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Sample records for bearing long-chain alkyl

  1. Thermodynamic Interactions between Polystyrene and Long-Chain Poly(n-Alkyl Acrylates) Derived from Plant Oils.

    Science.gov (United States)

    Wang, Shu; Robertson, Megan L

    2015-06-10

    Vegetable oils and their fatty acids are promising sources for the derivation of polymers. Long-chain poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) are readily derived from fatty acids through conversion of the carboxylic acid end-group to an acrylate or methacrylate group. The resulting polymers contain long alkyl side-chains with around 10-22 carbon atoms. Regardless of the monomer source, the presence of alkyl side-chains in poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) provides a convenient mechanism for tuning their physical properties. The development of structured multicomponent materials, including block copolymers and blends, containing poly(n-alkyl acrylates) and poly(n-alkyl methacrylates) requires knowledge of the thermodynamic interactions governing their self-assembly, typically described by the Flory-Huggins interaction parameter χ. We have investigated the χ parameter between polystyrene and long-chain poly(n-alkyl acrylate) homopolymers and copolymers: specifically we have included poly(stearyl acrylate), poly(lauryl acrylate), and their random copolymers. Lauryl and stearyl acrylate were chosen as model alkyl acrylates derived from vegetable oils and have alkyl side-chain lengths of 12 and 18 carbon atoms, respectively. Polystyrene is included in this study as a model petroleum-sourced polymer, which has wide applicability in commercially relevant multicomponent polymeric materials. Two independent methods were employed to measure the χ parameter: cloud point measurements on binary blends and characterization of the order-disorder transition of triblock copolymers, which were in relatively good agreement with one another. The χ parameter was found to be independent of the alkyl side-chain length (n) for large values of n (i.e., n > 10). This behavior is in stark contrast to the n-dependence of the χ parameter predicted from solubility parameter theory. Our study complements prior work investigating the interactions between

  2. Benzene alkylation with long chain olefins catalyzed by ionic liquids: a review

    Institute of Scientific and Technical Information of China (English)

    Congzhen QIAO; Yonghong CAI; Quanhui GUO

    2008-01-01

    The introduction of ionic liquids to alkylation process gives a choice for "green production" in the pet-rochemical and detergent industry.A lot of papers and patents have been published using chloroaluminate ionic liquid as a novel catalyst for alkylation with high reactivity and easy separation from reactants.These included the acid-ity,characterization,determination and catalysis technolo-gies in batch and continuous operation mode for different scales.According to published data and several results of pilot alkylation,including the authors' experience,the pro-spect of chloroaluminate ionic liquids for commercials was also discussed.It has been pointed out that there still are many difficulties and challenges to be overcome for com-mercial application of the ionic liquid catalyst.

  3. Reactions of 1,4-bis(tetrazole)benzenes: formation of long chain alkyl halides

    OpenAIRE

    Kelleher, Fintan; Bond, Andrew; Fleming, Adrienne; McGinley, John; Prajapati, Vipa

    2006-01-01

    The reactions of 1,4-bis[2-(tributylstannyl)tetrazol-5-yl]benzene with α,ω-dibromoalkanes were carried out in order to synthesise pendant alkyl halide derivatives of the parent bis-tetrazole. This led to the formation of several alkyl halide derivatives, substituted variously at N1 or N2 on the tetrazole ring. The crystal structures of 1,4-bis[(2-(4-bromobutyl)tetrazol-5-yl)]benzene (2-N,2-N′), 1,4-bis[(2-(4-bromobutyl)tetrazol-5-yl)]benzene (1-N,2-N′) and 1,4-bis[(2-(8-bromooctyl)tetra...

  4. Dendronized polyimides bearing long-chain alkyl groups and their application for vertically aligned nematic liquid crystal displays.

    Science.gov (United States)

    Tsuda, Yusuke; Min, Jae; Kuwahara, Renpei

    2009-11-01

    Polyimides having dendritic side chains were investigated. The terphenylene diamine monomer having a first-generation monodendron, 3,4,5-tris(n-dodecyloxy)-benzoate and the monomer having a second-generation monodendron, 3,4,5-tris[-3',4',5'-tri(n-dodecyloxy)benzyloxy]benzoate were successfully synthesized and the corresponding soluble dendritic polyimides were obtained by polycondensation with conventional tetracarboxylic dianhydride monomers such as benzophenone tertracarboxylic dianhydride (BTDA). The two-step polymerizations in NMP that is a general method for the synthesis of soluble polyimides is difficult; however, the expected dendritic polyimides can be obtained in aromatic polar solvents such as m-cresol and pyridine. The solubility of these dendoronized polyimides is characteristic; soluble in common organic solvents such as dichloromethane, chloroform, toluene and THF. These dendronized polyimides exhibited high glass transition temperatures and good thermal stability in both air and under nitrogen. Their application as alignment layers for LCDs was investigated, and it was found that these polyimides having dendritic side chains were applicable for the vertically aligned nematic liquid crystal displays (VAN-LCDs). PMID:20087476

  5. Dendronized Polyimides Bearing Long-Chain Alkyl Groups and Their Application for Vertically Aligned Nematic Liquid Crystal Displays

    Directory of Open Access Journals (Sweden)

    Yusuke Tsuda

    2009-11-01

    Full Text Available Polyimides having dendritic side chains were investigated. The terphenylene diamine monomer having a first-generation monodendron, 3,4,5-tris(n-dodecyloxy-benzoate and the monomer having a second-generation monodendron, 3,4,5-tris[-3’,4’,5’-tri(n-dodecyloxybenzyloxy]benzoate were successfully synthesized and the corresponding soluble dendritic polyimides were obtained by polycondensation with conventional tetracarboxylic dianhydride monomers such as benzophenone tertracarboxylic dianhydride (BTDA. The two-step polymerizations in NMP that is a general method for the synthesis of soluble polyimides is difficult; however, the expected dendritic polyimides can be obtained in aromatic polar solvents such as m-cresol and pyridine. The solubility of these dendoronized polyimides is characteristic; soluble in common organic solvents such as dichloromethane, chloroform, toluene and THF. These dendronized polyimides exhibited high glass transition temperatures and good thermal stability in both air and under nitrogen. Their application as alignment layers for LCDs was investigated, and it was found that these polyimides having dendritic side chains were applicable for the vertically aligned nematic liquid crystal displays (VAN-LCDs.

  6. Copper(I)-catalyzed carbon-halogen bond-selective boryl substitution of alkyl halides bearing terminal alkene moieties

    OpenAIRE

    Iwamoto, Hiroaki; Kubota, Koji; Yamamoto, Eiji; Ito, Hajime

    2015-01-01

    The selective boryl substitution of alkyl halides bearing terminal C=C double bonds has been achieved using a copper(I)/tricyclohexylphosphine or copper(I)/o-diphenylphosphinophenol catalyst. This reaction represents a useful complementary approach to conventional procedures for the hydroboration of C=C double bonds or the borylative cyclization of alkyl halides bearing terminal alkenes.

  7. Solid-phase extraction-gas chromatography and solid-phase extraction-gas chromatography-mass spectrometry determination of corrosion inhibiting long-chain primary alkyl amines in chemical treatment of boiler water in water-steam systems of power plants.

    Science.gov (United States)

    Kusch, Peter; Knupp, Gerd; Hergarten, Marcus; Kozupa, Marian; Majchrzak, Maria

    2006-04-28

    Gas chromatography with simultaneous flame-ionization detection (FID) and a nitrogen-phosphorus detection (NPD) as well as gas chromatography-mass spectrometry (GC/MS) has been used to characterize long-chain primary alkyl amines after derivatization with trifluoroacetic anhydride (TFAA). Electron impact ionization- (EI) and negative chemical ionization (NCI) mass spectra of trifluoroacetylated derivatives of the identified tert-octadecylamines are presented for the first time. The corrosion inhibiting alkyl amines were applied in a water-steam circuit of energy systems in the power industry. Solid-phase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated tert-octadecylamines in boiler water, superheated steam and condensate samples from the power plant. The estimated values were: 89 microg l(-1)(n = 5, RSD = 7.8%), 45 microg l(-1) (n = 5, RSD = 5.4%) and 37 microg l(-1)(n = 5, RSD = 2.3%), respectively. PMID:16483586

  8. Synthesis and Properties of Dendritic Long-Chain Esters as Crude Oil Flow Improver Additives

    Institute of Scientific and Technical Information of China (English)

    Li Cuiqin; Sun Peng; Shi Weiguang; Wang Jun

    2016-01-01

    The efifciencies of 6 kinds of macromolecules with dendritic structure in improving the lfow properties of crude oil were investigated. The dendritic additives were synthesized using low-generation dendritic poly(amidoamine) and alkyl long-chain acrylic esters as starting materials, and their structures were characterized by the Fourier transform infrared spectroscopy, 1H-nuclear magnetic resonance and elemental analysis. The effects on the pour point and rheological properties of crude oil samples were studied. Efifciencies of dendritic long-chain esters were not only inlfuenced by the alky chain length, but also by the generation of dendrimer. The longer the alkyl chain of dendritic long-chain ester was, the better the effect in the reduction of pour point and apparent viscosity was. Efifciencies of 1.5 generation dendritic long-chain ester with 8 branched chains for the reduction of pour point and apparent viscosity were superior to those of 0.5 generation dendritic long-chain ester with 4 branched chains. Under the same conditions, efifciencies of 1.5 generation dendritic eighteen ester were superior to those of other 1.5 generation dendritic long-chain esters for the reduction of pour point and viscosity of crude oil.

  9. Synthesis of Single-stranded Polynorbornene with Pendant Group Bearing Benzenedicarboxaldehyde and Long Alkyl Chain

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ze; WU Hao-hao; WANG Chun-shan; FAN Kun-zeng

    2012-01-01

    An unprecedented single-stranded polynorbornene with the pendant group containing benzenedicarboxaldehyde and a long alkyl chain(12) was synthesized by ring-open metathesis polymerization(ROMP) of the corresponding monomer(11),which was obtained via the esterification of two crucial intermediates,namely,2-hexadecyloxy-5-hydroxymethy1-1,3-benzenedicarboxaldehyde(7,obtained via 6 steps) and 4-(4-aza-tricyclo[5.2.1.02.6]-dec-8en-4-yl)benzoic acid(10).The target compound and all the intermediates were characterized by infrared(IR),1H NMR and high resolution mass spectroscopy(HRMS) analysis.

  10. Efficient cross-coupling of aryl Grignard reagents with alkyl halides by recyclable ionic iron(III) complexes bearing a bis(phenol)-functionalized benzimidazolium cation.

    Science.gov (United States)

    Xia, Chong-Liang; Xie, Cun-Fei; Wu, Yu-Feng; Sun, Hong-Mei; Shen, Qi; Zhang, Yong

    2013-12-14

    A novel bis(phenol)-functionalized benzimidazolium salt, 1,3-bis(3,5-di-tert-butyl-2-hydroxybenzyl)benzimidazolium chloride (H3LCl, 1), was designed and used to prepare ionic iron(III) complexes of the type [H3L][FeX4] (X = Cl, 2; X = Br, 3). Both 2 and 3 were characterized by elemental analysis, Raman spectroscopy, electrospray ionization mass spectrometry and X-ray crystallography. The catalytic performances of 2 and 3 in cross-coupling reactions using aryl Grignard reagents with primary and secondary alkyl halides bearing β-hydrogens were studied. This analysis shows that complex 2 has good potential for alkyl chloride-mediated coupling. In comparison, complex 3 showed slightly lower catalytic activity. After decanting the product contained in the ethereal layer, complex 2 could be recycled at least eight times without significant loss of catalytic activity. PMID:24145602

  11. Mean field theory for long chain molecules

    Science.gov (United States)

    Pereira, Gerald G.

    1996-06-01

    We provide a mathematical formalism for a self-consistent mean field treatment of long chain molecules. The formalism is applied to the case of a neutral polymer under the excluded volume interaction. Upon scaling the problem in the N→∞ limit we find the natural scaling length RN, of the polymer, which is made up of (N+1) monomers or beads, is RN˜N3/5, the well known Flory result. The asymptotics of the problem is dominated by the neighborhood of the turning point, so that a uniformly valid Green's function solution of the differential equations is necessary. In the neighborhood of a point y* the scaled polymer density fN(x), is found to decay sharply. If we let x denote the scaled distance from one end of the chain to a point in space we obtain, for y*-x≳O(N-2/15), a closed form expression for the polymer density viz., fN(x)˜{1/2x2[fN(x)-fN(y*)]1/2} while for x-y*≳O(N-2/15) the density is shown to be, to leading order, zero. Although our results imply the rate of decay of the density at y* is O(N1/5) we are unable to verify this explicitly by calculating fN'(y*). We believe this is due to the inability of the WKB theory to correctly approximate solutions in regions of rapid variation. We suggest remedies for this, so that a complete self-consistent solution may be obtained.

  12. Bear

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The famous physicist made for his scholars this riddle. A fellow encountered a bear in a wasteland. There was nobody else there. Both were frightened and ran away. Fellow to the north, bear to the west. Suddenly the fellow stopped, aimed his gun to the south and shot the bear. What colour was the bear?

  13. Lubricated Bearing Lifetimes of a Multiply Alkylated Cyclopentane and a Linear Perfluoropolyether Fluid in Oscillatory Motion at Elevated Temperatures in Ultrahigh Vacuum

    Science.gov (United States)

    Braza, Joseph; Jansen, Mark J.; Jones, William R.

    2009-01-01

    Bearing life tests in vacuum with three space liquid lubricants, two multiply alkylated cyclopentanes (MACs) and a linear perfluoropolyether (PFPE) were performed. Test conditions included: an 89 N axial load (mean Hertzian stress 0.66 GPa), vacuum level below 7x10(exp -4) Pa, and a +/-30deg dither angle. Dither rate was 75 cycles per minute. Higher (110 to 122 C) and lower temperature tests (75 C) were performed. For the higher temperature tests, the PFPE, Fomblin (Ausimont SpA) Z25 outperformed Pennzane (Shell Global Solutions) X-2000 by more than an order of magnitude. Lubricant evaporation played a key role in these high temperature results. At 75 C, the order was reversed with both Pennzane X-1000 and X-2000 outperforming Fomblin Z25 by more than an order of magnitude. Most Pennzane tests were suspended without failure. The primary failure mechanism in these lower temperature tests was lubricant consumption in the tribocontacts.

  14. The slow dissociation rate of K-1602 contributes to the enhanced inhibitory activity of this novel alkyl-aryl-bearing fluoroketolide.

    Science.gov (United States)

    Krokidis, Marios; Bougas, Anthony; Stavropoulou, Maria; Kalpaxis, Dimitrios; Dinos, George P

    2016-04-01

    Ketolides belong to the latest generation of macrolides and are not only effective against macrolide susceptible bacterial strains but also against some macrolide resistant strains. Here we present data providing insights into the mechanism of action of K-1602, a novel alkyl-aryl-bearing fluoroketolide. According to our data, the K-1602 interacts with the ribosome as a one-step slow binding inhibitor, displaying an association rate constant equal to 0.28 × 10(4 )M(-1) s(-1) and a dissociation rate constant equal to 0.0025 min(-1). Both constants contribute to produce an overall inhibition constant Ki equal to 1.49 × 10(-8 )M, which correlates very well with the superior activity of this compound when compared with many other ketolides or fluoroketolides. PMID:25807301

  15. Palladium-catalyzed asymmetric alkylation in the synthesis of cyclopentanoid and cycloheptanoid core structures bearing all-carbon quaternary stereocenters

    KAUST Repository

    Hong, Allen Y.

    2011-12-01

    General catalytic asymmetric routes toward cyclopentanoid and cycloheptanoid core structures embedded in numerous natural products have been developed. The central stereoselective transformation in our divergent strategies is the enantioselective decarboxylative alkylation of seven-membered β-ketoesters to form α-quaternary vinylogous esters. Recognition of the unusual reactivity of β-hydroxyketones resulting from the addition of hydride or organometallic reagents enabled divergent access to γ-quaternary acylcyclopentenes through a ring contraction pathway or γ-quaternary cycloheptenones through a carbonyl transposition pathway. Synthetic applications of these compounds were explored through the preparation of mono-, bi-, and tricyclic derivatives that can serve as valuable intermediates for the total synthesis of complex natural products. This work complements our previous work with cyclohexanoid systems.

  16. Aggregation Behavior of Long-Chain Piperidinium Ionic Liquids in Ethylammonium Nitrate

    Directory of Open Access Journals (Sweden)

    Caili Dai

    2014-12-01

    Full Text Available Micelles formed by the long-chain piperidinium ionic liquids (ILs N-alkyl-N-methylpiperidinium bromide of general formula CnPDB (n = 12, 14, 16 in ethylammonium nitrate (EAN were investigated through surface tension and dissipative particle dynamics (DPD simulations. Through surface tension measurements, the critical micelle concentration (cmc, the effectiveness of surface tension reduction (Πcmc, the maximum excess surface concentration (Гmax and the minimum area occupied per surfactant molecule (Amin can be obtained. A series of thermodynamic parameters (DG0 m, DH0 m and DS0 m of micellization can be calculated and the results showed that the micellization was entropy-driven. In addition, the DPD simulation was performed to simulate the whole aggregation process behavior to better reveal the micelle formation process.

  17. Assessment of the environmental risk of long chain alcohols (LCOH)

    DEFF Research Database (Denmark)

    Belanger, Scott; Sanderson, Hans; Fisk, Peter;

    2009-01-01

    An environmental assessment of long-chain alcohols (LCOH) has recently been conducted under the OECD SIDS High Production Volume (HPV) Program via the Global International Council of Chemical Associations (ICCA) Aliphatic Alcohols Consortium. LCOH are used primarily as intermediates, as a precurs...

  18. Rapid Capacity Growth of Long Chain Fatty Alcohols

    Institute of Scientific and Technical Information of China (English)

    Shi Yuying

    2007-01-01

    @@ Long chain fatty alcohols here are referring to those alcohols with more than six carbon atoms per molecular.They are basic chemical raw materials for the synthesis of surfactants,detergents, plasticizers and various other fine chemicals and are extensively used in textile, household chemicals, papermaking, foodstuffs,pharmaceuticals and leather manufacturing sectors.

  19. On the contraction factors of long-chain branched macromolecules

    Czech Academy of Sciences Publication Activity Database

    Kratochvíl, Pavel; Netopilík, Miloš

    2014-01-01

    Roč. 51, February (2014), s. 177-181. ISSN 0014-3057 R&D Projects: GA ČR GCP205/11/J043 Institutional support: RVO:61389013 Keywords : long-chain branching * contraction factor * radius of gyration Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.005, year: 2014

  20. Helsingør Statement on poly- and perfluorinated alkyl substances (PFASs)

    DEFF Research Database (Denmark)

    Scheringer, Martin; Trier, Xenia; Cousins, Ian T.; de Voogt, Pim; Fletcher, Tony; Wang, Zhanyun; Webster, Thomas F.

    2014-01-01

    In this discussion paper, the transition from long-chain poly- and perfluorinated alkyl substances (PFASs) to fluorinated alternatives is addressed. Long-chain PFASs include perfluoroalkyl carboxylic acids (PFCAs) with 7 or more perfluorinated carbons, perfluoroalkyl sulfonic acids (PFSAs) with 6...

  1. Synthesis, characterization and antibacterial properties of dihydroxy quaternary ammonium salts with long chain alkyl bromides.

    Science.gov (United States)

    Liu, Wen-Shuai; Wang, Chun-Hua; Sun, Ju-Feng; Hou, Gui-Ge; Wang, Yu-Peng; Qu, Rong-Jun

    2015-01-01

    Five N-methyl-N-R-N,N-bis(2-hydroxyethyl) ammonium bromides (R = -benzyl (chloride, BNQAS), -dodecyl (C12QAS), -tetradecyl (C14QAS), -hexadecyl (C16QAS), -octadecyl (C18QAS)) were prepared based on N-methyldiethanolamine (MDEA) and halohydrocarbon. Five QAS were characterized by FTIR, NMR, and MS. BNQAS, C12QAS, C14QAS, and C16QAS were confirmed by X-ray single-crystal diffraction. Their antibacterial properties indicated good antibacterial abilities against E. coli, S. aureus, B. subtilis, especially C12QAS with the best antibacterial ability (100% to E. coli, 95.65% to S. aureus, and 91.41% to B. subtilis). In addition, C12QAS also displayed the best antifungal activities than BNQAS and C18QAS against Cytospora mandshurica, Botryosphaeria ribis, Physalospora piricola, and Glomerella cingulata with the ratio of full marks. The strategy provides a facile way to design and develop new types of antibacterial drugs for application in preventing the fruit rot, especially apple. PMID:25215430

  2. Sphingoid long chain bases prevent lung infection by Pseudomonas aeruginosa

    Science.gov (United States)

    Pewzner-Jung, Yael; Tavakoli Tabazavareh, Shaghayegh; Grassmé, Heike; Becker, Katrin Anne; Japtok, Lukasz; Steinmann, Jörg; Joseph, Tammar; Lang, Stephan; Tuemmler, Burkhard; Schuchman, Edward H; Lentsch, Alex B; Kleuser, Burkhard; Edwards, Michael J; Futerman, Anthony H; Gulbins, Erich

    2014-01-01

    Cystic fibrosis patients and patients with chronic obstructive pulmonary disease, trauma, burn wound, or patients requiring ventilation are susceptible to severe pulmonary infection by Pseudomonas aeruginosa. Physiological innate defense mechanisms against this pathogen, and their alterations in lung diseases, are for the most part unknown. We now demonstrate a role for the sphingoid long chain base, sphingosine, in determining susceptibility to lung infection by P. aeruginosa. Tracheal and bronchial sphingosine levels were significantly reduced in tissues from cystic fibrosis patients and from cystic fibrosis mouse models due to reduced activity of acid ceramidase, which generates sphingosine from ceramide. Inhalation of mice with sphingosine, with a sphingosine analog, FTY720, or with acid ceramidase rescued susceptible mice from infection. Our data suggest that luminal sphingosine in tracheal and bronchial epithelial cells prevents pulmonary P. aeruginosa infection in normal individuals, paving the way for novel therapeutic paradigms based on inhalation of acid ceramidase or of sphingoid long chain bases in lung infection. PMID:25085879

  3. Synthesis of Some New Long-chain Salen Catalysts

    Institute of Scientific and Technical Information of China (English)

    WU JinCai; TANG Ning; SUN Yang; ZHANG Ling; Song Bo; TAN MinYu

    2001-01-01

    @@ In the research of enantioselective epoxidation of unfunctionalized alkenes using Salen compounds, Katasuki1 and Jacobsen2 pointed out that 3 and 3′ groups of Salen were very important to increase the e.e of the catalytic product. Recently, in order to explore useful information concerning molecular design of metal catalysts for enantioselective epoxidation of trans-disubstituted alkenes, which remains an unresolved problem in the field of metal-catalyzed asymmetric epoxidation of unfunctionalized alkenes,some new Salen compounds containing long-chain in 3 and 3′ were designed and synthesized. We think these 3 and 3′ long-chain groups not only do as bulky group, but also act as second introduced chiral source. The following is the route:

  4. Effect of Long-Chain Fatty Acids on Anaerobic Digestion

    OpenAIRE

    Qian, Cheng

    2013-01-01

    An investigation was carried out to study whether long-chain fatty acids (LCFAs) have an effect on digestion of waste sludge under anaerobic conditions. Four different kinds of LCFAs were used in this study. The 18 carbon series with 0, 1, 2 and 3 double bonds were studied to evaluate the degree of saturation on fatty acid degradation. Due to their molecular structure, unsaturated LCFAs are more soluble than saturated LCFAs. Oleic, linoleic, linolenic acid with an ascending number of double b...

  5. Magnetization reversal in long chains of submicrometric Co dots

    OpenAIRE

    Martín, J.I.; Nogués i Sanmiquel, Josep; Schuller, Ivan K.; van Bael, M.J.; Temst, K; Van Haesendonck, C.; Moshchalkov, V. V.; Bruynseraede, Y.

    1998-01-01

    This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. Long chains of 400 nm diam Co dots prepared by combined electron-beam lithography exhibit interesting magnetotransport properties. The magnetoresistance of the chains of dots is markedly different from single Co films, indicating a strongly modified magnetization reversal process. Magnetic force microscopy(MFM) shows that, after magnetic saturat...

  6. Environment-friendly synthesis of long chain semiaromatic polyamides

    Directory of Open Access Journals (Sweden)

    2009-08-01

    Full Text Available Long chain semiaromatic polyamides were synthesized by the reactions of p-phenylenediacetic acid with long chain aliphatic diamines, and characterized by Fourier transform infrared spectroscopy (FTIR and by proton nuclear magnetic resonance (1H NMR. The thermal behaviors were determined by differential scanning calorimetry (DSC and thermogravimetric analysis (TGA. The solubility, dynamic mechanical, physical and mechanical properties of the polyamides were also investigated. The resultant polyamides have intrinsic viscosity ranging from 1.8 to 2.1 dl•g–1, their melting temperatures range from 254 to 290°C, and their glass transition temperatures obtained from dynamic mechanical analysis are in the range 87–113°C. The physical and mechanical properties of long chain semiaromatic polyamides were compared with those the PA9T. The results show that the heat resistance and the mechanical properties of poly(decamethylene-pphenylenediacetamide (PA10P are near to those of PA9T, so PA10P is a promising heat resistant engineering plastic.

  7. Oxidation of long-chain alkanes by Acetobacter rancens

    International Nuclear Information System (INIS)

    The degradation of hexadecane and tetradecane by Acetobacter rancens CCM 1774 was investigated. It was found that this strain is able to grow to a limited extent on hexadecane as a carbon source. The occurrence of n-alkanoic acids and alcohols among the reaction products of growing as well as resting cells indicates a monoterminal degradation of long-chain alkanes. Both alkane-grown and glucose-grown resting cells exhibited alkane oxidizing activities which were not influenced by chloramphenicol. This suggested a constitutive nature of the appropriate enzymes. (orig.)

  8. Human health risk assessment of long chain alcohols (LCOH)

    DEFF Research Database (Denmark)

    Veenstra, Gauke; Sanderson, Hans; Webb, Catherine; Blackburn, Karen; Schäfers, Christoph; Fisk, Peter; Kasai, Yutaka; Nielsen, Allen; Willing, Andreas

    2009-01-01

    Representative chemicals from the long chain alcohols category have been extensively tested to define their toxicological hazard properties. These chemicals show low acute and repeat dose toxicity with high-dose effects (if any) related to minimal liver toxicity. These chemicals do not show...... considered to be mild irritants and chain lengths of C18 and above are considered non-irritants. These chemicals are broadly used across the consumer products industry with highest per person consumer exposures resulting from use in personal care products. Margins of exposure adequate for the protection of...

  9. Long-chain alkane production by the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Buijs, Nicolaas A; Zhou, Yongjin J; Siewers, Verena; Nielsen, Jens

    2015-06-01

    In the past decade industrial-scale production of renewable transportation biofuels has been developed as an alternative to fossil fuels, with ethanol as the most prominent biofuel and yeast as the production organism of choice. However, ethanol is a less efficient substitute fuel for heavy-duty and maritime transportation as well as aviation due to its low energy density. Therefore, new types of biofuels, such as alkanes, are being developed that can be used as drop-in fuels and can substitute gasoline, diesel, and kerosene. Here, we describe for the first time the heterologous biosynthesis of long-chain alkanes by the yeast Saccharomyces cerevisiae. We show that elimination of the hexadecenal dehydrogenase Hfd1 and expression of a redox system are essential for alkane biosynthesis in yeast. Deletion of HFD1 together with expression of an alkane biosynthesis pathway resulted in the production of the alkanes tridecane, pentadecane, and heptadecane. Our study provides a proof of principle for producing long-chain alkanes in the industrial workhorse S. cerevisiae, which was so far limited to bacteria. We anticipate that these findings will be a key factor for further yeast engineering to enable industrial production of alkane based drop-in biofuels, which can allow the biofuel industry to diversify beyond bioethanol. PMID:25545362

  10. Structure and properties of mixtures based on long chain polyacrylate and 1-alcohol composites

    International Nuclear Information System (INIS)

    A series of phase change materials (PCMs) based on long chain polyacrylate and 1-alcohol, i.e., poly (stearyl methacrylate) and 1-tetradecanol (PSMA/C14OH) were prepared through the solution-mixing method. Thermal energy storage capacity, thermal stability and morphology of PSMA/C14OH PCMs were characterized by Fourier transform infrared spectroscopy (FTIR), polarized optical microscopy (POM), field emission scanning electron microscopy (FE-SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). DSC results demonstrated that the heat of fusion of PSMA/C14OH PCMs increased from 85.9 to 172.3 J g−1 with the weight fraction of C14OH increasing from 20 to 80 wt%. And, the thermal stability also enhanced with PSMA weight. The spherulite (ca. 250 μm) in PSMA/C14OH composites containing 60 wt% C14OH proved the compatibility between PSMA and C14OH, indicating the cocrystallization behavior of alkyl side groups appeared. The cocrystallization behavior contributes the enhanced thermal stability of PSMA/C14OH PCMs, and it is suitable as the thermal energy storage materials in the future. - Highlights: • Heat storage capability of PSMA/C14OH PCMs increased with C14OH weight. • The spherulites exhibit the weight-dependence upon C14OH. • The thermal stability of PSMA/C14OH PCMs obviously improved

  11. Extraction of beryllium sulfate by a long chain amine

    International Nuclear Information System (INIS)

    The extraction of sulfuric acid in aqueous solution by a primary amine in benzene solution, 3-9 (diethyl) - 6-amino tri-decane (D.E.T. ) - i.e., with American nomenclature 1-3 (ethyl-pentyl) - 4-ethyl-octyl amine (E.P.O.) - has made it possible to calculate the formation constants of alkyl-ammonium sulfate and acid sulfate. The formula of the beryllium and alkyl-ammonium sulfate complex formed in benzene has next been determined, for various initial acidity of the aqueous solution. Lastly, evidence has been given of negatively charged complexes of beryllium and sulfate in aqueous solution, through the dependence of the aqueous sulfate ions concentration upon beryllium extraction. The formation constant of these anionic complexes has been evaluated. (author)

  12. Fragrances by selective oxidation of long-chain alcohols

    Institute of Scientific and Technical Information of China (English)

    Alberto Villa; Carine E-Chan-Thaw; Marco Schiavoni; Sebastiano Campisi; Di Wang; Laura Prati

    2014-01-01

    The activity and the selectivity of Ru and Pt based carbon catalysts in the selective oxidation of long-chain aliphatic alcohols (C8, C10, C12) have been investigated. Ru/AC and Pt/AC always showed good initial activity, however deactivation phenomena rapidly depressed the catalytic per-formance of the catalysts. These phenomena can be limited by modification of Ru/AC and Pt/AC with Au improving the durability of the catalyst. Ru/AC and AuRu/AC showed good selectivity to the corresponding aldehyde (>95%) making these catalysts promising for fragrances manufactur-ing. The advantage in using Au modified catalyst lies on the easier regeneration procedure com-pared to the one necessary for Ru/AC. Pt/AC and AuPt/AC showed a lower selectivity to aldehyde promoting the formation of the acid and the ester formation respectively. The addition of water in the solvent system speeds up the reaction rate but drastically decreased the selectivity to aldehyde especially in the case of Pt based catalysts.

  13. Alkyl glycosides

    Czech Academy of Sciences Publication Activity Database

    Wimmer, Zdeněk; Zarevúcka, Marie; Šaman, David

    Venice, 2004. s. 20-21. [Sustainable Green Chemistry and Chemical Technology. Workshop /3./. 20.02.2004-21.02.2004, Venice] R&D Projects: GA ČR GA203/02/0166; GA MŠk OC D29.001 Keywords : alkyl glycosides Subject RIV: CC - Organic Chemistry

  14. Lymphatic recovery of exogenous oleic acid in rats on long chain or specific structured triacylglycerol diets

    DEFF Research Database (Denmark)

    Vistisen, Bodil; Mu, Huiling; Høy, Carl-Erik

    2006-01-01

    Specific structured triacylglycerols, MLM (M = medium-chain fatty acid, L = long-chain fatty acid), rapidly deliver energy and long-chain fatty acids to the body and are used for longer periods in human enteral feeding. In the present study rats were fed diets of 10 wt% MLM or LLL (L = oleic acid......-chain fatty acids from a single meal depends on the overall long-chain fatty acid composition of the habitual diet. This could have implications for enteral feeding for longer periods....

  15. Long-Chain Fatty Acid Oxidation Disorders (LC-FAOD) Extension Study for Subjects Previously Enrolled in Triheptanoin Studies.

    Science.gov (United States)

    2016-02-26

    Carnitine Palmitoyltransferase (CPT I or CPT II) Deficiency; Very Long Chain Acyl-CoA Dehydrogenase (VLCAD) Deficiency; Long-chain 3-hydroxy-acyl-CoA Dehydrogenase (LCHAD) Deficiency; Trifunctional Protein (TFP) Deficiency; Carnitine-acylcarnitine Translocase (CACT) Deficiency

  16. Research Advances in the Inhibition of Long Chain Fatty Acid to Methanogenic Activity in Anaeroic Digestion System

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    This article reviewed the inhibition mechanism of long chain fatty acid on the formation of anaerobic system, then thoroughly analyzed the inhibition factors of long chain fatty acid, and summarized the remission method to its inhibition, finally proposed some suggestions to further study on the influence of long chain fatty acid on anaerobic digestion system.

  17. Selective synthesis of linear alkylbenzene by alkylation of benzene with 1-dodecene over desilicated zeolites

    Czech Academy of Sciences Publication Activity Database

    Aslam, W.; Siddiqui, M. A. B.; Jermy, B. R.; Aitani, A.; Čejka, Jiří; Al-Khattaf, S.

    2014-01-01

    Roč. 227, MAY 2014 (2014), s. 187-197. ISSN 0920-5861 R&D Projects: GA ČR GBP106/12/G015 Institutional support: RVO:61388955 Keywords : zeolites * benzene alkylation * long-chain olefin Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.893, year: 2014

  18. UV-induced self-assembly of the inclusion complexes formed between a long-chain photochromic spiropyran and cyclodextrins

    Institute of Scientific and Technical Information of China (English)

    隋强; 周金渭; 何炜; 李仲杰; 王艳乔

    1999-01-01

    Photochromic spiropyran with a long chain alkyl substitute can form axial complexes with α-, β-, and γ-cyclodextrin, respectively. The complexes show normal photochromism. The novel property of the colored forms of the inclusion complexes is that they can assemble into dimers at relatively low concentration or J-aggregates at relatively high concentration. For α-, β-, and γ-cyclodextrin, λmax of the J-aggregates appear at 700 650, and 630 nm, respectively. The sizes of the cavities of cyclodextrins have very little effect on the spectra and decoloration kinetics of the dimers, but have great effects on the spectra of the J-aggregates. Unlike the charge transfer complex of Krongauz, the decoloration process of the dimers or J-aggregates cannot be described by an exponential or a two-exponential kinetics, but obey half-order kinetics very well. Another result that can be deduced from the kinetic analysis is that unlike the dimers formed in apolar solvents or in polymers, which consist of a color

  19. Self-assembly of amphiphilic homopolymers bearing ferrocene and carboxyl functionalities: effect of polymer concentration, β-cyclodextrin, and length of alkyl linker.

    Science.gov (United States)

    Feng, Chun; Lu, Guolin; Li, Yongjun; Huang, Xiaoyu

    2013-08-27

    Three new acrylamide monomers containing ferrocene and tert-butyl ester groups were first synthesized via multistep nucleophilic substitution reaction under mild conditions followed by reversible addition-fragmentation chain transfer (RAFT) homopolymerization to give well-defined homopolymers with narrow molecular weight distributions (M(w)/M(n) ≤ 1.36). The target amphiphilic homopolymers were obtained by the acidic hydrolysis of tert-butyoxycarbonyls to carboxyls in every repeating unit using CF3COOH. The self-assembly behaviors of these amphiphilic homopolymers bearing both ferrocene and carboxyl moieties in each repeating unit in aqueous media were investigated by transmission emission microscopy (TEM), dynamic light scattering (DLS), and atomic force microscopy (AFM). Large compound micelles with different morphologies were formed by these amphiphilic homopolymers, which consist of the corona formed by hydrophilic carboxyls and the core containing numerous reverse micelles with hydrophilic islands of carboxyls in continuous hydrophobic phase of ferrocene-based segments. The morphologies of the formed micelles could be tuned by the concentration of amphiphilic homopolymers, pH value of the solution, the length of -CH2 linker between ferrocene group and carboxyl, and the amount of β-cyclodextrin (β-CD). PMID:23977901

  20. Composition of the epicuticular waxes coating the adaxial side of Phyllostachys aurea leaves: Identification of very-long-chain primary amides.

    Science.gov (United States)

    Racovita, Radu C; Jetter, Reinhard

    2016-10-01

    The present study presents comprehensive chemical analyses of cuticular wax mixtures of the bamboo Phyllostachys aurea. The epicuticular and intracuticular waxes were sampled selectively from the adaxial side of leaves on young and old plants and investigated by gas chromatography-mass spectrometry and flame ionization detection. The epi- and intracuticular layers on young and old leaves had wax loads ranging from 1.7 μg/cm(2) to 1.9 μg/cm(2). Typical very-long-chain aliphatic wax constituents were found with characteristic chain length patterns, including alkyl esters (primarily C48), alkanes (primarily C29), fatty acids (primarily C28 and C16), primary alcohols (primarily C28) and aldehydes (primarily C30). Alicyclic wax components were identified as tocopherols and triterpenoids, including substantial amounts of triterpenoid esters. Alkyl esters, alkanes, fatty acids and aldehydes were found in greater amounts in the epicuticular layer, while primary alcohols and most terpenoids accumulated more in the intracuticular wax. Alkyl esters occurred as mixtures of metamers, combining C20 alcohol with various acids into shorter ester homologs (C36C40), and a wide range of alcohols with C22 and C24 acids into longer esters (C42C52). Primary amides were identified, with a characteristic chain length profile peaking at C30. The amides were present exclusively in the epicuticular layer and thus at or near the surface, where they may affect plant-herbivore or plant-pathogen interactions. PMID:27402630

  1. Long-chain Acylcarnitines Reduce Lung Function by Inhibiting Pulmonary Surfactant.

    Science.gov (United States)

    Otsubo, Chikara; Bharathi, Sivakama; Uppala, Radha; Ilkayeva, Olga R; Wang, Dongning; McHugh, Kevin; Zou, Ye; Wang, Jieru; Alcorn, John F; Zuo, Yi Y; Hirschey, Matthew D; Goetzman, Eric S

    2015-09-25

    The role of mitochondrial energy metabolism in maintaining lung function is not understood. We previously observed reduced lung function in mice lacking the fatty acid oxidation enzyme long-chain acyl-CoA dehydrogenase (LCAD). Here, we demonstrate that long-chain acylcarnitines, a class of lipids secreted by mitochondria when metabolism is inhibited, accumulate at the air-fluid interface in LCAD(-/-) lungs. Acylcarnitine accumulation is exacerbated by stress such as influenza infection or by dietary supplementation with l-carnitine. Long-chain acylcarnitines co-localize with pulmonary surfactant, a unique film of phospholipids and proteins that reduces surface tension and prevents alveolar collapse during breathing. In vitro, the long-chain species palmitoylcarnitine directly inhibits the surface adsorption of pulmonary surfactant as well as its ability to reduce surface tension. Treatment of LCAD(-/-) mice with mildronate, a drug that inhibits carnitine synthesis, eliminates acylcarnitines and improves lung function. Finally, acylcarnitines are detectable in normal human lavage fluid. Thus, long-chain acylcarnitines may represent a risk factor for lung injury in humans with dysfunctional fatty acid oxidation. PMID:26240137

  2. Plasma Phospholipid Long-Chain n-3 Polyunsaturated Fatty Acids and Body Weight Change

    DEFF Research Database (Denmark)

    Jakobsen, Marianne U; Dethlefsen, Claus; Due, Karen M;

    2011-01-01

    We investigated the association between the proportion of long-chain n-3 polyunsaturated fatty acids (PUFA) in plasma phospholipids from blood samples drawn at enrollment and subsequent change in body weight. Sex, age, and BMI were considered as potential effect modifiers.......We investigated the association between the proportion of long-chain n-3 polyunsaturated fatty acids (PUFA) in plasma phospholipids from blood samples drawn at enrollment and subsequent change in body weight. Sex, age, and BMI were considered as potential effect modifiers....

  3. Measuring long chain alkanes in diesel engine exhaust by thermal desorption PTR-MS

    OpenAIRE

    Erickson, M. H.; Gueneron, M.; B. T. Jobson

    2014-01-01

    A method using thermal desorption sampling and analysis by proton transfer reaction mass spectrometry (PTR-MS) to measure long chain alkanes (C12–C18) and other larger organics associated with diesel engine exhaust emissions is described. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Fragment ...

  4. Novel platinum(II) complexes of long chain aliphatic diamine ligands with oxalato as the leaving group: Comparative cytotoxic activity relative to chloride precursors

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Heveline; Barra, Carolina V.; Rocha, Fillipe V.; Fontes, Ana Paula S. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Dept. de Quimica; Lopes, Miriam T.P. [Universidade Federal deMinas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Farmacologia; Frezard, Frederic, E-mail: frezard@icb.ufmg.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisiologia e Biofisica

    2010-07-01

    Platinum complexes play an important role in the development of anticancer drugs. Their cytotoxicity can be influenced by the nature of the leaving ligands, due to the hydrolysis reaction that occurs prior to the binding of the platinum complex to DNA. Also, non-leaving groups such as lipophilic diamines may affect cellular uptake. In this work, we describe the synthesis of platinum(II) complexes having oxalato and long chain aliphatic N-alkyl ethylenediamines as ligands. The products were characterized by elemental analyses, infrared spectroscopy and {sup 1}H, {sup 13}C and {sup 195}Pt NMR spectroscopy. Biological activity was assessed against tumor cell lines (A{sub 549}, B16-F1, B16-F10, MDA-MB-231) and non-tumor cell lines (BHK-21 and CHO). The length of the carbon chain affects the cytotoxicity and the oxalato complexes were less cytotoxic than the respective chloride-containing analogues. (author)

  5. Metagenomic analysis on thermophilic biogas reactors fed with high load of Long Chain Fatty Acids (LCFA)

    DEFF Research Database (Denmark)

    Zhu, Xinyu; De Francisci, Davide; Treu, Laura;

    In anaerobic digestion systems, the accumulation of long chain fatty acids (LCFA) leads to process instability and decrease of the methane production. This detrimental condition is known to be reversible depending on the concentration of the accumulated LCFAs and mainly on the microbial consortiu...

  6. gamma-linolenic acid does not augment long-chain polyunsaturated fatty acid omega-3 status

    NARCIS (Netherlands)

    Brouwer, DAJ; Hettema, Y; van Doormaal, JJ; Muskiet, FAJ

    1998-01-01

    Augmentation of long chain polyunsaturated omega 3 fatty acid (LCPUFA omega 3) status can be reached by consumption of fish oil or by improvement of the conversion of a-linolenic acid (ALA) to LCPUFA omega 3. Since gamma-linolenic acid (GLA) might activate the rate-limiting Delta-6 desaturation, we

  7. Bioavailability of omega-3 long-chain polyunsaturated fatty acids from foods

    DEFF Research Database (Denmark)

    Mu, Huiling

    2008-01-01

    Increasing recognition of the importance of the omega-3 long chain polyunsaturated fatty acids (LCPUFA) has caused greater attention about dietary intake of these fatty acids. Fatty fish is the major dietary source of these fatty acids. Because of the low intake of fish at many places, foods...

  8. Synthesis, characterization and comparative evaluation of phenoxy ring containing long chain gemini imidazolium and pyridinium amphiphiles.

    Science.gov (United States)

    Bhadani, Avinash; Kataria, Hardeep; Singh, Sukhprit

    2011-09-01

    Two series of phenoxy ring containing long chain imidazolium and pyridinium based gemini amphiphiles have been synthesized from renewable cardanol oil having different spacers (i. e. -S-(CH(2))(n)-S-, where n is 2, 3, 4 & 6). Critical micelle concentration (cmc) of these new gemini amphiphiles has been determined by conductivity method. Further, these new cationic amphiphiles have been evaluated for their DNA binding capability by agarose gel electrophoresis, ethidium bromide exclusion experiments and transmission electron microscopy (TEM). The cytotoxicity of these new amphiphiles have been evaluated by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Comparative studies of these phenoxy ring containing long chain gemini imidazolium amphiphiles and their pyridinium analogues depicted low cmc values of the later but greater DNA interaction capability and low cytotoxicity of the former series of amphiphiles. PMID:21676409

  9. Mechanism of long chain monoenoic fatty acids acting on the energy metabolism of heart

    International Nuclear Information System (INIS)

    The oxidation of 1-14C-erucic (Csub(22:1)) and 1-14C-nervonic (Csub(24:1)) acid was studied compared to 1-14C-palmitic and -oleic acid in isolated rat and pig heart mitochondria. After mitochondrial incubation with the albumin-bound fatty acids only small amounts of 14CO2 developed from the oxidation of the long chain monoenoic acids as compared to palmitic or oleic acid. The slow down of the oxidation rate was more pronounced in rat than in pig heart mitochondria. The oxidation of palmitic or oleic acid was not found to be inhibited by the C20-C24-monoeneic acids, whereas palmitic or oleic acid inhibited the oxidation of erucic acid competitively. From present findings an idea may be developed of the interference on fatty acid metabolism in heart muscle by erucic and other long chain monenoic acids. (orig.)

  10. The Staphylococcus aureus Response to Unsaturated Long Chain Free Fatty Acids: Survival Mechanisms and Virulence Implications

    OpenAIRE

    Kenny, John G.; Deborah Ward; Elisabet Josefsson; Ing-Marie Jonsson; Jason Hinds; Rees, Huw H.; Lindsay, Jodi A; Andrej Tarkowski; Horsburgh, Malcolm J.

    2009-01-01

    Staphylococcus aureus is an important human commensal and opportunistic pathogen responsible for a wide range of infections. Long chain unsaturated free fatty acids represent a barrier to colonisation and infection by S. aureus and act as an antimicrobial component of the innate immune system where they are found on epithelial surfaces and in abscesses. Despite many contradictory reports, the precise anti-staphylococcal mode of action of free fatty acids remains undetermined. In this study, t...

  11. Role of Dietary Long-Chain Polyunsaturated Fatty Acids in Infant Allergies and Respiratory Diseases

    OpenAIRE

    Shek, Lynette P.; Mary Foong-Fong Chong; Jia Yi Lim; Shu-E Soh; Yap-Seng Chong

    2012-01-01

    Maternal nutrition has critical effects on the developing structures and functions of the fetus. Malnutrition during pregnancy can result in low birth weight and small for gestational age babies, increase risk for infection, and impact the immune system. Long-chain polyunsaturated fatty acids (PUFAs) have been reported to have immunomodulatory effects. Decreased consumption of omega-6 PUFAs, in favor of more anti-inflammatory omega-3 PUFAs in modern diets, has demonstrated the potential prote...

  12. New strategies for optimal methane production from long chain fatty acids

    OpenAIRE

    Cavaleiro, A. J.; Salvador, A. F.; Silva, Sérgio; Pereira, M.A.; Sousa, D.Z.; Alves, M. M.

    2012-01-01

    High methane production can be expected from biodegradation of long chain fatty acids (LCFA) in anaerobic bioreactors; however, in practice, this process is limited by LCFA accumulation onto the sludge. To optimize methane production from LCFA-rich wastewater, two novel strategies were tested: (i) bioreactor start-up based on the alternation of continuous-feeding phases with batch-degradation phases, and (ii) bioreactor bioaugmentation with the LCFAdegrading bacterium Syntrophomonas zehnderi....

  13. Modification of nano-sized layered double hydroxides by long-chain organic aliphatic surfactants

    OpenAIRE

    RAMASAMY ANBARASAN; SEUNG SOON IM; WANDUC LEE

    2008-01-01

    The inter-layer anion of layered double hydroxides (LDH) with a hydrotalcite (HT)-like structure was ion-exchanged with various organic surfactants, particularly with long chain aliphatic surfactants. After the ion-exchange process, the basal spacing of the LDH was increased and the increase of the basal spacing depended on various factors, such as the intercalation capacity functionality and orientation capability of the surfactant. Of the employed surfactants, stearic acid intercalated LDH ...

  14. Serum long-chain omega-3 polyunsaturated fatty acids and risk of orthostatic hypotension.

    Science.gov (United States)

    Nyantika, Asenath N; Tuomainen, Tomi-Pekka; Kauhanen, Jussi; Voutilainen, Sari; Virtanen, Jyrki K

    2016-07-01

    Long-chain omega-3 polyunsaturated fatty acids (PUFAs) from fish have been shown to lower blood pressure. However, there is little information about the association with orthostatic hypotension, for which hypertension is a risk factor. We investigated the associations between serum long-chain omega-3 PUFAs and orthostatic hypotension in 1666 middle-aged or older men and women free of cardiovascular disease (CVD), diabetes or hypertension in 1998-2001 in the Kuopio Ischemic Heart Disease Risk Factor Study (KIHD) in eastern Finland. We also investigated the associations with mercury exposure, a major source of which is fish, and which has been associated with higher CVD risk in KIHD. Orthostatic hypotension was defined as decrease in systolic blood pressure of at least 20 mm Hg or diastolic blood pressure of at least 10 mm Hg within 1 min of standing. Orthostatic hypotension was found in 146 participants (8.8%). The mean serum concentrations were 1.67% (s.d. 0.92) for eicosapentaenoic acid, 0.79% (s.d. 0.16) for docosapentaenoic acid (DPA) and 2.78 (s.d. 0.92) for docosahexaenoic acid of all serum fatty acids. The mean pubic hair mercury concentration was 1.5 μg g(-1) (s.d. 1.6). We did not find statistically significant associations between the serum long-chain omega-3 PUFAs or pubic hair mercury and risk of orthostatic hypotension, except for DPA. Those in the highest vs. the lowest serum DPA tertile had multivariate-adjusted 41% lower odds for orthostatic hypotension (95% confidence interval 7-63%, P-trend=0.02). Serum long-chain omega-3 PUFAs or mercury exposure were not associated with the risk of orthostatic hypotension, except for the inverse association with DPA. PMID:26911234

  15. Long-chain acylcarnitines determine ischaemia/reperfusion-induced damage in heart mitochondria.

    Science.gov (United States)

    Liepinsh, Edgars; Makrecka-Kuka, Marina; Volska, Kristine; Kuka, Janis; Makarova, Elina; Antone, Unigunde; Sevostjanovs, Eduards; Vilskersts, Reinis; Strods, Arnis; Tars, Kaspars; Dambrova, Maija

    2016-05-01

    The accumulation of long-chain fatty acids (FAs) and their CoA and carnitine esters is observed in the ischaemic myocardium after acute ischaemia/reperfusion. The aim of the present study was to identify harmful FA intermediates and their detrimental mechanisms of action in mitochondria and the ischaemic myocardium. In the present study, we found that the long-chain acyl-CoA and acylcarnitine content is increased in mitochondria isolated from an ischaemic area of the myocardium. In analysing the FA derivative content, we discovered that long-chain acylcarnitines, but not acyl-CoAs, accumulate at concentrations that are harmful to mitochondria. Acylcarnitine accumulation in the mitochondrial intermembrane space is a result of increased carnitine palmitoyltransferase 1 (CPT1) and decreased carnitine palmitoyltransferase 2 (CPT2) activity in ischaemic myocardium and it leads to inhibition of oxidative phosphorylation, which in turn induces mitochondrial membrane hyperpolarization and stimulates the production of reactive oxygen species (ROS) in cardiac mitochondria. Thanks to protection mediated by acyl-CoA-binding protein (ACBP), the heart is much better guarded against the damaging effects of acyl-CoAs than against acylcarnitines. Supplementation of perfusion buffer with palmitoylcarnitine (PC) before occlusion resulted in a 2-fold increase in the acylcarnitine content of the heart and increased the infarct size (IS) by 33%. A pharmacologically induced decrease in the mitochondrial acylcarnitine content reduced the IS by 44%. Long-chain acylcarnitines are harmful FA intermediates, accumulating in ischaemic heart mitochondria and inducing inhibition of oxidative phosphorylation. Therefore, decreasing the acylcarnitine content via cardioprotective drugs may represent a novel treatment strategy. PMID:26936967

  16. Very long chain acyl-coenzyme A dehydrogenase deficiency with adult onset

    DEFF Research Database (Denmark)

    Smelt, A H; Poorthuis, B J; Onkenhout, W; Scholte, H R; Andresen, B S; van Duinen, S G; Gregersen, N; Wintzen, A R

    1998-01-01

    Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9), tetrade...... be due to residual enzyme activity as a consequence of the two missense mutations. Treatment with L-carnitine and medium chain triglycerides in the diet did not reduce the attacks of rhabdomyolysis....

  17. Gating of the Mitochondrial Permeability Transition Pore by Long Chain Fatty Acyl Analogs in Vivo*

    OpenAIRE

    Samovski, Dmitri; Kalderon, Bella; Yehuda-Shnaidman, Einav; Bar-Tana, Jacob

    2009-01-01

    The role played by long chain fatty acids (LCFA) in promoting energy expenditure is confounded by their dual function as substrates for oxidation and as putative classic uncouplers of mitochondrial oxidative phosphorylation. LCFA analogs of the MEDICA (MEthyl-substituted DICarboxylic Acids) series are neither esterified into lipids nor β-oxidized and may thus simulate the uncoupling activity of natural LCFA in vivo, independently of their substrate role. Treatment of rats or cell lines with M...

  18. Molecular assessment of complex microbial communities degrading long chain fatty acids in methanogenic bioreactors

    OpenAIRE

    Sousa, D.Z.; Pereira, M.A.; Smidt, Hauke; Stams, A.J.M.; Alves, M. M.

    2007-01-01

    Microbial diversity of anaerobic sludge after extended contact with long chain fatty acids (LCFA) was studied using molecular approaches. Samples containing high amounts of accumulated LCFA were obtained after continuous loading of two bioreactors with oleate or with palmitate. These sludge samples were then incubated in batch assays to allow degradation of the biomass-associated LCFA. In addition, sludge used as inoculum for the reactors was also characterized. Predominant ...

  19. Microbial communities involved in anaerobic degradation of unsaturated or saturated long chain fatty acids

    OpenAIRE

    Sousa, D.Z.; Pereira, M.A.; Stams, A.J.M.; Alves, M. M.; Smidt, H.

    2007-01-01

    Anaerobic long-chain fatty acid (LCFA)-degrading bacteria were identified by combining selective enrichment studies with molecular approaches. Two distinct enrichment cultures growing on unsaturated and saturated LCFAs were obtained by successive transfers in medium containing oleate and palmitate, respectively, as the sole carbon and energy sources. Changes in the microbial composition during enrichment were analyzed by denaturing gradient gel electrophoresis (DGGE) profiling of PCR...

  20. Genes involved in long-chain alkene biosynthesis in Micrococcus luteus

    Energy Technology Data Exchange (ETDEWEB)

    Beller, Harry R.; Goh, Ee-Been; Keasling, Jay D.

    2010-01-07

    Aliphatic hydrocarbons are highly appealing targets for advanced cellulosic biofuels, as they are already predominant components of petroleum-based gasoline and diesel fuels. We have studied alkene biosynthesis in Micrococcus luteus ATCC 4698, a close relative of Sarcina lutea (now Kocuria rhizophila), which four decades ago was reported to biosynthesize iso- and anteiso branched, long-chain alkenes. The underlying biochemistry and genetics of alkene biosynthesis were not elucidated in those studies. We show here that heterologous expression of a three-gene cluster from M. luteus (Mlut_13230-13250) in a fatty-acid overproducing E. coli strain resulted in production of long-chain alkenes, predominantly 27:3 and 29:3 (no. carbon atoms: no. C=C bonds). Heterologous expression of Mlut_13230 (oleA) alone produced no long-chain alkenes but unsaturated aliphatic monoketones, predominantly 27:2, and in vitro studies with the purified Mlut_13230 protein and tetradecanoyl-CoA produced the same C27 monoketone. Gas chromatography-time of flight mass spectrometry confirmed the elemental composition of all detected long-chain alkenes and monoketones (putative intermediates of alkene biosynthesis). Negative controls demonstrated that the M. luteus genes were responsible for production of these metabolites. Studies with wild-type M. luteus showed that the transcript copy number of Mlut_13230-13250 and the concentrations of 29:1 alkene isomers (the dominant alkenes produced by this strain) generally corresponded with bacterial population over time. We propose a metabolic pathway for alkene biosynthesis starting with acyl-CoA (or -ACP) thioesters and involving decarboxylative Claisen condensation as a key step, which we believe is catalyzed by OleA. Such activity is consistent with our data and with the homology (including the conserved Cys-His-Asn catalytic triad) of Mlut_13230 (OleA) to FabH (?-ketoacyl-ACP synthase III), which catalyzes decarboxylative Claisen condensation during

  1. Flocculation of fine fluorite particles with Corynebacterium xerosis and commercial long chain polymers

    Directory of Open Access Journals (Sweden)

    Rigo Lisandra N.

    2002-01-01

    Full Text Available This work aimed to study, comparatively, the flocculation of fluorite particles with Corynebacterium xerosis cells and three commercial long chain polymers. Best flocculation results were obtained with cells of C. xerosis and with an anionic polyacrylamide. Both were effective in solids removal and water clarification, although flocculation with C. xerosis cells requires a higher dosage of reagent per mass unit of processed ore.

  2. Orphan drugs in development for long-chain fatty acid oxidation disorders: challenges and progress

    Directory of Open Access Journals (Sweden)

    Sun A

    2015-04-01

    Full Text Available Angela Sun, J Lawrence Merritt II Department of Pediatrics, University of Washington, Seattle, WA, USA Abstract: Fatty acid oxidation disorders are inborn errors of metabolism resulting in failure of ß-oxidation within or transport of fatty acids into the mitochondria. The long-chain fatty acid oxidation disorders are characterized by variable presentations ranging from newborn cardiomyopathy, to infantile hypoketotic hypoglycemia resulting from liver involvement, to skeletal myopathy often resulting in rhabdomyolysis in adolescents and adults. Treatments for these long-chain fatty acid oxidation disorders have typically focused upon avoidance of fasting with dietary fat restriction and medium-chain triglyceride supplementation. These treatments have resulted in only a partial response with improvements in hypoglycemia, reduction in frequency of rhabdomyolysis, and improvement in cardiomyopathy with early therapy, but significant risk remains. Recent advances in therapies for long-chain fatty acid oxidation disorders are reviewed in this article. These include sodium D,L-3-hydroxybutyrate, triheptanoin, gene therapy, and bezafibrates. Sodium D,L-3-hydroxybutyrate has shown clinical effect, with improvements in muscle tone, neurological abnormalities, and some cases of cardiomyopathy and leukodystrophy. Triheptanoin has been used as an alternative medium-chain triglyceride in a number of fatty acid oxidation disorders and has shown promising findings in the treatment of cardiomyopathy and hypoglycemia. However, it does not significantly reduce episodes of rhabdomyolysis. Gene therapy has been shown to improve acylcarnitine levels in very-long-chain acyl-coenzyme A dehydrogenase deficiency mouse models, with preservation of glucose levels. Bezafibrates have shown improvements in acylcarnitine concentrations in fibroblast studies, but clinical observations have not demonstrated consistent effects. Together, these treatments have shown some

  3. Unique plasma metabolomic signatures of individuals with inherited disorders of long-chain fatty acid oxidation.

    Science.gov (United States)

    McCoin, Colin S; Piccolo, Brian D; Knotts, Trina A; Matern, Dietrich; Vockley, Jerry; Gillingham, Melanie B; Adams, Sean H

    2016-05-01

    Blood and urine acylcarnitine profiles are commonly used to diagnose long-chain fatty acid oxidation disorders (FAOD: i.e., long-chain hydroxy-acyl-CoA dehydrogenase [LCHAD] and carnitine palmitoyltransferase 2 [CPT2] deficiency), but the global metabolic impact of long-chain FAOD has not been reported. We utilized untargeted metabolomics to characterize plasma metabolites in 12 overnight-fasted individuals with FAOD (10 LCHAD, two CPT2) and 11 healthy age-, sex-, and body mass index (BMI)-matched controls, with the caveat that individuals with FAOD consume a low-fat diet supplemented with medium-chain triglycerides (MCT) while matched controls consume a typical American diet. In plasma 832 metabolites were identified, and partial least squared-discriminant analysis (PLS-DA) identified 114 non-acylcarnitine variables that discriminated FAOD subjects and controls. FAOD individuals had significantly higher triglycerides and lower specific phosphatidylethanolamines, ceramides, and sphingomyelins. Differences in phosphatidylcholines were also found but the directionality differed by metabolite species. Further, there were few differences in non-lipid metabolites, indicating the metabolic impact of FAOD specifically on lipid pathways. This analysis provides evidence that LCHAD/CPT2 deficiency significantly alters complex lipid pathway flux. This metabolic signature may provide new clinical tools capable of confirming or diagnosing FAOD, even in subjects with a mild phenotype, and may provide clues regarding the biochemical and metabolic impact of FAOD that is relevant to the etiology of FAOD symptoms. PMID:26907176

  4. Trans fatty acids may impair biosynthesis of long-chain polyunsaturates and growth in man.

    Science.gov (United States)

    Koletzko, B

    1992-04-01

    Human diet contains large amounts of trans fatty acids originating primarily from hydrogenated fats. Consumption of trans fatty acids is considered safe for man, but side effects, including impaired biosynthesis of long-chain polyunsaturated fatty acids with 20 and 22 carbon atoms and reduced growth have been observed in animals. We studied whether or not there are indications of untoward effects of trans fatty acids in 29 premature infants (birth weight 1700 +/- 127 g, gestational age 33.6 +/- 1.4 weeks, mean +/- SD). Plasma samples obtained on day 4 of life were analysed for fatty acid composition. Trans octadecenoic acid and total trans fatty acids in plasma lipid fractions (% wt/wt) were not related to the precursor essential fatty acids linoleic and alpha-linolenic acids but correlated inversely to n - 3 and n - 6 long-chain polyunsaturated fatty acids and to the product/substrate ratios of long-chain polyunsaturate biosynthesis. Trans fatty acids were also inversely correlated to birth weight but not to gestational age. These data indicate a potential impairment of essential fatty acid metabolism and early growth by trans isomers in man, and question the safety of high dietary trans isomer intakes during pregnancy and the perinatal period. PMID:1606388

  5. Relationship between orbital energy gaps and excitation energies for long-chain systems.

    Science.gov (United States)

    Tsuneda, Takao; Singh, Raman K; Nakata, Ayako

    2016-06-15

    The difference between the excitation energies and corresponding orbital energy gaps, the exciton binding energy, is investigated based on time-dependent (TD) density functional theory (DFT) for long-chain systems: all-trans polyacetylenes and linear oligoacenes. The optimized geometries of these systems indicate that bond length alternations significantly depend on long-range exchange interactions. In TDDFT formalism, the exciton binding energy comes from the two-electron interactions between occupied and unoccupied orbitals through the Coulomb-exchange-correlation integral kernels. TDDFT calculations show that the exciton binding energy is significant when long-range exchange interactions are involved. Spin-flip (SF) TDDFT calculations are then carried out to clarify double-excitation effects in these excitation energies. The calculated SF-TDDFT results indicate that double-excitation effects significantly contribute to the excitations of long-chain systems. The discrepancies between the vertical ionization potential minus electron affinity (IP-EA) values and the HOMO-LUMO excitation energies are also evaluated for the infinitely long polyacetylene and oligoacene using the least-square fits to estimate the exciton binding energy of infinitely long systems. It is found that long-range exchange interactions are required to give the exciton binding energy of the infinitely long systems. Consequently, it is concluded that long-range exchange interactions neglected in many DFT calculations play a crucial role in the exciton binding energies of long-chain systems, while double-excitation correlation effects are also significant to hold the energy balance of the excitations. © 2016 Wiley Periodicals, Inc. PMID:27010365

  6. Suppression of adipose lipolysis by long-chain fatty acid analogs

    OpenAIRE

    Kalderon, Bella; Azazmeh, Narmen; Azulay, Nili; Vissler, Noam; Valitsky, Michael; Bar-Tana, Jacob

    2012-01-01

    Agonist-induced lipolysis of adipose fat is robustly inhibited by insulin or by feedback inhibition by the long-chain fatty acids (LCFA) produced during lipolysis. However, the mode of action of LCFA in suppressing adipose lipolysis is not clear. β,β’-Tetramethyl hexadecanedioic acid (Mββ/ EDICA16) is a synthetic LCFA that is neither esterified into lipids nor β-oxidized, and therefore, it was exploited for suppressing agonist-induced lipolysis in analogy to natural LCFA. Mββ is shown here to...

  7. A severe genotype with favourable outcome in very long chain acyl-CoA dehydrogenase deficiency

    DEFF Research Database (Denmark)

    Touma, E H; Rashed, M S; Vianey-Saban, C; Sakr, A; Divry, P; Gregersen, N; Andresen, B S

    2001-01-01

    A patient with very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is reported. He had a severe neonatal presentation and cardiomyopathy. He was found to be homozygous for a severe mutation with no residual enzyme activity. Tandem mass spectrometry on dried blood spots revealed increased lo...... chain acylcarnitines. VLCAD enzyme activity was severely decreased to 2% of control levels. Dietary management consisted of skimmed milk supplemented with medium chain triglycerides and L-carnitine. Outcome was good and there was no acute recurrence....

  8. Bioavailability of omega-3 long-chain polyunsaturated fatty acids from foods

    DEFF Research Database (Denmark)

    Mu, Huiling

    2008-01-01

    Increasing recognition of the importance of the omega-3 long chain polyunsaturated fatty acids (LCPUFA) has caused greater attention about dietary intake of these fatty acids. Fatty fish is the major dietary source of these fatty acids. Because of the low intake of fish at many places, foods...... enriched with omega-3 LCPUFA can be good alternatives to improve the intake of these fatty acids. Effects of lipid structures and food matrices on bioavailability of omega-3 LCPUFA have been investigated. Short term studies showed that both lipid structure and food matrix affect the bioavailability of...

  9. Rom2-dependent phosphorylation of Elo2 controls the abundance of very long chain fatty acids

    DEFF Research Database (Denmark)

    Olson, Daniel K; Fröhlich, Florian; Christiano, Romain;

    2015-01-01

    Sphingolipids are essential components of eukaryotic membranes, where they serve to maintain membrane integrity. They are important components of membrane trafficking and function in signaling as messenger molecules. Sphingolipids are synthesized de novo from very long chain fatty acids (VLCFA) and...... that Elo2, a key enzyme of VLCFA synthesis, is controlled by signaling of the guanine nucleotide exchange factor Rom2, initiating at the plasma membrane. This pathway controls Elo2 phosphorylation state and VLCFA synthesis. Our data identify a regulatory mechanism for coordinating VLCFA synthesis with...

  10. Retinal dystrophy in long chain 3-hydroxy-acyl-CoA dehydrogenase deficiency

    OpenAIRE

    Schrijver-Wieling, I.; Rens, G.H.B.M. van; Wittebol-Post, D.; Smeitink, J.A.M.; De Jager, J P; Klerk, J.B.C. de; van Lith, G. H M

    1997-01-01

    BACKGROUND—Long chain 3-hydroxy-acyl-CoA dehydrogenase (LCHAD) is one of the enzymes involved in the breakdown of fatty acids. A deficiency of this enzyme is associated with life threatening episodes of hypoketotic hypoglycaemia during prolonged fasting. Neuropathy and retinopigmentary changes were mentioned in only a few cases.
METHODS—The case histories of two girls, aged 8 and 15 years, with LCHAD deficiency are reported.
RESULTS—Both children with LCHAD deficiency exhibited extensive macu...

  11. Syntheses, Characterization, Physical and Biological Properties of Long-chain, Water-soluble, Dendritic Amphiphiles

    OpenAIRE

    Williams, André Arvin

    2008-01-01

    In this project, we have designed and synthesized a new series of long-chain, water-soluble, dendritic, anionic amphiphiles [3CAmn, RCONHC(CH2CH2COOH)3, R= CnH2n+1] to alleviate the low aqueous solubility of fatty acids. The dendritic-tricarboxlyato headgroup improves aqueous solubility and allows us to measure the intrinsic biological activity of our amphiphiles without the potential hindrance of low aqueous solubility. The aqueous solubilities of the anionic amphiphiles have been measured...

  12. Dietary long-chain polyunsaturated fatty acids upregulate expression of FADS3 transcripts

    OpenAIRE

    Reardon, Holly T; Hsieh, Andrea T.; Park, Woo Jung; Kothapalli, Kumar S. D.; Anthony, Joshua C.; Nathanielsz, Peter W.; Brenna, J. Thomas

    2012-01-01

    The fatty acid desaturase (FADS) gene family at 11q12-13.1 includes FADS1 and FADS2, both known to mediate biosynthesis of omega-3 and omega-6 long-chain polyunsaturated fatty acids (LCPUFA). FADS3 is a putative desaturase due to its sequence similarity with FADS1 and FADS2, but its function is unknown. We have previously described 7 FADS3 alternative transcripts (AT) and 1 FADS2 AT conserved across multiple species. This study examined the effect of dietary LCPUFA levels on liver FADS gene e...

  13. The association of serum long-chain n-3 PUFA and hair mercury with exercise cardiac power in men.

    Science.gov (United States)

    Tajik, Behnam; Kurl, Sudhir; Tuomainen, Tomi-Pekka; Virtanen, Jyrki K

    2016-08-01

    Long-chain n-3 PUFA from fish and exercise capacity are associated with CVD risk. Fish, especially large and old predatory fish, may contain Hg, which may attenuate the inverse association of long-chain n-3 PUFA with CVD. However, the associations of long-chain n-3 PUFA or Hg exposure with exercise capacity are not well known. We aimed to evaluate the associations of serum long-chain n-3 PUFA EPA, docosapentaenoic acid (DPA) and DHA and hair Hg with exercise cardiac power (ECP, a ratio of VO2max:maximal systolic blood pressure (SBP) during an exercise test), a measure for exercise capacity. For this, data from the population-based Kuopio Ischaemic Heart Disease Risk Factor Study were analysed cross-sectionally in order to determine the associations between serum long-chain n-3 PUFA, hair Hg and ECP in 1672 men without CVD, aged 42-60 years. After multivariate adjustments, serum total long-chain n-3 PUFA concentration was associated with higher ECP and VO2max (P trend across quartiles=0·04 and P trend=0·02, respectively), but not with maximal SBP (P trend=0·69). Associations were generally similar when EPA, DPA and DHA were evaluated individually. Hair Hg was not associated with ECP, VO2max or maximal SBP. However, the associations of total long-chain n-3 PUFA (P interaction=0·03) and EPA (P interaction=0·02) with higher VO2max were stronger among men with lower hair Hg. Higher serum long-chain n-3 PUFA concentration, mainly a marker for fish consumption in this study population, was associated with higher ECP and VO2max in middle-aged men from eastern Finland. PMID:27255152

  14. Dependence of the product chain-length on detergents for long-chain E-polyprenyl diphosphate synthases

    OpenAIRE

    Pan, Jian-Jung; Ramamoorthy, Gurusankar; Poulter, C. Dale

    2013-01-01

    Long-chain E-polyprenyl diphosphate synthases (E-PDS) catalyze repetitive addition of isopentenyl diphosphate (IPP) to the growing prenyl chain of an allylic diphosphate. The polyprenyl diphosphate products are required for the biosynthesis of ubiquinones and menaquinones required for electron transport during oxidative phosphorylation to generate ATP. In vitro, the long-chain PDSs require addition of phospholipids or detergents to the assay buffer to enhance product release and maintain effi...

  15. Nutritional evaluation of microalgae oils rich in omega-3 long chain polyunsaturated fatty acids as an alternative for fish oil

    OpenAIRE

    Ryckebosch, Eline; Bruneel, Charlotte; Termote-Verhalle, Romina; Goiris, Koen; Muylaert, Koenraad; Foubert, Imogen

    2014-01-01

    The purpose of this work was to evaluate the nutritional value of the total lipid extract of different omega-3 long chain polyunsaturated fatty acids producing photoautotrophic microalgae in one study. It was shown that microalgae oils from Isochrysis, Nannochloropsis, Phaeodactylum, Pavlova and Thalassiosira contain sufficient omega-3 LC-PUFA to serve as an alternative for fish oil, which was used as the ‘golden standard’. In the microalgae oils an important part of the omega-3 long chain po...

  16. Long-chain alkenones in sulfate lakes and its paleoclimatic implications

    Institute of Scientific and Technical Information of China (English)

    SUN Qing; CHU Guoqiang; LI Shengqiang; Lü Caifen; ZHENG Mianping

    2004-01-01

    The proxy of index is widely applied to reconstructing paleotemperature in the marine environment. However, the long-chain alkenones (LCAs) research is rarely reported in the liminic system. In this paper, we studied LCAs in the surface sediments (0-10 cm) of nine sulfate lakes in the Inner Mongolia Autonomous Region, Xinjiang Uygur Autonomous Region and Qinghai Province, China. LCAs are detected in eight of the nine lakes, except a dry salt lake - Lake Lop. The result shows that LCAs might be universal in the sulfate lakes. In most of the surface samples, the sequence of the abundance of the long-chain alkenones is C37(C38(C39(C40. And C37:4 methyl ketone is a predominant compound in the C37 alkenone homologue. Based on regression analysis of -ratios and the average annual, seasonal (spring, summer, autumn, winter) temperatures, the linear relativity of -ratios and mean annual temperatures is superior to the others, and the correlation coefficient is 0.88 (r2 = 0.88). The linear relationship of and the average annual temperature in different water chemistry environments suggests that the mechanisms controlling index in the saline lakes might be the same as those in the ocean environment. The alkenone unsaturation could become an important paleotemperature proxy in the lacustrine environment.

  17. Bacterial Long-Chain Polyunsaturated Fatty Acids: Their Biosynthetic Genes, Functions, and Practical Use

    Directory of Open Access Journals (Sweden)

    Kiyohito Yoshida

    2016-05-01

    Full Text Available The nutritional and pharmaceutical values of long-chain polyunsaturated fatty acids (LC-PUFAs such as arachidonic, eicosapentaenoic and docosahexaenoic acids have been well recognized. These LC-PUFAs are physiologically important compounds in bacteria and eukaryotes. Although little is known about the biosynthetic mechanisms and functions of LC-PUFAs in bacteria compared to those in higher organisms, a combination of genetic, bioinformatic, and molecular biological approaches to LC-PUFA-producing bacteria and some eukaryotes have revealed the notably diverse organization of the pfa genes encoding a polyunsaturated fatty acid synthase complex (PUFA synthase, the LC-PUFA biosynthetic processes, and tertiary structures of the domains of this enzyme. In bacteria, LC-PUFAs appear to take part in specific functions facilitating individual membrane proteins rather than in the adjustment of the physical fluidity of the whole cell membrane. Very long chain polyunsaturated hydrocarbons (LC-HCs such as hentriacontanonaene are considered to be closely related to LC-PUFAs in their biosynthesis and function. The possible role of LC-HCs in strictly anaerobic bacteria under aerobic and anaerobic environments and the evolutionary relationships of anaerobic and aerobic bacteria carrying pfa-like genes are also discussed.

  18. Bacterial Long-Chain Polyunsaturated Fatty Acids: Their Biosynthetic Genes, Functions, and Practical Use

    Science.gov (United States)

    Yoshida, Kiyohito; Hashimoto, Mikako; Hori, Ryuji; Adachi, Takumi; Okuyama, Hidetoshi; Orikasa, Yoshitake; Nagamine, Tadashi; Shimizu, Satoru; Ueno, Akio; Morita, Naoki

    2016-01-01

    The nutritional and pharmaceutical values of long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic, eicosapentaenoic and docosahexaenoic acids have been well recognized. These LC-PUFAs are physiologically important compounds in bacteria and eukaryotes. Although little is known about the biosynthetic mechanisms and functions of LC-PUFAs in bacteria compared to those in higher organisms, a combination of genetic, bioinformatic, and molecular biological approaches to LC-PUFA-producing bacteria and some eukaryotes have revealed the notably diverse organization of the pfa genes encoding a polyunsaturated fatty acid synthase complex (PUFA synthase), the LC-PUFA biosynthetic processes, and tertiary structures of the domains of this enzyme. In bacteria, LC-PUFAs appear to take part in specific functions facilitating individual membrane proteins rather than in the adjustment of the physical fluidity of the whole cell membrane. Very long chain polyunsaturated hydrocarbons (LC-HCs) such as hentriacontanonaene are considered to be closely related to LC-PUFAs in their biosynthesis and function. The possible role of LC-HCs in strictly anaerobic bacteria under aerobic and anaerobic environments and the evolutionary relationships of anaerobic and aerobic bacteria carrying pfa-like genes are also discussed. PMID:27187420

  19. Conversion of raw lignocellulosic biomass into branched long-chain alkanes through three tandem steps.

    Science.gov (United States)

    Li, Chunrui; Ding, Daqian; Xia, Qineng; Liu, Xiaohui; Wang, Yanqin

    2016-07-01

    Synthesis of branched long-chain alkanes from renewable biomass has attracted intensive interest in recent years, but the feedstock for this synthesis is restricted to platform chemicals. Here, we develop an effective and energy-efficient process to convert raw lignocellulosic biomass (e.g., corncob) into branched diesel-range alkanes through three tandem steps for the first time. Furfural and isopropyl levulinate (LA ester) were prepared from hemicellulose and cellulose fractions of corncob in toluene/water biphasic system with added isopropanol, which was followed by double aldol condensation of furfural with LA ester into C15 oxygenates and the final hydrodeoxygenation of C15 oxygenates into branched long-chain alkanes. The core point of this tandem process is the addition of isopropanol in the first step, which enables the spontaneous transfer of levulinic acid (LA) into the toluene phase in the form of LA ester through esterification, resulting in LA ester co-existing with furfural in the same phase, which is the basis for double aldol condensation in the toluene phase. Moreover, the acidic aqueous phase and toluene can be reused and the residues, including lignin and humins in aqueous phase, can be separated and carbonized to porous carbon materials. PMID:27241180

  20. Long-chain amine-templated synthesis of gallium sulfide and gallium selenide nanotubes

    Science.gov (United States)

    Seral-Ascaso, A.; Metel, S.; Pokle, A.; Backes, C.; Zhang, C. J.; Nerl, H. C.; Rode, K.; Berner, N. C.; Downing, C.; McEvoy, N.; Muñoz, E.; Harvey, A.; Gholamvand, Z.; Duesberg, G. S.; Coleman, J. N.; Nicolosi, V.

    2016-06-01

    We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization.We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01663d

  1. DISTINCT TRANSCRIPTIONAL REGULATION OF LONG-CHAIN ACYL-COA SYNTHETASE ISOFORMS AND CYTOSOLIC THIOESTERASE 1 IN THE RODENT HEART BY FATTY ACIDS AND INSULIN

    Science.gov (United States)

    The molecular mechanism(s) responsible for channeling long-chain fatty acids (LCFAs) into oxidative versus nonoxidative pathways is (are) poorly understood in the heart. Intracellular LCFAs are converted to long-chain fatty acyl-CoAs (LCFA-CoAs) by a family of long-chain acyl-CoA synthetases (ACSLs)...

  2. Fluorescent assay for oxytetracycline based on a long-chain aptamer assembled onto reduced graphene oxide

    International Nuclear Information System (INIS)

    We report on a fluorescent assay for oxytetracycline (OTC) using a fluorescein-labeled long-chain aptamer assembled onto reduced graphene oxide (rGO). The π-π stacking interaction between aptamer and rGO causes the fluorescence of the label to be almost completely quenched via energy transfer so that the system has very low background fluorescence. The addition of OTC leads to the formation of G-quadruplex OTC complexes and prevents the adsorption of labeled aptamer on the surface of rGO. As a result, fluorescence is restored, and this effect allows for a quantitative assay of OTC over the 0.1–2 μM concentration range and with a detection limit of 10 nM. This method is simple, rapid, selective and sensitive. It may be applied to other small molecule analytes by applying appropriate aptamers. (author)

  3. Modification of nano-sized layered double hydroxides by long-chain organic aliphatic surfactants

    Directory of Open Access Journals (Sweden)

    RAMASAMY ANBARASAN

    2008-03-01

    Full Text Available The inter-layer anion of layered double hydroxides (LDH with a hydrotalcite (HT-like structure was ion-exchanged with various organic surfactants, particularly with long chain aliphatic surfactants. After the ion-exchange process, the basal spacing of the LDH was increased and the increase of the basal spacing depended on various factors, such as the intercalation capacity functionality and orientation capability of the surfactant. Of the employed surfactants, stearic acid intercalated LDH showed the highest increase of the basal spacing, which was confirmed by XRD analysis. FTIR results supported the interaction of the surfactants with the LDH. In addition, an increase in the thermal stability of the dodecanedioic acid intercalated HT was evidenced by the TGA method.

  4. Long-chain acyl-CoA esters in metabolism and signaling

    DEFF Research Database (Denmark)

    Neess, Ditte; Sørensen, Signe Bek; Engelsby, Hanne; Gallego, Sandra F; Færgeman, Nils J.

    2015-01-01

    Long-chain fatty acyl-CoA esters are key intermediates in numerous lipid metabolic pathways, and recognized as important cellular signaling molecules. The intracellular flux and regulatory properties of acyl-CoA esters have been proposed to be coordinated by acyl-CoA-binding domain containing...... proteins (ACBDs). The ACBDs, which comprise a highly conserved multigene family of intracellular lipid-binding proteins, are found in all eukaryotes and ubiquitously expressed in all metazoan tissues, with distinct expression patterns for individual ACBDs. The ACBDs are involved in numerous intracellular...... processes including fatty acid-, glycerolipid- and glycerophospholipid biosynthesis, β-oxidation, cellular differentiation and proliferation as well as in the regulation of numerous enzyme activities. Little is known about the specific roles of the ACBDs in the regulation of these processes, however, recent...

  5. Determination of long-chain fatty acids in serum by gas chromatography coupled to mass spectrometry

    International Nuclear Information System (INIS)

    The quantification of long-chain fatty acids is fundamental for the diagnosis of several peroxisome disorders, particularly those in which the β-oxidation peroxisome of fatty acids is affected. In this work the implementation of an analytical method for the determination of these markers in serum by gas chromatography coupled to mass spectrometry is described. Besides, samples from patients with a diagnostic impression of adrenoleukodystrophy linked to the X chromosome were analyzed. The necessary experimental conditions were achieved for the separation and quantification of C22:0, C24:0 and C26:0 fatty acids in serum, which are biochemical markers of various peroxisome diseases. The application of this method allowed confirming the diagnosis of three patients with a diagnostic impression of adrenoleukodystrophy linked to the X chromosome. The application of the method in daily practice will allow the Cuban medical system to count on a new laboratory parameter for the diagnosis of peroxisome disorders

  6. Long-chain acyl-homoserine lactones from Methylobacterium mesophilicum: synthesis and absolute configuration.

    Science.gov (United States)

    Pomini, Armando M; Cruz, Pedro L R; Gai, Cláudia; Araújo, Welington L; Marsaioli, Anita J

    2009-12-01

    The acyl-homoserine lactones (acyl-HSLs) produced by Methylobacterium mesophilicum isolated from orange trees infected with the citrus variegated chlorosis (CVC) disease have been studied, revealing the occurrence of six long-chain acyl-HSLs, i.e., the saturated homologues (S)-N-dodecanoyl (1) and (S)-N-tetradecanoyl-HSL (5), the uncommon odd-chain N-tridecanoyl-HSL (3), the new natural product (S)-N-(2E)-dodecenoyl-HSL (2), and the rare unsaturated homologues (S)-N-(7Z)-tetradecenoyl (4) and (S)-N-(2E,7Z)-tetradecadienyl-HSL (6). The absolute configurations of all HSLs were determined as 3S. Compounds 2 and 6 were synthesized for the first time. Antimicrobial assays with synthetic acyl-HSLs against Gram-positive bacterial endophytes co-isolated with M. mesophilicum from CVC-infected trees revealed low or no antibacterial activity. PMID:19919062

  7. Synthesis of crystalline Cu2O nanoparticles using long chained alcohol

    International Nuclear Information System (INIS)

    The successful synthesis of highly crystallized cuprous oxide nanoparticles using long chained alcohol reduction method is reported. The purity of copper oxide obtained by this method greatly depends on the synthesis conditions such as reaction temperature, reaction duration, and hydroxyl ion concentration that assist the reduction kinetics. By optimizing the above parameters, cubic cuprous oxide with particle sizes controllable in the range of 10–30 nm were synthesized. The x-ray diffraction analysis confirmed the single-phased nature of Cu2O crystal. Furthermore, the ratio between copper and oxygen atoms in the product was determined to be 1.96 using the Rietveld analysis and confirmed the purity of Cu2O nanoparticles. In addition, I–V characteristics suggested that the nanoparticles function as semiconductor and indicated the use of these cuprous nanocrystals as a functional material for the preparation of solar devices. (papers)

  8. Regulation of lipolytic activity by long-chain acyl-coenzyme A in islets and adipocytes

    DEFF Research Database (Denmark)

    Hu, Liping; Deeney, Jude T; Nolan, Christopher J; Peyot, Marie-Line; Ao, Ada; Richard, Ann Marie; Luc, Esthere; Færgeman, Nils J.; Knudsen, Jens; Guo, Wen; Sorhede-Winzell, Maria; Prentki, Marc; Corkey, Barbara E

    2005-01-01

    -cells. The mechanisms by which lipolysis is regulated in different tissues is, therefore, of considerable interest. Here, the effects of long-chain acyl-CoA esters (LC-CoA) on lipase activity in islets and adipocytes were compared. Palmitoyl-CoA (Pal-CoA, 1-10 microM) stimulated lipase activity in islets...... adipocytes. The inhibitory effect of LC-CoA on adipocyte HSL was dependent on phosphorylation and enhanced by acyl-CoA-binding protein (ACBP). In contrast, the stimulatory effect on islet lipase activity was blocked by ACBP, presumably due to binding and sequestration of LC-CoA. These data suggest the...

  9. Strategies for recovering inhibition caused by long chain fatty acids on anaerobic thermophilic biogas reactors

    DEFF Research Database (Denmark)

    Palatsi, J.; Laureni, M.; Andres, M.V.;

    2009-01-01

    Long chain fatty acids (LCFA) concentrations over 1.0 g L1 were inhibiting manure thermophilic digestion, in batch and semi-continuous experiments, resulting in a temporary cease of the biogas production. The aim of the work was to test and evaluate several recovery actions, such as reactor feeding...... patterns, dilution and addition of adsorbents, in order to determine the most appropriate strategy for fast recovery of the reactor activity in manure based plants inhibited by LCFA. Dilution with active inoculum for increasing the biomass/LCFA ratio, or addition of adsorbents for adsorbing the LCFA...... and reducing the bioavailable LCFA concentration, were found to be the best recovery strategies, improving the recovery time from 10 to 2 days, in semi-continuously fed systems. Moreover, acclimatization was introduced by repeated inhibition and process recovery. The subsequent exposure of the anaerobic...

  10. Long-Chain Omega-3 Oils–An Update on Sustainable Sources

    Directory of Open Access Journals (Sweden)

    Peter D. Nichols

    2010-05-01

    Full Text Available Seafood is currently the best and generally a safe source of long-chain (LC, (≥C20 omega-3 oils amongst the common food groups. LC omega-3 oils are also obtained in lower amounts per serve from red meat, egg and selected other foods. As global population increases the opportunities to increase seafood harvest are limited, therefore new alternate sources are required. Emerging sources include microalgae and under-utilized resources such as Southern Ocean krill. Prospects for new land plant sources of these unique and health-benefiting oils are also particularly promising, offering hope for alternate and sustainable supplies of these key oils, with resulting health, social, economic and environmental benefits.

  11. A 5-month open study with long-chain polyunsaturated fatty acids in dyslexia.

    Science.gov (United States)

    Lindmark, Lars; Clough, Peter

    2007-12-01

    This open pilot study investigated effects of a docosahexaenoic acid (DHA)-rich supplement on learning ability in a group of 20 dyslexic children in Sweden. Children formally diagnosed as dyslexic took eight capsules per day of a long-chain polyunsaturated fatty acid (LC-PUFA) supplement containing high-DHA fish oil and evening primrose oil. Subjective assessments by the children and their parents were completed at baseline and 6, 12, and 20 weeks after supplementation. Quantitative evaluation by word-chain test was completed before and after 4 months of supplementation to measure word decoding (speed of reading) and letter decoding (motoric-perceptual speed). Subjective parent and child assessments showed increasing numbers of positive responders over time in reading speed, general schoolwork, and overall perceived benefit. Significant improvements were observed in reading speed and motor-perceptual velocity. Thirteen of 17 children had a significant improvement on the word-chain test (P dyslexia. PMID:18158838

  12. Purification of wet process phosphoric acid by solvent extraction with long-chain aliphatic amines

    International Nuclear Information System (INIS)

    Purification of phosphoric acid by solvent extraction with long-chain aliphatic amines is investigated. Extraction of cadmium is extensively examined regarding the importance of the aqueous phase, the diluent and the amine. The solubility of tri-n-octyl-amine is determined in water and phosphoric acid solutions. Properties of valuable constituent such as uranium and yttrium are screened. Modelling of the system is performed by adapting Bromley's model for electrolytes to the different dissociation/association equilibria in the aqueous phase. In the organic phase simple expressions are used for the non-ideal behaviour. Amine-acid equilibria are investigated for all acids present in industrial phosphoric acid. New extraction constants are calculated for phosphoric and hydro- fluosilic acid. Calculations are compared with experiments both from binary and multicomponent acid mixtures

  13. Oocyte production in Nellore cows supplemented with long-chain fatty acid soaps

    Directory of Open Access Journals (Sweden)

    Moacir Rogério de Souza

    2016-03-01

    Full Text Available ABSTRACT This study was conducted to evaluate the effects of long-chain fatty acid soaps (LCFAS of soybean oil on the production and quality of aspirated cumulus-oocyte complexes (COC of lactating Nellore (Bos taurus indicus cows. The effects of LCFAS on the plasma concentration of lipoproteins, total cholesterol, triacylglycerol, urea N, and insulin were also addressed. Thirty lactating Nellore cows were randomly assigned to one of two dietary groups. Cows were grazed on a Tifton 85 pasture throughout the experiment (100 days. Treatments consisted of a supplement with no fat included (CONT; and a supplement containing 47.2 g/kg of LCFAS on a dry matter basis. After 14 days of treatment, animals were subjected to 4.93±1.55 rounds of consecutive ovum pickup (OPU at intervals of 21.71±11.76 days. Blood samples were collected from all cows throughout the experiment at 25-day intervals (four samples per cow. Cows that were fed LCFAS supplements and cows that were fed CONT supplements had similar numbers of total aspirated oocytes (viable and not viable by OPU and grades of viable oocytes. Plasma concentrations of high-density lipoprotein (HDL were increased in cows supplemented with LCFAS. Plasma concentrations of LDL and total cholesterol were increased by LCFAS supplementation after 50 days on dietary treatment and insulin concentration was increased from 75 days on treatment. Long-chain fatty acid soaps from soybean oil added at 47.2 g/kg have no effect on the number of aspirated COC or their quality in Nellore lactating cows even with changes in plasma concentration of HDL, LDL, total cholesterol, and insulin. Thus, this supplementation has no benefits when the main objective is to improve oocyte production and quality.

  14. Very long-chain fatty acids support synaptic structure and function in the mammalian retina

    Directory of Open Access Journals (Sweden)

    Hopiavuori Blake R.

    2016-01-01

    Full Text Available Elongation of Very Long chain fatty acids-like 4 (ELOVL4 is a fatty acid elongase responsible for the biosynthesis of very long chain (VLC; ≥ C26 fatty acids in the retina, brain, skin, Meibomian gland, and testes. Heterozygous inheritance of mutant ELOVL4 causes juvenile macular degeneration in autosomal dominant Stargardt-like macular dystrophy (STGD3. Retinal photoreceptors are enriched with VLC polyunsaturated fatty acids (VLC-PUFAs, which have been shown by our group and others to be necessary for the survival of rod photoreceptors. Our group performed a series of studies using mice conditionally depleted of retinal Elovl4 (KO aimed at understanding the role of VLC-PUFAs in long-term retinal health and function, focusing on the role of these fatty acids in mediating synaptic function between the photoreceptors and the rest of the neural retina. The absence of VLC-PUFA from the retina of KO mice resulted in a marked decrease in retinal b-wave responses of the electroretinogram as well as a decrease in the amplitude of the oscillatory potentials mediated by the neural retina. Although there were no measureable differences between KO and wild type (WT mice in either pre-synaptic rod calcium channel function or post-synaptic bipolar cell glutamate receptor responses, ultrastructural analysis revealed a marked decrease in the diameter of synaptic vesicles in rod terminals. Recent quantification suggests that this decrease in synaptic vesicle size due to the absence of VLC-PUFAs in KO mice, and the consequent decrease in glutamate content, could account for the decrease in b-wave response amplitudes that were previously measured in these animals.

  15. Two novel COLVI long chains in zebrafish that are essential for muscle development.

    Science.gov (United States)

    Ramanoudjame, Laetitia; Rocancourt, Claire; Lainé, Jeanne; Klein, Arnaud; Joassard, Lucette; Gartioux, Corine; Fleury, Marjory; Lyphout, Laura; Kabashi, Edor; Ciura, Sorana; Cousin, Xavier; Allamand, Valérie

    2015-12-01

    Collagen VI (COLVI), a protein ubiquitously expressed in connective tissues, is crucial for structural integrity, cellular adhesion, migration and survival. Six different genes are recognized in mammalians, encoding six COLVI-chains that assemble as two 'short' (α1, α2) and one 'long' chain (theoretically any one of α3-6). In humans, defects in the most widely expressed heterotrimer (α123), due to mutations in the COL6A1-3 genes, cause a heterogeneous group of neuromuscular disorders, collectively termed COLVI-related muscle disorders. Little is known about the function(s) of the recently described α4-6 chains and no mutations have been detected yet. In this study, we characterized two novel COLVI long chains in zebrafish that are most homologous to the mammalian α4 chain; therefore, we named the corresponding genes col6a4a and col6a4b. These orthologues represent ancestors of the mammalian Col6a4-6 genes. By in situ hybridization and RT-qPCR, we unveiled a distinctive expression kinetics for col6a4b, compared with the other col6a genes. Using morpholino antisense oligonucleotides targeting col6a4a, col6a4b and col6a2, we modelled partial and complete COLVI deficiency, respectively. All morphant embryos presented altered muscle structure and impaired motility. While apoptosis was not drastically increased, autophagy induction was defective in all morphants. Furthermore, motoneuron axon growth was abnormal in these morphants. Importantly, some phenotypical differences emerged between col6a4a and col6a4b morphants, suggesting only partial functional redundancy. Overall, our results further confirm the importance of COLVI in zebrafish muscle development and may provide important clues for potential human phenotypes associated with deficiency of the recently described COLVI-chains. PMID:26362255

  16. Long-chain alkenones and related compounds in the benthic haptophyte Chrysotila lamellosa Anand HAP 17.

    Science.gov (United States)

    Rontani, Jean-François; Beker, Béatriz; Volkman, John K

    2004-01-01

    The neutral lipid compositions of the coastal haptophyte Chrysotila lamellosa HAP 17 grown in batch culture at 10 and 20 degrees C have been determined. A comparison was also made between the lipid compositions of cells harvested in early and late stationary phase. This species contains a suite of very long-chain C(37)-C(40) alkenones and alkenoates as found in a few microalgae from the Haptophyta. The distributions of these compounds show some differences to earlier reports of different strains of this alga, which are only in part attributable to culture conditions. A suite of long-chain alkenols, the reduced form of the alkenones, was characterized for the first time. The abundance of these compounds was only 1.5% of that of the corresponding alkenones, and the relative proportion of C(37)-C(38) constituents depended on growth temperature. These data show that haptophyte algae are a possible source of the alkenols found in some marine sediments, but the small amounts found suggest that other sources such as bacterial reduction of alkenones are more likely in highly reducing sediments. A mixture of C(29)-C(33) n-alkenes, dominated by the C(31:1) monoene, was found in marked contrast to previous analyses of other strains which reported only the presence of a C(31:2) diene. The sterol distribution included the common haptophyte sterol 24alpha-methylcholesta-5,22E-dien-3beta-ol (epi-brassicasterol) as well as significant amounts of Delta(5)- and Delta(5,22)-C(29) sterols. PMID:14697277

  17. Development of thermorewritable marking media composed of polymeric films with dispersed long chain molecules

    International Nuclear Information System (INIS)

    Materials used as reversible recording media are now attracting attention from environmental as well as technological viewpoints, because they would save plastic products such as the cards and sheets used for an overhead projector, and by offering superior functionality, they would find new markets. A thermoreversible recording medium composed of a polymer matrix with a dispersed long chain molecule may be promising for practical use, because the two optically different states (transparent and light-scattering states) can be selected using only temperature; control of the cooling or heating rate is not necessary. However, the medium has the problem that the image contrast decreases as the number of repetitions of image formation using a thermal printing head and deletion using a hot stamp increases. In order to clarify the deterioration mechanism of the image contrast and the influence of the polymer property on the deterioration, we have carried out the inside structure analysis using a TEM. In result, it was clarified that the deterioration was caused by a cohesion and an expansion of particles of the long chain molecule by a heating and a shear stress of the thermal printing head. Furthermore, we have studied the improvement of the deterioration by a cross-link of the polymer in the medium by EB radiation. The image contrast of the medium could be maintained by the cross-link of the polymer even when the image formation and deletion were repeated 1000 times, because the temperature range of a rubbery state of the polymer was widened to a temperature higher than 200degC from around 100degC, and the cohesion and the expansion of the particles did not occur. (author)

  18. Biodiscovery of new Australian thraustochytrids for production of biodiesel and long-chain omega-3 oils

    Energy Technology Data Exchange (ETDEWEB)

    Lee Chang, Kim Jye [CSIRO, Hobart, TAS (Australia). Energy Transformed National Research Flagship; CSIRO Marine and Atmospheric Research, Hobart, TAS (Australia); Tasmania Univ., Hobart, TAS (Australia). School of Plant Science; Dunstan, Graeme A.; Blackburn, Susan I. [CSIRO, Hobart, TAS (Australia). Energy Transformed National Research Flagship; CSIRO Marine and Atmospheric Research, Hobart, TAS (Australia); Abell, Guy C.J.; Clementson, Lesley A. [CSIRO Marine and Atmospheric Research, Hobart, TAS (Australia); Nichols, Peter D. [CSIRO, Hobart, TAS (Australia). Food Futures National Research Flagship; CSIRO Marine and Atmospheric Research, Hobart, TAS (Australia); Koutoulis, Anthony [Tasmania Univ., Hobart, TAS (Australia). School of Plant Science

    2012-03-15

    Heterotrophic growth of thraustochytrids has potential in co-producing a feedstock for biodiesel and long-chain (LC, {>=}C{sub 20}) omega-3 oils. Biodiscovery of thraustochytrids from Tasmania (temperate) and Queensland (tropical), Australia, covered a biogeographic range of habitats including fresh, brackish, and marine waters. A total of 36 thraustochytrid strains were isolated and separated into eight chemotaxonomic groups (A-H) based on fatty acid (FA) and sterol composition which clustered closely with four different genera obtained by 18S rDNA molecular identification. Differences in the relative proportions (%FA) of long-chain C{sub 20}, C{sub 22}, omega-3, and omega-6 polyunsaturated fatty acids (PUFA), including docosahexaenoic acid (DHA), docosapentaenoic acid, arachidonic acid, eicosapentaenoic acid (EPA), and saturated FA, as well as the presence of odd-chain PUFA (OC-PUFA) were the major factors influencing the separation of these groups. OC-PUFA were detected in temperate strains of groups A, B, and C (Schizochytrium and Thraustochytrium). Group D (Ulkenia) had high omega-3 LC-PUFA (53% total fatty acids (TFA)) and EPA up to 11.2% TFA. Strains from groups E and F (Aurantiochytrium) contained DHA levels of 50-61% TFA after 7 days of growth in basal medium at 20 C. Groups G and H (Aurantiochytrium) strains had high levels of 15:0 (20-30% TFA) and the sum of saturated FA was in the range of 32-51%. {beta},{beta}-Carotene, canthaxanthin, and astaxanthin were identified in selected strains. Phylogenetic and chemotaxonomic groupings demonstrated similar patterns for the majority of strains. Our results demonstrate the potential of these new Australian thraustochytrids for the production of biodiesel in addition to omega-3 LC-PUFA-rich oils. (orig.)

  19. Highly enantio- and diastereoselective allylic alkylation of Morita-Baylis-Hillman carbonates with allyl ketones

    KAUST Repository

    Tong, Guanghu

    2013-05-17

    The asymmetric allylic alkylation of Morita-Baylis-Hillman (MBH) carbonates with allyl ketones has been developed. The α-regioselective alkylation adducts, containing a hexa-1,5-diene framework with important synthetic value, were achieved in up to 83% yield, >99% ee, and 50:1 dr by using a commercially available Cinchona alkaloid as the catalyst. From the allylic alkylation adduct, a cyclohexene bearing two adjacent chiral centers was readily prepared. © 2013 American Chemical Society.

  20. Long chain n-alkanes and their carbon isotopes in lichen species from western Hubei Province: implication for geological records

    Institute of Scientific and Technical Information of China (English)

    Xianyu HUANG; Jiantao XUE; Shouyu GUO

    2012-01-01

    Five coticolous lichen samples were collected from western Hubei Province of China to analyze the long chain n-alkanes and their carbon isotope compositions.The n-alkanes range in carbon number from C17 to C33 with strong odd-over-even predominance between C21and C33.Lichens are dominated by n-C29 in the samples of Dajiuhu,Shennongjia Mountain,but by both n-C23 and n-C29 at Qizimei Mountain.This difference may result from the different environmental conditions in these two sites.The δ13C values of long chain n-alkanes in lichen samples show the signature of C3 plants.Based on compoundspecific carbon isotopic values and previous results,we state that alkane homologs > C23 mainly originate from the symbiotic fungi,while symbiotic algae only contribute trace amount of long chain alkanes.Of great interesting is the occurrence of long chain 3-methylalkanes in the Qizimei samples.These anteiso compounds range from C24 to C32,displaying obvious even-over-odd predominance.This study reveals that the association of long chain 3-methylalkanes with n-C23 alkane might be used as proxies to reconstruct the paleoecological implications of lichens in Earth history.

  1. Dietary a-linolenic acid, linoleic acid, and n-3 long-chain PUFA and risk of ischemic heart disease

    DEFF Research Database (Denmark)

    Vedtofte, Mia Sadowa; Jakobsen, Marianne Uhre; Lauritzen, Lotte;

    2011-01-01

    n-3 (omega-3) PUFA has been proposed as having health-promoting effects, primarily in relation to ischemic heart disease (IHD). Whether these benefits can be achieved by both α-linolenic acid (ALA, 18:3n-3) and n-3 long-chain PUFA (LC-PUFA) is debatable.......n-3 (omega-3) PUFA has been proposed as having health-promoting effects, primarily in relation to ischemic heart disease (IHD). Whether these benefits can be achieved by both α-linolenic acid (ALA, 18:3n-3) and n-3 long-chain PUFA (LC-PUFA) is debatable....

  2. Microscale and nanoscale hierarchical structured mesh films with superhydrophobic and superoleophilic properties induced by long-chain fatty acids

    Science.gov (United States)

    Wang, Shutao; Song, Yanlin; Jiang, Lei

    2007-01-01

    Inspired by the lotus effect, we fabricate new microscale and nanoscale hierarchical structured copper mesh films by a simple electrochemical deposition. After modification of the long-chain fatty acid monolayer, these films show superhydrophobic and superoleophilic properties, which could be used for the effective separation of oil and water. The length of the fatty acid chain strongly influences the surface wettability of as-prepared films. It is confirmed that the cooperative effect of the hierarchical structure of the copper film and the nature of the long-chain fatty acid contribute to this unique surface wettability.

  3. Microscale and nanoscale hierarchical structured mesh films with superhydrophobic and superoleophilic properties induced by long-chain fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Wang Shutao [Center for Molecular Science, Institute of Chemistry, Beijing 100080 (China); Song Yanlin [Center for Molecular Science, Institute of Chemistry, Beijing 100080 (China); Jiang Lei [Center for Molecular Science, Institute of Chemistry, Beijing 100080 (China)

    2007-01-10

    Inspired by the lotus effect, we fabricate new microscale and nanoscale hierarchical structured copper mesh films by a simple electrochemical deposition. After modification of the long-chain fatty acid monolayer, these films show superhydrophobic and superoleophilic properties, which could be used for the effective separation of oil and water. The length of the fatty acid chain strongly influences the surface wettability of as-prepared films. It is confirmed that the cooperative effect of the hierarchical structure of the copper film and the nature of the long-chain fatty acid contribute to this unique surface wettability.

  4. Microscale and nanoscale hierarchical structured mesh films with superhydrophobic and superoleophilic properties induced by long-chain fatty acids

    International Nuclear Information System (INIS)

    Inspired by the lotus effect, we fabricate new microscale and nanoscale hierarchical structured copper mesh films by a simple electrochemical deposition. After modification of the long-chain fatty acid monolayer, these films show superhydrophobic and superoleophilic properties, which could be used for the effective separation of oil and water. The length of the fatty acid chain strongly influences the surface wettability of as-prepared films. It is confirmed that the cooperative effect of the hierarchical structure of the copper film and the nature of the long-chain fatty acid contribute to this unique surface wettability

  5. Identify alkylation hazards

    International Nuclear Information System (INIS)

    This paper reports that extensive experience shows that alkylation plants regardless of acid catalyst choice, can be operated safely, and with minimum process risk to employees or neighbors. Both types of plants require a comprehensive and fully supported hazard management program that accounts for differing physical properties of the acids involved. Control and mitigation cost to refiners will vary considerably from plant to plant and location to location. In the author's experience, the order of magnitude costs will be about $1 to $2 million for a sulfuric acid (SA) alkylation plant, and about $10 to $15 million for a hydrofluoric acid (HF) plant. These costs include water supply systems and impoundment facilities for contaminated runoff water. The alkylation process, which chemically reacts isobutane and light olefins in the presence of a strong acid catalyst into a premium gasoline component is described

  6. The Staphylococcus aureus response to unsaturated long chain free fatty acids: survival mechanisms and virulence implications.

    Directory of Open Access Journals (Sweden)

    John G Kenny

    Full Text Available Staphylococcus aureus is an important human commensal and opportunistic pathogen responsible for a wide range of infections. Long chain unsaturated free fatty acids represent a barrier to colonisation and infection by S. aureus and act as an antimicrobial component of the innate immune system where they are found on epithelial surfaces and in abscesses. Despite many contradictory reports, the precise anti-staphylococcal mode of action of free fatty acids remains undetermined. In this study, transcriptional (microarrays and qRT-PCR and translational (proteomics analyses were applied to ascertain the response of S. aureus to a range of free fatty acids. An increase in expression of the sigma(B and CtsR stress response regulons was observed. This included increased expression of genes associated with staphyloxanthin synthesis, which has been linked to membrane stabilisation. Similarly, up-regulation of genes involved in capsule formation was recorded as were significant changes in the expression of genes associated with peptidoglycan synthesis and regulation. Overall, alterations were recorded predominantly in pathways involved in cellular energetics. In addition, sensitivity to linoleic acid of a range of defined (sigB, arcA, sasF, sarA, agr, crtM and transposon-derived mutants (vraE, SAR2632 was determined. Taken together, these data indicate a common mode of action for long chain unsaturated fatty acids that involves disruption of the cell membrane, leading to interference with energy production within the bacterial cell. Contrary to data reported for other strains, the clinically important EMRSA-16 strain MRSA252 used in this study showed an increase in expression of the important virulence regulator RNAIII following all of the treatment conditions tested. An adaptive response by S. aureus of reducing cell surface hydrophobicity was also observed. Two fatty acid sensitive mutants created during this study were also shown to diplay altered

  7. Critical constants and acentric factors for long-chain alkanes suitable for corresponding states applications

    DEFF Research Database (Denmark)

    Kontogeorgis, Georgios; Dimitrios, Tassios

    1997-01-01

    Several methods for the estimation of the critical temperature T-c, the critical pressure P-c, and the acentric factor omega for long-chain n-alkanes are reviewed and evaluated for the prediction of vapor pressures using Corresponding States (CS) methods, like the Lee-Kesler equation and the cubic...... equations of state. Most reliable and recent literature methods proposed for the estimation of the acentric factor of heavy alkanes yield similar values and the emphasis is, thus, given to the determination of the best sets of T-c and P-c. Various extrapolation schemes proposed for this purpose and several...... general group-contribution methods were investigated in this work. The correlations proposed by K. Magoulas and D. Tassios, Thermophysical properties of n-alkanes from C-1 to C-20 and their prediction for higher ones, Fluid Phase Equilibria, 56 ( 1990) 119-140; A.S. Teja, R.J. Lee, D.J. Rosenthal, M...

  8. Opportunities to enhance alternative sources of long-chain n-3 fatty acids within the diet.

    Science.gov (United States)

    Delarue, Jacques; Guriec, Nathalie

    2014-08-01

    Health benefits or advocated health benefits of long-chain (LC) n-3 PUFA are better known by medical doctors as well as by consumers, so that consumption increases. In addition, the development of aquaculture requires more fishmeal and fish oil. Humanisation of care of companion animals is also associated with addition of LC n-3 PUFA in pet foods. The risk of the increased demand for LC n-3 PUFA is the excess harvesting of natural sources, especially of marine origin (oily fishes, krill). In order to improve sustainability, alternative sources of LC n-3 PUFA have been developed. These alternative sources are: (a) terrestrial plants naturally or genetically enriched in stearidonic acid (SDA), which bypasses the first limiting step of (i.e. ∆6 desaturase) of the biosynthesis of LC n-3 PUFA; (b) single-cell oils rich in LC n-3 PUFA (microalgae, Escherichia coli) and krill. Currently, plants rich in SDA are expensive, metabolic engineering is unfavourably accepted by consumers in many countries, cultivation of microalgae is very expensive even though their ability (for some of them) to synthesise biofuels could induce a decrease in industrial costs, and Antarctic krill harvest must be restricted. Thus, it is difficult to predict their real development in the future. PMID:24886839

  9. Long chain lipid based tamoxifen NLC. Part I: preformulation studies, formulation development and physicochemical characterization.

    Science.gov (United States)

    Shete, Harshad; Patravale, Vandana

    2013-09-15

    Tamoxifen citrate (Tmx) was formulated in nanostructured lipid carrier system (NLC) using long chain solid lipids (LCSL) and oils (LCO) with the aim to target lymphatic system to improve its bioavailability in plasma and lymphnode (initial sites for metastasis) and reduce its drug associated toxicity. Tamoxifen loaded NLC (Tmx-NLC) was formulated using solvent diffusion technique. Preformulation studies comprised evaluation of drug-excipients compatibility. Solubility of Tmx was screened in LCSL and LCO, surfactants and co-surfactants to identify NLC components. Surfactant co-surfactant combinations were studied for their ability to stabilize the system. Tmx-NLC was physicochemically characterized by TEM, DSC, XRD, and FTIR studies. Drug-excipients chemical compatibility study facilitated anticipation of excipients induced oxidative degradation of Tmx. Suitable storage condition below 30°C could stabilize Tmx. Tmx-NLC with >90% entrapment efficiency and 215.60 ± 7.98 nm particle size were prepared and freeze dried. Freeze dried Tmx-NLC could withstand various gastrointestinal tract (GI) media (pH 1.2, pH 3.5, pH 4.5, pH 6.8, pH 7.4). Dissolution profile of Tmx-NLC in various media showed sustained release pattern irrespective of pH of medium. No significant change in characteristics of Tmx-NLC was observed after 3 months of accelerated stability studies. PMID:23535345

  10. Role of Dietary Long-Chain Polyunsaturated Fatty Acids in Infant Allergies and Respiratory Diseases

    Directory of Open Access Journals (Sweden)

    Lynette P. Shek

    2012-01-01

    Full Text Available Maternal nutrition has critical effects on the developing structures and functions of the fetus. Malnutrition during pregnancy can result in low birth weight and small for gestational age babies, increase risk for infection, and impact the immune system. Long-chain polyunsaturated fatty acids (PUFAs have been reported to have immunomodulatory effects. Decreased consumption of omega-6 PUFAs, in favor of more anti-inflammatory omega-3 PUFAs in modern diets, has demonstrated the potential protective role of omega-3 PUFAs in allergic and respiratory diseases. In this paper, we examine the role of PUFAs consumption during pregnancy and early childhood and its influence on allergy and respiratory diseases. PUFAs act via several mechanisms to modulate immune function. Omega-3 PUFAs may alter the T helper (Th cell balance by inhibiting cytokine production which in turn inhibits immunoglobulin E synthesis and Th type 2 cell differentiation. PUFAs may further modify cellular membrane, induce eicosanoid metabolism, and alter gene expression. These studies indicate the benefits of omega-3 PUFAs supplementation. Nevertheless, further investigations are warranted to assess the long-term effects of omega-3 PUFAs in preventing other immune-mediated diseases, as well as its effects on the later immunodefense and health status during early growth and development.

  11. Toxicity of long chain fatty acids towards acetate conversion by Methanosaeta concilii and Methanosarcina mazei.

    Science.gov (United States)

    Silva, Sérgio A; Salvador, Andreia F; Cavaleiro, Ana J; Pereira, M Alcina; Stams, Alfons J M; Alves, M Madalena; Sousa, Diana Z

    2016-07-01

    Long-chain fatty acids (LCFA) can inhibit methane production by methanogenic archaea. The effect of oleate and palmitate on pure cultures of Methanosaeta concilii and Methanosarcina mazei was assessed by comparing methane production rates from acetate before and after LCFA addition. For both methanogens, a sharp decrease in methane production (> 50%) was observed at 0.5 mmol L(-1) oleate, and no methane was formed at concentrations higher than 2 mmol L(-1) oleate. Palmitate was less inhibitory than oleate, and M. concilii was more tolerant to palmitate than M. mazei, with 2 mmol L(-1) palmitate causing 11% and 64% methanogenic inhibition respectively. This study indicates that M. concilii and M. mazei tolerate LCFA concentrations similar to those previously described for hydrogenotrophic methanogens. In particular, the robustness of M. concilii might contribute to the observed prevalence of Methanosaeta species in anaerobic bioreactors used to treat LCFA-rich wastewater. PMID:27273786

  12. Aminocarnitine and acylaminocarnitines: Carnitine acyltransferase inhibitors affecting long-chain fatty acid and glucose metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Clark, D.J.

    1989-01-01

    DL-Aminocarnitine (DL-3-amino-4-trimethylaminobutyrate) and the acylaminocarnitines acetyl-, decanoyl- and palmitoyl-DL-aminocarnitine have been synthesized and tested as inhibitors of carnitine palmitoyl-transferase and carnitine acetyltransferase in vitro and in vivo. Acetyl-DL-aaminocarnitine is the most potent reversible inhibitor of carnitine acetyltransferase reported to date, and is competitive with respect to acetyl-L-carnitine. Mice given acetyl-DL-aminocarnitine metabolize (U-{sup 14}C)acetyl-L-carnitine at about 60% of the rate of control mice. Palmitoyl-DL-aminocarnitine is the most potent reversible inhibitor of carnitine palmitoyltransferase reported to date. Decanoyl-DL-aminocarnitine and DL-aminocarnitine are also very potent inhibitors; all compounds inhibit the catabolism of ({sup 14}C)palmitate to {sup 14}CO{sub 2} in intact mice by at least 50%. Carnitine palmitoyltransferase controls the entry of long-chain fatty acids into the mitochondrial matrix for {beta}-oxidation. The inhibition of carnitine palmitoyltransferase by aminocarnitine or acylaminocarnitines in vivo prevents or reverses ketogenesis in fasted mice, and causes the reversible accumulation of triglycerides in liver, kidney and plasma. Administration of DL-aminocarnitine to streptozotocindiabetic mice lowers plasma glucose levels and improves the glucose tolerance test.

  13. pH-Tunable wormlike micelles based on an ultra-long-chain "pseudo" gemini surfactant.

    Science.gov (United States)

    Feng, Yujun; Chu, Zonglin

    2015-06-21

    Smart surfactant wormlike micelles (SWLMs), responsive to external stimuli, are a particularly recent area of development, yet highly promising, given the versatility of the materials but simplicity of the design. Here, we developed a pH-switchable wormlike micellar system based on a "pseudo" gemini surfactant (named as EAMA) formed by a mixture of N-erucamido-N,N-dimethylamine (UC22AMPM) and maleic acid with a molar ratio of 2 : 1, and compared the "pseudo" gemini worm system with UC22AMPM in the presence of hydrochloric acid (EAHCl). It was found that both maleic acid and hydrochloric acid can protonate the ultra-long-chain tertiary amine into a quaternary ammonium surfactant, thereby forming wormlike micelles; however, much stronger viscoelastic behavior was evidenced in the maleic acid system because one protonated maleic acid molecule can "bridge" two quaternized UC22AMPM molecules via electrostatic attraction. In contrast, the EAHCl system just shows a "mono" quaternary ammonium feature with a weak viscosity buildup. In addition, the maleic acid-based worm system was found to be more thermo-sensitive than conventional wormlike micelles, which also originates due to its "pseudo" gemini architecture. PMID:25959441

  14. Quantitative characterization of short- and long-chain perfluorinated acids in solid matrices in Shanghai, China

    International Nuclear Information System (INIS)

    Perfluorinated acids (PFAs) have been recognized as emerging environmental pollutants because of their widespread occurrences, persistence, and bioaccumulative and toxicological effects. PFAs have been detected in aquatic environment and biota in China, but the occurrences of these chemicals have not been reported in solid matrices in China. In the present study, short- and long-chain PFAs (C2-C14) have been quantitatively determined in solid matrices including sediments, soils and sludge collected in Shanghai, China. The results indicate that sludge contains more PFAs than sediments and soils, and the total PFAs concentrations in sediments, soil and sludge are 62.5-276 ng g-1, 141-237 ng g-1 and 413-755 ng g-1, respectively. In most cases, trifluoroacetic acid was the major PFA and accounted for 22-90% of the total PFAs. Although the levels of perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) were not only lower than trifluoroacetic acid, but also lower than some short-chain PFCAs (< C8) in some individual cases, PFOA and PFOS were still the major pollution compounds in most cases and they constituted 2-34% and 1-9% of the total PFAs, respectively. Meanwhile, unlike previous studies, PFOS levels were not always higher than PFOA in solids collected in Shanghai, China. Given that some short-chain PFAs such as trifluoroacetic acid are mildly phytotoxic and their higher levels in solid matrices were collected in Shanghai, China, these chemicals should be included in future environmental monitoring efforts.

  15. Long Chain Molecules in the Molten State: Surface Adsorption, Near Surface Structure, and Mutual-Diffusion

    Science.gov (United States)

    Zhao, Xiaofeng

    1993-01-01

    The surface segregation in a binary mixture of polymer due to surface energy difference or end-grafting is studied. The surface energy difference induced segregation is compared with the mean-field theory. The end-labeling of chains strengthens the ability of the chain to bind to the surface, and the stretching of the end grafted chains is proved to be a controlling fact limiting the brush density. The structure of a chain near a surface needs to be known in order to make more quantitative analysis. Such knowledge is currently not available although a reflecting surface model is proposed. We also studied the mutual-diffusion of compatible linear chains. It is observed that the broadening of the interfacial width scales as the 1/4 power of the diffusion time for a time scale much longer than the reptation time. It is speculated that the anomalous behavior is either due to small molecular residue in the sample or due to the long chain nature of the polymer itself. If the former possibility can be ruled out, the validity of applying the reptation model to polymer diffusion over small distances might be under challenge. Dynamic secondary ion mass spectrometry (SIMS) is an established technique and its application in polymer science has been around for quite some time. However, the quantitative application in depth profiling was so far not very successful. The technique is reviewed and procedures that ensure correct extraction of depth profiles from raw SIMS data are discussed.

  16. Aminocarnitine and acylaminocarnitines: Carnitine acyltransferase inhibitors affecting long-chain fatty acid and glucose metabolism

    International Nuclear Information System (INIS)

    DL-Aminocarnitine (DL-3-amino-4-trimethylaminobutyrate) and the acylaminocarnitines acetyl-, decanoyl- and palmitoyl-DL-aminocarnitine have been synthesized and tested as inhibitors of carnitine palmitoyl-transferase and carnitine acetyltransferase in vitro and in vivo. Acetyl-DL-aaminocarnitine is the most potent reversible inhibitor of carnitine acetyltransferase reported to date, and is competitive with respect to acetyl-L-carnitine. Mice given acetyl-DL-aminocarnitine metabolize [U-14C]acetyl-L-carnitine at about 60% of the rate of control mice. Palmitoyl-DL-aminocarnitine is the most potent reversible inhibitor of carnitine palmitoyltransferase reported to date. Decanoyl-DL-aminocarnitine and DL-aminocarnitine are also very potent inhibitors; all compounds inhibit the catabolism of [14C]palmitate to 14CO2 in intact mice by at least 50%. Carnitine palmitoyltransferase controls the entry of long-chain fatty acids into the mitochondrial matrix for β-oxidation. The inhibition of carnitine palmitoyltransferase by aminocarnitine or acylaminocarnitines in vivo prevents or reverses ketogenesis in fasted mice, and causes the reversible accumulation of triglycerides in liver, kidney and plasma. Administration of DL-aminocarnitine to streptozotocindiabetic mice lowers plasma glucose levels and improves the glucose tolerance test

  17. Controlled formation of ag nanoparticles by means of long-chain sodium polyacrylates in dilute solution.

    Science.gov (United States)

    Huber, Klaus; Witte, Thomas; Hollmann, Jutta; Keuker-Baumann, Susanne

    2007-02-01

    A new tool is presented to control formation of Ag nanoparticles. Small amounts of silver ions were added to dilute solutions of long-chain sodium polyacrylates (NaPA). Four NaPA samples covering a molar mass regime of 97 kD polyacrylate coils toward compact structures. Coil shrinking and aggregation was revealed by means of time-resolved static light scattering. If exposed to UV-radiation, small Ag particles formed within the shrunken anionic polyacrylate coils. The Ag nanoparticles were identified by means of an enhanced light scattering and a characteristic plasmon absorption band around 410 nm. No such Ag particle formation could be observed even at 5 times larger concentrations of Ag(+) and NaPA if the two smallest polyacrylate samples have been used under otherwise equal conditions. This molar mass sensitive response of NaPA to Ag(+)-addition suggests an interesting phenomenon: if the coil size of the NaPa chains, which act as Ag(+) collectors, is large enough, local Ag(+) concentration in these coil-shaped Ag(+) containers exceeds a critical value, and irradiation with UV generates Ag nanoparticles. PMID:17263389

  18. Effects of Long Chain Fatty Acid Synthesis and Associated Gene Expression in Microalga Tetraselmis sp.

    Directory of Open Access Journals (Sweden)

    T. Catalina Adarme-Vega

    2014-06-01

    Full Text Available With the depletion of global fish stocks, caused by high demand and effective fishing techniques, alternative sources for long chain omega-3 fatty acids are required for human nutrition and aquaculture feeds. Recent research has focused on land-based cultivation of microalgae, the primary producers of omega-3 fatty acids in the marine food web. The effect of salinity on fatty acids and related gene expression was studied in the model marine microalga, Tetraselmis sp. M8. Correlations were found for specific fatty acid biosynthesis and gene expression according to salinity and the growth phase. Low salinity was found to increase the conversion of C18:4 stearidonic acid (SDA to C20:4 eicosatetraenoic acid (ETA, correlating with increased transcript abundance of the Δ-6-elongase-encoding gene in salinities of 5 and 10 ppt compared to higher salinity levels. The expression of the gene encoding β-ketoacyl-coenzyme was also found to increase at lower salinities during the nutrient deprivation phase (Day 4, but decreased with further nutrient stress. Nutrient deprivation also triggered fatty acids synthesis at all salinities, and C20:5 eicosapentaenoic acid (EPA increased relative to total fatty acids, with nutrient starvation achieving a maximum of 7% EPA at Day 6 at a salinity of 40 ppt.

  19. Reversible Self-Assembly of Backbone-Thermoresponsive Long Chain Hyperbranched Poly(N-Isopropyl Acrylamide

    Directory of Open Access Journals (Sweden)

    Ting-Ting Liu

    2016-01-01

    Full Text Available In this paper, we mainly described the reversible self-assembly of a backbone-thermoresponsive, long-chain, hyperbranched poly(N-isopropyl acrylamide (LCHBPNIPAM in aqueous solution. Here, we revealed a reversible self-assembly behavior of LCHBPNIPAM aqueous solution derived from temperature. By controlling the temperature of LCHBPNIPAM aqueous solution, we tune the morphology of the LCHBPNIPAM self-assemblies. When the solution temperature increased from the room temperature to the lower critical solution temperature of PNIPAM segments, LCHBPNIPAM self-assembled from multi-compartment vesicles into solid micelles. The morphology of LCHBPNIPAM self-assemblies changed from solid micelles to multi-compartment vesicles again when the temperature decreased back to the room temperature. The size presented, at first, an increase, and then a decrease, tendency in the heating-cooling process. The above thermally-triggered self-assembly behavior of LCHBPNIPAM aqueous solution was investigated by dynamic/static light scattering, transmission electron microscopy, atomic force microscopy, fluorescence spectroscopy, 1H nuclear magnetic resonance in D2O, and attenuated total reflectance Fourier transform infrared spectroscopy. These results indicated that LCHBPNIPAM aqueous solution presents a reversible self-assembly process. The controlled release behaviors of doxorubicin from the vesicles and micelles formed by LCHBPNIPAM further proved the feasibility of these self-assemblies as the stimulus-responsive drug delivery system.

  20. Radiation induced solid-state polymerization of long-chain acrylates containing fluorocarbon chain

    International Nuclear Information System (INIS)

    γ-Ray irradiation post-polymerizations of long-chain acrylates containing fluorocarbon chain, H(CF2)10CH2OCOCH=CH2 and H(CF2)8CH2OCOCH=CH2, were investigated and also the structures and thermal properties of comb-like polymers obtained were studied. It was found that these monomers exhibited very high polymerizability at wide temperature ranges around the melting points. Because the fluorocarbon chains are less flexible and thicker than the hydrocarbon chains, it can be expected that the aggregation force among the monomer molecules is strong and the conformational freedom of functional group for polymerization is large. According to the DSC and the X-ray diffraction measurements of the comb-like polymers obtained, the fluorocarbon chains are aggregated in a mode of hexagonal packing in the lamellar crystals. This situation can be considered as an optimum condition for the γ-ray irradiation post-polymerization. (author)

  1. Dynamic functional characterization and phylogenetic changes due to Long Chain Fatty Acids pulses in biogas reactors.

    Science.gov (United States)

    Kougias, Panagiotis G; Treu, Laura; Campanaro, Stefano; Zhu, Xinyu; Angelidaki, Irini

    2016-01-01

    The process stability of biogas plants is often deteriorated by the accumulation of Long Chain Fatty Acids (LCFA). The microbial community shifts due to LCFA disturbances have been poorly understood as the molecular techniques used were not able to identify the genome characteristics of uncultured microorganisms, and additionally, the presence of limited number of reference genomes in public databases prevented the comprehension of specific functional roles characterizing these microorganisms. The present study is the first research which deciphers by means of high throughput shotgun sequencing the dynamics of the microbial community during an inhibitory shock load induced by single pulses of unsaturated LCFA at two different concentrations (i.e. 2 g/L-reactor and 3 g/L-reactor). The metagenomic analysis showed that only the microbes associated with LCFA degradation could encode proteins related to "chemotaxis" and "flagellar assembly", which promoted the ability to move towards the LCFA sources so as to degrade them. Moreover, the syntrophic interactions found between Syntrophomonas sp. together with Methanosarcina sp. were possibly assigned to the menaquinone-electron transfer. Finally, it was proven that a previously exposed to LCFA inoculum is more efficient in the degradation process of LCFA due to the specialization of the microbial consortium. PMID:27353502

  2. Long-Chain Polyunsaturated Fatty Acids in Inborn Errors of Metabolism

    Directory of Open Access Journals (Sweden)

    Katalin Fekete

    2010-09-01

    Full Text Available The treatment of children with inborn errors of metabolism (IEM is mainly based on restricted dietary intake of protein-containing foods. However, dietary protein restriction may not only reduce amino acid intake, but may be associated with low intake of polyunsaturated fatty acids as well. This review focuses on the consequences of dietary restriction in IEM on the bioavailability of long-chain polyunsaturated fatty acids (LCPUFAs and on the attempts to ameliorate these consequences. We were able to identify during a literature search 10 observational studies investigating LCPUFA status in patients with IEM and six randomized controlled trials (RCTs reporting effect of LCPUFA supplementation to the diet of children with IEM. Decreased LCPUFA status, in particular decreased docosahexaenoic acid (DHA status, has been found in patients suffering from IEM based on the evidence of observational studies. LCPUFA supplementation effectively improves DHA status without detectable adverse reactions. Further research should focus on functional outcomes of LCPUFA supplementation in children with IEM.

  3. Flow-induced Crystallization of Long Chain Aliphatic Polyamides under a Complex Flow Field

    Science.gov (United States)

    Dong, Xia; Gao, Yunyun; Wang, Lili; Wang, Dujin

    The present work deals with the flow-induced multiple orientations and crystallization structure of polymer melts under a complex flow field. This complex flow field is characteristic of the consistent coupling of extensional ``pulse'' and closely followed shear flow in a narrow channel. Utilizing an ingenious combination of an advanced micro-injection device and long chain aliphatic polyamides, the flow-induced crystallization morphology was well preserved for ex-situ synchrotron micro-focused wide angle X-ray scattering as well as small angle X-ray scattering. The experimental results clearly indicate that the effect of extensional pulse on the polymer melt is restrained and further diminished due to either the transverse tumble of fountain flow or the rapid retraction of stretched high molecular weight tails. However, the residual shish-kebab structures in the core layer of the far-end of channel suggest that the effect of extensional pulse should be considered in the small-scaled geometries or under the high strain rate condition. The authors thank the financial support from MOST (2013BAE02B02, 2014CB643600) and NSFC(21574140).

  4. Antibacterial effects of long-chain polyphosphates on selected spoilage and pathogenic bacteria.

    Science.gov (United States)

    Obritsch, Jeremy A; Ryu, Dojin; Lampila, Lucina E; Bullerman, Lloyd B

    2008-07-01

    The antimicrobial activities of four long-chain food-grade polyphosphates were studied at concentrations allowed in the food industry (<5,000 ppm) in defined basal media by determining the inhibition of growth of three gram-negative and four gram-positive spoilage and pathogenic bacteria. Both generation time and lag phase of Escherichia coli K-12, E. coli O157: H7, and Salmonella Typhimurium were increased with all of the polyphosphates tested. Bacillus subtilis and Staphylococcus aureus were more sensitive to polyphosphates, but not in all cases, with multiphased growth. The growth of Lactobacillus plantarum was inhibited by polyphosphates at concentrations above 750 ppm, but the lag time of Listeria monocytogenes was shortened by the presence of polyphosphates. No single polyphosphate was maximally inhibitory against all bacteria. Polyphosphates with chain lengths of 12 to 15 were significantly different from those with chain lengths of 18 to 21 depending on the organism and concentrations of polyphosphate used. Overall, higher polyphosphate concentrations resulted in greater inhibition of bacterial growth. PMID:18680939

  5. Extracorporeal membrane oxygenation promotes long chain fatty acid oxidation in the immature swine heart in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Kajimoto, Masaki; O' Kelly-Priddy, Colleen M.; Ledee, Dolena R.; Xu, Chun; Isern, Nancy G.; Olson, Aaron; Portman, Michael A.

    2013-09-01

    Extracorporeal membrane oxygenation (ECMO) supports infants and children with severe cardiopulmonary compromise. Nutritional support for these children includes provision of medium- and long-chain fatty acids (FAs). However, ECMO induces a stress response, which could limit the capacity for FA oxidation. Metabolic impairment could induce new or exacerbate existing myocardial dysfunction. Using a clinically relevant piglet model, we tested the hypothesis that ECMO maintains the myocardial capacity for FA oxidation and preserves myocardial energy state. Provision of 13-Carbon labeled medium-chain FA (octanoate), longchain free FAs (LCFAs), and lactate into systemic circulation showed that ECMO promoted relative increases in myocardial LCFA oxidation while inhibiting lactate oxidation. Loading of these labeled substrates at high dose into the left coronary artery demonstrated metabolic flexibility as the heart preferentially oxidized octanoate. ECMO preserved this octanoate metabolic response, but also promoted LCFA oxidation and inhibited lactate utilization. Rapid upregulation of pyruvate dehydrogenase kinase-4 (PDK4) protein appeared to participate in this metabolic shift during ECMO. ECMO also increased relative flux from lactate to alanine further supporting the role for pyruvate dehydrogenase inhibition by PDK4. High dose substrate loading during ECMO also elevated the myocardial energy state indexed by phosphocreatine to ATP ratio. ECMO promotes LCFA oxidation in immature hearts, while maintaining myocardial energy state. These data support the appropriateness of FA provision during ECMO support for the immature heart.

  6. Effect of headgroup-substrate interactions on the thermal behavior of long-chain amphiphiles

    Science.gov (United States)

    Singla, Saranshu; Zhu, He; Dhinojwala, Ali

    The structure of amphiphilic molecules at liquid/solid and solid/solid interfaces is relevant in understanding lubrication, colloid stabilization, chromatography, and nucleation. Here, we characterize the interfacial structures of long chain amphiphilic molecules with different head groups (OH, COOH, NH2) using interface-sensitive sum frequency generation (SFG) spectroscopy. The behavior of these self-assembled monolayers (SAMs) on sapphire substrate is recorded in situ as a function of temperature (above and below bulk Tm) using SFG. Previous studies using synchrotron X-ray reflectivity and SFG show that the melting point of an ordered hexadecanol monolayer is around 30°C above its bulk Tm. The thermal stability of the monolayer is explained due to strong hydrogen bonding interactions between the head-group and the sapphire substrate. The strength of these hydrogen-bonding interactions between substrate and different head groups is calculated using the Badger-Bauer equation. Below Tm, the ordered monolayer influenced the structure of the interfacial crystalline layer, and the transition from monolayer to the bulk crystalline phases. The results with different head groups will be presented.

  7. Enzymatic characterization of ELOVL1, a key enzyme in very long-chain fatty acid synthesis.

    Science.gov (United States)

    Schackmann, Martin J A; Ofman, Rob; Dijkstra, Inge M E; Wanders, Ronald J A; Kemp, Stephan

    2015-02-01

    X-linked adrenoleukodystrophy (X-ALD) is a neurometabolic disease that is caused by mutations in the ABCD1 gene. ABCD1 protein deficiency impairs peroxisomal very long-chain fatty acid (VLCFA) degradation resulting in increased cytosolic VLCFA-CoA levels, which are further elongated by the VLCFA-specific elongase, ELOVL1. In adulthood, X-ALD most commonly manifests as a gradually progressive myelopathy (adrenomyeloneuropathy; AMN) without any curative or disease modifying treatments. We recently showed that bezafibrate reduces VLCFA accumulation in X-ALD fibroblasts by inhibiting ELOVL1. Although, in a clinical trial, bezafibrate was unable to lower VLCFA levels in plasma or lymphocytes in X-ALD patients, inhibition of ELOVL1 remains an attractive therapeutic option. In this study, we investigated the kinetic characteristics of ELOVL1 using X-ALD fibroblasts and microsomal fractions from ELOVL1 over-expressing HEK293 cell lines and analyzed the inhibition kinetics of a series of fibrates. Our data show that the CoA esters of bezafibrate and gemfibrozil reduce chain elongation by specifically inhibiting ELOVL1. These fibrates can therefore serve as lead compounds for the development of more potent and more specific inhibitors for ELOVL1. PMID:25499606

  8. Alternative Sources of n-3 Long-Chain Polyunsaturated Fatty Acids in Marine Microalgae

    Directory of Open Access Journals (Sweden)

    João Varela

    2013-06-01

    Full Text Available The main source of n-3 long-chain polyunsaturated fatty acids (LC-PUFA in human nutrition is currently seafood, especially oily fish. Nonetheless, due to cultural or individual preferences, convenience, geographic location, or awareness of risks associated to fatty fish consumption, the intake of fatty fish is far from supplying the recommended dietary levels. The end result observed in most western countries is not only a low supply of n-3 LC-PUFA, but also an unbalance towards the intake of n-6 fatty acids, resulting mostly from the consumption of vegetable oils. Awareness of the benefits of LC-PUFA in human health has led to the use of fish oils as food supplements. However, there is a need to explore alternatives sources of LC-PUFA, especially those of microbial origin. Microalgae species with potential to accumulate lipids in high amounts and to present elevated levels of n-3 LC-PUFA are known in marine phytoplankton. This review focuses on sources of n-3 LC-PUFA, namely eicosapentaenoic and docosahexaenoic acids, in marine microalgae, as alternatives to fish oils. Based on current literature, examples of marketed products and potentially new species for commercial exploitation are presented.

  9. Energy optimal routing for long chain-type wireless sensor networks in underground mines

    Institute of Scientific and Technical Information of China (English)

    Jiang Haifeng; Qian Jiansheng; Sun Yanjing; Zhang Guoyong

    2011-01-01

    Wireless sensor networks are useful complements to existing monitoring systems in underground mines.They play an important role of enhancing and improving coverage and flexibility of safety monitoring systems. Regions prone to danger and enyironments after disasters in underground mines require saving and balancing energy consumption of nodes to prolong the lifespan of networks. Based on the structure of a tunnel, we present a Long Chain-type Wireless Sensor Network (LC-WSN) to monitor the safety of underground mine tunnels. We define the optimal transmission distance and the range of the key region and present an Energy Optimal Routing (EOR) algorithm for LC-WSN to balance the energy consumption of nodes and maximize the lifespan of networks. EOR constructs routing paths based on an optimal transmission distance and uses an energy balancing strategy in the key region. Simulation results show that the EOR algorithm extends the lifespan of a network, balances the energy consumption of nodes in the key region and effectively limits the length of routing paths, compared with similar algorithms.

  10. Gating of the mitochondrial permeability transition pore by long chain fatty acyl analogs in vivo.

    Science.gov (United States)

    Samovski, Dmitri; Kalderon, Bella; Yehuda-Shnaidman, Einav; Bar-Tana, Jacob

    2010-03-01

    The role played by long chain fatty acids (LCFA) in promoting energy expenditure is confounded by their dual function as substrates for oxidation and as putative classic uncouplers of mitochondrial oxidative phosphorylation. LCFA analogs of the MEDICA (MEthyl-substituted DICarboxylic Acids) series are neither esterified into lipids nor beta-oxidized and may thus simulate the uncoupling activity of natural LCFA in vivo, independently of their substrate role. Treatment of rats or cell lines with MEDICA analogs results in low conductance gating of the mitochondrial permeability transition pore (PTP), with 10-40% decrease in the inner mitochondrial membrane potential. PTP gating by MEDICA analogs is accounted for by inhibition of Raf1 expression and kinase activity, resulting in suppression of the MAPK/RSK1 and the adenylate cyclase/PKA transduction pathways. Suppression of RSK1 and PKA results in a decrease in phosphorylation of their respective downstream targets, Bad(Ser-112) and Bad(Ser-155). Decrease in Bad(Ser-112, Ser-155) phosphorylation results in increased binding of Bad to mitochondrial Bcl2 with concomitant displacement of Bax, followed by PTP gating induced by free mitochondrial Bax. Low conductance PTP gating by LCFA/MEDICA may account for their thyromimetic calorigenic activity in vivo. PMID:20037159

  11. High contents of very long-chain polyunsaturated fatty acids in different moss species.

    Science.gov (United States)

    Beike, Anna K; Jaeger, Carsten; Zink, Felix; Decker, Eva L; Reski, Ralf

    2014-02-01

    Polyunsaturated fatty acids (PUFAs) are important cellular compounds with manifold biological functions. Many PUFAs are essential for the human diet and beneficial for human health. In this study, we report on the high amounts of very long-chain (vl) PUFAs (≥C₂₀) such as arachidonic acid (AA) in seven moss species. These species were established in axenic in vitro culture, as a prerequisite for comparative metabolic studies under highly standardized laboratory conditions. In the model organism Physcomitrella patens, tissue-specific differences in the fatty acid compositions between the filamentous protonema and the leafy gametophores were observed. These metabolic differences correspond with differential gene expression of fatty acid desaturase (FADS)-encoding genes in both developmental stages, as determined via microarray analyses. Depending on the developmental stage and the species, AA amounts for 6-31 %, respectively, of the total fatty acids. Subcellular localization of the corresponding FADS revealed the endoplasmic reticulum as the cellular compartment for AA synthesis. Our results show that vlPUFAs are highly abundant metabolites in mosses. Standardized cultivation techniques using photobioreactors along with the availability of the P. patens genome sequence and the high rate of homologous recombination are the basis for targeted metabolic engineering in moss. The potential of producing vlPUFAs of interest from mosses will be highlighted as a promising area in plant biotechnology. PMID:24170342

  12. Long-chain saturated and monounsaturated fatty acids associate with development of premature infants up to 18 months of age.

    Science.gov (United States)

    Strandvik, Birgitta; Ntoumani, Eleni; Lundqvist-Persson, Cristina; Sabel, Karl-Göran

    2016-04-01

    Myelination is important perinatally and highly dependent on long-chain saturated and monounsaturated fatty acids. Long-chain polyunsaturated fatty acids, nowadays often supplemented, inhibit oleic acid synthesis. Using data from a premature cohort, we studied if nervonic, lignoceric and oleic acids correlated to growth and early development up to 18 months corrected age. Small for gestational age infants had lower concentrations than infants appropriate for gestational age. Only oleic acid was negatively correlated to long-chain polyunsaturated fatty acids. Oleic and lignoceric acids correlated to social interaction at one month, and nervonic acid to mental, psychomotor and behavioral development at 6, 10 and 18 months, also when adjusted for several confounders. Negative association between oleic acid and long-chain polyunsaturated fatty acids suggests inhibition of delta-9 desaturase, and nervonic acid´s divergent correlation to lignoceric and oleic acids suggests different metabolism in neonatal period. Our results may have implications for the supplementation of premature infants. PMID:26858144

  13. TORC1 Inhibits GSK3-Mediated Elo2 Phosphorylation to Regulate Very Long Chain Fatty Acid Synthesis and Autophagy

    DEFF Research Database (Denmark)

    Zimmermann, Christine; Santos, Aline; Gable, Kenneth; Epstein, Sharon; Gururaj, Charulatha; Chymkowitch, Pierre; Pultz, Dennis; Rødkær, Steven V; Clay, Lorena; Bjørås, Magnar; Barral, Yves; Chang, Amy; Færgeman, Nils J.; Dunn, Teresa M; Riezman, Howard; Enserink, Jorrit M

    2013-01-01

    Very long chain fatty acids (VLCFAs) are essential fatty acids with multiple functions, including ceramide synthesis. Although the components of the VLCFA biosynthetic machinery have been elucidated, how their activity is regulated to meet the cell's metabolic demand remains unknown. The goal of ...

  14. Reduced absorption of long-chain fatty acids during methotrexate-induced gastrointestinal mucositis in the rat

    NARCIS (Netherlands)

    Fijlstra, Margot; Tissing, Wim J. E.; Stellaard, Frans; Verkade, Henkjan J.; Rings, Edmond H. H. M.

    2013-01-01

    Background & aims: Patients with chemotherapy-induced gastrointestinal mucositis suffer from weight loss and possibly malabsorption. Since long-chain fatty acids serve important functions in the body, we aimed to determine the intestinal capacity of fat absorption in rats with and without methotrexa

  15. Long-chain acyl-CoA-dependent regulation of gene expression in bacteria, yeast and mammals

    DEFF Research Database (Denmark)

    Black, P N; Færgeman, Nils J.; DiRusso, C C

    2000-01-01

    Fatty acyl-CoA thioesters are essential intermediates in lipid metabolism. For many years there have been numerous conflicting reports concerning the possibility that these compounds also serve regulatory functions. In this review, we examine the evidence that long-chain acyl-CoA is a regulatory ...

  16. Long-chain Acyl-CoA is not primarily increased in myotubes established from type 2 diabetic subjects

    DEFF Research Database (Denmark)

    Just, Malene; Faergeman, Nils J; Knudsen, Jens; Beck-Nielsen, Henning; Gaster, Michael

    2006-01-01

    Accumulation of intramuscular long-chain acyl-CoA esters (LCACoA) has previously in animal and human models been suggested to play an important role in lipid induced insulin resistance. The aim of this study was to examine whether myotubes established from type 2 diabetic (T2D) subjects and lean ...

  17. Identification of very long chain fatty acids from sugar cane wax by atmospheric pressure chemical ionization liquid chromatography - mass spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Sigler, Karel

    2006-01-01

    Roč. 67, - (2006), s. 916-923. ISSN 0031-9422 Institutional research plan: CEZ:AV0Z50200510 Keywords : sugar cane wax * very long chain fatty acids * liquid chromatography Subject RIV: EE - Microbiology, Virology Impact factor: 2.417, year: 2006

  18. Activity and viability of methanogens in anaerobic digestion of unsaturated and saturated long-chain fatty acids

    NARCIS (Netherlands)

    Sousa, D.Z.; Salvador, A.F.; Ramos, J.; Guedes, A.P.; Barbosa, S.; Stams, A.J.M.; Alves, M.M.; Pereira, M.A.

    2013-01-01

    Lipids can be anaerobically digested to methane, but methanogens are often considered to be highly sensitive to the long-chain fatty acids (LCFA) deriving from lipids hydrolysis. In this study, the effect of unsaturated (oleate [C18:1]) and saturated (stearate [C18:0] and palmitate [C16:0]) LCFA tow

  19. Fibroblast Growth Factor-21 and the Beneficial Effects of Long-Chain n-3 Polyunsaturated Fatty Acids

    Czech Academy of Sciences Publication Activity Database

    Villarroya, J.; Flachs, Pavel; Redondo-Angulo, I.; Giralt, M.; Medříková, Daša; Villarroya, F.; Kopecký, Jan; Planavila, A.

    2014-01-01

    Roč. 49, č. 11 (2014), s. 1081-1089. ISSN 0024-4201 R&D Projects: GA ČR(CZ) GA13-00871S Institutional support: RVO:67985823 Keywords : fibroblast growth factor-21 * long-chain n-3 polyunsaturated fatty acids Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.854, year: 2014

  20. Micellization of long-chain ionic liquids in deep eutectic solvents.

    Science.gov (United States)

    Tan, Xiuniang; Zhang, Jianling; Luo, Tian; Sang, Xinxin; Liu, Chengcheng; Zhang, Bingxing; Peng, Li; Li, Wei; Han, Buxing

    2016-06-28

    The aggregation behavior of the ionic liquid (IL) 1-alkyl-3-methylimidazolium chloride with different alkyl chain lengths in a deep eutectic solvent (DES, composed of choline chloride and glycerol in a 1 : 2 mole ratio) was studied for the first time. The critical micellar concentration, micellar size and intermolecular interactions in IL/DES solutions were investigated by different techniques including the fluorescence probe technique, small angle X-ray scattering and Fourier transform infrared spectroscopy. The solvophobic effect dominates the micellization of CnmimCl in DES and the intermolecular hydrogen-bond interaction plays a positive role to promote micelle formation. The micellar solutions were utilized for the synthesis of the water-unstable metal-organic framework Cu3(BTC)2 (BTC = 1,3,5-benzenetricarboxylate) at room temperature. X-Ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption isotherms confirm the formation of crystalline Cu3(BTC)2 nanocrystals with mesoporous structures. The morphologies and porosity properties of Cu3(BTC)2 nanocrystals can be modulated by varying the concentration of CnmimCl. PMID:27222006

  1. Intracellular long-chain acyl CoAs activate TRPV1 channels.

    Directory of Open Access Journals (Sweden)

    Yi Yu

    Full Text Available TRPV1 channels are an important class of membrane proteins that play an integral role in the regulation of intracellular cations such as calcium in many different tissue types. The anionic phospholipid phosphatidylinositol 4,5-bisphosphate (PIP2 is a known positive modulator of TRPV1 channels and the negatively charged phosphate groups interact with several basic amino acid residues in the proximal C-terminal TRP domain of the TRPV1 channel. We and other groups have shown that physiological sub-micromolar levels of long-chain acyl CoAs (LC-CoAs, another ubiquitous anionic lipid, can also act as positive modulators of ion channels and exchangers. Therefore, we investigated whether TRPV1 channel activity is similarly regulated by LC-CoAs. Our results show that LC-CoAs are potent activators of the TRPV1 channel and interact with the same PIP2-binding residues in TRPV1. In contrast to PIP2, LC-CoA modulation of TRPV1 is independent of Ca2+i, acting in an acyl side-chain saturation and chain-length dependent manner. Elevation of LC-CoAs in intact Jurkat T-cells leads to significant increases in agonist-induced Ca2+i levels. Our novel findings indicate that LC-CoAs represent a new fundamental mechanism for regulation of TRPV1 channel activity that may play a role in diverse cell types under physiological and pathophysiological conditions that alter fatty acid transport and metabolism such as obesity and diabetes.

  2. PTH1 receptor is involved in mediating cellular response to long-chain polyunsaturated fatty acids.

    Directory of Open Access Journals (Sweden)

    Jose Candelario

    Full Text Available The molecular pathways by which long chain polyunsaturated fatty acids (LCPUFA influence skeletal health remain elusive. Both LCPUFA and parathyroid hormone type 1 receptor (PTH1R are known to be involved in bone metabolism while any direct link between the two is yet to be established. Here we report that LCPUFA are capable of direct, PTH1R dependent activation of extracellular ligand-regulated kinases (ERK. From a wide range of fatty acids studied, varying in chain length, saturation, and position of double bonds, eicosapentaenoic (EPA and docosahexaenoic fatty acids (DHA caused the highest ERK phosphorylation. Moreover, EPA potentiated the effect of parathyroid hormone (PTH(1-34 in a superagonistic manner. EPA or DHA dependent ERK phosphorylation was inhibited by the PTH1R antagonist and by knockdown of PTH1R. Inhibition of PTH1R downstream signaling molecules, protein kinases A (PKA and C (PKC, reduced EPA and DHA dependent ERK phosphorylation indicating that fatty acids predominantly activate G-protein pathway and not the β-arrestin pathway. Using picosecond time-resolved fluorescence microscopy and a genetically engineered PTH1R sensor (PTH-CC, we detected conformational responses to EPA similar to those caused by PTH(1-34. PTH1R antagonist blocked the EPA induced conformational response of the PTH-CC. Competitive binding studies using fluorescence anisotropy technique showed that EPA and DHA competitively bind to and alter the affinity of PTH1 receptor to PTH(1-34 leading to a superagonistic response. Finally, we showed that EPA stimulates protein kinase B (Akt phosphorylation in a PTH1R-dependent manner and affects the osteoblast survival pathway, by inhibiting glucocorticoid-induced cell death. Our findings demonstrate for the first time that LCPUFAs, EPA and DHA, can activate PTH1R receptor at nanomolar concentrations and consequently provide a putative molecular mechanism for the action of fatty acids in bone.

  3. Drug discovery opportunities and challenges at G protein coupled receptors for long chain free fatty acids

    Directory of Open Access Journals (Sweden)

    Nicholas D Holliday

    2012-01-01

    Full Text Available Discovery of G protein coupled receptors for long chain free fatty acids (FFAs, FFA1 (GPR40 and GPR120, has expanded our understanding of these nutrients as signalling molecules. These receptors have emerged as important sensors for FFA levels in the circulation or the gut lumen, based on evidence from in vitro and rodent models, and an increasing number of human studies. Here we consider their promise as therapeutic targets for metabolic disease, including type 2 diabetes and obesity. FFA1 directly mediates acute FFA-induced glucose-stimulated insulin secretion in pancreatic beta-cells, while GPR120 and FFA1 trigger release of incretins from intestinal endocrine cells, and so indirectly enhance insulin secretion and promote satiety. GPR120 signalling in adipocytes and macrophages also results in insulin sensitizing and beneficial anti-inflammatory effects. Drug discovery has focussed on agonists to replicate acute benefits of FFA receptor signalling, with promising early results for FFA1 agonists in man. Controversy surrounding chronic effects of FFA1 on beta-cells illustrates that long term benefits of antagonists also need exploring. It has proved challenging to generate highly selective potent ligands for FFA1 or GPR120 subtypes, given that both receptors have hydrophobic orthosteric binding sites, which are not completely defined and have modest ligand affinity. Structure activity relationships are also reliant on functional read outs, in the absence of robust binding assays to provide direct affinity estimates. Nevertheless synthetic ligands have already helped dissect specific contributions of FFA1 and GPR120 signalling from the many possible cellular effects of FFAs. Approaches including use of fluorescent ligand binding assays, and targeting allosteric receptor sites, may improve further preclinical ligand development at these receptors, to exploit their unique potential to target multiple facets of diabetes.

  4. Reinvestigation of the radiopharmaceutical production of radioiodinated long-chain fatty acids. Vol. 3

    International Nuclear Information System (INIS)

    An improved and simple radiopharmaceutical production technique for radioiodination of ω - (Br) or (I) fatty acids (ω) - Br or I-(C H2)n Co2 H, where n = 16 to 17 with Na13I for myocardial imaging study is described. The technique of production is reported here based on an isotope or non - isotopic exchange reaction between the inactive halogenated fatty acids and lyophilized ethanolic solution of Na131 I (previously dispensed in 0.02 M NaOH solution) at 80 Degree C within 30 min in absolute ethanol (dehydrated and redistill at 78.5 to 80 degree C over nitrobenzene b.p. 208 to 212 degree C). Although considerable radiochemical yields have been obtained using a wide variety of organic solvents as an isotropic or non-isotropic exchange media such as acetone, methyl ethyl ketone, benzene as well as di-n-propyl ketone; certain problems due to the evaporation of these solvents during the process of purification have been observed. These problems were completely avoided by the initial dissolution of the reactants in dehydrated ethyl alcohol which facilitate direct dispensing of the final radioiodinated acids in diluted human serum albumen without any decomposition. Basically, following the radioiodination process the radioiodinated fatty acids ethanolic solution is passed through out an AgCl-impregnated filter to remove the untreated inorganic radioiodine (2 to 5%). The final pure solution (containing over 99.o% radioiodinated pure fatty acids) is dispensed in human serum albumen (4%), and then sterilized by passing it through 0.22 mum milli pore bacterial filter. The technique is being applied for the radiopharmaceutical production of radioiodinated-phenyl long-chain fatty acids such as iodo phenoxy-, and iodobenzamido-heptadecanoic acids. 3 figs

  5. Quantitative characterization of short- and long-chain perfluorinated acids in solid matrices in Shanghai, China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fei [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Zhang, Chaojie, E-mail: myrazh@mail.tongji.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China); Qu, Yan; Chen, Jing; Chen, Ling; Liu, Ying; Zhou, Qi [State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092 (China)

    2010-01-01

    Perfluorinated acids (PFAs) have been recognized as emerging environmental pollutants because of their widespread occurrences, persistence, and bioaccumulative and toxicological effects. PFAs have been detected in aquatic environment and biota in China, but the occurrences of these chemicals have not been reported in solid matrices in China. In the present study, short- and long-chain PFAs (C2-C14) have been quantitatively determined in solid matrices including sediments, soils and sludge collected in Shanghai, China. The results indicate that sludge contains more PFAs than sediments and soils, and the total PFAs concentrations in sediments, soil and sludge are 62.5-276 ng g{sup -1}, 141-237 ng g{sup -1} and 413-755 ng g{sup -1}, respectively. In most cases, trifluoroacetic acid was the major PFA and accounted for 22-90% of the total PFAs. Although the levels of perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) were not only lower than trifluoroacetic acid, but also lower than some short-chain PFCAs (

  6. Omega-3 long-chain fatty acids strongly induce angiopoietin-like 4 in humans.

    Science.gov (United States)

    Brands, Myrte; Sauerwein, Hans P; Ackermans, Mariette T; Kersten, Sander; Serlie, Mireille J

    2013-03-01

    Angiopoietin-like 4 (ANGPTL4) is a regulator of LPL activity. In this study we examined whether different fatty acids have a differential effect on plasma ANGPTL4 levels during hyperinsulinemia in healthy lean males. In 10 healthy lean males, 3 hyperinsulinemic euglycemic clamps were performed during concomitant 6 h intravenous infusion of soybean oil (Intralipid® rich in PUFA), olive oil (Clinoleic® rich in MUFA) and control saline. In 10 other healthy lean males, 2 hyperinsulinemic clamps were performed during infusion of a mixed lipid emulsion containing a mixture of fish oil (FO), medium-chain triglycerides (MCTs), and long-chain triglycerides (LCTs) (FO/MCT/LCT; SMOFlipid®) or saline. FFA levels of approximately 0.5 mmol/l were reached during each lipid infusion. Plasma ANGPTL4 decreased during hyperinsulinemia by 32% (18-52%) from baseline. This insulin-mediated decrease in ANGPTL4 concentrations was partially reduced during concomitant infusion of olive oil and completely blunted during concomitant infusion of soybean oil and FO/MCT/LCT. The reduction in insulin sensitivity was similar between all lipid infusions. In accordance, incubation of rat hepatoma cells with the polyunsaturated fatty acid C22:6 increased ANGPTL4 expression by 70-fold, compared with 27-fold by the polyunsaturated fatty acid C18:2, and 15-fold by the monounsaturated fatty acid C18:1. These results suggest that ANGPTL4 is strongly regulated by fatty acids in humans, and is also dependent on the type of fatty acid. PMID:23319744

  7. Dietary n-3 long chain polyunsaturated fatty acids in allergy prevention and asthma treatment.

    Science.gov (United States)

    Willemsen, Linette E M

    2016-08-15

    The rise in non-communicable diseases, such as allergies, in westernized countries links to changes in lifestyle and diet. N-3 long chain polyunsaturated fatty acids (LCPUFA) present in marine oils facilitate a favorable milieu for immune maturation and may contribute to allergy prevention. N-3 LCPUFA can suppress innate and adaptive immune activation and induce epigenetic changes. Murine studies convincingly show protective effects of fish oil, a source of n-3 LCPUFA, in food allergy and asthma models. Observational studies in human indicate that high dietary intake of n-3 LCPUFA and low intake of n-6 PUFA may protect against the development of allergic disease early in life. High n-6 PUFA intake is also associated with an increased asthma risk while n-3 LCPUFA may be protective and reduce symptoms. The quality of the marine oil used has impact on efficacy of allergy prevention and several observations link in particular n-3 LCPUFA DHA to allergy suppression. Randomized controlled trials indicate that optimal timing, duration and dosage of n-3 LC-PUFA is required to exert an allergy protective effect. Supplementation during early pregnancy and lactation has shown promising results regarding allergy prevention. However these findings should be confirmed in a larger cohort. Although clinical trials in asthma patients reveal no consistent clinical benefits of n-3 LCPUFA supplementation on lung function, it can suppress airway inflammation. Future food-pharma approaches may reveal whether adjunct therapy with dietary n-3 LCPUFA can improve allergy prevention or immunotherapy via support of allergen specific oral tolerance induction or contribute to the efficacy of drug therapy for asthma patients. PMID:27041644

  8. The possible role of long-chain, omega-3 fatty acids in human brain phylogeny.

    Science.gov (United States)

    Chamberlain, J G

    1996-01-01

    I propose that one of the key factors in human encephalization was increased HUFA intake, especially long-chain, omega-3 fatty acids from aquatic and terrestial meat source. This provided the needed neural membrane fluidity and transmitter/receptor functions for rapid acquisition of more advanced human traits and allowed the expansion of H. erectus into more northern climates. The human brain initially could build ecophenotypically, or adaptive/directed mutationally upon previously evolved mammalian sensor/motor structures, and could rapidly expand cognitive functions within a few million years; as more niches were invaded, more brain diversity was needed to guarantee reproductive success. The metabolically expensive and expanding brain was nutritionally and biochemically set, as it were, for rapid accommodation to tool making, rock throwing, culture language, electronics, and the eventual endless discussion and writings about the brain itself, the evolution of consciousness, and the mid-bran problem [107]. All of this fits, no matter which theory of human evolution one adheres to--i.e., out of Africa, multiregional, etc.--or even the precis fossil chronology [108]. This proposal, based as it is on known facts and certain assumptions appears logical, simple, and satisfying, but it may be wrong. Yet Charles Darwin himself would have approved, because as he so aptly said: false facts are highly injurious to the progress of science, for they often endure long; but false views, if supported by some evidence do little harm for everyone takes a salutory pleasure in providing their falseness; and when this is done our path toward error is closed and the road to truth is often opened. [109]. PMID:8657555

  9. Long-chain n-3 fatty acids and inflammation: potential application in surgical and trauma patients

    Directory of Open Access Journals (Sweden)

    Calder P.C.

    2003-01-01

    Full Text Available Lipids used in nutritional support of surgical or critically ill patients have been based on soybean oil, which is rich in the n-6 fatty acid linoleic acid (18:2n-6. Linoleic acid is the precursor of arachidonic acid (20:4n-6. In turn, arachidonic acid in cell membrane phospholipids is the substrate for the synthesis of a range of biologically active compounds (eicosanoids including prostaglandins, thromboxanes, and leukotrienes. These compounds can act as mediators in their own right and can also act as regulators of other processes, such as platelet aggregation, blood clotting, smooth muscle contraction, leukocyte chemotaxis, inflammatory cytokine production, and immune function. There is a view that an excess of n-6 fatty acids should be avoided since this could contribute to a state where physiological processes become dysregulated. One alternative is the use of fish oil. The rationale of this latter approach is that fish oil contains long chain n-3 fatty acids, such as eicosapentaenoic acid. When fish oil is provided, eicosapentaenoic acid is incorporated into cell membrane phospholipids, partly at the expense of arachidonic acid. Thus, there is less arachidonic acid available for eicosanoid synthesis. Hence, fish oil decreases production of prostaglandins like PGE2 and of leukotrienes like LTB4. Thus, n-3 fatty acids can potentially reduce platelet aggregation, blood clotting, smooth muscle contraction, and leukocyte chemotaxis, and can modulate inflammatory cytokine production and immune function. These effects have been demonstrated in cell culture, animal feeding and healthy volunteer studies. Fish oil decreases the host metabolic response and improves survival to endotoxin in laboratory animals. Recently clinical studies performed in various patient groups have indicated benefit from this approach.

  10. Mechanisms involved in the selective transfer of long chain polyunsaturted fatty acids to the fetus

    Directory of Open Access Journals (Sweden)

    Alfonso eGil-Sánchez

    2011-09-01

    Full Text Available The concentration of long chain polyunsaturated fatty acid (LCPUFA in the fetal brain increases dramatically from the third trimester until 18 months of life. Several studies have shown an association between the percentage of maternal plasma docosahexaenoic acid (DHA during gestation and development of the cognitive functions in the neonate. Since only very low levels of LCPUFA are synthesized in the fetus and placenta, their primary source for the fetus is that of maternal origin. Both in vitro and human in vivo studies using labelled fatty acids have shown the preferential transfer of LCPUFA from the placenta to the fetus compared with other fatty acids, although the mechanisms involved are still uncertain. The placenta takes up circulating maternal non-esterified fatty acids (NEFA and fatty acids released mainly by maternal lipoprotein lipase and endothelial lipase. These NEFA may enter the cell by passive diffusion or by means of membrane carrier proteins. Once in the cytosol, NEFA bind to cytosolic fatty acid-binding proteins for transfer to the fetal circulation or can be oxidized within the trophoblasts and even re-esterified and stored in lipid droplets (LD. Although trophoblast cells are not specialized in lipid storage, LCPUFA may up-regulate peroxisome proliferator activated receptor-γ (PPARγ and hence the gene expression of fatty acid transport carriers, fatty acid acyl-CoA synthetases and adipophilin or other enzymes related with lipolysis, modifying their rate of placental transfer and metabolization. The placental transfer of LCPUFA during pregnancy seems to be a key factor in the neurological development of the fetus. Increased knowledge on the factors that modify placental transfer of fatty acids would contribute to our understanding of this complex process.

  11. Antibacterial activity of long-chain polyunsaturated fatty acids against Propionibacterium acnes and Staphylococcus aureus.

    Science.gov (United States)

    Desbois, Andrew P; Lawlor, Keelan C

    2013-11-01

    New compounds are needed to treat acne and superficial infections caused by Propionibacterium acnes and Staphylococcus aureus due to the reduced effectiveness of agents used at present. Long-chain polyunsaturated fatty acids (LC-PUFAs) are attracting attention as potential new topical treatments for Gram-positive infections due to their antimicrobial potency and anti-inflammatory properties. This present study aimed to investigate the antimicrobial effects of six LC-PUFAs against P. acnes and S. aureus to evaluate their potential to treat infections caused by these pathogens. Minimum inhibitory concentrations were determined against P. acnes and S. aureus, and the LC-PUFAs were found to inhibit bacterial growth at 32-1024 mg/L. Generally, P. acnes was more susceptible to the growth inhibitory actions of LC-PUFAs, but these compounds were bactericidal only for S. aureus. This is the first report of antibacterial activity attributed to 15-hydroxyeicosapentaenoic acid (15-OHEPA) and 15-hydroxyeicosatrienoic acid (HETrE), while the anti-P. acnes effects of the six LC-PUFAs used herein are novel observations. During exposure to the LC-PUFAs, S. aureus cells were killed within 15-30 min. Checkerboard assays demonstrated that the LC-PUFAs did not antagonise the antimicrobial potency of clinical agents used presently against P. acnes and S. aureus. However, importantly, synergistic interactions against S. aureus were detected for combinations of benzoyl peroxide with 15-OHEPA, dihomo-γ-linolenic acid (DGLA) and HETrE; and neomycin with 15-OHEPA, DGLA, eicosapentaenoic acid, γ-linolenic acid and HETrE. In conclusion, LC-PUFAs warrant further evaluation as possible new agents to treat skin infections caused by P. acnes and S. aureus, especially in synergistic combinations with antimicrobial agents already used clinically. PMID:24232668

  12. Antibacterial Activity of Long-Chain Polyunsaturated Fatty Acids against Propionibacterium acnes and Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Andrew P. Desbois

    2013-11-01

    Full Text Available New compounds are needed to treat acne and superficial infections caused by Propionibacterium acnes and Staphylococcus aureus due to the reduced effectiveness of agents used at present. Long-chain polyunsaturated fatty acids (LC-PUFAs are attracting attention as potential new topical treatments for Gram-positive infections due to their antimicrobial potency and anti-inflammatory properties. This present study aimed to investigate the antimicrobial effects of six LC-PUFAs against P. acnes and S. aureus to evaluate their potential to treat infections caused by these pathogens. Minimum inhibitory concentrations were determined against P. acnes and S. aureus, and the LC-PUFAs were found to inhibit bacterial growth at 32–1024 mg/L. Generally, P. acnes was more susceptible to the growth inhibitory actions of LC-PUFAs, but these compounds were bactericidal only for S. aureus. This is the first report of antibacterial activity attributed to 15-hydroxyeicosapentaenoic acid (15-OHEPA and 15-hydroxyeicosatrienoic acid (HETrE, while the anti-P. acnes effects of the six LC-PUFAs used herein are novel observations. During exposure to the LC-PUFAs, S. aureus cells were killed within 15–30 min. Checkerboard assays demonstrated that the LC-PUFAs did not antagonise the antimicrobial potency of clinical agents used presently against P. acnes and S. aureus. However, importantly, synergistic interactions against S. aureus were detected for combinations of benzoyl peroxide with 15-OHEPA, dihomo-γ-linolenic acid (DGLA and HETrE; and neomycin with 15-OHEPA, DGLA, eicosapentaenoic acid, γ-linolenic acid and HETrE. In conclusion, LC-PUFAs warrant further evaluation as possible new agents to treat skin infections caused by P. acnes and S. aureus, especially in synergistic combinations with antimicrobial agents already used clinically.

  13. Dietary long-chain polyunsaturated fatty acids upregulate expression of FADS3 transcripts.

    Science.gov (United States)

    Reardon, Holly T; Hsieh, Andrea T; Park, Woo Jung; Kothapalli, Kumar S D; Anthony, Joshua C; Nathanielsz, Peter W; Brenna, J Thomas

    2013-01-01

    The fatty acid desaturase (FADS) gene family at 11q12-13.1 includes FADS1 and FADS2, both known to mediate biosynthesis of omega-3 and omega-6 long-chain polyunsaturated fatty acids (LCPUFA). FADS3 is a putative desaturase due to its sequence similarity with FADS1 and FADS2, but its function is unknown. We have previously described 7 FADS3 alternative transcripts (AT) and 1 FADS2 AT conserved across multiple species. This study examined the effect of dietary LCPUFA levels on liver FADS gene expression in vivo and in vitro, evaluated by qRT-PCR. Fourteen baboon neonates were randomized to three diet groups for their first 12 weeks of life, C: Control, no LCPUFA, L: 0.33% docosahexaenoic acid (DHA)/0.67% arachidonic acid (ARA) (w/w); and L3: 1.00% DHA/0.67% ARA (w/w). Liver FADS1 and both FADS2 transcripts were downregulated by at least 50% in the L3 group compared to controls. In contrast, FADS3 AT were upregulated (L3 > C), with four transcripts significantly upregulated by 40% or more. However, there was no evidence for a shift in liver fatty acids to coincide with increased FADS3 expression. Significant upregulation of FADS3 AT was also observed in human liver-derived HepG2 cells after DHA or ARA treatment. The PPARγ antagonist GW9662 prevented FADS3 upregulation, while downregulation of FADS1 and FADS2 was unaffected. Thus, FADS3 AT were directly upregulated by LCPUFA by a PPARγ-dependent mechanism unrelated to regulation of other desaturases. This opposing pattern and mechanism of regulation suggests a dissimilar function for FADS3 AT compared to other FADS gene products. PMID:22398025

  14. Nutritional regulation of long-chain PUFA biosynthetic genes in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Gregory, Melissa K; Collins, Robert O; Tocher, Douglas R; James, Michael J; Turchini, Giovanni M

    2016-05-01

    Most studies on dietary vegetable oil in rainbow trout (Oncorhynchus mykiss) have been conducted on a background of dietary EPA (20 : 5n-3) and DHA (22 : 6n-3) contained in the fishmeal used as a protein source in aquaculture feed. If dietary EPA and DHA repress their endogenous synthesis from α-linolenic acid (ALA, 18 : 3n-3), then the potential of ALA-containing vegetable oils to maintain tissue EPA and DHA has been underestimated. We examined the effect of individual dietary n-3 PUFA on the expression of the biosynthetic genes required for metabolism of ALA to DHA in rainbow trout. A total of 720 juvenile rainbow trout were allocated to twenty-four experimental tanks and assigned one of eight diets. The effect of dietary ALA, EPA or DHA, in isolation or in combination, on hepatic expression of fatty acyl desaturase (FADS)2a(Δ6), FADS2b(Δ5), elongation of very long-chain fatty acid (ELOVL)5 and ELOVL2 was examined after 3 weeks of dietary intervention. The effect of these diets on liver and muscle phospholipid PUFA composition was also examined. The expression levels of FADS2a(Δ6), ELOVL5 and ELOVL2 were highest when diets were high in ALA, with no added EPA or DHA. Under these conditions ALA was readily converted to tissue DHA. Dietary DHA had the largest and most consistent effect in down-regulating the gene expression of all four genes. The ELOVL5 expression was the least responsive of the four genes to dietary n-3 PUFA changes. These findings should be considered when optimising aquaculture feeds containing vegetable oils and/or fish oil or fishmeal to achieve maximum DHA synthesis. PMID:26987422

  15. Lithium Alkyl Exchange Equilibria

    International Nuclear Information System (INIS)

    Kinetic analyses of two types of exchange reactions of organo- lithium reagents, both alkyl and aryl types, RLi, have been made: (1) halogen-metal interchange with alkyl and aryl halides, R'X, and (2) hydrogen-metal interchange (commonly called metallation) with aromatic hydrocarbons, R'H. Rates of these RLi + R'X ⇄ RX + R'Li; (1) . RLi + R'H ⇄ RH+ R'Li (2) reactions have been determined, conditions under which the systems attain equilibrium have been established, and the positions of equilibrium measured, all as functions of the reactants, solvents and catalysts employed. Concerning halogen-lithium interchange between alkyl groups (1), the conclusion is reached that equilibration proceeds to yield the less sterically demanding alkyl group attached to lithium. The data show, for example, that isobutyllithium is much less stable than n-butyllithium, and again, that 2,6-dimethyl- phenyllithium is much less stable than phenyllithium. The exchange is general with iodides, occurs with some bromides and does not occur with chlorides. The exchange is quite slow in hydrocarbon media and is catalysed by relatively small amounts of ethers. In the presence of the optically active methyl ether of menthol, methyl iodide exchanges with racemic s-butyllithium to give optically active s-butyl iodide. In work with the second reaction, hydrogen-lithium interchange (2), nuclear magnetic resonance spectrometry has been used for rate studies. Catalysts (Lewis bases) have been evolved for establishing equilibria in rather unreactive systems, e.g. phenyllithium can be demonstrated to exchange with benzene by labelling the latter radioactivity. From the correlations of structure and reactivity found in this study, the conclusion is reached that the basic alkyllithium structure is dimeric, R2Li2 The arrangement of the groups within this dimer satisfactorily explain the special steric effects noted in organolithium reagent stability. (author)

  16. Elongase reactions as control points in long-chain polyunsaturated fatty acid synthesis.

    Directory of Open Access Journals (Sweden)

    Melissa K Gregory

    Full Text Available BACKGROUND: Δ6-Desaturase (Fads2 is widely regarded as rate-limiting in the conversion of dietary α-linolenic acid (18:3n-3; ALA to the long-chain omega-3 polyunsaturated fatty acid docosahexaenoic acid (22:6n-3; DHA. However, increasing dietary ALA or the direct Fads2 product, stearidonic acid (18:4n-3; SDA, increases tissue levels of eicosapentaenoic acid (20:5n-3; EPA and docosapentaenoic acid (22:5n-3; DPA, but not DHA. These observations suggest that one or more control points must exist beyond ALA metabolism by Fads2. One possible control point is a second reaction involving Fads2 itself, since this enzyme catalyses desaturation of 24:5n-3 to 24:6n-3, as well as ALA to SDA. However, metabolism of EPA and DPA both require elongation reactions. This study examined the activities of two elongase enzymes as well as the second reaction of Fads2 in order to concentrate on the metabolism of EPA to DHA. METHODOLOGY/PRINCIPAL FINDINGS: The substrate selectivities, competitive substrate interactions and dose response curves of the rat elongases, Elovl2 and Elovl5 were determined after expression of the enzymes in yeast. The competitive substrate interactions for rat Fads2 were also examined. Rat Elovl2 was active with C(20 and C(22 polyunsaturated fatty acids and this single enzyme catalysed the sequential elongation reactions of EPA→DPA→24:5n-3. The second reaction DPA→24:5n-3 appeared to be saturated at substrate concentrations not saturating for the first reaction EPA→DPA. ALA dose-dependently inhibited Fads2 conversion of 24:5n-3 to 24:6n-3. CONCLUSIONS: The competition between ALA and 24:5n-3 for Fads2 may explain the decrease in DHA levels observed after certain intakes of dietary ALA have been exceeded. In addition, the apparent saturation of the second Elovl2 reaction, DPA→24:5n-3, provides further explanations for the accumulation of DPA when ALA, SDA or EPA is provided in the diet. This study suggests that Elovl2 will be

  17. Identification and Biological Activities of Long-Chain Peptaibols Produced by a Marine-Derived Strain of Trichoderma longibrachiatum.

    Science.gov (United States)

    Mohamed-Benkada, Mustapha; François Pouchus, Yves; Vérité, Philippe; Pagniez, Fabrice; Caroff, Nathalie; Ruiz, Nicolas

    2016-05-01

    Six long-chain peptaibols, 1 - 6, were identified from agar cultures of a marine-derived Trichoderma longibrachiatum Rifai strain (MMS151) isolated from blue mussels. The structure elucidation was carried out using electrospray ionization ion trap mass spectrometry (ESI-IT-MS) and GC/EI-MS. The long-chain peptaibols exhibited the general building scheme Ac-Aib-Ala-Aib-Ala-Aib-XXX-Gln-Aib-Vxx-Aib-Gly-XXX-Aib-Pro-Vxx-Aib-XXX-Gln-Gln-Pheol and were similar or identical to recurrent 20-residue peptaibols produced by Trichoderma spp. Three new sequences were identified and were called longibrachins A-0, A-II-a, and A-IV-b. The isolated peptaibols were assayed for cytotoxic, antibacterial, and antifungal activities, and acute toxicity on Dipteran larvae. PMID:27009018

  18. Theoretical dietary modelling of Australian seafood species to meet long-chain omega 3 fatty acid dietary recommendations

    OpenAIRE

    Jessica A. Grieger; Catherine McLeod; Lily Chan; Miller, Michelle D.

    2013-01-01

    Background: Several agencies recommend seafood to be consumed 2–3 times per week. In Australia, there is a lack of nutrient composition data for seafood species and it is not known whether including different seafood species in a diet would provide sufficient long-chain omega 3 fatty acids (LC n–3 PUFA) to meet various national recommendations. Objective: To utilise recent nutrient composition data for major Australian seafood groups (n=24) with the addition of two tuna options ...

  19. Effects of long-chain surfactants, short-chain alcohols and hydrolyzable cations on the Hydrophobic and Hydration Forces

    OpenAIRE

    Subramanian, Vivek

    1998-01-01

    Effects of Long-chain Surfactants, Short-chain Alcohols and Hydrolizable Cations on the Hydrophobic and Hydration Forces Vivek Subramanian (ABSTRACT) The DLVO theory states that the interaction between two lyophobic particles in aqueous media can be predicted by the sum of two surface forces, i.e., the electrical double-layer and van der Waals forces. This theory, which was developed 50 years ago, served as a backbone for colloid chemistry. However, various experiments co...

  20. Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans ☆

    OpenAIRE

    Vauzour, D.; Pascual-Teresa, Sonia de; Minihane, Anne-Marie

    2015-01-01

    © 2015 The Authors. Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we ...

  1. Role of perinatal long-chain omega-3 fatty acids in cortical circuit maturation: Mechanisms and implications for psychopathology

    OpenAIRE

    McNamara, Robert K; Vannest, Jennifer J.; Valentine, Christina J.

    2015-01-01

    Accumulating translational evidence suggests that the long-chain omega-3 fatty acid docosahexaenoic acid (DHA) plays a role in the maturation and stability of cortical circuits that are impaired in different recurrent psychiatric disorders. Specifically, rodent and cell culture studies find that DHA preferentially accumulates in synaptic and growth cone membranes and promotes neurite outgrowth, dendritic spine stability, and synaptogenesis. Additional evidence suggests that DHA may play a rol...

  2. Growth and development of term infants fed with milk with long-chain polyunsaturated fatty acid supplementation

    Institute of Scientific and Technical Information of China (English)

    BEN Xiao-ming 贲晓明; ZHOU Xiao-yu 周晓玉; ZHAO Wei-hua 赵卫华; YU Wen-liang 喻文亮; PAN Wei 潘伟; ZHANG Wei-li 张伟利; WU Sheng-mei 吴圣楣; Christien M. Van Beusekom; Anne Schaafsma

    2004-01-01

    @@ Presently, there is growing interest in long-chain polyunsaturated fatty acids (LCPUFAs), which are considered a major determinant of growth, visual and neural development, and long-term health.1 Two groups of LCPUFAs have received special interest: homologues of linoleic acid (LA) of the n-6 series, which are precursors of arachidonic acid (AA), and homologues of α-linolenic acid (ALA) of the n-3 series, which are precursors of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

  3. Model-Based Reactor Design in Free-Radical Polymerization with Simultaneous Long-Chain Branching and Scission

    OpenAIRE

    Hidetaka Tobita

    2015-01-01

    Polymers are the products of processes and their microstructure can be changed significantly by the reactor systems employed, especially for nonlinear polymers. The Monte Carlo simulation technique, based on the random sampling technique, is used to explore the effect of reactor types on the branched polymer structure, formed through free-radical polymerization with simultaneous long-chain branching and scission, as in the case of low-density polyethylene synthesis. As a simplified model for...

  4. Effect of sulfate on methanogenic communities that degrade unsaturated and saturated long-chain fatty acids (LCFA)

    OpenAIRE

    Sousa, D.Z.; Alves, J.I.; Alves, M. M.; Smidt, Hauke; Stams, A.J.M.

    2009-01-01

    Anaerobic bacteria involved in the degradation of long-chain fatty acids (LCFA), in the presence of sulfate as electron acceptor, were studied by combined cultivation-dependent and molecular techniques. The bacterial diversity in four mesophilic sulfate-reducing enrichment cultures, growing on oleate (C18:1, unsaturated LCFA) or palmitate (C16:0, saturated LCFA), was studied by denaturing gradient gel electrophoresis (DGGE) profiling of polymerase chain reaction (PCR)-amplified 16S rRNA gene ...

  5. Mechanism, kinetics and microbiology of inhibition caused by long-chain fatty acids in anaerobic digestion of algal biomass

    OpenAIRE

    Ma, Jingwei; Zhao, Quan-Bao; Laurens, Lieve L. M.; Jarvis, Eric E.; Nagle, Nick J.; Chen, Shulin; Frear, Craig S.

    2015-01-01

    Background Oleaginous microalgae contain a high level of lipids, which can be extracted and converted to biofuel. The lipid-extracted residue can then be further utilized through anaerobic digestion to produce biogas. However, long-chain fatty acids (LCFAs) have been identified as the main inhibitory factor on microbial activity of anaerobic consortium. In this study, the mechanism of LCFA inhibition on anaerobic digestion of whole and lipid-extracted algal biomass was investigated with a ran...

  6. Crystallization of the C-terminal domain of the mouse brain cytosolic long-chain acyl-CoA thioesterase

    International Nuclear Information System (INIS)

    The C-terminal domain of the mouse long-chain acyl-CoA thioesterase has been expressed in bacteria and crystallized by vapour diffusion. The crystals diffract to 2.4 Å resolution. The mammalian long-chain acyl-CoA thioesterase, the enzyme that catalyses the hydrolysis of acyl-CoAs to free fatty acids, contains two fused 4HBT (4-hydroxybenzoyl-CoA thioesterase) motifs. The C-terminal domain of the mouse long-chain acyl-CoA thioesterase (Acot7) has been expressed in bacteria and crystallized. The crystals were obtained by vapour diffusion using PEG 2000 MME as precipitant at pH 7.0 and 290 K. The crystals have the symmetry of space group R32 (unit-cell parameters a = b = 136.83, c = 99.82 Å, γ = 120°). Two molecules are expected in the asymmetric unit. The crystals diffract to 2.4 Å resolution using the laboratory X-ray source and are suitable for crystal structure determination

  7. Method of making alkyl esters

    Science.gov (United States)

    Elliott, Brian

    2010-09-14

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

  8. Raman and ab initio studies of simple and binary 1-alkyl-3-methylimidazolium ionic liquids

    DEFF Research Database (Denmark)

    Berg, R.W.; Deetlefs, M.; Seddon, K.R.; Shim, Irene; Thompson, J.M.

    2005-01-01

    calculations. The previously reported anti and gauche forms of the [C(4)mim](+) cation have been observed, and this study reveals this to be a general feature of the long-chain I-alkyl derivatives. Analysis of mixtures Of [C(6)mim]Cl and [C(6)mim][PF6] has provided information on the nature of the hydrogen...... bonding between the imidazolium headgroup and the anions, and the invariance of the essentially 50:50 mixture of the predominant conformers informs on the nature of glass formation in these systems....

  9. Alkyl caffeates improve the antioxidant activity, antitumor property and oxidation stability of edible oil.

    Directory of Open Access Journals (Sweden)

    Jun Wang

    Full Text Available Caffeic acid (CA is distributed widely in nature and possesses strong antioxidant activity. However, CA has lower solubility in non-polar media, which limits its application in fat-soluble food. To increase the lipophilicity of natural antioxidant CA, a series of alkyl caffeates were synthesized and their antioxidant and antitumor activities were investigated. The antioxidant parameters, including the induction period, acid value and unsaturated fatty acid content, of the alkyl caffeates in edible oil were firstly investigated. The results indicated that alkyl caffeates had a lower DPPH IC₅₀ (14-23 µM compared to CA, dibutyl hydroxy toluene (BHT and Vitamin C (24-51 µM, and significantly inhibited four human cancer cells (SW620, SW480, SGC7901 and HepG2 with inhibition ratio of 71.4-78.0% by a MTT assay. With regard to the induction period and acid value assays, methyl and butyl caffeates had higher abilities than BHT to restrain the oxidation process and improve the stability of edible oil. The addition of ethyl caffeate to oil allowed maintenance of a higher unsaturated fatty acid methyl ester content (68.53% at high temperatures. Overall, the alkyl caffeats with short chain length (n<5 assessed better oxidative stability than those with long chain length. To date, this is the first report to the correlations among the antioxidant activity, anticancer activity and oxidative stability of alkyl caffeates.

  10. Long-chain alkaenone unsaturation index as sea surface temperature proxy in southwest Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, N.S.; Pasha, S.K.G.; SriRamKrishna, M.; Shirodkar, P.V.; Yadava, M.G.; Rao, K.M.

    - soon 17 that causes surface nutrient enrichment by conve c- tive currents. As the process was more e f ficient in the glacial phase, the primary produ c tion should have been higher then. Our alkenone data conform to this trend. The alkenone... to the coatings and discrete iron - bearing phases pr e sent in clay 2,3 . Industries like ceramic, paper, paint, rubber, plastic, poly mer, cosmetics, medicine, insect i cide, pesticide, etc . widely use kaolinite clay for various purposes. Pre s ence...

  11. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  12. Anti-inflammatory coumarins with short- and long-chain hydrophobic groups from roots of Angelica dahurica cv. Hangbaizhi.

    Science.gov (United States)

    Wei, Wei; Wu, Xiu-Wen; Deng, Gai-Gai; Yang, Xiu-Wei

    2016-03-01

    The (1)H NMR-guided fractionation of a cyclohexane soluble portion of the 75% ethanolic extract of the roots of Angelica dahurica cv. Hangbaizhi led to the isolation of two coumarins, namely, 5-(3"-hydroxy-3"-methylbutyl)-8-hydroxyfuranocoumarin, and isobyakangelicin hydrate-3"-ethyl ether, and ten coumarins with short- or long-chain hydrophobic groups, namely, andafocoumarins A-J. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of the C-2" secondary alcohols in ten of these compounds were deduced via the circular dichroism data of the in situ formed [Rh2(OCOCF3)4] complex, and oxidation reactions were utilized to determine location of the double bonds in the lipid chain of andafocoumarins H and I, respectively. The long-chain hydrophobic group of andafocoumarin J was determined by the method of chemical degradation and GC-MS analysis. It was the first time that coumarins with short- or long-chain hydrophobic groups in this plant had been comprehensively investigated. All isolates were assayed for their inhibitory effect against nitric oxide (NO) production in a lipopolysaccharide (LPS)-activated RAW264.7 macrophage cell line, among which andafocoumarins A and B exhibited a potent inhibition on LPS-activated NO production with IC50 values of 19.7 and 13.9 μM, respectively, indicating their stronger inhibitory activity than l-N(6)-(1-iminoethyl)-lysine (IC50=23.7 μM), a selective inhibitor of inducible nitric oxide synthase. PMID:26775737

  13. Identification of Novel Genes Involved in Long-Chain n-Alkane Degradation by Acinetobacter sp. Strain DSM 17874▿

    Science.gov (United States)

    Throne-Holst, Mimmi; Wentzel, Alexander; Ellingsen, Trond E.; Kotlar, Hans-Kristian; Zotchev, Sergey B.

    2007-01-01

    Acinetobacter sp. strain DSM 17874 is capable of utilizing n-alkanes with chain lengths ranging from that of decane (C10H22) to that of tetracontane (C40H82) as a sole carbon source. Two genes encoding AlkB-type alkane hydroxylase homologues, designated alkMa and alkMb, have been shown to be involved in the degradation of n-alkanes with chain lengths of from 10 to 20 C atoms in this strain. Here, we describe a novel high-throughput screening method and the screening of a transposon mutant library to identify genes involved in the degradation of n-alkanes with C chain lengths longer than 20, which are solid at 30°C, the optimal growth temperature for Acinetobacter sp. strain DSM 17874. A library consisting of approximately 6,800 Acinetobacter sp. strain DSM 17874 transposon mutants was constructed and screened for mutants unable to grow on dotriacontane (C32H66) while simultaneously showing wild-type growth characteristics on shorter-chain n-alkanes. For 23 such mutants isolated, the genes inactivated by transposon insertion were identified. Targeted inactivation and complementation studies of one of these genes, designated almA and encoding a putative flavin-binding monooxygenase, confirmed its involvement in the strain's metabolism of long-chain n-alkanes. To our knowledge, almA represents the first cloned gene shown to be involved in the bacterial degradation of long-chain n-alkanes of 32 C's and longer. Genes encoding AlmA homologues were also identified in other long-chain n-alkane-degrading Acinetobacter strains. PMID:17400787

  14. The effects of n-3 long-chain polyunsaturated fatty acids on bone formation and growth factors in adolescent boys

    DEFF Research Database (Denmark)

    Damsgaard, C. T.; Mølgaard, C.; Gyldenløve, S. N.;

    2012-01-01

    NTRODUCTION: Animal studies indicate that n-3 long-chain polyunsaturated fatty acids (LCPUFAs) increase bone formation. To our knowledge, no studies have examined this in growing humans. This study investigated whether bone mass and markers of bone formation and growth were (i) associated with......-1 (IGF-1) during intervention (β = 0.24, P = 0.03, n = 78). DISCUSSION: DHA status and fish oil supplementation were not associated with bone mass or markers of bone formation in adolescent boys, but IGF-1 increased with increasing DHA status....

  15. Solubilisation of poorly water-soluble drugs during in vitro lipolysis of medium- and long-chain triacylglycerols

    DEFF Research Database (Denmark)

    Christensen, Janne Ørskov; Schultz, Kirsten; Mollgaard, Birgitte; Kristensen, Henning Gjelstrup; Mullertz, Anette

    2004-01-01

    -chain triacylglycerol (MCT) and a long-chain triacylglycerol (LCT), respectively. In general, an oil solution was used as the lipid source in the model. Samples were analysed in regard to micellar size, lipid composition and drug concentration. During lipolysis, the content of lipolytic products in the aqueous micellar...... towards higher solubilisation of LU 28-179, when it was administered in the LCT (approximately 24% released) compared to when it was administered in the MCT (approximately 15% released) at 70% hydrolysis, and a lagphase was observed. There was no difference in the solubilisation of probucol using MCT or...

  16. Surface passivation of (100) GaSb using self-assembled monolayers of long-chain octadecanethiol

    Science.gov (United States)

    Papis-Polakowska, E.; Kaniewski, J.; Jurenczyk, J.; Jasik, A.; Czuba, K.; Walkiewicz, A. E.; Szade, J.

    2016-05-01

    The passivation of (100) GaSb surface was investigated by means of the long-chain octadecanethiol (ODT) self-assembled monolayer (SAM). The properties of ODT SAM on (100) GaSb were characterized by the atomic force microscopy using Kelvin probe force microscopy mode and X-ray photoelectron spectroscopy. The chemical treatment of 10mM ODT-C2H5OH has been applied to the passivation of a type-II superlattice InAs/GaSb photodetector. The electrical measurements indicate that the current density was reduced by one order of magnitude as compared to an unpassivated photodetector.

  17. Surface passivation of (100 GaSb using self-assembled monolayers of long-chain octadecanethiol

    Directory of Open Access Journals (Sweden)

    E. Papis-Polakowska

    2016-05-01

    Full Text Available The passivation of (100 GaSb surface was investigated by means of the long-chain octadecanethiol (ODT self-assembled monolayer (SAM. The properties of ODT SAM on (100 GaSb were characterized by the atomic force microscopy using Kelvin probe force microscopy mode and X-ray photoelectron spectroscopy. The chemical treatment of 10mM ODT-C2H5OH has been applied to the passivation of a type-II superlattice InAs/GaSb photodetector. The electrical measurements indicate that the current density was reduced by one order of magnitude as compared to an unpassivated photodetector.

  18. Functional Analysis of Long-chain Acyl-CoA Synthetase 1 in 3T3-L1 Adipocytes*

    OpenAIRE

    Lobo, Sandra; Wiczer, Brian M.; Bernlohr, David A

    2009-01-01

    ACSL1 (acyl-CoA synthetase 1), the major acyl-CoA synthetase of adipocytes, has been proposed to function in adipocytes as mediating free fatty acid influx, esterification, and storage as triglyceride. To test this hypothesis, ACSL1 was stably silenced (knockdown (kd)) in 3T3-L1 cells, differentiated into adipocytes, and evaluated for changes in lipid metabolism. Surprisingly, ACSL1-silenced adipocytes exhibited no significant changes in basal or insulin-stimulated long-chain fatty acid uptak...

  19. The impact of long chain polyunsaturated fatty acids on food allergy and cardiovascular disease. Fish and no chips?

    OpenAIRE

    van den Elsen, L.W.J.

    2013-01-01

    This thesis creates more insight into the efficacy and mechanism of action of polyunsaturated fatty acids (PUFA), which act on the interface between pharmacology and nutrition in the prevention of allergic and cardiovascular disease. PUFA are categorized into n-6 and n-3 PUFA. The last decades have seen a fall in the consumption of long chain n-3 PUFA (LCPUFA) from oily fish, while the use of vegetable oils and products that are rich in n-6 PUFA has increased. It was demonstrated that increas...

  20. Rheological properties of long-chain branched chlorinated poly(isobutylene-co-isoprene)-graft-polybutadiene terpolymers (CIIR-g-BR)

    Science.gov (United States)

    Sendorek, Jerzy (George)

    Anionically polymerized "living" polybutadiene (BR) was grafted onto chlorinated poly(isobutylene-co-isoprene) (CIIR) to form a series of elastomeric graft copolymers (CIIR-g-BR) of comb-type, long-chain branching structure (LCB) with systematically varying length and number of branches. A comprehensive program of analytical characterization of the structure and morphology of these materials using SEC/DRI-DV, NMR, FT-IR, DSC, TGA, TEM and other techniques, was designed to determine all relevant structural variables and parameters, as well as to exclude the presence of the potential compositional interferences (gel, residual solvent, unattached branch parent polymer, etc.) for intended correlations between branching structure and rheological properties. The principal branching characteristics of comb-like long-chain branched structures were derived from the stoichiometry of the grafting reaction, confirmed by compositional analysis using a combination of NMR/FT-IR/SEC and supplemented by SEC characterization of the parent linear polymers constituting the backbone (CIIR) and the branch of the graft (BR), respectively. Linear viscoelastic properties of these materials were determined by a Rheometrics Mechanical Spectrometer (RMS-800) using small amplitude, dynamic (sinusoidal oscillatory) shear. These measurements were supplemented by Rubber Process Analyzer (RPA 2000sp{TM}) testing in a comparable range of strain amplitudes, frequencies and temperatures. Stress relaxation experiments, following small amplitude step-strain in shear, complemented the dynamic mechanical measurement. Non-linear viscoelastic properties in shear were investigated in a series of isothermal strain and frequency sweeps using large strain (up to 800%) oscillations (RPA 2000), and by stress following a large-amplitude (˜75%) step shear strain, using the Dynamic Stress Relaxometer (DSR). An insight into the morphology of the grafts by means of the TEM and DSC has been compared to the results of

  1. FAT/CD36-mediated Long-Chain Fatty Acid Uptake in Adipocytes Requires Plasma Membrane Rafts

    OpenAIRE

    Pohl, Jürgen; Ring, Axel; Korkmaz, Ümine; Ehehalt, Robert; Stremmel, Wolfgang

    2005-01-01

    We previously reported that lipid rafts are involved in long-chain fatty acid (LCFA) uptake in 3T3-L1 adipocytes. The present data show that LCFA uptake does not depend on caveolae endocytosis because expression of a dominant negative mutant of dynamin had no effect on uptake of [3H]oleic acid, whereas it effectively prevented endocytosis of cholera toxin. Isolation of detergent-resistant membranes (DRMs) from 3T3-L1 cell homogenates revealed that FAT/CD36 was expressed in both DRMs and deter...

  2. Determination of essential fatty acids and long chain polyunsaturated fatty acids in complimentary infant foods in the UK

    OpenAIRE

    Loughrill, Emma; Zand, Nazanin

    2014-01-01

    The study reported herein was conducted to establish the concentration of two essential fatty acids; linoleic acid (LA) 18:2 n-6 and α-linolenic acid (ALA) 18:3 n-3; and three long chain poly unsaturated fatty acids (LCPUFA); eicosapentaenoic acid (EPA) 20:5 n-3, decosahexaenoic acid (DHA) 22:6 n-3 and arachidonic acid (AA) 20:4 n-6 in fish based commercial infant foods in the UK. Quantitative analyses were conducted on four different products using charged aerosol detection HPLC. The total ...

  3. Perfluorinated Alkyl Substances

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Clapp, Richard

    2015-01-01

    Perfluorinated alkyl substances have been in use for over sixty years. These highly stable substances were at first thought to be virtually inert and of low toxicity. Toxicity information slowly emerged on perfluorooctanoic acid and perfluorooctane sulfonate. More than thirty years ago, early...... studies reported immunotoxicity and carcinogenicity effects. The substances were discovered in blood samples from exposed workers, then in the general population and in community water supplies near U.S. manufacturing plants. Only recently has research publication on perfluorooctanoic acid and...... perfluorooctane sulfonate intensified. While the toxicology database is still far from complete, carcinogenicity and immunotoxicity now appear to be relevant risks at prevalent exposure levels. Existing drinking water limits are based on less complete evidence that was available before 2008 and may be more than...

  4. 1H NMR analysis of long-chain-branched strong polyelectrolytes obtained by vinyl/divinyl monomer copolymerization in aqueous medium

    Czech Academy of Sciences Publication Activity Database

    Podešva, Jiří; Spěváček, Jiří; Kratochvíl, Pavel; Netopilík, Miloš

    2013-01-01

    Roč. 18, č. 7 (2013), s. 557-565. ISSN 1023-666X Institutional support: RVO:61389013 Keywords : long-chain branching * NMR * polyelectrolytes Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.487, year: 2013

  5. Long-chain bases of sphingolipids are transported into cells via the acyl-CoA synthetases.

    Science.gov (United States)

    Narita, Tomomi; Naganuma, Tatsuro; Sase, Yurie; Kihara, Akio

    2016-01-01

    Transport of dietary lipids into small-intestinal epithelial cells is pathologically and nutritionally important. However, lipid uptake remains an almost unexplored research area. Although we know that long-chain bases (LCBs), constituents of sphingolipids, can enter into cells efficiently, the molecular mechanism of LCB uptake is completely unclear. Here, we found that the yeast acyl-CoA synthetases (ACSs) Faa1 and Faa4 are redundantly involved in LCB uptake. In addition to fatty acid-activating activity, transporter activity toward long-chain fatty acids (LCFAs) has been suggested for ACSs. Both LCB and LCFA transports were largely impaired in faa1Δ faa4Δ cells. Furthermore, LCB and LCFA uptakes were mutually competitive. However, the energy dependency was different for their transports. Sodium azide/2-deoxy-D-glucose treatment inhibited import of LCFA but not that of LCB. Furthermore, the ATP-AMP motif mutation FAA1 S271A largely impaired the metabolic activity and LCFA uptake, while leaving LCB import unaffected. These results indicate that only LCFA transport requires ATP. Since ACSs do not metabolize LCBs as substrates, Faa1 and Faa4 are likely directly involved in LCB transport. Furthermore, we revealed that ACSs are also involved in LCB transport in mammalian cells. Thus, our findings provide strong support for the hypothesis that ACSs directly transport LCFAs. PMID:27136724

  6. A novel high-performance thin layer chromatography method for quantification of long chain aliphatic hydrocarbons from Cissus quadrangularis

    Directory of Open Access Journals (Sweden)

    Vandana Jain

    2016-08-01

    Full Text Available Context: A high-performance thin layer chromatography (HPTLC is an analytical technique, which can be used for the determination of constituents or marker components in various parts of the plants. Earlier studies have estimated phytoconstituents from the stem and other aerial plant parts of Cissus quadrangularis Linn. Estimation of hydrocarbons can also be successfully done using HPTLC technique using suitable derivatization. Aims: To develop and validate a simple and rapid method for the estimation of long chain aliphatic hydrocarbons from the leaves of C. quadrangularis using HPTLC technique. Methods: Precoated silica gel 60 F254 plates were used as stationary phase. The mobile phase used was hexane (100 %. The detection of spots was carried out using berberine sulphate as detecting reagent. Results: The method was validated in terms of linearity, sensitivity, accuracy, and precision. Linearity range was found to be 2-10 µg/mL, limit of detection 0.127 µg/mL, and limit of quantification 0.384 µg/mL. Conclusions: A novel, simple, accurate, precise and sensitive HPTLC method has been developed and validated for the estimation of long chain aliphatic hydrocarbons obtained from the leaves of C. quadrangularis Linn.

  7. A new LC-ESI-MS/MS method to measure long-chain acylcarnitine levels in cultured cells

    International Nuclear Information System (INIS)

    The quantitative evaluation of long-chain acylcarnitines in lipid extracts from cultured cells or tissues is a prerequisite to study carnitine palmitoyltransferase (CPT) activity. There is thus a need for the accurate measurement of the concentration of long-chain acylcarnitines at the lowest concentration present in lipid extracts. Here we report a fast and reliable quantitative method based on the use of weak acid extraction and liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to quantify acylcarnitines through hydrophilic interaction chromatography. The method was validated using isotopic dilution and the results allow the analysis of a large number of samples at low concentration levels (down to 0.35 nmol L-1 for palmitoylcarnitine) with good inter- and intra-day precision. The method was used for the quantitative study of changes in concentration of palmitoylcarnitine and other acylcarnitines in PC-12 cells over-expressing CPT1a gene. It was also used to measure CPT1 activity in mitochondria isolated from transfected cells, giving similar results to the more common radiometric method, but with higher sensitivity

  8. Acetylcholinesterase(AChE)-catalyzed hydrolysis of long-chain thiocholine esters:shift to a new chemical mechanism

    International Nuclear Information System (INIS)

    The kinetic and chemical mechanisms of AChE-catalyzed hydrolysis of short-chain thiocholine esters are relatively well documented. Up to propanoylthiocholine (PrTCh) the chemical mechanism is general acid-base catalysis by the active site catalytic triad. The chemical mechanism for the enzyme-catalyzed butyrylthio-choline(BuTCh) hydrolysis shifts to a parallel mechanism in which general base catalysis by E199 of direct water attack to the carbonyl carbon of the substrate. (Selwood, T., et al. J. Am. Chem. Soc. 1993, 115, 10477-10482) The long chain thiocholine esters such as hexanoylthiocholine (HexTCh), heptanoylthiocholine (HepTCh), and octanoylthiocholine (OcTCh) are hydrolyzed by electric eel acetylcholinesterase (AChE). The kinetic parameters are determined to show that these compounds have a lower Michaelis constant than BuTCh and the pH-Rate profile showed that the mechanism is similar to that of BuTCh hydrolysis. The solvent isotope effect and proton inventory of AChE-catalyzed hydrolysis of HexTCh showed that one proton transfer is involved in the transition state of the acylation stage. The relationship between the dipole moment and the Michaelis constant of the long chain thiocholine esters showed that the dipole moment is the most important factor for the binding of a substrate to the enzyme active site

  9. Acetylcholinesterase(AChE)-catalyzed hydrolysis of long-chain thiocholine esters:shift to a new chemical mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Dai Il; Shin, Young Ju [Donga Univ., Busan (Korea, Republic of); Lee, Eun Seok; Lee, Bong Ho [Hanbat National Univ., Daejon (Korea, Republic of); Moon, Tae Sung; Yoon, Chang No [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2003-01-01

    The kinetic and chemical mechanisms of AChE-catalyzed hydrolysis of short-chain thiocholine esters are relatively well documented. Up to propanoylthiocholine (PrTCh) the chemical mechanism is general acid-base catalysis by the active site catalytic triad. The chemical mechanism for the enzyme-catalyzed butyrylthio-choline(BuTCh) hydrolysis shifts to a parallel mechanism in which general base catalysis by E199 of direct water attack to the carbonyl carbon of the substrate. (Selwood, T., et al. J. Am. Chem. Soc. 1993, 115, 10477-10482) The long chain thiocholine esters such as hexanoylthiocholine (HexTCh), heptanoylthiocholine (HepTCh), and octanoylthiocholine (OcTCh) are hydrolyzed by electric eel acetylcholinesterase (AChE). The kinetic parameters are determined to show that these compounds have a lower Michaelis constant than BuTCh and the pH-Rate profile showed that the mechanism is similar to that of BuTCh hydrolysis. The solvent isotope effect and proton inventory of AChE-catalyzed hydrolysis of HexTCh showed that one proton transfer is involved in the transition state of the acylation stage. The relationship between the dipole moment and the Michaelis constant of the long chain thiocholine esters showed that the dipole moment is the most important factor for the binding of a substrate to the enzyme active site.

  10. A new LC-ESI-MS/MS method to measure long-chain acylcarnitine levels in cultured cells

    Energy Technology Data Exchange (ETDEWEB)

    Jauregui, Olga [Scientific and Technical Services, University of Barcelona (Spain); Sierra, Adriana Y.; Carrasco, Patricia; Gratacos, Esther [Molecular and Cellular Unit, School of Health Sciences, International University of Catalonia (Spain); Hegardt, Fausto G. [Department of Biochemistry and Molecular Biology, University of Barcelona, School of Pharmacy (Spain); Casals, Nuria [Molecular and Cellular Unit, School of Health Sciences, International University of Catalonia (Spain)], E-mail: ncasals@csc.uic.es

    2007-09-05

    The quantitative evaluation of long-chain acylcarnitines in lipid extracts from cultured cells or tissues is a prerequisite to study carnitine palmitoyltransferase (CPT) activity. There is thus a need for the accurate measurement of the concentration of long-chain acylcarnitines at the lowest concentration present in lipid extracts. Here we report a fast and reliable quantitative method based on the use of weak acid extraction and liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to quantify acylcarnitines through hydrophilic interaction chromatography. The method was validated using isotopic dilution and the results allow the analysis of a large number of samples at low concentration levels (down to 0.35 nmol L{sup -1} for palmitoylcarnitine) with good inter- and intra-day precision. The method was used for the quantitative study of changes in concentration of palmitoylcarnitine and other acylcarnitines in PC-12 cells over-expressing CPT1a gene. It was also used to measure CPT1 activity in mitochondria isolated from transfected cells, giving similar results to the more common radiometric method, but with higher sensitivity.

  11. Inhibition of phorbol ester-induced differentiation of HL-60 cells by long-chain (sphingoid) bases

    International Nuclear Information System (INIS)

    HL-60 cells incubated with low concentrations of sphinganine failed to attach to petri dishes when treated for 24h with phorbol 12-myristate 13-acetate (PMA) of dioctanoylglycerol, which induce differentiation of these cells to adherent macrophages via activation of protein kinase C. PMA-dependent adherence was inhibited 50% by 3 μM sphinganine or 1 μM sphingosine. Sphinganine also blocked the inhibition of cell growth that occurs in response to PMA. These effects were not due to loss of cell viability, although higher concentrations were toxic. The effects were less apparent after 3 d, when considerable metabolism of [3-3H]sphinganine had occurred. Other long-chain bases (e.g., stearylamine) were also inhibitory, but octylamine, N-acetylsphinganine and ceramides had no effect at similar concentrations. Sphinganine also decreased the binding of [3H]phorbol dibutyrate by the phorbol receptor of HL-60 cells, protein kinase C. These results establish that long chain (sphingoid) bases inhibit protein kinase C in HL-60 cells and may function physiologically as negative effectors of this enzyme

  12. Substrate availability for long-chain base formation as a regulator of hepatic sphingolipid and cholesterol biosynthesis

    International Nuclear Information System (INIS)

    The de novo biosynthesis of the sphinganine and sphingosine backbones of sphingolipids was studied with isolated rat hepatocytes and established liver cell lines. The rate of incorporation of radiolabel from [14C]-serine by intact cells was half maximal at 0.3 mM, which is similar to the K/sub m/ of the initial enzyme of this pathway and in vivo concentrations of this substrate. Long-chain base biosynthesis was stimulated by another precursor, palmitic acid, but other fatty acids were inhibitory. Hepatocytes isolated from fed and fasted rats had different rates of sphingolipid formation, which may also reflect the relative levels of palmitoyl-CoA. These results established that the availability of the precursors of long-chain base formation, serine and palmitic acid, is a major factor in the regulation of this pathway. Since sphingomyelin biosynthesis could be modified, its relationship to cholesterol metabolism was also examined. Both hepatocytes and cultured liver cells in high serine (0.6mM) had increased incorporation of [14C]-acetate into cholesterol (13%, P < 0.05 and 50%, P < 0.01, respectively). These results indicate that sphingolipid and cholesterol biosynthesis are coordinately regulated, perhaps because these lipids are located in similar membranes and lipoproteins

  13. Long-chain polyunsaturated fatty acid biosynthesis in chordates: Insights into the evolution of Fads and Elovl gene repertoire.

    Science.gov (United States)

    Castro, L Filipe C; Tocher, Douglas R; Monroig, Oscar

    2016-04-01

    Long-chain polyunsaturated fatty acids (LC-PUFA) are major components of complex lipid molecules and are also involved in numerous critical biological processes. Studies conducted mainly in vertebrates have demonstrated that LC-PUFA can be biosynthesized through the concerted action of two sets of enzymes, namely fatty acyl desaturases (Fads) and elongation of very long-chain fatty acid (Elovl) proteins. While LC-PUFA research is a thriving field, mainly focused on human health, an integrated view regarding the evolution of LC-PUFA biosynthetic genetic machinery in chordates is yet to be produced. Particularly important is to understand whether lineage specific life history trajectories, as well as major biological transitions, or particular genomic processes such as genome duplications have impacted the evolution of LC-PUFA biosynthetic pathways. Here we review the gene repertoire of Fads and Elovl in chordate genomes and the diversity of substrate specificities acquired during evolution. We take advantage of the magnitude of genomic and functional data to show that combination duplication processes and functional plasticity have generated a wide diversity of physiological capacities in extant lineages. A clear evolutionary framework is provided, which will be instrumental for the full clarification of functional capacities between the various vertebrate groups. PMID:26769304

  14. Intake levels of dietary long-chain PUFAs modify the association between genetic variation in FADS and LDL-C.

    Science.gov (United States)

    Hellstrand, S; Sonestedt, E; Ericson, U; Gullberg, B; Wirfält, E; Hedblad, B; Orho-Melander, M

    2012-06-01

    Polymorphisms of the FA desaturase (FADS) gene cluster have been associated with LDL, HDL, and triglyceride concentrations. Because FADS converts α-linolenic acid (ALA) and linoleic acid into PUFAs, we investigated the interaction between different PUFA intakes and the FADS polymorphism rs174547 (T>C) on fasting blood lipid and lipoprotein concentrations. We included 4,635 individuals (60% females, 45-68 years) from the Swedish population-based Malmö Diet and Cancer cohort. Dietary intakes were assessed by a modified diet history method including 7-day registration of cooked meals. The C-allele of rs174547 was associated with lower LDL concentration (P = 0.03). We observed significant interaction between rs174547 and long-chain ω-3 PUFA intakes on LDL (P = 0.01); the C-allele was only associated with lower LDL among individuals in the lowest tertile of long-chain ω-3 PUFA intakes (P FADS on LDL and HDL. PMID:22451038

  15. Very-long-chain fatty acid biosynthesis is inhibited by cafenstrole, N,N-diethyl-3-mesitylsulfonyl-1H-1,2,4-triazole-1-carboxamide and its analogs

    International Nuclear Information System (INIS)

    The rice herbicide cafenstrole and its analogs inhibited the incorporation of [1-14C]-oleate and [2-14C]-malonate into very-long-chain fatty acids (VLCFAs), using Scenedesmus cells and leek microsomes from Allium porrum. Although the precise mode of interaction of cafenstrole at the molecular level is not completely clarified by the present study, it is concluded that cafenstrole acts as a specific inhibitor of the microsomal elongase enzyme involved in the biosynthesis of fatty acids with alkyl chains longer than C18. For a strong VLCFA biosynthesis inhibition an -SO2- linkage of the 1,2,4-triazole-1-carboxamides was required. Furthermore, N,N-dialkyl substitution of the carbamoyl nitrogen and electron-donating groups such as methyl at the benzene ring of 1,2,4-triazole-1-carboxamides produced a strong inhibition of VLCFA formation. A correlation was found between the phytotoxic effect against barnyardgrass (Echinochloa oryzicola) and impaired VLCFA formation. (orig.)

  16. Mild Catalytic methods for Alkyl-Alkyl Bond Formation

    Energy Technology Data Exchange (ETDEWEB)

    Vicic, David A

    2009-08-10

    Overview of Research Goals and Accomplishments for the Period 07/01/06 – 06/30/07: Our overall research goal is to transform the rapidly emerging synthetic chemistry involving alkyl-alkyl cross-couplings into more of a mechanism-based field so that that new, rationally-designed catalysts can be performed under energy efficient conditions. Our specific objectives for the previous year were 1) to obtain a proper electronic description of an active catalyst for alkyl-alkyl cross-coupling reactions and 2) to determine the effect of ligand structure on the rate, scope, selectivity, and functional group compatibility of C(sp3)-C(sp3) cross-coupling catalysis. We have completed both of these initial objectives and established a firm base for further studies. The specific significant achievements of the current grant period include: 1) we have performed magnetic and computational studies on (terpyridine)NiMe, an active catalyst for alkyl-alkyl cross couplings, and have discovered that the unpaired electron resides heavily on the terpyridine ligand and that the proper electronic description of this nickel complex is a Ni(II)-methyl cation bound to a reduced terpyridine ligand; 2) we have for the first time shown that alkyl halide reduction by terpyridyl nickel catalysts is substantially ligand based; 3) we have shown by isotopic labeling studies that the active catalyst (terpyridine)NiMe is not produced via a mechanism that involves the formation of methyl radicals when (TMEDA)NiMe2 is used as the catalyst precursor; 4) we have performed an extensive ligand survey for the alkyl-alkyl cross-coupling reactions and have found that electronic factors only moderately influence reactivity in the terpyridine-based catalysis and that the most dramatic effects arise from steric and solubility factors; 5) we have found that the use of bis(dialkylphosphino)methanes as ligands for nickel does not produce active catalysts for cross-coupling but rather leads to bridging hydride

  17. Dielectric studies of hydrogen bonded complexes tri-n-butyl phosphate (TBP) with long-chain aliphatic alcohols

    International Nuclear Information System (INIS)

    The mechanism of dipolar complexation involving TBP and three long chain aliphatic alcohols namely 1-hexanol, 1-heptanol, 1-octanol in a non-polar medium (benzene) was investigated from dielectric measurements at frequency 455 kHz and at temperature 303.16 K using modified Palit's method. The dipole moment of the complex (μbc), interaction dipole moment (Δμ), dipole moment of the H-bonded bridge (μ*) and induced polarization (ΔP) for the thermodynamically most favoured geometry of 1:1 complexes of these systems were computed. The results shows that complexation is due to partial proton transfer in all the cases studied and the tendency of complex formation is maximum in 1-heptanol system. (author)

  18. Atlantic salmon require long-chain n-3 fatty acids for optimal growth throughout the seawater period

    OpenAIRE

    Rosenlund, Grethe; Torstensen, Bente E.; Stubhaug, Ingunn; Usman, Nafiha; Sissener, Nini H.

    2016-01-01

    The nutritional requirement for n-3 long-chain PUFA in fast-growing Atlantic salmon (Salmo salar) during grow out in the sea is not well documented. Diets were formulated with levels of EPA (20 : 5n-3) and DHA (22 : 6n-3) ranging from 1·3 to 7·4 % of fatty acids (4–24 g/kg feed). Two long-term trials were conducted through the seawater phase, the first at 6 and 12°C, and the second at 12°C. In the first trial, growth at both temperatures was significantly lower in fish fed 1·4 % EPA+DHA of to...

  19. Atlantic salmon (Salmo salar L.) as a net producer of long-chain marine ω-3 fatty acids.

    Science.gov (United States)

    Sanden, Monica; Stubhaug, Ingunn; Berntssen, Marc H G; Lie, Øyvind; Torstensen, Bente E

    2011-12-14

    The objective of the present study was to investigate the effects of replacing high levels of marine ingredients with vegetable raw materials and with emphasis on lipid metabolism and net production of long-chain polyunsaturated ω-3 fatty acids (EPA + DHA). Atlantic salmon were fed three different replacement vegetable diets and one control marine diet before sensory attributes, β-oxidation capacity, and fatty acid productive value (FAPV) of ingested fatty acids (FAs) were evaluated. Fish fed the high replacement diet had a net production of 0.8 g of DHA and a FAPV of 142%. Fish fed the marine diet had a net loss of DHA. The present work shows that Atlantic salmon can be a net producer of marine DHA when dietary fish oil is replaced by vegetable oil with minor effects on sensory attributes and lipid metabolism. PMID:22017199

  20. A novel role for central ACBP/DBI as a regulator of long-chain fatty acid metabolism in astrocytes

    DEFF Research Database (Denmark)

    Bouyakdan, Khalil; Taïb, Bouchra; Budry, Lionel;

    2015-01-01

    Diazepam-Binding Inhibitor, a secreted peptide acting as an allosteric modulator of the GABAA receptor. However, its role in central LCFA metabolism remains unknown. In the present study, we investigated ACBP cellular expression, ACBP regulation of LCFA intracellular metabolism, FA profile, and FA......Acyl-CoA-binding protein (ACBP) is a ubiquitously expressed protein that binds intracellular acyl-CoA esters. Several studies have suggested that ACBP acts as an acyl-CoA pool former and regulates long-chain fatty acids (LCFA) metabolism in peripheral tissues. In the brain, ACBP is known as...... response to palmitate in hypothalamic astrocytes. Collectively, these findings reveal for the first time that central ACBP acts as a regulator of LCFA intracellular metabolism in astrocytes. Acyl-CoA-binding protein (ACBP) or diazepam-binding inhibitor is a secreted peptide acting centrally as a GABAA...

  1. Climate warming is predicted to reduce omega-3, long-chain, polyunsaturated fatty acid production in phytoplankton.

    Science.gov (United States)

    Hixson, Stefanie M; Arts, Michael T

    2016-08-01

    Phytoplankton are the main source of energy and omega-3 (n-3) long-chain essential fatty acids (EFA) in aquatic ecosystems. Their growth and biochemical composition are affected by surrounding environmental conditions, including temperature, which continues to increase as a result of climate warming. Increasing water temperatures may negatively impact the production of EFA by phytoplankton through the process of homeoviscous adaptation. To investigate this, we conducted an exploratory data synthesis with 952 fatty acid (FA) profiles from six major groups of marine and freshwater phytoplankton. Temperature was strongly correlated with a decrease in the proportion of n-3 long-chain polyunsaturated FA (LC-PUFA) and an increase in omega-6 FA and saturated FA. Based on linear regression models, we predict that global n-3 LC-PUFA production will be reduced by 8.2% for eicosapentaenoic acid (EPA) and 27.8% for docosahexaenoic acid (DHA) with an increase in water temperature of 2.5 °C. Using a previously published estimate of the global production of EPA by diatoms, which contribute to most of the world's supply of EPA, we predict a loss of 14.2 Mt of EPA annually as a result of ocean warming. The n-3 LC-PUFA are vitally important for an array of key physiological functions in aquatic and terrestrial organisms, and these FA are mainly produced by phytoplankton. Therefore, reduced production of these EFA, as a consequence of climate warming, is predicted to negatively affect species that depend on these compounds for optimum physiological function. Such profound changes in the biochemical composition of phytoplankton cell membranes can lead to cascading effects throughout the world's ecosystems. PMID:27070119

  2. Human serum-derived hydroxy long-chain fatty acids exhibit anti-inflammatory and anti-proliferative activity

    Directory of Open Access Journals (Sweden)

    Ahiahonu Pearson

    2011-05-01

    Full Text Available Abstract Background Circulating levels of novel long-chain hydroxy fatty acids (called GTAs were recently discovered in the serum of healthy subjects which were shown to be reduced in subjects with colorectal cancer (CRC, independent of tumor burden or disease stage. The levels of GTAs were subsequently observed to exhibit an inverse association with age in the general population. The current work investigates the biological activity of these fatty acids by evaluating the effects of enriched human serum extracts on cell growth and inflammation. Methods GTAs were extracted from commercially available bulk human serum and then chromatographically separated into enriched (GTA-positive and depleted (GTA-negative fractions. SW620, MCF7 and LPS stimulated RAW264.7 cells were treated with various concentrations of the GTA-positive and GTA-negative extracts, and the effects on cell growth and inflammation determined. Results Enriched fractions resulted in poly-ADP ribose polymerase (PARP cleavage, suppression of NFκB, induction of IκBα, and reduction in NOS2 mRNA transcript levels. In RAW264.7 mouse macrophage cells, incubation with enriched fractions prior to treatment with LPS blocked the induction of several pro-inflammatory markers including nitric oxide, TNFα, IL-1β, NOS2 and COX2. Conclusions Our results show that human serum extracts enriched with endogenous long-chain hydroxy fatty acids possess anti-inflammatory and anti-proliferative activity. These findings support a hypothesis that the reduction of these metabolites with age may result in a compromised ability to defend against uncontrolled cell growth and inflammation, and could therefore represent a significant risk for the development of CRC.

  3. Systematic investigations on the biodegradation and viscosity reduction of long chain hydrocarbons using Pseudomonas aeruginosa and Pseudomonas fluorescens.

    Science.gov (United States)

    Sakthipriya, N; Doble, Mukesh; Sangwai, Jitendra S

    2016-03-01

    The use of microorganisms has been researched extensively for possible applications related to hydrocarbon degradation in the petroleum industry. However, attempts to improve the effect of microorganisms on the viscosity of hydrocarbons, which find potential use in the development of robust models for biodegradation, have been rarely documented. This study investigates the degradation of long chain hydrocarbons, such as hexadecane and eicosane using Pseudomonas fluorescens PMMD3 (P. fluorescens) and Pseudomonas aeruginosa CPCL (P. aeruginosa). P. aeruginosa used here is isolated from petroleum contaminated sediments and the P. fluorescens is from the coastal area, and both have hydrocarbon degrading genes. The degradation of hydrocarbons is studied using carbon profiling and reduction in viscosity pre- and post-degradation of hydrocarbons. The carbon profiling has been obtained using gas chromatography-mass spectroscopy (GC-MS), and Fourier transform infrared spectrometer (FTIR) results. GC-MS results have indicated an improved biodegradation of hydrocarbons by 77-93% in one day. The yield coefficients of biomass (YX/S) for P. aeruginosa and P. fluorescens using hexadecane as a carbon source are 1.35 and 0.81 g g(-1), and the corresponding values with eicosane are 0.84 and 0.88 g g(-1). The viscosity of hexadecane is reduced by the order of 53 and 47%, while that of eicosane was reduced by 53 and 65%, using P. aeruginosa and P. fluorescens, respectively. This study also presents information on the activity of enzymes responsible for the hydrocarbon degradation. Pseudomonas species have shown their use in potential applications for bioremediation, oil-spill treatment, and flow assurance. We believe that this study will also provide stringent tests for possible model development for the bioremediation of long chain paraffins suitable for oilfield applications. PMID:26875795

  4. Journal bearing

    Science.gov (United States)

    Menke, John R.; Boeker, Gilbert F.

    1976-05-11

    1. An improved journal bearing comprising in combination a non-rotatable cylindrical bearing member having a first bearing surface, a rotatable cylindrical bearing member having a confronting second bearing surface having a plurality of bearing elements, a source of lubricant adjacent said bearing elements for supplying lubricant thereto, each bearing element consisting of a pair of elongated relatively shallowly depressed surfaces lying in a cylindrical surface co-axial with the non-depressed surface and diverging from one another in the direction of rotation and obliquely arranged with respect to the axis of rotation of said rotatable member to cause a flow of lubricant longitudinally along said depressed surfaces from their distal ends toward their proximal ends as said bearing members are rotated relative to one another, each depressed surface subtending a radial angle of less than 360.degree., and means for rotating said rotatable bearing member to cause the lubricant to flow across and along said depressed surfaces, the flow of lubricant being impeded by the non-depressed portions of said second bearing surface to cause an increase in the lubricant pressure.

  5. Application of long-chain aikenones and U37k values for paleotemperature estimation in the Arctic Chukchi Sea- Bering Sea area

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    -Long-chain alkenones were detected in samples of sea surface sediments from the Chukchi Sea and the Bering Sea areas, the Arctic Pole. The analysis result indicates that C37:3 methylketone is pre dominate in the long-chain alkenones from the Chukchi and Bering Sea sediments. The abundance of C37to C39 unsaturated alkenones changes in an order of C37 >C38 >C39. Based on ∑37/∑38 ratio, the de tected organism precursors of the long-chain alkenones are mainly coccolithophrid (Emiliania huxleyi).By the calibration relationship between U3k7 and U37k indices, the sea surface paleotemperature in these seas is estimated. The estimated values of U37k vary from 4.147℃ to 5. 706℃, with a mean value of 5.092℃.

  6. A biological source of oceanic alkyl nitrates

    Science.gov (United States)

    Dahl, E. E.; Lewis, C. B.; Velasco, F. L.; Escobar, C.; Kellogg, D.; Velcamp, M.

    2013-12-01

    Alkyl nitrates are an important component of reactive nitrogen in the troposphere. The oceans are a source of alkyl nitrates to the atmosphere, however the source of alkyl nitrates in the oceans is unknown. It has been demonstrated that the reaction of alkyl peroxy radicals (ROO) with nitric oxide (NO) produces alkyl nitrates in the aqueous phase. We hypothesize that alkyl nitrates may be formed by organisms through the same reaction and therefore biological production could be a source of alkyl nitrates to the troposphere. This work focuses on the production of alkyl nitrates by the diatoms Chaetoceros muelleri and Thalassiosira weisfloggi. Using chemostats, we measure alkyl nitrates formed under nitrate limited conditions. We also use triggers and inhibitors of nitric oxide formation to determine if alkyl nitrate formation is affected by changes in NO production. To date, the rates of production of alkyl nitrates in our cultures, lead us to estimate a production rate on the order of femtomolar/day for C1-C3 alkyl nitrates by diatom species in the equatorial Pacific Ocean. This suggests that diatoms may contribute to the overall ocean source of alkyl nitrates; however, it is possible that other types of phytoplankton, such as cyanobacteria, that are more abundant in the open ocean, may contribute to a greater extent.

  7. Development of bioreporter assays for the detection of bioavailability of long chain alkanes based on the marine bacterium Alcanivorax borkumensis strain SK2

    OpenAIRE

    Kumari, Rekha; Tecon, Robin; Beggah, Siham; Rutler, Rebecca; Arey, J. Samuel; van der Meer, Jan Roelof

    2011-01-01

    Long-chain alkanes are a major component of crude oil and therefore potentially good indicators of hydrocarbon spills. Here we present a set of new bacterial bioreporters and assays that allow to detect long-chain alkanes. These reporters are based on the regulatory protein AlkS and the alkB1 promoter from Alcanivorax borkumensis SK2, a widespread alkane degrader in marine habitats. Escherichia coli cells with the reporter construct reacted strongly to octane in short-term (6 h) aqueous suspe...

  8. Pregnancy duration and the ratio of long-chain n-3 fatty acids to arachidonic acid in erythrocytes from Faroese women

    DEFF Research Database (Denmark)

    Olsen, S.F.; Hansen, Harald S.; Jensen, B.;

    1989-01-01

    Dietary long-chain n-3 fatty acids (FA) may prolong gestation by inhibiting formation of prostaglandins from arachidonic acid. FA were quantified in phosphatidylcholine (PC), phosphatidylethanolamine (PE), and total lipids (TL) of red cells sampled during pregnancy from 29 Faroese women. The ratio...... of long-chain n-3 FA to arachidonic acid (the (3/6) ratio) was used as the most relevant single measure of exposure. In 18 women with certain gestational age and with spontaneous onset of delivery, gestational age was significantly associated with the (3/6) ratio quantified in PC (correlation...

  9. Influence of an n-3 long-chain polyunsaturated fatty acid-enriched diet on experimentally induced synovitis in horses.

    Science.gov (United States)

    Ross-Jones, T N; McIlwraith, C W; Kisiday, J D; Hess, T M; Hansen, D K; Black, J

    2016-06-01

    Dietary n-3 long-chain polyunsaturated fatty acid (LCPUFA) supplementation has previously been shown to modify joint-related inflammation in several species, although information in the horse is lacking. We investigated whether dietary supplementation with n-3 LCPUFA would modify experimentally induced synovitis in horses. Twelve, skeletally mature, non-pregnant mares were randomly assigned to either a control diet (CONT) or an n-3 long-chain fatty acid-enriched treatment diet (N3FA) containing 40 g/day of n-3 LCPUFA for 91 days. Blood samples taken on days 0, 30, 60 and 90, and synovial fluid collected on days 0 and 90 were processed for lipid composition. On day 91, joint inflammation was stimulated using an intra-articular (IA) injection of 100 ng of recombinant equine IL-1beta (reIL-1β). Synovial fluid samples taken at post-injection hours (PIH) 0, 4, 8 and 24 were analysed for prostaglandin E2 (PGE2 ), matrix metalloproteinase (MMP) activity and routine cytology. Synovium and articular cartilage samples collected at PIH 8 were analysed for gene expression of MMP 1 and MMP 13, interleukin-1beta (IL-1β), cyclooxygenase 2 (COX-2), tumour necrosis factor-alpha and the aggrecanases, a disintegrin and metalloprotease with thrombospondin motifs (ADAMTS)-4 and ADAMTS-5. A 90-day feeding period of n-3 LCPUFA increased serum phospholipid and synovial fluid lipid compositions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) compared to CONT horses. The reIL-1β injection caused an inflammatory response; however, there was no effect of dietary treatment on synovial fluid PGE2 content and MMP activity. Synovial tissue collected from N3FA horses exhibited lower expression of ADAMTS-4 compared to CONT horses. Despite the presence of EPA and DHA in the synovial fluid of N3FA horses, dietary n-3 LCPUFA supplementation did not modify synovial fluid biomarkers compared to CONT horses; however, the lower ADAMTS-4 mRNA expression in N3FA synovium warrants further

  10. Synthesis and evaluation of a tridentate Tc-99m labeled long chain fatty acid analog for myocardial imaging

    International Nuclear Information System (INIS)

    Long chain fatty acids serve as the main energy source for the myocardium. As an effort to develop Tc-99m labeled long chain fatty acid analogs due to ideal physical properties and ready availability of Tc-99m, we synthesized and evaluated a tridentate Tc-99m tricarbonyl-N2O-pentadecanoic acid ([Tc-99m]) as a novel radiotracer for myocardial imaging. The pyridinyl precursor of methyl pentadecanoate was prepared in high yield and reacted with [Tc-99m(CO)3(H2O)3]+ at 75 .deg. for 30 min, followed by hydrolysis in 0.4 N NaOH-MeOH. The resulting [Tc-99m] was purified by HPLC and redissolved in 5% ethanol-saline containing 5% bovine serum albumin. In vitro stability of [Tc-99m] was measured in human serum at 37 .deg. for 12 h using radio-TLC. Dynamic images were obtained in SD rats using a gamma camera. Re standard was synthesized as the synthesis of [Tc-99m] using [(NEt4)2[Re(CO)3CI3]. [Tc-99m] was synthesized in 70-78% radiochemical yield and with radiochemical purity higher than 98%. Re counterpart was used to identify the Tc-99m labeled fatty acid analog. [Tc-99m] was shown to be stable (>98%) over 12 h when incubated in human serum. Dynamic images showed rapid accumulation of the radioactivity in the liver, the heart. and the kidneys. ROIs were drawn in the liver and the heart, and their count/pixel ratios were obtained as 2.2:1, 7.5:1, and 16.5:1 at 1, 2 and 5 min postinjection, respectively. There was no significant uptake in the thyroid or salivary gland, indicating that Tc-99m pertechnetate was not regenerated during the time of the study. The results demonstrated that [Tc-99m] may be useful for myocardial imaging. Further studies are warranted to perform tissue distribution of [Tc-99m] in mice

  11. Very-long-chain polyunsaturated fatty acids in the retina: analysis and clinical relevance in physiological and pathological conditions

    Directory of Open Access Journals (Sweden)

    Berdeaux Olivier

    2011-09-01

    Full Text Available The retina is one of the vertebrate tissues with the highest content in polyunsaturated fatty acids (PUFA. A large proportion of retinal glycerophospholipids, especially those found in photoreceptor membranes, are dipolyunsaturated molecular species. Among them, dipolyunsaturated phosphatidylcholine (PC molecular species are known to contain very-long-chain polyunsaturated fatty acids (VLC-PUFA from the n-3 and n-6 series having 24-36 carbon atoms and four to six double bonds. Recent interest in the role played by VLC-PUFA arose from the findings that a protein called Elongation of very-long-chain fatty acids 4 (ELOVL4 is involved in their biosynthesis and that mutations in the ELOVL4 gene are associated with Stargardt-like macular dystrophy (STGD3, a dominantly inherited juvenile macular degeneration leading to vision loss. In this context, PC molecular species containing VLC-PUFA in retina must be precisely characterized to improve our understanding of the pathogenesis of STGD3. For 25 years, several current approaches using gas chromatography or gas chromatography-mass spectrometry have been used for the characterisation and quantification of VLC-PUFA. These methods allowed characterizing with precision the structures (carbon chain length and double bond positions of the different VLC-PUFA in bovine retina. Thus, retinal C28-C36 fatty acids are polyunsaturated and belong to the n-3 and n-6 families. The n-6 family of C28-C36 fatty acids has four or five double bonds, while the n-3 family of VLC-PUFA contains five or six double bonds. Moreover, some studies allowed determining the position of VLC-PUFA in the VLC-PC species. But most of these conventional approaches are timeconsuming, requiring successive extraction, chromatographic steps and often a derivatization step before. Recently, a normal LC-ESI-MS/MS method was proposed for the structural characterization and the quantification of VLC-PC species in retinas from bovines and human donors

  12. 40 CFR 721.9892 - Alkylated urea.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylated urea. 721.9892 Section 721... Alkylated urea. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an alkylated urea (PMN P-93-1649) is subject to reporting under...

  13. Study of surface tension and surface properties of binary systems of DMSO with long chain alcohols at various temperatures

    International Nuclear Information System (INIS)

    Highlights: • Surface tension of binary mixtures of alcohol/DMSO determined. • Surface mole fraction and surface thermodynamic parameters were calculated. • The surface tension data of binary mixtures were correlated with FLW, LWW and MS models. -- Abstract: Surface tensions of binary mixtures of DMSO (dimethyl sulphoxide) with a series of long chain aliphatic alcohols (1-propanol, 1-butanol, and 1-hexanol) were measured as a function of composition using the ring detachment method in the temperature range between (288.15 and 328.15) K. The surface tension results are used to describe quantitatively the nature, properties, and compositions of surface layers in binary liquid mixtures. The temperature influence on the behaviour of surface tensions and surface properties of binary mixtures has often been used to obtain information about solute structural effects on DMSO. The surface tension of the above mentioned binary systems were correlated with empirical and thermodynamic based models. The average relative error obtained from the comparison of experimental and calculated surface tension values for 15 binary systems with three models is less than 1%. In addition to finding more information about the surface structure of binary mixtures, surface mole fraction was calculated using an extended Langmuir model (EL). The temperature dependence of σ at fixed composition of solutions was used to estimate surface enthalpy, Hs, and surface entropy, Ss. The results provide information on the molecular interactions between the unlike molecules that exist at the surface and the bulk

  14. Assessment of crude glycerol for Enhanced Biological Phosphorus Removal: Stability and role of long chain fatty acids.

    Science.gov (United States)

    Tayà, Carlota; Guerrero, Javier; Suárez-Ojeda, María Eugenia; Guisasola, Albert; Baeza, Juan Antonio

    2015-12-01

    Enhanced Biological Phosphorus Removal (EBPR) of urban wastewaters is usually limited by the available carbon source required by Polyphosphate Accumulating Organisms (PAO). External carbon sources as volatile fatty acids (VFA) or other pure organic compounds have been tested at lab scale demonstrating its ability to enhance PAO activity, but the application of this strategy at full-scale WWTPs is not cost-effective. The utilization of industrial by-products with some of these organic compounds provides lower cost, but it has the possible drawback of having inhibitory or toxic compounds to PAO. This study is focused on the utilization of crude glycerol, the industrial by-product generated in the biodiesel production, as a possible carbon source to enhance EBPR in carbon-limited urban wastewaters. Crude glycerol has non-negligible content of other organic compounds as methanol, salts, VFA and long chain fatty acids (LCFA). VFA and methanol have been demonstrated to enhance PAO activity, but there is no previous study about the effect of LCFA on PAO. This work presents the operation of an EBPR SBR system using crude glycerol as sole carbon source, studying also its long-term stability. The effect of LCFA is evaluated at short and long-term operation, demonstrating for the first time EBPR activity with LCFA as sole carbon source and its long-term failure due to the increased hydrophobicity of the sludge. PMID:26092200

  15. Application of novel catalytic-ceramic-filler in a coupled system for long-chain dicarboxylic acids manufacturing wastewater treatment.

    Science.gov (United States)

    Wu, Suqing; Qi, Yuanfeng; Fan, Chunzhen; He, Shengbing; Dai, Bibo; Huang, Jungchen; Zhou, Weili; Gao, Lei

    2016-02-01

    To gain systematic technology for long-chain dicarboxylic acids (LDCA) manufacturing wastewater treatment, catalytic micro-electrolysis (CME) coupling with adsorption-biodegradation sludge (AB) process was studied. Firstly, novel catalytic-ceramic-filler was prepared from scrap iron, clay and copper sulfate solution and packed in the CME reactor. To remove residual n-alkane and LDCA, the CME reactor was utilized for LDCA wastewater pretreatment. The results revealed that about 94% of n-alkane, 98% of LDCA and 84% of chemical oxygen demand (COD) were removed by the aerated CME reactor at the optimum hydraulic retention time (HRT) of 3.0 h. In this process, catalysis from Cu and montmorillonites played an important role in improving the contaminants removal. Secondly, to remove residual COD in the wastewater, AB process was designed for the secondary biological treatment, about 90% of the influent COD could be removed by biosorption, bio-flocculation and biodegradation effects. Finally, the effluent COD (about 150 mg L(-1)) discharged from the coupled CME-AB system met the requirement of the national discharged standard (COD ≤ 300 mg L(-1)). All of these results suggest that the coupled CME-AB system is a promising technology due to its high-efficient performance, and has the potential to be applied for the real LDCA wastewater treatment. PMID:26619310

  16. Short-term long chain omega3 diet protects from neuroinflammatory processes and memory impairment in aged mice.

    Directory of Open Access Journals (Sweden)

    Virginie F Labrousse

    Full Text Available Regular consumption of food enriched in omega3 polyunsaturated fatty acids (ω3 PUFAs has been shown to reduce risk of cognitive decline in elderly, and possibly development of Alzheimer's disease. Docosahexaenoic acid (DHA and eicosapentaenoic acid (EPA are the most likely active components of ω3-rich PUFAs diets in the brain. We therefore hypothesized that exposing mice to a DHA and EPA enriched diet may reduce neuroinflammation and protect against memory impairment in aged mice. For this purpose, mice were exposed to a control diet throughout life and were further submitted to a diet enriched in EPA and DHA during 2 additional months. Cytokine expression together with a thorough analysis of astrocytes morphology assessed by a 3D reconstruction was measured in the hippocampus of young (3-month-old and aged (22-month-old mice. In addition, the effects of EPA and DHA on spatial memory and associated Fos activation in the hippocampus were assessed. We showed that a 2-month EPA/DHA treatment increased these long-chain ω3 PUFAs in the brain, prevented cytokines expression and astrocytes morphology changes in the hippocampus and restored spatial memory deficits and Fos-associated activation in the hippocampus of aged mice. Collectively, these data indicated that diet-induced accumulation of EPA and DHA in the brain protects against neuroinflammation and cognitive impairment linked to aging, further reinforcing the idea that increased EPA and DHA intake may provide protection to the brain of aged subjects.

  17. Impact of sustainable feeds on omega-3 long-chain fatty acid levels in farmed Atlantic salmon, 2006-2015.

    Science.gov (United States)

    Sprague, M; Dick, J R; Tocher, D R

    2016-01-01

    As the global population and its demand for seafood increases more of our fish will come from aquaculture. Farmed Atlantic salmon are a global commodity and, as an oily fish, contain a rich source of the health promoting long-chain omega-3 fatty acids, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Replacing the traditional finite marine ingredients, fishmeal and fish oil, in farmed salmon diets with sustainable alternatives of terrestrial origin, devoid of EPA and DHA, presents a significant challenge for the aquaculture industry. By comparing the fatty acid composition of over 3,000 Scottish Atlantic salmon farmed between 2006 and 2015, we find that terrestrial fatty acids have significantly increased alongside a decrease in EPA and DHA levels. Consequently, the nutritional value of the final product is compromised requiring double portion sizes, as compared to 2006, in order to satisfy recommended EPA + DHA intake levels endorsed by health advisory organisations. Nevertheless, farmed Scottish salmon still delivers more EPA + DHA than most other fish species and all terrestrial livestock. Our findings highlight the global shortfall of EPA and DHA and the implications this has for the human consumer and examines the potential of microalgae and genetically modified crops as future sources of these important fatty acids. PMID:26899924

  18. Shear-induced enhancements of crystallization kinetics and morphological transformation for long chain branched polylactides with different branching degrees

    Science.gov (United States)

    Wang, Junyang; Bai, Jing; Zhang, Yaqiong; Fang, Huagao; Wang, Zhigang

    2016-06-01

    The effects of long chain branching (LCB) degree on the shear-induced isothermal crystallization kinetics of a series of LCB polylactides (LCB PLAs) have been investigated by using rotational rheometer, polarized optical microscopy (POM) and scanning electron microscopy (SEM). Dynamic viscoelastic properties obtained by small-amplitude oscillatory shear (SAOS) tests indicate that LCB PLAs show more broadened relaxation time spectra with increasing LCB degree. Upon a pre-shear at the shear rate of 1 s‑1 LCB PLAs show much faster crystallization kinetics than linear PLA and the crystallization kinetics is enhanced with increasing LCB degree. By modeling the system as a suspension the quantitative evaluation of nucleation density can be derived from rheological experiments. The nucleation density is greatly enhanced with increasing LCB degree and a saturation in shear time is observed. Crystalline morphologies for LCB PLAs observed by POM and SEM demonstrate the enhancement of nucleation density with increasing LCB degree and a transformation from spherulitic to orientated crystalline morphologies. The observation can be ascribed to longer relaxation time of the longest macromolecular chains and broadened, complex relaxation behaviors due to the introduction of LCB into PLA, which is essential in stabilizing the orientated crystal nuclei after pre-shear.

  19. Heterotrophic Production of Omega-3 Long-Chain Polyunsaturated Fatty Acids by Trophically Converted Marine Diatom Phaeodactylum tricornutum

    Directory of Open Access Journals (Sweden)

    Mary L. Hamilton

    2016-03-01

    Full Text Available We have created via metabolic engineering a heterotrophic strain of Phaeodactylum tricornutum that accumulates enhanced levels of the high value omega-3 long chain polyunsaturated fatty acid (LC-PUFAs docosahexaenoic acid (DHA. This was achieved by generation of transgenic strains in which the Δ5-elongase from Ostreococcus tauri was co-expressed with a glucose transporter from the moss Physcomitrella patens. This double transformant has the capacity to grow in the dark in liquid medium supplemented with glucose and accumulate substantial levels of omega-3 LC-PUFAs. The effects of glucose concentrations on growth and LC-PUFA production of wild type and transformed strains cultivated in the light and dark were studied. The highest omega-3 LC-PUFAs accumulation was observed in cultures grown under mixotrophic conditions in the presence of 1% glucose (up to 32.2% of total fatty acids, TFA. Both DHA and EPA are detected at high levels in the neutral lipids of transgenic cells grown under phototrophic conditions, averaging 36.5% and 23.6% of TFA, respectively. This study demonstrates the potential for P. tricornutum to be developed as a viable commercial strain for both EPA and DHA production under mixo- and heterotrophic conditions.

  20. Tumor-suppressive functions of long-chain acyl-CoA synthetase 4 in gastric cancer.

    Science.gov (United States)

    Ye, Xiaojuan; Zhang, Yi; Wang, Xiao; Li, Yandong; Gao, Yong

    2016-04-01

    Long chain acyl CoA synthetase 4 (ACSL4) is a key enzyme in fatty acid metabolism with marked preference for arachidonic acid (AA). Recent reports have implicated its crucial roles in tumorigenesis. However in gastric cancer (GC), the expression and function of ACSL4 remain unclear. In the present study, we identified ACSL4 as a potential tumor suppressor in GC. The ACSL4 expression in GC samples was evaluated by real-time PCR and immunohistochemistry. The results indicated that the mRNA and protein levels of ACSL4 were frequently downregulated in cancer tissues compared with the adjacent non-cancerous mucosa control tissues. Cell-based functional assays exhibited that ectopic expression of ACSL4 inhibits cell growth, colony formation and cell migration, whereas ACSL4 knockdown enhanced these effects. In a nude mice model, ACSL4 knockdown also promoted subcutaneous xenografts' growth in vivo. Moreover, western blot analysis revealed that ACSL4 expression had a significant effect on FAK and P21 protein level. These findings suggest that ACSL4 plays a tumor-suppressive role and could be a potential therapeutic target in GC. PMID:26949059

  1. Heterotrophic Production of Omega-3 Long-Chain Polyunsaturated Fatty Acids by Trophically Converted Marine Diatom Phaeodactylum tricornutum.

    Science.gov (United States)

    Hamilton, Mary L; Powers, Stephen; Napier, Johnathan A; Sayanova, Olga

    2016-03-01

    We have created via metabolic engineering a heterotrophic strain of Phaeodactylum tricornutum that accumulates enhanced levels of the high value omega-3 long chain polyunsaturated fatty acid (LC-PUFAs) docosahexaenoic acid (DHA). This was achieved by generation of transgenic strains in which the Δ5-elongase from Ostreococcus tauri was co-expressed with a glucose transporter from the moss Physcomitrella patens. This double transformant has the capacity to grow in the dark in liquid medium supplemented with glucose and accumulate substantial levels of omega-3 LC-PUFAs. The effects of glucose concentrations on growth and LC-PUFA production of wild type and transformed strains cultivated in the light and dark were studied. The highest omega-3 LC-PUFAs accumulation was observed in cultures grown under mixotrophic conditions in the presence of 1% glucose (up to 32.2% of total fatty acids, TFA). Both DHA and EPA are detected at high levels in the neutral lipids of transgenic cells grown under phototrophic conditions, averaging 36.5% and 23.6% of TFA, respectively. This study demonstrates the potential for P. tricornutum to be developed as a viable commercial strain for both EPA and DHA production under mixo- and heterotrophic conditions. PMID:27005636

  2. Identification and quantification of triacylglycerols containing n-3 long-chain polyunsaturated fatty acids in bovine milk.

    Science.gov (United States)

    Liu, Zhiqian; Moate, Peter; Ezerniks, Vilnis; Cocks, Benjamin G; Rochfort, Simone

    2015-12-01

    The n-3 long-chain polyunsaturated fatty acids (LC-PUFA) are low-abundance components in milk fat, but have great potential in promoting human health. A comprehensive survey on triacylglycerol (TAG) molecular species in milk that contain at least one type of n-3 LC-PUFA, namely eicosapentaenoic acid, docosahexaenoic acid, and docosapentaenoic acid, was conducted in this work using HPLC-linear trap quadrupole-Orbitrap and HPLC-triple quadrupole mass spectrometry techniques. A total of 51 TAG species that contain n-3 LC-PUFA have been identified in bovine milk and their structures assigned. The TAG species containing docosahexaenoic acid were found in much smaller number and at much lower abundance compared with the other 2 types of TAG. An HPLC-triple quadrupole mass spectrometry-based method was developed, which provides relative quantification of all these TAG species in a run of 36 min. Application of this method to the quantification of n-3 LC-PUFA-incorporated TAG in 32 individual animal milk samples allowed us to determine variation between animals, identify strong metabolic relationships between TAG species, and reveal negative effect of a grape marc supplement on the accumulation of eicosapentaenoic acid in milk. PMID:26476942

  3. Coexpression of multiple genes reconstitutes two pathways of very long-chain polyunsaturated fatty acid biosynthesis in Pichia pastoris.

    Science.gov (United States)

    Kim, Sun Hee; Roh, Kyung Hee; Kim, Kwang-Soo; Kim, Hyun Uk; Lee, Kyeong-Ryeol; Kang, Han-Chul; Kim, Jong-Bum

    2014-09-01

    The introduction of novel traits to cells often requires the stable coexpression of multiple genes within the same cell. Herein, we report that C22 very long-chain polyunsaturated fatty acids (VLC-PUFAs) were synthesized from C18 precursors by reactions catalyzed by delta 6-desaturase, an ELOVL5 involved in VLC-PUFA elongation, and delta 5-desaturase. The coexpression of McD6DES, AsELOVL5, and PtD5DES encoding the corresponding enzymes, produced docosatetraenoic acid (C22:4 n-6) and docosapentaenoic acid (C22:5 n-3), as well as arachidonic acid (C20:4 n-6) and eicosapentaenoic acid (C20:5 n-3) in the methylotrophic yeast Pichia pastoris. The expression of each gene increased within 24 h, with high transcript levels after induction with 0.5 or 1 % methanol. High levels of the newly expressed VLC-PUFAs occurred after 144 h. This expression system exemplifies the recent progress and future possibilities of the metabolic engineering of VLC-PUFAs in oilseed crops. PMID:24863294

  4. Altered development and function of the placental regions in preeclampsia and its association with long-chain polyunsaturated fatty acids.

    Science.gov (United States)

    Rani, Alka; Wadhwani, Nisha; Chavan-Gautam, Preeti; Joshi, Sadhana

    2016-09-01

    The placenta is an essential organ formed during pregnancy that mainly transfers nutrients from the mother to the fetus. Nutrients taken up by the placenta are required for its own growth and development and to optimize fetal growth. Hence, placental function is an important determinant of pregnancy outcome. Among various nutrients, fatty acids, especially long-chain polyunsaturated fatty acids (LCPUFAs), including omega 3 and omega 6 fatty acids, are essential for placental development from the time of implantation. Studies have associated these LCPUFAs with placental development through their roles in regulating oxidative stress, angiogenesis, and inflammation, which may in turn influence their transfer to the fetus. The placenta has a heterogeneous morphology with variable regional vasculature, oxidative stress, and LCPUFA levels in healthy pregnancies depending upon the location within the placenta. However, these regional structural and functional parameters are found to be disturbed in pathological conditions, such as preeclampsia (PE), thereby affecting pregnancy outcome. Hence, the alterations in LCPUFA metabolism and transport in different regions of the PE placenta as compared with normal placenta could potentially be contributing to the pathological features of PE. The regional variations in development and function of the placenta and its possible association with placental LCPUFA metabolism and transport in normal and PE pregnancies are discussed in this review. WIREs Dev Biol 2016, 5:582-597. doi: 10.1002/wdev.238 For further resources related to this article, please visit the WIREs website. PMID:27239793

  5. Model-Based Reactor Design in Free-Radical Polymerization with Simultaneous Long-Chain Branching and Scission

    Directory of Open Access Journals (Sweden)

    Hidetaka Tobita

    2015-11-01

    Full Text Available Polymers are the products of processes and their microstructure can be changed significantly by the reactor systems employed, especially for nonlinear polymers. The Monte Carlo simulation technique, based on the random sampling technique, is used to explore the effect of reactor types on the branched polymer structure, formed through free-radical polymerization with simultaneous long-chain branching and scission, as in the case of low-density polyethylene synthesis. As a simplified model for a tower-type multi-zone reactor, a series of continuous stirred-tank reactors, consisting of one big tank and the same N-1 small tanks is considered theoretically. By simply changing the tank arrangement, various types of branched polymers, from star-like globular structure to a more randomly branched structure, can be obtained, while keeping the following properties of the final products, the monomer conversion to polymer, the average branching and scission densities, and the relationship between the mean-square radius of gyration and molecular weight.

  6. Characterization of coke deposited on nano-sized Pt-Pd/H-beta spent during long-chain paraffin hydroisomerization

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, F.; Einicke, W.D.; Ficht, K.; Glaeser, R. [Leipzig Univ. (Germany). Inst. of Chemical Technology; Bertmer, M. [Leipzig Univ. (Germany). Inst. of Experimental Physics II; Kuchling, T. [Technische Univ. Bergakademie Freiberg (Germany). Inst. of Energy Process Engineering and Chemical Engineering

    2013-11-01

    The hydroisomerization of long-chain n-paraffins were studied in the temperature range 205- 230 C at p{sub H2}=50 bar using a bench scale trickle-bed continuous-flow reactor. The bimetallic catalysts consisted of mixtures of platinum and palladium supported on commercially available nano-sized zeolites Beta (n{sub Si}/n{sub Al} = 12 and 25) extruded with a binder ({gamma}-alumina). For hexadecane conversion, high yields to isomers (25 and 45 wt.% of mono- and multibranched isomers, respectively) without extensive cracking (>10 wt.%) were obtained at a conversion of 80 %. Long-term tests with C{sub 16}H{sub 34} and blends of solid n-paraffins for 30-60 days on stream clearly indicate that a minor loss in catalyst activity can easily be compensated by increasing the reaction temperature from 230 C to 235 C. The zeolite sample with a 'mild acidity' revealed low hydrocracking at isomerization yield up to 70 wt.% and high stability. Carbonaceous deposits formed during n-paraffin hydroisomerization were investigated by temperature-programmed oxidation, elemental analysis, ATR-FTIR and {sup 13}C MAS NMR spectroscopy showing the formation of low-temperature, hydrogen-rich coke. (orig.)

  7. Structural advantage of sugar beet α-glucosidase to stabilize the Michaelis complex with long-chain substrate.

    Science.gov (United States)

    Tagami, Takayoshi; Yamashita, Keitaro; Okuyama, Masayuki; Mori, Haruhide; Yao, Min; Kimura, Atsuo

    2015-01-16

    The α-glucosidase from sugar beet (SBG) is an exo-type glycosidase. The enzyme has a pocket-shaped active site, but efficiently hydrolyzes longer maltooligosaccharides and soluble starch due to lower Km and higher kcat/Km for such substrates. To obtain structural insights into the mechanism governing its unique substrate specificity, a series of acarviosyl-maltooligosaccharides was employed for steady-state kinetic and structural analyses. The acarviosyl-maltooligosaccharides have a longer maltooligosaccharide moiety compared with the maltose moiety of acarbose, which is known to be the transition state analog of α-glycosidases. The clear correlation obtained between log Ki of the acarviosyl-maltooligosaccharides and log(Km/kcat) for hydrolysis of maltooligosaccharides suggests that the acarviosyl-maltooligosaccharides are transition state mimics. The crystal structure of the enzyme bound with acarviosyl-maltohexaose reveals that substrate binding at a distance from the active site is maintained largely by van der Waals interactions, with the four glucose residues at the reducing terminus of acarviosyl-maltohexaose retaining a left-handed single-helical conformation, as also observed in cycloamyloses and single helical V-amyloses. The kinetic behavior and structural features suggest that the subsite structure suitable for the stable conformation of amylose lowers the Km for long-chain substrates, which in turn is responsible for higher specificity of the longer substrates. PMID:25451917

  8. Brain white matter development is associated with a human-specific haplotype increasing the synthesis of long chain fatty acids.

    Science.gov (United States)

    Peters, Bart D; Voineskos, Aristotle N; Szeszko, Philip R; Lett, Tristram A; DeRosse, Pamela; Guha, Saurav; Karlsgodt, Katherine H; Ikuta, Toshikazu; Felsky, Daniel; John, Majnu; Rotenberg, David J; Kennedy, James L; Lencz, Todd; Malhotra, Anil K

    2014-04-30

    The genetic and molecular pathways driving human brain white matter (WM) development are only beginning to be discovered. Long chain polyunsaturated fatty acids (LC-PUFAs) have been implicated in myelination in animal models and humans. The biosynthesis of LC-PUFAs is regulated by the fatty acid desaturase (FADS) genes, of which a human-specific haplotype is strongly associated with ω-3 and ω-6 LC-PUFA concentrations in blood. To investigate the relationship between LC-PUFA synthesis and human brain WM development, we examined whether this FADS haplotype is associated with age-related WM differences across the life span in healthy individuals 9-86 years of age (n = 207). Diffusion tensor imaging was performed to measure fractional anisotropy (FA), a putative measure of myelination, of the cerebral WM tracts. FADS haplotype status was determined with a single nucleotide polymorphism (rs174583) that tags this haplotype. Overall, normal age-related WM differences were observed, including higher FA values in early adulthood compared with childhood, followed by lower FA values across older age ranges. However, individuals homozygous for the minor allele (associated with lower LC-PUFA concentrations) did not display these normal age-related WM differences (significant age × genotype interactions, p(corrected) < 0.05). These findings suggest that LC-PUFAs are involved in human brain WM development from childhood into adulthood. This haplotype and LC-PUFAs may play a role in myelin-related disorders of neurodevelopmental origin. PMID:24790207

  9. Structural basis for the discrepancy of spectral behavior in C-H stretching band between steroids and long chain hydrocarbon compounds

    Institute of Scientific and Technical Information of China (English)

    徐怡庄; 陶靖; 许振华; 翁诗甫; 徐建平; 吴瑾光; 徐端夫; 徐光宪

    1999-01-01

    The discrepancies of the spectral behavior for the C-H stretching band between some long chain hydrocarbon compounds and steroids were investigated. At low temperature, the C-H stretching bands exhibit complex fine structure in steroids but remain simple in long chain hydrocarbon compounds. MM3 molecular mechanics calculation indicates that, for long chain hydrocarbon compounds, the C-H groups vibrate with large scale coupling. There exist a few bands where the C-H groups vibrate in synchronous and inphase mode. Thus the variations of dipole moment for these bands are enhanced and the intensities are obviously stronger than others and cover other band in the spectra. This is just the reason why the C-H stretching bands are simple even at low temperature environment. Nevertheless, for the steroids, the C-H stretching bands vibrate with local coupling mode. The synchronous enhancement effect does not occur, the differences of intensities for various modes are not as large as those in long chain hydrocarbo

  10. Effect of a long-chained fructan Raftiline HP on blood lipids and spontaneous atherosclerosis in low density receptor knockout mice

    DEFF Research Database (Denmark)

    Mortensen, Alicja; Poulsen, Morten; Frandsen, Henrik Lauritz

    2002-01-01

    The effect of a long-chained fructan Raftiline HP on spontaneous hypercholesterolemia and atherosclerosis was studied in 40 LDLR-/- male mice receiving isocaloric, balanced in fat content, purified diets with 0 or 10% Raftiline HP, for 16 weeks. The feed intake was comparable (3.9 v. 3.8 g/day) but...

  11. Effect of a long-chained fructan Raftiline HP on blood lipids and spontaneous atherosclerosis in low density receptor knockout mice

    DEFF Research Database (Denmark)

    Mortensen, Alicja; Poulsen, Morten; Frandsen, Henrik Lauritz

    2002-01-01

    The effect of a long-chained fructan Raftiline HP on spontaneous hypercholesterolemia and atherosclerosis was studied in 40 LDLR-/- male mice receiving isocaloric, balanced in fat content, purified diets with 0 or 10% Raftiline HP, for 16 weeks. The feed intake was comparable (3.9 v. 3.8 g/day) b...

  12. Transient overshoot extensional rheology of long-chain branched polyethylenes: Experimental and numerical comparisons between filament stretching and cross-slot flow

    DEFF Research Database (Denmark)

    Hoyle, D.M.; Huang, Qian; Auhl, D.;

    2013-01-01

    This work analyses the high-strain extensional behavior of long-chain branched polyethylenes, employing two novel extensional rheometer devices, the filament stretching rheometer and the cross-slot extensional rheometer. The filament stretching rheometer uses an active feedback loop to control th...... confirming the agreement between the two experimental techniques. © 2013 The Society of Rheology....

  13. Development of low birthweight infants at 19 months of age correlates with early intake and status of long-chain polyunsaturated fatty acids

    NARCIS (Netherlands)

    Woltil, HA; van Beusekom, CM; Okken-Beukens, M; Schaafsma, A; Muskiet, FAJ; Okken, A

    1999-01-01

    We investigated the influence of early nutrition with and without long-chain polyunsaturated fatty acids (LCP) on later development of less than or equal to 2500 g newborns receiving preterm formula without LCP (n=75), preterm formula with 18:3 omega 6 and LCP omega 3 (at two doses; n=26) or their m

  14. Does supplementation of formula with evening primrose and fish oils augment long chain polyunsaturated fatty acid status of low birthweight infants to that of breast-fed counterparts?

    NARCIS (Netherlands)

    Woltil, HA; van Beusekom, CM; Schaafsma, A; Okken, A; Muskiet, FAJ

    1999-01-01

    We investigated whether formulae with evening primrose and fish oils raise long chain polyunsaturated fatty acids (LCPUFA) in plasma cholesterol esters (CE), erythrocytes (RSC) and platelets (PLT) to levels encountered in breast-fed infants. Low birthweight infants (less than or equal to 2500 g) rec

  15. The sphingolipid long-chain base-Pkh1/2-Ypk1/2 signaling pathway regulates eisosome assembly and turnover

    DEFF Research Database (Denmark)

    Luo, Guangzuo; Gruhler, Albrecht; Liu, Ying;

    2008-01-01

    Eisosomes are recently described fungal structures that play roles in the organization of the plasma membrane and endocytosis. Their major protein components are Pil1 and Lsp1, and previous studies showed that these proteins are phosphorylated by the sphingolipid long-chain base-activated Pkh1 an...

  16. Effect of three low-dose fish oil supplements, administered during pregnancy, on neonatal long-chain polyunsaturated fatty acid status at birth

    NARCIS (Netherlands)

    Velzing-Aarts, FV; van der Klis, FRM; van der Dijs, FPL; van Beusekom, CM; Landman, H; Capello, JJ; Muskiet, FAJ

    2001-01-01

    Adequate long-chain polyunsaturated fatty acid (LCP) status during pregnancy is important. We studied the effect of three low-dose fish oil supplements, administered during uncomplicated pregnancy, on neonatal LCP status at term delivery. Supplements were administered from the second trimester to de

  17. Identification of very-long-chain polyunsaturated fatty acids from Amphidinium carterae by atmospheric pressure chemical ionization liquid chromatography-mass spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Nedbalová, L.; Sigler, Karel

    2008-01-01

    Roč. 69, č. 12 (2008), s. 2391-2399. ISSN 0031-9422 Institutional research plan: CEZ:AV0Z50200510 Keywords : amphidinium carterae * very-long-chain polyunsaturated fatty acids * mass spectrometry Subject RIV: EE - Microbiology, Virology Impact factor: 2.946, year: 2008

  18. Long-chain polyunsaturated fatty acids in breast-milk and erythrocytes and neurodevelopmental outcomes in Danish late-preterm infants

    DEFF Research Database (Denmark)

    Andersen, Stine Brøndum; Hellgren, Lars I; Larsen, Mette Krogh; Verder, Henrik; Lauritzen, Lotte

    2015-01-01

    Background: The supply of long-chain polyunsaturated fatty acids (LC-PUFA) during pregnancy and early lactation has been shown to affect cognitive development in preterm infants, but the effect on early neurodevelopment of late-preterm infants has not yet been examined. Aim: To examine the fatty...

  19. Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans.

    Science.gov (United States)

    Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M A; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

    2015-03-01

    Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with α-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status. PMID:25573539

  20. Microchip Non-Aqueous Capillary Electrophoresis (MicronNACE) Method to Analyze Long-Chain Primary Amines

    Science.gov (United States)

    Willis, Peter A.; Mora, Maria; Cable, Morgan L.; Stockton, Amanda M.

    2012-01-01

    A protocol was developed as a first step in analyzing the complex organic aerosols present on Saturn's moon Titan, as well as the analogues of these aerosols (tholins) made on Earth. Labeling of primary amines using Pacific Blue succinimidyl ester is effected in ethanol with 25 mM triethylamine to maintain basic conditions. This reaction is allowed to equilibrate for at least one hour. Separation of the labeled primary amines is performed in ethanol with 1.05 M acetic acid, and 50 mM ammonium acetate in a commercial two-layer glass device with a standard crossmicrochannel measuring 50 microns wide by 20 microns deep. Injection potentials are optimized at 2 kV from the sample (negative) to the waste well (positive), with slight bias applied to the other two wells ( 0.4 and 0.8 V) to pinch the injection plug for the 30-s injection. Separation is performed at a potential of 5 kV along the channel, which has an effective separation distance of 7 cm. The use of ethanol in this method means that long-chain primary amines can be dissolved. Due to the low pH of the separation buffer, electro-osmotic flow (EOF) is minimized to allow for separation of both short-chain and longchain amines. As the freezing point of ethanol is much lower than water, this protocol can perform separations at temperatures lower than 0 C, which would not be possible in aqueous phase. This is of particular importance when considering in situ sampling of Titan aerosols, where unnecessary heating of the sample (even to room temperature) would lead to decomposition or unpredictable side reactions, which would make it difficult to characterize the sample appropriately.

  1. Concentrations and abundance ratios of long-chain alkenones and glycerol dialkyl glycerol tetraethers in sinking particles south of Java

    Science.gov (United States)

    Chen, Wenwen; Mohtadi, Mahyar; Schefuß, Enno; Mollenhauer, Gesine

    2016-06-01

    In this study, we obtained concentrations and abundance ratios of long-chain alkenones and glycerol dialkyl glycerol tetraethers (GDGTs) in a one-year time-series of sinking particles collected with a sediment trap moored from December 2001 to November 2002 at 2200 m water depth south of Java in the eastern Indian Ocean. We investigate the seasonality of alkenone and GDGT fluxes as well as the potential habitat depth of the Thaumarchaeota producing the GDGTs entrained in sinking particles. The alkenone flux shows a pronounced seasonality and ranges from 1 μg m-2 d-1 to 35 μg m-2 d-1. The highest alkenone flux is observed in late September during the Southeast monsoon, coincident with high total organic carbon fluxes as well as high net primary productivity. Flux-weighted mean temperature for the high flux period using the alkenone-based sea-surface temperature (SST) index U37K‧ is 26.7 °C, which is similar to satellite-derived Southeast (SE) monsoon SST (26.4 °C). The GDGT flux displays a weaker seasonality than that of the alkenones. It is elevated during the SE monsoon period compared to the Northwest (NW) monsoon and intermonsoon periods (approximately 2.5 times), which is probably related to seasonal variation of the abundance of Thaumarchaeota, or to enhanced export of GDGTs by aggregation with sinking phytoplankton detritus. Flux-weighted mean temperature inferred from the GDGT-based TEX86H index is 26.2 °C, which is 1.8 °C lower than mean annual (ma) SST but similar to SE monsoon SST. As the time series of TEX86H temperature estimates, however, does not record a strong seasonal amplitude, we infer that TEX86H reflects ma upper thermocline temperature at approximately 50 m water depth.

  2. Adult Medication-Free Schizophrenic Patients Exhibit Long-Chain Omega-3 Fatty Acid Deficiency: Implications for Cardiovascular Disease Risk

    Directory of Open Access Journals (Sweden)

    Robert K. McNamara

    2013-01-01

    Full Text Available Deficiency in long-chain omega-3 (LCn − 3 fatty acids, eicosapentaenoic acid (EPA, 20:5n − 3 and docosahexaenoic acid (DHA, 22:6n − 3, has been implicated in the pathoetiology of cardiovascular disease, a primary cause of excess premature mortality in patients with schizophrenia (SZ. In the present study, we determined erythrocyte EPA + DHA levels in adult medication-free patients SZ (n=20 and age-matched healthy controls (n=24. Erythrocyte EPA + DHA composition exhibited by SZ patients (3.5% was significantly lower than healthy controls (4.5%, −22%, P=0.007. The majority of SZ patients (72% exhibited EPA+DHA levels ≤4.0% compared with 37% of controls (Chi-square, P=0.001. In contrast, the omega-6 fatty acid arachidonic acid (AA, 20:4n−6 (+9%, P=0.02 and the AA:EPA + DHA ratio (+28%, P=0.0004 were significantly greater in SZ patients. Linoleic acid (18:2n−6 was significantly lower (−12%, P=0.009 and the erythrocyte 20:3/18:2 ratio (an index of delta6-desaturase activity was significantly elevated in SZ patients. Compared with same-gender controls, EPA + DHA composition was significantly lower in male (−19%, P=0.04 but not female (−13%, P=0.33 SZ patients, whereas the 20:3/18:2 ratio was significantly elevated in both male (+22%, P=0.008 and female (+22%, P=0.04 SZ patients. These results suggest that the majority of SZ patients exhibit low LCn − 3 fatty acid levels which may place them at increased risk for cardiovascular morbidity and mortality.

  3. Adult medication-free schizophrenic patients exhibit long-chain omega-3 Fatty Acid deficiency: implications for cardiovascular disease risk.

    Science.gov (United States)

    McNamara, Robert K; Jandacek, Ronald; Rider, Therese; Tso, Patrick; Dwivedi, Yogesh; Pandey, Ghanshyam N

    2013-01-01

    Deficiency in long-chain omega-3 (LCn - 3) fatty acids, eicosapentaenoic acid (EPA, 20:5n - 3) and docosahexaenoic acid (DHA, 22:6n - 3), has been implicated in the pathoetiology of cardiovascular disease, a primary cause of excess premature mortality in patients with schizophrenia (SZ). In the present study, we determined erythrocyte EPA + DHA levels in adult medication-free patients SZ (n = 20) and age-matched healthy controls (n = 24). Erythrocyte EPA + DHA composition exhibited by SZ patients (3.5%) was significantly lower than healthy controls (4.5%, -22%, P = 0.007). The majority of SZ patients (72%) exhibited EPA+DHA levels ≤4.0% compared with 37% of controls (Chi-square, P = 0.001). In contrast, the omega-6 fatty acid arachidonic acid (AA, 20:4n - 6) (+9%, P = 0.02) and the AA:EPA + DHA ratio (+28%, P = 0.0004) were significantly greater in SZ patients. Linoleic acid (18:2n - 6) was significantly lower (-12%, P = 0.009) and the erythrocyte 20:3/18:2 ratio (an index of delta6-desaturase activity) was significantly elevated in SZ patients. Compared with same-gender controls, EPA + DHA composition was significantly lower in male (-19%, P = 0.04) but not female (-13%, P = 0.33) SZ patients, whereas the 20:3/18:2 ratio was significantly elevated in both male (+22%, P = 0.008) and female (+22%, P = 0.04) SZ patients. These results suggest that the majority of SZ patients exhibit low LCn - 3 fatty acid levels which may place them at increased risk for cardiovascular morbidity and mortality. PMID:23533712

  4. Omega-3 long-chain fatty acids strongly induce angiopoietin-like 4 in humans12[S

    Science.gov (United States)

    Brands, Myrte; Sauerwein, Hans P.; Ackermans, Mariette T.; Kersten, Sander; Serlie, Mireille J.

    2013-01-01

    Angiopoietin-like 4 (ANGPTL4) is a regulator of LPL activity. In this study we examined whether different fatty acids have a differential effect on plasma ANGPTL4 levels during hyperinsulinemia in healthy lean males. In 10 healthy lean males, 3 hyperinsulinemic euglycemic clamps were performed during concomitant 6 h intravenous infusion of soybean oil (Intralipid® rich in PUFA), olive oil (Clinoleic® rich in MUFA) and control saline. In 10 other healthy lean males, 2 hyperinsulinemic clamps were performed during infusion of a mixed lipid emulsion containing a mixture of fish oil (FO), medium-chain triglycerides (MCTs), and long-chain triglycerides (LCTs) (FO/MCT/LCT; SMOFlipid®) or saline. FFA levels of approximately 0.5 mmol/l were reached during each lipid infusion. Plasma ANGPTL4 decreased during hyperinsulinemia by 32% (18–52%) from baseline. This insulin-mediated decrease in ANGPTL4 concentrations was partially reduced during concomitant infusion of olive oil and completely blunted during concomitant infusion of soybean oil and FO/MCT/LCT. The reduction in insulin sensitivity was similar between all lipid infusions. In accordance, incubation of rat hepatoma cells with the polyunsaturated fatty acid C22:6 increased ANGPTL4 expression by 70-fold, compared with 27-fold by the polyunsaturated fatty acid C18:2, and 15-fold by the monounsaturated fatty acid C18:1. These results suggest that ANGPTL4 is strongly regulated by fatty acids in humans, and is also dependent on the type of fatty acid. PMID:23319744

  5. Very-long-chain fatty acids restrict regeneration capacity by confining pericycle competence for callus formation in Arabidopsis.

    Science.gov (United States)

    Shang, Baoshuan; Xu, Chongyi; Zhang, Xixi; Cao, Huifen; Xin, Wei; Hu, Yuxin

    2016-05-01

    The already differentiated organs in plants have a remarkable capacity to regenerate new individuals under culture conditions. Plant in vitro regeneration practically starts with the induction of a pluripotent cell mass, the callus, from detached organs on auxin-rich callus-inducing medium (CIM), which is generally required for subsequent regeneration of new bodies. Recent studies show that CIM-induced callus formation occurs from the pericycle or pericycle-like cells through a root developmental pathway, whereas the signals involved in governing callus-forming capacity of pericycle cells remain unknown. Here we report that very-long-chain fatty acids (VLCFAs) play a critical role in confining the pericycle competence for callus formation and thus the regeneration capacity of Arabidopsis By genetic screening, we identified the callus formation-related 1 (cfr1) mutant, which bypasses the inhibition of callus-forming capacity in roots by solitary-root (slr/iaa14). We show that CFR1 encodes 3-ketoacyl-CoA synthase 1 (KCS1), which catalyzes a rate-limiting step of VLCFA biosynthesis. Our biochemical and genetic analyses demonstrate that VLCFAs restrict the pericycle competence for callus formation, at least in part, by regulating the transcription of Aberrant Lateral Root Formation 4 (ALF4). Moreover, we provide evidence that VLCFAs act as cell layer signals to mediate the pericycle competence for callus formation. Taken together, our results identify VLCFAs or their derivatives as the confining signals for mediating the pericycle competence for callus formation and thus the regeneration capacity of plant organs. PMID:27092001

  6. Involvement of atypical protein kinase C in the regulation of cardiac glucose and long-chain fatty acid uptake

    Directory of Open Access Journals (Sweden)

    JanGlatz

    2012-09-01

    Full Text Available Aim: The signaling pathways involved in the regulation of cardiac GLUT4 translocation/glucose uptake and CD36 translocation/ long-chain fatty acid uptake are not fully understood. We compared in heart/muscle-specific PKC-λ knockout mice the roles of atypical PKCs (PKC-ζ and PKC-λ in regulating cardiac glucose and fatty acid uptake. Results: Neither insulin-stimulated nor AMPK-mediated glucose and fatty acid uptake were inhibited upon genetic PKC-λ ablation in cardiomyocytes. In contrast, myristoylated PKC-ζ pseudosubstrate inhibited both insulin-stimulated and AMPK-mediated glucose and fatty acid uptake by >80% in both wild-type and PKC-λ-knockout cardiomyocytes. In PKC-λ knockout cardiomyocytes, PKC-ζ is the sole remaining atypical PKC isoform, and its expression level is not different from wild-type cardiomyocytes, in which it contributes to 29% and 17% of total atypical PKC expression and phosphorylation, respectively. Conclusion: Taken together, atypical PKCs are necessary for insulin-stimulated and AMPK-mediated glucose uptake into the heart, as well as for insulin-stimulated and AMPK-mediated fatty acid uptake. However, the residual PKC-ζ activity in PKC-λ-knockout cardiomyocytes is sufficient to allow optimal stimulation of glucose and fatty acid uptake, indicating that atypical PKCs are necessary but not rate-limiting in the regulation of cardiac substrate uptake and that PKC-λ and PKC-ζ have interchangeable functions in these processes.

  7. Long chain polyunsaturated fatty acids alter oxytocin signaling and receptor density in cultured pregnant human myometrial smooth muscle cells.

    Science.gov (United States)

    Kim, Paul Y; Zhong, Miao; Kim, Yoon-Sun; Sanborn, Barbara M; Allen, Kenneth G D

    2012-01-01

    Epidemiological studies and interventional clinical trials indicate that consumption of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) such as docosahexaenoic acid (DHA) lengthen gestational duration. Although the mechanisms are not well understood, prostaglandins (PG) of the 2-series are known to play a role in the initiation and progress of labor. In animal studies, modest DHA provision has been shown to reduce placental and uterine PGE(2) and PGF(2α), matrix metalloproteinase (MMP)-2 and MMP-9 expression, and placental collagenase activity. However, modulation of PG biosynthesis may not account for all the effects of LC n-3 PUFAs in labor. We investigated one potential PG-independent mechanism of LC PUFA action using cultured pregnant human myometrial smooth muscle cells. Our goal was to characterize the effect of LC PUFA treatment on oxytocin signaling, a potent uterotonic hormone involved in labor. The addition of 10 µM-100 µM DHA or arachidonic acid (AA) to the culture media for 48 h resulted in dose dependent enrichment of these fatty acids in membrane lipid. DHA and AA significantly inhibited phosphatidylinositol turnover and [Ca(2+)](i) mobilization with oxytocin stimulation compared to bovine serum albumin control and equimolar oleic acid. DHA and AA significantly reduced oxytocin receptor membrane concentration without altering binding affinity or rate of receptor internalization. These findings demonstrate a role for LC n-3 PUFAs in regulation of oxytocin signaling and provide new insight into additional mechanisms pertaining to reports of dietary fish and fish oil consumption prolonging gestation. PMID:22848573

  8. Methods of making alkyl esters

    Science.gov (United States)

    Elliott, Brian

    2010-08-03

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

  9. Ni-catalyzed alkylative dimerization of vinyl grignard reagents using alkyl fluorides.

    Science.gov (United States)

    Terao, Jun; Watabe, Hiroyasu; Kambe, Nobuaki

    2005-03-23

    Alkyl halides underwent unique cross-coupling reaction with vinylmagnesium chloride in the presence of Ni catalyst to give 2-alkyl-3-butenyl Grignard reagent (1) in high yields. This reaction proceeded efficiently at 25 degrees C in THF using primary and secondary alkyl fluorides. On the other hand, PhCH=CHMgBr gave double alkylative vinyl coupling product 4 in good yield as the sole coupling product. Alkyl fluorides react as the most suitable alkylating reagent in comparison to the corresponding chlorides, bromides, and iodides. PMID:15771474

  10. Towards the Industrial Production of Omega-3 Long Chain Polyunsaturated Fatty Acids from a Genetically Modified Diatom Phaeodactylum tricornutum.

    Directory of Open Access Journals (Sweden)

    Mary L Hamilton

    Full Text Available The marine diatom Phaeodactylum tricornutum can accumulate up to 30% of the omega-3 long chain polyunsaturated fatty acid (LC-PUFA eicosapentaenoic acid (EPA and, as such, is considered a good source for the industrial production of EPA. However, P. tricornutum does not naturally accumulate significant levels of the more valuable omega-3 LC-PUFA docosahexaenoic acid (DHA. Previously, we have engineered P. tricornutum to accumulate elevated levels of DHA and docosapentaenoic acid (DPA by overexpressing heterologous genes encoding enzyme activities of the LC-PUFA biosynthetic pathway. Here, the transgenic strain Pt_Elo5 has been investigated for the scalable production of EPA and DHA. Studies have been performed at the laboratory scale on the cultures growing in up to 1 L flasks a 3.5 L bubble column, a 550 L closed photobioreactor and a 1250 L raceway pond with artificial illumination. Detailed studies were carried out on the effect of different media, carbon sources and illumination on omega-3 LC-PUFAs production by transgenic strain Pt_Elo5 and wild type P. tricornutum grown in 3.5 L bubble columns. The highest content of DHA (7.5% of total fatty acids, TFA in transgenic strain was achieved in cultures grown in seawater salts, Instant Ocean (IO, supplemented with F/2 nutrients (F2N under continuous light. After identifying the optimal conditions for omega-3 LC-PUFA accumulation in the small-scale experiments we compared EPA and DHA levels of the transgenic strain grown in a larger fence-style tubular photobioreactor and a raceway pond. We observed a significant production of DHA over EPA, generating an EPA/DPA/DHA profile of 8.7%/4.5%/12.3% of TFA in cells grown in a photobioreactor, equivalent to 6.4 μg/mg dry weight DHA in a mid-exponentially growing algal culture. Omega-3 LC-PUFAs production in a raceway pond at ambient temperature but supplemented with artificial illumination (110 μmol photons m-2s-1 on a 16:8h light:dark cycle, in

  11. The impact of dietary long-chain polyunsaturated fatty acids on bone and cartilage in gilts and sows.

    Science.gov (United States)

    O'Connor-Robison, C I; Spencer, J D; Orth, M W

    2014-10-01

    Dietary long-chain PFO including arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are precursors for several inflammatory mediators. The objective of this study was to characterize the effects of dietary PFO supplementation on bone, cartilage, and synovial fluid in 2 ages of pigs. Sows and gilts were fed either control corn/soybean meal based diets or the control diet supplemented with PFO from Gromega (PFO; JBS United, Sheridan, IN). Sows were fed their diets for 24.5 mo and slaughtered at 43 mo while gilts were fed their diets from weaning until slaughter at 111 kg. Cartilage was harvested from both humeroulnar joints of 14 sows (7/treatment) and 16 gilts (8/treatment) within 30 h of slaughter for fatty acid analysis and explant cultures. Synovial fluid was collected from the carpal joints of each pig postmortem. The right fused radius/ulna was collected for computed tomography (CT) analysis. Cortical width and density were determined and trabecular density was measured at the distal radius. Cartilage explants were allocated to 24-well culture plates with 2 discs per well and cultured over 72 h at 37°C in serum-free Dulbecco's modified Eagle's medium: nutrient mixture F-12 (Ham) medium. Six wells/pig were treated with 10 ng/mL of recombinant porcine interleukin-1 (rpIL-1). At 24, 48, and 72 h of culture, media were removed and reserved for analysis of proteoglycans, nitric oxide (NO), and PGE2 concentrations. The CT scans of the radius/ulna from gilts revealed no differences for cortical width and bone density. Sows fed PFO had greater cortical width of the proximal ulna (P < 0.05) and decreased cortical width of the distal radius (P < 0.05). Sows fed PFO had increased DHA (P < 0.01) and a decrease in the omega-6 to omega-3 ratio (P < 0.05) in cartilage. Gilts fed PFO had increased DHA (P < 0.01), C22:1 (P < 0.01), and docosapentaenoic acid (P < 0.01) and a tendency for increased EPA (P = 0.093) concentrations in cartilage

  12. Dietary intervention increases n-3 long-chain polyunsaturated fatty acids in skeletal muscle membrane phospholipids of obese subjects. Implications for insulin sensitivity

    DEFF Research Database (Denmark)

    Haugaard, S.B.; Madsbad, S.; Høy, Carl-Erik;

    2006-01-01

    . Design Muscle membrane FA profiles were determined in muscle (vastus lateralis) biopsies from 21 obese subjects before and after 6 months of dietary restriction. Diet instructions emphasized low intake of FA of marine origin by recommending lean fish and prohibiting fatty fish and fish oil supplements......Objective Cross-sectional studies suggest that the fatty acid (FA) composition of phospholipids in skeletal muscle cell membrane may modulate insulin sensitivity in humans. We examined the impact of a hypocaloric low-fat dietary intervention on membrane FA composition and insulin sensitivity...... analysis that included changes in weight, fat mass, waist circumference, plasma lipids, PUFA, SFA and long-chain PUFAn-3 indicated that SFA and long-chain PUFAn-3 were independent predictors of HOMA-IR (R-2 = 0.33, P <0.01). Conclusions A hypocaloric low-fat dietary intervention programme increased...

  13. Dietary intervention increases n-3 long-chain polyunsaturated fatty acids in sceletal muscle membrane phospholipids of obese subjects. Inplications for insulin sensitivity

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Madsbad, Sten; Høy, C-E;

    2006-01-01

    . DESIGN Muscle membrane FA profiles were determined in muscle (vastus lateralis) biopsies from 21 obese subjects before and after 6 months of dietary restriction. Diet instructions emphasized low intake of FA of marine origin by recommending lean fish and prohibiting fatty fish and fish oil supplements......OBJECTIVE: Cross-sectional studies suggest that the fatty acid (FA) composition of phospholipids in skeletal muscle cell membrane may modulate insulin sensitivity in humans. We examined the impact of a hypocaloric low-fat dietary intervention on membrane FA composition and insulin sensitivity...... that included changes in weight, fat mass, waist circumference, plasma lipids, PUFA, SFA and long-chain PUFAn-3 indicated that SFA and long-chain PUFAn-3 were independent predictors of HOMA-IR (R(2)=0.33, P<0.01). CONCLUSIONS: A hypocaloric low-fat dietary intervention programme increased incorporation...

  14. Oxidative stability of fish and algae oils containing long-chain polyunsaturated fatty acids in bulk and in oil-in-water emulsions

    DEFF Research Database (Denmark)

    Frankel, E.N.; Satue-Gracia, T.; Meyer, Anne Boye Strunge; German, J.B.

    2002-01-01

    presence and activity of transition metals. Fish and algal oils were initially much more stable to oxidation in bulk systems than in the corresponding oil-in-water emulsions. The oxidative stability of emulsions cannot, therefore, be predicted on the basis of stability data obtained with bulk long......-chain PUFA-containing fish oils and DHA-containing algal oils. The relatively high oxidative stability of an algal oil containing 42% DHA was completely lost after chromatographic purification to remove tocopherols and other antioxidants. Therefore, this evidence does not support the claim that DHA-rich oils......The oxidative stability of long-chain polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA)-containing fish and algae oils varies widely according to their fatty acid composition, the physical and colloidal states of the lipids, the contents of tocopherols and other antioxidants, and the...

  15. Dietary intervention increases n-3 long-chain polyunsaturated fatty acids in skeletal muscle membrane phospholipids of obese subjects. Implications for insulin sensitivity

    DEFF Research Database (Denmark)

    Haugaard, S.B.; Madsbad, S.; Høy, Carl-Erik; Vaag, A.

    2006-01-01

    analysis that included changes in weight, fat mass, waist circumference, plasma lipids, PUFA, SFA and long-chain PUFAn-3 indicated that SFA and long-chain PUFAn-3 were independent predictors of HOMA-IR (R-2 = 0.33, P <0.01). Conclusions A hypocaloric low-fat dietary intervention programme increased......Objective Cross-sectional studies suggest that the fatty acid (FA) composition of phospholipids in skeletal muscle cell membrane may modulate insulin sensitivity in humans. We examined the impact of a hypocaloric low-fat dietary intervention on membrane FA composition and insulin sensitivity....... Design Muscle membrane FA profiles were determined in muscle (vastus lateralis) biopsies from 21 obese subjects before and after 6 months of dietary restriction. Diet instructions emphasized low intake of FA of marine origin by recommending lean fish and prohibiting fatty fish and fish oil supplements...

  16. Molecular sieve isolation technique for use in stable carbon isotope analysis of individual long-chain n-alkanes in crude oil

    International Nuclear Information System (INIS)

    An isolation procedure of microgram amounts of long-chain n-alkanes from crude oil using molecular sieve was examined for its applicability to stable carbon isotope analysis by gas chromatography/isotope ratio mass spectrometry (GC/IRMS). The procedure examined is as follows: molecular sieve (type 5A, 200 mg) in 1 ml of isooctane solvent are mixed with a saturated hydrocarbon fraction extracted from an appropriate amount (approx. 20 mg) of crude oil and stayed at room temperatures for more than 3 hours. Long-chain n-alkanes are isolated by extraction with n-hexane after dissolution of the resulting molecular sieve with 47% hydrofluoric acid solution. The recoveries were 90±6% for C15-C34 n-alkanes when their total amounts applied do not exceed 1.4 mg. No effect of the isolation procedure on carbon isotope ratios of n-alkanes was observed. (author)

  17. Enhanced production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in very long chain saturated fatty acid-accumulated macrophages

    OpenAIRE

    Kiyanagi Takashi; Sumiyoshi Katsuhiko; Kitamura Yohei; Kume Atsumi; Miyazaki Tetsuro; Shimada Kazunori; Yanagisawa Naotake; Iesaki Takafumi; Inoue Nao; Daida Hiroyuki

    2008-01-01

    Abstract Background Deterioration of peroxisomal β-oxidation activity causes an accumulation of very long chain saturated fatty acids (VLCSFA) in various organs. We have recently reported that the levels of VLCSFA in the plasma and/or membranes of blood cells were significantly higher in patients with metabolic syndrome and in patients with coronary artery disease than the controls. The aim of the present study is to investigate the effect of VLCSFA accumulation on inflammatory and oxidative ...

  18. Long-chain perfluoroalkyl carboxylic acids in Pacific cods from coastal areas in northern Japan: A major source of human dietary exposure

    International Nuclear Information System (INIS)

    This study investigates perfluoroalkyl carboxylic acids (PFCAs) contamination of edible fish muscle from Japanese coastal waters. The concentrations of PFCAs with 8–14 carbon atoms (C8–C14) in Pacific cods in Hokkaido, Japan were 51 (median: pg/g-wet weight) for C8, 93 for C9, 99 for C10, 746 for C11, 416 for C12, 404 for C13, and 93 for C14. The levels of C9–C14 PFCAs in fish were strongly correlated to each other, but not to C8 and the other chlorinated persistent organic pollutants, indicating that C9–C14 PFCAs have a different emission source and/or bioaccumulation mechanism. The relative ratios between estimated PFCAs intake through fish consumption and the reported total dietary exposure of PFCAs were less than 1 for C8 to C9, but were more than 1 for C10 to C14. This result strongly suggests that fish consumption is a significant source of human dietary exposure to C10–C14 PFCAs. - Highlights: • Perfluoroalkyl carboxylic acids were detected in edible cod fish from Japanese coastal waters. • The levels of long-chain PFCAs in fish were independent from those of C8 and other POPs. • Long chain PFCAs intake through fish and the reported total dietary exposure were comparable. • Sea fish such as Pacific cod may be a significant human dietary source of long-chain PFCAs. - Sea fish are a significant source of long-chain perfluoroalkyl carboxylic acids for the Japanese population

  19. Role of autophagy in the ω-3 long chain polyunsaturated fatty acid-induced death of lung cancer A549 cells

    OpenAIRE

    Yao, Qinghua; Fu, Ting; Wang, Lu; LAI, YUEBIAO; Wang, Yuqi; Xu, Chao; Huang, Lulu; Guo, Yong

    2015-01-01

    The present study identified that ω-3 long chain polyunsaturated fatty acids (ω-3 PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) demonstrate anti-proliferative effects in lung cancer A549 cells. MTS and cytotoxicity assays were conducted to confirm that ω-3 PUFAs induced cell death. Autophagy-associated gene and signaling pathways were also detected. Microtubule-associated protein light chain 3 (LC3) expression was found to be increased subsequent to treatment with DHA and...

  20. Low Blood Long Chain Omega-3 Fatty Acids in UK Children Are Associated with Poor Cognitive Performance and Behavior: A Cross-Sectional Analysis from the DOLAB Study

    OpenAIRE

    Montgomery, Paul; Burton, Jennifer R.; Sewell, Richard P.; Spreckelsen, Thees F; Richardson, Alexandra J.

    2013-01-01

    Background Omega-3 long-chain polyunsaturated fatty acids (LC-PUFA), especially DHA (docosahexaenonic acid) are essential for brain development and physical health. Low blood Omega-3 LC-PUFA have been reported in children with ADHD and related behavior/learning difficulties, as have benefits from dietary supplementation. Little is known, however, about blood fatty acid status in the general child population. We therefore investigated this in relation to age-standardized measures of behavior a...

  1. High Levels of Both n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids in Cord Serum Phospholipids Predict Allergy Development

    OpenAIRE

    Malin Barman; Sara Johansson; Bill Hesselmar; Wold, Agnes E.; Ann-Sofie Sandberg; Anna Sandin

    2013-01-01

    Background: Long-chain polyunsaturated fatty acids (LCPUFAs) reduce T-cell activation and dampen inflammation. They might thereby counteract the neonatal immune activation and hamper normal tolerance development to harmless environmental antigens. We investigated whether fatty acid composition of cord serum phospholipids affects allergy development up to age 13 years. Methods: From a population-based birth-cohort born in 1996/7 and followed until 13 years of age (n = 794), we selected cases w...

  2. DHA-Containing Oilseed: A Timely Solution for the Sustainability Issues Surrounding Fish Oil Sources of the Health-Benefitting Long-Chain Omega-3 Oils

    OpenAIRE

    Soressa M. Kitessa; Mahinda Abeywardena; Chakra Wijesundera; Nichols, Peter D.

    2014-01-01

    Benefits of long-chain (≥C20) omega-3 oils (LC omega-3 oils) for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega...

  3. Inhibition of serine palmitoyltransferase in vitro and long-chain base biosynthesis in intact Chinese hamster ovary cells by β-chloroalanine

    International Nuclear Information System (INIS)

    The effects of β-chloroalanine (β-Cl-alanine) on the serine palmitoyltransferase activity and the de novo biosynthesis of sphinganine and sphingenine were investigated in vitro with rat liver microsomes and in vivo with intact Chinese hamster ovary (CHO) cells. The inhibition in vitro was rapid, irreversible, and concentration and time dependent and apparently involved the active site because inactivation only occurred with β-Cl-L-alanine and was blocked by L-serine. These are characteristics of mechanism-based (suicide) inhibition. Serine palmitoyltransferase (SPT) was also inhibited when intact CHO cells were incubated with β-Cl-alanine and this treatment inhibited [14C]serine incorporation into long-chain bases by intact cells. The concentration dependence of the loss of SPT activity and of long-chain base synthesis was identical. The effects of β-Cl-alanine appeared to occur with little perturbation of other cell functions: the cells exhibited no loss in cell viability, [14C]serine uptake was not blocked, total lipid biosynthesis from [14C]acetic acid was not decreased (nor was the appearance of radiolabel in cholesterol and phosphatidylcholine), and [3H]thymidine incorporation into DNA was not affected. There appeared to be little effect on protein synthesis based on the incorporation of [3H]leucine, which was only decreased by 14%. Although β-Cl-L-alanine is known to inhibit other pyridoxal 5'-phosphate dependent enzymes, alanine and aspartate transaminases were not inhibited under these conditions. These results establish the close association between the activity of serine palmitoyltransferase and the cellular rate of long-chain base formation and indicate that β-Cl-alanine and other mechanism-based inhibitors might be useful to study alterations in cellular long-chain base synthesis

  4. Nutritional enrichment of vegetable oils with long-chain n-3 fatty acids through enzymatic interesterification with a new vegetable lipase

    OpenAIRE

    J.S. Sousa; Torres, A. G.; D.M.G. Freire

    2015-01-01

    The aim of the present work was to produce vegetable oils enriched with long-chain n-3 fatty acids of nutraceutical interest, through an enzyme-catalyzed interesterification with a new lipase, from physic nut (Jatropha curcas L.). The Vegetable Lipase Powder (biocatalyst) called VLP, which has never been applied in functional foods, was obtained from the physic nut seed, and efficiently hydrolyzed the 95% of waste fish oil in 24 h. Urea precipitation was used to concentrate polyunsaturated fa...

  5. Anaerobic biodegradation of long chain fatty acids : biomethanisation of biomass-associated LCFA as a challenge for the anaerobic treatment of effluents with high lipid/LCFA content

    OpenAIRE

    Pereira, M.A.

    2003-01-01

    Tese de doutoramento em Engenharia Biológica e Química. This work was focused on the anaerobic biodegradation of Long Chain Fatty Acids, especially those that are associated to anaerobic sludge by mechanisms of adsorption, precipitation or entrapment. When continuously fed with oleic acid (EGSB reactors, influent concentrations between 2 and 8 g COD/l and HRT=1 day), suspended and granular anaerobic sludge accumulated palmitic acid. This LCFA was efficiently biomethanised in batch assays, ...

  6. Diversity of Anaerobic Microorganisms Involved in Long-Chain Fatty Acid Degradation in Methanogenic Sludges as Revealed by RNA-Based Stable Isotope Probing▿

    OpenAIRE

    Hatamoto, Masashi; IMACHI, HIROYUKI; Yashiro, Yuto; Ohashi, Akiyoshi; Harada, Hideki

    2007-01-01

    Long-chain fatty acid (LCFA) degradation is a key step in methanogenic treatment of wastes/wastewaters containing high concentrations of lipids. However, despite the importance of LCFA-degrading bacteria, their natural diversity is little explored due to the limited availability of isolate information and the lack of appropriate molecular markers. We therefore investigated these microbes by using RNA-based stable isotope probing. We incubated four methanogenic sludges (mesophilic sludges MP a...

  7. Transport mechanisms and wetting dynamics in molecularly thin films of long-chain alkanes at solid/vapour interface : relation to the solid-liquid phase transition

    OpenAIRE

    Lazar, Paul

    2005-01-01

    Wetting and phase transitions play a very important role our daily life. Molecularly thin films of long-chain alkanes at solid/vapour interfaces (e.g. C30H62 on silicon wafers) are very good model systems for studying the relation between wetting behaviour and (bulk) phase transitions. Immediately above the bulk melting temperature the alkanes wet partially the surface (drops). In this temperature range the substrate surface is covered with a molecularly thin ordered, solid-like alkane film (...

  8. Inhibition of serine palmitoyltransferase in vitro and long-chain base biosynthesis in intact Chinese hamster ovary cells by. beta. -chloroalanine

    Energy Technology Data Exchange (ETDEWEB)

    Medlock, K.A.; Merrill, A.H. Jr.

    1988-09-06

    The effects of ..beta..-chloroalanine (..beta..-Cl-alanine) on the serine palmitoyltransferase activity and the de novo biosynthesis of sphinganine and sphingenine were investigated in vitro with rat liver microsomes and in vivo with intact Chinese hamster ovary (CHO) cells. The inhibition in vitro was rapid, irreversible, and concentration and time dependent and apparently involved the active site because inactivation only occurred with ..beta..-Cl-L-alanine and was blocked by L-serine. These are characteristics of mechanism-based (suicide) inhibition. Serine palmitoyltransferase (SPT) was also inhibited when intact CHO cells were incubated with ..beta..-Cl-alanine and this treatment inhibited (/sup 14/C)serine incorporation into long-chain bases by intact cells. The concentration dependence of the loss of SPT activity and of long-chain base synthesis was identical. The effects of ..beta..-Cl-alanine appeared to occur with little perturbation of other cell functions: the cells exhibited no loss in cell viability, (/sup 14/C)serine uptake was not blocked, total lipid biosynthesis from (/sup 14/C)acetic acid was not decreased (nor was the appearance of radiolabel in cholesterol and phosphatidylcholine), and (/sup 3/H)thymidine incorporation into DNA was not affected. There appeared to be little effect on protein synthesis based on the incorporation of (/sup 3/H)leucine, which was only decreased by 14%. Although ..beta..-Cl-L-alanine is known to inhibit other pyridoxal 5'-phosphate dependent enzymes, alanine and aspartate transaminases were not inhibited under these conditions. These results establish the close association between the activity of serine palmitoyltransferase and the cellular rate of long-chain base formation and indicate that ..beta..-Cl-alanine and other mechanism-based inhibitors might be useful to study alterations in cellular long-chain base synthesis.

  9. Long-chain SFA at the sn-1, 3 positions of TAG reduce body fat deposition in C57BL/6 mice.

    Science.gov (United States)

    Gouk, Shiou Wah; Cheng, Sit Foon; Mok, Josephine Shiueh Lian; Ong, Augustine Soon Hock; Chuah, Cheng Hock

    2013-12-14

    The present study aimed to determine the effect of positional distribution of long-chain SFA in TAG, especially at the sn-1, 3 positions, on fat deposition using the C57BL/6 mouse model. Throughout the 15 weeks of the study, mice were fed with diets fortified with palm olein (POo), chemically interesterified POo (IPOo) and soyabean oil (SOY). Mice receiving the SOY-enriched diet gained significantly higher amounts of subcutaneous fat (P= 0·011) and total fat (P= 0·013) compared with the POo group, despite similar body mass gain being recorded. During normalisation with food consumption to obtain the fat:feed ratio, mice fed with the POo-enriched diet exhibited significantly lower visceral (P= 0·044), subcutaneous (P= 0·006) and total (P= 0·003) fat:feed than those fed with the SOY-enriched diet. It is noteworthy that mice fed with the IPOo-enriched diet gained 14·3 % more fat per food consumed when compared with the POo group (P= 0·013), despite their identical total fatty acid compositions. This was mainly attributed to the higher content of long-chain SFA at the sn-1, 3 positions of TAG in POo, which results in delayed absorption after deacylation as evidenced by the higher amounts of long-chain SFA excreted in the faeces of mice fed with the POo-enriched diet. Negative correlations were found between the subcutaneous, visceral as well as total fat accretion per food consumption and the total SFA content at the sn-1, 3 positions, while no relationships were found for MUFA and PUFA. The present results show that the positional distribution of long-chain SFA exerts a more profound effect on body fat accretion than the total SFA content. PMID:23756564

  10. Fluorescent n-3 and n-6 Very Long Chain Polyunsaturated Fatty Acids: THREE-PHOTON IMAGING IN LIVING CELLS EXPRESSING LIVER FATTY ACID-BINDING PROTEIN*

    OpenAIRE

    McIntosh, Avery L.; Huang, Huan; Atshaves, Barbara P.; Wellberg, Elizabeth; Kuklev, Dmitry V.; Smith, William L.; Kier, Ann B.; Schroeder, Friedhelm

    2010-01-01

    Despite the considerable beneficial effects of n-3 and n-6 very long chain polyunsaturated fatty acids (VLC-PUFAs), very little is known about the factors that regulate their uptake and intracellular distribution in living cells. This issue was addressed in cells expressing liver-type fatty acid-binding protein (L-FABP) by real time multiphoton laser scanning microscopy of novel fluorescent VLC-PUFAs containing a conjugated tetraene fluorophore near the carboxyl group and natural methylene-in...

  11. Identification of an arylalkylamine N-acyltransferase from Drosophila melanogaster that catalyzes the formation of long-chain N-acylserotonins

    Science.gov (United States)

    Dempsey, Daniel R.; Jeffries, Kristen A.; Anderson, Ryan L.; Carpenter, Anne-Marie; Ospina, Santiago Rodriguez; Merkler, David J.

    2014-01-01

    Arylalkylamine N-acyltransferase-like 22 (AANATL2) from Drosophila melanogaster was expressed and shown to catalyze the formation of long-chain N-acylserotonins and N-acydopamines. Subsequent identification of endogenous amounts of N-acylserotonins and colocalization of these fatty acid amides and AANATL2 transcripts gives supporting evidence that AANATL2 has a role in the biosynthetic formation of these important cell signalling lipids. PMID:24444601

  12. Fatty acid profile and composition of milk protein fraction in dairy cows fed long-chain unsaturated fatty acids during the transition period

    Directory of Open Access Journals (Sweden)

    Francisco Palma Rennó

    2013-11-01

    Full Text Available The objective of this study was to evaluate the utilization of different sources of unsaturated long-chain fatty acids in diets for dairy cows during the transition period and early lactation on the milk fatty acid profile and composition of the protein fraction. Thirty-six Holstein cows were divided into three groups, fed the following diets: control (C; soybean oil (SO; and calcium salts of long-chain unsaturated fatty acids (CS. The milk samples utilized for analysis were obtained weekly from parturition to twelve weeks of lactation; each one of the samples originated from two daily milkings. Milk composition and total nitrogen, non-protein nitrogen and non-casein nitrogen levels were analyzed. The cows receiving the diet with calcium salts had lower concentrations of non-protein nitrogen (%CP in milk compared with the animals fed the diet with soybean oil. There was a decrease in concentration of medium-chain fatty acids C12-C16, and a concomitant increase in concentrations of long-chain fatty acids >C18 in milk fat for the animals fed the diets CS and SO when compared with diet C. Soybean oil and CS diets increased milk-fat concentrations of the acids C18: 1 trans-11, C18: 2 cis-9, trans-11 and C18: 2 trans-10 cis-12 in relation to diet C. The utilization of sources of long-chain fatty acids in the diet of dairy cows increases the biological value of milk in early lactation due to higher concentrations of specific fatty acids such as CLA C18: 2cis-9, trans-11.

  13. Field trial evaluation of the accumulation of omega-3 long chain polyunsaturated fatty acids in transgenic Camelina sativa: Making fish oil substitutes in plants

    OpenAIRE

    Sarah Usher; Haslam, Richard P.; Noemi Ruiz-Lopez; Olga Sayanova; Napier, Johnathan A.

    2015-01-01

    The global consumption of fish oils currently exceeds one million tonnes, with the natural de novo source of these important fatty acids forming the base of marine foodwebs. Here we describe the first field-based evaluation of a terrestrial source of these essential nutrients, synthesised in the seeds of transgenic Camelina sativa plants via the heterologous reconstitution of the omega-3 long chain polyunsaturated fatty acid biosynthetic pathway. Our data demonstrate the robust nature of this...

  14. Infants fed formula with added long chain polyunsaturated fatty acids have reduced incidence of respiratory illnesses and diarrhea during the first year of life

    OpenAIRE

    Lapillonne, Alexandre; Pastor, Nitida; Zhuang, Weihong; Scalabrin, Deolinda MF

    2014-01-01

    Background Long chain polyunsaturated fatty acids (LCPUFAs) may influence the immune system. Our objective was to compare the frequency of common illnesses in infants who received formula with or without added LCPUFAs. Methods In this observational, multi-center, prospective study, infants consumed formula with 17 mg DHA and 34 mg ARA/100 kcal (n = 233) or with no added DHA or ARA (n = 92). Pediatricians recorded respiratory illnesses, otitis media, eczema, and diarrhea through 1 year of age....

  15. The Scarlet Letter of Alkylation: A Mini Review of Selective Alkylating Agents

    OpenAIRE

    Oronsky, Bryan T.; Reid, Tony; Knox, Susan J.; Scicinski, Jan J.

    2012-01-01

    If there were a stigma scale for chemotherapy, alkylating agents would be ranked at the top of the list. The chemical term alkylation is associated with nonselective toxicity, an association that dates back to the use of nitrogen mustards during World War I as chemical warfare agents. That this stigma persists and extends to compounds that, through selectivity, attempt to “tame” the indiscriminate destructive potential of alkylation is the subject of this review. Selective alkylation, as it i...

  16. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells.

    Directory of Open Access Journals (Sweden)

    Kevin Kolahi

    Full Text Available While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5 and lipid metabolism (GPAT3, LPCAT3. We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism.

  17. Inhibition of the neutrophil oxidative burst by sphingoid long-chain bases: role of protein kinase C in the activation of the burst

    International Nuclear Information System (INIS)

    The neutrophil oxidative burst is triggered by a variety of both particulate (opsonized zymosan) and soluble agonists [formylmethionylleucylphenylalanine (FMLP), arachidonate, short-chained diacylglycerols (DAG) and phorbol myristate acetate (PMA)]. The authors show that the long-chain lipid bases sphinganine and sphingosine block activation of the burst in human neutrophils. Inhibition is reversible, does not alter cell viability, and does not affect phagocytosis. The inhibition affects the activation mechanism rather than the NADPH-oxidase enzyme. The structural requirements for inhibition include a hydrophobic carbon chain and an amino-containing headgroup, and the naturally occurring erythro sphinganine was more potent than the threo isomer. Activation of the oxidative burst by a variety of agonists was blocked by the same concentration of sphinganine indicating a common inhibited step. The authors suggest that the common step is protein kinase C, as evidenced by the following: 1) long-chain bases inhibit PKC in a micelle reconstituted system, 2) PMA-induced phophorylation is inhibited by sphinganine, and 3) sphinganine competes with (3H)-phorbol dibutyrate for its cytosolic receptor (i.e. protein kinase C). The authors suggest that sphingoid long-chain bases play a role in the cellular regulations

  18. Real-Time Tracking of BODIPY-C12 Long-Chain Fatty Acid in Human Term Placenta Reveals Unique Lipid Dynamics in Cytotrophoblast Cells

    Science.gov (United States)

    Louey, Samantha; Varlamov, Oleg; Thornburg, Kent

    2016-01-01

    While the human placenta must provide selected long-chain fatty acids to support the developing fetal brain, little is known about the mechanisms underlying the transport process. We tracked the movement of the fluorescently labeled long-chain fatty acid analogue, BODIPY-C12, across the cell layers of living explants of human term placenta. Although all layers took up the fatty acid, rapid esterification of long-chain fatty acids and incorporation into lipid droplets was exclusive to the inner layer cytotrophoblast cells rather than the expected outer syncytiotrophoblast layer. Cytotrophoblast is a progenitor cell layer previously relegated to a repair role. As isolated cytotrophoblasts differentiated into syncytialized cells in culture, they weakened their lipid processing capacity. Syncytializing cells suppress previously active genes that regulate fatty-acid uptake (SLC27A2/FATP2, FABP4, ACSL5) and lipid metabolism (GPAT3, LPCAT3). We speculate that cytotrophoblast performs a previously unrecognized role in regulating placental fatty acid uptake and metabolism. PMID:27124483

  19. Short communication: Influence of long-chain inulin and Lactobacillus paracasei subspecies paracasei on the sensory profile and acceptance of a traditional yogurt.

    Science.gov (United States)

    Pimentel, T C; Cruz, A G; Prudencio, S H

    2013-10-01

    The objectives of this study were to evaluate the influence of the addition of long-chain inulin as a fat replacer and prebiotic agent (20g/L) and (or) probiotic Lactobacillus paracasei ssp. paracasei on the sensory profile and acceptance of yogurts, and to assess the influence of descriptive attributes on the sensory acceptance of the products. The addition of inulin to low-fat yogurt improved its brightness and firmness, which was similar to the full-fat yogurt. However, the use of long-chain inulin increased the separation of serum and no influence on creaminess was observed. Regarding the product's acceptability, the low-fat yogurt with added inulin presented similar acceptance compared with the full-fat yogurt. The addition of Lb. paracasei ssp. paracasei did not affect the sensory profile and acceptance of the low-fat yogurt. Using external preference mapping, it was possible to verify that the sensory acceptance was driven positively by the sweetness and creaminess and negatively driven by firmness (appearance and texture) and homogeneity (appearance). It was possible to formulate low-fat yogurts with added probiotics that presented similar sensory characteristics to those of full-fat yogurts, and this was due to the addition of the long-chain inulin as a fat replacer. PMID:23932139

  20. Enzymes involved in the anaerobic oxidation of n-alkanes: from methane to long-chain paraffins

    Directory of Open Access Journals (Sweden)

    Amy V. Callaghan

    2013-05-01

    Full Text Available Anaerobic microorganisms play key roles in the biogeochemical cycling of methane and non-methane alkanes. To date, there appear to be at least three proposed mechanisms of anaerobic methane oxidation (AOM. The first pathway is mediated by consortia of archaeal anaerobic methane oxidizers and sulfate-reducing bacteria via ‘reverse methanogenesis’ and is catalyzed by a homologue of methyl-coenzyme M reductase. The second pathway is also mediated by anaerobic methane oxidizers and sulfate-reducing bacteria, wherein the archaeal members catalyze both methane oxidation and sulfate reduction and zero-valent sulfur is a key intermediate. The third AOM mechanism is a nitrite-dependent, intra-aerobic pathway described for the denitrifying bacterium, ‘Candidatus Methylomirabilis oxyfera.’ It is hypothesized that AOM proceeds via reduction of nitrite to nitric oxide, followed by the conversion of two nitric oxide molecules to dinitrogen and molecular oxygen. The latter can be used to functionalize the methane via a particulate methane monooxygenase. With respect to non-methane alkanes, there also appears to be novel mechanisms of activation. The most well-described pathway is the addition of non-methane alkanes across the double bond of fumarate to form alkyl-substituted succinates via the putative glycyl radical enzyme, alkylsuccinate synthase (also known as methylalkylsuccinate synthase. Other proposed mechanisms include anaerobic hydroxylation via ethylbenzene dehydrogenase-like enzymes and an ‘intra-aerobic’ denitrification pathway similar to that described for ‘M. oxyfera.’

  1. 40 CFR 721.8673 - [(Disubstituted phenyl)]azo dihydro hydroxy alkyl oxo alkyl-substituted-pyridines (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false azo dihydro hydroxy alkyl oxo alkyl... Significant New Uses for Specific Chemical Substances § 721.8673 azo dihydro hydroxy alkyl oxo alkyl...) The chemical substances identified generically as azo dihydro hydroxy alkyl oxo...

  2. Hydrodynamic bearings

    CERN Document Server

    Bonneau, Dominique; Souchet, Dominique

    2014-01-01

    This Series provides the necessary elements to the development and validation of numerical prediction models for hydrodynamic bearings. This book describes the rheological models and the equations of lubrication. It also presents the numerical approaches used to solve the above equations by finite differences, finite volumes and finite elements methods.

  3. Tripodal (N-alkylated) CMP(O) and malonamide ligands: synthesis, extraction of metal ions, and potentiometric studies

    NARCIS (Netherlands)

    Janczewski, Dominik; Reinhoudt, David N.; Verboom, Willem; Malinowska, Elzbieta; Pietrzak, Mariusz; Hill, Clement; Allignol, Cecile

    2007-01-01

    Tripodal ligands build on the C-pivot ( 9b–e, 13b–d, and 17a–d) and trialkylbenzene platforms ( 10a,b, 11, 12, 14a,b, and 18a,b) bearing (N-alkylated) carbamoylmethylphosphine oxide (CMPO), carbamoylmethylphosphonate (CMP), and malonamide moieties were synthesized. Extraction studies with Am3+ and E

  4. C-Alkylation by Hydrogen Autotransfer Reactions.

    Science.gov (United States)

    Obora, Yasushi

    2016-04-01

    The development of practical, efficient, and atom-economical methods for the formation of carbon-carbon bonds remains a topic of considerable interest in current synthetic organic chemistry. In this review, we have summarized selected topics from the recent literature with particular emphasis on C-alkylation processes involving hydrogen transfer using alcohols as alkylation reagents. This review includes selected highlights concerning recent progress towards the modification of catalytic systems for the α-alkylation of ketones, nitriles, and esters. Furthermore, we have devoted a significant portion of this review to the methylation of ketones, alcohols, and indoles using methanol. Lastly, we have also documented recent advances in β-alkylation methods involving the dimerization of alcohols (Guerbet reaction), as well as new developments in C-alkylation methods based on sp (3) C-H activation. PMID:27573136

  5. Bearing structures

    International Nuclear Information System (INIS)

    A hydrostatic bearing for the lower end of the vertical shaft of a sodium pump comprises a support shell encircling the shaft and a bush located between the shell and shaft. Liquid sodium is fed from the pump outlet to the bush/shaft and bush/shell interfaces to provide hydrostatic support. The bush outer surface and the shell inner surface are of complementary part-spherical shape and the bush floats relative to the shaft so that the bush can align itself with the shaft axis. Monitoring of the relative rotational speed of the bush with respect to the shaft (such rotation being induced by the viscous drag forces present) is also performed for the purposes of detecting abnormal operation of the bearing or partial seizure, at least one magnet is rotatable with the bush, and a magnetic sensor provides an output having a frequency related to the speed of the bush. (author)

  6. Tooling Converts Stock Bearings To Custom Bearings

    Science.gov (United States)

    Fleenor, E. N., Jr.

    1983-01-01

    Technique for reworking stock bearings saves time and produces helicopter-rotor bearings ground more precisely. Split tapered ring at one end of threaded bolt expands to hold inside of inner race bearing assembly; nut, at other end of bolt, adjusts amount of spring tension. Piece of hardware grasps bearing firmly without interfering with grinding operation. Operation produces bearing of higher quality than commercially available bearings.

  7. Increased long chain acyl-Coa synthetase activity and fatty acid import is linked to membrane synthesis for development of picornavirus replication organelles.

    Directory of Open Access Journals (Sweden)

    Jules A Nchoutmboube

    Full Text Available All positive strand (+RNA viruses of eukaryotes replicate their genomes in association with membranes. The mechanisms of membrane remodeling in infected cells represent attractive targets for designing future therapeutics, but our understanding of this process is very limited. Elements of autophagy and/or the secretory pathway were proposed to be hijacked for building of picornavirus replication organelles. However, even closely related viruses differ significantly in their requirements for components of these pathways. We demonstrate here that infection with diverse picornaviruses rapidly activates import of long chain fatty acids. While in non-infected cells the imported fatty acids are channeled to lipid droplets, in infected cells the synthesis of neutral lipids is shut down and the fatty acids are utilized in highly up-regulated phosphatidylcholine synthesis. Thus the replication organelles are likely built from de novo synthesized membrane material, rather than from the remodeled pre-existing membranes. We show that activation of fatty acid import is linked to the up-regulation of cellular long chain acyl-CoA synthetase activity and identify the long chain acyl-CoA syntheatse3 (Acsl3 as a novel host factor required for polio replication. Poliovirus protein 2A is required to trigger the activation of import of fatty acids independent of its protease activity. Shift in fatty acid import preferences by infected cells results in synthesis of phosphatidylcholines different from those in uninfected cells, arguing that the viral replication organelles possess unique properties compared to the pre-existing membranes. Our data show how poliovirus can change the overall cellular membrane homeostasis by targeting one critical process. They explain earlier observations of increased phospholipid synthesis in infected cells and suggest a simple model of the structural development of the membranous scaffold of replication complexes of picorna

  8. Depletion of ceramides with very long chain fatty acids causes defective skin permeability barrier function, and neonatal lethality in ELOVL4 deficient mice

    Directory of Open Access Journals (Sweden)

    Wenmei Li, Roger Sandhoff, Mari Kono, Patricia Zerfas, Vickie Hoffmann, Bryan Char-Hoa Ding, Richard L. Proia, Chu-Xia Deng

    2007-01-01

    Full Text Available Very long chain fatty acids (VLCFA, either free or as components of glycerolipids and sphingolipids, are present in many organs. Elongation of very long chain fatty acids-4 (ELOVL4 belongs to a family of 6 members of putative fatty acid elongases that are involved in the formation of VLCFA. Mutations in ELOVL4 were found to be responsible for an autosomal dominant form of Stargardt's-like macular dystrophy (STGD3 in human. We have previously disrupted the mouse Elovl4 gene, and found that Elovl4+/- mice were developmentally normal, suggesting that haploinsufficiency of ELOVL4 is not a cause for the juvenile retinal degeneration in STGD3 patients. However, Elovl4-/- mice died within several hours of birth for unknown reason(s. To study functions of ELOVL4 further, we have explored the causes for the postnatal lethality in Elovl4-/- mice. Our data indicated that the mutant mice exhibited reduced thickness of the dermis, delayed differentiation of keratinocytes, and abnormal structure of the stratum corneum. We showed that all Elovl4-/- mice exhibited defective skin water permeability barrier function, leading to the early postnatal death. We further showed that the absence of ELOVL4 results in depletion in the epidermis of ceramides with ω-hydroxy very long chain fatty acids (≥C28 and accumulation of ceramides with non ω-hydroxy fatty acids of C26, implicating C26 fatty acids as possible substrates of ELOVL4. These data demonstrate that ELOVL4 is required for VLCFA synthesis that is essential for water permeability barrier function of skin.

  9. Uptake of long chain fatty acids is regulated by dynamic interaction of FAT/CD36 with cholesterol/sphingolipid enriched microdomains (lipid rafts

    Directory of Open Access Journals (Sweden)

    Herrmann Thomas

    2008-08-01

    Full Text Available Abstract Background Mechanisms of long chain fatty acid uptake across the plasma membrane are important targets in treatment of many human diseases like obesity or hepatic steatosis. Long chain fatty acid translocation is achieved by a concert of co-existing mechanisms. These lipids can passively diffuse, but certain membrane proteins can also accelerate the transport. However, we now can provide further evidence that not only proteins but also lipid microdomains play an important part in the regulation of the facilitated uptake process. Methods Dynamic association of FAT/CD36 a candidate fatty acid transporter with lipid rafts was analysed by isolation of detergent resistant membranes (DRMs and by clustering of lipid rafts with antibodies on living cells. Lipid raft integrity was modulated by cholesterol depletion using methyl-β-cyclodextrin and sphingolipid depletion using myriocin and sphingomyelinase. Functional analyses were performed using an [3H]-oleate uptake assay. Results Overexpression of FAT/CD36 and FATP4 increased long chain fatty acid uptake. The uptake of long chain fatty acids was cholesterol and sphingolipid dependent. Floating experiments showed that there are two pools of FAT/CD36, one found in DRMs and another outside of these domains. FAT/CD36 co-localized with the lipid raft marker PLAP in antibody-clustered domains at the plasma membrane and segregated away from the non-raft marker GFP-TMD. Antibody cross-linking increased DRM association of FAT/CD36 and accelerated the overall fatty acid uptake in a cholesterol dependent manner. Another candidate transporter, FATP4, was neither present in DRMs nor co-localized with FAT/CD36 at the plasma membrane. Conclusion Our observations suggest the existence of two pools of FAT/CD36 within cellular membranes. As increased raft association of FAT/CD36 leads to an increased fatty acid uptake, dynamic association of FAT/CD36 with lipid rafts might regulate the process. There is no

  10. Isolation of cytotoxic glucoerebrosides and long-chain bases from sea cucumber Cucumaria frondosa using high speed counter-current chromatography.

    Science.gov (United States)

    Xu, Jie; Guo, Shuang; Du, Lei; Wang, Yu-Ming; Sugawara, Tatsuya; Hirata, Takashi; Xue, Chang-Hu

    2013-01-01

    Total glucocerebrosides of the sea cucumber Cucumaria frondosa (CFC) have been isolated from the less polar lipid fraction of the chloroform-methanol extract using high speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of petroleum ether-methanol-water (5:4:1, v/v). Three glucocerebroside molecular species (CFC-1, CFC-2 and CFC-3) were isolated from crude total cerebrosides with repeated column chromatography. The structures of these three glucocerebroside molecular species were determined on the basis of chemical and spectroscopic evidence: fatty acids were mainly saturated (C22:0 and C18:0), monounsaturated (C24:1 and C20:1) and α-hydroxyl fatty acids (C24:1h, C23:0h, C23:1h and C22:0h), the structures of long-chain bases were dihydroxy (d17:1, d18:2 and d18:1) and trihydroxy (t17:0 and t16:0), and the glycosylation was glucose. High purity long-chain bases of sea cucumber Cucumaria frondosa (CF-LCB) were prepared from total lipids by HSCCC with a two-phase solvent system composed of n-hexane-methyl tert butyl ether-methanol-water (1:1:2:1, v/v). Compare with traditional preparative methods, the method of HSCCC is short cycle, high yield and less solvent consumption. The composition analysis of CF-LCB showed that the ratio of d18:2 and d17:1 was approximately 2:1. The four glucocerebrosides and long-chain bases from sea cucumber Cucumaria frondosa were evaluated for activity in vitro assays for the cytotoxic activities against Caco-2 colon cancer cells. The results indicated that both glucocerebrosides and long-chain bases exhibited an inhibitory effect on cell proliferation. Moreover, CFC-3 was most effective in four glucocerebrosides to Caco-2 cell viability. The inhibition effect of CF-LCB was much stronger than glucocerebrosides. PMID:23470440

  11. Effects of supplemental long-chain omega-3 fatty acids and erythrocyte membrane fatty acid content on circulating inflammatory markers in a randomized controlled trial of healthy adults

    OpenAIRE

    Flock, Michael R.; Skulas-Ray, Ann C.; William S. Harris; Gaugler, Trent L.; Fleming, Jennifer A.; Kris-Etherton, Penny M

    2014-01-01

    The long-chain omega-3 polyunsaturated (n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), may have anti-inflammatory effects. We evaluated the dose-response effect of EPA+DHA supplementation on circulating TNF-α, IL-6, and CRP and explored associations between red blood cell (RBC) membrane PUFA content and TNF-α, IL-6, and CRP. Young adults with low fish intake (n = 116) received one of five doses (0, 300, 600, 900, or 1,800 mg/d EPA+DHA) for 5 months. There were no significan...

  12. Readily Available Sources of Long-Chain Omega-3 Oils: Is Farmed Australian Seafood a Better Source of the Good Oil than Wild-Caught Seafood?

    OpenAIRE

    Nichols, Peter D.; Brett Glencross; Petrie, James R.; Singh, Surinder P.

    2014-01-01

    Seafood consumption enhances intake of omega-3 long-chain (≥C20) polyunsaturated fatty acids (termed LC omega-3 oils). Humans biosynthesize only small amounts of LC-omega-3, so they are considered semi-essential nutrients in our diet. Concern has been raised that farmed fish now contain lower LC omega-3 content than wild-harvested seafood due to the use of oil blending in diets fed to farmed fish. However, we observed that two major Australian farmed finfish species, Atlantic salmon (Salmo ...

  13. Characterization of the Medium- and Long-Chain n-Alkanes Degrading Pseudomonas aeruginosa Strain SJTD-1 and Its Alkane Hydroxylase Genes

    OpenAIRE

    Liu, Huan; Xu, Jing; Liang, Rubing; Liu, Jianhua

    2014-01-01

    A gram-negative aliphatic hydrocarbon-degrading bacterium SJTD-1 isolated from oil-contaminated soil was identified as Pseudomonas aeruginosa by comparative analyses of the 16S rRNA sequence, phenotype, and physiological features. SJTD-1 could efficiently mineralize medium- and long-chain n-alkanes (C12-C30) as its sole carbon source within seven days, showing the most optimal growth on n-hexadecane, followed by n-octadecane, and n-eicosane. In 36 h, 500 mg/L of tetradecane, hexadecane, and o...

  14. Long-Chain Acetylenic Ketones from the Micronesian Sponge Haliclona sp. Importance of the 1-yn-3-ol Group for Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Guang-Xiong Zhou

    2003-11-01

    Full Text Available Abstract: Two new long-chain C33 polyacetylenic compounds, halicynones A and B were isolated from the marine sponge Haliclona sp. along with known analogs. The known compound pellynol A possessing a 1-yn-3-ol terminus, exhibited strong antitumor activity against the human colon tumor cell line HCT-116 (IC50 0.026 μg/mL, however, the corresponding 1-yn-3-one, halicynone A, was inactive, which suggests an important role for the terminal 1-yn-3-ol functional group in mediating cytotoxic activity.

  15. THE EFFECT OF SULPHURIC ACID CONCENTRATION ON SOLVENT EXTRACTION OF ReO4 - BY THE LONG-CHAIN ALIPHATIC TERTIARY AMINES AND ALCOHOLS

    Directory of Open Access Journals (Sweden)

    Aleksander G. Kasikov

    2010-06-01

    Full Text Available The effect of sulphuric acid concentration on solvent extraction of ReO4- by the long-chain aliphatic tertiary amines and alcohols in a wide range of H2SO4 concentrations in initial solutions is discussed. It has been established that the influence of the sulphuric acid concentration on rhenium solvent extraction is largely due to the extraction process mechanism. In the case of the anion-exchange mechanism, ReO4- is best extracted from weakly acidic solutions, whereas when the hydrate-solvate mechanism takes place – from solutions containing 4-7 mole/l H2SO4.

  16. Bioavailability of seocalcitol I: Relating solubility in biorelevant media with oral bioavailability in rats--effect of medium and long chain triglycerides

    DEFF Research Database (Denmark)

    Grove, Mette; Pedersen, Gitte P; Nielsen, Jeanet L; Müllertz, Anette

    2005-01-01

    influence of fatty acid chain length on the in vitro solubility of seocalcitol. The same solubility of seocalcitol was found in media containing either MC-LP or LC-LP. The bioavailability after oral administration of seocalcitol dissolved in medium chain triglyceride (MCT), long chain triglyceride (LCT...... intestine and protection against precipitation of seocalcitol in the gastro intestinal tract. There was no difference in the in vivo bioavailability of seocalcitol between the MCT and the LCT solutions, which correlates with the identical in vitro solubility of seocalcitol in SIM containing MC-LP or LC-LP....

  17. The effect of sulphuric acid concentration on solvent extraction of ReO4 - by the long-chain aliphatic tertiary amines and alcohols

    International Nuclear Information System (INIS)

    The effect of sulphuric acid concentration on solvent extraction of ReO4 - by the long-chain aliphatic tertiary amines and alcohols in a wide range of H2SO4 concentrations in initial solutions is discussed. It has been established that the influence of the sulphuric acid concentration on rhenium solvent extraction is largely due to the extraction process mechanism. In the case of the anion-exchange mechanism, ReO4 - is best extracted from weakly acidic solutions, whereas when the hydrate-solvate mechanism takes place - from solutions containing 4-7 mole/l H2SO4. (authors)

  18. The effect of fatty acid positioning in dietary triacylglycerols and intake of long-chain n-3 polyunsaturated fatty acids on bone mineral accretion in growing piglets

    DEFF Research Database (Denmark)

    Andersen, Anders Daniel; Ludvig, Stine E; Damsgaard, Camilla Trab;

    2013-01-01

    Long-chain n-3 PUFA (LCPUFA) and palmitate (16:0) positioning in the triacylglycerol (TAG) of infant formula may affect calcium-uptake which could affect bone health. We investigated if a human milk fat substitute (HMFS) with a modified TAG structure holding 16:0 predominantly in the sn-2-position...... computed tomography and mechanical strength. Bone mineral content (BMC) was higher in the FO compared to the SO-group (p=0.03). Despite similar weight gain in HMFS- and CONT-groups, body fat accumulation was higher with HMFS (p...

  19. Extra virgin olive oil reduces liver oxidative stress and tissue depletion of long-chain polyunsaturated fatty acids produced by a high saturated fat diet in mice

    OpenAIRE

    Valenzuela, R.; Hernandez-Rodas, M. C.; Espinosa, A.; Rincón, M. A.; Romero, N; Barrera, C. (Carlos); Marambio, M.; Vivero, J.; Valenzuela, A.

    2016-01-01

    Long-chain polyunsaturated fatty acids (LCPUFA) which are synthesized mainly in the liver have relevant functions in the organism. A diet high in fat (HFD) generates an increase in the levels of fat and induces oxidative stress (lipo-peroxidation) in the liver, along with a reduction in tissue n-3 and n-6 LCPUFA. Extra virgin olive oil (EVOO) is rich in anti-oxidants (polyphenols and tocopherols) which help to prevent the development of oxidative stress. This study evaluated the role of EVOO ...

  20. Different effects of short- and long-chained fructans on large intestinal physiology and carcinogen-induced aberrant crypt foci in rats

    DEFF Research Database (Denmark)

    Poulsen, Morten; Molck, Anne-Marie; Jacobsen, Bodil Lund

    2002-01-01

    the development of ACF: microflora, short-chain fatty acids, pH, and cell proliferation. A 3-wk pretreatment period with both fructans was included. Feeding the long-chained fructan (5% or 15%) significantly inhibited the numbers of small and total ACF after 5 and 10 wk. The short-chained fructan (15......-type fructan on 1,2-dimethylhydrazine dihydrochloride-induced aberrant crypt foci (ACF) in the rat colon. In addition, the present study investigated the influence of chain length, dietary level (5% or 15%), and duration of feeding (5 or 10 wk) on the following intestinal parameters supposed to be involved in...

  1. Modulation of voltage-dependent Ca channel current by arachidonic acid and other long-chain fatty acids in rabbit intestinal smooth muscle

    OpenAIRE

    1992-01-01

    The effects of arachidonic acid (AA) and other long-chain fatty acids on voltage-dependent Ca channel current (ICa) were investigated, with the whole cell patch clamp method, in longitudinal smooth muscle cells of rabbit ileum. 10-30 microM AA caused a gradual depression of ICa. The inhibitory effect of AA was not prevented by indomethacin (10 microM) (an inhibitor of cyclooxygenase) or nordihydroguaiaretic acid (10 microM) (an inhibitor of lipoxygenase). 1-(5-Isoquinolinesulfonyl)- 2-methylp...

  2. Spectrophotometric characteristics of 4-(2-pyridylazo)-resorcinol and its complex with cadmium in the presence of long-chain surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Tananajko, M.M.; Vysotskaya, T.I. (Kievskij Gosudarstvennyj Univ. (Ukrainian SSR))

    1982-06-01

    Spectrophotometric characteristics of 4-(2-pyridylazo)-resorcinol (PAR) are studied in a wide pH range depending on the concentration of long-chain surfactants: cetylpyridinium chloride (a cationic surfactant) and OP-10 (a nonionic surfactant). The bathochromic shift of reagent absorption bands is shown. Absorption spectra of the reagent and PAR chelate with cadmium are compared. It is shown that introduction of surfactants studied increases the sensibility of reactions for cadmium. The effect is clearly manifested with introduction of cetyl pyridinium chloride.

  3. What Is the Most Effective Way of Increasing the Bioavailability of Dietary Long Chain Omega-3 Fatty Acids—Daily vs. Weekly Administration of Fish Oil?

    OpenAIRE

    Samaneh Ghasemifard; Sinclair, Andrew J.; Gunveen Kaur; Paul Lewandowski; Turchini, Giovanni M.

    2015-01-01

    The recommendations on the intake of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) vary from eating oily fish (“once to twice per week”) to consuming specified daily amounts of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (“250–500 mg per day”). It is not known if there is a difference in the uptake/bioavailability between regular daily consumption of supplementsvs. consuming fish once or twice per week. In this study, the bioavailability of a daily dose of n-3 LC...

  4. The roles of long-chain polyunsaturated fatty acids in pregnancy, lactation and infancy: review of current knowledge and consensus recommendations

    OpenAIRE

    Koletzko, Berthold; Lien, Eric; Agostoni, Carlo; Böhles, Hansjosef; Campoy, Cristina; Cetin, Irene; Decsi, Tamas; Dudenhausen, Joachim W.; Dupont, Cristophe; Forsyth, Stewart; Hoesli, Irene; Holzgreve, Wolfgang; Lapillonne, Alexandre; Putet, Guy; Secher, Niels J.

    2008-01-01

    This paper reviews current knowledge on the role of the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (AA, 20:4n-6), in maternal and term infant nutrition as well as infant development. Consensus recommendations and practice guidelines for health-care providers supported by the World Association of Perinatal Medicine, the Early Nutrition Academy, and the Child Health Foundation are provided. The fetus and neonate should receive LC-...

  5. A novel long-chain acyl-derivative of epigallocatechin-3-O-gallate prepared and purified from green tea polyphenols

    Institute of Scientific and Technical Information of China (English)

    陈平; 谭曜; 孙东; 郑小明

    2003-01-01

    Lipophilic tea polyphenols (LTP) were prepared by catalytic esterifieation of green tea polyphenols (GRIP) with hexadeeanoyl chloride. A novel long-chain aeyl-derivative of epigalloeateehin-3-o-gallate(EGCG) was first isolated from purification of LTP by high-speed eountereurrent ehromatography (HSCCC)using a solvent system composed of n-hexane-ethyl acetate-methanol-water ( 1 : 1 : 1 : 1, v/v) . The moleeularstructure of the acyl-derivative, Epigallocatechin-3-O-gallate-4'-O-hexadeeanate , was elucidated by meansof elemental analysis, IR, 1H-NMR and MS spectra.

  6. Characterization of Oilseed Lipids from “DHA-Producing Camelina sativa”: A New Transformed Land Plant Containing Long-Chain Omega-3 Oils

    OpenAIRE

    Mansour, Maged P; Pushkar Shrestha; Srinivas Belide; Petrie, James R.; Nichols, Peter D.; Singh, Surinder P.

    2014-01-01

    New and sustainable sources of long-chain (LC, ≥C20) omega-3 oils containing DHA (docosahexaenoic acid, 22:6ω3) are required to meet increasing demands. The lipid content of the oilseed of a novel transgenic, DHA-producing land plant, Camelina sativa, containing microalgal genes able to produce LC omega-3 oils, contained 36% lipid by weight with triacylglycerols (TAG) as the major lipid class in hexane extracts (96% of total lipid). Subsequent chloroform-methanol (CM) extraction recovered fur...

  7. An alternate pathway to long-chain polyunsaturates: the FADS2 gene product Δ8-desaturates 20:2n-6 and 20:3n-3

    OpenAIRE

    Park, Woo Jung; Kothapalli, Kumar S. D.; Lawrence, Peter; Tyburczy, Cynthia; Brenna, J. Thomas

    2009-01-01

    The mammalian Δ6-desaturase coded by fatty acid desaturase 2 (FADS2; HSA11q12-q13.1) catalyzes the first and rate-limiting step for the biosynthesis of long-chain polyunsaturated fatty acids. FADS2 is known to act on at least five substrates, and we hypothesized that the FADS2 gene product would have Δ8-desaturase activity. Saccharomyces cerevisiae transformed with a FADS2 construct from baboon neonate liver cDNA gained the function to desaturate 11,14-eicosadienoic acid (20:2n-6) and 11,14,1...

  8. Reaction of Lithium Diethylamide with an Alkyl Bromide and Alkyl Benzenesulfonate: Origins of Alkylation, Elimination, and Sulfonation

    OpenAIRE

    Gupta, Lekha; Ramírez, Antonio; Collum, David B.

    2010-01-01

    A combination of NMR, kinetic, and computational methods are used to examine reactions of lithium diethylamide in tetrahydrofuran (THF) with n-dodecyl bromide and n-octyl benzenesulfonate. The alkyl bromide undergoes competitive SN2 substitution and E2 elimination in proportions independent of all concentrations except for a minor medium effect. Rate studies show that both reactions occur via trisolvated-monomer-based transition structures. The alkyl benzenesulfonate undergoes competitive SN2...

  9. A Literature Survey to Identify Potentially Volatile Iodine-Bearing Species Present in Off-Gas Streams

    Energy Technology Data Exchange (ETDEWEB)

    Bruffey, S. H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Spencer, B. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Strachan, D. M. [Strata-G, Knoxville, TN (United States); Jubin, R. T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Soelberg, N. R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Riley, B. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-06-30

    Four radionuclides have been identified as being sufficiently volatile in the reprocessing of nuclear fuel that their gaseous release needs to be controlled to meet regulatory requirements (Jubin et al. 2011, 2012). These radionuclides are 3H, 14C, 85Kr, and 129I. Of these, 129I has the longest half-life and potentially high biological impact. Accordingly, control of the release of 129I is most critical with respect to the regulations for the release of radioactive material in stack emissions. It is estimated that current EPA regulations (EPA 2010) would require any reprocessing plant in the United States to limit 129I release to less than 0.05 Ci/MTIHM for a typical fuel burnup of 55 gigawatt days per metric tonne (GWd/t) (Jubin 2011). The study of inorganic iodide in off-gas systems has been almost exclusively limited to I2 and the focus of organic iodide studies has been CH3I. In this document, we provide the results of an examination of publically available literature that is relevant to the presence and sources of both inorganic and organic iodine-bearing species in reprocessing plants. We especially focus on those that have the potential to be poorly sequestered with traditional capture methodologies. Based on the results of the literature survey and some limited thermodynamic modeling, the inorganic iodine species hypoiodous acid (HOI) and iodine monochloride (ICl) were identified as potentially low-sorbing iodine species that could present in off-gas systems. Organic species of interest included both short chain alkyl iodides such as methyl iodide (CH3I) and longer alkyl iodides up to iodododecane (C10H21I). It was found that fuel dissolution may provide conditions conducive to HOI formation and has been shown to result in volatile long-chain alkyl iodides, though these may not volatilize until later in the reprocessing sequence. Solvent extraction processes were found to be significant sources of various organic iodine-bearing species; formation of these

  10. Fluorinated alkyl substances and technical mixtures used in food paper-packaging exhibit endocrine-related activity in vitro

    DEFF Research Database (Denmark)

    Rosenmai, Anna Kjerstine; Taxvig, Camilla; Svingen, Terje;

    2016-01-01

    Migration of chemicals from packaging materials to foods may lead to human exposure. Polyfluoroalkyl substances (PFAS) can be used in technical mixtures (TMs) for use in food packaging of paper and board, and PFAS have been detected in human serum and umbilical cord blood. The specific structures...... of the PFAS in TMs are often unknown, but polyfluorinated alkyl phosphate esters (PAPs) have been characterized in TMs, food packaging, and in food. PAPs can be metabolized into fluorotelomer alcohols (FTOHs) and perfluoroalkyl carboxylic acids (PFCAs). Some PFAS have endocrine activities, highlighting...... the need to investigate these effects. Herein, we studied the endocrine activity of less characterized PFAS, including short-chain PFCAs and FTOHs, PAPs, and TMs of unknown chemical composition. Long-chain PFCAs were also included. We applied seven assays covering effects on estrogen, glucocorticoid...

  11. Fluorinated alkyl substances and technical mixtures used in food paper-packaging exhibit endocrine-related activity in vitro.

    Science.gov (United States)

    Rosenmai, A K; Taxvig, C; Svingen, T; Trier, X; van Vugt-Lussenburg, B M A; Pedersen, M; Lesné, L; Jégou, B; Vinggaard, A M

    2016-07-01

    Migration of chemicals from packaging materials to foods may lead to human exposure. Polyfluoroalkyl substances (PFAS) can be used in technical mixtures (TMs) for use in food packaging of paper and board, and PFAS have been detected in human serum and umbilical cord blood. The specific structures of the PFAS in TMs are often unknown, but polyfluorinated alkyl phosphate esters (PAPs) have been characterized in TMs, food packaging, and in food. PAPs can be metabolized into fluorotelomer alcohols (FTOHs) and perfluoroalkyl carboxylic acids (PFCAs). Some PFAS have endocrine activities, highlighting the need to investigate these effects. Herein, we studied the endocrine activity of less characterized PFAS, including short-chain PFCAs and FTOHs, PAPs, and TMs of unknown chemical composition. Long-chain PFCAs were also included. We applied seven assays covering effects on estrogen, glucocorticoid, androgen, and peroxisome proliferator-activated receptor (PPAR) activity, as well as steroidogenesis in vitro and ex vivo. In general, PAPs, FTOHs, TMs, and long-chain PFCAs showed estrogenic activity through receptor activation and/or increasing 17β-estradiol levels. Furthermore, short- and long-chain PFCAs activated PPARα and PPARγ. Collectively, this means that (i) PAPs, FTOHs, and PFCAs exhibit endocrine activity through distinct and sometimes different mechanisms, (ii) two out of three tested TMs exhibited estrogenic activity, and (iii) short-chain FTOHs showed estrogenic activity and short-chain PFCAs generally activate both PPARα and PPARγ with similar potency and efficacy as long-chain PFCAs. In conclusion, several new and divergent toxicological targets were identified for different groups of PFAS. PMID:27152447

  12. Novel long-chain anteiso-alkanes and anteiso-alkanoic acids in Antarctic rocks colonized by living and fossil cryptoendolithic microorganisms

    Science.gov (United States)

    Matsumoto, G. I.; Friedmann, E. I.; Watanuki, K.; Ocampo-Friedmann, R.

    1992-01-01

    Saponified extracts of rock samples colonized by cryptoendolithic microbial communities from the McMurdo Dry Valleys of Southern Victoria Land, Antarctica, were separated into hydrocarbon and fatty acid fractions by silica gel column chromatography. Hydrocarbons and methyl esters of fatty acids were analyzed by capillary gas chromatography-mass spectrometry. Unusually, a suite of long-chain anteiso-alkanes (a-C20 to a-C30) and anteiso-alkanoic acids (a-C20 to a-C30) were detected in many samples, together with straight-chain, branched and/or cyclic and acyclic isoprenoid compounds. These novel compounds are probably derived from unidentified heterotrophic bacteria or symbiotic processes in a unique microbial community in the Antarctic cold desert and suggest the occurrence of a special biosynthetic pathway. Long-chain anteiso-alkanes are probably formed through microbial decarboxylation of corresponding anteiso-alkanoic acids. They may serve as new biomarkers in environmental and geochemical studies.

  13. Microemulsions containing long-chain oil ethyl oleate improve the oral bioavailability of piroxicam by increasing drug solubility and lymphatic transportation simultaneously.

    Science.gov (United States)

    Xing, Qiao; Song, Jia; You, Xiuhua; Xu, Dongling; Wang, Kexin; Song, Jiaqi; Guo, Qin; Li, Pengyu; Wu, Chuanbin; Hu, Haiyan

    2016-09-25

    Drug solubility and lymphatic transport enhancements are two main pathways to improve drug oral bioavailability for microemulsions. However, it is not easy to have both achieved simultaneously because excipients used for improving lymphatic transport were usually insufficient in forming microemulsions and solubilizing drugs. Our research is to explore whether ethyl oleate, an oil effective in developing microemulsions with desired solubilizing capability, could increase bioavailability to a higher extent by enhancing lymphatic transport. As a long-chain oil, ethyl oleate won larger microemulsion area than short-chain tributyrin and medium-chain GTCC. In contrast, long-chain soybean oil failed to prepare microemulsions. The solubility of piroxicam in ethyl oleate microemulsions (ME-C) increased by about 30 times than in water. ME-C also won significantly higher AUC0-t compared with tributyrin microemulsions (ME-A) and GTCC microemulsions (ME-B). Oral bioavailability in ME-C decreased by 38% after lymphatic transport was blocked by cycloheximide, severer than those in ME-A and ME-B (8% and 34%). These results suggest that improving lymphatic transport and solubility simultaneously might be a novel strategy to increase drug oral bioavailability to a higher extent than increasing solubility only. Ethyl oleate is a preferred oil candidate due to its integrated advantages of high solubilizing capability, large microemulsion area and effective lymphatic transport. PMID:27473280

  14. Different effects of short- and long-chained fructans on large intestinal physiology and carcinogen-induced aberrant crypt foci in rats.

    Science.gov (United States)

    Poulsen, Morten; Mølck, Anne-Marie; Jacobsen, Bodil Lund

    2002-01-01

    Inulin-type fructans, which are nondigestible carbohydrates, have been shown to modulate the number of induced preneoplastic lesions in the colon as well as the colonic microflora in laboratory animals. The present study was designed to investigate the effect of a short- and long-chained inulin-type fructan on 1,2-dimethylhydrazine dihydrochloride-induced aberrant crypt foci (ACF) in the rat colon. In addition, the present study investigated the influence of chain length, dietary level (5% or 15%), and duration of feeding (5 or 10 wk) on the following intestinal parameters supposed to be involved in the development of ACF: microflora, short-chain fatty acids, pH, and cell proliferation. A 3-wk pretreatment period with both fructans was included. Feeding the long-chained fructan (5% or 15%) significantly inhibited the numbers of small and total ACF after 5 and 10 wk. The short-chained fructan (15%) inhibited the number of small and total ACF after 5 and 10 wk but significantly increased the numbers of medium and large ACF after 10 wk. In conclusion, the effect on ACF outcome was influenced by the chain length of the fructans. PMID:12416260

  15. Short term effects of dietary medium-chain fatty acids and n-3 long-chain polyunsaturated fatty acids on the fat metabolism of healthy volunteers

    Directory of Open Access Journals (Sweden)

    Hauenschild A

    2003-11-01

    Full Text Available Abstract Background The amount and quality of dietary fatty acids can modulate the fat metabolism. Objective This dietary intervention is based on the different metabolic pathways of long-chain saturated fatty acids (LCFA, which are mostly stored in adipocytic triacylglycerols, medium-chain fatty acids (MCFA which are preferentially available for hepatic mitochondrial β-oxidation and n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA suggested to modulate fat oxidation and storage by stimulating the peroxisomal β-oxidation. Combined dietary MCFA and n-3 LCPUFA without LCFA may synergistically stimulate fatty acid oxidation resulting in blood lipid clearance and LCFA release from adipocytes. Design In a short term, parallel, randomized, double-blind trial effects on the fatty acid metabolism of 10 healthy volunteers (Body Mass Index 25–30 of a formula containing 72% MCFA and 22% n-3 LCPUFA without LCFA (intake: 1.500 kcal/day; fat: 55.5% of energy were measured in comparison to an isoenergetic formula with equal fat amount and LCFA dominated lipid profile. Results The plasma triacylglycerol (p Conclusion Combined dietary 72% MCFA and 22% n-3 LCPUFA without LCFA stimulate the fatty acid oxidation and release from adipocytes without affecting any safety parameters measured.

  16. Medium-chain versus long-chain triacylglycerol emulsion hydrolysis by lipoprotein lipase and hepatic lipase: Implications for the mechanisms of lipase action

    Energy Technology Data Exchange (ETDEWEB)

    Deckelbaum, R.J. (Columbia Univ., New York, NY (USA)); Hamilton, J.A.; Butbul, E.; Gutman, A. (Boston Univ. Medical Center, MA (USA)); Moser, A. (Hadassah Univ. Hospital, Jerusalem (Israel)); Bengtsson-Olivecrona, G.; Olivecrona, T. (Univ. of Umea (Sweden)); Carpentier, Y.A. (St. Pierre Univ. Hospital, Brussels (Belgium))

    1990-02-06

    To explore how enzyme affinities and enzyme activities regulate hydrolysis of water-insoluble substrates, the authors compared hydrolysis of phospholipid-stabilized emulsions of medium-chain (MCT) versus long-chain triacylglycerols (LCT). Because substrate solubility at the emulsion surface might modulate rates of hydrolysis, the ability of egg yolk phosphatidylcholine to solubilize MCT was examined by NMR spectroscopy. Chemical shift measurements showed that 11 mol % of ({sup 13}C)carbonyl enriched trioctanoin was incorporated into phospholipid vesicles as a surface component. Line widths of trioctanoin surface peaks were half that of LCT, and relaxation times, T{sub 1}, were also shorter for trioctanoin, showing greater mobility for MCT in phospholipid. In assessing the effects of these differences in solubility on lipolysis, they found that both purified bovine milk lipoprotein lipase and human hepatic lipase hydrolyzed MCT at rates at least 2-fold higher than for LCT. Differences in affinity were also demonstrated in mixed incubations where increasing amounts of LCT emulsion resulted in decreased hydrolysis of MCT emulsions. These results suggest that despite lower enzyme affinity for MCT emulsions, shorter chain triacylglycerols are more readily hydrolyzed by lipoprotein and hepatic lipases than long-chain triacylglycerols because of greater MCT solubility and mobility at the emulsion-water interface.

  17. The long chain of the n-hexane fraction of water hyacinth (eichhornia crassipes): extrction, estimation, GC-MS analysis and antimicrobial activity

    International Nuclear Information System (INIS)

    Oily fraction was extracted from the water hyacinth (Eichhornia crassipes) using n-hexane by both cold and hot extraction in 5.5 ± 0.05% and 9.30 ± 0.05%, respectively, however, no difference was found in the nature of the compounds extracted by the two processes. The analysis of this oil was carried out using GC-FID and GC-MS in separate experiments and the nature of the compounds was investigated by library matching of the spectra obtained through GC-MS. This extract was found to contain 33.267% of the nonadecan-4-ol and 20.51% of a long chain ketone in addition to various quantities of the long chain nitrogenous compounds. The antibacterial activity of the extract was investigated against eight pathogenic bacteria and fungus Candida albican using disc diffusion method. The extract was found to be highly active against all tested bacterial strains except S. typhi. For most of the strains the activity of the extract was near the reference. Ciprofloxacin, clotrimazole and erythromycin were used as reference antibiotics. (author)

  18. Development of bioreporter assays for the detection of bioavailability of long-chain alkanes based on the marine bacterium Alcanivorax borkumensis strain SK2.

    Science.gov (United States)

    Kumari, Rekha; Tecon, Robin; Beggah, Siham; Rutler, Rebecca; Arey, J Samuel; van der Meer, Jan Roelof

    2011-10-01

    Long-chain alkanes are a major component of crude oil and therefore potentially good indicators of hydrocarbon spills. Here we present a set of new bacterial bioreporters and assays that allow to detect long-chain alkanes. These reporters are based on the regulatory protein AlkS and the alkB1 promoter from Alcanivorax borkumensis SK2, a widespread alkane degrader in marine habitats. Escherichia coli cells with the reporter construct reacted strongly to octane in short-term (6 h) aqueous suspension assays but very slightly only to tetradecane, in line with what is expected from its low water solubility. In contrast, long-term assays (up to 5 days) with A. borkumensis bioreporters showed strong induction with tetradecane and crude oil. Gel-immobilized A. borkumensis reporter cells were used to demonstrate tetradecane and crude oil bioavailability at a distance from a source. Alcanivorax borkumensis bioreporters induced fivefold more rapid and more strongly when allowed physical contact with the oil phase in standing flask assays, suggesting a major contribution of adhered cells to the overall reporter signal. Using the flask assays we further demonstrated the effect of oleophilic nutrients and biosurfactants on oil availability and degradation by A. borkumensis. The fluorescence signal from flask assays could easily be captured with a normal digital camera, making such tests feasible to be carried out on, e.g. marine oil responder vessels in case of oil accidents. PMID:21895911

  19. Rapid identification of long-chain polyunsaturated fatty acids in a marine extract by HPLC-MS using data-dependent acquisition.

    Science.gov (United States)

    Thomas, Michael C; Dunn, Simon R; Altvater, Jens; Dove, Sophie G; Nette, Geoffrey W

    2012-07-17

    The collision-induced dissociation (CID) of a range of deprotonated fatty acid standards was studied using linear ion trap mass spectrometry. Neutral losses of 78, 98, and 136 Da were consistently observed for fatty acids with five or more double bonds. Comparison of the MS/MS spectra of docosahexaenoic acid (DHA) and universally (13)C-labeled DHA allowed the molecular formulas for these neutral losses to be determined as C(6)H(6), C(5)H(6)O(2), and C(8)H(8)O(2). Knowledge of fatty acid fragmentation processes was then applied to identify fatty acids from a sea anemone, Aiptasia pulchella, and dinoflagellate symbiont, Symbiodinium sp. extract. Using HPLC-MS, fatty acids were separated and analyzed by tandem mass spectrometry in data-dependent acquisition mode. Neutral loss chromatograms for 78, 98, and 136 Da allowed the identification of long-chain fatty acids with five or more double bonds. On the basis of precursor ion m/z ratios, chain length and degree of unsaturation for these fatty acids were determined. The application of this technique to an Aiptasia sp.-Symbiodinium sp. lipid extract enabled the identification of the unusual, long-chain fatty acids 24:6, 26:6, 26:7, 28:7, and 28:8 during a single 40 min HPLC-MS analysis. PMID:22816781

  20. Production of long chain omega-3 fatty acids and carotenoids in tropical areas by a new heat-tolerant microalga Tetraselmis sp. DS3.

    Science.gov (United States)

    Tsai, Hsin-Pei; Chuang, Lu-Te; Chen, Ching-Nen Nathan

    2016-02-01

    Demand for long chain ω-3 fatty acids from non-fish source for vegetarians has increased recently. Marine microalgae are the primary producers of EPA/DHA and promising alternatives for fish oil. Tropical areas have abundant sunlight throughout the year for microalgal cultivation but this practice can be hindered by high temperature. Discovery of heat-tolerant marine microalgae that can synthesize EPA/DHA will solve these problems. A new species of microalga was isolated from a high temperature lagoon and identified as Tetraselmis sp. DS3. These cells could grow at 40 °C, the highest temperature for marine microalgal growth ever reported. Its ω-3 fatty acids and EPA accounted for 33 and 10% of total lipids, respectively, grown in nitrogen-depleted conditions. These cells also accumulated more than 5% β-carotene and 0.48% lutein in biomass. This new microalga can be cultivated for long chain ω-3 fatty acids and lutein production in the tropical areas. PMID:26304398

  1. Titration and exchange studies of liver fatty acid-binding protein with 13C-labeled long-chain fatty acids.

    Science.gov (United States)

    Wang, Hsin; He, Yan; Kroenke, Christopher D; Kodukula, Sarala; Storch, Judith; Palmer, Arthur G; Stark, Ruth E

    2002-04-30

    Uniformly (13)C-labeled long-chain fatty acids were used to probe ligand binding to rat liver fatty acid-binding protein (LFABP), an atypical member of the fatty acid-binding protein (FABP) family that binds more than one molecule of long-chain fatty acid, accommodates a variety of diverse ligands, and exhibits diffusion-mediated lipid transport to membranes. Two sets of (1)H-(13)C resonances were found in a titration series of NMR spectra for oleate-LFABP complexes, indicating that two molecules of the fatty acid are situated in the protein cavity. However, no distinct resonances were observed for the excess fatty acid in solution, suggesting that at least one ligand undergoes rapid exchange with oleate in the bulk solution. An exchange rate of 54 +/- 6 s(-1) between the two sets of resonances was measured directly using (13)C z,z-exchange spectroscopy. In light of these NMR measurements, possible molecular mechanisms for the ligand-exchange process are evaluated and implications for the anomalous fatty acid transport mechanism of LFABP are discussed. PMID:11969406

  2. Medium-chain versus long-chain triacylglycerol emulsion hydrolysis by lipoprotein lipase and hepatic lipase: Implications for the mechanisms of lipase action

    International Nuclear Information System (INIS)

    To explore how enzyme affinities and enzyme activities regulate hydrolysis of water-insoluble substrates, the authors compared hydrolysis of phospholipid-stabilized emulsions of medium-chain (MCT) versus long-chain triacylglycerols (LCT). Because substrate solubility at the emulsion surface might modulate rates of hydrolysis, the ability of egg yolk phosphatidylcholine to solubilize MCT was examined by NMR spectroscopy. Chemical shift measurements showed that 11 mol % of [13C]carbonyl enriched trioctanoin was incorporated into phospholipid vesicles as a surface component. Line widths of trioctanoin surface peaks were half that of LCT, and relaxation times, T1, were also shorter for trioctanoin, showing greater mobility for MCT in phospholipid. In assessing the effects of these differences in solubility on lipolysis, they found that both purified bovine milk lipoprotein lipase and human hepatic lipase hydrolyzed MCT at rates at least 2-fold higher than for LCT. Differences in affinity were also demonstrated in mixed incubations where increasing amounts of LCT emulsion resulted in decreased hydrolysis of MCT emulsions. These results suggest that despite lower enzyme affinity for MCT emulsions, shorter chain triacylglycerols are more readily hydrolyzed by lipoprotein and hepatic lipases than long-chain triacylglycerols because of greater MCT solubility and mobility at the emulsion-water interface

  3. Quenching Capabilities of Long-Chain Carotenoids in Light-Harvesting-2 Complexes from Rhodobacter sphaeroides with an Engineered Carotenoid Synthesis Pathway

    Science.gov (United States)

    2016-01-01

    Six light-harvesting-2 complexes (LH2) from genetically modified strains of the purple photosynthetic bacterium Rhodobacter (Rb.) sphaeroides were studied using static and ultrafast optical methods and resonance Raman spectroscopy. These strains were engineered to incorporate carotenoids for which the number of conjugated groups (N = NC=C + NC=O) varies from 9 to 15. The Rb. sphaeroides strains incorporate their native carotenoids spheroidene (N = 10) and spheroidenone (N = 11), as well as longer-chain analogues including spirilloxanthin (N = 13) and diketospirilloxantion (N = 15) normally found in Rhodospirillum rubrum. Measurements of the properties of the carotenoid first singlet excited state (S1) in antennas from the Rb. sphaeroides set show that carotenoid-bacteriochlorophyll a (BChl a) interactions are similar to those in LH2 complexes from various other bacterial species and thus are not significantly impacted by differences in polypeptide composition. Instead, variations in carotenoid-to-BChl a energy transfer are primarily regulated by the N-determined energy of the carotenoid S1 excited state, which for long-chain (N ≥ 13) carotenoids is not involved in energy transfer. Furthermore, the role of the long-chain carotenoids switches from a light-harvesting supporter (via energy transfer to BChl a) to a quencher of the BChl a S1 excited state B850*. This quenching is manifested as a substantial (∼2-fold) reduction of the B850* lifetime and the B850* fluorescence quantum yield for LH2 housing the longest carotenoids. PMID:27285777

  4. PREPARATION OF ALKYL HALIDES VIA ORGANOTELLURIUMS

    OpenAIRE

    チカマツ, キヨフミ; オオツボ, テツオ; オグラ, フミオ; ヤマグチ, ハチロウ; Kiyofumi, CHIKAMATSU; Tetsuo, OTSUBO; Fumio, OGURA; Hachiro, YAMAGUCHI

    1982-01-01

    The conversion of phenyltelluroalkanes to haloalkanes was studied in connection with the homologation of alkyl halides. Similar reactions of 1,1-bis(phenyltelluro)alkanes provided a new synthetic method of aldehydes.

  5. Thermally induced alkylation of diamond.

    Science.gov (United States)

    Hoeb, Marco; Auernhammer, Marianne; Schoell, Sebastian J; Brandt, Martin S; Garrido, Jose A; Stutzmann, Martin; Sharp, Ian D

    2010-12-21

    We present an approach for the thermally activated formation of alkene-derived self-assembled monolayers on oxygen-terminated single and polycrystalline diamond surfaces. Chemical modification of the oxygen and hydrogen plasma-treated samples was achieved by heating in 1-octadecene. The resulting layers were characterized using X-ray photoelectron spectroscopy, thermal desorption spectroscopy, atomic force microscopy, Fourier transform infrared spectroscopy, and water contact angle measurements. This investigation reveals that alkenes selectively attach to the oxygen-terminated sites via covalent C-O-C bonds. The hydrophilic oxygen-terminated diamond is rendered strongly hydrophobic following this reaction. The nature of the process limits the organic layer growth to a single monolayer, and FTIR measurements reveal that such monolayers are dense and well ordered. In contrast, hydrogen-terminated diamond sites remain unaffected by this process. This method is thus complementary to the UV-initiated reaction of alkenes with diamond, which exhibits the opposite reactivity contrast. Thermal alkylation increases the range of available diamond functionalization strategies and provides a means of straightforwardly forming single organic layers in order to engineer the surface properties of diamond. PMID:21090790

  6. Tripodal (N-alkylated) CMP(O) and malonamide ligands: synthesis, extraction of metal ions, and potentiometric studies

    Energy Technology Data Exchange (ETDEWEB)

    Janczewski, D.; Reinhoudt, D.N.; Verboom, W. [Twente Univ., Lab. of Supramolecular Chemistry and Technology, Mesa Research Institute for Nanotechnology, Enschede (Netherlands); Malinowska, E.; Pietrzak, M. [Warsaw Univ. of Technology, Dept. of Analytical Chemistry, Faculty of Chemistry (Poland); Hill, C.; Allignol, C. [CEA Valrho, 30 - Marcoule (France)

    2007-01-15

    Tripodal ligands build on the C-pivot (9b-e, 13b-d, and 17a-d) and tri-alkyl-benzene platforms (10a,b, 11, 12, 14a,b, and 18a,b) bearing (N-alkylated) carbamoyl-methyl-phosphine oxide (CMPO), carbamoyl-methyl-phosphonate (CMP), and malonamide moieties were synthesized. Extraction studies with Am{sup 3+} and Eu{sup 3+} show that in general there is a positive influence of the N-alkyl substituents in C-pivot CMP(O) ligands on the D(distribution) coefficients. The tri-alkyl-benzene CMPO ligands 10a,b, 11, and 12 have considerably larger D coefficients than the corresponding C-pivot analogues 9a-e, although hardly having any selectivity, while N-alkylation gives rise to smaller D coefficients. Although less effective the extraction behavior of the C-pivot CMP analogues 13b-d shows more or less the same trend as the corresponding CMPO ligands 9b-e upon substitution of the carboxamide N-atom with different alkyl chains. The different malonamide ligands 17a-d and 18a,b are bad extractants, while N-alkylation makes them even worse. Potentiometric studies of CMP(O) and malonamide ligands in polymeric membranes on Pb{sup 2+}, Cu{sup 2+}, Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, and K{sup +} salts revealed that N-alkyl substituents increase the stability constants of ion-ionophore complexes compared to unsubstituted ligands. In polymeric membrane electrodes the ligands induce a selectivity pattern that differs significantly from the so-called Hofmeister series, giving the highest selectivity coefficients for UO{sub 2}{sup 2+} among all examined cations (Pb{sup 2+}, Cu{sup 2+}, Ca{sup 2+}, Mg{sup 2+}, Na{sup +}, K{sup +}). (authors)

  7. Fish oil supplementation alters the plasma lipidomic profile and increases long-chain PUFAs of phospholipids and triglycerides in healthy subjects.

    Directory of Open Access Journals (Sweden)

    Inger Ottestad

    Full Text Available BACKGROUND: While beneficial health effects of fish and fish oil consumption are well documented, the incorporation of n-3 polyunsaturated fatty acids in plasma lipid classes is not completely understood. The aim of this study was to investigate the effect of fish oil supplementation on the plasma lipidomic profile in healthy subjects. METHODOLOGY/PRINCIPAL FINDINGS: In a double-blinded randomized controlled parallel-group study, healthy subjects received capsules containing either 8 g/d of fish oil (FO (1.6 g/d EPA+DHA (n = 16 or 8 g/d of high oleic sunflower oil (HOSO (n = 17 for seven weeks. During the first three weeks of intervention, the subjects completed a fully controlled diet period. BMI and total serum triglycerides, total-, LDL- and HDL-cholesterol were unchanged during the intervention period. Lipidomic analyses were performed using Ultra Performance Liquid Chromatography (UPLC coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (QTOFMS, where 568 lipids were detected and 260 identified. Both t-tests and Multi-Block Partial Least Square Regression (MBPLSR analysis were performed for analysing differences between the intervention groups. The intervention groups were well separated by the lipidomic data after three weeks of intervention. Several lipid classes such as phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine, sphingomyelin, phosphatidylserine, phosphatidylglycerol, and triglycerides contributed strongly to this separation. Twenty-three lipids were significantly decreased (FDR<0.05 in the FO group after three weeks compared with the HOSO group, whereas fifty-one were increased including selected phospholipids and triglycerides of long-chain polyunsaturated fatty acids. After seven weeks of intervention the two intervention groups showed similar grouping. CONCLUSIONS/SIGNIFICANCE: In healthy subjects, fish oil supplementation alters lipid metabolism and increases the

  8. The effect of polar end of long-chain fluorocarbon oligomers in promoting the superamphiphobic property over multi-scale rough Al alloy surfaces

    Science.gov (United States)

    Saifaldeen, Zubayda S.; Khedir, Khedir R.; Camci, Merve T.; Ucar, Ahmet; Suzer, Sefik; Karabacak, Tansel

    2016-08-01

    Rough structures with re-entrant property and their subsequent surface energy reduction with long-chain fluorocarbon oligomers are both critical in developing superamphiphobic (SAP, i.e. both super hydrophobic and superoleophobic) surfaces. However, morphology of the low-surface energy layer on a rough re-entrant substrate can strongly depend on the fluorocarbon oligomers used. In this study, the effect of polar end of different kinds of long-chain fluorocarbon oligomers in promoting a self-assembled monolayer with close packed molecules and robust adhesion on multi-scale rough Al alloy surfaces was investigated. Hierarchical Al alloy surfaces with microgrooves and nanograss structures were developed by a simple combination of one-directional mechanical sanding and post treatment in boiling de-ionized water (DIW). Three types of long-chain fluorocarbon oligomers of 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (PFDTS), 1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane (PFDCS), and perfluorooctanoic acid (PFOA) were chemically vaporized onto these rough Al alloy surfaces. The PFDCS exhibited the lowest surface free energy of less than 10 mN/m. The contact angle and sliding angle measurements for water, ethylene glycol, and peanut oil verified the SAP property of hierarchical rough Al alloy surfaces treated with alkylsilane oligomers (PFDTS, PFDCS). However, the hierarchical surfaces treated with fluorocarbon oligomer with polar acidic tail (PFOA) showed highly amphiphobic properties but could not reach the threshold for SAP. Chemical stability of the hierarchical Al alloy surfaces treated with the fluorocarbon oligomers was tested under the harsh conditions of ultra-sonication in acetone and annealing at high temperature after different treatment times. Contact angle measurements revealed the robustness of the alkylsilane oligomers and deterioration of the PFOA coating particularly for low surface tension liquids. The robust adhesion and close-packing of the alkylsilane

  9. Field trial evaluation of the accumulation of omega-3 long chain polyunsaturated fatty acids in transgenic Camelina sativa: Making fish oil substitutes in plants

    Directory of Open Access Journals (Sweden)

    Sarah Usher

    2015-12-01

    Full Text Available The global consumption of fish oils currently exceeds one million tonnes, with the natural de novo source of these important fatty acids forming the base of marine foodwebs. Here we describe the first field-based evaluation of a terrestrial source of these essential nutrients, synthesised in the seeds of transgenic Camelina sativa plants via the heterologous reconstitution of the omega-3 long chain polyunsaturated fatty acid biosynthetic pathway. Our data demonstrate the robust nature of this novel trait, and the feasibility of making fish oils in genetically modified crops. Moreover, to our knowledge, this is the most complex example of plant genetic engineering to undergo environmental release and field evaluation.

  10. Cancer Risk and Eicosanoid Production: Interaction between the Protective Effect of Long Chain Omega-3 Polyunsaturated Fatty Acid Intake and Genotype

    Science.gov (United States)

    Lenihan-Geels, Georgia; Bishop, Karen S.; Ferguson, Lynnette R.

    2016-01-01

    Dietary inclusion of fish and fish supplements as a means to improve cancer prognosis and prevent tumour growth is largely controversial. Long chain omega-3 polyunsaturated fatty acids (LCn-3 PUFA), eicosapentaenoic acid and docosahexaenoic acid, may modulate the production of inflammatory eicosanoids, thereby influencing local inflammatory status, which is important in cancer development. Although in vitro studies have demonstrated inhibition of tumour cell growth and proliferation by LCn-3 PUFA, results from human studies have been mainly inconsistent. Genes involved in the desaturation of fatty acids, as well as the genes encoding enzymes responsible for eicosanoid production, are known to be implicated in tumour development. This review discusses the current evidence for an interaction between genetic polymorphisms and dietary LCn-3 PUFA in the risk for breast, prostate and colorectal cancers, in regards to inflammation and eicosanoid synthesis. PMID:26891335

  11. Loss of long-chain acyl-CoA synthetase isoform 1 impairs cardiac autophagy and mitochondrial structure through mechanistic target of rapamycin complex 1 activation

    DEFF Research Database (Denmark)

    Grevengoed, Trisha J; Cooper, Daniel E; Young, Pamela A; Ellis, Jessica M; Coleman, Rosalind A

    2015-01-01

    protein and RNA synthesis and fatty acid metabolism, while decreasing autophagy. Compared with controls, Acsl1(T-/-) hearts contained 3 times more mitochondria with abnormal structure and displayed a 35-43% lower respiratory function. To study the effects of mTORC1 activation on mitochondrial structure......, which was likely caused by the 33-51% lower ATP synthase activity present in both vehicle- and rapamycin-treated Acsl1(T-/-) hearts. The turnover of microtubule associated protein light chain 3b in Acsl1(T-/-) hearts was 88% lower than controls, indicating a diminished rate of autophagy. Rapamycin...... treatment increased autophagy to a rate that was 3.1-fold higher than in controls, allowing the formation of autophagolysosomes and the clearance of damaged mitochondria. Thus, long-chain acyl-CoA synthetase isoform 1 (ACSL1) deficiency in the heart activated mTORC1, thereby inhibiting autophagy and...

  12. The effect of fatty acid positioning in dietary triacylglycerols and intake of long-chain n-3 polyunsaturated fatty acids on bone mineral accretion in growing piglets

    DEFF Research Database (Denmark)

    Ludvig, Stine Erbs; Andersen, Anders Daniel

    2013-01-01

    Long-chain n-3 PUFA (LCPUFA) and palmitate (16:0) positioning in the triacylglycerol (TAG) of infant formula may affect calcium-uptake which could affect bone health. We investigated if a human milk fat substitute (HMFS) with a modified TAG structure holding 16:0 predominantly in the sn-2-position...... computed tomography and mechanical strength. Bone mineral content (BMC) was higher in the FO compared to the SO-group (p=0.03). Despite similar weight gain in HMFS- and CONT-groups, body fat accumulation was higher with HMFS (p<0.001), and BMC, bone area (BA) and cortical BA in femur were lower (p=0.002, p...

  13. Long chain diol index (LDI) as an organic-based sea surface temperature proxy in the Korean East Sea (NW Pacific)

    Science.gov (United States)

    Gal, Jong-Ku; Kim, Jung-Hyun; Kang, Su-Jin; Lee, Dong-Hun; Shin, Kyung-Hoon

    2016-04-01

    Long chain diol index (LDI) was introduced as an organic-based sea surface temperature (SST) proxy. LDI is expressed as the C30 1,15-diol abundance relative to those of C28 1,13-, C30 1,13- and C30 1,15-diols. There were a few studies which accessed the potential of LDI based on the culture, core top sediments, suspended particulate organic matters, and down-core sediments. However it is still unknown about the source of the diols and robustness as the SST proxy in the various marine environments. In the current study, we examined the applicability of the LDI in the East Sea of Korea where productivity and thus sedimentation rates are high. We will compare the LDI data with those of alkenone-based UK'37 by analyzing two multicores covering the last 100 year.

  14. Management of familial Mediterranean fever by colchicine does not normalize the altered profile of microbial long chain fatty acids in the human metabolome

    Directory of Open Access Journals (Sweden)

    Zhanna eKtsoyan

    2013-01-01

    Full Text Available In our previous works we established that in an autoinflammatory condition, familial Mediterranean fever, the gut microbial diversity is specifically restructured, which also results in the altered profiles of microbial long chain fatty acids (LCFAs present in the systemic metabolome. The mainstream management of the disease is based on oral administration of colchicine to suppress clinical signs and extend remission periods and our aim was to determine whether this therapy normalizes the microbial LCFA profiles in the metabolome as well. Unexpectedly, the treatment does not normalize these profiles. Moreover, it results in the formation of new distinct microbial LCFA clusters, which are well separated from the corresponding values in healthy controls and FMF patients without the therapy. We hypothesize that the therapy alters the proinflammatory network specific for the disease, with the concomitant changes in gut microbiota and the corresponding microbial LCFAs in the metabolome.

  15. Oxidative stability of fish and algae oils containing long-chain polyunsaturated fatty acids in bulk and in oil-in-water emulsions

    DEFF Research Database (Denmark)

    Frankel, E.N.; Satue-Gracia, T.; Meyer, Anne Boye Strunge;

    2002-01-01

    from algae are unusually stable to oxidation, Addition of ethylenediaminetetraacetic acid (EDTA) prevented oxidation of both fish and algal oil emulsions without added iron and at low iron:EDTA molar concentrations. EDTA, however, promoted the oxidation of the corresponding emulsions that contained......The oxidative stability of long-chain polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA)-containing fish and algae oils varies widely according to their fatty acid composition, the physical and colloidal states of the lipids, the contents of tocopherols and other antioxidants, and the...... presence and activity of transition metals. Fish and algal oils were initially much more stable to oxidation in bulk systems than in the corresponding oil-in-water emulsions. The oxidative stability of emulsions cannot, therefore, be predicted on the basis of stability data obtained with bulk long...

  16. Long-chain fatty acids inhibition and adaptation process in anaerobic thermophilic digestion: Batch tests, microbial community structure and mathematical modelling

    DEFF Research Database (Denmark)

    Paltsi, Jordi; Illa, J.; Prenafeta-Boldu, F.X.;

    2010-01-01

    . Population profiles of eubacterial and archaeal 16S rDNA genes revealed that no significant shift on microbial community composition took place upon biomass exposure to LCFA. DNA sequencing of predominant DGGE bands showed close phylogenetic affinity to ribotypes characteristic from specific beta......Biomass samples taken during the continuous operation of thermophilic anaerobic digestors fed with manure and exposed to successive inhibitory pulses of long-chain fatty acids (LCFA) were characterized in terms of specific metabolic activities and 16S rDNA DGGE profiling of the microbial community...... structure. Improvement of hydrogenotrophic and acidogenic (beta-oxidation) activity rates was detected upon successive LCFA pulses, while different inhibition effects over specific anaerobic trophic groups were observed. Bioreactor recovery capacity and biomass adaptation to LCFA inhibition were verified...

  17. High-Yield Synthesis of Uniform Ag Nanowires with High Aspect Ratios by Introducing the Long-Chain PVP in an Improved Polyol Process

    Directory of Open Access Journals (Sweden)

    Jie-Jun Zhu

    2011-01-01

    Full Text Available Polyvinyl pyrrolidone (PVP with different molecular weights was used as capping agent to synthesize silver nanowires through a polyol process. The results indicated that the yields and aspect ratios of silver nanowires were controlled by the chain length of PVP and increased with increasing the molecular weight (MW of PVP. When the long-chain PVP-K90 (MW = 800,000 was used, the product was uniform in size and was dominated by nanowires with high aspect ratios. The growth mechanism of the nanowires was studied. It is proposed that the chemical adsorption of Ag+ on the PVP chains at the initial stage promotes the growth of Ag nanowires.

  18. Fish and long-chain n-3 polyunsaturated fatty acid intakes during pregnancy and risk of postpartum depression: a prospective study based on a large national birth cohort

    DEFF Research Database (Denmark)

    Strøm, Marin; Mortensen, Erik Lykke; Halldorsson, Thorhallur I;

    2009-01-01

    BACKGROUND: Mothers may be reluctant to receive medical treatment of postpartum depression (PPD), despite the detrimental consequences the disorder can impose on mother and child. Research on alternative methods of prevention and treatment of PPD is warranted. Previous studies have suggested that...... was linked to the Danish patient and prescription registries for data on clinically identified cases of depression up to 1 y postpartum. Intake of fish and n-3 PUFAs was assessed in midpregnancy with a food-frequency questionnaire. Admission to the hospital for PPD (PPD-admission) and prescription of...... long-chain n-3 polyunsaturated fatty acids (PUFAs) might have a beneficial effect on depression. OBJECTIVE: The objective was to explore the association between intake of fish and n-3 PUFAs during pregnancy and PPD in the Danish National Birth Cohort (DNBC). DESIGN: Exposure information from the DNBC...

  19. The roles of long-chain polyunsaturated fatty acids in pregnancy, lactation and infancy: review of current knowledge and consensus recommendations

    DEFF Research Database (Denmark)

    Koletzko, Berthold; Lien, Eric; Agostoni, Carlo;

    2008-01-01

    This paper reviews current knowledge on the role of the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (AA, 20:4n-6), in maternal and term infant nutrition as well as infant development. Consensus recommendations and practice guidelines...... consumption of oils rich in n-3 LC-PUFA during pregnancy reduces the risk for early premature birth. Pregnant and lactating women should aim to achieve an average daily intake of at least 200 mg DHA. For healthy term infants, we recommend and fully endorse breastfeeding, which supplies preformed LC-PUFA, as...... the preferred method of feeding. When breastfeeding is not possible, we recommend use of an infant formula providing DHA at levels between 0.2 and 0.5 weight percent of total fat, and with the minimum amount of AA equivalent to the contents of DHA. Dietary LC-PUFA supply should continue after the...

  20. Compound-specific carbon isotope compositions of individual long-chain n-alkanes in severe Asian dust episodes in the North China coast in 2002

    Institute of Scientific and Technical Information of China (English)

    GUO Zhigang; LI Juyuan; FENG Jialiang; FANG Ming; YANG Zuosheng

    2006-01-01

    The molecular compositions and compound-specific carbon isotope compositions of individual long-chain n-alkanes of atmospheric aerosols collected during two severe Asian dust episodes in Qingdao in spring of 2002 were analyzed using gas chromatography/mass spectrometry (GC/MS) and gas chromatography/isotope ratio mass spectrometry (GC/IRMS). Typical plant wax n-alkanes (C29 and C31) had lowerδ13C values than those from anthropogenic (engine exhaust) sources (C21―C23). The average δ13C value of plant wax n-alkane C29 in non-dust episode periods was -30.5‰ (-30.3‰― -31.9‰), while -31.3‰ (-31.1‰―-31.5‰) in dust episode periods; for C31, it was -31.4‰ (-31.1‰―-33.0‰) in non-dust episode periods, and -31.7‰ (-31.3‰―-32.6‰) in dust episode periods. Plant wax in the dust episode samples was mainly from herbaceous plants via long-range transport, while local plant wax was mainly from deciduous plants and woody plants. In North China coast, 83.3% of the plant wax in the severe dust episode samples was from C3 plants while 80.0% for the non-dust samples, indicating that plant wax transported to the northwestern Pacific Ocean by airborne dust from East Asia was mainly from C3 plants. The results suggest that the molecular and molecular-isotopic compositions of individual long-chain n-alkanes can, as an effective indicator, identify the terrestrial organic components in the dust from East Asia and sediments in the northwest Pacific Ocean.

  1. Semirational Protein Engineering of CYP153AM.aq. -CPRBM3 for Efficient Terminal Hydroxylation of Short- to Long-Chain Fatty Acids.

    Science.gov (United States)

    Notonier, Sandra; Gricman, Łukasz; Pleiss, Jürgen; Hauer, Bernhard

    2016-08-17

    The regioselective terminal hydroxylation of alkanes and fatty acids is of great interest in a variety of industrial applications, such as in cosmetics, in fine chemicals, and in the fragrance industry. The chemically challenging activation and oxidation of non-activated C-H bonds can be achieved with cytochrome P450 enzymes. CYP153AM.aq. -CPRBM3 is an artificial fusion construct consisting of the heme domain from Marinobacter aquaeolei and the reductase domain of CYP102A1 from Bacillus megaterium. It has the ability to hydroxylate medium- and long-chain fatty acids selectively at their terminal positions. However, the activity of this interesting P450 construct needs to be improved for applications in industrial processes. For this purpose, the design of mutant libraries including two consecutive steps of mutagenesis is demonstrated. Targeted positions and residues chosen for substitution were based on semi-rational protein design after creation of a homology model of the heme domain of CYP153AM.aq. , sequence alignments, and docking studies. Site-directed mutagenesis was the preferred method employed to address positions within the binding pocket, whereas diversity was created with the aid of a degenerate codon for amino acids located at the substrate entrance channel. Combining the successful variants led to the identification of a double variant-G307A/S233G-that showed alterations of one position within the binding pocket and one position located in the substrate access channel. This double variant showed twofold increased activity relative to the wild type for the terminal hydroxylation of medium-chain-length fatty acids. This variant furthermore showed improved activity towards short- and long-chain fatty acids and enhanced stability in the presence of higher concentrations of fatty acids. PMID:27251775

  2. High content of long-chain n-3 polyunsaturated fatty acids in red blood cells of Kenyan Maasai despite low dietary intake

    Directory of Open Access Journals (Sweden)

    Kiage-Mokua Beatrice N

    2011-08-01

    Full Text Available Abstract Background Increasing land restrictions and a reduced livestock-to-human ratio during the 20th century led the Maasai to lead a more sedentary, market-orientated lifestyle. Although plant-derived food nowadays contributes substantially to their diet, dairy products being high in saturated fatty acids (SFA and low in polyunsaturated fatty acids (PUFA still are an important energy source. Since reliable data regarding the Maasai diet date back to the 1980s, the study objective was to document current diet practices in a Kenyan Maasai community and to investigate the fatty acid distribution in diet and red blood cells. Methods A cross-sectional study was conducted among 26 Maasai (20 women, 6 men from Loodokilani, Kajiado District, Kenya. Food intake was described by the subjects via 24-h recall, and both food and blood samples were analysed. Results Two main foods - milk and ugali - constituted the Maasai diet in this region. A total of 0.9 L of milk and 0.6 kg of ugali were consumed per person and day to yield an energy intake of 7.6 MJ/d per person. A major proportion of ingested food contributing 58.3% to the total dietary energy (en% was plant-derived, followed by dairy products representing 41.1 en%. Fat consumed (30.5 en% was high in SFA (63.8% and low in PUFA (9.2%. Long-chain n-3 PUFA (EPA, DPA and DHA made up only 0.15% of the ingested fatty acids, but 5.9% of red blood cell fatty acids. Conclusion The study indicates the Maasai diet is rich in SFA and low in PUFA. Nevertheless, red blood cells are composed of comparable proportions of long-chain n-3 PUFA to populations consuming higher amounts of this fatty acid group.

  3. Two very long chain fatty acid acyl-CoA synthetase genes, acs-20 and acs-22, have roles in the cuticle surface barrier in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Eriko Kage-Nakadai

    Full Text Available In multicellular organisms, the surface barrier is essential for maintaining the internal environment. In mammals, the barrier is the stratum corneum. Fatty acid transport protein 4 (FATP4 is a key factor involved in forming the stratum corneum barrier. Mice lacking Fatp4 display early neonatal lethality with features such as tight, thick, and shiny skin, and a defective skin barrier. These symptoms are strikingly similar to those of a human skin disease called restrictive dermopathy. FATP4 is a member of the FATP family that possesses acyl-CoA synthetase activity for very long chain fatty acids. How Fatp4 contributes to skin barrier function, however, remains to be elucidated. In the present study, we characterized two Caenorhabditis elegans genes, acs-20 and acs-22, that are homologous to mammalian FATPs. Animals with mutant acs-20 exhibited defects in the cuticle barrier, which normally prevents the penetration of small molecules. acs-20 mutant animals also exhibited abnormalities in the cuticle structure, but not in epidermal cell fate or cell integrity. The acs-22 mutants rarely showed a barrier defect, whereas acs-20;acs-22 double mutants had severely disrupted barrier function. Moreover, the barrier defects of acs-20 and acs-20;acs-22 mutants were rescued by acs-20, acs-22, or human Fatp4 transgenes. We further demonstrated that the incorporation of exogenous very long chain fatty acids into sphingomyelin was reduced in acs-20 and acs-22 mutants. These findings indicate that C. elegans Fatp4 homologue(s have a crucial role in the surface barrier function and this model might be useful for studying the fundamental molecular mechanisms underlying human skin barrier and relevant diseases.

  4. Long-chain polyunsaturated fatty acid biosynthesis in the euryhaline herbivorous teleost Scatophagus argus: Functional characterization, tissue expression and nutritional regulation of two fatty acyl elongases.

    Science.gov (United States)

    Xie, Dizhi; Chen, Fang; Lin, Siyuan; You, Cuihong; Wang, Shuqi; Zhang, Qinghao; Monroig, Óscar; Tocher, Douglas R; Li, Yuanyou

    2016-08-01

    Both the spotted scat Scatophagus argus and rabbitfish Siganus canaliculatus belong to the few cultured herbivorous marine teleost, however, their fatty acyl desaturase (Fad) system involved in long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis is different. The S. argus has a △6 Fad, while the rabbitfish has △4 and △6/△5 Fads, which were the first report in vertebrate and marine teleost, respectively. In order to compare the characteristics of elongases of very long-chain fatty acids (Elovl) between them, two Elovl cDNAs were cloned from S. argus in the present study. One has 885bp of open read fragment (ORF) encoding a protein with 294 amino acid (aa) showing Elovl5 activity functionally characterized by heterologous expression in yeast, which was primarily active for the elongation of C18 and C20 PUFAs. The other has 915bp of ORF coding for a 305 aa protein showing Elovl4 activity, which was more efficient in the elongation of C20 and C22 PUFAs. Tissue distribution analyses by RT-PCR showed that elovl5 was highly expressed in the liver compared to other tissues determined, whereas elovl4 transcripts were only detected in the eye. The expression of elovl5 and elovl4 were significantly affected by dietary fatty acid composition, with highest expression of mRNA in the liver and eye of fish fed a diet with an 18:3n-3/18:2n-6 ratio of 1.7:1. These results indicated that the S. argus has a similar Elovl system in the LC-PUFA biosynthetic pathway to that of rabbitfish although their Fad system was different, suggesting that the diversification of fish LC-PUFA biosynthesis specificities is more associated with its Fad system. These new insights expand our knowledge and understanding of the molecular basis and regulation of LC-PUFA biosynthesis in fish. PMID:27050407

  5. Liquid-phase alkylation of Assam (Baragolai) coal

    Energy Technology Data Exchange (ETDEWEB)

    Kalra, R.L.; Choudhury, R.; Sarkar, M.K.

    1982-12-01

    Liquid paraffin which consists of a large number of alkylated aliphatics and aromatics seems to be acting as an alkyl group transfer medium to receptive complexes like coal. The alkyl group receptive spots could be created in the coal complex by treatment with molten alkalis like sodium or potassium hydroxide. By repeating extractions of fresh coal with the same volume of liquid paraffin on a laboratory scale it was found that a stage was reached when liquid paraffin became rich enough in alkyl groups to become an alkyl group donor. This suggests a method for liquid phase alkylation of coal. (3 refs.)

  6. Platelet-activating factor acetylhydrolase: selective inhibition by potent n-alkyl methylphosphonofluoridates

    International Nuclear Information System (INIS)

    Platelet-activating factor (PAF) is a potent endogenous phospholipid modulator of diverse biological activities, including inflammation and shock. PAF levels are primarily regulated by PAF acetylhydrolases (PAF-AHs). These enzymes are candidate secondary targets of organophosphorus (OP) pesticides and related toxicants. Previously known OP inhibitors of other serine hydrolases were tested with PAF-AH from mouse brain and testes of established functional importance compared with the structurally different human plasma enzyme. Several key OP pesticides and their oxon metabolites were very poor inhibitors of mouse brain and human plasma PAF-AH in vitro but moderately active for mouse brain and blood PAF-AH in vivo (e.g., tribufos defoliant and profenofos insecticide, presumably following oxidative bioactivation). OP compounds were then designed for maximum in vitro potency and selectivity for mouse brain PAF-AH vs. acetylcholinesterase (AChE). Lead compounds were found in a series of benzodioxaphosphorin 2-oxides. Ultrahigh potency and selectivity were achieved with n-alkyl methylphosphonofluoridates (long-chain sarin analogs): mouse brain and testes IC50 ≤ 5 nM for C8-C18 analogs and 0.1-0.6 nM for C13 and C14 compounds; human plasma IC50 ≤ 2 nM for C13-C18 analogs. AChE inhibitory potency decreased as chain length increased with maximum brain PAF-AH/AChE selectivity (>3000-fold) for C13-C18 compounds. The toxicity of i.p.-administered PAF (LD50 ca. 0.5 mg/kg) was increased less than 2-fold by pretreatment with tribufos or the C13 n-alkyl methylphosphonofluoridate. These studies with a mouse model indicate that PAF-AH is not a major secondary target of OP pesticide poisoning. The optimized PAF-AH inhibitors may facilitate investigations on other aspects of PAF metabolism and action

  7. Hydrogen-bonded complexes resulting from the interaction of alkylated barbituric acid and 2,6-diamidopyridine derivatives

    Science.gov (United States)

    Sideratou, Z.; Tsiourvas, D.; Paleos, C. M.; Peppas, E.; Anastassopoulou, J.; Theophanides, T.

    1999-06-01

    In the present study a hydrophilic or a lipophilic alkylated barbituric acid derivative was allowed to interact in the melt and in solution with a complementary series of alkylated diamidopyridine derivatives, both hydrophilic or lipophilic. The interaction between the molecules was mainly studied by FT-IR spectroscopy. Phase transitions of reaction mixtures were studied with polarized optical microscopy and differential scanning calorimetry. It was found that the molecular recognition of the interacting components is only effective between the molecularly compatible ones. Specifically, employing Methods I and II, (see text) the short chain derivatives form 1 : 1 complexes whereas the long-chain derivatives are only partially complexed. Derivatives of dissimilar lipophilicity do not form complexes employing the same methods. However, comparing the two methods, complexation is more effective employing Method II. The induction of molecular recognition in the presence of an apolar solvent is enhanced in solution, Method III. The equilibrium which was established in solution is shifted to different directions during the evaporation step (Method II), leading either to the formation of complexes or to self-association.

  8. Silver-catalyzed coupling reactions of alkyl halides with indenyllithiums

    OpenAIRE

    Someya, Hidenori; Yorimitsu, Hideki; Oshima, Koichiro

    2010-01-01

    Coupling reactions of tertiary and secondary alkyl halides with indenyllithiums proceeded effectively in the presence of a catalytic amount of silver bromide to provide tertiary- and secondary-alkyl-substituted indene derivatives in good yields.

  9. Outlook for the U.S. alkylation industry

    International Nuclear Information System (INIS)

    Alkylation has long been recognized in the refining industry as one of the best options to convert refinery olefins into valuable, clean, high octane blending components. In fact, refinery alkylation is a preferred source of blending stocks for reformulated gasoline. However, the hydrofluoric acid (HF) alkylation process and, to a lesser extent, the sulfuric acid (SA) process have come under increasing pressure in the US due to safety and environmental concerns. This paper examines the current outlook for the US alkylation industry including: key trends and driving forces in the industry, the impact of environmental issues on both HF and SA alkylation, US alkylation supply/demand forecast including the outlook for oxygenates, how US refines will respond to the increased demand and restricted supply for alkylates, and the outlook for new solid acid alkylation (SAC) technology

  10. Restoration of bearings

    Science.gov (United States)

    Parker, R. J.; Zaretsky, E. V.; Hanau, H.

    1977-01-01

    Process consisting of grinding raceways to oversize but original quality condition and installing new oversize balls or bearings restores wornout ball and roller bearings to original quality, thereby doubling their operating life. Evaluations reveal process results in restoration of 90% of replaced bearings at less than 50% of new-bearing costs.

  11. Passive magnetic bearing configurations

    Science.gov (United States)

    Post, Richard F.

    2011-01-25

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  12. Root uptake and translocation of perfluorinated alkyl acids by three hydroponically grown crops.

    Science.gov (United States)

    Felizeter, Sebastian; McLachlan, Michael S; De Voogt, Pim

    2014-04-16

    Tomato, cabbage, and zucchini plants were grown hydroponically in a greenhouse. They were exposed to 14 perfluorinated alkyl acids (PFAAs) at four different concentrations via the nutrient solution. At maturity the plants were harvested, and the roots, stems, leaves, twigs (where applicable), and edible parts (tomatoes, cabbage head, zucchinis) were analyzed separately. Uptake and transfer factors were calculated for all plant parts to assess PFAA translocation and distribution within the plants. Root concentration factors were highest for long-chain PFAAs (>C11) in all three plant species, but these chemicals were not found in the edible parts. All other PFAAs were present in all above-ground plant parts, with transpiration stream concentration factors (TSCFs) of 0.05-0.25. These PFAAs are taken up with the transpiration stream and accumulate primarily in the leaves. Although some systematic differences were observed, overall their uptake from nutrient solution to roots and their further distribution within the plants were similar between plant species and among PFAAs. PMID:24646206

  13. Maintenance Free Bearings

    OpenAIRE

    S. M. Muzakkir & Harish Hirani

    2015-01-01

    In the present research work the need of a Maintenance Free Bearings (MFB) is established. The paper presents preliminary friction calculations to highlight the ways to achieve maintenance free bearings. The existing technologies of well established maintenance free bearings are described. The hybridization of bearing technologies to achieve low cost maintenance free bearings has been exemplified. Finally a combination of passive magnetic repulsion and hydrodynamics ha...

  14. 40 CFR 721.575 - Substituted alkyl halide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  15. 40 CFR 721.10053 - Alkyl silane methacrylate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl silane methacrylate (generic... Specific Chemical Substances § 721.10053 Alkyl silane methacrylate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkyl...

  16. The Synthesis of 6-Alkyl-5-Fluorouracil Derivatives

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    6-alkyl-5-fluorouracil derivatives (5a~5f) were synthesized by facile alkylation of lithiation of 5-fluorouracil derivatives with mthyl iodide (MeI) or alkyl trifluoromethanesulfonate (ROTf) in yield of 42~58%. We found that the methylated product was ethyl-substituted derivatives, not methyl-substituted derivatives.

  17. IONIC LIQUID-CATALYZED ALKYLATION OF ISOBUTANE WITH 2-BUTENE

    Science.gov (United States)

    A detailed study of the alkylation of isobutane with 2-butene in ionic liquid media has been conducted using 1-alkyl-3-methylimidazolium halides?aluminum chloride encompassing various alkyl groups (butyl-, hexyl-, and octyl-) and halides (Cl, Br, and I) on its cations and anions,...

  18. High levels of both n-3 and n-6 long-chain polyunsaturated fatty acids in cord serum phospholipids predict allergy development.

    Directory of Open Access Journals (Sweden)

    Malin Barman

    Full Text Available BACKGROUND: Long-chain polyunsaturated fatty acids (LCPUFAs reduce T-cell activation and dampen inflammation. They might thereby counteract the neonatal immune activation and hamper normal tolerance development to harmless environmental antigens. We investigated whether fatty acid composition of cord serum phospholipids affects allergy development up to age 13 years. METHODS: From a population-based birth-cohort born in 1996/7 and followed until 13 years of age (n = 794, we selected cases with atopic eczema (n = 37 or respiratory allergy (n = 44, as well as non-allergic non-sensitized controls (n = 48 based on diagnosis at 13 years of age. Cord and maternal sera obtained at delivery from cases and controls were analysed for proportions of saturated, monounsaturated and polyunsaturated fatty acids among serum phospholipids. RESULTS: The cord serum phospholipids from subject who later developed either respiratory allergy or atopic eczema had significantly higher proportions of 5/8 LCPUFA species, as well as total n-3 LCPUFA, total n-6 LCPUFA and total LCPUFA compared to cord serum phospholipids from controls who did not develop allergy (P<0.001 for all comparisons. Conversely, individuals later developing allergy had lower proportion of the monounsaturated fatty acid 18∶1n-9 as well as total MUFA (p<0.001 among cord serum phospholipids. The risk of respiratory allergy at age 13 increased linearly with the proportion of n-3 LCPUFA (Ptrend<0.001, n-6 LCPUFA (Ptrend = 0.001, and total LCPUFA (Ptrend<0.001 and decreased linearly with the proportions of total MUFA (Ptrend = 0.025 in cord serum phospholipids. Furthermore, Kaplan-Meier estimates of allergy development demonstrated that total LCPUFA proportion in cord serum phospholipids was significantly associated with respiratory allergy (P = 0.008 and sensitization (P = 0.002, after control for sex and parental allergy. CONCLUSION: A high proportion of long-chain

  19. Long-chain acyl-CoA synthetase 2 knockdown leads to decreased fatty acid oxidation in fat body and reduced reproductive capacity in the insect Rhodnius prolixus.

    Science.gov (United States)

    Alves-Bezerra, Michele; Klett, Eric L; De Paula, Iron F; Ramos, Isabela B; Coleman, Rosalind A; Gondim, Katia C

    2016-07-01

    Long-chain acyl-CoA esters are important intermediates in lipid metabolism and are synthesized from fatty acids by long-chain acyl-CoA synthetases (ACSL). The hematophagous insect Rhodnius prolixus, a vector of Chagas' disease, produces glycerolipids in the midgut after a blood meal, which are stored as triacylglycerol in the fat body and eggs. We identified twenty acyl-CoA synthetase genes in R. prolixus, two encoding ACSL isoforms (RhoprAcsl1 and RhoprAcsl2). RhoprAcsl1 transcripts increased in posterior midgut on the second day after feeding, and RhoprAcsl2 was highly transcribed on the tenth day. Both enzymes were expressed in Escherichia coli. Recombinant RhoprACSL1 and RhoprACSL2 had broad pH optima (7.5-9.5 and 6.5-9.5, respectively), were inhibited by triacsin C, and were rosiglitazone-insensitive. Both showed similar apparent Km for palmitic and oleic acid (2-6μM), but different Km for arachidonic acid (0.5 and 6μM for RhoprACSL1-Flag and RhoprACSL2-Flag, respectively). The knockdown of RhoprAcsl1 did not result in noticeable phenotypes. However, RhoprACSL2 deficient insects exhibited a 2.5-fold increase in triacylglycerol content in the fat body, and 90% decrease in fatty acid β-oxidation. RhoprAcsl2 knockdown also resulted in 20% increase in lifespan, delayed digestion, 30% reduced oviposition, and 50% reduction in egg hatching. Laid eggs and hatched nymphs showed remarkable alterations in morphology. In summary, R. prolixus ACSL isoforms have distinct roles on lipid metabolism. Although RhoprACSL1 functions remain unclear, we propose that RhoprACSL2 is the main contributor for the formation of the intracellular acyl-CoA pool channeled for β-oxidation in the fat body, and is also required for normal reproduction. PMID:27091636

  20. The change in cholesterol content of long chain fatty acid egg during processing and its influence to the Rattus norvegicus L. blood cholesterol content

    Directory of Open Access Journals (Sweden)

    Dini Hardini

    2006-12-01

    Full Text Available Egg containing long chain unsaturated fatty acids is a functional food, because it is highly nutritious and could prevent diseases, (omega 3 and 6 such as coronary heart attack. The research was aimed to measure the change of egg cholesterol content during proceesing: frying, oiless frying and boiling and their influence to the blood plasma cholesterol of normal and hypercholesterolemia rat. Seven treatments of egg yolk were frying at 170°C for 3 min (welldone = GM, and 1min (half medium fried = GSM using deep fryer , oilless frying at 70°C for10 min (fried = TM, and 6 min (half fried = TSM using Teflon pan, and boiling at 100°C for 10’ (boiled = RM dan 4 min (half boiled = RSM using pan provided with thermoregulator and a fresh omega egg as a control. The Completely randomized design was apllied for 4 weeks research period. The data from different treatments were analyzed by Orthogonal Contrast. Fifty 2 months old male rats Rattus norvegicus L. separated in 2 groups; normal and hypercholesterolemia (blood cholesterol > 200 mg dl-1. The rats were placed in individual cage, fed 15 g h-1 day-1 and water drinking ad libitum. The ration was composed of 90% basal commercial feed BR II and 10% egg yolk was given to each animal at 20% of live weight. Factorial 2 x 7 of completely randomized design was applied. The data were analyzed by ANOVA and Duncan’s Multiple Range Test. Processsing method of egg affected to cholesterol content of egg, The lowest and the highest cholesterol contents were observed in TSM (0.30 g/100g and GM (0.37 g/100g, respectively. Biological test using Rattus norvegicus L rat showed that either fresh and processed long chain fatty acid egg decreased plasma cholesterol. The highest and the lowest decreases of cholesterol content were found in the group consumed RSM (8.64% and GM (1.77% for normal rat; and control (46.3% followed by RSM (44.53% and GM (24.86%, respectively. To maintain normal cholesterol and decrease

  1. The associations between serum adiponectin, leptin, C-reactive protein, insulin, and serum long-chain omega-3 fatty acids in Labrador Retrievers

    Directory of Open Access Journals (Sweden)

    Streeter RM

    2015-04-01

    Full Text Available Renee M Streeter,1 Angela M Struble,1 Sabine Mann,2 Daryl V Nydam,2 John E Bauer,3 Marta G Castelhano,1 Rory J Todhunter,1 Bethany P Cummings,4 Joseph J Wakshlag11Department of Clinical Sciences, 2Department of Population Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA; 3Department of Clinical Sciences, Texas A&M University, College Station, TX, USA; 4Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USAAbstract: Obesity has been associated with an increased inflammatory response and insulin resistance due to adipose tissue–derived adipokines and increases in C-reactive protein (CRP. Dogs appear to be similar to other species with the exception of adiponectin, which might not be affected by obesity status. Serum long-chain polyunsaturated fatty acid concentrations have been positively and negatively associated with serum adipokines. The aim of the study was to examine the relationship between leptin, CRP, adiponectin, and insulin to body condition score (BCS and to the long-chain omega-3 fatty acids in serum lipoproteins, including alpha-linolenic acid, eicosapentaenoic acid (EPA, docosapentanenoic acid (DPA, and docosahexaenoic acid (DHA as a reflection of dietary omega-3 status in the Labrador Retriever. Seventy-seven Labrador Retrievers were evaluated for BCS, percent fasting serum lipoprotein fatty acid concentrations, as well as serum leptin, adiponectin, insulin, and CRP. A multivariable general linear regression model was constructed to examine the association between the dependent variables leptin, CRP, adiponectin, and insulin and the predictor variables of BCS, age, and sex, as well as concentrations of alpha-linolenic acid, EPA, DHA, and DPA. Adiponectin concentration was positively associated with age (P<0.0008, EPA (P=0.027 and negatively associated with DHA (P=0.008. Leptin concentration was positively associated with an increased DHA (P=0.009, BCS (P

  2. Reduced levels of hydroxylated, polyunsaturated ultra long-chain fatty acids in the serum of colorectal cancer patients: implications for early screening and detection

    Directory of Open Access Journals (Sweden)

    Takemasa Ichiro

    2010-02-01

    Full Text Available Abstract Background There are currently no accurate serum markers for detecting early risk of colorectal cancer (CRC. We therefore developed a non-targeted metabolomics technology to analyse the serum of pre-treatment CRC patients in order to discover putative metabolic markers associated with CRC. Using tandem-mass spectrometry (MS/MS high throughput MS technology we evaluated the utility of selected markers and this technology for discriminating between CRC and healthy subjects. Methods Biomarker discovery was performed using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS. Comprehensive metabolic profiles of CRC patients and controls from three independent populations from different continents (USA and Japan; total n = 222 were obtained and the best inter-study biomarkers determined. The structural characterization of these and related markers was performed using liquid chromatography (LC MS/MS and nuclear magnetic resonance technologies. Clinical utility evaluations were performed using a targeted high-throughput triple-quadrupole multiple reaction monitoring (TQ-MRM method for three biomarkers in two further independent populations from the USA and Japan (total n = 220. Results Comprehensive metabolomic analyses revealed significantly reduced levels of 28-36 carbon-containing hydroxylated polyunsaturated ultra long-chain fatty-acids in all three independent cohorts of CRC patient samples relative to controls. Structure elucidation studies on the C28 molecules revealed two families harbouring specifically two or three hydroxyl substitutions and varying degrees of unsaturation. The TQ-MRM method successfully validated the FTICR-MS results in two further independent studies. In total, biomarkers in five independent populations across two continental regions were evaluated (three populations by FTICR-MS and two by TQ-MRM. The resultant receiver-operator characteristic curve AUCs ranged from 0.85 to 0.98 (average = 0.91

  3. Synthesis and characterization of chitosan alkyl urea.

    Science.gov (United States)

    Wang, Jing; Jiang, Ji-Zhou; Chen, Wei; Bai, Zheng-Wu

    2016-07-10

    Chitosan is a versatile material employed for various purposes in many fields including the development of chiral stationary phases for enantioseparation. Chitosan alkyl urea is a kind of intermediate used to prepare enantioseparation materials. In order to synthesize the intermediates, in the present work, a new way to prepare chitosan alkyl urea has been established: chitosan was first reacted with methyl chloroformate yielding N-methoxyformylated chitosan, which was then converted to chitosan alkyl urea through amine-ester exchange reaction. With a large excess of methyl chloroformate and primary amine of low stereohindrance, the amino group in chitosan could be almost completely converted to ureido group. The as-prepared chitosan alkyl urea derivatives were characterized by IR, (1)H NMR, (13)C NMR,(1)H-(1)H COSY and (1)H-(13)C HSQC NMR spectra. The chemical shifts of hydrogen and carbon atoms of glucose unit were assigned. It was found that the degree of substitution was obviously lower if cyclopropyl amine, aniline, tert-butyl amine and diethyl amine were used as reactants for the amine-ester exchange reaction. The reason was explained with the aid of theoretical calculations. PMID:27106154

  4. Polypyrrole Doped with Alkyl Benzene Sulphonates

    DEFF Research Database (Denmark)

    Bay, Lasse; Mogensen, Naja; Skaarup, Steen;

    2002-01-01

    The properties of polypyrrole (PPy) are to a large extent determined by the condition of synthesis and especially by the counterion incorporated as dopant during synthesis. In this work, PPy doped with different alkyl benzenesulfonates are compared. The polymer films are prepared by constant curr...

  5. Amphiphilic ruthenium bipyridine complex containing long-chain azopyridine group and the mechanism of electron transfer in Langmuir-Blodgett films

    International Nuclear Information System (INIS)

    We synthesized the amphiphilic bis(bipyridine) ruthenium complex [Ru(bipy)2Cl(L)]+ (bipy= 2,2′-bipyridine, L = 4-(4-dodecyloxyphenylazo) pyridine). The long-chain ligand contributed to the self-assembly of the complex at the liquid-air interface, enabling its deposition by the Langmuir-Blodgett technique. The UV-vis, Raman, and specular reflectance FTIR spectroscopies revealed the molecular organization in the LB films: in the free ligand LB film the alkoxyphenylazopyridine species were oriented in parallel to each other and parallel to the normal plane of the substrate, whilst in the ruthenium complex film the alkoxyphenylazopyridine species were oriented in parallel to each other and perpendicular to the normal plane of the substrate. We then prepared multilayer films consisting of layers of ligand L supporting a monolayer of the ruthenium complex and characterized them by electrochemistry. This hybrid film structure led to optimal orientation of the ruthenium centers for electrochemical response. The results indicated that the phenylazo low-lying π-orbital participated in the hopping mechanism that mediated the electron transfer in the LB films with few molecular layers

  6. Gas chromatography-mass spectrometric analysis of bonded long chain fatty acids in a single zebrafish egg by ultrasound-assisted one-step transmethylation and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianjian; Yue Yingxia; Li Tingting; Hu Xuejiao [Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei 430079 (China); Zhong Hongying, E-mail: hyzhong@mail.ccnu.edu.cn [Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, Hubei 430079 (China)

    2009-09-21

    Changes in the level of lipid composition in a single zebrafish egg have been involved in biological responses to chemical exposures. In this paper, an one-step transmethylation of lipids and simultaneous extraction of resultant fatty acid methyl esters followed by gas chromatography-mass spectrometric analysis was developed for the identification of bonded long chain fatty acids in a single zebrafish egg. The efficiency of transmethylation under different experimental conditions has been investigated. Dried egg homogenates were directly mixed with either 0.5 M NaOH or 1% H{sub 2}SO{sub 4} or 4% HCl solution of methanol and then an n-hexane solution was added on the top. Ultrasonication of this immiscible liquid-liquid-solid system produces high velocity impacts between solid particles and liquid phases and thus promotes mass transfer among phases. It was demonstrated that ultrasound irradiation has strong effect on the alkaline-catalyzed transmethylation of lipids but cannot significantly change the acid-catalyzed transmethylation of lipids. With the aid of ultrasonication, transmethylation can be combined with simultaneous extraction of the resultant fatty acid methyl esters into n-hexane phase. This approach simplifies the sample preparation procedure, shortens the reaction time but improves the efficiency of the transmethylation of lipids and reduces sample losses, especially for small size samples. It has been applied to determine bonded fatty acids in a single zebrafish egg. In total, 28 fatty acids from a single zebrafish egg have been identified reproducibly.

  7. Gas chromatography-mass spectrometric analysis of bonded long chain fatty acids in a single zebrafish egg by ultrasound-assisted one-step transmethylation and extraction

    International Nuclear Information System (INIS)

    Changes in the level of lipid composition in a single zebrafish egg have been involved in biological responses to chemical exposures. In this paper, an one-step transmethylation of lipids and simultaneous extraction of resultant fatty acid methyl esters followed by gas chromatography-mass spectrometric analysis was developed for the identification of bonded long chain fatty acids in a single zebrafish egg. The efficiency of transmethylation under different experimental conditions has been investigated. Dried egg homogenates were directly mixed with either 0.5 M NaOH or 1% H2SO4 or 4% HCl solution of methanol and then an n-hexane solution was added on the top. Ultrasonication of this immiscible liquid-liquid-solid system produces high velocity impacts between solid particles and liquid phases and thus promotes mass transfer among phases. It was demonstrated that ultrasound irradiation has strong effect on the alkaline-catalyzed transmethylation of lipids but cannot significantly change the acid-catalyzed transmethylation of lipids. With the aid of ultrasonication, transmethylation can be combined with simultaneous extraction of the resultant fatty acid methyl esters into n-hexane phase. This approach simplifies the sample preparation procedure, shortens the reaction time but improves the efficiency of the transmethylation of lipids and reduces sample losses, especially for small size samples. It has been applied to determine bonded fatty acids in a single zebrafish egg. In total, 28 fatty acids from a single zebrafish egg have been identified reproducibly.

  8. Plant and animal glycolate oxidases have a common eukaryotic ancestor and convergently duplicated to evolve long-chain 2-hydroxy acid oxidases.

    Science.gov (United States)

    Esser, Christian; Kuhn, Anke; Groth, Georg; Lercher, Martin J; Maurino, Veronica G

    2014-05-01

    Glycolate oxidase (GOX) is a crucial enzyme of plant photorespiration. The encoding gene is thought to have originated from endosymbiotic gene transfer between the eukaryotic host and the cyanobacterial endosymbiont at the base of plantae. However, animals also possess GOX activities. Plant and animal GOX belong to the gene family of (L)-2-hydroxyacid-oxidases ((L)-2-HAOX). We find that all (L)-2-HAOX proteins in animals and archaeplastida go back to one ancestral eukaryotic sequence; the sole exceptions are green algae of the chlorophyta lineage. Chlorophyta replaced the ancestral eukaryotic (L)-2-HAOX with a bacterial ortholog, a lactate oxidase that may have been obtained through the primary endosymbiosis at the base of plantae; independent losses of this gene may explain its absence in other algal lineages (glaucophyta, rhodophyta, and charophyta). We also show that in addition to GOX, plants possess (L)-2-HAOX proteins with different specificities for medium- and long-chain hydroxyacids (lHAOX), likely involved in fatty acid and protein catabolism. Vertebrates possess lHAOX proteins acting on similar substrates as plant lHAOX; however, the existence of GOX and lHAOX subfamilies in both plants and animals is not due to shared ancestry but is the result of convergent evolution in the two most complex eukaryotic lineages. On the basis of targeting sequences and predicted substrate specificities, we conclude that the biological role of plantae (L)-2-HAOX in photorespiration evolved by co-opting an existing peroxisomal protein. PMID:24408912

  9. Thermophilic anaerobic co-digestion of sewage sludge with grease waste: Effect of long chain fatty acids in the methane yield and its dewatering properties

    International Nuclear Information System (INIS)

    Highlights: • Thermophilic anaerobic codigestion of sewage sludge and grease waste (GW) doubles methane yield. • High GW doses in the influent leads to instability and LCFA accumulation in the effluent. • GW addition promotes acetoclastic activity whilst worsening the hydrogenothrophic activity. • The mesophilic codigestion with GW performs better than the thermophilic one. - Abstract: Thermophilic co-digestion of sewage sludge with three different doses of trapped grease waste (GW) from the pre-treatment of a WWTP has been assessed in a CSTR bench-scale reactor. After adding 12% and 27% of grease waste (on COD basis), the organic loading rate increased from 2.2 to 2.3 and 2.8 kgCOD m−3 d−1 respectively, and the methane yield increased 1.2 and 2.2 times. Further GW increase (37% on COD basis) resulted in an unstable methane yield and in long chain fatty acids (LCFA) accumulation. Although this inestability, the presence of volatile fatty acids in the effluent was negligible, showing good adaptation to fats of the thermophilic biomass. Nevertheless, the presence of LCFA in the effluent worsens its dewatering properties. Specific methanogenic activity tests showed that the addition of grease waste ameliorates the acetoclastic activity in detriment of the hydrogenotrophic activity, and suggests that the tolerance to LCFA can be further enhanced by slowly increasing the addition of lipid-rich materials

  10. Readily Available Sources of Long-Chain Omega-3 Oils: Is Farmed Australian Seafood a Better Source of the Good Oil than Wild-Caught Seafood?

    Directory of Open Access Journals (Sweden)

    Peter D. Nichols

    2014-03-01

    Full Text Available Seafood consumption enhances intake of omega-3 long-chain (≥C20 polyunsaturated fatty acids (termed LC omega-3 oils. Humans biosynthesize only small amounts of LC-omega-3, so they are considered semi-essential nutrients in our diet. Concern has been raised that farmed fish now contain lower LC omega-3 content than wild-harvested seafood due to the use of oil blending in diets fed to farmed fish. However, we observed that two major Australian farmed finfish species, Atlantic salmon (Salmo salar and barramundi (Lates calcifer, have higher oil and LC omega-3 content than the same or other species from the wild, and remain an excellent means to achieve substantial intake of LC omega-3 oils. Notwithstanding, LC omega-3 oil content has decreased in these two farmed species, due largely to replacing dietary fish oil with poultry oil. For Atlantic salmon, LC omega-3 content decreased ~30%–50% between 2002 and 2013, and the omega-3/omega-6 ratio also decreased (>5:1 to <1:1. Australian consumers increasingly seek their LC omega-3 from supplements, therefore a range of supplement products were compared. The development and future application of oilseeds containing LC omega-3 oils and their incorporation in aquafeeds would allow these health-benefitting oils to be maximized in farmed Australian seafood. Such advances can assist with preventative health care, fisheries management, aquaculture nutrition, an innovative feed/food industry and ultimately towards improved consumer health.

  11. Readily available sources of long-chain omega-3 oils: is farmed Australian seafood a better source of the good oil than wild-caught seafood?

    Science.gov (United States)

    Nichols, Peter D; Glencross, Brett; Petrie, James R; Singh, Surinder P

    2014-01-01

    Seafood consumption enhances intake of omega-3 long-chain (≥C₂₀) polyunsaturated fatty acids (termed LC omega-3 oils). Humans biosynthesize only small amounts of LC-omega-3, so they are considered semi-essential nutrients in our diet. Concern has been raised that farmed fish now contain lower LC omega-3 content than wild-harvested seafood due to the use of oil blending in diets fed to farmed fish. However, we observed that two major Australian farmed finfish species, Atlantic salmon (Salmo salar) and barramundi (Lates calcifer), have higher oil and LC omega-3 content than the same or other species from the wild, and remain an excellent means to achieve substantial intake of LC omega-3 oils. Notwithstanding, LC omega-3 oil content has decreased in these two farmed species, due largely to replacing dietary fish oil with poultry oil. For Atlantic salmon, LC omega-3 content decreased ~30%-50% between 2002 and 2013, and the omega-3/omega-6 ratio also decreased (>5:1 to oils and their incorporation in aquafeeds would allow these health-benefitting oils to be maximized in farmed Australian seafood. Such advances can assist with preventative health care, fisheries management, aquaculture nutrition, an innovative feed/food industry and ultimately towards improved consumer health. PMID:24618601

  12. Excess molar enthalpies of binary mixtures containing 2-decanone or dipentyl ether with long-chain n-alkanes at T = 298.15 K

    International Nuclear Information System (INIS)

    Research highlights: → An isothermal titration calorimeter was used for enthalpy data measurment. → The investigated systems are 2-decanone or dipentyl ether with long-chain n-alkanes. → The excess enthalpies are all positive over entire composition range. → The Patel-Teja equation of state with two parameters gives the best representation. - Abstract: Excess molar enthalpies (HE) of binary mixtures of 2-decanone or dipentyl ether with n-alkanes, including n-dodecane, n-tetradecane, and n-hexadecane, were measured with an isothermal titration calorimeter (ITC) at T = 298.15 K under atmospheric pressure. All the measured HE values are positive over the entire range of composition, indicating that all these mixing processes are endothermic. The HE values varying with composition are found to be nearly symmetric for each binary system. It was also shown that the HE values follow the order of n-hexadecane > n-tetradecane > n-dodecane at a given composition in either the 2-decanone or dipentyl ether binary systems. An empirical Redlich-Kister equation correlated quantitatively these new HE data. The Peng-Robinson and the Patel-Teja equations of state, and the NRTL model were also applied to fit the HE results. Among these tested correlative models, the Patel-Teja equation of state with two adjustable binary interaction parameters generally yielded the best representation.

  13. Long chain polyunsaturated fatty acid supplementation in infancy increases length- and weight-for-age but not BMI to 6 years when controlling for effects of maternal smoking.

    Science.gov (United States)

    Currie, L M; Tolley, E A; Thodosoff, J M; Kerling, E H; Sullivan, D K; Colombo, J; Carlson, S E

    2015-07-01

    Long chain polyunsaturated fatty acids (LCPUFA) are added to infant formula but their effect on long-term growth of children is under studied. We evaluated the effects of feeding LCPUFA-supplemented formula (n = 54) compared to control formula (n = 15) throughout infancy on growth from birth-6 years. Growth was described using separate models developed with the MIXED procedure of SAS(®) that included maternal smoking history and gender. Compared to children fed control formula, children who consumed LCPUFA supplemented formula had higher length-/stature-/and weight-for-age percentiles but not body mass index (BMI) percentile from birth to 6 years. Maternal smoking predicted lower stature (2-6 years), higher weight-for-length (birth-18 months) and BMI percentile (2-6 years) independent of LCPUFA effects. Gender interacted with the effect of LCPUFA on stature, and the relationship between smoking and BMI, with a larger effect for boys. Energy intake did not explain growth differences. A relatively small control sample is a limitation. PMID:25936840

  14. Designing hydrophobic sheet protected Eu(III)-tetracycline complex using long chain unsaturated fatty acid: Efficient ‘antenna effect’ in aqueous medium

    International Nuclear Information System (INIS)

    We have designed a novel ternary system consisting of Tetracycline hydrochloride (TC), Eu(III) and unsaturated long chain fatty acid (Oleic acid, α-Linolenic acid) in aqueous buffer at physiological pH of 7.2. The systems exhibit highly efficient ‘antenna effect’ of Eu(III) compared to that observed in the binary system of TC and Eu(III) [Eu3TC]. Transients of Eu(III) emission in aqueous buffer and D2O buffer show that the number of water molecules, coordinated directly to the Eu(III) ion, decreases from 12 in Eu3TC to 2 in the ternary system using oleic acid. The micelle formed by the bent conformation of the unsaturated oleic acid provides a hydrophobic sheet on all sides of Eu3TC complex protecting Eu(III) from interacting with O–H oscillator. The simple biocompatible system could be used for imaging purpose, and biomedical assay. - Highlights: • A ternary system containing a ligand, oleic acid and Eu(III) has been developed. • The system exhibits enhanced ‘antenna effect’ in aqueous medium at pH=7.2. • This may help design a useful biosensor/imaging technique using Eu(III)

  15. Designing hydrophobic sheet protected Eu(III)-tetracycline complex using long chain unsaturated fatty acid: Efficient ‘antenna effect’ in aqueous medium

    Energy Technology Data Exchange (ETDEWEB)

    Samanta, Swarna Kamal; Sanyal, Sagarika; Samanta, Sugata; Ghosh, Sanjib, E-mail: pchemsg@gmail.com

    2015-04-15

    We have designed a novel ternary system consisting of Tetracycline hydrochloride (TC), Eu(III) and unsaturated long chain fatty acid (Oleic acid, α-Linolenic acid) in aqueous buffer at physiological pH of 7.2. The systems exhibit highly efficient ‘antenna effect’ of Eu(III) compared to that observed in the binary system of TC and Eu(III) [Eu{sub 3}TC]. Transients of Eu(III) emission in aqueous buffer and D{sub 2}O buffer show that the number of water molecules, coordinated directly to the Eu(III) ion, decreases from 12 in Eu{sub 3}TC to 2 in the ternary system using oleic acid. The micelle formed by the bent conformation of the unsaturated oleic acid provides a hydrophobic sheet on all sides of Eu{sub 3}TC complex protecting Eu(III) from interacting with O–H oscillator. The simple biocompatible system could be used for imaging purpose, and biomedical assay. - Highlights: • A ternary system containing a ligand, oleic acid and Eu(III) has been developed. • The system exhibits enhanced ‘antenna effect’ in aqueous medium at pH=7.2. • This may help design a useful biosensor/imaging technique using Eu(III)

  16. DHA-Containing Oilseed: A Timely Solution for the Sustainability Issues Surrounding Fish Oil Sources of the Health-Benefitting Long-Chain Omega-3 Oils

    Directory of Open Access Journals (Sweden)

    Soressa M. Kitessa

    2014-05-01

    Full Text Available Benefits of long-chain (≥C20 omega-3 oils (LC omega-3 oils for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA; optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3. However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA.

  17. Changes in cholesterol homeostasis modify the response of F1B hamsters to dietary very long chain n-3 and n-6 polyunsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    Rader Daniel J

    2011-10-01

    Full Text Available Abstract Background The plasma lipoprotein response of F1B Golden-Syrian hamsters fed diets high in very long chain (VLC n-3 polyunsaturated fatty acids (PUFA is paradoxical to that observed in humans. This anomaly is attributed, in part, to low lipoprotein lipase activity and is dependent on cholesterol status. To further elucidate the mechanism(s for these responses, hamsters were fed diets containing supplemental fish oil (VLC n-3 PUFA or safflower oil (n-6 PUFA (both 10% [w/w] and either cholesterol-supplemented (0.1% cholesterol [w/w] or cholesterol-depleted (0.01% cholesterol [w/w] and 10 days prior to killing fed 0.15% lovastatin+2% cholestyramine [w/w]. Results Cholesterol-supplemented hamsters fed fish oil, relative to safflower oil, had higher non-high density lipoprotein (HDL cholesterol and triglyceride concentrations (P Conclusion These data suggest disturbing cholesterol homeostasis in F1B hamsters alters their response to dietary fatty acids, which is reflected in altered plasma lipoprotein patterns and regulation of genes associated with their metabolism.

  18. DHA-containing oilseed: a timely solution for the sustainability issues surrounding fish oil sources of the health-benefitting long-chain omega-3 oils.

    Science.gov (United States)

    Kitessa, Soressa M; Abeywardena, Mahinda; Wijesundera, Chakra; Nichols, Peter D

    2014-05-01

    Benefits of long-chain (≥C20) omega-3 oils (LC omega-3 oils) for reduction of the risk of a range of disorders are well documented. The benefits result from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); optimal intake levels of these bioactive fatty acids for maintenance of normal health and prevention of diseases have been developed and adopted by national and international health agencies and science bodies. These developments have led to increased consumer demand for LC omega-3 oils and, coupled with increasing global population, will impact on future sustainable supply of fish. Seafood supply from aquaculture has risen over the past decades and it relies on harvest of wild catch fisheries also for its fish oil needs. Alternate sources of LC omega-3 oils are being pursued, including genetically modified soybean rich in shorter-chain stearidonic acid (SDA, 18:4ω3). However, neither oils from traditional oilseeds such as linseed, nor the SDA soybean oil have shown efficient conversion to DHA. A recent breakthrough has seen the demonstration of a land plant-based oil enriched in DHA, and with omega-6 PUFA levels close to that occurring in marine sources of EPA and DHA. We review alternative sources of DHA supply with emphasis on the need for land plant oils containing EPA and DHA. PMID:24858407

  19. Long-chain fatty acids regulate liver carnitine palmitoyltransferase I gene (L-CPT I) expression through a peroxisome-proliferator-activated receptor alpha (PPARalpha)-independent pathway.

    Science.gov (United States)

    Louet, J F; Chatelain, F; Decaux, J F; Park, E A; Kohl, C; Pineau, T; Girard, J; Pegorier, J P

    2001-01-01

    Liver carnitine palmitoyltransferase I (L-CPT I) catalyses the transfer of long-chain fatty acid (LCFA) for translocation across the mitochondrial membrane. Expression of the L-CPT I gene is induced by LCFAs as well as by lipid-lowering compounds such as clofibrate. Previous studies have suggested that the peroxisome-proliferator-activated receptor alpha (PPARalpha) is a common mediator of the transcriptional effects of LCFA and clofibrate. We found that free LCFAs rather than acyl-CoA esters are the signal metabolites responsible for the stimulation of L-CPT I gene expression. Using primary culture of hepatocytes we found that LCFAs failed to stimulate L-CPT I gene expression both in wild-type and PPARalpha-null mice. These results suggest that the PPARalpha-knockout mouse does not represent a suitable model for the regulation of L-CPT I gene expression by LCFAs in the liver. Finally, we determined that clofibrate stimulates L-CPT I through a classical direct repeat 1 (DR1) motif in the promoter of the L-CPT I gene while LCFAs induce L-CPT I via elements in the first intron of the gene. Our results demonstrate that LCFAs can regulate gene expression through PPARalpha-independent pathways and suggest that the regulation of gene expression by dietary lipids is more complex than previously proposed. PMID:11171094

  20. SIRT3 and SIRT5 regulate the enzyme activity and cardiolipin binding of very long-chain acyl-CoA dehydrogenase.

    Directory of Open Access Journals (Sweden)

    Yuxun Zhang

    Full Text Available SIRT3 and SIRT5 have been shown to regulate mitochondrial fatty acid oxidation but the molecular mechanisms behind the regulation are lacking. Here, we demonstrate that SIRT3 and SIRT5 both target human very long-chain acyl-CoA dehydrogenase (VLCAD, a key fatty acid oxidation enzyme. SIRT3 deacetylates and SIRT5 desuccinylates K299 which serves to stabilize the essential FAD cofactor in the active site. Further, we show that VLCAD binds strongly to cardiolipin and isolated mitochondrial membranes via a domain near the C-terminus containing lysines K482, K492, and K507. Acetylation or succinylation of these residues eliminates binding of VLCAD to cardiolipin. SIRT3 deacetylates K507 while SIRT5 desuccinylates K482, K492, and K507. Sirtuin deacylation of recombinant VLCAD rescues membrane binding. Endogenous VLCAD from SIRT3 and SIRT5 knockout mouse liver shows reduced binding to cardiolipin. Thus, SIRT3 and SIRT5 promote fatty acid oxidation by converging upon VLCAD to promote its activity and membrane localization. Regulation of cardiolipin binding by reversible lysine acylation is a novel mechanism that is predicted to extrapolate to other metabolic proteins that localize to the inner mitochondrial membrane.

  1. The metabolic syndrome of fructose-fed rats: effects of long-chain polyunsaturated ω3 and ω6 fatty acids. VII. Oxidative stress.

    Science.gov (United States)

    Mellouk, Zoheir; Sener, Abdullah; Ait Yahia, Dalila; Malaisse, Willy J

    2012-12-01

    In the present study, the plasma concentration, and liver, heart, kidney, soleus muscle and visceral adipose tissue content of thiobarbituric acid reactive substrates (TBARS), carbonyl radicals, hydroperoxides and nitric oxide were measured in control rats exposed for 8 weeks to a diet containing 64% (w/w) starch and 5% sunflower oil and in animals fed a diet containing 64% D-fructose and 5% sunflower oil or 3.4% sunflower oil mixed with 1.6% safflower or salmon oil. Coherent measurements of the plasma concentrations or tissue contents of these metabolites revealed increases in TBARS, carbonyl radical and hydroperoxide levels and a decrease in nitric oxide levels in the 5% sunflower oil-fed rats. In the fructose-fed rats, the partial substitution of sunflower oil by either safflower or salmon oil minimized the changes. These findings provide further evidence in support of the favorable effects of the dietary supply of long-chain polyunsaturated ω6 and ω3 fatty acids upon the metabolic disturbances prevailing in the fructose-induced metabolic syndrome. PMID:23007226

  2. Diversity of long-chain toxins in Tityus zulianus and Tityus discrepans venoms (Scorpiones, Buthidae): molecular, immunological, and mass spectral analyses.

    Science.gov (United States)

    Borges, Adolfo; García, Carmen C; Lugo, Elizabeth; Alfonzo, Marcelo J; Jowers, Michael J; Op den Camp, Huub J M

    2006-01-01

    In Venezuela, stings by Tityus zulianus scorpions produce cardiorespiratory arrest, whereas envenoming by Tityus discrepans involves gastrointestinal/pancreatic complications, suggesting structural and/or functional differences. We sought to compare their toxin repertoires through immunological, molecular, and mass spectral analyses. First, in vivo tests showed that neutralization of T. zulianus venom toxicity by the anti-T. discrepans antivenom was not complete. To compare T. discrepans and T. zulianus long-chain (sodium channel-active) toxins, their most toxic Sephadex G-50 fractions, TdII and TzII, were subjected to acid-urea PAGE, which showed differences in composition. Amplification of toxin-encoding mRNAs using a leader peptide-based oligonucleotide rendered cDNAs representing twelve T. discrepans and two T. zulianus distinct toxin transcripts, including only one shared component, indicating divergence between T. zulianus and T. discrepans 5' region-encoded, toxin signal peptides. A 3'-UTR polymorphism was also noticed among the transcripts encoding shared components Tz1 and Td4. MALDI-TOF MS profiling of TdII and TzII produced species-specific spectra, with seven of the individual masses matching those predicted by cDNA sequencing. Phylogenetic analysis showed that the unique T. zulianus transcript-encoded sequence, Tz2, is structurally related to Tityus serrulatus and Centruroides toxins. Together with previous reports, this work indicates that T. zulianus and T. discrepans toxin repertoires differ structurally and functionally. PMID:16356783

  3. CPT1α over-expression increases long-chain fatty acid oxidation and reduces cell viability with incremental palmitic acid concentration in 293T cells

    International Nuclear Information System (INIS)

    To test the cellular response to an increased fatty acid oxidation, we generated a vector for an inducible expression of the rate-limiting enzyme carnitine palmitoyl-transferase 1α (CPT1α). Human embryonic 293T kidney cells were transiently transfected and expression of the CPT1α transgene in the tet-on vector was activated with doxycycline. Fatty acid oxidation was measured by determining the conversion of supplemented, synthetic cis-10-heptadecenoic acid (C17:1n-7) to C15:ln-7. CPT1α over-expression increased mitochondrial long-chain fatty acid oxidation about 6-fold. Addition of palmitic acid (PA) decreased viability of CPT1α over-expressing cells in a concentration-dependent manner. Both, PA and CPT1α over-expression increased cell death. Interestingly, PA reduced total cell number only in cells over-expressing CPT1α, suggesting an effect on cell proliferation that requires PA translocation across the mitochondrial inner membrane. This inducible expression system should be well suited to study the roles of CPT1 and fatty acid oxidation in lipotoxicity and metabolism in vivo

  4. The effect of a controlled manipulation of maternal dietary fat intake on medium and long chain fatty acids in human breast milk in Saskatoon, Canada

    Directory of Open Access Journals (Sweden)

    Stephen Alison M

    2010-02-01

    Full Text Available Abstract Background Few studies in recent years have demonstrated the effect of maternal diet on fatty acid composition of human milk. Methods Fourteen free-living lactating women participated in a cross-over dietary intervention study, consuming a low fat diet (17.6% of energy as fat, 14.4% of energy as protein, 68.0% of energy as carbohydrate and a high fat diet (40.3% of energy as fat, 14.4% of energy as protein, 45.3% of energy as carbohydrate each for periods of 4 days, in randomised order. Each mother was her own control. Mature milk samples were collected during each period and analysed for medium and long chain fatty acids. Results The concentration of medium chain fatty acids (MCFA, was 13.6% in breast milk for the low fat diet compared to 11.4% for the high fat (p Conclusions Changing maternal dietary fat intake has a rapid response in terms of changes to fatty acids in breast milk.

  5. Long-Chain Omega-3 Polyunsaturated Fatty Acids Have Developmental Effects on the Crop Pest, the Cabbage White Butterfly Pieris rapae.

    Science.gov (United States)

    Hixson, Stefanie M; Shukla, Kruti; Campbell, Lesley G; Hallett, Rebecca H; Smith, Sandy M; Packer, Laurence; Arts, Michael T

    2016-01-01

    Nutritional enhancement of crops using genetic engineering can potentially affect herbivorous pests. Recently, oilseed crops have been genetically engineered to produce the long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) at levels similar to that found in fish oil; to provide a more sustainable source of these compounds than is currently available from wild fish capture. We examined some of the growth and development impacts of adding EPA and DHA to an artificial diet of Pieris rapae, a common pest of Brassicaceae plants. We replaced 1% canola oil with EPA: DHA (11:7 ratio) in larval diets, and examined morphological traits and growth of larvae and ensuing adults across 5 dietary treatments. Diets containing increasing amounts of EPA and DHA did not affect developmental phenology, larval or pupal weight, food consumption, nor larval mortality. However, the addition of EPA and DHA in larval diets resulted in progressively heavier adults (F 4, 108 = 6.78; p = 0.011), with smaller wings (p < 0.05) and a higher frequency of wing deformities (R = 0.988; p = 0.001). We conclude that the presence of EPA and DHA in diets of larval P. rapae may alter adult mass and wing morphology; therefore, further research on the environmental impacts of EPA and DHA production on terrestrial biota is advisable. PMID:27011315

  6. Novel long chain fatty acid derivatives of quercetin-3-O-glucoside reduce cytotoxicity induced by cigarette smoke toxicants in human fetal lung fibroblasts.

    Science.gov (United States)

    Warnakulasuriya, Sumudu N; Ziaullah; Rupasinghe, H P Vasantha

    2016-06-15

    Smoking has become a global health concern due to its association with many disease conditions, such as chronic obstructive pulmonary disease (COPD), cardiovascular diseases (CVD) and cancer. Flavonoids are plant polyphenolic compounds, studied extensively for their antioxidant, anti-inflammatory, and anti-carcinogenic properties. Quercetin-3-O-glucoside (Q3G) is a flavonoid which is widely found in plants. Six novel long chain fatty acid [stearic acid, oleic acid, linoleic acid, α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)] derivatives of Q3G were evaluated for their potential in protecting human lung fibroblasts against cytotoxicity induced by selected cigarette smoke toxicants: 4-(methylnitrosoamino)-1-(3-pyridinyl)-1-butanone (NNK), benzo-α-pyrene (BaP), nicotine and chromium (Cr[VI]). Nicotine and Cr[VI] induced toxicity in fibroblasts and reduced the percentage of viable cells, while BaP and NNK did not affect cell viability. The fatty acid derivatives of Q3G provided protection against nicotine- and Cr[VI]-induced cell death and membrane lipid peroxidation. Based on the evaluation of inflammatory markers of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2), the fatty acid derivatives of Q3G were found to be effective in lowering the inflammatory response. Overall, these novel fatty acid esters of Q3G warrant further investigation as potential cytoprotective agents. PMID:27071958

  7. MRI study of the cuprizone-induced mouse model of multiple sclerosis: demyelination is not found after co-treatment with polyprenols (long-chain isoprenoid alcohols)

    Science.gov (United States)

    Khodanovich, M.; Glazacheva, V.; Pan, E.; Akulov, A.; Krutenkova, E.; Trusov, V.; Yarnykh, V.

    2016-02-01

    Multiple sclerosis is a neurological disorder with poorly understood pathogenic mechanisms and a lack of effective therapies. Therefore, the search for new MS treatments remains very important. This study was performed on a commonly used cuprizone animal model of multiple sclerosis. It evaluated the effect of a plant-derived substance called Ropren® (containing approximately 95% polyprenols or long-chain isoprenoid alcohols) on cuprizone- induced demyelination. The study was performed on 27 eight-week old male CD-1 mice. To induce demyelination mice were fed 0.5% cuprizone in the standard diet for 10 weeks. Ropren® was administered in one daily intraperitoneal injection (12mg/kg), beginning on the 6th week of the experiment. On the 11th week, the corpus callosum in the brain was evaluated in all animals using magnetic resonance imaging with an 11.7 T animal scanner using T2- weighted sequence. Cuprizone treatment successfully induced the model of demyelination with a significant decrease in the size of the corpus callosum compared with the control group (p<0.01). Mice treated with both cuprizone and Ropren® did not exhibit demyelination in the corpus callosum (p<0.01). This shows the positive effect of polyprenols on cuprizone-induced demyelination in mice.

  8. An alternative pathway for the effective production of the omega-3 long-chain polyunsaturates EPA and ETA in transgenic oilseeds.

    Science.gov (United States)

    Ruiz-Lopez, Noemi; Haslam, Richard P; Usher, Sarah; Napier, Johnathan A; Sayanova, Olga

    2015-12-01

    The synthesis and accumulation of omega-3 long-chain polyunsaturated fatty acids in transgenic Camelina sativa is demonstrated using the so-called alternative pathway. This aerobic pathway is found in a small number of taxonomically unrelated unicellular organisms and utilizes a C18 Δ9-elongase to generate C20 PUFAs. Here, we evaluated four different combinations of seed-specific transgene-derived activities to systematically determine the potential of this pathway to direct the synthesis of eicosapentaenoic acid (EPA) in transgenic plants. The accumulation of EPA and the related omega-3 LC-PUFA eicosatetraenoic acid (ETA) was observed up to 26.4% of total seed fatty acids, of which ETA was 9.5%. Seed oils such as these not only represent an additional source of EPA, but also an entirely new source of the bona fide fish oil ETA. Detailed lipidomic analysis of the alternative pathway in Camelina revealed that the acyl-substrate preferences of the different activities in the pathway can still generate a substrate-dichotomy bottleneck, largely due to inefficient acyl-exchange from phospholipids into the acyl-CoA pool. However, significant levels of EPA and ETA were detected in the triacylglycerols of transgenic seeds, confirming the channelling of these fatty acids into this storage lipid. PMID:25640865

  9. Successful high-level accumulation of fish oil omega-3 long-chain polyunsaturated fatty acids in a transgenic oilseed crop.

    Science.gov (United States)

    Ruiz-Lopez, Noemi; Haslam, Richard P; Napier, Johnathan A; Sayanova, Olga

    2014-01-01

    Omega-3 (also called n-3) long-chain polyunsaturated fatty acids (≥C20; LC-PUFAs) are of considerable interest, based on clear evidence of dietary health benefits and the concurrent decline of global sources (fish oils). Generating alternative transgenic plant sources of omega-3 LC-PUFAs, i.e. eicosapentaenoic acid (20:5 n-3, EPA) and docosahexaenoic acid (22:6 n-3, DHA) has previously proved problematic. Here we describe a set of heterologous genes capable of efficiently directing synthesis of these fatty acids in the seed oil of the crop Camelina sativa, while simultaneously avoiding accumulation of undesirable intermediate fatty acids. We describe two iterations: RRes_EPA in which seeds contain EPA levels of up to 31% (mean 24%), and RRes_DHA, in which seeds accumulate up to 12% EPA and 14% DHA (mean 11% EPA and 8% DHA). These omega-3 LC-PUFA levels are equivalent to those in fish oils, and represent a sustainable, terrestrial source of these fatty acids. We also describe the distribution of these non-native fatty acids within C. sativa seed lipids, and consider these data in the context of our current understanding of acyl exchange during seed oil synthesis. PMID:24308505

  10. Cloning and characterization of human very-long-chain acyl-CoA dehydrogenase cDNA, chromosomal assignment of the gene and identification in four patients of nine different mutations within the VLCAD gene

    DEFF Research Database (Denmark)

    Andresen, B S; Bross, P; Vianey-Saban, C; Divry, P; Zabot, M T; Roe, C R; Nada, M A; Byskov, A; Kruse, T A; Neve, S; Kristiansen, K; Knudsen, I; Corydon, M J; Gregersen, N

    1996-01-01

    Very-long-chain acyl-CoA dehydrogenase (VLCAD) is one of four straight-chain acyl-CoA dehydrogenase (ACD) enzymes, which are all nuclear encoded mitochondrial flavoproteins catalyzing the initial step in fatty acid beta-oxidation. We have used the very fast, Rapid Amplification of cDNA Ends (RACE...

  11. ERYTHROCYTE AND PLASMA-CHOLESTEROL ESTER LONG-CHAIN POLYUNSATURATED FATTY-ACIDS OF LOW-BIRTH-WEIGHT BABIES FED PRETERM FORMULA WITH AND WITHOUT RIBONUCLEOTIDES - COMPARISON WITH HUMAN-MILK

    NARCIS (Netherlands)

    WOLTIL, HA; VANBEUSEKOM, CM; SIEMENSMA, AD; POLMAN, HA; MUSKIET, FAJ; OKKEN, A

    1995-01-01

    We investigated whether a regular formula for premature infants (pre) supplemented with ribonucleotides (pre+RN) raises erythrocyte and plasma cholesterol ester (CE) long-chain polyunsaturated fatty acids (LCPUFAs) of low-birthweight babies (less than or equal to 2.50 kg) compared with their breast-

  12. Higher de novo synthesized fatty acids and lower omega 3-and omega 6-long-chain polyunsaturated fatty acids in umbilical vessels of women with preeclampsia and high fish intakes

    NARCIS (Netherlands)

    Huiskes, Victor J. B.; Kuipers, Remko S.; Velzing-Aarts, Francien V.; Dijck-Brouwer, D. A. Janneke; van der Meulen, Jan; Muskiet, Frits A. J.

    2009-01-01

    Umbilical veins (UV) and arteries (UA) of preeclamptic women in Curacao harbor lower long-chain polyunsaturated fatty acids (LCP). The present aim was to test these findings in Mwanza (Tanzania), whose inhabitants have high LCP omega 3 and LCP omega 6 intakes from Lake Victoria fish. Women with pree

  13. Ultra-bright alkylated graphene quantum dots

    Science.gov (United States)

    Feng, Lan; Tang, Xing-Yan; Zhong, Yun-Xin; Liu, Yue-Wen; Song, Xue-Huan; Deng, Shun-Liu; Xie, Su-Yuan; Yan, Jia-Wei; Zheng, Lan-Sun

    2014-10-01

    Highly efficient and stable photoluminescence (PL) are urgently desired for graphene quantum dots (GQDs) to facilitate their prospective applications as optical materials. Here, we report the facile and straightforward synthesis of alkylated graphene quantum dots (AGQDs) via the solvothermal reaction of propagatively alkylated graphene sheets (PAGenes). In contrast to most GQDs reported so far, the synthesized AGQDs process pH-independent and ultra-bright PL with a relative quantum yield of up to 65%. Structural and chemical composition characterization demonstrated that the synthesized AGQDs are nearly oxygen-defect-free with alkyl groups decorated on edges and basal plane, which may contribute to their greatly improved pH tolerance and high quantum efficiency. The photocatalytic performance of AGQDs-P25 nanocomposites was evaluated by the degradation of Rhodamine B under visible light. The photocatalytic rate is ca. 5.9 times higher than that of pure P25, indicating that AGQDs could harness the visible spectrum of sunlight for energy conversion or environmental therapy.Highly efficient and stable photoluminescence (PL) are urgently desired for graphene quantum dots (GQDs) to facilitate their prospective applications as optical materials. Here, we report the facile and straightforward synthesis of alkylated graphene quantum dots (AGQDs) via the solvothermal reaction of propagatively alkylated graphene sheets (PAGenes). In contrast to most GQDs reported so far, the synthesized AGQDs process pH-independent and ultra-bright PL with a relative quantum yield of up to 65%. Structural and chemical composition characterization demonstrated that the synthesized AGQDs are nearly oxygen-defect-free with alkyl groups decorated on edges and basal plane, which may contribute to their greatly improved pH tolerance and high quantum efficiency. The photocatalytic performance of AGQDs-P25 nanocomposites was evaluated by the degradation of Rhodamine B under visible light. The

  14. Concentrations of long-chain acyl-acyl carrier proteins during fatty acid synthesis by chloroplasts isolated from pea (Pisum sativum), safflower (Carthamus tinctoris), and amaranthus (Amaranthus lividus) leaves

    International Nuclear Information System (INIS)

    Fatty acid synthesis from [1-14C]acetate by chloroplasts isolated from peas and amaranthus was linear for at least 15 min, whereas incorporation of the tracer into long-chain acyl-acyl carrier protein (ACP) did not increase after 2-3 min. When reactions were transferred to the dark after 3-5 min, long-chain acyl-ACPs lost about 90% of their radioactivity and total fatty acids retained all of theirs. Half-lives of the long-chain acyl-ACPs were estimated to be 10-15 s. Concentrations of palmitoyl-, stearoyl-, and oleoyl-ACP as indicated by equilibrium labeling during steady-state fatty acid synthesis, ranged from 0.6-1.1, 0.2-0.7, and 0.4-1.6 microM, respectively, for peas and from 1.6-1.9, 1.3-2.6, and 0.6-1.4 microM, respectively, for amaranthus. These values are based on a chloroplast volume of 47 microliters/mg chlorophyll and varied according to the mode of the incubation. A slow increase in activity of the fatty acid synthetase in safflower chloroplasts resulted in long-chain acyl-ACPs continuing to incorporate labeled acetate for 10 min. Upon re-illumination following a dark break, however, both fatty acid synthetase activity and acyl-ACP concentrations increased very rapidly. Palmitoyl-ACP was present at concentrations up to 2.5 microM in safflower chloroplasts, whereas those of stearoyl- and oleoyl-ACPs were in the lower ranges measured for peas. Acyl-ACPs were routinely separated from extracts of chloroplasts that had been synthesising long-chain fatty acids from labeled acetate by a minor modification of the method of Mancha et al. The results compared favorably with those obtained using alternative analytical methods such as adsorption to filter paper and partition chromatography on silicic acid columns

  15. Alkyl- and fluoroalkyltrialkoxysilanes for wettability modification

    Energy Technology Data Exchange (ETDEWEB)

    Dopierala, Katarzyna, E-mail: katarzyna.dopierala@put.poznan.pl [Institute of Chemical Technology and Engineering, Poznan University of Technology, Pl. Marii Skłodowskiej-Curie 2, Poznań 60-965 (Poland); Maciejewski, Hieronim [Poznań Science and Technology Park, Rubież 46, Poznań 61-612 (Poland); Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, Poznań 60-780 (Poland); Karasiewicz, Joanna [Poznań Science and Technology Park, Rubież 46, Poznań 61-612 (Poland); Prochaska, Krystyna [Institute of Chemical Technology and Engineering, Poznan University of Technology, Pl. Marii Skłodowskiej-Curie 2, Poznań 60-965 (Poland)

    2013-10-15

    Alkyl- and fluoroalkyltriethoxysilanes were investigated as potential surface modifiers. Many aspects concerning trialkoxysilanes were discussed, starting from hydrolysis of silanes in water solutions, the effect of this hydrolysis on the surface tension, wettability of the modified surface to the morphology of the modified surface. Surface tension and contact angle measurements as well as scanning electron microscopy were used to characterise alkyl- and fluoroalkyltriethoxysilanes and their ability to modify the wettability of glass. The effect of such modification was superhydrophobic surface with high values of contact angles. Superhydrophobic behaviour was observed as a result of two-step modification providing increased surface roughness thanks to the use of different size silica particles and surface chemical modification with fluorosilane molecules.

  16. Teddy Bear Stories

    DEFF Research Database (Denmark)

    van Leeuwen, Theo; Caldas-Coulthardt, Carmen

    2014-01-01

    This paper presents a semiotic analysis of a key cultural artefact, the teddy bear. After introducing the iconography of the teddy bear, it analyses different kinds of stories to show how teddy bears are endowed with meaning in everyday life: stories from children's books, reminiscenses by adults...

  17. N-3 long-chain polyunsaturated fatty acids and risk of all-cause mortality among general populations: a meta-analysis.

    Science.gov (United States)

    Chen, Guo-Chong; Yang, Jing; Eggersdorfer, Manfred; Zhang, Weiguo; Qin, Li-Qiang

    2016-01-01

    Prospective observational studies have shown inconsistent associations of dietary or circulating n-3 long-chain polyunsaturated fatty acids (LCPUFA) with risk of all-cause mortality. A meta-analysis was performed to evaluate the associations. Potentially eligible studies were identified by searching PubMed and EMBASE databases. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated using the random-effects model. Eleven prospective studies involving 371 965 participants from general populations and 31 185 death events were included. The summary RR of all-cause mortality for high-versus-low n-3 LCPUFA intake was 0.91 (95% CI: 0.84-0.98). The summary RR for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake was 0.83 (95% CI: 0.75-0.92) and 0.81 (95% CI: 0.74-0.95), respectively. In the dose-response analysis, each 0.3 g/d increment in n-3 LCPUFA intake was associated with 6% lower risk of all-cause mortality (RR = 0.94, 95% CI: 0.89-0.99); and each 1% increment in the proportions of circulating EPA and DHA in total fatty acids in blood was associated with 20% (RR = 0.80, 95% CI: 0.65-0.98) and 21% (RR = 0.79, 95% CI: 0.63-0.99) decreased risk of all-cause mortality, respectively. Moderate to high heterogeneity was observed across our anlayses. Our findings suggest that both dietary and circulating LCPUFA are inversely associated with all-cause mortality. PMID:27306836

  18. The effect of n-3 long chain fatty acids supplementation on plasma peroxisome proliferator activated receptor gamma and thyroid hormones in obesity

    Directory of Open Access Journals (Sweden)

    Parizad Taraghijou

    2012-01-01

    Full Text Available Background: Peroxisome proliferator-activated receptor gamma (PPAR γ is a transcription factor, which is abundantly expressed in adipose tissue and has a direct link to adiposity. It seems that long-chain polyunsaturated fatty acids (LC-PUFAs can regulate PPAR γ expression. The purpose of this study was to investigate the effects of n-3LC PUFA supplementation on plasma levels of PPAR γ and thyroid hormones in obesity. Materials and Methods: In a randomized double-blind controlled trial, 66 subjects with obesity were assigned to 2 groups. Participants in intervention group consumed omega3 capsules contained 1000 mg n-3 fatty acids (180 mg of eicosapentaenoic acid [EPA] and 120 mg of docosahexaenoic acid [DHA] and placebo group consumed placebo capsules contained paraffin twice a day for 4 wk. Fasting blood samples and weight measurements were collected at the baseline and at the end of the trial. Plasma PPAR γ and thyroid hormones were measured by ELISA. Data were analyzed using a repeated measure model-two factor for comparing two groups in two times. Results: No significant changes were observed in PPAR γ levels between and within the groups after supplementation (P>0.05. N-3LC PUFA supplementation significantly increased T4 levels after 4 wk (P<0.05 but T3 and TSH did not change significantly. Conclusion: Our study showed that n-3LC PUFAs supplementation increased T4 levels. However, no significant changes in T3, TSH and PPAR γ plasma levels were observed in obese adults.

  19. Carbon-13 natural abundance signatures of long-chain fatty acids to determinate sediment origin: A case study in northeast Austria

    Science.gov (United States)

    Mabit, Lionel; Gibbs, Max; Meusburger, Katrin; Toloza, Arsenio; Resch, Christian; Klik, Andreas; Swales, Andrew; Alewell, Christine

    2016-04-01

    - Several recently published information from scientific research have highlighted that compound-specific stable isotope (CSSI) signatures of fatty acids (FAs) based on the measurement of carbon-13 natural abundance signatures showed great promises to identify sediment origin. The authors have used this innovative isotopic approach to investigate the sources of sediment in a three hectares Austrian sub-watershed (i.e. Mistelbach). Through a previous study using the Cs-137 technique, Mabit et al. (Geoderma, 2009) reported a local maximum sedimentation rate reaching 20 to 50 t/ha/yr in the lowest part of this watershed. However, this study did not identify the sources. Subsequently, the deposited sediment at its outlet (i.e. the sediment mixture) and representative soil samples from the four main agricultural fields - expected to be the source soils - of the site were investigated. The bulk delta carbon-13 of the samples and two long-chain FAs (i.e. C22:0 and C24:0) allowed the best statistical discrimination. Using two different mixing models (i.e. IsoSource and CSSIAR v1.00) and the organic carbon content of the soil sources and sediment mixture, the contribution of each source has been established. Results suggested that the grassed waterway contributed to at least 50% of the sediment deposited at the watershed outlet. This study, that will require further validation, highlights that CSSI and Cs-137 techniques are complementary as fingerprints and tracers for establishing land sediment redistribution and could provide meaningful information for optimized decision-making by land managers.

  20. Long chain fatty Acyl-CoA synthetase 4 is a biomarker for and mediator of hormone resistance in human breast cancer.

    Directory of Open Access Journals (Sweden)

    Xinyu Wu

    Full Text Available The purpose of this study was to determine the role of long-chain fatty acyl-CoA synthetase 4 (ACSL4 in breast cancer. Public databases were utilized to analyze the relationship between ACSL4 mRNA expression and the presence of steroid hormone and human epidermal growth factor receptor 2 (HER2 in both breast cancer cell lines and tissue samples. In addition, cell lines were utilized to assess the consequences of either increased or decreased levels of ACSL4 expression. Proliferation, migration, anchorage-independent growth and apoptosis were used as biological end points. Effects on mRNA expression and signal transduction pathways were also monitored. A meta-analysis of public gene expression databases indicated that ACSL4 expression is positively correlated with a unique subtype of triple negative breast cancer (TNBC, characterized by the absence of androgen receptor (AR and therefore referred to as quadruple negative breast cancer (QNBC. Results of experiments in breast cancer cell lines suggest that simultaneous expression of ACSL4 and a receptor is associated with hormone resistance. Forced expression of ACSL4 in ACSL4-negative, estrogen receptor α (ER-positive MCF-7 cells resulted in increased growth, invasion and anchorage independent growth, as well as a loss of dependence on estrogen that was accompanied by a reduction in the levels of steroid hormone receptors. Sensitivity to tamoxifen, triacsin C and etoposide was also attenuated. Similarly, when HER2-positive, ACSL4-negative, SKBr3 breast cancer cells were induced to express ACSL4, the proliferation rate increased and the apoptotic effect of lapatinib was reduced. The growth stimulatory effect of ACSL4 expression was also observed in vivo in nude mice when MCF-7 control and ACSL4-expressing cells were utilized to induce tumors. Our data strongly suggest that ACSL4 can serve as both a biomarker for, and mediator of, an aggressive breast cancer phenotype.

  1. Lipid remodelling during epididymal maturation of rat spermatozoa. Enrichment in plasmenylcholines containing long-chain polyenoic fatty acids of the n-9 series.

    Science.gov (United States)

    Aveldaño, M I; Rotstein, N P; Vermouth, N T

    1992-04-01

    In their transit from the caput to the cauda segments of the epididymis, rat spermatozoa undergo significant modifications in lipid content and composition. The amount of lipid phosphorus per cell decreases, and most lipid classes show specific changes in their constituent fatty acids. A depletion of phosphatidylcholine and phosphatidylethanolamine, concomitant with a virtually unchanged amount of the corresponding plasmalogens, are the major alterations, plasmenylcholine thereby becoming the major phospholipid. Diphosphatidylglycerol, sphingomyelin and the phosphoinositides decrease to a lesser extent or do not change at all, also resulting in relative increases with sperm maturation. Concerning the fatty acids, the proportions of oleate (C18:1, n-9) and linoleate (C18:2, n-6) in most lipids decrease on movement of sperm from caput to cauda, augmenting in turn the proportions of longer-chain (C20 to C24) and more unsaturated fatty acids. Docosapentaenoate (C22:5, n-6) is a major acyl chain present in all lipids at both stages, but uncommon long-chain polyenoic fatty acids of the n-9 series are also present, being almost exclusively found in the choline glycerophospholipids. These fatty acids are found to undergo the most significant changes during sperm maturation. They are minor components of plasmenylcholine in immature spermatozoa, but increase severalfold on maturation, representing more than half of the acyl chains of this major lipid in cells from the cauda. The high concentration of n-9 polyenes in mature sperm plasmenylcholine raises intriguing questions on the possible role epididymal cells may play in providing spermatozoa with such an unusual phospholipid. These plasmenylcholines could contribute to the characteristic lipid domain organization of the mature spermatozoa plasma membrane. PMID:1567371

  2. Selection for low erucic acid and genetic mapping of loci affecting the accumulation of very long-chain fatty acids in meadowfoam seed storage lipids.

    Science.gov (United States)

    Gandhi, S D; Kishore, V K; Crane, J M; Slabaugh, M B; Knapp, S J

    2009-06-01

    Erucic acid (22:1(13)) has been identified as an anti-nutritional compound in meadowfoam (Limnanthes alba) and other oilseeds in the Brassicales, a classification which has necessitated the development of low erucic acid cultivars for human consumption. The erucic acid concentrations of meadowfoam wild types (8%-24%) surpass industry standards for human consumption (long-chain fatty acids (VLCFAs) in meadowfoam seed storage lipids. LE76, a low erucic acid line, was developed by 3 cycles of selection in an ethyl methanesulfonate-treated wildtype population. LE76 produced 3% 22:1(13), threefold less than the M0 population. Wildtype x LE76 F2 populations produced continuous, approximately normal erucic and dienoic acid distributions. Loss-of-function mutations apparently did not segregate and individuals with low 22:1(13) concentrations (

  3. Characterization of mannitol-2-dehydrogenase in Saccharina japonica: evidence for a new polyol-specific long-chain dehydrogenases/reductase.

    Directory of Open Access Journals (Sweden)

    Zhanru Shao

    Full Text Available Mannitol plays a crucial role in brown algae, acting as carbon storage, organic osmolytes and antioxidant. Transcriptomic analysis of Saccharina japonica revealed that the relative genes involved in the mannitol cycle are existent. Full-length sequence of mannitol-2-dehydrogenase (M2DH gene was obtained, with one open reading frame of 2,007 bp which encodes 668 amino acids. Cis-regulatory elements for response to methyl jasmonic acid, light and drought existed in the 5'-upstream region. Phylogenetic analysis indicated that SjM2DH has an ancient prokaryotic origin, and is probably acquired by horizontal gene transfer event. Multiple alignment and spatial structure prediction displayed a series of conserved functional residues, motifs and domains, which favored that SjM2DH belongs to the polyol-specific long-chain dehydrogenases/reductase (PSLDR family. Expressional profiles of SjM2DH in the juvenile sporophytes showed that it was influenced by saline, oxidative and desiccative factors. SjM2DH was over-expressed in Escherichia coli, and the cell-free extracts with recombinant SjM2DH displayed high activity on D-fructose reduction reaction. The analysis on SjM2DH gene structure and biochemical parameters reached a consensus that activity of SjM2DH is NADH-dependent and metal ion-independent. The characterization of SjM2DH showed that M2DH is a new member of PSLDR family and play an important role in mannitol metabolism in S. japonica.

  4. Assessment of a land-locked Atlantic salmon (Salmo salar L.) population as a potential genetic resource with a focus on long-chain polyunsaturated fatty acid biosynthesis.

    Science.gov (United States)

    Betancor, M B; Olsen, R E; Solstorm, D; Skulstad, O F; Tocher, D R

    2016-03-01

    The natural food for Atlantic salmon (Salmo salar) in freshwater has relatively lower levels of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) than found in prey for post-smolt salmon in seawater. Land-locked salmon such as the Gullspång population feed exclusively on freshwater type lipids during its entire life cycle, a successful adaptation derived from divergent evolution. Studying land-locked populations may provide insights into the molecular and genetic control mechanisms that determine and regulate n-3 LC-PUFA biosynthesis and retention in Atlantic salmon. A two factorial study was performed comparing land-locked and farmed salmon parr fed diets formulated with fish or rapeseed oil for 8 weeks. The land-locked parr had higher capacity to synthesise n-3 LC-PUFA as indicated by higher expression and activity of desaturase and elongase enzymes. The data suggested that the land-locked salmon had reduced sensitivity to dietary fatty acid composition and that dietary docosahexaenoic acid (DHA) did not appear to suppress expression of LC-PUFA biosynthetic genes or activity of the biosynthesis pathway, probably an evolutionary adaptation to a natural diet lower in DHA. Increased biosynthetic activity did not translate to enhanced n-3 LC-PUFA contents in the flesh and diet was the only factor affecting this parameter. Additionally, high lipogenic and glycolytic potentials were found in land-locked salmon, together with decreased lipolysis which in turn could indicate increased use of carbohydrates as an energy source and a sparing of lipid. PMID:26732752

  5. Characterization of Oilseed Lipids from “DHA-Producing Camelina sativa”: A New Transformed Land Plant Containing Long-Chain Omega-3 Oils

    Directory of Open Access Journals (Sweden)

    Maged P. Mansour

    2014-02-01

    Full Text Available New and sustainable sources of long-chain (LC, ≥C20 omega-3 oils containing DHA (docosahexaenoic acid, 22:6ω3 are required to meet increasing demands. The lipid content of the oilseed of a novel transgenic, DHA-producing land plant, Camelina sativa, containing microalgal genes able to produce LC omega-3 oils, contained 36% lipid by weight with triacylglycerols (TAG as the major lipid class in hexane extracts (96% of total lipid. Subsequent chloroform-methanol (CM extraction recovered further lipid (~50% polar lipid, comprising glycolipids and phospholipids and residual TAG. The main phospholipid species were phosphatidyl choline and phosphatidyl ethanolamine. The % DHA was: 6.8% (of total fatty acids in the TAG-rich hexane extract and 4.2% in the polar lipid-rich CM extract. The relative level of ALA (α-linolenic acid, 18:3ω3 in DHA-camelina seed was higher than the control. Major sterols in both DHA- and control camelina seeds were: sitosterol, campesterol, cholesterol, brassicasterol and isofucosterol. C16–C22 fatty alcohols, including iso-branched and odd-chain alcohols were present, including high levels of iso-17:0, 17:0 and 19:0. Other alcohols present were: 16:0, iso-18:0, 18:0 and 18:1 and the proportions varied between the hexane and CM extracts. These iso-branched odd-chain fatty alcohols, to our knowledge, have not been previously reported. These components may be derived from wax esters, or free fatty alcohols.

  6. Extensive esterification of adrenal C19-delta 5-sex steroids to long-chain fatty acids in the ZR-75-1 human breast cancer cell line

    International Nuclear Information System (INIS)

    Estrogen-sensitive human breast cancer cells (ZR-75-1) were incubated with the 3H-labeled adrenal C19-delta 5-steroids dehydroepiandrosterone (DHEA) and its fully estrogenic derivative, androst-5-ene-3 beta,17 beta-diol (delta 5-diol) for various time intervals. When fractionated by solvent partition, Sephadex LH-20 column chromatography and silica gel TLC, the labeled cell components were largely present (40-75%) in three highly nonpolar, lipoidal fractions. Mild alkaline hydrolysis of these lipoidal derivatives yielded either free 3H-labeled DHEA or delta 5-diol. The three lipoidal fractions cochromatographed with the synthetic DHEA 3 beta-esters, delta 5-diol 3 beta (or 17 beta)-monoesters and delta 5-diol 3 beta,17 beta-diesters of long-chain fatty acids. DHEA and delta 5-diol were mainly esterified to saturated and mono-unsaturated fatty acids. For delta 5-diol, the preferred site of esterification of the fatty acids is the 3 beta-position while some esterification also takes place at the 17 beta-position. Time course studies show that ZR-75-1 cells accumulate delta 5-diol mostly (greater than 95%) as fatty acid mono- and diesters while DHEA is converted to delta 5-diol essentially as the esterified form. Furthermore, while free C19-delta 5-steroids rapidly diffuse out of the cells after removal of the precursor [3H]delta 5-diol, the fatty acid ester derivatives are progressively hydrolyzed, and DHEA and delta 5-diol thus formed are then sulfurylated prior to their release into the culture medium. The latter process however is rate-limited, since new steady-state levels of free steroids and fatty acid esters are rapidly reached and maintained for extended periods of time after removal of precursor, thus maintaining minimal concentrations of intracellular steroids

  7. Extensive esterification of adrenal C19-delta 5-sex steroids to long-chain fatty acids in the ZR-75-1 human breast cancer cell line

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, R.; Poirier, D.; Merand, Y.; Theriault, C.; Belanger, A.; Labrie, F.

    1989-06-05

    Estrogen-sensitive human breast cancer cells (ZR-75-1) were incubated with the 3H-labeled adrenal C19-delta 5-steroids dehydroepiandrosterone (DHEA) and its fully estrogenic derivative, androst-5-ene-3 beta,17 beta-diol (delta 5-diol) for various time intervals. When fractionated by solvent partition, Sephadex LH-20 column chromatography and silica gel TLC, the labeled cell components were largely present (40-75%) in three highly nonpolar, lipoidal fractions. Mild alkaline hydrolysis of these lipoidal derivatives yielded either free 3H-labeled DHEA or delta 5-diol. The three lipoidal fractions cochromatographed with the synthetic DHEA 3 beta-esters, delta 5-diol 3 beta (or 17 beta)-monoesters and delta 5-diol 3 beta,17 beta-diesters of long-chain fatty acids. DHEA and delta 5-diol were mainly esterified to saturated and mono-unsaturated fatty acids. For delta 5-diol, the preferred site of esterification of the fatty acids is the 3 beta-position while some esterification also takes place at the 17 beta-position. Time course studies show that ZR-75-1 cells accumulate delta 5-diol mostly (greater than 95%) as fatty acid mono- and diesters while DHEA is converted to delta 5-diol essentially as the esterified form. Furthermore, while free C19-delta 5-steroids rapidly diffuse out of the cells after removal of the precursor (3H)delta 5-diol, the fatty acid ester derivatives are progressively hydrolyzed, and DHEA and delta 5-diol thus formed are then sulfurylated prior to their release into the culture medium. The latter process however is rate-limited, since new steady-state levels of free steroids and fatty acid esters are rapidly reached and maintained for extended periods of time after removal of precursor, thus maintaining minimal concentrations of intracellular steroids.

  8. Characterization of oilseed lipids from "DHA-producing Camelina sativa": a new transformed land plant containing long-chain omega-3 oils.

    Science.gov (United States)

    Mansour, Maged P; Shrestha, Pushkar; Belide, Srinivas; Petrie, James R; Nichols, Peter D; Singh, Surinder P

    2014-01-01

    New and sustainable sources of long-chain (LC, ≥C₂₀) omega-3 oils containing DHA (docosahexaenoic acid, 22:6ω3) are required to meet increasing demands. The lipid content of the oilseed of a novel transgenic, DHA-producing land plant, Camelina sativa, containing microalgal genes able to produce LC omega-3 oils, contained 36% lipid by weight with triacylglycerols (TAG) as the major lipid class in hexane extracts (96% of total lipid). Subsequent chloroform-methanol (CM) extraction recovered further lipid (~50% polar lipid, comprising glycolipids and phospholipids) and residual TAG. The main phospholipid species were phosphatidyl choline and phosphatidyl ethanolamine. The % DHA was: 6.8% (of total fatty acids) in the TAG-rich hexane extract and 4.2% in the polar lipid-rich CM extract. The relative level of ALA (α-linolenic acid, 18:3ω3) in DHA-camelina seed was higher than the control. Major sterols in both DHA- and control camelina seeds were: sitosterol, campesterol, cholesterol, brassicasterol and isofucosterol. C₁₆-C₂₂ fatty alcohols, including iso-branched and odd-chain alcohols were present, including high levels of iso-17:0, 17:0 and 19:0. Other alcohols present were: 16:0, iso-18:0, 18:0 and 18:1 and the proportions varied between the hexane and CM extracts. These iso-branched odd-chain fatty alcohols, to our knowledge, have not been previously reported. These components may be derived from wax esters, or free fatty alcohols. PMID:24566436

  9. Long-chain n-3 fatty acids enhance neonatal insulin-regulated protein metabolism in piglets by differentially altering muscle lipid composition.

    Science.gov (United States)

    Bergeron, Karen; Julien, Pierre; Davis, Teresa A; Myre, Alexandre; Thivierge, M Carole

    2007-11-01

    This study investigated the role of long-chain n-3 polyunsaturated fatty acids (LCn-3PUFAs) of muscle phospholipids in the regulation of neonatal metabolism. Twenty-eight piglets were weaned at 2 days of age and raised on one of two milk formulas that consisted of either a control formula supplying 0% or a formula containing 3.5% LCn-3PUFAs until 10 or 28 days of age. There was a developmental decline in the insulin sensitivity of amino acid disposal in control pigs during the first month of life, with a slope of -2.24 micromol.kg(-1).h(-1) (P = 0.01) per unit of insulin increment, as assessed using hyperinsulinemic-euglycemic-euaminoacidemic clamps. LCn-3PUFA feeding blunted this developmental decline, resulting in differing insulin sensitivities (P < 0.001). When protein metabolism was assessed under parenteral feeding-induced hyperinsulinemia, LCn-3PUFAs reduced by 16% whole body oxidative losses of amino acids (from 238 to 231 micromol.kg(-1).h(-1); P = 0.06), allowing 41% more amino acids to accrete into body proteins (from 90 to 127 micromol.kg(-1).h(-1); P = 0.06). The fractional synthetic rate of muscle mixed proteins remained unaltered by the LCn-3PUFA feeding. However, LCn-3PUFAs retarded a developmental increase in the essential-to-nonessential amino acid ratio of the muscle intracellular free pool (P = 0.05). Overall, alterations in metabolism were concomitant with a preferential incorporation of LCn-3PUFAs into muscle total membrane phospholipids (P < 0.001), in contrast to intramuscular triglycerides. These results underscore the potential role of LCn-3PUFAs as regulators of different aspects of protein metabolism in the neonate. PMID:17673528

  10. What Is the Most Effective Way of Increasing the Bioavailability of Dietary Long Chain Omega-3 Fatty Acids—Daily vs. Weekly Administration of Fish Oil?

    Directory of Open Access Journals (Sweden)

    Samaneh Ghasemifard

    2015-07-01

    Full Text Available The recommendations on the intake of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA vary from eating oily fish (“once to twice per week” to consuming specified daily amounts of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA (“250–500 mg per day”. It is not known if there is a difference in the uptake/bioavailability between regular daily consumption of supplementsvs. consuming fish once or twice per week. In this study, the bioavailability of a daily dose of n-3 LC-PUFA (Constant treatment, representing supplements, vs. a large weekly dose of n-3 LC-PUFA (Spike treatment, representing consuming once or twice per week, was assessed. Six-week old healthy male Sprague-Dawley rats were fed either a Constant treatment, a Spike treatment or Control treatment (no n-3 LC-PUFA, for six weeks. The whole body, tissues and faeces were analysed for fatty acid content. The results showed that the major metabolic fate of the n-3 LC-PUFA (EPA+docosapentaenoic acid (DPA + DHA was towards catabolism (β-oxidation accounting for over 70% of total dietary intake, whereas deposition accounted less than 25% of total dietary intake. It was found that significantly more n-3 LC-PUFA were β-oxidised when originating from the Constant treatment (84% of dose, compared with the Spike treatment (75% of dose. Conversely, it was found that significantly more n-3 LC-PUFA were deposited when originating from the Spike treatment (23% of dose, than from the Constant treatment (15% of dose. These unexpected findings show that a large dose of n-3 LC-PUFA once per week is more effective in increasing whole body n-3 LC-PUFA content in rats compared with a smaller dose delivered daily.

  11. Enzymatic Synthesis of Palm Alkyl Ester Using Dialkyl Carbonate as an Alkyl Donors

    Directory of Open Access Journals (Sweden)

    Roila Awang

    2010-01-01

    Full Text Available Problem statement: Though efficient in terms of reaction yield and time, the chemical approach to synthesizing alkyl ester has drawback such as difficulties in the recovery of glycerol and the need for removal of salt residue. On the other hand, biocatalyst allow for synthesis of specific alkyl esters and easy recovery of glycerol. However, the solvent-free alcoholysis, does not give high conversion. The same problem was also found when ethyl or methyl acetate was used as acyl acceptors. Approach: Lipase catalyzed transesterification of oil and dialkyl carbonate was predicted to give higher conversion in solvent free reaction system. Results: Alkyl esters were synthesized enzymatically to overcome the problems associated with chemical processes. In this study, dialkyl carbonates were used as an alkyl donor for the production of alkyl ester. Nine commercial lipases were tested for their suitability for the reaction system. Among the lipase tested, Novozym 435 was chosen for optimization study because of their higher activity. In a solvent-free reaction system, the ester formation using dialkyl carbonate was 6 times higher than using ethanol and methanol. The effect of various reaction parameters such as temperature, amount of enzyme, organic solvent and structure of substrates were studied to determine optimal condition. The optimal conditions of ester formation were reaction temperature at 60°C, reaction time at 8 h, enzyme amount of 10% (w/w of oil and 0.2% wt added water. Conclusion: Solvent-free lipase catalyzed transesterification of palm kernel oil and dialkyl carbonates gave higher conversion of ester compared to the reaction using short chain alcohol as an alkyl donors.

  12. Oxidative Umpolung α‐Alkylation of Ketones

    DEFF Research Database (Denmark)

    Shneider, O. Svetlana; Pisarevsky, Evgeni; Fristrup, Peter; Szpilman, Alex M.

    2015-01-01

    We disclose a hypervalent iodine mediated α-alkylative umpolung reaction of carbonyl compounds with dialkylzinc as the alkyl source. The reaction is applicable to all common classes of ketones including 1,3-dicarbonyl compounds and regular ketones via their lithium enolates. The α-alkylated carbo......-alkylated carbonyl products are formed in up to 93% yield. An ionic mechanism is inferred based on meticulous analysis, NMR studies, trapping and crossover experiments, and computational studies.......We disclose a hypervalent iodine mediated α-alkylative umpolung reaction of carbonyl compounds with dialkylzinc as the alkyl source. The reaction is applicable to all common classes of ketones including 1,3-dicarbonyl compounds and regular ketones via their lithium enolates. The α...

  13. Effect of long chain omega-3 polyunsaturated fatty acids on inflammation and metabolic markers in hypertensive and/or diabetic obese adults: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Mohammed S. Ellulu

    2016-01-01

    Full Text Available Background: Obesity is a degree of excess weight that predisposes people to metabolic syndromes via an inflammatory mechanism. Hypertensive and diabetic people have higher risks of developing systemic inflammation. Long chain omega-3 polyunsaturated fatty acids (LC ω-3 PUFAs can reduce the cardiovascular events and help against inflammation. Objective: To identify the effects of LC ω-3 PUFAs on reducing the levels of inflammatory markers on hypertensive and/or diabetic obese adults. Materials and methods: Sixty-four patients, who were hypertensive and/or diabetic obese with high levels of inflammatory markers, from primary healthcare centers of Gaza City, Palestine, enrolled in two groups of an open-label, parallel, randomized, controlled trial for 8 weeks. Thirty-three patients were in the control group, and 31 patients were in the experimental group. The experimental group was treated with a daily dose of 300 mg eicosapentaenoic acid and 200 mg of docosahexaenoic acid. Results: Treatment with LC ω-3 PUFAs significantly reduced the level of high sensitivity C reactive protein (hs-CRP [14.78±10.7 to 8.49±6.69 mg/L, p<0.001], fasting blood glucose (FBG [178.13±58.54 to 157.32±59.77 mg/dL, p=0.024], and triglyceride (TG [209.23±108.3 to 167.0±79.9 mg/dL, p<0.05] after 8 weeks of treatment, whereas no significant changes appeared in interleukin 6 (IL-6 and total cholesterol (TC. In the control group, significant reduction was detected for FBG [187.15±64.8 to 161.91±37.9 mg/dL, p<0.05] and TG [202.91±107.0 to 183.45±95.82 mg/dL, p<0.05], and no changes for hs-CRP, IL-6, or TC. By comparing the experimental group with the changes of control group at the endpoint, LC ω-3 PUFAs did not reach the clinical significance in treating effectiveness for any of the clinical variables. Conclusion: LC ω-3 PUFAs have recommended effects on health; the obtained results can improve the role of LC ω-3 PUFAs as a protective factor on inflammation and

  14. Bioconversion of α-linolenic acid into n-3 long-chain polyunsaturated fatty acid in hepatocytes and ad hoc cell culture optimisation.

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    Ramez Alhazzaa

    Full Text Available This study aimed to establish optimal conditions for a cell culture system that would allow the measurement of 18:3n-3 (ALA bioconversion into n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA, and to determine the overall pathway kinetics. Using rat hepatocytes (FaO as model cells, it was established that a maximum 20:5n-3 (EPA production from 50 µM ALA initial concentration was achieved after 3 days of incubation. Next, it was established that a gradual increase in the ALA concentration from 0 up to 125 µM lead to a proportional increase in EPA, without concomitant increase in further elongated or desaturated products, such as 22:5n-3 (DPA and 22:6n-3 (DHA in 3 day incubations. Of interest, ALA bioconversion products were observed in the culture medium. Therefore, in vitro experiments disregarding the medium fatty acid content are underestimating the metabolism efficiency. The novel application of the fatty acid mass balance (FAMB method on cell culture system (cells with medium enabled quantifying the apparent enzymatic activities for the biosynthesis of n-3 LC-PUFA. The activity of the key enzymes was estimated and showed that, under these conditions, 50% (Km of the theoretical maximal (V max = 3654 µmol.g(-1 of cell protein.hour(-1 Fads2 activity on ALA can be achieved with 81 µM initial ALA. Interestingly, the apparent activity of Elovl2 (20:5n-3 elongation was the slowest amongst other biosynthesis steps. Therefore, the possible improvement of Elovl2 activity is suggested toward a more efficient DHA production from ALA. The present study proposed and described an ad hoc optimised cell culture conditions and methodology towards achieving a reliable experimental platform, using FAMB, to assist in studying the efficiency of ALA bioconversion into n-3 LC-PUFA in vitro. The FAMB proved to be a powerful and inexpensive method to generate a detailed description of the kinetics of n-3 LC-PUFA biosynthesis enzymes activities in vitro.

  15. A post-GWAS confirming the SCD gene associated with milk medium- and long-chain unsaturated fatty acids in Chinese Holstein population.

    Science.gov (United States)

    Li, C; Sun, D; Zhang, S; Liu, L; Alim, M A; Zhang, Q

    2016-08-01

    The stearoyl-CoA desaturase (delta-9-desaturase) gene encodes a key enzyme in the cellular biosynthesis of monounsaturated fatty acids. In our initial genome-wide association study (GWAS) of Chinese Holstein cows, 19 SNPs fell in a 1.8-Mb region (20.3-22.1 Mb) on chromosome 26 underlying the SCD gene and were highly significantly associated with C14:1 or C14 index. The aims of this study were to verify whether the SCD gene has significant genetic effects on milk fatty acid composition in dairy cattle. By resequencing the entire coding region of the bovine SCD gene, a total of six variations were identified, including three coding variations (g.10153G>A, g.10213T>C and g.10329C>T) and three intronic variations (g.6926A>G, g.8646G>A and g.16158G>C). The SNP in exon 3, g.10329C>T, was predicted to result in an amino acid replacement from alanine (GCG) to valine (GTG) in the SCD protein. An association study for 16 milk fatty acids using 346 Chinese Holstein cows with accurate phenotypes and genotypes was performed using the mixed animal model with the proc mixed procedure in sas 9.2. All six detected SNPs were revealed to be associated with six medium- and long-chain unsaturated fatty acids (P = 0.0457 to P analysis revealed significant associations of the haplotypes encompassing the six SCD SNPs and one SNP (rs109923480) in a GWAS with C14:1, C14 index, C16:1 and C16 index (P = 0.0011 to P < 0.0001). In summary, our findings provide replicate evidence for our previous GWAS and demonstrate that variants in the SCD gene are significantly associated with milk fatty acid composition in dairy cattle, which provides clear evidence for an increased understanding of milk fatty acid synthesis and enhances opportunities to improve milk-fat composition in dairy cattle. PMID:26970560

  16. Effects of flaxseed and chia seed on ruminal fermentation, nutrient digestibility, and long-chain fatty acid flow in a dual-flow continuous culture system.

    Science.gov (United States)

    Silva, L G; Bunkers, J; Paula, E M; Shenkoru, T; Yeh, Y; Amorati, B; Holcombe, D; Faciola, A P

    2016-04-01

    Flaxseed (FS) and chia seed (CS) are oilseeds rich in omega-3 fatty acids, which may change meat and milk composition when added to ruminants' diets and may have health benefits for humans. Literature on the effects of CS supplementation on ruminal metabolism is nonexistent. A dual-flow continuous culture fermenter system consisting of 6 fermenters was used to assess the effect of FS and CS supplementation in an alfalfa hay-based diet on ruminal fermentation, nutrient digestibility, microbial protein synthesis, and long-chain fatty acid flow. Diets were randomly assigned to fermenters in a replicated 3 × 3 Latin square design, with 3 consecutive periods of 10 d each, consisting of 7 d for diet adaptation and 3 d for sample collection. Each fermenter was fed a total of 72 g of DM/d divided in 6 equal portions. Treatments were 1) alfalfa hay + calcium soaps of palm oil fatty acid (MEG; 69.3 g DM/d of alfalfa hay plus 2.7 g DM/d of calcium soaps of palm oil fatty acid), 2) alfalfa hay + FS (FLAX; 68.4 g DM/d of alfalfa hay plus 3.6 g DM/d of ground FS), and 3) alfalfa hay + CS (CHIA; 68.04 g DM/d of alfalfa hay plus 3.96 g DM/d of ground CS). Dietary treatments had similar amounts of total fat, and fat supplements were ground to 2-mm diameter. Effluents from the last 3 d of incubation were composited for analyses. Data were analyzed using the MIXED procedure of SAS. Ruminal apparent and true nutrient digestibility of all nutrients did not differ ( > 0.05) among treatments. Compared with MEG, FLAX and CHIA increased the flows of C18:3 -3, C20:4 -6, and total PUFA ( 0.05) by treatments. Lastly, there were no differences ( > 0.05) among diets for total VFA concentration and molar proportions of individual VFA. Results from this study indicate that FS and CS supplementation did not impair ruminal fermentation, digestibility, microbial efficiency, and ruminal N metabolism. Overall, CS appears to be as effective as FS as a fat source when added to ruminants' diets using a

  17. Mitochondrial long chain fatty acid oxidation, fatty acid translocase/CD36 content and carnitine palmitoyltransferase I activity in human skeletal muscle during aerobic exercise

    Science.gov (United States)

    Holloway, Graham P; Bezaire, Veronic; Heigenhauser, George J F; Tandon, Narendra N; Glatz, Jan F C; Luiken, Joost J F P; Bonen, Arend; Spriet, Lawrence L

    2006-01-01

    Mitochondrial fatty acid transport is a rate-limiting step in long chain fatty acid (LCFA) oxidation. In rat skeletal muscle, the transport of LCFA at the level of mitochondria is regulated by carnitine palmitoyltransferase I (CPTI) activity and the content of malonyl-CoA (M-CoA); however, this relationship is not consistently observed in humans. Recently, fatty acid translocase (FAT)/CD36 was identified on mitochondria isolated from rat and human skeletal muscle and found to be involved in LCFA oxidation. The present study investigated the effects of exercise (120 min of cycling at ∼60% V̇O2peak) on CPTI palmitoyl-CoA and M-CoA kinetics, and on the presence and functional significance of FAT/CD36 on skeletal muscle mitochondria. Whole body fat oxidation rates progressively increased during exercise (P < 0.05), and concomitantly M-CoA inhibition of CPTI was progressively attenuated. Compared to rest, 120 min of cycling reduced (P < 0.05) the inhibition of 0.7, 2, 5 and 10 μm M-CoA by 16%, 21%, 30% and 34%, respectively. Whole body fat oxidation and palmitate oxidation rates in isolated mitochondria progressively increased (P < 0.05) during exercise, and were positively correlated (r = 0.78). Mitochondrial FAT/CD36 protein increased by 63% (P < 0.05) during exercise and was significantly (P < 0.05) correlated with mitochondrial palmitate oxidation rates at all time points (r= 0.41). However, the strongest (P < 0.05) correlation was observed following 120 min of cycling (r= 0.63). Importantly, the addition of sulfo-N-succimidyloleate, a specific inhibitor of FAT/CD36, reduced mitochondrial palmitate oxidation to ∼20%, indicating FAT/CD36 is functionally significant with respect to LCFA oxidation. We hypothesize that exercise-induced increases in fatty acid oxidation occur as a result of an increased ability to transport LCFA into mitochondria. We further suggest that decreased CPTI M-CoA sensitivity and increased mitochondrial FAT/CD36 protein are both

  18. Low blood long chain omega-3 fatty acids in UK children are associated with poor cognitive performance and behavior: a cross-sectional analysis from the DOLAB study.

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    Paul Montgomery

    Full Text Available BACKGROUND: Omega-3 long-chain polyunsaturated fatty acids (LC-PUFA, especially DHA (docosahexaenonic acid are essential for brain development and physical health. Low blood Omega-3 LC-PUFA have been reported in children with ADHD and related behavior/learning difficulties, as have benefits from dietary supplementation. Little is known, however, about blood fatty acid status in the general child population. We therefore investigated this in relation to age-standardized measures of behavior and cognition in a representative sample of children from mainstream schools. PARTICIPANTS: 493 schoolchildren aged 7-9 years from mainstream Oxfordshire schools, selected for below average reading performance in national assessments at age seven. METHOD: Whole blood fatty acids were obtained via fingerstick samples. Reading and working memory were assessed using the British Ability Scales (II. Behaviour (ADHD-type symptoms was rated using the revised Conners' rating scales (long parent and teacher versions. Associations were examined and adjusted for relevant demographic variables. RESULTS: DHA and eicosapentaenoic acid (EPA, accounted for only 1.9% and 0.55% respectively of total blood fatty acids, with DHA showing more individual variation. Controlling for sex and socio-economic status, lower DHA concentrations were associated with poorer reading ability (std. OLS coeff. = 0.09, p = <.042 and working memory performance (0.14, p = <.001. Lower DHA was also associated with higher levels of parent rated oppositional behavior and emotional lability (-0.175, p = <.0001 and -0.178, p = <.0001. CONCLUSIONS: In these healthy UK children with below average reading ability, concentrations of DHA and other Omega-3 LC-PUFA were low relative to adult cardiovascular health recommendations, and directly related to measures of cognition and behavior. These findings require confirmation, but suggest that the benefits from dietary supplementation with

  19. Effects of two different dietary sources of long chain omega-3, highly unsaturated fatty acids on incorporation into the plasma, red blood cell, and skeletal muscle in horses.

    Science.gov (United States)

    Hess, T M; Rexford, J K; Hansen, D K; Harris, M; Schauermann, N; Ross, T; Engle, T E; Allen, K G D; Mulligan, C M

    2012-09-01

    The objective of this study was to examine the effects of different sources of dietary omega-3 (n-3) fatty acid supplementation on plasma, red blood cell, and skeletal muscle fatty acid compositions in horses. Twenty-one mares were blocked by age, BW, and BCS and assigned to 1 of 3 dietary treatments with 7 mares per treatment. Dietary treatments were: 1) control or no fatty acid supplement (CON), 2) 38 g of n-3 long chain, highly unsaturated fatty acid (LCHUFA) supplement/d provided by algae and fish oil (MARINE) containing alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA), and 3) 38 g of n-3 LCHUFA supplement/d provided by a flaxseed meal (FLAX) containing ALA. Each supplement was added to a basal diet consisting of hay and barley and was fed for 90 d. Blood samples and muscle middle gluteal biopsies were taken at d 0, 30, 60 and 90 of supplementation. Plasma, red blood cell and skeletal muscle fatty acid profiles were determined via gas chromatography. Plasma linoleic acid (LA) and ALA were at least 10 and 60% less (P < 0.01), respectively, in the MARINE compared with the FLAX and CON groups. Plasma EPA and DHA were only detected in the MARINE group, and EPA increased 40% (P < 0.001) from d 30 to 60, and DHA 19% (P < 0.01) from d 30 to 90. Red blood cell LA and ALA were not different among treatments. Red blood cell EPA and DHA were only detected in the MARINE group, where EPA increased 38% (P < 0.01) from d 30 to 60, and DHA increased 56% (P < 0.001) between d 30 and 90. Skeletal muscle LA was at least 17% less (P < 0.001) in the MARINE group compared with the other treatments. Skeletal muscle ALA was 15% less (P = 0.03) in the MARINE group compared with FLAX and CON groups. Skeletal muscle EPA was at least 25% greater (P < 0.001) in MARINE group compared with other treatments and increased (P < 0.001) by 71% from d 30 to 60. Skeletal muscle DHA was at least 57% greater (P < 0.001) in the MARINE

  20. Reduction of novel circulating long-chain fatty acids in colorectal cancer patients is independent of tumor burden and correlates with age

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    Tomonaga Takeshi

    2010-11-01

    Full Text Available Abstract Background Serum levels of novel hydroxy polyunsaturated ultra long-chain fatty acids (hPULCFAs have been previously shown to be reduced in pre-treatment CRC patients compared to disease-free subjects, independent of disease stage. However, whether reduced levels of hPULCFAs result from the presence of cancer is currently unknown, as is the distribution of hPULCFAs in the general population. The following studies were carried out to assess whether conventional therapy would result in restoration of systemic hPULCFAs in CRC patients, and to investigate the relationship between hPULCFA levels and age. Methods Tandem mass spectrometry was used to determine serum levels of the 28 carbon-containing hPULCFA C28H46O4 (CRC-446 in the following cohorts: two independent Japanese CRC populations following surgical tumor removal (n = 86, a North American Caucasian CRC cohort (n = 150 following post-surgery combination chemo/radiation therapy, 990 randomly selected anonymized serum samples from subjects ranging between 11 and 99 years of age, as well as longitudinally collected serum samples from healthy normals (n = 8, up to 90 weeks and stage IV CRC subjects on combination therapy (n = 12, up to 63 weeks. Results Serum CRC-446 levels in CRC subjects were significantly lower than controls (mean of 0.297 ± 0.07 ug/ml in controls versus 0.092 ± 0.03 in CRCs, p 0.05 between pre vs post surgery. CRC-446 levels showed a strong inverse association with age (p Conclusions Our findings show that CRC-446 levels are not affected by conventional CRC treatment and inversely correlate with age, which suggest that reduced serum CRC-446 levels likely exist prior to the development of CRC. Extrapolation of the results to a simple screening scenario showed that, compared to fecal blood testing, pre-colonoscopy screening using serum CRC-446 levels would require 80% fewer colonoscopies, would identify risk in subjects under the age of 50, and would result in

  1. The Effects of n-3 Long-Chain Polyunsaturated Fatty Acid Supplementation on Biomarkers of Kidney Injury in Adults With Diabetes

    Science.gov (United States)

    Miller, Edgar R.; Juraschek, Stephen P.; Anderson, Cheryl A.; Guallar, Eliseo; Henoch-Ryugo, Karen; Charleston, Jeanne; Turban, Sharon; Bennett, Michael R.; Appel, Lawrence J.

    2013-01-01

    OBJECTIVE Long-chain n-3 polyunsaturated fatty acid (n-3 PUFA) supplements may have renoprotective effects in patients with diabetes, but previous trials have been inconsistent. We performed a randomized controlled trial of n-3 PUFA supplementation on urine albumin excretion and markers of kidney injury in adults with type 2 diabetes. RESEARCH DESIGN AND METHODS We conducted a randomized, placebo-controlled, two-period crossover trial to test the effects of 4 g/day of n-3 PUFA supplementation on markers of glomerular filtration and kidney injury in adults with adult-onset diabetes and greater than or equal to trace amounts of proteinuria. Each period lasted 6 weeks and was separated by a 2-week washout. The main outcome was urine albumin excretion and, secondarily, markers of kidney injury (kidney injury molecule-1, N-acetyl β-d-glucosaminidase [NAG], neutrophil gelatinase-associated lipocalin [NGAL], and liver fatty acid–binding protein [LFABP]), serum markers of kidney function (cystatin C, β2-microglobulin, and creatinine), and estimated glomerular filtration rate (eGFR). RESULTS Of the 31 participants, 29 finished both periods. A total of 55% were male, and 61% were African American; mean age was 67 years. At baseline, mean BMI was 31.6 kg/m2, median eGFR was 76.9 mL/min/1.73 m2, and median 24-h urine albumin excretion was 161 mg/day. Compared with placebo, n-3 PUFA had nonsignificant effects on urine albumin excretion (−7.2%; 95% CI −20.6 to 8.5; P = 0.35) and significant effects on urine NGAL excretion (−16% [−29.1 to −0.5%]; P = 0.04). There was no effect on serum markers of kidney function or eGFR. In subgroup analyses, there were significant decreases in 24-h urinary excretion of albumin, NGAL, LFABP, and NAG among participants taking medications that block the renin-angiotensin-aldosterone system (RAAS). CONCLUSIONS These results suggest a potential effect of n-3 PUFA supplementation on markers of kidney injury in patients with diabetes and

  2. The effects of n-3 long-chain polyunsaturated fatty acid supplementation on biomarkers of kidney injury in adults with diabetes: results of the GO-FISH trial.

    Science.gov (United States)

    Miller, Edgar R; Juraschek, Stephen P; Anderson, Cheryl A; Guallar, Eliseo; Henoch-Ryugo, Karen; Charleston, Jeanne; Turban, Sharon; Bennett, Michael R; Appel, Lawrence J

    2013-06-01

    OBJECTIVE Long-chain n-3 polyunsaturated fatty acid (n-3 PUFA) supplements may have renoprotective effects in patients with diabetes, but previous trials have been inconsistent. We performed a randomized controlled trial of n-3 PUFA supplementation on urine albumin excretion and markers of kidney injury in adults with type 2 diabetes. RESEARCH DESIGN AND METHODS We conducted a randomized, placebo-controlled, two-period crossover trial to test the effects of 4 g/day of n-3 PUFA supplementation on markers of glomerular filtration and kidney injury in adults with adult-onset diabetes and greater than or equal to trace amounts of proteinuria. Each period lasted 6 weeks and was separated by a 2-week washout. The main outcome was urine albumin excretion and, secondarily, markers of kidney injury (kidney injury molecule-1, N-acetyl β-d-glucosaminidase [NAG], neutrophil gelatinase-associated lipocalin [NGAL], and liver fatty acid-binding protein [LFABP]), serum markers of kidney function (cystatin C, β2-microglobulin, and creatinine), and estimated glomerular filtration rate (eGFR). RESULTS Of the 31 participants, 29 finished both periods. A total of 55% were male, and 61% were African American; mean age was 67 years. At baseline, mean BMI was 31.6 kg/m(2), median eGFR was 76.9 mL/min/1.73 m(2), and median 24-h urine albumin excretion was 161 mg/day. Compared with placebo, n-3 PUFA had nonsignificant effects on urine albumin excretion (-7.2%; 95% CI -20.6 to 8.5; P = 0.35) and significant effects on urine NGAL excretion (-16% [-29.1 to -0.5%]; P = 0.04). There was no effect on serum markers of kidney function or eGFR. In subgroup analyses, there were significant decreases in 24-h urinary excretion of albumin, NGAL, LFABP, and NAG among participants taking medications that block the renin-angiotensin-aldosterone system (RAAS). CONCLUSIONS These results suggest a potential effect of n-3 PUFA supplementation on markers of kidney injury in patients with diabetes and early

  3. Maternal but not fetal FADS gene variants modify the association between maternal long-chain PUFA intake in pregnancy and birth weight.

    Science.gov (United States)

    Moltó-Puigmartí, Carolina; van Dongen, Martien C J M; Dagnelie, Pieter C; Plat, Jogchum; Mensink, Ronald P; Tan, Frans E S; Heinrich, Joachim; Thijs, Carel

    2014-09-01

    Several studies have shown a positive association between maternal fish intake in pregnancy and pregnancy duration and child birth weight (BW), probably due to fish n-3 (ω-3) long-chain polyunsaturated fatty acids (LC-PUFAs). n-3 LC-PUFAs can also be synthesized endogenously, and their synthesis depends on single nucleotide polymorphisms (SNPs) in the fatty acid desaturase (FADS) gene encoding for FADS. We assessed the associations of maternal docosahexaenoic acid (DHA) intake in pregnancy with pregnancy duration and BW and investigated whether these associations are modified by maternal or fetal FADS SNP genotypes. We hypothesized that we would find stronger associations in minor allele homozygous mothers or fetuses due to their lower n-3 LC-PUFA endogenous synthesis and hence higher dependence on dietary supply. Data on maternal diet, pregnancy duration, and BW were available for 2622 mother-child pairs from the KOALA (Kind, Ouders en gezondheid: Aandacht voor Leefstijl en Aanleg) Birth Cohort Study. The rs174556 FADS SNP was genotyped in 1516 mothers and 1515 children. Associations and gene-diet interactions were tested with linear regression adjusting for potential confounders, including intake of other PUFAs. Women at the 75th percentile of DHA intake had 0.7-d longer pregnancies (P = 0.016) and 28-g heavier infants (P = 0.039) than did women at the 25th percentile of intake. Associations with arachidonic acid intake were of the same order but in the opposite direction. Mothers who were homozygous for the minor allele had 2-d shorter pregnancies (P = 0.035) and infants who were nearly 140 g lighter (P = 0.006) than did mothers who were major allele homozygotes. Post hoc analyses revealed that they had higher prepregnancy BMI (P = 0.020). Among the women homozygous for the minor allele, those at the 75th percentile of DHA intake had 226-g heavier infants than those at the 25th percentile of intake (P = 0.030), whereas DHA intake was not significantly

  4. Systematic Analysis of Gene Expression Alterations and Clinical Outcomes for Long-Chain Acyl-Coenzyme A Synthetase Family in Cancer.

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    Wei-Ching Chen

    Full Text Available Dysregulated lipid metabolism contributes to cancer progression. Our previous study indicates that long-chain fatty acyl-Co A synthetase (ACSL 3 is essential for lipid upregulation induced by endoplasmic reticulum stress. In this report, we aimed to identify the role of ACSL family in cancer with systematic analysis and in vitro experiment. We explored the ACSL expression using Oncomine database to determine the gene alteration during carcinogenesis and identified the association between ACSL expression and the survival of cancer patient using PrognoScan database. ACSL1 may play a potential oncogenic role in colorectal and breast cancer and play a potential tumor suppressor role in lung cancer. Co-expression analysis revealed that ACSL1 was coexpressed with MYBPH, PTPRE, PFKFB3, SOCS3 in colon cancer and with LRRFIP1, TSC22D1 in lung cancer. In accordance with PrognoScan analysis, downregulation of ACSL1 in colon and breast cancer cell line inhibited proliferation, migration, and anchorage-independent growth. In contrast, increase of oncogenic property was observed in lung cancer cell line by attenuating ACSL1. High ACSL3 expression predicted a better prognosis in ovarian cancer; in contrast, high ACSL3 predicted a worse prognosis in melanoma. ACSL3 was coexpressed with SNUPN, TRIP13, and SEMA5A in melanoma. High expression of ACSL4 predicted a worse prognosis in colorectal cancer, but predicted better prognosis in breast, brain and lung cancer. ACSL4 was coexpressed with SERPIN2, HNRNPCL1, ITIH2, PROCR, LRRFIP1. High expression of ACSL5 predicted good prognosis in breast, ovarian, and lung cancers. ACSL5 was coexpressed with TMEM140, TAPBPL, BIRC3, PTPRE, and SERPINB1. Low ACSL6 predicted a worse prognosis in acute myeloid leukemia. ACSL6 was coexpressed with SOX6 and DARC. Altogether, different members of ACSLs are implicated in diverse types of cancer development. ACSL-coexpressed molecules may be used to further investigate the role of ACSL

  5. Determining cysteine oxidation status using differential alkylation

    Science.gov (United States)

    Schilling, Birgit; Yoo, Chris B.; Collins, Christopher J.; Gibson, Bradford W.

    2004-08-01

    Oxidative damage to proteins plays a major role in aging and in the pathology of many degenerative diseases. Under conditions of oxidative stress, reactive oxygen and nitrogen species can modify key redox sensitive amino acid side chains leading to altered biological activities or structures of the targeted proteins. This in turn can affect signaling or regulatory control pathways as well as protein turnover and degradation efficiency in the proteasome. Cysteine residues are particularly susceptible to oxidation, primarily through reversible modifications (e.g., thiolation and nitrosylation), although irreversible oxidation can lead to products that cannot be repaired in vivo such as sulfonic acid. This report describes a strategy to determine the overall level of reversible cysteine oxidation using a stable isotope differential alkylation approach in combination with mass spectrometric analysis. This method employs 13C-labeled alkylating reagents, such as N-ethyl-[1,4-13C2]-maleimide, bromo-[1,2-13C2]-acetic acid and their non-labeled counterparts to quantitatively assess the level of cysteine oxidation at specific sites in oxidized proteins. The differential alkylation protocol was evaluated using standard peptides and proteins, and then applied to monitor and determine the level of oxidative damage induced by diamide, a mild oxidant. The formation and mass spectrometric analysis of irreversible cysteine acid modification will also be discussed as several such modifications have been identified in subunits of the mitochondrial electron transport chain complexes. This strategy will hopefully contribute to our understanding of the role that cysteine oxidation plays in such chronic diseases such as Parkinson's disease, where studies in animal and cell models have shown oxidative damage to mitochondrial Complex I to be a specific and early target.

  6. Identification and characterization of a novel C20-elongase gene from the marine microalgae, Pavlova viridis, and its use for the reconstitution of two pathways of long-chain polyunsatured fatty acids biosynthesis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Shi, Tonglei; Yu, Aiqun; Li, Ming; Zhang, Meng; Xing, Laijun; Li, Mingchun

    2013-08-01

    The marine microalga, Pavlova viridis, contains long-chain polyunsatured fatty acids including eicosapentaenoic acid (EPA, 20:5n-3) and docosapentaenoic acid (DPA, 22:5n-3). A full-length cDNA sequence, pvelo5, was isolated from P. viridis. From sequence alignment, the gene was homologous to fatty acyl elongases from other organisms. Heterologous expression of pvelo5 in Saccharomyces cerevisiae confirmed that it encoded a specific C20-elongase within the n-3 and n-6 pathways. Elongation activity was confined exclusively to EPA and arachidonic acid (20:4n-6). GC analysis indicated that pvelo5 could co-express with other genes for biosynthesis to reconstitute the Δ8 and Δ6 pathways. Real-time PCR results and fatty acid analysis demonstrated that long-chain polyunsatured fatty acids production by the Δ8 pathway might be more effective than that by the Δ6 pathway. PMID:23546943

  7. New Bioactive Alkyl Sulfates from Mediterranean Tunicates

    Directory of Open Access Journals (Sweden)

    Marialuisa Menna

    2012-10-01

    Full Text Available Chemical investigation of two species of marine ascidians, Aplidium elegans and Ciona edwardsii, collected in Mediterranean area, led to isolation of a series of alkyl sulfates (compounds 1–5 including three new molecules 1–3. Structures of the new metabolites have been elucidated by spectroscopic analysis. Based on previously reported cytotoxic activity of these type of molecules, compounds 1–3 have been tested for their effects on the growth of two cell lines, J774A.1 (BALB/c murine macrophages and C6 (rat glioma in vitro. Compounds 1 and 2 induced selective concentration-dependent mortality on J774A.1 cells.

  8. Bear Spray Safety Program

    Science.gov (United States)

    Blome, C.D.; Kuzniar, R.L.

    2009-01-01

    A bear spray safety program for the U.S. Geological Survey (USGS) was officially initiated by the Firearms Safety Committee to address accident prevention and to promote personnel training in bear spray and its transportation, storage, and use for defense against wild animals. Used as part of a system including firearms, or used alone for those who choose not to carry a firearm, bear spray is recognized as an effective tool that can prevent injury in a wild animal attack.

  9. Optimal Synchronizability of Bearings

    OpenAIRE

    Araújo, N. A. M.; Seybold, H.; Baram, R. M.; Herrmann, H. J.; Andrade, J. S.

    2013-01-01

    Bearings are mechanical dissipative systems that, when perturbed, relax toward a synchronized (bearing) state. Here we find that bearings can be perceived as physical realizations of complex networks of oscillators with asymmetrically weighted couplings. Accordingly, these networks can exhibit optimal synchronization properties through fine tuning of the local interaction strength as a function of node degree [Motter, Zhou, and Kurths, Phys. Rev. E 71, 016116 (2005)]. We show that, in analogy...

  10. Bearing restoration by grinding

    Science.gov (United States)

    Hanau, H.; Parker, R. J.; Zaretsky, E. V.; Chen, S. M.; Bull, H. L.

    1976-01-01

    A joint program was undertaken by the NASA Lewis Research Center and the Army Aviation Systems Command to restore by grinding those rolling-element bearings which are currently being discarded at aircraft engine and transmission overhaul. Three bearing types were selected from the UH-1 helicopter engine (T-53) and transmission for the pilot program. No bearing failures occurred related to the restoration by grinding process. The risk and cost of a bearing restoration by grinding programs was analyzed. A microeconomic impact analysis was performed.

  11. EcoBears

    DEFF Research Database (Denmark)

    Nielsen, Nick; Pedersen, Sandra Bleuenn; Sørensen, Jens Ager;

    2015-01-01

    In this paper, we introduce the EcoBears concept that aims to augment household appliances with functional and aesthetic features to promote their "use'' and "longevity of use'' to prevent their disposal. The EcoBears also aim to support the communication of environmental issues in the home setting....... We present our initial design and implementation of the EcoBears that consist of two bear modules (a mother and her cub). We also present our preliminary concept validations and lessons learned to be considered for future directions....

  12. Perfluorinated alkyl acids in the plasma of South African crocodiles (Crocodylus niloticus).

    Science.gov (United States)

    Christie, Ian; Reiner, Jessica L; Bowden, John A; Botha, Hannes; Cantu, Theresa M; Govender, Danny; Guillette, Matthew P; Lowers, Russell H; Luus-Powell, Wilmien J; Pienaar, Danie; Smit, Willem J; Guillette, Louis J

    2016-07-01

    Perfluorinated alkyl acids (PFAAs) are environmental contaminants that have been used in many products for over 50 years. Interest and concern has grown since 2000 on the widespread presence of PFAAs, when it was discovered that PFAAs were present in wildlife samples around the northern hemisphere. Since then, several studies have reported PFAAs in wildlife from many locations, including the remote regions of Antarctica and the Arctic. Although there are a multitude of studies, few have reported PFAA concentrations in reptiles and wildlife in the Southern Hemisphere. This study investigated the presence of PFAAs in the plasma of Nile crocodiles (Crocodylus niloticus) from South Africa. Crocodiles were captured from five sites in and around the Kruger National Park, South Africa, and plasma samples examined for PFAAs. Perfluorooctane sulfonate (PFOS) was the most frequent PFAA detected; with median values of 13.5 ng/g wet mass in crocodiles. In addition to PFOS, long chain perfluorinated carboxylic acids were also detected. Correlations between total length and PFAA load were investigated, as were differences in PFAA accumulation between sexes. No correlations were seen between crocodile size, nor were there sex-related differences. Spatial differences were examined and significant differences were observed in samples collected from the different sites (p < 0.05). Flag Boshielo Dam had the highest PFOS measurements, with a median concentration of 50.3 ng/g wet mass, when compared to the other sites (median concentrations at other sites below 14.0 ng/g wet mass). This suggests a point source of PFOS in this area. PMID:27038902

  13. Synthesis and structural characterisation of an yttrium-alkyl-alkylidene

    OpenAIRE

    Arnold, Polly; Green, J. C.; McMaster, J; Liddle, S.T.

    2008-01-01

    The first structurally authenticated yttrium-alkyl-alkylidene is reported; structural, spectroscopic, and theoretical analyses show that whilst the yttrium-alkylidene bond is short, it possesses a bond order less than one and is comparable to the Y-C-alkyl single bond within the same molecule.

  14. Polyfluorinated alkyl phosphate ester surfactants - current knowledge and knowledge gaps

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Rosenmai, Anna Kjerstine; Vinggaard, Anne Marie

    2014-01-01

    information on fluorochemicals. Polyfluorinated alkyl phosphate ester surfactants (PAPs) belong to the group of polyfluorinated alkyl surfactants. They have been detected in indoor dust and are widely used in food-contact materials, from which they have the ability to migrate into food. Toxicological data on...

  15. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Science.gov (United States)

    2010-07-01

    ... hydrocarbons. 721.840 Section 721.840 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  16. Clinical applications of quinone-containing alkylating agents.

    Science.gov (United States)

    Begleiter, A

    2000-11-01

    Quinone-containing alkylating agents are a class of chemical agents that have received considerable interest as anticancer drugs. These agents contain a quinone moiety that can be reduced and an alkylating group that can form covalent bonds with a variety of cellular components. The oxidation state of the quinone element can modulate the activity of the alkylating element, and reduction of the quinone is required for activation of the alkylating activity of many of these agents. The quinone element may also contribute to the cytotoxic activity of quinone-containing alkylating agents through the formation of reactive oxygen species during redox cycling. The natural product, mitomycin C, has been the most widely used quinone-containing alkylating agent in the clinic, but other quinone-containing alkylating agents like porfiromycin, diaziquone, carbazilquinone, triaziquone and EO9 have also been used in the clinic for the treatment of cancer. In addition, many other quinone-containing alkylating agents have been tested in preclinical studies and the development of new agents is being actively pursued. This chapter describes the current and past clinical uses of these agents in the treatment of cancer and discusses new agents that are currently in clinical trials. PMID:11056078

  17. Degradable Polymer Composites Fabricated from Starch and Alkyl Cyanoacrylate Monomer

    Science.gov (United States)

    Degradable polymer composites are fabricated from alkyl cyanoacrylate monomer and starch without special equipment. Alkyl cyanoacrylate, which is a major component of “super glue”, is a monomer that polymerizes at room temperature in the presence of initiators. During the fabrication of polymer com...

  18. Toward Efficient Palladium-Catalyzed Allylic C-H Alkylation

    DEFF Research Database (Denmark)

    Jensen, Thomas; Fristrup, Peter

    2009-01-01

    Recent breakthroughs have proved that direct palladium (II)-catalyzed allylic C-H alkylation can be achieved. This new procedure shows that the inherent requirement for a leaving group in the Tsuji-Trost palladium-catalyzed allylic alkylation can be lifted. These initial reports hold great promise...

  19. Thiolated alkyl-modified carbomers: Novel excipients for mucoadhesive emulsions.

    Science.gov (United States)

    Bonengel, Sonja; Hauptstein, Sabine; Leonaviciute, Gintare; Griessinger, Julia; Bernkop-Schnürch, Andreas

    2015-07-30

    The aim of this study was the design and evaluation of mucoadhesive emulsifying polymeric excipients. Three thiol bearing ligands with increasing pKa values of their sulfhydryl group, namely 4-aminothiophenol (pKa=6.86), l-cysteine (pKa=8.4) and d/l-homocysteine (pKa=10.0) were coupled to the polymeric backbone of alkyl-modified carbomer (PA1030). Resulting conjugates displayed 818.5μmol 4-aminothiophenol, 698.5μmol cysteine and 651.5μmol homocysteine per gram polymer and were evaluated regarding the reactivity of thiol groups, emulsifying and mucoadhesive properties. In general, the synthesized conjugates showed a pH dependent reactivity, whereby the fastest oxidation occurred in PA1030-cysteine, as almost no free thiol groups could be detected after 120min. Emulsification of medium chain triglycerides was feasible with all synthesized conjugates leading to oil-in-water-emulsions. Emulsions with PA1030-cysteine displayed the highest stability and the smallest droplet size among the tested formulations. Oxidation and consequently cross-linking of the thiomers prior to the emulsification process led to an overall decreased emulsion stability. Evaluating mucosal residence time of thiomer emulsions on porcine buccal mucosa, a 9.2-fold higher amount of formulation based on PA1030-cysteine remained on the mucosal tissue within 3h compared to the unmodified polymer. According to these results, the highest reactive ligand l-cysteine seems to be most promising in order to obtain thiolated polymers for the preparation of mucoadhesive o/w-emulsions. PMID:25857707

  20. Extra virgin olive oil reduces liver oxidative stress and tissue depletion of long-chain polyunsaturated fatty acids produced by a high saturated fat diet in mice

    Directory of Open Access Journals (Sweden)

    Valenzuela, R.

    2016-06-01

    Full Text Available Long-chain polyunsaturated fatty acids (LCPUFA which are synthesized mainly in the liver have relevant functions in the organism. A diet high in fat (HFD generates an increase in the levels of fat and induces oxidative stress (lipo-peroxidation in the liver, along with a reduction in tissue n-3 and n-6 LCPUFA. Extra virgin olive oil (EVOO is rich in anti-oxidants (polyphenols and tocopherols which help to prevent the development of oxidative stress. This study evaluated the role of EVOO in preventing the induction of fat deposition and oxidative stress in the liver and in the depletion of LCPUFA in the liver, erythrocytes and brain generated by a HFD in C57BL/6J mice. Four experimental groups (n = 10/group were fed a control diet (CD or a HFD for 12 weeks and were respectively supplemented with EVOO (100 mg/day. The group fed HFD showed a significant increase (p Los ácidos grasos poliinsaturados de cadena larga (AGPICL sintetizados principalmente por el hígado, cumplen funciones relevantes en el organismo. Una dieta alta en grasa (DAG genera un incremento en los niveles de grasa y estrés oxidativo (lipoperoxidación en hígado y una reducción en los niveles de AGPICL n-3 y n-6 en diferentes tejidos. El aceite de oliva extra virgen (AOEV es rico en antioxidantes (polifenoles y tocoferoles que ayudan a prevenir el desarrollo del estrés oxidativo. Este trabajo evaluó el rol del AOEV en la prevención del depósito de grasa, estrés oxidativo hepático y reducción de los AGPICL n-3 y n-6 en diferentes tejidos generado por una DAG en ratones C57BL/6J. Cuatro grupos experimentales (n=10/grupo fueron alimentados (12 semanas con dieta control (DC o DAG y suplementados con AOEV (100 mg/día. El grupo alimentado con DAG presentó un incremento (p < 0,05 en la acumulación de grasa y estrés oxidativo hepático, acompañado de una reducción en los niveles de AGPICL n-3 y n-6 en hígado, eritrocitos y cerebro. La suplementación con AOEV logr

  1. Nutritional enrichment of vegetable oils with long-chain n-3 fatty acids through enzymatic interesterification with a new vegetable lipase

    Directory of Open Access Journals (Sweden)

    Sousa, J. S.

    2015-06-01

    Full Text Available The aim of the present work was to produce vegetable oils enriched with long-chain n-3 fatty acids of nutraceutical interest, through an enzyme-catalyzed interesterification with a new lipase, from physic nut (Jatropha curcas L.. The Vegetable Lipase Powder (biocatalyst called VLP, which has never been applied in functional foods, was obtained from the physic nut seed, and efficiently hydrolyzed the 95% of waste fish oil in 24 h. Urea precipitation was used to concentrate polyunsaturated fatty acids (PUFA and was further interesterified with oils of different sources by means of enzymatic catalysis. After the interesterification reaction, which was also catalyzed by the VLP, the PUFA content in coconut oil increased almost ten-fold from 1.8% to 17.7%. In palm oil, the PUFA content increased two-fold from 10.5% to 21.8%, while in olive oil the level of PUFA increased from 8.6% to 21.3%. The mixture of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA (3.7% to 3.9% was incorporated into the triacylglycerol fraction of each of the coconut, palm and olive oils. Through the hydroesterification (hydrolysis followed by interesterification all the interesterified vegetable oils tested presented sufficient EPA and DHA levels to satisfy the levels recommended for intake by human adults in one tablespoon.El objetivo del presente trabajo fue producir aceites vegetales enriquecidos con ácidos grasos n-3 de cadena larga de interés nutraceutico, por interesterificación catalizada mediante una nueva lipasa, una enzima de semilla de Jatropha curcas L. La lipasa vegetal en polvo (biocatalizador llamada VLP, nunca ha sido aplicada en alimentos funcionales, se obtuvo mediante procedimientos físicos con semillas de nueces, e hidrolizó eficientemente el 95% de aceites de residuos de pescado en 24 h. La precipitación con urea se utilizó para concentrar los ácidos grasos poliinsaturados (PUFA que fueron posteriormente interesterificados con aceites de

  2. Synthesis of structured triacylglycerols containing medium-chain and long-chain fatty acids by interesterification with a stereoespecific lipase from Mucor miehei.

    Directory of Open Access Journals (Sweden)

    Nieto, Susana

    1999-06-01

    Full Text Available The preparation of structured triacylglycerols sn-1, sn-3 dilauryl, sn-2 eicosapentaenoyl glycerol and sn-1, sn-3 dilauryl, sn-2 docosahexaenoyl glycerol by enzymatic interesterification under restricted water availability is described. Laurie acid, one of the substrates for interesterification, was obtained by the controlled hydrolysis of coconut oil by a non-specific lipase obtained from Candida cylindracea. The fatty acid was separated from the hydrolysis products by silverresin column chromatography and converted to methyl ester, sn-2 Eicosapentaenoyl glycerol and sn-2 docosahexaenoyl glycerol were prepared by the hydrolysis of fish oil by the sn-1, sn-3 stereospecific immobilized lipase Lipozyme IM-20 obtained from Mucor miehei as described in the accompanying paper. The interesterification was carried out in a water jacketed glass reactor and the triacylglycerol products were separated and recovered through aluminum oxide column chromatography The interesterification procedure described allows to obtain In laboratory scale structured triacylglycerols containing medium-chain fatty acids at the sn-1 and sn-3 positions and long-chain polyunsaturated fatty acid from marine origin at the sn-2 glycerol position.

    Se describe la preparación de triacilgliceroles estructurados sn-1, sn-3 dilauril, sn-2 ecosapentaenoil glicerol y sn-1, sn-3 diiauril, sn-2 docosahexaenoil glicerol por interesterificación enzimática bajo disponibilidad de agua reducida. Acido láurico, uno de los sustratos para la interesterificación, se obtuvo mediante hidrólisis controlada del aceite de coco por una lipasa no-específica obtenida de Candida cylindracea. Los ácidos grasos se separaron de los productos de hidrólisis mediante cromatografía en columna de resina de plata y convertidos en sus esteres metílicos, sn-2 Eicosapentaenoil glicerol y sn-2 docosahexaenoil glicerol se prepararon mediante hidrólisis de aceite de pescado por la sn-1, sn

  3. Bearing fatigue investigation 3

    Science.gov (United States)

    Nahm, A. H.; Bamberger, E. N.; Signer, H. R.

    1982-01-01

    The operating characteristics of large diameter rolling-element bearings in the ultra high speed regimes expected in advanced turbine engines for high performance aircraft were investigated. A high temperature lubricant, DuPont Krytox 143 AC, was evaluated at bearing speeds to 3 million DN. Compared to the results of earlier, similar tests using a MIL-L-23699 (Type II) lubricant, bearings lubricated with the high density Krytox fluid showed significantly higher power requirements. Additionally, short bearing lives were observed when this fluid was used with AISI M50 bearings in an air atmosphere. The primary mode of failure was corrosion initiated surface distress (fatigue) on the raceways. The potential of a case-carburized bearing to sustain a combination of high-tangential and hertzian stresses without experiencing race fracture was also investigated. Limited full scale bearing tests of a 120 mm bore ball bearing at a speed of 25,000 rpm (3 million DN) indicated that a carburized material could sustain spalling fatigue without subsequent propagation to fracture. Planned life tests of the carburized material had to be aborted, however, because of apparent processing-induced material defects.

  4. β-Alkyl Elimination: Fundamental Principles and Some Applications.

    Science.gov (United States)

    O'Reilly, Matthew E; Dutta, Saikat; Veige, Adam S

    2016-07-27

    This review describes organometallic compounds and materials that are capable of mediating a rarely encountered but fundamentally important reaction: β-alkyl elimination at the metal-Cα-Cβ-R moiety, in which an alkyl group attached to the Cβ atom is transferred to the metal or to a coordinated substrate. The objectives of this review are to provide a cohesive fundamental understanding of β-alkyl-elimination reactions and to highlight its applications in olefin polymerization, alkane hydrogenolysis, depolymerization of branched polymers, ring-opening polymerization of cycloalkanes, and other useful organic reactions. To provide a coherent understanding of the β-alkyl elimination reaction, special attention is given to conditions and strategies used to facilitate β-alkyl-elimination/transfer events in metal-catalyzed olefin polymerization, which provide the well-studied examples. PMID:27366938

  5. Arcturus and the Bears

    Science.gov (United States)

    Antonello, E.

    2009-08-01

    Arcturus is the brightest star in Bootes. The ancient Greek name Arktouros means Bear Guard. The star, however, is not close to Ursa Maior (Big She-Bear) and Ursa Minor (Little She-Bear), as the name would suggest. This curious discrepancy could be explained by the star proper motion, assuming the name Bear Guard is a remote cultural heritage. The proper motion analysis could allow us to get an insight also into an ancient myth regarding Ursa Maior. Though we cannot explain scientifically such a myth, some interesting suggestions can be obtained about its possible origin, in the context of the present knowledge of the importance of the cult of the bear both during the Palaeolithic times and for several primitive populations of modern times, as shown by the ethnological studies.

  6. Regioselective Alkylative Carboxylation of Allenamides with Carbon Dioxide and Dialkylzinc Reagents Catalyzed by an N-Heterocyclic Carbene-Copper Complex.

    Science.gov (United States)

    Gholap, Sandeep Suryabhan; Takimoto, Masanori; Hou, Zhaomin

    2016-06-13

    The alkylative carboxylation of allenamide catalyzed by an N-heterocyclic carbene (NHC)-copper(I) complex [(IPr)CuCl] with CO2 and dialkylzinc reagents was investigated. The reaction of allenamides with dialkylzinc reagents (1.5 equiv) and CO2 (1 atm.) proceeded smoothly in the presence of a catalytic quantity of [(IPr)CuCl] to afford (Z)-α,β-dehydro-β-amino acid esters in good yields. The reaction is regioselective, with the alkyl group introduced onto the less hindered γ-carbon, and the carboxyl group introduced onto the β-carbon atom of the allenamides. The first step of the reaction was alkylative zincation of the allenamides to give an alkenylzinc intermediate followed by nucleophilic addition to CO2 . A variety of cyclic and acyclic allenamides were found to be applicable to this transformation. Dialkylzinc reagents bearing β-hydrogen atoms, such as Et2 Zn or Bu2 Zn, also gave the corresponding alkylative carboxylation products without β-hydride elimination. The present methodology provides an easy route to alkyl-substituted α,β-dehydro-β-amino acid ester derivatives under mild reaction conditions with high regio- and stereoselectivtiy. PMID:27167688

  7. Recycling and Activity Recovery of Chloroaluminate Ionic Liquid as Catalyst for Alkylation of Benzene with 1-Dodecene

    Institute of Scientific and Technical Information of China (English)

    乔聪震; 李成岳

    2006-01-01

    Performances of 1-butyl-3-methylimidazolium aluminium chloride ([BMIM]Cl-AlCl3) ionic liquid as catalyst for the alkylation of benzene with long chain olefins were investigated in a continuous operation mode. A small pilot plant with continuous mixing-reacting-separating-recycling functions, equipped with a static mixer reactor, a tube packed with metal Al thread and a combined liquid-liquid settling phase separator, was introduced as an alternative. The results showed that the continuous fast mixing and separation of ionic liquid catalyst from reactant mixture could be synchronously accomplished within a wider flow rate ratio range of the recycling reaction mixture to the ionic liquid catalyst. The recycling of chloroaluminate ionic liquid was realized. ICP-AES detection results of Al content in the reactants proves that in-situ Al compensation to the reaction system may be an important choice to prolong the stable running time of moisture-sensitive ionic liquid [BMIM]Cl-AlCl3 when feedstock inevitably contains trace water. It suggests that the activity of chloroaluminate ionic liquid is recovered under the in-situ Al compensation operation.

  8. Ultra-precision bearings

    CERN Document Server

    Wardle, F

    2015-01-01

    Ultra-precision bearings can achieve extreme accuracy of rotation, making them ideal for use in numerous applications across a variety of fields, including hard disk drives, roundness measuring machines and optical scanners. Ultraprecision Bearings provides a detailed review of the different types of bearing and their properties, as well as an analysis of the factors that influence motion error, stiffness and damping. Following an introduction to basic principles of motion error, each chapter of the book is then devoted to the basic principles and properties of a specific type of bearin

  9. Diastereoselective synthesis of new O-alkylated and C-branched inositols and their corresponding fluoro analogues

    Science.gov (United States)

    Chrétien, Françoise; Chapleur, Yves

    2016-01-01

    Summary Efficient routes were developed for the diastereoselective synthesis of new O-alkylated and C-branched inositols and their corresponding fluoro analogues. The key steps of the synthesis were the easy accessibility of different types of arms in term of configuration (myo and scyllo), the linking method and length, which could modulate the biological properties. These inositol derivatives, bearing an arm terminated either with a hydroxy group or a fluorine atom, could be interesting candidates for diastereoisomeric intermediates and biological evaluations, especially for PET imaging experiments. PMID:26977196

  10. Replacing conventional carbon nucleophiles with electrophiles: nickel-catalyzed reductive alkylation of aryl bromides and chlorides.

    Science.gov (United States)

    Everson, Daniel A; Jones, Brittany A; Weix, Daniel J

    2012-04-11

    A general method is presented for the synthesis of alkylated arenes by the chemoselective combination of two electrophilic carbons. Under the optimized conditions, a variety of aryl and vinyl bromides are reductively coupled with alkyl bromides in high yields. Under similar conditions, activated aryl chlorides can also be coupled with bromoalkanes. The protocols are highly functional-group tolerant (-OH, -NHTs, -OAc, -OTs, -OTf, -COMe, -NHBoc, -NHCbz, -CN, -SO(2)Me), and the reactions are assembled on the benchtop with no special precautions to exclude air or moisture. The reaction displays different chemoselectivity than conventional cross-coupling reactions, such as the Suzuki-Miyaura, Stille, and Hiyama-Denmark reactions. Substrates bearing both an electrophilic and nucleophilic carbon result in selective coupling at the electrophilic carbon (R-X) and no reaction at the nucleophilic carbon (R-[M]) for organoboron (-Bpin), organotin (-SnMe(3)), and organosilicon (-SiMe(2)OH) containing organic halides (X-R-[M]). A Hammett study showed a linear correlation of σ and σ(-) parameters with the relative rate of reaction of substituted aryl bromides with bromoalkanes. The small ρ values for these correlations (1.2-1.7) indicate that oxidative addition of the bromoarene is not the turnover-frequency determining step. The rate of reaction has a positive dependence on the concentration of alkyl bromide and catalyst, no dependence upon the amount of zinc (reducing agent), and an inverse dependence upon aryl halide concentration. These results and studies with an organic reductant (TDAE) argue against the intermediacy of organozinc reagents. PMID:22463689

  11. Organomontmorillonites Modified with 2-Methacryloyloxy Ethyl Alkyl Dimethyl Ammonium Bromide

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-quan; WU Wen-hui

    2007-01-01

    Organomontmorillonites (organo-MMT) were synthesized by means of montmorillonites (MMT) modified with a series of 2-methacryloyloxy ethyl alkyl dimethyl ammonium bromide (MAAB) having different alkyl chain lengths as cationic surfactants through a cationic exchanging reaction, and were characterized by FTIR, TG, elemental analysis, and XRD. The microenvironment of the organic interlayer such as the orientation and arrangement of the alkyl chains of MAAB, as well as the properties of nanocomposite hydrogels, were also investigated. The amount of organic components absorbed on interlayer and the basal spacing of organo-MMT both increase with the increasing of alkyl length of MAAB. When carbon number of alkyl chain is in the region of 8 to 14, the alkyl chains between layers would adopt a disordered gauche conformation; while the carbon number is 16, an ordered all-trans conformation with a vertical orientation would be found together with the disordered gauche conformation according to the results of XRD and FTIR. Due to the difference of microenvironment of organic interlayer, the Young's moduli of the nanocomposite hydrogels increased as the alkyl chains of MAAB became longer.

  12. Management recommendations: Bear River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Bear River Migratory Bird Refuge, by a land use specialist. Recommendations, time frame and additional...

  13. Perturbation and age-related changes in the fatty acid pattern of soleus muscle phospholipids and triglycerides in rats depleted in long-chain polyunsaturated omega3 fatty acids.

    Science.gov (United States)

    Malaisse, Willy J; Portois, Laurence; Sener, Abdullah; Carpentier, Yvon A

    2007-12-01

    Altered D-glucose metabolism prevails in the soleus muscle of rats depleted in long-chain polyunsaturated omega3 fatty acids (omega3). In these animals, the prior intravenous injection of an omega3-rich medium-chain triglyceride:fish oil emulsion (omega3-FO rats), as compared to that of an omega3-poor medium-chain triglyceride:olive oil emulsion (omega3-OO rats), may either correct or aggravate selected metabolic variables. This study deals with the fatty acid pattern of soleus phospholipids and triglycerides in control animals versus omega3-depleted rats not injected with any lipid emulsion (omega3-NI rats) and in omega3-OO versus omega3-FO rats. In each group of omega3-depleted rats, age-related changes were also monitored. The omega3-depleted rats displayed low long-chain polyunsaturated omega3 fatty acid content, facilitated metabolism of long-chain polyunsaturated omega6 fatty acids, and increased Delta9-desaturase activity. Both the age-related changes in lipid variables and those attributable to the prior intravenous injection of the omega3-rich lipid emulsion consisted either in a move towards normalization or in the opposite direction, i.e. towards aggravation of the defect found in the omega3-depleted rats. Emphasis is placed, therefore, on the unusual situation found in the soleus muscle of omega3-depleted rats, in which both lipid and metabolic variables may be either favourably or adversely affected by the same environmental factor(s). PMID:17982700

  14. Simple and Efficient Microwave Assisted N-Alkylation of Isatin

    Directory of Open Access Journals (Sweden)

    María Mercedes Blanco

    2008-04-01

    Full Text Available We present herein the results of microwave promoted N-alkylations of isatin (1with different alkyl, benzyl and functionalized alkyl halides. Reactions were carried outunder different conditions, always employing methodologies compatible with MW assistedchemistry. Generation of isatin anion employing diverse bases and solvents or using thepreformed isatin sodium salt was tested. The best results were achieved using K2CO3 orCs2CO3 and a few drops of N,N-dimethylformamide or N-methyl-2-pyrrolidinone. Thesereactions present noteworthy advantages over those carried out employing conventionalheating.

  15. Impact of Alkyl Spacer Length on Aggregation Pathways in Kinetically Controlled Supramolecular Polymerization.

    Science.gov (United States)

    Ogi, Soichiro; Stepanenko, Vladimir; Thein, Johannes; Würthner, Frank

    2016-01-20

    We have investigated the kinetic and thermodynamic supramolecular polymerizations of a series of amide-functionalized perylene bisimide (PBI) organogelator molecules bearing alkyl spacers of varied lengths (ethylene to pentylene chains, PBI-1-C2 to PBI-1-C5) between the amide and PBI imide groups. These amide-functionalized PBIs form one-dimensional fibrous nanostructures as the thermodynamically favored states in solvents of low polarity. Our in-depth studies revealed, however, that the kinetic behavior of their supramolecular polymerization is dependent on the spacer length. Propylene- and pentylene-tethered PBIs follow a similar polymerization process as previously observed for the ethylene-tethered PBI. Thus, the monomers of these PBIs are kinetically trapped in conformationally restricted states through intramolecular hydrogen bonding between the amide and imide groups. In contrast, the intramolecularly hydrogen-bonded monomers of butylene-tethered PBI spontaneously self-assemble into nanoparticles, which constitute an off-pathway aggregate state with regard to the thermodynamically stable fibrous supramolecular polymers obtained. Thus, for this class of π-conjugated system, an unprecedented off-pathway aggregate with high kinetic stability could be realized for the first time by introducing an alkyl linker of optimum length (C4 chain) between the amide and imide groups. Our current system with an energy landscape of two competing nucleated aggregation pathways is applicable to the kinetic control over the supramolecular polymerization by the seeding approach. PMID:26699283

  16. Gear bearing drive

    Science.gov (United States)

    Weinberg, Brian (Inventor); Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  17. Rolling bearing analysis

    CERN Document Server

    Harris, Tedric A

    2001-01-01

    One of the most well-known experts in the field brings cutting-edge research to practitioners in the new edition of this important reference. Covers the improved mathematical calculations for rolling bearing endurance developed by the American Society of Mechanical Engineers and the Society of Lubrication and Tribology Engineers. Updated with new material on Condition-Based Maintenance, new testing methods, and new bearing materials.

  18. My Little Teddy Bear

    Institute of Scientific and Technical Information of China (English)

    钱佳楠

    2005-01-01

    @@ As Valentine's Day came closer,every shop was full of colourful gifts such as cookies in the shape of heart, chocolates,Teddy Bears and so on.When I step into a shop on February 14th,I felt most lonely as I was alone.With mv eves fixed on a lovely Teddy Bear, I wished that someone could send me this stuffed toy.

  19. Genetic variation in FADS genes is associated with maternal long-chain PUFA status but not with cognitive development of infants in a high fish-eating observational study.

    OpenAIRE

    Yeates, Alison J.; Love, Tanzy M; Engström, Karin; Mulhern, Maria S.; McSorley, Emeir M.; Grzesik, Katherine; Alhamdow, Ayman; Wahlberg, Karin E; Thurston, Sally W.; Davidson, Philip W.; van Wijngaarden, Edwin; Watson, Gene E.; Shamlaye, Conrad F; Myers, G J; Strain., J.J.

    2015-01-01

    Long-chain n-6 and n-3 PUFA (LC-PUFA), arachidonic acid (AA) (20:4n-6) and DHA (22:6n-3), are critical for optimal brain development. These fatty acids can be consumed directly from the diet, or synthesized endogenously from precursor PUFA by Δ-5 (encoded by FADS1) and Δ-6 desaturases (encoded by FADS2). The aim of this study was to determine the potential importance of maternal genetic variability in FADS1 and FADS2 genes to maternal LC-PUFA status and infant neurodevelopment in populations ...

  20. Oil recovery with sulfomethylated poly (lower alkyl vinyl ether/maleic anhydride)

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.J.; Falk, D.O.

    1973-05-22

    Lower alkyl vinyl ether e.g., methyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, hexyl vinyl ether, is copolymerized conventionally with maleic anhydride, the resulting copolymer is treated with ammonia or ammonium hydroxide to form the partial amide-ammonium salt, and this salt is in turn treated with formaldehyde and thereafter or simultaneously with ammonium or alkali metal salt sulfite (including bisulfites, etc.) to form an at least partially sulfomethylated copolymer. Aqueous solutions of the sulfomethylated copolymer are useful in increasing the viscosity of drive fluids used in the supplemented recovery of petroleum from subterranean formations. In general, enhancing the polyionic character of mobility control agents used in supplemented recovery of petroleum provides enhanced recovery. Achieving this enhancement of polyionic character through use of sulfonate groups provides a mobility control agent with good ability to sustain viscosity in the presence of brine and lime, usually present in the connate waters of petroleum-bearing formations. (7 claims)

  1. Detection of Alkylating Agents using Electrical and Mechanical Means

    Energy Technology Data Exchange (ETDEWEB)

    Gerchikov, Yulia; Borzin, Elena; Gannot, Yair; Shemesh, Ariel; Meltzman, Shai; Hertzog-Ronen, Carmit; Eichen, Yoav [Schulich Department of Chemistry, Technion-Israel Institute of Technology, Technion City, 32000, Haifa (Israel) (Israel); Tal, Shay [Present address: Systems Biology Department, Harvard Medical School, Boston, MA 02115 (United States); Stolyarova, Sara; Nemirovsky, Yael; Tessler, Nir, E-mail: chryoav@tx.technion.ac.il [Department of Electrical Engineering, Technion-Israel Institute of Technology, Technion City, 32000, Haifa (Israel)

    2011-08-17

    Alkylating agents are reactive molecules having at least one polar bond between a carbon atom and a good leaving group. These often simple molecules are frequently used in organic synthesis, as sterilizing agents in agriculture and even as anticancer agents in medicine. Unfortunately, for over a century, some of the highly reactive alkylating agents are also being used as blister chemical warfare agents. Being relatively simple to make, the risk is that these will be applied by terrorists as poor people warfare agents. The detection and identification of such alkylating agents is not a simple task because of their high reactivity and simple structure of the reactive site. Here we report on new approaches to the detection and identification of such alkylating agents using electrical (organic field effect transistors) and mechanical (microcantilevers) means.

  2. Detection of Alkylating Agents using Electrical and Mechanical Means

    International Nuclear Information System (INIS)

    Alkylating agents are reactive molecules having at least one polar bond between a carbon atom and a good leaving group. These often simple molecules are frequently used in organic synthesis, as sterilizing agents in agriculture and even as anticancer agents in medicine. Unfortunately, for over a century, some of the highly reactive alkylating agents are also being used as blister chemical warfare agents. Being relatively simple to make, the risk is that these will be applied by terrorists as poor people warfare agents. The detection and identification of such alkylating agents is not a simple task because of their high reactivity and simple structure of the reactive site. Here we report on new approaches to the detection and identification of such alkylating agents using electrical (organic field effect transistors) and mechanical (microcantilevers) means.

  3. Climate Drives Polar Bear Origins

    Science.gov (United States)

    In their provocative analysis of northern bears (“Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage,” Reports, 20 April, p. 344), F. Hailer et al. use independent nuclear loci to show that polar bears originated during the middle Pleistocene, rather than during t...

  4. Copper-catalyzed arylation of alkyl halides with arylaluminum reagents

    Science.gov (United States)

    Shrestha, Bijay

    2015-01-01

    Summary We report a Cu-catalyzed coupling between triarylaluminum reagents and alkyl halides to form arylalkanes. The reaction proceeds in the presence of N,N,N’,N’-tetramethyl-o-phenylenediamine (NN-1) as a ligand in combination with CuI as a catalyst. This catalyst system enables the coupling of primary alkyl iodides and bromides with electron-neutral and electron-rich triarylaluminum reagents and affords the cross-coupled products in good to excellent yields. PMID:26734088

  5. Copper-catalyzed arylation of alkyl halides with arylaluminum reagents

    Directory of Open Access Journals (Sweden)

    Bijay Shrestha

    2015-12-01

    Full Text Available We report a Cu-catalyzed coupling between triarylaluminum reagents and alkyl halides to form arylalkanes. The reaction proceeds in the presence of N,N,N’,N’-tetramethyl-o-phenylenediamine (NN-1 as a ligand in combination with CuI as a catalyst. This catalyst system enables the coupling of primary alkyl iodides and bromides with electron-neutral and electron-rich triarylaluminum reagents and affords the cross-coupled products in good to excellent yields.

  6. Alkyl aryl ethers in lignite solubilization

    Energy Technology Data Exchange (ETDEWEB)

    Mustral, A.M.; Cebolla, V.L.; Gavilan, J.M.

    1985-03-01

    The FT-I.R. and /sup 1/H N.M.R. spectroscopic analyses of oils or maltenes from a Spanish lignite (Utrillas, Teruel), are reported. These oils were obtained by depolymerization with alkyl aromatic ethers (anisole, 3-methyl anisole and 1,3-dimethoxybenzene) catalyzed by Lewis acids ZnCl/sub 2/, AlCl/sub 3/, SbCl/sub 3/ and BF/sub 3/ (as boron trifluoride etherate), at atmospheric pressure and temperatures <220/sup 0/C. Bands due to aromatic ethers in the I.R. and N.M.R. spectra of the oils obtained by depolymerization indicate solvent incorporation. Oils obtained by direct lignite extraction showed 25% aromatic H and some H /sub i/ (approx. = 3%) without OH groups. These appeared in some oils obtained by depolymerization with AlCl/sub 3/ and were due to secondary reactions with the aromatic extract. Oils derived from processes with good yields showed increases in aromaticity. The extent of substitution of aromatic rings in oils obtained by depolymerization was less than for oils directly extracted. All the oils studied show a low degree of condensation.

  7. Alkyl-halogenide promoted ionic liquid catalysis of isobutane/butene-alkylation

    Energy Technology Data Exchange (ETDEWEB)

    Schilder, L.; Korth, W.; Jess, A. [Bayreuth Univ. (Germany). Dept. of Chemical Engineering

    2011-07-01

    The effect of two different types of promoters on the performance of Lewis-acidic chloroaluminate ionic liquid catalysts was studied for liquid liquid biphasic isobutane/2-butene alkylation. In particular, the activity and selectivity of such catalytic systems was investigated. Experimental results obtained from a batch reactor show, that tert-butyl halides increase the reaction rate significantly and shift the C8-selectivity towards the desired high-octane trimethylpentanes (TMPs). But, secondary reactions like oligomerization and cracking are not affected by the use of these promoters. (orig.)

  8. Alcohols as alkylating agents in heteroarene C-H functionalization

    Science.gov (United States)

    Jin, Jian; MacMillan, David W. C.

    2015-09-01

    Redox processes and radical intermediates are found in many biochemical processes, including deoxyribonucleotide synthesis and oxidative DNA damage. One of the core principles underlying DNA biosynthesis is the radical-mediated elimination of H2O to deoxygenate ribonucleotides, an example of `spin-centre shift', during which an alcohol C-O bond is cleaved, resulting in a carbon-centred radical intermediate. Although spin-centre shift is a well-understood biochemical process, it is underused by the synthetic organic chemistry community. We wondered whether it would be possible to take advantage of this naturally occurring process to accomplish mild, non-traditional alkylation reactions using alcohols as radical precursors. Because conventional radical-based alkylation methods require the use of stoichiometric oxidants, increased temperatures or peroxides, a mild protocol using simple and abundant alkylating agents would have considerable use in the synthesis of diversely functionalized pharmacophores. Here we describe the development of a dual catalytic alkylation of heteroarenes, using alcohols as mild alkylating reagents. This method represents the first, to our knowledge, broadly applicable use of unactivated alcohols as latent alkylating reagents, achieved via the successful merger of photoredox and hydrogen atom transfer catalysis. The value of this multi-catalytic protocol has been demonstrated through the late-stage functionalization of the medicinal agents, fasudil and milrinone.

  9. Final Technical Report [Development of Catalytic Alkylation and Fluoroalkylation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Vicic, David A.

    2014-05-01

    In the early stages of this DOE-funded research project, we sought to prepare and study a well-defined nickel-alkyl complex containing tridentate nitrogen donor ligands. We found that reaction of (TMEDA)NiMe2 (1) with terpyridine ligand cleanly led to the formation of (terpyridyl)NiMe (2), which we also determined to be an active alkylation catalyst. The thermal stability of 2 was unlike that seen for any of the active pybox ligands, and enabled a number of key studies on alkyl transfer reactions to be performed, providing new insights into the mechanism of nickel-mediated alkyl-alkyl cross-coupling reactions. In addition to the mechanistic studies, we showed that the terpyridyl nickel compounds can catalytically cross-couple alkyl iodides in yields up to 98% and bromides in yields up to 46 %. The yields for the bromides can be increased up to 67 % when the new palladium catalyst [(tpy’)Pd-Ph]I is used. The best route to the targeted [(tpy)NiBr] (1) was found to involve the comproportionation reaction of [(dme)NiBr{sub 2}] and [Ni(COD){sub 2}] in the presence of two equivalents of terpyridine. This reaction was driven to high yields of product formation (72 % isolated) by the precipitation of 1 from THF solvent.

  10. Active-site-directed reductive alkylation of xanthine oxidase by imidazo[4,5-g]quinazoline-4,9-diones functionalized with a leaving group.

    Science.gov (United States)

    Lee, C H; Skibo, E B

    1987-11-17

    A new class of purine antimetabolites, directed toward xanthine oxidase, was designed by employing some of the features found in the bioreductive alkylator mitomycin C. The design involved functionalizing the purine-like imidazo[4,5-g]quinazoline ring system as a quinone (4,9-dione) bearing a 2 alpha leaving group. Due to the presence of the electron-deficient quinone ring, the leaving group cannot participate in alkylation reactions. Reduction to the hydroquinone (4,9-dihydroxy) derivative, however, permits elimination of the leaving group to afford an alkylating quinone methide. In spite of the electronic differences, both quinone and hydroquinone derivatives of the imidazo[4,5-g]quinazoline system are able to enter the purine-utilizing active site of the enzyme. Thus, the hypoxanthine-like quinone derivative [2-(bromomethyl)-3-methylimidazo[4,5-g]quinazoline-4,8, 9(3H, 7H)-trione] and its hydroquinone derivative can act as reducing substrates for the enzyme, resulting in conversion to the xanthane-like 6-oxo derivatives. Hydrolysis studies described herein indicate that the hypoxanthine-like hydroquinone derivative eliminates HBr to afford an extended quinone methide species. The observed alkylation of the enzyme by this derivative may thus pertain to quinone methide generation and nucleophile trapping during enzymatic oxidation at the 6-position. Enzymatic studies indicate that the hypoxanthine-like quinone is an oxidizing suicide substrate for the enzyme. Thus, the reduced enzyme transfers electrons to this quinone, and the resulting hydroquinone inactivates the enzyme. As with mitomycin C, reduction and quinone methide formation are necessary for alkylation by the title quinone. This system is therefore an example of a purine active-site-directed reductive alkylator.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3427077

  11. Partial tooth gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2010-01-01

    A partial gear bearing including an upper half, comprising peak partial teeth, and a lower, or bottom, half, comprising valley partial teeth. The upper half also has an integrated roller section between each of the peak partial teeth with a radius equal to the gear pitch radius of the radially outwardly extending peak partial teeth. Conversely, the lower half has an integrated roller section between each of the valley half teeth with a radius also equal to the gear pitch radius of the peak partial teeth. The valley partial teeth extend radially inwardly from its roller section. The peak and valley partial teeth are exactly out of phase with each other, as are the roller sections of the upper and lower halves. Essentially, the end roller bearing of the typical gear bearing has been integrated into the normal gear tooth pattern.

  12. Blood Pump Bearing System

    Science.gov (United States)

    Aber, Gregory S. (Inventor)

    2000-01-01

    An apparatus is provided for a blood pump bearing system within a pump housing to support long-term highspeed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the Ir shaft to support big speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  13. Depolymerization of coal by oxidation and alkylation; Sanka bunkai to alkyl ka ni yoru sekitan kaijugo

    Energy Technology Data Exchange (ETDEWEB)

    Tomita, H.; Isoda, T.; Kusakabe, K.; Morooka, S. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hayashi, J. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology

    1996-10-28

    Change in depolymerization degree and coal structure was studied for depolymerization treatment of coal in various alcohol containing aqueous hydrogen peroxide. In experiment, the mixture of Yallourn coal, alcohol and aqueous hydrogen peroxide was agitated in nitrogen atmosphere of normal pressure at 70{degree}C for 12 hours. As the experimental result, the methanol solubility of only 5% of raw coal increased up to 35.2% by hydrogen peroxide treatment, while the yield of insoluble matters also decreased from 94% to 62%. Most of the gas produced during treatment was composed of inorganic gases such as CO and CO2, and its carbon loss was extremely decreased by adding alcohol. From the analytical result of carbon loss in hydrogen peroxide treatment, it was clarified that alkylation advances with introduction of alkyl group derived from alcohol into coal by hydrogen peroxide treatment under a coexistence of alcohol, and depolymerization reaction of coal itself is thus promoted by alcohol. 4 refs., 7 figs., 1 tab.

  14. Modular gear bearings

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2009-01-01

    A gearing system using modular gear bearing components. Each component is composed of a core, one or more modules attached to the core and two or more fastening modules rigidly attaching the modules to the core. The modules, which are attached to the core, may consist of gears, rollers or gear bearing components. The core orientation affects the orientation of the modules attached to the core. This is achieved via the keying arrangement of the core and the component modules that attach to the core. Such an arrangement will also facilitate the phase tuning of gear modules with respect to the core and other gear modules attached to the core.

  15. Development of Flexible Bearing

    Directory of Open Access Journals (Sweden)

    K.S.Mohanraj

    2014-06-01

    Full Text Available Elastomeric base isolation systems are proven to be effective in reducing seismic forces transmitted to buildings. However, due to their cost, the use of these devices is currently limited to large and expensive buildings. A fiber reinforced elastomeric isolator utilizes fiber fabric, such as carbon fiber, glass fibre, and etc. as the reinforcement material instead of solid steel plates. The fibre fabric reinforcement is extensible in tension and has no flexural rigidity. Elastomers normally used in the isolator are natural rubber; neoprene, butyl rubber and nit rile rubber etc. These devices were fabricated by binding alternating layers of rubber and fibre mesh. The fibre mesh is used to increase the vertical stiffness of the bearings while maintaining low lateral stiffness. Characterizing the behaviour of a fibre reinforced bearing “shape factor” of the bearing, Poisson’s ratio of the elastomeric material and flexibility of the reinforcing sheets and investigate the effect of reinforcement flexibility on compressive behaviour of elastomeric bearings with different geometrical and material properties. Bonding with fibre reinforcements can increase the stiffness of elastic layers only when the elastic layer is compressed.

  16. Flexure Bearing Reduces Startup Friction

    Science.gov (United States)

    Clingman, W. Dean

    1991-01-01

    Design concept for ball bearing incorporates small pieces of shim stock, wire spokes like those in bicycle wheels, or other flexing elements to reduce both stiction and friction slope. In flexure bearing, flexing elements placed between outer race of ball bearing and outer ring. Elements flex when ball bearings encounter small frictional-torque "bumps" or even larger ones when bearing balls encounter buildups of grease on inner or outer race. Flexure of elements reduce high friction slopes of "bumps", helping to keep torque between outer ring and inner race low and more nearly constant. Concept intended for bearings in gimbals on laser and/or antenna mirrors.

  17. Solubility of gases in 1-alkyl-3methylimidazolium alkyl sulfate ionic liquids: Experimental determination and modeling

    International Nuclear Information System (INIS)

    Highlights: ► The solubility of CO2, CH4 and C2H6 in [emim][EtSO4] is measured with a magnetic suspension balance. ► New data and literature results have been modeled with a Group Contribution equation of state. ► A specific group definition is required to model data of ionic liquids with a [MeSO4] anion. ► Deviations between model and experiments are lower than 10% in most cases. ► Deviations of 34% are observed in the case of the solubility of ethane in the ionic liquid. -- Abstract: The solubility of different gases (carbon dioxide, methane, ethane, carbon monoxide and hydrogen) in ionic liquids with an alkyl sulfate anion has been modeled with the Group Contribution equation of state developed by Skjold-Jørgensen. New gas solubility measurements have been carried out with a high pressure magnetic suspension balance in order to cover pressure and temperature ranges not considered in previous studies and to obtain more experimental information for the correlation of parameters of the equation of state. New solubility measurements include the solubility of carbon dioxide in 1-ethyl 3-methyl imidazolium ethyl sulfate [emim][EtSO4] at temperatures of 298 K and 348 K and pressures ranging from 0.3 MPa to 6.5 MPa, the solubility of methane in [emim][EtSO4] at a temperature of 293 K and pressures ranging from 0.2 MPa to 10.2 MPa, and the solubility of ethane in [emim][EtSO4] at temperatures of 323 K and 350 K and pressures ranging from 0.2 MPa to 4 MPa. Results show that the Group Contribution equation of state can be used to describe the solubility of gases in alkyl sulfate ionic liquids as well as infinite dilution coefficients of alkanes in the ionic liquids, with average deviations between experiments and calculations ranging from 1% to 10% in the case of mixtures with CO2, CO, CH4 and H2 with the alkyl sulfate ionic liquids to up to 34% in the case of the solubility of ethane in [emim][EtSO4

  18. N-Alkyl-, 1-C-Alkyl-, and 5-C-Alkyl-1,5-dideoxy-1,5-imino-(L)-ribitols as Galactosidase Inhibitors.

    Science.gov (United States)

    Front, Sophie; Gallienne, Estelle; Charollais-Thoenig, Julie; Demotz, Stéphane; Martin, Olivier R

    2016-01-01

    A series of 1,5-dideoxy-1,5-imino-(l)-ribitol (DIR) derivatives carrying alkyl or functionalized alkyl groups were prepared and investigated as glycosidase inhibitors. These compounds were designed as simplified 4-epi-isofagomine (4-epi-IFG) mimics and were expected to behave as selective inhibitors of β-galactosidases. All compounds were indeed found to be highly selective for β-galactosidases versus α-glycosidases, as they generally did not inhibit coffee bean α-galactosidase or other α-glycosidases. Some compounds were also found to be inhibitors of almond β-glucosidase. The N-alkyl DIR derivatives were only modest inhibitors of bovine β-galactosidase, with IC50 values in the 30-700 μM range. Likewise, imino-L-ribitol substituted at the C1 position was found to be a weak inhibitor of this enzyme. In contrast, alkyl substitution at C5 resulted in enhanced β-galactosidase inhibitory activity by a factor of up to 1000, with at least six carbon atoms in the alkyl substituent. Remarkably, the 'pseudo-anomeric' configuration in this series does not appear to play a role. Human lysosomal β-galactosidase from leukocyte lysate was, however, poorly inhibited by all iminoribitol derivatives tested (IC50 values in the 100 μM range), while 4-epi-IFG was a good inhibitor of this enzyme. Two compounds were evaluated as pharmacological chaperones for a GM1-gangliosidosis cell line (R301Q mutation) and were found to enhance the mutant enzyme activity by factors up to 2.7-fold. PMID:26644389

  19. Cross-coupling reaction of alkyl halides with grignard reagents catalyzed by Ni, Pd, or Cu complexes with pi-carbon ligand(s).

    Science.gov (United States)

    Terao, Jun; Kambe, Nobuaki

    2008-11-18

    Transition metal-catalyzed cross-coupling reactions of organic halides and pseudo-halides containing a C-X bond (X = I, Br, Cl, OTf, OTs, etc.) with organometallic reagents are among the most important transformations for carbon-carbon bond formation between a variety of sp, sp(2), and sp(3)-hybridized carbon atoms. In particular, researchers have widely employed Ni- and Pd-catalyzed cross-coupling to synthesize complex organic structures from readily available components. The catalytic cycle of this process comprises oxidative addition, transmetalation, and reductive elimination steps. In these reactions, various organometallic reagents could bear a variety of R groups (alkyl, vinyl, aryl, or allyl), but the coupling partner has been primarily limited to sp and sp(2) carbon compounds: alkynes, alkenes, and arenes. With alkyl coupling partners, these reactions typically run into two problems within the catalytic cycle. First, oxidative addition of alkyl halides to a metal catalyst is generally less efficient than that of aryl or alkenyl compounds. Second, the alkylmetal intermediates formed tend to undergo intramolecular beta-hydrogen elimination. In this Account, we describe our efforts to overcome these problems for Ni and Pd chemistry. We have developed new catalytic systems that do not involve M(0) species but proceed via an anionic complex as the key intermediate. For example, we developed a unique cross-coupling reaction of alkyl halides with organomagnesium or organozinc reagents catalyzed by using a 1,3-butadiene as the additive. This reaction follows a new catalytic pathway: the Ni or Pd catalyst reacts first with R-MgX to form an anionic complex, which then reacts with alkyl halides. Bis-dienes were also effective additives for the Ni-catalyzed cross-coupling reaction of organozinc reagents with alkyl halides. This catalytic system tolerates a wide variety of functional groups, including nitriles, ketones, amides, and esters. In addition, we have extended

  20. Alkyl polycyclic aromatic hydrocarbons emissions in diesel/biodiesel exhaust

    Science.gov (United States)

    Casal, Carina S.; Arbilla, Graciela; Corrêa, Sergio M.

    2014-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are widely studied in environmental matrices, such as air, water, soil and sediment, because of their toxicity, mutagenicity and carcinogenicity. Because of these properties, the environmental agencies of developed countries have listed sixteen PAHs as priority pollutants. Few countries have limits for these compounds for ambient air, but they only limit emissions from stationary and mobile sources and occupational areas. There are several studies to specifically address the 16 priority PAHs and very little for the alkyl PAHs. These compounds are more abundant, more persistent and frequently more toxic than the non-alkylated PAHs, and the toxicity increases with the number of alkyl substitutions on the aromatic ring. In this study, a method was developed for the analysis of PAHs and alkyl PAHs by using a GC-MS and large injection volume injection coupled with program temperature vaporisation, which allows for limits of detection below 1.0 ng μL-1. Several variables were tested, such as the injection volume, injection velocity, injector initial temperature, duration of the solvent split and others. This method was evaluated in samples from particulate matter from the emissions of engines employing standard diesel, commercial diesel and biodiesel B20. Samples were collected on a dynamometer bench for a diesel engine cycle and the results ranged from 0.5 to 96.9 ng mL-1, indicating that diesel/biodiesel makes a significant contribution to the formation of PAHs and alkyl PAHs.

  1. Alkyl substituent effect on density, viscosity and chemical behavior of 1-alkyl-3-methylimidazolium chloride.

    Science.gov (United States)

    Olmo, Lourdes del; Lage-Estebanez, Isabel; López, Rafael; García de la Vega, José M

    2014-09-01

    Molecular structure of the conformers of 1-C n -3-methylimidazolium chloride (n = 1 to 4) ionic liquids has been explored and the relationships with density and viscosity have been studied using COSMO related methodologies. Effects of the number of conformers, ionic character, anion-cation relative positions and the alkyl chain length of the cation on predictions of properties have been analyzed. The quality of the predictions has been tested by comparing with experimental results. Moreover, COSMO polarization charge densities, σ-profiles and σ-potentials of the conformers have been analyzed. Predictions on the chemical behavior based on the values of these properties in the conformers have been used to elucidate the affinity for electrophilic and nucleophilic reagents of ionic liquids. PMID:25149437

  2. Overexpression of human fatty acid transport protein 2/very long chain acyl-CoA synthetase 1 (FATP2/Acsvl1) reveals distinct patterns of trafficking of exogenous fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Melton, Elaina M. [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States); Center for Cardiovascular Sciences, Albany Medical College, Albany, NY (United States); Cerny, Ronald L. [Department of Chemistry, University of Nebraska, Lincoln, NE (United States); DiRusso, Concetta C. [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States); Black, Paul N., E-mail: pblack2@unl.edu [Department of Biochemistry, University of Nebraska, Lincoln, NE (United States)

    2013-11-01

    Highlights: •Roles of FATP2 in fatty acid transport/activation contribute to lipid homeostasis. •Use of 13C- and D-labeled fatty acids provide novel insights into FATP2 function. •FATP2-dependent trafficking of FA into phospholipids results in distinctive profiles. •FATP2 functions in the transport and activation pathways for exogenous fatty acids. -- Abstract: In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4 h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The

  3. 光引发长链正构烷烃多氯代反应机理与动力学%Mechanism and Kinetics of Polychlorination of Long Chain n-Alkanes by Photo-Initiation

    Institute of Scientific and Technical Information of China (English)

    易玲敏; 詹晓力; 陈丰秋

    2004-01-01

    Based on the mechanism analysis of the polychlorination of long chain n-alkanes by photo-initiation,a kinetic model was developed. The model parameters were obtained by the method of non-linear fitting. The influences of luminous intensity and concentration of molecular chlorine on the rate of polychlorination are demonstrated by the model. If the luminous intensity is adequate, the polychlorination rate of n-alkane is only controlled by the flow rate of molecular chlorine in a wide range of temperature, and the changes of temperature and luminous intensity have less effect on the reaction rate. In addition, the predictions of chlorine content of polychlorinated n-alkane calculated with the model agree very well with experimental results.

  4. Candida cloacae长链脂肪酸醇氧化酶基因的克隆与表达%Cloning and Expression of Long-chain Fatty-acid Alcohol Oxidase from Candida cloacae

    Institute of Scientific and Technical Information of China (English)

    葛正龙; AntoniR.SLABAS

    2003-01-01

    The cDNA encoding long-chain fatty-acid alcohol oxidase(FAO) was isolated by using RT-PCR method from Canbdida cloacae grown in a medium containing oleic acid.The cDNA of fatty-acid alcohol oxidase was cloned into expression plasmid pET176b under T7 promoter and then transformed into E.coli BL21/DE3.The molecular weight of the expressed protein was estimated to be approximately 64 kD by SDS-PAGE.The expressed protein had a specific catalytic activity of fatty-acid alcohol oxidase and its activity was 1090±116 U/ml medium.Northern blotting revealed that there was high expression of fao mRNA in Candida cloacae yeast grown in a medium containing oleic acid.

  5. Overexpression of human fatty acid transport protein 2/very long chain acyl-CoA synthetase 1 (FATP2/Acsvl1) reveals distinct patterns of trafficking of exogenous fatty acids

    International Nuclear Information System (INIS)

    Highlights: •Roles of FATP2 in fatty acid transport/activation contribute to lipid homeostasis. •Use of 13C- and D-labeled fatty acids provide novel insights into FATP2 function. •FATP2-dependent trafficking of FA into phospholipids results in distinctive profiles. •FATP2 functions in the transport and activation pathways for exogenous fatty acids. -- Abstract: In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4 h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The

  6. A polymorphic variant in the human electron transfer flavoprotein alpha-chain (alpha-T171) displays decreased thermal stability and is overrepresented in very-long-chain acyl-CoA dehydrogenase-deficient patients with mild childhood presentation

    DEFF Research Database (Denmark)

    Bross, P; Pedersen, P; Nyholm, M;

    1999-01-01

    -deficient patients homozygous for the K304E mutation (MCAD E304), (iii) a group of patients with elevated urinary excretion of ethylmalonic acid (EMA) possibly due to decreased short-chain acyl-CoA dehydrogenase activity, and (iv) in patients with proven deficiency of very-long-chain acyl-CoA dehydrogenase (VLCAD......). No significant overrepresentations or underrepresentations were found in the first two patient groups, suggesting that the polymorphisms studied are not significant susceptibility factors in either the MCAD E304 or the EMA patient group. However, in the VLCAD deficient patients the alpha-T171 variant...... (decreased thermal stability) was significantly overrepresented. Subgrouping of the VLCAD patients into three phenotypic classes (severe childhood, mild childhood, and adult presentation) revealed that the overrepresentation of the alpha-T171 variant was significant only in patients with mild childhood...

  7. Reliability for fluid bearings design

    OpenAIRE

    DIOP, Khadim; CHARKI, Abdérafi; CHAMPMARTIN, Stéphane; AMBARI, Abdelhak

    2013-01-01

    This paper presents a new methodology for evaluating the failure probability of fluid bearings which are sensitive components for the design of machine rotors, mechatronic systems and high precision metrology. The static and dynamic behavior of a fluid bearing depends on several parameters, such as external load, bearing dimensions, supply pressure, quality of the machined surfaces, fluid properties, etc. In this paper, the characteristics of a simple geometry thrust bearing are calculated an...

  8. Reliability of a hydrostatic bearing

    OpenAIRE

    CHARKI, Abderafi; DIOP, Khadim; CHAMPMARTIN, Stéphane; AMBARI, Abdelhak

    2013-01-01

    This paper presents a methodology for evaluating the failure probability of fluid bearings, which are sensitive components for the design of machine rotors, mechatronic systems, and high precision metrology. The static and dynamic behavior of a fluid bearing depends on several parameters, such as external load, bearing dimensions, supply pressure, quality of the machined surfaces, fluid properties, etc. In this paper, the characteristics of a simple geometry hydrostatic bearing are calculated...

  9. Households' Interest-bearing Assets

    OpenAIRE

    Ellis Connolly; Fiona Fleming; Jarkko Jääskelä

    2012-01-01

    Households invest around two-fifths of their financial assets in interest-bearing assets. These assets are predominantly held directly in deposits and also via superannuation and other investment funds. Deposits have grown strongly in recent years, although there has been no growth in interest-bearing securities. Compared with other advanced economies, interest-bearing assets represent a relatively small share of financial assets. For the household sector as a whole, interest-bearing assets a...

  10. Alkylation of imidazole under ultrasound irradiation over alkaline carbons

    International Nuclear Information System (INIS)

    N-Alkyl-imidazole has been synthesized by sonochemical irradiation of imidazole and 1-bromobutane using alkaline-promoted carbons (exchanged with the binary combinations of Na, K and Cs). The catalysts were characterized by X-ray photoelectron spectroscopy, thermal analysis and N2 adsorption isotherms. Under the experimental conditions, N-alkyl-imidazoles can be prepared with a high activity and selectivity. It is observed that imidazole conversion increases in parallel with increasing the basicity of the catalyst. The influence of the alkaline promoter, the reaction temperature, and the amount of catalyst on the catalytic activity has been studied. For comparison, the alkylation of imidazole has also been performed in a batch reactor system under thermal activation

  11. Alkyl Radicals as Hydrogen Bond Acceptors: Computational Evidence

    DEFF Research Database (Denmark)

    Hammerum, Steen

    2009-01-01

    Spectroscopic, energetic and structural information obtained by DFT and G3-type computational studies demonstrates that charged proton donors can form moderately strong hydrogen bonds to simple alkyl radicals. The presence of these bonds stabilizes the adducts and modifies their structure, and...... gives rise to pronounced shifts of IR stretching frequencies and to increased absorption intensities. The hydrogen bond acceptor properties of alkyl radicals equal those of many conventional acceptors, e.g., the bond length changes and IR red-shifts suggest that tert-butyl radicals are slightly better...... acceptors than formaldehyde molecules, while propyl radicals are as good as H2O. The hydrogen bond strength appears to depend on the proton affinity of the proton donor and on the ionization energy of the acceptor alkyl radical, not on the donor-acceptor proton affinity difference, reflecting that the...

  12. Alkylation of imidazole under ultrasound irradiation over alkaline carbons

    Energy Technology Data Exchange (ETDEWEB)

    Costarrosa, L. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Calvino-Casilda, V. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Ferrera-Escudero, S. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain); Duran-Valle, C.J. [Dpto. de Quimica Inorganica, Facultad de Ciencias, Universidad de Extremadura, Avenida de Elvas s/n, 06071 Badajoz (Spain); Martin-Aranda, R.M. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9, E-28040 Madrid (Spain)]. E-mail: rmartin@ccia.uned.es

    2006-06-30

    N-Alkyl-imidazole has been synthesized by sonochemical irradiation of imidazole and 1-bromobutane using alkaline-promoted carbons (exchanged with the binary combinations of Na, K and Cs). The catalysts were characterized by X-ray photoelectron spectroscopy, thermal analysis and N{sub 2} adsorption isotherms. Under the experimental conditions, N-alkyl-imidazoles can be prepared with a high activity and selectivity. It is observed that imidazole conversion increases in parallel with increasing the basicity of the catalyst. The influence of the alkaline promoter, the reaction temperature, and the amount of catalyst on the catalytic activity has been studied. For comparison, the alkylation of imidazole has also been performed in a batch reactor system under thermal activation.

  13. Safety Assessment of Alkyl Ethylhexanoates as Used in Cosmetics.

    Science.gov (United States)

    Fiume, Monice; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2015-01-01

    The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) assessed the safety of 16 alkyl ethylhexanoates for use in cosmetics, concluding that these ingredients are safe in cosmetic formulations in the present practices of use and concentrations when formulated to be nonirritating. The alkyl ethylhexanoates primarily function as skin-conditioning agents in cosmetics. The highest concentration of use reported for any of the alkyl ethylhexanoates is 77.3% cetyl ethylhexanoate in rinse-off formulations used near the eye, and the highest leave-on use reported is 52% cetyl ethylhexanoate in lipstick formulations. The Panel reviewed available animal and clinical data related to these ingredients, and the similarities in structure, properties, functions, and uses of ingredients from previous CIR assessments on constituent alcohols that allowed for extrapolation of the available toxicological data to assess the safety of the entire group. PMID:26684798

  14. Structural features of a series of S-alkylated and non-S-alkylated aminothiolate nickel(II) complexes

    Science.gov (United States)

    Chohan, B. S.

    2014-12-01

    The structural aspects of a family of S-alkylated complexes, generated by reacting iodoacetamide or iodoethanol with two mononuclear Ni(II) diaminodithiolate complexes are discussed. The S-alkylation reactions were investigated with particular attention paid to the size of the chelate ring that straps the N,N'-methylamine donors. In one complex the N-methyl groups are cis to each other and in the other they are trans. Both complexes undergo S-alkylation with two equivalents of either reagent, that coordinates through the pendant oxygen to the Ni(II), forming dications with an N2S2O2 ligand donor set. Crystal structures of [NiC12H26N4O2S2]I2 · MeOH, [NiC12H28N2O2S2]I2, and [NiC13H30N2O2S2]I2 · 1/2 MeOH, are determined by single crystal X-ray analysis. The N-methyl groups in each of the alkylated derivatives are trans to each other, suggesting that the cis configuration is highly unfavored for such complexes in octahedral conformation. Crystal packing data shows that each of the alkylated complexes interacts closely with the iodide counterions, and with solvent if present; some of these interactions include H-bonds. Only the iodoacetamide derivative shows any significant interaction with a neighboring molecule.

  15. SYNTHESIS OF 1-n-ALKYL-3-METHYL- AND 1-n-ALKYL-3- PHENYL-5-PYRAZOLONES AND FORMYL DERIVATIVES

    Directory of Open Access Journals (Sweden)

    J. BELMAR

    2001-12-01

    Full Text Available 3-Methyl- and 3-phenyl-5-pyrazolones were alkylated and formylated. The phenyl derivative was less reactive towards alkylation. However in the formylation step 1-n-alkyl-3-methyl- and 1-n-alkyl-3-phenyl-5-pyrazolones showed no difference in reactivity. The alkylated products exist as 5-pyrazolones in chloroform solutions and in dimethylsulfoxide their structure is a 5-hydroxy-pyrazole. Chloroform and dimethyl sulfoxide solutions of 4-formyl derivatives have a structure that is better described as 4-hydroxymethylene-5-pyrazoloneSe alquiló y formiló 3-metil- y 3-fenil-5-pirazolona. El 3-fenil derivado es menos reactivo en la etapa de alquilación. En la etapa de formilación no hay diferencias entre 1-n-alquil-3-metil- o 1-n-alquil-3-fenil-5-pirazolona. Los productos de alquilación presentan una estructura de 5-pirazolona en cloformo, mientras que en dimetilsulfóxido la estructura es del tipo 5-hidroxipirazol. En estos mismos solventes, los derivados formilados solo presentan una estructura que es descrita como 4-hidroximetilén-5-pirazolona

  16. Centrifugally decoupling touchdown bearings

    Science.gov (United States)

    Post, Richard F

    2014-06-24

    Centrifugally decoupling mechanical bearing systems provide thin tensioned metallic ribbons contained in a support structure. This assembly rotates around a stationary shaft being centered at low speeds by the action of the metal ribbons. Tension springs are connected on one end to the ribbons and on the other end to the support structure. The ribbons pass through slots in the inner ring of the support structure. The spring preloading thus insures contact (or near-contact) between the ribbons and the shaft at rotation speeds below the transition speed. Above this speed, however, the centrifugal force on the ribbons produces a tensile force on them that exceeds the spring tensile force so that the ribbons curve outward, effectively decoupling them from mechanical contact with the shaft. They still remain, however, in position to act as a touchdown bearing in case of abnormally high transverse accelerations.

  17. Government Risk-Bearing

    CERN Document Server

    1993-01-01

    The u.s. government bulks large in the nation's financial markets. The huge volume of government-issued and -sponsored debt affects the pricing and volume ofprivate debt and, consequently, resource allocation between competing alternatives. What is often not fully appreciated is the substantial influence the federal government wields overresource allocation through its provisionofcreditandrisk-bearing services to the private economy. Because peopleand firms generally seekto avoid risk, atsomeprice they are willing to pay another party to assume the risk they would otherwise face. Insurance companies are a class of private-sector firms one commonly thinks of as providing these services. As the federal government has expanded its presence in the U.S. economy during this century, it has increasingly developed programs aimed at bearing risks that the private sector either would not take on at any price, or would take on but atapricethoughtto besogreatthatmostpotentialbeneficiarieswouldnotpurchase the coverage. To...

  18. Rotating plug bearing and seal

    Science.gov (United States)

    Wade, Elman E.

    1977-01-01

    A bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing.

  19. Rotating plug bearing and seal

    International Nuclear Information System (INIS)

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  20. ANSWER: A bear paw.

    OpenAIRE

    Ian BICKLE

    2012-01-01

    (Refer to page 186)Answer: Bear Paw sign of Xanthogranulomatous PyelonephritisThe contrast enhanced (portal venous phase)CT of the abdomen showed a global enlargement of the right kidney. There are multiplelow attenuation areas in the renal parenchyma, in a ‘hydronephrotic type manner’, but with no true hydronephrosis. This is due to a renal calculus lying in a contracted pelvis with dilated calyces that contain inflammatory debris. A rim of normal renal tissue enhancesperipherally. The appea...