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Sample records for 1-pentanol 2-pentanol 3-pentanol

  1. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis

    PubMed Central

    Song, Geun C.; Choi, Hye K.; Ryu, Choong-Min

    2015-01-01

    3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen. PMID:26500665

  2. Enthalpies of formation for water + sodium dodecyl sulfate + 1-pentanol + triethanolamine mixtures

    NASA Astrophysics Data System (ADS)

    Batov, D. V.

    2015-05-01

    The enthalpies of mixing of water (H2O) + sodium dodecyl sulfate (NaDDS) + 1-pentanol (PeOH) + triethanolamine (TEA) mixtures with different compositions at 298.15 K are determined using the thermochemical cycle. The enthalpies of dissolution of NaDDS, H2O, PeOH, TEA, and H2O + TEA + PeOH + NaDDS mixtures in 2-propanol are measured by means of calorimetry. The formation of the studied mixtures from neat components is shown to be mainly an exothermic process. The influence of the nature of components and a mixture's composition on the enthalpies of mixing is discussed.

  3. Isothermal vapor-liquid equilibria for 2-methyl-2-butanol + 2-methyl-1-butanol + 1-pentanol

    SciTech Connect

    Aucejo, A.; Burguet, M.C.; Monton, J.B.; Munoz, R.; Sanchotello, M.; Vazquez, M.I. . Dept. de Ingenieria Quimica)

    1994-07-01

    Vapor-liquid equilibria (VLE) for 2-methyl-2-butanol + 2-methyl-1-butanol and 2-methyl-2-butanol + 2-methyl-1-butanol + 1-pentanol have been measured at 373.15 K. The binary VLE results have been correlated by different liquid-phase activity coefficient models. The binary interaction parameters obtained from Wilson, NRTL, and UNIQUAC models in this and a previously study are used to predict the VLE data for the ternary system. Vapor-liquid equilibrium (VLE) data are necessary for the design of distillation processes.

  4. Isothermal vapor-liquid equilibria of 1-pentanol with 2-methyl-1-butanol, 2-methyl-2-butanol, and 3-methyl-2-butanol

    SciTech Connect

    Aucejo, A.; Burguet, M.C.; Monton, J.B.; Munoz, R.; Sanchotello, M.; Vazquez, M.I. . Dept. de Ingenieria Quimica)

    1994-07-01

    The separation of liquid mixtures through distillation is one of the most common operations in chemical industry, and the efficient design of distillation equipment requires a quantitative knowledge of vapor-liquid equilibria (VLE). Vapor-liquid equilibria were measured for binary systems of 1-pentanol + 2-methyl-1-butanol, + 2-methyl-2-butanol, and + 3-methyl-2-butanol at 373.15 K. The results are thermodynamically consistent according to the point-to-point consistency test, and deviation from ideal behavior is small in all cases.

  5. Preparation of zeolite supported TiO2, ZnO and ZrO2 and the study on their catalytic activity in NOx reduction and 1-pentanol dehydration

    NASA Astrophysics Data System (ADS)

    Fatimah, Is

    2016-03-01

    Preparation of zeolite supported TiO2, ZnO and ZrO2 and their catalytic activity was studied. Activated natural zeolite from Indonesia was utilized for the preparation and catalytic activity test on NOx reduction by NH3 and also 1-pentanol dehydration were examined. Physicochemical characterization of materials was studied by x-ray diffraction (XRD) measurement, scanning electron microscope, solid acidity determination and also gas sorption analysis. The results confirmed that the preparation gives some improvements on physicochemical characters suitable for catalysis mechanism in those reactions. Solid acidity and specific surface area contributed significantly to the activity.

  6. Isobaric vapor-liquid equilibria of 1-butanol + N,N-dimethylformamide and 1-pentanol + N,N-dimethylformamide systems at 50.00 and 100.00 kPa

    SciTech Connect

    Marzal, P.; Gabaldon, C.; Seco, A.; Monton, J.B.

    1995-05-01

    The experimental determinations of vapor-liquid equilibria (VLE) are indispensable for the design of separation processes such as distillation columns, extractive distillation, and selection of solvents. Isobaric vapor-liquid equilibria were obtained for the 1-butanol + N,N-dimethylformamide and 1-pentanol + N,N-dimethylformamide systems at 50.00 and 100.00 kPa. The activity coefficients were found to be thermodynamically consistent. The data were correlated with five liquid phase activity coefficient models (Margules, Van Laar, Wilson, NRTL, and UNIQUAC). Experimental vapor pressures of N,N-dimethylformamide are also included.

  7. Surface behavior of amphiphiles in aqueous solution: a comparison between different pentanol isomers.

    PubMed

    Walz, M-M; Caleman, C; Werner, J; Ekholm, V; Lundberg, D; Prisle, N L; Öhrwall, G; Björneholm, O

    2015-06-01

    Position isomerism is ubiquitous in atmospheric oxidation reactions. Therefore, we have compared surface-active oxygenated amphiphilic isomers (1- and 3-pentanol) at the aqueous surface with surface- and chemically sensitive X-ray photoelectron spectroscopy (XPS), which reveals information about the surface structure on a molecular level. The experimental data are complemented with molecular dynamics (MD) simulations. A concentration-dependent orientation and solvation of the amphiphiles at the aqueous surface is observed. At bulk concentrations as low as around 100 mM, a monolayer starts to form for both isomers, with the hydroxyl groups pointing towards the bulk water and the alkyl chains pointing towards the vacuum. The monolayer (ML) packing density of 3-pentanol is approx. 70% of the one observed for 1-pentanol, with a molar surface concentration that is approx. 90 times higher than the bulk concentration for both molecules. The molecular area at ML coverage (≈100 mM) was calculated to be around 32 ± 2 Å(2) per molecule for 1-pentanol and around 46 ± 2 Å(2) per molecule for 3-pentanol, which results in a higher surface concentration (molecules per cm(2)) for the linear isomer. In general we conclude therefore that isomers - with comparable surface activities - that have smaller molecular areas will be more abundant at the interface in comparison to isomers with larger molecular areas, which might be of crucial importance for the understanding of key properties of aerosols, such as evaporation and uptake capabilities as well as their reactivity. PMID:25953683

  8. Composition and Process for Retarding the Premature Aging of PMR Monomer Solutions and PMR Prepegs

    NASA Technical Reports Server (NTRS)

    Alston, William B. (Inventor); Gahn, Gloria S. (Inventor)

    2000-01-01

    Polyimides are derived from solutions of at least one low-boiling organic solvent, e.g. isopropanol containing a mixture of polyimide-forming monomers. The monomeric solutions have an extended shelf life at ambient (room) temperatures as high as 80 C, and consist essentially of a mixture of monoalkyl ester-acids, alkyl diester-diacids and aromatic polyamines wherein the alkyl radicals of the esteracids are derived from lower molecular weight aliphatic secondary alcohols having 3 to 5 carbon atoms per molecule such as isopropanol, secondary butanol, 2-methyl-3-butanol, 2 pentanol or 3-pentanol. The solutions of the polyimide-forming monomers have a substantially improved shelf-life and are particularly useful in the aerospace and aeronautical industry for the preparation of polyimide reinforced fiber composites such as the polyimide cured carbon composites used in jet engines, missiles, and for other high temperature applications.

  9. Experimental neurotoxicity and urinary metabolites of the C5-C7 aliphatic hydrocarbons used as glue solvents in shoe manufacture

    SciTech Connect

    Frontali, N.; Amantini, M.C.; Spagnolo, A.; Guarcini, A.M.; Saltari, M.C.; Brugnone, F.; Perbellini, L.

    1981-12-01

    Rats were intermittently exposed (9 to 10 h/d, 5 to 6 d/week) to controlled concentrations of single analytical grad solvents in ambient air. After periods ranging from 7 to 30 weeks the animals were perfused with glutaraldehyde and samples of nerves were processed for light microscopy of sections and of teased fibers. Animals treated with n-hexane at 5000 ppm (14 weeks) or 2500 ppm (30 weeks) developed the typical giant axonal degeneration already described in rats treated continuously with 400 to 600 ppm of the same solvent for 7 weeks or more. No such alterations were found in rats subjected to the following intermittent respiratory treatments: n-hexane 500 ppm (30 weeks) or 1500 ppm (14 weeks), cyclohexane 1500 or 2500 (30 weeks), n-pentane 3000 ppm (30 weeks), n-heptane 1500 ppm (30 weeks), 2-methylpentane 1500 ppm (14 weeks), and 3-methylpentane 1500 ppm (14 weeks). The following metabolites were found in the urine of rats according to treatment (in parenthesis): 2-methyl-2-pentanol (2-methylpentane); 3-methyl-2-pentanol and 3-methyl-3-pentanol (3-methylpentane), 2-hexanol, 3-hexanol, gamma-valerolactone, 2,5-dimethylfuran, and 2,5-hexanedione (n-hexane). 2-Hexanol was found to be the main urinary metabolite of n-hexane, while 2,5-hexanedione was present only in a lesser proportion. This feature of rat metabolism suggests that in this species 2,5-hexanedione reaches an effective level at its site of action during intermittent respiratory treatment with n-hexane with difficulty and explains the high concentrations necessary to cause polyneuropathy in rats subjected to this treatment.

  10. Effect of Surfactant Supplying with Refrigerant Vapor on Absorption Enhancement

    NASA Astrophysics Data System (ADS)

    Gao, Hongtao; Matsuzaki, Tetsuya; Wang, Jianfeng; Hihara, Eiji

    For the absorption of water vapor into the aqueous lithium bromide solution, eight-carbon alcohol additives such as 2-ethyl-1-hexanolhave been commonly used to improve the absorption process. However, as additives six-carbon and seven-carbon alcohols were not been tested experimentally very much. In present study, absorption of water vapor into the 62 wt% LiBr solution with several six-carbon and seven carbon alcohol additives such as 4-methyl-2-pentanol, 2-ethyl-1-butanol, 1-hexanol, 2 , 4-dimethyl-3-pentanol, 4-heptanol, 2-heptanol and 1-heptanol were investigated by using a simple stagnant pool absorber. Besides using the conventional method which mixing additive into LiBr solution, vapor phase adding method was experimented. Surface tensions of aqueous LiBr solution with different surfactant also were measured by Welhelmy plate method. Absorption of water vapor into the LiBr solution with 2-ethyl-1-hexanol and 1-heptanol were also experimented in falling film absorber by vapor phase adding method. The result showed that the lower the surface tension of LiBr aqueous solution with an additive, the better the effect of absorption enhancement by the corresponding additive, and vapor phase adding method is effective for the absorption of water vapor into the LiBr aqueous solution.

  11. An investigation of bubble coalescence and post-rupture oscillation in non-ionic surfactant solutions using high-speed cinematography.

    PubMed

    Bournival, G; Ata, S; Karakashev, S I; Jameson, G J

    2014-01-15

    Most processes involving bubbling in a liquid require small bubbles to maximise mass/energy transfer. A common method to prevent bubbles from coalescing is by the addition of surfactants. In order to get an insight into the coalescence process, capillary bubbles were observed using a high speed cinematography. Experiments were performed in solutions of 1-pentanol, 4-methyl-2-pentanol, tri(propylene glycol) methyl ether, and poly(propylene glycol) for which information such as the coalescence time and the deformation of the resultant bubble upon coalescence was extracted. It is shown in this study that the coalescence time increases with surfactant concentration until the appearance of a plateau. The increase in coalescence time with surfactant concentration could not be attributed only to surface elasticity. The oscillation of the resultant bubble was characterised by the damping of the oscillation. The results suggested that a minimum elasticity is required to achieve an increased damping and considerable diffusion has a detrimental effect on the dynamic response of the bubble, thereby reducing the damping. PMID:24231084

  12. [Metabolism and toxicity of n-pentane and isopentane].

    PubMed

    Chiba, S; Oshida, S

    1991-04-01

    n-Pentane and isopentane have a wide range of use, for example, for cleaning precision machinery, extracting essence and oil, and as liquid fuel for now very popular disposable lighters. They are contained in liquefied petroleum gas and natural gas as trace constituents. In our present experiments, we studied the metabolism and toxicity of these n-pentane and isopentane metabolites. Male mice of ICR strain were exposed to about 5% n-pentane for one hour while the oxygen in the environmental air was maintained at about 20%. Then their blood and liver tissue were collected and analyzed by means of GC and GC-MS. The metabolites thus obtained were 2-pentanol, 3-pentanol and 2-pentanone. The same procedure was repeated with isopentane; 3-methyl-2-butanol, 2-methyl-2-butanol and 3-methyl-2-butanone were detected as the resultant metabolites. In the presence of the NADPH-generating system liver microsomes were made to react to the substrate of saturated n-pentane or isopentane aqueous solution at 37 degrees C for one hour. As a result, the same metabolites were produced as obtained in the exposure experiment. It was therefore suggested that n-pentane and isopentane were metabolized chiefly by liver microsomes. Male mice of ICR strain were fed with 80 mg/kg b.w. of phenobarbital for consecutive four days and exposed to n-pentane or isopentane for one hour. This resulted in an increase in the amount of 2-pentanol and 2-pentanone in the n-pentane inhalation and 2-methyl-2-butanol in the isopentane inhalation experiment. The toxicity of each metabolite was studied on cultured cells. The metabolites were individually mixed with HeLa S3 cell suspension, incubated for three days, and their concentration which inhibited the growth of cells by 50% (IGC 50) were compared. It was demonstrated as a result that the IGC 50 for any of the metabolites was lower than that for methanol, ethanol or acetone used as control. PMID:1920919

  13. Relative contribution of oxygenated hydrocarbons to the total biogenic VOC emissions of selected mid-European agricultural and natural plant species

    NASA Astrophysics Data System (ADS)

    König, Georg; Brunda, Monika; Puxbaum, Hans; Hewitt, C. Nicholas; Duckham, S. Craig; Rudolph, Jochen

    Emission rates of more than 50 individual VOCs were determined for eight plant species and three different types of grass land typical for natural deciduous and agricultural vegetation in Austria. In addition to the emissions of isoprene and monoterpenes, 33 biogenic oxygenated volatile organic compounds (BOVOCs) were detected. Of these, 2-methyl-l-propanol, 1-butanal, 2-butanal, 1-pentanol, 3-pentanol, 1-hexanol, 6-methyl-5-hepten-2-one, butanal and ethylhexylacetate were observed for the first time as plant emissions. In terms of prevalence of one of the groups of emitted VOCs (isoprene, terpenes, BOVOCs) the grain plants wheat and rye, grape, oilseed rape and the decidous trees hombeam and birch could be classified as "BOVOC"-emitters. For the grass plots examined, BOVOCs and terpenes appear to be of equal importance. The emission rates of the total assigned organic plant emissions ranged from 0.01 μ g -1 h -1 for wheat to 0.8 μg g -1 h -1 for oak (based on dry leaf weight). Intercomparison with available data from other studies show that our emission rates are rather at the lower end of reported ranges. The influence of the stage of growth was examined for rye, rape (comparing emissions of blossoming and nonblossoming plants) and for grape (with and without fruit). Emission rate differences for different stages of growth varied from nondetectable for blossoming and nonblossoming rye to a factor of six for the grape with fruits vs grape without fruits (emission rate based on dry leaf weight). The major decidous tree in Austria (beech) is a terpene emitter, with the contribution of BOVOCs below 5% of the total assigned emissions of 0.2 μg g -1 h -1 for the investigations of 20°C.

  14. New methodology for simultaneous volumetric and calorimetric measurements: Direct determination of {alpha}{sub p} and C{sub p} for liquids under pressure

    SciTech Connect

    Casas, L. M.

    2009-12-15

    A new batch cell has been developed to measure simultaneously both isobaric thermal expansion and isobaric heat capacity from calorimetric measurements. The isobaric thermal expansion is directly proportional to the linear displacement of an inner flexible below and the heat capacity is calculated from the calorimetric signal. The apparatus used was a commercial Setaram C-80 calorimeter and together with this type of vessels can be operated up to 20 MPa and in the temperature range of 303.15-523.15 K, In this work, calibration was carried out using 1-hexanol and subsequently both thermophysical properties were determined for 3-pentanol, 3-ethyl-3-pentanol, and 1-octanol at atmospheric pressure, 5 and 10 MPa, and from 303.15 to 423.15 K in temperature. Finally experimental values were compared with the literature in order to validate this new methodology, which allows a very accurate determination of isobaric thermal expansion and isobaric heat capacity.

  15. A rhodamine-deoxylactam based sensor for chromo-fluorogenic detection of nerve agent simulant.

    PubMed

    Wu, Zhisheng; Wu, Xuanjun; Yang, Yuhui; Wen, Ting-bin; Han, Shoufa

    2012-10-15

    N-(rhodamine B)-deoxylactam-5-amino-1-pentanol (dRB-APOH) was designed and prepared as the chromo-fluorogenic sensor for detection of a nerve agent simulant via analyte triggered tandem phosphorylation and opening of the intramolecular deoxylactam. The successful detection of diethyl chlorophosphate suggests the utility of rhodamine-deoxylactams as the chromo-fluorogenic signal reporting platform for design of sensors targeting reactive chemical species via various chemistries. PMID:22995618

  16. Mechanistic studies of the pathways leading to ethers via coupling of alcohols

    SciTech Connect

    Sun, Qun; Lietti, L.; Herman, R.G.

    1995-12-01

    The reaction mechanisms for the solid acid-catalyzed dehydrative coupling of methanol and ethanol with isobutanol and 2-pentanol to form ethers were examined by using isotope labelling and chiral inversion experiments. When the reactions were carried out at 110{degrees}C and 1 MPa with Et{sup 18}OH and {sup 16}O-isobutanol over Amberlyst-35, 95% of the major product ethyl isobutyl ether (EIBE) contained {sup 16}O, while 96% of the minor product ethyl tertiarybutyl ether (ETBE) contained {sup 18}O. Similar results were obtained with methanol and isobutanol over Nafion-H and Amberlyst-35 catalysts, with MIBE and MTBE as the products. These results indicate that EIBE (MIBE) was produced by a surface-catalyzed S{sub N}2 reaction, while the ETBE (MTBE) product arose via a carbenium intermediate. The analogous reactions carried out over Nafion-H and H-ZSM-5 catalysts with chiral 2-pentanol verified the surface-mediated S{sub N}2 reaction, where in chiral inversion of the product ether was observed relative to the S- and R-2-pentanol reactants. In addition, a remarkable shape selectivity with chiral inversion was observed over the H-ZSM-5 zeolite to selectively form 2-ethoxypentane but not 3-ethoxypentane.

  17. Behavioral and electrophysiological responses of Aedes albopictus to certain acids and alcohols present in human skin emanations.

    PubMed

    Guha, Lopamudra; Seenivasagan, T; Iqbal, S Thanvir; Agrawal, O P; Parashar, B D

    2014-10-01

    Human skin emanations attract hungry female mosquitoes toward their host for blood feeding. In this study, we report the flight orientation and electroantennogram response of Aedes albopictus females to certain unsaturated acids and alcohols found in human skin. In the Y-tube olfactometer, odors of lactic acid and 2-methyl-3-pentanol attracted 54-65% of Ae. albopictus females at all doses in a dose-dependent manner. However, at the highest dose (10(-2) g), the acids repelled 40-45% females. Attractancy (ca. 62-68%) at lower doses and repellency (ca. 30-45%) at higher doses were recorded for 3-methyl-3-pentanol and 1-octen-3-ol, while 5-hexen-1-ol, cis-2-hexen-1-ol, and trans 2-hexen-1-ol odor repelled ca. 55-65% of Ae. albopictus females at all doses. Antenna of female Ae. albopictus exhibited a dose-dependent EAG response up to 10(-3) g of L-lactic acid, trans-2-methyl-2-pentenoic acid, 2-octenoic acid, trans-2-hexen-1-ol and 1-octen-3-ol stimulations; however, the highest dose (10(-2) g) caused a little decline in the EAG response. EAG response of 9-10-fold was elicited by lactic acid, 2-octenoic acid, trans-2-hexenoic acid, and 3-methyl-3-pentanol, while cis-2-hexen-1-ol and trans-2-methyl pentenoic acid elicited 1-5-fold responses compared to solvent control. A blend of attractive compounds could be utilized in odor-baited trap for surveillance and repellent molecules with suitable formulation could be used to reduce the biting menace of mosquitoes. PMID:25049052

  18. Synergic effects in the extraction of paracetamol from aqueous NaCl solution by the binary mixtures of diethyl ether and low molecular weight primary alcohols

    NASA Astrophysics Data System (ADS)

    Nikolić, G. M.; Živković, J. V.; Atanasković, D. S.; Nikolić, M. G.

    2013-12-01

    Liquid-liquid extraction of paracetamol from aqueous NaCl solutions was performed with diethyl ether, 1-propanol, 1-butanol, isobutanol, 1-pentanol, and binary mixtures diethyl ether/1-propanol, diethyl ether/1-butanol, and diethyl ether/isobutanol. Among the pure solvents investigated in this study best extraction efficacy was obtained with 1-butanol. Synergic effects in the extraction with binary mixtures was investigated and compared with some other systems used for the extraction of poorly extractable compounds. Results obtained in this study may be of both fundamental and practical importance.

  19. The Effect of Cavitating Ultrasound on the Heterogeneous Aqueous Hydrogenation of 3-buten-2-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Chin, Ya-Huei; Peden, Charles HF.

    2004-10-25

    The effect of ultrasound at 20 kHz on the heterogeneous aqueous hydrogenation of 3-buten-2-ol employing a Pd-black catalyst has been studied isothermally at 295 K, forming 2-butanone and 2-butanol products. Our work here shows that adding 1-pentanol as an inert dopant had the effect of inducing cavitation in the ultrasound-treated reaction where it otherwise would not occur. The selectivity showed a 700% increase toward 2-butanol formation and the activity enhanced a factor of 10.8 compared to the noncavitating high-power ultrasound experiment. This study demonstrates that ''inert dopants'' may have use as synthetic tools in sonocatalysis.

  20. Regioselective alkane hydroxylation with a mutant CYP153A6 enzyme

    DOEpatents

    Koch, Daniel J.; Arnold, Frances H.

    2013-01-29

    Cytochrome P450 CYP153A6 from Myobacterium sp. strain HXN1500 was engineered using in-vivo directed evolution to hydroxylate small-chain alkanes regioselectively. Mutant CYP153A6-BMO1 selectively hydroxylates butane and pentane at the terminal carbon to form 1-butanol and 1-pentanol, respectively, at rates greater than wild-type CYP153A6 enzymes. This biocatalyst is highly active for small-chain alkane substrates and the regioselectivity is retained in whole-cell biotransformations.

  1. Effect of release rate and enantiomeric composition on response to pheromones of Megaplatypus mutatus (Chapuis) in poplar plantations of Argentina and Italy.

    PubMed

    Funes, Hernán; Zerba, Eduardo; Gonzalez-Audino, Paola

    2013-10-01

    Megaplatypus mutatus (=Platypus sulcatus Chapuis) is an Ambrosia beetle native to South America, which was recently introduced in Italy and its presence there is causing severe damage to the local poplar plantations. The male M. mutatus pheromone is composed of (S)-(+)-6-methyl-5-hepten-2-ol [(+)-sulcatol], 6-methyl-5-hepten-2-one (sulcatone) and 3-pentanol. A series of field trials testing dose, blend and enantiomer composition performed in Argentina and Italy evaluated attraction and found that the optimal release rate of pheromone components as baits in cross vane baited traps (CIPEIN-CV) was 6, 6 and 30 mg day−1 of sulcatone, (+)-sulcatol and 3-pentanol, respectively. It was also determined that racemic sulcatol is as effective as the pure (+)-isomer for the purpose of beetle catch, due to the inert nature of the (−)-isomer allowing the usage of low cost racemic sulcatol instead of highly expensive (+)-sulcatol. The results of our work contribute to the development of pheromone-based local technologies with low environmental impact and low cost for control or monitoring of an important pest. PMID:23590828

  2. Purification and properties of nitroalkane oxidase from Fusarium oxysporum.

    PubMed Central

    Kido, T; Hashizume, K; Soda, K

    1978-01-01

    A nitroalkane-oxidizing enzyme, which was inducibly formed by addition of nitroethane to the medium was purified to homogeneity from an extract of Fusarium oxysporum (IFO 5942) with an overall yield of about 20%. The enzyme catalyzed the oxidative denitrification of 1-nitropropane as follows: CH2(NO2)CH2CH3 + O2 + H2O leads to OHCCH2CH3 + HNO2 + H2O2. In addition to 1-nitropropane, 3-nitro-2-pentanol, 2-nitropropane, and nitrocyclohexane are good substrates; the enzyme is designated "nitroalkane oxidase" (EC class 1.7.3). The enzyme has a molecular weight of approximately 185,000 and consists of four subunits identical in molecular weight (47,000). Flavin adenine dinucleotide was required for the enzyme activity and could be replaced in part by riboflavin 5'-phosphate. The maximum reactivity was found at about pH 8.0. The enzyme was inhibited significantly by HgCl2, KCN, p-chloromercuribenzoate, and N-ethylmaleimide. The Michaelis constants are as follows: 1-nitropropane, 1.54 mM; 2-nitropropane, 7.40 mM; nitroethane, 1.00 mM; 3-nitro-2-pentanol, 3.08 mM; nitrocyclohexane, 0.90 mM; and flavin adenine dinucleotide, 1.33 micrometer. PMID:22538

  3. Heat transfer in pool boiling of binary and ternary non-azeotropic mixtures

    NASA Astrophysics Data System (ADS)

    Nahra, Ziad; Næss, Erling

    2009-05-01

    Heat transfer coefficients in nucleate pool boiling of binary and ternary non-azeotropic hydrocarbon mixtures were obtained experimentally using a vertical electrically heated cylindrical carbon steel surface at atmospheric pressure with several surface roughness. The fluids used were Methanol/1-Pentanol and Methanol/1-Pentanol/1,2-Propandiol at constant 1,2-Propandiol mole fraction of 30%. Heat fluxes were varied in the range 25-235 kW/m2. The cylindrical heater surface was polished to an average surface roughness of 0.2 μm, and sandblasted yielding surface roughness of 2.98 and 4.35 μm, respectively. The experimental results were compared to available prediction correlations, indicating that the correlations based on the boiling range are in better qualitative agreement than correlations based on the phase envelope. Increasing surface roughness resulted in an increase in the heat transfer coefficient, and the effect was observed to be dependent on the heat flux and fluid composition.

  4. Disposition of short-chain aliphatic alcohols in rabbit vitreous by ocular microdialysis.

    PubMed

    Atluri, Harisha; Mitra, Ashim K

    2003-03-01

    Anatomic and physiological barriers limit drug delivery to the posterior segment of the eye via topical or systemic administration. Intravitreal administration has proven to be a safe and effective means of treating various posterior segment diseases. Elimination of a compound from the vitreous chamber may depend on lipophilicity, diffusivity, and aqueous solubility. This information is critical for optimizing intravitreal dosing which in turn can aid in the design of drug delivery systems. The purpose of this study is to determine the vitreous disposition of an ascending homologous series of short chain aliphatic alcohols ranging from hydrophilic methanol to lipophilic 1-heptanol by microdialysis. Radiolabelled 14C-methanol, 14C-1-propanol, 14C-1-pentanol, and 14C-1-heptanol with log partition coefficient values ranging from -0.77 to 2.7 were studied. Microdialysis probes were implanted in both anterior and vitreous chamber of the rabbit eye to sample aqueous and vitreous humors simultaneously. Concentric probe was implanted in vitreous chamber about 3mm below the cornealscleral limbus. Linear probe was implanted in the anterior chamber using a 25-guage needle. Isotonic phosphate buffer saline (IPBS) (pH 7.4) was perfused through the probe with a flow rate of 2 microlml(-1). Alcohols (2.0 microg-130.72 microg) were injected into the vitreous body. In vitro recovery for the probes was calculated using respective alcohols in IPBS. Pharmacokinetic parameters were determined by non-compartmental analysis. Vitreal elimination half-lives of methanol, 1-propanol, 1-pentanol and 1-heptanol are 52.0+/-5.7, 58.5+/-5.8, 72.9+/-5.8 and 153.7+/-21.6 min, respectively. Dose normalized area under the aqueous concentration time curve values of methanol, 1-propanol and 1-pentanol are 33.8+/-13.4, 28.3+/-11.9 and 29.2+/-4.9 microgminml(-1)microg(-1)10(-2), respectively. Time taken to reach maximum concentration in the anterior chamber for methanol, 1-propanol and 1-pentanol is 120+/-42, 160+/-26, and 260+/-26 min, respectively. The maximum concentration of methanol, 1-propanol and 1-pentanol achieved in the anterior chamber is 18.6+/-10.3, 9.4+/-3.2, and 5.9+/-1.3 microgml(-1)10(-4) respectively. Detectable 1-heptanol levels were not observed in the anterior chamber with the intravitreal dose administered. The shorter vitreal elimination half-lives of the alcohols studied suggest retina as major route of elimination from the vitreous body. The elimination rate constants of alcohols from the vitreous appear to be progressively decreasing with ascending chain length and lipophilicity (methanol to 1-heptanol). Among the alcohols studied, methanol produced the highest concentration in the anterior chamber following vitreal administration. PMID:12573660

  5. Temperature-dependent enantiospecificity of secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus

    SciTech Connect

    Pham, V.T.; Phillips, R.S.; Ljungdahl, L.G.

    1989-03-01

    An alcohol dehydrogenase reported from Thermoanaerobium brockii catalyzes the asymmetric reduction of aliphatic acyclic ketones. An interesting substrate size-induced reversal of stereoselectivity at 37/degree/C was observed by Keinan and co-workers in their studies of this latter enzyme. The smaller substrates (2-butanone, 3-methyl-2-butanone, or methyl cyclopropyl ketone) were reduced to (R)-alcohols, whereas 2-pentanone and the longer chain ketones provided the (S)-alcohols. In order to evaluate the mechanistic basis of this unusual stereochemical reversal, the authors have studied the kinetics of the reaction of SADH from T. ethanolicus with the (R)- and (S)-enantiomers of the simple secondary alcohols, 2-butanol and 2-pentanol.

  6. Interplay of metalloligand and organic ligand to tune micropores within isostructural mixed-metal organic frameworks (M'MOFs) for their highly selective separation of chiral and achiral small molecules.

    PubMed

    Das, Madhab C; Guo, Qunsheng; He, Yabing; Kim, Jaheon; Zhao, Cong-Gui; Hong, Kunlun; Xiang, Shengchang; Zhang, Zhangjing; Thomas, K Mark; Krishna, Rajamani; Chen, Banglin

    2012-05-23

    Four porous isostructural mixed-metal-organic frameworks (M'MOFs) have been synthesized and structurally characterized. The pores within these M'MOFs are systematically tuned by the interplay of both the metalloligands and organic ligands which have enabled us not only to direct their highly selective separation of chiral alcohols 1-phenylethanol (PEA), 2-butanol (BUT), and 2-pentanol (2-PEN) with the highest ee up to 82.4% but also to lead highly selective separation of achiral C(2)H(2)/C(2)H(4) separation. The potential application of these M'MOFs for the fixed bed pressure swing adsorption (PSA) separation of C(2)H(2)/C(2)H(4) has been further examined and compared by the transient breakthrough simulations in which the purity requirement of 40 ppm in the outlet gas can be readily fulfilled by the fixed bed M'MOF-4a adsorber at ambient conditions. PMID:22545712

  7. Correlation and prediction of thermodynamic properties of binary mixtures from perturbed chain statistical associating fluid theory

    NASA Astrophysics Data System (ADS)

    Almasi, Mohammad

    2014-11-01

    Densities and viscosities for binary mixtures of Diethanolamine (DEA) + 2 alkanol (2 propanol up to 2 pentanol) were measured over the entire composition range and temperature interval of 293.15-323.15 K. From the density and viscosity data, values of various properties such as isobaric thermal expansibility, excess isobaric thermal expansibility, partial molar volumes, excess molar volumes and viscosity deviations were calculated. The observed variations of these parameters, with alkanols chain length and temperature, are discussed in terms of the intermolecular interactions between the unlike molecules of the binary mixtures. The ability of the perturbed chain statistical associating fluid theory (PC-SAFT) to correlate accurately the volumetric behavior of the binary mixtures is demonstrated.

  8. Complex formation equilibria of some beta-amino-alcohols with lead(II) and cadmium(II) in aqueous solution.

    PubMed

    Canepari, S; Carunchio, V; Castellano, P; Messina, A

    1998-12-01

    A study of complex formation equilibria of some beta-amino-alcohols with lead(II) and cadmium(II) ions at 25 degrees C and in 0.5 M KNO(3) is reported. The amino-alcohols considered are 2-amino-1-propanol, 2-amino-1-butanol, 2-amino-1-pentanol and 2-amino-1,3-propanediol. sec-Buthylamine and 2-amino-1-methoxy-propane have been also considered for comparison. The results are discussed in terms of ligand structure, paying attention to the number of hydroxyl groups and to the length of the alkyl residual. A weak contribution of the alcoholic oxygen in the coordination of cadmium(II) and the presence of a mixed hydroxyl species in lead(II) containing systems are hypothesized. PMID:18967412

  9. Optical constants of alcohols in the infrared

    NASA Technical Reports Server (NTRS)

    Sethna, P. P.; Williams, D.

    1979-01-01

    The spectral reflectances at near-normal incidence for methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol are reported for the spectral range 6700-350 kaysers. The real and imaginary parts of the complex index of refraction of these liquids are obtained in the range 4000-400 kaysers by use of Kramers-Kronig phase-shift analysis. For all of the alcohols studied, the strength for the OH-stretch bands is directly proportional to the number of OH groups per unit volume; similar relations are established for CH- and CO-stretch bands. Absorption cross sections for stretch vibrations of the three groups are considered, and the role of characteristic group intensities in intensity spectroscopy is discussed.

  10. Hydrated Electrons in a Quaternary Microemulsion System: A Pulse Radiolysis Study

    PubMed

    Adhikari; Joshi; Gopinathan

    1997-07-01

    Using the technique of pulse radiolysis, hydrated electrons have been produced and studied in quaternary microemulsion (sodium lauryl sulfate (NaLS)/water/cyclohexane/1-pentanol) system. Remarkably high lifetimes ( approximately 20 &mgr;s) for hydrated electrons have been obtained. In general, these are two orders of magnitude higher than those reported earlier in reverse micelles. The water droplet sizes and location of the probes have been determined from the decay kinetics of hydrated electrons. The yields and half-lives (t 1/2 ) of the hydrated electrons vary smoothly as the water droplet sizes are changed. We believe that these studies will be useful not only in interpreting electron transfer reactions occurring in small water pockets in biological systems but also in the production of metal nanoclusters by radiation chemical method. PMID:9241228

  11. Bioethanol production optimization: a thermodynamic analysis.

    PubMed

    Alvarez, Víctor H; Rivera, Elmer Ccopa; Costa, Aline C; Filho, Rubens Maciel; Wolf Maciel, Maria Regina; Aznar, Martín

    2008-03-01

    In this work, the phase equilibrium of binary mixtures for bioethanol production by continuous extractive process was studied. The process is composed of four interlinked units: fermentor, centrifuge, cell treatment unit, and flash vessel (ethanol-congener separation unit). A proposal for modeling the vapor-liquid equilibrium in binary mixtures found in the flash vessel has been considered. This approach uses the Predictive Soave-Redlich-Kwong equation of state, with original and modified molecular parameters. The congeners considered were acetic acid, acetaldehyde, furfural, methanol, and 1-pentanol. The results show that the introduction of new molecular parameters r and q in the UNIFAC model gives more accurate predictions for the concentration of the congener in the gas phase for binary and ternary systems. PMID:18418747

  12. Bioethanol Production Optimization: A Thermodynamic Analysis

    NASA Astrophysics Data System (ADS)

    Álvarez, Víctor H.; Rivera, Elmer Ccopa; Costa, Aline C.; Filho, Rubens Maciel; Maciel, Maria Regina Wolf; Aznar, Martín

    In this work, the phase equilibrium of binary mixtures for bioethanol production by continuous extractive process was studied. The process is composed of four interlinked units: fermentor, centrifuge, cell treatment unit, and flash vessel (ethanol-congener separation unit). A proposal for modeling the vapor-liquid equilibrium in binary mixtures found in the flash vessel has been considered. This approach uses the Predictive Soave-Redlich-Kwong equation of state, with original and modified molecular parameters. The congeners considered were acetic acid, acetaldehyde, furfural, methanol, and 1-pentanol. The results show that the introduction of new molecular parameters r and q in the UNIFAC model gives more accurate predictions for the concentration of the congener in the gas phase for binary and ternary systems.

  13. Solvent optimization for niacinamide adsorption on organo-functionalized SBA-15 mesoporous silica

    NASA Astrophysics Data System (ADS)

    Moritz, Michał

    2013-10-01

    This work describes the application of organo-modified SBA-15 siliceous materials as the carrier for niacinamide. The surface functionalization of SBA-15 by a grafting strategy with triethoxyphenylsilane, triethoxy(4-methoxyphenyl)silane, triethoxymethylsilane and (3-mercaptopropyl)trimethoxysilane as modifying agents has been successfully achieved. The adsorption process was performed in acetonitrile, methanol, 2-propanol, 1-pentanol and ethyl acetate. The obtained results indicated a promote niacinamide adsorption on sulfopropyl-modified (119 mg/g) and non-modified (78 mg/g) SBA-15 from ethyl acetate. The pure and derivatized SBA-15 products have been characterized by elemental analysis, thermogravimetry, nitrogen adsorption and diffuse reflectance UV spectroscopy. After niacinamide adsorption the textural parameters of mesoporous carriers such as BET surface area, pore volume and microporosity were reduced. The mesoporous matrices loaded with niacinamide exhibited prolonged-release kinetics of this vitamin, especially from sulfopropyl-modified SBA-15 carrier.

  14. Effect of five enological practices and of the general phenolic composition on fermentation-related aroma compounds in Mencia young red wines.

    PubMed

    Añón, Ana; López, Jorge F; Hernando, Diego; Orriols, Ignacio; Revilla, Eugenio; Losada, Manuel M

    2014-04-01

    The effects of five technological procedures and of the contents of total anthocyanins and condensed tannins on 19 fermentation-related aroma compounds of young red Mencia wines were studied. Multifactor ANOVA revealed that levels of those volatiles changed significantly over the length of storage in bottles and, to a lesser extent, due to other technological factors considered; total anthocyanins and condensed tannins also changed significantly as a result of the five practices assayed. Five aroma compounds possessed an odour activity value >1 in all wines, and another four in some wines. Linear correlation among volatile compounds and general phenolic composition revealed that total anthocyanins were highly related to 14 different aroma compounds. Multifactor ANOVA, considering the content of total anthocyanins as a sixth random factor, revealed that this parameter affected significantly the contents of ethyl lactate, ethyl isovalerate, 1-pentanol and ethyl octanoate. Thus, the aroma of young red Mencia wines may be affected by levels of total anthocyanins. PMID:24262556

  15. Urinary excretion of 2,5-hexanedione and peripheral polyneuropathies in workers exposed to hexane

    SciTech Connect

    Governa, M.; Calisti, R.; Coppa, G.; Tagliavento, G.; Colombi, A.; Troni, W.

    1987-01-01

    Forty shoe factory workers who were exposed to hexane were investigated to see if there was a correlation between electroneuromyographic changes indicative of neuropathy and urinary excretion of 2,5-hexanedione. Urinary samples were analyzed for the presence of the metabolic products of n-hexane and its isomers. Electrodiagnostic examination was carried out following the urinary sampling. A rating scale was used to obtain a cumulative numeric index of electrodiagnostic findings. 2,5-Hexanedione and ..gamma..-valerolactone were discovered in all cases, while 2-hexanol was found in 11 cases. 2,5-Hexanedione was the main metabolite in most cases (39 of 40). Only in 1 case was a low level of 2-methyl-2-pentanol detected; 3-methyl-2-pentanol was never detected. Metabolic products of cyclohexane were present in about one-fifth of the cases, while trichloroethanol, a metabolic product of trichloroethylene, was nearly always present, all at very low concentrations. Electromyographic abnormalities significant for early detection of toxic polyneuropathy were found in 14 cases. A statistically significant correlation of the electroneuromyographic scoring on the urinary concentrations of measured metabolites was observed only with 2,5-hexanedione and ..gamma..-valerolactone, both derived from n-hexane. Since ..gamma..-valerolactone is probably not a true metabolite of n-hexane, the authors results support the hypothesis that polyneuropathies in shoemakers are due to 2,5-hexanedione. For practical purposes the urinary concentration of 2,5-hexanedione can serve as a predictive measurement for early detection of neurotoxic lesions at preclinical states.

  16. Development and evaluation of novel sensing materials for detecting food contamination

    NASA Astrophysics Data System (ADS)

    Sankaran, Sindhuja

    Rapid detection of food-borne volatile organic compounds (VOCs) such as organic acids and alcohols released by bacterial pathogens is being used as an indicator for detecting bacterial contamination in food by our research group. One of our current research thrusts is to develop novel sensors that will be sensitive to specific compounds (at low operating temperature) associated with food safety. This study evaluates two approaches employed to develop sensors for detecting acid and alcohols at low concentrations. Chemoresistive and piezoelectric sensors were developed based on metal oxides and olfactory system based biomaterials, respectively to detect acetic acid, butanol, 3-methyl-1-butanol, 1-pentanol, and 1-hexanol. The metal oxide based sensors were developed by the sol-gel method. A zinc oxide (ZnO) sensor was found to be sensitive to acetic acid with lower detection limit ranging from 13-40 ppm. The three-layered dip-coated gold electrode based ZnO sensors had a LDL of 18 ppm for acetic acid detection. The ZnO-iron oxide (Fe2O3) based nanocomposite sensors were developed to detect butanol operating at 100°C. The 5% Fe/Zn mole ratio based ZnO-Fe2O3 nanocomposite sensors had high correlation coefficients (>0.90) of calibration curves, low butanol LDLs (26 +/- 7 ppm), and lower variation among the sensor responses. The ZnO and ZnO-Fe2O3 nanocomposite sensors showed potential to detect acetic acid and butanol at low concentrations, respectively at 100°C. QCM based olfactory sensors were developed from olfactory receptor and odorant binding protein based sequences to detect low concentrations of acetic acid and alcohols (3-methyl-1-butanol and 1-hexanol), respectively. The average LDLs for acetic acid as well as alcohols detection of the QCM sensors were < 5 ppm. The linear calibration curve based correlation coefficients of the QCM sensors were > 0.80. Finally, a computational simulation based peptide sequences was designed from olfactory receptors and evaluated as sensor material for the detection of alcohols at low concentrations. The results indicated that the QCM sensors exhibited a good sensitivity to 1-hexanol and 1-pentanol with the estimated LDLs in the range of 2-3 ppm and 3-5 ppm, respectively. This research work was successful in developing multiple novel sensing materials to detect alcohols and acid associated with meat contaminations at low concentrations.

  17. Electrophysiological and Behavioral Responses of Male Fall Webworm Moths (Hyphantria cunea) to Herbivory-Induced Mulberry (Morus alba) Leaf Volatiles

    PubMed Central

    Tang, Rui; Zhang, Jin Ping; Zhang, Zhong Ning

    2012-01-01

    Volatile organic compounds (VOCs) were collected from damaged and intact mulberry leaves (Morus alba L., Moraceae) and from Hyphantria cunea larvae by headspace absorption with Super Q columns. We identified their constituents using gas chromatography-mass spectrometry, and evaluated the responses of male H. cunea antennae to the compounds using gas chromatography-flame ionization detection coupled with electroantennographic detection. Eleven VOC constituents were found to stimulate antennae of male H. cunea moths: ?-ocimene, hexanal, cis-3-hexenal, limonene, trans-2-hexenal, cyclohexanone, cis-2-penten-1-ol, 6-methyl-5-hepten-2-one, 4-hydroxy-4-methyl-2-pentanone, trans-3-hexen-1-ol, and 2,4-dimethyl-3-pentanol. Nine of these chemicals were released by intact, mechanically-damaged, and herbivore-damaged leaves, while cis-2-penten-1-ol was released only by intact and mechanically-damaged leaves and ?-ocimene was released only by herbivore-damaged leaves. Results from wind tunnel experiments conducted with volatile components indicated that male moths were significantly more attracted to herbivory-induced volatiles than the solvent control. Furthermore, male moths' attraction to a sex pheromone lure was increased by herbivory-induced compounds and ?-ocimene, but reduced by cis-2-penten-1-ol. A proof long-range field trapping experiment showed that the efficiency of sex pheromone lures in trapping male moths was increased by ?-ocimene and reduced by cis-2-penten-1-ol. PMID:23166622

  18. Optimal Estimation of Residual Non-Aqueous Phase Liquid Residual Saturations Using Inter-Well Tracer Test Data at OU1 Test Cell, Hill AFB

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Graham, W. D.; Annable, M. D.; Hatfield, K.; Rao, P.

    2001-05-01

    Inter-well tracer tests (IWTT) were conducted at the OU1 test cell at Hill AFB to characterize its hydrogeochemical properties. The test cell was constructed in an aquifer historically contaminated by light nonaqueous phase liquids (LNAPL) such as aviation fuels (JP4) and smaller amounts of chlorinated solvents. Concentrations of a nonpartitioning tracer (bromide) and a number of partitioning tracers (notably, 2,2-Dimethyl-3-Pentanol) were measured at 12 multilevel samplers within the test cell. Assuming the unknown hydraulic conductivity distribution and NAPL distribution can be represented by two random fields, a distributed parameter extended Kalman Filter was developed based upon the three-dimensional advection-dispersion-retardation equations. The nonpartitioning tracer concentration data was used in the Kalman filter to optimally estimate Darcy flux distribution, while the partitioning tracer concentration data was used to optimally estimate residual NAPL distribution. Both the estimated parameter distributions and estimation accuracy were quantified. The estimated NAPL distribution from the inverse stochastic model compared favorably to those derived from soil core and temporal moment analysis.

  19. Synthesis of Short-Chain Diols and Unsaturated Alcohols from Secondary Alcohol Substrates by the Rieske Nonheme Mononuclear Iron Oxygenase MdpJ

    PubMed Central

    Schäfer, Franziska; Schuster, Judith; Würz, Birgit; Härtig, Claus; Harms, Hauke; Müller, Roland H.

    2012-01-01

    The Rieske nonheme mononuclear iron oxygenase MdpJ of the fuel oxygenate-degrading bacterial strain Aquincola tertiaricarbonis L108 has been described to attack short-chain tertiary alcohols via hydroxylation and desaturation reactions. Here, we demonstrate that also short-chain secondary alcohols can be transformed by MdpJ. Wild-type cells of strain L108 converted 2-propanol and 2-butanol to 1,2-propanediol and 3-buten-2-ol, respectively, whereas an mdpJ knockout mutant did not show such activity. In addition, wild-type cells converted 3-methyl-2-butanol and 3-pentanol to the corresponding desaturation products 3-methyl-3-buten-2-ol and 1-penten-3-ol, respectively. The enzymatic hydroxylation of 2-propanol resulted in an enantiomeric excess of about 70% for the (R)-enantiomer, indicating that this reaction was favored. Likewise, desaturation of (R)-2-butanol to 3-buten-2-ol was about 2.3-fold faster than conversion of the (S)-enantiomer. The biotechnological potential of MdpJ for the synthesis of enantiopure short-chain alcohols and diols as building block chemicals is discussed. PMID:22752178

  20. Two Volatile Organic Compounds Trigger Plant Self-Defense against a Bacterial Pathogen and a Sucking Insect in Cucumber under Open Field Conditions

    PubMed Central

    Song, Geun Cheol; Ryu, Choong-Min

    2013-01-01

    Systemic acquired resistance (SAR) is a plant self-defense mechanism against a broad-range of pathogens and insect pests. Among chemical SAR triggers, plant and bacterial volatiles are promising candidates for use in pest management, as these volatiles are highly effective, inexpensive, and can be employed at relatively low concentrations compared with agrochemicals. However, such volatiles have some drawbacks, including the high evaporation rate of these compounds after application in the open field, their negative effects on plant growth, and their inconsistent levels of effectiveness. Here, we demonstrate the effectiveness of volatile organic compound (VOC)-mediated induced resistance against both the bacterial angular leaf spot pathogen, Pseudononas syringae pv. lachrymans, and the sucking insect aphid, Myzus persicae, in the open field. Using the VOCs 3-pentanol and 2-butanone where fruit yields increased gave unexpectedly, a significant increase in the number of ladybird beetles, Coccinella septempunctata, a natural enemy of aphids. The defense-related gene CsLOX was induced by VOC treatment, indicating that triggering the oxylipin pathway in response to the emission of green leaf volatiles can recruit the natural enemy of aphids. These results demonstrate that VOCs may help prevent plant disease and insect damage by eliciting induced resistance, even in open fields. PMID:23698768

  1. Ruthenium-catalyzed α-(hetero)arylation of saturated cyclic amines: reaction scope and mechanism.

    PubMed

    Peschiulli, Aldo; Smout, Veerle; Storr, Thomas E; Mitchell, Emily A; Eliáš, Zdeněk; Herrebout, Wouter; Berthelot, Didier; Meerpoel, Lieven; Maes, Bert U W

    2013-07-29

    Transition-metal-catalyzed sp(3) C-H activation has emerged as a powerful approach to functionalize saturated cyclic amines. Our group recently disclosed a direct catalytic arylation reaction of piperidines at the α position to the nitrogen atom. 1-(Pyridin-2-yl)piperidine could be smoothly α-arylated if treated with an arylboronic ester in the presence of a catalytic amount of [Ru3(CO)12] and one equivalent of 3-ethyl-3-pentanol. A systematic study on the substrate and reagent scope of this transformation is disclosed in this paper. The effect of substitution on both the piperidine ring and the arylboronic ester has been investigated. Smaller (pyrrolidine) and larger (azepane) saturated ring systems, as well as benzoannulated derivatives, were found to be compatible substrates with the α-arylation protocol. The successful use of a variety of heteroarylboronic esters as coupling partners further proved the power of this direct functionalization method. Mechanistic studies have allowed for a better understanding of the catalytic cycle of this remarkable transformation featuring an unprecedented direct transmetalation on a Ru(II)-H species. PMID:23780756

  2. Aroma enhancement and enzymolysis regulation of grape wine using β-glycosidase

    PubMed Central

    Zhu, Feng-Mei; Du, Bin; Li, Jun

    2014-01-01

    Adding β-glycosidase into grape wine for enhancing aroma was investigated using gas chromatography-mass spectrometry (GC-MS) and Kramer sensory evaluation. Compared with the extract from control wines, the extract from enzyme-treated wines increased more aromatic compounds using steam distillation extraction (SDE) and GC-MS analyses. Theses aromatic compounds were as follows: 3-methyl-1-butanol formate, 3-pentanol, furfural, 3-methyl-butanoic acid, 2-methyl-butanoic acid, 3-hydroxy-butanoic acid ethyl ester, hexanoic acid, hexanoic acid ethyl ester, benzyl alcohol, octanoic acid, octanoic acid ethyl ester, dodecanoic acid, and ethyl ester. The enzymolysis regulation conditions, including enzymolysis temperature, enzymolysis time, and enzyme amount, were optimized through L9(34) orthogonal test. Kramer sensory evaluation was performed by an 11-man panel of judges. The optimum enzymolysis regulation conditions were found to be temperature of 45°C, enzymolysis time of 90 min, and enzyme amount of 58.32 U/mL grape wine, respectively. The Kramer sensory evaluation supported that the enzyme-treated wines produced a stronger fragrance. PMID:24804072

  3. Dislodgement effect of natural semiochemicals released by disturbed triatomines: a possible alternative monitoring tool.

    PubMed

    Minoli, Sebastián; Palottini, Florencia; Crespo, Jose Guillermo; Manrique, Gabriel

    2013-12-01

    The quick detection of domestic and peridomestic triatomines in their environments becomes difficult without the use of dislodgement substances that flush them out from their shelters. At present, tetramethrin 0.2% is being widely used in control programs. Although it is an efficient dislodging agent, its toxicity might affect the health of captured triatomines, of other insects and, to a lesser extent, of other animals, including humans. Here, we tested if semiochemicals released by disturbed adults of Triatoma infestans and/or Rhodnius prolixus can make larvae of the same species exit from their refuges. In a walking olfactometer we found that: 1) larvae of T. infestans were repelled by the odors released by disturbed adults of their own species and of R. prolixus, 2) larvae of R. prolixus did not change their behavior in the presence of odors released by adults of both species, and 3) activity levels were not modulated by these odors in any of both species. Besides, in pseudo-natural conditions we found an increased flushing-out activity of larvae of T. infestans when their shelters were sprayed with isobutyric acid or 3-pentanol, and of larvae of R. prolixus when sprayed with 3-methyl-1-butanol. We succeeded in this work to dislodge larvae of triatomines from artificial shelters using natural volatile compounds, allowing the capture of live bugs for further investigations (e.g., xenodiagnosis or genetic studies) and favoring ecological aspects (e.g., minimizing environmental insecticide-contamination and non-targeted mortality). PMID:24581366

  4. Aroma composition changes in early season grapefruit juice produced from thermal concentration.

    PubMed

    Lin, Jianming; Rouseff, Russell L; Barros, Sandy; Naim, Michael

    2002-02-13

    Differences in aroma components and total volatiles between a single unpasteurized Marsh grapefruit juice and its 65 Brix concentrate reconstituted to 10 Brix were examined using GC-olfactometry (GC-O) and GC-FID. Total volatiles (FID) in the reconstituted concentrate were reduced to less than 5% of initial values, but 57% of total aroma (GC-O) remained. Forty-one aroma-active compounds were observed in unpasteurized single strength juice, whereas 27 components were found in the unflavored reconstituted concentrate. Aroma-active compounds were classified into grapefruit/sulfury, sweet/fruity, fresh/citrusy, green/fatty/metallic, and cooked/meaty groups. Five of six components in the sweet/fruity and 14 of 18 green/fatty/metallic components survived thermal concentration. However, only 4-mercapto-4-methyl-2-pentanone in the grapefruit/sulfury group, and linalool and nootkatone from the fresh/citrusy group, were found in the reconstituted concentrate. Methional was the only aroma compound in the cooked/meaty category found in both juice types. beta-Damascenone and 1-p-menthen-8-thiol were found only in the reconstituted concentrate. 4-Mercapto-4-methyl-2-pentanol was found for the first time in grapefruit juice. PMID:11829649

  5. Studies on the interaction between ethanol and two industrial solvents (methyl isobutyl ketone) in mice

    SciTech Connect

    Granvil, C.P.; Sharkawi, M.; Plaa, G.L. )

    1991-03-11

    Methyl n-butyl ketone (MnBK) and methyl isobutyl ketone (MiBK) prolong the duration of ethanol-induced loss of righting reflex (EILRR) in mice. MnBK was almost twice as potent in this regard. To explain this difference, the metabolism of both ketones was studied in male CD-1 mice using GC. MiBK was converted to 4-methyl-2-pentanol (4MPOL) and 4-hydroxy methyl isobutyl ketone (HMP). MnBK metabolites were 2-hexanol (2HOL) and 2,5-hexanedione (2,5HD). The effects of both ketones and metabolites on EILRR and ethanol (E) elimination were studied in mice. The ketones and their metabolites were dissolved in corn oil and injected intraperitoneally 30 min before E 4g/kg for EILRR and 2g/kg for E elimination. In the following doses: MnBK, 5; MiBK, 5; 2HOL, 2.5; 4MPOL, 2.5; and HMP 2.5, significantly prolonged EILRR. Concentrations of E in blood and brain upon return of the righting reflex were similar in solvent-treated and control animals. The mean elimination rate of E was slower in groups given MnBK or 2HOL than in control animals. No change in E elimination was observed with MiBK, HMP, 4MPOL, or 2, 5HD.

  6. Interplay of Metalloligand and Organic Ligand to Tune Micropores within Isostructural Mixed-Metal Organic Frameworks (M MOFs) for Their Highly Selective Separation of Chiral and Achiral Small Molecules

    SciTech Connect

    Madhab, Das; He, Yabing; Kim, Jaheon; Guo, Qunsheng; Zhao, Cong-Gui; Hong, Kunlun; Xiang, Sheng-Chang; Zhang, Zhangjing; Thomas, K Mark; Krishna, Rajamani; Chen, Banglin

    2012-01-01

    Four porous isostructural mixed-metal-organic frameworks (M'MOFs) have been synthesized and structurally characterized. The pores within these M'MOFs are systematically tuned by the interplay of both the metalloligands and organic ligands which have enabled us not only to direct their highly selective separation of chiral alcohols 1-phenylethanol (PEA), 2-butanol (BUT), and 2-pentanol (2-PEN) with the highest ee up to 82.4% but also to lead highly selective separation of achiral C{sub 2}H{sub 2}/C{sub 2}H{sub 4} separation. The potential application of these M'MOFs for the fixed bed pressure swing adsorption (PSA) separation of C{sub 2}H{sub 2}/C{sub 2}H{sub 4} has been further examined and compared by the transient breakthrough simulations in which the purity requirement of 40 ppm in the outlet gas can be readily fulfilled by the fixed bed M'MOF-4a adsorber at ambient conditions.

  7. Experimental and computational study of the effect of alcohols on the solution and adsorption properties of a nonionic symmetric triblock copolymer.

    PubMed

    Liu, Xiaomeng; He, Feng; Salas, Carlos; Pasquinelli, Melissa A; Genzer, Jan; Rojas, Orlando J

    2012-02-01

    This study investigates the effect of alcohols on the solution and adsorption properties of symmetric triblock nonionic copolymers comprising blocks of ethylene oxide (EO) and propylene oxide (PO) (EO(37)PO(56)EO(37)). The cloud point, surface tension, critical micelle concentration (CMC), and maximum packing at the air-water interface are determined, and the latter is compared to the amount of polymer that adsorbs from solution onto polypropylene (PP) and cellulose surfaces. The interaction energy and radius of micelles are calculated by using molecular dynamics (MD) simulations. Equivalent MD bead parameters were used in dynamic density functional theory (DDFT) simulations to study the influence of alcohols on the phase behavior of EO(37)PO(56)EO(37) and its adsorption on PP from aqueous solutions. The simulation results agree qualitatively with the experimental observations. Ethanol acts as a good cosolvent for EO(37)PO(56)EO(37) and reduces the amount of EO(37)PO(56)EO(37) that adsorbs on PP surfaces; however, little or no influence is observed on the adsorption on cellulose. Interestingly, longer chain alcohols, such as 1-pentanol, produce the opposite effect. Overall, the solution and adsorption properties of nonionic symmetric triblock copolymers in the presence of alcohols are rationalized by changes in solvency and the hydrophobic effect. PMID:22188471

  8. Effect of paper porosity on OCT images: Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Kirillin, Mikhail Yu.; Priezzhev, Alexander V.; Myllylä, Risto

    2008-06-01

    Non-invasive measurement of paper porosity is an important problem for papermaking industry. Presently used techniques are invasive and require long time for processing the sample. In recent years optical coherence tomography (OCT) has been proved to be an effective tool for non-invasive study of optically non-uniform scattering media including paper. The aim of present work is to study the potential ability of OCT for sensing the porosity of a paper sample by means of numerical simulations. The paper sample is characterized by variation of porosity along the sample while numerical simulations allow one to consider the samples with constant porosity which is useful for evaluation of the technique abilities. The calculations were performed implementing Monte Carlo-based technique developed earlier for simulation of OCT signals from multilayer paper models. A 9-layer model of paper consisting of five fiber layers and four air layers with non-planar boundaries was considered. The porosity of the samples was varied from 30 to 80% by varying the thicknesses of the layers. The simulations were performed for model paper samples without and with optical clearing agents (benzyl alcohol, 1-pentanol, isopropanol) applied. It was shown that the simulated OCT images of model paper with various porosities significantly differ revealing the potentiality of the OCT technique for sensing the porosity. When obtaining the images of paper samples with optical clearing agents applied, the inner structure of the samples is also revealed providing additional information about the samples under study.

  9. Enhancement of Curcumin Fluorescence by Ascorbic Acid in Bicontinuous Microemulsion.

    PubMed

    Iwunze, Maurice O

    2015-07-01

    Steady-state fluorescence spectro-photometric technique is used in this work to determine the chemical parameters of the complex formed between curcumin and ascorbic acid in bicontinuous microemuslion (Bμen). The Bμen liquid used is made up of a four-components system (water-oil-surfactant and co-surfactant (1-pentanol)) in the ratio of 42.11:13.7:21.34:22.85 % w/w. The oil and surfactant used are tetradecane and cetyltrimethylammonium bromide. Curcumin is known to have low solubility in water, but liberally soluble in Bμen, hence the use of Bμen in this study. The observed fluorescence intensity of curcumin was enhanced by introduction of ascorbic acid to the curcumin solution. The increase in the fluorescence intensity showed a very good linearity with a regression coefficient of 0.9974. The association constant, Ka, that resulted between curcumin and ascorbic acid was calculated as 2.15 × 10(4) with the free energy of association, ∆Ga, of -24.71 kJ/mol. The ratio of the complex that was formed by these two molecules was determined as 1:1. PMID:25943984

  10. Size and Fiber Density Controlled Synthesis of Fibrous Nanosilica Spheres (KCC-1)

    PubMed Central

    Bayal, Nisha; Singh, Baljeet; Singh, Rustam; Polshettiwar, Vivek

    2016-01-01

    We report a facile protocol for the synthesis of fibrous nano-silica (KCC-1) with controllable size and fiber density. In this work, we have shown that the particle size, fiber density, surface area and pore volume of KCC-1 can be effectively controlled and tuned by changing various reaction parameters, such as the concentrations of urea, CTAB, 1-pentanol, reaction time, temperature, solvent ratio, and even outside stirring time. For the first time, we were able to control the particle size ranging from as small as 170 nm to as large as 1120 nm. We were also able to control the fiber density from low to medium to very dense, which consequently allowed the tuning of the pore volume. We were able to achieve a pore volume of 2.18 cm3/g, which is the highest reported for such a fibrous material. Notably we were even able to increase the surface area up to 1244 m2/g, nearly double the previously reported surface area of KCC-1. Thus, one can now synthesize KCC-1 with various degrees of size, surface area, pore volume, and fiber density. PMID:27118152

  11. Determination of alcohol compounds using corona discharge ion mobility spectrometry.

    PubMed

    Han, Hai-yan; Huang, Guo-dong; Jin, Shun-ping; Zheng, Pei-chao; Xu, Guo-hua; Li, Jian-quan; Wang, Hong-mei; Chu, Yan-nan

    2007-01-01

    Ion mobility spectrometry (IMS) is a very fast, highly sensitive, and inexpensive technique, it permits efficient monitoring of volatile organic compounds like alcohols. In this article, positive ion mobility spectra for six alcohol organic compounds have been systematically studied for the first time using a high-resolution IMS apparatus equipped with a discharge ionization source. Utilizing protonated water cluster ions (H2O)n H+ as the reactant ions and clean air as the drift gas, alcohol organic compounds, ethanol, 1-propanol, 2-propanol, 1-butanol, 1-pentanol and 2-octanol, all exhibit product ion characteristic peaks in their respective ion mobility spectrometry, that is a result of proton transfer reactions between the alcohols and reaction ions (H2O)n H+. The mixture of these alcohols, including two isomers, has been detected, and the results showed that they could be distinguished effectively in the ion mobility spectrum. The reduced mobility values have been determined, which are in very well agreement with the traditional 63Ni-IMS experimental values. The exponential dilution method was used to calibrate the alcohol concentrations, and a detection limit available for the alcohols is in order of magnitude of a few ng/L. PMID:17969651

  12. Analysis of volatile compounds and triglycerides of seed oils extracted from different poppy varieties (Papaver somniferum L.).

    PubMed

    Krist, Sabine; Stuebiger, Gerald; Unterweger, Heidrun; Bandion, Franz; Buchbauer, Gerhard

    2005-10-19

    Poppy seed oil (Oleum Papaveris Seminis) is used for culinary and pharmaceutical purposes, as well as for making soaps, paints, and varnishes. Astonishingly, hardly anything was yet known about the volatile compounds of this promising comestible. Likewise, there are no current published data about the triglyceride (TAG) composition of poppy seed oils available. In this investigation solid-phase microextraction (SPME) with DVB/Carboxen/PDMS Stable-Flex fiber was applied to the study of volatile compounds of several seed oil samples from Papaver somniferum L. (Papaveraceae). 1-Pentanol (3.3-4.9%), 1-hexanal (10.9-30.9%), 1-hexanol (5.3-33.7%), 2-pentylfuran (7.2-10.0%), and caproic acid (2.9-11.5%) could be identified as the main volatile compounds in all examined poppy seed oil samples. Furthermore, the TAG composition of these oils was analyzed by MALDI-ReTOF- and ESI-IT-MS/MS. The predominant TAG components were found to be composed of linoleic, oleic, and palmitic acid, comprising approximately 70% of the oils. TAG patterns of the different poppy varieties were found to be very homogeneous, showing also no significant differences in terms of the applied pressing method of the plant seeds. PMID:16218681

  13. The effect of medium chain length alcohols on the micellar properties of sodium dodecyl sulfate in sodium chloride solutions

    SciTech Connect

    Foerland, G.M.; Hoeiland, H. . Dept. of Chemistry); Samseth, J. ); Mortensen, K. )

    1994-04-01

    The effect of medium chain length alcohols on the micellar size and shape of sodium dodecyl sulfate in electrolyte solutions has been investigated by means of small angle neutron scattering (SANS), dynamic light scattering (DLS), and viscosity measurements. The surfactant content was kept constant throughout, at 0.04 m, and the alcohols used were 1-butanol, 1-pentanol, and 1-hexanol. The data from the various techniques are qualitatively in agreement. The SANS data generally fit a model for prolate ellipsoids with varying ratios of the major to minor axis. Addition of butanol first leads to a decrease in micellar size, the major to minor axis ratio decreases from about 6 to less than 2. However, as the butanol concentration exceeds 0.5 m, the micelles starts to grow again. The same can be seen from the diffusion coefficient as measured by DLS. Addition of pentanol or hexanol do not bring about this minimum in micellar size. The minor axis decreases and the major axis increases as these alcohols are added. Thus these alcohols make the prolate ellipsoidal micelles grow continuously towards large rod-like structures. The viscosity data are less detailed, but confirm the general trend upon alcohol addition.

  14. An endophyte of Picrorhiza kurroa Royle ex. Benth, producing menthol, phenylethyl alcohol and 3-hydroxypropionic acid, and other volatile organic compounds.

    PubMed

    Qadri, Masroor; Deshidi, Ramesh; Shah, Bhawal Ali; Bindu, Kushal; Vishwakarma, Ram A; Riyaz-Ul-Hassan, Syed

    2015-10-01

    An endophytic fungus, PR4 was found in nature associated with the rhizome of Picrorhiza kurroa, a high altitude medicinal plant of Kashmir Himalayas. The fungus was found to inhibit the growth of several phyto-pathogens by virtue of its volatile organic compounds (VOCs). Molecular phylogeny, based on its ITS1-5.8S-ITS2 ribosomal gene sequence, revealed the identity of the fungus as Phomopsis/Diaporthe sp. This endophyte was found to produce a unique array of VOCs, particularly, menthol, phenylethyl alcohol, (+)-isomenthol, β-phellandrene, β-bisabolene, limonene, 3-pentanone and 1-pentanol. The purification of compounds from the culture broth of PR4 led to the isolation of 3-hydroxypropionic acid (3-HPA) as a major metabolite. This is the first report of a fungal culture producing a combination of biologically and industrially important metabolites—menthol, phenylethyl alcohol, and 3-HPA. The investigation into the monoterpene biosynthetic pathway of PR4 led to the partial characterization of isopiperitenone reductase (ipr) gene, which seems to be significantly distinct from the plant homologue. The biosynthesis of plant-like-metabolites, such as menthol, is of significant academic and industrial significance. This study indicates that PR4 is a potential candidate for upscaling of menthol, phenylethyl alcohol, and 3-HPA, as well as for understanding the menthol/monoterpene biosynthetic pathway in fungi. PMID:26220851

  15. Effect of Fresh Garlic on Lipid Oxidation and Microbiological Changes of Pork Patties during Refrigerated Storage

    PubMed Central

    2014-01-01

    The effects of two levels (1.4 vs 2.8%) of fresh garlic on lipid oxidation and microbial growth in pork patties were evaluated. Hunter color (L, a, b), pH, thiobarbituric acid reactive substances (TBARS), oxidative volatile compounds, total bacteria and Enterobacteriaceae in the pork patties with or without fresh garlic were measured during storage at 4℃. Addition of fresh garlic decreased redness (a), while increased pH and yellowness (b) values of the fresh pork patties were observed, regardless of the levels added. The TBARS values of the pork patties were increased with the addition of fresh garlic (p<0.05). Similar results were observed in oxidative volatile compounds. A total of 13 volatile compounds were detected in the patties (5 sulfur-containing compounds, including allyl mercaptan, allyl methyl sulfide, diallyl sulfide, methyl-(E)-propenyl-disulfide, and diallyl disulfide, and the 8 other oxidative compounds, including 1-pentanol, hexanal, 1-hexanol, heptanal, (E)-2-heptenal, 1-octen-3-ol, (E)-2-octenal and nonanal). Fresh garlic accelerated development of oxidative products in the pork patties, especially hexanal and the total oxidative volatile compounds. However, the addition of 1.4 and 2.8% of fresh garlic inhibited the growth of total bacteria and Enterobacteriaceae, indicating low total bacterial counts and Enterobacteriaceae than the controls. PMID:26761498

  16. Monitoring of HAART regime antiretrovirals in serum of acquired immunodeficiency syndrome patients by micellar liquid chromatography.

    PubMed

    Casas-Breva, I; Peris-Vicente, J; Rambla-Alegre, M; Carda-Broch, S; Esteve-Romero, J

    2012-09-21

    A methodology based on micellar liquid chromatography to monitor five antiretroviral drugs (lamivudine, stavudine, tenofovir, zidovudine and efavirenz) was proposed. Antiretrovirals were studied in sets of three, corresponding to each highly active antiretroviral therapy (HAART) regime, prescribed to acquired immunodeficiency syndrome (AIDS)-infected patients. Four aqueous micellar mobile phases buffered at pH 7 were optimized to separate these compounds, using sodium dodecyl sulfate as the tensioactive, and 1-propanol or 1-pentanol as the organic modifier. The composition of each mobile phase was optimized for each antiretroviral. The common separation conditions were: C18 apolar column (125 × 4.6 mm, 5 μm particle size), UV detection set at 214 nm, and mobile phase running at 1 mL min(-1) without controlling the temperature. The finally suggested method was validated for five analysed antiretroviral drugs following the US Food and Drug Administration guidelines in terms of: linearity between 0.5 and 50 ppm (r(2) > 0.9995), sensitivity (LOD lower than 0.25 ppm), intra- and inter-day precision (<7.1 and <5.2%, respectively) and accuracy (recovery 88.5-105.3% and 93.5-101.3%, respectively), as well as robustness (<6.5%). The proposed method was used to monitor the level of antiretrovirals in the serum of AIDS patients. The suggested methodology was found to be useful in the routine analysis of antiretrovirals in serum samples. PMID:22858583

  17. Nucleation of ethanol, propanol, butanol, and pentanol: a systematic experimental study along the homologous series.

    PubMed

    Manka, Alexandra A; Wedekind, Jan; Ghosh, David; Hhler, Kristina; Wlk, Judith; Strey, Reinhard

    2012-08-01

    We present homogeneous vapor-liquid nucleation rates of the 1-alcohols (C(n)H(2n+1)OH, n = 2-4) measured in the well-established two-valve nucleation pulse chamber as well as in a novel one-piston nucleation pulse chamber at temperatures between 235 and 265 K. The nucleation rates and critical cluster sizes show a very systematic behavior with respect to the hydrocarbon chain length of the alcohol, just as their thermo-physical parameters such as surface tension, vapor pressure, and density would suggest. For all alcohols, except ethanol, predictions of classical nucleation theory lie several orders of magnitude below the experimental results and show a strong temperature-dependence typically found in nucleation experiments. The more recent Reguera-Reiss theory [J. Phys. Chem. B 108(51), 19831 (2004)] achieves reasonably good predictions for 1-propanol, 1-butanol, and 1-pentanol, and independent of the temperature. Ethanol, however, clearly shows the influence of strong association between molecules even in the vapor phase. We also scaled all experimental results with classic nucleation theory to compare our data with other data from the literature. We find the same overall temperature trend for all measurement series together but inverted and inconsistent temperature trends for individual 1-propanol and 1-butanol measurements in other devices. Overall, our data establishe a comprehensive and reliable data set that forms an ideal basis for comparison with nucleation theory. PMID:22894357

  18. Density gradient theory combined with the PC-SAFT equation of state used for modeling the surface tension of associating systems

    NASA Astrophysics Data System (ADS)

    Vinš, Václav; Planková, Barbora; Hrubý, Jan; Celný, David

    2014-03-01

    The density gradient theory (GT) combined with a SAFT-type (Statistical Associating Fluid Theory) equation of state has been used for modeling the surface tension of associating fluids represented by a series of six alkanols ranging from methanol to 1-pentanol. The effect of nonzero dipole moment of the selected alkanols on the predicted surface tension was investigated in this study. Results of the GT + non-polar Perturbed Chain (PC) SAFT equation of state were compared to predictions of GT combined with the PC-polar-SAFT, i.e. PCP-SAFT, equation. Both GT + PC-SAFT and GT + PCP-SAFT give reasonable prediction of the surface tension for pure alkanols. Results of both models are comparable as no significant difference in the modeled saturation properties and in the predicted surface tension using GT was found. Consideration of dipolar molecules of selected alkanols using PCP-SAFT had only minor effect on the predicted properties compared to the non-polar PC-SAFT model.

  19. Pentynyl dextran as a support matrix for immobilization of serine protease subtilisin Carlsberg and its use for transesterification of N-acetyl-L-phenylalanine ethyl ester in organic media.

    PubMed

    Tahir, Muhammad Nazir; Cho, Eunae; Mischnick, Petra; Lee, Jae Yung; Yu, Jae-Hyuk; Jung, Seunho

    2014-04-01

    In this study, serine protease (subtilisin Carlsberg) was immobilized on pentynyl dextran (PyD, O-alkynyl ether of dextran, 1) and used for the transesterification of N-acetyl-L-phenylalanine ethyl ester (2) with different aliphatic (1-propanol, 1-butanol, 1-pentanol, 1-hexanol) and aromatic (benzyl alcohol, 2-phenyl ethanol, 4-phenyl-1-butanol) alcohols in tetrahydrofuran (THF). The effect of carbon chain length in aliphatic and aromatic alcohols on initial and average transesterification rate, transesterification activity of immobilized enzyme and yield of the reaction under selected reaction conditions was investigated. The transesterification reactivity of the enzyme and yield of the reaction increased as the chain length of the alcohols decreased. Furthermore, almost no change in yield was observed when the immobilized enzyme was repeatedly used for selected alcohols over six cycles. Intrinsic fluorescence analysis showed that the catalytic activity of the immobilized enzyme in THF was maintained due to retention of the tertiary structure of the enzyme after immobilization on PyD (1). PMID:23978850

  20. Synthesis and chemical modifications of in-situ grown anatase TiO2 microspheres with isotropically exposed {0 0 1} facets for superhydrophobic and self-cleaning properties

    NASA Astrophysics Data System (ADS)

    Hu, Wanbiao; Yu, Yuanlie; Chen, Hua; Lau, Kenny; Craig, Vincent; Brink, Frank; Withers, Ray L.; Liu, Yun

    2015-12-01

    Excellent and robust hydrophobic materials generally benefit from specifically exposed surfaces i.e. always the low-energy surfaces, and well-defined micro/nano-structures that are achieved through advanced facilities and complicated process with a high cost. We hereof demonstrate that the superhydrophobicity and further self-cleaning properties are also attainable based on high-energy crystalline facets by an appropriate chemical modification. Specifically, anatase TiO2 microspheres were large-scale synthesized to exhibit isotropically exposed high-energy {0 0 1} facets through optimizing the HF/H2O2/H2O ratio during hydrothermal processes. The formation of the microspheres was uncovered to be an in-situ "growth-cum-assembly" grown mechanism. Such high-energy {0 0 1} facets facilitate the strong coupling between the resultant TiO2 microspheres and the modifier (2,2,3,3,4,4,5,5-octafluoro-1-pentanol) because the {0 0 1} facets offer abundant active sites for chemical bonding, showing great merits for superhydrophobicity (with water contact angle of 154 ± 2°, 6 μl droplets), and further stably surface self-cleaning i.e. easily removing surface contamination (e.g. Al2O3 powders). This integrated strategy represents a milestone in design and fabrication of delicate composites with high-energy surfaces for specific functions and properties.

  1. Characterization of the most odor-active volatiles of orange wine made from a Turkish cv. Kozan (Citrus sinensis L. Osbeck).

    PubMed

    Selli, Serkan; Canbas, Ahmet; Varlet, Vincent; Kelebek, Hasim; Prost, Carole; Serot, Thierry

    2008-01-01

    The aroma-active compounds of cv. Turkish Kozan orange wine were analyzed by sensory and instrumental analyses. Liquid-liquid extraction with dichloromethane was used for extraction of volatile components. According to sensory analysis, the aromatic extract obtained by liquid-liquid extraction was representative of orange wine odor. A total of 63 compounds were identified and quantified in orange wine. The results of the gas chromatography-olfactometry analysis showed that 35 odorous compounds were detected by the panelists. Of these, 28 aroma-active compounds were identified. Alcohols followed by terpenes and esters were the most abundant aroma-active compounds of the orange wine. Among these compounds, ethyl butanoate (fruity sweet), 3-methyl-1-pentanol (roasty), linalool (floral citrusy), gamma-butyrolactone (cheesy burnt sugar), 3-(methylthio)-propanol (boiled potato, rubber), geraniol (floral citrusy), and 2-phenylethanol (floral rose) were the most important contributors to the aroma of the orange wine because they were perceived by all eight panelists. PMID:18078317

  2. Effect of Fresh Garlic on Lipid Oxidation and Microbiological Changes of Pork Patties during Refrigerated Storage.

    PubMed

    Park, Sung Yong; Chin, Koo Bok

    2014-01-01

    The effects of two levels (1.4 vs 2.8%) of fresh garlic on lipid oxidation and microbial growth in pork patties were evaluated. Hunter color (L, a, b), pH, thiobarbituric acid reactive substances (TBARS), oxidative volatile compounds, total bacteria and Enterobacteriaceae in the pork patties with or without fresh garlic were measured during storage at 4℃. Addition of fresh garlic decreased redness (a), while increased pH and yellowness (b) values of the fresh pork patties were observed, regardless of the levels added. The TBARS values of the pork patties were increased with the addition of fresh garlic (p<0.05). Similar results were observed in oxidative volatile compounds. A total of 13 volatile compounds were detected in the patties (5 sulfur-containing compounds, including allyl mercaptan, allyl methyl sulfide, diallyl sulfide, methyl-(E)-propenyl-disulfide, and diallyl disulfide, and the 8 other oxidative compounds, including 1-pentanol, hexanal, 1-hexanol, heptanal, (E)-2-heptenal, 1-octen-3-ol, (E)-2-octenal and nonanal). Fresh garlic accelerated development of oxidative products in the pork patties, especially hexanal and the total oxidative volatile compounds. However, the addition of 1.4 and 2.8% of fresh garlic inhibited the growth of total bacteria and Enterobacteriaceae, indicating low total bacterial counts and Enterobacteriaceae than the controls. PMID:26761498

  3. Rapid ester biosynthesis screening reveals a high activity alcohol-O-acyltransferase (AATase) from tomato fruit.

    PubMed

    Lin, Jyun-Liang; Zhu, Jie; Wheeldon, Ian

    2016-05-01

    Ethyl and acetate esters are naturally produced in various yeasts, plants, and bacteria. The biosynthetic pathways that produce these esters share a common reaction step, the condensation of acetyl/acyl-CoA with an alcohol by alcohol-O-acetyl/acyltransferase (AATase). Recent metabolic engineering efforts exploit AATase activity to produce fatty acid ethyl esters as potential diesel fuel replacements as well as short- and medium-chain volatile esters as fragrance and flavor compounds. These efforts have been limited by the lack of a rapid screen to quantify ester biosynthesis. Enzyme engineering efforts have also been limited by the lack of a high throughput screen for AATase activity. Here, we developed a high throughput assay for AATase activity and used this assay to discover a high activity AATase from tomato fruit, Solanum lycopersicum (Atf-S.l). Atf1-S.l exhibited broad specificity towards acyl-CoAs with chain length from C4 to C10 and was specific towards 1-pentanol. The AATase screen also revealed new acyl-CoA substrate specificities for Atf1, Atf2, Eht1, and Eeb1 from Saccharomyces cerevisiae, and Atf-C.m from melon fruit, Cucumis melo, thus increasing the pool of characterized AATases that can be used in ester biosynthesis of ester-based fragrance and flavor compounds as well as fatty acid ethyl ester biofuels. PMID:26814045

  4. Surface Tension Characteristics of Aqueous Lithium Bromide Solution with Alcoholic Surfactant

    NASA Astrophysics Data System (ADS)

    Sasaki, Naoe; Ogawa, Kiyoshi

    At present, the combination of aqueous lithium bromide (LiBr) solution as an absorbent and water as a refrigerant have widely been used as the working fluid for absorption refrigerating machines. In order to obtain absorption enhancement of water vapor into the LiBr solution by Marangoni convection, an alcoholic surfactant is being added in the LiBr solution. In that case, the surface tension of the LiBr solution with the surfactant plays an important role for the vapor absorption. In this study, the surface tensions of the LiBr solution with several alcoholic surfactants such as 1-butanol, 1-hexanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 1-heptanol, 1-octanol and 2-ethyl-1-hexanol were measured by Wilhelmy plate method. As a result, the surface tensions of 50 wt% LiBr solution with several surfactants were obtained over the LiBr solution temperature range from 298 K to 318 K and the surfactant concentration range from 0 to 104 ppm by mass. The measured surface tension has decreased with the increasing number of carbons included in the surfactant at constant concentration, and the surface tension has increased with the increasing temperature of 50 wt% LiBr solution. The surface tension increase of 1-octanol became greater than any other surfactant used in this work. The effective carbon number of the surfactant for the absorption enhancement was in the range from 7 to 8.

  5. Selective detection of alkanolamine vapors by ion mobility spectrometry with ketone reagent gases.

    PubMed

    Gan, T H; Corino, G

    2000-02-15

    The ion mobility (IMS) spectra of the alkanolamines, monoethanolamine (MEA), 3-amino-1-propanol (PRA), 4-amino-1-butanol (BUA), and 5-amino-1-pentanol (PEA) with acetone and 4-heptanone reagent gases have been measured using a hand-held spectrometer. Monomer and dimer peak patterns were observed for all the alkanolamines with acetone reagent gas. Drift times of monomer and dimer ion clusters for each alkanolamine increased linearly in order of size of alkyl group. Ammonia, Freon 22, and F76 diesel vapors, having similar or coincident mobilities, caused severe interference. Replacement of acetone with 4-heptanone reagent gas resulted in good separation by the altering drift times of product ions. The limit of detection was 0.005 ppm having a linear range of 0.005-0.7 ppm, and signal saturation occurred above 0.88 ppm. Detection was reversible, with a response time of 4 min and a slower recovery time of > 60 min, at vapor levels of 0.7 ppm and ambient nozzle and drift-region temperatures. In contrast to acetone chemistry, single-peak patterns were observed for the alkanolamines with the 4-heptanone reagent. Further, drift times unexpectedly remained stagnant with increasing alkyl-group size. From atmospheric pressure chemical ionization (APcI) tandem mass spectral identifications and collision induced studies, dynamic changes in product-ion equilibria in the IMS drift region compensated by differences in collision cross sections were suggested as the governing causes of the unusual mobility effect. PMID:10701266

  6. Enantiomeric separation of imidazolinone herbicides using chiral high-performance liquid chromatography.

    PubMed

    Lin, Kunde; Xu, Chao; Zhou, Shanshan; Liu, Weiping; Gan, Jay

    2007-03-01

    Chiral high-performance liquid chromatography (HPLC) is one of the most powerful tools to prepare enantiopure standards of chiral compounds. In this study, the enantiomeric separation of imidazolinone herbicides, i.e., imazethapyr, imazapyr, and imazaquin, was investigated using chiral HPLC. The enantioselectivity of Chiralpak AS, Chiralpak AD, Chiralcel OD, and Chiralcel OJ columns for the three analytes was compared under similar chromatographic conditions. Chiralcel OJ column showed the best chiral resolving capacity among the test columns. The resolved enantiomers were distinguished by their signs of circular dichroism detected at 275 nm and their structures confirmed with LC-mass spectrometric analysis. Factors affecting the chiral separation of imidazolinones on Chiralcel OJ column were characterized. Ethanol acted as a better polar modifier than the other alcohols including 2-propanol, 1-butanol, and 1-pentanol. Although the acidic modifier in the mobile phase did not influence chiral recognition, it was necessary for reducing the retention time of enantiomers and suppressing their peak tailing. Thermodynamic evaluation suggests that enantiomeric separation of imidazolinones on Chiralcel OJ column is an enthalpy-driven process from 10 to 40 degrees C. This study also shows that small amounts of pure enantiomers of imidazolinones may be obtained by using the analytical chiral HPLC approach. PMID:17167748

  7. Can volatile organic metabolites be used to simultaneously assess microbial and mite contamination level in cereal grains and coffee beans?

    PubMed

    Salvador, Angelo C; Baptista, Inês; Barros, António S; Gomes, Newton C M; Cunha, Angela; Almeida, Adelaide; Rocha, Silvia M

    2013-01-01

    A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC-ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC-ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans. PMID:23613710

  8. Can Volatile Organic Metabolites Be Used to Simultaneously Assess Microbial and Mite Contamination Level in Cereal Grains and Coffee Beans?

    PubMed Central

    Salvador, Ângelo C.; Baptista, Inês; Barros, António S.; Gomes, Newton C. M.; Cunha, Ângela; Almeida, Adelaide; Rocha, Silvia M.

    2013-01-01

    A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC–ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC–ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans. PMID:23613710

  9. Bacterial Degradation of tert-Amyl Alcohol Proceeds via Hemiterpene 2-Methyl-3-Buten-2-ol by Employing the Tertiary Alcohol Desaturase Function of the Rieske Nonheme Mononuclear Iron Oxygenase MdpJ

    PubMed Central

    Schuster, Judith; Schäfer, Franziska; Hübler, Nora; Brandt, Anne; Rosell, Mònica; Härtig, Claus; Harms, Hauke; Müller, Roland H.

    2012-01-01

    Tertiary alcohols, such as tert-butyl alcohol (TBA) and tert-amyl alcohol (TAA) and higher homologues, are only slowly degraded microbially. The conversion of TBA seems to proceed via hydroxylation to 2-methylpropan-1,2-diol, which is further oxidized to 2-hydroxyisobutyric acid. By analogy, a branched pathway is expected for the degradation of TAA, as this molecule possesses several potential hydroxylation sites. In Aquincola tertiaricarbonis L108 and Methylibium petroleiphilum PM1, a likely candidate catalyst for hydroxylations is the putative tertiary alcohol monooxygenase MdpJ. However, by comparing metabolite accumulations in wild-type strains of L108 and PM1 and in two mdpJ knockout mutants of strain L108, we could clearly show that MdpJ is not hydroxylating TAA to diols but functions as a desaturase, resulting in the formation of the hemiterpene 2-methyl-3-buten-2-ol. The latter is further processed via the hemiterpenes prenol, prenal, and 3-methylcrotonic acid. Likewise, 3-methyl-3-pentanol is degraded via 3-methyl-1-penten-3-ol. Wild-type strain L108 and mdpJ knockout mutants formed isoamylene and isoprene from TAA and 2-methyl-3-buten-2-ol, respectively. It is likely that this dehydratase activity is catalyzed by a not-yet-characterized enzyme postulated for the isomerization of 2-methyl-3-buten-2-ol and prenol. The vitamin requirements of strain L108 growing on TAA and the occurrence of 3-methylcrotonic acid as a metabolite indicate that TAA and hemiterpene degradation are linked with the catabolic route of the amino acid leucine, including an involvement of the biotin-dependent 3-methylcrotonyl coenzyme A (3-methylcrotonyl-CoA) carboxylase LiuBD. Evolutionary aspects of favored desaturase versus hydroxylation pathways for TAA conversion and the possible role of MdpJ in the degradation of higher tertiary alcohols are discussed. PMID:22194447

  10. Chemical communication in Chagas disease vectors. Source, identity, and potential function of volatiles released by the metasternal and Brindley's glands of Triatoma infestans adults.

    PubMed

    Manrique, Gabriel; Vitta, Ana C R; Ferreira, Raquel A; Zani, Carlos L; Unelius, C Rikard; Lazzari, Claudio R; Diotaiuti, Lileia; Lorenzo, Marcelo G

    2006-09-01

    Compounds from the metasternal and Brindley's glands of the blood-sucking bug, Triatoma infestans, were identified by solid phase microextraction (SPME) and gas chromatography-mass spectrometry. Volatile compounds released by adult bugs during copulation or after mechanical disturbance were also characterized. Six compounds were identified and found consistently in all samples from metasternal glands. The most abundant were 3-pentanone, 2-methylbutanol, 3-pentanol, and an unidentified compound. The metasternal gland blends did not differ qualitatively between sexes. Compounds found in Brindley's glands were short chain acids, alcohols, esters, and a ketone with no qualitative differences between sexes. Isobutyric acid was the main component of this blend, and two new confirmed compounds were described as products of these glands: 2-butanone and 2-methylbutyric acid. 3-Pentanone was collected from the headspace over 33% of the copulating pairs of T. infestans. Volatiles found in the headspace of disturbed T. infestans adults included short-chain fatty acids, alcohols, esters, and ketones, with no qualitative differences between sexes. Both types of glands apparently discharge their contents after disturbance. However, most of the volatiles released by bugs after disturbance came from Brindley's glands. The locomotor activity of fourth instars increased significantly after stimulation with the odors emitted by disturbed adults, as compared with larvae stimulated by the odor of undisturbed adults or by clean air. We also studied the directional behavioral response of fifth instars to the disturbance scent in a locomotion compensator. Larvae exposed to volatiles released by disturbed adults walked away from the direction of the odor. The results suggest that this blend or part of it functions as an alarm pheromone for T. infestans. We suggest that the metasternal glands of this species are involved both in the sexual and the alarm contexts, and that the Brindley's glands probably have both alarm and defensive roles. PMID:16902820

  11. Iterative tandem catalysis of secondary diols and diesters to chiral polyesters.

    PubMed

    van As, Bart A C; van Buijtenen, Jeroen; Mes, Tristan; Palmans, Anja R A; Meijer, E W

    2007-01-01

    The well-known dynamic kinetic resolution of secondary alcohols and esters was extended to secondary diols and diesters to afford chiral polyesters. This process is an example of iterative tandem catalysis (ITC), a polymerization method where the concurrent action of two fundamentally different catalysts is required to achieve chain growth. In order to procure chiral polyesters of high enantiomeric excess value (ee) and good molecular weight, the catalysts employed need to be complementary and compatible during the polymerization reaction. We here show that Shvo's catalyst and Novozym 435 fulfil these requirements. The optimal polymerization conditions of 1,1'-(1,3-phenylene) diethanol (1,3-diol) and diisopropyl adipate required 2 mol% Shvo's catalyst and 12 mg Novozym 435 per mmol alcohol group in the presence of 0.5 M 2,4-dimethyl-3-pentanol as the hydrogen donor. With these conditions, chiral polyesters were obtained with peak molecular weights up to 15 kDa, an ee value up to 99% and with 1-3 % ketone end groups. Also with the structural isomer, 1,4-diol, a chiral polyester was obtained, albeit with lower molecular weight (8.3 kDa) and slightly lower ee (94%). Aliphatic secondary diols also resulted in enantio-enriched polymers but at most an ee of 46 % was obtained with molecular weights in the range of 3.3-3.7 kDa. This low ee originates from the intrinsic low enantioselectivity of Novozym 435 for this type of secondary aliphatic diols. The results presented here show that ITC can be applied to procure chiral polyesters with good molecular weight and high ee from optically inactive AA-BB type monomers. PMID:17659517

  12. Topical delivery of hexamidine.

    PubMed

    Parisi, Nicola; Paz-Alvarez, Miguel; Matts, Paul J; Lever, Rebecca; Hadgraft, Jonathan; Lane, Majella E

    2016-06-15

    Hexamidine diisethionate (HEX D) has been used for its biocidal actions in topical preparations since the 1950s. Recent data also suggest that it plays a beneficial role in skin homeostasis. To date, the extent to which this compound penetrates the epidermis has not been reported nor how its topical delivery may be modulated. In the present work we set out to characterise the interaction of HEX D with the skin and to develop a range of simple formulations for topical targeting of the active. A further objective was to compare the skin penetration of HEX D with its corresponding dihydrochloride salt (HEX H) as the latter has more favourable physicochemical properties for skin uptake. Candidate vehicles were evaluated by in vitro Franz cell permeation studies using porcine skin. Initially, neat solvents were investigated and subsequently binary systems were examined. The solvents and chemical penetration enhancers investigated included glycerol, dimethyl isosorbide (DMI), isopropyl alcohol (IPA), 1,2-pentanol (1,2-PENT), polyethylene glycol (PEG) 200, propylene glycol (PG), propylene glycol monolaurate (PGML) and Transcutol(®)P (TC). Of a total of 30 binary solvent systems evaluated only 10 delivered higher amounts of active into the skin compared with the neat solvents. In terms of topical efficacy, formulations containing PGML far surpassed all other solvents or binary combinations. More than 70% of HEX H was extracted from the skin following application in PG:PGML (50:50). Interestingly, the same vehicle effectively promoted skin penetration of HEX D but demonstrated significantly lower uptake into and through the skin (30%). The findings confirm the unpredictable nature of excipients on delivery of actives with reference to skin even where there are minor differences in molecular structures. We also believe that they underline the ongoing necessity for fundamental studies on the interaction of topical excipients with the skin. PMID:27130367

  13. Comparative study of aromatic compounds in fruit wines from raspberry, strawberry, and mulberry in central Shaanxi area

    PubMed Central

    Feng, Yiming; Liu, Min; Ouyang, Yanan; Zhao, Xianfang; Ju, Yanlun; Fang, Yulin

    2015-01-01

    Background Although grape wines have firmly dominated the production and consumption markets of fruit wines, raspberry, strawberry, and mulberry have been utilized to make wines because of their joyful aroma and high contents of polyphenolic phytochemicals and essential fatty acids. However, little is known about aromatic compounds of the wines produced from these three fruits. Methods The aromatic composition of fruit wines produced from raspberry, strawberry, mulberry, and red grape was analyzed by GC-MS. Odor activity values (OAVs) and relative odor contributions (ROCs) were used to estimate the sensory contribution of the aromatic compounds to the overall flavor of the wines. Results In strawberry, raspberry, and mulberry wines, 27, 30, and 31 odorants were detected, respectively. Alcohols formed the most abundant group, followed by esters and acids. The grape wine contained a wider variety (16 types) of alcohols, and 4-methyl-2-pentanol and 2,3-butanediol were not present in the three fruit wines. The quantity of esters in raspberry (1.54%) and mulberry wines (2.08%) were higher than those of strawberry wine (0.78%), and mulberry wine contained more types of esters. There were no significant differences of acids between the three fruit wines and the control wine. In addition, 2-heptanone, 2-octanone, 2-nonanone, and 2-undecanone were unique to raspberry wine, and nonanal was present only in mulberry wine. The indistinguishable aroma of the three fruit wines was attributed to the dominance of fruity and floral odor components derived from ethyl esters of fatty acids and their contributions to the global aroma of the three fruit wines. Conclusion The present study demonstrated that there were significant differences in the volatile components of fruit wines made from raspberry, strawberry, and mulberry. The aroma compounds were more abundant in the raspberry and mulberry wines than in the strawberry wine, but the quality of strawberry wine was superior to raspberry and mulberry wines. PMID:26617387

  14. Kinetic limitations on tracer partitioning in ganglia dominated source zones.

    PubMed

    Ervin, Rhiannon E; Boroumand, Ali; Abriola, Linda M; Ramsburg, C Andrew

    2011-11-01

    Quantification of the relationship between dense nonaqueous phase liquid (DNAPL) source strength, source longevity and spatial distribution is increasingly recognized as important for effective remedial design. Partitioning tracers are one tool that may permit interrogation of DNAPL architecture. Tracer data are commonly analyzed under the assumption of linear, equilibrium partitioning, although the appropriateness of these assumptions has not been fully explored. Here we focus on elucidating the nonlinear and nonequilibrium partitioning behavior of three selected alcohol tracers - 1-pentanol, 1-hexanol and 2-octanol in a series of batch and column experiments. Liquid-liquid equilibria for systems comprising water, TCE and the selected alcohol illustrate the nonlinear distribution of alcohol between the aqueous and organic phases. Complete quantification of these equilibria facilitates delineation of the limits of applicability of the linear partitioning assumption, and assessment of potential inaccuracies associated with measurement of partition coefficients at a single concentration. Column experiments were conducted under conditions of non-equilibrium to evaluate the kinetics of the reversible absorption of the selected tracers in a sandy medium containing a uniform entrapped saturation of TCE-DNAPL. Experimental tracer breakthrough data were used, in conjunction with mathematical models and batch measurements, to evaluate alternative hypotheses for observed deviations from linear equilibrium partitioning behavior. Analyses suggest that, although all tracers accumulate at the TCE-DNAPL/aqueous interface, surface accumulation does not influence transport at concentrations typically employed for tracer tests. Moreover, results reveal that the kinetics of the reversible absorption process are well described using existing mass transfer correlations originally developed to model aqueous boundary layer resistance for pure-component NAPL dissolution. PMID:22115085

  15. Development of a standard gas generating vial comprised of a silicon oil-polystyrene/divinylbenzene composite sorbent.

    PubMed

    Grandy, Jonathan J; Gómez-Ríos, German A; Pawliszyn, Janusz

    2015-09-01

    In this work, a highly reproducible standard gas generating vial is proposed. The vial is comprised of a silicon diffusion pump oil spiked with an appropriate calibration compound, such as modified McReynolds probes (benzene, 2-pentanone, pyridine, 1-nitropropane, 1-pentanol, and n-octane), and then mixed with polystyrene/divinylbenzene (PS/DVB) particles. The concentrations of these compounds in gaseous headspace were found to substantially decrease in comparison to previously developed hydrocarbon pump oil based vials; hence, the amount of standard loaded onto SPME fibers was at most, half that of the previous vial design. Depletion for all compounds after 208 successive extractions was shown to be less than 3.5%. Smaller quantities of standards being used resulted in a vial that depleted slower while remaining statistically repeatable over a wider number of runs. Indeed, it was found that depletion could be largely predicted by using a mass balance theoretical model. This behavior allowed a further increase in the number of loadings that could be performed repeatedly. At a 95% level of confidence, the ANOVA test demonstrated that the prepared vials were statistically identical, with no significant intra- or inter-batch differences. In addition, it was found that vials stored under different conditions (e.g. under light exposure, room temperature, and within a refrigerator) were stable over 10 weeks. Silicon based vials proved to be ideal for performing instrument quality control and loading of internal standards onto fibers, both of which are of great importance when performing on-site analysis using portable GC-MS instrumentation and high throughput determinations in laboratory. PMID:26243704

  16. Volatiles in raw and cooked meat from lambs fed olive cake and linseed.

    PubMed

    Gravador, R S; Serra, A; Luciano, G; Pennisi, P; Vasta, V; Mele, M; Pauselli, M; Priolo, A

    2015-04-01

    This study was conducted to determine the effects of feeding olive cake and linseed to lambs on the volatile organic compounds (VOCs) in raw and cooked meat. Four groups of eight male Appenninica lambs each were fed: conventional cereal-based concentrates (diet C), concentrates containing 20% on a dry matter (DM) basis of rolled linseed (diet L), concentrates containing 35% DM of stoned olive cake (diet OC), or concentrates containing both rolled linseed (10% DM) and stoned olive cake (17% DM; diet OCL). The longissimus dorsi muscle of each lamb was sampled at slaughter and was subjected to VOC profiling through the use of SPME-GC-MS. In the raw meat, the concentration of 3-methylpentanoic acid was higher in treatment C as compared with treatments L, OC and OCL (P<0.01). Moreover the level of nonanoic acid was greater in treatments C and OC than in treatment L (P<0.05). With respect to alcohols, in raw meat the amount of 2-phenoxyethanol in treatment OCL was lower than in treatments C (P<0.01) and OC (P<0.05), while in cooked meat the amount of 1-pentanol was higher in treatment C than in treatment OC (P<0.05). Apart from these compounds, none of the lipid oxidation-derived volatiles was significantly affected by the dietary treatment. Therefore, the results suggest that the replacement of cereal concentrates with linseed and/or olive cake did not cause appreciable changes in the production of volatile organic compounds in lamb meat. PMID:25387868

  17. Determination of volatile compounds in wine by gas chromatography-flame ionization detection: comparison between the U.S. Environmental Protection Agency 3sigma approach and Hubaux-Vos calculation of detection limits using ordinary and bivariate least squares.

    PubMed

    Caruso, Rosario; Scordino, Monica; Traulo, Pasqualino; Gagliano, Giacomo

    2012-01-01

    A capillary GC-flame ionization detection (FID) method to determine volatile compounds (ethyl acetate, 1,1-diethoxyethane, methyl alcohol, 1-propanol, 2-methyl-1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 1-butanol, and 2-butanol) in wine was investigated in terms of calculation of detection limits and calibration method. The main objectives were: (1) calculation of regression coefficient parameters by ordinary least-squares (OLS) and bivariate least-squares (BLS) regression models, taking into account errors in both axes; (2) estimation of linear dynamic range (LDR) according to International Conference on Harmonization recommendations; (3) performance evaluation of a method by using three different internal standards (ISs) such as acetonitrile, acetone, and 1-pentanol; (4) evaluation of LODs according to the U.S. Environmental Protection Agency (EPA) 3sigma approach and the Hubaux-Vos (H-V) method; (5) application of H-V theory to a gas chromatographic analytical method and to a food matrix; and (6) accuracy assessment of the method relative to methyl alcohol content through a Unione Italiana Vini (UIV) interlaboratory proficiency test. Calibration curves calculated via BLS and OLS show similar slopes, while intercepts are closer to zero in the first case, independent of the chosen IS. The studied ISs show a substantially equivalent behavior, even though the IS closer to the analyte retention time seems to be more appropriate in terms of LDR and LOD. Results indicate an underestimation of LODs using the EPA 3sigma approach instead of the more realistic H-V method, both with OLS and BLS regression models. Methanol contents compared with UIV average values indicate recovery between 90 and 110%. PMID:22649934

  18. Isoform selectivity of adenylyl cyclase inhibitors: characterization of known and novel compounds.

    PubMed

    Brand, Cameron S; Hocker, Harrison J; Gorfe, Alemayehu A; Cavasotto, Claudio N; Dessauer, Carmen W

    2013-11-01

    Nine membrane-bound adenylyl cyclase (AC) isoforms catalyze the production of the second messenger cyclic AMP (cAMP) in response to various stimuli. Reduction of AC activity has well documented benefits, including benefits for heart disease and pain. These roles have inspired development of isoform-selective AC inhibitors, a lack of which currently limits exploration of functions and/or treatment of dysfunctions involving AC/cAMP signaling. However, inhibitors described as AC5- or AC1-selective have not been screened against the full panel of AC isoforms. We have measured pharmacological inhibitor profiles for all transmembrane AC isoforms. We found that 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22,536), 2-amino-7-(furanyl)-7,8-dihydro-5(6H)-quinazolinone (NKY80), and adenine 9-?-d-arabinofuranoside (Ara-A), described as supposedly AC5-selective, do not discriminate between AC5 and AC6, whereas the putative AC1-selective inhibitor 5-[[2-(6-amino-9H-purin-9-yl)ethyl]amino]-1-pentanol (NB001) does not directly target AC1 to reduce cAMP levels. A structure-based virtual screen targeting the ATP binding site of AC was used to identify novel chemical structures that show some preference for AC1 or AC2. Mutation of the AC2 forskolin binding pocket does not interfere with inhibition by SQ22,536 or the novel AC2 inhibitor, suggesting binding to the catalytic site. Thus, we show that compounds lacking the adenine chemical signature and targeting the ATP binding site can potentially be used to develop AC isoform-specific inhibitors, and discuss the need to reinterpret literature using AC5/6-selective molecules SQ22,536, NKY80, and Ara-A. PMID:24006339

  19. Isoform Selectivity of Adenylyl Cyclase Inhibitors: Characterization of Known and Novel Compounds

    PubMed Central

    Brand, Cameron S.; Hocker, Harrison J.; Gorfe, Alemayehu A.; Cavasotto, Claudio N.

    2013-01-01

    Nine membrane-bound adenylyl cyclase (AC) isoforms catalyze the production of the second messenger cyclic AMP (cAMP) in response to various stimuli. Reduction of AC activity has well documented benefits, including benefits for heart disease and pain. These roles have inspired development of isoform-selective AC inhibitors, a lack of which currently limits exploration of functions and/or treatment of dysfunctions involving AC/cAMP signaling. However, inhibitors described as AC5- or AC1-selective have not been screened against the full panel of AC isoforms. We have measured pharmacological inhibitor profiles for all transmembrane AC isoforms. We found that 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22,536), 2-amino-7-(furanyl)-7,8-dihydro-5(6H)-quinazolinone (NKY80), and adenine 9-?-d-arabinofuranoside (Ara-A), described as supposedly AC5-selective, do not discriminate between AC5 and AC6, whereas the putative AC1-selective inhibitor 5-?[[2-?(6-?amino-?9H-?purin-?9-?yl)?ethyl]?amino]?-?1-?pentanol (NB001) does not directly target AC1 to reduce cAMP levels. A structure-based virtual screen targeting the ATP binding site of AC was used to identify novel chemical structures that show some preference for AC1 or AC2. Mutation of the AC2 forskolin binding pocket does not interfere with inhibition by SQ22,536 or the novel AC2 inhibitor, suggesting binding to the catalytic site. Thus, we show that compounds lacking the adenine chemical signature and targeting the ATP binding site can potentially be used to develop AC isoformspecific inhibitors, and discuss the need to reinterpret literature using AC5/6-selective molecules SQ22,536, NKY80, and Ara-A. PMID:24006339

  20. Effect of Selected Volatiles on Two Stored Pests: The Fungus Fusarium verticillioides and the Maize Weevil Sithophilus zeamais.

    PubMed

    Zunino, María P; Herrera, Jimena M; Pizzolitto, Romina P; Rubinstein, Héctor R; Zygadlo, Julio A; Dambolena, José S

    2015-09-01

    New agronomic practices and technology enabled Argentina a larger production of cereal grains, reaching a harvest yield of 26.5 million metric tons of maize, of which, about 40% was exported. However, much of the maize production is lost annually by the attack of fungi and insects (2.6 million tons). In this study, the antifungal effect of selected volatiles on Fusarium verticillioides, its mycotoxin production, and the repellent and insecticidal activities against the weevill Sithophilus zeamais, an insect vector of F. verticillioides, were evaluated. The compounds tested were (2E)-2-hexenal, (2E)-2-nonenal, (2E,6Z)-2,6-nonadienal, 1-pentanol, 1-hexanol, 1-butanol, 3-methyl-1-butanol, pentanal, 2-decanone, and 3-decanone, which occur in the blend of volatile compounds emitted by various cereal grains. The most active antifungals were the aldehydes (2E)-2-nonenal, (2E)-2-hexenal, and (2E,6Z)-2,6-nonadienal (minimum inhibitory concentration values of <0.03, 0.06, and 0.06 mM, respectively). The occurrence of fumonisin B1 also was prevented because these compounds completely inhibited fungal growth. The best insecticidal fumigant activities against the maize weevil were shown by 2-decanone and 3-decanone (lethal concentration ≤ 54.6 μL/L (<0.28 mM)). Although, all tested compounds showed repellent activity against S. zeamais at a concentration of 4 μL/L, (2E,6Z)-2,6-nonadienal was the most active repellent compound. These results demonstrate the potential of (2E,6Z)-2,6-nonadienal to be used as a natural alternative to synthetic pesticides on F. verticillioides and S. zeamais. PMID:26257042

  1. Exhalation pattern changes during fasting and low dose glucose treatment in rats.

    PubMed

    Fink, Tobias; Albrecht, Frederic W; Maurer, Felix; Kleber, Astrid; Hüppe, Tobias; Schnauber, Kristina; Wolf, Beate; Baumbach, Jörg I; Volk, Thomas; Kreuer, Sascha

    2015-05-01

    The analysis of exhaled metabolites has become a promising field of research in recent decades. Several volatile organic compounds reflecting metabolic disturbance and nutrition status have even been reported. These are particularly important for long-term measurements, as needed in medical research for detection of disease progression and therapeutic efficacy. In this context, it has become urgent to investigate the effect of fasting and glucose treatment for breath analysis. In the present study, we used a model of ventilated rats that fasted for 12 h prior to the experiment. Ten rats per group were randomly assigned for continuous intravenous infusion without glucose or an infusion including 25 mg glucose per 100 g per hour during an observation period of 12 h. Exhaled gas was analysed using multicapillary column ion-mobility spectrometry. Analytes were identified by the BS-MCC/IMS database (version 1209; B & S Analytik, Dortmund, Germany). Glucose infusion led to a significant increase in blood glucose levels (p < 0.05 at 4 h and thereafter) and cardiac output (p < 0.05 at 4 h and thereafter). During the observation period, 39 peaks were found collectively. There were significant differences between groups in the concentration of ten volatile organic compounds: p < 0.001 at 4 h and thereafter for isoprene, cyclohexanone, acetone, p-cymol, 2-hexanone, phenylacetylene, and one unknown compound, and p < 0.001 at 8 h and thereafter for 1-pentanol, 1-propanol, and 2-heptanol. Our results indicate that for long-term measurement, fasting and the withholding of glucose could contribute to changes of volatile metabolites in exhaled air. PMID:25808025

  2. The effects of electrolysis on operational solutions in electromembrane extraction: The role of acceptor solution.

    PubMed

    Kubáň, Pavel; Boček, Petr

    2015-06-12

    Fundamental operational principle and instrumental set-up of electromembrane extraction (EME) suggest that electrolysis may play an important role in this recently developed micro-extraction technique. In the present study, the effect of electrolysis in EME is described comprehensively for the first time and it is demonstrated that electrolysis considerably influences EME performance. Micro-electromembrane extraction (μ-EME) across free liquid membrane formed by 1-pentanol was utilized for real-time monitoring of the electrolytically induced changes in composition of μ-EME solutions. These changes were visualized with a set of acid-base indicators. Changes in colours of their aqueous solutions revealed serious variations in their pH values, which occurred within seconds to minutes of the μ-EME process. Variations of up to eight pH units were observed for indicator solutions initially prepared in 1, 5 and 10mM hydrochloric acid. No or only negligible pH changes (less than 0.15 pH unit) were observed for indicator solutions prepared in 50 and 100mM acetic acid demonstrating that initial composition of the aqueous solutions was the crucial parameter. These results were also confirmed by theoretical calculations of maximum pH variations in the solutions, which were based on total electric charge transfers measured in the μ-EME systems, and by exact measurements of their pH values after μ-EMEs. Acceptor solutions that, in the current practice, consist predominantly of low concentrations of strong mineral acids or alkali hydroxides may thus not always ensure adequate EME performance, which was manifested by decrease in extraction recoveries of a basic drug papaverine. A suitable remedy to the observed effects is the application of acceptor solutions containing high concentrations of weak acids or bases. These solutions not only eliminate the decrease in recoveries but also serve well as matrices of extracted samples for subsequent analysis by capillary electrophoresis. PMID:25937132

  3. Exhalation of volatile organic compounds during hemorrhagic shock and reperfusion in rats: an exploratory trial.

    PubMed

    Hüppe, Tobias; Lorenz, Dominik; Maurer, Felix; Albrecht, Frederic W; Schnauber, Kristina; Wolf, Beate; Sessler, Daniel I; Volk, Thomas; Fink, Tobias; Kreuer, Sascha

    2016-01-01

    Ischemia and reperfusion alter metabolism. Multi-capillary column ion-mobility spectrometry (MCC-IMS) can identify volatile organic compounds (VOCs) in exhaled gas. We therefore used MCC-IMS to evaluate exhaled gas in a rat model of hemorrhagic shock with reperfusion. Adult male Sprague-Dawley rats (n  =  10 in control group, n  =  15 in intervention group) were anaesthetized and ventilated via tracheostomy for 14 h or until death. Hemorrhagic shock was maintained for 90 min by removing blood from the femoral artery to a target of MAP 35  ±  5 mmHg, and then retransfusing the blood over 60 min in 15 rats; 10 control rats were evaluated without shock and reperfusion. Exhaled gas was analyzed with MCC-IMS, VOCs were identified using the BS-MCC/IMS analytes database (Version 1209). VOC intensities were analyzed at the end of shock, end of reperfusion, and after 9 h. All normotensive animals survived the observation period, whereas mean survival time was 11.2 h in shock and reperfusion animals. 16 VOCs differed significantly for at least one of the three analysis periods. Peak intensities of butanone, 2-ethyl-1-hexanol, nonanal, and an unknown compound were higher in shocked than normotensive rats, and another unknown compound increased over the time. 1-butanol increased only during reperfusion. Acetone, butanal, 1.2-butandiol, isoprene, 3-methylbutanal, 3-pentanone, 2-propanol, and two unknown compounds were lower and decreased during shock and reperfusion. 1-pentanol and 1-propanol were significant greater in the hypotensive animals during shock, were comparable during reperfusion, and then decreased after resuscitation. VOCs differ during hemorrhagic shock, reperfusion, and after reperfusion. MCC-IMS of exhaled breath deserves additional study as a non-invasive approach for monitoring changes in metabolism during ischemia and reperfusion. PMID:26971584

  4. Physicochemical studies of mixed surfactant microemulsions with isopropyl myristate as oil.

    PubMed

    Bardhan, Soumik; Kundu, Kaushik; Saha, Swapan K; Paul, Bidyut K

    2013-07-15

    The present study is focused on evaluation of interfacial compositions and thermodynamic properties of w/o mixed surfactant [(sodium dodecylsulfate, SDS/polyoxyethylene (23) lauryl ether, Brij-35)/1-pentanol (Pn)/isopropyl myristate (IPM)] microemulsions under various physicochemical conditions by the dilution method. The number of moles of Pn at the interface (n(a)(i)) and bulk oil (n(a)(o)), and various thermodynamic parameters [viz. standard Gibbs free energy (ΔG(o→i)(0)), standard enthalpy (ΔH(o→i)(0)), and standard entropy (ΔS(o→i)(0)) of the transfer of Pn from bulk oil to the interface] have been found to be dependent on the molar ratio of water to surfactant (ω), concentration of Brij-35 (X(Brij-35)), and temperature. Temperature-insensitive microemulsions with zero specific heat capacity (ΔC(p)(0))(o→i) have been formed at specific compositions. The intrinsic enthalpy change of the transfer process (ΔH(0))(o→i)* has been evaluated from linear correlation between ΔH(o→i)(0) and ΔS(o→i)(0) at different experimental temperatures. The present report also aims at a precise characterization on the basis of molecular interactions between the constituents and provides insight into the nature of the oil/water interfaces of these systems by conductivity and dynamic light scattering studies as a function of ω and X(Brij-35). Conductivity studies reveal that incorporation of Brij-35 in non-percolating water/SDS/Pn/IPM systems makes them favorable for ω-induced percolation behavior up to X(Brij-35) ≤ 0.5. But further addition of Brij-35 causes a decrease in conductivity with increasing ω. Furthermore, the hydrodynamic diameters of the microemulsion droplets increase with increase in both X(Brij-35) and ω. Correlations of the results in terms of the evaluated physicochemical parameters have been attempted. PMID:23664388

  5. Microfluidic processing of concentrated surfactant mixtures: online SAXS, microscopy and rheology.

    PubMed

    Martin, Hazel P; Brooks, Nicholas J; Seddon, John M; Luckham, Paul F; Terrill, Nick J; Kowalski, Adam J; Cabral, João T

    2016-02-14

    We investigate the effect of microfluidic flow on the microstructure and dynamics of a model surfactant mixture, combining synchrotron Small Angle X-ray Scattering (SAXS), microscopy and rheology. A system comprising a single-chain cationic surfactant, hexadecyl trimethyl ammonium chloride (C16TAC), a short-chain alcohol (1-pentanol) and water was selected for the study due to its flow responsiveness and industrial relevance. Model flow fields, including sequential contraction-expansion (extensional) and rotational flows, were investigated and the fluid response in terms of the lamellar d-spacing, orientation and birefringence was monitored in situ, as well as the recovery processes after cessation of flow. Extensional flows are found to result in considerable d-spacing increase (from approx 59 Å to 65 Å). However, under continuous flow, swelling decreases with increasing flow velocity, eventually approaching the equilibrium values at velocities ≃2 cm s(-1). Through individual constrictions we observe the alignment of lamellae along the flow velocity, accompanied by increasing birefringence, followed by an orientation flip whereby lamellae exit perpendicularly to the flow direction. The resulting microstructures are mapped quantitatively onto the flow field in 2D with 200 μm spatial resolution. Rotational flows alone do not result in appreciable changes in lamellar spacing and flow type and magnitude evidently impact the fluid microstructure under flow, as well as upon relaxation. The findings are correlated with rheological properties measured ex situ to provide a mechanistic understanding of the effect of flow imposed by tubular processing units in the phase behavior and performance of a model surfactant system with ubiquitous applications in personal care and coating industries. PMID:26739043

  6. In Vitro Evaluation of Antimicrobial Efficacy of Extracts Obtained from Raw and Fermented Wild Macrofungus, Lenzites quercina.

    PubMed

    Ogidi, Olusola Clement; Oyetayo, Victor Olusegun; Akinyele, Bamidele Juliet

    2015-01-01

    In recent time, there is a major concern about antibiotic resistance displayed by some pathogenic microorganisms and this had involved a continuous search for natural antimicrobial products. The phytochemistry as well as antimicrobial activity of extracts obtained from Lenzites quercina was investigated. The extracts and purified fractions were, respectively, tested against indicator organisms using agar well diffusion and disc diffusion methods. The quantity of phytochemicals found in the extracts of L. quercina ranged from 14.4 to 20.7 mg/g for alkaloids, 6.1 to 12.8 mg/g for steroids, 4.5 to 10.6 mg/g for saponins, 2.8 to 17.2 mg/g for terpenoids, and 0.41 to 17.1 mg/g for flavonoids. The gas chromatography mass spectrophotometry (GCMS) analysis of the extract reveals the presence of caprylic acid, stearic acid, tetradecanoic acid, methyl-11-octadecenoate, oleic acid, and 4-methyl-2-propyl-1-pentanol. Extracts of L. quercina and its purified fractions exhibited wider range of inhibition (4 mm to 26 mm) on Staphylococcus aureus (ATCC 29213), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 35218), Methicillin Resistant Staphylococcus aureus (MRSA), Salmonella typhi, Bacillus cereus, Enterococcus faecalis, Candida albicans, and Aspergillus niger. The antimicrobial effects of L. quercina extracts indicate that this wild macrofungus contains significant amount of pharmacological agents, which could be extracted to curb the menace of antibiotic resistances by pathogenic organisms. PMID:26604928

  7. In Vitro Evaluation of Antimicrobial Efficacy of Extracts Obtained from Raw and Fermented Wild Macrofungus, Lenzites quercina

    PubMed Central

    Ogidi, Olusola Clement; Oyetayo, Victor Olusegun; Akinyele, Bamidele Juliet

    2015-01-01

    In recent time, there is a major concern about antibiotic resistance displayed by some pathogenic microorganisms and this had involved a continuous search for natural antimicrobial products. The phytochemistry as well as antimicrobial activity of extracts obtained from Lenzites quercina was investigated. The extracts and purified fractions were, respectively, tested against indicator organisms using agar well diffusion and disc diffusion methods. The quantity of phytochemicals found in the extracts of L. quercina ranged from 14.4 to 20.7 mg/g for alkaloids, 6.1 to 12.8 mg/g for steroids, 4.5 to 10.6 mg/g for saponins, 2.8 to 17.2 mg/g for terpenoids, and 0.41 to 17.1 mg/g for flavonoids. The gas chromatography mass spectrophotometry (GCMS) analysis of the extract reveals the presence of caprylic acid, stearic acid, tetradecanoic acid, methyl-11-octadecenoate, oleic acid, and 4-methyl-2-propyl-1-pentanol. Extracts of L. quercina and its purified fractions exhibited wider range of inhibition (4 mm to 26 mm) on Staphylococcus aureus (ATCC 29213), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 35218), Methicillin Resistant Staphylococcus aureus (MRSA), Salmonella typhi, Bacillus cereus, Enterococcus faecalis, Candida albicans, and Aspergillus niger. The antimicrobial effects of L. quercina extracts indicate that this wild macrofungus contains significant amount of pharmacological agents, which could be extracted to curb the menace of antibiotic resistances by pathogenic organisms. PMID:26604928

  8. An examination of the H/D isotope substitution effect on selectivity and activity in the cavitating ultrasound hydrogenation of aqueous 3-buten-2-ol and 1,4-pentadien-3-ol on Pd-black

    SciTech Connect

    Boyles, Kelly R.; Chajkowski, Sarah M.; Disselkamp, Robert S.; Peden, Charles HF

    2006-05-24

    An H/D isotope effect study of the (H2 versus D2) hydrogenation of the aqueous substrates 3-buten-2-ol (3B2OL) and 1,4-pentadien-3-ol (14PD3OL) was performed using Pd-black catalyst. Either H2O or D2O solvents were employed (for alcohol H/D isotope substitution). Two experimental processing conditions of cavitating ultrasound (CUS) and stirred/silent (SS) methods were used. Products formed include 2-butanol and 2-butanone for the former, and 3-pentanol and 3-pentanone for the latter. The observed selectivity and pseudo-first order reaction rate coefficients (e.g., activity) to these products enabled a mechanistic interpretation of the various reaction conditions to be proposed. Experiments utilized a 50 mL batch reactor maintained at 298 K, employed 5.4 atm of H2 or D2 gas, while seven aliquots were collected during the course of the reaction. We have utilized 1-propanol as an inert dopant in all experiments to enable the rapid onset of cavitation in the CUS systems as described earlier [R.S. Disselkamp et al., J. Catal., 227, 552 (2004)]. The following conclusions were noted. First, the activity of the CUS compared to SS processing were ~100-fold larger. Second, variable catalyst loading experiments for stirred/silent D2 hydrogenation processing indicated that mass transfer of hydrogen gas to the Pd-surface played a role such that higher catalyst loading reduced surface D-atom concentrations and reduced saturated alcohol formation (e.g., via reduced H-addition to surface alkyl radicals). Third, for CUS processing the ketone selectivities for experiments employing water compared to D2O indicated that 3B2OL were twice as large, whereas for 14PD3OL they were comparable. This suggests, somewhat surprisingly, that for 3B2OL enol tautomerization to ketone is a slow, and possibly rate-controlling, process. Finally, again for CUS processing, the similarity in ketone selectivities (all ~17%) for H2 compared to D2 hydrogenation for both 3B2OL and 14PD3OL suggest that both H/D isotopes have rapid surface diffusion and hence give rise to nearly equal selectivies. Restated, the thermal or cavitating ultrasound activation is much greater than the surface H/D diffusion barrier.

  9. Sensory and physicochemical evolution of tropical cooked peeled shrimp inoculated by Brochothrix thermosphacta and Lactococcus piscium CNCM I-4031 during storage at 8°C.

    PubMed

    Fall, Papa Abdoulaye; Pilet, Marie France; Leduc, François; Cardinal, Mireille; Duflos, Guillaume; Guérin, Camille; Joffraud, Jean-Jacques; Leroi, Françoise

    2012-01-16

    This study investigated the sensory quality and physicochemical evolution (pH, glucose, l-lactic acid, biogenic amine, free amino-acids and volatile compounds) during storage at 8°C of cooked peeled shrimp inoculated with the specific spoilage bacteria Brochothrix thermosphacta alone or mixed with the protective strain Lactococcus piscium CNCM I-4031. Growth of both bacteria was monitored at regular intervals during storage by microbial counts and the thermal temperature gradient gel electrophoresis (TTGE) technique. Bacterial counts showed that L. piscium and B. thermosphacta inoculated at 7 log CFU/g and 3 log CFU/g were well adapted to shrimp, reaching a maximum level of 9 log CFU/g after 4days and 10days respectively. In mixed culture, the growth of B. thermosphacta was reduced by 3.2±0.1 log CFU/g. The TTGE technique allowed monitoring the colonisation of the strains on the shrimp matrix and confirming the dominance of L. piscium in mixed culture throughout the experiment. Sensory analysis confirmed that B. thermosphacta spoiled the product after 11days, when its cell number attained 8 log CFU/g with the emission of strong butter/caramel off-odours. This sensory profile could be linked to the production of 2,3 butanedione, cyclopentanol, 3-methylbutanol, 3-methylbutanal, 2-methylbutanal, 4-methyl-3-chloro-3-pentanol and ethanol, which were produced in more significant quantities in the B. thermosphacta batch than in the batches in which the protective strain was present. On the contrary, TVBN and TMA were not suitable as quality indicators for B. thermosphacta spoilage activity. In the products where the protective L. piscium strain was present, no adverse effect on sensory quality was noted by the sensory panels. Moreover, biogenic amine assessment did not show any histamine or tyramine production by this strain, underlining its safety profile. Both strains produced lactic acid (1850mg/kg in L. piscium and B. thermosphacta batch on days 3 and 10 respectively; 3830mg/kg on day 7 in mixed culture) and the pH decrease from 6.6±0.0 to 5.9±0.1 was similar in all batches. Lactic acid production or competition for free amino-acid was not involved in the inhibition mechanism; however rapid glucose consumption by L. piscium could partially explain the growth limitation of the spoilage micro-organism. This study demonstrated the spoilage characteristic of B. thermosphacta and the usefulness of L. piscium as a bioprotective culture for tropical cooked peeled shrimp without any adverse effect on the sensory quality of the product. PMID:21835482

  10. Organic compound composition in soil and sediments collected in Jackson, Mississippi.

    PubMed

    Gołębiowski, Marek; Stepnowski, Piotr; Hemmingway, Tometrick; Leszczyńska, Danuta

    2016-06-01

    The aim of our study was to identify organic pollutants found in soil and sediment samples collected within the Jackson, MS metropolitan area. The chemical characterization of the organic compound fractions in soil and sediment samples was carried out by separating the organic fraction using column chromatography (CC) and quantitatively analyzing the polycyclic aromatic hydrocarbons (PAHs), n-alkanes and other organic compounds using gas chromatography-electron impact mass spectrometry (GC-MS). Fifty-six compounds were identified and quantified in the soil samples and 33 compounds were identified and quantified in the sediment samples. The PAHs, n-alkanes and other organic compound profiles in the soil and sediment samples were compared. The percentage contents of the organic compounds in the soil samples were very diverse (from traces to 12.44 ± 1.47%). The compounds present in the highest concentrations were n-alkanes: n-C31 (12.44 ± 1.47%), n-C29 (11.64 ± 1.21%), and n-C33 (8.95 ± 1.08%). The components occurring in smaller quantities (from 1% to 5%) were 2 PAHs (fluoranthene 1.28 ± 0.25%, pyrene 1.16 ± 0.20%), 10 n-alkanes from n-C21 (1.25 ± 0.29%) to n-C32 (2.67 ± 0.52%) and 11 other compounds (e.g., 2-pentanol, 4-methyl (3.33 ± 0.44%), benzyl butyl phthalate (4.25 ± 0.59%), benzenedicarboxylic acid (1.14 ± 0.08%), ethane, 1,1-diethoxy (3.15 ± 0.41) and hexadecanoic acid (2.52 ± 0.34). The soil samples also contained 30 compounds present in concentrations <1% (e.g., anthracene (0.13 ± 0.04%), n-C20 (0.84 ± 0.21%) and acetic acid (0.12 ± 0.04%). The compounds present in the highest concentrations in the sediment samples were PAHs: pyrene (7.73 ± 1.15%) and fluoranthene (6.23 ± 1.07%) and n-alkanes: n-C31 (6.74 ± 1.21%), n-C29 (6.65 ± 0.98%) and n-C27 (6.13 ± 1.09%). The remaining organic compounds were present in smaller quantities (< 5%). PMID:26943144

  11. Airborne molds and bacteria, microbial volatile organic compounds (MVOC), plasticizers and formaldehyde in dwellings in three North European cities in relation to sick building syndrome (SBS).

    PubMed

    Sahlberg, Bo; Gunnbjörnsdottir, Maria; Soon, Argo; Jogi, Rain; Gislason, Thorarinn; Wieslander, Gunilla; Janson, Christer; Norback, Dan

    2013-02-01

    There are few studies on associations between airborne microbial exposure, formaldehyde, plasticizers in dwellings and the symptoms compatible with the sick building syndrome (SBS). As a follow-up of the European Community Respiratory Health Survey (ECRHS II), indoor measurements were performed in homes in three North European cities. The aim was to examine whether volatile organic compounds of possible microbial origin (MVOCs), and airborne levels of bacteria, molds, formaldehyde, and two plasticizers in dwellings were associated with the prevalence of SBS, and to study associations between MVOCs and reports on dampness and mold. The study included homes from three centers included in ECRHS II. A total of 159 adults (57% females) participated (19% from Reykjavik, 40% from Uppsala, and 41% from Tartu). A random sample and additional homes with a history of dampness were included. Exposure measurements were performed in the 159 homes of the participants. MVOCs were analyzed by GCMS with selective ion monitoring (SIM). Symptoms were reported in a standardized questionnaire. Associations were analyzed by multiple logistic regression. In total 30.8% reported any SBS (20% mucosal, 10% general, and 8% dermal symptoms) and 41% of the homes had a history of dampness and molds There were positive associations between any SBS and levels of 2-pentanol (P=0.002), 2-hexanone (P=0.0002), 2-pentylfuran (P=0.009), 1-octen-3-ol (P=0.002), formaldehyde (P=0.05), and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (Texanol) (P=0.05). 1-octen-3-ol (P=0.009) and 3-methylfuran (P=0.002) were associated with mucosal symptoms. In dwellings with dampness and molds, the levels of total bacteria (P=0.02), total mold (P=0.04), viable mold (P=0.02), 3-methylfuran (P=0.008) and ethyl-isobutyrate (P=0.02) were higher. In conclusion, some MVOCs like 1-octen-3-ol, formaldehyde and the plasticizer Texanol, may be a risk factor for sick building syndrome. Moreover, concentrations of airborne molds, bacteria and some other MVOCs were slightly higher in homes with reported dampness and mold. PMID:23280302

  12. Involvement of reversible binding to alpha 2u-globulin in 1,4-dichlorobenzene-induced nephrotoxicity.

    PubMed

    Charbonneau, M; Strasser, J; Lock, E A; Turner, M J; Swenberg, J A

    1989-06-01

    Similarly to unleaded gasoline, 1,4-dichlorobenzene (1,4-DCB) administered for 2 years caused a dose-related increase in the incidence of renal tumors in male but not in female rats or in either sex of mice. Unleaded gasoline and 2,2,4-trimethylpentane (TMP), a component of unleaded gasoline, increased protein droplet formation and cell proliferation in male but not in female rat kidneys. These protein droplets contained, alpha 2u-globulin, a male rat-specific low-molecular-weight protein and 2,4,4-trimethyl-2-pentanol, a metabolite of TMP that was reversibly bound to this protein. Studies were undertaken to determine if 1,4-DCB produced similar effects; 1,2-DCB was used for comparison since it did not produce renal carcinogenesis in male rats. Gel filtration chromatography of a 116,000g supernatant prepared from kidneys of 1,4-[14C]DCB-treated rats showed that radiolabel coeluted with alpha 2u-globulin as one sharp peak as opposed to a multipeak pattern observed for 1,2-[14C]DCB; the maximal quantity of radiolabel for 1,4-DCB was twice that for 1,2-DCB. Equilibrium dialysis of kidney cytosol in the presence or absence of sodium dodecyl sulfate demonstrated that the radiolabel was reversibly bound to alpha 2u-globulin; the amount for 1,4-[14C]DCB-treated rats was almost twice as much as that for 1,2-[14C]DCB-treated rats. 1,2-DCB was also shown to be covalently bound to renal alpha 2u-globulin, and covalently bound to liver and plasma high-molecular-weight proteins. 1,4-DCB and, to a minor extent, 2,5-dichlorophenol, the major metabolite of 1,4-DCB, were reversibly bound to renal alpha 2u-globulin from 1,4-DCB-treated rats. 1,4-DCB increased protein droplet formation in male but not in female rat kidneys, whereas equimolar doses of 1,2-DCB showed no effect in either sex. Renal cell proliferation, measured by [3H]thymidine incorporation into renal DNA, was increased after 1,4-DCB but not after 1,2-DCB treatment. Nephrotoxicity and biochemical alterations induced by 1,4-DCB resemble those of unleaded gasoline and suggest that a similar mechanism is involved in the induction of alpha 2u-globulin nephropathy in male rats. PMID:2471290

  13. 2,2,4-Trimethylpentane-induced nephrotoxicity. II. The reversible binding of a TMP metabolite to a renal protein fraction containing alpha 2u-globulin.

    PubMed

    Lock, E A; Charbonneau, M; Strasser, J; Swenberg, J A; Bus, J S

    1987-11-01

    Trimethylpentane (TMP) produces nephrotoxicity in male but not in female rats. The toxicity is characterized by an increase in protein droplets in proximal convoluted tubular cells and an increase in the renal concentration of the male-rat-specific protein alpha 2u-globulin. Subcellular fractionation of the kidneys from male rats 24 hr after [3H]TMP administration showed that about 60% of the radiolabeled material was localized in the 116,000g supernatant. Column chromatography of this supernatant resolved the radioactivity into two components; one, which contained about 26% of the radiolabel, coeluted with alpha 2u-globulin and cross-reacted with an antibody specific for alpha 2u-globulin. The remaining component eluted in the low-molecular-weight range (less than 1000 Da) and was assumed to be TMP metabolites. Radiolabel from [3H]TMP in male rat urine also resolved into two components with about 0.1% of the radiolabel in urine coeluting with the alpha 2u-globulin-containing fraction. Radiolabel from TMP in male rat liver 116,000g supernatant and plasma and in female rat kidney 116,000g supernatant eluted as a single component in the low-molecular-weight range. Dialysis (1000-Da cutoff) of male kidney 116,000g supernatant led to a loss of the low-molecular-weight components, but nondialyzable radiolabel (about 20%) still coeluted with the alpha 2u-globulin after gel chromatography. Dialysis against 0.1% sodium dodecyl sulfate led to a loss of both the low- and high-molecular-weight radioactive material. These results suggested that the high-molecular-weight radioactive material was formed by the reversible binding of a radioactive component of TMP to a male-rat-specific protein. Gas chromatography-mass spectrometry of an ethyl acetate extract of the alpha 2u-globulin-containing fractions of TMP-treated male rat kidney 116,000g supernatant identified 2,4,4-trimethyl-2-pentanol as the only bound metabolite to alpha 2u-globulin. These studies provide the first evidence for a reversible binding between a metabolite of TMP and a male-rat-specific protein in the kidney and thus provide important insight delineating a potential mechanism of hydrocarbon-induced hyaline-droplet nephropathy. PMID:2445051

  14. Correlation between hydrophobicity of short-chain aliphatic alcohols and their ability to alter plasma membrane integrity.

    PubMed

    McKarns, S C; Hansch, C; Caldwell, W S; Morgan, W T; Moore, S K; Doolittle, D J

    1997-03-01

    The quantitative relationship between chemical structure and biological activity has received considerable attention in the fields of pharmacology and drug development. More recently, quantitative structure-activity relationships (QSARs) have been used for predicting chemical toxicity. It has been proposed that alcohols may elicit their toxic effects through hydrophobic interactions with the cellular membrane. The objective of this study was to evaluate the role of hydrophobicity in the loss of membrane integrity following acute exposure to short-chain aliphatic alcohols in rat liver epithelial cells in vitro. The series of alcohols studied included methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-butanol, 2-methyl-1-propanol, and 2-methyl-2-propanol. The lactate dehydrogenase (LDH) assay was used to quantify membrane integrity. The logarithm of the octanol/water partition coefficient (log P) was used to quantify hydrophobicity. LDH50 values, representing alcohol concentrations yielding a 50% increase in LDH release relative to untreated controls (i.e., mild disruption of membrane integrity), and EC50 values, representing alcohol concentrations yielding 50% of the maximal release of LDH (i.e., moderate disruption of LDH release), were experimentally determined for each alcohol. The LDH50 and EC50 values were then used to derive the QSAR relationship. The aqueous alcohol concentrations yielding LDH50 or EC50 values ranged from 8.9 x 10(-4) m (LDH50 for octanol) to 3.5 m (EC50 for methanol), and the log P of the alcohols ranged from -0.77 (methanol) to 3.00 (octanol). From these data, we have derived two QSAR equations describing the role of hydrophobicity in the release of LDH from rat liver epithelial cells following a 1-hr alcohol exposure. The QSAR equation for LDH50 values, log (1/LDH50) = 0.896 log P + 0.117 (n = 11, SD = 0.131), was nearly identical to the QSAR equation for EC50 values, log (1/EC50) = 0.893 log P + 0.101 (n = 11, SD = 0.133], suggesting that similar structure-activity relationships exist at both mild and moderate levels of membrane disruption. Our data indicate that an increase in LDH release was positively and linearly correlated with the hydrophobicity (r = 0.993). These data may help predict the potential biological effects of other, as yet untested, aliphatic alcohols and aliphatic alcohol-like compounds (e.g., anesthetics) on the plasma membrane. PMID:9073468

  15. Milk volatile organic compounds and fatty acid profile in cows fed timothy as hay, pasture, or silage.

    PubMed

    Villeneuve, M-P; Lebeuf, Y; Gervais, R; Tremblay, G F; Vuillemard, J C; Fortin, J; Chouinard, P Y

    2013-01-01

    Nutrient composition and organoleptic properties of milk can be influenced by cow diets. The objective of this study was to evaluate the forage type effects on volatile organic compounds, fatty acid (FA) profile, and organoleptic properties of milk. Timothy grass was fed as hay, pasture, or silage during a period of 27 d to a group of 21 cows in a complete block design based on days in milk. Each cow also received 7.2 kg/d of a concentrate mix to meet their nutrient requirements. Forage dry matter intake averaged 13.9 kg/d and was not different among treatments. Milk yield was higher for cows fed pasture, intermediate for cows fed silage, and lowest for cows fed hay. However, milk fat content was higher for cows fed hay and silage, compared with cows fed pasture. As a result, fat-corrected milk and fat yield were not different among treatments. Increasing the supply of dietary cis-9,cis-12 18:2 (linoleic acid) and cis-9,cis-12,cis-15 18:3 (?-linolenic acid) when feeding pasture enhanced the concentration of these 2 essential FA in milk fat compared with feeding hay or silage. Moreover, the ratio of 16:0 (palmitic acid) to cis-9 18:1 (oleic acid), which is closely related to the melting properties of milk fat, was lower in milk from cows on pasture than in milk from cows fed hay or silage. Cows fed hay produced milk with higher levels of several free FA and ?-lactones, but less pentanal and 1-pentanol. More dimethyl sulfone and toluene were found in milk of cows on pasture. Cows fed silage produced milk with higher levels of acetone, 2-butanone, and ?-pinene. Results from a sensory evaluation showed that panelists could not detect a difference in flavor between milk from cows fed hay compared with silage. However, a significant number of assessors perceived a difference between milk from cows fed hay compared with milk from cows fed pasture. In a sensory ranking test, the percentage of assessors ranking for the intensity of total (raw milk, fresh milk, and farm milk), sweet (empyreumatic, vanilla, caramel, and sugar), and grassy (grass, leafy vegetable, and plant) flavors was higher for milk from cows fed pasture compared with hay and silage. Using timothy hay, pasture, or silage harvested at a similar stage of development, the current study shows that the taste of milk is affected by the forage type fed to cows. More research is, however, needed to establish a link between the sensory attributes of milk and the observed changes in volatile organic compounds and FA profile. PMID:24035021

  16. An efficient and general route to reduced polypropionates via Zr-catalyzed asymmetric C—C bond formation

    PubMed Central

    Negishi, Ei-ichi; Tan, Ze; Liang, Bo; Novak, Tibor

    2004-01-01

    An efficient and general method for the synthesis of reduced polypropionates has been developed through the application of asymmetric carboalumination of alkenes catalyzed by dichlorobis(1-neomenthylindenyl)zirconium [(NMI)2ZrCl2]. In this investigation, attention has been focused on those reduced polypropionates that are α-monoheterofunctional and either ω-ethyl or ω-n-propyl. The reaction of 3-buten-1-ol with triethylaluminum (Et3Al) or tripropylaluminum (nPr3Al) in the presence of (NMI)2ZrCl2 and isobutylaluminoxane gave, after protonolysis, (R)-3-methyl-1-pentanol as well as (R)- and (S)-3-methyl-1-hexanols in 88–92% yield in 90–92% enantiomeric excess in one step. These 3-monomethyl-1-alkanols were then converted to two stereoisomers each of 2,4-dimethyl-1-hexanols and 2,4-dimethyl-1-heptanols via methylalumination catalyzed by (NMI)2ZrCl2 and methylaluminoxane followed by oxidation with O2. The four-step (or three-isolation-step) protocol provided syn-2,4-dimethyl-1-alkanols of ≥98% stereoisomeric purity in ≈50% overall yields, whereas (2S,4R)-2,4-dimethyl-1-hexanol of comparable purity was obtained in 40% overall yield. Commercial availability of (S)-2-methyl-1-butanol as a relatively inexpensive material suggested its use in the synthesis of (2S,4S)- and (2R,4S)-2,4-dimethyl-1-hexanols via a three-step protocol consisting of (i) iodination, (ii) zincation followed by Pd-catalyzed vinylation, and (iii) Zr-catalyzed methylalumination followed by oxidation with O2. This three-step protocol is iterative and applicable to the synthesis of reduced polypropionates containing three or more branching methyl groups, rendering this method for the synthesis of reduced polypropionates generally applicable. Its synthetic utility has been demonstrated by preparing the side chain of zaragozic acid A and the C11–C20 fragment of antibiotics TMC-151 A–F. PMID:15073327

  17. The Effect of Cavitating Ultrasound on the Aqueous Phase Hydrogenation of Cis-2-buten-1-ol and Cis-2-penten-1-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Denslow, Kayte M.; Hart, Todd R.; White, James F.; Peden, Charles HF.

    2005-07-15

    We have studied the effect of cavitating ultrasound on the heterogeneous aqueous hydrogenation of cis-2-buten-1-ol (C4 olefin) and cis-2-penten-1-ol (C5 olefin) on Pd-black to form the trans-olefins (trans-2-buten-1-ol and trans-2-penten-1-ol) and saturated alcohols (1-butanol and 1-pentanol, respectively). Silent (and magnetically stirred) experiments served as control experiments. As described in an earlier publication by our group, we have added an inert dopant, 1-propanol, in the reaction mixture to ensure the rapid onset of cavitation in the ultrasound-assisted reactions that can lead to altered selectivity compared to silent reaction systems [Disselkamp et al., J. Catal., 227 (2004) 552]. The motivation for this study is to examine whether cavitating ultrasound can reduce the [trans-olefin/saturated alcohol] molar ratio during the course of the reaction. This could have practical application in that it may offer an alternative processing methodology of synthesizing healthier edible seed oils by reducing trans-fat content. We have observed that cavitating ultrasound results in a [(trans-olefin/saturated alcohol)ultrasound/(trans-olefin/saturated alcohol)silent] ratio quantity less than 0.5 at the reaction mid-point for both the C4 and C5 olefin systems. This indicates that ultrasound reduces trans-olefin production compared to the silent control experiment. Furthermore, there is an added 30% reduction for the C5 versus C4 olefin compounds again at reaction mid-point. We attribute differences in the ratio quantity as a moment of inertia effect. In principle, the C4 versus C5 olefins has a {approx}52% increase in moment of inertia about C2=C3 double bond slowing isomerization. Since seed oils are C18 multiple cis olefins and have an moment of inertia even greater than our C5 olefin here, our study suggests that even a greater reduction in trans-olefin content may occur for partial hydrogenation of C18 seed oils.

  18. The effect of cavitating ultrasound on the aqueous phase hydrogenation of cis-2-buten-1-ol and cis-2-penten-1-ol on Pd-black

    SciTech Connect

    Disselkamp, Robert S.; Denslow, Kayte M.; Hart, Todd R.; White, James F.; Peden, Charles HF.

    2005-07-15

    We have studied the effect of cavitating ultrasound on the heterogeneous aqueous hydrogenation of cis-2-buten-1-ol (C4 olefin) and cis-2-penten-1-ol (C5 olefin) on Pd-black to form the trans-olefins (trans-2-buten-1-ol and trans-2-penten-1-ol) and saturated alcohols (1-butanol and 1-pentanol, respectively). Silent (and magnetically stirred) experiments served as control experiments. As described in an earlier publication by our group, we have added an inert dopant, 1-propanol, in the reaction mixture to ensure the rapid onset of cavitation in the ultrasound-assisted reactions that can lead to altered selectivity compared to silent reaction systems [R.S. Disselkamp, Ya-Huei Chin, C.H.F. Peden, J. Catal. 227 (2004) 552]. The motivation for this study is to examine whether cavitating ultrasound can reduce the [trans-olefin/saturated alcohol] molar ratio during the course of the reaction. This could have practical application in that it may offer an alternative processing methodology of synthesizing healthier edible seed oils by reducing trans-fat content.We have observed that cavitating ultrasound results in a [(trans-olefin/saturated alcohol)ultrasound/(trans-olefin/saturated alcohol)silent] ratio quantity less than 0.5 at the reaction mid-point for both the C4 and C5 olefin systems. This indicates that ultrasound reduces trans-olefin production compared to the silent control experiment. Furthermore, there is an added 30% reduction for the C5 versus C4 olefin compounds again at reaction mid-point. We attribute differences in the ratio quantity as a moment of inertia effect. In principle, the C4 versus C5 olefins has a {approx}52% increase in moment of inertia about C2 C3 double bond slowing isomerization. Since seed oils are C18 multiple cis-olefins and have a moment of inertia even greater than our C5 olefin here, our study suggests that even a greater reduction in trans-olefin content may occur for partial hydrogenation of C18 seed oils.

  19. Experimental study of the effect of test-well arrangement for partitioning interwell tracer test on the estimation of NAPL saturation

    NASA Astrophysics Data System (ADS)

    Kim, B.; Kim, Y.; Yeo, I.; Yongcheol Kim, In Wook Yeo

    2011-12-01

    Partitioning interwell tracer test (PITT) is a method to quantify and qualify a contaminated site with NAPLs through a degree of retardation of partitioning tracers compared to a conservative one. Although PITT is known to be a more effective method to measure the saturation of spatially-distributed NAPL contaminant than the point investigation method, the saturation estimation from PITT is reported to be underestimated due to various factors including heterogeneity of the media, adsorption, source zone NAPL architecture, and long tailing in breakthrough curves of partitioning tracers. Analytical description of PITT assumes that the injection-pumping well pair is on the line of ambient groundwater flow direction, but the test-well pair could easily be off the line in the field site, which could be another erroneous factor in analyzing PITT data. The purpose of this work is to study the influence of the angle of the test-well pair to ambient groundwater flow direction based on the result from PITT. The experiments were conducted in a small-scale 3D sandbox with dimensions of 0.5 m × 0.4 m × 0.15 m (LWH) of stainless steel. The surface is covered and sealed with a plexiglass plate to make the physical model a confined aquifer. Eight full-screened wells of Teflon material were installed along the perimeter of a 50 mm circle with 45 degree intervals in the middle of the physical model. Both ends of the sand box are connected to constant head reservoirs. The physical model was wet-packed with sieved and washed sand. Trichloroethylene (TCE) and bromide were used as the contaminant and the conservative tracer, respectively. Hexanol, 2,4-dimethyl-3-pentanol and 6-methyl-2-heptanol were used as partitioning tracers. Before the injection of TCE, a PITT was conducted to measure adsorption coefficient of partitioning tracers to the sand material. TCE of 4.5 mL, dyed with Sudan IV, was injected into the inner part of the circle of the wells. PITTs using the test-well pair parallel and with angles of 45 and 90 degrees to ambient flow direction were performed. Another PITT was conducted at an increased pumping rate with the test-well pair at a 45 degree angle to examine the effect of pumping rate. From the experiments, it was found that as the angles of the test-well pair to ambient groundwater flow direction increased, the estimated NAPL saturation decreased. Although the increase in pumping rate in this experiment reduces the effect of the obliqueness of the test-well arrangement, the effect of rate-limited transfer of partitioning tracers due to the increased pumping rate on the PITT should be examined in the interpretation. The results of these experiments revealed that the arrangement of the test-well pair is another controlling factor in performing and interpreting PITT in the field, in addition to the factors such as heterogeneity, source zone architecture, and tailing. Key words: PITT, test-well arrangement, ambient groundwater flow direction, NAPL saturation Acknowledgements: This research was supported by the Basic Research Project of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Knowledge Economy of Korea. 11-3414

  20. Influence of Mass Transfer Kinetics on Interpretation of Push-Pull Partitioning Tracer Tests

    NASA Astrophysics Data System (ADS)

    Ervin, R. E.; Boroumand, A.; Abriola, L. M.; Ramsburg, C. A.

    2012-12-01

    There is now considerable interest in predicting plume response to various levels of treatment applied within a DNAPL source zone. An important component to the development of this predictive capability is the ability to characterize the distribution of DNAPL within the source zone. Metrics developed for description of source zone architecture are frequently based upon some combination of downgradient contaminant concentrations and in source testing. One option for in source testing is the use of partition tracers in either interwell or push-pull test configurations. Push-pull tracer tests are advantageous for obtaining more localized information that can be integrated with other observations to reduce the uncertainty related the links between the architecture of a source and its associated plume. Here we examined push-pull tracer tests in a series of aquifer cell experiments to evaluate the potential of this type of test to quantify metrics of the DNAPL distribution at the local-scale (i.e., 1 m flow path). Three DNAPL architectures were characterized by conducting push-pull tracer tests using a solution which comprised three partitioning tracers (1-pentanol, 1-hexanol, and 2-octanol) and one non-partitioning tracer (bromide). Each architecture was characterized using three flow regimes that employed combinations of fast (~30 cm/hr) and slow (~2 cm/hr) velocities. Production curves (i.e., tracer concentrations during the pull phase of the test) for the partitioning tracers were found to be asymmetric. This asymmetry severely degraded the ability of an analytical solution employing the local equilibrium assumption to predict the overall saturations. Saturation estimates from the analytical solution were found to be improved when the application of the model was restricted to later time data (Vext/Vinj >1). This observation suggests it is important to better understand the factors influencing the early time data. Experiments were also simulated using a numerical model containing a linear driving force expression to describe the tracer mass transfer. Mass transfer coefficients in all simulations were produced using available correlations for pool dissolution. Perfect knowledge of the DNAPL and permeability distributions, as well as relative permeability effects enabled the numerical model to better capture the asymmetry observed in the production curves. We then began to systematically simplify the numerical model to explore which assumptions associated with the analytical solution cause its poor performance. These assumptions include: uniform packing distribution, uniform DNAPL distribution, equilibrium partitioning, and no permeability reduction due to the presence of the DNAPL. Results suggest only limited degradation in model performance when the medium permeability and DNAPL saturation are assumed to be uniform, and relative permeability effects are neglected. In contrast, model performance was considerably poorer when mass transfer kinetics were neglected. These results highlight the importance of including mass transfer kinetics when characterizing local-scale DNAPL architecture.

  1. A Unique Equation to Estimate Flash Points of Selected Pure Liquids Application to the Correction of Probably Erroneous Flash Point Values

    NASA Astrophysics Data System (ADS)

    Catoire, Laurent; Naudet, Valérie

    2004-12-01

    A simple empirical equation is presented for the estimation of closed-cup flash points for pure organic liquids. Data needed for the estimation of a flash point (FP) are the normal boiling point (Teb), the standard enthalpy of vaporization at 298.15 K [ΔvapH°(298.15 K)] of the compound, and the number of carbon atoms (n) in the molecule. The bounds for this equation are: -100⩽FP(°C)⩽+200; 250⩽Teb(K)⩽650; 20⩽Δvap H°(298.15 K)/(kJ mol-1)⩽110; 1⩽n⩽21. Compared to other methods (empirical equations, structural group contribution methods, and neural network quantitative structure-property relationships), this simple equation is shown to predict accurately the flash points for a variety of compounds, whatever their chemical groups (monofunctional compounds and polyfunctional compounds) and whatever their structure (linear, branched, cyclic). The same equation is shown to be valid for hydrocarbons, organic nitrogen compounds, organic oxygen compounds, organic sulfur compounds, organic halogen compounds, and organic silicone compounds. It seems that the flash points of organic deuterium compounds, organic tin compounds, organic nickel compounds, organic phosphorus compounds, organic boron compounds, and organic germanium compounds can also be predicted accurately by this equation. A mean absolute deviation of about 3 °C, a standard deviation of about 2 °C, and a maximum absolute deviation of 10 °C are obtained when predictions are compared to experimental data for more than 600 compounds. For all these compounds, the absolute deviation is equal or lower than the reproductibility expected at a 95% confidence level for closed-cup flash point measurement. This estimation technique has its limitations concerning the polyhalogenated compounds for which the equation should be used with caution. The mean absolute deviation and maximum absolute deviation observed and the fact that the equation provides unbiaised predictions lead to the conclusion that several flash points have been reported erroneously, whatever the reason, in one or several reference compilations. In the following lists, the currently accepted flash points for bold compounds err, or probably err, on the hazardous side by at least 10 °C and for the nonbolded compounds, the currently accepted flash points err, or probably err, on the nonhazardous side by at least 10 °C: bicyclohexyl, sec-butylamine, tert-butylamine, 2-cyclohexen-1-one, ethanethiol, 1,3-cyclohexadiene, 1,4-pentadiene, methyl formate, acetonitrile, cinnamaldehyde, 1-pentanol, diethylene glycol, diethyl fumarate, diethyl phthalate, trimethylamine, dimethylamine, 1,6-hexanediol, propylamine, methanethiol, ethylamine, bromoethane, 1-bromopropane, tert-butylbenzene, 1-chloro-2-methylpropane, diacetone alcohol, diethanolamine, 2-ethylbutanal, and formic acid. For some other compounds, no other data than the currently accepted flash points are available. Therefore, it cannot be assessed that these flash point data are erroneous but it can be stated that they are probably erroneous. At least, they need experimental re-examination. They are probably erroneous by at least 15 °C: 1,3-cyclopentadiene, di-tert-butyl sulfide, dimethyl ether, dipropyl ether, 4-heptanone, bis(2-chloroethyl)ether, 1-decanol, 1-phenyl-1-butanone, furan, ethylcyclopentane, 1-heptanethiol, 2,5-hexanediol, 3-hexanone, hexanoic acid methyl ester, 4-methyl-1,3-pentadiene, propanoyl chloride, tetramethylsilane, thiacyclopentane, 1-chloro-2-methyl-1-propene, trans-1,3-pentadiene, 2,3-dimethylheptane, triethylenetetramine, methylal, N-ethylisopropylamine, 3-methyl-2-pentene, and 2,3-dimethyl-1-butene.

  2. Decontamination of Tritiated-Water Using Super-hydrophobic Pt-Catalyst Synthesized with Water-in-Supercritical CO{sub 2}

    SciTech Connect

    Youichi Enokida; Kayo Sawada |; Ryosuke Shimizu; Ichiro Yamamoto

    2008-01-15

    Tritium, {sup 3}H, is one of the hydrogen isotopes, created in coolant of a fission reactor and to be utilized as fuel for nuclear fusion reactors. Since a large amount of tritium will be contained in a fusion reactor or in a fission reactor, a small fraction of the tritiated chemical species, in most cases, tritiated water, may leak to the environment. Tritium is, however, a radioactive isotope whose specific radioactivity is 4 x 10{sup 17} Bq kg{sup -1}, and easy to transfer in human body, its confinement is very important from the safety aspect. One of the problems of tritium confinement and decontamination of tritiated chemical species is related with necessity of its isotope separation from lighter hydrogen isotopes, {sup 2}H and {sup 1}H. Most of principles for the isotope separations are based on fractionations of isotopes in different chemical species. A large fractionation for hydrogen isotopes is observed in a chemical exchange of hydrogen atoms between water, Q{sub 2}O, and hydrogen gas, Q{sub 2}, where 'Q' denotes one of the hydrogen isotopes. Heavier isotopes are enriched significantly into Q{sub 2}O rather than Q{sub 2}. Therefore practical method of tritium removal would be established by hydrogen isotope separation with chemical exchange of water and hydrogen gas. At first, we prepared a catalyst, by reducing Pt{sup 4+} in reversed micelles where the reducing agent, aqueous solution of sodium tetra borohydrate, NaBH{sub 4} was also contained in reversed micelles prepared separately. In this situation, micelles containing Pt{sup 4+} and reducing reagent collided and produced Pt nanoparticles, which were expected to be impregnated in the hydrophobic structure after depressurization. After this type of earlier experiment we determined a mass of impregnated Pt by total dissolution of gauze with aqua regia followed by concentration measurement of Pt with ICP-AES. We performed several trials, unfortunately, however, the mass of Pt deposited on the gauze was very small to detect, and this approach turns to be not successful. As the second approach, we utilize CO{sub 2} soluble Pt precursor, CODMe{sub 2}Pt purchased from Sigma-Aldrich Co. and H{sub 2} gas as reducing agent, which could be completely mixed with SC-CO{sub 2}. This system was well-known for Pt particle formation by auto-catalytic growth. The second approach was aiming at increasing Pt amount deposited in the gauze. This approach was successful in increasing Pt amount, but the Pt particle size also increased to be more than 50 nm, which was not suitable for catalyst. Finally, we synthesized the catalyst by the following procedure: firstly, a reducing agent of NaBH{sub 4} was deposited on the nano-textured hydrophobic layer on the gauze. This step was realized by forming reversed micelles of aqueous NaBH{sub 4} solution using a surfactant AOT and a co-surfactant 2,2,3,3,4,4,5,5,-octafluoro-1-pentanol (F-pentanol) in SC-CO{sub 2}. This system of surfactant combination of AOT and F-pentanol has been found to work successfully in recent studies. In the second step, the gauze was contacted with CODMe{sub 2}Pt dissolved in SC-CO{sub 2} to synthesize seeds of Pt particles for the auto-catalytic reaction proceeding by CODMe{sub 2}Pt with hydrogen. The seeds were formed by the reaction between deposited NaBH{sub 4} and CODMe{sub 2}Pt in SC-CO{sub 2}. The physical characterization of this catalyst was performed by SEM-EDS. By this procedure, the Pt hydrophobic catalyst where Pt nanoparticle of 10 nm in diameter was locally deposited in the nano-textured layer was successfully prepared. Hydrophobicity after the chemical Pt deposition was tested by measurement of water absorbed on the gauze and the catalyst performance was evaluated by {sup 1}H{sup 2}H formation through the scrambling reaction from {sup 1}H{sub 2} and {sup 2}H{sub 2} and the reaction was successfully observed. We demonstrated a new hydrophobic catalyst preparation using SC-CO{sub 2} effectively. We can conclude that the approach of creating Pt nanoparticles in SC-CO{sub 2} and depositing them in the super-hydrophobic structure on the metal surface is useful for synthesizing hydrophilic catalysts for the hydrogen isotope separation.