrusion, fiber spinning, reactive injection molding (RIM), resin transfer molding (RTM), resin film injection (RFI), powder molding, pultrusion, injection molding, blow molding, plasma spraying and thermo-forming. Once processed and shaped, the end-capped liquid crystal oligomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures. The resulting thermosets display many properties that are superior to their non-end-capped high molecular weight analogs.

  17. Liquid Crystalline Thermosets from Ester, Ester-Imide, and Ester-Amide Oligomers

    NASA Technical Reports Server (NTRS)

    Dingemans, Theodornus J. (Inventor); Weiser, Erik S. (Inventor); SaintClair, Terry L. (Inventor)

    2005-01-01

    Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and were end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The resulting reactive end-capped liquid crystal oligomers exhibit a variety of improved and preferred physical properties. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,OOO grams per mole. The end-capped liquid crystal oligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oligomers are stable for up to an hour in the melt phase. These properties make the end-capped liquid crystal oligomers highly processable by a variety of melt process shape forming and blending techniques including film extrusion, fiber spinning, reactive injection molding (RIM), resin transfer molding (RTM), resin film injection (RFI), powder molding, pultrusion, injection molding, blow molding, plasma spraying and thermo-forming. Once processed and shaped, the end- capped liquid crystal oligomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures. The resulting thermosets display many properties that are superior to their non-end-capped high molecular weight analogs.

  18. Spectroscopic studies on gallic acid and its azo derivatives and their iron(III) complexes.

    PubMed

    Masoud, Mamdouh S; Ali, Alaa E; Haggag, Sawsan S; Nasr, Nessma M

    2014-01-01

    Azo gallic derivatives and their iron(III) complexes were synthesized and characterized. The stereochemistry and the mode of bonding of the complexes were achieved based on elemental analysis, UV-Vis and IR. The thermal behaviors of the complexes were studied. The effect of pH on the electronic absorption spectra of gallic acid and its azo derivatives are discussed. Different spectroscopic methods (molar ratio, straight line method, continuous variation, slope ratio and successive method) are applied for determination of stoichiometry and pK values for the complex formation of gallic acid with iron(III) in aqueous media. Iron(III) complexes of gallic acid is formed with different ratio: 1:1, 1:2, 1:3 and 1:4 (M:L).

  19. Toxicity of aqueous C70-gallic acid suspension in Daphnia magna.

    PubMed

    Seda, Brandon C; Ke, Pu-Chun; Mount, Andrew S; Klaine, Stephen J

    2012-01-01

    The present study assessed the toxic effects of stable aqueous colloidal suspensions of gallic-acid-stabilized C(70) fullerene on Daphnia magna. The suspensions were stabilized through noncovalent surface modification with gallic acid. In addition to whole-organism responses, changes in antioxidative processes in D. magna were quantified. Acute toxicity was observed with 96LC50 for C(70) -gallic acid of 0.4 ± 0.1 mg/L C(70) . Daphnia magna fecundity was significantly reduced in 21-d bioassays at C(70) -gallic aqcid concentrations below quantifiable limits. Antioxidant enzyme activities of glutathione peroxidase and superoxide dismutase as well as lipid peroxidation suggested that exposed organisms experienced oxidative stress. Microscopic techniques used to determine cellular toxicity via apoptosis proved unsuccessful.

  20. Gallic Acid Promotes Wound Healing in Normal and Hyperglucidic Conditions.

    PubMed

    Yang, Dong Joo; Moh, Sang Hyun; Son, Dong Hwee; You, Seunghoon; Kinyua, Ann W; Ko, Chang Mann; Song, Miyoung; Yeo, Jinhee; Choi, Yun-Hee; Kim, Ki Woo

    2016-01-01

    Skin is the outermost layer of the human body that is constantly exposed to environmental stressors, such as UV radiation and toxic chemicals, and is susceptible to mechanical wounding and injury. The ability of the skin to repair injuries is paramount for survival and it is disrupted in a spectrum of disorders leading to skin pathologies. Diabetic patients often suffer from chronic, impaired wound healing, which facilitate bacterial infections and necessitate amputation. Here, we studied the effects of gallic acid (GA, 3,4,5-trihydroxybenzoic acid; a plant-derived polyphenolic compound) on would healing in normal and hyperglucidic conditions, to mimic diabetes, in human keratinocytes and fibroblasts. Our study reveals that GA is a potential antioxidant that directly upregulates the expression of antioxidant genes. In addition, GA accelerated cell migration of keratinocytes and fibroblasts in both normal and hyperglucidic conditions. Further, GA treatment activated factors known to be hallmarks of wound healing, such as focal adhesion kinases (FAK), c-Jun N-terminal kinases (JNK), and extracellular signal-regulated kinases (Erk), underpinning the beneficial role of GA in wound repair. Therefore, our results demonstrate that GA might be a viable wound healing agent and a potential intervention to treat wounds resulting from metabolic complications. PMID:27399667

  1. Complexation and molecular modeling studies of europium(III)-gallic acid-amino acid complexes.

    PubMed

    Taha, Mohamed; Khan, Imran; Coutinho, João A P

    2016-04-01

    With many metal-based drugs extensively used today in the treatment of cancer, attention has focused on the development of new coordination compounds with antitumor activity with europium(III) complexes recently introduced as novel anticancer drugs. The aim of this work is to design new Eu(III) complexes with gallic acid, an antioxida'nt phenolic compound. Gallic acid was chosen because it shows anticancer activity without harming health cells. As antioxidant, it helps to protect human cells against oxidative damage that implicated in DNA damage, cancer, and accelerated cell aging. In this work, the formation of binary and ternary complexes of Eu(III) with gallic acid, primary ligand, and amino acids alanine, leucine, isoleucine, and tryptophan was studied by glass electrode potentiometry in aqueous solution containing 0.1M NaNO3 at (298.2 ± 0.1) K. Their overall stability constants were evaluated and the concentration distributions of the complex species in solution were calculated. The protonation constants of gallic acid and amino acids were also determined at our experimental conditions and compared with those predicted by using conductor-like screening model for realistic solvation (COSMO-RS) model. The geometries of Eu(III)-gallic acid complexes were characterized by the density functional theory (DFT). The spectroscopic UV-visible and photoluminescence measurements are carried out to confirm the formation of Eu(III)-gallic acid complexes in aqueous solutions.

  2. Protective effects of gallic acid against spinal cord injury-induced oxidative stress.

    PubMed

    Yang, Yong Hong; Wang, Zao; Zheng, Jie; Wang, Ran

    2015-08-01

    The present study aimed to investigate the role of gallic acid in oxidative stress induced during spinal cord injury (SCI). In order to measure oxidative stress, the levels of lipid peroxide, protein carbonyl, reactive oxygen species and nitrates/nitrites were determined. In addition, the antioxidant status during SCI injury and the protective role of gallic acid were investigated by determining glutathione levels as well as the activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase. Adenosine triphophatase (ATPase) enzyme activities were determined to evaluate the role of gallic acid in SCI-induced deregulation of the activity of enzymes involved in ion homeostasis. The levels of inflammatory markers such as nuclear factor (NF)-κB and cycloxygenase (COX)-2 were determined by western blot analysis. Treatment with gallic acid was observed to significantly mitigate SCI-induced oxidative stress and the inflammatory response by reducing the oxidative stress, decreasing the expression of NF-κB and COX-2 as well as increasing the antioxidant status of cells. In addition, gallic acid modulated the activity of ATPase enzymes. Thus the present study indicated that gallic acid may have a role as a potent antioxidant and anti-inflammatory agent against SCI.

  3. Optimization of the condition for adsorption of gallic acid by Aspergillus oryzae mycelia using Box-Behnken design.

    PubMed

    Zhang, Zhicai; Pang, Qiaoxia; Li, Min; Zheng, Huihua; Chen, Hui; Chen, Keping

    2015-01-01

    Fresh biomass of Aspergillus oryzae (A. oryzae) CGMCC5992 can effectively remove gallic acid from aqueous solution. To improve the removal rate of gallic acid, this study first identified the important factors affecting the removal rate of gallic acid with univariate analysis, and then used four-factor and three-level Box-Behnken design (BBD) with the removal rate of gallic acid as response value, to obtain the optimum conditions for the removal of gallic acid as follows: 6.95 h treatment time, pH 3.70, 7.07 g/L mycelium volume, and 120.64 mg/L initial concentration of gallic acid. Under such optimized condition, the removal rate of gallic acid approached 99.21 %. HPLC-MS analysis proved that the gallic acid in aqueous solution was completely removed by A. oryzae, rather than being metabolized into its derivatives. Scanning electron microscopy (SEM) indicated that the biomass morphology and surface structure of A. oryzae changed after the adsorption of gallic acid. Thus, the present study has provided an optimal condition for A. oryzae removal of gallic acid in water.

  4. Antioxidative galloyl esters as enzyme inhibitors of p-hydroxybenzoate hydroxylase.

    PubMed

    Abe, I; Kashiwagi, K; Noguchi, H

    2000-10-20

    Gallic acid and its esters were evaluated as enzyme inhibitors of recombinant p-hydroxybenzoate hydroxylase (PHBH), a NADPH-dependent flavin monooxygenase from Pseudomonas aeruginosa. n-Dodecyl gallate (DG) (IC(50)=16 microM) and (-)-epigallocatechin-3-O-gallate (EGCG) (IC(50)=16 microM), a major component of green tea polyphenols, showed the most potent inhibition, while product-like gallic acid did not inhibit the enzyme significantly (IC(50)>250 microM). Inhibition kinetics revealed that both DG and EGCG inhibited PHBH in a non-competitive manner (K(I)=18.1 and 14.0 microM, respectively). The enzyme inhibition was caused by specific binding of the antioxidative gallate to the enzyme, and by scavenging reactive oxygen species required for the monooxygenase reaction. Molecular modeling predicted that EGCG binds to the enzyme in the proximity of the FAD binding site via formation of three hydrogen bonds.

  5. One-Pot Procedure for Recovery of Gallic Acid from Wastewater and Encapsulation within Protein Particles.

    PubMed

    Nourbakhsh, Himan; Madadlou, Ashkan; Emam-Djomeh, Zahra; Wang, Yi-Cheng; Gunasekaran, Sundaram; Mousavi, Mohammad E

    2016-02-24

    A whey protein isolate solution was heat-denatured and treated with the enzyme transglutaminase, which cross-linked ≈26% of the amino groups and increased the magnitude of the ζ-potential value. The protein solution was microemulsified, and then the resulting water-in-oil microemulsion was dispersed within a gallic acid-rich model wastewater. Gallic acid extraction by the outlined microemulsion liquid membrane (MLM) from the exterior aqueous phase (wastewater) and accumulation within the internal aqueous nanodroplets induced protein cold-set gelation and resulted in the formation of gallic acid-enveloping nanoparticles. Measurements with a strain-controlled rheometer indicated a progressive increase in the MLM viscosity during gallic acid recovery corresponding to particle formation. The mean hydrodynamic size of the nanoparticles made from the heat-denatured and preheated enzymatically cross-linked proteins was 137 and 122 nm, respectively. The enzymatic cross-linking of whey proteins led to a higher gallic acid recovery yield and increased the glass transition enthalpy and temperature. A similar impact on glass transition indices was observed by the gallic acid-induced nanoparticulation of proteins. Scanning electron microscopy showed the existence of numerous jammed/fused nanoparticles. It was suggested on the basis of the results of Fourier transform infrared spectroscopy that the in situ nanoparticulation of proteins shifted the C-N stretching and C-H bending peaks to higher wavenumbers. X-ray diffraction results proposed a decreased β-sheet content for proteins because of the acid-induced particulation. The nanoparticles made from the enzymatically cross-linked protein were more stable against the in vitro gastrointestinal digestion and retained almost 19% of the entrapped gallic acid after 300 min sequential gastric and intestinal digestions. PMID:26862880

  6. Determination of gallic acid with rhodanine by reverse flow injection analysis using simplex optimization.

    PubMed

    Phakthong, Wilaiwan; Liawruangrath, Boonsom; Liawruangrath, Saisunee

    2014-12-01

    A reversed flow injection (rFI) system was designed and constructed for gallic acid determination. Gallic acid was determined based on the formation of chromogen between gallic acid and rhodanine, resulting in a colored product with a λmax at 520 nm. The optimum conditions for determining gallic acid were also investigated. Optimizations of the experimental conditions were carried out based on the so-call univariate method. The conditions obtained were 0.6% (w/v) rhodanine, 70% (v/v) ethanol, 0.9 mol L(-1) NaOH, 2.0 mL min(-1) flow rate, 75 μL injection loop and 600 cm mixing tubing length, respectively. Comparative optimizations of the experimental conditions were also carried out by multivariate or simplex optimization method. The conditions obtained were 1.2% (w/v) rhodanine, 70% (v/v) ethanol, 1.2 mol L(-1) NaOH, flow rate 2.5 mL min(-1), 75 μL injection loop and 600 cm mixing tubing length, respectively. It was found that the optimum conditions obtained by the former optimization method were mostly similar to those obtained by the latter method. The linear relationship between peak height and the concentration of gallic acid was obtained over the range of 0.1-35.0 mg L(-1) with the detection limit 0.081 mg L(-1). The relative standard deviations were found to be in the ranges 0.46-1.96% for 1, 10, 30 mg L(-1) of gallic acid (n=11). The method has the advantages of simplicity extremely high selectivity and high precision. The proposed method was successfully applied to the determination of gallic acid in longan samples without interferent effects from other common phenolic compounds that might be present in the longan samples collected in northern Thailand.

  7. Gallic Acid Is an Antagonist of Semen Amyloid Fibrils That Enhance HIV-1 Infection.

    PubMed

    LoRicco, Josephine G; Xu, Changmingzi Sherry; Neidleman, Jason; Bergkvist, Magnus; Greene, Warner C; Roan, Nadia R; Makhatadze, George I

    2016-07-01

    Recent in vitro studies have demonstrated that amyloid fibrils found in semen from healthy and HIV-infected men, as well as semen itself, can markedly enhance HIV infection rates. Semen fibrils are made up of multiple naturally occurring peptide fragments derived from semen. The best characterized of these fibrils are SEVI (semen-derived enhancer of viral infection), made up of residues 248-286 of prostatic acidic phosphatase, and the SEM1 fibrils, made up of residues 86-107 of semenogelin 1. A small molecule screen for antagonists of semen fibrils identified four compounds that lowered semen-mediated enhancement of HIV-1 infectivity. One of the four, gallic acid, was previously reported to antagonize other amyloids and to exert anti-inflammatory effects. To better understand the mechanism by which gallic acid modifies the properties of semen amyloids, we performed biophysical measurements (atomic force microscopy, electron microscopy, confocal microscopy, thioflavin T and Congo Red fluorescence assays, zeta potential measurements) and quantitative assays on the effects of gallic acid on semen-mediated enhancement of HIV infection and inflammation. Our results demonstrate that gallic acid binds to both SEVI and SEM1 fibrils and modifies their surface electrostatics to render them less cationic. In addition, gallic acid decreased semen-mediated enhancement of HIV infection but did not decrease the inflammatory response induced by semen. Together, these observations identify gallic acid as a non-polyanionic compound that inhibits semen-mediated enhancement of HIV infection and suggest the potential utility of incorporating gallic acid into a multicomponent microbicide targeting both the HIV virus and host components that promote viral infection.

  8. One-Pot Procedure for Recovery of Gallic Acid from Wastewater and Encapsulation within Protein Particles.

    PubMed

    Nourbakhsh, Himan; Madadlou, Ashkan; Emam-Djomeh, Zahra; Wang, Yi-Cheng; Gunasekaran, Sundaram; Mousavi, Mohammad E

    2016-02-24

    A whey protein isolate solution was heat-denatured and treated with the enzyme transglutaminase, which cross-linked ≈26% of the amino groups and increased the magnitude of the ζ-potential value. The protein solution was microemulsified, and then the resulting water-in-oil microemulsion was dispersed within a gallic acid-rich model wastewater. Gallic acid extraction by the outlined microemulsion liquid membrane (MLM) from the exterior aqueous phase (wastewater) and accumulation within the internal aqueous nanodroplets induced protein cold-set gelation and resulted in the formation of gallic acid-enveloping nanoparticles. Measurements with a strain-controlled rheometer indicated a progressive increase in the MLM viscosity during gallic acid recovery corresponding to particle formation. The mean hydrodynamic size of the nanoparticles made from the heat-denatured and preheated enzymatically cross-linked proteins was 137 and 122 nm, respectively. The enzymatic cross-linking of whey proteins led to a higher gallic acid recovery yield and increased the glass transition enthalpy and temperature. A similar impact on glass transition indices was observed by the gallic acid-induced nanoparticulation of proteins. Scanning electron microscopy showed the existence of numerous jammed/fused nanoparticles. It was suggested on the basis of the results of Fourier transform infrared spectroscopy that the in situ nanoparticulation of proteins shifted the C-N stretching and C-H bending peaks to higher wavenumbers. X-ray diffraction results proposed a decreased β-sheet content for proteins because of the acid-induced particulation. The nanoparticles made from the enzymatically cross-linked protein were more stable against the in vitro gastrointestinal digestion and retained almost 19% of the entrapped gallic acid after 300 min sequential gastric and intestinal digestions.

  9. Gallic acid induced apoptotic events in HCT-15 colon cancer cells

    PubMed Central

    Subramanian, Aruna Priyadharshni; Jaganathan, Saravana Kumar; Mandal, Mahitosh; Supriyanto, Eko; Muhamad, Ida Idayu

    2016-01-01

    AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid (GA) against HCT-15 colon cancer cells. METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide (MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species (ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2’,7’-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1. RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase (0.98 ± 1.03 vs 58.01 ± 2.05) with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment. CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells. PMID:27099438

  10. Dispersion Characteristics of Multi-Walled Carbon Nanotubes with Gallic Acid.

    PubMed

    Jiang, Xiaosong; Shao, Zhenyi; Li, Jingrui; Liu, Wanxia; Zhu, Degui; Liu, Dan

    2015-12-01

    Dispersions of multi-walled carbon nanotubes (MW-CNTs) assisted by non-covalent surface modification and covalent surface modification were prepared using different concentration of gallic acid aqueous solution. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate the dispersion states and effect of MWNTs. FTIR results demonstrate that concentration of gallic acid has great effect on the surface modification of multi-walled carbon nanotubes. With the content of gallic acid increasing, modification effect were firstly increased and then decreased in that the optimal concentration is about 10 μg/ml as it is its solubility in water. SEM and TEM results also show that gallic acid not only can ensure the integrity of the MW-CNTs, but also can purify it. These results confirmed achievement of a good dispersion state and effect of MW-CNTs with gallic acid. The dispersion mechanism of non-covalent surface modification and covalent surface modification was analyzed.

  11. Molecular mechanics and dynamics studies on the interaction of gallic acid with collagen-like peptides

    NASA Astrophysics Data System (ADS)

    Madhan, B.; Thanikaivelan, P.; Subramanian, V.; Raghava Rao, J.; Unni Nair, Balachandran; Ramasami, T.

    2001-10-01

    Molecular modelling approaches have been used to understand the interaction of collagen-like peptides with gallic acid, which mimic vegetable tanning processes involved in protein stabilization. Several interaction sites have been identified and the binding energies of the complexes have been calculated. The calculated binding energies for various geometries are in the range 6-13 kcal/mol. It is found that some complexes exhibit hydrogen bonding, and electrostatic interaction plays a dominant role in the stabilization of the peptide by gallic acid. The π-OH type of interaction is also observed in the peptide stabilization. Molecular dynamics (MD) simulation for 600 ps revealed the possibility of hydrogen bonding between the collagen-like peptide and gallic acid.

  12. Effect of the structure of gallic acid and its derivatives on their interaction with plant ferritin.

    PubMed

    Wang, Qunqun; Zhou, Kai; Ning, Yong; Zhao, Guanghua

    2016-12-15

    Gallic acid and its derivatives co-exist with protein components in foodstuffs, but there is few report on their interaction with proteins. On the other hand, plant ferritin represents not only a novel class of iron supplement, but also a new nanocarrier for encapsulation of bioactive nutrients. However, plant ferritin is easy to be degraded by pepsin in the stomach, thereby limiting its application. Herein, we investigated the interaction of gallic acid and its derivatives with recombinant soybean seed H-2 ferritin (rH-2). We found that these phenolic acids interacted with rH-2 in a structure-dependent manner; namely, gallic acid (GA), methyl gallate (MEGA) and propyl gallate (PG) having three HO groups can bind to rH-2, while their analogues with two HO groups cannot. Consequently, such binding largely inhibited ferritin degradation by pepsin. These findings advance our understanding of the relationship between the structure and function of phenolic acids.

  13. Non-toxic agarose/gelatin-based microencapsulation system containing gallic acid for antifungal application.

    PubMed

    Lam, P-L; Gambari, R; Kok, S H-L; Lam, K-H; Tang, J C-O; Bian, Z-X; Lee, K K-H; Chui, C-H

    2015-02-01

    Aspergillus niger (A. niger) is a common species of Aspergillus molds. Cutaneous aspergillosis usually occurs in skin sites near intravenous injection and approximately 6% of cutaneous aspergillosis cases which do not involve burn or HIV-infected patients are caused by A. niger. Biomaterials and biopharmaceuticals produced from microparticle-based drug delivery systems have received much attention as microencapsulated drugs offer an improvement in therapeutic efficacy due to better human absorption. The frequently used crosslinker, glutaraldehyde, in gelatin-based microencapsulation systems is considered harmful to human beings. In order to tackle the potential risks, agarose has become an alternative polymer to be used with gelatin as wall matrix materials of microcapsules. In the present study, we report the eco-friendly use of an agarose/gelatin-based microencapsulation system to enhance the antifungal activity of gallic acid and reduce its potential cytotoxic effects towards human skin keratinocytes. We used optimal parameter combinations, such as an agarose/gelatin ratio of 1:1, a polymer/oil ratio of 1:60, a surfactant volume of 1% w/w and a stirring speed of 900 rpm. The minimum inhibitory concentration of microencapsulated gallic acid (62.5 µg/ml) was significantly improved when compared with that of the original drug (>750 µg/ml). The anti-A. niger activity of gallic acid -containing microcapsules was much stronger than that of the original drug. Following 48 h of treatment, skin cell survival was approximately 90% with agarose/gelatin microcapsules containing gallic acid, whereas cell viability was only 25-35% with free gallic acid. Our results demonstrate that agarose/gelatin-based microcapsules containing gallic acid may prove to be helpful in the treatment of A. niger-induced skin infections near intravenous injection sites.

  14. Antidepressant-like activity of gallic acid in mice subjected to unpredictable chronic mild stress.

    PubMed

    Chhillar, Ritu; Dhingra, Dinesh

    2013-08-01

    This study was designed to evaluate antidepressant-like activity of gallic acid in Swiss young male albino mice subjected to unpredictable chronic mild stress and to explore the possible underlying mechanisms for this activity. Gallic acid (5, 10, 20 mg/kg, i.p.) and fluoxetine (10 mg/kg, i.p.) per se were administered daily to unstressed mice and other groups of mice subjected to unpredictable mild stress, 30 min after the injection for 21 successive days. The antidepressant-like activity was evaluated using forced swim test (FST) and sucrose preference test. Stress significantly increased immobility period of mice in FST. Gallic acid (10 and 20 mg/kg, i.p.) and fluoxetine significantly decreased immobility period of unstressed and stressed mice in FST and prevented the stress-induced decrease in sucrose preference, indicating significant antidepressant-like activity. There was no significant effect on locomotor activity of the mice by the drugs. Gallic acid (10 and 20 mg/kg, i.p.) significantly decreased Monoamine oxidase-A (MAO-A) activity, malondialdehyde levels, and catalase activity in unstressed mice; and significantly prevented the stress-induced decrease in reduced glutathione and catalase activity; and also significantly prevented stress-induced increase in MAO-A activity, malondialdehyde levels, plasma nitrite, and corticosterone levels. Thus, gallic acid showed antidepressant-like activity in unstressed and stressed mice probably due to its antioxidant activity and through inhibition of MAO-A activity and decrease in plasma nitrite levels. In addition, gallic acid also showed antidepressant-like activity in stressed mice probably through decrease in plasma corticosterone levels.

  15. Antioxidant, cytotoxic activities, and structure-activity relationship of gallic acid-based indole derivatives.

    PubMed

    Khaledi, Hamid; Alhadi, Abeer A; Yehye, Wagee A; Ali, Hapipah Mohd; Abdulla, Mahmood A; Hassandarvish, Pouya

    2011-11-01

    A new series of gallic hydrazones containing an indole moiety was synthesized through the reaction of gallic hydrazide and different indole carboxaldehydes. Their antioxidant activities were determined on DPPH radical scavenging and inhibition of lipid peroxidation. The in-vitro cytotoxic activities of the compounds were evaluated against HCT-116 (human colon cancer cell line) and MCF-7 (estrogen-dependent human breast cancer cell line) by the MTT method. An attempt to correlate the biological results with their structural characteristics has been done. A limited positive structure activity relationship was found between cytotoxic and antioxidant activities.

  16. Gallic acid inhibits vascular calcification through the blockade of BMP2-Smad1/5/8 signaling pathway.

    PubMed

    Kee, Hae Jin; Cho, Soo-Na; Kim, Gwi Ran; Choi, Sin Young; Ryu, Yuhee; Kim, In Kyeom; Hong, Young Joon; Park, Hyung Wook; Ahn, Youngkeun; Cho, Jeong Gwan; Park, Jong Chun; Jeong, Myung Ho

    2014-11-01

    Vascular calcification is associated with increased risk of morbidity and mortality in patients with cardiovascular diseases, chronic kidney diseases, and diabetes. Gallic acid, a natural compound found in gallnut and green tea, is known to be antifungal, antioxidant, and anticancer. Here we investigated the effect of gallic acid on vascular smooth muscle cell (VSMC) calcification and the underlying mechanism. Gallic acid inhibited inorganic phosphate-induced osteoblast differentiation markers as well as calcification phenotypes (as determined by calcium deposition, Alizarin Red, and Von Kossa staining). Knockdown of BMP2 or Noggin blocked phosphate-induced calcification. Gallic acid suppressed phosphorylation of Smad1/5/8 protein induced by inorganic phosphate. Taken together, we suggest that gallic acid acts as a novel therapeutic agent of vascular calcification by mediating BMP2-Smad1/5/8 signaling pathway.

  17. The Influence of Prefermentative Addition of Gallic Acid on the Phenolic Composition and Chromatic Characteristics of Cabernet Sauvignon Wines.

    PubMed

    Liu, Yue; Zhang, Bo; He, Fei; Duan, Chang-Qing; Shi, Ying

    2016-07-01

    In this study, the prefermentative addition of gallic acid in Cabernet Sauvignon red winemaking was performed. The influence of gallic acid addition on wine phenolic composition, the ratio of copigmentation, and the color parameters were monitored throughout the winemaking process. The results showed that the prefermentative addition of gallic acid enhanced the extraction of total anthocyanins and the copigmentation effect, producing wines with more darkness, redness, yellowness, and saturation. Moreover, the addition of gallic acid contributed to the concentration of total phenolic acids. However, it had a negative effect on the concentrations of flavonols and flavan-3-ols in the final wines. Thus, the prefermentative addition of gallic acid at appropriate levels might be a promising enological technology to obtain wines with high color quality and aging potential.

  18. Tert-butyl-2(4,5-dihydrogen-4,4,5,5-tetramethyl-3-O-1H-imidazole-3-cationic-1-oxyl-2-pyrrolidine-1-carboxylic ester displays novel cytotoxicity through reactive oxygen species-mediated oxidative damage in MCF-7 and MDA-MB-231 cells.

    PubMed

    Zhang, Yanjun; Guo, Juan; Zeng, Lihua; Zhang, Jie; Hui, Yanping; Liu, Junye; Qing, Xiangyang; Sun, Xiaoli; Guo, Guozhen

    2011-07-15

    The cytotoxicity of a new nitroxyl nitroxide radical, tert-butyl-2 (4,5-dihydrogen-4,4,5,5-tetramethyl-3-O-1H-imidazole-3-cationic-1-oxyl-2-pyrrolidine-1-carboxylic ester (L-NNP) was examined in MCF-7 and MDA-MB-231 cells. L-NNP treatment resulted in a significant growth inhibition in MCF-7 and MDA-MB-231 cells. Compared with control, 10, 30, and 50μg/ml L-NNP treatments for 48h induced significant cell and nuclei swelling, and organelle distension. The marked cell death was seen in a concentration- and time-dependant manner in L-NNP treated groups. The L-NNP treated group displayed a concentration-dependant increase in DNA double strand damage compared to the control and the 1Gy γ-rays exposure groups. These results suggest that L-NNP could result in more lethal genotoxicity than 1Gy γ-radiation. Based on mitochondrial alteration (membrane potential loss and SDH activity descend), DNA damage, an increase in MDA production, and GSH-PX inactivation, we predicate that L-NNP induces lipid oxidation and oxidative damage in MCF-7 and MDA-MB-231 cells. Since L-NNP initiated a significant increase in reactive oxygen species, which could largely be inhibited by NAC pretreatment, the overall data strongly suggest that the mechanism of cytotoxicity of L-NNP was its ability to act as a strong free radical, and significantly increase intracellular reactive oxygen species production. This led to intracellular oxidative damage, and antioxidant enzyme inactivation, resulting in cell death. We hypothesize that the greater cytotoxicity of L-NNP in MDA-MB-231 cells than in MCF-7 cells might be due to more ROS production in MDA-MB-231 cells, leading to more oxidative damage.

  19. Influence of different free radicals on scavenging potency of gallic acid.

    PubMed

    Đorović, Jelena; Marković, Jasmina M Dimitrić; Stepanić, Višnja; Begović, Nebojša; Amić, Dragan; Marković, Zoran

    2014-07-01

    The M05-2X/6-311++G(d,p) and B3LYP-D2/6-311++G(d,p) models are used to evaluate scavenging potency of gallic acid. The hydrogen atom transfer (HAT), sequential proton loss electron transfer (SPLET), and single electron transfer followed by proton transfer (SET-PT) mechanisms of gallic acid with some radicals ((•)OO(-), (•)OH, and CH3OO(•)) were investigated using the corresponding thermodynamic quantities: bond dissociation enthalpy (BDE), ionization potential (IP), and proton affinity (PA). Namely, the ΔHBDE, ΔHIP, and ΔHPA values of the corresponding reactions in some solvents (water, DMSO, pentylethanoate, and benzene) are investigated using an implicit solvation model (SMD). An approach based on the reactions enthalpies related to the examined mechanisms is applied. This approach shows that a thermodynamically favored mechanism depends on the polarity of reaction media and properties of free radical reactive species. The most acidic 4-OH group of gallic acid is the active site for radical inactivation. The results of this investigation indicate that the SPLET mechanism can be a favored reaction pathway for all three radicals in all solvents, except for (•)OH in the aqueous solution. In water, gallic acid can inactivate (•)OH by the HAT mechanism.

  20. Gallic Acid, the Active Ingredient of Terminalia bellirica, Enhances Adipocyte Differentiation and Adiponectin Secretion.

    PubMed

    Makihara, Hiroko; Koike, Yuka; Ohta, Masatomi; Horiguchi-Babamoto, Emi; Tsubata, Masahito; Kinoshita, Kaoru; Akase, Tomoko; Goshima, Yoshio; Aburada, Masaki; Shimada, Tsutomu

    2016-01-01

    Visceral obesity induces the onset of metabolic disorders such as insulin resistance and diabetes mellitus. Adipose tissue is considered as a potential pharmacological target for treating metabolic disorders. The fruit of Terminalia bellirica is extensively used in Ayurvedic medicine to treat patients with diseases such as diabetes mellitus. We previously investigated the effects of a hot water extract of T. bellirica fruit (TB) on obesity and insulin resistance in spontaneously obese type 2 diabetic mice. To determine the active ingredients of TB and their molecular mechanisms, we focused on adipocyte differentiation using mouse 3T3-L1 cells, which are widely used to study adipocyte physiology. We show here that TB enhanced the differentiation of 3T3-L1 cells to mature adipocytes and that one of the active main components was identified as gallic acid. Gallic acid (10-30 µM) enhanced the expression and secretion of adiponectin via adipocyte differentiation and also that of fatty acid binding protein-4, which is the target of peroxisome proliferator-activated receptor gamma (PPARγ), although it does not alter the expression of the upstream genes PPARγ and CCAAT enhancer binding protein alpha. In the PPARγ ligand assay, the binding of gallic acid to PPARγ was undetectable. These findings indicate that gallic acid mediates the therapeutic effects of TB on metabolic disorders by regulating adipocyte differentiation. Therefore, TB shows promise as a candidate for preventing and treating patients with metabolic syndrome. PMID:27374289

  1. Gallic Acid, the Active Ingredient of Terminalia bellirica, Enhances Adipocyte Differentiation and Adiponectin Secretion.

    PubMed

    Makihara, Hiroko; Koike, Yuka; Ohta, Masatomi; Horiguchi-Babamoto, Emi; Tsubata, Masahito; Kinoshita, Kaoru; Akase, Tomoko; Goshima, Yoshio; Aburada, Masaki; Shimada, Tsutomu

    2016-01-01

    Visceral obesity induces the onset of metabolic disorders such as insulin resistance and diabetes mellitus. Adipose tissue is considered as a potential pharmacological target for treating metabolic disorders. The fruit of Terminalia bellirica is extensively used in Ayurvedic medicine to treat patients with diseases such as diabetes mellitus. We previously investigated the effects of a hot water extract of T. bellirica fruit (TB) on obesity and insulin resistance in spontaneously obese type 2 diabetic mice. To determine the active ingredients of TB and their molecular mechanisms, we focused on adipocyte differentiation using mouse 3T3-L1 cells, which are widely used to study adipocyte physiology. We show here that TB enhanced the differentiation of 3T3-L1 cells to mature adipocytes and that one of the active main components was identified as gallic acid. Gallic acid (10-30 µM) enhanced the expression and secretion of adiponectin via adipocyte differentiation and also that of fatty acid binding protein-4, which is the target of peroxisome proliferator-activated receptor gamma (PPARγ), although it does not alter the expression of the upstream genes PPARγ and CCAAT enhancer binding protein alpha. In the PPARγ ligand assay, the binding of gallic acid to PPARγ was undetectable. These findings indicate that gallic acid mediates the therapeutic effects of TB on metabolic disorders by regulating adipocyte differentiation. Therefore, TB shows promise as a candidate for preventing and treating patients with metabolic syndrome.

  2. Comparison and combination effects on antioxidant power of curcumin with gallic acid, ascorbic acid, and xanthone.

    PubMed

    Naksuriya, Ornchuma; Okonogi, Siriporn

    2015-04-01

    Curcumin has been extensively reported as a potential natural antioxidant. However, there was no data on activity comparison as well as the biological interactions of curcumin with other natural antioxidants. The aim of the present study was to investigate the antioxidant power of curcumin in comparison with three important natural antioxidants; gallic acid, ascorbic acid, and xanthone on free radical scavenging action and their combination effects on this activity. The results indicated that the activities of these compounds were dose-dependent. The 50% effective concentration (EC50) of curcumin was found to be 11 μg/mL. Curcumin showed significantly higher antioxidant activity than ascorbic acid and xanthone but less than gallic acid. Interestingly, curcumin revealed synergistic antioxidant effect when combined with gallic acid whereas the antagonistic effect occurred in curcumin combination with ascorbic acid or xanthone. These results suggest that curcumin-gallic acid combination is the potential antioxidant mixture to be used in place of the individual substance whereas using of curcumin in combination with ascorbic acid or xanthone should be avoid.

  3. Preparation of Fe3O4 magnetic nanoparticles coated with gallic acid for drug delivery

    PubMed Central

    Dorniani, Dena; Hussein, Mohd Zobir Bin; Kura, Aminu Umar; Fakurazi, Sharida; Shaari, Abdul Halim; Ahmad, Zalinah

    2012-01-01

    Background and methods Magnetic iron oxide nanoparticles were prepared using a sonochemical method under atmospheric conditions at a Fe2+ to Fe3+ molar ratio of 1:2. The iron oxide nanoparticles were subsequently coated with chitosan and gallic acid to produce a core-shell structure. Results X-ray diffraction demonstrated that the magnetic nanoparticles were pure Fe3O4 with a cubic inverse spinel structure. Transmission electron microscopy showed that the Fe3O4 nanoparticles were of spherical shape with a mean diameter of 11 nm, compared with 13 nm for the iron oxide-chitosan-gallic acid (FCG) nanocarriers. Conclusion The magnetic nanocarrier enhanced the thermal stability of the drug, gallic acid. Release of the active drug from the FCG nanocarrier was found to occur in a controlled manner. The gallic acid and FCG nanoparticles were not toxic in a normal human fibroblast (3T3) line, and anticancer activity was higher in HT29 than MCF7 cell lines. PMID:23166439

  4. Kenaf methyl esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Additional or alternative feedstocks are one of the major areas of interest regarding biodiesel. In this paper, for the first time, the fuel properties of kenaf (Hibiscus cannabinus L.) seed oil methyl esters are comprehensively reported. This biodiesel is also relatively unique by containing small ...

  5. meso-Ester Corroles.

    PubMed

    Canard, Gabriel; Gao, Di; D'Aléo, Anthony; Giorgi, Michel; Dang, Florian-Xuan; Balaban, Teodor Silviu

    2015-05-18

    The introduction of ester groups on the 5- and 15-meso positions of corroles stabilizes them against oxidation and induces a redshift of their absorption and emission spectra. These effects are studied through the photophysical and electrochemical characterization of up to 16 different 5,15-diester corroles, in which the third meso position is free or occupied by an aryl group, a long alkyl chain, or an ester moiety. Single-crystal X-ray structure analysis of five 5,15-diestercorroles and DFT and time-dependent DFT calculations show that the strong electron-withdrawing character of the 5,15 ester substituents is reinforced by their π overlap with the macrocyclic aromatic system. The crystal packing of corroles 2, 4, 6, 9, and 15 features short distances between chromophores that are stacked into columns thanks to the low steric hindrance of meso-ester groups. This close packing is partially due to intermolecular interactions that involve inner hydrogen and nitrogen atoms, and thereby, stabilize a single, identical corrole tautomeric form. PMID:25786789

  6. Antimicrobial activity of gallic acid against thermophilic Campylobacter is strain specific and associated with a loss of calcium ions.

    PubMed

    Sarjit, Amreeta; Wang, Yi; Dykes, Gary A

    2015-04-01

    Gallic acid has been suggested as a potential antimicrobial for the control of Campylobacter but its effectiveness is poorly studied. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of gallic acid against Campylobacter jejuni (n = 8) and Campylobacter coli (n = 4) strains was determined. Gallic acid inhibited the growth of five C. jejuni strains and three C. coli strains (MIC: 15.63-250 μg mL(-1)). Gallic acid was only bactericidal to two C. coli strains (MBC: 125 and 62.5 μg mL(-1)). The mechanism of the bactericidal effect against these two strains (and selected non-susceptible controls) was investigated by determining decimal reduction times and by monitoring the loss of cellular content and calcium ions, and changes in cell morphology. Gallic acid did not result in a loss of cellular content or morphological changes in the susceptible strains as compared to the controls. Gallic acid resulted in a loss of calcium ions (0.58-1.53 μg mL(-1) and 0.54-1.17 μg mL(-1), respectively, over a 180 min period) from the susceptible strains but not the controls. Gallic acid is unlikely to be an effective antimicrobial against Campylobacter in a practical sense unless further interventions to ensure an effective bactericidal mode of action against all strains are developed.

  7. Gallic acid protects RINm5F beta-cells from glucolipotoxicity by its antiapoptotic and insulin-secretagogue actions.

    PubMed

    Sameermahmood, Zaheer; Raji, Lenin; Saravanan, Thangavel; Vaidya, Ashok; Mohan, Viswanathan; Balasubramanyam, Muthuswamy

    2010-01-01

    Gallic acid is claimed to possess antioxidant, antiinflammatory and cytoprotective effects. Since pancreatic islets from Type 2 diabetic patients have functional defects, it was hypothesized that glucolipotoxicity might induce apoptosis in beta-cells and gallic acid could offer protection. To test this, RINm5F beta-cells were exposed to high glucose (25 microM) or palmitate (500 microM) or a combination of both for 24 h in the presence and absence of gallic acid. Cells subjected to glucolipotoxicity in the absence and presence of gallic acid were assessed for DNA damage by comet assay. Apoptosis was inferred by caspase-3 protein expression and caspase-3 activity and changes in Bcl-2 mRNA. RT-PCR was used to analyse PDX-1, insulin and UCP-2 mRNA expression in RINm5F beta-cells and insulin levels were quantified from the cell culture supernatant. NFkappaB signal was studied by EMSA, immunofluorescence and Western blot analysis. While RINm5F beta-cells subjected to glucolipotoxicity exhibited increased DNA damage, apoptotic markers and NFkappaB signals, all these apoptotic perturbations were resisted by gallic acid. Gallic acid dose-dependently increased insulin secretion in RINm5F beta-cells and upregulated mRNA of PDX-1 and insulin. It is suggested that the insulin-secretagogue and transcriptional regulatory action of gallic acid is a newly identified mechanism in our study.

  8. Structure-Activity Relationships of Antimicrobial Gallic Acid Derivatives from Pomegranate and Acacia Fruit Extracts against Potato Bacterial Wilt Pathogen.

    PubMed

    Farag, Mohamed A; Al-Mahdy, Dalia A; Salah El Dine, Riham; Fahmy, Sherifa; Yassin, Aymen; Porzel, Andrea; Brandt, Wolfgang

    2015-06-01

    Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc-zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity-guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5-dihydroxy-4-methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5-9 mg/ml), with 3,5-dihydroxy-4-methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure-activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids.

  9. Structure-Activity Relationships of Antimicrobial Gallic Acid Derivatives from Pomegranate and Acacia Fruit Extracts against Potato Bacterial Wilt Pathogen.

    PubMed

    Farag, Mohamed A; Al-Mahdy, Dalia A; Salah El Dine, Riham; Fahmy, Sherifa; Yassin, Aymen; Porzel, Andrea; Brandt, Wolfgang

    2015-06-01

    Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc-zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity-guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5-dihydroxy-4-methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5-9 mg/ml), with 3,5-dihydroxy-4-methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure-activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids. PMID:26080741

  10. Potent and selective inhibition of squalene epoxidase by synthetic galloyl esters.

    PubMed

    Abe, I; Seki, T; Noguchi, H

    2000-04-01

    n-Alkyl esters (ethyl, octyl, dodecyl, and cetyl) of gallic acid were evaluated as enzyme inhibitors of recombinant rat squalene epoxidase (SE), a rate-limiting enzyme of cholesterol biogenesis. Dodecyl (6) (IC(50) = 0.061 microM) showed the most potent inhibition, which was far more potent than those of previously reported naturally occurring gallocatechins. Octyl gallate (5) (IC(50) = 0.83 microM) and cetyl gallate (7) (IC(50) = 0.59 microM) also showed good inhibition, while gallic acid (IC(50) = 73 microM) itself was not so active. In addition, chemically synthesized galloyl ester of cholesterol (9) (IC(50) = 3.9 microM), farnesol derivative (10) (IC(50) = 0.57 microM), and dodecyl galloyl amide (8) (IC(50) = 3.0 microM) were also potent inhibitors of SE. Inhibition kinetics revealed that dodecyl gallate inhibited SE in competitive (K(I) = 0.033 microM) and no-time-dependent manner. The potent inhibition of the flavin monooxygenase would be caused by specific binding to the enzyme, and by scavenging reactive oxygen species required for the epoxidation reaction.

  11. The ESTER project

    NASA Astrophysics Data System (ADS)

    Rieutord, M.; Dintrans, B.; Lignières, F.; Corbard, T.; Pichon, B.

    2005-12-01

    The ESTER project aims at building a stellar evolution code in two dimensions of space for the study of effects of rotation. The numerical scheme is based on spectral methods with a spherical harmonic decomposition in the horizontal direction and a Chebyshev polynomial expansion in the vertical direction. Coordinates adapted to the centrifugally distorted shape are mapped to spherical coordinates. First tests on rotating polytropes are presented.

  12. SERS spectrum of gallic acid obtained from a modified silver colloid.

    PubMed

    Garrido, C; Diaz-Fleming, G; Campos-Vallette, M M

    2016-06-15

    Two different crystals of the gallic acid were microscopically separated from a p.a. commercial product. The Raman spectra analysis allowed distinguishing monomeric and dimeric structures. The vibrational wave numbers were computed using DFT quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in the Raman spectrum. The dimer, characterized as ellagic acid, involves the carboxyl and hydroxyl moieties. The Raman spectrum in water solution of each species is dominated by the monomeric form. A low negatively charged Ag colloid allowed obtain to the best of our knowledge, the first surface enhanced Raman scattering (SERS) spectrum of the gallic acid. The possible electrophilic attacking sites of the title molecule are identified using MEP surface plot study and the orientation of the analyte on the metal surface is proposed tilted to the surface.

  13. Synthesis and spectroscopic characterization of gallic acid and some of its azo complexes

    NASA Astrophysics Data System (ADS)

    Masoud, Mamdouh S.; Hagagg, Sawsan S.; Ali, Alaa E.; Nasr, Nessma M.

    2012-04-01

    A series of gallic acid and azo gallic acid complexes were prepared and characterized by elemental analysis, IR, electronic spectra and magnetic susceptibility. The complexes were of different geometries: Octahedral, Tetrahedral and Square Planar. ESR was studied for copper complexes. All of the prepared complexes were of isotropic nature. The thermal analyses of the complexes were studied by DTA and DSC techniques. The thermodynamic parameters and the thermal transitions, such as glass transitions, crystallization and melting temperatures for some ligands and their complexes were evaluated and discussed. The entropy change values, ΔS#, showed that the transition states are more ordered than the reacting complexes. The biological activities of some ligands and their complexes are tested against Gram positive and Gram negative bacteria. The results showed that some complexes have a well considerable activity against different organisms.

  14. SERS spectrum of gallic acid obtained from a modified silver colloid

    NASA Astrophysics Data System (ADS)

    Garrido, C.; Diaz-Fleming, G.; Campos-Vallette, M. M.

    2016-06-01

    Two different crystals of the gallic acid were microscopically separated from a p.a. commercial product. The Raman spectra analysis allowed distinguishing monomeric and dimeric structures. The vibrational wave numbers were computed using DFT quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in the Raman spectrum. The dimer, characterized as ellagic acid, involves the carboxyl and hydroxyl moieties. The Raman spectrum in water solution of each species is dominated by the monomeric form. A low negatively charged Ag colloid allowed obtain to the best of our knowledge, the first surface enhanced Raman scattering (SERS) spectrum of the gallic acid. The possible electrophilic attacking sites of the title molecule are identified using MEP surface plot study and the orientation of the analyte on the metal surface is proposed tilted to the surface.

  15. SERS spectrum of gallic acid obtained from a modified silver colloid.

    PubMed

    Garrido, C; Diaz-Fleming, G; Campos-Vallette, M M

    2016-06-15

    Two different crystals of the gallic acid were microscopically separated from a p.a. commercial product. The Raman spectra analysis allowed distinguishing monomeric and dimeric structures. The vibrational wave numbers were computed using DFT quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in the Raman spectrum. The dimer, characterized as ellagic acid, involves the carboxyl and hydroxyl moieties. The Raman spectrum in water solution of each species is dominated by the monomeric form. A low negatively charged Ag colloid allowed obtain to the best of our knowledge, the first surface enhanced Raman scattering (SERS) spectrum of the gallic acid. The possible electrophilic attacking sites of the title molecule are identified using MEP surface plot study and the orientation of the analyte on the metal surface is proposed tilted to the surface. PMID:27037765

  16. Gallic Acid as a Complexing Agent for Copper Chemical Mechanical Polishing Slurries at Neutral pH

    NASA Astrophysics Data System (ADS)

    Kim, Yung Jun; Kang, Min Cheol; Kwon, Oh Joong; Kim, Jae Jeong

    2011-05-01

    Gallic acid was investigated as a new complexing agent for copper (Cu) chemical mechanical polishing slurries at neutral pH. Addition of 0.03 M gallic acid and 1.12 M H2O2 at pH 7 resulted in a Cu removal rate of 560.73±17.49 nm/min, and the ratio of the Cu removal rate to the Cu dissolution rate was 14.8. Addition of gallic acid improved the slurry performance compared to glycine addition. X-ray photoelectron spectroscopy analysis and contact angle measurements showed that addition of gallic acid enhanced the Cu polishing behavior by suppressing the formation of surface Cu oxide.

  17. Acute toxicity and sublethal effects of gallic and pelargonic acids on the zebrafish Danio rerio.

    PubMed

    Techer, Didier; Milla, Sylvain; Fontaine, Pascal; Viot, Sandrine; Thomas, Marielle

    2015-04-01

    Gallic and pelargonic acids are naturally found in a variety of plants and food products. Despite their extensive use in man-made applications, little is known regarding their potential risks to aquatic vertebrates. The aim of this work was to assess the acute toxicity of these polyphenolic and fatty acid compounds to the zebrafish. In order to get insights into sublethal effects, the enzyme activity of usual biomarkers related to oxidative stress and biotransformation were also assessed in fish. These latter included total superoxide dismutase, catalase as well as total glutathione peroxidase for antioxidant defence mechanisms and glutathione S-transferase for biotransformation related enzyme. Gallic acid was practically non-toxic (96-h lethal concentration (LC50) > 100 mg/L) whereas pelargonic acid was slightly toxic (96-h LC50 of 81.2 mg/L). Moreover, biomarker analyses indicated enhanced superoxide dismutase activity in fish exposed to 20, 40 and 100 mg/L of gallic acid compared to control. A dose-dependent induction of glutathione peroxidase and glutathione S-transferase was reported following gallic acid exposure at the tested concentrations of 10, 20 and 40 mg/L, with the exception of 100 mg/L of substance where basal activity levels were reported. In the case of pelargonic acid, there was no change in antioxidant enzyme activity while an inhibition of glutathione S-transferase was observed from organisms exposed to 45, 58 and 76 mg/L of test solution. The results concerning sublethal effects on biological parameters of zebrafish highlighted thereby the need for further investigations following chronic exposure to both organic acids.

  18. SBA-15 Mesoporous Silica Modified with Gallic Acid and Evaluation of Its Cytotoxic Activity

    PubMed Central

    Lewandowski, Dawid

    2015-01-01

    Gallic acid has been covalently conjugated to SBA-15 mesoporous silica surface through different linkers. Cytotoxic activity of the hybrid organic-inorganic systems against HeLa and KB cell lines has been analyzed. Up to 67% of HeLa or KB tumor cells growth inhibition has been achieved at low silica concentration used (10 μg mL-1). PMID:26151908

  19. Reproductive toxicity of phthalate esters.

    PubMed

    Martino-Andrade, Anderson Joel; Chahoud, Ibrahim

    2010-01-01

    Phthalate esters are ubiquitous environmental contaminants that in general display low-toxicity. Overall, the reproductive effects of these compounds are well characterized in adult's animals, with gonadal injury observed after high dose exposure. However, results of recent transgeneration studies indicate that the reproductive system of developing animals is particularly vulnerable to certain phthalates. The phenotypic alterations observed in male offspring rats exposed during the perinatal period have remarkable similarities with common human reproductive disorders, including cryptorchidism, hypospadias and low-sperm counts. Recent results also indicate that high phthalate doses can adversely affect adult and developing female rats. However, the main question involving phthalates is whether the current level of human exposure is sufficient to adversely affect male and/or female reproductive health. Here, we review the reproductive toxicity data of phthalates in adult and developing animals as well as possible modes of action. In addition, we briefly discuss the relevance of animal studies to humans in light of recent epidemiological data and experimental research with low (human relevant) doses. Finally, we point out some critical issues that should be addressed in order to clarify the implications of phthalates for human reproduction. PMID:19760678

  20. One-pot nanoparticulation of potentially bioactive peptides and gallic acid encapsulation.

    PubMed

    Nourbakhsh, Himan; Madadlou, Ashkan; Emam-Djomeh, Zahra; Wang, Yi-Cheng; Gunasekaran, Sundaram

    2016-11-01

    Whey protein isolate was hydrolyzed to an in vitro antioxidative hydrolysate, followed by transglutaminase-induced cross-linking and microemulsification in an oil phase. The obtained microemulsion was then dispersed in a gallic acid-rich model wastewater which caused gallic acid transportation into internal nanodroplets. Whey peptides were consequently gelled, yielding nanoparticles. Electrophoresis showed that β-lactoglobulin and low molecular weight peptides were cross-linked by transglutaminase. Protein hydrolysis and subsequent enzymatic cross-linking increased the ζ-potential value. Microscopic investigation indicated that most particles were non-spherical. Non-cross-linked and cross-linked peptides underwent a form of heat-triggered self-assembly in the dry state, while nanoparticles did not show such behavior. Peptide crystallites size was increased by cross-linking and acid-induced particle formation. The latter also caused a reduction in intensity of C-H stretching and C-N bending peaks in infra-red spectrum. Gallic acid release from particles to simulated gastrointestinal fluids was through diffusion from swollen particles, and reached almost 70% release. PMID:27211653

  1. One-pot nanoparticulation of potentially bioactive peptides and gallic acid encapsulation.

    PubMed

    Nourbakhsh, Himan; Madadlou, Ashkan; Emam-Djomeh, Zahra; Wang, Yi-Cheng; Gunasekaran, Sundaram

    2016-11-01

    Whey protein isolate was hydrolyzed to an in vitro antioxidative hydrolysate, followed by transglutaminase-induced cross-linking and microemulsification in an oil phase. The obtained microemulsion was then dispersed in a gallic acid-rich model wastewater which caused gallic acid transportation into internal nanodroplets. Whey peptides were consequently gelled, yielding nanoparticles. Electrophoresis showed that β-lactoglobulin and low molecular weight peptides were cross-linked by transglutaminase. Protein hydrolysis and subsequent enzymatic cross-linking increased the ζ-potential value. Microscopic investigation indicated that most particles were non-spherical. Non-cross-linked and cross-linked peptides underwent a form of heat-triggered self-assembly in the dry state, while nanoparticles did not show such behavior. Peptide crystallites size was increased by cross-linking and acid-induced particle formation. The latter also caused a reduction in intensity of C-H stretching and C-N bending peaks in infra-red spectrum. Gallic acid release from particles to simulated gastrointestinal fluids was through diffusion from swollen particles, and reached almost 70% release.

  2. Time-dependent inhibition of CYP3A4 by gallic acid in human liver microsomes and recombinant systems.

    PubMed

    Pu, Qiang-Hong; Shi, Liang; Yu, Chao

    2015-03-01

    1.Gallic acid is a main polyphenol in various fruits and plants. Inhibitory characteristics of gallic acid on CYP3A4 were still unclear. The objective of this work is hence to investigate inhibitory characteristics of gallic acid on CYP3A4 using testosterone as the probe substrate in human liver microsomes (HLMs) and recombinant CYP3A4 (rCYP3A4) systems. 2.Gallic acid caused concentration-dependent loss of CYP3A4 activity with IC50 values of 615.2 μM and 669.5 μM in HLM and rCYP3A4 systems, respectively. IC50-shift experiments showed that pre-incubation with gallic acid in the absence of NADPH contributed to 12- or 14-fold reduction of IC50 in HLM and rCYP3A4 systems, respectively, supporting a time-dependent inhibition. In HLM, time-dependent inactivation variables KI and Kinact were 485.8 μM and 0.05 min(-1), respectively. 3.Compared with the presence of NADPH, pre-incubation of gallic acid in the absence of NADPH markedly increased its inhibitory effects in HLM and rCYP3A4 systems. Those results indicate that CYP3A4 inactivation by gallic acid was independent on NADPH and was mainly mediated its oxidative products. 4.In conclusion, we showed that gallic acid weakly and time-dependently inactivated CYP3A4 via its oxidative products.

  3. Method of making alkyl esters

    DOEpatents

    Elliott, Brian

    2010-09-14

    Methods of making alkyl esters are described herein. The methods are capable of using raw, unprocessed, low-cost feedstocks and waste grease. Generally, the method involves converting a glyceride source to a fatty acid composition and esterifying the fatty acid composition to make alkyl esters. In an embodiment, a method of making alkyl esters comprises providing a glyceride source. The method further comprises converting the glyceride source to a fatty acid composition comprising free fatty acids and less than about 1% glyceride by mass. Moreover, the method comprises esterifying the fatty acid composition in the presence of a solid acid catalyst at a temperature ranging firm about 70.degree. C. to about 120.degree. C. to produce alkyl esters, such that at least 85% of the free fatty acids are converted to alkyl esters. The method also incorporates the use of packed bed reactors for glyceride conversion and/or fatty acid esterification to make alkyl esters.

  4. Hepatoprotective effect of trimethylgallic acid esters against carbon tetrachloride-induced liver injury in rats.

    PubMed

    Sachdeva, Mamta; Chadha, Renu; Kumar, Anil; Karan, Maninder; Singh, Tejvir; Dhingra, Sameer

    2015-12-01

    Gallic acid and its derivatives are potential therapeutic agents for treating various oxidative stress mediated disorders. In the present study, we investigated the hepatoprotective effects of newly synthesized conjugated trimethylgallic acid (TMGA) esters against carbon tetrachloride (CCl4)-induced hepatotoxicity in rats. Animals were pre-treated with TMGA esters at their respective doses for 7 days against CCl4-induced hepatotoxicity. The histopathological changes were evaluated to find out degenerative fatty changes including vacuole formation, inflammation and tissue necrosis. Various biomarkers of oxidative stress (lipid peroxidation, glutathione levels, and endogenous antioxidant enzyme activities), liver enzymes (AST and ALT), triacylglycerol and cholesterol were evaluated. Pre-treatment with TMGA esters (MRG, MGG, MSG, and MUG at the dose of 28.71, 30.03, 31.35, 33.62 mg/kg/day), respectively reversed the CCl4-induced liver injury scores (reduced vacuole formation, inflammation and necrosis), biochemical parameters of plasma (increased AST, ALT, TG, and cholesterol), antioxidant enzymes (increased lipid peroxidation and nitrite levels; decreased glutathione levels, superoxide dismutase and catalase activities) in liver tissues and inflammatory surge (serum TNF-α) significantly. The study revealed that TMGA esters exerted hepatoprotective effects in CCl4-induced rats, specifically by modulating oxidative-nitrosative stress and inflammation.

  5. Two shikimate dehydrogenases, VvSDH3 and VvSDH4, are involved in gallic acid biosynthesis in grapevine.

    PubMed

    Bontpart, Thibaut; Marlin, Thérèse; Vialet, Sandrine; Guiraud, Jean-Luc; Pinasseau, Lucie; Meudec, Emmanuelle; Sommerer, Nicolas; Cheynier, Véronique; Terrier, Nancy

    2016-05-01

    In plants, the shikimate pathway provides aromatic amino acids that are used to generate numerous secondary metabolites, including phenolic compounds. In this pathway, shikimate dehydrogenases (SDH) 'classically' catalyse the reversible dehydrogenation of 3-dehydroshikimate to shikimate. The capacity of SDH to produce gallic acid from shikimate pathway metabolites has not been studied in depth. In grapevine berries, gallic acid mainly accumulates as galloylated flavan-3-ols. The four grapevine SDH proteins have been produced in Escherichia coli In vitro, VvSDH1 exhibited the highest 'classical' SDH activity. Two genes, VvSDH3 and VvSDH4, mainly expressed in immature berry tissues in which galloylated flavan-3-ols are accumulated, encoded enzymes with lower 'classical' activity but were able to produce gallic acid in vitro The over-expression of VvSDH3 in hairy-roots increased the content of aromatic amino acids and hydroxycinnamates, but had little or no effect on molecules more distant from the shikimate pathway (stilbenoids and flavan-3-ols). In parallel, the contents of gallic acid, β-glucogallin, and galloylated flavan-3-ols were increased, attesting to the influence of this gene on gallic acid metabolism. Phylogenetic analysis from dicotyledon SDHs opens the way for the examination of genes from other plants which accumulate gallic acid-based metabolites. PMID:27241494

  6. Effect of Gallic acid on mechanical and water barrier properties of zein-oleic acid composite films.

    PubMed

    Masamba, Kingsley; Li, Yue; Hategekimana, Joseph; Liu, Fei; Ma, Jianguo; Zhong, Fang

    2016-05-01

    In this study, the effect of gallic acid on mechanical and water barrier properties of zein-oleic acid 0-4 % composite films was investigated. Molecular weight distribution analysis was carried out to confirm gallic acid induced cross linking through change in molecular weight in fraction containing zein proteins. Results revealed that gallic acid treatment increased tensile strength from 17.9 MPa to 26.0 MPa, decreased water vapour permeability from 0.60 (g mm m(-2) h(-1) kPa(-1)) to 0.41 (g mm m(-2) h(-1) kPa(-1)), increased solubility from 6.3 % to 10.2 % and marginally increased elongation at break from 3.7 % to 4.2 % in zein films only. However, gallic acid treatment in zein-oleic composite films did not significantly influence mechanical and water barrier properties and in most instances irrespective of oleic acid concentration, the properties were negatively affected. Results from scanning electron microscopy showed that both gallic acid treated and untreated zein films and composite films containing 3 % oleic acid had a compact and homogeneous structure while those containing 4 % oleic acid had inhomogeneous structure. The findings have demonstrated that gallic acid treatment can significantly improve mechanical and water barrier properties especially in zein films only as opposed to when used in composite films using zein and oleic acid. PMID:27407188

  7. Gallic Acid Decreases Inflammatory Cytokine Secretion Through Histone Acetyltransferase/Histone Deacetylase Regulation in High Glucose-Induced Human Monocytes.

    PubMed

    Lee, Wooje; Lee, Sang Yeol; Son, Young-Jin; Yun, Jung-Mi

    2015-07-01

    Hyperglycemia contributes to diabetes and several diabetes-related complications. Gallic acid is a polyhydroxy phenolic compound found in various natural products. In this study, we investigated the effects and mechanism of gallic acid on proinflammatory cytokine secretion in high glucose-induced human monocytes (THP-1 cells). THP-1 cells were cultured under normoglycemic or hyperglycemic conditions, in the absence or presence of gallic acid. Hyperglycemic conditions significantly induced histone acetylation, nuclear factor-κB (NF-κB) activation, and proinflammatory cytokine release from THP-1 cells, whereas gallic acid suppressed NF-κB activity and cytokine release. It also significantly reduced CREB-binding protein/p300 (CBP/p300, a NF-κB coactivator) gene expression, acetylation levels, and CBP/p300 histone acetyltransferase (HAT) activity. In addition, histone deacetylase 2 (HDAC2) expression was significantly induced. These results suggest that gallic acid inhibits hyperglycemic-induced cytokine production in monocytes through epigenetic changes involving NF-κB. Therefore, gallic acid may have potential for the treatment and prevention of diabetes and its complications.

  8. Effect of Gallic acid on mechanical and water barrier properties of zein-oleic acid composite films.

    PubMed

    Masamba, Kingsley; Li, Yue; Hategekimana, Joseph; Liu, Fei; Ma, Jianguo; Zhong, Fang

    2016-05-01

    In this study, the effect of gallic acid on mechanical and water barrier properties of zein-oleic acid 0-4 % composite films was investigated. Molecular weight distribution analysis was carried out to confirm gallic acid induced cross linking through change in molecular weight in fraction containing zein proteins. Results revealed that gallic acid treatment increased tensile strength from 17.9 MPa to 26.0 MPa, decreased water vapour permeability from 0.60 (g mm m(-2) h(-1) kPa(-1)) to 0.41 (g mm m(-2) h(-1) kPa(-1)), increased solubility from 6.3 % to 10.2 % and marginally increased elongation at break from 3.7 % to 4.2 % in zein films only. However, gallic acid treatment in zein-oleic composite films did not significantly influence mechanical and water barrier properties and in most instances irrespective of oleic acid concentration, the properties were negatively affected. Results from scanning electron microscopy showed that both gallic acid treated and untreated zein films and composite films containing 3 % oleic acid had a compact and homogeneous structure while those containing 4 % oleic acid had inhomogeneous structure. The findings have demonstrated that gallic acid treatment can significantly improve mechanical and water barrier properties especially in zein films only as opposed to when used in composite films using zein and oleic acid.

  9. Two shikimate dehydrogenases, VvSDH3 and VvSDH4, are involved in gallic acid biosynthesis in grapevine.

    PubMed

    Bontpart, Thibaut; Marlin, Thérèse; Vialet, Sandrine; Guiraud, Jean-Luc; Pinasseau, Lucie; Meudec, Emmanuelle; Sommerer, Nicolas; Cheynier, Véronique; Terrier, Nancy

    2016-05-01

    In plants, the shikimate pathway provides aromatic amino acids that are used to generate numerous secondary metabolites, including phenolic compounds. In this pathway, shikimate dehydrogenases (SDH) 'classically' catalyse the reversible dehydrogenation of 3-dehydroshikimate to shikimate. The capacity of SDH to produce gallic acid from shikimate pathway metabolites has not been studied in depth. In grapevine berries, gallic acid mainly accumulates as galloylated flavan-3-ols. The four grapevine SDH proteins have been produced in Escherichia coli In vitro, VvSDH1 exhibited the highest 'classical' SDH activity. Two genes, VvSDH3 and VvSDH4, mainly expressed in immature berry tissues in which galloylated flavan-3-ols are accumulated, encoded enzymes with lower 'classical' activity but were able to produce gallic acid in vitro The over-expression of VvSDH3 in hairy-roots increased the content of aromatic amino acids and hydroxycinnamates, but had little or no effect on molecules more distant from the shikimate pathway (stilbenoids and flavan-3-ols). In parallel, the contents of gallic acid, β-glucogallin, and galloylated flavan-3-ols were increased, attesting to the influence of this gene on gallic acid metabolism. Phylogenetic analysis from dicotyledon SDHs opens the way for the examination of genes from other plants which accumulate gallic acid-based metabolites.

  10. Antiulcerogenic Effect of Gallic Acid in Rats and its Effect on Oxidant and Antioxidant Parameters in Stomach Tissue

    PubMed Central

    Sen, S.; Asokkumar, K.; Umamaheswari, M.; Sivashanmugam, A. T.; Subhadradevi, V.

    2013-01-01

    In the present study, we investigate the antiulcerogenic effect of gallic acid against aspirin plus pyrolus ligation-induced gastric ulcer in rats. Rats were treated with gallic acid (100 and 200 mg/kg) and famotidine (20 mg/kg) for 1 week, followed by induction of gastric ulcer using the aspirin plus pyrolus ligation model. At the end of 4 h after ligation, the rats were sacrificed and ulcer index, gastric juice volume, pH and other biochemical parameter of gastric juice were evaluated. Stomachs of rats were evaluated biochemically to determine oxidant and antioxidant parameters. Pretreatment with gallic acid significantly decreased ulcer index, gastric juice volume, free and total acidity, total protein, DNA content and increased pH and carbohydrates concentration. Gallic acid at a dose of 100 and 200 mg/kg exerted 69.7 and 78.9% ulcer inhibition, respectively. The levels of superoxide dismutase, catalase, reduced glutathione, glutathione reductase, glutathione peroxidise, glucose-6-phosphate dehydrogenase were increased while reduction in myeloperoxidase and lipid peroxidation were observed in the stomach tissues of the drug treated rats. The histopathological studies further confirmed the antiulcer activity of gallic acid. We conclude that the gallic acid possesses antiulcer effect and that these occur by a mechanism that involves attenuation of offensive factors, improvement of mucosal defensive with activation of antioxidant parameters and inhibition of some toxic oxidant parameters. PMID:24019562

  11. Anticancer property of gallic acid in A549, a human lung adenocarcinoma cell line, and possible mechanisms

    PubMed Central

    Maurya, Dharmendra K.; Nandakumar, Nivedita; Devasagayam, Thomas Paul Asir

    2011-01-01

    Gallic acid is widely distributed in plants, fruits and foods with a range of biological activities. In the present study the possible mechanisms of gallic acid anticancer properties were explored in A549, a human lung adenocarcinoma cell line. Our study shows that it inhibited the A549 cell growth and decreased cell viability monitored at 24 h. It also inhibited cell proliferation in dose- and time-dependent manner as measured by 3-[4,5-methylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide assay at 24 and 48 h. Morphological examination of the cells after gallic acid treatment showed the typical feature of cell death such as cell shrinkage and rounding up of the cells. Clonogenic assay indicated that gallic acid treatments inhibited the colony formation. DNA fragmentation assay indicated the disappearance of the genomic DNA in dose-dependent manner. To find out possible mechanisms, mitochondrial potential and intracellular reactive oxygen species were measured. It was observed that gallic acid treatment decreased mitochondrial membrane potential and increased intracellular reactive oxygen species. Further caspases activity was measured and it was found that gallic acid activated the caspase-3 but not caspase-8 indicating the involvement of intrinsic pathway of cell apoptosis. PMID:21297918

  12. Two shikimate dehydrogenases, VvSDH3 and VvSDH4, are involved in gallic acid biosynthesis in grapevine

    PubMed Central

    Bontpart, Thibaut; Marlin, Thérèse; Vialet, Sandrine; Guiraud, Jean-Luc; Pinasseau, Lucie; Meudec, Emmanuelle; Sommerer, Nicolas; Cheynier, Véronique; Terrier, Nancy

    2016-01-01

    In plants, the shikimate pathway provides aromatic amino acids that are used to generate numerous secondary metabolites, including phenolic compounds. In this pathway, shikimate dehydrogenases (SDH) ‘classically’ catalyse the reversible dehydrogenation of 3-dehydroshikimate to shikimate. The capacity of SDH to produce gallic acid from shikimate pathway metabolites has not been studied in depth. In grapevine berries, gallic acid mainly accumulates as galloylated flavan-3-ols. The four grapevine SDH proteins have been produced in Escherichia coli. In vitro, VvSDH1 exhibited the highest ‘classical’ SDH activity. Two genes, VvSDH3 and VvSDH4, mainly expressed in immature berry tissues in which galloylated flavan-3-ols are accumulated, encoded enzymes with lower ‘classical’ activity but were able to produce gallic acid in vitro. The over-expression of VvSDH3 in hairy-roots increased the content of aromatic amino acids and hydroxycinnamates, but had little or no effect on molecules more distant from the shikimate pathway (stilbenoids and flavan-3-ols). In parallel, the contents of gallic acid, β-glucogallin, and galloylated flavan-3-ols were increased, attesting to the influence of this gene on gallic acid metabolism. Phylogenetic analysis from dicotyledon SDHs opens the way for the examination of genes from other plants which accumulate gallic acid-based metabolites. PMID:27241494

  13. Antiproliferative and uncoupling effects of delocalized, lipophilic, cationic gallic acid derivatives on cancer cell lines. Validation in vivo in singenic mice.

    PubMed

    Jara, José A; Castro-Castillo, Vicente; Saavedra-Olavarría, Jorge; Peredo, Liliana; Pavanni, Mario; Jaña, Fabián; Letelier, María Eugenia; Parra, Eduardo; Becker, María Inés; Morello, Antonio; Kemmerling, Ulrike; Maya, Juan Diego; Ferreira, Jorge

    2014-03-27

    Tumor cells principally exhibit increased mitochondrial transmembrane potential (ΔΨ(m)) and altered metabolic pathways. The therapeutic targeting and delivery of anticancer drugs to the mitochondria might improve treatment efficacy. Gallic acid exhibits a variety of biological activities, and its ester derivatives can induce mitochondrial dysfunction. Four alkyl gallate triphenylphosphonium lipophilic cations were synthesized, each differing in the size of the linker chain at the cationic moiety. These derivatives were selectively cytotoxic toward tumor cells. The better compound (TPP(+)C10) contained 10 carbon atoms within the linker chain and exhibited an IC50 value of approximately 0.4-1.6 μM for tumor cells and a selectivity index of approximately 17-fold for tumor compared with normal cells. Consequently, its antiproliferative effect was also assessed in vivo. The oxygen consumption rate and NAD(P)H oxidation levels increased in the tumor cell lines (uncoupling effect), resulting in a ΔΨ(m) decrease and a consequent decrease in intracellular ATP levels. Moreover, TPP(+)C10 significantly inhibited the growth of TA3/Ha tumors in mice. According to these results, the antineoplastic activity and safety of TPP(+)C10 warrant further comprehensive evaluation.

  14. Synthesis of pyromellitic acid esters

    NASA Technical Reports Server (NTRS)

    Fedorova, V. A.; Donchak, V. A.; Martynyuk-Lototskaya, A. N.

    1985-01-01

    The ester acids necessary for studyng the thermochemical properties of pyromellitic acid (PMK)-based peroxides were investigated. Obtaining a tetramethyl ester of a PMK was described. The mechanism of an esterification reaction is discussed, as is the complete esterification of PMK with primary alcohol.

  15. Lipoate ester multifunctional lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven lipoate esters were synthesized by esterification of lipoic acid with different structures of alcohols in the presence of a solid acid catalyst and without solvent. The esters were obtained in good yield, characterized using 1H NMR and GPC; and their physical properties investigated. Four of t...

  16. Synthesis and anti-human immunodeficiency virus type 1 integrase activity of hydroxybenzoic and hydroxycinnamic acid flavon-3-yl esters.

    PubMed

    Desideri, N; Sestili, I; Stein, M L; Tramontano, E; Corrias, S; La Colla, P

    1998-11-01

    A series of new hydroxybenzoic and hydroxycinnamic acid flavon-3-yl esters were synthesized in order to obtain compounds targeting the human immunodeficiency virus (HIV) type 1 integrase (IN). The esters were tested for anti-IN and anti-reverse transcriptase (RT) activity in enzyme assays and for anti-HIV-1, anti-proliferative and anti-topoisomerase activity in cell-based assays. In enzyme assays, the two gallic acid flavon-3-yl esters showed a notable IN inhibition (IC50 values were 8.3 and 9.1 microM, respectively), while the two caffeic acid flavon-3-yl esters exhibited a modest activity (IC50 75 and 60 microM, respectively). Replacement of hydroxyl groups resulted in loss of potency. Caffeic acid 3',4'-dichloroflavon-3-yl ester also inhibited the RT activity whereas it was not active on human topoisomerases. It therefore represents an interesting example of a compound specifically targeting more than one step of the virus replication cycle.

  17. Propyl gallate synthesis using acidophilic tannase and simultaneous production of tannase and gallic acid by marine Aspergillus awamori BTMFW032.

    PubMed

    Beena, P S; Basheer, Soorej M; Bhat, Sarita G; Bahkali, Ali H; Chandrasekaran, M

    2011-07-01

    Marine Aspergillus awamori BTMFW032, recently reported by us, produce acidophilic tannase as extracellular enzyme. Here, we report the application of this enzyme for synthesis of propyl gallate by direct transesterification of tannic acid and in tea cream solubilisation besides the simultaneous production of gallic acid along with tannase under submerged fermentation by this fungus. This acidophilic tannase enabled synthesis of propyl gallate by direct transesterification of tannic acid using propanol as organic reaction media under low water conditions. The identity of the product was confirmed with thin layer chromatography and Fourier transform infrared spectroscopy. It was noted that 699 U/ml of enzyme could give 60% solubilisation of tea cream within 1 h. Enzyme production medium was optimized adopting Box-Behnken design for simultaneous synthesis of tannase and gallic acid. Process variables including tannic acid, sodium chloride, ferrous sulphate, dipotassium hydrogen phosphate, incubation period and agitation were recognized as the critical factors that influenced tannase and gallic acid production. The model obtained predicted 4,824.61 U/ml of tannase and 136.206 μg/ml gallic acid after 48 h of incubation, whereas optimized medium supported 5,085 U/ml tannase and 372.6 μg/ml of gallic acid production after 36 and 84 h of incubation, respectively, with a 15-fold increase in both enzyme and gallic acid production. Results indicated scope for utilization of this acidophilic tannase for transesterification of tannic acid into propyl gallate, tea cream solubilisation and simultaneous production of gallic acid along with tannase.

  18. The effect of gallic acid on cytotoxicity, Ca(2+) homeostasis and ROS production in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes.

    PubMed

    Hsu, Shu-Shong; Chou, Chiang-Ting; Liao, Wei-Chuan; Shieh, Pochuen; Kuo, Daih-Huang; Kuo, Chun-Chi; Jan, Chung-Ren; Liang, Wei-Zhe

    2016-05-25

    Gallic acid, a polyhydroxylphenolic compound, is widely distributed in various plants, fruits and foods. It has been shown that gallic acid passes into blood brain barrier and reaches the brain tissue of middle cerebral artery occlusion rats. However, the effect of gallic acid on Ca(2+) signaling in glia cells is unknown. This study explored whether gallic acid affected Ca(2+) homeostasis and induced Ca(2+)-associated cytotoxicity in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes. Gallic acid (20-40 μM) concentration-dependently induced cytotoxicity and intracellular Ca(2+) level ([Ca(2+)]i) increases in DBTRG-05MG cells but not in CTX TNA2 cells. In DBTRG-05MG cells, the Ca(2+) response was decreased by half by removal of extracellular Ca(2+). In Ca(2+)-containing medium, gallic acid-induced Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (2-APB, econazole and SKF96365). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin abolished gallic acid-induced [Ca(2+)]i increases. Conversely, incubation with gallic acid also abolished thapsigargin-induced [Ca(2+)]i increases. Inhibition of phospholipase C with U73122 abolished gallic acid-induced [Ca(2+)]i increases. Gallic acid significantly caused cytotoxicity in DBTRG-05MG cells, which was partially prevented by prechelating cytosolic Ca(2+) with BAPTA-AM. Moreover, gallic acid activated mitochondrial apoptotic pathways that involved ROS production. Together, in DBTRG-05MG cells but not in CTX TNA2 cells, gallic acid induced [Ca(2+)]i increases by causing Ca(2+) entry via 2-APB, econazole and SKF96365-sensitive store-operated Ca(2+) entry, and phospholipase C-dependent release from the endoplasmic reticulum. This Ca(2+) signal subsequently evoked mitochondrial pathways of apoptosis that involved ROS production.

  19. The effect of gallic acid on cytotoxicity, Ca(2+) homeostasis and ROS production in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes.

    PubMed

    Hsu, Shu-Shong; Chou, Chiang-Ting; Liao, Wei-Chuan; Shieh, Pochuen; Kuo, Daih-Huang; Kuo, Chun-Chi; Jan, Chung-Ren; Liang, Wei-Zhe

    2016-05-25

    Gallic acid, a polyhydroxylphenolic compound, is widely distributed in various plants, fruits and foods. It has been shown that gallic acid passes into blood brain barrier and reaches the brain tissue of middle cerebral artery occlusion rats. However, the effect of gallic acid on Ca(2+) signaling in glia cells is unknown. This study explored whether gallic acid affected Ca(2+) homeostasis and induced Ca(2+)-associated cytotoxicity in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes. Gallic acid (20-40 μM) concentration-dependently induced cytotoxicity and intracellular Ca(2+) level ([Ca(2+)]i) increases in DBTRG-05MG cells but not in CTX TNA2 cells. In DBTRG-05MG cells, the Ca(2+) response was decreased by half by removal of extracellular Ca(2+). In Ca(2+)-containing medium, gallic acid-induced Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (2-APB, econazole and SKF96365). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin abolished gallic acid-induced [Ca(2+)]i increases. Conversely, incubation with gallic acid also abolished thapsigargin-induced [Ca(2+)]i increases. Inhibition of phospholipase C with U73122 abolished gallic acid-induced [Ca(2+)]i increases. Gallic acid significantly caused cytotoxicity in DBTRG-05MG cells, which was partially prevented by prechelating cytosolic Ca(2+) with BAPTA-AM. Moreover, gallic acid activated mitochondrial apoptotic pathways that involved ROS production. Together, in DBTRG-05MG cells but not in CTX TNA2 cells, gallic acid induced [Ca(2+)]i increases by causing Ca(2+) entry via 2-APB, econazole and SKF96365-sensitive store-operated Ca(2+) entry, and phospholipase C-dependent release from the endoplasmic reticulum. This Ca(2+) signal subsequently evoked mitochondrial pathways of apoptosis that involved ROS production. PMID:27060209

  20. An ellagitannin, n-butyl gallate, two aryltetralin lignans, and an unprecedented diterpene ester from Pelargonium reniforme.

    PubMed

    Latté, Klaus Peter; Kaloga, Maki; Schäfer, Andreas; Kolodziej, Herbert

    2008-02-01

    The structural diversity of the metabolic pool of Pelargonium reniforme was extended by the characterization of the 1C4-glucose based ellagitannin pelargoniin E, gallic acid n-butyl ester, (-)-4,4',9'-trihydroxy-3',5'-dimethoxy-2,7'-cyclolignan 9-O-beta-glucopyranoside and reniformin, a diterpene ester comprised of a diterpene acid with an uncommon -(CH2)(2)- bridging element linked to 2-(4-hydroxyphenyl)ethansulfonic acid. These metabolites were associated with the known (alpha,beta)-3,4-di-O-galloyl-glucopyranoside, 4,6-dihydroxy-2beta-glucopyranosyloxyacetophenone, 1-O-galloylglycerol, 6'-O-galloylsalidroside and (+)-isolariciresinol-9'-O-beta-glucopyranoside. All structures were established on the basis of spectroscopic methods.

  1. Kinetic study of the complexation of gallic acid with Fe(II)

    NASA Astrophysics Data System (ADS)

    Lu, Li-li; Li, Ying-hua; Lu, Xiu-yang

    2009-10-01

    Kinetic study on the complexation of gallic acid with ferrous sulfate was performed using UV-Vis absorption spectroscopy. Under the experimental conditions, the stoichiometric composition of the formed complex is 1:1. The complexation reaction was found to be a second-order one. The influences of temperature, ionic strength and solvents on the complexation reaction were investigated. According to the Arrhenius equation, the apparent activation energy of the complexation reaction was evaluated to be 71.64 kJ × mol -1. A three-step reaction mechanism was proposed, which can well explain the kinetic results obtained.

  2. Effects of chitosan, gallic acid, and algicide on the physiological and biochemical properties of Microcystis flos-aquae.

    PubMed

    Guo, Peiyong; Liu, Yang; Liu, Cong

    2015-09-01

    The effects of chitosan, gallic acid, and algicide chitosan-gallate on the activities of antioxidant enzymes, malonaldehyde (MDA) content, and photosynthetic activity of Microcystis flos-aquae were investigated to explore the physiological and biochemical mechanisms of algicides. Results demonstrated that chitosan did not significantly affect catalase (CAT) and superoxide dismutase (SOD) activities, MDA content, and photosynthetic activity in this alga. At 30 mg L(-1), gallic acid, CAT, and SOD activities and MDA of M. flos-aquae cells showed maximums of 2.872 × 10(-10) mg·cell(-1) min(-1), 0.787 × 10(-8) U·cell(-1), and 0.626 × 10(-8) nmol·cell(-1), respectively. Photosynthetic organs in algal cells were severely damaged under the stress of high gallic acid concentrations, inducing blockage of photosynthetic electron transport and resulting in the inability to restore normal photosynthetic activity. CAT and SOD activities and MDA content with lower algicide concentration were significantly higher than the control group (p < 0.05) and, in higher algicide groups, significantly lower than the control (p < 0.05). Algicide releasing gallic acid in groups treated with 60, 90, and 130 mg/L algicide was strong enough to cause severe damage to photosynthetic organs in these algal cells. The algicide suppression time was longer than that of directly added gallic acid.

  3. Statistical optimization of bioprocess parameters for enhanced gallic acid production from coffee pulp tannins by Penicillium verrucosum.

    PubMed

    Bhoite, Roopali N; Navya, P N; Murthy, Pushpa S

    2013-01-01

    Gallic acid (3,4,5-trihydroxybenzoic acid) was produced by microbial biotransformation of coffee pulp tannins by Penicillium verrucosum. Gallic acid production was optimized using response surface methodology (RSM) based on central composite rotatable design. Process parameters such as pH, moisture, and fermentation period were considered for optimization. Among the various fungi isolated from coffee by-products, Penicillium verrucosum produced 35.23 µg/g of gallic acid on coffee pulp as sole carbon source in solid-state fermentation. The optimum values of the parameters obtained from the RSM were pH 3.32, moisture 58.40%, and fermentation period of 96 hr. Gallic acid production with an increase of 4.6-fold was achieved upon optimization of the process parameters. The results optimized could be translated to 1-kg tray fermentation. High-performance liquid chromatography (HPLC) analysis and spectral studies such as mass spectroscopy (MS) and (1)H-nuclear magnetic resonance (NMR) confirmed that the bioactive compound isolated was gallic acid. Thus, coffee pulp, which is available in enormous quantity, could be used for the production of value-added products that can find avenues in food, pharmaceutical, and chemical industries.

  4. Display formats manual

    NASA Technical Reports Server (NTRS)

    Runnels, R. L.

    1973-01-01

    The standards and procedures for the generation of operational display formats to be used in the Mission Control Center (MCC) display control system are presented. The required effort, forms, and fundamentals for the design, specifications, and production of display formats are identified. The principles of display design and system constraints controlling the creation of optimum operational displays for mission control are explained. The basic two types of MCC display systems for presenting information are described.

  5. Effect of gallic acid and catechin on Lactobacillus hilgardii 5w growth and metabolism of organic compounds.

    PubMed

    Alberto, M R; Farías, M E; Manca De Nadra, M C

    2001-09-01

    The effects of different concentrations of (+)-catechin and gallic acid on the growth and metabolism of Lactobacillus hilgardii in different media were evaluated. These phenolic compounds at concentrations normally present in wine not only stimulated the growth rate but also resulted in greater cell densities during the stationary phase of growth in both media. During the first hours of growth both phenolic compounds activated the rate of glucose and fructose utilization and only catechin increased the malic acid consumption rate. Gallic acid and catechin were consumed from the beginning of L. hilgardii growth. All cited effects were increased when the cells were precultivated in the presence of phenolic compounds, especially in the FT80 medium. As stimulating agents of L. hilgardii 5w growth, gallic acid and catechin could increase the risk of spoilage lactic acid bacteria in wine.

  6. [Optimization of extraction technology for salidroside, tyrosol, crenulatin and gallic acid in Rhodiolae Crenulatae Radix et Rhizoma with orthogonal test].

    PubMed

    Luo, Xin; Wang, Xue-jing; Zhao, Yi-wu; Huang, Wen-zhe; Wang, Zhen-zhong; Xiao, Wei

    2015-09-01

    The extracting technology of salidroside, tyrosol, crenulatin and gallic acid from Rhodiolae Crenulatae Radix et Rhizoma was optimized. With extraction rate of salidroside, tyrosol, crenulatin and gallic acid as indexes, orthogonal test was used to evaluate effect of 4 factors on extracting technology, including concentration of solvent, the dosage of solvent, duration of extraction, and frequency of extraction. The results showed that, the best extracting technology was to extract in 70% alcohol with 8 times the weight of herbal medicine for 2 times, with 3 hours once. High extraction rate of salidroside, tyrosol, crenulatin and gallic acid were obtained with the present technology. The extracting technology was stable and feasible with high extraction rate of four compounds from Rhodiolae Crenulatae Radix et Rhizoma, it was suitable for industrial production.

  7. Singlet oxygen-sensitized delayed emissions from hydrogen peroxide/gallic acid/potassium ferricyanide systems containing organic solvents

    NASA Astrophysics Data System (ADS)

    Ishii, Hiroshi; Tsukino, Kazuo; Sekine, Masahiko; Nakata, Munetaka

    2009-06-01

    Fourier-transform chemiluminescence spectra of H 2O 2/gallic acid/K 3[Fe(CN) 6] systems containing organic solvents were measured. Emission bands with peaks around 530 and 700 nm were observed in systems containing solvents with a carbonyl group such as N, N-dimethylformamide, and those with a hydroxyl group such as methanol, respectively. The relative band intensities depended strongly on the concentration of these organic solvents. The emission species are attributed to gallic acid-ferricyanide complexes excited by energy transfer from singlet oxygen dimol, ( 1O 2) 2. The effects of organic solvents are interpreted in terms of intermolecular interactions of gallic acid-ferricyanide complexes, water molecules and organic solvents.

  8. Gold Nanoparticles Enhance the Anticancer Activity of Gallic Acid against Cholangiocarcinoma Cell Lines.

    PubMed

    Rattanata, Narintorn; Daduang, Sakda; Wongwattanakul, Molin; Leelayuwat, Chanvit; Limpaiboon, Temduang; Lekphrom, Ratsami; Sandee, Alisa; Boonsiri, Patcharee; Chio-Srichan, Sirinart; Daduang, Jureerut

    2015-01-01

    Gold nanoparticles (GNPs) were conjugated with gallic acid (GA) at various concentrations between 30 and 150 μM and characterized using transmission electron microscopy (TEM) and UV-Vis spectroscopy (UV-VIS). The anticancer activities of the gallic acid-stabilized gold nanoparticles against well-differentiated (M213) and moderately differentiated (M214) adenocarcinomas were then determined using a neutral red assay. The GA mechanism of action was evaluated using Fourier transform infrared (FTIR) microspectroscopy. Distinctive features of the FTIR spectra between the control and GA-treated cells were confirmed by principal component analysis (PCA). The surface plasmon resonance spectra of the GNPs had a maximum absorption at 520 nm, whereas GNPs-GA shifted the maximum absorption values. In an in vitro study, the complexed GNPs-GA had an increased ability to inhibit the proliferation of cancer cells that was statistically significant (P<0.0001) in both M213 and M214 cells compared to GA alone, indicating that the anticancer activity of GA can be improved by conjugation with GNPs. Moreover, PCA revealed that exposure of the tested cells to GA resulted in significant changes in their cell membrane lipids and fatty acids, which may enhance the efficacy of this anticancer activity regarding apoptosis pathways.

  9. Luminescent behavior of cadmium sulfide quantum dots for gallic acid estimation

    NASA Astrophysics Data System (ADS)

    Singh, Suman; Garg, Sourav; Chahal, Jitender; Raheja, Khushboo; Singh, Deepak; Singla, M. L.

    2013-03-01

    Thioglycolic acid capped cadmium sulfide (CdS/T) quantum dots have been synthesized using wet chemistry and their optical behavior has been investigated using UV-visible absorption and fluorescence spectroscopy. The role of the capping agent, sulfide source concentration, pH and temperature has been studied and discussed. Studies showed that alkaline pH leads to a decrease in the size of quantum dots and reflux temperature above 70 °C resulted in red-shift of emission spectra which is due to narrowing of the bandgap. Further, to reduce the toxicity and photochemical instability of quantum dots, the quantum dots have been functionalized with polyethylene glycol (PEG), which resulted in a 20% enhancement of the fluorescence intensity. The application potential of CdS/T-PEG quantum dots was further studied using gallic acid as a model compound. The sensing is based on fluorescence quenching of quantum dots in the presence of gallic acid, and this study showed linearity in the range from 1.3 × 10-8 to 46.5 × 10-8 mM, with a detection limit of 3.6 × 10-8 mM.

  10. Antistaphylococcal and biofilm inhibitory activities of gallic, caffeic, and chlorogenic acids.

    PubMed

    Luís, Ângelo; Silva, Filomena; Sousa, Sónia; Duarte, Ana Paula; Domingues, Fernanda

    2014-01-01

    Staphylococcus aureus is a Gram-positive pathogen which is able to form biofilms, exhibiting a more pronounced resistance to antibiotics and disinfectants. The hurdles posed in eradicating biofilms have driven the search for new compounds able to fight these structures. Phenolic compounds constitute one of the most numerous and ubiquitous group of plant secondary metabolites with many biological activities. The aim of the present work was to study the potential antimicrobial and antibiofilm properties of gallic, caffeic, and chlorogenic acids against S. aureus as well to elucidate its mechanism of action. It was concluded that the phenolic acids studied in this work have antistaphylococcal properties. For instance, gallic acid is able to influence the adhesion properties of S. aureus. The phenolic acids tested were also able to inhibit the production of α-hemolysin by this microorganism, with the exception of chlorogenic acid. Regarding its mechanism of action, caffeic acid interferes with the stability of the cell membrane and with the metabolic activity of the cells of S. aureus. PMID:24228999

  11. 1,4-benzoxazin-3-one, 2-benzoxazolinone and gallic acid from Calceolaria thyrsiflora Graham and their antibacterial activity.

    PubMed

    Bravo, Héctor R; Copaja, Sylvia V; Figueroa-Duarte, Sebastián; Lamborot, Madeleine; San Martín, José

    2005-01-01

    Secondary metabolites, DIBOA, HBOA, 7-OH-HBOA, BOA and gallic acid, were isolated and quantified from Calceolaria thyrsiflora Graham, a native medicinal plant of Chile belonging to the Scrophulariaceae family. The highest DIBOA contents were determined in leaves (145 mmol kg(-1) dry wt) and flowers (161 mmol kg(-1) dry wt). Antibacterial activities of DIBOA, HBOA, BOA, gallic acid and infusions of flowers and leaves were determined. The phytomedicinal properties attributed to C. thyrsiflora Graham could be understood on the basis of its antibacterial activity.

  12. General method for the preparation of active esters by palladium-catalyzed alkoxycarbonylation of aryl bromides.

    PubMed

    de Almeida, Angelina M; Andersen, Thomas L; Lindhardt, Anders T; de Almeida, Mauro V; Skrydstrup, Troels

    2015-02-01

    A useful method was developed for the synthesis of active esters by palladium-catalyzed alkoxycarbonylation of (hetero)aromatic bromides. The protocol was general for a range of oxygen nucleophiles including N-hydroxysuccinimide (NHS), pentafluorophenol (PFP), hexafluoroisopropyl alcohol (HFP), 4-nitrophenol, and N-hydroxyphthalimide. A high functional group tolerance was displayed, and several active esters were prepared with good to excellent isolated yields. The protocol was extended to access an important synthetic precursor to the HIV-protease inhibitor, saquinavir, by formation of an NHS ester followed by acyl substitution.

  13. Anomeric selectivity in the synthesis of galloyl esters of D-glucose.

    PubMed

    Binkley, Robert C; Ziepfel, Jessica C; Himmeldirk, Klaus B

    2009-01-26

    The anomeric selectivity of the ester formation between d-glucopyranose and gallic acid was investigated under a variety of conditions. A new protocol was established that allows performing the reaction under conditions where mutarotation is very slow. Highly alpha- or beta-selective transformations are possible when starting with alpha- or beta-d-glucopyranose, respectively. Due to the kinetic anomeric effect, a high alpha-selectivity is more difficult to achieve than a high beta-selectivity. The new methodology presented in this article was compared with established procedures for the synthesis of gallotannins. In addition to the advantages of a high yield and an easy purification protocol, the new procedure uniquely allowed for a highly selective synthesis of alpha-products.

  14. Electrochromic display device

    NASA Astrophysics Data System (ADS)

    Nicholson, M. M.

    1984-07-01

    This invention relates to electrochromic devices. In one aspect it relates to electrically controllable display devices. In another aspect it relates to electrically tunable optical or light filters. In yet another aspect it relates to a chemical sensor device which employs a color changing film. There are many uses for electrically controllable display devices. A number of such devices have been in commercial use for some time. These display devices include liquid crystal displays, light emitting diode displays, plasma displays, and the like. Light emitting diode displays and plasma display panels both suffer from the fact that they are active. Light emissive devices which require substantial power for their operation, In addition, it is difficult to fabricate light emitting diode displays in a manner which renders them easily distinguishable under bright ambient illumination. Liquid crystal displays suffer from the disadvantage that they are operative only over a limited temperature range and have substantially no memory within the liquid crystal material.

  15. System status display information

    NASA Technical Reports Server (NTRS)

    Summers, L. G.; Erickson, J. B.

    1984-01-01

    The system Status Display is an electronic display system which provides the flight crew with enhanced capabilities for monitoring and managing aircraft systems. Guidelines for the design of the electronic system displays were established. The technical approach involved the application of a system engineering approach to the design of candidate displays and the evaluation of a Hernative concepts by part-task simulation. The system engineering and selection of candidate displays are covered.

  16. An Efficient Protocol for Preparation of Gallic Acid from Terminalia bellirica (Gaertn.) Roxb by Combination of Macroporous Resin and Preparative High-Performance Liquid Chromatography.

    PubMed

    Zou, Denglang; Chen, Tao; Chen, Chen; Li, Hongmei; Liu, Yongling; Li, Yulin

    2016-08-01

    In this article, macroporous resin column chromatography and preparative high-performance liquid chromatography were applied for preparation of gallic acid from Terminalia bellirica (Gaertn.) Roxb. In the first step, six kinds of resins were investigated by adsorption and desorption tests and AB-8 macroporous resin was selected for the enrichment of gallic acid. As a result, 20 g of gallic acid at a purity of 71% could be separated from 100 g of crude extract in which the content of gallic acid was 16.7% and the recovery of gallic acid reached 85.0%. In the second step, preparative high-performance liquid chromatography was selected to purify gallic acid. As a result, 640 mg of gallic acid at a purity of 99.1% was obtained from 1 g of sample in 35 min. The results demonstrated that macroporous resin coupled with preparative high-performance liquid chromatography was suitable for preparation of gallic acid from T. bellirica (Gaertn.) Roxb. PMID:27076561

  17. An Efficient Protocol for Preparation of Gallic Acid from Terminalia bellirica (Gaertn.) Roxb by Combination of Macroporous Resin and Preparative High-Performance Liquid Chromatography.

    PubMed

    Zou, Denglang; Chen, Tao; Chen, Chen; Li, Hongmei; Liu, Yongling; Li, Yulin

    2016-08-01

    In this article, macroporous resin column chromatography and preparative high-performance liquid chromatography were applied for preparation of gallic acid from Terminalia bellirica (Gaertn.) Roxb. In the first step, six kinds of resins were investigated by adsorption and desorption tests and AB-8 macroporous resin was selected for the enrichment of gallic acid. As a result, 20 g of gallic acid at a purity of 71% could be separated from 100 g of crude extract in which the content of gallic acid was 16.7% and the recovery of gallic acid reached 85.0%. In the second step, preparative high-performance liquid chromatography was selected to purify gallic acid. As a result, 640 mg of gallic acid at a purity of 99.1% was obtained from 1 g of sample in 35 min. The results demonstrated that macroporous resin coupled with preparative high-performance liquid chromatography was suitable for preparation of gallic acid from T. bellirica (Gaertn.) Roxb.

  18. Seamless tiled display system

    NASA Technical Reports Server (NTRS)

    Dubin, Matthew B. (Inventor); Larson, Brent D. (Inventor); Kolosowsky, Aleksandra (Inventor)

    2006-01-01

    A modular and scalable seamless tiled display apparatus includes multiple display devices, a screen, and multiple lens assemblies. Each display device is subdivided into multiple sections, and each section is configured to display a sectional image. One of the lens assemblies is optically coupled to each of the sections of each of the display devices to project the sectional image displayed on that section onto the screen. The multiple lens assemblies are configured to merge the projected sectional images to form a single tiled image. The projected sectional images may be merged on the screen by magnifying and shifting the images in an appropriate manner. The magnification and shifting of these images eliminates any visual effect on the tiled display that may result from dead-band regions defined between each pair of adjacent sections on each display device, and due to gaps between multiple display devices.

  19. Green tea constituents (-)-epigallocatechin-3-gallate (EGCG) and gallic acid induce topoisomerase I- and topoisomerase II-DNA complexes in cells mediated by pyrogallol-induced hydrogen peroxide.

    PubMed

    López-Lázaro, Miguel; Calderón-Montaño, José Manuel; Burgos-Morón, Estefanía; Austin, Caroline A

    2011-07-01

    Green tea and its major active constituent, (-)-epigallocatechin-3-gallate (EGCG), are in clinical trials for the prevention and treatment of several diseases such as cancer. DNA topoisomerase (topo) poisons are commonly prescribed anticancer drugs that kill cancer cells by inducing topo-DNA complexes. Using purified topoisomerases, previous in vitro studies have shown that EGCG induces the formation of topo-DNA complexes. Because the activity of a drug on purified topoisomerases does not always represent the activity in a cell, we have used an immunofluorescence technique that allows the visualisation of topo I- and topo II-DNA complexes produced in individual cells to evaluate the activity of EGCG on both enzymes. High levels of topo I- and topo II-DNA complexes were observed in K562 leukaemia cells exposed to EGCG. Similar levels of topo I- and topo II-DNA complexes were visualised in cells treated with gallic acid (GA) (the acid part of the EGCG ester). Pyrogallol (PG) also induced topo-DNA complexes with both enzymes, therefore suggesting that the activity of EGCG and GA is mediated by their PG moieties. Catalase prevented both the cytotoxicity and the formation of topo I- and topo II-DNA complexes induced by EGCG, GA, PG and myricetin (a PG-containing flavonoid recently shown to induce topo I- and topo II-DNA complexes in cells), indicating that hydrogen peroxide mediates these activities. Hydrogen peroxide induced topo I- and topo II (α and β)-DNA complexes in a time- and dose-dependent manner. The formation of topo I- and topo II-DNA complexes in cells exposed to hydrogen peroxide correlated well with the induction of apoptosis, suggesting that the topo-DNA complexes induced at long exposure times by the compounds tested in our study may be apoptotic topo-DNA complexes. Finally, we report results suggesting that PG-containing drugs may selectively kill tumour cells by generating hydrogen peroxide.

  20. Mechanism of in situ surface polymerization of gallic acid in an environmental-inspired preparation of carboxylated core-shell magnetite nanoparticles.

    PubMed

    Tóth, Ildikó Y; Szekeres, Márta; Turcu, Rodica; Sáringer, Szilárd; Illés, Erzsébet; Nesztor, Dániel; Tombácz, Etelka

    2014-12-30

    Magnetite nanoparticles (MNPs) with biocompatible coatings are good candidates for MRI (magnetic resonance imaging) contrasting, magnetic hyperthermia treatments, and drug delivery systems. The spontaneous surface induced polymerization of dissolved organic matter on environmental mineral particles inspired us to prepare carboxylated core-shell MNPs by using a ubiquitous polyphenolic precursor. Through the adsorption and in situ surface polymerization of gallic acid (GA), a polygallate (PGA) coating is formed on the nanoparticles (PGA@MNP) with possible antioxidant capacity. The present work explores the mechanism of polymerization with the help of potentiometric acid-base titration, dynamic light scattering (for particle size and zeta potential determination), UV-vis (UV-visible light spectroscopy), FTIR-ATR (Fourier-transformed infrared spectroscopy by attenuated total reflection), and XPS (X-ray photoelectron spectroscopy) techniques. We observed the formation of ester and ether linkages between gallate monomers both in solution and in the adsorbed state. Higher polymers were formed in the course of several weeks both on the surface of nanoparticles and in the dispersion medium. The ratio of the absorbances of PGA supernatants at 400 and 600 nm (i.e., the E4/E6 ratio commonly used to characterize the degree of polymerization of humic materials) was determined to be 4.3, similar to that of humic acids. Combined XPS, dynamic light scattering, and FTIR-ATR results revealed that, prior to polymerization, the GA monomers became oxidized to poly(carboxylic acid)s due to ring opening while Fe(3+) ions reduced to Fe(2+). Our published results on the colloidal and chemical stability of PGA@MNPs are referenced thoroughly in the present work. Detailed studies on biocompatibility, antioxidant property, and biomedical applicability of the particles will be published.

  1. Gallic acid-based indanone derivative interacts synergistically with tetracycline by inhibiting efflux pump in multidrug resistant E. coli.

    PubMed

    Dwivedi, Gaurav Raj; Tiwari, Nimisha; Singh, Aastha; Kumar, Akhil; Roy, Sudeep; Negi, Arvind Singh; Pal, Anirban; Chanda, Debabrata; Sharma, Ashok; Darokar, Mahendra P

    2016-03-01

    The purpose of the present study was to study the synergy potential of gallic acid-based derivatives in combination with conventional antibiotics using multidrug resistant cultures of Escherichia coli. Gallic acid-based derivatives significantly reduced the MIC of tetracycline against multidrug resistant clinical isolate of E. coli. The best representative, 3-(3',4,'5'-trimethoxyphenyl)-4,5,6-trimethoxyindanone-1, an indanone derivative of gallic acid, was observed to inhibit ethidium bromide efflux and ATPase which was also supported by in silico docking. This derivative extended the post-antibiotic effect and decreased the mutation prevention concentration of tetracycline. This derivative in combination with TET was able to reduce the concentration of TNFα up to 18-fold in Swiss albino mice. This derivative was nontoxic and well tolerated up to 300 mg/kg dose in subacute oral toxicity study in mice. This is the first report of gallic acid-based indanone derivative as drug resistance reversal agent acting through ATP-dependent efflux pump inhibition.

  2. Gallic acid as a protective antioxidant against anthocyanin degradation and color loss in vitamin-C fortified cranberry juice.

    PubMed

    Roidoung, Sunisa; Dolan, Kirk D; Siddiq, Muhammad

    2016-11-01

    The objective of this study was to evaluate different antioxidants for anthocyanin (ACY) retention in vitamin C fortified cranberry juice and assess its quality. Cranberry juice was fortified with 40-80mg/100mL vitamin C and added hesperidin, catechin, and gallic acid at different concentrations. Juice was pasteurized at 85°C for 1min and stored at 23°C for 16days. ACYs, vitamin C, color intensity, and browning index (BI) were evaluated at 2-day intervals. Gallic acid was found to be the most effective antioxidant against ACYs degradation and significantly (p<0.05) increased red color intensity by 37% and ACY concentration by 41%, compared to the control. After 16-day storage, the BI of gallic acid-added juice was significantly lower (0.80 vs 1.00) than the control juice. The outcome of this research provided a potential solution of using gallic acid to preserve a health-beneficial component (ACYs), and endogenous red color in cranberry juice.

  3. Identification of gallic acid based glycoconjugates as a novel tubulin polymerization inhibitors.

    PubMed

    Upadhyaya, Kapil; Hamidullah; Singh, Kartikey; Arun, Ashutosh; Shukla, Mahendra; Srivastava, Neetika; Ashraf, Raghib; Sharma, Abhisheak; Mahar, Rohit; Shukla, Sanjeev K; Sarkar, Jayanta; Ramachandran, Ravishankar; Lal, Jawahar; Konwar, Rituraj; Tripathi, Rama Pati

    2016-01-28

    A novel class of gallic acid based glycoconjugates were designed and synthesized as potential anticancer agents. Among all the compounds screened, compound 2a showed potent anticancer activity against breast cancer cells. The latter resulted in tubulin polymerization inhibition and induced G2/M cell cycle arrest, generation of reactive oxygen species, mitochondrial depolarization and subsequent apoptosis in breast cancer cells. In addition, ultraviolet-visible spectroscopy and fluorescence quenching studies of the compound with tubulin confirmed direct interaction of compounds with tubulin. Molecular modeling studies revealed that it binds at the colchicine binding site in tubulin. Further, 2a also exhibited potent in vivo anticancer activity in LA-7 syngeneic rat mammary tumor model. Current data projects its strong candidature to be developed as anticancer agent.

  4. Solvatochromic behavior of the electronic absorption spectra of gallic acid and some of its azo derivatives

    NASA Astrophysics Data System (ADS)

    Masoud, Mamdouh S.; Hagagg, Sawsan S.; Ali, Alaa E.; Nasr, Nessma M.

    The electronic absorption spectra of gallic acid and its azo derivatives have been studied in various solvents of different polarities. Multiple regression techniques were applied to calculate the regression and correlation coefficients based on an equation that relates the wavenumbers of the absorption band maxima (υmax-) to the solvent parameters; refractive index (n), dielectric constant (D), empirical Kamlet-Taft solvent parameters, π*(dipolarity/polarizability), α (solvent hydrogen-bond donor acidity) and β (solvent hydrogen-bond acceptor basicity). The fitting coefficient obtained from this analysis allows estimating the contribution of each type of interactions relative to total spectral shifts in solution. The dependence of υmax- on the solvent parameters indicates that the obtained bands are affected by specific and non-specific solute-solvent interactions.

  5. Gallic acid induces mitotic catastrophe and inhibits centrosomal clustering in HeLa cells.

    PubMed

    Tan, Si; Guan, Xin; Grün, Christoph; Zhou, Zhiqin; Schepers, Ute; Nick, Peter

    2015-12-25

    Cancer cells divide rapidly, providing medical targets for anticancer agents. The polyphenolic gallic acid (GA) is known to be toxic for certain cancer cells. However, the cellular mode of action has not been elucidated. Therefore, the current study addressed a potential effect of GA on the mitosis of cancer cells. GA inhibited viability of HeLa cells in a dose-dependent and time-dependent manner. We could show, using fluorescence-activated cell sorting (FACS), that this inhibition was accompanied by elevated frequency of cells arrested at the G2/M transition. This cell-cycle arrest was accompanied by mitotic catastrophe, and formation of cells with multiple nuclei. These aberrations were preceded by impaired centrosomal clustering. We arrive at a model of action, where GA inhibits the progression of the cell cycle at the G2/M phase by impairing centrosomal clustering which will stimulate mitotic catastrophe. Thus, GA has potential as compound against cervical cancer.

  6. Characterization of the Interaction between Gallic Acid and Lysozyme by Molecular Dynamics Simulation and Optical Spectroscopy.

    PubMed

    Zhan, Minzhong; Guo, Ming; Jiang, Yanke; Wang, Xiaomeng

    2015-07-01

    The binding interaction between gallic acid (GA) and lysozyme (LYS) was investigated and compared by molecular dynamics (MD) simulation and spectral techniques. The results from spectroscopy indicate that GA binds to LYS to generate a static complex. The binding constants and thermodynamic parameters were calculated. MD simulation revealed that the main driving forces for GA binding to LYS are hydrogen bonding and hydrophobic interactions. The root-mean-square deviation verified that GA and LYS bind to form a stable complex, while the root-mean-square fluctuation results showed that the stability of the GA-LYS complex at 298 K was higher than that at 310 K. The calculated free binding energies from the molecular mechanics/Poisson-Boltzmann surface area method showed that van der Waals forces and electrostatic interactions are the predominant intermolecular forces. The MD simulation was consistent with the spectral experiments. This study provides a reference for future study of the pharmacological mechanism of GA.

  7. Solvatochromic behavior of the electronic absorption spectra of gallic acid and some of its azo derivatives.

    PubMed

    Masoud, Mamdouh S; Hagagg, Sawsan S; Ali, Alaa E; Nasr, Nessma M

    2012-08-01

    The electronic absorption spectra of gallic acid and its azo derivatives have been studied in various solvents of different polarities. Multiple regression techniques were applied to calculate the regression and correlation coefficients based on an equation that relates the wavenumbers of the absorption band maxima (υ(max)(-)) to the solvent parameters; refractive index (n), dielectric constant (D), empirical Kamlet-Taft solvent parameters, π*(dipolarity/polarizability), α (solvent hydrogen-bond donor acidity) and β (solvent hydrogen-bond acceptor basicity). The fitting coefficient obtained from this analysis allows estimating the contribution of each type of interactions relative to total spectral shifts in solution. The dependence of υ(max)(-) on the solvent parameters indicates that the obtained bands are affected by specific and non-specific solute-solvent interactions.

  8. Investigation of gallic acid induced anticancer effect in human breast carcinoma MCF-7 cells.

    PubMed

    Wang, Ke; Zhu, Xue; Zhang, Kai; Zhu, Ling; Zhou, Fanfan

    2014-09-01

    Gallic acid (GA), a polyhydroxylphenolic compound abundantly distributed in plants, fruits, and foods, has been reported to have various biological activities including an anticancer effect. In this study, we extensively investigated the anticancer effect of GA in human breast carcinoma MCF-7 cells. Our study indicated that treatment with GA resulted in inhibition of proliferation and induction of apoptosis in MCF-7 cells. Then, the molecular mechanism of GA's apoptotic action in MCF-7 cells was further investigated. The results revealed that GA induced apoptosis by triggering the extrinsic or Fas/FasL pathway as well as the intrinsic or mitochondrial pathway. Furthermore, the apoptotic signaling induced by GA was amplified by cross-link between the two pathways. Taken together, our findings may be useful for understanding the mechanism of action of GA on breast cancer cells and provide new insights into the possible application of such compound and its derivatives in breast cancer therapy.

  9. Docking analysis of gallic acid derivatives as HIV-1 protease inhibitors.

    PubMed

    Singh, Anjali; Pal, Tapan Kumar

    2015-01-01

    HIV-1 Protease (HIV-1 PR) enzymes are essential for accurate assembly and maturation of infectious HIV retroviruses. The significant role of HIV-1 protease in viral replication has made it a potential drug target. In the recent past, phytochemical Gallic Acid (GA) derivatives have been screened for protease inhibitor activity. The present work aims to design and evaluate potential GA-based HIV-1 PR phytoinhibitors by docking approach. The ligands were prepared by ChemDraw and docking was performed in HEX software. In this present study, one of the GA analogues (GA4) emerged as a potent drug candidate for HIV-1 PR inhibition, and docking results showed it to be comparable with anti-HIV drugs, darunavir and amprenavir. The GA4 derivative provided a lead for designing more effective HIV-1 PR inhibitors.

  10. Phenolics of Arbutus unedo L. (Ericaceae) fruits: identification of anthocyanins and gallic acid derivatives.

    PubMed

    Pawlowska, Agata Maria; De Leo, Marinella; Braca, Alessandra

    2006-12-27

    Arbutus unedo L., the strawberry tree (Ericaceae family), is an evergreen shrub or small tree, typical of the Mediterranean fringe and climate. The aim of the present study was to evaluate the profile of the phenolic constituents of A. unedo fruits. Seven compounds were purified by Sephadex LH-20 column chromatography of the MeOH extract followed by HPLC and were characterized as arbutin, beta-D-glucogalline, gallic acid 4-O-beta-D-glucopyranoside, 3-O-galloylquinic acid, 5-O-galloylquinic acid, 3-O-galloylshikimic acid, and 5-O-galloylshikimic acid, by means of NMR and ESI-MS analyses. Moreover, LC-PDA-MS analysis of the red pigment of A. unedo fruits revealed the presence of three anthocyanins recognized as cyanidin 3-O-beta-D-galactopyranoside, delphinidin 3-O-beta-D-glucopyranoside, and cyanidin 3-O-beta-D-arabinopyranoside. These pigments were also quantified. PMID:17177565

  11. Encapsulation of gallic acid/cyclodextrin inclusion complex in electrospun polylactic acid nanofibers: Release behavior and antioxidant activity of gallic acid.

    PubMed

    Aytac, Zeynep; Kusku, Semran Ipek; Durgun, Engin; Uyar, Tamer

    2016-06-01

    Cyclodextrin-inclusion complexes (CD-ICs) possess great prominence in food and pharmaceutical industries due to their enhanced ability for stabilization of active compounds during processing, storage and usage. Here, CD-IC of gallic acid (GA) with hydroxypropyl-beta-cyclodextrin (GA/HPβCD-IC) was prepared and then incorporated into polylactic acid (PLA) nanofibers (PLA/GA/HPβCD-IC-NF) using electrospinning technique to observe the effect of CD-ICs in the release behavior of GA into three different mediums (water, 10% ethanol and 95% ethanol). The GA incorporated PLA nanofibers (PLA/GA-NFs) were served as control. Phase solubility studies showed an enhanced solubility of GA with increasing amount of HPβCD. The detailed characterization techniques (XRD, TGA and (1)H-NMR) confirmed the formation of inclusion complex between GA and HPβCD. Computational modeling studies indicated that the GA made an efficient complex with HPβCD at 1:1 either in vacuum or aqueous system. SEM images revealed the bead-free and uniform morphology of PLA/GA/HPβCD-IC-NF. The release studies of GA from PLA/GA/HPβCD-IC-NF and PLA/GA-NF were carried out in water, 10% ethanol and 95% ethanol, and the findings revealed that PLA/GA/HPβCD-IC-NF has released much more amount of GA in water and 10% ethanol system when compared to PLA/GA-NF. In addition, GA was released slowly from PLA/GA/HPβCD-IC-NF into 95% ethanol when compared to PLA/GA-NF. It was also observed that electrospinning process had no negative effect on the antioxidant activity of GA when GA was incorporated in PLA nanofibers.

  12. Encapsulation of gallic acid/cyclodextrin inclusion complex in electrospun polylactic acid nanofibers: Release behavior and antioxidant activity of gallic acid.

    PubMed

    Aytac, Zeynep; Kusku, Semran Ipek; Durgun, Engin; Uyar, Tamer

    2016-06-01

    Cyclodextrin-inclusion complexes (CD-ICs) possess great prominence in food and pharmaceutical industries due to their enhanced ability for stabilization of active compounds during processing, storage and usage. Here, CD-IC of gallic acid (GA) with hydroxypropyl-beta-cyclodextrin (GA/HPβCD-IC) was prepared and then incorporated into polylactic acid (PLA) nanofibers (PLA/GA/HPβCD-IC-NF) using electrospinning technique to observe the effect of CD-ICs in the release behavior of GA into three different mediums (water, 10% ethanol and 95% ethanol). The GA incorporated PLA nanofibers (PLA/GA-NFs) were served as control. Phase solubility studies showed an enhanced solubility of GA with increasing amount of HPβCD. The detailed characterization techniques (XRD, TGA and (1)H-NMR) confirmed the formation of inclusion complex between GA and HPβCD. Computational modeling studies indicated that the GA made an efficient complex with HPβCD at 1:1 either in vacuum or aqueous system. SEM images revealed the bead-free and uniform morphology of PLA/GA/HPβCD-IC-NF. The release studies of GA from PLA/GA/HPβCD-IC-NF and PLA/GA-NF were carried out in water, 10% ethanol and 95% ethanol, and the findings revealed that PLA/GA/HPβCD-IC-NF has released much more amount of GA in water and 10% ethanol system when compared to PLA/GA-NF. In addition, GA was released slowly from PLA/GA/HPβCD-IC-NF into 95% ethanol when compared to PLA/GA-NF. It was also observed that electrospinning process had no negative effect on the antioxidant activity of GA when GA was incorporated in PLA nanofibers. PMID:27040215

  13. Protective Effects of Gallic Acid against Streptozotocin-induced Oxidative Damage in Rat Striatum.

    PubMed

    Naghizadeh, B; Mansouri, M T

    2015-10-01

    The present study aimed to investigate the protective effects of gallic acid (GA) against ICV STZ-induced oxidative damage in the rat striatum. Animals were randomly divided into 4 groups (8 each). Group 1 (Sham), were injected ICV on day 1 and 3 with artificial CSF and treated with normal saline (2 ml/kg, p.o.). Group 2 (sham+GA), were injected ICV on day 1 and 3 with artificial CSF and treated with GA (30 mg/kg, p.o.) for 26 days. Group 3 (lesion) were injected with ICV-STZ (3 mg/kg bilaterally, on day 1 and 3) and received normal saline (2 ml/kg, p.o.) as vehicle. Group 4 (lesion+GA), were injected with ICV-STZ (3 mg/kg bilaterally, on day 1 and 3) and treated with gallic acid (30 mg/kg, p.o.) once daily for 26 days starting 5 days before the first injection of ICV STZ. The homogenized striatum was used for measuring thiobarbituric acid reactive species (TBARS) and total thiol contents, glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD) activities. The results showed that ICV STZ-injection increased the level of TBARS (+69.3%) and decreased total thiol concentration (-48.8%), GPx (-47.3%), CAT (-47.1%) and SOD (-30.7%) activities. In contrast, chronic administration of GA significantly prevented the biochemical alterations in the ICV-STZ rats. These findings highlight the beneficial role of GA via enhancement of cerebral antioxidant defense system.

  14. EMU helmet mounted display

    NASA Technical Reports Server (NTRS)

    Marmolejo, Jose (Inventor); Smith, Stephen (Inventor); Plough, Alan (Inventor); Clarke, Robert (Inventor); Mclean, William (Inventor); Fournier, Joseph (Inventor)

    1990-01-01

    A helmet mounted display device is disclosed for projecting a display on a flat combiner surface located above the line of sight where the display is produced by two independent optical channels with independent LCD image generators. The display has a fully overlapped field of view on the combiner surface and the focus can be adjusted from a near field of four feet to infinity.

  15. Fiberite 954: cyanate ester systems

    NASA Astrophysics Data System (ADS)

    Almen, G. R.; Mackenzie, P. D.; Malhotra, Vinay; Maskell, R. K.

    1992-09-01

    Cost and weight savings achieved by the use of composites have allowed these materials to displace their metal counterparts in space applications. Epoxy matrix based carbon fiber reinforced composites, such as Fiberite 934, have been used for a number of years. Relative to these systems, cyanate esters offer a number of unique attributes such as excellent hydrophobicity and electrical properties, reduced residual stress and better microcrack resistance, and improved radiation resistance. The significant reduction in water sorption and the low response to uptake make it possible to achieve much improved dimensional stability and reduced outgassing. These features may be used to advantage in electro-optical applications in space. ICI Fiberite has developed cyanate ester based prepreg systems that are penetrating the satellite, military radome and structural aerospace markets. Features of these systems will be presented and the properties of the cyanate ester based prepreg, Fiberite 954- 3, will be compared to those of Fiberite 934.

  16. XVD Image Display Program

    NASA Technical Reports Server (NTRS)

    Deen, Robert G.; Andres, Paul M.; Mortensen, Helen B.; Parizher, Vadim; McAuley, Myche; Bartholomew, Paul

    2009-01-01

    The XVD [X-Windows VICAR (video image communication and retrieval) Display] computer program offers an interactive display of VICAR and PDS (planetary data systems) images. It is designed to efficiently display multiple-GB images and runs on Solaris, Linux, or Mac OS X systems using X-Windows.

  17. Screens and Displays.

    ERIC Educational Resources Information Center

    Edstrom, Malin

    1987-01-01

    Discusses the characteristics of different computer screen technologies including the possible harmful effects on health of cathode ray tube (CRT) terminals. CRT's are compared to other technologies including liquid crystal displays, plasma displays, electroluminiscence displays, and light emitting diodes. A chart comparing the different…

  18. Digital video display system

    NASA Technical Reports Server (NTRS)

    Zygielbaum, A. I.; Martin, W. L.; Engle, A.

    1973-01-01

    System displays image data in real time on 120,000-element raster scan with 2, 4, or 8 shades of grey. Designed for displaying planetary range Doppler data, system can be used for X-Y plotting, displaying alphanumerics, and providing image animation.

  19. The anti-inflammatory and anti-apoptotic effects of gallic acid against mucosal inflammation- and erosions-induced by gastric ischemia-reperfusion in rats

    PubMed Central

    Mard, Seyyed Ali; Mojadami, Shahnaz; Farbood, Yaghoob; Gharib Naseri, Mohammad Kazem

    2015-01-01

    The present study aimed to evaluate the protective effect of gallic acid on gastric mucosal lesions caused by ischemia-reperfusion (I/R) injury in rat. Forty male rats were randomly divided into sham, control (I/R injury) and three gallic acid-pretreated groups. To induce I/R lesions, the celiac artery was clamped for 30 min and then the clamp was removed to allow reperfusion for 6 hr. Pretreated rats received gallic acid (15, 30 or 60 mg kg-1, intraperitoneally) 30 min prior to the induction of I/R injury. Macroscopic and microscopic evaluations of the areas of ulceration were compared. Samples of gastric mucosa were collected to evaluate the protein expression of pro-apoptotic factor, caspase-3, and pro-inflammatory enzyme, inducible nitric oxide synthase (iNOS) using western blot. Pretreatment with gallic acid decreased the total area of gastric lesions. Gallic acid at 30 mg kg-1 decreased the levels of protein expression of caspase-3 and iNOS induced by I/R injury. Our findings showed the protective effect of gallic acid on gastric mucosa against ischemia-reperfusion injury. This effect of gallic acid was mainly mediated by reducing protein expression of iNOS and caspase-3. PMID:26973766

  20. Combined Efficacy of Gallic Acid and MiADMSA with Limited Beneficial Effects Over MiADMSA Against Arsenic-induced Oxidative Stress in Mouse.

    PubMed

    Pachauri, Vidhu; Flora, Sjs

    2015-01-01

    Gallic acid is an organic acid known for its antioxidant and anticancer properties. The present study is focused on evaluating the role of gallic acid in providing better therapeutic outcomes against arsenic-induced toxicity. Animals pre-exposed to arsenic were treated with monoisoamyl meso-2,3-dimercaptosuccinic acid (MiADMSA), a new chelating drug, alone and in combination with gallic acid, consecutively for 10 days. The study suggests that (1) gallic acid in presence of MiADMSA is only moderately beneficial against arsenic, (2) monotherapy with gallic acid is more effective than in combination with MiADMSA after arsenic exposure in reducing oxidative injury, and (3) MiADMSA monotherapy as reported previously provides significant therapeutic efficacy against arsenic. Thus, based on the present results, we conclude that gallic acid is effective against arsenic-induced oxidative stress but provides limited additional beneficial effects when administered in combination with MiADMSA. We still recommend that lower doses of gallic acid be evaluated both individually and in combination with MiADMSA, as it might not exhibit the shortcomings we observed with higher doses in this study.

  1. The anti-inflammatory and anti-apoptotic effects of gallic acid against mucosal inflammation- and erosions-induced by gastric ischemia-reperfusion in rats.

    PubMed

    Mard, Seyyed Ali; Mojadami, Shahnaz; Farbood, Yaghoob; Gharib Naseri, Mohammad Kazem

    2015-01-01

    The present study aimed to evaluate the protective effect of gallic acid on gastric mucosal lesions caused by ischemia-reperfusion (I/R) injury in rat. Forty male rats were randomly divided into sham, control (I/R injury) and three gallic acid-pretreated groups. To induce I/R lesions, the celiac artery was clamped for 30 min and then the clamp was removed to allow reperfusion for 6 hr. Pretreated rats received gallic acid (15, 30 or 60 mg kg(-1), intraperitoneally) 30 min prior to the induction of I/R injury. Macroscopic and microscopic evaluations of the areas of ulceration were compared. Samples of gastric mucosa were collected to evaluate the protein expression of pro-apoptotic factor, caspase-3, and pro-inflammatory enzyme, inducible nitric oxide synthase (iNOS) using western blot. Pretreatment with gallic acid decreased the total area of gastric lesions. Gallic acid at 30 mg kg(-1) decreased the levels of protein expression of caspase-3 and iNOS induced by I/R injury. Our findings showed the protective effect of gallic acid on gastric mucosa against ischemia-reperfusion injury. This effect of gallic acid was mainly mediated by reducing protein expression of iNOS and caspase-3.

  2. Combined Efficacy of Gallic Acid and MiADMSA with Limited Beneficial Effects Over MiADMSA Against Arsenic-induced Oxidative Stress in Mouse

    PubMed Central

    Pachauri, Vidhu; Flora, SJS

    2015-01-01

    Gallic acid is an organic acid known for its antioxidant and anticancer properties. The present study is focused on evaluating the role of gallic acid in providing better therapeutic outcomes against arsenic-induced toxicity. Animals pre-exposed to arsenic were treated with monoisoamyl meso-2,3-dimercaptosuccinic acid (MiADMSA), a new chelating drug, alone and in combination with gallic acid, consecutively for 10 days. The study suggests that (1) gallic acid in presence of MiADMSA is only moderately beneficial against arsenic, (2) monotherapy with gallic acid is more effective than in combination with MiADMSA after arsenic exposure in reducing oxidative injury, and (3) MiADMSA monotherapy as reported previously provides significant therapeutic efficacy against arsenic. Thus, based on the present results, we conclude that gallic acid is effective against arsenic-induced oxidative stress but provides limited additional beneficial effects when administered in combination with MiADMSA. We still recommend that lower doses of gallic acid be evaluated both individually and in combination with MiADMSA, as it might not exhibit the shortcomings we observed with higher doses in this study. PMID:26339189

  3. Cytoplasmic bacteriophage display system

    DOEpatents

    Studier, F. William; Rosenberg, Alan H.

    1998-06-16

    Disclosed are display vectors comprising DNA encoding a portion of a structural protein from a cytoplasmic bacteriophage, joined covalently to a protein or peptide of interest. Exemplified are display vectors wherein the structural protein is the T7 bacteriophage capsid protein. More specifically, in the exemplified display vectors the C-terminal amino acid residue of the portion of the capsid protein is joined to the N-terminal residue of the protein or peptide of interest. The portion of the T7 capsid protein exemplified comprises an N-terminal portion corresponding to form 10B of the T7 capsid protein. The display vectors are useful for high copy number display or lower copy number display (with larger fusion). Compositions of the type described herein are useful in connection with methods for producing a virus displaying a protein or peptide of interest.

  4. Cytoplasmic bacteriophage display system

    DOEpatents

    Studier, F.W.; Rosenberg, A.H.

    1998-06-16

    Disclosed are display vectors comprising DNA encoding a portion of a structural protein from a cytoplasmic bacteriophage, joined covalently to a protein or peptide of interest. Exemplified are display vectors wherein the structural protein is the T7 bacteriophage capsid protein. More specifically, in the exemplified display vectors the C-terminal amino acid residue of the portion of the capsid protein is joined to the N-terminal residue of the protein or peptide of interest. The portion of the T7 capsid protein exemplified comprises an N-terminal portion corresponding to form 10B of the T7 capsid protein. The display vectors are useful for high copy number display or lower copy number display (with larger fusion). Compositions of the type described herein are useful in connection with methods for producing a virus displaying a protein or peptide of interest. 1 fig.

  5. Esters of 3,4-dihydroxybenzoic acid, highly effective inhibitors of the sn-glycerol-3-phosphate oxidase of Trypanosoma brucei brucei.

    PubMed

    Grady, R W; Bienen, E J; Clarkson, A B

    1986-10-01

    Alkyl esters of 3,4-dihydroxybenzoic acid are inhibitors of the sn-glycerol-3-phosphate oxidase system of Trypanosoma brucei brucei in vitro and have significant trypanocidal activity in vivo when combined with glycerol. While the parent acid has little inhibitory activity in vitro, the esters are highly active with activity increasing as the chain length of the esterifying alcohol increases. The n-dodecyl ester was more than 400 times as active as salicylhydroxamic acid and 15 times more active than the corresponding p-n-alkyloxybenzhydroxamic acid, one of the most active sn-glycerol-3-phosphate oxidase inhibitors previously reported. When combined with glycerol (to block an alternative pathway of glycolysis) and tested in vitro against intact parasites, this ester was 100 times more effective than salicylhydroxamic acid and 10 times more effective than p-n-dodecyloxybenzhydroxamic acid. It was also active against T. b. brucei in mice when combined with glycerol whereas the latter compound was not. Esters of 3,4,5-trihydroxybenzoic acid (gallic acid) were also highly active while those of 2,3-dihydroxybenzoic acid were much less inhibitory and those of 2,5-dihydroxybenzoic acid were inactive. A related compound, 2',4',5'-trihydroxybutyrophenone, was also active as predicted by its structure but was too toxic to be of interest as a drug candidate.

  6. Liquid Crystalline Thermosets from Ester, Ester-imide, and Ester-amide Oligomers

    NASA Technical Reports Server (NTRS)

    Dingemans, Theodorus J. (Inventor); Weiser, Erik S. (Inventor); St. Clair, Terry L. (Inventor)

    2009-01-01

    Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,000 grams per mole. The end-capped liquid crystaloligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oli-gomers are stable forup to an hour in the melt phase. They are highly processable by a variety of melt process shape forming and blending techniques. Once processed and shaped, the end-capped liquid crystal oigomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures.

  7. Influence of pH on the speciation of copper(II) in reactions with the green tea polyphenols, epigallocatechin gallate and gallic acid.

    PubMed

    Pirker, Katharina F; Baratto, Maria Camilla; Basosi, Riccardo; Goodman, Bernard A

    2012-07-01

    Changes in speciation of copper(II) in reactions with epigallocatechin gallate (EGCG) and gallic acid (GA) as a function of pH have been investigated by multifrequency (X- and S-band) EPR spectroscopy in the fluid and frozen states. The EPR spectra show the formation of three distinct mononuclear species with each of the polyphenols, and these are interpreted in terms of one mono- and two bis-complexes. However, di- or polymeric complexes dominate the Cu(II) speciation in the pH range 4-8, and it is only at alkaline pH values that these mononuclear complexes make appreciable contributions to the metal speciation. Each mononuclear complex displays linewidth anisotropy in fluid solution as a consequence of incomplete averaging of the spin Hamiltonian parameters through molecular motion. Rotational correlation times for the individual complexes have been estimated by analysing the lineshape anisotropy of the fluid solution spectra using parameters determined by simulation of the rigid limit spectra. These show that the molecular masses increase with increasing pH, indicating either coordination of increasing numbers of polyphenol molecules as ligands to the copper or the increasing involvement of polyphenol dimers as ligands in the copper coordination sphere.

  8. Dmp53, basket and drICE gene knockdown and polyphenol gallic acid increase life span and locomotor activity in a Drosophila Parkinson’s disease model

    PubMed Central

    Ortega-Arellano, Hector Flavio; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

    2013-01-01

    Understanding the mechanism(s) by which dopaminergic (DAergic) neurons are eroded in Parkinson’s disease (PD) is critical for effective therapeutic strategies. By using the binary tyrosine hydroxylase (TH)-Gal4/UAS-X RNAi Drosophila melanogaster system, we report that Dmp53, basket and drICE gene knockdown in dopaminergic neurons prolong life span (p < 0.05; log-rank test) and locomotor activity (p < 0.05; χ2 test) in D. melanogaster lines chronically exposed to (1 mM) paraquat (PQ, oxidative stress (OS) generator) compared to untreated transgenic fly lines. Likewise, knockdown flies displayed higher climbing performance than control flies. Amazingly, gallic acid (GA) significantly protected DAergic neurons, ameliorated life span, and climbing abilities in knockdown fly lines treated with PQ compared to flies treated with PQ only. Therefore, silencing specific gene(s) involved in neuronal death might constitute an excellent tool to study the response of DAergic neurons to OS stimuli. We propose that a therapy with antioxidants and selectively “switching off” death genes in DAergic neurons could provide a means for pre-clinical PD individuals to significantly ameliorate their disease condition. PMID:24385865

  9. 40 CFR 721.3034 - Methylamine esters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Methylamine esters. 721.3034 Section... Substances § 721.3034 Methylamine esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as methylamine esters (PMN P-94-982) is...

  10. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  11. 40 CFR 721.3034 - Methylamine esters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Methylamine esters. 721.3034 Section... Substances § 721.3034 Methylamine esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as methylamine esters (PMN P-94-982) is...

  12. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  13. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  14. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  15. 40 CFR 721.3034 - Methylamine esters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Methylamine esters. 721.3034 Section... Substances § 721.3034 Methylamine esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as methylamine esters (PMN P-94-982) is...

  16. 40 CFR 721.2805 - Acrylate ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. Link to an amendment published at 79 FR 34637, June 18, 2014. (a) Chemical substance and... ester (PMN P-96-824) is subject to reporting under this section for the significant new uses...

  17. 40 CFR 721.3034 - Methylamine esters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Methylamine esters. 721.3034 Section... Substances § 721.3034 Methylamine esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as methylamine esters (PMN P-94-982) is...

  18. 40 CFR 721.3034 - Methylamine esters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Methylamine esters. 721.3034 Section... Substances § 721.3034 Methylamine esters. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as methylamine esters (PMN P-94-982) is...

  19. Virtual acoustics displays

    NASA Technical Reports Server (NTRS)

    Wenzel, Elizabeth M.; Fisher, Scott S.; Stone, Philip K.; Foster, Scott H.

    1991-01-01

    The real time acoustic display capabilities are described which were developed for the Virtual Environment Workstation (VIEW) Project at NASA-Ames. The acoustic display is capable of generating localized acoustic cues in real time over headphones. An auditory symbology, a related collection of representational auditory 'objects' or 'icons', can be designed using ACE (Auditory Cue Editor), which links both discrete and continuously varying acoustic parameters with information or events in the display. During a given display scenario, the symbology can be dynamically coordinated in real time with 3-D visual objects, speech, and gestural displays. The types of displays feasible with the system range from simple warnings and alarms to the acoustic representation of multidimensional data or events.

  20. Polyplanar optic display

    SciTech Connect

    Veligdan, J.; Biscardi, C.; Brewster, C.; DeSanto, L.; Beiser, L.

    1997-07-01

    The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. This display screen is 2 inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. The new display uses a 100 milliwatt green solid state laser (532 nm) as its optical source. In order to produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments, Inc. A variable astigmatic focusing system is used to produce a stigmatic image on the viewing face of the POD. In addition to the optical design, the authors discuss the electronic interfacing to the DLP{trademark} chip, the opto-mechanical design and viewing angle characteristics.

  1. Display innovations through glass

    NASA Astrophysics Data System (ADS)

    Hamilton, Lori L.

    2016-03-01

    Prevailing trends in thin, lightweight, high-resolution, and added functionality, such as touch sensing, continue to drive innovation in the display market. While display volumes grow, so do consumers’ need for portability, enhanced optical performance, and mechanical reliability. Technical advancements in glass design and process have enabled display innovations in these areas while supporting industry growth. Opportunities for further innovation remain open for glass manufacturers to drive new applications, enhanced functionality, and increased demand.

  2. Displaying Data As Movies

    NASA Technical Reports Server (NTRS)

    Moore, Judith G.

    1992-01-01

    NMSB Movie computer program displays large sets of data (more than million individual values). Presentation dynamic, rapidly displaying sequential image "frames" in main "movie" window. Any sequence of two-dimensional sets of data scaled between 0 and 255 (1-byte resolution) displayed as movie. Time- or slice-wise progression of data illustrated. Originally written to present data from three-dimensional ultrasonic scans of damaged aerospace composite materials, illustrates data acquired by thermal-analysis systems measuring rates of heating and cooling of various materials. Developed on Macintosh IIx computer with 8-bit color display adapter and 8 megabytes of memory using Symantec Corporation's Think C, version 4.0.

  3. Interactive holographic display

    NASA Astrophysics Data System (ADS)

    Son, Jung-Young; Lee, Beam-Ryeol; Kim, Jin-Woong; Chernyshov, Oleksii O.; Park, Min-Chul

    2014-06-01

    A holographic display which is capable of displaying floating holographic images is introduced. The display is for user interaction with the image on the display. It consists of two parts; multiplexed holographic image generation and a spherical mirror. The time multiplexed image from 2 X 10 DMD frames appeared on PDLC screen is imaged by the spherical mirror and becomes a floating image. This image is combined spatially with two layered TV images appearing behind. Since the floating holographic image has a real spatial position and depth, it allows a user to interact with the image.

  4. JAVA Stereo Display Toolkit

    NASA Technical Reports Server (NTRS)

    Edmonds, Karina

    2008-01-01

    This toolkit provides a common interface for displaying graphical user interface (GUI) components in stereo using either specialized stereo display hardware (e.g., liquid crystal shutter or polarized glasses) or anaglyph display (red/blue glasses) on standard workstation displays. An application using this toolkit will work without modification in either environment, allowing stereo software to reach a wider audience without sacrificing high-quality display on dedicated hardware. The toolkit is written in Java for use with the Swing GUI Toolkit and has cross-platform compatibility. It hooks into the graphics system, allowing any standard Swing component to be displayed in stereo. It uses the OpenGL graphics library to control the stereo hardware and to perform the rendering. It also supports anaglyph and special stereo hardware using the same API (application-program interface), and has the ability to simulate color stereo in anaglyph mode by combining the red band of the left image with the green/blue bands of the right image. This is a low-level toolkit that accomplishes simply the display of components (including the JadeDisplay image display component). It does not include higher-level functions such as disparity adjustment, 3D cursor, or overlays all of which can be built using this toolkit.

  5. Linear and branched alkyl-esters and amides of gallic acid and other (mono-, di- and tri-) hydroxy benzoyl derivatives as promising anti-HCV inhibitors.

    PubMed

    Rivero-Buceta, Eva; Carrero, Paula; Doyagüez, Elisa G; Madrona, Andrés; Quesada, Ernesto; Camarasa, María José; Peréz-Pérez, María Jesús; Leyssen, Pieter; Paeshuyse, Jan; Balzarini, Jan; Neyts, Johan; San-Félix, Ana

    2015-03-01

    Linear and branched compounds that contain two, three or five units of galloyl (3,4,5-trihydroxybenzoyl) or its isomer 2,3,4-trihydroxybenzoyl, as well as other mono- or dihydroxybenzoyl moieties have been synthesized. These molecules have been evaluated for their in vitro inhibitory effects against a wide panel of viruses showing preferential activity against HIV and HCV. Our structure-activity relationship studies demonstrated that the 2,3,4-trihydroxybenzoyl moiety provides better antiviral activities than the galloyl (3,4,5-trihydroxybenzoyl) moiety that is present in natural green tea catechins. This observation can be of interest for the further rational exploration of compounds with anti-HCV/HIV properties. The most notable finding with respect to HIV is that the tripodal compounds 43 and 45, with three 2,3,4-trihydroxybenzoyl moieties, showed higher activities than linear compounds with only one or two. With respect to HCV, the linear compounds, 52 and 41, containing a 12 polymethylene chain and two 2,3 di- or 2,3,4 tri-hydroxybenzoyl groups respectively at the ends of the molecule showed good antiviral efficiency. Furthermore, the anti-HCV activity of both compounds was observed at concentrations well below the cytotoxicity threshold. A representative member of these compounds, 41, showed that the anti-HCV activity was largely independent of the genetic make-up of the HCV subgenomic replicon and cell lines used.

  6. Linear and branched alkyl-esters and amides of gallic acid and other (mono-, di- and tri-) hydroxy benzoyl derivatives as promising anti-HCV inhibitors.

    PubMed

    Rivero-Buceta, Eva; Carrero, Paula; Doyagüez, Elisa G; Madrona, Andrés; Quesada, Ernesto; Camarasa, María José; Peréz-Pérez, María Jesús; Leyssen, Pieter; Paeshuyse, Jan; Balzarini, Jan; Neyts, Johan; San-Félix, Ana

    2015-03-01

    Linear and branched compounds that contain two, three or five units of galloyl (3,4,5-trihydroxybenzoyl) or its isomer 2,3,4-trihydroxybenzoyl, as well as other mono- or dihydroxybenzoyl moieties have been synthesized. These molecules have been evaluated for their in vitro inhibitory effects against a wide panel of viruses showing preferential activity against HIV and HCV. Our structure-activity relationship studies demonstrated that the 2,3,4-trihydroxybenzoyl moiety provides better antiviral activities than the galloyl (3,4,5-trihydroxybenzoyl) moiety that is present in natural green tea catechins. This observation can be of interest for the further rational exploration of compounds with anti-HCV/HIV properties. The most notable finding with respect to HIV is that the tripodal compounds 43 and 45, with three 2,3,4-trihydroxybenzoyl moieties, showed higher activities than linear compounds with only one or two. With respect to HCV, the linear compounds, 52 and 41, containing a 12 polymethylene chain and two 2,3 di- or 2,3,4 tri-hydroxybenzoyl groups respectively at the ends of the molecule showed good antiviral efficiency. Furthermore, the anti-HCV activity of both compounds was observed at concentrations well below the cytotoxicity threshold. A representative member of these compounds, 41, showed that the anti-HCV activity was largely independent of the genetic make-up of the HCV subgenomic replicon and cell lines used. PMID:25617695

  7. The chemotaxonomic significance of two bioactive caffeic acid esters, nepetoidins A and B, in the Lamiaceae.

    PubMed

    Grayer, Renée J; Eckert, Maria R; Veitch, Nigel C; Kite, Geoffrey C; Marin, Petar D; Kokubun, Tetsuo; Simmonds, Monique S J; Paton, Alan J

    2003-09-01

    A survey of leaf surface constituents in the family Lamiaceae using HPLC with diode array detection revealed the presence of two characteristic phenolic compounds in many species. The distribution of these phenolics in the Lamiaceae was found to be of taxonomic significance, as they were present in the great majority of species investigated for the subfamily Nepetoideae, including representatives of the well-known genera of culinary herbs, mint, rosemary, sage, thyme and basil. In contrast, they were absent from species of the other subfamilies of Lamiaceae studied and from the related families Verbenaceae, Scrophulariaceae, Acanthaceae and Buddlejaceae. The compounds were isolated from Plectranthus crassus and identified by NMR spectroscopy as the known caffeic acid esters (Z,E)-[2-(3,5-dihydroxyphenyl)ethenyl] 3-(3,4-dihydroxyphenyl)-2-propenoate and (Z,E)-[2-(3,4-dihydroxyphenyl)ethenyl] 3-(3,4-dihydroxyphenyl)-2-propenoate, for which the trivial names nepetoidins A and B are proposed. The presence of this pair of caffeic acid esters adds another character to the chemical, palynological and embryological features distinguishing the Nepetoideae from the other subfamilies of Lamiaceae and related families, and supports the view that the Nepetoideae are a specialised and monophyletic group within the family. Nepetoidin B was shown to have a greater antioxidant activity than gallic, rosmarinic and caffeic acids, and showed activity as an insect phagostimulant. Both compounds were antifungal.

  8. Cyclopropane amino acid ester dipeptide sweeteners.

    PubMed

    Mapelli, C; Newton, M G; Ringold, C E; Stammer, C H

    1987-10-01

    A series of esters of L-aspartyl-1-aminocyclopropane carboxylic acid has been prepared and their sweet tastes determined. The sweetest ester prepared was about 300 times sweeter than sucrose. An attempt to use basic conditions during preparation of the dipeptide allyl ester led to succinimide formation of the aspartyl peptide even though the beta-carboxyl group was protected by a t-butyl ester function. The X-ray structure of the propyl ester (1c) was determined and its conformation is discussed. PMID:3429129

  9. Cyclopropane amino acid ester dipeptide sweeteners.

    PubMed

    Mapelli, C; Newton, M G; Ringold, C E; Stammer, C H

    1987-10-01

    A series of esters of L-aspartyl-1-aminocyclopropane carboxylic acid has been prepared and their sweet tastes determined. The sweetest ester prepared was about 300 times sweeter than sucrose. An attempt to use basic conditions during preparation of the dipeptide allyl ester led to succinimide formation of the aspartyl peptide even though the beta-carboxyl group was protected by a t-butyl ester function. The X-ray structure of the propyl ester (1c) was determined and its conformation is discussed.

  10. Increased production of wax esters in transgenic tobacco plants by expression of a fatty acid reductase:wax synthase gene fusion.

    PubMed

    Aslan, Selcuk; Hofvander, Per; Dutta, Paresh; Sun, Chuanxin; Sitbon, Folke

    2015-12-01

    Wax esters are hydrophobic lipids consisting of a fatty acid moiety linked to a fatty alcohol with an ester bond. Plant-derived wax esters are today of particular concern for their potential as cost-effective and sustainable sources of lubricants. However, this aspect is hampered by the fact that the level of wax esters in plants generally is too low to allow commercial exploitation. To investigate whether wax ester biosynthesis can be increased in plants using transgenic approaches, we have here exploited a fusion between two bacterial genes together encoding a single wax ester-forming enzyme, and targeted the resulting protein to chloroplasts in stably transformed tobacco (Nicotiana benthamiana) plants. Compared to wild-type controls, transgenic plants showed both in leaves and stems a significant increase in the total level of wax esters, being eight-fold at the whole plant level. The profiles of fatty acid methyl ester and fatty alcohol in wax esters were related, and C16 and C18 molecules constituted predominant forms. Strong transformants displayed certain developmental aberrations, such as stunted growth and chlorotic leaves and stems. These negative effects were associated with an accumulation of fatty alcohols, suggesting that an adequate balance between formation and esterification of fatty alcohols is crucial for a high wax ester production. The results show that wax ester engineering in transgenic plants is feasible, and suggest that higher yields may become achieved in the near future.

  11. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices

    NASA Astrophysics Data System (ADS)

    Justino, Licínia L. G.; Reva, Igor; Fausto, Rui

    2016-07-01

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N2, Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated.

  12. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices.

    PubMed

    Justino, Licínia L G; Reva, Igor; Fausto, Rui

    2016-07-01

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N2, Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated. PMID:27394105

  13. Thermally and vibrationally induced conformational isomerizations, infrared spectra, and photochemistry of gallic acid in low-temperature matrices.

    PubMed

    Justino, Licínia L G; Reva, Igor; Fausto, Rui

    2016-07-01

    Near-infrared (near-IR) narrowband selective vibrational excitation and annealing of gallic acid (3,4,5-trihydroxybenzoic acid) isolated in cryogenic matrices were used to induce interconversions between its most stable conformers. The isomerizations were probed by infrared spectroscopy. An extensive set of quantum chemical calculations, carried out at the DFT(B3LYP)/6-311++G(d,p) level of approximation, was used to undertake a detailed analysis of the ground state potential energy surface of the molecule. This investigation of the molecule conformational space allowed extracting mechanistic insights into the observed annealing- or near-IR-induced isomerization processes. The infrared spectra of the two most stable conformers of gallic acid in N2, Xe, and Ar matrices were fully assigned. Finally, the UV-induced photochemistry of the matrix isolated compound was investigated.

  14. Mechanism of gallic acid biosynthesis in bacteria (Escherichia coli) and walnut (Juglans regia).

    PubMed

    Muir, Ryann M; Ibáñez, Ana M; Uratsu, Sandra L; Ingham, Elizabeth S; Leslie, Charles A; McGranahan, Gale H; Batra, Neelu; Goyal, Sham; Joseph, Jorly; Jemmis, Eluvathingal D; Dandekar, Abhaya M

    2011-04-01

    Gallic acid (GA), a key intermediate in the synthesis of plant hydrolysable tannins, is also a primary anti-inflammatory, cardio-protective agent found in wine, tea, and cocoa. In this publication, we reveal the identity of a gene and encoded protein essential for GA synthesis. Although it has long been recognized that plants, bacteria, and fungi synthesize and accumulate GA, the pathway leading to its synthesis was largely unknown. Here we provide evidence that shikimate dehydrogenase (SDH), a shikimate pathway enzyme essential for aromatic amino acid synthesis, is also required for GA production. Escherichia coli (E. coli) aroE mutants lacking a functional SDH can be complemented with the plant enzyme such that they grew on media lacking aromatic amino acids and produced GA in vitro. Transgenic Nicotiana tabacum lines expressing a Juglans regia SDH exhibited a 500% increase in GA accumulation. The J. regia and E. coli SDH was purified via overexpression in E. coli and used to measure substrate and cofactor kinetics, following reduction of NADP(+) to NADPH. Reversed-phase liquid chromatography coupled to electrospray mass spectrometry (RP-LC/ESI-MS) was used to quantify and validate GA production through dehydrogenation of 3-dehydroshikimate (3-DHS) by purified E. coli and J. regia SDH when shikimic acid (SA) or 3-DHS were used as substrates and NADP(+) as cofactor. Finally, we show that purified E. coli and J. regia SDH produced GA in vitro.

  15. Antiobesity effects of Chinese black tea (Pu-erh tea) extract and gallic acid.

    PubMed

    Oi, Yasuyuki; Hou, I-Ching; Fujita, Hiroyuki; Yazawa, Kazunaga

    2012-04-01

    The antiobesity effects of Chinese black tea (Pu-erh tea) and of gallic acid (GA) were investigated using in vitro and in vivo assays. Chinese black tea extract (BTE) and GA inhibited pancreatic lipase activity in a dose-dependent manner in vitro; the IC(inhibitory concentration)(50) values were 101.6 and 9.2 µg/mL, respectively. Black tea extract (50, 100 mg/kg body weight (b.w.)) and GA (15, 45 mg/kg b.w.) significantly suppressed the elevation of blood triglyceride after oral administration of a corn oil emulsion (8 mL oil/kg b.w.) to male ddY mice. Moreover, the antiobesity effects of BTE and GA were also evaluated in a mouse model of diet-induced obesity. Female ddY mice were divided into seven groups; normal diet (ND) group, high fat diet (HFD) group, BTE (0.2% and 0.6% of diets) groups, and GA (0.007%, 0.02% and 0.1% of diets) groups; the experimental groups were fed the test diets for 12 weeks. The BTE 0.6% and GA 0.1% groups showed significant suppression of weight gain. The weight of parametrial adipose tissue was strongly correlated with the body weight. These results suggest that GA contributes to the antiobesity effect of BTE as an active constituent by inhibiting pancreatic lipase activity.

  16. Gallic acid conjugated with gold nanoparticles: antibacterial activity and mechanism of action on foodborne pathogens

    PubMed Central

    Rattanata, Narintorn; Klaynongsruang, Sompong; Leelayuwat, Chanvit; Limpaiboon, Temduang; Lulitanond, Aroonlug; Boonsiri, Patcharee; Chio-Srichan, Sirinart; Soontaranon, Siriwat; Rugmai, Supagorn; Daduang, Jureerut

    2016-01-01

    Foodborne pathogens, including Plesiomonas shigelloides and Shigella flexneri B, are the major cause of diarrheal endemics worldwide. Antibiotic drug resistance is increasing. Therefore, bioactive compounds with antibacterial activity, such as gallic acid (GA), are needed. Gold nanoparticles (AuNPs) are used as drug delivery agents. This study aimed to conjugate and characterize AuNP–GA and to evaluate the antibacterial activity. AuNP was conjugated with GA, and the core–shell structures were characterized by small-angle X-ray scattering and transmission electron microscopy. Antibacterial activity of AuNP–GA against P. shigelloides and S. flexneri B was evaluated by well diffusion method. AuNP–GA bactericidal mechanism was elucidated by Fourier transform infrared microspectroscopic analysis. The results of small-angle X-ray scattering showed that AuNP–GA conjugation was successful. Antibacterial activity of GA against both bacteria was improved by conjugation with AuNP because the minimum inhibitory concentration value of AuNP–GA was significantly decreased (P<0.0001) compared to that of GA. Fourier transform infrared analysis revealed that AuNP–GA resulted in alterations of lipids, proteins, and nucleic acids at the bacterial cell membrane. Our findings show that AuNP–GA has potential for further application in biomedical sciences. PMID:27555764

  17. Skin testing of gallic acid-based hair dye in paraphenylenediamine/paratoluenediamine-reactive patients.

    PubMed

    Choi, Yunseok; Lee, Joon Ho; Kwon, Hyok Bu; An, Susun; Lee, Ai-Young

    2016-07-01

    Incidence of allergic contact dermatitis (ACD) to para-phenylenediamine (PPD)/paratoluenediamine (PTD) hair dyes is increasing. Hair dyes utilizing gallic acid (GA) may be a safe alternative. However, pretesting is recommended. We investigated the contact sensitivity to ingredients of a dye product; GA, monoethanolamine thioglycolate (MT), l-cystein and ferrous sulfate, and an appropriate pretest method in 31 patients reactive to PPD and/or PTD. An open test was performed with the test dye following the patch test. Subsequently, a use test was performed twice, with a 4-week interval. One subject showed a positive reaction to ferrous sulfate in the patch test. Another subject reacted to the first compound alone in the open test. Thirteen subjects manifesting cutaneous lesions from previous regular hair dyeing, showed reactions at the first use of the test dye; and six had reactions with reduced severity at the second test. GA and MT are safe for use in ACD patients reactive to PPD and/or PTD. For predicting contact allergy to hair dyes, the open test appeared to be a better pretest method than the patch test. PMID:26663148

  18. Gallic acid improved behavior, brain electrophysiology, and inflammation in a rat model of traumatic brain injury.

    PubMed

    Sarkaki, Alireza; Farbood, Yaghoub; Gharib-Naseri, Mohammad Kazem; Badavi, Mohammad; Mansouri, Mohammad Taghi; Haghparast, Abbas; Mirshekar, Mohammad Ali

    2015-08-01

    Traumatic brain injury (TBI) is one of the main causes of intellectual and cognitive disabilities. In the clinic it is essential to limit the development of cognitive impairment after TBI. In this study, the effects of gallic acid (GA; 100 mg/kg, per oral, from 7 days before to 2 days after TBI induction) on neurological score, passive avoidance memory, long-term potentiation (LTP) deficits, and levels of proinflammatory cytokines including interleukin-1 beta (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor-α (TNF-α) in the brain have been evaluated. Brain injury was induced following Marmarou's method. Data were analyzed by one-way and repeated measures ANOVA followed by Tukey's post-hoc test. The results indicated that memory was significantly impaired (p < 0.001) in the group treated with TBI + vehicle, together with deterioration of the hippocampal LTP and increased brain tissue levels of IL-1β, IL-6, and TNF-α. GA treatment significantly improved memory and LTP in the TBI rats. The brain tissue levels of IL-1β, IL-6, and TNF-α were significantly reduced (p < 0.001) in the group treated with GA. The results suggest that GA has neuroprotective properties against TBI-induced behavioral, electrophysiological, and inflammatory disorders, probably via the decrease of cerebral proinflammatory cytokines.

  19. Antiviral Effects of Black Raspberry (Rubus coreanus) Seed and Its Gallic Acid against Influenza Virus Infection.

    PubMed

    Lee, Ji-Hye; Oh, Mi; Seok, Jong Hyeon; Kim, Sella; Lee, Dan Bi; Bae, Garam; Bae, Hae-In; Bae, Seon Young; Hong, Young-Min; Kwon, Sang-Oh; Lee, Dong-Hun; Song, Chang-Seon; Mun, Ji Young; Chung, Mi Sook; Kim, Kyung Hyun

    2016-06-06

    Influenza is a serious public health concern worldwide, as it causes significant morbidity and mortality. The emergence of drug-resistant viral strains requires new approaches for the treatment of influenza. In this study, Rubus coreanus seed (RCS) that is left over from the production of wine or juice was found to show antiviral activities against influenza type A and B viruses. Using the time-of-addition plaque assay, viral replication was almost completely abolished by simultaneous treatment with the RCS fraction of less than a 1-kDa molecular weight (RCSF1). One of the polyphenols derived from RCSF1, gallic acid (GA), identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against both influenza type A and B viruses, albeit at relatively high concentrations. RCSF1 was bound to hemagglutinin protein, inhibited hemagglutination significantly and disrupted viral particles, whereas GA was found to only disrupt the viral particles by using transmission electron microscopy. In BALB/c mice infected with influenza virus, oral administration of RCSF1 significantly improved the survival rate and reduced the viral titers in the lungs. Our results demonstrate that RCSF1 and GA show potent and broad antiviral activity against influenza A and B type viruses and are promising sources of agents that target virus particles.

  20. Effect of Gallic Acid on Dementia Type of Alzheimer Disease in Rats: Electrophysiological and Histological Studies

    PubMed Central

    Hajipour, Somayeh; Sarkaki, Alireza; Farbood, Yaghoob; Eidi, Akram; Mortazavi, Pejman; Valizadeh, Zohreh

    2016-01-01

    Introduction: To study the effect of gallic acid (GA) on hippocampal long-term potentiation (LTP) and histological changes in animal model of Alzheimer disease (AD) induced by beta-amyloid (Aβ). Methods: Sixty-four adult male Wistar rats (300±20 g) were divided into 8 groups: 1) Control (Cont); 2) AD; 3) Sham; 4–7) AD+GA (50, 100, and 200 mg/kg for 10 days, orally) or vehicle, 8) Cont+GA100, Aβ (1μg/μL in each site) was infused into hippocampus bilaterally. Changes of amplitude and slope of LTP induced in hippocampal dentate gyrus (DG) were evaluated by high frequency stimulation (HFS) of perforant path (PP). Results: Data showed that LTP amplitude and area under curve significantly impaired in AD rats (P<0.001), while significantly improved in AD rats treated with GA (P<0.05, P<0.01). Conclusion: Current findings suggest that GA reduces neural damage and brain amyloid neuropathology and improves cognitive function via free radicals scavenging and inhibiting oligomerization of Aβ but with no effect on healthy rats. PMID:27303604

  1. Antiviral Effects of Black Raspberry (Rubus coreanus) Seed and Its Gallic Acid against Influenza Virus Infection

    PubMed Central

    Lee, Ji-Hye; Oh, Mi; Seok, Jong Hyeon; Kim, Sella; Lee, Dan Bi; Bae, Garam; Bae, Hae-In; Bae, Seon Young; Hong, Young-Min; Kwon, Sang-Oh; Lee, Dong-Hun; Song, Chang-Seon; Mun, Ji Young; Chung, Mi Sook; Kim, Kyung Hyun

    2016-01-01

    Influenza is a serious public health concern worldwide, as it causes significant morbidity and mortality. The emergence of drug-resistant viral strains requires new approaches for the treatment of influenza. In this study, Rubus coreanus seed (RCS) that is left over from the production of wine or juice was found to show antiviral activities against influenza type A and B viruses. Using the time-of-addition plaque assay, viral replication was almost completely abolished by simultaneous treatment with the RCS fraction of less than a 1-kDa molecular weight (RCSF1). One of the polyphenols derived from RCSF1, gallic acid (GA), identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against both influenza type A and B viruses, albeit at relatively high concentrations. RCSF1 was bound to hemagglutinin protein, inhibited hemagglutination significantly and disrupted viral particles, whereas GA was found to only disrupt the viral particles by using transmission electron microscopy. In BALB/c mice infected with influenza virus, oral administration of RCSF1 significantly improved the survival rate and reduced the viral titers in the lungs. Our results demonstrate that RCSF1 and GA show potent and broad antiviral activity against influenza A and B type viruses and are promising sources of agents that target virus particles. PMID:27275830

  2. Effects of piperine, cinnamic acid and gallic acid on rosuvastatin pharmacokinetics in rats.

    PubMed

    Basu, Sudipta; Jana, Snehasis; Patel, Vandana B; Patel, Hitesh

    2013-10-01

    The purpose of this study was to investigate the potential pharmacokinetic interactions with natural products (such as piperine (PIP), gallic acid (GA) and cinnamic acid (CA)) and rosuvastatin (RSV) (a specific breast cancer resistance protein, BCRP substrate) in rats. In Caco2 cells, the polarized transport of RSV was effectively inhibited by PIP, CA and GA at concentration of 50 μM. After per oral (p.o.) coadministration of PIP, CA and GA (10 mg/kg) significantly increased intravenous exposure (AUC(last)) of RSV (1 mg/kg) by 73.5%, 62.9% and 53.3% (p < 0.05), respectively than alone group (control). Compared with the control (alone) group, p.o. coadministration of PIP, CA and GA (10 mg/kg) significantly increased the oral exposure (AUC(last)) of RSV (5 mg/kg) by 2.0-fold, 1.83-fold (p < 0.05) and 2.34 -fold (p < 0.05), respectively. Moreover, the cumulative biliary excretion of RSV (5 mg/kg, p.o.) was significantly decreased by 53.3, 33.4 and 39.2% at the end of 8 h after p.o. co-administration of PIP, CA and GA (10 mg/kg), respectively. Taken together, these results indicate that the natural products such as PIP, CA and GA significantly inhibit RSV transport in to bile and increased the plasma exposure (AUC(last)) of RSV.

  3. Gallic acid induces apoptosis in human cervical epithelial cells containing human papillomavirus type 16 episomes.

    PubMed

    Shi, Lin; Lei, Yanjun; Srivastava, Ranjana; Qin, Weihua; Chen, Jason J

    2016-01-01

    The high-risk human papillomaviruses (HPV) that infect the anogenital tract are strongly associated with the development of cervical carcinoma, which is the second most common cancer in women worldwide. Therapeutic drugs specifically targeting HPV are not available. Polyphenolic compounds have gained considerable attention because of their cytotoxic effects against a variety of cancers and certain viruses. In this study, we examined the effects of several polyphenols on cellular proliferation and death of the human cervical cancer cells and human cervical epithelial cells containing stable HPV type 16 episomes (HPVep). Our results show that three polyphenols inhibited proliferation of HeLa cells dose-dependently. Furthermore, one of the examined polyphenols, gallic acid (GA), also inhibited the proliferation of HPVep cells and exhibited significant specificity towards HPV-positive cells. The anti-proliferative effect of GA on HPVep and HeLa cells was associated with apoptosis and upregulation of p53. These results suggest that GA can be a potential candidate for the development of anti-HPV agents.

  4. Coencapsulation of Ferulic and Gallic acid in hp-b-cyclodextrin.

    PubMed

    Olga, Gortzi; Styliani, Christophoridou; Ioannis, Roussis G

    2015-10-15

    The complexes formed by two polyphenols, trans-Ferulic acid (FA) and Gallic acid (GA) with 2-hydroxypropyl-b-cyclodextrin (HPβCD), by the spray-drying method, were studied. Encapsulation-efficiencies (EE) of the complexes prepared were evaluated by HPLC. In the case of co-encapsulation, the EE of GA was lowered, whereas that of FA was almost stable, indicating a possible antagonistic relationship between the two phenols for the HPβCD cavity. The physicochemical characterization of the complexes was carried out by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). SEM observations revealed that the coencapsulated phenolic complex resulted in a more rounded shape outer surfaces of HPβCD than when encapsulated separately. FT-IR and DSC data indicated that the two polyphenols exhibit a possible interaction in the coencapsulated complex. The complexes showed no loss of their ability to scavenge DPPH radical relatively to the single agent at the concentrations used.

  5. Limonium sinense and gallic acid suppress hepatitis C virus infection by blocking early viral entry.

    PubMed

    Hsu, Wen-Chan; Chang, Shun-Pang; Lin, Lie-Chwen; Li, Chia-Lin; Richardson, Christopher D; Lin, Chun-Ching; Lin, Liang-Tzung

    2015-06-01

    A preventive vaccine against hepatitis C virus (HCV) infection remains unavailable and newly developed drugs against viral replication are complicated by potential drug-resistance and high cost. These issues justify the need to develop alternative antiviral agents and expand the scope of strategies for the treatment of hepatitis C, such as targeting viral entry. In this study, we explore the bioactivity of Limonium sinense (L. sinense) and its purified constituents against HCV life cycle using subgenomic replicon and infectious HCV culture systems. Data indicated that the water extract from the underground part of L. sinense (LS-UW) exhibited potent inhibitory activity against HCV at non-cytotoxic concentrations. LS-UW targeted early HCV infection without affecting viral replication, translation, and cell-to-cell transmission, and blocked viral attachment and post-attachment entry/fusion steps. Bioactivity analysis of major constituents from LS-UW through viral infectivity/entry assays revealed that gallic acid (GA) also inhibits HCV entry. Furthermore, both LS-UW and GA could suppress HCV infection of primary human hepatocytes. Due to their potency and ability to target HCV early viral entry, LS-UW and GA may be of value for further development as prospective antivirals against HCV.

  6. Gallic acid suppresses inflammation in dextran sodium sulfate-induced colitis in mice: Possible mechanisms.

    PubMed

    Pandurangan, Ashok Kumar; Mohebali, Nooshin; Esa, Norhaizan Mohd; Looi, Chung Yeng; Ismail, Salmiah; Saadatdoust, Zeinab

    2015-10-01

    Inflammatory bowel diseases (IBD) encompass at least two forms of intestinal inflammation: Crohn's disease and ulcerative colitis (UC). Both conditions are chronic and inflammatory disorders in the gastrointestinal tract, with an increasing prevalence being associated with the industrialization of nations and in developing countries. Patients with these disorders are 10 to 20 times more likely to develop cancer of the colon. The aim of this study was to characterize the effects of a naturally occurring polyphenol, gallic acid (GA), in an experimental murine model of UC. A significant blunting of weight loss and clinical symptoms was observed in dextran sodium sulfate (DSS)-exposed, GA-treated mice compared with control mice. This effect was associated with a remarkable amelioration of the disruption of the colonic architecture, a significant reduction in colonic myeloperoxidase (MPO) activity, and a decrease in the expression of inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and pro-inflammatory cytokines. In addition, GA reduced the activation and nuclear accumulation of p-STAT3(Y705), preventing the degradation of the inhibitory protein IκB and inhibiting of the nuclear translocation of p65-NF-κB in colonic mucosa. These findings suggest that GA exerts potentially clinically useful anti-inflammatory effects mediated through the suppression of p65-NF-κB and IL-6/p-STAT3(Y705) activation.

  7. Identification of KMU-3, a novel derivative of gallic acid, as an inhibitor of adipogenesis.

    PubMed

    Park, Yu-Kyoung; Lee, Jinho; Hong, Victor Sukbong; Choi, Jong-Soon; Lee, Tae-Yoon; Jang, Byeong-Churl

    2014-01-01

    Differentiation of preadipocyte, also called adipogenesis, leads to the phenotype of mature adipocyte. Excessive adipogenesis, however, is largely linked to the development of obesity. Herein we investigated a library of 53 novel chemicals, generated from a number of polyphenolic natural compounds, on adipogenesis. Strikingly, among the chemicals tested, KMU-3, a derivative of gallic acid, strongly suppressed lipid accumulation during the differentiation of 3T3-L1 preadipocytes into adipocytes. On mechanistic levels, KMU-3 inhibited expressions of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), and fatty acid synthase (FAS) during adipocyte differentiation. Moreover, KMU-3 reduced expressions of adipokines, including retinol binding protein-4 (RBP-4), leptin, and regulated on activation, normal T cell expressed and secreted (RANTES) during adipocyte differentiation. Of further note, KMU-3 rapidly blocked the phosphorylation of signal transducer and activator of transcription-3 (STAT-3) during the early stage of adipogenesis. Importantly, pharmacological inhibition studies revealed that AG490, a JAK-2/STAT-3 inhibitor suppressed adipogenesis and STAT-3 phosphorylation, implying that early blockage of STAT-3 activity is crucial for the KMU-3-mediated anti-adipogenesis. These findings demonstrate firstly that KMU-3 inhibits adipogenesis by down-regulating STAT-3, PPAR-γ, C/EBP-α, and FAS. This work shows that KMU-3 is an inhibitor of adipogenesis and thus may have therapeutic potential against obesity.

  8. A comparative study on the degradation of gallic acid by Aspergillus oryzae and Phanerochaete chrysosporium.

    PubMed

    Guo, Danzhao; Zhang, Zhicai; Liu, Dan; Zheng, Huihua; Chen, Hui; Chen, Keping

    2014-01-01

    Recently, as an emerging persistent dissolved organic pollutant (DOP), gallic acid (GA) and its efficient decomposition methods have received global attention. The present work aimed to compare the effect of Aspergillus oryzae 5992 and Phanerochaete chrysosporium 40719 on degradation of different concentrations of GA. The A. oryzae grew well and achieved a GA removal rate up to 99% in media containing 1-4% GA, much higher than P. chrysosporium. The activity of laccase and lignin peroxidase excreted by A. oryzae was higher than that by P. chrysosporium in the presence of GA. Based on the results of high-performance liquid chromatography-electrospray ionization-mass spectrometry, three relevant intermediate metabolites were determined as progallin A, methyl gallate, and pyrogallic acid, implying that A. oryzae could not degrade GA unless the carboxyl in the molecule was protected or removed. In view of the ability of A. oryzae to accommodate a high concentration of GA and achieve a high removal rate, as well as the significantly different enzyme activities involved in GA degradation and the underlying mechanisms between the two fungal strains, A. oryzae is proven to be a superior strain for the degradation of DOP.

  9. Limonium sinense and gallic acid suppress hepatitis C virus infection by blocking early viral entry.

    PubMed

    Hsu, Wen-Chan; Chang, Shun-Pang; Lin, Lie-Chwen; Li, Chia-Lin; Richardson, Christopher D; Lin, Chun-Ching; Lin, Liang-Tzung

    2015-06-01

    A preventive vaccine against hepatitis C virus (HCV) infection remains unavailable and newly developed drugs against viral replication are complicated by potential drug-resistance and high cost. These issues justify the need to develop alternative antiviral agents and expand the scope of strategies for the treatment of hepatitis C, such as targeting viral entry. In this study, we explore the bioactivity of Limonium sinense (L. sinense) and its purified constituents against HCV life cycle using subgenomic replicon and infectious HCV culture systems. Data indicated that the water extract from the underground part of L. sinense (LS-UW) exhibited potent inhibitory activity against HCV at non-cytotoxic concentrations. LS-UW targeted early HCV infection without affecting viral replication, translation, and cell-to-cell transmission, and blocked viral attachment and post-attachment entry/fusion steps. Bioactivity analysis of major constituents from LS-UW through viral infectivity/entry assays revealed that gallic acid (GA) also inhibits HCV entry. Furthermore, both LS-UW and GA could suppress HCV infection of primary human hepatocytes. Due to their potency and ability to target HCV early viral entry, LS-UW and GA may be of value for further development as prospective antivirals against HCV. PMID:25865056

  10. Gallic acid regulates skin photoaging in UVB-exposed fibroblast and hairless mice.

    PubMed

    Hwang, Eunson; Park, Sang-Yong; Lee, Hyun Ji; Lee, Tae Youp; Sun, Zheng-Wang; Yi, Tae Hoo

    2014-12-01

    Ultraviolet (UV) radiation is the primary factor in skin photoaging, which is characterized by wrinkle formation, dryness, and thickening. The mechanisms underlying skin photoaging are closely associated with degradation of collagen via upregulation of matrix metalloproteinase (MMP) activity, which is induced by reactive oxygen species (ROS) production. Gallic acid (GA), a phenolic compound, possesses a variety of biological activities including antioxidant and antiinflammatory activities. We investigated the protective effects of GA against photoaging caused by UVB irradiation using normal human dermal fibroblasts (NHDFs) in vitro and hairless mice in vivo. The production levels of ROS, interlukin-6, and MMP-1 were significantly suppressed, and type I procollagen expression was stimulated in UVB-irradiated and GA-treated NHDFs. GA treatment inhibited the activity of transcription factor activation protein 1. The effects of GA following topical application and dietary administration were examined by measuring wrinkle formation, histological modification, protein expression, and physiological changes such as stratum corneum hydration, transepidermal water loss, and erythema index. We found that GA decreased dryness, skin thickness, and wrinkle formation via negative modulation of MMP-1 secretion and positive regulation of elastin, type I procollagen, and transforming growth factor-β1. Our data indicate that GA is a potential candidate for the prevention of UVB-induced premature skin aging.

  11. Antiviral Effects of Black Raspberry (Rubus coreanus) Seed and Its Gallic Acid against Influenza Virus Infection.

    PubMed

    Lee, Ji-Hye; Oh, Mi; Seok, Jong Hyeon; Kim, Sella; Lee, Dan Bi; Bae, Garam; Bae, Hae-In; Bae, Seon Young; Hong, Young-Min; Kwon, Sang-Oh; Lee, Dong-Hun; Song, Chang-Seon; Mun, Ji Young; Chung, Mi Sook; Kim, Kyung Hyun

    2016-01-01

    Influenza is a serious public health concern worldwide, as it causes significant morbidity and mortality. The emergence of drug-resistant viral strains requires new approaches for the treatment of influenza. In this study, Rubus coreanus seed (RCS) that is left over from the production of wine or juice was found to show antiviral activities against influenza type A and B viruses. Using the time-of-addition plaque assay, viral replication was almost completely abolished by simultaneous treatment with the RCS fraction of less than a 1-kDa molecular weight (RCSF1). One of the polyphenols derived from RCSF1, gallic acid (GA), identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against both influenza type A and B viruses, albeit at relatively high concentrations. RCSF1 was bound to hemagglutinin protein, inhibited hemagglutination significantly and disrupted viral particles, whereas GA was found to only disrupt the viral particles by using transmission electron microscopy. In BALB/c mice infected with influenza virus, oral administration of RCSF1 significantly improved the survival rate and reduced the viral titers in the lungs. Our results demonstrate that RCSF1 and GA show potent and broad antiviral activity against influenza A and B type viruses and are promising sources of agents that target virus particles. PMID:27275830

  12. Gallic acid conjugated with gold nanoparticles: antibacterial activity and mechanism of action on foodborne pathogens.

    PubMed

    Rattanata, Narintorn; Klaynongsruang, Sompong; Leelayuwat, Chanvit; Limpaiboon, Temduang; Lulitanond, Aroonlug; Boonsiri, Patcharee; Chio-Srichan, Sirinart; Soontaranon, Siriwat; Rugmai, Supagorn; Daduang, Jureerut

    2016-01-01

    Foodborne pathogens, including Plesiomonas shigelloides and Shigella flexneri B, are the major cause of diarrheal endemics worldwide. Antibiotic drug resistance is increasing. Therefore, bioactive compounds with antibacterial activity, such as gallic acid (GA), are needed. Gold nanoparticles (AuNPs) are used as drug delivery agents. This study aimed to conjugate and characterize AuNP-GA and to evaluate the antibacterial activity. AuNP was conjugated with GA, and the core-shell structures were characterized by small-angle X-ray scattering and transmission electron microscopy. Antibacterial activity of AuNP-GA against P. shigelloides and S. flexneri B was evaluated by well diffusion method. AuNP-GA bactericidal mechanism was elucidated by Fourier transform infrared microspectroscopic analysis. The results of small-angle X-ray scattering showed that AuNP-GA conjugation was successful. Antibacterial activity of GA against both bacteria was improved by conjugation with AuNP because the minimum inhibitory concentration value of AuNP-GA was significantly decreased (P<0.0001) compared to that of GA. Fourier transform infrared analysis revealed that AuNP-GA resulted in alterations of lipids, proteins, and nucleic acids at the bacterial cell membrane. Our findings show that AuNP-GA has potential for further application in biomedical sciences. PMID:27555764

  13. Release Kinetic in Yogurt from Gallic Acid Microparticles with Chemically Modified Inulin.

    PubMed

    García, Paula; Vergara, Cristina; Robert, Paz

    2015-10-01

    Gallic acid (GA) was encapsulated with native (NIn), cross-linked (CIn) and acetylated (AIn) inulin by spray-drying. Inulin microparticles were characterized by encapsulation efficiency (EE) and their release profile in yogurt. The EE was significantly higher for GA-CIn (98%) compared with GA-NIn (81%) and GA-AIn (77%) microparticles, showing the effect of the modification of inulin on interaction of GA-polymer. GA release profile data in yogurt for GA-CIn, GA-NIn and GA-AIn were fitted to Peppas and Higuchi models in order to obtain the GA release rate constant. Although the GA release rate constants were significantly different among systems, these differences were slight and the GA release was fast (80% < 2 h) in the three systems, showing that inulin-systems did not control GA release in yogurt. The mechanism of GA release followed a Fickian diffusion and relaxation of chains for all microparticles. According to the release profile, these microparticles would be best suited for use in instant foods. PMID:26305430

  14. Release Kinetic in Yogurt from Gallic Acid Microparticles with Chemically Modified Inulin.

    PubMed

    García, Paula; Vergara, Cristina; Robert, Paz

    2015-10-01

    Gallic acid (GA) was encapsulated with native (NIn), cross-linked (CIn) and acetylated (AIn) inulin by spray-drying. Inulin microparticles were characterized by encapsulation efficiency (EE) and their release profile in yogurt. The EE was significantly higher for GA-CIn (98%) compared with GA-NIn (81%) and GA-AIn (77%) microparticles, showing the effect of the modification of inulin on interaction of GA-polymer. GA release profile data in yogurt for GA-CIn, GA-NIn and GA-AIn were fitted to Peppas and Higuchi models in order to obtain the GA release rate constant. Although the GA release rate constants were significantly different among systems, these differences were slight and the GA release was fast (80% < 2 h) in the three systems, showing that inulin-systems did not control GA release in yogurt. The mechanism of GA release followed a Fickian diffusion and relaxation of chains for all microparticles. According to the release profile, these microparticles would be best suited for use in instant foods.

  15. Gallic acid attenuates dextran sulfate sodium-induced experimental colitis in BALB/c mice

    PubMed Central

    Pandurangan, Ashok Kumar; Mohebali, Nooshin; Norhaizan, Mohd Esa; Looi, Chung Yeng

    2015-01-01

    Gallic acid (GA) is a polyhydroxy phenolic compound that has been detected in various natural products, such as green tea, strawberries, grapes, bananas, and many other fruits. In inflammatory bowel disease, inflammation is promoted by oxidative stress. GA is a strong antioxidant; thus, we evaluated the cytoprotective and anti-inflammatory role of GA in a dextran sulfate sodium (DSS)-induced mouse colitis model. Experimental acute colitis was induced in male BALB/c mice by administering 2.5% DSS in the drinking water for 7 days. The disease activity index; colon weight/length ratio; histopathological analysis; mRNA expressions of IL-21 and IL-23; and protein expression of nuclear erythroid 2-related factor 2 (Nrf2) were compared between the control and experimental mice. The colonic content of malondialdehyde and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activity were examined as parameters of the redox state. We determined that GA significantly attenuated the disease activity index and colon shortening, and reduced the histopathological evidence of injury. GA also significantly (P<0.05) reduced the expressions of IL-21 and IL-23. Furthermore, GA activates/upregulates the expression of Nrf2 and its downstream targets, including UDP-GT and NQO1, in DSS-induced mice. The findings of this study demonstrate the protective effect of GA on experimental colitis, which is probably due to an antioxidant nature of GA. PMID:26251571

  16. Structural characterization of lyotropic liquid crystals containing a dendrimer for solubilization and release of gallic acid.

    PubMed

    Bitan-Cherbakovsky, Liron; Aserin, Abraham; Garti, Nissim

    2013-12-01

    The role of 2nd generation polypropyleneimine (PPIG2) dendrimer in controlling the release of gallic acid (GA) as a model drug from lyotropic liquid crystal was explored. GA (0.2wt%) was solubilized in three types of mesophases: lamellar (Lα), cubic (space group of Ia3d, Q(G)), and reverse hexagonal (HII), composed of GMO and water (and d-α-tocopherol, or tricaprylin in the case of HII mesophases). Small angle X-ray scattering (SAXS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) along with UV spectrophotometry were utilized to elucidate the structure modifications and release resulting from the cosolubilization of GA and PPIG2. Solubilization of PPIG2 into Lα and Q(G) phases caused transformation of both structures to HII. The diffusion of GA out of the mesophases was found to be dependent on water content and PPIG2 concentration. Rapid release from Lα+PPIG2 and Q(G)+PPIG2 mesophases was recorded. The release from both HII mixtures (with d-α-tocopherol and tricaprylin) was shown to be dependent on the type of oil. Release studies conducted for 72h showed that GA release can be modulated and sustained by the presence of PPIG2, supposedly due to the electrostatic interactions between the dendrimer and the drug molecule.

  17. Polyplanar optical display electronics

    SciTech Connect

    DeSanto, L.; Biscardi, C.

    1997-07-01

    The Polyplanar Optical Display (POD) is a unique display screen which can be used with any projection source. The prototype ten inch display is two inches thick and has a matte black face which allows for high contrast images. The prototype being developed is a form, fit and functional replacement display for the B-52 aircraft which uses a monochrome ten-inch display. In order to achieve a long lifetime, the new display uses a 100 milliwatt green solid-state laser (10,000 hr. life) at 532 nm as its light source. To produce real-time video, the laser light is being modulated by a Digital Light Processing (DLP{trademark}) chip manufactured by Texas Instruments. In order to use the solid-state laser as the light source and also fit within the constraints of the B-52 display, the Digital Micromirror Device (DMD{trademark}) circuit board is removed from the Texas Instruments DLP light engine assembly. Due to the compact architecture of the projection system within the display chassis, the DMD{trademark} chip is operated remotely from the Texas Instruments circuit board. The authors discuss the operation of the DMD{trademark} divorced from the light engine and the interfacing of the DMD{trademark} board with various video formats (CVBS, Y/C or S-video and RGB) including the format specific to the B-52 aircraft. A brief discussion of the electronics required to drive the laser is also presented.

  18. Display and Presentation Boards.

    ERIC Educational Resources Information Center

    Midgley, Thomas Keith

    The use of display and presentation boards as tools to help teachers/trainers convey messages more clearly is briefly discussed, and 24 different types of display and presentation boards are described and illustrated; i.e., chalk, paste-up, hook-n-loop, electric, flannel, scroll, communication planning, acetate pocket, slot, pin-tack, preview,…

  19. Split image optical display

    DOEpatents

    Veligdan, James T.

    2007-05-29

    A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

  20. Split image optical display

    DOEpatents

    Veligdan, James T.

    2005-05-31

    A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

  1. Effective Monitor Display Design.

    ERIC Educational Resources Information Center

    Harrell, William

    1999-01-01

    Describes some of the factors that affect computer monitor display design and provides suggestions and insights into how screen displays can be designed more effectively. Topics include color, font choices, organizational structure of text, space outline, and general principles. (Author/LRW)

  2. Displaying Images Of Planets

    NASA Technical Reports Server (NTRS)

    Martin, Michael D.; Evans, Frank; Nakamura, Daniel I.

    1991-01-01

    Interactive Image Display Program (IMDISP) is interactive image-displaying utility program for IBM personal computer (PC, XT, and AT models) and compatibles. Magnifications, contrasts, and/or subsampling selected for whole or partial images. IMDISP developed for use with CD-ROM (Compact Disk Read-Only Memory) storage system. Written in C language (94 percent) and Assembler (6 percent).

  3. Displays enabling mobile multimedia

    NASA Astrophysics Data System (ADS)

    Kimmel, Jyrki

    2007-02-01

    With the rapid advances in telecommunications networks, mobile multimedia delivery to handsets is now a reality. While a truly immersive multimedia experience is still far ahead in the mobile world, significant advances have been made in the constituent audio-visual technologies to make this become possible. One of the critical components in multimedia delivery is the mobile handset display. While such alternatives as headset-style near-to-eye displays, autostereoscopic displays, mini-projectors, and roll-out flexible displays can deliver either a larger virtual screen size than the pocketable dimensions of the mobile device can offer, or an added degree of immersion by adding the illusion of the third dimension in the viewing experience, there are still challenges in the full deployment of such displays in real-life mobile communication terminals. Meanwhile, direct-view display technologies have developed steadily, and can provide a development platform for an even better viewing experience for multimedia in the near future. The paper presents an overview of the mobile display technology space with an emphasis on the advances and potential in developing direct-view displays further to meet the goal of enabling multimedia in the mobile domain.

  4. System status display evaluation

    NASA Technical Reports Server (NTRS)

    Summers, Leland G.

    1988-01-01

    The System Status Display is an electronic display system which provides the crew with an enhanced capability for monitoring and managing the aircraft systems. A flight simulation in a fixed base cockpit simulator was used to evaluate alternative design concepts for this display system. The alternative concepts included pictorial versus alphanumeric text formats, multifunction versus dedicated controls, and integration of the procedures with the system status information versus paper checklists. Twelve pilots manually flew approach patterns with the different concepts. System malfunctions occurred which required the pilots to respond to the alert by reconfiguring the system. The pictorial display, the multifunction control interfaces collocated with the system display, and the procedures integrated with the status information all had shorter event processing times and lower subjective workloads.

  5. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode

    PubMed Central

    Newair, Emad F

    2016-01-01

    Summary A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10−6 to 3.38 × 10−5 M with a detection limit of 3.22 × 10−6 M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin–Ciocalteu spectrophotometric results. PMID:27547628

  6. Spectroscopic study of Mg(II) ion influence on the autoxidation of gallic acid in weakly alkaline aqueous solutions

    NASA Astrophysics Data System (ADS)

    Nikolić, G. M.; Veselinović, A. M.; Nikolić, R. S.; Mitić, S. S.

    2011-12-01

    Gallic acid autoxidation in weakly alkaline aqueous solutions was studied by UV-Vis spectrophotometry and ESR spectroscopy under various conditions. Lowering the pH value from 10 to 8.5 probably changes the mechanism of the autoxidation reaction as evidenced by the different time variations of UV-Vis spectra of solutions. The presence of Mg(II) ions greatly influences the autoxidation reaction at pH 8.5. Although the UV-Vis spectral changes with time follow the similar pattern during the gallic acid autoxidation at pH 10 and at pH 8.5 in the presence of Mg(II) ions, some small differences indicate that Mg(II) ions not only affect the electron density of absorbing species but also influence the overall mechanism of the autoxidation reaction. ESR spectra of free radials formed during the initial stage of gallic acid autoxidation at pH 8.5 in the presence of Mg(II) ions were recorded. Computer simulation of ESR spectra allows partial characterization of these free radicals.

  7. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode.

    PubMed

    Abdel-Hamid, Refat; Newair, Emad F

    2016-01-01

    A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10(-6) to 3.38 × 10(-5) M with a detection limit of 3.22 × 10(-6) M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin-Ciocalteu spectrophotometric results.

  8. Gallic Acid Production with Mouldy Polyurethane Particles Obtained from Solid State Culture of Aspergillus niger GH1.

    PubMed

    Mata-Gómez, Marco; Mussatto, Solange I; Rodríguez, Raul; Teixeira, Jose A; Martinez, Jose L; Hernandez, Ayerim; Aguilar, Cristóbal N

    2015-06-01

    Gallic acid production in a batch bioreactor was evaluated using as catalytic material the mouldy polyurethane solids (MPS) obtained from a solid-state fermentation (SSF) bioprocess carried out for tannase production by Aspergillus niger GH1 on polyurethane foam powder (PUF) with 5 % (v/w) of tannic acid as inducer. Fungal biomass, tannic acid consumption and tannase production were kinetically monitored. SSF was stopped when tannase activity reached its maximum level. Effects of washing with distilled water and drying on the tannase activity of MPS were determined. Better results were obtained with dried and washed MPS retaining 84 % of the tannase activity. Maximum tannase activity produced through SSF after 24 h of incubation was equivalent to 130 U/gS with a specific activity of 36 U/mg. The methylgallate was hydrolysed (45 %) in an easy, cheap and fast bioprocess (30 min). Kinetic parameters of tannase self-immobilized on polyurethane particles were calculated to be 5 mM and 04.1 × 10(-2) mM/min for K M and V max, respectively. Results demonstrated that the MPS, with tannase activity, can be successfully used for the production of the antioxidant gallic acid from methyl-gallate substrate. Direct use of PMS to produce gallic acid can be advantageous as no previous extraction of enzyme is required, thus reducing production costs.

  9. Voltammetric determination of polyphenolic content in pomegranate juice using a poly(gallic acid)/multiwalled carbon nanotube modified electrode.

    PubMed

    Abdel-Hamid, Refat; Newair, Emad F

    2016-01-01

    A simple and sensitive poly(gallic acid)/multiwalled carbon nanotube modified glassy carbon electrode (PGA/MWCNT/GCE) electrochemical sensor was prepared for direct determination of the total phenolic content (TPC) as gallic acid equivalent. The GCE working electrode was electrochemically modified and characterized using scanning electron microscope (SEM), cyclic voltammetry (CV), chronoamperometry and chronocoulometry. It was found that gallic acid (GA) exhibits a superior electrochemical response on the PGA/MWCNT/GCE sensor in comparison with bare GCE. The results reveal that a PGA/MWCNT/GCE sensor can remarkably enhance the electro-oxidation signal of GA as well as shift the peak potentials towards less positive potential values. The dependence of peak current on accumulation potential, accumulation time and pH were investigated by square-wave voltammetry (SWV) to optimize the experimental conditions for the determination of GA. Using the optimized conditions, the sensor responded linearly to a GA concentration throughout the range of 4.97 × 10(-6) to 3.38 × 10(-5) M with a detection limit of 3.22 × 10(-6) M (S/N = 3). The fabricated sensor shows good selectivity, stability, repeatability and (101%) recovery. The sensor was successfully utilized for the determination of total phenolic content in fresh pomegranate juice without interference of ascorbic acid, fructose, potassium nitrate and barbituric acid. The obtained data were compared with the standard Folin-Ciocalteu spectrophotometric results. PMID:27547628

  10. Enantiospecific Alkynylation of Alkylboronic Esters

    PubMed Central

    Wang, Yahui; Noble, Adam; Myers, Eddie L.

    2016-01-01

    Abstract Enantioenriched secondary and tertiary alkyl pinacolboronic esters undergo enantiospecific deborylative alkynylation through a Zweifel‐type alkenylation followed by a 1,2‐elimination reaction. The process involves use of α‐lithio vinyl bromide or vinyl carbamate species, for which application to Zweifel‐type reactions has not previously been explored. The resulting functionalized 1,1‐disubstituted alkenes undergo facile base‐mediated elimination to generate terminal alkyne products in high yield and excellent levels of enantiospecificity over a wide range of pinacolboronic ester substrates. Furthermore, along with terminal alkynes, internal and silyl‐protected alkynes can be formed by simply introducing a suitable carbon‐ or silicon‐based electrophile after the base‐mediated 1,2‐elimination reaction. PMID:26934427

  11. Defense display market assessment

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    1998-09-01

    This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD 'office' applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system (NVIS) compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD market for direct-view and large-area military displays is presently estimated to be in excess of 242,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within Service weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern display technologies being developed for civil- commercial markets.

  12. Methods of making alkyl esters

    SciTech Connect

    Elliott, Brian

    2010-08-03

    A method comprising contacting an alcohol, a feed comprising one or more glycerides and equal to or greater than 2 wt % of one or more free fatty acids, and a solid acid catalyst, a nanostructured polymer catalyst, or a sulfated zirconia catalyst in one or more reactors, and recovering from the one or more reactors an effluent comprising equal to or greater than about 75 wt % alkyl ester and equal to or less than about 5 wt % glyceride.

  13. Synthesis, structure, antitumor activity of novel pharmaceutical co-crystals based on bispyridyl-substituted α, β-unsaturated ketones with gallic acid

    NASA Astrophysics Data System (ADS)

    Liu, Lian-Dong; Liu, Shu-Lian; Liu, Zhi-Xian; Hou, Gui-Ge

    2016-05-01

    Three novel pharmaceutical co-crystals, (A)·(gallic acid) (1), (B)·(gallic acid) (2), and (C)·(gallic acid) (3) were generated based on 2,6-bis((pyridin-4-yl)methylene)cyclohexanone (A), N-methyl-3,5-bis((pyridin-3-yl)methylene)-4-piperidone (B), N-methyl-3,5-bis((pyridin-4-yl)methylene)-4-piperidone (C) with gallic acid, respectively. They are characterized by elemental analysis, FTIR spectroscopy, 1H NMR and single-crystal X-ray diffraction. Structural analysis reveals that two pharmaceutical ingredients link each other into H-bonding-driven 3D network in 1, 2, or 2D plane in 3. In addition, their antitumor activities against human neoplastic cell lines A549, SGC-7901, MCF-7, OVCA-433, HePG2 and cytotoxicity for HUVEC cell lines by CCK-8 method were evaluated primarily. Compared with gallic acid and free A, B and C, their antitumor activities have improved distinctly, while cytotoxicities have reduced markedly, especially for co-crystal 1. This is mainly because of the synergistic effect between pharmaceutical ingredients A, B, and C and gallic acid.

  14. Gallic Acid Induces a Reactive Oxygen Species-Provoked c-Jun NH2-Terminal Kinase-Dependent Apoptosis in Lung Fibroblasts

    PubMed Central

    Chen, Chiu-Yuan; Chen, Kun-Chieh; Yang, Tsung-Ying; Liu, Hsiang-Chun; Hsu, Shih-Lan

    2013-01-01

    Idiopathic pulmonary fibrosis is a chronic lung disorder characterized by fibroblasts proliferation and extracellular matrix accumulation. Induction of fibroblast apoptosis therefore plays a crucial role in the resolution of this disease. Gallic acid (3,4,5-trihydroxybenzoic acid), a common botanic phenolic compound, has been reported to induce apoptosis in tumor cell lines and renal fibroblasts. The present study was undertaken to examine the role of mitogen-activated protein kinases (MAPKs) in lung fibroblasts apoptosis induced by gallic acid. We found that treatment with gallic acid resulted in activation of c-Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and protein kinase B (PKB, Akt), but not p38MAPK, in mouse lung fibroblasts. Inhibition of JNK using pharmacologic inhibitor (SP600125) and genetic knockdown (JNK specific siRNA) significantly inhibited p53 accumulation, reduced PUMA and Fas expression, and abolished apoptosis induced by gallic acid. Moreover, treatment with antioxidants (vitamin C, N-acetyl cysteine, and catalase) effectively diminished gallic acid-induced hydrogen peroxide production, JNK and p53 activation, and cell death. These observations imply that gallic acid-mediated hydrogen peroxide formation acts as an initiator of JNK signaling pathways, leading to p53 activation and apoptosis in mouse lung fibroblasts. PMID:23533505

  15. The bioactive compounds alpha-chaconine and gallic acid in potato extracts decrease survival and induce apoptosis in LNCaP and PC3 prostate cancer cells.

    PubMed

    Reddivari, Lavanya; Vanamala, Jairam; Safe, Stephen H; Miller, J Creighton

    2010-01-01

    We recently reported that colored potato extracts and an anthocyanin rich fraction suppressed lymph-node carcinoma of the prostate (LNCaP) and prostate cancer-3 (PC-3) prostate cancer cell proliferation and induced apoptosis via caspase-dependent and caspase-independent pathways. Chlorogenic acid, caffeic acid, gallic acid, catechin, malvidin, and glycoalkaloids (alpha-chaconine and solanine) have now been identified as the major bioactive components of potato, and their effects on LNCaP and PC-3 cell proliferation and apoptosis have been investigated. alpha-chaconine (5 microg/ml) and gallic acid (15 microg/ml) exhibited potent antiproliferative properties and increased cyclin-dependent kinase inhibitor p27 levels in both cell lines. Both alpha-chaconine and gallic acid induced poly [adenosine diphosphate (ADP)] ribose polymerase cleavage and caspase-dependent apoptosis in LNCaP cells; however, caspase-independent apoptosis through nuclear translocation of endonuclease G was observed in both LNCaP and PC-3 cells. alpha-chaconine and gallic acid activated c-Jun N-terminal protein kinase (JNK), and this response played a major role in induction of caspase-dependent apoptosis in LNCaP cells; whereas modulation of JNK and mitogen-activated protein kinase did not affect alpha-chaconine- and gallic acid-induced caspase-independent apoptosis. These results suggest that apoptosis induced by whole potato extracts in prostate cancer cell lines may be in part due to alpha-chaconine and gallic acid.

  16. Effects of different steeping methods and storage on caffeine, catechins and gallic acid in bag tea infusions.

    PubMed

    Yang, Deng-Jye; Hwang, Lucy Sun; Lin, Jau-Tien

    2007-07-13

    Bag teas, packed 3g of ground black, green, oolong, paochoung and pu-erh tea leaves (the particle size used was 1-2mm), were steeped in 150 mL of 70, 85 or 100 degrees C hot water to study the effects of the number of steeping (the same bag tea was steeped repeatedly eight times, 30s each time, as done in China for making ceremonial tea) and varied steeping durations (0.5-4 min) on caffeine, catechins and gallic acid in tea infusions. The changes in tea infusions during storage at 4 or 25 degrees C for 0-48 h and the variations in these compounds of bag tea infused with 150 mL of 4 or 25 degrees C cold water for 0.5-16 h were also investigated. A HPLC method with a C18 column and a step gradient solvent system consisting of acetonitrile and 0.9% acetic acid in deionized water was used for analysis. Results for all kinds of tea samples showed that the second tea infusion contained the highest contents of caffeine, catechins and gallic acid when bag teas were steeped in 70 degrees C water. It was different from that steeped at 85 and 100 degrees C, the highest contents existed in the first infusion. These compounds decreased gradually in later infusions. Higher amounts of caffeine, catechins and gallic acid could be released from bag teas as hotter water was used. As steeping duration prolonged, these ingredients increased progressively, however, their levels were lower than that cumulated from the infusions with the identical bag tea prepared recurrently at the same temperature and time points. (-)-Gallocatechin gallate and (+)-catechin existed in these tea infusions rarely and could not be detected until a certain amount of them infusing. Except gallic acid that showed a significant increase and caffeine that exhibited no significant change, all kinds of catechins decreased appreciably after tea infusions were stored at 25 degrees C for 36 h; nevertheless, all of them showed no evident changes at 4 degrees C storage. The caffeine, catechins and gallic acid in tea

  17. C19 odd-chain polyunsaturated fatty acids (PUfas) are metabolized to C21-PUfas in a rat liver cell line, and curcumin, gallic acid, and their related compounds inhibit their desaturation.

    PubMed

    Nakano, N; Shirasaka, N; Koyama, H; Hino, M; Murakami, T; Shimizu, S; Yoshizumi, H

    2000-08-01

    It was demonstrated that the rat liver cell line BRL-3A converted exogenous C19 odd chain-polyunsaturated fatty acids (PUFAs) into the corresponding C21- and C23-PUFAs as follows: 21:3n-8, 21:4n-8, 23:3n-8, and 23:4n-8 (from 19:3n-8); 21:4n-5, 21:5n-5, 23:4n-5, and 23:5n-5 (from 19:4n-5); 21:5n-2, 21:6n-2, 23:5n-2, and 23:6n-2 (from 19:5n-2). It presumed that these C19 PUFAs were converted through the mimic route to docosahexaenoic acid (22:6n-3) from eicosapentaenoic acid (20:5n-3). In addition, the characterization of the change of fatty acid composition of cellular lipids in rat liver cells were examined, using 19:4n-5 and several fatty acid desaturation inhibitors. Curcumin related compounds, curcumin, capsaicin, isoeugenol, 4-(4-hydroxy-3-methoxyphenyl)-3-buten-2-one, and gallic acid esters with near five carbon numbered alcohol had great changes of fatty acid composition of cellular lipids based on inhibition of the A6 desaturation of C24-PUFAs in rat liver cells.

  18. Cyanate ester based multifunctional nanocomposites for structural capacitors

    NASA Astrophysics Data System (ADS)

    Sun, Weixing

    Two multifunctional cyanate ester based composites with nanofillers of core-shell microstructures were synthesized and investigated for dielectric, mechanical, and other particular properties for the application of multifunctional structural capacitors. The weight reduction and device integration in spacecraft can contribute to significant energy saving by employing multifunctional structural capacitors. Si nanoparticles/Bisphenol E cyanater ester (Si/BECy) nanocomposites show a significant increase in dielectric constant compared to neat BECy. A low dielectric loss tangent is still maintained in this system thanks to the core-shell (Si-SiO2) microstructure of Si particles. Incorporation of Si nanoparticles also results in a large increase in composite's storage modulus. Furthermore, the AC conductivity of the composite was observed to decrease under compressive mechanical stresses due to the piezoresistive effect of Si. Agglomerates of Fe3O4 nanoparticles coated with SiO2 are synthesized and incorporated into BECy to obtain nanocomposites, revealing an enhanced dielectric constant and storage modulus, and a relatively low loss tangent over a wide frequency and temperature range similar to Si/BECy system. Therefore, these novel cyanate ester based nanocomposites simultaneously display mechanical load-carrying, electric energy-storing and other functional properties, promising for multifunctional devices, in this case, structural capacitors.

  19. Gardens on Display.

    ERIC Educational Resources Information Center

    Steinheimer, Margaret

    1998-01-01

    Discusses display gardens and their development by students. Presents guidelines for construction and size consideration and describes details of an outdoor garden, volcanic garden, and shoe box dioramas. (DDR)

  20. Military display performance parameters

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Meyer, Frederick

    2012-06-01

    The military display market is analyzed in terms of four of its segments: avionics, vetronics, dismounted soldier, and command and control. Requirements are summarized for a number of technology-driving parameters, to include luminance, night vision imaging system compatibility, gray levels, resolution, dimming range, viewing angle, video capability, altitude, temperature, shock and vibration, etc., for direct-view and virtual-view displays in cockpits and crew stations. Technical specifications are discussed for selected programs.

  1. Raster graphics display library

    NASA Technical Reports Server (NTRS)

    Grimsrud, Anders; Stephenson, Michael B.

    1987-01-01

    The Raster Graphics Display Library (RGDL) is a high level subroutine package that give the advanced raster graphics display capabilities needed. The RGDL uses FORTRAN source code routines to build subroutines modular enough to use as stand-alone routines in a black box type of environment. Six examples are presented which will teach the use of RGDL in the fastest, most complete way possible. Routines within the display library that are used to produce raster graphics are presented in alphabetical order, each on a separate page. Each user-callable routine is described by function and calling parameters. All common blocks that are used in the display library are listed and the use of each variable within each common block is discussed. A reference on the include files that are necessary to compile the display library is contained. Each include file and its purpose are listed. The link map for MOVIE.BYU version 6, a general purpose computer graphics display system that uses RGDL software, is also contained.

  2. Antimicrobial action of esters of polyhydric alcohols.

    PubMed

    Conley, A J; Kabara, J J

    1973-11-01

    A broth dilution method was used to determine the minimal inhibitory concentration of a series of fatty acid esters of polyhydric alcohols against gram-negative and gram-positive organisms. Gram-negative organisms were not affected. Gram-positive organisms were inhibited as follows. Of the monoglycerol esters, monoglycerol laurate was the most active. Esters of polyglycerols (tri-, hexa-, and decaglycerol esters) were generally active when the fatty acid had chain lengths of 8 to 12 carbon atoms. Sucrose esters, when active, except for laurate, are more active than the free fatty acid. The spectrum of antimicrobial action of esters of polyhydric alcohols is narrower when compared with the free acids. PMID:4791484

  3. Nonaqueous enzymatic synthesis of ester fuels

    SciTech Connect

    Olson, E.S.; Singh, H.K.; Yagelowich, M.L.

    1993-12-31

    The application of nonaqueous enzyme slurries for the production of fatty ester fuels from coal-derived alcohols and triglyceride oils was investigated. Nonaqueous enzyme systems can greatly facilitate many organic reactions, especially those that result in formation of esters and amides. The production of biomass ester fuels from triglyceride oils involves transesterification of the triglyceride with an alcohol. Phenolic tars from coal gasification wastes were fractionated and treated to convert them to an alcohol form, and the intermediate alcohols were converted to the fatty ester in a nonaqueous lipase system. Lipases in a variety of organic solvents were intensively investigated for acylation of coal derivatives containing alcohol functional groups. The two-step process transformed the black poorly soluble phenolics to clean paraffin-soluble esters. Diesel testing demonstrated that the product esters could be substituted for diesel fuels.

  4. Gallic acid functions as a TRPA1 antagonist with relevant antinociceptive and antiedematogenic effects in mice.

    PubMed

    Trevisan, Gabriela; Rossato, Mateus F; Tonello, Raquel; Hoffmeister, Carin; Klafke, Jonatas Z; Rosa, Fernanda; Pinheiro, Kelly V; Pinheiro, Francielle V; Boligon, Aline A; Athayde, Margareth L; Ferreira, Juliano

    2014-07-01

    The transient receptor potential ankyrin 1 (TRPA1) has been identified as a relevant target for the development of novel analgesics. Gallic acid (GA) is a polyphenolic compound commonly found in green tea and various berries and possesses a wide range of biological activities. The goal of this study was to identify GA as a TRPA1 antagonist and observe its antinociceptive effects in different pain models. First, we evaluated the ability of GA to affect cinnamaldehyde-induced calcium influx. Then, we observed the antinociceptive and antiedematogenic effects of GA (3-100 mg/kg) oral administration after the intraplantar (i.pl.) injection of TRPA1 agonists (allyl isothiocyanate, cinnamaldehyde, or hydrogen peroxide-H2O2) in either an inflammatory pain model (carrageenan i.pl. injection) or a neuropathic pain model (chronic constriction injury) in male Swiss mice (25-35 g). GA reduced the calcium influx mediated by TRPA1 activation. Moreover, the oral administration of GA decreased the spontaneous nociception triggered by allyl isothiocyanate, cinnamaldehyde, and H2O2. Carrageenan-induced allodynia and edema were largely reduced by the pretreatment with GA. Moreover, the administration of GA was also capable of decreasing cold and mechanical allodynia in a neuropathic pain model. Finally, GA was absorbed after oral administration and did not produce any detectable side effects. In conclusion, we found that GA is a TRPA1 antagonist with antinociceptive properties in relevant models of clinical pain without detectable side effects, which makes it a good candidate for the treatment of painful conditions.

  5. Selective extraction of gallic acid in pomegranate rind using surface imprinting polymers over magnetic carbon nanotubes.

    PubMed

    Hao, Yi; Gao, Ruixia; Liu, Dechun; Tang, Yuhai; Guo, Zengjun

    2015-10-01

    A novel surface imprinting polymer based on magnetic carbon nanotubes was prepared using dendritic polyethyleneimine as functional monomer to amplify the number of imprinted cavities. The characteristics of resulting polymers were evaluated by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and vibrating sample magnetometer (VSM). Results suggest that magnetic nanoparticles are deposited onto the surface of multiwalled carbon nanotubes and the imprinted shell is coated on the surface of magnetic carbon nanotubes with a thickness of approximately 8 nm. Magnetic imprinted polymers are sensitive to magnetic fields and can be easily separated within 3 s using an external magnet. The adsorption results indicate that the obtained imprinted polymers have fast kinetics, an ultrahigh adsorption capacity of 479.9 mg g(-1), and satisfactory selectivity towards the template molecule. The prepared materials have excellent stability with no obvious deterioration after six adsorption-regeneration cycles. In addition, a method for determination of gallic acid (GA) in pomegranate rind was developed, using a combination of the prepared polymers used as solid-phase extraction (SPE) sorbents and high-performance liquid chromatography (HPLC) for rapid isolation and determination of GA. The limit of detection of the proposed method is 0.001 μg mL(-1), and the intra and inter-day relative standard deviations (RSDs) are lower than 3.8% and 5.3%, respectively. The recoveries of GA from pomegranate rind extract are in the range 98.2-103.6% with RSDs lower than 4.3%.

  6. α-Tocopherol/Gallic Acid Cooperation in the Protection of Galactolipids Against Ozone-Induced Oxidation.

    PubMed

    Rudolphi-Skórska, Elżbieta; Filek, Maria; Zembala, Maria

    2016-04-01

    The protective ability of α-tocopherol (TOH) and gallic acid (GA) acting simultaneously at the moment of oxidizer application was evaluated by determination of galactolipid layers' oxidation degree. Addition of GA resulted in a significant decrease of ozone-derived radicals shifting the threshold of lipid sensitivity by an amount approximately corresponding to the GA intake in bulk reaction with ozone. TOH presence in lipid layers results in a change of the role of GA which additionally may be involved in the reduction of tocopheroxyl radical formed during oxidation. This leads to a decrease in effectiveness of GA in diminishing the amount of ozone radicals. Such an effect was not observed for mixed layers containing galactolipid and pre-oxidized tocopherol where the ozone threshold level was associated with a stoichiometry of GA + O3 reaction. It was concluded that probably subsequent transformations of tocopheroxyl radical to less reactive forms prevent its reaction with GA the entire quantity of which is used for radicals scavenging. This result shows the role of time parameter in systems where substrates are engaged in various reactions taking place simultaneously. The inactivation of 1,1-diphenyl-2-picrylhydrazyl radical by studied antioxidants in homogeneous system confirmed observations made on the basis of lipid layer properties indicating their antagonistic action (at least at studied conditions). Formation of layers in post-oxidation situation did not depend whether tocopherol was oxidized during oxidation of lipid/tocopherol mixture or was introduced as pre-oxidized. This may be interpreted as indication that products of tocopherol oxidation may stabilize lipid layers. PMID:26498297

  7. α-Tocopherol/Gallic Acid Cooperation in the Protection of Galactolipids Against Ozone-Induced Oxidation.

    PubMed

    Rudolphi-Skórska, Elżbieta; Filek, Maria; Zembala, Maria

    2016-04-01

    The protective ability of α-tocopherol (TOH) and gallic acid (GA) acting simultaneously at the moment of oxidizer application was evaluated by determination of galactolipid layers' oxidation degree. Addition of GA resulted in a significant decrease of ozone-derived radicals shifting the threshold of lipid sensitivity by an amount approximately corresponding to the GA intake in bulk reaction with ozone. TOH presence in lipid layers results in a change of the role of GA which additionally may be involved in the reduction of tocopheroxyl radical formed during oxidation. This leads to a decrease in effectiveness of GA in diminishing the amount of ozone radicals. Such an effect was not observed for mixed layers containing galactolipid and pre-oxidized tocopherol where the ozone threshold level was associated with a stoichiometry of GA + O3 reaction. It was concluded that probably subsequent transformations of tocopheroxyl radical to less reactive forms prevent its reaction with GA the entire quantity of which is used for radicals scavenging. This result shows the role of time parameter in systems where substrates are engaged in various reactions taking place simultaneously. The inactivation of 1,1-diphenyl-2-picrylhydrazyl radical by studied antioxidants in homogeneous system confirmed observations made on the basis of lipid layer properties indicating their antagonistic action (at least at studied conditions). Formation of layers in post-oxidation situation did not depend whether tocopherol was oxidized during oxidation of lipid/tocopherol mixture or was introduced as pre-oxidized. This may be interpreted as indication that products of tocopherol oxidation may stabilize lipid layers.

  8. Gallic acid regulates body weight and glucose homeostasis through AMPK activation.

    PubMed

    Doan, Khanh V; Ko, Chang Mann; Kinyua, Ann W; Yang, Dong Joo; Choi, Yun-Hee; Oh, In Young; Nguyen, Nguyen Minh; Ko, Ara; Choi, Jae Won; Jeong, Yangsik; Jung, Min Ho; Cho, Won Gil; Xu, Shanhua; Park, Kyu Sang; Park, Woo Jin; Choi, Soo Yong; Kim, Hyoung Shik; Moh, Sang Hyun; Kim, Ki Woo

    2015-01-01

    Gallic acid [3,4,5-trihydroxybenzoic acid (GA)], a natural phytochemical, is known to have a variety of cellular functions including beneficial effects on metabolic syndromes. However, the molecular mechanism by which GA exerts its beneficial effects is not known. Here we report that GA plays its role through the activation of AMP-activated protein kinase (AMPK) and by regulating mitochondrial function via the activation of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α). Sirtuin 1 (Sirt1) knockdown significantly blunted GA's effect on PGC1α activation and downstream genes, suggesting a critical role of the AMPK/Sirt1/PGC1α pathway in GA's action. Moreover, diet-induced obese mice treated with GA showed significantly improved glucose and insulin homeostasis. In addition, the administration of GA protected diet-induced body weight gain without a change in food intake. Biochemical analyses revealed a marked activation of AMPK in the liver, muscle, and interscapular brown adipose tissue of the GA-treated mice. Moreover, uncoupling protein 1 together with other genes related to energy expenditure was significantly elevated in the interscapular brown adipose tissue. Taken together, these results indicate that GA plays its beneficial metabolic roles by activating the AMPK/Sirt1/PGC1α pathway and by changing the interscapular brown adipose tissue genes related to thermogenesis. Our study points out that targeting the activation of the AMPK/Sirt1/PGC1α pathway by GA or its derivatives might be a potential therapeutic intervention for insulin resistance in metabolic diseases.

  9. Skin penetration and antioxidant effect of cosmeto-textiles with gallic acid.

    PubMed

    Alonso, C; Martí, M; Barba, C; Lis, M; Rubio, L; Coderch, L

    2016-03-01

    In this work, the antioxidant gallic acid (GA) has been encapsulated in microspheres prepared with poly-ε-caprolactone (PCL) and incorporated into polyamide (PA) obtaining the cosmeto-textile. The topical application of the cosmeto-textile provides a reservoir effect in the skin delivery of GA. The close contact of the cosmeto-textile, containing microsphere-encapsulated GA (ME-GA), with the skin and their corresponding occlusion, may be the main reasons that explain the crossing of active principle (GA) through the skin barrier, located in the stratum corneum, and its penetration into the different compartments of the skin, epidermis and dermis. An ex vivo assessment was performed to evaluate the antioxidant effect of the ME-GA on the stratum corneum (SC) using the thiobarbituric acid-reactive species (TBARS) test. The test is based on a non-invasive ex vivo methodology that evaluates lipid peroxides formed in the outermost layers of the SC from human volunteers after UV radiation to determine the effectiveness of an antioxidant. In this case, a ME-GA cosmeto-textile or ME-GA formulation were applied to the skin in vivo and lipid peroxidation (LPO) in the horny layer were determined after UV irradiation. This methodology may be used as a quality control tool to determine ex vivo the percentage of LPO inhibition on human SC for a variety of antioxidants that are topically applied, in this case GA. Results show that LPO formation was inhibited in human SC when GA was applied directly or embedded in the cosmeto-textile, demonstrating the effectiveness of both applications. The percentage of LPO inhibition obtained after both topical applications was approximately 10% for the cosmeto-textile and 41% for the direct application of microspheres containing GA. This methodology could be used to determine the effectiveness of topically applied antioxidants encapsulated in cosmeto-textiles on human SC. PMID:26848532

  10. Gallic Acid Induces Necroptosis via TNF–α Signaling Pathway in Activated Hepatic Stellate Cells

    PubMed Central

    Chang, Ya Ju; Hsu, Shih Lan; Liu, Yi Ting; Lin, Yu Hsuan; Lin, Ming Hui; Huang, Shu Jung; Ho, Ja-an Annie; Wu, Li-Chen

    2015-01-01

    Gallic acid (3, 4, 5-trihydroxybenzoic acid, GA), a natural phenolic acid widely found in gallnuts, tea leaves and various fruits, possesses several bioactivities against inflammation, oxidation, and carcinogenicity. The beneficial effect of GA on the reduction of animal hepatofibrosis has been indicated due to its antioxidative property. However, the cytotoxicity of GA autoxidation causing cell death has also been reported. Herein, we postulated that GA might target activated hepatic stellate cells (aHSCs), the cell type responsible for hepatofibrosis, to mitigate the process of fibrosis. The molecular cytotoxic mechanisms that GA exerted on aHSCs were then analyzed. The results indicated that GA elicited aHSC programmed cell death through TNF–α–mediated necroptosis. GA induced significant oxidative stress through the suppression of catalase activity and the depletion of glutathione (GSH). Elevated oxidative stress triggered the production of TNF–α facilitating the undergoing of necroptosis through the up-regulation of key necroptotic regulatory proteins TRADD and receptor-interacting protein 3 (RIP3), and the inactivation of caspase–8. Calmodulin and calpain–1 activation were engaged, which promoted subsequent lysosomal membrane permeabilization (LMP). The TNF–α antagonist (SPD–304) and the RIP1 inhibitor (necrostatin–1, Nec–1) confirmed GA-induced TNFR1–mediated necroptosis. The inhibition of RIP1 by Nec–1 diverted the cell death from necroptosis to apoptosis, as the activation of caspase 3 and the increase of cytochrome c. Collectively, this is the first report indicating that GA induces TNF signaling–triggered necroptosis in aHSCs, which may offer an alternative strategy for the amelioration of liver fibrosis. PMID:25816210

  11. Skin penetration and antioxidant effect of cosmeto-textiles with gallic acid.

    PubMed

    Alonso, C; Martí, M; Barba, C; Lis, M; Rubio, L; Coderch, L

    2016-03-01

    In this work, the antioxidant gallic acid (GA) has been encapsulated in microspheres prepared with poly-ε-caprolactone (PCL) and incorporated into polyamide (PA) obtaining the cosmeto-textile. The topical application of the cosmeto-textile provides a reservoir effect in the skin delivery of GA. The close contact of the cosmeto-textile, containing microsphere-encapsulated GA (ME-GA), with the skin and their corresponding occlusion, may be the main reasons that explain the crossing of active principle (GA) through the skin barrier, located in the stratum corneum, and its penetration into the different compartments of the skin, epidermis and dermis. An ex vivo assessment was performed to evaluate the antioxidant effect of the ME-GA on the stratum corneum (SC) using the thiobarbituric acid-reactive species (TBARS) test. The test is based on a non-invasive ex vivo methodology that evaluates lipid peroxides formed in the outermost layers of the SC from human volunteers after UV radiation to determine the effectiveness of an antioxidant. In this case, a ME-GA cosmeto-textile or ME-GA formulation were applied to the skin in vivo and lipid peroxidation (LPO) in the horny layer were determined after UV irradiation. This methodology may be used as a quality control tool to determine ex vivo the percentage of LPO inhibition on human SC for a variety of antioxidants that are topically applied, in this case GA. Results show that LPO formation was inhibited in human SC when GA was applied directly or embedded in the cosmeto-textile, demonstrating the effectiveness of both applications. The percentage of LPO inhibition obtained after both topical applications was approximately 10% for the cosmeto-textile and 41% for the direct application of microspheres containing GA. This methodology could be used to determine the effectiveness of topically applied antioxidants encapsulated in cosmeto-textiles on human SC.

  12. Tryptamine-Gallic Acid Hybrid Prevents Non-steroidal Anti-inflammatory Drug-induced Gastropathy

    PubMed Central

    Pal, Chinmay; Bindu, Samik; Dey, Sumanta; Alam, Athar; Goyal, Manish; Iqbal, Mohd. Shameel; Sarkar, Souvik; Kumar, Rahul; Halder, Kamal Krishna; Debnath, Mita Chatterjee; Adhikari, Susanta; Bandyopadhyay, Uday

    2012-01-01

    We have investigated the gastroprotective effect of SEGA (3a), a newly synthesized tryptamine-gallic acid hybrid molecule against non-steroidal anti-inflammatory drug (NSAID)-induced gastropathy with mechanistic details. SEGA (3a) prevents indomethacin (NSAID)-induced mitochondrial oxidative stress (MOS) and dysfunctions in gastric mucosal cells, which play a pathogenic role in inducing gastropathy. SEGA (3a) offers this mitoprotective effect by scavenging of mitochondrial superoxide anion (O2˙̄) and intramitochondrial free iron released as a result of MOS. SEGA (3a) in vivo blocks indomethacin-mediated MOS, as is evident from the inhibition of indomethacin-induced mitochondrial protein carbonyl formation, lipid peroxidation, and thiol depletion. SEGA (3a) corrects indomethacin-mediated mitochondrial dysfunction in vivo by restoring defective electron transport chain function, collapse of transmembrane potential, and loss of dehydrogenase activity. SEGA (3a) not only corrects mitochondrial dysfunction but also inhibits the activation of the mitochondrial pathway of apoptosis by indomethacin. SEGA (3a) inhibits indomethacin-induced down-regulation of bcl-2 and up-regulation of bax genes in gastric mucosa. SEGA (3a) also inhibits indometacin-induced activation of caspase-9 and caspase-3 in gastric mucosa. Besides the gastroprotective effect against NSAID, SEGA (3a) also expedites the healing of already damaged gastric mucosa. Radiolabeled (99mTc-labeled SEGA (3a)) tracer studies confirm that SEGA (3a) enters into mitochondria of gastric mucosal cell in vivo, and it is quite stable in serum. Thus, SEGA (3a) bears an immense potential to be a novel gastroprotective agent against NSAID-induced gastropathy. PMID:22157011

  13. Gallic acid decreases hepatitis C virus expression through its antioxidant capacity

    PubMed Central

    GOVEA-SALAS, MAYELA; RIVAS-ESTILLA, ANA MARIA; RODRÍGUEZ-HERRERA, RAUL; LOZANO-SEPÚLVEDA, SONIA A.; AGUILAR-GONZALEZ, CRISTOBAL N.; ZUGASTI-CRUZ, ALEJANDRO; SALAS-VILLALOBOS, TANYA B.; MORLETT-CHÁVEZ, JESUS ANTONIO

    2016-01-01

    Gallic acid (GA) is a natural phenolic compound that possesses various biological effects, including antioxidant, anti-inflammatory, antibiotic, anticancer, antiviral and cardiovascular protection activities. In addition, numerous studies have reported that antioxidants possess antiviral activities. Hepatitis C virus (HCV) is one of the most important causes of chronic liver diseases worldwide, but until recently, only a small number of antiviral agents had been developed against HCV. Therefore, the present study investigated whether GA exhibits an anti-HCV activity. The effects of GA on HCV expression were examined using a subgenomic HCV replicon cell culture system that expressed HCV nonstructural proteins (NSs). In addition, GA cytotoxicity was evaluated at concentrations between 100–600 mg/ml using an MTT assay. Huh-7 replicon cells were incubated with 300 mg/ml GA for different times, and the HCV-RNA and protein levels were measured by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. Pyrrolidine dithiocarbamate (PDTC) was used as an antioxidant control and reactive oxygen species (ROS) production was measured during the exposure. The results indicated that GA did not produce a statistically significant cytotoxicity in parental and HCV replicon cells. Furthermore, GA downregulated the expression levels of NS5A-HCV protein (~55%) and HCV-RNA (~50%) in a time-dependent manner compared with the levels in untreated cells. Notably, GA treatment decreased ROS production at the early time points of exposure in cells expressing HCV proteins. Similar results were obtained upon PDTC exposure. These findings suggest that the antioxidant capacity of GA may be involved in the downregulation of HCV replication in hepatoma cells. PMID:26893656

  14. Green synthesis and characterization of Au@Pt core-shell bimetallic nanoparticles using gallic acid

    NASA Astrophysics Data System (ADS)

    Zhang, Guojun; Zheng, Hongmei; Shen, Ming; Wang, Lei; Wang, Xiaosan

    2015-06-01

    In this study, we developed a facile and benign green synthesis approach for the successful fabrication of well-dispersed urchin-like Au@Pt core-shell nanoparticles (NPs) using gallic acid (GA) as both a reducing and protecting agent. The proposed one-step synthesis exploits the differences in the reduction potentials of AuCl4- and PtCl62-, where the AuCl4- ions are preferentially reduced to Au cores and the PtCl62- ions are then deposited continuously onto the Au core surface as a Pt shell. The as-prepared Au@Pt NPs were characterized by transmission electron microscope (TEM); high-resolution transmission electron microscope (HR-TEM); scanning electron microscope (SEM); UV-vis absorption spectra (UV-vis); X-ray diffraction (XRD); Fourier transmission infrared spectra (FT-IR). We systematically investigated the effects of some experimental parameters on the formation of the Au@Pt NPs, i.e., the reaction temperature, the molar ratios of HAuCl4/H2PtCl6, and the amount of GA. When polyvinylpyrrolidone K-30 (PVP) was used as a protecting agent, the Au@Pt core-shell NPs obtained using this green synthesis method were better dispersed and smaller in size. The as-prepared Au@Pt NPs exhibited better catalytic activity in the reaction where NaBH4 reduced p-nitrophenol to p-aminophenol. However, the results showed that the Au@Pt bimetallic NPs had a lower catalytic activity than the pure Au NPs obtained by the same method, which confirmed the formation of Au@Pt core-shell nanostructures because the active sites on the surfaces of the Au NPs were covered with a Pt shell.

  15. Other factors to consider in the formation of chloropropandiol fatty esters in oil processes.

    PubMed

    Ramli, Muhamad Roddy; Siew, Wai Lin; Ibrahim, Nuzul Amri; Kuntom, Ainie; Abd Razak, Raznim Arni

    2015-01-01

    This paper examines the processing steps of extracting palm oil from fresh fruit bunches in a way that may impact on the formation of chloropropandiol fatty esters (3-MCPD esters), particularly during refining. Diacylglycerols (DAGs) do not appear to be a critical factor when crude palm oils are extracted from various qualities of fruit bunches. Highly hydrolysed oils, in spite of the high free fatty acid (FFA) contents, did not show exceptionally high DAGs, and the oils did not display a higher formation of 3-MCPD esters upon heat treatment. However, acidity measured in terms of pH appears to have a strong impact on 3-MCPD ester formation in the crude oil when heated at high temperatures. The differences in the extraction process of crude palm oil from current commercial processes and that from a modified experimental process showed clearly the effect of acidity of the oil on the formation of 3-MCPD esters. This paper concludes that the washing or dilution step in palm oil mills removes the acidity of the vegetative materials and that a well-optimised dilution/washing step in the extraction process will play an important role in reducing formation of 3-MCPD esters in crude palm oil upon further heat processing.

  16. Other factors to consider in the formation of chloropropandiol fatty esters in oil processes.

    PubMed

    Ramli, Muhamad Roddy; Siew, Wai Lin; Ibrahim, Nuzul Amri; Kuntom, Ainie; Abd Razak, Raznim Arni

    2015-01-01

    This paper examines the processing steps of extracting palm oil from fresh fruit bunches in a way that may impact on the formation of chloropropandiol fatty esters (3-MCPD esters), particularly during refining. Diacylglycerols (DAGs) do not appear to be a critical factor when crude palm oils are extracted from various qualities of fruit bunches. Highly hydrolysed oils, in spite of the high free fatty acid (FFA) contents, did not show exceptionally high DAGs, and the oils did not display a higher formation of 3-MCPD esters upon heat treatment. However, acidity measured in terms of pH appears to have a strong impact on 3-MCPD ester formation in the crude oil when heated at high temperatures. The differences in the extraction process of crude palm oil from current commercial processes and that from a modified experimental process showed clearly the effect of acidity of the oil on the formation of 3-MCPD esters. This paper concludes that the washing or dilution step in palm oil mills removes the acidity of the vegetative materials and that a well-optimised dilution/washing step in the extraction process will play an important role in reducing formation of 3-MCPD esters in crude palm oil upon further heat processing. PMID:25798697

  17. Method of making a cyanate ester foam

    SciTech Connect

    Celina, Mathias C.; Giron, Nicholas Henry

    2014-08-05

    A cyanate ester resin mixture with at least one cyanate ester resin, an isocyanate foaming resin, other co-curatives such as polyol or epoxy compounds, a surfactant, and a catalyst/water can react to form a foaming resin that can be cured at a temperature greater than 50.degree. C. to form a cyanate ester foam. The cyanate ester foam can be heated to a temperature greater than 400.degree. C. in a non-oxidative atmosphere to provide a carbonaceous char foam.

  18. Chemoselective Boronic Ester Synthesis by Controlled Speciation**

    PubMed Central

    Fyfe, James W B; Seath, Ciaran P; Watson, Allan J B

    2014-01-01

    Control of boronic acid solution speciation is presented as a new strategy for the chemoselective synthesis of boronic esters. Manipulation of the solution equilibria within a cross-coupling milieu enables the formal homologation of aryl and alkenyl boronic acid pinacol esters. The generation of a new, reactive boronic ester in the presence of an active palladium catalyst also facilitates streamlined iterative catalytic C=C bond formation and provides a method for the controlled oligomerization of sp2-hybridized boronic esters. PMID:25267096

  19. Steroidal esters from Ferula sinkiangensis.

    PubMed

    Li, Guangzhi; Li, Xiaojin; Cao, Li; Shen, Liangang; Zhu, Jun; Zhang, Jing; Wang, Junchi; Zhang, Lijing; Si, Jianyong

    2014-09-01

    Two new steroidal esters with an unusual framework, Sinkiangenorin A and B, a new organic acid glycoside, Sinkiangenorin C, and four known lignin compounds were isolated from the seeds of Ferula sinkiangensis. The structures of these compounds were established by spectroscopic analysis and single-crystal X-ray diffraction. All of the isolated compounds were tested against Hela, K562 and AGS human cancer cell lines. Sinkiangenorin C showed cytotoxic activity against AGS cells with an IC50 of 36.9 μM. PMID:24979220

  20. Gallic acid abolishes the EGFR/Src/Akt/Erk-mediated expression of matrix metalloproteinase-9 in MCF-7 breast cancer cells.

    PubMed

    Chen, Ying-Jung; Lin, Ku-Nan; Jhang, Li-Mei; Huang, Chia-Hui; Lee, Yuan-Chin; Chang, Long-Sen

    2016-05-25

    Several studies have revealed that natural compounds are valuable resources to develop novel agents against dysregulation of the EGF/EGFR-mediated matrix metalloproteinase-9 (MMP-9) expression in cancer cells. In view of the findings that EGF/EGFR-mediated MMP-9 expression is closely related to invasion and metastasis of breast cancer. To determine the beneficial effects of gallic acid on the suppression of breast cancer metastasis, we explored the effect of gallic acid on MMP-9 expression in EGF-treated MCF-7 breast cancer cells. Treatment with EGF up-regulated MMP-9 mRNA and protein levels in MCF-7 cells. EGF treatment induced phosphorylation of EGFR and elicited Src activation, subsequently promoting Akt/NFκB (p65) and ERK/c-Jun phosphorylation in MCF-7 cells. Activation of Akt/p65 and ERK/c-Jun was responsible for the MMP-9 up-regulation in EGF-treated cells. Gallic acid repressed the EGF-induced activation of EGFR and Src; furthermore, inactivation of Akt/p65 and ERK/c-Jun was a result of the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. Over-expression of constitutively active Akt and MEK1 or over-expression of constitutively active Src eradicated the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. A chromosome conformation capture assay showed that EGF induced a chromosomal loop formation in the MMP-9 promoter via NFκB/p65 and AP-1/c-Jun activation. Treatment with gallic acid, EGFR inhibitor, or Src inhibitor reduced DNA looping. Taken together, our data suggest that gallic acid inhibits the activation of EGFR/Src-mediated Akt and ERK, leading to reduced levels of p65/c-Jun-mediated DNA looping and thus inhibiting MMP-9 expression in EGF-treated MCF-7 cells.

  1. Cobalt-catalyzed hydrogenation of esters to alcohols: unexpected reactivity trend indicates ester enolate intermediacy.

    PubMed

    Srimani, Dipankar; Mukherjee, Arup; Goldberg, Alexander F G; Leitus, Gregory; Diskin-Posner, Yael; Shimon, Linda J W; Ben David, Yehoshoa; Milstein, David

    2015-10-12

    The atom-efficient and environmentally benign catalytic hydrogenation of carboxylic acid esters to alcohols has been accomplished in recent years mainly with precious-metal-based catalysts, with few exceptions. Presented here is the first cobalt-catalyzed hydrogenation of esters to the corresponding alcohols. Unexpectedly, the evidence indicates the unprecedented involvement of ester enolate intermediates.

  2. Dichroic Liquid Crystal Displays

    NASA Astrophysics Data System (ADS)

    Bahadur, Birendra

    The following sections are included: * INTRODUCTION * DICHROIC DYES * Chemical Structure * Chemical and Photochemical Stability * THEORETICAL MODELLING * DEFECTS CAUSED BY PROLONGED LIGHT IRRADIATION * CHEMICAL STRUCTURE AND PHOTOSTABILITY * OTHER PARAMETERS AFFECTING PHOTOSTABILITY * CELL PREPARATION * DICHROIC PARAMETERS AND THEIR MEASUREMENTS * Order Parameter and Dichroic Ratio Of Dyes * Absorbance, Order Parameter and Dichroic Ratio Measurements * IMPACT OF DYE STRUCTURE AND LIQUID CRYSTAL HOST ON PHYSICAL PROPERTIES OF A DICHROIC MIXTURE * Order Parameter and Dichroic Ratio * EFFECT OF LENGTH OF DICHROIC DYES ON THE ORDER PARAMETER * EFFECT OF THE BREADTH OF DYE ON THE ORDER PARAMETER * EFFECT OF THE HOST ON THE ORDER PARAMETER * TEMPERATURE VARIATION OF THE ORDER PARAMETER OF DYES IN A LIQUID CRYSTAL HOST * IMPACT OF DYE CONCENTRATION ON THE ORDER PARAMETER * Temperature Range * Viscosity * Dielectric Constant and Anisotropy * Refractive Indices and Birefringence * solubility43,153-156 * Absorption Wavelength and Auxochromic Groups * Molecular Engineering of Dichroic Dyes * OPTICAL, ELECTRO-OPTICAL AND LIFE PARAMETERS * Colour And CIE Colour space120,160-166 * CIE 1931 COLOUR SPACE * CIE 1976 CHROMATICITY DIAGRAM * CIE UNIFORM COLOUR SPACES & COLOUR DIFFERENCE FORMULAE120,160-166 * Electro-Optical Parameters120 * LUMINANCE * CONTRAST AND CONTRAST RATIO * SWITCHING SPEED * Life Parameters and Failure Modes * DICHROIC MIXTURE FORMULATION * Monochrome Mixture * Black Mixture * ACHROMATIC BLACK MIXTURE FOR HEILMEIER DISPLAYS * Effect of Illuminant on Display Colour * Colour of the Field-On State * Effect of Dye Linewidth * Optimum Centroid Wavelengths * Effect of Dye Concentration * Mixture Formulation Using More Than Three Dyes * ACHROMATIC MIXTURE FOR WHITE-TAYLOR TYPE DISPLAYS * HEILMEIER DISPLAYS * Theoretical Modelling * Threshold Characteristic * Effects of Dye Concentration on Electro-optical Parameters * Effect of Cholesteric Doping * Effect of Alignment

  3. Phage and Yeast Display.

    PubMed

    Sheehan, Jared; Marasco, Wayne A

    2015-02-01

    Despite the availability of antimicrobial drugs, the continued development of microbial resistance--established through escape mutations and the emergence of resistant strains--limits their clinical utility. The discovery of novel, therapeutic, monoclonal antibodies (mAbs) offers viable clinical alternatives in the treatment and prophylaxis of infectious diseases. Human mAb-based therapies are typically nontoxic in patients and demonstrate high specificity for the intended microbial target. This specificity prevents negative impacts on the patient microbiome and avoids driving the resistance of nontarget species. The in vitro selection of human antibody fragment libraries displayed on phage or yeast surfaces represents a group of well-established technologies capable of generating human mAbs. The advantage of these forms of microbial display is the large repertoire of human antibody fragments present during a single selection campaign. Furthermore, the in vitro selection environments of microbial surface display allow for the rapid isolation of antibodies--and their encoding genes--against infectious pathogens and their toxins that are impractical within in vivo systems, such as murine hybridomas. This article focuses on the technologies of phage display and yeast display, as these strategies relate to the discovery of human mAbs for the treatment and vaccine development of infectious diseases. PMID:26104550

  4. 40 CFR 721.10664 - Alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and diamine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., reaction products with alkenoic acid alkyl esters and diamine (generic). 721.10664 Section 721.10664... Alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and diamine (generic). (a... generically as alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and...

  5. 40 CFR 721.10664 - Alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and diamine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., reaction products with alkenoic acid alkyl esters and diamine (generic). 721.10664 Section 721.10664... Alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and diamine (generic). (a... generically as alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and...

  6. Crewstation display interface standardization

    NASA Astrophysics Data System (ADS)

    Hardy, Gregory J.

    1999-08-01

    Military sensors and crewstation displays are all moving to digital-based technologies, an epochal shift from the previous world of analog interfaces throughout the video chain. It is no longer possible to specify a sensor and display to the same interface specification such as the venerable RS-170 and RS- 343 standards without paying an unacceptable resolution penalty. Consequently a new standard is required to allow sensor and display manufacturers to easily design system interfaces without relying on cumbersome, costly and unique interface control documents. This paper presents one possible hardware and protocol standard based on FibreChannel technology, and solicits inputs into the standards setting process which is now in progress.

  7. EKG and ultrasonoscope display

    NASA Technical Reports Server (NTRS)

    Lee, Robert D. (Inventor)

    1979-01-01

    A system is disclosed which permits simultaneous display of an EKG waveform in real time in conjunction with a two-dimensional cross-sectional image of the heart, so that the EKG waveform can be directly compared with dimensional changes in the heart. The apparatus of the invention includes an ultrasonoscope for producing a C-scan cross-sectional image of the heart. An EKG monitor circuit along with EKG logic circuitry is combined with the ultrasonoscope circuitry to produce on the same oscilloscope screen a continuous vertical trace showing the EKG waveform simultaneously with the heart image. The logic circuitry controls the oscilloscope display such that the display of both heart and EKG waveforms occurs on a real time basis.

  8. Displays, deja vu.

    PubMed

    Huntoon, R B

    1985-02-01

    Developments in electronic displays and computers have enabled avionics designers to present the pilot with ever-increasing amounts of information in greater detail and with more accuracy. However, technicological developments have not always brought about enhancement of the pilot's role as aircraft systems manager. In fact, there is evidence that the new technology may add to the pilot's workload to the extent that his performance decreases. Recent articles and reports of research indicate that application of human factor principles and procedures to: (1) develop appropriate display formats, (2) consider the total avionics suite as an integrated system, and (3) simplify or summarize related data will significantly improve total aircraft performance. Indeed, development of the "chip" and new display techniques create an imperative demand for human factor considerations early in system design, ensuring that user evaluation, information integration, and simplification are intrinsic qualities of the system.

  9. Protective effects of hydroxybenzoic acids and their esters on cell damage induced by hydroxyl radicals and hydrogen peroxides.

    PubMed

    Masaki, H; Okamoto, N; Sakaki, S; Sakurai, H

    1997-04-01

    The purpose of this study was to evaluate the hydroxyl radical scavenging activities of hydroxybenzoic acids and their esters from both chemical and biological aspects. These activities of hydroxybenzoic acids and their related compounds were estimated by ESR-spin trapping method, in which 3,4,5-trihydroxybenzoic acid and its ethyl and propyl esters showed the highest activities as estimated by IC50 value (50% inhibition concentration of hydroxyl radicals generated in the system): 78.04 +/- 11.23, 95.95 +/- 2.64, and 86.46 +/- 2.31 microM, respectively. In addition, 3,4,5-trihydroxybenzoic acid (gallic acid) at a concentration of 25 microM, protected against dermal fibroblast cell damage induced by H2O2, and enhanced the survival to 83.8 +/- 3.1%, in which the survival of control was 44.2 +/- 1.0%. Based on these results, the pretreatment effects of 3,4,5-trihydroxybenzoic acid n-alkyl esters on cell damage induced by H2O2 were examined. The survival of fibroblasts pretreated with the esters increased depending on the alkyl chain-length. Both C12 and C16 alkyl esters gave almost complete cell survival of 89.5 +/- 2.0% and 91.3 +/- 1.0%, respectively. The order of the protective effects of the compounds was in good agreement with that of their partition coefficients, suggesting that 3,4,5-trihydroxybenzoic acid alkyl esters are incorporated into fibroblasts, and thus prevent the cells from the toxicity caused by H2O2. In addition, an increase of intracellular peroxide formation in fibroblasts induced by UVA-irradiation, was suppressed to 2.27 +/- 0.41 nmol/10(4) cells by pretreatment with C16 alkyl ester at a concentration of 25 microM. Since 3,4,5-trihydroxybenzoic group has been demonstrated to possess a potent scavenging activity of hydroxyl radicals, this moiety was indicated to be important in preventing cell damage induced by UVA or H2O2: in turn, these produce hydroxyl radicals in the presence of trace metal ions such as iron and copper in cells.

  10. Thin display optical projector

    DOEpatents

    Veligdan, James T.

    1999-01-01

    An optical system (20) projects light into a planar optical display (10). The display includes laminated optical waveguides (12) defining an inlet face (14) at one end and an outlet screen (16) at an opposite end. A first mirror (26) collimates light from a light source (18) along a first axis, and distributes the light along a second axis. A second mirror (28) collimates the light from the first mirror along the second axis to illuminate the inlet face and produce an image on the screen.

  11. Integrated display scanner

    DOEpatents

    Veligdan, James T.

    2004-12-21

    A display scanner includes an optical panel having a plurality of stacked optical waveguides. The waveguides define an inlet face at one end and a screen at an opposite end, with each waveguide having a core laminated between cladding. A projector projects a scan beam of light into the panel inlet face for transmission from the screen as a scan line to scan a barcode. A light sensor at the inlet face detects a return beam reflected from the barcode into the screen. A decoder decodes the return beam detected by the sensor for reading the barcode. In an exemplary embodiment, the optical panel also displays a visual image thereon.

  12. A conjugate of the lytic peptide Hecate and gallic acid: structure, activity against cervical cancer, and toxicity.

    PubMed

    Sanches, Paulo R S; Carneiro, Bruno M; Batista, Mariana N; Braga, Ana Cláudia S; Lorenzón, Esteban N; Rahal, Paula; Cilli, Eduardo Maffud

    2015-07-01

    Conjugate compounds constitute a new class of molecules of important biological interest mainly for the treatment of diseases such as cancer. The N-terminus region of cationic peptides has been described as important for their biological activity. The aim of this study was to evaluate the lytic peptide Hecate (FALALKALKKALKKLKKALKKAL) and the effect of conjugating this macromolecule with gallic acid (C7H6O5) in terms of structure, anti-cancer activity, and toxicity. An N-terminus GA-Hecate peptide conjugate was synthesized to provide information regarding the relationship between the amino-terminal region and its charge and the secondary structure and biological activity of the peptide; and the effects of gallic acid on these parameters. Peptide secondary structure was confirmed using circular dichroism (CD). The CD measurements showed that the peptide has a high incidence of α-helical structures in the presence of SDS and LPC, while GA-Hecate presented lower incidence of α-helical structures in the same chemical environment. An evaluation of the anti-cancer activity in HeLa cancer cells indicated that both peptides are active, but that coupling gallic acid at the N-terminus decreased the activity of the free peptide. GA-Hecate showed lower activity in non-tumor keratinocyte cells but higher hemolytic activity. Our findings suggest that the N-terminus of Hecate plays an important role in its activity against cervical cancer by affecting it secondary structure, toxicity, and hemolytic activity. This study highlights the importance of the N-terminus in antitumor activity and could provide an important tool for developing new anti-cancer drugs.

  13. Gallic acid ameliorates hyperglycemia and improves hepatic carbohydrate metabolism in rats fed a high-fructose diet.

    PubMed

    Huang, Da-Wei; Chang, Wen-Chang; Wu, James Swi-Bea; Shih, Rui-Wen; Shen, Szu-Chuan

    2016-02-01

    Herein, we investigated the hypoglycemic effect of plant gallic acid (GA) on glucose uptake in an insulin-resistant cell culture model and on hepatic carbohydrate metabolism in rats with a high-fructose diet (HFD)-induced diabetes. Our hypothesis is that GA ameliorates hyperglycemia via alleviating hepatic insulin resistance by suppressing hepatic inflammation and improves abnormal hepatic carbohydrate metabolism by suppressing hepatic gluconeogenesis and enhancing the hepatic glycogenesis and glycolysis pathways in HFD-induced diabetic rats. Gallic acid increased glucose uptake activity by 19.2% at a concentration of 6.25 μg/mL in insulin-resistant FL83B mouse hepatocytes. In HFD-induced diabetic rats, GA significantly alleviated hyperglycemia, reduced the values of the area under the curve for glucose in an oral glucose tolerance test, and reduced the scores of the homeostasis model assessment of insulin resistance index. The levels of serum C-peptide and fructosamine and cardiovascular risk index scores were also significantly decreased in HFD rats treated with GA. Moreover, GA up-regulated the expression of hepatic insulin signal transduction-related proteins, including insulin receptor, insulin receptor substrate 1, phosphatidylinositol-3 kinase, Akt/protein kinase B, and glucose transporter 2, in HFD rats. Gallic acid also down-regulated the expression of hepatic gluconeogenesis-related proteins, such as fructose-1,6-bisphosphatase, and up-regulated expression of hepatic glycogen synthase and glycolysis-related proteins, including hexokinase, phosphofructokinase, and aldolase, in HFD rats. Our findings indicate that GA has potential as a health food ingredient to prevent diabetes mellitus.

  14. Quantitative Analysis and In vitro Anti-inflammatory Effects of Gallic Acid, Ellagic Acid, and Quercetin from Radix Sanguisorbae

    PubMed Central

    Seo, Chang-Seob; Jeong, Soo-Jin; Yoo, Sae-Rom; Lee, Na-Ri; Shin, Hyeun-Kyoo

    2016-01-01

    Background: Radix Sanguisorbae has long been used to treat diarrhea, enteritis, duodenal ulcers, and internal hemorrhage. Objective: We investigated the in vitro anti-inflammatory effects of Radix Sanguisorbae and performed quantitative analyses of three marker components, namely gallic acid, ellagic acid, and quercetin, using high-performance liquid chromatography coupled with a photodiode array detector. Materials and Methods: The three marker components were separated using a reversed-phase Gemini C18 analytical column maintained at 40°C by the gradient elution with two solvent systems. We examined the biological effects of the three marker compounds, gallic acid, ellagic acid, and quercetin, by determining their anti-inflammatory activities in the murine macrophage cell line RAW 264.7. Results: All of the marker compounds exhibited inhibitory effects on prostaglandin E2 production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, with no cytotoxicity. Particularly, ellagic acid significantly inhibited production of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-6 in LPS-treated RAW 264.7 cells. Conclusion: Our results suggest that ellagic acid is the most potent bioactive phytochemical component of radix Sanguisorbae in the treatment of inflammatory diseases. SUMMARY Established high-performance liquid chromatography method was applied in the quantitative analysis of gallic acid, ellagic acid, and quercetin present in an extract from radix SanguisorbaeAmong the three compounds, the ellagic acid.(7.65.mg/g) is main component in radix SanguisorbaeEllagic acid significantly inhibited production of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-6 in lipopolysaccharide-treated RAW 264.7 cells. Abbreviations used: HPLC: High-performance liquid chromatography, PDA: Photodiode array, TNF-α: Tumor necrosis factor alpha, IL: Interleukin, LPS: Lipopolysaccharide, PGE2: Prostaglandin E2, NSAIDs

  15. Intermolecular interactions in aqueous solutions of gallic acid at 296-306 K according to spectrofluorimetry and densimetry data

    NASA Astrophysics Data System (ADS)

    Grigoryan, K. R.; Sargsyan, L. S.

    2015-12-01

    Features of intermolecular interactions in aqueous solutions of gallic acid (GA) are studied by means of densimetry and fluorescence spectroscopy (intrinsic fluorescence, 2D spectra, and excitation/ emission matrix fluorescence spectra, 3D) at 296.15, 301.15, and 306.15 K in the concentration range of 5.88 × 10-4-5.88 × 10-2 mol L-1. It is shown by analyzing the concentration and temperature dependences of the apparent molar volumes and fluorescence parameters of GA that the equilibrium between nonassociated and associated species in the solution and the hydration of these species undergo changes.

  16. Experimental FTIR and theoretical studies of gallic acid-acetonitrile clusters

    NASA Astrophysics Data System (ADS)

    Hirun, Namon; Dokmaisrijan, Supaporn; Tantishaiyakul, Vimon

    2012-02-01

    Gallic acid (3,4,5-trihydroxybenzoic acid, GA) has many possible conformers depending on the orientations of its three OH and COOH groups. The biological activity of polyphenolic compounds has been demonstrated to depend on their conformational characteristics. Therefore, experimental FTIR and theoretical studies of the GA-solvent clusters were performed to investigate the possible most favored conformation of GA. Acetonitrile (ACN) was selected as the solvent since its spectrum did not interfere with the OH stretching bands of GA. Also of importance was that these OH groups, in addition to the carboxyl group, of the GA are the most likely groups to interact with receptors. The solution of GA in the ACN solution was measured and the complex OH bands were deconvoluted to four component bands. These component bands corresponded to the three OH bands on the benzene ring and a broad band which is a combination band of mainly the OH of the COOH group and the inter- and intramolecular H-bonds from the OH groups on the ring. The conformations, relative stabilities and vibrational analysis of the GA monomers and the GA-ACN clusters were investigated using the B3LYP/6-311++G(2d,2p) method. Conformational analysis of the GA monomer yielded four most possible conformers, GA-I, GA-II, GA-III and GA-IV. These conformers were subsequently used for the study of the GA:ACN clusters at the 1:1, 1:2 and 1:4 mole ratios. The IR spectra of the most stable structures of these clusters were simulated and the vibrational wavenumbers of the OH and C dbnd O groups were compared with those from the experiment. The FTIR component bands were comparable to the computed OH bands of the GA-I-(ACN) 2, GA-IV-(ACN) 2 and GA-I-(ACN) 4 clusters. Furthermore, the C dbnd O stretching bands and the bands in the regions of 1800-1000 cm -1 obtained by computing and the experiment were similar for these clusters. Thus, GA-I and GA-IV are the most preferable conformations of GA in ACN and perhaps in the

  17. The Teratogenicity and the Action Mechanism of Gallic Acid Relating with Brain and Cervical Muscles

    PubMed Central

    Hsieh, Chiu Lan; Lin, Chien-Hong; Chen, Kuan Chou; Peng, Chiung-Chi; Peng, Robert Y.

    2015-01-01

    Gallic acid (3,4,5-trihydroxybenzoic acid) (GA) and other flavanoids are extensively used in nutraceuticals because of their antioxidant and antiinflammatory properties. While examining whether GA is effective in alleviating valproic-acid-induced teratogenesis in a chicken embryo model (CEM), we observed embryo hemorrhage and liposis in the musculi longissimus cervicis. We conducted this study to determine whether GA is inherently teratogenic and the extent to which the risk can be transferred to fetuses. A CEM was used to administer GA at 2, 6, 10, and 14 μM. GA at 2 μM did not exhibit cytotoxicity. At 6, 10, and 14 μM, GA caused severe decreases in body and liver weights, causing -5.6%, -21.3%, and -27.5% body weights and 4.0, 3.8, and 3.2-g, liver weights, respectively, in day-1 chicks. The optimal alive birth rate (or damaging rate) reached 33.3%, 39.4%, and 29.2% at 6, 10, and 14 μM GA, respectively. The damaged tissue was primarily cervical muscle (musculi longissimus cervicis), as evidenced by liposis, Zenker’s necrosis, and hemolysis. The erythrocyte, hemoglobin, eosinophil, lymphocyte, and monocyte counts were severely reduced and PPAR-α was downregulated, whereas the Ras/Raf/JAK/STAT pathway was upregulated. The GA dose required to induce teratogenesis was ≥ 6 μM (1.02 mg/kg), which can be easily consumed by pregnant women in typical teas such as Chinese Pu-’Er and Chinese black teas, indicating a potential risk to human fetuses. GA at doses ≥ 1.02 mg/kg of body weight potentially causes characteristic cerebral hemolysis and liposis in the musculi longissimus cervicis. The mechanism of action of GA is multidisciplinary: The liposis can be ascribed to downregulation of PPAR-α; the erythrocyte hemolysis can be attributed to its unique autooxidative and prooxidant behavior and the inhibition of carbonic anhydrase; and the proliferation and differentiation deficits can be attributed to the upregulation of the Ras/Raf/JAK/STAT pathway. PMID

  18. Radical scavenging ability of gallic acid toward OH and OOH radicals. Reaction mechanism and rate constants from the density functional theory.

    PubMed

    Marino, Tiziana; Galano, Annia; Russo, Nino

    2014-09-01

    Gallic acid is a ubiquitous compound, widely distributed in the vegetal kingdom and frequently found in the human diet. In the present work, its primary antioxidant activity has been investigated using the density functional theory (DFT), and the quantum mechanics-based test for overall free radical scavenging activity (QM-ORSA) protocol. It was found that gallic acid is a better antioxidant than the reference compound, Trolox, regardless of the polarity of the environment. In addition, gallic acid is predicted to be among the best peroxyl radical scavengers identified so far in nonpolar (lipid) media. This compound is capable of scavenging hydroxyl radicals at diffusion-limited rates, and hydroperoxyl radicals with rate constants in the order of 10(5) M(-1) s(-1). The deprotonation of gallic acid, in aqueous solution, is predicted to increase the protective action of this compound against oxidative stress. Gallic acid was also identified as a versatile scavenger, capable of rapidly deactivating a wide variety of reactive oxygen species (ROS) and reactive nitrogen species (RNS) via electron transfer at physiological pH. PMID:25119432

  19. Gallic acid prevents isoproterenol-induced cardiac hypertrophy and fibrosis through regulation of JNK2 signaling and Smad3 binding activity

    PubMed Central

    Ryu, Yuhee; Jin, Li; Kee, Hae Jin; Piao, Zhe Hao; Cho, Jae Yeong; Kim, Gwi Ran; Choi, Sin Young; Lin, Ming Quan; Jeong, Myung Ho

    2016-01-01

    Gallic acid, a type of phenolic acid, has been shown to have beneficial effects in inflammation, vascular calcification, and metabolic diseases. The present study was aimed at determining the effect and regulatory mechanism of gallic acid in cardiac hypertrophy and fibrosis. Cardiac hypertrophy was induced by isoproterenol (ISP) in mice and primary neonatal cardiomyocytes. Gallic acid pretreatment attenuated concentric cardiac hypertrophy. It downregulated the expression of atrial natriuretic peptide, brain natriuretic peptide, and beta-myosin heavy chain in vivo and in vitro. Moreover, it prevented interstitial collagen deposition and expression of fibrosis-associated genes. Upregulation of collagen type I by Smad3 overexpression was observed in cardiac myoblast H9c2 cells but not in cardiac fibroblasts. Gallic acid reduced the DNA binding activity of phosphorylated Smad3 in Smad binding sites of collagen type I promoter in rat cardiac fibroblasts. Furthermore, it decreased the ISP-induced phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal regulated kinase (ERK) protein in mice. JNK2 overexpression reduced collagen type I and Smad3 expression as well as GATA4 expression in H9c2 cells and cardiac fibroblasts. Gallic acid might be a novel therapeutic agent for the prevention of cardiac hypertrophy and fibrosis by regulating the JNK2 and Smad3 signaling pathway. PMID:27703224

  20. Briareolate Esters from the Gorgonian Briareum asbestinum

    PubMed Central

    Meginley, Rian J.; Gupta, Prasoon; Schulz, Thomas C.; McLean, Amanda B.; Robins, Allan J.; West, Lyndon M.

    2012-01-01

    Two new briarane diterpenoids briareolate esters J (1) and K (2) were isolated from the methanolic extract of the octocoral Briareum asbestinum collected off the coast of Boca Raton, Florida. The structures of briaranes 1 and 2 were elucidated by interpretation of spectroscopic data. Briareolate ester K (2) showed weak growth inhibition activity against human embryonic stem cells (BG02). PMID:23015768

  1. Sugar Ester Compounds for Arthropod Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugar esters, also known as acyl sugars or polyol esters, are a class of compounds that are internationally recognized as food additives. They are commonly used in bakery goods, drugs, cosmetics, food packaging plastics, and in other applications because of their surfactant and emulsifying properti...

  2. Drivers license display system

    NASA Astrophysics Data System (ADS)

    Prokoski, Francine J.

    1997-01-01

    Carjackings are only one of a growing class of law enforcement problems associated with increasingly violent crimes and accidents involving automobiles plays weapons, drugs and alcohol. Police traffic stops have become increasingly dangerous, with an officer having no information about a vehicle's potentially armed driver until approaching him. There are 15 million alcoholics in the US and 90 percent of them have drivers licenses. Many of them continue driving even after their licenses have ben revoked or suspended. There are thousands of unlicensed truck drivers in the country, and also thousands who routinely exceed safe operating periods without rest; often using drugs in an attempt to stay alert. MIKOS has developed the Drivers License Display Systems to reduce these and other related risks. Although every state requires the continuous display of vehicle registration information on every vehicle using public roads, no state yet requires the display of driver license information. The technology exists to provide that feature as an add-on to current vehicles for nominal cost. An initial voluntary market is expected to include: municipal, rental, and high value vehicles which are most likely to be mis-appropriated. It is anticipated that state regulations will eventually require such systems in the future, beginning with commercial vehicles, and then extending to high risk drivers and eventually all vehicles. The MIKOS system offers a dual-display approach which can be deployed now, and which will utilize all existing state licenses without requiring standardization.

  3. Refreshing Refreshable Braille Displays.

    PubMed

    Russomanno, Alexander; O'Modhrain, Sile; Gillespie, R Brent; Rodger, Matthew W M

    2015-01-01

    The increased access to books afforded to blind people via e-publishing has given them long-sought independence for both recreational and educational reading. In most cases, blind readers access materials using speech output. For some content such as highly technical texts, music, and graphics, speech is not an appropriate access modality as it does not promote deep understanding. Therefore blind braille readers often prefer electronic braille displays. But, these are prohibitively expensive. The search is on, therefore, for a low-cost refreshable display that would go beyond current technologies and deliver graphical content as well as text. And many solutions have been proposed, some of which reduce costs by restricting the number of characters that can be displayed, even down to a single braille cell. In this paper, we demonstrate that restricting tactile cues during braille reading leads to poorer performance in a letter recognition task. In particular, we show that lack of sliding contact between the fingertip and the braille reading surface results in more errors and that the number of errors increases as a function of presentation speed. These findings suggest that single cell displays which do not incorporate sliding contact are likely to be less effective for braille reading. PMID:25879973

  4. Christmas Light Display

    NASA Astrophysics Data System (ADS)

    Ross, Arthur; Renfro, Timothy

    2012-03-01

    The Digital Electronics class at McMurry University created a Christmas light display that toggles the power of different strands of lights, according to what frequencies are played in a song, as an example of an analog to digital circuit. This was accomplished using a BA3830S IC six-band audio filter and six solid-state relays.

  5. Refreshing Refreshable Braille Displays.

    PubMed

    Russomanno, Alexander; O'Modhrain, Sile; Gillespie, R Brent; Rodger, Matthew W M

    2015-01-01

    The increased access to books afforded to blind people via e-publishing has given them long-sought independence for both recreational and educational reading. In most cases, blind readers access materials using speech output. For some content such as highly technical texts, music, and graphics, speech is not an appropriate access modality as it does not promote deep understanding. Therefore blind braille readers often prefer electronic braille displays. But, these are prohibitively expensive. The search is on, therefore, for a low-cost refreshable display that would go beyond current technologies and deliver graphical content as well as text. And many solutions have been proposed, some of which reduce costs by restricting the number of characters that can be displayed, even down to a single braille cell. In this paper, we demonstrate that restricting tactile cues during braille reading leads to poorer performance in a letter recognition task. In particular, we show that lack of sliding contact between the fingertip and the braille reading surface results in more errors and that the number of errors increases as a function of presentation speed. These findings suggest that single cell displays which do not incorporate sliding contact are likely to be less effective for braille reading.

  6. Virtual acoustic displays

    NASA Technical Reports Server (NTRS)

    Wenzel, Elizabeth M.

    1991-01-01

    A 3D auditory display can potentially enhance information transfer by combining directional and iconic information in a quite naturalistic representation of dynamic objects in the interface. Another aspect of auditory spatial clues is that, in conjunction with other modalities, it can act as a potentiator of information in the display. For example, visual and auditory cues together can reinforce the information content of the display and provide a greater sense of presence or realism in a manner not readily achievable by either modality alone. This phenomenon will be particularly useful in telepresence applications, such as advanced teleconferencing environments, shared electronic workspaces, and monitoring telerobotic activities in remote or hazardous situations. Thus, the combination of direct spatial cues with good principles of iconic design could provide an extremely powerful and information-rich display which is also quite easy to use. An alternative approach, recently developed at ARC, generates externalized, 3D sound cues over headphones in realtime using digital signal processing. Here, the synthesis technique involves the digital generation of stimuli using Head-Related Transfer Functions (HRTF's) measured in the two ear-canals of individual subjects. Other similar approaches include an analog system developed by Loomis, et. al., (1990) and digital systems which make use of transforms derived from normative mannikins and simulations of room acoustics. Such an interface also requires the careful psychophysical evaluation of listener's ability to accurately localize the virtual or synthetic sound sources. From an applied standpoint, measurement of each potential listener's HRTF's may not be possible in practice. For experienced listeners, localization performance was only slightly degraded compared to a subject's inherent ability. Alternatively, even inexperienced listeners may be able to adapt to a particular set of HRTF's as long as they provide adequate

  7. The esters of carboxylic nutrients as insulinotropic tools in non-insulin-dependent diabetes mellitus.

    PubMed

    Malaisse, W J

    1995-10-01

    1. In non-insulin-dependent diabetes mellitus, the pancreatic B-cell displays a preferential impairment of its secretory response to D-glucose. 2. A number of agents could be used to restore secretory activity in the diseased B-cell. 3. In this respect, esters of carboxylic nutrients, such as succinic or glutamic acid, present the advantages of stimulating both proinsulin biosynthesis and insulin release, remaining efficient in models of B-cell glucotoxicity, augmenting the secretory response to hypoglycemic pharmacological agents, protecting the B-cell against cytotoxic aggressions, and exerting a long-term beneficial effect upon the secretory potential of the endocrine pancreas. 4. Potential limitations of this new therapeutical approach, such as the generation of methanol from the esters, their postulated inefficacy after enteral administration, or the occurrence of extrapancreatic metabolic effects may be circumvented. 5. The esters of carboxylic nutrients could even be used in other cells endangered by ATP depletion. PMID:7590101

  8. Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

    PubMed

    Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

    2013-07-01

    A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation.

  9. Synthesis and biological evaluation of arctigenin ester and ether derivatives as activators of AMPK.

    PubMed

    Shen, Sida; Zhuang, Jingjing; Chen, Yijia; Lei, Min; Chen, Jing; Shen, Xu; Hu, Lihong

    2013-07-01

    A series of new arctigenin and 9-deoxy-arctigenin derivatives bearing different ester and ether side chains at the phenolic hydroxyl positions are designed, synthesized, and evaluated for activating AMPK potency in L6 myoblasts. Initial biological evaluation indicates that some alkyl ester and phenethyl ether arctigenin derivatives display potential activities in AMPK phosphorylation improvement. Further structure-activity relationship analysis shows that arctigenin ester derivatives 3a, 3h and 9-deoxy-arctigenin phenethyl ether derivatives 6a, 6c, 6d activate AMPK more potently than arctigenin. Moreover, the 2-(3,4-dimethoxyphenyl)ethyl ether moiety of 6c has been demonstrated as a potential functional group to improve the effect of AMPK phosphorylation. The structural optimization of arctigenin leads to the identification of 6c as a promising lead compound that exhibits excellent activity in AMPK activation. PMID:23673223

  10. Antifungal properties of halofumarate esters.

    PubMed

    Gershon, H; Shanks, L

    1978-04-01

    Alkyl esters (C1--C4) of the four halofumaric acids were tested for antifungal activity against Candida albicans, Aspergillus niger, Mucor mucedo, and Trichophyton mentagrophytes at pH 5.6 and 7.0 in the absence and presence of 10% beef serum in Sabouraud dextrose agar. The most toxic compound to each organism was: C. albicans, ethyl iodofumarate (0.054 mmole/liter); A. niger, methyl bromofumarate (0.090 mmole/liter); M. mucedo, methyl fluorofumarate (0.037 mmole/liter); and T. mentagrophytes, ethyl iodofumarate (0.020 mmole/liter). The order of overall activity of the six most toxic compounds was: ethyl iodofumarate greater than ethyl chlorofumarate greater than methyl iodofumarate = methyl bromofumarate greater than methyl chlorofumarate greater than bromofumarate.

  11. Quantum chemical density functional theory studies on the molecular structure and vibrational spectra of Gallic acid imprinted polymers

    NASA Astrophysics Data System (ADS)

    Pardeshi, Sushma; Dhodapkar, Rita; Kumar, Anupama

    2013-12-01

    Gallic acid (GA) is known by its antioxidant, anticarcinogenic properties and scavenger activity against several types of harmful free radicals. Molecularly imprinted polymers (MIPs) are used in separation of a pure compound from complex matrices. A stable template-monomer complex generates the MIPs with the highest affinity and selectivity for the template. The quantum chemical computations based on density functional theory (DFT) was used on the template Gallic acid (GA), monomer acrylic acid (AA) and GA-AA complex to study the nature of interactions involved in the GA-AA complex. B3LYP/6-31+G(2d,2p) model chemistry was used to optimize their structures and frequency calculations. The effect of porogen acetonitrile (ACN) on complex formation was included by using polarizable continuum model (PCM). The results demonstrated the formation of a stable GA-AA complex through the intermolecular hydrogen bonding between carboxylic acid groups of GA and AA. The Mulliken atomic charge analysis and simulated vibrational spectra also supported the stable hydrogen bonding interaction between the carboxylic acid groups of GA and AA with minimal interference of porogen ACN. Further, simulations on GA-AA mole ratio revealed that 1:4 GA-AA was optimum for synthesis of MIP for GA.

  12. Pharmacophore modeling, molecular docking, QSAR, and in silico ADMET studies of gallic acid derivatives for immunomodulatory activity.

    PubMed

    Yadav, Dharmendra Kumar; Khan, Feroz; Negi, Arvind Singh

    2012-06-01

    Immunomodulation refers to an alteration in the immune response due to the intrusion of foreign molecules into the body. In the present communication, QSAR and docking studies of gallic acid derivatives were performed in relation to their immunomodulatory activities. Screening through the use of a QSAR model suggested that the compounds G-4, G-7, G-9, G-10, G-12, and G-13 possess immunomodulatory activity. Activity was predicted using a statistical model developed by the forward stepwise multiple linear regression method. The correlation coefficient (r(2)) and the prediction accuracy (rCV(2)) of the QSAR model were 0.99 and 0.96, respectively. The QSAR study indicated that chemical descriptors-dipole moment, steric energy, amide group count, λ(max) (UV-visible) and molar refractivity-are well correlated with activity, while decreases in the dipole moment, steric energy, and molar refractivity were negatively correlated. A molecular docking study showed that the compounds had high binding affinities for the INFα-2, IL-6, and IL-4 receptors. Binding site residues formed H-bonds with the designed gallic acid derivatives G-3, G-4, G-5, G-6, G-7, and G-10. Moreover, based on screening for oral bioavailability, in silico ADME, and toxicity risk assessment, we concluded that compound G-7 exhibits marked immunomodulatory activity, comparable to levamisole.

  13. Quantum chemical density functional theory studies on the molecular structure and vibrational spectra of Gallic acid imprinted polymers.

    PubMed

    Pardeshi, Sushma; Dhodapkar, Rita; Kumar, Anupama

    2013-12-01

    Gallic acid (GA) is known by its antioxidant, anticarcinogenic properties and scavenger activity against several types of harmful free radicals. Molecularly imprinted polymers (MIPs) are used in separation of a pure compound from complex matrices. A stable template-monomer complex generates the MIPs with the highest affinity and selectivity for the template. The quantum chemical computations based on density functional theory (DFT) was used on the template Gallic acid (GA), monomer acrylic acid (AA) and GA-AA complex to study the nature of interactions involved in the GA-AA complex. B3LYP/6-31+G(2d,2p) model chemistry was used to optimize their structures and frequency calculations. The effect of porogen acetonitrile (ACN) on complex formation was included by using polarizable continuum model (PCM). The results demonstrated the formation of a stable GA-AA complex through the intermolecular hydrogen bonding between carboxylic acid groups of GA and AA. The Mulliken atomic charge analysis and simulated vibrational spectra also supported the stable hydrogen bonding interaction between the carboxylic acid groups of GA and AA with minimal interference of porogen ACN. Further, simulations on GA-AA mole ratio revealed that 1:4 GA-AA was optimum for synthesis of MIP for GA.

  14. Text File Display Program

    NASA Technical Reports Server (NTRS)

    Vavrus, J. L.

    1986-01-01

    LOOK program permits user to examine text file in pseudorandom access manner. Program provides user with way of rapidly examining contents of ASCII text file. LOOK opens text file for input only and accesses it in blockwise fashion. Handles text formatting and displays text lines on screen. User moves forward or backward in file by any number of lines or blocks. Provides ability to "scroll" text at various speeds in forward or backward directions.

  15. Microgap flat panel display

    DOEpatents

    Wuest, Craig R.

    1998-01-01

    A microgap flat panel display which includes a thin gas-filled display tube that utilizes switched X-Y "pixel" strips to trigger electron avalanches and activate a phosphor at a given location on a display screen. The panel utilizes the principal of electron multiplication in a gas subjected to a high electric field to provide sufficient electron current to activate standard luminescent phosphors located on an anode. The X-Y conductive strips of a few micron widths may for example, be deposited on opposite sides of a thin insulating substrate, or on one side of the adjacent substrates and function as a cathode. The X-Y strips are separated from the anode by a gap filled with a suitable gas. Electrical bias is selectively switched onto X and Y strips to activate a "pixel" in the region where these strips overlap. A small amount of a long-lived radioisotope is used to initiate an electron avalanche in the overlap region when bias is applied. The avalanche travels through the gas filled gap and activates a luminescent phosphor of a selected color. The bias is adjusted to give a proportional electron multiplication to control brightness for given pixel.

  16. Microgap flat panel display

    DOEpatents

    Wuest, C.R.

    1998-12-08

    A microgap flat panel display is disclosed which includes a thin gas-filled display tube that utilizes switched X-Y ``pixel`` strips to trigger electron avalanches and activate a phosphor at a given location on a display screen. The panel utilizes the principal of electron multiplication in a gas subjected to a high electric field to provide sufficient electron current to activate standard luminescent phosphors located on an anode. The X-Y conductive strips of a few micron widths may for example, be deposited on opposite sides of a thin insulating substrate, or on one side of the adjacent substrates and function as a cathode. The X-Y strips are separated from the anode by a gap filled with a suitable gas. Electrical bias is selectively switched onto X and Y strips to activate a ``pixel`` in the region where these strips overlap. A small amount of a long-lived radioisotope is used to initiate an electron avalanche in the overlap region when bias is applied. The avalanche travels through the gas filled gap and activates a luminescent phosphor of a selected color. The bias is adjusted to give a proportional electron multiplication to control brightness for given pixel. 6 figs.

  17. Attention-Seeking Displays

    PubMed Central

    Számadó, Szabolcs

    2015-01-01

    Animal communication abounds with extravagant displays. These signals are usually interpreted as costly signals of quality. However, there is another important function for these signals: to call the attention of the receiver to the signaller. While there is abundant empirical evidence to show the importance of this stage, it is not yet incorporated into standard signalling theory. Here I investigate a general model of signalling - based on a basic action-response game - that incorporates this searching stage. I show that giving attention-seeking displays and searching for them can be an ESS. This is a very general result and holds regardless whether only the high quality signallers or both high and low types give them. These signals need not be costly at the equilibrium and they need not be honest signals of any quality, as their function is not to signal quality but simply to call the attention of the potential receivers. These kind of displays are probably more common than their current weight in the literature would suggest. PMID:26287489

  18. Engine monitoring display study

    NASA Technical Reports Server (NTRS)

    Hornsby, Mary E.

    1992-01-01

    The current study is part of a larger NASA effort to develop displays for an engine-monitoring system to enable the crew to monitor engine parameter trends more effectively. The objective was to evaluate the operational utility of adding three types of information to the basic Boeing Engine Indicating and Crew Alerting System (EICAS) display formats: alphanumeric alerting messages for engine parameters whose values exceed caution or warning limits; alphanumeric messages to monitor engine parameters that deviate from expected values; and a graphic depiction of the range of expected values for current conditions. Ten training and line pilots each flew 15 simulated flight scenarios with five variants of the basic EICAS format; these variants included different combinations of the added information. The pilots detected engine problems more quickly when engine alerting messages were included in the display; adding a graphic depiction of the range of expected values did not affect detection speed. The pilots rated both types of alphanumeric messages (alert and monitor parameter) as more useful and easier to interpret than the graphic depiction. Integrating engine parameter messages into the EICAS alerting system appears to be both useful and preferred.

  19. Allelopathic potential and ecotoxicity evaluation of gallic and nonanoic acids to prevent cyanobacterial growth in lentic systems: A preliminary mesocosm study.

    PubMed

    Techer, Didier; Fontaine, Pascal; Personne, Aline; Viot, Sandrine; Thomas, Marielle

    2016-03-15

    The increase in anthropogenic nutrient loading affecting many freshwater ecosystems combined with global warming may lead to cyanobacterial blooms on an increasingly frequent basis. Among the various physicochemical and biological methods which have been proposed to rapidly control blue-green algae growth, the use of plant-derived substances such as allelochemicals has gained great interest as an environment-friendly approach. The primary aim of this work was to evaluate the efficiency of gallic and nonanoic acid application to preemptively inhibit cyanobacterial growth in lentic hydrosystems. In order to address the process feasibility under realistic exposure scenarios, thirteen outdoor freshwater mesocosms (unit volume: 3m(3)) were designed, each containing phytoplankton (including local blue-green algae species) and various non-target organisms from higher trophic levels (Physa, Lymnaea, Gammarus, and Scardinius erythrophthalmus). After an 8-week mesocosm stabilization period, a full factorial design based on the presence/absence of gallic acid (GA) and nonanoic acid (NA) (including a control group) was implemented into the exposure tanks. Regular monitoring of major phytoplankton taxa was conducted during a 28-day experiment using an on-line fluorometer. The main results suggested that gallic acid was more efficient than nonanoic acid at limiting cyanobacterial growth at concentrations as low as 1 mg L(-1). Successive gallic acid applications (at 1, 2 and 4 mg L(-1)) at the early stages of cyanobacterial growth did not allow the complete elimination of blue-green algae from the mesocosms. However, the specificity of the allelopathic effect of gallic acid towards cyanobacteria was compatible with the maintenance of a primary productivity in the treated tanks as indicated by the photoautotrophic growth of other algal taxa. Finally, no biomarker induction signal could be reported in non-target species. Further gallic acid application trials in lentic systems such

  20. Gallic acid indanone and mangiferin xanthone are strong determinants of immunosuppressive anti-tumour effects of Mangifera indica L. bark in MDA-MB231 breast cancer cells.

    PubMed

    García-Rivera, Dagmar; Delgado, René; Bougarne, Nadia; Haegeman, Guy; Berghe, Wim Vanden

    2011-06-01

    Vimang is a standardized extract derived from Mango bark (Mangifera Indica L.), commonly used as anti-inflammatory phytomedicine, which has recently been used to complement cancer therapies in cancer patients. We have further investigated potential anti-tumour effects of glucosylxanthone mangiferin and indanone gallic acid, which are both present in Vimang extract. We observed significant anti-tumour effects of both Vimang constituents in the highly aggressive and metastatic breast cancer cell type MDA-MB231. At the molecular level, mangiferin and gallic acid both inhibit classical NFκB activation by IKKα/β kinases, which results in impaired IκB degradation, NFκB translocation and NFκB/DNA binding. In contrast to the xanthone mangiferin, gallic acid further inhibits additional NFκB pathways involved in cancer cell survival and therapy resistance, such as MEK1, JNK1/2, MSK1, and p90RSK. This results in combinatorial inhibition of NFκB activity by gallic acid, which results in potent inhibition of NFκB target genes involved in inflammation, metastasis, anti-apoptosis and angiogenesis, such as IL-6, IL-8, COX2, CXCR4, XIAP, bcl2, VEGF. The cumulative NFκB inhibition by gallic acid, but not mangiferin, is also reflected at the level of cell survival, which reveals significant tumour cytotoxic effects in MDA-MB231 cells. Altogether, we identify gallic acid, besides mangiferin, as an essential anti-cancer component in Vimang extract, which demonstrates multifocal inhibition of NFκB activity in the cancer-inflammation network.

  1. Allelopathic potential and ecotoxicity evaluation of gallic and nonanoic acids to prevent cyanobacterial growth in lentic systems: A preliminary mesocosm study.

    PubMed

    Techer, Didier; Fontaine, Pascal; Personne, Aline; Viot, Sandrine; Thomas, Marielle

    2016-03-15

    The increase in anthropogenic nutrient loading affecting many freshwater ecosystems combined with global warming may lead to cyanobacterial blooms on an increasingly frequent basis. Among the various physicochemical and biological methods which have been proposed to rapidly control blue-green algae growth, the use of plant-derived substances such as allelochemicals has gained great interest as an environment-friendly approach. The primary aim of this work was to evaluate the efficiency of gallic and nonanoic acid application to preemptively inhibit cyanobacterial growth in lentic hydrosystems. In order to address the process feasibility under realistic exposure scenarios, thirteen outdoor freshwater mesocosms (unit volume: 3m(3)) were designed, each containing phytoplankton (including local blue-green algae species) and various non-target organisms from higher trophic levels (Physa, Lymnaea, Gammarus, and Scardinius erythrophthalmus). After an 8-week mesocosm stabilization period, a full factorial design based on the presence/absence of gallic acid (GA) and nonanoic acid (NA) (including a control group) was implemented into the exposure tanks. Regular monitoring of major phytoplankton taxa was conducted during a 28-day experiment using an on-line fluorometer. The main results suggested that gallic acid was more efficient than nonanoic acid at limiting cyanobacterial growth at concentrations as low as 1 mg L(-1). Successive gallic acid applications (at 1, 2 and 4 mg L(-1)) at the early stages of cyanobacterial growth did not allow the complete elimination of blue-green algae from the mesocosms. However, the specificity of the allelopathic effect of gallic acid towards cyanobacteria was compatible with the maintenance of a primary productivity in the treated tanks as indicated by the photoautotrophic growth of other algal taxa. Finally, no biomarker induction signal could be reported in non-target species. Further gallic acid application trials in lentic systems such

  2. 40 CFR 721.10679 - Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester (generic). 721.10679 Section 721... Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester... identified generically as carboxylic acid, substituted alkylstannylene ester, reaction products...

  3. Stage Cylindrical Immersive Display

    NASA Technical Reports Server (NTRS)

    Abramyan, Lucy; Norris, Jeffrey S.; Powell, Mark W.; Mittman, David S.; Shams, Khawaja S.

    2011-01-01

    Panoramic images with a wide field of view intend to provide a better understanding of an environment by placing objects of the environment on one seamless image. However, understanding the sizes and relative positions of the objects in a panorama is not intuitive and prone to errors because the field of view is unnatural to human perception. Scientists are often faced with the difficult task of interpreting the sizes and relative positions of objects in an environment when viewing an image of the environment on computer monitors or prints. A panorama can display an object that appears to be to the right of the viewer when it is, in fact, behind the viewer. This misinterpretation can be very costly, especially when the environment is remote and/or only accessible by unmanned vehicles. A 270 cylindrical display has been developed that surrounds the viewer with carefully calibrated panoramic imagery that correctly engages their natural kinesthetic senses and provides a more accurate awareness of the environment. The cylindrical immersive display offers a more natural window to the environment than a standard cubic CAVE (Cave Automatic Virtual Environment), and the geometry allows multiple collocated users to simultaneously view data and share important decision-making tasks. A CAVE is an immersive virtual reality environment that allows one or more users to absorb themselves in a virtual environment. A common CAVE setup is a room-sized cube where the cube sides act as projection planes. By nature, all cubic CAVEs face a problem with edge matching at edges and corners of the display. Modern immersive displays have found ways to minimize seams by creating very tight edges, and rely on the user to ignore the seam. One significant deficiency of flat-walled CAVEs is that the sense of orientation and perspective within the scene is broken across adjacent walls. On any single wall, parallel lines properly converge at their vanishing point as they should, and the sense of

  4. Structural Control of Bisurea-Based Supramolecular Polymers: Influence of an Ester Moiety.

    PubMed

    Dirany, Mohammed; Ayzac, Virgile; Isare, Benjamin; Raynal, Matthieu; Bouteiller, Laurent

    2015-10-27

    A few examples of monomers are known that self-assemble into various high molar mass structures in solution. Controlling the morphology of the resulting supramolecular polymers is a highly desirable goal for many applications. Herein, we compare the self-assembling properties of newly prepared ester bisurea monomers with those of previously investigated alkyl bisurea monomers. The ester functionality decreases the hydrogen bonding strength of the bisurea monomers but does not prevent the formation of long assemblies in nonpolar solvents: gels are formed at millimolar concentration. Surprisingly, ester bisureas self-assemble at room temperature into rod-like urea-bonded supramolecular polymers that are different from the ones formed by alkyl bisureas. The rods formed by ester bisurea supramolecular polymers are compact (instead of tubular in the case of alkyl bisureas) and display two monomers in the cross-section (instead of three in the case of alkyl bisureas). The stability of the structures formed by ester bisureas can be easily tuned by changing the nature of the substituent in the α-position of the urea functions and/or the nature of the alkyl side chains. PMID:26461519

  5. Sunflower oil methyl ester as diesel fuel

    SciTech Connect

    Hassett, D.J.; Hasan, R.A.

    1982-01-01

    Methyl ester formation represents one approach to overcome the problems associated with the relatively high viscosity of sunflower oil when used as a diesel fuel replacement. Sunflower oil methyl ester is being prepared at the University of North Dakota Engieering Experiment Station. Physical and chemical properties of this material at varying levels of refinement and purity will be used to define fuel properties. Engine testing is being carried out to determine if the fouling characteristics of methyl ester are significantly less than those of sunflower oil. 1 figure, 1 table.

  6. Landing Hazard Avoidance Display

    NASA Technical Reports Server (NTRS)

    Abernathy, Michael Franklin (Inventor); Hirsh, Robert L. (Inventor)

    2016-01-01

    Landing hazard avoidance displays can provide rapidly understood visual indications of where it is safe to land a vehicle and where it is unsafe to land a vehicle. Color coded maps can indicate zones in two dimensions relative to the vehicles position where it is safe to land. The map can be simply green (safe) and red (unsafe) areas with an indication of scale or can be a color coding of another map such as a surface map. The color coding can be determined in real time based on topological measurements and safety criteria to thereby adapt to dynamic, unknown, or partially known environments.

  7. Synthesis of a new energetic nitrate ester

    SciTech Connect

    Chavez, David E

    2008-01-01

    Nitrate esters have been known as useful energetic materials since the discovery of nitroglycerin by Ascanio Sobrero in 1846. The development of methods to increase the safety and utility of nitroglycerin by Alfred Nobel led to the revolutionary improvement in the utility of nitroglycerin in explosive applications in the form of dynamite. Since then, many nitrate esters have been prepared and incorporated into military applications such as double-based propellants, detonators and as energetic plasticizers. Nitrate esters have also been shown to have vasodilatory effects in humans and thus have been studied and used for treatments of ailments such as angina. The mechanism of the biological response towards nitrate esters has been elucidated recently. Interestingly, many of the nitrate esters used for military purposes are liquids (ethylene glycol dinitrate, propylene glycol dinitrate, etc). Pentaerythritol tetranitrate (PETN) is one of the only solid nitrate esters, besides nitrocellulose, that is used in any application. Unfortunately, PETN melting point is above 100 {sup o}C, and thus must be pressed as a solid for detonator applications. A more practical material would be a melt-castable explosive, for potential simplification of manufacturing processes. Herein we describe the synthesis of a new energetic nitrate ester (1) that is a solid at ambient temperatures, has a melting point of 85-86 {sup o}C and has the highest density of any known nitrate ester composed only of carbon, hydrogen, nitrogen and oxygen. We also describe the chemical, thermal and sensitivity properties of 1 as well as some preliminary explosive performance data.

  8. Latest development of display technologies

    NASA Astrophysics Data System (ADS)

    Gao, Hong-Yue; Yao, Qiu-Xiang; Liu, Pan; Zheng, Zhi-Qiang; Liu, Ji-Cheng; Zheng, Hua-Dong; Zeng, Chao; Yu, Ying-Jie; Sun, Tao; Zeng, Zhen-Xiang

    2016-09-01

    In this review we will focus on recent progress in the field of two-dimensional (2D) and three-dimensional (3D) display technologies. We present the current display materials and their applications, including organic light-emitting diodes (OLEDs), flexible OLEDs quantum dot light emitting diodes (QLEDs), active-matrix organic light emitting diodes (AMOLEDs), electronic paper (E-paper), curved displays, stereoscopic 3D displays, volumetric 3D displays, light field 3D displays, and holographic 3D displays. Conventional 2D display devices, such as liquid crystal devices (LCDs) often result in ambiguity in high-dimensional data images because of lacking true depth information. This review thus provides a detailed description of 3D display technologies.

  9. Allied, MGC link on cyanate esters

    SciTech Connect

    Wood, A.

    1993-02-24

    In the latest of a line of joint ventures in its plastics business, Allied Signal has reached agreement with Mitsubishi Gas Chemical (MGC) to jointly develop thermoset cyanate ester resins and blends. The deal will involve further development of Allied Signal's Primaset phenol-formaldehyde cyanate ester resins, a new entrant in the thermoset arena. Although the Primaset resins were discovered in the 1960s, this would be the first time they are available commercially. The deal will marry Primaset technology with MGC's Skylex bisphenol A cyanate ester resins, says Fred DiAntonis, director/advanced materials at Allied Signal. The two firms are looking at marketing blends of the two materials. The potential market for these resins, used commercially by the electronics industry in printed circuit boards and by the aerospace industry in composites, is significant, says Robert P. Viarengo, Allied Signal president/performance materials. By aligning ourselves with MGC, the world leader in cyanate ester resin, we anticipate moving forward aggressively. The main competitor is Ciba, which acquired bisphenol A cyanate ester resins with its purchase of Rhone-Poulenc's high temperature resins business. DiAntonis estimates the market for cyanate ester resins could be worth $150 million by the end of the decade, although development costs have been in the tens of millions of dollars range.

  10. Antioxidant activity of gallic acid and methyl gallate in triacylglycerols of Kilka fish oil and its oil-in-water emulsion.

    PubMed

    Asnaashari, Maryam; Farhoosh, Reza; Sharif, Ali

    2014-09-15

    The anti-DPPH radical effect as well as anti-peroxide activity of gallic acid, methyl gallate, and α-tocopherol in a bulk Kilka fish oil and its oil-in-water emulsion stabilized by soy protein isolate at 55°C were investigated. Gallic acid with the lowest hydrophobicity (log P=-0.28) was found to be the most active antiradical agent (IC50=29.5 μM), followed by methyl gallate (IC50=38.0 μM, log P=-0.23) and α-tocopherol (IC50=105.3 μM, log P=0.70). The anti-peroxide activity in the bulk oil system decreased in the order of methyl gallate>gallic acid>α-tocopherol. In the emulsion system, methyl gallate still behaved better than gallic acid, but the highest activity belonged to α-tocopherol. Based on the calculation of a number of kinetic parameters, the antioxidants, in general, showed better performances in the bulk oil system than in the emulsion system.

  11. [Effect of gallic acid derivatives on secretion of Th1 cytokines and Th2 cytokines from anti CD3-stimulated spleen cells].

    PubMed

    Kato, K; Yamashita, S; Kitanaka, S; Toyoshima, S

    2001-06-01

    As reported previously (Kosuge et al., Yakugaku Zasshi, 120, 408 (2000)), methyl gallate, a gallic acid derivative, which has been one of compounds isolated from extracts of Psidium geneus Myrtaceae, selectively suppresses Th2 cytokine secretion. In the present study, to examine more effective compounds than methyl gallate, the effects of various gallic acid derivatives on the secretion of helper T cell subtype specific cytokines from anti CD3-stimulated spleen cells were investigated. Ten micrograms/ml of methyl gallate and ethyl gallate remarkably suppressed the secretion of IL-4 and IL-5, Th2 cytokines, but did not suppress meaningfully the secretion of IFN-gamma, a Th1 cytokine. On the other hand, the other gallic acid derivatives suppressed the secretion of both IL-4 and IFN-gamma. Ten micrograms/ml of methyl gallate suppressed the secretion of IL-2, a Th1 cytokine, but the same concentration of ethyl gallate did not suppress it. In conclusion, it seemed that ethyl gallate was the most selective inhibitor for the secretion of Th2 cytokines among gallic acid derivatives used in this study.

  12. Gallic acid reduces the effect of LPS on apoptosis and inhibits the formation of neutrophil extracellular traps.

    PubMed

    Haute, Gabriela Viegas; Caberlon, Eduardo; Squizani, Eamim; de Mesquita, Fernanda Cristina; Pedrazza, Leonardo; Martha, Bianca Andrade; da Silva Melo, Denizar Alberto; Cassel, Eduardo; Czepielewski, Rafael Sanguinetti; Bitencourt, Shanna; Goettert, Márcia Inês; de Oliveira, Jarbas Rodrigues

    2015-12-25

    Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. Apoptosis can be delayed by the presence of pathogens or chemical components such as lipopolysaccharide (LPS). Neutrophils have other antimicrobial strategy, called neutrophil extracellular traps (NETs), which contributes to the elimination and control of the pathogen. NETosis is induced by infection, inflammation or trauma and represents an innate immune activation mechanism. The objective of this study was to evaluate the effect of gallic acid (GA) in the modulation of apoptosis and NETs release. The results show that GA decreased the anti-apoptotic effect of LPS, blocked the induction of NETs and prevented the formation of free radicals induced by LPS. These findings demonstrate that the GA is a novel therapeutic agent for decreasing the exacerbated response of the body against an infectious agent.

  13. Gallic acid reduces the effect of LPS on apoptosis and inhibits the formation of neutrophil extracellular traps.

    PubMed

    Haute, Gabriela Viegas; Caberlon, Eduardo; Squizani, Eamim; de Mesquita, Fernanda Cristina; Pedrazza, Leonardo; Martha, Bianca Andrade; da Silva Melo, Denizar Alberto; Cassel, Eduardo; Czepielewski, Rafael Sanguinetti; Bitencourt, Shanna; Goettert, Márcia Inês; de Oliveira, Jarbas Rodrigues

    2015-12-25

    Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. Apoptosis can be delayed by the presence of pathogens or chemical components such as lipopolysaccharide (LPS). Neutrophils have other antimicrobial strategy, called neutrophil extracellular traps (NETs), which contributes to the elimination and control of the pathogen. NETosis is induced by infection, inflammation or trauma and represents an innate immune activation mechanism. The objective of this study was to evaluate the effect of gallic acid (GA) in the modulation of apoptosis and NETs release. The results show that GA decreased the anti-apoptotic effect of LPS, blocked the induction of NETs and prevented the formation of free radicals induced by LPS. These findings demonstrate that the GA is a novel therapeutic agent for decreasing the exacerbated response of the body against an infectious agent. PMID:26475966

  14. Black optic display

    DOEpatents

    Veligdan, James T.

    1997-01-01

    An optical display includes a plurality of stacked optical waveguides having first and second opposite ends collectively defining an image input face and an image screen, respectively, with the screen being oblique to the input face. Each of the waveguides includes a transparent core bound by a cladding layer having a lower index of refraction for effecting internal reflection of image light transmitted into the input face to project an image on the screen, with each of the cladding layers including a cladding cap integrally joined thereto at the waveguide second ends. Each of the cores is beveled at the waveguide second end so that the cladding cap is viewable through the transparent core. Each of the cladding caps is black for absorbing external ambient light incident upon the screen for improving contrast of the image projected internally on the screen.

  15. Anti-Inflammatory Activities of Pentaherbs Formula, Berberine, Gallic Acid and Chlorogenic Acid in Atopic Dermatitis-Like Skin Inflammation.

    PubMed

    Tsang, Miranda S M; Jiao, Delong; Chan, Ben C L; Hon, Kam-Lun; Leung, Ping C; Lau, Clara B S; Wong, Eric C W; Cheng, Ling; Chan, Carmen K M; Lam, Christopher W K; Wong, Chun K

    2016-04-20

    Atopic dermatitis (AD) is a common allergic skin disease, characterized by dryness, itchiness, thickening and inflammation of the skin. Infiltration of eosinophils into the dermal layer and presence of edema are typical characteristics in the skin biopsy of AD patients. Previous in vitro and clinical studies showed that the Pentaherbs formula (PHF) consisting of five traditional Chinese herbal medicines, Flos Lonicerae, Herba Menthae, Cortex Phellodendri, Cortex Moutan and Rhizoma Atractylodis at w/w ratio of 2:1:2:2:2 exhibited therapeutic potential in treating AD. In this study, an in vivo murine model with oxazolone (OXA)-mediated dermatitis was used to elucidate the efficacy of PHF. Active ingredients of PHF water extract were also identified and quantified, and their in vitro anti-inflammatory activities on pruritogenic cytokine IL-31- and alarmin IL-33-activated human eosinophils and dermal fibroblasts were evaluated. Ear swelling, epidermis thickening and eosinophils infiltration in epidermal and dermal layers, and the release of serum IL-12 of the murine OXA-mediated dermatitis were significantly reduced upon oral or topical treatment with PHF (all p < 0.05). Gallic acid, chlorogenic acid and berberine contents (w/w) in PHF were found to be 0.479%, 1.201% and 0.022%, respectively. Gallic acid and chlorogenic acid could suppress the release of pro-inflammatory cytokine IL-6 and chemokine CCL7 and CXCL8, respectively, in IL-31- and IL-33-treated eosinophils-dermal fibroblasts co-culture; while berberine could suppress the release of IL-6, CXCL8, CCL2 and CCL7 in the eosinophil culture and eosinophils-dermal fibroblasts co-culture (all p < 0.05). These findings suggest that PHF can ameliorate allergic inflammation and attenuate the activation of eosinophils.

  16. Simultaneous EKG and ultrasonoscope display

    NASA Technical Reports Server (NTRS)

    Lee, R. D.

    1977-01-01

    Display of two dimensional image of heart and EKG waveform concurrently on same cathode-ray, is achieved by device. Concurrent display allows continuous comparision of dimensional changes in heart and periodicity of EKG waveform.

  17. Human factors of visual displays

    NASA Technical Reports Server (NTRS)

    Snyder, H. L.

    1984-01-01

    Several human factors issues in visual displays are addressed in this report. They are as follows: (1) the importance of luminance range and contrast; (2) uniformity of visual displays; (3) image quality; (4) color contrast; and (5) dot matrix fonts.

  18. Esterase SeE of Streptococcus equi ssp. equi is a Novel Non-specific Carboxylic Ester Hydrolase

    PubMed Central

    Xie, Gang; Liu, Mengyao; Zhu, Hui; Lei, Benfang

    2009-01-01

    Extracellular carboxylic ester hydrolases are produced by many bacterial pathogens and have been shown recently to be important for virulence of some pathogens. However, these hydrolases are poorly characterized in enzymatic activity. This study prepared and characterized the secreted ester hydrolase of Streptococcus equi ssp. equi (designated SeE for S. equi esterase). SeE hydrolyzes ethyl acetate, acetylsalicylic acid, and tributyrin but not ethyl butyrate. This substrate specificity pattern does not match those of the three conventional types of non-specific carboxylic ester hydrolases (carboxylesterases, arylesterases, and acetylesterases). To determine whether SeE has lipase activity, a number of triglycerides and vinyl esters were tested in SeE-catalyzed hydrolysis. SeE does not hydrolyze triglycerides and vinyl esters of long chain carboxylic acids nor display interfacial activation, indicating that SeE is not a lipase. Like the conventional carboxylesterases, SeE is inhibited by diisopropylfluorophosphate. These findings indicate that SeE is a novel non-specific carboxylic ester hydrolase that has broader substrate specificity than the conventional carboxylesterases. PMID:19054107

  19. Influence of Grape Composition on Red Wine Ester Profile: Comparison between Cabernet Sauvignon and Shiraz Cultivars from Australian Warm Climate.

    PubMed

    Antalick, Guillaume; Šuklje, Katja; Blackman, John W; Meeks, Campbell; Deloire, Alain; Schmidtke, Leigh M

    2015-05-13

    The relationship between grape composition and subsequent red wine ester profile was examined. Cabernet Sauvignon and Shiraz, from the same Australian very warm climate vineyard, were harvested at two different stages of maturity and triplicate wines were vinified. Grape analyses focused on nitrogen and lipid composition by measuring 18 amino acids by HPLC-FLD, 3 polyunsaturated fatty acids, and 6 C6-compounds derived from lipid degradation by GC-MS. Twenty esters and four higher alcohols were analyzed in wines by HS-SPME-GC-MS. Concentrations of the ethyl esters of branched acids were significantly affected by grape maturity, but the variations were inconsistent between cultivars. Small relative variations were observed between wines for ethyl esters of fatty acids, whereas higher alcohol acetates displayed the most obvious differences with concentrations ranging from 1.5- to 26-fold higher in Shiraz than in Cabernet Sauvignon wines regardless of the grape maturity. Grape analyses revealed the variations of wine ester composition might be related to specific grape juice nitrogen composition and lipid metabolism. To the authors' knowledge the present study is the first to investigate varietal differences in the ester profiles of Shiraz and Cabernet Sauvignon wines made with grapes harvested at different maturity stages.

  20. Detection of testosterone esters in blood.

    PubMed

    Forsdahl, Guro; Erceg, Damir; Geisendorfer, Thomas; Turkalj, Mirjana; Plavec, Davor; Thevis, Mario; Tretzel, Laura; Gmeiner, Günter

    2015-01-01

    Injections of synthetic esters of testosterone are among the most common forms of testosterone application. In doping control, the detection of an intact ester of testosterone in blood gives unequivocal proof of the administration of exogenous testosterone. The aim of the current project was to investigate the detection window for injected testosterone esters as a mixed substance preparation and as a single substance preparation in serum and plasma. Furthermore, the suitability of different types of blood collection devices was evaluated. Collection tubes with stabilizing additives, as well as non-stabilized serum separation tubes, were tested. A clinical study with six participants was carried out, comprising a single intramuscular injection of either 1000 mg testosterone undecanoate (Nebido(®)) or a mixture of 30 mg testosterone propionate, 60 mg testosterone phenylpropionate, 60 mg testosterone isocaproate, and 100 mg testosterone decanoate (Sustanon(®)). Blood was collected throughout a testing period of 60 days. The applied analytical method for blood analysis included liquid-liquid extraction and preparation of oxime derivatives, prior to TLX-sample clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection. All investigated testosterone esters could be detected in post-administration blood samples. The detection time depended on the type of ester administered. Furthermore, results from the study show that measured blood concentrations of especially short-chained testosterone esters are influenced by the type of blood collection device applied. The testosterone ester detection window, however, was comparable. PMID:26695486

  1. Detection of testosterone esters in blood.

    PubMed

    Forsdahl, Guro; Erceg, Damir; Geisendorfer, Thomas; Turkalj, Mirjana; Plavec, Davor; Thevis, Mario; Tretzel, Laura; Gmeiner, Günter

    2015-01-01

    Injections of synthetic esters of testosterone are among the most common forms of testosterone application. In doping control, the detection of an intact ester of testosterone in blood gives unequivocal proof of the administration of exogenous testosterone. The aim of the current project was to investigate the detection window for injected testosterone esters as a mixed substance preparation and as a single substance preparation in serum and plasma. Furthermore, the suitability of different types of blood collection devices was evaluated. Collection tubes with stabilizing additives, as well as non-stabilized serum separation tubes, were tested. A clinical study with six participants was carried out, comprising a single intramuscular injection of either 1000 mg testosterone undecanoate (Nebido(®)) or a mixture of 30 mg testosterone propionate, 60 mg testosterone phenylpropionate, 60 mg testosterone isocaproate, and 100 mg testosterone decanoate (Sustanon(®)). Blood was collected throughout a testing period of 60 days. The applied analytical method for blood analysis included liquid-liquid extraction and preparation of oxime derivatives, prior to TLX-sample clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection. All investigated testosterone esters could be detected in post-administration blood samples. The detection time depended on the type of ester administered. Furthermore, results from the study show that measured blood concentrations of especially short-chained testosterone esters are influenced by the type of blood collection device applied. The testosterone ester detection window, however, was comparable.

  2. Developing Intepretive Soil Education Displays.

    ERIC Educational Resources Information Center

    Hansmeyer, T. L.; Cooper, T. H.

    1993-01-01

    Describes several soil educational displays developed for park and nature center trails. Displays include full-scale soil monoliths displayed along the trails with explanations on why and how the soils are different, and micro-monoliths exhibiting the different soil types. (MDH)

  3. Gallic Acid, an active constituent of grape seed extract, exhibits anti-proliferative, pro-apoptotic and anti-tumorigenic effects against prostate carcinoma xenograft growth in nude mice

    PubMed Central

    Kaur, Manjinder; Velmurugan, Balaiya; Rajamanickam, Subapriya; Agarwal, Rajesh; Agarwal, Chapla

    2009-01-01

    Purpose Gallic acid, a natural agent present wide-range of fruits and vegetables, has been of potential interest as anti-cancer agent; herein, we evaluated its efficacy in androgen-independent DU145 and androgen-dependent-22Rv1 human prostate cancer (PCa) cells Materials and Methods Cell viability was determined by MTT and apoptosis by Annexin V-PI assays. In vivo anti-cancer efficacy was assessed by DU145 and 22Rv1 xenograft growth in nude mice given normal drinking water or one supplemented with 0.3% or 1% (w/v) gallic acid. PCNA, TUNEL and CD31 immunostaining was performed in tumor tissues for in vivo anti-proliferative, apoptotic and anti-angiogenic effects of gallic acid. Results Gallic acid decreased cell viability in a dose-dependent manner in both DU145 and 22Rv1 cells largely via apoptosis induction. In tumor studies, gallic acid feeding inhibited the growth of DU145 and 22Rv1 PCa xenografts in nude mice. Immunohistochemical analysis revealed significant inhibition of tumor cell proliferation, induction of apoptosis, and reduction of microvessel density in tumor xenografts from gallic acid-fed mice as compared to controls in both DU145 and 22Rv1 models Conclusion Taken together, our findings show the anti-PCa efficacy of gallic acid providing a rationale for additional studies with this naturally-occurring agent for its efficacy against PCa. PMID:19543955

  4. LED instrument approach instruction display

    NASA Technical Reports Server (NTRS)

    Meredith, B. D.; Kelly, W. L., IV; Crouch, R. K.

    1979-01-01

    A display employing light emitting diodes (LED's) was developed to demonstrate the feasibility of such displays for presenting landing and navigation information to reduce the workload of general aviation pilots during IFR flight. The display consists of a paper tape reader, digital memory, control electronics, digital latches, and LED alphanumeric displays. A presentable digital countdown clock-timer is included as part of the system to provide a convenient means of monitoring time intervals for precise flight navigation. The system is a limited capability prototype assembled to test pilot reaction to such a device under simulated IFR operation. Pilot opinion indicates that the display is helpful in reducing the IFR pilots workload when used with a runway approach plate. However, the development of a compact, low power second generation display was recommended which could present several instructions simultaneously and provide information update capability. A microprocessor-based display could fulfill these requirements.

  5. Unique interactive projection display screen

    SciTech Connect

    Veligdan, J.T.

    1997-11-01

    Projection systems continue to be the best method to produce large (1 meter and larger) displays. However, in order to produce a large display, considerable volume is typically required. The Polyplanar Optic Display (POD) is a novel type of projection display screen, which for the first time, makes it possible to produce a large projection system that is self-contained and only inches thick. In addition, this display screen is matte black in appearance allowing it to be used in high ambient light conditions. This screen is also interactive and can be remotely controlled via an infrared optical pointer resulting in mouse-like control of the display. Furthermore, this display need not be flat since it can be made curved to wrap around a viewer as well as being flexible.

  6. Signal Processing, Analysis, & Display

    1986-06-01

    SIG is a general-purpose signal processing, analysis, and display program. Its main purpose is to perform manipulations on time- and frequency-domain signals. However, it has been designed to ultimately accommodate other representations for data such as multiplexed signals and complex matrices. Two user interfaces are provided in SIG - a menu mode for the unfamiliar user and a command mode for more experienced users. In both modes errors are detected as early as possible andmore » are indicated by friendly, meaningful messages. An on-line HELP package is also included. A variety of operations can be performed on time- and frequency-domain signals including operations on the samples of a signal, operations on the entire signal, and operations on two or more signals. Signal processing operations that can be performed are digital filtering (median, Bessel, Butterworth, and Chebychev), ensemble average, resample, auto and cross spectral density, transfer function and impulse response, trend removal, convolution, Fourier transform and inverse window functions (Hamming, Kaiser-Bessel), simulation (ramp, sine, pulsetrain, random), and read/write signals. User definable signal processing algorithms are also featured. SIG has many options including multiple commands per line, command files with arguments,commenting lines, defining commands, and automatic execution for each item in a repeat sequence. Graphical operations on signals and spectra include: x-y plots of time signals; real, imaginary, magnitude, and phase plots of spectra; scaling of spectra for continuous or discrete domain; cursor zoom; families of curves; and multiple viewports.« less

  7. Trimerization of monocyanate ester in nanopores.

    PubMed

    Koh, Yung P; Simon, Sindee L

    2010-06-17

    The effects of nanoconfinement on the reaction kinetics and properties of a monocyanate ester and the resulting cyanurate trimer are studied using differential scanning calorimetry (DSC). On the basis of both dynamic heating scans and isothermal reaction studies, the reaction rate is found to increase with decreasing nanopore size without a change in reaction mechanism. Both the monocyanate ester reactant and cyanurate product show reduced glass transition temperatures (T(g)s) as compared to the bulk; the T(g) depression increases with conversion and is more pronounced for the fully reacted product, suggesting that molecular stiffness influences the magnitude of nanoconfinement effects. Our results are consistent with the accelerated reaction and the T(g) depression found previously for the nanoconfined difunctional cyanate ester, supporting the supposition that intracyclization is not the origin of these effects. PMID:20496921

  8. Molecular Basis of Prodrug Activation by Human Valacyclovirase, an [alpha]-Amino Acid Ester Hydrolase

    SciTech Connect

    Lai, Longsheng; Xu, Zhaohui; Zhou, Jiahai; Lee, Kyung-Dall; Amidon, Gordon L.

    2008-07-08

    Chemical modification to improve biopharmaceutical properties, especially oral absorption and bioavailability, is a common strategy employed by pharmaceutical chemists. The approach often employs a simple structural modification and utilizes ubiquitous endogenous esterases as activation enzymes, although such enzymes are often unidentified. This report describes the crystal structure and specificity of a novel activating enzyme for valacyclovir and valganciclovir. Our structural insights show that human valacyclovirase has a unique binding mode and specificity for amino acid esters. Biochemical data demonstrate that the enzyme hydrolyzes esters of {alpha}-amino acids exclusively and displays a broad specificity spectrum for the aminoacyl moiety similar to tricorn-interacting aminopeptidase F1. Crystal structures of the enzyme, two mechanistic mutants, and a complex with a product analogue, when combined with biochemical analysis, reveal the key determinants for substrate recognition; that is, a flexible and mostly hydrophobic acyl pocket, a localized negative electrostatic potential, a large open leaving group-accommodating groove, and a pivotal acidic residue, Asp-123, after the nucleophile Ser-122. This is the first time that a residue immediately after the nucleophile has been found to have its side chain directed into the substrate binding pocket and play an essential role in substrate discrimination in serine hydrolases. These results as well as a phylogenetic analysis establish that the enzyme functions as a specific {alpha}-amino acid ester hydrolase. Valacyclovirase is a valuable target for amino acid ester prodrug-based oral drug delivery enhancement strategies.

  9. Mono- and tri-ester hydrogenolysis using tandem catalysis. Scope and mechanism.

    SciTech Connect

    Lohr, Tracy L.; Li, Zhi; Assary, Rajeev S.; Curtiss, Larry A.; Marks, Tobin J.

    2016-01-01

    The scope and mechanism of thermodynamically leveraged ester RC(O)O-R' bond hydrogenolysis by tandem metal triflate + supported Pd catalysts are investigated both experimentally and theoretically by DFT and energy span analysis. This catalytic system has a broad scope, with relative cleavage rates scaling as, tertiary 4 secondary 4 primary ester at 1 bar H-2, yielding alkanes and carboxylic acids with high conversion and selectivity. Benzylic and allylic esters display the highest activity. The rate law is nu = k[M(OTf )(n)](1)[ester](0)[H-2](0) with an H/D kinetic isotope effect = 6.5 +/- 0.5, implying turnover-limiting C-H scission following C-O cleavage, in agreement with theory. Intermediate alkene products are then rapidly hydrogenated. Applying this approach with the very active Hf(OTf)(4) catalyst to bio-derived triglycerides affords near-quantitative yields of C-3 hydrocarbons rather than glycerol. From model substrates, it is found that RC(O)O-R' cleavage rates are very sensitive to steric congestion and metal triflate identity. For triglycerides, primary/external glyceryl CH2-O cleavage predominates over secondary/internal CH-O cleavage, with the latter favored by less acidic or smaller ionic radius metal triflates, raising the diester selectivity to as high as 48% with Ce(OTf)(3).

  10. Augmenting digital displays with computation

    NASA Astrophysics Data System (ADS)

    Liu, Jing

    As we inevitably step deeper and deeper into a world connected via the Internet, more and more information will be exchanged digitally. Displays are the interface between digital information and each individual. Naturally, one fundamental goal of displays is to reproduce information as realistically as possible since humans still care a lot about what happens in the real world. Human eyes are the receiving end of such information exchange; therefore it is impossible to study displays without studying the human visual system. In fact, the design of displays is rather closely coupled with what human eyes are capable of perceiving. For example, we are less interested in building displays that emit light in the invisible spectrum. This dissertation explores how we can augment displays with computation, which takes both display hardware and the human visual system into consideration. Four novel projects on display technologies are included in this dissertation: First, we propose a software-based approach to driving multiview autostereoscopic displays. Our display algorithm can dynamically assign views to hardware display zones based on multiple observers' current head positions, substantially reducing crosstalk and stereo inversion. Second, we present a dense projector array that creates a seamless 3D viewing experience for multiple viewers. We smoothly interpolate the set of viewer heights and distances on a per-vertex basis across the arrays field of view, reducing image distortion, crosstalk, and artifacts from tracking errors. Third, we propose a method for high dynamic range display calibration that takes into account the variation of the chrominance error over luminance. We propose a data structure for enabling efficient representation and querying of the calibration function, which also allows user-guided balancing between memory consumption and the amount of computation. Fourth, we present user studies that demonstrate that the ˜ 60 Hz critical flicker fusion

  11. Advanced poly-LED displays

    NASA Astrophysics Data System (ADS)

    Childs, Mark; Nisato, Giovanni; Fish, D.; Giraldo, Andrea; Jenkins, A. J.; Johnson, Mark T.

    2003-05-01

    Philips have been actively developing polymer OLED (poly-LED) displays as a future display technology. Their emissive nature leads to a very attractive visual appearance, with wide viewing angle, high brightness and fast response speed. Whilst the first generation of poly-LED displays are likely to be passive-matrix driven, power reduction and resolution increase will lead to the use of active-matrix poly-LED displays. Philips Research have designed, fabricated and characterized five different designs of active-matrix polymer-LED display. Each of the five displays makes use of a distinct pixel programming- or pixel drive-technique, including current programming, threshold voltage measurement and photodiode feedback. It will be shown that hte simplest voltage-programmed current-source pixel suffers from potentially unacceptable brightness non-uniformity, and that advanced pixel circuits can provide a solution to this. Optical-feedback pixel circuits will be discussed, showing that they can be used to improve uniformity and compensate for image burn-in due to polymer-LED material degradation, improving display lifetime. Philips research has also been active in developing technologies required to implement poly-LED displays on flexible substrates, including materials, processing and testing methods. The fabrication of flexible passive-matrix poly-LED displays will be presented, as well as the ongoing work to assess the suitability of processing flexible next-generation poly-LED displays.

  12. Rapid display of radiographic images

    NASA Astrophysics Data System (ADS)

    Cox, Jerome R., Jr.; Moore, Stephen M.; Whitman, Robert A.; Blaine, G. James; Jost, R. Gilbert; Karlsson, L. M.; Monsees, Thomas L.; Hassen, Gregory L.; David, Timothy C.

    1991-07-01

    The requirements for the rapid display of radiographic images exceed the capabilities of widely available display, computer, and communications technologies. Computed radiography captures data with a resolution of about four megapixels. Large-format displays are available that can present over four megapixels. One megapixel displays are practical for use in combination with large-format displays and in areas where the viewing task does not require primary diagnosis. This paper describes an electronic radiology system that approximates the highest quality systems, but through the use of several interesting techniques allows the possibility of its widespread installation throughout hospitals. The techniques used can be grouped under three major system concepts: a local, high-speed image server, one or more physician's workstations each with one or more high-performance auxiliary displays specialized to the radiology viewing task, and dedicated, high-speed communication links between the server and the displays. This approach is enhanced by the use of a progressive transmission scheme to decrease the latency for viewing four megapixel images. The system includes an image server with storage for over 600 4-megapixel images and a high-speed link. A subsampled megapixel image is fetched from disk and transmitted to the display in about one second followed by the full resolution 4-megapixel image in about 2.5 seconds. Other system components include a megapixel display with a 6-megapixel display memory space and frame-rate update of image roam, zoom, and contrast. Plans for clinical use are presented.

  13. Phthalate esters: Testing for ecological effects

    SciTech Connect

    Brown, D.; Thompson, R.; Croudace, C.; Stewart, K.; Williams, N.

    1995-12-31

    Ortho-phthalate esters are produced in high tonnages for use as plasticizers, in particular for PVC. Their physical chemical properties are typically very low water solubility and high octanol/water partition coefficient. This combination of properties presents a number of experimental difficulties in the design and interpretation of ecological effect studies. These difficulties are described and results presented showing techniques for the performance of reproduction studies with the water flea, Daphnia magna, in aqueous solution and with the midge, Chironomus riparius, in sediments. The results which showed no effect for the phthalate esters tested are discussed in the context of other ecotoxicity data obtained on these products.

  14. X-1 on display

    NASA Technical Reports Server (NTRS)

    1949-01-01

    A Bell Aircraft Corporation X-1 series aircraft on display at an Open House at NACA Muroc Flight Test Unit or High-Speed Flight Research Station hangar on South Base of Edwards Air Force Base, California. (The precise date of the photo is uncertain, but it is probably before 1948.) The instrumentation that was carried aboard the aircraft to gather data is on display. The aircraft data was recorded on oscillograph film that was read, calibrated, and converted into meaningful parameters for the engineers to evaluate from each research flight. In the background of the photo are several early U.S. jets. These include several Lockheed P-80 Shooting Stars, which were used as chase planes on X-1 flights; two Bell P-59 Airacomets, the first U.S. jet pursuit aircraft (fighter in later parlance); and a prototype Republic XP-84 Thunderjet. There were five versions of the Bell X-1 rocket-powered research aircraft that flew at the NACA High-Speed Flight Research Station, Edwards, California. The bullet-shaped X-1 aircraft were built by Bell Aircraft Corporation, Buffalo, N.Y. for the U.S. Army Air Forces (after 1947, U.S. Air Force) and the National Advisory Committee for Aeronautics (NACA). The X-1 Program was originally designated the XS-1 for eXperimental Sonic. The X-1's mission was to investigate the transonic speed range (speeds from just below to just above the speed of sound) and, if possible, to break the 'sound barrier.' Three different X-1s were built and designated: X-1-1, X-1-2 (later modified to become the X-1E), and X-1-3. The basic X-1 aircraft were flown by a large number of different pilots from 1946 to 1951. The X-1 Program not only proved that humans could go beyond the speed of sound, it reinforced the understanding that technological barriers could be overcome. The X-1s pioneered many structural and aerodynamic advances including extremely thin, yet extremely strong wing sections; supersonic fuselage configurations; control system requirements; powerplant

  15. Laser illuminated flat panel display

    SciTech Connect

    Veligdan, J.T.

    1995-12-31

    A 10 inch laser illuminated flat panel Planar Optic Display (POD) screen has been constructed and tested. This POD screen technology is an entirely new concept in display technology. Although the initial display is flat and made of glass, this technology lends itself to applications where a plastic display might be wrapped around the viewer. The display screen is comprised of hundreds of planar optical waveguides where each glass waveguide represents a vertical line of resolution. A black cladding layer, having a lower index of refraction, is placed between each waveguide layer. Since the cladding makes the screen surface black, the contrast is high. The prototype display is 9 inches wide by 5 inches high and approximately I inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.

  16. Affinity labelling enzymes with esters of aromatic sulfonic acids

    DOEpatents

    Wong, Show-Chu; Shaw, Elliott

    1977-01-01

    Novel esters of aromatic sulfonic acids are disclosed. The specific esters are nitrophenyl p- and m-amidinophenylmethanesulfonate. Also disclosed is a method for specific inactivation of the enzyme, thrombin, employing nitrophenyl p-amidinophenylmethanesulfonate.

  17. 21 CFR 172.735 - Glycerol ester of rosin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CONSUMPTION Other Specific Usage Additives § 172.735 Glycerol ester of rosin. Glycerol ester of wood rosin... purified by countercurrent steam distillation or steam stripping. (b) It is used to adjust the density...

  18. 21 CFR 172.735 - Glycerol ester of rosin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CONSUMPTION Other Specific Usage Additives § 172.735 Glycerol ester of rosin. Glycerol ester of wood rosin... purified by countercurrent steam distillation or steam stripping. (b) It is used to adjust the density...

  19. Novel Membrane Based Process for Producing Lactate Esters

    SciTech Connect

    1999-02-01

    Lactate Esters from Renewable Carbohydrate Feedstocks can Replace Petroleum-Derived Solvents. Lactate esters are versatile solvents that are biodegradable, nontoxic, and applicable to a wide range of industrial and consumer uses.

  20. Flat panel planar optic display

    SciTech Connect

    Veligdan, J.T.

    1994-11-01

    A prototype 10 inch flat panel Planar Optic Display, (POD), screen has been constructed and tested. This display screen is comprised of hundreds of planar optic class sheets bonded together with a cladding layer between each sheet where each glass sheet represents a vertical line of resolution. The display is 9 inches wide by 5 inches high and approximately 1 inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.

  1. Peripheral vision displays: The future

    NASA Technical Reports Server (NTRS)

    Assenhein, H. M.

    1984-01-01

    Several areas of research relating to peripheral vision displays used by aircraft pilots are outlined: fiber optics, display color, and holography. Various capacities and specifications of gas and solid state lasers are enumerated. These lasers are potential sources of green light for the peripheral vision displays. The relative radiance required for rod and cone vision at different wavelengths is presented graphically. Calculated and measured retinal sensitivities (foveal and peripheral) are given for wavelength produced by various lasers.

  2. The display of tactile information

    NASA Technical Reports Server (NTRS)

    Sherrick, Carl E.

    1991-01-01

    There are a number of examples of natural tactile displays that can five us some insights about the solid geometry of touch, and recent experimental work on the subject has extended our thinking considerably. The concern of here is, however, more with synthetic or artificial displays for the production of a virtual environment. Features of synthetic displays that have enjoyed some success in one of the following two enterprises are discussed: the study of the spatio-temporal dimensions of stimuli that afford accurate and rapid processing of environmental information, or the use of displays in the design of sensory aids for disabled persons.

  3. Colorimetric evaluation of display performance

    NASA Astrophysics Data System (ADS)

    Kosmowski, Bogdan B.

    2001-08-01

    The development of information techniques, using new technologies, physical phenomena and coding schemes, enables new application areas to be benefited form the introduction of displays. The full utilization of the visual perception of a human operator, requires the color coding process to be implemented. The evolution of displays, from achromatic (B&W) and monochromatic, to multicolor and full-color, enhances the possibilities of information coding, creating however a need for the quantitative methods of display parameter assessment. Quantitative assessment of color displays, restricted to photometric measurements of their parameters, is an estimate leading to considerable errors. Therefore, the measurements of a display's color properties have to be based on spectral measurements of the display and its elements. The quantitative assessment of the display system parameters should be made using colorimetric systems like CIE1931, CIE1976 LAB or LUV. In the paper, the constraints on the measurement method selection for the color display evaluation are discussed and the relations between their qualitative assessment and the ergonomic conditions of their application are also presented. The paper presents the examples of using LUV colorimetric system and color difference (Delta) E in the optimization of color liquid crystal displays.

  4. Liquid crystal Fresnel lens display

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-Qian; Abhishek Kumar, Srivastava; Alwin Tam, Ming-Wai; Zheng, Zhi-Gang; Shen, Dong; Vladimir, Chigrinov G.; Kwok, Hoi-Sing

    2016-09-01

    A novel see-through display with a liquid crystal lens array was proposed. A liquid crystal Fresnel lens display (LCFLD) with a holographic screen was demonstrated. The proposed display system has high efficiency, simple fabrication, and low manufacturing cost due to the absence of a polarizer and color filter. Project supported by Partner State Key Laboratory on Advanced Displays and Optoelectronics Technologies HKUST, China, the National Natural Science Foundation of China (Grant Nos. 61435008 and 61575063), and the Fundamental Research Funds for the Central Universities, China (Grant No. WM1514036).

  5. Liquid crystal Fresnel lens display

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-Qian; Abhishek Kumar, Srivastava; Alwin Tam, Ming-Wai; Zheng, Zhi-Gang; Shen, Dong; Vladimir, Chigrinov G.; Kwok, Hoi-Sing

    2016-09-01

    A novel see-through display with a liquid crystal lens array was proposed. A liquid crystal Fresnel lens display (LCFLD) with a holographic screen was demonstrated. The proposed display system has high efficiency, simple fabrication, and low manufacturing cost due to the absence of a polarizer and color filter. Project supported by Partner State Key Laboratory on Advanced Displays and Optoelectronics Technologies HKUST, China, the National Natural Science Foundation of China (Grant Nos. 61435008 and 61575063), and the Fundamental Research Funds for the Central Universities, China (Grant No. WM1514036).

  6. Maintenance Procedure Display: Head Mounted Display (HMD) Evaluations

    NASA Technical Reports Server (NTRS)

    Whitmore, Milrian; Litaker, Harry L., Jr.; Solem, Jody A.; Holden, Kritina L.; Hoffman, Ronald R.

    2007-01-01

    A viewgraph presentation describing maintenance procedures for head mounted displays is shown. The topics include: 1) Study Goals; 2) Near Eye Displays (HMDs); 3) Design; 4) Phase I-Evaluation Methods; 5) Phase 1 Results; 6) Improved HMD Mounting; 7) Phase 2 -Evaluation Methods; 8) Phase 2 Preliminary Results; and 9) Next Steps.

  7. Methyl-3-O-methyl gallate and gallic acid from the leaves of Peltiphyllum peltatum: isolation and comparative antioxidant, prooxidant, and cytotoxic effects in neuronal cells.

    PubMed

    Habtemariam, Solomon

    2011-11-01

    Methyl-3-O-methyl gallate (M3MG) is a rare natural product with close structural similarity to gallic acid. In the present report, the isolation of M3MG from Peltiphyllum peltatum leaves and its comparative antioxidant, prooxidant, and cytotoxicity to neuronal SH-SY5Y cells are discussed. When tested in concentrations up to 1 mM, M3MG consistently showed antioxidant activity without prooxidant effect both in cell and cell-free assay models. In contrast to M3MG, gallic acid showed a copper-dependent prooxidant effect that resulted in DNA damage, increased the level of intracellular reactive oxygen species, and induced cytotoxicity in neuronal cells. The identification of M3MG in P. peltatum leaves is furtherz evidence of the great antioxidant potential and nutritional value of the plant.

  8. Oxidative stability of estolide esters using PDSC

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estolides are obtained by the formation of a carbocation that can undergo nucleophilic addition with or without carbocation migration along the length of the chain. The carboxylic acid functionality of one fatty acid links to the site of unsaturation of another fatty acid to form oligomeric esters. ...

  9. Avocado and olive oil methyl esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, incl...

  10. QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis

    NASA Technical Reports Server (NTRS)

    Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

    1985-01-01

    Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of catonic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR'P(O)X, where R and R' are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrogen hydrolysis rate constant.

  11. 40 CFR 721.10255 - Vinyl carboxylic acid ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Vinyl carboxylic acid ester (generic... Specific Chemical Substances § 721.10255 Vinyl carboxylic acid ester (generic). (a) Chemical substance and... carboxylic acid ester (PMN P-09-400) is subject to reporting under this section for the significant new...

  12. 40 CFR 721.10255 - Vinyl carboxylic acid ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Vinyl carboxylic acid ester (generic... Specific Chemical Substances § 721.10255 Vinyl carboxylic acid ester (generic). (a) Chemical substance and... carboxylic acid ester (PMN P-09-400) is subject to reporting under this section for the significant new...

  13. 40 CFR 721.10255 - Vinyl carboxylic acid ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Vinyl carboxylic acid ester (generic... Specific Chemical Substances § 721.10255 Vinyl carboxylic acid ester (generic). (a) Chemical substance and... carboxylic acid ester (PMN P-09-400) is subject to reporting under this section for the significant new...

  14. 21 CFR 172.854 - Polyglycerol esters of fatty acids.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Polyglycerol esters of fatty acids. 172.854... § 172.854 Polyglycerol esters of fatty acids. Polyglycerol esters of fatty acids, up to and including..., safflower oil, sesame oil, soybean oil, and tallow and the fatty acids derived from these...

  15. 40 CFR 721.2825 - Alkyl ester (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkyl ester (generic name). 721.2825... Substances § 721.2825 Alkyl ester (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance alkyl ester (PMN P-84-968) is subject to reporting under this...

  16. 40 CFR 721.2825 - Alkyl ester (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkyl ester (generic name). 721.2825... Substances § 721.2825 Alkyl ester (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance alkyl ester (PMN P-84-968) is subject to reporting under this...

  17. 40 CFR 721.2825 - Alkyl ester (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkyl ester (generic name). 721.2825... Substances § 721.2825 Alkyl ester (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance alkyl ester (PMN P-84-968) is subject to reporting under this...

  18. 40 CFR 721.2825 - Alkyl ester (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkyl ester (generic name). 721.2825... Substances § 721.2825 Alkyl ester (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance alkyl ester (PMN P-84-968) is subject to reporting under this...

  19. 40 CFR 721.2825 - Alkyl ester (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl ester (generic name). 721.2825... Substances § 721.2825 Alkyl ester (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance alkyl ester (PMN P-84-968) is subject to reporting under this...

  20. 21 CFR 172.848 - Lactylic esters of fatty acids.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Lactylic esters of fatty acids. 172.848 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids may be safely used in food in accordance with the following prescribed conditions: (a)...

  1. 21 CFR 172.848 - Lactylic esters of fatty acids.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Lactylic esters of fatty acids. 172.848 Section... § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids may be safely used in food in accordance with the following prescribed conditions: (a) They are prepared from lactic acid and fatty...

  2. 21 CFR 172.848 - Lactylic esters of fatty acids.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Lactylic esters of fatty acids. 172.848 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids may be safely used in food in accordance with the following prescribed conditions: (a)...

  3. Synthesis and physical properties of new estolide esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estolides are a class of esters based on vegetable oils that, in this case, are formed when the carboxylic acid functionality of one fatty acid reacts at the site of unsaturation of another fatty acid to form an ester linkage. The objective of this preliminary study was to synthesize new esters of e...

  4. 40 CFR 721.4215 - Hexanedioic acid, diethenyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Hexanedioic acid, diethenyl ester. 721... Substances § 721.4215 Hexanedioic acid, diethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexanedioic acid, diethenyl ester (PMN...

  5. 40 CFR 721.10431 - Phosphoric acid esters (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphoric acid esters (generic). 721... Substances § 721.10431 Phosphoric acid esters (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as phosphoric acid esters (PMNs...

  6. 40 CFR 721.1732 - Nitrobenzoic acid octyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Nitrobenzoic acid octyl ester. 721... Substances § 721.1732 Nitrobenzoic acid octyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as nitrobenzoic acid octyl ester (PMN...

  7. 40 CFR 721.4158 - Hexadecanoic acid, ethenyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Hexadecanoic acid, ethenyl ester. 721... Substances § 721.4158 Hexadecanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexadecanoic acid, ethenyl ester (PMN...

  8. 40 CFR 721.1732 - Nitrobenzoic acid octyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Nitrobenzoic acid octyl ester. 721... Substances § 721.1732 Nitrobenzoic acid octyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as nitrobenzoic acid octyl ester (PMN...

  9. 40 CFR 721.5310 - Neononanoic acid, ethenyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Neononanoic acid, ethenyl ester. 721... Substances § 721.5310 Neononanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as neononanoic acid, ethenyl ester (PMN...

  10. 40 CFR 721.4158 - Hexadecanoic acid, ethenyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Hexadecanoic acid, ethenyl ester. 721... Substances § 721.4158 Hexadecanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexadecanoic acid, ethenyl ester (PMN...

  11. 40 CFR 721.4215 - Hexanedioic acid, diethenyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Hexanedioic acid, diethenyl ester. 721... Substances § 721.4215 Hexanedioic acid, diethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexanedioic acid, diethenyl ester (PMN...

  12. 40 CFR 721.1732 - Nitrobenzoic acid octyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Nitrobenzoic acid octyl ester. 721... Substances § 721.1732 Nitrobenzoic acid octyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as nitrobenzoic acid octyl ester (PMN...

  13. 40 CFR 721.1732 - Nitrobenzoic acid octyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Nitrobenzoic acid octyl ester. 721... Substances § 721.1732 Nitrobenzoic acid octyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as nitrobenzoic acid octyl ester (PMN...

  14. 40 CFR 721.10537 - Acrylate ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylate ester (generic). 721.10537... Substances § 721.10537 Acrylate ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylate ester (PMN P-01-579) is subject...

  15. 40 CFR 721.2121 - Thiosubstituted carbonate ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Thiosubstituted carbonate ester... Specific Chemical Substances § 721.2121 Thiosubstituted carbonate ester (generic). (a) Chemical substance... Thiosubstituted carbonate ester (PMN P-99-0654) is subject to reporting under this section for the significant...

  16. 21 CFR 556.240 - Estradiol and related esters.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Estradiol and related esters. 556.240 Section 556... Tolerances for Residues of New Animal Drugs § 556.240 Estradiol and related esters. No residues of estradiol, resulting from the use of estradiol or any of the related esters, are permitted in excess of the...

  17. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under...

  18. 21 CFR 556.240 - Estradiol and related esters.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Estradiol and related esters. 556.240 Section 556... Tolerances for Residues of New Animal Drugs § 556.240 Estradiol and related esters. No residues of estradiol, resulting from the use of estradiol or any of the related esters, are permitted in excess of the...

  19. 40 CFR 721.10431 - Phosphoric acid esters (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid esters (generic). 721... Substances § 721.10431 Phosphoric acid esters (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as phosphoric acid esters (PMNs...

  20. 40 CFR 721.2925 - Brominated aromatic ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Brominated aromatic ester. 721.2925... Substances § 721.2925 Brominated aromatic ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated aromatic ester (PMN...

  1. 40 CFR 721.1732 - Nitrobenzoic acid octyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Nitrobenzoic acid octyl ester. 721... Substances § 721.1732 Nitrobenzoic acid octyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as nitrobenzoic acid octyl ester (PMN...

  2. 40 CFR 721.2121 - Thiosubstituted carbonate ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Thiosubstituted carbonate ester... Specific Chemical Substances § 721.2121 Thiosubstituted carbonate ester (generic). (a) Chemical substance... Thiosubstituted carbonate ester (PMN P-99-0654) is subject to reporting under this section for the significant...

  3. 40 CFR 721.10477 - Acrylate ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylate ester (generic). 721.10477... Substances § 721.10477 Acrylate ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylate ester (PMN P-04-290) is subject...

  4. 40 CFR 721.10305 - Modified cyclohexane esters (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Modified cyclohexane esters (generic... Specific Chemical Substances § 721.10305 Modified cyclohexane esters (generic). (a) Chemical substance and... cyclohexane esters (PMN P-00-1108) is subject to reporting under this section for the significant new...

  5. 40 CFR 721.10477 - Acrylate ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acrylate ester (generic). 721.10477... Substances § 721.10477 Acrylate ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylate ester (PMN P-04-290) is subject...

  6. 40 CFR 721.10314 - Dialkyl dithiocarbamate esters (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Dialkyl dithiocarbamate esters... Specific Chemical Substances § 721.10314 Dialkyl dithiocarbamate esters (generic). (a) Chemical substance... dialkyl dithiocarbamate esters (PMNs P-02-778, P-02-779, and P-02-780) are subject to reporting under...

  7. 40 CFR 721.10438 - Dialkyl hydroxybenzenealkanoic acid ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester (generic). 721.10438 Section 721.10438 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10438 Dialkyl hydroxybenzenealkanoic acid ester (generic). (a) Chemical... as dialkyl hydroxybenzenealkanoic acid ester (PMN P-00-346) is subject to reporting under...

  8. 40 CFR 721.4158 - Hexadecanoic acid, ethenyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hexadecanoic acid, ethenyl ester. 721... Substances § 721.4158 Hexadecanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexadecanoic acid, ethenyl ester (PMN...

  9. 40 CFR 721.10537 - Acrylate ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acrylate ester (generic). 721.10537... Substances § 721.10537 Acrylate ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylate ester (PMN P-01-579) is subject...

  10. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under...

  11. 40 CFR 721.2925 - Brominated aromatic ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated aromatic ester. 721.2925... Substances § 721.2925 Brominated aromatic ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated aromatic ester (PMN...

  12. 21 CFR 172.735 - Glycerol ester of rosin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Glycerol ester of rosin. 172.735 Section 172.735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD....735 Glycerol ester of rosin. Glycerol ester of wood rosin, gum rosin, or tall oil rosin may be...

  13. 40 CFR 721.2121 - Thiosubstituted carbonate ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Thiosubstituted carbonate ester... Specific Chemical Substances § 721.2121 Thiosubstituted carbonate ester (generic). (a) Chemical substance... Thiosubstituted carbonate ester (PMN P-99-0654) is subject to reporting under this section for the significant...

  14. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under...

  15. 21 CFR 556.240 - Estradiol and related esters.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Estradiol and related esters. 556.240 Section 556... Tolerances for Residues of New Animal Drugs § 556.240 Estradiol and related esters. No residues of estradiol, resulting from the use of estradiol or any of the related esters, are permitted in excess of the...

  16. 40 CFR 721.2925 - Brominated aromatic ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Brominated aromatic ester. 721.2925... Substances § 721.2925 Brominated aromatic ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated aromatic ester (PMN...

  17. 40 CFR 721.2925 - Brominated aromatic ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Brominated aromatic ester. 721.2925... Substances § 721.2925 Brominated aromatic ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated aromatic ester (PMN...

  18. 40 CFR 721.2925 - Brominated aromatic ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Brominated aromatic ester. 721.2925... Substances § 721.2925 Brominated aromatic ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a brominated aromatic ester (PMN...

  19. 40 CFR 721.4158 - Hexadecanoic acid, ethenyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hexadecanoic acid, ethenyl ester. 721... Substances § 721.4158 Hexadecanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexadecanoic acid, ethenyl ester (PMN...

  20. 40 CFR 721.10685 - Phosphoric acid, mixed esters (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid, mixed esters (generic... Specific Chemical Substances § 721.10685 Phosphoric acid, mixed esters (generic). (a) Chemical substance... phosphoric acid, mixed esters (PMN P-13-170) is subject to reporting under this section for the...

  1. 40 CFR 721.10305 - Modified cyclohexane esters (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Modified cyclohexane esters (generic... Specific Chemical Substances § 721.10305 Modified cyclohexane esters (generic). (a) Chemical substance and... cyclohexane esters (PMN P-00-1108) is subject to reporting under this section for the significant new...

  2. 40 CFR 721.10314 - Dialkyl dithiocarbamate esters (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Dialkyl dithiocarbamate esters... Specific Chemical Substances § 721.10314 Dialkyl dithiocarbamate esters (generic). (a) Chemical substance... dialkyl dithiocarbamate esters (PMNs P-02-778, P-02-779, and P-02-780) are subject to reporting under...

  3. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under...

  4. 40 CFR 721.2121 - Thiosubstituted carbonate ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Thiosubstituted carbonate ester... Specific Chemical Substances § 721.2121 Thiosubstituted carbonate ester (generic). (a) Chemical substance... Thiosubstituted carbonate ester (PMN P-99-0654) is subject to reporting under this section for the significant...

  5. 40 CFR 721.10560 - Alkanoldioic dialkyl esters (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkanoldioic dialkyl esters (generic... Specific Chemical Substances § 721.10560 Alkanoldioic dialkyl esters (generic). (a) Chemical substance and... dialkyl esters (PMNs P-07-143 and P-07-144) are subject to reporting under this section for...

  6. 21 CFR 556.240 - Estradiol and related esters.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Estradiol and related esters. 556.240 Section 556... Tolerances for Residues of New Animal Drugs § 556.240 Estradiol and related esters. No residues of estradiol, resulting from the use of estradiol or any of the related esters, are permitted in excess of the...

  7. 40 CFR 721.10314 - Dialkyl dithiocarbamate esters (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Dialkyl dithiocarbamate esters... Specific Chemical Substances § 721.10314 Dialkyl dithiocarbamate esters (generic). (a) Chemical substance... dialkyl dithiocarbamate esters (PMNs P-02-778, P-02-779, and P-02-780) are subject to reporting under...

  8. 40 CFR 721.10715 - Carbonic acid, dialkyl ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Carbonic acid, dialkyl ester (generic... Specific Chemical Substances § 721.10715 Carbonic acid, dialkyl ester (generic). (a) Chemical substance and..., dialkyl ester (PMN P-13-346) is subject to reporting under this section for the significant new...

  9. 40 CFR 721.3140 - Vinyl epoxy ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Vinyl epoxy ester. 721.3140 Section... Substances § 721.3140 Vinyl epoxy ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance vinyl epoxy ester (PMN P-85-527) is subject to reporting under...

  10. 40 CFR 721.10560 - Alkanoldioic dialkyl esters (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkanoldioic dialkyl esters (generic... Specific Chemical Substances § 721.10560 Alkanoldioic dialkyl esters (generic). (a) Chemical substance and... dialkyl esters (PMNs P-07-143 and P-07-144) are subject to reporting under this section for...

  11. 40 CFR 721.2121 - Thiosubstituted carbonate ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Thiosubstituted carbonate ester... Specific Chemical Substances § 721.2121 Thiosubstituted carbonate ester (generic). (a) Chemical substance... Thiosubstituted carbonate ester (PMN P-99-0654) is subject to reporting under this section for the significant...

  12. 21 CFR 172.735 - Glycerol ester of rosin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Glycerol ester of rosin. 172.735 Section 172.735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... CONSUMPTION Other Specific Usage Additives § 172.735 Glycerol ester of rosin. Glycerol ester of wood...

  13. 40 CFR 721.10305 - Modified cyclohexane esters (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Modified cyclohexane esters (generic... Specific Chemical Substances § 721.10305 Modified cyclohexane esters (generic). (a) Chemical substance and... cyclohexane esters (PMN P-00-1108) is subject to reporting under this section for the significant new...

  14. 40 CFR 721.4158 - Hexadecanoic acid, ethenyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Hexadecanoic acid, ethenyl ester. 721... Substances § 721.4158 Hexadecanoic acid, ethenyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as hexadecanoic acid, ethenyl ester (PMN...

  15. 40 CFR 721.10438 - Dialkyl hydroxybenzenealkanoic acid ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ester (generic). 721.10438 Section 721.10438 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10438 Dialkyl hydroxybenzenealkanoic acid ester (generic). (a) Chemical... as dialkyl hydroxybenzenealkanoic acid ester (PMN P-00-346) is subject to reporting under...

  16. 21 CFR 172.735 - Glycerol ester of rosin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Glycerol ester of rosin. 172.735 Section 172.735 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... CONSUMPTION Other Specific Usage Additives § 172.735 Glycerol ester of rosin. Glycerol ester of wood...

  17. 40 CFR 721.3085 - Brominated phthalate ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Brominated phthalate ester. 721.3085... Substances § 721.3085 Brominated phthalate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as brominated phthalate ester (PMN P-90-581)...

  18. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  19. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  20. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  1. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  2. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  3. Regioselective ester cleavage during the preparation of bisphosphonate methacrylate monomers

    PubMed Central

    Chougrani, Kamel; Niel, Gilles; Boutevin, Bernard

    2011-01-01

    Summary New functional monomers bearing a methacrylate, a bisphosphonate function and, for most, an internal carboxylate group, were prepared for incorporation into copolymers with adhesive or anticorrosive properties. Methanolysis of some trimethylsilyl bisphosphonate esters not only deprotects the desired bisphosphonate function but also regioselectively cleaves the alkyl ester function without affecting the methacrylate ester. PMID:21512600

  4. Updated defense display market assessment

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel D.; Hopper, Darrel G.

    1999-08-01

    This paper addresses the number, function and size of principal military displays and establishes a basis to determine the opportunities for technology insertion in the immediate future and into the next millennium. Principal military displays are defined as those occupying appreciable crewstation real-estate and/or those without which the platform could not carry out its intended mission. DoD 'office' applications are excluded from this study. The military displays market is specified by such parameters as active area and footprint size, and other characteristics such as luminance, gray scale, resolution, angle, color, video capability, and night vision imaging system compatibility. Funded, future acquisitions, planned and predicted crewstation modification kits, and form-fit upgrades are taken into account. This paper provides an overview of the DoD niche market, allowing both government and industry a necessary reference by which to meet DoD requirements for military displays in a timely and cost-effective manner. The aggregate DoD installed base for direct-view and large-area military displays is presently estimated to be in excess of 313,000. Miniature displays are those which must be magnified to be viewed, involve a significantly different manufacturing paradigm and are used in helmet mounted displays and thermal weapon sight applications. Some 114,000 miniature displays are presently included within future weapon system acquisition plans. For vendor production planning purposes it is noted that foreign military sales could substantially increase these quantities. The vanishing vendor syndrome (VVS) for older display technologies continues to be a growing, pervasive problem throughout DoD, which consequently must leverage the more modern, especially flat panel, display technologies being developed to replace older, especially cathode ray tube, technology for civil-commercial markets. Total DoD display needs (FPD, HMD) are some 427,000.

  5. Insights on profiling of phorbol, deoxyphorbol, ingenol and jatrophane diterpene esters by high performance liquid chromatography coupled to multiple stage mass spectrometry.

    PubMed

    Nothias-Scaglia, Louis-Félix; Schmitz-Afonso, Isabelle; Renucci, Franck; Roussi, Fanny; Touboul, David; Costa, Jean; Litaudon, Marc; Paolini, Julien

    2015-11-27

    This paper reports our effort to develop a comprehensive HPLC-MS(n)-based dereplication strategy for phorbol ester (PE), deoxyphorbol ester (dPE) and ingenol ester (IE) profiling in plant extracts. This strategy is composed of two sequential analysis exploiting specific hybrid triple quadrupole/linear ion trap instrument modes. A first run was performed using a multiple reaction monitoring (MRM) mode targeting fragmentation of PE and dPE/IE coupled with the acquisition of MS(2) spectrum for the ions at m/z 311 and m/z 313, respectively. A second run was then completed based on precursor ion scan mode (PIS) and automatic MS(2) acquisition for each quasimolecular ion. The developed approach was used to investigate ten Euphorbia extracts showing bioactivity against chikungunya virus replication. Experiments allowed partial annotation of three dPE/IE but no PE was detected. Results suggested that other types of diterpene esters displayed PE- and dPE/IE-like fragmentations. The study of jatrophane ester (JE) standards by CID fragmentation using low and high resolution mass spectrometry confirmed this hypothesis, highlighting challenges and difficulties of diterpene esters profiling within plant extracts. Nonetheless, the present LC-MS(n) method can be easily adapted to profile other types of diterpene esters.

  6. Anti-inflammatory and anti-allergic activities of Pentaherb formula, Moutan Cortex (Danpi) and gallic acid.

    PubMed

    Liu, Kelly Y P; Hu, Shuiqing; Chan, Ben C L; Wat, Elaine C L; Lau, Clara B S; Hon, Kam L; Fung, Kwok P; Leung, Ping C; Hui, Patrick C L; Lam, Christopher W K; Wong, Chun K

    2013-01-01

    Pentaherb formula (PHF) has been proven to improve the quality of life of children with atopic dermatitis without side effects. The aim of this study was to elucidate the potential anti-inflammatory and anti-allergic activities of PHF, Moutan Cortex (Danpi/DP) and gallic acid (GA) using human basophils (KU812 cells), which are crucial effector cells in allergic inflammation. PHF, DP and GA could significantly suppress the expression of allergic inflammatory cytokine IL-33-upregulated intercellular adhesion molecule (ICAM)-1, and the release of chemokines CCL2, CCL5, CXCL8 and inflammatory cytokine IL-6 from KU812 cells (all p < 0.05). With the combined use of dexamethasone (0.01 μg/mL) and GA (10 μg/mL), the suppression of ICAM-1 expression and CCL5 and IL-6 release of IL-33-activated KU812 cells were significantly greater than the use of GA alone (all p < 0.05). The suppression of the IL-33-induced activation of intracellular signalling molecules p38 mitogen activated protein kinase, nuclear factor-kB and c-Jun amino-terminal kinase in GA-treated KU812 cells could be the underlying mechanism for the suppression on ICAM-1, chemokines and cytokines. The combined use of dexamethasone with the natural products PHF or DP or GA might therefore enhance the development of a novel therapeutic modality for allergic inflammatory diseases with high potency and fewer side effects.

  7. Curcumin protects against gallic acid-induced oxidative stress, suppression of glutathione antioxidant defenses, hepatic and renal damage in rats.

    PubMed

    Abarikwu, Sunny O; Durojaiye, Mojisola; Alabi, Adenike; Asonye, Bede; Akiri, Oghenetega

    2016-01-01

    Curcumin (Cur) and gallic acid (Gal) are major food additives. Cur has well-known antioxidant properties, whereas Gal has both antioxidant and pro-oxidant effects. The present study investigated the effects of oral administration of Gal with or without Cur on antioxidant enzymes activities, glutathione (GSH) and the enzymes in its metabolism in rat liver in vivo and markers of tissue damage in the serum. Results showed that the increase in serum creatinine level, alkaline phosphatase and lactate dehydrogenase activities by Gal treatment were inhibited by combined administration of Gal and Cur. The decrease in GSH-peroxidase, GSH-S-transferase, superoxide dismutase and GSH-reductase activities by Gal treatment were inhibited when both Gal and Cur were administered together. The malondialdehyde concentration and catalase activity were significantly increased following administration of Gal but not when the administration of Gal was combined with Cur. Finally, the increase in GSH level was seen following administration of Cur alone or in combination with Gal but not with Gal alone. These results suggest that Gal might induce oxidative stress in the rat liver and affect renal function that can be inhibited by the combined administration of Gal and Cur. PMID:26707166

  8. Colour stabilities of sour cherry juice concentrates enhanced with gallic acid and various plant extracts during storage.

    PubMed

    Navruz, Ayşe; Türkyılmaz, Meltem; Özkan, Mehmet

    2016-04-15

    Gallic acid (GA) and pomegranate rind extract (PRE), cherry stem extract (CSE) and green tea extract (GTE) were added to sour cherry juice concentrates (SCJCs) to enhance the colour. Effects of these copigment sources on anthocyanins, colour and turbidity were investigated during storage at -20, 4 and 20°C for 110 days. Cyanidin-3-glucosylrutinoside (cyd-3-glu-rut, 75%) was the major anthocyanin, followed by cyanidin-3-rutinoside (cyd-3-rut, 23%) and cyanidin-3-sophoroside (cyd-3-soph, 2%). While GA (37-53%), PRE (27-77%) and GTE (44-119%) increased the stabilities of cyd-3-rut and cyd-3-glu-rut, CSE reduced (12-24%) the stabilities of all anthocyanins. Polymeric colour and turbidity values increased after the addition of all extracts and GA. The lowest turbidity value after 110 days of storage at 20°C was determined in the SCJC enhanced with PRE. We recommend the addition of PRE to SCJC for the enhancement of anthocyanin stability and colour intensity, and the reduction in turbidity. PMID:26616935

  9. Colour stabilities of sour cherry juice concentrates enhanced with gallic acid and various plant extracts during storage.

    PubMed

    Navruz, Ayşe; Türkyılmaz, Meltem; Özkan, Mehmet

    2016-04-15

    Gallic acid (GA) and pomegranate rind extract (PRE), cherry stem extract (CSE) and green tea extract (GTE) were added to sour cherry juice concentrates (SCJCs) to enhance the colour. Effects of these copigment sources on anthocyanins, colour and turbidity were investigated during storage at -20, 4 and 20°C for 110 days. Cyanidin-3-glucosylrutinoside (cyd-3-glu-rut, 75%) was the major anthocyanin, followed by cyanidin-3-rutinoside (cyd-3-rut, 23%) and cyanidin-3-sophoroside (cyd-3-soph, 2%). While GA (37-53%), PRE (27-77%) and GTE (44-119%) increased the stabilities of cyd-3-rut and cyd-3-glu-rut, CSE reduced (12-24%) the stabilities of all anthocyanins. Polymeric colour and turbidity values increased after the addition of all extracts and GA. The lowest turbidity value after 110 days of storage at 20°C was determined in the SCJC enhanced with PRE. We recommend the addition of PRE to SCJC for the enhancement of anthocyanin stability and colour intensity, and the reduction in turbidity.

  10. Impact of trolox, quercetin, genistein and gallic acid on the oxidative damage to myofibrillar proteins: the carbonylation pathway.

    PubMed

    Utrera, Mariana; Estévez, Mario

    2013-12-15

    The carbonylation pathway involves the oxidative deamination of lysine residues to yield a carbonyl compound (α-aminoadipic semialdehyde) that can be further oxidised to α-aminoadipic acid and form Schiff bases structures. The effect of trolox and other phenolic compounds (PhC) (namely genistein, quercetin and gallic acid) on the protein carbonylation pathway occurred during the oxidation of myofibrillar proteins (MP) catalysed by a Fe(3+)/H2O2 system was studied. Trolox and PhC can exert either antioxidant or pro-oxidant capacities depending on their concentration, the oxidation conditions and the target in proteins. In general, quercetin and genistein showed an antioxidant activity towards lipid oxidation and the carbonylation pathway at different concentrations under the analysed conditions. Plausible mechanisms for the antioxidant and pro-oxidant effects of trolox and PhC on MP are discussed. Further research is needed to shed light on the effect of PhC mixtures on both lipid and protein oxidation. PMID:23993577

  11. Histopathological Analysis from Gallic Acid Administration on Hippocampal Cell Density, Depression, and Anxiety Related Behaviors in A Trimethyltin Intoxication Model

    PubMed Central

    Moghadas, Marzieh; Edalatmanesh, Mohammad Amin; Robati, Reza

    2016-01-01

    Objective The present study investigated the effects of gallic acid (GA) administration on trimethyltin chloride (TMT) induced anxiety, depression, and hippocampal neurodegen- eration in rats. Materials and Methods In this experimental study, the rats received intraperitoneal (i.p.) injections of TMT (8 mg/kg). The animals received either GA (50, 100 and 150 mg/kg) or saline as the vehicle for 14 consecutive days. We measured depression and anxiety levels of the rats by conducting the behavioral tail suspension (TST), elevatedplusmaze (EPM), and novelty suppressed feeding (NSF) tests. Histological analyses were then used to de- termine the cell densities of different hippocampal subdivisions. The data were analyzed with ANOVA and Tukey’s post hoc test. Results GA administration ameliorated anxiety and depression in the behavioral tests. The cell densities in the CA1, CA2, CA3 and DG hippocampal subdivisionsfrom GA-treat- ed rats were higher than saline treated rats. Conclusion GA treatment against TMT-induced hippocampal degeneration altered cellular loss in the hippocampus and ameliorated the depression-anxiety state in rats. PMID:26862525

  12. Gallic acid exhibits risks of inducing muscular hemorrhagic liposis and cerebral hemorrhage--its action mechanism and preventive strategy.

    PubMed

    Hsieh, Chiu-Lan; Lin, Chien-Hong; Wang, Hui-Er; Peng, Chiung-Chi; Peng, Robert Y

    2015-02-01

    Gallic acid (3,4,5-trihydroxybenzoic acid) (GA) occurs in many plants. The adverse effects of GA are seldom cited. GA (6-14 μM) provoked the hemorrhagic liposis of the cervical muscles and intracranial hemorrhage. The cause of these pathological events and the method for prevention are still lacking. Using the chicken embryo model and some selected nutraceutics such as folate, glutathione (GSH), N-acetylcysteine, and vitamin E (Vit E), we carried out this study. Results revealed that the action mechanism of GA involved (i) inducing hypoxia with upregulated gene hif-1α and downregulated ratio vegf-r2/vegf-a, leading to dys-vascularization and myopathy; (ii) impairing cytochrome c oxidase; (iii) stimulating creatine kinase and lactate dehydrogenase release; (iv) eliciting carnitine accumulation and liposis via downregulating gene CPT1; (v) suppressing superoxide dismutase and stimulating NO, H2O2, and malondialdehyde; and (vi) depleting erythrocytic and tissue GSH, resulting in hemorrhage. When both Vit E and GSH were applied to the day 1 chicks, a better alleviation effect was revealed. Conclusively, GA potentially exhibits adverse effect by eliciting hemorrhagic liposis of cervical muscles and cerebral hemorrhage. Supplementation with GSH, Vit E, and N-acetylcysteine is able to ameliorate these adverse effects, warranting the importance of restricting the clinical phytotherapeutic doses of GA and related compounds.

  13. Surface functionalization of bioactive glasses with natural molecules of biological significance, Part I: Gallic acid as model molecule

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Ferraris, Sara; Prenesti, Enrico; Verné, Enrica

    2013-12-01

    Gallic acid (3,4,5-trihydroxybenzoic acid, GA) and its derivatives are a group of biomolecules (polyphenols) obtained from plants. They have effects which are potentially beneficial to heath, for example they are antioxidant, anticarcinogenic and antibacterial, as recently investigated in many fields such as medicine, food and plant sciences. The main drawbacks of these molecules are both low stability and bioavailability. In this research work the opportunity to graft GA to bioactive glasses is investigated, in order to deliver the undamaged biological molecule into the body, using the biomaterial surfaces as a localized carrier. GA was considered for functionalization since it is a good model molecule for polyphenols and presents several interesting biological activities, like antibacterial, antioxidant and anticarcinogenic properties. Two different silica based bioactive glasses (SCNA and CEL2), with different reactivity, were employed as substrates. UV photometry combined with the Folin&Ciocalteu reagent was adopted to test the concentration of GA in uptake solution after functionalization. This test verified how much GA consumption occurred with surface modification and it was also used on solid samples to test the presence of GA on functionalized glasses. XPS and SEM-EDS techniques were employed to characterize the modification of material surface properties and functional group composition before and after functionalization.

  14. Hydrophilic gallic acid-imprinted polymers over magnetic mesoporous silica microspheres with excellent molecular recognition ability in aqueous fruit juices.

    PubMed

    Hu, Xin; Xie, Lianwu; Guo, Junfang; Li, Hui; Jiang, Xinyu; Zhang, Yuping; Shi, Shuyun

    2015-07-15

    Hydrophilic molecularly imprinted polymers (MIPs) for gallic acid (GA) were prepared with excellent recognition ability in an aqueous solution. The proposed MIPs were designed by self-polymerization of dopamine (DA) on magnetic mesoporous silica (Fe3O4@SiO2@mSiO2, MMS) using GA as template. Resulting Fe3O4@SiO2@mSiO2@MIPs (MMS-MIPs) were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM), and evaluated by adsorption isotherms/kinetics and competitive adsorption. The adsorption behavior between GA and MMS-MIPs followed Langmuir and Sips adsorption isotherms with a maximum adsorption capacity at 88.7 mg/g and pseudo-second-order reaction kinetics with fast binding (equilibrium time at 100 min). In addition, MMS-MIPs showed rapid magnetic separation (10 s) and stability (retained 95.2% after six cycles). Subsequently, MMS-MIPs were applied for the selective extraction and determination of GA from grape, apple, peach and orange juices (4.02, 3.91, 5.97, and 0.67 μg/g, respectively). Generally, the described method may pave the way towards rationally designing more advanced hydrophilic MIPs.

  15. Gallic acid-grafted chitooligosaccharides suppress antigen-induced allergic reactions in RBL-2H3 mast cells.

    PubMed

    Vo, Thanh-Sang; Ngo, Dai-Hung; Kim, Se-Kwon

    2012-09-29

    In this study, a bioactive derivative of chitooligosaccharides (3-5 kDa) was synthesized via grafting of gallic acid onto chitooligosaccharides (G-COS) to enhance anti-allergic activity. Hence, G-COS was evaluated for its capabilities against allergic reactions in RBL-2H3 mast cells sensitized with dinitrophenyl-specific immunoglobulin E antibody and stimulated by antigen dinitrophenyl-bovine serum albumin. It was revealed that G-COS exhibited significant inhibition on histamine release and production as well as intracellular Ca(2+) elevation at the concentration of 200μg/ml. Likewise, the suppressive effects of G-COS on expression and production of interleukin (IL)-4 and tumor necrosis factor (TNF)-α were evidenced. Moreover, G-COS treatment caused a remarkable blockade on degradation of inhibitory κB-α (IκB-α) protein, translocation of nuclear factor (NF)-κB, and phosphorylation of mitogen-activated protein kinases (MAPKs). Notably, the inhibitory activities of G-COS on allergic reactions were found as a consequence of suppression of FcεRI expression in antigen-stimulated cells. Accordingly, G-COS was suggested to be a promising candidate of novel inhibitors against allergic reactions.

  16. Effect of dietary supplementation of gallic acid on nitrogen balance, nitrogen excretion pattern and urinary nitrogenous constituents in beef cattle.

    PubMed

    Wei, Chen; Yang, Kai; Zhao, Guangyong; Lin, Shixin; Xu, Zhiwei

    2016-10-01

    The objective of the trial was to study the effects of dietary supplementation of gallic acid (GA) on nitrogen (N) balance, N excretion pattern and urinary N constituents in beef cattle. In a 4 × 4 Latin square design, four male 30-month-old Simmental cattle (443 ± 22 kg live weight) received four levels of GA (purity ≥ 98.5%), i.e. 0, 5.3, 10.5, 21.1 g/kg DM, added to a basal ration. Each experimental period lasted 17 d, consisting of 12 d adaptation and 5 d sampling. The results showed that supplementation of GA at 5.3, 10.5 or 21.1 g/kg DM did not affect the N balance but regulated the N excretion pattern by increasing the ratio of faecal N/urinary N and decreasing the ratio of urinary urea N/total urinary N in beef cattle fed at maintenance level. PMID:27494638

  17. Gallic acid as a selective anticancer agent that induces apoptosis in SMMC-7721 human hepatocellular carcinoma cells

    PubMed Central

    SUN, GUOJUN; ZHANG, SHUQIN; XIE, YANRU; ZHANG, ZIYU; ZHAO, WENJING

    2016-01-01

    Gallic acid (3,4,5-trihydroxybenzoic acid; GA) is a naturally occurring plant polyphenol, isolated from water caltrop, which has been reported to exert anticancer effects. The present study investigated the antiproliferative effects of GA on the HepG2 and SMMC-7721 human hepatocellular carcinoma (HCC) cell lines using MTT and colony formation assays. In particular, the underlying mechanism of GA-induced apoptosis in SMMC-7721 cells was studied in vitro by flow cytometry and western blotting. The results of the present study indicated that GA was capable of inhibiting the proliferation of HepG2 and SMMC-7721 cells in a time- and dose-dependent manner, as well as inducing the apoptosis of SMMC-7721 cells. GA induced caspase-3, caspase-9 and reactive oxygen species activity, elevated the expression of apoptosis regulator Bcl-2-like protein 4 and reduced the mitochondrial membrane potential in SMMC-7721 cells. When compared with HL-7702 normal human hepatocytes, GA demonstrated selective toxicity for HCC cells. In conclusion, GA is able to induce apoptosis in SMMC-7721 cells in vitro via mitochondrial-mediated pathways, and may possess the potential to be a novel therapeutic compound for use in the treatment of HCC. PMID:26870182

  18. Anticancer effects of gallic acid isolated from Indonesian herbal medicine, Phaleria macrocarpa (Scheff.) Boerl, on human cancer cell lines.

    PubMed

    Faried, A; Kurnia, D; Faried, L S; Usman, N; Miyazaki, T; Kato, H; Kuwano, H

    2007-03-01

    The natural antioxidant gallic acid (GA) was isolated from fruits of a medicinal Indonesian plant, Phaleria macrocarpa (Scheff.) Boerl. The structure was identified on the basis of spectroscopic analysis and comparison with authentic compound. GA demonstrated a significant inhibition of cell proliferation in a series of cancer cell lines and induced apoptosis in esophageal cancer cells (TE-2) but not in non-cancerous cells (CHEK-1). Observation of the molecular mechanism of apoptosis showed that GA up-regulated the pro-apoptosis protein, Bax, and induced caspase-cascade activity in cancer cells. On the other hand, GA down-regulated anti-apoptosis proteins such as Bcl-2 and Xiap. In addition, GA also induced down-regulation of the survival Akt/mTOR pathway. In non-cancerous cells, we observed delayed expression of pro-apoptosis related proteins. Our results suggest that GA might be a potential anticancer compound. However, in depth in vivo studies are needed to elucidate the exact mechanism. PMID:17273761

  19. Tunicate-Inspired Gallic Acid/Metal Ion Complex for Instant and Efficient Treatment of Dentin Hypersensitivity.

    PubMed

    Prajatelistia, Ekavianty; Ju, Sung-Won; Sanandiya, Naresh D; Jun, Sang Ho; Ahn, Jin-Soo; Hwang, Dong Soo

    2016-04-20

    Dentin hypersensitivity is sharp and unpleasant pains caused by exposed dentinal tubules when enamel outside of the tooth wears away. The occlusion of dentinal tubules via in situ remineralization of hydroxyapatite is the best method to alleviate the symptoms caused by dentin hypersensitivity. Commercially available dental desensitizers are generally effective only on a specific area and are relatively toxic, and their performance usually depends on the skill of the clinician. Here, a facile and efficient dentin hypersensitivity treatment with remarkable aesthetic improvement inspired by the tunicate-self-healing process is reported. As pyrogallol groups in tunicate proteins conjugate with metal ions to heal the torn body armor of a tunicate, the ingenious mechanism by introducing gallic acid (GA) as a cheap, abundant, and edible alternative to the pyrogallol groups of the tunicate combined with a varied daily intake of metal ion sources is mimicked. In particular, the GA/Fe(3+) complex exhibits the most promising results, to the instant ≈52% blockage in tubules within 4 min and ≈87% after 7 d of immersion in artificial saliva. Overall, the GA/metal ion complex-mediated coating is facile, instant, and effective, and is suggested as an aesthetic solution for treating dentin hypersensitivity. PMID:26867019

  20. Transport of Corilagin, Gallic Acid, and Ellagic Acid from Fructus Phyllanthi Tannin Fraction in Caco-2 Cell Monolayers

    PubMed Central

    Zhao, Hai-juan; Liang, Wen-Yi; Chen, Wen-Jing; Han, Shu-Xian; Qi, Qi; Cui, Ya-Ping; Li, Shi; Yang, Guang-Hui; Shao, Yan-Yan; Zhu, Dan

    2016-01-01

    Objective. To investigate the absorption property of the representative hydrolyzable tannin, namely corilagin, and its hydrolysates gallic acid (GA) and ellagic acid (EA) from the Fructus Phyllanthi tannin fraction (PTF) in vitro. Methods. Caco-2 cells monolayer model was established. Influences of PTF on Caco-2 cells viability were detected with MTT assay. The transport across monolayers was examined for different time points, concentrations, and secretory directions. The inhibitors of P-glycoprotein (P-gp), multidrug resistance proteins (MRPs), organic anion transporting polypeptide (OATP) and sodium/glucose cotransporter 1 (SGLT1), and tight junction modulators were used to study the transport mechanism. LC-MS method was employed to quantify the absorption concentration. Results. The apparent permeability coefficient (Papp) values of the three compounds were below 1.0 × 10−6 cm/s. The absorption of corilagin and GA were much lower than their efflux, and the uptake of both compounds was increased in the presence of inhibitors of P-gp and MRPs. The absorption of EA was decreased in the company of OATP and SGLT1 inhibitors. Moreover, the transport of corilagin, GA, and EA was enhanced by tight junction modulators. Conclusion. These observations indicated that the three compounds in PTF were transported via passive diffusion combined with protein mediated transport. P-gp and MRPs might get involved in the transport of corilagin and GA. The absorption of EA could be attributed to OATP and SGLT1 protein. PMID:27738446

  1. Microcultures of lactic acid bacteria: characterization and selection of strains, optimization of nutrients and gallic acid concentration.

    PubMed

    Guzmán-López, Oswaldo; Loera, Octavio; Parada, José Luis; Castillo-Morales, Alberto; Martínez-Ramírez, Cándida; Augur, Christopher; Gaime-Perraud, Isabelle; Saucedo-Castañeda, Gerardo

    2009-01-01

    Eighteen lactic acid bacteria (LAB) strains, isolated from coffee pulp silages were characterized according to both growth and gallic acid (GA) consumption. Prussian blue method was adapted to 96-well microplates to quantify GA in LAB microcultures. Normalized data of growth and GA consumption were used to characterize strains into four phenotypes. A number of 5 LAB strains showed more than 60% of tolerance to GA at 2 g/l; whereas at 10 g/l GA growth inhibition was detected to a different extent depending on each strain, although GA consumption was observed in seven studied strains (>60%). Lactobacillus plantarum L-08 was selected for further studies based on its capacity to degrade GA at 10 g/l (97%). MRS broth and GA concentrations were varied to study the effect on growth of LAB. Cell density and growth rate were optimized by response surface methodology and kinetic analysis. Maximum growth was attained after 7.5 h of cultivation, with a dilution factor of 1-1/2 and a GA concentration between 0.625 and 2.5 g/l. Results indicated that the main factor affecting LAB growth was GA concentration. The main contribution of this study was to propose a novel adaptation of a methodology to characterize and select LAB strains with detoxifying potential of simple phenolics based on GA consumption and tolerance. In addition, the methodology presented in this study integrated the well-known RSM with an experimental design based on successive dilutions.

  2. Synthesis of 11C labelled methyl esters: transesterification of enol esters versus BF 3 catalysed esterification—a comparative study

    NASA Astrophysics Data System (ADS)

    Ackermann, Uwe; Blanc, Paul; Falzon, Cheryl L.; Issa, William; White, Jonathan; Tochon-Danguy, Henri J.; Sachinidis, John I.; Scott, Andrew M.

    2006-01-01

    C-11 labelled methyl esters have been synthesized via the transesterification of enol esters in the presence of C-11 methanol and 1,3 dichlorodibutylstannoxane as catalyst. This method leaves functional groups intact and allows access to a wider variety of C-11 labelled methyl esters compared to the BF 3 catalysed ester formation, which uses carboxylic acids and C-11 methanol as starting materials.

  3. In Vitro Sustained Release Study of Gallic Acid Coated with Magnetite-PEG and Magnetite-PVA for Drug Delivery System

    PubMed Central

    Kura, Aminu Umar; Hussein-Al-Ali, Samer Hasan; Bin Hussein, Mohd Zobir; Fakurazi, Sharida; Shaari, Abdul Halim; Ahmad, Zalinah

    2014-01-01

    The efficacy of two nanocarriers polyethylene glycol and polyvinyl alcohol magnetic nanoparticles coated with gallic acid (GA) was accomplished via X-ray diffraction, infrared spectroscopy, magnetic measurements, thermal analysis, and TEM. X-ray diffraction and TEM results showed that Fe3O4 nanoparticles were pure iron oxide having spherical shape with the average diameter of 9 nm, compared with 31 nm and 35 nm after coating with polyethylene glycol-GA (FPEGG) and polyvinyl alcohol-GA (FPVAG), respectively. Thermogravimetric analyses proved that after coating the thermal stability was markedly enhanced. Magnetic measurements and Fourier transform infrared (FTIR) revealed that superparamagnetic iron oxide nanoparticles could be successfully coated with two polymers (PEG and PVA) and gallic acid as an active drug. Release behavior of gallic acid from two nanocomposites showed that FPEGG and FPVAG nanocomposites were found to be sustained and governed by pseudo-second-order kinetics. Anticancer activity of the two nanocomposites shows that the FPEGG demonstrated higher anticancer effect on the breast cancer cell lines in almost all concentrations tested compared to FPVAG. PMID:24737969

  4. In Vitro Antioxidant-Activity Evaluation of Gallic-Acid-Grafted Chitosan Conjugate Synthesized by Free-Radical-Induced Grafting Method.

    PubMed

    Hu, Qiaobin; Wang, Taoran; Zhou, Mingyong; Xue, Jingyi; Luo, Yangchao

    2016-07-27

    The major objective of this work was to develop a green and facile process to prepare gallic acid-chitosan conjugate and comprehensively evaluate the physicochemical properties and biological activities of an as-prepared water-soluble chitosan derivative. A free-radical-induced grafting approach using an ascorbic acid-hydrogen peroxide redox pair was adopted. The obtained conjugate was characterized by Fourier transform infrared spectroscopy, UV-vis, X-ray diffraction, and pKa analysis. The antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6)-sulphonic acid (ABTS), reducing power, and oxygen-radical antioxidant-capacity assays. The results showed that the mass ratio of gallic acid to chitosan played a vital role in determining the grafting degree and ζ potential of the conjugates, with the ratio of 0.5:1 being the optimal ratio that resulted in the highest grafting degree. The antioxidant assays demonstrated that conjugation significantly improved the antioxidant activities, being dramatically higher than that of free chitosan. It was notable that the DPPH- and ABTS-scavenging activities of conjugate at 0.4 mg/mL reached the same level as the free gallic acid at the equivalent concentration. Our study demonstrated a green and facile synthesis approach to preparing a novel water-soluble chitosan derivative that may have promising potentials in the food industry.

  5. Reversed-phase-liquid chromatography method for separation and quantification of gallic acid from hydroalcoholic extracts of Qualea grandiflora and Qualea parviflora

    PubMed Central

    de Mesquita, Mariana L.; Leão, Waleska F.; Ferreira, Magda R. A.; de Paula, José E.; Espindola, Laila S.; Soares, Luiz A. L.

    2015-01-01

    Background: Qualea parviflora and Qualea grandiflora (Vochysiaceae), commonly known in Brazil as “pau-terra” and “pau-terrinha,” respectively, have been widely used in the treatment of ulcer and gastritis. These therapeutic effects are attributed to various compounds present in the plants, including phenolic compounds such as gallic acid, due to their important antioxidant activity. Objective: The aim of the present study was to validate a high performance liquid chromatography with diode array detection (HPLC-DAD) method for the quantitative determination of gallic acid in the stem bark of Q. parviflora and Q. grandiflora hydroalcoholic extracts. Materials and Methods: The chromatography analysis was successfully achieved on a Dionex column, Acclaim® 120 (250 mm × 4.60 mm, 5 µm) with a gradient elution of water and methanol at a flow rate of 0.8 mL/min and ultraviolet detection at 280 nm. Results: The validation data, including linearity, precision, specificity, accuracy and robustness of this method demonstrated good reliability and sensitivity. Conclusion: The method is able to quantify gallic acid in the stem bark of both species. What is more, the chromatographic peaks showed good resolution and there are also the advantages of easy sample preparation and a short time between each injection. PMID:26664021

  6. Flexible Bistable Cholesteric Reflective Displays

    NASA Astrophysics Data System (ADS)

    Yang, Deng-Ke

    2006-03-01

    Cholesteric liquid crystals (ChLCs) exhibit two stable states at zero field condition-the reflecting planar state and the nonreflecting focal conic state. ChLCs are an excellent candidate for inexpensive and rugged electronic books and papers. This paper will review the display cell structure,materials and drive schemes for flexible bistable cholesteric (Ch) reflective displays.

  7. Displays: Entering a New Dimension

    ERIC Educational Resources Information Center

    Starkman, Neal

    2007-01-01

    As display technologies prepare to welcome 3-D, the 21st-century classroom will soon bear little resemblance to anything students and teachers have ever seen. In this article, the author presents the latest innovations in the world of digital display technology. These include: (1) Touchlight, an interactive touch screen program that takes a normal…

  8. Phorbol esters promote alpha 1-adrenergic receptor phosphorylation and receptor uncoupling from inositol phospholipid metabolism.

    PubMed Central

    Leeb-Lundberg, L M; Cotecchia, S; Lomasney, J W; DeBernardis, J F; Lefkowitz, R J; Caron, M G

    1985-01-01

    DDT1 MF-2 cells, which are derived from hamster vas deferens smooth muscle, contain alpha 1-adrenergic receptors (54,800 +/- 2700 sites per cell) that are coupled to stimulation of inositol phospholipid metabolism. Incubation of these cells with tumor-promoting phorbol esters, which stimulate calcium- and phospholipid-dependent protein kinase, leads to a marked attenuation of the ability of alpha 1-receptor agonists such as norepinephrine to stimulate the turnover of inositol phospholipids. This turnover was measured by determining the 32P content of phosphatidylinositol and phosphatidic acid after prelabeling of the cellular ATP pool with 32Pi. These phorbol ester-treated cells also displayed a decrease in binding affinity of cellular alpha 1 receptors for agonists with no change in antagonist affinity. By using affinity chromatography on the affinity resin Affi-Gel-A55414, the alpha 1 receptors were purified approximately equal to 300-fold from control and phorbol ester-treated 32Pi-prelabeled cells. As assessed by NaDodSO4/polyacrylamide gel electrophoresis, the Mr 80,000 alpha 1-receptor ligand-binding subunit is a phosphopeptide containing 1.2 mol of phosphate per mol of alpha 1 receptor. After phorbol ester treatment this increased to 3.6 mol of phosphate per mol of alpha 1 receptor. The effect of phorbol esters on norepinephrine-stimulated inositol phospholipid turnover and alpha 1-receptor phosphorylation showed the same rapid time course with a t1/2 less than 2 min. These results indicate that calcium- and phospholipid-dependent protein kinase may play an important role in regulating the function of receptors that are coupled to the inositol phospholipid cycle by phosphorylating and deactivating them. Images PMID:2994039

  9. Phenyl Esters Are Potent Inhibitors of Caseinolytic Protease P and Reveal a Stereogenic Switch for Deoligomerization.

    PubMed

    Hackl, Mathias W; Lakemeyer, Markus; Dahmen, Maria; Glaser, Manuel; Pahl, Axel; Lorenz-Baath, Katrin; Menzel, Thomas; Sievers, Sonja; Böttcher, Thomas; Antes, Iris; Waldmann, Herbert; Sieber, Stephan A

    2015-07-01

    Caseinolytic protease P (ClpP) represents a central bacterial degradation machinery that is involved in cell homeostasis and pathogenicity. The functional role of ClpP has been studied by genetic knockouts and through the use of beta-lactones, which remain the only specific inhibitors of ClpP discovered to date. Beta-lactones have served as chemical tools to manipulate ClpP in several organisms; however, their potency, selectivity and stability is limited. Despite detailed structural insights into the composition and conformational flexibility of the ClpP active site, no rational efforts to design specific non-beta-lactone inhibitors have been reported to date. In this work, an unbiased screen of more than 137 000 compounds was used to identify five phenyl ester compounds as highly potent ClpP inhibitors that were selective for bacterial, but not human ClpP. The potency of phenyl esters largely exceeded that of beta-lactones in ClpP peptidase and protease inhibition assays and displayed unique target selectivity in living S. aureus cells. Analytical studies revealed that while phenyl esters are cleaved like native peptide substrates, they remain covalently trapped as acyl-enzyme intermediates in the active site. The synthesis of 36 derivatives and subsequent structure-activity relationship (SAR) studies provided insights into conserved structural elements that are important for inhibition potency and acylation reactivity. Moreover, the stereochemistry of a methyl-substituent at the alpha position to the ester, resembling amino acid side chains in peptide substrates, impacted ClpP complex stability, causing either dissociation into heptamers or retention of the tetradecameric state. Mechanistic insights into this intriguing stereo switch and the phenyl ester binding mode were obtained by molecular docking experiments.

  10. Drugs derived from phage display

    PubMed Central

    Nixon, Andrew E; Sexton, Daniel J; Ladner, Robert C

    2014-01-01

    Phage display, one of today’s fundamental drug discovery technologies, allows identification of a broad range of biological drugs, including peptides, antibodies and other proteins, with the ability to tailor critical characteristics such as potency, specificity and cross-species binding. Further, unlike in vivo technologies, generating phage display-derived antibodies is not restricted by immunological tolerance. Although more than 20 phage display-derived antibody and peptides are currently in late-stage clinical trials or approved, there is little literature addressing the specific challenges and successes in the clinical development of phage-derived drugs. This review uses case studies, from candidate identification through clinical development, to illustrate the utility of phage display as a drug discovery tool, and offers a perspective for future developments of phage display technology. PMID:24262785

  11. INFORMATION DISPLAY: CONSIDERATIONS FOR DESIGNING COMPUTER-BASED DISPLAY SYSTEMS.

    SciTech Connect

    O'HARA,J.M.; PIRUS,D.; BELTRATCCHI,L.

    2004-09-19

    This paper discussed the presentation of information in computer-based control rooms. Issues associated with the typical displays currently in use are discussed. It is concluded that these displays should be augmented with new displays designed to better meet the information needs of plant personnel and to minimize the need for interface management tasks (the activities personnel have to do to access and organize the information they need). Several approaches to information design are discussed, specifically addressing: (1) monitoring, detection, and situation assessment; (2) routine task performance; and (3) teamwork, crew coordination, collaborative work.

  12. Plant Natural Products Calycosin and Gallic Acid Synergistically Attenuate Neutrophil Infiltration and Subsequent Injury in Isoproterenol-Induced Myocardial Infarction: A Possible Role for Leukotriene B4 12-Hydroxydehydrogenase?

    PubMed

    Cheng, Yuanyuan; Zhao, Jia; Tse, Hung Fat; Le, X Chris; Rong, Jianhui

    2015-01-01

    Leukotriene B4 12-hydroxydehydrogenase (LTB4DH) catalyzes the oxidation of proinflammatory LTB4 into less bioactive 12-oxo-LTB4. We recently discovered that LTB4DH was induced by two different natural products in combination. We previously isolated gallic acid from Radix Paeoniae through a bioactivity-guided fractionation procedure. The purpose of this study is to test the hypothesis that LTB4DH inducers may suppress neutrophil-mediated inflammation in myocardial infarction. We first isolated the active compound(s) from another plant, Radix Astragali, by the similar strategy. By evaluating LTB4DH induction, we identified calycosin and formononetin from Radix Astragali by HPLC-ESI-MS technique. We confirmed that gallic acid and commercial calycosin or formononetin could synergistically induce LTB4DH expression in HepG2 cells and human neutrophils. Moreover, calycosin and gallic acid attenuated the effects of LTB4 on the survival and chemotaxis of neutrophil cell culture. We further demonstrated that calycosin and gallic acid synergistically suppressed neutrophil infiltration and protected cardiac integrity in the isoproterenol-induced mice model of myocardial infarction. Calycosin and gallic acid dramatically suppressed isoproterenol-induced increase in myeloperoxidase (MPO) activity and malondialdehyde (MDA) level. Collectively, our results suggest that LTB4DH inducers (i.e., calycosin and gallic acid) may be a novel combined therapy for the treatment of neutrophil-mediated myocardial injury.

  13. Aggregation behavior and antimicrobial activity of ester-functionalized imidazolium- and pyridinium-based ionic liquids in aqueous solution.

    PubMed

    Garcia, M Teresa; Ribosa, Isabel; Perez, Lourdes; Manresa, Angeles; Comelles, Francesc

    2013-02-26

    Two series of long chain imidazolium- and pyridinium-based ionic liquids containing an ester functional group in the alkyl side chain, 3-methyl-1-alkyloxycarbonylmethylimidazolium bromides (C(n)EMeImBr) and 1-alkyloxycarbonylmethylpyridinium bromides (C(n)EPyrBr), were synthesized and their thermal stability, aggregation behavior in aqueous medium, and antimicrobial activity investigated. The introduction of an ester group decreased the thermal stability of the functionalized ILs compared to simple alkyl chain containing ILs (1-alkyl-3-methylimidazolium bromides and 1-alkylpyridinium bromides). Tensiometry, conductimetry, and spectrofluorimetry were applied to study the self-aggregation of the amphiphilic ILs in aqueous solution. The ILs investigated displayed surface activity and the characteristic chain length dependence of the micellization process of surfactants. As compared to simple alkyl chain containing ILs bearing the same hydrocarbon chain, ester-functionalized ILs possess higher adsorption efficiency (pC(20)) and significantly lower critical micelle concentration (cmc) and surface tension at the cmc (γ(cmc)), indicating that the incorporation of an ester group promotes adsorption at the air/water interface and micelle formation. The antimicrobial activity was evaluated against Gram-negative and Gram-positive bacteria and fungi. ILs containing more than eight carbon atoms in the alkyl chain showed antimicrobial activity. Their efficiency as antimicrobial agents increased with the hydrophobicity of the amphiphilic cation being the C(12) homologous the most active compounds. The incorporation of an ester group particularly increased the biological activity against fungi.

  14. The peroxisome proliferator activated receptor delta is required for the differentiation of THP-1 monocytic cells by phorbol ester.

    PubMed

    Vosper, Helen; Khoudoli, Guennadi A; Palmer, Colin NA

    2003-12-11

    BACKGROUND: PPARdelta (NR1C2) promotes lipid accumulation in human macrophages in vitro and has been implicated in the response of macrophages to vLDL. We have investigated the role of PPARdelta in PMA-stimulated macrophage differentiation.The THP-1 monocytic cell line which displays macrophage like differentiation in response to phorbol esters was used as a model system. We manipulated the response to PMA using a potent synthetic agonist of PPARdelta, compound F. THP-1 sub-lines that either over-expressed PPARdelta protein, or expressed PPARdelta anti-sense RNA were generated. We then explored the effects of these genetic modulations on the differentiation process. RESULTS: The PPARdelta agonist, compound F, stimulated differentiation in the presence of sub-nanomolar concentrations of phorbol ester. Several markers of differentiation were induced by compound F in a synergistic fashion with phorbol ester, including CD68 and IL8. Over-expression of PPARdelta also sensitised THP-1 cells to phorbol ester and correspondingly, inhibition of PPARdelta by anti-sense RNA completely abolished this response. CONCLUSIONS: These data collectively demonstrate that PPARdelta plays a fundamental role in mediating a subset of cellular effects of phorbol ester and supports observations from mouse knockout models that PPARdelta is involved in macrophage-mediated inflammatory responses.

  15. Thermal properties and nanodispersion behavior of synthesized β-sitosteryl acyl esters: a structure-activity relationship study.

    PubMed

    Panpipat, Worawan; Dong, Mingdong; Xu, Xuebing; Guo, Zheng

    2013-10-01

    The efficiency (dose response) of cholesterol-lowering effect of phytosterols in humans depends on their chemical forms (derived or non-derived) and formulation methods in a delivery system. With a series of synthesized β-sitosteryl fatty acid esters (C2:0-C18:0 and C18:1-C18:3), this work examined their thermal properties and applications in preparation of nanodispersion with β-sitosterol as a comparison. Inspection of the melting point (Tm) and the heat of fusion (ΔH) of β-sitosteryl fatty acid esters and the chain length and unsaturation degree of fatty acyl moiety revealed a pronounced structure-property relationship. The nanodispersions prepared with β-sitosterol and β-sitosteryl saturated fatty acid (SFA) esters displayed different particle size distribution patterns (polymodal vs bimodal), mean diameter (115 nm vs less than 100 nm), and polydispersity index (PDI) (0.50 vs 0.23-0.38). β-sitosteryl unsaturated fatty acid (USFA) esters showed a distinctly different dispersion behavior to form nanoemulsions, rather than nanodispersions, with more homogeneous particle size distribution (monomodal, mean diameter 27-63 nm and PDI 0.18-0.25). The nanodispersion of β-sitosteryl medium chain SFA ester (C14:0) demonstrated a best storage stability.

  16. Effect of esters on lubricity of hydrotreated jet fuel

    SciTech Connect

    Kislenko, A.S.; Krylov, I.F.; Sokolova, G.I.; Vishnyakova, T.P.

    1985-07-01

    The authors synthesized a number of esters of stearic acid with polyhydric alcohols and ran comparative tests on aliphatic alcohols to determine their effects on the antiwear properties of the fuel. They conclude that the differences in effectiveness in improving the lubricity by the use of aliphatic alcohols and the full and partial esters of polyhydric alcohols and stearic acid can be explained by the presence of hydroxyl and ester groups close to each other in partial esters. This is reflected in the higher polarity of the partial esters, a higher rate of adsorption, and a stronger bonding of the adsorbed layer to the metal surface.

  17. Cockpit display requirements and specifications

    NASA Astrophysics Data System (ADS)

    Hopper, Darrel G.

    1993-12-01

    Flight instrument design has begun to include a new electronic technology for the display head: active matrix liquid crystal display (AMLCD). This is a significant design transition and applies across the board to complete cockpit modernization programs, individual instrument replacement projects, and new systems. AMLCD-based instruments are expected to have a substantially higher mean time between failure compared to both electromechanical and CRT- based instruments. Thus, the new technology will pay for itself. Furthermore, AMLCDs are truly sunlight-readable whereas CRT displays are not; it is mission critical that a pilot be able to see an instrument with the sun shining directly in the eye or onto the display. AMLCDs can also provide larger display areas enabling formats which increase situational awareness. As this is a new technology for the military, an industrial base for militarized AMLCDs must be created based on present research capabilities. The requirements for AMLCDs in DOD programs have been analyzed. Projects to build infrastructure and capacity are described. Applications include not only cockpits, but also digital map/GPS integrated displays for tank commanders and field laptop computers. We have the opportunity with this new technology to establish a common critical item product function specification for sunlight-readable, color and grayscale capable, flat panel displays for military applications. the Wright Laboratory is leading the development of such functional specification for U.S. military aircraft.

  18. Lizard threat display handicaps endurance.

    PubMed Central

    Brandt, Y

    2003-01-01

    Honest-signalling theory asserts that threat displays reliably advertise attributes that influence fighting success. Endurance, as measured by treadmill performance, predicts the outcome of agonistic interactions among lizards. If threat displays in lizards function to advertise endurance capacity then variation in threat displays should correlate with endurance. I tested this prediction for the duration of threat posturing in male side-blotched lizards (Uta stansburiana) and examined whether threat displays act as quality handicaps, reliable signals that expend the attribute that is advertised. Individual variation in the duration of threat posturing correlated with endurance, while an experimental reduction of endurance diminished the duration of threat posturing. As expected of a quality handicap, endurance fell below baseline after display production. A restriction of aerobic metabolism can account for this effect. In threat posturing, lateral compression of the thorax may interfere with respiration or with circulation, limiting aerobic metabolism and causing a compensatory increase in anaerobic metabolism, thereby generating lactate and diminishing locomotor capacity. Concentrations of lactate measured after display production were higher than baseline, consistent with the proposed mechanism. By restricting aerobic metabolism, the threat posture can act as a quality handicap, simultaneously advertising and expending the endurance capacity of displaying lizards. PMID:12803896

  19. Why do animals repeat displays?

    PubMed

    Payne; Pagel

    1997-07-01

    Both agonistic and sexual animal displays often involve more than one performance of some specific display action. Since repetition is energetically costly there must be good reasons why a signaller should carry out such repetitive actions, rather than simply displaying once. We briefly review three different 'reasons' which arise from three different receiver assessment rules: when assessment is based on the average magnitude of all display actions so far, the reason for the repetition is to improve the accuracy of the estimate (model A); when the assessment is based solely on the action of greatest magnitude so far, the repetition is to replace the signal with one of greater magnitude (model B); when the assessment is based on the cumulative sum of all display actions so far, the repetition is to augment that sum (model C). We discuss how to characterize each case from an understanding of its expected optimal behaviour as predicted by formal models. For model A the mean magnitude of display actions should stay constant and the contest duration should depend on relative qualities. In models B and C the encounter duration depends only on the weaker participant. In model B each display action is greater than the previous, but only a small number of steps are expected. In model C the magnitude of display actions can either escalate, stay constant, or even decrease. The displays of cichlid fish, the roaring contests of red deer, Cervus elaphusthe calling of Blanchard's cricket frogs, Acris crepitans blanchardiand the pheromonal exchanges of yeast gametes are used as illustrative examples.

  20. DARPA high resolution display technologies

    NASA Astrophysics Data System (ADS)

    Slusarczuk, Marko

    1990-11-01

    Much of the information of interest to pilots in flight is display-limited, and is undergoing substantial expansion due to improved sensor output and signal processing; attention is accordingly given to digitally-based instrument display imaging in the present evaluation of high-resolution cockpit display technologies. Also noted are the advantages of digitally transmitted sensor data in cases where the airborne reconnaissance user may be able to analyze telemetered airborne data in real time and respond with requests to the pilot for more detailed information of specific battlefield sites.

  1. Texture-Based Correspondence Display

    NASA Technical Reports Server (NTRS)

    Gerald-Yamasaki, Michael

    2004-01-01

    Texture-based correspondence display is a methodology to display corresponding data elements in visual representations of complex multidimensional, multivariate data. Texture is utilized as a persistent medium to contain a visual representation model and as a means to create multiple renditions of data where color is used to identify correspondence. Corresponding data elements are displayed over a variety of visual metaphors in a normal rendering process without adding extraneous linking metadata creation and maintenance. The effectiveness of visual representation for understanding data is extended to the expression of the visual representation model in texture.

  2. Antioxidant activity of phenolic compounds added to a functional emulsion containing omega-3 fatty acids and plant sterol esters.

    PubMed

    Espinosa, Raquel Rainho; Inchingolo, Raffaella; Alencar, Severino Matias; Rodriguez-Estrada, Maria Teresa; Castro, Inar Alves

    2015-09-01

    The effect of eleven compounds extracted from red propolis on the oxidative stability of a functional emulsion was evaluated. Emulsions prepared with Echium oil as omega 3 (ω-3 FA) source, containing 1.63 g/100mL of α-linolenic acid (ALA), 0.73 g/100 mL of stearidonic acid (SDA) and 0.65 g/100mL of plant sterol esters (PSE) were prepared without or with phenolic compounds (vanillic acid, caffeic acid, trans-cinnamic acid, 2,4-dihydroxycinnamic acid, p-coumaric acid, quercetin, trans-ferulic acid, trans,trans-farnesol, rutin, gallic acid or sinapic acid). tert-Butylhydroquinone and a mixture containing ascorbic acid and FeSO4 were applied as negative and positive controls of the oxidation. Hydroperoxide, thiobarbituric acid reactive substances (TBARS), malondialdehyde and phytosterol oxidation products (POPs) were evaluated as oxidative markers. Based on hydroperoxide and TBARS analysis, sinapic acid and rutin (200 ppm) showed the same antioxidant activity than TBHQ, representing a potential alternative as natural antioxidant to be applied in a functional emulsion containing ω-3 FA and PSE.

  3. Color speckle in laser displays

    NASA Astrophysics Data System (ADS)

    Kuroda, Kazuo

    2015-07-01

    At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

  4. Localization in virtual acoustic displays

    NASA Technical Reports Server (NTRS)

    Wenzel, Elizabeth M.

    1992-01-01

    This paper discusses the development of a particular spatial display medium, the virtual acoustic display. Although the technology can stand alone, it is envisioned ultimately to be a component of a larger multisensory environment and will no doubt find its greatest utility in that context. A general philosophy of the project has been that the development of advanced computer interfaces should be driven first by an understanding of human perceptual requirements, and secondarily by technological capabilities or constraints. In expanding on this view, the paper addresses why virtual acoustic displays are useful, characterizes the abilities of such displays, reviews some recent approaches to their implementation and application, describes the research project at NASA Ames in some detail, and finally outlines some critical research issues for the future.

  5. Multiplane binocular visual display system

    NASA Technical Reports Server (NTRS)

    Chase, W. D.

    1976-01-01

    Electro-optic system is interfaced with digital computer in flight simulator to generate simultaneous multiple-image planes in real time. System may have applications with other display and remote-control systems.

  6. Localization in virtual acoustic displays

    NASA Astrophysics Data System (ADS)

    Wenzel, Elizabeth M.

    This paper discusses the development of a particular spatial display medium, the virtual acoustic display. Although the technology can stand alone, it is envisioned ultimately to be a component of a larger multisensory environment and will no doubt find its greatest utility in that context. A general philosophy of the project has been that the development of advanced computer interfaces should be driven first by an understanding of human perceptual requirements, and secondarily by technological capabilities or constraints. In expanding on this view, the paper addresses why virtual acoustic displays are useful, characterizes the abilities of such displays, reviews some recent approaches to their implementation and application, describes the research project at NASA Ames in some detail, and finally outlines some critical research issues for the future.

  7. 10-inch planar optic display

    NASA Astrophysics Data System (ADS)

    Beiser, Leo; Veligdan, James T.

    1996-05-01

    A planar optic display (POD) is being built and tested for suitability as a high brightness replacement for the cathode ray tube, (CRT). The POD display technology utilizes a laminated optical waveguide structure which allows a projection type of display to be constructed in a thin (1 to 2 inch) housing. Inherent in the optical waveguide is a black cladding matrix which gives the display a black appearance leading to very high contrast. A digital micromirror device, (DMD) from Texas Instruments is used to create video images in conjunction with a 100 milliwatt green solid state laser. An anamorphic optical system is used to inject light into the POD to form a stigmatic image. In addition to the design of the POD screen, we discuss: image formation, image projection, and optical design constraints.

  8. Ten inch Planar Optic Display

    SciTech Connect

    Beiser, L.; Veligdan, J.

    1996-04-01

    A Planar Optic Display (POD) is being built and tested for suitability as a high brightness replacement for the cathode ray tube, (CRT). The POD display technology utilizes a laminated optical waveguide structure which allows a projection type of display to be constructed in a thin (I to 2 inch) housing. Inherent in the optical waveguide is a black cladding matrix which gives the display a black appearance leading to very high contrast. A Digital Micromirror Device, (DMD) from Texas Instruments is used to create video images in conjunction with a 100 milliwatt green solid state laser. An anamorphic optical system is used to inject light into the POD to form a stigmatic image. In addition to the design of the POD screen, we discuss: image formation, image projection, and optical design constraints.

  9. Natural xenobiotics to prevent cyanobacterial and algal growth in freshwater: contrasting efficacy of tannic acid, gallic acid, and gramine.

    PubMed

    Laue, Pauline; Bährs, Hanno; Chakrabarti, Shumon; Steinberg, Christian E W

    2014-06-01

    Allelochemical action against planktonic phototrophs is one central issue in freshwater ecology and quality management. To determine some basic mechanisms of this toxic action, we exposed the coccal green alga, Desmodesmus armatus, and the coccal cyanobacterium, Microcystis aeruginosa, in a batch culture well-supplied with carbon dioxide to increasing concentrations of the polyphenols tannic acid and gallic acid and the alkaloid gramine. The phototrophs were checked after 2d and at the end of the culture for biomass-based growth rates, cell volume, maximum quantum yield of photosystem II (ΦPSIImax), chlorophyll a content (chla) after 2d and at the end of the culture, and lipid peroxidation only at the end of the culture. During the culture, the pH rose from 7.64 to 10.95, a pH characteristic of eutrophic freshwater bodies during nuisance algal blooms. All xenobiotics reduced the growth rate, ΦPSIImax, and chla during the first 2d with M. aeruginosa being more sensitive to the polyphenols than D. armatus. The efficacy of the polyphenols declined with increasing pH, indicating potential polymerization and corresponding reduced bioavailability of the polyphenols. In contrast to the polyphenols, gramine increased its toxic action over time, independent of the prevailing pH. All exposures caused slight to severe lipid peroxidation (LPO) in the phototrophs. Hence, one mechanism of growth inhibition may be oxidative stress-mediated reduction in photosynthesis. The presented results suggest that in successful field trials with leachate, the prevailing environmental conditions may inactivate polyphenols and xenobiotics other than polyphenols may be more effective.

  10. Cyclophosphamide-induced Hepatotoxicity in Wistar Rats: The Modulatory Role of Gallic Acid as a Hepatoprotective and Chemopreventive Phytochemical

    PubMed Central

    Oyagbemi, Ademola Adetokunbo; Omobowale, Olutayo Temidayo; Asenuga, Ebunoluwa Rachael; Akinleye, Akinrinde Stephen; Ogunsanwo, Rachael Omolola; Saba, Adebowale Bernard

    2016-01-01

    Background: Gallic acid (GA) is an endogenous plant phenol known to have antioxidant, free radical scavenging ability, anti-inflammatory, anti-cancer, and anti-fungal properties. The aim of this study was to assess the protective effect of GA on cyclophosphamide (CPA)-induced hepatotoxicity in male Wistar rats. Methods: Sixty rats were grouped into six groups of 10 rats per group. Group 1 received distilled water. Group 2 received CPA at 200 mg/kg single dose intraperitoneally on day 1. Groups 3 and 4 received a single dose of CPA (200 mg/kg) intraperitoneally on day 1 and then were treated with GA at 60 and 120 mg/kg body weight for 14 days, respectively. Rats in Groups 5 and 6 only received GA at 60 and 120 mg/kg body weight for 14 days, respectively. GA was administered orally. Results: CPA induced hepatic damage as indicated by significant elevation (P < 0.05) in aspartate aminotransferase, organ weight, and evidence by the histological study. CPA also induced hepatic oxidative stress as indicated by significant elevation (P < 0.05) in malondialdehyde content, hydrogen peroxide (H2O2) generation, nitrite level, and the level of glutathione (GSH) peroxidase crashed in the CPA-treated group. GA enhanced the antioxidant defense system as indicated by significant elevation (P < 0.05) in GSH level, catalase activity, and GSH-S-transferase activity. Conclusions: Taken together, the result of this present study shows that GA has a protective effect on CPA-induced hepatotoxicity. PMID:27076889

  11. Tousled kinase activator, gallic acid, promotes homologous recombinational repair and suppresses radiation cytotoxicity in salivary gland cells.

    PubMed

    Timiri Shanmugam, Prakash Srinivasan; Nair, Renjith Parameshwaran; De Benedetti, Arrigo; Caldito, Gloria; Abreo, Fleurette; Sunavala-Dossabhoy, Gulshan

    2016-04-01

    Accidental or medical radiation exposure of the salivary glands can gravely impact oral health. Previous studies have shown the importance of Tousled-like kinase 1 (TLK1) and its alternate start variant TLK1B in cell survival against genotoxic stresses. Through a high-throughput library screening of natural compounds, the phenolic phytochemical, gallic acid (GA), was identified as a modulator of TLK1/1B. This small molecule possesses anti-oxidant and free radical scavenging properties, but in this study, we report that in vitro it promotes survival of human salivary acinar cells, NS-SV-AC, through repair of ionizing radiation damage. Irradiated cells treated with GA show improved clonogenic survival compared to untreated controls. And, analyses of DNA repair kinetics by alkaline single-cell gel electrophoresis and γ-H2AX foci immunofluorescence indicate rapid resolution of DNA breaks in drug-treated cells. Study of DR-GFP transgene repair indicates GA facilitates homologous recombinational repair to establish a functional GFP gene. In contrast, inactivation of TLK1 or its shRNA knockdown suppressed resolution of radiation-induced DNA tails in NS-SV-AC, and homology directed repair in DR-GFP cells. Consistent with our results in culture, animals treated with GA after exposure to fractionated radiation showed better preservation of salivary function compared to saline-treated animals. Our results suggest that GA-mediated transient modulation of TLK1 activity promotes DNA repair and suppresses radiation cytoxicity in salivary gland cells.

  12. Effective color design for displays

    NASA Astrophysics Data System (ADS)

    MacDonald, Lindsay W.

    2002-06-01

    Visual communication is a key aspect of human-computer interaction, which contributes to the satisfaction of user and application needs. For effective design of presentations on computer displays, color should be used in conjunction with the other visual variables. The general needs of graphic user interfaces are discussed, followed by five specific tasks with differing criteria for display color specification - advertising, text, information, visualization and imaging.

  13. Alternative display and interaction devices

    NASA Technical Reports Server (NTRS)

    Bolas, M. T.; McDowall, I. E.; Mead, R. X.; Lorimer, E. R.; Hackbush, J. E.; Greuel, C.

    1995-01-01

    While virtual environment systems are typically thought to consist of a head mounted display and a flex-sensing glove, alternative peripheral devices are beginning to be developed in response to application requirements. Three such alternatives are discussed: fingertip sensing gloves, fixed stereoscopic viewers, and counterbalanced head mounted displays. A subset of commercial examples that highlight each alternative is presented as well as a brief discussion of interesting engineering and implementation issues.

  14. Withanolides and Sucrose Esters from Physalis neomexicana.

    PubMed

    Cao, Cong-Mei; Wu, Xiaoqing; Kindscher, Kelly; Xu, Liang; Timmermann, Barbara N

    2015-10-23

    Four withanolides (1-4) and two sucrose esters (5, 6) were isolated from the aerial parts of Physalis neomexicana. The structures of 1-6 were elucidated through a variety of spectroscopic techniques. Cytotoxicity studies of the isolates revealed that 2 inhibited human breast cancer cell lines (MDA-MB-231 and MCF-7) with IC50 values of 1.7 and 6.3 μM, respectively.

  15. Caffeic Acid Phenethyl Ester and Therapeutic Potentials

    PubMed Central

    Karim, Sabiha; Akram, Muhammad Rouf; Khan, Shujaat Ali; Azhar, Saira; Mumtaz, Amara; Bin Asad, Muhammad Hassham Hassan

    2014-01-01

    Caffeic acid phenethyl ester (CAPE) is a bioactive compound of propolis extract. The literature search elaborates that CAPE possesses antimicrobial, antioxidant, anti-inflammatory, and cytotoxic properties. The principal objective of this review article is to sum up and critically assess the existing data about therapeutic effects of CAPE in different disorders. The findings elaborate that CAPE is a versatile therapeutically active polyphenol and an effective adjuvant of chemotherapy for enhancing therapeutic efficacy and diminishing chemotherapy-induced toxicities. PMID:24971312

  16. One new triterpene ester from Nepeta suavis.

    PubMed

    Hussain, Javid; Khan, Farman Ullah; Ur Rehman, Najeeb; Ullah, Riaz; Mohmmad, Zia; Tasleem, S; Naeem, A; Shah, M Raza

    2009-12-01

    One new tetracyclic triterpene ester (1) has been isolated from the chloroform-soluble portion of the whole plant of Nepeta suavis along with two known compounds, namely artemetin (2) and jaceidin (3). The structures of the isolated compounds were assigned on the basis of their (1)H and (13)C NMR spectra including two-dimensional NMR techniques such as COSY, HMQC, and HMBC experiments and comparison with the literature data.

  17. Future of autostereoscopic electronic displays

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny

    1992-06-01

    Recently there has been significant activity in the attempt to develop autostereoscopic electronic displays. An interesting variation of the panoramagram, the moving slit technique, was described by Collender in the early seventies, and there have been various new types of volumetric display techniques, such as the Spacegraph acoustical mirror and the Texas Instruments laser scanned revolving surface. Lately liquid crystal technology has been employed by NTT and Dimension Technologies, offering the promise of a true three- dimensional display without the need for individual viewing devices. There are fundamental considerations with regard to presentation of visual information that provide constraints with regard to making such products competitive compared with current field-sequential electronic displays. These field-sequential displays have been successful in the marketplace and provide a standard against which the performance of new products must be measured. Products like CrystalEyesR allow any number of spectators to view the image, and have a high degree of compatibility with the present computer graphics and video infrastructures -- an important issue for manufacturers integrating such products into, for example, workstations, and for the user in terms of price and ease of use.

  18. Mask lithography for display manufacturing

    NASA Astrophysics Data System (ADS)

    Sandstrom, T.; Ekberg, P.

    2010-05-01

    The last ten years have seen flat displays conquer our briefcases, desktops, and living rooms. There has been an enormous development in production technology, not least in lithography and photomasks. Current masks for large displays are more than 2 m2 and make 4-6 1X prints on glass substrates that are 9 m2. One of the most challenging aspects of photomasks for displays is the so called mura, stripes or blemishes which cause visible defects in the finished display. For the future new and even tighter maskwriter specifications are driven by faster transistors and more complex pixel layouts made necessary by the market's wish for still better image quality, multi-touch panels, 3D TVs, and the next wave of e-book readers. Large OLED screens will pose new challenges. Many new types of displays will be lowcost and use simple lithography, but anything which can show video and high quality photographic images needs a transistor backplane and sophisticated masks for its production.

  19. Three-dimensional display technologies

    PubMed Central

    Geng, Jason

    2014-01-01

    The physical world around us is three-dimensional (3D), yet traditional display devices can show only two-dimensional (2D) flat images that lack depth (i.e., the third dimension) information. This fundamental restriction greatly limits our ability to perceive and to understand the complexity of real-world objects. Nearly 50% of the capability of the human brain is devoted to processing visual information [Human Anatomy & Physiology (Pearson, 2012)]. Flat images and 2D displays do not harness the brain’s power effectively. With rapid advances in the electronics, optics, laser, and photonics fields, true 3D display technologies are making their way into the marketplace. 3D movies, 3D TV, 3D mobile devices, and 3D games have increasingly demanded true 3D display with no eyeglasses (autostereoscopic). Therefore, it would be very beneficial to readers of this journal to have a systematic review of state-of-the-art 3D display technologies. PMID:25530827

  20. Phosphors for flat panel emissive displays

    SciTech Connect

    Anderson, M.T.; Walko, R.J.; Phillips, M.L.F.

    1995-07-01

    An overview of emissive display technologies is presented. Display types briefly described include: cathode ray tubes (CRTs), field emission displays (FEDs), electroluminescent displays (ELDs), and plasma display panels (PDPs). The critical role of phosphors in further development of the latter three flat panel emissive display technologies is outlined. The need for stable, efficient red, green, and blue phosphors for RGB fall color displays is emphasized.