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Sample records for acid sa methyl

  1. Functional analysis of a tomato salicylic acid methyl transferase and its role in synthesis of the flavor volatile methyl salicylate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methyl salicylate (MeSA) is a volatile plant secondary metabolite that is an important contributor to taste and scent of many fruits and flowers. It is synthesized from salicylic acid (SA), a phytohormone that contributes to plant pathogen defense. MeSA is synthesized by members of a family of O-met...

  2. Isopropyl methyl phosphonic acid (IMPA)

    Integrated Risk Information System (IRIS)

    Isopropyl methyl phosphonic acid ( IMPA ) ; CASRN 1832 - 54 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assess

  3. A novel methyltransferase from the intracellular pathogen Plasmodiophora brassicae methylates salicylic acid.

    PubMed

    Ludwig-Müller, Jutta; Jülke, Sabine; Geiß, Kathleen; Richter, Franziska; Mithöfer, Axel; Šola, Ivana; Rusak, Gordana; Keenan, Sandi; Bulman, Simon

    2015-05-01

    The obligate biotrophic pathogen Plasmodiophora brassicae causes clubroot disease in Arabidopsis thaliana, which is characterized by large root galls. Salicylic acid (SA) production is a defence response in plants, and its methyl ester is involved in systemic signalling. Plasmodiophora brassicae seems to suppress plant defence reactions, but information on how this is achieved is scarce. Here, we profile the changes in SA metabolism during Arabidopsis clubroot disease. The accumulation of SA and the emission of methylated SA (methyl salicylate, MeSA) were observed in P. brassicae-infected Arabidopsis 28 days after inoculation. There is evidence that MeSA is transported from infected roots to the upper plant. Analysis of the mutant Atbsmt1, deficient in the methylation of SA, indicated that the Arabidopsis SA methyltransferase was not responsible for alterations in clubroot symptoms. We found that P. brassicae possesses a methyltransferase (PbBSMT) with homology to plant methyltransferases. The PbBSMT gene is maximally transcribed when SA production is highest. By heterologous expression and enzymatic analyses, we showed that PbBSMT can methylate SA, benzoic and anthranilic acids.

  4. Effect of methyl salicylate (MeSA), an elicitor on growth, physiology and pathology of resistant and susceptible rice varieties

    PubMed Central

    Kalaivani, Kandaswamy; Kalaiselvi, Marimuthu Maruthi; Senthil-Nathan, Sengottayan

    2016-01-01

    Methyl salicylate (MeSA) is a volatile organic compound synthesized from salicylic acid (SA) a plant hormone that helps to fight against plant disease. Seed treatment with MeSA, is an encouraging method to the seed industry to produce more growth and yield. The aim of our study is to find out the growth, development and disease tolerance of rice seed treated with different concentrations of MeSA. Also the seed treatments were studied to determine whether they directly influenced seedling emergence and growth in rice (Oryza sativa L) cultivars ‘IR 20, IR 50, IR 64, ASD 16, ASD 19 and ADT 46’ under greenhouse condition. MeSA seed treatments at 25, 50, 75 and 100 mg/L significantly increased seedling emergence. Effects were stronger in IR 50, and IR 64 and the effects were dose dependent, although the relationship between dose and effect was not always linear. MeSA seed treated rice plant against bacterial blight were analyzed. Bacterial blight was more effectively controlled by the seed treated with 100 mg/L than others. These results suggest that seed treatment with MeSA alters plant physiology in ways that may be useful for crop production as well as protection. PMID:27725719

  5. Salicylic acid (SA) bioaccessibility from SA-based poly(anhydride-ester).

    PubMed

    Rogers, Michael A; Yan, Yim-Fan; Ben-Elazar, Karen; Lan, Yaqi; Faig, Jonathan; Smith, Kervin; Uhrich, Kathryn E

    2014-09-08

    The bioaccessibility of salicylic acid (SA) can be effectively modified by incorporating the pharmacological compound directly into polymers such as poly(anhydride-esters). After simulated digestion conditions, the bioaccessibility of SA was observed to be statistically different (p < 0.0001) in each sample: 55.5 ± 2.0% for free SA, 31.2 ± 2.4% the SA-diglycolic acid polymer precursor (SADG), and 21.2 ± 3.1% for SADG-P (polymer). The release rates followed a zero-order release rate that was dependent on several factors, including (1) solubilization rate, (2) macroscopic erosion of the powdered polymer, (3) hydrolytic cleavage of the anhydride bonds, and (4) subsequent hydrolysis of the polymer precursor (SADG) to SA and diglycolic acid.

  6. Effect of methyl jasmonate, salicylic acid, Headline and Stadium on sucrose yield and storage properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methyl jasmonate (MeJA) and salicylic acid (SA) have been reported to enhance yield and protect crop plants and products against abiotic stresses and diseases. The effect of these compounds on sugarbeets, however, is unknown. Research was conducted in 2015 and 2016 to investigate the effects of an e...

  7. 2-Methyl-4-chlorophenoxyacetic acid (MCPA)

    Integrated Risk Information System (IRIS)

    2 - Methyl - 4 - chlorophenoxyacetic acid ( MCPA ) ; CASRN 94 - 74 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard

  8. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  9. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  10. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  11. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  12. 40 CFR 721.8660 - Propionic acid methyl ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Propionic acid methyl ester (generic... Substances § 721.8660 Propionic acid methyl ester (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a propionic acid methyl...

  13. Neural Tube Defects, Folic Acid and Methylation

    PubMed Central

    Imbard, Apolline; Benoist, Jean-François; Blom, Henk J.

    2013-01-01

    Neural tube defects (NTDs) are common complex congenital malformations resulting from failure of the neural tube closure during embryogenesis. It is established that folic acid supplementation decreases the prevalence of NTDs, which has led to national public health policies regarding folic acid. To date, animal studies have not provided sufficient information to establish the metabolic and/or genomic mechanism(s) underlying human folic acid responsiveness in NTDs. However, several lines of evidence suggest that not only folates but also choline, B12 and methylation metabolisms are involved in NTDs. Decreased B12 vitamin and increased total choline or homocysteine in maternal blood have been shown to be associated with increased NTDs risk. Several polymorphisms of genes involved in these pathways have also been implicated in risk of development of NTDs. This raises the question whether supplementation with B12 vitamin, betaine or other methylation donors in addition to folic acid periconceptional supplementation will further reduce NTD risk. The objective of this article is to review the role of methylation metabolism in the onset of neural tube defects. PMID:24048206

  14. Neural tube defects, folic acid and methylation.

    PubMed

    Imbard, Apolline; Benoist, Jean-François; Blom, Henk J

    2013-09-17

    Neural tube defects (NTDs) are common complex congenital malformations resulting from failure of the neural tube closure during embryogenesis. It is established that folic acid supplementation decreases the prevalence of NTDs, which has led to national public health policies regarding folic acid. To date, animal studies have not provided sufficient information to establish the metabolic and/or genomic mechanism(s) underlying human folic acid responsiveness in NTDs. However, several lines of evidence suggest that not only folates but also choline, B12 and methylation metabolisms are involved in NTDs. Decreased B12 vitamin and increased total choline or homocysteine in maternal blood have been shown to be associated with increased NTDs risk. Several polymorphisms of genes involved in these pathways have also been implicated in risk of development of NTDs. This raises the question whether supplementation with B12 vitamin, betaine or other methylation donors in addition to folic acid periconceptional supplementation will further reduce NTD risk. The objective of this article is to review the role of methylation metabolism in the onset of neural tube defects.

  15. The plastidial retrograde signal methyl erythritol cyclopyrophosphate is a regulator of salicylic acid and jasmonic acid crosstalk.

    PubMed

    Lemos, Mark; Xiao, Yanmei; Bjornson, Marta; Wang, Jin-Zheng; Hicks, Derrick; Souza, Amancio de; Wang, Chang-Quan; Yang, Panyu; Ma, Shisong; Dinesh-Kumar, Savithramma; Dehesh, Katayoon

    2016-03-01

    The exquisite harmony between hormones and their corresponding signaling pathways is central to prioritizing plant responses to simultaneous and/or successive environmental trepidations. The crosstalk between jasmonic acid (JA) and salicylic acid (SA) is an established effective mechanism that optimizes and tailors plant adaptive responses. However, the underlying regulatory modules of this crosstalk are largely unknown. Global transcriptomic analyses of mutant plants (ceh1) with elevated levels of the stress-induced plastidial retrograde signaling metabolite 2-C-methyl-D-erythritol cyclopyrophosphate (MEcPP) revealed robustly induced JA marker genes, expected to be suppressed by the presence of constitutively high SA levels in the mutant background. Analyses of a range of genotypes with varying SA and MEcPP levels established the selective role of MEcPP-mediated signal(s) in induction of JA-responsive genes in the presence of elevated SA. Metabolic profiling revealed the presence of high levels of the JA precursor 12-oxo-phytodienoic acid (OPDA), but near wild type levels of JA in the ceh1 mutant plants. Analyses of coronatine-insensitive 1 (coi1)/ceh1 double mutant plants confirmed that the MEcPP-mediated induction is JA receptor COI1 dependent, potentially through elevated OPDA. These findings identify MEcPP as a previously unrecognized central regulatory module that induces JA-responsive genes in the presence of high SA, thereby staging a multifaceted plant response within the environmental context.

  16. Production of methyl-vinyl ketone from levulinic acid

    DOEpatents

    Dumesic, James A.; West; Ryan M.

    2011-06-14

    A method for converting levulinic acid to methyl vinyl ketone is described. The method includes the steps of reacting an aqueous solution of levulinic acid, over an acid catalyst, at a temperature of from room temperature to about 1100 K. Methyl vinyl ketone is thereby formed.

  17. Pyrrolidone - a new solvent for the methylation of humic acid

    USGS Publications Warehouse

    Wershaw, R. L.; Pinckney, D.J.; Booker, S.E.

    1975-01-01

    In the past, humic acid has been methylated by suspending it in a solution of diazomethane in diethyl ether, and degrading the partly methylated humic acid to release those parts of the molecule that were methylated. Only small fragments of the molecule have been identified by this technique. In the procedure described here the humic acid is dissolved in 2-pyrrolidone and methylated by the addition of diazomethane in diethyl ether and ethanol to the solution. Because the humic acid is completely dissolved in the reaction medium, disaggregation of the humic acid particles takes place and much more complete methylation is obtained. The methylated products may be fractionated by countercurrent distribution and analyzed by mass spectrometry.

  18. Lipoxygenase in Caragana jubata responds to low temperature, abscisic acid, methyl jasmonate and salicylic acid.

    PubMed

    Bhardwaj, Pardeep Kumar; Kaur, Jagdeep; Sobti, Ranbir Chander; Ahuja, Paramvir Singh; Kumar, Sanjay

    2011-09-01

    Lipoxygenase (LOX) catalyses oxygenation of free polyunsaturated fatty acids into oxylipins, and is a critical enzyme of the jasmonate signaling pathway. LOX has been shown to be associated with biotic and abiotic stress responses in diverse plant species, though limited data is available with respect to low temperature and the associated cues. Using rapid amplification of cDNA ends, a full-length cDNA (CjLOX) encoding lipoxygenase was cloned from apical buds of Caragana jubata, a temperate plant species that grows under extreme cold. The cDNA obtained was 2952bp long consisting of an open reading frame of 2610bp encoding 869 amino acids protein. Multiple alignment of the deduced amino acid sequence with those of other plants demonstrated putative LH2/ PLAT domain, lipoxygenase iron binding catalytic domain and lipoxygenase_2 signature sequences. CjLOX exhibited up- and down-regulation of gene expression pattern in response to low temperature (LT), abscisic acid (ABA), methyl jasmonate (MJ) and salicylic acid (SA). Among all the treatments, a strong up-regulation was observed in response to MJ. Data suggests an important role of jasmonate signaling pathway in response to LT in C. jubata.

  19. Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA).

    PubMed

    Gao, Zhengquan; Li, Yan; Wu, Guanxun; Li, Guoqiang; Sun, Haifeng; Deng, Suzhen; Shen, Yicheng; Chen, Guoqiang; Zhang, Ruihao; Meng, Chunxiao; Zhang, Xiaowen

    2015-01-01

    Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis.

  20. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2... 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2'-(1,2-diazenediyl)bis - and...

  1. 6-methyl-8-hexadecenoic acid: A novel fatty acid from the marine spongeDesmapsama anchorata.

    PubMed

    Carballeira, N M; Maldonado, M E

    1988-07-01

    The novel fatty acid 7-methyl-8-hexadecenoic (1) was identified in the marine spongeDesmapsama anchorata. Other interesting fatty acids identified were 14-methyl-8-hexadecenoic (2), better known through its methyl ester as one of the components of the sex attractant of the female dermestid beetle, and the saturated fatty acid 3-methylheptadecanoic (3), known to possess larvicidal activity. The main phospholipid fatty acids encountered inD. anchorata were palmitic (16∶0), behenic (22∶0) and 5,9-hexacosadienoic acid (26∶2), which together accounted for 50% of the total phospholipid fatty acid mixture.

  2. Salicylic acid and methyl jasmonate improve chilling tolerance in cold-stored lemon fruit (Citrus limon).

    PubMed

    Siboza, Xolani Irvin; Bertling, Isa; Odindo, Alfred Oduor

    2014-11-15

    Chilling injury (CI) is associated with the degradation of membrane integrity which can be aligned to phenolic oxidation activated by polyphenol oxidase (PPO) and peroxidase (POD), enzymes responsible for tissue browning. Phenylalanine ammonia-lyase (PAL) is a further enzyme prominent in the phenolic metabolism that is involved in acclimation against chilling stress. It was hypothesized that treatment with methyl jasmonate (MJ) and salicylic acid (SA) may enhance chilling tolerance in lemon fruit by increasing the synthesis of total phenolics and PAL by activating the key enzyme regulating the shikimic acid pathway whilst inhibiting the activity of POD and PPO. Lemon fruit were treated with 10μM MJ, 2mM SA or 10μM MJ plus 2mM SA, waxed, stored at -0.5, 2 or 4.5°C for up to 28 days plus 7 days at 23°C. Membrane integrity was studied by investigating membrane permeability and the degree of membrane lipid peroxidation in lemon flavedo following cold storage. The 10μM MJ plus 2mM SA treatment was most effective in enhancing chilling tolerance of lemon fruit, significantly reducing chilling-induced membrane permeability and membrane lipid peroxidation of lemon flavedo tissue. This treatment also increased total phenolics and PAL activity in such tissue while inhibiting POD activity, the latter possibly contributing to the delay of CI manifestation. PPO activity was found to be a poor biochemical marker of CI. Treatment with 10μM MJ plus 2mM SA resulted in an alteration of the phenolic metabolism, enhancing chilling tolerance, possibly through increased production of total phenolics and the activation of PAL and inhibition of POD.

  3. Succinyl derivatives of N-tris (hydroxymethyl) methyl-2-aminoethane sulphonic acid: their effects on the frog neuromuscular junction.

    PubMed Central

    del Castillo, J.; Escalona de Motta, G.; Eterović, V. A.; Ferchmin, P. A.

    1985-01-01

    Succinic anhydride (SA) dissolved in Ringer solution buffered with N-tris (hydroxymethyl) methyl-2-aminoethane sulphonic acid (SA-TES solution) potentiates the depolarizing action of acetylcholine (ACh, 10-40 microM) on frog muscle and the tension induced by bath application of this agonist. Applied from one side of a double-barrelled micropipette, SA-TES increases the amplitude of iontophoretically elicited ACh potentials. The potentiation of the effects of ACh by SA-TES does not involve changes in either the activity of the ACh esterase or the input resistance of the muscle membrane. For depolarizations of frog sartorius muscle, dose-response relationships obtained for ACh concentrations from 0.5 to 20 microM indicate that SA-TES increases the apparent affinity of ACh by a factor of 3. SA-TES exerts an "accelerating' effect on the responses elicited by bath-applied ACh; i.e., it increases the rate of depolarization when ACh is added to the bath and the rate of repolarization upon washing out. These effects are particularly marked in preparations treated with neostigmine (3 microM). SA-TES does not potentiate the depolarizing action of agonists which do not contain an ester group. Moreover, the time course of the responses elicited by these compounds is not influenced by SA-TES. SA-TES fails to influence significantly the effects of the neurally released transmitter. Only a 10% increase in the average amplitude of the endplate potentials was observed. SA hydrolyzes in about 30 min at room temperature; however the SA-TES solution retains its activity for several weeks. Succinate is inactive, and so is SA in Ringer buffered with phosphate. The SA-TES solution contains seven succinyl-TES derivatives, which were separated by ion-exchange chromatography and paper chromatography. At concentrations between 1 to 150 microM, these succinyl-TES derivatives affected the ACh-induced contraction of frog rectus abdominus muscle. The most abundant derivative potentiated the

  4. Effects of the new ethacrynic acid derivative SA9000 on intraocular pressure in cats and monkeys.

    PubMed

    Shimazaki, Atsushi; Ichikawa, Masaki; Rao, Ponugoti Vasantha; Kirihara, Tomoko; Konomi, Kouji; Epstein, David Lee; Hara, Hideaki

    2004-07-01

    To evaluate the pharmacological characteristics of the new ethacrynic acid (ECA) derivative SA9000, we examined its ocular hypotensive effects in cats and cynomolgus monkeys, its corneal toxicity in rabbits, and its binding affinities for forty-three receptors, ion channels, and second messenger systems. A 20 microl injection into the anterior chamber of eye (intracameral injection) of 0.1 mM SA9000 significantly reduced intraocular pressure (IOP) 3.8 mmHg in cats. A 10 microl intracameral injection of 1 mM SA9000 significantly reduced IOP 7 mmHg in living monkeys without evidence of in vivo (or in vitro) toxicity. The ocular hypotensive effect of SA9000 in monkeys was greater than that of ECA. The morphology of corneal endothelial and epithelial cells in rabbit eyes after intracameral injection of SA9000 was observed using electron microphotography. SA9000 at 2 mM did not induce any abnormalities, indicating that it has no corneal toxicity at a concentration higher than the minimum needed for an ocular hypotensive effect (1 mM). SA9000 at 0.01 mM showed negligible binding affinity for, or inhibition of, forty-three different receptors, ion channel proteins, and second messenger systems. These findings indicate that SA9000 has the potential to be both effective and safe as an ocular hypotensive drug, although the mechanism of action remains unclear.

  5. Microwave-assisted pyrolysis of methyl ricinoleate for continuous production of undecylenic acid methyl ester (UAME).

    PubMed

    Nie, Yong; Duan, Ying; Gong, Ruchao; Yu, Shangzhi; Lu, Meizhen; Yu, Fengwen; Ji, Jianbing

    2015-06-01

    Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C.

  6. Effects of high-melting methyl esters on crystallization properties of fatty acid methyl ester mixtures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel is a renewable alternative diesel fuel made from vegetable oils and animal fats. The most common form of biodiesel in the United States are fatty acid methyl esters (FAME) from soybean, canola, and used cooking oils, waste greases, and tallow. Cold flow properties of biodiesel depend on th...

  7. Phospholipidic signaling and vanillin production in response to salicylic acid and methyl jasmonate in Capsicum chinense J. cells.

    PubMed

    Altúzar-Molina, Alma R; Muñoz-Sánchez, J Armando; Vázquez-Flota, Felipe; Monforte-González, Miriam; Racagni-Di Palma, Graciela; Hernández-Sotomayor, S M Teresa

    2011-02-01

    The phospholipidic signal transduction system involves generation of second messengers by hydrolysis or changes in phosphorylation state. Several studies have shown that the signaling pathway forms part of plant response to phytoregulators such as salicylic acid (SA) and methyl jasmonate (MJ), which have been widely used to stimulate secondary metabolite production in cell cultures. An evaluation was made of the effect of SA and MJ on phospholipidic signaling and capsaicinoid production in Capsicum chinense Jacq. suspension cells. Treatment with SA inhibited phospholipase C (PLC) (EC: 3.1.4.3) and phospholipase D (PLD) (EC: 3.1.4.4) activities in vitro, but increased lipid kinase activities in vitro at different SA concentrations. Treatment with MJ produced increases in PLC and PLD activities, while lipid kinase activities were variable and dose-dependent. The production of vanillin, a precursor of capsaicinoids, increased at specific SA or MJ doses. Preincubation with neomycin, a phospholipase inhibitor, before SA or MJ treatment inhibits increase in vanillin production which suggests that phospholipidic second messengers may participate in the observed increase in vanillin production.

  8. 76 FR 41135 - 2-Propenoic acid, 2-methyl-, phenylmethyl ester, polymer with 2-propenoic acid and sodium 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... and sodium 2-methyl-2- -1- propanesulfonate (1:1), peroxydisulfuric acid ( 202) sodium salt (1:2...-Propenoic acid, 2-methyl-, phenylmethyl ester, polymer with 2-propenoic acid and sodium 2-methyl- 2- -1-propanesulfonate (1:1), peroxydisulfuric acid ( 202) sodium salt (1:2)-initiated (also known here as: ``the...

  9. 40 CFR 721.1576 - 1,3-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... cyclohexyl] methyl] ester. 721.1576 Section 721.1576 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,3-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1162; CAS...

  10. 40 CFR 721.1578 - 1,4-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cyclohexyl] methyl] ester. 721.1578 Section 721.1578 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,4-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1164; CAS...

  11. 40 CFR 721.1576 - 1,3-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cyclohexyl] methyl] ester. 721.1576 Section 721.1576 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,3-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1162; CAS...

  12. 40 CFR 721.1578 - 1,4-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... cyclohexyl] methyl] ester. 721.1578 Section 721.1578 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,4-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1164; CAS...

  13. 40 CFR 721.1576 - 1,3-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... cyclohexyl] methyl] ester. 721.1576 Section 721.1576 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,3-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1162; CAS...

  14. 40 CFR 721.1578 - 1,4-Benzenedicarboxylic acid, bis[[4-[(ethenyloxy)methyl] cyclohexyl] methyl] ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... cyclohexyl] methyl] ester. 721.1578 Section 721.1578 Protection of Environment ENVIRONMENTAL PROTECTION...] methyl] ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 1,4-benzenedicarboxylic acid, bis cyclohexyl] methyl] ester (PMN P-98-1164; CAS...

  15. Inhibition of N-methyl-N-nitrosourea-induced mutagenicity and DNA methylation by ellagic acid.

    PubMed Central

    Dixit, R; Gold, B

    1986-01-01

    Ellagic acid, a naturally occurring plant phenol, inhibits the activity of the direct-acting mutagen N-methyl-N-nitrosourea (MeNU) in Salmonella typhimurium TA100. Ellagic acid at 0.10, 0.25, 0.50, and 1.00 mM inhibited the mutagenicity of MeNU (0.40 mM) by 3%, 13%, 45%, and 60%, respectively. Ellagic acid (3 mM) also inhibited the mutagenic activity of N,N-dimethylnitrosamine (25-200 mM) in the presence of pyrazole-induced rat liver fraction S-9. The effect of ellagic acid on DNA methylation was studied by incubating 0, 0.72, 1.32, 2.64, and 6.60 mM ellagic acid with DNA (0.9 mM nucleotide) and [3H]MeNU (0.66 mM). HPLC analysis of DNA hydrolysates showed that ellagic acid caused a dose-dependent 36-84% decrease in O6-methylguanine but only a 20% decrease in the 7-methylguanine adduct. Under conditions where methylation at the O6 position of guanine in double-stranded DNA was inhibited 65% by ellagic acid, no significant inhibition of either O6- or 7-methylguanine formation was detected in single-stranded DNA. Affinity-binding studies revealed that [3H]ellagic acid binds equally to double-stranded or single-stranded DNA but that poly(dA X dT) binds 1.5 times as much ellagic acid as does poly(dG X dC). The binding of ellagic acid to DNA is dependent on the concentration of both ellagic acid and DNA. The specific inhibition of O6-methylguanine formation only in double-stranded DNA and the relatively low inhibition of 7-methylguanine formation rule out the possibility that ellagic acid prevents DNA alkylation by scavenging the electrophilic intermediate generated in the hydrolysis of MeNU. The results suggest that ellagic acid inhibition of MeNU-induced mutagenicity is due to specific inhibition of methylation at the O6 position of guanine through an ellagic acid-duplex DNA affinity-binding mechanism. PMID:3464940

  16. 4-(2-Methyl-4-chlorophenoxy) butyric acid (MCPB)

    Integrated Risk Information System (IRIS)

    4 - ( 2 - Methyl - 4 - chlorophenoxy ) butyric acid ( MCPB ) ; CASRN 94 - 81 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Hea

  17. 2-(2-Methyl-4-chlorophenoxy)propionic acid (MCPP)

    Integrated Risk Information System (IRIS)

    2 - ( 2 - Methyl - 4 - chlorophenoxy ) propionic acid ( MCPP ) ; CASRN 93 - 65 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( H

  18. Cinnamyl alcohols and methyl esters of fatty acids from Wedelia prostrata callus cultures.

    PubMed

    El-Mawla, Ahmed M A Abd; Farag, Salwa F; Beuerle, Till

    2011-01-01

    Two methyl esters of fatty acids, namely octadecanoic acid methyl ester (methyl stearate) and hexadecanoic acid methyl ester (methyl palmitate), in addition to four cinnamyl alcohol derivatives, sinapyl alcohol, coniferyl alcohol, p-coumaryl alcohol and coniferyl alcohol 4-O-glucoside (coniferin), were isolated from callus cultures of Wedelia prostrata. The structure of coniferin was established by spectroscopic and chemical methods, while the other compounds were identified by gas chromatography-mass spectrometry and thin layer chromatography in comparison with standards.

  19. Hydroxycinnamoylmalic acids and their methyl esters from pear (Pyrus pyrifolia Nakai) fruit peel.

    PubMed

    Lee, Ki Hoon; Cho, Jeong-Yong; Lee, Hyoung Jae; Ma, Young-Kyu; Kwon, Joseph; Park, Seong Hwa; Lee, Sang-Hyun; Cho, Jeong An; Kim, Wol-Soo; Park, Keun-Hyung; Moon, Jae-Hak

    2011-09-28

    Two novel caffeoylmalic acid methyl esters, 2-O-(trans-caffeoyl)malic acid 1-methyl ester (6) and 2-O-(trans-caffeoyl)malic acid 4-methyl ester (7), were isolated from pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peels. In addition, 5 known hydroxycinnamoylmalic acids and their methyl esters were identified: 2-O-(trans-coumaroyl)malic acid (1), 2-O-(cis-coumaroyl)malic acid (2), 2-O-(cis-coumaroyl)malic acid 1-methyl ester (3), 2-O-(trans-coumaroyl)malic acid 1-methyl ester (4), and 2-O-(trans-caffeoyl)malic acid (phaselic acid, 5). The chemical structures of these compounds were determined by spectroscopic data from ESI MS and NMR. Of all the isolated compounds, five hydroxycinnamoylmalic acids and their methyl esters (2-4, 6, 7) were identified in the pear for the first time.

  20. 40 CFR 721.10448 - Acetic acid, hydroxy- methoxy-, methyl ester, reaction products with substituted alkylamine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester, reaction products with substituted alkylamine (generic). 721.10448 Section 721.10448 Protection... Acetic acid, hydroxy- methoxy-, methyl ester, reaction products with substituted alkylamine (generic). (a... generically as acetic acid, hydroxymethoxy-, methyl ester, reaction products with substituted alkylamine...

  1. 76 FR 69659 - Methacrylic Acid-Methyl Methacrylate-Polyethylene Glycol Monomethyl Ether Methacrylate Graft...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... AGENCY 40 CFR Part 180 Methacrylic Acid-Methyl Methacrylate-Polyethylene Glycol Monomethyl Ether... residues of methacrylic acid-methyl methacrylate- polyethylene glycol monomethyl ether methacrylate graft... permissible level for residues of methacrylic acid-methyl methacrylate-polyethylene glycol monomethyl...

  2. Biodegradation kinetics of trans-4-methyl-1-cyclohexane carboxylic acid.

    PubMed

    Paslawski, Janice C; Headley, John V; Hill, Gordon A; Nemati, Mehdi

    2009-02-01

    Naphthenic acids are a complex mixture of organic compounds which naturally occur in crude oil. Low molecular weight components of the naphthenic acids are known to be toxic in aquatic environments and there is a need to better understand the factors controlling the kinetics of their biodegradation. In this study, a relatively low molecular weight naphthenic acid compound (trans-isomer of 4-methyl-1-cyclohexane carboxylic acid) and a microbial culture developed in our laboratory were used to study the biodegradation of this naphthenic acid and to evaluate the kinetics of the process in batch cultures. The initial concentration of trans-4-methyl-1-cyclohexane carboxylic acid (50-750 mg l(-1)) did not affect the maximum specific growth rate of the bacteria at 23 degrees C (0.52 day(-1)) to the maximum biodegradable concentration (750 mg l(-1)). The maximum yield observed at this temperature and at a neutral pH was 0.21 mg of biomass per milligram of substrate. Batch experiments indicated that biodegradation can be achieved at low temperatures; however, the biodegradation rate at room temperature (23 degrees C) and neutral pH was 5 times faster than that observed at 4 degrees C. Biodegradation at various pH conditions indicated a maximum specific growth rate of 1.69 day(-1) and yield (0.41 mg mg(-1)) at a pH of 10.

  3. Effects of the new ethacrynic acid oxime derivative SA12590 on intraocular pressure in cats and monkeys.

    PubMed

    Shimazaki, Atsushi; Kirihara, Tomoko; Rao, Ponugoti Vasantha; Tajima, Hisashi; Matsugi, Takeshi; Epstein, David Lee

    2007-08-01

    To evaluate the pharmacological characteristics of SA12590, a new oxime-derivative of the ethacrynic acid (ECA) derivative SA9000, we examined both its ocular hypotensive effects (in ocular normotensive cats and cynomolgus monkeys) and its potential corneal toxicity (in rats). A 50 microl topical administration of 3% SA12590 significantly reduced intraocular pressure (IOP) (by 3.5 mmHg) in anesthetized cats (p<0.05). Twenty-four hours after 3 drops (5-min intervals) of 20 microl 3% SA12590, IOP was reduced by 8 mmHg (p<0.05, n=4) in conscious monkeys without evidence of corneal toxicity. Three days' daily single 20 microl dosing with 3% SA12590 reduced IOP by 4 mmHg (p<0.01, n=3) at 72 h after the first administration in conscious monkeys. The toxicity of topically administered 20 microl 3% SA9000 or SA12590 (3 drops with 5-min intervals) on rat corneal epithelium was assessed using a photo-slit lamp. In this study, 3% SA12590, unlike 3% SA9000, exhibited no corneal toxicity. In a glutathione assay for sulfhydryl (SH) reactivity, SA12590, unlike SA9000, displayed no in vitro SH reactivity. Thus, oxime-modification may both improve efficacy towards IOP upon topical administration and improve the safety profile, probably by enhancing corneal penetration and minimizing SH reactivity-related toxicity. These findings indicate that SA12590 has potential as a new ocular hypotensive drug.

  4. Folic acid, methylation and neural tube closure in humans.

    PubMed

    Blom, Henk J

    2009-04-01

    This review provides a brief description of folate use and folic acid metabolism in relation to neural tube defect (NTD) risk. First, a meta-analysis of reduction in NTD recurrence and occurrence risk with periconceptional folic acid supplementation is presented. Second, an overview of the complex folate metabolism is given. Third, SNPs for genes involved in folate and homocysteine metabolism that have been studied in relation to NTD riskare discussed. Fourth, the questions whether folate receptor autoantibodies or hampered methylation are mechanisms underlying NTDs are briefly discussed.

  5. 40 CFR 721.2078 - 1-Piperidinecarboxylic acid, 2-[(dichloro-hydroxy-carbomonocycle)hydrazono]-, methyl ester...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...- -, methyl ester (generic). 721.2078 Section 721.2078 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2078 1-Piperidinecarboxylic acid, 2- -, methyl ester... generically identified as 1-piperidinecarboxylic acid, 2- -, methyl ester (PMN P-96-756) is subject...

  6. 40 CFR 721.2078 - 1-Piperidinecarboxylic acid, 2-[(dichloro-hydroxy-carbomonocycle)hydrazono]-, methyl ester...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...- -, methyl ester (generic). 721.2078 Section 721.2078 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2078 1-Piperidinecarboxylic acid, 2- -, methyl ester... generically identified as 1-piperidinecarboxylic acid, 2- -, methyl ester (PMN P-96-756) is subject...

  7. 40 CFR 721.2078 - 1-Piperidinecarboxylic acid, 2-[(dichloro-hydroxy-carbomonocycle)hydrazono]-, methyl ester...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...- -, methyl ester (generic). 721.2078 Section 721.2078 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2078 1-Piperidinecarboxylic acid, 2- -, methyl ester... generically identified as 1-piperidinecarboxylic acid, 2- -, methyl ester (PMN P-96-756) is subject...

  8. Enhanced glucosinolates in root exudates of Brassica rapa ssp. rapa mediated by salicylic acid and methyl jasmonate.

    PubMed

    Schreiner, Monika; Krumbein, Angelika; Knorr, Dietrich; Smetanska, Iryna

    2011-02-23

    Elicitation studies with salicylic acid (SA) and methyl jasmonate (MJ) inducing a targeted rhizosecretion of high levels of anticarcinogenic glucosinolates in Brassica rapa ssp. rapa plants were conducted. Elicitor applications not only led to an accumulation of individual indole glucosinolates and the aromatic 2-phenylethyl glucosinolate in the turnip organs but also in turnip root exudates. This indicates an extended systemic response, which comprises the phyllosphere with all aboveground plant organs and the rhizosphere including the belowground root system and also root exudates. Both elicitor applications induced a doubling in 2-phenylethyl glucosinolate in root exudates, whereas application of MJ enhanced rhizosecreted indole glucosinolates up to 4-fold. In addition, the time course study revealed that maximal elicitation was observed on the 10th day of SA and MJ treatment. This study may provide an essential contribution using these glucosinolates as bioactive additives in functional foods and nutraceuticals.

  9. Expression of tomato salicylic acid (SA)-responsive pathogenesis-related genes in Mi-1-mediated and SA-induced resistance to root-knot nematodes.

    PubMed

    Molinari, Sergio; Fanelli, Elena; Leonetti, Paola

    2014-04-01

    The expression pattern of pathogenesis-related genes PR-1, PR-2 and PR-5, considered as markers for salicylic acid (SA)-dependent systemic acquired resistance (SAR), was examined in the roots and shoots of tomato plants pre-treated with SA and subsequently infected with root-knot nematodes (RKNs) (Meloidogyne incognita). PR-1 was up-regulated in both roots and shoots of SA-treated plants, whereas the expression of PR-5 was enhanced only in roots. The over-expression of PR-1 in the whole plant occurred as soon as 1 day after SA treatment. Up-regulation of the PR-1 gene was considered to be the main marker of SAR elicitation. One day after treatment, plants were inoculated with active juveniles (J2s) of M. incognita. The number of J2s that entered the roots and started to develop was significantly lower in SA-treated than in untreated plants at 5 and 15 days after inoculation. The expression pattern of PR-1, PR-2 and PR-5 was also examined in the roots and shoots of susceptible and Mi-1-carrying resistant tomato plants infected by RKNs. Nematode infection produced a down-regulation of PR genes in both roots and shoots of SA-treated and untreated plants, and in roots of Mi-carrying resistant plants. Moreover, in resistant infected plants, PR gene expression, in particular PR-1 gene expression, was highly induced in shoots. Thus, nematode infection was demonstrated to elicit SAR in shoots of resistant plants. The data presented in this study show that the repression of host defence SA signalling is associated with the successful development of RKNs, and that SA exogenously added as a soil drench is able to trigger a SAR-like response to RKNs in tomato.

  10. Leaf and root glucosinolate profiles of Chinese cabbage (Brassica rapa ssp. pekinensis) as a systemic response to methyl jasmonate and salicylic acid elicitation.

    PubMed

    Zang, Yun-xiang; Ge, Jia-li; Huang, Ling-hui; Gao, Fei; Lv, Xi-shan; Zheng, Wei-wei; Hong, Seung-beom; Zhu, Zhu-jun

    2015-08-01

    Glucosinolates (GSs) are an important group of defensive phytochemicals mainly found in Brassicaceae. Plant hormones jasmonic acid (JA) and salicylic acid (SA) are major regulators of plant response to pathogen attack. However, there is little information about the interactive effect of both elicitors on inducing GS biosynthesis in Chinese cabbage (Brassica rapa ssp. pekinensis). In this study, we applied different concentrations of methyl jasmonate (MeJA) and/or SA onto the leaf and root of Chinese cabbage to investigate the time-course interactive profiles of GSs. Regardless of the site of the elicitation and the concentrations of the elicitors, the roots accumulated much more GSs and were more sensitive and more rapidly responsive to the elicitors than leaves. Irrespective of the elicitation site, MeJA had a greater inducing and longer lasting effect on GS accumulation than SA. All three components of indole GS (IGS) were detected along with aliphatic and aromatic GSs. However, IGS was a major component of total GSs that accumulated rapidly in both root and leaf tissues in response to MeJA and SA elicitation. Neoglucobrassicin (neoGBC) did not respond to SA but to MeJA in leaf tissue, while it responded to both SA and MeJA in root tissue. Conversion of glucobrassicin (GBC) to neoGBC occurred at a steady rate over 3 d of elicitation. Increased accumulation of 4-methoxy glucobrassicin (4-MGBC) occurred only in the root irrespective of the type of elicitors and the site of elicitation. Thus, accumulation of IGS is a major metabolic hallmark of SA- and MeJA-mediated systemic response systems. SA exerted an antagonistic effect on the MeJA-induced root GSs irrespective of the site of elicitation. However, SA showed synergistic and antagonistic effects on the MeJA-induced leaf GSs when roots and leaves are elicitated for 3 d, respectively.

  11. Complexes of polyadenylic acid and the methyl esters of amino acids

    NASA Technical Reports Server (NTRS)

    Khaled, M. A.; Mulins, D. W., Jr.; Swindle, M.; Lacey, J. C., Jr.

    1983-01-01

    A study of amino acid methyl esters binding to polyadenylic acid supports the theory that the genetic code originated through weak but selective affinities between amino acids and nucleotides. NMR, insoluble complex analysis, and ultraviolet spectroscopy are used to illustrate a correlation between the hydrophybicities of A amino acids and their binding constants, which, beginning with the largest, are in the order of Phe (having nominally a hydrophobic AAA anticodon), Ile, Leu, Val and Gly (having a hydrophilic anticodon with no A). In general, the binding constants are twice the values by Reuben and Polk (1980) for monomeric AMP, which suggests that polymer amino acids are interacting with only one base. No real differences are found betwen poly A binding for free Phe, Phe methyl ester or Phe amide, except that the amide value is slightly lower.

  12. Acid esterification-alkaline transesterification process for methyl ester production from crude rubber seed oil.

    PubMed

    Thaiyasuit, Prachasanti; Pianthong, Kulachate; Worapun, Ittipon

    2012-01-01

    This study aims to examine methods and the most suitable conditions for producing methyl ester from crude rubber seed oil. An acid esterification-alkaline transesterification process is proposed. In the experiment, the 20% FFA of crude rubber seed oil could be reduced to 3% FFA by acid esterification. The product after esterified was then tranesterified by alkaline transesterification process. By this method, the maximum yield of methyl ester was 90% by mass. The overall consumption of methanol was 10.5:1 by molar ratio. The yielded methyl ester was tested for its fuel properties and met required standards. The major fatty acid methyl ester compositions were analyzed and constituted of methyl linoleate 41.57%, methyl oleate 24.87%, and methyl lonolenate 15.16%. Therefore, the cetane number of methyl ester could be estimated as 47.85, while the tested result of motor cetane number was 51.20.

  13. Does Salicylic Acid (SA) Improve Tolerance to Salt Stress in Plants? A Study of SA Effects On Tomato Plant Growth, Water Dynamics, Photosynthesis, and Biochemical Parameters.

    PubMed

    Mimouni, Hajer; Wasti, Salma; Manaa, Arafet; Gharbi, Emna; Chalh, Abdellah; Vandoorne, Bertrand; Lutts, Stanley; Ben Ahmed, Hela

    2016-03-01

    Environmental stresses such as salinity directly impact crop growth, and by extension, world food supply and societal prosperity. It is estimated that over 800 million hectares of land throughout the world are salt-affected. In arid and semi-arid regions, salt concentration can be close to that in the seawater. Hence, there are intensive efforts to improve plant tolerance to salinity and other environmental stressors. Salicylic acid (SA) is an important signal molecule for modulating plant responses to stress. In the present study, we examined, on multiple plant growth related endpoints, whether SA applied through the rooting medium could mitigate the adverse effects of salinity on tomato (Solanum lycopersicum) cv. Marmande. The latter is a hitherto understudied tomato plant from the above perspective; it is a classic variety that produces the large ribbed tomatoes in the Mediterranean and consumed worldwide. We found salt stress negatively affected the growth of cv. Marmande tomato plants. However, the SA-treated plants had greater shoot and root dry mass, leaf area compared to untreated plants when exposed to salt stress. Application of SA restores photosynthetic rates and photosynthetic pigment levels under salt (NaCl) exposure. Leaf water, osmotic potential, stomatal conductance transpiration rate, and biochemical parameters were also ameliorated in SA-treated plants under saline stress conditions. Overall, these data illustrate that SA increases cv. Marmande tomato growth by improving photosynthesis, regulation and balance of osmotic potential, induction of compatible osmolyte metabolism, and alleviating membrane damage. We suggest salicylic acid might be considered as a potential growth regulator to improve tomato plant salinity stress resistance, in the current era of global climate change.

  14. Biosynthesis and metabolism of salicylic acid.

    PubMed Central

    Lee, H I; León, J; Raskin, I

    1995-01-01

    Pathways of salicylic acid (SA) biosynthesis and metabolism in tobacco have been recently identified. SA, an endogenous regulator of disease resistance, is a product of phenylpropanoid metabolism formed via decarboxylation of trans-cinnamic acid to benzoic acid and its subsequent 2-hydroxylation to SA. In tobacco mosaic virus-inoculated tobacco leaves, newly synthesized SA is rapidly metabolized to SA O-beta-D-glucoside and methyl salicylate. Two key enzymes involved in SA biosynthesis and metabolism: benzoic acid 2-hydroxylase, which converts benzoic acid to SA, and UDPglucose:SA glucosyltransferase (EC 2.4.1.35), which catalyzes conversion of SA to SA glucoside have been partially purified and characterized. Progress in enzymology and molecular biology of SA biosynthesis and metabolism will provide a better understanding of signal transduction pathway involved in plant disease resistance. PMID:11607533

  15. Biosynthesis and metabolism of salicylic acid

    SciTech Connect

    Lee, H.; Leon, J.; Raskin, I.

    1995-05-09

    Pathways of salicylic acid (SA) biosynthesis and metabolism in tobacco have been recently identified. SA, an endogenous regulator of disease resistance, is a product of phenylpropanoid metabolism formed via decarboxylation of trans-cinnamic acid to benzoic acid and its subsequent 2-hydroxylation to SA. In tobacco mosaic virus-inoculated tobacco leaves, newly synthesized SA is rapidly metabolized to SA O-{beta}-D-glucoside and methyl salicylate. Two key enzymes involved in SA biosynthesis and metabolism: benzoic acid 2-hydroxylase, which converts benzoic acid to SA, and UDPglucose:SA glucosyltransferase (EC 2.4.1.35), which catalyzes conversion of SA to SA glucoside have been partially purified and characterized. Progress in enzymology and molecular biology of SA biosynthesis and metabolism will provide a better understanding of signal transduction pathway involved in plant disease resistance. 62 refs., 1 fig.

  16. Induction of salicylic acid (SA) on transcriptional expression of eight carotenoid genes and astaxanthin accumulation in Haematococcus pluvialis.

    PubMed

    Gao, Zhengquan; Meng, Chunxiao; Zhang, Xiaowen; Xu, Dong; Miao, Xuexia; Wang, Yitao; Yang, Liming; Lv, Hongxin; Chen, Lingling; Ye, Naihao

    2012-09-10

    The green alga Haematococcus pluvialis can produce large amounts of pink carotenoid astaxanthin which is a high value ketocarotenoid. In our study, transcriptional expression patterns of eight carotenoid genes in H. pluvialis in response to SA were measured using qRT-PCR. Results indicated that both 25 and 50 mg/L salicylic acid (SA) could increase astaxanthin productivity and enhance transcriptional expression of eight carotenoid genes in H. pluvialis. But these genes exhibited different expression profiles. Moreover, SA25 (25 mg/L SA) induction had a greater effect on the transcriptional expression of ipi-1, psy, pds, crtR-B and lyc (more than 6-fold up-regulation) than on ipi-2, bkt and crtO, but SA50 (50 mg/L SA) treatment had a greater impact on the transcriptional expression of ipi-1, ipi-2, pds, crtR-B and lyc than on psy, bkt and crtO. Furthermore, astaxanthin biosynthesis under SA was up-regulated mainly by ipi-1, ipi-2, psy, crtR-B, bkt and crtO at transcriptional level, lyc at post-transcriptional level and pds at both levels. Summarily, these results suggest that SA constitute molecular signals in the network of astaxanthin biosynthesis. Induction of astaxanthin accumulation by SA without any other stimuli presents an attractive application potential in astaxanthin production with H. pluvialis.

  17. An Arabidopsis thaliana methyltransferase Capable of Methylating Farnesoic Acid

    SciTech Connect

    Yang,Y.; Yuan, J.; Ross, J.; Noel, J.; Pichersky, E.

    2006-01-01

    We previously reported the identification of a new family of plant methyltransferases (MTs), named the SABATH family, that use S-adenosyl-l-methionine (SAM) to methylate a carboxyl moiety or a nitrogen-containing functional group on a diverse array of plant compounds. The Arabidopsis genome alone contains 24 distinct SABATH genes. To identify the catalytic specificities of members of this protein family in Arabidopsis, we screened recombinantly expressed and purified enzymes with a large number of potential substrates. Here, we report that the Arabidopsis thaliana gene At3g44860 encodes a protein with high catalytic specificity towards farnesoic acid (FA). Under steady-state conditions, this farnesoic acid carboxyl methyltransferase (FAMT) exhibits K{sub M} values of 41 and 71 {mu}M for FA and SAM, respectively. A three-dimensional model of FAMT constructed based upon similarity to the experimentally determined structure of Clarkia breweri salicylic acid methyltransferase (SAMT) suggests a reasonable model for FA recognition in the FAMT active site. In plants, the mRNA levels of At3g44860 increase in response to the exogenous addition of several compounds previously shown to induce plant defense responses at the transcriptional level. Although methyl farnesoate (MeFA) has not yet been detected in Arabidopsis, the presence of a FA-specific carboxyl methyltransferase in Arabidopsis capable of producing MeFA, an insect juvenile hormone made by some plants as a presumed defense against insect herbivory, suggests that MeFA or chemically similar compounds are likely to serve as new specialized metabolites in Arabidopsis.

  18. Acid activated montmorillonite as catalysts in methyl esterification reactions of lauric acid.

    PubMed

    Zatta, Leandro; Ramos, Luiz Pereira; Wypych, Fernando

    2012-01-01

    The catalytic activity of acid activated montmorillonite in the esterification of free fatty acids (FFA) is reported. Standard Montmorillonite (MMT) type STx-1 provided by the Clay Mineral Society repository was activated using phosphoric, nitric and sulphuric acids under different conditions and the resulting materials were characterized and evaluated as catalysts in the methyl esterification of lauric acid. Blank reactions carried out in the absence of any added catalyst presented conversions of 32.64, 69.79 and 79.23%, for alcohol:lauric acid molar ratios of 60:1, 12:1 and 6:1, respectively. In the presence of the untreated clay and using molar ratios of 12:1 and 6:1 with 12% of catalyst, conversions of 70.92 and 82.30% were obtained, respectively. For the acid activated clays, conversions up to 93.08% of lauric acid to methyl laurate were obtained, much higher than those observed for the thermal conversion or using untreated montmorillonite. Relative good correlations were observed between the catalytic activity and the development of acid sites and textural properties of the resulting materials. Therefore, a simple acid activation was able to improve the catalytic activity and produce clay catalysts that are environmental friendly, cost effective, noncorrosive and reusable.

  19. Improving the acidic stability of a methyl parathion hydrolase by changing basic residues to acidic residues.

    PubMed

    Huang, Lu; Wang, Ping; Tian, Jian; Jiang, Huachen; Wu, Ningfeng; Yang, Peilong; Yao, Bin; Fan, Yunliu

    2012-06-01

    The acidic stability of a methyl parathion hydrolase (Ochr-MPH) was improved by selectively changing basic amino acids to acidic ones. Mutation sites were selected based on the position-specific amino acid replacement probabilities (more than or equal to 0.2) and the entropy of each site (more than or equal to 0.8). Three mutants (K208E, K277D, and K208E/K277D) were more stable than the wild-type (WT). Their half-lives at pH 5.0 were 64, 68, 65 min, respectively, whereas that of WT was 39 min. The acidic stability of proteins may therefore be improved by changing selected basic amino acid residues to acidic ones.

  20. Photochromic Properties of a Water Soluble Methyl Carboxylic Acid Indolylfulgimide

    PubMed Central

    Chen, Xi; Islamova, Nadezhda I.; Robles, Rachel V.

    2011-01-01

    Photochromic fulgides and fulgimides have been identified as promising materials for applications in optical memory media, optical switches, and sensors. For applications in humid environments or biological systems, hydrolytic stability is crucial. A new photochromic methyl carboxylic acid indolylfulgimide was synthesized to improve hydrolytic stability in aqueous solution. The UV-vis spectra, extinction coefficient, thermal stability, and photochemical stability of the fulgimide were characterized in 50 mM sodium phosphate buffer (pH 7.4). The open and closed forms were both stable in buffer. At 37 °C after 500 h, the open forms of the fulgimide showed no degradation within experimental error (1–2%) by 1H NMR and 2.3% decomposition by UV-vis spectroscopy. The closed form degraded 22% and 11% after 500 h at 37 °C in buffer by UV-vis and 1H NMR data, respectively. In addition, the fulgimide cycled back and forth between the open and closed forms 80 times before degrading by 20% in buffer. The methyl group at the bridging position of the fulgimide significantly increased the thermal stability by overcoming the rapid hydrolysis of the trifluoromethyl group. PMID:21380459

  1. Fatty acid methyl ester profiles of bat wing surface lipids.

    PubMed

    Pannkuk, Evan L; Fuller, Nathan W; Moore, Patrick R; Gilmore, David F; Savary, Brett J; Risch, Thomas S

    2014-11-01

    Sebocytes are specialized epithelial cells that rupture to secrete sebaceous lipids (sebum) across the mammalian integument. Sebum protects the integument from UV radiation, and maintains host microbial communities among other functions. Native glandular sebum is composed primarily of triacylglycerides (TAG) and wax esters (WE). Upon secretion (mature sebum), these lipids combine with minor cellular membrane components comprising total surface lipids. TAG and WE are further cleaved to smaller molecules through oxidation or host enzymatic digestion, resulting in a complex mixture of glycerolipids (e.g., TAG), sterols, unesterified fatty acids (FFA), WE, cholesteryl esters, and squalene comprising surface lipid. We are interested if fatty acid methyl ester (FAME) profiling of bat surface lipid could predict species specificity to the cutaneous fungal disease, white nose syndrome (WNS). We collected sebaceous secretions from 13 bat spp. using Sebutape(®) and converted them to FAME with an acid catalyzed transesterification. We found that Sebutape(®) adhesive patches removed ~6× more total lipid than Sebutape(®) indicator strips. Juvenile eastern red bats (Lasiurus borealis) had significantly higher 18:1 than adults, but 14:0, 16:1, and 20:0 were higher in adults. FAME profiles among several bat species were similar. We concluded that bat surface lipid FAME profiling does not provide a robust model predicting species susceptibility to WNS. However, these results provide baseline data that can be used for lipid roles in future ecological studies, such as life history, diet, or migration.

  2. The preliminary study of autophagy induction of SA and MeSA by confocal

    NASA Astrophysics Data System (ADS)

    Yun, Lijuan; Chen, Wenli

    2010-02-01

    Autophagy appears to be a highly conserved process from unicellular to multicellular eukaryotes which contributes to the equilibrium of intracelluar environment. While it would be harmful to the cells when it is excessive by inducing programmed cell death (PCD). It is a protein degradation process in which cells recycle cytoplasmic contents when subjected to environmental stress conditions or during certain stages of development. Previous studies have demonstrated autophagy can be induced during abiotic or biotic stresses. salicylic acid (SA) and methyl salicytic (MeSA) are endogenous signal molecules. We found SA and MeSA can induce autophagy in Arabidopsis thaliana respectively. While autophagy was not induced by SA or MeSA in tobacco suspension cells under the same concentration and period. The differences in stuctures or physiological states may contribute to the results.

  3. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  4. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  5. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  6. 40 CFR 721.10365 - Butanoic acid, 3-mercapto-2-methyl-, ethyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, ethyl ester. 721.10365 Section 721.10365 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10365 Butanoic acid, 3-mercapto-2-methyl-, ethyl ester. (a) Chemical... acid, 3-mercapto-2-methyl-, ethyl ester (PMN P-10-56; CAS No. 888021-82-7) is subject to...

  7. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  8. 40 CFR 721.10365 - Butanoic acid, 3-mercapto-2-methyl-, ethyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, ethyl ester. 721.10365 Section 721.10365 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10365 Butanoic acid, 3-mercapto-2-methyl-, ethyl ester. (a) Chemical... acid, 3-mercapto-2-methyl-, ethyl ester (PMN P-10-56; CAS No. 888021-82-7) is subject to...

  9. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  10. 40 CFR 721.10365 - Butanoic acid, 3-mercapto-2-methyl-, ethyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, ethyl ester. 721.10365 Section 721.10365 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10365 Butanoic acid, 3-mercapto-2-methyl-, ethyl ester. (a) Chemical... acid, 3-mercapto-2-methyl-, ethyl ester (PMN P-10-56; CAS No. 888021-82-7) is subject to...

  11. 40 CFR 721.2075 - Carbamodithioic acid, methyl-, compound with methanamine (1:1).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-, compound with methanamine (1:1). 721.2075 Section 721.2075 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.2075 Carbamodithioic acid, methyl-, compound with... substance identified generically as carbamodithioic acid, methyl-, compound with methanamine (1:1)...

  12. 40 CFR 721.2075 - Carbamodithioic acid, methyl-, compound with methanamine (1:1).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, compound with methanamine (1:1). 721.2075 Section 721.2075 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.2075 Carbamodithioic acid, methyl-, compound with... substance identified generically as carbamodithioic acid, methyl-, compound with methanamine (1:1)...

  13. 40 CFR 721.2075 - Carbamodithioic acid, methyl-, compound with methanamine (1:1).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, compound with methanamine (1:1). 721.2075 Section 721.2075 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.2075 Carbamodithioic acid, methyl-, compound with... substance identified generically as carbamodithioic acid, methyl-, compound with methanamine (1:1)...

  14. 40 CFR 721.2075 - Carbamodithioic acid, methyl-, compound with methanamine (1:1).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, compound with methanamine (1:1). 721.2075 Section 721.2075 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.2075 Carbamodithioic acid, methyl-, compound with... substance identified generically as carbamodithioic acid, methyl-, compound with methanamine (1:1)...

  15. 40 CFR 721.2075 - Carbamodithioic acid, methyl-, compound with methanamine (1:1).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, compound with methanamine (1:1). 721.2075 Section 721.2075 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.2075 Carbamodithioic acid, methyl-, compound with... substance identified generically as carbamodithioic acid, methyl-, compound with methanamine (1:1)...

  16. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl and ethyl esters of fatty acids produced... Methyl and ethyl esters of fatty acids produced from edible fats and oils. Methyl esters and ethyl esters... following prescribed conditions: (a) The additive consists of a mixture of either methyl or ethyl esters...

  17. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Methyl and ethyl esters of fatty acids produced... Methyl and ethyl esters of fatty acids produced from edible fats and oils. Methyl esters and ethyl esters... following prescribed conditions: (a) The additive consists of a mixture of either methyl or ethyl esters...

  18. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Methyl and ethyl esters of fatty acids produced... Methyl and ethyl esters of fatty acids produced from edible fats and oils. Methyl esters and ethyl esters... following prescribed conditions: (a) The additive consists of a mixture of either methyl or ethyl esters...

  19. Lewis acid assisted methyl/chlorine exchange in silylated hydrazinochlorophosphanes.

    PubMed

    Westenkirchner, Andrea; Villinger, Alexander; Karaghiosoff, Konstantin; Wustrack, Ronald; Michalik, Dirk; Schulz, Axel

    2011-03-21

    Differently substituted hydrazinophosphanes of the type (Me(3)Si)(2)N-N(SiMe(3))-PR(1)R(2) (R(1) = Cl with R(2) = Me, C(6)F(5) and R(1) = Me, R(2) = C(6)H(5)) have been studied in the reaction with Lewis acids such as ECl(3) (E = Al, Ga). For (Me(3)Si)(2)N-N(SiMe(3))-P(Cl)(Me) and (Me(3)Si)(2)N-N(SiMe(3))-P(Me)(C(6)H(5)), only adduct formation was found while a chlorine/methyl exchange reaction was observed for (Me(3)Si)(2)N-N(SiMe(3))-P(Cl)R (R = C(6)H(5) and C(6)F(5)) leading to the formation of (Me(2)ClSi)(Me(3)Si)N-N(SiMe(3))-P(Me)R, which crystallize as ECl(3) adducts. The free hydrazinophosphanes can be obtained by removal of the Lewis acid with the help of a strong base such as 4-(dimethylamino)pyridine (DMAP).

  20. Studies of the acidic components of the Colorado Green River formation oil shale-Mass spectrometric identification of the methyl esters of extractable acids.

    NASA Technical Reports Server (NTRS)

    Haug, P.; Schnoes, H. K.; Burlingame, A. L.

    1971-01-01

    Study of solvent extractable acidic constituents of oil shale from the Colorado Green River Formation. Identification of individual components is based on gas chromatographic and mass spectrometric data obtained for their respective methyl esters. Normal acids, isoprenoidal acids, alpha, omega-dicarboxylic acids, mono-alpha-methyl dicarboxylic acids and methyl ketoacids were identified. In addition, the presence of monocyclic, benzoic, phenylalkanoic and naphthyl-carboxylic acids, as well as cycloaromatic acids, is demonstrated by partial identification.

  1. PLASMID DNA DAMAGE CAUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    EPA Science Inventory

    PLASMID DNA DAMAGE CAOUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    ABSTRACT

    Both dimethylarsinic acid (DMA(V)) and dimethylarsinous acid (DMA(III)) release iron from human liver ferritin (HLF) with or without the presence of ascorbic acid. ...

  2. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  3. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  4. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  5. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  6. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  7. Methyl esters from vegetable oils with hydroxy fatty acids: Comparison of lesquerella and castor methyl esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The search for alternative feedstocks for biodiesel as partial replacement for petrodiesel has recently extended to castor oil. In this work, the castor oil methyl esters were prepared and their properties determined in comparison to the methyl esters of lesquerella oil, which in turn is seen as alt...

  8. Methylation of deoxyribonucleic acid in cultured mammalian cells by N-methyl-N′-nitro-N-nitrosoguanidine. The influence of cellular thiol concentrations on the extent of methylation and the 6-oxygen atom of guanine as a site of methylation

    PubMed Central

    Lawley, P. D.; Thatcher, Carolyn J.

    1970-01-01

    1. In neutral aqueous solution N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) yields salts of nitrocyanamide as u.v.-absorbing products. With cysteine, as found independently by Schulz & McCalla (1969), the principal product is 2-nitràminothiazoline-4-carboxylic acid. Both these reactions liberate the methylating species; thiols enhance the rate markedly at neutral pH values. An alternative reaction with thiols gives cystine, presumably via the unstable S-nitrosocysteine. 2. Thiols (glutathione or N-acetylcysteine) in vitro at about the concentration found in mammalian cells enhance the rate of methylation of DNA markedly over that in neutral solution. 3. Treatment of cultured mammalian cells with MNNG results in rapid methylation of nucleic acids, the extent being greater the higher the thiol content of the cells. Rodent embryo cells are more extensively methylated than mouse L-cells of the same thiol content. Cellular thiol concentrations are decreased by MNNG. Proteins are less methylated by MNNG than are nucleic acids. 4. Methylation of cells by dimethyl sulphate does not depend on cellular thiol content and protein is not less methylated than nucleic acids. Methylation by MNNG may therefore be thiol-stimulated in cells. 5. Both in vitro and in cells about 7% of the methylation of DNA by MNNG occurs at the 6-oxygen atom of guanine. The major products 7-methylguanine and 3-methyladenine are given by both MNNG and dimethyl sulphate, but dimethyl sulphate does not yield O6-methylguanine. Possible reaction mechanisms to account for this difference between these methylating agents and its possible significance as a determinant of their biological effects are discussed. PMID:5435496

  9. A relationship between vitamin B sub 12 , folic acid, ascorbic acid, and mercury uptake and methylation

    SciTech Connect

    Zorn, N.E.; Smith, J.T. )

    1990-01-01

    Ingestion of megadoses of certain vitamins appears to influence the in vivo methylation of mercuric chloride in guinea pigs. The addition of megadoses of vitamin B{sub 12} fed either singularly or in combination with folic acid resulted in increased methylmercury concentrations in the liver. Moreover, percent methylmercury levels were significantly increased with B{sub 12} treatment in the liver (B{sub 12} only and B{sub 12}/folic acid) and brain (B{sub 12}/vitamin C). Incorporation of high levels of folic acid into the dietary regime also increased the methylmercury concentration particularly in the liver and hair tissues. The addition of vitamin C in the diet, particularly in combination with B{sub 12} (brain) or folic acid (muscle) resulted in increased methylmercury levels in these tissues and percent methylmercury values with B{sub 12} in the muscle and brain tissue.

  10. 75 FR 50926 - 2-propenoic acid, 2-methyl-, C12-16-alkyl esters, telomers with 1-dodecanethiol, polyethylene...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... AGENCY 40 CFR Part 180 2-propenoic acid, 2-methyl-, C12-16-alkyl esters, telomers with 1-dodecanethiol... tolerance for residues of 2-propenoic acid, 2-methyl-, C12-16- alkyl esters, telomers with 1-dodecanethiol... residues of 2-propenoic acid, 2-methyl-, C12-16-alkyl esters, telomers with 1-dodecanethiol,...

  11. [Neuroepigenetics: Desoxyribonucleic acid methylation in Alzheimer's disease and other dementias].

    PubMed

    Mendioroz Iriarte, Maite; Pulido Fontes, Laura; Méndez-López, Iván

    2015-05-21

    DNA methylation is an epigenetic mechanism that controls gene expression. In Alzheimer's disease (AD), global DNA hypomethylation of neurons has been described in the human cerebral cortex. Moreover, several variants in the methylation pattern of candidate genes have been identified in brain tissue when comparing AD patients and controls. Specifically, DNA methylation changes have been observed in PSEN1 and APOE, both genes previously being involved in the pathophysiology of AD. In other degenerative dementias, methylation variants have also been described in key genes, such as hypomethylation of the SNCA gene in Parkinson's disease and dementia with Lewy bodies or hypermethylation of the GRN gene promoter in frontotemporal dementia. The finding of aberrant DNA methylation patterns shared by brain tissue and peripheral blood opens the door to use those variants as epigenetic biomarkers in the diagnosis of neurodegenerative diseases.

  12. Total synthesis of (±)-epithuriferic acid methyl ester via Diels-Alder reaction.

    PubMed

    Koprowski, Marek; Bałczewski, Piotr; Owsianik, Krzysztof; Różycka-Sokołowska, Ewa; Marciniak, Bernard

    2016-02-07

    In this paper, we have described the first total synthesis of (±)-epithuriferic acid methyl ester from non-natural sources, in four steps (20% overall yield). The key step involves the Diels-Alder reaction of isobenzofuran with methyl 3-(dimethoxyphosphoryl)acrylate which is controlled by "ortho" regio- and endo stereoselectivities due to the COOMe group.

  13. Chemically modified fatty acid methyl esters: their potential for use as lubrication fluids and surfactants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A review of recent developments in the synthesis and characterization of lubrication fluids and surfactants from methyl oleate. The synthesis of materials made using an epoxidation route is the focus. This versatile method of chemical modification of fatty acid methyl esters improves their oxidati...

  14. An efficient preparation of N-methyl-alpha-amino acids from N-nosyl-alpha-amino acid phenacyl esters.

    PubMed

    Leggio, Antonella; Belsito, Emilia Lucia; De Marco, Rosaria; Liguori, Angelo; Perri, Francesca; Viscomi, Maria Caterina

    2010-03-05

    In this paper we describe a simple and efficient solution-phase synthesis of N-methyl-N-nosyl-alpha-amino acids and N-Fmoc-N-methyl-alpha-amino acids. This represents a very important application in peptide synthesis to obtain N-methylated peptides in both solution and solid phase. The developed methodology involves the use of N-nosyl-alpha-amino acids with the carboxyl function protected as a phenacyl ester and the methylating reagent diazomethane. An important aspect of this synthetic strategy is the possibility to selectively deprotect the carboxyl function or alternatively both amino and carboxyl moieties by using the same reagent with a different molar excess and under mild conditions. Furthermore, the adopted procedure keeps unchanged the acid-sensitive side chain protecting groups used in Fmoc-based synthetic strategies.

  15. Spectroscopic and quantum chemical analysis of Isonicotinic acid methyl ester

    NASA Astrophysics Data System (ADS)

    Shoba, D.; Periandy, S.; Govindarajan, M.; Gayathri, P.

    2015-02-01

    In this present study, an organic compound Isonicotinic acid methyl ester (INAME) was structurally characterized by FTIR, FT-Raman, and NMR and UV spectroscopy. The optimized geometrical parameters and energies of all different and possible conformers of INAME are obtained from Density Functional Theory (DFT) by B3LYP/6-311++G(d,p) method. There are three conformers (SI, SII-1, and SII-2) for this molecule (ground state). The most stable conformer of INAME is SI conformer. The molecular geometry and vibrational frequencies of INAME in the ground state have been calculated by using HF and density functional method (B3LYP) 6-311++G (d,p) basis set. Detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The computed vibrational frequencies were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. A study on the electronic properties, such as HOMO and LUMO energies were performed by time independent DFT approach. Besides, molecular electrostatic potential (MEP) and thermodynamic properties were performed. The electric dipole moment (μ) and first hyper polarizability (β) values of the investigated molecule were computed using ab initio quantum mechanical calculations. The calculated results show that the INAME molecule may have microscopic nonlinear optical (NLO) behavior with non zero values. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by gauge independent atomic orbital (GIAO) method.

  16. 8-Methoxypsoralen-nucleic acid photoreaction. Effect of methyl substitution on pyrone vs. furan photoaddition

    SciTech Connect

    Kanne, D.; Rapoport, H.; Hearst, J.E.

    1984-04-01

    We have synthesized a series of 8-(3H)methoxypsoralens in which methyl and hydrogen are systematically varied at the 4- and 5'-positions. Analysis of the products resulting from the photoaddition of these four psoralens with the nucleic acid poly(dA-dT) reveals that the product distribution depends on the presence or absence of a 4-methyl substituent. Compounds with the 4-methyl group show an overwhelming preference (approximately 98%) for addition to the furan double bond, while compounds without the 4-methyl show a substantial amount (approximately 18%) of addition to the pyrone double bond.

  17. AVOIDING PITFALLS IN THE DETERMINATION OF HALOCARBOXYLIC ACIDS: THE PHOTOCHEMISTRY OF METHYLATION

    EPA Science Inventory

    Haloethanoic (haloacetic) acids are formed during chlorination of drinking water and are regulated by the Environmental Protection Agency (EPA). These compounds are normally quantified by gas chromatography with electron capture detection (GC-ECD) ad the methyl esters. EPA Meth...

  18. Design and biological properties of iodine-123 labeled. beta. -methyl-branched fatty acids

    SciTech Connect

    Knapp, F.F. Jr.; Goodman, M.M.

    1984-01-01

    The synthetic strategy, synthesis, preclinical evaluation and potential clinical applications of 3-methyl-branched radioiodinated iodophenyl- and iodovinyl-substituted fatty acids are reviewed for use as myocardial imaging agents. 50 references, 6 figures. (ACR)

  19. 40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzoic acid,...

  20. 40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzoic acid,...

  1. 40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzoic acid,...

  2. 40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzoic acid,...

  3. 40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzoic acid,...

  4. Preparation of fatty acid methyl esters from Osage orange (Maclura pomifera) oil and evaluation as biodiesel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid methyl esters were prepared in high yield by transesterification of Osage orange (Maclura pomifera) oil. Extracted using supercritical CO2, the crude oil was initially treated with mineral acid and methanol to lower its content of free fatty acids, thus rendering it amenable to homogeneou...

  5. 75 FR 78243 - Propionic Acid and Salts, Urea Sulfate, Methidathion, and Methyl Parathion; Registration Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-15

    ... AGENCY Propionic Acid and Salts, Urea Sulfate, Methidathion, and Methyl Parathion; Registration Review... pesticides propionic acid and salts, case no. 4078, urea sulfate, case no. 7213, methidathion, case no. 0034... pesticides in the table below--propionic acid and salts, case 4078, urea sulfate, case no. 7213,...

  6. 75 FR 770 - Acrylic acid-benzyl methacrylate-1-propanesulfonic acid, 2-methyl-2-[(1-oxo-2-propenyl)amino...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-06

    ... AGENCY 40 CFR Part 180 Acrylic acid-benzyl methacrylate-1-propanesulfonic acid, 2- methyl-2... residues of acrylic acid-benzyl methacrylate-1- propanesulfonic acid, 2-methyl-2- -, monosodium salt... to establish a maximum permissible level for residues of acrylic acid-benzyl...

  7. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  8. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  9. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  10. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  11. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  12. Associations between whole peripheral blood fatty acids and DNA methylation in humans

    PubMed Central

    de la Rocha, Carmen; Pérez-Mojica, J. Eduardo; León, Silvia Zenteno-De; Cervantes-Paz, Braulio; Tristán-Flores, Fabiola E.; Rodríguez-Ríos, Dalia; Molina-Torres, Jorge; Ramírez-Chávez, Enrique; Alvarado-Caudillo, Yolanda; Carmona, F. Javier; Esteller, Manel; Hernández-Rivas, Rosaura; Wrobel, Katarzyna; Wrobel, Kazimierz; Zaina, Silvio; Lund, Gertrud

    2016-01-01

    Fatty acids (FA) modify DNA methylation in vitro, but limited information is available on whether corresponding associations exist in vivo and reflect any short-term effect of the diet. Associations between global DNA methylation and FAs were sought in blood from lactating infants (LI; n = 49) and adult males (AMM; n = 12) equally distributed across the three conventional BMI classes. AMM provided multiple samples at 2-hour intervals during 8 hours after either a single Western diet-representative meal (post-prandial samples) or no meal (fasting samples). Lipid/glucose profile, HDAC4 promoter and PDK4 5’UTR methylation were determined in AMM. Multiple regression analysis revealed that global (in LI) and both global and PDK4-specific DNA methylation (in AMM) were positively associated with eicosapentaenoic and arachidonic acid. HDAC4 methylation was inversely associated with arachidonic acid post-prandially in AMM. Global DNA methylation did not show any defined within-day pattern that would suggest a short-term response to the diet. Nonetheless, global DNA methylation was higher in normal weight subjects both post-prandially and in fasting and coincided with higher polyunsaturated relative to monounsaturated and saturated FAs. We show for the first time strong associations of DNA methylation with specific FAs in two human cohorts of distinct age, diet and postnatal development stage. PMID:27181711

  13. 40 CFR 721.4097 - 7-Oxabicyclo[4.1.0]heptane-3-carboxylic acid, methyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., methyl ester. 721.4097 Section 721.4097 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.4097 7-Oxabicyclo heptane-3-carboxylic acid, methyl ester. (a) Chemical...-oxabicyclo heptane-3-carboxylic acid, methyl ester (PMN P-98-101) is subject to reporting under this...

  14. 40 CFR 721.4097 - 7-Oxabicyclo[4.1.0]heptane-3-carboxylic acid, methyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., methyl ester. 721.4097 Section 721.4097 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.4097 7-Oxabicyclo heptane-3-carboxylic acid, methyl ester. (a) Chemical...-oxabicyclo heptane-3-carboxylic acid, methyl ester (PMN P-98-101) is subject to reporting under this...

  15. How to identify and discriminate between the methyl quinates of chlorogenic acids by liquid chromatography-tandem mass spectrometry.

    PubMed

    Jaiswal, Rakesh; Kuhnert, Nikolai

    2011-03-01

    The methyl esters of chlorogenic acids, methyl quinates, are widely distributed in plant materials and frequently appear as extraction artifacts in plant samples. This is the first time when liquid chromatography-tandem mass spectrometry methods have been used for the identification and characterization of the methyl quinates. For this purpose, methyl quinates of mono caffeoylquinic acids and mono feruloylquinic acids were synthesized as authentic standards. The methyl quinates of mono and diacyl chlorogenic acids have shown characteristic fragmentation pattern in their tandem mass spectra. MS(n + 1) spectra of the methyl quinates of diacyl chlorogenic acids were identical to MS(n) spectra of mono acyl derivatives. These quinates do not produce any methyl quinate peak at m/z 205 if compared with quinic acid peak at m/z 191 in negative ion mode. In the MS(n) spectra of these quinates, cinnamic acid part or cinnamoyl part was detected as a base peak in negative ion mode. The retention time, order of elution and fragmentation pattern were completely different if compared with LC-MS(n) methods developed for chlorogenic acids. These LC-MS(n) methods have been applied for the identification and regioisomeric characterization of the methyl quinates of chlorogenic acids in maté tea and woodruff (Galium odoratum). Two methyl caffeoylquinates (2 and 4) were identified as methyl 3-caffeoylquinate and methyl 5-caffeoylquinate.

  16. Proton affinity of methyl nitrate - Less than proton affinity of nitric acid

    NASA Technical Reports Server (NTRS)

    Lee, Timothy J.; Rice, Julia E.

    1992-01-01

    Several state-of-the-art ab initio quantum mechanical methods were used to investigate the equilibrium structure, dipole moments, harmonic vibrational frequencies, and IR intensities of methyl nitrate, methanol, and several structures of protonated methyl nitrate, using the same theoretical methods as in an earlier study (Lee and Rice, 1992) of nitric acid. The ab initio results for methyl nitrate and methanol were found to be in good agreement with available experimental data. The proton affinity (PA) of methyl nitrate was calculated to be 176.9 +/-5 kcal/mol, in excellent agreement with the experimental value 176 kcal/mol obtained by Attina et al. (1987) and less than the PA value of nitric acid. An explanation of the discrepancy of the present results with those of an earlier study on protonated nitric acid is proposed.

  17. Uptake of isoprene, methacrylic acid and methyl methacrylate into aqueous solutions of sulfuric acid and hydrogen peroxide.

    PubMed

    Liu, Ze; Ge, Maofa; Wang, Weigang

    2012-01-01

    Multiphase acid-catalyzed oxidation by hydrogen peroxide has been suggested to be a potential route to secondary organic aerosol formation from isoprene and its gas-phase oxidation products, but the lack of kinetics data significantly limited the evaluation of this process in the atmosphere. Here we report the first measurement of the uptake of isoprene, methacrylic acid and methyl methacrylate into aqueous solutions of sulfuric acid and hydrogen peroxide. Isoprene cannot readily partition into the solution because of its high volatility and low solubility, which hinders its further liquid-phase oxidation. Both methacrylic acid and methyl methacrylate can enter the solutions and be oxidized by hydrogen peroxide, and steady-state uptake was observed with the acidity of solution above 30 wt.% and 70 wt.%, respectively. The steady-state uptake coefficient of methacrylic acid is much larger than that of methyl methacrylate for a solution with same acidity. These observations can be explained by the different reactivity of these two compounds caused by the different electron-withdrawing conjugation between carboxyl and ester groups. The atmospheric lifetimes were estimated based on the calculated steady-state uptake coefficients. These results demonstrate that the multiphase acid-catalyzed oxidation of methacrylic acid plays a role in secondary organic aerosol formation, but for isoprene and methyl methacrylate, this process is not important in the troposphere.

  18. Biosorption of methyl blue onto tartaric acid modified wheat bran from aqueous solution.

    PubMed

    Yao, Shuhua; Lai, Hong; Shi, Zhongliang

    2012-12-05

    Tartaric acid modified wheat bran was utilized as adsorbent to remove methyl blue, a basic dye from aqueous solution. Batch experiments were carried out to study the effect of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage, on dye adsorption. The results showed that the modification of wheat bran by tartaric acid significantly improved its adsorption capacity, and made this material a suitable adsorbent to remove methyl blue. The adsorption capacity of modified wheat bran was about 1.6 times higher than that of unmodified one. The amount of methyl blue adsorbed was found to vary with initial solution pH, adsorbent dosage, contact time and initial methyl blue concentration. Kinetics study showed that the overall adsorption rate of methyl blue was illustrated by pseudo-second-order kinetic model. The applicability of the Langmuir and Freundlich models for the data was tested. Both models adequately described the experimental data of the biosorption of methyl blue. The maximum adsorption capacity for methyl blue calculated from Langmuir model was 25.18 mg/g. The study has shown the effectiveness of modified wheat bran in the removal of methyl blue, and that it can be considered as an attractive alternative to the more expensive technologies used in wastewater treatment.

  19. Biosorption of methyl blue onto tartaric acid modified wheat bran from aqueous solution

    PubMed Central

    2012-01-01

    Tartaric acid modified wheat bran was utilized as adsorbent to remove methyl blue, a basic dye from aqueous solution. Batch experiments were carried out to study the effect of various experimental parameters such as initial solution pH, contact time, initial dye concentration and adsorbent dosage, on dye adsorption. The results showed that the modification of wheat bran by tartaric acid significantly improved its adsorption capacity, and made this material a suitable adsorbent to remove methyl blue. The adsorption capacity of modified wheat bran was about 1.6 times higher than that of unmodified one. The amount of methyl blue adsorbed was found to vary with initial solution pH, adsorbent dosage, contact time and initial methyl blue concentration. Kinetics study showed that the overall adsorption rate of methyl blue was illustrated by pseudo-second-order kinetic model. The applicability of the Langmuir and Freundlich models for the data was tested. Both models adequately described the experimental data of the biosorption of methyl blue. The maximum adsorption capacity for methyl blue calculated from Langmuir model was 25.18 mg/g. The study has shown the effectiveness of modified wheat bran in the removal of methyl blue, and that it can be considered as an attractive alternative to the more expensive technologies used in wastewater treatment. PMID:23369295

  20. Inactivation of the WNT5A Alternative Promoter B Is Associated with DNA Methylation and Histone Modification in Osteosarcoma Cell Lines U2OS and SaOS-2.

    PubMed

    Vaidya, Himani; Rumph, Candie; Katula, Karen S

    2016-01-01

    WNT5A is a secreted ligand involved in Wnt pathway signaling and has a role in cell movement and differentiation. Altered WNT5A expression is associated with various cancers, although in most studies the focus has been on only one of the known WNT5A isoforms. In this study, we analyzed expression from two of the major WNT5A promoters, termed promoter A and promoter B, in normal human osteoblasts, SaOS-2 and U2OS osteosarcoma cell lines, and osteosarcoma tumor tissue. We found that both promoters A and B are active in normal osteoblasts with nearly 11-fold more promoter B than A transcripts. Promoter B but not promoter A transcripts are decreased or nearly undetectable in the SaOS-2 and U2OS cell lines and osteosarcoma tumor tissues. Transient transfection of promoter A and promoter B reporter constructs confirmed that SaOS-2 cells have the necessary factors to transcribe both promoters. Bisulfite sequencing analysis revealed that three CpG enriched regions upstream of the promoter B exon 1βare highly methylated in both SaOS-2 and U2OS cells. The CpG island sub-region R6 located in promoter B exon 1β was approximately 51% methylated in SaOS-2 and 25% methylated in U2OS. Region 3 was approximately 28% methylated in normal osteoblasts, whereas the others were unmethylated. Promoter B was re-activated by treatment of SaOS-2 cells with 1 μM 5-azacytidine, which was associated with only a small insignificant change in methylation of sub-region R6. ChIP analysis of U2OS and SaOS-2 cells indicated that the promoter B region is less enriched in the active histone mark H3K4me3, in comparison to promoter A and that there is increased enrichment of the repressive mark H3K27me3 in association with the promoter B genomic region in the cell line SaOS-2. These findings show that epigenetic inactivation of the WNT5A promoter B involves both DNA methylation and histone modifications and suggest that differential expression of the WNT5A alternative promoters A and B is a

  1. Characterization of N-methylated amino acids by GC-MS after ethyl chloroformate derivatization.

    PubMed

    Reddy, B Sudarshana; Chary, V Naresh; Pavankumar, P; Prabhakar, S

    2016-08-01

    Methylation is an essential metabolic process in the biological systems, and it is significant for several biological reactions in living organisms. Methylated compounds are known to be involved in most of the bodily functions, and some of them serve as biomarkers. Theoretically, all α-amino acids can be methylated, and it is possible to encounter them in most animal/plant samples. But the analytical data, especially the mass spectral data, are available only for a few of the methylated amino acids. Thus, it is essential to generate mass spectral data and to develop mass spectrometry methods for the identification of all possible methylated amino acids for future metabolomic studies. In this study, all N-methyl and N,N-dimethyl amino acids were synthesized by the methylation of α-amino acids and characterized by a GC-MS method. The methylated amino acids were derivatized with ethyl chloroformate and analyzed by GC-MS under EI and methane/CI conditions. The EI mass spectra of ethyl chloroformate derivatives of N-methyl (1-18) and N,N-dimethyl amino acids (19-35) showed abundant [M-COOC2 H5 ](+) ions. The fragment ions due to loss of C2 H4 , CO2 , (CO2  + C2 H4 ) from [M-COOC2 H5 ](+) were of structure indicative for 1-18. The EI spectra of 19-35 showed less number of fragment ions when compared with those of 1-18. The side chain group (R) caused specific fragment ions characteristic to its structure. The methane/CI spectra of the studied compounds showed [M + H](+) ions to substantiate their molecular weights. The detected EI fragment ions were characteristic of the structure that made easy identification of the studied compounds, including isomeric/isobaric compounds. Fragmentation patterns of the studied compounds (1-35) were confirmed by high-resolution mass spectra data and further substantiated by the data obtained from (13) C2 -labeled glycines and N-ethoxycarbonyl methoxy esters. The method was applied to human plasma samples for the identification

  2. Quantification of primary fatty acid amides in commercial tallow and tallow fatty acid methyl esters by HPLC-APCI-MS.

    PubMed

    Madl, Tobias; Mittelbach, Martin

    2005-04-01

    Primary fatty acid amides are a group of biologically highly active compounds which were already identified in nature. Here, these substances were determined in tallow and tallow fatty acid methyl esters for the first time. As tallow is growing in importance as an oleochemical feedstock for the soap manufacturing, the surfactant as well as the biodiesel industry, the amounts of primary fatty acid amides have to be considered. As these compounds are insoluble in tallow as well as in the corresponding product e.g. tallow fatty acid methyl esters, filter plugging can occur. For the quantification in these matrices a purification step and a LC-APCI-MS method were developed. Although quantification of these compounds can be performed by GC-MS, the presented approach omitted any derivatization and increased the sensitivity by two orders of magnitude. Internal standard calibration using heptadecanoic acid amide and validation of the method yielded a limit of detection of 18.5 fmol and recoveries for the tallow and fatty acid methyl ester matrices of 93% and 95%, respectively. A group of commercially available samples were investigated for their content of fatty acid amides resulting in an amount of up to 0.54%m/m (g per 100 g) in tallow and up to 0.16%m/m (g per 100 g) in fatty acid methyl esters.

  3. Methyl-branched poly(hydroxyalkanoate) biosynthesis from 13- methyltetradecanoic acid and mixed isostearic acid isomer substrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas resinovorans, a known medium-chain-length (mcl-) poly(hydroxyalkanoate) (PHA) producer, was grown on 13-methyltetradecanoic acid (13-MTDA) and a mixture of isostearic acid (IA) isomers to produce methyl-branched mcl-PHA polymers. Shake flask experiments revealed polymer productivities (...

  4. Actinomycin synthesis in Streptomyces antibioticus: enzymatic conversion of 3-Hydroxyanthranilic acid to 4-methyl-3-hydroxyanthranilic acid

    SciTech Connect

    Jones, G.H.

    1987-12-01

    A methyltransferase with utilizes 3-hydroxyanthranilic acid (HAA) as a substrate was identified in detergent-treated extracts of the bacterium Streptomyces antibioticus. The enzyme catalyzes the transfer of methyl groups from (/sup 14/C)S-adenosylmethionine to HAA, but does not catalyze the methylation of 3-hydroxy-DL-kynurenine. Enzyme, substrate, time, and pH dependencies for the methyl transfer reaction were examined. Reaction products obtained from scaled-up reaction mixtures were fractionated by chromatography on Dowex 1, and the Dowex 1 fractions were examined by paper and thin-layer chromatography. One Dowex fraction was shown to contain a radioactive product with the chromatographic properties of 4-methyl-3-hydroxyanthranilic acid (MHA), a known intermediate in the biosynthesis of actinomycin. Available evidence indicates that the conversion of HAA to MHA is an early step in the biosynthesis of actinomycin by S. antibioticus and other actinomycin-producing streptomycetes.

  5. Alternative fuel properties of tall oil fatty acid methyl ester-diesel fuel blends.

    PubMed

    Altiparmak, Duran; Keskin, Ali; Koca, Atilla; Gürü, Metin

    2007-01-01

    In this experimental work, tall oil methyl ester-diesel fuel blends as alternative fuels for diesel engines were studied. Tall oil methyl ester was produced by reacting tall oil fatty acids with methyl alcohol under optimum conditions. The blends of tall oil methyl ester-diesel fuel were tested in a direct injection diesel engine at full load condition. The effects of the new fuel blends on the engine performance and exhaust emission were tested. It was observed that the engine torque and power output with tall oil methyl ester-diesel fuel blends increased up to 6.1% and 5.9%, respectively. It was also seen that CO emissions decreased to 38.9% and NO(x) emissions increased up to 30% with the new fuel blends. The smoke opacity did not vary significantly.

  6. Coriander Seed Oil Methyl Esters as Biodiesel Fuel: Unique Fatty Acid Composition and Excellent Oxidative Stability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coriander (Coriandrum sativum L.) seed oil methyl esters were prepared and evaluated as an alternative biodiesel fuel and contained an unusual fatty acid (FA) hitherto unreported as the principle component in biodiesel fuels: petroselinic (6Z-octadecenoic; 68.5 wt %) acid. Most of the remaining FA...

  7. Selective microbial degradation of saturated methyl branched chain fatty acid isomers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three strains of Pseudomonas bacteria were screened for their capabilities of degrading chemically synthesized saturated branched-chain fatty acids (sbc-FAs). Mixtures of sbc-FAs with the methyl-branch located at various locales along the fatty acid were used as a carbon feedstock in shake-flask cu...

  8. Low-temperature phase behavior of fatty acid methyl esters by differential scanning calorimetry (DSC)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid methyl ester (FAME) mixtures have many uses including biodiesel, lubricants, metal-working fluids, surfactants, polymers, coatings, green solvents and phase-change materials. The physical properties of a FAME mixture depends on the fatty acid concentration (FAC) profile. Some products hav...

  9. DNA methylation landscape of fat deposits and fatty acid composition in obese and lean pigs

    PubMed Central

    Zhang, Shunhua; Shen, Linyuan; Xia, Yudong; Yang, Qiong; Li, Xuewei; Tang, Guoqing; Jiang, Yanzhi; Wang, Jinyong; Li, Mingzhou; Zhu, Li

    2016-01-01

    Obese and lean type pig breeds exhibit differences in their fat deposits and fatty acid composition. Here, we compared the effect of genome-wide DNA methylation on fatty acid metabolism between Landrace pigs (LP, leaner) and Rongchang pigs (RP, fatty). We found that LP backfat (LBF) had a higher polyunsaturated fatty acid content but a lower adipocyte volume than RP backfat (RBF). LBF exhibited higher global DNA methylation levels at the genome level than RBF. A total of 483 differentially methylated regions (DMRs) were located in promoter regions, mainly affecting olfactory and sensory activity and lipid metabolism. In LBF, the promoters of genes related to ATPase activity had significantly stronger methylation. This fact may suggest lower energy metabolism levels, which may result in less efficient lipid synthesis in LBF. Furthermore, we identified a DMR in the miR-4335 and miR-378 promoters and validated their methylation status by bisulfite sequencing PCR. The hypermethylation of the promoters of miR-4335 and miR-378 in LBF and the resulting silencing of the target genes may result in LBF’s low content in saturated fatty acids and fat deposition capacity. This study provides a solid basis for exploring the epigenetic mechanisms affecting fat deposition and fatty acid composition. PMID:27721392

  10. Molecular weight determination of methyl esters of mycolic acids using thermospray mass spectrometry.

    PubMed

    Ioneda, T; Beaman, B L

    1992-11-01

    Methyl esters of normal fatty acids, corynomycolate and corynomycolenate were used as model compounds for thermospray mass spectrometric procedures for molecular weight determination of the related nocardial mycolic acids. By using ammonium acetate at the positive ion generator, in both cases, a family of ions was produced. The following members were found and corresponded to the adducts: (1) M + H; M + NH4 and M + H + NH4 for methyl esters of normal fatty acids, whereas M + H, M + 2H and M + H + NH4 were the adducts most frequently observed with methyl corynomycolates. The methyl esters of C40-C48 mycolic acids from Rhodococcus rhodochrous exhibited prominent peaks corresponding to adducts M + H + NH4 whereas those corresponding to M + 2H showed slightly lower intensities. The structure M + H had no significant representatives with this subclass of mycolic acids. A similar pattern was observed with methyl esters of C50-C54 mycolic acids from Nocardia asteroides GUH-2. Ion peaks C50-C54 representing adducts M + 2H and M + H + NH4 prevailed in the mass spectrum. In this case, the intensities of peaks corresponding to M + 2H were slightly higher than those of the M + H + NH4. Essentially three main species of nocardomycolic acids were detected: (1) monounsaturated C50:1, C52:1 and C54:1; (2) diunsaturated C50:2, C52:2 and C54:2 and (3) triunsaturated C52:3 and C54:3 mycolic acids. The most abundant mycolic acid was C52:2 followed in decreasing abundance by C52:1, C54:2, C50:2, C52:3 and C54:3 mycolic acids.

  11. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acetic acid, , 1-methyl hexyl ester... Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  12. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acetic acid, , 1-methyl hexyl ester... Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  13. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Acetic acid, , 1-methyl hexyl ester... Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  14. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Acetic acid, , 1-methyl hexyl ester... Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  15. 40 CFR 721.304 - Acetic acid, [(5-chloro-8-quinolinyl)oxy-], 1-methyl hexyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Acetic acid, , 1-methyl hexyl ester... Substances § 721.304 Acetic acid, , 1-methyl hexyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as acetic acid, -, 1-methylhexyl ester (PMN...

  16. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  17. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  18. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  19. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  20. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  1. The Acid Catalyzed Nitration of Methanol: Formation of Methyl Nitrate via Aerosol Chemistry

    NASA Technical Reports Server (NTRS)

    Riffel, Brent G.; Michelsen, Rebecca R.; Iraci, Laura T.

    2004-01-01

    The liquid phase acid catalyzed reaction of methanol with nitric acid to yield methyl nitrate under atmospheric conditions has been investigated using gas phase infrared spectroscopy. This nitration reaction is expected to occur in acidic aerosol particles found in the upper troposphere/lower stratosphere as highly soluble methanol and nitric acid diffuse into these aerosols. Gaseous methyl nitrate is released upon formation, suggesting that some fraction of NO(x) may he liberated from nitric acid (methyl nitrate is later photolyzed to NO(x)) before it is removed from the atmosphere by wet deposition. Thus, this reaction may have important implications for the NO(x) budget. Reactions have been initiated in 45-62 wt% H2SO4 solutions at 10.0 C. Methyl nitrate production rates increased exponentially with acidity within the acidity regime studied. Preliminary calculations suggest that the nitronium ion (NO2(+) is the active nitrating agent under these conditions. The reaction order in methanol appears to depend on the water/methanol ratio and varies from first to zeroth order under conditions investigated. The nitration is first order in nitronium at all acidities investigated. A second order rate constant, kappa(sub 2), has been calculated to be 1 x 10(exp 8)/ M s when the reaction is first order in methanol. Calculations suggest the nitration is first order in methanol under tropospheric conditions. The infinitesimal percentage of nitric acid in the nitronium ion form in this acidity regime probably makes this reaction insignificant for the upper troposphere; however, this nitration may become significant in the mid stratosphere where colder temperatures increase nitric acid solubility and higher sulfuric acid content shifts nitric acid speciation toward the nitronium ion.

  2. Promoter analyses and transcriptional profiling of eggplant polyphenol oxidase 1 gene (SmePPO1) reveal differential response to exogenous methyl jasmonate and salicylic acid.

    PubMed

    Shetty, Santoshkumar M; Chandrashekar, Arun; Venkatesh, Yeldur P

    2012-05-01

    The transcriptional regulation of multigenic eggplant (Solanum melongena) polyphenol oxidase genes (SmePPO) is orchestrated by their corresponding promoters which mediate developmentally regulated expression in response to myriad biotic and abiotic factors. However, information on structural features of SmePPO promoters and modulation of their expression by plant defense signals are lacking. In the present study, SmePPOPROMOTERs were cloned by genome walking, and their transcription start sites (TSS) were determined by RLM-RACE. Extensive sequence analyses revealed the presence of evolutionarily conserved and over-represented putative cis-acting elements involved in light-regulated transcription, biosynthetic pathways (phenylpropanoid/flavonoid), hormone signaling (abscisic acid, gibberellic acid, jasmonate and salicylate), elicitor and stress responses (cold/dehydration responses), sugar metabolism and plant defense signaling (W-BOX/WRKY) that are common to SmePPOPROMOTER1 and 2. The TSS for SmePPO genes are located 9-15bp upstream of ATG with variable lengths of 5' untranslated regions. Transcriptional profiling of SmePPOs in eggplant seedlings has indicated differential response to methyl jasmonate (MeJA) or salicylic acid (SA) treatment. In planta, while MeJA elicited expression of all the six SmePPOs, SA was only able to induce the expression of SmePPO4-6. Interestingly, in dual treatment, SA considerably repressed the MeJA-induced expression of SmePPOs. Functional dissection of SmePPOPROMOTER1 by deletion analyses using Agrobacterium-mediated transient expression in tobacco leaves has shown that MeJA enhances the SmePPOPROMOTER1-β-glucuronidase (GUS) expression in vivo, while SA does not. Histochemical and quantitative GUS assays have also indicated the negative effect of SA on MeJA-induced expression of SmePPOPROMOTER1. By combining in silico analyses, transcriptional profiling and expression of SmePPOPROMOTER1-GUS fusions, the role of SA on the modulation

  3. Effect of succinic acid and tween-80 on glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine.

    PubMed

    Baranov, P A; Kravtsova, O U; Sariev, A K; Sherdev, V P

    2008-07-01

    We studied the effect of succinic acid on the process of glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine after peroral and intraperitoneal administration in the form of succinate or a base. Since the basic form of 2-ethyl-6-methyl-3-hydroxypyridine is insoluble in water, it was administered in 5% Tween-80. It was necessary to evaluate also the effect of Tween-80 on glucuronidation of 2-ethyl-6-methyl-3-hydroxypyridine in different administration routes. Quantitative assay of glucuronidated fractions was performed by the method of reversed-phase HPLC with fluorometrical detection. The detection limit for this method was 10 ng/ml. We confirmed that the major excretion pathway for 2-ethyl-6-methyl-3-hydroxypyridine is conjugation with glucuronic acid. It was found that succinic acid increased excretion of glucuronidated metabolite after both peroral and intraperitoneal administration of 2-ethyl-6-methyl-3-hydroxypyridine in the form of succinate and base in 5% Tween-80. The effect of Tween-80 was detected only after peroral administration, which was probably related to its effect on absorption of this compound. Tween-80 increased excretion of glucuronate after peroral administration of 2-ethyl-6-methyl-3-hydroxypyridine in the form of succinate and in 5% Tween solution.

  4. 40 CFR 721.10665 - 2-Propenoic acid, (2-ethyl-2-methyl-1,3-dioxolan-4-yl)methyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10665 2-Propenoic acid, (2-ethyl-2-methyl-1,3-dioxolan-4-yl)methyl ester. (a) Chemical substance and significant new uses subject to reporting. (1)...

  5. Development of an environmentally benign process for the production of fatty acid methyl esters.

    PubMed

    Jordan, V; Gutsche, B

    2001-04-01

    The production of fatty acid methyl esters (FAME) is an important intermediate step in oleochemistry. The oleochemical production route starts with the renewable raw materials fat and oil and ends at fatty alcohols and different special products. Fatty acid methyl esters can be formed at mild reaction temperatures by transesterification of natural triglycerides (fats and oils). This contribution will show the development of a continuous process which is considering the main principles of production integrated environmental protection. The main advantages of this process are low energy consumption and minimal waste production. The process alternatives are shown and a scope on future problems which have to be solved to reach a real additional improvement of the fatty acid methyl esters production is given.

  6. Reversible receptor methylation is essential for normal chemotaxis of Escherichia coli in gradients of aspartic acid.

    PubMed Central

    Weis, R M; Koshland, D E

    1988-01-01

    The chemotaxis of wild-type cells of Escherichia coli and double mutants lacking the methyltransferase and the methylesterase activities of the receptor modification system has been compared in spatial gradients of aspartic acid. Previous studies showing that a chemotactic response can be observed for the mutant raised questions about the role of methylation in the bacterial memory. To clarify the role of methylation, the redistribution of bacteria in stabilized defined gradients of aspartic acid was monitored by light scattering. There was no redistribution of the mutant cells in nonsaturating gradients of aspartic acid, but over the same range these mutant bacteria were observed to respond and to adapt during tethering experiments. In large saturating gradients of aspartate, slight movement of the mutant up the gradient was observed. These results show that dynamic receptor methylation is required for the chemotactic response to gentle gradients of aspartic acid and that methylation resets to zero and is part of the normal wild-type memory. There are certain gradients, however, in which the methylation-deficient mutants show chemotactic ability, thus explaining the apparent anomaly. Images PMID:2829179

  7. Ultrasound in fatty acid chemistry: synthesis of a 1-pyrroline fatty acid ester isomer from methyl ricinoleate.

    PubMed

    Lie Ken Jie, M S; Syed-Rahmatullah, M S; Lam, C K; Kalluri, P

    1994-12-01

    A novel 1-pyrroline fatty acid ester isomer (viz. 8-5-hexyl-1-pyrrolin-2-yl) octanoate) has been synthesized from methyl ricinoleate by two routes with an overall yield of 42 and 30%, respectively. Most of the reactions are carried out under concomitant ultrasonic irradiation (20 KHz, ca. 53 watts/cm2). Under such a reaction condition, the reaction time is considerably shortened, and product yields are high. Dehydrobromination under concomitant ultrasonic irradiation of methyl 9, 10-dibromo-12-hydroxyoctadecanoate with KOH in EtOH furnishes methyl 12-hydroxy-9-octadecynoate (66%) within 15 min. Hydration of the latter under ultrasound with mercury(II)acetate in aqueous tetrahydrofuran yields exclusively methyl 12-hydroxy-9-oxo-octadecanoate (95%) in 30 min. The hydroxy group in the latter compound is transformed to the azido function via the mesylate, and treatment of the azido-oxo intermediate (methyl 12-azido-9-oxooctadecanoate) with Ph3P under ultrasonic irradiation furnishes the requisite 1-pyrroline fatty acid ester (77%). The same azido-oxo intermediate has also been obtained by the oxidation of methyl 12-azido-9-cis-octadecenoate using benzoquinone and a catalytic amount of Pd(II)chloride in aqueous tetrahydrofuran under concomitant ultrasonic irradiation (90 min) to give the product in 45% yield. The latter reaction does not take place even under prolonged silent stirring of the reaction mixture.

  8. Relationships between the resistance of yeasts to acetic, propanoic and benzoic acids and to methyl paraben and pH.

    PubMed

    Warth, A D

    1989-07-01

    Minimum inhibitory concentrations of acetic, propanoic and benzoic acids and methyl paraben were determined at pH 3.50 for 22 isolates of 11 yeast species, differing in their resistance to preservatives. Growth in the presence of benzoic acid enhanced the resistance of yeasts to benzoic and the other weak acid preservatives, but not to methyl paraben. Resistance to acetic, propanoic and benzoic acids was strongly correlated, but was not closely related to resistance to methyl paraben. Minimum pH for growth was not related to resistance to the weak acids. The results suggest that growth in the presence of weak-acid preservatives involves a common resistance mechanism.

  9. Methylation of acidic moieties in poly(methyl methacrylate-co-methacrylic acid) copolymers for end-group characterization by tandem mass spectrometry.

    PubMed

    Giordanengo, Rémi; Viel, Stéphane; Hidalgo, Manuel; Allard-Breton, Béatrice; Thévand, André; Charles, Laurence

    2010-07-30

    The complete structural characterization of a copolymer composed of methacrylic acid (MAA) and methyl methacrylate (MMA) units was achieved using tandem mass spectrometry. In a first step, collision-induced dissociation (CID) of sodiated MAA-MMA co-oligomers allowed us to determine the co-monomeric composition, the random nature of the copolymer and the sum of the end-group masses. However, dissociation reactions of MAA-based molecules mainly involve the acidic pendant groups, precluding individual characterization of the end groups. Therefore, methylation of all the acrylic acid moieties was performed to transform the MAA-MMA copolymer into a PMMA homopolymer, for which CID mainly proceeds via backbone cleavages. Using trimethylsilyldiazomethane as a derivatization agent, this methylation reaction was shown to be complete without affecting the end groups. Using fragmentation rules established for PMMA polymers together with accurate mass measurements of the product ions and knowledge of reagents used for the studied copolymer synthesis, a structure could be proposed for both end groups and it was found to be consistent with signals obtained in nuclear magnetic resonance spectra.

  10. Standardizing methylation method during phospholipid fatty acid analysis to profile soil microbial communities.

    PubMed

    Chowdhury, Taniya Roy; Dick, Richard P

    2012-02-01

    Phospholipid fatty acid (PLFA) as biomarkers, is widely used to profile microbial communities in environmental samples. However, PLFA extraction and derivatization protocols are not standardized and have widely varied among published studies. Specifically investigators have used either HCl/MeOH or KOH/MeOH or both for the methylation step of PLFA analysis, without justification or research to support either one. It seems likely that each method could have very different outcomes and conclusions for PLFA based studies. Therefore, the objective of this study was to determine the effect of catalyst type for methylation on detecting PLFAs and implications for interpreting microbial profiling in soil. Fatty acid samples extracted from soils obtained from a wetland, an intermittently flooded site, and an adjacent upland site were subjected to HCl/MeOH or KOH/MeOH catalyzed methylation procedures during PLFA analyses. The methylation method using HCl/MeOH resulted in significantly higher concentrations of most PLFAs than the KOH/MeOH method. Another important outcome was that fatty acids with a methyl group (18:1ω,7c 11Me, TBSA 10Me 18:0, 10Me 18:0, 17:0 10Me and 16:0 10Me being an actinomycetes biomarker) could not be detected by HCl/MeOH catalyzed methylation but were found in appreciable concentrations with KOH/MeOH method. From our results, because the HCl/MeOH method did not detect the fatty acids containing methyl groups that could strongly influence the microbial community profile, we recommend that the KOH/MeOH catalyzed transesterification method should become the standard procedure for PLFA profiling of soil microbial communities.

  11. Synthesis of (S)-ricinoleic acid and its methyl ester with the participation of ionic liquid.

    PubMed

    Kula, Józef; Bonikowski, Radoslaw; Szewczyk, Malgorzata; Ciolak, Kornelia

    2014-10-01

    (R)-ricinoleic acid methyl ester obtained from commercial castor oil was transformed in a three-step procedure into its S-enantiomer in overall 36% yield using ionic liquid (1-butyl-3-methylimidazolium acetate) in the key step process. The developed procedure provides easy access to (S)-ricinoleic acid and its methyl ester of over 95% enantiomeric excess. Optical rotations of the newly obtained compounds as well as their chromatographic and spectral characteristics are provided and discussed in the context of enantiopurity both of the substrate material and the final products.

  12. Antimicrobial activity of fatty acid methyl esters of some members of Chenopodiaceae.

    PubMed

    Chandrasekaran, Manivachagam; Kannathasan, Krishnan; Venkatesalu, Venugopalan

    2008-01-01

    Fatty acid methyl ester (FAME) extracts of four halophytic plants, viz. Arthrocnemum indicum, Salicornia brachiata, Suaeda maritima and Suaeda monoica belonging to the family Chenopodiaceae, were prepared and their composition was analyzed by GC-MS. The FAME extracts were also screened for antibacterial and antifungal activities. The GC-MS analysis revealed the presence of more saturated fatty acids than unsaturated fatty acids. Among the fatty acids analyzed, the relative percentage of lauric acid was high in S. brachiata (61.85%). The FAME extract of S. brachiata showed the highest antibacterial and antifungal activities among the extracts tested. The other three extracts showed potent antibacterial and moderate anticandidal activities.

  13. Conformational free energies of methyl-α-L-iduronic and methyl-β-D-glucuronic acids in water

    NASA Astrophysics Data System (ADS)

    Babin, Volodymyr; Sagui, Celeste

    2010-03-01

    We present a simulation protocol that allows for efficient sampling of the degrees of freedom of a solute in explicit solvent. The protocol involves using a nonequilibrium umbrella sampling method, in this case, the recently developed adaptively biased molecular dynamics method, to compute an approximate free energy for the slow modes of the solute in explicit solvent. This approximate free energy is then used to set up a Hamiltonian replica exchange scheme that samples both from biased and unbiased distributions. The final accurate free energy is recovered via the weighted histogram analysis technique applied to all the replicas, and equilibrium properties of the solute are computed from the unbiased trajectory. We illustrate the approach by applying it to the study of the puckering landscapes of the methyl glycosides of α-L-iduronic acid and its C5 epimer β-D-glucuronic acid in water. Big savings in computational resources are gained in comparison to the standard parallel tempering method.

  14. Overexpression of salicylic acid carboxyl methyltransferase reduces salicylic acid-mediated pathogen resistance in Arabidopsis thaliana.

    PubMed

    Koo, Yeon Jong; Kim, Myeong Ae; Kim, Eun Hye; Song, Jong Tae; Jung, Choonkyun; Moon, Joon-Kwan; Kim, Jeong-Han; Seo, Hak Soo; Song, Sang Ik; Kim, Ju-Kon; Lee, Jong Seob; Cheong, Jong-Joo; Choi, Yang Do

    2007-05-01

    We cloned a salicylic acid/benzoic acid carboxyl methyltransferase gene, OsBSMT1, from Oryza sativa. A recombinant OsBSMT1 protein obtained by expressing the gene in Escherichia coli exhibited carboxyl methyltransferase activity in reactions with salicylic acid (SA), benzoic acid (BA), and de-S-methyl benzo(1,2,3)thiadiazole-7-carbothioic acid (dSM-BTH), producing methyl salicylate (MeSA), methyl benzoate (MeBA), and methyl dSM-BTH (MeBTH), respectively. Compared to wild-type plants, transgenic Arabidopsis overexpressing OsBSMT1 accumulated considerably higher levels of MeSA and MeBA, some of which were vaporized into the environment. Upon infection with the bacterial pathogen Pseudomonas syringae or the fungal pathogen Golovinomyces orontii, transgenic plants failed to accumulate SA and its glucoside (SAG), becoming more susceptible to disease than wild-type plants. OsBSMT1-overexpressing Arabidopsis showed little induction of PR-1 when treated with SA or G. orontii. Notably, incubation with the transgenic plant was sufficient to trigger PR-1 induction in neighboring wild-type plants. Together, our results indicate that in the absence of SA, MeSA alone cannot induce a defense response, yet it serves as an airborne signal for plant-to-plant communication. We also found that jasmonic acid (JA) induced AtBSMT1, which may contribute to an antagonistic effect on SA signaling pathways by depleting the SA pool in plants.

  15. Design and synthesis of N-benzoyl amino acid derivatives as DNA methylation inhibitors.

    PubMed

    Garella, Davide; Atlante, Sandra; Borretto, Emily; Cocco, Mattia; Giorgis, Marta; Costale, Annalisa; Stevanato, Livio; Miglio, Gianluca; Cencioni, Chiara; Fernández-de Gortari, Eli; Medina-Franco, José L; Spallotta, Francesco; Gaetano, Carlo; Bertinaria, Massimo

    2016-11-01

    The inhibition of human DNA Methyl Transferases (DNMT) is a novel promising approach to address the epigenetic dysregulation of gene expression in different diseases. Inspired by the validated virtual screening hit NSC137546, a series of N-benzoyl amino acid analogues was synthesized and obtained compounds were assessed for their ability to inhibit DNMT-dependent DNA methylation in vitro. The biological screening allowed the definition of a set of preliminary structure-activity relationships and the identification of compounds promising for further development. Among the synthesized compounds, L-glutamic acid derivatives 22, 23, and 24 showed the highest ability to prevent DNA methylation in a total cell lysate. Compound 22 inhibited DNMT1 and DNMT3A activity in a concentration-dependent manner in the micromolar range. In addition, compound 22 proved to be stable in human serum and it was thus selected as a starting point for further biological studies.

  16. An enhanced procedure for measuring organic acids and methyl esters in PM2.5

    NASA Astrophysics Data System (ADS)

    Liu, F.; Duan, F.; He, K.; Ma, Y.; Rahn, K. A.; Zhang, Q.

    2015-03-01

    We have developed an enhanced analytical procedure to measure organic acids and methyl esters in fine aerosol with much greater specificity and sensitivity than previously available. This capability is important because of these species and their low concentrations, even in highly polluted atmospheres like Beijing, China. The procedure first separates the acids and esters from the other organic compounds with anion-exchange solid- phase extraction (SPE), then, quantifies them by gas chromatography coupled with mass spectrometry. This allows us to accurately quantify the C4-C11 dicarboxylic and the C8-C30 monocarboxylic acids. Then the acids are separated from the esters on an aminopropyl SPE cartridge, whose weak retention isolates and enriches the acids from esters prevents the fatty acids and dimethyl phthalate from being overestimated. The resulting correlations between the aliphatic acids and fatty acid methyl esters (FAMEs) suggest that FAMEs had sources similar to those of the carboxylic acids, or were formed by esterifying carboxylic acids, or that aliphatic acids were formed by hydrolyzing FAMEs. In all, 17 aromatic acids were identified and quantified using this procedure coupled with gas chromatography-tandem mass spectrometry, including the five polycyclic aromatic hydrocarbon (PAH) acids 2-naphthoic, biphenyl-4-carboxylic, 9-oxo-9H-fluorene-1-carboxylic, biphenyl-4,4´-dicarboxylic, and phenanthrene-1-carboxylic acid, plus 1,8-naphthalic anhydride. Correlations between the PAH-acids and the dicarboxylic and aromatic acids indicated that the first three acids and 1,8-naphthalic anhydride were mainly secondary, the last two mainly primary.

  17. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction...

  18. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction...

  19. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction...

  20. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction...

  1. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction...

  2. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... from edible fats and oils. 172.225 Section 172.225 Food and Drugs FOOD AND DRUG ADMINISTRATION... Methyl and ethyl esters of fatty acids produced from edible fats and oils. Methyl esters and ethyl esters of fatty acids produced from edible fats and oils may be safely used in food, subject to...

  3. Endogenous Methyl Salicylate in Pathogen-Inoculated Tobacco Plants1

    PubMed Central

    Seskar, Mirjana; Shulaev, Vladimir; Raskin, Ilya

    1998-01-01

    The tobacco (Nicotiana tabacum) cultivar Xanthi-nc (genotype NN) produces high levels of salicylic acid (SA) after inoculation with the tobacco mosaic virus (TMV). Gaseous methyl salicylate (MeSA), a major volatile produced in TMV-inoculated tobacco plants, was recently shown to be an airborne defense signal. Using an assay developed to measure the MeSA present in tissue, we have shown that in TMV-inoculated tobacco plants the level of MeSA increases dramatically, paralleling increases in SA. MeSA accumulation was also observed in upper, noninoculated leaves. In TMV-inoculated tobacco shifted from 32 to 24°C, the MeSA concentration increased from nondetectable levels to 2318 ng/g fresh weight 12 h after the temperature shift, but subsequently decreased with the onset of the hypersensitive response. Similar results were observed in plants inoculated with Pseudomonas syringae pathovar phaseolicola, in which MeSA levels were highest just before the hypersensitive response-induced tissue desiccation. Transgenic NahG plants unable to accumulate SA also did not accumulate MeSA after TMV inoculation, and did not show increased resistance to TMV following MeSA treatment. Based on the spatial and temporal kinetics of its accumulation, we conclude that tissue MeSA may play a role similar to that of volatile MeSA in the pathogen-induced defense response.

  4. 21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Methyl esters of conjugated linoleic acid (cis-9... § 573.637 Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic acids). The food additive, methyl esters of conjugated linoleic acid (cis-9, trans-11 and...

  5. Cold flow properties of fatty acid methyl esters: Additives versus diluents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel is typically composed of fatty acid methyl esters (FAME) converted from agricultural lipids. Common feedstocks include soybean oil, canola oil, rapeseed oil, sunflower oil, and palm oil. Recent debate on the conversion of edible oils into non-food products has created opportunities to deve...

  6. Catalytic synthesis of fatty acid methyl esters from extremely low quality greases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel (BD) is a renewable fuel for compression ignition engines that is composed of the simple alkyl esters, usually methyl-, of fatty acids (FAME). It is typically produced via base-catalyzed transesterification between refined vegetable oil or animal fat (e.g., soybean oil, tallow) and an alc...

  7. Prediction of preweaning ADG in beef calves from milk fatty acid methyl esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research has shown milk yield (MWT) has an important influence on calf preweaning ADG (PRWADG), but MWT accounts for only a moderate amount of variation in PRWADG. The objective of this study was to determine if milk fatty acid methyl esters (FAME), alone and in combination with MWT, could improve a...

  8. Chemically Modified Fatty Acid Methyl Esters: Potential as Lubricant and Surfactant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Renewable raw materials are going to play a noteworthy role in the development of sustainable green chemistry because of their eco-friendly and non-toxic nature. A novel process was developed for the production of biodegradable lubricant base stocks from epoxidized fatty acid methyl esters and comm...

  9. PLASMID DNA DAMAGE CAUSED BY METHYLATED ARSENICALS, ASCORBIC ACID AND HUMAN LIVER FERRITIN

    EPA Science Inventory

    Plasmid DNA damage caused by methylated arsenicals, ascorbic acid and human liver ferritin.

    Arsenic causes cancer in human skin, urinary bladder, lung, liver and kidney and is a significant world-wide public health problem. Although the metabolism of inorganic arsenic is ...

  10. Esterification and Transesterification of greases to fatty acid methyl esters with highly active diphenylamine salts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diphenylamine sulfate (DPAS) and diphenylamine hydrochloride (DPACl) salts were found to be highly active catalysts for esterification and transesterification of inexpensive greases to fatty acid methyl esters (FAME). In the presence of catalytic amounts of DPAS or DPACl and excess methanol, the fr...

  11. Esterification and transesterification of greases to fatty acid methyl esters with highly active diphanylammonium salts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have conducted an investigation designed to identify alternate catalysts for the production of fatty acid methyl esters (FAME) to be used as biodiesel. Diphenylammonium sulfate (DPAS) and diphenylammonium chloride (DPA-HCl) salts were found to be highly active homogeneous catalysts for the simu...

  12. Separation and quantitation of free fatty acids and fatty acid methyl esters by reverse phase high pressure liquid chromatography.

    PubMed

    Aveldano, M I; VanRollins, M; Horrocks, L A

    1983-01-01

    Reverse phase high pressure liquid chromatography (HPLC) on octadecylsilyl columns separates mixtures of either free fatty acids or fatty acid methyl esters prepared from mammalian tissue phospholipids. Acetonitrile-water mixtures are used for the elution of esters. Aqueous phosphoric acid is substituted for water for the separation of the free acids. Unsaturated compounds are detected and quantitated by their absorption at 192 nm. Saturates are detected better at 205 nm. The order of elution of fatty acids in complex mixtures varies as a function of acetonitrile concentration. At any given concentration, some compounds overlap. However, by varying the solvent strength, any fatty acid of interest can be resolved including many geometrical and positional isomers. Methyl esters prefractionated according to unsaturation by argentation thin-layer chromatography (TLC) are rapidly and completely separated by elution with CH3CN alone. Argentation TLC-reverse phase HPLC can be used as an analytical as well as a preparative procedure. Octylsilyl columns are used for rapid resolution and improved detection of minor or low ultraviolet-absorbing components in the fractions. For example, monoenoic fatty acids with up to 32 carbons have been detected in bovine brain glycerophospholipids. Specific radioactivities of 3H- and 14C-labeled fatty acids and the distribution of radioactivity among acyl groups from complex lipids are measured. The method is not recommended for complete compositional analysis, but is useful for determinations of specific radioactivities during studies on turnover and metabolic conversions of labeled fatty acids.

  13. An enhanced procedure for measuring organic acids and methyl esters in PM2.5

    NASA Astrophysics Data System (ADS)

    Liu, F.; Duan, F. K.; He, K. B.; Ma, Y. L.; Rahn, K. A.; Zhang, Q.

    2015-11-01

    A solid-phase extraction (SPE) pretreatment procedure allowing organic acids to be separated from methyl esters in fine aerosol has been developed. The procedure first separates the organic acids from fatty acid methyl esters (FAMEs) and other nonacid organic compounds by aminopropyl-based SPE cartridge and then quantifies them by gas chromatography/mass spectrometry. The procedure prevents the fatty acids and dimethyl phthalate from being overestimated, and so allows us to accurately quantify the C4-C11 dicarboxylic acids (DCAs) and the C8-C30 monocarboxylic acids (MCAs). Results for the extraction of DCAs, MCAs, and AMAs in eluate and FAMEs in effluate by SAX and NH2 SPE cartridges exhibited that the NH2 SPE cartridge gave higher extraction efficiency than the SAX cartridge. The recoveries of analytes ranged from 67.5 to 111.3 %, and the RSD ranged from 0.7 to 10.9 %. The resulting correlations between the aliphatic acids and FAMEs suggest that the FAMEs had sources similar to those of the carboxylic acids, or were formed by esterifying carboxylic acids, or that aliphatic acids were formed by hydrolyzing FAMEs. Through extraction and cleanup using this procedure, 17 aromatic acids in eluate were identified and quantified by gas chromatography/tandem mass spectrometry, including five polycyclic aromatic hydrocarbon (PAH): acids 2-naphthoic, biphenyl-4-carboxylic, 9-oxo-9H-fluorene-1-carboxylic, biphenyl-4,4´-dicarboxylic, and phenanthrene-1-carboxylic acid, plus 1,8-naphthalic anhydride. Correlations between the PAH acids and the dicarboxylic and aromatic acids suggested that the first three acids and 1,8-naphthalic anhydride were secondary atmospheric photochemistry products and the last two mainly primary.

  14. Transferable force field for carboxylate esters: application to fatty acid methylic ester phase equilibria prediction.

    PubMed

    Ferrando, Nicolas; Lachet, Véronique; Boutin, Anne

    2012-03-15

    In this work, a new transferable united-atoms force field for carboxylate esters is proposed. All Lennard-Jones parameters are reused from previous parametrizations of the AUA4 force field, and only a unique set of partial electrostatic charges is introduced for the ester chemical function. Various short alkyl-chain esters (methyl acetate, ethyl acetate, methyl propionate, ethyl propionate) and two fatty acid methylic esters (methyl oleate and methyl palmitate) are studied. Using this new force field in Monte Carlo simulations, we show that various pure compound properties are accurately predicted: saturated liquid densities, vapor pressures, vaporization enthalpies, critical properties, liquid-vapor surface tensions. Furthermore, a good accuracy is also obtained in the prediction of binary mixture pressure-composition diagrams, without introducing empirical binary interaction parameters. This highlights the transferability of the proposed force field and gives the opportunity to simulate mixtures of industrial interest: a demonstration is performed through the simulation of the methyl oleate + methanol mixture involved in the purification sections of biodiesel production processes.

  15. DNA Methylation of Cellular Retinoic Acid-Binding Proteins in Cervical Cancer.

    PubMed

    Arellano-Ortiz, Ana L; Salcedo-Vargas, Mauricio; Vargas-Requena, Claudia L; López-Díaz, José A; De la Mora-Covarrubias, Antonio; Silva-Espinoza, Juan C; Jiménez-Vega, Florinda

    2016-01-01

    This study determined the methylation status of cellular retinoic acid-binding protein (CRABP) gene promoters and associated them with demographic characteristics, habits, and the presence of human papilloma virus (HPV) in patients with cervical cancer (CC), low and high squamous intraepithelial lesions, and no intraepithelial lesion. Women (n = 158) were selected from the Colposcopy Clinic of Sanitary Jurisdiction II in Ciudad Juarez, Chihuahua, Mexico. Demographic characteristics and habit information were collected. Cervical biopsy and endocervical scraping were used to determine methylation in promoter regions by methylation-specific polymerase chain reaction technique. We found hemi-methylation patterns in the promoter regions of CRABP1 and CRABP2; there was 28.5% hemi-methylation in CRABP1 and 7.0% in that of CRABP2. Methylation in CRABP1 was associated with age (≥35 years, P = 0.002), family history of cancer (P = 0.032), the presence of HPV-16 (P = 0.013), and no alcohol intake (P = 0.035). These epigenetic changes could be involved in the CC process, and CRABP1 has the potential to be a predictive molecular marker of retinoid therapy response.

  16. DNA Methylation of Cellular Retinoic Acid-Binding Proteins in Cervical Cancer

    PubMed Central

    Arellano-Ortiz, Ana L.; Salcedo-Vargas, Mauricio; Vargas-Requena, Claudia L.; López-Díaz, José A.; De la Mora-Covarrubias, Antonio; Silva-Espinoza, Juan C.; Jiménez-Vega, Florinda

    2016-01-01

    This study determined the methylation status of cellular retinoic acid-binding protein (CRABP) gene promoters and associated them with demographic characteristics, habits, and the presence of human papilloma virus (HPV) in patients with cervical cancer (CC), low and high squamous intraepithelial lesions, and no intraepithelial lesion. Women (n = 158) were selected from the Colposcopy Clinic of Sanitary Jurisdiction II in Ciudad Juarez, Chihuahua, Mexico. Demographic characteristics and habit information were collected. Cervical biopsy and endocervical scraping were used to determine methylation in promoter regions by methylation-specific polymerase chain reaction technique. We found hemi-methylation patterns in the promoter regions of CRABP1 and CRABP2; there was 28.5% hemi-methylation in CRABP1 and 7.0% in that of CRABP2. Methylation in CRABP1 was associated with age (≥35 years, P = 0.002), family history of cancer (P = 0.032), the presence of HPV-16 (P = 0.013), and no alcohol intake (P = 0.035). These epigenetic changes could be involved in the CC process, and CRABP1 has the potential to be a predictive molecular marker of retinoid therapy response. PMID:27867303

  17. Experimental and Computational Study on the Molecular Energetics of 2-Pyrrolecarboxylic Acid and 1-Methyl-2-pyrrolecarboxylic Acid

    NASA Astrophysics Data System (ADS)

    Santos, Ana Filipa L. O. M.; Silva, Manuel A. V. Ribeiro Da

    2009-08-01

    This paper reports a combined thermochemical experimental and computational study of 2-pyrrolecarboxylic acid and 1-methyl-2-pyrrolecarboxylic acid. Static bomb combustion calorimetry and Knudsen mass-loss effusion technique were used to determine the standard (p° = 0.1 MPa) molar enthalpies of combustion, ΔcHm°, and sublimation, ΔcrgHm°, respectively, from which the standard (p° = 0.1 MPa) molar enthalpies of formation, in the gaseous phase, at T = 298.15 K, were derived. The values obtained were -(286.3 ± 1.7) and -(291.6 ± 1.7) kJ·mol for 2-pyrrolecarboxylic acid and 1-methyl-2-pyrrolecarboxylic acid, respectively. For comparison purposes, the gas-phase enthalpies of formation of these two compounds were estimated by G3(MP2)//B3LYP and MP2 approaches, using a set of gas-phase working reactions; the results are in excellent agreement with experimental data. G3(MP2)//B3LYP computations were also extended to the calculation of N-H bond dissociation enthalpies, gas-phase acidities and basicities, proton and electron affinities and adiabatic ionization enthalpies. Moreover, the results are also discussed in terms of the energetic effects of the addition of a carboxylic and of a methyl groups to the pyrrole ring and compared with structurally similar compounds.

  18. Biosynthesis and emission of insect-induced methyl salicylate and methyl benzoate from rice

    SciTech Connect

    Zhao, Nan; Guan, Ju; Ferrer, Jean-Luc; Engle, Nancy L; Chern, Mawsheng; Ronald, Pamela; Tschaplinski, Timothy J; Chen, Feng

    2010-01-01

    Two benzenoid esters, methyl salicylate (MeSA) and methyl benzoate (MeBA), were detected from insect-damaged rice plants. By correlating metabolite production with gene expression analysis, five candidate genes encoding putative carboxyl methyltransferases were identified. Enzymatic assays with Escherichia coli-expressed recombinant proteins demonstrated that only one of the five candidates, OsBSMT1, has salicylic acid (SA) methyltransferase (SAMT) and benzoic acid (BA) methyltransferase (BAMT) activities for producing MeSA and MeBA, respectively. Whereas OsBSMT1 is phylogenetically relatively distant from dicot SAMTs, the three-dimensional structure of OsBSMT1, which was determined using homology-based structural modeling, is highly similar to those of characterized SAMTs. Analyses of OsBSMT1 expression in wild-type rice plants under various stress conditions indicate that the jasmonic acid (JA) signaling pathway plays a critical role in regulating the production and emission of MeSA in rice. Further analysis using transgenic rice plants overexpressing NH1, a key component of the SA signaling pathway in rice, suggests that the SA signaling pathway also plays an important role in governing OsBSMT1 expression and emission of its products, probably through a crosstalk with the JA signaling pathway. The role of the volatile products of OsBSMT1, MeSA and MeBA, in rice defense against insect herbivory is discussed.

  19. Tailoring acidity of HZSM-5 nanoparticles for methyl bromide dehydrobromination by Al and Mg incorporation

    PubMed Central

    2014-01-01

    Three kinds of HZSM-5 nanoparticles with different acidity were tailored by impregnating MgO or varying Si/Al ratios. Both the textural and acidic properties of the as-prepared nanoparticles were characterized by nitrogen adsorption-desorption measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), ammonia temperature-programmed desorption (NH3-TPD) and Fourier transform infrared spectroscopy (FTIR or Py-FTIR). It was found that the intensity of Lewis acid sites with weak strength was enhanced by impregnating MgO or reducing Al concentration, and such an enhancement could be explained by the formation of Mg(OH)+ or charge unbalance of the MgO framework on the surface of HZSM-5 support. The effect of HZSM-5 nanoparticles' acidity on methyl bromide dehydrobromination as catalyst was evaluated. As the results, MgHZ-360 catalyst with the highest concentration of Lewis acid sites showed excellent stability, which maintained methyl bromide conversion of up 97% in a period of 400 h on stream. Coke characterization by BET measurements and TGA/DTA and GC/MS analysis revealed that polymethylated naphthalenes species were formed outside the channels of the catalyst with higher acid intensity and higher Brønsted acid concentration during the initial period of reaction, while graphitic carbon formed in the channels of catalyst with lower acid intensity and higher Lewis acid concentration during the stable stage. PMID:25328502

  20. Thermochemistry of C-O, (CO)-O, and (CO)-C bond breaking in fatty acid methyl esters

    SciTech Connect

    Osmont, Antoine; Yahyaoui, Mohammed; Catoire, Laurent; Goekalp, Iskender; Swihart, Mark T.

    2008-10-15

    Density functional theory quantum chemical calculations corrected with empirical atomic increments have been used to examine C-O, (CO)-O, and (CO)-C bond scission enthalpies in gas-phase fatty acid methyl esters (FAMEs) present in biodiesel derived from rapeseed oil methyl ester and soybean oil methyl ester. Mechanistic information, currently not available elsewhere for these large species, is obtained based on thermochemical considerations and compared to thermochemical considerations reported for methyl butanoate, a small methyl ester sometimes used as a model for FAMEs. These results are compared to previously reported C-C and C-H bond scissions in these FAMEs, derived using this same protocol. (author)

  1. Efficient production of the Nylon 12 monomer ω-aminododecanoic acid methyl ester from renewable dodecanoic acid methyl ester with engineered Escherichia coli.

    PubMed

    Ladkau, Nadine; Assmann, Miriam; Schrewe, Manfred; Julsing, Mattijs K; Schmid, Andreas; Bühler, Bruno

    2016-07-01

    The expansion of microbial substrate and product scopes will be an important brick promoting future bioeconomy. In this study, an orthogonal pathway running in parallel to native metabolism and converting renewable dodecanoic acid methyl ester (DAME) via terminal alcohol and aldehyde to 12-aminododecanoic acid methyl ester (ADAME), a building block for the high-performance polymer Nylon 12, was engineered in Escherichia coli and optimized regarding substrate uptake, substrate requirements, host strain choice, flux, and product yield. Efficient DAME uptake was achieved by means of the hydrophobic outer membrane porin AlkL increasing maximum oxygenation and transamination activities 8.3 and 7.6-fold, respectively. An optimized coupling to the pyruvate node via a heterologous alanine dehydrogenase enabled efficient intracellular L-alanine supply, a prerequisite for self-sufficient whole-cell transaminase catalysis. Finally, the introduction of a respiratory chain-linked alcohol dehydrogenase enabled an increase in pathway flux, the minimization of undesired overoxidation to the respective carboxylic acid, and thus the efficient formation of ADAME as main product. The completely synthetic orthogonal pathway presented in this study sets the stage for Nylon 12 production from renewables. Its effective operation achieved via fine tuning the connectivity to native cell functionalities emphasizes the potential of this concept to expand microbial substrate and product scopes.

  2. Gas chromatography-vacuum ultraviolet spectroscopy for analysis of fatty acid methyl esters.

    PubMed

    Fan, Hui; Smuts, Jonathan; Bai, Ling; Walsh, Phillip; Armstrong, Daniel W; Schug, Kevin A

    2016-03-01

    A new vacuum ultraviolet (VUV) detector for gas chromatography was recently developed and applied to fatty acid methyl ester (FAME) analysis. VUV detection features full spectral acquisition in a wavelength range of 115-240nm, where virtually all chemical species absorb. VUV absorption spectra of 37 FAMEs, including saturated, monounsaturated, and polyunsaturated types were recorded. Unsaturated FAMEs show significantly different gas phase absorption profiles than saturated ones, and these classes can be easily distinguished with the VUV detector. Another advantage includes differentiating cis/trans-isomeric FAMEs (e.g. oleic acid methyl ester and linoleic acid methyl ester isomers) and the ability to use VUV data analysis software for deconvolution of co-eluting signals. As a universal detector, VUV also provides high specificity, sensitivity, and a fast data acquisition rate, making it a powerful tool for fatty acid screening when combined with gas chromatography. The fatty acid profile of several food oil samples (olive, canola, vegetable, corn, sunflower and peanut oils) were analyzed in this study to demonstrate applicability to real world samples.

  3. Surfactant-modified fatty acid composition of Citrobacter sp. SA01 and its effect on phenanthrene transmembrane transport.

    PubMed

    Li, Feng; Zhu, Lizhong

    2014-07-01

    The effects of the surfactants, Tween 80 and sodium dodecyl benzene sulfonate (SDBS) on a membrane's fatty acid composition and the transmembrane transport of phenanthrene were investigated. The results indicated that both surfactants could modify the composition of fatty acids of Citrobacter sp. Strain SA01 cells, 50 mg L(-1) of both surfactants changed the composition of the fatty acids the most, increasing the amount of unsaturated fatty acids. The comparison of fatty acid profiles with diphenylhexatriene fluorescence anisotropy, a probe for plasma membrane fluidity, suggested that an increased amount of unsaturated fatty acids corresponded to greater membrane fluidity. In addition, increased unsaturated fatty acids promoted phenanthrene to partition from the extracellular matrix to cell debris, which increased reverse partitioning from the cell debris to the cytochylema. The results of this study were expected in that the addition of a surfactant is a simple and effective method for accelerating the rate-limiting step of transmembrane transport of hydrophobic organic compounds (HOCs) in bioremediation.

  4. Comparative study of the fatty acid composition of sponges of the genus Ircinia. Identification of the new 23-methyl-5,9-tetracosadienoic acid.

    PubMed

    Carballeira, N M; Shalabi, F; Cruz, C; Rodriguez, J; Rodriguez, E

    1991-01-01

    1. The phospholipid fatty acid compositions of the sponges Ircinia strobilina, Ircinia felix, Ircinia campana, Ircinia sp., Spongia tubulifera and Dysidea etherea were studied, revealing the presence, besides other common fatty acids, of considerable amounts (2-5%) of the novel 23-methyl-5,9-tetracosadienoic acid (1). 2. The demospongic acids 5,9-tetracosadienoic acid, 23-methyl-5,9-tetracosadienoic acid (1), and 5,9-pentacosadienoic acid, were particularly abundant in sponges of the genus Ircinia, in contrast to the most common 5,9-hexacosadienoic acid found in other species. These findings are discussed in terms of the taxonomy of the Dictyoceratida. 3. The complete characterization of the novel phospholipid fatty acid 23-methyl-5,9-tetracosadienoic acid (1) is presented.

  5. Acetylsalicylic acid, aging and coronary artery disease are associated with ABCA1 DNA methylation in men

    PubMed Central

    2014-01-01

    Background Previous studies have suggested that DNA methylation contributes to coronary artery disease (CAD) risk variability. DNA hypermethylation at the ATP-binding cassette transporter A1 (ABCA1) gene, an important modulator of high-density lipoprotein cholesterol and reverse cholesterol transport, has been previously associated with plasma lipid levels, aging and CAD, but the association with CAD has yet to be replicated. Results ABCA1 DNA methylation levels were measured in leucocytes of 88 men using bis-pyrosequencing. We first showed that DNA methylation at the ABCA1 gene promoter locus is associated with aging and CAD occurrence in men (P < 0.05). The latter association is stronger among older men with CAD (≥61 years old; n = 19), who showed at least 4.7% higher ABCA1 DNA methylation levels as compared to younger men with CAD (<61 years old; n = 19) or men without CAD (n = 50; P < 0.001). Higher ABCA1 DNA methylation levels in older men were also associated with higher total cholesterol (r = 0.34, P = 0.03), low-density lipoprotein cholesterol (r = 0.32, P = 0.04) and triglyceride levels (r = 0.26, P = 0.09). Furthermore, we showed that acetylsalicylic acid therapy is associated with 3.6% lower ABCA1 DNA methylation levels (P = 0.006), independent of aging and CAD status of patients. Conclusions This study provides new evidence that the ABCA1 epigenetic profile is associated with CAD and aging, and highlights that epigenetic modifications might be a significant molecular mechanism involved in the pathophysiological processes associated with CAD. Acetylsalicylic acid treatment for CAD prevention might involve epigenetic mechanisms. PMID:25093045

  6. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Significant New Uses for Specific Chemical Substances § 721.1725 Benzoic acid, 3,3′-methyl-enebis [6 amino..., Benzoic acid, 3,3′-methylenebis [6 amino-, di-2-propenyl ester. (2) The significant new uses are: (i) Any... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzoic acid, 3,3â²-methyl-enebis...

  7. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Significant New Uses for Specific Chemical Substances § 721.1725 Benzoic acid, 3,3′-methyl-enebis [6 amino..., Benzoic acid, 3,3′-methylenebis [6 amino-, di-2-propenyl ester. (2) The significant new uses are: (i) Any... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzoic acid, 3,3â²-methyl-enebis...

  8. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Significant New Uses for Specific Chemical Substances § 721.1725 Benzoic acid, 3,3′-methyl-enebis [6 amino..., Benzoic acid, 3,3′-methylenebis [6 amino-, di-2-propenyl ester. (2) The significant new uses are: (i) Any... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzoic acid, 3,3â²-methyl-enebis...

  9. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Significant New Uses for Specific Chemical Substances § 721.1725 Benzoic acid, 3,3′-methyl-enebis [6 amino..., Benzoic acid, 3,3′-methylenebis [6 amino-, di-2-propenyl ester. (2) The significant new uses are: (i) Any... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzoic acid, 3,3â²-methyl-enebis...

  10. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Significant New Uses for Specific Chemical Substances § 721.1725 Benzoic acid, 3,3′-methyl-enebis [6 amino..., Benzoic acid, 3,3′-methylenebis [6 amino-, di-2-propenyl ester. (2) The significant new uses are: (i) Any... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzoic acid, 3,3â²-methyl-enebis...

  11. Accumulation of methyl-deficient rat liver messenger ribonucleic acid on ethionine administration

    SciTech Connect

    Goswami, B.B.; Sharma, O.K.

    1980-01-01

    Highly purified poly(adenylic acid)-containing RNA isolated from livers of rats fed 0.25% DL-etionine in the diet for 7 days accepted methyl groups from S-adenosyl(methyl-/sup 3/H)methionine, when incubated in vitro with mRNA methyltransferases from vaccinia virus or Ehrlich ascites cells, whereas RNA from control rats had no such activity. Nuclease digestion followed by chromatographic analyses of mRNA methylated in vitro revealed that the methyl groups were incorporated at the 5' end into cap 1 structures (m/sup 7/GpppNmp...) by the viral enzyme, whereas both cap 0 (m/sup 7/GpppNp...) and cap 1 (m/sup 7/Gpppm/sup 6/Am...) structures were formed by the Ehrlich ascites cell enzymes. the methyl-deficient mRNA isolated from the liver of ethionine-fed rats differed in its translational properties from mRNA isolated from control animals in an in vitro protein synthesizing system from wheat germ.

  12. Dissociative electron-ion recombination of the interstellar species protonated glycolaldehyde, acetic acid, and methyl formate.

    PubMed

    Lawson, Patrick A; Osborne, David S; Adams, Nigel G

    2012-03-22

    Recently, methyl formate, glycolaldehyde, and acetic acid have been detected in the Interstellar Medium, ISM. The rate constants, α(e), for dissociative electron-ion recombination of protonated gycolaldehyde, (HOCH(2)CHO)H(+), and protonated methyl formate, (HCOOCH(3))H(+), have been determined at 300 K in a variable temperature flowing afterglow using a Langmuir probe to obtain the electron density. The recombination rate constants at 300 K are 3.2 × 10(-7) cm(3) s(-1) for protonated methyl formate and 7.5 × 10(-7) cm(3) s(-1) for protonated glycolaldehyde. The recombination rate constant of protonated acetic acid could not be directly measured, but it appears to have a rate constant, α(e), on the 10(-7) cm(3) s(-1) scale. Several high- and low-temperature measurements for protonated methyl formate were made. In addition, an α(e) measurement at 220 K for protonated glycolaldehyde was performed. The astrochemical implications of the rates of recombination, α(e), and protonation routes are discussed.

  13. Theoretical study of the regioselectivity of the interaction of 3-methyl-4-pyrimidone and 1-methyl-2-pyrimidone with Lewis acids.

    PubMed

    Kasende, Okuma Emile; Muya, Jules Tshishimbi; Broeckaert, Lies; Maes, Guido; Geerlings, Paul

    2012-08-23

    A density functional theory (DFT) study is performed to determine the stability of the complexes formed between either the N or O site of 3-methyl-4-pyrimidone and 1-methyl-2-pyrimidone molecules and different ligands. The studied ligands are boron and alkali Lewis acids, namely, B(CH(3))(3), HB(CH(3))(2), H(2)B(CH(3)), BH(3), H(2)BF, HBF(2), BF(3), Li(+), Na(+), and K(+). The acids are divided into two groups according to their hardness. The reactivity predictions, according to the molecular electrostatic potential (MEP) map and the natural bond orbital (NBO) analysis, are in agreement with the calculated relative stabilities. Our findings reveal a strong regioselectivity with borane and its derivatives preferring the nitrogen site in both pyrimidone isomers, while a preference for oxygen is observed for the alkali acids in the 3-methyl-4-pyrimidone molecule. The complexation of 1-methyl-2-pyrimidone with these hard alkali acids does not show any discrimination between the two sites due to the presence of a continuous delocalized density region between the nitrogen and the oxygen atoms. The preference of boron Lewis acids toward the N site is due to the stronger B-N bond as compared to the B-O bond. The influence of fluorine or methyl substitution on the boron atom is discussed through natural orbital analysis (NBO) concentrating on the overlap of the boron empty p-orbital with the F lone pairs and methyl hyperconjugation, respectively. The electrophilicity of the boron acids gives a good overall picture of the interaction capabilities with the Lewis base.

  14. Methylation of ethylene over Lewis-acid catalysts

    SciTech Connect

    Sekhar, M.V.C.

    1994-12-31

    As a major constituent of natural gas, methane is abundant and is a relatively inexpensive feedstock for a variety of chemicals. The use of methane as a fuel is straightforward. Consequently, over the years, considerable research has been conducted to develop technologies for its efficient utilization. Work on adsorbents for storing natural gas on-board automotive vehicles promises to expand its use considerably. Conversely, the use of methane as a chemical feedstock requires either the energy- and capital-intensive production of intermediate synthesis gas or its thermal cracking to a range of hydrocarbons. In recent years there has been a great deal of interest in processes that convert methane directly to olefins, methanol and other functionalized methane derivatives. Among the various conversion processes currently under development, the Oxidative Coupling (OC) route is the most promising. With increased attention being given to OC process, engineers have also begun outlining the corresponding reaction engineering aspects. The OC of methane rich natural gas yields a dilute olefin stream. At 25% hydrocarbon conversion, the ethylene in the dry reactor effluent is about 5%, with some propylene and other hydrocarbons. Because of the presence of large amounts of unconverted methane in the effluent, product separation is one of the main points of optimization in the existing oxidative coupling technology. Consequently, a processing scheme which does not require further separation of the product of the OC rector would be of considerable advantage. Reactions between methane and ethylene using a number of solid acids have also been reported by a number of authors in the past. However, some of these experiments were conducted at temperatures higher than ambient. In this paper we report some of the results obtained at ambient temperature as part of a screening program for developing catalyst systems for co-reacting methane with ethylene to produce higher hydrocarbons.

  15. [Determination of 2-methyl-3-nitrobenzoic acid through pretreatment with diazomethane by gas chromatography].

    PubMed

    Xue, Ke-She; Nan, Zhi-Xiang

    2002-09-01

    A method for the quantitative determination of 2-methyl-3-nitrobenzoic acid by gas chromatography is described. 2-Methyl-3-nitrobenzoic acid was esterified by pretreatment with diazomethane prior to analysis. A CP-Sil-43CB capillary column(25 m x 0.32 mm i.d. x 0.2 microm), a flame ionization detector and the area normalization method were used. The average recovery was 99.81%. The RSD was 0.08% and the detection limit was 3 x 10(-11) g. The results showed that the method is practical and reliable. It was realized that the higher purity and higher boiler matter was analyzed by gas chromatography. The method can be used to monitor the purity of this type of materials. analysis of research and production. It can be used in the development of new products and in the process.

  16. 21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... produce fatty acid methyl esters, which then undergo conjugation to yield methyl esters of octadecadienoic... contain not less than 35 percent of other fatty acid esters composed of oleic acid, palmitic acid, stearic... the feed of growing and finishing swine as a source of fatty acids at levels not to exceed 0.6% in...

  17. 21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... produce fatty acid methyl esters, which then undergo conjugation to yield methyl esters of octadecadienoic... contain not less than 35 percent of other fatty acid esters composed of oleic acid, palmitic acid, stearic... the feed of growing and finishing swine as a source of fatty acids at levels not to exceed 0.6% in...

  18. Molecularly imprinted films of acrylonitrile/methyl methacrylate/acrylic acid terpolymers: influence of methyl methacrylate in the binding performance of L-ephedrine imprinted films.

    PubMed

    Brisbane, Carrie; McCluskey, Adam; Bowyer, Michael; Holdsworth, Clovia I

    2013-05-07

    Molecularly imprinted polymeric films (MIPFs) highly selective to 1R,2S(-)ephedrine (L-ephedrine, EPD) were produced by phase inversion post-polymerization imprinting on poly(acrylonitrile-co-methyl methacrylate-co-acrylic acid) (PAMA) terpolymers. The inclusion of methyl methacrylate (MMA) to the polymer formulation resulted in enhanced EPD selectivity which appears to be dictated by polymer composition to achieve the necessary balance between polymer rigidity and porosity. Substitution of MMA with methyl acrylate, ethyl acrylate and n-butyl acrylate resulted in a loss of EPD selectivity and EPD entrapment within the polymer matrix not observed in PAMA MIPFs. MMA, by virtue of its methyl group, is able to provide the scaffolding and rigidity necessary for stability and preservation of imprinted cavities within the PAMA MIPF leading to high EPD selectivity.

  19. Observation of the side chain O-methylation of glutamic acid or aspartic acid containing model peptides by electrospray ionization-mass spectrometry.

    PubMed

    Atik, A Emin; Guray, Melda Z; Yalcin, Talat

    2017-03-15

    O-methylation of the side chains of glutamic acid (E) and aspartic acid (D) residues is generally observed modification when an acidified methanol/water (MeOH/dH2O) mixture is used as a solvent system during sample preparation for proteomic research. This chemical modification may result misidentification with endogenous protein methylation; therefore, a special care should be taken during sample handling prior to mass spectrometric analysis. In the current study, we systematically examined the extent of E/D methylation and C-terminus carboxyl group of synthetic model peptides in terms of different incubation temperatures, storage times, and added acid types as well as its percentages. To monitor these effects, C-terminus amidated and free acid forms of synthetic model peptides comprised of E or D residue(s) have been analyzed by electrospray ionization-mass spectrometry (ESI-MS). Additionally, LC-MS/MS experiments were performed to confirm the formation of methylated peptide product. The results showed that the rate of methylation was increased as the temperature increases along with prolong incubation times. Moreover, the extent of methylation was remarkably high when formic acid (FA) used as a protonation agent instead of acetic acid (AA). In addition, it was found that the degree of methylation was significantly decreased by lowering acid percentages in ESI solution. More than one acidic residue containing model peptides have been also used to explore the extent of multiple methylation reaction. Lastly, the ethanol (EtOH) and isopropanol (iPrOH) have been substituted separately with MeOH in sample preparation step to investigate the extent of esterification reaction under the same experimental conditions. However, in the positive perspective of view, this method can be used as a simple, rapid and cheap method for methylation of acidic residues under normal laboratory conditions.

  20. Complexation of NpO2+ with N-methyl-iminodiacetic Acid: in Comparison with Iminodiacetic and Dipicolinic Acids

    SciTech Connect

    Tian, Guoxin; Rao, Linfeng

    2010-10-01

    Complexation of Np(V) with N-methyl-iminodiacetic acid (MIDA) in 1 M NaClO{sub 4} solution was studied with multiple techniques including potentiometry, spectrophotometry, and microcalorimetry. The 1:2 complex, NpO{sub 2}(MIDA){sub 2}{sup 3-} was identified for the first time in aqueous solution. The correlation between its optical absorption properties and symmetry was discussed, in comparison with Np(V) complexes with two structurally related nitrilo-dicarboxylic acids, iminodiacetic acid (IDA) and dipicolinic acid (DPA). The order of the binding strength (DPA > MIDA > IDA) is explained by the difference in the structural and electronic properties of the ligands. In general, the nitrilo-dicarboxylates form stronger complexes with Np(V) than oxy-dicarboxylates due to a much more favorable enthalpy of complexation.

  1. Folic Acid Alters Methylation Profile of JAK-STAT and Long-Term Depression Signaling Pathways in Alzheimer's Disease Models.

    PubMed

    Li, Wen; Liu, Huan; Yu, Min; Zhang, Xumei; Zhang, Yan; Liu, Hongbo; Wilson, John X; Huang, Guowei

    2016-11-01

    Dementia has emerged as a major societal issue because of the worldwide aging population and the absence of any effective treatment. DNA methylation is an epigenetic mechanism that evidently plays a role in Alzheimer's disease (AD). Folate acts through one-carbon metabolism to support the methylation of multiple substrates including DNA. We aimed to test the hypothesis that folic acid supplementation alters DNA methylation profiles in AD models. Mouse Neuro-2a cells expressing human APP695 (N2a-APP cells) were incubated with folic acid (2.8-20 μmol/L). AD transgenic mice were fed either folate-deficient or control diets and gavaged daily with water or folic acid (600 μg/kg). Gene methylation profiles were determined by methylated DNA immunoprecipitation-DNA microarray (MeDIP-chip). Differentially methylated regions (DMRs) were determined by Quantitative Differentially Methylated Regions analysis, and differentially methylated genes (DMGs) carrying at least three DMRs were selected for pathway analysis. Folic acid up-regulated DNA methylation levels in N2a-APP cells and AD transgenic mouse brains. Functional network analysis of folic acid-induced DMGs in these AD models revealed subnetworks composed of 24 focus genes in the janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway and 12 focus genes in the long-term depression (LTD) signaling pathway. In conclusion, these results revealed a role for folic acid in the JAK-STAT and LTD signaling pathways which may be relevant to AD pathogenesis. This novel finding may stimulate reinvestigation of folic acid supplementation as a prophylactic or therapeutic treatment for AD.

  2. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2...-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2′-(1,2-diazenediyl)bis - and 2,2... butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2),...

  3. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2...-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2′-(1,2-diazenediyl)bis - and 2,2... butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2),...

  4. 75 FR 4292 - 2-Propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl 2-methyl-2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... AGENCY 40 CFR Part 180 2-Propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2... residues of 2-propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl 2-methyl-2... permissible level for residues of 2-propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and...

  5. Radioiodinated methyl-branched fatty acids: Evaluation of catabolites formed in vivo

    SciTech Connect

    Knapp, F.F. Jr.; Reske, S.N.; Kirsch, G.; Ambrose, K.R.; Blystone, S.L.; Goodman, M.M.

    1987-01-01

    Radioiodinated terminal iodophenyl-substituted long-chain fatty acids containing either racemic mono-methyl or geminal dimethyl-branching in the alkyl chain have been shown to exhibit delayed myocardial clearance properties which make these agents useful for the SPECT evaluation of myocardial fatty acid uptake patterns. Although the myocardial clearance rate of 15-(p-iodophenyl)-3-R,S- methylpentadecanoic acid (BMIPP) is considerably delayed, in comparison with the IPPA straight-chain analogue, analysis of the radioiodinated lipids present in the outflow tract of isolated rat hearts administered BMIPP have clearly demonstrated the presence of a polar metabolite. The synthesis of ..beta..-hydroxy fatty acids has been developed to allow investigation of the possible formation of ..beta..-hydroxy catabolites in vivo. The preparation of ..beta..-hydroxy BMIPP and ..beta..-hydroxy IPPA are described, and the possible significance of their formation in vivo discussed. 4 figs.

  6. Stimulatory Effects of Acibenzolar-S-Methyl on Chlorogenic Acids Biosynthesis in Centella asiatica Cells.

    PubMed

    Ncube, Efficient N; Steenkamp, Paul A; Madala, Ntakadzeni E; Dubery, Ian A

    2016-01-01

    Centella asiatica is a perrenial herb that grows in tropical regions with numerous medicinal properties mostly attributed to the presence of pentacyclic triterpenoids. Interestingly, this plant also possess a significant amount of phenylpropanoid-derived chlorogenic acids (CGAs) that have recently been reported to confer neuroprotective properties. In a biotechnological attempt to increase the biosynthesis of CGA-derivatives in cultured Centella cells, acibenzolar-S-methyl was applied as a xenobiotic inducer in combination with quinic acid and shikimic acid as precursor molecules. Applying a semi-targeted metabolomics-based approach, time and concentration studies were undertaken to evaluate the effect of the manipulation on cellular metabolism leading to CGA production. Phytochemical extracts were prepared using methanol and analyzed using a UHPLC-qTOF-MS platform. Data was processed and analyzed using multivariate data models. A total of four CGA-derivatives, annotated as trans-5-feruloylquinic acid, 3,5 di-caffeoylquinic acid, 3,5-O-dicaffeoyl-4-O-malonylquinic acid (irbic acid) and 3-caffeoyl, 5-feruloylquinic acid, were found to be upregulated by the acibenzolar-S-methyl treatment. To the best of our knowledge, this is the first report on the induction of CGA derivatives in this species. Contrary to expectations, the effects of precursor molecules on the levels of the CGAs were insignificant. However, a total of 16 metabolites, including CGA derivatives, were up-regulated by precursor treatment. Therefore, this study shows potential to biotechnologically manipulate C. asiatica cells to increase the production of these health beneficial CGAs.

  7. Stimulatory Effects of Acibenzolar-S-Methyl on Chlorogenic Acids Biosynthesis in Centella asiatica Cells

    PubMed Central

    Ncube, Efficient N.; Steenkamp, Paul A.; Madala, Ntakadzeni E.; Dubery, Ian A.

    2016-01-01

    Centella asiatica is a perrenial herb that grows in tropical regions with numerous medicinal properties mostly attributed to the presence of pentacyclic triterpenoids. Interestingly, this plant also possess a significant amount of phenylpropanoid-derived chlorogenic acids (CGAs) that have recently been reported to confer neuroprotective properties. In a biotechnological attempt to increase the biosynthesis of CGA-derivatives in cultured Centella cells, acibenzolar-S-methyl was applied as a xenobiotic inducer in combination with quinic acid and shikimic acid as precursor molecules. Applying a semi-targeted metabolomics-based approach, time and concentration studies were undertaken to evaluate the effect of the manipulation on cellular metabolism leading to CGA production. Phytochemical extracts were prepared using methanol and analyzed using a UHPLC-qTOF-MS platform. Data was processed and analyzed using multivariate data models. A total of four CGA-derivatives, annotated as trans-5-feruloylquinic acid, 3,5 di-caffeoylquinic acid, 3,5-O-dicaffeoyl-4-O-malonylquinic acid (irbic acid) and 3-caffeoyl, 5-feruloylquinic acid, were found to be upregulated by the acibenzolar-S-methyl treatment. To the best of our knowledge, this is the first report on the induction of CGA derivatives in this species. Contrary to expectations, the effects of precursor molecules on the levels of the CGAs were insignificant. However, a total of 16 metabolites, including CGA derivatives, were up-regulated by precursor treatment. Therefore, this study shows potential to biotechnologically manipulate C. asiatica cells to increase the production of these health beneficial CGAs. PMID:27733862

  8. Evaluation of eye irritation by S-(-)-10,11-dihydroxyfarnesic acid methyl ester secreted by Beauveria bassiana CS1029.

    PubMed

    Son, Hyeong-U; Lee, Sang-Han

    2013-10-01

    The aim of this study was to investigate whether S-(-)-10,11-dihydroxyfarnesic acid methyl ester produced by cell subtype Beauveria bassiana CS1029 causes acute toxicity when used for cosmetic purposes by performing an eye irritation test. New Zealand white (NZW) rabbits were treated with a 100 mg/dose of S-(-)-10,11-dihydroxyfarnesic acid methyl ester according to standard procedure guidelines. No significant changes in terms of ocular lesions of the cornea, turbidity of the cornea, swelling of the eyelid or ocular discharge were observed in the methyl ester-treated groups, while sodium dioctyl sulfosuccinate, a positive control, caused severe toxicity. The anatomical and pathological observations indicate that the methyl ester produced by Beauveria bassiana CS1029 did not induce eye irritation in the lenses of the rabbits. The data suggest that the methyl ester evaluated in this study has promising potential as a cosmetic ingredient that does not irritate the eye.

  9. Dissociative Electron-Ion Recombination of the Protonated Interstellar Species Glycolaldehyde, Acetic Acid, and Methyl Formate

    NASA Astrophysics Data System (ADS)

    Lawson, Patrick; Adams, Nigel

    2011-10-01

    Recently, the prebiotic molecule and primitive sugar glycolaldehyde and its structural isomers acetic acid and the abundant methyl formate have been detected in the interstellar medium(ISM). Understanding the processes involving these molecules is vital to understand the ISM, where stars are formed. The rate constants, αe, for dissociative electron-ion recombination of protonated gycolaldehyde, (HOCH2CHO)H^+, and protonated methyl formate, (HCOOCH3)H^+, have been determined at 300K in a variable temperature flowing afterglow using a Langmuir probe to determine the electron density. The αe at 300K are 3.2 x 10-7 cm^3 s-1 for protonated methyl formate and 7.5 x 10-7 cm^3 s-1 for protonated glycolaldehyde. The αe of protonated acetic acid could not be directly measured due to difficulty in producing the ion, but it appears to have a recombination rate constant, αe, on the ˜10-7 cm^3 s-1 scale. Additional temperature dependence information was obtained. The astrochemical implications of the αe measurements and protonation routes are also discussed.

  10. Asymmetric radiation-induced inclusion polymerization of 3-methyl-1,4-pentadiene in deoxycholic acid

    NASA Astrophysics Data System (ADS)

    Cataldo, Franco; Ursini, Ornella; Angelini, Giancarlo

    2010-01-01

    The radiation-induced polymerization of 3-methyl-1,3-pentadiene (3MPD) as an inclusion complex in deoxycholic acid (DOCA) has produced in good yield the optically active polymer poly(3-methyl-1,4-pentadiene) (P3MPD) whose structure and properties were studied by FT-IR spectroscopy and thermal analysis (TGA, DTG and DTA). The data show that the polymer is essentially trans-1,4-P3MPD as expected for the polymerization in constrained media. Trans-1,4-P3MPD is optically active with [ α] D values comprised between +4.3 and +5.6. The optical rotatory dispersion curve of the P3MPD is completely different from that of DOCA as expected.

  11. Jasmonic acid/methyl jasmonate accumulate in wounded soybean hypocotyls and modulate wound gene expression.

    PubMed

    Creelman, R A; Tierney, M L; Mullet, J E

    1992-06-01

    Jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are plant lipid derivatives that resemble mammalian eicosanoids in structure and biosynthesis. These compounds are proposed to play a role in plant wound and pathogen responses. Here we report the quantitative determination of JA/MeJA in planta by a procedure based on the use of [13C,2H3]MeJA as an internal standard. Wounded soybean (Glycine max [L] Merr. cv. Williams) stems rapidly accumulated MeJA and JA. Addition of MeJA to soybean suspension cultures also increased mRNA levels for three wound-responsive genes (chalcone synthase, vegetative storage protein, and proline-rich cell wall protein) suggesting a role for MeJA/JA in the mediation of several changes in gene expression associated with the plants' response to wounding.

  12. Structure-activity relationship of daptomycin analogues with substitution at (2S, 3R) 3-methyl glutamic acid position.

    PubMed

    Lin, Du'an; Lam, Hiu Yung; Han, Wenbo; Cotroneo, Nicole; Pandya, Bhaumik A; Li, Xuechen

    2017-02-01

    Daptomycin is a highly effective lipopeptide antibiotic against Gram-positive pathogens. The presence of (2S, 3R) 3-methyl glutamic acid (mGlu) in daptomycin has been found to be important to the antibacterial activity. However the role of (2S, 3R) mGlu is yet to be revealed. Herein, we reported the syntheses of three daptomycin analogues with (2S, 3R) mGlu substituted by (2S, 3R) methyl glutamine (mGln), dimethyl glutamic acid and (2S, 3R) ethyl glutamic acid (eGlu), respectively, and their antibacterial activities. The detailed synthesis of dimethyl glutamic acid was also reported.

  13. HPLC determination of acidic D-amino acids and their N-methyl derivatives in biological tissues.

    PubMed

    Tsesarskaia, Mara; Galindo, Erika; Szókán, Gyula; Fisher, George

    2009-06-01

    D-Aspartate (D-Asp) and N-methyl-D-aspartate (NMDA) occur in the neuroendocrine systems of vertebrates and invertebrates, where they play a role in hormone release and synthesis, neurotransmission, and memory and learning. N-methyl-d-glutamate (NMDG) has also been detected in marine bivalves. Several methods have been used to detect these amino acids, but they require pretreatment of tissue samples with o-phthaldialdehyde (OPA) to remove primary amino acids that interfere with the detection of NMDA and NMDG. We report here a one-step derivatization procedure with the chiral reagent N-alpha-(5-fluoro-2,4-dinitrophenyl)-(D or L)-valine amide, FDNP-Val-NH2, a close analog of Marfey's reagent but with better resolution and higher molar absorptivity. The diastereomers formed were separated by HPLC on an ODS-Hypersil column eluted with TFA/water-TFA/MeCN. UV absorption at 340 nm permitted detection levels as low as 5-10 pmol. D-Asp, NMDA and NMDG peaks were not obscured by other primary or secondary amino acids; hence pretreatment of tissues with OPA was not required. This method is highly reliable and fast (less than 40 min HPLC run). Using this method, we detected D-Asp, NMDA and NMDG in several biological tissues (octopus brain, optical lobe and bucchal mass; foot and mantle of the mollusk Scapharca broughtonii), confirming the results of other researchers.

  14. Light and acid dual-responsive organogel formation based on m-methyl red derivative.

    PubMed

    Cao, Xinhua; Gao, Aiping; Lv, Haiting; Wu, Yan; Wang, Xiuxiu; Fan, Yang

    2013-12-07

    A new gelator 1 that included m-methyl red was synthesized and fully characterized. It was found that the organogel of 1 was stable in DMSO even if the organogel was stimulated by acid or light. The organogel was thoroughly characterized using various microscopic techniques including field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV-vis and Fourier transform infrared (FTIR) spectra. The organogel exhibited tunable structures and optical properties under different stimulation. The regular nanoring structure was turned into microspheres after the organogel in DMSO was stimulated at 254 nm light or acid. At the same time, the color of molecule 1 in gel state and solution state was all changed after stimulation by light or acid. The hydrogen bonding and π-π stacking were found to be the main driving forces for gel formation. This dual-responsive gel held promise for soft materials application in upscale smart responsive materials.

  15. 6-Methyl-1,2,4-benzenetriol, a new intermediate in penicillic acid biosynthesis in Penicillium cyclopium

    SciTech Connect

    Sekiguchi, J.; Katayama, S.; Yamada, Y.

    1987-07-01

    Penicillic acid-negative mutants were obtained from a color mutant derived from Penicillium cyclopium NRRL 1888 through N-methyl-N'-nitro-N-nitrosoguanidine treatment. One mutant (SK2N6) accumulated 6-methyl-1,2,4-benzenetriol, which was not previously known to be a metabolite of P. cyclopium, in addition to orsellinic acid and orcinol. The radioactivity of (1-/sup 14/C)acetic acid was rapidly incorporated into 6-methyl-1,2,4-benzenetriol in a culture of P. cyclopium SK2N6. Moreover, the radioactivity of (/sup 14/C)6-methyl-1,2,4-benzenetriol was efficiently incorporated into penicillic acid in a culture of P. cyclopium NRRL 1888. These data indicate that 6-methyl-1,2,4-benzenetriol is a precursor for penicillic acid biosynthesis. The results on the addition of 1,4-dihydroxy-6-methoxy-2-methylbenzene, 6-methoxy-2-methylbenzoquinone (1,4), and 1-O-methylorcinol to a culture of P. cyclopium SK2N6 indicated that only the former two compounds are converted to penicillic acid. Thus, a new portion of the penicillic acid biosynthetic pathway is proposed.

  16. The development of iodine-123-methyl-branched fatty acids and their applications in nuclear cardiology

    SciTech Connect

    Knapp, F.F. Jr.; Ambrose, K.R.; Kropp, J.; Biersack, H.J.; Goodman, M.M.; Franken, P.; Reske, S.N.; Som, P.; Sloof, G.W.; Visser, F.C.

    1993-06-01

    Continued Interest in the use of iodine-1 23-labeled fatty acids for myocardial Imaging results from observations from a variety of studies that in many types of cardiac disease, regional fatty acid myocardial uptake patterns are often different than regional distribution of flow tracers. These differences may reflect alterations in important parameters of metabolism which can be useful for patient management or therapeutic strategy decision making. In addition, use of iodine-I 23-labeled fatty acid distribution may represent a unique metabolic probe to relate some aspects of the metabolism of these substrates with the regional viability of cardiac tissue. The use of such viability markers could provide important prognostic information on myocardial salvage, helping to identify patients for revascularization or angioplasty. Clinical studies are currently in progress with the iodine-123-labeled 1 5-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) fatty acid analogue at several institutions. The goals of this paper are to discuss development of the concept of metabolic trapping of fatty acids, to briefly review development and evaluation of various radioiodinated methyl-branched fatty acids and to discuss recent patient studies with iodine-123 (BMIPP) using single photon emission computerized tomography (SPECT).

  17. The development of iodine-123-methyl-branched fatty acids and their applications in nuclear cardiology

    SciTech Connect

    Knapp, F.F. Jr.; Ambrose, K.R. ); Kropp, J.; Biersack, H.J. . Inst. fuer Klinische und Experimentelle Nuklearmedizin); Goodman, M.M. . Dept. of Radiology); Franken, P. . Nuclear Medicine Dept.); Reske, S.N. (Ulm Univ. (Germany

    1993-01-01

    Continued Interest in the use of iodine-1 23-labeled fatty acids for myocardial Imaging results from observations from a variety of studies that in many types of cardiac disease, regional fatty acid myocardial uptake patterns are often different than regional distribution of flow tracers. These differences may reflect alterations in important parameters of metabolism which can be useful for patient management or therapeutic strategy decision making. In addition, use of iodine-I 23-labeled fatty acid distribution may represent a unique metabolic probe to relate some aspects of the metabolism of these substrates with the regional viability of cardiac tissue. The use of such viability markers could provide important prognostic information on myocardial salvage, helping to identify patients for revascularization or angioplasty. Clinical studies are currently in progress with the iodine-123-labeled 1 5-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) fatty acid analogue at several institutions. The goals of this paper are to discuss development of the concept of metabolic trapping of fatty acids, to briefly review development and evaluation of various radioiodinated methyl-branched fatty acids and to discuss recent patient studies with iodine-123 (BMIPP) using single photon emission computerized tomography (SPECT).

  18. Role of dioxygenase α-DOX2 and SA in basal response and in hexanoic acid-induced resistance of tomato (Solanum lycopersicum) plants against Botrytis cinerea.

    PubMed

    Angulo, Carlos; de la O Leyva, María; Finiti, Ivan; López-Cruz, Jaime; Fernández-Crespo, Emma; García-Agustín, Pilar; González-Bosch, Carmen

    2015-03-01

    Resistance of tomato (Solanum Lycopersicum) to the fungal pathogen Botrytis cinerea requires complex interplay between hormonal signalling. In this study, we explored the involvement of new oxylipins in the tomato basal and induced response to this necrotroph through the functional analysis of the tomato α-dioxygenase2 (α-DOX2)-deficient mutant divaricata. We also investigated the role of SA in the defence response against this necrotrophic fungus using SA-deficient tomato nahG plants. The plants lacking dioxigenase α-DOX2, which catalyses oxylipins production from fatty acids, were more susceptible to Botrytis, and hexanoic acid-induced resistance (Hx-IR) was impaired; hence α-DOX2 is required for both tomato defence and the enhanced protection conferred by natural inducer hexanoic acid (Hx) against B. cinerea. The divaricata plants accumulated less pathogen-induced callose and presented lower levels of jasmonic acid (JA) and 12-oxo-phytodienoic acid (OPDA) upon infection if compared to the wild type. Glutathion-S-transferase (GST) gene expression decreased and ROS production significantly increased in Botrytis-infected divaricata plants. These results indicate that absence of α-DOX2 influences the hormonal changes, oxidative burst and callose deposition that occur upon Botrytis infection in tomato. The study of SA-deficient nahG tomato plants showed that the plants with low SA levels displayed increased resistance to Botrytis, but were unable to display Hx-IR. This supports the involvement of SA in Hx-IR. NaghG plants displayed reduced callose and ROS accumulation upon infection and an increased GST expression. This reflects a positive relationship between SA and these defensive mechanisms in tomato. Finally, Hx boosted the pathogen-induced callose in nahG plants, suggesting that this priming mechanism is SA-independent. Our results support the involvement of the oxylipins pathway and SA in tomato response to Botrytis, probably through complex crosstalk of

  19. Accuracy, reproducibility, and interpretation of fatty acid methyl ester profiles of model bacterial communities

    USGS Publications Warehouse

    Kidd, Haack S.; Garchow, H.; Odelson, D.A.; Forney, L.J.; Klug, M.J.

    1994-01-01

    We determined the accuracy and reproducibility of whole-community fatty acid methyl ester (FAME) analysis with two model bacterial communities differing in composition by using the Microbial ID, Inc. (MIDI), system. The biomass, taxonomic structure, and expected MIDI-FAME profiles under a variety of environmental conditions were known for these model communities a priori. Not all members of each community could be detected in the composite profile because of lack of fatty acid 'signatures' in some isolates or because of variations (approximately fivefold) in fatty acid yield across taxa. MIDI- FAME profiles of replicate subsamples of a given community were similar in terms of fatty acid yield per unit of community dry weight and relative proportions of specific fatty acids. Principal-components analysis (PCA) of MIDI-FAME profiles resulted in a clear separation of the two different communities and a clustering of replicates of each community from two separate experiments on the first PCA axis. The first PCA axis accounted for 57.1% of the variance in the data and was correlated with fatty acids that varied significantly between communities and reflected the underlying community taxonomic structure. On the basis of our data, community fatty acid profiles can be used to assess the relative similarities and differences of microbial communities that differ in taxonomic composition. However, detailed interpretation of community fatty acid profiles in terms of biomass or community taxonomic composition must be viewed with caution until our knowledge of the quantitative and qualitative distribution of fatty acids over a wide variety of taxa and the effects of growth conditions on fatty acid profiles is more extensive.

  20. XAS and RIXS study of acetic acid and methyl formate in liquid

    NASA Astrophysics Data System (ADS)

    Takahashi, O.; Nishida, N.; Kanai, S.; Horikawa, Y.; Tokushima, T.

    2016-05-01

    Structure of acetic acid (AA) and methyl formate (MF) in the liquid phase is studied using X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) experimentally and theoretically. Two distinct XES spectra are observed by tuning photon energy for both molecules. Model structure in the liquid phase is constructed using the classical and first principle molecular dynamics simulations, and XES spectra are calculated using density functional theory. Calculated XES spectra are consistent with experimental ones. The effect of core-hole induced excited state molecular dynamics are discussed.

  1. Enzymatic synthesis of radioactive (-)-carnitine from. gamma. -butyrobetaine prepared by the methylation of. gamma. -aminobutyric acid

    SciTech Connect

    Daveluy, A.; Parvin, R.; Pande, S.V.

    1982-01-15

    Radioactive ..gamma..-butyrobetaine was prepared by quaternization of ..gamma..-aminobutyric acid with tritiated methyl iodide under conditions giving high yields with respect to both the above precursors. Part of the product was passed through a column of ion-retardation resin and gave radioactive ..gamma..-butyrobetaine of good purity. The remainder was converted to (-)-carnitine stoichiometrically by employing a 50-60% ammonium sulfate fraction of rat liver supernatant as the source of ..gamma..-butyrobetaine hydroxylase (EC 1,14,11,1) Successive column chromatographies on a cation exchanger and ion-retardation resins then gave radioactive (-)-carnitine of good purity in high yield.

  2. Radiation chemistry of salicylic and methyl substituted salicylic acids: Models for the radiation chemistry of pharmaceutical compounds

    NASA Astrophysics Data System (ADS)

    Ayatollahi, Shakiba; Kalnina, Daina; Song, Weihua; Turks, Maris; Cooper, William J.

    2013-11-01

    Salicylic acid and its derivatives are components of many medications and moieties found in numerous pharmaceutical compounds. They have been used as models for various pharmaceutical compounds in pharmacological studies, for the treatment of pharmaceuticals and personal care products (PPCPs), and, reactions with natural organic matter (NOM). In this study, the radiation chemistry of benzoic acid, salicylic acid and four methyl substituted salicylic acids (MSA) is reported. The absolute bimolecular reaction rate constants for hydroxyl radical reaction with benzoic and salicylic acids as well as 3-methyl-, 4-methyl-, 5-methyl-, and 6-methyl-salicylic acid were determined (5.86±0.54)×109, (1.07±0.07)×1010, (7.48±0.17)×109, (7.31±0.29)×109, (5.47±0.25)×109, (6.94±0.10)×109 (M-1 s-1), respectively. The hydrated electron reaction rate constants were measured (3.02±0.10)×109, (8.98±0.27)×109, (5.39±0.21)×109, (4.33±0.17)×109, (4.72±0.15)×109, (1.42±0.02)×109 (M-1 s-1), respectively. The transient absorption spectra for the six model compounds were examined and their role as model compounds for the radiation chemistry of pharmaceuticals investigated.

  3. Esterification Reaction of Glycerol and Palm Oil Oleic Acid Using Methyl Ester Sulfonate Acid Catalyst as Drilling Fluid Formulation

    NASA Astrophysics Data System (ADS)

    Sari, V. I.; Hambali, E.; Suryani, A.; Permadi, P.

    2017-02-01

    Esterification reaction between glycerol with palm oil oleic acid to produce glycerol ester and one of the utilization of glycerol esters is as ingredients of drilling fluids formula for oil drilling needs. The purpose of this research is to get the best conditions of the esterification process. The esterification reaction does with the reactants is glycerol with purity of 97.6%, palm oil oleic acid with the molar ratio is 1:1, Methyl Ester Sulfonate Acid (MESA) catalyst 0.5%, and stirring speed 400 rpm. The temperature range of 180°C to 240°C and the processing time between 120 to 180 minutes. The results showed that the best conditions of the esterification reaction at the temperature 240°C and time process are 180 minute. The increasing temperature resulted that the acid number decreases and causing the conversion increased. The maximum conversion is 99.24%, density 0.93 g/cm3, flash point 241°C, pour point -3°C, the boiling point of 244 °C, the acid value of 1.90 mg KOH/g sample, kinematic viscosity 31.51 cSt (40°C), surface tension 37.0526 dyne/cm and GCMS identification, glycerol ester at 22,256 retention time (minutes) and wide area 73.75 (%). From the research results obtained glycerol ester with characteristics suitable for drilling fluid formulations.

  4. Adsorption of methyl orange and salicylic acid on a nano-transition metal composite: Kinetics, thermodynamic and electrochemical studies.

    PubMed

    Arshadi, M; Mousavinia, F; Amiri, M J; Faraji, A R

    2016-12-01

    In this work synthesis of Mn-nanoparticles (MnNPs) supported on the Schiff base modified nano-sized SiO2Al2O3 mixed-oxides (Si/Al) and its implementation as an adsorbent for the removal of organic pollutions such as methyl orange (MO) and salicylic acid (SA) was investigated. Si/Al were functionalized by grafting Schiff base ligand and in the next step, MnNPs were prepared over the modified nano sol-gel Si/Al. Structures and adsorption characteristics of the obtained organometallic-modified SiO2/Al2O3 mixed oxide were studied by several methods such as elemental analysis, diffuse reflectance UV-vis spectroscopy, FT-IR spectroscopy, nitrogen adsorption/desorption, scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), inductively coupled plasma (ICP-AES), Electron Paramagnetic Resonance (EPR), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). EPR data of the immobilized manganese ions resulted that the transition state of active sites in the nano-adsorbent are in the form of Mn(II) ions at the surface. The adsorption properties of heterogeneous Mn(II) ions showed that this nano-adsorbent has very good potential to remove MO and SA ions from aqueous solution. The removal efficiency of the SAPAS@MnNPs towards MO reached out to 89.3 and 29.1% and for SA approached to 54.6 and 18.9% at 150 and 500mg/dm(3) initial organic pollution concentrations, respectively. To investigate the adsorption kinetic of Mn(II) ions onto the nano-sized support, pseudo first and pseudo second order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The contact time to obtain equilibrium for maximum adsorption capacity was 45min. The adsorption process was spontaneous and endothermic in nature and it was well explained with pseudo-second-order kinetic model. No remarkable loss of removal capacity even after 8th times regeneration

  5. Production of Fatty Acid Methyl Esters via the In Situ Transesterification of Soybean Oil in Carbon Dioxide-Expanded Methanol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The production of fatty acid methyl esters (FAME) by direct alkali- and acid-catalyzed in situ transesterification of soybean flakes in CO2-expanded methanol was examined at various temperatures and pressures. Attempts to synthesize FAME from soy flakes via alkaline catalysis, using sodium methoxid...

  6. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... from edible fats and oils. 172.225 Section 172.225 Food and Drugs FOOD AND DRUG ADMINISTRATION... acids produced from edible fats and oils. Methyl esters and ethyl esters of fatty acids produced from edible fats and oils may be safely used in food, subject to the following prescribed conditions: (a)...

  7. Bis-(2-amino-5-methyl-pyridinium) fumarate-fumaric acid (1/1).

    PubMed

    Hemamalini, Madhukar; Fun, Hoong-Kun

    2010-07-24

    In the crystal structure of the title compound, C(6)H(9)N(2) (+)·0.5C(4)H(2)O(4) (2-)·0.5C(4)H(6)O(4), the fumarate dianion and fumaric acid mol-ecule are located on inversion centres. The 2-amino-5-methyl-pyrimidinium cation inter-acts with the carboxyl-ate group of the fumarate anion through a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. These motifs are centrosymmetrically paired via N-H⋯O hydrogen bonds, forming a complementary DDAA array. The carboxyl groups of the fumaric acid mol-ecules and the carboxyl-ate groups of the fumarate anions are hydrogen bonded through O-H⋯O hydrogen bonds, leading to a supra-molecular chain along [101]. The crystal structure is further stabilized by weak C-H⋯O hydrogen bonds.

  8. N-( p-Ethynylbenzoyl) derivatives of amino acid and dipeptide methyl esters - Synthesis and structural study

    NASA Astrophysics Data System (ADS)

    Eißmann, Frank; Weber, Edwin

    2011-11-01

    A series of N-( p-ethynylbenzoyl) derivatives ( 1-4) of the amino acids glycine and L-alanine as well as the dipeptides glycylglycine and L-alanylglycine has been synthesized via a two-step reaction sequence including the reaction of an appropriate N-( p-bromobenzoyl) precursor with trimethylsilylacetylene followed by deprotection of the trimethylsilyl protecting group, respectively. X-ray crystal structures of the amino acid and dipeptide methyl esters 1-4 are reported. The amide and peptide bonds within each molecular structure are planar and adopt the trans-configuration. The packing structures are governed by N sbnd H⋯O interactions leading to the formation of characteristic strand motifs. Further stabilization results from weaker C sbnd H⋯O and C sbnd H⋯π contacts.

  9. A monolithic lipase reactor for biodiesel production by transesterification of triacylglycerides into fatty acid methyl esters

    PubMed Central

    Urban, Jiri; Svec, Frantisek; Fréchet, Jean M.J.

    2011-01-01

    An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. PMID:21915852

  10. A monolithic lipase reactor for biodiesel production by transesterification of triacylglycerides into fatty acid methyl esters.

    PubMed

    Urban, Jiri; Svec, Frantisek; Fréchet, Jean M J

    2012-02-01

    An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel.

  11. Phytic acid suppresses 1-methyl-4-phenylpyridinium ion-induced hydroxyl radical generation in rat striatum.

    PubMed

    Obata, Toshio

    2003-07-18

    The present study examined the antioxidant effect of phytic acid on iron (II)-enhanced hydroxyl radical (*OH) generation induced by 1-methyl-4-phenylpyridinium ion (MPP(+)) in the extracellular fluid of rat striatum. Rats were anesthetized, and sodium salicylate in Ringer's solution (0.5 nmol/microl/min) was infused through a microdialysis probe to detect the generation of *OH as reflected by the non-enzymatic formation of 2,3-dihydroxybenzoic acid (DHBA) in the striatum. Phytic acid (100 microM) did not significantly decrease the levels of MPP(+)-induced *OH formation trapped as 2,3-DHBA. To confirm the generation of *OH by the Fenton-type reaction, iron (II) was infused through a microdialysis probe. Introduction of iron (II) (10 microM) enhanced MPP(+) induced *OH generation. However, phytic acid significantly suppressed iron (II)-enhanced *OH formation after MPP(+) treatment (n=6, P<0.05). These results suggest that the antiradical effect of phytic acid occurs by chelating iron required for the MPP(+)-enhanced *OH generation via the Fenton-type reaction.

  12. Neuroprotective Effect of Tauroursodeoxycholic Acid on N-Methyl-D-Aspartate-Induced Retinal Ganglion Cell Degeneration

    PubMed Central

    Fernández-Sánchez, Laura; Rondón, Netxibeth; Esquiva, Gema; Germain, Francisco; de la Villa, Pedro; Cuenca, Nicolás

    2015-01-01

    Retinal ganglion cell degeneration underlies the pathophysiology of diseases affecting the retina and optic nerve. Several studies have previously evidenced the anti-apoptotic properties of the bile constituent, tauroursodeoxycholic acid, in diverse models of photoreceptor degeneration. The aim of this study was to investigate the effects of systemic administration of tauroursodeoxycholic acid on N-methyl-D-aspartate (NMDA)-induced damage in the rat retina using a functional and morphological approach. Tauroursodeoxycholic acid was administered intraperitoneally before and after intravitreal injection of NMDA. Three days after insult, full-field electroretinograms showed reductions in the amplitudes of the positive and negative-scotopic threshold responses, scotopic a- and b-waves and oscillatory potentials. Quantitative morphological evaluation of whole-mount retinas demonstrated a reduction in the density of retinal ganglion cells. Systemic administration of tauroursodeoxycholic acid attenuated the functional impairment induced by NMDA, which correlated with a higher retinal ganglion cell density. Our findings sustain the efficacy of tauroursodeoxycholic acid administration in vivo, suggesting it would be a good candidate for the pharmacological treatment of degenerative diseases coursing with retinal ganglion cell loss. PMID:26379056

  13. Neuroprotective Effect of Tauroursodeoxycholic Acid on N-Methyl-D-Aspartate-Induced Retinal Ganglion Cell Degeneration.

    PubMed

    Gómez-Vicente, Violeta; Lax, Pedro; Fernández-Sánchez, Laura; Rondón, Netxibeth; Esquiva, Gema; Germain, Francisco; de la Villa, Pedro; Cuenca, Nicolás

    2015-01-01

    Retinal ganglion cell degeneration underlies the pathophysiology of diseases affecting the retina and optic nerve. Several studies have previously evidenced the anti-apoptotic properties of the bile constituent, tauroursodeoxycholic acid, in diverse models of photoreceptor degeneration. The aim of this study was to investigate the effects of systemic administration of tauroursodeoxycholic acid on N-methyl-D-aspartate (NMDA)-induced damage in the rat retina using a functional and morphological approach. Tauroursodeoxycholic acid was administered intraperitoneally before and after intravitreal injection of NMDA. Three days after insult, full-field electroretinograms showed reductions in the amplitudes of the positive and negative-scotopic threshold responses, scotopic a- and b-waves and oscillatory potentials. Quantitative morphological evaluation of whole-mount retinas demonstrated a reduction in the density of retinal ganglion cells. Systemic administration of tauroursodeoxycholic acid attenuated the functional impairment induced by NMDA, which correlated with a higher retinal ganglion cell density. Our findings sustain the efficacy of tauroursodeoxycholic acid administration in vivo, suggesting it would be a good candidate for the pharmacological treatment of degenerative diseases coursing with retinal ganglion cell loss.

  14. A non-canonical peptide synthetase adenylates 3-methyl-2-oxovaleric acid for auriculamide biosynthesis

    PubMed Central

    Braga, Daniel; Hoffmeister, Dirk

    2016-01-01

    Auriculamide is the first natural product known from the predatory bacterium Herpetosiphon aurantiacus. It is composed of three unusual building blocks, including the non-proteinogenic amino acid 3-chloro-L-tyrosine, the α-hydroxy acid L-isoleucic acid, and a methylmalonyl-CoA-derived ethane unit. A candidate genetic locus for auriculamide biosynthesis was identified and encodes four enzymes. Among them, the non-canonical 199 kDa four-domain nonribosomal peptide synthetase, AulA, is extraordinary in that it features two consecutive adenylation domains. Here, we describe the functional characterization of the recombinantly produced AulA. The observed activation of 3-methyl-2-oxovaleric acid by the enzyme supports the hypothesis that it participates in the biosynthesis of auriculamide. An artificially truncated version of AulA that lacks the first adenylation domain activated this substrate like the full-length enzyme which shows that the first adenylation domain is dispensable. Additionally, we provide evidence that the enzyme tolerates structural variation of the substrate. α-Carbon substituents significantly affected the substrate turnover. While all tested aliphatic α-keto acids were accepted by the enzyme and minor differences in chain size and branches did not interfere with the enzymatic activity, molecules with methylene α-carbons led to low turnover. Such enzymatic plasticity is an important attribute to help in the perpetual search for novel molecules and to access a greater structural diversity by mutasynthesis. PMID:28144348

  15. Supported phosphate and carbonate salts for heterogeneous catalysis of triglycerides to fatty acid methyl esters

    NASA Astrophysics Data System (ADS)

    Britton, Stephanie Lynne

    Fatty acid methyl esters made from vegetable oil, or biodiesel, have been identified as a substitute for diesel derived from crude oil. Biodiesel is currently made using a homogeneous base catalyst to perform the transesterification of triglycerides with methanol to generate fatty acid methyl esters (FAME). The use of a homogeneous catalyst necessitates additional purification of the product and byproducts before sale, and the catalyst is consumed and discarded. The development of a heterogeneous basic catalyst for the production of FAME is desirable. Tribasic phosphate salts and dibasic carbonate salts are active for the production of FAME but generally operate as homogeneous catalysts. Supporting these phosphate and carbonate salts on mesoporous MCM-41, microporous silica gel, and nonporous a-alumina proved successful to greater or lesser degrees depending on the identity of the support and pretreatment of the support. Although these salts were supported and were active for the production of FAME from canola oil, they proved to be operating as homogeneous catalysts due to leaching of the active species off the surface of the support. Further investigation of the active species present in the tribasic phosphate catalysts identified the active support as orthophosphate, and NMR studies revealed the phosphorus to be present as orthophosphate and diphosphate in varying proportions in each catalyst. Evaluation of the acid-washing support pretreatment process revealed that the exposure of the support to acid plays a large role in the development of activity on the surface of the catalyst, but manipulation of these parameters did not prevent leaching of the active site off the surface of the catalyst. Alternate methods of support pretreatment were no more effective in preventing leaching. Tribasic phosphate supported on silica gel is not effective as a heterogeneous catalyst for FAME production from triglycerides because of the lack of stability of the phosphate on the

  16. A single amino acid substitution confers enhanced methylation activity of mammalian Dnmt3b on chromatin DNA.

    PubMed

    Shen, Li; Gao, Ge; Zhang, Ying; Zhang, He; Ye, Zhiqiang; Huang, Shichao; Huang, Jinyan; Kang, Jiuhong

    2010-10-01

    Dnmt3a and Dnmt3b are paralogous enzymes responsible for de novo DNA methylation but with distinguished biological functions. In mice, disruption of Dnmt3b but not Dnmt3a causes global DNA hypomethylation, especially in repetitive sequences, which comprise the large majority of methylated DNA in the genome. By measuring DNA methylation activity of Dnmt3a and Dnmt3b homologues from five species, we found that mammalian Dnmt3b possessed significantly higher methylation activity on chromatin DNA than Dnmt3a and non-mammalian Dnmt3b. Sequence comparison and mutagenesis experiments identified a single amino acid substitution (I662N) in mammalian Dnmt3b as being crucial for its high chromatin DNA methylation activity. Further mechanistic studies demonstrated this substitution markedly enhanced the binding of Dnmt3b to nucleosomes and hence increased the chromatin DNA methylation activity. Moreover, this substitution was crucial for Dnmt3b to efficiently methylate repetitive sequences, which increased dramatically in mammalian genomes. Consistent with our observation that Dnmt3b evolved more rapidly than Dnmt3a during the emergence of mammals, these results demonstrated that the I662N substitution in mammalian Dnmt3b conferred enhanced chromatin DNA methylation activity and contributed to functional adaptation in the epigenetic system.

  17. DNA Methylation Profiling at Single-Base Resolution Reveals Gestational Folic Acid Supplementation Influences the Epigenome of Mouse Offspring Cerebellum

    PubMed Central

    Barua, Subit; Kuizon, Salomon; Brown, W. Ted; Junaid, Mohammed A.

    2016-01-01

    It is becoming increasingly more evident that lifestyle, environmental factors, and maternal nutrition during gestation can influence the epigenome of the developing fetus and thus modulate the physiological outcome. Variations in the intake of maternal nutrients affecting one-carbon metabolism may influence brain development and exert long-term effects on the health of the progeny. In this study, we investigated whether supplementation with high maternal folic acid during gestation alters DNA methylation and gene expression in the cerebellum of mouse offspring. We used reduced representation bisulfite sequencing to analyze the DNA methylation profile at the single-base resolution level. The genome-wide DNA methylation analysis revealed that supplementation with higher maternal folic acid resulted in distinct methylation patterns (P < 0.05) of CpG and non-CpG sites in the cerebellum of offspring. Such variations of methylation and gene expression in the cerebellum of offspring were highly sex-specific, including several genes of the neuronal pathways. These findings demonstrate that alterations in the level of maternal folic acid during gestation can influence methylation and gene expression in the cerebellum of offspring. Such changes in the offspring epigenome may alter neurodevelopment and influence the functional outcome of neurologic and psychiatric diseases. PMID:27199632

  18. Genome-Wide Methylation and Gene Expression Changes in Newborn Rats following Maternal Protein Restriction and Reversal by Folic Acid

    PubMed Central

    Stupka, Elia; Clark, Adrian J. L.; Langley-Evans, Simon

    2013-01-01

    A large body of evidence from human and animal studies demonstrates that the maternal diet during pregnancy can programme physiological and metabolic functions in the developing fetus, effectively determining susceptibility to later disease. The mechanistic basis of such programming is unclear but may involve resetting of epigenetic marks and fetal gene expression. The aim of this study was to evaluate genome-wide DNA methylation and gene expression in the livers of newborn rats exposed to maternal protein restriction. On day one postnatally, there were 618 differentially expressed genes and 1183 differentially methylated regions (FDR 5%). The functional analysis of differentially expressed genes indicated a significant effect on DNA repair/cycle/maintenance functions and of lipid, amino acid metabolism and circadian functions. Enrichment for known biological functions was found to be associated with differentially methylated regions. Moreover, these epigenetically altered regions overlapped genetic loci associated with metabolic and cardiovascular diseases. Both expression changes and DNA methylation changes were largely reversed by supplementing the protein restricted diet with folic acid. Although the epigenetic and gene expression signatures appeared to underpin largely different biological processes, the gene expression profile of DNA methyl transferases was altered, providing a potential link between the two molecular signatures. The data showed that maternal protein restriction is associated with widespread differential gene expression and DNA methylation across the genome, and that folic acid is able to reset both molecular signatures. PMID:24391732

  19. Synthesis and evaluation of anti-oxidant and cytotoxic activities of novel 10-undecenoic acid methyl ester based lipoconjugates of phenolic acids

    PubMed Central

    Narra, Naganna; Prasad, Rachapudi Badari Narayana; Misra, Sunil; Dhevendar, Koude; Kontham, Venkateshwarlu

    2017-01-01

    The synthesis of five novel methyl 10-undecenoate-based lipoconjugates of phenolic acids from undecenoic acid was carried out. Undecenoic acid was methylated to methyl 10-undecenoate which was subjected to a thiol–ene reaction with cysteamine hydrochloride. Further amidation of the amine was carried out with different phenolic acids such as caffeic, ferulic, sinapic, coumaric and cinnamic acid. All synthesized compounds were fully characterized and their structures were confirmed by spectral data. The anti-oxidant activity of the synthesized lipoconjugates of phenolic acids was studied by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and also by the inhibition of linoleic acid oxidation in micellar medium by differential scanning calorimetry (DSC). The prepared compounds were also screened for their cytotoxic activity against five cell lines. It was observed that the lipoconjugates of caffeic acid, sinapic acid, ferulic acid, and coumaric acid displayed anticancer and anti-oxidant properties. The anticancer properties of these derivatives have been assessed by their IC50 inhibitory values in the proliferation of MDA-MB231, SKOV3, MCF7, DU 145 and HepG2 cancer cell lines. PMID:28179945

  20. Site-Directed Mutagenesis of HgcA and HgcB Reveals Amino Acid Residues Important for Mercury Methylation

    PubMed Central

    Smith, Steven D.; Bridou, Romain; Johs, Alexander; Parks, Jerry M.; Elias, Dwayne A.; Hurt, Richard A.; Brown, Steven D.; Podar, Mircea

    2015-01-01

    Methylmercury is a potent neurotoxin that is produced by anaerobic microorganisms from inorganic mercury by a recently discovered pathway. A two-gene cluster, consisting of hgcA and hgcB, encodes two of the proteins essential for this activity. hgcA encodes a corrinoid protein with a strictly conserved cysteine proposed to be the ligand for cobalt in the corrinoid cofactor, whereas hgcB encodes a ferredoxin-like protein thought to be an electron donor to HgcA. Deletion of either gene eliminates mercury methylation by the methylator Desulfovibrio desulfuricans ND132. Here, site-directed mutants of HgcA and HgcB were constructed to determine amino acid residues essential for mercury methylation. Mutations of the strictly conserved residue Cys93 in HgcA, the proposed ligand for the corrinoid cobalt, to Ala or Thr completely abolished the methylation capacity, but a His substitution produced measurable methylmercury. Mutations of conserved amino acids near Cys93 had various impacts on the methylation capacity but showed that the structure of the putative “cap helix” region harboring Cys93 is crucial for methylation function. In the ferredoxin-like protein HgcB, only one of two conserved cysteines found at the C terminus was necessary for methylation, but either cysteine sufficed. An additional, strictly conserved cysteine, Cys73, was also determined to be essential for methylation. This study supports the previously predicted importance of Cys93 in HgcA for methylation of mercury and reveals additional residues in HgcA and HgcB that facilitate the production of this neurotoxin. PMID:25724962

  1. Site-Directed Mutagenesis of HgcA and HgcB Reveals Amino Acid Residues Important for Mercury Methylation

    DOE PAGES

    Smith, Steven D.; Bridou, Romain; Johs, Alexander; ...

    2015-02-27

    Methylmercury is a potent neurotoxin that is produced by anaerobic microorganisms from inorganic mercury by a recently discovered pathway. A two-gene cluster, consisting of hgcA and hgcB, encodes two of the proteins essential for this activity. hgcA encodes a corrinoid protein with a strictly conserved cysteine proposed to be the ligand for cobalt in the corrinoid cofactor, whereas hgcB encodes a ferredoxin-like protein thought to be an electron donor to HgcA. Deletion of either gene eliminates mercury methylation by the methylator Desulfovibrio desulfuricans ND132. Here, site-directed mutants of HgcA and HgcB were constructed to determine amino acid residues essential formore » mercury methylation. Mutations of the strictly conserved residue Cys93 in HgcA, the proposed ligand for the corrinoid cobalt, to Ala or Thr completely abolished the methylation capacity, but a His substitution produced measurable methylmercury. Mutations of conserved amino acids near Cys93 had various impacts on the methylation capacity but showed that the structure of the putative “cap helix” region harboring Cys93 is crucial for methylation function. In the ferredoxin-like protein HgcB, only one of two conserved cysteines found at the C terminus was necessary for methylation, but either cysteine sufficed. An additional, strictly conserved cysteine, Cys73, was also determined to be essential for methylation. Ultimately, this study supports the previously predicted importance of Cys93 in HgcA for methylation of mercury and reveals additional residues in HgcA and HgcB that facilitate the production of this neurotoxin.« less

  2. Site-Directed Mutagenesis of HgcA and HgcB Reveals Amino Acid Residues Important for Mercury Methylation

    SciTech Connect

    Smith, Steven D.; Bridou, Romain; Johs, Alexander; Parks, Jerry M.; Elias, Dwayne A.; Hurt, Richard A.; Brown, Steven D.; Podar, Mircea; Wall, Judy D.

    2015-02-27

    Methylmercury is a potent neurotoxin that is produced by anaerobic microorganisms from inorganic mercury by a recently discovered pathway. A two-gene cluster, consisting of hgcA and hgcB, encodes two of the proteins essential for this activity. hgcA encodes a corrinoid protein with a strictly conserved cysteine proposed to be the ligand for cobalt in the corrinoid cofactor, whereas hgcB encodes a ferredoxin-like protein thought to be an electron donor to HgcA. Deletion of either gene eliminates mercury methylation by the methylator Desulfovibrio desulfuricans ND132. Here, site-directed mutants of HgcA and HgcB were constructed to determine amino acid residues essential for mercury methylation. Mutations of the strictly conserved residue Cys93 in HgcA, the proposed ligand for the corrinoid cobalt, to Ala or Thr completely abolished the methylation capacity, but a His substitution produced measurable methylmercury. Mutations of conserved amino acids near Cys93 had various impacts on the methylation capacity but showed that the structure of the putative “cap helix” region harboring Cys93 is crucial for methylation function. In the ferredoxin-like protein HgcB, only one of two conserved cysteines found at the C terminus was necessary for methylation, but either cysteine sufficed. An additional, strictly conserved cysteine, Cys73, was also determined to be essential for methylation. Ultimately, this study supports the previously predicted importance of Cys93 in HgcA for methylation of mercury and reveals additional residues in HgcA and HgcB that facilitate the production of this neurotoxin.

  3. Methyl jasmonate stimulates biosynthesis of 2-phenylethylamine, phenylacetic acid and 2-phenylethanol in seedlings of common buckwheat.

    PubMed

    Horbowicz, Marcin; Wiczkowski, Wiesław; Sawicki, Tomasz; Szawara-Nowak, Dorota; Sytykiewicz, Hubert; Mitrus, Joanna

    2015-01-01

    Methyl jasmonate has a strong effect on secondary metabolizm in plants, by stimulating the biosynthesis a number of phenolic compounds and alkaloids. Common buckwheat (Fagopyrum esculentum Moench) is an important source of biologically active compounds. This research focuses on the detection and quantification of 2-phenylethylamine and its possible metabolites in the cotyledons, hypocotyl and roots of common buckwheat seedlings treated with methyl jasmonate. In cotyledons of buckwheat sprouts, only traces of 2-phenylethylamine were found, while in the hypocotyl and roots its concentration was about 150 and 1000-times higher, respectively. Treatment with methyl jasmonate resulted in a 4-fold increase of the 2-phenylethylamine level in the cotyledons of 7-day buckwheat seedlings, and an 11-fold and 5-fold increase in hypocotyl and roots, respectively. Methyl jasmonate treatment led also to about 4-fold increase of phenylacetic acid content in all examined seedling organs, but did not affect the 2-phenylethanol level in cotyledons, and slightly enhanced in hypocotyl and roots. It has been suggested that 2-phenylethylamine is a substrate for the biosynthesis of phenylacetic acid and 2-phenylethanol, as well as cinnamoyl 2-phenethylamide. In organs of buckwheat seedling treated with methyl jasmonate, higher amounts of aromatic amino acid transaminase mRNA were found. The enzyme can be involved in the synthesis of phenylpyruvic acid, but the presence of this compound could not be confirmed in any of the examined organs of common buckwheat seedling.

  4. Effects of radiation, acid, and base on the extractant dihexyl-(diethylcarbamoyl)methyl) phosphonate

    SciTech Connect

    Bahner, C.T.; Shoun, R.R.; McDowell, W.J.

    1981-11-01

    The effects of exposure to gamma radiation (/sup 60/Co) and of contact with acidic and basic aqueous solutions on dihexyl((diethylcarbamoyl)methyl)phosphonate (DHDECMP) were studied. Gamma radiation decomposes DHDECMP into a variety of products. The most troublesome of those are the acidic compounds that cause problems in stripping the actinides and lanthanides from the extractant at low acid concentrations. The rate of degradation of DHDECMP by radiation is about the same or only slightly higher than that of tri-n-butyl phosphate (TBP). It is relatively easy to remove the radiation-produced impurities by equilibration (scrubbing) with sodium carbonate or sodium hydroxide or by column chromatographic methods. The hydrolysis of DHDECMP in contact with aqueous solutions containing less than 3 M HNO/sub 3/ is not more severe than that of TBP under the same conditions but is significant above that acid concentration. Hydrolysis of DHDECMP in contact with aqueous sodium hydroxide solution does occur, but it should not pose an important problem with the short contact times such as those anticipated for the removal of the radiation-induced degradation products by caustic scrubbing. Results of various chromatographic tests to characterize the degradation products of DHDECMP are also given.

  5. Rapid Photodegradation of Methyl Orange (MO) Assisted with Cu(II) and Tartaric Acid

    PubMed Central

    Guo, Jing; Chen, Xue; Shi, Ying; Lan, Yeqing; Qin, Chao

    2015-01-01

    Cu(II) and organic carboxylic acids, existing extensively in soil and aquatic environments, can form complexes that may play an important role in the photodegradation of organic contaminants. In this paper, the catalytic role of Cu(II) in the removal of methyl orange (MO) in the presence of tartaric acid with light was investigated through batch experiments. The results demonstrate that the introduction of Cu(II) could markedly enhance the photodegradation of MO. In addition, high initial concentrations of Cu(II) and tartaric acid benefited the decomposition of MO. The most rapid removal of MO assisted by Cu(II) was achieved at pH 3. The formation of Cu(II)-tartaric acid complexes was assumed to be the key factor, generating hydroxyl radicals (•OH) and other oxidizing free radicals under irradiation through a ligand-to-metal charge-transfer pathway that was responsible for the efficient degradation of MO. Some intermediates in the reaction system were also detected to support this reaction mechanism. PMID:26241043

  6. Hydrolase BioH knockout in E. coli enables efficient fatty acid methyl ester bioprocessing.

    PubMed

    Kadisch, Marvin; Schmid, Andreas; Bühler, Bruno

    2017-03-01

    Fatty acid methyl esters (FAMEs) originating from plant oils are most interesting renewable feedstocks for biofuels and bio-based materials. FAMEs can also be produced and/or functionalized by engineered microbes to give access to, e.g., polymer building blocks. Yet, they are often subject to hydrolysis yielding free fatty acids, which typically are degraded by microbes. We identified BioH as the key enzyme responsible for the hydrolysis of medium-chain length FAME derivatives in different E. coli K-12 strains. E. coli ΔbioH strains showed up to 22-fold reduced FAME hydrolysis rates in comparison with respective wild-type strains. Knockout strains showed, beside the expected biotin auxotrophy, unchanged growth behavior and biocatalytic activity. Thus, high specific rates (~80 U g CDW(-1) ) for terminal FAME oxyfunctionalization catalyzed by a recombinant alkane monooxygenase could be combined with reduced hydrolysis. Biotransformations in process-relevant two-liquid phase systems profited from reduced fatty acid accumulation and/or reduced substrate loss via free fatty acid metabolization. The BioH knockout strategy was beneficial in all tested strains, although its effect was found to differ according to specific strain properties, such as FAME hydrolysis and FFA degradation activities. BioH or functional analogs can be found in virtually all microorganisms, making bioH deletion a broadly applicable strategy for efficient microbial bioprocessing involving FAMEs.

  7. Rapid Photodegradation of Methyl Orange (MO) Assisted with Cu(II) and Tartaric Acid.

    PubMed

    Guo, Jing; Chen, Xue; Shi, Ying; Lan, Yeqing; Qin, Chao

    2015-01-01

    Cu(II) and organic carboxylic acids, existing extensively in soil and aquatic environments, can form complexes that may play an important role in the photodegradation of organic contaminants. In this paper, the catalytic role of Cu(II) in the removal of methyl orange (MO) in the presence of tartaric acid with light was investigated through batch experiments. The results demonstrate that the introduction of Cu(II) could markedly enhance the photodegradation of MO. In addition, high initial concentrations of Cu(II) and tartaric acid benefited the decomposition of MO. The most rapid removal of MO assisted by Cu(II) was achieved at pH 3. The formation of Cu(II)-tartaric acid complexes was assumed to be the key factor, generating hydroxyl radicals (•OH) and other oxidizing free radicals under irradiation through a ligand-to-metal charge-transfer pathway that was responsible for the efficient degradation of MO. Some intermediates in the reaction system were also detected to support this reaction mechanism.

  8. Cisplatin-incorporated nanoparticles of poly(acrylic acid-co-methyl methacrylate) copolymer

    PubMed Central

    Lee, Kyung Dong; Jeong, Young-Il; Kim, Da Hye; Lim, Gyun-Taek; Choi, Ki-Choon

    2013-01-01

    Background Although cisplatin is extensively used in the clinical field, its intrinsic toxicity limits its clinical use. We investigated nanoparticle formations of poly(acrylic acid-co-methyl methacrylate) (PAA-MMA) incorporating cisplatin and their antitumor activity in vitro and in vivo. Methods Cisplatin-incorporated nanoparticles were prepared through the ion-complex formation between acrylic acid and cisplatin. The anticancer activity of cisplatin-incorporated nanoparticles was assessed with CT26 colorectal carcinoma cells. Results Cisplatin-incorporated nanoparticles have small particle sizes of less than 200 nm with spherical shapes. Drug content was increased according to the increase of the feeding amount of cisplatin and acrylic acid content in the copolymer. The higher acrylic acid content in the copolymer induced increase of particle size and decrease of zeta potential. Cisplatin-incorporated nanoparticles showed a similar growth-inhibitory effect against CT26 tumor cells in vitro. However, cisplatin-incorporated nanoparticles showed improved antitumor activity against an animal tumor xenograft model. Conclusion We suggest that PAA-MMA nanoparticles incorporating cisplatin are promising carriers for an antitumor drug-delivery system. PMID:23966778

  9. Candida rugosa Lipase Immobilized onto Acid-Functionalized Multi-walled Carbon Nanotubes for Sustainable Production of Methyl Oleate.

    PubMed

    Che Marzuki, Nur Haziqah; Mahat, Naji Arafat; Huyop, Fahrul; Buang, Nor Aziah; Wahab, Roswanira Abdul

    2015-10-01

    The chemical production of methyl oleate using chemically synthesized fatty acid alcohols and other toxic chemicals may lead to significant environmental hazards to mankind. Being a highly valuable fatty acid replacement raw material in oleochemical industry, the mass production of methyl oleate via environmentally favorable processes is of concern. In this context, an alternative technique utilizing Candida rugosa lipase (CRL) physically adsorbed on multi-walled carbon nanotubes (MWCNTs) has been suggested. In this study, the acid-functionalized MWCNTs prepared using a mixture of HNO3 and H2SO4 (1:3 v/v) was used as support for immobilizing CRL onto MWCNTs (CRL-MWCNTs) as biocatalysts. Enzymatic esterification was performed and the efficiency of CRL-MWCNTs was evaluated against the free CRL under varying conditions, viz. temperature, molar ratio of acid/alcohol, solvent log P, and enzyme loading. The CRL-MWCNTs resulted in 30-110 % improvement in the production of methyl oleate over the free CRL. The CRL-MWCNTs attained its highest yield (84.17 %) at 50 °C, molar ratio of acid/alcohol of 1:3, 3 mg/mL of enzyme loading, and iso-octane (log P 4.5) as solvent. Consequently, physical adsorption of CRL onto acid-functionalized MWCNTs has improved the activity and stability of CRL and hence provides an environmentally friendly means for the production of methyl oleate.

  10. DNA Methylation Perturbations in Genes Involved in Polyunsaturated Fatty Acid Biosynthesis Associated with Depression and Suicide Risk

    PubMed Central

    Haghighi, Fatemeh; Galfalvy, Hanga; Chen, Sean; Huang, Yung-yu; Cooper, Thomas B.; Burke, Ainsley K.; Oquendo, Maria A.; Mann, J. John; Sublette, M. Elizabeth

    2015-01-01

    Polyunsaturated fatty acid (PUFA) status has been associated with neuropsychiatric disorders, including depression and risk of suicide. Long-chain PUFAs (LC-PUFAs) are obtained in the diet or produced by sequential desaturation and elongation of shorter-chain precursor fatty acids linoleic acid (LA, 18:2n-6) and α-linolenic acid (ALA, 18:3n-3). We compared DNA methylation patterns in genes involved in LC-PUFA biosynthesis in major depressive disorder (MDD) with (n = 22) and without (n = 39) history of suicide attempt, and age- and sex-matched healthy volunteers (n = 59). Plasma levels of selected PUFAs along the LC-PUFA biosynthesis pathway were determined by transesterification and gas chromatography. CpG methylation levels for the main human LC-PUFA biosynthetic genes, fatty acid desaturases 1 (Fads1) and 2 (Fads2), and elongation of very long-chain fatty acids protein 5 (Elovl5), were assayed by bisulfite pyrosequencing. Associations between PUFA levels and diagnosis or suicide attempt status did not survive correction for multiple testing. However, MDD diagnosis and suicide attempts were significantly associated with DNA methylation in Elovl5 gene regulatory regions. Also the relative roles of PUFA levels and DNA methylation with respect to diagnostic and suicide attempt status were determined by least absolute shrinkage and selection operator logistic regression analyses. We found that PUFA associations with suicide attempt status were explained by effects of Elovl5 DNA methylation within the regulatory regions. The observed link between plasma PUFA levels, DNA methylation, and suicide risk may have implications for modulation of disease-associated epigenetic marks by nutritional intervention. PMID:25972837

  11. Conversion of beet molasses and cheese whey into fatty acid methyl esters by the yeast Cryptococcus curvatus.

    PubMed

    Takakuwa, Naoya; Saito, Katsuichi

    2010-01-01

    Eighty-one yeast isolates from raw milk were surveyed for the production of fatty acid methyl esters (FAME). Only one species, identified as Cryptococcus curvatus, produced FAME at a detectable level. Cr. curvatus TYC-19 produced more FAME from beet molasses and cheese whey medium than other strains of the same species. In both media, the major FAME produced were linoleic and oleic acid methyl esters. Sequence analysis of the internal transcribed spacer region of ribosomal DNA indicated that TYC-19 diverged from the same species.

  12. Photoinduced amino-imino tautomerization reaction in 2-aminopyrimidine and its methyl derivatives with acetic acid

    NASA Astrophysics Data System (ADS)

    Kitamura, Teruyoshi; Hikita, Atushi; Ishikawa, Hironori; Fujimoto, Akira

    2005-12-01

    The electronic absorption and fluorescence spectra of 2-aminopyrimidine (2APM), 2-amino-4-methylpyrimidine (2A4MPM), and 2-amino-4,6-dimethylpyrimidine (2ADMPM) with acetic acid (AcOH) were measured in isooctane (2,2,4-trimethylpentane) at room temperature. From the absorption spectra, a hydrogen-bonded complex formation of the 2APM/AcOH, 2A4MPM/AcOH, and 2ADMPM/AcOH systems was recognized in isooctane. The enthalpy changes (-Δ H) for the complex formation were estimated to be ca. 41.2-45.1 kJ mol -1 and increased in proportion to the numbers of the methyl group introduced into the 2APM. The -Δ H values refer to the formation of the hydrogen-bonded 1:1 complex between the ring nitrogen atom and NH 2 group of the aminopyrimidine and the OH and C dbnd O groups of AcOH, respectively. In the 2A4MPM/AcOH double hydrogen-bonded complex the OH group of AcOH is thought to be linked to the ring nitrogen at the 1-postion of 2A4MPM. The fluorescence spectral results indicate that the double proton transfer reaction takes place during the excited state, and gives rise to an imino-tautomer vibration emission, from analogy with the fluorescences of 1-methyl-2(1H)-pyrimidinimine (MPMI), 1,4-dimethyl-2(1H)-pyrimidinimine (DMPMI), and 1,4,6-trimethyl-2(1H)-pyrimidinimine (TMPMI). The fluorescence quantum yields of the imino-tautomers also increased in proportion to the numbers of the methyl group introduced into the 2APM.

  13. Simultaneous determination of salicylic, 3-methyl salicylic, 4-methyl salicylic, acetylsalicylic and benzoic acids in fruit, vegetables and derived beverages by SPME-LC-UV/DAD.

    PubMed

    Aresta, Antonella; Zambonin, Carlo

    2016-03-20

    Salicylic and benzoic acid are phenolic acids occurring in plant cells, thus they can be present in fruit and vegetables at various levels. They possess anti-inflammatory and antimicrobial properties, however they may induce symptoms and health problems in a small percentage of the population. Therefore, a low phenolic acid diet may be of clinical benefit to such individuals. In order to achieve this goal, the concentration of these substances in different food and beverages should be assessed. The present work describes for the first time a new method, based on solid phase microextraction (polydimethylsiloxane-divinylbenzene fiber) coupled to liquid chromatography with UV diode array detection, for the simultaneous determination of salicylic acid, 3-methyl salicylic acid, 4-methyl salicylic acid, acetylsalicylic acid and benzoic acid in selected fruit, vegetables and beverages. All the aspects influencing fiber adsorption (time, temperature, pH, salt addition) and desorption (desorption and injection time, desorption solvent mixture composition) of the analytes have been investigated. An isocratic separation was performed using an acetonitrile-phosphate buffer (pH 2.8; 2 mM) mixture (70:30, v/v) as the mobile phase. The estimated LOD and LOQ values (μg/mL) were in the range 0.002-0.028 and 0.007-0.095. The within-day and day-to-day precision values (RSD%) were between 4.7-6.1 and 6.6-9.4, respectively. The method has been successfully applied to the analysis of fava beans, blueberries, kiwi, tangerines, lemons, oranges and fruit juice (lemon and blueberry) samples. The major advantage of the method is that it only requires simple homogenization and/or centrifugation and dilution steps prior to SPME and injection in the LC system.

  14. Inhibition of the hyperpolarization-activated current (if) of rabbit SA node myocytes by niflumic acid.

    PubMed

    Accili, E A; DiFrancesco, D

    1996-03-01

    The effects of the amphiphilic substance niflumic acid (NFA) were examined in myocytes isolated from the sino-atrial node of the rabbit heart. NFA (50 and 500 microM), for 30-60 s, produced a reversible negative chronotropic effect by reducing the rate of diastolic depolarization, suggesting an inhibitory effect on the hyperpolarization-activated pacemaker current (if). NFA (from 0.05 to 500 microM) inhibited if by modifying the current kinetics, without alteration of the conductance. This was shown by evidence indicating that: (1) NFA inhibited if during hyperpolarizing pulses to the mid-point of if activation but not at fully activating voltages; (2) the slope and reversal potential of the fully activated current/voltage (I/V) relation were not altered by NFA, indicating no change in slope conductance or ion selectivity; and (3) hyperpolarizing ramp protocols confirmed the lack of action of 50 microM NFA on the fully activated current and a shift of approximately -8 mV. Although similar to inhibition by acetylcholine (ACh), inhibition by NFA was only partly additive with the action of ACh and was not altered by atropine or pertussis toxin, both of which eliminated the action of ACh. The effect of NFA was present after stimulation of adenylate cyclase by forskolin and after inhibition of phosphodiesterase by isobutylmethylxanthine (IBMX). In cell-attached patch measurements, NFA applied externally did not affect if measured in the patch. Finally, application of NFA to the cytoplasmic side of excised patches did not alter the current in the absence or presence of adenosine 3',5'-cyclic monophosphate (cAMP). These results suggest an external, membrane-delimited action of NFA on if.

  15. Polymer electrolyte membrane based on 2-acrylamido-2-methyl propanesulfonic acid fabricated by embedded polymerization

    NASA Astrophysics Data System (ADS)

    Pei, Haiqin; Hong, Liang; Lee, Jim Yang

    Methanol crossover through the Nafion membrane is a perennial problem in the operation of direct methanol fuel cells (DMFCs) and therefore justifies the search for a Nafion substitute. This study reports a new methanol-blocking polymer matrix which consists of a methanol barrier phase and an embedded proton source. A three-component polymer blend (TCPB) of poly(4-vinylphenol-co-methyl methacrylate), poly(butyl methacrylate) (PBMA), and Paraloid ® B-82 acrylic copolymer resins is used as a methanol barrier. In order to implant a proton source in the membrane as homogeneously as possible, the hydrophilic monomers, 2-acrylamido-2-methyl propanesulfonic acid (AMPS), 2-hydroxyethyl methacrylate (HEMA) and a cross-linking agent (poly(ethylene glycol) dimethylacrylate) (PEGDMA) are polymerized after they have been embedded in the TCPB matrix. The embedded polymerization has resulted in an asymmetric membrane structure, in which the hydrophilic network is sandwiched by two outer layers of predominantly hydrophobic TCPB. Measurements are made of properties of the AMPS-containing membranes that are important to fuel cell applications such as water uptake, ion-exchange capacity, proton conductivity, methanol permeability and tensile strength. The highest proton conductivity of the AMPS-containing membrane is about 0.030 S cm -1 at 70 °C. The low methanol permeability (10 -8 to 10 -7 cm 2 s -1) of the AMPS-containing membranes is their primary advantage for DMFC applications.

  16. Alkali metal ion binding to amino acids versus their methyl esters: affinity trends and structural changes in the gas phase.

    PubMed

    Talley, Jody M; Cerda, Blas A; Ohanessian, Gilles; Wesdemiotis, Chrys

    2002-03-15

    The relative alkali metal ion (M(+)) affinities (binding energies) between seventeen different amino acids (AA) and the corresponding methyl esters (AAOMe) were determined in the gas phase by the kinetic method based on the dissociation of AA-M(+)-AAOMe heterodimers (M=Li, Na, K, Cs). With the exception of proline, the Li(+), Na(+), and K(+) affinities of the other aliphatic amino acids increase in the order AAacids, which are particularly basic molecules, the order AA>AAOMe is already observed for K(+). Proline binds more strongly than its methyl ester to all M(+) except Li(+). Ab initio calculations on the M(+) complexes of alanine, beta-aminoisobutyric acid, proline, glycine methyl ester, alanine methyl ester, and proline methyl ester show that their energetically most favorable complexes result from charge solvation, except for proline which forms salt bridges. The most stable mode of charge solvation depends on the ligand (AA or AAOMe) and, for AA, it gradually changes with metal ion size. Esters chelate all M(+) ions through the amine and carbonyl groups. Amino acids coordinate Li(+) and Na(+) ions through the amine and carbonyl groups as well, but K(+) and Cs(+) ions are coordinated by the O atoms of the carboxyl group. Upon consideration of these differences in favored binding geometries, the theoretically derived relative M(+) affinities between aliphatic AA and AAOMe are in good overall agreement with the above given experimental trends. The majority of side chain functionalized amino acids studied show experimentally the affinity order AAacids lysine and arginine, whose K(+) (for arginine) and Cs(+) complexes (for both) follow the affinity order AA>AAOMe. The latter ranking is attributed to salt bridge formation.

  17. Interaction between methyl glyoxal and ascorbic acid: experimental and theoretical aspects

    NASA Astrophysics Data System (ADS)

    Banerjee, D.; Koll, A.; Filarowski, A.; Bhattacharyya, S. P.; Mukherjee, S.

    2004-06-01

    The absorption spectral change of methyl glyoxal (MG) due to the interaction with ascorbic acid (AA or Vitamin C) has been investigated using steady-state spectroscopic technique. A plausible explanation for the spectral change has been discussed on the basis of hydrogen bonding interaction between the two interacting species. The equilibrium constant for the complex formation due to hydrogen bonding interaction between MG and AA has been obtained from absorption spectral changes. Ab inito calculations with DFT B3LYP/6/31G (d,p) basis sets have been used to find out the molecular structure of the hydrogen bonded complex. The O⋯H distance found in the OH⋯O hydrogen bond turns out to be quite short (1.974 Å) which is in conformity with the large value of the equilibrium constant determined experimentally.

  18. Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.

    PubMed

    Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

    2005-02-01

    The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems.

  19. Determination of monomethylarsonous acid, a key arsenic methylation intermediate, in human urine.

    PubMed Central

    Le, X C; Ma, M; Cullen, W R; Aposhian, H V; Lu, X; Zheng, B

    2000-01-01

    In this study we report on the finding of monomethylarsonous acid [MMA(III)] in human urine. This newly identified arsenic species is a key intermediate in the metabolic pathway of arsenic biomethylation, which involves stepwise reduction of pentavalent to trivalent arsenic species followed by oxidative addition of a methyl group. Arsenic speciation was carried out using ion-pair chromatographic separation of arsenic compounds with hydride generation atomic fluorescence spectrometry detection. Speciation of the inorganic arsenite [As(III)], inorganic arsenate [As(V)], monomethylarsonic acid [MMA(V)], dimethylarsinic acid [DMA(V)], and MMA(III) in a urine sample was complete in 5 min. Urine samples collected from humans before and after a single oral administration of 300 mg sodium 2,3-dimercapto-1-propane sulfonate (DMPS) were analyzed for arsenic species. MMA(III) was found in 51 out of 123 urine samples collected from 41 people in inner Mongolia 0-6 hr after the administration of DMPS. MMA(III )in urine samples did not arise from the reduction of MMA(V) by DMPS. DMPS probably assisted the release of MMA(III) that was formed in the body. Along with the presence of MMA(III), there was an increase in the relative concentration of MMA(V) and a decrease in DMA(V) in the urine samples collected after the DMPS ingestion. PMID:11102289

  20. Metabolomics Analysis and Biosynthesis of Rosmarinic Acid in Agastache rugosa Kuntze Treated with Methyl Jasmonate

    PubMed Central

    Uddin, Md. Romij; Xu, Hui; Park, Woo Tae; Tuan, Pham Anh; Li, Xiaohua; Chung, Eunsook; Lee, Jai-Heon; Park, Sang Un

    2013-01-01

    This study investigated the effect of methyl jasmonate (MeJA) on metabolic profiles and rosmarinic acid (RA) biosynthesis in cell cultures of Agastache rugosa Kuntze. Transcript levels of phenylpropanoid biosynthetic genes, i.e., ArPAL, Ar4CL, and ArC4H, maximally increased 4.5-fold, 3.4-fold, and 3.5-fold, respectively, compared with the untreated controls, and the culture contained relatively high amounts of RA after exposure of cells to 50 µM MeJA. RA levels were 2.1-, 4.7-, and 3.9-fold higher after exposure to 10, 50, and 100 µM MeJA, respectively, than those in untreated controls. In addition, the transcript levels of genes attained maximum levels at different time points after the initial exposure. The transcript levels of ArC4H and Ar4CL were transiently induced by MeJA, and reached a maximum of up to 8-fold at 3 hr and 6 hr, respectively. The relationships between primary metabolites and phenolic acids in cell cultures of A. rugosa treated with MeJA were analyzed by gas chromatography coupled with time-of-flight mass spectrometry. In total, 45 metabolites, including 41 primary metabolites and 4 phenolic acids, were identified from A. rugosa. Metabolite profiles were subjected to partial least square-discriminate analysis to evaluate the effects of MeJA. The results indicate that both phenolic acids and precursors for the phenylpropanoid biosynthetic pathway, such as aromatic amino acids and shikimate, were induced as a response to MeJA treatment. Therefore, MeJA appears to have an important impact on RA accumulation, and the increased RA accumulation in the treated cells might be due to activation of the phenylpropanoid genes ArPAL, ArC4H, and Ar4CL. PMID:23724034

  1. Priming of seeds with methyl jasmonate induced resistance to hemi-biotroph Fusarium oxysporum f.sp. lycopersici in tomato via 12-oxo-phytodienoic acid, salicylic acid, and flavonol accumulation.

    PubMed

    Król, P; Igielski, R; Pollmann, S; Kępczyńska, E

    2015-05-01

    Methyl jasmonate (MeJA) was tested by seed treatment for its ability to protect tomato seedlings against fusarium wilt caused by the soil-borne fungal pathogen Fusarium oxysporum f.sp. lycopersici. Isolated from Solanum lycopersicon L. seeds, cv. Beta fungus was identified as F. oxysporum f.sp. lycopersici Race 3 fungus by using phytopathological and molecular methods. MeJA applied at 0.01, 0.1 and 1 mM reduced spore germination and mycelial growth in vitro. Soaking of tomato seeds in MeJA solution at 0.1 mM for 1 h significantly enhanced the resistance level against the tested fungus in tomato seedlings 4 weeks after inoculation. The extracts from leaves of 15-day-old seedlings obtained from previously MeJA soaked seeds had the ability to inhibit in vitro spore germination of tested fungus. In these seedlings a significant increase in the levels phenolic compounds such as salicylic acid (SA), kaempferol and quercetin was observed. Up-regulation of phenylalanine ammonia-lyase (PAL5) and benzoic acid/salicylic acid carboxyl methyltransferase (BSMT) genes and down-regulation of the isochorysmate synthase (ICS) gene in response to exogenous MeJA application indicate that the phenylalanine ammonia-lyase (PAL), not the isochorismate (IC) pathway, is the primary route for SA production in tomato. Moreover, the increased accumulation of the flavonols quercetin and kaempferol appears closely related to the increase of PAL5, chalcone synthase (CHS) and flavonol synthase/flavanone 3-hydroxylase-like (FLS) genes. Elevated levels of salicylic acid in seedlings raised from MeJA-soaked seeds were simultaneously accompanied by a decrease of jasmonic acid, the precursor of MeJA, and an increase of 12-oxo-phytodienoic acid (OPDA), the precursor of jasmonic acid. The present results indicate that the priming of tomato seeds with 0.1mM MeJA before sowing enables the seedlings grown from these seeds to reduce the attack of the soil-borne fungal pathogen F. oxysporum f.sp. lycopersici

  2. Improvement of holographic thermal stability in phenanthrenequinone-doped poly(methyl methacrylate-co-methacrylic acid) photopolymer

    NASA Astrophysics Data System (ADS)

    Yu, Dan; Liu, Hongpeng; Wang, Heng; Wang, Jian; Jiang, Yongyuan; Sun, Xiudong

    2011-08-01

    Experimental studies of holographic thermal stability in phenanthrenequinone (PQ)-doped poly(methyl methacrylate-co-methacrylic acid) [P(MMA-co-MAA)] photopolymers are presented. A possibility to improve the thermal stability of holograms is demonstrated by doping methacrylic acid (MAA) into the poly(methyl methacrylate) (PMMA) polymer matrix. MAA as a copolymerization monomer can form a more stable polymer matrix with methyl methacrylate (MMA) monomer and increase average molecular weight of photoproducts, which finally depress the diffusion of photoproduct. The optimized MAA concentration copolymerized into P(MMA-co-MAA) polymer matrix can bring nearly a month's lifetime of gratings, which is obviously an improvement over the usual PQ-PMMA material under thermal treatment.

  3. Soybean biodiesel methyl esters, free glycerin and acid number quantification by 1H nuclear magnetic resonance spectroscopy.

    PubMed

    Coral, Natasha; Rodrigues, Elizabeth; Rumjanek, Victor; Zamian, José Roberto; da Rocha Filho, Geraldo Narciso; da Costa, Carlos Emmerson Ferreira

    2013-02-01

    Production of alternative fuels, such as biodiesel, from transesterification of vegetable oil driven by heterogeneous catalysts is a promising alternative to fossil diesel. However, achieving a successful substitution for a new renewable fuel depends on several quality parameters. (1)H NMR spectroscopy was used to determine the amount of methyl esters, free glycerin and acid number in the transesterification of soybean oil with methanol in the presence of hydrotalcite-type catalyst to produce biodiesel. Reaction parameters, such as temperature and time, were used to evaluate soybean oil methyl esters rate conversion. Temperatures of 100 to 180 °C and times of 20 to 240 min were tested on a 1 : 12 molar ratio soybean oil/methanol reaction. At 180 °C/240 min conditions, a rate of 94.5 wt% of methyl esters was obtained, where free glycerin and free fatty acids were not detected.

  4. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.8450 2-Propenoic acid, 2-methyl-, 2- ethyl ester. (a) Chemical substance... acid, 2-methyl-, 2- ethyl ester, (PMN P-90-333) is subject to reporting under this section for...

  5. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.8450 2-Propenoic acid, 2-methyl-, 2- ethyl ester. (a) Chemical substance... acid, 2-methyl-, 2- ethyl ester, (PMN P-90-333) is subject to reporting under this section for...

  6. Metabolism of phytanic acid and 3-methyl-adipic acid excretion in patients with adult Refsum disease.

    PubMed

    Wierzbicki, Anthony S; Mayne, Phillip D; Lloyd, Matthew D; Burston, David; Mei, Guam; Sidey, Margaret C; Feher, Michael D; Gibberd, F Brian

    2003-08-01

    Adult Refsum disease (ARD) is associated with defective alpha-oxidation of phytanic acid (PA). omega-Oxidation of PA to 3-methyl-adipic acid (3-MAA) occurs although its clinical significance is unclear. In a 40 day study of a new ARD patient, where the plasma half-life of PA was 22.4 days, omega-oxidation accounted for 30% initially and later all PA excretion. Plasma and adipose tissue PA and 3-MAA excretion were measured in a cross-sectional study of 11 patients. The capacity of the omega-oxidation pathway was 6.9 (2.8-19.4) mg [20.4 (8.3-57.4) micromol] PA/day. 3-MAA excretion correlated with plasma PA levels (r = 0.61; P = 0.03) but not adipose tissue PA content. omega-Oxidation during a 56 h fast was studied in five patients. 3-MAA excretion increased by 208 +/- 58% in parallel with the 158 (125-603)% rise in plasma PA. Plasma PA doubled every 29 h, while 3-MAA excretion followed second-order kinetics. Acute sequelae of ARD were noted in three patients (60%) after fasting. The omega-oxidation pathway can metabolise PA ingested by patients with ARD, but this activity is dependent on plasma PA concentration. omega-Oxidation forms a functional reserve capacity that enables patients with ARD undergoing acute stress to cope with limited increases in plasma PA levels.

  7. 21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... contain not less than 35 percent of other fatty acid esters composed of oleic acid, palmitic acid, stearic... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic acids). 573.637 Section 573.637 Food and Drugs FOOD...

  8. 40 CFR 721.4792 - 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-isoalkyl esters, C13-rich. 721.4792 Section 721.4792 Protection of Environment ENVIRONMENTAL PROTECTION... esters, C13-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich (PMN P-99-1189; CAS...

  9. 40 CFR 721.8500 - 2-Propenoic acid, 2-methyl-, 7-oxabicyclo [4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-oxabicyclo hept-3-ylmethyl ester. 721.8500 Section 721.8500 Protection of Environment ENVIRONMENTAL... hept-3-ylmethyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance 2-propenoic acid, 2-methyl-, 7-oxabicyclo hept-3-ylmethyl ester (PMN P-89-30) is...

  10. 40 CFR 721.4792 - 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-isoalkyl esters, C13-rich. 721.4792 Section 721.4792 Protection of Environment ENVIRONMENTAL PROTECTION... esters, C13-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich (PMN P-99-1189; CAS...

  11. 40 CFR 721.8500 - 2-Propenoic acid, 2-methyl-, 7-oxabicyclo [4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-oxabicyclo hept-3-ylmethyl ester. 721.8500 Section 721.8500 Protection of Environment ENVIRONMENTAL... hept-3-ylmethyl ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance 2-propenoic acid, 2-methyl-, 7-oxabicyclo hept-3-ylmethyl ester (PMN P-89-30) is...

  12. Evaluation of peanut fatty acid methyl ester sprays, combustion, and emissions, for use in an indirect injection diesel engine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The paper provides an analysis of 100% peanut fatty acid methyl esters (FAMEs) and peanut FAME/ULSD#2 blends (P20, P35, and P50) in an indirect injection (IDI) diesel engine (for auxiliary power unit applications) in comparison to ultralow sulfur diesel no. 2 (ULSD#2) at various speeds and 100% load...

  13. Structure-function properties of amylose-oleic acid inclusion complexes grafted with poly(methyl acrylate)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spherulites, produced by steam jet-cooking high-amylose starch and oleic acid, were grafted with methyl acrylate, both before and after removal of un-complexed amylopectin. For comparison, granular high-amylose corn starch was graft polymerized in a similar manner. The amount of grafted and ungrafte...

  14. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4..., reaction products with 4,4′ -methylenebis (cyclohexanamine) (PMN P-10-47) is subject to reporting...

  15. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4..., reaction products with 4,4′ -methylenebis (cyclohexanamine) (PMN P-10-47) is subject to reporting...

  16. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4..., reaction products with 4,4′ -methylenebis (cyclohexanamine) (PMN P-10-47) is subject to reporting...

  17. Properties of amylose-oleic acid inclusion complexes from corn starch grafted with poly(methyl acrylate)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn starch granules have been previously investigated as fillers in polymers. In this study, much smaller particles in the form of spherulites produced by steam jet-cooking high-amylose corn starch and oleic acid to form amylose inclusion complexes were graft polymerized with methyl acrylate, both ...

  18. Preparation of fatty acid methyl esters from hazelnut, high-oleic peanut and walnut oils and evaluation as biodiesel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hazelnut, walnut and high-oleic peanut oils were converted into fatty acid methyl esters using catalytic sodium methoxide and evaluated as potential biodiesel fuels. These feedstocks were of interest due to their adaptability to marginal lands and their lipid production potentials (780-1780 L ha-1 y...

  19. Determination of Total Lipids as Fatty Acid Methyl Esters (FAME) by in situ Transesterification: Laboratory Analytical Procedure (LAP)

    SciTech Connect

    Van Wychen, S.; Laurens, L. M. L.

    2013-12-01

    This procedure is based on a whole biomass transesterification of lipids to fatty acid methyl esters to represent an accurate reflection of the potential of microalgal biofuels. Lipids are present in many forms and play various roles within an algal cell, from cell membrane phospholipids to energy stored as triacylglycerols.

  20. Fatty acid synthase methylation levels in adipose tissue: effects of an obesogenic diet and phenolic compounds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA methylation is an epigenetic mechanism that can inhibit gene transcription. The aim of this study was to assess changes induced by an obesogenic diet in the methylation profile of genes involved in adipose tissue triacylglycerol metabolism, and to determine whether this methylation pattern can b...

  1. Changes in SCD gene DNA methylation after bariatric surgery in morbidly obese patients are associated with free fatty acids

    PubMed Central

    Morcillo, Sonsoles; Martín-Núñez, Gracia Mª; García-Serrano, Sara; Gutierrez-Repiso, Carolina; Rodriguez-Pacheco, Francisca; Valdes, Sergio; Gonzalo, Montserrat; Rojo-Martinez, Gemma; Moreno-Ruiz, Francisco J.; Rodriguez-Cañete, Alberto; Tinahones, Francisco; García-Fuentes, Eduardo

    2017-01-01

    Stearoyl CoA Desaturase-1 (SCD) is considered as playing an important role in the explanation of obesity. The aim of this study was to evaluate whether the DNA methylation SCD gene promoter is associated with the metabolic improvement in morbidly obese patients after bariatric surgery. The study included 120 subjects with morbid obesity who underwent a laparoscopic Roux-en Y gastric by-pass (RYGB) and a control group of 30 obese subjects with a similar body mass index (BMI) to that found in morbidly obese subjects six months after RYGB. Fasting blood samples were obtained before and at six months after RYGB. DNA methylation was measured by pyrosequencing technology. DNA methylation levels of the SCD gene promoter were lower in morbidly obese subjects before bariatric surgery but increased after RYGB to levels similar to those found in the control group. Changes of DNA methylation SCD gene were associated with the changes of free fatty acids levels (r = −0.442, p = 0.006) and HOMA-IR (r = −0.249, p = 0.035) after surgery. RYGB produces an increase in the low SCD methylation promoter levels found in morbidly obese subjects. This change of SCD methylation levels is associated with changes in FFA and HOMA-IR. PMID:28393901

  2. Nanoconjugate Platforms Development Based in Poly(β,L-Malic Acid) Methyl Esters for Tumor Drug Delivery

    PubMed Central

    Portilla-Arias, José; Patil, Rameshwar; Hu, Jinwei; Ding, Hui; Black, Keith L.; García-Alvarez, Montserrat; Muñoz-Guerra, Sebastián; Ljubimova, Julia Y.; Holler, Eggehard

    2010-01-01

    New copolyesters derived from poly(β,L-malic acid) have been designed to serve as nanoconjugate platforms in drug delivery. 25% and 50% methylated derivatives (coPMLA-Me25H75 and coPMLA-Me50H50) with absolute molecular weights of 32 600 Da and 33 100 Da, hydrodynamic diameters of 3.0 nm and 5.2 nm and zeta potential of −15mV and −8.25mV, respectively, were found to destabilize membranes of liposomes at pH 5.0 and pH 7.5 at concentrations above 0.05mg/mL. The copolymers were soluble in PBS (half life of 40 hours) and in human plasma (half life of 15 hours) but they showed tendency to aggregate at high levels of methylation. Fluorescence-labeled copolymers were internalized into MDA-MB-231 breast cancer cells with increased efficiency for the higher methylated copolymer. Viability of cultured brain and breast cancer cell lines indicated moderate toxicity that increased with methylation. The conclusion of the present work is that partially methylated poly(β,L-malic acid) copolyesters are suitable as nanoconjugate platforms for drug delivery. PMID:23024655

  3. Salicylic acid and jasmonic acid are essential for systemic resistance against tobacco mosaic virus in Nicotiana benthamiana.

    PubMed

    Zhu, Feng; Xi, De-Hui; Yuan, Shu; Xu, Fei; Zhang, Da-Wei; Lin, Hong-Hui

    2014-06-01

    Systemic resistance is induced by pathogens and confers protection against a broad range of pathogens. Recent studies have indicated that salicylic acid (SA) derivative methyl salicylate (MeSA) serves as a long-distance phloem-mobile systemic resistance signal in tobacco, Arabidopsis, and potato. However, other experiments indicate that jasmonic acid (JA) is a critical mobile signal. Here, we present evidence suggesting both MeSA and methyl jasmonate (MeJA) are essential for systemic resistance against Tobacco mosaic virus (TMV), possibly acting as the initiating signals for systemic resistance. Foliar application of JA followed by SA triggered the strongest systemic resistance against TMV. Furthermore, we use a virus-induced gene-silencing-based genetics approach to investigate the function of JA and SA biosynthesis or signaling genes in systemic response against TMV infection. Silencing of SA or JA biosynthetic and signaling genes in Nicotiana benthamiana plants increased susceptibility to TMV. Genetic experiments also proved the irreplaceable roles of MeSA and MeJA in systemic resistance response. Systemic resistance was compromised when SA methyl transferase or JA carboxyl methyltransferase, which are required for MeSA and MeJA formation, respectively, were silenced. Moreover, high-performance liquid chromatography-mass spectrometry analysis indicated that JA and MeJA accumulated in phloem exudates of leaves at early stages and SA and MeSA accumulated at later stages, after TMV infection. Our data also indicated that JA and MeJA could regulate MeSA and SA production. Taken together, our results demonstrate that (Me)JA and (Me)SA are required for systemic resistance response against TMV.

  4. 4-Hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester derivatives as potent anti-tumor agents.

    PubMed

    Hayakawa, Ichiro; Shioya, Rieko; Agatsuma, Toshinori; Furukawa, Hidehiko; Naruto, Shunji; Sugano, Yuichi

    2004-01-19

    Based on the structure of 4-hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester (1), which exhibits selective cytotoxicity against a tumorigenic cell line, (2,4-dimethoxyphenyl)-(4-hydroxy-3-methyl-6-phenylbenzofuran-2-yl)-methanone (18m) was designed and synthesized as a biologically stable derivative containing no ester group. Although the potency of 18m was almost the same as our initial hit compound 1, 18m is expected to last longer in the human body as an anticancer agent.

  5. A simple sonochemical method for fabricating poly(methyl methacrylate)/stearic acid phase change energy storage nanocapsules.

    PubMed

    Wang, Guxia; Xu, Weibing; Hou, Qian; Guo, Shengwei

    2015-11-01

    In this study, stearic acid suitable for thermal energy storage applications was nanoencapsulated in a poly(methyl methacrylate) shell. The nanocapsules were prepared using a simple ultrasonically initiated in situ polymerization method. The morphology and particle size of the poly(methyl methacrylate)/stearic acid phase change energy storage nanocapsules (PMS-PCESNs) were analyzed using transmission electron microscopy, scanning electron microscopy, atomic force microscopy and dynamic light scattering. The latent heat storage capacities of stearic acid and the PMS-PCESNs were determined using differential scanning calorimetry. The chemical composition of the nanocapsules was characterized using Fourier transform infrared spectroscopy. All of the results show that the PMS-PCESNs were synthesized successfully and that the latent heat storage capacity and encapsulation efficiency were 155.6 J/g and 83.0%, respectively, and the diameter of each nanocapsule was 80-90 nm.

  6. Photodynamic inactivation of Klebsiella pneumoniae biofilms and planktonic cells by 5-aminolevulinic acid and 5-aminolevulinic acid methyl ester.

    PubMed

    Liu, Chengcheng; Zhou, Yingli; Wang, Li; Han, Lei; Lei, Jin'e; Ishaq, Hafiz Muhammad; Nair, Sean P; Xu, Jiru

    2016-04-01

    The treatment of Klebsiella pneumoniae, particularly extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae, is currently a great challenge. Photodynamic antimicrobial chemotherapy is a promising approach for killing antibiotic-resistant bacteria. The aim of this study was to evaluate the capacity of 5-aminolevulinic acid (5-ALA) and its derivative 5-ALA methyl ester (MAL) in the presence of white light to cause photodynamic inactivation (PDI) of K. pneumoniae planktonic and biofilm cells. In the presence of white light, 5-ALA and MAL inactivated planktonic cells in a concentration-dependent manner. Biofilms were also sensitive to 5-ALA and MAL-mediated PDI. The mechanisms by which 5-ALA and MAL caused PDI of ESBL-producing K. pneumonia were also investigated. Exposure of K. pneumonia to light in the presence of either 5-ALA or MAL induced cleavage of genomic DNA and the rapid release of intracellular biopolymers. Intensely denatured cytoplasmic contents and aggregated ribosomes were also detected by transmission electron microscopy. Scanning electron microscopy showed that PDI of biofilms caused aggregated bacteria to detach and that the bacterial cell envelope was damaged. This study provides insights into 5-ALA and MAL-mediated PDI of ESBL-producing K. pneumoniae.

  7. Involvement of aberrant DNA methylation on reduced expression of lysophosphatidic acid receptor-1 gene in rat tumor cell lines

    SciTech Connect

    Tsujiuchi, Toshifumi . E-mail: ttujiuch@life.kindai.ac.jp; Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Fujii, Hiromasa; Mori, Toshio; Honoki, Kanya; Fukushima, Nobuyuki

    2006-10-27

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, it has been reported that alterations of LPA receptor expression might be important in the malignant transformation of tumor cells. Therefore, to assess an involvement of DNA methylation in reduced expression of the LPA receptor-1 (lpa1) gene, we investigated the expression of the lpa1 gene and its DNA methylation patterns in rat tumor cell lines. Both rat brain-derived neuroblastoma B103 and liver-derived hepatoma RH7777 cells used in this study indicated no expression of lpa1. For the analysis of methylation status, bisulfite sequencing was performed with B103 and RH7777 cells, comparing with other lpa1 expressed cells and normal tissues of brain and liver. The lpa1 expressed cells and tissues were all unmethylated in this region of lpa1. In contrast, both B103 and RH7777 cells were highly methylated, correlating with reduced expression of the lpa1. Treatment with 5-aza 2'-deoxycytidine induced expression of lpa1 gene in B103 and RH7777 cells after 24 h. In RH7777 cells treated with 5-aza 2'-deoxycytidine, stress fiber formation was also observed in response to LPA in RH7777 cells, but not in untreated RH7777 cells. These results suggest that aberrant DNA methylation of the lpa1 gene may be involved in its reduced expression in rat tumor cells.

  8. Chromatin and DNA methylation dynamics during retinoic acid-induced RET gene transcriptional activation in neuroblastoma cells

    PubMed Central

    Angrisano, T.; Sacchetti, S.; Natale, F.; Cerrato, A.; Pero, R.; Keller, S.; Peluso, S.; Perillo, B.; Avvedimento, V. E.; Fusco, A.; Bruni, C. B.; Lembo, F.; Santoro, M.; Chiariotti, L.

    2011-01-01

    Although it is well known that RET gene is strongly activated by retinoic acid (RA) in neuroblastoma cells, the mechanisms underlying such activation are still poorly understood. Here we show that a complex series of molecular events, that include modifications of both chromatin and DNA methylation state, accompany RA-mediated RET activation. Our results indicate that the primary epigenetic determinants of RA-induced RET activation differ between enhancer and promoter regions. At promoter region, the main mark of RET activation was the increase of H3K4me3 levels while no significant changes of the methylation state of H3K27 and H3K9 were observed. At RET enhancer region a bipartite chromatin domain was detected in unstimulated cells and a prompt demethylation of H3K27me3 marked RET gene activation upon RA exposure. Moreover, ChIP experiments demonstrated that EZH2 and MeCP2 repressor complexes were associated to the heavily methylated enhancer region in the absence of RA while both complexes were displaced during RA stimulation. Finally, our data show that a demethylation of a specific CpG site at the enhancer region could favor the displacement of MeCP2 from the heavily methylated RET enhancer region providing a novel potential mechanism for transcriptional regulation of methylated RA-regulated loci. PMID:20952403

  9. Esterification of oil adsorbed on palm decanter cake into methyl ester using sulfonated rice husk ash as heterogeneous acid catalyst

    NASA Astrophysics Data System (ADS)

    Hindryawati, Noor; Erwin, Maniam, Gaanty Pragas

    2017-02-01

    Palm Decanter cake (PDC) which is categorized as the waste from palm oil mill has been found to contain residual crude palm oil. The oil adsorbed on the PDC (PDC-oil) can be extracted and potentially used as feedstock for biodiesel production. Feedstock from waste like PDC-oil is burdened with high free fatty acids (FFAs) which make the feedstock difficult to be converted into biodiesel using basic catalyst. Therefore, in this study, a solid acid, RHA-SO3H catalyst was synthesized by sulfonating rice husk ash (RHA) with concentrated sulfuric acid. The RHA-SO3H prepared was characterized with TGA, FTIR, BET, XRD, FE-SEM, and Hammett indicators (methyl red, bromophenol blue, and crystal violet). PDC was found to have about 11.3 wt. % oil recovered after 1 hour extraction using ultrasound method. The presence of sulfonate group was observed in IR spectrum, and the surface area of RHA-SO3H was reduced to 37 m2.g-1 after impregnation of sulfonate group. The RHA-SO3H catalyst showed that it can work for both esterification of free fatty acid which is present in PDC-oil, and transesterification of triglycerides into methyl ester. The results showed highest methyl ester content of 70.2 wt.% at optimal conditions, which was 6 wt.% catalyst amount, methanol to oil molar ratio of 17:1 for 5 hours at 120 °C.

  10. Electron Affinity of Phenyl-C61-Butyric Acid Methyl Ester (PCBM)

    SciTech Connect

    Larson, Bryon W.; Whitaker, James B.; Wang, Xue B.; Popov, Alexey A.; Rumbles, Garry; Kopidakis, Nikos; Strauss, Steven H.; Boltalina, Olga V.

    2013-07-25

    The gas-phase electron affinity (EA) of phenyl-C61-butyric acid methyl ester (PCBM), one of the best-performing electron acceptors in organic photovoltaic devices, is measured by lowtemperature photoelectron spectroscopy for the first time. The obtained value of 2.63(1) eV is only ca. 0.05 eV lower than that of C60 (2.68(1) eV), compared to a 0.09 V difference in their E1/2 values measured in this work by cyclic voltammetry. Literature E(LUMO) values for PCBM that are typically estimated from cyclic voltammetry, and commonly used as a quantitative measure of acceptor properties, are dispersed over a wide range between -4.3 and -3.62 eV; the reasons for such a huge discrepancy are analyzed here, and the protocol for reliable and consistent estimations of relative fullerene-based acceptor strength in solution is proposed.

  11. Modification of N-Methyl-N-Nitrosourea initiated bladder carcinogenesis in Wistar rats by terephthalic acid

    SciTech Connect

    Cui Lunbiao; Shi Yuan; Dai Guidong; Pan Hongxin; Chen Jianfeng; Song Ling; Wang Shouling; Chang, Hebron C.; Sheng Hongbing; Wang Xinru . E-mail: xrwang@njmu.edu.cn

    2006-01-15

    The effect of terephthalic acid (TPA) on urinary bladder carcinogenesis was examined. Male Wistar rats were initiated by injection of N-Methyl-N-Nitrosourea (MNU) (20 mg/kg b.w. ip) twice a week for 4 weeks, then given basal diet containing 5% TPA, 5% TPA plus 4% Sodium bicarbonate (NaHCO{sub 3}) or 1% TPA for the next 22 weeks, and then euthanized. 5% TPA treatment induced a high incidence of urinary bladder calculi and a large amount of precipitate. Though 5% TPA plus 4% Sodium bicarbonate (NaHCO{sub 3}) and 1% TPA treatment did not induce urinary bladder calculi formation, they resulted in a moderate increase in urinary precipitate. Histological examination of urinary bladder revealed that MNU-5% TPA treatment resulted in a higher incidence of simple hyperplasia, papillary or nodular hyperplasia (PN hyperplasia), papilloma and cancer than MNU control. MNU-5% TPA plus 4% Sodium bicarbonate (NaHCO{sub 3}) and 1% TPA treatment increased slightly the incidence of simple hyperplasia and PN hyperplasia (not statistically significant). The major elements of the precipitate are phosphorus, potassium, sulfur, chloride, calcium and TPA. The present study indicated that the calculi induced by TPA had a strong promoting activity on urinary bladder carcinogenesis and the precipitate containing calcium terephthalate (CaTPA) may also have weak promoting activity on urinary bladder carcinogenesis.

  12. Modified hydroxypropyl methyl cellulose: Efficient matrix for controlled release of 5-amino salicylic acid.

    PubMed

    Das, Raghunath; Pal, Sagar

    2015-01-01

    Hydroxypropyl methyl cellulose has been modified by grafting synthetic polyacrylamide chains [g-HPMC (M)] in presence of microwave irradiation, which has used as carrier for controlled release of 5-amino salicylic acid (5-ASA). The FTIR and UV-vis-NIR studies reveal the excellent compatibility between g-HPMC (M) and 5-ASA. Field emission scanning electron microscopy (FESEM) and UV-vis-NIR analyses suggest that physical interaction predominates between the drug and matrix. % equilibrium swelling ratio (% ESR) of g-HPMC (M) decreased with addition of salt solutions and follow the order: Na(+)>K(+)>Mg(2+)>Ca(2+)>Al(3+). The in vitro 5-ASA release studies indicate that g-HPMC (M) delivers the drug preferentially in colonic region in more sustained way than that of HPMC. The 5-ASA release follows first order kinetics and non-Fickian diffusion mechanism. These favorable features make the graft copolymer a potential matrix for colon specific delivery of 5-ASA.

  13. Hydroxypropyl methyl cellulose grafted with polyacrylamide: application in controlled release of 5-amino salicylic acid.

    PubMed

    Das, Raghunath; Pal, Sagar

    2013-10-01

    In the present study, hydroxypropyl methyl cellulose grafted with polyacrylamide (HPMC-g-PAM) hydrogel was evaluated in vitro as a potential carrier for controlled release of 5-amino salicylic acid (5-ASA). The graft copolymer was developed by grafting PAM chains onto HPMC backbone using potassium persulphate as initiator. The swelling behaviour of hydrogel based tablet was investigated as a function of pH and time in various buffer solutions similar to that of gastric and intestinal fluids. The % equilibrium swelling was found to be higher in case of simulated intestinal fluid (pH=7.4) and lower in simulated gastric fluid (pH=1.2), making an ideal matrix as required for colon specific drug delivery. The drug release study was performed at various pH values akin to the condition of GI tract. The release kinetics of 5-ASA showed non-Fickian diffusion behaviour. This indicates that the release is controlled by a combination of polymer relaxation or erosion of the matrix and diffusion of the drug from the swollen matrix.

  14. Thiol-based Redox Proteins in Brassica napus Guard Cell Abscisic Acid and Methyl Jasmonate Signaling

    PubMed Central

    Zhu, Mengmeng; Zhu, Ning; Song, Wen-yuan; Harmon, Alice C.; Assmann, Sarah M.; Chen, Sixue

    2014-01-01

    SUMMARY Reversibly oxidized cysteine sulfhydryl groups serve as redox sensors or targets of redox sensing that are important in different physiological processes. Little is known, however, about redox sensitive proteins in guard cells and how they function in stomatal signaling. In this study, Brassica napus guard cell proteins altered by redox in response to abscisic acid (ABA) or methyl jasmonate (MeJA) were identified by complementary proteomics approaches, saturation differential in-gel electrophoresis (DIGE) and isotope-coded affinity tag (ICAT). In total, 65 and 118 potential redox responsive proteins were identified in ABA and MeJA treated guard cells, respectively. All the proteins contain at least one cysteine, and over half of them are predicted to form intra-molecular disulfide bonds. Most of the proteins fall into the functional groups of energy, stress and defense, and metabolism. Based on the peptide sequences identified by mass spectrometry, 30 proteins were common to ABA and MeJA treated samples. A total of 44 cysteines was mapped in all the identified proteins, and their levels of redox sensitivity were quantified. Two of the proteins, a SNRK2 kinase and an isopropylmalate dehydrogenase were confirmed to be redox regulated and involved in stomatal movement. This study creates an inventory of potential redox switches, and highlights a protein redox regulatory mechanism in guard cell ABA and MeJA signal transduction. PMID:24580573

  15. N-Methyl D-Aspartate Receptor Antagonist Kynurenic Acid Affects Human Cortical Development

    PubMed Central

    Bagasrawala, Inseyah; Zecevic, Nada; Radonjić, Nevena V.

    2016-01-01

    Kynurenic acid (KYNA), a neuroactive metabolite of tryptophan degradation, acts as an endogenous N-methyl-D-aspartate receptor (NMDAR) antagonist. Elevated levels of KYNA have been observed in pregnant women after viral infections and are considered to play a role in neurodevelopmental disorders. However, the consequences of KYNA-induced NMDAR blockade in human cortical development still remain elusive. To study the potential impact of KYNA on human neurodevelopment, we used an in vitro system of multipotent cortical progenitors, i.e., radial glia cells (RGCs), enriched from human cerebral cortex at mid-gestation (16–19 gestational weeks). KYNA treatment significantly decreased RGCs proliferation and survival by antagonizing NMDAR. This alteration resulted in a reduced number of cortical progenitors and neurons while number and activation of astrocytes increased. KYNA treatment reduced differentiation of RGCs into GABAergic neurons, while differentiation into glutamatergic neurons was relatively spared. Furthermore, in mixed cortical cultures KYNA triggered an inflammatory response as evidenced by increased levels of the pro-inflammatory cytokine IL-6. In conclusion, elevated levels of KYNA play a significant role in human RGC fate determination by antagonizing NMDARs and by activating an inflammatory response. The altered cell composition observed in cell culture following exposure to elevated KYNA levels suggests a mechanism for impairment of cortical circuitry formation in the fetal brain after viral infection, as seen in neurodevelopmental disorders such as schizophrenia. PMID:27746712

  16. 5-Amino-6-methyl-quinolin-1-ium hydrogen malonate-malonic acid (2/1).

    PubMed

    Thanigaimani, Kaliyaperumal; Khalib, Nuridayanti Che; Arshad, Suhana; Razak, Ibrahim Abdul

    2013-03-01

    The asymmetric unit of the title compound, 2C10H11N2(+)·2C3H3O4(-)·C3H4O4, consists of one 5-amino-6-methyl-quinolin-1-ium cation, one hydrogen malonate (2-carb-oxy-acetate) anion and one-half mol-ecule of malonic acid which lies on a twofold rotation axis. The quinoline ring system is essentially planar, with a maximum deviation of 0.062 (2) Å for all non-H atoms. In the anion, an intra-molecular O-H⋯O hydrogen bond generates an S(6) ring. In the crystal, the components are linked via N-H⋯O and O-H⋯O hydrogen bonds into layers parallel to the ac plane. The crystal structure also features weak C-H⋯O hydrogen bonds and a π-π stacking inter-action with a centroid-centroid distance of 3.8189 (10) Å.

  17. N-Methyl-d-aspartate Receptor Antagonists Have Variable Affect in 3-Nitropropionic Acid Toxicity

    PubMed Central

    Carbery, Timothy; Geddes, James W.

    2013-01-01

    There is accumulating evidence that excitotoxicity and oxidative stress resulting from excessive activation of glutamate (N-methyl-d-aspartate) NMDA receptors are major participants in striatal degeneration associated with 3-nitropropionic acid (3NP) administration. Although excitotoxic and oxidative mechanisms are implicated in 3NP toxicity, there are conflicting reports as to whether NMDA receptor antagonists attenuate or exacerbate the 3NP-induced neurodegeneration. In the present study, we investigated the involvement of NMDA receptors in striatal degeneration, protein oxidation and motor impairment following systemic 3NP administration. We examined whether NMDA receptor antagonists, memantine and ifenprodil, influence the neurotoxicity of 3NP. The development of striatal lesion and protein oxidation following 3NP administration is delayed by memantine but not affected by ifenprodil. However, in behavioral experiments, memantine failed to improve and ifenprodil exacerbated the motor deficits associated with 3NP toxicity. Together, these findings suggest caution in the application of NMDA receptor antagonists as a neuroprotective agent in neurodegenerative disorders associated with metabolic impairment. PMID:18688711

  18. N-methyl-D-aspartate receptor antagonists have variable affect in 3-nitropropionic acid toxicity.

    PubMed

    Nasr, Payman; Carbery, Timothy; Geddes, James W

    2009-03-01

    There is accumulating evidence that excitotoxicity and oxidative stress resulting from excessive activation of glutamate (N-methyl-D-aspartate) NMDA receptors are major participants in striatal degeneration associated with 3-nitropropionic acid (3NP) administration. Although excitotoxic and oxidative mechanisms are implicated in 3NP toxicity, there are conflicting reports as to whether NMDA receptor antagonists attenuate or exacerbate the 3NP-induced neurodegeneration. In the present study, we investigated the involvement of NMDA receptors in striatal degeneration, protein oxidation and motor impairment following systemic 3NP administration. We examined whether NMDA receptor antagonists, memantine and ifenprodil, influence the neurotoxicity of 3NP. The development of striatal lesion and protein oxidation following 3NP administration is delayed by memantine but not affected by ifenprodil. However, in behavioral experiments, memantine failed to improve and ifenprodil exacerbated the motor deficits associated with 3NP toxicity. Together, these findings suggest caution in the application of NMDA receptor antagonists as a neuroprotective agent in neurodegenerative disorders associated with metabolic impairment.

  19. Neuroprotection in rabbit retina with N-acetyl-aspartylglutamate and 2-phosphonyl-methyl pentanedioic acid

    NASA Astrophysics Data System (ADS)

    Hacker, Henry D.; Yourick, Debra L.; Koenig, Michael K.; Slusher, Barbara S.; Meyerhoff, James L.

    1999-06-01

    Retinal tissue is subject to ischemia from diabetic retinopathy and other conditions that affect the retinal vasculature such as lupus erythematosus and temporal arteritis. There is evidence in animal models of reversible ischemia that a therapeutic window exists during early recovery when agents that reduce glutamate activity at its receptor sites can rescue neurons from injury. To model ischemia, we used sodium cyanide (NaCN), to inhibit oxidative metabolism, and 2-deoxyglucose (2-DG) to inhibit glycolysis. Dissociated rabbit retina cells were studied to evaluate the potential neuroprotective effects of N-acetyl-aspartyl-glutamate (MAAG), which competes with glutamate as a low-potency agonist at the NMDA receptor complex. N-acetylated α-linked acidic dipeptidase (NAALADase; the NAAG-hydrolyzing enzyme) is responsible for the hydrolysis of NAAG into glutamate, a neurotransmitter and potent excitotoxin, and N-acetylaspartate. 2-Phosphonyl-methyl pentanedioic acid (PMPA) and β-linked NAAG (β-NAAG), inhibitors of NAALADase, were also tested, since inhibition of NAALADase could reduce synaptic glutamate and increase the concentration of NAAG. We found that metabolic inhibition with NaCN/2-DG for 1 hour caused 50% toxicity as assessed with the MTT assay. Co-treatment with NAAG resulted in dose-dependent protection of up to 55% (p<0.005). When the non-hydrolyzable, NAALADase inhibitor β-NAAG was employed dose-dependent protection of up to 37% was observed (p<0.001). PMPA also showed 48% protection (p<.05-.001) against these insults. These data suggest that NAAG may antagonize the effect of glutamate at the NMDA receptor complex in retina. Inhibition of NAALADase by PMPA and β-NAAG may increase the activity of endogenous NAAG.

  20. Crystal structure of di­methyl­ammonium hydrogen oxalate hemi(oxalic acid)

    PubMed Central

    Diallo, Waly; Gueye, Ndongo; Crochet, Aurélien; Plasseraud, Laurent; Cattey, Hélène

    2015-01-01

    Single crystals of the title salt, Me2NH2 +·HC2O4 −·0.5H2C2O4, were isolated as a side product from the reaction involving Me2NH, H2C2O4 and Sn(n-Bu)3Cl in a 1:2 ratio in methanol or by the reaction of the (Me2NH2)2C2O4 salt and Sn(CH3)3Cl in a 2:1 ratio in ethanol. The asymmetric unit comprises a di­methyl­ammonium cation (Me2NH2 +), an hydrogenoxalate anion (HC2O4 −), and half a mol­ecule of oxalic acid (H2C2O4) situated about an inversion center. From a supra­molecular point of view, the three components inter­act together via hydrogen bonding. The Me2NH2 + cations and the HC2O4 − anions are in close proximity through bifurcated N—H⋯(O,O) hydrogen bonds, while the HC2O4 − anions are organized into infinite chains via O—H⋯O hydrogen bonds, propagating along the a-axis direction. In addition, the oxalic acid (H2C2O4) mol­ecules play the role of connectors between these chains. Both the carbonyl and hydroxyl groups of each diacid are involved in four inter­molecular inter­actions with two Me2NH2 + and two HC2O4 − ions of four distinct polymeric chains, via two N—H⋯O and two O—H⋯O hydrogen bonds, respectively. The resulting mol­ecular assembly can be viewed as a two-dimensional bilayer-like arrangement lying parallel to (010), and reinforced by a C—H⋯O hydrogen bond. PMID:25995858

  1. Bioaccumulation patterns of methyl mercury and essential fatty acids in lacustrine planktonic food webs and fish.

    PubMed

    Kainz, Martin; Telmer, Kevin; Mazumder, Asit

    2006-09-01

    Organisms of the planktonic food web convey essential nutrients as well as contaminants to animals at higher trophic levels. We measured concentrations of methyl mercury (MeHg) and essential fatty acids (EFAs, key nutrients for aquatic food webs) in four size categories of planktonic organisms - seston (10-64 microm), micro-(100-200 microm), meso-(200-500 microm), and macrozooplankton (>500 microm) - as well as total mercury (THg) and EFAs in rainbow trout (Oncorhynchus mykiss) in coastal lakes. We demonstrate that, in all lakes during this summer sampling, MeHg concentrations of planktonic organisms increase significantly with plankton size, independent of their taxonomic composition, and that their MeHg accumulation patterns predict significantly THg concentrations in rainbow trout (R2=0.71, p<0.05). However, concentrations of total EFAs do not follow this pattern. Total EFAs increased from seston to mesozooplankton but decreased in the largest zooplankton size fraction. Moreover, concentrations of individual EFA compounds in rainbow trout are consistently lower, with the exception of docosahexaenoic acid, than those in macrozooplankton. The continuous increase of MeHg concentrations in aquatic organisms, therefore, differs from patterns of EFA accumulation in zooplankton and fish. We interpret these contrasting accumulation patterns of MeHg and EFA compounds as the inability of aquatic organisms to regulate the assimilation of dietary MeHg, whereas the rate of EFA retention may be controlled to optimize their physiological performance. Therefore, we conclude that bioaccumulation patterns of Hg in these aquatic food webs are not controlled by lipid solubility and/or the retention of EFA compounds.

  2. Regulation of tissue LC-PUFA contents, Δ6 fatty acyl desaturase (FADS2) gene expression and the methylation of the putative FADS2 gene promoter by different dietary fatty acid profiles in Japanese seabass (Lateolabrax japonicus).

    PubMed

    Xu, Houguo; Dong, Xiaojing; Ai, Qinghui; Mai, Kangsen; Xu, Wei; Zhang, Yanjiao; Zuo, Rantao

    2014-01-01

    The present study was conducted to evaluate the influences of different dietary fatty acid profiles on the tissue content and biosynthesis of LC-PUFA in a euryhaline species Japanese seabass reared in seawater. Six diets were prepared, each with a characteristic fatty acid: Diet PA: Palmitic acid (C16:0); Diet SA: Stearic acid (C18:0); Diet OA: Oleic acid (C18:1n-9); Diet LNA: α-linolenic acid (C18:3n-3); Diet N-3 LC-PUFA: n-3 LC-PUFA (DHA+EPA); Diet FO: the fish oil control. A 10-week feeding trial was conducted using juvenile fish (29.53 ± 0.86 g). The results showed that Japanese seabass had limited capacity to synthesize LC-PUFA and fish fed PA, SA, OA and LNA showed significantly lower tissue n-3 LC-PUFA contents compared to fish fed N-3 LC-PUFA and FO. The putative gene promoter and full-length cDNA of FADS2 was cloned and characterized. The protein sequence was confirmed to be homologous to FADS2s of marine teleosts and possessed all the characteristic features of microsomal fatty acid desaturases. The FADS2 transcript levels in liver of fish fed N-3 LC-PUFA and FO were significantly lower than those in fish fed other diets except LNA while Diet PA significantly up-regulated the FADS2 gene expression compared to Diet LNA, N-3 LC-PUFA and FO. Inversely, fish fed N-3 LC-PUFA and FO showed significantly higher promoter methylation rates of FADS2 gene compared to fish fed the LC-PUFA deficient diets. These results suggested that Japanese seabass had low LC-PUFA synthesis capacity and LC-PUFA deficient diets caused significantly reduced tissue n-3 LC-PUFA contents. The liver gene expression of FADS2 was up-regulated in groups enriched in C16:0, C18:0 and C18:1n-9 respectively but not in the group enriched in C18:3n-3 compared to groups with high n-3 LC-PUFA contents. The FADS2 gene expression regulated by dietary fatty acids was significantly negatively correlated with the methylation rate of putative FADS2 gene promoter.

  3. Silicon-mediated resistance of Arabidopsis against powdery mildew involves mechanisms other than the salicylic acid (SA)-dependent defence pathway.

    PubMed

    Vivancos, Julien; Labbé, Caroline; Menzies, James G; Bélanger, Richard R

    2015-08-01

    On absorption by plants, silicon (Si) offers protection against many fungal pathogens, including powdery mildews. The mechanisms by which Si exerts its prophylactic role remain enigmatic, although a prevailing hypothesis suggests that Si positively influences priming. Attempts to decipher Si properties have been limited to plants able to absorb Si, which excludes the model plant Arabidopsis because it lacks Si influx transporters. In this work, we were able to engineer Arabidopsis plants with an Si transporter from wheat (TaLsi1) and to exploit mutants (pad4 and sid2) deficient in salicylic acid (SA)-dependent defence responses to study their phenotypic response and changes in defence expression against Golovinomyces cichoracearum (Gc) following Si treatment. Our results showed that TaLsi1 plants contained significantly more Si and were significantly more resistant to Gc infection than control plants when treated with Si, the first such demonstration in a plant transformed with a heterologous Si transporter. The resistant plants accumulated higher levels of SA and expressed higher levels of transcripts encoding defence genes, thus suggesting a role for Si in the process. However, TaLsi1 pad4 and TaLsi1 sid2 plants were also more resistant to Gc than were pad4 and sid2 plants following Si treatment. Analysis of the resistant phenotypes revealed a significantly reduced production of SA and expression of defence genes comparable with susceptible controls. These results indicate that Si contributes to Arabidopsis defence priming following pathogen infection, but highlight that Si will confer protection even when priming is altered. We conclude that Si-mediated protection involves mechanisms other than SA-dependent defence responses.

  4. Synthesis and properties of poly(methyl methacrylate-2-acrylamido-2-methylpropane sulfonic acid)/PbS hybrid composite

    SciTech Connect

    Preda, N.; Rusen, E.; Musuc, A.; Enculescu, M.; Matei, E.; Marculescu, B.; Fruth, V.; Enculescu, I.

    2010-08-15

    The synthesis of a new hybrid composite based on PbS nanoparticles and poly(methyl methacrylate-2-acrylamido-2-methylpropane sulfonic acid) [P(MMA-AMPSA)] copolymer is reported. The chemical synthesis consists in two steps: (i) a surfactant-free emulsion copolymerization between methyl methacrylate and 2-acrylamido-2-methylpropane sulfonic acid and (ii) the generation of PbS particles in the presence of the P(MMA-AMPSA) latex, from the reaction between lead nitrate and thiourea. The composite was studied by scanning electron microscopy (SEM), X-ray diffraction, FTIR spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The microstructure observed using SEM proves that the PbS nanoparticles are well dispersed in the copolymer matrix. The X-ray diffraction measurements demonstrate that the PbS nanoparticles have a cubic rock salt structure. It was also found that the inorganic semiconductor nanoparticles improve the thermal stability of the copolymer matrix.

  5. Extraction, purification, methylation and GC-MS analysis of short-chain carboxylic acids for metabolic flux analysis.

    PubMed

    Tivendale, Nathan D; Jewett, Erin M; Hegeman, Adrian D; Cohen, Jerry D

    2016-08-15

    Dynamic metabolic flux analysis requires efficient and effective methods for extraction, purification and analysis of a plethora of naturally-occurring compounds. One area of metabolism that would be highly informative to study using metabolic flux analysis is the tricarboxylic acid (TCA) cycle, which consists of short-chain carboxylic acids. Here, we describe a newly-developed method for extraction, purification, derivatization and analysis of short-chain carboxylic acids involved in the TCA cycle. The method consists of snap-freezing the plant material, followed by maceration and a 12-15h extraction at -80 °C. The extracts are then subject to reduction (to stabilize β-keto acids), purified by strong anion exchange solid phase extraction and methylated with methanolic HCl. This method could also be readily adapted to quantify many other short-chain carboxylic acids.

  6. Mathematical method for the prediction of retention times of fatty acid methyl esters in temperature-programmed capillary gas chromatography.

    PubMed

    Torres, Alexandre G; Trugo, Nádia M F; Trugo, Luiz C

    2002-07-17

    An accurate method for identification of fatty acids in complex mixtures analyzed by temperature-programmed capillary gas chromatography is described. The method is based on a mathematical approach using regression curves obtained by plotting the relative retention times of fatty acid methyl esters (FAMEs) analyzed in isothermal and gradient temperature conditions. The method was applied to a complex biological sample (human milk), and it was possible to identify 64 fatty acids, including branched-chain and other fatty acids for which reference standards were not readily available. The identities of the majority of the peaks were confirmed by mass spectrometry. The relative residuals and the relative differences between estimated and measured relative retention times of individual FAMEs varied from 0.03 to 3.15% and from 0.0 to 2.9%, respectively. The method is useful for identification of fatty acids in routine analysis.

  7. Assisted reproductive technology alters deoxyribonucleic acid methylation profiles in bloodspots of newborn infants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the effect of infertility and intracytoplasmic sperm injection (ICSI) on DNA methylation of offspring. Microarray analysis of DNA methylation in archived neonatal bloodspots of in vitro fertilization (IVF)/ICSI-conceived children compared with controls born to fertile and infertile paren...

  8. Noncatalytic mono-N-methylation of aniline in supercritical methanol: the kinetics and acid/base effect.

    PubMed

    Takebayashi, Yoshihiro; Morita, Yoshinori; Sakai, Hideki; Abe, Masahiko; Yoda, Satoshi; Furuya, Takeshi; Sugeta, Tsutomu; Otake, Katsuto

    2005-08-21

    Aniline is easily N-methylated in supercritical methanol without catalyst at 350 degrees C and 0.237 g cm-3 to give mono-N-methylaniline with high selectivity, and the reaction rate is increased by a small amount of base (LiOH, NaOH, KOH, and CH3ONa), indicating a difference in the reaction mechanism from the ordinary acid-catalyzed one.

  9. Simultaneous liquid-liquid microextraction/methylation for the determination of haloacetic acids in drinking waters by headspace gas chromatography.

    PubMed

    Cardador, M J; Serrano, A; Gallego, M

    2008-10-31

    A novel analytical method that combines simultaneous liquid-liquid microextraction/methylation and headspace gas chromatography-mass spectrometry for the determination of nine haloacetic acids (HAAs) in water was reported. A mechanistic model on the basis of mass transfer with chemical reaction in which methylation of HAAs was accomplished in n-pentane-water (150 microl-10 ml) two-phase system with a tetrabutylammonium salt as phase transfer catalyst was proposed. Derivatisation with dimethylsulphate was completed in 3 min by shaking at room temperature. The methyl ester derivatives and the organic phase were completely volatilised by static headspace technique, being the gaseous phase analysed. Parameters related to the extraction/methylation and headspace generation of HAAs were studied and the results were compared with methyl haloacetate standards to establish the yield of each step. The thermal instability of HAAs, by degradation to their respective halogenated hydrocarbon by decarboxylation, and the possible hydrolysation of the methyl esters were rigorously controlled in the whole process to obtain a reliable and robust method. The proposed method yielded detection limits very low which ranges from 0.02 to 0.4 microg l(-1) and a relative standard deviation of ca. 7.5%. Finally, the method was validated with the US Environmental Protection Agency (EPA) method 552.2 for the analysis of HAAs in drinking and swimming pool water samples containing concentrations of HAAs that must be higher than 10 microg l(-1) due to the fact that this method is less sensitive than the proposed one.

  10. Conversion of polar and non-polar algae oil lipids to fatty acid methyl esters with solid acid catalysts--A model compound study.

    PubMed

    Asikainen, Martta; Munter, Tony; Linnekoski, Juha

    2015-09-01

    Bio-based fuels are becoming more and more important due to the depleting fossil resources. The production of biodiesel from algae oil is challenging compared to terrestrial vegetable oils, as algae oil consists of polar fatty acids, such as phospholipids and glycolipids, as well as non-polar triglycerides and free fatty acids common in vegetable oils. It is shown that a single sulphonated solid acid catalyst can perform the esterification and transesterification reactions of both polar and non-polar lipids. In mild reaction conditions (60-70 °C) Nafion NR50 catalyst produces methyl palmitate (FAME) from the palmitic acid derivatives of di-, and tri-glyceride, free fatty acid, and phospholipid with over 80% yields, with the glycolipid derivative giving nearly 40% yields of FAME. These results demonstrate how the polar and non-polar lipid derivatives of algal oil can be utilised as feedstocks for biodiesel production with a single catalyst in one reaction step.

  11. Genomic DNA Methylation Changes in Response to Folic Acid Supplementation in a Population-Based Intervention Study among Women of Reproductive Age

    PubMed Central

    Berry, Robert J.; Hao, Ling; Li, Zhu; Maneval, David; Yang, Thomas P.; Rasmussen, Sonja A.; Yang, Quanhe; Zhu, Jiang-Hui; Hu, Dale J.; Bailey, Lynn B.

    2011-01-01

    Folate is a source of one-carbons necessary for DNA methylation, a critical epigenetic modification necessary for genomic structure and function. The use of supplemental folic acid is widespread however; the potential influence on DNA methylation is unclear. We measured global DNA methylation using DNA extracted from samples from a population-based, double-blind randomized trial of folic acid supplementation (100, 400, 4000 µg per day) taken for 6 months; including a 3 month post-supplementation sample. We observed no changes in global DNA methylation in response to up to 4,000 µg/day for 6 months supplementation in DNA extracted from uncoagulated blood (approximates circulating blood). However, when DNA methylation was determined in coagulated samples from the same individuals at the same time, significant time, dose, and MTHFR genotype-dependent changes were observed. The baseline level of DNA methylation was the same for uncoagulated and coagulated samples; marked differences between sample types were observed only after intervention. In DNA from coagulated blood, DNA methylation decreased (−14%; P<0.001) after 1 month of supplementation and 3 months after supplement withdrawal, methylation decreased an additional 23% (P<0.001) with significant variation among individuals (max+17%; min-94%). Decreases in methylation of ≥25% (vs. <25%) after discontinuation of supplementation were strongly associated with genotype: MTHFR CC vs. TT (adjusted odds ratio [aOR] 12.9, 95%CI 6.4, 26.0). The unexpected difference in DNA methylation between DNA extracted from coagulated and uncoagulated samples in response to folic acid supplementation is an important finding for evaluating use of folic acid and investigating the potential effects of folic acid supplementation on coagulation. PMID:22163281

  12. Hydrolysis of substance P in the presence of the osteosarcoma cell line SaOS-2: release of free amino acids.

    PubMed

    Cavazza, Antonella; Marini, Mario; Roda, L Giorgio; Tarantino, Umberto; Valenti, Angela

    2011-12-01

    The possible hydrolysis of substance P (Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met) in presence of the osteoblastic cell line SaOS-2 was measured by capillary electrophoresis coupled to mass detection. The results obtained indicate that a very rapid disappearance of the intact undecapeptide was associated to a slower appearance of seven of its eight component amino acids. These results can be interpreted as indicating that an extremely fast hydrolysis of substance P by endopeptidases, which released peptidic by-products, was followed by a noticeably slower secondary degradation which released free amino acids. In decreasing quantitative importance, these phenomena appear to originate by the hydrolysis of the Pro(4)-Gln(5) bond, followed by C-terminal sequential degradation of the Arg(1)-Pro(4) tetrapeptide; by the hydrolysis of or Phe(7)-Phe(8) bond (or, possibly, of Gln(6)-Phe(7)) leading to release of free Phe and Gln; by hydrolysis of the Gly(9)-Leu(10) bond with subsequent release of Met and Leu. Results obtained appear to be compatible with the expression by SaOS-2 cells of enzymes already known to catalyze substance P hydrolysis, together with an apparent low efficiency of aminopeptidases. Because of the activity of C-terminal fragments on NK1 receptors, the delay between primary hydrolysis of substance P and secondary hydrolysis of its peptidic fragments indicated by the data shown implies a possible persistence of substance P physiological effects even after degradation of the intact peptide.

  13. Methyl 2-((succinimidooxy)carbonyl)benzoate (MSB): a new, efficient reagent for N-phthaloylation of amino acid and peptide derivatives.

    PubMed

    Casimir, J Richard; Guichard, Gilles; Briand, Jean-Paul

    2002-05-31

    A new, efficient, and readily available reagent, methyl 2-((succinimidooxy)carbonyl)benzoate (MSB), for N-phthaloylation of amino acids and amino acid derivatives is described. The phthaloylation procedure is simple and racemization-free and gives excellent results with alpha-amino acids, alpha-amino alcohols, dipeptides, alpha-amino carboxamides, and alpha-amino esters.

  14. Analytical strategy for the molecular weight determination of random copolymers of poly(methyl methacrylate) and poly(methacrylic acid).

    PubMed

    Giordanengo, Rémi; Viel, Stéphane; Hidalgo, Manuel; Allard-Breton, Béatrice; Thévand, André; Charles, Laurence

    2010-06-01

    Molecular weight characterization of random amphiphilic copolymers currently represents an analytical challenge. In particular, molecules composed of methacrylic acid (MAA) and methyl methacrylate (MMA) as the repeat units raise issues in commonly used techniques. The present study shows that when random copolymers cannot be properly ionized by MALDI, and hence detected and measured in MS, one possible analytical strategy is to transform them into homopolymers, which are more amenable to this ionization technique. Then, by combining the molecular weight of the so-obtained homopolymers, as measured by MS, with the relative molar proportion of the MMA and MMA units, as given by (1)H NMR spectrum, one can straightforwardly estimate the molecular weight of the initial copolymer. A methylation reaction was performed to transform MAA-MMA copolymer samples into PMMA homopolymers, using trimethylsilyldiazomethane as a derivatization agent. Weight average molecular weight (M(w)) parameters of the MAA-MMA copolymers could then be derived from M(w) values obtained for the methylated MAA-MMA molecules by MALDI, which were also validated by pulsed gradient spin echo (PGSE) NMR. An alkene function in one of the studied copolymer end-groups was also shown to react with the methylation agent, giving rise to MMA-like polymeric by-products characterized by tandem mass spectrometry and which could be avoided by adjusting the amount of the trimethylsilyldiazomethane in the reaction medium.

  15. Synthesis of hollow silver spheres using poly-(styrene-methyl acrylic acid) as templates in the presence of sodium polyacrylate

    NASA Astrophysics Data System (ADS)

    Wang, Aili; Yin, Hengbo; Ge, Chen; Ren, Min; Liu, Yumin; Jiang, Tingshun

    2010-02-01

    Hollow silver spheres were successfully prepared by reducing AgNO 3 with ascorbic acid and using negatively charged poly-(styrene-methyl acrylic acid) (PSA) spheres as templates in the presence of sodium polyacrylate as a stabilizer. Firstly, silver cations adsorbed on the surface of PSA spheres via electrostatic attraction between the carboxyl groups and silver cations were reduced in situ by ascorbic acid. The silver nanoparticles deposited on the surface of PSA spheres served as seeds for the further growth of silver shells. After that, extra amount of AgNO 3 and ascorbic acid solutions were added to form PSA/Ag composites with thick silver shells. In order to obtain compact silver shells, the as-prepared PSA/Ag composites were heated at 150 °C for 3 h. Then hollow silver spheres were prepared by dissolving PSA templates with tetrahydrofuran.

  16. Formation of molecular complexes of salicylic acid, acetylsalicylic acid, and methyl salicylate in a mixture of supercritical carbon dioxide with a polar cosolvent

    NASA Astrophysics Data System (ADS)

    Petrenko, V. E.; Antipova, M. L.; Gurina, D. L.; Odintsova, E. G.

    2015-08-01

    The solvate structures formed by salicylic acid, acetylsalicylic acid, and methyl salicylate in supercritical (SC) carbon dioxide with a polar cosolvent (methanol, 0.03 mole fractions) at a density of 0.7 g/cm3 and a temperature of 318 K were studied by the molecular dynamics method. Salicylic and acetylsalicylic acids were found to form highly stable hydrogen-bonded complexes with methanol via the hydrogen atom of the carboxyl group. For methyl salicylate in which the carboxyl hydrogen is substituted by a methyl radical, the formation of stable hydrogen bonds with methanol was not revealed. The contribution of other functional groups of the solute to the interactions with the cosolvent was much smaller. An analysis of correlations between the obtained data and the literature data on the cosolvent effect on the solubility of the compounds in SC CO2 showed that the dissolving ability of SC CO2 with respect to a polar organic substance in the presence of a cosolvent increased only when stable hydrogen-bonded complexes are formed between this substance and the cosolvent.

  17. Very-long-chain 3-hydroxy fatty acids, 3-hydroxy fatty acid methyl esters and 2-alkanols from cuticular waxes of Aloe arborescens leaves.

    PubMed

    Racovita, Radu C; Peng, Chen; Awakawa, Takayoshi; Abe, Ikuro; Jetter, Reinhard

    2015-05-01

    The present work aimed at a comprehensive chemical characterization of the cuticular wax mixtures covering leaves of the monocot species Aloe arborescens. The wax mixtures were found to contain typical aliphatic compound classes in characteristic chain length distributions, including alkanes (predominantly C31), primary alcohols (predominantly C28), aldehydes (predominantly C32), fatty acid methyl esters (predominantly C28) and fatty acids (bimodal distribution around C32 and C28). Alkyl esters ranging from C42 to C52 were identified, and found to mainly contain C28 alcohol linked to C16-C20 acids. Three other homologous series were identified as 3-hydroxy fatty acids (predominantly C28), their methyl esters (predominantly C28), and 2-alkanols (predominantly C31). Based on structural similarities and homolog distributions, the biosynthetic pathways leading to these novel wax constituents can be hypothesized. Further detailed analyses showed that the A. arborescens leaf was covered with 15 μg/cm(2) wax on its adaxial side and 36 μg/cm(2) on the abaxial side, with 3:2 and 1:1 ratios between epicuticular and intracuticular wax layers on each side, respectively. Terpenoids were found mainly in the intracuticular waxes, whereas very-long-chain alkanes and fatty acids accumulated to relatively high concentrations in the epicuticular wax, hence near the true surface of the leaf.

  18. Design, synthesis, and evaluation of omega-iodovinyl- and omega-iodoalkyl-substituted methyl-branched long-chain fatty acids

    SciTech Connect

    Goodman, M.M.; Callahan, A.P.; Knapp, F.F. Jr.

    1985-06-01

    The synthesis of a new methyl-branched fatty acid, (E)-19-iodo-3(RS)-methyl-18-nonadecenoic acid (19), is described. Methyl branching has been introduced at the 3-position to inhibit beta-oxidation and radioiodide has been attached as a trans-vinyl iodide. Preparation of 19 involved a 15-step sequence of reactions climaxing with formation of the methyl ester 18 by iododestannylation of methyl (E)-19-(tri-n-butylstannyl)-3(RS)-methyl-18-nonadecenoate (17) resulting from the reaction of n-Bu3SnH with methyl 3(RS)-methyl-18-nonadecynoate (16). Methyl branching was introduced at an early stage by Friedel-Crafts acylation of thiophene with 3(RS)-methyl-4-carbomethoxybutanoyl chloride (3) generated from 3-methylglutaric anhydride. The new agent, (/sup 125/I)-19, showed high myocardial uptake (5 min, 4.89% dose/g; 30 min, 3.32% dose/g), good heart/blood (H/B) ratios (5 min, 5.4/1; 30 min, 4.3/1), and significantly greater myocardial retention in fasted rats than the corresponding straight-chain analogue 19-(/sup 125/I)-iodo-18-nonadecenoic acid (5 min, 3.52% dose/g, H/B = 4.8/1; 30 min, 1.19% dose/g, H/B = 1.6/1). Excellent myocardial images were obtained in rats after administration of (123I)-19 and confirmed the slow myocardial washout over a 60-min period. These data suggest that 19 is a good candidate for evaluation of heart disease involving aberrations in fatty acid metabolism by use of imaging techniques such as single photon emission computerized tomography (SPECT) where redistribution or washout should be minimized.

  19. Friedel-crafts alkylation of benzene by normal omega-chloroalkanoic acids and their methyl esters and nitriles

    SciTech Connect

    Zakharkin, L.I.; Anikina, E.V.

    1987-08-20

    In the Friedel-Crafts alkylation of benzene by normal 1-haloalkanes with three or more carbon atoms a mixture of phenylalkanes forms, due to isomerization of the alkyl chain and migration of a hydrogen atoms. Under analogous conditions the alkylation of benzene by omega-chloroalkanoic acids, Cl(CH/sub 2/)/sub n/COOH, and omega-bromoalkanonitriles proceeds with isomerization of the alkyl chain, but beginning only with 6-chlorohexanoic acid and 6-bromohexanonitrile. Such a difference in the behavior of these halogen derivatives has not received a convincing explanation, although the mechanism of Friedel-Crafts alkylation of benzene should be the same in the two cases. For a better understanding of this difference, this work presents a systematic study of benzene alkylation by 4-chlorobutyric, 5-chlorovaleric, 6-chlorohexanoic, and 7-chloroheptanoic acids and their methyl esters and nitriles, and by ..gamma..-butyro- and delta-valerolactones. The catalyst was crystalline AlCl/sub 3/ twice sublimed from Mg. For comparison, alkylation with the respective 1-chloroalkanes was carried out. In the alkylation of benzene by omega-chloroalkanoic acids Cl(CH/sub 2/)/sub n/COOH (where n = 3-6) and their methyl esters and nitriles, in the presence of AlCl/sub 3/, the degree of isomerization of the alkyl chain is less than with the corresponding 1-chloroalkanes, depending on the increase in electron acceptor activity in the sequence HOOC- > CH/sub 3/OCO- > CN-.

  20. The effects of growth temperature on the methyl sterol and phospholipid fatty acid composition of Methylococcus capsulatus (Bath)

    NASA Technical Reports Server (NTRS)

    Jahnke, L. L.

    1992-01-01

    Growth of Methylococcus capsulatus (Bath) at temperatures ranging from 30 to 50 degrees C resulted in changes to the whole cell lipid constituents. As temperature was lowered, the overall proportion of hexadecenoic acid (C16:1) increased, and the relative proportions of the delta 9, delta 10 and delta 11 C16:1 double bond positional isomers changed. Methyl sterol content also increased as the growth temperature was lowered. The highest amounts of methyl sterol were found in 30 degrees C cells and the lowest in 50 degrees C cells (sterol-phospholipid ratios of 0.077 and 0.013, respectively). The data are consistent with a membrane modulating role for the sterol produced by this prokaryotic organism.

  1. The effects of growth temperature on the methyl sterol and phospholipid fatty acid composition of Methylococcus capsulatus (Bath)

    NASA Technical Reports Server (NTRS)

    Jahnke, Linda L.

    1992-01-01

    Growth of Methylococcus capsulatus (Bath) at temperatures ranging from 30 to 50 C resulted in changes to the whole cell lipid constituents. As temperature was lowered, the overall proportion of hexadecenoic acid (C16:1) increased, and the relative proportions of the Delta9, Delta10, and Delta11 C16:1 double bond positional isomers changed. Methyl sterol content also increased as the growth temperature was lowered. The highest amounts of methyl sterol were found in 30 C cells and the lowest in 50 C cells (sterol-phospholipid ratios of 0.077 and 0.013, respectively). The data are consistent with a membrane modulating role for the sterol produced by this prokaryotic organism.

  2. Labdanolic acid methyl ester (LAME) exerts anti-inflammatory effects through inhibition of TAK-1 activation

    SciTech Connect

    Cuadrado, Irene; Estevez-Braun, Ana; Heras, Beatriz de las

    2012-01-01

    Labdane derivatives obtained from the diterpenoid labdanediol suppressed NO and PGE{sub 2} production in LPS-stimulated RAW 264.7 macrophages. However, mechanisms involved in these inhibitory effects are not elucidated. In this study, we investigated the signaling pathways involved in the anti-inflammatory effects of labdanolic acid methyl ester (LAME) in peritoneal macrophages and examined its therapeutic effect in a mouse endotoxic shock model. LAME reduced the production of NO and PGE{sub 2} in LPS-activated macrophages. This effect involved the inhibition of NOS-2 and COX-2 gene expression, acting at the transcription level. Examination of the effects of the diterpene on NF-κB signaling showed that LAME inhibits the phosphorylation of IκBα and IκBβ, preventing their degradation and the nuclear translocation of the NF-κB p65 subunit. Moreover, inhibition of MAPK signaling was also observed. A further experiment revealed that LAME inhibited the phosphorylation of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1), an upstream signaling molecule required for IKK and mitogen-activated protein kinases (MAPKs) activation. Inflammatory cytokines such as IL-6, TNF-α and IP-10 were downregulated in the presence of this compound after stimulation with LPS. Additionally, LAME also improved survival in a mouse model of endotoxemia and reduced the circulatory levels of cytokines (IL-6, TNF-α). In conclusion, these results indicate that labdane diterpene LAME significantly attenuates the pro-inflammatory response induced by LPS both in vivo and in vitro. Highlights: ► LAME reduced the production of NO and PGE{sub 2} in LPS-activated macrophages. ► IL-6, TNF-α and IP-10 were also inhibited by LAME. ► Inhibition of TAK-1 activation is the mechanism involved in this process. ► LAME improved survival in a mouse model of endotoxemia. ► LAME reduced the circulatory levels of cytokines (IL-6, TNF-α).

  3. Separation of the fatty acids in menhaden oil as methyl esters with a highly polar ionic liquid gas chromatographic column and identification by time of flight mass spectrometry.

    PubMed

    Fardin-Kia, Ali Reza; Delmonte, Pierluigi; Kramer, John K G; Jahreis, Gerhard; Kuhnt, Katrin; Santercole, Viviana; Rader, Jeanne I

    2013-12-01

    The fatty acids contained in marine oils or products are traditionally analyzed by gas chromatography using capillary columns coated with polyethylene glycol phases. Recent reports indicate that 100 % cyanopropyl siloxane phases should also be used when the analyzed samples contain trans fatty acids. We investigated the separation of the fatty acid methyl esters prepared from menhaden oil using the more polar SLB-IL111 (200 m × 0.25 mm) ionic liquid capillary column and the chromatographic conditions previously optimized for the separation of the complex mixture of fatty acid methyl esters prepared from milk fat. Identifications of fatty acids were achieved by applying Ag(+)-HPLC fractionation and GC-TOF/MS analysis in CI(+) mode with isobutane as the ionization reagent. Calculation of equivalent chain lengths confirmed the assignment of double bond positions. This methodology allowed the identification of 125 fatty acids in menhaden oil, including isoprenoid and furanoid fatty acids, and the novel 7-methyl-6-hexadecenoic and 7-methyl-6-octadecenoic fatty acids. The chromatographic conditions applied in this study showed the potential of separating in a single 90-min analysis, among others, the short chain and trans fatty acids contained in dairy products, and the polyunsaturated fatty acids contained in marine products.

  4. [Epigenetic heredity (deoxyribonucleic acid methylation): Clinical context in neurodegenerative disorders and ATXN2 gene].

    PubMed

    Laffita-Mesa, José Miguel; Bauer, Peter

    2014-10-21

    Epigenetics is the group of changes in the phenotype which are related with the process independently of the primary DNA sequence. These changes are intimately related with changes in the gene expression level and its profile across the body. These are mediated by histone tail modifications, DNA methylation, micro-RNAs, with chromatin remodeling remaining as the foundation of epigenetic changes. DNA methylation involves the covalent addition of methyl group to cytosine of the DNA, which is mediated by methyltransferases enzymes. DNA methylation regulates gene expression by repressing transcription, while de-methylation activates gene transcription. Several human diseases are related with the epigenetic process: cancer, Alzheimer disease, stroke, Parkinson disease, and diabetes. We present here the basis of epigenetic inheritance and show the pathogenic mechanisms relating epigenetics in human diseases, specifically with regard to neurodegeneration. We discuss current concepts aimed at understanding the contribution of epigenetics to human neurodegenerative diseases. We also discuss recent findings obtained in our and other centers regarding the ATXN2 gene that causes spinocerebellar ataxia 2 and amyotrophic lateral sclerosis. Epigenetics play a pivotal role in the pathogenesis of human diseases and in several neurodegenerative disorders, and this knowledge will illuminate the pathways in the diagnostic and therapeutic field, which ultimately will be translated into the clinic context of neurodegenerative diseases.

  5. Comparison of four extraction/methylation analytical methods to measure fatty acid composition by gas chromatography in meat.

    PubMed

    Juárez, M; Polvillo, O; Contò, M; Ficco, A; Ballico, S; Failla, S

    2008-05-09

    Four different extraction-derivatization methods commonly used for fatty acid analysis in meat (in situ or one-step method, saponification method, classic method and a combination of classic extraction and saponification derivatization) were tested. The in situ method had low recovery and variation. The saponification method showed the best balance between recovery, precision, repeatability and reproducibility. The classic method had high recovery and acceptable variation values, except for the polyunsaturated fatty acids, showing higher variation than the former methods. The combination of extraction and methylation steps had great recovery values, but the precision, repeatability and reproducibility were not acceptable. Therefore the saponification method would be more convenient for polyunsaturated fatty acid analysis, whereas the in situ method would be an alternative for fast analysis. However the classic method would be the method of choice for the determination of the different lipid classes.

  6. Genetic and epigenetic transgenerational implications related to omega-3 fatty acids. Part I: maternal FADS2 genotype and DNA methylation correlate with polyunsaturated fatty acid status in toddlers: an exploratory analysis.

    PubMed

    Lupu, Daniel S; Cheatham, Carol L; Corbin, Karen D; Niculescu, Mihai D

    2015-11-01

    Polyunsaturated fatty acid metabolism in toddlers is regulated by a complex network of interacting factors. The contribution of maternal genetic and epigenetic makeup to this milieu is not well understood. In a cohort of mothers and toddlers 16 months of age (n = 65 mother-child pairs), we investigated the association between maternal genetic and epigenetic fatty acid desaturase 2 (FADS2) profiles and toddlers' n-6 and n-3 fatty acid metabolism. FADS2 rs174575 variation and DNA methylation status were interrogated in mothers and toddlers, as well as food intake and plasma fatty acid concentrations in toddlers. A multivariate fit model indicated that maternal rs174575 genotype, combined with DNA methylation, can predict α-linolenic acid plasma concentration in all toddlers and arachidonic acid concentrations in boys. Arachidonic acid intake was predictive for its plasma concentration in girls, whereas intake of 3 major n-3 species (eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were predictive for their plasma concentrations in boys. FADS2 genotype and DNA methylation in toddlers were not related to plasma concentrations or food intakes, except for CpG8 methylation. Maternal FADS2 methylation was a predictor for the boys' α-linolenic acid intakes. This exploratory study suggests that maternal FADS2 genetic and epigenetic status could be related to toddlers' polyunsaturated fatty acid metabolism.

  7. 4-[18F]Fluoro-N-methyl-N-(propyl-2-yn-1-yl)benzenesulfonamide ([18F]F-SA): a versatile building block for labeling of peptides, proteins and oligonucleotides with fluorine-18 via Cu(I)-mediated click chemistry.

    PubMed

    Ramenda, Theres; Steinbach, Jörg; Wuest, Frank

    2013-04-01

    Cu(I)-mediated [3+2]cycloaddition between azides and alkynes has evolved into a valuable bioconjugation tool in radiopharmaceutical chemistry. We have developed a simple, convenient and reliable radiosynthesis of 4-[18F]fluoro-N-methyl-N-(propyl-2-yn-1-yl)benzenesulfonamide ([18F]F-SA) as a novel aromatic sulfonamide-based click chemistry building block. [18F]F-SA could be prepared in a remotely controlled synthesis unit in 32 ± 5% decay-corrected radiochemical yield in a total synthesis time of 80 min. The determined lipophilicity of [18F]F-SA (logP = 1.7) allows handling of the radiotracer in aqueous solutions. The versatility of [18F]F-SA as click chemistry building block was demonstrated by the labeling of a model peptide (phosphopeptide), protein (HSA), and oligonucleotide (L-RNA). The obtained radiochemical yields were 77% (phosphopeptide), 55-60% (HSA), and 25% (L-RNA), respectively. Despite the recent emergence of a multitude of highly innovative novel bioconjugation methods for 18F labeling of biopolymers, Cu(I)-mediated click chemistry with [18F]F-SA represents a reliable, robust and efficient radiolabeling technique for peptides, proteins, and oligonucleotides with the short-lived positron emitter 18F.

  8. Nematocidal effects of natural phytoregulators jasmonic acid and methyl-jasmonate against Pratylenchus zeae and Helicotylenchus spp.

    PubMed

    Gavin, Amanda Salomão; Faggion, Silmara Aparecida; Hernandes, Camila; Lourenço, Mirian Vergínia; França, Suzelei de Castro; Beleboni, Rene Oliveira

    2013-01-01

    The aim of this study was to evaluate the nematocidal effects of natural phytoregulators jasmonic acid (JA) and methyl-jasmonate (MJ) against plant parasitic nematodes Pratylenchus zeae (Graham) (Pratylenchidae) and Helicotylenchus spp. (Hoplolaimidae). Both JA and MJ promoted elevated percentages of mortality in P. zeae and Helicotylenchus spp. after 12 and 24 h of nematodes exposition at different concentrations of jasmonates. Considering the potential use of jasmonates as biofertiliser added now for their nematocidal effects, our results are of relevance in terms of biotechnological application.

  9. Chemical constituents of Malagasy liverworts, part II: mastigophoric acid methyl ester of biogenetic interest from Mastigophora diclados (Lepicoleaceae Subf. Mastigophoroideae).

    PubMed

    Harinantenaina, Liva; Asakawa, Yoshinori

    2004-11-01

    In the course of our chemotaxonomic study of the liverworts growing in Madagascar, mastigophoric acid methyl ester, along with eleven known compounds were isolated from Mastigophora diclados. Isolated metabolites showed that the Malagasy Mastigophora is more related to the samples from Borneo and Japan than to the Taiwanese or Malaysian ones. The biosynthesis of the herbertane type sesquiterpenoids from Mastigophora diclados is suggested to be similar to those found in the genus Herbertus. The herbertane-type sesquiterpenoids were screened for Staphylococcus aureus strain inhibition.

  10. Homology Modeling of Human γ-Butyric Acid Transporters and the Binding of Pro-Drugs 5-Aminolevulinic Acid and Methyl Aminolevulinic Acid Used in Photodynamic Therapy

    PubMed Central

    Baglo, Yan; Gabrielsen, Mari; Sylte, Ingebrigt; Gederaas, Odrun A.

    2013-01-01

    Photodynamic therapy (PDT) is a safe and effective method currently used in the treatment of skin cancer. In ALA-based PDT, 5-aminolevulinic acid (ALA), or ALA esters, are used as pro-drugs to induce the formation of the potent photosensitizer protoporphyrin IX (PpIX). Activation of PpIX by light causes the formation of reactive oxygen species (ROS) and toxic responses. Studies have indicated that ALA and its methyl ester (MAL) are taken up into the cells via γ-butyric acid (GABA) transporters (GATs). Uptake via GATs into peripheral sensory nerve endings may also account for one of the few adverse side effects of ALA-based PDT, namely pain. In the present study, homology models of the four human GAT subtypes were constructed using three x-ray crystal structures of the homologous leucine transporter (LeuT) as templates. Binding of the native substrate GABA and the possible substrates ALA and MAL was investigated by molecular docking of the ligands into the central putative substrate binding sites in the outward-occluded GAT models. Electrostatic potentials (ESPs) of the putative substrate translocation pathway of each subtype were calculated using the outward-open and inward-open homology models. Our results suggested that ALA is a substrate of all four GATs and that MAL is a substrate of GAT-2, GAT-3 and BGT-1. The ESP calculations indicated that differences likely exist in the entry pathway of the transporters (i.e. in outward-open conformations). Such differences may be exploited for development of inhibitors that selectively target specific GAT subtypes and the homology models may hence provide tools for design of therapeutic inhibitors that can be used to reduce ALA-induced pain. PMID:23762315

  11. Omega-3 Polyunsaturated Fatty Acids Inhibited Tumor Growth via Preventing the Decrease of Genomic DNA Methylation in Colorectal Cancer Rats.

    PubMed

    Huang, Qionglin; Wen, Juan; Chen, Guangzhao; Ge, Miaomiao; Gao, Yihua; Ye, Xiaoxia; Liu, Chunan; Cai, Chun

    2016-01-01

    Omge-3 polyunsaturated fatty acids (PUFAs) exhibited significant effect in inhibiting various tumors. However, the mechanisms of its anticancer role have not been fully demonstrated. The declination of 5-methylcytosine (5 mC) was closely associated with poor prognosis of tumors. To explore whether omega-3 PUFAs influences on DNA methylation level in tumors, colorectal cancer (CRC) rat model were constructed using N-methyl phosphite nitrourea and omega-3 PUFAs were fed to part of the rats during tumor induction. The PUFAs contents in the rats of 3 experimental groups were measured using gas chromatography and 5 mC level were detected by liquid chromatography tandem mass spectrometry. The results showed that tumor incidence in omega-3 treated rats was much lower than in CRC model rats, which confirmed significant antitumor role of omega-3 PUFAs. Six PUFA members categorized to omega-3 and omega-6 families were quantified and the ratio of omega-6/omega-3 PUFAs was remarkably lower in omega-3 PUFAs treatment group than in CRC model group. 5 mC content in omega-3 PUFAs treated rats was higher than in CRC model rats, suggesting omega-3 PUFAs promoted 5 mC synthesis. Therefore, omega-3 PUFAs probably inhibited tumor growth via regulating DNA methylation process, which provided a novel anticancer mechanism of omega-3 PUFAs from epigenetic view.

  12. Content of N-6 methyl adenylic acid in heterogeneous nuclear and messenger RNA of HeLa cells.

    PubMed Central

    Lavi, U; Fernandez-Muñoz, R; Darnell, J E

    1977-01-01

    With the aid of a suitable thin layer chromatographic procedure, the N-6 methyl adenylic acid (m6A), content of a variety of 32P labeled RNA species from HeLa cells has been measured. Poly(A)-containing (poly(A)+) cytoplasmic RNA has on the average one m6Ap per 800 to 900 nucleotides. This value is independent of the length of the molecules. The proportion of m6Ap in poly(A)+ cytoplasmic RNA does not change between 4 and 18 hours of labeling with 32P, suggesting that the majority of the messenger RNA molecules may have a similar level of internal methylation regardless of their half-life. The non-polyadenylated, non-ribosomal cytoplasmic RNA fraction sedimenting from 10S TO 28S is less methylated with approximately one m6A per 2,700 nucleotides. Heterogeneous nuclear RNA molecules (DMSO treated) which sediment from 28S to 45S have approximately one m6Ap per 3,000 nucleotides. The hnRNA molecules sedimenting from 10S to 28S have one m6Ap per 1,800 nucleotides. Poly(A)+ nuclear RNA is enriched in m6A, containing 1 residue of m6A per 700 to 800 nucleotides, a value close to that obtained for the polyadenylated cytoplasmic RNA. Images PMID:866178

  13. Methyl esters (biodiesel) from and fatty acid profile of Gliricidia sepium seed oil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing the supply of biodiesel by defining and developing additional feedstocks is important to overcome the still limited amounts available of this alternative fuel. In this connection, the methyl esters of the seed oil of Gliricidia sepium were synthesized and the significant fuel-related prop...

  14. Bioconversion of methyl ricinoleate to 4-hydroxy-decanoic acid and to gamma-decalactone by yeasts of the genus Candida.

    PubMed

    Endrizzi, A; Belin, J M

    1995-01-01

    The capacity of several strains of yeasts to do the bioconversion of methyl ricinoleate into gamma-decalactone, was studied in a medium containing this methylic ester of fatty acid as sole carbon source. Amongst the strains which are able to do this bioconversion, two types of behaviour are observed: some of the strains produce gamma-decalactone during all the incubation in bioconversion medium while others produce this aroma compound very quickly and then consume it fast too. The tested strains produce at the same time gamma-decalactone and the corresponding acid form (4-hydroxy-decanoic acid), and this, in variable proportions.

  15. Isolation of betulinic acid, its methyl ester and guaiane sesquiterpenoids with protein tyrosine phosphatase 1B inhibitory activity from the roots of Saussurea lappa C.B.Clarke.

    PubMed

    Choi, Ji Young; Na, Minkyun; Hyun Hwang, In; Ho Lee, Seung; Young Bae, Eun; Yeon Kim, Bo; Seog Ahn, Jong

    2009-01-08

    Activity-guided fractionation of a MeOH extract of the roots of Saussurea lappa C.B.Clarke (Compositae), using an in vitro protein tyrosine phosphatase 1B (PTP1B) inhibition assay, led to the isolation of four active constituents: betulinic acid (1), betulinic acid methyl ester (2), mokko lactone (3) and dehydrocostuslactone (4), along with nine inactive compounds. Our findings indicate that betulinic acid (1) and its methyl ester 2, as well as the two guaiane sesquiterpenoids 3 and 4 are potential lead moieties for the development of new PTP1B inhibitors.

  16. Seed storage protein deficiency improves sulfur amino acid content in common bean (Phaseolus vulgaris L.): redirection of sulfur from gamma-glutamyl-S-methyl-cysteine.

    PubMed

    Taylor, Meghan; Chapman, Ralph; Beyaert, Ronald; Hernández-Sebastià, Cinta; Marsolais, Frédéric

    2008-07-23

    The contents of sulfur amino acids in seeds of common bean ( Phaseolus vulgaris L.) are suboptimal for nutrition. They accumulate large amounts of a gamma-glutamyl dipeptide of S-methyl-cysteine, a nonprotein amino acid that cannot substitute for methionine or cysteine in the diet. Protein accumulation and amino acid composition were characterized in three genetically related lines integrating a progressive deficiency in major seed storage proteins, phaseolin, phytohemagglutinin, and arcelin. Nitrogen, carbon, and sulfur contents were comparable among the three lines. The contents of S-methyl-cysteine and gamma-glutamyl-S-methyl-cysteine were progressively reduced in the mutants. Sulfur was shifted predominantly to the protein cysteine pool, while total methionine was only slightly elevated. Methionine and cystine contents (mg per g protein) were increased by up to ca. 40%, to levels slightly above FAO guidelines on amino acid requirements for human nutrition. These findings may be useful to improve the nutritional quality of common bean.

  17. Complete Genome Sequence of Moraxella osloensis Strain KMC41, a Producer of 4-Methyl-3-Hexenoic Acid, a Major Malodor Compound in Laundry

    PubMed Central

    Hirakawa, Hideki; Morita, Yuji; Tomida, Junko; Sato, Jun; Matsumura, Yuta; Mitani, Asako; Niwano, Yu; Takeuchi, Kohei; Kubota, Hiromi; Kawamura, Yoshiaki

    2016-01-01

    We report the complete genome sequence of Moraxella osloensis strain KMC41, isolated from laundry with malodor. The KMC41 genome comprises a 2,445,556-bp chromosome and three plasmids. A fatty acid desaturase and at least four β-oxidation-related genes putatively associated with 4-methyl-3-hexenoic acid generation were detected in the KMC41 chromosome. PMID:27445387

  18. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  19. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  20. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  1. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  2. 40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with boric acid (H3BO3).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-methyl-ω-hydroxy, ester with...

  3. Aedes aegypti juvenile hormone acid methyl transferase, the ultimate enzyme in the biosynthetic pathway of juvenile hormone III, exhibits substrate control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report on the cloning, sequencing, characterization, 3D modeling and docking of Aedes aegypti juvenile hormone acid methyl transferase (AeaJHAMT), the enzyme that converts juvenile hormone acid (JHA) into juvenile hormone (JH). Purified recombinant AeaJHAMT was extensively characterized for enzym...

  4. Interaction of methylation-related genetic variants with circulating fatty acids on plasma lipids: a meta-analysis of 7 studies and methylation analysis of 3 studies in the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium12

    PubMed Central

    Follis, Jack L; Smith, Caren E; Tanaka, Toshiko; Manichaikul, Ani W; Chu, Audrey Y; Samieri, Cecilia; Zhou, Xia; Guan, Weihua; Wang, Lu; Biggs, Mary L; Chen, Yii-Der I; Hernandez, Dena G; Borecki, Ingrid; Chasman, Daniel I; Rich, Stephen S; Ferrucci, Luigi; Irvin, Marguerite Ryan; Aslibekyan, Stella; Zhi, Degui; Tiwari, Hemant K; Claas, Steven A; Sha, Jin; Kabagambe, Edmond K; Lai, Chao-Qiang; Parnell, Laurence D; Lee, Yu-Chi; Amouyel, Philippe; Lambert, Jean-Charles; Psaty, Bruce M; King, Irena B; Mozaffarian, Dariush; McKnight, Barbara; Bandinelli, Stefania; Tsai, Michael Y; Ridker, Paul M; Ding, Jingzhong; Mstat, Kurt Lohmant; Liu, Yongmei; Sotoodehnia, Nona; Barberger-Gateau, Pascale; Steffen, Lyn M; Siscovick, David S; Absher, Devin; Arnett, Donna K; Ordovás, José M; Lemaitre, Rozenn N

    2016-01-01

    Background: DNA methylation is influenced by diet and single nucleotide polymorphisms (SNPs), and methylation modulates gene expression. Objective: We aimed to explore whether the gene-by-diet interactions on blood lipids act through DNA methylation. Design: We selected 7 SNPs on the basis of predicted relations in fatty acids, methylation, and lipids. We conducted a meta-analysis and a methylation and mediation analysis with the use of data from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium and the ENCODE (Encyclopedia of DNA Elements) consortium. Results: On the basis of the meta-analysis of 7 cohorts in the CHARGE consortium, higher plasma HDL cholesterol was associated with fewer C alleles at ATP-binding cassette subfamily A member 1 (ABCA1) rs2246293 (β = −0.6 mg/dL, P = 0.015) and higher circulating eicosapentaenoic acid (EPA) (β = 3.87 mg/dL, P = 5.62 × 1021). The difference in HDL cholesterol associated with higher circulating EPA was dependent on genotypes at rs2246293, and it was greater for each additional C allele (β = 1.69 mg/dL, P = 0.006). In the GOLDN (Genetics of Lipid Lowering Drugs and Diet Network) study, higher ABCA1 promoter cg14019050 methylation was associated with more C alleles at rs2246293 (β = 8.84%, P = 3.51 × 1018) and lower circulating EPA (β = −1.46%, P = 0.009), and the mean difference in methylation of cg14019050 that was associated with higher EPA was smaller with each additional C allele of rs2246293 (β = −2.83%, P = 0.007). Higher ABCA1 cg14019050 methylation was correlated with lower ABCA1 expression (r = −0.61, P = 0.009) in the ENCODE consortium and lower plasma HDL cholesterol in the GOLDN study (r = −0.12, P = 0.0002). An additional mediation analysis was meta-analyzed across the GOLDN study, Cardiovascular Health Study, and the Multi-Ethnic Study of Atherosclerosis. Compared with the model without the adjustment of cg14019050 methylation, the model with such

  5. Maternal folic acid supplementation modulates DNA methylation and gene expression in the rat offspring in a gestation period-dependent and organ-specific manner.

    PubMed

    Ly, Anna; Ishiguro, Lisa; Kim, Denise; Im, David; Kim, Sung-Eun; Sohn, Kyoung-Jin; Croxford, Ruth; Kim, Young-In

    2016-07-01

    Maternal folic acid supplementation can alter DNA methylation and gene expression in the developing fetus, which may confer disease susceptibility later in life. We determined which gestation period and organ were most sensitive to the modifying effect of folic acid supplementation during pregnancy on DNA methylation and gene expression in the offspring. Pregnant rats were randomized to a control diet throughout pregnancy; folic acid supplementation at 2.5× the control during the 1st, 2nd or 3rd week of gestation only; or folic acid supplementation throughout pregnancy. The brain, liver, kidney and colon from newborn pups were analyzed for folate concentrations, global DNA methylation and gene expression of the Igf2, Er-α, Gr, Ppar-α and Ppar-γ genes. Folic acid supplementation during the 2nd or 3rd week gestation or throughout pregnancy significantly increased brain folate concentrations (P<.001), while only folic acid supplementation throughout pregnancy significantly increased liver folate concentrations (P=.005), in newborn pups. Brain global DNA methylation incrementally decreased from early to late gestational folic acid supplementation and was the lowest with folic acid supplementation throughout pregnancy (P=.026). Folic acid supplementation in late gestation or throughout pregnancy significantly decreased Er-α, Gr and Ppar-α gene expression in the liver (P<.05). The kidney and colon were resistant to the effect of folic acid supplementation. Maternal folic acid supplementation affects tissue folate concentrations, DNA methylation and gene expression in the offspring in a gestation-period-dependent and organ-specific manner.

  6. Application of gas-liquid chromatography and high-performance liquid chromatography to the analysis of trace amounts of salicylic acid, acetylsalicylic anhydride and acetylsalicylsalicylic acid in aspirin samples and aspirin formulations.

    PubMed

    Ali, S L

    1976-11-03

    The gas-liquid chromatographic (GLC) determination of salicylic acid (SA) in 12 commercial acetylsalicylic acid (aspirin, ASA) samples and 12 ASA formulations is reported. The GLC determination of SA as an impurity in ASA, utilising methylation with methyl iodide in the presence of potassium carbonate, requires a column chromatographic separation of SA prior to derivatization. Trace amounts of SA in ASA have also been determined by high-performance liquid chromatography (HPLC) on a Sil-X-I adsorption column using light petroleum-ethyl acetate-acetic acid as the mobile phase. Acetylsalicylic anhydride (ASN) and acetylsalicylsalicylic acid (ASSA) were determined by HPLC on a reversed-phase C18 column with water-methanol mixtures as the mobile phase. GLC was also applied to the determination of ASN as an impurity in ASA formulations.

  7. Synthesis of fatty acid methyl ester from crude jatropha (Jatropha curcas Linnaeus) oil using aluminium oxide modified Mg-Zn heterogeneous catalyst.

    PubMed

    Olutoye, M A; Hameed, B H

    2011-06-01

    The synthesis of fatty acid methyl esters (FAME) as a substitute to petroleum diesel was investigated in this study from crude jatropha oil (CJO), a non-edible, low-cost alternative feedstock, using aluminium modified heterogeneous basic oxide (Mg-Zn) catalyst. The transesterification reaction with methanol to methyl esters yielded 94% in 6h with methanol-oil ratio of 11:1, catalyst loading of 8.68 wt.% at 182°C and the properties of CJO fuel produced were determine and found to be comparable to the standards according to ASTM. In the range of experimental parameters investigated, it showed that the catalyst is selective to production of methyl esters from oil with high free fatty acid (FFA) and water content of 7.23% and 3.28%, respectively in a single stage process. Thus, jatropha oil is a promising feedstock for methyl ester production and large scale cultivation will help to reduce the product cost.

  8. Effect of the Methylation and N-H Acidic Group on the Physicochemical Properties of Imidazolium-Based Ionic Liquids.

    PubMed

    Rodrigues, Ana S M C; Rocha, Marisa A A; Almeida, Hugo F D; Neves, Catarina M S S; Lopes-da-Silva, José A; Freire, Mara G; Coutinho, João A P; Santos, Luís M N B F

    2015-07-16

    This work presents and highlights the differentiation of the physicochemical properties of the [C1Him][NTf2], [C2Him][NTf2], [(1)C1(2)C1Him][NTf2], and [(1)C4(2)C1(3)C1im][NTf2] that is related with the strong bulk interaction potential, which highlights the differentiation on the physicochemical arising from the presence of the acidic group (N-H) as well as the methylation in position 2, C(2), of the imidazolium ring. Densities, viscosities, refractive indices, and surface tensions in a wide range of temperatures, as well as isobaric heat capacities at 298.15 K, for this IL series are presented and discussed. It was found that the volumetric properties are barely affected by the geometric and structural isomerization, following a quite regular trend. A linear correlation between the glass transition temperature, Tg, and the alkyl chain size was found; however, ILs with the acidic N-H group present a significant higher Tg than the [(1)CN-1(3)C1im][NTf2] and [(1)CN(3)CNim][NTf2] series. It was found that the most viscous ILs, ([(1)C1Him][NTf2], [(1)C2Him][NTf2], and [(1)C1(2)C1Him][NTf2]) have an acidic N-H group in the imidazolium ring in agreement with the observed increase of energy barrier of flow. The methylation in position 2, C(2), as well as the N-H acidic group in the imidazolium ring contribute to a significant variation in the cation-anion interactions and their dynamics, which is reflected in their charge distribution and polarizability leading to a significant differentiation of the refractive indices, surface tension, and heat capacities. The observed differentiation of the physicochemical properties of the [(1)C1Him][NTf2], [(1)C2Him][NTf2], [(1)C1(2)C1Him][NTf2], and [(1)C4(2)C1(3)C1im][NTf2] are an indication of the stronger bulk interaction potential, which highlights the effect that arises from the presence of the acidic group (N-H) as well as the methylation in position 2 of the imidazolium ring.

  9. Glycolic Acid Silences Inflammasome Complex Genes, NLRC4 and ASC, by Inducing DNA Methylation in HaCaT Cells.

    PubMed

    Tang, Sheau-Chung; Yeh, Jih-I; Hung, Sung-Jen; Hsiao, Yu-Ping; Liu, Fu-Tong; Yang, Jen-Hung

    2016-03-01

    AHAs (α-hydroxy acids), including glycolic acid (GA), have been widely used in cosmetic products and superficial chemical peels. Inflammasome complex has been shown to play critical roles in inflammatory pathways in human keratinocytes. However, the anti-inflammatory mechanism of GA is still unknown. The aim of this study is to investigate the relationship between the expression of the inflammasome complex and epigenetic modification to elucidate the molecular mechanism of the anti-inflammatory effect of GA in HaCaT cells. We evaluated NLRP3, NLRC4, AIM2, and ASC inflammasome complex gene expression on real-time polymerase chain reaction (PCR). Methylation changes were detected in these genes following treatment with DNA methyltransferase (DNMT) inhibitor 5-aza-2'-deoxycytidine (5-Aza) with or without the addition of GA using methylation-specific PCR (MSP). GA inhibited the expressions of these inflammasome complex genes, and the decreases in the expressions of mRNA were reversed by 5-Aza treatment. Methylation was detected in NLRC4 and ASC on MSP, but not in NLRP3 or AIM2. GA decreased NLRC4 and ASC gene expression by increasing not only DNA methyltransferase 3B (DNMT-3B) protein level, but also total DNMT activity. Furthermore, silencing of DNMT-3B (shDNMT-3B) increased the expressions of NLRC4 and ASC. Our data demonstrated that GA treatment induces hypermethylation of promoters of NLRC4 and ASC genes, which may subsequently lead to the hindering of the assembly of the inflammasome complex in HaCaT cells. These results highlight the anti-inflammatory potential of GA-containing cosmetic agents in human skin cells and demonstrate for the first time the role of aberrant hypermethylation in this process.

  10. Role of glycoconjugates of 3-methyl-4-hydroxyoctanoic acid in the evolution of oak lactone in wine during oak maturation.

    PubMed

    Wilkinson, Kerry L; Prida, Andrei; Hayasaka, Yoji

    2013-05-08

    Oak lactone is a natural component of oak wood, but it also exists in glycoconjugate precursor forms. This study concerned the role of glycoconjugates of 3-methyl-4-hydroxyoctanoic acid, specifically a galloylglucoside, glucoside, and rutinoside, in the evolution of oak lactone during cooperage and maturation. The glycoconjugate profiles of 10 French oak samples were obtained by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using stable isotope dilution analysis. The galloylglucoside was found to be the predominant glycoconjugate precursor and ranged in concentration from 110 to 354 μg/g. Maturation trials indicated the galloylglucoside undergoes acid-catalyzed hydrolysis after extraction into wine; after 12 months of maturation, the glucoside was the most abundant precursor, present at between 2- and 11-fold higher concentrations than those observed for powdered oak. Thermal degradation of glycoconjugates was observed only when oak samples were heated at 200 °C for 30 min, demonstrating their thermal stability.

  11. Crystal growth, vibrational, optical, thermal and theoretical studies of a nonlinear optical material: 2-Methyl 3,5-dinitrobenzoic acid

    NASA Astrophysics Data System (ADS)

    Sangeetha, K.; Guru Prasad, L.; Mathammal, R.

    2016-11-01

    Single crystals of 2-methyl 3,5-dinitro benzoic acid with reasonable size have been grown by slow evaporation solution growth method using ethanol as solvent. Quantum chemical calculation of 2-methyl 3,5-Dinitro benzoic acid was carried out by using DFT/B3LYP/6-31+G(d,p) method. The powder X-ray diffraction pattern was recorded and indexed. Both the experimental and theoretical vibrational spectrum validates the presence of functional groups. Polarizability, first order hyperpolarizability and the electric dipole moment values have been computed theoretically. The 1H and 13C NMR chemical shift of the molecule was calculated and compared with experimental results. TG/DSC analysis has been employed to understand the thermal and physio-chemical stability of the title compound. Frequency conversion property of the crystal was tested by Kurtz and Perry method. Optical absorption behavior of the grown crystal was examined by recording the optical spectrum and band gap energy was also estimated. The calculated HOMO and LUMO energy shows the charge transfer nature of the molecule.

  12. Poly(methacrylic acid-co-methyl methacrylate) beads promote vascularization and wound repair in diabetic mice.

    PubMed

    Martin, Daniel C; Semple, John L; Sefton, Michael V

    2010-05-01

    Topical application of beads made from poly(methacrylic acid-co-methyl methacrylate) (45 mol % methacrylic acid, MAA) increased the number of blood vessels and improved 1.5 x 1.5 cm full thickness wound closure in a diabetic mouse (db/db) model. Three groups were compared: MAA beads, control poly(methyl methacrylate) beads (PMMA), and no bead blanks. MAA bead treatment significantly increased percent wound closure at all timepoints (7, 14, and 21 days) with MAA bead-treated wounds almost closed at day 21 (91 +/- 5.4% MAA vs. 79 +/- 3.2% PMMA or 76 +/- 4.8% no beads; p < 0.05). This was consistent with the expected significant increase in vascularity in the MAA group at days 7 and 14. For example at day 14, MAA bead-treated wounds had a vascular density of 22.7 +/- 2.6 vessels/hpf compared with 17.0 +/- 2.0 vessels/hpf in the PMMA bead group (p < 0.05). Epithelial gap and migration measurements suggested that the increased vascularity leads to enhanced epithelial cell migration as a principal means of wound closure. Although studies are underway to elucidate the mechanism of this angiogenic response, the results presented here support the notion that such materials, perhaps in other forms, may be useful in wound care or in other situations where vascularity is to be enhanced without the use of exogenous growth factors.

  13. Rosmarinic Acid and Its Methyl Ester as Antimicrobial Components of the Hydromethanolic Extract of Hyptis atrorubens Poit. (Lamiaceae)

    PubMed Central

    Abedini, Amin; Roumy, Vincent; Mahieux, Séverine; Biabiany, Murielle; Standaert-Vitse, Annie; Rivière, Céline; Sahpaz, Sevser; Bailleul, François

    2013-01-01

    Primary biological examination of four extracts of the leaves and stems of Hyptis atrorubens Poit. (Lamiaceae), a plant species used as an antimicrobial agent in Guadeloupe, allowed us to select the hydromethanolic extract of the stems for further studies. It was tested against 46 microorganisms in vitro. It was active against 29 microorganisms. The best antibacterial activity was found against bacteria, mostly Gram-positive ones. Bioautography enabled the isolation and identification of four antibacterial compounds from this plant: rosmarinic acid, methyl rosmarinate, isoquercetin, and hyperoside. The MIC and MBC values of these compounds and their combinations were determined against eight pathogenic bacteria. The best inhibitory and bactericidal activity was found for methyl rosmarinate (0.3 mg/mL). Nevertheless, the bactericidal power of rosmarinic acid was much faster in the time kill study. Synergistic effects were found when combining the active compounds. Finally, the inhibitory effects of the compounds were evaluated on the bacterial growth phases at two different temperatures. Our study demonstrated for the first time antimicrobial activity of Hyptis atrorubens with identification of the active compounds. It supports its traditional use in French West Indies. Although its active compounds need to be further evaluated in vivo, this work emphasizes plants as potent sources of new antimicrobial agents when resistance to antibiotics increases dramatically. PMID:24348709

  14. Synthesis and bioevaluation of 2-phenyl-4-methyl-1,3-selenazole-5-carboxylic acids as potent xanthine oxidase inhibitors.

    PubMed

    Guan, Qi; Cheng, Zengjin; Ma, Xiaoxue; Wang, Lijie; Feng, Dongjie; Cui, Yuanhang; Bao, Kai; Wu, Lan; Zhang, Weige

    2014-10-06

    A series of 2-phenyl-4-methyl-1,3-selenazole-5-carboxylic acid derivatives (8a-f, 9a-m) were synthesized and evaluated for inhibitory activity against xanthine oxidase in vitro. Structure-activity relationship analyses have also been presented. Most of the target compounds exhibited potency levels in the nanomolar range. Compound 9e emerged as the most potent xanthine oxidase inhibitor (IC50 = 5.5 nM) in comparison to febuxostat (IC50 = 18.6 nM). Steady-state kinetics measurements with the bovine milk enzyme indicated a mixed type inhibition with Ki and Ki' values of 0.9 and 2.3 nM, respectively. A molecular modeling study on compounds 9e was performed to gain an insight into its binding mode with xanthine oxidase, and to provide the basis for further structure-guided design of new non-purine xanthine oxidase inhibitors related with 2-phenyl-4-methyl-1,3-selenazole-5-carboxylic acid scaffold.

  15. Antinociceptive activity of Paederosidic Acid Methyl Ester (PAME) from the n-butanol fraction of Paederia scandens in mice.

    PubMed

    Chen, Yu-Feng; Huang, Ying; Tang, Wei-Zhong; Qin, Lu-Ping; Zheng, Han-chen

    2009-08-01

    Antinociceptive activity of Paederosidic Acid Methyl Ester (PAME), a chemical compound isolated from the n-butanol fraction of Paederia scandens, was evaluated in mice using chemical and thermal models of nociception. PAME given by intraperitoneal injection at doses of 20, 40 and 60 mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid, subplantar formalin or capsaicin injections and on thermal nociception in the tail-flick test and the hot plate test. In the pentobarbital sodium-induced sleep time test and the open-field test, PAME neither significantly enhanced the pentobarbital sodium-induced sleep time nor impaired the motor performance, indicating that the observed antinociceptive activity of PAME was unlikely due to sedation or motor abnormality. Core body temperature measurement showed that PAME did not affect temperature within a 2-h period. Moreover, PAME-induced antinociception in the hot plate test was insensitive to naloxone or nimodipine but significantly antagonized by L-NAME (N (G)-nitro-L-arginine methyl ester), methylene blue and glibenclamide. These results suggested that PAME-produced antinociception was possibly related to the pathway of NO-cGMP-ATP sensitive K(+) channels, which merited further studies regarding the precise site and mechanisms of action.

  16. Rosmarinic Acid and Its Methyl Ester as Antimicrobial Components of the Hydromethanolic Extract of Hyptis atrorubens Poit. (Lamiaceae).

    PubMed

    Abedini, Amin; Roumy, Vincent; Mahieux, Séverine; Biabiany, Murielle; Standaert-Vitse, Annie; Rivière, Céline; Sahpaz, Sevser; Bailleul, François; Neut, Christel; Hennebelle, Thierry

    2013-01-01

    Primary biological examination of four extracts of the leaves and stems of Hyptis atrorubens Poit. (Lamiaceae), a plant species used as an antimicrobial agent in Guadeloupe, allowed us to select the hydromethanolic extract of the stems for further studies. It was tested against 46 microorganisms in vitro. It was active against 29 microorganisms. The best antibacterial activity was found against bacteria, mostly Gram-positive ones. Bioautography enabled the isolation and identification of four antibacterial compounds from this plant: rosmarinic acid, methyl rosmarinate, isoquercetin, and hyperoside. The MIC and MBC values of these compounds and their combinations were determined against eight pathogenic bacteria. The best inhibitory and bactericidal activity was found for methyl rosmarinate (0.3 mg/mL). Nevertheless, the bactericidal power of rosmarinic acid was much faster in the time kill study. Synergistic effects were found when combining the active compounds. Finally, the inhibitory effects of the compounds were evaluated on the bacterial growth phases at two different temperatures. Our study demonstrated for the first time antimicrobial activity of Hyptis atrorubens with identification of the active compounds. It supports its traditional use in French West Indies. Although its active compounds need to be further evaluated in vivo, this work emphasizes plants as potent sources of new antimicrobial agents when resistance to antibiotics increases dramatically.

  17. Fabrication of calcium phosphate-calcium sulfate injectable bone substitute using hydroxy-propyl-methyl-cellulose and citric acid.

    PubMed

    Thai, Van Viet; Lee, Byong-Taek

    2010-06-01

    In this study, an injectable bone substitute (IBS) consisting of citric acid, chitosan, and hydroxyl propyl methyl cellulose (HPMC) as the liquid phase and tetra calcium phosphate (TTCP), dicalcium phosphate dihydrate (DCPD) and calcium sulfate dehydrate (CSD, CaSO4 x 2H2O) powders as the solid phase, were fabricated. Two groups were classified based on the percent of citric acid in the liquid phase (20, 40 wt%). In each groups, the HPMC percentage was 0, 2, and 4 wt%. An increase in compressive strength due to changes in morphology was confirmed by scanning electron microscopy images. A good conversion rate of HAp at 20% citric acid was observed in the XRD profiles. In addition, HPMC was not obviously affected by apatite formation. However, both HPMC and citric acid increased the compressive strength of IBS. The maximum compressive strength for IBS was with 40% citric acid and 4% HPMC after 14 days of incubation in 100% humidity at 37 degrees C.

  18. Entrapment of methyl parathion hydrolase in cross-linked poly(γ-glutamic acid)/gelatin hydrogel.

    PubMed

    Xie, Jianfei; Zhang, Huiwen; Li, Xu; Shi, Yuanliang

    2014-02-10

    Methyl parathion hydrolase (MPH) is an important enzyme in hydrolyzing toxic organophosphorus (OP) compounds. However, MPH is easily deactivated when subjected to extreme environmental conditions and is difficult to recover from the reaction system for reuse, thereby limiting its practical application. To address these shortcomings, we examined the entrapment of MPH in an environment-friendly, biocompatible and biodegradable cross-linked poly(γ-glutamic acid)/gelatin hydrogel. The cross-linked poly(γ-glutamic acid)/gelatin hydrogels were prepared with different gelatin/poly(γ-glutamic acid) mass ratios using water-soluble carbodiimide as the cross-linking agent. The MPH-entrapped cross-linked poly(γ-glutamic acid)/gelatin hydrogel (CPE-MPH) not only possessed improved thermostability, pH stability, and reusability but also exhibited enhanced efficiency in hydrolyzing OP compounds. Furthermore, CPE-MPH possesses high water-absorbing and water-retaining capabilities. We believe that the cross-linked poly(γ-glutamic acid)/gelatin hydrogels are an attractive carrier for the entrapment of diverse enzymes, affording a new approach for enzyme entrapment.

  19. Dietary effects of mead acid on N-methyl-N-nitrosourea-induced mammary cancers in female Sprague-Dawley rats.

    PubMed

    Kinoshita, Yuichi; Yoshizawa, Katsuhiko; Hamazaki, Kei; Emoto, Yuko; Yuri, Takashi; Yuki, Michiko; Kawashima, Hiroshi; Shikata, Nobuaki; Tsubura, Airo

    2016-01-01

    The effect of mead acid (MA; 5,8,11-eicosatrienoic acid) on the suppression of the development and growth of N-methyl-N-nitrosourea (MNU)-induced mammary cancer in female Sprague-Dawley rats was examined. The MA diet (2.4% MA) or control (CTR) diet (0% MA) was started at 6 weeks of age, MNU was injected intraperitoneally at 7 weeks of age, and the rats were maintained on the respective diets for the whole experimental period (until 19 weeks of age). All induced mammary tumors were luminal A subtype carcinomas (estrogen and progesterone receptor positive and HER2/neu negative). The MA diet significantly suppressed the initiation and promotion phases of mammary carcinogenesis; MA suppressed the development (incidence, 61.5 vs. 100%; multiplicity, 2.1 vs. 4.5) and the growth (final tumor weight, 427.1 vs. 1,796.3 mg) of mammary cancers by suppressing cell proliferation, but not by accelerating cell death. There were evident changes in the major fatty acid composition of n-3, n-6, and n-9 fatty acids in the serum of the MA diet group; there was a significant increase in MA and significant decreases in oleic acid (OA), linoleic acid, arachidonic acid and docosahexaenoic acid. In non-tumorous mammary tissue, there was a significant increase in MA and a significant decrease in OA in the MA diet group. The n-6/n-3 ratios in serum and mammary tissue of the MA diet group were significantly decreased. The MA diet suppressed MNU-induced luminal A mammary cancer by lowering cancer cell proliferation. Therefore, MA may be a chemopreventive and chemotherapeutic agent. In addition to hormone therapy, MA supplementation may be a beneficial chemotherapeutic agent for the luminal A subtype of breast cancer.

  20. Salicylic Acid Regulates Pollen Tip Growth through an NPR3/NPR4-Independent Pathway.

    PubMed

    Rong, Duoyan; Luo, Nan; Mollet, Jean Claude; Liu, Xuanming; Yang, Zhenbiao

    2016-11-07

    Tip growth is a common strategy for the rapid elongation of cells to forage the environment and/or to target to long-distance destinations. In the model tip growth system of Arabidopsis pollen tubes, several small-molecule hormones regulate their elongation, but how these rapidly diffusing molecules control extremely localized growth remains mysterious. Here we show that the interconvertible salicylic acid (SA) and methylated SA (MeSA), well characterized for their roles in plant defense, oppositely regulate Arabidopsis pollen tip growth with SA being inhibitory and MeSA stimulatory. The effect of SA and MeSA was independent of known NPR3/NPR4 SA receptor-mediated signaling pathways. SA inhibited clathrin-mediated endocytosis in pollen tubes associated with an increased accumulation of less stretchable demethylated pectin in the apical wall, whereas MeSA did the opposite. Furthermore, SA and MeSA alter the apical activation of ROP1 GTPase, a key regulator of tip growth in pollen tubes, in an opposite manner. Interestingly, both MeSA methylesterase and SA methyltransferase, which catalyze the interconversion between SA and MeSA, are localized at the apical region of pollen tubes, indicating of the tip-localized production of SA and MeSA and consistent with their effects on the apical cellular activities. These findings suggest that local generation of a highly diffusible signal can regulate polarized cell growth, providing a novel mechanism of cell polarity control apart from the one involving protein and mRNA polarization.

  1. Metabolism of fatty acid in yeast: characterisation of beta-oxidation and ultrastructural changes in the genus Sporidiobolus sp. cultivated on ricinoleic acid methyl ester.

    PubMed

    Feron, Gilles; Blin-Perrin, Caroline; Krasniewski, Isabelle; Mauvais, Geneviève; Lherminier, Jeannine

    2005-09-01

    Cell structure modifications and beta-oxidation induction were monitored in two strains of Sporidiobolus, Sp. Ruinenii and Sp. pararoseus after cultivation on ricinoleic acid methyl ester. Ultrastructural observations of the yeast before and after cultivation on fatty acid esters did not reveal major modifications in Sp. ruinenii. Unexpectedly, in Sp. pararoseus a proliferation of the mitochondrion was observed. After induction, Sp. ruinenii principally exhibited an increase in the activities of acyl-CoA oxidase (ACO), hydroxyacyl-CoA deshydrogenase (HAD), thiolase and catalase. In contrast, Sp. pararoseus lacked ACO and catalase activities, but an increase in acyl-CoA deshydrogenase (ACDH) and enoyl-CoA hydratase (ECH) activity was observed. These data suggest that in Sp. ruinenii, beta-oxidation is preferentially localized in the microbody, whereas in Sp. pararoseus it might be localized in the mitochondria.

  2. Characterization and comparison of methacrylic acid with 2-acrylamido-2-methyl-1-propanesulfonic acid in the preparation of monolithic column for capillary electrochromatography.

    PubMed

    Horiguchi, Daisuke; Ohyama, Kaname; Masunaga, Tomoko; Fujita, Yoshiko; Ali, Marwa Fathy Bakr; Kishikawa, Naoya; Kuroda, Naotaka

    2013-01-01

    Butyl methacrylate (BMA)-ethylene dimethacrylate (EDMA)-methacrylic acid (MAA) and BMA-EDMA-2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) monolithic columns were prepared by varying the percentage of ionic monomers for capillary electrochromatography. Monolithic columns with a higher content of ionic monomers provided better column efficiency, and the performance of BMA-EDMA-MAA monoliths was better than BMA-EDMA-AMPS. To characterize and optimize BMA-EDMA-MAA monoliths, the effects of the content of cross-linker and the total monomer in the polymerization mixture on column performance were also studied. Plate heights of 8.2 µm for the unretained solute (thiourea) and 12.6 µm for the retained solute (naphthalene) were achieved with a monolithic column using 2.5% MAA (Column I).

  3. Gas chromatography/mass spectrometric analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids for verification of the Chemical Weapons Convention.

    PubMed

    Pardasani, Deepak; Gupta, Arvinda K; Palit, Meehir; Shakya, Purushottam; Kanaujia, Pankaj K; Sekhar, K; Dubey, Devendra K

    2005-01-01

    This paper describes the synthesis and gas chromatography/electron ionization mass spectrometric (GC/EI-MS) analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids (DAESAs). These sulfonic acids are important environmental signatures of nerve agent VX and its toxic analogues, hence GC/EI-MS analysis of their methyl esters is of paramount importance for verification of the Chemical Weapons Convention. DAESAs were prepared by condensation of 2-bromoethane sulfonic acid with dialkylamines, and by condensation of dialkylaminoethyl chloride with sodium bisulfite. GC/EI-MS analysis of methyl esters of DAESAs yielded mass spectra; based on these spectra, generalized fragmentation routes are proposed that rationalize most of the characteristic ions.

  4. Effects of ascorbic acid deficiency on methyl mercury dicyandiamide toxicosis in guinea pigs.

    PubMed

    Yamini, B; Sleight, S D

    1984-07-01

    Methylmercury dicyandiamide (MMD) when given intraperitoneally at a dosage of 4 mg/kg of body weight at weekly intervals for 3 weeks resulted in death of guinea pigs fed an ascorbic acid deficient diet. Controls fed an ascorbic acid deficient diet survived during this period as did guinea pigs given MMD and fed an ascorbic acid adequate diet. In a second experiment, guinea pigs fed an ascorbic acid deficient diet containing 22 ppm of MMD died within 26 days and had severe hemorrhagic and ulcerative gastroenteritis and coagulative necrosis of the liver. Ascorbic acid deficient controls died at 34 days. The MMD-containing ascorbic acid adequate diet killed guinea pigs in 150 days. Guinea pigs fed an ascorbic acid deficient diet with 44 ppm of MMD died within 20 days with acute neurologic signs. Pathologic changes were mostly in the gray matter. Guinea pigs fed MMD and a diet with adequate ascorbic acid survived for 38 days whereas the ascorbic acid deficient controls survived for 47 days. Results indicate that ascorbic acid deficiency can be a factor in the location and severity of clinical signs and lesions of MMD.

  5. Raman spectra and structures of 1-methyl-4-(4-diethylaminophenylazo)-pyridinium iodide in neutral and acidic aqueous solutions

    NASA Astrophysics Data System (ADS)

    Iwase, Akitaka; Ueda, Atsushi; Kuwae, Akio; Hanai, Kazuhiko; Kunimoto, Ko-Ki

    2013-09-01

    Fourier transform (FT) and resonance Raman spectra of 1-methyl-4-(4-diethylaminophenylazo)-pyridinium iodide (MDP) and its four deuterated and three 15N stable isotopic compounds have been measured in neutral and acidic aqueous solutions, and the molecular structures have been discussed on the basis of detailed vibrational assignments using the isotope shifts. No Raman band due to the azo Ndbnd N group is observed in a neutral aqueous solution and also in the solid state of MDP; therefore, this finding suggests that double bond character of the azo group becomes weak and, consequently, the structures of both benzene and pyridinium rings are close to that of a quinoid. The Raman and the 15N NMR spectra indicate that the Nβ of the azo group is protonated in an acidic solution of MDP. Comparison of the spectra of the two solutions suggests that the benzene ring has more quinoid character in the acidic than in the neutral solution. The chromophore structures have been revealed in each of the neutral (purple) and the acidic (yellow) solution.

  6. Effects of bis homoallylic and homoallylic hydroxyl substitution on the olefinic 13C resonance shifts in fatty acid methyl esters.

    PubMed

    Pfeffer, P E; Sonnet, P E; Schwartz, D P; Osman, S F; Weisleder, D

    1992-04-01

    Substitution of a hydroxyl group at the bis homoallylic position (OH group located three carbons away from the olefinic carbon) in C18 unsaturated fatty acid esters (FAE) induces a 0.73 +/- 0.05 ppm upfield and a 0.73 +/- 0.06 ppm downfield shift on the delta and epsilon olefinic 13C resonances relative to the unsubstituted FAE, respectively. If the hydroxyl group is located on the carboxyl side of the double bond of the bis homoallylic hydroxy fatty acid esters (BHAHFA), the olefinic resonances are uniformly shifted apart by [formula: see text] where delta delta dbu represents the absolute value of the double bond resonance separation in the unsubstituted FAE and 1.46 ppm is the sum of the absolute values of the delta and epsilon shift parameters. With hydroxyl substitution on the terminal methyl side of the double bond, the olefinic shift separation is equal to [formula: see text] In homoallylic (OH group located two carbons away from the olefinic carbon) substituted FAE the gamma and delta induced hydroxyl shifts for the cis double bond resonances are +3.08 and -4.63 ppm, respectively while the trans double bond parameters are +4.06 and -4.18 ppm, respectively. The double bond resonance separation in homoallylic hydroxy fatty acid esters (HAHFA) can be calculated from the formula [formula: see text] for cis and [formula: see text] for the trans case when the OH substitution is on the carboxyl side of the double bond. Conversely, when the OH resides on the terminal methyl side, the double bond shift separations for cis and trans isomers are [formula: see text] and [formula: see text] respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Effective methylation of phosphonic acids related to chemical warfare agents mediated by trimethyloxonium tetrafluoroborate for their qualitative detection and identification by gas chromatography-mass spectrometry.

    PubMed

    Valdez, Carlos A; Leif, Roald N; Alcaraz, Armando

    2016-08-24

    The effective methylation of phosphonic acids related to chemical warfare agents (CWAs) employing trimethyloxonium tetrafluoroborate (TMO·BF4) for their qualitative detection and identification by gas chromatography-mass spectrometry (GC-MS) is presented. The methylation occurs in rapid fashion (1 h) and can be conveniently carried out at ambient temperature, thus providing a safer alternative to the universally employed diazomethane-based methylation protocols. Optimization of the methylation parameters led us to conclude that methylene chloride was the ideal solvent to carry out the derivatization, and that even though methylated products can be observed surfacing after only 1 h, additional time was not found to be detrimental but beneficial to the process particularly when dealing with analytes at low concentrations (∼10 μg mL(-1)). Due to its insolubility in methylene chloride, TMO·BF4 conveniently settles to the bottom during the reaction and does not produce additional interfering by-products that may further complicate the GC-MS analysis. The method was demonstrated to successfully methylate a variety of Schedule 2 phosphonic acids, including their half esters, resulting in derivatives that were readily detected and identified using the instrument's spectral library. Most importantly, the method was shown to simultaneously methylate a mixture of the organophosphorus-based nerve agent hydrolysis products: pinacolyl methylphosphonate (PMPA), cyclohexyl methylphosphonate (CyMPA) and ethyl methylphosphonate (EMPA) (at a 10 μg mL(-1) concentration each) in a fatty acid ester-rich organic matrix (OPCW-PT-O3) featured in the 38th Organisation for the Prohibition of Chemical Weapons (OPCW) Proficiency Test. In addition, the protocol was found to effectively methylate N,N-diethylamino ethanesulfonic acid and N,N-diisopropylamino ethanesulfonic acid that are products arising from the oxidative degradation of the V-series agents VR and VX respectively. The

  8. The Saccharomyces cerevisiae poly(A)-binding protein is subject to multiple post-translational modifications, including the methylation of glutamic acid.

    PubMed

    Low, Jason K K; Hart-Smith, Gene; Erce, Melissa A; Wilkins, Marc R

    2014-01-10

    Poly(A)-binding protein in mouse and man was recently found to be highly post-translationally modified. Here we analysed an ortholog of this protein, Pab1 from Saccharomyces cerevisiae, to assess the conservation and thus likely importance of these modifications. Pab1 showed the presence of six sites of methylated glutamate, five sites of lysine acetylation, and one phosphorylation of serine. Many modifications on Pab1 showed either complete conservation with those on human or mouse PABPC1, were present on nearby residues and/or were present in the same domain(s). The conservation of methylated glutamate, an unusual modification, was of particular note and suggests a conserved function. Comparison of methylated glutamate sites in human, mouse and yeast poly(A)-binding protein, along with methylation sites catalysed by CheR L-glutamyl protein methyltransferase from Salmonella typhimurium, revealed that the methylation of glutamate preferentially occurs in EE and DE motifs or other small regions of acidic amino acids. The conservation of methylated glutamate in the same protein between mouse, man and yeast suggests the presence of a eukaryotic l-glutamyl protein methyltransferase and that the modification is of functional significance.

  9. L-Altruronic acid formed by epimerization of D-galacturonic acid methyl esters during saponification of citrus pectin.

    PubMed

    Zhan, D; Qiu, F; Mort, A J

    2001-02-15

    While searching for oligosaccharides containing rhamnose residues in the endopolygalacturonase (EPG) digest of saponified citrus pectin, we found several oligomers containing, in addition to galacturonic acid, a sugar previously unreported in pectin. The 1- and 2-D 1H NMR spectra of the oligosaccharides were consistent with the sugar being a uronic acid with its 2- and 3-hydroxyls being axial and 4-hydroxyl being equatorial. MALDI-TOF mass spectrometry indicated that the oligomers consisted solely of uronic acids. Reduction of the uronic acids in the oligosaccharides converted them to galactose and altrose. The altrose was found to be the L enantiomer by comparison of its trimethylsilyl (-)-2-butyl glycosides to those of authentic D-altrose and a racemic mixture. The sugar was not found in oligosaccharides prepared from EPG digestion of citrus pectin deesterified with pectin methylesterase rather than saponification. Thus, it appears that during saponification, a small proportion of the methylesterified galacturonic acid residues in pectins is epimerized at C-5 leading to formation of L-altruronic acid residues.

  10. Gas chromatography with tandem differential mobility spectrometry of fatty acid alkyl esters and the selective detection of methyl linolenate in biodiesels by dual-stage ion filtering.

    PubMed

    Pasupuleti, D; Pierce, K; Eiceman, G A

    2015-11-20

    Alkyl esters of fatty acids (FAAEs) with carbon numbers from 8 to 20 formed protonated monomers and proton bound dimers through atmospheric pressure chemical ionization reactions and these gas ions were characterized for their field dependent mobility coefficients using differential mobility spectrometry (DMS). Separation of ion peaks with a vapor modifier was achieved for ions with masses of 317-1033 Da though the differences in these coefficients and the resolution of ion peaks decreased proportionally with increased ion mass. Differences in dispersion curves were sufficient to isolate ions from specific FAAEs in the effluent of a gas chromatograph by dual stage ion filtering using a tandem DMS detector. Methyl linolenate was isolated from nearby eluting methyl oleate, methyl stearate and methyl linoleate within analysis times of 10s without measureable complications from charge suppression in the ion source or leakage in filtering of ions with close proximity of dispersion behavior.

  11. Double bond localization in minor homoallylic fatty acid methyl esters using acetonitrile chemical ionization tandem mass spectrometry.

    PubMed

    Michaud, Anthony L; Diau, Guan-Yeu; Abril, Reuben; Brenna, J Thomas

    2002-08-15

    Double bond position in natural fatty acids is critical to biochemical properties, however, common instrument-based methods cannot locate double bonds in fatty acid methyl esters (FAME), the predominant analysis form of fatty acids. A recently described mass spectrometry (MS) method for locating double bonds in FAME is reported here for the analysis of minor (<1%) components of real FAME mixtures derived from three natural sources; golden algae (Schizochytrium sp.), primate brain white matter, and transgenic mouse liver. Acetonitrile chemical ionization tandem MS was used to determine double bond positions in 39 FAME, most at concentrations well below 1% of all fatty acid methyl esters. FAME identified in golden algae are 14:1n-6, 14:3n-3, 16:1n-7, 16:2n-6, 16:3n-6, 16:3n-3, 16:4n-3, 18:2n-7, 18:3n-7, 18:3n-8, 18:4n-3, 18:4n-5, 20:3n-7, 20:4n-3, 20:4n-5, 20:4n-7, 20:5n-3, and 22:4n-9. Additional FAME identified in primate brain white matter are 20:1n-7, 20:1n-9, 20:2n-7, 20:2n-9, 22:1n-7, 22:1n-9, 22:1n-13, 22:2n-6, 22:2n-7, 22:2n-9, 22:3n-6, 22:3n-7, 22:3n-9, 22:4n-6, 24:1n-7, 24:1n-9, and 24:4n-6. Additional FAME identified in mouse liver are 26:5n-6, 26:6n-3, 28:5n-6, and 28:6n-3. The primate brain 22:3n-7 and algae 18:4n-5 are novel fatty acids. These results demonstrate the usefulness of the technique for analysis of real samples. Tables are presented to aid in interpretation of acetonitrile CIMS/MS spectra.

  12. Enzymatic synthesis of theanine from glutamic acid γ-methyl ester and ethylamine by immobilized Escherichia coli cells with γ-glutamyltranspeptidase activity.

    PubMed

    Zhang, Fei; Zheng, Qing-Zhong; Jiao, Qing-Cai; Liu, Jun-Zhong; Zhao, Gen-Hai

    2010-11-01

    Theanine (γ-glutamylethylamide) is the main amino acid component in green tea. The demand for theanine in the food and pharmaceutical industries continues to increase because of its special flavour and multiple physiological effects. In this research, an improved method for enzymatic theanine synthesis is reported. An economical substrate, glutamic acid γ-methyl ester, was used in the synthesis catalyzed by immobilized Escherichia coli cells with γ-glutamyltranspeptidase (GGT) activity. The results show that GGT activity with glutamic acid γ-methyl ester as substrate was about 1.2-folds higher than that with glutamine as substrate. Reaction conditions were optimized by using 300 mmol/l glutamic acid γ-methyl ester, 3,000 mmol/l ethylamine, and 0.1 g/ml of immobilized GGT cells at pH 10 and 50°C. Under these conditions, the immobilized cells were continuously used ten times, yielding an average glutamic acid γ-methyl ester to theanine conversion rate of 69.3%. Bead activity did not change significantly the first six times they were used, and the average conversion rate during the first six instances was 87.2%. The immobilized cells exhibited favourable operational stability.

  13. First total synthesis and antileishmanial activity of (Z)-16-methyl-11-heptadecenoic acid, a new marine fatty acid from the sponge Dragmaxia undata

    PubMed Central

    Carballeira, Néstor M.; Montano, Nashbly; Cintrón, Gabriel A.; Márquez, Carmary; Rubio, Celia Fernández; Prada, Christopher Fernández; Balaña-Fouce, Rafael

    2010-01-01

    The first total synthesis for the (Z)-16-methyl-11-heptadecenoic acid, a novel fatty acid from the sponge Dragmaxia undata, was accomplished in seven steps and in a 44% overall yield. The use of (trimethylsilyl)acetylene was key in the synthesis. Based on a previous developed strategy in our laboratory the best synthetic route towards the title compound was first acetylide coupling of (trimethylsilyl)acetylene to the long-chain protected 10-bromo-1-decanol followed by a second acetylide coupling to the short-chain 1-bromo-4-methylpentane, which resulted in higher yields. Complete spectral data is also presented for the first time for this recently discovered fatty acid and the cis double bond stereochemistry of the natural acid was established. The title compound displayed antiprotozoal activity against Leishmania donovani (IC50 = 165.5 ± 23.4 µM) and inhibited the leishmania DNA topoisomerase IB enzyme (LdTopIB) with an IC50 = 62.3 ± 0.7 µM. PMID:21129369

  14. Protonation-dissociation reactions of imazamethabenz-methyl and imazamethabenz-Acid in relation to their soil sorption and abiotic degradation.

    PubMed

    Pintado, Sara; Montoya, Mercedes Ruiz; Mellado, José Miguel Rodríguez

    2009-12-09

    This paper present ultraviolet-visible absorption spectra of imazamethabenz-methyl (IMBM) (mixture of the isomers methyl 6-[(RS)-4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl]-m-toluate, m-imazamethabenz, and methyl 2-[(RS)-4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl]-p-toluate, p-imazamethabenz) and the corresponding carboxylic acid, imazamethabenz-acid (IMBA). The spectral characteristics are determined as functions of the pH. The appreciable absorbance in the visible (or near-ultraviolet) region of the spectra indicates that the natural photolytic degradation is possible. From variations of the maximum absorbances of the bands, the pK values of 3.4 +/- 0.2 and 9.4 +/- 0.2 were obtained for protonation of the imidazol (=N-) nitrogen and dissociation of the NH imidazol nitrogen of IMBM, respectively. For IMBA, the dissociation pK of the carboxylic group is very close to that of the imidazol (=N-) nitrogen, both being close to 3.3. The dissociation pK of the NH imidazol nitrogen for IMBA is 9.6 +/- 0.2. The role of the acid-base reactions on the sorption on soils of these herbicides is discussed.

  15. A mathematical model of the interaction of abscisic acid, ethylene and methyl jasmonate on stomatal closure in plants

    PubMed Central

    Hernandez, Bryan Sapon

    2017-01-01

    Stomatal closure is affected by various stimuli such as light, atmospheric carbon dioxide concentration, humidity and phytohormones. Our research focuses on phytohormones, specifically: abscisic acid (ABA), ethylene (ET) and methyl jasmonate (MeJA) that are responsible for the regulation of several plant processes, especially in guard cell signalling. While several studies show that these three phytohormones cause stomatal closure in plants, only two studies are notable for establishing a mathematical model of guard cell signalling involving phytohormones. Those two studies employed Boolean modelling and mechanistic ordinary differential equations modelling. In this study, we propose a new mathematical model of guard cell transduction network for stomatal closure using continuous logical modelling framework. Results showed how the different components of the network function. Furthermore, the model verified the role of antioxidants in the closure mechanism, and the diminished closure level of stomata with combined ABA-ET stimulus. The analysis was extended to ABA-ET-MeJA crosstalk. PMID:28182683

  16. Biocatalytic Resolution of Rac-α-Ethyl-2-Oxo-Pyrrolidineacetic Acid Methyl Ester by Immobilized Recombinant Bacillus cereus Esterase.

    PubMed

    Zheng, Jian-Yong; Liu, Yin-Yan; Luo, Wei-Feng; Zheng, Ren-Chao; Ying, Xiang-Xian; Wang, Zhao

    2016-04-01

    A new esterase-producing strain (Bacillus cereus WZZ001) which exhibiting high hydrolytic activity and excellent enantioselectivity on rac-α-ethyl-2-oxo-pyrrolidineacetic acid methyl ester (R, S-1) has been isolated from soil sample by our laboratory. In this study, the stereoselective hydrolysis of (R, S-1) was performed using the recombinant Bacillus cereus esterase which expressed in Escherichia coli BL21 (DE3). Under the optimized conditions of pH 8.0, 35 °C, and concentration of substrate 400 mM, a successful enzymatic resolution was achieved with an e.e. s of 99.5 % and conversion of 49 %. Immobilization considerably increased the reusability of the recombinant esterase; the immobilized enzyme showed excellent reusability during 6 cycles of repeated 2 h reactions at 35 °C. Thereby, it makes the recombinant B. cereus esterase a usable biocatalyst for industrial application.

  17. Peak alignment and robust principal component analysis of gas chromatograms of fatty acid methyl esters and volatiles.

    PubMed

    Møller, Stina Frosch; Jørgensen, Bo M

    2007-04-01

    Gas chromatograms of fatty acid methyl esters and of volatile lipid oxidation products from fish lipid extracts are analyzed by multivariate data analysis [principal component analysis (PCA)]. Peak alignment is necessary in order to include all sampled points of the chromatograms in the data set. The ability of robust algorithms to deal with outlier problems, including both sample-wise and element-wise outliers, and the advantages and drawbacks of two robust PCA methods, robust PCA (ROBPCA) and robust singular value decomposition when analysing these GC data were investigated. The results show that the usage of ROPCA is advantageous, compared with traditional PCA, when analysing the entire profile of chromatographic data in cases of sub-optimally aligned data. It also demonstrates how choosing the most robust PCA (sample or element-wise) depends on the type of outliers present in the data set.

  18. Fatty acid methyl ester (FAME) technology for monitoring biological foaming in activated sludge: full scale plant verification.

    PubMed

    Lee, J W; Cha, D K; Kim, I; Son, A; Ahn, K H

    2008-02-01

    Fatty acid methyl ester (FAME) technology was evaluated as a monitoring tool for quantification of Gordonia amarae in activated sludge systems. The fatty acid, 19:1 alcohol, which was identified as a unique fatty acid in G. amarae was not only confirmed to be present in foaming plant samples, but the quantity of the signature peak correlated closely with the degree of foaming. Foaming potential experiment provided a range of critical foaming levels that corresponded to G. amarae population. This range of critical Gordonia levels was correlated to the threshold signature FAME amount. Six full-scale wastewater treatment plants were selected based on a survey to participate in our full-scale study to evaluate the potential application of the FAME technique as the Gordonia monitoring tool. Greater amounts of signature FAME were extracted from the mixed liquor samples obtained from treatment plants experiencing Gordonia foaming problems. The amounts of signature FAME correlated well with the conventional filamentous counting technique. These results demonstrated that the relative abundance of the signature FAMEs can be used to quantitatively monitor the abundance of foam-causing microorganism in activated sludge.

  19. Enantioseparation of aromatic amino acids using CEC monolith with novel chiral selector, N-methacryloyl-L-histidine methyl ester.

    PubMed

    Aydoğan, Cemil; Yılmaz, Fatma; Cimen, Duygu; Uzun, Lokman; Denizli, Adil

    2013-07-01

    A new type of polymethacrylate-based monolithic column with chiral stationary phase was prepared for the enantioseparation of aromatic amino acids, namely D,L-phenylalanine, D,L-tyrosine, and D,L-tryptophan by CEC. The monolithic column was prepared by in situ polymerization of butyl methacrylate (BMA), N-methacryloyl-L-histidine methyl ester (MAH), and ethylene dimethacrylate (EDMA) in the presence of porogens. The porogen mixture included DMF and phosphate buffer. MAH was used as a chiral selector. FTIR spectrum of the polymethacrylate-based monolith showed that MAH was incorporated into the polymeric structure via in situ polymerization. Some experimental parameters including pH, concentration of the mobile phase, and MAH concentration with regard to the chiral CEC separation were investigated. Single enantiomers and enantiomer mixtures of the amino acids were separately injected into the monolithic column. It was observed that L-enantiomers of aromatic amino acids migrated before D-enantiomers. The reversal enantiomer migration order for tryptophan was observed upon changing of pH. Using the chiral monolithic column (100 μm id and 375 μm od), the best chiral separation was performed in 35:65% ACN/phosphate buffer (pH 8.0, 10 mM) with an applied voltage of 12 kV in CEC. SEM images showed that the chiral monolithic column has a continuous polymeric skeleton and large through-pore structure.

  20. Determination of fatty acid methyl esters derived from algae scenedesmus dimorphus biomass by gc-ms with one-step esterification of free fatty acids and transesterification of glycerolipids.

    PubMed

    Avula, Satya Girish Chandra; Belovich, Joanne; Xu, Yan

    2017-03-21

    Algae can synthesize, accumulate and store large amounts of lipids in its cells, which holds immense potential as a renewable source of biodiesel. In this work, we have developed and validated a GC-MS method for quantitation of fatty acids and glycerolipids in forms of fatty acid methyl esters derived from algae biomass. Algae Scenedesmus dimorphus dry mass was pulverized by mortar and pestle, then, extracted by the modified Folch method and fractionated into free fatty acids and glycerolipids on aminopropyl solid-phase extraction cartridges. Fatty acid methyl esters were produced by an optimized one-step esterification of fatty acids and transesterification of glycerolipids with boron trichloride/methanol. The matrix effect, recoveries and stability of fatty acids and glycerolipids in algal matrix were first evaluated by spiking stable isotopes of pentadecanoic-2,2-d2 acid and glyceryl tri(hexadecanoate-2,2-d2 ) as surrogate analytes and tridecanoic-2,2-d2 acid as internal standard into algal matrix prior to sample extraction. Later, the method was validated in terms of lower limits of quantitation, linear calibration ranges, intra- and inter-assay precision and accuracy using tridecanoic-2,2-d2 acid as internal standard. This method developed has been applied to the quantitation of fatty acid methyl esters from free fatty acid and glycerolipid fractions of algae Scenedesmus dimorphus. This article is protected by copyright. All rights reserved.

  1. Deoxyribonucleic acid (DNA) methyltransferase contributes to p16 promoter CpG island methylation in lung adenocarcinoma with smoking.

    PubMed

    Sun, Rongju; Liu, Jiahong; Wang, Bo; Ma, Lingyun; Quan, Xiaojiao; Chu, Zhixiang; Li, Tanshi

    2015-01-01

    In this study, the relationship between CpG island methylation and smoking and DNA methyltransferase in the occurrence and development of lung adenocarcinoma was explored by detecting p16 promoter methylation status. Protein and mRNA levels of p16 were detected by immunohistochemistry and in situ hybridization assays. p16 gene promoter and exon 1 CpG island locus Hap II sites methylation status was analyzed with the methylation-specific PCR. Only 4 of 40 p16-positive cases were detected to methylate on CpG islands with 10% methylating rate whereas 18 of p16-negative cases were methylated up to 36.73% of methylating rate. The methylating rates of both p16-positive and p16-negative groups were significantly different. 17 of 50 cases with smoking from total 89 lung adenocarcinoma cases were detected to methylate on CpG islands while only 5 of the remaining 39 non-smokers to methylate. The difference of the methylating rates in both smokers and non-smokers was significant to suggest the closely association of CpG island methylation of p16 with smoking. Furthermore, p16 promoter CpG islands were detected to methylate in 15 of 35 cases with higher DNA methyltransferase activity whereas only 7 detected to methylate in the remaining 54 cases with lower DNA methyltransferase activity. p16 promoter CpG island methylation likely made p16 expressing silence thus contributed to the tumorigenesis of lung adenocarcinoma. Smoking is likely to promote p16 CpG island methylation or by its effect of the activity and metabolism of DNA methyltransferase 1 (DNMT) on CpG island methylation status.

  2. Accurate and Reliable Quantification of Total Microalgal Fuel Potential as Fatty Acid Methyl Esters by in situ Transesterfication

    SciTech Connect

    Laurens, L. M. L.; Quinn, M.; Van Wychen, S.; Templeton, D. W.; Wolfrum, E. J.

    2012-04-01

    In the context of algal biofuels, lipids, or better aliphatic chains of the fatty acids, are perhaps the most important constituents of algal biomass. Accurate quantification of lipids and their respective fuel yield is crucial for comparison of algal strains and growth conditions and for process monitoring. As an alternative to traditional solvent-based lipid extraction procedures, we have developed a robust whole-biomass in situ transesterification procedure for quantification of algal lipids (as fatty acid methyl esters, FAMEs) that (a) can be carried out on a small scale (using 4-7 mg of biomass), (b) is applicable to a range of different species, (c) consists of a single-step reaction, (d) is robust over a range of different temperature and time combinations, and (e) tolerant to at least 50% water in the biomass. Unlike gravimetric lipid quantification, which can over- or underestimate the lipid content, whole biomass transesterification reflects the true potential fuel yield of algal biomass. We report here on the comparison of the yield of FAMEs by using different catalysts and catalyst combinations, with the acid catalyst HCl providing a consistently high level of conversion of fatty acids with a precision of 1.9% relative standard deviation. We investigate the influence of reaction time, temperature, and biomass water content on the measured FAME content and profile for 4 different samples of algae (replete and deplete Chlorella vulgaris, replete Phaeodactylum tricornutum, and replete Nannochloropsis sp.). We conclude by demonstrating a full mass balance closure of all fatty acids around a traditional lipid extraction process.

  3. Accurate and reliable quantification of total microalgal fuel potential as fatty acid methyl esters by in situ transesterification.

    PubMed

    Laurens, Lieve M L; Quinn, Matthew; Van Wychen, Stefanie; Templeton, David W; Wolfrum, Edward J

    2012-04-01

    In the context of algal biofuels, lipids, or better aliphatic chains of the fatty acids, are perhaps the most important constituents of algal biomass. Accurate quantification of lipids and their respective fuel yield is crucial for comparison of algal strains and growth conditions and for process monitoring. As an alternative to traditional solvent-based lipid extraction procedures, we have developed a robust whole-biomass in situ transesterification procedure for quantification of algal lipids (as fatty acid methyl esters, FAMEs) that (a) can be carried out on a small scale (using 4-7 mg of biomass), (b) is applicable to a range of different species, (c) consists of a single-step reaction, (d) is robust over a range of different temperature and time combinations, and (e) tolerant to at least 50% water in the biomass. Unlike gravimetric lipid quantification, which can over- or underestimate the lipid content, whole biomass transesterification reflects the true potential fuel yield of algal biomass. We report here on the comparison of the yield of FAMEs by using different catalysts and catalyst combinations, with the acid catalyst HCl providing a consistently high level of conversion of fatty acids with a precision of 1.9% relative standard deviation. We investigate the influence of reaction time, temperature, and biomass water content on the measured FAME content and profile for 4 different samples of algae (replete and deplete Chlorella vulgaris, replete Phaeodactylum tricornutum, and replete Nannochloropsis sp.). We conclude by demonstrating a full mass balance closure of all fatty acids around a traditional lipid extraction process.

  4. Layered Calcium Structures of p-Phosphonic Acid O-Methyl-Calix[6]arene

    PubMed Central

    Clark, Thomas E.; Martin, Adam; Makha, Mohamed; Sobolev, Alexandre N.; Su, Dian; Rohrs, Henry W.; Gross, Michael L.; Raston, Colin L.

    2010-01-01

    Hexamethoxy-calix[6]arene has been fully functionalized with p-phosphonic acid groups on the upper rim in 57% yield over three steps, and has been authenticated in the solid state by X-ray diffraction as either a nitrate salt or one of two calcium complexes. The latter differ by the ratio of calcium ions per calixarene, either 3:1 or 4:1. In both structures the coordination sphere of the calcium ions is made up of oxygen atoms from the phosphonic acid groups and from water of crystallization, as part of extended polymeric layers in the extended 3D packing. Hirshfeld surface analysis shows extensive O…H and O…Ca interactions for the phosphonic acid moieties in both calcium structures. MALDI-TOF MS of the hexaphosphonic acid shows nano-arrays consisting of up to a maximum of 28 calixarene units. PMID:20657793

  5. Roles of the methyl and methylene groups of mercapto acids in the photoluminescence efficiency and carrier trapping dynamics of CdTe QDs.

    PubMed

    Chandra Sekhar, M; De, Apurba; Hossain, Sk Saddam; Samanta, Anunay

    2017-01-04

    Surface protection using an appropriate ligand is essential for controlling the size, stability and luminescence properties of the quantum dots (QDs). Though 3-mercaptopropanoic acid (3-MPA) is regarded as the most suitable protecting ligand among the mercapto acids for water soluble CdTe QDs, one receives a different picture from recent studies, which report a much higher luminescence efficiency of 3-mercaptobutyric acid (3-MBA) capped QDs compared with those capped by 3-MPA and attribute the observation to the influence of the side methyl group of mercapto acids. Herein we report the luminescence properties and carrier trapping dynamics of four different, but structurally related mercapto acid capped CdTe QDs prepared using a different method. The results show that these QDs are much more fluorescent than those prepared directly in an aqueous environment and surprisingly, no enhanced luminescence for the QDs capped by mercapto acids containing a side methyl group is observed. Ultrafast pump-probe measurements confirm these results in addition to providing insight into the carrier trapping dynamics of these systems. It is shown that our findings, which appear to be in conflict with the recent literature, can be rationalized and the exact role of the side methyl group of the mercapto acids can be understood by careful analysis of the results taking into consideration the difference in the methods of preparation of the QDs in the two cases.

  6. Control of larval and egg development in Aedes aegypti with Ribonucleic acid interference (RNAi) against juvenile hormone acid methyl transferase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ribonucleic acid interference (RNAi) is a powerful approach for elucidating gene functions in a variety of organisms, including mosquitoes and many other insects. Little has been done, however, to harness this approach in order to control adult and larval mosquitoes. Juvenile hormone (JH) plays a pi...

  7. Purification to homogeneity and partial amino acid sequence of a fragment which includes the methyl acceptor site of the human DNA repair protein for O6-methylguanine.

    PubMed

    Major, G N; Gardner, E J; Carne, A F; Lawley, P D

    1990-03-25

    DNA repair by O6-methylguanine-DNA methyltransferase (O6-MT) is accomplished by removal by the enzyme of the methyl group from premutagenic O6-methylguanine-DNA, thereby restoring native guanine in DNA. The methyl group is transferred to an acceptor site cysteine thiol group in the enzyme, which causes the irreversible inactivation of O6-MT. We detected a variety of different forms of the methylated, inactivated enzyme in crude extracts of human spleen of molecular weights higher and lower than the usually observed 21-24kDa for the human O6-MT. Several apparent fragments of the methylated form of the protein were purified to homogeneity following reaction of partially-purified extract enzyme with O6-[3H-CH3]methylguanine-DNA substrate. One of these fragments yielded amino acid sequence information spanning fifteen residues, which was identified as probably belonging to human methyltransferase by virtue of both its significant sequence homology to three procaryote forms of O6-MT encoded by the ada, ogt (both from E. coli) and dat (B. subtilis) genes, and sequence position of the radiolabelled methyl group which matched the position of the conserved procaryote methyl acceptor site cysteine residue. Statistical prediction of secondary structure indicated good homologies between the human fragment and corresponding regions of the constitutive form of O6-MT in procaryotes (ogt and dat gene products), but not with the inducible ada protein, indicating the possibility that we had obtained partial amino acid sequence for a non-inducible form of the human enzyme. The identity of the fragment sequence as belonging to human methyltransferase was more recently confirmed by comparison with cDNA-derived amino acid sequence from the cloned human O6-MT gene from HeLa cells (1). The two sequences compared well, with only three out of fifteen amino acids being different (and two of them by only one nucleotide in each codon).

  8. Acylated glycosides of hydroxy fatty acid methyl esters generated from the crude resin glycoside (pharbitin) of seeds of Pharbitis nil by treatment with indium(III) chloride in methanol.

    PubMed

    Ono, Masateru; Takigawa, Ayako; Mineno, Tomoko; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ikeda, Tsuyoshi; Fukuda-Teramachi, Emiko; Noda, Naoki; Miyahara, Kazumoto

    2010-11-29

    Treatment of the crude ether-insoluble resin glycoside (convolvulin) from seeds of Pharbitis nil (Pharbitis Semen), called pharbitin, with indium(III) chloride in methanol provided seven oligoglycosides of hydroxy fatty acid methyl esters partially acylated by 2-methyl-3-hydroxybutyric (nilic) and 2S-methylbutyric acids. Their structures were elucidated on the basis of NMR and MS data and chemical conversions.

  9. Demethylation of Methylated Arsenic Species during Generation of Arsanes with Tetrahydridoborate(1-) in Acidic Media.

    PubMed

    Marschner, Karel; Musil, Stanislav; Dědina, Jiří

    2016-06-21

    Demethylation during generation of volatile hydrides (HG), i.e. formation of noncorresponding arsanes from monomethylarsonic acid (MAs(V)), dimethylarsinic acid (DMAs(V)), and trimethylarsine oxide (TMAs(V)O) by the reaction of sodium tetrahydridoborate(1-) (THB) with different acids under analytical conditions, was investigated and characterized. Pronounced demethylation of MAs(V), DMAs(V), and TMAs(V)O was found during the reaction of THB with HCl, H2SO4, and HClO4, while HG from CH3COOH or TRIS buffer after prereduction with l-cysteine resulted in the formation of only the corresponding hydrides. In the case of HNO3 formation of corresponding hydrides was preserved for MAs(V) and DMAs(V) but not for TMAs(V)O. The extent of demethylation strongly depends on concentration of the acid and THB. It can be strongly suppressed in HCl medium by partial hydrolysis of THB with optimal concentration of acid before it reacts with MAs(V), DMAs(V), or TMAs(V)O. It appears that the demethylation is due to the action of specific hydrolytic products of THB (most probably by the first and second one).

  10. Induced production of 1-methoxy-indol-3-ylmethyl glucosinolate by jasmonic acid and methyl jasmonate in sprouts and leaves of pak choi (Brassica rapa ssp. chinensis).

    PubMed

    Wiesner, Melanie; Hanschen, Franziska S; Schreiner, Monika; Glatt, Hansruedi; Zrenner, Rita

    2013-07-18

    Pak choi plants (Brassica rapa ssp. chinensis) were treated with different signaling molecules methyl jasmonate, jasmonic acid, linolenic acid, and methyl salicylate and were analyzed for specific changes in their glucosinolate profile. Glucosinolate levels were quantified using HPLC-DAD-UV, with focus on induction of indole glucosinolates and special emphasis on 1-methoxy-indol-3-ylmethyl glucosinolate. Furthermore, the effects of the different signaling molecules on indole glucosinolate accumulation were analyzed on the level of gene expression using semi-quantitative realtime RT-PCR of selected genes. The treatments with signaling molecules were performed on sprouts and mature leaves to determine ontogenetic differences in glucosinolate accumulation and related gene expression. The highest increase of indole glucosinolate levels, with considerable enhancement of the 1-methoxy-indol-3-ylmethyl glucosinolate content, was achieved with treatments of sprouts and mature leaves with methyl jasmonate and jasmonic acid. This increase was accompanied by increased expression of genes putatively involved in the indole glucosinolate biosynthetic pathway. The high levels of indole glucosinolates enabled the plant to preferentially produce the respective breakdown products after tissue damage. Thus, pak choi plants treated with methyl jasmonate or jasmonic acid, are a valuable tool to analyze the specific protection functions of 1-methoxy-indole-3-carbinole in the plants defense strategy in the future.

  11. Trapping hop looper moths, Hypena humuli Harris (Lepidoptera: Erebidae), in hop yards in Washington State with acetic acid and 3-methyl-1-butanol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hop looper moths, Hypena humuli Harris, in commercial hop yards (Humulus lupulus L.) were captured in traps baited with a combination of acetic acid plus 3-methyl-1-butanol (AAMB). The two chemicals were synergistic in attracting hop looper moths; in a comparison of the lure chemicals, most moths we...

  12. DETERMINATION OF 2-METHYL TETROLS AND 2-METHYLGLYCERIC ACID IN SECONDARY ORGANIC AEROSOL FROM LABORATORY IRRADIATED ISOPRENE/NO X/SO 2/AIR MIXTURES

    EPA Science Inventory

    This presentation addresses recent work performed at EPA to evaluate the potential for the photooxidation of isoprene to produce secondary organic aerosol. Analysis of the samples for methyl tetrols and 2-methylglyceric acid were performed at EPA and the University of Antwerp. T...

  13. Acylated Glycosidic Acid Methyl Esters Generated from the Convolvulin Fraction of Rhizoma Jalapae Braziliensis by Treatment with Indium(III) Chloride in Methanol.

    PubMed

    Ono, Masateru; Oda, Satoko; Yasuda, Shin; Mineno, Tomoko; Okawa, Masafumi; Kinjo, Junei; Miyashita, Hiroyuki; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Miyahara, Kazumoto

    2017-01-01

    Four hexaglycosides of methyl 3S,12S-dihydroxyhexadecanoate (1-4) were provided after treatment of the crude convolvulin fraction from Rhizoma Jalapae Braziliensis (the root of Ipomoea operculata (GOMES) MART., Convolvulaceae) with indium(III) chloride in methanol. The structures of 1-4 were elucidated on the basis of spectroscopic and chemical methods. Their sugar moieties were partially acylated with organic acids including (3S,9R)-3,6:6,9-diepoxydecanoic (exogonic) acid, (E)-2-methylbut-2-enoic (tiglic) acid, and isovaleric acid.

  14. Standard enthalpies of formation of perfluoro(2-methyl-3-oxa)hexanoic and perfluoro(2,5-dimethyl-3,6-dioxa)nonanoic acids

    NASA Astrophysics Data System (ADS)

    Lukyanova, V. A.; Papina, T. S.

    2013-02-01

    The energies of combustion of perfluoro(2-methyl-3-oxa)hexanoic and perfluoro(2,5-dimethyl-3,6-dioxa)nonanoic acids are for the first time measured in a calorimeter with a rotating platinized bomb and used to calculate the standard enthalpies of formation of these compounds in the liquid state. Based on the enthalpies of formation, the contribution from the [-CF2OCF(CF3)-] group to the enthalpies of formation of perfluoro acids is calculated.

  15. 40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). (a) Chemical substance and significant new... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). 721.1550 Section 721.1550 Protection of...

  16. 40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). (a) Chemical substance and significant new... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). 721.1550 Section 721.1550 Protection of...

  17. 40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). (a) Chemical substance and significant new... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). 721.1550 Section 721.1550 Protection of...

  18. 40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). (a) Chemical substance and significant new... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). 721.1550 Section 721.1550 Protection of...

  19. 40 CFR 721.1550 - Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). (a) Chemical substance and significant new... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzenediazonium, 4-(di-methyl-amino)-, salt with 2-hy-droxy-5-sul-fo-benzoic acid (1:1). 721.1550 Section 721.1550 Protection of...

  20. Determination of methyl-, 2-hydroxyethyl- and 2-cyanoethylmercapturic acids as biomarkers of exposure to alkylating agents in cigarette smoke.

    PubMed

    Scherer, Gerhard; Urban, Michael; Hagedorn, Heinz-Werner; Serafin, Richard; Feng, Shixia; Kapur, Sunil; Muhammad, Raheema; Jin, Yan; Sarkar, Mohamadi; Roethig, Hans-Juergen

    2010-10-01

    Alkylating agents occur in the environment and are formed endogenously. Tobacco smoke contains a variety of alkylating agents or precursors including, among others, N-nitrosodimethylamine (NDMA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), acrylonitrile and ethylene oxide. We developed and validated a method for the simultaneous determination of methylmercapturic acid (MMA, biomarker for methylating agents such as NDMA and NNK), 2-hydroxyethylmercapturic acid (HEMA, biomarker for ethylene oxide) and 2-cyanoethylmercapturic acid (CEMA, biomarker for acrylonitrile) in human urine using deuterated internal standards of each compound. The method involves liquid/liquid extraction of the urine sample, solid phase extraction on anion exchange cartridges, derivatization with pentafluorobenzyl bromide (PFBBr), liquid/liquid extraction of the reaction mixture and LC-MS/MS analysis with positive electrospray ionization. The method was linear in the ranges of 5.00-600, 1.00-50.0 and 1.50-900 ng/ml for MMA, HEMA and CEMA, respectively. The method was applied to two clinical studies in adult smokers of conventional cigarettes who either continued smoking conventional cigarettes, were switched to test cigarettes consisting of either an electrically heated cigarette smoking system (EHCSS) or having a highly activated carbon granule filter that were shown to have reduced exposure to specific smoke constituents, or stopped smoking. Urinary excretion of MMA was found to be unaffected by switching to the test cigarettes or stop smoking. Urinary HEMA excretion decreased by 46 to 54% after switching to test cigarettes and by approximately 74% when stopping smoking. Urinary CEMA excretion decreased by 74-77% when switching to test cigarettes and by approximately 90% when stopping smoking. This validated method for urinary alkylmercapturic acids is suitable to distinguish differences in exposure not only between smokers and nonsmokers but also between smoking of conventional and

  1. Monitoring of acid-base status of workers at a methyl methacrylate and polymethyl methacrylate production plant in Bulgaria.

    PubMed

    Prakova, Gospodinka R

    2003-01-01

    This study was carried out on 104 workers at three work operations and a control (nonproduction) area, within a methyl methacrylate (MMA)/polymethyl methacrylate (PMMA) production facility in Bulgaria. Airborne monitoring was conducted over a 10-year period for MMA and the reactant chemicals methanol and acetone cyanhydrine at the MMA operation, and MMA was monitored at the PMMA operation. Acid-base status of the workers was evaluated using traditional criteria (pH, pCO(2), pO(2), and HCO(3) in plasma). Data from retrospective monitoring of air levels of the chemicals were compared with the acid-base status of workers at the plant. In some cases air concentrations exceeded the threshold limit value, with the highest percentage of overexposure occurring with airborne MMA in the PMMA production operation. Acid-base disruption indicated by reductions in plasma pH and HCO(3) was found for all groups except the control population. The highest percentage reduction was associated with PMMA production workers. Additionally, respiratory acidosis, indicated by increased pCO(2), was noted in the MMA production and maintenance groups, implying that the response to MMA exposure may involve both the metabolic and respiratory acidosis component. This study was unique in that the combined exposure to MMA and the precursor chemical (methanol) were shown to produce the same effects in workers. It is suggested that when combined exposure occurs, disruption of acid-base status may occur. Enforcement of PPM requirements for coveralls and gloves should prevent skin contamination. Additionally, improvement of equipment in MMA and PMMA production areas is recommended: (1) automation of some manual operations; (2) use of respiratory protection during equipment cleaning; and (3) installation of local ventilation when applicable.

  2. Determining the fatty acid composition in plasma and tissues as fatty acid methyl esters using gas chromatography – a comparison of different derivatization and extraction procedures.

    PubMed

    Ostermann, Annika I; Müller, Maike; Willenberg, Ina; Schebb, Nils Helge

    2014-12-01

    Analysis of the fatty acid (FA) composition in biological samples is commonly carried out using gas liquid chromatography (GC) after transesterification to volatile FA methyl esters (FAME). We compared the efficacy of six frequently used protocols for derivatization of different lipid classes as well as for plasma and tissue samples. Transesterification with trimethylsulfonium hydroxide (TMSH) led to insufficient derivatization efficacies for polyunsaturated FAs (PUFA, <50%). Derivatization in presence of potassium hydroxide (KOH) failed at derivatizing free FAs (FFAs). Boron trifluoride (BF3) 7% in hexane/MeOH (1:1) was insufficient for the transesterification of cholesterol ester (CE) as well as triacylglycerols (TGs). In contrast, methanolic hydrochloric acid (HCl) as well as a combination of BF3 with methanolic sodium hydroxide (NaOH+BF3) were suitable for the derivatization of FFAs, polar lipids, TGs, and CEs (derivatization rate >80% for all tested lipids). Regarding plasma samples, all methods led to an overall similar relative FA pattern. However, significant differences were observed, for example, for the relative amount of EPA+DHA (n3-index). Absolute FA plasma concentrations differed considerably among the methods, with low yields for KOH and BF3. We also demonstrate that lipid extraction with tert-butyl methyl ether/methanol (MTBE/MeOH) is as efficient as the classical method according to Bligh and Dyer, making it possible to replace (environmentally) toxic chloroform.We conclude that HCl-catalyzed derivatization in combination with MeOH/MTBE extraction is the most appropriate among the methods tested for the analysis of FA concentrations and FA pattern in small biological samples. A detailed protocol for the analysis of plasma and tissues is included in this article.

  3. SYNTHESIS AND IN VITRO CHARACTERIZATION OF HYDROXYPROPYL METHYLCELLULOSE-GRAFT-POLY (ACRYLIC ACID/2-ACRYLAMIDO-2-METHYL-1-PROPANESULFONIC ACID) POLYMERIC NETWORK FOR CONTROLLED RELEASE OF CAPTOPRIL.

    PubMed

    Furqan Muhammad, Iqbal; Mahmood, Ahmad; Aysha, Rashid

    2016-01-01

    A super-absorbent hydrogel was developed by crosslinking of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and acrylic acid with hydroxypropyl methylcellulose (HPMC) for controlled release drug delivery of captopril, a well known antihypertensive drug. Acrylic acid and AMPS were polymerized and crosslinked with HPMC by free radical polymerization, a widely used chemical crosslinking method. N,N'-methylenebisacrylamide (MBA) and potassium persulfate (KPS) were added as cross-linker and initiator, respectively. The hydrogel formulation was loaded with captopril (as model drug). The concentration of captopril was monitored at 205 nm using UV spectrophotometer. Equilibrium swelling ratio was determined at pH 2, 4.5 and 7.4 to evaluate the pH responsiveness of the formed hydrogel. The super-absorbent hydrogels were evaluated by FTIR, SEM, XRD, and thermal analysis (DSC and TGA). The formation of new copolymeric network was determined by FTIR, XRD, TGA and DSC analysis. The hydrogel formulations with acrylic acid and AMPS ratio of 4: 1 and lower amounts of crosslinker had shown maximum swelling. Moreover, higher release rate of captopril was observed at pH 7.4 than at pH 2, because of more swelling capacity of copolymer with increasing pH of the aqueous medium. The present research work confirms the development of a stable hydrogel comprising of HPMC with acrylic acid and AMPS. The prepared hydrogels exhibited pH sensitive behav-ior. This superabsorbent composite prepared could be a successful drug carrier for treating hypertension.

  4. 2-(2-Methyl-benzo-yl)benzoic acid: catemeric hydrogen bonding in a γ-keto acid.

    PubMed

    Platosz, Natalia A; Lalancette, Roger A; Thompson, Hugh W; Newman, Jacob M; Schachter, Ari

    2013-01-01

    The crystal structure of the title compound, C15H12O3, displays catemeric aggregation involving O-H⋯O hydrogen bonds progressing from the carboxyl group of one mol-ecule to the ketone O atom of another glide-related neighbor. The mol-ecule is twisted, with the toluene 80.61 (3)° out of plane with respect to the phenyl group of the benzoic acid. The acid group makes a dihedral angle of 13.79 (14)° with the attached phenyl ring. The mol-ecules are achiral, but the space group glide planes create alternating conformational chirality in the chain units. The four hydrogen-bonding chains progress along [001] in an A-A-B-B pattern (right-to-left versus left-to-right), and are related to each other by the center of symmetry at (0.5, 0.5, 0.5) in the chosen cell. There is one close contact (2.54 Å) between a phenyl H atom and the acid carbonyl from a symmetry-related mol-ecule.

  5. Fatty acid profile of seashore mallow (Kosteletzkya pentacarpos) seed oil and properties of the methyl esters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent literature, seashore mallow (Kosteletzkya pentacarpos; also known previously as Kosteletzkya virginica) seed oil was reported as a potential alternative feedstock for biodiesel. In the present work, the fatty acid profile of K. pentacarpos is shown to correspond to that of other plants in ...

  6. Fatty acid methyl esters with two vicinal alkylthio side chains and their NMR characterization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The addition reaction of dimethyl disulfide (DMDS) to double bonds in alkenes and monounsaturated fatty acid esters in the presence of iodine or other catalysts to give bis(methylthio) derivatives has largely served analytical purposes in mass spectrometry with scattered reports on the addition of o...

  7. 2′-O-Methyl RNA/Ethylene-Bridged Nucleic Acid Chimera Antisense Oligonucleotides to Induce Dystrophin Exon 45 Skipping

    PubMed Central

    Lee, Tomoko; Awano, Hiroyuki; Yagi, Mariko; Matsumoto, Masaaki; Watanabe, Nobuaki; Goda, Ryoya; Koizumi, Makoto; Takeshima, Yasuhiro; Matsuo, Masafumi

    2017-01-01

    Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disease characterized by dystrophin deficiency from mutations in the dystrophin gene. Antisense oligonucleotide (AO)-mediated exon skipping targets restoration of the dystrophin reading frame to allow production of an internally deleted dystrophin protein with functional benefit for DMD patients who have out-of-frame deletions. After accelerated US approval of eteplirsen (Exondys 51), which targets dystrophin exon 51 for skipping, efforts are now focused on targeting other exons. For improved clinical benefits, this strategy requires more studies of the delivery method and modification of nucleic acids. We studied a nucleotide with a 2′-O,4′-C-ethylene-bridged nucleic acid (ENA), which shows high nuclease resistance and high affinity for complementary RNA strands. Here, we describe the process of developing a 2′-O-methyl RNA(2′-OMeRNA)/ENA chimera AO to induce dystrophin exon 45 skipping. One 18-mer 2′-OMeRNA/ENA chimera (AO85) had the most potent activity for inducing exon 45 skipping in cultured myotubes. AO85 was administered to mdx mice without significant side effects. AO85 transfection into cultured myotubes from 13 DMD patients induced exon 45 skipping in all samples at different levels and dystrophin expression in 11 patients. These results suggest the possible efficacy of AO-mediated exon skipping changes in individual patients and highlight the 2′-OMeRNA/ENA chimera AO as a potential fundamental treatment for DMD. PMID:28208626

  8. Arachidonic acid supplementation does not affect N-methyl-N-nitrosourea-induced renal preneoplastic lesions in young Lewis rats.

    PubMed

    Yoshizawa, Katsuhiko; Emoto, Yuko; Kinoshita, Yuichi; Kimura, Ayako; Uehara, Norihisa; Yuri, Takashi; Shikata, Nobuaki; Hamazaki, Tomohito; Tsubura, Airo

    2013-04-01

    Arachidonic acid (AA) is naturally found in human breast milk. AA, together with docosahexaenoic acid, is commonly added as a functional food ingredient to commercial infant formula worldwide, in accordance with the international standards of Codex Alimentarius. However, few studies of the possible renal carcinogenic effects of AA supplementation during neonatal life have been performed. The effect of dietary AA supplementation in dams during gestation and lactation was investigated on N-methyl-N-nitrosourea (MNU)-induced preneoplastic lesions in the kidneys of young Lewis rats. Dams were fed a 2.0% AA diet or a basal diet (<0.01% AA). At birth (postnatal day 0), male and female pups received a single intraperitoneal injection of 35 mg/kg MNU or vehicle. Renal morphology was examined after 7, 14, 21, 28 and 60 days. Histopathologically, renal preneoplastic lesions, such as nephroblastomatosis and mesenchymal cell proliferation, were found on day 60 in both the MNU-treated groups. There was no significant difference in lesion incidence of 38% in the basal diet group and 31% in the AA diet group. In conclusion, an AA-rich diet for dams during gestation and lactation does not modify MNU-induced renal preneoplastic lesions in their offspring.

  9. Control of larval and egg development in Aedes aegypti with RNA interference against juvenile hormone acid methyl transferase.

    PubMed

    Van Ekert, Evelien; Powell, Charles A; Shatters, Robert G; Borovsky, Dov

    2014-11-01

    RNA interference (RNAi) is a powerful approach for elucidating gene functions in a variety of organisms, including mosquitoes and many other insects. Little has been done, however, to harness this approach in order to control adult and larval mosquitoes. Juvenile hormone (JH) plays a pivotal role in the control of reproduction in adults and metamorphism in larval mosquitoes. This report describes an approach to control Aedes aegypti using RNAi against JH acid methyl transferase (AeaJHAMT), the ultimate enzyme in the biosynthetic pathway of JH III that converts JH acid III (JHA III) into JH III. In female A. aegypti that were injected or fed jmtA dsRNA targeting the AeaJHAMT gene (jmtA) transcript, egg development was inhibited in 50% of the treated females. In mosquito larvae that were fed transgenic Pichia pastoris cells expressing long hair pin (LHP) RNA, adult eclosion was delayed by 3 weeks causing high mortality. Northern blot analyses and qPCR studies show that jmtA dsRNA causes inhibition of jmtA transcript in adults and larvae, which is consistent with the observed inhibition of egg maturation and larval development. Taken together, these results suggest that jmtA LHP RNA expressed in heat inactivated genetically modified P. pastoris cells could be used to control mosquito populations in the marsh.

  10. The antiallodynic action target of intrathecal gabapentin: Ca2+ channels, KATP channels or N-methyl-d-aspartic acid receptors?

    PubMed

    Cheng, Jen-Kun; Chen, Chien-Chuan; Yang, Jia-Rung; Chiou, Lih-Chu

    2006-01-01

    Gabapentin is a novel analgesic whose mechanism of action is not known. We investigated in a postoperative pain model whether adenosine triphosphate (ATP)-sensitive K+ (K(ATP)) channels, N-methyl-d-aspartic acid (NMDA) receptors, and Ca2+ channels are involved in the antiallodynic effect of intrathecal gabapentin. Mechanical allodynia was induced by a paw incision in isoflurane-anesthetized rats. Withdrawal thresholds to von Frey filament stimulation near the incision site were measured before and after incision and after intrathecal drug administration. The antiallodynic effect of gabapentin (100 mug) was not affected by intrathecal pretreatment with antagonists of K(ATP) channels, NMDA receptors or gamma-aminobutyric acid (GABA)(A) receptors. K(ATP) channel openers and GABA(A) receptor agonist, per se, had little effect on the postincision allodynic response. The Ca2+ channel blocker of N-type (omega-conotoxin GVIA, 0.1-3 microg), but not of P/Q-type (omega-agatoxin IVA), L-type (verapamil, diltiazem or nimodipine), or T-type (mibefradil), attenuated the incision-induced allodynia, as did gabapentin. Both the antiallodynic effects of gabapentin and omega-conotoxin GVIA were attenuated by Bay K 8644, an L-type Ca2+ channel activator. These results provide correlative evidence to support the contention that N-type Ca2+ channels, but not K(ATP) channels or NMDA or GABA(A) receptors, might be involved in the antiallodynic effect of intrathecal gabapentin.

  11. Methyl-inositol, γ-aminobutyric acid and other health benefit compounds in the aril of litchi.

    PubMed

    Wu, Zi-Chen; Yang, Zhuan-Ying; Li, Jian-Guo; Chen, Hou-Bin; Huang, Xu-Ming; Wang, Hui-Cong

    2016-11-01

    The available components in the flesh of litchi seem insufficient to interpret its wide and significant physiological effects. Some unusual compounds, including myo-inositol, inositol methyl derivatives and γ-aminobutyric acid (GABA) were identified as main constituents in the flesh of litchi. Their concentrations varied among cultivars but remain relatively constant during development. Litchi flesh was shown to contain moderate myo-inositol (0.28-0.78 mg g(-1) FW), ascorbic acid (0.08-0.39 mg g(-1) FW) and phenolics (0.47-1.60 mg g(-1) FW), but abundant l-quebrachitol (1.6-6.4 mg g(-1) FW) and GABA (1.7-3.5 mg g(-1) FW). The concentration of GABA in the flesh of litchi was about 100 times higher than in other fruits. And l-quebrachitol is not a common component in fruits. The biological and physiological activities of inositols, inositol derivatives and GABA have been extensively documented. These compounds are probably important compositional characteristic contributing to the widely shown health benefits of litchi.

  12. Bis­(2-amino-5-methyl­pyridinium) fumarate–fumaric acid (1/1)

    PubMed Central

    Hemamalini, Madhukar; Fun, Hoong-Kun

    2010-01-01

    In the crystal structure of the title compound, C6H9N2 +·0.5C4H2O4 2−·0.5C4H6O4, the fumarate dianion and fumaric acid mol­ecule are located on inversion centres. The 2-amino-5-methyl­pyrimidinium cation inter­acts with the carboxyl­ate group of the fumarate anion through a pair of N—H⋯O hydrogen bonds, forming an R 2 2(8) ring motif. These motifs are centrosymmetrically paired via N—H⋯O hydrogen bonds, forming a complementary DDAA array. The carboxyl groups of the fumaric acid mol­ecules and the carboxyl­ate groups of the fumarate anions are hydrogen bonded through O—H⋯O hydrogen bonds, leading to a supra­molecular chain along [101]. The crystal structure is further stabilized by weak C—H⋯O hydrogen bonds. PMID:21588388

  13. Methyl sterol and cyclopropane fatty acid composition of Methylococcus capsulatus grown at low oxygen tensions

    NASA Technical Reports Server (NTRS)

    Jahnke, L. L.; Nichols, P. D.

    1986-01-01

    The sterol and fatty acid concentrations for M. capsulatus grown in fed-batch cultures over a wide range of oxygen tensions (0.1-10.6 percent) and at a constant methane level are evaluated. The analyses reveal that the biomass decreases as oxygen levels are lowered; the sterol concentration increases when the oxygen range is between 0.5-1.1 percent and decreases when the oxygen range is below 0.5 percent; and the amount of monounsaturated C16 decreases and the concentration of cyclopropane fatty acids increases after oxygen is reduced. It is noted that growth and membrane synthesis occur at low oxygen concentrations and that the synthesis of membrane lipids responds to growth conditions.

  14. Acid-base properties, deactivation, and in situ regeneration of condensation catalysts for synthesis of methyl methacrylate

    SciTech Connect

    Gogate, M.R.; Spivey, J.J.; Zoeller, J.R.

    1996-12-31

    Condensation reaction of a propionate with formaldehyde is a novel route for synthesis of methyl methacrylate (MMA). The reaction mechanism involves a proton abstraction from the propionate on the basic sites and activation of the aliphatic aldehyde on the acidic sites of the catalyst. The acid-base properties of ternary V-Si-P oxide catalysts and their relation to the NWA yield in the vapor phase condensation of formaldehyde with propionic anhydride has been studied for the first time. Five different V-Si-P catalysts with different atomic ratios of vanadium, silicon, and phosphorous were synthesized, characterized, and tested in a fixed-bed microreactor system. A V-Si-P 1:10:2.8 catalyst gave the maximum condensation yield of 56% based on HCHO fed at 300{degrees}C and 2 atm and at a space velocity of 290 cc/g cat{center_dot}h. A parameter called the ``q-ratio`` has been defined to correlate the condensation yields to the acid-base properties. The correlation of q-ratio with the condensation yield shows that higher q-ratios are more desirable. The long-term deactivation studies on the V-Si-P 1: 10:2.8 catalyst at 300{degrees}C and 2 atm and at a space velocity of 290 cc/g cat{center_dot}h show that the catalyst activity drops by a factor of nearly 20 over a 180 h period. The activity can be restored to about 78% of the initial activity by a mild oxidative regeneration at 300{degrees}C and 2 atm. The performance of V-Si-P catalyst has been compared to a Ta/SiO{sub 2} catalyst. The Ta- catalyst is more stable and has a higher on-stream catalyst life.

  15. Apelin-36 is protective against N-methyl-D-aspartic-acid-induced retinal ganglion cell death in the mice.

    PubMed

    Sakamoto, Kenji; Murakami, Yuta; Sawada, Shohei; Ushikubo, Hiroko; Mori, Asami; Nakahara, Tsutomu; Ishii, Kunio

    2016-11-15

    Retinal ganglion cell death in glaucoma is caused at least in part by a large Ca(2+) influx through N-methyl-D-aspartic acid (NMDA) receptors. Apelin is a peptide originally found in the tissue extracts of bovine stomach. Recent studies have been shown that apelin protects against the ischemic-reperfused injury in the brain. We examined whether apelin had protective effects on the NMDA-induced retinal ganglion cell (RGC) death using B6.Cg-TgN(Thy1-CFP)23Jrs/J transgenic mice, which express the enhanced cyan fluorescent protein in RGCs in the retina, in vivo. The mice were anesthetized by ketamine and xylazine, and NMDA (40 nmol/eye) was intravitreally injected. We evaluated the effects of apelin-13, [Glp(1)]-apelin-13, a potent agonist of apelin receptor, and apelin-36 on the NMDA-induced retinal ganglion cell death. NMDA-induced retinal ganglion cell loss was clearly seen 7 days after NMDA injection. Intravitreal apelin-36 (0.33 nmol/eye), but not apelin-13 (1 nmol/eye) nor [Glp(1)]-apelin-13 (1 nmol/eye), simultaneously injected with NMDA significantly reduced the cell loss. The protective effect of apelin-36 was not reduced by ML221 (0.1 nmol/eye; 5-[(4-Nitrobenzoyl)oxy]-2-[(2-pyrimidinylthio)methyl]-4H-pyran-4-one), an apelin receptor antagonist, GF109203X (0.03 nmol/eye), a protein kinase C inhibitor, U0126 (0.2 nmol/eye), a MAPK/ERK kinase inhibitor, LY294002 (0.1 nmol/eye), a phosphoinositide 3-kinase inhibitor, Akti 1/2 (0.05 nmol/eye), an Akt inhibitor, or 4,5,6,7-tetrabromobenzotriazole (0.2 nmol/eye), a casein kinase-2 inhibitor. In addition, human apelin-36 did not affect the kainic-acid (20 nmol/eye)-induced ganglion cell death. The present study suggests that apelin-36 protects against the NMDA-induced ganglion cell death independently of the activation of apelin receptor in the murine retina in vivo.

  16. EXTENDED FEAR CONDITIONING REVEALS A ROLE FOR BOTH N-METHYL-d-ASPARTIC ACID AND NON-N-METHYL-d-ASPARTIC ACID RECEPTORS IN THE AMYGDALA IN THE ACQUISITION OF CONDITIONED FEAR

    PubMed Central

    PISTELL, P. J.; FALLS, W. A.

    2009-01-01

    Pavlovian conditioning is a useful tool for elucidating the neural mechanisms involved with learning and memory, especially in regard to the stimuli associated with aversive events. The amygdala has been repeatedly implicated as playing a significant role in the acquisition and expression of fear. If the amygdala is critical for the acquisition of fear, then it should contribute to this processes regardless of the parameters used to induce or evaluate conditioned fear. A series of experiments using reversible inactivation techniques evaluated the role of the amygdala in the acquisition of conditioned fear when training was conducted over several days in rats. Fear-potentiated startle was used to evaluate the acquisition of conditioned fear. Pretraining infusions of N-methyl-d-aspartic acid (NMDA) or non-NMDA receptor antagonists alone into the amygdala interfered with the acquisition of fear early in training, but not later. Pretraining infusions of a cocktail consisting of both an NMDA and non-NMDA antagonist interfered with the acquisition of conditioned fear across all days of training. Taken together these results suggest the amygdala may potentially be critical for the acquisition of conditioned fear regardless of the parameters utilized. PMID:18675886

  17. Mead acid supplementation does not rescue rats from cataract and retinal degeneration induced by N-methyl-N-nitrosourea.

    PubMed

    Emoto, Yuko; Yoshizawa, Katsuhiko; Hamazaki, Kei; Kinoshita, Yuichi; Yuki, Michiko; Yuri, Takashi; Kawashima, Hiroshi; Tsubura, Airo

    2015-01-01

    Fatty acids and their derivatives play a role in the response to ocular disease. Our current study investigated the effects of dietary mead acid (MA, 5,8,11-eicosatrienoic acid) supplementation on N-methyl-N-nitrosourea (MNU)-induced cataract and retinal degeneration in Sprague-Dawley rats. Experiment 1 was designed to inhibit cataract formation, with the dams fed a 2.4% MA or basal (<0.01% MA) diet during lactational periods. On postnatal day 7, male pups received a single intraperitoneal (ip) injection of 50 mg/kg MNU or vehicle. Lens opacity and morphology were examined 7 and 14 days after the MNU injection. Experiment 2 was designed to inhibit retinal degeneration and was performed with female postweaning rats. In this experiment, dams were fed the 2.4% MA or basal diet during the lactational periods. Thereafter, the female pups were continuously fed the same diets during their postweaning periods. On postnatal day 21 (at weaning), pups received a single ip injection of 50 mg/kg MNU. Retinal morphology was examined 7 days after the MNU injection. In experiment 3, six-week-old female rats were fed the 2.4% MA or basal diet starting at one week before the MNU injection and were then continuously fed the same diets until sacrifice. Rats at 7 weeks of age were given a single ip injection of 40 mg/kg MNU, and the retina was then examined morphologically one week after the MNU injection. In experiment 1, mature cataract was found in all of the MNU-treated groups, with or without MA supplementation. In experiments 2 and 3, atrophy of both the peripheral and central outer retina occurred in all rats exposed to MNU, with or without MA supplementation, respectively. The severities of the cataracts and retinal atrophy in the rats were similar regardless of MA supplementation. Dietary mead acid, which is used as a substitute in essential fatty acid deficiency in the body, does not modify MNU-induced cataract and retinal degeneration in rat models.

  18. Hydrogen atoms in acetylsalicylic acid (Aspirin): the librating methyl group and probing the potential well in the hydrogen-bonded dimer

    NASA Astrophysics Data System (ADS)

    Wilson, Chick C.

    2001-02-01

    The structure of acetylsalicylic acid (2-(acetoyloxy)benzoic acid; Aspirin) has been studied by variable temperature single crystal neutron diffraction. The usual large torsional librational motion of the terminal methyl group is observed and its temperature dependence analysed using a simple model for the potential, yielding the force constant and barrier height for this motion. In addition, asymmetry of the scattering density of the proton involved in the hydrogen bond forming the carboxylic acid dimer motif is observed at temperatures above 200 K. This asymmetry is discussed in terms of its possible implications for the shape of the hydrogen bonding potential well.

  19. The methyl ester of okadaic acid is more potent than okadaic acid in disrupting the actin cytoskeleton and metabolism of primary cultured hepatocytes

    PubMed Central

    Espiña, Begoña; Louzao, MCarmen; Cagide, Eva; Alfonso, Amparo; Vieytes, Mercedes R; Yasumoto, Takeshi; Botana, Luis M

    2010-01-01

    Background and purpose: Okadaic acid (OA) and microcystins (MCs) are structurally different toxins with the same mechanism of action, inhibition of serine/threonine protein phosphatases (PPs). Methyl okadaate (MeOk), a methyl ester derivative of OA, was considered almost inactive due to its weak inhibition of PP1 and PP2A. Here, we have investigated the activity and potency of MeOk in hepatic cells in comparison with that of OA and MCs. Experimental approach: We tested the effects of MeOK, OA and microcystin-leucine and arginine (MC-LR) on the metabolic rate, the actin cytoskeleton and glucose uptake in a rat hepatocyte cell line (Clone 9) and in primary cultured rat hepatocytes. PP2A was assayed to compare OA and MeOk activity. Key results: MeOk disrupted the actin cytoskeleton and depressed the metabolic rate of both types of rat hepatocytes, being six-fold less potent than OA in Clone 9 cells but nearly six-fold more potent in primary cultured hepatocytes. However, unlike OA, MeOk did not change glucose uptake in these cells, suggesting a weak inhibition of PP2A, as confirmed in direct assays of PP2A activity. Conclusions and implications: Although MeOk was originally described as a weakly bioactive molecule, it clearly depressed the metabolic rate and disrupted the cytoskeleton in primary and immortalized rat hepatocytes. Furthermore, MeOk affected primary hepatocytes at much lower concentrations than those affecting immortalized cells. These effects were unrelated to PP2A inhibition. Our results suggest the risk to public health from MeOk in foodstuffs should be re-evaluated. PMID:20015092

  20. [Comparative assessment of Cladophora, Spirogyra and Oedogonium biomass for the production of fatty acid methyl esters].

    PubMed

    Haq, I; Muhammad, A; Hameed, U

    2014-01-01

    The use of alternative fuels for the mitigation of ecological impacts by use of diesel has been focus of intensive research. In the present work, algal oils extracted from cultivated biomass of Cladophora sp., Spirogyra sp. and Oedogonium sp. were evaluated for the lipase-mediated synthesis of fatty acid monoalkyl esters (FAME, biodiesel). To optimize the transesterification of these oils, different parameters such as the alkyl group donor, reaction temperature, stirring time and oil to alcohol ratio were investigated. Four different alcohols i.e. methanol, ethanol, n-propanol and n-butanol were tested as alkyl group donor for the biosynthesis FAME and methanol was found to be the best. Similarly, temperature 50 C and stirring time of 6 h were optimized for the transesterification of oils with methanol. The maximum biodiesel conversions from Cladophora (75.0%), Spirogyra (87.5%) and Oedogonium (92.0%) were obtained when oil to alcohol ratio was 1 : 8.

  1. Structure of cis-1-([4-(1-imidazolylmethyl)cyclohexyl]methyl)imidazole- succinic acid complex.

    PubMed

    Van Roey, P; Bullion, K A; Osawa, Y; Bowman, R M; Braun, D G

    1991-05-15

    CGS 14796C, C14H20N4.C4H6O4, Mr = 362.43, monoclinic, C2/c, a = 28.148 (4), b = 9.722 (1), c = 19.200 (2) A, beta = 133.06 (1) degree, V = 3838.88 A3, Z = 8, Dx = 1.26 Mg m-3, lambda (Cu K alpha) = 1.5418 A, mu 0.702 mm-1, F(000) = 1552, T = 294 K, R = 0.075 for all 3285 reflections. The structure is composed of linear chains of alternating CGS 14796C and succinic acid molecules. The CGS 14796C molecule is in an extended conformation.

  2. THz and mid-IR spectroscopy of interstellar ice analogs: methyl and carboxylic acid groups.

    PubMed

    Ioppolo, S; McGuire, B A; Allodi, M A; Blake, G A

    2014-01-01

    A fundamental problem in astrochemistry concerns the synthesis and survival of complex organic molecules (COMs) throughout the process of star and planet formation. While it is generally accepted that most complex molecules and prebiotic species form in the solid phase on icy grain particles, a complete understanding of the formation pathways is still largely lacking. To take full advantage of the enormous number of available THz observations (e.g., Herschel Space Observatory, SOFIA, and ALMA), laboratory analogs must be studied systematically. Here, we present the THz (0.3-7.5 THz; 10-250 cm(-1)) and mid-IR (400-4000 cm(-1)) spectra of astrophysically-relevant species that share the same functional groups, including formic acid (HCOOH) and acetic acid (CH3COOH), and acetaldehyde (CH3CHO) and acetone ((CH3)2CO), compared to more abundant interstellar molecules such as water (H2O), methanol (CH3OH), and carbon monoxide (CO). A suite of pure and mixed binary ices are discussed. The effects on the spectra due to the composition and the structure of the ice at different temperatures are shown. Our results demonstrate that THz spectra are sensitive to reversible and irreversible transformations within the ice caused by thermal processing, suggesting that THz spectra can be used to study the composition, structure, and thermal history of interstellar ices. Moreover, the THz spectrum of an individual species depends on the functional group(s) within that molecule. Thus, future THz studies of different functional groups will help in characterizing the chemistry and physics of the interstellar medium (ISM).

  3. Dietary supplementation with polyunsaturated fatty acid during pregnancy modulates DNA methylation at IGF2/H19 imprinted genes and growth of infants

    PubMed Central

    Lee, Ho-Sun; Barraza-Villarreal, Albino; Biessy, Carine; Duarte-Salles, Talita; Sly, Peter D.; Ramakrishnan, Usha; Rivera, Juan; Herceg, Zdenko

    2014-01-01

    Epigenetic regulation of imprinted genes is regarded as a highly plausible explanation for linking dietary exposures in early life with the onset of diseases during childhood and adulthood. We sought to test whether prenatal dietary supplementation with docosahexaenoic acid (DHA) during pregnancy may modulate epigenetic states at birth. This study was based on a randomized intervention trial conducted in Mexican pregnant women supplemented daily with 400 mg of DHA or a placebo from gestation week 18–22 to parturition. We applied quantitative profiling of DNA methylation states at IGF2 promoter 3 (IGF2 P3), IGF2 differentially methylated region (DMR), and H19 DMR in cord blood mononuclear cells of the DHA-supplemented group (n = 131) and the control group (n = 130). In stratified analyses, DNA methylation levels in IGF2 P3 were significantly higher in the DHA group than the control group in preterm infants (P = 0.04). We also observed a positive association between DNA methylation levels and maternal body mass index; IGF2 DMR methylation was higher in the DHA group than the control group in infants of overweight mothers (P = 0.03). In addition, at H19 DMR, methylation levels were significantly lower in the DHA group than the control group in infants of normal weight mothers (P = 0.01). Finally, methylation levels at IGF2/H19 imprinted regions were associated with maternal BMI. These findings suggest that epigenetic mechanisms may be modulated by DHA, with potential impacts on child growth and development. PMID:25293351

  4. 2-Acrylamido-2-methyl-1-propanesulfonic Acid Grafted Poly(vinylidene fluoride-co-hexafluoropropylene)-Based Acid-/Oxidative-Resistant Cation Exchange for Membrane Electrolysis.

    PubMed

    Pandey, Ravi P; Das, Arindam K; Shahi, Vinod K

    2015-12-30

    For developing acid-/oxidative-resistant aliphatic-polymer-based cation-exchange membrane (CEM), macromolecular modification of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) was carried out by controlled chemical grafting of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). To introduce the unsaturation suitable for chemical grafting, dehydrofluorination of commercially available PVDF-co-HFP was achieved under alkaline medium. Sulfonated copolymer (SCP) was prepared by the free radical copolymerization of dehydofluorinated PVDF-co-HFP (DHPVDF-co-HFP) and AMPS in the presence of free radical initiator. Prepared SCP-based CEMs were analyzed for their morphological characteristics, ion-exchange capacity (IEC), water uptake, conductivity, and stabilities (mechanical, chemical, and thermal) in comparison with state-of-art Nafion117 membrane. High bound water content avoids the membrane dehydration, and most optimal (SCP-1.33) membrane exhibited about ∼2.5-fold high bound water content in comparison with that of Nafion117 membrane. Bunsen reaction of iodine-sulfur (I-S) was successfully performed by direct-contact-mode membrane electrolysis in a two-compartment electrolytic cell using different SCP membranes. High current efficiency (83-99%) confirmed absence of any side reaction and 328.05 kJ mol-H2(-1) energy was required for to produce 1 mol of H2 by electrolytic cell with SCP-1.33 membrane. In spite of low conductivity for reported SCP membrane in comparison with that of Nafion117 membrane, SCP-1.33 membrane was assessed as suitable candidate for electrolysis because of its low-cost nature and excellent stabilities in highly acidic environment may be due to partial fluorinated segments in the membrane structure.

  5. An enhanced drought-tolerant method using SA-loaded PAMPS polymer materials applied on tobacco pelleted seeds.

    PubMed

    Guan, Yajing; Cui, Huawei; Ma, Wenguang; Zheng, Yunye; Tian, Yixin; Hu, Jin

    2014-01-01

    Drought is one of the most important stress factors limiting the seed industry and crop production. Present study was undertaken to create novel drought-resistant pelleted seeds using the combined materials with superabsorbent polymer, poly(2-acrylamide-2-methyl propane sulfonic acid) (PAMPS) hydrogel, and drought resistance agent, salicylic acid (SA). The optimized PAMPS hydrogel was obtained as the molar ratio of 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) to potassium peroxydisulfate (KPS) and N, N'-methylene-bis-acrylamide (MBA) was 1 : 0.00046 : 0.00134. The hydrogel weight after swelling in deionized water for 24 h reached 4306 times its own dry weight. The water retention ratio (RR) of PAMPS was significantly higher as compared with the control. It could keep as high as 85.3% of original weight after 30 min at 110 °C; even at 25 °C for 40 d, the PAMPS still kept RR at 33.67%. PAMPS disintegration ratio increased gradually and reached around 30% after embedding in soil or activated sludge for 60 d. In addition, there were better seed germination performance and seedling growth in the pelleted treatments with SA-loaded PAMPS hydrogel under drought stress than control. It suggested that SA-loaded PAMPS hydrogel, a nontoxic superabsorbent polymer, could be used as an effective drought resistance material applied to tobacco pelleted seeds.

  6. An Enhanced Drought-Tolerant Method Using SA-Loaded PAMPS Polymer Materials Applied on Tobacco Pelleted Seeds

    PubMed Central

    Guan, Yajing; Cui, Huawei; Ma, Wenguang; Zheng, Yunye; Tian, Yixin; Hu, Jin

    2014-01-01

    Drought is one of the most important stress factors limiting the seed industry and crop production. Present study was undertaken to create novel drought-resistant pelleted seeds using the combined materials with superabsorbent polymer, poly(2-acrylamide-2-methyl propane sulfonic acid) (PAMPS) hydrogel, and drought resistance agent, salicylic acid (SA). The optimized PAMPS hydrogel was obtained as the molar ratio of 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) to potassium peroxydisulfate (KPS) and N, N′-methylene-bis-acrylamide (MBA) was 1 : 0.00046 : 0.00134. The hydrogel weight after swelling in deionized water for 24 h reached 4306 times its own dry weight. The water retention ratio (RR) of PAMPS was significantly higher as compared with the control. It could keep as high as 85.3% of original weight after 30 min at 110°C; even at 25°C for 40 d, the PAMPS still kept RR at 33.67%. PAMPS disintegration ratio increased gradually and reached around 30% after embedding in soil or activated sludge for 60 d. In addition, there were better seed germination performance and seedling growth in the pelleted treatments with SA-loaded PAMPS hydrogel under drought stress than control. It suggested that SA-loaded PAMPS hydrogel, a nontoxic superabsorbent polymer, could be used as an effective drought resistance material applied to tobacco pelleted seeds. PMID:25250387

  7. Radiolabeled amino acids for tumor imaging with PET: radiosynthesis and biological evaluation of 2-amino-3-[18F]fluoro-2-methylpropanoic acid and 3-[18F]fluoro-2-methyl-2-(methylamino)propanoic acid.

    PubMed

    McConathy, Jonathan; Martarello, Laurent; Malveaux, Eugene J; Camp, Vernon M; Simpson, Nicholas E; Simpson, Chiab P; Bowers, Geoffrey D; Olson, Jeffrey J; Goodman, Mark M

    2002-05-23

    Novel radiopharmaceuticals, including amino acids, that target neoplasms through their altered metabolic states have shown promising results in preclinical and clinical studies. Two fluorinated analogues of alpha-aminoisobutyric acid, 2-amino-3-fluoro-2-methylpropanoic acid (FAMP) and 3-fluoro-2-methyl-2-(methylamino)propanoic acid (N-MeFAMP), have been radiolabeled with fluorine-18, characterized in amino acid uptake assays, and evaluated in vivo in normal rats and a rodent tumor model. The key steps in the syntheses of both radiotracers involved the preparation of cyclic sulfamidate precursors. Radiosyntheses of both [18F]FAMP and [18F]N-MeFAMP via no-carrier-added nucleophilic substitution provided high yields (>78% decay-corrected) in high radiochemical purity (>99%). Amino acid transport assays using 9L gliosarcoma cells demonstrated that both compounds are substrates for the A type amino acid transport system, with [18F]N-MeFAMP showing higher specificity than [18F]FAMP for A type transport. Tissue distribution studies in normal Fischer rats and Fischer rats implanted intracranially with 9L gliosarcoma tumor cells were also performed. At 60 min postinjection, the tumor vs normal brain ratio of radioactivity was 36:1 in animals receiving [18F]FAMP and 104:1 in animals receiving [18F]N-MeFAMP. On the basis of these studies, both [18F]FAMP and [18F]N-MeFAMP are promising imaging agents for the detection of intracranial neoplasms via positron emission tomography.

  8. A High Molar Extinction Coefficient Bisterpyridyl Homoleptic Ru(II) Complex with trans-2-Methyl-2-butenoic Acid Functionality: Potential Dye for Dye-Sensitized Solar Cells

    PubMed Central

    Adeloye, Adewale O.; Olomola, Temitope O.; Adebayo, Akinbulu I.; Ajibade, Peter A.

    2012-01-01

    In our continued efforts in the synthesis of ruthenium(II) polypyridine complexes as potential dyes for use in varied applications, such as the dye-sensitized solar cells (DSSCs), this work particularly describes the synthesis, absorption spectrum, redox behavior and luminescence properties of a new homoleptic ruthenium(II) complex bearing a simple trans-2-methyl-2-butenoic acid functionality as the anchoring ligand on terpyridine moiety. The functionalized terpyridine ligand: 4′-(trans-2-methyl-2-butenoic acid)-terpyridyl (L1) was synthesized by aryl bromide substitution on terpyridine in a basic reaction condition under palladium carbide catalysis. In particular, the photophysical and redox properties of the complex formulated as: bis-4′-(trans-2-methyl-2-butenoic acid)-terpyridyl ruthenium(II) bis-hexafluorophosphate [Ru(L1)2(PF6)2] are significantly better compared to those of [Ru(tpy)2]2+ and compare well with those of the best emitters of Ru(II) polypyridine family containing tridentate ligands. Reasons for the improved photophysical and redox properties of the complex may be attributed partly to the presence of a substituted α,β-unsaturated carboxylic acid moiety leading to increase in the length of π-conjugation bond thereby enhancing the MLCT-MC (Metal-to-ligand-charge transfer-metal centred) energy gap, and to the reduced difference between the minima of the excited and ground states potential energy surfaces. PMID:22489165

  9. Efficient production of fatty acid methyl ester from waste activated bleaching earth using diesel oil as organic solvent.

    PubMed

    Kojima, Seiji; Du, Dongning; Sato, Masayasu; Park, Enoch Y

    2004-01-01

    Fatty acid methyl ester (FAME) production from waste activated bleaching earth (ABE) discarded by the crude oil refining industry was investigated using fossil fuel as a solvent in the esterification of triglycerides. Lipase from Candida cylindracea showed the highest stability in diesel oil. Using diesel oil as a solvent, 3 h was sufficient to obtain a yield of approximately 100% of FAME in the presence of 10% lipase from waste ABE. Kerosene was also a good solvent in the esterification of triglycerides embedded in the waste ABE. Fuel analysis showed that the FAME produced using diesel oil as a solvent complied with the Japanese diesel standard and the 10% residual carbon amount was lower than that of FAME produced using other solvents. Use of diesel oil as solvent in the FAME production from the waste ABE simplified the process, because there was no need to separate the organic solvent from the FAME-solvent mixture. These results demonstrate a promising reutilization method for the production of FAME, for use as a biodiesel, from industrial waste resources containing waste vegetable oils.

  10. Non-classical mechanism of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor channel block by fluoxetine.

    PubMed

    Barygin, Oleg I; Komarova, Margarita S; Tikhonova, Tatiana B; Tikhonov, Denis B

    2015-04-01

    Antidepressants have many targets in the central nervous system. A growing body of data demonstrates the influence of antidepressants on glutamatergic neurotransmission. In the present work, we studied the inhibition of native Ca(2+)-permeable and Ca(2+)-impermeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in rat brain neurons by fluoxetine. The Ca(2+)-impermeable AMPA receptors in CA1 hippocampal pyramidal neurons were weakly affected. The IC50 value for the inhibition of Ca(2+)-permeable AMPA receptors in giant striatal interneurons was 43 ± 7 μM. The inhibition of Ca(2+)-permeable AMPA receptors was voltage dependent, suggesting deep binding in the pore. However, the use dependence of fluoxetine action differed markedly from that of classical AMPA receptor open-channel blockers. Moreover, fluoxetine did not compete with other channel blockers. In contrast to fluoxetine, its membrane-impermeant quaternary analog demonstrated all of the features of channel inhibition typical for open-channel blockers. It is suggested that fluoxetine reaches the binding site through a hydrophobic access pathway. Such a mechanism of block is described for ligands of sodium and calcium channels, but was never found in AMPA receptors. Molecular modeling suggests binding of fluoxetine in the subunit interface; analogous binding was proposed for local anesthetics in closed sodium channels and for benzothiazepines in calcium channels.

  11. Formation of protoporphyrin IX in mouse skin after topical application of 5-aminolevulinic acid and its methyl esther

    NASA Astrophysics Data System (ADS)

    Sorensen, Roar; Juzenas, Petras; Iani, Vladimir; Moan, Johan

    1999-02-01

    Normal skin of nude mice (Balb/c) was treated topically with 5-aminolevulinic acid (ALA) and its methyl ester (ALA-Me) for 24 hours. Approximately 0.1 gram of freshly prepared cream was applied to a spot of 1 cm2 on the flank of the mice, which was then covered with a transparent dressing. The ALA induced protoporphyrin IX (PpIX) was studied by means of a noninvasive fiber-optic fluorescence probe connected to a luminescence spectrometer. The excitation wavelength was 407 nm, and the emission wavelength was 637 nm. For the first hour a slight lag in PpIX production was observed for the mice treated with ALA-Me compared to the mice treated with ALA. After approximately 12 hours the ALA and the ALA-Me treated mice showed the same PpIX fluorescence intensity. From 12 hours until 24 hours the PpIX fluorescence intensity decreased for both treatment modalities, even though ALA and ALA-Me were continuously present. At 24 hours ALA-Me-treated mice had less than half the amount of PpIX in their skin compared with ALA- treated mice.

  12. Structural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) copolymer by nuclear magnetic resonance and mass spectrometry.

    PubMed

    Giordanengo, Rémi; Viel, Stéphane; Hidalgo, Manuel; Allard-Breton, Béatrice; Thévand, André; Charles, Laurence

    2009-11-03

    Mass spectrometry (MS) and nuclear magnetic resonance (NMR) have been combined to achieve the complete microstructural characterization of a poly(methacrylic acid)-poly(methyl methacrylate) (PMAA-PMMA) copolymer synthesized by nitroxide-mediated polymerization. Various PMAA-PMMA species could be identified which mainly differ in terms of terminaisons. 1H and 13C NMR experiments revealed the structure of the end-groups as well as the proportion of each co-monomer in the copolymers. These end-group masses were further confirmed from m/z values of doubly charged copolymer anions detected in the single stage mass spectrum. In contrast, copolymer composition derived from MS data was not consistent with NMR results, obviously due to strong mass bias well known to occur during electrospray ionization of these polymeric species. Tandem mass spectrometry could reveal the random nature of the copolymer based on typical dissociation reactions, i.e., water elimination occurred from any two contiguous MAA units while MAA-MMA pairs gave rise to the loss of a methanol molecule. Polymer backbone cleavages were also observed to occur and gave low abundance fragment ions which allowed the structure of the initiating end-group to be confirmed.

  13. Prolonged Hypocalcemic Effect by Pulmonary Delivery of Calcitonin Loaded Poly(Methyl Vinyl Ether Maleic Acid) Bioadhesive Nanoparticles

    PubMed Central

    Varshosaz, J.; Minaiyan, M.; Forghanian, M.

    2014-01-01

    The purpose of the present study was to design a pulmonary controlled release system of salmon calcitonin (sCT). Therefore, poly(methyl vinyl ether maleic acid) [P(MVEMA)] nanoparticles were prepared by ionic cross-linking method using Fe2+ and Zn2+ ions. Physicochemical properties of nanoparticles were studied in vitro. The stability of sCT in the optimized nanoparticles was studied by electrophoretic gel method. Plasma calcium levels until 48 h were determined in rats as pulmonary-free sCT solution or nanoparticles (25 μg·kg−1), iv solution of sCT (5 μg·kg−1), and pulmonary blank nanoparticles. The drug remained stable during fabrication and tests on nanoparticles. The optimized nanoparticles showed proper physicochemical properties. Normalized reduction of plasma calcium levels was at least 2.76 times higher in pulmonary sCT nanoparticles compared to free solution. The duration of hypocalcemic effect of pulmonary sCT nanoparticles was 24 h, while it was just 1 h for the iv solution. There was not any significant difference between normalized blood calcium levels reduction in pulmonary drug solution and iv injection. Pharmacological activity of nanoparticles after pulmonary delivery was 65% of the iv route. Pulmonary delivery of P(MVEMA) nanoparticles of sCT enhanced and prolonged the hypocalcemic effect of the drug significantly. PMID:24701588

  14. Superparamagnetic poly(methyl methacrylate) nanoparticles surface modified with folic acid presenting cell uptake mediated by endocytosis

    NASA Astrophysics Data System (ADS)

    Feuser, Paulo Emilio; Jacques, Amanda Virtuoso; Arévalo, Juan Marcelo Carpio; Rocha, Maria Eliane Merlin; dos Santos-Silva, Maria Claudia; Sayer, Claudia; de Araújo, Pedro H. Hermes

    2016-04-01

    The encapsulation of superparamagnetic nanoparticles (MNPs) in polymeric nanoparticles (NPs) with modified surfaces can improve targeted delivery and induce cell death by hyperthermia. The goals of this study were to synthesize and characterize surface modified superparamagnetic poly(methyl methacrylate) with folic acid (FA) prepared by miniemulsion polymerization (MNPsPMMA-FA) and to evaluate their in vitro cytotoxicity and cellular uptake in non-tumor cells, murine fibroblast (L929) cells and tumor cells that overexpressed folate receptor (FR) β, and chronic myeloid leukemia cells in blast crisis (K562). Lastly, hemolysis assays were performed on human red blood cells. MNPsPMMA-FA presented an average mean diameter of 135 nm and a saturation magnetization (Ms) value of 37 emu/g of iron oxide, as well as superparamagnetic behavior. The MNPsPMMA-FA did not present cytotoxicity in L929 and K562 cells. Cellular uptake assays showed a higher uptake of MNPsPMMA-FA than MNPsPMMA in K562 cells when incubated at 37 °C. On the other hand, MNPsPMMA-FA showed a low uptake when endocytosis mechanisms were blocked at low temperature (4 °C), suggesting that the MNPsPMMA-FA uptake was mediated by endocytosis. High concentrations of MNPsPMMA-FA showed hemocompatibility when incubated for 24 h in human red blood cells. Therefore, our results suggest that these carrier systems can be an excellent alternative in targeted drug delivery via FR.

  15. FT-IR, Laser-Raman spectra and computational analysis of 5-Methyl-3-phenylisoxazole-4-carboxylic acid.

    PubMed

    Sert, Yusuf; Mahendra, M; Keskinoğlu, S; Chandra; Srikantamurthy, N; Umesha, K B; Çırak, Ç

    2015-03-15

    In this study the experimental and theoretical vibrational frequencies of a newly synthesized anti-tumor, antiviral, hypoglycemic, antifungal and anti-HIV agent namely, 5-Methyl-3-phenylisoxazole-4-carboxylic acid has been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths, bond angles and torsion angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr and DFT/M06-2X: highly parametrized, empirical exchange correlation function) with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated by using the same theoretical calculations.

  16. FT-IR, Laser-Raman spectra and computational analysis of 5-Methyl-3-phenylisoxazole-4-carboxylic acid

    NASA Astrophysics Data System (ADS)

    Sert, Yusuf; Mahendra, M.; Keskinoğlu, S.; Chandra; Srikantamurthy, N.; Umesha, K. B.; Çırak, Ç.

    2015-03-01

    In this study the experimental and theoretical vibrational frequencies of a newly synthesized anti-tumor, antiviral, hypoglycemic, antifungal and anti-HIV agent namely, 5-Methyl-3-phenylisoxazole-4-carboxylic acid has been investigated. The experimental FT-IR (4000-400 cm-1) and Laser-Raman spectra (4000-100 cm-1) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths, bond angles and torsion angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr and DFT/M06-2X: highly parametrized, empirical exchange correlation function) with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated by using the same theoretical calculations.

  17. Chlorpyrifos-methyl solubilisation by humic acids used as bio-surfactants extracted from lignocelluloses and kitchen wastes.

    PubMed

    Scaglia, Barbara; Baglieri, Andrea; Tambone, Fulvia; Gennari, Mara; Adani, Fabrizio

    2016-09-01

    Chlorpyrifos-methyl (CLP-m) is a widely used organophosphate insecticide that can accumulate in soil and become toxic to humans. CLP-m can be removed from soil by its solubilisation using synthetic surfactants. However, synthetic surfactants can accumulate in soil causing contamination phenomena themselves. Bio-surfactants can be used as an alternative to synthetic ones, reducing costs and environmental issues. In this work, humic acid (HA) extracted from raw biomasses, i.e. lignocelluloses (HAL) and lignocelluloses plus kitchen food waste (HALF), corresponding composts (C) (HALC and HALFC) and leonardite (HAc), were tested in comparison with commercial surfactants, i.e. SDS, Tween 20 and DHAB, to solubilize CLP-m. Results obtained indicated that only biomass-derived HA, composted biomass-derived HA, and SDS solubilized CLP-m: SDS = 0.006; HAL = 0.007; HALC = 0.009 g; HALF = 0.025; HALFC = 0.024) (g CLP-m g(-1) surfactant). Lignocelluloses HAs (HAL, HALF) solubilized CLP-m just as well as SDS while lignocellulosic plus kitchen food waste HA (HALF, HALFC) showed a three times higher CLP-m solubilisation capability. This difference was attributed to the higher concentration of alkyl-Carbon that creates strong links with CLP-m in the hydrophobic micelle-core of the surfactants.

  18. Effect of methacrylic acid:methyl methacrylate monomer ratios on polymerization rates and properties of polymethyl methacrylates.

    PubMed

    Chen, T; Kusy, R P

    1997-08-01

    Five binary formulations were prepared from methyl methacrylate (MMA) and methacrylic acid (MAA) monomers, and six ternary formulations were prepared from polysols of 30% wt polymethyl methacrylate (PMMA)/MMA and MAA. Using thermal analyses (DSC and TGA) the polymerization kinetics, condition of postcuring, relative amount of residual monomers, and glass transition temperature (Tg) were determined. From bar-shaped samples, 25 x 5 x 0.9 mm in dimensions, mechanical properties [flexural moduli (E) and maximum strengths (sigma)] were measured in three-point bending. Polymerization kinetics of binary formulations improved over pure PMMA (from 15 to 4 min) as a result of over a 60-fold increase in propagation-to-termination constants (Kp/Kt) of MAA/MMA. The further addition of PMMA increased the viscosity, slowed down termination, and, consequently, improved the polymerization kinetics twofold. These enhancements occurred without a substantive change in the Tg of the ternary system (ca. 107 degrees C) over pure PMMA (ca. 112 degrees C). Moreover, the Es of the four ternary formulations averaged 2.94 GPa, which was comparable with many values reported in the literature. In contrast the sigma s of these same formulations averaged 97 MPa, which was about 25% better than earlier investigations of pure acrylic. When a thermoplastic material is required for pultruding profiles that cure fast and have good thermal-mechanical properties, ternaries of PMMA/MMA/MAA should be considered.

  19. Recovery from severe frontotemporal dysfunction at 3years after N-methyl-d-aspartic acid (NMDA) receptor antibody encephalitis.

    PubMed

    Leypoldt, Frank; Gelderblom, Mathias; Schöttle, Daniel; Hoffmann, Sascha; Wandinger, Klaus-Peter

    2013-04-01

    Encephalitis associated with antibodies against N-methyl-d-aspartic acid (NMDA) receptor is characterized by severe memory deficits, decreased consciousness, epileptic seizures and movement disorders and occurs most commonly in young women. Recovery is mostly good but little is known about the disease course in patients whose treatment has been delayed severely. We present a 16-year-old girl with a 36-month follow-up. A single course of methylprednisolone attenuated some symptoms but severe and incapacitating frontotemporal syndrome remained. Second-line treatment with rituximab was initiated 12months after the onset of symptoms. A surprising recovery occurred 18months after treatment and 30months after onset. Recovery in NMDA receptor antibody-associated encephalitis can be severely delayed and does not have to be linear. Whether delayed therapy contributed to recovery in this patient cannot be answered with certainty. Spontaneous recovery independent of therapy is possible, as it has been observed previously as late as 3years after onset. Although serum antibodies disappeared with recovery in this patient, previous cases have shown serum antibodies to be unreliable markers of disease activity. Second-line treatment, especially with substances as well tolerated as rituximab, should at least be considered in NMDA receptor encephalitis with persistent neuropsychiatric syndromes after first-line therapy.

  20. O-(triazolyl)methyl carbamates as a novel and potent class of fatty acid amide hydrolase (FAAH) inhibitors.

    PubMed

    Colombano, Giampiero; Albani, Clara; Ottonello, Giuliana; Ribeiro, Alison; Scarpelli, Rita; Tarozzo, Glauco; Daglian, Jennifer; Jung, Kwang-Mook; Piomelli, Daniele; Bandiera, Tiziano

    2015-02-01

    Inhibition of fatty acid amide hydrolase (FAAH) activity is under investigation as a valuable strategy for the treatment of several disorders, including pain and drug addiction. A number of potent FAAH inhibitors belonging to different chemical classes have been disclosed to date; O-aryl carbamates are one of the most representative families. In the search for novel FAAH inhibitors, a series of O-(1,2,3-triazol-4-yl)methyl carbamate derivatives were designed and synthesized exploiting a copper- catalyzed [3+2] cycloaddition reaction between azides and alkynes (click chemistry). Exploration of the structure-activity relationships within this new class of compounds identified potent inhibitors of both rat and human FAAH with IC50 values in the single-digit nanomolar range. In addition, these derivatives showed improved stability in rat plasma and kinetic solubility in buffer with respect to the lead compound. Based on the results of the study, the novel analogues identified can be considered to be promising starting point for the development of new FAAH inhibitors with improved drug-like properties.

  1. Host-guest inclusion system of oleanolic acid with methyl-β-cyclodextrin: Preparation, characterization and anticancer activity

    NASA Astrophysics Data System (ADS)

    Ren, Yufeng; Liu, Ying; Niu, Raomei; Liao, Xiali; Zhang, Jihong; Yang, Bo

    2016-08-01

    In this study, the solid inclusion complex of oleanolic acid (OA) with methyl-β-cyclodextrin (M-β-CD) was prepared and characterized by nuclear magnetic resonance (NMR), X-ray diffraction (XRD), scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The inclusion behaviors of OA/M-β-CD complex were studied by fluorescence spectroscopy and the Job plot, which indicated a 1:1 inclusion mode between OA and M-β-CD. The stability constant (Ks) of the complex was 1072.30 ± 20 M-1 determined by spectral titration at 25 °C. Besides, the water solubility of OA was significantly increased to 8.2 mg/mL by inclusion complexation, compared to only ca. 0.012 μg/mL of free OA. The in vitro cytotoxicity of the inclusion complex was noticeably better than that of native OA with the IC50 values of 8.89, 7.89 and 5.77 μM on human cancer cell lines HepG2, HT29 and HCT116, respectively, by MTT assay.

  2. Protective effects of PF-4708671 against N-methyl-d-aspartic acid-induced retinal damage in rats.

    PubMed

    Hayashi, Ikumi; Aoki, Yuto; Ushikubo, Hiroko; Asano, Daiki; Mori, Asami; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2016-12-01

    We previously demonstrated that rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR), protects against N-methyl-d-aspartic acid (NMDA)-induced retinal damage in rats. Rapamycin inhibits mTOR activity, thereby preventing the phosphorylation of ribosomal protein S6, which is a downstream target of S6 kinase. Therefore, we aimed to determine whether PF-4708671, an inhibitor of S6 kinase, protects against NMDA-induced retinal injury. Intravitreal injection of NMDA (200 nmol/eye) caused cell loss in the ganglion cell layer and neuroinflammatory responses, such as an increase in the number of CD45-positive leukocytes and Iba1-positive microglia. Surprisingly, simultaneous injection of PF-4708671 (50 nmol/eye) with NMDA significantly attenuated these responses without affecting phosphorylated S6 levels. These results suggest that PF-4708671 and rapamycin likely protect against NMDA-induced retinal damage via distinct pathways. The neuroprotective effect of PF-4708671 is unlikely to be associated with inhibition of the S6 kinase, even though PF-4708671 is reported to be a S6 kinase inhibitor.

  3. Electronic transition moments of 6-methyl isoxanthopterin--a fluorescent analogue of the nucleic acid base guanine.

    PubMed

    Widom, Julia R; Rappoport, Dmitrij; Perdomo-Ortiz, Alejandro; Thomsen, Hanna; Johnson, Neil P; von Hippel, Peter H; Aspuru-Guzik, Alán; Marcus, Andrew H

    2013-01-01

    Fluorescent nucleic acid base analogues are important spectroscopic tools for understanding local structure and dynamics of DNA and RNA. We studied the orientations and magnitudes of the electric dipole transition moments (EDTMs) of 6-methyl isoxanthopterin (6-MI), a fluorescent analogue of guanine that has been particularly useful in biological studies. Using a combination of absorption spectroscopy, linear dichroism (LD) and quantum chemical calculations, we identified six electronic transitions that occur within the 25,000-50,000 cm(-1) spectral range. Our results indicate that the two experimentally observed lowest-energy transitions, which occur at 29,687 cm(-1) (337 nm) and 34,596 cm(-1) (289 nm), are each polarized within the plane of the 6-MI base. A third in-plane polarized transition is experimentally observed at 47,547 cm(-1) (210 nm). The theoretically predicted orientation of the lowest-energy transition moment agrees well with experiment. Based on these results, we constructed an exciton model to describe the absorption spectra of a 6-MI dinucleotide-substituted double-stranded DNA construct. This model is in good agreement with the experimental data. The orientations and intensities of the low-energy electronic transitions of 6-MI reported here should be useful for studying local conformations of DNA and RNA in biologically important complexes.

  4. Use of fatty acid methyl ester profiles for discrimination of Bacillus cereus T-strain spores grown on different media.

    PubMed

    Ehrhardt, Christopher J; Chu, Vivian; Brown, TeeCie; Simmons, Terrie L; Swan, Brandon K; Bannan, Jason; Robertson, James M

    2010-03-01

    The goal of this study was to determine if cellular fatty acid methyl ester (FAME) profiling could be used to distinguish among spore samples from a single species (Bacillus cereus T strain) that were prepared on 10 different medium formulations. To analyze profile differences and identify FAME biomarkers diagnostic for the chemical constituents in each sporulation medium, a variety of statistical techniques were used, including nonmetric multidimensional scaling (nMDS), analysis of similarities (ANOSIM), and discriminant function analysis (DFA). The results showed that one FAME biomarker, oleic acid (18:1 omega9c), was exclusively associated with spores grown on Columbia agar supplemented with sheep blood and was indicative of blood supplements that were present in the sporulation medium. For spores grown in other formulations, multivariate comparisons across several FAME biomarkers were required to discern profile differences. Clustering patterns in nMDS plots and R values from ANOSIM revealed that dissimilarities among FAME profiles were most pronounced when spores grown with disparate sources of complex additives or protein supplements were compared (R > 0.8), although other factors also contributed to FAME differences. DFA indicated that differentiation could be maximized with a targeted subset of FAME variables, and the relative contributions of branched FAME biomarkers to group dissimilarities changed when different media were compared. When taken together, these analyses indicate that B. cereus spore samples grown in different media can be resolved with FAME profiling and that this may be a useful technique for providing intelligence about the production methods of Bacillus organisms in a forensic investigation.

  5. Fatty Acid Methyl Ester (FAME) Succession in Different Substrates as Affected by the Co-Application of Three Pesticides

    PubMed Central

    Cardinali, Alessandra; Pizzeghello, Diego; Zanin, Giuseppe

    2015-01-01

    Introduction In intensive agriculture areas the use of pesticides can alter soil properties and microbial community structure with the risk of reducing soil quality. Materials and Methods In this study the fatty acid methyl esters (FAMEs) evolution has been studied in a factorial lab experiment combining five substrates (a soil, two aged composts and their mixtures) treated with a co-application of three pesticides (azoxystrobin, chlorotoluron and epoxiconazole), with two extraction methods, and two incubation times (0 and 58 days). FAMEs extraction followed the microbial identification system (MIDI) and ester-linked method (EL). Results and Discussion The pesticides showed high persistence, as revealed by half-life (t1/2) values ranging from 168 to 298 days, which confirms their recalcitrance to degradation. However, t1/2 values were affected by substrate and compost age down to 8 days for chlorotoluron in S and up to 453 days for epoxiconazole in 12M. Fifty-six FAMEs were detected. Analysis of variance (ANOVA) showed that the EL method detected a higher number of FAMEs and unique FAMEs than the MIDI one, whereas principal component analysis (PCA) highlighted that the monosaturated 18:1ω9c and cyclopropane 19:0ω10c/19ω6 were the most significant FAMEs grouping by extraction method. The cyclopropyl to monoenoic acids ratio evidenced higher stress conditions when pesticides were applied to compost and compost+soil than solely soil, as well as with final time. Conclusion Overall, FAMEs profiles showed the importance of the extraction method for both substrate and incubation time, the t1/2 values highlighted the effectiveness of solely soil and the less mature compost in reducing the persistence of pesticides. PMID:26694029

  6. Use of Fatty Acid Methyl Ester Profiles for Discrimination of Bacillus cereus T-Strain Spores Grown on Different Media▿

    PubMed Central

    Ehrhardt, Christopher J.; Chu, Vivian; Brown, TeeCie; Simmons, Terrie L.; Swan, Brandon K.; Bannan, Jason; Robertson, James M.

    2010-01-01

    The goal of this study was to determine if cellular fatty acid methyl ester (FAME) profiling could be used to distinguish among spore samples from a single species (Bacillus cereus T strain) that were prepared on 10 different medium formulations. To analyze profile differences and identify FAME biomarkers diagnostic for the chemical constituents in each sporulation medium, a variety of statistical techniques were used, including nonmetric multidimensional scaling (nMDS), analysis of similarities (ANOSIM), and discriminant function analysis (DFA). The results showed that one FAME biomarker, oleic acid (18:1 ω9c), was exclusively associated with spores grown on Columbia agar supplemented with sheep blood and was indicative of blood supplements that were present in the sporulation medium. For spores grown in other formulations, multivariate comparisons across several FAME biomarkers were required to discern profile differences. Clustering patterns in nMDS plots and R values from ANOSIM revealed that dissimilarities among FAME profiles were most pronounced when spores grown with disparate sources of complex additives or protein supplements were compared (R > 0.8), although other factors also contributed to FAME differences. DFA indicated that differentiation could be maximized with a targeted subset of FAME variables, and the relative contributions of branched FAME biomarkers to group dissimilarities changed when different media were compared. When taken together, these analyses indicate that B. cereus spore samples grown in different media can be resolved with FAME profiling and that this may be a useful technique for providing intelligence about the production methods of Bacillus organisms in a forensic investigation. PMID:20097814

  7. Spatial variation in 2-methyl-4-chlorophenoxyacetic acid mineralization and sorption in a sandy soil at field level.

    PubMed

    Fredslund, L; Vinther, F P; Brinch, U C; Elsgaard, L; Rosenberg, P; Jacobsen, C S

    2008-01-01

    The phenoxyacetic acid herbicide MCPA (2-methyl-4-chlorophenoxyacetic acid) is frequently detected in groundwater beneath Danish agricultural fields. We investigated spatial variation in microbial MCPA mineralization potential in a flat agricultural field of fine sandy soil (USDA classification: Humic Dystrudept) located on the Yoldia plains of Northern Jutland, Denmark. Samples for determination of MCPA mineralization and sorption were collected from the Ap and Bs horizons at 51 sampling sites located in a 200 x 220 m grid. Spatial variation in sorption was low in both horizons (distribution coefficient, 0.36-4.16 L kg(-1)). Sorption correlated strongly with soil organic carbon content in both horizons (CV, 93 and 83%, respectively) and negatively with soil pH. [Ring-(14)C]-MCPA mineralized readily in the Ap horizon, with 49 to 62% of the (14)C-MCPA being converted to (14)CO(2) during the 67-d incubation period. With the subsoil, mineralization of (14)C-MCPA varied considerably between samples (0.5-72.8%). At neither depth was there correlation between (14)C-MCPA mineralization and sorption, soil pH, organic carbon content, clay content, number of colony-forming units (CFU), pseudomonad CFU, or any of the four microbial activity parameters measured. The presence of microbial genes encoding for the TfdA enzyme was quantified using real-time polymerase chain reaction. No correlation was found between MCPA mineralization potential and the natural background number of tfdA genes present in the soil samples. The degradation kinetics suggests that the high (14)C-MCPA mineralization rate detected in soil samples was linked to growth of the MCPA-degrading soil microbial community.

  8. Nβ-methylation changes the recognition pattern of aza-β3-amino acid containing peptidomimetic substrates by protein kinase A

    PubMed Central

    2011-01-01

    The protein kinase A (PKA)-catalyzed phosphorylation of peptide substrate RRASVA analogs, containing Nβ-Me-aza-β3-amino acid residues in all subsequent positions, was studied. This work follows along the lines of our previous research of the phosphorylation of aza-β3-analogs of RRASVA (the shortest active substrate of PKA) and allows characterizing the influence of Nβ-methylation of aza-β3-amino acid residues on substrate recognition by PKA on substrate binding and phosphorylation steps. It was found that the effect of Nβ-methylation was dependent upon the position of the structure alteration. Moreover, the presence of a single Nβ-methylation site in the substrate changed the recognition pattern of this series of peptidomimetics, strongly affecting the phosphorylation step. Structure modeling of aza-β3- and Nβ-Me-aza-β3-containing substrates revealed that Nβ-methylation of aza-β3-moieties changed the peptide bond geometry from trans- to cis-configuration in -CO-NMe- fragments, with an exception for the N-terminally methylated Nβ-Me-aza-β3-RRRASVA (with the N-terminal amino group not participating in the peptide bond) and RRAS-Nβ-Me-aza-β3-VA. As has been shown in literature, this conformational preference of the backbone has a significant influence on the flexibility of the peptide substrate chain. Following our results, this property seems to have significant influence on the recognition of the amino acid side groups by the enzyme binding site, and in the case of PKA this structural modification was decisive for the phosphate transfer step of the catalytic process. PMID:22373236

  9. Bis(tetra-methyl-amonium) bis-(2,4,5-carboxy-benzoate)-benzene-1,2,4,5-tetra-carboxylic acid (1/1).

    PubMed

    Cunha-Silva, Luís; Girginova, Penka I; Trindade, Tito; Rocha, João; Klinowski, Jacek; Almeida Paz, Filipe A

    2007-12-06

    The asymmetric unit of the title compound, 2C(4)H(12)N(+)·2C(10)H(5)O(8) (-)·C(10)H(6)O(8), consists of a tetra-methyl-amonium cation, an anion derived from the singly deprotonated pyromellitic acid anion, 2,4,5-carboxy-benzoate (H(3)bta(-)), and one-half of a benzene-1,2,4,5-tetra-carboxylic acid (H(4)bta) mol-ecule, which has the centroid of the aromatic ring positioned at a crystallographic centre of inversion. The H(4)bta and H(3)bta(-) residues are involved in an extensive inter-molecular O-H⋯O hydrogen-bonding network, which leads to a three-dimensional supra-molecular structure containing one-dimensional channels running parallel to the [001] crystallographic direction. These channels house the tetra-methyl-amonium cations.

  10. Analytical studies of the interaction of Tb(III)-2-{[(4-methoxy benzoyl) oxy]} methyl benzoic acid binary complex with nucleosides

    NASA Astrophysics Data System (ADS)

    Shehata, A. M. A.; Azab, H. A.; El-assy, N. B.; Anwar, Z. M.; Mostafa, H. M.

    2016-01-01

    The interaction of Tb(III)-2-{[(4-methoxy benzoyl) oxy]} methyl benzoic acid binary complex with nucleosides (adenosine, cytidine, guanosine and inosine) was investigated using UV and fluorescence methods. The reaction of Tb-complex with cytidine, guanosine and adenosine is accompanied by shift to longer wavelength in the absorption band, while there is a blue shift in the absorption band with an enhancement in the molar absorptivity upon the reaction with inosine. The fluorescence intensity of Tb(III)-2-{[(4- methoxy benzoyl) oxy]} methyl benzoic acid binary complex at λ = 545 nm (5D4 → 7F5) was decreased with the addition of the nucleoside molecule following the order: cytidine > inosine > guanosine > adenosine.

  11. Structure of the PLP Degradative Enzyme 2-Methyl-3-hydroxypyridine-5-carboxylic Acid Oxygenase from Mesorhizobium loti MAFF303099 and Its Mechanistic Implications

    SciTech Connect

    McCulloch, Kathryn M.; Mukherjee, Tathagata; Begley, Tadhg P.; Ealick, Steven E.; Cornell

    2009-06-12

    A vitamin B{sub 6} degradative pathway has recently been identified and characterized in Mesorhizobium loti MAFF303099. One of the enzymes on this pathway, 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase (MHPCO), is a flavin-dependent enzyme and catalyzes the oxidative ring-opening of 2-methyl-3-hydroxypyridine-5-carboxylic acid to form E-2-(acetamino-methylene)succinate. The gene for this enzyme has been cloned, and the corresponding protein has been overexpressed in Escherichia coli and purified. The crystal structure of MHPCO has been solved to 2.1 {angstrom} using SAD phasing with and without the substrate MHPC bound. These crystal structures provide insight into the reaction mechanism and suggest roles for active site residues in the catalysis of a novel oxidative ring-opening reaction.

  12. Origin of Epilachnapaenulata defensive alkaloids: incorporation of [1-13C]-sodium acetate and [methyl-2H3]-stearic acid.

    PubMed

    Camarano, S; González, A; Rossini, C

    2012-01-01

    Ladybird beetles produce a large number of defensive alkaloids. Previous studies suggest that the structural diversity of these endogenous alkaloids can be traced to a common biosynthetic route based on the condensation of several acetate units. In this study, adults of Epilachna paenulata, a phytophagous neotropical species, were fed on diet enriched with potential precursors (sodium acetate, fatty acids and the amino acids lysine and ornithine) labeled with stable isotopes ((13)C, (2)H and (15)N). Labeled acetate was incorporated into the structurally related homotropane and piperidine alkaloids. The later also showed incorporation of [methyl-(2)H3] stearic acid. Our results hence support a fatty acid pathway for the biosynthesis of E. paenulata alkaloids. To our knowledge, this is the first report on the incorporation of a labeled fatty acid into a defensive piperidine alkaloid in insects.

  13. A library synthesis of 4-hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester derivatives as anti-tumor agents.

    PubMed

    Hayakawa, Ichiro; Shioya, Rieko; Agatsuma, Toshinori; Furukawa, Hidehiko; Naruto, Shunji; Sugano, Yuichi

    2004-09-06

    As a result of a hit-to-lead program using a technique of solution-phase parallel synthesis, a highly potent (2,4-dimethoxyphenyl)-[6-(3-fluorophenyl)-4-hydroxy-3-methylbenzofuran-2-yl]methanone (15b) was synthesized as an optimized derivative of 4-hydroxy-3-methyl-6-phenylbenzofuran-2-carboxylic acid ethyl ester (1), which was discovered as a screening hit from small-molecule libraries and exhibited selective cytotoxicity against a tumorigenic cell line.

  14. Unique Honey Bee (Apis mellifera) Hive Component-Based Communities as Detected by a Hybrid of Phospholipid Fatty-Acid and Fatty-Acid Methyl Ester Analyses

    PubMed Central

    2015-01-01

    Microbial communities (microbiomes) are associated with almost all metazoans, including the honey bee Apis mellifera. Honey bees are social insects, maintaining complex hive systems composed of a variety of integral components including bees, comb, propolis, honey, and stored pollen. Given that the different components within hives can be physically separated and are nutritionally variable, we hypothesize that unique microbial communities may occur within the different microenvironments of honey bee colonies. To explore this hypothesis and to provide further insights into the microbiome of honey bees, we use a hybrid of fatty acid methyl ester (FAME) and phospholipid-derived fatty acid (PLFA) analysis to produce broad, lipid-based microbial community profiles of stored pollen, adults, pupae, honey, empty comb, and propolis for 11 honey bee hives. Averaging component lipid profiles by hive, we show that, in decreasing order, lipid markers representing fungi, Gram-negative bacteria, and Gram-positive bacteria have the highest relative abundances within honey bee colonies. Our lipid profiles reveal the presence of viable microbial communities in each of the six hive components sampled, with overall microbial community richness varying from lowest to highest in honey, comb, pupae, pollen, adults and propolis, respectively. Finally, microbial community lipid profiles were more similar when compared by component than by hive, location, or sampling year. Specifically, we found that individual hive components typically exhibited several dominant lipids and that these dominant lipids differ between components. Principal component and two-way clustering analyses both support significant grouping of lipids by hive component. Our findings indicate that in addition to the microbial communities present in individual workers, honey bee hives have resident microbial communities associated with different colony components. PMID:25849080

  15. Analysis of salicylic acid-dependent pathways in Arabidopsis thaliana following infection with Plasmodiophora brassicae and the influence of salicylic acid on disease.

    PubMed

    Lovelock, David A; Šola, Ivana; Marschollek, Sabine; Donald, Caroline E; Rusak, Gordana; van Pée, Karl-Heinz; Ludwig-Müller, Jutta; Cahill, David M

    2016-10-01

    Salicylic acid (SA) biosynthesis, the expression of SA-related genes and the effect of SA on the Arabidopsis-Plasmodiophora brassicae interaction were examined. Biochemical analyses revealed that, in P. brassicae-infected Arabidopsis, the majority of SA is synthesized from chorismate. Real-time monitored expression of a gene for isochorismate synthase was induced on infection. SA can be modified after accumulation, either by methylation, improving its mobility, or by glycosylation, as one possible reaction for inactivation. Quantitative reverse transcription-polymerase chain reaction (qPCR) confirmed the induction of an SA methyltransferase gene, whereas SA glucosyltransferase expression was not changed after infection. Col-0 wild-type (wt) did not provide a visible phenotypic resistance response, whereas the Arabidopsis mutant dnd1, which constitutively activates the immune system, showed reduced gall scores. As dnd1 showed control of the pathogen, exogenous SA was applied to Arabidopsis in order to test whether it could suppress clubroot. In wt, sid2 (SA biosynthesis), NahG (SA-deficient) and npr1 (SA signalling-impaired) mutants, SA treatment did not alter the gall score, but positively affected the shoot weight. This suggests that SA alone is not sufficient for Arabidopsis resistance against P. brassicae. Semi-quantitative PCR revealed that wt, cpr1, dnd1 and sid2 showed elevated PR-1 expression on P. brassicae and SA + P. brassicae inoculation at 2 and 3 weeks post-inoculation (wpi), whereas NahG and npr1 showed no expression. This work contributes to the understanding of SA involvement in the Arabidopsis-P. brassicae interaction.

  16. The effects of omega-3 polyunsaturated fatty acids and genetic variants on methylation levels of the interleukin-6 gene promoter

    PubMed Central

    Ma, Yiyi; Smith, Caren E.; Lai, Chao-Qiang; Irvin, Marguerite R.; Parnell, Laurence D.; Lee, Yu-Chi; Pham, Lucia D.; Aslibekyan, Stella; Claas, Steven A.; Tsai, Michael Y.; Borecki, Ingrid B.; Kabagambe, Edmond K.; Ordovás, José M.; Absher, Devin M.; Arnett, Donna K.

    2016-01-01

    Scope Omega-3 PUFAs (n-3 PUFAs) reduce IL-6 gene expression, but their effects on transcription regulatory mechanisms are unknown. We aimed to conduct an integrated analysis with both population and in vitro studies to systematically explore the relationships among n-3 PUFA, DNA methylation, single nucleotide polymorphisms (SNPs), gene expression, and protein concentration of IL6. Methods and results Using data in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study and the Encyclopedia of DNA Elements (ENCODE) consortium, we found that higher methylation of IL6 promoter cg01770232 was associated with higher IL-6 plasma concentration (p = 0.03) and greater IL6 gene expression (p = 0.0005). Higher circulating total n-3 PUFA was associated with lower cg01770232 methylation (p = 0.007) and lower IL-6 concentration (p = 0.02). Moreover, an allele of IL6 rs2961298 was associated with higher cg01770232 methylation (p = 2.55 × 10−7). The association between n-3 PUFA and cg01770232 methylation was dependent on rs2961298 genotype (p = 0.02), but higher total n-3 PUFA was associated with lower cg01770232 methylation in the heterozygotes (p = 0.04) not in the homozygotes. Conclusion Higher n-3 PUFA is associated with lower methylation at IL6 promoter, which may be modified by IL6 SNPs. PMID:26518637

  17. Human GAPDH Is a Target of Aspirin's Primary Metabolite Salicylic Acid and Its Derivatives.

    PubMed

    Choi, Hyong Woo; Tian, Miaoying; Manohar, Murli; Harraz, Maged M; Park, Sang-Wook; Schroeder, Frank C; Snyder, Solomon H; Klessig, Daniel F

    2015-01-01

    The plant hormone salicylic acid (SA) controls several physiological processes and is a key regulator of multiple levels of plant immunity. To decipher the mechanisms through which SA's multiple physiological effects are mediated, particularly in immunity, two high-throughput screens were developed to identify SA-binding proteins (SABPs). Glyceraldehyde 3-Phosphate Dehydrogenase (GAPDH) from plants (Arabidopsis thaliana) was identified in these screens. Similar screens and subsequent analyses using SA analogs, in conjunction with either a photoaffinity labeling technique or surface plasmon resonance-based technology, established that human GAPDH (HsGAPDH) also binds SA. In addition to its central role in glycolysis, HsGAPDH participates in several pathological processes, including viral replication and neuronal cell death. The anti-Parkinson's drug deprenyl has been shown to suppress nuclear translocation of HsGAPDH, an early step in cell death and the resulting cell death induced by the DNA alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine. Here, we demonstrate that SA, which is the primary metabolite of aspirin (acetyl SA) and is likely responsible for many of its pharmacological effects, also suppresses nuclear translocation of HsGAPDH and cell death. Analysis of two synthetic SA derivatives and two classes of compounds from the Chinese medicinal herb Glycyrrhiza foetida (licorice), glycyrrhizin and the SA-derivatives amorfrutins, revealed that they not only appear to bind HsGAPDH more tightly than SA, but also exhibit a greater ability to suppress translocation of HsGAPDH to the nucleus and cell death.

  18. Negative polarity of phenyl-C{sub 61} butyric acid methyl ester adjacent to donor macromolecule domains

    SciTech Connect

    Alley, Olivia J.; Dawidczyk, Thomas J.; Hardigree, Josué F. Martínez; Katz, Howard E.; Wu, Meng-Yin; Johns, Gary L.; Markovic, Nina; Arnold, Michael S.

    2015-01-19

    Interfacial fields within organic photovoltaics influence the movement of free charge carriers, including exciton dissociation and recombination. Open circuit voltage (V{sub oc}) can also be dependent on the interfacial fields, in the event that they modulate the energy gap between donor HOMO and acceptor LUMO. A rise in the vacuum level of the acceptor will increase the gap and the V{sub oc}, which can be beneficial for device efficiency. Here, we measure the interfacial potential differences at donor-acceptor junctions using Scanning Kelvin Probe Microscopy, and quantify how much of the potential difference originates from physical contact between the donor and acceptor. We see a statistically significant and pervasive negative polarity on the phenyl-C{sub 61} butyric acid methyl ester (PCBM) side of PCBM/donor junctions, which should also be present at the complex interfaces in bulk heterojunctions. This potential difference may originate from molecular dipoles, interfacial interactions with donor materials, and/or equilibrium charge transfer due to the higher work function and electron affinity of PCBM. We show that the contact between PCBM and poly(3-hexylthiophene) doubles the interfacial potential difference, a statistically significant difference. Control experiments determined that this potential difference was not due to charges trapped in the underlying substrate. The direction of the observed potential difference would lead to increased V{sub oc}, but would also pose a barrier to electrons being injected into the PCBM and make recombination more favorable. Our method may allow unique information to be obtained in new donor-acceptor junctions.

  19. Photophysics and morphology of poly (3-dodecylthienylenevinylene)-[6,6]-phenyl-C{sub 61}-butyric acid methyl ester composite

    SciTech Connect

    Lafalce, E.; Toglia, P.; Jiang, X.; Zhang, C.

    2012-05-21

    A series of low band gap poly(3-dodecylthienylenevinylene) (PTV) with controlled morphological order have been synthesized and blended with the electron acceptor [6,6]-phenyl-C{sub 61}-butyric acid methyl ester (PCBM) for organic photovoltaic devices. Two polymers with the most and least side chain regioregularity were chosen in this work, namely the PTV010 and PTV55, respectively. Using photoluminescence, photo-induced absorption spectroscopy, and atomic force microscopy, we find no direct evidence of photoinduced charge transfer between the two constituents, independent of the bulk-heterojunction morphology of the film, although the possibility of formation of P{sup +}/C{sub 60}{sup -} charge transfer complex was not completely ruled out. The large exciton binding energy (E{sub b} = 0.6 eV) in PTV inhibits the photoinduced electron transfer from PTV to PCBM. In addition, excitons formed on polymer chains suffer ultrafast (

  20. Isolation and characterization of a novel 2-methyl-4-chlorophenoxyacetic acid-degrading Enterobacter sp. strain SE08.

    PubMed

    Tan, Lin; Hu, Qiulong; Xiong, Xingyao; Su, Xiaojun; Huang, Yanning; Jiang, Ziwei; Zhou, Qingming; Zhao, Songyi; Zeng, Wei-ai

    2013-10-01

    A bacterial strain (SE08) capable of utilizing 2-methyl-4-chlorophenoxy acetic acid (MCPA) as the sole carbon and energy source for growth was isolated by continuous enrichment culturing in minimal salt medium (MSM) from a long term MCPA exposed soil. This bacterial strain was identified as Enterobacter sp. based on morphological, physiological and biochemical tests, as well as 16S rRNA sequence analysis. Its ability to degrade MCPA was determined using high performance liquid chromatography. The strain SE08 can tolerate unusually high MCPA concentrations (125-2000mg/L). The influences of culturing factors (initial concentration, pH, and temperature) on the bacterial growth and substrate degradation were studied. The results showed that the optimal MCPA degradation occurred at an MCPA concentration of 500mg/L, 30°C and pH 6.0. Under these conditions, 68.5 percent of MCPA in MSM was degraded by SE08, and the OD600nm reached 0.64 after culturing for 72h. The degradation of MCPA could be enhanced by addition of both carbon and nitrogen sources. At an initial MCPA concentration of 500mg/L, when 5g/L glucose and 2.5g/L yeast extract were added into the MSM media, the MCPA degradation was significantly increased to 83.8 percent, and OD600nm was increased to 1.09 after incubation at 30°C and pH 6.0 for 72h. This is the first study showing that an Enterobacter sp. strain is capable of degrading MCPA, which might provide a new approach for the remediation of MCPA contaminated soil and contribute to the limited knowledge about the function of Enterobacter species.

  1. The antifungal activity of the cuticular and internal fatty acid methyl esters and alcohols in Calliphora vomitoria.

    PubMed

    Gołębiowski, Marek; Cerkowniak, Magdalena; Dawgul, Małgorzata; Kamysz, Wojciech; Boguś, Mieczysława I; Stepnowski, Piotr

    2013-07-01

    SUMMARY The composition of the fatty acid methyl ester (FAME) and alcohol fractions of the cuticular and internal lipids of Calliphora vomitoria larvae, pupae and male/female adults was obtained by separating these two fractions by HPLC-LLSD and analysing them quantitatively using GC-MS. Analysis of the cuticular lipids of the worldwide, medically important ectoparasite C. vomitoria revealed 6 FAMEs with odd-numbered carbon chains from C15:0 to C19:0 in the larvae, while internal lipids contained 9 FAMEs ranging from C15:1 to C19:0. Seven FAMEs from C15:0 to C19:0 were identified in the cuticular lipids of the pupae, whereas the internal lipids of the pupae contained 10 FAMEs from C13:0 to C19:0. The cuticular lipids of males and females and also the internal lipids of males contained 5, 7 and 6 FAMEs from C15:0 to C19:0 respectively. Seven FAMEs from C13:0 to C19:0 were identified in the internal lipids of females, and 7, 6, 5 and 3 alcohols were found in the cuticular lipids of larvae, pupae, males and females respectively. Only saturated alcohols with even-numbered carbon chains were present in these lipids. Only 1 alcohol (C22:0) was detected in the internal lipids of C. vomitoria larvae, while just 4 alcohols from - C18:0 to C24:0 - were identified in the internal lipids of pupae, and males and females. We also identified glycerol and cholesterol in the larvae, pupae, males and females of C. vomitoria. The individual alcohols and FAMEs, as well as their mixtures isolated from the cuticular and internal lipids of larvae, pupae, males and females of C. vomitoria, demonstrated antimicrobial activity against entomopathogenic fungi.

  2. Adolescent social defeat alters N-methyl-D-aspartic acid receptor expression and impairs fear learning in adulthood.

    PubMed

    Novick, Andrew M; Mears, Mackenzie; Forster, Gina L; Lei, Yanlin; Tejani-Butt, Shanaz M; Watt, Michael J

    2016-05-01

    Repeated social defeat of adolescent male rats results in adult mesocortical dopamine hypofunction, impaired working memory, and increased contextual anxiety-like behavior. Given the role of glutamate in dopamine regulation, cognition, and fear and anxiety, we investigated potential changes to N-methyl-D-aspartic acid (NMDA) receptors following adolescent social defeat. As both NMDA receptors and mesocortical dopamine are implicated in the expression and extinction of conditioned fear, a separate cohort of rats was challenged with a classical fear conditioning paradigm to investigate whether fear learning is altered by adolescent defeat. Quantitative autoradiography was used to measure 3H-MK-801 binding to NMDA receptors in regions of the medial prefrontal cortex, caudate putamen, nucleus accumbens, amygdala and hippocampus. Assessment of fear learning was achieved using an auditory fear conditioning paradigm, with freezing toward the auditory tone used as a measure of conditioned fear. Compared to controls, adolescent social defeat decreased adult NMDA receptor expression in the infralimbic region of the prefrontal cortex and central amygdala, while increasing expression in the CA3 region of the hippocampus. Previously defeated rats also displayed decreased conditioned freezing during the recall and first extinction periods, which may be related to the observed decreases and increases in NMDA receptors within the central amygdala and CA3, respectively. The alteration in NMDA receptors seen following adolescent social defeat suggests that dysfunction of glutamatergic systems, combined with mesocortical dopamine deficits, likely plays a role in the some of the long-term behavioral consequences of social stressors in adolescence seen in both preclinical and clinical studies.

  3. Profiling and Quantifying Differential Gene Transcription Provide Insights into Ganoderic Acid Biosynthesis in Ganoderma lucidum in Response to Methyl Jasmonate

    PubMed Central

    Shi, Liang; Mu, Da-Shuai; Jiang, Ai-Liang; Han, Qin; Zhao, Ming-Wen

    2013-01-01

    Ganoderma lucidum is a mushroom with traditional medicinal properties that has been widely used in China and other countries in Eastern Asia. Ganoderic acids (GA) produced by G. lucidum exhibit important pharmacological activities. Previous studies have demonstrated that methyl jasmonate (MeJA) is a potent inducer of GA biosynthesis and the expression of genes involved in the GA biosynthesis pathway in G. lucidum. To further explore the mechanism of GA biosynthesis, cDNA-Amplified Fragment Length Polymorphism (cDNA-AFLP) was used to identify genes that are differentially expressed in response to MeJA. Using 64 primer combinations, over 3910 transcriptionally derived fragments (TDFs) were obtained. Reliable sequence data were obtained for 390 of 458 selected TDFs. Ninety of these TDFs were annotated with known functions through BLASTX searching the GenBank database, and 12 annotated TDFs were assigned into secondary metabolic pathways by searching the KEGGPATHWAY database. Twenty-five TDFs were selected for qRT-PCR analysis to confirm the expression patterns observed with cDNA-AFLP. The qRT-PCR results were consistent with the altered patterns of gene expression revealed by the cDNA-AFLP technique. Additionally, the transcript levels of 10 genes were measured at the mycelium, primordia, and fruiting body developmental stages of G. lucidum. The greatest expression levels were reached during primordia for all of the genes except cytochrome b2 reached its highest expression level in the mycelium stage. This study not only identifies new candidate genes involved in the regulation of GA biosynthesis but also provides further insight into MeJA-induced gene expression and secondary metabolic response in G. lucidum. PMID:23762280

  4. Salvianolic acid B-induced microRNA-152 inhibits liver fibrosis by attenuating DNMT1-mediated Patched1 methylation.

    PubMed

    Yu, Fujun; Lu, Zhongqiu; Chen, Bicheng; Wu, Xiaoli; Dong, Peihong; Zheng, Jianjian

    2015-11-01

    Epithelial-mesenchymal transition (EMT) was reported to be involved in the activation of hepatic stellate cells (HSCs), contributing to the development of liver fibrosis. Epithelial-mesenchymal transition can be promoted by the Hedgehog (Hh) pathway. Patched1 (PTCH1), a negative regulatory factor of the Hh signalling pathway, was down-regulated during liver fibrosis and associated with its hypermethylation status. MicroRNAs (miRNAs) are reported to play a critical role in the control of various HSCs functions. However, miRNA-mediated epigenetic regulations in EMT during liver fibrosis are seldom studied. In this study, Salvianolic acid B (Sal B) suppressed the activation of HSCs in CCl4 -treated mice and mouse primary HSCs, leading to inhibition of cell proliferation, type I collagen and alpha-smooth muscle actin. We demonstrated that the antifibrotic effects caused by Sal B were, at least in part, via inhibition of EMT and the Hh pathway. In particular, up-regulation of PTCH1 was associated with decreased DNA methylation level after Sal B treatment. Accordingly, DNA methyltransferase 1 (DNMT1) was attenuated by Sal B in vivo and in vitro. The knockdown of DNMT1 in Sal B-treated HSCs enhanced PTCH1 expression and its demethylation level. Interestingly, increased miR-152 in Sal B-treated cells was responsible for the hypomethylation of PTCH1 by Sal B. As confirmed by the luciferase activity assay, DNMT1 was a direct target of miR-152. Further studies showed that the miR-152 inhibitor reversed Sal B-mediated PTCH1 up-regulation and DNMT1 down-regulation. Collectively, miR-152 induced by Sal B, contributed to DNMT1 down-regulation and epigenetically regulated PTCH1, resulting in the inhibition of EMT in liver fibrosis.

  5. Salvianolic acid B-induced microRNA-152 inhibits liver fibrosis by attenuating DNMT1-mediated Patched1 methylation

    PubMed Central

    Yu, Fujun; Lu, Zhongqiu; Chen, Bicheng; Wu, Xiaoli; Dong, Peihong; Zheng, Jianjian

    2015-01-01

    Epithelial-mesenchymal transition (EMT) was reported to be involved in the activation of hepatic stellate cells (HSCs), contributing to the development of liver fibrosis. Epithelial-mesenchymal transition can be promoted by the Hedgehog (Hh) pathway. Patched1 (PTCH1), a negative regulatory factor of the Hh signalling pathway, was down-regulated during liver fibrosis and associated with its hypermethylation status. MicroRNAs (miRNAs) are reported to play a critical role in the control of various HSCs functions. However, miRNA-mediated epigenetic regulations in EMT during liver fibrosis are seldom studied. In this study, Salvianolic acid B (Sal B) suppressed the activation of HSCs in CCl4-treated mice and mouse primary HSCs, leading to inhibition of cell proliferation, type I collagen and alpha-smooth muscle actin. We demonstrated that the antifibrotic effects caused by Sal B were, at least in part, via inhibition of EMT and the Hh pathway. In particular, up-regulation of PTCH1 was associated with decreased DNA methylation level after Sal B treatment. Accordingly, DNA methyltransferase 1 (DNMT1) was attenuated by Sal B in vivo and in vitro. The knockdown of DNMT1 in Sal B-treated HSCs enhanced PTCH1 expression and its demethylation level. Interestingly, increased miR-152 in Sal B-treated cells was responsible for the hypomethylation of PTCH1 by Sal B. As confirmed by the luciferase activity assay, DNMT1 was a direct target of miR-152. Further studies showed that the miR-152 inhibitor reversed Sal B-mediated PTCH1 up-regulation and DNMT1 down-regulation. Collectively, miR-152 induced by Sal B, contributed to DNMT1 down-regulation and epigenetically regulated PTCH1, resulting in the inhibition of EMT in liver fibrosis. PMID:26257392

  6. Structural, optical, thermal and mechanical characterization of an organic nonlinear optical material: 4-methyl-3-nitrobenzoic acid single crystal

    NASA Astrophysics Data System (ADS)

    Bharathi, M. Divya; Ahila, G.; Mohana, J.; Chakkaravarthi, G.; Anbalagan, G.

    2016-11-01

    Organic single crystals of 4-methyl-3-nitrobenzoic acid (4M3N) have been grown by slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction study reveals that 4M3N crystallizes in monoclinic system with space group P21/n. The crystalline perfection of the crystal was analyzed by high resolution X-ray diffraction (HRXRD) measurements. The functional groups present in 4M3N have been identified from FT-IR and FT-Raman spectra. The lower cut-off wavelength of 4M3N is found to be 404 nm and the optical band gap is calculated as 2.91 eV. The refractive index shows normal behavior with wavelength. The physio chemical changes, decomposition and stability of the 4M3N compound were established by TG-DTA studies. Vickers microhardness measurement concludes that 4M3N belongs to soft material (n=2.5) category. The LDT value is found to be higher than that of KDP and some of the important organic NLO materials. The third order nonlinear refractive index and nonlinear absorption coefficient of the 4M3N have been measured by Z-scan studies. The imaginary and real parts of the third-order susceptibility values were determined as Im χ3=9.129×10-11 esu and Re χ3=1.4034×10-9 esu respectively. The dislocation density was calculated to be 3.0448×106 cm-2 which indicates the quality of the crystal.

  7. 75 FR 11740 - S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1-cyclohex-2-enyl)-3-methyl-penta-(2Z,4E...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... AGENCY 40 CFR Part 180 S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1- cyclohex-2-enyl)-3-methyl-penta-(2Z,4E)-dienoic Acid; Amendment to an Exemption from the Requirement of a Tolerance AGENCY... exemption from the requirement of a tolerance for residues of the biochemical pesticide S-Abscisic Acid,...

  8. Mercury methylation in Sphagnum moss mats and its association with sulfate-reducing bacteria in an acidic Adirondack forest lake wetland.

    PubMed

    Yu, Ri-Qing; Adatto, Isaac; Montesdeoca, Mario R; Driscoll, Charles T; Hines, Mark E; Barkay, Tamar

    2010-12-01

    Processes leading to the bioaccumulation of methylmercury (MeHg) in northern wetlands are largely unknown. We have studied various ecological niches within a remote, acidic forested lake ecosystem in the southwestern Adirondacks, NY, to discover that mats comprised of Sphagnum moss were a hot spot for mercury (Hg) and MeHg accumulation (190.5 and 18.6 ng g⁻¹ dw, respectively). Furthermore, significantly higher potential methylation rates were measured in Sphagnum mats as compared with other sites within Sunday Lake's ecosystem. Although MPN estimates showed a low biomass of sulfate-reducing bacteria (SRB), 2.8 × 10⁴ cells mL⁻¹ in mat samples, evidence consisting of (1) a twofold stimulation of potential methylation by the addition of sulfate, (2) a significant decrease in Hg methylation in the presence of the sulfate reduction inhibitor molybdate, and (3) presence of dsrAB-like genes in mat DNA extracts, suggested that SRB were involved in Hg methylation. Sequencing of dsrB genes indicated that novel SRB, incomplete oxidizers including Desulfobulbus spp. and Desulfovibrio spp., and syntrophs dominated the sulfate-reducing guild in the Sphagnum moss mat. Sphagnum, a bryophyte dominating boreal peatlands, and its associated microbial communities appear to play an important role in the production and accumulation of MeHg in high-latitude ecosystems.

  9. High-performance liquid chromatography and nuclear magnetic resonance study of linear tetrapeptides and octapeptides containing N-methylated amino acid residues.

    PubMed

    Sýkora, David; Záková, Lenka; Budesínský, Milos

    2007-08-10

    Chromatographic behavior of a series of N-methylated tetra and octapeptides on a reversed-phase sorbent was studied considering the information obtained on these compounds by NMR spectroscopy. The modified tetrapeptides were derived from GFFY-NH2, GFFF-NH2 and GFFH-NH2 primary structures by N-methylation at various peptide bond positions. Similarly, the N-methylated octapeptides were based on TPK(Pac)T C-terminally elongated forms of GFFY and GFFF. It was found that many studied N-methylated peptides provide broad peaks as a consequence of cis/trans isomerism of the R1CON(CH3)R2 peptide bond. The extent of the peak spreading depends on the following important factors: the nature of the surrounding amino acid residues, the location of the modified peptide bond within the peptide chain, temperature, and mobile phase flow-rate. All these aspects were critically evaluated. Nearly complete separation of the individual conformers of GF(NMe)FY-NH2 was obtained applying fast chromatography on short column packed with 20-30 microm reversed-phase sorbent.

  10. Eight boreal wetlands as sources and sinks for methyl mercury in relation to soil acidity, C/N ratio, and small-scale flooding.

    PubMed

    Tjerngren, Ida; Meili, Markus; Björn, Erik; Skyllberg, Ulf

    2012-08-07

    Four years of catchment export and wetland input-output mass balances are reported for inorganic Hg (Hg(inorg)), methyl mercury (MeHg), dissolved organic carbon (DOC), and sulfate in eight Swedish boreal wetlands. All wetlands had a history of artificial drainage and seven were subjected to small-scale flooding during the complete study period (two sites) or the two last years (five sites). We used an approach in which specific runoff data determined at hydrological stations situated at a distance from the studied sites were used in the calculation of water and element budgets. All wetlands except one were significant sinks for Hg(inorg). Seven wetlands were consistent sources of MeHg and one (an Alnus glutinosa swamp) was a significant sink. The pattern of MeHg yields was in good agreement with previously determined methylation and demethylation rates in the wetland soils of this study, with a maximum MeHg yield obtained in wetlands with an intermediate soil acidity (pH ∼5.0) and C/N ratio (∼20). We hypothesize that an increased nutrient status from poor to intermediate conditions promotes methylation over demethylation, whereas a further increase in nutrient status and trophy to meso- and eutrophic conditions promotes demethylation over methylation. Small-scale flooding showed no or moderate changes in MeHg yield, maintaining differences among wetlands related to nutrient status.

  11. Emissions from diesel engines using fatty acid methyl esters from different vegetable oils as blends and pure fuel

    NASA Astrophysics Data System (ADS)

    Schröder, O.; Munack, A.; Schaak, J.; Pabst, C.; Schmidt, L.; Bünger, J.; Krahl, J.

    2012-05-01

    Biodiesel is used as a neat fuel as well as in blends with mineral diesel fuel. Because of the limited availability of fossil resources, an increase of biogenic compounds in fuels is desired. To achieve this goal, next to rapeseed oil, other sustainably produced vegetable oils can be used as raw materials. These raw materials influence the fuel properties as well as the emissions. To investigate the environmental impact of the exhaust gas, it is necessary to determine regulated and non-regulated exhaust gas components. In detail, emissions of aldehydes and polycyclic aromatic hydrocarbons (PAH), as well as mutagenicity in the Ames test are of special interest. In this paper emission measurements on a Euro III engine OM 906 of Mercedes-Benz are presented. As fuel vegetable oil methyl esters from various sources and reference diesel fuel were used as well as blends of the vegetable oil methyl esters with diesel fuel. PAH were sampled according to VDI Guideline 3872. The sampling procedure of carbonyls was accomplished using DNPH cartridges coupled with potassium iodide cartridges. The carbon monoxide and hydrocarbon emissions of the tested methyl esters show advantages over DF. The particle mass emissions of methyl esters were likewise lower than those of DF, only linseed oil methyl ester showed higher particle mass emissions. A disadvantage is the use of biodiesel with respect to emissions of nitrogen oxides. They increased depending on the type of methyl ester by 10% to 30%. Emissions of polycyclic aromatic hydrocarbons (PAHs) and the results of mutagenicity tests correlate with those of the PM measurements, at which for palm oil methyl ester next to coconut oil methyl ester the lowest emissions were detected. From these results one can formulate a clear link between the iodine number of the ester and the emission behaviour. For blends of biodiesel and diesel fuel, emissions changed linearly with the proportion of biodiesel. However, especially in the non

  12. One-pot synthesis of biocompatible boronic acid-functionalized poly(methyl methacrylate) nanoparticles at sub-100 nm scale for glucose sensing

    NASA Astrophysics Data System (ADS)

    Sakalak, Huseyin; Ulasan, Mehmet; Yavuz, Emine; Camli, Sevket Tolga; Yavuz, Mustafa Selman

    2014-12-01

    Poly(methyl methacrylate) nanoparticles containing 4-vinylphenyl boronic acid were synthesized in one pot by surfactant-free emulsion polymerization. The nanoparticles were characterized by scanning electron microscopy and dynamic light scattering. Boron content in the nanoparticles was confirmed by electron-dispersive X-ray spectroscopy. In polymerization process, several co-monomer ratios were studied in order to obtain optimum nanoparticle size. Average hydrodynamic diameter and polydispersity index of nanoparticles versus variation of acetone percentage in the solvent mixture and total monomer concentration were investigated. The effect of boronic acid concentration in the monomer mixture on nanoparticle size and size distribution was also reported. Without further functionalization to the nanoparticles, the catechol dye, alizarin red S, was bound to boronic acid-containing nanoparticles. These nanoparticles behave as a nanosensor by which glucose or fructose can be easily detected. Dye-containing nanoparticles were undertaken displacement reaction by glucose or fructose. The glucose or fructose content was also monitored by UV-Visible spectrophotometer. Furthermore, cytotoxicity studies of boronic acid-carrying poly(methyl methacrylate) nanoparticles were carried out in 3T3 cells, which showed no toxicity effect on the cells.

  13. Pressure Dependence of the Acid/Base Equilibria of Methyl Orange in Aqueous Solutions to 1000 bars at 20°C

    SciTech Connect

    Suleimenov, Oleg M; Boily, Jean F

    2006-07-31

    The pressure dependence on the acid/base equilibria of methyl orange in aqueous solution was measured at 20°C in the 1-1000 bar range with a newly designed flow-through spectrophotometric cell. Combined chemometric and thermodynamic analyses of uv-vis spectrophotometric data were used to extract the dissociation constants as well as the changes in molar volume and isothermal compressibility of methyl orange as a function of pressure. The results show increasing pressure promotes the deprotonation of the methyl orange, with pK values ranging from 3.505 at 1 bar to 3.445 (0.002) at 1000 bars. Increasing pressure also yields small values of negative changes in the molar volume ranging from –6.9 cm3∙mol-1 at 1 bar to –1.7 cm3∙mol-1 at 1000 bars. The isothermal compressibility of methyl orange in this pressure range was estimated using the 2nd derivative of 2nd and 3rd order polynomial fits to the constants and gave rise to a constant value of –48.4x 10-4 cm3∙mol-1∙bar-1 in the former case, and increasing values from -107×10-4 cm3∙mol-1∙bar-1 at 1 bar to 3.43×10-4 cm3∙mol-1∙bar-1 at 1000 bars in the latter case. Molar absorption coefficients for the protonated and deprotonated species were also shown to be only slightly affected by pressure changes and can be used to accurately predict the absorption spectra of methyl orange as a function of pressure.

  14. Novel opioid peptide derived antagonists containing (2S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2S)-Mdcp].

    PubMed

    Ghosh, Animesh; Luo, Jie; Liu, Chen; Weltrowska, Grazyna; Lemieux, Carole; Chung, Nga N; Lu, Yixin; Schiller, Peter W

    2008-09-25

    A synthesis of the novel tyrosine analogue (2 S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2 S)-Mdcp] (15) was developed. In (2 S)-Mdcp, the amino and hydroxyl groups of 2',6'-dimethyltyrosine are replaced by a methyl and a carbamoyl group, respectively, and its substitution for Tyr (1) in opioid agonist peptides resulted in compounds showing antagonism at all three opioid receptors. The cyclic peptide (2 S)-Mdcp-c[D-Cys-Gly-Phe(pNO 2)-D-Cys]NH 2 (1) was a potent and selective mu antagonist, whereas (2 S)-Mdcp-c[D-Pen-Gly-Phe(pF)-Pen]-Phe-OH (3) showed subnanomolar delta antagonist activity and extraordinary delta selectivity.

  15. Dual-Responsive pH and Temperature Sensitive Nanoparticles Based on Methacrylic Acid and Di(ethylene glycol) Methyl Ether Methacrylate for the Triggered Release of Drugs.

    PubMed

    Khine, Yee Yee; Jiang, Yanyan; Dag, Aydan; Lu, Hongxu; Stenzel, Martina H

    2015-08-01

    A series of thermo-and pH-responsive poly(methyl methacrylate)-block-poly[methacrylic acid-co-di(ethylene glycol) methyl ether methacrylate] PMMA-b-P[MAA-co-DEGMA] block copolymers were synthesized by RAFT polymerization and self-assembled into micelles. The molar ratio of MAA was altered from 0-12% in order to modulate the lower critical solution temperature (LCST) of PDEGMA. The release of the drug albendazole from the micelle was strongly dependent on the temperature and the LCST value of the polymer. Systems below the LCST released the drug slowly while increasing the temperature above the LCST or decreasing the pH value to 5 resulted in the burst-like release of the drug. ABZ delivered in this pH-responsive drug carrier had a higher toxicity than the free drug or the drug delivered in a non-responsive drug carrier.

  16. Genetic Analysis of Natural Variation in Antirrhinum Scent Profiles Identifies BENZOIC ACID CARBOXYMETHYL TRANSFERASE As the Major Locus Controlling Methyl Benzoate Synthesis

    PubMed Central

    Ruiz-Hernández, Victoria; Hermans, Benjamin; Weiss, Julia; Egea-Cortines, Marcos

    2017-01-01

    The Antirrhinum genus has a considerable complexity in the scent profiles produced by different species. We have analyzed the genetic differences between A. majus and A. linkianum, two species divergent in the emission of methyl benzoate, methyl cinnamate, acetophenone, and ocimene. The genetic analysis showed that all compounds segregated in a Mendelian fashion attributable to one or two loci with simple or epistatic interactions. Several lines lacked methyl benzoate, a major Volatile Organic Compound emitted by A. majus but missing in A. linkianum. Using a candidate gene approach, we found that the BENZOIC ACID CARBOXYMETHYL TRANSFERASE from A. linkianum appeared to be a null allele as we could not detect mRNA expression. The coding region did not show significant differences that could explain the loss of expression. The intron-exon boundaries was also conserved indicating that there is no alternative splicing in A. linkianum as compared to A. majus. However, it showed multiple polymorphisms in the 5′ promoter region including two insertions, one harboring an IDLE MITE transposon with additional sequences with high homology to the PLENA locus and a second one with somewhat lower homology to the regulatory region of the VENOSA locus. It also had a 778 bp deletion as compared to the A. majus BAMT promoter region. Our results show that the differences in scent emission between A. majus and A. linkianum may be traced back to single genes involved in discrete biosynthetic reactions such as benzoic acid methylation. Thus, natural variation of this complex trait maybe the result of combinations of wild type, and loss of function alleles in different genes involved in discrete VOCs biosynthesis. Furthermore, the presence of active transposable elements in the genus may account for rapid evolution and instability, raising the possibility of adaptation to local pollinators. PMID:28154577

  17. Genetic Analysis of Natural Variation in Antirrhinum Scent Profiles Identifies BENZOIC ACID CARBOXYMETHYL TRANSFERASE As the Major Locus Controlling Methyl Benzoate Synthesis.

    PubMed

    Ruiz-Hernández, Victoria; Hermans, Benjamin; Weiss, Julia; Egea-Cortines, Marcos

    2017-01-01

    The Antirrhinum genus has a considerable complexity in the scent profiles produced by different species. We have analyzed the genetic differences between A. majus and A. linkianum, two species divergent in the emission of methyl benzoate, methyl cinnamate, acetophenone, and ocimene. The genetic analysis showed that all compounds segregated in a Mendelian fashion attributable to one or two loci with simple or epistatic interactions. Several lines lacked methyl benzoate, a major Volatile Organic Compound emitted by A. majus but missing in A. linkianum. Using a candidate gene approach, we found that the BENZOIC ACID CARBOXYMETHYL TRANSFERASE from A. linkianum appeared to be a null allele as we could not detect mRNA expression. The coding region did not show significant differences that could explain the loss of expression. The intron-exon boundaries was also conserved indicating that there is no alternative splicing in A. linkianum as compared to A. majus. However, it showed multiple polymorphisms in the 5' promoter region including two insertions, one harboring an IDLE MITE transposon with additional sequences with high homology to the PLENA locus and a second one with somewhat lower homology to the regulatory region of the VENOSA locus. It also had a 778 bp deletion as compared to the A. majus BAMT promoter region. Our results show that the differences in scent emission between A. majus and A. linkianum may be traced back to single genes involved in discrete biosynthetic reactions such as benzoic acid methylation. Thus, natural variation of this complex trait maybe the result of combinations of wild type, and loss of function alleles in different genes involved in discrete VOCs biosynthesis. Furthermore, the presence of active transposable elements in the genus may account for rapid evolution and instability, raising the possibility of adaptation to local pollinators.

  18. Formic acid enhanced effective degradation of methyl orange dye in aqueous solutions under UV-Vis irradiation.

    PubMed

    Wang, Jingjing; Bai, Renbi

    2016-09-15

    Developing efficient technologies to treat recalcitrant organic dye wastewater has long been of great research and practical interest. In this study, a small molecule, formic acid (FA), was applied as a process enhancer for the degradation of methyl orange (MO) dye as a model recalcitrant organic pollutant in aqueous solutions under the condition of UV-Vis light irradiation and air aeration at the ambient temperature of 25 °C. It was found that the decolouration of the dye solutions can be rapidly achieved, reducing the time, for example, from around 17.6 h without FA to mostly about less than 2 h with the presence of FA. The mineralization rate of MO dye reached as high as 81.8% in 1.5 h in the case of initial MO dye concentration at 25 mg L(-1), which is in contrast to nearly no mineralization of the MO dye for a similar system without the FA added. The study revealed that the generation of the H2O2 species in the system was enhanced and the produced OH radicals effectively contributed to the degradation of the MO dye. Process parameters such as the initial concentration of MO dye, FA dosage and solution pH were all found to have some effect on the degradation efficiency under the same condition of UV-Vis light irradiation and air aeration. The MO dye degradation performance was found to follow a first-order reaction rate to the MO dye concentration in most cases and there existed a positive correlation between the reaction rate constant and the initial FA concentration. Compared to the traditional H2O2/UV-Vis oxidation system, the use of FA as a process-enhancing agent can have the advantages of low cost, easy availability, and safe to use. The study hence demonstrates a promising approach to use a readily available small molecule of FA to enhance the degradation of recalcitrant organic pollutants, such as MO dye, especially for their pre-treatment.

  19. Gibbs energy additivity approaches to QSRR in generating gas chromatographic retention time for identification of fatty acid methyl ester.

    PubMed

    Pojjanapornpun, Siriluck; Aryusuk, Kornkanok; Lilitchan, Supathra; Krisnangkura, Kanit

    2017-02-06

    The Gibbs energy additivity method was used to correlate the retention time (t R) of common fatty acid methyl esters (FAMEs) to their chemical structures. The t R of 20 standard FAMEs eluted from three capillary columns of different polarities (ZB-WAXplus, BPX70, and SLB-IL111) under both isothermal gas chromatography and temperature-programmed gas chromatography (TPGC) conditions were accurately predicted. Also, the predicted t R of FAMEs prepared from flowering pak choi seed oil obtained by multistep TPGC with the BPX70 column were within 1.0% of the experimental t R. The predicted t R or mathematical t R (t R(math)) values could possibly be used as references in identification of common FAMEs. Hence, FAMEs prepared from horse mussel and fish oil capsules were chromatographed on the BPX70 and ZB-WAXplus columns in single-step and multistep TPGC. Identification was done by comparison of t R with the t R of standard FAMEs and with t R(math). Both showed correct identifications. The proposed model has six numeric constants. Five of six could be directly transferred to other columns of the same stationary phase. The first numeric constant (a), which contained the column phase ratio, could also be transferred with the adjustment of the column phase ratio to the actual phase ratio of the transferred column. Additionally, the numeric constants could be transferred across laboratories, with similar correction of the first numeric constant. The TPGC t R predicted with the transferred column constants were in good agreement with the reported experimental t R of FAMEs. Moreover, hexane was used in place of the conventional t M marker in the calculation. Hence, the experimental methods were much simplified and practically feasible. The proposed method for using t R(math) as the references would provide an alternative to the uses of real FAMEs as the references. It is simple and rapid and with good accuracy compared with the use of experimental t R as references.

  20. Synthesis and preliminary biological evaluation of S-11C-methyl-D-cysteine as a new amino acid PET tracer for cancer imaging.

    PubMed

    Huang, Tingting; Tang, Ganghua; Wang, Hongliang; Nie, Dahong; Tang, Xiaolan; Liang, Xiang; Hu, Kongzhen; Yi, Chang; Yao, Baoguo; Tang, Caihua

    2015-04-01

    S-(11)C-methyl-L-cysteine (LMCYS) is an attractive amino acid tracer for clinical tumor positron emission tomography (PET) imaging. D-isomers of some radiolabeled amino acids are potential PET tracers for tumor imaging. In this work, S-(11)C-methyl-D-cysteine (DMCYS), a D-amino acid isomer of S-(11)C-methyl-cysteine for tumor imaging was developed and evaluated. DMCYS was prepared by (11)C-methylation of the precursor D-cysteine, with an uncorrected radiochemical yield over 50 % from (11)CH3I within a total synthesis time from (11)CO2 about 12 min. In vitro competitive inhibition studies showed that DMCYS uptake was primarily transported through the Na(+)-independent system L, and also the Na(+)-dependent system B(0,+) and system ASC, with almost no system A. In vitro incorporation experiments indicated that almost no protein incorporation was found in Hepa 1-6 hepatoma cell lines. Biodistribution studies demonstrated higher uptake of DMCYS in pancreas and liver at 5 min post-injection, relatively lower uptake in brain and muscle, and faster radioactivity clearance from most tissues than those of L-isomer during the entire observation time. In the PET imaging of S180 fibrosarcoma-bearing mice and turpentine-induced inflammatory model mice, 2-(18)F-fluoro-2-deoxy-D-glucose (FDG) exhibited significantly high accumulation in both tumor and inflammatory lesion with low tumor-to-inflammation ratio of 1.40, and LMCYS showed low tumor-to-inflammation ratio of 1.64 at 60 min post-injection. By contrast, DMCYS showed moderate accumulation in tumor and very low uptake in inflammatory lesion, leading to relatively higher tumor-to-inflammation ratio of 2.25 than (11)C-methyl-L-methionine (MET) (1.85) at 60 min post-injection. Also, PET images of orthotopic transplanted glioma models demonstrated that low uptake of DMCYS in normal brain tissue and high uptake in brain glioma tissue were observed. The results suggest that DMCYS is a little better than the corresponding L

  1. Optimization of a gas chromatography-mass spectrometry method with methyl chloroformate derivatization for quantification of amino acids in plant tissue.

    PubMed

    Vancompernolle, Bram; Croes, Kim; Angenon, Geert

    2016-04-01

    Rapid, easy and reliable quantification of amino acids is crucial in research on plant amino acid metabolism and nutritional improvement of crops via enrichment of essential amino acids. A recently reported analysis method, based on solid phase extraction (SPE), derivatization with methyl chloroformate and gas chromatography-mass spectrometry was optimized and tested on three-week-old Arabidopsis thaliana leaf tissues. Optimization of the SPE cleanup yielded recovery rates of minimum 95% for all amino acids (except arginine). Variations in accuracy and precision did not exceed 12.5%, except for cysteine, histidine and tryptophane, which were excluded from analysis. Quantification of overlapping peaks for isoleucine/threonine and proline/asparagine was possible by selection of two specific fragment ions for each amino acid. Of the 16 selected amino acids, 14 were quantified successfully in at least 75% of the samples, while methionine and tyrosine were only quantifiable in 6% and 42%, respectively. A case study on the aspartate super pathway confirmed the applicability of the optimized method on wild type and genetically modified plants: external supplementation of methionine or lysine yielded a 146-fold or 27-fold increase in the respective absolute amino acid levels compared with the control treatment. Induced expression of dhdps-r1 (a mutated lysine biosynthesis gene encoding a feedback insensitive enzyme) caused an 83-fold increase in absolute lysine levels.

  2. Possible modulation of N-methyl-D,L-aspartic acid induced prolactin release by testicular steroids in the adult male rhesus monkey

    SciTech Connect

    Arslan, M.; Rizvi, S.S.R.; Jahan, S.; Zaidi, P.; Shahab, M. )

    1991-01-01

    N-methyl-D,L-aspartic acid (NMA), an agonist of the neurotransmitter glutamate has been shown to acutely stimulate the release of prolactin (PRL) in intact rats and monkeys. To further investigate the role of neuroexcitatory amino acids in PRL secretion, the effects of NMA administration were examined on PRL release in long term orchidectomized adult rhesus monkeys, in both the absence and presence of testosterone. Intact and long term castrated adult male monkeys weighing between 8-13 kg, were implanted with a catheter via the saphenous vein for blood withdrawal and drug infusion. Blood samples were collected at 10 min intervals for 50 min before and 70 min after administration of the drug or vehicle. Plasma PRL concentrations were estimated using radioimmunoassay. Whereas a single iv injection of NMA induced a prompt discharge of PRL in intact monkeys, an identical dose had surprisingly no effect on PRL secretion in orchidectomized animals. On the other hand, plasma PRL increases in response to a challenge dose of thyrotropin releasing hormone were similar in magnitude in the two groups of monkeys. Testosterone replacement in orchidectomized animals by parenteral administration of testosterone enanthate reinitiated the PRL responsiveness to acute NMA stimulation. These results indicate that N-methyl-D-aspartic acid (NMDA) dependent drive to PRL release in the adult male rhesus monkey may be overtly influenced by the sex steroid milieu.

  3. Corrosion resistance of siloxane-poly(methyl methacrylate) hybrid films modified with acetic acid on tin plate substrates: Influence of tetraethoxysilane addition

    NASA Astrophysics Data System (ADS)

    Kunst, S. R.; Cardoso, H. R. P.; Oliveira, C. T.; Santana, J. A.; Sarmento, V. H. V.; Muller, I. L.; Malfatti, C. F.

    2014-04-01

    The aim of this paper is to study the corrosion resistance of hybrid films. Tin plate was coated with a siloxane-poly (methyl methacrylate) (PMMA) hybrid film prepared by sol-gel route with covalent bonds between the organic (PMMA) and inorganic (siloxane) phases obtained by hydrolysis and polycondensation of 3-(trimethoxysilylpropyl) methacrylate (TMSM) and polymerization of methyl methacrylate (MMA) using benzoyl peroxide (BPO) as a thermic initiator. Hydrolysis reactions were catalyzed by acetic acid solution avoiding the use of chlorine or stronger acids in the film preparation. The effect of the addition of tetraethoxysilane (TEOS) on the protective properties of the film was evaluated. The hydrophobicity of the film was determined by contact angle measurements, and the morphology was evaluated by scanning electron microscopy (SEM) and profilometry. The local nanostructure was investigated by Fourier transform infrared spectroscopy (FT-IR). The electrochemical behavior of the films was assessed by open circuit potential monitoring, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements in a 0.05 M NaCl solution. The mechanical behavior was evaluated by tribology. The results highlighted that the siloxane-PMMA hybrid films modified with acetic acid are promising anti-corrosive coatings that acts as an efficient diffusion barrier, protecting tin plates against corrosion. However, the coating properties were affected by the TEOS addition, which contributed for the thickness increase and irregular surface coverage.

  4. Benzyl and Methyl Fatty Hydroxamic Acids Based on Palm Kernel Oil as Chelating Agent for Liquid-Liquid Iron(III) Extraction

    PubMed Central

    Haron, Md Jelas; Jahangirian, Hossein; Silong, Sidik; Yusof, Nor Azah; Kassim, Anuar; Rafiee-Moghaddam, Roshanak; Mahdavi, Behnam; Peyda, Mazyar; Abdollahi, Yadollah; Amin, Jamileh

    2012-01-01

    Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively). The presence of a large amount of Mg(II), Ni(II), Al(III), Mn(II) and Co(II) ions did affect the iron(III) extraction. Finally stripping studies for recovering iron(III) from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane) were carried out at various concentrations of HCl, HNO3 and H2SO4. The results showed that the desired acid for recovery of iron(III) was 5 M HCl and quantitative recovery of iron(III) was achieved from Fe(III)-MFHs and Fe(III)-BFHs solutions in hexane containing 5 mg/L of Fe(III). PMID:22408444

  5. Integrating nitric oxide into salicylic acid and jasmonic acid/ ethylene plant defense pathways.

    PubMed

    Mur, Luis A J; Prats, Elena; Pierre, Sandra; Hall, Michael A; Hebelstrup, Kim H

    2013-01-01

    Plant defense against pests and pathogens is known to be conferred by either salicylic acid (SA) or jasmonic acid (JA)/ethylene (ET) pathways, depending on infection or herbivore-grazing strategy. It is well attested that SA and JA/ET pathways are mutually antagonistic allowing defense responses to be tailored to particular biotic stresses. Nitric oxide (NO) has emerged as a major signal influencing resistance mediated by both signaling pathways but no attempt has been made to integrate NO into established SA/JA/ET interactions. NO has been shown to act as an inducer or suppressor of signaling along each pathway. NO will initiate SA biosynthesis and nitrosylate key cysteines on TGA-class transcription factors to aid in the initiation of SA-dependent gene expression. Against this, S-nitrosylation of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) will promote the NPR1 oligomerization within the cytoplasm to reduce TGA activation. In JA biosynthesis, NO will initiate the expression of JA biosynthetic enzymes, presumably to over-come any antagonistic effects of SA on JA-mediated transcription. NO will also initiate the expression of ET biosynthetic genes but a suppressive role is also observed in the S-nitrosylation and inhibition of S-adenosylmethionine transferases which provides methyl groups for ET production. Based on these data a model for NO action is proposed but we have also highlighted the need to understand when and how inductive and suppressive steps are used.

  6. Integrating nitric oxide into salicylic acid and jasmonic acid/ ethylene plant defense pathways

    PubMed Central

    Mur, Luis A. J.; Prats, Elena; Pierre, Sandra; Hall, Michael A.; Hebelstrup, Kim H.

    2013-01-01

    Plant defense against pests and pathogens is known to be conferred by either salicylic acid (SA) or jasmonic acid (JA)/ethylene (ET) pathways, depending on infection or herbivore-grazing strategy. It is well attested that SA and JA/ET pathways are mutually antagonistic allowing defense responses to be tailored to particular biotic stresses. Nitric oxide (NO) has emerged as a major signal influencing resistance mediated by both signaling pathways but no attempt has been made to integrate NO into established SA/JA/ET interactions. NO has been shown to act as an inducer or suppressor of signaling along each pathway. NO will initiate SA biosynthesis and nitrosylate key cysteines on TGA-class transcription factors to aid in the initiation of SA-dependent gene expression. Against this, S-nitrosylation of NONEXPRESSOR OF PATHOGENESIS-RELATED PROTEINS1 (NPR1) will promote the NPR1 oligomerization within the cytoplasm to reduce TGA activation. In JA biosynthesis, NO will initiate the expression of JA biosynthetic enzymes, presumably to over-come any antagonistic effects of SA on JA-mediated transcription. NO will also initiate the expression of ET biosynthetic genes but a suppressive role is also observed in the S-nitrosylation and inhibition of S-adenosylmethionine transferases which provides methyl groups for ET production. Based on these data a model for NO action is proposed but we have also highlighted the need to understand when and how inductive and suppressive steps are used. PMID:23818890

  7. Investigation of 60Co γ-irradiated L-(-) malic acid, N-methyl- DL-valine and L-glutamic acid γ-ethyl ester by electron paramagnetic resonance technique

    NASA Astrophysics Data System (ADS)

    Başkan, M. Halim; Aydın, Murat; Osmanoğlu, Şemsettin

    The electron paramagnetic resonance spectra of γ-irradiated L-(-) malic acid, N-methyl- DL-valine and L-glutamic acid γ-ethyl ester powders have been investigation at room temperature. Radiation damage centres are attributed to HOOCCH 2ĊHCOOH, (CH 3) 2ĊCH(NHCH 3)COOH and C 2H 5OCOCH 2CH 2Ċ(NH 2)COOH radicals, respectively. The spectra have been computer simulated. The EPR parameters of the observed radicals have been determined and discussed.

  8. Acid-base and distribution equilibria of 5,7-dichloro-2-methyl-8-hydroxyquinoline in Brij-35 micellar media solutions.

    PubMed

    Beltrán, J L; Codony, R; Granados, M; Izquierdo, A; Prat, M D

    1993-02-01

    The acid-base equilibria of 5,7-dichloro-2-methyl-8-hydroxyquinoline (HQ) have been examined spectrophotometrically in aqueous micellar solution of the non-ionic surfactant Brij-35. The differences between apparent pK(a) values at different surfactant concentrations can be quantitatively explained in terms of the extraction constants of the neutral species HQ and the ion-pair Na(+)Q(-). Calculations have been performed by means of SPDIS program, developed in this work to handle multiwavelength spectrophotometric data in micellar systems.

  9. Role of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor regulation in stress-induced pain chronification

    PubMed Central

    Liu, Sufang; Tao, Feng

    2017-01-01

    Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery. PMID:28289513

  10. Modulation of DL-. alpha. -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/quisqualate receptors by phospholipase A sub 2 : A necessary step in long-term potentiation

    SciTech Connect

    Massicotte, G.; Baudry, M. ); Vanderklish, P.; Lynch, G. )

    1991-03-01

    The effects of kainate (KA)-induced epileptic seizures on the binding properites of hippocampal glutamate receptors, on the modulation of DL-{alpha}-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/quisqualate receptor by phospholipase A{sub 2} (PLA{sub 2}), and on the formation of long-term potentiation (LTP) were studied in hippocampal membranes and hippocampal slices. Systemic administration of KA produced specific changes in the binding properties of the AMPA/quisqualate receptors and its regulation. Whereas the binding of various ligands to the N-methyl-D-aspartate receptors was not modified by KA treatment, there was a singificant decrease in the maximal number of binding sites for ({sup 3}H)AMPA. The loss of LTP was not due to changes in postsynaptic responses elicited by the bursts that trigger the potentiation effect, thus suggesting that KA treatment disrupts processes that follow N-methyl-D-aspartate receptor activation. Systemic administration of KA was associated with calpain activation as the amount of spectrin breakdown products was increased severalfold in hippocampus but not in cerebellum. Pretreatment of telencephalic membranes with calpain greatly reduced the PLA{sub 2}-induced increase in ({sup 3}H)AMPA binding. The results provide evidence in favor of an essential role of PLA{sub 2} in the development of LTP and suggest that the order of activation of different calcium-dependent processes is critical for producing the final changes underlying LTP.

  11. Fast comprehensive two-dimensional gas chromatography method for fatty acid methyl ester separation and quantification using dual ionic liquid columns.

    PubMed

    Nosheen, Asia; Mitrevski, Blagoj; Bano, Asghari; Marriott, Philip J

    2013-10-18

    Safflower oil is a complex mixture of C18 saturated and unsaturated fatty acids amongst other fatty acids, and achieving separation between these similar structure components using one dimensional gas chromatography (GC) may be difficult. This investigation aims to obtain improved separation of fatty acid methyl esters in safflower oil, and their quantification using comprehensive two-dimensional GC (GC×GC). Here, GC×GC separation is accomplished by the coupling of two ionic liquid (IL) column phases: the combination of SLB-IL111 with IL59 column phases was finally selected since it provided excellent separation of a FAME standard mixture, as well as fatty acids in safflower and linseed oil, compared to other tested column sets. Safflower oil FAME were well separated in a short run of 16min. FAME validation was demonstrated by method reproducibility, linearity over a range up to 500mgL(-1), and limits of detection which ranged from 1.9mgL(-1) to 5.2mgL(-1) at a split ratio of 20:1. Quantification was carried out using two dilution levels of 200-fold for major components and 20-fold for trace components. The fatty acids C15:0 and C17:0 were not reported previously in safflower oil. The SLB-IL111/IL59 column set proved to be an effective and novel configuration for separation and quantification of vegetable and animal oil fatty acids.

  12. Production of Jatropha biodiesel fuel over sulfonic acid-based solid acids.

    PubMed

    Chen, Shih-Yuan; Lao-Ubol, Supranee; Mochizuki, Takehisa; Abe, Yohko; Toba, Makoto; Yoshimura, Yuji

    2014-04-01

    Sulfonic acid-functionalized platelet SBA-15 mesoporous silica with an acid capacity of 2.44mmol H(+) g-cat(-1) (shortly termed 15SA-SBA-15-p) was one-pot synthesized by co-condensation method. When applied as solid acid catalyst in synthesis of Jatropha biodiesel fuel (BDF), the 15SA-SBA-15-p catalyst showed higher activity and resistances to water and free fatty acid (FFA) than commercial sulfonic resins of Amberlyst-15 and SAC-13. For the continuous Jatropha BDF production, a steady 75-78wt% of fatty acid methyl ester (FAME) content was obtained over 15SA-SBA-15-p catalyst at 150°C for 75h, whereas the Amberlyst-15 and SAC-13 catalysts were quickly deactivated due to the decomposition of thermally unstable framework and serious leaching of sulfonic acids. More importantly, the quality, stability and cold flow characteristic of Jatropha BDF synthesized by 15SA-SBA-15-p catalyst were better than those synthesized by Amberlyst-15 and SAC-13 catalysts, making the blending with petro-diesel an easy task.

  13. Induction of benzoic acid 2-hydroxylase in virus-inoculated tobacco

    SciTech Connect

    Leon, J.; Yalpani, N.; Raskin, I.; Lawton, M.A. )

    1993-10-01

    Salicylic acid (SA) plays an important role in the induction of plant resistance to pathogens. An accompanying article shows that SA is synthesized via the decarboxylation of cinnamic acid to benzoic acid (BA), which is, in turn, hydroxylated to SA. Leaf extracts of tobacco catalyze the 2-hydroxylation of Ba to SA. The monooxygenase catalyzing this reaction, benzoic acid 2-hydroxylase (BA2H), required NAD(P)H or reduced methyl viologen as an electron donor. BA2H activity was detected in healthy tobacco leaf extracts (1-2 nmol h[sup [minus]1] g[sup [minus]1] fresh weight) and was significantly increased upon inoculation with tobacco mosaic virus (TMV). This increase paralleled the levels of free SA in the leaves. Induction of BA2H activity was restricted to tissue expressing a hypersensitive response at 24[degrees]C. TMV induction of BA2H activity and Sa accumulation were inhibited when inoculated tobacco plants were incubated for 4 d at 32[degrees]C and then transferred to 24[degrees]C, they showed a 15-fold increase in BA2H activity and a 65-fold increase in free SA content compared with healthy plants incubated at 24[degrees]C. Treatment of leaf tissue with the protein synthesis inhibitor cycloheximide blocked the induction of BA2H activity by TMV. The effect of TMV inoculation on BA2H could be duplicated by infiltrating leaf discs of healthy plants with BA. This response was observed even when applied levels of BA were much lower than the levels observed in vivo after virus inoculation. Feeding tobacco leaves with phenylalanine, cinnamic acid, or o-coumaric acid (putative precursors of SA) failed to trigger the induction of BA2H activity. BA2H appears to be a pathogen-inducible protein with an important regulatory role in SA accumulation during the development of induced resistance to TMV in tobacco. 33 refs., 6 figs., 3 tabs.

  14. Preparative separation of cis- and trans-isomers of unsaturated fatty acid methyl esters contained in edible oils by reversed-phase high-performance liquid chromatography.

    PubMed

    Tsuzuki, Wakako; Ushida, Kaori

    2009-04-01

    In order to measure exactly the trans-fatty acids content in food materials, a preparative group separation of cis- and trans-isomers of unsaturated fatty acid methyl esters (FAMEs) was achieved by an isocratic reversed-phase HPLC (RP-HPLC) method. The trans-isomers of 16:1, 18:1, 18:2, 18:3, 20:1 and 22:1 FAMEs were readily separated from the corresponding cis-isomers by a COSMOSIL Cholester C18 column (4.6 mm I.D. x 250 mm, Nacalai Tesque) or a TSKgel ODS-100Z column (4.6 mm I.D. x 250 mm, TOSOH), using acetonitrile as the mobile phase. This method was applied for determining the trans-18:1 fatty acid content in partially hydrogenated rapeseed oil. The methyl esters of cis- and trans-18:1 isomers of the oil were collected as two separate fractions by the developed RP-HPLC method. Each fraction was analyzed by gas chromatography (GC) for both qualitative and quantitative information on its positional isomers. By a combination of RP-HPLC and GC methods, a nearly complete separation of cis- and trans-18:1 positional isomers was achieved and the trans-18:1 fatty acid content was able to be evaluated more precisely than is possible by the direct GC method. The reproducibility of cis- and trans-18:1 isomers fractionated by the RP-HPLC method was better than 98%. These results suggested that the preparative RP-HPLC method developed in this study could be a powerful tool for trans-fatty acid analysis in edible oils and food products as an alternative to silver-ion chromatography.

  15. The Salicylic Acid-Mediated Release of Plant Volatiles Affects the Host Choice of Bemisia tabaci

    PubMed Central

    Shi, Xiaobin; Chen, Gong; Tian, Lixia; Peng, Zhengke; Xie, Wen; Wu, Qingjun; Wang, Shaoli; Zhou, Xuguo; Zhang, Youjun

    2016-01-01

    The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) causes serious crop losses worldwide by transmitting viruses. We have previously shown that salicylic acid (SA)-related plant defenses directly affect whiteflies. In this study, we applied exogenous SA to tomato plants in order to investigate the interaction between SA-induced plant volatiles and nonviruliferous B. tabaci B and Q or B- and Q-carrying tomato yellow leaf curl virus (TYLCV). The results showed that exogenous SA caused plants to repel nonviruliferous whiteflies, but the effect was reduced when the SA concentration was low and when the whiteflies were viruliferous. Exogenous SA increased the number and quantity of plant volatiles—especially the quantity of methyl salicylate and δ-limonene. In Y-tube olfactometer assays, methyl salicylate and δ-limonene repelled the whiteflies, but the repellency was reduced for viruliferous Q. We suggest that the release of plant volatiles as mediated by SA affects the interaction between whiteflies, plants, and viruses. Further studies are needed to determine why viruliferous Q is less sensitive than nonviruliferous Q to repellent plant volatiles. PMID:27376280

  16. Effects of 2-(3-methyl-cinnamyl-hydrazono)-propionate on fatty acid and glucose oxidation in the isolated rat diaphragm using 14C-labelled substrates. Hydrazonopropionic acids, a new class of hypoglycaemic substances, VIII.

    PubMed

    Binder, L; Oellerich, M; Haeckel, R; Beneking, M

    1988-12-01

    The influence of 2-(3-methyl-cinnamyl-hydrazono)-propionate on the utilization of various substrates in isolated rat hemidiaphragms was investigated in comparison with other hypoglycaemic compounds. The effect of 2-(3-methyl-cinnamyl-hydrazono)-propionate was concentration-dependent. At a concentration of 0.5 mmol/l 2-(3-methyl-cinnamyl-hydrazono)-propionate, glucose utilization increased from 0.276 +/- 0.043 mumol.g-1.l-1 to 0.894 +/- 0.303 mumol.g-1.l-1 (p less than 0.05). Pyruvate and lactate utilization were stimulated to a lesser extent, while acetate utilization remained nearly constant. At a concentration of 2 mmol/l 2-(3-methyl-cinnamyl-hydrazono)-propionate, the oxidation of palmitate decreased from 0.214 +/- 0.017 mumol.g-1.l-1 to 0.060 +/- 0.005 mumol.g-1.l-1, while the oxidation of octanoate was not decreased. These findings point to a stimulation of the glycolytic flux by inhibition of long-chain fatty acid oxidation.

  17. Methylation matters

    PubMed Central

    Costello, J.; Plass, C.

    2001-01-01

    DNA methylation is not just for basic scientists any more. There is a growing awareness in the medical field that having the correct pattern of genomic methylation is essential for healthy cells and organs. If methylation patterns are not properly established or maintained, disorders as diverse as mental retardation, immune deficiency, and sporadic or inherited cancers may follow. Through inappropriate silencing of growth regulating genes and simultaneous destabilisation of whole chromosomes, methylation defects help create a chaotic state from which cancer cells evolve. Methylation defects are present in cells before the onset of obvious malignancy and therefore cannot be explained simply as a consequence of a deregulated cancer cell. Researchers are now able to detect with exquisite sensitivity the cells harbouring methylation defects, sometimes months or years before the time when cancer is clinically detectable. Furthermore, aberrant methylation of specific genes has been directly linked with the tumour response to chemotherapy and patient survival. Advances in our ability to observe the methylation status of the entire cancer cell genome have led us to the unmistakable conclusion that methylation abnormalities are far more prevalent than expected. This methylomics approach permits the integration of an ever growing repertoire of methylation defects with the genetic alterations catalogued from tumours over the past two decades. Here we discuss the current knowledge of DNA methylation in normal cells and disease states, and how this relates directly to our current understanding of the mechanisms by which tumours arise.


Keywords: methylation; cancer PMID:11333864

  18. The Effect of the Methylation and N-H Acidic Group on the Physicochemical Properties of Imidazolium-Based Ionic Liquids

    PubMed Central

    Rodrigues, Ana S.M.C.; Rocha, Marisa A. A.; Almeida, Hugo F. D.; Neves, Catarina M. S. S.; Lopes-da-Silva, José A.; Freire, Mara G.; Coutinho, João A. P.; Santos, Luís M. N. B. F.

    2017-01-01

    This work presents and highlights the differentiation of the physicochemical properties of the [C1Him][NTf2], [C2Him][NTf2], [1C12C1Him][NTf2], and [1C42C13C1im][NTf2] that are related with the strong bulk interaction potential, which highlights the differentiation on the physicochemical arising from the presence of the acidic group (N-H) as well as the methylation in position 2 (C(2)) of the imidazolium ring. Densities, viscosities, refractive indices and surface tensions in a wide range of temperatures, as well as, isobaric heat capacities at 298.15 K, for this IL series are presented and discussed. It was found that the volumetric properties are barely affected by the geometric and structural isomerization, following a quite regular trend. A linear correlation between the glass transition temperature, Tg, and the alkyl chain size was found; however, ILs with the acidic N-H group present a significant higher Tg than the [1CN-13C1im][NTf2] and [1CN3CNim][NTf2] series. It was found that the most viscous ILs, ([1C1Him][NTf2], [1C2Him][NTf2] and [1C12C1Him][NTf2]) have an acidic N-H group in the imidazolium ring in agreement with the observed increase of energy barrier of flow. The methylation in position 2, C(2), as well as, the N-H acidic group in the imidazolium ring, contribute to a significant variation in the cation-anion interactions and their dynamics, which is reflected in their charge distribution and polarizability leading to a significant differentiation of the refractive indices, surface tension and heat capacities. The observed differentiation of the physicochemical properties of the [1C1Him][NTf2], [1C2Him][NTf2], [1C12C1Him][NTf2], and [1C42C13C1im][NTf2] are an indication of the stronger bulk interaction potential, which highlights the effect that arises from the presence of the acidic group (N-H) as well as the methylation in position 2 of the imidazolium ring. PMID:26082427

  19. Synthesis of C-11-{beta}-aminoisobutyric acid (C-11-{beta}-AlB): A major in vivo catabolite of [methyl-C-11]thymidine

    SciTech Connect

    Alauddin, M.M.; Conti, P.S.; Fissekis, J.D.

    1995-05-01

    Carbon-11 labeled thymidine (TdR) is being used for brain tumor imaging in patients with PET. Following clearance of 5-methyl C-11 TdR from plasma in humans, there is a progressive increase of C-11 activity in normal brain and tumor presumably secondary to accumulation of C-11 beta-AIB, a major by-product of thymidine catabolism in vivo. Canine studies have demonstrated that the major radiolabeled species in acid soluble extracts of brain and tumor tissues during C-14 TdR studies is beta-AIB. The previously reported synthesis of beta-AIB is not suitable for incorporation of carbon-11. A convenient method of synthesis of C-11 beta-AIB was developed where commercially available beta-alanine ethyl ester was converted to the cold precursor reagent, benzaldimine-beta-alanine ethyl ester, in 87% yield. Treatment of the imine derivative with LDA (1.1 eq) in THF at -78{degrees} C, followed by addition of iodomethane (1.1 eq) produced the alpha-methylated benzaldimine-beta-alanine ethyl ester in 73% chemical yield. Deprotection of the amino group by acidic hydrolysis followed by basic hydrolysis of the ester group produced the desired product in 50% chemical yield. Chemical structures of unlabeled intermediates and product were confirmed by H-1 NMR and CI mass spectrometry. Labeling was accomplished using C-11-methyl iodide prepared from C-11-CO{sub 2} according to literature methods. After removal of protecting groups and neutralization, the enatiomeric mixture was purified by HPLC using a semipreparative reverse phase C-18 column and PBS as eluent. The desired compound was eluted at 8.26 minutes. In preliminary runs, the synthesis time was 39 minutes including HPLC purification, with radiochemical yields of 5-6% (EOB). Radiochemical purity was >99%

  20. Noncatalytic transformation of the crude lipid of ChlorellaI vulgaris into fatty acid methyl ester (FAME) with charcoal via a thermo-chemical process.

    PubMed

    Kwon, Eilhann E; Jeon, Young Jae; Yi, Haakrho

    2013-02-01

    The noncatalytic transformation of the crude lipid of Chlorella vulgaris (C. vulgaris) into fatty acid methyl ester (FAME) via a thermo-chemical process was mainly investigated in this work. The crude lipid of C. vulgaris was recovered by means of solvent extraction from C. vulgaris cultivated in a raceway pond. The conventional catalyzed transesterification of crude lipid of C. vulgaris is notably inhibited by the impurities contained in the crude lipid of C. vulgaris. These impurities are inevitably derived from the solvent extraction process for C. vulgaris. However, this work presents the noncatalytic transesterification of microalgal lipid into FAME, which could be an alternative option. For example, the noncatalytic transformation of microalgal lipid into FAME provides evidence that the esterification of free fatty acids (FFAs) and the transesterification of triglycerides can be combined into a single step less susceptible to the impurities and with a high conversion efficiency (∼97%).