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Sample records for adipate ester contents

  1. Analysis of Adipate Ester Contents in PVC Plastics

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    2006-01-01

    Plasticizers are needed in flexible PVC (PolyVinylChloride) products. There is serious concern that commonly used phthalate esters may harm life reproduction systems. To avoid the problems, instead adipate di-esters (AEs) of C8 to C10 alcohols are used as higher prized alternatives; e.g. di-2......-ethylhexyl adipate or DEHA [103-23-1], also known as Adimoll® or di-octyl adipate, DOA, see Fig. 1. A widely used plasticizer in food (cling) films is DEHA, often in combination with polymers, epoxidized soya-bean oil, etcetera. DEHA also occurs in children toys. We have previously shown that the presence...... of phthalate esters in PVC can be rapidly analyzed by Fourier transform (FT-) Raman spectroscopy excited with a 1064 nm laser. Here in this project we report a similar study. The aim was to find out whether FT-Raman spectroscopy can be used to determine the presence of adipate esters (AEs) as plasticizers...

  2. ANALYSIS OF ADIPATE ESTER CONTENTS IN POLY(VINYL CHLORIDE) PLASTICS

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Otero, Amalia Dopazo

    2006-01-01

    Fourier transform (FT-) Raman spectroscopy excited with a 1064 nm laser can be used to determine the content of plasticizers in commercial flexible poly vinyl chloride (PVC) products. Our previous study [T. Nørbygaard, R.W. Berg, Analysis of phthalate ester content in PVC plastics by means of FT......-Raman Spectroscopy, Appl. Spectrosc. 58 (4) (2004) 410–413]—on detection of the presence of phthalate esters in PVC by FT-Raman spectroscopy — is here extended to the similar case of adipate esters (AEs) in samples of soft poly vinyl chloride plastics. Spectra of a range of adipate ester plasticizers (11 AEs......) in pure form are reported. We studied if qualitative and quantitative determination of the adipate ester content would be possible based on the use of proper reference samples. It was found that AEs as a group cannot be definitively identified by their characteristic Raman bands because other aliphatic...

  3. Poly(glycerol adipate)-fatty acid esters as versatile nanocarriers

    DEFF Research Database (Denmark)

    Weiss, Verena M; Naolou, Toufik; Hause, Gerd

    2012-01-01

    Poly(glycerol adipate) (PGA) is a biodegradable polymer with promising features for nanoparticulate drug carrier systems. By acylation of PGA with fatty acids, composite systems with amphiphilic properties can be obtained. Variation of the fatty acid (laurate, stearate and behenate) and their sub...... and the nanoparticles. With their diverse particle shapes and internal structures as well as their different thermal behavior, aggregate states and polarities, the systems offer promising possibilities as delivery systems for lipophilic, amphiphilic and water soluble drugs.......Poly(glycerol adipate) (PGA) is a biodegradable polymer with promising features for nanoparticulate drug carrier systems. By acylation of PGA with fatty acids, composite systems with amphiphilic properties can be obtained. Variation of the fatty acid (laurate, stearate and behenate...

  4. Analysis of Polyadipate Ester Content in PVC Plastics by Means of FT-Raman Spectroscopy

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    2006-01-01

    Plasticizers are needed in flexible PVC (PolyVinylChloride) products. There is serious concern that commonly used phthalate esters may harm life reproduction systems. To avoid the problems, instead adipate di-esters (AEs) of C8 to C10 alcohols are used as higher prized alternatives; e.g. di-2......-ethylhexyl adipate or DEHA [103-23-1], also known as Adimoll or di-octyl adipate, DOA. A widely used plasticizer in food (cling) films is DEHA, often in combination with polymers, epoxidized soya-bean oil, etcetera. DEHA also occurs in children toys. We have previously shown that the presence of phthalate...... esters in PVC can be rapidly analyzed by Fourier transform (FT-) Raman spectroscopy excited with a 1064 nm laser. Here in this project we report a similar study. The aim was to find out whether FT-Raman spectroscopy can be used to determine the presence of adipate esters (AEs) as plasticizers...

  5. Development of dispersive liquid-liquid microextraction technique using ternary solvents mixture followed by heating for the rapid and sensitive analysis of phthalate esters and di(2-ethylhexyl) adipate.

    Science.gov (United States)

    Farajzadeh, Mir Ali; Khoshmaram, Leila

    2015-01-30

    In this study, for the first time, a dispersive liquid-liquid microextraction technique using a ternary solvent mixture is reported. In order to extract five phthalate esters and di(2-ethylhexyl) adipate with different polarities from aqueous samples, a simplex centroid experimental design method was used to select an optimal mixture of ternary solvents prior to gas chromatographyflame ionization detection. In this work, dimethyl formamide as a disperser solvent containing dichloromethane, chloroform, and carbon tetrachloride as a ternary extraction solvent mixture is injected into sample solution and a cloudy solution is formed. After centrifuging, 250μL of the obtained sedimented phase was transferred into another tube and 5μL DMF was added to it. Then, the tube was heated in a water bath at 75°C for 5min in order to evaporate the main portion of the extraction solvents. Finally, 2μL of the remained phase is injected into the separation system. Under the optimum extraction conditions, the method shows wide linear ranges and low limits of detection and quantification between 0.03-0.15 and 0.09-0.55μgL(-1), respectively. Enrichment factors and extraction recoveries are in the ranges of 980-4500 and 20-90%, respectively. The method is successfully applied in the determination of the target analytes in mineral water, soda, lemon juice, vinegar, dough, and yogurt packed in plastic packages. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Poly(ester-anhydride):poly(beta-amino ester) micro- and nanospheres: DNA encapsulation and cellular transfection.

    Science.gov (United States)

    Pfeifer, Blaine A; Burdick, Jason A; Little, Steve R; Langer, Robert

    2005-11-04

    Poly(ester-anhydride) delivery devices allow flexibility regarding carrier dimensions (micro- versus nanospheres), degradation rate (anhydride versus ester hydrolysis), and surface labeling (through the anhydride functional unit), and were therefore tested for DNA encapsulation and transfection of a macrophage P388D1 cell line. Poly(l-lactic acid-co-sebacic anhydride) and poly(l-lactic acid-co-adipic anhydride) were synthesized through melt condensation, mixed with 25 wt.% poly(beta-amino ester), and formulated with plasmid DNA (encoding firefly luciferase) into micro- and nanospheres using a double emulsion/solvent evaporation technique. The micro- and nanospheres were then characterized (size, morphology, zeta potential, DNA release) and assayed for DNA encapsulation and cellular transfection over a range of poly(ester-anhydride) copolymer ratios. Poly(ester-anhydride):poly(beta-amino ester) composite microspheres (6-12 microm) and nanospheres (449-1031 nm), generated with copolymers containing between 0 and 25% total polyanhydride content, encapsulated plasmid DNA (>or=20% encapsulation efficiency). Within this polyanhydride range, poly(adipic anhydride) copolymers provided DNA encapsulation at an increased anhydride content (10%, microspheres; 10-25%, nanospheres) compared to poly(sebacic anhydride) copolymers (1%, microspheres and nanospheres) with cellular transfection correlating with the observed DNA encapsulation.

  7. Influence of low contents of superhydrophilic MWCNT on the properties and cell viability of electrospun poly (butylene adipate-co-terephthalate) fibers

    International Nuclear Information System (INIS)

    Rodrigues, Bruno V.M.; Silva, Aline S.; Melo, Gabriela F.S.; Vasconscellos, Luana M.R.; Marciano, Fernanda R.; Lobo, Anderson O.

    2016-01-01

    The use of poly (butylene adipate-co-terephthalate) (PBAT) in tissue engineering, more specifically in bone regeneration, has been underexplored to date due to its poor mechanical resistance. In order to overcome this drawback, this investigation presents an approach into the preparation of electrospun nanocomposite fibers from PBAT and low contents of superhydrophilic multi-walled carbon nanotubes (sMWCNT) (0.1–0.5 wt.%) as reinforcing agent. We employed a wide range of characterization techniques to evaluate the properties of the resulting electrospun nanocomposites, including Field Emission Scanning Electronic Microscopy (FE-SEM), Transmission Electronic Microscopy (TEM), tensile tests, contact angle measurements (CA) and biological assays. FE-SEM micrographs showed that while the addition of sMWCNT increased the presence of beads on the electrospun fibers' surfaces, the increase of the neat charge density due to their presence reduced the fibers' average diameter. The tensile test results pointed that sMWCNT acted as reinforcement in the PBAT electrospun matrix, enhancing its tensile strength (from 1.3 to 3.6 MPa with addition of 0.5 wt.% of sMWCNT) and leading to stiffer materials (lower elongation at break). An evaluation using MG63 cells revealed cell attachment into the biomaterials and that all samples were viable for biomedical applications, once no cytotoxic effect was observed. MG-63 cells osteogenic differentiation, measured by ALP activity, showed that mineralized nodules formation was increased in PBAT/0.5%CNTs when compared to control group (cells). This investigation demonstrated a feasible novel approach for producing electrospun nanocomposites from PBAT and sMWCNT with enhanced mechanical properties and adequate cell viability levels, which allows for a wide range of biomedical applications for these materials. - Highlights: • Nanocomposites from PBAT and superhydrophilic MWCNT (sMWCNT) were successfully prepared by electrospinning

  8. 21 CFR 582.1009 - Adipic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Adipic acid. 582.1009 Section 582.1009 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1009 Adipic acid. (a) Product. Adipic acid. (b) [Reserved] (c) Limitations, restrictions, or...

  9. The effect of starch amylose content on the morphology andproperties of melt-processed butyl-etherified starch/poly[(butylenesuccinate)-co-adipate] blends

    CSIR Research Space (South Africa)

    Maubane, Lesego T

    2017-01-01

    Full Text Available structures. Thermogravimetric analysis revealed that the thermal stability of the blends decreased with increasing starch loading for all starch types with varying amylose content; however, the nature of the starch controlled the mechanical properties...

  10. QTL for phytosterol and sinapate ester content in Brassica napus L. collocate with the two erucic acid genes

    Science.gov (United States)

    Amar, Samija; Ecke, Wolfgang; Becker, Heiko C.

    2008-01-01

    Improving oil and protein quality for food and feed purposes is an important goal in rapeseed (Brassica napus L.) breeding programs. Rapeseed contains phytosterols, used to enrich food products, and sinapate esters, which are limiting the utilization of rapeseed proteins in the feed industry. Increasing the phytosterol content of oil and lowering sinapate ester content of meal could increase the value of the oilseed rape crop. The objective of the present study was to identify quantitative trait loci (QTL) for phytosterol and sinapate ester content in a winter rapeseed population of 148 doubled haploid lines, previously found to have a large variation for these two traits. This population also segregated for the two erucic acid genes. A close negative correlation was found between erucic acid and phytosterol content (Spearman’s rank correlation, rs = −0.80**). For total phytosterol content, three QTL were detected, explaining 60% of the genetic variance. The two QTL with the strongest additive effects were mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. For sinapate ester content four QTL were detected, explaining 53% of the genetic variance. Again, a close negative correlation was found between erucic acid and sinapate ester content (rs = −0.66**) and the QTL with the strongest additive effects mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. The results suggests, that there is a pleiotropic effect of the two erucic acid genes on phytosterol and sinapate ester content; the effect of the alleles for low erucic acid content is to increase phytosterol and sinapate ester content. Possible reasons for this are discussed based on known biosynthetic pathways. Electronic supplementary material The online version of this article (doi:10.1007/s00122-008-0734-2) contains supplementary material, which is available to authorized users. PMID:18335203

  11. Fat content affects bioaccessibility and efficiency of enzymatic hydrolysis of lutein esters added to milk and yogurt

    OpenAIRE

    Xavier, Ana Augusta Odorissi; Mercadante, Adriana Zerlotti; Garrido-Fernández, Juan; Pérez-Gálvez, Antonio

    2014-01-01

    © 2014 Elsevier Ltd. Addition of lutein to dairy products is an alternative that widens the range of foods which could be lutein sources. However, bioaccessibility is an essential aspect to be considered during the development of products with added bioactive substances. We evaluated the in vitro bioaccessibility of lutein esters added to milk and yogurt with different fat contents, and determined the efficiency of enzymatic hydrolysis of the esters during digestion. Bioaccessibility of lutei...

  12. How 'ground-picked' olive fruits affect virgin olive oil ethanol content, ethyl esters and quality.

    Science.gov (United States)

    Beltran, Gabriel; Sánchez, Raquel; Sánchez-Ortiz, Araceli; Aguilera, Maria P; Bejaoui, Mohamed A; Jimenez, Antonio

    2016-08-01

    Olives dropped on the ground naturally sometimes are not separated from those fresh and healthy collected from the tree for harvest and processing. In this work we compared the quality, ethanol content and bioactive components of virgin olive oils from ground-picked olives, tree-picked fruits and their mixture. Ground-picked olives produced 'Lampante' virgin olive oils; these are of a lower quality category, because of important alterations in chemical and sensory characteristics. Ethyl esters showed the highest values, although under the regulated limit. The mixture of ground and tree-picked olives gave oils classified as 'virgin' because of sensory defects, although the quality parameters did not exceed the limits for the 'extra' category. Ethanol content showed a significant increase in the oils from ground- picked olives and their mixture with respect to those from tree-picked fruits. Furthermore, bioactive compounds showed a significant decrease as fruit quality was poorer. Ground-picked olives must be harvested and processed separately since they produce low-quality virgin olive oils with sensory defects and lower concentrations of bioactive compounds. The higher acidity and ethanol concentration observed in oils from ground-picked fruits or their mixture may help ethyl ester synthesis during storage. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  13. Overview of MIT, ADIP irradiation experiments

    International Nuclear Information System (INIS)

    Kohse, G.; Harling, O.K.; Grant, N.J.

    1985-06-01

    Various rapidly solidified austenitic, ferritic and copper alloys have been produced at MIT for inclusion in ADIP neutron irradiation experiments. A brief summary of the alloys and their preparation and the achieved or projected irradiation parameters is provided

  14. Effect of milling on DSC thermogram of excipient adipic acid.

    Science.gov (United States)

    Ng, Wai Kiong; Kwek, Jin Wang; Yuen, Aaron; Tan, Chin Lee; Tan, Reginald

    2010-03-01

    The purpose of this research was to investigate why and how mechanical milling results in an unexpected shift in differential scanning calorimetry (DSC) measured fusion enthalpy (Delta(fus)H) and melting point (T(m)) of adipic acid, a pharmaceutical excipient. Hyper differential scanning calorimetry (hyper-DSC) was used to characterize adipic acid before and after ball-milling. An experimental study was conducted to evaluate previous postulations such as electrostatic charging using the Faraday cage method, crystallinity loss using powder X-ray diffraction (PXRD), thermal annealing using DSC, impurities removal using thermal gravimetric analysis (TGA) and Karl Fischer titration. DSC thermograms showed that after milling, the values of Delta(fus)H and T(m) were increased by approximately 9% and 5 K, respectively. Previous suggestions of increased electrostatic attraction, change in particle size distribution, and thermal annealing during measurements did not explain the differences. Instead, theoretical analysis and experimental findings suggested that the residual solvent (water) plays a key role. Water entrapped as inclusions inside adipic acid during solution crystallization was partially evaporated by localized heating at the cleaved surfaces during milling. The correlation between the removal of water and melting properties measured was shown via drying and crystallization experiments. These findings show that milling can reduce residual solvent content and causes a shift in DSC results.

  15. 78 FR 33748 - Diisopropyl Adipate; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2013-06-05

    ... from 1,500 mg/kg to 8,800 mg/ kg. In the guinea pig, the acute oral toxicity of diisopropyl adipate is... adipate, adipic acid, dipropyl adipate or diisobutyl adipate. In a 5 week study, guinea pigs that were... document applies to them. Potentially affected entities may include: Crop production (NAICS code 111...

  16. Determination of Alkyl Esters Content in PDO Extra Virgin Olive Oils from Sicily

    Directory of Open Access Journals (Sweden)

    Rosaria Costa

    2017-01-01

    Full Text Available The quality parameter of alkyl esters of fatty acids was checked in a variety of Italian olive oil samples. In particular, 34 samples of extra virgin olive oils (EVOOs from South Italy (Sicilian orchards, produced in the years 2014-2015, have been subjected to the analytical protocol dictated by the European Union for the determination of alkyl esters, as an indicator of oil’s quality. All the samples analyzed resulted to be well below the limit set by EU Directive. Besides recently produced EVOOs, a set of very aged oils, produced in the years 1996–2000, were analyzed as well. The main finding was that alkyl esters increased in correspondence with deterioration processes.

  17. Production and Characterization of Ethyl Ester from Crude Jatropha curcas Oil having High Free Fatty Acid Content

    Science.gov (United States)

    Kumar, Rajneesh; Dixit, Anoop; Singh, Shashi Kumar; Singh, Gursahib; Sachdeva, Monica

    2015-09-01

    The two step process was carried out to produce biodiesel from crude Jatropha curcas oil. The pretreatment process was carried out to reduce the free fatty acid content by (≤2 %) acid catalyzed esterification. The optimum reaction conditions for esterification were reported to be 5 % H2SO4, 20 % ethanol and 1 h reaction time at temperature of 65 °C. The pretreatment process reduced the free fatty acid of oil from 7 to 1.85 %. In second process, alkali catalysed transesterification of pretreated oil was carried and the effects of the varying concentrations of KOH and ethanol: oil ratios on percent ester recovery were investigated. The optimum reaction conditions for transesterification were reported to be 3 % KOH (w/v of oil) and 30 % (v/v) ethanol: oil ratio and reaction time 2 h at 65 °C. The maximum percent recovery of ethyl ester was reported to be 60.33 %.

  18. Analysis of Phthalate Ester Content in PVC Plastics by means of FT-Raman Spectroscopy

    DEFF Research Database (Denmark)

    Nørbygaard, Thomas; Berg, Rolf W.

    2004-01-01

    Polyvinyl chloride, PVC or [CH2-CHCl]n , is a common polymer used extensively for a wide range of industrial and household products. To achieve the proper material characteristics (e.g. softness, ductility), plasticizers such as phthalates are usually added to the otherwise hard and brittle PVC......, medical devices and toys may harm the e.g. reproductive organs of exposed infants. PVC is readily distinguished from other common polymers (e.g. polyethylene, polypropylene, polystyrene) by the use of Raman spectroscopy. By far the most commonly used phthalate plasticizer in PVC is di(2-ethylhexyl......-phenyl group, and as the relative intensities of the six bands vary only slightly from one phthalate ester to the next one we have obtained an identifiable, characteristic fingerprint of the phthalate ester group as a whole. By use of the set of six bands, which are common to all the measured Raman spectra, we...

  19. Influence of adipic acid on tensile and morphology properties of linear low density polyethylene/rambutan peels flour blends

    Science.gov (United States)

    Nadhirah, A. A.; Sam, S. T.; Noriman, N. Z.; Ragunathan, S.; Ismail, H.

    2015-07-01

    This study investigate about the tensile and morphological properties of degradable polymer produced from linear low density polyethylene/rambutan peel flour (LLDPE/RPF) blends and adipic acid (AA) was used as a compatibilizer by varying the rambutan peel flour (RPF) amount from 0-25wt%. The samples were subjected to tensile and morphological tests. AA compatibilized showed higher strength compared to uncompatibilized blends. The Young's modulus for LLDPE/RPF blends increased with increasing flour content. However, the addition of adipic acid had reduced the Young's Modulus.

  20. Effect of addition of lignin in physical-chemical properties of a polyesters based on glycerol, phthalic and adipic acids

    International Nuclear Information System (INIS)

    Guimaraes, D.H.; Viana, A.P.M.; Lima, A.S.C.; Goncalves, A.P.B.; Miranda, C.S.; Jose, N.M.

    2014-01-01

    In this paper the study of different addition amounts of lignin in the physicochemical properties of polyesters made from glycerol and different amounts of phthalic and adipic acids have been proposed. The following characterizations were made: XRD, FTIR, TGA, DSC and SEM. The variation in the percentage of adipic and phthalic acids had a direct effect on thermal and morphological properties. The thermal analysis showed that there was miscibility between the polyester and lignin, by means of displacement related to the temperature of thermal degradation events. In FTIR analysis was noted displacements of characteristic bands of hydrogen bonds and specific carbonyl ester groups. These shifts were more pronounced as it has larger amounts of phthalic acid as monomer and larger amounts of lignin in the compositions. (author)

  1. CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

    Directory of Open Access Journals (Sweden)

    S. S. Hings

    2008-07-01

    Full Text Available Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (dm<150 nm initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (dcore≤102 nm, the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold.

  2. Computer Aided Synthesis of Innovative Processes: Renewable Adipic Acid Production

    DEFF Research Database (Denmark)

    Rosengarta, Alessandro; Bertran, Maria-Ona; Manenti, Flavio

    2017-01-01

    A promising biotechnological route for the production of adipic acid from renewables has been evaluated, applying a systematic methodology for process network synthesis and optimization. The method allows organizing in a structured database the available knowledge from different sources (prelimin...

  3. Phorbol esters seed content and distribution in Latin American provenances of Jatropha curcas L.: potential for biopesticide, food and feed.

    Science.gov (United States)

    Bueso, Francisco; Sosa, Italo; Chun, Roldan; Pineda, Renan

    2016-01-01

    Jatropha curcas L. (Jatropha) is believed to have originated from Mexico and Central America. So far, characterization efforts have focused on Asia, Africa and Mexico. Non-toxic, low phorbol ester (PE) varieties have been found only in Mexico. Differences in PE content in seeds and its structural components, crude oil and cake from Jatropha provenances cultivated in Central and South America were evaluated. Seeds were dehulled, and kernels were separated into tegmen, cotyledons and embryo for PE quantitation by RP-HPLC. Crude oil and cake PE content was also measured. No phenotypic departures in seed size and structure were observed among Jatropha cultivated in Central and South America compared to provenances from Mexico, Asia and Africa. Cotyledons comprised 96.2-97.5 %, tegmen 1.6-2.4 % and embryo represented 0.9-1.4 % of dehulled kernel. Total PE content of all nine provenances categorized them as toxic. Significant differences in kernel PE content were observed among provenances from Mexico, Central and South America (P 95 % of PEs concentrated in cotyledons, 0.5-3 % in the tegmen and 0.5-1 % in the embryo. Over 60 % of total PE in dehulled kernels accumulated in the crude oil, while 35-40 % remained in the cake after extraction. Low phenotypic variability in seed physical, structural traits and PE content was observed among provenances from Latin America. Very high-PE provenances with potential as biopesticide were found in Central America. No PE-free, edible Jatropha was found among provenances currently cultivated in Central America and Brazil that could be used for human consumption and feedstock. Furthermore, dehulled kernel structural parts as well as its crude oil and cake contained toxic PE levels.

  4. Analysis of seed phorbol-ester and curcin content together with genetic diversity in multiple provenances of Jatropha curcas L. from Madagascar and Mexico.

    Science.gov (United States)

    He, Wei; King, Andrew J; Khan, M Awais; Cuevas, Jesús A; Ramiaramanana, Danièle; Graham, Ian A

    2011-10-01

    Jatropha curcas L. has been promoted as an oilseed crop for use to meet the increased world demand for vegetable oil production, and in particular, as a feedstock for biodiesel production. Seed meal is a protein-rich by-product of vegetable oil extraction, which can either be used as an organic fertilizer, or converted to animal feed. However, conversion of J. curcas seed meal into animal feed is complicated by the presence of toxins, though plants producing "edible" or "non-toxic" seeds occur in Mexico. Toxins present in the seeds of J. curcas include phorbol esters and a type-I ribosome inactivating protein (curcin). Although the edible seeds of J. curcas are known to lack phorbol esters, the curcin content of these seeds has not previously been studied. We analyzed the phorbol ester and curcin content of J. curcas seeds obtained from Mexico and Madagascar, and conclude that while phorbol esters are lacking in edible seeds, both types contain curcin. We also analyzed spatial distribution of these toxins in seeds. Phorbol-esters were most concentrated in the tegmen. Curcin was found in both the endosperm and tegmen. We conclude that seed toxicity in J. curcas is likely to be due to a monogenic trait, which may be under maternal control. We also conducted AFLP analysis and conclude that genetic diversity is very limited in the Madagascan collection compared to the Mexican collection. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  5. Improving the Organoleptic Properties of a Craft Mezcal Beverage by Increasing Fatty Acid Ethyl Ester Contents through ATF1 Expression in an Engineered Kluyveromyces marxianus UMPe-1 Yeast.

    Science.gov (United States)

    Campos-García, Jesús; Vargas, Alejandra; Farías-Rosales, Lorena; Miranda, Ana L; Meza-Carmen, Víctor; Díaz-Pérez, Alma L

    2018-05-02

    Mezcal, a traditional beverage that originated in Mexico, is produced from species of the Agavaceae family. The esters associated with the yeasts utilized during fermentation are important for improving the organoleptic properties of the beverage. We improved the ester contents in a mezcal beverage by using the yeast Kluyveromyces marxianus, which was engineered with the ATF1 gene. ATF1 expression in the recombinant yeast significantly increased compared with that in the parental yeast, but its fermentative parameters were unchanged. Volatile-organic-compound-content analysis showed that esters had significantly increased in the mezcal produced with the engineered yeast. In a sensory-panel test, 48% of the panelists preferred the mezcal produced from the engineered yeast, 30% preferred the mezcal produced from the wild type, and 15 and 7% preferred the two mezcal types produced following the routine procedure. Correlation analysis showed that the fruitiness/sweetness description of the mezcal produced using the ATF1-engineered K. marxianus yeast correlated with the content of the esters, whose presence improved the organoleptic properties of the craft mezcal beverage.

  6. Analysis of phthalate ester content in poly(vinyl chloride) plastics by means of Fourier transform Raman spectroscopy

    DEFF Research Database (Denmark)

    Nørbygaard, Thomas; Berg, Rolf W.

    2004-01-01

    Fourier transform (FT) Raman spectroscopy is applied to a range of phthalate ester plasticizers in pure form as well as in poly(vinyl chloride) (PVC) samples. It is found that phthalate esters as a group can be identified by a set of six characteristic Raman bands. FT-Raman spectra of 22 phthalate...

  7. New Glucopyranosylglyceryl-N-Octenyl Adipate and Bioactivity of ...

    African Journals Online (AJOL)

    1-(3-β-D-Glucopyranosylglycer-2-yl)-6-N-(oct-2-enyl)-adipate, [orientalin, 1] was isolated as a new metabolite from the polar leaf extracts of Toussaintia orientalis Verdc (Annonaceae), together with the glycoflavonoids afzelin and quercitrin, and the indolidinoids toussaintines A-C. The reversed chalcones 2-hydroxy-3,4 ...

  8. Biocatalytic production of adipic acid from glucose using engineered Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Kaushik Raj

    2018-06-01

    Full Text Available Adipic acid is an important industrial chemical used in the synthesis of nylon-6,6. The commercial synthesis of adipic acid uses petroleum-derived benzene and releases significant quantities of greenhouse gases. Biocatalytic production of adipic acid from renewable feedstocks could potentially reduce the environmental damage and eliminate the need for fossil fuel precursors. Recently, we have demonstrated the first enzymatic hydrogenation of muconic acid to adipic acid using microbial enoate reductases (ERs - complex iron-sulfur and flavin containing enzymes. In this work, we successfully expressed the Bacillus coagulans ER in a Saccharomyces cerevisiae strain producing muconic acid and developed a three-stage fermentation process enabling the synthesis of adipic acid from glucose. The ability to express active ERs and significant acid tolerance of S. cerevisiae highlight the applicability of the developed yeast strain for the biocatalytic production of adipic acid from renewable feedstocks. Keywords: Biosynthesis, Renewable resources, Yeast, Adipic acid, Synthetic biology

  9. Amended final report of the safety assessment of dibutyl adipate as used in cosmetics.

    Science.gov (United States)

    Andersen, Alan

    2006-01-01

    Dibutyl Adipate, the diester of butyl alcohol and adipic acid, functions as a plasticizer, skin-conditioning agent, and solvent in cosmetic formulations. It is reportedly used at a concentration of 5% in nail polish and 8% in suntan gels, creams, and liquids. Dibutyl Adipate is soluble in organic solvents, but practically insoluble in water. Dibutyl Adipate does not absorb radiation in the ultraviolet (UV) region of the spectrum. Dibutyl Adipate is not toxic in acute oral or dermal animal toxicity tests. In a subchronic dermal toxicity study, 1.0 ml/kg day-1 caused a significant reduction in body weight gain in rabbits, but 0.5 ml/kg/day1 was without effect. In a study with dogs, no adverse effects were observed when an emulsion containing 6.25% Dibutyl Adipate was applied to the entire body twice a week for 3 months. Dibutyl Adipate was tested for dermal irritation using rabbits and mice and a none to minimal irritation was observed. Dibutyl Adipate at a concentration of 25% was not a sensitizer in a guinea pig maximization study. Undiluted Dibutyl Adipate was minimally irritating to the eyes of rabbits and 0.1% was nonirritating. A significant increase in fetal gross abnormalities was observed in rats given intraperitoneal injections of Dibutyl Adipate at 1.75 ml/kg on 3 separate days during gestation, but no effect was seen in animals given 1.05 ml/kg. Dibutyl Adipate was not genotoxic in either bacterial or mammalian test systems. Clinical patch tests confirmed the absence of skin irritation found in animal tests. Clinical phototoxicity tests were negative. Dibutyl Adipate at 0.1% was not an ocular irritant in two male volunteers. In a clinical test of comedogenicity, Dibutyl Adipate produced no effect. The Cosmetic Ingredient Review (CIR) Expert Panel recognized that use of Dibutyl Adipate in suntan cosmetic products will result in repeated, frequent exposure in a leave-on product. The available data demonstrate no skin sensitization or cumulative skin

  10. Evaporation of methyl- and dimethyl-substituted malonic, succinic, glutaric and adipic acid particles at ambient temperatures

    DEFF Research Database (Denmark)

    Mønster, Jacob Garbrecht; Rosenørn, Thomas; Svenningsson, Birgitta

    2004-01-01

    Evaporation; organic aerosols; vapor pressure; dicarboxylic acid; maonic acid; succinic acid; glutaric acid; adipic acid......Evaporation; organic aerosols; vapor pressure; dicarboxylic acid; maonic acid; succinic acid; glutaric acid; adipic acid...

  11. Avocado and olive oil methyl esters

    International Nuclear Information System (INIS)

    Knothe, Gerhard

    2013-01-01

    Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, including commodity oils, however, the methyl esters of avocado and olive oil would likely be suitable as biodiesel fuel. In order to expand the database and comprehensive evaluation of the properties of vegetable oil esters, in this work the fuel-related properties of avocado and olive oil methyl esters, which exhibit similar fatty acid profiles including high oleic acid content, are determined. The cetane numbers of avocado oil methyl esters and olive oil methyl esters are relatively high, determined as 59.2 and 62.5, respectively, due to their elevated content of methyl oleate. Other properties are well within the ranges specified in biodiesel standards. The cloud points of both esters are slightly above 0 °C due to their content of saturated esters, especially methyl palmitate. Overall, avocado and olive oil yield methyl esters with fuel properties comparable to methyl esters from other commodity vegetable oils. The 1 H and 13 C NMR spectra of avocado and olive oil methyl esters are reported. -- Highlights: • Methyl esters of avocado and olive oil meet biodiesel fuel standards. • Provides comparison for methyl esters of other vegetable oils with high oleic content. • Discusses and compares present results with prior literature

  12. 40 CFR 721.8079 - Isophorone diisocyanate neopentyl glycol adipate polyurethane prepolymer.

    Science.gov (United States)

    2010-07-01

    ... glycol adipate polyurethane prepolymer. 721.8079 Section 721.8079 Protection of Environment ENVIRONMENTAL... adipate polyurethane prepolymer. (a) Chemical substance and significant new uses subject to reporting. (1... polyurethane prepolymer (PMN P-94-1743) is subject to reporting under this section for the significant new uses...

  13. High pressure direct synthesis of adipic acid from cyclohexene and hydrogen peroxide via capillary microreactors

    NARCIS (Netherlands)

    Shang, M.; Noël, T.; Su, Y.; Hessel, V.

    2016-01-01

    The direct synthesis of adipic acid from hydrogen peroxide and cyclohexene was investigated in capillary microreactors at high temperature (up to 115°C ) and pressure (up to 70 bar). High temperature was already applied in micro-flow packed-bed reactors for the direct adipic acid synthesis. In our

  14. Enzymatically and reductively degradable α-amino acid-based poly(ester amide)s: Synthesis, cell compatibility, and intracellular anticancer drug delivery

    NARCIS (Netherlands)

    Sun, H.; Cheng, Ru; Deng, Chao; Meng, Fenghua; Dias, Aylvin A.; Hendriks, Marc; Feijen, Jan; Zhong, Zhiyuan

    2015-01-01

    A novel and versatile family of enzymatically and reductively degradable α-amino acid-based poly(ester amide)s (SS-PEAs) were developed from solution polycondensation of disulfide-containing di-p-toluenesulfonic acid salts of bis-l-phenylalanine diesters (SS-Phe-2TsOH) with di-p-nitrophenyl adipate

  15. Aromatic and fatty acids of triterpene esters and rubber content of Hoya latices and their taxonomic significance

    NARCIS (Netherlands)

    Warnaar, F.

    1984-01-01

    The acid composition and the rubber content of the latices of 20 Hoya species were determined. All acids isolated from the latices were esterified with triterpenols and particle-bound. Cinnamic acid was the main acid in most latices. Acetic acid occurred in all latices, and predominated in three of

  16. Contents

    Directory of Open Access Journals (Sweden)

    Editor IJRED

    2012-11-01

    Full Text Available International Journal of Renewable Energy Development www.ijred.com Volume 1             Number 3            October 2012                ISSN 2252- 4940   CONTENTS OF ARTICLES page Design and Economic Analysis of a Photovoltaic System: A Case Study 65-73 C.O.C. Oko , E.O. Diemuodeke, N.F. Omunakwe, and E. Nnamdi     Development of Formaldehyde Adsorption using Modified Activated Carbon – A Review 75-80 W.D.P Rengga , M. Sudibandriyo and M. Nasikin     Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC 81-86 A. Buasri , B. Ksapabutr, M. Panapoy and N. Chaiyut     Wind Resource Assessment in Abadan Airport in Iran 87-97 Mojtaba Nedaei       The Energy Processing by Power Electronics and its Impact on Power Quality 99-105 J. E. Rocha and B. W. D. C. Sanchez       First Aspect of Conventional Power System Assessment for High Wind Power Plants Penetration 107-113 A. Merzic , M. Music, and M. Rascic   Experimental Study on the Production of Karanja Oil Methyl Ester and Its Effect on Diesel Engine 115-122 N. Shrivastava,  , S.N. Varma and M. Pandey  

  17. Multifunctional nanobiocomposite of Poly[(butylene succinate)-co-adipate] and clay

    CSIR Research Space (South Africa)

    Al-Thabaiti, SA

    2015-03-01

    Full Text Available The processing and characterization of multifunctional nanobiocomposite of biodegradable poly[(butylene succinate)-co-adipate] (PBSA) and organically modified synthetic fluorine mica (OSFM) are reported. The nanobiocomposite of PBSA with OSFM...

  18. Biodegradação de alcoóis, ftalatos e adipatos em um solo tropical contaminado Biodegradation of alcohol, phthalates and adipates in a tropical soil

    Directory of Open Access Journals (Sweden)

    Ieda Domingues Ferreira

    2010-01-01

    Full Text Available The adipic and phthalic acid esters are plasticizers, have low water solubility, high partition octanol/water coefficients (Kow and accumulate in soil and sediments. These compounds are considered teratogenic, carcinogenic and endocrine disruptors chemicals. This study evaluated the bioremediation of tropical soil contaminated with plasticizers process wastes, in aerobic conditions, with and without introduction of acclimated bacteria. It was selected 200 kg of contaminated tropical soil for the biodegradation study. The plasticizers concentrations in soil ranged between 153 mgDOA/kg up to 15552 mgDIDP/kg and after 90 days of biodegradation, the lower removal efficiencies were 72% with a 1-2 log simultaneous bacterial growth.

  19. Processing and rheological characterization of poly(butylene adipate co-terephalate)/montmorillonite nanocomposites

    International Nuclear Information System (INIS)

    Beatrice, Cesar A.G.; Marini, Juliano; Bretas, Rosario E.S.; Branciforti, Marcia C.; Favaro, Marcia M.

    2009-01-01

    The rheological steady state and the linear viscoelastic properties of poly(butylene adipate co-terephthalate) (PBAT) / nanoclay nanocomposites were investigated. For this study, nanocomposites of PBAT and a chemically modified montmorillonite (MMT) were prepared by melt blending in a Haake Rheomix 600p rheometer at 140 and 160 deg C. The concentration of nanoclay was 5wt%. The samples obtained were characterized by x-ray diffraction (WAXS) and rheological measurements in an ARES (Rheometric Scientific) and AR-G2 (TA) rheometers, both with parallel plates geometry. It was confirmed by WAXS that the platelets of the nanoclay were intercalated in all samples, as the discernible sharp reflection of the (001) clay's diffraction was found in the x-ray diffractions patterns. The storage moduli (G') and the loss moduli (G ) of the nanocomposites increased with nanoclay content, at low frequencies. The presence of nanoclay caused these nanocomposites melts to have solid-like behaviors, which can be explained in terms of the development of a percolated network structure. (author)

  20. A limited LCA of bio-adipic acid: Manufacturing the nylon-6,6 precursor adipic acid using the benzoic acid degradation pathway from different feedstocks

    NARCIS (Netherlands)

    Duuren, van J.B.J.H.; Brehmer, B.; Mars, A.E.; Eggink, G.; Martins Dos Santos, V.A.P.; Sanders, J.P.M.

    2011-01-01

    A limited life cycle assessment (LCA) was performed on a combined biological and chemical process for the production of adipic acid, which was compared to the traditional petrochemical process. The LCA comprises the biological conversion of the aromatic feedstocks benzoic acid, impure aromatics,

  1. Preparation of deuteriated adipic [2H2]-, [2H4]-, [2H6]-, and [2H8]-acids by use of Kolbe electrolysis as a key reaction

    International Nuclear Information System (INIS)

    Tashiro, Masahi; Tsuzuki, Hirohisa; Mataka, Shuntaro; Goto, Hideyuki; Ogasahara, Shoji

    1990-01-01

    Using Kolbe electrolysis of methyl hydrogen [ 2 H 0 ]-, [ 2 H 2 ]-, and [ 2 H 4 ]-succinates as a key reaction, adipic [2,2- 2 H 2 ]-, [2,3- 2 H 2 ]-, [2,2,3,3- 2 H 4 ]-, [2,3,4,5- 2 H 4 ]-, [2,3,5,5- 2 H 4 ]-, [2,2,3,3,5,5- 2 H 6 ]-, and [2,2,3,3,4,4,5,5- 2 H 8 ]-acids were prepared in high deuterium contents. (author)

  2. 78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

    Science.gov (United States)

    2013-04-03

    ..., Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance Exemption AGENCY... from the requirement of a tolerance for residues of castor oil, polymer with adipic acid, linoleic acid... pesticide formulation. Advance Polymer Technology submitted a petition to EPA under the Federal Food, Drug...

  3. Development of silver/titanium dioxide/chitosan adipate nanocomposite as an antibacterial coating for fruit storage

    Science.gov (United States)

    A novel nanocomposite of silver/titanium dioxide/chitosan adipate (Ag/TiO2/CS) was developed through photochemical reduction using a chitosan adipate template. Chitosan served as a reducing agent for the metal ions, and anchored metal ions by forming Ag–N coordination bonds and electrostatic attract...

  4. Effect of addition of lignin in physical-chemical properties of a polyesters based on glycerol, phthalic and adipic acids; Efeito da adicao de lignina nas propriedades fisico-quimicas de poliesteres a base de glicerol e acidos ftalico e adipico

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, D.H.; Viana, A.P.M.; Lima, A.S.C.; Goncalves, A.P.B.; Miranda, C.S.; Jose, N.M., E-mail: dhanseng@yahoo.com.br [Universidade Federal da Bahia (UFBA), alvador, BA (Brazil)

    2014-07-01

    In this paper the study of different addition amounts of lignin in the physicochemical properties of polyesters made from glycerol and different amounts of phthalic and adipic acids have been proposed. The following characterizations were made: XRD, FTIR, TGA, DSC and SEM. The variation in the percentage of adipic and phthalic acids had a direct effect on thermal and morphological properties. The thermal analysis showed that there was miscibility between the polyester and lignin, by means of displacement related to the temperature of thermal degradation events. In FTIR analysis was noted displacements of characteristic bands of hydrogen bonds and specific carbonyl ester groups. These shifts were more pronounced as it has larger amounts of phthalic acid as monomer and larger amounts of lignin in the compositions. (author)

  5. Application conditions for ester cured alkaline phenolic resin sand

    Directory of Open Access Journals (Sweden)

    Ren-he Huang

    2016-07-01

    Full Text Available Five organic esters with different curing speeds: propylene carbonate (i.e. high-speed ester A; 1, 4-butyrolactone; glycerol triacetate (i.e. medium-speed ester B; glycerol diacetate; dibasic ester (DBE (i.e. low-speed ester C, were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin. The relationships between the curing performances of the resin (including pH value, gel pH value, gel time of resin solution, heat release rate of the curing reaction and tensile strength of the resin sand and the amount of added organic ester and curing temperature were investigated. The results indicated the following: (1 The optimal added amount of organic ester should be 25wt.%-30wt.% of alkaline phenolic resin and it must be above 20wt.%-50 wt.% of the organic ester hydrolysis amount. (2 High-speed ester A (propylene carbonate has a higher curing speed than 1, 4-butyrolactone, and they were both used as high-speed esters. Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand; glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin. (3 High-speed ester A, medium-speed ester B (glycerol triacetate and low-speed ester C (dibasic ester, i.e., DBE should be used below 15 ìC, 35 ìC and 50 ìC, respectively. High-speed ester A or low-speed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand. (4 There should be a suitable solid content (generally 45wt.%-65wt.% of resin, alkali content (generally 10wt.%-15wt.% of resin and viscosity of alkaline phenolic resin (generally 50-300 mPa≤s in the preparation of alkaline phenolic resin. Finally, the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

  6. A limited LCA of bio-adipic acid: manufacturing the nylon-6,6 precursor adipic acid using the benzoic acid degradation pathway from different feedstocks.

    Science.gov (United States)

    van Duuren, J B J H; Brehmer, B; Mars, A E; Eggink, G; Dos Santos, V A P Martins; Sanders, J P M

    2011-06-01

    A limited life cycle assessment (LCA) was performed on a combined biological and chemical process for the production of adipic acid, which was compared to the traditional petrochemical process. The LCA comprises the biological conversion of the aromatic feedstocks benzoic acid, impure aromatics, toluene, or phenol from lignin to cis, cis-muconic acid, which is subsequently converted to adipic acid through hydrogenation. Apart from the impact of usage of petrochemical and biomass-based feedstocks, the environmental impact of the final concentration of cis, cis-muconic acid in the fermentation broth was studied using 1.85% and 4.26% cis, cis-muconic acid. The LCA focused on the cumulative energy demand (CED), cumulative exergy demand (CExD), and the CO(2) equivalent (CO(2) eq) emission, with CO(2) and N(2) O measured separately. The highest calculated reduction potential of CED and CExD were achieved using phenol, which reduced the CED by 29% and 57% with 1.85% and 4.26% cis, cis-muconic acid, respectively. A decrease in the CO(2) eq emission was especially achieved when the N(2) O emission in the combined biological and chemical process was restricted. At 4.26% cis, cis-muconic acid, the different carbon backbone feedstocks contributed to an optimized reduction of CO(2) eq emissions ranging from 14.0 to 17.4 ton CO(2) eq/ton adipic acid. The bulk of the bioprocessing energy intensity is attributed to the hydrogenation reactor, which has a high environmental impact and a direct relationship with the product concentration in the broth. Copyright © 2011 Wiley Periodicals, Inc.

  7. Preparation of Nanocellulose Reinforced Chitosan Films, Cross-Linked by Adipic Acid

    Directory of Open Access Journals (Sweden)

    Pouria Falamarzpour

    2017-02-01

    Full Text Available Adipic acid, an abundant and nontoxic compound, was used to dissolve and cross-link chitosan. After the preparation of chitosan films through casting technique, the in situ amidation reaction was performed at 80–100 °C as verified by Fourier transform infrared (FT-IR. The reaction was accompanied by the release of water which was employed to investigate the reaction kinetics. Accordingly, the reaction rate followed the first-order model and Arrhenius equation, and the activation energy was calculated to be 18 kJ/mol. Furthermore, the mechanical properties of the chitosan films were comprehensively studied. First, optimal curing conditions (84 °C, 93 min were introduced through a central composite design. In order to evaluate the effects of adipic acid, the mechanical properties of physically cross-linked (uncured, chemically cross-linked (cured, and uncross-linked (prepared by acetic acid films were compared. The use of adipic acid improved the tensile strength of uncured and chemically cross-linked films more than 60% and 113%, respectively. Finally, the effect of cellulose nanofibrils (CNFs on the mechanical performance of cured films, in the presence of glycerol as a plasticizer, was investigated. The plasticized chitosan films reinforced by 5 wt % CNFs showed superior properties as a promising material for the development of chitosan-based biomaterials.

  8. Preparation of Nanocellulose Reinforced Chitosan Films, Cross-Linked by Adipic Acid.

    Science.gov (United States)

    Falamarzpour, Pouria; Behzad, Tayebeh; Zamani, Akram

    2017-02-13

    Adipic acid, an abundant and nontoxic compound, was used to dissolve and cross-link chitosan. After the preparation of chitosan films through casting technique, the in situ amidation reaction was performed at 80-100 °C as verified by Fourier transform infrared (FT-IR). The reaction was accompanied by the release of water which was employed to investigate the reaction kinetics. Accordingly, the reaction rate followed the first-order model and Arrhenius equation, and the activation energy was calculated to be 18 kJ/mol. Furthermore, the mechanical properties of the chitosan films were comprehensively studied. First, optimal curing conditions (84 °C, 93 min) were introduced through a central composite design. In order to evaluate the effects of adipic acid, the mechanical properties of physically cross-linked (uncured), chemically cross-linked (cured), and uncross-linked (prepared by acetic acid) films were compared. The use of adipic acid improved the tensile strength of uncured and chemically cross-linked films more than 60% and 113%, respectively. Finally, the effect of cellulose nanofibrils (CNFs) on the mechanical performance of cured films, in the presence of glycerol as a plasticizer, was investigated. The plasticized chitosan films reinforced by 5 wt % CNFs showed superior properties as a promising material for the development of chitosan-based biomaterials.

  9. 76 FR 7703 - 1,4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4-Butanediol, Adipic Acid, and...

    Science.gov (United States)

    2011-02-11

    ...., textiles (clothing and diapers), carpets, swimming pools, and hard surface disinfection on walls, floors... Regulations That Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001) or...

  10. Preliminary study of the influence of CO2 extraction conditions on the ester, aldehyde, ketone and hydrocarbon content of grape bagasses from jam production

    Directory of Open Access Journals (Sweden)

    J. Santos

    2007-12-01

    Full Text Available The main objective of this work was to assess the influence of temperature and pressure on the chemical characteristics of the essential oil obtained from CO2 extraction of grape bagasses in the production of jam. The experiments were performed in a laboratory-scale unit, where the effect of temperature (290 and 303 K and pressure (15 and 25 Mpa was investigated in terms of liquid yield and chemical composition of the extracts. The CO2 mass flow rate was kept within a range of 2.5 to 3.0 g/min. The instrumental analysis was performed by gas chromatography with a mass spectrometer detector (GC-MS. The extraction conditions investigated in this work had no significant influence on the mass of essencial oil extracted. The main compounds identified in the extracts by the GC-MS spectra library (match quality higher tan 90% were octadecane, dihydroxy ergostene-dione and phenylethyl n-decanoate when the temperature was increased from 290 to 303 K. Heptanal, ethyl ester of decosonoic acid and hexatriacontane were the individual compounds with the greatest increase in the chromatographic peak area when the pressure was increased from 15 to 25 Mpa. The most important class of compounds were hydrocarbons at 303 K and 15 MPa and were ketones and aldehydes at 25 Mpa and 290 K.

  11. Determination of the content of fatty acid methyl esters (FAME) in biodiesel samples obtained by esterification using 1H-NMR spectroscopy.

    Science.gov (United States)

    Mello, Vinicius M; Oliveira, Flavia C C; Fraga, William G; do Nascimento, Claudia J; Suarez, Paulo A Z

    2008-11-01

    Three different calibration curves based on (1)H-NMR spectroscopy (300 MHz) were used for quantifying the reaction yield during biodiesel synthesis by esterification of fatty acids mixtures and methanol. For this purpose, the integrated intensities of the hydrogens of the ester methoxy group (3.67 ppm) were correlated with the areas related to the various protons of the alkyl chain (olefinic hydrogens: 5.30-5.46 ppm; aliphatic: 2.67-2.78 ppm, 2.30 ppm, 1.96-2.12 ppm, 1.56-1.68 ppm, 1.22-1.42 ppm, 0.98 ppm, and 0.84-0.92 ppm). The first curve was obtained using the peaks relating the olefinic hydrogens, a second with the parafinic protons and the third curve using the integrated intensities of all the hydrogens. A total of 35 samples were examined: 25 samples to build the three different calibration curves and ten samples to serve as external validation samples. The results showed no statistical differences among the three methods, and all presented prediction errors less than 2.45% with a co-efficient of variation (CV) of 4.66%. 2008 John Wiley & Sons, Ltd.

  12. Content

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    secondary levels. In subject matter didactics, the question of content is more developed, but it is still mostly confined to teaching on lower levels. As for higher education didactics, discussions on selection of content are almost non-existent on the programmatic level. Nevertheless, teachers are forced...... curriculum, in higher education, and to generate analytical categories and criteria for selection of content, which can be used for systematic didactical reflection. The larger project also concerns reflection on and clarification of the concept of content, including the relation between content at the level......Aim, content and methods are fundamental categories of both theoretical and practical general didactics. A quick glance in recent pedagogical literature on higher education, however, reveals a strong preoccupation with methods, i.e. how teaching should be organized socially (Biggs & Tang, 2007...

  13. The liquid–liquid coexistence curves of {x dimethyl adipate + (1 − x) n-hexane} and {x dimethyl adipate + (1 − x) n-heptane} in the critical region

    International Nuclear Information System (INIS)

    Chen Zhiyun; Cai Li; Huang Meijun; Yin Tianxiang; An Xueqin; Shen Weiguo

    2012-01-01

    Highlights: ► Coexistence curves of (dimethyl adipate + n-hexane) (+n-heptane) were measured. ► The critical exponent β are consistent with the 3D-Ising value. ► The asymmetry of the coexistence curves were discussed by complete scaling theory. - Abstract: The liquid–liquid coexistence curves for (dimethyl adipate + n-hexane), (dimethyl adipate + n-heptane) have been measured, from which the critical amplitudes and the critical exponents are deduced. The critical exponent β corresponding to the coexistence curves are consistent with the 3D-Ising value. The experimental results have also been analyzed to determine the critical amplitudes of Wegner-correction terms when β and Δ are fixed at their theoretical values, and to examine the asymmetry of the diameters for the coexistence curves.

  14. Synthesis of fatty acid methyl ester from the transesterification of high- and low-acid-content crude palm oil (Elaeis guineensis) and karanj oil (Pongamia pinnata) over a calcium-lanthanum-aluminum mixed-oxides catalyst.

    Science.gov (United States)

    Syamsuddin, Y; Murat, M N; Hameed, B H

    2016-08-01

    The synthesis of fatty acid methyl ester (FAME) from the high- and low-acid-content feedstock of crude palm oil (CPO) and karanj oil (KO) was conducted over CaO-La2O3-Al2O3 mixed-oxide catalyst. Various reaction parameters were investigated using a batch reactor to identify the best reaction condition that results in the highest FAME yield for each type of oil. The transesterification of CPO resulted in a 97.81% FAME yield with the process conditions of 170°C reaction temperature, 15:1 DMC-to-CPO molar ratio, 180min reaction time, and 10wt.% catalyst loading. The transesterification of KO resulted in a 96.77% FAME yield with the conditions of 150°C reaction temperature, 9:1 DMC-to-KO molar ratio, 180min reaction time, and 5wt.% catalyst loading. The properties of both products met the ASTM D6751 and EN 14214 standard requirements. The above results showed that the CaO-La2O3-Al2O3 mixed-oxide catalyst was suitable for high- and low-acid-content vegetable oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Toward Synthetic Biology Strategies for Adipic Acid Production: An in Silico Tool for Combined Thermodynamics and Stoichiometric Analysis of Metabolic Networks

    DEFF Research Database (Denmark)

    Averesch, Nils J. H.; Martínez, Verónica S.; Nielsen, Lars K.

    2018-01-01

    Adipic acid, a nylon-6,6 precursor, has recently gained popularity in synthetic biology. Here, 16 different production routes to adipic acid were evaluated using a novel tool for network-embedded thermodynamic analysis of elementary flux modes. The tool distinguishes between thermodynamically...

  16. Synthesis, characterization and thermal degradation of cross-linked polystyrene using the alkyne-functionalized esters as a cross-linker agent by click chemistry method

    Directory of Open Access Journals (Sweden)

    Hakan Akat

    2015-08-01

    Full Text Available AbstractIn this study, it has been demonstrated that cross-linked polystyrene (CPS was successfully prepared by using click chemistry. For this purpose, firstly, poly (styrene-co-4 chloromethylstyrene with 4-chloromethylstyrene was synthesized. Secondly, alkyne-functionalized esters (dipropargyl adipate, dipropargyl succinate were obtained using propargyl alcohol, adipoyl chloride and succinyl chloride. Azide-functionalized polystrene (PS-N3 and dipropargyl adipate (or dipropargyl succinate were reacted in N,N-dimethylformamide for 24 h at room temperature to give CPS. The synthesized polymer and compounds were characterized by nuclear magnetic resonance (1H-NMR, gel permeation chromatography (GPC, fourier transform infrared spectroscopy (FT-IR and thermogravimetric (TG/DTG analysis.. The surface properties were investigated by Scanning Electron Micrography (SEM.

  17. Ester Tuiksoo / Ester Tuiksoo ; interv. Piret Tali

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Juhan Partsi valitsuse (05.04.2004-13.04.2005) ja Andrus Ansipi valitsuse (13.04.2005-) põllumajandusminister Ester Tuiksoo oma lapsepõlvest ja elukutsevalikust, poliitilise karjääri algusest ja erakonna valikust, ministritöö kogemustest, naistest poliitikas

  18. Variability of some diterpene esters in coffee beverages as influenced by brewing procedures.

    Science.gov (United States)

    Moeenfard, Marzieh; Erny, Guillaume L; Alves, Arminda

    2016-11-01

    Several coffee brews, including classical and commercial beverages, were analyzed for their diterpene esters content (cafestol and kahweol linoleate, oleate, palmitate and stearate) by high performance liquid chromatography with diode array detector (HPLC-DAD) combined with spectral deconvolution. Due to the coelution of cafestol and kahweol esters at 225 nm, HPLC-DAD did not give accurate quantification of cafestol esters. Accordingly, spectral deconvolution was used to deconvolve the co-migrating profiles. Total cafestol and kahweol esters content of classical coffee brews ranged from 5-232 to 2-1016 mg/L, respectively. Commercial blends contained 1-54 mg/L of total cafestol esters and 2-403 mg/L of total kahweol esters. Boiled coffee had the highest diterpene esters content, while filtered and instant brews showed the lowest concentrations. However, individual diterpene esters content was not affected by brewing procedure as in terms of kahweol esters, kahweol palmitate was the main compound in all samples, followed by kahweol linoleate, oleate and stearate. Higher amounts of cafestol palmitate and stearate were also observed compared to cafestol linoleate and cafestol oleate. The ratio of diterpene esters esterified with unsaturated fatty acids to total diterpene esters was considered as measure of their unsaturation in analyzed samples which varied from 47 to 52%. Providing new information regarding the diterpene esters content and their distribution in coffee brews will allow a better use of coffee as a functional beverage.

  19. Poly(glycerol adipate) - indomethacin drug conjugates - synthesis and in vitro characterization.

    Science.gov (United States)

    Wersig, T; Hacker, M C; Kressler, J; Mäder, K

    2017-10-05

    The linear biodegradable polyester poly(glycerol adipate) (PGA) was synthesized via enzymatic polycondensation using lipase B from Candida antarctica (CAL-B). Every monomer unit of PGA possesses a pendant hydroxyl group which is responsible for the hydrophilic character and moisture swelling. These OH groups were esterified to different degrees with the anti-inflammatory drug indomethacin in order to create a prodrug with a pH-sensitive linker for modified drug release. The structure of the conjugates was determined via ATR FT-IR spectroscopy, NMR spectroscopy, GPC and UV/VIS spectroscopy. The physical properties of polymers with different drug load were investigated using DSC, contact angle measurements and oscillatory rheology. Drug release was monitored over one month in vitro. A very slow, but continuous release was observed in PBS. Slightly acidic conditions and lipase activity are accelerating the indomethacin release. Therefore, poly(glycerol adipate) - indomethacin conjugates are promising prodrugs for the local sustained release of indomethacin. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Engineering a Polyketide Synthase for In Vitro Production of Adipic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, A; Poust, S; De Rond, T; Fortman, JL; Katz, L; Petzold, CJ; Keasling, JD

    2015-10-26

    Polyketides have enormous structural diversity, yet polyketide synthases (PKSs) have thus far been engineered to produce only drug candidates or derivatives thereof. Thousands of other molecules, including commodity and specialty chemicals, could be synthesized using PKSs if composing hybrid PKSs from well-characterized parts derived from natural PKSs was more efficient. Here, using modern mass spectrometry techniques as an essential part of the design–build–test cycle, we engineered a chimeric PKS to enable production one of the most widely used commodity chemicals, adipic acid. To accomplish this, we introduced heterologous reductive domains from various PKS clusters into the borrelidin PKS’ first extension module, which we previously showed produces a 3-hydroxy-adipoyl intermediate when coincubated with the loading module and a succinyl-CoA starter unit. Acyl-ACP intermediate analysis revealed an unexpected bottleneck at the dehydration step, which was overcome by introduction of a carboxyacyl-processing dehydratase domain. Appending a thioesterase to the hybrid PKS enabled the production of free adipic acid. Using acyl-intermediate based techniques to “debug” PKSs as described here, it should one day be possible to engineer chimeric PKSs to produce a variety of existing commodity and specialty chemicals, as well as thousands of chemicals that are difficult to produce from petroleum feedstocks using traditional synthetic chemistry.

  1. Poly(butylene adipate-co-terephthalate) and sunflower head residue composites: Effects of composition and compatibilization on properties

    Science.gov (United States)

    Utilizing the abundant byproducts generated from processing of agricultural materials has sustainable and cost–saving potential benefits. In this work, Sunflower Head Residues (SHR) in 3 different compositions were introduced into biodegradable Poly(butylene adipate-co-terephthalate) (PBAT) matrices...

  2. cis,cis-Muconic acid: separation and catalysis to bio-adipic acid for nylon-6,6 polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Vardon, Derek R.; Rorrer, Nicholas A.; Salvachúa, Davinia; Settle, Amy E.; Johnson, Christopher W.; Menart, Martin J.; Cleveland, Nicholas S.; Ciesielski, Peter N.; Steirer, K. Xerxes; Dorgan, John R.; Beckham, Gregg T.

    2016-01-01

    cis,cis-Muconic acid is a polyunsaturated dicarboxylic acid that can be produced renewably via the biological conversion of sugars and lignin-derived aromatic compounds. Subsequently, muconic acid can be catalytically converted to adipic acid -- the most commercially significant dicarboxylic acid manufactured from petroleum. Nylon-6,6 is the major industrial application for adipic acid, consuming 85% of market demand; however, high purity adipic acid (99.8%) is required for polymer synthesis. As such, process technologies are needed to effectively separate and catalytically transform biologically derived muconic acid to adipic acid in high purity over stable catalytic materials. To that end, this study: (1) demonstrates bioreactor production of muconate at 34.5 g L-1 in an engineered strain of Pseudomonas putida KT2440, (2) examines the staged recovery of muconic acid from culture media, (3) screens platinum group metals (e.g., Pd, Pt, Rh, Ru) for activity and leaching stability on activated carbon (AC) and silica supports, (4) evaluates the time-on-stream performance of Rh/AC in a trickle bed reactor, and (5) demonstrates the polymerization of bio-adipic acid to nylon-6,6. Separation experiments confirmed AC effectively removed broth color compounds, but subsequent pH/temperature shift crystallization resulted in significant levels of Na, P, K, S and N in the crystallized product. Ethanol dissolution of muconic acid precipitated bulk salts, achieving a purity of 99.8%. Batch catalysis screening reactions determined that Rh and Pd were both highly active compared to Pt and Ru, but Pd leached significantly (1-9%) from both AC and silica supports. Testing of Rh/AC in a continuous trickle bed reactor for 100 h confirmed stable performance after 24 h, although organic adsorption resulted in reduced steady-state activity. Lastly, polymerization of bio-adipic acid with hexamethyldiamine produced nylon-6,6 with comparable properties to its petrochemical counterpart

  3. Rapid NIR determination of alkyl esters in virgin olive oil

    International Nuclear Information System (INIS)

    Cayuela, J.A.

    2017-01-01

    The regulation of The European Union for olive oil and olive pomace established the limit of 35 mg·kg-1 for fatty acids ethyl ester contents in extra virgin olive oils, from grinding seasons after 2016. In this work, predictive models have been established for measuring fatty acid ethyl and methyl esters and to measure the total fatty acid alkyl esters based on near infrared spectroscopy (NIRS), and used successfully for this purpose. The correlation coefficients from the external validation exercises carried out with these predictive models ranged from 0.84 to 0.91. Different classification tests using the same models for the thresholds 35 mg·kg-1 for fatty acid ethyl esters and 75 mg·kg-1 for fatty acid alkyl esters provided success percentages from 75.0% to 95.2%. [es

  4. Langzeitevaluation eines psychologischen Trainings für adipöse Kinder und ihre Eltern (TAKE)

    OpenAIRE

    Roth, Binia; Munsch, Simone; Meyer, Andrea H.

    2011-01-01

    Verhaltenstherapeutische Eltern-Kind-Programme haben bisher die besten Effekte bei der Behandlung kindlicher Adipositas gezeigt. Mit TAKE (Training adipöser Kinder und ihrer Eltern) stellen wir eine psychologiebasierte Behandlung vor, die nicht nur Bewegung, Ernährung und Essverhalten als Elemente einschließt, sondern auch psychische Faktoren wie Selbstwertgefühl, Körperbild, soziale Kompetenzen und Hänseleien sowohl mit den Eltern als auch mit den Kindern behandelt. Aktuell liegen die Langze...

  5. Flexible and strong ternary blends of poly(vinyl chloride), poly(butylene adipate)and nanoparticle-plasticizers

    OpenAIRE

    Yin, Bo; Hakkarainen, Minna

    2013-01-01

    Multiple property enhancement was achieved for ternary blends of PVC, poly(butylene adipate) (PBA) plasticizer and PBA-grafted nanofillers as compared to ternary blends with untreated nanofillers. The blends with surface modified halloysite, kaolin or silicon dioxide nanofillers all exhibited higher stress at break and higher strain at break as compared to the corresponding composites with untreated nanoparticles. The strain at break was similar or improved compared to binary PVC/PBA blends. ...

  6. Preparation of polyol esters based on vegetable and animal fats.

    Science.gov (United States)

    Gryglewicz, S; Piechocki, W; Gryglewicz, G

    2003-03-01

    The possibility of using some natural fats: rapeseed oil, olive oil and lard, as starting material for the preparation of neopentyl glycol (NPG) and trimethylol propane (TMP) esters is reported. The syntheses of final products were performed by alcoholysis of fatty acid methyl esters, obtained from natural fats studied, with the appropriate polyhydric alcohol using calcium methoxide as a catalyst. The basic physicochemical properties of the NPG and TMP esters synthesized were the following: viscosity at 40 degrees C in the range of 13.5-37.6 cSt, pour point between -10.5 and -17.5 degrees C and very high viscosity indices, higher than 200. Generally, the esters of neopentyl alcohols were characterized by higher stability in thermo-oxidative conditions in comparison to native triglycerides. Due to the low content of polyunsaturated acids, the olive oil based esters showed the highest thermo-oxidative resistance. Also, methyl esters of fatty acids of lard would constitute a good raw material for the synthesis of lubricating oils, provided that their saturated acids content was lowered. This permits synthesis of NPG and TMP esters with a lower pour point (below -10 degrees C) than natural lard (+33 degrees C).

  7. Carboxylesterase-dependent cytotoxicity of dibasic esters (DBE) in rat nasal explants.

    Science.gov (United States)

    Trela, B A; Bogdanffy, M S

    1991-02-01

    Dibasic esters (DBE) are a solvent mixture of dimethyl adipate (DMA), dimethyl glutarate (DMG), and dimethyl succinate (DMS) used in the paint and coating industry. Subchronic inhalation toxicity studies have demonstrated that DBE induce a mild degeneration of the olfactory, but not the respiratory, epithelium of the rat nasal cavity. Carboxylesterase-mediated hydrolysis of the individual dibasic esters is more efficient in olfactory than in respiratory mucosal homogenates. In the present study, an in vitro system of cultured rat nasal explants was utilized to determine if DBE toxicity is dependent on a metabolic activation by nonspecific carboxylesterase. Explants from both the olfactory and the respiratory regions of the female rat nasal cavity were incubated for 2 hr in Williams' medium E containing 10-100 mM DMA, DMG, or DMS. DBE caused a dose-related increase in nasal explant acid phosphatase release, a biochemical index of cytotoxicity. HPLC analysis demonstrated parallel increases in the carboxylesterase-mediated formation of monomethyl ester metabolites. Diacid metabolite production in the nasal explant system was not entirely concentration-dependent. Metabolite concentrations and acid phosphatase release were generally greater in olfactory than respiratory tissues. DBE-induced cytotoxicity and acid metabolite production were markedly attenuated in nasal tissue excised from rats which were pretreated with bis(p-nitrophenyl)phosphate, a carboxylesterase inhibitor. This study presents a viable in vitro method for assessing organic ester cytotoxicity in the rat nasal cavity. It was shown that DBE are weak nasal toxicants under the conditions of this system. It was further demonstrated that DBE toxicity is dependent on a carboxylesterase-mediated activation. A similar mechanism was proposed for the nasal toxicity induced by other organic esters following inhalation exposure.

  8. Valyl benzyl ester chloride

    Directory of Open Access Journals (Sweden)

    Grzegorz Dutkiewicz

    2010-02-01

    Full Text Available In the title compound (systematic name: 1-benzyloxy-3-methyl-1-oxobutan-2-aminium chloride, C12H18NO2+·Cl−, the ester group is approximately planar, with a maximum deviation of 0.040 (2 Å from the least-squares plane, and makes a dihedral angle of 28.92 (16° with the phenyl ring. The crystal structure is organized by N—H...Cl hydrogen bonds which join the two components into a chain along the b axis. Pairs of chains arranged antiparallel are interconnected by further N—H...Cl hydrogen bonds, forming eight-membered rings. Similar packing modes have been observed in a number of amino acid ester halides with a short unit-cell parameter of ca 5.5 Å along the direction in which the chains run.

  9. Starch/poly (butylene adipate-co-terephthalate/montmorillonite films produced by blow extrusion

    Directory of Open Access Journals (Sweden)

    Rodrigo A. L. Santos

    2014-07-01

    Full Text Available This study aims to prepare biodegradable films from cassava starch, poly (butylene adipate-co-terephthalate (PBAT, and montmorillonite (MMT using blow-extrusion process and analyze the effects of different types and concentrations of MMT on the microstructure, physicochemical, and mechanical properties of the resulting films. The films were produced by blending 30% of PBAT with glycerol (17.5%, starch (49.0-52.5%, and four different types of montmorillonite (Cloisite® Na+, 10A, 15A, and 30B at two different concentrations (1.75% and 3.5%. All the films prepared in this study showed an increase in the basal spacing of MMT layers. In particular, the films with 10A and 30B showed the highest increase in intercalation basal spacing, suggesting the formation of intercalated composites. The addition of nanoclays decreased the elongation of films. The addition of Cloisite® 10A resulted in films with the lowest WVP values and the highest stability to water adsorption under different RH conditions.

  10. Regulated and unregulated emissions from a diesel engine fueled with diesel fuel blended with diethyl adipate

    Science.gov (United States)

    Zhu, Ruijun; Cheung, C. S.; Huang, Zuohua; Wang, Xibin

    2011-04-01

    Experiments were carried out on a four-cylinder direct-injection diesel engine operating on Euro V diesel fuel blended with diethyl adipate (DEA). The blended fuels contain 8.1%, 16.4%, 25% and 33.8% by volume fraction of DEA, corresponding to 3%, 6%, 9% and 12% by mass of oxygen in the blends. The engine performance and exhaust gas emissions of the different fuels were investigated at five engine loads at a steady speed of 1800 rev/min. The results indicated an increase of brake specific fuel consumption and brake thermal efficiency when the engine was fueled with the blended fuels. In comparison with diesel fuel, the blended fuels resulted in an increase in hydrocarbon (HC) and carbon monoxide (CO), but a decrease in particulate mass concentrations. The nitrogen oxides (NO x) emission experienced a slight variation among the test fuels. In regard to the unregulated gaseous emissions, formaldehyde and acetaldehyde increased, while 1,3-butadiene, ethene, ethyne, propylene and BTX (benzene, toluene and xylene) in general decreased. A diesel oxidation catalyst (DOC) was found to reduce significantly most of the investigated unregulated pollutants when the exhaust gas temperature was sufficiently high.

  11. Apomorphine and its esters

    DEFF Research Database (Denmark)

    Borkar, Nrupa; Chen, Zhizhong; Saaby, Lasse

    2016-01-01

    Oral delivery of apomorphine via prodrug principle may be a potential treatment for Parkinson's disease. The purpose of this study was to investigate the transport and stability of apomorphine and its esters across Caco-2 cell monolayer and their affinity towards chylomicrons. Apomorphine......, monolauroyl apomorphine (MLA) and dilauroyl apomorphine (DLA) were subjected to apical to basolateral (A-B) and basolateral to apical (B-A) transport across Caco-2 cell monolayer. The stability of these compounds was also assessed by incubation at intestinal pH and physiological pH with and without Caco-2...

  12. Esters with water esters 2-c to 6-c

    CERN Document Server

    Getzen, F W; Hefter, G T; Maczynski, Andrzej

    1992-01-01

    This volume is the first of two devoted to esters and water. It includes solubility data for binary systems containing an ester and water up to the end of 1988. The critical evaluations were all prepared by one author and an introductory section has been included to elaborate the philosophy and methodology followed in the evaluations.

  13. Langzeitevaluation des psychologischen Trainings für adipöse Kinder und deren Eltern : TAKE

    OpenAIRE

    Roth, B.; Munsch, S.; Meyer, A. H.

    2011-01-01

    Cognitive-behavioral parent-child-programmes have shown the best effects in treating childhood obesity so far. With TAKE (Training adipöser Kinder und ihrer Eltern) we introduce a psychologically-informed training, that includes physical activity, nutrition and eating behavior but also addresses psychological issues like self-confidence, body image, social and anti-bullying skills. Long-term data from up to 64 month-follow-up showed moderate effects on body-mass index standard deviation score...

  14. Myo-inositol esters of indole-3-acetic acid are endogenous components of Zea mays L. shoot tissue

    Science.gov (United States)

    Chisnell, J. R.

    1984-01-01

    Indole-3-acetyl-myo-inositol esters have been demonstrated to be endogenous components of etiolated Zea mays shoots tissue. This was accomplished by comparison of the putative compounds with authentic, synthetic esters. The properties compared were liquid and gas-liquid chromatographic retention times and the 70-ev mass spectral fragmentation pattern of the pentaacetyl derivative. The amount of indole-3-acetyl-myo-inositol esters in the shoots was determined to be 74 nanomoles per kilogram fresh weight as measured by isotope dilution, accounting for 19% of the ester indole-3-acetic acid of the shoot. This work is the first characterization of an ester conjugate of indole-3-acetate acid from vegetative shoot tissue using multiple chromatographic properties and mass spectral identification. The kernel and the seedling shoot both contain indole-3-acetyl-myo-inositol esters, and these esters comprise approximately the same percentage of the total ester content of the kernel and of the shoot.

  15. Isoquercitrin Esters with Mono- or Dicarboxylic Acids: Enzymatic Preparation and Properties.

    Science.gov (United States)

    Vavříková, Eva; Langschwager, Fanny; Jezova-Kalachova, Lubica; Křenková, Alena; Mikulová, Barbora; Kuzma, Marek; Křen, Vladimír; Valentová, Kateřina

    2016-06-07

    A series of isoquercitrin (quercetin-3-O-β-d-glucopyranoside) esters with mono- or dicarboxylic acids was designed to modulate hydro- and lipophilicity and biological properties. Esterification of isoquercitrin was accomplished by direct chemoenzymatic reaction using Novozym 435 (lipase from Candida antarctica), which accepted C₅- to C12-dicarboxylic acids; the shorter ones, such as oxalic (C₂), malonic (C₃), succinic (C₄) and maleic (C₄) acids were not substrates of the lipase. Lipophilicity of monocarboxylic acid derivatives, measured as log P, increased with the chain length. Esters with glutaric and adipic acids exhibited hydrophilicity, and the dodecanedioic acid hemiester was more lipophilic. All derivatives were less able to reduce Folin-Ciocalteau reagent (FCR) and scavenge DPPH (1,1-diphenyl-2-picrylhydrazyl) than isoquercitrin; ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) radical-scavenging activity was comparable. Dodecanoate and palmitate were the least active in FCR and ABTS scavenging; dodecanoate and hemiglutarate were the strongest DPPH scavengers. In contrast, most derivatives were much better inhibitors of microsomal lipoperoxidation than isoquercitrin; butyrate and hexanoate were the most efficient. Anti-lipoperoxidant activity of monocarboxylic derivatives, except acetates, decreased with increasing aliphatic chain. The opposite trend was noted for dicarboxylic acid hemiesters, isoquercitrin hemidodecanedioate being the most active. Overall, IQ butyrate, hexanoate and hemidodecanedioate are the most promising candidates for further studies.

  16. A green two-step process for adipic acid production from cyclohexene. A study on parameters affecting selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Cavani, F.; Macchia, F.; Pino, R.; Raabova, K.; Rozhko, E. [Bologna Univ. (Italy). Dipt. di Chimica Industriale e dei Materiali; Alini, S.; Accorinti, P.; Babini, G. [Radici Chimica SpA, Novara (Italy)

    2011-07-01

    In this paper, we report about the effect of reaction parameters on catalytic behavior in a twostep process aimed at the synthesis of adipic acid from cyclohexene. In the first step, cyclohexene reacts with an aqueous solution of hydrogen peroxide, under conditions leading to the formation of trans-1,2-cyclohexandiol as the prevailing product; the reaction is catalysed by tungstic acid, in the presence of phosphoric acid and of a PT agent. In the second step, 1,2-cyclohexandiol is oxidized with air, in the presence of an heterogeneous catalyst made of alumina-supported Ru(OH){sub 3}. This process is aimed at using the minimal amount of the costly hydrogen peroxide, since only one mole is theoretically needed per mole of cyclohexene. The first step afforded very high yield to the glycol, using only a slight excess of hydrogen peroxide. However, the second step turned out to be the more critical one, since the selectivity to adipic acid was very low because of the concomitant occurrence of several undesired side reactions. The latter were in part due to the reaction conditions used, which were necessary for the activation of cyclohexandiol. (orig.)

  17. Effect of Naphthalene, Butylated Hydroxytoluene, Dioctyl Phthalate, and Adipic Dioctyl Ester, Chemicals Found in the Nests of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae) on a Saprophytic Mucor sp.

    Science.gov (United States)

    Fungi are commonly found associated with termites and their nests. Four chemicals that have been isolated from the nests of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were evaluated to determine their effect on a common nest fungus, a saprophytic Mucor sp. Butylated hydroxyto...

  18. Novel electrospun nanofibrous matrices prepared from poly(lactic acid)/poly(butylene adipate) blends for controlled release formulations of an anti-rheumatoid agent.

    Science.gov (United States)

    Siafaka, Panoraia I; Barmbalexis, Panagiotis; Bikiaris, Dimitrios N

    2016-06-10

    In the present work, a series of novel formulations consisting of poly(lactic acid)/poly(butylene adipate) (PLA/PBAd) electrospun blends was examined as controlled release matrices for Leflunomide's active metabolite, Teriflunomide (TFL). The mixtures were prepared using different ratios of PLA and PBAd in order to produce nanofibrous matrices with different characteristics. Miscibility studies of the blended polymeric fibers were performed through differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). Hydrolytic degradation in the prepared fibers was evaluated at 37°C using a phosphate buffered saline solution. Different concentrations of (TFL) (5, 10, 15wt.%) were incorporated into nanofibers for examining the drug release behavior in simulated body fluids (SBF), at 37°C. The drug-loaded nanofibrous formulations were further characterized by Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, DSC and XRD. Gel permeation chromatography (GPC) analysis was used to evaluate the mechanism of TFL release. Artificial neural networks (ANN) and multi-linear-regression (MLR) models were used to evaluate the effect of % content of PBAd (X1) and TFL (X2) on an initial burst effect and a dissolution behavior. It was found that PLA/PBAd nanofibers have different diameters depending on the ratio of used polyesters and added drug. TFL was incorporated in an amorphous form inside the polymeric nanofibers. In vitro release studies reveal that a drug release behavior is correlated with the size of the nanofibers, drug loading and matrix degradation after a specific time. ANN dissolution modeling showed increased correlation efficacy compared to MLR. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Processing and characterization of recycled poly(ethylene terephthalate) blends with chain extenders, thermoplastic elastomer, and/or poly(butylene adipate-co-terephthalate)

    Science.gov (United States)

    Yottha Srithep; Alireza Javadi; Srikanth Pilla; Lih-Sheng Turng; Shaoqin Gong; Craig Clemons; Jun Peng

    2011-01-01

    Poly(ethylene terephthalate) (PET) resin is one of the most widely used thermoplastics, especially in packaging. Because thermal and hydrolytic degradations, recycled PET (RPET) exhibits poor mechanical properties and lacks moldability. The effects of adding elastomeric modifiers, chain extenders (CE), and poly(butylenes adipate-co-terephthalate), PBAT, as a toughener...

  20. Single-Atom Mn Active Site in a Triol-Stabilized β-Anderson Manganohexamolybdate for Enhanced Catalytic Activity towards Adipic Acid Production

    Directory of Open Access Journals (Sweden)

    Jianhui Luo

    2018-03-01

    Full Text Available Adipic acid is an important raw chemical for the commercial production of polyamides and polyesters. The traditional industrial adipic acid production utilizes nitric acid to oxidize KA oil (mixtures of cyclohexanone and cyclohexanol, leading to the emission of N2O and thus causing ozone depletion, global warming, and acid rain. Herein, we reported an organically functionalized β-isomer of Anderson polyoxometalates (POMs nanocluster with single-atom Mn, β-{[H3NC(CH2O3]2MnMo6O18}− (1, as a highly active catalyst to selectively catalyze the oxidation of cyclohexanone, cyclohexanol, or KA oil with atom economy use of 30% H2O2 for the eco-friendly synthesis of adipic acid. The catalyst has been characterized by single crystal and powder XRD, XPS, ESI-MS, FT-IR, and NMR. A cyclohexanone (cyclohexanol conversion of >99.9% with an adipic acid selectivity of ~97.1% (~85.3% could be achieved over catalyst 1 with high turnover frequency of 2427.5 h−1 (2132.5 h−1. It has been demonstrated that the existence of Mn3+ atom active site in catalyst 1 and the special butterfly-shaped topology of POMs both play vital roles in the enhancement of catalytic activity.

  1. Polystyrene/TiO2 composite electrospun fibers as fillers for poly(butylene succinate-co-adipate): Structure, morphology and properties

    CSIR Research Space (South Africa)

    Neppalli, R

    2014-01-01

    Full Text Available In this work, composite polystyrene/titanium dioxide (PS/TiO(sub2)) electrospun fibers were used as a reinforcement for a poly(butylene succinate-co-adipate) (PBSA) matrix. The structure, morphology, mechanical properties and degradation behavior...

  2. Effect of nanoclay loading on the thermal and mechanical properties of biodegradable Polylactide/Poly[(butylene succinate)- co-adipate] blend composites

    CSIR Research Space (South Africa)

    Ojijo, Vincent O

    2012-04-01

    Full Text Available Polylactide/poly[(butylene succinate)-co-adipate] (PLA/PBSA)-organoclay composites were prepared via melt compounding in a batch mixer. The weight ratio of PLA to PBSA was kept at 70:30, while the weight fraction of the organoclay was varied from 0...

  3. Catalytic Synthesis of Ethyl Ester From Some Common Oils ...

    African Journals Online (AJOL)

    Catalytic conversion of ethanol to fatty acid ethyl esters (FAEE) was carried out by homogeneous and heterogeneous transesterification of melon seed, shea butter and neem seed oils using NaOH, KOH and 5wt%CaO/Al2O3 catalyst systems respectively. Oil content of the seeds from n-hexane or hot water extract ranged ...

  4. Phthalate esters in marine algae

    OpenAIRE

    Gezgin, Tuncay; Güven, Kasim Cemal; Akçin, Göksel

    2001-01-01

    Abstract o-Phthalate esters as diethyl phthalate, dibutyl phthalate, di-isobutyl phthalate and diethylhexyl phthalate were identified at surface and inner part of algae collected in the Bosphorus, as Ulva lactuca, Enteromorpha linza, Cystoseria barbata, Pterocladia capillaceaeand Ceramium rubrum. The same esters were also detected in seawater samples taken from the same area. Thus parallelism in pollution was noted between the algae and the surrounding seawater,

  5. Association between content in serum in 2, 4-D butyl ester and behavior-intelligence quotient of children%儿童血清中2,4-D丁酯水平与行为、智力的关系

    Institute of Scientific and Technical Information of China (English)

    鲁彦; 祝丽玲; 姚嵩坡; 杜宁; 关宝生; 张艺滢; 张媛媛; 李美玲; 李京

    2013-01-01

    目的:探讨儿童血清中2,4-D丁酯与行为及智力的关系.方法:分层整群抽取黑龙江省某市农业发达的农村321例6~10岁儿童为研究对象,气相色谱法测定血清2,4-D丁酯含量,根据血清2,4-D丁酯浓度将儿童分为2,4-D丁酯低暴露组(<0.0345Jg/L)和2,4-D丁酯高暴露组 (≥0.0345μg/L),Conners儿童行为量表 (父母问卷)评价儿童行为,瑞文推理测验联合型(CRT)量表评价儿童智力.结果:在275名(85.67%)儿童血清中检出2,4-D丁酯(检出限0.0044 μg/L),59名(18.38%)儿童有行为问题.高暴露组行为问题总发生率高于低暴露组(P<0.05),高暴露组品行问题、学习困难、心身问题、行为问题发生率高于低暴露组(P<0.05),高暴露组智商(IQ)低于低暴露组(P<0.05);2,4-D丁酯含量与品行问题、学习困难、心身问题、冲动-多动行为因子评分呈正相关(P<0.05),与IQ值呈负相关(P<0.05).结论:2,4-D丁酯影响6~10岁儿童行为和智力.%Objective:To explore the association between the content of serum 2,4-D butyl ester and behavior-intelligence quotient of children.Methods:321 children aged 6-10 years old peasants were investigated with stratifler cluster sampling in rural developed areas in a city of Heilongjiang province.Content of 2,4-D butyl ester in serum was analyzed by gas chromatography.According to concentrations of 2,4-D butyl ester in serum were studied as lower exposure group (< 0.034 5μg/L) and higher exposure group (≥0.034 5 μg/L).Behaviors of children were evaluated by Conners Behavior Checklist questionnaire.Combined Raven's Test (CRT) are used to assess the children's intelligence quotient (IQ).Results:In the study,the 2,4-D butyl ester (detection limit 0.004 4 μg/L)were detected in serum of 275 (85.67%) children and 59 (18.38%) of them had behavior problems.The rates of behavior problem in high-exposure group was higher than those rates of behavior problem in low-exposure group (P

  6. Molecular and Supramolecular Changes in Polybutylene Succinate (PBS and Polybutylene Succinate Adipate (PBSA Copolymer during Degradation in Various Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Michał Puchalski

    2018-03-01

    Full Text Available In this paper, the influence of the various degradation conditions, on the molecular and supramolecular structure of polybutylene succinate (PBS and polybutylene succinate adipate (PBSA copolymer during degradation is described. The experiment was carried out by the use of injection molded samples and normalized conditions of biodegradation in soil, composting and artificial weathering. Materials were studied by size-exclusion chromatography (SEC coupled with multiangle laser light scattering (MALLS detection and wide-angle X-ray diffraction (WAXD. Additionally, the physical and mechanical properties of the samples were determined. The performed experiments clearly show difference impacts of the selected degradation conditions on the macroscopic, supramolecular and molecular parameters of the studied aliphatic polyesters. The structural changes in PBS and PBSA explain the observed changes in the physical and mechanical properties of the obtained injection molded samples.

  7. Effect of Anorganic Substance on Physical Properties of Poly (Butylene Succinate -co- Adipate) Irradiated by Electron Beam

    International Nuclear Information System (INIS)

    Meri Suhartini

    2004-01-01

    Poly(butylene succinate-co-adipate), PBSA were electron beam irradiated in the presence of inorganic materials. The samples gave high gel fraction by irradiation in the presence of 2% silicon dioxide and 2% carbon black. It was found that addition of carbon black (CB) was effective for improving the heat stability of the sample. This is because of three-dimensional carbon black- polymer networks. Irradiated PBSA sheets broke immediately at 110 o C with load 6.67 kgf/cm 2 , while irradiated the same sample mixed with 2% carbon black did not break at the same condition. Biodegradability of crosslinked PBSA by soil burial tests was accelerated by addition of carbon black. (author)

  8. Study of Non-Isothermal Crystallization Kinetics of Biodegradable Poly(ethylene adipate/SiO2 Nanocomposites

    Directory of Open Access Journals (Sweden)

    M. R. Memarzadeh

    2013-09-01

    Full Text Available Poly(ethylene adipte and poly(ethylene adipate/silica nanocomposite (PEAd/SiO2 containing 3 wt. % SiO2  were prepared by an in situ method. The examinations on the non-isothermal crystallization kinetic behavior have been conducted by means of differential scanning calorimeter (DSC. The Avrami, Ozawa, and combined Avrami and Ozawa equations were applied to describe the crystallization kinetics and to determine the crystallization parameters of the prepared PEAd/SiO2 nanocomposites. It is found that the inclusion of the silica nanoparticles can accelerate the nucleation rate due to heterogeneous nucleation effect of silica on the polymer matrix. According to the obtained results, the combined Avrami and Ozawa equation shown that the better model for examination of this system.

  9. Antiandrogenic effects in male rats perinatally exposed to a mixture of di(2-ethylhexyl) phthalate and di(2-ethylhexyl) adipate

    DEFF Research Database (Denmark)

    Jarfelt, K.; Dalgaard, M.; Hass, Ulla

    2005-01-01

    Di(2-ethylhexyl) phthalate (DEHP) is a well-known testicular toxicant inducing adverse effects in androgen responsive tissues. Therefore, di(2-ethylhexyl) adipate (DERA) is currently being evaluated as a potential substitute for DEHP. Similarities in structure and metabolism of DERP and DEHA have...... in the reproductive system than males receiving DERP alone. (c) 2004 Elsevier Inc. All rights reserved.......) and retention of nipples in male offspring were found in all three exposed groups. Dosed males exhibited decreased weights of ventral prostate and m. levator ani/bulbocavernosus. Histopathological investigations revealed alterations in testis morphology in both juvenile and adult animals. The litter size...... was decreased and postnatal mortality was increased in the combination group only, which is likely a combined effect of DEHP and DEHA. However, no combination effect was seen with respect to antiandrogenic effects, as males receiving DEHP in combination with DEHA did not exhibit more pronounced effects...

  10. Flow-induced crystallization of a nano composite of poly(butylene adipate-co-terephthalate)/montmorillonite

    International Nuclear Information System (INIS)

    Bonel, Alan B.; Rego, Bruna T.; Beatrice, Cesar A.G.; Marini, Juliano; Bretas, Rosario E.S.

    2011-01-01

    Poly(butylene adipate-co-terephthalate) (PBAT) with 5wt% of an organically modified montmorillonite with polar surfactant was prepared by melt blending in a co-rotational twin-screw extruder at 160 degree C. 100rpm and 1 kg/h. Both pure polymer and nano composite were characterized by wide measurements. The study of the flow-induced crystallization was also done by rheological measurements, monitoring the viscosity as a function of time. The nano clay's lamellas were intercalated in the polymer m loss moduli of the nano composite, at low frequencies, showed that the particles of the nano clay were well dispersed and distributed thru the PBAT matrix. Finally, the presence of the nano clay's particles reduced the induction tim crystals growth, due to the strong interactions with the PBAT chains. (author)

  11. Influence of the addition of bentonite clay in poli (butylene adipate co-terephthalic) / poly(lactic acid) membranes

    International Nuclear Information System (INIS)

    Morais, D.D.S.; Medeiros, K.M.; Araujo, E.M.; Melo, T.J.A.; Barbosa, R.

    2014-01-01

    The processes of membrane separation have been used in many different sectors of industrial activity, ranging from the chemical industry, food, pharmaceutical, medical and biotech. In this paper, a bentonite clay was added by melt intercalation in a poly(butylene adipate-co-terephthalic acid)/poly(lactic acid) blend at levels 1 and 3 wt% of clay. After that, membranes were produced by solvent evaporation technique. From the XRD results, it was verified the possible formation of exfoliated/partially exfoliated structures in the membranes. By DSC, it was observed that the addition of clay did not promote alterations in glass transition temperature and crystalline melting of the PBAT/PLA matrix. The morphology of the membranes were observed by SEM and it was verified the clay formation of porous membranes. (author)

  12. Preferential enrichment of large-sized very low density lipoprotein populations with transferred cholesteryl esters

    International Nuclear Information System (INIS)

    Eisenberg, S.

    1985-01-01

    The effect of lipid transfer proteins on the exchange and transfer of cholesteryl esters from rat plasma HDL2 to human very low (VLDL) and low density (LDL) lipoprotein populations was studied. The use of a combination of radiochemical and chemical methods allowed separate assessment of [ 3 H]cholesteryl ester exchange and of cholesteryl ester transfer. VLDL-I was the preferred acceptor for transferred cholesteryl esters, followed by VLDL-II and VLDL-III. LDL did not acquire cholesteryl esters. The contribution of exchange of [ 3 H]cholesteryl esters to total transfer was highest for LDL and decreased in reverse order along the VLDL density range. Inactivation of lecithin: cholesterol acyltransferase (LCAT) and heating the HDL2 for 60 min at 56 degrees C accelerated transfer and exchange of [ 3 H]cholesteryl esters. Addition of lipid transfer proteins increased cholesterol esterification in all systems. The data demonstrate that large-sized, triglyceride-rich VLDL particles are preferred acceptors for transferred cholesteryl esters. It is suggested that enrichment of very low density lipoproteins with cholesteryl esters reflects the triglyceride content of the particles

  13. Impact of thermooxidation of phytosteryl and phytostanyl fatty acid esters on cholesterol micellarization in vitro.

    Science.gov (United States)

    Scholz, Birgit; Weiherer, Renate; Engel, Karl-Heinz

    2017-09-01

    The effects of thermooxidation of a phytosteryl/-stanyl and a phytostanyl fatty acid ester mixture on cholesterol micellarization were investigated using an in vitro digestion model simulating enzymatic hydrolysis by cholesterol esterase and subsequent competition of the liberated phytosterols/-stanols with cholesterol for incorporation into mixed micelles. As a first step, relationships between different doses of the ester mixtures and the resulting micellarized cholesterol were established. Subsequent subjection of the thermooxidized ester mixtures to the in vitro digestion model resulted in three principal observations: (i) thermal treatment of the ester mixtures led to substantial decreases of the intact esters, (ii) in vitro digestion of cholesterol in the presence of the thermooxidized ester mixtures resulted in significant increases of cholesterol micellarization, and (iii) the extents of the observed effects on cholesterol micellarization were strongly associated to the remaining contents of intact esters. The loss of efficacy to inhibit cholesterol micellarization due to thermally induced losses of intact esters corresponded to a loss of efficacy that would have been induced by an actual removal of these amounts of esters prior to the in vitro digestion. The obtained results suggest that in particular oxidative modifications of the fatty acid moieties might be responsible for the observed increases of cholesterol micellarization. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. A Comparison Study: The New Extended Shelf Life Isopropyl Ester PMR Technology versus The Traditional Methyl Ester PMR Approach

    Science.gov (United States)

    Alston, William B.; Scheiman, Daniel A.; Sivko, Gloria S.

    2005-01-01

    Polymerization of Monomeric Reactants (PMR) monomer solutions and carbon cloth prepregs of PMR II-50 and VCAP-75 were prepared using both the traditional limited shelf life methanol based PMR approach and a novel extended shelf life isopropanol based PMR approach. The methyl ester and isopropyl ester based PMR monomer solutions and PMR prepregs were aged for up to four years at freezer and room temperatures. The aging products formed were monitored using high pressure liquid chromatography (HPLC). The composite processing flow characteristics and volatile contents of the aged prepregs were also correlated versus room temperature storage time. Composite processing cycles were developed and six ply cloth laminates were fabricated with prepregs after various extended room temperature storage times. The composites were then evaluated for glass transition temperature (Tg), thermal decomposition temperature (Td), initial flexural strength (FS) and modulus (FM), long term (1000 hours at 316 C) thermal oxidative stability (TOS), and retention of FS and FM after 1000 hours aging at 316 C. The results for each ester system were comparable. Freezer storage was found to prevent the formation of aging products for both ester systems. Room temperature storage of the novel isopropyl ester system increased PMR monomer solution and PMR prepreg shelf life by at least an order of magnitude while maintaining composite properties.

  15. Environmental effect of rapeseed oil ethyl ester

    International Nuclear Information System (INIS)

    Makareviciene, V.; Janulis, P.

    2003-01-01

    Exhaust emission tests were conducted on rapeseed oil methyl ester (RME), rapeseed oil ethyl ester (REE) and fossil diesel fuel as well as on their mixtures. Results showed that when considering emissions of nitrogen oxides (NO x ), carbon monoxide (CO) and smoke density, rapeseed oil ethyl ester had less negative effect on the environment in comparison with that of rapeseed oil methyl ester. When fuelled with rapeseed oil ethyl ester, the emissions of NO x showed an increase of 8.3% over those of fossil diesel fuel. When operated on 25-50% bio-ester mixed with fossil diesel fuel, NO x emissions marginally decreased. When fuelled with pure rapeseed oil ethyl ester, HC emissions decreased by 53%, CO emissions by 7.2% and smoke density 72.6% when compared with emissions when fossil diesel fuel was used. Carbon dioxide (CO 2 ) emissions, which cause greenhouse effect, decreased by 782.87 g/kWh when rapeseed oil ethyl ester was used and by 782.26 g/kWh when rapeseed oil methyl ester was used instead of fossil diesel fuel. Rapeseed oil ethyl ester was more rapidly biodegradable in aqua environment when compared with rapeseed oil methyl ester and especially with fossil diesel fuel. During a standard 21 day period, 97.7% of rapeseed oil methyl ester, 98% of rapeseed oil ethyl ester and only 61.3% of fossil diesel fuel were biologically decomposed. (author)

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

    Science.gov (United States)

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

    2009-01-01

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

  17. Orally administered glycidol and its fatty acid esters as well as 3-MCPD fatty acid esters are metabolized to 3-MCPD in the F344 rat.

    Science.gov (United States)

    Onami, Saeko; Cho, Young-Man; Toyoda, Takeshi; Akagi, Jun-ichi; Fujiwara, Satoshi; Ochiai, Ryosuke; Tsujino, Kazushige; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2015-12-01

    IARC has classified glycidol and 3-monochloropropane-1,2-diol (3-MCPD) as group 2A and 2B, respectively. Their esters are generated in foodstuffs during processing and there are concerns that they may be hydrolyzed to the carcinogenic forms in vivo. Thus, we conducted two studies. In the first, we administered glycidol and 3-MCPD and associated esters (glycidol oleate: GO, glycidol linoleate: GL, 3-MCPD dipalmitate: CDP, 3-MCPD monopalmitate: CMP, 3-MCPD dioleate: CDO) to male F344 rats by single oral gavage. After 30 min, 3-MCPD was detected in serum from all groups. Glycidol was detected in serum from the rats given glycidol or GL and CDP and CDO in serum from rats given these compounds. In the second, we examined if metabolism occurs on simple reaction with rat intestinal contents (gastric, duodenal and cecal contents) from male F344 gpt delta rats. Newly produced 3-MCPD was detected in all gut contents incubated with the three 3-MCPD fatty acid esters and in gastric and duodenal contents incubated with glycidol and in duodenal and cecal contents incubated with GO. Although our observation was performed at 1 time point, the results showed that not only 3-MCPD esters but also glycidol and glycidol esters are metabolized into 3-MCPD in the rat. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Mechanical properties and chemical stability of pivalolactone-based poly(ether ester)s

    NARCIS (Netherlands)

    Tijsma, E.J.; Tijsma, E.J.; van der Does, L.; Bantjes, A.; Bantjes, A.; Vulic, I.

    1994-01-01

    The processing, mechanical and chemical properties of poly(ether ester)s, prepared from pivalolactone (PVL), 1,4-butanediol (4G) and dimethyl terephthalate (DMT), were studied. The poly(ether ester)s could easily be processed by injection moulding, owing to their favourable rheological and thermal

  19. Synthesis of oleyl oleate wax esters in Arabidopsis thaliana and Camelina sativa seed oil.

    Science.gov (United States)

    Iven, Tim; Hornung, Ellen; Heilmann, Mareike; Feussner, Ivo

    2016-01-01

    Seed oil composed of wax esters with long-chain monoenoic acyl moieties represents a high-value commodity for industry. Such plant-derived sperm oil-like liquid wax esters are biodegradable and can have excellent properties for lubrication. In addition, wax ester oil may represent a superior substrate for biodiesel production. In this study, we demonstrate that the low-input oil seed crop Camelina sativa can serve as a biotechnological platform for environmentally benign wax ester production. Two biosynthetic steps catalysed by a fatty alcohol-forming acyl-CoA reductase (FAR) and a wax ester synthase (WS) are sufficient to achieve wax ester accumulation from acyl-CoA substrates. To produce plant-derived sperm oil-like liquid wax esters, the WS from Mus musculus (MmWS) or Simmondsia chinensis (ScWS) were expressed in combination with the FAR from Mus musculus (MmFAR1) or Marinobacter aquaeolei (MaFAR) in seeds of Arabidopsis thaliana and Camelina sativa. The three analysed enzyme combinations Oleo3:mCherry:MmFAR1∆c/Oleo3:EYFP:MmWS, Oleo3:mCherry:MmFAR1∆c/ScWS and MaFAR/ScWS showed differences in the wax ester molecular species profiles and overall biosynthetic performance. By expressing MaFAR/ScWS in Arabidopsis or Camelina up to 59% or 21% of the seed oil TAGs were replaced by wax esters, respectively. This combination also yielded wax ester molecular species with highest content of monounsaturated acyl moieties. Expression of the enzyme combinations in the Arabidopsis fae1 fad2 mutant background high in oleic acid resulted in wax ester accumulation enriched in oleyl oleate (18:1/18:1 > 60%), suggesting that similar values may be obtained with a Camelina high oleic acid line. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  20. REPRODUCTIVE TOXICITY OF PHTHALATE ESTERS

    Science.gov (United States)

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

  1. Regioselective Synthesis of Cellulose Ester Homopolymers

    Science.gov (United States)

    Daiqiang Xu; Kristen Voiges; Thomas Elder; Petra Mischnick; Kevin J. Edgar

    2012-01-01

    Regioselective synthesis of cellulose esters is extremely difficult due to the small reactivity differences between cellulose hydroxyl groups, small differences in steric demand between acyl moieties of interest, and the difficulty of attaching and detaching many protecting groups in the presence of cellulose ester moieties without removing the ester groups. Yet the...

  2. Ionic liquids as surfactants for layered double hydroxide fillers: effect on the final properties of poly(butylene adipate-co-terephthalate)

    Czech Academy of Sciences Publication Activity Database

    Livi, S.; Lins, L. C.; Peter, Jakub; Beneš, Hynek; Kredatusová, Jana; Donato, R. K.; Pruvost, S.

    2017-01-01

    Roč. 7, č. 10 (2017), s. 1-16, č. článku 297. ISSN 2079-4991 R&D Projects: GA ČR(CZ) GA17-08273S Institutional support: RVO:61389013 Keywords : ionic liquids * poly(butylene adipate-co-terephthalate) * layered double hydroxide Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 3.553, year: 2016

  3. Isolation, Fractionation, and Identification of Sucrose Esters from Various Oriental Tobaccos Employing Supercritical Fluids

    Directory of Open Access Journals (Sweden)

    Ashraf-Khorassani M

    2014-12-01

    Full Text Available Isolation, fractionation, and identification of sucrose esters from aged oriental tobacco employing supercritical fluids have been completed. Underivatized sucrose ester-rich extracts were obtained using supercritical CO2 at densities greater than 0.73 g/mL. Lower density CO2 provided extracts with notable amounts of tobacco derived material; yet, no detectable sucrose ester content. Preparative supercritical fluid chromatography (SFC provided for an additional purification of the sucrose ester-enriched fraction after column optimization. Structural assignments of the SFC fractions were facilitated using gas chromatography/mass spectrometry (GC/MS accompanied by N, O-bis(trimethylsilyltrifluoroacetamide-dimethylformamide (BSTFA-DMF derivatization of the free hydroxyl groups and high performance-liquid chromatography/mass spectrometry (HPLC/MS. From a relative quantitative perspective regardless of tobacco type, sucrose esters having an acetyl group on C6 of the glucose function (Group III were in higher concentration compared to both the concentration observed for sucrose ester of Group I (acetyl group on C3 of fructose and sucrose ester of Group II (no acetyl group on either glucose or fructose. Saturated fatty acid constituents were found to range from a maximum total of 18 carbons to a minimum total of 13 carbons. Unsaturated and isomeric fatty acid homologues were detected within the Group II sucrose ester.

  4. Supramolecular architecture in a co-crystal of the N(7—H tautomeric form of N6-benzoyladenine with adipic acid (1/0.5

    Directory of Open Access Journals (Sweden)

    Robert Swinton Darious

    2016-06-01

    Full Text Available The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one molecule of N6-benzoyladenine (BA and one half-molecule of adipic acid (AA, the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7°. The N6-benzoyladenine molecule crystallizes in the N(7—H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intramolecular N—H...O hydrogen bonding between the carbonyl (C=O group and the N(7—H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7 ring motif. The two carboxyl groups of adipic acid interact with the Watson–Crick face of the BA molecules through O—H...N and N—H...O hydrogen bonds, generating an R22(8 ring motif. The latter units are linked by N—H...N hydrogen bonds, forming layers parallel to (10-5. A weak C—H...O hydrogen bond is also present, linking adipic acid molecules in neighbouring layers, enclosing R22(10 ring motifs and forming a three-dimensional structure. C=O...π and C—H...π interactions are also present in the structure.

  5. Catalytic Ester to Stannane Functional Group Interconversion via Decarbonylative Cross-Coupling of Methyl Esters

    KAUST Repository

    Yue, Huifeng

    2018-01-03

    An unprecedented conversion of methyl esters to stannanes was realized, providing access to a series of arylstannanes via nickel catalysis. Various common esters including ethyl, cyclohexyl, benzyl, and phenyl esters can undergo the newly developed decarbonylative stannylation reaction. The reaction shows broad substrate scope, can differentiate between different types of esters, and if applied in consecutive fashion, allows the transformation of methyl esters into aryl fluorides or biaryls via fluororination or arylation.

  6. Catalytic Ester to Stannane Functional Group Interconversion via Decarbonylative Cross-Coupling of Methyl Esters

    KAUST Repository

    Yue, Huifeng; Zhu, Chen; Rueping, Magnus

    2018-01-01

    An unprecedented conversion of methyl esters to stannanes was realized, providing access to a series of arylstannanes via nickel catalysis. Various common esters including ethyl, cyclohexyl, benzyl, and phenyl esters can undergo the newly developed decarbonylative stannylation reaction. The reaction shows broad substrate scope, can differentiate between different types of esters, and if applied in consecutive fashion, allows the transformation of methyl esters into aryl fluorides or biaryls via fluororination or arylation.

  7. Production and characterization of novel starch and poly(butylene adipate-co-terephthalate)-based materials and their applications

    Science.gov (United States)

    Stagner, Jacqueline Ann

    This work focuses on the production and characterization of blends of maleated thermoplastic starch (MTPS) and poly(butylenes adipate-co-terephthalate) and their application for use as thermoformed objects, films, and foams. First, by the production and characterization of maleated thermoplastic starch (MTPS) synthesized by reactive extrusion in a twin-screw extruder, a better understanding of MTPS was gained. This reactive thermoplastic starch was prepared with glycerol as the plasticizer, maleic anhydride (MA), and free-radical initiator, 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane (Luperox 101). Dynamic light scattering (DLS), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), soxhlet extraction in acetone, and environmental scanning electron microscopy (ESEM) were performed to determine the effect of maleation, extrusion temperature, initiator concentration, and maleic anhydride concentration on the resulting MTPS. Next, maleated thermoplastic starch (MTPS) and thermoplastic starch (TPS) were reactively blended in a twin-screw extruder with a biodegradable polyester, poly(butylene adipate-co-terephthalate) (PBAT). The blends were extruded to produce thermoformable sheets. The mechanical properties of the sheets were characterized by tensile and puncture tests. Proof of grafting was determined by soxhlet extraction in dichloromethane and FTIR analysis. Observations of the thermal properties were made using DSC, while the surface of the sheets was imaged using ESEM. Blends of MTPS and PBAT were also extruded to produce films. Mechanical testing (tensile and puncture tests) and barrier performance testing (carbon dioxide, oxygen, and water vapor permeability) were performed on the films. Transmission electron microscopy (TEM) was used to image the blends and to view the dispersion of the various phases. Finally, blends of MTPS and PBAT were extruded with an endothermic chemical blowing agent to produce foams. The foams were

  8. Lipase-Catalyzed Synthesis of Sugar Esters in Honey and Agave Syrup

    Directory of Open Access Journals (Sweden)

    Sascha Siebenhaller

    2018-02-01

    Full Text Available Honey and agave syrup are high quality natural products and consist of more than 80% sugars. They are used as sweeteners, and are ingredients of cosmetics or medical ointments. Furthermore, both have low water content, are often liquid at room temperature and resemble some known sugar-based deep eutectic solvents (DES. Since it has been shown that it is possible to synthesize sugar esters in these DESs, in the current work honey or, as vegan alternative, agave syrup are used simultaneously as solvent and substrate for the enzymatic sugar ester production. For this purpose, important characteristics of the herein used honey and agave syrup were determined and compared with other available types. Subsequently, an enzymatic transesterification of four fatty acid vinyl esters was accomplished in ordinary honey and agave syrup. Notwithstanding of the high water content for transesterification reactions of the solvent, the successful sugar ester formation was proved by thin-layer chromatography (TLC and compared to a sugar ester which was synthesized in a conventional DES. For a clear verification of the sugar esters, mass determinations by ESI-Q-ToF experiments and a NMR analysis were done. These environmentally friendly produced sugar esters have the potential to be used in cosmetics or pharmaceuticals, or to enhance their effectiveness.

  9. Lipase-Catalyzed Synthesis of Sugar Esters in Honey and Agave Syrup

    Science.gov (United States)

    Siebenhaller, Sascha; Gentes, Julian; Infantes, Alba; Muhle-Goll, Claudia; Kirschhöfer, Frank; Brenner-Weiß, Gerald; Ochsenreither, Katrin; Syldatk, Christoph

    2018-02-01

    Honey and agave syrup are high quality natural products and consist of more than 80% sugars. They are used as sweeteners, and are ingredients of cosmetics or medical ointments. Furthermore, both have low water content, are often liquid at room temperature and resemble some known sugar-based deep eutectic solvents. Since it has been shown that it is possible to synthesize sugar esters in these deep eutectic solvents, in the current work honey or, as vegan alternative, agave syrup are used simultaneously as solvent and substrate for the enzymatic sugar ester production. For this purpose, important characteristics of the herein used honey and agave syrup were determined and compared with other available types. Subsequently, an enzymatic transesterification of four fatty acid vinyl esters was accomplished in ordinary honey and agave syrup. Notwithstanding of the high water content for transesterification reactions of the solvent, the successful sugar ester formation was proved by thin-layer chromatography and compared to a sugar ester which was synthesized in a conventional deep eutectic solvent. For a clear verification of the sugar esters, mass determinations by ESI-Q-ToF experiments and a NMR analysis were done. These environmentally friendly produced sugar esters have the potential to be used in cosmetics or pharmaceuticals, or to enhance their effectiveness.

  10. Formation and reduction of 3-monochloropropane-1,2-diol esters in peanut oil during physical refining.

    Science.gov (United States)

    Li, Chang; Li, Linyan; Jia, Hanbing; Wang, Yuting; Shen, Mingyue; Nie, Shaoping; Xie, Mingyong

    2016-05-15

    In the present study, lab-scale physical refining processes were investigated for their effects on the formation of 3-monochloropropane-1,2-diol (3-MCPD) esters. The potential precursors, partial acylglycerols and chlorines were determined before each refining step. 3-MCPD esters were not detected in degummed and bleached oil when the crude oils were extracted by solvent. While in the hot squeezed crude oils, 3-MCPD esters were detected with low amounts. 3-MCPD esters were generated with maximum values in 1-1.5h at a certain deodorizing temperature (220-260°C). Chlorine seemed to be more effective precursor than partial acylglycerol. By washing bleached oil before deodorization with ethanol solution, the precursors were removed partially and the content of 3-MCPD esters decreased to some extent accordingly. Diacetin was found to reduce 3-MCPD esters effectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Biodegradability of poly(butylene succinate-co-butylene adipate) (PBSA) controlled by temperature during the dried-gel process

    Science.gov (United States)

    Yamazaki, Hana; Maeda, Tomoki; Hotta, Atsushi

    Currently there is a growing interest in biodegradable plastics that can be readily degraded into H2O and CO2. Among them, poly(butylene succinate-co-butylene adipate)(PBSA) is one of the mechanically attractive materials that can be biodegraded by surrounding water molecules and microorganisms after the disposal of the plastics. In order to expand the use of PBSA, the proper and effective control of the biodegradability of PBSA should be realized. In this work, the dried-gel process of the PBSA was carefully studied considering the temperature of the process. Three different types of dried PBSA gels were prepared at three different gel-process temperatures. From the biodegradability testing by immersing the PBSA samples in NaOH aq., it was found that the percentage of the weight loss of the PBSA was increased, indicating that the biodegradability was enhanced as the gel preparation temperature became lower. In fact, smaller spherocrystals were observed in PBSA dried at cooler temperature, studied by the scanning electron microscopy (SEM). It was therefore concluded that the microstructures of PBSA could be well controlled by changing the gel preparation temperatures for the precise control of the biodegradability of PBSA. This work was supported by a Grant-in-Aid for Scientific Research (A) (No. 15H02298 to A.H.) and a Grant-in-Aid for Research Activity Start-up (No.15H06586 to T.M.) from JSPS: KAKENHI\\x9D.

  12. Effect of organo-modified montmorillonite on poly(butylene succinate/poly(butylene adipate-co-terephthalate nanocomposites

    Directory of Open Access Journals (Sweden)

    2010-07-01

    Full Text Available The composite material based on poly(butylene succinate (PBS, poly(butylene adipate-co-terephthalate (PBAT and organo-modified montmorillonite (OMMT were prepared by melt blending technique and characterized. Sodium montmorillonite (Na-MMT was successfully modified by octadecylammonium (ODA and dimethyldioctadecylammonium (DDOA salts to become OMMT through cation exchange technique which is shown by the increase of basal spacing of clay by XRD. The addition of the OMMT to the PBS/PBAT blends produced nanocomposites which is proved by XRD and TEM. Tensile tests showed increase in tensile strength and modulus which is attributed to the existence of strong interactions between PBS/PBAT and clay, particularly with OMMT. Highest tensile strength of nanocomposite was observed at 1 wt% of OMMT incorporated. TGA study showed that the thermal stability of the blend increased after the addition of clays. SEM micrographs of the fracture surfaces show that the morphology of the blend becomes homogeneous and smoother with presence of OMMT.

  13. Structure and properties of Al-MIL-53-ADP, a breathing MOF based on the aliphatic linker molecule adipic acid.

    Science.gov (United States)

    Reinsch, Helge; Pillai, Renjith S; Siegel, Renée; Senker, Jürgen; Lieb, Alexandra; Maurin, Guillaume; Stock, Norbert

    2016-03-14

    The new aluminium based metal-organic framework [Al(OH)(O2C-C4H8-CO2)]·H2O denoted as Al-MIL-53-ADP-lp (lp stands for large pore) was synthesised under solvothermal conditions. This solid is an analogue of the archetypical aluminium terephthalate Al-MIL-53 based on the aliphatic single-chain linker molecule adipic acid (H2ADP, hexanedioic acid). In contrast to its aromatic counterparts, Al-MIL-53-ADP exhibits a structural breathing behaviour solely upon dehydration/rehydration. The crystal structure of the anhydrous compound denoted as Al-MIL-53-ADP-np (np stands for narrow pore) was determined by a combination of forcefield-based computations and Rietveld refinement of the powder X-ray diffraction data while the structure of the hydrated form Al-MIL-53-ADP-lp was derived computationally by a combination of force field based methods and Density Functional Theory calculations. Both structures were further supported by (1)H, (13)C and (27)Al high-resolution NMR MAS 1D data coupled again with simulations. Al-MIL-53-ADP was further characterised by means of vibrational spectroscopy, elemental analysis, thermogravimetry and water vapour sorption.

  14. KARAKTERISTIK EMULSI SANTAN DAN MINYAK KEDELAI YANG DITAMBAH GUM ARAB DAN SUKROSA ESTER [Emulsion Characteristics of Coconut Milk and Soybean Oil Added with Gum Arabic and Sucrose Ester

    Directory of Open Access Journals (Sweden)

    Laksmi Hartayanie

    2015-07-01

    Full Text Available High saturated fatty acid content in coconut milk can be reduced by adding unsaturated fat. Pretreatment such as pasteurisation, homogenization or stabilizer and emulsifier addition are essential to prevent emulsion deterioration that could happen in few hours. This study aimed to determine the most appropriate combination of gum arabic and sucrose ester to produce good emulsion stability based on its physical and chemical characteristics. Furthermore this study also aimed to determine correlation between creaming index and other characteristics of coconut milk emulsion. Emulsion stability of mixed coconut milk in sterile glass bottles was observed for 7 days under 23-24°C. Stabilizer and emulsifier added were gum arabic and sucrose ester in five combinations, i.e. 6% gum arabic, 0.3% sucrose ester, 6% gum arabic + 0.3% sucrose ester, 3% gum arabic + 0.15% sucrose ester and 4.5% gum arabic + 0.225% sucrose ester. The physical characteristics evaluated were creaming index, total color change, viscosity and droplet distribution, while the chemical characteristics observed included pH, TBA value, and protein content. Data were analyzed by One Way Anova at 95% significant level to determine the differences among treatments. Bivariate Pearson Correlation was used in order to determine the interaction among sample characteristics. The data showed that, gum arabic and sucrose ester can maintain the emulsion stability. A combination of 4.5% gum arabic and 0.225% sucrose ester provided the best physicochemical characteristics with the lowest creaming index and decreased viscosit, and uniform droplet distribution.

  15. Effect of sugar fatty acid esters on rumen fermentation in vitro

    OpenAIRE

    Wakita, M.; Hoshino, S.

    1987-01-01

    1.The effect of sugar fatty acid esters (SFEs; currently used as food additives for human consumption) on rumen volatile fatty acids (VFA) and gas production was studied with sheep rumen contents in vitro.2. Some SFEs having monoester contents of more than 70% increased the molar proportion of propionate in conjunction with reduction in the acetate: propionate ratio when the individual SFE was added to rumen contents in a final concentration of 4 g/l. Laurate sugar ester was the most potent p...

  16. Mechanism of formation of 3-chloropropan-1,2-diol (3-MCPD) esters under conditions of the vegetable oil refining.

    Science.gov (United States)

    Šmidrkal, Jan; Tesařová, Markéta; Hrádková, Iveta; Berčíková, Markéta; Adamčíková, Aneta; Filip, Vladimír

    2016-11-15

    3-MCPD esters are contaminants that can form during refining of vegetable oils in the deodorization step. It was experimentally shown that their content in the vegetable oil depends on the acid value of the vegetable oil and the chloride content. 3-MCPD esters form approximately 2-5 times faster from diacylglycerols than from monoacylglycerols. It has been proved that the higher fatty acids content in the oil caused higher 3-MCPD esters content in the deodorization step. Neutralization of free fatty acids in the vegetable oil before the deodorization step by alkaline carbonates or hydrogen carbonates can completely suppress the formation of 3-MCPD esters. Potassium salts are more effective than sodium salts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effects of Blending Alcohols with Poultry Fat Methyl Esters on Cold Flow Properties

    Science.gov (United States)

    The low temperature operability, kinematic viscosity, and acid value of poultry fat methyl esters were improved with addition of ethanol, isopropanol, and butanol in a linear fashion with increasing alcohol content. The flash point decreased and moisture content increased upon addition of alcohols t...

  18. Morphology and mechanical properties of poly(butylene adipate-co-terephthalate)/potato starch blends in the presence of synthesized reactive compatibilizer or modified poly(butylene adipate-co-terephthalate).

    Science.gov (United States)

    Wei, Dafu; Wang, Hao; Xiao, Huining; Zheng, Anna; Yang, Yang

    2015-06-05

    The biodegradable poly(butylene adipate-co-terephthalate)(PBAT)/thermoplastic starch (TPS) composite has received considerable attention because of the environmental concerns raised by solid waste disposal. However, the application of PBAT/TPS blends was limited due to the poor mechanical properties originating from the incompatibility between PBAT and TPS. In this work, two approaches were developed to improve the mechanical properties of PBAT/TPS blends. One approach is to use compatibilizers, including the synthesized reactive compatibilizer - a styrene-maleic anhydride-glycidyl methacrylate (SMG) terpolymer, and the commercial compatibilizer (Joncryl-ADR-4368). The chemical structures of SMG were analyzed with (1)H NMR and FT-IR. The other approach is to use the modified PBAT (M-PBAT) to replace part of PBAT in the PBAT/TPS blends. M-PBATs with higher molecular weight were obtained via reactive extrusion of PBAT in the presence of a chain extender. The better dispersion of TPS in PBAT was observed in SEM images when using M-PBAT, leading to the higher tensile strength and elongation at break of PBAT/TPS blends. However, the elongation at break decreased in the presence of compatibilizer (SMG or 4368), though the tensile strength remained in a similar level or slightly higher. Overall, the tensile strength and the elongation at break of the resulting biodegradable PBAT/M-PBAT/TPS blends (TPS=40wt%) were above 27.0MPa and 500%, respectively, which is promising for various applications, including packaging and agricultural mulching films. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. γ-Glutamyl semialdehyde and 2-amino-adipic semialdehyde: biomarkers of oxidative damage to proteins

    DEFF Research Database (Denmark)

    Daneshvar, B.; Frandsen, H.; Autrup, Herman

    1997-01-01

    proteins collected from eight different mammalian species was found to be inversely proportional to their maximum lifespan potential. The content of AAS in plasma proteins of untreated adult rats showed a positive correlation with the age of the rat. In young rats a negative correlation with age was found......Reactive oxygen species are formed in the body by several natural processes and by induced oxidative stress. The reactive oxygen species may react with the various biomolecules of the body, including proteins. In order to assess the impact of oxidative damage to proteins, we have tried to identify...

  20. New Insights on Degumming and Bleaching Process Parameters on The Formation of 3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters in Refined, Bleached, Deodorized Palm Oil.

    Science.gov (United States)

    Sim, Biow Ing; Muhamad, Halimah; Lai, Oi Ming; Abas, Faridah; Yeoh, Chee Beng; Nehdi, Imededdine Arbi; Khor, Yih Phing; Tan, Chin Ping

    2018-04-01

    This paper examines the interactions of degumming and bleaching processes as well as their influences on the formation of 3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters in refined, bleached and deodorized palm oil by using D-optimal design. Water degumming effectively reduced the 3-MCPDE content up to 50%. Acid activated bleaching earth had a greater effect on 3-MCPDE reduction compared to natural bleaching earth and acid activated bleaching earth with neutral pH, indicating that performance and adsorption capacities of bleaching earth are the predominant factors in the removal of esters, rather than its acidity profile. The combination of high dosage phosphoric acid during degumming with the use of acid activated bleaching earth eliminated almost all glycidyl esters during refining. Besides, the effects of crude palm oil quality was assessed and it was found that the quality of crude palm oil determines the level of formation of 3-MCPDE and glycidyl esters in palm oil during the high temperature deodorization step of physical refining process. Poor quality crude palm oil has strong impact towards 3-MCPDE and glycidyl esters formation due to the intrinsic components present within. The findings are useful to palm oil refining industry in choosing raw materials as an input during the refining process.

  1. Ester Tuiksoo. Proua Suhkru kibedad päevad / Ester Tuiksoo ; interv. Piret Tali

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2005-01-01

    Põllumajandusminister Ester Tuiksoo, kellel peagi täitub ministri ametis aasta Euroopa Liidu suhkrutrahvist, maaettevõtlusest, põllumajandusest, Euroopa Liidu toetustest, ministri elu- ja teenistuskäigust. Lisa: Ester Tuiksoo

  2. Method of making a cyanate ester foam

    Science.gov (United States)

    Celina, Mathias C.; Giron, Nicholas Henry

    2014-08-05

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

  3. Semi-Batch Reactive Distillation of Consecutive Reaction : The Saponification Reaction of Diethyl Adipate with Sodium Hydroxide Solution

    Directory of Open Access Journals (Sweden)

    Raghad Fareed Kasim

    2016-03-01

    Full Text Available This research presents a new study in reactive distillation by using consecutive reaction: the saponification reaction of diethyl adipate (DA with sodium hydroxide solution . The effect of three parameters were studied through a design of experiments applying 23 factorial design . These parameters were : the mole ratio of DA to NaOH solution (0.1 and 1 , NaOH solution concentration (3 N and 8 N , and batch time (1.5 hr. and 3.5 hr. . The conversion of DA to sodium monoethyladipate(SMA(intermediate product was the effect of these parameters which was detected . Also , the percentage purity of the intermediate product was recorded . The results showed that increasing mole ratio of DA to NaOHsolution increases the conversion and percentage purity to a maximum value within the range of study . The effect of NaOH solution concentration decreases the conversion and percentage purity to specified value within the range of study . The effect of batch time on conversion and percentage purity , when NaOH solution concentration (3 N is as follows : the increasing in batch time decreases the conversion and percentage purity to specified value within the range of study . When NaOH solution concentration (8 N increasing batch time decreases the conversion , while percentage purity increases with increasing batch time to a maximum value within the range of study . The maximum attainable conversion within the studied range of parameters was eighteen fold of the base case , while the maximum percentage purity was (99.40 % . Empirical equation was obtained using statistical analysis of experimental results . The empirical results of relative conversion was drawn . The empirical graphs showed linear variation .

  4. Identification and dosage by HRGC of minor alcohol and esters in Brazilian sugar-cane spirit

    International Nuclear Information System (INIS)

    Boscolo, Mauricio; Bezerra, Cicero W.B.; Cardoso, Daniel R.; Lima Neto, Benedito S.; Franco, Douglas W.

    2000-01-01

    The presence of 51 volatile compounds, among alcohols and esters in Brazilian sugar-cane spirit (cachaca), were investigated by high-resolution gas chromatography (HRGC). The following alcohols and esters were identified and quantified: methanol, 1,4-butanodiol, 2-phenylethyl alcohol, amyl alcohol, cetyl alcohol, cynamic alcohol, n-decanol, geraniol, isoamyl alcohol, isobutanol, menthol, n-butanol, n-dodecanol, n-propanol, n-tetradecanol, amyl propionate, ethyl acetate, ethyl benzoate, ethyl heptanoate, isoamyl valerate, methyl propionate, propyl butyrate. The average higher alcohols content (262 mg/100 mL in anhydrous alcohol a.a) and total esters content (24 mg/100 mL a.a) in cachacas, are smaller than in other spirits. The average methanol content in cachacas (6 mg/100 mL a.a) is the same as in rum, but smaller than in wine spirit. No qualitative differences of chemical profile among cachacas have been observed. (author)

  5. Identification and dosage by HRGC of minor alcohol and esters in Brazilian sugar-cane spirit

    Energy Technology Data Exchange (ETDEWEB)

    Boscolo, Mauricio; Bezerra, Cicero W.B.; Cardoso, Daniel R.; Lima Neto, Benedito S.; Franco, Douglas W. [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Quimica

    2000-02-01

    The presence of 51 volatile compounds, among alcohols and esters in Brazilian sugar-cane spirit (cachaca), were investigated by high-resolution gas chromatography (HRGC). The following alcohols and esters were identified and quantified: methanol, 1,4-butanodiol, 2-phenylethyl alcohol, amyl alcohol, cetyl alcohol, cynamic alcohol, n-decanol, geraniol, isoamyl alcohol, isobutanol, menthol, n-butanol, n-dodecanol, n-propanol, n-tetradecanol, amyl propionate, ethyl acetate, ethyl benzoate, ethyl heptanoate, isoamyl valerate, methyl propionate, propyl butyrate. The average higher alcohols content (262 mg/100 mL in anhydrous alcohol a.a) and total esters content (24 mg/100 mL a.a) in cachacas, are smaller than in other spirits. The average methanol content in cachacas (6 mg/100 mL a.a) is the same as in rum, but smaller than in wine spirit. No qualitative differences of chemical profile among cachacas have been observed. (author)

  6. Triphenyltin derivatives of sulfanylcarboxylic esters.

    Science.gov (United States)

    Casas, José S; Couce, María D; Sánchez, Agustín; Seoane, Rafael; Sordo, José; Perez-Estévez, Antonio; Vázquez-López, Ezequiel

    2018-03-01

    The reaction of 3-(aryl)-2-sulfanylpropenoic acids [H 2 xspa; x: p=3-phenyl-, f=3-(2-furyl)-, t=3-(2-thienyl)-] with methanol or ethanol gave the corresponding methyl (Hxspme) or ethyl (Hxspee) esters. The reaction of these esters (HL) with triphenyltin(IV) hydroxide gave compounds of the type [SnPh 3 L], which were isolated and characterized as solids by elemental analysis, IR spectroscopy and mass spectrometry and in solution by multinuclear ( 1 H, 13 C and 119 Sn) NMR spectroscopy. The structures of [SnPh 3 (pspme)], [SnPh 3 (fspme)] and [SnPh 3 (fspee)] were determined by X-ray diffractometry and the antimicrobial activity against E. coli, S. aureus, B. subtilis, P. aeruginosa, Resistant P. aeruginosa (a strain resistant to 'carbapenem'), and C. albicans was tested and the in vitro cytotoxic activity against the HeLa-229, A2780 and A2780cis cell lines was determined for all compounds. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Preparation of Spirocyclic β-Proline Esters

    DEFF Research Database (Denmark)

    Fjelbye, Kasper; Marigo, Mauro; Clausen, Rasmus Prætorius

    2017-01-01

    A series of novel N-Bn-protected spirocyclic β-proline esters were prepared using [3+2] cycloaddition and subsequently converted into their corresponding aldehydes. In addition, two novel N-Cbz-protected spirocyclic β-proline esters were prepared using intramolecular cyclization starting from...

  8. Anticholinesterase activity of fluorochloronitroacetic acid esters

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Yu.Ya.; Brel, V.K. Martynov, I.V.

    1984-11-01

    Results are presented from pharmacologic and biochemical experiments leading to the conclusion that fluorochloronitroacetic acid esters have anticholinesterase activity. Since the esters caused muscular weakness in mice, experiments were performed on isolated tissue preparation. The biochemical experiments consisted of finding the biomolecular constants of irreversible inhibition of acetylcholinesterase by the esters, using acetylcholinesterase from human erythrocytes, as well as horse serum cholinesterase. The ethyl and n-propyl esters of halogen nitroacetic acid were used in all experiments. It was found that the propyl ester caused an increase in the force of individual contractions in the isolated muscle specimens, plus an inability of the muscle to retain tetanus. The substances were determined to have an anticholinesterase effect. The mechanism of cholinesterase inhibition is not yet known. It is probable that the substances acylate the serine hydroxyl of the esterase center of the cholinestersase. 7 references, 1 figure.

  9. Polymer blends of polylactic acid (PLA) and polybutylene succinate-adipate

    Science.gov (United States)

    Ma, Wenguang

    A series of blends consisting of polylactic acid (PLA) and aliphatic succinate polyester (BionolleRTM #3000) had been prepared and investigated. The results of mechanical property investigations showed that using 20 wt% Bionolle#3000 can significantly increase the toughness of PLA. BionolleRTM #3000 also reduces the physical aging rate of PLA so blends remain tough longer. Conversely, the stiffness of BionolleRTM #3000 can be significantly increased by blending in PLA. DMA and DSC results show that PLA/BionolleRTM 3000 blends are not thermodynamically miscible, but are compatible blends. Studies have also been performed to determine the amount and rate of aerobic biodegradation of PLA/aliphatic succinate polyester blends in biologically active composting, enzymatic, and soil environments. The changes in molecular weight, molecular structure and thermal properties in the composting environment were also studied by GPC, NMR and DSC analyses. The research results showed BionolleRTM #3000 had a high degradation rate, while PLA had a low degradation rate. PLA/BionolleRTM #3000 blends had moderate degradation rates that increased with BionolleRTM #3000 content. The melt flow behavior of PLA/BionolleRTM #3000 blends has been studied by capillary rheometry. The relationship of the blends' viscosity with their composition, shear stress, shear rate, and temperature has been investigated. Power law index and activation energy of PLA, BionolleRTM #3000 and their blends have been calculated. The experimental and theoretical data can let us understand the processability of PLA/BionolleRTM #3000 blends. A scanning electron microscope (SEM) was used to investigate the morphological structure of the PLA/BionolleRTM #3000 blends. Micrographs of the samples made from different methods (blown film, extrudate and compression molding sheet) were taken; their differences in morphology were compared. For comparison, the micrographs of blend PLA/BionolleRTM #6000 was also studied. The

  10. Mechanical strength of various cyanate ester/epoxy insulation systems after reactor irradiation

    International Nuclear Information System (INIS)

    Prokopec, R.; Humer, K.; Maix, R.K.; Fillunger, H.; Weber, H.W.

    2006-01-01

    In order to ensure safety operation of the magnet coils, the insulation system must keep its mechanical strength over the whole magnet lifetime under the appropriate radiation environment. Recent results on cyanate ester/epoxy blends demonstrated their mechanical integrity after irradiation to the ITER design fluence level, i.e. 1 x 10 22 m -2 (E > 0.1 MeV). For economic reasons, the cyanate ester content in the blend should be kept as low as possible due to the higher price compared to traditional epoxy resins. Therefore, the optimal composition of cyanate ester and epoxy in the blend is of great importance. In this study R-glass fiber/ Kapton reinforced cyanate ester based blends using different epoxy resins and epoxy contents were investigated. Short-beam shear as well as static tensile tests were carried out at 77 K prior to and after irradiation to a fast neutron fluence of 1 and 2 x 10 22 m -2 (E > 0.1 MeV) in the TRIGA reactor (Vienna) at ambient temperature (340 K). In addition, tension-tension fatigue measurements were performed in the load and the strain controlled mode in order to simulate the pulsed operation conditions of the ITER magnets. Initial results show, that cyanate ester contents of both 40 % and 30 % lead only to a small reduction of the mechanical strength after irradiation to the ITER design fluence. (author)

  11. A bio-based ‘green’ process for catalytic adipic acid production from lignocellulosic biomass using cellulose and hemicellulose derived γ-valerolactone

    International Nuclear Information System (INIS)

    Han, Jeehoon

    2016-01-01

    Highlights: • A bio-based ‘green’ process for catalytic conversion of corn stover to adipic acid (ADA) is studied. • New separations for effective recovery of biomass derivatives are developed. • Separations are integrated with cellulose/hemicellulose-to-ADA conversions. • Proposed process can compete economically with the current petro-based process. - Abstract: A bio-based ‘green’ process is presented for the catalytic conversion of corn stover to adipic acid (ADA) based on experimental studies. ADA is used for biobased nylon 6.6 manufacturing from lignocellulosics as carbon and energy source. In this process, the cellulose and hemicellulose fractions are catalytically converted to γ-valerolactone (GVL), using cellulose and hemicellulose-derived GVL as a solvent, and subsequently upgrading to ADA. Experimental studies showed maximal carbon yields (biomass-to-GVL: 41% and GVL-to-ADA: 46%) at low concentrations (below 16 wt% solids) using large volumes of GVL solvents while requiring efficient interstage separations and product recovery. This work presents an integrated process, including catalytic conversion and separation subsystems for GVL and ADA production and recovery, and designs a heat exchanger network to satisfy the total energy requirements of the integrated process via combustion of biomass residues (lignin and humins). Finally, an economic analysis shows that 2000 metric tonnes (Mt) per day of corn stover feedstock processing results in a minimum selling price of $633 per Mt if using the best possible parameters.

  12. Gamma radiolysis and vinyl esters

    International Nuclear Information System (INIS)

    De Bruyn, H.; Balic, R.; Gilbert, R.G.

    1998-01-01

    The principle behind γ relaxation of free-radical polymerizations is that the source of initiating radicals can be switched off 'instantaneously'. In the absence of initiating radicals the only kinetic events remaining are propagation, transfer and termination. For monomers whose propagation rate coefficients have been determined, relaxation behaviour can be interpreted to determine radical-loss rate coefficients and test models of loss mechanisms. This technique has been employed successfully on styrene and MMA emulsion polymerizations. In the present study, vinyl acetate and vinyl neo-decanoate (a ten-carbon-branched homologue of vinyl acetate) were studied, with the propagation rate coefficients for both monomers being established by pulsed-laser polymerization. Both were found to exhibit rapid γ relaxation rates in emulsion polymerization. This is a surprising result because mechanisms for rapid relaxation in emulsion polymerizations require that chain transfer to monomer (which is rapid for both monomers) is followed by exit from the particle into the aqueous phase with subsequent re-entry into a radical-containing particle leading to bimolecular termination. It is not unreasonable to suppose that this may be possible for vinyl acetate which is fairly water soluble (∼0.3 M). However, vinyl neo-decanoate is virtually insoluble (∼0.00004 M) and hence desorption is extremely unlikely. The most likely explanation for the observed rapid relaxations is that some of the radicals produced by γ radiolysis are slow to initiate vinyl esters and hence act as radical traps. As vinyl esters are known to be particularly unreactive monomers. it is feasible that this experimental artifact affects them to a much greater extent than some of the monomers studied successfully with this technique in the past

  13. Performance of the mineral blended ester oil-based drilling fluid systems

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, A.R.; Kamis, A.; Foo, K.S. [University Teknologi (Malaysia)

    2001-06-01

    A study was conducted in which the properties of ester oil-based drilling fluid systems were examined using a blended mixture of ester and synthetic mineral oil. Biodegradable invert emulsion ester-based fluids are preferred over mineral oil-based drilling fluids for environmental reasons, but they tend to cause alkaline hydrolysis resulting in solidification of the drilling fluid systems. The drilling fluid examined here consisted of Malaysian palm oil ester derivatives (methyl laureate ester or isopropyl laureate ester) blended with commercially available synthetic mineral oil. This mineral oil was added to reduce the problem of alkaline hydrolysis. This mixture, however, was found to be unstable and could not solve the problem at high temperature. The isopropyl laureate and mineral oil blended system was more stable towards the hydrolysis process up to 250 degrees F. In order to enhance the performance of an invert emulsion drilling fluid system, it was recommended that brine water content of the fluid system be lowered. 3 refs., 2 figs.

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

    Science.gov (United States)

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

    2015-01-01

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

  15. Encapsulation of phytosterols and phytosterol esters in liposomes made with soy phospholipids by high pressure homogenization.

    Science.gov (United States)

    Wang, Fan C; Acevedo, Nuria; Marangoni, Alejandro G

    2017-11-15

    Phytosterols and phytosterol esters were encapsulated within large unilamellar liposomes prepared with soy phospholipids using a microfluidizer. The average particle diameter of these liposomal vesicles increased with increasing amounts of encapsulated phytosterols, especially with increasing free sterol content. The phytosterol content, liposomal particle size, and phytosterol encapsulation efficiency started to plateau when liposomes were prepared with MOPS buffer dispersions that contained 50 mg ml -1 soy phospholipid and more than 4% phytosterol blend, suggesting the saturation of phytosterol encapsulation. We proposed an encapsulation mechanism of free sterols and phytosterol esters in liposomes, where free sterols were mainly encapsulated within the lumen of these liposomes as crystals, and sterol esters and some free sterols were incorporated within the phospholipid bilayer of the liposomal membrane. The results from this work could provide the pharmaceutical and nutraceutical industries a practical method to produce loaded liposomes using inexpensive phospholipid mixtures for the delivery of bioactive ingredients.

  16. Determination of inositol phosphate ester in lake sediments

    International Nuclear Information System (INIS)

    Weimer, W.C.; Armstrong, D.E.

    1977-01-01

    A procedure for the determination of the total inositol polyphosphate content of lake sediments is presented and evaluated. This technique involves extraction with NaOH, cleanup of the extract, and isolation and identification of two groups of inositol phosphate esters by ion-exchange chromatography. Radioisotope dilution is employed to correct for losses during the extraction, cleanup and isolation steps. Recoveries of the radiotracer inositol phosphates have averaged 85% during the analysis of approximately 40 calcareous and non-calcareous sediment samples and more than 20 soil samples

  17. Tribochemical behaviors of phosphite esters and their combinations with alkyl amines

    International Nuclear Information System (INIS)

    Fu, Xisheng; Sun, Lingguo; Zhou, Xuguang; Li, Jianchang; Fan, Bingji; Ren, Tianhui

    2015-01-01

    Highlights: • Investigating the differences of tribological performance between phosphite ester and their combinations with alkyl amines. • The combination of SEM and EDS was used to investigate the worn surface morphology and detect the element distributions and content on the steel surface. • The chemical compositions of the thermal films and tribofilms were characterized by TEY P L-edge and FY P K-edge XANES spectroscopy. • A phosphate and polyphosphate tribofilm was formed after rubbing times of even 10 s, and being formed completely after rubbing times of 10 min. • Phosphite ester forms short-chain polyphosphates, and ammonium phosphite produces medium-chain polyphosphates in the tribfilm. - Abstract: The tribochemical behaviors of dioctylphosphite ester and ditetradecylphosphite ester together with their corresponding combinations with alkyl amines were studied. The results of tribological evaluations showed that the phosphite ester with long alkyl chain exhibited better antiwear performance but worse extreme pressure property than that of the phosphite ester with short alkyl chain. The combinations showed better antiwear performance but worse extreme pressure property than their corresponding phosphite esters. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to investigate the worn surface morphology and the content as well as the distribution of active elements. It can be found that the prorupt edges of worn surface are enriched with phosphoric-oxygenic compounds and less phosphoric-oxygenic compounds were detected in the valley. X-ray absorption near-edge structure (XANES) spectroscopy was employed to explore the chemical nature of the worn surface. The results show that a tribofilm composed of phosphates and polyphosphates is formed on the worn surface. Furthermore, the tribofilm is generated even in a rubbing of 10 s and is formed completely after 10 min rubbing.

  18. Rapid screening of fatty acid alkyl esters in olive oils by time domain reflectometry.

    Science.gov (United States)

    Berardinelli, Annachiara; Ragni, Luigi; Bendini, Alessandra; Valli, Enrico; Conte, Lanfranco; Guarnieri, Adriano; Toschi, Tullia Gallina

    2013-11-20

    The main aim of the present research is to assess the possibility of quickly screening fatty acid alkyl esters (FAAE) in olive oils using time domain reflectometry (TDR) and partial least-squares (PLS) multivariate statistical analysis. Eighteen virgin olive oil samples with fatty acid alkyl ester contents and fatty acid ethyl ester/methyl ester ratios (FAEE/FAME) ranging from 3 to 100 mg kg(-1) and from 0.3 to 2.6, respectively, were submitted to tests with time domain resolution of 1 ps. The results obtained in test set validation demonstrated that this new and fast analytical approach is able to predict FAME, FAEE, and FAME + FAEE contents with R(2) values of 0.905, 0.923, and 0.927, respectively. Further measurements on mixtures between olive oil and FAAE standards confirmed that the prediction is based on a direct influence of fatty acid alkyl esters on the TDR signal. The suggested technique appeared potentially suitable for monitoring one of the most important quality attribute of the olive oil in the extraction process.

  19. 21 CFR 172.854 - Polyglycerol esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyglycerol esters of fatty acids. 172.854 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.854 Polyglycerol esters of fatty acids. Polyglycerol esters of fatty acids, up to and including the decaglycerol esters, may be safely used in food in...

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

    Science.gov (United States)

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

    2015-10-12

    The atom-efficient and environmentally benign catalytic hydrogenation of carboxylic acid esters to alcohols has been accomplished in recent years mainly with precious-metal-based catalysts, with few exceptions. Presented here is the first cobalt-catalyzed hydrogenation of esters to the corresponding alcohols. Unexpectedly, the evidence indicates the unprecedented involvement of ester enolate intermediates. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Synthesis of a new energetic nitrate ester

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, David E [Los Alamos National Laboratory

    2008-01-01

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

  2. Allied, MGC link on cyanate esters

    International Nuclear Information System (INIS)

    Wood, A.

    1993-01-01

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

  3. Light induced degradation of phorbol esters.

    Science.gov (United States)

    Yunping, Bu; Ha, Bui Thi Ngoc; Eunice, Yeo; Chueng, Lo Loong; Yan, Hong

    2012-10-01

    Jatropha curcas (Jatropha) is a tropical shrub that is gaining popularity as a biofuel feedstock plant. Phorbol esters (PEs) are tetracyclic tiglian diterpenoids that are present in Jatropha seeds and other parts of plant. Epidermal cell irritating and cancer promoting PEs not only reduce commercial values of Jatropha seed cake but also cause some safety and environment concerns on PE leaching to soil. A simple bioassay of PE toxicity was conducted by incubating 48 h old brine shrimp (Artemia salina) nauplii with Jatropha oil for 24 h. 1-4% of Jatropha oil (corresponding to PE concentration of 25-100 mg L(-1)) had mortality rate of 5-95%, with LC50 estimated to be 2.7% of oil or 67 mg L(-1) of PE. Jatropha oil was incubated with clay or black soil (autoclaved or non-autoclaved) in the darkness or under sunlight for different periods of time before oil was re-extracted and tested for PE content by HPLC and for remaining toxicity with the brine shrimp bioassay. Under sunlight, PE decreased to non-detectable level within six days. Toxicity reduced to less than 5% mortality rate that is comparable to rapeseed oil control within the same period. In contrast, PE level and toxicity remained little changed when Jatropha oil was incubated in the darkness. Such PE degradation/detoxification was also found independent of the presence of soil or soil microorganisms. We conclude that sunlight directly degrades and detoxifies PEs and this finding should alleviate the concern on long term environmental impact of PE leaching. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Near Infrared Spectroscopic Identification of Alkyl Aromatic Esters and Phenyl Ketones

    Science.gov (United States)

    Nelyubov, D. V.; Vazhenin, D. A.; Kudriavtsev, A. A.; Buzolina, A. Yu.

    2018-03-01

    Bands characterizing the content of carbon atoms in alkyl (7177-7205 cm-1) and phenyl structural fragments (9175-9192 cm-1) in organic molecules were revealed by studying the near infrared spectra of such compounds. The optical density at the maxima of these absorption bands was shown to depend strongly on the fraction of carbon atoms in the corresponding fragments. The developed models proved to be adequate for determining the fraction of carbon atoms in alkyl aromatic esters and phenyl ketones. The feasibility of modeling the molecular structure of alkyl aromatic esters using regression models was demonstrated for the product of the condensation of oleic acid and benzyl alcohol.

  5. Rapid and simple micromethod for the simultaneous determination of 3-MCPD and 3-MCPD esters in different foodstuffs.

    Science.gov (United States)

    Küsters, Markus; Bimber, Ute; Ossenbrüggen, Alexandra; Reeser, Sebastian; Gallitzendörfer, Rainer; Gerhartz, Michael

    2010-06-09

    This paper describes for the first time a micromethod for the simultaneous determination of 3-monochloropropane-1,2-diol (3-MCPD) and fatty acid esters of 3-MCPD (3-MCPD esters) in different foodstuffs. 3-MCPD and 3-MCPD esters were isolated from food products using a single extraction step separating hydrophilic and lipophilic compounds. An aliquot of the aqueous layer was analyzed for the content of 3-MCPD while a part of the organic layer was analyzed for 3-MCPD esters after cleavage with sodium methoxide. After a simple derivatization procedure with phenylboronic acid (PBA), the determination was achieved by isotope dilution GC-MS using isotope-labeled 3-MCPD and 3-MCPD ester as internal standards. The method was validated for various foodstuffs like bakery products, meat and fish products, and soups as well as seasonings with LOD of 1-2 microg/kg (3-MCPD) and 6 microg/kg (3-MCPD esters), respectively. Recoveries ranged within 95 +/- 9% and 96 +/- 10% at spiking levels of 15 and 25 microg/kg in all matrices for 3-MCPD and 84 +/- 9% and 85 +/- 7% at spiking levels of 0.05 mg/kg and 2 mg/kg for 3-MCPD esters. The method avoids tedious and laborious sample preparation and was successfully applied to the rapid screening of samples conforming to the EU performance criteria for methods of analysis for 3-MCPD.

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

    Science.gov (United States)

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

  7. Effect of sugar fatty acid esters on rumen fermentation in vitro.

    Science.gov (United States)

    Wakita, M; Hoshino, S

    1987-11-01

    1. The effect of sugar fatty acid esters (SFEs; currently used as food additives for human consumption) on rumen volatile fatty acids (VFA) and gas production was studied with sheep rumen contents in vitro. 2. Some SFEs having monoester contents of more than 70% increased the molar proportion of propionate in conjunction with reduction in the acetate:propionate ratio when the individual SFE was added to rumen contents in a final concentration of 4 g/l. Laurate sugar ester was the most potent propionate enhancer and rumen gas depressor, the effective dose being as low as 1 g/l in a final concentration. Fatty acid esters other than SFEs had little, if any, effect on rumen VFA production and their molar proportions. 3. Approximately 50% of laurate sugar ester was hydrolysed by in vitro incubation with rumen fluid for 2 h. The addition of fatty acids and sucrose was also effective in the alterations of rumen VFA and gas production. However, the effect of SFEs on in vitro rumen fermentation was significantly greater than that of their constituent fatty acids or sucrose, or both. Accordingly, the effect appeared to be ascribed to the complex action of SFE itself and to its constituents, free fatty acids and sucrose. 4. SFEs, at the level of 4 g/l, reduced substantially the froth formation (ingesta volume increase) and seemed to be effective for the prevention of bloat.

  8. Use of calcium oxide in palm oil methyl ester production

    Directory of Open Access Journals (Sweden)

    Kulchanat Prasertsit

    2014-04-01

    Full Text Available Introducing an untreated calcium oxide (CaO as a solid heterogeneous catalyst for biodiesel production from palm oil by transesterification was studied in this work. The four studied parameters were methanol to oil molar ratio, CaO catalyst concentration, reaction time, and water content. The results for palm oil show that when the water content is higher than 3%wt and the amount of CaO greater than 7%wt soap formation from saponification occurs. A higher methanol to oil molar ratio requires a higher amount of CaO catalyst to provide the higher product purity. The appropriate methanol to CaO catalyst ratio is about 1.56. Commercial grade CaO gives almost the same results as AR grade CaO. In addition, reusing commercial grade CaO for about 5 to 10 repetitions without catalyst regeneration drops the percentage of methyl ester purity approximately 5 to 10%, respectively.

  9. Analysis of the ecological parameters of the diesel engine powered with biodiesel fuel containing methyl esters from Camelina sativa oil

    Directory of Open Access Journals (Sweden)

    S. Lebedevas

    2010-03-01

    Full Text Available The article explores the possibilities of using fatty acid methyl esters derived from the oil of a new species of oily plant Camelina sativa not demanding on soil. The performed research on the physical and chemical properties of pure methyl esters from Camelina sativa show that biofuels do not meet requirements for the biodiesel fuel standard (LST EN 14214:2009 of a high iodine value and high content of linoleic acid methyl ester, so they must be mixed with methyl esters produced from pork lard the content of which in the mixture must be not less than 32%. This article presents the results of tests on combustion emission obtained when three-cylinder diesel engine VALMET 320 DMG was fuelled with a mixture containing 30% of this new kind of fuel with fossil diesel fuel comparing with emissions obtained when the engine was fuelled with a fuel mixture containing 30% of conventional biodiesel fuel (rapeseed oil methyl esters with fossil diesel fuel. The obtained results show that using both types of fuel, no significant differences in CO and NOx concentrations were observed throughout the tested load range. When operating on fuels containing methyl esters from Camelina sativa, HC emissions decreased by 10 to 12% and the smokeness of exhaust gas by 12 to 25%.

  10. Fucoidan cytotoxicity against human breast cancer T47D cell line increases with higher level of sulfate ester group

    Science.gov (United States)

    Saepudin, Endang; Alfita Qosthalani, Fildzah; Sinurat, Ellya

    2018-01-01

    The anticancer activity of different sulfate ester group content in different molecular weight was examined. The anticancer activity was achieved in vitro on human breast cancer T47D cell line. Fucoidan with lower molecular weight (5.79 kDa) tends to have lower sulfate ester group content (8.69%) and resulted in higher IC50 value (184.22 μg/mL). While fucoidan with higher molecular weight (785.12 kDa) tends to have higher sulfate level (18.63%) and achieved lower IC50 value (75.69 μg/mL). The result showed that in order to maintain fucoidan cytotoxic activity against human breast cancer T47D cell line, the sulfate content should be remain high. Keywords: fucoidan, sulfate ester group, human breast cancer

  11. Degradation of Jatropha curcas phorbol esters derived from Jatropha oil cake and their tumor-promoting activity.

    Science.gov (United States)

    Nakao, Motoyuki; Hasegawa, Go; Yasuhara, Tadashi; Ishihara, Yoko

    2015-04-01

    Large amount of oil cake is generated during biodiesel production from Jatropha seeds. Although Jatropha oil cake is rich in plant nutrients, presence of toxic phorbol esters restricts the usage of oil cake as a fertilizer. The objective of this study is to evaluate the components and tumor promoting activity of phorbol esters in Jatropha oil cake-supplemented soil and plants grown in the treated soil. Contents and their biological activity of Jatropha phorbol esters in soil and plants were sequentially analyzed by high-performance liquid chromatography (HPLC) and in vitro cell transformation assay, respectively. Disappearance of Jatropha phorbol-ester-specific peaks were followed with HPLC during incubation of Jatropha oil cake with soil for five weeks. Along with the degradation of Jatropha phorbol ester in soil, tumor-promoting activity in the sample was also attenuated and ultimately disappeared. Jatropha phorbol esters and tumor promoting activity were not detected from mustard spinach grown in the Jatropha oil cake-supplemented soil. In addition, the esterase KM109 degrades DHPB (see definition below; Jatropha phorbol ester) and reduced its tumor-promoting activity. From these data, we conclude: (1) components and tumor promoting activity of Jatropha phorbol esters in the oil cake disappeared completely by incubation with soil for five-week, (2) Jatropha phorbol esters did not transfer into plants grown in the Jatropha oil cake-supplemented soil, and (3) DHPB can be degraded by esterase from soil bacterium. These observations are useful for utilization of Jatropha oil cake as a fertilizer. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Autoclave-hardening slag-alkali binder with high water content

    International Nuclear Information System (INIS)

    Korenevskij, V.V.; Kozyrin, N.A.; Melikhova, N.I.; Narkevich, N.K.; Ryabov, G.G.

    1987-01-01

    The results of investigations into properties of slag-alkali binder, that may be used for concretes of reactor radiation and thermal shieldings, are presented. These concretes have increased chemical stability and mechanical strength, high content of chemically bound water (approximately 14%), that is not lost under heating up to 550 deg C. Dumping and granulated slags of blast-furnace process, sodium-bicarbonate-alkali fusion cake formed at burning of adipic acid residues, technical sodium hydroxide and sodium liquid glass are used as raw material for slag-alkali binder

  13. The European source term code ESTER - basic ideas and tools for coupling of ATHLET and ESTER

    International Nuclear Information System (INIS)

    Schmidt, F.; Schuch, A.; Hinkelmann, M.

    1993-04-01

    The French software house CISI and IKE of the University of Stuttgart have developed during 1990 and 1991 in the frame of the Shared Cost Action Reactor Safety the informatic structure of the European Source TERm Evaluation System (ESTER). Due to this work tools became available which allow to unify on an European basis both code development and code application in the area of severe core accident research. The behaviour of reactor cores is determined by thermal hydraulic conditions. Therefore for the development of ESTER it was important to investigate how to integrate thermal hydraulic code systems with ESTER applications. This report describes the basic ideas of ESTER and improvements of ESTER tools in view of a possible coupling of the thermal hydraulic code system ATHLET and ESTER. Due to the work performed during this project the ESTER tools became the most modern informatic tools presently available in the area of severe accident research. A sample application is given which demonstrates the use of the new tools. (orig.) [de

  14. Palladium-catalysed arylation of acetoacetate esters to yield 2-arylacetic acid esters

    CSIR Research Space (South Africa)

    Zeevaart, JG

    2004-05-24

    Full Text Available , was developed simultaneously by Hart- wig and Buchwald.5 Typically the tert-butyl ester of propionic acid is treated with an aryl halide (bromide or chloride) in the presence of a strong base, palladium and a bulky phosphine ligand or a bulky imidazolinium CO2t... novel palladium- catalysed conditions for the arylation of acetoacetate esters resulting in the formation of 2-arylacetic acid esters. When we attempted the arylation of tert-butyl aceto- acetate 1a with bromobenzene 2a using mild reaction conditions (K3...

  15. Segmented poly(ether ester)s and poly(ether ester amide)s for use in tissue engineering

    OpenAIRE

    Deschamps, A.A.

    2002-01-01

    The objective of the studies described in this thesis is to investigate the applicability of these slowly degradable thermoplastic elastomers as scaffolds for tissue engineering, with emphasis on their phase separation and degradation properties. A second thermoplastic elastomer in which the terephthalic moieties have been replaced by ester-amide segments, is also investigated for use in scaffolding.

  16. Metabolism of cholesteryl esters of rat very low density lipoproteins.

    Science.gov (United States)

    Faergeman, O; Havel, R J

    1975-06-01

    Rat very low density lipoproteins (d smaller than 1.006), biologically labeled in esterified and free cholesterol, were obtained form serum 6 h after intravenous injection of particulate (3-H) cholesterol. When injected into recipient animals, the esterified cholesterol was cleared form plasma with a half-life of 5 min. After 15 min, 71% of the injected esterified (3-H) cholesterol had been taken up by the liver, where it was rapidly hydrolyzed. After 60 min only 3.3% of the amount injected had been transferred, via lipoproteins of intermediate density, to the low density lipoproteins of plasma (d 1.019-1.063). Both uptake in the liver and transfer to low density lipoproteins occurred without change of distribution of 3-H in the various cholesteryl esters. 3-H appearing in esterified cholesterol of high density lipoproteins (d greater than 1.063) was derived from esterification, presumably by lecithin: cholesterol acyltransferase, of simultaneously injected free (3-H) cholesterol. Content of free (3-H) cholesterol in the very low density lipoproteins used for injection could be reduced substantially by incubation with erythrocytes. This procedure, however, increased the rate of clearance of the lipoproteins after injection into recipient rats. These studies show that hepatic removal is the major catabolic pathway for cholesteryl esters of rat very low density lipoproteins and that transfer to low density lipoproteins occurs to only a minor extent.

  17. Using the Maturity Method in Predicting the Compressive Strength of Vinyl Ester Polymer Concrete at an Early Age

    Directory of Open Access Journals (Sweden)

    Nan Ji Jin

    2017-01-01

    Full Text Available The compressive strength of vinyl ester polymer concrete is predicted using the maturity method. The compressive strength rapidly increased until the curing age of 24 hrs and thereafter slowly increased until the curing age of 72 hrs. As the MMA content increased, the compressive strength decreased. Furthermore, as the curing temperature decreased, compressive strength decreased. For vinyl ester polymer concrete, datum temperature, ranging from −22.5 to −24.6°C, decreased as the MMA content increased. The maturity index equation for cement concrete cannot be applied to polymer concrete and the maturity of vinyl ester polymer concrete can only be estimated through control of the time interval Δt. Thus, this study introduced a suitable scaled-down factor (n for the determination of polymer concrete’s maturity, and a factor of 0.3 was the most suitable. Also, the DR-HILL compressive strength prediction model was determined as applicable to vinyl ester polymer concrete among the dose-response models. For the parameters of the prediction model, applying the parameters by combining all data obtained from the three different amounts of MMA content was deemed acceptable. The study results could be useful for the quality control of vinyl ester polymer concrete and nondestructive prediction of early age strength.

  18. Influence of the adipate and dissolved oxygen concentrations on the beta-lactam production during continuous cultivations of a Penicillium chrysogenum strain expressing the expandase gene from Streptomyces clavuligerus

    DEFF Research Database (Denmark)

    Robin, Jarno Jacky Christian; Bonneau, S.; Schipper, D.

    2003-01-01

    The influence of adipate concentration and dissolved oxygen on production of adipoyl-7-aminodeacetoxycephalosporanic acid (ad-7-ADCA) by a recombinant strain of Penicillium chrysogenum expressing the expandase gene from Streptomyces clavuligerus was studied in glucose-limited continuous cultures....... from 15 to 7%AS, r(p) (total) increased to 25 mumol g DW-1 h(-1), mainly due to a two-fold increase in the adipoyl-6-aminopenicillanic acid (ad-6-APA) specific productivity....

  19. Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + ethyl pentanoate + ethyl ethanoate

    International Nuclear Information System (INIS)

    Pérez, Noelia; Fernández, Luís; Ortega, Juan; Toledo, Francisco J.; Wisniak, Jaime

    2012-01-01

    Highlights: ► Excess enthalpies and volumes were measured for ester–ester–alkane. ► Mixing behaviour for ester–ester, ester–alkane and ester–ester–alkane are analyzed. ► Correlations with a new polynomial model reproduce well the mixing properties. ► UNIFAC predictions for h E result acceptable excluding the ester–ester mixtures. - Abstract: Excess thermodynamic properties V m E and H m E , have been measured for the ternary mixture dodecane + ethyl pentanoate + ethyl ethanoate and for the corresponding binaries dodecane + ethyl pentanoate, dodecane + ethyl ethanoate, ethyl pentanoate + ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H m E yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.

  20. Naturally Occurring Cinnamic Acid Sugar Ester Derivatives

    Directory of Open Access Journals (Sweden)

    Yuxin Tian

    2016-10-01

    Full Text Available Cinnamic acid sugar ester derivatives (CASEDs are a class of natural product with one or several phenylacrylic moieties linked with the non-anomeric carbon of a glycosyl skeleton part through ester bonds. Their notable anti-depressant and brains protective activities have made them a topic of great interest over the past several decades. In particular the compound 3′,6-disinapoylsucrose, the index component of Yuanzhi (a well-known Traditional Chinese Medicine or TCM, presents antidepressant effects at a molecular level, and has become a hotspot of research on new lead drug compounds. Several other similar cinnamic acid sugar ester derivatives are reported in traditional medicine as compounds to calm the nerves and display anti-depression and neuroprotective activity. Interestingly, more than one third of CASEDs are distributed in the family Polygalaceae. This overview discusses the isolation of cinnamic acid sugar ester derivatives from plants, together with a systematic discussion of their distribution, chemical structures and properties and pharmacological activities, with the hope of providing references for natural product researchers and draw attention to these interesting compounds.

  1. Supra-molecular architecture in a co-crystal of the N(7)-H tautomeric form of N (6)-benzoyl-adenine with adipic acid (1/0.5).

    Science.gov (United States)

    Swinton Darious, Robert; Thomas Muthiah, Packianathan; Perdih, Franc

    2016-06-01

    The asymmetric unit of the title co-crystal, C12H9N5O·0.5C6H10O4, consists of one mol-ecule of N (6)-benzoyl-adenine (BA) and one half-mol-ecule of adipic acid (AA), the other half being generated by inversion symmetry. The dihedral angle between the adenine and phenyl ring planes is 26.71 (7)°. The N (6)-benzoyl-adenine mol-ecule crystallizes in the N(7)-H tautomeric form with three non-protonated N atoms. This tautomeric form is stabilized by intra-molecular N-H⋯O hydrogen bonding between the carbonyl (C=O) group and the N(7)-H hydrogen atom on the Hoogsteen face of the purine ring, forming an S(7) ring motif. The two carboxyl groups of adipic acid inter-act with the Watson-Crick face of the BA mol-ecules through O-H⋯N and N-H⋯O hydrogen bonds, generating an R 2 (2)(8) ring motif. The latter units are linked by N-H⋯N hydrogen bonds, forming layers parallel to (10-5). A weak C-H⋯O hydrogen bond is also present, linking adipic acid mol-ecules in neighbouring layers, enclosing R (2) 2(10) ring motifs and forming a three-dimensional structure. C=O⋯π and C-H⋯π inter-actions are also present in the structure.

  2. Ester Tuiksoo - Eesti esimene naissoost põllumajandusminister / Ester Tuiksoo ; interv. Toomas Verrev

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Ametist lahkuv põllumajandusminister Ester Tuiksoo räägib saadud juhtimiskogemusest, Euroopa Liidu ühise põllumajanduspoliitika juurutamisest, rahvuskala valimisest, Rahvaliidu käekäigust parlamendivalimistel

  3. QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis

    Science.gov (United States)

    Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

    1985-01-01

    Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of catonic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR'P(O)X, where R and R' are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrogen hydrolysis rate constant.

  4. Technetium and rhenium tracers with metabolizable ester functions

    International Nuclear Information System (INIS)

    Syhre, R.; Seifert, S.; Schneider, F.; Pietzsch, H.J.; Spies, H.; Johannsen, B.

    1993-01-01

    Re-DMSA (dimercaptosuccinic acid) ester complexes were prepored by ligand exchange reactions. To determine whether the ester band in Re-DMSA ester complexes is susceptible to cleavage by esterases, incubation experiments with tissue homogenates and plasma were carried out. (BBR)

  5. 21 CFR 172.848 - Lactylic esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lactylic esters of fatty acids. 172.848 Section 172... CONSUMPTION Multipurpose Additives § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids... prepared from lactic acid and fatty acids meeting the requirements of § 172.860(b) and/or oleic acid...

  6. Celorbicol, isocelorbicol, and their esters: new sesquiterpenoids from Celastrus orbiculatus

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.R. Jr. (Dept. of Agriculture, Peoria, IL); Miller, R.W.; Weisleder, D.; Rohwedder, W.K.; Eickman, N.; Clardy, J.

    1976-10-01

    Esters of two new sesquiterpenoid polyalcohols - celorbicol and isocelorbicol - have been isolated from Celastrus orbiculatus. Structures of the parent alcohols have been established by x-ray crystallography, and those of the derived esters have been assigned by NMR spectroscopy. These compounds are structurally related to other polyesters and ester alkaloids from the Celastraceae, all of which are based on the dihydroagarofuran ring system.

  7. Synthesis of 11C labelled methyl esters: transesterification of enol esters versus BF3 catalysed esterification-a comparative study

    International Nuclear Information System (INIS)

    Ackermann, Uwe; Blanc, Paul; Falzon, Cheryl L.; Issa, William; White, Jonathan; Tochon-Danguy, Henri J.; Sachinidis, John I.; Scott, Andrew M.

    2006-01-01

    C-11 labelled methyl esters have been synthesized via the transesterification of enol esters in the presence of C-11 methanol and 1,3 dichlorodibutylstannoxane as catalyst. This method leaves functional groups intact and allows access to a wider variety of C-11 labelled methyl esters compared to the BF 3 catalysed ester formation, which uses carboxylic acids and C-11 methanol as starting materials

  8. Rearrangement of beta,gamma-unsaturated esters with thallium trinitrate: synthesis of indans bearing a beta-keto ester moiety

    Directory of Open Access Journals (Sweden)

    Silva Jr. Luiz F.

    2006-01-01

    Full Text Available The rearrangement of beta,gamma-unsaturated esters, such as 2-(3,4-dihydronaphthalen-1-yl-propionic acid ethyl ester, with thallium trinitrate (TTN in acetic acid leads to 3-indan-1-yl-2-methyl-3-oxo-propionic acid ethyl ester in good yield, through a ring contraction reaction. The new indans thus obtained feature a beta-keto ester moiety, which would be useful for further functionalization.

  9. Production of novel "functional oil" rich in diglycerides and phytosterol esters with "one-pot" enzymatic transesterification.

    Science.gov (United States)

    Zheng, Ming-Ming; Huang, Qing; Huang, Feng-Hong; Guo, Ping-Mei; Xiang, Xia; Deng, Qian-Chun; Li, Wen-Lin; Wan, Chu-Yun; Zheng, Chang

    2014-06-04

    Diglycerides and phytosterol esters are two important functional lipids. Phytosterol esters mixed with dietary diglyceride could not only influence body weight but also prevent or reverse insulin resistance and hyperlipidemia. In this study, a kind of novel "functional oil" rich in both diglycerides and phytosterol esters was prepared with "one-pot" enzymatic transesterification. First, lipase AYS (Candida rugosa) was immobilized on the porous cross-linked polystyrene resin beads (NKA) via hydrophobic interaction. The resulting immobilized AYS showed much better transesterification activity and thermal stability to freeways. On the basis of the excellent biocatalyst prepared, a method for high-efficiency enzymatic esterification of phytosterols with different triglycerides to produce corresponding functional oils rich in both diglycerides and phytosterol esters was developed. Four functional oils rich in both diglycerides and phytosterol esters with conversions >92.1% and controllable fatty acid composition were obtained under the optimized conditions: 80 mmol/L phytosterols, 160 mmol/L triglycerides, and 25 mg/mL AYS@NKA at 180 rpm and 50 °C for 12 h in hexane. The prepared functional oil possessed low acid value (≤1.0 mgKOH/g), peroxide value (≤2.1 mmol/kg), and conjugated diene value (≤1.96 mmol/kg) and high diglyceride and phytosterol ester contents (≥10.4 and ≥20.2%, respectively). All of the characteristics favored the wide application of the functional oil in different fields of functional food.

  10. Acceleration effect of ionic liquids on polycyclotrimerization of dicyanate esters

    Directory of Open Access Journals (Sweden)

    A. Fainleib

    2016-09-01

    Full Text Available The polycyclotrimerization reaction of dicyanate ester of bisphenol E (DCBE in the presence of varying amounts (from 0.5 to 5 wt% of 1-octyl-3-methylimidazolium tetrafluoroborate ([OMIm][BF4] ionic liquid has been investigated using differential scanning calorimetry (DSC and Fourier transform infrared spectroscopy (FTIR techniques, after a curing stage at 150 °C for 6 h. It is noteworthy that an amount of [OMIm][BF4] as low as 0.5 wt% accelerates dramatically the thermal curing process leading to the formation of a polycyanurate network. The conversion of DCBE increased with increasing [OMIm][BF4] content in the temperature range studied. A reaction mechanism associated with the ionic liquid-catalyzed DCBE polycyclotrimerization is newly proposed via the involvement of a [CN]δ+–[OMIm]δ– complex as a key intermediate.

  11. Nanoporous Polymer Films of Cyanate Ester Resins Designed by Using Ionic Liquids as Porogens.

    Science.gov (United States)

    Fainleib, Alexander; Vashchuk, Alina; Starostenko, Olga; Grigoryeva, Olga; Rogalsky, Sergiy; Nguyen, Thi-Thanh-Tam; Grande, Daniel

    2017-12-01

    Novel nanoporous film materials of thermostable cyanate ester resins (CERs) were generated by polycyclotrimerization of dicyanate ester of bisphenol E in the presence of varying amounts (from 20 to 40 wt%) of an ionic liquid (IL), i.e., 1-heptylpyridinium tetrafluoroborate, followed by its quantitative extraction after complete CER network formation. The completion of CER formation and IL extraction was assessed using gel fraction content determination, FTIR, 1 H NMR, and energy-dispersive X-ray spectroscopy (EDX). SEM and DSC-based thermoporometry analyses demonstrated the formation of nanoporous structures after IL removal from CER networks, thus showing the effective role of IL as a porogen. Pore sizes varied from ~20 to ~180 nm with an average pore diameter of around 45-60 nm depending on the initial IL content. The thermal stability of nanoporous CER-based films was investigated by thermogravimetric analysis.

  12. Controlling the biodegradability of poly(butylene succinate-co-butylene adipate) (PBSA) by solvents used in the dried-gel process

    Science.gov (United States)

    Yamazaki, Hana; Kamitabira, Saya; Maeda, Tomoki; Hotta, Atsushi

    Considering an environmentally friendly material, poly(butylene succinate-co-butylene adipate)(PBSA) is one of the attractive biodegradable plastics that can be eventually degraded into H2O and CO2 by neighboring water molecules and microorganisms after the disposal. In order to expand the application of PBSA, the precise control of the biodegradability of PBSA is necessary. In this study, the dried-gel process was introduced to control the biodegradability of PBSA. The dried PBSA gels were prepared by using three different solvents (toluene, cyclohexanone, and o-dichlorobenzene). The scanning electron microscopy (SEM) micrographs revealed that the PBSA prepared by toluene had smaller spherocrystals than the other PBSA dried-gels prepared by cyclohexanone or o-dichlorobenzene. The biodegradability testing by immersing the three types of PBSA in NaOH aq. showed that the percentage of the weight loss of the PBSA produced by toluene was the highest. The results indicated that the microstructures of PBSA could be controlled by changing solvents during the gel preparations, and that the biodegradability of PBSA could therefore be efficiently modified by changing solvents. This work was supported by a Grant-in-Aid for Scientific Research (A) (No. 15H02298 to A.H.) and a Grant-in-Aid for Research Activity Start-up (No.15H06586 to T.M.) from JSPS: KAKENHI\\x9D.

  13. Evolution of insoluble eutectic Si particles in anodic oxidation films during adipic-sulfuric acid anodizing processes of ZL114A aluminum alloys

    Science.gov (United States)

    Hua, Lei; Liu, Jian-hua; Li, Song-mei; Yu, Mei; Wang, Lei; Cui, Yong-xin

    2015-03-01

    The effects of insoluble eutectic Si particles on the growth of anodic oxide films on ZL114A aluminum alloy substrates were investigated by optical microscopy (OM) and scanning electron microscopy (SEM). The anodic oxidation was performed at 25°C and a constant voltage of 15 V in a solution containing 50 g/L sulfuric acid and 10 g/L adipic acid. The thickness of the formed anodic oxidation film was approximately 7.13 μm. The interpore distance and the diameters of the major pores in the porous layer of the film were within the approximate ranges of 10-20 nm and 5-10 nm, respectively. Insoluble eutectic Si particles strongly influenced the morphology of the anodic oxidation films. The anodic oxidation films exhibited minimal defects and a uniform thickness on the ZL114A substrates; in contrast, when the front of the oxide oxidation films encountered eutectic Si particles, defects such as pits and non-uniform thickness were observed, and pits were observed in the films.

  14. Effect of Chain-Extenders on the Properties and Hydrolytic Degradation Behavior of the Poly(lactide/ Poly(butylene adipate-co-terephthalate Blends

    Directory of Open Access Journals (Sweden)

    Mingqing Chen

    2013-10-01

    Full Text Available Biodegradable poly(lactide/poly(butylene adipate-co-terephthalate (PLA/PBAT blends were prepared by reactive blending in the presence of chain-extenders. Two chain-extenders with multi-epoxy groups were studied. The effect of chain-extenders on the morphology, mechanical properties, thermal behavior, and hydrolytic degradation of the blends was investigated. The compatibility between the PLA and PBAT was significantly improved by in situ formation of PLA-co-PBAT copolymers in the presence of the chain-extenders, results in an enhanced ductility of the blends, e.g., the elongation at break was increased to 500% without any decrease in the tensile strength. The differential scanning calorimeter (DSC results reveal that cold crystallization of PLA was enhanced due to heterogeneous nucleation effect of the in situ compatibilized PBAT domains. As known before, PLA is sensitive to hydrolysis and in the presence of PBAT and the chain-extenders, the hydrolytic degradation of the blend was evident. A three-stage hydrolysis mechanism for the system is proposed based on a study of weight loss and molecular weight reduction of the samples and the pH variation of the degradation medium.

  15. Active biodegradable films produced with blends of rice flour and poly(butylene adipate co-terephthalate): effect of potassium sorbate on film characteristics.

    Science.gov (United States)

    Sousa, G M; Soares Júnior, M S; Yamashita, F

    2013-08-01

    The objective of work was to produce and characterize biodegradable films from rice flour, poly(butylene adipate co-terephthalate) (PBAT), glycerol and potassium sorbate, for application as active packaging for fresh lasagna pasta. The films were evaluated with respect to their optical, water vapor barrier, mechanical and microstructural properties. The mechanical properties and microstructure were evaluated after use as packaging material for fresh pasta for 45 days at 7°C. The blends of rice flour, PBAT, glycerol and potassium sorbate showed good processability and allowed for the pilot scale production of films by blow extrusion process. The addition of 1 to 5% potassium sorbate as plasticizer agent of films in place of glycerol did not alter the film mechanical properties and a sorbate concentration greater or equal than 3% reduced the opacity, although increasing the water vapor permeability. The films could be used as active packaging for fresh food pasta, since they remained integral and easy to handle after application. The rice flour was shown to be an excellent material for the formulation of biodegradable films, since it is a low-cost raw material from a renewable source. The addition of potassium sorbate did not affect the extrusion process, and could be used in the production of packaging for use with foods. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Investigation on Polylactide (PLA)/Poly(butylene adipate-co-terephthalate) (PBAT)/Bark Flour of Plane Tree (PF) Eco-Composites

    Science.gov (United States)

    Dou, Qiang; Cai, Jun

    2016-01-01

    Polylactide (PLA)/poly(butylene adipate-co-terephthalate) (PBAT)/bark flour of plane tree (PF) eco-composites were prepared via melt blending. The morphologies, mechanical properties, crystal structures and melting and crystallization behaviors of the eco-composites were investigated by means of scanning electron microscopy (SEM), mechanical tests, polarized light microscopy (PLM), wide angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC), respectively. It is shown that the interfacial adhesion between PLA matrix and PF is weak and the mechanical properties of PLA/PF eco-composites are poor. The titanate treatment improves the adhesion between the matrix and the filler and enhances the stiffness of the eco-composites. The toughness is improved by PBAT and ductile fractured surfaces can be found. The spherulitic size of PLA is decreased by the addition of PF. The α crystalline form of PLA remains in the composites. Compared with PF, T-PF (PF treated by a titanate coupling agent) and PBAT have negative effects on the crystallization of PLA. PMID:28773515

  17. Synthesis of Estolide 2-ethylhexyl Ester from Ricinus communis

    International Nuclear Information System (INIS)

    Nazrizawati Ahmad Tajuddin; Nor Habibah Rosli

    2013-01-01

    Estolide 2-ethylhexyl ester synthesized through condensation reaction between ricinoleic acid from castor oil (Ricinus communis) and lauric acid, and then capped with 2-ethylhexyl alcohol. The reaction was continuously conducted under vacuum for 24 hours. Product of 2-ethylhexyl ester was characterized by using Fourier Transform Infrared (FTIR) to determine functional group and Nuclear Magnetic Resonans (NMR) for structure's determination. The presence of ester group at 1738.23 cm -1 wavenumber indicates that the formation of estolide ester has occurred. The vibration peak of C-O at 1174.60 cm -1 and 1117.10 cm -1 support the formation of ester. The presence of CH 2 bending indicated the long-chain compound. The ester methine signal at 3.8669 ppm indicated the estolide linkage in the 1 H-NMR spectrum while the 13 C-NMR showed two carbonyl signals at 173.41 ppm for acid and 173.56 ppm for ester. (author)

  18. Toughening of biodegradable polylactide/poly(butylene succinate-co-adipate) blends via in situ reactive compatibilization

    CSIR Research Space (South Africa)

    Ojijo, Vincent O

    2013-04-01

    Full Text Available of parameters such as the mixing sequence and time, TPP content, and PBSA concentration revealed that blends containing 30 and 10 wt % PBSA and 2 wt % TPP, which were processed for 30 min, were optimal in terms of thermomechanical properties. The impact strength...

  19. GC-MS ANALYSIS OF THE FATTY ACID METHYL ESTER IN JAPANESE QUAIL FAT

    Directory of Open Access Journals (Sweden)

    Ion Dragalin

    2015-12-01

    Full Text Available The accumulated as production waste fat from Faraon quail breeds has been investigated for the first time by using GC-MS technique, preventively converting it via methanolysis to fatty acid methyl esters. The test results, regarding the content of unsaturated fatty acids having a favorable to human body cis-configuration (77.8%, confirm their nutritional value and the possibility of using this fat in cosmetic, pharmaceutical and food industries.

  20. Transesterification Synthesis of Chloramphenicol Esters with the Lipase from Bacillus amyloliquefaciens

    Directory of Open Access Journals (Sweden)

    Fengying Dong

    2017-09-01

    Full Text Available This work presents a synthetic route to produce chloramphenicol esters by taking advantage the high enantio- and regio-selectivity of lipases. A series of chloramphenicol esters were synthesized using chloramphenicol, acyl donors of different carbon chain length and lipase LipBA (lipase cloned from Bacillus amyloliquefaciens. Among acyl donors with different carbon chain lengths, vinyl propionate was found to be the best. The influences of different organic solvents, reaction temperature, reaction time, enzyme loading and water content on the synthesis of the chloramphenicol esters were studied. The synthesis of chloramphenicol propionate (0.25 M with 4.0 g L−1 of LipBA loading gave a conversion of ~98% and a purity of ~99% within 8 h at 50 °C in 1,4-dioxane as solvent. The optimum mole ratio of vinyl propionate to chloramphenicol was increased to 5:1. This is the first report of B. amyloliquefaciens lipase being used in chloramphenicol ester synthesis and a detailed study of the synthesis of chloramphenicol propionate using this reaction. The high enzyme activity and selectivity make lipase LipBA an attractive catalyst for green chemical synthesis of molecules with complex structures.

  1. Analysis of chemical signatures of alkaliphiles using fatty acid methyl ester analysis

    Directory of Open Access Journals (Sweden)

    Basha Sreenivasulu

    2017-01-01

    Full Text Available Background: Fatty acids occur in nearly all living organisms as the important predominant constituents of lipids. While all fatty acids have essentially the same chemical nature, they are an extremely diverse group of compounds. Materials and Methods: To test the hypothesis, fatty acids of alkaliphiles isolates, Bacillus subtilis SVUNM4, Bacillus licheniformis SVUNM8, Bacillus methylotrohicus SVUNM9, and Paenibacillus dendritiformis SVUNM11, were characterized compared using gas chromatography-mass spectrometry (GC-MS analysis. Results: The content of investigated ten fatty acids, 1, 2-benzenedicarboxylic acid butyl 2-methylpropyl ester, phthalic acid, isobutyl 2-pentyl ester, dibutyl phthalate, cyclotrisiloxane, hexamethyl, cyclotetrasiloxane, octamethyl, dodecamethyl, heptasiloxane 1,1,3,3,5,5,7,7,9,9,11,11,13,13-etradecamethyl, 7,15-dihydroxydehydroabietic acid, methyl ester, di (trimethylsilyl ether, hentriacontane, 2-thiopheneacetic acid, undec-2-enyl ester, obviously varied among four species, suggesting each species has its own fatty acid pattern. Conclusions: These findings demonstrated that GC-MS-based fatty acid profiling analysis provides the reliable platform to classify these four species, which is helpful for ensuring their biotechnological interest and novel chemotaxonomic.

  2. Quantitative analysis of anti-inflammatory and radical scavenging triterpenoid esters in evening primrose seeds.

    Science.gov (United States)

    Zaugg, Janine; Potterat, Olivier; Plescher, Andreas; Honermeier, Bernd; Hamburger, Matthias

    2006-09-06

    Lipophilic triterpenoidal esters with radical scavenging and cyclooxygenase inhibitory properties were recently found in cold-pressed, nonraffinated evening primrose oil (EPO). A quantitative assay for the analysis of 3-O-trans-caffeoyl derivatives of betulinic, morolic, and oleanolic acid in evening primrose seeds was developed and validated. Extraction efficiency >99% was achieved by means of pressurized liquid extraction with two extraction cycles and 80% (v/v) ethanol at 120 degrees C. Analysis of esters was by normal-phase high-performance liquid chromatography on a Diol column and hexane/ethyl acetate (containing 0.1% formic acid) (65:35) as the eluent. The analytes were determined without further prepurification. Seeds from defined cultures of Oenothera biennis, Oenothera lamarckiana, and Oenothera ammophila, grown under identical conditions, were analyzed. The cultures originated from seeds from eight collections in the wild and from selections from five cultivars. The content of total triterpenoidal esters in seeds varied between 1.34 and 2.78 mg/g. Three types of qualitative patterns were observed for the triterpenoidal esters. The influence of different harvest times and plant treatments was studied with the cultivar Anothera. Variations between 1.5 and 2.3 mg/g were found.

  3. Stability and changes in astaxanthin ester composition from Haematococcus pluvialis during storage

    Science.gov (United States)

    Miao, Fengping; Geng, Yahong; Lu, Dayan; Zuo, Jincheng; Li, Yeguang

    2013-11-01

    In this paper, we investigated the effects of temperature, oxygen, antioxidants, and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions, and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry. Oxygen and high temperatures (22-25°C) significantly reduced the stability of astaxanthin esters. Corn germ oil and antioxidants (ascorbic acid and vitamin E) failed to protect astaxanthin from oxidation, and actually significantly increased the instability of astaxanthin. A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage. During storage, the relative amounts of free astaxanthin and astaxanthin monoesters declined, while the relative amount of astaxanthin diesters increased. Thus, the ratio of astaxanthin diester to monoester increased, and this ratio could be used to indicate if astaxanthin esters have been properly preserved. If the ratio is greater than 0.2, it suggests that the decrease in astaxanthin content could be higher than 20%. Our results show that storing algal powder from H. pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H. pluvialis. This storage method can produce an astaxanthin preservation rate of at least 80% after 96 weeks of storage.

  4. Identification and dosage by HRGC of minor alcohols and esters in Brazilian sugar-cane spirit

    Directory of Open Access Journals (Sweden)

    Boscolo Maurício

    2000-01-01

    Full Text Available The presence of 51 volatile compounds, among alcohols and esters in Brazilian sugar-cane spirit (cachaça, were investigated by high-resolution gas chromatography (HRGC. The following alcohols and esters were identified and quantified: methanol, 1,4-butanodiol, 2-phenylethyl alcohol, amyl alcohol, cetyl alcohol, cynamic alcohol, n-decanol, geraniol, isoamyl alcohol, isobutanol, menthol, n-butanol, n-dodecanol, n-propanol, n-tetradecanol, amyl propionate, ethyl acetate, ethyl benzoate, ethyl heptanoate, isoamyl valerate, methyl propionate, propyl butyrate. The average higher alcohols content (262 mg/100 mL in anhydrous alcohol a.a. and total esters content (24 mg/100 mL a.a. in cachaças, are smaller than in other spirits. The average methanol content in cachaças (6 mg/100 mL a.a. is the same as in rum, but smaller than in wine spirit. No qualitative differences of chemical profile among cachaças have been observed.

  5. Enzymatic synthesizing of phytosterol oleic esters.

    Science.gov (United States)

    Pan, Xinxin; Chen, Biqiang; Wang, Juan; Zhang, Xinzhi; Zhul, Biyun; Tan, Tianwei

    2012-09-01

    A method of synthesizing the phytosterol esters from oleic acid and sterols was studied, using immobilized lipase Candida sp. 99-125 as catalyst. Molar ratio (oleic acid/phytosterols), temperature, reaction period, organic solvents, catalyst, and silica-gel drier were optimized, and the result showed that 93.4% of the sterols had been esterified under the optimal synthetic condition: the molar ratio of oleic acid/phytosterol is 1:1 in 10 mL iso-octane, immobilized lipase (w, 140% of the sterols), incubated in an orbital shaker (200 rpm) at a temperature of 45 °C for 24 h. The immobilized lipase could be reused for at least 13 times with limited loss of esterification activity. The conversion still maintained up to 86.6%. Hence, this developed process for synthesizing phytosterol esters could be considered as simple and low-energy consumption compared to existing chemical processes.

  6. Naturally occurring antifungal aromatic esters and amides

    International Nuclear Information System (INIS)

    Ali, M.S.; Shahnaz; Tabassum, S.; Ogunwande, I.A.; Pervez, M.K.

    2010-01-01

    During the search of antifungal natural products from terrestrial plants, a new long chained aromatic ester named grandiflorate along with spatazoate from Portulaca grandiflora and N-[2-methoxy-2-(4-methoxyphenyl) ethyl]-trans-cinnamide and aegeline from Solanum erianthum of Nigeria were isolated and tested against six fungal species. The known constituents have not been reported so far from mentioned investigated plants. Structures of the isolated compounds were elucidated with the aid of spectroscopic techniques including two dimensional NMR experiments. Among the compounds, the esters found more potent than amides against Candida albicans and Aspergillus flavus. The new compound grandiflorate gave response against all tested fungal species while aegeline was found to give lowest inhibition during this study. (author)

  7. Naturally occurring antifungal aromatic esters and amides

    Energy Technology Data Exchange (ETDEWEB)

    Ali, M S; Shahnaz,; Tabassum, S; Ogunwande, I A; Pervez, M K [University of Karachi (Pakistan). HEJ Research Inst. of Chemistry, International Centre for Chemical and Biological Sciences

    2010-08-15

    During the search of antifungal natural products from terrestrial plants, a new long chained aromatic ester named grandiflorate along with spatazoate from Portulaca grandiflora and N-[2-methoxy-2-(4-methoxyphenyl) ethyl]-trans-cinnamide and aegeline from Solanum erianthum of Nigeria were isolated and tested against six fungal species. The known constituents have not been reported so far from mentioned investigated plants. Structures of the isolated compounds were elucidated with the aid of spectroscopic techniques including two dimensional NMR experiments. Among the compounds, the esters found more potent than amides against Candida albicans and Aspergillus flavus. The new compound grandiflorate gave response against all tested fungal species while aegeline was found to give lowest inhibition during this study. (author)

  8. Atmospheric oxidation of selected alcohols and esters

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K H; Cavalli, F

    2001-03-01

    The decision whether it is appropriate and beneficial for the environment to deploy specific oxygenated organic compounds as replacements for traditional solvent types requires a quantitative assessment of their potential atmospheric impacts including tropospheric ozone and other photooxidant formation. This involves developing chemical mechanisms for the gasphase atmospheric oxidation of the compounds which can be reliably used in models to predict their atmospheric reactivity under a variety of environmental conditions. Until this study, there was very little information available concerning the atmospheric fate of alcohols and esters. The objectives of this study were to measure the atmospheric reaction rates and to define atmospheric reaction mechanisms for the following selected oxygenated volatile organic compounds: the alcohols, 1-butanol and 1-pentanol, and the esters, methyl propionate and dimethyl succinate. The study has successfully addressed these objectives. (orig.)

  9. Cytosolic cholesterol ester hydrolase in adrenal cortex

    OpenAIRE

    Tocher, Douglas R.

    1983-01-01

    Cholesterol ester hydrolase (CEH) in adrenocortical cytosol was known to be phosphorylated and activated, in response to ACTH in a cAMPdependent protein kinase mediated process. The purification of CEH from bovine adrenocortical cytosol was attempted. The use of detergents to solubilise the enzyme from lipid-rich aggregates was investigated and sodium cholate was found to be effective. A purification procedure using cholate solubilised enzyme was developed. The detergent int...

  10. Synthetic Methods for Ester Bond Formation and Conformational Analysis of Ester-Containing Carbohydrates

    Science.gov (United States)

    Hackbusch, Sven

    This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general. Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity dependent on the presence or absence of an achiral amine catalyst. In particular, this work establishes a structure-activity relationship with regard to the trans-2-substituent and its role as a chiral auxiliary in the reversal of diastereoselectivity. In the second part, the synthesis of various ester-linked carbohydrate derivatives, and their conformational analysis is presented. Using multidimensional NMR experiments and computational methods, the compounds' solution-phase structures were established and the effect of the ester functional group on the molecules' flexibility and three-dimensional (3D) structure was investigated and compared to ether or glycosidic linkages. To aid in this, a novel Karplus equation for the C(sp2)OCH angle in ester-linked carbohydrates was developed on the basis of a model ester-linked carbohydrate. This equation describes the sinusoidal relationship between the C(sp2)OCH dihedral angle and the corresponding 3JCH coupling constant that can be determined from a J-HMBC NMR experiment. The insights from this research will be useful in describing the 3D structure of naturally occurring and lab-made ester-linked derivatives of carbohydrates, as well as guiding the de novo-design of

  11. Methyl and ethyl soybean esters production

    Energy Technology Data Exchange (ETDEWEB)

    Pighinelli, Anna Leticia Montenegro Turtelli; Park, Kil Jin; Zorzeto, Thais Queiroz [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola], E-mail: annalets@feagri.unicamp.br; Bevilaqua, Gabriela [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

    2008-07-01

    Biodiesel is a fuel obtained from triglycerides found in nature, like vegetable oils and animal fats. Nowadays it has been the subject of many researches impulses by the creation of the Brazilian law that determined the blend of 2% of biodiesel with petrodiesel. Basically, there are no limitations on the oilseed type for chemical reaction, but due to high cost of this major feedstock, it is important to use the grain that is available in the region of production. Soybean is the oilseed mostly produced in Brazil and its oil is the only one that is available in enough quantity to supply the current biodiesel demand. The objective of this work was to study the effects of reaction time and temperature on soybean oil transesterification reaction with ethanol and methanol. A central composite experimental design with five variation levels was used and response surface methodology applied for the data analysis. The statistical analysis of the results showed that none of the factors affected the ethyl esters production. However, the methyl esters production suffered the influence of temperature (linear effect), reaction time (linear and quadratic) and interaction of these two variables. None of the generated models showed significant regression consequently it was not possible to build the response surface. The experiments demonstrated that methanol is the best alcohol for transesterification reactions and the ester yield was up to 85%. (author)

  12. Screening of adjunct cultures and their application in ester formation in Camembert-type cheese.

    Science.gov (United States)

    Hong, Q; Liu, X M; Hang, F; Zhao, J X; Zhang, H; Chen, W

    2018-04-01

    The ethanol content and esterase and alcohol acyltransferase activities are the limiting factors in the synthesis of ethyl esters in Camembert-type cheeses. This study aimed to investigate the effects of alcohol, esterase and alcohol acyltransferase activities on ethyl ester formation in Camembert-type cheeses. Five experimental cheeses were prepared with three adjunct cultures with different enzyme activities and two levels of ethanol content (400 or 800 μg/g). The cheeses were aged for 4 weeks and analysed weekly for basic physicochemical, textural, volatile and sensory properties. The results showed that both the enzyme activity and ethanol content were limiting factors in the synthesis of ethyl esters in the Camembert-type cheeses. Variation in the esterase synthesis activity was observed among lactic acid bacteria, and the starter culture Lactococcus lactis MA 14 LYO distinguished itself through its high acidifying and esterase hydrolysis abilities. The addition of CCFM 12, a lactic acid bacteria strain with high esterase and alcohol acyltransferase activity, along with 400 or 800 μg/g of ethanol, notably enhanced the generation of ethyl esters and the corresponding fruity flavour, without causing dramatic changes in the basic physicochemical indices and microbial profile. In addition, cohesiveness was influenced by the addition of 400 and 800 μg/g of ethanol, and more resilience with 800 μg/g of ethanol had been found. The results showed that the addition of CCFM12 with 400 and 800 μg/g of ethanol may be applied in the production of Camembert cheese to enhance its fruity flavour. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Environmentally friendly properties of vegetable oil methyl esters

    Directory of Open Access Journals (Sweden)

    Gateau Paul

    2005-07-01

    Full Text Available Measurements were carried out on Vegetable Oil Methyl Esters (VOME or FAME answering the most recent specifications. The products tested are RME (Rapeseed oil Methyl Ester, ERME (Erucic Rapeseed oil Methyl Esters, SME (Sunflower oil Methyl Esters, and HOSME (High Oleic Sunflower oil Methyl Esters. They contain more than 99.5% of fatty acid mono esters. The compositions are given. VOME are not volatile and they are not easily flammable. They are not soluble in water and they are biodegradable. According to the methods implemented for the determination of the German classification of substances hazardous to waters WGK, they are not toxic on mammals and unlike diesel fuel they are not toxic on fish, daphnia, algae and bacteria. The RME is not either toxic for shrimps. According to tests on rabbits, RME and SME are not irritating for the skin and the eyes. VOME display particularly attractive environmental properties.

  14. Apple Aminoacid Profile and Yeast Strains in the Formation of Fusel Alcohols and Esters in Cider Production.

    Science.gov (United States)

    Eleutério Dos Santos, Caroline Mongruel; Pietrowski, Giovana de Arruda Moura; Braga, Cíntia Maia; Rossi, Márcio José; Ninow, Jorge; Machado Dos Santos, Tâmisa Pires; Wosiacki, Gilvan; Jorge, Regina Maria Matos; Nogueira, Alessandro

    2015-06-01

    The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3-methyl-1-butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation. © 2015 Institute of Food Technologists®

  15. Osteoconductive bio-based meshes based on Poly(hydroxybutyrate-co-hydroxyvalerate) and poly(butylene adipate-co-terephthalate) blends

    International Nuclear Information System (INIS)

    Nar, Mangesh; Staufenberg, Gerrit; Yang, Bing; Robertson, Lesli; Patel, Rinkesh H.; Varanasi, Venu G.; D'Souza, Nandika Anne

    2014-01-01

    Poly(butylene adipate-co-terephthalate) (PBAT) and Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) are biopolymers that have the potential to be used in applications of bone healing. In this study, it is hypothesized that the polymer blend has the combined strength and osteoconductivity to support osteoblast collagen formation. PBAT (PBAT 100), and a blend with 20% PHBV (PBAT 80) were extruded in the form of fibers and then knitted in the form of mesh. These were tested in the warp as well as weft direction for the tensile properties; these showed that the weft direction had higher performance than the warp. The individual fibers were kept in phosphate buffered saline (PBS) over the period of 8 weeks and were tested for the storage and loss modulus using a dynamic mechanical analyser (DMA). The results indicated that mechanical relaxation strength showed a decrease and then an increase. In vitro osteoconductivity studies were done by using differentiating osteoblasts (MC3T3-E1 subclone 4 cells). Environmental Scanning Electron Microscopy (ESEM) showed that pre-soaking the samples in α-MEM for two weeks resulted in cell attachment and growth. X-ray diffraction (XRD) was used to determine the change in structure of polymers due to in vitro degradation for two weeks. Raman spectroscopy showed that all scaffolds supported the formation of a collagenous network over the scaffold surfaces. For a combination of knittable manufacturing, mechanical performance and osteoconductivity, blends offer an effective route. - Highlights: • PBAT and PHBV blend can be knitted to form mesh with good mechanical properties. • PBAT and PHBV blend do not show significant weight loss over a period of 8 weeks in PBS. • Osteoblast cell culture was done on these samples. • They support extracellular matrix and growth and hence are osteoconductive

  16. Osteoconductive bio-based meshes based on Poly(hydroxybutyrate-co-hydroxyvalerate) and poly(butylene adipate-co-terephthalate) blends

    Energy Technology Data Exchange (ETDEWEB)

    Nar, Mangesh; Staufenberg, Gerrit; Yang, Bing [Department of Material Science and Engineering, University of North Texas, 1155 Union Circle #305310, Denton, TX 76203-5017 (United States); Robertson, Lesli [Department of Fibers, College of Visual Arts and Design, 1155 Union Circle #305100, Denton, TX 76203-5017 (United States); Patel, Rinkesh H. [Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A and M University Baylor College of Dentistry, Dallas, TX 75246 (United States); Varanasi, Venu G., E-mail: vvaranasi@bcd.tamhsc.edu [Department of Biomedical Sciences and Center for Craniofacial Research and Diagnosis, Texas A and M University Baylor College of Dentistry, Dallas, TX 75246 (United States); D' Souza, Nandika Anne, E-mail: nandika.dsouza@unt.edu [Department of Material Science and Engineering, University of North Texas, 1155 Union Circle #305310, Denton, TX 76203-5017 (United States); Department of Mechanical and Energy Engineering, University of North Texas, 1155 Union Circle # 311098, Denton, TX 76203-5017 (United States)

    2014-05-01

    Poly(butylene adipate-co-terephthalate) (PBAT) and Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) are biopolymers that have the potential to be used in applications of bone healing. In this study, it is hypothesized that the polymer blend has the combined strength and osteoconductivity to support osteoblast collagen formation. PBAT (PBAT 100), and a blend with 20% PHBV (PBAT 80) were extruded in the form of fibers and then knitted in the form of mesh. These were tested in the warp as well as weft direction for the tensile properties; these showed that the weft direction had higher performance than the warp. The individual fibers were kept in phosphate buffered saline (PBS) over the period of 8 weeks and were tested for the storage and loss modulus using a dynamic mechanical analyser (DMA). The results indicated that mechanical relaxation strength showed a decrease and then an increase. In vitro osteoconductivity studies were done by using differentiating osteoblasts (MC3T3-E1 subclone 4 cells). Environmental Scanning Electron Microscopy (ESEM) showed that pre-soaking the samples in α-MEM for two weeks resulted in cell attachment and growth. X-ray diffraction (XRD) was used to determine the change in structure of polymers due to in vitro degradation for two weeks. Raman spectroscopy showed that all scaffolds supported the formation of a collagenous network over the scaffold surfaces. For a combination of knittable manufacturing, mechanical performance and osteoconductivity, blends offer an effective route. - Highlights: • PBAT and PHBV blend can be knitted to form mesh with good mechanical properties. • PBAT and PHBV blend do not show significant weight loss over a period of 8 weeks in PBS. • Osteoblast cell culture was done on these samples. • They support extracellular matrix and growth and hence are osteoconductive.

  17. Super-Robust Polylactide Barrier Films by Building Densely Oriented Lamellae Incorporated with Ductile in Situ Nanofibrils of Poly(butylene adipate-co-terephthalate).

    Science.gov (United States)

    Zhou, Sheng-Yang; Huang, Hua-Dong; Ji, Xu; Yan, Ding-Xiang; Zhong, Gan-Ji; Hsiao, Benjamin S; Li, Zhong-Ming

    2016-03-01

    Remarkable combination of excellent gas barrier performance, high strength, and toughness was realized in polylactide (PLA) composite films by constructing the supernetworks of oriented and pyknotic crystals with the assistance of ductile in situ nanofibrils of poly(butylene adipate-co-terephthalate) (PBAT). On the basis that the permeation of gas molecules through polymer materials with anisotropic structure would be more frustrated, we believe that oriented crystalline textures cooperating with inerratic amorphism can be favorable for the enhancement of gas barrier property. By taking full advantage of intensively elongational flow field, the dispersed phase of PBAT in situ forms into nanofibrils, and simultaneously sufficient row-nuclei for PLA are induced. After appropriate thermal treatment with the acceleration effect of PBAT on PLA crystallization, oriented lamellae of PLA tend to be more perfect in a preferential direction and constitute into a kind of network interconnecting with each other. At the same time, the molecular chains between lamellae tend to be more extended. This unique structure manifests superior ability in ameliorating the performance of PLA film. The oxygen permeability coefficient can be achieved as low as 2 × 10(-15) cm(3) cm cm(-2) s(-1) Pa(-1), combining with the high strength, modulus, and ductility (104.5 MPa, 3484 MPa, and 110.6%, respectively). The methodology proposed in this work presents an industrially scalable processing method to fabricate super-robust PLA barrier films. It would indeed push the usability of biopolymers forward, and certainly prompt wider application of biodegradable polymers in the fields of environmental protection such as food packaging, medical packaging, and biodegradable mulch.

  18. Isolation and identification of an ester from a crude oil

    Science.gov (United States)

    Phillips, H.F.; Breger, I.A.

    1958-01-01

    A dioctylphthalate has been isolated from a crude oil by means of adsorption column chromatography. The ester was identified by means of elemental analysis, refractive index, and its infra-red absorption spectrum. Saponification of the isolate and examination of the resultant alcohol by means of infrared absorption spectra led to the conclusion that the ester is a branched chain dioctylphthalate. This is the first reported occurrence of an ester in crude petroleum. ?? 1958.

  19. Mutagenic activity of phthalate esters in bacterial liquid suspension assays.

    OpenAIRE

    Seed, J L

    1982-01-01

    The mutagenic activities of several phthalate esters have been evaluated in an 8-azaguanine resistance assay in Salmonella typhimurium. Three phthalate esters were found to be mutagenic: dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate. A number of other phthalate esters were not found to be mutagenic, including di(2-ethylhexyl) phthalate, di-n-octyl phthalate, diallyl phthalate, diisobutyl phthalate and diisodecyl phthalate. A metabolite of di(2-ethylhexyl) phthalate, 2-ethylhe...

  20. Identification of 3-MCPD esters to verify the adulteration of extra virgin olive oil.

    Science.gov (United States)

    Hung, Wei-Ching; Peng, Guan-Jhih; Tsai, Wen-Ju; Chang, Mei-Hua; Liao, Chia-Ding; Tseng, Su-Hsiang; Kao, Ya-Min; Wang, Der-Yuan; Cheng, Hwei-Fang

    2017-09-01

    The adulteration of olive oil is an important issue around the world. This paper reports an indirect method by which to identify 3-monochloropropane-1,2-diol (3-MCPD) esters in olive oils. Following sample preparation, the samples were spiked with 1,2-bis-palmitoyl-3-chloropropanediol standard for analysis using gas chromatograph-tandem mass spectrometry. The total recovery ranged from 102.8% to 105.5%, the coefficient of variation ranged from 1.1% to 10.1%, and the limit of quantification was 0.125 mg/kg. The content of 3-MCPD esters in samples of refined olive oil (0.97-20.53 mg/kg) exceeded those of extra virgin olive oil (non-detected to 0.24 mg/kg). These results indicate that the oil refining process increased the content of 3-MCPD esters, which means that they could be used as a target compound for the differentiation of extra virgin olive oil from refined olive oil in order to prevent adulteration.

  1. Investigation of bifunctional ester additives for methanol-gasoline system

    International Nuclear Information System (INIS)

    Zhang, J.; Yang, C.; Tang, Y.; Du, Q.; Song, N.; Zhang, Z.

    2014-01-01

    To explore new and multifunctional additives for methanol-gasoline, tartaric ester were synthesized and screened as phase stabilizer and saturation vapor pressure depressor for methanol-gasoline. The effect of the esters structure on the efficiency was discussed. The results show that the stabilities of the blends depend on the length of the glycolic esters alkoxy group. In addition, the tartaric esters also can depress the saturation vapor pressure of methanol-gasoline effectively in M15. Effect of the structure on the efficiency was also discussed. (author)

  2. Estereótipos e mulheres na cultura marroquina

    OpenAIRE

    Sadiqi,Fatima

    2008-01-01

    Estereótipos sobre as mulheres no Marrocos podem ser caracterizados como crenças culturais incompletas e inexatas mantidas por algumas pessoas e que se encontram inscritos em expressões lingüísticas ou em discursos subliminares. A cultura popular marroquina emprega representações poderosas para transmitir e sustentar tais estereótipos. Embora existam alguns estereótipos positivos, a maioria dos estereótipos sobre as mulheres no Marrocos é negativa e reflete ditames patriarcais subliminares qu...

  3. Emission and Mechanical Evaluations of Vinyl-Ester Resin Systems

    National Research Council Canada - National Science Library

    Sands, James

    2003-01-01

    Vinyl-ester resins (VE) are frequently used in liquid molding of composite materials for several applications including naval and army structures, commercial boat manufacturing, and building construction...

  4. Direct determination of 3-chloropropanol esters in edible vegetable oils using high resolution mass spectrometry (HRMS-Orbitrap).

    Science.gov (United States)

    Graziani, Giulia; Gaspari, Anna; Chianese, Donato; Conte, Lanfranco; Ritieni, Alberto

    2017-11-01

    A series of refined edible oils derived from mixed seeds, peanuts, corn, sunflower and palm obtained from the local supermarket were analyzed for their content of 3-MCPD esters. A direct analytical method for the determination of 3-monochloropropane-1,2-diol esters (3-MCPD esters) was applied to investigate the major MCPD esters found in common edible oils; in particular seven types of monoesters and eleven types of diesters were detected. The limits of detection (LODs) for monoesters and diesters of 3-MCPD were in the range of 0.079-12.678 µg kg -1 and 0.033-18.610 µg kg -1 in edible oils, and the ranges of limits of quantitation (LOQs) were 0.979-38.035 µg kg -1 and 0.100-55 µg kg -1 , respectively. The recoveries of 3-MCPD esters from oil samples were in the range of 80-100%, with RSD ranging between 1.9 and 11.8%. The concentration levels of total 3-MCPD diesters in vegetable oil samples were in the range from 0.106 up to 3.444 μg g -1 whereas total monoesters ranged from 0.005 up to 1.606 μg g -1 .

  5. Half esters and coating compositions comprising reactions products of half esters and polyepoxides

    NARCIS (Netherlands)

    Blaauw, R.; Mulder, W.J.; Koelewijn, R.; Boswinkel, G.

    2006-01-01

    The present invention relates to half esters based on dicarboxylic acid derivatives and dimer fatty diols, wherein the dimer fatty dio ls are based on dimerised and/or trimerised and/or oligomerised unsaturated fatty acids. The present invention further relates to resin compositions based on the

  6. Occurrence of 3-monochloropropanediol esters and glycidyl esters in commercial infant formulas in the United States.

    Science.gov (United States)

    Leigh, Jessica; MacMahon, Shaun

    2017-03-01

    This work presents occurrence data for fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD) and glycidol in 98 infant formula samples purchased in the United States. These contaminants are considered potentially carcinogenic and/or genotoxic, making their presence in refined oils and foods a potential health risk. Recently, attention has focused on methodology to quantify MCPD and glycidyl esters in infant formula for risk-assessment purposes. Occurrence data for 3-MCPD and glycidyl esters were produced using a procedure for extracting fat from infant formula and an LC-MS/MS method for analysing fat extracts for intact esters. Infant formulas were produced by seven manufacturers, five of which use palm oil and/or palm olein in their formulations. In formulas containing palm/palm olein, concentrations for bound 3-MCPD and glycidol ranged from 0.021 to 0.92 mg kg - 1 (ppm) and from 3-MCPD and glycidol concentrations ranged from 0.072 to 0.16 mg kg - 1 (ppm) and from 0.005 to 0.15 mg kg - 1 (ppm), respectively. Although formulas from manufacturers A and G did not contain palm/palm olein, formulas from manufacturer E (containing palm olein) had the lowest concentrations of bound 3-MCPD and glycidol, demonstrating the effectiveness of industrial mitigation strategies.

  7. Stanol esters attenuate the aggravating effect of dietary cholesterol on atherosclerosis in homozygous Watanabe rabbits

    DEFF Research Database (Denmark)

    Schrøder, Malene; Husche, Constanze; Pilegaard, Kirsten

    2009-01-01

    Plant stanols are marketed as natural means to lower blood cholesterol in humans; hence the effect on combined familial hyperlipidemia is not known. The objective was to investigate the effect of stanol esters on blood lipids and aortic atherosclerosis in homozygous WHHL rabbits challenged...... with dietary cholesterol. A total of 36 rabbits, 6 weeks of age, with initial plasma cholesterol of 22.5 mmol/L were assigned to two treatment groups fed a standard rabbit chow with 1 g/kg cholesterol or this diet added 34 g/kg stanol ester, respectively, for 16 weeks. Plasma cholesterol was measured initially...... and at termination, also in lipoproteins. Aortic atherosclerosis was evaluated as cholesterol content and area covered by plaque. Plasma cholesterol was not significantly different between the groups at termination (35.7 mmol/L vs. 35.5 mmol/L). A significant increase in LDL was seen (13.1 mmol/L vs. 16.5 mmol...

  8. Transcription profile data of phorbol esters biosynthetic genes during developmental stages in Jatropha curcas.

    Science.gov (United States)

    Jadid, Nurul; Mardika, Rizal Kharisma; Purwani, Kristanti Indah; Permatasari, Erlyta Vivi; Prasetyowati, Indah; Irawan, Mohammad Isa

    2018-06-01

    Jatropha curcas is currently known as an alternative source for biodiesel production. Beside its high free fatty acid content, J. curcas also contains typical diterpenoid-toxic compounds of Euphorbiaceae plant namely phorbol esters. This article present the transcription profile data of genes involved in the biosynthesis of phorbol esters at different developmental stages of leaves, fruit, and seed in Jatropha curcas . Transcriptional profiles were analyzed using reverse transcription-polymerase chain reaction (RT-PCR). We used two genes including GGPPS (Geranylgeranyl diphospate synthase), which is responsible for the formation of common diterpenoid precursor (GGPP) and CS (Casbene Synthase), which functions in the synthesis of casbene. Meanwhile, J. curcas Actin ( ACT ) was used as internal standard. We demonstrated dynamic of GGPPS and CS expression among different stage of development of leaves, fruit and seed in Jatropha .

  9. USAGE OF METHYL ESTER PRODUCED FROM WASTE GRAPE AND MN ADDITIVE AS ALTERNATIVE DIESEL FUEL

    Directory of Open Access Journals (Sweden)

    Hanbey Hazar

    2017-06-01

    Full Text Available In this study, methyl ester was produced from waste grape pulp sources. The produced methyl ester was mixed with diesel in different proportions, and was tested for engine performance and emission. It was found that with increasing biodiesel content, the specific fuel consumption and exhaust temperature have increased partially, while the CO, HC and smoke emissions decreased significantly. Additionally, in the scope of this study, dodecanol, propylene glycol and Mn based additives were added to fuel B50 to improve the emission and engine performance values. With the presence of additives, an increase in the exhaust temperature was observed, while a decrease in the specific fuel consumption, CO, HC, and smoke emissions were detected.

  10. Transesterification of rubber seed oil by sonication technique for the production of methyl esters

    Energy Technology Data Exchange (ETDEWEB)

    Ragavan, S.N.; Roy, D.V. [Scott Christian College (Autonomous), Department of Chemistry, Research Centre, Nagercoil, Tamil Nadu (India)

    2011-07-15

    The ever-increasing concern due to the fast-depleting energy sources and the environmental impact of the fossil fuel burning has provoked the researchers to turn out for an environmentally benign fuel source. Biodiesel (fatty acid methyl esters) being renewable, biodegradable, non-toxic and eco-friendly, is now gaining momentum. Added carbon sequestration ability of rubber trees has made it one of the best sources for biodiesel in developing countries. Fatty acid methyl esters (FAMEs) from high acid content (23%) rubber seed oil by sonication technique at room temperature (32 C) is of good yield (80%). The FAMEs produced have acceptable fuel standards as specified by ASTM D 6751. This study deals with the utilisation of FAMEs as an alternate fuel for petrodiesel. (orig.)

  11. Measurement uncertainty of ester number, acid number and patchouli alcohol of patchouli oil produced in Yogyakarta

    Science.gov (United States)

    Istiningrum, Reni Banowati; Saepuloh, Azis; Jannah, Wirdatul; Aji, Didit Waskito

    2017-03-01

    Yogyakarta is one of patchouli oil distillation center in Indonesia. The quality of patchouli oil greatly affect its market price. Therefore, testing quality of patchouli oil parameters is an important concern, one through determination of the measurement uncertainty. This study will determine the measurement uncertainty of ester number, acid number and content of patchouli alcohol through a bottom up approach. Source contributor to measurement uncertainty of ester number is a mass of the sample, a blank and sample titration volume, the molar mass of KOH, HCl normality, and replication. While the source contributor of the measurement uncertainty of acid number is the mass of the sample, the sample titration volume, the relative mass and normality of KOH, and repetition. Determination of patchouli alcohol by Gas Chromatography considers the sources of measurement uncertainty only from repeatability because reference materials are not available.

  12. Transesterification of mustard (Brassica nigra) seed oil with ethanol: Purification of the crude ethyl ester with activated carbon produced from de-oiled cake

    International Nuclear Information System (INIS)

    Fadhil, Abdelrahman B.; Abdulahad, Waseem S.

    2014-01-01

    Highlights: • Biodiesel ethyl ester has been developed from mustard seed oil. • Variables affect the transesterification were investigated. • Dry washing using the activated carbon produced from the extraction remaining was applied to purify the ethyl esters. • Properties of the produced fuels were measured. • Blending of the produced ethyl ester with petro diesel was also investigated. - Abstract: The present study reports the production of mustard seed oil ethyl esters (MSOEE) through alkali-catalyzed transesterification with ethanol using potassium hydroxide as a catalyst. The influence of the process parameters such as catalyst concentration, ethanol to oil molar ratio, reaction temperature, reaction duration and the catalyst type was investigated so as to find out the optimal conditions for the transesterification process. As a result, optimum conditions for production of MSOEE were found to be: 0.90% KOH wt/wt of oil, 8:1 ethanol to oil molar ratio, a reaction temperature of 60 °C, and a reaction time of 60 min. Dry washing method with (2.50% wt.) of the activated carbon that was produced from the de-oiled cake was used to purify the crude ethyl ester from the residual catalyst and glycerol. The transesterification process provided a yield of 94% w/w of ethyl esters with an ester content of 98.22% wt. under the optimum conditions. Properties of the produced ethyl esters satisfied the specifications prescribed by the ASTM standards. Blending MSOEE with petro diesel was also investigated. The results showed that the ethyl esters had a slight influence on the properties of petro diesel

  13. Neutral Lipid Biosynthesis in Engineered Escherichia coli: Jojoba Oil-Like Wax Esters and Fatty Acid Butyl Esters

    OpenAIRE

    Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

    2006-01-01

    Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant E...

  14. Are Polyphosphates or Phosphate Esters Prebiotic Reagents?

    Science.gov (United States)

    Keefe, Anthony D.; Miller, Stanley L.

    1995-01-01

    It is widely held that there was a phosphate compound in prebiotic chemistry that played the role of adenosine triphosphate and that the first living organisms had ribose-phosphate in the backbone of their genetic material. However, there are no known efficient prebiotic synthesis of high-energy phosphates or phosphate esters. We review the occurrence of phosphates in nature, the efficiency of the volcanic synthesis of P4O10, the efficiency of polyphosphate synthesis by heating phosphate minerals under geological conditions, and the use of high-energy organic compounds such as cyanamide or hydrogen cyanide. These are shown to be inefficient processes especially when the hydrolysis of the polyphosphates is taken into account. For example, if a whole atmosphere of methane or carbon monoxide were converted to cyanide which somehow synthesized polyphosphates quantitatively, the polyphosphate concentration in the ocean would still have been insignificant. We also attempted to find more efficient high-energy polymerizing agents by spark discharge syntheses, but without success. There may still be undiscovered robust prebiotic syntheses of polyphosphates, or mechanisms for concentrating them, but we conclude that phosphate esters may not have been constituents of the first genetic material. Phosphoanhydrides are also unlikely as prebiotic energy sources.

  15. Lipid sac area as a proxy for individual lipid content of arctic calanoid copepods

    OpenAIRE

    Vogedes, Daniel; Varpe, ?ystein; S?reide, Janne E.; Graeve, Martin; Berge, J?rgen; Falk-Petersen, Stig

    2010-01-01

    We present an accurate, fast, simple and non-destructive photographic method to estimate wax ester and lipid content in single individuals of the calanoid copepod genus Calanus and test this method against gas-chromatographic lipid measurements.

  16. VALIDASI MODIFIKASI METODE WEIßHAAR UNTUK ANALISIS 3-MCPD ESTER DALAM MINYAK GORENG SAWIT [Validation of Modified Weißhaar’s Method for 3-MCPD Esters Analysis in Palm Oil

    Directory of Open Access Journals (Sweden)

    Tanti Lanovia1,2*

    2014-12-01

    Full Text Available The 3-monochloropropane-1,2-diol (3-MCPD and 3-MCPD esters were found in any type of refined vegetable oil -mostly produced during the refining process- and recognized as emerging food contaminants. Several analytical methods have been developed and one of which was a Weißhaar's method. The study aims to validate the modified Weißhaar's method for analysis of 3-MCPD and 3-MCPD esters in refined palm oil. Ion fragments were used for identification and quantification of 3-MCPD and 3-MCPD-d5. 3-MCPD was determined by GC-MS after released from its ester by transesterification with sodium methoxide and derivatized with phenylboronic acid. The validation showed that liniarity response (r=0.994 was observed from a linear regression by using external standard and internal standard at a concentration range of 0.008 and 0.377 µg mL-1. The LOD of the validated method was 0.06 µg g-1 while its LOQ was 0.20 µg g-1, precision (relative standard deviation, RSD was 6.16%, and accuracy (as percentage of recovery was in the range of 95.83-113.27%. This results indicated that the modified method was valuable and sensitive for detection of 3-MCPD and 3-MCPD esters. Using the validated method, 3-MCPD esters content of a commercial palm oil sample was determined and calculated as the difference between total 3-MCPD and free 3-MCPD, which was 13.24 µg g-1. Total 3-MCPD content of several palm oils were at a concentration range of 13.94-34.52 µg g-1. These results also showed that there was a correlation between 3-MCPD with diacylglyceride (DAG. Samples with DAG content gave a high test results of 3-MCPD with a coefficient of correlation of r=0.752.

  17. Determination of Phthalate Esters in the Aquatic Environment ...

    African Journals Online (AJOL)

    The use of solid phase extraction and capillary GLC provides the basis for selective determination of phthalate ester plasticizers in rivers and marine water samples. Of the several solvent ratios (methanol in dichloromethane) that were tried for selective elution of phthalate esters from the C18 solid phase glass catridge, the ...

  18. Effect of Sucrose Esters on the Physicochemical Properties of Wheat ...

    African Journals Online (AJOL)

    HP

    Purpose: To investigate the effect of sucrose esters on the physicochemical properties of wheat starch. Methods: Sucrose ester was mixed with wheat starch extracted from normal soft wheat cultivars and heated. Change in starch properties arising from the interaction between were assessed for starch blue value, viscosity ...

  19. Alternative Production of Fatty Acid Methyl Esters from Triglycerides ...

    African Journals Online (AJOL)

    The catalysts activity was tested in thermocatalytic cracking of triglyceride; a direct conversion process for fatty acid methyl esters (biodiesel). The SZ1 not only exhibited higher conversion of triglycerides but higher fatty acid methyl esters (FAMEs) yields of approximately 59% after 3h as compared to SZ2 (32%). In addition ...

  20. 13-week oral toxicity study with stanol esters in rats

    NARCIS (Netherlands)

    Turnbull, D.; Whittaker, M.H.; Frankos, V.H.; Jonker, D.

    1999-01-01

    Plant sterols and their saturated derivatives, known as stanols, reduce serum cholesterol when consumed in amounts of approximately 2 g per day. Stanol fatty acid esters have been developed as a highly fat-soluble form that may lower cholesterol more effectively than stanols. Stanol esters occur

  1. Preparation of esters of gallic acid with higher primary alcohols

    NARCIS (Netherlands)

    Kerk, G.J.M. van der; Verbeek, J.H.; Cleton, J.C.F.

    1951-01-01

    The esters of gallic acid and higher primary alcohols, especially fatty alcohols, have recently gained considerable interest as possible antioxidants for fats. Two independent methods for the preparation of these esters are described. In the first method the hitherto unknown compound galloyl

  2. Distribution of phthalate esters in underground water from power ...

    African Journals Online (AJOL)

    This study investigates the distribution of phthalateacid esters (PAEs) in groundwater from some power stations in Delta State. Groundwater samples were collected from eight power transmission and distribution stations. Concentrations (μg/L) of six phthalate acid esters compounds in the groundwater ranged from ...

  3. SYNTHESIS OF FATTY ACID ETHYL ESTER FROM CHICKEN FAT ...

    African Journals Online (AJOL)

    eobe

    synthesis of fatty acid ethyl ester from chicken fat waste using ZnO/SiO fatty acid ethyl ester ... obtained in the range of 56−88%and a second order quadratic polynomial regression model that established the ... Transesterification is a chemical.

  4. Experimental assessment of toxic phorbol ester in oil, biodiesel and seed cake of Jatropha curcas and use of biodiesel in diesel engine

    International Nuclear Information System (INIS)

    Prasad, Lalit; Pradhan, Subhalaxmi; Das, L.M.; Naik, S.N.

    2012-01-01

    Highlights: ► In the present study toxic phorbol esters were detected in oil and seed cake of Jatropha curcas but not detected in biodiesel using high performance liquid chromatography (HPLC). ► The quantity of phorbol esters in Jatropha curcas oil and cake were amounted to be 2.12 ± 0.02 mg/g and 0.6 ± 0.01 mg/g respectively. ► As jatropha oil is a potential source for biodiesel preparation, huge amount of oil and cake will be generated and hence need to be handled carefully. ► Upon engine study exhaust pollutant such as hydrocarbon, smoke opacity and carbon monoxide reduced substantially. - Abstract: The present study deals with estimation of toxic phorbol esters in Jatropha curcas oil, cake and biodiesel and performance emission of different blends of biodiesel in diesel engine. The jatropha seed was collected from Chattishgarh, India and oil content of the seed kernel was 56.5%, determined by soxhlet apparatus. The oil was subjected to biodiesel preparation by twin step method of acid esterification followed by alkali transesterification. The total conversion of jatropha oil methyl ester (JOME) after reaction was 96.05% from proton nuclear magnetic resonance ( 1 H NMR) studies. The phorbol esters content of oil, cake and biodiesel was determined by high performance liquid chromatography (HPLC, Waters). The phorbol esters content of the oil was more (2.26 ± 0.01 mg/g) than the cake (0.6 ± 0.01 mg/g) but no phorbol esters peak was detected in biodiesel. The performance and emission study of the fuel blends (JB2, JB5 and JB10) with conventional diesel were tested for their use as substitute fuel for a single cylinder direct injection diesel engine at constant speed (1500 rpm). The emissions such as CO, HC and smoke opacity decreased whereas NO x and BSCF increased with biodiesel blends.

  5. Discrimination of processing grades of olive oil and other vegetable oils by monochloropropanediol esters and glycidyl esters

    NARCIS (Netherlands)

    Yan, Jing; Oey, Sergio B.; Leeuwen, van Stefan P.J.; Ruth, van Saskia M.

    2018-01-01

    In this study, the processing derived contaminants 2- and 3-monochloropropanediol (2- and 3-MCPD) esters and glycidyl esters (GEs) were analysed in 84 oil samples by GC–MS/MS for the discrimination of processing grades of olive oils as a potential authentication tool. Concentrations of 2- and 3-MCPD

  6. pH-triggered chitosan nanogels via an ortho ester-based linkage for efficient chemotherapy.

    Science.gov (United States)

    Yang, Guanqing; Wang, Xin; Fu, Shengxiang; Tang, Rupei; Wang, Jun

    2017-09-15

    We report on new types of chitosan-based nanogels via an ortho ester-based linkage, used as drug carriers for efficient chemotherapy. First, we synthesized a novel diacrylamide containing ortho ester (OEAM) as an acid-labile cross-linker. Subsequently, methacrylated succinyl-chitosan (MASCS) was prepared and polymerized with OEAM at different molar ratios to give a series of pH-triggered MASCS nanogels. Doxorubicin (DOX) as a model anticancer drug was loaded into MASCS nanogels with a loading content of 16.5%. As expected, with the incorporation of ortho ester linkages, these nanogels showed pH-triggered degradation and drug release at acidic pH values. In vitro cellular uptake shows that the DOX-loaded nanogels could be preferentially internalized by two-dimensional (2D) cells and three-dimensional (3D) multicellular spheroids (MCs), resulting in higher inhibition of the proliferation of tumor cells. In vivo biodistribution and anti-tumor effect were determined in H22 tumor-bearing mice, and the results demonstrate that the acid-labile MASCS nanogels can significantly prolong the blood circulation time of DOX and improve the accumulation in tumor areas, leading to higher therapeutic efficacy. We designed new pH-triggered chitosan nanogels via an ortho ester-based cross-linker for efficient drug-loading and chemotherapy. These drug-loaded nanogels exhibit excellent pH-triggered drug release behavior due to the degradation of ortho ester linkages in mildly acidic environments. In vitro and in vivo results demonstrate that the nanogels could be efficiently internalized by 2D cells and 3D-MCs, improve drug concentration in solid tumors, and lead to higher therapeutic efficacy. To the best of our knowledge, this is the first report on using an ortho ester-based cross-linker to prepare pH-triggered chitosan nanogels as tumor carriers, which may provide a potential route for improved safety and to increase the therapeutic efficacy of anticancer therapy. Copyright © 2017

  7. Use of citric acid esters as alternative fuel for diesel engines

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Georg; Thuneke, Klaus; Remmele, Edgar [Technologie- und Foerderzentrum, Straubing (Germany); Schieder, Doris [Technische Univ. Muenchen, Straubing (Germany). Lehrstuhl fuer Chemie Biogener Rohstoffe

    2013-06-01

    Common fuels for (adapted) diesel engines are fossil diesel fuel, fatty acid methyl ester (FAME or biodiesel) or vegetable oils. Furthermore the citric acid esters tributylcitrate (TBC) and triethylcitrate (TEC) are expected to be a possible diesel substitute. Their use as fuel was applied for a patent in Germany in 2010. According to the patent applicant the advantages are low soot combustion, independence of energy imports due to the possibility of local production and a broad raw material base. Their fuel properties have been analysed in the laboratory and compared with the relevant fuel standards. Only some of the determined values are meeting the specifications, but on the other hand few rapeseed oil characteristics (e. g. oxidation stability and viscosity) can be improved if the citric acid esters are used as a blend component. The operating and emission behaviour of a vegetable oil compatible CHP unit fuelled with various rapeseed oil and TBC blends were investigated and a trouble free and soot emission reduced engine operation due to the high molecularly bound oxygen content was observed. Long term test runs are necessary for an entire technical validation. (orig.)

  8. Chromatographic analyses of fatty acid methyl esters by HPLC-UV and GC-FID

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Myller S.; Pinho, David M.M.; Suarez, Paulo A.Z., E-mail: psuarez@unb.br [Laboratorio de Materiais e Combustiveis, Instituto de Quimica, Universidade de Brasilia, DF (Brazil); Mendonca, Marcio A. [Faculdade de Agronomia e Medicina Veterinaria, Universidade de Brasilia, DF (Brazil); Resck, Ines S. [Laboratorio de Ressonancia Magnetica Nuclear, Universidade de Brasilia, DF (Brazil)

    2012-04-15

    An analytical method using high performance liquid chromatography with UV detection (HPLC-UV) (method A) was used for simultaneous determination of total amounts of triacylglycerides, diacylglycerides, monoacylglycerides and fatty acid methyl esters in alcoholysis of different oil (cotton, canola, sunflower, corn and soybean) samples. Analyses were carried out at 40 deg C for 20 min using a gradient of methanol (MeOH) and 2-propanol-hexane 5:4 (v/v) (PrHex): 100% of MeOH in 0 min, 50% of MeOH and 50% of PrHex in 10 min maintained with isocratic elution for 10 min. Another HPLC-UV method (method B) with acetonitrile isocratic elution for 34 min was used to determine the fatty acid composition of oils analyzing their methyl ester derivatives. Contents were determined with satisfactory repeatability (relative standard deviation, RSD < 3%), linearity (r{sup 2} > 0.99) and sensitivity (limit of quantification). Method B was compared with an official gas chromatographic method with flame ionization detection (GC-FID) from American Oil Chemists' Society (AOCS) in the determination of fatty acid methyl esters (FAME) in biodiesel real samples. (author)

  9. Study on the spray characteristics of methyl esters from waste cooking oil at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yung-Sung [Department of Mechanical and Automation Engineering, Da-Yeh University, 168 University Road, Dacun, Changhua 51591 (China); Department of Mechanical Engineering, Hsiuping Institute of Technology, No.11, Gongye Rd., Dali City, Taichung County 412-80 (China); Lin, Hai-Ping [Department of Mechanical and Automation Engineering, Da-Yeh University, 168 University Road, Dacun, Changhua 51591 (China)

    2010-09-15

    In Taiwan, millions of tons of waste cooking oil are produced each year, and less than 20% of it, about 150,000 ton/a, is reclaimed and reused. Most waste oil is flushed down the drain. Utilizing waste cooking oil to make biodiesel not only reduces engine exhaust gas pollution, but also replaces food-derived fuels, and reduces ecologic river pollution. This study employed two-stage transesterification to lower the high viscosity of waste oil, utilized emulsion to reduce the methyl ester NOx pollution, and used methanol to enhance the stability and viscosity of emulsified fuel. To further analyze spray characteristics of fuels, this experiment built a constant volume bomb under high temperature, used high speed photography to analyze spray tip penetration, spray angle, and the Sauter mean diameter (SMD) of fuel droplets, and compared the results with fossil diesel. The experimental results suggested that, two-stage transesterification can significantly lower waste oil viscosity to that which is close to fossil diesel viscosity. At a temperature above 300 C, waste cooking oil methyl esters had a water content of 20%, spray droplet characteristics were significantly improved, and NOx emission dropped significantly. The optimal fuel ratio suggested in this experiment was waste cooking oil methyl ester 74.5%, methanol 5%, water 20%, and composite surfactant Span-Tween 0.5%. (author)

  10. A Ketone Ester Drink Increases Postexercise Muscle Glycogen Synthesis in Humans.

    Science.gov (United States)

    Holdsworth, David A; Cox, Peter J; Kirk, Tom; Stradling, Huw; Impey, Samuel G; Clarke, Kieran

    2017-09-01

    Physical endurance can be limited by muscle glycogen stores, in that glycogen depletion markedly reduces external work. During carbohydrate restriction, the liver synthesizes the ketone bodies, D-β-hydroxybutyrate, and acetoacetate from fatty acids. In animals and in the presence of glucose, D-β-hydroxybutyrate promotes insulin secretion and increases glycogen synthesis. Here we determined whether a dietary ketone ester, combined with plentiful glucose, can increase postexercise glycogen synthesis in human skeletal muscle. After an interval-based glycogen depletion exercise protocol, 12 well-trained male athletes completed a randomized, three-arm, blinded crossover recovery study that consisted of consumption of either a taste-matched, zero-calorie control or a ketone monoester drink, followed by a 10-mM glucose clamp or saline infusion for 2 h. The three postexercise conditions were control drink then saline infusion, control drink then hyperglycemic clamp, or ketone ester drink then hyperglycemic clamp. Skeletal muscle glycogen content was determined in muscle biopsies of vastus lateralis taken before and after the 2-h clamps. The ketone ester drink increased blood D-β-hydroxybutyrate concentrations to a maximum of 5.3 versus 0.7 mM for the control drink (P glycogen was 50% higher (246 vs 164 mmol glycosyl units per kilogram dry weight, P glycogen synthesis.

  11. In vivo transfer of cholesteryl ester from high and low density plasma lipoproteins into human aortic tissue

    International Nuclear Information System (INIS)

    Stender, S.; Hjelms, E.

    1988-01-01

    For the study of cholesteryl ester transfer from different plasma lipoproteins into human aortic tissue, patients scheduled for reconstructive aortic surgery were intravenously injected with autologous in vitro labeled lipoproteins 20 to 24 hours before aortic intima-media samples were obtained during the operation. The injectate contained high density lipoproteins (d greater than 1.063) labeled with 3H-cholesteryl ester and lipoproteins of lower density (d less than 1.063) labeled with 14C-cholesteryl ester or lipoproteins with the opposite labeling. In 16 aortic tissue samples (some with visible atherosclerosis) from 11 normocholesterolemic patients, the aortic influx of total cholesteryl ester was 1 to 50 nmol x cm-2 x day-1. Some 39% +/- 3% (mean +/- SEM) of the influx was derived from high density lipoproteins, which in plasma accounted for only 22% +/- 2% (mean +/- SEM) of the esterified cholesterol. The findings suggest that: 1) esterified cholesterol from the two lipoprotein fractions in plasma enter the aortic intima by the same mechanism, and 2) influx of cholesteryl ester from the smaller, high density lipoproteins is greater than influx from the larger, lower density lipoproteins considering their concentrations in plasma. In some patients, the cholesterol content in the intima-media tissue with no visible atherosclerosis corresponded to only a few months of continuous cholesteryl ester influx. This time is short considering the age of the patients and, therefore, indicates that removal of esterified cholesterol from the intima-media is of major importance in preventing cholesterol deposition in the arterial wall

  12. Stability of a metabolizable ester bond in radioimmunoconjugates

    International Nuclear Information System (INIS)

    Arano, Yasushi; Wakisaka, Kouji; Mukai, Takahiro; Uezono, Takashi; Motonari, Hiroshi; Akizawa, Hiromichi; Kairiyama, Claudia; Ohmomo, Yoshiro; Tanaka, Chiaki; Ishiyama, Munetaka; Sakahara, Harumi; Konishi, Junji; Yokoyama, Akira

    1996-01-01

    Ester bonds have been used as metabolizable linkages to reduce radioactivity levels in non-target tissues following the administration of antibodies labeled with metallic radionuclides. In this radiochemical design of antibodies, while the ester bonds should be cleaved rapidly in non-target tissues, high stability of the ester bonds in plasma is also required to preserve target radioactivity levels. To assess the structural requirements to stabilize the ester bond, a new benzyl-EDTA-derived bifunctional chelating agent with an ester bond, (1-[4-[4-(2-maleimidoethoxy)succinamido]benzyl]ethylenediamine-N,N,N',N'- tetraacetic acid; MESS-Bz-EDTA), was developed. MESS-Bz-EDTA was coupled with a thiolated monoclonal antibody (OST7, IgG 1 ) prepared by reducing its disulfide bonds to introduce the ester bond close and proximal to the antibody molecule. For comparison, 1-[4-(5-maleimidopentyl)aminobenzyl]ethylenediamine-N,N,N',N'-tetraacetic acid (EMCS-Bz-EDTA) and meleimidoethyl 3-[ 131 I]iodohippurate (MIH) was coupled to OST7 under the same conjunction chemistry. When incubated in 50% murine plasma or a buffered-solution of neutral pH, OST7-MESS-Bz-EDTA- 111 In rapidly released the radioactivity, and more than 95% of the initial radioactivity was liberated after a 24 h incubation in both solutions, due to a cleavage of the ester bond. On the other hand, only about 20% of the radioactivity was released from OST7-MIH- 131 I in both solutions during the same incubation period. In mice biodistribution studies, while a slightly faster radioactivity clearance from the blood with less radioactivity levels in the liver and kidneys was observed with OST7-MIH- 131 I than with OST7-EMCS-Bz-EDTA- 111 In, OST7-MESS-Bz-EDTA- 111 In indicated radioactivity clearance from the blood much faster than and almost comparable to that of OST7-MIH- 131 I and succinamidobenzyl-EDTA- 111 In, respectively. These findings as well as previous findings on radiolabeled antibodies with ester bonds

  13. Engineering low phorbol ester Jatropha curcas seed by intercepting casbene biosynthesis.

    Science.gov (United States)

    Li, Chunhong; Ng, Ailing; Xie, Lifen; Mao, Huizhu; Qiu, Chengxiang; Srinivasan, Ramachandran; Yin, Zhongchao; Hong, Yan

    2016-01-01

    Casbene is a precursor to phorbol esters and down-regulating casbene synthase effectively reduces phorbol ester biosynthesis. Seed-specific reduction of phorbol ester (PE) helps develop Jatropha seed cake for animal nutrition. Phorbol esters (PEs) are diterpenoids present in some Euphorbiaceae family members like Jatropha curcas L. (Jatropha), a tropical shrub yielding high-quality oil suitable as feedstock for biodiesel and bio jet fuel. Jatropha seed contains up to 40 % of oil and can produce oil together with cake containing high-quality proteins. However, skin-irritating and cancer-promoting PEs make Jatropha cake meal unsuitable for animal nutrition and also raise some safety and environmental concerns on its planting and processing. Two casbene synthase gene (JcCASA163 and JcCASD168) homologues were cloned from Jatropha genome and both genes were highly expressed during seed development. In vitro functional analysis proved casbene synthase activity of JcCASA163 in converting geranylgeranyl diphosphate into casbene which has been speculated to be the precursor to PEs. A seed-specific promoter driving inverted repeats for RNAi interference targeting at either JcCASA163 or both genes could effectively down-regulate casbene synthase gene expression with concurrent marked reduction of PE level (by as much as 85 %) in seeds with no pleiotropic effects observed. Such engineered low PE in seed was heritable and co-segregated with the transgene. Our work implicated casbene synthase in Jatropha PE biosynthesis and provided evidence for casbene being the precursor for PEs. The success in reducing seed PE content through down-regulation of casbene synthase demonstrates the feasibility of intercepting PE biosynthesis in Jatropha seed to help address safety concerns on Jatropha plantation and seed processing and facilitate use of its seed protein for animal nutrition.

  14. Esters of ricebran oil with short chain alcohols as alternative fuel for diesel engines

    Directory of Open Access Journals (Sweden)

    F.A. Zaher

    2016-06-01

    Full Text Available The potential of ricebran oil as a feedstock for the production of a fuel for diesel engines alternative to regular diesel fuel has been assessed. Esterification rate of crude ricebran oil with methyl alcohol was studied using different volumetric ratios of alcohol to oil, different catalyst loads and catalyst types. Catalysts used were sulfuric acid at a concentration of 2% of the oil/alcohol mixture in addition to hydrochloric acid and Amberlite IR-120 cation exchange resin at the same molar concentration of H+ as in case of sulfuric acid. The reaction was fastest using sulfuric acid which has been then used to prepare esters of ricebran oil with methyl, ethyl, propyl and butyl alcohols. The four products have been evaluated as a fuel for diesel engines according to their fuel properties compared to regular diesel fuel. These properties include the calorific value, flash point, viscosity, pour point, cetane number, sulfur content and ASTM distillation characteristics. The results have shown that the methyl as well as the ethyl esters have the closest properties to those of regular diesel fuel. Diesel engine performance using blends of regular diesel fuel with methyl and ethyl esters of ricebran oil have been tested and compared to that using regular diesel fuel. The results have shown that the engine performance using a blend of 50% regular diesel fuel and 50% methyl esters of ricebran oil is better than that using regular diesel fuel. The brake thermal efficiency at full load was 30.2% using the fuel blend compared to 27.5% in case of regular fuel.

  15. List of Article Contents

    Directory of Open Access Journals (Sweden)

    Editorial Section

    2014-12-01

    Full Text Available CONTENTS OF ARTICLES Premixed combustion of coconut oil in a hele-shaw cell DOI: 10.14710/ijred.3.3.155-160 155-160 Hadi Saroso, I.N.G. Wardana, Rudy Soenoko, Nurkholis Hamidi   Analysing the potential of retrofitting ultra-low heat loss triple vacuum glazed windows to an existing UK solid wall dwelling DOI: 10.14710/ijred.3.3.161-174 161-174 Saim Memon   Study of Gasohol as Alternative Fuel for Gasoline Substitution: Characteristics and Performances DOI: 10.14710/ijred.3.3.175-183 175-183 Bardi Murachman, Dicky Pranantyo, Eddie Sandjaya Putra   Thermal effects investigation on electrical properties of silicon solar cells treated by laser irradiation DOI: 10.14710/ijred.3.3.184-187 184-187 Ali Pourakbar Saffar, Bahman Deldadeh Barani   Synthesis of Trimethylolpropane Esters of Calophyllum Methyl Esters : Effect of Temperatur and Molar Ratio DOI: 10.14710/ijred.3.3.188-192 188-192 Yeti Widyawati, Ani Suryani, Muhammad Romli, Sukardi Sukardi   Incorporating Root Crops under Agro-Forestry as the Newly Potential Source of Food, Feed and Renewable Energy DOI: 10.14710/ijred.3.3.193-206 193-206 Yudi Widodo, St. A. Rahayuningsih, Nasir Saleh, Sri Wahyuningsih   Solmap: Project In India's Solar Resource Assessment DOI: 10.14710/ijred.3.3.207-216 207-216 Indradip Mitra, Kaushal Chhatbar, Ashvini Kumar, Godugunur Giridhar, Ramdhan Vashistha, Richard Meyer, Marko Schwandt   Thermo-economic Optimization of Solar Assisted Heating and Cooling (SAHC System DOI: 10.14710/ijred.3.3.217-227 217-227 A. Ghafoor, A. Munir   Combustion characteristics of diesel engine using producer gas and blends of Jatropha methyl ester with diesel in mixed fuel mode DOI: 10.14710/ijred.3.3.228-235 228-235 Hifjur Raheman, Debasish Padhee    

  16. Thermal and mechanical properties of fatty acid starch esters.

    Science.gov (United States)

    Winkler, H; Vorwerg, W; Rihm, R

    2014-02-15

    The current study examined thermal and mechanical properties of fatty acid starch esters (FASEs). All highly soluble esters were obtained by the sustainable, homogeneous transesterification of fatty acid vinyl esters in dimethylsulfoxide (DMSO). Casted films of products with a degree of substitution (DS) of 1.40-1.73 were compared with highly substituted ones (DS 2.20-2.63). All films were free of any plasticizer additives. Hydrophobic surfaces were characterized by contact angle measurements. Dynamic scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) revealed thermal transitions (T(g), T(m)) which were influenced by the internal plasticizing effect of the ester groups. Thermal gravimetric analysis (TGA) measurements showed the increased thermal stability toward native starch. Tensile tests revealed the decreasing strength and stiffness of the products with increasing ester-group chain length while the elongation increased up to the ester group laurate and after that decreased. Esters of the longest fatty acids, palmitate and stearate turned out to be brittle materials due to super molecular structures of the ester chains such as confirmed by X-ray. Summarized products with a DS 1.40-1.73 featured more "starch-like" properties with tensile strength up to outstanding 43 MPa, while products with a DS >2 behaved more "oil-like". Both classes of esters should be tested as a serious alternative to commercial starch blends and petrol-based plastics. The term Cnumber is attributed to the number of total C-Atoms of the fatty acid (e.g. C6=Hexanoate). Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Fuel properties of biodiesel from vegetable oils and oil mixtures. Influence of methyl esters distribution

    International Nuclear Information System (INIS)

    Martínez, G.; Sánchez, N.; Encinar, J.M.; González, J.F.

    2014-01-01

    In this work, the quality of biodiesel produced by basic transesterification from several vegetable oils (soybean, rapeseed, sunflower, high oleic sunflower, Cynara Cardunculus L., Brassica Carinata and Jatropha Curca) cultivated in Extremadura has been studied in detail. The influence of raw material composition on properties such as density, viscosity, cetane number, higher heating value, iodine and saponification values and cold filter plugging point has been verified. Other biodiesel properties such as acid value, water content and flash and combustion points were more dependent on characteristics of production process. Biodiesel produced by rapeseed, sunflower and high oleic sunflower oils transesterification have been biofuels with better properties according to Norm EN 14214. Finally, it has been tested that it is possible to use oils mixtures in biodiesel production in order to improve the biodiesel quality. In addition, with the same process conditions and knowing properties of biodiesel from pure oils; for biodiesel from oils mixtures, its methyl esters content, and therefore properties dependent this content can be predicted from a simple mathematical equation proposed in this work. - Highlights: • Biodiesel quality produced by basic transesterification from vegetable oils. • We examine influences of methyl esters distribution on biodiesel properties. • Biofuels from soybean, sunflower and rapeseed oils were with better properties. • Oils mixtures improve biodiesel quality to fulfill Norm EN 14214. • An equation to predict properties of biodiesel from oil mixtures is proposed

  18. Sugar ester surfactants: enzymatic synthesis and applications in food industry.

    Science.gov (United States)

    Neta, Nair S; Teixeira, José A; Rodrigues, Lígia R

    2015-01-01

    Sugar esters are non-ionic surfactants that can be synthesized in a single enzymatic reaction step using lipases. The stability and efficiency of lipases under unusual conditions and using non-conventional media can be significantly improved through immobilization and protein engineering. Also, the development of de novo enzymes has seen a significant increase lately under the scope of the new field of synthetic biology. Depending on the esterification degree and the nature of fatty acid and/or sugar, a range of sugar esters can be synthesized. Due to their surface activity and emulsifying capacity, sugar esters are promising for applications in food industry.

  19. Catalytic Oxidation of Allylic Alcohols to Methyl Esters

    DEFF Research Database (Denmark)

    Gallas-Hulin, Agata; Kotni, Rama Krishna; Nielsen, Martin

    2017-01-01

    Aerobic oxidation of allylic alcohols to methyl esters using gold nanoparticles supported on different metal oxide carriers has been performed successfully under mild conditions (room temperature, 0.1 MPa O2) without significant loss of catalytic activity. The effects of different reaction...... parameters are studied to find the suitable reaction conditions. All catalysts are characterised by XRD, XRF and TEM. Among these catalysts, Au/TiO2 showed the most efficient catalytic activity towards the selective oxidation of allylic alcohols to the corresponding esters. Moreover, the same Au/TiO2...... to synthesize methyl esters from allylic alcohols....

  20. Solvent-Free Lipase-Catalyzed Synthesis of Technical-Grade Sugar Esters and Evaluation of Their Physicochemical and Bioactive Properties

    Directory of Open Access Journals (Sweden)

    Ran Ye

    2016-05-01

    Full Text Available Technical-grade oleic acid esters of sucrose and fructose were prepared using solvent-free biocatalysis at 65 °C, without any downstream purification applied, and their physicochemical and bioactivity-related properties were evaluated and compared to a commercially available sucrose laurate emulsifier. To increase the conversion of sucrose and fructose oleate, prepared previously using solvent-free lipase-catalyzed esterification catalyzed by Rhizomucor miehei lipase (81% and 83% ester, respectively, the enzymatic reaction conditions was continued using CaSO4 to control the reactor’s air headspace and a lipase (from Candida antarctica B with a hydrophobic immobilization matrix to provide an ultralow water activity, and high-pressure homogenation, to form metastable suspensions of 2.0–3.3 micron sized saccharide particles in liquid-phase reaction media. These measures led to increased ester content of 89% and 96% for reactions involving sucrose and fructose, respectively. The monoester content among the esters decreased from 90% to <70% due to differences in regioselectivity between the lipases. The resultant technical-grade sucrose and fructose lowered the surface tension to <30 mN/m, and possessed excellent emulsification capability and stability over 36 h using hexadecane and dodecane as oils, comparable to that of sucrose laurate and Tween® 80. The technical-grade sugar esters, particularly fructose oleate, more effectively inhibited gram-positive foodborne pathogens (Lactobacillus plantarum, Pediococcus pentosaceus and Bacillus subtilis. Furthermore, all three sugar esters displayed antitumor activity, particularly the two sucrose esters. This study demonstrates the importance of controlling the biocatalysts’ water activity to achieve high conversion, the impact of a lipase’s regioselectivity in dictating product distribution, and the use of solvent-free biocatalysis to important biobased surfactants useful in foods, cosmetics

  1. Effects of temperature and NaCl on the formation of 3-MCPD esters and glycidyl esters in refined, bleached and deodorized palm olein during deep-fat frying of potato chips.

    Science.gov (United States)

    Wong, Yu Hua; Muhamad, Halimah; Abas, Faridah; Lai, Oi Ming; Nyam, Kar Lin; Tan, Chin Ping

    2017-03-15

    The effects of frying duration, frying temperature and concentration of sodium chloride on the formation of 3-monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters (GEs) of refined, bleached and deodorized (RBD) palm olein during deep-fat frying (at 160°C and 180°C) of potato chips (0%, 1%, 3% and 5% NaCl) for 100min/d for five consecutive days in eight systems were compared in this study. All oil samples collected after each frying cycle were analyzed for 3-MCPD esters, GEs, free fatty acid (FFA) contents, specific extinction at 232 and 268 nm (K 232 and K 268 ), p-anisidine value (pAV), and fatty acid composition. The 3-MCPD ester trend was decreasing when the frying duration increased, whereas the trend was increasing when frying temperature and concentration of NaCl increased. The GEs trend was increasing when the frying temperature, frying duration and concentration of NaCl increased. All of the oil qualities were within the safety limit. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. 21 CFR 172.852 - Glyceryl-lacto esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Glyceryl-lacto esters of fatty acids. 172.852... HUMAN CONSUMPTION Multipurpose Additives § 172.852 Glyceryl-lacto esters of fatty acids. Glyceryl-lacto esters of fatty acids (the lactic acid esters of mono- and diglycerides) may be safely used in food in...

  3. Complex formation of technetium with the methyl esters of MAG2 and MAG1

    International Nuclear Information System (INIS)

    Noll, B.; Noll, S.; Grosse, B.; Johannsen, B.; Spies, H.

    1993-01-01

    Mercaptoacetylglycine methyl ester (MAG 2 ester) and mercaptoacetyldiglycine methyl ester (MAG 1 ester) were included to investigate complex formation of SH/amide ligands with technetium. The studies are aimed at finding out how blocking the carboxylic groups influences the complexation reaction, with a view to finding an approach to new lipophilic species. (orig./BBR)

  4. Synthesis and Characterization of Fatty Acid Methyl Ester by In-Situ Transesterification in Capparis Deciduas Seed

    Directory of Open Access Journals (Sweden)

    Prasad E FUNDE

    2008-12-01

    Full Text Available (FAME Fatty acid methyl ester is made virgin or used vegetable oils (both edible and non-edible and animal fats. Fatty acid methyl ester operates in compression ignition engines like petro-diesel. Fatty acid methyl ester can be blended in any ratio with petroleum diesel fuels. It can be stored just like the petroleum diesel fuel. Petrodiesel can be replaced by biodiesel due to its superiority. It has various advantages. The seeds of Capparis deciduas are found to contain non-edible oil in the range of about 63.75 %. The percentage of biodiesel yield increases with concentration of KOH as a catalyst. The aim of this article is to demonstrate the cost effective new source of energy by single step reaction i.e. production of oil by combining extraction and reaction of extract with the mixture of alcohols. In this article the effect of catalyst concentration, time, water content and temperature on in-situ transesterification is studied to obtain optimum yield and Fatty acid methyl ester (Biodiesel Fuel characterization tests show the striking similarity of various physical & chemical properties and campers to ASTM standards.

  5. Experimental studies on natural aspirated diesel engine fuelled with corn seed oil methyl ester as a bio-diesel.

    Science.gov (United States)

    Rama Krishna Reddy, E.; Dhana Raju, V.

    2018-03-01

    This paper evaluates the possibilities of using corn seed oil methyl ester as a fuel for compression ignition engines. The biodiesels are contained high oxygen content, and high Cetane number, due to this properties efficiency of biodiesel is higher than diesel fuel. The experiments were conducted with different biodiesel blends of (B10, B15, B20 and B25) corn seed oil on single cylinder four stroke natural aspirated diesel engines. Performance parameters and exhaust emissions are investigated in this experimental with the blends of the corn seed oil methyl ester and diesel fuel. The test results showed that the bio-diesel blends gives improved results for brake thermal efficiency and specific fuel consumption when compared with the diesel fuel. The emissions of corn seed methyl esters follow the same trend of diesel but the smoke opacity was reduces for all blends. From the investigation, corn seed methyl ester is also having the properties similar to diesel fuel; it is biodegradable and renewable fuel, so it will be used as an alternative for diesel fuel.

  6. Formation of Plant Sterol Oxidation Products in Foods during Baking and Cooking Using Margarine without and with Added Plant Sterol Esters

    NARCIS (Netherlands)

    Lin, Y.; Knol, D.; Menéndez-Carreño, M.; Blom, W.A.M.; Matthee, J.; Janssen, H.G.; Trautwein, E.A.

    2016-01-01

    Plant sterols (PS) in foods are subject to thermal oxidation to form PS oxidation products (POP). This study measured POP contents of 19 foods prepared by typical household baking and cooking methods using margarines without (control) and with 7.5% added PS (as 12.5% PS-esters, PS-margarine). Median

  7. Hydrolytic Stability of Boronate Ester-Linked Covalent Organic Frameworks

    KAUST Repository

    Li, Huifang; Li, Haoyuan; Dai, Qingqing; Li, Hong; Bredas, Jean-Luc

    2018-01-01

    by reducing the energy barrier by a factor of 3. Importantly, the hydrolysis of boronate ester bonds situated in a COF environment follows reaction pathways that are different and have increased energy barriers. These results point to an enhanced hydrolytic

  8. ESTER: a new approach in modelling severe accidents

    International Nuclear Information System (INIS)

    Shepherd, I.; Jones, A.; Schmidt, F.

    1993-01-01

    ESTER is a set of codes for calculating phenomena during severe accidents in thermal reactors. It makes use of software tools that allow the data to be defined as a tree-structured data base and this data to be stored and retrieved by the code modules. The tools include generalized input and output routines that are independent of the particular code being used. Severe accident research codes are in a continual state of development and the structure of ESTER is such that modifications can be introduced easily and safely. The ESTER framework also facilitates the coupling together of codes. A preliminary version of ESTER containing a complete set of tools and a limited number of applications has already been released. 9 refs., 5 figs

  9. Evaluation of the levels of phthalate ester plasticizers in surface ...

    African Journals Online (AJOL)

    Evaluation of the levels of phthalate ester plasticizers in surface water of Ethiope ... Gas chromatography (GC) coupled with mass spectrometer (MS) was used to ... with their common use in plastic materials and other industrial chemicals.

  10. Production of both esters and biogas from Mexican poppy

    African Journals Online (AJOL)

    AJL

    scale industries and agricultural farms. Key words: Transestrification, energy conservation, anaerobic digestion, methane, biogas, methyl ester. INTRODUCTION. For advancement of civilization and socioeconomic developmental progress, the world is dependent on various energy resources like petrochemicals, coal,.

  11. Baker's yeast: production of D- and L-3-hydroxy esters

    DEFF Research Database (Denmark)

    Dahl, Allan Carsten; Madsen, Jørgen Øgaard

    1998-01-01

    harvested while growing. In contrast, the stereoselectivity was shifted towards L-hydroxy esters when the oxo esters were added slowly to ordinary baker's yeast supplied with gluconolactone as co-substrate. The reduction rate with gluconolactone was increased by active aeration. Ethyl L-(S)-3......Baker's yeast grown under oxygen limited conditions and used in the reduction of 3-oxo esters results in a shift of the stereoselectivity of the yeast towards D-hydroxy esters as compared with ordinary baker's yeast. The highest degree of stereoselectivity was obtained with growing yeast or yeast......-hydroxybutanoate was afforded in >99% ee. Both enantiomers of ethyl 3-hydroxypentanoate, D-(R) in 96% ee and L-(S) in 93% ee, and of ethyl 4-chloro-3-hydroxybutanoate, D-(S) in 98% ee and L-(R) in 94% ee, were obtained. The results demonstrate that the stereoselectivity of baker's yeast can be controlled...

  12. α-Imino Esters in Organic Synthesis: Recent Advances.

    Science.gov (United States)

    Eftekhari-Sis, Bagher; Zirak, Maryam

    2017-06-28

    α-Imino esters are useful precursors for the synthesis of a variety of types of natural and unnatural α-amino acid derivatives, with a wide range of biological activities. Due to the adjacent ester group, α-imino esters are more reactive relative to other types of imines and undergo different kinds of reactions, including organometallics addition, metal catalyzed vinylation and alkynylation, aza-Henry, aza-Morita-Baylis-Hillman, imino-ene, Mannich-type, and cycloaddition reactions, as well as hydrogenation and reduction. This review discusses the mechanism, scope, and applications of the reactions of α-imino esters and related compounds in organic synthesis, covering the literature from the last 12 years.

  13. Effect of Sucrose Esters on the Physicochemical Properties of Wheat ...

    African Journals Online (AJOL)

    HP

    In addition, the structure and thermodynamic properties of the ... Journal Citation Reports/Science Edition, Directory of Open Access Journals ... functional differences between wheat starches ..... esters cosurfactant microemulsion systems for.

  14. METODE ESTIMASI PROPERTI KRITIS UAP-CAIR KOMPONEN MURNI ESTER

    Directory of Open Access Journals (Sweden)

    Dhoni Hartantoa

    2014-03-01

    Full Text Available Biodiesel become eco-friendly renewable energy resources which is consisted of monoalkyl ester or long chain fatty acid from plants or animal. Biodiesel has more advantage than petrodiesel. Property of pure compound such as critical properties are the important thing to determine chemical mixtures behavior and also as base of equation of state. Joback method can show good results in estimating critical properties of monoalkyl ester.

  15. Sulfur deactivation of fatty ester hydrogenolysis catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Brands, D.S.; U-A-Sai, G.; Poels, E.K.; Bliek, A. [Univ. of Amsterdam (Netherlands). Dept. of Chemical Engineering

    1999-08-15

    Trace organosulfur compounds present as natural impurities in oleochemical feedstocks may lead to activation of copper-containing catalysts applied for hydrogenolysis of esters toward fatty alcohols. In this paper, the sulfur deactivation of Cu/SiO{sub 2} and Cu/ZnO/SiO{sub 2} catalysts was studied in the liquid-phase hydrogenolysis of methyl palmitate. The rate of deactivation is fast and increases as a function of the sulfur-containing compound present: octadecanethiol {approx} dihexadecyl disulfide < benzyl isothiocyanate < methyl p-toluene sulfonate < dihexadecyl sulfide < dibenzothiophene. The rapid deactivation is caused by the fact that sulfur is quantitatively removed from the reaction mixture and because mainly surface sulfides are formed under hydrogenolysis conditions. The life time of a zinc-promoted catalyst is up to two times higher than that of the Cu/SiO{sub 2} catalyst, most likely due to zinc surface sulfide formation. The maximum sulfur coverage obtained after full catalyst deactivation with dibenzothiophene and dihexadecyl sulfide--the sulfur compounds that cause the fastest deactivation--may be as low as 0.07. This is due to the fact that decomposition of these compounds as well as the hydrogenolysis reaction itself proceeds on ensembles of copper atoms. Catalyst regeneration studies reveal that activity cannot be regained by reduction or combined oxidation/reduction treatments. XRD, TPR, and TPO results confirm that no distinct bulk copper or zinc sulfide or sulfate phases are present.

  16. Combustion characteristics of the mustard methyl esters

    International Nuclear Information System (INIS)

    Bannikov, M.G.; Vasilev, I.P.

    2011-01-01

    Mustard Methyl Esters (further bio diesel) and regular diesel fuel were tested in direct injection diesel engine. Analysis of experimental data was supported by an analysis of fuel injection and combustion characteristics. Engine fuelled with bio diesel had increased brake specific fuel consumption, reduced nitrogen oxides emission and smoke opacity, moderate increase in carbon monoxide emission with essentially unchanged unburned hydrocarbons emission. Increase in fuel consumption was attributed to lesser heating value of bio diesel and partially to decreased fuel conversion efficiency. Analysis of combustion characteristics revealed earlier start of injection and shorter ignition delay period of bio diesel. Resulting decrease in maximum rate of heat release and cylinder pressure was the most probable reason for reduced emission of nitrogen oxides. Analysis of combustion characteristics also showed that cetane index determined by ASTM Method D976 is not a proper measure of ignition quality of bio diesel. Conclusion was made on applicability of mustard oil as a source for commercial production of bio diesel in Pakistan. Potentialities of on improving combustion and emissions characteristics of diesel engine by reformulating bio diesel were discussed. (author)

  17. Lutein bioavailability from lutein ester-fortified fermented milk: in vivo and in vitro study.

    Science.gov (United States)

    Granado-Lorencio, Fernando; Herrero-Barbudo, Carmer; Olmedilla-Alonso, Begoña; Blanco-Navarro, Inmaculada; Pérez-Sacristán, Belén

    2010-02-01

    We assessed the bioavailability of lutein from lutein-fortified fermented milk using in vivo and in vitro approaches. Twenty-four volunteers were randomized to take lutein-fortified fermented milk at two levels of fortification. Single-dose bioavailability study (2x100 ml, ca. 8 or 16 mg of lutein) was performed using a three-point approach (baseline, 3.5 and 6.5 h). Multiple-dose study consisted of consuming one serving/day (ca. 4 or 8 mg/100 ml) for 14 days. Blood samples for biochemical, hematological and lutein analysis were drawn at baseline, Day 7 and Day 14. In vitro bioaccessibility was assessed by a static gastrointestinal digestion model. Lutein content, in vitro ester hydrolysis and micellarization, and lutein concentrations achieved in serum were analyzed by HPLC. In vivo, post-prandial response was higher using the high content fermented milk, but the percentage of absorption was not different according to the dose consumed. Net increments at Day 7 and Day 14 were significantly higher on consuming the high-dose milk as well. In vitro, lutein ester hydrolysis was incomplete regardless of the amount initially present. Free lutein released was higher using the high-dose fermented milk, but the percentage of hydrolysis was similar at both levels of fortification. In the micellar phase, the percentage of free and total lutein was not different according to the dose. Our results support the suitability of the fermented milk as a carrier of lutein esters and an in vivo dose-dependent effect upon regular consumption and suggest the usefulness of in vitro models to provide relevant information to predict in vivo responses. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Coriander seed oil methyl esters as biodiesel fuel: Unique fatty acid composition and excellent oxidative stability

    International Nuclear Information System (INIS)

    Moser, Bryan R.; Vaughn, Steven F.

    2010-01-01

    Coriander (Coriandrum sativum L.) seed oil methyl esters were prepared and evaluated as an alternative biodiesel fuel and contained an unusual fatty acid hitherto unreported as the principle component in biodiesel fuels: petroselinic (6Z-octadecenoic; 68.5 wt%) acid. Most of the remaining fatty acid profile consisted of common 18 carbon constituents such as linoleic (9Z,12Z-octadeca-dienoic; 13.0 wt%), oleic (9Z-octadecenoic; 7.6 wt%) and stearic (octadecanoic; 3.1 wt%) acids. A standard transesterification procedure with methanol and sodium methoxide catalyst was used to provide C. sativum oil methyl esters (CSME). Acid-catalyzed pretreatment was necessary beforehand to reduce the acid value of the oil from 2.66 to 0.47 mg g -1 . The derived cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of CSME was 53.3, 4.21 mm 2 s -1 (40 o C), and 14.6 h (110 o C). The cold filter plugging and pour points were -15 o C and -19 o C, respectively. Other properties such as acid value, free and total glycerol content, iodine value, as well as sulfur and phosphorous contents were acceptable according to the biodiesel standards ASTM D6751 and EN 14214. Also reported are lubricity, heat of combustion, and Gardner color, along with a comparison of CSME to soybean oil methyl esters (SME). CSME exhibited higher oxidative stability, superior low temperature properties, and lower iodine value than SME. In summary, CSME has excellent fuel properties as a result of its unique fatty acid composition.

  19. Flow-induced crystallization of a nano composite of poly(butylene adipate-co-terephthalate)/montmorillonite; Cinetica de cristalizacao induzida por fluxo de nanocomposito de poli(butileno adipato-co-tereftalato)/montmorilonita

    Energy Technology Data Exchange (ETDEWEB)

    Bonel, Alan B [Universidade Federal de Sao Carlos. UFSCar, Departamento de Engenharia de Materiais DEMa, SP (Brazil); Rego, Bruna T; Beatrice, Cesar A.G.; Marini, Juliano; Bretas, Rosario E.S., E-mail: bretas@ufscar.br [Universidade Federal de Sao Carlos. UFSCar, Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais, SP (Brazil)

    2011-07-01

    Poly(butylene adipate-co-terephthalate) (PBAT) with 5wt% of an organically modified montmorillonite with polar surfactant was prepared by melt blending in a co-rotational twin-screw extruder at 160 degree C. 100rpm and 1 kg/h. Both pure polymer and nano composite were characterized by wide measurements. The study of the flow-induced crystallization was also done by rheological measurements, monitoring the viscosity as a function of time. The nano clay's lamellas were intercalated in the polymer m loss moduli of the nano composite, at low frequencies, showed that the particles of the nano clay were well dispersed and distributed thru the PBAT matrix. Finally, the presence of the nano clay's particles reduced the induction tim crystals growth, due to the strong interactions with the PBAT chains. (author)

  20. Ester Tuiksoo võitleb viina puhtuse eest / Ester Tuiksoo ; interv. Silja Lättemäe

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2006-01-01

    Põllumajandusminister Ester Tuiksoo lubab Euroopa Liidu piiritusjookide määruse eelnõu arutusel kaitsta seisukohta, et viinaks tuleb pidada üksnes teraviljast või kartulist valmistatud piiritusjooki

  1. Request from the Phthalate Esters Panel of the American Chemistry Council for correction of EPA's Action Plan for Phthalate Esters

    Science.gov (United States)

    The Phthalate Esters Panel (Panel) of the American Chemistry Council submits this Request for Correction to EPA under the Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility, and Integrity, of Information Disseminated by the Environmental Protection Agency

  2. Enzymatically and reductively degradable α-amino acid-based poly(ester amide)s: synthesis, cell compatibility, and intracellular anticancer drug delivery.

    Science.gov (United States)

    Sun, Huanli; Cheng, Ru; Deng, Chao; Meng, Fenghua; Dias, Aylvin A; Hendriks, Marc; Feijen, Jan; Zhong, Zhiyuan

    2015-02-09

    A novel and versatile family of enzymatically and reductively degradable α-amino acid-based poly(ester amide)s (SS-PEAs) were developed from solution polycondensation of disulfide-containing di-p-toluenesulfonic acid salts of bis-l-phenylalanine diesters (SS-Phe-2TsOH) with di-p-nitrophenyl adipate (NA) in N,N-dimethylformamide (DMF). SS-PEAs with Mn ranging from 16.6 to 23.6 kg/mol were obtained, depending on NA/SS-Phe-2TsOH molar ratios. The chemical structures of SS-PEAs were confirmed by (1)H NMR and FTIR spectra. Thermal analyses showed that the obtained SS-PEAs were amorphous with a glass transition temperature (Tg) in the range of 35.2-39.5 °C. The in vitro degradation studies of SS-PEA films revealed that SS-PEAs underwent surface erosion in the presence of 0.1 mg/mL α-chymotrypsin and bulk degradation under a reductive environment containing 10 mM dithiothreitol (DTT). The preliminary cell culture studies displayed that SS-PEA films could well support adhesion and proliferation of L929 fibroblast cells, indicating that SS-PEAs have excellent cell compatibility. The nanoparticles prepared from SS-PEA with PVA as a surfactant had an average size of 167 nm in phosphate buffer (PB, 10 mM, pH 7.4). SS-PEA nanoparticles while stable under physiological environment undergo rapid disintegration under an enzymatic or reductive condition. The in vitro drug release studies showed that DOX release was accelerated in the presence of 0.1 mg/mL α-chymotrypsin or 10 mM DTT. Confocal microscopy observation displayed that SS-PEA nanoparticles effectively transported DOX into both drug-sensitive and -resistant MCF-7 cells. MTT assays revealed that DOX-loaded SS-PEA nanoparticles had a high antitumor activity approaching that of free DOX in drug-sensitive MCF-7 cells, while more than 10 times higher than free DOX in drug-resistant MCF-7/ADR cells. These enzymatically and reductively degradable α-amino acid-based poly(ester amide)s have provided an appealing platform for

  3. Neutral lipid biosynthesis in engineered Escherichia coli: jojoba oil-like wax esters and fatty acid butyl esters.

    Science.gov (United States)

    Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

    2006-02-01

    Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant Escherichia coli strain by coexpression of a fatty alcohol-producing bifunctional acyl-coenzyme A reductase from the jojoba plant and a bacterial wax ester synthase from Acinetobacter baylyi strain ADP1, catalyzing the esterification of fatty alcohols and coenzyme A thioesters of fatty acids. In the presence of oleate, jojoba oil-like wax esters such as palmityl oleate, palmityl palmitoleate, and oleyl oleate were produced, amounting to up to ca. 1% of the cellular dry weight. In addition to wax esters, fatty acid butyl esters were unexpectedly observed in the presence of oleate. The latter could be attributed to solvent residues of 1-butanol present in the medium component, Bacto tryptone. Neutral lipids produced in recombinant E. coli were accumulated as intracytoplasmic inclusions, demonstrating that the formation and structural integrity of bacterial lipid bodies do not require specific structural proteins. This is the first report on substantial biosynthesis and accumulation of neutral lipids in E. coli, which might open new perspectives for the biotechnological production of cheap jojoba oil equivalents from inexpensive resources employing recombinant microorganisms.

  4. Lubricating and Waxy Esters. VI. Effect of Symmetry about Ester on Crystallization of Linear Monoester Isomers

    Directory of Open Access Journals (Sweden)

    Laziz Bouzidi

    2014-08-01

    Full Text Available The crystal structure development of jojoba-like esters incorporating either 1-decenoic acid and/or 1-decenol, namely octadec-9-enyl dec-9-enoate (JLE-281, and its isomer dec-9-enyl oleate (JLE-282 was investigated to reveal the effect of symmetry about the ester group on crystallization of aliphatic fatty monoesters. The phase transformation path was investigated with temperature-time resolved X-ray diffraction during stepped isothermal crystallization, and while cooling from the melt at a fixed rate. Startling differences in phase behavior were uncovered between the isomers. When stepped isothermals were used, selective extinctions occurred at a transition temperature for JLE-281 but not for JLE-282. The extinctions, which are due to dramatic changes in the electronic density of certain families of planes, indicate a phase transition attributed to a brusque rearrangement of the oxygen atoms in the crystal subcell. The phase transition did not occur when the JLEs were cooled continuously. The crucial role played by the position of the alkyl chain and its orientation relative to the easy rotation site of the C–O bond in the phase trajectories of the JLEs was particularly highlighted.

  5. Extraction and Liquid Chromatography-Tandem Mass Spectrometry Detection of 3-Monochloropropanediol Esters and Glycidyl Esters in Infant Formula.

    Science.gov (United States)

    Leigh, Jessica K; MacMahon, Shaun

    2016-12-14

    A method was developed for the extraction of fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD) and glycidol from infant formula, followed by quantitative analysis of the extracts using liquid chromatography-tandem mass spectrometry (LC-MS/MS). These process-induced chemical contaminants are found in refined vegetable oils, and studies have shown that they are potentially carcinogenic and/or genotoxic, making their presence in edible oils (and processed foods containing these oils) a potential health risk. The extraction procedure involves a liquid-liquid extraction, where powdered infant formula is dissolved in water and extracted with ethyl acetate. Following shaking, centrifugation, and drying of the organic phase, the resulting fat extract is cleaned-up using solid-phase extraction and analyzed by LC-MS/MS. Method performance was confirmed by verifying the percent recovery of each 3-MCPD and glycidyl ester in a homemade powdered infant formula reference material. Average ester recoveries in the reference material ranged from 84.9 to 109.0% (0.6-9.5% RSD). The method was also validated by fortifying three varieties of commercial infant formulas with a 3-MCPD and glycidyl ester solution. Average recoveries of the esters across all concentrations and varieties of infant formula ranged from 88.7 to 107.5% (1.0-9.5% RSD). Based on the validation results, this method is suitable for producing 3-MCPD and glycidyl ester occurrence data in all commercially available varieties of infant formula.

  6. Sorption of organophosphate esters by carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Wei; Yan, Li [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Duan, Jinming [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an 710055 (China); Jing, Chuanyong, E-mail: cyjing@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)

    2014-05-01

    Graphical abstract: The interfacial interactions between the OPE molecules and CNTs. - Highlights: • Oxygen-containing groups on CNTs change the sorption property for OPEs. • Molecular configuration of OPEs has insignificant impact on their sorption. • Hydrophobic, π–π EDA and Brønsted acid–base interaction occurred between the CNTs and OPEs. - Abstract: Insights from the molecular-level mechanism of sorption of organophosphate esters (OPEs) on carbon nanotubes (CNTs) can further our understanding of the fate and transport of OPEs in the environment. The motivation for our study was to explore the sorption process of OPEs on multi-walled CNTs (MWCNTs), single-walled CNTs (SWCNTs) and their oxidized counterparts (O-MWCNTs and O-SWCNTs), and its molecular mechanism over a wide concentration range. The sorption isotherm results revealed that the hydrophobicity of OPEs dominated their affinities on a given CNT and the π–π electron donor–acceptor (EDA) interaction also played an important role in the sorption of aromatic OPEs. This π–π EDA interaction, verified with Raman and FT-IR spectroscopy, could restrict the radial vibration of SWCNTs and affect the deformation vibration γ(CH) bands of OPE molecules. The OPE surface coverage on CNTs, estimated using the nonlinear Dubinin–Ashtakhov model, indicated that the oxygen-containing functional groups on CNTs could interact with water molecules by H-bonding, resulting in a decrease in effective sorption sites. In addition, FTIR analysis also confirmed the occurrence of Brønsted acid–base interactions between OPEs and surface OH groups of SWCNTs. Our results should provide mechanistic insights into the sorption mechanism of OPE contaminants on CNTs.

  7. Optimization of an Indirect Enzymatic Method for the Simultaneous Analysis of 3-MCPD, 2-MCPD, and Glycidyl Esters in Edible Oils.

    Science.gov (United States)

    Koyama, Kazuo; Miyazaki, Kinuko; Abe, Kousuke; Ikuta, Keiich; Egawa, Yoshitsugu; Kitta, Tadashi; Kido, Hirotsugu; Sano, Takashi; Takahashi, Yukinari; Nezu, Toru; Nohara, Hidenori; Miyashita, Takashi; Yada, Hiroshi; Yamazaki, Kumiko; Watanabe, Yomi

    2015-01-01

    We developed a novel, indirect enzymatic method for the analysis of fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPD), 2-monochloro-1,3-propanediol (2-MCPD), and glycidol (Gly) in edible oils and fats. Using this method, the ester analytes were rapidly cleavaged by Candida rugosa lipase at room temperature for 0.5 h. As a result of the simultaneous hydrolysis and bromination steps, 3-MCPD esters, 2-MCPD esters, and glycidyl esters were converted to free 3-MCPD, 2-MCPD, and 3-monobromo-1,2-propanediol (3-MBPD), respectively. After the addition of internal standards, the mixtures were washed with hexane, derivatized with phenylboronic acid, and analyzed by gas chromatography-mass spectrometer (GC-MS). The analytical method was evaluated in preliminary and feasibility studies performed by 13 laboratories. The preliminary study from 4 laboratories showed the reproducibility (RSD R ) of 3-MCPD and 2-MCPD in extra virgin olive (EVO) oil, semi-solid palm oil, and solid palm oil. However, the RSDR and recoveries of Gly in the palm oil samples were not satisfactory. The Gly content of refrigerated palm oil samples decreased whereas the samples at room temperature were stable for three months, and this may be due to the depletion of Gly during cold storage. The feasibility studies performed by all 13 laboratories were conducted based on modifications of the shaking conditions for ester cleavage, the conditions of Gly bromination, and the removal of gel formed by residual lipase. Satisfactory RSDR were obtained for EVO oil samples spiked with standard esters (4.4% for 3-MCPD, 11.2% for 2-MCPD, and 6.6% for Gly).

  8. ESR study of electron reactions with esters and triglycerides

    International Nuclear Information System (INIS)

    Sevilla, M.D.; Morehouse, K.M.; Swarts, S.

    1981-01-01

    Reactions which occurred after electron attachment at 77K to a number of small carboxylic acid esters and triglycerides in an aqueous glass are reported. Most ester anions are found to decay on warming to form alkyl radicals by β scission: RC(O - )OR' → RCO 2 - + R'.. The alkyl radical (R'.) produced by annealing is found to abstract hydrogen from the parent ester at an α-carbon site, R'.+ R''CH 2 CO 2 R' → R''CHCO 2 R', or in the case of ethyl formate from the formate hydrogen, CH 3 CH 2 .+ HCO 2 C 2 H 5 → C 2 H 6 +.CO 2 C 2 H 5 . Results found for the methyl formate anion suggest hydrogen abstraction by the anion itself may compete with alkyl radical formation. The anion of the triglyceride triacetin is found to undergo an analogous mechanism to the ester anions producing the propane diol diester radical, .CH 2 CH(Ac)CH 2 (Ac), Ac = acetate. This species subsequently abstracts hydrogen from the parent compound to produce the α-carbon radical, .CH 2 CO 2 R. Results found after annealing the tripropionin radical anion give evidence for abstraction from the α carbon in the propionate side groups producing CH 3 CHCO 2 R. Studies of a γ-irradiated ester (ethyl myristate) and two triglycerides (tripalmitin and tristearin) yield results which suggest that the mechanism of ester anion decay found in aqueous glasses applies to γ-irradiated neat long-chain esters and triglycerides. Results found in this work are compared to the results of product analysis

  9. Continuous production of fatty acid ethyl esters from soybean oil at supercritical conditions - doi: 10.4025/actascitechnol.v34i2.11255

    Directory of Open Access Journals (Sweden)

    Camila da Silva

    2012-03-01

    Full Text Available This work reports the production of fatty acid ethyl esters (FAEE from the transesterification of soybean oil in supercritical ethanol in a continuous catalyst-free process using different reactor configurations. Experiments were performed in a tubular reactor in one-step reaction and experimentally simulating two reactors, one operated in series and the other a recycle reactor. The reaction products were analyzed for their content of residual triglycerides, glycerol, monoglycerides, diglycerides, ethyl esters and decomposition. Results show that the configurations studied with intermediate separation of glycerol afford higher conversions of vegetable oil to their fatty acid ethyl esters derivatives when compared to the one-step reaction, with relatively low decomposition of fatty acids (< 5.0 wt%.

  10. Chromium–tungsten–titanium mixed oxides solid catalyst for fatty acid methyl ester synthesis from palm fatty acid distillate

    International Nuclear Information System (INIS)

    Wan, Zuraida; Hameed, B.H.

    2014-01-01

    Highlights: • Chromium–tungsten–titanium mixed oxides as solid catalyst. • Catalyst used for esterification of palm fatty acid distillate to methyl esters. • The maximum methyl ester content is 83%. • Catalyst has shown good activity and can be recycled for 4 times. - Abstract: Chromium–tungsten–titanium mixed oxides solid catalysts were prepared and evaluated in the esterification of palm fatty acid distillate (PFAD) to produce fatty acid methyl ester (FAME). Esterification was conducted in a batch reactor at 110–200 °C temperature ranges. The catalysts were characterized by several techniques such as BET, TEM, FTIR, TGA, XRD, EDX and SEM. The treatment conditions during catalyst preparation, effect of reaction parameters, leaching of the active species and the recycled use of the catalyst were investigated. The catalyst with formula CrWTiO 2 was found to be the most active with maximum FAME content of 83% obtained at best reaction conditions of 170 °C for 3 h, 2:1 (methanol to oil molar ratio) and 2 wt.% catalyst dosage. The catalyst can be recycled for 4 times. The results revealed CrWTiO 2 good potentials for use in esterification of high acid value oil

  11. The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components.

    Science.gov (United States)

    Zulkurnain, Musfirah; Lai, Oi Ming; Latip, Razam Abdul; Nehdi, Imededdine Arbi; Ling, Tau Chuan; Tan, Chin Ping

    2012-11-15

    The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Local Content

    CSIR Research Space (South Africa)

    Gibberd, Jeremy

    2016-10-01

    Full Text Available Local content refers to materials and products made in a country as opposed those that are imported. There is an increasing interest in the concept of local content as a means of supporting local economies and providing jobs (Belderbos & Sleuwaegen...

  13. Effect of temperature stress on protein methyl esters

    International Nuclear Information System (INIS)

    Welch, W.; Kracaw, K.

    1986-01-01

    Protein methyl esters have been implicated in a number of physiological processes. They have measured the effect of temperature stress on the levels of protein methyl esters in the mesophilic fungus Penicillium chrysogenum (PCPS) and the thermophilic fungus P. duponti (PD). PD and PCPS were incubated with [methyl- 3 H]methionine. The mycelia were collected by filtration, frozen in liquid nitrogen and ground to a fine powder. The nitrogen powder was extracted with either phosphate buffer or with SDS, glycerol, phosphate, 2-mercaptoethanol. Insoluble material was removed by centrifugation. The supernatants were assayed for protein methyl esters. The released [ 3 H]methanol was extracted into toluene:isoamyl alcohol (3:2) and quantitated by liquid scintillation. The production of volatile methanol was confirmed by use of Conway diffusion cells. Soluble proteins accounted for about one-fourth of the total protein methyl ester extracted by SDS. In PCPS, the SDS extracted proteins have about three times the level of esterification of the soluble proteins whereas in PD there is little difference between soluble and SDS extracted protein. The level of protein esterification in PD is about one-tenth that observed in PCPS. Temperature stress caused large changes in the level of protein esterification. The data suggest protein methyl esters may contribute to the adaptation to environmental stress

  14. Influence of ester-modified lipids on bilayer structure.

    Science.gov (United States)

    Villanueva, Diana Y; Lim, Joseph B; Klauda, Jeffery B

    2013-11-19

    Lipid membranes function as barriers for cells to prevent unwanted chemicals from entering the cell and wanted chemicals from leaving. Because of their hydrophobic interior, membranes do not allow water to penetrate beyond the headgroup region. We performed molecular simulations to examine the effects of ester-modified lipids, which contain ester groups along their hydrocarbon chains, on bilayer structure. We chose two lipids from those presented in Menger et al. [J. Am. Chem. Soc. 2006, 128, 14034] with ester groups in (1) the upper half of the lipid chain (MEPC) and (2) the middle and end of the lipid chain (MGPC). MGPC (30%)/POPC bilayers formed stable water pores of diameter 5-7 Å, but MGPC (22%)/POPC and MEPC (30%)/POPC bilayers did not form these defects. These pores were similar to those formed during electroporation; i.e., the head groups lined the pore and allowed water and ions to transport across the bilayer. However, we found that lateral organization of the MGPC lipids into clusters, instead of an electric field or charge disparity as in electroporation, was essential for pore formation. On the basis of this, we propose an overall mechanism for pore formation. The similarities between the ester-modified lipids and byproducts of lipid peroxidation with multiple hydrophilic groups in the middle of the chain suggest that free radical reactions with unsaturated lipids and sterols result in fundamental changes that may be similar to what is seen in bilayers with ester-modified lipids.

  15. Solid state crystallisation of oligosaccharide ester derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Elaine Ann

    2002-07-01

    An investigation of the solid state properties of oligosaccharide ester derivatives (OEDs) with potential applications in drug delivery has been carried out. The amorphous form of two OEDs, trehalose octa-acetate (TOAC) and 6:6'-di-({beta}-tetraacetyl glucuronyl)-hexaacetyl trehalose (TR153), was investigated as a matrix for the sustained release of active ingredients. The matrices showed a tendency to crystallise and so polymorph screens were performed to provide crystalline samples for structural analysis. The crystal structures of TOAC methanolate and TR153 acetonitrile solvate have been determined by single-crystal laboratory X-ray diffraction. TOAC methanolate crystallises in the orthorhombic space group P2{sub 1}2{sub 1}2{sub 1} with a = 15.429(18) A, b = 17.934(19) A and c = 13.518(4) A at 123 K. The structure is isomorphous with the previously reported structure of TOAC monohydrate form II. TR153 acetonitrile solvate crystallises in the monoclinic spacegroup C2 with a = 30:160(6) A, b = 11.878(3) A, c 20.6645(5) A and {beta} = 115.027 (10) deg at 123 K. The crystal structures of both TOAC methanolate and TR153 acetonitrile solvate are stabilised by complex networks of intermolecular C--H...O contacts. Two model compounds were selected for dissolution studies: diltiazem hydrochloride, as a water- soluble organic salt, and ketoprofen as a poorly water-soluble organic compound. Dissolution of both compounds from amorphous TOAC and TR153 matrices was investigated. The release of both drugs was more rapid and complete from TOAC matrices than from TR153 matrices, with both matrices showing a tendency to crystallise (devitrify) during the course of the dissolution experiments. This tendency was greater for the TOAC matrix, which transformed to the extent of ca. 100% within 48 hours. The available evidence suggests that devitrification of the matrix in contact with water produces a polycrystalline, non-monolithic structure rich in microscopic cracks and pores

  16. Solid state crystallisation of oligosaccharide ester derivatives

    International Nuclear Information System (INIS)

    Wright, Elaine Ann

    2002-01-01

    An investigation of the solid state properties of oligosaccharide ester derivatives (OEDs) with potential applications in drug delivery has been carried out. The amorphous form of two OEDs, trehalose octa-acetate (TOAC) and 6:6'-di-(β-tetraacetyl glucuronyl)-hexaacetyl trehalose (TR153), was investigated as a matrix for the sustained release of active ingredients. The matrices showed a tendency to crystallise and so polymorph screens were performed to provide crystalline samples for structural analysis. The crystal structures of TOAC methanolate and TR153 acetonitrile solvate have been determined by single-crystal laboratory X-ray diffraction. TOAC methanolate crystallises in the orthorhombic space group P2 1 2 1 2 1 with a = 15.429(18) A, b = 17.934(19) A and c = 13.518(4) A at 123 K. The structure is isomorphous with the previously reported structure of TOAC monohydrate form II. TR153 acetonitrile solvate crystallises in the monoclinic spacegroup C2 with a = 30:160(6) A, b = 11.878(3) A, c 20.6645(5) A and β = 115.027 (10) deg at 123 K. The crystal structures of both TOAC methanolate and TR153 acetonitrile solvate are stabilised by complex networks of intermolecular C--H...O contacts. Two model compounds were selected for dissolution studies: diltiazem hydrochloride, as a water- soluble organic salt, and ketoprofen as a poorly water-soluble organic compound. Dissolution of both compounds from amorphous TOAC and TR153 matrices was investigated. The release of both drugs was more rapid and complete from TOAC matrices than from TR153 matrices, with both matrices showing a tendency to crystallise (devitrify) during the course of the dissolution experiments. This tendency was greater for the TOAC matrix, which transformed to the extent of ca. 100% within 48 hours. The available evidence suggests that devitrification of the matrix in contact with water produces a polycrystalline, non-monolithic structure rich in microscopic cracks and pores which allows diffusion of

  17. How Well Does BODIPY-Cholesteryl Ester Mimic Unlabeled Cholesteryl Esters in High Density Lipoprotein Particles?

    DEFF Research Database (Denmark)

    Karilainen, Topi; Vuorela, Timo; Vattulainen, Ilpo

    2015-01-01

    We compare the behavior of unlabeled and BODIPY-labeled cholesteryl ester (CE) in high density lipoprotein by atomistic molecular dynamics simulations. We find through replica exchange umbrella sampling and unbiased molecular dynamics simulations that BODIPY labeling has no significant effect...... on the partitioning of CE between HDL and the water phase. However, BODIPY-CE was observed to diffuse more slowly and locate itself closer to the HDL-water interface than CE due to the BODIPY probe that is constrained to the surface region, and because the CE body in BODIPY-CE prefers to align itself away from...... the HDL surface. The implications as to the suitability of BODIPY to explore lipoprotein properties are discussed....

  18. Preparation and characterization of aliphatic diphenyl esters intended as precursors for polyesters

    DEFF Research Database (Denmark)

    Hvilsted, S.; Andruzzi, F.; Cerrai, P.

    1991-01-01

    An extensive number of aliphatic diphenyl esters, C6H5OOC(CH2)nCOOC6H5 (n = O,...,8,10,11,12,14), have been prepared in pure form. The crystalline melting points these esters exhibit an odd-even temperature behaviour, with the higher-melting even series (n even) displaying a minimum for n = 8 while...... based on similar data from phenyl esters, interpreted as the results of an apparent macrocyclic conformation of the larger diphenyl esters. High-performance size exclusion chromatography (s.e.c.) of diphenyl esters, phenyl esters, aromatic and linear hydrocarbons in tetrahydrofuran, toluene...

  19. COMBUSTION CHARACTERISTICS OF DIESEL ENGINE OPERATING ON JATROPHA OIL METHYL ESTER

    Directory of Open Access Journals (Sweden)

    Doddayaraganalu Amasegoda Dhananjaya

    2010-01-01

    Full Text Available Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed interest of scientific community to look for alternative fuels of bio-origin such as vegetable oils. Vegetable oils can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Non-edible vegetable oils such as jatropha oil, linseed oil, mahua oil, rice bran oil, karanji oil, etc., are potentially effective diesel substitute. Vegetable oils have reasonable energy content. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in diesel engines with very little or no engine modifications. This is because it has combustion characteristics similar to petroleum diesel. The current paper reports a study carried out to investigate the combustion, performance and emission characteristics of jatropha oil methyl ester and its blend B20 (80% petroleum diesel and 20% jatropha oil methyl ester and diesel fuel on a single-cylinder, four-stroke, direct injections, water cooled diesel engine. This study gives the comparative measures of brake thermal efficiency, brake specific energy consumption, smoke opacity, HC, NOx, ignition delay, cylinder peak pressure, and peak heat release rates. The engine performance in terms of higher thermal efficiency and lower emissions of blend B20 fuel operation was observed and compared with jatropha oil methyl ester and petroleum diesel fuel for injection timing of 20° bTDC, 23° bTDC and 26° bTDC at injection opening pressure of 220 bar.

  20. Boric Ester-Type Molten Salt via Dehydrocoupling Reaction

    Directory of Open Access Journals (Sweden)

    Noriyoshi Matsumi

    2014-11-01

    Full Text Available Novel boric ester-type molten salt was prepared using 1-(2-hydroxyethyl-3-methylimidazolium chloride as a key starting material. After an ion exchange reaction of 1-(2-hydroxyethyl-3-methylimidazolium chloride with lithium (bis-(trifluoromethanesulfonyl imide (LiNTf2, the resulting 1-(2-hydroxyethyl-3-methylimidazolium NTf2 was reacted with 9-borabicyclo[3.3.1]nonane (9-BBN to give the desired boric ester-type molten salt in a moderate yield. The structure of the boric ester-type molten salt was supported by 1H-, 13C-, 11B- and 19F-NMR spectra. In the presence of two different kinds of lithium salts, the matrices showed an ionic conductivity in the range of 1.1 × 10−4–1.6 × 10−5 S cm−1 at 51 °C. This was higher than other organoboron molten salts ever reported.

  1. Ester oxidation on an aluminum surface using chemiluminescence

    Science.gov (United States)

    Jones, William R., Jr.; Meador, Michael A.; Morales, Wilfredo

    1986-01-01

    The oxidation characteristics of a pure ester (trimethyolpropane triheptanoate) were studied by using a chemiluminescence technique. Tests were run in a thin film microoxidation apparatus with an aluminum alloy catalyst. Conditions included a pure oxygen atmosphere and a temperature range of 176 to 206 C. Results indicated that oxidation of the ester (containing .001 M diphenylanthracene as an intensifier) was accompanied by emission of light. The maximum intensity of light emission was a function of the amount of ester, the concentration of intensifier, and the test temperature. The induction period, or the time to reach one-half of maximum intensity was inversely proportional to test temperature. Decreases in light emission at the later stages of a test were caused by depletion of the intensifier.

  2. Three new fatty acid esters from the mushroom Boletus pseudocalopus.

    Science.gov (United States)

    Kim, Ki Hyun; Choi, Sang Un; Lee, Kang Ro

    2012-06-01

    A bioassay-guided fractionation and chemical investigation of a MeOH extract of the Korean wild mushroom Boletus pseudocalopus resulted in the identification of three new fatty acid esters, named calopusins A-C (1-3), along with two known fatty acid methyl esters (4-5). These new compounds are structurally unique fatty acid esters with a 2,3-butanediol moiety. Their structures were elucidated through 1D- and 2D-NMR spectroscopic data and GC-MS analysis as well as a modified Mosher's method. The new compounds 1-3 showed significant inhibitory activity against the proliferation of the tested cancer cell lines with IC(50) values in the range 2.77-12.51 μM.

  3. Long-Acting Diclofenac Ester Prodrugs for Joint Injection

    DEFF Research Database (Denmark)

    Mertz, Nina; Larsen, Susan Weng; Kristensen, Jesper

    2016-01-01

    A prodrug approach for local and sustained diclofenac action after injection into joints based on ester prodrugs having a pH-dependent solubility is presented. Inherent ester prodrug properties influencing the duration of action include their pH-dependent solubility and charge state, as well...... as susceptibility to undergo esterase facilitated hydrolysis. In this study, physicochemical properties and pH rate profiles of 3 diclofenac ester prodrugs differing with respect to the spacer carbon chain length between the drug and the imidazole-based promoiety were determined and a rate equation for prodrug...... degradation in aqueous solution in the pH range 1-10 was derived. In the pH range 6-10, the prodrugs were subject to parallel degradation to yield diclofenac and an indolinone derivative. The prodrug degradation was found to be about 6-fold faster in 80% (vol/vol) human plasma as compared to 80% (vol...

  4. Maximization of fructose esters synthesis by response surface methodology.

    Science.gov (United States)

    Neta, Nair Sampaio; Peres, António M; Teixeira, José A; Rodrigues, Ligia R

    2011-07-01

    Enzymatic synthesis of fructose fatty acid ester was performed in organic solvent media, using a purified lipase from Candida antartica B immobilized in acrylic resin. Response surface methodology with a central composite rotatable design based on five levels was implemented to optimize three experimental operating conditions (temperature, agitation and reaction time). A statistical significant cubic model was established. Temperature and reaction time were found to be the most significant parameters. The optimum operational conditions for maximizing the synthesis of fructose esters were 57.1°C, 100 rpm and 37.8 h. The model was validated in the identified optimal conditions to check its adequacy and accuracy, and an experimental esterification percentage of 88.4% (±0.3%) was obtained. These results showed that an improvement of the enzymatic synthesis of fructose esters was obtained under the optimized conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Saliva-catalyzed hydrolysis of a ketobemidone ester prodrug

    DEFF Research Database (Denmark)

    Hansen, L.B.; Christrup, Lona Louring; Bundgaard, H.

    1992-01-01

    Saliva enzyme-catalysed hydrolysis of ester prodrugs or drugs containing sensitive ester groups may be a limiting factor for the buccal absorption of such compounds. Using the isopropyl carbonate ester of ketobemidone as a model substance of a hydrolysis-sensitive prodrug the esterase activity...... of human saliva has been characterized as a function of various factors. The esterase activity was found to decrease rapidly upon storage of the saliva at 37°C. The activity increased with increasing pH in the range 4.5-7.4 and with increasing salivation flow rate up to a rate of 0.9 ml min. Under resting...... conditions, the flow rate was about 0.2 ml min which implied a greatly decreased esterase activity. The activity was highest after fasting and decreased after intake of a meal. The intraindividual variation in the saliva esterase activity was small whereas a larger interindividual variation was found....

  6. Differential Partitioning of Triterpenes and Triterpene Esters in Apple Peel.

    Science.gov (United States)

    Poirier, Brenton C; Buchanan, David A; Rudell, David R; Mattheis, James P

    2018-02-28

    Apple peel is a rich source of secondary metabolites, and several studies have outlined the dietary health benefits of ursane-type triterpenes in apple. Changes in triterpene metabolism have also been associated with the development of superficial scald, a postharvest apple peel browning disorder, and postharvest applications of diphenylamine and 1-methylcyclopropene. Previously, studies have generated metabolite profiles for whole apple peel or apple wax. In this study, we report separate metabolic analyses of isolated wax fractions and peel epidermis to investigate the spatial distribution of secondary metabolites in peel. In addition to examining previously reported triterpenes, we identified several unreported fatty acid esters of ursane-type triterpenes (C14-C22). All free pentacyclic triterpenes and triterpenic acids, with the exception of β-amyrin, were localized in the wax layer, along with esters of ursolic acid and uvaol. All sterols, sterol derivatives and α-amyrin esters were localized in the dewaxed peel epidermis.

  7. Functionalization of epoxy esters with alcohols as stoichiometric reagents.

    Science.gov (United States)

    Pavlović, Dona; Modec, Barbara; Dolenc, Darko

    2015-01-01

    Glycidyl esters, frequently employed as reactive groups on polymeric supports, were functionalized with alcohols as stoichiometric reagents, yielding β-alkoxyalcohols. Among the solvents studied, best results were obtained in ethers in the presence of a strong proton acid as a catalyst. Alcohols include simple alkanols, diols, protected polyols, 3-butyn-1-ol 3-hydroxypropanenitrile and cholesterol. This protocol represents a convenient way for introduction of various functionalities onto epoxy-functionalized polymers. Under the reaction conditions, some side reactions take place, mostly due to the reactive ester group and water present in the reaction mixture.

  8. Jojoba methyl ester as a diesel fuel substitute: Preparation and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Radwan, M.S.; Ismail, M.A.; Elfeky, S.M.S.; Abu-Elyazeed, O.S.M. [Mechanical Power Engineering Department, Faculty of Engineering at Mattaria, University of Helwan, Masakin Elhelmia, Mattaria, Cairo 11718 (Egypt)

    2007-02-15

    The aim of the present work is to prepare jojoba methyl ester (JME) as a diesel fuel substitute. This was carried out experimentally and its chemical and physical properties were determined. Esterification method is used to produce methyl ester from raw jojoba oil. This method is optimized to produce the highest amount of fuel using a minimum amount of methyl alcohol. To achieve the above aim, a test rig for fuel production was developed. To measure the JME burning velocity a constant volume bomb was developed. The bomb was fully instrumented with a piezoelectric pressure transducer, charge amplifier, digital storage oscilloscope, A/D converter and a personal computer. Several grades of fuel were produced but, two grades only were selected and tested as an economical alternative fuel. The chemical and physical properties of these grades of fuel are measured as well as the laminar burning velocity. It is found that JME liquid fuel exhibited lower burning velocities than iso-octane. The new fuel is found to be suitable for compression ignition engine particularly in the indirect-injection ones, while for direct-injection, and high-speed engines fuel modifications are required. The new fuel is safe, has no sulphur content and reduces the engine wear as well as lengthens the lifetime of lubricating oil. (author)

  9. Experimental investigation on a diesel engine using neem oil and its methyl ester

    Directory of Open Access Journals (Sweden)

    Sivalakshmi S.

    2011-01-01

    Full Text Available Fuel crisis and environmental concerns have led to look for alternative fuels of bio-origin sources such as vegetable oils, which can be produced from forests, vegetable oil crops and oil bearing biomass materials. Vegetable oils have energy content comparable to diesel fuel. The effect of neem oil (NeO and its methyl ester (NOME on a direct injected four stroke, single cylinder diesel engine combustion, performance and emission is investigated in this paper. The results show that at full load, peak cylinder pressure is higher for NOME; peak heat release rate during the premixed combustion phase is lower for neat NeO and NOME. Ignition delay is lower for neat NeO and NOME when compared with diesel at full load. The brake thermal efficiency is slightly lower for NeO at all engine loads, but in the case of NOME slightly higher at full load. It has been observed that there is a reduction in NOx emission for neem oil and its methyl ester along with an increase in CO, HC and smoke emissions.

  10. Occurrence of 3-MCPD fatty acid esters in human breast milk.

    Science.gov (United States)

    Zelinková, Z; Novotný, O; Schůrek, J; Velísek, J; Hajslová, J; Dolezal, M

    2008-06-01

    A series of twelve breast milk samples were analysed by gas chromatography-mass spectrometry (GC/MS) operated in selected ion monitoring mode for 3-chloropropane-1,2-diol (3-MCPD). Whilst none of the samples contained 3-MCPD above the limit of detection of 3 microg kg(-1) milk, all contained high amounts of 3-MCPD esterified with higher fatty acids. The levels of 3-MCPD released by hydrolysis of these esters (bound 3-MCPD) ranged from the limit of detection (300 microg kg(-1), expressed on a fat basis) to 2195 microg kg(-1); with a mean level of bound 3-MCPD of 1014 microg kg(-1), which corresponded to 35.5 microg kg(-1) milk. The presence of bound 3-MCPD was confirmed using orthogonal gas chromatography coupled with high-speed time-of-flight mass spectrometry analysis for four randomly selected breast milk samples. Six breast milks collected from one of the nursing mothers 14-76 days after childbirth contained bound 3-MCPD within the range of 328-2078 microg kg(-1) fat (mean 930 microg kg(-1) fat). The calculated bound 3-MCPD content of these samples was within the range of 6 and 19 microg kg(-1) milk (mean of 12 microg kg(-1) milk). The major types of 3-MCPD esters were the symmetric diesters with lauric, palmitic, and oleic acids, and asymmetric diesters with palmitic acid/oleic acid among which 3-chloro-1,2-propanediol 1,2-dioleate prevailed.

  11. An Improved Enzymatic Indirect Method for Simultaneous Determinations of 3-MCPD Esters and Glycidyl Esters in Fish Oils.

    Science.gov (United States)

    Miyazaki, Kinuko; Koyama, Kazuo

    2017-10-01

    The enzymatic indirect method for simultaneous determinations of 3-chloro-1, 2-propanediol fatty acid esters (3-MCPD-Es) and glycidyl fatty acid esters (Gly-Es) make use of lipase from Candida cylindracea (previously referred to as C. rugosa). Because of low substrate specificity of the lipase for esters of polyunsaturated fatty acids (PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), fish oils high in PUFAs are currently excluded from the range of application of the method. The objective of this study was to make the enzymatic indirect method applicable to fats and oils containing PUFAs. By using a Burkholderia cepacia lipase, and by removing sodium bromide from hydrolysis step and adding it after completion of the hydrolysis step, satisfactory recovery rates of 91-109% for 3-MCPD, and 91-110% for glycidol (Gly) were obtained from an EPA and DHA concentrated sardine oil, three DHA concentrated tuna oils, two fish oils, and five fish-oil based dietary supplements spiked with DHA-esters or oleic acid-esters of 3-MCPD and Gly at 20 mg/kg. Further, results from unspiked samples of seven fish oil based dietary supplements and five DHA concentrated tuna oils analyzed by the improved enzymatic indirect method were compared with the results analyzed by AOCS Cd 29a. For all 3-MCPD, 2-MCPD and Gly, the 95% confidence intervals determined by the weighted Deming regression for slopes and intercepts contained the value of 1 and 0, respectively. It was therefore concluded that the results from the two methods were not statistically different. These results suggest that fish oils high in PUFAs may be included in the range of application for the improved enzymatic indirect method for simultaneous determinations of 3-MCPD and Gly esters in fats and oils.

  12. Unsaturated Fatty Acid Esters Metathesis Catalyzed by Silica Supported WMe5

    KAUST Repository

    Riache, Nassima; Callens, Emmanuel; Talbi, Karima; Basset, Jean-Marie

    2015-01-01

    Metathesis of unsaturated fatty acid esters (FAEs) by silica supported multifunctional W-based catalyst is disclosed. This transformation represents a novel route towards unsaturated di-esters. Especially, the self-metathesis of ethyl undecylenate

  13. N-[11C]methylpiperidine esters as acetylcholinesterase substrates: an in vivo structure-reactivity study

    International Nuclear Information System (INIS)

    Kilbourn, Michael R.; Nguyen, Thinh B.; Snyder, Scott E.; Sherman, Phillip

    1998-01-01

    A series of simple esters incorporating the N-[ 11 C]methylpiperidine structure were examined as in vivo substrates for acetylcholinesterase in mouse brain. 4-N-[ 11 C]Methylpiperidinyl esters, including the acetate, propionate and isobutyrate esters, are good in vivo substrates for mammalian cholinesterases. Introduction of a methyl group at the 4-position of the 4-piperidinol esters, to form the ester of a teritary alcohol, effectively blocks enzymatic action. Methylation of 4- N-[ 11 C]methylpiperidinyl propionate at the 3-position gives a derivative with increased in vivo reactivity toward acetylcholinesterase. Esters of piperidinecarboxylic acids (nipecotic, isonipecotic and pipecolinic acid ethyl esters) are not hydrolyzed by acetylcholinesterase in vivo, nor do they act as in vivo inhibitors of the enzyme. This study has identified simple methods to both increase and decrease the in vivo reactivity of piperidinyl esters toward acetylcholinesterase

  14. Viscosity of aqueous and cyanate ester suspensions containing alumina nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Lawler, Katherine [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    The viscosities of both aqueous and cyanate ester monomer (BECy) based suspensions of alumina nanoparticle were studied. The applications for these suspensions are different: aqueous suspensions of alumina nanoparticles are used in the production of technical ceramics made by slip casting or tape casting, and the BECy based suspensions are being developed for use in an injection-type composite repair resin. In the case of aqueous suspensions, it is advantageous to achieve a high solids content with low viscosity in order to produce a high quality product. The addition of a dispersant is useful so that higher solids content suspensions can be used with lower viscosities. For BECy suspensions, the addition of nanoparticles to the BECy resin is expected to enhance the mechanical properties of the cured composite. The addition of saccharides to aqueous suspensions leads to viscosity reduction. Through DSC measurements it was found that the saccharide molecules formed a solution with water and this resulted in lowering the melting temperature of the free water according to classic freezing point depression. Saccharides also lowered the melting temperature of the bound water, but this followed a different rule. The shear thinning and melting behaviors of the suspensions were used to develop a model based on fractal-type agglomeration. It is believed that the structure of the particle flocs in these suspensions changes with the addition of saccharides which leads to the resultant viscosity decrease. The viscosity of the BECy suspensions increased with solids content, and the viscosity increase was greater than predicted by the classical Einstein equation for dilute suspensions. Instead, the Mooney equation fits the viscosity behavior well from 0-20 vol% solids. The viscosity reduction achieved at high particle loadings by the addition of benzoic acid was also investigated by NMR. It appears that the benzoic acid interacts with the surface of the alumina particle which may

  15. Fundamental Characterization of the Micellar Self-Assembly of Sophorolipid Esters.

    Science.gov (United States)

    Koh, Amanda; Todd, Katherine; Sherbourne, Ezekiel; Gross, Richard A

    2017-06-13

    Surfactants are ubiquitous constituents of commercial and biological systems that function based on complex structure-dependent interactions. Sophorolipid (SL) n-alkyl esters (SL-esters) comprise a group of modified naturally derived glycolipids from Candida bombicola. Herein, micellar self-assembly behavior as a function of SL-ester chain length was studied. Surface tensions as low as 31.2 mN/m and critical micelle concentrations (CMCs) as low as 1.1 μM were attained for diacetylated SL-decyl ester (dASL-DE) and SL-octyl ester, respectively. For deacetylated SL-esters, CMC values reach a lower limit at SL-ester chains above n-butyl (SL-BE, 1-3 μM). This behavior of SL-esters with increasing hydrophobic tail length is unlike other known surfactants. Diffusion-ordered spectroscopy (DOSY) and T 1 relaxation NMR experiments indicate this behavior is due to a change in intramolecular interactions, which impedes the self-assembly of SL-esters with chain lengths above SL-BE. This hypothesis is supported by micellar thermodynamics where a disruption in trends occurs at n-alkyl ester chain lengths above those of SL-BE and SL-hexyl ester (SL-HE). Diacetylated (dA) SL-esters exhibit an even more unusual trend in that CMC increases from 1.75 to 815 μM for SL-ester chain lengths of dASL-BE and dASL-DE, respectively. Foaming studies, performed to reveal the macroscopic implications of SL-ester micellar behavior, show that the observed instability in foams formed using SL-esters are due to coalescence, which highlights the importance of understanding intermicellar interactions. This work reveals that SL-esters are an important new family of green high-performing surfactants with unique structure-property relationships that can be tuned to optimize micellar characteristics.

  16. Ester-free Thiol-X Resins: New Materials with Enhanced Mechanical Behavior and Solvent Resistance

    OpenAIRE

    Podgórski, Maciej; Becka, Eftalda; Chatani, Shunsuke; Claudino, Mauro; Bowman, Christopher N.

    2015-01-01

    A series of thiol-Michael and radical thiol-ene network polymers were successfully prepared from ester-free as well as ester-containing monomer formulations. Polymerization reaction rates, dynamic mechanical analysis, and solvent resistance experiments were performed and compared between compositions with varied ester loading. The incorporation of ester-free alkyl thiol, vinyl sulfone and allylic monomers significantly improved the mechanical properties when compared with commercial, mercapto...

  17. In vitro pharmacokinetics of anti-psoriatic fumaric acid esters

    NARCIS (Netherlands)

    N.H.R. Litjens (Nicolle); E. van Strijen (Elizabeth); C. van Gulpen (Co); H. Mattie (Herman); J.T. van Dissel (Jaap); H.B. Thio (Bing); P.H. Nibbering (Peter)

    2004-01-01

    textabstractBackground: Psoriasis is a chronic inflammatory skin disease that can be successfully treated with a mixture of fumaric acid esters (FAE) formulated as enteric-coated tablets for oral use. These tablets consist of dimethylfumarate (DMF) and salts of monoethylfumarate (MEF) and its main

  18. Evaluation of the Levels of phthalate Ester Plasticizers in Surface ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Gas chromatography (GC) coupled with mass ... Key words: phthalates, acid esters, plasticizers, Ethiope River, surface water, pollution ... waste and emissions arising from burning of refuse ... deepest inland waterways in Africa, is known for its ..... carbon nitride nanocomposites for the solid-phase extraction of phthalate ...

  19. Controlled grafting of cellulose esters using SET-LRP process

    Czech Academy of Sciences Publication Activity Database

    Vlček, Petr; Raus, Vladimír; Janata, Miroslav; Kříž, Jaroslav; Sikora, Antonín

    2011-01-01

    Roč. 49, č. 1 (2011), s. 164-173 ISSN 0887-624X R&D Projects: GA ČR GA106/09/1348 Institutional research plan: CEZ:AV0Z40500505 Keywords : cellulose esters * copolymerization * graft copolymers Subject RIV: JI - Composite Materials Impact factor: 3.919, year: 2011

  20. Effect of Sucrose Esters on the Physicochemical Properties of Wheat ...

    African Journals Online (AJOL)

    In addition, the structure and thermodynamic properties of the modified starch were analyzed by Fourier transform infrared spectroscopy (FITR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Results: The properties of wheat starch changed greatly by adding different sucrose esters to their ...

  1. Hydrolytic Stability of Boronate Ester-Linked Covalent Organic Frameworks

    KAUST Repository

    Li, Huifang

    2018-01-30

    The stability of covalent organic frameworks (COFs) is essential to their applications. However, the common boronate ester-linked COFs are susceptible to attack by nucleophiles (such as water molecules) at the electron-deficient boron sites. To provide an understanding of the hydrolytic stability of the representative boronate ester-linked COF-5 and of the associated hydrolysis mechanisms, density functional theory (DFT) calculations were performed to characterize the hydrolysis reactions of the molecule formed by the condensation of 1,4-phenylenebis(boronic acid) (PBBA) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) monomers; two cases were considered, one dealing with the freestanding molecule and the other with the molecule interacting with COF layers. It was found that the boronate ester (B–O) bond dissociation, which requires one H2O molecule, has a relatively high energy barrier of 22.3 kcal mol−1. However, the presence of an additional H2O molecule significantly accelerates hydrolysis by reducing the energy barrier by a factor of 3. Importantly, the hydrolysis of boronate ester bonds situated in a COF environment follows reaction pathways that are different and have increased energy barriers. These results point to an enhanced hydrolytic stability of COF-5 crystals.

  2. Effect of a novel insulinotropic agent, succinic acid monoethyl ester ...

    Indian Academy of Sciences (India)

    Madhu

    index (AAI) (ratio of HDL-C to total cholesterol) were studied. ... ester; FFA, free falty acids; HDL-C, high density lipoprotein-cholesterol; LDL-C, low density lipoprotein-cholesterol; ..... and impaired catabolism of triglyceride-rich particles. The.

  3. Analysis of phthalate esters contamination in drinking water samples ...

    African Journals Online (AJOL)

    The optimum condition method was successfully applied to the analysis of phthalate esters contamination in bottled drinking water samples. The concentration of DMP, DEP and DBP in drinking water samples were below allowable levels, while the DEHP concentration in three samples was found to be greater than the ...

  4. Polysaccharide esters and their use as binders in coatings

    NARCIS (Netherlands)

    Oostveen, E.A.; Weijnen, J.; Haveren, van J.; Gillard, M.

    2003-01-01

    The invention relates to a polyester obtainable by transesterification or interesterification of: (i) inulin of general formula G(F)n or an acyl ester thereof, wherein G represents a glucose moiety, F represents a fructose moiety, and n is at least 2, and(ii) a drying oil, a semi-drying oil or

  5. Production of both esters and biogas from Mexican poppy | Singh ...

    African Journals Online (AJOL)

    This paper details a dynamic evaluation of a procedure for extracting both, ester and biogas from seeds and waste of Mexican poppy (Argemone mexicana) using simple and inexpensive technique. Results showed that A. mexicana seed contains 30% oil. Through the process of transestrification, oil extracted from seed, ...

  6. Preparation of Jojoba Oil Ester Derivatives for Biodiesel Evaluation

    Science.gov (United States)

    As a result of the increase in commodity vegetable oil prices, it is imperative that non-food oils should be considered as alternative feedstocks for biodiesel production. Jojoba oil is unusual in that it is comprised of wax esters as opposed to the triglycerides found in typical vegetable oils. A...

  7. Poly(ether ester amide)s for tissue engineering

    NARCIS (Netherlands)

    Deschamps, A.A.; van Apeldoorn, Aart A.; de Bruijn, Joost Dick; Grijpma, Dirk W.; Feijen, Jan

    2003-01-01

    Poly(ether ester amide) (PEEA) copolymers based on poly(ethylene glycol) (PEG), 1,4-butanediol and dimethyl-7,12-diaza-6,13-dione-1,18-octadecanedioate were evaluated as scaffold materials for tissue engineering. A PEEA copolymer based on PEG with a molecular weight of 300 g/mol and 25 wt% of soft

  8. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Science.gov (United States)

    2010-04-01

    ... ester copolymer coating may safely be used as a food-contact surface of articles intended for packaging..., and methacrylic acid applied in emulsion form to molded virgin fiber and heat-cured to an insoluble... application of the emulsion may include substances named in this paragraph, in an amount not to exceed that...

  9. Presidendiauto jalakäijate teel / Ester Shank

    Index Scriptorium Estoniae

    Šank, Ester, 1956-

    2003-01-01

    Presidendi pressinõunik Ester Shank selgitab, miks president Arnold Rüütel sõitis eskorauto saatel lauluväljakule Andrea Bocelli ja Annely Peebo kontserdile läbi Kadrioru pargi jalakäijate teed mööda

  10. Ethyl ester purpurine-18 from Gossypium mustelinum (Malvaceae)

    International Nuclear Information System (INIS)

    Silva, Tania Maria Sarmento; Camara, Celso Amorim; Barbosa-Filho, Jose Maria; Giulietti, Ana Maria

    2010-01-01

    The phaeophorbide ethyl ester named Purpurine-18 and the flavonoids quercetin and kaempferol were obtained by chromatographic procedures from the chloroform fraction of aerial parts of Gossypium mustelinum. The structure of these compound was determined by NMR, IR and mass spectra data analysis. This is the first occurrence of this compound in Angiosperm. (author)

  11. New phenolic esters from the resinous exudate of Haplopappus taeda.

    Science.gov (United States)

    Faini, Francesca; Labbé, Cecilia; Torres, René; Rodilla, Jesús M; Silva, Lucía; Delle Monache, Franco

    2007-12-01

    Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts.

  12. Diorganotin(IV) Complexes with Methionine Methyl Ester. Equilibria ...

    African Journals Online (AJOL)

    IV) (DBT) and diphenyltin(IV) (DPT) was investigated at 25 °C and 0.1 mol dm–3 ionic strength in water for dimethyltin(IV) and in 50 % dioxane–water mixture for dibutyltin(IV) and diphenyltin(IV). Methionine methyl ester forms1:1 and 1:2 ...

  13. FEL induced molecular operation on cultured fibroblast and cholesterol ester

    International Nuclear Information System (INIS)

    Awazu, Kunio; Ogino, Seiji; Nishimura, Eiichi; Tomimasu, Takio; Yasumoto, Masato.

    1997-01-01

    Free Electron Lasers can be used to molecular operation such as the delivery of a number of molecules into cells or the separation of cholesterol ester. First, cultured NIH3T3 cells are exposed to high-intensity short pulse Free Electron Laser (FEL). The FEL is tuned to an absorption maximum wavelength, 6.1 μm, which was measured by microscopic FTIR. A fluorescence dye in the cell suspension is more absorbed into the cell with the FEL exposure due to the FEL-induced mechanical stress to the cell membrane. A quantitative fluorescence microscopy is used to determine the efficiency of delivery. Second, as a compound in a lipid cell, cholesterol ester was exposed to 5.75 μm FEL. FTIR measurement was done to evaluate the modification of the cholesterol ester. The result showed that the fluorescence intensity of sample cells were higher than that of control cells, and there was significant difference between the control and the sample group. Blebbing and the colony formation of the cells were observed for cells with mechanical stress. As for the cholesterol ester, it can be modified by the FEL irradiation. These results showed that FEL can be used as a molecular operational tool by photo-chemical and photo-mechanical interaction. (author)

  14. PROCESS FOR HYDROGENOLYSIS OF ALPHA-HYDROXY ESTERS OR ACIDS USING A HETEROGENEOUS CATALYST

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to a method for hydrogenolysis of alpha-hydroxy esters or acids, comprising reacting the alpha-hydroxy ester or acid in the presence of a heterogeneous catalyst. The present invention also relates to a method for producing propionic acid ester, and the use of any...

  15. 21 CFR 573.640 - Methyl esters of higher fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methyl esters of higher fatty acids. 573.640... ANIMALS Food Additive Listing § 573.640 Methyl esters of higher fatty acids. The food additive methyl esters of higher fatty acids may be safely used in animal feeds in accordance with the following...

  16. 40 CFR 721.3800 - Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

    Science.gov (United States)

    2010-07-01

    ... polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3800 Section 721.3800... Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a... generically as formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

  17. Origin of estradiol fatty acid esters in human ovarian follicular fluid.

    Science.gov (United States)

    Pahuja, S L; Kim, A H; Lee, G; Hochberg, R B

    1995-03-01

    The estradiol fatty acid esters are the most potent of the naturally occurring steroidal estrogens. These esters are present predominantly in fat, where they are sequestered until they are hydrolyzed by esterases. Thus they act as a preformed reservoir of estradiol. We have previously shown that ovarian follicular fluid from patients undergoing gonadotropin stimulation contains very high amounts of estradiol fatty acid esters (approximately 10(-7) M). The source of these esters is unknown. They can be formed by esterification of estradiol in the follicular fluid by lecithin:cholesterol acyltransferase (LCAT), or in the ovary by an acyl coenzyme A:acyltransferase. In order to determine which of these enzymatic processes is the source of the estradiol esters in the follicular fluid, we incubated [3H]estradiol with follicular fluid and cells isolated from human ovarian follicular fluid and characterized the fatty acid composition of the [3H]estradiol esters biosynthesized in each. In addition, we characterized the endogenous estradiol fatty acid esters in the follicular fluid and compared them to the biosynthetic esters. The fatty acid composition of the endogenous esters was different than those synthesized by the cellular acyl coenzyme A:acyltransferase, and the same as the esters synthesized by LCAT, demonstrating that the esters are produced in situ in the follicular fluid. Although the role of these estradiol esters in the ovary is not known, given their remarkable estrogenic potency it is highly probable that they have an important physiological role.

  18. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 178.3600... SANITIZERS Certain Adjuvants and Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester identified in § 172.816(a) of this chapter may be safely used as a processing...

  19. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 172.816 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is the...

  20. Two-generation reproductive toxicity study of plant stanol esters in rats

    NARCIS (Netherlands)

    Whittaker, M.H.; Frankos, V.H.; Wolterbeek, A.P.M.; Waalkens-Berendsen, D.H.

    1999-01-01

    Plant stanol esters are intended for use as an ingredient in food to reduce the absorption of cholesterol from the gastrointestinal tract. Consumption of plant stanol esters has a demonstrated diet-derived public health benefit, as shown by numerous clinical studies. Plant stanol esters are

  1. Encapsulating fatty acid esters of bioactive compounds in starch

    Science.gov (United States)

    Lay Ma, Ursula Vanesa

    Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols

  2. Formulation development and optimization of palm kernel oil esters-based nanoemulsions containing sodium diclofenac.

    Science.gov (United States)

    Rezaee, Malahat; Basri, Mahiran; Rahman, Raja Noor Zaliha Raja Abdul; Salleh, Abu Bakar; Chaibakhsh, Naz; Karjiban, Roghayeh Abedi

    2014-01-01

    Response surface methodology was employed to study the effect of formulation composition variables, water content (60%-80%, w/w) and oil and surfactant (O/S) ratio (0.17-1.33), as well as high-shear emulsification conditions, mixing rate (300-3,000 rpm) and mixing time (5-30 minutes) on the properties of sodium diclofenac-loaded palm kernel oil esters-nanoemulsions. The two response variables were droplet size and viscosity. Optimization of the conditions according to the four variables was performed for preparation of the nanoemulsions with the minimum values of particle size and viscosity. The results showed that the experimental data could be sufficiently fitted into a third-order polynomial model with multiple regression coefficients (R(2) ) of 0.938 and 0.994 for the particle size and viscosity, respectively. Water content, O/S ratio and mixing time, quadrics of all independent variables, interaction between O/S ratio and mixing rate and between mixing time and rate, as well as cubic term of water content had a significant effect (Pdiclofenac nanoemulsions were predicted to be: 71.36% water content; 0.69 O/S ratio; 950 rpm mixing rate, and 5 minute mixing time. The optimized formulation showed good storage stability in different temperatures.

  3. Fully Biodegradable Biocomposites with High Chicken Feather Content

    Directory of Open Access Journals (Sweden)

    Ibon Aranberri

    2017-11-01

    Full Text Available The aim of this work was to develop new biodegradable polymeric materials with high loadings of chicken feather (CF. In this study, the effect of CF concentration and the type of biodegradable matrix on the physical, mechanical and thermal properties of the biocomposites was investigated. The selected biopolymers were polylactic acid (PLA, polybutyrate adipate terephthalate (PBAT and a PLA/thermoplastic copolyester blend. The studied biocomposites were manufactured with a torque rheometer having a CF content of 50 and 60 wt %. Due to the low tensile strength of CFs, the resulting materials were penalized in terms of mechanical properties. However, high-loading CF biocomposites resulted in lightweight and thermal-insulating materials when compared with neat bioplastics. Additionally, the adhesion between CFs and the PLA matrix was also investigated and a significant improvement of the wettability of the feathers was obtained with the alkali treatment of the CFs and the addition of a plasticizer like polyethylene glycol (PEG. Considering all the properties, these 100% fully biodegradable biocomposites could be adequate for panel components, flooring or building materials as an alternative to wood–plastic composites, contributing to the valorisation of chicken feather waste as a renewable material.

  4. Synthesis of thermoplastic poly(ester-olefin elastomers

    Directory of Open Access Journals (Sweden)

    Tanasijević Branka

    2004-01-01

    Full Text Available A series of thermoplastic poly(ester-olefin elastomers, based on poly(ethylene-stat-butylene, HO-PEB-OH, as the soft segment and poly (butylene terephthalate, PBT, as the hard segment, were synthesized by a catalyzed transesterification reaction in solution. The incorporation of soft hydrogenated poly(butadiene segments into the copolyester backbone was accomplished by the polycondensation of α, ω-dihydroxyl telechelic HO-PEB-OH, (PEB Mn = 3092 g/mol with 1,4-butanediol (BD and dimethyl terephthalate (DMT in the presence of a 50 wt-% high boiling solvent i.e., 1,2,4-trichlorobenzene. The molar ratio of the starting comonomers was selected to result in a constant hard to soft weight ratio of 60:40. The synthesis was optimized in terms of both the concentration of catalyst, tetra-n-butyl-titanate (Ti(OBu4, and stabilizer, N,N'-diphenyl-p-phenylenediamine (DPPD, as well as the reaction time. It was found that the optimal catalyst concentration (Ti(OBu4 for the synthesis of these thermoplastic elastomers was 1.0 mmol/mol ester and the optimal DPPD concentration was 1.0 wt-%. The extent of the reaction was followed by measuring the inherent viscosity of the reaction mixture. The effectiveness of the incorporation of the soft segments into the copolymer chains was proved by Soxhlet extraction with chloroform. The molecular structures, composition and the size of the synthesized poly(ester-butylenes were verified by 1H NMR spectroscopy, viscometry of dilute solutions and the complex dynamic melt viscosity. The thermal properties of poly(ester-olefins were investigated by differential scanning calorimetry (DSC. The degree of crystallinity was also determined by DSC. The thermal and thermo-oxidative stability were investigated by thermogravimetric analysis (TGA. The rheological properties of poly(ester-olefins were investigated by dynamic mechanical spectroscopy in the melt and solid state.

  5. Avaliação citométrica dos adipócitos localizados no tecido subcutâneo da parede anterior do abdome após infiltração percutânea de CO2

    Directory of Open Access Journals (Sweden)

    Célia Sampaio Costa

    Full Text Available OBJETIVO: Avaliar os efeitos da infiltração de dióxido de carbono em adipócitos presentes na parede abdominal. MÉTODOS: Quinze voluntárias foram submetidas a sessões de infusão de CO2 durante três semanas consecutivas (duas sessões por semana com intervalos de dois a três dias entre cada sessão. O volume de gás carbônico infundido por sessão, em pontos previamente demarcados, foi sempre calculado com base na superfície da área a ser tratada, com volume infundido fixo de 250 mL/100cm² de superfície tratada. Os pontos de infiltração foram demarcados respeitando-se o limite eqüidistante 2cm entre eles. Em cada ponto se injetou 10mL, por sessão, com fluxo de 80mL/min. Foram colhidos fragmentos de tecido celular subcutâneo da parede abdominal anterior antes e após o tratamento. O número e as alterações histomorfológicas dos adipócitos (diâmetro médio, perímetro, comprimento, largura e número de adipócitos por campos de observação foram mensurados por citometria computadorizada. Os resultados foram analisados com o teste t de Student pareado, adotando-se nível de significância de 5% (p<0,05. RESULTADOS: Encontrou-se redução significativa no número de adipócitos da parede abdominal e na área, diâmetro, perímetro, comprimento e largura após o uso da hipercapnia (p=0,0001. CONCLUSÃO: A infiltração percutânea de CO2 reduz a população e modifica a morfologia dos adipócitos presentes na parede abdominal anterior.

  6. Poly(ester amide-Poly(ethylene oxide Graft Copolymers: Towards Micellar Drug Delivery Vehicles

    Directory of Open Access Journals (Sweden)

    Gregory J. Zilinskas

    2012-01-01

    Full Text Available Micelles formed from amphiphilic copolymers are promising materials for the delivery of drug molecules, potentially leading to enhanced biological properties and efficacy. In this work, new poly(ester amide-poly(ethylene oxide (PEA-PEO graft copolymers were synthesized and their assembly into micelles in aqueous solution was investigated. It was possible to tune the sizes of the micelles by varying the PEO content of the polymers and the method of micelle preparation. Under optimized conditions, it was possible to obtain micelles with diameters less than 100 nm as measured by dynamic light scattering and transmission electron microscopy. These micelles were demonstrated to encapsulate and release a model drug, Nile Red, and were nontoxic to HeLa cells as measured by an MTT assay. Overall, the properties of these micelles suggest that they are promising new materials for drug delivery systems.

  7. Catalytic effect of carbon nanotubes on polymerization of cyanate ester resins

    Directory of Open Access Journals (Sweden)

    2009-08-01

    Full Text Available Kinetic peculiarities of polycyclotrimerization process of dicyanate ester of bisphenol A (DCBA in the presence of multi-walled carbon nanotubes (MWCNTs have been investigated using Fourier Transform Infrared Spectroscopy (FTIR spectroscopy technique. It has been found that even very small amounts of MWCNTs (0.01–0.1 wt% catalyze the reaction of polycyclotrimerization of DCBA leading to formation of polycyanurate network (PCN/MWCNTs nanocomposite. However, some decrease in final degree of conversion for nanocomposites compared to the neat PCN within the temperature/time schedule used was observed. The kinetic rate constants increased with addition of MWCNTs and energies of activation were found to be significantly decreased even at low contents of MWCNTs.

  8. Comparison of GC stationary phases for the separation of fatty acid methyl esters in biodiesel fuels.

    Science.gov (United States)

    Goding, Julian C; Ragon, Dorisanne Y; O'Connor, Jack B; Boehm, Sarah J; Hupp, Amber M

    2013-07-01

    The fatty acid methyl ester (FAME) content of biodiesel fuels has traditionally been determined using gas chromatography with a polar stationary phase. In this study, a direct comparison of the separation of FAMEs present in various biodiesel samples on three polar stationary phases and one moderately polar stationary phase (with comparable column dimensions) was performed. Retention on each column was based on solubility in and polarity of the phase. Quantitative metrics describing the resolution of important FAME pairs indicate high resolution on all polar columns, yet the best resolution, particularly of geometric isomers, is achieved on the cyanopropyl column. In addition, the separation of four C18 monounsaturated isomers was optimized and the elution order determined on each column. FAME composition of various biodiesel fuel types was determined on each column to illustrate (1) chemical differences in biodiesels produced from different feedstocks and (2) chemical similarities in biodiesels of the same feedstock type produced in different locations and harvest seasons.

  9. Synthesis and Characterization of Novel Polyurethanes Based on Vegetable Oils Amide and Ester Polyols

    Directory of Open Access Journals (Sweden)

    Vladimir YAKUSHIN

    2014-09-01

    Full Text Available Amide and ester type polyols were synthesized from rapeseed, sunflower and castor oils, and two types of ethanolamine (diethanolamine and triethanolamine at different molar ratio. Poly(urethane amides and polyester urethanes based on the synthesized polyols were prepared. The effect of the chemical structure of the obtained polyurethanes on density, glass transition temperature, thermal stability and mechanical properties was investigated. The influence of the content of OH groups in the synthesized polyols on the specified characteristics was estimated. It has been found that poly(urethane amides have better mechanical characteristics, but their thermal stability is lower than that of polyester urethanes. The chemical structure of the synthesized polyols and polyurethanes is qualitatively confirmed by IR-spectroscopy data. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4532

  10. Toughened cyanate ester alloys via reaction-induced phase separation; Hanno yuhatsugataso bunkai ni yoru taishogekisei cyanate ester alloy

    Energy Technology Data Exchange (ETDEWEB)

    Hirohata, T.; Kuroda, M.; Nishimura, A. [Sumitomo Electric Industries, Ltd., Osaka (Japan); Inoue, T. [Tokyo Institute of Technology, Tokyo (Japan)

    1998-03-15

    For the purpose of toughening the matrices of fiber-reinforced plastics (FRPs), the effect of thermosetting/thermoplastic polymer alloys based on cyanate ester alloys is investigated. In the experiment, materials are heated and then allowed to set, which are mixtures of 87.0-43.5wt% of cyanate ester resin, 0-43.5wt% of epoxy resin, and 13.0wt% of soluble polyimide. FRP properties are examined by measuring the after-shock compressive strength, flexural elasticity and flaxural strength, and by performing morphology observation. It is then found that a cyanate ester/soluble polyimide system forms a polymer alloy with phase separation, that its glass transition temperature does not drop, and that the rupture strength is increased approximately twice. A carbon fiber-reinforced plastic (CFRP) incorporating this system is twice higher in after-shock compression strength than a CFRP incorporating a cyanate ester. The system withstands high temperatures, retaining at 200degC approximately 90% of the elastic modulus it exhibits at room temperature. 15 refs., 16 figs.

  11. Valimiskaotuse haavu raviva Rahvaliidu ajutine juht Ester Tuiksoo : "Meil on tugev küünarnukitunne" / Ester Tuiksoo

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Ilmunud ka: Severnoje Poberezhje, 28. märts 2007, lk. 2. Delfi lugejate küsimustele vastab Rahvaliidu ajutine juht ja lahkuva valitsuse põllumajandusminister Ester Tuiksoo, kellelt päriti nii erakonna maine taastamise, eesti toidu kui ka jopede jagamise kohta

  12. Effects of mixing technologies on continuous methyl ester production: Comparison of using plug flow, static mixer, and ultrasound clamp

    International Nuclear Information System (INIS)

    Somnuk, Krit; Prasit, Tanongsak; Prateepchaikul, Gumpon

    2017-01-01

    Highlights: • Four types of continuous reactors were compared with methyl ester conversion. • Plug flow, static mixer, ultrasound clamp, SM with ultrasound reactors were tested. • The 16 × 400 W ultrasound clamps were operated at 20 kHz frequency for US reactor. • The US reactor was clearly superior over the other types of continuous reactor. • The US reactor was the most effective alternative with short reactor length. - Abstract: Four types of continuous reactors, namely plug flow reactor (PF), static mixer reactor (SM), ultrasound clamp on tubular reactor (US), and static mixer combined with ultrasound (SM/US) were compared for their purities of methyl ester in biodiesel production from refined palm oil (RPO). The reactor conditions were: KOH 4, 6, 8, 10, and 12 g L −1 , methanol content 20 vol.%, and under 20 L h −1 RPO flow rate at 60 °C temperature. The highest purity of methyl esters: 81.99 wt.% for PF, 95.70 wt.% for SM, 98.98 wt.% for US, and 97.67 wt.% for SM/US, were achieved with 900 mm, 900 mm, 700 mm, and 900 mm reactor lengths respectively, and 12 g L −1 of KOH was used in all cases. The 16 × 400 W ultrasound clamp was operated at 20 kHz frequency, and among short length reactors the US case was more effective than PF, SM, or SM/US. Moreover, ester purity from the US reactor was slightly decreased by the lowest 4 g L −1 KOH. The US reactor was clearly superior over the other types of continuous reactor, and had the potential to reduce KOH consumption by sonochemical effects on the base-catalyzed transesterification reaction.

  13. Production of ethyl ester from crude palm oil by two-step reaction using continuous microwave system

    Directory of Open Access Journals (Sweden)

    Sukritthira Ratanawilai

    2011-02-01

    Full Text Available The esterification of free fatty acids (FFA in vegetable oils with alcohol using an acid catalyst is a promising methodto convert FFA into valuable ester and obtain a FFA-free oil that can be further transesterified using alkali bases. In thiswork, the direct esterification reaction of FFA in crude palm oil to ethyl ester by continuous microwave was studied and theeffects of the main variables involved in the process, amount of catalyst, reaction time and the molar ratio oil/ alcohol, wereanalyzed. The optimum condition for the continuous esterification process was carried out with a molar ratio of oil to ethanol1:6, using 1.25%wt of H2SO4/oil as a catalyst, microwave power of 78 W and a reaction time 90 min. This esterification processshows that the amount of FFA was reduced from 7.5%wt to values around 1.4 %wt. Similar results were obtained followingconventional heating at 70°C, but only after a reaction time of 240 min. The esterified crude palm oil is suitable to perform thetransesterification process. Transesterification of the esterified palm oil has been accomplished with a molar ratio of oil toethanol of 1:8.5, 2.5%wt of KOH as a catalyst, a microwave power of 78 W, and a reaction time of 7 min. In addition, theproblem of glycerin separation was solved by mixing 10%wt of pure glycerin into the ethyl ester to induce the glycerin fromthe reaction to separated. This two-step esterification and transesterification process provided a yield of 78%wt with anester content of 97.4%wt. The final ethyl ester product met with the specifications stipulated by ASTM D6751-02.

  14. Biodegradation of poly(lactic acid, poly(hydroxybutyrate-co-hydroxyvalerate, poly(butylene succinate and poly(butylene adipate-co-terephthalate under anaerobic and oxygen limited thermophilic conditions

    Directory of Open Access Journals (Sweden)

    Jutakan Boonmee

    2016-01-01

    Full Text Available In order to study the biodegradation behavior of biodegradable plastics in landfill conditions, four types of biodegradable plastics including poly(lactic acid (PLA, poly(hydroxybutyrate-co-hydroxyvalerate (PHBV, poly(butylene succinate (PBS, and poly(butylene adipate-co-terephthalate (PBAT were tested by burying in sludge mixed soil medium under anaerobic and oxygen limited conditions. The experiments were operated at 52 ± 2ºC in dark conditions according to ISO15985. The degree of biodegradation after 75 days was investigated by weight loss determination, visual examination, and surface appearance by scanning electronic microscopy (SEM. Under both anaerobic and oxygen limited conditions, the complete degradation (100% weight loss was found only in PHBV after 75 days. The plastic degradations were ranked in the order of PHBV> PLA> PBS> PBAT. The percentage of weight losses were significantly different at p ≤ 0.05. However, for all studied plastics, the degradation under anaerobic and oxygen limited conditions did not significantly different at 95% confidence.

  15. Role of special interfacial area in controlling properties of immiscible blends of biodegradable polylactide and poly[(butylene succinate)-co-adipate

    CSIR Research Space (South Africa)

    Ojijo, Vincent O

    2012-12-01

    Full Text Available by scanning electron microscopy (SEM). SEM micrographs showed that PLA-rich blends had smaller droplet sizes when compared to the PBSArich blends, which got smaller with the reduction in PBSA content due to the differences in their melt viscosities...

  16. Lipase catalyzed ester synthesis for food processing industries

    Directory of Open Access Journals (Sweden)

    Aravindan Rajendran

    2009-02-01

    Full Text Available Lipases are one of the most important industrial biocatalyst which catalyzes the hydrolysis of lipids. It can also reverse the reaction at minimum water activity. Because of this pliable nature, it is widely exploited to catalyze the diverse bioconversion reactions, such as hydrolysis, esterification, interesterification, alcoholysis, acidolysis and aminolysis. The property to synthesize the esters from the fatty acids and glycerol promotes its use in various ester synthesis. The esters synthesized by lipase finds applications in numerous fields such as biodiesel production, resolution of the recemic drugs, fat and lipid modification, flavour synthesis, synthesis of enantiopure pharmaceuticals and nutraceuticals. It plays a crucial role in the food processing industries since the process is unaffected by the unwanted side products. Lipase modifications such as the surfactant coating, molecular imprinting to suit for the non-aqueous ester synthesis have also been reported. This review deals with lipase catalyzed ester synthesis, esterification strategies, optimum conditions and their applications in food processing industries.Lipases são catalizadores industriais dos mais importantes, os quais catalizam a hidrólise de lipídeos. Também podem reverter a reação a um mínimo de atividade de água. Devido sua natureza flexível, é amplamente explorada para catalizar uma diversidade de reações de bioconversão como hidrólise, esterificação, interesterificação, alcoólise, acidólise e aminólise. A propriedade de síntese de esteres a partir de ácidos graxos e glicerol promoveu seu uso em várias sínteses de esteres. Os esteres sintetizados por lipases encontram aplicação em numerosos campos como a produção de biodiesel, resolução de drogas racêmicas, modificação de gorduras e lipídios, sintese de aromas, síntese de produtos farmacêuticos enantiopuro e nutracêuticos. As lipases possuem um papel crucial nas indústrias de

  17. Advertising Content

    OpenAIRE

    Simon P. Anderson; Régis Renault

    2002-01-01

    Empirical evidence suggests that most advertisements contain little direct informa- tion. Many do not mention prices. We analyze a firm'ss choice of advertising content and the information disclosed to consumers. A firm advertises only product informa- tion, price information, or both; and prefers to convey only limited product information if possible. Extending the "persuasion" game, we show that quality information takes precedence over price information and horizontal product information.T...

  18. Synthesis of methyl ester sulphonate by sulfonation of soybean oil methyl ester for chemical flooding application

    International Nuclear Information System (INIS)

    Richie Adi Putra; Renisa Ismayanti; Agam Duma Kalista W

    2018-01-01

    This research has accomplished the synthesis of Surfactant Methyl Ester Sulphonate from Methyl Soyate and Sodium Bisulfite as sulfonating agent. The Steps of the synthesis were reaction, purification, neutralization, and separation. The reaction done by several variated condition such as Reaction Temperature (100, 110, 120)°C, Reaction time (210, 270, 330)minute, and the mole ratio between Methyl Soyate and NaHSO 3 (1:1, 1:1.5, 1:2) with 1.5 % of Al 2 O 3 as catalyst of sulfonation reaction. The purification process was conducted at 55 °C and 60 minute by adding Methanol 35 % v/v. The neutralization done was conducted by 20 % of NaOH until pH 6-8. And the rest of the methanol are separated from MES using rotary evaporator. MES which is pass the compatibility Test is MES at the condition of reaction (100 °C, 210 minute and 1 : 2 mole ratio).This MES has tested by FT - IR to see the existence of the Sulphonate group.The FT-IR test result has shown the existence of the Sulphonate group at wave length between 1000 until 1300 cm -1 . Which is the highest peak at 1176 cm-1. From the qualitative test above, then the MES performed by IFT Test with light oil of X- field as comparison. The IFT results has shown a decrease of the interfacial tensions between 12,000 ppm of brine water and the light oil with addition of 0.3 % (v/v) MES, from 3.36 dyne/cm 2 to 1.54 dyne/cm 2 . (author)

  19. [Development of the determination methods of fatty acid esters of chloropropanediols in fat-rich foods].

    Science.gov (United States)

    Yan, Xiaobo; Wu, Shaoming; Li, Nan; Lü, Huadong; Fu, Wusheng

    2013-02-01

    Fatty acid esters of chloropropanediols are a kinds of newly emerged food contaminants, especially 3-monochloropropane-1,2-diol (3-MCPD) esters that have been detected in many foodstuffs such as infant formula and edible oils at relatively high levels. Based on the Tolerable Dose Intake (TDI) of 3-MCPD, the intake of 3-MCPD from 3-MCPD esters may cause the health risk to human beings. The researches for the analysis of 3-MCPD esters have been carried out in some institutes abroad, but there were only a few in China. This paper reviews the methods for the determination of 3-MCPD esters in fat-rich foods, including the extraction, hydrolysis, the derivatization of 3-MCPD esters, the total amount of 3-MCPD esters and the amounts of monoesters and diesters of 3-MCPD.

  20. Influences of hyperbranched poly(amide-ester) on the properties of poly(butylene succinate)

    International Nuclear Information System (INIS)

    Run, Mingtao; Wang, Jian; Yao, Meng; Guo, Lijie; Wang, Hai-jun; Ba, Xinwu

    2013-01-01

    The polymer blends of hyperbranched poly(amide-ester) and poly(butylene succinate) (HBP/PBS) were prepared by melt-blending method. The molecular interaction within the blends, phase morphology, crystal morphology, mechanical, rheological and dynamic mechanical properties were investigated by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), tensile machine, polarized optical microscopy, rotational rheometer and dynamic mechanical analyzer (DMA), respectively. The results suggest that PBS and HBP have a certain compatibility at amorphous state. A certain number of H-bonding was detected between PBS and HBP phases and it influences the material properties. HBP not only serves partially as a nucleating agent for the crystallization of PBS but also plays a role of plasticizer for the rheology of PBS. The glass transition temperatures of the blends slightly decrease with increasing HBP content. The proper amount of HBP (4–6%) has a reinforcement effect on the PBS matrix at glassy state. However, the blend with 10%HBP content has an improved impact strength mainly due to the plasticization effect or H-bonding effect of HBP on PBS matrix. The storage modulus is increased with increasing HBP contents, and the loss modulus is much smaller than the storage modulus in each blend at glassy state. At rubbery state the storage modulus of different samples is independent of HBP content. The complex viscosity of the melt decreases with increasing HBP content; however, the blend with 10%HBP is a special sample because of its abnormal larger complex viscosity at low shear frequencies. In addition, the melt’s elasticity behavior increases slightly with increasing HBP content. - Highlights: ► H-bonding was detected between PBS and HBP phases by FTIR. ► HBP serves partly as a nucleating agent for the crystallization of PBS. ► HBP plays a role of plasticizer for PBS. ► The blend with 10%HBP has abnormal larger complex viscosity

  1. Assessment of process variables on the use of macauba pulp oil as feedstock for the continuous production of ethyl esters under pressurized conditions

    Directory of Open Access Journals (Sweden)

    T. A. da S. Colonelli

    Full Text Available ABSTRACT This study evaluated the potential of macauba pulp oil (MPO as a feedstock for continuous ester production using ethanol under pressurized conditions. Experiments were performed in order to obtain data for the effect of process variables on ethyl ester (FAEE and free fatty acid (FFA conversion in a catalyst-free process. From the results, it appears that the MPO to ethanol mass ratio and the pressure were the variables with more favorable effect on the evaluated response variables. The addition of n-hexane caused an increase in the production of esters; however, this had a negative effect on FFA conversion. The addition of water was unfavorable for oil processing with high acidity. In this process, esterification and transesterification occur simultaneously, and the high FFA content in MPO provides high yields (85 wt% of esters; 93% FFA conversion at low temperature, since the esterification reaction rate is higher than the transesterification. The decomposition of fatty acids was evaluated and levels <5% were observed under the evaluated experimental conditions.

  2. Synthesis of fatty acid methyl ester from crude jatropha (Jatropha curcas Linnaeus) oil using aluminium oxide modified Mg-Zn heterogeneous catalyst.

    Science.gov (United States)

    Olutoye, M A; Hameed, B H

    2011-06-01

    The synthesis of fatty acid methyl esters (FAME) as a substitute to petroleum diesel was investigated in this study from crude jatropha oil (CJO), a non-edible, low-cost alternative feedstock, using aluminium modified heterogeneous basic oxide (Mg-Zn) catalyst. The transesterification reaction with methanol to methyl esters yielded 94% in 6h with methanol-oil ratio of 11:1, catalyst loading of 8.68 wt.% at 182°C and the properties of CJO fuel produced were determine and found to be comparable to the standards according to ASTM. In the range of experimental parameters investigated, it showed that the catalyst is selective to production of methyl esters from oil with high free fatty acid (FFA) and water content of 7.23% and 3.28%, respectively in a single stage process. Thus, jatropha oil is a promising feedstock for methyl ester production and large scale cultivation will help to reduce the product cost. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Plasma application for detoxification of Jatropha phorbol esters

    International Nuclear Information System (INIS)

    Kongmany, S; Matsuura, H; Furuta, M; Okuda, S; Imamura, K; Maeda, Y

    2013-01-01

    Atmospheric pressure non-thermal dielectric barrier discharge (DBD) plasma generated by helium gas at high voltage and input power of about 50 W was first applied to detoxification of Jatropha curcas phorbol esters (J. PEs) as well as standard phorbol ester (4β-12-O-tetradecanoyl phorbol-13-acetate, TPA) in water and methanol. Plasma irradiation on the solution sample was conducted for 15 min. In aqueous solution, only 16% of TPA was degraded and complete degradation of J. PEs was observed. On the contrary, complete degradation of both TPA and J. PEs in methanol was achieved by the same plasma irradiation condition. Hydroxyl radical (.OH) generated by plasma irradiation of the solution is expected as the main radical inducing the degradation of PEs.

  4. The sonochemical arylation of malonic esters mediated by manganese triacetate.

    Science.gov (United States)

    Meciarova, M; Toma, S; Luche, J L

    2001-04-01

    The intermolecular arylation of malonate esters in acetic acid solution in the presence of manganese(III) triacetate is known to proceed via an Electron Transfer mechanism. Under sonication, this reaction undergoes only minor changes. In contrast, the intramolecular reaction of dimethyl alpha-(3-phenylpropyl)malonate provides a new case of sonochemical switching, with the formation of compounds 7-9, while conventional thermal conditions generate only the bicyclic compound 6. Reactions using the more powerful oxidant, cerium ammonium nitrate are governed by the formation of the nitrate ester 11. Compounds 7-9 are isolated in yields lower than with MnTA, and in proportions depending on the conditions, thermal or sonochemical.

  5. Fatty acid methyl esters production: chemical process variables

    Directory of Open Access Journals (Sweden)

    Paulo César Narváez Rincón

    2004-05-01

    Full Text Available The advantages of fatty acid methyl esters as basic oleochemicals over fatty acids, the seventies world energy crisis and the use of those oleochemicals as fuels, have increased research interest on fats and oils trans-esterification. In this document, a review about basic aspects, uses, process variables and problems associated to the production process of fatty acid methyl esters is presented. A global view of recent researches, most of them focused in finding a new catalyst with same activity as the alcohol-soluble hydroxides (NaOH, KOH, and suitable to be used in transforming fats and oils with high levels of free fatty acids and water avoiding separation problems and reducing process costs, is also discussed.

  6. Organising pneumonia associated with fumaric acid ester treatment for psoriasis.

    Science.gov (United States)

    Deegan, Alexander Paul; Kirby, Brian; Rogers, Sarah; Crotty, Tom Bernard; McDonnell, Timonthy John

    2010-10-01

      We present the case of a 49-year old male who presented with dyspnoea, cough, weight loss, night sweats and general malaise. He had been on treatment with oral fumaric acid esters (FAE, Fumaderm®; Biogen Idec GmbH, Ismaning, Germany) for 6 months.   Report of a case.   His chest X-ray showed patchy infiltrates in the left upper lobe which failed to resolve under empiric antibiotic therapy. A computed tomography of thorax revealed bilateral, mostly peripheral foci of consolidation with air bronchograms. Transbronchial biopsies showed a pattern of organising pneumonia (OP).   Therapy with oral prednisolone (40 mg/day) resulted in a rapid clinical and radiological improvement. An association of FAE and OP has not previously been reported. Please cite this paper as: Deegan AP, Kirby B, Rogers S, Crotty TB and McDonnell TJ. Organising pneumonia associated with fumaric acid ester treatment for psoriasis. © 2010 Blackwell Publishing Ltd.

  7. Organising pneumonia associated with fumaric acid ester treatment for psoriasis.

    LENUS (Irish Health Repository)

    Deegan, Alexander Paul

    2012-02-01

    INTRODUCTION: We present the case of a 49-year old male who presented with dyspnoea, cough, weight loss, night sweats and general malaise. He had been on treatment with oral fumaric acid esters (FAE, Fumaderm(R); Biogen Idec GmbH, Ismaning, Germany) for 6 months. METHODS: Report of a case. RESULTS: His chest X-ray showed patchy infiltrates in the left upper lobe which failed to resolve under empiric antibiotic therapy. A computed tomography of thorax revealed bilateral, mostly peripheral foci of consolidation with air bronchograms. Transbronchial biopsies showed a pattern of organising pneumonia (OP). CONCLUSIONS: Therapy with oral prednisolone (40 mg\\/day) resulted in a rapid clinical and radiological improvement. An association of FAE and OP has not previously been reported. Please cite this paper as: Deegan AP, Kirby B, Rogers S, Crotty TB and McDonnell TJ. Organising pneumonia associated with fumaric acid ester treatment for psoriasis.

  8. Degradation Mechanisms of Poly(ester urethane) Elastomer

    Energy Technology Data Exchange (ETDEWEB)

    Edgar, Alexander S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-30

    This report describes literature regarding the degradation mechanisms associated with a poly(ester urethane) block copolymer, Estane® 5703 (Estane), used in conjunction with Nitroplasticizer (NP), and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane, also known as high molecular weight explosive (HMX) to produce polymer bonded explosive PBX 9501. Two principal degradation mechanisms are reported: NO2 oxidative reaction with the urethane linkage resulting in crosslinking and chain scission events, and acid catalyzed hydrolysis of the ester linkage. This report details future work regarding this PBX support system, to be conducted in late 2017 and 2018 at Engineered Materials Group (MST-7), Materials Science and Technology Division, Los Alamos National Laboratory. This is the first of a series of three reports on the degradation processes and trends of the support materials of PBX 9501.

  9. Study on the Novel Dicyanate Ester Resin Containing Naphthalene Unit

    Institute of Scientific and Technical Information of China (English)

    Hong Qiang YAN; Hong Yun PENG; Li JI; Guo Rong QI

    2004-01-01

    The novel dicyanate ester resin containing naphthalene unit (DNCY) was synthesized, and characterized by FT-IR, 1H-NMR, 13C-NMR and elemental analysis (EA).The thermal properties of DNCY resin was studied by thermal degradation analysis at a heating rate of 10 (C /min-1 in N2 and air. The DNCY resin exhibited better thermal and thermal-oxidative stability than bisphenol A dicyanate (BACY) resin.

  10. Synthesis of new radiotracers based of Ethyl Ester

    International Nuclear Information System (INIS)

    Trabelsi, Donia

    2008-01-01

    The in vivo study of a biochemical or physiological process requires the synthesis of specific radiotracers but also the targeting of these compounds so that they can reach their target tissue. Methodologies original synthesis associated with radioisotopes used, the quantities and chemical forms often have to be available developed. The chemistry of metal complexes booming, we were able to use the ethyl ester combined with technetium, forming a stable radiotracer. Finally, a counting of radioactivity in different rat's organs completed our study. (Author)

  11. Development of chemical process for synthesis of polyunsaturated esters

    OpenAIRE

    Vera LÃcia Viana do Nascimento

    2014-01-01

    This work aimed to develop refining processes, chemical alcoholysis followed by separation of fatty acids using the complexation with urea technique for the synthesis of poly-unsaturated esters from waste of fish oils. The special crude fish oil was purchased from Company Campestre - SÃo Paulo. Initially this oil has undergone a process of physical and chemical refining. From the refined oil, an alcoholysis process was carried out to obtain the mixture of free fatty acids. From the hydrolyzed...

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

    Science.gov (United States)

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

    2014-11-01

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

  13. Catalytic Ester and Amide to Amine Interconversion: Nickel-Catalyzed Decarbonylative Amination of Esters and Amides by C−O and C−C Bond Activation

    KAUST Repository

    Yue, Huifeng

    2017-03-15

    An efficient nickel-catalyzed decarbonylative amination reaction of aryl and heteroaryl esters has been achieved for the first time. The new amination protocol allows the direct interconversion of esters and amides into the corresponding amines and represents a good alternative to classical rearrangements as well as cross coupling reactions.

  14. Catalytic Ester and Amide to Amine Interconversion: Nickel-Catalyzed Decarbonylative Amination of Esters and Amides by C−O and C−C Bond Activation

    KAUST Repository

    Yue, Huifeng; Guo, Lin; Liao, Hsuan-Hung; Cai, Yunfei; Zhu, Chen; Rueping, Magnus

    2017-01-01

    An efficient nickel-catalyzed decarbonylative amination reaction of aryl and heteroaryl esters has been achieved for the first time. The new amination protocol allows the direct interconversion of esters and amides into the corresponding amines and represents a good alternative to classical rearrangements as well as cross coupling reactions.

  15. Scientific opinion: Risks for human health related to the presence of 3- and 2-monochloropropanediol (MCPD), and their fatty acid esters, and glycidyl fatty acid esters in food

    NARCIS (Netherlands)

    Hoogenboom, L.A.P.

    2016-01-01

    EFSA was asked to deliver a scientific opinion on free and esterified 3- and 2-monochloropropane-1,2-diol (MCPD) and glycidyl esters in food. Esters of 3- and 2-MCPD and glycidol are contaminants of processed vegetable oils; free MCPDs are formed in some processed foods. The Panel on Contaminants in

  16. Wax ester profiling of seed oil by nano-electrospray ionization tandem mass spectrometry

    Science.gov (United States)

    2013-01-01

    Background Wax esters are highly hydrophobic neutral lipids that are major constituents of the cutin and suberin layer. Moreover they have favorable properties as a commodity for industrial applications. Through transgenic expression of wax ester biosynthetic genes in oilseed crops, it is possible to achieve high level accumulation of defined wax ester compositions within the seed oil to provide a sustainable source for such high value lipids. The fatty alcohol moiety of the wax esters is formed from plant-endogenous acyl-CoAs by the action of fatty acyl reductases (FAR). In a second step the fatty alcohol is condensed with acyl-CoA by a wax synthase (WS) to form a wax ester. In order to evaluate the specificity of wax ester biosynthesis, analytical methods are needed that provide detailed wax ester profiles from complex lipid extracts. Results We present a direct infusion ESI-tandem MS method that allows the semi-quantitative determination of wax ester compositions from complex lipid mixtures covering 784 even chain molecular species. The definition of calibration prototype groups that combine wax esters according to their fragmentation behavior enables fast quantitative analysis by applying multiple reaction monitoring. This provides a tool to analyze wax layer composition or determine whether seeds accumulate a desired wax ester profile. Besides the profiling method, we provide general information on wax ester analysis by the systematic definition of wax ester prototypes according to their collision-induced dissociation spectra. We applied the developed method for wax ester profiling of the well characterized jojoba seed oil and compared the profile with wax ester-accumulating Arabidopsis thaliana expressing the wax ester biosynthetic genes MaFAR and ScWS. Conclusions We developed a fast profiling method for wax ester analysis on the molecular species level. This method is suitable to screen large numbers of transgenic plants as well as other wax ester samples

  17. Correlation for the estimation of the density of fatty acid esters fuels and its implications. A proposed Biodiesel Cetane Index.

    Science.gov (United States)

    Lapuerta, Magín; Rodríguez-Fernández, José; Armas, Octavio

    2010-09-01

    Biodiesel fuels (methyl or ethyl esters derived from vegetables oils and animal fats) are currently being used as a means to diminish the crude oil dependency and to limit the greenhouse gas emissions of the transportation sector. However, their physical properties are different from traditional fossil fuels, this making uncertain their effect on new, electronically controlled vehicles. Density is one of those properties, and its implications go even further. First, because governments are expected to boost the use of high-biodiesel content blends, but biodiesel fuels are denser than fossil ones. In consequence, their blending proportion is indirectly restricted in order not to exceed the maximum density limit established in fuel quality standards. Second, because an accurate knowledge of biodiesel density permits the estimation of other properties such as the Cetane Number, whose direct measurement is complex and presents low repeatability and low reproducibility. In this study we compile densities of methyl and ethyl esters published in literature, and proposed equations to convert them to 15 degrees C and to predict the biodiesel density based on its chain length and unsaturation degree. Both expressions were validated for a wide range of commercial biodiesel fuels. Using the latter, we define a term called Biodiesel Cetane Index, which predicts with high accuracy the Biodiesel Cetane Number. Finally, simple calculations prove that the introduction of high-biodiesel content blends in the fuel market would force the refineries to reduce the density of their fossil fuels. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  18. Neuroprotective effects of phytosterol esters against high cholesterol-induced cognitive deficits in aged rat.

    Science.gov (United States)

    Rui, Xu; Wenfang, Li; Jing, Cheng; Meng, Chen; Chengcheng, Ding; Jiqu, Xu; Shuang, Rong

    2017-03-22

    Accumulating epidemiological and experimental studies have confirmed that a high-cholesterol diet is detrimental to cognitive performance in animal models. Phytosterols, a class of naturally occurring structural components in plant foods, have been demonstrated to possess cholesterol-lowering and antioxidant effects. Phytosterol esters (PSE) are esters of phytosterol. The aim of this study was to evaluate the neuroprotective effects of PSE on cognitive deficit induced by a cholesterol-enriched diet in aged rats, and to explore their underlying mechanisms for these effects. Based on their Morris water maze performance, the latencies differed by <1.5 standard deviations (SDs) on days 3-5 of testing, 60 rats were chosen from 12-month-old female Sprague Dawley aged rats and were randomized into three groups, which were fed either a control diet, a high cholesterol diet (HCD) or a high-cholesterol diet supplemented with 2% PSE (HCD + PSE) for 6 months. In our study, we found that PSE treatment maintained the body weight balance, reduced the serum lipid levels, and improved the cognitive performance of aged rats in the Morris water maze test, as evaluated by shortened escape latencies. Importantly, histological and immunohistochemical results in the brain showed that PSE supplementation may have a neuroprotective effect that alleviates neuroinflammation in aged rats. This neuroprotective effect significantly inhibited degeneration, resulting in a significant increase in the number of pyramidal cells and an apparent decrease in the number of astrocytes compared to rats that were fed only a HCD. Furthermore, PSE improved cholinergic activities by restoring the acetylcholine (ACh) content and decreasing acetylcholinesterase (AChE) activity in the cerebral cortex, as well as by elevating choline acetyl transferase (ChAT) activity in the hippocampus and the cerebral cortex. These results suggest that PSE can play a useful role in alleviating cognitive deficit induced by a

  19. Ester-free Thiol-X Resins: New Materials with Enhanced Mechanical Behavior and Solvent Resistance.

    Science.gov (United States)

    Podgórski, Maciej; Becka, Eftalda; Chatani, Shunsuke; Claudino, Mauro; Bowman, Christopher N

    A series of thiol-Michael and radical thiol-ene network polymers were successfully prepared from ester-free as well as ester-containing monomer formulations. Polymerization reaction rates, dynamic mechanical analysis, and solvent resistance experiments were performed and compared between compositions with varied ester loading. The incorporation of ester-free alkyl thiol, vinyl sulfone and allylic monomers significantly improved the mechanical properties when compared with commercial, mercaptopropionate-based thiol-ene or thiol-Michael networks. For polymers with no hydrolytically degradable esters, glass transition temperatures (T g 's) as high as 100 °C were achieved. Importantly, solvent resistance tests demonstrated enhanced stability of ester-free formulations over PETMP-based polymers, especially in concentrated basic solutions. Kinetic analysis showed that glassy step-growth polymers are readily formed at ambient conditions with conversions reaching 80% and higher.

  20. Potential Grape-Derived Contributions to Volatile Ester Concentrations in Wine

    OpenAIRE

    Boss, Paul; Pearce, Anthony; Zhao, Yanjia; Nicholson, Emily; Dennis, Eric; Jeffery, David

    2015-01-01

    Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl est...

  1. Microbial synthesis of a branched-chain ester platform from organic waste carboxylates

    Directory of Open Access Journals (Sweden)

    Donovan S. Layton

    2016-12-01

    Full Text Available Processing of lignocellulosic biomass or organic wastes produces a plethora of chemicals such as short, linear carboxylic acids, known as carboxylates, derived from anaerobic digestion. While these carboxylates have low values and are inhibitory to microbes during fermentation, they can be biologically upgraded to high-value products. In this study, we expanded our general framework for biological upgrading of carboxylates to branched-chain esters by using three highly active alcohol acyltransferases (AATs for alcohol and acyl CoA condensation and modulating the alcohol moiety from ethanol to isobutanol in the modular chassis cell. With this framework, we demonstrated the production of an ester library comprised of 16 out of all 18 potential esters, including acetate, propionate, butanoate, pentanoate, and hexanoate esters, from the 5 linear, saturated C2-C6 carboxylic acids. Among these esters, 5 new branched-chain esters, including isobutyl acetate, isobutyl propionate, isobutyl butyrate, isobutyl pentanoate, and isobutyl hexanoate were synthesized in vivo. During 24 h in situ fermentation and extraction, one of the engineered strains, EcDL208 harnessing the SAAT of Fragaria ananassa produced ~63 mg/L of a mixture of butyl and isobutyl butyrates from glucose and butyrate co-fermentation and ~127 mg/L of a mixture of isobutyl and pentyl pentanoates from glucose and pentanoate co-fermentation, with high specificity. These butyrate and pentanoate esters are potential drop-in liquid fuels. This study provides better understanding of functional roles of AATs for microbial biosynthesis of branched-chain esters and expands the potential use of these esters as drop-in biofuels beyond their conventional flavor, fragrance, and solvent applications. Keywords: Carboxylate platform, Ester platform, Branched-chain ester, Modular cell, Biological upgrading, Organic waste, Lignocellulosic biomass, Isobutyl esters

  2. Hybrid thermosets from vinyl ester resin and acrylated epoxidized soybean oil (AESO

    Directory of Open Access Journals (Sweden)

    2011-01-01

    Full Text Available A series of hybrids composed of styrene crosslinkable vinyl ester (VE and acrylated epoxidized soybean oil (AESO were produced via free radical-induced crosslinking. The VE/AESO ratio was changed between 75/25 and 25/75 wt%. Moreover, to support phase grafting the VE/AESO = 50/50 wt% hybrid was modified with phthalic anhydride in various amounts (1, 5 and 10 wt%. The structure of the hybrid systems was investigated by dynamic mechanical thermal analysis (DMTA, differential scanning calorimetry (DSC, and atomic force microscopy (AFM. The properties of the systems were assessed by static flexural and fracture mechanical tests. The resistance to thermal degradation was inspected by thermogravimetric analysis (TGA. The results suggested that the hybrids have an interpenetrating network (IPN structure. With increasing AESO content the stiffness (modulus, strength and glass transition temperature (Tg of the hybrids decreased, whereas their ductility increased. Phthalic anhydride caused an adverse trend. Both the fracture toughness and fracture energy increased with increasing AESO content. They were less affected by adding phthalic anhydride phase couplant. Interestingly, the hybrids outperformed the parent VE and AESO in respect to resistance to thermal degradation.

  3. Evaluation of cysteine ethyl ester as efficient inducer for glutathione overproduction in Saccharomyces spp.

    Science.gov (United States)

    Lorenz, Eric; Schmacht, Maximilian; Senz, Martin

    2016-11-01

    Economical yeast based glutathione (GSH) production is a process that is influenced by several factors like raw material and production costs, biomass production and efficient biotransformation of adequate precursors into the final product GSH. Nowadays the usage of cysteine for the microbial conversion into GSH is industrial state of practice. In the following study, the potential of different inducers to increase the GSH content was evaluated by means of design of experiments methodology. Investigations were executed in three natural Saccharomyces strains, S. cerevisiae, S. bayanus and S. boulardii, in a well suited 50ml shake tube system. Results of shake tube experiments were confirmed in traditional baffled shake flasks and finally via batch cultivation in lab-scale bioreactors under controlled conditions. Comprehensive studies showed that the usage of cysteine ethyl ester (CEE) for the batch-wise biotransformation into GSH led up to a more than 2.2 times higher yield compared to cysteine as inducer. Additionally, the intracellular GSH content could be significantly increased for all strains in terms of 2.29±0.29% for cysteine to 3.65±0.23% for CEE, respectively, in bioreactors. Thus, the usage of CEE provides a highly attractive inducing strategy for the GSH overproduction. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Diversities of phthalate esters in suburban agricultural soils and wasteland soil appeared with urbanization in China

    International Nuclear Information System (INIS)

    Kong Shaofei; Ji Yaqin; Liu Lingling; Chen Li; Zhao Xueyan; Wang Jiajun; Bai Zhipeng; Sun Zengrong

    2012-01-01

    The distribution of six priority phthalic acid esters (PAEs) in suburban farmland, vegetable, orchard and wasteland soils of Tianjin were obtained with gas chromatography-mass spectrometer analysis in 2009. Results showed that total PAEs varied from 0.05 to 10.4 μg g −1 , with the median value as 0.32 μg g −1 . Di-(2-ethylhexyl) phthalate and di-n-butyl phthalate are most abundant species. PAEs concentrations for the four types of soils exhibited decreasing order as vegetable soil > wasteland soil > farmland soil > orchard soil. PAEs exhibited elevated levels in more developed regions when compared with other studies. The agricultural plastic film could elevate the PAEs contents in soils. Principal component analysis indicated the emission from cosmetics and personal care products and plasticizers were important sources for PAEs in suburban soils in Tianjin. The higher PAEs contents in wasteland soils from suburban area should be paid more attention owing to large amounts of solid wastes appeared with the ongoing urbanization. - Highlights: ► PAEs levels in four types of soils in suburban area of Tianjin were studied. ► Vegetable soil and wasteland soil exhibited higher PAEs concentrations. ► PAEs in wasteland soils from suburban area of cities in China should be paid attention. - (1) Vegetable soil and wasteland soil exhibited higher PAEs concentrations; (2) PAEs in wasteland soils from suburban area of cities in China should be paid attention.

  5. Bio-detoxification of phorbol esters and other anti-nutrients of Jatropha curcas seed cake by fungal cultures using solid-state fermentation.

    Science.gov (United States)

    Sharath, B S; Mohankumar, B V; Somashekar, D

    2014-03-01

    Jatropha seed cake, a byproduct after biodiesel extraction, has several anti-nutrients and toxins. Solid-state fermentation was carried out for the detoxification of the Jatropha seed cake (JSC) using different fungal cultures. The reduction in the anti-nutritional components such as tannins, phytates, saponins, lectin and protease inhibitor, and phorbol esters on 6th, 9th, and 12th day of fermentation was analyzed. The phorbol ester content in the unfermented JSC was 0.83 mg/g, and the maximum degradation of phorbol esters to the extent of 75% was observed in the case of JSC fermented with Cunninghamella echinulata CJS-90. The phytate degradation in the fermented JSC was in the range of 65-96%. There was a gradual reduction of saponin content in the JSC from 6th to 12th day, and the reduction of saponin was in the range of 55-99% after solid-state fermentation. The trypsin inhibitor activity and lectin were 1,680 trypsin inhibitor units (TIU) per gram and 0.32 hemagglutinating unit in the unfermented JSC, respectively. Trypsin inhibitor activity and lectin could not be detected in JSC after 12th day of solid-state fermentation. Tannins accounted for 0.53% in unfermented JSC, and there was a marginal increase of tannins after solid-state fermentation. The results indicate that biological detoxification could be a promising method to reduce anti-nutritional compounds and toxins in the JSC.

  6. List of Content

    Directory of Open Access Journals (Sweden)

    Editor IJRED

    2014-05-01

    Full Text Available CONTENTS OF ARTICLES page Tin (II Chloride Catalyzed Esterification of High FFA Jatropha Oil: Experimental and Kinetics Study DOI: 10.14710/ijred.3.2.75-81 75-81 Ratna Dewi Kusumaningtyas, Prima Astuti Handayani, Rochmadi Rochmadi, Suryo Purwono, Arief Budiman   Utilization of Iles-Iles and Sorghum Starch for Bioethanol Production DOI: 10.14710/ijred.3.2.83-89 83-89 Kusmiyati Kusmiyati, Agus Sulistiyono   Premixed Combustion of Kapok (ceiba pentandra seed oil on Perforated Burner DOI: 10.14710/ijred.3.2.91-97 91-97 I.K.G. Wirawan, I.N.G. Wardana,        Rudy Soenoko, Slamet Wahyudi   Castor Seed from Melkasa Agricultural Research Centre, East Showa, Ethiopia and it’s biodiesel performance in Four Stroke Diesel Engine DOI: 10.14710/ijred.3. 3.2.99-105 99-105 Tesfahun Tegegne Akanawa, Haimanot Gebrehiwot Moges, Ramesh Babu, Daniel Bisrat   Economic feasibility of large scale PV water pumping applications utilizing real field data for a case study in Jordan DOI: 10.14710/ijred.3.2.107-117 107-117 Ibrahim Odeh   Development of Briquette from Coir Dust and Rice Husk Blend: An Alternative Energy Source DOI: 10.14710/ijred.3.2.119-123 119-123 Md. Hamidul Islam, Md. Mosharraf Hossain,Md. Abdul Momin   Performance, Emissions and Combustion Characteristics of a Single Cylinder Diesel Engine Fuelled with Blends of Jatropha Methyl Ester and Diesel DOI: 10.14710/ijred.3.2.125-131 125-131 Debasish Padhee, Hifjur Raheman   The characteristic changes of betung bamboo (Dendrocalamus asper pretreated by fungal pretreatment DOI: 10.14710/ijred.3.2.133-143 133-143 Widya Fatriasari, Wasrin Syafii, Nyoman J Wistara, Khaswar Syamsu, Bambang Prasetya   Influence of the Determination Methods of K and C Parameters on the Ability of Weibull Distribution to Suitably Estimate Wind Potential and Electric Energy DOI: 10.14710/ijred.3.2.145-154 145-154 Ruben M. Mouangue, Myrin Y. Kazet, Alexis Kuitche, Jean-Marie Ndjaka    

  7. Repellent activity of monoterpenoid esters with neurotransmitter amino acids against yellow fever mosquito, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Nesterkina Mariia

    2018-03-01

    Full Text Available Repellent activity of monoterpenoid esters (1-6 with neurotransmitter amino acids (GABA and glycine was investigated against Aedes aegypti by using a “cloth-patch” assay and compared to reference standard N,N-diethyl-3-methylbenzamide (DEET. Monoterpenoid esters showed repellent activity with minimum effective dosages (MED in the range of 0.031-0.469 mg/cm2. The carvacrol ester of GABA (2, MED of 0.031 ± 0.008 mg/cm2 exhibited the highest repellency of six monoterpenoid esters tested in comparison to the standard repellent DEET (MED of 0.009 ± 0.002 mg/cm2; however, the repellent activity of carvacrol-glycine ester (5 decreased 4-fold compared to the carvacrol-GABA derivative (2. The repellent activities of menthol GABA (1, MED= 0.375 ± 0.000 mg/cm2 and glycine ester (4, MED=0.312 ± 0.063 mg/cm2 were similar The guaiacol-glycine ester (6 was 3.75-fold more efficacious than the guaiacol ester of GABA (3. In the present study, we report repellent efficacy of prolonged exposure to GABA and glycine esters of menthol, carvacrol, guaiacol (1-6 as compared to the repellent activities of their monoterpene moieties alone.

  8. Method for separating mono- and di-octylphenyl phosphoric acid esters

    International Nuclear Information System (INIS)

    Arnold, W.D. Jr.

    1977-01-01

    A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters

  9. Power distribution transformers using natural ester fluids as dielectric and coolant

    Directory of Open Access Journals (Sweden)

    Jorge Iván Silva-Ortega

    2016-12-01

    Full Text Available Researches related to the use of Natural Ester Fluids as a refrigerant of power transformers have been developed in other countries with successful results. In Colombia there is no a procedure to control the use of these esters in electrical apparatus, so the current implementations are regulated by NTC 1465 standards for mineral esters. This new proposal involves the composition and the most relevant properties (the ignition resistance, impact on the lifetime of the insulating papers and the impact on the environment, which makes the application of natural esters fluids advantageous not only to preserve the environment but also to get a better performance of power transformers.

  10. Triazole–Au(I complex as chemoselective catalyst in promoting propargyl ester rearrangements

    Directory of Open Access Journals (Sweden)

    Dawei Wang

    2011-07-01

    Full Text Available Triazole–Au (TA–Au catalysts were employed in several transformations involving propargyl ester rearrangement. Good chemoselectivity was observed, which allowed the effective activation of the alkyne without affecting the reactivity of the allene ester intermediates. These results led to the investigation of the preparation of allene ester intermediates with TA–Au catalysts under anhydrous conditions. As expected, the desired 3,3-rearrangement products were obtained in excellent yields (generally >90% yields with 1% loading. Besides the typical ester migrating groups, carbonates and carbamates were also found to be suitable for this transformation, which provided a highly efficient, practical method for the preparation of substituted allenes.

  11. Chromatographic, Spectrometric and NMR Characterization of a New Set of Glucuronic Acid Esters Synthesized by Lipase

    Directory of Open Access Journals (Sweden)

    Michel Marlier

    2007-01-01

    Full Text Available An enzymatic synthesis was developed on a new set of D-glucuronic acid esters and particularly the tetradecyl-D-glucopyranosiduronate also named tetradecyl D-glucuronate. Chromatographic analyses revealed the presence of the ester as a mixture of anomeric forms for carbon chain lengths superior to 12. TOF/MS and MS/MS studies confirmed the synthesis of glucuronic acid ester. The NMR study also confirmed the structure of glucuronic acid esters and clearly revealed an anomeric (α/β ratio equivalent to 3/2

  12. Engineering Potato Starch with a Higher Phosphate Content.

    Directory of Open Access Journals (Sweden)

    Xuan Xu

    Full Text Available Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-binding module and a dual-specificity phosphatase domain, is involved in the dephosphorylation of glycogen. To modify phosphate content and better understand starch (dephosphorylation in storage starch, laforin was engineered and introduced into potato (cultivar Kardal. Interestingly, expression of an (engineered laforin in potato resulted in significantly higher phosphate content of starch, and this result was confirmed in amylose-free potato genetic background (amf. Modified starches exhibited altered granule morphology and size compared to the control. About 20-30% of the transgenic lines of each series showed red-staining granules upon incubation with iodine, and contained higher phosphate content than the blue-stained starch granules. Moreover, low amylose content and altered gelatinization properties were observed in these red-stained starches. Principle component and correlation analysis disclosed a complex correlation between starch composition and starch physico-chemical properties. Ultimately, the expression level of endogenous genes involved in starch metabolism was analysed, revealing a compensatory response to the decrease of phosphate content in potato starch. This study provides a new perspective for engineering starch phosphate content in planta by making use of the compensatory mechanism in the plant itself.

  13. Melon oil methyl ester: an environmentally friendly fuel

    Directory of Open Access Journals (Sweden)

    S.K. Fasogbon

    2015-06-01

    Full Text Available Demand for energy is growing across the globe due to the direct relationship between the well-being and prosperity of people and energy usage. However, meeting this growing energy demand in a safe and environmentally friendly manner is a key challenge. To this end, methyl esters (biodiesels have been and are being widely investigated as alternatives to fossil fuels in compression ignition engines. In this study, melon (Colocynthis Citrullus Lanatus oil was used to synthesize biodiesel (methyl ester using the transesterification method in the presence of a sodium hydroxide promoter. The emissions profile of the biodiesel was investigated by setting up a single-cylinder four-stroke air-cooled CI engine connected to a TD115-hydraulic dynamometer and an Eclipse Flue Gas Analyzer (FGA with model number EGA4 flue gas analyzer. The engine was run at engine speeds of 675, 1200 and 1900rpm for biodiesel/diesel blends at 21°C on a volume basis of 0/100(B0, 10/90(B10, 20/80(B20, 30/70(B30, 40/60(B40 and 50/50(B50. The test showed a downward trend in the emissions profile of the biodiesel, with remarkable reductions of about 55% in the dangerous-carbon monoxide exhaust gas pollutant and 33.3% in the unfriendly SOX from 100% diesel to B30-biodiesel concentration. Increasing the speed from 675 to 1200 and then to 1900 rpm also afforded further reductions in CO and SOX exhaust emissions. NOX however increased marginally by 2.1% from the same 100% diesel to the B30-biodiesel composition. Based on the remarkable reduction in CO and SOX and the marginal increase in NOX as the concentration of the biodiesel increased in the blends, the study concludes that melon oil methyl ester is an environmentally friendly fuel.

  14. Preparation and characterization of a novel hyperbranched polyphosphate ester

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sufang [College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou, Jiangsu Province 215123 (China); Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan Institute of Technology, Wuhan, Hubei 430073 (China); Zhang, Daohong, E-mail: zhangdh@163.com [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China); Cheng, Xinjian; Li, Tingcheng; Zhang, Aiqing [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China); Li, Jinlin [College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou, Jiangsu Province 215123 (China); Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China)

    2012-11-15

    Polyphosphate esters have received a great deal of attention due to their important application in biomaterials field. Hyperbranched structure of polymers may support unique properties, including low viscosity and perfect intrinsic property. We report here three generations of hyperbranched polyphosphate esters (HPPE-1, HPPE-2 and HPPE-3) synthesized from a dehydrochlorination reaction between 1,3,5-tris(2-hydroxyethyl)cyanuric acid (THEIC) and phosphorus oxychloride (POCl{sub 3}), and characterize their chemical structures by FT-IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and 2D NMR ({sup 1}H,{sup 1}H-COSY and {sup 13}C, {sup 1}H-HSQC) techniques. Degrees of branching of HPPE-1, HPPE-2 and HPPE-3 are 0.90, 0.91 and 0.87 respectively from the calculation of their {sup 13}C NMR spectra. Molecular weights of HPPE-1, HPPE-2 and HPPE-3 are m/z 1530, 1768 and 2750 from their MALDI-TOF-MS spectra. Study on thermal degradation mechanism of the HPPE-2 by a 3D FT-IR/TG technology shows that there are two cracking processes of its molecular chains, including the thermal degradation of hydroxylethyl-ended groups, nitrogen heterocycle and -CH{sub 2}CH{sub 2}- groups of HPPE-2. -- Highlights: Black-Right-Pointing-Pointer We prepared three novel hyperbranched polyphosphate esters (HPPE-1, HPPE-2 and HPPE-3). Black-Right-Pointing-Pointer Their chemical structures were characterized by FT-IR, 1D NMR and 2D NMR techniques. Black-Right-Pointing-Pointer Their degrees of branching were over 0.87. Black-Right-Pointing-Pointer TG-FTIR was used to study thermal degradation mechanism of the HPPE-2.

  15. Carboxylesterase activities toward pesticide esters in crops and weeds.

    Science.gov (United States)

    Gershater, Markus; Sharples, Kate; Edwards, Robert

    2006-12-01

    Proteins were extracted from maize, rice, sorghum, soybean, flax and lucerne; the weeds Abutilon theophrasti, Echinochloa crus-galli, Phalaris canariensis, Setaria faberii, Setaria viridis, Sorghum halepense and the model plant Arabidopsis thaliana and assayed for carboxylesterase activity toward a range of xenobiotics. These included the pro-herbicidal esters clodinafop-propargyl, fenoxaprop-ethyl, fenthioprop-ethyl, methyl-2,4-dichlorophenoxyacetic acid (2,4-d-methyl), bromoxynil-octanoate, the herbicide-safener cloquintocet-mexyl and the pyrethroid insecticide permethrin. Highest activities were recorded with alpha-naphthyl acetate and methylumbelliferyl acetate. Esters of p-nitrophenol were also readily hydrolysed, with turnover declining as the chain length of the acyl component increased. Activities determined with model substrates were much higher than those observed with pesticide esters and were of limited value in predicting the relative rates of hydrolysis of the crop protection agents. Substrate preferences with the herbicides were typically 2,4-d-methyl>clodinafop-propargyl>fenthioprop-ethyl, fenoxaprop-ethyl and bromoxynil-octanoate. Isoelectric focussing in conjunction with staining for esterase activity using alpha-naphthyl acetate as substrate confirmed the presence of multiple carboxylesterase isoenzymes in each plant, with major qualitative differences observed between species. The presence of serine hydrolases among the resolved isoenzymes was confirmed through their selective inhibition by the organophosphate insecticide paraoxon. Our studies identify potentially exploitable differences between crops and weeds in their ability to bioactivate herbicides by enzymic hydrolysis and also highlight the usefulness of Arabidopsis as a plant model to study xenobiotic biotransformation.

  16. Dough and hearth bread characteristics influenced by protein composition, protein content, DATEM, and their interactions

    NARCIS (Netherlands)

    Aamodt, A.; Magnus, E.M.; Hollung, K.; Uhlen, A.K.; Færgestad, E.M.

    2005-01-01

    The effects of protein composition, protein content, diacetyl tartaric acid ester of monoglycerides (DATEM), and their interaction on dough and bread characteristics were studied by small- and pilot-scale hearth bread baking, dough rheological testing using the Kieffer extensibility rig, and size

  17. Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells.

    Science.gov (United States)

    Gause, K C; Homma, M K; Licciardi, K A; Seger, R; Ahn, N G; Peterson, M J; Krebs, E G; Meier, K E

    1993-08-05

    Phorbol ester-sensitive and -resistant EL4 thymoma cell lines differ in their ability to activate mitogen-activated protein kinase (MAPK) in response to phorbol ester. Treatment of wild-type EL4 cells with phorbol ester results in the rapid activations of MAPK and pp90rsk kinase, a substrate for MAPK, while neither kinase is activated in response to phorbol ester in variant EL4 cells. This study examines the activation of MAPK kinase (MAPKK), an activator of MAPK, in wild-type and variant EL4 cells. Phosphorylation of a 40-kDa substrate, identified as MAPK, was observed following in vitro phosphorylation reactions using cytosolic extracts or Mono Q column fractions prepared from phorbol ester-treated wild-type EL4 cells. MAPKK activity coeluted with a portion of the inactive MAPK upon Mono Q anion-exchange chromatography, permitting detection of the MAPKK activity in fractions containing both kinases. This MAPKK activity was present in phorbol ester-treated wild-type cells, but not in phorbol ester-treated variant cells or in untreated wild-type or variant cells. The MAPKK from wild-type cells was able to activate MAPK prepared from either wild-type or variant cells. MAPKK activity could be stimulated in both wildtype and variant EL4 cells in response to treatment of cells with okadaic acid. These results indicate that the failure of variant EL4 cells to activate MAP kinase in response to phorbol ester is due to a failure to activate MAPKK. Therefore, the step that confers phorbol ester resistance to variant EL4 cells lies between the activation of protein kinase C and the activation of MAPKK.

  18. Acridinium esters as high-specific-activity labels in immunoassay

    International Nuclear Information System (INIS)

    Weeks, I.; Beheshti, I.; McCapra, F.; Campbell, A.K.; Woodhead, J.S.

    1983-01-01

    A chemiluminescent acridinium ester has been synthesized that reacts spontaneously with proteins to yield stable, immunoreactive derivatives of high specific activity. The compound has been used to prepare chemiluminescent monoclonal antibodies to human alpha 1-fetoprotein having average incorporation ratios as great as 2.8 mol of label per mole of antibody, which corresponds to a detection limit of approximately 8 X 10(-19) mol. These antibodies have been used in the preliminary development of a two-site immunochemiluminometric assay for human alpha 1-fetoprotein, which requires only a 30-min incubation and a quantification time of 5 s per sample

  19. Boronate esters: Synthesis, characterization and molecular base receptor analysis

    Science.gov (United States)

    Gómez-Jaimes, Gelen; Barba, Victor

    2014-10-01

    The synthesis of three boronate esters obtained by reacting 4-fluorophenylboronic (1), 4-iodophenylboronic (2) and 3,4-chlorophenylboronic (3) acids with 2,4,5-trihidroxybenzaldehyde is reported. The structural characterization was determined by spectroscopic and spectrometric techniques. The boron atom was evaluated to acts as Lewis acid center in the reaction with pyridine (Py), triethylamine (TEA) and fluoride anion (F-). The titration method was followed by UV-Vis and 11B NMR spectroscopy; results indicate the good interaction with the fluoride ion but poor coordination towards pyridine in solution.

  20. Green Synthesis of Acid Esters from Furfural via Stobbe Condensation

    Directory of Open Access Journals (Sweden)

    Shubhra Banerjee

    2013-01-01

    Full Text Available Solvent-free Stobbe condensation of furfural 1 with dimethyl succinate 2 under anhydrous conditions at room temperature using dry-solid potassium tertiary butoxide gave 3-carbomethoxy, 4-furyl-3-butenoic acid 3, which upon methylation followed by Stobbe condensation reaction with different aldehydes and/or ketones under anhydrous conditions at room temperature afforded substituted carbomethoxy acids 5a–f. These acid ester products were saponified to the corresponding dicarboxylic acids 6a–f which are useful in the synthesis of photochromic fulgides.

  1. Spectral Analyses of a Novel Ibuprofen-Phillygenin Ester

    Directory of Open Access Journals (Sweden)

    FAN Hong-yu

    2018-03-01

    Full Text Available An ibuprofen-phillygenin ester was synthesized through the Schotten-Baumann reaction with ibuprofen and phillygenin as the starting materials. Ultraviolet absorption (UV spectrum, infrared absorption (IR spectrum, matrix-assisted laser desorption/ionization-mass spectra (MALDI-TOF-MS, and one-dimensional/two dimensional nuclear magnetic resonance (NMR spectra (i.e., 1H-NMR, 13C-NMR, 13C-DEPT, 1H-1H COSY, 1H-1H NOESY, 1H-13C HSQC and 1H-13C HMBC of the compound were collected. All 1H and 13C NMR signals were assigned.

  2. Release of superoxide and change in morphology by neutrophils in response to phorbol esters: antagonism by inhibitors of calcium-binding proteins

    Science.gov (United States)

    1985-01-01

    The ability of phorbol derivatives to function as stimulating agents for superoxide (O2-) release by guinea pig neutrophils has been evaluated and compared to the known ability of each compound to activate protein kinase C. Those that activate the kinase also stimulate O2- release, while those that are inactive with respect to the kinase have no effect on O2- release. The same correlation was observed with respect to the ability of phorbol esters to induce morphological changes in neutrophils, i.e., vesiculation and reduction in granule content. Certain phenothiazines and naphthalene sulfonamides that are known antagonists of calcium-binding proteins blocked both phorbol ester-induced O2- release and morphological changes in these cells. PMID:2993312

  3. One step hydrogenation–esterification of model compounds and bio-oil to alcohols and esters over Raney Ni catalysts

    International Nuclear Information System (INIS)

    Xu, Ying; Zhang, Limin; Chang, Jiamin; Zhang, Xinghua; Ma, Longlong; Wang, Tiejun; Zhang, Qi

    2016-01-01

    Highlights: • Fe–RN and Mo–RN showed excellent inhibition of alkylation and hydrogenation activity of phenol respectively. • The esterification activity of alcohols with acetic acid was followed as methanol > THFA > ethanediol. • After OHE of bio-oil, the total content of alcohols and esters reached to 87.27% in the product. - Abstract: Acids, aldehydes, ketones and phenols, which are the main components of bio-oil, have negative effects on the properties. In this paper, the mixture of acetic acid, furfural, hydroxyacetone, ethanediol, phenol and water were chosen as hybrid model compounds of bio-oil (MCB). To convert these compounds into stable and combustible oxygenated organics (alcohols and esters), one step hydrogenation–esterification (OHE) was carried out over Raney Ni catalyst (RN) and Mo, Sn, Fe, Cu modified Raney Ni catalysts (RNs) in the presence of methanol. 100% conversions of furfural and hydroxyacetone were achieved over RNs with high selectivity to desired products. The acetic acid conversion was only 35.1% with no methanol addition, while within 6 g/8 g methanol/MCB addition, the conversion of acetic acid increased to 81.1%. The esterification activity of alcohols was followed by methanol > tetrahydrofurfuryl alcohol (THFA), the hydrogenation product of furfural > ethanediol. Among the RNs, the addition of Fe catalyst restrained the aqueous-phase reforming of methanol and promoted the esterification of methanol and acetic acid. The Mo–RN showed the most favorable performance in the hydrogenation of phenol among the RNs. But the RN modified by both Fe and Mo did not give a good performance. After the OHE of light fraction of raw bio-oil over Mo–RN, there was no ketone & aldehyde detected and the contents of acids and phenols decreased from 49.04% and 7.35% to 8.21% and 3.84%. The conversion of acids could reach to 85.01% which was nearly to the conversion of acetic acid in MCB. The contents of alcohols and esters increased from 5

  4. Hidrofilicidade de filmes de amido/poli(butileno adipato co-tereftalato (Pbat adicionados de tween 80 e óleo de soja Hydrophilicity of starch and poly(butylene adipate-co-terephthalate (Pbat films containing tween 80 and soybean oil

    Directory of Open Access Journals (Sweden)

    Renata P. Herrera Brandelero

    2013-01-01

    Full Text Available A incorporação de amido ao polímero poli (butilenoadipatoco-tereftalato (PBAT através de blendas com alto teor de amido pode ser uma alternativa para obter embalagens biodegradáveis, minimizar custos e o uso de recursos não renováveis. No entanto, a adição de amido aumenta a permeabilidade ao vapor de água (PVA. A incorporação em filmes com amido de substâncias como óleos vegetais e surfactantes pode diminuir a hidrofilicidade, favorecendo as aplicações destes como embalagens. A hidrofilicidade dos filmes elaborados por blendas de amido/PBAT adicionados de óleo de soja (OS e tween 80 (TW foi avaliada considerando o efeito do OS e TW nas isotermas de sorção dos filmes, na PVA e nos coeficientes de difusão (Dw e solubilidade (β do vapor de água. Filmes com OS com ou sem TW apresentaram menor quantidade de água de sorção, sendo os filmes com menores quantidades de OS e sem TW menos hidrofílicos e menos permeáveis aos vapores de água. A adição de OS reduziu os valores de β e Dw dos filmes de amido/PBAT. O efeito foi relacionado com o aumento das porções hidrofóbicas e da compatibilidade entre o amido e PBAT na presença de OS.Incorporating starch into the poly(butylene adipate-co-terephthalate (PBAT polymer by means of blends with high starch contents is a possible option for producing biodegradable packaging using renewable resources and reducing costs. However, the addition of starch increases the water vapour permeability (WVP. The incorporation of substances as lipids and surfactants can reduce the hydrophilicity of films containing starch, favouring their use as packaging. The hydrophilicity of films produced from blends of starch/PBAT with added soybean oil (SO and tween 80 (TW was studied. The effects of these substances on the sorption isotherm, on the WVP and on the water vapour diffusion (Dw and solubility (β coefficients of the films were evaluated. The water sorption in films with SO, with or without TW

  5. Effects of fatty acid methyl esters proportion on combustion and emission characteristics of a biodiesel fueled diesel engine

    International Nuclear Information System (INIS)

    E, Jiaqiang; Liu, Teng; Yang, W.M.; Li, Jing; Gong, Jinke; Deng, Yuanwang

    2016-01-01

    Highlights: • The effects of FAMEs proportion on combustion and emission were numerically studied. • The impact of the saturation level on combustion characteristic is not straightforward. • The NO_x emission is mainly related to the fuel kinetic viscosity. - Abstract: With the growing energy problems, scholars has focused on utilizing renewable biodiesel as a fossil fuel alternative. Four different typical biodiesels were employed to investigate the effects of fatty acid methyl esters proportion on combustion and emission characteristics of a biodiesel fueled diesel engine in terms of heat release rate, cylinder pressure, indicated power and formation of NO_x emission. The corresponding computational fluid dynamic modeling was performed by KIVA4 coupled CHEMKIN II code, and a special chemical kinetics mechanism consisting of 106 species and 263 reactions was developed to simulate the combustion process since it contained methyl linoleate, a majority component in most biodiesel, thereby improved the accuracy of simulation. The simulation results indicated that chemical ignition delay time and kinetic viscosity of biodiesel played very important roles in combustion process. Higher saturation level could shorten chemical ignition delay time, but the higher saturation contents like C16:0 and C18:0 together with C18:1 (a single double bond methyl ester) would increase the kinetic viscosity, resulting in poor fuel–air mixing and evaporation process. Lower kinetic viscosity methyl esters like C18:2 and C18:3 was favorable for better fuel–air mixing and subsequent combustion, however, a higher NO_x emission was discovered. Therefore, the relationship between saturation levels and combustion and emission characteristics of biodiesels is not simple and straightforward, the balance of five majority components is very important.

  6. The Phorbol Ester Fraction from Jatropha curcas Seed Oil: Potential and Limits for Crop Protection against Insect Pests

    Science.gov (United States)

    Ratnadass, Alain; Wink, Michael

    2012-01-01

    The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a “miracle tree”, particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the “boom” in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed. PMID:23203190

  7. The phorbol ester fraction from Jatropha curcas seed oil: potential and limits for crop protection against insect pests.

    Science.gov (United States)

    Ratnadass, Alain; Wink, Michael

    2012-11-30

    The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a "miracle tree", particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the "boom" in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed.

  8. Conformational states of N-acylalanine dithio esters: correlation of resonance Raman spectra with structures

    International Nuclear Information System (INIS)

    Lee, H.; Angus, R.H.; Storer, A.C.; Varughese, K.I.; Carey, P.R.

    1988-01-01

    The conformational states of N-acylalanine dithio esters, involving rotational isomers about the RC(=O)NH-CH(CH 3 ) and NHCH(CH 3 )-C(=S) bonds, are defined and compared to those of N-acylglycine dithio esters. The structure of N-(p-nitrobenzoyl)-DL-alanine ethyl dithio ester has been determined by X-ray crystallographic analysis; it is a B-type conformer with the amide N atom cis to the thiol sulfur. Raman and resonance Raman (RR) measurements on this compound and for the B conformers of solid N-benzoyl-DL-alanine ethyl dithio ester and N-(β-phenylpropionyl)-DL-alanine ethyl dithio ester and its NHCH(CD 3 )C(=S) and NHCH(CH 3 ) 13 C(=S) analogues are used to set up a library of RR data for alanine-based dithio esters in a B-conformer state. RR data for this solid material in its isotopically unsubstituted and CH(C-D 3 )C(=S) and CH(CH 3 ) 13 C(=S) forms provide information on the RR signatures of alanine dithio esters in A-like conformations. RR spectra are compared for the solid compounds, for N-(p-nitrobenzoyl)-DL-alanine, N-(β-phenylpropionyl)-DL-alanine, and (methyloxycarbonyl)-L-phenylalanyl-DL-alanine ethyl dithio ester, and for several 13 C=S- and CD 3 -substituted analogues in CCl 4 or aqueous solutions. The RR data demonstrate that the alanine-based dithio esters take up A, B, and C 5 conformations in solution. The RR spectra of these conformers are clearly distinguishable from those for the same conformers of N-acylglycine dithio esters. However, the crystallographic and spectroscopic results show that the results show that the conformational properties of N-acylglycine and N-acylalanine dithio esters are very similar

  9. Thermal Properties of Methyl Ester-Containing Poly(2-oxazolines

    Directory of Open Access Journals (Sweden)

    Petra J. M. Bouten

    2015-10-01

    Full Text Available This paper describes the synthesis and thermal properties in solution and bulk of poly(2-alkyl-oxazolines (PAOx containing a methyl ester side chain. Homopolymers of 2-methoxycarbonylethyl-2-oxazoline (MestOx and 2-methoxycarbonylpropyl-2-oxazoline (C3MestOx, as well as copolymers with 2-ethyl-2-oxazoline (EtOx and 2-n-propyl-2-oxazoline (nPropOx, with systematic variations in composition were prepared. The investigation of the solution properties of these polymers revealed that the cloud point temperatures (TCPs could be tuned in between 24 °C and 108 °C by variation of the PAOx composition. To the best of our knowledge, the TCPs of PMestOx and PC3MestOx are reported for the first time and they closely resemble the TCPs of PEtOx and PnPropOx, respectively, indicating similar hydrophilicity of the methyl ester and alkyl side chains. Furthermore, the thermal transitions and thermal stability of these polymers were investigated by DSC and TGA measurements, respectively, revealing amorphous polymers with glass transition temperatures between -1 °C and 54 °C that are thermally stable up to >300 °C.

  10. Growth of glycine ethyl ester hydrochloride and its characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, G.; Pari, S., E-mail: sparimyur@gmail.com

    2016-11-15

    Single crystal of glycine ethyl ester hydrochloride by slow evaporation method is reported. The grown crystal characterized by single crystal X-ray diffraction, FT-IR, UV–Vis–NIR and fluorescence spectroscopy. It is established that the crystal falls under the monoclinic system and space group P21/c with the cell parameters as: a=8.565 Å, b=12.943 Å, c=6.272 Å, α=γ=90°, β=103.630º. UV–Vis–NIR spectrum shows indirect allowed transition with a band gap of 5.21 eV and other optical properties are measured. The crystal is also shown to have a high transmittance in the visible region. The third order nonlinear property and optical limiting have been investigated using Z-Scan technique. Complex impedance spectrum measured at the dc conductivity. Dependence of dielectric constant, dielectric loss and ac conductivity on frequency at different temperature of applied ac field is analyzed. The mechanical behavior has been assessed by Vickers microhardness indenter. The thermal behavior of glycine ethyl ester hydrochloride was analyzed using TG/DTA thermal curves. From the thermal study, the material was found to possess thermal stability up to 174 °C. The predicted NLO properties, UV–Vis transmittance and Z-scan studies indicate that is an attractive material for photonics optical limiting applications.

  11. Microreactors—A Powerful Tool to Synthesize Peroxycarboxylic Esters

    Directory of Open Access Journals (Sweden)

    Tobias Illg

    2015-12-01

    Full Text Available The synthesis of peroxycarboxylic esters, as one subgroup of organic peroxides, is characterized by a high thermal hazard potential regarding process safety. In case of failure in the production process, e.g., if the heat of reaction cannot be removed sufficiently fast, decomposition reactions can be triggered, and as a result, remarkable amounts of heat and gas can be released and can cause a high extent of damage. Multifarious technical and organizational measures are necessary to ensure the safe industrial production of peroxides. With the introduction of microreaction technology plenty of possibilities have been opened to carry out highly exothermic reactions in smaller volumes and with more efficient heat removal. In this paper we report the application of three different microstructured reactors, representing different mixing strategies, to synthesize two peroxymonocarboxylic esters, namely tert-butyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate. The following reactor types were considered: an orifice microreactor, a split and recombine microreactor and a capillary tube reactor in combination with ultrasonication. The efficiency of the two phase liquid/liquid reaction is expressed in comparison of conversion and selectivity. With microreaction technology a remarkable increase in space-time-yield, ranging from 12,500 kg·m−3·h−1 to 414,000 kg·m−3·h−1, is achieved.

  12. Novel fatty acid methyl esters from the actinomycete Micromonospora aurantiaca

    Science.gov (United States)

    Bruns, Hilke; Riclea, Ramona

    2011-01-01

    Summary The volatiles released by Micromonospora aurantiaca were collected by means of a closed-loop stripping apparatus (CLSA) and analysed by GC–MS. The headspace extracts contained more than 90 compounds from different classes. Fatty acid methyl esters (FAMEs) comprised the major compound class including saturated unbranched, monomethyl and dimethyl branched FAMEs in diverse structural variants: Unbranched, α-branched, γ-branched, (ω−1)-branched, (ω−2)-branched, α- and (ω−1)-branched, γ- and (ω−1)-branched, γ- and (ω−2)-branched, and γ- and (ω−3)-branched FAMEs. FAMEs of the last three types have not been described from natural sources before. The structures for all FAMEs have been suggested based on their mass spectra and on a retention index increment system and verified by the synthesis of key reference compounds. In addition, the structures of two FAMEs, methyl 4,8-dimethyldodecanoate and the ethyl-branched compound methyl 8-ethyl-4-methyldodecanoate were deduced from their mass spectra. Feeding experiments with isotopically labelled [2H10]leucine, [2H10]isoleucine, [2H8]valine, [2H5]sodium propionate, and [methyl-2H3]methionine demonstrated that the responsible fatty acid synthase (FAS) can use different branched and unbranched starter units and is able to incorporate methylmalonyl-CoA elongation units for internal methyl branches in various chain positions, while the methyl ester function is derived from S-adenosyl methionine (SAM). PMID:22238549

  13. Poly(ortho esters)--from concept to reality.

    Science.gov (United States)

    Heller, Jorge; Barr, John

    2004-01-01

    The development of poly(ortho esters) dates back to the early 1970s, and during that time, four distinct families were developed. These polymers can be prepared by a transesterification reaction or by the addition of polyols to diketene acetals, and it is the latter method that has proven to be preferred one. The latest polymer, now under intense development, incorporates a latent acid segment in the polymer backbone that takes advantage of the acid-labile nature of the ortho ester linkages and allows control over erosion rates. By use of diols having selected chain flexibility, polymers that range from hard, brittle materials to materials that have a gel-like consistency at room temperature can be obtained. Drug release from solid materials will be illustrated with 5-fluorouacil and bovine serum albumin, and drug release from gel-like materials will be illustrated with mepivacaine, now in Phase II clinical trials as a delivery system to treat post-operative pain. A brief summary of preclinical toxicology studies is also presented.

  14. N-hydroxysuccinimide-hippuran ester: application for radiolabeling of macromolecules

    International Nuclear Information System (INIS)

    Chervu, L.R.; Chun, S.B.; Bhargava, K.K.

    1987-01-01

    A method for synthesis of N-hydroxysuccinimide ester of radioactive orthoiodohippurric acid (OIH-OSU) is developed in order to label macromolecules including antibodies. The OIH-OSU is prepared in 87% yield by reacting molar equivalents of o-iodohippuric acid, N:N-di-succinimidyl carbonate and pyridine in DMF overnight. The active labeled ester is obtained using high specific activity OIH in a similar synthetic protocol. Conjugation of OIH-OSU to human serum albumin is effected by incubating the reactants for half an hour at room temperature followed by purification of the labeled protein on a Sephadex G-100 column with activity yield of 44.3%. Organ distribution for the labeled albumin preparation and the commercial iodinated human serum albumin (RISA) in mice and rats is similar. As expected urinary excretion of radioactivity for the labeled preparation is greater than that of RISA reflecting the rapid urinary clearance of the OIH moiety released into the bloodstream. Hippuran labeling method offers a mild and rapid protocol for radioiodine labeling of proteins and antibodies for application in diagnostic nuclear medicine procedures

  15. Hepatic cholesterol ester hydrolase in human liver disease.

    Science.gov (United States)

    Simon, J B; Poon, R W

    1978-09-01

    Human liver contains an acid cholesterol ester hydrolase (CEH) of presumed lysosomal origin, but its significance is unknown. We developed a modified CEH radioassay suitable for needle biopsy specimens and measured hepatic activity of this enzyme in 69 patients undergoing percutaneous liver biopsy. Histologically normal livers hydrolyzed 5.80 +/- 0.78 SEM mumoles of cholesterol ester per hr per g of liver protein (n, 10). Values were similar in alcoholic liver disease (n, 17), obstructive jaundice (n, 9), and miscellaneous hepatic disorders (n, 21). In contrast, mean hepatic CEH activity was more than 3-fold elevated in 12 patients with acute hepatitis, 21.05 +/- 2.45 SEM mumoles per hr per g of protein (P less than 0.01). In 2 patients studied serially, CEH returned to normal as hepatitis resolved. CEH activity in all patients paralleled SGOT levels (r, 0.84; P less than 0.01). There was no correlation with serum levels of free or esterified cholesterol nor with serum activity of lecithin-cholesterol acyltransferase, the enzyme responsible for cholesterol esterification in plasma. These studies confirm the presence of CEH activity in human liver and show markedly increased activity in acute hepatitis. The pathogenesis and clinical significance of altered hepatic CEH activity in liver disease require further study.

  16. Determination of 3-Monochloropropane-1,2-diol and 2-Monochloropropane-1,3-diol (MCPD) Esters and Glycidyl Esters by Microwave Extraction in Different Foodstuffs.

    Science.gov (United States)

    Marc, Corinne; Drouard-Pascarel, Valérie; Rétho, Cécile; Janvion, Patrice; Saltron, Frédéric

    2016-06-01

    This paper describes a method for the determination of 3-monochloropropane-1,2-diol and 2-monochloropropane-1,3-diol (MCPD) esters and glycidyl esters in various foodstuffs, which are isolated using microwave extraction. The next step is based on alkaline-catalyzed ester cleavage. The released glycidol is transformed into monobromopropanediol (MBPD). All compounds are derivatized in free diols (MCPD and MBPD) with phenylboronic acid and analyzed by gas chromatography-mass spectrometry (GC-MS). The method was validated for oils with a limit of quantitation (LOQ) of 0.1 mg/kg, for chips and crisps with a LOQ of 0.02 mg/kg, and for infant formula with a LOQ of 0.0025 mg/L. Recoveries of each sample were controlled by standard addition on extracts before derivatization. Quantitation was performed by the addition of isotopically labeled glycidyl and 3-monochloropropane-1,2-diol (3-MCPD) esters.

  17. Transformation of Unsaturated Fatty Acids/Esters to Corresponding Keto Fatty Acids/Esters by Aerobic Oxidation with Pd(II)/Lewis Acid Catalyst.

    Science.gov (United States)

    Senan, Ahmed M; Zhang, Sicheng; Zeng, Miao; Chen, Zhuqi; Yin, Guochuan

    2017-08-16

    Utilization of renewable biomass to partly replace the fossil resources in industrial applications has attracted attention due to the limited fossil feedstock with the increased environmental concerns. This work introduced a modified Wacker-type oxidation for transformation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, in which Cu 2+ cation was replaced with common nonredox metal ions, that is, a novel Pd(II)/Lewis acid (LA) catalyst. It was found that adding nonredox metal ions can effectively promote Pd(II)-catalyzed oxidation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, even much better than Cu 2+ , and the promotional effect is highly dependent on the Lewis acidity of added nonredox metal ions. The improved catalytic efficiency is attributed to the formation of heterobimetallic Pd(II)/LA species, and the oxidation mechanism of this Pd(II)/LA catalyst is also briefly discussed.

  18. Used frying oils and fats and their utilization in the production of methyl esters of higher fatty acids

    Energy Technology Data Exchange (ETDEWEB)

    Cvengros, J. Jan; Cvengrosova, Zuzana [Slovak Univ. of Technology, Faculty of Chemical and Food Technology, Bratislava (Slovakia)

    2004-08-01

    From the point of view price and available capacity used frying oils or fats (UFO) represent an attractive raw material for the production of methyl esters (ME) of higher fatty acids as alternative fuels for diesel engines. If they are treated such that the required quality, with an acidity number up to 3.0 mg KOH/g and a water content up to 0.1 wt%, is achieved they can be processed to ME using standard techniques of alkali-catalysed transesterification with methanol which are utilized for production of the ME from new oils/fats. The problematic waste can thus be converted to an ecologically friendly fuel. Vacuum distillation of free fatty acids in a film evaporator is an effective method for simultaneously decreasing the content of FFA and water in UFO. Final distillation of raw ME in a film vacuum evaporator results in practically all parameters required by the standard, in the final ME being achieved. Undesirable low-temperature properties of ME derived from UFO, due to higher fraction of saturated acyls, can be adjusted by the addition of depressants-flow improvers for winterization. Some simplified methods for the quality control of UFO and ME are discussed. The conversion of acylglycerols to ME is monitored by GLC with a packed column, where the peak areas of ME in the sample before and after the reaction with an effective methylation agent are compared. The method for the determination of the water content in esters utilizes the reaction of calcium carbide with water, the volume of acetylene being measured. (Author)

  19. Potential Grape-Derived Contributions to Volatile Ester Concentrations in Wine

    Directory of Open Access Journals (Sweden)

    Paul K. Boss

    2015-04-01

    Full Text Available Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl ester production above that of the control was apparent when lower concentrations of the C9 compounds were added to the model musts compared to the C12 compounds. Four amino acids, which are involved in CoA biosynthesis, were also added to model grape juice medium in the absence of pantothenate to test their ability to influence ethyl and acetate ester production. β-Alanine was the only one shown to increase the production of ethyl esters, free fatty acids and acetate esters. The addition of 1 mg∙L−1 β-alanine was enough to stimulate production of these compounds and addition of up to 100 mg∙L−1 β-alanine had no greater effect. The endogenous concentrations of β-alanine in fifty Cabernet Sauvignon grape samples exceeded the 1 mg∙L−1 required for the stimulatory effect on ethyl and acetate ester production observed in this study.

  20. Potential grape-derived contributions to volatile ester concentrations in wine.

    Science.gov (United States)

    Boss, Paul K; Pearce, Anthony D; Zhao, Yanjia; Nicholson, Emily L; Dennis, Eric G; Jeffery, David W

    2015-04-29

    Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl ester production above that of the control was apparent when lower concentrations of the C9 compounds were added to the model musts compared to the C12 compounds. Four amino acids, which are involved in CoA biosynthesis, were also added to model grape juice medium in the absence of pantothenate to test their ability to influence ethyl and acetate ester production. β-Alanine was the only one shown to increase the production of ethyl esters, free fatty acids and acetate esters. The addition of 1 mg∙L(-1) β-alanine was enough to stimulate production of these compounds and addition of up to 100 mg∙L(-1) β-alanine had no greater effect. The endogenous concentrations of β-alanine in fifty Cabernet Sauvignon grape samples exceeded the 1 mg∙L(-1) required for the stimulatory effect on ethyl and acetate ester production observed in this study.

  1. Increased large VLDL particles confer elevated cholesteryl ester transfer in diabetes

    NARCIS (Netherlands)

    Dullaart, Robin P. F.; de Vries, Rindert; Kwakernaak, Arjan J.; Perton, Frank; Dallinga-Thie, Geesje M.

    BackgroundPlasma cholesteryl ester transfer (CET), reflecting transfer of cholesteryl esters from high density lipoproteins (HDL) towards apolipoprotein B-containing lipoproteins, may promote atherosclerosis development, and is elevated in Type 2 diabetes mellitus (T2DM). We determined the extent to

  2. Effect of Silicon Substitution on the Crystal Properties of Cyanate Ester Monomers (Briefing Charts)

    Science.gov (United States)

    2015-08-17

    unlimited.   Outline • Background / Motivation – Cyanate esters – Reasons for incorporating silicon into thermosetting resins • Cyanate esters with...Approved for public release; distribution is unlimited.   The Use of Si in Thermosetting Polymers • In addition to the expected increase in short

  3. 40 CFR 721.3680 - Ethylene oxide adduct of fatty acid ester with pentaerythritol.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Ethylene oxide adduct of fatty acid... New Uses for Specific Chemical Substances § 721.3680 Ethylene oxide adduct of fatty acid ester with... identified generically as ethylene oxide adduct of fatty acid ester with pentaerythritol (PMN P-91-442) is...

  4. Chemical modifications of Sterculia foetida L. oil to branched ester derivatives

    NARCIS (Netherlands)

    Manurung, Robert; Daniel, Louis; van de Bovenkamp, Hendrik H.; Buntara, Teddy; Maemunah, Siti; Kraai, Gerard; Makertihartha, I. G. B. N.; Broekhuis, Antonius A.; Heeres, Hero J.

    An experimental study to modify Sterculia foetida L. oil (STO) or the corresponding methyl esters (STO FAME) to branched ester derivatives is reported. The transformations involve conversion of the cyclopropene rings in the fatty acid chains of STO through various catalytic as well as stoichiometric

  5. A Lactobacillus plantarum Esterase Active on a Broad Range of Phenolic Esters

    Science.gov (United States)

    Esteban-Torres, María; Landete, José María; Reverón, Inés; Santamaría, Laura; de las Rivas, Blanca

    2015-01-01

    Lactobacillus plantarum is the lactic acid bacterial species most frequently found in the fermentation of food products of plant origin on which phenolic compounds are abundant. L. plantarum strains showed great flexibility in their ability to adapt to different environments and growth substrates. Of 28 L. plantarum strains analyzed, only cultures from 7 strains were able to hydrolyze hydroxycinnamic esters, such as methyl ferulate or methyl caffeate. As revealed by PCR, only these seven strains possessed the est_1092 gene. When the est_1092 gene was introduced into L. plantarum WCFS1 or L. lactis MG1363, their cultures acquired the ability to degrade hydroxycinnamic esters. These results support the suggestion that Est_1092 is the enzyme responsible for the degradation of hydroxycinnamic esters on the L. plantarum strains analyzed. The Est_1092 protein was recombinantly produced and biochemically characterized. Surprisingly, Est_1092 was able to hydrolyze not only hydroxycinnamic esters, since all the phenolic esters assayed were hydrolyzed. Quantitative PCR experiments revealed that the expression of est_1092 was induced in the presence of methyl ferulate, an hydroxycinnamic ester, but was inhibited on methyl gallate, an hydroxybenzoic ester. As Est_1092 is an enzyme active on a broad range of phenolic esters, simultaneously possessing feruloyl esterase and tannase activities, its presence on some L. plantarum strains provides them with additional advantages to survive and grow on plant environments. PMID:25746986

  6. PLE CATALYZED HYDROLYZES OF ALPHA-SUBSTITUTED ALPHA-HYDROXY ESTERS - THE INFLUENCE OF THE SUBSTITUENTS

    NARCIS (Netherlands)

    MOORLAG, H; KELLOGG, RM

    1991-01-01

    The enzymatic hydrolyses of a variety of alpha-substituted mandelic and lactic esters using pig liver esterase (PLE) have been investigated. High to moderate enantioselectivity was found for various alpha-substituted mandelic esters, whereas PLE showed low to no enantioselectivity for

  7. Stereoselective formation of a cholesterol ester conjugate from fenvalerate by mouse microsomal carboxyesterase(s).

    Science.gov (United States)

    Miyamoto, J; Kaneko, H; Takamatsu, Y

    1986-06-01

    In accordance with in vivo findings, of the four chiral isomers of fenvalerate (S-5602 Sumicidin, Pydrin, [RS]-alpha-cyano-3-phenoxybenzyl [RS]-2-(4-chlorophenyl)isovalerate), only the [2R, alpha S]-isomer (B-isomer) yielded cholesteryl [2R]-2-(4-chlorophenyl)isovalerate (CPIA-cholesterol ester) in the in vitro study using several tissue homogenates of mice, rats, dogs, and monkeys. There were species differences in the extent of CPIA-cholesterol-ester formation, with mouse tissues showing relatively higher activity than those of other animals. The kidney, brain, and spleen of mice showed relatively higher capacities to form this ester compared to other tissues, and the enzyme activity was mainly localized in microsomal fractions. The CPIA-cholesterol ester did not seem to be produced by three known biosynthetic pathways of endogenous cholesterol esters--acyl-CoA:cholesterol O-acyltransferase (ACAT), lecithin:cholesterol O-acyltransferase (LCAT), and cholesterol esterase. Carboxyesterase(s) of mouse kidney microsomes solubilized by digitonin hydrolyzed only the B alpha-isomer of fenvalerate, yielding CPIA, whereas they yielded the corresponding cholesterol ester in the presence of artificial liposomes containing cholesterol. Thus, it appears that the stereoselective formation of the CPIA-cholesterol ester results from the stereoselective formation of the CPIA-carboxyesterase complex only from the B alpha-isomer, which subsequently undergoes cleavage by cholesterol to yield the CPIA-cholesterol ester.

  8. A Lactobacillus plantarum esterase active on a broad range of phenolic esters.

    Science.gov (United States)

    Esteban-Torres, María; Landete, José María; Reverón, Inés; Santamaría, Laura; de las Rivas, Blanca; Muñoz, Rosario

    2015-05-01

    Lactobacillus plantarum is the lactic acid bacterial species most frequently found in the fermentation of food products of plant origin on which phenolic compounds are abundant. L. plantarum strains showed great flexibility in their ability to adapt to different environments and growth substrates. Of 28 L. plantarum strains analyzed, only cultures from 7 strains were able to hydrolyze hydroxycinnamic esters, such as methyl ferulate or methyl caffeate. As revealed by PCR, only these seven strains possessed the est_1092 gene. When the est_1092 gene was introduced into L. plantarum WCFS1 or L. lactis MG1363, their cultures acquired the ability to degrade hydroxycinnamic esters. These results support the suggestion that Est_1092 is the enzyme responsible for the degradation of hydroxycinnamic esters on the L. plantarum strains analyzed. The Est_1092 protein was recombinantly produced and biochemically characterized. Surprisingly, Est_1092 was able to hydrolyze not only hydroxycinnamic esters, since all the phenolic esters assayed were hydrolyzed. Quantitative PCR experiments revealed that the expression of est_1092 was induced in the presence of methyl ferulate, an hydroxycinnamic ester, but was inhibited on methyl gallate, an hydroxybenzoic ester. As Est_1092 is an enzyme active on a broad range of phenolic esters, simultaneously possessing feruloyl esterase and tannase activities, its presence on some L. plantarum strains provides them with additional advantages to survive and grow on plant environments. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Experimental and Modeling Studies on the Synthesis and Properties of Higher Fatty Esters of Corn Starch

    NARCIS (Netherlands)

    Junistia, Laura; Sugih, Asaf K.; Manurung, Robert; Picchioni, Francesco; Janssen, Leon P. B. M.; Heeres, Hero J.

    This paper describes a systematic study on the synthesis of higher fatty esters of corn starch (starch laurate and starch stearate) by using the corresponding vinyl esters. The reactions were carried out in DMSO using basic catalysts (Na(2)HPO(4), K(2)CO(3), and Na-acetate). The effect of the

  10. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil...

  11. Large-scale enzymatic production of natural flavour esters in organic solvent with continuous water removal.

    Science.gov (United States)

    Gubicza, L; Kabiri-Badr, A; Keoves, E; Belafi-Bako, K

    2001-11-30

    A new, large-scale process was developed for the enzymatic production of low molecular weight flavour esters in organic solvent. Solutions for the elimination of substrate and product inhibitions are presented. The excess water produced during the process was continuously removed by hetero-azeotropic distillation and esters were produced at yields of over 90%.

  12. Physical and mechanical testing of essential oil-embedded cellulose ester films

    Science.gov (United States)

    Polymer films made from cellulose esters are useful for embedding plant essential oils, either for food packaging or air freshener applications. Studies and testing were done on the physical and mechanical properties of cellulose ester-based films incorporating essential oils (EO) from lemongrass (C...

  13. Investigation of diesel-ethanol blended fuel properties with palm methyl ester as co-solvent and blends enhancer

    Directory of Open Access Journals (Sweden)

    Mat Taib Norhidayah

    2017-01-01

    Full Text Available Diesel engine is known as the most efficient engine with high efficiency and power but always reported as high fuel emission. Malaysia National Automotive Policy (NAP was targeting to improve competitive regional focusing on green technology development in reducing the emission of the engine. Therefore, ethanol was introduced to reduce the emission of the engine and while increasing its performance, Palm methyl ester was introduced as blend enhancer to improve engine performance and improve diesel-ethanol blends stability. This paper aimed to study the characteristics of the blends and to prove the ability of palm-methyl-ester as co-solvent in ethanol-diesel blends. Stability and thermophysical test were carried out for different fuel compositions. The stability of diesel-ethanol blended was proved to be improved with the addition of PME at the longer period and the stability of the blends changed depending on temperature and ethanol content. Density and viscosity of diesel-ethanol-PME blends also give higher result than diesel-ethanol blends and it's proved that PME is able to increase density and viscosity of blends. Besides, heating value of the blends also increases with the increasing PME in diesel-ethanol blends.

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

    Science.gov (United States)

    Hindryawati, Noor; Erwin, Maniam, Gaanty Pragas

    2017-02-01

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

  15. Carotenoids and Carotenoid Esters of Red and Yellow Physalis (Physalis alkekengi L. and P. pubescens L.) Fruits and Calyces.

    Science.gov (United States)

    Wen, Xin; Hempel, Judith; Schweiggert, Ralf M; Ni, Yuanying; Carle, Reinhold

    2017-08-02

    Carotenoid profiles of fruits and calyces of red (Physalis alkekengi L.) and yellow (P. pubescens L.) Physalis were characterized by HPLC-DAD-APCI-MS n . Altogether 69 carotenoids were detected in red Physalis, thereof, 45 were identified. In yellow Physalis, 40 carotenoids were detected and 33 were identified. Zeaxanthin esters with various fatty acids were found to be the most abundant carotenoids in red Physalis, accounting for 51-63% of total carotenoids, followed by β-cryptoxanthin esters (16-24%). In yellow Physalis, mainly free carotenoids such as lutein and β-carotene were found. Total carotenoid contents ranged between 19.8 and 21.6 mg/100 g fresh red Physalis fruits and 1.28-1.38 mg/100 g fresh yellow Physalis fruits, demonstrating that Physalis fruits are rich sources of dietary carotenoids. Yellow Physalis calyces contained only 153-306 μg carotenoids/g dry weight, while those of red Physalis contained substantially higher amounts (14.6-17.6 mg/g dry weight), thus possibly exhibiting great potential as a natural source for commercial zeaxanthin extraction.

  16. Estimated U.S. infant exposures to 3-MCPD esters and glycidyl esters from consumption of infant formula.

    Science.gov (United States)

    Spungen, Judith H; MacMahon, Shaun; Leigh, Jessica; Flannery, Brenna; Kim, Grace; Chirtel, Stuart; Smegal, Deborah

    2018-04-05

    A dietary exposure assessment was conducted for 3-monochloropropane-1,2-diol (3-MCPD) esters (3-MCPDE) and glycidyl esters (GE) in infant formulas available for consumption in the U.S. 3-MCPDE and GE are food contaminants generated during the deodorization of refined edible oils, which are used in infant formulas and other foods. 3-MCPDE and GE are of potential toxicological concern because these compounds are metabolized to free 3-MCPD and free glycidol in rodents, and may have the same metabolic fate in humans. Free 3-MCPD and free glycidol have been found to cause adverse effects in rodents. Dietary exposures to 3-MCPDE and GE from consumption of infant formulas are of particular interest because formulas are the sole or primary food source for some infants. In this analysis, U.S. Food and Drug Administration (FDA) data on 3-MCPDE and GE concentrations (as 3-MCPD and glycidol equivalents, respectively) in a small convenience sample of infant formulas were used to estimate exposures from consumption of formula by infants 0 - 6 months of age. 3-MCPDE and GE exposures based on mean concentrations in all formulas were estimated at 7 - 10 µg/kg bw/day and 2 µg/kg bw/day, respectively. Estimated mean exposures from consumption of formulas produced by individual manufacturers ranged from 1 - 14 µg/kg bw/day for 3-MCPDE, and from 1 - 3 µg/kg for GE.

  17. Critical aggregates concentration of fatty esters present in biodiesel determined by turbidity and fluorescence.

    Science.gov (United States)

    Froehner, Sandro; Sánez, Juan; Dombroski, Luiz Fernando; Gracioto, Maria Paula

    2017-09-01

    Biodiesel for combustible engine is available as mixture of fossil diesel and fatty esters obtained by transesterification of vegetable oils. The use of biodiesel reduces the amount of SO x , mainly. However, it was already observed that biodiesel has a different behavior in environment in cases of accidental spill and groundwater contamination. It was noticed that the biodegradation of hydrocarbons (cyclic and aliphatic) in the presence of biodiesel are speeded, although the mechanism is still unclear. Considering the chemical structure of fatty esters, it was investigated the formation of aggregates in water solution by fatty esters present in commercial biodiesel. In Brazil, biodiesel is composed by 95% of fossil diesel and 5% of fatty esters mixture. In this work, fatty esters were treated as neutral surfactant, i.e., it was treated as a molecule with polar and non-polar part. Turbidity and fluorescence were used to determine the critical aggregates concentration (CAC). Water solutions containing fatty esters were examined exploiting changes in turbidity and fluorescence intensity of pyrene. Abrupt changes were attributed to aggregates formation, following the same behavior of traditional amphiphilic compounds. It was determined the CAC for ethyl palmitate, ethyl stearate, ethyl oleate, and ethyl linoleate. The values of CAC for fatty esters varied from 1.91 to 4.27 μmol/L, while CAC for the mixture of esters (biodiesel) was 2.01 for methyl esters and 1.19 for ethyl esters, both prepared using soybean oil. The aggregates formation was also determined by fluorescence measurements considering the changes in intensity of peaks I and III of pyrene. Pyrene senses the changes in environment polarity. The values found of CAC by fluorescence for individual ethyl esters varied from 1.85 to 3.21 μmol/L, while mixtures of ethyl esters was 2.23 and 2.07 μmol/L for mixture of methyl esters. The results clearly showed that fatty esters form aggregates and might be

  18. Novel cellulose ester substrates for high performance flat-sheet thin-film composite (TFC) forward osmosis (FO) membranes

    KAUST Repository

    Ong, Rui Chin; Chung, Neal Tai-Shung; de Wit, Jos S.; Helmer, Bradley J.

    2015-01-01

    and seawater desalination with high performance. The performance of TFC-FO membranes prepared from the hydrophilic cellulose ester containing a high degree of OH and a moderate degree of Pr substitutions clearly surpasses those prepared from cellulose esters

  19. Decarbonylative Silylation of Esters by Combined Nickel and Copper Catalysis for the Synthesis of Arylsilanes and Heteroarylsilanes

    KAUST Repository

    Guo, Lin

    2016-08-25

    An efficient nickel/copper-catalyzed decarbonylative silylation reaction of carboxylic acid esters with silylboranes is described. This reaction provides access to structurally diverse silanes with high efficiency and excellent functional-group tolerance starting from readily available esters.

  20. Decarbonylative Silylation of Esters by Combined Nickel and Copper Catalysis for the Synthesis of Arylsilanes and Heteroarylsilanes

    KAUST Repository

    Guo, Lin; Chatupheeraphat, Adisak; Rueping, Magnus

    2016-01-01

    An efficient nickel/copper-catalyzed decarbonylative silylation reaction of carboxylic acid esters with silylboranes is described. This reaction provides access to structurally diverse silanes with high efficiency and excellent functional-group tolerance starting from readily available esters.

  1. Sinapate esters provide greater UV-B attenuation than flavonoids in Arabidopsis thaliana (Brassicaceae)

    International Nuclear Information System (INIS)

    Sheahan, J.J.

    1996-01-01

    Mutants affected in flavonoid (tt4) or sinapate ester (fah1) biosynthesis were used to assess the relative importance of these phenolic UV photoprotectants in Arabidopsis. Flavonoid and sinapate ester absorption was more specific for UV-B than major nonphenolic chromophores in crude extracts. A new method of evaluating phenolic UV-B attenuation was developed using fluorescence analysis. When excited by UV-B, sinapate ester containing leaves and cotyledons had enhanced sinapate ester fluorescence and reduced chlorophyll fluorescence relative to those without sinapate esters. Although fluorescence analysis gave no evidence of UV-B attenuation by flavonoids, enhanced chlorophyll and protein loss were observed upon UV-B exposure in flavonoid-deficient leaves, suggesting they have another mechanism of UV-B protection. The hydroxycinnamates have been largely ignored as UV-B attenuating pigments. and the results indicate that greater attention should be paid to their role in attenuating UV-B

  2. Development of tartaric esters as bifunctional additives of methanol-gasoline.

    Science.gov (United States)

    Zhang, Jie; Yang, Changchun; Tang, Ying; Zhou, Rui; Wang, Xiaoli; Xu, Lianghong

    2014-01-01

    Methanol has become an alternative fuel for gasoline, which is facing a rapidly rising world demand with a limited oil supply. Methanol-gasoline has been used in China, but phase stability and vapor lock still need to be resolved in methanol-gasoline applications. In this paper, a series of tartaric esters were synthesized and used as phase stabilizers and saturation vapor pressure depressors for methanol-gasoline. The results showed that the phase stabilities of tartaric esters for methanol-gasoline depend on the length of the alkoxy group. Several tartaric esters were found to be effective in various gasoline-methanol blends, and the tartaric esters display high capacity to depress the saturation vapor pressure of methanol-gasoline. According to the results, it can be concluded that the tartaric esters have great potential to be bifunctional gasoline-methanol additives.

  3. Synthesis and Analysis of Methacryloyl-L-Alanine Methyl Ester using fourier Transform Nuclear Magnetic Resonance

    International Nuclear Information System (INIS)

    Tri Darwinto

    2008-01-01

    Methacryloyl-L-alanine methyl ester was synthesized by reacting methacrylic acid with L-alanine methyl ester hydrochloride in triethylamine at temperature of 90 o C. Hydrogel polymer of poly(methacryloyl-L-alanine methyl ester) was much used for diagnosis and therapy of vascular tumor. The molecular structure methacryloyl-L-alanine methyl ester analyzed by fourier transform nuclear magnetic resonance (FT-NMR) for analyzing of carbon atom ( 13 C) using Distortionless Enhancement by Polarization Transfer (DEPT) measurement mode with coupling as well as without coupling from proton atom ( 1 H). Molecular structure analysis result showed that DEPT FT-NMR measurement mode with coupling as well as without coupling from 1 H was very fast, exact and accurate method for molecular analysis of organic compound especially methacryloyl-L-alanine methyl ester. (author)

  4. Anti-oedematous activities of the main triterpendiol esters of marigold (Calendula officinalis L.).

    Science.gov (United States)

    Zitterl-Eglseer, K; Sosa, S; Jurenitsch, J; Schubert-Zsilavecz, M; Della Loggia, R; Tubaro, A; Bertoldi, M; Franz, C

    1997-07-01

    Separation and isolation of the genuine faradiol esters (1, 2) from flower heads of Marigold (Calendula (officinalis L., Asteraceae) could be achieved by means of repeated column chromatography (CC) and HPLC for the first time. Structure elucidation of faradiol-3-myristic acid ester 1, faradiol-3-palmitic acid ester 2 and psi-taraxasterol 3 has been also performed, without any previous degradation by means of MS, 1H-NMR, 13C-NMR and 2D-NMR experiments. The anti-oedematous activities of these three compounds were tested by means of inhibition of Croton oil-induced oedema of the mouse ear. Both faradiol esters showed nearly the same dose dependent anti-oedematous activity and no significant synergism appeared with their mixture. The free monol, psi-taraxasterol, had a slightly lower effect. Furthermore, faradiol was more active than its esters and than psi-taraxasterol and showed the same effect as an equimolar dose of indomethacin.

  5. Palladium-Catalyzed ortho-Olefination of Phenyl Acetic and Phenyl Propylacetic Esters via C-H Bond Activation.

    Science.gov (United States)

    Hu, Jundie; Guan, Mingyu; Han, Jian; Huang, Zhi-Bin; Shi, Da-Qing; Zhao, Yingsheng

    2015-08-21

    A highly regioselective palladium-catalyzed ester-directed ortho-olefination of phenyl acetic and propionic esters with olefins via C-H bond activation has been developed. A wide variety of phenyl acetic and propionic esters were tolerated in this transformation, affording the corresponding olefinated aromatic compounds. The ortho-olefination of heterocyclic acetic and propionic esters also took place smoothly giving the products in good yields, thus proving the potential utility of this protocol in synthetic chemistry.

  6. Tropanol esters of metallocene carboxylic acids. Syntheses, labelling with 103Ru and sup(103m)Rh and organ distribution

    International Nuclear Information System (INIS)

    Wenzel, M.; Wu, Y.

    1988-01-01

    The tropanol esters of the carboxylic acids of ferrocene, 103 Ru-ruthenocene and sup(103m)Rh-rhodocinium were synthezised. The organ distribution of the 103 Ru or sup(103m)Rh labelled tropanol-esters were investigated. Only the 103 Ru labelled ester showed a high heart/blood ratio. (author)

  7. 21 CFR 172.225 - Methyl and ethyl esters of fatty acids produced from edible fats and oils.

    Science.gov (United States)

    2010-04-01

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

  8. 75 FR 20785 - Polyglyceryl Phthalate Ester of Coconut Oil Fatty Acids; Exemption from the Requirement of a...

    Science.gov (United States)

    2010-04-21

    ... Phthalate Ester of Coconut Oil Fatty Acids; Exemption from the Requirement of a Tolerance; Technical... ester of coconut oil fatty acids; exemption from the requirement of a tolerance. This document is being... requirement of a tolerance for ``polyglyceryl phthalate ester of coconut oil fatty acids'' pursuant to a...

  9. Cell killing and radiosensitization by caffeic acid phenethyl ester (CAPE) in lung cancer cells

    International Nuclear Information System (INIS)

    Chen, Miao-Fen; Chen, Wen-Cheng; Wu, Chun-Te; King, P.C.

    2004-01-01

    Caffeic acid phenethyl ester (CAPE) is a biologically active ingredient of honeybee propoplis. The cytotoxicity and radiation sensitization effects of CAPE were evaluated in human lung cancer A549 cells and normal lung fibroblast WI-38 cells. A549 cells treated with 6 μg/ml CAPE showed marked growth inhibition (60%) at 48 hr after treatments. During the same time, the number of viable cells decreased to 46% of the control value. In contrast, WI-38 cells showed 20% growth inhibition with no change in the number of viable cells under the same treatment conditions. At 72 hr after CAPE treatment (6 μg/ml), the percentage of apoptotic cells in A549 cultures increased significantly to 67% and an S/G2 arrest was also detected in the culture. Furthermore, there was a significant decrease in the level of intracellular glutathione and hydrogen peroxide contents within one hr after CAPE treatment, and the expression of cyclin B 1 was reduced 6 hr after treatment. The radiation sensitization effect of CAPE on A549 cells was determined from the clonogenic survival curves, and the results showed a small but significant difference in radiation survival between cells treated with or without CAPE. Taken together, our results suggest that the effects of CAPE on differential cytotoxicity, apoptosis, and radiosensitization are associated with glutathione depletion that occurred shortly after treatments. (author)

  10. Nonaqueous gel for the transdermal delivery of a DTPA penta-ethyl ester prodrug.

    Science.gov (United States)

    Zhang, Yong; Sadgrove, Matthew P; Sueda, Katsuhiko; Yang, Yu-Tsai; Pacyniak, Erik K; Kagel, John R; Braun, Brenda A; Zamboni, William C; Mumper, Russell J; Jay, Michael

    2013-04-01

    Diethylenetriamine pentaacetic acid penta-ethyl ester, designated as C2E5, was successfully incorporated into a nonaqueous gel for transdermal delivery. The thermal and rheological properties of a formulation containing 40% C2E5, 20% ethyl cellulose, and 40% Miglyol 840® prepared using the solvent evaporation method demonstrated that the gel had acceptable content uniformity and flow properties. In vitro studies showed that C2E5 was steadily released from the gel at a rate suitable for transdermal delivery. Topical application of the gel at a 200 mg C2E5/kg dose level in rats achieved significantly higher plasma exposures of several active metabolites compared with neat C2E5 oil at the same dose level. The results suggest that transdermal delivery of a chelator prodrug is an effective radionuclide decorporation strategy by delivering chelators to the circulation with a pharmacokinetic profile that is more consistent with the biokinetic profile of transuranic elements in contaminated individuals.

  11. INFLUENCE OF PALM METHYL ESTER (PME AS AN ALTERNATIVE FUEL IN MULTICYLINDER DIESEL ENGINE

    Directory of Open Access Journals (Sweden)

    Mohd Hafizil M. Yasin

    2012-12-01

    Full Text Available Palm oil is one of the vegetable oil, which is converted to biodiesel through a transesterification process using methanol as the catalyst. Palm oil biodiesel or palm methyl ester (PME can be used in diesel engines without any modification, and can be blended with conventional diesel to produce different proportions of PME-diesel blend fuels. The physical properties of PME were evaluated experimentally and theoretically. The effect of using neat PME as fuel on engine performance and emissions was evaluated using a commercial four-cylinder four-stroke IDI diesel engine. The experimental results on an engine operated with PME exhibited higher brake specific fuel consumption in comparison with the conventional fuel. With respect to the in-cylinder pressure and heat release rate, these increased features by over 8.11% and 9.3% with PME compared to conventional diesel. The overall results show that PME surpassed the diesel combustion quality due to its psychochemical properties and higher oxygen content.

  12. Characteristics of Oxidative Storage Stability of Canola Fatty Acid Methyl Ester Stabilised with Antioxidants

    Directory of Open Access Journals (Sweden)

    Tirto Prakoso

    2012-11-01

    Full Text Available The storage effects on the oxidation characteristics of fatty acid methyl ester of canola oil (CME were investigated in this study. CME stabilised with two antioxidants, i.e. 2,6-di-tert-bytyl-p-cresol (BHT and 6,6-di-tert-butyl-2, 2’-methylendi-p-cresol (BPH, was stored at 20, 40 and 60°C. The oxidation stability data were measured by the Rancimat test method and it was found that both BHT and BPH addition increased the oxidation resistance of the CME. The results showed that when BPH or BHT was added at a concentration of 100 ppm, the oxidation induction period of the neat CME samples increased from 5.53 h to 6.93 h and 6.14 h, respectively. Comparing both antioxidants, BPH proved to be more effective in increasing the oxidation resistance when both antioxidants were added at the same concentration. Furthermore, the oxidation induction time decreased linearly with the storage time. It was shown that the oxidation occurred rapidly in the first 8 weeks of storage. Later, a kinetic study was undertaken and first-order kinetics were applied to explain the oxidation characteristics of the CME added with antioxidants. This kinetic study focused on exploiting the activation energy values obtained from the Arrhenius equations. Also, the oxidation effects on other quality parameters, including acid value, peroxide value, kinematic viscosity, and water content, were examined.

  13. [Inhibition of oxidation of unsaturated fatty acid methyl esters by essential oils].

    Science.gov (United States)

    Misharina, T A; Alinkina, E S; Vorobjeva, A K; Terenina, M B; Krikunova, N I

    2016-01-01

    The essential oils from 16 various spice plants were studied as natural antioxidants for the inhibition of autooxidation of polyunsaturated fatty acids methyl esters isolated from linseed oil. The content of methyl oleate, methyl linoleate, and methyl linolenoate after 1, 2, and 4 months of autooxidation were used as criteria to estimate the antioxidant efficiencies of essential oils. In 4 months, 92% of the methyl linolenoate and 79% of the methyl linoleate were oxidized in a control sample of a model system. It was found that the most effective antioxidants were essential oils from clove bud, cinnamon leaves, and oregano. They inhibited autooxidation of methyl linolenoate by 76–85%. The antioxidant properties of these essential oils were due to phenols— eugenol, carvacrol, and thymol. Essential oil from coriander did not contain phenols, but it inhibited methyl linolenoate oxidation by 38%. Essential oils from thyme, savory, mace, lemon, and tea tree inhibited methyl linolenoate oxidation by 17–24%. The other essential oils had no antioxidant properties.

  14. Relative oral bioavailability of 3-MCPD from 3-MCPD fatty acid esters in rats.

    Science.gov (United States)

    Abraham, Klaus; Appel, Klaus E; Berger-Preiss, Edith; Apel, Elisabeth; Gerling, Susanne; Mielke, Hans; Creutzenberg, Otto; Lampen, Alfonso

    2013-04-01

    In order to quantify the relative oral bioavailability of 3-chloropropane-1,2-diol (3-MCPD) from 3-MCPD fatty acid diesters in vivo, 1,2-dipalmitoyl-3-chloropropane-1,2-diol (3-MCPD diester) and 3-MCPD were orally applied to rats in equimolar doses. In both cases, the time courses of 3-MCPD concentrations were measured in blood, various organs, tissues and intestinal luminal contents. The results show that 3-MCPD is released by enzymatic hydrolysis from the 3-MCPD diester in the gastrointestinal tract and distributed to blood, organs and tissues. Based on the measurements in blood, the areas under the curve (AUC) for 3-MCPD were calculated. By comparing both AUC, the relative amount of 3-MCPD bioavailable from the 3-MCPD diester was calculated to be 86 % on average of the amount bioavailable following administration of 3-MCPD. In view of limited experimental data, it is justified for the purpose of risk assessment to assume complete hydrolysis of the diesters in the gastro-intestinal tract. Therefore, assessment of the extent of exposure to 3-MCPD released from its fatty acid esters should be performed in the same way as exposure to the same molar quantity of 3-MCPD.

  15. Conversion of Oleum papaveris seminis oil into methyl esters via esterification process optimization and kinetic study

    Energy Technology Data Exchange (ETDEWEB)

    Syam, A.M.; Rashid, U.; Yunus, R.; Hamid, H.A.; Al-Resayes, S.I.; Nehdi, I.A.; Al-Muhtaseb, A.H.

    2016-07-01

    This paper presents an acid pre-treatment process and a kinetic study for the esterification reaction of Oleum papaveris seminis oil with methanol in the presence of amberlite 120 as a solid catalyst to convert the oil into methyl esters. Response surface methodology (RSM) was applied to optimize the reaction parameters, i.e. reaction time, percentage of the catalyst and volume ratio of methanol to oil. The results revealed that 0.87% w/w of catalyst concentration and 44.70% v/v of methanol to oil ratio provided final free fatty acid (FFA) contents of 0.60% w/w at 102.40 min of reaction time. It proved that the contribution of Amberlite 120 in the esterification of FFA was highly significant. The kinetics of the esterification in Oleum papaveris seminis oil with methanol in the presence of the amberlite 120 catalyst were also investigated to establish the reaction rate constant (k), reaction order, and activation energy. The study was performed under the optimized parameters at three reaction temperatures (50, 55, and 60 ºC). The value of k was in the range of 0.013 to 0.027 min-1. The first-order kinetics’ model was suitable for this irreversible FFA esterification with the activation energy of about 60.9 KJ·mol-1. (Author)

  16. Antiwear and antioxidant studies of cardanol phosphate ester additives

    Energy Technology Data Exchange (ETDEWEB)

    Mazzetto, S.E.; Oliveira, L.D.M.; Lomonaco, D.; Veloso, P.A., E-mail: selma@ufc.br [Lab. de Produtos e Tecnologia em Processos (LPT), Dept. de Quimica Organica e Inorganica, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

    2012-07-15

    In the search for new applications and products derived from Cashew Nut Shell Liquid (CNSL), we report herein the synthesis and characterization (GC/MS and {sup 1}H, {sup 13}C, and {sup 31}P NMR) of four phosphate esters derived from hydrogenated cardanol, including their applications as antiwear additives for diesel (S500) and as antioxidant additives for mineral oils, evaluated through the HFRR test and oxidative stability analyses, respectively. The results obtained showed very good to excellent performances promoted by the bioadditives evaluated, especially for the thiophosphorylated derivative, which notably reduced the sludge residue and the acidity index of the oxidized oil (0.52 mg NaOH/g sample) and also improved the diesel lubricity, reducing the wear of metal parts by more than 50% (330 {Mu}m). Keywords: Cardanol; Antiwear; Antioxidant; Diesel; Mineral oil. (author)

  17. Three new triterpene esters from pumpkin (Cucurbita maxima) seeds.

    Science.gov (United States)

    Kikuchi, Takashi; Ueda, Shinsuke; Kanazawa, Jokaku; Naoe, Hiroki; Yamada, Takeshi; Tanaka, Reiko

    2014-04-16

    Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1), 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2), and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3), were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11)-diene-3α,29-diol 3,29-dibenzoate (4). Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5-93.7 μM against HL-60 and P388 cells.

  18. Three New Triterpene Esters from Pumpkin (Cucurbita maxima Seeds

    Directory of Open Access Journals (Sweden)

    Takashi Kikuchi

    2014-04-01

    Full Text Available Three new multiflorane-type triterpene esters, i.e. 7α-hydroxymultiflor-8-ene-3α,29-diol 3-acetate-29-benzoate (1, 7α-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (2, and 7β-methoxymultiflor-8-ene-3α,29-diol 3,29-dibenzoate (3, were isolated from seeds of Cucurbita maxima, along with the known compound, multiflora-7,9(11-diene-3α,29-diol 3,29-dibenzoate (4. Compound 1 exhibited melanogenesis inhibitory activities comparable with those of arbutin. In cytotoxicity assays, compounds 1 and 3 exhibited weak cytotoxicity, with IC50 values of 34.5–93.7 μM against HL-60 and P388 cells.

  19. Spectroscopic investigation of degradation of rapseed oil methyl esters

    International Nuclear Information System (INIS)

    Kampars, V.

    2003-01-01

    Investigation of rapseed oil methyl esters by US VIS and FTIR spectroscopy during the heating at 80 deg C were carried out. The degradation begins immediately after beginning of experiment. The main process at first stage is destroying of carotenoids and oxidation of polyunsaturated fatty acids by forming conjugated polyenes. Between the formation of conjugated triens and destroying of carotenoids exist definite interconnection, but there isn't evidence for the protective activity of carotenoids. As follows from FTIR spectroscopy the increase of carbonyl compounds concentration begins immediately after the start of experiment and continues all the time. Despite to the complex character the peak at 220 nm is only one spectroscopic characteristic with a sharp alteration point and may be used for the fast and simple detection of storage stability of bio diesels. (authors)

  20. Post surgical pain management with poly(ortho esters).

    Science.gov (United States)

    Barr, John; Woodburn, Kathryn W; Ng, Steven Y; Shen, Hui-Rong; Heller, Jorge

    2002-10-16

    Poly(ortho esters), POE, are synthetic bioerodible polymers that can be prepared as solid materials, or as viscous, injectable polymers. These materials have evolved through a number of families, and the latest member of this family, POE IV, is particularly well suited to drug delivery since latent acid is integrated into the polymer backbone, thereby, modulating surface erosion. POE IV predominantly undergoes surface erosion and is able to moderate drug release over periods from days to many months. One indication in which the POE IV polymer is currently being investigated is in sustained post-surgical pain management. The local anesthetic agent, mepivacaine, has been incorporated into a viscous, injectable POE IV and its potential to provide longer-acting anesthesia has been explored in non-clinical models.

  1. Phthalic acid esters found in municipal organic waste

    DEFF Research Database (Denmark)

    Hartmann, Hinrich; Ahring, Birgitte Kiær

    2003-01-01

    Contamination of the organic fraction of municipal solid waste (OFMSW) with xenobiotic compounds and their fate during anaerobic digestion was investigated. The phthalic acid ester di-(2- ethylhexyl)phthalate (DEHP) was identified as the main contaminant in OFMSW in concentrations more than half.......41-0.79 d(-1), which is much higher than in previous investigations. It can be concluded that the higher removal rates are due to the higher temperature and higher initial concentrations per kg dry matter. These results suggest that the limiting factor for DEHP degradation is the bioavailability, which...... is enhanced at higher temperature and higher degradation of solid organic matter, to which the highly hydrophobic DEHP is adsorbed. The investigated reactor configuration with a thermophilic and a hyper-thermophilic treatment is, therefore, a good option for CD combining high rate degradation of organic...

  2. Activities of Jatropha curcas phorbol esters in various bioassays.

    Science.gov (United States)

    Devappa, Rakshit K; Rajesh, Sanjay K; Kumar, Vikas; Makkar, Harinder P S; Becker, Klaus

    2012-04-01

    Jatropha curcas seeds contain 30-35% oil, which can be converted to high quality biodiesel. However, Jatropha oil is toxic, ascribed to the presence of phorbol esters (PEs). In this study, isolated phorbol ester rich fraction (PEEF) was used to evaluate the activity of PEs using three aquatic species based bioassays (snail (Physa fontinalis), brine shrimp (Artemeia salina), daphnia (Daphnia magna)) and microorganisms. In all the bioassays tested, increase in concentration of PEs increased mortality with an EC(50) (48 h) of 0.33, 26.48 and 0.95 mg L(-1) PEs for snail, artemia and daphnia, respectively. The sensitivity of various microorganisms for PEs was also tested. Among the bacterial species tested, Streptococcus pyogenes and Proteus mirabilis were highly susceptible with a minimum inhibitory concentration (MIC) of 215 mg L(-1) PEs; and Pseudomonas putida were also sensitive with MIC of 251 mg L(-1) PEs. Similarly, Fusarium species of fungi exhibited EC(50) of 58 mg L(-1) PEs, while Aspergillus niger and Curvularia lunata had EC(50) of 70 mg L(-1). The snail bioassay was most sensitive with 100% snail mortality at 1 μg of PEs mL(-1). In conclusion, snail bioassay could be used to monitor PEs in Jatropha derived products such as oil, biodiesel, fatty acid distillate, kernel meal, cake, glycerol or for contamination in soil or other environmental matrices. In addition, PEs with molluscicidal/antimicrobial activities could be utilized for agricultural and pharmaceutical applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Effects of phthalic acid esters on the liver and thyroid

    International Nuclear Information System (INIS)

    Hinton, R.H.; Mitchell, F.E.; Mann, A.; Chescoe, D.; Price, S.C.; Nunn, A.; Grasso, P.; Bridges, J.W.

    1986-01-01

    The effects, over periods from 3 days to 9 months of administration, of diets containing di-2-ethylhexyl phthalate are very similar to those observed in rats administered diets containing hypolipidemic drugs such as clofibrate. Changes occur in a characteristic order commencing with alterations in the distribution of lipid within the liver, quickly followed by proliferation of hepatic peroxisomes and induction of the specialized P-450 isoenzyme(s) catalyzing omega oxidation of fatty acids. There follows a phase of mild liver damage indicated by changes in incorporation of 3 H-thymidine into DNA, by induction of glucose-6-phosphatase activity and a loss of glycogen, eventually leading to the formation of enlarged lysosomes through autophagy and the accumulation of lipofuscin. Associated changes are found in the kidney and thyroid. The renal changes are limited to the proximal convoluted tubules and are generally similar to changes found in the liver. The effects on the thyroid are more marked. Although the levels of thyroxine in plasma fall to about half normal values, serum triiodothyronine remains close to normal values while the appearance of the thyroid varies, very marked hyperactivity being noted 7 days after commencement of treatment, this is less marked at 14 days, but even after 9 months treatment there is clear cut evidence for hyperactivity with colloid changes which indicate this has persisted for some time. The short-term in vivo hepatic effects of the three phthalate esters can be reproduced in hepatocytes in tissue culture. All three phthalate esters, as well as clofibrate, have early marked effects on the metabolism of fatty acids in isolated hepatocytes. A hypothesis is presented to explain the progress from these initial metabolic effects to the final formation of liver tumors

  4. Improving the Cold Temperature Properties of Tallow-Based Methyl Ester Mixtures Using Fractionation, Blending, and Additives

    Science.gov (United States)

    Elwell, Caleb

    Beef tallow is a less common feedstock source for biodiesel than soy or canola oil, but it can have economic benefits in comparison to these traditional feedstocks. However, tallow methyl ester (TME) has the major disadvantage of poor cold temperature properties. Cloud point (CP) is an standard industry metric for evaluating the cold temperature performance of biodiesel and is directly related to the thermodynamic properties of the fuel's constituents. TME has a CP of 14.5°C compared with 2.3°C for soy methyl ester (SME) and -8.3°C for canola methyl ester (CME). In this study, three methods were evaluated to reduce the CP of TME: fractionation, blending with SME and CME, and using polymer additives. TME fractionation (i.e. removal of specific methyl ester constituents) was simulated by creating FAME mixtures to match the FAME profiles of fractionated TME. The fractionation yield was found to be highest at the eutectic point of methyl palmitate (MP) and methyl stearate (MS), which was empirically determined to be at a MP/(MP+MS) ratio of approximately 82%. Since unmodified TME has a MP/(MP+MS) ratio of 59%, initially only MS should be removed to produce a ratio closer to the eutectic point to reduce CP and maximize yield. Graphs relating yield (with 4:1 methyl stearate to methyl oleate carryover) to CP were produced to determine the economic viability of this approach. To evaluate the effect of blending TME with other methyl esters, SME and CME were blended with TME at blend ratios of 0 to 100%. Both the SME/TME and CME/TME blends exhibited decreased CPs with increasing levels of SME and CME. Although the CP of the SME/TME blends varied linearly with SME content, the CP of the CME/TME blends varied quadratically with CME content. To evaluate the potential of fuel additives to reduce the CP of TME, 11 different polymer additives were tested. Although all of these additives were specifically marketed to enhance the cold temperature properties of petroleum diesel or

  5. The morphology and phase mixing studies on poly(ester urethane) during a low temperature shape memory cycle

    International Nuclear Information System (INIS)

    Pereira, I.M.; Orefice, R.L.

    2009-01-01

    Three series of low molecular weight shape memory poly(ester-urethane) with varying hard-segment content were synthesized. The materials were designed to display a three-phase structure consisting of a disperse phase formed by crystallites and hard domains embedded in an amorphous matrix. The structure and thermal properties were investigated using techniques such as: modulated differential scanning calorimetry, dynamic mechanical analysis and small angle X-ray scattering. The results were associated with the morphological changes observed during a low temperature shape-memory cycle. The recover was observed to be triggered by the melting of the crystallites and by the strong interactions among hard domains. Temporary shape was stored by the metastable structure formed during deformation. (author)

  6. Fatty acid esters-based composite phase change materials for thermal energy storage in buildings

    International Nuclear Information System (INIS)

    Sarı, Ahmet; Karaipekli, Ali

    2012-01-01

    In this study, fatty acid esters-based composite phase change materials (PCMs) for thermal energy storage were prepared by blending erythritol tetrapalmitate (ETP) and erythritol tetrastearate (ETS) with diatomite and expanded perlite (EP). The maximum incorporation percentage for ETP and ETS into diatomite and EP was found to be 57 wt% and 62 wt%, respectively without melted PCM seepage from the composites. The morphologies and compatibilities of the composite PCMs were structurally characterized using scanning electron microscope (SEM) and Fourier transformation infrared (FT–IR) analysis techniques. Thermal energy storage properties of the composite PCMs were determined by differential scanning calorimetry (DSC) analysis. The DSC analyses results indicated that the composite PCMs were good candidates for building applications in terms of their large latent heat values and suitable phase change temperatures. The thermal cycling test including 1000 melting and freezing cycling showed that composite PCMs had good thermal reliability and chemical stability. TG analysis revealed that the composite PCMs had good thermal durability above their working temperature ranges. Moreover, in order to improve the thermal conductivity of the composite PCMs, the expanded graphite (EG) was added to them at different mass fractions (2%, 5%, and 10%). The best results were obtained for the composite PCMs including 5wt% EG content in terms of the increase in thermal conductivity values and the decrease amount in latent heat capacity. The improvement in thermal conductivity values of ETP/Diatomite, ETS/Diatomite, ETP/EP and ETS/EP were found to be about 68%, 57%, 73% and 75%, respectively. Highlights: ► Fatty acid esters-based composite PCMs were prepared by blending ETP and ETS with diatomite and expanded perlite. ► The composite PCMs were characterized by using SEM, FT–IR, DSC and TG analysis methods. ► The DSC results indicated that the composites PCMs had good thermal

  7. Short-chain flavor ester synthesis in organic media by an E. coli whole-cell biocatalyst expressing a newly characterized heterologous lipase.

    Directory of Open Access Journals (Sweden)

    Guillaume Brault

    Full Text Available Short-chain aliphatic esters are small volatile molecules that produce fruity and pleasant aromas and flavors. Most of these esters are artificially produced or extracted from natural sources at high cost. It is, however, possible to 'naturally' produce these molecules using biocatalysts such as lipases and esterases. A gene coding for a newly uncovered lipase was isolated from a previous metagenomic study and cloned into E. coli BL21 (DE3 for overexpression using the pET16b plasmid. Using this recombinant strain as a whole-cell biocatalyst, short chain esters were efficiently synthesized by transesterification and esterification reactions in organic media. The recombinant lipase (LipIAF5-2 showed good affinity toward glyceryl trioctanoate and the highest conversion yields were obtained for the transesterification of glyceryl triacetate with methanol. Using a simple cetyl-trimethylammonium bromide pretreatment increased the synthetic activity by a six-fold factor and the whole-cell biocatalyst showed the highest activity at 40°C with a relatively high water content of 10% (w/w. The whole-cell biocatalyst showed excellent tolerance to alcohol and short-chain fatty acid denaturation. Substrate affinity was equally effective with all primary alcohols tested as acyl acceptors, with a slight preference for methanol. The best transesterification conversion of 50 mmol glyceryl triacetate into isoamyl acetate (banana fragrance provided near 100% yield after 24 hours using 10% biocatalyst loading (w/w in a fluidized bed reactor, allowing recycling of the biocatalyst up to five times. These results show promising potential for an industrial approach aimed at the biosynthesis of short-chain esters, namely for natural flavor and fragrance production in micro-aqueous media.

  8. Multimedia content classification metrics for content adaptation

    OpenAIRE

    Fernandes, Rui; Andrade, M.T.

    2015-01-01

    Multimedia content consumption is very popular nowadays. However, not every content can be consumed in its original format: the combination of content, transport and access networks, consumption device and usage environment characteristics may all pose restrictions to that purpose. One way to provide the best possible quality to the user is to adapt the content according to these restrictions as well as user preferences. This adaptation stage can be best executed if knowledge about the conten...

  9. Multimedia content classification metrics for content adaptation

    OpenAIRE

    Fernandes, Rui; Andrade, M.T.

    2016-01-01

    Multimedia content consumption is very popular nowadays. However, not every content can be consumed in its original format: the combination of content, transport and access networks, consumption device and usage environment characteristics may all pose restrictions to that purpose. One way to provide the best possible quality to the user is to adapt the content according to these restrictions as well as user preferences. This adaptation stage can be best executed if knowledge about the conten...

  10. Restorative Effects of Caffeic Acid Phenethyl Ester in Radiation-Induced Oxidative Hepatic Disorders

    International Nuclear Information System (INIS)

    El-Fatih, N.M.; EI-Tawil, G.A.

    2009-01-01

    The potential role of antioxidant natural phenolic compounds in the prevention of oxidative tissue-damage associated with ionizing-radiation has accumulated over the past decades. The possible restorative effect of caffeic acid phenethyl ester (CAPE) in minimizing radiation-induced hepatic injury in male albino rats was investigated. CAPE was given to rats via intraperitoneal (ip.) injection at a dose of (10μmol/ kg b.wt.) for 21 successive days throughout exposure to gamma radiation and continued for 15 successive days post gamma-radiation exposure. Whole body gamma-irradiation was delivered as fractionated doses (3 weeks) 2 Gy increment every week up to total cumulative dose of G Gy. Rats were sacrificed at either I, or 15 days after last dose of radiation. Malondialdehyde (MDA) content was determined in plasma and hepatic tissues. In addition, the activities of xanthine oxidase (XO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) as well as the level of reduced glutathione (GSH) were determined to evaluate the changes of antioxidant-status in blood systems and hepatic tissues. Meantime, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activities were estimated in rat serum. Results showed that exposure to gamma-radiation significantly increased the MDA levels and the activities of XO, ALT, AST and ALP. Moreover, SOD, CAT and GSH-Px activities as well GSH contents showed significant consumption in irradiated rats. Treatment with CAPE showed a significant decrease in MDA level and caused significant increases in all enzymes measured in hepatic tissues and blood systems when compared with irradiated group. Conclusion: radiation-exposure leads to a reduction in antioxidant enzymatic activities and causes lipid peroxidation in hepatic tissues and blood. Under experimental condition, CAPE exhibits restorative effects on gamma-rays-induced hepatic-oxidative impairment in rats

  11. Restorative Effects of Caffeic Acid Phenethyl Ester in Radiation-Induced Oxidative Hepatic Disorders

    International Nuclear Information System (INIS)

    El-Fatih, N.M.; EI-Tawil, G.A.

    2008-01-01

    The potential role of antioxidant natural phenolic compounds in the prevention of oxidative tissue-damage associated with ionizing-radiation has accumulated over the past decades. The possible restorative effect of caffeic acid phenethyl ester (CAPE) in minimizing radiation-induced hepatic injury in male albino rats was investigated. CAPE was given to rats via intraperitoneal (ip.) injection at a dose of (10μmol/ kg b.wt.) for 21 successive days throughout exposure to gamma radiation and continued for 15 successive days post gamma-radiation exposure. Whole body gamma-irradiation was delivered as fractionated doses (3 weeks) 2 Gy increment every week up to total cumulative dose of G Gy. Rats were sacrificed at either I, or 15 days after last dose of radiation. Malondialdehyde (MDA) content was determined in plasma and hepatic tissues. In addition, the activities of xanthine oxidase (XO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) as well as the level of reduced glutathione (GSH) were determined to evaluate the changes of antioxidant-status in blood systems and hepatic tissues. Meantime, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activities were estimated in rat serum. Results showed that exposure to gamma-radiation significantly increased the MDA levels and the activities of XO, ALT, AST and ALP. Moreover, SOD, CAT and GSH-Px activities as well GSH contents showed significant consumption in irradiated rats. Treatment with CAPE showed a significant decrease in MDA level and caused significant increases in all enzymes measured in hepatic tissues and blood systems when compared with irradiated group. Conclusion: radiation-exposure leads to a reduction in antioxidant enzymatic activities and causes lipid peroxidation in hepatic tissues and blood. Under experimental condition, CAPE exhibits restorative effects on gamma-rays-induced hepatic-oxidative impairment in rats

  12. Simultaneous microwave extraction and synthesis of fatty acid methyl ester from the oleaginous yeast Rhodotorula glutinis

    International Nuclear Information System (INIS)

    Chuck, Christopher J.; Lou-Hing, Daniel; Dean, Rebecca; Sargeant, Lisa A.; Scott, Rod J.; Jenkins, Rhodri W.

    2014-01-01

    Microbial lipids have the potential to substantially reduce the use of liquid fossil fuels, though one obstacle is the energy costs associated with the extraction and subsequent conversion into a biofuel. Here we report a one-step method to produce FAME (fatty acid methyl esters) from Rhodotorula glutinis by combining lipid extraction in a microwave reactor with acid-catalysed transesterification. The microwave did not alter the FAME profile and over 99% of the lipid was esterified when using 25 wt% H 2 SO 4 over 20 min at 120 °C. On using higher loadings of catalyst, similar yields were achieved over 30 s. Equivalent amounts of FAME were recovered in 30 s using this method as with a 4 h Soxhlet extraction, run with the same solvent system. When water was present at less than a 1:1 ratio with methanol, the main product was FAME, above this the major products were FFA (free fatty acids). Under the best conditions, the energy required for the microwave was less than 20% of the energy content of the biodiesel produced. Increasing the temperature did not change the EROI (energy return on investment) substantially; however, longer reaction times used an equivalent amount of energy to the total energy content of the biodiesel. - Highlights: • The extraction and transesterification of yeast lipid were achieved using a microwave reactor. • The lipid was extracted from Rhodotorula glutinis within 30 s under all conditions. • Addition of 25 wt% H 2 SO 4 catalyst converted 95% glycerides to FAME over 5 min. • Water could be tolerated up to 25 wt% without high FFA production. • The temperature of the microwave had less impact on EROI than the length of extraction

  13. Optimal Use of Plant Stanol Ester in the Management of Hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Susanna Rosin

    2015-01-01

    Full Text Available Plant stanol ester is a natural compound which is used as a cholesterol-lowering ingredient in functional foods and food supplements. The safety and efficacy of plant stanol ester have been confirmed in more than 70 published clinical studies and the ingredient is a well-established and widely recommended dietary measure to reduce serum cholesterol. Daily intake of 2 g plant stanols as plant stanol ester lowers LDL-cholesterol by 10%, on average. In Europe, foods with added plant stanol ester have been on the market for 20 years, and today such products are also available in many Asian and American countries. Despite the well-documented efficacy, the full potential in cholesterol reduction may not be reached if plant stanol ester is not used according to recommendations. This review therefore concentrates on the optimal use of plant stanol ester as part of dietary management of hypercholesterolemia. For optimal cholesterol lowering aiming at a lower risk of cardiovascular disease, plant stanol ester should be used daily, in sufficient amounts, with a meal and in combination with other recommended dietary changes.

  14. Use of tobacco seed oil methyl ester in a turbocharged indirect injection diesel engine

    International Nuclear Information System (INIS)

    Usta, N.

    2005-01-01

    Vegetable oils and their methyl/ethyl esters are alternative renewable fuels for compression ignition engines. Different kinds of vegetable oils and their methyl/ethyl esters have been tested in diesel engines. However, tobacco seed oil and tobacco seed oil methyl ester have not been tested in diesel engines, yet. Tobacco seed oil is a non-edible vegetable oil and a by-product of tobacco leaves production. To the author's best knowledge, this is the first study on tobacco seed oil methyl ester as a fuel in diesel engines. In this study, potential tobacco seed production throughout the world, the oil extraction process from tobacco seed and the transesterification process for biodiesel production were examined. The produced tobacco seed oil methyl ester was characterized by exposing its major properties. The effects of tobacco seed oil methyl ester addition to diesel No. 2 on the performance and emissions of a four cycle, four cylinder turbocharged indirect injection (IDI) diesel engine were examined at both full and partial loads. Experimental results showed that tobacco seed oil methyl ester can be partially substituted for the diesel fuel at most operating conditions in terms of performance parameters and emissions without any engine modification and preheating of the blends. (Author)

  15. Influence of polyacrylic ester and silica fume on the mechanical properties of mortar for repair application

    Directory of Open Access Journals (Sweden)

    Chaohua Jiang

    2016-12-01

    Full Text Available Experimental investigations on the influence of different amounts of polyacrylic ester and silica fumes on the mechanical properties of mortar such as the compressive strength, splitting tensile strength, bonding strength, and abrasion resistance are presented in this article. The results show that the compressive and splitting tensile strength of mortar can be improved with the addition of polyacrylic ester and silica fumes. Results obtained from both the direct tensile bond test and flexural bond test indicate that the addition of polyacrylic ester and silica fumes improves the bond strength significantly, and the enhancement is more obvious with polyacrylic ester paste as interfacial adhesives. Furthermore, mortar incorporation of polyacrylic ester and silica fumes shows superior abrasion resistance compared to the control mortar. Therefore, the correct combination of polyacrylic ester and silica fumes to produce mortars has been shown to have synergistic effects, which results in excellent properties including high bond strength and superior abrasion resistance. Mortars containing polyacrylic ester and silica fumes are ideal for repairing concrete especially for hydraulic concrete structure.

  16. Exposure assessment of 3-monochloropropane-1, 2-diol esters from edible oils and fats in China.

    Science.gov (United States)

    Li, Chang; Nie, Shao-Ping; Zhou, Yong-Qiang; Xie, Ming-Yong

    2015-01-01

    3-monochoropropane-1, 2-diol (3-MCPD) esters from edible oils are considered to be a possible risk factor for adverse effects in human. In the present study, the exposure assessment of 3-MCPD esters to Chinese population was performed. A total of 143 edible oil and fat samples collected from Chinese markets were determined for the concentrations of 3-MCPD esters. The concentration data together with the data of fats consumed were analyzed by the point evaluation and probabilistic assessment for the exposure assessment. The point evaluation showed that the mean daily intake (DI) of 3-MCPD esters were lower than the value of provisional maximum tolerable daily intake (PMTDI) of 3-MCPD (2 µg/kg BW/d). The mean DI values in different age groups obtained from probabilistic assessment were similar to the results of the point evaluation. However, in high percentiles (95th, 97.5th, 99th), the DI values in all age groups were undesirably higher than the value of PMTDI. Overall, the children and adolescents exposed more to 3-MCPD esters than the adults. Uncertainty was also analyzed for the exposure assessment. Decreasing the level of 3-MCPD esters in edible oils and consuming less oil were top priority to minimize the risk of 3-MCPD esters. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Synthesis of TMP-ester biolubricant basestock from palm stearin fatty acids

    Science.gov (United States)

    Fadzel, Fatimatuzzahraa Mohd; Salimon, Jumat; Derawi, Darfizzi

    2018-04-01

    A potential biolubricant; TMP-ester was produced via esterification of fatty acids (FA) from palm stearin (PS) with trimethylolpropane (TMP). The synthesis was conducted at four conditions; temperature, time, molar ratio of FA:TMP and H2SO4 as catalyst (by percent based on the weight of FA and TMP) that are 150 °C, 2 hours, 4:1 and 1% of H2SO4 respectively. The composition of ester produced was determined using gas chromatography (GC-FID). The presence of ester group was confirmed by the means of FTIR by the existence of strong carboxyl band of ester, v(C=O) at 1746cm-1 and 1H and 13C NMR spectroscopy shows the chemical shift, δ of ester, C=O at 2.27-2.31 ppm and 173.45 ppm accordingly. From the esterification reaction, 95% product of TMP-ester was formed. The thermal and oxidative stability of TMP-ester is 200°C.

  18. Synthesis of novel naphthoquinone aliphatic amides and esters and their anticancer evaluation.

    Science.gov (United States)

    Kongkathip, Boonsong; Akkarasamiyo, Sunisa; Hasitapan, Komkrit; Sittikul, Pichamon; Boonyalai, Nonlawat; Kongkathip, Ngampong

    2013-02-01

    Fourteen new naphthoquinone aliphatic amides and seventeen naphthoquinone aliphatic esters were synthesized in nine to ten steps from 1-hydroxy-2-naphthoic acid with 9-25% overall yield for the amides, and 16-21% overall yield for the esters. The key step of the amide synthesis is a coupling reaction between amine and various aliphatic acids using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) as a coupling agent while for the ester synthesis, DCC/DMAP or CDI was used as the coupling reagent between aliphatic acids and naphthoquinone alcohol. Both naphthoquinone amides and esters were evaluated for their anticancer activity against KB cells. It was found that naphthoquinone aliphatic amides showed stronger anticancer activity than those of the esters when the chains are longer than 7-carbon atoms. The optimum chain of amides is expected to be 16-carbon atoms. In addition, naphthoquinone aliphatic esters with α-methyl on the ester moiety possessed much stronger anticancer activity than the straight chains. Decatenation assay revealed that naphthoquinone amide with 16-carbon atoms chain at 15 μM and 20 μM can completely inhibit hTopoIIα activity while at 10 μM the enzyme activity was moderately inhibited. Molecular docking result also showed the same trend as the cytotoxicity and decatenation assay. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  19. Investigations on the transport and metabolism of high density lipoprotein cholesteryl esters in African green monkeys

    International Nuclear Information System (INIS)

    Sorci-Thomas, M.G.

    1984-01-01

    The metabolic fate of circulating high density lipoprotein cholesteryl esters was studied in African green monkeys to determine the significance of the lipid transfer reaction on the catabolism of lipoprotein cholesteryl esters. A method of doubly labeling both moieties of lipoprotein cholesteryl esters with [ 3 He]cholesteryl oleate and cholesteryl [ 14 C]oleate was developed for the purpose of studying plasma cholesteryl ester metabolism in vivo. In these studies the total plasma [ 3 He]cholesterol turnover resulted in production rates, which ranged from 10-17 mg/kg day, similar to previously reported values in African green monkeys and in normal lipoproteinemic humans. In contrast to the production rates calculated from the decay of plasma 3 He-radioactivity, the production rates calculated from lipoproteins labeled with cholesteryl [ 14 C]oleate were approximately 2-3 times greater. In addition to these studies, a plasma cholesteryl ester transacylation activity was demonstrated in vitro when HDL containing doubly labeled cholesteryl esters were incubated with fresh plasma. These results demonstrated that high density lipoprotein cholesteryl esters undergo transacylation in vitro, resulting in release and reesterification of free [ 3 H]cholesterol

  20. Development of an analytical method for the simultaneous analysis of MCPD esters and glycidyl esters in oil-based foodstuffs.

    Science.gov (United States)

    Ermacora, Alessia; Hrnčiřík, Karel

    2014-01-01

    Substantial progress has been recently made in the development and optimisation of analytical methods for the quantification of 2-MCPD, 3-MCPD and glycidyl esters in oils and fats, and there are a few methods currently available that allow a reliable quantification of these contaminants in bulk oils and fats. On the other hand, no standard method for the analysis of foodstuffs has yet been established. The aim of this study was the development and validation of a new method for the simultaneous quantification of 2-MCPD, 3-MCPD and glycidyl esters in oil-based food products. The developed protocol includes a first step of liquid-liquid extraction and purification of the lipophilic substances of the sample, followed by the application of a previously developed procedure based on acid transesterification, for the indirect quantification of these contaminants in oils and fats. The method validation was carried out on food products (fat-based spreads, creams, margarine, mayonnaise) manufactured in-house, in order to control the manufacturing process and account for any food matrix-analyte interactions (the sample spiking was carried out on the single components used for the formulations rather than the final products). The method showed good accuracy (the recoveries ranged from 97% to 106% for bound 3-MCPD and 2-MCPD and from 88% to 115% for bound glycidol) and sensitivity (the LOD was 0.04 and 0.05 mg kg(-1) for bound MCPD and glycidol, respectively). Repeatability and reproducibility were satisfactory (RSD below 2% and 5%, respectively) for all analytes. The levels of salts and surface-active compounds in the formulation were found to have no impact on the accuracy and the other parameters of the method.

  1. 21 CFR 184.1009 - Adipic acid.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific....3 percent for meat products as defined in § 170.3(n)(29) of this chapter; 1.3 percent for snack...

  2. Enzymatic synthesis of arbutin undecylenic acid ester and its inhibitory effect on melanin synthesis.

    Science.gov (United States)

    Tokiwa, Yutaka; Kitagawa, Masaru; Raku, Takao; Yanagitani, Shusaku; Yoshino, Kenji

    2007-06-01

    Transesterification of arbutin and undecylenic acid vinyl ester was catalyzed by alkaline protease, Bioprase, in dimethylformamide to get arbutin derivative having undecylenic acid at 6-position of glucose moiety, 6-O-undecylenoyl p-hydroxyphenyl beta-D-glucopyranoside. The reaction rate increased with increase of arbutin concentration, and when its concentration was 0.9 M, the conversion rate was more than 90% under addition of 2 M undecylenic acid vinyl ester. The obtained arbutin ester significantly suppressed melanin production in murine B16 melanoma cells.

  3. Synthesis and cytotoxicity of boronated fatty esters for BNCT of cervix cancer

    International Nuclear Information System (INIS)

    Tambunchong, C.; Prachayasittikul, S.; Picha, P.; Tumpum, C.

    2000-01-01

    Esterification reactions of o-carboranic acid with six fatty alcohols, palmitoleyl, stearyl, oleyl, elaidyl, linoleyl and linoelaidyl alcohols, proceeded smoothly under nitrogen atmosphere with dimethylamino pyrimidine as a catalyst. The reaction gave the corresponding esters in moderate yields. Most of the synthetic esters are stable at room temperature except the linoleyl carboranate and linoelaidyl carboranate which decomposed within two weeks. The in vitro studies on Hela cells showed relatively low cytotoxic. The IC 50 of boronated esters were in range of 36-83 micrograms/cm 3 . (author)

  4. A new, direct analytical method using LC-MS/MS for fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD esters) in edible oils.

    Science.gov (United States)

    Yamazaki, K; Ogiso, M; Isagawa, S; Urushiyama, T; Ukena, T; Kibune, N

    2013-01-01

    A new, direct analytical method for the determination of 3-chloro-1,2-propanediol fatty acid esters (3-MCPD esters) was developed. The targeted 3-MCPD esters included five types of monoester and 25 [corrected] types of diester. Samples (oils and fats) were dissolved in a mixture of tert-butyl methyl ether and ethyl acetate (4:1), purified using two solid-phase extraction (SPE) cartridges (C(18) and silica), then analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Five monoesters and five diesters with the same fatty acid group could be separated and quantified. Pairs of 3-MCPD diesters carrying the same two different fatty acid groups, but at reversed positions (sn-1 and sn-2), could not be separated and so were expressed as a sum of both compounds. The limits of quantification (LOQs) were estimated to be between 0.02 to 0.08 mg kg(-1), depending on the types of 3-MCPD ester. Repeatability expressed as relative standard deviation (RSD(r)%) varied from 5.5% to 25.5%. The new method was shown to be applicable to various commercial edible oils and showed levels of 3-MCPD esters varying from 0.58 to 25.35 mg kg(-1). The levels of mono- and diesters ranged from 0.10 to 0.69 mg kg(-1) and from 0.06 to 16 mg kg(-1), respectively.

  5. Gamma-aminobutyric acid esters. 1. Synthesis, brain uptake, and pharmacological studies of aliphatic and steroid esters of gamma-aminobutyric acid

    International Nuclear Information System (INIS)

    Shashoua, V.E.; Jacob, J.N.; Ridge, R.; Campbell, A.; Baldessarini, R.J.

    1984-01-01

    Labeled and unlabeled aliphatic and steroid esters of gamma-amino[U- 14 C]butyric acid (GABA) were synthesized and tested for their capacity to penetrate the blood-brain barrier and for evidence of central neuropharmacological activity in rodents. The uptake of the labeled 9,12,15-octadecatrienyl (linolenyl), 3-cholesteryl, 1-butyl, and the 9-fluoro-11 beta,17-dihydroxy-16 alpha-methyl-3,20-dioxopregna -1,4-dien-21-yl (dexamethasone) esters of GABA into mouse brain increased 2-, 25-, 74-, and 81-fold over GABA, respectively. The cholesteryl ester of GABA depressed the general motor activity of mice and rats in a dose-dependent manner, whereas the 1-butyl, linolenyl, and dexamethasone esters were inactive by this test. Studies of the rates of hydrolysis, GABA receptor binding capacity, and octanol/water partition coefficients indicated that pharmacological activity of the esters after entry into the central nervous system (CNS) was dependent on their capacity to release GABA by enzymatic hydrolysis and their lipid solubility

  6. Fully convergent chemical synthesis of ester insulin: determination of the high resolution X-ray structure by racemic protein crystallography.

    Science.gov (United States)

    Avital-Shmilovici, Michal; Mandal, Kalyaneswar; Gates, Zachary P; Phillips, Nelson B; Weiss, Michael A; Kent, Stephen B H

    2013-02-27

    Efficient total synthesis of insulin is important to enable the application of medicinal chemistry to the optimization of the properties of this important protein molecule. Recently we described "ester insulin"--a novel form of insulin in which the function of the 35 residue C-peptide of proinsulin is replaced by a single covalent bond--as a key intermediate for the efficient total synthesis of insulin. Here we describe a fully convergent synthetic route to the ester insulin molecule from three unprotected peptide segments of approximately equal size. The synthetic ester insulin polypeptide chain folded much more rapidly than proinsulin, and at physiological pH. Both the D-protein and L-protein enantiomers of monomeric DKP ester insulin (i.e., [Asp(B10), Lys(B28), Pro(B29)]ester insulin) were prepared by total chemical synthesis. The atomic structure of the synthetic ester insulin molecule was determined by racemic protein X-ray crystallography to a resolution of 1.6 Å. Diffraction quality crystals were readily obtained from the racemic mixture of {D-DKP ester insulin + L-DKP ester insulin}, whereas crystals were not obtained from the L-ester insulin alone even after extensive trials. Both the D-protein and L-protein enantiomers of monomeric DKP ester insulin were assayed for receptor binding and in diabetic rats, before and after conversion by saponification to the corresponding DKP insulin enantiomers. L-DKP ester insulin bound weakly to the insulin receptor, while synthetic L-DKP insulin derived from the L-DKP ester insulin intermediate was fully active in binding to the insulin receptor. The D- and L-DKP ester insulins and D-DKP insulin were inactive in lowering blood glucose in diabetic rats, while synthetic L-DKP insulin was fully active in this biological assay. The structural basis of the lack of biological activity of ester insulin is discussed.

  7. Analysis of phosphate esters in plant material. Extraction and purification.

    Science.gov (United States)

    Isherwood, F A; Barrett, F C

    1967-09-01

    1. A critical study was made of the quantitative extraction of nucleotide and sugar phosphates from plant tissue by either boiling aqueous ethanol or cold trichloroacetic acid. The effect of the extraction technique on the inactivation of the enzymes in the plant tissue and the possibility of adsorption of the phosphate esters on the cell wall were especially considered. 2. In the recommended method the plant tissue was frozen in liquid nitrogen, ground to a powder and then blended with cold aqueous trichloroacetic acid containing 8-hydroxyquinoline to prevent adsorption. 3. The extract contained large amounts of trichloroacetic acid, cations, chloride, sugars, amino acids, hydroxy organic acids, phytic acid, orthophosphoric acid and high-molecular-weight material including some phosphorus-containing compounds. All of these were removed as they were liable to interfere with the chromatographic or enzymic assay of the individual nucleotide or sugar phosphates. 4. The procedure was as follows: the last traces of trichloroacetic acid were extracted with ether after the solution had been passed through a column of Dowex AG 50 in the hydrogen form to remove all cations. High-molecular-weight compounds were removed by ultrafiltration and low-molecular-weight solutes by a two-stage chromatography on cellulose columns with organic solvents. In the first stage, sugars, amino acids, chloride and phytic acid were separated by using a basic solvent (propan-1-ol-water-aqueous ammonia) and, in the second stage, the organic acids and orthophosphoric acid were separated by using an acidic solvent (di-isopropyl ether-formic acid-2-methylpropan-2-ol-water). The final solution of nucleotide and sugar phosphates was substantially free from other solutes and was suitable for the detection of individual phosphate esters by either chromatography or enzymic assay. 5. The recovery of d-glucose 6-phosphate or adenosine 5'-triphosphate added to a trichloroacetic acid extract simulating that

  8. Intratumor cholesteryl ester accumulation is associated with human breast cancer proliferation and aggressive potential: a molecular and clinicopathological study

    International Nuclear Information System (INIS)

    a Claret, 167 08025, Barcelona (Spain))" data-affiliation=" (Cardiovascular Research Center, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu i Sant Pau, Sant Antoni Ma Claret, 167 08025, Barcelona (Spain))" >Gonzalo-Calvo, David de; López-Vilaró, Laura; a Claret, 167 08025, Barcelona (Spain))" data-affiliation=" (Cardiovascular Research Center, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu i Sant Pau, Sant Antoni Ma Claret, 167 08025, Barcelona (Spain))" >Nasarre, Laura; Perez-Olabarria, Maitane; Vázquez, Tania; Escuin, Daniel; a Claret, 167 08025, Barcelona (Spain))" data-affiliation=" (Cardiovascular Research Center, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu i Sant Pau, Sant Antoni Ma Claret, 167 08025, Barcelona (Spain))" >Badimon, Lina; Barnadas, Agusti; Lerma, Enrique; a Claret, 167 08025, Barcelona (Spain))" data-affiliation=" (Cardiovascular Research Center, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu i Sant Pau, Sant Antoni Ma Claret, 167 08025, Barcelona (Spain))" >Llorente-Cortés, Vicenta

    2015-01-01

    The metabolic effect of intratumor cholesteryl ester (CE) in breast cancer remains poorly understood. The objective was to analyze the relationship between intratumor CE content and clinicopathological variables in human breast carcinomas. We classified 30 breast carcinoma samples into three subgroups: 10 luminal-A tumors (ER+/PR+/Her2-), 10 Her-2 tumors (ER-/PR-/Her2+), and 10 triple negative (TN) tumors (ER-/PR-/Her2-). We analyzed intratumor neutral CE, free cholesterol (FC) and triglyceride (TG) content by thin layer chromatography after lipid extraction. RNA and protein levels of lipid metabolism and invasion mediators were analyzed by real time PCR and Western blot analysis. Group-wise comparisons, linear regression and logistic regression models showed a close association between CE-rich tumors and higher histologic grade, Ki-67 and tumor necrosis. CE-rich tumors displayed higher mRNA and protein levels of low-density lipoprotein receptor (LDLR) and scavenger receptor class B member 1 (SCARB1). An increased expression of acetyl-Coenzyme A acetyltransferase 1 (ACAT1) in CE-rich tumors was also reported. Intratumor CE accumulation is intimately linked to proliferation and aggressive potential of breast cancer tumors. Our data support the link between intratumor CE content and poor clinical outcome and open the door to new antitumor interventions. The online version of this article (doi:10.1186/s12885-015-1469-5) contains supplementary material, which is available to authorized users

  9. Cholesteryl ester transfer protein alters liver and plasma triglyceride metabolism through two liver networks in female mice[S

    Science.gov (United States)

    Palmisano, Brian T.; Le, Thao D.; Zhu, Lin; Lee, Yoon Kwang; Stafford, John M.

    2016-01-01

    Elevated plasma TGs increase risk of cardiovascular disease in women. Estrogen treatment raises plasma TGs in women, but molecular mechanisms remain poorly understood. Here we explore the role of cholesteryl ester transfer protein (CETP) in the regulation of TG metabolism in female mice, which naturally lack CETP. In transgenic CETP females, acute estrogen treatment raised plasma TGs 50%, increased TG production, and increased expression of genes involved in VLDL synthesis, but not in nontransgenic littermate females. In CETP females, estrogen enhanced expression of small heterodimer partner (SHP), a nuclear receptor regulating VLDL production. Deletion of liver SHP prevented increases in TG production and expression of genes involved in VLDL synthesis in CETP mice with estrogen treatment. We also examined whether CETP expression had effects on TG metabolism independent of estrogen treatment. CETP increased liver β-oxidation and reduced liver TG content by 60%. Liver estrogen receptor α (ERα) was required for CETP expression to enhance β-oxidation and reduce liver TG content. Thus, CETP alters at least two networks governing TG metabolism, one involving SHP to increase VLDL-TG production in response to estrogen, and another involving ERα to enhance β-oxidation and lower liver TG content. These findings demonstrate a novel role for CETP in estrogen-mediated increases in TG production and a broader role for CETP in TG metabolism. PMID:27354419

  10. Cholesteryl ester transfer protein alters liver and plasma triglyceride metabolism through two liver networks in female mice.

    Science.gov (United States)

    Palmisano, Brian T; Le, Thao D; Zhu, Lin; Lee, Yoon Kwang; Stafford, John M

    2016-08-01

    Elevated plasma TGs increase risk of cardiovascular disease in women. Estrogen treatment raises plasma TGs in women, but molecular mechanisms remain poorly understood. Here we explore the role of cholesteryl ester transfer protein (CETP) in the regulation of TG metabolism in female mice, which naturally lack CETP. In transgenic CETP females, acute estrogen treatment raised plasma TGs 50%, increased TG production, and increased expression of genes involved in VLDL synthesis, but not in nontransgenic littermate females. In CETP females, estrogen enhanced expression of small heterodimer partner (SHP), a nuclear receptor regulating VLDL production. Deletion of liver SHP prevented increases in TG production and expression of genes involved in VLDL synthesis in CETP mice with estrogen treatment. We also examined whether CETP expression had effects on TG metabolism independent of estrogen treatment. CETP increased liver β-oxidation and reduced liver TG content by 60%. Liver estrogen receptor α (ERα) was required for CETP expression to enhance β-oxidation and reduce liver TG content. Thus, CETP alters at least two networks governing TG metabolism, one involving SHP to increase VLDL-TG production in response to estrogen, and another involving ERα to enhance β-oxidation and lower liver TG content. These findings demonstrate a novel role for CETP in estrogen-mediated increases in TG production and a broader role for CETP in TG metabolism. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.

  11. Treatment of timber products with gaseous borate esters, Part 1: factors influencing the treatment process

    CSIR Research Space (South Africa)

    Turner, P

    1995-08-01

    Full Text Available Several factors which influence the treatment of timber products with vapour phase preservatives such as borate esters are considered. Gas flow rate through the substrate was found to be a significant factor limiting both preservative penetration...

  12. The majority of vitamin A is transported as retinyl esters in the blood of most carnivores.

    Science.gov (United States)

    Schweigert, F J; Ryder, O A; Rambeck, W A; Zucker, H

    1990-01-01

    1. In canines and mustelides total vitamin A was 10-50 times higher compared to other species due to a high amount of retinyl esters (40-99% of total vitamin A) in blood plasma. The dominant vitamin A ester was in most species retinyl stearate. 2. In Ursidae, Procyonidae, Viveridae and Felidae, total vitamin A was much lower. When present, however, retinyl esters also represented 10-65% of total vitamin A in plasma. 3. Only retinol was detected in plasma of the family, Hyaenidae, and the suborder, Pinnipedia. 4. In maned wolf cubs it was found that retinol, retinyl esters and alpha-tocopherol increased with the age of the animals, reaching values comparable to adult animals at the age of 5 months.

  13. Biodegradable Poly (Ester Urethane) Urea Biomaterials For Applications in Combat Casualty Care

    National Research Council Canada - National Science Library

    Guelcher, S. A; Sriniwasan, A; Hollinger, J. O

    2006-01-01

    A family of biocompatible, biodegradable poly(ester urethane)urea (PEUUR) biomaterials has been developed that degrade to non-toxic by-products and support the attachment and proliferation of cells...

  14. Decreased plasma cholesterol esterification and cholesteryl ester transfer in hypopituitary patients on glucocorticoid replacement therapy

    NARCIS (Netherlands)

    Beentjes, JAM; Van Tol, A; Sluiter, WJ; Dullaart, RPF

    Cardiovascular risk is increased in hypopituitary patients. No data are available with respect to the effect of glucocorticoid replacement therapy on high density lipoproteins (HDL) metabolism in such patients. Plasma lecithin:choresterol acyl transferase (LCAT), cholesteryl ester transfer protein

  15. Determination of the absolute configuration of (+) - surinamensin's via diastereomeric O-methylmandelic esters

    International Nuclear Information System (INIS)

    Santos, L. da S.; Barata, L.E.S.

    1990-01-01

    The absolute configurarion of (+) surinamensin, a 8.0.4' neolignan, has been determined based on its O-methymandalates esters. Nuclear magnetic resonance and infrared and mass spectroscopy analysis are presented. (C.G.C.) [pt

  16. Building ultramicropores within organic polymers based on a thermosetting cyanate ester resin.

    Science.gov (United States)

    Zhang, Bufeng; Wang, Zhonggang

    2009-09-07

    Ultramicropores with high surface areas (>530 m(2) g(-1)) and narrow micropore size distribution (4-6 A) were engineered within a new cyanate ester resin, extending the microporous concept (thermosetting resins in the area of polymer chemistry.

  17. Liquid chromatographic analysis of a formulated ester from a gas-turbine engine test

    Science.gov (United States)

    Jones, W. R., Jr.; Morales, W.

    1983-01-01

    Size exclusion chromatography (SEC) utilizing mu-Bondagel and mu-Styragel columns with a tetrahydrofuran mobile phase was used to determine the chemical degradation of lubricant samples from a gas-turbine engine test. A MIL-L-27502 candidate, ester-based lubricant was run in a J57-29 engine at a bulk oil temperature of 216 C. In general, the analyses indicated a progressive loss of primary ester, additive depletion, and formation of higher molecular weight material. An oil sample taken at the conclusion of the test showed a reversal of this trend because of large additions of new oil. The high-molecular-weight product from the degraded ester absorbed strongly in the ultraviolet region at 254 nanometers. This would indicate the presence of chromophoric groups. An analysis of a similar ester lubricant from a separate high-temperature bearing test yielded qualitatively similar results.

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

    Energy Technology Data Exchange (ETDEWEB)

    Altiparmak, D.; Keskin, A.; Koca, A. [Gazi University, Ankara (Turkey). Technical Education Faculty; Guru, M. [Gazi University, Ankara (Turkey). Engineering and Architectural Faculty

    2007-01-15

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

  19. Optimisation of stabilised carboxylesterase NP for enantioselective hydrolysis of naproxen methyl ester

    CSIR Research Space (South Africa)

    Steenkamp, Lucia H

    2008-12-01

    Full Text Available Although the enantioselective kinetic resolution of ester racemates of the non-steroidal antiinflammatory drug naproxen ([2-(6-methoxy-2-naphthyl) propionic acid]) is a common demonstration for biocatalysis, the enantiomeric excess of the reactions...

  20. Unsaturated Fatty Acid Esters Metathesis Catalyzed by Silica Supported WMe5

    KAUST Repository

    Riache, Nassima

    2015-11-14

    Metathesis of unsaturated fatty acid esters (FAEs) by silica supported multifunctional W-based catalyst is disclosed. This transformation represents a novel route towards unsaturated di-esters. Especially, the self-metathesis of ethyl undecylenate results almost exclusively on the homo-coupling product whereas with such catalyst, 1-decene gives ISOMET (isomerization and metathesis olefin) products. The olefin metathesis in the presence of esters is very selective without any secondary cross-metathesis products demonstrating that a high selective olefin metathesis could operate at 150 °C. Additionally, a cross-metathesis of unsaturated FAEs and α-olefins allowed the synthesis of the corresponding ester with longer hydrocarbon skeleton without isomerisation.

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

    Science.gov (United States)

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

    2007-01-01

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

  2. Shank otsustab lahkumise pärast puhkuselt naasmist / Ester Shank

    Index Scriptorium Estoniae

    Šank, Ester, 1956-

    2002-01-01

    Välismaal oma korralist suvepuhkust veetev presidendi pressinõunik Ester Shank ei kinnita riigiametnike ringkondades levivaid kuuldusi, mille kohaselt on ta juba langetanud otsuse Kadrioru lossist lahkuda

  3. Nooruslikud juubilarid: fotokelder Lee 20 ja fotomuuseum 30 / Mall Parmas, Betty Ester-Väljaots

    Index Scriptorium Estoniae

    Parmas, Mall

    2013-01-01

    Peeter Toominga algatusel 1992. aastal asutatud Lee fotokeldrist. Loetletud fotomuuseumis oma töid eksponeerinud fotograafid. Ülevaatenäitus "Lee fotokelder 20" 17. jaanuarist 20. märtsini, koostaja Betty Ester-Väljaots

  4. Improvement of Fructanohydrolase Production in Aspergillus niger SL-09 by Sucrose Ester

    Directory of Open Access Journals (Sweden)

    Xiang-Yang Ge

    2006-01-01

    Full Text Available The influence of carbon sources, nitrogen sources, and the addition of sucrose ester on fructanohydrolase production was investigated. The enzyme production varied depending on the carbon source. Apart from that, it was found that the enzyme activities formed by Aspergillus niger SL-09 were enhanced dramatically by the addition of sucrose ester S-770 to the medium. The effect of sucrose ester on enzyme production was also studied on molecular level, and it was confirmed that the transcription was activated by the addition of sucrose ester to the medium. The response surface methodology (RSM was used to optimize the composition for the production of fructanohydrolase, and the enzyme activities were enhanced more than 7-fold than those obtained in the basal medium.

  5. Binding of indomethacin methyl ester to cyclooxygenase-2. A computational study.

    Science.gov (United States)

    Sárosi, Menyhárt-Botond

    2018-06-05

    Inhibitors selective towards the second isoform of prostaglandin synthase (cyclooxygenase, COX-2) are promising nonsteroidal anti-inflammatory drugs and antitumor medications. Methylation of the carboxylate group in the relatively nonselective COX inhibitor indomethacin confers significant COX-2 selectivity. Several other modifications converting indomethacin into a COX-2 selective inhibitor have been reported. Earlier experimental and computational studies on neutral indomethacin derivatives suggest that the methyl ester derivative likely binds to COX-2 with a similar binding mode as that observed for the parent indomethacin. However, docking studies followed by molecular dynamics simulations revealed two possible binding modes in COX-2 for indomethacin methyl ester, which differs from the experimental binding mode found for indomethacin. Both alternative binding modes might explain the observed COX-2 selectivity of indomethacin methyl ester. Graphical abstract Binding of indomethacin methyl ester to cyclooxygenase-2.

  6. N-Acetyl-D- and L-esters of 5'-AMP hydrolyze at different rates

    Science.gov (United States)

    Wickramasinghe, N. S.; Lacey, J. C. Jr; Lacey JC, J. r. (Principal Investigator)

    1993-01-01

    Studies of the properties of aminoacyl derivatives of 5'-AMP are aimed at understanding the origin of the process of protein synthesis. Aminoacyl (2',3') esters of 5'-AMP can serve as models of the 3'-terminus of aminoacyl tRNA. We report here on the relative rates of hydrolysis of Ac-D- and L-Phe AMP esters as a function of pH. At all pHs above 3, the rate constant of hydrolysis of the Ac-L-Phe ester is 1.7 to 2.1 times that of Ac-D-Phe ester. The D-isomer seems partially protected from hydrolysis by a stronger association with the adenine ring of the 5'-AMP.

  7. Steryl ester synthesis, storage and hydrolysis: A contribution to sterol homeostasis.

    Science.gov (United States)

    Korber, Martina; Klein, Isabella; Daum, Günther

    2017-12-01

    Sterols are essential lipids of all eukaryotic cells, appearing either as free sterols or steryl esters. Besides other regulatory mechanisms, esterification of sterols and hydrolysis of steryl esters serve to buffer both an excess and a lack of free sterols. In this review, the esterification process, the storage of steryl esters and their mobilization will be described. Several model organisms are discussed but the focus was set on mammals and the yeast Saccharomyces cerevisiae. The contribution of imbalanced cholesterol homeostasis to several human diseases, namely Wolman disease, cholesteryl ester storage disease, atherosclerosis and Alzheimer's disease, Niemann-Pick type C and Tangier disease is described. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. One-pot synthesis of thermoplastic mixed paramylon esters using trifluoroacetic anhydride.

    Science.gov (United States)

    Shibakami, Motonari; Tsubouchi, Gen; Sohma, Mitsugu; Hayashi, Masahiro

    2015-03-30

    Mixed paramylon esters prepared from paramylon (a storage polysaccharide of Euglena), acetic acid, and a long-chain fatty acid by one-pot synthesis using trifluoroacetic anhydride as a promoter and solvent were shown to have thermoplasticity. Size exclusion chromatography indicated that the mixed paramylon esters had a weight average molecular weight of approximately 4.9-6.7×10(5). Thermal analysis showed that these esters were stable in terms of the glass transition temperature (>90°C) and 5% weight loss temperature (>320°C). The degree of substitution of the long alkyl chain group, a dominant factor determining thermoplasticity, was controlled by tuning the feed molar ratio of acetic acid and long-chain fatty acid to paramylon. These results implied that the one-pot synthesis is useful for preparing structurally-well defined thermoplastic mixed paramylon esters with high molecular weight. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Ester Tuiksoo : Saksamaa on Eestile biomassi ja GMO vallas eeskujuks / Ain Lember

    Index Scriptorium Estoniae

    Lember, Ain

    2006-01-01

    Põllumajandusminister Ester Tuiksoo ja abiminister Rain Vändre kohtusid Kielis Schleswig-Holsteini liidumaa ministri dr. Christian von Boetticheriga, peateemadeks abi biomassi ja geneetiliselt muundatud kultuurtaimede kooseksisteerimise vallas

  10. Influence of Fatty Acid Methyl Esters on Fuel properties of Biodiesel ...

    African Journals Online (AJOL)

    Influence of Fatty Acid Methyl Esters on Fuel properties of Biodiesel Produced from the. Seeds Oil of Curcubita ... Gas chromatograph coupled with mass spectrophotometer (GC-MS). The results indicate ..... Chemical and physical properties of ...

  11. Occurrence of 3-MCPD and glycidyl esters in edible oils in the United States.

    Science.gov (United States)

    MacMahon, Shaun; Begley, Timothy H; Diachenko, Gregory W

    2013-01-01

    Fatty acid esters of 3-monochloropropanediol (3-MCPD) and glycidol are processing contaminants found in a wide range of edible oils. While both 3 MCPD and glycidol have toxicological properties that at present has concerns for food safety, the published occurrence data are limited. Occurrence information is presented for the concentrations of 3-MCPD and glycidyl esters in 116 retail and/or industrial edible oils and fats using LC-MS/MS analysis of intact esters. The concentrations for bound 3-MCPD ranged from below the limit of quantitation (3-MCPD and glycidol were seen in refined palm oil and palm olein samples. Palm olein samples also contained a higher percentage of 3-MCPD in mono-ester form than any other type of oil.

  12. Phthalate Esters and Reproductive Toxicity** Presentation requested by State of Mass Use Reductions Committee-TURI

    Science.gov (United States)

    Phthalate esters and reproductive toxicity the presentation described the uses of phthalates, the toxicity to mammals with a focus on reproductive toxicity and the potency of these chemicals to disrupt mammalian reproductive development in utero

  13. Nickel-Catalyzed C–O Bond-Cleaving Alkylation of Esters: Direct Replacement of the Ester Moiety by Functionalized Alkyl Chains

    KAUST Repository

    Liu, Xiangqian; Jia, Jiaqi; Rueping, Magnus

    2017-01-01

    Two efficient protocols for the nickel-catalyzed aryl–alkyl cross-coupling reactions using esters as coupling components have been established. The methods enable the selective oxidative addition of nickel to acyl C–O and aryl C–O bonds and allow the aryl–alkyl cross-coupling via decarbonylative bond cleavage or through cleavage of a C–O bond with high efficiency and good functional group compatibility. The protocols allow the streamlined, unconventional utilization of widespread ester groups and their precursors, carboxylic acids and phenols, in synthetic organic chemistry.

  14. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction.

    Science.gov (United States)

    Xiong, Yiwen; Mei, Haibo; Wu, Lingmin; Han, Jianlin; Pan, Yi; Li, Guigen

    2014-01-01

    A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88-98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easily cleaved under acidic conditions.

  15. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction

    Directory of Open Access Journals (Sweden)

    Yiwen Xiong

    2014-03-01

    Full Text Available A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88–98% as well as high diastereoselectivities (96:4 to 99:1. Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easily cleaved under acidic conditions.

  16. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction

    OpenAIRE

    Xiong, Yiwen; Mei, Haibo; Wu, Lingmin; Han, Jianlin; Pan, Yi; Li, Guigen

    2014-01-01

    A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88–98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be ea...

  17. Nickel-Catalyzed C–O Bond-Cleaving Alkylation of Esters: Direct Replacement of the Ester Moiety by Functionalized Alkyl Chains

    KAUST Repository

    Liu, Xiangqian

    2017-06-07

    Two efficient protocols for the nickel-catalyzed aryl–alkyl cross-coupling reactions using esters as coupling components have been established. The methods enable the selective oxidative addition of nickel to acyl C–O and aryl C–O bonds and allow the aryl–alkyl cross-coupling via decarbonylative bond cleavage or through cleavage of a C–O bond with high efficiency and good functional group compatibility. The protocols allow the streamlined, unconventional utilization of widespread ester groups and their precursors, carboxylic acids and phenols, in synthetic organic chemistry.

  18. Structure and reactivity of boron-ate complexes derived from primary and secondary boronic esters.

    Science.gov (United States)

    Feeney, Kathryn; Berionni, Guillaume; Mayr, Herbert; Aggarwal, Varinder K

    2015-06-05

    Boron-ate complexes derived from primary and secondary boronic esters and aryllithiums have been isolated, and the kinetics of their reactions with carbenium ions studied. The second-order rate constants have been used to derive nucleophilicity parameters for the boron-ate complexes, revealing that nucleophilicity increased with (i) electron-donating aromatics on boron, (ii) neopentyl glycol over pinacol boronic esters, and (iii) 12-crown-4 ether.

  19. Ophthalmic ester removal in the agar state giant molecule; Kantenjo kobunshi de futarusan esuteru jokyo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    Matsubara professors of Tokyo College of Pharmacy developed the technique which simply removed phthalic ester from the solution. The property in which the giant molecule called the poly N isopropyl acrylamide cohered like the agar, when 32 degrees C is exceeded, was utilized, and the phthalic ester of poor solubility is taken in the flocculation stage. It is expected with that it can be utilized for wastewater treatment and solicitation quantity thing analysis in the environment. (translated by NEDO)

  20. Transesterification of Vegetable Oils with Ethanol and Characterization of the Key Fuel Properties of Ethyl Esters

    Directory of Open Access Journals (Sweden)

    Stamoulis Stournas

    2009-06-01

    Full Text Available The transesterification reactions of four different vegetable oils (sunflower, rapeseed, olive oil and used frying oil with ethanol, using sodium hydroxide as catalyst, were studied. The ester preparation involved a two-step transesterification reaction, followed by purification. The effects of the mass ratio of catalyst to oil (0.25 – 1.5%, the molar ratio of ethanol to oil (6:1 – 12:1, and the reaction temperature (35 – 90 °C were studied for the conversion of sunflower oil to optimize the reaction conditions in both stages. The rest of the vegetable oils were converted to ethyl esters under optimum reaction parameters. The optimal conditions for first stage transesterification were an ethanol/oil molar ratio of 12:1, NaOH amount (1% wt/wt, and 80 °C temperature, whereas the maximum yield of ethyl esters reached 81.4% wt/wt. In the second stage, the yield of ethyl esters was improved by 16% in relation with the one-stage transesterification, which was obtained under the following optimal conditions: catalyst concentration 0.75% and ethanol/oil molar ratio 6:1. The fuel properties of the esters were measured according to EN test methods. Based on the experimental results one can see that the ethyl esters do not differ significantly from methyl esters. Moreover, the results showed that the values of density, viscosity, and higher heating value of ethyl esters were similar to those of automotive and heavy duty engine diesel fuel. However, the CFPP values were higher, which may contribute to potential difficulties in cold starts. On the other hand, the flash points, which were higher than those of diesel fuel constituted a safety guarantee from the point of view of handling and storage.