WorldWideScience

Sample records for aqueous oleic acid

  1. Growth and shape transformations of giant phospholipid vesicles upon interaction with an aqueous oleic acid suspension

    CERN Document Server

    Peterlin, Primoz; Kogej, Ksenija; Svetina, Sasa; Walde, Peter

    2009-01-01

    The interaction of two types of vesicle systems was investigated: micrometer-sized, giant unilamellar vesicles (GUVs) formed from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and submicrometer-sized, large unilamellar vesicles (LUVs) formed from oleic acid and oleate, both in a buffered aqueous solution (pH=8.8). Individual POPC GUVs were transferred with a micropipette into a suspension of oleic acid/oleate LUVs, and the shape changes of the GUVs were monitored using optical microscopy. The behavior of POPC GUVs upon transfer into a 0.8 mM suspension of oleic acid, in which oleic acid/oleate forms vesicular bilayer structures, was qualitatively different from the behavior upon transfer into a 0.3 mM suspension of oleic acid/oleate, in which oleic acid/oleate is predominantly present in the form of monomers and possibly non-vesicular aggregates. In both cases, changes in vesicle morphology were observed within tens of seconds after the transfer. Vesicle initially started to evaginate. In 60% of the...

  2. Aqueous Dispersions of Silica Stabilized with Oleic Acid Obtained by Green Chemistry

    Directory of Open Access Journals (Sweden)

    Cristina Lavinia Nistor

    2016-01-01

    Full Text Available The present study describes for the first time the synthesis of silica nanoparticles starting from sodium silicate and oleic acid (OLA. The interactions between OLA and sodium silicate require an optimal OLA/OLANa molar ratio able to generate vesicles that can stabilize silica particles obtained by the sol-gel process of sodium silicate. The optimal molar ratio of OLA/OLANa can be ensured by a proper selection of OLA and respectively of sodium silicate concentration. The titration of sodium silicate with OLA revealed a stabilization phenomenon of silica/OLA vesicles and the dependence between their average size and reagent’s molar ratio. Dynamic light scattering (DLS and scanning electron microscopy (SEM measurements emphasized the successful synthesis of silica nanoparticles starting from renewable materials, in mild condition of green chemistry. By grafting octadecyltrimethoxysilane on the initial silica particles, an increased interaction between silica particles and the OLA/OLANa complex was achieved. This interaction between the oleyl and octadecyl chains resulted in the formation of stable gel-like aqueous systems. Subsequently, olive oil and an oleophylic red dye were solubilized in these stable aqueous systems. This great dispersing capacity of oleosoluble compounds opens new perspectives for future green chemistry applications. After the removal of water and of the organic chains by thermal treatment, mesoporous silica was obtained.

  3. Oleic acid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    The biosynthesis of fatty acids in cyanobacteria is very similar to the well characterized system found in green plants. However, the initial desaturation of stearic acid in cyanobacteria appears to represent a significant departure from plant systems in which stearoyl-ACP is the exclusive substrate for desaturation. In Anabaena variabilis, the substrate appears to be monoglucosyldiacylglycerol, a lipid not found in plants. The authors examined five different cyanobacteria to determine if the pathway in A. variabilis was generally present in other cyanobacteria. The cyanobacteria studied were A. variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis marina, and Anacystis nidulans. Each were grown in liquid culture, harvested, and examined for stearoyl-ACP desaturase activity or incubated with 14CO2. None of the cyanobacteria contained any stearoyl-ACP desaturase activity in whole homogenates or 105,000g supernatants. All were capable of incorporating 14CO2 into monoglucosyldiacylglycerol and results from incubations of 20 min, 1 hr, 1 hr + 10 hr chase were consistent with monoglucosyldiacylglycerol serving as precursor for monogalctosyldiacylglycerol. Thus, initial evidence is consistent with oleic acid biosynthesis occurring by desaturation of stearoyl-monoglucosyldiacylglycerol in all cyanobacteria

  4. Adsorption of oleic acid at sillimanite/water interface.

    Science.gov (United States)

    Kumar, T V Vijaya; Prabhakar, S; Raju, G Bhaskar

    2002-03-15

    The interaction of oleic acid at sillimanite-water interface was studied by adsorption, FT-IR, and zeta potential measurements. The isoelectric point (IEP) of sillimanite obtained at pH 8.0 was found to shift in the presence of oleic acid. This shift in IEP was attributed to chemisorption of oleic acid on sillimanite. Adsorption experiments were conducted at pH 8.0, where the sillimanite surface is neutral. The adsorption isotherm exhibited a plateau around 5 micromol/m2 that correspond to a monolayer formation. Adsorption of oleic acid on sillimanite, alumina, and aluminum hydroxide was studied by FT-IR. Chemisorption of oleic acid on the above substrates was confirmed by FT-IR studies. Hydroxylation of mineral surface was found to be essential for the adsorption of oleic acid molecules. These surface hydroxyl sites were observed to facilitate deprotonation of oleic acid and its subsequent adsorption. Thus protons from oleic acid react with surface hydroxyl groups and form water molecules. Based on the experimental results, the mechanism of oleic acid adsorption on mineral substrate was proposed. Free energy of adsorption was estimated using the Stern-Graham equation for a sillimanite-oleate system. PMID:16290466

  5. Oleic Acid: Natural variation and potential enhancement in oilseed crops.

    Science.gov (United States)

    Oleic acid is a monounsaturated omega 9 fatty acid (MUFA, C18:1) which can be found in various plant lipids and animal fats. Unlike omega 3 (a-linolenic acid, C18:3) and omega 6 (linoleic acid, C18:2) fatty acids which are essential because they cannot be synthesized by humans and must be obtained f...

  6. Capillary electrophoresis of some free fatty acids using partially aqueous electrolyte systems and indirect UV detection. Application to the analysis of oleic and linoleic acids in peanut breeding lines

    Science.gov (United States)

    This study has shown for the first time the suitability of CE with a partially aqueous electrolyte system for the analysis of free fatty acids (FFA's) in small portions of single peanut seeds. The partially aqueous electrolyte system consisted of 40 mM Tris, 2.5 mM adenosine-5'-monophosphate (AMP) ...

  7. Oleic acid-embedded nanoliposome as a selective tumoricidal agent.

    Science.gov (United States)

    Jung, Sujin; Lee, Sangah; Lee, Hyejin; Yoon, Jaejin; Lee, E K

    2016-10-01

    HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cell), a molecular complex of human α-lactalbumin and oleic acid, is known to have selective cytotoxic activity against certain types of tumors. This cytotoxicity is known to stem from water-insoluble oleic acid. In this study, we manufactured an alternative complex using liposome as an oleic acid delivery vesicle. We named this nanolipoplex LIMLET (LIposome Made LEthal to Tumor cell). The LIMLET vesicle contained approximately 90,200 oleic acid molecules inserted into its lipophilic phospholipid bilayer and had a nominal mean diameter of 127nm. Using a WST-1 assay, its cytotoxicity against two cancer cell lines, MDA-MB-231 (human breast cancer) and A549 (human lung cancer), were tested. The results were compared with that of a normal cell line, Vero (from monkey kidney). We found that (1) LIMLET showed distinctive cytotoxicity against A549 and MDA-MB-231 cells, whereas bare liposomes (containing no oleic acid) had no toxicity, even at high concentrations, and (2) LIMLET demonstrated selective, concentration-dependent toxicity against the cancer cells: the LD50 values of MDA-MB-231 and A549 cells were 1.3 and 2.2nM LIMLET, respectively, whereas the LD50 of Vero was 5.7nM. The strength of the tumoricidal effect appeared to stem from the number of oleic acid molecules present. Our result suggests that LIMLET, like HAMLET, is an interesting nanolipoplex that can potentially be developed into tumor treatments.

  8. Oleic acid-embedded nanoliposome as a selective tumoricidal agent.

    Science.gov (United States)

    Jung, Sujin; Lee, Sangah; Lee, Hyejin; Yoon, Jaejin; Lee, E K

    2016-10-01

    HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cell), a molecular complex of human α-lactalbumin and oleic acid, is known to have selective cytotoxic activity against certain types of tumors. This cytotoxicity is known to stem from water-insoluble oleic acid. In this study, we manufactured an alternative complex using liposome as an oleic acid delivery vesicle. We named this nanolipoplex LIMLET (LIposome Made LEthal to Tumor cell). The LIMLET vesicle contained approximately 90,200 oleic acid molecules inserted into its lipophilic phospholipid bilayer and had a nominal mean diameter of 127nm. Using a WST-1 assay, its cytotoxicity against two cancer cell lines, MDA-MB-231 (human breast cancer) and A549 (human lung cancer), were tested. The results were compared with that of a normal cell line, Vero (from monkey kidney). We found that (1) LIMLET showed distinctive cytotoxicity against A549 and MDA-MB-231 cells, whereas bare liposomes (containing no oleic acid) had no toxicity, even at high concentrations, and (2) LIMLET demonstrated selective, concentration-dependent toxicity against the cancer cells: the LD50 values of MDA-MB-231 and A549 cells were 1.3 and 2.2nM LIMLET, respectively, whereas the LD50 of Vero was 5.7nM. The strength of the tumoricidal effect appeared to stem from the number of oleic acid molecules present. Our result suggests that LIMLET, like HAMLET, is an interesting nanolipoplex that can potentially be developed into tumor treatments. PMID:27424089

  9. α-Lactalbumin:Oleic Acid Complex Spontaneously Delivers Oleic Acid to Artificial and Erythrocyte Membranes.

    Science.gov (United States)

    Wen, Hanzhen; Strømland, Øyvind; Halskau, Øyvind

    2015-09-25

    Human α-lactalbumin made lethal to tumor cells (HAMLET) is a tumoricidal complex consisting of human α-lactalbumin and multiple oleic acids (OAs). OA has been shown to play a key role in the activity of HAMLET and its related complexes, generally known as protein-fatty acid (PFA) complexes. In contrast to what is known about the fate of the protein component of such complexes, information about what happens to OA during their action is still lacking. We monitored the membrane, OA and protein components of bovine α-lactalbumin complexed with OA (BLAOA; a HAMLET-like substance) and how they associate with each other. Using ultracentrifugation, we found that the OA and lipid components follow each other closely. We then firmly identify a transfer of OA from BLAOA to both artificial and erythrocyte membranes, indicating that natural cells respond similarly to BLAOA treatment as artificial membranes. Uncomplexed OA is unable to similarly affect membranes at the conditions tested, even at elevated concentrations. Thus, BLAOA can spontaneously transfer OA to a lipid membrane. After the interaction with the membrane, the protein is likely to have lost most or all of its OA. We suggest a mechanism for passive import of mainly uncomplexed protein into cells, using existing models for OA's effect on membranes. Our results are consistent with a membrane destabilization mediated predominantly by OA insertion being a significant contribution to PFA cytotoxicity. PMID:26297199

  10. 78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

    Science.gov (United States)

    2013-04-03

    ... AGENCY 40 CFR Part 180 Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic...: This regulation establishes an exemption from the requirement of a tolerance for residues of castor oil... residues of castor oil, polymer with adipic acid, linoleic acid, oleic acid and ricinoleic acid on food...

  11. Effects of oleic acid on pulmonary capillary leak and thromboxanes

    International Nuclear Information System (INIS)

    The role of arachidonic acid metabolites in oleic acid-induced lung injury in anesthetized dogs was investigated. Oleic acid was administered as a bolus injection into the pulmonary artery after either indomethacin (10 mg/kg iv) or vehicle. Measurements of hemodynamic parameters, mean systemic (MAP), pulmonary capillary wedge, and pulmonary artery pressures (PAP), cardiac output, arterial blood gases, extravascular lung waters (EVLW) by thermaldye double indicator dilution techniques and plasma immunoreactive thromboxane B2 (iTxB2), by radioimmunoassay were obtained at zero time (baseline) and 20 min following each oleic acid injection. A new noninvasive technique was employed to measure pulmonary capillary protein leak by the scintigraphic analysis of intravenously administered technetium-99m radiolabeled human serum albumin (99mTc -HSA) in the cardiac and lung regions. Oleic acid injection caused a significant dose related fall in MAP, arterial pO2, and cardiac output, and increases in EVLW and plasma iTxB2 in the vehicle pretreated animals, while mean PAP remained unchanged. In contrast, in the indomethacin pretreated dogs, MAP, EVLW, cardiac output, and plasma iTxB2 levels did not change from baseline values and there was an increase in mean PAP. Pulmonary vascular resistance was significantly elevated in both groups

  12. Facile method to synthesize oleic acid-capped magnetite nanoparticles

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We described a simple one-step process for the synthesis of oleic acid-capped magnetite nanoparticles using the dimethyl sulfoxide(DMSO) to oxidize the precursor Fe~(2+) at 140℃.By adjusting the alkalinity of the reaction system,magnetite nanoparticles with two sizes of 4 and 7 nm could be easily achieved.And the magnetite nanoparticles coated by oleate were well-monodispersed in organic solvent.

  13. Interaction of aqueous caustic with acidic oils

    Energy Technology Data Exchange (ETDEWEB)

    Chiwetelu, C.I.; Hornof, V.; Neale, G.H. (Univ. of Ottawa, Ottawa, ON (Canada))

    High content of native carboxylic acids make heavy oils acidic. It is generally accepted that these acids react with caustic reagents present in floodwater, resulting in the in-situ formation of surface active soap anions. When these adsorb at the oil-water interface, they can drastically lower the interfacial tension to the point where residual oil is mobilized. The most intriguing aspect of these acid/caustic interactions is the dynamic nature of the interfacial tension. Given a sufficiently long time, the dynamic tension would attain an equilibrium state. Measurements were made of the equilibrium interfacial tensions of acidified oleic phases contacted with a wide range of caustic concentrations in the aqueous phase. A novel measurement technique (photomicropendography) was used, and data analysis was carried out by nonlinear regression. The present approach utilizes pre-selected fatty acids in a defined oleic phase, enabling quantification of relevant model parameters and facilitating evaluation of key variables influencing interfacial activity. The acid ionization constant and the equilibrium constant governing the formation of inactive soap species were found to be the most important parameters for systems of oleic and lauric acids dissolved in hexadecane. Regression analysis showed that the acid dissociation constant (pKa) of oleic acid ranged from 6.2 to 6.9 and was dependent on the working acid concentration. For lauric acid, the pKa values were in the range of 9 to 11 depending on the caustic concentration of the aqueous phase. Species aggregation in both the oleic and aqueous phases is mostly responsible for the variations in pKa values. 30 refs., 10 figs., 4 tabs.

  14. Effect of high oleic acid soybean on seed oil, protein concentration, and yield

    Science.gov (United States)

    Soybeans with high oleic acid content are desired by oil processors because of their improved oxidative stability for broader use in food, fuel and other products. However, non-GMO high-oleic soybeans have tended to have low seed yield. The objective of this study was to test non-GMO, high-oleic s...

  15. Polyamidoamine dendrimer and oleic acid-functionalized graphene as biocompatible and efficient gene delivery vectors.

    Science.gov (United States)

    Liu, Xiahui; Ma, Dongmei; Tang, Hao; Tan, Liang; Xie, Qingji; Zhang, Youyu; Ma, Ming; Yao, Shouzhuo

    2014-06-11

    Functionalized graphene has good potential in biomedical applications. To address a better and multiplex design of graphene-based gene vectors, the graphene-oleate-polyamidoamine (PAMAM) dendrimer hybrids were synthesized by the oleic acid adsorption and covalent linkage of PAMAM dendrimers. The micromorphology, electrical charge property, and amount of free amine groups of the graphene-oleate-PAMAM hybrids were characterized, and the peripheral functional groups were identified. The PAMAM dendrimers could be tethered onto graphene surface in high density. The graphene-oleate-PAMAM hybrids exhibit relatively good dispersity and stability in aqueous solutions. To evaluate the potential application of the hybrids in gene delivery vectors, cytotoxicity to HeLa and MG-63 cells and gene (plasmid DNA of enhanced green fluorescent protein) transfection capacity of the hybrids were investigated in detail. The graphene-oleate-PAMAM hybrids show mammalian cell type- and dose-dependent in vitro cytotoxicity. Under the optimal condition, the hybrids possess good biocompatibility and gene transfection capacity. The surface modification of graphene with oleic acid and PAMAM improves the gene transfection efficiency 13 times in contrast to the ultrasonicated graphene. Moreover, the hybrids show better transfection efficiency than the graphene oxide-PAMAM without the oleic acid modification. PMID:24836601

  16. Extraction of Oleic Acid from Moroccan Olive Mill Wastewater

    Science.gov (United States)

    Elkacmi, Reda; Kamil, Noureddine; Bennajah, Mounir; Kitane, Said

    2016-01-01

    The production of olive oil in Morocco has recently grown considerably for its economic and nutritional importance favored by the country's climate. After the extraction of olive oil by pressing or centrifuging, the obtained liquid contains oil and vegetation water which is subsequently separated by decanting or centrifugation. Despite its treatment throughout the extraction process, this olive mill wastewater, OMW, still contains a very important oily residue, always regarded as a rejection. The separated oil from OMW can not be intended for food because of its high acidity of 3.397% which exceeds the international standard for human consumption defined by the standard of the Codex Alimentarius, proving its poor quality. This work gives value addition to what would normally be regarded as waste by the extraction of oleic acid as a high value product, using the technique of inclusion with urea for the elimination of saturated and unsaturated fatty acids through four successive crystallizations at 4°C and 20°C to have a final phase with oleic acid purity of 95.49%, as a biodegradable soap and a high quality glycerin will be produced by the reaction of saponification and transesterification. PMID:26933663

  17. Extraction of Oleic Acid from Moroccan Olive Mill Wastewater

    Directory of Open Access Journals (Sweden)

    Reda Elkacmi

    2016-01-01

    Full Text Available The production of olive oil in Morocco has recently grown considerably for its economic and nutritional importance favored by the country’s climate. After the extraction of olive oil by pressing or centrifuging, the obtained liquid contains oil and vegetation water which is subsequently separated by decanting or centrifugation. Despite its treatment throughout the extraction process, this olive mill wastewater, OMW, still contains a very important oily residue, always regarded as a rejection. The separated oil from OMW can not be intended for food because of its high acidity of 3.397% which exceeds the international standard for human consumption defined by the standard of the Codex Alimentarius, proving its poor quality. This work gives value addition to what would normally be regarded as waste by the extraction of oleic acid as a high value product, using the technique of inclusion with urea for the elimination of saturated and unsaturated fatty acids through four successive crystallizations at 4°C and 20°C to have a final phase with oleic acid purity of 95.49%, as a biodegradable soap and a high quality glycerin will be produced by the reaction of saponification and transesterification.

  18. Oleic acid coated magnetic nano-particles: Synthesis and characterizations

    International Nuclear Information System (INIS)

    Magnetic nano particles of Fe3O4 coated with oleic acid were synthesized using wet chemical route, which involved co-precipitation of Fe2+ and Fe3+ ions. The nano particles were characterized using XRD, TEM, FTIR, TGA and VSM. X-ray diffraction studies showed that nano particles consist of single phase Fe3O4 having inverse spinel structure. The particle size obtained from width of Bragg peak is about 12.6 nm. TEM analysis showed that sizes of nano particles are in range of 6 to 17 nm with a dominant population at 12 - 14 nm. FTIR and TGA analysis showed that -COOH group of oleic acid is bound to the surface of Fe3O4 particles and one has to heat the sample to 278° C to remove the attached molecule from the surface. Further it was seen that Fe3O4 particles exhibit super paramagnetism with a magnetization of about 53 emu/ gm

  19. Oleic acid coated magnetic nano-particles: Synthesis and characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Panda, Biswajit, E-mail: bpanda@mes.ac.in; Goyal, P. S. [Pillai’s Institute of Information Technology, Engineering, Media Studies and Research, Dr. K. M. Vasudevan Pillai’s Campus, New Panvel, 410 206 (India)

    2015-06-24

    Magnetic nano particles of Fe{sub 3}O{sub 4} coated with oleic acid were synthesized using wet chemical route, which involved co-precipitation of Fe{sup 2+} and Fe{sup 3+} ions. The nano particles were characterized using XRD, TEM, FTIR, TGA and VSM. X-ray diffraction studies showed that nano particles consist of single phase Fe{sub 3}O{sub 4} having inverse spinel structure. The particle size obtained from width of Bragg peak is about 12.6 nm. TEM analysis showed that sizes of nano particles are in range of 6 to 17 nm with a dominant population at 12 - 14 nm. FTIR and TGA analysis showed that -COOH group of oleic acid is bound to the surface of Fe{sub 3}O{sub 4} particles and one has to heat the sample to 278° C to remove the attached molecule from the surface. Further it was seen that Fe{sub 3}O{sub 4} particles exhibit super paramagnetism with a magnetization of about 53 emu/ gm.

  20. Aminosilane/oleic acid vesicles as model membranes of protocells.

    Science.gov (United States)

    Douliez, Jean-Paul; Zhendre, Vanessa; Grélard, Axelle; Dufourc, Erick J

    2014-12-16

    Oleic acid vesicles represent good models of membrane protocells that could have existed in prebiotic times. Here, we report the formation, growth polymorphism, and dynamics of oleic acid spherical vesicles (1-10 μm), stable elongated vesicles (>50 μm length; 1-3 μm diameter), and chains of vesicles (pearl necklaces, >50 μm length; 1-3 μm diameter) in the presence of aminopropyl triethoxysilane and guanidine hydrochloride. These vesicles exhibit a remarkable behavior with temperature: spherical vesicles only are observed when keeping the sample at 4 °C for 2 h, and self-aggregated spherical vesicles occur upon freezing/unfreezing (-20/20 °C) samples. Rather homogeneous elongated vesicles are reformed upon heating samples at 80 °C. The phenomenon is reversible through cycles of freezing/heating or cooling/heating of the same sample. Deuterium NMR evidences a chain packing rigidity similar to that of phospholipid bilayers in cellular biomembranes. We expect these bilayered vesicles to be surrounded by a layer of aminosilane oligomers, offering a variant model for membrane protocells. PMID:25420203

  1. Comparison of Different Heterogeneous Catalysts for the Estolide Synthesis from Oleic Acid

    International Nuclear Information System (INIS)

    In this work, different catalysts, namely various loading of perchloric acid on various supports; HClO4/ silica (SiO2), HClO4/ silica gel (SG) and HClO4/ alumina (Al2O3) were tested for the direct addition reaction of oleic acid (OA) to form estolide compound. The reactions were carried out under vacuum (2 mBar) for 10 hours at 70 degree Celsius under solvent less conditions. LC-MS ToF of reaction products results showed chromatographic peaks for the presence of two new estolide compounds, oleic-oleic mono estolide acid (m/z 563.51, as [M-H]-), and oleic-oleic di estolide acid (m/z 845.77 [MH]-). The optimum loading of HClO4 for every support are 15 wt.% HClO4/ SiO2 (SiO215), 10 wt.% HClO4/ SG (SG10) and 35 wt.% HClO4/ Al2O3 (Al35). The SG10 turned out to be the best catalyst , achieving a final conversion of 97.5 % with 79.8 % selectivity to oleic-oleic mono estolide acid and 17.7 % selectivity to oleic-oleic diestolide acid. The activity and selectivity of the SG10 have been investigated and compared with homogeneous HClO4. The optimum catalysts for every support were characterized by various techniques. (author)

  2. The complex tale of the high oleic acid trait in peanut (Arachis hypogaea L.)

    Science.gov (United States)

    Fatty acid composition of oil extracted from peanut (Arachis hypogaea L.) seed is an important quality trait. In particular, a high ratio of oleic (C18:1) relative to linoleic (C18:2) fatty acid (O/L = 10) results in a longer shelf life. Previous reports suggest that the high oleic (~80%) trait wa...

  3. Oleic acid based heterolipid synthesis, characterization and application in self-microemulsifying drug delivery system.

    Science.gov (United States)

    Kalhapure, Rahul S; Akamanchi, Krishnacharya G

    2012-04-01

    There is increasing demand for lipids owing to their use in formulating lipid based drug delivery systems of poorly soluble drugs. The present work discusses the synthesis, characterization of oleic acid based heterolipid and its use as oil in the development of self-microemulsifying drug delivery system (SMEDDS) for parenteral delivery. Synthesis was carried out by Michael addition of tert-butyl acrylate to 3-amino-1-propanol to obtain di-tert-butyl aminopropanol derivative. Reaction of this di-tert-butyl aminopropanol derivative with oleoyl chloride using p-dimethylaminopyridine as a coupling agent gave the desired heterolipid. It was characterized by (1)H NMR, (13)C NMR and MS to confirm the structure. It did not exhibit any measurable cytotoxicity, even up to 80μg/ml concentration. Application in parenteral drug delivery was explored using furosemide (FUR), a BCS class IV drug, as a model. FUR showed three times greater solubility in the heterolipid as compared to oleic acid. SMEDDSs were developed using heterolipid as oily phase, Solutol HS 15(®) as surfactant and ethanol as a co-surfactant. Developed SMEDDS could form spontaneous microemulsion on addition to various aqueous phases with mean globule size <70nm without any phase separation or drug precipitation even after 24h, and exhibited negligible hemolytic potential. PMID:22266534

  4. Measurements of Oleic Acid among Individual kernels Harvested from Test Plots of Purified Runner and Spanish High Oleic Seed

    Science.gov (United States)

    Normal oleic peanuts are often found within commercial lots of high oleic peanuts when sampling among individual kernels. Kernels not meeting high oleic threshold could be true contamination with normal oleic peanuts introduced via poor handling, or they could be immature and not fully expressing th...

  5. Enhanced uptake of water by oxidatively processed oleic acid

    Directory of Open Access Journals (Sweden)

    A. Asad

    2004-07-01

    Full Text Available A quartz crystal microbalance apparatus has been used to measure the room temperature uptake of water vapour by thin films of oleic acid as a function of relative humidity, both before and following exposure of the films to various partial pressures of gas phase ozone. A rapid increase in the water-sorbing ability of the film is observed as its exposure to ozone is increased, followed by a plateau region in which no additional water is taken up. In this fully-processed region the mass of water taken up by the film is about 4 times that of the unprocessed film. Infrared spectra of the films, measured after variable exposures to ozone, show dramatic increases in both the "free" and hydrogen-bonded O-H stretching regions, and a decrease in the intensity of olefinic features. These results are consistent with the formation of an oxygenated polymeric product or products, as well as the gas phase products previously identified.

  6. Amplified spontaneous emission from the exciplex state of a conjugated polymer "PFO" in oleic acid

    Science.gov (United States)

    Idriss, Hajo; Taha, Kamal K.; Aldaghri, O.; Alhathlool, R.; AlSalhi, M. S.; Ibnaouf, K. H.

    2016-09-01

    The amplified spontaneous emission (ASE) characteristics of a conjugated polymer poly (9, 9-dioctylfluorenyl-2, 7-diyl) (PFO) in oleic acid have been studied under different concentrations and temperatures. Here, the ASE spectra of PFO in oleic acid have been obtained using a transverse cavity configuration where the conjugated PFO was pumped by laser pulses from the third harmonic of Nd: YAG laser (355 nm). The PFO in oleic acid produces ASE from an exciplex state - a new molecular species. The obtained results were compared with the PFO in benzene. Such ASE spectra from the exciplex state have not been observed for the PFO in benzene.

  7. In vitro antifungal potentials of bioactive compound oleic acid, 3-(octadecyloxy) propyl ester isolated from Lepidagathis cristata Willd. (Acanthaceae) inflorescence

    Institute of Scientific and Technical Information of China (English)

    Maghdu Nainamohamed Abubacker; Palaniyappan Kamala Devi

    2014-01-01

    Objective: To identify bioactive compound oleic acid, 3-(octadecyloxy) propyl ester from Lepidagathis cristata Willd. (L. cristata) and to assess antifungal potentials of the isolated compound. Methods: Aqueous extracts of L. cristata inflorescence were used for this study. The major bioactive compound isolated was tested for antifungal activities. Results: The major bioactive compound oleic acid, 3-(octadecyloxy) propyl ester was isolated from the inflorescence of L. cristata. The bioactive compound was tested for antifungal potentials and found to be highly effective to plant pathogenic fungi Colletotrichum fulcatum NCBT 146, Fusarium oxysporum NCBT 156 and Rhizoctonia solani NCBT 196 as well as for the human pathogenic fungi Curvularia lunata MTCC 2030 and Microsporum canis MTCC 2820. Conclusions: The results justify the antifungal potentials of both plant and human pathogenic fungi. The plant bioactive compound will be helpful in herbal antifungal formulations.

  8. Lewis Acidic Ionic Liquids As New Addition Catalyst For Oleic Acid To Monoestolide Synthesis

    Directory of Open Access Journals (Sweden)

    Nadia Farhana Adnan

    2011-09-01

    Full Text Available Estolide compound has a large potential in many industrial applications such as biodegradable lubricants and in cosmetic formulation. In this study, monoestolide can be prepared by addition reaction of oleic acid under vacuum-reflux and solvent free condition for 10 hours at 85 °C in the presence of solid zinc chloride anhydrous (ZnCl2, choline chloride (ChCl and ionic liquids (IL ChCl-ZnCl2, ChCl-FeCl3, ChCl-SnCl2, ChCl-CuCl2 as homogenous acid catalysts. These reactions were compared with common homogenous catalyst namely sulfuric acid (H2SO4. The FTIR analysis show that addition reaction using the above catalysts showed the presence of three new peaks at 1732 cm-1 for C=O ester, 967.0 cm-1 for trans-CH=CH and 1176 cm-1 for C-O-C which confirmed the existence of monoestolide. The LC-MS results showed peak for the present of new monoestolides at retention time (tR 12.3 min corresponding to m/z 563.48. Among the IL, ChCl-ZnCl2 surprisingly exhibited higher activity which is 98 % acid oleic conversion and 80 % selective for the synthesis of monoestolides. As a result, this IL gave two potential functions as a solvent as well as a green catalyst for monoestolide synthesis from oleic acid.

  9. Production of Biodiesel from Oleic Acid and Methanol by Reactive Distillation

    Directory of Open Access Journals (Sweden)

    Kusmiyati Kusmiyati

    2010-10-01

    Full Text Available Biodiesel is an alternative diesel fuel that is produced from vegetable oils and animal fats. Generally, it is formed by transesterification reaction of triglycerides in the vegetable oil or animal fat with an alcohol. In this work, esterification reaction was carried out using oleic acid, methanol and sulphuric acid as a catalyst by reactive distillation method. In order to determine the best conditions for biodiesel production by reactive distillation, the experiments were carried out at different temperature (100 oC, 120 oC, 150 oC and 180 oC using methanol/oleic acid molar ratios (1:1, 5:1, 6:1, 7:1, 8:1, catalyst/ oleic acid molar ratios (0.5%wt, 1%wt, 1.5%wt and 2%wt and reaction times (15, 30, 45, 60, 75 and 90 minutes. Results at temperature 180 oC, methanol/ oleic acid molar ratio of 8:1, amount of catalyst 1% for 90 minute reaction time gives the highest conversion of oleic acid above 0.9571. Biodiesel product from oleic acid was analysed by ASTM (American Standard for Testing Material. The results show that the biodiesel produced has the quality required to be a diesel substitute. ©2010 BCREC UNDIP. All rights reserved(Received: 1st January 2010, Revised: 18th March 2010; Accepted: 18th March 2010[How to Cite: K. Kusmiyati, A. Sugiharto. (2010. Production of Biodiesel from Oleic Acid and Methanol by Reactive Distillation. Bulletin of Chemical Reaction Engineering and Catalysis, 5(1: 1-6. doi:10.9767/bcrec.5.1.37.1-6][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.5.1.37.1-6

  10. Production of Biodiesel from Oleic Acid and Methanol by Reactive Distillation

    Directory of Open Access Journals (Sweden)

    Kusmiyati Kusmiyati

    2010-10-01

    Full Text Available Biodiesel is an alternative diesel fuel that is produced from vegetable oils and animal fats. Generally, it is formed by transesterification reaction of triglycerides in the vegetable oil or animal fat with an alcohol. In this work, esterification reaction was carried out using oleic acid, methanol and sulphuric acid as a catalyst by reactive distillation method. In order to determine the best conditions for biodiesel production by reactive distillation, the experiments were carried out at different temperature (100 0C, 120 0C, 150 0C and 180 0C using methanol/oleic acid molar ratios (1:1, 5:1, 6:1, 7:1, 8:1, catalyst/ oleic acid molar ratios (0.5%wt, 1%wt, 1.5%wt and 2%wt and reaction times (15, 30, 45, 60, 75 and 90 minutes. Results at temperature 180 0C, methanol/ oleic acid molar ratio of 8:1, amount of catalyst 1% for 90 minute reaction time gives the highest conversion of oleic acid above 0.9571. Biodiesel product from oleic acid was analysed by ASTM (American Standard for Testing Material. The results show that the biodiesel produced has the quality required to be a diesel substitute. © 2010 BCREC UNDIP. All rights reserved. (Received: 1st January 2010, Revised: 18th March 2010; Accepted: 18th March 2010[How to Cite: K. Kusmiyati, A. Sugiharto. (2010. Production of Biodiesel from Oleic Acid and Methanol by Reactive Distillation. Bulletin of Chemical Reaction Engineering and Catalysis, 5(1: 1-6. doi:10.9767/bcrec.5.1.7103.1-6][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.5.1.7103.1-6 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/7103

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

    Science.gov (United States)

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

    2016-05-01

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

  12. A complex of equine lysozyme and oleic acid with bactericidal activity against Streptococcus pneumoniae.

    Directory of Open Access Journals (Sweden)

    Emily A Clementi

    Full Text Available HAMLET and ELOA are complexes consisting of oleic acid and two homologous, yet functionally different, proteins with cytotoxic activities against mammalian cells, with HAMLET showing higher tumor cells specificity, possibly due to the difference in propensity for oleic acid binding, as HAMLET binds 5-8 oleic acid molecules per protein molecule and ELOA binds 11-48 oleic acids. HAMLET has been shown to possess bactericidal activity against a number of bacterial species, particularly those with a respiratory tropism, with Streptococcus pneumoniae displaying the greatest degree of sensitivity. We show here that ELOA also displays bactericidal activity against pneumococci, which at lower concentrations shows mechanistic similarities to HAMLET's bactericidal activity. ELOA binds to S. pneumoniae and causes perturbations of the plasma membrane, including depolarization and subsequent rupture, and activates an influx of calcium into the cells. Selective inhibition of calcium channels and sodium/calcium exchange activity significantly diminished ELOA's bactericidal activity, similar to what we have observed with HAMLET. Finally, ELOA-induced death was also accompanied by DNA fragmentation into high molecular weight fragments - an apoptosis-like morphological phenotype that is seen during HAMLET-induced death. Thus, in contrast to different mechanisms of eukaryote cell death induced by ELOA and HAMLET, these complexes are characterized by rather similar activities towards bacteria. Although the majority of these events could be mimicked using oleic acid alone, the concentrations of oleic acid required were significantly higher than those present in the ELOA complex, and for some assays, the results were not identical between oleic acid alone and the ELOA complex. This indicates that the lipid, as a common denominator in both complexes, is an important component for the complexes' bactericidal activities, while the proteins are required both to solubilize

  13. Dietary non-esterified oleic Acid decreases the jejunal levels of anorectic N-acylethanolamines

    DEFF Research Database (Denmark)

    Diep, Thi Ai; Madsen, Andreas N; Krogh-Hansen, Sandra;

    2014-01-01

    mice respond to dietary fat (olive oil) by reducing levels of anorectic NAEs, and 3) whether dietary non-esterified oleic acid also can decrease levels of anorectic NAEs in mice. We are searching for the fat sensor in the intestine, which mediates the decreased levels of anorectic NAEs. METHODS: Male...... of anorectic NAEs in mice. CONCLUSIONS: These results suggest that the down-regulation of the jejunal level of anorectic NAEs by dietary fat is not restricted to rats, and that the fatty acid component oleic acid, in dietary olive oil may be sufficient to mediate this regulation. Thus, a fatty acid sensor may...

  14. Development and validation of a GC–FID method for quantitative analysis of oleic acid and related fatty acids

    OpenAIRE

    Honggen Zhang; Zhenyu Wang; Oscar Liu

    2015-01-01

    Oleic acid is a common pharmaceutical excipient that has been widely used in various dosage forms. Gas chromatography (GC) has often been used as the quantitation method for fatty acids normally requiring a derivatization step. The aim of this study was to develop a simple, robust, and derivatization-free GC method that is suitable for routine analysis of all the major components in oleic acid USP-NF (United States Pharmacopeia-National Formulary) material. A gas chromatography–flame ionizati...

  15. Oleic, Linoleic and Linolenic Acids Increase ROS Production by Fibroblasts via NADPH Oxidase Activation

    Science.gov (United States)

    Hatanaka, Elaine; Dermargos, Alexandre; Hirata, Aparecida Emiko; Vinolo, Marco Aurélio Ramirez; Carpinelli, Angelo Rafael; Newsholme, Philip; Armelin, Hugo Aguirre; Curi, Rui

    2013-01-01

    The effect of oleic, linoleic and γ-linolenic acids on ROS production by 3T3 Swiss and Rat 1 fibroblasts was investigated. Using lucigenin-amplified chemiluminescence, a dose-dependent increase in extracellular superoxide levels was observed during the treatment of fibroblasts with oleic, linoleic and γ-linolenic acids. ROS production was dependent on the addition of β-NADH or NADPH to the medium. Diphenyleneiodonium inhibited the effect of oleic, linoleic and γ-linolenic acids on fibroblast superoxide release by 79%, 92% and 82%, respectively. Increased levels of p47phox phosphorylation due to fatty acid treatment were detected by Western blotting analyses of fibroblast proteins. Increased p47phox mRNA expression was observed using real-time PCR. The rank order for the fatty acid stimulation of the fibroblast oxidative burst was as follows: γ-linolenic > linoleic > oleic. In conclusion, oleic, linoleic and γ-linolenic acids stimulated ROS production via activation of the NADPH oxidase enzyme complex in fibroblasts. PMID:23579616

  16. Pressure-induced Phase Transition in Oleic Acid Studied by Raman Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    FAN Ya; ZHOU Jing; LI Shuang; GUAN Fu-Ying; XU Da-Peng

    2011-01-01

    High-pressure Raman studies up to 0.84 GPa are performed on oleic acid.Spectral analysis indicates that oleic acid undergoes a pressure-induced phase transition in the 0.29-0.36 GPa range.Only one high-pressure phase below 0.84 GPa is present,in which the polymethylene chains take the ordered all-trans conformation,with the methyl end of the chains exhibiting the ordered tt chain-end conformation and the olefin group taking the skewcis-skew' conformation.The conformational characters of the oleic acid molecule show that the high-pressure phase is the same as the low-temperature crystalline γ phase.The pressure-induced phase transition is typical of first-order transitions and the transition path during compression is different from that during cooling.Oleic acid (C1sH34O2) is one of the unsaturated fatty acids that appear naturally in a liquid state.It is one of the most common components of human diets,preventing coronary disease and breast cancer and benefiting people with diabetes.[1] A molecule of oleic acid possesses a carbon double bond,C =C,which leads to the occurrence of a phase transition when pressure is applied.[2] Therefore,the significance of high-pressure processing has recently increased as an alternative method of food preservation.So far some physical properties of oleic acid under pressures below 1 GPa have been investigated using a piston-cylinder device as a high-pressure apparatus.[2-10] However,no high-pressure Raman or any other in-situ experimental research on pressure-induced phase transition in oleic acid has been reported.In addition,the freezing point of oleic acid is 13.3℃,below which oleic acid crystallizes in three forms,namely,α,β and γ[11-17]%High-pressure Raman studies up to 0.84 Gpa are performed on oleic acid. Spectral analysis indicates that oleic acid undergoes a pressure-induced phase transition in the 0.29-0.36 Gpa range. Only one high-pressure phase below 0.84 Gpa is present, in which the polymethylene chains take the

  17. Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications

    Science.gov (United States)

    Soares, Paula I. P.; Laia, César A. T.; Carvalho, Alexandra; Pereira, Laura C. J.; Coutinho, Joana T.; Ferreira, Isabel M. M.; Novo, Carlos M. M.; Borges, João Paulo

    2016-10-01

    Iron oxide nanoparticles (Fe3O4, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of -120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

  18. Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

    Science.gov (United States)

    Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

    2016-03-01

    Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

  19. Performace Test and Engine Emission on Acid Oleic Oxygenated as Additives Petrol

    OpenAIRE

    Irfan Wahyudi; Abdul Amir Hassan Kadhum; Yusoff Ali

    2010-01-01

    The objective of this study is to investigate the effect of oxygenated oleic acid additives in standard petrol on the engine performance and the exhaust emissions. The 4-stroke 1.5 litre engine was used on the engine test bed coupled to eddy current electric dynamometer which is also connected to CADET V12 control system and exhaust gas analyser IMR2000/2000P. The oxygenated oleic acid additives used for this experiment is fixed at 0.2% by volume due to limited quantity available. Two types...

  20. Preparation and UV-light Absorption Property of Oleic Acid Surface Modified ZnO Nanoparticles

    Institute of Scientific and Technical Information of China (English)

    KANG Jong-hun; GUO Yu-peng; CHEN Yue; WANG Zi-chen

    2011-01-01

    Syntheses of zince oxide(ZnO) nanoparticles by direct precipitation and surface modification with oleic acid were reported. ZnO nanoparticles were characterized via X-ray diffractometry(XRD), transmission electron microscopy(TEM), infrared spectroscopy(IR) and UV-Vis spectroscopy. The prepared ZnO nanoparticles were nearly spherical and highly crystalline with an average size of 29 nm. In addition, high UV-light absorption properties of oleic acid surface modified ZnO nanoparticles were successfully obtained for a dispersion of ZnO nanoparticles in ethanol.

  1. Development and validation of a GC–FID method for quantitative analysis of oleic acid and related fatty acids

    Directory of Open Access Journals (Sweden)

    Honggen Zhang

    2015-08-01

    Full Text Available Oleic acid is a common pharmaceutical excipient that has been widely used in various dosage forms. Gas chromatography (GC has often been used as the quantitation method for fatty acids normally requiring a derivatization step. The aim of this study was to develop a simple, robust, and derivatization-free GC method that is suitable for routine analysis of all the major components in oleic acid USP-NF (United States Pharmacopeia-National Formulary material. A gas chromatography–flame ionization detection (GC–FID method was developed for direct quantitative analysis of oleic acid and related fatty acids in oleic acid USP-NF material. Fifteen fatty acids were separated using a DB-FFAP (nitroterephthalic acid modified polyethylene glycol capillary GC column (30 m×0.32 mm i.d. with a total run time of 20 min. The method was validated in terms of specificity, linearity, precision, accuracy, sensitivity, and robustness. The method can be routinely used for the purpose of oleic acid USP-NF material analysis.

  2. Synthesis of oleic acid-stabilized silver nanoparticles and analysis of their antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Le, Anh-Tuan, E-mail: tuanla-hast@mail.hut.edu.vn [Department of Nanoscience and Nanotechnology, Hanoi Advanced School of Science and Technology (HAST), Hanoi University of Technology, F Building, 40 Ta Quang Buu street, Hanoi (Viet Nam); Tam, Le Thi; Tam, Phuong Dinh; Huy, P.T [Department of Nanoscience and Nanotechnology, Hanoi Advanced School of Science and Technology (HAST), Hanoi University of Technology, F Building, 40 Ta Quang Buu street, Hanoi (Viet Nam); Huy, Tran Quang [National Institute of Hygiene and Epidemiology (NIHE), 01 Yersin, Hai Ba Trung District, Hanoi (Viet Nam); Van Hieu, Nguyen [International Training Institute of Materials Science (ITIMS), Hanoi University of Technology, No 1 Dai Co Viet, Hanoi (Viet Nam); Kudrinskiy, A A; Krutyakov, Yu A [Department of Chemistry, M V Lomonosov Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation)

    2010-07-20

    The development of new and simple green chemical methods for synthesizing colloidal solutions of functional nanoparticles is desirable for environment-friendly applications. In the present work, we report a feasible method for synthesizing colloidal solutions of silver nanoparticles (Ag NPs) based on the modified Tollens technique. The Ag NPs were stabilized by using oleic acid as a surfactant and were produced for the first time by the reduction of silver ammonium complex [Ag(NH{sub 3}){sub 2}]{sup +}{sub (aq)} by glucose with UV irradiation treatment. A stable and nearly monodisperse aqueous Ag NPs solution with average-sized particles ({approx} 9-10 nm) was obtained. The Ag NPs exhibited high antibacterial activity against both Gram-negative Escherichia Coli (E. coli) and Gram-positive Staphylococcus aureus bacteria. Electron microscopic images and analyses provided further insights into the interaction and bactericidal mechanism of the Ag NPs. The proposed method of synthesis is an effective way to produce highly bactericidal colloidal solutions for medical, microbiological, and industrial applications.

  3. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum.

    Science.gov (United States)

    Gurunathan, Abinaya; Senguttuvan, Jamuna; Paulsamy, S

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. The chitinase activity of isolated compound was assessed by using purified β-N-acetyl glucosaminidase (chitinase). Ecdysone 20-monooxygenase assay (radioimmuno assay) was made using the same larval stage of A. aegyptiand C. quinquefasciatus. The results were compared with the crude methanol extract of the whole plant. The isolated compound, oleic acid, eicosyl ester was found to be the most effective larvicide against A. aegypti (LC50/24 h -8.51 ppm) and C. quinquefasciatus (LC50/24 h - 12.5 ppm) than the crude methanol extract (LC50/24 h - 257.03 ppm and LC50/24 h - 281.83 ppm, respectively). The impact of oleic acid, eicosyl ester on reducing the activity of chitinase and ecdysone 20-monooxygenase was most prominent in both the target species, A. aegyptiand C. quinquefasciatus than the control. The results therefore suggest that the compound, oleic acid, eicosyl ester from Thalictrum javanicum may be considered as a potent source of mosquito larvicidal property. PMID:27168688

  4. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum.

    Science.gov (United States)

    Gurunathan, Abinaya; Senguttuvan, Jamuna; Paulsamy, S

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. The chitinase activity of isolated compound was assessed by using purified β-N-acetyl glucosaminidase (chitinase). Ecdysone 20-monooxygenase assay (radioimmuno assay) was made using the same larval stage of A. aegyptiand C. quinquefasciatus. The results were compared with the crude methanol extract of the whole plant. The isolated compound, oleic acid, eicosyl ester was found to be the most effective larvicide against A. aegypti (LC50/24 h -8.51 ppm) and C. quinquefasciatus (LC50/24 h - 12.5 ppm) than the crude methanol extract (LC50/24 h - 257.03 ppm and LC50/24 h - 281.83 ppm, respectively). The impact of oleic acid, eicosyl ester on reducing the activity of chitinase and ecdysone 20-monooxygenase was most prominent in both the target species, A. aegyptiand C. quinquefasciatus than the control. The results therefore suggest that the compound, oleic acid, eicosyl ester from Thalictrum javanicum may be considered as a potent source of mosquito larvicidal property.

  5. Evaluation of mosquito repellent activity of isolated oleic acid, eicosyl ester from Thalictrum javanicum

    Directory of Open Access Journals (Sweden)

    Abinaya Gurunathan

    2016-01-01

    Full Text Available To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicumand to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti(dengue vector and Culex quinquefasciatus(filarial vector. Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. The chitinase activity of isolated compound was assessed by using purified β-N-acetyl glucosaminidase (chitinase. Ecdysone 20-monooxygenase assay (radioimmuno assay was made using the same larval stage of A. aegyptiand C. quinquefasciatus. The results were compared with the crude methanol extract of the whole plant. The isolated compound, oleic acid, eicosyl ester was found to be the most effective larvicide against A. aegypti (LC50/24 h -8.51 ppm and C. quinquefasciatus (LC50/24 h - 12.5 ppm than the crude methanol extract (LC50/24 h - 257.03 ppm and LC50/24 h - 281.83 ppm, respectively. The impact of oleic acid, eicosyl ester on reducing the activity of chitinase and ecdysone 20-monooxygenase was most prominent in both the target species, A. aegyptiand C. quinquefasciatusthan the control. The results therefore suggest that the compound, oleic acid, eicosyl ester from Thalictrum javanicummay be considered as a potent source of mosquito larvicidal property.

  6. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum

    Science.gov (United States)

    Gurunathan, Abinaya; Senguttuvan, Jamuna; Paulsamy, S.

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. The chitinase activity of isolated compound was assessed by using purified β-N-acetyl glucosaminidase (chitinase). Ecdysone 20-monooxygenase assay (radioimmuno assay) was made using the same larval stage of A. aegyptiand C. quinquefasciatus. The results were compared with the crude methanol extract of the whole plant. The isolated compound, oleic acid, eicosyl ester was found to be the most effective larvicide against A. aegypti (LC50/24 h -8.51 ppm) and C. quinquefasciatus (LC50/24 h - 12.5 ppm) than the crude methanol extract (LC50/24 h - 257.03 ppm and LC50/24 h - 281.83 ppm, respectively). The impact of oleic acid, eicosyl ester on reducing the activity of chitinase and ecdysone 20-monooxygenase was most prominent in both the target species, A. aegyptiand C. quinquefasciatus than the control. The results therefore suggest that the compound, oleic acid, eicosyl ester from Thalictrum javanicum may be considered as a potent source of mosquito larvicidal property. PMID:27168688

  7. Use of capillary electrophoresis to determine oleic and linoleic acid content of peanut seed

    Science.gov (United States)

    A common consumer complaint regarding peanut products is one involving short shelf life and rapid rancidity. Peanut cultivars with elevated oleic acid content (and decreased linoleic content) have been shown to have an increased shelf life and thus have become largely preferred by peanut processors...

  8. Interconnection of nanoparticles within 2D superlattices of PbS/oleic acid thin films.

    Science.gov (United States)

    Simon, Paul; Bahrig, Lydia; Baburin, Igor A; Formanek, Petr; Röder, Falk; Sickmann, Jan; Hickey, Stephen G; Eychmüller, Alexander; Lichte, Hannes; Kniep, Rüdiger; Rosseeva, Elena

    2014-05-21

    Make it connected! 2D close-packed layers of inorganic nanoparticles are interconnected by organic fibrils of oleic acid as clearly visualized by electron holography. These fibrils can be mineralised by PbS to transform an organic-inorganic framework to a completely interconnected inorganic semiconducting 2D array.

  9. INTERESTERIFICATION OF MILK-FAT WITH OLEIC-ACID CATALYZED BY IMMOBILIZED RHIZOPUS-ORYZAE LIPASE

    NARCIS (Netherlands)

    OBA, T; WITHOLT, B

    1994-01-01

    Milk fat was interesterified with oleic acid by catalysis of an immobilized lipase in a microaqueous two-phase system. A commercial lipase from Rhizopus oryzae and a controlled pore glass carrier were selected for preparation of an immobilized lipase. The prepared immobilized lipase showed a Michael

  10. Development of a Controlled Release of Salicylic Acid Loaded Stearic Acid-Oleic Acid Nanoparticles in Cream for Topical Delivery

    Directory of Open Access Journals (Sweden)

    J. O. Woo

    2014-01-01

    Full Text Available Lipid nanoparticles are colloidal carrier systems that have extensively been investigated for controlled drug delivery, cosmetic and pharmaceutical applications. In this work, a cost effective stearic acid-oleic acid nanoparticles (SONs with high loading of salicylic acid, was prepared by melt emulsification method combined with ultrasonication technique. The physicochemical properties, thermal analysis and encapsulation efficiency of SONs were studied. TEM micrographs revealed that incorporation of oleic acid induces the formation of elongated spherical particles. This observation is in agreement with particle size analysis which also showed that the mean particle size of SONs varied with the amount of OA in the mixture but with no effect on their zeta potential values. Differential scanning calorimetry analysis showed that the SONs prepared in this method have lower crystallinity as compared to pure stearic acid. Different amount of oleic acid incorporated gave different degree of perturbation to the crystalline matrix of SONs and hence resulted in lower degrees of crystallinity, thereby improving their encapsulation efficiencies. The optimized SON was further incorporated in cream and its in vitro release study showed a gradual release for 24 hours, denoting the incorporation of salicylic acid in solid matrix of SON and prolonging the in vitro release.

  11. Oleic acid induces smooth muscle foam cell formation and enhances atherosclerotic lesion development via CD36

    OpenAIRE

    Tang Bing; Li; Yang Dachun; Ma Shuangtao; Yang Yongjian

    2011-01-01

    Abstract Background Elevated plasma free fatty acid (FFA) levels have been linked to the development of atherosclerosis. However, how FFA causes atherosclerosis has not been determined. Because fatty acid translocase (FAT/CD36) is responsible for the uptake of FFA, we hypothesized that the atherogenic effects of FFA may be mediated via CD36. Results We tested this hypothesis using cultured rat aortic smooth muscle cells (SMCs) treated with oleic acid (OA). We found that OA induces lipid accum...

  12. Development of marker-free transgenic Jatropha plants with increased levels of seed oleic acid

    Directory of Open Access Journals (Sweden)

    Qu Jing

    2012-02-01

    Full Text Available Abstract Background Jatropha curcas is recognized as a new energy crop due to the presence of the high amount of oil in its seeds that can be converted into biodiesel. The quality and performance of the biodiesel depends on the chemical composition of the fatty acids present in the oil. The fatty acids profile of the oil has a direct impact on ignition quality, heat of combustion and oxidative stability. An ideal biodiesel composition should have more monounsaturated fatty acids and less polyunsaturated acids. Jatropha seed oil contains 30% to 50% polyunsaturated fatty acids (mainly linoleic acid which negatively impacts the oxidative stability and causes high rate of nitrogen oxides emission. Results The enzyme 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine delta 12-desaturase (FAD2 is the key enzyme responsible for the production of linoleic acid in plants. We identified three putative delta 12 fatty acid desaturase genes in Jatropha (JcFAD2s through genome-wide analysis and downregulated the expression of one of these genes, JcFAD2-1, in a seed-specific manner by RNA interference technology. The resulting JcFAD2-1 RNA interference transgenic plants showed a dramatic increase of oleic acid (> 78% and a corresponding reduction in polyunsaturated fatty acids (Jatropha had around 37% oleic acid and 41% polyunsaturated fatty acids. This indicates that FAD2-1 is the major enzyme responsible for converting oleic acid to linoleic acid in Jatropha. Due to the changes in the fatty acids profile, the oil of the JcFAD2-1 RNA interference seed was estimated to yield a cetane number as high as 60.2, which is similar to the required cetane number for conventional premium diesel fuels (60 in Europe. The presence of high seed oleic acid did not have a negative impact on other Jatropha agronomic traits based on our preliminary data of the original plants under greenhouse conditions. Further, we developed a marker-free system to generate the transgenic Jatropha

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  14. Influence of Oleic Acid on Rumen Fermentation and Fatty Acid Formation In Vitro.

    Science.gov (United States)

    Wu, Duanqin; Xu, Liwei; Tang, Shaoxun; Guan, Leluo; He, Zhixiong; Guan, Yongjuan; Tan, Zhiliang; Han, Xuefeng; Zhou, Chuanshe; Kang, Jinhe; Wang, Min

    2016-01-01

    A series of batch cultures were conducted to investigate the effects of oleic acid (OA) on in vitro ruminal dry matter degradability (IVDMD), gas production, methane (CH4) and hydrogen (H2) production, and proportion of fatty acids. Rumen fluid was collected from fistulated goats, diluted with incubation buffer, and then incubated with 500 mg Leymus chinensis meal supplemented with different amounts of OA (0, 20, 40, and 60 mg for the CON, OA20, OA40 and OA60 groups, respectively). Incubation was carried out anaerobically at 39°C for 48 h, and the samples were taken at 12, 24 and 48 h and subjected to laboratory analysis. Supplementation of OA decreased IVDMD, the cumulative gas production, theoretical maximum of gas production and CH4 production, but increased H2 production. However, no effect was observed on any parameters of rumen fermentation (pH, ammonia, production of acetate, propionate and butyrate and total volatile fatty acid production). The concentrations of some beneficial fatty acids, such as cis monounsaturated fatty acids and conjugated linoleic acid (CLA) were higher (P methane production and increase the amount of some beneficial fatty acids in vitro. PMID:27299526

  15. Influence of Oleic Acid on Rumen Fermentation and Fatty Acid Formation In Vitro

    Science.gov (United States)

    Tang, Shaoxun; Guan, Leluo; He, Zhixiong; Guan, Yongjuan; Tan, Zhiliang; Han, Xuefeng; Zhou, Chuanshe; Kang, Jinhe; Wang, Min

    2016-01-01

    A series of batch cultures were conducted to investigate the effects of oleic acid (OA) on in vitro ruminal dry matter degradability (IVDMD), gas production, methane (CH4) and hydrogen (H2) production, and proportion of fatty acids. Rumen fluid was collected from fistulated goats, diluted with incubation buffer, and then incubated with 500 mg Leymus chinensis meal supplemented with different amounts of OA (0, 20, 40, and 60 mg for the CON, OA20, OA40 and OA60 groups, respectively). Incubation was carried out anaerobically at 39°C for 48 h, and the samples were taken at 12, 24 and 48 h and subjected to laboratory analysis. Supplementation of OA decreased IVDMD, the cumulative gas production, theoretical maximum of gas production and CH4 production, but increased H2 production. However, no effect was observed on any parameters of rumen fermentation (pH, ammonia, production of acetate, propionate and butyrate and total volatile fatty acid production). The concentrations of some beneficial fatty acids, such as cis monounsaturated fatty acids and conjugated linoleic acid (CLA) were higher (P < 0.05) from OA groups than those from the control group at 12 h incubation. In summary, these results suggest that the OA supplementation in diet can reduce methane production and increase the amount of some beneficial fatty acids in vitro. PMID:27299526

  16. Production of Biodiesel from Oleic Acid and Methanol by Reactive Distillation

    OpenAIRE

    Kusmiyati Kusmiyati; Agung Sugiharto

    2010-01-01

    Biodiesel is an alternative diesel fuel that is produced from vegetable oils and animal fats. Generally, it is formed by transesterification reaction of triglycerides in the vegetable oil or animal fat with an alcohol. In this work, esterification reaction was carried out using oleic acid, methanol and sulphuric acid as a catalyst by reactive distillation method. In order to determine the best conditions for biodiesel production by reactive distillation, the experiments were carried out at di...

  17. Structure and friction of stearic acid and oleic acid films adsorbed on iron oxide surfaces in squalane.

    Science.gov (United States)

    Doig, Michael; Warrens, Chris P; Camp, Philip J

    2014-01-14

    The structure and friction of fatty acid surfactant films adsorbed on iron oxide surfaces lubricated by squalane are examined using large-scale molecular dynamics simulations. The structures of stearic acid and oleic acid films under static and shear conditions, and at various surface coverages, are described in detail, and the effects of unsaturation in the tail group are highlighted. At high surface coverage, the measured properties of stearic acid and oleic acid films are seen to be very similar. At low and intermediate surface coverages, the presence of a double bond, as in oleic acid, is seen to give rise to less penetration of lubricant in to the surfactant film and less layering of the lubricant near to the film. The kinetic friction coefficient is measured as a function of shear rate within the hydrodynamic (high shear rate) lubrication regime. Lubricant penetration and layering are observed to be correlated with friction coefficient. The friction coefficient with oleic acid depends only weakly on surface coverage, while stearic acid admits more lubricant penetration, and its friction coefficient increases significantly with decreasing surface coverage. Connections between film structure and friction are discussed.

  18. Oleic Acid Based Polyesters of Trimethylolpropane and Pentaerythritol for Bio lubricant Application

    International Nuclear Information System (INIS)

    The production of polyesters based on oleic acid and trimethylolpropane (TMP) or pentaerythritol (PE) as potential bio lubricant were carried out. The esterification processes between oleic acid with TMP or PE were carried out using sulfuric acid as a catalyst. The esterification process produced high yield between 92 %-94 % w/w respectively. The formation of polyesters was confirmed using gas chromatography (GC-FID), Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR). The polyesters were analyzed for basic lubrication physicochemical properties. The results showed that polyesters of both TMP and PE having high viscosity index between 200-309, good pour points ranging from -42 to -59 degree Celsius and high flash points of 280 - 300 degree Celsius respectively. The polyesters also showed good thermal oxidative stability with TGA onset temperatures above 180 degree Celsius. In general both products are plausible to be used as bio lubricant for industrial application. (author)

  19. Synthesis, Characterization, and Tribological Behavior of Oleic Acid Capped Graphene Oxide

    Directory of Open Access Journals (Sweden)

    Tiedan Chen

    2014-01-01

    Full Text Available Graphene oxide (GO nanosheets were prepared by modified Hummers and Offeman methods. Furthermore, oleic acid (OA capped graphene oxide (OACGO nanosheets were prepared and characterized by means of Fourier transform-infrared spectroscopy (FT-IR, transmission electron microscopy (TEM, and X-ray diffraction (XRD. At the same time, the friction and wear properties of OA capped graphite powder (OACG, OACGO, and oleic acid capped precipitate of graphite (OACPG as additives in poly-alpha-olefin (PAO were compared using four-ball tester and SRV-1 reciprocating ball-on-disc friction and wear tester. By the addition of OACGO to PAO, the antiwear ability was improved and the friction coefficient was decreased. Also, the tribological mechanism of the GO was investigated.

  20. Oleic acid-grafted chitosan/graphene oxide composite coating for corrosion protection of carbon steel.

    Science.gov (United States)

    Fayyad, Eman M; Sadasivuni, Kishor Kumar; Ponnamma, Deepalekshmi; Al-Maadeed, Mariam Al Ali

    2016-10-20

    An anticorrosion coating film based on the formation of nanocomposite coating is reported in this study. The composite consisted of chitosan (green matrix), oleic acid, and graphene oxide (nano filler). The nanocomposite coating was arranged on the surface of carbon steel, and the corrosion resistance was monitored using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP). Compared to the pure chitosan (CS) coating, the corrosion resistance of oleic acid-modified chitosan/graphene oxide film (CS/GO-OA) is increased by 100 folds. Since the well-dispersed smart grafted nanolayers delayed the penetration rate of corrosive species and thus maintained long term anticorrosive stability which is correlated with hydrophobicity and permeability. PMID:27474635

  1. Chemical Characterization of Stabilized and Carbonized Polyacrylonitrile (PAN Fibers Treated with Oleic Acid.

    Directory of Open Access Journals (Sweden)

    Salleh Shahrul Nizam Md

    2014-07-01

    Full Text Available Polyacrylonitrile (PAN fiber is the best precursor for carbon fibers due to high carbon content after heat treatment. After the polymer was spun into fibers, the fibers will undergo pretreatment process with chemical solution known as post spinning treatment. Post spinning will directly affect conversion of PAN fiber to carbon fiber. Oleic acid was used as post spinning treatment chemical solution to PAN fibers. The pretreated PAN fiber will be heated at 250°C and 800°C. The fibers were studied using Fourier Transform Infra-Red (FTIR, X-ray Photoelectron Spectroscopy (XPS and DSC to study the chemical change during heat treatment. PAN fibers treated with oleic acid have reduced the cyclization energy and increase oxygen and carbon content leading to high performance carbon fibers.

  2. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum

    OpenAIRE

    Abinaya Gurunathan; Jamuna Senguttuvan; S Paulsamy

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. Th...

  3. Design and evaluation of Lumefantrine – Oleic Acid Self Nanoemulsifying Ionic Complex for Enhanced Dissolution

    Directory of Open Access Journals (Sweden)

    Pradeep Vavia

    2013-03-01

    Full Text Available Background:Lumefantrine, an antimalarial molecule has very low and variable bioavailability owing to its extremely poor solubility in water. It is recommended to be taken with milk to enhance its solubility and bioavailability. The aim of present study was to develop a Self Nanoemulsifying Delivery system (SNEDs of lumefantrine (LF to achieve rapid and complete dissolution independent of food-fat and surfactant in dissolution media.Methods:Solubility of LF in oil, co-solvent/co-surfactant and surfactant solution and emulsification efficiency of surfactant were analyzed to optimize the LF loaded self nanoemulsifying preconcentrate. Effect of LF-oleic acid complexation on emulsification, droplet size, zeta potential and dissolution were investigated. Effect of milk concentration and fat content on saturation solubility and dissolution of LF was investigated. Dissolution of marketed formulation and LF-SNEDs was carried out in pH 1.2 and pH 6.8 phosphate buffer.Results:LF exhibited very high solubility in oleic acid owing to complexation between tertiary amine of LF and carboxyl group of oleic acid (OA. Cremophore EL and medium chain monoglyceride were selected surfactant and co-surfactant, respectively. Significantly smaller droplet size (37 nm, shift in zeta potential from negative to positive value, very high drug loading in lipid based system (> 10%, no precipitation after dissolution are the major distinguish characteristics contributed by LF-OA complex in the SNED system. Saturation solubility and dissolution study in milk containing media pointed the significant increment in solubility of LF in the presence of milk-food fat. LF-SNEDs showed > 90% LF release within 30 min in pH 1.2 while marketed tablet showed almost 0% drug release.Conclusion:Self nanoemulsification promoting ionic complexation between basic drug and oleic acid hold great promise in enhancing solubility of hydrophobic drugs.

  4. Effect of partial liquid ventilation on oleic acid-induced inflammatory responses in piglets

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; WANG Qiang; LIU Ying-long; LI Xiao-feng; LI Jian-an; L(U) Xiao-dong; LING Feng; LIU Ai-jun; FAN Xiang-ming

    2010-01-01

    Background Pediatric patients are susceptible to lung injury.Acute lung injury (ALI) in children often results in a high mortality.Partial liquid ventilation (PLV) has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury models.This study aimed to examine the hypothesis that PLV would attenuate the production of local and systemic cytokines in an immature piglet model of ALI induced by oleic acid (OA).Methods Twelve Chinese immature piglets were induced to develop ALI by oleic acid.The animals were randomly assigned to two groups (n=6): (1) conventional mechanical ventilation (MV) group and (2) PLV with FC-77 (10 ml/kg) group.Results Compared with MV group, PLV group got better cardiopulmonary variables (P <0.05).These variables included heart rate, mean blood pressure, blood pH, partial pressure of arterial oxygen (PaO2), PaO2/FiO2 and partial pressure of arterial carbon dioxide (PaCO2).Partial liquid ventilation reduced IL-1β, IL-6, IL-10 and TN F-α both in plasma and tissue concentrations compared with MV group (P <0.05).Conclusions Partial liquid ventilation provides protective effects against inflammatory responses in the lungs of oleic acid-induced immature piglets.

  5. A novel, stable and reproducible acute lung injury model induced by oleic acid in immature piglet

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; LING Feng; ZHANG Yan-bo; LIU Ai-jun; LIU Dong-hai; QIAO Chen-hui; WANG Qiang; LIU Ying-long

    2011-01-01

    Background Young children are susceptible to pulmonary injury,and acute lung injury (ALl) often results in a high mortality and financial costs in pediatric patients.A good ALl model will help us to gain a better understanding of the real pathophysiological picture and to evaluate novel treatment approaches to acute respiratory distress syndrome (ARDS) more accurately and liberally.This study aimed to establish a hemodynamically stable and reproducible model with ALl in piglet induced by oleic acid.Methods Six Chinese mini-piglets were used to establish ALl models by oleic acid.Hemodynamic and pulmonary function data were measured.Histopathological assessment was performed.Results Mean blood pressure,heart rate (HR),cardiac output (CO),central venous pressure (CVP) and left atrial pressure (LAP) were sharply decreased after oleic acid given,while the mean pulmonary arterial pressure (MPAP) was increased in comparison with baseline (P <0.05).pH,arterial partial pressure of O2 (PaO2),PaO2/inspired O2 fraction (FiO2) and lung compliance decreased,while PaCO2 and airway pressure increased in comparison with baseline (P <0.05).The lung histology showed severe inflammation,hyaline membranes,intra-alveolar and interstitial hemorrhage.Conclusion This experiment established a stable model which allows for a diversity of studies on early lung injury.

  6. The kinetics of the solidification of highly supersaturated solutions of palmitic acid in oleic acid: a comparison between two models

    OpenAIRE

    RAMIRO RICO-MARTINEZ; JOSE ALBERTO GALLEGOS-INFANTE

    1999-01-01

    The crystallization of fatty acids is very important in industrial applications and biological systems. A comparison between theoretical models and experimental data helps in clarifying mechanistic aspects of these systems. In this contribution, we compare the performance of two models in fitting data from the crystallization of supersaturated solutions of palmitic acid in oleic acid. One of the models was developed by Avrami and the other is based on considering diffusion as limiting (the D-...

  7. Influence of surface modification of SrFe12O19 particles with oleic acid on magnetic microsphere preparation

    Institute of Scientific and Technical Information of China (English)

    Sifang Kong; Peipei Zhang; Xiufang Wen; Pihui Pi; Jiang Cheng; Zhuoru Yang; Jing Hai

    2008-01-01

    Oleic acid was used as surface modification agent to improve the hydrophobicity of magnetic strontium hexaferrite particles. The structure and properties of treated magnetic particles were characterized by scanning electronic microscopy (SEM), Fourier transform infrared spectra (FTIR), powder X-ray diffraction (XRD) and magnetic property measurement system (MPMS). The results show that oleic acid is chemically enwrapped on the surface of SrFe12O19 particles. Magnetic particles modified by oleic acid are highly dispersible and strongly responsive to magnetism but with slight decrease in saturated magnetization. The affinity between magnetic particles and monomers is improved by surface modification, resulting in increased particle incorporation in magnetic polymeric microspheres. The surface modification mechanism of magnetic particles by oleic acid is addressed in this work.

  8. Esterification of Oleic Acid for Biodiesel Production Catalyzed by SnCl2: A Kinetic Investigation

    Directory of Open Access Journals (Sweden)

    Marcio J. da Silva

    2008-09-01

    Full Text Available The production of biodiesel from low-cost raw materials which generally contain high amounts of free fatty acids (FFAs is a valuable alternative that would make their production costs more competitive than petroleum-derived fuel. Currently, the production of biodiesel from this kind of raw materials comprises a two-stage process, which requires an initial acid-catalyzed esterification of the FFA, followed by a basecatalyzed transesterification of the triglycerides. Commonly, the acid H2SO4 is the catalyst on the first step of this process. It must be said, however, that major drawbacks such as substantial reactor corrosion and the great generation of wastes, including the salts formed due to neutralization of the mineral acid, are negative and virtually unsurmountable aspects of this protocol. In this paper, tin(II chloride dihydrate (SnCl2·2H2O, an inexpensive Lewis acid, was evaluated as catalyst on the ethanolysis of oleic acid, which is the major component of several fat and vegetable oils feedstocks. Tin chloride efficiently promoted the conversion of oleic acid into ethyl oleate in ethanol solution and in soybean oil samples, under mild reaction conditions. The SnCl2 catalyst was shown to be as active as the mineral acid H2SO4. Its use has relevant advantages in comparison to mineral acids catalysts, such as less corrosion of the reactors and as well as avoiding the unnecessary neutralization of products. Herein, the effect of the principal parameters of reaction on the yield and rate of ethyl oleate production has been investigated. Kinetic measurements revealed that the esterification of oleic acid catalyzed by SnCl2·2H2O is first-order in relation to both FFAs and catalyst concentration. Experimentally, it was verified that the energy of activation of the esterification reaction of oleic acid catalyzed by SnCl2 was very close those reported for H2SO4.

  9. Enhancement of skin permeation of ibuprofen from ointments and gels by sesame oil, sunflower oil and oleic acid

    OpenAIRE

    Dinda S; Vijay Ratna J

    2006-01-01

    Several batches of paraffin ointments were prepared and ibuprofen was incorporated into them. Sesame oil, sunflower oil, and oleic acid in different concentrations were incorporated into different batches. Commercial ibuprofen gel was obtained and divided into several batches and different concentrations of sesame oil, sunflower oil, and oleic acid were incorporated into them. The in vitro drug release characteristics through hairless (88 mm) rat skin was carried out by using modified Inser...

  10. Characterizing Time-Dependent Contact Angles for Sands Hydrophobized with Oleic and Stearic Acids

    DEFF Research Database (Denmark)

    Subedi, Shaphal; Kawamoto, Ken; Jayarathna, Lakmal;

    2012-01-01

    -frequency precipitation. A potential solution is to alter soil grain surfaces to become water repellent by mixing or coating the soil cover material with hydrophobic agents (HAs). In this study, hydrophobic CBs comprised of sands mixed with environmentally friendly HAs (oleic acid [OA] and stearic acid [SA]) were studied....... Water repellency (WR) characteristics for hydrophobized sand samples with different HA contents and representing different coating methods (mixing in and solvent aided) were measured. Initial contact angles (αi) for OA-coated samples sharply increased with increasing HA content and reached peak values...

  11. Effects of oleic acid on the high threshold barium current in seabass Dicentrarchus labrax ventricular myocytes

    OpenAIRE

    Chatelier, Aurelien; Imbert, Nathalie; Zambonino, Jose-luis; McKenzie, David; Bois, P.

    2006-01-01

    The present study employed a patch clamp technique in isolated seabass ventricular myocytes to investigate the hypothesis that oleic acid (OA), a mono-unsaturated fatty acid, can exert direct effects upon whole-cell barium currents. Acute application of free OA caused a dose-dependent depression of the whole-cell barium current that was evoked by a voltage step to 0 mV from a holding potential of -80 mV. The derived 50% inhibitory concentration (IC50) was 12.49 +/- 0.27 mu mol l(-1). At a con...

  12. V2O5-Poly aniline Nano composite as Catalyst in Ozonization of Oleic Acid

    International Nuclear Information System (INIS)

    In this work, the synthesis of Azelaic acid (AA) from oleic acid cleavage is studied. The reaction is done by using V2O5- Poly aniline (pani) nano composite as catalyst in solvent free medium. Preparation of V2O5- pani nano composite as a catalyst is done via micelle solution by using cationic surfactant, cethyl trimethyl ammonium bromide (CTAB). Various loading percentages of V2O5 in Pani are considered and their differences in activity and selectivity are also evaluated. According to GC analysis, results showed that nano composite as catalyst is two times more selective to azelaic acid compare to bulk and nano V2O5. This nano composite has significant selectivity to azelaic acid rather than pelargonic acid , the by-product of oleic acid ozonolysis. For characterization TEM, FESEM, BET, XPS, TGA, XRD analysis are done .It is found that both yield and selectivity are increased when surface area, defects and specific active sites of catalyst are increased. (author)

  13. Development and validation of a GC-FID method for quantitative analysis of oleic acid and related fatty acids☆

    Institute of Scientific and Technical Information of China (English)

    Honggen Zhang; Zhenyu Wang; Oscar Liu

    2015-01-01

    Oleic acid is a common pharmaceutical excipient that has been widely used in various dosage forms. Gas chromatography (GC) has often been used as the quantitation method for fatty acids normally requiring a derivatization step. The aim of this study was to develop a simple, robust, and derivatization-free GC method that is suitable for routine analysis of all the major components in oleic acid USP-NF (United States Pharmacopeia-National Formulary) material. A gas chromatography-flame ionization detection (GC-FID) method was developed for direct quantitative analysis of oleic acid and related fatty acids in oleic acid USP-NF material. Fifteen fatty acids were separated using a DB-FFAP (nitroterephthalic acid modified polyethylene glycol) capillary GC column (30 m × 0.32 mm i.d.) with a total run time of 20 min. The method was validated in terms of specificity, linearity, precision, accuracy, sensitivity, and robustness. The method can be routinely used for the purpose of oleic acid USP-NF material analysis.

  14. EFFECTS OF CRC SIMULACRUM MADE OF OLEIC ACID AND GLYCERIDE ON WET-END AND PAPER PROPERTIES OF NEWSPRONT

    Institute of Scientific and Technical Information of China (English)

    Guanglei Zhao; Beihai He; Liying Qian; Huanbin Liu

    2004-01-01

    Mechanical pulps are widely used in the production of newsprint, and resin is the main component of wood extractives in the pulp, which is harmful to both the wet-end and paper quality especially in newsprint paper mill. In the case of mill whitewater closure, the problems become more noticeable. In this work, the CRC (colloid resin component)simulacrum was made by individually dispersing the oleic acid and glyceride with mechanical method,and the effects on wet-end chemical characteristics and newsprint physical proprieties were discussed. It was found that some of the wet-end characteristics such as cationic demand, Zeta potential, and first pass retention were remarkably affected by the CRC simulacrum. The first pass retention decreased from 75.7% to 69.2% in the presence of oleic glyceride and from 81.7% to 78.4% in the presence of oleic acid in PEO/PFR retention system and from 78.6% to 75.4% (with oleic glyceride) and 74.3%to 70.1% (with oleic acid) in PEI/CPAM retention system. The CRC simulacrum of oleic acid and glyceride remarkably decrease the tensile strength and tear strength of newsprint hand sheets. The scattering coefficient of the hand sheets increased with the concentration of simulacrum.

  15. Phase behavior and properties of salt-free cationic/anionic surfactant mixtures of oleic acid and stearic acid

    Institute of Scientific and Technical Information of China (English)

    ZHAO DianYing; LI HongGuang; SONG AiXin; HAO JingCheng

    2009-01-01

    Cationic base surfactant,tetradecyltrimethylammonium hydroxide (TTAOH),can be obtained through anion exchange from tetradecyltrimethylammonium bromide (TTABr).Salt-free cationic and anionic (catanionic) surfactant mixtures were studied by mixing TTAOH with oleic acid (OA) or stearic acid (SA) in water.The phase behavior of TTAOH/OA/H_2O is compared with that of TTAOH/SA/H_2O.It was found that the phase behavior of TTAOH/OA/H_2O and TTAOH/SA/H_2O system differs from each other due to the existence of the unsaturated double carbon bond (C=C) in OA.At fixed total surfactant concentration (25 mg/mL) of TTAOHIONH_2O system at 25℃,one can observe an isotropic L_1 phase,and a L_1/L_α two-phase region with increasing OA content.The volume of top turbid L.phase increases while the bottom phase changes gradually from transparently clear to a bit turbid until a single L_α-phase is reached.Finally at high OA concentration,excess OA is separated from the bulk aqueous solutions.TTAOH/SA/H_2O system usually forms white precipitating at 25℃ due to the high chain melting temperature of SA.When heated to 60℃,however,the state of samples changes.At fixed total surfactant concentration of 25 mg/mL,an isotropic L1 phase and a milk-white or bluish La-phase are observed with increasing SA concentration.Transparent thin layers which are strongly birefringent form at the tops of some samples within the L_α-phase region.Finally,at high SA concentration,excess SA is separated from the bulk aqueous solutions.In addition to phase behavior study,we also measured the conductivity of TTAOH/OA/H_2O system at 25℃ and TTAOH/SA/H_2O system at 60℃,respectively.Surface tension and rheological measurements were also performed on typical samples.

  16. Characterization of biodegradable film based on zein and oleic acid added with nanocarbonate

    Directory of Open Access Journals (Sweden)

    Wanessa Ximenes Ribeiro

    2015-10-01

    Full Text Available Zein oleic acid films added with 1, 2 and 3 % (w/w of nanocarbonate and 30 % glycerol as plasticizer, were produced and evaluated according to their structure and functional properties. Structural characteristics were analyzed by optical and scanning electron microscopy (SEM. Water solubility and mechanical properties were determined according to ASTM methods. The increase of nanocarbonate concentration increased water solubility and influenced the color and mechanical properties. Optical and SEM of film samples added with nanocarbonate, shown low amount of pores and great fat globules size.

  17. Computational multiple steady states for enzymatic esterification of ethanol and oleic acid in an isothermal CSTR.

    Science.gov (United States)

    Ho, Pang-Yen; Chuang, Guo-Syong; Chao, An-Chong; Li, Hsing-Ya

    2005-05-01

    The capacity of complex biochemical reaction networks (consisting of 11 coupled non-linear ordinary differential equations) to show multiple steady states, was investigated. The system involved esterification of ethanol and oleic acid by lipase in an isothermal continuous stirred tank reactor (CSTR). The Deficiency One Algorithm and the Subnetwork Analysis were applied to determine the steady state multiplicity. A set of rate constants and two corresponding steady states are computed. The phenomena of bistability, hysteresis and bifurcation are discussed. Moreover, the capacity of steady state multiplicity is extended to the family of the studied reaction networks.

  18. Synthesis of CdSe quantum dots via paraffin liquid and oleic acid

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper reported an efficient and rapid method to produce highly monodispersed CdSe quantum dots (QDs), in which the traditional tri10ylphosphine oxide (TOPO) was replaced by paraffin liquid as solvent and oleic acid as the reacting media. The experimental conditions and the properties of QDs had been studied in detail. The resulting samples were confirmed of uniform size distribution with transmission electronic microscopy (TEM), while UV-vis absorption and photoluminescence (PL) spectra clearly indicated that such synthesized QDs had good fluorescence properties.

  19. Optimization of esterification of oleic acid and trimethylolpropane (TMP) and pentaerythritol (PE)

    Science.gov (United States)

    Mahmud, Hamizah Ammarah; Salimon, Jumat

    2014-09-01

    Vegetable oil (VO) is the most potential alternative to replace mineral oil for lubricant due to better lubricating properties and great physicochemical properties. Chemical modification has to be done to overcome low temperature performance and low oxidation instability due to the presence of β-hydrogen atoms of glycerol molecule. The optimization of esterification of oleic acid and polyhydric alcohol with sulfuric acid catalyst was carried out to find the optimum conditions with the highest yield. Reeaction variables such as; molar ratio, temperature, duration and catalyst concentration. Two types of polyhydric alcohol have been used; TMP and PE. The optimum results showed oleic acid successfully converted 91.2% ester TMP and 92.7% ester PE at duration: 5 hours (Ester TMP), 6 hours (Ester PE); temperature: 150°C (ester TMP), 180°C (Ester PE); catalyst concentration: 1.5% (w/w); and mol ratio: 3.9:1 (ester TMP), 4.9:1 (ester PE). From the data obtained, mole ratio showed most influenced factors to the increasing yields of ester conversions.. The TMP/PE ester was confirmed using gas chromatography (GC-FID), Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR).

  20. Optimization of esterification of oleic acid and trimethylolpropane (TMP) and pentaerythritol (PE)

    Energy Technology Data Exchange (ETDEWEB)

    Mahmud, Hamizah Ammarah; Salimon, Jumat [School of Chemical Sciences and Food Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan (Malaysia)

    2014-09-03

    Vegetable oil (VO) is the most potential alternative to replace mineral oil for lubricant due to better lubricating properties and great physicochemical properties. Chemical modification has to be done to overcome low temperature performance and low oxidation instability due to the presence of β-hydrogen atoms of glycerol molecule. The optimization of esterification of oleic acid and polyhydric alcohol with sulfuric acid catalyst was carried out to find the optimum conditions with the highest yield. Reeaction variables such as; molar ratio, temperature, duration and catalyst concentration. Two types of polyhydric alcohol have been used; TMP and PE. The optimum results showed oleic acid successfully converted 91.2% ester TMP and 92.7% ester PE at duration: 5 hours (Ester TMP), 6 hours (Ester PE); temperature: 150°C (ester TMP), 180°C (Ester PE); catalyst concentration: 1.5% (w/w); and mol ratio: 3.9:1 (ester TMP), 4.9:1 (ester PE). From the data obtained, mole ratio showed most influenced factors to the increasing yields of ester conversions.. The TMP/PE ester was confirmed using gas chromatography (GC-FID), Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR)

  1. The oleic acid esterification of policosanol increases its bioavailability and hypocholesterolemic action in rats

    Energy Technology Data Exchange (ETDEWEB)

    Hain, D.; Valenzuela, A.; Branes, M. C.; Fuenzalida, M.; Videla, L. A.

    2012-07-01

    Policosanol comprises a mixture of long-chain aliphatic alcohols from sugarcane wax. More than 50 studies indicate that policosanol decreases serum cholesterol, while others failed to reproduce this effect. The objective of this investigation was to assess the bioavailability of esterified policosanol and non-esterified policosanol (NEP), in relation to their hypocholesterolemic effects. Sprague Dawley rats were given a daily oral dose of 100 mg/kg of NEP, 117 mg kg1 of butyric acid esterified policosanol (BAEP), or 164 mg kg1 of oleic acid esterified policosanol (OAEP). Policosanol absorption was evaluated in plasma between 0 and 3 hours after ingestion. To assess changes in total cholesterol, LDL-cholesterol, HDLcholesterol and triacylglycerols in plasma and liver 3-hydroxy- 3-methylglutaryl coenzyme A reductase (HMG- CoA red) phosphorylation, the rats were supplemented with nonesterified or esterified policosanol for 5 weeks. The results indicate that policosanol absorption was significantly greater in OAEP-treated rats than in those subjected to NEP or BAEP administration. OAEP significantly reduced plasma total and LDL-cholesterol in rats, in addition to a 5.6-fold increase (P < 0.05) in the hepatic content of phosphorylated HMG-CoA red over the control values. In conclusion, esterification of policosanol with oleic acid enhances policosanol bioavailability, and significantly improves the serum lipid profile in normocholesterolemic rats in association with the inactivation of HMG-CoA red controlling cholesterogenesis. (Author) 49 refs.

  2. Aqueous extraction of oleic sunflower oil from whole plant by twin-screw extruder: feasibility study, influence of screw configuration and operating conditions

    OpenAIRE

    Evon, Philippe; Vandenbossche, Virginie; Pontalier, Pierre-Yves; Rigal, Luc

    2007-01-01

    Aqueous extraction process using water alone as medium is an alternative to the solvent oil extraction process from oilseeds. It enables simultaneous recovery of oil and protein. The implementation of a co-rotating twin-screw extruder allows the aqueous extraction of oleic sunflower oil from whole plant. Screw configuration, screw rotation speed and whole plant input flow rate affect directly the efficiency of liquid/solid separation. Wringing out the mixing is possible because of the natu...

  3. Enzymatic reaction of ethanol and oleic acid by lipase and lignin peroxidase in rhamnolipid (RL) reversed micelles

    Institute of Scientific and Technical Information of China (English)

    包珊; 吴秀莲; 武海鹏; 袁兴中; 王侯; 彭馨; 刘欢; 曾光明; 马玉洁; 崔凯龙

    2015-01-01

    An environment friendly bio-surfactant of rhamnolipid (RL) was used as a solvent. The enzymatic reaction of oleic acid catalyzed by lipase and lignin peroxidase (lip) was evaluated. The optimum conditions of enzymatic reaction catalyzed by lipase (lip) were water to amphiphile molar ratio of 30 (20), RL of 60 (60) critical micelle concentration (CMC), pH of 7.0 (3.0) and temperature of 40 (30) °C, respectively. The change of enzyme conformation indicates that, for catalytic of lipase, water content is the most important factor of the enzymatic reaction of oleic acid, and pH for lip. With individual optimum conditions, the enzymatic efficiency of oleic acid catalyzed by lipase is higher than that by lip. In the presence of ethanol, the enzymatic reaction of oleic acid catalyzed by lipase suits Ping-Pong Bi-Bi mechanism. As an alternative to chemical reversed micelles, the RL reversed micelles are promising methods to enzymatic reaction of oleic acid.

  4. Water dispersible oleic acid-coated Fe3O4 nanoparticles for biomedical applications

    International Nuclear Information System (INIS)

    Fe3O4 magnetic nanoparticles (MNPs) have proved their tremendous potential to be used for various biomedical applications. Oleic acid (OA) is widely used in ferrite nanoparticle synthesis because it can form a dense protective monolayer, thereby producing highly uniform and monodispersed particles. Capping agents such as oleic acid are often used because they form a protective monolayer, which is strongly bonded to the surface of nanoparticles. This is necessary for making monodisperse and highly uniform MNPs. Coating of Fe3O4 MNPs with OA makes the particles dispersible only in organic solvents and consequently limits their use for biomedical applications. Hence, in this work, the OA coated MNPs were again functionalized with chitosan (CS), in order to impart hydrophilicity on their surface. All the morphological, magnetic, colloidal and cytotoxic characteristics of the resulting core–shells were studied thoroughly. Their heating induction ability was studied to predict their possible use in hyperthermia therapy of cancer. Specific absorption rate was found to be increased than that of bare MNPs. - Highlights: • Fe3O4 nanoparticles synthesized FeCl2 as the sole source by alkaline precipitation. • Hydrophilicity imparted to OA-Fe3O4 MNPs. • Improved heating induction ability. • Highly stabilized colloidal suspension. • Improved biocompatiblity

  5. Pronounced multiferroicity in oleic acid stabilized BiFeO3 nanocrystals at room temperature.

    Science.gov (United States)

    Mahesh, Dabbugalla; Mandal, Swapan K; Mahato, Bipul K; Rana, Bivas; Barman, Anjan

    2013-06-01

    We report on the experimental observation of pronounced multiferroicity in BiFeO3 nanocrystals (size approximately 40 nm) at room temperature. Large scale BiFeO3 nanocrystals are synthesized using a low temperature chemical route and further stabilized with oleic acid. The nanocrystals exhibit a significant distortion in lattice parameter c compared to the bulk. Oleic acid plays an important role in reducing oxygen vacancies and Fe2+ ions at the nanocrystal surface giving rise to a high resistivity (approximately 10(10) omega-cm at 300 K) of the sample. The direct band gap of nanocrystals is measured to be approximately 4.2 eV (about 1.5 times the bulk value) suggesting a strong quantum confinement effect. The nanocrystals show a remarkably high spontaneous saturation magnetization approximately 4.39 emu/g along with a prominent ferroelectric hysteresis loop at room temperature. Particle size effect leading to the appearance of large number of uncompensated spins and suppression of modulated spin structure have resulted a strong spontaneous magnetization in such nanoscale multiferroic materials. PMID:23862453

  6. Water dispersible oleic acid-coated Fe3O4 nanoparticles for biomedical applications

    Science.gov (United States)

    Shete, P. B.; Patil, R. M.; Tiwale, B. M.; Pawar, S. H.

    2015-03-01

    Fe3O4 magnetic nanoparticles (MNPs) have proved their tremendous potential to be used for various biomedical applications. Oleic acid (OA) is widely used in ferrite nanoparticle synthesis because it can form a dense protective monolayer, thereby producing highly uniform and monodispersed particles. Capping agents such as oleic acid are often used because they form a protective monolayer, which is strongly bonded to the surface of nanoparticles. This is necessary for making monodisperse and highly uniform MNPs. Coating of Fe3O4 MNPs with OA makes the particles dispersible only in organic solvents and consequently limits their use for biomedical applications. Hence, in this work, the OA coated MNPs were again functionalized with chitosan (CS), in order to impart hydrophilicity on their surface. All the morphological, magnetic, colloidal and cytotoxic characteristics of the resulting core-shells were studied thoroughly. Their heating induction ability was studied to predict their possible use in hyperthermia therapy of cancer. Specific absorption rate was found to be increased than that of bare MNPs.

  7. Oleic and Undecylenic Acids as Renewable Feedstocks in the Synthesis of Polyols and Polyurethanes

    Directory of Open Access Journals (Sweden)

    Virginia Cádiz

    2010-10-01

    Full Text Available Nowadays, the utilization of raw materials derived from renewable feedstock is in the spotlight of the chemical industry, as vegetable oils are one of the most important platform chemicals due to their universal availability, inherent biodegradability and low price. Taking into account that polyurethanes are one of the most important industrial products exhibiting versatile properties suitable for use in many fields, our research is focused on exploiting fatty acids in the preparation of biobased polyols and polyurethanes. This review is organized as a function of the nature of the final polyurethane systems; hence we describe the preparation of linear thermoplastic and crosslinked polyurethanes derived from oleic and undecylenic acids-based diols and polyols, respectively.

  8. Effects of low potassium dextran glucose solution on oleic acid-induced acute lung injury in juvenile piglets

    Institute of Scientific and Technical Information of China (English)

    LING Feng; LIU Ying-long; LIU Ai-jun; WANG Dong; WANG Qiang

    2011-01-01

    Background Epithelial dysfunction in lungs plays a key role in the pathogenesis of acute lung injury. The beneficial effects of low potassium dextran glucose solution (LPD) have been reported in lung preservation, and LPD enables injured alveolar pneumocytes to recover. So we hypothesized that systemic administration of LPD may have benefits in treating acute lung injury. We investigated the effects of LPD on arterial blood gas and levels of some cytokines in oleic acid-induced acute lung injury in juvenile piglets.Methods Oleic acid (0.1 ml/kg) was intrapulmonarily administered to healthy anesthetized juvenile piglets. Ten animals were randomly assigned to two groups (n=5 each): oleic acid-induced group (control group) with intravenous infusion of 12.5 ml/kg of lactated Ringer's solution 30 minutes before administration of oleic acid and LPD group with systemic administration of LPD (12.5 ml/kg) 30 minutes before injecting oleic acid. Blood gas variables and concentrations of tumor necrosis factor alpha, endothelin 1 and interleukin 10 were measured before and every 1 hour for 6 hours after initial lung injury.Results Compared with control group, blood pH, partial pressure of arterial oxygen to fraction of inspired oxygen ratio,partial pressure of arterial carbon dioxide, and mean pulmonary arterial pressure in LPD group were improved (P<0.05or 0.01). Six hours after lung injury, concentration of tumor necrosis factor alpha in lung tissue was lower in LPD group than control group (P<0.05). Plasmic concentration of endothelin 1 showed lower in LPD group while plasmic concentration of interleukin 10 showed higher in LPD group (P<0.05).Conclusions Before lung injury, systemic administration of LPD can improve gas exchange, attenuate pulmonary hypertension, decrease plasmic levels of endothelin 1, increase interleukin 10 and decrease concentration of tumor necrosis factor alpha in lung tissue in oleic acid-induced acute lung injury in juvenile piglets.

  9. Phase equilibria of oleic, palmitic, stearic, linoleic and linolenic acids in supercritical CO2

    Directory of Open Access Journals (Sweden)

    P. L. Penedo

    2009-03-01

    Full Text Available The knowledge of the phase equilibrium is one of the most important factors to study the design of separation processes controlled by the equilibrium. Fatty acids are present in high concentration as by-products in vegetable oils but the equilibrium data involving these components is scarce. The objective of this work is the experimental determination of the liquid-vapor equilibrium of five binary different systems formed by carbon dioxide and palmitic acid (C16:0, stearic acid (C18:0, oleic acid (C18:1, linoleic acid (C18:2 and linolenic acid (C18:3. The equilibrium experimental data was collected at 40, 60 and 80ºC at 60, 90 and 120 bar, at the extract and raffinate phases, using an experimental apparatus containing an extractor, a gas cylinder and pressure and temperature controllers. The data was modeled using the cubic equation of state of Peng-Robinson with the mixing rule of van der Waals with binary interaction parameters. The model was adequate to treat the experimental data at each temperature and at all the temperatures together. The best model that includes the van der Waals mixing rule with two parameters has maximum deviation of 17%. The distribution coefficients were also analyzed and it was concluded that the fractionation of the fatty acids is possible using supercritical carbon dioxide.

  10. The kinetics of the solidification of highly supersaturated solutions of palmitic acid in oleic acid: a comparison between two models

    Directory of Open Access Journals (Sweden)

    RAMIRO RICO-MARTINEZ

    1999-08-01

    Full Text Available The crystallization of fatty acids is very important in industrial applications and biological systems. A comparison between theoretical models and experimental data helps in clarifying mechanistic aspects of these systems. In this contribution, we compare the performance of two models in fitting data from the crystallization of supersaturated solutions of palmitic acid in oleic acid. One of the models was developed by Avrami and the other is based on considering diffusion as limiting (the D-model. The D-model fitted the data better than the Avrami model in all cases. The D-model has a low value of the regression coefficient (r2, lower than 0.9 in only three cases. For these points, the thermodynamic force was smaller. Differences in the parameter n (an index of dimensionality were observed; these differences indicate that clusters were present previous to the crystallization process. Furthermore, there appears to be a difference in the mechanism of crystallization of pure solutions of palmitic acid and solutions with a small fraction of oleic acid. Thus, one is lead to the conclusion that the rate of crystallization of fatty acids at high concentrations is limited by diffusion.

  11. Counteracting foaming caused by lipids or proteins in biogas reactors using rapeseed oil or oleic acid as antifoaming agents

    DEFF Research Database (Denmark)

    Kougias, Panagiotis; Boe, Kanokwan; Einarsdottir, E. S.;

    2015-01-01

    deterioration of the methanogenic process. Many commercial antifoams are derivatives of fatty acids or oils. However, it is well known that lipids can induce foaming in manure based biogas plants. This study aimed to elucidate the effect of rapeseed oil and oleic acid on foam reduction and process performance...... carboxylic ends, is responsible for their foam promoting or foam counteracting behaviour. Thus, it was concluded that the fatty acids and oils could suppress foaming, while salt of fatty acids could generate foam....

  12. Oleic Acid Induces Lung Injury in Mice through Activation of the ERK Pathway

    Directory of Open Access Journals (Sweden)

    Cassiano Felippe Gonçalves-de-Albuquerque

    2012-01-01

    Full Text Available Oleic acid (OA can induce acute lung injury in experimental models. In the present work, we used intratracheal OA injection to show augmented oedema formation, cell migration and activation, lipid mediator, and cytokine productions in the bronchoalveolar fluids of Swiss Webster mice. We also demonstrated that OA-induced pulmonary injury is dependent on ERK1/2 activation, since U0126, an inhibitor of ERK1/2 phosphorylation, blocked neutrophil migration, oedema, and lipid body formation as well as IL-6, but not IL-1β production. Using a mice strain carrying a null mutation for the TLR4 receptor, we proved that increased inflammatory parameters after OA challenges were not due to the activation of the TLR4 receptor. With OA being a Na/K-ATPase inhibitor, we suggest the possible involvement of this enzyme as an OA target triggering lung inflammation.

  13. Synthesis of Fe Nanoparticles Functionalized with Oleic Acid Synthesized by Inert Gas Condensation

    Directory of Open Access Journals (Sweden)

    L. G. Silva

    2014-01-01

    Full Text Available In this work, we study the synthesis of monodispersed Fe nanoparticles (Fe-NPs in situ functionalized with oleic acid. The nanoparticles were self-assembled by inert gas condensation (IGC technique by using magnetron-sputtering process. Structural characterization of Fe-NPs was performed by transmission electron microscopy (TEM. Particle size control was carried out through the following parameters: (i condensation zone length, (ii magnetron power, and (iii gas flow (Ar and He. Typically the nanoparticles generated by IGC showed diameters which ranged from ~0.7 to 20 nm. Mass spectroscopy of Fe-NPs in the deposition system allowed the study of in situ nanoparticle formation, through a quadrupole mass filter (QMF that one can use together with a mass filter. When the deposition system works without quadrupole mass filter, the particle diameter distribution is around +/−20%. When the quadrupole is in line, then the distribution can be reduced to around +/−2%.

  14. Investigations of in vitro bioaccessibility from interesterified stearic and oleic acid-rich blends.

    Science.gov (United States)

    Thilakarathna, S H; Rogers, M; Lan, Y; Huynh, S; Marangoni, A G; Robinson, L E; Wright, A J

    2016-04-20

    Interesterification was previously found to impact stearic acid absorption in a randomized cross-over study, when human volunteers consumed a 70 : 30 wt% high-oleic sunflower and canola stearin blend (NIE) compared to the same blend which had undergone either chemical (CIE) or enzymatic (EIE) interesterification. In this research, in vitro lipid digestion, bioaccessibility, and changes in undigested lipid composition and melting behavior of these same test fats were investigated using the dynamic, multi-compartmental TIM-1 digestion model and compared with the previous human study. Overall, TIM-1 bioaccessibility was higher with interesterification (p digestion. TIM-1 bioaccessibility was linearly correlated (R(2) = 0.8640) with postprandial serum TAG concentration in the human study. Therefore, the in vitro digestion model offered predictive insights related to the impacts of lipid interesterificaton on absorption. PMID:26961726

  15. Platinum-nickel catalyst: The effect of promoters in cis-oleic acid adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Simonetti, S., E-mail: ssimonet@uns.edu.ar [Universidad Tecnologica Nacional, Facultad Regional Bahia Blanca, 11 de Abril 461, 8000 Bahia Blanca (Argentina); Universidad Nacional del Sur-IFISUR-CONICET, Av. Alem 1253, 8000 Bahia Blanca (Argentina); Martirena, M.; Ulacco, S. [Universidad Tecnologica Nacional, Facultad Regional Bahia Blanca, 11 de Abril 461, 8000 Bahia Blanca (Argentina); Brizuela, G. [Universidad Nacional del Sur-IFISUR-CONICET, Av. Alem 1253, 8000 Bahia Blanca (Argentina)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer C=O adsorption is more favored than C=C adsorption on the PtNi(1 1 1) surface. Black-Right-Pointing-Pointer The adsorption of the olefinic bond is strengthened by K, Mg, Co, B or Pd promoters. Black-Right-Pointing-Pointer The energy of the system and the C=C/surface distances decrease using promoters. Black-Right-Pointing-Pointer The molecule-surface interaction is favored by electron density exchange. Black-Right-Pointing-Pointer Co promoter shows better adsorption properties than K, Mg, B or Pd. - Abstract: The study of the cis-oleic acid adsorption, on clean and promoted (K, Mg, Co, B or Pd) PtNi(1 1 1) surface was performed by quatum chemical calculations. The oleic acid adsorption on PtNi(1 1 1) surface shows a weak molecule-surface interaction. No preferential site for C=C adsorption is computed and only the C=O adsorption is favored on the clean PtNi(1 1 1) surface. The adsorption properties of the PtNi(1 1 1) are improved by promoters. The stability of the system is increased and the C=C/surface distances are reduced when promoters are present. Among the considered promoters, Co has the best performance in terms of system stability. The lowest C p orbital substantially interacts with Pt and Co s, p and d orbitals. The change electron density of metal centers, enhance the C=C adsorption being the Pt-C interaction the more favored. After adsorption, the strength of the C=C, Pt-Pt and Pt-Co bonds decrease while a molecule-surface bond is formed.

  16. In vitro release and antibacterial activity of poly(oleic/linoleic acid dimer:sebacic acid)-gentamicin

    Institute of Scientific and Technical Information of China (English)

    YANGXiu-Fen; ZHOUZhi-Bin; 等

    2003-01-01

    AIM:To investigate whether poly(oleic/linoleic acid dimer:sebacic acid)-getamicin[Poly(OAD/LOAD:SA)-gentamicin]delivery system was useful to treat chronic osteomyelitis.METHODS:Drug delivery system consisted of gentamicin sufate dispersed in a copolymer containing oleic/linoleic acid dimer(OAD/LOAD)and sebacic acid(SA)in a 1:1 weight ration.The gentamicin releast from[Poly(OAD/LOAD:SA)-gentamicin]was tested in water 0.9% saline,and phosphate buffer 0.1mol/L,RESULTS:The gentamicin concentration peak was found on d2,then slowly decreased.considerable amout of gentamicin was still released on d 50.From d 2 o d 50,the gentamicin concentration in the releasing fluids was from 59 to 42128-fold and 1.8 to 1314-fold of the MIC for Staphylococcus aureus and Escherichia coli,respectively.Staphylococcus aureus and Escherichia coli were strongly inhibited by the releasing fluids for 50d.The gentamicin release and anti-bacterial activity in the three media were similar.only in 0.1mol/L phosphate buffer,from d 2 to 14 it was lower.CONCLUSION:Poly(OAD/LOAD:SA)-gentamicin was useful to treat chronic osteomyelitis.

  17. Proliferation and metabolic significance of peroxisomes in Candida boidinii during growth on D-alanine or oleic acid as the sole carbon source

    NARCIS (Netherlands)

    Sulter, G.J.; Waterham, H.R.; Goodman, J.M.; Veenhuis, M.

    1990-01-01

    We have studied the induction of peroxisomes in the methylotrophic yeast Candida boidinii by D-alanine and oleic acid. The organism was able to utilize each of these compounds as the sole carbon source and grew with growth rates of µ = 0.20 h-1 (on D-alanine) or µ = 0.43 h-1 (on oleic acid). Growth

  18. Enzymatic Synthesis of Furfuryl Alcohol Ester with Oleic Acid by Candida antarctica Lipase B and Its Kinetic Study

    Science.gov (United States)

    Sengupta, Avery; Dey, Tanmoy; Ghosh, Mahua; Ghosh, Jaydip; Ghosh, Santinath

    2012-08-01

    This study investigated the successful enzymatic production of furfuryl oleate and its detailed kinetic study by Michaelis-Menten model. Esterification of oleic acid and furfuryl alcohol by Candida antarctica lipase B (Novozym 435 preparation) in a solvent free system was studied in the present work at 1:1 molar ratio of furfuryl alcohol and oleic acid. About 99 % conversion (on the basis of oleic acid) has been achieved within 6 h at 5 % enzyme concentration. Ping-pong bi-bi mechanism (inhibition phenomenon taken into account) was applied to describe the ratios as a complex kinetic model. The kinetic parameters were determined using MATLAB language programme. The two initial rate constants KA and KB respectively were found out by different progress curves plotted with the help of MATLAB language programme. It was concluded from the results that furfuryl alcohol considerably inhibited the enzymatic reaction while oleic acid had negligible inhibitory effect. It was clearly seen that the initial rate was increased with the increase in the furfuryl alcohol concentration until 2 M/L after which there was a drop in the initial rate depicting the inhibitory effect of furfuryl alcohol. Surprisingly, it has been observed that addition of 0.1 mol of product activated the esterification reaction. Finally, the model was found to be statistically fitting well with the experimental data.

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

    Science.gov (United States)

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

  20. Characterization of Time-Dependent Contact Angles for Oleic Acid Mixed Sands with Different Particle Size Fractions

    DEFF Research Database (Denmark)

    Wijewardana, Y. N. S.; Kawamoto, Ken; Komatsu, Toshiko;

    2014-01-01

    A capillary barrier cover system (CBCS) is a low-cost solution for limiting water infiltration into solid waste landfills. Moreover, hydrophobized sublayer sand grains enhance the impermeable properties of the CBCS. In this study, we have assessed water repellency characteristics for oleic acid (OA...

  1. Binary, ternary and quaternary liquid-liquid equilibria in 1-butanol, oleic acid, water and n-heptane mixtures

    NARCIS (Netherlands)

    Winkelman, J. G. M.; Kraai, G. N.; Heeres, H. J.

    2009-01-01

    This work reports on liquid-liquid equilibria in the system 1-butanol, oleic acid, water and n-heptane used for biphasic, lipase catalysed esterifications. The literature was studied on the mutual solubility in binary systems of water and each of the organic components. Experimental results were obt

  2. Oleic acid may be the key contributor in the BAMLET-induced erythrocyte hemolysis and tumoricidal action.

    Directory of Open Access Journals (Sweden)

    Mehboob Hoque

    Full Text Available A chance discovery of the tumoricidal action of a human milk fraction led to the characterization of the active component as oleic acid complex of the α-lactalbumin, which was given the acronym HAMLET. We report in this study that the oleic acid complex of bovine α-lactalbumin (BAMLET is hemolytic to human erythrocytes as well as to those derived from some other mammals. Indirect immunofluorescence analysis suggested binding of BAMLET to erythrocytes prior to induction of hemolysis. Free OA was hemolytic albeit at higher concentrations, while sodium oleate caused hemolysis at far lower concentrations. Amiloride and BaCl2 offered protection against BAMLET-induced hemolysis suggesting the involvement of a cation leak channel in the process. BAMLET coupled to CNBr-activated Sepharose was not only hemolytic but also tumoricidal to Jurkat and MCF-7 cells in culture. The Sepharose-linked preparation was however not toxic to non-cancerous peritoneal macrophages and primary adipocytes. The tumoricidal action was studied using the MTT-assay while apoptosis induction measured by the annexin V-propidium iodide assay. Repeated incubation of the immobilized BAMLET with erythrocytes depleted oleic acid and decreased the hemolytic activity of the complex. Incubation of MCF-7 and Jurkat cells with OA, soluble or immobilized BAMLET resulted in increase in the uptake of Lyso Tracker Red and Nile red by the cells. The data presented support the contention that oleic acid plays the key role, both in BAMLET-induced hemolysis and tumoricidal action.

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

    Science.gov (United States)

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

  4. PPAR agonists reduce steatosis in oleic acid-overloaded HepaRG cells

    International Nuclear Information System (INIS)

    Although non-alcoholic fatty liver disease (NAFLD) is currently the most common form of chronic liver disease there is no pharmacological agent approved for its treatment. Since peroxisome proliferator-activated receptors (PPARs) are closely associated with hepatic lipid metabolism, they seem to play important roles in NAFLD. However, the effects of PPAR agonists on steatosis that is a common pathology associated with NAFLD, remain largely controversial. In this study, the effects of various PPAR agonists, i.e. fenofibrate, bezafibrate, troglitazone, rosiglitazone, muraglitazar and tesaglitazar on oleic acid-induced steatotic HepaRG cells were investigated after a single 24-hour or 2-week repeat treatment. Lipid vesicles stained by Oil-Red O and triglycerides accumulation caused by oleic acid overload, were decreased, by up to 50%, while fatty acid oxidation was induced after 2-week co-treatment with PPAR agonists. The greatest effects on reduction of steatosis were obtained with the dual PPARα/γ agonist muraglitazar. Such improvement of steatosis was associated with up-regulation of genes related to fatty acid oxidation activity and down-regulation of many genes involved in lipogenesis. Moreover, modulation of expression of some nuclear receptor genes, such as FXR, LXRα and CAR, which are potent actors in the control of lipogenesis, was observed and might explain repression of de novo lipogenesis. Conclusion: Altogether, our in vitro data on steatotic HepaRG cells treated with PPAR agonists correlated well with clinical investigations, bringing a proof of concept that drug-induced reversal of steatosis in human can be evaluated in in vitro before conducting long-term and costly in vivo studies in animals and patients. - Highlights: • There is no pharmacological agent approved for the treatment of NAFLD. • This study demonstrates that PPAR agonists can reduce fatty acid-induced steatosis. • Some nuclear receptors appear to be potent actors in the control

  5. PPAR agonists reduce steatosis in oleic acid-overloaded HepaRG cells

    Energy Technology Data Exchange (ETDEWEB)

    Rogue, Alexandra [Inserm UMR 991, 35043 Rennes Cedex (France); Université de Rennes 1, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes Cedex (France); Biologie Servier, Gidy (France); Anthérieu, Sébastien; Vluggens, Aurore [Inserm UMR 991, 35043 Rennes Cedex (France); Université de Rennes 1, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes Cedex (France); Umbdenstock, Thierry [Technologie Servier, Orléans (France); Claude, Nancy [Institut de Recherches Servier, Courbevoie (France); Moureyre-Spire, Catherine de la; Weaver, Richard J. [Biologie Servier, Gidy (France); Guillouzo, André, E-mail: Andre.Guillouzo@univ-rennes1.fr [Inserm UMR 991, 35043 Rennes Cedex (France); Université de Rennes 1, Faculté des Sciences Pharmaceutiques et Biologiques, 35043 Rennes Cedex (France)

    2014-04-01

    Although non-alcoholic fatty liver disease (NAFLD) is currently the most common form of chronic liver disease there is no pharmacological agent approved for its treatment. Since peroxisome proliferator-activated receptors (PPARs) are closely associated with hepatic lipid metabolism, they seem to play important roles in NAFLD. However, the effects of PPAR agonists on steatosis that is a common pathology associated with NAFLD, remain largely controversial. In this study, the effects of various PPAR agonists, i.e. fenofibrate, bezafibrate, troglitazone, rosiglitazone, muraglitazar and tesaglitazar on oleic acid-induced steatotic HepaRG cells were investigated after a single 24-hour or 2-week repeat treatment. Lipid vesicles stained by Oil-Red O and triglycerides accumulation caused by oleic acid overload, were decreased, by up to 50%, while fatty acid oxidation was induced after 2-week co-treatment with PPAR agonists. The greatest effects on reduction of steatosis were obtained with the dual PPARα/γ agonist muraglitazar. Such improvement of steatosis was associated with up-regulation of genes related to fatty acid oxidation activity and down-regulation of many genes involved in lipogenesis. Moreover, modulation of expression of some nuclear receptor genes, such as FXR, LXRα and CAR, which are potent actors in the control of lipogenesis, was observed and might explain repression of de novo lipogenesis. Conclusion: Altogether, our in vitro data on steatotic HepaRG cells treated with PPAR agonists correlated well with clinical investigations, bringing a proof of concept that drug-induced reversal of steatosis in human can be evaluated in in vitro before conducting long-term and costly in vivo studies in animals and patients. - Highlights: • There is no pharmacological agent approved for the treatment of NAFLD. • This study demonstrates that PPAR agonists can reduce fatty acid-induced steatosis. • Some nuclear receptors appear to be potent actors in the control

  6. Role of p53 in the cellular response following oleic acid accumulation in Chang liver cells.

    Science.gov (United States)

    Park, Eun-Jung; Lee, Ah Young; Chang, Seung-Hee; Yu, Kyeong-Nam; Kim, Jae-Ho; Cho, Myung-Haing

    2014-01-01

    Abnormal accumulation of fatty acids triggers the harmful cellular response called lipotoxicity. In this study, we investigated the cellular response following accumulation of oleic acid (OA), a monounsaturated fatty acid, in human Chang liver cells. OA droplets were distributed freely in the cytoplasm and/or degraded within lysosomes. OA exposure increased ATP production and concomitantly dilated mitochondria. At 24h after OA exposure, cell viability decreased slightly and was coupled with a reduction in mitochondrial Ca(2+) concentration, the alteration in cell viability was also associated with the generation of reactive oxygen species and changes in the cell cycle. Moreover, OA treatment increased the expression of autophagy- and apoptotic cell death-related proteins in a dose-dependent manner. Furthermore, we investigated the role of p53, a tumor suppressor protein, in the cellular response elicited by OA accumulation. OA-induced changes in cell viability and ATP production were rescued to control levels when cells were pretreated with pifithrin-alpha (PTA), a p53 inhibitor. By contrast, the expressions of LC3-II and perilipin, proteins required for lipophagy, were down-regulated by PTA pretreatment. Taken together, our results suggest that p53 plays a key role in the cellular response elicited by OA accumulation in Chang liver cells.

  7. Oleic acid induces smooth muscle foam cell formation and enhances atherosclerotic lesion development via CD36

    Directory of Open Access Journals (Sweden)

    Tang Bing

    2011-04-01

    Full Text Available Abstract Background Elevated plasma free fatty acid (FFA levels have been linked to the development of atherosclerosis. However, how FFA causes atherosclerosis has not been determined. Because fatty acid translocase (FAT/CD36 is responsible for the uptake of FFA, we hypothesized that the atherogenic effects of FFA may be mediated via CD36. Results We tested this hypothesis using cultured rat aortic smooth muscle cells (SMCs treated with oleic acid (OA. We found that OA induces lipid accumulation in SMCs in a dose dependent manner. Rat aortic SMCs treated for 48 hours with OA (250 μmol/L became foam cells based on morphological (Oil Red O staining and biochemical (5 times increase in cellular triglyceride criteria. Moreover, specific inhibition of CD36 by sulfo-N-succinimidyl oleate significantly attenuated OA induced lipid accumulation and foam cell formation. To confirm these results in vivo, we used ApoE-deficient mice fed with normal chow (NC, OA diet, NC plus lipolysis inhibitor acipimox or OA plus acipimox. OA-fed mice showed increased plasma FFA levels and enhanced atherosclerotic lesions in the aortic sinus compared to the NC group (both p 5 μm2 vs. OA plus acipimox: 2.60 ± 0.10 ×105 μm2, p p Conclusions These findings suggest that OA induces smooth muscle foam cell formation and enhances atherosclerotic lesions in part though CD36. Furthermore, these findings provide a novel model for the investigation of atherosclerosis.

  8. Participation of oleic acid in the formation of the aortic aneurysm in Marfan syndrome patients.

    Science.gov (United States)

    Soto, María Elena; Iturriaga Hernández, Alejandra Valeria; Guarner Lans, Verónica; Zuñiga-Muñoz, Alejandra; Aranda Fraustro, Alberto; Velázquez Espejel, Rodrigo; Pérez-Torres, Israel

    2016-03-01

    Marfan syndrome (MFS) is associated with progressive aortic dilatation and endothelial dysfunction that lead to early acute dissection and rupture of the aorta and sudden death. Alteration in fatty acid (FA) metabolism can stimulate nitric oxide (NO) overproduction which increases the activity of the inducible form of NO synthase (iNOS) that is involved in endothelial dysfunction. We evaluated the participation of FA in the formation of thoracic aneurysms in MFS and its relation to the iNOS. Oleic acid (OA), iNOS, citrulline, nitrates and nitrites, TGF-β1, TNF-α, monounsaturated FA and NO synthase activity were significantly increased (p<0.05) in tissue from the aortas of MFS. Saturated FA, eNOS and HDL were significantly decreased (p<0.05). Arachidonic acid, delta-9 desaturase tended to increase and histological examination showed an increase in cystic necrosis, elastic fibers and collagen in MFS. The increase in OA contributes to the altered pathway of iNOS, which favors endothelial dysfunction and formation of the aortic aneurysms in MFS. PMID:27163200

  9. Protease Inhibition by Oleic Acid Transfer From Chronic Wound Dressings to Albumin

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, J. V.; Howley, Phyllis; Davis, Rachel M.; Mashchak, Andrew D.; Goheen, Steven C.

    2007-08-01

    High elastase and cathepsin G activities have been observed in chronic wounds. These levels can inhibit healing through degradation of growth factors, cytokines, and extracellular matrix proteins. Oleic acid (18:1) is a non-toxic elastase inhibitor with some potential for redressing the imbalance of elastase activity found in chronic wounds. Cotton wound dressing material was characterized as a transfer carrier for affinity uptake of 18:1 by albumin under conditions mimicking chronic wounds. 18:1-treated cotton was examined for its ability to bind and release the fatty acid in the presence of albumin. The mechanism of 18:1 uptake from cotton and binding by albumin was examined with both intact dressings and cotton fiber-designed chromatography. Raman spectra of the albumin-18:1 complexes under liquid-liquid equilibrium conditions revealed fully saturated albumin-18:1 complexes with a 1:1 weight ratio of albumin:18:1. Cotton chromatography under liquid-solid equilibrium conditions revealed oleic acid transfer from cotton to albumin at 27 mole equivalents of 18:1 per mole albumin. Cotton was contrasted with hydrogel, and hydrocolloid wound dressing for its comparative ability to lower elastase activity. Each dressing material evaluated was found to release 18:1 in the presence of albumin with significant inhibition of elastase activity. The 18:1-formulated wound dressings lowered elastase activity in a dose dependent manner in the order cotton gauze > hydrogel > hydrocolloid. In contrast the cationic serine protease Cathepsin G was inihibited by 18:1 within a narrow range of 18:1-cotton formulations. Four per cent Albumin solutions were most effective in binding cotton bound-18:1. However, 2% albumin was sufficient to transfer quantities of 18:1 necessary to achieve a significant elastase-lowering effect. Formulations with 128 mg 18:1/g cotton gauze had equivalent elastase lowering with 1 - 4% albumin. 18:1 bound to cotton wound dressings may have promise in the

  10. Additive Regulation of Adiponectin Expression by the Mediterranean Diet Olive Oil Components Oleic Acid and Hydroxytyrosol in Human Adipocytes

    OpenAIRE

    Egeria Scoditti; Marika Massaro; Maria Annunziata Carluccio; Mariangela Pellegrino; Martin Wabitsch; Nadia Calabriso; Carlo Storelli; Raffaele De Caterina

    2015-01-01

    Adiponectin, an adipocyte-derived insulin-sensitizing and anti-inflammatory hormone, is suppressed in obesity through mechanisms involving chronic inflammation and oxidative stress. Olive oil consumption is associated with beneficial cardiometabolic actions, with possible contributions from the antioxidant phenol hydroxytyrosol (HT) and the monounsaturated fatty acid oleic acid (OA, 18:1n-9 cis), both possessing anti-inflammatory and vasculo-protective properties. We determined the effects of...

  11. Behaviour of oleic acid-depleted bovine alpha-lactalbumin made LEthal to tumor cells (BAMLET).

    Science.gov (United States)

    Hoque, Mehboob; Gupta, Jyoti; Rabbani, Gulam; Khan, Rizwan Hasan; Saleemuddin, M

    2016-05-24

    Oleic acid (OA) complexes of human alpha-lactalbumin (α-LA) and several other proteins are effective in the killing of a variety of tumor cells. While debate on whether the key component of the complexes is the OA or protein continues, studies probing the mechanism of action of the complexes at the tumor cell surface or in the cell interior assume the action of a molecule in the form of an undissociated complex. Recent evidence however suggests that OA complexes of protein are stripped of bound OA on interaction with artificial or natural membranes before entering the cell. Properties of BAMLET stripped of its OA by exposure to erythrocytes (ET-BAMLET) were investigated in the study. ET-BAMLET resembled α-LA in its inability to induce hemolysis of erythrocytes and behaviour in a gel filtration column. Spectroscopy techniques-fluorescence, far- and near UV CD as well as calorimetry and proteolysis however suggest the molecule to be different both from native α-LA and the apo form. Remarkably, unlike native α-LA and apo-α-LA, ET-BAMLET binds OA and turns hemolytic by simple mixing with the fatty acid around neutral pH. Since BAMLET/HAMLET incubated cells take up large amounts of OA, the study suggests the possibility of ET-BAMLET combining with OA and reforming the complex inside the cells. PMID:27109252

  12. Study of the surface modification with oleic acid of nanosized HfO{sub 2} synthesized by the polymerized complex derived sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Ramos-Gonzalez, R., E-mail: rramos.phd@gmail.com [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna Hermosillo No. 140, Saltillo, Coahuila 25250 (Mexico); Garcia-Cerda, L.A. [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna Hermosillo No. 140, Saltillo, Coahuila 25250 (Mexico); Quevedo-Lopez, M.A. [University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080-3021 (United States)

    2012-06-01

    The synthesis of nanosized hafnium oxide by the polymerized complex derived sol-gel method is reported. The structural and morphological characterization of the HfO{sub 2} was carried out by X-ray diffraction and scanning electron microscopy. The surface of hafnium oxide nanoparticles was modified by capping with oleic acid. The nanoparticle surface area was measured by the gas adsorption technique in order to determine the minimal amount of oleic acid needed to obtain a uniform coverage of the hafnium oxide. The existence of organic layer can be confirmed by Fourier transform spectroscopy, solid state nuclear magnetic resonance spectroscopy, thermal gravimetric analysis and transmission electron microscopy. The FTIR and solid state NMR results reveal that oleic acid is chemisorbed as a carboxylate onto the HfO{sub 2} nanoparticle surface and confirm the formation of a monomolecular layer of oleic acid surrounding the HfO{sub 2}. The cover density of oleic acid on the HfO{sub 2} increases with the amount of oleic acid used to modify the nanoparticles and the surface properties of HfO{sub 2} nanoparticles modified with oleic acid change from hydrophilic to hydrophobic.

  13. Total liquid ventilation reduces oleic acid-induced lung injury in piglets

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; LIU Dong-hai; ZHANG Yan-bo; LIU Ai-jun; FAN Xiang-ming; QIAO Chen-hui; WANG Qiang

    2013-01-01

    Background Pediatric patients are susceptible to lung injury that does not respond to traditional therapies.Total liquid ventilation has been developed as an alternative ventilatory strategy for severe lung injury.The aim of this study is to investigate the effect of total liquid ventilation on oleic acid (OA)-induced lung injury in piglets.Methods Twelve Chinese immature piglets were induced acute lung injury by OA.Twelve piglets were randomly treated with conventional gas ventilation (control group) or total liquid ventilation (study group) for 240 minutes.Samples for blood gas analysis were collected before,and at 60-minute intervals after OA-induced lung injury.The degree of lung injury was quantified by histologic examination.The inflammatory cells and the levels of IL-1β,IL-6,IL-10 and TNF-α in plasma,tissue and bronchoalveolar lavage were analyzed.Results Neutrophil and macrophage counts in bronchoalveolar lavage were significantly decreased in the study group (P<0.05).The total lung injury score was also reduced in the study group (P<0.05).The cconcentrations of IL-1β,IL-6,IL-10and TNF-α in plasma,tissue and bronchoalveolar lavage were significantly reduced in the study group (P<0.05).Conclusions Total liquid ventilation reduces biochemical and histologic OA-induced lung injury in piglets.

  14. Distinctive interactions of oleic acid covered magnetic nanoparticles with saturated and unsaturated phospholipids in Langmuir monolayers.

    Science.gov (United States)

    Matshaya, Thabo J; Lanterna, Anabel E; Granados, Alejandro M; Krause, Rui W M; Maggio, Bruno; Vico, Raquel V

    2014-05-27

    The growing number of innovations in nanomedicine and nanobiotechnology are posing new challenges in understanding the full spectrum of interactions between nanomateriales and biomolecules at nano-biointerfaces. Although considerable achievements have been accomplished by in vivo applications, many issues regarding the molecular nature of these interactions are far from being well-understood. In this work, we evaluate the interaction of hydrophobic magnetic nanoparticles (MNP) covered with a single layer of oleic acid with saturated and unsaturated phospholipids found in biomembranes through the use of Langmuir monolayers. We find distinctive interactions among the MNP with saturated and unsaturated phospholipids that are reflected by both, the compression isotherms and the surface topography of the films. The interaction between MNP and saturated lipids causes a noticeable reduction of the mean molecular area in the interfacial plane, while the interaction with unsaturated lipids promotes area expansion compared to the ideally mixed films. Moreover, when liquid expanded and liquid condensed phases of the phospholipid(s) coexist, the MNP preferably partition to the liquid-expanded phase, thus hindering the coalescence of the condensed domains with increasing surface pressure. In consequence organizational information on long-range order is attained. These results evidence the existence of a sensitive composition-dependent surface regulation given by phospholipid-nanoparticle interactions which enhance the biophysical relevance of understanding nanoparticle surface functionalization in relation to its interactions in biointerfaces constituted by defined types of biomolecules.

  15. Stability of HAMLET--a kinetically trapped alpha-lactalbumin oleic acid complex.

    Science.gov (United States)

    Fast, Jonas; Mossberg, Ann-Kristin; Svanborg, Catharina; Linse, Sara

    2005-02-01

    The stability toward thermal and urea denaturation was measured for HAMLET (human alpha-lactalbumin made lethal to tumor cells) and alpha-lactalbumin, using circular dichroism and fluorescence spectroscopy as well as differential scanning calorimetry. Under all conditions examined, HAMLET appears to have the same or lower stability than alpha-lactalbumin. The largest difference is seen for thermal denaturation of the calcium free (apo) forms, where the temperature at the transition midpoint is 15 degrees C lower for apo HAMLET than for apo alpha-lactalbumin. The difference becomes progressively smaller as the calcium concentration increases. Denaturation of HAMLET was found to be irreversible. Samples of HAMLET that have been renatured after denaturation have lost the specific biological activity toward tumor cells. Three lines of evidence indicate that HAMLET is a kinetic trap: (1) It has lower stability than alpha-lactalbumin, although it is a complex of alpha-lactalbumin and oleic acid; (2) its denaturation is irreversible and HAMLET is lost after denaturation; (3) formation of HAMLET requires a specific conversion protocol.

  16. Oleic acid is a key cytotoxic component of HAMLET-like complexes.

    Science.gov (United States)

    Permyakov, Sergei E; Knyazeva, Ekaterina L; Khasanova, Leysan M; Fadeev, Roman S; Zhadan, Andrei P; Roche-Hakansson, Hazeline; Håkansson, Anders P; Akatov, Vladimir S; Permyakov, Eugene A

    2012-01-01

    HAMLET is a complex of α-lactalbumin (α-LA) with oleic acid (OA) that selectively kills tumor cells and Streptococcus pneumoniae. To assess the contribution of the proteinaceous component to cytotoxicity of HAMLET, OA complexes with proteins structurally and functionally distinct from α-LA were prepared. Similar to HAMLET, the OA complexes with bovine β-lactoglobulin (bLG) and pike parvalbumin (pPA) (bLG-OA-45 and pPA-OA-45, respectively) induced S. pneumoniae D39 cell death. The activation mechanisms of S. pneumoniae death for these complexes were analogous to those for HAMLET, and the cytotoxicity of the complexes increased with OA content in the preparations. The half-maximal inhibitory concentration for HEp-2 cells linearly decreased with rise in OA content in the preparations, and OA concentration in the preparations causing HEp-2 cell death was close to the cytotoxicity of OA alone. Hence, the cytotoxic action of these complexes against HEp-2 cells is induced mostly by OA. Thermal stabilization of bLG upon association with OA implies that cytotoxicity of bLG-OA-45 complex cannot be ascribed to molten globule-like conformation of the protein component. Overall, the proteinaceous component of HAMLET-like complexes studied is not a prerequisite for their activity; the cytotoxicity of these complexes is mostly due to the action of OA.

  17. Doxorubicin hydrochloride-oleic acid conjugate loaded nanostructured lipid carriers for tumor specific drug release.

    Science.gov (United States)

    Zhao, Shuangni; Minh, Le Van; Li, Na; Garamus, Vasil M; Handge, Ulrich A; Liu, Jianwen; Zhang, Rongguang; Willumeit-Römer, Regine; Zou, Aihua

    2016-09-01

    The hydrophilic drug Doxorubicin hydrochloride (DOX) paired with oleic acid (OA) was successfully incorporated into nanostructured lipid carriers (NLCs) by a high-pressure homogenization (HPH) method. Drug nanovehicles with proper physico-chemical characteristics (less than 200nm with narrow size distribution, spherical shape, layered internal organization, and negative electrical charge) were prepared and characterized by dynamic light scattering, zeta potential measurements, transmission electron microscopy, small-angle X-ray scattering and differential scanning calorimetry. The drug loading and entrapment efficiency of DOX-OA/NLCs were 4.09% and 97.80%, respectively. A pH-dependent DOX release from DOX-OA/NLCs, i.e., fast at pH 3.8 and 5.7 and sustained at pH 7.4, was obtained. A cytotoxicity assay showed that DOX-OA/NLCs had comparable cytotoxicity to pure DOX and were favorably taken up by HCT 116 cells. The intracellular distribution of DOX was also studied using a confocal laser scanning microscope. All of these results demonstrated that DOX-OA/NLCs could be a promising drug delivery system with tumor-specific DOX release for cancer treatment. PMID:27137808

  18. Computational study of cis-oleic acid adsorption on Ni(1 1 1) surface

    Energy Technology Data Exchange (ETDEWEB)

    Simonetti, S., E-mail: ssimonet@uns.edu.ar [Departamento de Fisica, IFISUR, Universidad Nacional del Sur-CONICET, Av. Alem 1253, 8000 Bahia Blanca (Argentina); Departamentos de Ciencias Basicas e Ingenieria Mecanica, Universidad Tecnologica Nacional, Facultad Regional Bahia Blanca, 11 de Abril 461, 8000 Bahia Blanca (Argentina); Ulacco, S. [Departamentos de Ciencias Basicas e Ingenieria Mecanica, Universidad Tecnologica Nacional, Facultad Regional Bahia Blanca, 11 de Abril 461, 8000 Bahia Blanca (Argentina); Brizuela, G.; Juan, A. [Departamento de Fisica, IFISUR, Universidad Nacional del Sur-CONICET, Av. Alem 1253, 8000 Bahia Blanca (Argentina)

    2012-05-15

    In the present work, the Atom Superposition and Electron Delocalization method has been applied in order to study the adsorption of cis-oleic acid on Ni(1 1 1) surface. This molecule presents two active functional groups, C=C (in the middle) and -COOH (at one end). Therefore, it is important to explore adsorption on the metal surface through the C=C bond in a geometry parallel to the surface and also in a vertical one with -COOH pointing at Ni atoms. Our results indicate that the parallel geometry is more stable than the vertical one and C=C bond adsorption dominates the process. Energetic results show a strong interaction with the metallic surface. Ni-Ni, C=C, and C-C bonds are weakened upon adsorption because of a bonding interaction between carbons and nickel surface. We found that Ni 5d{sub z}{sup 2} and 5d{sub yz} orbitals play an important role in the bonding between C p{sub x}, p{sub z} orbitals and surface, and the same happens with Ni 6p{sub x} and Ni 6p{sub z}. A small Ni-H interaction is also detected.

  19. Enhanced Biodegradability, Lubricity and Corrosiveness of Lubricating Oil by Oleic Acid Diethanolamide Phosphate

    Directory of Open Access Journals (Sweden)

    Fang Jianhua

    2012-09-01

    Full Text Available Impacts of oleic acid diethanolamide phosphate (abbreviated as ODAP as an additive on biodegradability, anti-wear capacity, friction-reducing ability and corrosiveness of an unreadily biodegradable HVI 350 mineral lubricating oil was studied. The biodegradabilities of neat lubricating oil and its formulations with ODAP were evaluated on a biodegradation tester. Furthermore, the anti-wear and friction-reducing abilities and the corrosiveness of neat oil and the formulated oils were determined on a four-ball tribotester and a copper strip corrosion tester, respectively. The results indicated that ODAP markedly enhanced biodegradability as well as anti-wear and friction-reducing abilities of the lubricating oil. On the other hand, excellent color ratings of copper strips for both neat oil and the ODAP-doped oil were obtained in the corrosion tests, demonstrating that the corrosiveness of neat oil and the doped oil was negligible, although the latter seemed to provide slightly better anti-corrosion ability.

  20. Kinetics of enzymatic synthesis of liquid wax ester from oleic acid and oleyl alcohol.

    Science.gov (United States)

    Radzi, Salina Mat; Mohamad, Rosfarizan; Basri, Mahiran; Salleh, Abu Bakar; Ariff, Arbakariya; Rahman, Mohammad Basyaruddin Abdul; Rahman, Raja Noor Zaliha Raja Abdul

    2010-01-01

    The kinetics of wax ester synthesis from oleic acid and oleyl alcohol using immobilized lipase from Candida antartica as catalyst was studied with different types of impeller (Rushton turbine and AL-hydrofoil) to create different mixing conditions in 2l stirred tank reactor. The effects of catalyst concentration, reaction temperature, and impeller tip speed on the synthesis were also evaluated. Rushton turbine impeller exhibited highest conversion rate at lower impeller tip speed as compared to AL-hydrofoil impeller. A second-order reversible kinetic model from single progress curve for the prediction of fractional conversion at given reaction time was proposed and the corresponding kinetic parameter values were calculated by non-linear regression method. The results from the simulation using the proposed model showed satisfactory agreement with the experimental data. Activation energy shows a value of 21.77 Kcal/mol. The thermodynamic parameters of the process, enthalpy and entropy, were 21.15 Kcal/mol and 52.07 cal/mol.K, respectively.

  1. Type 1 diacylglycerol acyltransferases of Brassica napus preferentially incorporate oleic acid into triacylglycerol

    Science.gov (United States)

    Aznar-Moreno, Jose; Denolf, Peter; Van Audenhove, Katrien; De Bodt, Stefanie; Engelen, Steven; Fahy, Deirdre; Wallis, James G.; Browse, John

    2015-01-01

    DGAT1 enzymes (acyl-CoA:diacylglycerol acyltransferase 1, EC 2.3.1.20) catalyse the formation of triacylglycerols (TAGs), the most abundant lipids in vegetable oils. Thorough understanding of the enzymology of oil accumulation is critical to the goal of modifying oilseeds for improved vegetable oil production. Four isoforms of BnDGAT1, the final and rate-limiting step in triacylglycerol synthesis, were characterized from Brassica napus, one of the world’s most important oilseed crops. Transcriptional profiling of developing B. napus seeds indicated two genes, BnDGAT1-1 and BnDGAT1-2, with high expression and two, BnDGAT1-3 and BnDGAT1-4, with low expression. The activities of each BnDGAT1 isozyme were characterized following expression in a strain of yeast deficient in TAG synthesis. TAG from B. napus seeds contain only 10% palmitic acid (16:0) at the sn-3 position, so it was surprising that all four BnDGAT1 isozymes exhibited strong (4- to 7-fold) specificity for 16:0 over oleic acid (18:1) as the acyl-CoA substrate. However, the ratio of 18:1-CoA to 16:0-CoA in B. napus seeds during the peak period of TAG synthesis is 3:1. When substrate selectivity assays were conducted with 18:1-CoA and 16:0-CoA in a 3:1 ratio, the four isozymes incorporated 18:1 in amounts 2- to 5-fold higher than 16:0. This strong sensitivity of the BnDGAT1 isozymes to the relative concentrations of acyl-CoA substrates substantially explains the observed fatty acid composition of B. napus seed oil. Understanding these enzymes that are critical for triacylglycerol synthesis will facilitate genetic and biotechnological manipulations to improve this oilseed crop. PMID:26195728

  2. Modeling of olive oil degradation and oleic acid inhibition during chemostat and batch cultivation of Bacillus thermoleovorans IHI-91.

    Science.gov (United States)

    Becker, P; Märkl, H

    2000-12-20

    Olive oil degradation by the thermophilic lipolytic strain Bacillus thermoleovorans IHI-91 in chemostat and batch culture was modeled to obtain a general understanding of the underlying principles and limitations of the process and to quantify its stoichiometry. Chemostat experiments with olive oil as the sole carbon source were successfully described using the Monod chemostat model extended by terms for maintenance requirements and wall growth. Maintenance requirements and biomass yield coefficients were in the range reported for mesophiles. For a chemostat experiment at D = 0.3 h(-1) the model was validated up to an olive oil feed concentration of about 3.0 g L(-1) above which an inhibitory effect occurred. Further analysis showed that the liberated oleic acid is the main cause for this inhibition. Using steady-state oleic acid concentrations measured in chemostat experiments with olive oil as substrate it was possible to derive a kinetic expression for oleic acid utilization, showing that a concentration of 430 mg L(-1) leads to a complete growth inhibition. Oleic acid accumulation observed during batch fermentations can be predicted using a model involving growth-associated lipase production and olive oil hydrolysis. Simulations confirmed that this accumulation is the cause for the sudden growth cessation occurring in batch fermentations with higher olive oil start concentrations. Further, an oscillatory behavior, as observed in some chemostat experiments, can also be predicted using the latter model. This work clearly demonstrates that thermophilic lipid degradation by Bacillus thermoleovorans IHI-91 is limited by long-chain fatty acid beta-oxidation rather than oil hydrolysis.

  3. Aqueous Photochemistry of Glyoxylic Acid.

    Science.gov (United States)

    Eugene, Alexis J; Xia, Sha-Sha; Guzman, Marcelo I

    2016-06-01

    Aerosols affect climate change, the energy balance of the atmosphere, and public health due to their variable chemical composition, size, and shape. While the formation of secondary organic aerosols (SOA) from gas phase precursors is relatively well understood, studying aqueous chemical reactions contributing to the total SOA budget is the current focus of major attention. Field measurements have revealed that mono-, di-, and oxo-carboxylic acids are abundant species present in SOA and atmospheric waters. This work explores the fate of one of these 2-oxocarboxylic acids, glyoxylic acid, which can photogenerate reactive species under solar irradiation. Additionally, the dark thermal aging of photoproducts is studied by UV-visible and fluorescence spectroscopies to reveal that the optical properties are altered by the glyoxal produced. The optical properties display periodicity in the time domain of the UV-visible spectrum of chromophores with absorption enhancement (thermochromism) or loss (photobleaching) during nighttime and daytime cycles, respectively. During irradiation, excited state glyoxylic acid can undergo α-cleavage or participate in hydrogen abstractions. The use of (13)C nuclear magnetic resonance spectroscopy (NMR) analysis shows that glyoxal is an important intermediate produced during direct photolysis. Glyoxal quickly reaches a quasi-steady state as confirmed by UHPLC-MS analysis of its corresponding (E) and (Z) 2,4-dinitrophenylhydrazones. The homolytic cleavage of glyoxylic acid is proposed as a fundamental step for the production of glyoxal. Both carbon oxides, CO2(g) and CO(g) evolving to the gas-phase, are quantified by FTIR spectroscopy. Finally, formic acid, oxalic acid, and tartaric acid photoproducts are identified by ion chromatography (IC) with conductivity and electrospray (ESI) mass spectrometry (MS) detection and (1)H NMR spectroscopy. A reaction mechanism is proposed based on all experimental observations. PMID:27192089

  4. Mutant alleles of FAD2-1A and FAD2-1B combine to produce soybeans with the high oleic acid seed oil trait

    Directory of Open Access Journals (Sweden)

    Pham Anh-Tung

    2010-09-01

    Full Text Available Abstract Background The alteration of fatty acid profiles in soybean [Glycine max (L. Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of the oil. Commodity soybean oil typically contains 20% oleic acid and the target for high oleic acid soybean oil is approximately 80% of the oil; previous conventional plant breeding research to raise the oleic acid level to just 50-60% of the oil was hindered by the genetic complexity and environmental instability of the trait. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two delta-twelve fatty acid desaturase genes, FAD2-1A and FAD2-1B. Results Three polymorphisms found in the FAD2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean lines, there was one unique amino acid change within a highly conserved region of the protein. The mutant FAD2-1B alleles were associated with an increase in oleic acid levels, although the FAD2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD2-1A mutations were combined with the novel mutant FAD2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. Conclusions We were able to produce conventional soybean lines with 80% oleic acid in the oil in two different ways, each requiring the contribution of only two genes. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in two production environments. The presumed causative sequence polymorphisms in the FAD2-1B alleles were developed into highly efficient molecular markers for tracking the

  5. Enhancement of skin permeation of ibuprofen from ointments and gels by sesame oil, sunflower oil and oleic acid

    Directory of Open Access Journals (Sweden)

    Dinda S

    2006-01-01

    Full Text Available Several batches of paraffin ointments were prepared and ibuprofen was incorporated into them. Sesame oil, sunflower oil, and oleic acid in different concentrations were incorporated into different batches. Commercial ibuprofen gel was obtained and divided into several batches and different concentrations of sesame oil, sunflower oil, and oleic acid were incorporated into them. The in vitro drug release characteristics through hairless (88 mm rat skin was carried out by using modified Insertion cell designed in our laboratory. The cell was placed into a borosil beaker containing 50 ml of pH 7.4 phosphate buffer as the diffusion fluid. The beaker was placed over the magnetic stirrer, which was maintained at 37±0.5° to maintain the temperature of diffusion fluid. The released drug content at predetermined time interval was measured using U-V-double beam spectrophotometer at 272 nm. The drug release was raised with increase in oil concentration.

  6. The interaction of equine lysozyme:oleic acid complexes with lipid membranes suggests a cargo off-loading mechanism

    DEFF Research Database (Denmark)

    Nielsen, Søren Bang; Wilhelm, Kristina; Vad, Brian;

    2010-01-01

    with oleic acids (ELOAs) were shown to possess tinctorial and morphological properties, similar to amyloidal aggregates, and to be cytotoxic. ELOA's interactions with phospholipid membranes appear to be central to its biological action, similar to human alpha-lactalbumin made lethal to tumor cells. Here, we...... describe the interaction of ELOA with phospholipid membranes. Confocal scanning laser microscopy shows that ELOA, but not native EL, accumulates on the surface of giant unilamellar vesicles, without inducing significant membrane permeability. Quartz crystal microbalance with dissipation data indicated...... extent when free oleic acid (OA) was added, but not when free OA was removed from ELOA by prior incubation with bovine serum albumin, emphasizing the role of OA in this process. NMR data indicated an equilibrium between free and bound OA, which shifts towards free OA as ELOA is progressively diluted...

  7. Preparation of robust polyamide microcapsules by interfacial polycondensation of p-phenylenediamine and sebacoyl chloride and plasticization with oleic acid.

    Science.gov (United States)

    Rosa, Natacha; Martins, Gabriela V; Bastos, Margarida M S M; Gois, Joana R; Coelho, Jorge F J; Marques, Juliana; Tavares, Carlos J; Magalhães, Fernão D

    2015-01-01

    Microcapsules produced by interfacial polycondensation of p-phenylenediamine (PPD) and sebacoyl chloride (SC) were studied. The products were characterized in terms of morphology, mean diameter and effectiveness of dodecane encapsulation. The use of Tween 20 as dispersion stabilizer, in comparison with polyvinyl alcohol (PVA), reduced considerably the mean diameter of the microcapsules and originated smoother wall surfaces. When compared to ethylenediamine (EDA), microcapsules produced with PPD monomer were more rigid and brittle, prone to fracture during processing and ineffective retention of the core liquid. The use of diethylenetriamine (DETA) cross-linker in combination with PPD did not decrease capsule fragility. On the other hand, addition of a small fraction of oleic acid to the organic phase remarkably improved wall toughness and lead to successful encapsulation of the core-oil. Oleic acid is believed to act as a plasticizer. Its incorporation in the polymeric wall was demonstrated by FTIR and (1)H-NMR.

  8. Increased cardiac index due to terbutaline treatment aggravates capillary-alveolar macromolecular leakage in oleic acid lung injury in dogs

    OpenAIRE

    Briot, Raphael; Bayat, Sam; Anglade, Daniel; Martiel, Jean-Louis; Grimbert, Francis

    2009-01-01

    Introduction We assessed the in vivo effects of terbutaline, a beta2-agonist assumed to reduce microvascular permeability in acute lung injury. Methods We used a recently developed broncho-alveolar lavage (BAL) technique to repeatedly measure (every 15 min. for 4 hours) the time-course of capillary-alveolar leakage of a macromolecule (fluorescein-labeled dextran) in 19 oleic acid (OA) lung injured dogs. BAL was performed in a closed lung sampling site, using a bronchoscope fitted with an infl...

  9. Binary, ternary and quaternary liquid-liquid equilibria in 1-butanol, oleic acid, water and n-heptane mixtures

    OpenAIRE

    Winkelman, J.G.M.; Kraai, G. N.; Heeres, H. J.

    2009-01-01

    This work reports on liquid-liquid equilibria in the system 1-butanol, oleic acid, water and n-heptane used for biphasic, lipase catalysed esterifications. The literature was studied on the mutual solubility in binary systems of water and each of the organic components. Experimental results were obtained on the composition of the coexisting phases of a series of ternary and quaternary mixtures of the components at 301,308 and 313 K. The data were correlated successfully with the UNIQUAC model...

  10. Monodispersed Hollow SO3H-Functionalized Carbon/Silica as Efficient Solid Acid Catalyst for Esterification of Oleic Acid.

    Science.gov (United States)

    Wang, Yang; Wang, Ding; Tan, Minghui; Jiang, Bo; Zheng, Jingtang; Tsubaki, Noritatsu; Wu, Mingbo

    2015-12-01

    SO3H-functionalized monodispersed hollow carbon/silica spheres (HS/C-SO3H) with primary mesopores were prepared with polystyrene as a template and p-toluenesulfonic acid (TsOH) as a carbon precursor and -SO3H source simultaneously. The physical and chemical properties of HS/C-SO3H were characterized by N2 adsorption, TEM, SEM, XPS, XRD, Raman spectrum, NH3-TPD, element analysis and acid-base titration techniques. As a solid acid catalyst, HS/C-SO3H shows excellent performance in the esterification of oleic acid with methanol, which is a crucial reaction in biodiesel production. The well-defined hollow architecture and enhanced active sites accessibility of HS/C-SO3H guarantee the highest catalytic performance compared with the catalysts prepared by activation of TsOH deposited on the ordered mesoporous silicas SBA-15 and MCM-41. At the optimized conditions, high conversion (96.9%) was achieved and no distinct activity drop was observed after 5 recycles. This synthesis strategy will provide a highly effective solid acid catalyst for green chemical processes. PMID:26588826

  11. Supercritical synthesis and in situ deposition of PbS nanocrystals with oleic acid passivation for quantum dot solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tavakoli, M.M. [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Simchi, A., E-mail: simchi@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Aashuri, H. [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of)

    2015-04-15

    Colloidal quantum dot solar cells have recently attracted significant attention due to their low-processing cost and surging photovoltaic performance. In this paper, a novel, reproducible, and simple solution-based process based on supercritical fluid toluene is presented for in situ growth and deposition PbS nanocrystals with oleic-acid passivation. A lead precursor containing sulfur was mixed with oleic acid in toluene and processed in a supercritical fluid condition at different temperatures of 140, 270 and 330 °C for 20 min. The quantum dots were deposited on a fluorine-doped tin oxide glass substrate inside the supercritical reactor. Transmission electron microscopy, X-ray diffraction, absorption and dynamic light scattering showed that the nanocrystals processed at the supercritical condition (330 °C) are fully crystalline with a narrow size distribution of ∼3 nm with an absorption wavelength of 915 nm (bandgap of 1.3 eV). Fourier transform infrared spectroscopy indicated that the PbS quantum dots are passivated by oleic acid molecules during the growth. Photovoltaic characteristics of Schottky junction solar cells showed an improvement over devices prepared by spin-coating. - Highlights: • Supercritical fluid processing and in situ deposition of PbS QDs are presented. • The prepared nanocrystals are mono-dispersed with an optical bandgap of 1.3 eV. • Photovoltaic performance of the in situ deposited nanocrystals is reported. • An improved PV performance compared to spin coated Schottky solar cells is shown.

  12. Omega-9 Oleic Acid Induces Fatty Acid Oxidation and Decreases Organ Dysfunction and Mortality in Experimental Sepsis

    Science.gov (United States)

    Oliveira, Flora Magno de Jesus; Burth, Patrícia; Bozza, Patrícia Torres; Castro Faria, Mauro Velho; Silva, Adriana Ribeiro; de Castro-Faria-Neto, Hugo Caire

    2016-01-01

    Sepsis is characterized by inflammatory and metabolic alterations, which lead to massive cytokine production, oxidative stress and organ dysfunction. In severe systemic inflammatory response syndrome, plasma non-esterified fatty acids (NEFA) are increased. Several NEFA are deleterious to cells, activate Toll-like receptors and inhibit Na+/K+-ATPase, causing lung injury. A Mediterranean diet rich in olive oil is beneficial. The main component of olive oil is omega-9 oleic acid (OA), a monounsaturated fatty acid (MUFA). We analyzed the effect of OA supplementation on sepsis. OA ameliorated clinical symptoms, increased the survival rate, prevented liver and kidney injury and decreased NEFA plasma levels in mice subjected to cecal ligation and puncture (CLP). OA did not alter food intake and weight gain but diminished reactive oxygen species (ROS) production and NEFA plasma levels. Carnitine palmitoyltransferase IA (CPT1A) mRNA levels were increased, while uncoupling protein 2 (UCP2) liver expression was enhanced in mice treated with OA. OA also inhibited the decrease in 5' AMP-activated protein kinase (AMPK) expression and increased the enzyme expression in the liver of OA-treated mice compared to septic animals. We showed that OA pretreatment decreased NEFA concentration and increased CPT1A and UCP2 and AMPK levels, decreasing ROS production. We suggest that OA has a beneficial role in sepsis by decreasing metabolic dysfunction, supporting the benefits of diets high in monounsaturated fatty acids (MUFA). PMID:27078880

  13. Bovine lactoferrin binds oleic acid to form an anti-tumor complex similar to HAMLET.

    Science.gov (United States)

    Fang, Bing; Zhang, Ming; Tian, Mai; Jiang, Lu; Guo, Hui Yuan; Ren, Fa Zheng

    2014-04-01

    α-Lactalbumin (α-LA) can bind oleic acid (OA) to form HAMLET-like complexes, which exhibited highly selective anti-tumor activity in vitro and in vivo. Considering the structural similarity to α-LA, we conjectured that lactoferrin (LF) could also bind OA to obtain a complex with anti-tumor activity. In this study, LF-OA was prepared and its activity and structural changes were compared with α-LA-OA. The anti-tumor activity was evaluated by methylene blue assay, while the apoptosis mechanism was analyzed using flow cytometry and Western blot. Structural changes of LF-OA were measured by fluorescence spectroscopy and circular dichroism. The interactions of OA with LF and α-LA were evaluated by isothermal titration calorimetry (ITC). LF-OA was obtained by heat-treatment at pH8.0 with LD50 of 4.88, 4.95 and 4.62μM for HepG2, HT29, and MCF-7 cells, respectively, all of which were 10 times higher than those of α-LA-OA. Similar to HAMLET, LF-OA induced apoptosis in tumor cells through both death receptor- and mitochondrial-mediated pathways. Exposure of tryptophan residues and the hydrophobic regions as well as the loss of tertiary structure were observed in LF-OA. Besides these similarities, LF showed different secondary structure changes when compared with α-LA, with a decrease of α-helix and β-turn and an increase of β-sheet and random coil. ITC results showed that there was a higher binding number of OA to LF than to α-LA, while both of the proteins interacted with OA through van der Waals forces and hydrogen bonds. This study provides a theoretical basis for further exploration of protein-OA complexes. PMID:24368211

  14. Bovine lactoferrin binds oleic acid to form an anti-tumor complex similar to HAMLET.

    Science.gov (United States)

    Fang, Bing; Zhang, Ming; Tian, Mai; Jiang, Lu; Guo, Hui Yuan; Ren, Fa Zheng

    2014-04-01

    α-Lactalbumin (α-LA) can bind oleic acid (OA) to form HAMLET-like complexes, which exhibited highly selective anti-tumor activity in vitro and in vivo. Considering the structural similarity to α-LA, we conjectured that lactoferrin (LF) could also bind OA to obtain a complex with anti-tumor activity. In this study, LF-OA was prepared and its activity and structural changes were compared with α-LA-OA. The anti-tumor activity was evaluated by methylene blue assay, while the apoptosis mechanism was analyzed using flow cytometry and Western blot. Structural changes of LF-OA were measured by fluorescence spectroscopy and circular dichroism. The interactions of OA with LF and α-LA were evaluated by isothermal titration calorimetry (ITC). LF-OA was obtained by heat-treatment at pH8.0 with LD50 of 4.88, 4.95 and 4.62μM for HepG2, HT29, and MCF-7 cells, respectively, all of which were 10 times higher than those of α-LA-OA. Similar to HAMLET, LF-OA induced apoptosis in tumor cells through both death receptor- and mitochondrial-mediated pathways. Exposure of tryptophan residues and the hydrophobic regions as well as the loss of tertiary structure were observed in LF-OA. Besides these similarities, LF showed different secondary structure changes when compared with α-LA, with a decrease of α-helix and β-turn and an increase of β-sheet and random coil. ITC results showed that there was a higher binding number of OA to LF than to α-LA, while both of the proteins interacted with OA through van der Waals forces and hydrogen bonds. This study provides a theoretical basis for further exploration of protein-OA complexes.

  15. Interaction of antitumor alpha-lactalbumin-oleic acid complexes with artificial and natural membranes.

    Science.gov (United States)

    Zherelova, Olga M; Kataev, Anatoly A; Grishchenko, Valery M; Knyazeva, Ekaterina L; Permyakov, Sergei E; Permyakov, Eugene A

    2009-06-01

    The specific complexes of human alpha-lactalbumin (alpha-LA) with oleic acid (OA), HAMLET and LA-OA-17 (OA-complexes), possess cytotoxic activity against tumor cells but the mechanism of their cell penetration remains unclear. To explore the molecular mechanisms underlying interaction of the OA-complexes with the cell membrane, their interactions with small unilamellar dipalmitoylphosphatidylcholine (DPPC) vesicles and electroexcitable plasma membrane of internodal native and perfused cells of the green alga Chara corallina have been studied. The fractionation (Sephadex G-200) of mixtures of the OA-complexes with the vesicles shows that OA-binding increases the affinity of alpha-LA to DPPC vesicles. Calcium association decreases protein affinity to the vesicles; the effect being less pronounced for LA-OA-17. The voltage clamp technique studies show that LA-OA-17, HAMLET, and their constituents produce different modifying effects on the plasmalemmal ionic channels of the Chara corallina cells. The irreversible binding of OA-complexes to the plasmalemma is accompanied by changes in the activation-inactivation kinetics of developing integral transmembrane currents, suppression of the Ca(2+) current and Ca(2+)-activated Cl(-) current, and by increase in the nonspecific K(+) leakage currents. The latter reflects development of nonselective permeability of the plasma membrane. The HAMLET-induced effects on the plasmalemmal currents are less pronounced and potentiated by LA-OA-17. The control experiments with OA and intact alpha-LA show their qualitatively different and much less pronounced effects on the transmembrane ionic currents. Thus, the modification of alpha-LA by OA results in an increase in the protein association with the model lipid bilayer and in drastic irreversible changes in permeability of several types of the plasmalemmal ionic channels. PMID:19588235

  16. Understanding interactions of oleic acid with basic drugs in solid lipids on different biopharmaceutical levels

    Directory of Open Access Journals (Sweden)

    Zdravka Misic

    2014-06-01

    Full Text Available Recently, the impact of intestinal supersaturation on absorption of poorly water-soluble drugs has raised much interest among researchers. A focus has been mostly to study excipient effects on maintenance of drug supersaturation. The aim of the present study was to better understand the effects of drug-excipient interactions on the level of the anhydrous formulation, upon dispersion in simple buffer media and, in particular, regarding precipitation kinetics. A solid lipid-based formulation comprising PEG-32 stearate and oleic acid (OA (8:2 w/w was developed as a model. Loratadine (pKa = 4.33 and carvedilol (pKa = 8.74 were chosen as basic drugs. UV/FTIR spectroscopy and viscometry were used to characterize drug-OA molecular interactions in solution, while solid formulations were studied using x-ray diffraction, thermal analysis and van’t Hoff solubility-temperature plots. Precipitation kinetics of drug formulations was real-time monitored in phosphate buffer (pH = 6.5 by focused beam reflectance measurements. It was found that the addition of OA in the formulations resulted in substantial drug solubility increase. Although the drug-OA interactions appeared to be partially lost upon formulation dispersion, the extent of precipitation was markedly lowered compared to the formulations without OA. A Precipitation number (Pnc was introduced as a ratio of a relevant residence time of drug in the gastrointestinal tract (GIT to the induction time (the onset time of crystalline precipitation. Without OA, Pnc was already taking critical values (>1, while the anhydrous formulation was still below saturation for both model drugs. Interestingly, the addition of OA resulted in amorphous instead of crystalline precipitates, which is advantageous for drug re-dissolution and absorption. In conclusion, this study provides an improved understanding of OA and basic drug interactions on different levels of in vitro performance for more rational oral formulation

  17. Oleic acid surfactant in polycaprolactone/hydroxyapatite-composites for bone tissue engineering.

    Science.gov (United States)

    Cardoso, Guinea B C; Maniglio, Devid; Volpato, Fabio Z; Tondon, Abhishek; Migliaresi, Claudio; Kaunas, Roland R; Zavaglia, Cecilia A C

    2016-08-01

    Bone substitutes are required to repair osseous defects caused by a number of factors, such as traumas, degenerative diseases, and cancer. Autologous bone grafting is typically used to bridge bone defects, but suffers from chronic pain at the donor-site and limited availability of graft material. Tissue engineering approaches are being investigated as viable alternatives, which ideal scaffold should be biocompatible, biodegradable, and promote cellular interactions and tissue development, need to present proper mechanical and physical properties. In this study, poly(ε-caprolactone) (PCL), oleic acid (OA) and hydroxyapatite (HAp) were used to obtain films whose properties were investigated by contact angle, scanning electron microscopy, atomic force microscopy, tensile mechanical tests, and in vitro tests with U2OS human osteosarcoma cells by direct contact. Our results indicate that by using OA as surfactant/dispersant, it was possible to obtain a homogenous film with HAp. The PCL/OA/Hap sample had twice the roughness of the control (PCL) and a lower contact angle, indicating increased hydrophilicity of the film. Furthermore, mechanical testing showed that the addition of HAp decreased the load at yield point and tensile strength and increased tensile modulus, indicating a more brittle composition vs. PCL matrix. Preliminary cell culture experiments carried out with the films demonstrated that U2OS cells adhered and proliferated on all surfaces. The data demonstrate the improved dispersion of HAp using OA and the important consequences of this addition on the composite, unveiling the potentially of this composition for bone growth support. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1076-1082, 2016. PMID:26033969

  18. Structured triacylglycerol containing behenic and oleic acids suppresses triacylglycerol absorption and prevents obesity in rats

    Directory of Open Access Journals (Sweden)

    Takamatsu Kiyoharu

    2010-07-01

    Full Text Available Abstract Background Dietary 1(3-behenoyl-2,3(1-dioleoyl-rac-glycerol (BOO has been reported to inhibit pancreatic lipase activity in vitro and suppress postprandial hypertriacylglycerolemia in humans. In the present study, the anti-obesity activities of BOO and its inhibitory effects on lymphatic triacylglycerol (TAG absorption were investigated in rats. Methods In Experiment 1, rats were fed either BOO or soybean oil (SO diet for 6 weeks. In the BOO diet, 20% of SO was replaced with an experimental oil rich in BOO. In Experiments 2 and 3, rats cannulated in the thoracic duct were administered an emulsions containing trioleoylglycerol (OOO or an oil mixture (OOO:BOO, 9:1. Tri[1-14C]oleoylglycerol (14C-OOO was added to the emulsions administered in Experiment 3. Results No observable differences were detected in food intake or body weight gain between the BOO and SO groups in Experiment 1. Plasma and liver TAG concentrations and visceral fat weights were significantly lower in the BOO group than in the SO group. The apparent absorption rate of fat was significantly lower in the BOO group than in the SO group. In Experiment 2, the lymphatic recovery of oleic and behenic acids was significantly lower at 5 and 6 h after BOO administration than after OOO administration. In Experiment 3, the lymphatic recovery of 14C-OOO was significantly lower at 5 and 6 h after BOO administration than after OOO administration. Conclusions These results suggest that BOO prevents deposition of visceral fat and hepatic TAG by lowering and delaying intestinal absorption of TAG.

  19. Fatty acid composition, antioxidant and antibacterial properties of the microwave aqueous extract of three varieties of Labisia pumila Benth

    OpenAIRE

    Karimi, Ehsan; Jaafar, Hawa ZE; Ghasemzadeh, Ali; Ebrahimi, Mahdi

    2015-01-01

    Background The present study was conducted in order to evaluate the fatty acid profile, anti-oxidant and anti-bacterial activities from the microwave aqueous extract of the leaves of three different varieties of Labisia pumila Benth. Results The chemical analysis of the extract showed that fatty acids (palmitic, palmitoleic, stearic, oleic, linoleic and α-linolenic) acid as the main components in three varieties of L. pumila leaves. Furthermore, the obtained results of the anti-oxidant reveal...

  20. Effect of oleic-linoleic acid and ?-sitosterol to freezing extender of bulls and stallions semen

    Directory of Open Access Journals (Sweden)

    Érika Saltiva Cruz Bender

    2015-06-01

    Full Text Available Addition of polyunsaturated fatty acids and/or cholesterol to a freezing diluent can modify the sperm plasma membrane composition, influencing its behavior during cryopreservation, thus, favoring seminal cryoresistance. The present study aimed to evaluate the effects of the addition of oleic-linoleic acid, (OLA; ?-sitosterol (?-sit, a plant analog of cholesterol; and OLA + ?-sit in combination to a freezing diluent, on the cryopreservation bull and stallion semen. The following variables were analyzed: motility/vigor, plasma and acrosomal membrane integrity (by Trypan Blue/Giemsa staining, mitochondrial activity (by DAB staining, and lipid peroxidation (by a TBARS assays. The lipids were added according to experimental treatments: C – control group, A1 and A2 – OLA at concentrations of 37 ?M and 74 ?M, B1 and B2 – ?-sit at concentrations of 1 ?g mL-1 and 2 ?g mL-1; AB1 and AB2 – OLA 37 ?M + ?-sit 1 ?g mL-1 and OLA 74 ?M + ?-sit 2 ?g mL-1, respectively. The study was divided into three experiments; in Experiment 1, the concentrations of the groups A1, B1, and AB1 were evaluated, whereas in Experiment 2 the concentrations of the groups A2, B2, and AB2 were analyzed, both experiments were performed with bull semen. We conducted Experiment 3 using equine semen with the addition of lipids at all of the concentrations described. Data were subjected to analysis of variance, using the GLM procedure of SAS, with treatment means compared by Duncan test considering 5% significance. These variables differed significantly after thawing the semen post-collection. However, there was no significant difference between treatments when variables were compared within the same time point, except for Experiment 2, where there was a decrease in motility and vigor decrease post-thaw in the groups following ?-sit addition (C – 51.0 ± 13.7%/2.9 ± 0.4; B2 – 35.8 ± 15.8%/2.3 ± 0.6; AB2 – 38.5 ± 16.6%/2.5 ± 0.5, respectively; p < 0.05. In conclusion, the

  1. Acetic acid extraction from aqueous solutions using fatty acids

    NARCIS (Netherlands)

    IJmker, H.M.; Gramblicka, M.; Kersten, S.R.A.; Ham, van der A.G.J.; Schuur, B.

    2014-01-01

    A major challenge for production of acetic acid via bio-based routes is cost-effective concentration and purification of the acetic acid from the aqueous solutions, for which liquid–liquid extraction is a possible method. A main challenge in extraction of acetic acid from dilute aqueous solutions is

  2. The oleic acid esterification of policosanol increases its bioavailability and hypocholesterolemic action in rats

    Directory of Open Access Journals (Sweden)

    Haim, D.

    2012-10-01

    Full Text Available Policosanol comprises a mixture of long-chain aliphatic alcohols from sugarcane wax. More than 50 studies indicate that policosanol decreases serum cholesterol, while others failed to reproduce this effect. The objective of this investigation was to assess the bioavailability of esterified policosanol and non-esterified policosanol (NEP, in relation to their hypocholesterolemic effects. Sprague Dawley rats were given a daily oral dose of 100 mg/kg of NEP, 117 mg kg–1 of butyric acid esterified policosanol (BAEP, or 164 mg kg–1 of oleic acid esterified policosanol (OAEP. Policosanol absorption was evaluated in plasma between 0 and 3 hours after ingestion. To assess changes in total cholesterol, LDL-cholesterol, HDLcholesterol and triacylglycerols in plasma and liver 3-hydroxy- 3-methylglutaryl coenzyme A reductase (HMG- CoA red phosphorylation, the rats were supplemented with nonesterified or esterified policosanol for 5 weeks. The results indicate that policosanol absorption was significantly greater in OAEP-treated rats than in those subjected to NEP or BAEP administration. OAEP significantly reduced plasma total and LDL-cholesterol in rats, in addition to a 5.6-fold increase (P < 0.05 in the hepatic content of phosphorylated HMG-CoA red over the control values. In conclusion, esterification of policosanol with oleic acid enhances policosanol bioavailability, and significantly improves the serum lipid profile in normocholesterolemic rats in association with the inactivation of HMG-CoA red controlling cholesterogenesis.

    Los Policosanoles están formados por una mezcla de alcoholes alifáticos de cadena larga y se obtienen de las ceras de la caña de azúcar. Más de cincuenta estudios indican que los policosanoles reducen el colesterol sérico, mientras que otros no logran reproducir este efecto. El objetivo de esta investigación fue evaluar la biodisponibilidad de policosanoles esterificados y no esterificados

  3. Self-assembled nanostructures of fully hydrated monoelaidin-elaidic acid and monoelaidin-oleic acid systems.

    Science.gov (United States)

    Yaghmur, Anan; Sartori, Barbara; Rappolt, Michael

    2012-07-01

    In recent years, there has been a surge of interest in exploring the effect of trans-fatty acids (TFAs) on biological membrane properties. The research studies are motivated by an increasing body of evidence suggesting that the consumption of TFAs increases the risk of developing negative health effects such as coronary heart disease and cancer. The ultimate goal of studying the lipid-fatty acid interactions at the molecular level is to predict the biological role of fatty acids in cells. In this regard, it is interesting to elucidate the effect of loading TFAs and their counterpart cis-fatty acids (CFAs) on the physical properties of lipid model membranes. Here, the present study focuses on discussing the following: (1) the effect of mixing monoelaidin (ME, TFA-containing lipid) with its counterpart monoolein (MO, CFA-containing lipid) on modulating the fully hydrated self-assembled structure, and (2) the influence of solubilizing oleic acid (OA) and its trans counterpart elaidic acid (EA) on the fully hydrated ME system. The ME model membrane was selected due to its sensitivity to variations in lipid composition and temperature. Synchrotron small-angle X-ray scattering (SAXS) was applied for studying the temperature-dependent structural behavior of the fully hydrated ME/MO-based system prepared with an equal ME/MO weight ratio and also for characterizing the fully hydrated OA- and EA-loaded ME systems. Wide-angle X-ray (WAXS) experiments were also performed for characterizing the formed crystalline lamellar phases at ambient temperatures. The results demonstrate the significant influence of the partial replacement of ME by MO on the phase behavior. The addition of MO induces the lamellar-nonlamellar phase transitions at ambient temperatures and promotes the formation of the inverted type hexagonal (H(2)) phase above 72 °C. The fully hydrated ME/EA and ME/OA systems with their rich polymorphism exhibit an interesting temperature-dependent complex behavior. The

  4. Changes in liquid clearance of alveolar epithelium after oleic acid-induced acute lung injury in rats

    Institute of Scientific and Technical Information of China (English)

    陶军; 杨天德; 陈祥瑞; 黄河

    2004-01-01

    Objective:Impaired active fluid transport of alveolar epithelium may involve in the pathogenesis and resolution of alveolar edema. Thc objective of this study was to explore the changes in alveolar epithelial liquid clearance during lung edema following acute lung injury induced by oleic acid. Methods:Forty-eight Wistar rats were randomly divided into six groups, I.e. , injured, amiloride, ouabain, amiloride plus ouabain and terbutaline groups. Twenty- four hours after the induction of acute lung injury by intravenous oleic acid (0.25 ml/kg), 5% albumin solution with 1.5 μCi 125Ⅰ-labeled albumin (5 ml/kg) was delivered into both lungs via trachea. Alveolar liquid clearance (ALC), extravascular lung water ( EVLW ) content and arterial blood gases were measured one hour thereafter.Results: At 24 h after the infusion of oleic acid, the rats developed pulmonary edema and severe hypoxemia, with EVLW increased by 47.9% and ALC decreased by 49.2%. Addition of either 2 × 10-3 M amiloride or 5 × 10-4 M ouabain to the instillation further reduced ALC and increased EVLW. ALC increased by approximately 63.7% and EVLW decreased by 46.9% with improved hypoxemia in the Terbutaline (10-4 M) group, compared those in injured rats. A significant negative correlation was found between the increment of EVLW and the reduction of ALC. Onclusions:Active fluid transport of alveolar epithelium might play a role in the pathogenesis of lung edema in acute lung injury.

  5. Dynamic characterization of hydrophobic and hydrophilic solutes in oleic-acid enhanced transdermal delivery using two-photon fluorescence microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Te-Yu; Yang, Chiu-Sheng; Chen, Yang-Fang [Department of Physics, National Taiwan University, Taipei, Taiwan (China); Tsai, Tsung-Hua [Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City, Taiwan (China); Dong, Chen-Yuan, E-mail: cydong@phys.ntu.edu.tw [Department of Physics, National Taiwan University, Taipei, Taiwan (China); Center for Quantum Science and Engineering, National Taiwan University, Taipei, Taiwan (China); Center for Optoelectronic Biomedicine, National Taiwan University, Taipei, Taiwan (China)

    2014-10-20

    In this letter, we propose an efficient methodology of investigating dynamic properties of sulforhodamine B and rhodamine B hexyl ester molecules transporting across ex-vivo human stratum corneum with and without oleic acid enhancement. Three-dimensional, time-lapse fluorescence images of the stratum corneum can be obtained using two-photon fluorescence microscopy. Furthermore, temporal quantifications of transport enhancements in diffusion parameters can be achieved with the use of Fick's second law. Dynamic characterization of solutes transporting across the stratum corneum is an effective method for understanding transient phenomena in transdermal delivery of probe molecules, leading to improved delivery strategies of molecular species for therapeutic purposes.

  6. Optical and structural characterization of oleic acid-stabilized CdTe nanocrystals for solution thin film processing

    OpenAIRE

    Claudio Davet Gutiérrez-Lazos; Mauricio Ortega-López; Pérez-Guzmán, Manuel A; A. Mauricio Espinoza-Rivas; Francisco Solís-Pomar; Rebeca Ortega-Amaya; L. Gerardo Silva-Vidaurri; Virginia C. Castro-Peña; Eduardo Pérez-Tijerina

    2014-01-01

    This work presents results of the optical and structural characterization of oleic acid-stabilized cadmium telluride nanocrystals (CdTe-NC) synthesized by an organometallic route. After being cleaned, the CdTe-NC were dispersed in toluene to obtain an ink-like dispersion, which was drop-cast on glass substrate to deposit a thin film. The CdTe-NC colloidal dispersion as well as the CdTe drop-cast thin films were characterized with regard to the optical and structural properties. TEM analysis i...

  7. Continuous High Rate Anaerobic Treatment of Oleic Acid Based Wastewater is Possible after a Step Feeding Start-Up

    OpenAIRE

    Cavaleiro, A. J.; Salvador, A. F.; Alves, J.I.; Alves, M. M.

    2009-01-01

    Mineralization of a synthetic effluent containing 50% COD as oleic acid was achieved in a continuous anaerobic reactor at organic loading rates up to 21 kg COD m−3 day−1, HRT of 9 h, attaining 99% of COD removal efficiency and a methane yield higher than 70%. A maximum specific methane production rate of 1170 ± 170 mg COD-CH4 g VS−1 day−1 was measured during the reactor’s operation. A start-up strategy combining feeding phases and batch degradation phases was applied to promote the developmen...

  8. Dynamic characterization of hydrophobic and hydrophilic solutes in oleic-acid enhanced transdermal delivery using two-photon fluorescence microscopy

    Science.gov (United States)

    Tseng, Te-Yu; Yang, Chiu-Sheng; Tsai, Tsung-Hua; Chen, Yang-Fang; Dong, Chen-Yuan

    2014-10-01

    In this letter, we propose an efficient methodology of investigating dynamic properties of sulforhodamine B and rhodamine B hexyl ester molecules transporting across ex-vivo human stratum corneum with and without oleic acid enhancement. Three-dimensional, time-lapse fluorescence images of the stratum corneum can be obtained using two-photon fluorescence microscopy. Furthermore, temporal quantifications of transport enhancements in diffusion parameters can be achieved with the use of Fick's second law. Dynamic characterization of solutes transporting across the stratum corneum is an effective method for understanding transient phenomena in transdermal delivery of probe molecules, leading to improved delivery strategies of molecular species for therapeutic purposes.

  9. Improvement of bone formation biomarkers after 1-year consumption with milk fortified with eicosapentaenoic acid, docosahexaenoic acid, oleic acid, and selected vitamins.

    Science.gov (United States)

    Martin-Bautista, Elena; Muñoz-Torres, Manuel; Fonolla, Juristo; Quesada, Miguel; Poyatos, Antonio; Lopez-Huertas, Eduardo

    2010-05-01

    The hypothesis of this study was that the replacement of regular milk with fortified milk in hyperlipidemic adults for 1 year would improve bone biomarkers. The fortified milk contained eicosapentaenoic acid and docosahexaenoic acid from fish oils, oleic acid, vitamins A, B(6), and E, as well as folic acid. We believe that the fortified milk will improve the blood fatty acid profile and vitamin status in subjects to benefit bone health biomarkers. From the 84 patients who accepted to participate, 11 of these were excluded for the presence of metabolic diseases and 1 was excluded for noncompliance with the protocol. Seventy-two hyperlipidemic patients (35-65 years) were randomly divided between 2 study groups. The supplement group (E; n = 39) consumed 0.5 L/d of fortified milk that contained fish oil, oleic acid, and vitamins. The control group (C; n = 33) consumed 0.5 L/d of semiskimmed milk containing the same amount of total fat. Blood samples were taken at T(0), T(3), T(6), and T(12) months to determine plasma fatty acids, vitamins B(6), E, and 25-hydroxyvitamin D and serum folate, calcium, soluble osteoprotegerin (OPG), soluble receptor activator of NF-kappaB ligand (RANKL), osteocalcin, parathormone, type I collagen carboxy-terminal telopeptide, and malondialdehyde. After 1 year, the E group showed a significant increase in plasma eicosapentaenoic acid (42%), docosahexaenoic acid (60%), vitamin B6 (38%), OPG (18%), RANKL (7%), OPG/RANKL (10%), red blood cell folate (21%), serum folate (53%), calcium (4%), vitamin D (11%), and osteocalcin (22%). Dietary supplementation with the fortified milk drink improved nutritional status and bone formation markers in adult hyperlipidemic patients. PMID:20579524

  10. The serum 14C-triolein/3H-oleic acid assimilation test for differential diagnosis of maldigestion and malabsorption

    International Nuclear Information System (INIS)

    In 125 consecutive patients the measurement of serum radioactivities after simultaneous ingestion of 14C-triolein and 3H-oleic acid was investigated as a test of lipid assimilation. The sum of the 2-h and 4-h concentrations of 14C in serum (se(2+4)14C) was most useful as an index of lipid assimilation, and the 2-h serum 3H/14C ratio (se-3H/14C) reflected lipid digestion. Normal values were se(2+4)14C >= 1.0% of the dose ingested per litre serum and se-3H/14C14C correlated significantly with faecal fat (r = -0.56, P 7 g/day. False-negative values appeared mainly in the patients with moderate steatorrhoea and gastrointestinal anastomoses. Only one false-positive se(2+4)14C value was found. Se-3H/14C was abnormal in 24 of the 34 patients with maldigestion with two false-positive results. When the results of se(2+4)14C and se-3H/14C were combined, the predictive value of the test result '' normal lipid assimilation'' was 0.75, that of the test result ''maldigestion'' was 0.93 and that of ''malabsorption'' 0.71. It is concluded that the serum 14C-triolein/3H-oleic acid assimilation test is convenient and inexpensive and may be useful when quantitative faecal collections are not available

  11. Water dispersible oleic acid-coated Fe{sub 3}O{sub 4} nanoparticles for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Shete, P.B.; Patil, R.M.; Tiwale, B.M.; Pawar, S.H., E-mail: pawar_s_h@yahoo.com

    2015-03-01

    Fe{sub 3}O{sub 4} magnetic nanoparticles (MNPs) have proved their tremendous potential to be used for various biomedical applications. Oleic acid (OA) is widely used in ferrite nanoparticle synthesis because it can form a dense protective monolayer, thereby producing highly uniform and monodispersed particles. Capping agents such as oleic acid are often used because they form a protective monolayer, which is strongly bonded to the surface of nanoparticles. This is necessary for making monodisperse and highly uniform MNPs. Coating of Fe{sub 3}O{sub 4} MNPs with OA makes the particles dispersible only in organic solvents and consequently limits their use for biomedical applications. Hence, in this work, the OA coated MNPs were again functionalized with chitosan (CS), in order to impart hydrophilicity on their surface. All the morphological, magnetic, colloidal and cytotoxic characteristics of the resulting core–shells were studied thoroughly. Their heating induction ability was studied to predict their possible use in hyperthermia therapy of cancer. Specific absorption rate was found to be increased than that of bare MNPs. - Highlights: • Fe{sub 3}O{sub 4} nanoparticles synthesized FeCl{sub 2} as the sole source by alkaline precipitation. • Hydrophilicity imparted to OA-Fe{sub 3}O{sub 4} MNPs. • Improved heating induction ability. • Highly stabilized colloidal suspension. • Improved biocompatiblity.

  12. Esterification of oleic acid with methanol by immobilized lipase on wrinkled silica nanoparticles with highly ordered, radially oriented mesochannels.

    Science.gov (United States)

    Pang, Jinli; Zhou, Guowei; Liu, Ruirui; Li, Tianduo

    2016-02-01

    Mesoporous silica nanoparticles with a wrinkled structure (wrinkled silica nanoparticles, WSNs) having highly ordered, radially oriented mesochannels were synthesized by a solvothermal method. The method used a mixture of cyclohexane, ethanol, and water as solvent, tetraethoxysilane (TEOS) as source of inorganic silica, ammonium hydroxide as hydrolysis additive, cetyltrimethylammonium bromide (CTAB) as surfactant, and polyvinylpyrrolidone (PVP) as stabilizing agent of particle growth. Particle size (240nm to 540nm), specific surface areas (490m(2)g(-1) to 634m(2)g(-1)), surface morphology (radial wrinkled structures), and pore structure (radially oriented mesochannels) of WSN samples were varied using different molar ratios of CTAB to PVP. Using synthesized WSN samples with radially oriented mesochannels as support, we prepared immobilized Candida rugosa lipase (CRL) as a new biocatalyst for biodiesel production through the esterification of oleic acid with methanol. These results suggest that WSNs with highly ordered, radially oriented mesochannels have promising applications in biocatalysis, with the highest oleic acid conversion rate of about 86.4% under the optimum conditions. PMID:26652346

  13. Effect of heating at frying temperature on the quality characteristics of regular and high-oleic acid sunflower oils

    Directory of Open Access Journals (Sweden)

    M Abbas Ali

    2013-06-01

    Full Text Available Background.Understanding of oil deterioration during heating/frying process is important as oils are nor- mally kept hot at commercial food outlets during intermittent frying cycles. An increased level of consumer awareness toward fat composition and its impact on human health could have an effect on selection of fats in the food industry. The rate of quality deterioration during heating depends on fatty acid composition and also the content and composition of minor components. Therefore, the use of more stable frying oils would be desirable. The present study compares the heat stability at frying temperature of regular sunflower oil (RSFO with that of high-oleic acid sunflower oil (HSFO.  Material and methods. Heating test was carried out at 185 ±5°C for the samples RSFO and HSFO using electric fryer for 8 h/day for 3 consecutive days. The samples were collected every 4 h. The changes in phys- icochemical properties of the samples were monitored by analytical and instrumental methods.  Results.In this study, refractive index, free fatty acid content, peroxide value, p-anisidine value, TOTOXvalue and polar compounds of the oils all increased, whereas C    /C ratio decreased as heating progressed.The percentage of linoleic acid tended to decrease, whereas the percentages of palmitic, stearic and oleic ac-ids increased. The sample HSFO exhibited better heating performance compared to RSFO. However, a higher amount of free fatty acids was found in HSFO compared to RSFO at the end of heating trial. Moreover, heat- ing process decreased the total tocopherol content and higher reduction was detected in RSFO.  Conclusion.In conclusion, the heating caused the formation of comparatively lower amounts of some deg- radative products in HSFO compared to RSFO indicating a lower extent of quality deterioration of HSFO.    

  14. (13)C NMR characterization of triacylglycerols of Moringa oleifera seed oil: an "oleic-vaccenic acid" oil.

    Science.gov (United States)

    Vlahov, Giovanna; Chepkwony, Paul Kiprono; Ndalut, Paul K

    2002-02-27

    The composition of acyl chains and their positions in the triacylglycerols of the oil extracted from seeds of Moringa oleifera were studied by (13)C NMR spectroscopy. The unsaturated chains of M. oleifera seed oil were found to comprise only mono-unsaturated fatty acids and, in particular, two omega-9 mono-unsaturated acids, (cis-9-octadecenoic (oleic acid) and cis-11-eicosenoic acids) and one omega-7 mono-unsaturated acid (cis-11-octadecenoic acid (vaccenic acid)). The mono-unsaturated fatty acids were detected as separated resonances in the spectral regions where the carbonyl and olefinic carbons resonate according to the 1,3- and 2-positions on the glycerol backbone. The unambiguous detection of vaccenic acid was also achieved through the resonance of the omega-3 carbon. The (13)C NMR methodology enabled the simultaneous detection of oleate, vaccenate, and eicosenoate chains according to their positions on the glycerol backbone (1,3- and 2-positions) through the carboxyl, olefinic, and methylene envelope carbons of the triacylglycerol acyl chains. PMID:11853466

  15. Responses to increasing amounts of high-oleic sunflower fatty acids infused into the abomasum of lactating dairy cows.

    Science.gov (United States)

    Drackley, J K; Overton, T R; Ortiz-Gonzalez, G; Beaulieu, A D; Barbano, D M; Lynch, J M; Perkins, E G

    2007-11-01

    Increasing the oleic acid (18:1 cis-9) content of milk fat might be desirable to meet consumer concerns about dietary healthfulness and for certain manufacturing applications. The extent to which milk fat could be enriched with oleic acid is not known. Increasing the intestinal supply of polyunsaturated fatty acids decreases dry matter intake (DMI) in cows, but the effects of oleic acid have not been quantified. In a crossover design, 4 multiparous Holstein cows were abomasally infused with increasing amounts (0, 250, 500, 750, or 1,000 g/d) of free fatty acids from high-oleic sunflower oil (HOSFA) or with carrier alone. Continuous infusions (20 to 22 h/d) were for 7 d at each amount. Infusions were homogenates of HOSFA with 240 g/d of meat solubles and 11.2 g/d of Tween 80; controls received carrier only. The HOSFA contained (by wt) 2.4% 16:0, 1.8% 18:0, 91.4% 18:1 cis-9, and 2.4% 18:2. The DMI decreased linearly (range 22.0 to 5.8 kg/d) as the infused amount of HOSFA increased. Apparent total tract digestibilities of dry matter, organic matter, neutral detergent fiber, and energy decreased as the infusion increased to 750 g/d and then increased when 1,000 g/d was infused. Digestibility of total fatty acids increased linearly as infused fatty acids increased. Yields of milk, fat, true protein, casein, and total solids decreased quadratically as infused amounts increased; decreases were greatest when 750 or 1,000 g/d of HOSFA were infused. Concentrations of fat and total solids increased at the higher amounts of HOSFA. The volume mean diameter of milk fat droplets and the diameter below which 90% of the volume of milk fat is contained both increased as HOSFA infusion increased. Concentrations of short-chain fatty acids, 12:0, 14:0, and 16:0 in milk fat decreased linearly as HOSFA increased. The concentration of 18:1 cis-9 (19.4 to 57.4% of total fatty acids) increased linearly as HOSFA infusion increased. Concentrations of 18:1 cis-9 in blood triglyceride

  16. Effect of feeding high-oleic-acid peanuts to growing-finishing swine on resulting carcass fatty acid profile and on carcass and meat quality characteristics.

    Science.gov (United States)

    Myer, R O; Johnson, D D; Knauft, D A; Gorbet, D W; Brendemuhl, J H; Walker, W R

    1992-12-01

    A high-oleic-acid peanut breeding line was used in a study designed to determine the effects of feeding swine diets containing elevated levels of monounsaturated fatty acids as a means to increase the level of monounsaturates and total unsaturates in the resulting carcass fat. Forty-eight pigs were allotted to four treatments that consisted of corn-soybean meal diets that contained 1) high-oleic peanuts (HOP), 2) regular commercial peanuts (RP), or 3) canola oil (CO), each added at a dietary level to provide 10% added fat/oil, and 4) a control diet with no added fat/oil. The oil of HOP averaged 75% oleic acid vs 60% for CO and 53% for RP. The pigs were fed the experimental diets from 33 to 102 kg BW, after which all pigs were slaughtered. All three dietary oil sources resulted in increases (P HOP diet resulted in the greatest increase (32% greater than control). Both CO and RP increased (P HOP resulted in a small decrease. Total unsaturates increased (P HOP, RP, and CO treatments, respectively, over that obtained from the control treatment. Carcass fat was softer/oilier (P HOP diets, compared with carcass fat of pigs fed the control diet. Dietary fat/oil source had no effect (P > .05) on other carcass compositional traits and various meat quality attributes.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1474012

  17. Molecular mechanisms of the cytotoxicity of human α-lactalbumin made lethal to tumor cells (HAMLET) and other protein-oleic acid complexes.

    Science.gov (United States)

    Nakamura, Takashi; Aizawa, Tomoyasu; Kariya, Ryusho; Okada, Seiji; Demura, Makoto; Kawano, Keiichi; Makabe, Koki; Kuwajima, Kunihiro

    2013-05-17

    Although HAMLET (human α-lactalbumin made lethal to tumor cells), a complex formed by human α-lactalbumin and oleic acid, has a unique apoptotic activity for the selective killing of tumor cells, the molecular mechanisms of expression of the HAMLET activity are not well understood. Therefore, we studied the molecular properties of HAMLET and its goat counterpart, GAMLET (goat α-lactalbumin made lethal to tumor cells), by pulse field gradient NMR and 920-MHz two-dimensional NMR techniques. We also examined the expression of HAMLET-like activities of complexes between oleic acid and other proteins that form a stable molten globule state. We observed that both HAMLET and GAMLET at pH 7.5 were heterogeneous, composed of the native protein, the monomeric molten globule-like state, and the oligomeric species. At pH 2.0 and 50 °C, HAMLET and GAMLET appeared in the monomeric state, and we identified the oleic acid-binding site in the complexes by two-dimensional NMR. Rather surprisingly, the binding site thus identified was markedly different between HAMLET and GAMLET. Furthermore, canine milk lysozyme, apo-myoglobin, and β2-microglobulin all formed the HAMLET-like complex with the anti-tumor activity, when the protein was treated with oleic acid under conditions in which their molten globule states were stable. From these results, we conclude that the protein portion of HAMLET, GAMLET, and the other HAMLET-like protein-oleic acid complexes is not the origin of their cytotoxicity to tumor cells and that the protein portion of these complexes plays a role in the delivery of cytotoxic oleic acid molecules into tumor cells across the cell membrane.

  18. Growth of catalase A and catalase T deficient mutant strains of Saccharomyces cerevisiae on ethanol and oleic acid: Growth profiles and catalase activities in relation to microbody proliferation

    OpenAIRE

    van der Klei, Ida J.; Rytka, Joanna; Kunau, Wolf H.; Veenhuis, Marten

    1990-01-01

    The parental strain (A+T+) of Saccharomyces cerevisiae and mutants, deficient in catalase T (A+T-), catalase A (A-T+) or both catalases (A-T-), grew on ethanol and oleic acid with comparable doubling times. Specific activities of catalase were low in glucose- and ethanol-grown cells. In the two oleic acid-grown A+-strains (A+T+ and A+T-) high catalase activities were found; catalase activity invariably remained low in the A-T+ strain and was never detected in the A-T- strain. The levels of β-...

  19. Designing hydrophobic sheet protected Eu(III)-tetracycline complex using long chain unsaturated fatty acid: Efficient ‘antenna effect’ in aqueous medium

    Energy Technology Data Exchange (ETDEWEB)

    Samanta, Swarna Kamal; Sanyal, Sagarika; Samanta, Sugata; Ghosh, Sanjib, E-mail: pchemsg@gmail.com

    2015-04-15

    We have designed a novel ternary system consisting of Tetracycline hydrochloride (TC), Eu(III) and unsaturated long chain fatty acid (Oleic acid, α-Linolenic acid) in aqueous buffer at physiological pH of 7.2. The systems exhibit highly efficient ‘antenna effect’ of Eu(III) compared to that observed in the binary system of TC and Eu(III) [Eu{sub 3}TC]. Transients of Eu(III) emission in aqueous buffer and D{sub 2}O buffer show that the number of water molecules, coordinated directly to the Eu(III) ion, decreases from 12 in Eu{sub 3}TC to 2 in the ternary system using oleic acid. The micelle formed by the bent conformation of the unsaturated oleic acid provides a hydrophobic sheet on all sides of Eu{sub 3}TC complex protecting Eu(III) from interacting with O–H oscillator. The simple biocompatible system could be used for imaging purpose, and biomedical assay. - Highlights: • A ternary system containing a ligand, oleic acid and Eu(III) has been developed. • The system exhibits enhanced ‘antenna effect’ in aqueous medium at pH=7.2. • This may help design a useful biosensor/imaging technique using Eu(III)

  20. Designing hydrophobic sheet protected Eu(III)-tetracycline complex using long chain unsaturated fatty acid: Efficient ‘antenna effect’ in aqueous medium

    International Nuclear Information System (INIS)

    We have designed a novel ternary system consisting of Tetracycline hydrochloride (TC), Eu(III) and unsaturated long chain fatty acid (Oleic acid, α-Linolenic acid) in aqueous buffer at physiological pH of 7.2. The systems exhibit highly efficient ‘antenna effect’ of Eu(III) compared to that observed in the binary system of TC and Eu(III) [Eu3TC]. Transients of Eu(III) emission in aqueous buffer and D2O buffer show that the number of water molecules, coordinated directly to the Eu(III) ion, decreases from 12 in Eu3TC to 2 in the ternary system using oleic acid. The micelle formed by the bent conformation of the unsaturated oleic acid provides a hydrophobic sheet on all sides of Eu3TC complex protecting Eu(III) from interacting with O–H oscillator. The simple biocompatible system could be used for imaging purpose, and biomedical assay. - Highlights: • A ternary system containing a ligand, oleic acid and Eu(III) has been developed. • The system exhibits enhanced ‘antenna effect’ in aqueous medium at pH=7.2. • This may help design a useful biosensor/imaging technique using Eu(III)

  1. Oleic acid and glucose regulate glucagon-like peptide 1 receptor expression in a rat pancreatic ductal cell line

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Leshuai W.; McMahon Tobin, Grainne A.; Rouse, Rodney L., E-mail: rodney.rouse@fda.hhs.gov

    2012-10-15

    The glucagon-like peptide 1 receptor (GLP1R) plays a critical role in glucose metabolism and has become an important target for a growing class of drugs designed to treat type 2 diabetes. In vitro studies were designed to investigate the effect of the GLP1R agonist, exenatide (Ex4), in “on-target” RIN-5mF (islet) cells as well as in “off-target” AR42J (acinar) and DSL-6A/C1 (ductal) cells in a diabetic environment. Ex4 increased islet cell proliferation but did not affect acinar cells or ductal cells at relevant concentrations. A high caloric, high fat diet is a risk factor for impaired glucose tolerance and type-2 diabetes. An in vitro Oleic acid (OA) model was used to investigate the effect of Ex4 in a high calorie, high fat environment. At 0.1 and 0.4 mM, OA mildly decreased the proliferation of all pancreatic cell types. Ex4 did not potentiate the inhibitory effect of OA on cell proliferation. Akt phosphorylation in response to Ex4 was diminished in OA-treated ductal cells. GLP1R protein detected by western blot was time and concentration dependently decreased after glucose stimulation in OA-treated ductal cells. In ductal cells, OA treatment altered the intracellular localization of GLP1R and its co-localization with early endosome and recycling endosomes. Chloroquine (lysosomal inhibitor), N-acetyl-L-cysteine (reactive oxygen species scavenger) and wortmannin (a phosphatidylinositol-3-kinase inhibitor), fully or partially, rescued GLP1R protein in OA-pretreated, glucose-stimulated ductal cells. The impact of altered regulation on phenotype/function is presently unknown. However, these data suggest that GLP1R regulation in ductal cells can be altered by a high fat, high calorie environment. -- Highlights: ► Exenatide did not inhibit islet, acinar or ductal cell proliferation. ► GLP1R protein decreased after glucose stimulation in oleic acid-treated ductal cells. ► Oleic acid treatment altered localization of GLP1R with early and recycling

  2. Comparison of Chemical Characteristics of High Oleic Acid Fraction of Moringa oleifera Oil with Some Vegetable Oils

    Directory of Open Access Journals (Sweden)

    F. Rahman1

    2014-06-01

    Full Text Available Chemical characteristics of High oleic acid fraction (HOF of Moringa oleifera oil (MOO was compared with sunflower, soybean and canola oils. HOF of MOO was obtained by dry fractionation at 0oC. Iodine value and C18:1 in HOF increased from 61.55 to 82.47 points and 70.29% to 81.15%, respectively. Cloud point of HOF was 1.1oC as compared to 10.2oC in MOO. The induction period of HOF was greater than all the vegetable oils tested in this investigation. HOF can be used as a source of edible oil with better health attributes and superior storage stability.

  3. Novel Proton Conducting Solid Bio-polymer Electrolytes Based on Carboxymethyl Cellulose Doped with Oleic Acid and Plasticized with Glycerol

    Science.gov (United States)

    Chai, M. N.; Isa, M. I. N.

    2016-01-01

    The plasticized solid bio-polymer electrolytes (SBEs) system has been formed by introducing glycerol (Gly) as the plasticizer into the carboxymethyl cellulose (CMC) doped with oleic acid (OA) via solution casting techniques. The ionic conductivity of the plasticized SBEs has been studied using Electrical Impedance Spectroscopy. The highest conductivity achieved is 1.64 × 10−4 S cm−1 for system containing 40 wt. % of glycerol. FTIR deconvolution technique had shown that the conductivity of CMC-OA-Gly SBEs is primarily influenced by the number density of mobile ions. Transference number measurement has shown that the cation diffusion coefficient and ionic mobility is higher than anion which proved the plasticized polymer system is a proton conductor. PMID:27265642

  4. Novel Proton Conducting Solid Bio-polymer Electrolytes Based on Carboxymethyl Cellulose Doped with Oleic Acid and Plasticized with Glycerol

    Science.gov (United States)

    Chai, M. N.; Isa, M. I. N.

    2016-06-01

    The plasticized solid bio-polymer electrolytes (SBEs) system has been formed by introducing glycerol (Gly) as the plasticizer into the carboxymethyl cellulose (CMC) doped with oleic acid (OA) via solution casting techniques. The ionic conductivity of the plasticized SBEs has been studied using Electrical Impedance Spectroscopy. The highest conductivity achieved is 1.64 × 10‑4 S cm‑1 for system containing 40 wt. % of glycerol. FTIR deconvolution technique had shown that the conductivity of CMC-OA-Gly SBEs is primarily influenced by the number density of mobile ions. Transference number measurement has shown that the cation diffusion coefficient and ionic mobility is higher than anion which proved the plasticized polymer system is a proton conductor.

  5. Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating

    International Nuclear Information System (INIS)

    The post-modified Mn–Zn ferrite was prepared by grafting oleic acid on the surface of Mn–Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz–1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite. - Highlights: • The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on its surface to inhibit aggregation. • The increasing in hydrophobicity and dispersion of modified coating improved compatibility between illers and polymer. • The modified fillers can decrease the friction COF of the composite coatings resulting in the enhanced resistance to wear. • The modified ferrite coatings are observed to exhibit better reflection loss compared with coatings with original ferrite

  6. Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wenjie; Zang, Chongguang, E-mail: zangchongguang@bit.edu.cn; Jiao, Qingjie

    2015-03-15

    The post-modified Mn–Zn ferrite was prepared by grafting oleic acid on the surface of Mn–Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz–1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite. - Highlights: • The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on its surface to inhibit aggregation. • The increasing in hydrophobicity and dispersion of modified coating improved compatibility between illers and polymer. • The modified fillers can decrease the friction COF of the composite coatings resulting in the enhanced resistance to wear. • The modified ferrite coatings are observed to exhibit better reflection loss compared with coatings with original ferrite.

  7. Effects of dietary high-oleic acid sunflower oil, copper and vitamin E levels on the fatty acid composition and the quality of dry cured Parma ham.

    Science.gov (United States)

    Bosi, P; Cacciavillani, J A; Casini, L; Lo Fiego, D P; Marchetti, M; Mattuzzi, S

    2000-02-01

    The effects of seven isoenergetic dietary treatments: (1) no sunflower oil, 35 mg/kg Cu, without α-tocopheryl-acetate added; (2) to (7) 6% high oleic acid sunflower oil (HOSO), 35 or 175 mg/kg Cu crossed with a 0, 100 or 200 mg/kg α-tocopherol addition, were tested on quality characteristics of dry cured Parma hams from a total 84 Large White gilts. No statistically significant effect was detected on parameters of early evaluation of seasoning loss of hams. The seasoning loss and intramuscular fat content of seasoned hams averaged 28.1 and 3.3%, respectively, with no effect of the diet composition. The CIE L*a*b* colour values taken on the surface of the lean from Parma ham were not affected by dietary oil inclusion, nor by copper levels and by α-tocopherol addition in the feed mixture, except for the 'a' value that increased in HOSO groups (Poil group, the Parma hams in the HOSO groups showed a higher oleic acid content in the covering fat, but not different in neutral and polar fractions from semimenbranosus muscle. The oil inclusion reduced the saturated fatty acid content in subcutaneous fat and neutral lipids fraction from muscle to 30-34% No effect of α-tocopherol and copper levels were observed on fatty acids profiles. From the subjects fed the HOSO diet softer Parma hams were produced than those fed the control diet (χ(2)<0.05), while α-tocopherol and Cu levels did not influence the sensorial evaluation of hams. The inclusion of an oleic acid rich source in heavy pig diet brought about an improved nutritional value, but also the possible need of a prolonged ageing time to achieve an ideal firmness of Parma ham. Dietary α-tocopherol supplementation improved the red colour slightly and the lipid stability in Parma ham, while the supplementation of Cu in the diet had no influence on the tested parameters.

  8. Reduced Plasma Nonesterified Fatty Acid Levels and the Advent of an Acute Lung Injury in Mice after Intravenous or Enteral Oleic Acid Administration

    Directory of Open Access Journals (Sweden)

    Cassiano Felippe Gonçalves de Albuquerque

    2012-01-01

    Full Text Available Although exerting valuable functions in living organisms, nonesterified fatty acids (NEFAs can be toxic to cells. Increased blood concentration of oleic acid (OLA and other fatty acids is detected in many pathological conditions. In sepsis and leptospirosis, high plasma levels of NEFA and low albumin concentrations are correlated to the disease severity. Surprisingly, 24 h after intravenous or intragastric administration of OLA, main NEFA levels (OLA inclusive were dose dependently decreased. However, lung injury was detected in intravenously treated mice, and highest dose killed all mice. When administered by the enteral route, OLA was not toxic in any tested conditions. Results indicate that OLA has important regulatory properties on fatty acid metabolism, possibly lowering circulating fatty acid through activation of peroxisome proliferator-activated receptors. The significant reduction in blood NEFA levels detected after OLA enteral administration can contribute to the already known health benefits brought about by unsaturated-fatty-acid-enriched diets.

  9. Enhanced photoluminescence in transparent thin films of polyaniline–zinc oxide nanocomposite prepared from oleic acid modified zinc oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sajimol Augustine, M., E-mail: sajimollazar@gmail.com [Department of Physics, St. Teresa' s College, Kochi-11, Kerala (India); Jeeju, P.P.; Varma, S.J.; Francis Xavier, P.A. [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Kochi-22, Kerala (India); Jayalekshmi, S., E-mail: lakshminathcusat@gmail.com [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Kochi-22, Kerala (India)

    2014-07-01

    Oleic acid capped zinc oxide (ZnO) nanoparticles have been synthesized by a wet chemical route. The chemical oxidative method is employed to synthesize polyaniline (PANI) and PANI/ZnO nanocomposites doped with four different dopants such as orthophosphoric acid (H{sub 3}PO{sub 4}), hydrochloric acid (HCl), naphthalene-2-sulphonic acid and camphor sulphonic acid (CSA). The samples have been structurally characterized by X-ray diffraction (XRD), field emission scanning electron microscopy and Fourier transform infrared (FT-IR) spectroscopic techniques. A comparison of the photoluminescence (PL) emission intensity of PANI and PANI/ZnO nanocomposites is attempted. The enhanced PL intensity in PANI/ZnO nanocomposites is caused by the presence of nanostructured and highly fluorescent ZnO in the composites. It has been observed that, among the composites, the H{sub 3}PO{sub 4} doped PANI/ZnO nanocomposite is found to exhibit the highest PL intensity because of the higher extent of (pi) conjugation and the more orderly arrangement of the benzenoid and quinonoid units. In the present work, transparent thin films of PANI and PANI/ZnO nanocomposite for which PL intensity is found to be maximum, have been prepared after re-doping with CSA by the spin-coating technique. The XRD pattern of the PANI/ZnO film shows exceptionally good crystallanity compared to that of pure PANI, which suggests that the addition of ZnO nanocrystals helps in enhancing the crystallanity of the PANI/ZnO nanocomposite. There is a significant increase in the PL emission intensity of the PANI/ZnO nanocomposite film making it suitable for the fabrication of optoelectronic devices. - Highlights: • Oleic acid capped zinc oxide nanoparticles are synthesized by wet chemical method. • Polyaniline/zinc oxide nanocomposites are prepared by in-situ polymerization. • Polyaniline and polyaniline/zinc oxide thin films are deposited using spin-coating. • Enhanced photoluminescence is observed in polyaniline

  10. Growth of catalase A and catalase T deficient mutant strains of Saccharomyces cerevisiae on ethanol and oleic acid : Growth profiles and catalase activities in relation to microbody proliferation

    NARCIS (Netherlands)

    Klei, Ida J. van der; Rytka, Joanna; Kunau, Wolf H.; Veenhuis, Marten

    1990-01-01

    The parental strain (A+T+) of Saccharomyces cerevisiae and mutants, deficient in catalase T (A+T-), catalase A (A-T+) or both catalases (A-T-), grew on ethanol and oleic acid with comparable doubling times. Specific activities of catalase were low in glucose- and ethanol-grown cells. In the two olei

  11. Oleic acid-dependent modulation of Nitric oxide associated 1 protein levels regulates nitric oxide-mediated defense signaling in Arabidopsis

    Science.gov (United States)

    The conserved cellular metabolites nitric oxide (NO) and oleic acid (18:1) are well-known regulators of disease physiologies in diverse organism. We show that NO production in plants is regulated via 18:1. Reduction in 18:1 levels, via a genetic mutation in the 18:1-synthesizing gene SUPPRESSOR OF S...

  12. Counteracting foaming caused by lipids or proteins in biogas reactors using rapeseed oil or oleic acid as antifoaming agents.

    Science.gov (United States)

    Kougias, P G; Boe, K; Einarsdottir, E S; Angelidaki, I

    2015-08-01

    Foaming is one of the major operational problems in biogas plants, and dealing with foaming incidents is still based on empirical practices. Various types of antifoams are used arbitrarily to combat foaming in biogas plants, but without any scientific support this action can lead to serious deterioration of the methanogenic process. Many commercial antifoams are derivatives of fatty acids or oils. However, it is well known that lipids can induce foaming in manure based biogas plants. This study aimed to elucidate the effect of rapeseed oil and oleic acid on foam reduction and process performance in biogas reactors fed with protein or lipid rich substrates. The results showed that both antifoams efficiently suppressed foaming. Moreover rapeseed oil resulted in stimulation of the biogas production. Finally, it was reckoned that the chemical structure of lipids, and more specifically their carboxylic ends, is responsible for their foam promoting or foam counteracting behaviour. Thus, it was concluded that the fatty acids and oils could suppress foaming, while salt of fatty acids could generate foam.

  13. SFH2 regulates fatty acid synthase activity in the yeast Saccharomyces cerevisiae and is critical to prevent saturated fatty acid accumulation in response to haem and oleic acid depletion.

    Science.gov (United States)

    Desfougères, Thomas; Ferreira, Thierry; Bergès, Thierry; Régnacq, Matthieu

    2008-01-01

    The yeast Saccharomyces cerevisiae is a facultative anaerobic organism. Under anaerobiosis, sustained growth relies on the presence of exogenously supplied unsaturated fatty acids and ergosterol that yeast is unable to synthesize in the absence of oxygen or upon haem depletion. In the absence of exogenous supplementation with unsaturated fatty acid, a net accumulation of SFA (saturated fatty acid) is observed that induces significant modification of phospholipid profile [Ferreira, Régnacq, Alimardani, Moreau-Vauzelle and Bergès (2004) Biochem. J. 378, 899-908]. In the present paper, we focus on the role of SFH2/CSR1, a hypoxic gene related to SEC14 and its involvement in lipid metabolism upon haem depletion in the absence of oleic acid supplementation. We observed that inactivation of SFH2 results in enhanced accumulation of SFA and phospholipid metabolism alterations. It results in premature growth arrest and leads to an exacerbated sensitivity to exogenous SFA. This phenotype is suppressed in the presence of exogenous oleic acid, or by a controlled expression of FAS1, one of the two genes encoding FAS. We present several lines of evidence to suggest that Sfh2p and oleic acid regulate SFA synthase in yeast at different levels: whereas oleic acid acts on FAS2 at the transcriptional level, we show that Sfh2p inhibits fatty acid synthase activity in response to haem depletion. PMID:17803462

  14. Adsorption of naphthalene from aqueous solution onto fatty acid modified walnut shells.

    Science.gov (United States)

    Zhu, Mijia; Yao, Jun; Dong, Lifu; Sun, Jingjing

    2016-02-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from aqueous solution is challenging to environmental technologists. Agricultural waste is apparently the most attractive materials in removing PAHs because of its abundance, renewability, and economic advantage. The adsorption of PAHs (e.g., naphthalene) onto walnut shell (WNS) and its fatty acid (e.g., capric acid, lauric acid, palmitic acid, and oleic acid)-modified equivalent were investigated in this work to develop low-cost biosorbents for hydrophobic organic compounds. Compared with other modified sorbents, oleic acid graftted walnut shell (OWNS) showed the maximum partition coefficient (4330 ± 8.8 L kg(-1)) because of its lowest polarity and highest aromaticity. The adsorption capacity (7210 μg g(-1)) of OWNS at the temperature of 298 K was observed for an initial naphthalene concentration of 25 mg L(-1) with contact time of 40 h, sorbent dosage of 1 g L(-1), and in neutral condition. Furthermore, the regeneration capability of OWNS implied that it was a promising biosorbent for naphthalene removal. PMID:26517393

  15. Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

    OpenAIRE

    Bloemen, Maarten; Brullot, Ward; Luong, Thien Tai; Geukens, Nick; Gils, Ann; Verbiest, Thierry

    2012-01-01

    Superparamagnetic iron oxide nanoparticles can provide multiple benefits for biomedical applications in aqueous environments such as magnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane excha...

  16. Effects of oleic acid and olive oil on gastric emptying, gut hormone secretion and appetite in lean and overweight or obese males

    DEFF Research Database (Denmark)

    Damgaard, Morten; Graff, Jesper; Fuglsang, Stefan;

    2013-01-01

    lean subjects, free fatty acid (FFA) promotes gut hormone release, delays gastric emptying, and reduces appetite and energy intake more than an isocaloric load of triglyceride (TG). In obesity, the gastrointestinal sensitivity to lipids may be reduced. Therefore, we compared the effects of the FF...... oleic acid and the TG olive oil on gut hormone secretion, gastric emptying, appetite, and energy intake in lean and overweight/obese subjects....

  17. Large Ferrierite Crystals as Models for Catalyst Deactivation during Skeletal Isomerisation of Oleic Acid: Evidence for Pore Mouth Catalysis.

    Science.gov (United States)

    Wiedemann, Sophie C C; Ristanović, Zoran; Whiting, Gareth T; Reddy Marthala, V R; Kärger, Jörg; Weitkamp, Jens; Wels, Bas; Bruijnincx, Pieter C A; Weckhuysen, Bert M

    2016-01-01

    Large zeolite crystals of ferrierite have been used to study the deactivation, at the single particle level, of the alkyl isomerisation catalysis of oleic acid and elaidic acid by a combination of visible micro-spectroscopy and fluorescence microscopy (both polarised wide-field and confocal modes). The large crystals did show the desired activity, albeit only traces of the isomerisation product were obtained and low conversions were achieved compared to commercial ferrierite powders. This limited activity is in line with their lower external non-basal surface area, supporting the hypothesis of pore mouth catalysis. Further evidence for the latter comes from visible micro-spectroscopy, which shows that the accumulation of aromatic species is limited to the crystal edges, while fluorescence microscopy strongly suggests the presence of polyenylic carbocations. Light polarisation associated with the spatial resolution of fluorescence microscopy reveals that these carbonaceous deposits are aligned only in the larger 10-MR channels of ferrierite at all crystal edges. The reaction is hence further limited to these specific pore mouths. PMID:26611940

  18. Combined effect of oleic acid and propylene glycol on the percutaneous penetration of tenoxicam and its retention in the skin.

    Science.gov (United States)

    Larrucea, E; Arellano, A; Santoyo, S; Ygartua, P

    2001-09-01

    The influence of oleic acid (OA) on the in vitro percutaneous absorption of tenoxicam (TEN) and its combined effect with propylene glycol (PG) was studied using Franz-type diffusion cells. Furthermore, at defined concentrations of OA, complexes of the drug with cyclodextrins (MbetaCD and gammaCD) were added because their combined use may be an interesting approach to raise TEN flux. In addition, the amount of TEN retained in the skin after topical administration of several formulations was determined. It was found that OA content markedly increased TEN absorption when compared to the control gel; the highest drug flux was obtained by 15% of OA. The absorption rate of TEN increased in parallel with increasing OA concentration, due to the alteration of the stratum corneum caused by this enhancer. Moreover, the action of OA is likely to be strongly dependent on the vehicle used since drug penetration tended to increase with increasing PG content in the vehicle, especially at the high OA concentrations. Contrary to our expectations, addition of CD complexes did not produce a significant further enhancement. Skin pretreatment with OA, independently of the vehicle used to dissolve the fatty acid, dramatically improved TEN percutaneous penetration. The amount of TEN retained in the skin was related to the flux values obtained with each formulation. PMID:11522475

  19. Large Ferrierite Crystals as Models for Catalyst Deactivation during Skeletal Isomerisation of Oleic Acid: Evidence for Pore Mouth Catalysis.

    Science.gov (United States)

    Wiedemann, Sophie C C; Ristanović, Zoran; Whiting, Gareth T; Reddy Marthala, V R; Kärger, Jörg; Weitkamp, Jens; Wels, Bas; Bruijnincx, Pieter C A; Weckhuysen, Bert M

    2016-01-01

    Large zeolite crystals of ferrierite have been used to study the deactivation, at the single particle level, of the alkyl isomerisation catalysis of oleic acid and elaidic acid by a combination of visible micro-spectroscopy and fluorescence microscopy (both polarised wide-field and confocal modes). The large crystals did show the desired activity, albeit only traces of the isomerisation product were obtained and low conversions were achieved compared to commercial ferrierite powders. This limited activity is in line with their lower external non-basal surface area, supporting the hypothesis of pore mouth catalysis. Further evidence for the latter comes from visible micro-spectroscopy, which shows that the accumulation of aromatic species is limited to the crystal edges, while fluorescence microscopy strongly suggests the presence of polyenylic carbocations. Light polarisation associated with the spatial resolution of fluorescence microscopy reveals that these carbonaceous deposits are aligned only in the larger 10-MR channels of ferrierite at all crystal edges. The reaction is hence further limited to these specific pore mouths.

  20. Oleic acid, hydroxytyrosol and n-3 fatty acids collectively modulate colitis through reduction of oxidative stress and IL-8 synthesis; in vitro and in vivo studies.

    Science.gov (United States)

    Reddy, K Vijay Kumar; Naidu, K Akhilender

    2016-06-01

    Our recent study has demonstrated that medium chain triglycerides (MCT) and monounsaturated fatty acids potentiate the beneficial effects of fish oil on risk factors of cardiovascular disease. In the present study, we have investigated the influence of MCT or olive oil on the protective and mucosal healing ability of fish oil in ulcerative colitis using cell simulation and animal models. Caco-2 cells grown in medium chain fatty acids enriched medium has exaggerated t-butyl hydroperoxide induced cell damage, GSH depletion, and IL-1β induced IL-8 synthesis, compared to the cells grown in oleic acid & hydroxytyrosol (OT) enriched medium. Further, combined treatment of cells with eicosapentaenoic acid, docosahexaenoic acid, and OT has remarkably attenuated the cell damage, and IL-8 synthesis, compared to individual treatments. To evaluate the effect of these lipid formulations in vivo, adult Wistar rats were fed diet enriched with high amount of medium chain triglycerides (MCT), virgin olive oil, or their combination with fish oil. Colitis was induced in rats using dextran sulfate sodium (DSS) for 7days followed by 10-days of recovery period. Rats of MCT group exhibit severe disease activity, higher levels of inflammatory cytokines in the colon compared to the olive oil group. Furthermore, there was persistent body weight loss, loose stools, higher levels of inflammatory cytokines in the rats of MCT group, even after DSS was withdrawn from drinking water. Conversely, fish oil has remarkably attenuated the DSS induced alterations in both MCT and olive oil diet groups with significantly greater effect in the olive oil group. Thus, MCT increase the susceptibility to colitis through oxidative damage and IL-8 synthesis in intestinal epithelial cells. The beneficial effects of virgin olive oil could be partially attributed to hydroxytyrosol. Combined treatment of hydroxytyrosol, oleic acid and n-3 fatty acids exhibit huge therapeutic benefits in colitis. PMID:27016717

  1. NIR Spectroscopic Properties of Aqueous Acids Solutions

    Directory of Open Access Journals (Sweden)

    Mohd Zubir MatJafri

    2012-06-01

    Full Text Available Acid content is one of the important quality attributes in determining the maturity index of agricultural product, particularly fruits. Despite the fact that much research on the measurement of acidity in fruits through non-destructive spectroscopy analysis at NIR wavelengths between 700 to 1,000 nm has been conducted, the same response towards individual acids is not well known. This paper presents NIR spectroscopy analysis on aqueous citric, tartaric, malic and oxalic solutions through quantitative analysis by selecting a set of wavelengths that can best be used to measure the pH of the solutions. The aquaphotomics study of the acid solutions has generated R2 above 0.9 for the measurement of all acids. The most important wavelengths for pH are located at 918–925 nm and 990–996 nm, while at 975 nm for water.

  2. Effects of medium-chain fatty acids and oleic acid on blood lipids, lipoproteins, glucose, insulin, and lipid transfer protein activities

    DEFF Research Database (Denmark)

    Tholstrup, T.; Ehnholm, C.; Jauhiainen, M.;

    2004-01-01

    design, 17 healthy young men replaced part of their habitual dietary fat intake with 70 g MCTs (66% 8:0 and 34% 10:0) or high-oleic sunflower oil (89.4% 18:1). Each intervention period lasted 21 d, and the 2 periods were separated by a washout period of 2 wk. Blood samples were taken before and after...... the intervention periods. Results: Compared with the intake of high-oleic sunflower oil, MCT intake resulted in 11% higher plasma total cholesterol (P = 0.0005), 12% higher LDL cholesterol (P = 0.0001), 32% higher VLDL cholesterol (P = 0.080), a 12% higher ratio of LDL to HDL cholesterol (P = 0.002), 22% higher......Background: Dietary medium-chain fatty acids (MCFAs) are of nutritional interest because they are more easily absorbed from dietary medium-chain triacylglycerols (MCTs) than are long-chain fatty acids from, for example, vegetable oils. It has generally been claimed that MCFAs do not increase plasma...

  3. Oleic acid exposure of cultured endothelial cells alters lipid mediator production

    Science.gov (United States)

    Diesel, biodiesel, and other combustion sources contain free fatty acid (FFA) components capable of entering the body through particulate inhalation. FFA can also be endogenously released into circulation in response to stress. When in circulation, bioactive FFA may interact with...

  4. Antioxidative Activities of Both Oleic Acid and Camellia tenuifolia Seed Oil Are Regulated by the Transcription Factor DAF-16/FOXO in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Chia-Cheng Wei

    Full Text Available Tea seed oil is a high quality edible oil, yet lacking sufficient scientific evidences to support the nutritional and medical purposes. We identified major and minor components in Camellia tenuifolia seed oil and investigated the antioxidative activity and its underlying mechanisms in Caenorhabditis elegans.The results showed that the major constitutes in C. tenuifolia seed oil were unsaturated fatty acids (~78.4%. Moreover, two minor compounds, β-amyrin and β-sitosterol, were identified and their antioxidative activity was examined. We found that oleic acid was the major constitute in C. tenuifolia seed oil and plays a key role in the antioxidative activity of C. tenuifolia seed oil in C. elegans.This study found evidences that the transcription factor DAF-16/FOXO was involved in both oleic acid- and C. tenuifolia seed oil-mediated oxidative stress resistance in C. elegans. This study suggests the potential of C. tenuifolia seed oil as nutrient or functional foods.

  5. Cyclopiazonic acid degradation by aqueous ozone

    OpenAIRE

    Silva, Otniel Freitas; Venâncio, Armando

    2011-01-01

    Ozone is a chemical agent with great potential to reduce mycotoxins, it was effective against to reduce some mycotoxins. In view of this it was aimed of this work study the Cyclopiazonic acid (CPA) degradation by aqueous ozone. The degradation of exogenously CPA introduced in mobile phase was confirmed by High performance liquid Chromatography (HPLC). In parallel it was tested the effect of sodium formate (SF), to evaluate the influence of this chemical to neutralize ...

  6. Covalent immobilization of Candida rugosa lipase on aldehyde functionalized hydrophobic support and the application for synthesis of oleic acid ester.

    Science.gov (United States)

    Temoçin, Zülfikar

    2013-01-01

    This study focuses on Candida rugosa lipase (CRL) immobilization by covalent attachment on poly(ethylene terephthalate)-grafted glycidyl methacrylate (PET-g-GMA) fiber. The immobilization yielded a protein loading of 2.38 mg g(-1) of PET-g-GMA fiber. The performances of the immobilized and free CRLs were evaluated with regard to hydrolysis of olive oil and esterification of oleic acid. The optimum activity pH of the CRL was changed by immobilization to neutral range. The maximum activity of the free and immobilized CRLs occurred at 40 and 45 °C respectively. The immobilized lipase retained 65% of its original activity at 50 °C for 2 h. It was found that the immobilized lipase stored at 4 °C retained 90% of its original activity after 35 days, whereas the free lipase stored at 4 °C retained 69% of its original activity after the same period. In the esterification experiments, the immobilized CRL could maintain a high activity at a water content range from 1.5 to 6% (v/v), while the activity of free CRL showed a clear dependence on water content and decreased rapidly at above 3% (v/v) water content. In addition, after five reuses, the esterification percent yield of the immobilized CRL slightly decreased from 29 to 27%. PMID:23574345

  7. Optical and structural characterization of oleic acid-stabilized CdTe nanocrystals for solution thin film processing

    Directory of Open Access Journals (Sweden)

    Claudio Davet Gutiérrez-Lazos

    2014-06-01

    Full Text Available This work presents results of the optical and structural characterization of oleic acid-stabilized cadmium telluride nanocrystals (CdTe-NC synthesized by an organometallic route. After being cleaned, the CdTe-NC were dispersed in toluene to obtain an ink-like dispersion, which was drop-cast on glass substrate to deposit a thin film. The CdTe-NC colloidal dispersion as well as the CdTe drop-cast thin films were characterized with regard to the optical and structural properties. TEM analysis indicates that the CdTe-NC have a nearly spherical shape (3.5 nm as mean size. Electron diffraction and XRD diffraction analyses indicated the bulk-CdTe face-centered cubic structure for CdTe-NC. An additional diffraction line corresponding to the octahedral Cd3P2 was also detected as a secondary phase, which probably originates by reacting free cadmium ions with trioctylphosphine (the tellurium reducing agent. The Raman spectrum exhibits two broad bands centered at 141.6 and 162.3 cm−1, which could be associated to the TO and LO modes of cubic CdTe nanocrystals, respectively. Additional peaks located in the 222 to 324 cm−1 range, agree fairly well with the wavenumbers reported for TO modes of octahedral Cd3P2.

  8. The Effect of Chemical Structure on Pour Point, Oxidative Stability and Tribological Properties of Oleic Acid Triester Derivatives

    International Nuclear Information System (INIS)

    Due to the strict regulations imposed on non-biodegradable mineral oil-based lubricants, the development and applications of bio lubricants are increasing daily. Plant oils are being investigated as a potential source of environmentally favorable lubricants because of their biodegradability, renewability, viscosity-temperature relationship, low volatility and excellent lubrication performance. However, the use of plant oils has some restriction, the most critical being oxidative stability and low-temperature problems. This paper presents systematic modifications to improve the physicochemical and tribological properties of plant oil derivatives. The results showed that among the oleic acid-based triester compounds, 2-ethylhexyl 9-(myristoxy)-10-(heptanoyloxy)octadecanoate (9) had the lowest pour point (-47.19 degree Celsius) while 2-ethylhexyl 9-(caprooxy)-10-(heptanoyloxy)octadecanoate (5) had the highest onset temperature (103.10 degree Celsius). Overall, the data indicate that the bio lubricant base stocks based on this chemical modification offer great potential for the development of industrial products application. (author)

  9. Wear-resistant and electromagnetic absorbing behaviors of oleic acid post-modified ferrite-filled epoxy resin composite coating

    Science.gov (United States)

    Wang, Wenjie; Zang, Chongguang; Jiao, Qingjie

    2015-03-01

    The post-modified Mn-Zn ferrite was prepared by grafting oleic acid on the surface of Mn-Zn ferrite to inhibit magnetic nanoparticle aggregation. Fourier Transform Infrared (FT-IR) spectroscopy was used to characterize the particle surfaces. The friction and electromagnetic absorbing properties of a thin coating fabricated by dispersing ferrite into epoxy resin (EP) were investigated. The roughness of the coating and water contact angle were measured using the VEECO and water contact angle meter. Friction tests were conducted using a stainless-steel bearing ball and a Rockwell diamond tip, respectively. The complex permittivity and complex permeability of the composite coating were studied in the low frequency (10 MHz-1.5 GHz). Surface modified ferrites are found to improve magnetic particles dispersion in EP resulting in significant compatibility between inorganic and organic materials. Results also indicate that modified ferrite/EP coatings have a lower roughness average value and higher water contact angle than original ferrite/EP coatings. The enhanced tribological properties of the modified ferrite/EP coatings can be seen from the increased coefficient value. The composite coatings with modified ferrite are observed to exhibit better reflection loss compared with the coatings with original ferrite.

  10. Physiological study on CT image analysis of acute pulmonary edema by oleic acid and its application to diagnosis of drowning

    International Nuclear Information System (INIS)

    Recently, various investigations are carried out about the relationship between the pathophysiological changes and the images of the destructive extent in acute lung injury. In present paper, we examined, in progression time, the pathophysiological and histological changes basing upon pulmonary edema model made by administration of oleic acid to beagle dogs, and simultaneously took images of the lung by employing high-resolution X-ray CT and analyzed them. In pathophysiological and histological investigation, VA/Q heterogeneity and lung water volume increased, and decrease of PO2 in arterial blood was observed, and also filling of the alveoli with exudate, edema of the alveolar interstitium, congestion of the alveoli were observed histologically. In image analysis, the findings, that is enough to reflect the pathophysiological and histological changes, were obtained from mean CT value and the distribution of CT value histogram. Moreover, the same examination as in acute pulmonary edema model was carried out in drowning model with seawater. Consequently, it became evident that presuming of pathophysiological changes in drowning was possible from results of X-ray CT image analysis. The results described above seem to indicate that X-ray CT image analysis in acute lung injury can use as an index of the damage degree, and also is available for elucidation of the pathophysiological changes. (author)

  11. Nitro-oleic acid modulates classical and regulatory activation of macrophages and their involvement in pro-fibrotic responses.

    Science.gov (United States)

    Ambrozova, Gabriela; Martiskova, Hana; Koudelka, Adolf; Ravekes, Thorben; Rudolph, Tanja K; Klinke, Anna; Rudolph, Volker; Freeman, Bruce A; Woodcock, Steven R; Kubala, Lukas; Pekarova, Michaela

    2016-01-01

    Inflammation is an immune response triggered by microbial invasion and/or tissue injury. While acute inflammation is directed toward invading pathogens and injured cells, thus enabling tissue regeneration, chronic inflammation can lead to severe pathologies and tissue dysfunction. These processes are linked with macrophage polarization into specific inflammatory "M1-like" or regulatory "M2-like" subsets. Nitro-fatty acids (NO2-FAs), produced endogenously as byproducts of metabolism and oxidative inflammatory conditions, may be useful for treating diseases associated with dysregulated immune homeostasis. The goal of this study was to characterize the role of nitro-oleic acid (OA-NO2) in regulating the functional specialization of macrophages induced by bacterial lipopolysaccharide or interleukin-4, and to reveal specific signaling mechanisms which can account for OA-NO2-dependent modulation of inflammation and fibrotic responses. Our results show that OA-NO2 inhibits lipopolysaccharide-stimulated production of both pro-inflammatory and immunoregulatory cytokines (including transforming growth factor-β) and inhibits nitric oxide and superoxide anion production. OA-NO2 also decreases interleukin-4-induced macrophage responses by inhibiting arginase-I expression and transforming growth factor-β production. These effects are mediated via downregulation of signal transducers and activators of transcription, mitogen-activated protein kinase and nuclear factor-кB signaling responses. Finally, OA-NO2 inhibits fibrotic processes in an in vivo model of angiotensin II-induced myocardial fibrosis by attenuating expression of α-smooth muscle actin, systemic transforming growth factor-β levels and infiltration of both "M1-" and "M2-like" macrophage subsets into afflicted tissue. Overall, the electrophilic fatty acid derivative OA-NO2 modulates a broad range of "M1-" and "M2-like" macrophage functions and represents a potential therapeutic approach to target diseases

  12. Starch nanoparticles formed by rapidly cooling dispersions of amylose-oleic acid complexes

    Science.gov (United States)

    There is increasing interest in the preparation of starch-based nanoparticles for a variety of uses, such as biobased fillers in polymeric matrices to improve structural or barrier properties. Most established methods for preparing these nanoparticles involve acid hydrolysis of starch coupled with m...

  13. Targeted mutation of Δ12 and Δ15 desaturase genes in hemp produce major alterations in seed fatty acid composition including a high oleic hemp oil.

    Science.gov (United States)

    Bielecka, Monika; Kaminski, Filip; Adams, Ian; Poulson, Helen; Sloan, Raymond; Li, Yi; Larson, Tony R; Winzer, Thilo; Graham, Ian A

    2014-06-01

    We used expressed sequence tag library and whole genome sequence mining to identify a suite of putative desaturase genes representing the four main activities required for production of polyunsaturated fatty acids in hemp seed oil. Phylogenetic-based classification and developing seed transcriptome analysis informed selection for further analysis of one of seven Δ12 desaturases and one of three Δ15 desaturases that we designate CSFAD2A and CSFAD3A, respectively. Heterologous expression of corresponding cDNAs in Saccharomyces cerevisiae showed CSFAD2A to have Δx+3 activity, while CSFAD3A activity was exclusively at the Δ15 position. TILLING of an ethyl methane sulphonate mutagenized population identified multiple alleles including non-sense mutations in both genes and fatty acid composition of seed oil confirmed these to be the major Δ12 and Δ15 desaturases in developing hemp seed. Following four backcrosses and sibling crosses to achieve homozygosity, csfad2a-1 was grown in the field and found to produce a 70 molar per cent high oleic acid (18:1(Δ9) ) oil at yields similar to wild type. Cold-pressed high oleic oil produced fewer volatiles and had a sevenfold increase in shelf life compared to wild type. Two low abundance octadecadienoic acids, 18:2(Δ6,9) and 18:2(Δ9,15), were identified in the high oleic oil, and their presence suggests remaining endogenous desaturase activities utilize the increased levels of oleic acid as substrate. Consistent with this, CSFAD3A produces 18:2(Δ9,15) from endogenous 18:1(Δ9) when expressed in S. cerevisiae. This work lays the foundation for the development of additional novel oil varieties in this multipurpose low input crop.

  14. A case study on the genetic origin of the high oleic acid trait through FAD2-1 DNA sequence variation in safflower (Carthamus tinctorius L.

    Directory of Open Access Journals (Sweden)

    Sara eRapson

    2015-09-01

    Full Text Available The safflower (Carthamus tinctorius L. is considered a strongly domesticated species with a long history of cultivation. The hybridization of safflower with its wild relatives has played an important role in the evolution of cultivars and is of particular interest with regards to their production of high quality edible oils. Original safflower varieties were all rich in linoleic acid, while varieties rich in oleic acid have risen to prominence in recent decades. The high oleic acid trait is controlled by a partially recessive allele ol at a single locus OL. The ol allele was found to be a defective microsomal oleate desaturase FAD2-1. Here we present DNA sequence data and DNA Southern blot analysis suggesting that there has been an ancient hybridization and introgression of the FAD2-1 gene into C. tinctorius from its wild relative C. palaestinus. It is from this gene that FAD2-1Δ was derived more recently. Identification and characterization of the genetic origin and diversity of FAD2-1 could aid safflower breeders in reducing population size and generations required for the development of new high oleic acid varieties by using perfect molecular marker-assisted selection.

  15. PALMITIC AND OLEIC ACIDS AND THEIR ROLE IN PATHOGENESIS OF ATHEROSCLEROSIS

    Directory of Open Access Journals (Sweden)

    V. N. Titov

    2014-01-01

    Full Text Available On the basis of phylogenetic theory of general pathology, the cause of a noninfectious disease whose occurrence in a population is more than 5–7% is an impaired biological function or reaction to the environment. From the general biology viewpoint, high mortality rate related to cardio-vascular diseases and atherosclerosis (intercellular deficiency of polyenic fatty acids (PFA is just extinction of the Homo sapiens population upon adaptation to new environmental factors. The biological function of throphology (feeding and biological reaction of exotrophy (external feeding are impaired in several aspects, the major of which is nonphysiologically high dietary content of saturated fatty acids, primarily, of palmitic fatty acid (FA. The lipoprotein system formed at early stages of phylogenesis cannot transport and provide physiological deposition of great amounts of palmitic FA, which leads to the development of an adaption (compensatory and accumulation disease. This results in hypermipidemia, impaired bioavailability of PFA to cells, compesatory production of humoral mediators from ω-9 eicosatrienoic mead FA, disorders in physiological parameters of cell plasma membrane and integral proteins, nonphysiological conformation of apoВ-100 in lipoproteins, formation of ligandless lipoproteins (biological litter and impairments in the biological function of endoecology, utilization of ligandless lipoproteins in arterial intima by phylogenetically early macrophages that do not hydrolyze polyenic cholesterol esters, increase in the intensity of the biological reaction of inflammation, and destructive and inflammatory lesions in arterial intima of an atheromatosis or atherothrombosis type. Atheromatous masses are catabolites of PFA which were not internalized by phylogenetically late cells via receptor-mediated pathway.

  16. Clinical experience of immunotherapy based on oleic acid bound to glycosylated vitamin d-binding protein in localised and metastatic adenocarcinoma of the pancreas

    OpenAIRE

    Lynda Thyer; Branca, Jacopo J. V.; Margit Taubmann

    2014-01-01

    Adenocarcinoma of the pancreas still carries a dramatically poor prognosis and the survival rate for this disease has not improved substantially in the past 40 years. Therefore, new treatment options are urgently needed and this need motivates oncologists to search for novel approaches such as immunotherapy. Here we report two clinical cases successfully treated with an integrative immunotherapeutic approach based on oleic acid bound to glycosylated vitamin D-binding protein (OA-GcMAF). Consi...

  17. Extensive feeding versus oleic acid and tocopherol enriched mixed diets for the production of Iberian dry-cured hams: Effect on chemical composition, oxidative status and sensory traits.

    Science.gov (United States)

    Ventanas, S; Ventanas, J; Tovar, J; García, C; Estévez, M

    2007-10-01

    The present study aimed to analyse the chemical composition and oxidative status of Iberian dry-cured hams from pigs fed different finishing diets: extensive feeding on acorns and pasture in a "Montanera" traditional system (MON), fed in confinement with a mixed diet containing high-oleic sunflower oil (115g/kg of diet) and supplemented with 250mg/kg α-tocopherol (HOVE), and fed in confinement control mixed diet (CON) without added tocopherol and oleic acid fat. Muscles from MON dry-cured hams contained significantly (p<0.05) higher amounts of intramuscular fat (IMF) than those from HOVE and CON hams. The feeding background affected the tocopherol levels in dry-cured hams as those from MON and HOVE pigs had significantly higher levels of α-tocopherol than those from CON pigs whereas the extensive feeding provided muscles from MON pigs with significantly higher levels of γ-tocopherol than the experimental diets did to CON and HOVE pigs. The HOVE diet significantly increased the levels of oleic acid in Iberian dry-cured hams with these levels being similar to the oleic acid levels found in MON hams and significantly higher than those in CON hams. Compared to dry-cured hams from CON pigs, those from MON and HOVE pigs exhibited a higher oxidative stability as a likely result of a most favourable fatty acid composition and the presence of higher tocopherol levels. The principal component analysis (PCA) successfully discriminated between dry-cured hams from pigs fed different finishing diets.

  18. Additive regulation of adiponectin expression by the mediterranean diet olive oil components oleic Acid and hydroxytyrosol in human adipocytes.

    Directory of Open Access Journals (Sweden)

    Egeria Scoditti

    Full Text Available Adiponectin, an adipocyte-derived insulin-sensitizing and anti-inflammatory hormone, is suppressed in obesity through mechanisms involving chronic inflammation and oxidative stress. Olive oil consumption is associated with beneficial cardiometabolic actions, with possible contributions from the antioxidant phenol hydroxytyrosol (HT and the monounsaturated fatty acid oleic acid (OA, 18:1n-9 cis, both possessing anti-inflammatory and vasculo-protective properties. We determined the effects of HT and OA, alone and in combination, on adiponectin expression in human and murine adipocytes under pro-inflammatory conditions induced by the cytokine tumor necrosis factor(TNF-α. We used human Simpson-Golabi-Behmel syndrome (SGBS adipocytes and murine 3T3-L1 adipocytes as cell model systems, and pretreated them with 1-100 μmol/L OA, 0.1-20 μmol/L HT or OA plus HT combination before stimulation with 10 ng/mL TNF-α. OA or HT significantly (P<0.05 prevented TNF-α-induced suppression of total adiponectin secretion (by 42% compared with TNF-α alone as well as mRNA levels (by 30% compared with TNF-α alone. HT and OA also prevented-by 35%-TNF-α-induced downregulation of peroxisome proliferator-activated receptor PPARγ. Co-treatment with HT and OA restored adiponectin and PPARγ expression in an additive manner compared with single treatments. Exploring the activation of JNK, which is crucial for both adiponectin and PPARγ suppression by TNF-α, we found that HT and OA additively attenuated TNF-α-stimulated JNK phosphorylation (up to 55% inhibition. In conclusion, the virgin olive oil components OA and HT, at nutritionally relevant concentrations, have additive effects in preventing adiponectin downregulation in inflamed adipocytes through an attenuation of JNK-mediated PPARγ suppression.

  19. Uranyl fluoride luminescence in acidic aqueous solutions

    International Nuclear Information System (INIS)

    Luminescence emission spectra and decay rates are reported for uranyl species in acidic aqueous solutions containing HF or added NaF. The longest luminescence lifetime, 0.269 ± 0.006 ms, was observed from uranyl in 1 M HF + 1 M HClO4 at 296 K and decreased with increasing temperature. Based on a luminescence dynamics model that assumes equilibrium among electronically excited uranyl fluoride species and free fluoride ion, this long lived uranyl luminescence in aqueous solution is attributed primarily to UO2F2. Studies on the effect of added LiNO3 or Na2WO4·2H2O showed relatively weak quenching of uranyl fluoride luminescence which suggests that high sensitivity determination of the UF6 content of WF6 gas should be feasible via uranyl luminescence analysis of hydrolyzed gas samples of impure WF6

  20. Associations between Orosensory Perception of Oleic Acid, the Common Single Nucleotide Polymorphisms (rs1761667 and rs1527483 in the CD36 Gene, and 6-n-Propylthiouracil (PROP Tasting

    Directory of Open Access Journals (Sweden)

    Melania Melis

    2015-03-01

    Full Text Available Orosensory perception of dietary fat varies in individuals, thus influencing nutritional status. Several studies associated fat detection and preference with CD36 or 6-n-propylthiouracil (PROP sensitivity. Other studies have not confirmed the latter association. We analyzed the relationship between orosensory perception of oleic acid, two CD36 variants, and PROP tasting. Thresholds of oleic acid perception were assessed in 64 subjects using a modification of the three-alternative forced-choice procedure. Subjects were classified for PROP taster status and genotyped for TAS2R38 and CD36 (SNPs: rs1761667 and rs1527483. Subjects homozygous for GG of the rs1761667 polymorphism showed higher sensitivity to oleic acid than AA subjects. The capability to detect oleic acid was directly associated with TAS2R38 or PROP responsiveness. PROP non-tasters had a lower papilla density than tasters, and those with genotype GG of the rs1761667 polymorphism had lower oleic acid thresholds than PROP non-tasters with genotype AA. In conclusion, results showed a direct association between orosensory perception of oleic acid and PROP tasting or rs1761667 polymorphism of CD36, which play a significant role in PROP non-tasters, given their low number of taste papillae. Characterization of individual capability to detect fatty acids may have important nutritional implications by explaining variations in human fat preferences.

  1. Structural characterization of more potent alternatives to HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    Science.gov (United States)

    Nemashkalova, Ekaterina L; Kazakov, Alexei S; Khasanova, Leysan M; Permyakov, Eugene A; Permyakov, Sergei E

    2013-09-10

    HAMLET is a complex of human α-lactalbumin (hLA) with oleic acid (OA) that kills various tumor cells and strains of Streptococcus pneumoniae. More potent protein-OA complexes were previously reported for bovine α-lactalbumin (bLA) and β-lactoglobulin (bLG), and pike parvalbumin (pPA), and here we explore their structural features. The concentration dependencies of the tryptophan fluorescence of hLA, bLA, and bLG complexes with OA reveal their disintegration at protein concentrations below the micromolar level. Chemical cross-linking experiments provide evidence that association with OA shifts the distribution of oligomeric forms of hLA, bLA, bLG, and pPA toward higher-order oligomers. This effect is confirmed for bLA and bLG using the dynamic light scattering method, while pPA is shown to associate with OA vesicles. Like hLA binding, OA binding increases the affinity of bLG for small unilamellar dipalmitoylphosphatidylcholine vesicles, while pPA efficiently binds to the vesicles irrespective of OA binding. The association of OA with bLG and pPA increases their α-helix and cross-β-sheet content and resistance to enzymatic proteolysis, which is indicative of OA-induced protein structuring. The lack of excess heat sorption during melting of bLG and pPA in complex with OA and the presence of a cooperative thermal transition at the level of their secondary structure suggest that the OA-bound forms of bLG and pPA lack a fixed tertiary structure but exhibit a continuous thermal transition. Overall, despite marked differences, the HAMLET-like complexes that were studied exhibit a common feature: a tendency toward protein oligomerization. Because OA-induced oligomerization has been reported for other proteins, this phenomenon is inherent to many proteins. PMID:23947814

  2. Structural characterization of more potent alternatives to HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    Science.gov (United States)

    Nemashkalova, Ekaterina L; Kazakov, Alexei S; Khasanova, Leysan M; Permyakov, Eugene A; Permyakov, Sergei E

    2013-09-10

    HAMLET is a complex of human α-lactalbumin (hLA) with oleic acid (OA) that kills various tumor cells and strains of Streptococcus pneumoniae. More potent protein-OA complexes were previously reported for bovine α-lactalbumin (bLA) and β-lactoglobulin (bLG), and pike parvalbumin (pPA), and here we explore their structural features. The concentration dependencies of the tryptophan fluorescence of hLA, bLA, and bLG complexes with OA reveal their disintegration at protein concentrations below the micromolar level. Chemical cross-linking experiments provide evidence that association with OA shifts the distribution of oligomeric forms of hLA, bLA, bLG, and pPA toward higher-order oligomers. This effect is confirmed for bLA and bLG using the dynamic light scattering method, while pPA is shown to associate with OA vesicles. Like hLA binding, OA binding increases the affinity of bLG for small unilamellar dipalmitoylphosphatidylcholine vesicles, while pPA efficiently binds to the vesicles irrespective of OA binding. The association of OA with bLG and pPA increases their α-helix and cross-β-sheet content and resistance to enzymatic proteolysis, which is indicative of OA-induced protein structuring. The lack of excess heat sorption during melting of bLG and pPA in complex with OA and the presence of a cooperative thermal transition at the level of their secondary structure suggest that the OA-bound forms of bLG and pPA lack a fixed tertiary structure but exhibit a continuous thermal transition. Overall, despite marked differences, the HAMLET-like complexes that were studied exhibit a common feature: a tendency toward protein oligomerization. Because OA-induced oligomerization has been reported for other proteins, this phenomenon is inherent to many proteins.

  3. Treatment with a novel oleic-acid-dihydroxyamphetamine conjugation ameliorates non-alcoholic fatty liver disease in obese Zucker rats.

    Science.gov (United States)

    Decara, Juan M; Pavón, Francisco Javier; Suárez, Juan; Romero-Cuevas, Miguel; Baixeras, Elena; Vázquez, Mariam; Rivera, Patricia; Gavito, Ana L; Almeida, Bruno; Joglar, Jesús; de la Torre, Rafael; Rodríguez de Fonseca, Fernando; Serrano, Antonia

    2015-10-01

    Fatty liver disease is one of the main hepatic complications associated with obesity. To date, there are no effective treatments for this pathology apart from the use of classical fibrates. In this study, we have characterized the in vivo effects of a novel conjugation of oleic acid with an amphetamine derivative (OLHHA) in an animal model of genetic obesity. Lean and obese Zucker rats received a daily intraperitoneal administration of OLHHA (5 mg kg(-1)) for 15 days. Plasma and liver samples were collected for the biochemical and molecular biological analyses, including both immunohistochemical and histological studies. The expression of key enzymes and proteins that are involved in lipid metabolism and energy homeostasis was evaluated in the liver samples. The potential of OLHHA to produce adverse drug reactions or toxicity was also evaluated through the monitoring of interactions with hERG channel and liver cytochrome. We found that OLHHA is a drug with a safe pharmacological profile. Treatment for 15 days with OLHHA reduced the liver fat content and plasma triglyceride levels, and this was accompanied by a general improvement in the profile of plasma parameters related to liver damage in the obese rats. A decrease in fat accumulation in the liver was confirmed using histological staining. Additionally, OLHHA was observed to exert anti-apoptotic effects. This hepatoprotective activity in obese rats was associated with an increase in the mRNA and protein expression of the cannabinoid type 1 receptor and a decrease in the expression of the lipogenic enzymes FAS and HMGCR primarily. However, changes in the mRNA expression of certain proteins were not associated with changes in the protein expression (i.e. L-FABP and INSIG2). The present results demonstrate that OLHHA is a potential anti-steatotic drug that ameliorates the obesity-associated fatty liver and suggest the potential use of this new drug for the treatment of non-alcoholic fatty liver disease

  4. Effective Removal of Tetracycline from Aqueous Solution by Organic Acid-Coated Magnetic Nanoparticles.

    Science.gov (United States)

    Guo, Liang; Liang, Yuyan; Chen, Xuelan; Xu, Wei; Wu, Kesheng; Wei, Hua; Xiong, Yonghua

    2016-03-01

    Self-assembled iron oxide nanocomposites are good magnetic nano-adsorbents that can be prepared using simple methods. Four types of organic acid-functionalised (oleic acid, undecenoic acid, caprylic acid or hexanoic acid) magnetic nanoparticles (MNPs) were synthesised through a one-pot chemisorption method for the removal of tetracycline (TC) from aqueous solution. The undecenoic acid-coated MNPs (UA-MNPs) exhibited the highest adsorption efficiency and can be easily retrieved with a low-gradient magnetic separator (0.4 Tesla) at pH 5.0 aqueous solution. The TC adsorption process on the UA-MNPs followed the Langmuir isotherm and the maximum adsorption capacities increased from 86.96 mg g(-1) to 222.2 mg g(-1) with the increase in temperature from 288 K to 318 K. The kinetics of adsorption fits pseudo-second-order model perfectly with a rate constant, 5.946 g mg(-1) min(-1) at 298 K. The positive values of the enthalpy (AH) and the negative value of the free energy (AG) indicated an endothermic and spontaneous adsorption process of TC on the UA-MNPs. Moreover, the UA-MNPs possessed excellent ability to adsorb the other three major types of TC antibiotics, including chlortetracycline, oxytetracycline and doxycycline. PMID:27455621

  5. 尿素包合法制备油莎豆油中的油酸%Preparation of oleic acid from Cyperus esculentus oil by urea adduct method

    Institute of Scientific and Technical Information of China (English)

    郑莲; 敬思群; 王耀祥; 陈政辉

    2015-01-01

    以油莎豆油为原料,采用尿素包合法对油酸进行纯化,通过单因素试验和正交试验,研究了尿素包合过程中甲醇浓度,回流时间,m(尿素):m(混合脂肪酸)比,温度T1和温度T2等因素对油酸纯度的影响.采用气相色谱-质谱联用(gas chromatography-mass spectroscopy,GC-MS)对纯化后的油莎豆油脂肪酸成分进行了分析.结果表明:采用体积分数85%甲醇,m(尿素):m(混合脂肪酸)=8:10,在N2保护下于60℃加热搅拌回流15 min,8℃下保存24 h后,滤液再在-10℃下静置24 h,油酸含量可由77.17%提高到90.72%.尿素包合后油莎豆油主要脂肪酸组成为棕榈酸7.49%,油酸90.72%,硬脂酸1.08%.%Oleic acid was purified by urea adduct method with Cyperus esculentus oil as raw material.The effects of methanol concentration, reflux time, urea/mixed fatty acid (m/m) , temperature T1 and T2 on the purity of oleic acid were observed through single factor experiment and orthogonal test.The fatty acid composition in purified of Cyperus esculentus oil was analyzed by gas chromatography-mass spectrometry (GC-MS).The results showed that the optimum conditions were: 85% methanol as solvent, the ratio of urea/mixed fatty acid (m/m) 0.8, reaction time for 15 min, stirring and refluxing for 2.0 hours at 60 ℃ under N2 protection, incubated at 8 ℃ for 24h, and the filtration was stand for 24h at-10 ℃.Under these conditions, the content of oleic acid was increased to 90.72% from 77.17%.The main fatty acids of Cyperus esculentus oil after urea inclusion were : palmitic acid 7.49% , oleic acid 90.72% and stearic acid 1.08%.

  6. Etheno-DNA adduct formation in rats gavaged with linoleic acid, oleic acid and coconut oil is organ- and gender specific

    International Nuclear Information System (INIS)

    Intake of linoleic acid (LA) increased etheno-DNA adducts induced by lipid peroxidation (LPO) in white blood cells (WBC) of female but not of male volunteers [J. Nair, C.E. Vaca, I. Velic, M. Mutanen, L.M. Valsta, H. Bartsch, High dietary ω-6 polyunsaturated fatty acids drastically increase the formation of etheno-DNA adducts in white blood cells of female subjects, Cancer Epidemiol. Biomarkers Prev. 6 (1997) 597-601]. Etheno-adducts were measured in rats gavaged with LA, oleic acid (OA) and saturated fatty acid rich coconut oil for 30 days. DNA from organs and total WBC was analyzed for 1, N6-ethenodeoxyadenosine (εdA) and 3, N4-ethenodeoxycytidine (εdC) by immunoaffinity/32P-postlabeling. Colon was the most affected target with LA-treatment, where etheno-adducts were significantly elevated in both sexes. In WBC both adducts were elevated only in LA-treated females. Unexpectedly, OA treatment enhanced etheno-adduct levels in prostate 3-9 fold. Our results in rodents confirm the gender-specific increase of etheno-adducts in WBC-DNA, likely due to LPO induced by redox-cycling of 4-hydroxyestradiol. Colon was a target for LPO-derived DNA-adducts in both LA-treated male and female rats, supporting their role in ω-6 PUFA induced colon carcinogenesis

  7. Backbone and sidechain 1H, 13C and 15N resonance assignments of the human brain-type fatty acid binding protein (FABP7) in its apo form and the holo forms binding to DHA, oleic acid, linoleic acid and elaidic acid

    DEFF Research Database (Denmark)

    Oeemig, Jesper S; Jørgensen, Mathilde L; Hansen, Mikka S;

    2009-01-01

    In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid.......In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid....

  8. H3PO4/Al2O3 catalysts: characterization and catalytic evaluation of oleic acid conversion to biofuels and biolubricant

    Directory of Open Access Journals (Sweden)

    Lucia Regina Raddi de Araujo

    2006-06-01

    Full Text Available Al2O3 and H3PO4/Al2O3 catalysts were investigated in the conversion of oleic acid to biofuels and biolubricant at 1 atm and at 623 K. The catalytic tests were performed in a fixed bed and continuous flow reactor, using an oleic acid-catalyst ratio of 4 and N2 as the carrier gas. The reaction products were analyzed by gas chromatography and acidity measurements. N2 adsorption-desorption, X ray diffraction, 31P nuclear magnetic resonance and FT-IR spectroscopy were also employed to evaluate the textural, structural and acidic properties of the catalysts. The results showed that phosphoric acid impregnation improved the alumina decarboxylation activities, generating hydrocarbons in the range of gasoline, diesel oil and lubricant oil. The best catalytic performance was achieved with the highest surface area alumina impregnated with H3PO4, which was the solid that allied high total acidity with a large quantity of mesopores.

  9. Applications of site-specific labeling to study HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    Directory of Open Access Journals (Sweden)

    Natalia Mercer

    Full Text Available BACKGROUND: Alpha-lactalbumin (α-LA is a calcium-bound mammary gland-specific protein that is found in milk. This protein is a modulator of β1,4-galactosyltransferase enzyme, changing its acceptor specificity from N-acetyl-glucosamine to glucose, to produce lactose, milk's main carbohydrate. When calcium is removed from α-LA, it adopts a molten globule form, and this form, interestingly, when complexed with oleic acid (OA acquires tumoricidal activity. Such a complex made from human α-LA (hLA is known as HAMLET (Human A-lactalbumin Made Lethal to Tumor cells, and its tumoricidal activity has been well established. METHODOLOGY/PRINCIPAL FINDINGS: In the present work, we have used site-specific labeling, a technique previously developed in our laboratory, to label HAMLET with biotin, or a fluoroprobe for confocal microscopy studies. In addition to full length hLA, the α-domain of hLA (αD-hLA alone is also included in the present study. We have engineered these proteins with a 17-amino acid C-terminal extension (hLA-ext and αD-hLA-ext. A single Thr residue in this extension is glycosylated with 2-acetonyl-galactose (C2-keto-galactose using polypeptide-α-N-acetylgalactosaminyltransferase II (ppGalNAc-T2 and further conjugated with aminooxy-derivatives of fluoroprobe or biotin molecules. CONCLUSIONS/SIGNIFICANCE: We found that the molten globule form of hLA and αD-hLA proteins, with or without C-terminal extension, and with and without the conjugated fluoroprobe or biotin molecule, readily form a complex with OA and exhibits tumoricidal activity similar to HAMLET made with full-length hLA protein. The confocal microscopy studies with fluoroprobe-labeled samples show that these proteins are internalized into the cells and found even in the nucleus only when they are complexed with OA. The HAMLET conjugated with a single biotin molecule will be a useful tool to identify the cellular components that are involved with it in the tumoricidal

  10. Effect of oleic and conjugated linoleic acid in the diet of broiler chickens on the live growth performances, carcass traits and meat fatty acid profile

    Directory of Open Access Journals (Sweden)

    Stefano Rapaccini

    2010-01-01

    Full Text Available Olive oil and CLA enriched olive oil were compared with each other in a growth trial with broiler chickens, as energy supplements to the diet. A commercial CLA blend was used at the level of 1 kg per 100 kg mixed integrated feed. Two hundred and forty commercial hybrid broilers (Ross 308 were randomly subdivided and allotted to 8 pens of 30 birds each. Four pens of birds were fed the olive oil diet and considered the control group; the other 4 pens were fed the olive oil supplemented with CLA and considered the treated group. The experiment lasted 47 days. The live performance of the treated birds resulted different from the performance of the control ones: the final body weight was slightly lighter (2.544 kg vs 2.639 kg; P≤0.05 with a lower feed intake (4.886 kg feed vs 4.998 kg, P≤0.05 and, of course, an almost perfectly overlapping feed/gain ratio (1.90 vs 1.91. The fatty acid composition of the breast fat of the CLA treated birds resulted enriched by the two major CLA isomers, trans 10 cis 12 and cis 9 trans 11, whereas oleic acid and the linoleic, linolenic and arachidonic polyunsaturated acids showed a decrease (P≤0.05. CLA appears a recommendable ingredient in the diets of broilers as it improves the beneficial characteristics of poultry meat.

  11. Manganese accumulation in membrane fractions of primary astrocytes is associated with decreased γ-aminobutyric acid (GABA) uptake, and is exacerbated by oleic acid and palmitate.

    Science.gov (United States)

    Fordahl, Steve C; Erikson, Keith M

    2014-05-01

    Manganese (Mn) exposure interferes with GABA uptake; however, the effects of Mn on GABA transport proteins (GATs) have not been identified. We sought to characterize how Mn impairs GAT function in primary rat astrocytes. Astrocytes exposed to Mn (500 μM) had significantly reduced (3)H-GABA uptake despite no change in membrane or cytosolic GAT3 protein levels. Co-treatment with 100 μM oleic or palmitic acids (both known to be elevated in Mn neurotoxicity), exacerbated the Mn-induced decline in (3)H-GABA uptake. Mn accumulation in the membrane fraction of astrocytes was enhanced with fatty acid administration, and was negatively correlated with (3)H-GABA uptake. Furthermore, control cells exposed to Mn only during the experimental uptake had significantly reduced (3)H-GABA uptake, and the addition of GABA (50 μM) blunted cytosolic Mn accumulation. These data indicate that reduced GAT function in astrocytes is influenced by Mn and fatty acids accumulating at or interacting with the plasma membrane.

  12. Stearic acids at sn-1, 3 positions of TAG are more efficient at limiting fat deposition than palmitic and oleic acids in C57BL/6 mice.

    Science.gov (United States)

    Gouk, Shiou-Wah; Cheng, Sit-Foon; Ong, Augustine Soon-Hock; Chuah, Cheng-Hock

    2014-04-14

    In the present study, we investigated the effect of long-acyl chain SFA, namely palmitic acid (16:0) and stearic acid (18:0), at sn-1, 3 positions of TAG on obesity. Throughout the 15 weeks of the experimental period, C57BL/6 mice were fed diets fortified with cocoa butter, sal stearin (SAL), palm mid fraction (PMF) and high-oleic sunflower oil (HOS). The sn-1, 3 positions were varied by 16:0, 18:0 and 18:1, whilst the sn-2 position was preserved with 18:1. The HOS-enriched diet was found to lead to the highest fat deposition. This was in accordance with our previous postulation. Upon normalisation of total fat deposited with food intake to obtain the fat:feed ratio, interestingly, mice fed the SAL-enriched diet exhibited significantly lower visceral fat/feed and total fat/feed compared with those fed the PMF-enriched diet, despite their similarity in SFA-unsaturated fatty acid-SFA profile. That long-chain SFA at sn-1, 3 positions concomitantly with an unsaturated FA at the sn-2 position exert an obesity-reducing effect was further validated. The present study is the first of its kind to demonstrate that SFA of different chain lengths at sn-1, 3 positions exert profound effects on fat accretion.

  13. Determination of α-Linoleic Acid, Linoleic Acid and Oleic Acid in Hemp Seed by HPLC%HPLC同时测定火麻仁中α-亚麻酸、亚油酸和油酸含量

    Institute of Scientific and Technical Information of China (English)

    秦建平; 陆艳芹; 罗雪磊; 吴建雄; 李家春; 萧伟

    2012-01-01

    目的:建立同时测定火麻仁中的α-亚麻酸、亚油酸和油酸含量的HPLC方法.方法:色谱柱为Kromasil 100-5 C18(4.6 mm×250 mm,5 μm),以乙腈-o.1%磷酸(80∶20)为流动相,流速1 mL? min-1,柱温30℃,检测波长203 nm.结果:α-亚麻酸在34.625~554 mg? L-1(r=0.999 9),亚油酸在56.375~902 mg?L -1(r=1),油酸在17.125 ~ 274 mg? L-1(r =0.999 9)呈良好的线性关系;平均回收率α-亚麻酸为96.38%,RSD0.93%(n=6);亚油酸为97.79%,RSD 0.92%(n=6);油酸为97.06%,RSD 1.51% (n =6).结论:本法简便准确,专属性强,重复性好,可作为火麻仁的质量控制的参考.%Objective: To establish a HPLC method for the determination of a-linoleic acid, linoleic acid and oleic acid in Hemp Seed. Method; The Kromasil 100-5 C18 (4.6 mm ×250 mm, 5 μm) column was used with a mobile phase of acetonitrile-0. 1% phosphoric acid (80:20) , the flow rate was 1 mL ? Min-1 , the column temperature was at 30 ℃, the detection wavelength was at 203 nm. Result: The linear ranges of a-linoleic acid, linoleic acid and oleic acid were 34. 625-554 mg ? L-1 ( r = 0. 999 9) , 56. 375-902 mg ? L-1 ( r = 1 ) and 17. 125-274 mg ? L-1 (r=0. 999 9) respectively. The average recoveries were 96. 38% with RSD 0. 93% for a-linoleic acid, 97. 79% with RSD 0. 92% for linoleic acid, 97. 06% with RSD 1. 51% for oleic acid. Conclusion; The method can be used to control the quality of a-linoleic acid, linoleic acid and oleic acid in Hemp Seed, which is simple, accurate, convenient, specific and repeatable.

  14. Production and Optimization of Oleic Acid Ethyl Ester Synthesis Using Lipase From Rice Bran (Oryza sativa L. and Germinated Jatropha Seeds (Jatropha curcas L. by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Indro Prastowo

    2015-11-01

    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 Recently, the fatty acid ethyl ester has been synthesized in place of fatty acid methyl ester since ethanol has been more renewable. In this research, oleic acid ethyl ester (OAEE was synthesized using germinated jatropha seeds (Jatropha curcas.L and rice bran (Oryza sativa as source of lipase. The objective of the research was to optimize the synthesis conditions using Response Surface Methodology. Factors, such as crude enzyme concentration, molar ratio of oleic acid to ethanol, and the reaction time, were evaluated. The results show that lipase from germinated jatropha seeds had the hydrolitic and esterifi cation activity about 6.73 U/g and 298.07 U/g, respectively. Lipase from rice bran had the hydrolitic and esterifi cation activity about 10.57 U/g and 324.03 U/g, respectively. The optimum conditions of esterifi cation reaction using germinated jatropha seed lipase as biocatalyst were crude enzyme concentration of 0.31 g/ml, molar ratio of oleic acid to ethanol of 1 : 1.81, and reaction time of 50.9 min. The optimum conditions of esterifi cation reaction using rice bran lipase were crude enzyme concentration of 0.29 g/ml, molar ratio of oleic acid to ethanol of 1 : 2.05, and reaction time of 58.61 min. The obtained amounts of OAEE were 810.77 μmole and 626.92 μmole for lipases from rice bran and germinated jatropha seed, respectively. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;}

  15. 油酸三乙醇胺皂化物的合成%Synthesis and Application of Oleic Acid Esterified Triethanolamine

    Institute of Scientific and Technical Information of China (English)

    甘黎明

    2015-01-01

    The single factor controlling variables method,with saponification value after deducting acid value evalu-ation,study on the reaction ratio,reaction temperature,reaction time on synthesis of triethanolamine oleate.The results show that the oleic acid and triethanolamine ratio of 1.2∶1 (mol /mol),a temperature of 130 ℃,reaction time was 3h,the most abundant system of oleic acid esterified triethanolamine reaction equilibrium.The use of syn-thetic esterified oleic acid triethanolamine deployment of water -based lubricants meets the relevant requirements.%采用单因素控制变量法,以扣除酸值后的皂化值为评价指标,研究了反应配比、反应温度、反应时间对合成油酸三乙醇胺皂化物的影响。结果表明,油酸和三乙醇胺配比为1.2∶1(mol /mol)、温度为130℃、反应时间为3h 时,反应达到平衡时体系中油酸三乙醇胺皂化物的含量最多。利用合成的油酸三乙醇胺皂化物调配成的水基润滑油符合相关要求。

  16. H{sub 3}PW{sub 12}O{sub 40} (HPA), an efficient and reusable catalyst for biodiesel production related reactions. Esterification of oleic acid and etherification of glycerol

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda, Jorge H.; Vera, Carlos R.; Yori, Juan C.; Badano, Juan M., E-mail: jsepulve@fiq.unl.edu.a [Instituto de Investigaciones en Catalisis y Petroquimica, Santiago del Estero Santa Fe (Argentina); Santarosa, Daniel; Mandelli, Dalmo [Pontificia Universidade Catolica de Campinas, SP (Brazil). Faculdade Quimica

    2011-07-01

    In esterification of oleic acid with methanol at 25 deg C HPA displayed the highest activity. Moreover the HPA could be reused after being transformed into its cesium salt. In the reaction of etherification of glycerol HPA and Amberlyst 35W showed similar initial activity levels. The results of acid properties demonstrate that HPA is a strong protonic acid and that both surface and bulk protons contribute to the acidity. Because of its strong affinity for polar compounds, HPA is also seemingly dissolved in both oleic acid and methanol. The reaction in this case proceeds with the catalyst in the homogenous phase. (author)

  17. Effect of partial liquid ventilation on lung function in oleic acid-induced lung injury model of piglets

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-zhuo; LI Ling-ke; ZHANG Yan-bo; LI Gang; XU Yu-lin; ZHU Yao-bin

    2013-01-01

    Background Pediatric patients are susceptible to lung injury that does not respond to traditional therapies.Partial liquid ventilation (PLV) has been developed as an alternative ventilatory strategy for treating severe lung injury.The aim of this study is to investigate the effect of PLV on lung function in immature piglets.Methods Acute lung injury was induced in 12 Chinese immature piglets by oleic acid (OA).The animals were randomly assigned to two groups (n=6 each group):(1) conventional mechanical ventilation (MV) group and (2) PLV with FC-77 (10 ml/kg) group.Mean arterial blood pressure (MAP),mean pulmonary arterial pressure (MPAP),central venous pressure (CVP),left atrial pressure (LAP),systemic vascular resistance (SVR),pulmonary vascular resistance (PVR),cardiac output (CO),mean pressure of airway (Paw),dynamic lung compliance (Cydn),and arterial blood gases were measured during the observation period.Results No piglet died in either group with severe lung injury.After four hours of ventilation,pH in the MV group gradually decreased to lower than 7.20,while in the PLV group,pH also gradually decreased but remained higher than 7.20 (P <0.05).Partial pressure of oxygen in artery (PaO2) decreased in both groups,but with a significant difference between the PLV group and MV group (P <0.05).Partial pressure of carbon dioxide in artery (PaCO2) increased in both groups,but with a significant difference between the PLV group and MV group (P <0.05).Paw increased in both groups,but was not significantly different (P >0.05).Cydn decreased in both groups,but without a significant difference (P >0.05).At four hours,heart rate (HR) and MAP in both groups decreased.MPAP in both groups increased,and there was a significant difference between the two groups (P <0.05).CVP was stable in both groups.At four hours,PVR and LAP were increased in both groups.CO was decreased in both groups (P <0.05).SVR was stable during the observation time.Conclusion PLV did not

  18. Effect of oleic acid-induced acute lung injury and conventional mechanical ventilation on renal function in piglets

    Institute of Scientific and Technical Information of China (English)

    LIU Ai-jun; LING Feng; LI Zhi-qiang; LI Xiao-feng; LIU Ying-long; DU Jie; HAN Ling

    2013-01-01

    Background Animal models that demonstrate changes of renal function in response to acute lung injury (ALl) and mechanical ventilation (MV) are few.The present study was performed to examine the effect of ALl induced by oleic acid (OA) in combination with conventional MV strategy on renal function in piglets.Methods Twelve Chinese mini-piglets were randomly divided into two groups:the OA group (n=6),animals were ventilated with a conventional MV strategy of 12 ml/kg and suffered an ALl induced by administration of OA,and the control group (n=6),animals were ventilated with a protective MV strategy of 6 ml/kg and received the same amount of sterile saline.Results Six hours after OA injection a severe lung injury and a mild-moderate degree of renal histopathological injury were seen,while no apparent histological abnormalities were observed in the control group.Although we observed an increase in the plasma concentrations of creatinine and urea after ALl,there was no significant difference compared with the control group.Plasma concentrations of neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C increased (5.6±1.3) and (7.4±1.5) times in the OA group compared to baseline values,and were significantly higher than the values in the control group.OA injection in combination with conventional MV strategy resulted in a dramatic aggravation of hemodynamic and blood gas exchange parameters,while these parameters remained stable during the experiment in the control group.The plasma expression of TNF-α and IL-6 in the OA group were significantly higher than that in the control group.Compared with high expression in the lung and renal tissue in the OA group,TNF-α and IL-6 were too low to be detected in the lung and renal tissue in the control group.Conclusions OA injection in combination with conventional MV strategy not only resulted in a severe lung injury but also an apparent renal injury.The potential mechanisms involved a cytokine response of TNF-α and

  19. Atrial natriuretic peptide attenuates inflammatory responses on oleic acid-induced acute lung injury model in rats

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; ZHANG Yan-bo; LIU Dong-hai; LI Xiao-feng; LIU Ai-jun; FAN Xiang-ming; QIAO Chen-hui

    2013-01-01

    Background An inflammatory response leading to organ dysfunction and failure continues to be a major problem after injury in many clinical conditions such as sepsis,severe burns,and trauma.It is increasingly recognized that atrial natriuretic peptide (ANP) possesses a broad range of biological activities,including effects on endothelial function and inflammation.A recent study has revealed that ANP exerts anti-inflammatory effects.In this study we tested the effects of human ANP (hANP) on lung injury in a model of oleic acid (OA)-induced acute lung injury (ALl) in rats.Methods Rats were randomly assigned to three groups (n=6 in each group).Rats in the control group received a 0.9% solution of NaCl (1 ml.kg1.h-1) by continuous intravenous infusion,after 30 minutes a 0.9% solution of NaCl (1 ml/kg) was injected intravenously,and then the 0.9% NaCl infusion was restarted.Rats in the ALl group received a 0.9% NaCl solution (1 ml·kg-1·h-1) intravenous infusion,after 30 minutes OA was injected intravenously (0.1 ml/kg),and then the 0.9% NaCl infusion was restarted.Rats in the hANP-treated ALI group received a hANP (0.1μg·kg-1·min-1) infusion,after 30 minutes OA was injected intravenously (0.1 ml/kg),and then the hANP infusion was restarted.The anti-inflammation effects of hANP were evaluated by histological examination and determination of serum cytokine levels.Results Serum intedeukin (IL)-1β,IL-6,IL-10 and tumor necrosis factor (TNF) α were increased in the ALI group at six hours.The levels of all factors were significantly lower in the hANP treated rats (P <0.005).Similarly,levels of IL-1β,IL-6,IL-10 and TNF-α were higher in the lung tissue in the ALI group at six hours.hANP treatment significantly reduced the levels of these factors in the lungs (P <0.005).Histological examination revealed marked reduction in interstitial congestion,edema,and inflammation.Conclusion hANP can attenuate inflammation in an OA-induced lung injury in rat model.

  20. Genetic, molecular and expression features of the Pervenets mutant leading to high oleic acid content of seed oil in sunflower

    Directory of Open Access Journals (Sweden)

    Lacombe Séverine

    2002-01-01

    Full Text Available Pervenets is a sunflower population that displays seed oil with a high oleic acid content [HOAC]. Our aim is to reconcile all the data gathered on this mutant in a unique explanatory mechanism. All Pervenets-derived [HOAC] lines display no accumulation or a very reduced accumulation of the DELTA12-desaturase transcript in the embryos during the stages for oil accumulation. They also carry oleHOS specific RFLP markers revealed by an DELTA12-desaturase cDNA used as a probe. The linoleic or [LO] genotypes do not carry this RFLP marker, but another allele: oleLOR (oleHL locus. Linkage disequilibrium between the oleHOS allele and [HOAC] was verified. We studied the mode of inheritance of [HOAC] in two segregating populations. A F2 progenies revealed one dominant allele for [HOAC] that co-segregated with the oleHOS allele showing that the Pervenets mutation and oleHOS were closely linked. F6 recombinant inbred lines, showed the [HOAC] trait due to two independent loci: the locus carrying the oleHOS allele and another locus sup. One allele, supole, at this second locus may suppress the effect of the oleHOS allele on the [HOAC] trait. Northern analyses performed on [HOAC] lines and F1 ([HOAC] x [LO] hybrids revealed under-accumulation of DELTA12-desaturase transcript. Thus Pervenets mutation acts in trans. The oleHOS genomic region that may carry the Pervenets mutation was cloned. A genomic library was constructed in lambdafixII with the DNA from the RHA345 [HOAC] line and screened with a DELTA12-desaturase cDNA as a probe. Two overlapping clones were entirely sequenced and revealed carrying a gene for an DELTA12-desaturase probably located in the RE. This corresponds to the invariant part of the oleHL locus. Another clone (11.1 probably carries DELTA12-desaturase repeated sequences that cause instability of the clone. We showed that the 11.1 clone carries most of cDNA sequence, but due to its organization it is not yet sequenced. A mutation mechanism

  1. 柱前皂化HPLC法测定不同产地桃仁中亚油酸和油酸的量%Determination of linolic acid and oleic acid in Persicae Semen from different habitats by precolumn saponification HPLC method

    Institute of Scientific and Technical Information of China (English)

    刘威; 张帅; 付小环; 李红娟; 萧伟

    2013-01-01

    目的 建立柱前皂化HPLC测定不同产地桃仁脂肪酸中亚油酸、油酸的测定方法,为有效控制和科学评价桃仁药材质量提供依据.方法 桃仁以0.5 mol/mL氢氧化钾乙醇溶液皂化提取亚油酸、油酸,利用HPLC测定桃仁中亚油酸、油酸的量.色谱柱:Waters-Symmetry-RP-C18 (250 mm×4.6 mm,5μm),流动相为乙腈-0.1%磷酸水溶液(92∶8),体积流量1.0 mg/mL,检测波长205 nm,柱温30℃.结果 亚油酸进样量在8.193 2~163.864 μg/mL具有良好的线性关系(r=0.999 7),平均回收率为97.3%,RSD为2.7%;油酸进样量26.4~528.0 μg/mL具有良好的线性关系(r=0.999 5),平均回收率为98.0%,RSD为2.3%.结论 本方法准确,重复性好,简便易行,适用于桃仁脂肪酸中亚油酸、油酸的同时测定.%Objective To develop a precolumn saponification HPLC method for determining linolic acid and oleic acid in Persicae Semen from different habitats and to provide the basis for controlling the herb quality quickly and accurately.Methods The linolic acid and oleic acid in Persicae Semen were saponified with 0.5 mol/mL KOH/EtOH as saponifier.HPLC method was used to determine the contents of linolic acid and oleic acid.The column was Waters-Symmetry-RP-C18 (250 mm × 4.6 mm,5 μm),the mobile phase consisted of acetonitrile-0.1% aqueous phosphoric acid (92:8); The flow rate was 1.0 mg/mL; The absorbance was monitored at 205 nm; The column temperature was 30 ℃.Results The calibration curves of linolic acid and oleic acid were in a good linearity over the ranges of 8.193 2-163.864 μg/mL (r =0.999 7) and 26.4-528.0 μg/mL (r =0.999 5),and the average recoveries of linolic acid and oleic acid were 97.3% and 98.0% with RSD values of 2.7% and 2.3%,respectively (n =6).Conclusion This method is simple,sensitive,and accurate,which is suitable for the simultaneous determination oflinolic acid and oleic acid in Persicae Semen.

  2. Coupling aerosol surface and bulk chemistry with a kinetic double layer model (K2-SUB: oxidation of oleic acid by ozone

    Directory of Open Access Journals (Sweden)

    C. Pfrang

    2010-05-01

    Full Text Available We present a kinetic double layer model coupling aerosol surface and bulk chemistry (K2-SUB based on the PRA framework of gas-particle interactions (Pöschl-Rudich-Ammann, 2007. K2-SUB is applied to a popular model system of atmospheric heterogeneous chemistry: the interaction of ozone with oleic acid. We show that our modelling approach allows de-convoluting surface and bulk processes, which has been a controversial topic and remains an important challenge for the understanding and description of atmospheric aerosol transformation. In particular, we demonstrate how a detailed treatment of adsorption and reaction at the surface can be coupled to a description of bulk reaction and transport that is consistent with traditional resistor model formulations.

    From literature data we have derived a consistent set of kinetic parameters that characterise mass transport and chemical reaction of ozone at the surface and in the bulk of oleic acid droplets. Due to the wide range of rate coefficients reported from different experimental studies, the exact proportions between surface and bulk reaction rates remain uncertain. Nevertheless, the model results suggest an important role of chemical reaction in the bulk and an approximate upper limit of ~10−11 cm2 s−1 for the surface reaction rate coefficient. Sensitivity studies show that the surface accommodation coefficient of the gas-phase reactant has a strong non-linear influence on both surface and bulk chemical reactions. We suggest that K2-SUB may be used to design, interpret and analyse future experiments for better discrimination between surface and bulk processes in the oleic acid-ozone system as well as in other heterogeneous reaction systems of atmospheric relevance.

  3. Acidities of Water and Methanol in Aqueous Solution and DMSO

    Science.gov (United States)

    Gao, Daqing

    2009-01-01

    The relative acidities of water and methanol have been a nagging issue. In gas phase, methanol is more acidic than water by 36.0 kJ/mol; however, in aqueous solution, the acidities of methanol and water are almost identical. The acidity of an acid in solution is determined by both the intrinsic gas-phase ionization Gibbs energy and the solvent…

  4. Hepatic-portal oleic acid inhibits feeding more potently than hepatic-portal caprylic acid in rats

    NARCIS (Netherlands)

    Jambor de Sousa, Ulrike L.; Benthem, Lambertus; Arsenijevic, Denis; Scheurink, Anton J. W.; Langhans, Wolfgang; Geary, Noni; Leonhardt, Monika; Geary, Nori

    2006-01-01

    In several human and animal studies, medium-chain triglycerides decreased food intake more than did long-chain triglycerides. It is possible that faster uptake and metabolism of medium-chain fatty acids in the liver is responsible for this difference. To test this hypothesis we compared the feeding

  5. Antioxidant Activities of Tannins to Oleic Acid%植物单宁对油酸抗氧化性研究

    Institute of Scientific and Technical Information of China (English)

    唐余玲; 刘会云; 孔佳超; 张振; 胡薇; 王茹

    2013-01-01

    以固载单宁皮粉(IT-HP)作为含单宁的成品革模型物,以油酸模拟皮革中的不饱和油脂类加脂剂,研究植物单宁对油酸的抗氧化性.系统研究了固载单宁皮粉中3种不同单宁对油酸的抗氧化作用,并优选抗氧化性最好的黑荆树单宁,考察了单宁用量、pH值和温度等条件对其抗氧化作用的影响.结果表明:3种单宁均具有良好的抑制油酸过氧化作用;抗油酸过氧化能力的强弱顺序为:黑荆树单宁>杨梅单宁>落叶松单宁;黑荆树单宁用量为20%时,抗氧化性最强;较高的pH值有利于黑荆树单宁的抗氧化作用;温度主要对油酸过氧化速度产生影响;在油酸过氧化反应初期,温度对黑荆树单宁抗氧化性的影响较小.%Tannin - immobilized hide powder (IT - HP) was employed as the leather model and oleic acid was used to mimic the unsaturated fat liquoring agent. The anti - oxidation for three kinds of tannins, black wattle tannin, bayberry tannin, and larch tannin, was investigated. The effects of tannin dosage, pH, and temperature on the anti - oxidation of black wattle tannin were studied in detail. Results show that all these three kinds of tannins have inhibition effect for oleic acid oxidation, with an anti -oxidation effect sequence of black wattle tannin > bayberry tannin > larch tannin. The anti - oxidation activity of black wattle tannin is found to increase with the increasing of tannin dosage. On the other hand, a higher pH is more propitious to anti - oxidation effect of black wattle tannin. Temperature mainly affects the oxidation rate of oleic acid, while it applies negligible impact to the anti - oxidation activity of the black wattle tannin in the initial stage of oleic acid oxidation.

  6. Canola Oil in Lactating Dairy Cow Diets Reduces Milk Saturated Fatty Acids and Improves Its Omega-3 and Oleic Fatty Acid Content.

    Science.gov (United States)

    Welter, Katiéli Caroline; Martins, Cristian Marlon de Magalhães Rodrigues; de Palma, André Soligo Vizeu; Martins, Mellory Martinson; Dos Reis, Bárbara Roqueto; Schmidt, Bárbara Laís Unglaube; Saran Netto, Arlindo

    2016-01-01

    To produce milk that is healthier for human consumption, the present study evaluated the effect of including canola oil in the diet of dairy cows on milk production and composition as well as the nutritional quality of this milk fat. Eighteen Holstein cows with an average daily milk yield of 22 (± 4) kg/d in the middle stage of lactation were used. The cows were distributed in 6 contemporary 3x3 Latin squares consisting of 3 periods and 3 treatments: control diet (without oil), 3% inclusion of canola oil in the diet and 6% inclusion of canola oil in the diet (dry matter basis). The inclusion of 6% canola oil in the diet of lactating cows linearly reduced the milk yield by 2.51 kg/d, short-chain fatty acids (FA) by 41.42%, medium chain FA by 27.32%, saturated FA by 20.24%, saturated/unsaturated FA ratio by 39.20%, omega-6/omega-3 ratio by 39.45%, and atherogenicity index by 48.36% compared with the control treatment. Moreover, with the 6% inclusion of canola oil in the diet of cows, there was an increase in the concentration of long chain FA by 45.91%, unsaturated FA by 34.08%, monounsaturated FA by 40.37%, polyunsaturated FA by 17.88%, milk concentration of omega-3 by 115%, rumenic acid (CLA) by 16.50%, oleic acid by 44.87% and h/H milk index by 94.44% compared with the control treatment. Thus, the inclusion of canola oil in the diet of lactating dairy cows makes the milk fatty acid profile nutritionally healthier for the human diet; however, the lactating performance of dairy cows is reduce.

  7. Antioxidative Activities of Both Oleic Acid and Camellia tenuifolia Seed Oil Are Regulated by the Transcription Factor DAF-16/FOXO in Caenorhabditis elegans

    Science.gov (United States)

    Wei, Chia-Cheng; Yen, Pei-Ling; Chang, Shang-Tzen; Cheng, Pei-Ling; Lo, Yi-Chen; Liao, Vivian Hsiu-Chuan

    2016-01-01

    Background Tea seed oil is a high quality edible oil, yet lacking sufficient scientific evidences to support the nutritional and medical purposes. We identified major and minor components in Camellia tenuifolia seed oil and investigated the antioxidative activity and its underlying mechanisms in Caenorhabditis elegans. Principal Findings The results showed that the major constitutes in C. tenuifolia seed oil were unsaturated fatty acids (~78.4%). Moreover, two minor compounds, β-amyrin and β-sitosterol, were identified and their antioxidative activity was examined. We found that oleic acid was the major constitute in C. tenuifolia seed oil and plays a key role in the antioxidative activity of C. tenuifolia seed oil in C. elegans. Conclusions This study found evidences that the transcription factor DAF-16/FOXO was involved in both oleic acid- and C. tenuifolia seed oil-mediated oxidative stress resistance in C. elegans. This study suggests the potential of C. tenuifolia seed oil as nutrient or functional foods. PMID:27275864

  8. Experimental investigation to effects of oleic acid and lauric acid on stabilization of magnetorheological fluids%采用油酸和月桂酸改进磁流变液稳定性的实验研究

    Institute of Scientific and Technical Information of China (English)

    熊晨熙; 彭向和; 易成建

    2011-01-01

    The effects of oleic acid and lauric acid on the stabilization of magnetorheological fluids(MRF) were investigated experimentally.Several groups of samples were prepared,with both lauric acid and oleic acid as additives.The variations of the zero-field viscosity,mechanical property and sedimentation rate of these samples against time were tested,and the effects of volume fractions of lauric acid,oleic acid and carbonyl iron on the stabilization and mechanical property of the MRF samples were studied.The results indicated that the proper addition of lauric acid and oleic acid could significantly improve the mechanical property of magnetorheological fluids.%鉴于油酸和月桂酸2种表面活性剂对磁流变液稳定性所起到的不同的作用,制备了若干种不同配比的以油酸和月桂酸共同添加的磁流变液,测量它们的零场粘度、力学性能和沉降率-时间曲线,研究了月桂酸、油酸和羰基铁粉3种成分的含量对于磁流变液稳定性和力学性能的影响。结果表明合理的添加油酸和月桂酸对于制备零场粘度小且稳定性优良的磁流变液具有显著的效果。

  9. Preparation of Solid Phase Microextraction (SPME) Probes through Polyaniline Multiwalled Carbon Nanotubes (PANI/MWCNTs) Coating for the Extraction of Palmitic Acid and Oleic Acid in Organic Solvents

    OpenAIRE

    Khajeamiri, Alireza

    2012-01-01

    A fiber coating from polyaniline (PANI) was electrochemically prepared and employed for Solid phase micreoextraction (SPME). The PANI film was directly electrodeposited on the platinum wire surface using cyclic voltametry (CV) technique. The same method was applied for the preparation of SPME fiber coated by polyaniline multiwalled carbon nanotubes (PANI/MWCNTs) composite. The concentration of sulfuric acid for electropolymerization was 0.1 M in the presence of 0.045 M aniline in aqueous solu...

  10. Production of oleic acid ethyl ester catalyzed by crude rice bran (Oryza sativa lipase in a modified fed-batch system: problem and its solution

    Directory of Open Access Journals (Sweden)

    Indro Prastowo

    2015-01-01

    Full Text Available A fed-batch system was modified for the enzymatic production of Oleic Acid Ethyl Ester (OAEE using rice bran (Oryza sativa lipase by retaining the substrate molar ratio (ethanol/oleic acid at 2.05: 1 during the reaction. It resulted in an increase in the ester conversion up to 76.8% in the first 6 h of the reaction, and then followed by a decrease from 76.8% to 22.9% in 6 h later. Meanwhile, the production of water in the reaction system also showed a similar trend to the trend of ester production. The water was hypothesized to lead lipase to reverse the reaction which resulted in a decrease in both (water and esters in the last 6 h of the reaction. In order to overcome the problem, zeolite powders (25 and 50 mg/ml were added into the reaction system at 5 h of the reaction. As the result, final ester conversions increased drastically up to 90 - 95.7% (1.17 – 1.24 times. The addition also proved a hypothesis that the water was involved in reducing the ester conversion in the last 6 h of the reaction. Thus, the combination was effective to produce the high final ester conversion.

  11. Chemical composition and oxidative status of tissues from Iberian pigs as affected by diets: extensive feeding v. oleic acid- and tocopherol-enriched mixed diets.

    Science.gov (United States)

    Ventanas, S; Tejeda, J F; Estévez, M

    2008-04-01

    The present work was intended to analyse the chemical composition and oxidative stability of the muscle biceps femoris and adipose tissues from Iberian pigs fed different finishing diets: free-range feeding on grass and acorns in a 'Montanera' traditional system (MON), fed in confinement with a mixed diet containing high-oleic sunflower oil (115 g/kg of diet) and supplemented with 250 mg/kg α-tocopherol (HOVE), and fed in confinement with a tocopherol-non-supplemented control mixed diet (CON). Muscles from MON pigs contained significantly (P < 0.05) higher amounts of intramuscular fat than those from HOVE and CON pigs. Muscles from MON and HOVE pigs had significantly higher levels of α-tocopherol than muscles from CON pigs whereas free-range feeding provided significantly higher levels of γ-tocopherol to muscles from MON pigs than the experimental diets did to CON and HOVE pigs. Adipose tissues from MON and HOVE pigs contained significantly lower proportions of saturated fatty acids and significantly higher levels of oleic acid and monounsaturated fatty acids than those from CON pigs. Tissues from MON pigs contained significantly smaller levels of polyunsaturated fatty acids than those from CON and HOVE pigs. To a higher extent, feeding background affected the fatty acid composition of polar lipids from the muscle biceps femoris than that of neutral lipids. Tissues from MON pigs contained significantly smaller ω-6/ω-3 values than those from pigs fed mixed diets. Compared to tissues from CON pigs, those from MON and HOVE pigs exhibited a higher oxidative stability as a likely result of a most favourable fatty acid composition and the presence of higher tocopherol levels.

  12. Trivalent chromium alleviates oleic acid induced steatosis in SMMC-7721 cells by decreasing fatty acid uptake and triglyceride synthesis.

    Science.gov (United States)

    Wang, Song; Wang, Jian; Zhang, Xiaonan; Hu, Linlin; Fang, Zhijia; Huang, Zhiwei; Shi, Ping

    2016-10-01

    Trivalent chromium [Cr(III)] has been shown as an essential trace element for human health. Previous studies depict that Cr(III) plays important roles in maintaining normal glucose and lipid metabolism, whereas its effect on the hepatic lipid metabolism is still unknown. In the present study, we investigated the effects and underlying mechanisms of Cr on hepatic steatosis induced by oleic acid (OA) in human hepatoma SMMC-7721 cells. Hepatic steatosis model was co-administered with Cr. Indexes of lipid accumulation were determined and associated genes expression were analyzed. The data showed that OA could induce lipid accumulation and triglyceride (TG) content in SMMC-7721 cells, and significantly increase the expression of cluster of differentiation 36 (CD36) and diacylglycerol acyltransferase 2 (DGAT2). This steatosis effect of OA was ameliorated by Cr. The TG accumulation and up-regulation of CD36 and DGAT2 genes followed steatosis induction were inhibited by Cr. After the treatment of Cr, excessive intracellular OA content was also attenuated. Furthermore, Cr still performed inhibitory effect of DGAT2 expression at the presence of DGAT2 agonist or inhibitor, which indicated that the inhibitory effect of Cr on lipogenesis is associated with the downregulation of DGAT2 expression. These findings demonstrate that Cr alleviates hepatic steatosis via suppressing CD36 expression to prevent fatty acid uptake, as well as suppressing DGAT2 expression to inhibit TG synthesis. It suggests that CD36 and DGAT2 might become the novel drug targets for their properties in hepatic steatosis. Most importantly, Cr may be a potential anti-steatosis candidate to offer protective effects against liver damage. PMID:27497686

  13. Thermochemistry of aqueous pyridine-3-carboxylic acid (nicotinic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Elsa M. [Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade de Lisboa, 1749-016 Lisboa (Portugal); Instituto Politecnico de Setubal, ESTBarreiro, Rua Americo da Silva Marinho, 2839-001 Lavradio (Portugal); Rego, Talita S. [Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade de Lisboa, 1749-016 Lisboa (Portugal); Minas da Piedade, Manuel E., E-mail: memp@fc.ul.p [Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade de Lisboa, 1749-016 Lisboa (Portugal)

    2011-06-15

    Research highlights: {yields} We determined the {Delta}{sub sol}H{sub m} of solid nicotinic acid (NA) in water by solution calorimetry. {yields} We determined {Delta}{sub dil}H{sub m} of an aqueous nicotinic acid solution by flow calorimetry. {yields} We determined (aq, {infinity}) for the 3 NA species involved in acid/base equilibria. {yields} We determined the enthalpy of formation of NA(aq) under saturation conditions.. - Abstract: The molar enthalpy of solution of solid nicotinic acid (NA) at T = 298.15 K, to give an aqueous solution of molality m = 3.748 . 10{sup -3} mol {center_dot} kg{sup -1}, was determined as {Delta}{sub sol}H{sub m} = (19,927 {+-} 48) J {center_dot} mol{sup -1}, by solution calorimetry. Enthalpies of dilution, {Delta}{sub dil}H{sub m}, of 0.1005 mol {center_dot} kg{sup -1} aqueous nicotinic acid to yield final solutions with molality in the approximate range (0.03 to 0.09) mol {center_dot} kg{sup -1} were also measured by flow calorimetry. Combining the two sets of data and the results of pH measurements, with values of proton dissociation enthalpies and {Delta}{sub f}H{sub m}{sup 0}(NA, cr) selected from the literature, it was possible to derive the standard molar enthalpies of formation of the three nicotinic acid species involved in protonation/deprotonation equilibria, at infinite dilution: {Delta}{sub f}H{sub m}{sup 0}(HN{sup +}C{sub 5}H{sub 4}COOH.{infinity}H{sub 2}O,aq) = (328.2 {+-} 1.2) kJ {center_dot} mol{sup -1}, {Delta}{sub f}H{sub m}{sup 0}(HN{sup +}C{sub 5}H{sub 4}COO{sup -}.{infinity}H{sub 2}O,aq) = (325.0 {+-} 1.2) kJ {center_dot} mol{sup -1}, and {Delta}{sub f}H{sub m}{sup 0}(NC{sub 5}H{sub 4}COO{sup -}.{infinity}H{sub 2}O,aq) = (313.7 {+-} 1.2) kJ {center_dot} mol{sup -1}. Finally, the enthalpy of solution of nicotinic acid at T = 298.15 K, under saturation conditions (m = 0.138 mol {center_dot} kg{sup -1}), and the standard molar enthalpy of formation of the corresponding solution could also be obtained as {Delta

  14. Preparation and characterization of alumina supported nickel-oxalate catalyst for the hydrodeoxygenation of oleic acid into normal and iso-octadecane biofuel

    International Nuclear Information System (INIS)

    Highlights: • Preparation of nickel oxalate complex as catalyst precursor. • Incorporation of nickel oxalate complex into alumina support. • Characterization of the alumina supported nickel oxalate catalyst. • Hydrodeoxygenation of oleic acid with nickel oxalate catalyst. • Nickel oxalate catalyst reusability studies. - Abstract: In this study, nickel II oxalate complex (NiOx) was prepared by functionalization of nickel with oxalic acid (OxA) and incorporated into Al2O3 to synthesize alumina supported nickel oxalate (NiOx/Al2O3) catalyst for the hydrodeoxygenation (HDO) of oleic acid (OA) into biofuel. The synthesized NiOx/Al2O3 was characterized and the X-ray fluorescence and elemental dispersive X-ray results showed that NiOx was successfully incorporated into the structure of Al2O3. The X-ray diffraction and Raman spectroscopy results confirmed that highly dispersed Ni species are present in the NiOx/Al2O3 due to the functionalization with OxA. The catalytic activity of the NiOx/Al2O3 on the HDO of OA produced a mixture of 21% iso-C18 and 72% n-C18 at a 360 °C, 20 bar, 30 mg NiOx/Al2O3 loading pressure and gas flow rate of 100 mL/min. The presence of i-C18 was ascribed to the OxA functionalization which increased the acidity of NiOx/Al2O3. The NiOx/Al2O3 reusability study showed consistent HDO ability after 5 runs. These results are promising for further research into biofuel production for commercialization

  15. Spin-dependent transport properties of oleic acid molecule self-assembled La{sub 0.7}Sr{sub 0.3}MnO{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Xi, L., E-mail: xili@lzu.edu.cn [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Du, J.H.; Ma, J.H.; Wang, Z.; Zuo, Y.L.; Xue, D.S. [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2013-02-15

    Highlights: Black-Right-Pointing-Pointer Spin-dependent transport property of LSMO/oleic acid nanoparticles is investigated. Black-Right-Pointing-Pointer Transport properties and MR measured by Cu/nanoparticle assembly/elargol device. Black-Right-Pointing-Pointer Non-linear I-V curve indicates a tunneling type transport properties. Black-Right-Pointing-Pointer Tunnel barrier height around 1.3 {+-} 0.15 eV was obtained by fitting I-V curves. Black-Right-Pointing-Pointer LFMR of LSMO/oleic acid molecules value reaches -18% with current of 0.1 {mu}A at 10 K. - Abstract: Spin-dependent transport property through molecules is investigated using a monolayer of oleic acid molecule self-assembled half metallic La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) nanoparticles, which was synthesized using a coprecipitation method. Fourier transform infrared spectroscopy was used to confirm that one-monolayer oleic acid molecules chemically bond to the LSMO nanoparticles. The transport properties and magnetoresistance (MR) effect of the oleic acid molecule coated LSMO nanoparticles were measured by a direct current four probes method using a Cu/nanoparticle assembly/elargol electrode sandwich device with various temperatures and bias voltages. The non-linear I-V curve indicates a tunneling type transport properties. The tunnel barrier height around 1.3 {+-} 0.15 eV was obtained by fitting the I-V curve according to the Simmons equation. The magnetoresistance curves can be divided to high-field MR and low-field MR (LFMR) parts. The former is ascribed to the influence of spin disorder or canting within the LSMO nanoparticle surface and the latter one with strong bias dependence is attributed to the spin-dependent tunneling effect through the insulating surface layer of LSMO and oleic acid molecules. The enhanced LFMR effect for oleic acid coated LSMO with respect to the bare LSMO was attributed to the enhanced tunneling transport and weak spin scattering in oleic acid molecule barrier.

  16. Nitro-Oleic Acid Reduces J774A.1 Macrophage Oxidative Status and Triglyceride Mass: Involvement of Paraoxonase2 and Triglyceride Metabolizing Enzymes.

    Science.gov (United States)

    Rosenblat, Mira; Rom, Oren; Volkova, Nina; Aviram, Michael

    2016-08-01

    Nitro-fatty acids possess anti-atherogenic properties, but their effects on macrophage oxidative status and lipid metabolism that play important roles in atherosclerosis development are unclear. This study compared the effects of nitro-oleic acid (OLA-NO2) with those of native oleic acid (OLA) on intracellular reactive oxygen species (ROS) generation, anti-oxidants and metabolism of triglycerides and cholesterol in J774A.1 macrophages. Upon incubating the cells with physiological concentrations of OLA-NO2 (0-1 µM) or with equivalent levels of OLA, ROS levels measured by 2, 7-dichlorofluorescein diacetate, decreased dose-dependently, but the anti-oxidative effects of OLA-NO2 were significantly augmented. Copper ion addition increased ROS generation in OLA treated macrophages without affecting OLA-NO2 treated cells. These effects could be attributed to elevated glutathione levels and to increased activity and expression of paraoxonase2 that were observed in OLA-NO2 vs OLA treated cells. Beneficial effects on triglyceride metabolism were noted in OLA-NO2 vs OLA treated macrophages in which cellular triglycerides were reduced due to attenuated biosynthesis and accelerated hydrolysis of triglycerides. Accordingly, OLA-NO2 treated cells demonstrated down-regulation of diacylglycerol acyltransferase1, the key enzyme in triglyceride biosynthesis, and increased expression of hormone-sensitive lipase and adipose triglyceride lipase that regulate triglyceride hydrolysis. Finally, OLA-NO2 vs OLA treatment resulted in modest but significant beneficial effects on macrophage cholesterol metabolism, reducing cholesterol biosynthesis rate and low density lipoprotein influx into the cells, while increasing high density lipoprotein-mediated cholesterol efflux from the macrophages. Collectively, compared with OLA, OLA-NO2 modestly but significantly reduces macrophage oxidative status and cellular triglyceride content via modulation of cellular anti-oxidants and triglyceride

  17. Nitro-Oleic Acid Reduces J774A.1 Macrophage Oxidative Status and Triglyceride Mass: Involvement of Paraoxonase2 and Triglyceride Metabolizing Enzymes.

    Science.gov (United States)

    Rosenblat, Mira; Rom, Oren; Volkova, Nina; Aviram, Michael

    2016-08-01

    Nitro-fatty acids possess anti-atherogenic properties, but their effects on macrophage oxidative status and lipid metabolism that play important roles in atherosclerosis development are unclear. This study compared the effects of nitro-oleic acid (OLA-NO2) with those of native oleic acid (OLA) on intracellular reactive oxygen species (ROS) generation, anti-oxidants and metabolism of triglycerides and cholesterol in J774A.1 macrophages. Upon incubating the cells with physiological concentrations of OLA-NO2 (0-1 µM) or with equivalent levels of OLA, ROS levels measured by 2, 7-dichlorofluorescein diacetate, decreased dose-dependently, but the anti-oxidative effects of OLA-NO2 were significantly augmented. Copper ion addition increased ROS generation in OLA treated macrophages without affecting OLA-NO2 treated cells. These effects could be attributed to elevated glutathione levels and to increased activity and expression of paraoxonase2 that were observed in OLA-NO2 vs OLA treated cells. Beneficial effects on triglyceride metabolism were noted in OLA-NO2 vs OLA treated macrophages in which cellular triglycerides were reduced due to attenuated biosynthesis and accelerated hydrolysis of triglycerides. Accordingly, OLA-NO2 treated cells demonstrated down-regulation of diacylglycerol acyltransferase1, the key enzyme in triglyceride biosynthesis, and increased expression of hormone-sensitive lipase and adipose triglyceride lipase that regulate triglyceride hydrolysis. Finally, OLA-NO2 vs OLA treatment resulted in modest but significant beneficial effects on macrophage cholesterol metabolism, reducing cholesterol biosynthesis rate and low density lipoprotein influx into the cells, while increasing high density lipoprotein-mediated cholesterol efflux from the macrophages. Collectively, compared with OLA, OLA-NO2 modestly but significantly reduces macrophage oxidative status and cellular triglyceride content via modulation of cellular anti-oxidants and triglyceride

  18. Quantitative Analysis of α-Linolenic Acid, Linoleic Acid and Oleic Acid in Guizhi Fuling Capsules%桂枝茯苓胶囊中α-亚麻酸、亚油酸和油酸的含量分析

    Institute of Scientific and Technical Information of China (English)

    尹权微; 王金玲; 杨素德; 黄文哲; 萧伟

    2016-01-01

    目的:建立同时测定桂枝茯苓胶囊中α-亚麻酸、亚油酸和油酸含量的高效液相色谱方法。方法:采用Waters Symmetry C18(250 mm×4.6 mm,5μm)色谱柱;以乙腈-0.1%磷酸为流动相,进行梯度洗脱;流速1.0 mL·min-1;柱温30℃;检测波长205 nm。结果:α-亚麻酸在0.66~10.50μg·mL-1(r=0.9998),亚油酸在6.31~100.92μg·mL-1(r=0.9997),油酸在5.00~79.92μg·mL-1(r=1.0)范围内呈良好的线性关系;平均加样回收率:α-亚麻酸为97.02%,RSD为0.88%;亚油酸为97.17%,RSD为0.80%;油酸为96.98%,RSD为0.78%(n=6)。结论:该方法进样精密度、重复性、溶液稳定性均良好,适合于测定桂枝茯苓胶囊中的活性成分,为质量控制提供参考。%Objective: To establish an HPLC method for the determination of α-linolenic acid, linoleic acid and oleic acid in Guizhi Fuling capsules. Methods: The Waters C18 (250 mm×4.6 mm, 5μm) column was applied with a mobile phase of acetonitrile-0.1% phosphoric acid (80∶20), the flow rate was 1.0 mL· min-1, the column temperature was 30℃, the detection wavelength was 205 nm. Results: The linear ranges of α-linolenic acid, linoleic acid and oleic acid were 0.66-10.50μg·mL-1 (r=0.9998), 6.31-100.92μg·mL-1 (r=0.9997) and 5.00-79.92μg·mL-1 (r=1.0), respectively. The average recoveries were 97.02% with RSD 0.88% for α-Linoleic acid, 97.17%, with RSD 0.80% for linoleic acid and 96.98% with RSD 0.78% for oleic acid (n=6). Conclusion: The method can be used to control the quality of α-linoleic acid, linoleic acid and oleic acid in Guizhi Fuling capsule, which is simple, accurate, convenient, specific and repeat-able.

  19. Ionisation constants of inorganic acids and bases in aqueous solution

    CERN Document Server

    Perrin, D D

    2013-01-01

    Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution, Second Edition provides a compilation of tables that summarize relevant data recorded in the literature up to the end of 1980 for the ionization constants of inorganic acids and bases in aqueous solution. This book includes references to acidity functions for strong acids and bases, as well as details about the formation of polynuclear species. This text then explains the details of each column of the tables, wherein column 1 gives the name of the substance and the negative logarithm of the ionization constant and column 2

  20. Effect of oleic acid on the production of ethanol and fructose from glucose/fructose mixtures in an immobilized cell reactor

    Energy Technology Data Exchange (ETDEWEB)

    Guenette, M.E. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering]|[IOGEN Corp., Ottawa, ON (Canada); Duvnjak, Z. [Ottawa Univ., ON (Canada). Dept. of Chemical Engineering]|[IOGEN Corp., Ottawa, ON (Canada)

    1995-12-31

    Saccharomyces cerevisiae ATCC 39859 was immobilized onto small cubes of wood to produce ethanol and very enriched fructose syrup from glucose/fructose mixtures through the selective fermentation of glucose. A maximum ethanol productivity of 21.9 g/l.h was attained from a feed containing 9.7% (w/v) glucose and 9.9% (w/v) fructose. An ethanol concentration, glucose conversion and fructose yield of 29.6 g/l, 62% and 99% were obtained, respectively. This resulted in a final fructose/glucose ratio of 2.7. At lower ethanol productivity levels the fructose/glucose ratio increases, as does the ethanol concentration in the effluent. The addition of 30 mg/l oleic acid to the medium increased the ethanol productivity and its concentration by 13% at a dilution rate of 0.74 h{sup -1}. (orig.)

  1. Effect of the distribution of saturated fatty acids in the melting and crystallization profiles of high-oleic high-stearic oils

    Directory of Open Access Journals (Sweden)

    Bootello, M. A.

    2016-09-01

    Full Text Available The composition and distribution of fatty acids in triacylglycerol (TAG molecules are commonly considered as factors that determine the physical properties of a given oil or fat. The distribution of any fatty acid in fats and oils can be described through the α coefficient of asymmetry, which can be calculated from the TAG composition and fatty acid composition of the sn-2 position of the TAGs determined through lipase hydrolysis. High-oleic high-stearic oils and fats are considered stable and healthy, and they are good substitutes for hydrogenated vegetable oils and palm fractions in many food products, such as spreads and confectionery. Here, different high-oleic high-stearic acid oils were formulated which contained different distributions of saturated fatty acids in their TAGs, while maintaining a similar fatty acid composition. The aim of this work was to discuss the possibility of using the α coefficient to predict the physical properties of fats in function of their chemical composition and their melting and crystallization behavior as examined by differential scanning calorimetry.La composición y distribución de los ácidos grasos en las moléculas de triglicéridos se consideran factores determinantes en las propiedades físicas de los aceites y grasas. La distribución de ácidos grasos en un determinado aceite o grasa puede caracterizarse mediante un coeficiente de asimetría α, calculado a partir de las composiciones de triglicéridos y de ácidos grasos en la posición sn-2 de la molécula de triglicérido mediante hidrólisis con lipasa. El aceite de girasol alto oleico-alto esteárico es una grasa estable y saludable, adecuada para reemplazar a los aceites vegetales hidrogenados y fracciones de palma en muchos productos alimentarios, como grasas plásticas y grasas de confitería. En el presente trabajo, se formularon diferentes aceites alto oleico-alto esteárico con diferente distribución de los ácidos grasos saturados en

  2. Photolysis of Periodate and Periodic Acid in Aqueous Solution

    DEFF Research Database (Denmark)

    Sehested, Knud; Kläning, U. K.

    1978-01-01

    The photochemistry of periodate and periodic acid in aqueous solution was studied (i) by quantum yield measurements at low light intensity (ii) by flash photolysis, and (iii) by photolysis of glassy samples at 77 K. The photochemical studies were supplemented with pulse radiolysis studies...... of aqueous periodate solutions and with kinetic studies using stopped-flow technique. In strongly alkaline solution the photodecomposition of periodate proceeds via formation of O– and IVI. At pH

  3. Decomposition Studies of Triphenylboron, Diphenylborinic Acid and Phenylboric Acid in Aqueous Alkaline Solutions Containing Copper

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C.L. [Westinghouse Savannah River Company, AIKEN, SC (United States); Peterson, R. A.

    1997-02-11

    This report documents the copper-catalyzed chemical kinetics of triphenylboron, diphenylborinic acid and phenylboric acid (3PB, 2PB and PBA) in aqueous alkaline solution contained in carbon-steel vessels between 40 and 70 degrees C.

  4. Oleic Acid Increases Synthesis and Secretion of VEGF in Rat Vascular Smooth Muscle Cells: Role of Oxidative Stress and Impairment in Obesity

    Directory of Open Access Journals (Sweden)

    Mariella Trovati

    2013-09-01

    Full Text Available Obesity is characterized by poor collateral vessel formation, a process involving vascular endothelial growth factor (VEGF action on vascular smooth muscle cells (VSMC. Free fatty acids are involved in the pathogenesis of obesity vascular complications, and we have aimed to clarify whether oleic acid (OA enhances VEGF synthesis/secretion in VSMC, and whether this effect is impaired in obesity. In cultured aortic VSMC from lean and obese Zucker rats (LZR and OZR, respectively we measured the influence of OA on VEGF-A synthesis/secretion, signaling molecules and reactive oxygen species (ROS. In VSMC from LZR we found the following: (a OA increases VEGF-A synthesis/secretion by a mechanism blunted by inhibitors of Akt, mTOR, ERK-1/2, PKC-beta, NADPH-oxidase and mitochondrial electron transport chain complex; (b OA activates the above mentioned signaling pathways and increases ROS; (c OA-induced activation of PKC-beta enhances oxidative stress, which activates signaling pathways responsible for the increased VEGF synthesis/secretion. In VSMC from OZR, which present enhanced baseline oxidative stress, the above mentioned actions of OA on VEGF-A, signaling pathways and ROS are impaired: this impairment is reproduced in VSMC from LZR by incubation with hydrogen peroxide. Thus, in OZR chronically elevated oxidative stress causes a resistance to the action on VEGF that OA exerts in LZR by increasing ROS.

  5. Raman spectra of amino acids and their aqueous solutions

    Science.gov (United States)

    Zhu, Guangyong; Zhu, Xian; Fan, Qi; Wan, Xueliang

    2011-03-01

    Amino acids are the basic "building blocks" that combine to form proteins and play an important physiological role in all life-forms. Amino acids can be used as models for the examination of the importance of intermolecular bonding in life processes. Raman spectra serve to obtain information regarding molecular conformation, giving valuable insights into the topology of more complex molecules (peptides and proteins). In this paper, amino acids and their aqueous solution have been studied by Raman spectroscopy. Comparisons of certain values for these frequencies in amino acids and their aqueous solutions are given. Spectra of solids when compared to those of the solute in solution are invariably much more complex and almost always sharper. We present a collection of Raman spectra of 18 kinds of amino acids ( L-alanine, L-arginine, L-aspartic acid, cystine, L-glutamic acid, L-glycine, L-histidine, L-isoluecine, L-leucine, L-lysine, L-phenylalanine, L-methionone, L-proline, L-serine, L-threonine, L-tryptophan, L-tyrosine, L-valine) and their aqueous solutions that can serve as references for the interpretation of Raman spectra of proteins and biological materials.

  6. Conductivity of Oxalic Acid in Aqueous Solution at Low Concentration

    Institute of Scientific and Technical Information of China (English)

    倪良; 韩世钧

    2005-01-01

    Oxalic acid is a weak and unsymmetrical bi-basic acid. There exist dissociation and association equilibria among the species in aqueous solution. The molar conductivity of the solution is the sum of the ionic contributions.Based on this idea, a new prediction equation of ionic conductivity was proposed at low concentration. The molar conductivities of the solution and its relevant ions were calculated respectively. The results obtained were in good agreement with those from experiments and the Quint-Viallard equation.

  7. Partial liquid ventilation decreases tissue and serum tumor necrosis factor-α concentrations in acute lung injury model of immature piglet induced by oleic acid

    Institute of Scientific and Technical Information of China (English)

    ZHU Yao-bin; FAN Xiang-ming; LI Xiao-feng; LI Zhi-qiang; WANG Qiang; SUN Li-zhong; LIU Ying-long

    2012-01-01

    Background Pediatric patients are susceptible to lung injury.Acute lung injury in children often results in high mortality.Partial liquid ventilation (PLV) has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury models.This study was designed to examine the hypothesis that PLV would attenuate the production of local and systemic tumor necrosis factor (TNF)-α in an immature piglet model of acute lung injury induced by oleic acid (OA).Methods Twelve Chinese immature piglets were induced acute lung injury by OA.The animals were randomly assigned to two groups of six animals,(1) conventional mechanical ventilation (MV) group and (2) PLV with 10 ml/kg FC-77 group.Results Compared with MV group,the PLV group had better cardiopulmonary variables (P <0.05).These variables included heart rate,mean blood pressure,blood pH,partial pressure of arterial oxygen (PaO2),PaO2/inspired O2 fraction (FiO2) and partial pressure of arterial carbon dioxide (PaCO2).PLV reduced TNF-α levels both in plasma and tissue compared with MV group (P <0.05).Conclusion PLV provides protective effects against TNF-a response in OA-induced acute lung injury in immature piglets.

  8. Heat transfer behaviour of silver particles containing oleic acid surfactant: application in a two phase closed rectangular cross sectional thermosyphon (RTPTC)

    Science.gov (United States)

    Bhuwakietkumjohn, N.; Parametthanuwat, T.

    2016-03-01

    This article focuses on heat transfer behaviour of silver nanoparticles containing oleic acid surfactant (OA) applied as a working fluid in a two-phase closed rectangular cross sectional thermosyphon (RTPTC). Thus, the OA could reduce the surface tension of the working fluid, which improved the colloidal ability and increased the lead-time period for nanoparticles to be uniformly dispersed. It highlights theories for investigating the effects on heat transfer characteristics of RTPTC such as heat transfer rate, thermal resistance, heat transfer coefficients and nanofluids behaviour. The most important heat transfer characteristic to be examined in this experiment is the relative thermal efficiency (R T ). Five working fluids were tested, these include: de-ionized water; de-ionized water base with a silver nanoparticles concentration of 0.5 wt% (NP); and NP containing 0.5; 1; and 1.5 wt% of OA respectively. The results showed that 0.5 wt% NP containing 1 wt% OA produced the best results. It was further found that the heat transfer rate of 0.5 wt% NP containing 1 wt% of OA with a R T value of 1, was the highest across all experimental parameters studied. The NP containing OA demonstrated approximately 80 % higher heat transfer rate than the de-ionized water.

  9. Black beams (Phaseolus vulgaris) diets' effects heating in different ways and times with or without methionine addition, in growth, liver and mice thyroid, using oleic acid 125 I

    International Nuclear Information System (INIS)

    Weanling rats were divided into 13 groups of six animals and were fed 'ad libitum' for four weeks with diets containing casein as protein source for the control group and bean cooked in an autoclave at 1200 C for 30, 45 and 60 minutes or cooked in an ordinary pot for 60, 120 and 180 minutes, with and without addition of methionine. Oleic acid 125 l, mixed with other nutrients, was added to the diets in order to study the distribution of radioactivity in the animal body and its excretion. The influence of heating the beans by different ways and times, with and without addition of methionine, on the growth of the animals was verified by means of the gain in weight, food efficiency ratio (FER) and protein efficiency ratio (PER). Studies in animal feces, urine and carcass were carried out. The quantity of lipids in the feces and carcass was determined. The influence of the diets on the liver and thyroid was verified by means of their weights and the quantity of radioactivity in these organs. (author)

  10. Modification of the hydrophilic/hydrophobic characteristic of zein film surfaces by contact with oxygen plasma treated PDMS and oleic acid content.

    Science.gov (United States)

    Gezer, P Gizem; Brodsky, Serena; Hsiao, Austin; Liu, G Logan; Kokini, Jozef L

    2015-11-01

    Zein has been widely studied as a biopolymer due to its unique film-forming abilities. Surface properties are of high importance for certain applications which include microfluidics and tissue engineering, as they drastically affect the end result. It is important to develop techniques to modify zein surface properties without compromising bulk material properties. In this study, we developed a facile technique to change the water affinity of zein film surfaces, compatible with patterning techniques via soft lithography. This is achieved by a simple solvent casting technique onto a polydimethylsilohexane (PDMS) substrate that was exposed to oxygen plasma. Water contact angle measurements (WCA) were used to assess the hydrophillicity of zein surfaces and they reached as low as 20°. Atomic force microscopy, optical absorbance and light microscopy were used to study the characteristics of the film and its surface topography. Hydrophilic zein surfaces had higher roughness values compared to hydrophobic ones. Surface roughness, introduced by sandpaper and gratings does not have the same effect as surface chemistry. The amphiphilic nature of plasticizer oleic acid also contributed to the change in the water contact angle of the films. In conclusion, we demonstrated that zein film's surface properties can be controlled by its ability to self-assemble depending on the substrate that it is being cast on.

  11. γ-Irradiation of malic acid in aqueous solutions

    Science.gov (United States)

    Negron-Mendoza, Alicia; Graff, Rebecca L.; Ponnamperuma, Cyril

    1980-12-01

    The γ-irradiation of malic acid in aqueous solutions was studied under initially oxygenated and oxygen-free conditions in an attempt to determine the possible interconversion of malic acid into other carboxylic acids, specifically those associated with Krebs cycle. The effect of dose on product formation of the system was investigated. Gas-liquid chromatography combined with mass spectrometry was used as the principal means of identification of the non-volatile products. Thin layer chromotography and direct probe mass spectroscopy were also employed. The findings show that a variety of carboxylic acids are formed, with malonic and succinic acids in greatest abundance. These products have all been identified as being formed in the γ-irradiation of acetic acid, suggesting a common intermediary. Since these molecules fit into a metabolic cycle, it is strongly suggestive that prebiotic pathways provided the basis for biological systems.

  12. Gamma-irradiation of malic acid in aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Negron-Mendoza, A.; Graff, R.L.; Ponnamperuma, C.

    1980-12-01

    The gamma-irradiation of malic acid in aqueous solutions was studied under initially oxygenated and oxygen-free conditions in an attempt to determine the possible interconversion of malic acid into other carboxylic acids, specifically those associated with Krebs cycle. The effect of dose on product formation of the system was investigated. Gas-liquid chromatography combined with mass spectrometry was used as the principal means of identification of the nonvolatile products. Thin layer chromatography and direct probe mass spectroscopy were also employed. The findings show that a variety of carboxylic acids are formed, with malonic and succinic acids in greatest abundance. These products have all been identified as being formed in the gamma-irradiation of acetic acid, suggesting a common intermediary. Since these molecules fit into a metabolic cycle, it is strongly suggestive that prebiotic pathways provided the basis for biological systems.

  13. 高油酸油菜研究现状、存在的问题及发展建议%Present Research Situation,Questions and Developmental Advises of High Oleic Acid Rapeseed

    Institute of Scientific and Technical Information of China (English)

    张振乾; 胡庆一; 官春云

    2016-01-01

    High oleic acid rapeseed oil has very good nutrition and health functions,and its quality can be comparable with the camellia oil,olive oil and other senior edible vegetable oil,which is helpful to increase the edible vegetable oil supply of China and promote the upgrading of the rape industry. The study trend and application situation of Hunan Agricultural Uni-versity and the other domestic and foreign research institutions were summarized in this paper. At the same time,the genetic characteristics of oleic acid,high oleic acid rapeseed breeding (microspore culture,distant hybridization,induced and transgenic technology),advances of high oleic acid rapeseed breeding by different methods (such as,microspore culture, distant hybridization,mutation and transgenic technology),and the molecular biology research were summarized. In addi-tion,several advices were proposed according to the currently existing questions.%高油酸菜油具有很好的营养保健功能,其品质可与茶油、橄榄油等高级食用植物油媲美,对于改变我国食用植物油自给不足、促进油菜产业升级等方面有很好的作用。总结了国内外相关研究机构在高油酸油菜方面的研究动态及应用情况,同时对油酸的遗传特性、高油酸油菜选育途径(小孢子培养、远缘杂交、诱变和转基因技术)和分子生物学研究进展进行了综述,并针对当前存在的问题提出了一些建议。

  14. Effects of butter oil blends with increased concentrations of stearic, oleic and linolenic acid on blood lipids in young adults

    DEFF Research Database (Denmark)

    Becker, Claus; Lund, Pia; Hølmer, Gunhild Kofoed;

    1999-01-01

    healthy free-living young men (age 21-26 y) fulfilled the study. INTERVENTIONS: At thebeginning and end of each diet period two venous blood samples were collected. Triacylglycerol and cholesterolconcentrations in total plasma and VLDL, LDL, IDL and HDL fractions were measured, as were apo A-1 and apo...... Bconcentrations. Fatty acid composition of plasma phospholipids, plasma cholesterol ester and platelets was alsodetermined. RESULTS: Significantly (P LDL-cholesterol concentrations were observed after theBR and BS period, compared to BG. The effect of BR and BS did not differ. BG and BR...... resulted in equalconcentrations of HDL-C, but significantly higher than BS. Consequently, a significantly lower LDL-C/HDL-C ratio wasseen after the BR treatment compared to BG and BS. Apo A-1 concentrations were not significantly different, but ApoB was significantly increased after BG. CONCLUSIONS...

  15. Oleic and linoleic acids are active principles in Nigella sativa and stabilize an E2P conformation of the Na,K-ATPase. Fatty acids differentially regulate cardiac glycoside interaction with the pump

    DEFF Research Database (Denmark)

    Mahmmoud, Yasser Ahmed; Christensen, Søren Brøgger

    2011-01-01

    Nigella sativa seed oil was found to contain a modulator of Na,K-ATPase. Separation analyses combined with (1)H NMR and GCMS identified the inhibitory fraction as a mixture of oleic and linoleic acids. These two fatty acids are specifically concentrated in several medicinal plant oils, and have...... particularly been implicated in decreasing high blood pressure. The ouabain binding site on Na,K-ATPase has also been implicated in blood pressure regulation. Thus, we aimed to determine how these two molecules modify pig kidney Na,K-ATPase. Oleic and linoleic acids did not modify reactions involving the E(1......) (Na(+)) conformations of the Na,K-ATPase. In contrast, K(+) dependent reactions were strongly modified after treatment. Oleic and linoleic acids were found to stabilize a pump conformation that binds ouabain with high affinity, i.e., an ion free E(2)P form. Time-resolved binding assays using...

  16. Amino Acids Catalyzed Direct Aldol Reactions in Aqueous Micelles

    Institute of Scientific and Technical Information of China (English)

    PENG Yi-Yuan; WANG Qi; DING Qiu-Ping; HE Jia-Qi; CHENG Jin-Pei

    2003-01-01

    @@ Since the discovery of its roles as a good small-organic-molecule catalyst in intramolecular aldol reactions, pro line has drawn considerable attention in synthetic chemistry due to its similarity to the type-Ⅰ aldolases. Recently,List and others have reported some new direct asymmetric intermolecular reactions catalyzed by proline, including aldol, Mannich, Michael, and other analogous reactions. Except for two recent examples, [1,2] proline catalyzed aldol reactions in aqueous micelles have not been reported, nor have other amino acids as organocatalysts in directly catalyzing aldol reaction been reported. Herein we wish to present our recent results regarding environmentally be nign direct aldol reactions catalyzed by amino acids including proline, histidine and arginine in aqueous media.

  17. Pulse Radiolysis of Adrenaline in Acid Aqueous Solutions

    DEFF Research Database (Denmark)

    Gohn, M.; Getoff, N.; Bjergbakke, Erling

    1976-01-01

    Pulse radiolysis of adrenaline in acid aqueous solutions (pH 1–3) was carried out. The rate constants for the reactions of adrenaline with H and OH were determined: k(H + adr.) = (0·9±0·1) × 109 dm3 mol−1s−1; k(OH + adr.) = (1·65±0·15) × 1010 dm3 mol−1s−1. The H-adduct of adrenaline has two λmax...

  18. Parallel proton transfer pathways in aqueous acid-base reactions

    OpenAIRE

    Cox, M. J.; Bakker, H.J.

    2008-01-01

    We study the mechanism of proton transfer (PT) between the photoacid 8-hydroxy-1,3, 6-pyrenetrisulfonic acid (HPTS) and the base chloroacetate in aqueous solution. We investigate both proton and deuteron transfer reactions in solutions with base concentrations ranging from 0.25M to 4M. Using femtosecond midinfrared spectroscopy, we probe the vibrational responses of HPTS, its conjugate photobase, the hydrated proton/deuteron, and chloroacetate. The measurement of these four resonances allows ...

  19. Activation of SUR2B/Kir6.1-type KATP channels protects glomerular endothelial, mesangial and tubular epithelial cells against oleic acid renal damage

    Institute of Scientific and Technical Information of China (English)

    Ying ZHAO; Hai WANG

    2012-01-01

    Cumulative evidence suggests that renal vascular endothelial injury play an important role in initiating and extending tubular epithelial injury and contribute to the development of ischemic acute renal failure.Our previous studies have demonstrated that iptakalim's endothelium protection is related to activation of SUR2B/Kir6.1 subtype of ATP sensitive potassium channel (KATP) in the endothelium.It has been reported that SUR2B/Kir6.1 channels are widely distributed in the tubular epithelium,glomerular mesangium,and the endothelium and the smooth muscle of blood vessels.Herein,we hypothesized that activating renal KATP channels with iptakalim might have directly neroprotective effects.In this study,glomerular endothelial,mesangial and tubular epithelial cells which are the main cell types to form nephron were exposed to oleic acid (OA) at various concentrations for 24 h.0.25 μl/ml OA could cause cellular damage of glomerular endothelium and mesangium,while 1.25μl/ml OA could lead to the injury of three types of renal cells.It was observed that pretreatment with iptakalim at concentrations of 0.1,1,10 or 100 μmol/L prevented cellular damage of glomerular endothelium and tubular epithelium,whereas iptakalim from 1 to 100 μmol/L prevented the injury of mesangial cells.Our data showed iptakalim significantly increased survived cell rates in a concentration-dependent manner,significantly antagonized by glibenclamide,a KATP blocker.Iptakalim played a protective role in the main cell types of kidney,which was consistent with natakalim,a highly selective SUR2B/Kir6.1 channel opener.Iptakalim exerted protective effects through activating SUR2B/Kir6.1 channels,suggesting a new strategy for renal injury by its endothelial and renal cell protection.

  20. A high oleic sunflower oil fatty acid esters of plant sterols mixed with dietary diacylglycerol reduces plasma insulin and body fat accumulation in Psammomys obesus

    Directory of Open Access Journals (Sweden)

    Pelled Dori

    2009-10-01

    Full Text Available Abstract Background Metabolic syndrome is associated with subsequent development of cardiovascular diseases and type 2 diabetes. It is characterized by reduced response to insulin, central obesity, and dyslipidemia. Intake of plant sterols (PS has been shown to confer a healthier lipid profile and ameliorate cardiovascular disease risk factors in experimental animals and humans. In this study we used an animal model of type 2 diabetes to assess the effects of a preparation of PS esterified to high oleic sunflower oil fatty acids mixed with dietary diacylglycerol (PS-HOSO on diabetic related metabolic parameters. Psammomys obesus (P. obesus were fed high energy (HE diet supplemented by either PS-HOSO or control oil. Following 4.5 weeks of intervention, animals were divided into fasting and non-fasting modes prior to outcome measurements. Glucose and insulin levels as well as blood lipid profile, body weight, and fat accumulation were evaluated in fasting and non-fasting modes. Results P. obesus fed with a HE diet displayed a characteristic heterogeneity in their blood glucose and insulin levels with a subset group displaying type 2 diabetes symptoms. PS-HOSO treatment significantly reduced total cholesterol (24%, P P P P Conclusion PS-HOSO supplementation to diabetes-prone gerbils counteracts the increase in body weight and epididymal fat accumulation, and also results in a drop in circulating insulin levels. These effects are pointing out that PS-HOSO may serve as a functional ingredient for metabolic syndrome or diabetic sufferers, which not only influences body weight, but also prevents or reverses insulin resistance and hyperlipidemia.

  1. Dephosphorization of Steelmaking Slag by Leaching with Acidic Aqueous Solution

    Science.gov (United States)

    Qiao, Yong; Diao, Jiang; Liu, Xuan; Li, Xiaosa; Zhang, Tao; Xie, Bing

    2016-09-01

    In the present paper, dephosphorization of steelmaking slag by leaching with acidic aqueous solution composed of citric acid, sodium hydroxide, hydrochloric acid and ion-exchanged water was investigated. The buffer solution of C6H8O7-NaOH-HCl system prevented changes in the pH values. Kinetic parameters including leaching temperature, slag particle size and pH values of the solution were optimized. The results showed that temperature has no obvious effect on the dissolution ratio of phosphorus. However, it has a significant effect on the dissolution ratio of iron. The dephosphorization rate increases with the decrease of slag particle size and the pH value of the solution. Over 90% of the phosphorus can be dissolved in the solution while the corresponding leaching ratio of iron was only 30% below the optimal condition. Leaching kinetics of dephosphorization follow the unreacted shrinking core model with a rate controlled step by the solid diffusion layer, the corresponding apparent activation energy being 1.233 kJ mol-1. A semiempirical kinetic equation was established. After leaching, most of the nC2S-C3P solid solution in the steelmaking slag was selectively dissolved in the aqueous solution and the iron content in the solid residue was correspondingly enriched.

  2. Protective effect of low potassium dextran solution on acute kidney injury following acute lung injury induced by oleic acid in piglets

    Institute of Scientific and Technical Information of China (English)

    WU Rui-ping; LIANG Xiu-bin; GUO Hui; ZHOU Xiao-shuang; ZHAO Li; WANG Chen; LI Rong-shan

    2012-01-01

    Background Low potassium dextran (LPD) solution can attenuate acute lung injury (ALI).However,LPD solution for treating acute kidney injury secondary to ALI has not been reported.The present study was performed to examine the renoprotective effect of LPD solution in ALI induced by oleic acid (OA) in piglets.Methods Twelve animals that suffered an ALI induced by administration of OA into the right atrium were divided into two groups:the placebo group (n=6) pretreated with normal saline and the LPD group (n=6),pretreated with LPD solution.LPD solution was injected intravenously at a dose of 12.5 ml/kg via the auricular vein 1 hour before OA injection.Results All animals survived the experiments with mild histopathological injury to the kidney.There were no significant differences in mean arterial pressure (MAP),creatinin and renal damage scores between the two groups.Compared with the placebo group,the LPD group had better gas exchange parameters at most of the observation points ((347.0±12.6)mmHg vs.(284.3±11.3) mmHg at 6 hours after ALI,P<0.01).After 6 hours of treatment with OA,the plasma concentrations of NGAL and interleukin (IL)-6 in both groups increased dramatically compared to baseline ((6.0±0.6) and (2.50±0.08) folds in placebo group; and (2.5±0.5) and (1.40±0.05) folds in LPD group),but the change of both parameters in the LPD group was significantly lower (P <0.01) than in the placebo group.And 6 hours after ALl the kidney tissue concentration of IL-6 in the LPD group ((165.7 ± 22.5) pg.ml-1.g-1 protein) was significantly lower (P <0.01) than that in placebo group ((67.2± 25.3) pg.ml-1.g-1 protein).Conclusion These findings suggest that pretreatment with LPD solution via systemic administration might attenuate acute kidney injury and the cytokine response of IL-6 in the ALl piglet model induced by OA injection.

  3. Fermentation of aqueous plant seed extracts by lactic acid bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Schafner, D.W.; Beuchat, R.L.

    1986-05-01

    The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72 h period at 37 degrees C. Maximum bacterial populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products. 24 references.

  4. 单次鼻滴入油酸对SD大鼠的呼吸系统急性损伤作用%Acute Respiratory Injury on Rats after A Single Intranasal Administration of Oleic Acid

    Institute of Scientific and Technical Information of China (English)

    胡天羽; 李华; 马璟

    2013-01-01

    Seventy SD rats were randomly divided into the following 5 groups: blank control, bleomycin (5 mg/kg) and oleic acid (12, 60 and 120 mg/kg) groups. All test animals were administered intranasally at a single dose. Their respiratory rate (RR), tidal volume (TV) and minute volume (MV) were recorded by computer at 0.5, 1, 2, 4 and 8 h after administration. The animals were sacrificed in three batches on d3, d7, d21. The respiratory toxicity effect of oleic acid was evaluated according to total and classified inflammatory cell count, protein concentration and lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF) of the left lobe of lung. The hydroxyproline (HYP) content in right upper lobe of lung was determined and the histopathologic changes of right lower lobe were observed. The results showed that the RR level at 0.5 h of three oleic acid groups were obviously higher than that of blank control group, while the TV level were lower. Compared with the blank control group, the total number of inflammatory cells, neutrophilic granulocyte, eosinophilic granulocytes, protein concentration and LDH activity in BALF in high dose group of oleic acid were significantly increased and lung section showed inflammatory response and numerous foam cells. There were no significant differences between three oleic acid groups and blank control group in HYP content. It indicated that high dose of oleic acid had an acute injury on rat lung tissue and affected the respiratory function, but this effect was normally reversible.%将SD大鼠70只随机分为阴性对照组、博来霉素(5 mg/kg)对照组和油酸3个剂量(12、60和120 mg/kg)组,均采用单剂量鼻滴入给药.测定给药后0.5、1、2、4和8h时动物的呼吸频率、潮气量和每分通气量.给药后d3、d7和d21分批处死动物.取左肺叶进行支气管肺泡灌洗,进行灌洗液(BALF)中炎症细胞总数和分类计数,并测定全蛋白浓度和乳酸脱氢酶(LDH)活性;另取

  5. High-resolution neutron and X-ray diffraction room-temperature studies of an H-FABP–oleic acid complex: study of the internal water cluster and ligand binding by a transferred multipolar electron-density distribution

    Directory of Open Access Journals (Sweden)

    E. I. Howard

    2016-03-01

    Full Text Available Crystal diffraction data of heart fatty acid binding protein (H-FABP in complex with oleic acid were measured at room temperature with high-resolution X-ray and neutron protein crystallography (0.98 and 1.90 Å resolution, respectively. These data provided very detailed information about the cluster of water molecules and the bound oleic acid in the H-FABP large internal cavity. The jointly refined X-ray/neutron structure of H-FABP was complemented by a transferred multipolar electron-density distribution using the parameters of the ELMAMII library. The resulting electron density allowed a precise determination of the electrostatic potential in the fatty acid (FA binding pocket. Bader's quantum theory of atoms in molecules was then used to study interactions involving the internal water molecules, the FA and the protein. This approach showed H...H contacts of the FA with highly conserved hydrophobic residues known to play a role in the stabilization of long-chain FAs in the binding cavity. The determination of water hydrogen (deuterium positions allowed the analysis of the orientation and electrostatic properties of the water molecules in the very ordered cluster. As a result, a significant alignment of the permanent dipoles of the water molecules with the protein electrostatic field was observed. This can be related to the dielectric properties of hydration layers around proteins, where the shielding of electrostatic interactions depends directly on the rotational degrees of freedom of the water molecules in the interface.

  6. 一种新颖的油酸诱导乳猪急性肺损伤动物模型%A stable and reproducible piglet model of acute lung injury induced by injecting low-dose oleic acid

    Institute of Scientific and Technical Information of China (English)

    朱耀斌; 刘迎龙; 李晓锋; 王强; 张燕搏; 范祥明; 李志强; 许耀强; 凌峰; 刘爱军

    2011-01-01

    Objective To develop a hemodynamically stable and reproducible piglet model of acute lung injury by injecting low-dose oleic acid. Methods Six Chinese mini-piglets were injected with oleic acid-alcohol mixture (0. 1 mL/kg) via right atrial appendage cannula. The dose of each injection was 0. 1 mL and the interval was 90 seconds. Arterial oxygen pressure and the fraction of inspired oxygen were dynamically monitored. Circulation and respiratory function data were monitored. Right lower lung was histopathologically detected. Results There were significant differences in heart rate, mean arterial pressure, mean pulmonary arterial pressure, cardiac output, arterial oxygen pressure, arterial partial pressure of carbon dioxide, pH value, and arterial blood gas and oxygenation index between pre- and post-injection of oleic acid(Poleic acid.%目的 采用间断小剂量油酸注射方法,构建符合肺损伤标准、血流动力学稳定的乳猪急性肺损伤动物模型.方法 中华小型猪6只,经右心耳插管注射油酸-乙醇溶液0.1 mL/kg,0.1 mL/次,间隔90 s直至注射完毕.注射过程中监测循环、呼吸参数;实验结束取右下肺组织标本行组织病理检查.结果 油酸注射前、后心率、平均动脉压、平均肺动脉压、心输出量、动脉血氧分压、动脉血二氧化碳分压、pH值、氧合指数差异均有统计学意义(P<0.05).组织病理显示双肺呈弥漫性改变.结论 小剂量间断注射油酸可构建血流动力学稳定并符合肺损伤诊断标准的急性肺损伤动物模型.

  7. The reducibility of sulphuric acid and sulphate in aqueous solution

    International Nuclear Information System (INIS)

    In connection with the Swedish project for final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister. A simple reaction between copper and sulphate is thermodynamically impossible, but copper can react to give copper sulphide if an additional electron donor such as iron(II) is available. The problem was extended to the more general question of the reducibility of sulphur(VI) in dilute aqueous solution. Chemical reduction of sulphate does not take place in dilute solution at temperatures below 100oC. In experiments on the reduction of sulphates under hydrothermal conditions a reaction only takes place at temperatures above 275-300oC. The oxidising action of sulphuric acid on metals becomes perceptible only at acid concentrations over 45-50%. In experiments on the cathodic reduction of 74% sulphuric acid the formation of hydrogen sulphide and elementary sulphur starts, depending on the current density, at 50-130oC, and polarographic measurements suggest that the reducible species is not the hydrogen sulphate ion but molecular sulphuric acid. The resistance of copper to oxygen-free sulphuric acid up to a concentration of 60% is well-known. Numerous processes in industrial electrochemistry take place in sulphuric acid or sulphate electrolytes. The reversible metal/metal-sulphate electrodes of lead and cadmium are unstable relative to the corresponding metal sulphides. Nevertheless the reversible lead sulphate electrode does not fail from sulphide formation. All these facts confirm that sulphur(VI) in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be almost certainly be ruled out. (author) 5 figs., 85 refs

  8. Electrostatic interactions play an essential role in the binding of oleic acid with α-lactalbumin in the HAMLET-like complex: a study using charge-specific chemical modifications.

    Science.gov (United States)

    Xie, Yongjing; Min, Soyoung; Harte, Níal P; Kirk, Hannah; O'Brien, John E; Voorheis, H Paul; Svanborg, Catharina; Hun Mok, K

    2013-01-01

    Human α-lactalbumin made lethal to tumor cells (HAMLET) and its analogs are partially unfolded protein-oleic acid (OA) complexes that exhibit selective tumoricidal activity normally absent in the native protein itself. To understand the nature of the interaction between protein and OA moieties, charge-specific chemical modifications of lysine side chains involving citraconylation, acetylation, and guanidination were employed and the biophysical and biological properties were probed. Upon converting the original positively-charged lysine residues to negatively-charged citraconyl or neutral acetyl groups, the binding of OA to protein was eliminated, as were any cytotoxic activities towards osteosarcoma cells. Retention of the positive charges by converting lysine residues to homoarginine groups (guanidination); however, yielded unchanged binding of OA to protein and identical tumoricidal activity to that displayed by the wild-type α-lactalbumin-oleic acid complex. With the addition of OA, the wild-type and guanidinated α-lactalbumin proteins underwent substantial conformational changes, such as partial unfolding, loss of tertiary structure, but retention of secondary structure. In contrast, no significant conformational changes were observed in the citraconylated and acetylated α-lactalbumins, most likely because of the absence of OA binding. These results suggest that electrostatic interactions between the positively-charged basic groups on α-lactalbumin and the negatively-charged carboxylate groups on OA molecules play an essential role in the binding of OA to α-lactalbumin and that these interactions appear to be as important as hydrophobic interactions.

  9. Adsorption of itaconic acid from aqueous solutions onto alumina

    Directory of Open Access Journals (Sweden)

    JELENA J. GULICOVSKI

    2008-08-01

    Full Text Available Itaconic acid, IA (C5H6O4, was investigated as a potential flocculant for the aqueous processing of alumina powders. The adsorption of IA, as a function of its concentration and pH value of the solution, onto the alumina surface was studied by the solution depletion method. The stability of the suspensions in the presence of itaconic acid was evaluated in light of the surface charge of the alumina powder used, the degree of dissociation of IA, as well as the sedimentation behavior and rheology of the suspensions. It was found that the adsorption process is extremely pH dependent; the maximum adsorption of IA onto alumina surface occurring at a pH close to the value of the first IA dissociation constant, pKa1. Also, IA does not influence the value of the point of zero charge of alumina. It was shown that IA represents an efficient flocculant for concentrated acidic alumina suspensions.

  10. Surface oxide growth on platinum electrode in aqueous trifluoromethanesulfonic acid

    Science.gov (United States)

    Furuya, Yoshihisa; Mashio, Tetsuya; Ohma, Atsushi; Dale, Nilesh; Oshihara, Kenzo; Jerkiewicz, Gregory

    2014-10-01

    Platinum in the form of nanoparticles is the key and most expensive component of polymer electrolyte membrane fuel cells, while trifluoromethanesulfonic acid (CF3SO3H) is the smallest fluorinated sulfonic acid. Nafion, which acts as both electrolyte and separator in fuel cells, contains -CF2SO3H groups. Consequently, research on the electrochemical behaviour of Pt in aqueous CF3SO3H solutions creates important background knowledge that can benefit fuel cell development. In this contribution, Pt electro-oxidation is studied in 0.1 M aqueous CF3SO3H as a function of the polarization potential (Ep, 1.10 ≤ Ep ≤ 1.50 V), polarization time (tp, 100 ≤ tp ≤ 104 s), and temperature (T, 278 ≤ T ≤ 333 K). The critical thicknesses (X1), which determines the applicability of oxide growth theories, is determined and related to the oxide thickness (dox). Because X1 > dox for the entire range of Ep, tp, and T values, the formation of Pt surface oxide follows the interfacial place-exchange or the metal cation escape mechanism. The mechanism of Pt electro-oxidation is revised and expanded by taking into account possible interactions of cations, anions, and water molecules with Pt. A modified kinetic equation for the interfacial place exchange is proposed. The application of the interfacial place-exchange and metal cation escape mechanisms leads to an estimation of the Ptδ+-Oδ- surface dipole (μPtO), and the potential drop (Vox) and electric field (Eox) within the oxide. The Pt-anion interactions affect the oxidation kinetics by indirectly influencing the electric field within the double layer and the surface oxide.

  11. Friction Reduction and Antiwear Properties of Serpentine and Oleic Acid as Lubricating Oil Additives%蛇纹石和油酸作为润滑油添加剂的减摩抗磨性能∗

    Institute of Scientific and Technical Information of China (English)

    司友波; 常秋英; 乔姣飞; 崔艳斌

    2015-01-01

    利用高能球磨机制备平均粒径约1μm的蛇纹石超细粉体,并将其与油酸按质量比2∶1混合分散到PAO10基础油中,利用四球试验机探究其作为润滑油添加剂的减摩抗磨性能,利用白光干涉仪分析磨斑表面三维形貌,并用EDAX对磨斑表面元素进行分析。结果表明:蛇纹石与油酸混合加入基础油中具有更好的减摩抗磨效果;蛇纹石粉体与油酸混合后能够在摩擦副表面形成含有Si、 Mg元素的修复膜,而单一的蛇纹石粉体在摩擦过程中不能成膜,这是因为,油酸作为分散剂能够吸附摩擦过程中产生的金属磨粒并使其分散到润滑油里,减少磨粒对摩擦表面造成的磨粒磨损;油酸有机修饰层吸附到蛇纹石颗粒表面,改善了蛇纹石颗粒在基础油中的分散性。%Ultrafine serpentine powder with average particle size of 1 μm was prepared with high⁃energy ball⁃milling method.Serpentine powder was added to the PAO10 base oil with oleic acid according to mass ratio of 2 ∶ 1.The friction and antiwear properties of the lubricant additives were investigated by four⁃ball machine, and the three dimensional mor⁃phology of worn surface was characterized by the White Light Interferometers, and the elements of worn surface were ana⁃lyzed with EDAX. Results indicate that compared to serpentine powder, the compound additives consisted of serpentine powder and oleic acid can reduce friction and wear more efficiently.A tribofilm is formed on the worn surface with the pres⁃ence of Si, Mg elements under the compound additives of serpentine powder and oleic acid, while the tribofilm cannot be formed on the worn surface lubricated under the single additive of serpentine powder.It is because that the oleic acid as a dispersant can absorb metal wear particles produced in the friction process, and disperse them into lubricant, so the abra⁃sive wear is reduced on worn surface.The organic tribofim

  12. Decomposition of perfluorocarboxylic acids (PFCAs) by heterogeneous photocatalysis in acidic aqueous medium.

    Science.gov (United States)

    Panchangam, Sri Chandana; Lin, Angela Yu-Chen; Shaik, Khaja Lateef; Lin, Cheng-Fang

    2009-09-01

    Decomposition of perfluorocarboxylic acids (PFCAs) is of prime importance since they are recognized as persistent organic pollutants and are widespread in the environment. PFCAs with longer carbon chain length are particularly of interest because of their noted recalcitrance, toxicity, and bioaccumulation. Here in this study, we demonstrate efficient decomposition of three important PFCAs such as perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) by heterogeneous photocatalysis with TiO(2) as a photocatalyst in acidic aqueous solutions. The PFCAs were decomposed into shorter carbon chain length PFCAs and fluoride ions. Photoholes of excited TiO(2) generated upon UV-irradiation are found to be the oxidation sites for PFCAs. Therefore, creation and sustenance of these photoholes in the acidic aqueous medium has enhanced the decomposition of PFCAs. Heterogeneous photocatalytic treatment achieved more than 99% decomposition and 38% complete mineralization of PFOA in 7h. The decomposition of other PFCAs was as high as 99% with a defluorination efficiency of 38% for PFDA and 54% for PFNA. The presence of perchloric acid was found to enhance the decomposition by facilitating the ionization of PFCAs. The oxygen present in the medium served both as an oxidant and an electron acceptor. The mechanistic details of PFCA decomposition and their corresponding mineralization are elaborated.

  13. Liquid to Semisolid Rheological Transition of Normal and High-Oleic Peanut Oils Upon Cooling to Refrigeration Temperatures

    Science.gov (United States)

    Rheological transitions of peanut oils cooled from 20 to 3ºC at 0.5ºC/min were monitored via small strain oscillatory measurements at 0.1 Hz and 1 Pa. Oils were from 9 different cultivars of peanut, and 3 oils were classified as high-oleic (approximately 80% oleic acid). High-oleic oils maintained...

  14. Humic acid removal from aqueous solutions by peroxielectrocoagulation process

    Directory of Open Access Journals (Sweden)

    Ahmad Reza Yazdanbakhsh

    2015-06-01

    Full Text Available Background: Natural organic matter is the cause of many problems associated with water treatment such as the presence of disinfection by-products (DBPs and membrane fouling during water filtration. In this study, the performance of the peroxi-electrocoagulation process (PEP was investigated for the removal of humic acids (HAs from aqueous solutions. Methods: PEP was carried out for the removal of HA using a plexiglas reactor with a volume of 2 L and fitted with iron electrodes and a direct current supply (DC. Samples were taken at various amounts of pH (2-4, current density (1 and 2A/cm2, hydrogen peroxide (50-150 mg/L and reaction time (5-20 minutes and then filtered to remove sludge formed during reaction. Finally, the HA concentration was measured by UV absorbance at 254 nm (UV254. Results: Results indicated that increasing the concentration of H2O2 from 50 to 150 mg/L increased HA removal efficiency from 83% to 94.5%. The highest removal efficiency was observed at pH 3.0; by increasing the pH to the alkaline range, the efficiency of the process was reduced. It was found that HA removal efficiency was high in current density 1A/cm2. Increasing current density up to 1 A cm-2 caused a decrease in removal efficiency. Results of this study showed that under the optimum operating range for the process ([current density] = 1A/cm2, [hydrogen peroxide concentration] = 150 mg/L, [reaction time]= 20 minutes and [pH]= 3.0, HA removal efficiency reached 98%. Conclusion: It can be concluded that PEP has the potential to be utilized for cost-effective removal of HA from aqueous solutions.

  15. Synthesis and physical properties of new coco-oleic estolide branched esters

    Science.gov (United States)

    Oils derived from vegetable oils tend to not meet the standards for industrial lubricants because of unacceptable low temperature properties, pour point (PP), and/or cloud point (CP). However, a catalytic amount of perchloric acid with oleic and coconut (coco) fatty acids produced a coco-oleic estol...

  16. INTERACTION OF AQUEOUS SOLUTIONS OF CHLORINE WITH MALIC ACID, TARTARIC ACID, AND VARIOUS FRUIT JUICES, A SOURCE OF MUTAGENS

    Science.gov (United States)

    The interactions of aqueous solutions of chlorine with some fruit acids (citric acid, DL-malic acid, and L-tartaric acid) at different pH values were studied. iethyl ether extraction followed by GC/MS analysis indicated that a number of mutagens (certain chlorinated propanones an...

  17. Role of oleic acid in immune system; mechanism of action: a review Papel del ácido oleico en el sistema inmune; mecanismo de acción: revisión científica

    Directory of Open Access Journals (Sweden)

    C. Carrillo

    2012-08-01

    Full Text Available Introduction: Although n-3 polyunsaturated fatty acids have been widely described as anti-inflammatory fats, little is known about the role of oleic acid in immune system. Aim: The aim of the present review is to join all the reports available in order to analyze where exactly the knowledge concerning this topic is and what the causes of the controversial data could be. Methods: We searched electronic databases and bibliographies of selected articles were inspected for further reference. Results: Diets rich in oleic acid have beneficial effects in inflammatory-related diseases. In addition, a wide range of studies evaluate the effect of oleic acid in different cellular functions thus reporting a potential mechanism for the biological effect of such a fat. However, some controversial data can be found in literature, maybe related to the kind of study or even the dose of the reagent added. Conclusion: In conclusion, oleic acid could be reported as an anti-inflammatory fatty acid playing a role in the activation of different pathways of immune competent cells.Introducción: Los ácidos grasos poliinsaturados de la familia n-3 han sido ampliamente caracterizados por su potencial antiinflamatorio. Sin embargo, las evidencias relativas al papel del ácido oleico en el sistema inmune son escasas. Objetivo: El objetivo de la presente revisión bibliográfica es hacer una recopilación de todos y cada uno de los trabajos publicados a este respecto, al objeto de evaluar dónde se encuentra el conocimiento relativo a esta área y cuáles pueden ser las causas de los resultados contradictorios. Métodos: Se ha realizado una búsqueda bibliográfica a través de bases de datos electrónicas y las referencias de los artículos de interés han sido utilizadas como fuente de búsquedas más avanzadas. Resultados: Las dietas ricas en ácido oleico parecen estar asociadas con un beneficio en determinadas patologías de base inflamatoria. Además, un gran n

  18. Synthetic technology of castor oleic acid Trimethylolpropane ester%蓖麻油酸三羟甲基丙烷酯的合成工艺条件及性能

    Institute of Scientific and Technical Information of China (English)

    焦体; 胡文云; 唐志辉; 周诗磊; 邹晨

    2012-01-01

    以蓖麻油和三羟甲基丙烷为原料,通过皂化,酯化合成蓖麻油酸三羟酯,研究了原料配比,催化剂用量,反应温度,反应时间等对酯化反应的影响,最佳条件为:蓖麻油与三羟甲基丙烷的摩尔比为5∶4,,催化剂用量为蓖麻油酸质量的0.5%,反应温度180 ~ 200℃,反应时间4h.生成的蓖麻油酸三羟甲基丙烷酯为黄色透明液体,产率为86.48%,用红外光谱进行了定性分析,证明了目标产物的存在,采用了热重/差热综合热分析仪研究了其热稳定性,采用了运动粘度测定仪研究了其粘温性能.结果表明:其润滑性能、热稳定性、粘温性能满足工艺润滑油基础油的要求.%With castor oil and Trimethylolpropane as raw material, castor oleic acid ester was synthesized by the saponification and esterification. The ratio of raw material, catalyst dosage, reaction temperature and reaction time on the esterification of influence was studied. And the best conditions were as follows; castor oil and Trimethylolpropane mole ratio of 5: 4, catalyst dosage of the mass of oleic acid castor for 0. 5 % , reaction temperature 180-200 °C , reaction time 4 h. The Castor oleic acid Trimethylolpropane ester is a kind of yellow transparent liquid, production rate is 86.48%. It is proved the existence of the target product with infrared spectra of qualitative analysis. The results show that; the lubrication properties, thermal stability, glue temperature performance meet the technological requirements of base oil lubricating oil.

  19. Optical properties of chitosan in aqueous solution of L- and D-ascorbic acids

    Science.gov (United States)

    Malinkina, Olga N.; Shipovskaya, Anna B.; Kazmicheva, Olga F.

    2016-04-01

    The optical properties of aqueous chitosan solutions in L- and D-ascorbic acids were studied by optical rotatory dispersion and spectrophotometry. The specific optical rotation [α] of all chitosan solutions tested was positive, in contrast to aqueous solutions of the ascorbic acid enantiomers, which exhibit an inverse relationship of [α] values. Significant differences in the absolute values of [α] of the chitosan solutions at polymer-acid ratios exceeding the equimolar one were found.

  20. 利用真空FTIR比较研究油酸薄膜和油酸包覆粉煤灰分别与臭氧的非均相化学反应动力学%A Comparison of Heterogeneous Reaction Kinetics of Oleic Acid Thin Film and Oleic Acid Coated Flyash with Ozone Using Vacuum FTIR

    Institute of Scientific and Technical Information of China (English)

    何翔; 冷春波; 张韫宏

    2016-01-01

    气溶胶老化是目前大气颗粒物物理化学领域的研究热点之一。通过真空型傅里叶红外光谱仪原位观测并对比了油酸(OA)薄膜和油酸包覆粉煤灰两种样品分别与臭氧发生的化学反应动力学,并评估了其中粉煤灰在非均相化学反应中所起到的作用。除了指纹区特征峰的不同,在反应前纯油酸薄膜和纯油酸包覆粉煤灰样品的主要红外特征吸收峰是相似的。当两种样品分别处于20 ppm 臭氧浓度、室温和干燥的反应环境中,—CH 的特征吸收峰(3050 cm-1)强度降低而—OH 伸缩振动特征峰(3430 cm-1)强度增加。此外,随着臭氧氧化反应的进行,处于1710cm-1的羧酸 C—O 伸缩振动特征峰强度下降,反之,产物酯类物质的伸缩振动特征峰在1740 cm-1出现并增强。通过红外光谱的变化趋势能够得到两组样品的 OA 成分在反应中逐步消耗并转化为含有羟基和酯类官能团的产物。通过位于1740 cm-1处的 C—O 特征峰的变化能够得到准一级反应速率常数Kapp和摄取系数γ。粉煤灰样品的准一级反应速率常数大体是油酸薄膜反应体系的两倍。对于比表面积,粉煤灰样品要大于油酸薄膜,而两种反应体系的臭氧浓度一致,油酸薄膜和油酸包覆粉煤灰的γ值分别为(2.70±0.11)×10-4和(3.70±0.13)×10-4。较大的催化表面积和较快的催化效率是导致粉煤灰样品较油酸薄膜反应快的原因。由此证明了当粉煤灰与不饱和有机酸结合并处在臭氧氧化环境中时会常易促进二次有机气溶胶的形成。%Aerosol aging is the one of the research hotspots in the field of physical chemistry of atmospheric particulates at present.This study evaluates the impact of flyash in heterogenous reaction through the compari-sion of ozone oxidation reaction kinetics between the oleic acid (OA)thin film and oleic acid coated flyash which are observed by in situ vacuum FTIR

  1. Kinetics of adsorption of oleic acid from soybean oil by alkaline clay%碱性白土吸附大豆油中油酸的动力学研究

    Institute of Scientific and Technical Information of China (English)

    霍英霞; 童张法; 韦藤幼

    2014-01-01

    The kinetics of adsorption of oleic acid from soybean oil by alkaline clay under the conditions of different water contents of alkaline clay,different adsorption temperatures and different initial contents of oleic acid of soybean oil was studied. The results showed that the adsorption process was in line with the quasi-second order kinetic equation with correlation coefficient R2 above 0. 995 and the theoretical equi-librium adsorption capacity was close to the experimental value;the adsorption rate increased obviously with the water content of alkaline clay increasing;the adsorption rate constant hardly changed with the content of oleic acid of soybean oil increasing,which manifested chemical adsorption control;the adsorp-tion rate constant increased while the balance adsorption capacity decreased with the adsorption tempera-ture rising,which indicated that the adsorption was an exothermic process and manifested physical adsorp-tion control. The activation energy of the adsorption was 70. 7 kJ/mol,which was between physical ad-sorption and chemical adsorption. Therefore,the adsorption of oleic acid from soybean oil by alkaline clay was controlled by both chemical adsorption and physical adsorption.%研究不同碱性白土的含水量、吸附温度及大豆油中初始油酸含量条件下,碱性白土吸附大豆油中油酸的动力学。结果表明:吸附过程符合拟二级动力学方程,相关系数R2>0.995,由模型拟合得出的平衡吸附量与实验值接近;碱性白土含水量增加,吸附速率明显加快;吸附速率常数不随大豆油中油酸含量升高而变化,表现为化学吸附控制;而吸附速率常数随着吸附温度的升高而增大,平衡吸附量则随吸附温度升高而减少,说明此吸附为放热过程,表现为物理吸附控制。吸附活化能为70.7 kJ/mol,该活化能介于物理吸附和化学吸附之间,故碱性白土对大豆油中油酸的吸附是化学吸附和物理吸附共同控制的。

  2. Activation of Carbonyl-Containing Molecules with Solid Lewis Acids in Aqueous Media

    Energy Technology Data Exchange (ETDEWEB)

    Román-Leshkov, Yuriy [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Chemical Engineering; Davis, Mark E. [California Inst. of Technology (CalTech), Pasadena, CA (United States). Chemical Engineering

    2011-09-28

    Current interest in reacting carbonyl-containing molecules in aqueous media is primarily due to the growing emphasis on conversion of biomass to fuels and chemicals. Recently, solid Lewis acids have been shown to perform catalytic reactions with carbonyl-containing molecules such as sugars in aqueous media. Here, catalysis mediated by Lewis acids is briefly discussed, Lewis acid solids that perform catalysis in aqueous media are then described, and the review is concluded with a few comments on the outlook for the future.

  3. Transformations of polyols to organic acids and hydrogen in aqueous alkaline media

    NARCIS (Netherlands)

    Haasterecht, van T.; Deelen, van T.W.; Jong, de K.P.; Bitter, J.H.

    2014-01-01

    In this paper we show that carbon nanofiber supported copper and nickel nanoparticles can selectively transform ethylene glycol and glycerol into value added oxygenates (organic acids) under anaerobic aqueous conditions. During aqueous phase oxidation Cu based catalysts showed a nearly quantitative

  4. Amelioration by chicory seed extract of diabetes- and oleic acid-induced non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) via modulation of PPARα and SREBP-1.

    Science.gov (United States)

    Ziamajidi, Nasrin; Khaghani, Shahnaz; Hassanzadeh, Gholamreza; Vardasbi, Safura; Ahmadian, Shahram; Nowrouzi, Azin; Ghaffari, Seyed Mahmood; Abdirad, Afshin

    2013-08-01

    We evaluated the effect of chicory (Cichorium intybus L.) seed extract (CI) on hepatic steatosis caused by early and late stage diabetes in rats (in vivo), and induced in HepG2 cells (in vitro) by BSA-oleic acid complex (OA). Different dosages of CI (1.25, 2.5 and 5 mg/ml) were applied along with OA (1 mM) to HepG2 cells, simultaneously and non-simultaneously; and without OA to ordinary non-steatotic cells. Cellular lipid accumulation and glycerol release, and hepatic triglyceride (TG) content were measured. The expression levels of sterol regulatory element-binding protein-1c (SREBP-1c) and peroxisome proliferator-activated receptor alpha (PPARα) were determined. Liver samples were stained with hematoxylin and eosin (H&E). Significant histological damage (steatosis-inflammation-fibrosis) to the cells and tissues and down-regulation of SREBP-1c and PPARα genes that followed steatosis induction were prevented by CI in simultaneous treatment. In non-simultaneous treatment, CI up-regulated the expression of both genes and restored the normal levels of the corresponding proteins; with a greater stimulating effect on PPARα, CI acted as a PPARα agonist. CI released glycerol from HepG2 cells, and targeted the first and the second hit phases of hepatic steatosis. A preliminary attempt to characterize CI showed caffeic acid, chlorogenic acid, and chicoric acid, among the constituents. PMID:23603006

  5. Oxidative aromatization of Hantzsch 1,4-dihydropyridines by aqueous hydrogen peroxide-acetic acid

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A simple method for the oxidative aromatization of Hantzsch 1,4-dihydropyridines to the corresponding pyridines is achieved by using hydrogen peroxide as green oxidant and acetic acid as catalyst in aqueous solution.

  6. Thermodynamics of the complexation of arabinogalactan with salicylic and p-aminobenzoic acids in aqueous solutions

    Science.gov (United States)

    Mudarisova, R. Kh.; Badykova, L. A.

    2016-03-01

    The thermodynamics of complexation of arabinogalactan with salicylic and p-aminobenzoic acids in aqueous solutions is studied by means spectroscopy. The standard thermodynamic characteristics (Δ H°; Δ G°; Δ S°) of complexation are calculated.

  7. Development of high oleic soybean mutant and its stability across the environments

    International Nuclear Information System (INIS)

    Modifying seed oil composition has become a major goal in soybean breeding programs. Elevated oleic acid and reduced linoleic and linolenic acid content can improve the oxidative stability, flavor and nutritional value of soybean oil. It is also important to study the effect of the environment on the altered fatty acid content in soybean to determine their stability over different growing conditions. The objectives of this study were to develop a high oleic acid soybean mutant and to determine the stability of fatty acid composition of the same across different environments. A high oleic acid mutant (HOM) containing 40% of oleic acid compared to 27% in parent cultivar 'MACS 450' was selected from a mutagen treatment of 200Gy and 0.15% Ethyl Methane Sulphonate (EMS). To study the influence of the environmental factors on fatty acid composition, the HOM along with other four soybean lines MACS 1034, MACS 1055, MACS 1092 and Bragg were grown at 12 locations. Seeds of each genotype from each location were analyzed for fatty acid composition by gas chromatography. Eberhart and Russell's model was used to study the stability of fatty acids. In general, all the fatty acids were influenced by the environmental factors. Elevated oleic acid in HOM was less stable across the environments compared to oleic acid in other four cultivars. The mean oleic acid content in 'HOM' was 31.26-45.18% over the 12 locations. Linoleic acid content in 'HOM' and 'MACS 1034' was also showed significant deviation from unity for regression coefficient showing its unstable nature. This study shows that the elevated oleic and reduced linoleic acids in 'HOM' are highly influenced by the environmental factors. (author)

  8. Development of a High Oleic Soybean Mutant and its Stability Across the Environments

    International Nuclear Information System (INIS)

    Modifying seed oil composition has become a major goal in soybean breeding programmes. Elevated oleic acid and reduced linoleic and linolenic acid content can improve the oxidative stability, flavor and nutritional value of soybean oil. The objectives of this study were (1) to develop a high oleic acid soybean mutant and (2) to determine the stability of its fatty acid composition across different environments. A high oleic acid mutant (HOM), containing 40% of oleic acid compared to 27% in parent cultivar MACS 450, was selected from a treatment with 200Gy γ-rays and 0.15% ethyl methane sulphonate (EMS). To investigate the influence of environmental factors on fatty acid composition, the HOM, along with four other soybean lines (MACS 1034, MACS 1055, MACS 1092 and Bragg) was grown at 12 locations. Seeds of each genotype from each location were analyzed for fatty acid composition by gas chromatography. Eberhart and Russell's linear regression model was used to study the environmental stability of fatty acid composition. In general, all the fatty acids studied were influenced by environmental factors. Elevated oleic acid in the HOM was less stable across environments than the oleic acid content in the other four cultivars. The mean oleic acid content in the HOM was 31.26 - 45.18% over the 12 locations. Linoleic acid content in the HOM and in MACS 1034 also showed significant deviation from unity for their regression coefficient, indicating significant environmental effects. This study shows that extent of the elevation of oleic acid and reduction of linoleic acid content in the HOM are strongly influenced by environmental factors. (author)

  9. Succinic acid in aqueous solution : connecting microscopic surface composition and macroscopic surface tension

    OpenAIRE

    Werner, Josephina; Julin, Jan; Dalirian, Maryam; Prisle, Nønne; Öhrwall, Gunnar; Persson, Ingmar; Björneholm, Olle; Riipinen, Ilona

    2014-01-01

    The water vapor interface of aqueous solutions of succinic acid, where pH values and bulk concentrations were varied, has been studied using surface sensitive X-ray photoelectron spectroscopy (XPS) and molecular dynamics (MD) simulations. It was found that succinic acid has a considerably higher propensity to reside in the aqueous surface region than its deprotonated form, which is effectively depleted from the surface due to the two strongly hydrated carboxylate groups. From both XPS experim...

  10. Radiation-induced destruction peculiarities of hydroxyl containing amino acids in diluted aqueous solution

    International Nuclear Information System (INIS)

    Amino acids aqueous solution of alpha-alanine and beta-alanine, serine, threonine (concentration 5*10-4 M) were irradiated with dose rate 0.35 Gy/s in range 100-1100 Gy and analysed. Effectiveness of radiation-induced decomposition process depends on row of factors: concentration of amino acid aqueous solution, pH, oxygen presence and other acceptors

  11. 法国海岸松树皮提取物碧萝芷对长链游离脂肪酸诱导的巨噬细胞perilipin2基因表达的影响%Pycnogenol, an Extract from French Martime Pine, Suppresses Oleic Acid-induced perilipin2 Expression in Macrophages

    Institute of Scientific and Technical Information of China (English)

    范斌; 杜强; 谷剑秋; 张锦

    2011-01-01

    Abstract Objective To investigate the effect of Pycnogenol on oleic acid-induced perilipin2 expression in macrophages. Methods Realtime PCR and Western blot were performed to detect perilipin2 expression. Transient transfection and luciferase assay were employed to measure perilipin2 promoter activity. Results Oleic acid significantly induced perilipiti2 expression in a dose-and time-dependent manner in macrophages; oleic acid markedly enhanced perilipin2 promoter activity; Pycnogenol significantly suppressed oleic acid-induced perihpin2 expression and promoter activity. Conclusion For the first time,we demonstrated that Pycnogenol significantly suppressed oleic acid-induced perilipin2 expression and promoter activity.%目的 研究碧萝芷(PYC)对油酸诱导的巨噬细胞perilipin2表达的影响及其相关分子机制.方法 应用Real-time PCR 和Western blot测定油酸及PYC对perilipin2 mRNA和蛋白水平表达影响.应用荧光素酶活性分析方法检测油酸及PYC时perilipin2启动子活性的影响.结果油酸以剂量和浓度依赖方式上调perilipin2 mRNA和蛋白水平表达,并促进perilipin2启动子活性.PYC以剂量依赖方式抑制了油酸诱导的perilipin2表达及启动子活性.结论PYC抑制了巨噬细胞中油酸诱导的perilipin2的表达.PYC通过抑制perilipin2启动子活性,从而直接抑制perilipin2的表达.

  12. Surfactant-Amino Acid and Surfactant-Surfactant Interactions in Aqueous Medium: a Review.

    Science.gov (United States)

    Malik, Nisar Ahmad

    2015-08-01

    An overview of surfactant-amino acid interactions mainly in aqueous medium has been discussed. Main emphasis has been on the solution thermodynamics and solute-solvent interactions. Almost all available data on the topic has been presented in a lucid and simple way. Conventional surfactants have been discussed as amphiphiles forming micelles and amino acids as additives and their effect on the various physicochemical properties of these conventional surfactants. Surfactant-surfactant interactions in aqueous medium, various mixed surfactant models, are also highlighted to assess their interactions in aqueous medium. Finally, their applied part has been taken into consideration to interpret their possible uses.

  13. pH对油酸水解废水酸化发酵过程的影响%Effect of pH on the Acidification Fermentation Process in Oleic Acid Hydrolysis Wastewater

    Institute of Scientific and Technical Information of China (English)

    吴九九; 刘建平; 杨春燕

    2012-01-01

    pH对油酸水解废水酸化发酵影响的研究表明,pH不仅对酸化速率有很大影响,而且也会影响酸化产物的构成;不同pH值下酸化的主要产物是乙酸,但酸化的最佳pH值为6.5,此pH条件下VFA的产量最高可达12.53 g/L;在pH〉7时,明显有丙酸生成。%The impact of pH on the environment of acidification fermentation in oleic acid hydrolysis wastewater is studied, and the results show that pH has a great influence not only on the rate of acidi- fication ,but also on the composition of acidification products. The chief product of acidification is acetic acid under different pH value. The most favorable pH value in acidification is 6.5, at which the highest yielding of VFA ( 12.53 g/L) was obtained. The formation of propionic acid is apparent when pH 〉 7.

  14. 利用甘蓝型油菜高密度SNP遗传图谱定位油酸、亚麻酸及芥酸含量QTL位点%QTL Mapping of Oleic Acid, Linolenic Acid and Erucic Acid Content in Brassica napus by Using the High Density SNP Genetic Map

    Institute of Scientific and Technical Information of China (English)

    刘列钊; 李加纳

    2014-01-01

    [Objective]Rapesee d oil contains many fatty acid components and the major goal in breeding and genetic research is to increase of the oleic acid content and decreases of the linolenic acid and erucic acid content. QTL mapping of oil quality related oleic acid, linolenic acid and erucic acid content in Brassica napus was made by using the high density SNP genetic map which was constructed from the high generation RIL population with the newly developed rapeseed 60K chip array. [Method] The high generation RIL population was derived from the cross of high erucic acid female parent GH06 and low erucic acid male parent P174. Seeds harvested from Giessen and Hohenlieth in Germany in 2008 and again in Giessen in 2009 were measured by NIRS with three technical repeats. The RIL population genotype was analyzed with the newly developed rapeseed 60K chip array. The DNA preparation and the chip preparation were processed strictly according to Infinium HD Assay Ultra manual of Illumina Inc. The SNP linkage map was constructed by using MSTmap program with minimum LOD 5.0. The reference SNP genetic map contains 2756 SNP markers, covering 1 832.4 cM of B. napus genome. QTL mapping of oleic acid, linolenic acid and erucic acid content was conducted by composite interval mapping using software Windows QTL Cartographer. [Result] Trait analysis indicated that the oleic acid and erucic acid contents were controlled by major genes, and their correlation coefficient was higher than-0.95 in the three different environments at significant level. Linolenic content showed a negative and positive correlation with erucic acid and oleic acid content, respectively. Two major QTL located on A08 and C03 were detected both for oleic acid and erucic acid content at the same position. In the three different environments, the major oleic acid QTL accounted for the phenotype variation from 19%to 31%, and the major erucic acid QTL effects varied from 19%to 34%, and the two major QTL for oleic acid and

  15. Effects of conjugated linoleic acid and high oleic acid safflower oil in the treatment of children with HPV-induced laryngeal papillomatosis: a randomized, double-blinded and crossover preliminary study

    Directory of Open Access Journals (Sweden)

    Louw Louise

    2012-10-01

    Full Text Available Abstract Background Surgery is the mainstay therapy for HPV-induced laryngeal papillomatosis (LP and adjuvant therapies are palliative at best. Research revealed that conjugated-linoleic acid (CLA may improve the outcome of virally-induced diseases. The effects of Clarinol™ G-80 (CLA and high oleic safflower oil (HOSF on children with LP (concomitant with surgery were evaluated. Design A randomized, double-blinded, crossover and reference-oil controlled trial was conducted at a South African medical university. Study components included clinical, HPV type/load and lymphocyte/cytokine analyses, according to routine laboratory methods. Participants Overall: ten children enrolled; eight completed the trial; five remained randomized; seven received CLA first; all treatments remained double-blinded. Intervention Children (4 to 12 years received 2.5 ml p/d CLA (8 weeks and 2.5 ml p/d HOSF (8 weeks with a washout period (6 weeks in-between. The one-year trial included a post-treatment period (30 weeks and afterwards was a one-year follow-up period. Main outcome measures Changes in numbers of surgical procedures for improved disease outcome, total/anatomical scores (staging system for papillomatosis prevention/viral inhibition, and lymphocyte/cytokine counts for immune responses between baselines and each treatment/end of trial were measured. Findings After each treatment all the children were in remission (no surgical procedures; after the trial two had recurrence (surgical procedures in post-treatment period; after the follow-up period three had recurrence (several surgical procedures and five recovered (four had no surgical procedures. Effects of CLA (and HOSF to a lesser extent were restricted to mildly/moderately aggressive papillomatosis. Children with low total scores (seven/less and reduced infections (three/less laryngeal sub-sites recovered after the trial. No harmful effects were observed. The number of surgical procedures during the trial

  16. A pulse radiolysis study of salicylic acid and 5-sulpho-salicylic acid in aqueous solutions

    International Nuclear Information System (INIS)

    Reactions of H, OH, eaq- and some one-electron oxidants have been studied with salicylic acid and 5-sulpho-salicylic acid in aqueous solutions. Rate constants for the reaction of eaq- with these compounds were of the order of 109dm3mol-1s-1 and this reaction led to the formation of reducing radicals which could transfer electron to methyl viologen. Other one-electron reductants were not able to reduce these compounds. OH radicals reacted with these compounds by addition pathway with very high rate constants (>1010dm3mol-1s-1) while O- radical anions could oxidize these molecules to give phenoxyl type of radicals. Amongst the one-electron oxidants, only N3 radicals and SO4- radicals could oxidize salicylic acid while 5-sulpho-salicylic acid could be oxidized only by SO4- radicals indicating that while one-electron reduction potential for semi-oxidized SA may beo1 for N3? radical), it is more than 1.33V vs. NHE for semi-oxidized SSA species

  17. The IUPAC aqueous and non-aqueous experimental pKa data repositories of organic acids and bases.

    Science.gov (United States)

    Slater, Anthony Michael

    2014-10-01

    Accurate and well-curated experimental pKa data of organic acids and bases in both aqueous and non-aqueous media are invaluable in many areas of chemical research, including pharmaceutical, agrochemical, specialty chemical and property prediction research. In pharmaceutical research, pKa data are relevant in ligand design, protein binding, absorption, distribution, metabolism, elimination as well as solubility and dissolution rate. The pKa data compilations of the International Union of Pure and Applied Chemistry, originally in book form, have been carefully converted into computer-readable form, with value being added in the process, in the form of ionisation assignments and tautomer enumeration. These compilations offer a broad range of chemistry in both aqueous and non-aqueous media and the experimental conditions and original reference for all pKa determinations are supplied. The statistics for these compilations are presented and the utility of the computer-readable form of these compilations is examined in comparison to other pKa compilations. Finally, information is provided about how to access these databases.

  18. Neodymium(3) complexing with bischloromethylphosphinic acid in aqueous solution

    International Nuclear Information System (INIS)

    High resolution spectrography is used to study Nd3+ complexing with (ClCH2)2POOH(HL) in aqueous solution. NdL2+ complex (lg Kstab = 0.44±0.04) with the corresponding absorption band with a maximum at λ=4283 A is formed in a system

  19. Kinetic multi-layer model of aerosol surface and bulk chemistry (KM-SUB: the influence of interfacial transport and bulk diffusion on the oxidation of oleic acid by ozone

    Directory of Open Access Journals (Sweden)

    M. Shiraiwa

    2010-04-01

    Full Text Available We present a novel kinetic multi-layer model that explicitly resolves mass transport and chemical reaction at the surface and in the bulk of aerosol particles (KM-SUB. The model is based on the PRA framework of gas-particle interactions (Pöschl-Rudich-Ammann, 2007, and it includes reversible adsorption, surface reactions and surface-bulk exchange as well as bulk diffusion and reaction. Unlike earlier models, KM-SUB does not require simplifying assumptions about steady-state conditions and radial mixing. The temporal evolution and concentration profiles of volatile and non-volatile species at the gas-particle interface and in the particle bulk can be modeled along with surface concentrations and gas uptake coefficients.

    In this study we explore and exemplify the effects of bulk diffusion on the rate of reactive gas uptake for a simple reference system, the ozonolysis of oleic acid particles, in comparison to experimental data and earlier model studies. We demonstrate how KM-SUB can be used to interpret and analyze experimental data from laboratory studies, and how the results can be extrapolated to atmospheric conditions. In particular, we show how interfacial and bulk transport, i.e., surface accommodation, bulk accommodation and bulk diffusion, influence the kinetics of the chemical reaction. Sensitivity studies suggest that in fine air particulate matter oleic acid and compounds with similar reactivity against ozone (carbon-carbon double bonds can reach chemical lifetimes of many hours only if they are embedded in a (semi-solid matrix with very low diffusion coefficients (≤10−10 cm2 s−1. Depending on the complexity of the investigated system, unlimited numbers of volatile and non-volatile species and chemical reactions can be flexibly added and treated with KM-SUB. We propose and intend to pursue the application of KM-SUB as a basis for the development of a detailed master mechanism of aerosol

  20. Kinetic multi-layer model of aerosol surface and bulk chemistry (KM-SUB: the influence of interfacial transport and bulk diffusion on the oxidation of oleic acid by ozone

    Directory of Open Access Journals (Sweden)

    M. Shiraiwa

    2010-01-01

    Full Text Available We present a novel kinetic multi-layer model that explicitly resolves mass transport and chemical reaction at the surface and in the bulk of aerosol particles (KM-SUB. The model is based on the PRA framework of gas-particle interactions (Pöschl et al., 2007, and it includes reversible adsorption, surface reactions and surface-bulk exchange as well as bulk diffusion and reaction. Unlike earlier models, KM-SUB does not require simplifying assumptions about steady-state conditions and radial mixing. The temporal evolution and concentration profiles of volatile and non-volatile species at the gas-particle interface and in the particle bulk can be modeled along with surface concentrations and gas uptake coefficients.

    In this study we explore and exemplify the effects of bulk diffusion on the rate of reactive gas uptake for a simple reference system, the ozonolysis of oleic acid particles, in comparison to experimental data and earlier model studies. We demonstrate how KM-SUB can be used to interpret and analyze experimental data from laboratory studies, and how the results can be extrapolated to atmospheric conditions. In particular, we show how interfacial transport and bulk transport, i.e., surface accommodation, bulk accommodation and bulk diffusion, influence the kinetics of the chemical reaction. Sensitivity studies suggest that in fine air particulate matter oleic acid and compounds with similar reactivity against ozone (C=C double bonds can reach chemical lifetimes of multiple hours only if they are embedded in a (semi-solid matrix with very low diffusion coefficients (≤10−10 cm2 s−1.

    Depending on the complexity of the investigated system, unlimited numbers of volatile and non-volatile species and chemical reactions can be flexibly added and treated with KM-SUB. We propose and intend to pursue the application of KM-SUB as a basis for the development of a detailed master mechanism of

  1. Change in the amino acid composition of calf skin collagen after. gamma. -irradiation in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Duzhenkova, N.A.; Savich, A.V. (Institut Biofiziki, Moscow (USSR))

    A study was made of the amino acid composition of calf skin collagen after ..gamma..-irradiation (/sup 60/Co) of 2.5x10/sup -6/ M aerated aqueous protein solution within the dose range from 30 to 2000 Gy. The radiosensitivity of amino acid residues was compared.

  2. Rosmarinic acid content in antidiabetic aqueous extract of Ocimum canum Sims grown in Ghana

    Science.gov (United States)

    Rosmarinic acid (RA) is an important polyphenol that is found in a variety of herbs including Ocimum canum sims (locally called eme or akokobesa in Ghana). Aqueous extracts from the leaves of O.canum are used as an antidiabetic herbal medicine in Ghana. Interestingly, rosmarinic acid content and p...

  3. Self-assembly and foaming properties of fatty acid-lysine aqueous dispersions.

    Science.gov (United States)

    Novales, Bruno; Riaublanc, Alain; Navailles, Laurence; Houssou, Bérénice Houinsou; Gaillard, Cédric; Nallet, Frédéric; Douliez, Jean-Paul

    2010-04-20

    We report on dispersions of fatty acid-lysine salts in aqueous solutions which are further used to produce foams. The alkyl chain length is varied from dodecyl to stearic. In aqueous solutions, the lysine salt of the dodecyl chain yields an isotropic solution, probably micelles, whereas for longer alkyl chains, vesicles formed but crystallized upon resting at room temperature or when kept at 4 degrees C. Solid-state NMR showed that in vesicles fatty acids are embedded in a lamellar arrangement passing from a gel to a fluid state upon heating; the transition temperature at which it occurs was determined by DSC. Those results are confirmed by small-angle neutron scattering which also give additional information on the bilayer structure. Incredibly stable foams are obtained using the palmitic acid/Lys salt whereas for other alkyl chain length, poor or no foam is formed. We conclude that the foamability is related to the phase behavior in aqueous solution. PMID:20334439

  4. Improvement in Aqueous Solubility of Retinoic Acid Receptor (RAR) Agonists by Bending the Molecular Structure.

    Science.gov (United States)

    Hiramatsu, Michiaki; Ichikawa, Yuki; Tomoshige, Shusuke; Makishima, Makoto; Muranaka, Atsuya; Uchiyama, Masanobu; Yamaguchi, Takao; Hashimoto, Yuichi; Ishikawa, Minoru

    2016-08-01

    Aqueous solubility is a key requirement for many functional molecules, e. g., drug candidates. Decrease of the partition coefficient (log P) by chemical modification, i.e., introduction of hydrophilic group(s) into molecules, is a classical strategy for improving aqueous solubility. We have been investigating alternative strategies for improving the aqueous solubility of pharmaceutical compounds by disrupting intermolecular interactions. Here, we show that introducing a bend into the molecular structure of retinoic acid receptor (RAR) agonists by changing the substitution pattern from para to meta or ortho dramatically enhances aqueous solubility by up to 890-fold. We found that meta analogs exhibit similar hydrophobicity to the parent para compound, and have lower melting points, supporting the idea that the increase of aqueous solubility was due to decreased intermolecular interactions in the solid state as a result of the structural changes. PMID:27378357

  5. Comparative analysis of the effect of pretreating aspen wood with aqueous and aqueous-organic solutions of sulfuric and nitric acid on its reactivity during enzymatic hydrolysis

    DEFF Research Database (Denmark)

    Dotsenko, Gleb; Osipov, D. O.; Zorov, I. N.;

    2016-01-01

    The effect of aspen wood pretreatment methods with the use of both aqueous solutions of sulfuric and nitric acids and aqueous-organic solutions (ethanol, butanol) of sulfuric acid (organosolv) on the limiting degree of conversion of this type of raw material into simple sugars during enzymatic...... of ground wood by 300–400%, compared to the initial raw material. Pretreatment with a 4.8% aqueous solution of nitric acid (125°C, 1.8 MPa, 10 min) is shown to be most effective, as it increases the reactivity of the ground aspen wood by more than 500%....

  6. Versatile electrochemical coatings and surface layers from aqueous methanesulfonic acid

    OpenAIRE

    Walsh, F. C.; Ponce De Leon, Carlos

    2014-01-01

    Ever tightening environmental pressure together with the continued need for coatings able to meet challenging service environments have stimulated advances in coating technology. In the case of electrochemical techniques, the classical techniques of electrodeposition and anodising are being upgraded to meet the need for modern surface engineering coatings (including nanostructured films) on metals. A major challenge is to retain conventional processing, including aqueous solutions, simple pow...

  7. EFFECT OF TEMPERATURE AND CONCENTRATION ON THE VISCOSITY OF AQUEOUS SOLUTIONS OF 3-AMINOPROPANOIC ACID, 4-AMINOBUTANOIC ACID, 5-AMINOPENTANOIC ACID, 6-AMINOHEXANOIC ACID

    Directory of Open Access Journals (Sweden)

    Carmen María Romero

    2011-12-01

    Full Text Available In this work we present the effect of temperatureon the viscosities of aqueous solutionsof 3-aminopropanoic acid, 4-aminobutanoicacid, 5-aminopentanoic acidand 6-aminohexanoic acid as a functionof concentration. The experimental measurementswere done from 293.15 K to308.15 K. At each temperature the experimentaldata were fi tted to the Tsangaris-Martin equation and the B viscosity coefficient was determined. The dependenceof the B coeffi cients on the number ofcarbon atoms of the amino acids is linear,so the contribution of polar and apolargroups was established. The results areinterpreted in terms of amino acid hydration.

  8. Radiation-thermal decomposition of nitric and acetic acids in the aqueous nitrate solution

    International Nuclear Information System (INIS)

    Kinetics of radiation, thermal and radiation-thermal decompositions of nitric and acetic acid mixture was investigated in aqueous sodium nitrate solution in homogeneous conditions as well as by interaction of solid phase as sand rock. Temperature dependences of rate of radiation, thermal and radiation-thermal decompositions of the acids were calculated using experimental data. Resulting solutions make possible the calculation of acid decomposition dynamics accounting conditions of underground radioactive waste disposals

  9. Kinetics of oxidation of ethyldigol by vanadium(V) in aqueous acidic medium

    International Nuclear Information System (INIS)

    The kinetics of oxidation of ethyldigol by vanadium(V) in aqueous acidic medium has been carried out. The reaction is first order with respect to vanadium(V) and the substrate and is acid catalysed. Hammett acidity function (H0) and Bunnett hypothesis have been applied. The formation of free radicals during the course of the reaction has been indicated. A probable reaction mechansim is proposed. (Author)

  10. V-型直链淀粉-油酸复合物的制备与结构表征%The preparation and characterization of V-type amylose-oleic acid complex

    Institute of Scientific and Technical Information of China (English)

    钱志伟; 杨留枝; 秦令祥; 李红; 李学红; 申瑞玲; 刘延奇

    2011-01-01

    B-type microcrystal starch was dissolved in DMSO and dispersed in the hot water.Then added a certain proportion of the oleic acid and alcohol,then the complexes were mixed,crystallized,centrifuged,washed,the amylose-were acquired.SEM,X-ray diffractometer,%以B-型微晶淀粉为原料,经二甲亚砜溶解后,分散至热水中,加入一定比例的油酸的乙醇溶液中,经过高温混合、结晶、离心分离、洗涤,制得淀粉-油酸复合物。采用扫描电子显微镜、X-射线衍射仪、红外光谱和DSC对得到的复合物进行分析和测试,结果表明:复合物颗粒直径约为2μm,X-射线衍射图形为典型的V-型结构,红外光谱中显示出了油酸复合物的相关特征,DSC分析表明V-型复合物的稳定性小于B-型微晶淀粉。

  11. Gomisin J Inhibits Oleic Acid-Induced Hepatic Lipogenesis by Activation of the AMPK-Dependent Pathway and Inhibition of the Hepatokine Fetuin-A in HepG2 Cells.

    Science.gov (United States)

    Kim, Myungsuk; Lim, Sue Ji; Lee, Hee-Ju; Kim, Sun Young; Nho, Chu Won

    2015-11-11

    The aim of our study is to investigate the molecular mechanism of gomisin J from Schisandra chinensis on the oleic acid (OA)-induced lipid accumulation in HepG2 cells. Gomisin J attenuated lipid accumulation in OA-induced HepG2 cells. It also suppressed the expression of lipogenic enzymes and inflammatory mediators and increased the expression of lipolytic enzymes in OA-induced HepG2 cells. Furthermore, the use of specific inhibitors and fetuin-A siRNA and liver kinase B1 (LKB1) siRNA transfected cells demonstrated that gomisin J regulated lipogenesis and lipolysis via inhibition of fetuin-A and activation of an AMP-activated protein kinase (AMPK)-dependent pathway in HepG2 cells. Our results showed that gomisin J suppressed lipid accumulation by regulating the expression of lipogenic and lipolytic enzymes and inflammatory molecules through activation of AMPK, LKB1, and Ca(2+)/calmodulin-dependent protein kinase II and inhibition of fetuin-A in HepG2 cells. This suggested that gomisin J has potential benefits in treating nonalcoholic fatty liver disease.

  12. 油酸/氨水-醇-汽油-水微乳体系拟三元相图的分析%Analysis on the phase diagrams of pseudo-tricomponent of oleic acid/ammonia-gasoline-alcohol-water microemulsion system

    Institute of Scientific and Technical Information of China (English)

    张强; 汪晓东; 金日光

    2001-01-01

    The phase diagrams of pseudo-tricomponent of microemulsions consisting of oleic acid/ammonia-gasoline-alcohol-water were plotted, and the properties of this microemulsion system were discussed. It was found that the size of microemulsion regions and maximum water content of microemulsion were related to the kinds of alcohols, in which the n-butanol had the largest size of microemulsion regions and maximum water content of microemulsions. In addition, with the content of gasoline and environmental temperature increased, the size of microemulsion regions and maximum water content of microemulsions decreased.%制备了油酸/氨水-汽油-醇-水微乳液系列,并采用拟三元相图对此微乳体系进行了研究.结果表明,助表面活性剂醇的种类对微乳汽油的微乳区面积及水最大增溶量具有很大影响,其中正丁醇体系的微乳区面积及水的增溶量最大.另外体系中汽油含量增大及环境温度的升高均导致体系微乳区面积和水增溶量的减小.

  13. Oleic acid loading does not add to the nephrotoxic effect of albumin in an amphibian and chronic rat model of kidney injury

    NARCIS (Netherlands)

    van Timmeren, Mirjan M.; Gross, Marie-Luise; Hanke, Wilfried; Klok, Pieter A.; van Goor, Harry; Stegeman, Coen A.; Bakker, Stephan J. L.

    2008-01-01

    Background. Under proteinuric conditions, ultrafiltrated albumin can induce an inflammatory and fibrotic response in proximal tubular cells. It is unclear whether albumin per se or compounds bound to albumin are nephrotoxic. Some studies have supported the toxicity of albumin-bound fatty acids; howe

  14. Regulation of serum-responsive transmembrane kinase EhTMKB1-9 by an unsaturated lipid, oleic acid in protistan parasite Entamoeba histolytica.

    Science.gov (United States)

    Saha, Arpita; Bhattacharya, Sudha; Bhattacharya, Alok

    2014-11-01

    Transmembrane kinases of Entamoeba histolytica are known to play a wide range of roles from virulence, phagocytosis, and proliferation to stress response. Transmembrane kinase EhTMKB1-9 is thought to be involved in early proliferative response and it was originally identified as a serum inducible gene. Ability to stimulate EhTMKB1 expression of serum starved cells resides in unsaturated fatty acids associated with albumin fraction of serum and the mechanism of stimulation follows activation of EhTMKB1-9 promoter. Gel shift assay showed the presence of proteins that bind to the specific site of EhTMKB1-9 upstream region and the concentration of these protein(s) go down on serum starvation, but level of binding protein(s) go up on serum or fatty acid replenishment. This increase in concentration of binding molecule(s) is due to new synthesis rather than activation of existing molecule(s) as a protein synthesis inhibitor blocked enhanced level of gel shifted material on replenishment. The stimulating activity resides in the fatty acyl chain, but not in the head group. Moreover, the fatty acid initiates signaling through class I PI3 kinases that result in activation of EhTMKB1-9 expression. These results suggest a novel mechanism of gene regulation in E. histolytica, and unsaturated fatty acids as potential new signaling molecules.

  15. Phosphorylation of glyceric acid in aqueous solution using trimetaphosphate.

    Science.gov (United States)

    Kolb, V; Orgel, L E

    1996-02-01

    The phosphorylation of glyceric acid is an interesting prebiotic reaction because it converts a simple, potentially prebiotic organic molecule into phosphate derivatives that are central to carbohydrate metabolism. We find that 0.05 M glyceric acid in the presence of 0.5 M trimetaphosphate in alkaline solution gives a mixture of 2- and 3-phosphoglyceric acids in combined yields of up to 40%. PMID:11536746

  16. Phosphorylation of Glyceric Acid in Aqueous Solution Using Trimetaphosphate

    Science.gov (United States)

    Kolb, Vera; Orgel, Leslie E.

    1996-01-01

    The phosphorylation of glyceric acid is an interesting prebiotic reaction because it converts a simple, potentially prebiotic organic molecule into phosphate derivatives that are central to carbohydrate metabolism. We find that 0.05 M glyceric acid in the presence of 0.5 M trimetaphosphate in alkaline solution gives a mixture of 2- and 3-phosphoglyceric acids in combined yields of up to 40%.

  17. Effects of organic acids, amino acids and ethanol on the radio-degradation of patulin in an aqueous model system

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyejeong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Department of Food Science and Technology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lim, Sangyong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Jo, Cheorun [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Chung, Jinwoo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Kim, Soohyun [Glycomics Team, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Kwon, Joong-Ho [Department of Food Science and Technology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Dongho [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of)], E-mail: fungikim@kaeri.re.kr

    2008-06-15

    The effects of organic acids, amino acids, and ethanol on the radio-degradation of patulin by gamma irradiation in an aqueous model system were investigated. The patulin, dissolved in distilled water at a concentration of 50 ppm, was practically degraded by the gamma irradiation at the dose of 1.0 kGy, while 33% of the patulin remained in apple juice. In the aqueous model system, the radio-degradation of patulin was partially inhibited by the addition of organic acids, amino acids, and ethanol. The proportions of remaining patulin after irradiation with the dose of 1.0 kGy in the 1% solution of malic acid, citric acid, lactic acid, acetic acid, ascorbic acid, and ethanol were 31.4%, 2.3%, 31.2%, 6.1%, 50.8%, and 12.5%, respectively. During 30 days of storage, the remaining patulin was reduced gradually in the solution of ascorbic acid and malic acid compared to being stable in other samples. The amino acids, serine, threonine, and histidine, inhibited the radio-degradation of patulin. In conclusion, it was suggested that 1 kGy of gamma irradiation (recommended radiation doses for radicidation and/or quarantine in fruits) is effective for the reduction of patulin, but the nutritional elements should be considered because the radio-degradation effects are environment dependent.

  18. Adsorption of organic acids from dilute aqueous solution onto activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.W.

    1980-06-01

    The radioisotope technique was used to study the removal of organic acid contaminants from dilute aqueous solutions onto activated carbon. Acetic acid, propionic acid, n-butyric acid, n-hexanoic acid and n-heptanoic acid were studied at 278, 298, and 313/sup 0/K. Three bi-solute acid mixtures (acetic and propionic acids, acetic and butanoic acids, and propionic and butanoic acids) were studied at 278 and 298/sup 0/K. Isotherms of the single-solute systems were obtained at three different temperatures in the very dilute concentration region (less than 1% by weight). These data are very important in the prediction of bi-solute equilibrium data. A Polanyi-based competitive adsorption potential theory was used to predict the bi-solute equilibrium uptakes. Average errors between calculated and experimental data ranges from 4% to 14%. It was found that the competitive adsorption potential theory gives slightly better results than the ideal adsorbed solution theory.

  19. Electrical conductivity of aqueous solutions of perrhenic acid

    International Nuclear Information System (INIS)

    The physiocochemical properties of perrhenic acid, HReO4, are studied; its salts form the basis of solutions for electrochemical production of rhenium. Information is presented from which the electrical conductivity of solutions in the temperature range 15-90 degrees can be determined from known concentrations of the acid in water and vice versa

  20. Aqueous citric acid as green reaction media for the synthesis of octahydroxanthenes

    Directory of Open Access Journals (Sweden)

    Camilo A. Navarro D.

    2013-08-01

    Full Text Available A simple, convenient and environmentally friendly one-pot procedure for the synthesis of 1,8-dioxo-octahydroxanthenes by the reaction of dimedone and aromatic aldehydes in aqueous citric acid is described. In this green synthetic protocol promoted by the reaction media, the use of any other catalysts and hazardous organic solvents are avoided, making the work up procedure greener and easier. The isolation of the products, obtained in good yields, is readily performed by filtration and crystallization from ethanol when required and the aqueous acidic media can be easily recycled and reused several times without significant loss of catalytic activity.

  1. Multi-walled carbon nanotubes in aqueous phytic acid for enhancing biosensor

    International Nuclear Information System (INIS)

    The poor dispersion of carbon based nanomaterials without strong acid pretreatment in aqueous solution is a fundamental problem, limiting its applications in biology-related fields. A good dispersion of multi-walled carbon nanotubes (MWCNTs) in water was realized by 50 wt.% phytic acid (PA) solution. As an application case, the PA–MWCNTs dispersion in aqueous solution was used for the immobilization of horseradish peroxidase (HRP) and its direct electrochemistry was realized. The constructed biosensor has a sound limit of detection, wide linear range, and high affinity for hydrogen peroxide (H2O2) as well as being free from interference of co-existing electro-active species. (papers)

  2. Multi-walled carbon nanotubes in aqueous phytic acid for enhancing biosensor

    Science.gov (United States)

    Guo, Xiaoyu; Miao, Yun; Ye, Pingping; Wen, Ying; Yang, Haifeng

    2014-04-01

    The poor dispersion of carbon based nanomaterials without strong acid pretreatment in aqueous solution is a fundamental problem, limiting its applications in biology-related fields. A good dispersion of multi-walled carbon nanotubes (MWCNTs) in water was realized by 50 wt.% phytic acid (PA) solution. As an application case, the PA-MWCNTs dispersion in aqueous solution was used for the immobilization of horseradish peroxidase (HRP) and its direct electrochemistry was realized. The constructed biosensor has a sound limit of detection, wide linear range, and high affinity for hydrogen peroxide (H2O2) as well as being free from interference of co-existing electro-active species.

  3. Dissolution state of cellulose in aqueous systems. 2. Acidic solvents.

    Science.gov (United States)

    Alves, Luis; Medronho, Bruno; Antunes, Filipe E; Topgaard, Daniel; Lindman, Björn

    2016-10-20

    Cellulose is insoluble in water but can be dissolved in strong acidic or alkaline conditions. How well dissolved cellulose is in solution and how it organizes are key questions often neglected in literature. The typical low pH required for dissolving cellulose in acidic solvents limits the use of typical characterization techniques. In this respect, Polarization Transfer Solid State NMR (PT ssNMR) emerges as a reliable alternative. In this work, combining PT ssNMR, microscopic techniques and X-ray diffraction, a set of different acidic systems (phosphoric acid/water, sulfuric acid/glycerol and zinc chloride/water) is investigated. The studied solvent systems are capable to efficiently dissolve cellulose, although degradation occurs to some extent. PT ssNMR is capable to identify the liquid and solid fractions of cellulose, the degradation products and it is also sensitive to gelation. The materials regenerated from the acidic dopes were found to be highly sensitive to the solvent system and to the presence of amphiphilic additives in solution. PMID:27474617

  4. Aqueous solutions of acidic ionic liquids for enhanced stability of polyoxometalate-carbon supercapacitor electrodes

    Science.gov (United States)

    Hu, Chenchen; Zhao, Enbo; Nitta, Naoki; Magasinski, Alexandre; Berdichevsky, Gene; Yushin, Gleb

    2016-09-01

    Nanocomposites based on polyoxometalates (POMs) nanoconfined in microporous carbons have been synthesized and used as electrodes for supercapacitors. The addition of the pseudocapacitance from highly reversible redox reaction of POMs to the electric double-layer capacitance of carbon lead to an increase in specific capacitance of ∼90% at 1 mV s-1. However, high solubility of POM in traditional aqueous electrolytes leads to rapid capacity fading. Here we demonstrate that the use of aqueous solutions of protic ionic liquids (P-IL) as electrolyte instead of aqueous sulfuric acid solutions offers an opportunity to significantly improve POM cycling stability. Virtually no degradation in capacitance was observed in POM-based positive electrode after 10,000 cycles in an asymmetric capacitor with P-IL aqueous electrolyte. As such, POM-based carbon composites may now present a viable solution for enhancing energy density of electrical double layer capacitors (EDLC) based on pure carbon electrodes.

  5. SFH2 regulates fatty acid synthase activity in the yeast Saccharomyces cerevisiae and is critical to prevent saturated fatty acid accumulation in response to haem and oleic acid depletion

    OpenAIRE

    Desfougères, Thomas; Ferreira, Thierry; Bergès, Thierry; Régnacq, Matthieu

    2007-01-01

    Abstract The yeast Saccharomyces cerevisiae is a facultative anaerobic organism. In anaerobiosis, sustained growth relies on the presence of exogenously supplied unsaturated fatty acids and ergosterol that yeast is unable to synthesize in the absence of oxygen or upon haem depletion. In the absence of exogenous supplementation with unsaturated fatty acid, a net accumulation of saturated fatty acid (SFA) is observed that induces significant modification of phospholipid profile [1]. ...

  6. Boron removal from aqueous solutions by activated carbon impregnated with salicylic acid

    International Nuclear Information System (INIS)

    In this study, the removal of boric acid from aqueous solution by activated carbon impregnated with salicylic acid was studied in batch system. pH, adsorbent amount, initial boron concentration, temperature, shaking rate and salicylic acid film thickness were chosen as parameters. Boron removal efficiencies increased with increasing adsorbent amount, temperature and pH, decreasing initial boron concentration. As thickness of salicylic acid film on activated carbon becomes thin up to 0.088 nm, the efficiency increased, and then, the efficiency decreased with becoming thinner than 0.088 nm of salicylic acid film. Shaking rate was no effect on removal efficiency. In result, it was determined that the use of salicylic acid as an impregnant for activated carbon led to the increase of the amount of boron adsorbed. A lactone ring, being the most appropriate conformation, forms between boric acid and -COOH and -OH groups of salicylic acid

  7. Uptake of hypobromous acid (HOBr by aqueous sulfuric acid solutions: low-temperature solubility and reaction

    Directory of Open Access Journals (Sweden)

    L. T. Iraci

    2005-03-01

    Full Text Available Hypobromous acid (HOBr is a key species linking inorganic bromine to the chlorine and odd hydrogen chemical families. We have measured the solubility of HOBr in 45–70 wt% sulfuric acid solutions representative of upper tropospheric and lower stratospheric aerosol composition. Over the temperature range 201–252 K, HOBr is quite soluble in sulfuric acid, with an effective Henry's law coefficient, H*=104-107 mol L-1 atm-1. H* is inversely dependent on temperature, with ΔH=-45.0±5.4 kJ mol-1 and ΔS=-101±24 J mol-1 K-1 for 55–70 wt% H2SO4 solutions. Our study includes temperatures which overlap both previous measurements of HOBr solubility. For uptake into 55–70 wt% H2SO4, the solubility is described by log H*=(2349±280/T–(5.27±1.24. At temperatures colder than ~213 K, the solubility of HOBr in 45 wt% H2SO4 is at least a factor of five larger than in 70 wt% H2SO4, with log H*=(3665±270/T–(10.63±1.23. The solubility of HOBr is comparable to that of HBr, indicating that upper tropospheric and lower stratospheric aerosols should contain equilibrium concentrations of HOBr which equal or exceed those of HBr. Upon uptake of HOBr into aqueous sulfuric acid in the presence of other brominated gases, particularly for 70 wt% H2SO4 solution, our measurements demonstrate chemical reaction of HOBr followed by evolution of gaseous products including Br2O and Br2.

  8. Chemical modification of amino acids by atmospheric-pressure cold plasma in aqueous solution

    Science.gov (United States)

    Takai, Eisuke; Kitamura, Tsuyoshi; Kuwabara, Junpei; Ikawa, Satoshi; Yoshizawa, Shunsuke; Shiraki, Kentaro; Kawasaki, Hideya; Arakawa, Ryuichi; Kitano, Katsuhisa

    2014-07-01

    Plasma medicine is an attractive new research area, but the principles of plasma modification of biomolecules in aqueous solution remain elusive. In this study, we investigated the chemical effects of atmospheric-pressure cold plasma on 20 naturally occurring amino acids in aqueous solution. High-resolution mass spectrometry revealed that chemical modifications of 14 amino acids were observed after plasma treatment: (i) hydroxylation and nitration of aromatic rings in tyrosine, phenylalanine and tryptophan; (ii) sulfonation and disulfide linkage formation of thiol groups in cysteine; (iii) sulfoxidation of methionine and (iv) amidation and ring-opening of five-membered rings in histidine and proline. A competitive reaction experiment using 20 amino acids demonstrated that sulfur-containing and aromatic amino acids were preferentially decreased by the plasma treatment. These data provide fundamental information for elucidating the mechanism of protein inactivation for biomedical plasma applications.

  9. Interaction between N-Phospho-Amino Acids and Nucleoside in Aqueous Medium

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Nucleosides were phosphorylated with different N- (O, O-diisopropyl) phosphoryl amino acids to give nucleoside mono phosphates in aqueous solution. 2', 3', and 5'-isomers had been confirmed by comparison with authentic samples on the basis of HPLC analysis. The conversion percentage of nucleoside indicated that N- (O, O-diisopropyl) phosphoryl aspartic acid reacted with adenosine and guanosine at a much higher rate than other kinds of N- phosphoryl amino acids, while phosphorylation of cytidine and uridine was relatively easy by using N- (O, O-diisopropyl) phosphoryl threonine. The result could give some clue to the prebiotic code origin of nucleic acid and protein.

  10. Characterization of a riboflavin non-aqueous nanosuspension prepared by bead milling for cutaneous application.

    Science.gov (United States)

    Sato, Takayuki; Takeuchi, Hiroyuki; Sakurai, Takanobu; Tanaka, Kensuke; Matsuki, Kota; Higashi, Kenjirou; Moribe, Kunikazu; Yamamoto, Keiji

    2015-01-01

    The purpose of this study was to characterize the non-aqueous nanosuspension of a hydrophilic drug prepared by bead milling for cutaneous application. Riboflavin was used as the model hydrophilic drug. The non-aqueous nanosuspensions were prepared by grinding riboflavin with zirconia beads using eight non-aqueous bases. The mean particle size of riboflavin in the suspensions ranged from 206 to 469 nm, as determined by the dynamic light scattering method. Among the well-dispersed samples, riboflavin nanosuspension prepared in oleic acid was selected for evaluation of the drug permeability through rat skin. The cumulative amount and permeation rate of riboflavin from the nanosuspension were approximately three times higher than those for unprocessed riboflavin in oleic acid. Fluorescence imaging of the riboflavin nanosuspension suggested improved penetration of riboflavin into the stratum corneum. Furthermore, the addition of polysorbate 65 or polyglyceryl-6 polyricinoleate to the nanosuspension prepared in oleic acid markedly improved the riboflavin dispersibility. These results show that the preparation of a nanosuspension in a non-aqueous base by bead milling is one of the simple methods to improve the skin permeability of hydrophilic drugs. PMID:25748779

  11. Thermal decomposition of dilute aqueous formic acid solutions

    DEFF Research Database (Denmark)

    Bjerre, A.B.; Sørensen, E.

    1992-01-01

    or a decarboxylation. In particular the second one is dependent on the reactor vessel used. It is shown to be catalyzed by a mixture of oxides of stainless steel components. The presence of CH3COOH or CH3CHO promotes the decomposition of HCOOH by way of both decarboxylation and oxidation. In any case formic acid...

  12. Salt dependent stability of stearic acid Langmuir-Blodgett films exposed to aqueous electrolytes

    NARCIS (Netherlands)

    Kumar, Naveen; Wang, Lei; Siretanu, Igor; Duits, Michel; Mugele, Frieder

    2013-01-01

    We use contact angle goniometry, imaging ellipsometry, and atomic force microscopy to study the stability and wettability of Langmuir–Blodgett (LB) monolayers of stearic acid on silica substrates, upon drying and exposure to aqueous solutions of varying salinity. The influences of Ca2+ and Na+ ions

  13. Diffusion Coefficient and Solubility of Isobutene and trans-2-Butene in Aqueous Sulfuric Acid Solutions

    NARCIS (Netherlands)

    Brilman, Derk W.F.; Swaaij, Wim P.M. van; Versteeg, Geert F.

    2001-01-01

    The diffusion coefficient and the physical solubility of isobutene and trans-2-butene in aqueous sulfuric acid solutions cannot be determined experimentally due to the occurrence of fast chemical reactions. In the present contribution these physicochemical parameters are estimated. For the solubilit

  14. Aqueous-phase hydrogenation of acetic acid over transition metal catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Olcay, Hakan [University of Massachusetts, Amherst; Xu, Lijun [ORNL; Xu, Ye [ORNL; Huber, George [University of Massachusetts, Amherst

    2010-01-01

    Catalytic hydrogenation of acetic acid to ethanol has been carried out in aqueous phase on several metals, with ruthenium being the most active and selective. DFT calculations suggest that the initial CO bond scission yielding acetyl is the key step and that the intrinsic reactivity of the metals accounts for the observed activity.

  15. Kinetic study of CO2 with various amino acid salts in aqueous solution

    NARCIS (Netherlands)

    Holst, van J.; Versteeg, G.F.; Brilman, D.W.F.; Hogendoorn, J.A.

    2009-01-01

    A study towards the kinetics of CO2 with several aqueous salts of amino acids was performed at a temperature of 298 K. Absorption rate experiments were carried out in the pseudo-first-order regime, enabling the determination of the kinetic rate constant from the flux. In a preliminary screening at a

  16. Kinetic study of CO2 with various amino acid salts in aqueous solution

    NARCIS (Netherlands)

    van Hoist, J.; Versteeg, G. F.; Brilman, D. W. F.; Hogendoorn, J. A.; Holst, J. v

    2009-01-01

    A study towards the kinetics Of CO2 with several aqueous salts of amino acids was performed at a temperature of 298 K. Absorption rate experiments were carried out in the pseudo-first-order regime, enabling the determination of the kinetic rate constant from the flux. In a preliminary screening at a

  17. Rosmarinic acid content in antidiabetic aqueous extract from ocimum canum sims in Ghana

    Science.gov (United States)

    Rosmarinic acid (RA) is an important polyphenol that is found in a variety of herbs including Ocimum canum sims (locally called eme or akokobesa in Ghana). Aqueous extracts from the leaves of O. canum are used as an antidiabetic herbal medicine in Ghana. Analytical TLC was used to examine the compos...

  18. 49 CFR 173.195 - Hydrogen cyanide, anhydrous, stabilized (hydrocyanic acid, aqueous solution).

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Hydrogen cyanide, anhydrous, stabilized... Hazardous Materials Other Than Class 1 and Class 7 § 173.195 Hydrogen cyanide, anhydrous, stabilized (hydrocyanic acid, aqueous solution). (a) Hydrogen cyanide, anhydrous, stabilized, must be packed...

  19. Standard enthalpies of formation of α-aminobutyric acid and products of its dissociation in an aqueous solution

    Science.gov (United States)

    Lytkin, A. I.; Chernikov, V. V.; Krutova, O. N.

    2016-08-01

    Heats of solution of crystalline α-aminobutyric acid in water and in aqueous solutions of potassium hydroxide at 298.15 K are measured by means of direct calorimetry. Standard enthalpies of formation of the amino acid and products of its dissociation in an aqueous solution are calculated.

  20. FT-RAMAN SPECTROSCOPY FOR MONITORING THE POLYMERIZATION OF ACRYLIC ACID IN AQUEOUS SOLUTION

    Institute of Scientific and Technical Information of China (English)

    Jiang Yu; Hui-zhou Liu; Jia-yong Chen

    1999-01-01

    FT-Raman spectroscopy was used to monitor the polymerization of acrylic acid in aqueous solution. A simple method to avoid the noise in the background during the signal processing via Fourier transformation was used in this work. The effects of the amount of initiator used on the polymerization are studied. When the amount of the initiator in the polymerization was increased, both the rate and extent of polymerization of acrylic acid will be increased.

  1. Removal of Aqueous Boron by Using Complexation of Boric Acid with Polyols: A Raman Spectroscopic Study

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Ki Heon; Jeong, Hui Cheol; An, Hye Young; Lim, Jun-Heok; Lee, Jea-Keun; Won, Yong Sun [Pukyong National University, Busan (Korea, Republic of)

    2015-12-15

    Boron is difficult to be removed from seawater by simple RO (reverse osmosis) membrane process, because the size of boric acid (B(OH){sub 3}), the major form of aqueous boron, is as small as the nominal pore size of RO membrane. Thus, the complexation of boric acid with polyols was suggested as an alternative way to increase the size of aqueous boron compounds and the complexation behavior was investigated with Raman spectroscopy. As a reference, the Raman peak for symmetric B-O stretching vibrational mode both in boric acid and borate ion (B(OH){sub 4}{sup -}) was selected. A Raman peak shift (877 cm{sup -1} →730 cm{sup -1}) was observed to confirm that boric acid in water is converted to borate ion as the pH increases, which is also correctly predicted by frequency calculation. Meanwhile, the Raman peak of borate ion (730 cm{sup -1}) did not appear as the pH increased when polyols were applied into aqueous solution of boric acid, suggesting that the boric acid forms complexing compounds by combining with polyols.

  2. Photodegradation of α-naphthaleneacetic acid in aqueous solution

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Kinetic processes of α-naphthaleneacetic acid (NAA) photolysis were studied under different conditions. The results showed that the ultraviolet light was more effective than fluorescent light in promoting degradation, and the degradation of NAA under ultraviolet light followed the first order kinetics with the photolysis rate constant of 1.15 x 10-2 min-1 and half-life time (t1/2) of 60 min. Further, it was proved that the photolysis rate was higher in the presence of oxygen, titanium dioxide (TiO2), and low pH ( acidic solution). At last, two photolysis intermediates were identified by GC-MS and possible photolysis pathways were proposed.

  3. Synthesis of high molecular weight polylactic acid from aqueous lactic acid co-catalyzed by tin(II)chloride dihydrate and succinic anhydride

    Institute of Scientific and Technical Information of China (English)

    LEI Ziqiang; BAI Yanbin; WANG Shoufeng

    2005-01-01

    Polylactic acid was synthesized from commercial available cheap aqueous lactic acid (85%―90% w/w) using succinic anhydride and SnCl2·2H2O as catalyst in the absence of organic solvents. As a result, polylactic acid with a molecular weight of 60000 was prepared in 10 h. The new procedure is much simple, cheap and outstanding in that the start material is aqueous lactic acid; the catalytic system is environmentally benign.

  4. Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid and methylglyoxal

    Directory of Open Access Journals (Sweden)

    Y. Tan

    2012-01-01

    Full Text Available Previous experiments have demonstrated that the aqueous OH radical oxidation of methylglyoxal produces low volatility products including pyruvate, oxalate and oligomers. These products are found predominantly in the particle phase in the atmosphere, suggesting that methylglyoxal is a precursor of secondary organic aerosol (SOA. Acetic acid plays a central role in the aqueous oxidation of methylglyoxal and it is a ubiquitous product of gas phase photochemistry, making it a potential "aqueous" SOA precursor in its own right. However, the fate of acetic acid upon aqueous-phase oxidation is not well understood. In this research, acetic acid (20 μM–10 mM was oxidized by OH radicals, and pyruvic acid and methylglyoxal experimental samples were analyzed using new analytical methods, in order to better understand the formation of SOA from acetic acid and methylglyoxal. Glyoxylic, glycolic, and oxalic acids formed from acetic acid and OH radicals. In contrast to the aqueous OH radical oxidation of methylglyoxal, the aqueous OH radical oxidation of acetic acid did not produce succinic acid and oligomers. This suggests that the methylgloxal-derived oligomers do not form through the acid catalyzed esterification pathway proposed previously. Using results from these experiments, radical mechanisms responsible for oligomer formation from methylglyoxal oxidation in clouds and wet aerosols are proposed. The importance of acetic acid/acetate as an SOA precursor is also discussed. We hypothesize that this and similar chemistry is central to the daytime formation of oligomers in wet aerosols.

  5. Radiolytical oxidation of ascorbic acid in aqueous solutions

    International Nuclear Information System (INIS)

    Complete text of publication follows. Ascorbic acid, AsA (vitamin c), has been widely studied as an antioxidant or as an initiator of some technological processes, for example polymerization or nanoparticles formation. AsA can be easily oxidized to ascorbyl radical, in the first stage, and to dehydroascorbic acid, DHA, in the second stage. It has been found that several different ascorbyl radicals are formed during AsA oxidation but the main radical exists as the anion with the unpaired electron delocalized on a highly conjugated tricarbonyl system. Absorption spectrum of ascorbyl radical shows two bands with maxima at 300 and 360 nm, however only that at 360 nm is proportional to the dose and thus this wavelength was chosen for observations. We studied the oxidation of AsA by the following oxidizing radicals generated by the pulse radiolysis method ·OH, (SCN)2-·, Cl2-·, N3· and NO2·. The observed dependence of the yield and the formation rate of the AsA radical on the reduction potential of the oxidizing radical is discussed. The results obtained in water are compared with those obtained with AsA enclosed in the water pools of reverse micelles formed by AOT in n-heptane or by Igepal CO-520 in c-hexane. Somewhat surprising observation of different ascorbyl radical in pulse irradiated reverse micelles containing DHA is also commented.

  6. Entrained solvent separation by charcoal adsorption from aqueous streams generated during uranium recovery from phosphoric acid

    International Nuclear Information System (INIS)

    During the two cycle solvent extraction process for the separation of uranium from phosphoric acid, solvents such as D2EHPA, di nonyl phenyl phosphoric acid (DNPPA), tri butyl phosphate (TBP), etc., get dissolved/entrained in the various aqueous phases such as WPA, ammonium carbonate solution, MGA and sulphuric acid. These solvents have to be separated both from process economy point of view and for industrial acceptability. Systematic experiments showed that recovery of solvents by diluent washing is not effective for alkaline solution. Hence studies were undertaken to study the feasibility of activated charcoal adsorption for entrained/dissolved solvent separation. (author)

  7. Spectrophotometric determination of uranium with benzohydroxamic acid in aqueous medium

    International Nuclear Information System (INIS)

    A spectrophotometric method has been developed for the determination of uranium with benzohydroxamic acid (BHA). Uranium in the hexavalent state forms a yellowish orange colored chelate with BHA. The absorbance of the complex is maximum at pH 6.0, excluding pH7 and complex is stable for more than 72 hours. The maximum absorbance at 304 nm is considered for quantification of uranium. The present method is validated and good agreement with spectrophotometric determination of uranium with thiocyanate. Uranium in the range 1-10 μg/ml has been determined with good precision. The described method is simple, precised and accurate. It can be applied for the determination of uranium in raffinates of Purex process, without producing the nuclear waste in organic phase

  8. Extraction and characterisation of aqueous organic acids from natural waters

    International Nuclear Information System (INIS)

    Humic and fulvic acids were extracted from large volumes of groundwater associated with the Broubster and Needle's Eye natural analogue sites, and the BGS research site at Drigg in Cumbria. Extractions were performed by both batchwise extraction and radial flow chromatography using DEAE-cellulose. Retained humic substances were eluted using NaOH and separated into humic and fulvic components by acidification to pH 1. After separation the humic component was purified by repetitive precipitation and dissolution whilst the fulvic component was purified by absorption chromatography. The resulting humic substances were shown to be of high purity with respect to metallic elements, with less than 1% of available sites being occupied. During elution the association of trace elements with humic substances was monitored and a high degree of association between humic substances, U and the Rare Earth Elements was noted. (author)

  9. Gamma-irradiation of malic acid in aqueous solutions. [prebiotic significance

    Science.gov (United States)

    Negron-Mendoza, A.; Graff, R. L.; Ponnamperuma, C.

    1980-01-01

    The gamma-irradiation of malic acid in aqueous solutions was studied under initially oxygenated and oxygen-free conditions in an attempt to determine the possible interconversion of malic acid into other carboxylic acids, specifically those associated with Krebs cycle. The effect of dose on product formation of the system was investigated. Gas-liquid chromatography combined with mass spectrometry was used as the principal means of identification of the nonvolatile products. Thin layer chromatography and direct probe mass spectroscopy were also employed. The findings show that a variety of carboxylic acids are formed, with malonic and succinic acids in greatest abundance. These products have all been identified as being formed in the gamma-irradiation of acetic acid, suggesting a common intermediary. Since these molecules fit into a metabolic cycle, it is strongly suggestive that prebiotic pathways provided the basis for biological systems.

  10. Scientific Opinion on application EFSA-GMO-NL-2007-45 for the placing on the market of herbicide-tolerant, high-oleic acid, genetically modified soybean 305423 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 from Pioneer

    OpenAIRE

    EFSA Panel on Genetically Modified Organisms (GMO)

    2013-01-01

    Soybean 305423 was developed through particle bombardment and contains gm-fad2-1 and gm-hra expression cassettes, conferring a high oleic acid profile and tolerance to acetolactate synthase (ALS)-inhibiting herbicides. Bioinformatic analyses and genetic stability studies did not raise safety issues. Levels of the GM-HRA protein in soybean 305423 have been sufficiently analysed. Soybean 305423 differs from the conventional counterpart in the seed fatty acid profile and for the presence of the ...

  11. Electrochemical examination of the ascorbic acid radical anion in non-aqueous electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, M.; Honda, K.; Kondo, T.; Rao, T.N.; Tryk, D.A.; Fujishima, A

    2002-10-15

    A quasi-reversible redox reaction involving ascorbic acid was observed in non-aqueous electrolytes at conductive diamond electrode. The chemical reversibility of these reactions is consistent with ascorbic acid being reduced to the ascorbic acid radical anion in a one-electron process, with subsequent reoxidation to ascorbic acid. This is the first report on the electrochemical production of the ascorbic acid radical anion in non-aqueous electrolytes. Ascorbyl 6-stearate and 4-hydroxy 2(5H)-furanone, which have somewhat similar structures as ascorbic acid, also showed one-electron transfer reduction reaction producing radicals with a single negative charge, suggesting that these compounds follow the same electrochemical behavior as ascorbic acid. The double bond and hydroxyl substituent on the five-membered ring are shown to be necessary for the stabilization of the radical anions. It was confirmed by the calculation of the total energy using molecular orbital methods that resonance structures involving the double-bond and hydroxyl group provide significant stabilization of the radical anions. Electrochemical preparation may be a useful method for the detailed study of radicals, their molecular structure and reactivity.

  12. Electrochemical examination of the ascorbic acid radical anion in non-aqueous electrolytes

    International Nuclear Information System (INIS)

    A quasi-reversible redox reaction involving ascorbic acid was observed in non-aqueous electrolytes at conductive diamond electrode. The chemical reversibility of these reactions is consistent with ascorbic acid being reduced to the ascorbic acid radical anion in a one-electron process, with subsequent reoxidation to ascorbic acid. This is the first report on the electrochemical production of the ascorbic acid radical anion in non-aqueous electrolytes. Ascorbyl 6-stearate and 4-hydroxy 2(5H)-furanone, which have somewhat similar structures as ascorbic acid, also showed one-electron transfer reduction reaction producing radicals with a single negative charge, suggesting that these compounds follow the same electrochemical behavior as ascorbic acid. The double bond and hydroxyl substituent on the five-membered ring are shown to be necessary for the stabilization of the radical anions. It was confirmed by the calculation of the total energy using molecular orbital methods that resonance structures involving the double-bond and hydroxyl group provide significant stabilization of the radical anions. Electrochemical preparation may be a useful method for the detailed study of radicals, their molecular structure and reactivity

  13. [Catalytic ozonation by ceramic honeycomb for the degradation of oxalic acid in aqueous solution].

    Science.gov (United States)

    Zhao, Lei; Sun, Zhi-Zhong; Ma, Jun

    2007-11-01

    Comparative experiments for the degradation of oxalic acid in aqueous solution were carried out in the three processes of ozonation alone, ceramic honeycomb-catalyzed ozonation and ceramic honeycomb adsorption. The results show that the degradation rates of oxalic acid in the ceramic honeycomb-catalyzed ozonation, ozonation alone and ceramic honeycomb adsorption systems are 37.6%, 2.2% and 0.4%, and the presence of ceramic honeycomb catalyst significantly improves the degradation rate of oxalic acid compared to the results from non-catalytic ozonation and adsorption. With the addition of tert-butanol, the degradation rates of oxalic acid in catalytic ozonation system decrease by 24.1%, 29.0% and 30.1%, respectively, at the concentration of 5, 10 and 15 mg x L(-1). This phenomenon indicates that ceramic honeycomb-catalyzed ozonation for the degradation of oxalic acid in aqueous solution follows the mechanism of *OH oxidation, namely the heterogeneous surface of catalyst enhances the initiation of *OH. The results of TOC analysis demonstrate that the process of ceramic honeycomb-catalyzed ozonation can achieve the complete mineralization level without the formation of intermediary degradation products. The experimental results suggest that the reaction temperature has positive relationship with the degradation rate of oxalic acid. The degradation rates of oxalic acid in the ceramic honeycomb-catalyzed ozonation system are 16.4%, 37.6%, 61.3% and 68.2%, at the respective reaction temperature of 10, 20, 30 and 40 degrees C.

  14. Electrochemiluminescence of Tris(2,2'-bipyridyl)ruthenium(II) with Ascorbic Acid and Dehydroascorbic Acid in Aqueous and Non-aqueous Solutions.

    Science.gov (United States)

    Takahashi, Fumiki; Hattori, Kaoru; Matsuoka, Masanori; Jin, Jiye

    2016-01-01

    The electrochemiluminescence (ECL) of tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)3(2+)) is studied in non-aqueous media using dehydroascorbic acid (DHA) as coreactant to validate the evidence for the mechanism of the ascorbic acid (H2A)/Ru(bpy)3(2+) ECL system in an aqueous media. DHA is electrochemically reduced around -1.2 V vs. Ag/Ag(+) in pure acetonitrile to generate the ascorbyl radical anion (A(•-)), which is confirmed by in-situ UV-visible absorption measurements using a thin-layer spectroelectrochemical cell. The ECL of the DHA/Ru(bpy)3(2+) system in non-aqueous media is not observed in the potential range from 0 to +1.4 V in anodic potential sweep mode; however, distinct ECL is detected using double potential step electrolysis from -1.2 to +1.4 V vs. Ag/Ag(+). The ECL may be generated by a homogeneous charge-transfer process between A(•-) produced during the first pulse potential step (-1.2 V) and Ru(bpy)3(3+) generated during the second pulse potential step (+1.4 V). The calculated standard enthalpy (-ΔH°) for the charge-transfer reaction between A(•-) and Ru(bpy)3(3+) is 2.29 eV, which is larger than the lowest excited singlet state energy of Ru(bpy)3(2+) (*Ru(bpy)3(2+); 2.03 eV, 610 nm). It is determined that the generated intermediate A(•-) is crucial in the Ru(bpy)3(2+) ECL reaction. PMID:27063718

  15. Synthesis and physical properties of new coco-oleic dimer and trimer plus estolide branched esters

    Science.gov (United States)

    Estolides are a class of esters based on vegetable oils that are formed when the carboxylic acid functionality of one fatty acid reacts at the site of unsaturation of another fatty acid to form an ester linkage. The objective of this preliminary study was to separate coco-oleic estolide into two com...

  16. Highly-acidic aqueous solution as a medium for radiation chemical studies: redox chemistry of phenol

    International Nuclear Information System (INIS)

    Although the aqueous medium is a common choice for radiation induced generation of a variety of transients (radicals), typically a non-aqueous solvent (or even a frozen matrix) is employed to study a transient with a labile H+ (TrH.+), mainly to maintain low propensity of its deprotonation reaction TrH.+→Tr. + H+, that otherwise occur promptly in an aqueous type medium. However, in addition to the relative difficulty encountered in routine handling of such specific non-aqueous reaction media, low transient yield (GTrH.+) therein also restrict their use. Furthermore, any comparative study of the two species TrH.+ and Tr. remains unattainable. In this context we have probed the highly acidic aqueous solution as an alternative medium for radiation induced generation and subsequent chemical studies of acidic radical cation, TrH.+ vis-a-vis the de-protonated radical Tr.. This presentation highlights these results in three parts deals with (a) measurement of oxidizing and reducing radical yields for reactions in H2SO4 and HClO4 solutions, with highest acidity maintained at ∼14 M or Hammett acidity constant H0 - 7 in case of former and ∼10 M or H0 -5.2 in case of the latter; (b) measurement of the H-atom (the sole reducing radical) scavenging efficiency of dissolved O2 in such solution for maintaining exclusive oxidizing condition; and (c) employing these results, oxidation of phenol (C6H5OH) in such medium was probed and the reactions of its radical cation C6H5OH.+ against the phenoxyl radical C6H5O. were compared. Consequently, these studies also revealed an error in the previous measurement of the C6H5OH.+ pKa value (-2.0) which was corrected to -2.75. Details of these studies will be presented to show the efficacy of highly-acidic aqueous solutions as a regular medium for radiation chemical studies. (authors)

  17. Crystallization and immersion freezing ability of oxalic and succinic acid in multicomponent aqueous organic aerosol particles

    Science.gov (United States)

    Wagner, Robert; Höhler, Kristina; Möhler, Ottmar; Saathoff, Harald; Schnaiter, Martin

    2015-04-01

    This study reports on heterogeneous ice nucleation efficiency of immersed oxalic and succinic acid crystals in the temperature range from 245 to 215 K, as investigated with expansion cooling experiments using suspended particles. In contrast to previous laboratory work with emulsified solution droplets where the precipitation of solid inclusions required a preceding freezing/evaporation cycle, we show that immersed solids readily form by homogeneous crystallization within aqueous solution droplets of multicomponent organic mixtures, which have noneutonic compositions with an excess of oxalic or succinic acid. Whereas succinic acid crystals did not act as heterogeneous ice nuclei, immersion freezing by oxalic acid dihydrate crystals led to a reduction of the ice saturation ratio at freezing onset by 0.066-0.072 compared to homogeneous freezing, which is by a factor of 2 higher than previously reported laboratory data. These observations emphasize the importance of oxalic acid in heterogeneous ice nucleation.

  18. Acidity and hydrogen exchange dynamics of iron(II)-bound nitroxyl in aqueous solution.

    Science.gov (United States)

    Gao, Yin; Toubaei, Abouzar; Kong, Xianqi; Wu, Gang

    2014-10-20

    Nitroxyl-iron(II) (HNO-Fe(II)) complexes are often unstable in aqueous solution, thus making them very difficult to study. Consequently, many fundamental chemical properties of Fe(II)-bound HNO have remained unknown. Using a comprehensive multinuclear ((1)H, (15)N, (17)O) NMR approach, the acidity of the Fe(II)-bound HNO in [Fe(CN)5(HNO)](3-) was investigated and its pK(a) value was determined to be greater than 11. Additionally, HNO undergoes rapid hydrogen exchange with water in aqueous solution and this exchange process is catalyzed by both acid and base. The hydrogen exchange dynamics for the Fe(II)-bound HNO have been characterized and the obtained benchmark values, when combined with the literature data on proteins, reveal that the rate of hydrogen exchange for the Fe(II)-bound HNO in the interior of globin proteins is reduced by a factor of 10(6). PMID:25205463

  19. Adsorption of and acidic dye from aqueous solution by surfactant modified bentonite

    International Nuclear Information System (INIS)

    The aim of this paper is to study the adsorption of an acidic dye S. Y. 4 GL (i.e: Supranol yellow 4GL) from aqueous solution on inorgano-organo clay. Bentonite is a kind of natural clay with good exchanging ability. By exchanging its inter lamellar cations with Cetyltrimethylammonium bromide (CTAB) and hydroxy aluminic or chromium poly cations, the properties of natural bentonite can be greatly improved. (Author)

  20. Degradation of acid red 14 by silver ion-catalyzed peroxydisulfate oxidation in an aqueous solution

    OpenAIRE

    RASOULIFARD, Mohammad Hossein; MOHAMMADI, Seied Mohammad Mahdi DOUST

    2012-01-01

    Silver ion (Ag1+)-catalyzed peroxydisulfate was studied for the degradation of acid red 14 (AR-14) in an aqueous medium. The effect of different parameters, such as temperature, peroxydisulfate concentration, and dye and Ag1+ concentrations, were investigated. Application of Ag1+-catalyzed peroxydisulfate, as an advanced oxidation process, introduces an effectual method for wastewater treatment. An accelerated reaction using S2O82- to destroy dyes can be achieved via chemical activat...

  1. The stability of the acetic acid dimer in microhydrated environments and in aqueous solution.

    Science.gov (United States)

    Pašalić, Hasan; Tunega, Daniel; Aquino, Adélia J A; Haberhauer, Georg; Gerzabek, Martin H; Lischka, Hans

    2012-03-28

    The thermodynamic stability of the acetic acid dimer conformers in microhydrated environments and in aqueous solution was studied by means of molecular dynamics simulations using the density functional based tight binding (DFTB) method. To confirm the reliability of this method for the system studied, density functional theory (DFT) and second order Møller-Plesset perturbation theory (MP2) calculations were performed for comparison. Classical optimized potentials for liquid simulations (OPLS) force field dynamics was used as well. One focus of this work was laid on the study of the capabilities of water molecules to break the hydrogen bonds of the acetic acid dimer. The barrier for insertion of one water molecule into the most stable cyclic dimer is found to lie between 3.25 and 4.8 kcal mol(-1) for the quantum mechanical methods, but only at 1.2 kcal mol(-1) for OPLS. Starting from different acetic acid dimer structures optimized in gas phase, DFTB dynamics simulations give a different picture of the stability in the microhydrated environment (4 to 12 water molecules) as compared to aqueous solution. In the former case all conformers are converted to the hydrated cyclic dimer, which remains stable over the entire simulation time of 1 ns. These results demonstrate that the considered microhydrated environment is not sufficient to dissociate the acetic acid dimer. In aqueous solution, however, the DFTB dynamics shows dissociation of all dimer structures (or processes leading thereto) starting after about 50 ps, demonstrating the capability of the water environment to break up the relatively strong hydrogen bridges. The OPLS dynamics in the aqueous environment shows--in contrast to the DFTB results--immediate dissociation, but a similar long-term behavior.

  2. Acceleration of suspending single-walled carbon nanotubes in BSA aqueous solution induced by amino acid molecules.

    Science.gov (United States)

    Kato, Haruhisa; Nakamura, Ayako; Horie, Masanori

    2015-01-01

    Single-walled carbon nanotube (SWCNT) suspensions in aqueous media were prepared using bovine serum albumin (BSA) and amino acid molecules. It was found that the amino acid molecules clearly decreased the time required for suspending the SWCNTs in BSA aqueous solutions. Dynamic light scattering measurements revealed that the particle sizes of the SWCNTs suspended in aqueous media with and without amino acid molecules were approximately the same and stable for more than one week. The zeta potential values of the BSA molecules in pure water and amino acid aqueous solutions were different, and these values were also reflected in the surface potential of colloidal SWCNT particles in the corresponding aqueous media, thus inducing different dispersibility of SWCNTs in aqueous media. Pulsed field gradient nuclear magnetic resonance measurements showed that the interactions between the SWCNTs and the amino acid molecules are weak and comprise chemical exchange interactions and not bonding interactions. Amino acid molecules play a fascinating role in the preparation of SWCNT suspensions in BSA aqueous media by increasing electrostatic repulsive interactions between SWCNT colloidal particles and consequently enhancing the dispersion ability of the BSA molecules.

  3. Insights Into the Aqueous History of Mars from Acid-Sulfate Weathered Phyllosilicates

    Science.gov (United States)

    Craig, P. I.; Ming, D. W.; Rampe, E. B.; Morris, R. V.

    2016-01-01

    Phyllosilicates on Mars are thought to have formed during Mars' earliest Noachian geologic era (approx. 4.1-3.7 Ga). Sulfate formation, on the other hand, requires more acidic conditions which are thought to have occurred later during Mars' Hesperian era (approx. 3.7-3.0 Ga). Therefore, regions on Mars where phyllosilicates and sulfates are found in close proximity to each other provide evidence for the aqueous conditions during this global transition. Both phyllosilicates and sulfates form in the presence of water and thus give clues to the aqueous history of Mars and its potential for habitability. Phyllosilicates that formed during the Noachian era would have been weathered by the prevailing acidic conditions that define the Hesperian. Therefore, the purpose of this study is to characterize the alteration products of acid-sulfate weathered phyllosilicates in laboratory experiments, focusing on the Fe/Mg-smectites commonly identified on Mars. We also compare our results to observations of phyllosilicates and sulfates on Mars in regions such as Endeavour Crater and Mawrth Vallis to understand the formation process of sulfates and constrain the aqueous history of these regions.

  4. RECOVERY OF CARBOXYLIC ACIDS FROM AQUEOUS SOLUTIONS BY LIQUID-LIQUID EXTRACTION WITH A TRIISOOCTYLAMINE DILUENT SYSTEM

    Directory of Open Access Journals (Sweden)

    G. Malmary

    2001-12-01

    Full Text Available Tertiary alkylamines in solution with organic diluents are attractive extractants for the recovery of carboxylic acids from dilute aqueous phases. The aim of this study was to investigate the mechanism for extraction of organic acids from water by a long-chain aliphatic tertiary amine. In order to attain this objective, we studied the liquid-liquid equilibria between the triisooctylamine + 1-octanol + n-heptane system as solvent and an aqueous solution of an individual carboxylic acid such as citric, lactic and malic acids. The experiments showed that the partition coefficient for a particular organic acid depends on the kind of solute, notably when the acid concentration in the aqueous phase is low. A mathematical model, where both chemical association and physical distribution are taken into consideration, is proposed. The model suggests that the various complexes obtained between amine and organic acids contribute to the distribution of the solute between the coexisting phases in equilibrium.

  5. Density, viscosity, and N2O solubility of aqueous amino acid salt and amine amino acid salt solutions

    International Nuclear Information System (INIS)

    Highlights: ► Density of amino acid salt and amine amino acid salt. ► Viscosity of amino acid salt and amine amino acid salt. ► Henry’s law constant/N2O solubility of amino acid salt and amine amino acid salt. ► Schumpe model. Correlations for density, viscosity, and N2O solubility. - Abstract: Physicochemical properties of aqueous amino acid salt (AAS), potassium salt of sarcosine (KSAR) and aqueous amine amino acid salt (AAAS), 3-(methylamino)propylamine/sarcosine (SARMAPA) have been studied. Densities of KSAR were measured for sarcosine mole fraction 0.02 to 0.25 for temperature range 298.15 K to 353.15 K, the viscosities were measured for 0.02 to 0.10 mole fraction sarcosine (293.15 K to 343.15 K) while the N2O solubilities were measured from 0.02 to 0.10 mole fraction sarcosine solutions (298.15 K to 363.15 K). Densities of SARMAPA were measured for sarcosine mole fraction 0.02 to 0.23 for temperature range (298.15 K to 353.15 K), viscosities were measured for 0.02 to 0.16 mole fraction sarcosine (293.15 K to 343.15 K) while the N2O solubilities were measured from 0.02 to 0.16 mole fraction sarcosine solutions (298.15 K to 343.15 K). Experimental results were correlated well with empirical correlations and N2O solubility results for KSAR were predicted adequately by a Schumpe model. The solubilities of N2O in AAS and AAAS are significantly lower than values for amines. The solubilities vary as: amine > AAAS > AAS.

  6. Aldehydes, ketones, and carboxylic acids formed radiolytically in aqueous solutions of cyanides and simple nitriles

    International Nuclear Information System (INIS)

    A systematic search for aldehydes, ketones, and carboxylic acids was carried out in aqueous solutions of HCN, NH4CN, CH3CN, and C2H4CN, that had received multikilogray doses of 60Co γ radiation. About 30 radiolytic products were identified, among them a large variety of dicarboxylic and tricarboxylic acids. Some of them might be of significant interest in molecular evolution studies of prebiotic processes. They originate in the free-radical-initiated chemical reactions where the additional oligomerization processes are particularly important. Most of the radiolytic products appear in both cyanides and nitriles and point to the importance of reactions involving the carbon-nitrogen triple bond

  7. Application of Polyaniline Nano Composite for the Adsorption of Acid Dye from Aqueous Solutions

    OpenAIRE

    Baseri, J.Raffiea; P. N. Palanisamy; P. Sivakumar

    2012-01-01

    In this research, Polyaniline coated sawdust (Polyaniline nano composite) was synthesized via direct chemical polymerization and used as an adsorbent for the removal of acid dye (Acid Violet 49) from aqueous solutions. The effect of some important parameters such as pH, initial concentration of dye, contact time and temperature on the removal efficiency was investigated in batch adsorption system. The adsorption capacity of PAC was high (96.84 %) at a pH of 3-4. The experimental data fitted w...

  8. Statistical Thermodynamic Model for Surface Tension of Aqueous Organic Acids with Consideration of Partial Dissociation.

    Science.gov (United States)

    Boyer, Hallie C; Dutcher, Cari S

    2016-06-30

    With statistical mechanics, an isotherm-based surface tension model for single solute aqueous solutions was derived previously (Wexler et al. J. Phys. Chem. Lett. 2013) for the entire concentration range, from infinite dilution to pure liquid solute, as a function of solute activity. In recent work (Boyer et al. J. Phys. Chem. Lett. 2015), empirical model parameters were reduced through physicochemical interpretations of both electrolyte and organic solutes, enabling surface tension predictions for systems where there is little or no data. The prior binary model is extended in the current work for the first time to treat multicomponent systems to predict surface tensions of partially dissociating organic acids (acetic, butyric, citric, formic, glutaric, maleic, malic, malonic, oxalic, propionic, and succinic acids). These organic acids are especially applicable to the study of atmospheric aqueous aerosols, due to their abundance in the atmosphere. In the model developed here, surface tension depends explicitly on activities of both the neutral organic and deprotonated components of the acid. The relative concentrations of the nondissociated and dissociated mole fractions are found using known dissociation constants. Model parameters strongly depend on molecular size, number of functional groups, O:C ratio, and number of carbons. For all organic acids in this study, fully predictive modeling of surface tensions is demonstrated. PMID:27219322

  9. Aqueous Phase Photo-Oxidation of Succinic Acid: Changes in Hygroscopic Properties and Reaction Products

    Science.gov (United States)

    Hudson, P. K.; Ninokawa, A.; Hofstra, J.; de Lijser, P.

    2013-12-01

    Atmospheric aerosol particles have been identified as important factors in understanding climate change. The extent to which aerosols affect climate is determined, in part, by hygroscopic properties which can change as a result of atmospheric processing. Dicarboxylic acids, components of atmospheric aerosol, have a wide range of hygroscopic properties and can undergo oxidation and photolysis reactions in the atmosphere. In this study, the hygroscopic properties of succinic acid aerosol, a non-hygroscopic four carbon dicarboxylic acid, were measured with a humidified tandem differential mobility analyzer (HTDMA) and compared to reaction products resulting from the aqueous phase photo-oxidation reaction of hydrogen peroxide and succinic acid. Reaction products were determined and quantified using gas chromatography-flame ionization detection (GC-FID) and GC-mass spectrometry (GC-MS) as a function of hydrogen peroxide:succinic acid concentration ratio and photolysis time. Although reaction products include larger non-hygroscopic dicarboxylic acids (e.g. adipic acid) and smaller hygroscopic dicarboxylic acids (e.g. malonic and oxalic acids), comparison of hygroscopic growth curves to Zdanovskii-Stokes-Robinson (ZSR) predictions suggests that the hygroscopic properties of many of the product mixtures are largely independent of the hygroscopicity of the individual components. This study provides a framework for future investigations to fully understand and predict the role of chemical reactions in altering atmospheric conditions that affect climate.

  10. The role of genomics and biotechnology in achieving global food security for high-oleic vegetable oil.

    Science.gov (United States)

    Wilson, Richard F

    2012-01-01

    Health related concerns for dietary 'trans-fat' in the U.S. have mediated a significant decline in the use of hydrogenated vegetable oils in edible applications. Oils having a natural abundance of oleic acid provide many functional properties that are derived from partial hydrogenation of polyunsaturated oils. However, the long term agronomic production capacity of existing high-oleic oil crops to replace hydrogenated oil ingredients is not sustainable. Although improvements are expected in processing technology, genetic modification of seed composition offers the most promising tactic to increase the overall supply of high-oleic commodity oils. Genetic enhancement of oleic acid concentration has been demonstrated experimentally in nearly every oilseed. Private companies have launched production of genetically enhanced oleic acid cultivars such as: Nexera™ Omega-9 canola and Omega-9 sunflower oils. The E. I. du Pont de Nemours and Company plans commercial production of Plenish™ high-oleic soybeans in 2012. The Monsanto Co. plans commercial production of Vistive-Gold™ low-saturated high-oleic soybeans possibly as early as 2013. These 'new' high-oleic oilseeds must not only exhibit superior oil quality but also sequentially improved yield potential. Genetic maps that help breeders identify, locate and track useful genes will facilitate accomplishment of that goal. However, a reference sequence map in soybean is the only available chromosome scale assembly of an oilseed genome. Knowledge of genome structure enables technological advances that help increase soybean yielding ability, improve crop protection against biotic stresses, and reveal alleles for genes that mediate expression of quality traits. Led by soybean, genetically enhanced high-oleic vegetable oils that now are becoming commercially available may capture greater than 40% of the domestic consumption of vegetable oil in the U.S. by 2020. This innovation in oilseed technology is a positive step toward

  11. Radiolysis of aqueous solutions of acetic acid in the presence of Na-montmorillonite

    Science.gov (United States)

    Navarro-Gonzalez, R.; Negron-Mendoza, A.; Ramos, S.; Ponnamperuma, C.

    1990-01-01

    The gamma-irradiation of 0.8 mol dm-3 aqueous, oxygen-free acetic acid solutions was investigated in the presence or absence of Na-montmorillonite. H2, CH4, CO, CO2, and several polycarboxylic acids were formed in all systems. The primary characteristics observed in the latter system were: (1) Higher yield of the decomposition of acetic acid; (2) Lower yield of the formation of polycarboxylic acids; (3) No effect on the formation of methane; (4) Higher yield of the formation of carbon dioxide; and (5) The reduction of Fe3+ in the octahedral sites of Na-montmorillonite. A possible reaction scheme was proposed to account for the observed changes. The results are important in understanding heterogeneous processes in radiation catalysis and might be significant to prebiotic chemistry.

  12. Recovery of acetic acid from an aqueous pyrolysis oil phase by reactive extraction using tri-n-octylamine

    NARCIS (Netherlands)

    Rasrendra, C. B.; Girisuta, B.; van de Bovenkamp, H. H.; Winkelman, J. G. M.; Leijenhorst, E. J.; Venderbosch, R. H.; Windt, M.; Meier, D.; Heeres, H. J.

    2011-01-01

    The application of reactive extraction to isolate organic acids, particularly acetic acid, from the aqueous stream of phase splitted pyrolysis oil using a long chain aliphatic tertiary amine is reported. Acetic acid recovery was optimized by selecting the proper amine and diluent combination and adj

  13. Scientific Opinion on application (EFSA-GMO-NL-2010-78) for the placing on the market of herbicide-tolerant, increased oleic acid genetically modified soybean MON 87705 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 from Monsanto

    OpenAIRE

    EFSA Panel on Genetically Modified Organisms (GMO)

    2012-01-01

    This scientific opinion is a risk assessment of the genetically modified, herbicide-tolerant, increased oleic acid soybean MON 87705 for food and feed uses, import and processing. MON 87705 contains the soybean FAD2-1A/FATB1-A gene fragments down-regulating endogenous FAD2 and FATB enzymes and the CP4 epsps gene cassette conferring tolerance to glyphosate-containing herbicides. Bioinformatic analyses and genetic stability studies did not rais...

  14. Stability of clavulanic acid in PEG/citrate and liquid–liquid extraction in aqueous two-phase system

    OpenAIRE

    Carneiro-da-Cunha, M. N.; Souza, K. P. S.; Mota, A; J.A. Teixeira; Porto, C S; Porto, Tatiana Souza; Porto, Ana L. F.

    2014-01-01

    β-Lactamases are enzymes responsible for the hydrolysis of β-lactam antibiotics, being produced by several pathogenic bacteria. Clavulanic acid is a commercially and clinically important β-lactamase inhibitor, its extraction being possible by the application of aqueous two-phase system. In this study, clavulanic acid stability was investigated at different molar mass PEG (400, 1 000 and 20 000 g mol−1) and at different citrate concentrations (5 and 20%) PEG/citrate aqueous-two phase systems (...

  15. Hydrogen bonding of single acetic acid with water molecules in dilute aqueous solutions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In separation processes,hydrogen bonding has a very significant effect on the efficiency of isolation of acetic acid (HOAc) from HOAc/H2O mixtures. This intermolecular interaction on aggregates composed of a single HOAc molecule and varying numbers of H2O molecules has been examined by using ab initio molecular dynamics simulations (AIMD) and quantum chemical calculations (QCC). Thermodynamic data in aqueous solution were obtained through the self-consistent reaction field calculations and the polarizable continuum model. The aggregation free energy of the aggregates in gas phase as well as in aqueous system shows that the 6-membered ring is the most favorable structure in both states. The relative stability of the ring structures inferred from the thermodynamic properties of the QCC is consistent with the ring distributions of the AIMD simulation. The study shows that in dilute aqueous solution of HOAc the more favorable molecular interaction is the hydrogen bonding between HOAc and H2O molecules,resulting in the separation of acetic acid from the HOAc/H2O mixtures with more difficulty than usual.

  16. Adsorption and Desorption Behavior of Tannic Acid in Aqueous Solution on Polyaniline Adsorbent

    Institute of Scientific and Technical Information of China (English)

    WANG Jiahong; JI Yanfen; DING Shaolan; MA Hongrui; HAN Xiaojing

    2013-01-01

    Tannic acid is generally considered as one of polyphenolic pollutants,which may cause severe threats to the environment.In this study,polyaniline adsorbent was synthesized by chemical oxidation to remove tannic acid in aqueous solutions.The adsorption amount of tannic acid varied greatly with pH of solution and strong adsorption was at pH 5.8-6.7.Coexisting cations,such as Na+,K+,and Ca2+,can enhance the adsorption of tannic acid on polyaniline,which may be contributed to the electrostatic interaction between tannic acid and polyaniline.The adsorption process could be well described by Langmuir model and the maximum adsorption capacity was 117.65 mg·g-1 at 35 ℃ and pH 6.0.The thermodynamic parameters calculated from the adsorption isotherms indicate that the adsorption of tannic acid is spontaneous and endothermic process.The polyaniline saturated with tannic acid can be desorbed in alkaline solution and regenerated adsorbent can be used repeatedly with high adsorption capacity,which implies that polyaniline adsorbents have a great potential in water purification for the removal of tannic acid.

  17. Interaction of Atmospheric-Pressure Air Microplasmas with Amino Acids as Fundamental Processes in Aqueous Solution.

    Directory of Open Access Journals (Sweden)

    Renwu Zhou

    Full Text Available Plasma medicine is a relatively new field that investigates potential applications of cold atmospheric-pressure plasmas in bioengineering, such as for bacterial inactivation and degradation of organic molecules in water. In order to enunciate mechanisms of bacterial inactivation at molecular or atomic levels, we investigated the interaction of atmospheric-pressure air microplasmas with amino acids in aqueous solution by using high-resolution mass spectrometry (HRMS. Results show that the oxidation effect of plasma-induced species on the side chains of the amino acids can be categorized into four types, namely hydroxylation, nitration, dehydrogenation and dimerization. In addition, relative activities of amino acids resulting from plasma treatment come in descending order as follows: sulfur-containing carbon-chain amino acids > aromatic amino acids > five-membered ring amino acids > basic carbon-chain amino acids. Since amino acids are building blocks of proteins vital to the growth and reproduction of bacteria, these results provide an insight into the mechanism of bacterial inactivation by plasma.

  18. Separation of Acetic Acid from Aqueous Solution using Various Organic Solvents

    Directory of Open Access Journals (Sweden)

    Md. Zaved Hossain Khan

    2014-01-01

    Full Text Available 800x600 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 In the study a model has been developed to separate the acetic acid from aqueous solution by liquid-liquid extraction and find out the proper solvent for this separation. Various solvents such as n-butanol, iso butanol, amyl alcohol and ethyl acetate are used for separation of acetic acid from water. The binodal curves (mutual solubility curves for acetic acid distributed between water and an organic solvent were obtained by titrating known mixtures of two components (water and solvents with the third component acetic acid to the point of first appearance of permanent turbidity. In order to determine the tie-lines, the absorbance of the coexisting phases, obtained by the separation of ternary mixtures within the binodal curve are needed to be determined. The absorbance of each point had been determined by a UV spectrophotometer. Distribution diagrams are obtained by plotting weight percent of acetic acid in solvent phase against the weight percent of acetic acid in water phase. Selectivity diagrams are also obtained by plotting (wt. % of acetic acid / (percent of acetic acid + percent of water in solvent phase against the same quantity in the diluent phase. The separation factor is determined numerically from the tie-line data.

  19. Modeling of density of aqueous solutions of amino acids with the statistical associating fluid theory

    Energy Technology Data Exchange (ETDEWEB)

    Ji Peijun [College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Feng Wei [College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)]. E-mail: fengwei@mail.buct.edu.cn; Tan Tianwei [College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)

    2007-07-15

    The density of aqueous solutions of amino acids has been modeled with the statistical associating fluid theory (SAFT) equation of state. The modeling is accomplished by extending the previously developed new method to determine the SAFT parameters for amino acids. The modeled systems include {alpha}-alanine/H{sub 2}O, {beta}-alanine/H{sub 2}O, proline/H{sub 2}O, L-asparagine/H{sub 2}O, L-glutamine/H{sub 2}O, L-histidine/H{sub 2}O, serine/H{sub 2}O, glycine/H{sub 2}O, alanine/H{sub 2}O/sucrose, DL-valine/H{sub 2}O/sucrose, arginine/H{sub 2}O/sucrose, serine/H{sub 2}O/ethylene glycol, and glycine/H{sub 2}O/ethylene glycol. The density of binary solutions of amino acids has been correlated or predicted with a high precision. And then the density of multicomponent aqueous solutions of amino acids has been modeled based on the modeling results of binary systems, and a high accuracy of density calculations has been obtained. Finally, the water activities of DL-valine/H{sub 2}O, glycine/H{sub 2}O, and proline/H{sub 2}O have been predicted without using binary interaction parameters, and good results have been obtained.

  20. Determination of hydroxyl radicals with salicylic acid in aqueous nitrate and nitrite solutions

    Institute of Scientific and Technical Information of China (English)

    YANG Xi; ZHAN Man-jun; KONG Ling-ren; WANG Lian-sheng

    2004-01-01

    The qualitative and quantitative analyses of reactive oxygen species are essential to determine their steady-state concentration and related reaction mechanisms in environmental aquatic systems. In this study, salicylic acid was employed as an innovative molecular probe of hydroxyl radical(OH) generated in aqueous nitrate and nitrite solutions through photochemical reactions. Kinetic studies showed that the steady-state concentrations of OH in aqueous NO3-(10 mmol/L, pH = 5) and NO2- (10 mmol/L, pH = 5) solutions under ultraviolet irradiation were at a same magnitude, 10-15 mol/L. Apparent quantum yields of OH at 313 nm were measured as 0.011 and 0.07 for NO3- and NO2- respectively, all comparable to the results of previous studies.

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

    Science.gov (United States)

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

    2012-01-01

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

  2. ADSORPTION OF TANNIN ACID ONTO AN AMINATED MACROPOROUS RESIN FROM AQUEOUS SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A macroporous polymeric adsorbent NG-8 was synthesized with divinylbenzene using conventional suspension polymerization technique. Its aminated product NG-9 was prepared by introducing tertiary amino groups into NG-8 for removal of tannin acid from aqueous solutions. NG-9 could be used directly without a wetting process and had higher adsorption capacity than NG-8, which might be attributed to the enhanced adsorbent-adsorbate interaction due to the tertiary amino groups on the polymeric matrix. The Langmuir equation was successfully employed to describe the adsorption process. The adsorption enthalpy change further validated the uptake of tannin acid on NG-9 to be an enhanced physical adsorption because of the Lewis acid-base interaction. In addition, adsorption kinetic studies testified that the tertiary amino groups on the polymer matrix could decrease the adsorption rate maybe for the hindrance of the tertiary amino groups and water clusters built up.

  3. Aqueous extracts of Mozambican plants as alternative and environmentally safe acid-base indicators.

    Science.gov (United States)

    Macuvele, Domingos Lusitaneo Pier; Sithole, Gerre Zebedias Samo; Cesca, Karina; Macuvele, Suzana Lília Pinare; Matsinhe, Jonas Valente

    2016-06-01

    Indicators are substances that change color as the pH of the medium. Many of these substances are dyes of synthetic origin. The mulala plant (Euclea natalensis), which roots are commonly used by rural communities for their oral hygiene, and roseira (Hibiscus rosa-sinensis), an ornamental plant, are abundant in Mozambique. Currently, synthetic acid-base indicators are most commonly used but have environmental implications and, on the other hand, are expensive products, so the demand for natural indicators started. This study investigated the applicability of aqueous extracts of H. rosa-sinensis and E. natalensis as acid-base indicators. Ground on this work, the extracts can be used as acid-base indicators. On the basis of the absorption spectroscopy in both the UV-Vis region and previous studies, it was possible to preliminarily pinpoint anthocyanins and naphthoquinones as responsible for the shifting of colors depending on the pH range of aqueous extracts of H. rosa-sinensis and E. natalensis. These natural indicators are easily accessible, inexpensive, easy to extract, environmentally safe, and locally available. PMID:26936478

  4. Inhibition of gastric acid secretion by the aqueous extract and purified extracts of Stachytarpheta cayennensis.

    Science.gov (United States)

    Vela, S M; Souccar, C; Lima-Landman, M T; Lapa, A J

    1997-02-01

    Stachytarpheta cayennensis Schauer (Verbenaceae) is used in folk medicine to treat gastric and intestinal disturbances. The freeze-dried aqueous extract of the whole plant tested to rodents up to the dose of 2 g kg-1, p.o., did not produce signs of toxicity. The extract (0.5-2 g kg-1, p.o.) increased the intestinal motility and protected mice against ulcers induced by restraintin-cold, ethanol or indomethacin. Injected into the duodenal lumen the extract inhibited the basal acid secretion as well as that induced by histamine and bethanecol in pylorus-ligated mice. Partition of the aqueous extract in organic solvents yielded semipurified fractions whose antiacid activity guided further chemical purification. All the fractions were chromatographically characterized, the main substances in the active extract being flavonoids and amines; some substances were revealed only under UV light. The most purified active fraction obtained presented a specific activity 5-10 times higher than that detected in the original extract. Data from pharmacological studies indicate that the antiulcer activity of S. cayennensis is related to a specific inhibition of gastric acid secretion. Cholinergic and histaminergic stimulation of acid secretion were similarly reduced by the extracts suggesting inhibition of common steps in both pathways, possibly at the level of histamine release/H2 receptor interaction, or at the proton pump. Whatever the mechanisms involved, the present data confirm the plant effectiveness as antiacid/antiulcer and laxative. PMID:9063095

  5. The effect of electron irradiation on aqueous dispersions of humic acids and lignin

    International Nuclear Information System (INIS)

    The effect of irradiation by accelerated electrons on optical absorption of diluted aqueous solutions of lignin and humic acids was studied under two different irradiation conditions: when thickness of irradiated solution layer was less than the electrons range in the solution (mode I) and vice versa (mode II). Dominating agglomeration and sedimentation of the compounds has been demonstrated to take place under irradiation in mode I, maximal effect being achieved at absorbed dose 5–15 kGy. Under irradiation in mode II, i.e. when all the incident electrons were being absorbed, the radiation-induced coagulation was depressed. The dependence of radiation effect on irradiation conditions may be caused by stabilizing action of accumulating excess charge of absorbed electrons on negatively charged micelles of lignin and humic acids. - Highlights: • Electron irradiation promotes coagulation in aqueous dispersions of lignin and humic acids. • Maximal effect of coagulation is achieved at absorbed dose 5–15 kGy. • Negative charge accumulating by absorption of incident electrons results in stabilizing negatively charged micelles

  6. An Exact Method to Determine the Conductivity of Aqueous Solutions in Acid-Base Titrations

    Directory of Open Access Journals (Sweden)

    Norma Rodríguez-Laguna

    2015-01-01

    Full Text Available Several works in the literature show that it is possible to establish the analytic equations to estimate the volume V of a strong base or a strong acid (Vb and Va, resp. being added to a solution of a substance or a mix of substances during an acid-base titration, as well as the equations to estimate the first derivative of the titration plot dpH/dV, and algebraic expressions to determine the buffer β capacity with dilution βdil. This treatment allows establishing the conditions of thermodynamic equilibria for all species within a system containing a mix of species from one or from various polyacid systems. The present work shows that it is possible to determine exactly the electric conductivity of aqueous solutions for these Brønsted acid-base titrations, because the functional relation between this property and the composition of the system in equilibrium is well known; this is achieved using the equivalent conductivity λi values of each of the ions present in a given system. The model employed for the present work confirms the experimental outcomes with the H2SO4, B(OH3, CH3COOH, and H3PO4 aqueous solutions’ titration.

  7. Heterogeneous catalysis contribution for the denitration of aqueous nuclear radioactive waste with formic acid

    International Nuclear Information System (INIS)

    The chemical denitration aims to reduce the nitric acid concentration in nuclear fuel reprocessing aqueous wastes by adding formic acid as a reducing agent. The denitration reaction exhibits an induction period, which duration is related to the time needed by the key intermediate of the reaction, i.e. nitrous acid, to reach a threshold concentration in the reaction medium. The addition of a Pt/SiO2 catalyst in the reaction mixture suppresses the induction period of the chemical denitration. The aim of the present work is to identify the role of Pt/SiO2 in the catalytic denitration mechanism. The experimental work is based on the comparison of catalytic tests performed with various catalysts, in order to identify the intrinsic characteristics of Pt/SiO2 that might influence its activity for the reaction. Catalytic denitration results show that Pt/SiO2 acts only by speeding up the nitrous acid generation in the solution until its concentration reaches the threshold level of 0,01 mol L-1 in the experimental conditions. Catalysts activity is evaluated by quantifying the nitrous acid generated on the platinum surface during the induction period of the homogeneous denitration reaction. The large platinum aggregates reactivity is greater than the one of nano-sized particles. The study of the key step of the catalytic denitration reaction, the catalytic generation of nitrous acid, clarifies the role of Pt/SiO2. The homogeneous denitration is initiated thanks to a redox cycle on the catalyst surface: an initial oxidation of Pt0 by nitric acid, which is reduced into nitrous acid, followed by the reduction of the passivated 'Ptox' by formic acid. Furthermore, a platinum reduction by formic acid prior to the catalytic test prevents any platinum leaching from the catalyst into the nitric solution, being all the more significant as platinum dispersion is high. (author)

  8. Temperature effect on adiolysis of deaerated acid aqueous solutions of ferrous sulfate

    International Nuclear Information System (INIS)

    In the course of γ-radiolysis (60Co, dose rate=3.75 Gr/c, doses=1.575-3.375 kGr) of deaerated acid aqueous solution 3.6x10-3 mol/l of ferrous sulfate in the 20-250 deg C range the hydrogen molecules radiochemical yield per 100 eV of absorbed energy G(H2) decreases from 3.82±0.12 to 2.72±0.26, whereas G(Fe3+) independently of temperature is equal 8.34±0.36

  9. Aqueous phototransformation of bisphenol S: the competitive radical-attack pathway to p-hydroxybenzenesulfonic acid.

    Science.gov (United States)

    Wang, Xiaowen; Ma, Jiahai; Wang, Zhenpeng; Guo, Rongrong; Hu, Xuefeng

    2014-01-01

    The kinetics, environmental influencing factors, products and reaction mechanism of aqueous phototransformation of bisphenol S (BPS), as an alternative to bisphenol A, which is of environmental concern, were investigated. p-Hydroxybenzenesulfonic acid, as the major transformation product was confirmed by gas chromatography - mass spectrometry, electrospray ionization, ¹H nuclear magnetic resonance and fluorescence spectrum analysis. A reaction pathway was proposed based on the reactive oxygen species related results by electron paramagnetic resonance and radical traps. The competition of the excited state of BPS between transferring electron to O₂ to •O₂(-) and directly oxidizing H₂O to •OH was revealed.

  10. A Greener, Efficient Approach to Michael Addition of Barbituric Acid to Nitroalkene in Aqueous Diethylamine Medium

    Directory of Open Access Journals (Sweden)

    Hany J. Al-Najjar

    2014-01-01

    Full Text Available An efficient method for the synthesis of a variety of pyrimidine derivatives 3a–t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a–k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The structure of compound 3a was further confirmed by single crystal X-ray structure determination.

  11. Degradation of hydroxycinnamic acid mixtures in aqueous sucrose solutions by the Fenton process.

    Science.gov (United States)

    Nguyen, Danny M T; Zhang, Zhanying; Doherty, William O S

    2015-02-11

    The degradation efficiencies and behaviors of caffeic acid (CaA), p-coumaric acid (pCoA), and ferulic acid (FeA) in aqueous sucrose solutions containing the mixture of these hydroxycinnamic acids (HCAs) were studied by the Fenton oxidation process. Central composite design and multiresponse surface methodology were used to evaluate and optimize the interactive effects of process parameters. Four quadratic polynomial models were developed for the degradation of each individual acid in the mixture and the total HCAs degraded. Sucrose was the most influential parameter that significantly affected the total amount of HCA degraded. Under the conditions studied there was a sucrose in all reactions. The optimal values of the process parameters for a 200 mg/L HCA mixture in water (pH 4.73, 25.15 °C) and sucrose solution (13 mass %, pH 5.39, 35.98 °C) were 77% and 57%, respectively. Regression analysis showed goodness of fit between the experimental results and the predicted values. The degradation behavior of CaA differed from those of pCoA and FeA, where further CaA degradation is observed at increasing sucrose and decreasing solution pH. The differences (established using UV/vis and ATR-FTIR spectroscopy) were because, unlike the other acids, CaA formed a complex with Fe(III) or with Fe(III) hydrogen-bonded to sucrose and coprecipitated with lepidocrocite, an iron oxyhydroxide.

  12. Degradation of hydroxycinnamic acid mixtures in aqueous sucrose solutions by the Fenton process.

    Science.gov (United States)

    Nguyen, Danny M T; Zhang, Zhanying; Doherty, William O S

    2015-02-11

    The degradation efficiencies and behaviors of caffeic acid (CaA), p-coumaric acid (pCoA), and ferulic acid (FeA) in aqueous sucrose solutions containing the mixture of these hydroxycinnamic acids (HCAs) were studied by the Fenton oxidation process. Central composite design and multiresponse surface methodology were used to evaluate and optimize the interactive effects of process parameters. Four quadratic polynomial models were developed for the degradation of each individual acid in the mixture and the total HCAs degraded. Sucrose was the most influential parameter that significantly affected the total amount of HCA degraded. Under the conditions studied there was a analysis showed goodness of fit between the experimental results and the predicted values. The degradation behavior of CaA differed from those of pCoA and FeA, where further CaA degradation is observed at increasing sucrose and decreasing solution pH. The differences (established using UV/vis and ATR-FTIR spectroscopy) were because, unlike the other acids, CaA formed a complex with Fe(III) or with Fe(III) hydrogen-bonded to sucrose and coprecipitated with lepidocrocite, an iron oxyhydroxide. PMID:25585639

  13. Alginic acid and hyaluronic acid, effective stabilizers of carthamin red colour in aqueous solutions

    Directory of Open Access Journals (Sweden)

    Koshi Saito

    2014-02-01

    Full Text Available Sodium salts and free forms of two heterosaccharides, alginic and hyaluronic acids were mixed with carthamin in a buffer at pH 5.5 and their preservation effects of carthamin red colour were screened after incubation for 24 h at 3-5oC in the dark. The effects observed were (alginic acid/hyaluronic acid, % on average: 69.3/60.3, for which the values are higher by 40.9 and 29.1%, respectively, compared with those of the control which was conducted with no addition of heterosaccharides. Alginic acid is a more promising stabilizer than haluronic acid, indicating that active groups such as hydroxyls, carboxyls and amino groups on the building units of the macromolecules are associated closely with the carthamin red colour preservation. The empirical outcomes are referred to the practical application of carthamin as a colourant of food products.

  14. Formation of isomers of anionic hemiesters of sugars and carbonic acid in aqueous medium.

    Science.gov (United States)

    Dos Santos, Vagner B; Vidal, Denis T R; Francisco, Kelliton J M; Ducati, Lucas C; do Lago, Claudimir L

    2016-06-16

    Hemiesters of carbonic acid can be freely formed in aqueous media containing HCO3(-)/CO2 and mono- or poly-hydroxy compounds. Herein, (13)C NMR spectroscopy was used to identify isomers formed in aqueous solutions of glycerol (a prototype compound) and seven carbohydrates, as well as to estimate the equilibrium constant of formation (Keq). Although both isomers are formed, glycerol 1-carbonate corresponds to 90% of the product. While fructose and ribose form an indistinct mixture of isomers, the anomers of d-glucopyranose 6-carbonate correspond to 74% of the eight isomers of glucose carbonate that were detected. The values of Keq for the disaccharides sucrose (4.3) and maltose (4.2) are about twice the values for the monosaccharides glucose (2.0) and fructose (2.3). Ribose (Keq = 0.89)-the only sugar without a significant concentration of a species containing a -CH2OH group in an aqueous solution-resulted in the smallest Keq. On the basis of the Keq value and the concentrations of HCO3(-) and glucose in blood, one can anticipate a concentration of 2-4 µmol L(-1) for glucose 6-carbonate, which corresponds to ca. of 10% of its phosphate counterpart (glucose 6-phosphate).

  15. Leaching of lead from zinc leach residue in acidic calcium chloride aqueous solution

    Science.gov (United States)

    Wang, Le; Mu, Wen-ning; Shen, Hong-tao; Liu, Shao-ming; Zhai, Yu-chun

    2015-05-01

    A process with potentially reduced environmental impacts and occupational hazards of lead-bearing zinc plant residue was studied to achieve a higher recovery of lead via a cost-effective and environmentally friendly process. This paper describes an optimization study on the leaching of lead from zinc leach residue using acidic calcium chloride aqueous solution. Six main process conditions, i.e., the solution pH value, stirring rate, concentration of CaCl2 aqueous solution, liquid-to-solid (L/S) ratio, leaching temperature, and leaching time, were investigated. The microstructure and components of the residue and tailing were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). On the basis of experimental results, the optimum reaction conditions were determined to be a solution pH value of 1, a stirring rate of 500 r·min-1, a CaCl2 aqueous solution concentration of 400 g·L-1, a liquid-to-solid mass ratio of 7:1, a leaching temperature of 80°C, and a leaching time of 45 min. The leaching rate of lead under these conditions reached 93.79%, with an iron dissolution rate of 19.28%. Silica did not take part in the chemical reaction during the leaching process and was accumulated in the residue.

  16. Formation of isomers of anionic hemiesters of sugars and carbonic acid in aqueous medium.

    Science.gov (United States)

    Dos Santos, Vagner B; Vidal, Denis T R; Francisco, Kelliton J M; Ducati, Lucas C; do Lago, Claudimir L

    2016-06-16

    Hemiesters of carbonic acid can be freely formed in aqueous media containing HCO3(-)/CO2 and mono- or poly-hydroxy compounds. Herein, (13)C NMR spectroscopy was used to identify isomers formed in aqueous solutions of glycerol (a prototype compound) and seven carbohydrates, as well as to estimate the equilibrium constant of formation (Keq). Although both isomers are formed, glycerol 1-carbonate corresponds to 90% of the product. While fructose and ribose form an indistinct mixture of isomers, the anomers of d-glucopyranose 6-carbonate correspond to 74% of the eight isomers of glucose carbonate that were detected. The values of Keq for the disaccharides sucrose (4.3) and maltose (4.2) are about twice the values for the monosaccharides glucose (2.0) and fructose (2.3). Ribose (Keq = 0.89)-the only sugar without a significant concentration of a species containing a -CH2OH group in an aqueous solution-resulted in the smallest Keq. On the basis of the Keq value and the concentrations of HCO3(-) and glucose in blood, one can anticipate a concentration of 2-4 µmol L(-1) for glucose 6-carbonate, which corresponds to ca. of 10% of its phosphate counterpart (glucose 6-phosphate). PMID:27111726

  17. Adsorption of uranium ions by crosslinked polyester resin functionalized with acrylic acid from aqueous solutions

    International Nuclear Information System (INIS)

    In this paper, the crosslinked polyester resin containing acrylic acid functional groups was used for the adsorption of uranium ions from aqueous solutions. For this purpose, the crosslinked polyester resin of unsaturated polyester in styrene monomer (Polipol 353, Poliya) and acrylic acid as weight percentage at 80 and 20%, respectively was synthesized by using methyl ethyl ketone peroxide (MEKp, Butanox M60, Azo Nobel)-cobalt octoate initiator system. The adsorption of uranium ions on the sample (0.05 g copolymer and 5 mL of U(VI) solution were mixed) of the crosslinked polyester resin functionalized with acrylic acid was carried out in a batch reactor. The effects of adsorption parameters of the contact time, temperature, pH of solution and initial uranium(VI) concentration for U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid were investigated. The adsorption data obtained from experimental results depending on the initial U(VI) concentration were analyzed by the Freundlich, Langmuir and Dubinin-Radushkevich (D-R) adsorption isotherms. The adsorption capacity and free energy change were determined by using D-R isotherm. The obtained experimental adsorption data depending on temperature were evaluated to calculate the thermodynamic parameters of enthalpy (ΔHo), entropy (ΔSo) and free energy change (ΔGo) for the U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid from aqueous solutions. The obtained adsorption data depending on contact time were analyzed by using adsorption models such as the modified Freundlich, Elovich, pseudo-first order and pseudo-second-order kinetic models. (author)

  18. Laboratory photochemical processing of aqueous aerosols: formation and degradation of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls

    Directory of Open Access Journals (Sweden)

    C. M. Pavuluri

    2015-01-01

    Full Text Available To better understand the photochemical processing of dicarboxylic acids and related polar compounds, we conducted batch UV irradiation experiments on two types of aerosol samples collected from India, which represent anthropogenic (AA and biogenic aerosols (BA, for time periods of 0.5 to 120 h. The irradiated samples were analyzed for molecular compositions of diacids, oxoacids and α-dicarbonyls. The results show that photochemical degradation of oxalic (C2 and malonic (C3 and other C8-C12 diacids overwhelmed their production in aqueous aerosols whereas succinic acid (C4 and C5-C7 diacids showed a significant increase (ca. 10 times during the course of irradiation experiments. The photochemical formation of oxoacids and α-dicarbonyls overwhelmed their degradation during the early stages of experiment, except for ω-oxooctanoic acid (ωC8 that showed a similar pattern to that of C4. We also found a gradual decrease in the relative abundance of C2 to total diacids and an increase in the relative abundance of C4 during prolonged experiment. Based on the changes in concentrations and mass ratios of selected species with the irradiation time, we hypothesize that iron-catalyzed photolysis of C2 and C3 diacids dominates their concentrations in Fe-rich atmospheric waters, whereas photochemical formation of C4 diacid (via ωC8 is enhanced with photochemical processing of aqueous aerosols in the atmosphere. This study demonstrates that the ambient aerosols contain abundant precursors that produce diacids, oxoacids and α-dicarbonyls, although some species such as oxalic acid decompose extensively during an early stage of photochemical processing.

  19. Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part I. Regeneration of Amine-Carboxylic Acid Extracts

    Energy Technology Data Exchange (ETDEWEB)

    Poole, L.J.; King, C.J.

    1990-03-01

    Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with tertiary amines. An approach for regeneration and product recovery from such extracts is to back-extract the carboxylic acid with a water-soluble, volatile tertiary amine, such as trimethylamine. The resulting trimethylammonium carboxylate solution can be concentrated and thermally decomposed, yielding the product acid and the volatile amine for recycle. Experimental work was performed with lactic acid, succinic acid, and fumaric acid. Equilibrium data show near-stoichiometric recovery of the carboxylic acids from an organic solution of Alamine 336 into aqueous solutions of trimethylamine. For fumaric and succinic acids, partial evaporation of the aqueous back extract decomposes the carboxylate and yields the acid product in crystalline form. The decomposition of aqueous solutions of trimethylammonium lactates was not carried out to completion, due to the high water solubility of lactic acid and the tendency of the acid to self-associate. The separate recovery of ammonia and acid gases from sour waters can be achieved by combining steam-stripping of the acid gases with simultaneous removal of ammonia by extraction with a liquid cation exchanger. The use of di-2,4,4-trimethylpentyl phosphinic acid as the liquid cation exchanger is explored in this work. Batch extraction experiments were carried out to measure the equilibrium distribution ratio of ammonia between an aqueous buffer solution and an organic solution of the phosphinic acid (0.2N) in Norpar 12. The concentration

  20. Selenium dioxide catalysed oxidation of acetic acid hydrazide by bromate in aqueous hydrochloric acid medium

    Indian Academy of Sciences (India)

    R S Yalgudre; G S Gokavi

    2012-07-01

    Selenium dioxide catalysed acetic acid hydrazide oxidation by bromate was studied in hydrochloric acid medium. The order in oxidant concentration, substrate and catalyst were found to be unity. Increasing hydrogen ion concentration increases the rate of the reaction due to protonation equilibria of the oxidant. The mechanism of the reaction involves prior complex formation between the catalyst and substrate, hydrazide, followed by its oxidation by diprotonated bromate in a slow step. Acetic acid was found to be the oxidation product. Other kinetic data like effect of solvent polarity and ionic strength on the reaction support the proposed mechanism.

  1. Kinetics and Mechanism of Oxidation of Glutamic Acid by N-Bromophthalimide in Aqueous Acidic Medium

    OpenAIRE

    2011-01-01

    The kinetics of oxidation of glutamic acid (Glu) with N-bromophthalimide (NBP) was studied in perchloric acid medium at 30 °C by potentiometric method. The reaction is first order each in NBP and glutamic acid and is negative fractional order in [H+]. Addition of KBr or the reaction product, phthalimide had no effect on the rate. Similarly variation of ionic strength of the medium did not affect the rate of the reaction. Also the rate increased with decrease in dielectric constant of the reac...

  2. [Changes in the collagen amino acid composition of calf skin after gamma-irradiation in an aqueous solution].

    Science.gov (United States)

    Duzhenkova, N A; Savich, A V

    1983-01-01

    A study was made of the amino acid composition of calf skin collagen after gamma-irradiation (60Co) of 2.5 X 10(-6) M aerated aqueous protein solution within the dose range from 30 to 2000 Gy. The radiosensitivity of amino acid residues was compared. PMID:6657935

  3. Standard enthalpies of formation of γ-aminobutyric acid and the products of its dissociation in aqueous solution

    Science.gov (United States)

    Lytkin, A. I.; Chernikov, V. V.; Krutova, O. N.; Skvortsov, I. A.; Korchagina, A. S.

    2016-09-01

    Heat effects of the dissolution of crystalline γ-aminobutyric acid in water and potassium hydroxide solutions are determined by direct colorimetry at 298.15 K. Standard enthalpies of formation of γ-aminobutyric acid and the products of its dissociation in aqueous solution are calculated.

  4. Photochemical decomposition of perfluorooctanoic acid in aqueous periodate with VUV and UV light irradiation

    International Nuclear Information System (INIS)

    The photochemical decomposition of perfluorooctanoic acid (PFOA) in aqueous periodate (IO4-) was investigated under two types of low-pressure mercury lamps: one emits at 254 nm light (UV light) and the other emits both 254 nm and 185 nm light (VUV light). PFOA decomposed efficiently under VUV light irradiation while it decomposed poorly under UV light irradiation. The addition of IO4- significantly increased the rate of decomposition and defluorination of PFOA irradiated with UV light whereas it decreased both processes under VUV irradiation. Reactive radical (IO3·) generated by photolysis of IO4- initiated the oxidation of PFOA in UV process. Aquated electrons (eaq-), generated from water homolysis, scavenged IO4- resulting in decrease of reactive radical species production and PFOA decomposition. The shorter-chain perfluorocarboxylic acids (PFCAs) formed in a stepwise manner from long-chain PFCAs.

  5. Aldehydes, ketones, and carboxylic acids formed radiolytically in aqueous solutions of cyanides and simple nitriles

    Energy Technology Data Exchange (ETDEWEB)

    Negron-Mendoza, A.; Draganic, Z.D.; Navarro-Gonzalez, R.; Graganic, I.G.

    1983-08-01

    A systematic search for aldehydes, ketones, and carboxylic acids was carried out in aqueous solutions of HCN, NH/sub 4/CN, CH/sub 3/CN, and C/sub 2/H/sub 4/CN, that had received multikilogray doses of /sup 60/Co ..gamma.. radiation. About 30 radiolytic products were identified, among them a large variety of dicarboxylic and tricarboxylic acids. Some of them might be of significant interest in molecular evolution studies of prebiotic processes. They originate in the free-radical-initiated chemical reactions where the additional oligomerization processes are particularly important. Most of the radiolytic products appear in both cyanides and nitriles and point to the importance of reactions involving the carbon-nitrogen triple bond.

  6. Separation of glycols from dilute aqueous solutions via complexation with boronic acids

    Energy Technology Data Exchange (ETDEWEB)

    Randel, L.A.; King, C.J.

    1991-07-01

    This work examines methods of separating low molecular weight glycols from dilute aqueous solution. Extraction into conventional solvents is generally not economical, since, in the literature reviewed, distribution ratios for the two- to four-carbon glycols are all less than one. Distribution ratios can be increased, however, by incorporating into the organic phase an extracting agent that will complex with the solute of interest. The extracting agent investigated in this work is 3-nitrophenylboronic acid (NPBA). NPBA, a boric acid derivative, reversibly complexes with many glycols. The literature on complexation of borate and related compounds with glycols, including mechanistic data, measurement techniques, and applications to separation processes, provides information valuable for designing experiments with NPBA and is reviewed herein. 88 refs., 15 figs., 24 tabs.

  7. Solubility and reactivity of peroxyacetyl nitrate (PAN) in dilute aqueous salt solutions and in sulphuric acid

    Science.gov (United States)

    Frenzel, A.; Kutsuna, S.; Takeuchi, K.; Ibusuki, T.

    The loss rates of PAN in several dilute aqueous salt solutions (NaBr, Na 2SO 3, KI, NaNO 2, FeCl 3, and FeSO 4) and in sulphuric acid were measured at 279 K with a simple bubbler experiment. They are little different from that in pure water. For 5 M sulphuric acid hydrolysis and solubility were determined in the temperature range of 243-293 K. The hydrolysis rate kh=3.2×10 -4 s -1 at 293 K is close to that in water. The observed temperature dependence of the Henry's Law constant H=10- 6.6±0.6exp((4780±420)/T) M atm -1 leads to enthalpy and entropy of solvation Δ Hsolv=-39.7±3.5 kJ mol -1 and Δ Ssolv=-126±11 J mol -1 K -1, respectively.

  8. Influence of charge exchange in acidic aqueous and alcoholic titania dispersions on viscosity.

    Science.gov (United States)

    Rosenholm, Jarl B; Dahlsten, Per

    2015-12-01

    Charging effects resulting from adsorption of acid, acid anions, and protons on titania (anatase) surfaces in anhydrous or mixed alcohol-water dispersions is summarized. The suddenly enhanced conductivity as compared to titania-free solutions has previously been modeled and explained as surface-induced electrolytic dissociation (SIED) of weak acids. This model and recently published results identifying concurrent surface-induced liquid (solvent) dissociation (SILD) are evaluated with experimentally determined conductivity and pH of solutions, zeta-potential of particles, and viscosity of dispersions. Titania (0-25wt%)-alcohol (methanol, ethanol, and propanol) dispersions mixed with (0-100wt%) water were acidified with oxalic, phosphoric, and sulfuric acids. It was found that the experimental results could in many cases be condensed to master curves representing extensive experimental results. These curves reveal that major properties of the systems appear within three concentration regions were different mechanisms (SILD, surface-induced liquid dissociation; SIAD, surface-induced acid dissociation) and charge rearrangement were found to be simultaneously active. In particular, zeta-potential - pH and viscosity - pH curves are in acidified non-polar solvents mirror images to those dependencies observed in aqueous dispersions to which hydroxyl is added. The results suggest that multiple dispersion and adsorption equilibria should be considered in order to characterize the presented exceptionally extensive and complex experimental results. PMID:26520241

  9. Sunlight-initiated chemistry of aqueous pyruvic acid: building complexity in the origin of life.

    Science.gov (United States)

    Griffith, Elizabeth C; Shoemaker, Richard K; Vaida, Veronica

    2013-10-01

    Coupling chemical reactions to an energy source is a necessary step in the origin of life. Here, we utilize UV photons provided by a simulated sun to activate aqueous pyruvic acid and subsequently prompt chemical reactions mimicking some of the functions of modern metabolism. Pyruvic acid is interesting in a prebiotic context due to its prevalence in modern metabolism and its abiotic availability on early Earth. Here, pyruvic acid (CH3COCOOH, a C3 molecule) photochemically reacts to produce more complex molecules containing four or more carbon atoms. Acetoin (CH3CHOHCOCH3), a C4 molecule and a modern bacterial metabolite, is produced in this chemistry as well as lactic acid (CH3CHOHCOOH), a molecule which, when coupled with other abiotic chemical reaction pathways, can provide a regeneration pathway for pyruvic acid. This chemistry is discussed in the context of plausible environments on early Earth such as near the ocean surface and atmospheric aerosol particles. These environments allow for combination and exchange of reactants and products of other reaction environments (such as shallow hydrothermal vents). The result could be a contribution to the steady increase in chemical complexity requisite in the origin of life.

  10. EXAFS study of the speciation of protactinium(V) in aqueous hydrofluoric acid solutions.

    Science.gov (United States)

    De Sio, Stéphanie M; Wilson, Richard E

    2014-12-01

    The speciation of protactinium(V) in hydrofluoric acid (HF) solutions was studied using X-ray absorption spectroscopy. Extended X-ray absorption fine structure measurements were performed on an aqueous solution of 0.05 M protactinium(V) with various HF concentrations ranging from 0.5 to 27 M in order to probe the protactinium coordination sphere with respect to the identity and number of coordinating ligands. The resulting fits to the spectra suggest the presence of an eight-coordinate homoleptic fluoro complex in highly concentrated fluoride solutions (27 M), with equilibrium between seven- and eight-coordinate fluoro complexes at moderate acidities, and in more dilute solutions, results indicate that one water molecule is likely to replace a fluoride in the first coordination sphere, at a distance of 2.54-2.57 Å. Comparisons of this chemistry with group V metals, niobium and tantalum, are presented, and the potential implications for these results on the hydrolytic behavior of protactinium in aqueous systems are discussed.

  11. Process optimization of reaction of acid leaching residue of asbestos tailing and sodium hydroxide aqueous solution

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Silica is the major component of the acid leaching residue of asbestos tailing. The waterglass solution can be prepared by the reaction of the residue with sodium hydroxide aqueous solution. Compared to the high temperature reaction method, this process is environmental friendly and low cost. In this paper, the reaction process of the residue and the sodium hydroxide aqueous solution is optimized. The optimum reaction process parameters are as follows: the usage of sodium hydroxide is 26.4 g/100 g acid leaching residue, the reaction temperature is 90℃, the reaction time is 1 h, and the ratio of the liquid/solid is 2.0. The significance sequence of the process parameters to the alkali leaching reaction effect is the usage of sodium hydroxide > the ratio of the liquid/solid > the reaction time > the reaction temperature. The significance sequence to the leaching ratio of SiO2 is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. The significance sequence to the modulus of the sodium silicate is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. Under the optimum conditions, the leaching ratio of the SiO2 is 77.5%, and the modulus of the sodium silicate is 3.15. The XRD analysis result indicates that the major components of the alkali leaching residue are serpentine, talc, quartz and some albite.

  12. Bile acid-surfactant interactions at the liquid crystal/aqueous interface.

    Science.gov (United States)

    He, Sihui; Liang, Wenlang; Cheng, Kung-Lung; Fang, Jiyu; Wu, Shin-Tson

    2014-07-14

    The interaction between bile acids and surfactants at interfaces plays an important role in fat digestion. In this paper, we study the competitive adsorption of cholic acid (CA) at the sodium dodecyl sulfate (SDS)-laden liquid crystal (LC)/aqueous interface formed with cyanobiphenyl (nCB, n = 5-8) and the mixture of 5CB with 4-(4-pentylcyclohexyl)benzonitrile (5PCH). We find that the critical concentration of CA required to displace SDS from the interface linearly decreases from 160 μM to 16 μM by reducing the alkyl chain length of nCB from n = 8 to n = 5 and from 16 μM to 1.5 μM by increasing the 5PCH concentration from 0 wt% to 19 wt% in the 5PCH-5CB binary mixture. Our results clearly demonstrate that the sensitivity of 5PCH-5CB mixtures for monitoring the interaction between CA and SDS at the LC/aqueous interface can be increased by one order of magnitude, compared to 5CB.

  13. Adsorption of Crystal violet on raw and acid-treated montmorillonite, K10, in aqueous suspension.

    Science.gov (United States)

    Sarma, Gautam Kumar; Sen Gupta, Susmita; Bhattacharyya, Krishna G

    2016-04-15

    Crystal violet is used as a dye in cotton and silk textiles, paints and printing ink. The dye is hazardous and exposure to it may cause permanent injury to the cornea and conjunctiva including permanent blindness, and in severe cases, may lead to respiratory and kidney failure. The present work describes removal of Crystal violet from aqueous solution by adsorption on raw and acid-treated montmorillonite, K10. The clay mineral was treated with 0.25 and 0.50 M sulfuric acid and the resulting materials were characterized by XRD, zeta potential, SEM, FTIR, cation exchange capacity, BET surface area and pore volume measurements. The influences of pH, interaction time, adsorbent amount, and temperature on adsorption were monitored and explained on the basis of physico-chemical characteristics of the materials. Basic pH generally favors adsorption but considerable removal was possible even under neutral conditions. Adsorption was very rapid and equilibrium could be attained in 180 min. The kinetics conformed to second order model. Langmuir monolayer adsorption capacity of raw montmorillonite K10 was 370.37 mg g(-1) whereas 0.25 M and 0.50 M acid treated montmorillonite K10 had capacities of 384.62 and 400.0 mg g(-1) respectively at 303 K. Adsorption was exothermic and decreased in the temperature range of 293-323 K. Thermodynamically, the process was spontaneous with Gibbs energy decreasing with rise in temperature. The results suggest that montmorillonite K10 and its acid treated forms would be suitable for removing Crystal violet from aqueous solution. PMID:26866669

  14. Adsorption of Crystal violet on raw and acid-treated montmorillonite, K10, in aqueous suspension.

    Science.gov (United States)

    Sarma, Gautam Kumar; Sen Gupta, Susmita; Bhattacharyya, Krishna G

    2016-04-15

    Crystal violet is used as a dye in cotton and silk textiles, paints and printing ink. The dye is hazardous and exposure to it may cause permanent injury to the cornea and conjunctiva including permanent blindness, and in severe cases, may lead to respiratory and kidney failure. The present work describes removal of Crystal violet from aqueous solution by adsorption on raw and acid-treated montmorillonite, K10. The clay mineral was treated with 0.25 and 0.50 M sulfuric acid and the resulting materials were characterized by XRD, zeta potential, SEM, FTIR, cation exchange capacity, BET surface area and pore volume measurements. The influences of pH, interaction time, adsorbent amount, and temperature on adsorption were monitored and explained on the basis of physico-chemical characteristics of the materials. Basic pH generally favors adsorption but considerable removal was possible even under neutral conditions. Adsorption was very rapid and equilibrium could be attained in 180 min. The kinetics conformed to second order model. Langmuir monolayer adsorption capacity of raw montmorillonite K10 was 370.37 mg g(-1) whereas 0.25 M and 0.50 M acid treated montmorillonite K10 had capacities of 384.62 and 400.0 mg g(-1) respectively at 303 K. Adsorption was exothermic and decreased in the temperature range of 293-323 K. Thermodynamically, the process was spontaneous with Gibbs energy decreasing with rise in temperature. The results suggest that montmorillonite K10 and its acid treated forms would be suitable for removing Crystal violet from aqueous solution.

  15. Removal of Basic Dyes from Aqueous Solution by Chloroacetic Acid Modified Ferula Communis Based Adsorbent: Thermodynamic and Kinetic Studies

    OpenAIRE

    Salih, Shameran Jamal

    2014-01-01

    ABSTRACT: This research aimed to propose an alternative cheap and abundantly available adsorbent (Ferula communis) for the removal of basic dyes from aqueous solutions. Chloroacetic acid modified Ferula communis (MFC) shows a great potential for the removal of basic red 9 dyes (BR9) from aqueous solution with the effects of solution capacity under pH, temperature, contact time, adsorbent dosage, and initial dye concentration condition on BR9 removal were examined. The adsorption equilibrium d...

  16. A stable liquid–liquid extraction system for clavulanic acid using polymer-based aqueous two-phase systems

    OpenAIRE

    Pereira, Jorge F. B.; Santos, Valéria Carvalho; Johansson, Hans-Olof; J. A. Teixeira; Pessoa Júnior, Adalberto

    2012-01-01

    The partitioning of Clavulanic Acid (CA) in a novel inexpensive and stable aqueous two-phase system (ATPS) composed by poly(ethylene glycol) (PEG) and sodium polyacrylate (NaPA) has been studied. The aqueous two-phase systems are formed by mixing both polymers with a salt (NaCl or Na2SO4) and an aqueous solution of CA. The stability of CA on the presence of both polymers was investigated and it was observed that these polymers do not degrade the biomolecule. The effect of PEG-molecular ...

  17. Thermodynamic modeling of acidic gas solubility in aqueous solutions of MEA, MDEA and MEA-MDEA blends

    DEFF Research Database (Denmark)

    Vrachnos, Ath.; Kontogeorgis, Georgios; Voutsas, EC

    2006-01-01

    The thermodynamic framework that was developed in a previous work [Vrachnos et al. Ind. Eng. Chem. Res. 2004, 43, 2798] for the description of chemical and vapor-liquid equilibria of carbon dioxide, hydrogen sulfide, and their mixtures in aqueous methyldiethanolamine (MDEA) solutions is revised...... and extended in this study to the absorption of carbon dioxide into aqueous monoethanolamine (MEA) solutions and aqueous MDEA-MEA blends. The results of the model are compared with experimental data taken from the literature. Very satisfactory predictions of acidic gas vapor-liquid equilibrium over MDEA, MEA...

  18. Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid

    Directory of Open Access Journals (Sweden)

    Y. Tan

    2011-06-01

    Full Text Available Previous experiments have demonstrated that the aqueous OH radical oxidation of methylglyoxal produces low volatility products including oxalate and oligomers. These products are found predominantly in the particle phase in the atmosphere, suggesting that methylglyoxal is a precursor of secondary organic aerosol (SOA. Acetic acid is an important intermediate in aqueous methylglyoxal oxidation and a ubiquitous product of gas phase photochemistry, making it a potential "aqueous" SOA precursor in its own right. Altieri et al. (2008 proposed that acetic acid was the precursor of oligoesters observed in methylglyoxal oxidation. However, the fate of acetic acid upon aqueous-phase oxidation is not well understood. In this research, acetic acid at concentrations relevant to atmospheric waters (20 μM–10 mM was oxidized by OH radical. Products were analyzed by ion chromatography (IC, electrospray ionization mass spectrometry (ESI-MS, and IC-ESI-MS. The formation of glyoxylic, glycolic, and oxalic acids were observed. In contrast to methylglyoxal oxidation, succinic acid and oligomers were not detected. Using results from these and methylglyoxal + OH radical experiments, radical mechanisms responsible for oligomer formation from methylglyoxal oxidation in clouds and wet aerosols are proposed. The importance of acetic acid/acetate as an SOA precursor is also discussed. We hypothesize that this and similar chemistry is central to the daytime formation of oligomers in wet aerosols.

  19. Partition of Chiral pharmaceutical intermediate R(-)-Mandelic Acid in Aqueous Two-Phase System of Poly(ethylene glycol)-Ammonium Sulfate

    Institute of Scientific and Technical Information of China (English)

    Xu Xiaoping; Li Zhongqin; Chen Jiebo; Huang Xinghua

    2004-01-01

    An aqueous two-phase system of poly (ethylene glycol)-ammonium sulfate was employed to separate R (-)-mandelic acid.The result showed that R (-)-mandelic acid has priority to partition in PEG-rich top phase. This indicated that aqueous two-phase is a very suitable system for separation of R(-)-mandelic acid.

  20. Deprotonation of salicylic acid and 5-nitrosalicylic acid in aqueous solutions of ethanol

    Directory of Open Access Journals (Sweden)

    Faraji Mohammad

    2011-01-01

    Full Text Available The protonation constant values of two hydroxybenzoic acids (salicylic and 5-nitrosalicylic acid were studied in some water-ethanol solutions using spectrophotometric and potentiometric methods at 25°C and in an ionic strength of 0.1 M sodium perchlorate. The results indicated that the pKa values increase with increasing proportion of ethanol in mixed solvent. The dependence of the protonation constants on the variation of the solvent were correlated by the dielectric constants of the media. Furthermore, for a better understanding of the solvent influence, the obtained results were explained in terms of the Kamlet-Taft parameters α (hydrogen-bond donor acidity, π

  1. Pulse electrodeposition of Pt and Pt–Ru methanol-oxidation nanocatalysts onto carbon nanotubes in citric acid aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Huei-Yu [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China); Hsieh, Chien-Kuo [Department of Materials Engineering, Ming Chi University of Technology, New Taipei City 24301, Taiwan, ROC (China); Tsai, Ming-Chi; Wei, Yu-Hsuan; Yeh, Tsung-Kuang [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China); Tsai, Chuen-Horng, E-mail: tsai@aec.gov.tw [Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC (China)

    2015-06-01

    In this study, platinum nanoparticle/carbon nanotube (Pt NP/CNT) and platinum–ruthenium nanoparticle (Pt–Ru NP/CNT) hybrid nanocatalysts were prepared by the pulse-electrodeposition method in different aqueous solutions containing citric acid (CA) or sulfuric acid (SA). The electrocatalytic properties of the Pt NP/CNT and Pt–Ru NP/CNT electrodes prepared using different aqueous solutions were investigated for methanol oxidation. The results show that the electrochemical mass activities of these hybrid nanocatalysts prepared in the CA aqueous solution were increased by factors of 1.46 and 2.77 for Pt NPs and Pt–Ru NPs, respectively, compared with those prepared in SA aqueous solutions using the same procedure. These increased mass activities are attributed to the CA playing dual roles as both a stabilizing agent and a particle size reducing agent in the aqueous solutions. The approach developed in this work enables further reductions in the particle sizes of noble-metal nanocatalysts. - Highlights: • Pulse-electrodeposition of Pt or Pt–Ru nanoparticles on carbon nanotubes • Carbon nanotubes used as a catalyst-supporting material • Citric acid used as reducing agent in the aqueous electrodeposition solutions • Electrochemical activity for methanol oxidation improved by a factor of 1.46 to 2.77.

  2. STRUCTURE AND REDOX TRANSFORMATIONS OF IRON(III COMPLEXES WITH SOME BIOLOGICALLY IMPORTANT INDOLE-3-ALKANOIC ACIDS IN AQUEOUS SOLUTIONS

    Directory of Open Access Journals (Sweden)

    Krisztina Kovács

    2007-06-01

    Full Text Available Interactions of a series of indole-3-alkanoic acids (with n-alkanoic acid side-chains from C1 to C4 with iron(III in acidic aqueous solutions have been shown to comprise two parallel processes including complexation and redox transformations giving iron(II hexaaquo complexes. The structure and composition of the reaction products are discussed, as analysed using a combination of instrumental techniques including 57Fe Mössbauer, vibrational and HNMR spectroscopies.

  3. Removal of fluoride in aqueous solution by adsorption on acid activated water treatment sludge

    Science.gov (United States)

    Vinitnantharat, Soydoa; Kositchaiyong, Sriwilai; Chiarakorn, Siriluk

    2010-06-01

    This paper reports the use of a pellet of adsorbent made from water treatment sludge (S) and acid activated water treatment sludge (SH) for removal of fluoride in the batch equilibration technique. The influence of pH, adsorbent dosage, temperature and effect of other ions were employed to find out the feasibility of acid activated adsorbent to remove fluoride to the permissible concentration of 0.7 mg/L. The results from the adsorption isotherm followed both Langmuir and Freundlich models and the highest fluoride removal was found for adsorbent activated with acetic acid at 2.0 mol/L. The optimum adsorbent dosage was found at 40 g/L, 0.01 mol/L acid activated adsorbent which was able to adsorb fluoride from 10 down to 0.11 mg/L. The adsorption capacity was decreased when the temperature increased. This revealed that the adsorption of fluoride on SH was exothermic. In the presence of nitrate and carbonate ions in the aqueous solution, fluoride removal efficiency of SH decreased from 94.4% to 86.6% and 90.8%, respectively. However, there is no significant effect in the presence of sulfate and chloride ions.

  4. Inhibition of ice crystallisation in highly viscous aqueous organic acid droplets

    Directory of Open Access Journals (Sweden)

    B. J. Murray

    2008-09-01

    Full Text Available Homogeneous nucleation of ice within aqueous solution droplets and their subsequent crystallisation is thought to play a significant role in upper tropospheric ice cloud formation. It is normally assumed that homogeneous nucleation will take place at a threshold supersaturation, irrespective of the identity of the solute, and that rapid growth of ice particles will follow immediately after nucleation. However, it is shown here through laboratory experiments that droplets may not readily freeze in the very cold tropical tropopause layer (TTL, typical temperatures of 186–200 K. In these experiments ice crystal growth in citric acid solution droplets did not occur when ice nucleated below 197±6 K. Citric acid, 2-hydroxypropane-1,2,3-tricarboxyllic acid, is a molecule with similar functionality to oxygenated organic compounds which are ubiquitous in atmospheric aerosol. It is therefore thought to be a sensible proxy for atmospheric organic material. Evidence is presented that suggests citric acid solution droplets become ultra-viscous and form glassy solids under atmospherically relevant conditions. Diffusion of liquid water molecules to ice nuclei is expected to be very slow in ultra-viscous solution droplets and nucleation is negligible in glassy droplets; this most likely provides an explanation for the experimentally observed inhibition of ice crystallisation. The implications of ultra-viscous and glassy solution droplets for ice cloud formation and supersaturations in the TTL are discussed.

  5. Biosorption of Acid Yellow 17 from aqueous solution by non-living aerobic granular sludge

    International Nuclear Information System (INIS)

    Batch biosorption experiments were carried out for the removal of Acid Yellow 17 from aqueous solution using non-living aerobic granular sludge as an effective biosorbent. The effects of solution pH value, biosorbent dosage, initial Acid Yellow 17 concentration, NaCl concentration and temperature on the biosorption were investigated. The experimental results indicate that this process was highly dependent on pH value and the pH value of 2.0 was favorable. The Temkin isotherm was more applicable for describing the biosorption equilibrium at the whole concentration range than the Freundlich and Langmuir isotherm. The results of kinetics study show that the pseudo-second-order model fitted to the experimental data well. Both intraparticle diffusion and boundary layer diffusion might affect the biosorption rate. Thermodynamic studies demonstrate that the biosorption process was spontaneous and exothermic. The FTIR analysis before and after Acid Yellow 17 binding indicated that functional groups such as amine, hydroxyl, carboxyl and either on the non-living aerobic granular sludge would be the active binding sites for the biosorption of the studied dye. These results show that non-living aerobic granular sludge could be effectively used as a low-cost and alternative biosorbent for the removal of Acid Yellow 17 dye from wastewater.

  6. Inhibition of ice crystallisation in highly viscous aqueous organic acid droplets

    Directory of Open Access Journals (Sweden)

    B. J. Murray

    2008-05-01

    Full Text Available Homogeneous nucleation of ice within aqueous solution droplets and their subsequent crystallisation is thought to play a significant role in upper tropospheric ice cloud formation. It is normally assumed that homogeneous nucleation will take place at a threshold supersaturation, irrespective of the identity of the solute, and that rapid growth of ice particles will follow immediately after nucleation. However, it is shown here through laboratory experiments that droplets may not readily freeze in the very cold tropical tropopause layer (TTL, typical temperatures of 186–200 K. In these experiments ice crystal growth in citric acid solution droplets did not occur when ice nucleated below 197±6 K. Citric acid, 2-hydroxypropane-1,2,3-tricarboxyllic acid, is a molecule with similar functionality to oxygenated organic compounds which are ubiquitous to atmospheric aerosol and is therefore thought to be a sensible proxy for atmospheric organic material. Evidence is presented that suggest citric acid solution droplets become ultra-viscous or perhaps even glassy under atmospherically relevant conditions. Diffusion of liquid water molecules to ice nuclei is expected to be very slow in ultra-viscous solution droplets and this most likely provides an explanation for the experimentally observed inhibition of ice crystallisation. The implications of ultra-viscous solution droplets for ice cloud formation and supersaturations in the TTL are discussed.

  7. Reactivity of Alanylalanine Diastereoisomers in Neutral and Acid Aqueous Solutions: a Versatile Stereoselectivity

    Science.gov (United States)

    Plasson, Raphaël; Tsuji, Maika; Kamata, Masazumi; Asakura, Kouichi

    2011-10-01

    A good comprehension of the reactivity of peptides in aqueous solution is fundamental in prebiotic chemistry, namely for understanding their stability and behavior in primitive oceans. Relying on the stereoselectivity of the involved reactions, there is a huge interest in amino acid derivatives for explaining the spontaneous emergence of homochirality on primitive Earth. The corresponding kinetic and thermodynamic parameters are however still poorly known in the literature. We studied the reactivity of alanylalanine in acidic to neutral conditions as a model system. The hydrolysis into amino acids, the epimerization of the N-terminal residue, and the cyclization into diketopiperazine could be successfully identified and studied. This kinetic investigation highlighted interesting behaviors. Complex mechanisms were observed in very acidic conditions. The relative kinetic stability of the diastereoisomers of the dipeptide is highly dependent of the pH, with the possibility to dynamically destabilize the thermodynamically more stable diastereoisomers. The existence of the cyclization of dipeptides adds complexity to the system. On one hand it brings additional stereoselectivities; on the other hand fast racemization of heterochiral dipeptides is obtained.

  8. Acidity control of the oxidation reactions induced by non-thermal plasma treatment of aqueous effluents in pollutant abatement processes

    International Nuclear Information System (INIS)

    The acid properties of a non-thermal plasma in humid air (e.g., a gliding arc device) induced in an aqueous solution may deeply affect the efficiency of the matching oxidising properties, especially when the aqueous targets involve organic solutes. Hence, their oxidation rate may be strongly modified. A series of buffers is proposed to control the pH of aqueous target for at least one-hour treatments. The selected acid-base systems were selected for their inertia towards oxidation reaction, to cover a very large range of acidity. The reported results are essential from both fundamental and applied points of view. They first allow the acute controlling of the degradation rate of organic compounds. They also enable estimating the efficiency of the gliding arc treatments in environmental applications. Besides, they allow getting reliable data on the bactericidal effect on the plasma treatments, which are a merging application of the electric discharges. (author)

  9. Kinetics of Formic Acid-autocatalyzed Preparation of Performic Acid in Aqueous Phase

    Institute of Scientific and Technical Information of China (English)

    孙晓英; 赵雪冰; 杜伟; 刘德华

    2011-01-01

    Performic acid (PFA) is an oxidant used in chemical processing, synthesis and bleaching. The macro kinetic models of synthesis, hydrolysis and decomposition of PFA were investigated via formic acid-autocatalyzed reaction. It was found that the intrinsic activation energies of PFA synthesis and hydrolysis were 75.2 kJ·mol^-1 and 40.4 kJ·mol^-1 respectively. The observed activation energy of PFA decomposition was 95.4 kJ·mol^-1. The experi-mental results indicated that the decomposition of PFA was liable to occur even at the ambient temperature. Both the spontaneous decomposition and the radical-introduced decomposition contributed to the decomposition of PFA.

  10. Red blood cell oleic acid levels reflect olive oil intake while omega-3 levels reflect fish intake and the use of omega-3 acid ethyl esters: The Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-Heart Failure trial.

    Science.gov (United States)

    Harris, William S; Masson, Serge; Barlera, Simona; Milani, Valentina; Pileggi, Silvana; Franzosi, Maria Grazia; Marchioli, Roberto; Tognoni, Gianni; Tavazzi, Luigi; Latini, Roberto

    2016-09-01

    The Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-Heart Failure (GISSI-HF) study reported benefits of n-3 fatty acid (FA) treatment on cardiovascular (CV) events, but the effects of treatment on a putative CV disease risk factor, the red blood cell (RBC) n-3 FA level (the omega-3 index), have not been examined in this context. We hypothesized that treatment with prescription omega-3 acid ethyl esters (O3AEE) would increase the omega-3 index to the proposed cardioprotective value of 8%. RBCs were collected from a subset of patients participating in the GISSI-HF study (n=461 out of 6975 randomized), at baseline and after 3 months of treatment with either an olive oil placebo or O3AEE (1 g/d). RBC FA levels were expressed as a percentage of total FA. Patients also reported their typical olive oil and fish intakes. RBC oleic acid levels were directly correlated with reported frequency of olive oil consumption, and the omega-3 index was correlated with reported fish intake (P for trends <0.001 for both). After treatment, the omega-3 index increased from 4.8±1.7% to 6.7±1.9% but was unchanged in the placebo group (4.7±1.7 to 4.8±1.5%) (P<.0001 for changes between groups). At 3 months, more patients reached the proposed target omega-3 index level of 8%-12% in the treated vs placebo group (22.6% vs. 1.3%, P<.0001), however, what omega-3 index levels were ultimately achieved after four years in this trial are unknown. PMID:27632919

  11. Volumetric behaviour of amino acids and their group contributions in aqueous lactose solutions at different temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Amalendu, E-mail: palchem@sify.co [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India); Chauhan, Nalin [Department of Chemistry, Kurukshetra University, Kurukshetra 136 119 (India)

    2011-02-15

    Densities, {rho}, for glycine, L-alanine, L-valine, and L-leucine [(0.05 to 0.30) m] in aqueous lactose solutions ranging from pure water to 6 mass% lactose were determined at T = (293.15, 298.15, 303.15, and 308.15) K. The density was used to compute apparent molar volume, V{sub {phi}}, partial molar volume at infinite dilution, V{sub {phi}}{sup o}, and experimental slope, S{sub V} were obtained and interpreted in terms of solute-solvent and solute-solute interactions. These data were used to calculate the ({partial_derivative}V{sub {phi}}{sup 0}/{partial_derivative}T){sub P} values. The partial molar volume of transfer, {Delta}V{sub {phi}}{sup 0} from water to aqueous lactose solutions at infinite dilution has also been calculated. In addition to this, the linear correlation of V{sub {phi}}{sup 0} with number of carbon atoms in the alkyl chain of amino acids was utilized to determine the respective contributions of NH{sub 3}{sup +}COO{sup -}, and CH{sub 2} groups to V{sub {phi}}{sup 0}.

  12. Aqueous chlorination of mefenamic acid: kinetics, transformation by-products and ecotoxicity assessment.

    Science.gov (United States)

    Adira Wan Khalit, Wan Nor; Tay, Kheng Soo

    2016-05-18

    Mefenamic acid (Mfe) is one of the most frequently detected nonsteroidal anti-inflammatory drugs in the environment. This study investigated the kinetics and the transformation by-products of Mfe during aqueous chlorination. The potential ecotoxicity of the transformation by-products was also evaluated. In the kinetic study, the second-order rate constant (kapp) for the reaction between Mfe and free available chlorine (FAC) was determined at 25 ± 0.1 °C. The result indicated that the degradation of Mfe by FAC is highly pH-dependent. When the pH was increased from 6 to 8, it was found that the kapp for the reaction between Mfe and FAC was decreased from 16.44 to 4.4 M(-1) s(-1). Characterization of the transformation by-products formed during the chlorination of Mfe was carried out using liquid chromatography-quadrupole time-of-flight accurate mass spectrometry. Four major transformation by-products were identified. These transformation by-products were mainly formed through hydroxylation, chlorination and oxidation reactions. Ecotoxicity assessment revealed that transformation by-products, particularly monohydroxylated Mfe which is more toxic than Mfe, can be formed during aqueous chlorination.

  13. Molecular interactions of α-amino acids insight into aqueous β-cyclodextrin systems.

    Science.gov (United States)

    Ekka, Deepak; Roy, Mahendra Nath

    2013-10-01

    Qualitative and quantitative analysis of molecular interaction prevailing in glycine, L-alanine, L-valine and aqueous solution of β-cyclodextrin (β-CD) have been probed by thermophysical properties. Density (ρ), viscosity (η), and ultrasonic speed (u) measurements have been reported at different temperatures. The extent of interaction (solute-solvent interaction) is expressed in terms of the limiting apparent molar volume ([Formula: see text]), viscosity B-coefficient and limiting apparent molar adiabatic compressibility ([Formula: see text]). The changes on the enthalpy ([Formula: see text]) and entropy ([Formula: see text]) of the encapsulation analysis give information about the driving forces governing the inclusion. The temperature dependence behaviour of partial molar quantities and group contributions to partial molar volumes has been determined for the amino acids. The trends in transfer volumes, [Formula: see text], have been interpreted in terms of solute-cosolute interactions based on a cosphere overlap model. The role of the solvent (aqueous solution of β-CD) and the contribution of solute-solute and solute-solvent interactions to the solution complexes have also been analyzed through the derived properties.

  14. Oenocarpus bataua Mart. (Arecaceae) : rediscovering a source of high oleic vegetable oil from Amazonia

    OpenAIRE

    Montufar, R.; Laffargue, Andreina; Pintaud, Jean-Christophe; Hamon, Serge; Avallone, Sylvie; Dussert, Stéphane

    2010-01-01

    The fatty acid (FA) composition of Oenocarpus bataua oil from 38 samples collected over a large geographical range (i.e. French Guiana and Peru) was analyzed. Fifteen fatty acids were obtained from the mesocarp of this palm species. Oleic (72.7%) and palmitic (18.1%) acids were the predominant FAs. Minor FAs were cis-vaccenic acid (2.3%), linoleic acid (1.9%), stearic acid (1.7%), palmitoleic (0.9%) and alpha-linolenic acid (0.8%). The mean lipid content of the dry mesocarp was 51.6%. The O. ...

  15. Extraction of nitric acid, uranyl nitrate, and bismuth nitrate from aqueous nitric acid solutions with CMPO

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, B.B.

    1995-08-01

    DOE sponsored development of the transuranium extraction (TRUEX) process for removing actinides from radioactive wastes. The solvent is a mixture of CMPO and TBP. Since the extraction characteristics of CMPO are not as well understood as those of TBP, the extraction of nitric acid, uranyl nitrate, and bismuth nitrate with CMPO (dissolved in n-dodecane) were studied. Results indicate that CMPO extracts nitric acid with a 1:1 stoichiometry; equilibrium constant is 2. 660{plus_minus}0.092 at 25 C, and extraction enthalpy is -5. 46{plus_minus}0.46 kcal/mol. Slope analysis indicates that uranyl nitrate extracts with a mixed equilibria of 1:1 and 2:1 stoichiometries in nearly equal proportion. Equil. constant of the 2: 1 extraction was 1.213 {times} 10{sup 6}{plus_minus}3.56 {times} 10{sup 4} at 25 C; reaction enthalpy was -9.610{plus_minus}0.594 kcal/mol. Nitration complexation constant is 8.412{plus_minus}0.579, with an enthalpy of -10.72{plus_minus}1.87 kcal/mol. Bismuth nitrate also extracts with a mixed equilibria of (perhaps) 1:1 and 2:1 stoichiometries. A 2:1 extraction equilibrium and a nitrate complexation adequately model the data. Kinetics and enthalpies were also measured.

  16. Extraction of nitric acid, uranyl nitrate, and bismuth nitrate from aqueous nitric acid solutions with CMPO

    International Nuclear Information System (INIS)

    DOE sponsored development of the transuranium extraction (TRUEX) process for removing actinides from radioactive wastes. The solvent is a mixture of CMPO and TBP. Since the extraction characteristics of CMPO are not as well understood as those of TBP, the extraction of nitric acid, uranyl nitrate, and bismuth nitrate with CMPO (dissolved in n-dodecane) were studied. Results indicate that CMPO extracts nitric acid with a 1:1 stoichiometry; equilibrium constant is 2. 660±0.092 at 25 C, and extraction enthalpy is -5. 46±0.46 kcal/mol. Slope analysis indicates that uranyl nitrate extracts with a mixed equilibria of 1:1 and 2:1 stoichiometries in nearly equal proportion. Equil. constant of the 2: 1 extraction was 1.213 x 106±3.56 x 104 at 25 C; reaction enthalpy was -9.610±0.594 kcal/mol. Nitration complexation constant is 8.412±0.579, with an enthalpy of -10.72±1.87 kcal/mol. Bismuth nitrate also extracts with a mixed equilibria of (perhaps) 1:1 and 2:1 stoichiometries. A 2:1 extraction equilibrium and a nitrate complexation adequately model the data. Kinetics and enthalpies were also measured

  17. Electrochemical oxidation of loop diuretic furosemide in aqueous acid medium and its analytical application

    Directory of Open Access Journals (Sweden)

    Shikandar D. Bukkitgar

    2016-12-01

    Full Text Available An investigation of oxidative–reductive mechanisms of pharmaceutically important molecules gives us information about the metabolic fact of targeted drug. As compared to recent ongoing, time-consuming and costly techniques, there is an urgent needing for development of a sensitive technique, which can help easy understanding of these pathways. Therefore, in the present work, an effective, low-cost and time-saving technique to investigate the reaction mechanism of furosemide in aqueous acid medium is attempted. Furosemide undergoes two-proton and two-electron transfer reaction. The product obtained was analysed by UV spectra. It was found that the chemical oxidation and electrochemical oxidation of furosemide follows two different pathways. In addition, an effective technique has been developed to determine furosemide in its trace level. Good recoveries and low detection limit accomplished the magnitude of the proposed method. The proposed method was adopted for furosemide determination in human urine and pharmaceutical samples.

  18. Solubility and metastable zone width of DL-tartaric acid in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiang-Yang; Wang, Xiaofang; Hao, Lin; Yang, Xiaowu; Dang, Leping; Wei, Hongyuan [School of Chemical Engineering and Technology, Tianjin University, 300072 Tianjin (China)

    2012-11-15

    Solubility and metastable zone width (MSZW) of DL-tartaric acid (DL-TA) in aqueous solution have been determined. Solubility of DL-TA was measured in the temperature range from 0 to 50 C at atmospheric pressure by means of the conventional polythermal method using Turbidity Monitoring Technique, which was verified by a gravimetric method. The dissolution enthalpy and entropy of DL-TA were then calculated from the solubility data using van't Hoff equation. Two approaches was used to estimate the nucleation kinetics from the measured metastable zone width data, the self-consistent approach and the approach based on 3D nucleation. In addition, the metastable zone width slightly decreases with increasing agitation rate and was independent of working volume. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Removal of Basic Violet 14 from aqueous solution using sulphuric acid activated materials.

    Science.gov (United States)

    Suresh, S

    2016-01-01

    In this study the adsorption of Basic Violet, 14 from aqueous solution onto sulphuric acid activated materials prepared from Calophyllum inophyllum (CS) and Theobroma cacao (TS) shells were investigated. The experimental data were analysed by Langmuir, Freundlich and Temkin isotherm models. The results showed that CS has a superior adsorption capacity compared to the TS. The adsorption capacity was found to be 1416.43 mg/g for CS and 980.39 mg/g for TS. The kinetic data results at different concentrations were analysed using pseudo first-order and pseudo-second order model. Boyd plot indicates that the dye adsorption onto CS and TS is controlled by film diffusion. The adsorbents were characterised by scanning electron microscopy. The materials used in this study were economical waste products and hence can be an attractive alternative to costlier adsorbents for dye removal in industrial wastewater treatment processes. PMID:27330899

  20. Interpolymer reactions of nonionic polymers with polyacrylic acid in aqueous solutions

    Directory of Open Access Journals (Sweden)

    E. Shaikhutdinov

    2012-03-01

    Full Text Available Results of fundamental investigations in the intermacromolecular reactions and interpolymer complexes to be performed by authors with co-workes within last 20 years have been intergrated and summarized in the present review. The raw of fundamental regularities in the effect of factors of different nature (pH, ionic strength, temperature, hydrophilic-hydrophobic balance of macrochain, etc. on the complexation of nonionic polymers with polycarboxylic acids in aqueous solutions has been revealed. Critical pH upon complexation (pHcrit. has been used for evaluation of the complexing ability of the polymers. It was shown tha tdepending on pHcrit. all systems can be divided into 2 groups, namely, weak complexing and strongly complexing. The existence of two critical pH upon complexation responsible for formation typical interpolymer complexes and hydrophilic associations has been demonstrated by the method of luminescence spectroscopy.

  1. Optical properties of colloidal aqueous synthesized 3 mercaptopropionic acid stabilized CdS quantum dots

    Science.gov (United States)

    Sumanth Kumar, D.; Jai Kumar, B.; Mahesh H., M.

    2016-05-01

    We have explored an easiest and simplest aqueous route to synthesize bright green luminescent CdS QDs using 3-Mercaptopropionic acid (MPA) as a stabilizer in air ambient for solar cell applications. The CdS quantum dots showed a strong quantum confinement effect with good stability, size and excellent photoluminescence. MPA Capping on CdS QDs was confirmed through FTIR. The Optical absorption spectrum revealed the CdS quantum dots are highly transparent in the visible region with absorption peak at 380 nm, confirming the quantum confinement. Photoluminescence showed an emission peak at 525 nm wavelength. The optical band gap energy was found to be 3.19 eV and CdS quantum dots radius calculated using Brus equation is 1.5 nm. The results are presented and discussed in detail.

  2. Cementation and Aqueous Alteration of a Sandstone Unit Under Acidic Conditions in Gale Crater, Mars

    Science.gov (United States)

    Yen, A. S.; Blake, D. F.; Ming, D. W.; Morris, R. V.; Gellert, R.; Clark, B.; Vaniman, D. T.; Chipera, S. J.; Thompson, L. M.; Bristow, T. F.; Rampe, E. B.; Crisp, J. A.

    2016-01-01

    The Curiosity rover landed on Mars in August 2012 to explore the sedimentary history and to assess the habitability of Gale Crater. After 1200 sols of surface operations and over 12 km of traverse distance, the mineralogy of 10 samples has been determined by the CheMin X-ray diffractometer (XRD) and the chemical composition of nearly 300 targets has been established by the Alpha Particle X-ray Spectrometer (APXS). Light-toned fracture zones containing elevated concentrations of silica have been studied by Curiosity's instruments to determine the nature of the fluids that resulted in the enrichment of SiO2. Multiple fluid exposures are evident, and the chemistry and mineralogy data indicate at least two aqueous episodes may have occurred under acidic conditions.

  3. Treatment of sugi (Cryptomeria japonica D.) sapwood with aqueous solution of acetic acid

    Institute of Scientific and Technical Information of China (English)

    LUBao-wang; DUGuang-hua; MATSUITakanao; MATSUSHITAYoh-ichi

    2003-01-01

    Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.

  4. Biodegradable hyaluronic acid hydrogels to control release of dexamethasone through aqueous Diels–Alder chemistry for adipose tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Ming; Ma, Ye; Zhang, Ziwei; Mao, Jiahui [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing (China); Tan, Huaping, E-mail: hptan@njust.edu.cn [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing (China); Hu, Xiaohong [School of Material Engineering, Jinling Institute of Technology, Nanjing (China)

    2015-11-01

    A robust synthetic strategy of biopolymer-based hydrogels has been developed where hyaluronic acid derivatives reacted through aqueous Diels–Alder chemistry without the involvement of chemical catalysts, allowing for control and sustain release of dexamethasone. To conjugate the hydrogel, furan and maleimide functionalized hyaluronic acid were synthesized, respectively, as well as furan functionalized dexamethasone, for the covalent immobilization. Chemical structure, gelation time, morphologies, swelling kinetics, weight loss, compressive modulus and dexamethasone release of the hydrogel system in PBS at 37 °C were studied. The results demonstrated that the aqueous Diels–Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for hydrogel conjugation and covalent immobilization of dexamethasone. Cell culture results showed that the dexamethasone immobilized hydrogel was noncytotoxic and preserved proliferation of entrapped human adipose-derived stem cells. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gel scaffolds with ideal structures for adipose tissue engineering, which provides a competitive alternative to conventional conjugation techniques such as copper mediated click chemistry. - Highlights: • A biodegradable hyaluronic acid hydrogel was crosslinked via aqueous Diels–Alder chemistry. • Dexamethasone was covalently immobilized into the hyaluronic acid hydrogel via aqueous Diels–Alder chemistry. • Dexamethasone could be released from the Diels–Alder hyaluronic acid hydrogel in a controlled fashion.

  5. Biodegradable hyaluronic acid hydrogels to control release of dexamethasone through aqueous Diels–Alder chemistry for adipose tissue engineering

    International Nuclear Information System (INIS)

    A robust synthetic strategy of biopolymer-based hydrogels has been developed where hyaluronic acid derivatives reacted through aqueous Diels–Alder chemistry without the involvement of chemical catalysts, allowing for control and sustain release of dexamethasone. To conjugate the hydrogel, furan and maleimide functionalized hyaluronic acid were synthesized, respectively, as well as furan functionalized dexamethasone, for the covalent immobilization. Chemical structure, gelation time, morphologies, swelling kinetics, weight loss, compressive modulus and dexamethasone release of the hydrogel system in PBS at 37 °C were studied. The results demonstrated that the aqueous Diels–Alder chemistry provides an extremely selective reaction and proceeds with high efficiency for hydrogel conjugation and covalent immobilization of dexamethasone. Cell culture results showed that the dexamethasone immobilized hydrogel was noncytotoxic and preserved proliferation of entrapped human adipose-derived stem cells. This synthetic approach uniquely allows for the direct fabrication of biologically functionalized gel scaffolds with ideal structures for adipose tissue engineering, which provides a competitive alternative to conventional conjugation techniques such as copper mediated click chemistry. - Highlights: • A biodegradable hyaluronic acid hydrogel was crosslinked via aqueous Diels–Alder chemistry. • Dexamethasone was covalently immobilized into the hyaluronic acid hydrogel via aqueous Diels–Alder chemistry. • Dexamethasone could be released from the Diels–Alder hyaluronic acid hydrogel in a controlled fashion

  6. Effects of ultrasonic processing on degradation of salvianolic acid B in aqueous solution.

    Science.gov (United States)

    Guo, Y X; Zhang, L; Lu, L; Liu, E H; Shi, C Z

    2016-09-10

    To evaluate the stability of salvianolic acid B (Sal B) under ultrasound-assisted extraction in the pharmaceutical industry, degradation of Sal B under ultrasonic irradiation was investigated as the function of buffer concentration, pH, and temperature. With regard to Sal-B concentration, a first-order degradation process was determined, with 10% change in assay from its initial concentration as t90=4.81h, under maximum stability acidic conditions (pH 2.0) and at 25°C. The logkpH-pH profile described by specific acid-base catalysis and water molecules supported the experimental results. Liquid chromatography-mass spectrometry (LC-MS) analyses revealed 7 major degradation products whose structures were characterized by electrospray ionization/mass spectrometry. A primary degradation pathway involved cleavage of the ester bond and ring-opening of benzofuran in Sal B was proposed. The complete degradation pathway of Sal B was also proposed. Results showed that ultrasonic irradiation leads to degradation of Sal B in aqueous solution. PMID:27442887

  7. The effect of fatty acid surfactants on the uptake of ozone to aqueous halogenide particles

    Directory of Open Access Journals (Sweden)

    A. Rouvière

    2010-06-01

    Full Text Available The reactive uptake of ozone to deliquesced potassium iodide aerosol particles coated with linear saturated fatty acids (C9, C12, C15, C18 and C20 as surfactants was studied. The experiments were performed in an aerosol flow tube at 293 K and atmospheric pressure. The uptake coefficient on pure deliquesced KI aerosol was γ=(1.10±0.20×10−2 at 72–75% relative humidity. In presence of organic coatings, the uptake coefficient decreased significantly for long straight chain surfactants (>C15, while it was only slightly reduced for the short ones (C9, C12. We linked the kinetic results to the monolayer properties of the surfactants, and specifically to the phase state of the monolayer formed (liquid expanded or liquid condensed state. We also investigated the effect of organic films to mixed deliquesced aerosol composed of a variable mixture of KI and NaCl, which allowed determining the resistance exerted to O3 at the aqueous surface by the two longer chained surfactants pentadecanoic acid (C15 and stearic acid (C18. Finally, the effect of two-component coatings, consisting of a mixture of long and short chained surfactants, was also studied.

  8. Density and activity of perrhenic acid aqueous solutions at T = 298.15 K

    International Nuclear Information System (INIS)

    Highlights: • Water activity and osmolality measurements on highly concentrated perrhenic acid binary solutions have been carried out. • The study led to a new expression of the stoichiometric activity coefficient γ±vs. m. • The parameters of the two most frequently referenced Pitzer and specific interaction theory models have been determined. • The partial molar volume has been calculated. • The density law of the binary solution as a function of its concentration has been determined. - Abstract: Published isopiestic molalities for aqueous HReO4 solutions at T = 298.15 K are completed. Binary data (variation of the osmotic coefficient and activity coefficient of the electrolyte in solution in the water) at T = 298.15 K for perrhenic acid HReO4 are determined by direct water activity and osmolality measurements. The variation of the osmotic coefficient of this acid in water is represented mathematically according to a model recommended by the National Institute of Standards and Technology and according to the specific interaction theory. The data are also used to evaluate the parameters of the standard three-parameters of Pitzer’s ion-interaction model, along with the parameters of Archer’s four-parameter extended ion-interaction model, to higher molalities than previously advised. Experimental thermodynamic data are well represented by these models. Density variations at T = 298.15 K are also established and used to express the activity coefficient values on both the molar and molal concentration scales

  9. Process optimization of reaction of acid leaching residue of asbestos tailing and sodium hydroxide aqueous solution

    Institute of Scientific and Technical Information of China (English)

    DU GaoXiang; ZHENG ShuiLin; DING Hao

    2009-01-01

    Silica is the major component of the acid leaching residue of asbestos tailing. The waterglass solution can be prepared by the reaction of the residue with sodium hydroxide aqueous solution. Compared to the high temperature reaction method, this process is environmental friendly and low cost. In this paper, the reaction process of the residue and the sodium hydroxide aqueous solution is optimized. The op-timum reaction process parameters are as follows: the usage of sodium hydroxide is 26.4 g/100 g acid leaching residue, the reaction temperature is 90℃, the reaction time is 1 h, and the ratio of the liq-uid/solid is 2.0. The significance sequence of the process parameters to the alkali leaching reaction effect is the usage of sodium hydroxide > the ratio of the liquid/solid > the reaction time > the reaction temperature. The significance sequence to the leaching ratio of SiO2 is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. The significance sequence to the modulus of the sodium silicate is the ratio of the liquid/solid > the usage of sodium hydroxide > the reaction time > the reaction temperature. Under the optimum conditions, the leaching ratio of the SiO2 is 77.5%, and the modulus of the sodium silicate is 3.15. The XRD analysis result indicates that the major components of the alkali leaching residue are serpentine, talc, quartz and some albite.

  10. Chemistry in the Venus clouds: Sulfuric acid reactions and freezing behavior of aqueous liquid droplets

    Science.gov (United States)

    Delitsky, M. L.; Baines, K. H.

    2015-11-01

    Venus has a thick cloud deck at 40-70 km altitude consisting of liquid droplets and solid particles surrounded by atmospheric gases. The liquid droplets are highly concentrated aqueous solutions of sulfuric acid ranging in concentration from 70-99 wt%. Weight percent drops off with altitude (Imamura and Hashimoto 2001). There will be uptake of atmospheric gases into the droplet solutions and the ratios of gas-phase to liquid-phase species will depend on the Henry’s Law constant for those solutions. Reactions of sulfuric acid with these gases will form products with differing solubilities. For example, uptake of HCl by H2SO4/H2O droplets yields chlorosulfonic acid, ClSO3H (Robinson et al 1998) in solution. This may eventually decompose to thionyl- or sulfuryl chlorides, which have UV absorbances. HF will also uptake, creating fluorosulfonic acid, FSO3H, which has a greater solubility than the chloro- acid. As uptake continues, there will be many dissolved species in the cloudwaters. Baines and Delitsky (2013) showed that uptake will have a maximum at ~62 km and this is very close to the reported altitude for the mystery UV absorber in the Venus atmosphere. In addition, at very strong concentrations in lower altitude clouds, sulfuric acid will form hydrates such as H2SO4.H2O and H2SO4.4H2O which will have very different freezing behavior than sulfuric acid, with much higher freezing temperatures (Carslaw et al, 1997). Using temperature data from Venus Express from Tellmann et al (2009), and changes in H2SO4 concentrations as a function of altitude (James et al 1997), we calculate that freezing out of sulfuric acid hydrates can be significant down to as low as 56 km altitude. As a result, balloons, aircraft or other probes in the Venus atmosphere may be limited to flying below certain altitudes. Any craft flying at altitudes above ~55 km may suffer icing on the wings, propellers, balloons and instruments which could cause possible detrimental effects (thermal

  11. Calcium isotope fractionation in liquid chromatography with benzo-18-crown-6 resin in aqueous hydrobromic acid medium

    International Nuclear Information System (INIS)

    Liquid chromatography operated in a breakthrough mode was employed to study calcium isotope fractionation in the aqueous hydrobromic acid medium. Highly porous silica beads, the inner pores of which were embedded with a benzo-18-crown-6 ether resin, were used as column packing material. Enrichment of heavier isotopes of calcium was observed in the frontal part of respective calcium chromatograms. The values of the isotope fractionation coefficient were on the order of 10-3. The observed isotope fractionation coefficient was dependent on the concentration of hydrobromic acid in the calcium feed solution; a higher HBr concentration resulted in a smaller fractionation coefficient value. The present calcium isotope effects were most probably mass-dependent, indicating that they mostly came from isotope effects based on molecular vibration. Molecular orbital calculations supported the present experimental results in a qualitative fashion. Chromatography operated in aqueous HBr media is a better system of Ca isotope separation than that operated in aqueous HCl media. (author)

  12. 油酸包覆的机油基Fe3 O4磁流体的制备及表征%Preparation and Characterization of Fe3 O4 Engine oil-based Magnetic Fluid Enveloped by Oleic Acid

    Institute of Scientific and Technical Information of China (English)

    洪勇; 史红兵; 刘杰; 张俊斌; 何美清; 吴奇兵

    2015-01-01

    In this article,the superparamagnetic Fe3 O4 nano - particles were prepared with chemical co - precipitation method firstly,and than oleic acid was enveloped after cleaning the particles;then stabilized engine oil-based magnetic fluid was obtained. The products were characterized with XRD,TEM,VSM,IR and TGA. The mechanism of surfactants that modified Fe3 O4 magnetic particles were discussed. The studies have shown that magnetic fluid has good dispersion and stability,the saturation magnetization of the pure Fe3 O4 particles and the particles coated with oleic acid are 79. 886emu/g and 73. 991emu/g respectively,coating process leads the saturation magnetization to decrease.%首先利用化学共沉淀法制备了具有超顺磁性的纳米Fe3 O4颗粒,然后用油酸对其进行包覆,得到稳定的Fe3 O4机油基磁流体。分别用XRD、IR、TEM、VSM和TGA对所制备的产物进行表征,探讨了油酸包覆Fe3 O4纳米颗粒的形成机理。研究表明,所得磁流体具有高的饱和磁化强度和稳定性,制备的纳米Fe3 O4颗粒的饱和磁化强度为79.886emu/g,用油酸包覆后的颗粒的饱和磁化强度达到73.991emu/g,油酸的包覆使得Fe3 O4颗粒的饱和磁化强度有所降低。

  13. Thermodynamic characteristics of the interaction between nicotinic acid and phenylalanine in an aqueous buffer solution at 298 K

    Science.gov (United States)

    Badelin, V. G.; Tyunina, E. Yu.; Mezhevoi, I. N.; Tarasova, G. N.

    2013-08-01

    The interaction between L-phenylalanine and nicotinic acid is studied by solution calorimetry in an aqueous buffer solution (pH 7.35) at different ratios of the reagents. Experimental data on the enthalpy of dissolution of amino acid in the buffer solution of nicotinic acid at 298.15 K are calculated. The values of thermodynamic parameters for the complexation of L-phenylalanine with nicotinic acid are calculated. It is shown that the formation of a 1: 2 molecular complex is stabilized by the entropy factor due to the dominant role of the dehydration effect of initial reagents.

  14. A GREEN CHEMISTRY APPROACH TO PREPARATION OF CORE (FE OR CU)-SHELL (NOBLE METALS) NANOCOMPOSITES USING AQUEOUS ASCORBIC ACID

    Science.gov (United States)

    A greener method to fabricate novel core (Fe or Cu)-shell (noble metals) nanocomposites of transition metals such as Fe and Cu and noble metals such as Au, Pt, Pd, and Ag using aqueous ascorbic acid is described. Transition metal salts such as Cu and Fe were reduced using ascor...

  15. Acid dissociation mechanisms of Si(OH)(4) and Al(H2O)(6)(3+) in aqueous solution

    NARCIS (Netherlands)

    X. Liu; X. Lu; E.J. Meijer; R. Wang; H. Zhou

    2010-01-01

    Silicic acid and the hexa-aqua of Al3+ are fundamental model aqueous species of chemical importance in nature. In order to investigate their hydroxyl dissociation mechanisms, Car-Parrinello molecular dynamics (CPMD) simulations were carried out, which allow treating the solutes and solvents on the s

  16. A chemiluminescence-based continuous flow aqueous ozone analyzer using photoactivated chromotropic acid.

    Science.gov (United States)

    Takayanagi, Toshio; Dasgupta, Purnendu K

    2005-05-15

    Ozone has become the oxidant of choice for water disinfection, especially in large water treatment facilities. This paper describes a fast and sensitive method for the determination of ozone content by reaction with photoactivated chromotropic acid (CA, 4,5-dihydroxynaphthalene-2,7-disulfonic acid), which results in intense chemiluminescence (CL). Freshly ozonated water from a recirculating ozonizer/reservoir is injected into a carrier stream of deionized water in the flow-injection mode. This flow mixes with a stream of photoactivated CA solution in a spiral cell placed directly on top of an inexpensive miniature (8mm diameter active area) photomultiplier tube (PMT). Alkaline CA is photoactivated by passing it through a FEP-Teflon((R)) coil (residence time approximately 50s) wrapped around a 1W UV lamp emitting at 254nm; without photoactivation, the signal is approximately 70-fold lower. The S/N=3 limit of detection for aqueous ozone is 3mugl(-1) and good response slope is obtained up to an ozone concentration of 1.4mgl(-1), the highest that could be made in this study. The response obeyed a quadratic equation with r(2)=0.9984. No interference from permanganate ion is observed. The proposed system was applied to the monitoring of ozonation status of a playa lake water that exhibited significant ozone demand.

  17. Kinetics of Acid Blue 1 Adsorption from Aqueous Solution by Carbonaceous Substrate Produced from Biotic Precursor

    Institute of Scientific and Technical Information of China (English)

    FAZLULLAH,Khan Bangash; SULTAN,Alam; IRSHAD,Ahmad

    2007-01-01

    Adsorption of acid blue 1 from aqueous solution onto carbonaceous substrate produced from the wood of Paulownia tomentosa was investigated. The samples characterized by FTIR, SEM, EDS and XRD techniques, indicated that the surface functional groups like carboxyl, lactones or phenols and ethers have disappeared at high activation temperature (800 ℃) and as a result porous structure was developed that has a positive effect on the adsorption capacity. Bangham and parabolic diffusion models were applied to the kinetic adsorption data, which show that the adsorption of acid blue 1 was a diffusion controlled process. The reaction rate increased with the increase in temperatures of both the adsorption and activation. Thermodynamic parameters like △E≠, △H≠, △S≠ and △G≠ were calculated from the kinetic data. The negative values of △S≠ reflected the decrease in the disorder of the system at the solid-solution interface during adsorption. Gibbs free energy (△G≠), representing the driving force for the affinity of dye for the carbon surface, increased with the increase in sample activation and the adsorption temperatures.

  18. Oxidation of hydrogen peroxide by [NiIII(cyclam)]3+ in aqueous acidic media

    Indian Academy of Sciences (India)

    Sankaran Anuradha; Venkatapuram Ramanujam Vijayaraghavan

    2013-09-01

    The kinetics of oxidation of H2O2 by [NiIII(cyclam)]3+, [NiIIIL1], was studied in aqueous acidic media at 25°C and I = 0.5M (NaClO4). The [NiIIIL1] to [NiIIL1] reduction was found to be fast in the presence of Cu(II) ion than the oxidation of the cyclam ligand by ·OH. The rate constant showed an inverse acid dependence on H+ ion at the pH range 1-1.5. The presence of sulphate retards the reaction. Macrocylic ligand oxidation was followed spectrophotometrically by examining the oxidation of nickel(II) complexes of macrocyclic ligands such as 1,8-bis(2-hydroxyethyl)-1,3,6,8,10,13-hexaazacyclotetradecane (L2), -5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L3), rac-Me6[14]-4,11-dieneN4 (L4) by reaction with hydrogen peroxide. The rate constant for the cross reaction is discussed in terms of Marcus relationship.

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

    Directory of Open Access Journals (Sweden)

    Yao Shuhua

    2012-12-01

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

  20. Biosorption of Methyl Blue Onto Tartaric Acid Modified Wheat Bran From Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Shuhua Yao

    2012-12-01

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

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

    Science.gov (United States)

    Yao, Shuhua; Lai, Hong; Shi, Zhongliang

    2012-01-01

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

  2. Ascorbic Acid Content in Extractive Aqueous Solutions of Rosa canina L. Fruits

    Directory of Open Access Journals (Sweden)

    Veturia-Ileana Nueleanu

    2008-03-01

    Full Text Available The main goal of the hereby study is two folded: first, to mark out the most adequate methods of preparing the watery solution extracts (infusions, decoctions in order to obtain a high content of ascorbic acid, and second, to identify the most suitable method for determining this vitamin in aqueous solution extracts made out of medicinal herbs. In this experiment six groups were assembled containing 20 fruit samples each. The samples were analyzed one week, one and a half month and three months, respectively, after gathering. Fruit drying was accomplished either in open air, at room temperature, or artificially, for three days, in 15 minutes intervals at 95°C (in the exicator, followed again by room temperature drying. Preparation of each group was different: it comprised either pickling in cold water for 10 hours, followed by sinking in cold water, boiling and then cooling, or sinking the fruits in boiling water followed by cooling, or sinking the fruits in boiling water followed by boiling the solution for five or 10 minutes, or, finally, by infusion and decoction method. The results obtained through the Tillmans method revealed a high level of ascorbic acid when the fruits were immersed into boiling water (100°C and boiled in open fire (11.02 ± 1.51 mg % for five minutes or when they were introduced in boiling water and kept covered in the boiling basin for 30 minutes (12.26 ± 0.55mg %.

  3. Sodium phthalamates as corrosion inhibitors for carbon steel in aqueous hydrochloric acid solution

    International Nuclear Information System (INIS)

    Highlights: → N-Alkyl-sodium phthalamates as corrosion inhibitors for industry in acidic medium. → Compounds behaved as mixed type inhibitors and followed Langmuir adsorption isotherm. → Efficiencies were proportional to aliphatic chain length and inhibitor concentration. → Iron complexes and chelates with phthalamates contributed to carbon steel protection. - Abstract: Three compounds of N-alkyl-sodium phthalamates were synthesized and tested as corrosion inhibitors for carbon steel in 0.5 M aqueous hydrochloric acid. Tests showed that inhibitor efficiencies were related to aliphatic chain length and dependent on concentration. N-1-n-tetradecyl-sodium phthalamate displayed moderate efficiency against uniform corrosion, 42-86% at 25 deg. C and 25-60% at 40 oC. Tests indicated that compounds behave as mixed type inhibitors where molecular adsorption on steel followed Langmuir isotherm, whereas thermodynamic suggested that a physisorption process occurred. XPS analysis confirmed film formation on surface, where Fe+2 complexes and Fe+2 chelates with phthalamates prevented steel from further corrosion.

  4. Adsorption of Acid Red 57 from aqueous solutions onto polyacrylonitrile/activated carbon composite.

    Science.gov (United States)

    El-Bindary, Ashraf A; Diab, Mostafa A; Hussien, Mostafa A; El-Sonbati, Adel Z; Eessa, Ahmed M

    2014-04-24

    The adsorption of Acid Red 57 (AR57) onto Polyacrylonitrile/activated carbon (PAN/AC) composite was investigated in aqueous solution in a batch system with respect to contact time, pH and temperature. Physical characteristics of (PAN/AC) composite such as fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) were obtained. Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were determined. The activation energy of adsorption was also evaluated for the adsorption of AR57 onto (PAN/AC) composite. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data. The dynamic data fitted the pseudo-second-order kinetic model well. The activation energy, change of free energy, enthalpy and entropy of adsorption were also evaluated for the adsorption of AR57 onto (PAN/AC) composite. The thermodynamics of the adsorption indicated spontaneous and exothermic nature of the process. The results indicate that (PAN/AC) composite could be employed as low-cost material for the removal of acid dyes from textile effluents. PMID:24463242

  5. Removal of aqueous perfluorooctanoic acid (PFOA) using starch-stabilized magnetite nanoparticles.

    Science.gov (United States)

    Gong, Yanyan; Wang, Lin; Liu, Juncheng; Tang, Jingchun; Zhao, Dongye

    2016-08-15

    Fully stabilized magnetite (Fe3O4) nanoparticles were prepared with a water-soluble starch as a stabilizer and tested for removal of aqueous perfluorooctanoic acid (PFOA). The presence of starch at ≥0.2wt% can fully stabilize 0.1g/L as Fe of the Fe3O4 nanoparticles. The particle stabilization technique resulted in 2.4 times higher PFOA uptake. Fourier transform infrared spectra suggested that the main PFOA removal mechanism was inner-sphere complexation. Batch kinetic experiments revealed that the starch-stabilized nanoparticles facilitated a rapid PFOA uptake with a sorption equilibrium time of 30min, and the sorption process followed a pseudo-second-order kinetic model. The Langmuir model was able to well interpret the adsorption isotherm, with a maximum adsorption capacity of 62.5mg/g. Increasing pH from 4.7 to 9.6 led to a sharp increase (by 2.6 times) in PFOA uptake. The presence of 12mg/L humic acid inhibited PFOA uptake by 96%, while effect of ionic strength (CaCl2=0-2mmol/L) was negligible. The nanoparticles significantly reduced the biological toxicity of PFOA. The results demonstrated promise of starch-stabilized Fe3O4 nanoparticles as a "green" adsorbent for effective removal of PFOA in soil and groundwater. PMID:27100000

  6. A systematic review of high-oleic vegetable oil substitutions for other fats and oils on cardiovascular disease risk factors: implications for novel high-oleic soybean oils.

    Science.gov (United States)

    Huth, Peter J; Fulgoni, Victor L; Larson, Brian T

    2015-11-01

    High-oleic acid soybean oil (H-OSBO) is a trait-enhanced vegetable oil containing >70% oleic acid. Developed as an alternative for trans-FA (TFA)-containing vegetable oils, H-OSBO is predicted to replace large amounts of soybean oil in the US diet. However, there is little evidence concerning the effects of H-OSBO on coronary heart disease (CHD)(6) risk factors and CHD risk. We examined and quantified the effects of substituting high-oleic acid (HO) oils for fats and oils rich in saturated FAs (SFAs), TFAs, or n-6 (ω-6) polyunsaturated FAs (PUFAs) on blood lipids in controlled clinical trials. Searches of online databases through June 2014 were used to select studies that defined subject characteristics; described control and intervention diets; substituted HO oils compositionally similar to H-OSBO (i.e., ≥70% oleic acid) for equivalent amounts of oils high in SFAs, TFAs, or n-6 PUFAs for ≥3 wk; and reported changes in blood lipids. Studies that replaced saturated fats or oils with HO oils showed significant reductions in total cholesterol (TC), LDL cholesterol, and apolipoprotein B (apoB) (P oil sources with HO oils showed significant reductions in TC, LDL cholesterol, apoB, TGs, TC:HDL cholesterol and increased HDL cholesterol and apoA-1 (mean percentage of change: -5.7%, -9.2%, -7.3%, -11.7%, -12.1%, 5.6%, 3.7%, respectively; P oils high in n-6 PUFAs with equivalent amounts of HO oils, TC, LDL cholesterol, TGs, HDL cholesterol, apoA-1, and TC:HDL cholesterol did not change. These findings suggest that replacing fats and oils high in SFAs or TFAs with either H-OSBO or oils high in n-6 PUFAs would have favorable and comparable effects on plasma lipid risk factors and overall CHD risk.

  7. CT在油酸致兔急性呼吸窘迫综合征早期诊断中的应用%The value of computed tomography in early diagnosis in rabbits with acute respiratory distress syndrome induced by oleic acid

    Institute of Scientific and Technical Information of China (English)

    金兆辰; 蒋文芳; 吉木森; 姚利群; 虞志新; 冯玉玲; 吴永红; 周红

    2010-01-01

    Objective To investigate the clinical value of computed tomography(CT)in early diagnosis by comparison of the changes of different defrees of aeratation in lung compartments of rabbits with acute respiratory distress syndrome(ARDS)induced by oleic acid.Method Twenty white rabbits were randomly(random number)divided into control group and oleic acid group.Oleic acid(0.1 mL/kg)was given intravenously to induce ARDS in cr room.Arterial blood gas analysis was determined every 15 rain.All rabbits underwent chest X-my and lung spiral cr scans examinations at basal state(T_0),200 mmHg<OI<300 mmHg(T_1)and OI<200 mmHg(T_2).The percentages of different degrees aeratation in different aerated lung compartments were measured by CT software at the same time.Changes in different lung compartments,chest images,and the correlation between lung volume and OI were investigated.Moreover,the wet/dry ratio and pathological changes in lung were examined.Data were evaluated by two-sample t-test and repeated measutement data analysis of variance,and Spearman raak correlation was used to analyze the correlation between two variables.Results(1)The percentages of non-aerated,poorly aerated and normally aerated compartment were significantly different at different intervals in the oleic add group (P<0.01),and the percentages of non-aerated compartment were(19.30±2.34)%at T_1 and)26.47±1.89)%at T_2,and those of the poorly aerted compartment were(28.08±2.70)%at T_1 and(37.40±1.78)%at T_2 which were higber than those in control group(P<0.01).While the percentages of normally aerated compartment were(47.38±3.19)%at T_1 and(30.82±3.25)%at T_2 which were lower than those in control group [(79.12±1.25)%at T_1 and(78.23±1.84)%at T_2](P<0.01),there were no significant differences in percentages of hyperinflated compartment between two groups(P>0.05).(2)There was a negative correlation in respect of OI between non-aerated and poorly aerated compartments(-0.745~-0.636)while the

  8. Photochemical oxidation of chloride ion by ozone in acid aqueous solution.

    Science.gov (United States)

    Levanov, Alexander V; Isaykina, Oksana Ya; Amirova, Nazrin K; Antipenko, Ewald E; Lunin, Valerii V

    2015-11-01

    The experimental investigation of chloride ion oxidation under the action of ozone and ultraviolet radiation with wavelength 254 nm in the bulk of acid aqueous solution at pH 0-2 has been performed. Processes of chloride oxidation in these conditions are the same as the chemical reactions in the system O3 - OH - Cl(-)(aq). Despite its importance in the environment and for ozone-based water treatment, this reaction system has not been previously investigated in the bulk solution. The end products are chlorate ion ClO3(-) and molecular chlorine Cl2. The ions of trivalent iron have been shown to be catalysts of Cl(-) oxidation. The dependencies of the products formation rates on the concentrations of O3 and H(+) have been studied. The chemical mechanism of Cl(-) oxidation and Cl2 emission and ClO3(-) formation has been proposed. According to the mechanism, the dominant primary process of chloride oxidation represents the complex interaction with hydroxyl radical OH with the formation of Cl2(-) anion-radical intermediate. OH radical is generated on ozone photolysis in aqueous solution. The key subsequent processes are the reactions Cl2(-) + O3 → ClO + O2 + Cl(-) and ClO + H2O2 → HOCl + HO2. Until the present time, they have not been taken into consideration on mechanistic description and modelling of Cl(-) oxidation. The final products are formed via the reactions 2ClO → Cl2O2, Cl2O2 + H2O → 2H(+) + Cl(-) + ClO3(-) and HOCl + H(+) + Cl(-) ⇄ H2O + Cl2. Some portion of chloride is oxidized directly by O3 molecule with the formation of molecular chlorine in the end.

  9. Poorly crystalline hydroxyapatite: A novel adsorbent for enhanced fulvic acid removal from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wei [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China); Yang, Lei; Zhong, Wenhui; Cui, Jing [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Wei, Zhenggui, E-mail: weizhenggui@gmail.com [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China)

    2015-03-30

    Graphical abstract: - Highlights: • Poorly crystalline HAP was firstly used for FA removal from aqueous solution. • The maximum adsorption capacity was determined to be 90.20 mg/g at 318 K. • Adsorption kinetics, isotherms and thermodynamic have been studied in detail. • Adsorption mechanism involved surface complexation, electrostatic interaction and hydrogen bonding. - Abstract: In this study, poorly crystalline hydroxyapatite (HAP) was developed as an efficient adsorbent for the removal of fulvic acid (FA) from aqueous solution. Surface functionality, crystallinity, and morphology of the synthetic adsorbent were studied by Fourier-transformation infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of various parameters such as crystallinity of adsorbent, contact time, adsorbent dosage, pH, initial adsorbate concentration, temperature, ionic strength and the presence of alkaline earth metal ions on FA adsorption were investigated. Results indicated that the nanosized HAP calcined at lower temperature was poorly crystalline (X{sub c} = 0.23) and had better adsorption capacity for FA than those (X{sub c} = 0.52, 0.86) calcined at higher temperature. FA removal was increased with increases of adsorbent dosage, temperature, ionic strength and the presence of alkali earth metal ions, but decreased as the pH increased. Kinetic studies showed that pseudo-second-order kinetic model better described the adsorption process. Equilibrium data were best described by Sips models, and the estimated maximum adsorption capacity of poorly crystalline HAP was 90.20 mg/g at 318 K, displaying higher efficiency for FA removal than previously reported adsorbents. FT-IR results revealed that FA adsorption over the adsorbent could be attributed to the surface complexation between the oxygen atom of functional groups of FA and calcium ions of HAP. Regeneration studies indicated that HAP could be recyclable for a long

  10. Improving aqueous solubility and antitumor effects by nanosized gambogic acid-mPEG2000 micelles

    Directory of Open Access Journals (Sweden)

    Cai LL

    2013-12-01

    Full Text Available Lulu Cai,1,* Neng Qiu,2,* Mingli Xiang,3,* Rongsheng Tong,1 Junfeng Yan,1 Lin He,1 Jianyou Shi,1 Tao Chen,4 Jiaolin Wen,3 Wenwen Wang,3 Lijuan Chen31Department of Pharmacy, Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, 2College of Materials and Chemistry and Chemical Engineering, Chengdu University of Technology, 3State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China; 4Faculty of Pharmacy, University of Montreal, Montreal, QC, Canada *These authors contributed equally to this paperAbstract: The clinical application of gambogic acid, a natural component with promising antitumor activity, is limited due to its extremely poor aqueous solubility, short half-life in blood, and severe systemic toxicity. To solve these problems, an amphiphilic polymer-drug conjugate was prepared by attachment of low molecular weight (ie, 2 kDa methoxy poly(ethylene glycol methyl ether (mPEG to gambogic acid (GA-mPEG2000 through an ester linkage and characterized by 1H nuclear magnetic resonance. The GA-mPEG2000 conjugates self-assembled to form nanosized micelles, with mean diameters of less than 50 nm, and a very narrow particle size distribution. The properties of the GA-mPEG2000 micelles, including morphology, stability, molecular modeling, and drug release profile, were evaluated. MTT (3-(4,5-dimethylthiazol-2-yl-2,5 diphenyl tetrazolium bromide tests demonstrated that the GA-mPEG2000 micelle formulation had obvious cytotoxicity to tumor cells and human umbilical vein endothelial cells. Further, GA-mPEG2000 micelles were effective in inhibiting tumor growth and prolonged survival in subcutaneous B16-F10 and C26 tumor models. Our findings suggest that GA-mPEG2000 micelles may have promising applications in tumor therapy.Keywords: gambogic acid, poly(ethylene glycol-drug conjugate, micelle, antitumor, toxicity

  11. Bioreversible Derivatives of Phenol. 2. Reactivity of Carbonate Esters with Fatty Acid-like Structures Towards Hydrolysis in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Claus Larsen

    2007-10-01

    Full Text Available A series of model phenol carbonate ester prodrugs encompassing derivatives with fatty acid-like structures were synthesized and their stability as a function of pH (range 0.4 – 12.5 at 37°C in aqueous buffer solutions investigated. The hydrolysis rates in aqueous solutions differed widely, depending on the selected pro-moieties (alkyl and aryl substituents. The observed reactivity differences could be rationalized by the inductive and steric properties of the substituent groups when taking into account that the mechanism of hydrolysis may change when the type of pro-moiety is altered, e.g. n-alkyl vs. t-butyl. Hydrolysis of the phenolic carbonate ester 2-(phenoxycarbonyloxy-acetic acid was increased due to intramolecular catalysis, as compared to the derivatives synthesized from ω-hydroxy carboxylic acids with longer alkyl chains. The carbonate esters appear to be less reactive towards specific acid and base catalyzed hydrolysis than phenyl acetate. The results underline that it is unrealistic to expect that phenolic carbonate ester prodrugs can be utilized in ready to use aqueous formulations. The stability of the carbonate ester derivatives with fatty acid-like structures, expected to interact with the plasma protein human serum albumin, proved sufficient for further in vitro and in vivo evaluation of the potential of utilizing HSA binding in combination with the prodrug approach for optimization of drug pharmacokinetics.

  12. Changing the Action of Iron from Stoichiometric to Electrocatalytic in the Hydrogenation of Ketones in Aqueous Acidic Media.

    Science.gov (United States)

    Gottardo, Marina; Easton, Max; Fabos, Viktoria; Guo, Si-Xuan; Zhang, Jie; Perosa, Alvise; Selva, Maurizio; Bond, Alan M; Masters, Anthony F; Maschmeyer, Thomas

    2015-11-01

    Cyclohexanone, a model compound chosen to conveniently represent small oxygenates present in the aqueous phase of biomass hydrothermal upgrading streams, was hydrogenated in the presence of electrodeposited iron(0) using aqueous formic or sulfuric acid as a hydrogen donor. Under these conditions, zero-valent iron is consumed stoichiometrically and serves as both a formic acid decomposition site and a hydrogen transfer agent. However, the resulting iron(II) can be used to continuously regenerate iron(0) when a potential is applied to the glassy carbon working electrode. Controlled potential electrolysis experiments show a 17% conversion of cyclohexanone (over 1000 seconds) to cyclohexanol with >80% efficiency of iron deposition from an iron(II) sulfate solution containing formic or sulfuric acid. In the absence of electrodeposited iron, formation of cyclohexanol could not be detected. PMID:26382111

  13. Copper- or manganese-doped ZnS quantum dots as fluorescent probes for detecting folic acid in aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Geszke-Moritz, Malgorzata [Laboratoire Reactions et Genie des Procedes (LRGP), Nancy-University, CNRS, 1 rue Grandville, 54001 Nancy Cedex (France); Department of Pharmaceutical Technology, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan (Poland); Clavier, Gilles [PPSM, ENS Cachan, CNRS, UniverSud, 61 avenue President Wilson, 94230 Cachan (France); Lulek, Janina [Department of Pharmaceutical Technology, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznan (Poland); Schneider, Raphaeel, E-mail: raphael.schneider@ensic.inpl-nancy.fr [Laboratoire Reactions et Genie des Procedes (LRGP), Nancy-University, CNRS, 1 rue Grandville, 54001 Nancy Cedex (France)

    2012-04-15

    3-Mercaptopropionic acid-capped core/shell ZnS:Cu/ZnS and ZnS:Mn/ZnS doped quantum dots (QDs) prepared through hydrothermal methods exhibit high photoluminescence intensity as well as good photostability. These water-dispersible nanoparticles exhibit high fluorescence sensitivity to folic acid due to the high affinity of the carboxylate groups and nitrogen atoms of folic acid towards the Zn surface atoms of the doped dots. Quenching of the fluorescence intensity of the QDs allows the detection of folic acid concentrations as low as 11 {mu}M, thus affording a very sensitive system for the sensing of this biologically active molecule in aqueous solution. The possible quenching mechanism is discussed. - Graphical abstract: A sensitive method for the detection of folic acid based on the fluorescence quenching of Mn- or Cu-doped ZnS quantum dots was developed. Highlights: Black-Right-Pointing-Pointer Quenching of the fluorescence intensity of doped ZnS QDs in the presence of folic acid. Black-Right-Pointing-Pointer New fluorescent sensors for folic acid. Black-Right-Pointing-Pointer Detection of folic acid concentrations as low as 11 {mu}M in aqueous solution. Black-Right-Pointing-Pointer The Perrin model and fluorescence lifetimes of ZnS:Mn QDs demonstrate a static quenching mechanism. Black-Right-Pointing-Pointer Quenching efficiency of ZnS:Cu QDs correlates with the Stern-Volmer model.

  14. Copper- or manganese-doped ZnS quantum dots as fluorescent probes for detecting folic acid in aqueous media

    International Nuclear Information System (INIS)

    3-Mercaptopropionic acid-capped core/shell ZnS:Cu/ZnS and ZnS:Mn/ZnS doped quantum dots (QDs) prepared through hydrothermal methods exhibit high photoluminescence intensity as well as good photostability. These water-dispersible nanoparticles exhibit high fluorescence sensitivity to folic acid due to the high affinity of the carboxylate groups and nitrogen atoms of folic acid towards the Zn surface atoms of the doped dots. Quenching of the fluorescence intensity of the QDs allows the detection of folic acid concentrations as low as 11 μM, thus affording a very sensitive system for the sensing of this biologically active molecule in aqueous solution. The possible quenching mechanism is discussed. - Graphical abstract: A sensitive method for the detection of folic acid based on the fluorescence quenching of Mn- or Cu-doped ZnS quantum dots was developed. Highlights: ► Quenching of the fluorescence intensity of doped ZnS QDs in the presence of folic acid. ► New fluorescent sensors for folic acid. ► Detection of folic acid concentrations as low as 11 μM in aqueous solution. ► The Perrin model and fluorescence lifetimes of ZnS:Mn QDs demonstrate a static quenching mechanism. ► Quenching efficiency of ZnS:Cu QDs correlates with the Stern-Volmer model.

  15. Photocatalytic CO2 reduction to formic acid using a Ru(II)-Re(I) supramolecular complex in an aqueous solution.

    Science.gov (United States)

    Nakada, Akinobu; Koike, Kazuhide; Nakashima, Takuya; Morimoto, Tatsuki; Ishitani, Osamu

    2015-02-16

    In an aqueous solution, photophysical, photochemical, and photocatalytic abilities of a Ru(II)-Re(I) binuclear complex (RuReCl), of which Ru(II) photosensitizer and Re(I) catalyst units were connected with a bridging ligand, have been investigated in details. RuReCl could photocatalyze CO2 reduction using ascorbate as an electron donor, even in an aqueous solution. The main product of the photocatalytic reaction was formic acid in the aqueous solution; this is very different in product distribution from that in a dimethylformamide (DMF) and triethanolamine (TEOA) mixed solution in which the main product was CO. A (13)CO2 labeling experiment clearly showed that formic acid was produced from CO2. The turnover number and selectivity of the formic acid production were 25 and 83%, respectively. The quantum yield of the formic acid formation was 0.2%, which was much lower, compared to that in the DMF-TEOA mixed solution. Detail studies of the photochemical electron-transfer process showed back-electron transfer from the one-electron-reduced species (OERS) of the photosensitizer unit to an oxidized ascorbate efficiently proceeded, and this should be one of the main reasons why the photocatalytic efficiency was lower in the aqueous solution. In the aqueous solution, ligand substitution of the Ru(II) photosensitizer unit proceeded during the photocatalytic reaction, which was a main deactivation process of the photocatalytic reaction. The product of the ligand substitution was a Ru(II) bisdiimine complex or complexes with ascorbate as a ligand or ligands. PMID:25654586

  16. Lewis Acid Pairs for the Activation of Biomass-derived Oxygenates in Aqueous Media

    Energy Technology Data Exchange (ETDEWEB)

    Roman, Yuriy [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2015-09-14

    The objective of this project is to understand the mechanistic aspects behind the cooperative activation of oxygenates by catalytic pairs in aqueous media. Specifically, we will investigate how the reactivity of a solid Lewis acid can be modulated by pairing the active site with other catalytic sites at the molecular level, with the ultimate goal of enhancing activation of targeted functional groups. Although unusual catalytic properties have been attributed to the cooperative effects promoted by such catalytic pairs, virtually no studies exist detailing the use heterogeneous water-tolerant Lewis pairs. A main goal of this work is to devise rational pathways for the synthesis of porous heterogeneous catalysts featuring isolated Lewis pairs that are active in the transformation of biomass-derived oxygenates in the presence of bulk water. Achieving this technical goal will require closely linking advanced synthesis techniques; detailed kinetic and mechanistic investigations; strict thermodynamic arguments; and comprehensive characterization studies of both materials and reaction intermediates. For the last performance period (2014-2015), two technical aims were pursued: 1) C-C coupling using Lewis acid and base pairs in Lewis acidic zeolites. Tin-, zirconium-, and hafnium containing zeolites (e.g., Sn-, Zr-, and Hf-Beta) are versatile solid Lewis acids that selectively activate carbonyl functional groups. In this aim, we demonstrate that these zeolites catalyze the cross-aldol condensation of aromatic aldehydes with acetone under mild reaction conditions with near quantitative yields. NMR studies with isotopically labeled molecules confirm that acid-base pairs in the Si-O-M framework ensemble promote soft enolization through α-proton abstraction. The Lewis acidic zeolites maintain activity in the presence of water and, unlike traditional base catalysts, in acidic solutions. 2) One-pot synthesis of MWW zeolite nanosheets for activation of bulky substrates. Through

  17. Optimization and orthogonal design of an ultrasonic-assisted aqueous extraction process for extracting chlorogenic acid from dry tobacco leaves

    Institute of Scientific and Technical Information of China (English)

    Martin Tongai Mazvimba; YU Ying; CUI Zhi-Qin; ZHANG Ying

    2012-01-01

    Processing parameters for heat reflux and ultrasonic-assisted extraction techniques were optimized.Optimal operating conditions,extraction solvents and extraction yields for both methods were established.Although methanol showed high extraction efficiency in heat reflux extraction,residual amounts of methanol caused adulteration of extracts.To circumvent this drawback,a novel ultrasonic-assisted aqueous extraction process was optimized and orthogonally designed to pave the way for replacing the toxic organic solvent,methanol with water.A new approach which utilizes fractional volumes of an extraction solvent was developed to minimize solvent consumption,improve chlorogenic acid solubility in water and enhance its aqueous extraction from dried tobacco leaves.Desired trajectories for the new ultrasonic assisted aqueous extraction process were found.

  18. Enhanced ozonation of dichloroacetic acid in aqueous solution using nanometer ZnO powders

    Institute of Scientific and Technical Information of China (English)

    Xu Zhai; Zhonglin Chen; Shuqing Zhao; He Wang; Lei Yang

    2010-01-01

    Nanometer zinc oxide (ZnO) powders were used as a catalyst to enhance the ozonation for the degradation of dichloroacetic acid (DCAA) in aqueous solution.The batch experiments were carried out to investigate the effects of key factors such as catalyst dosage,ozone dosage,solution pH and ten-butyl alcohol (t-BuOH) on the degradation efficiency of DCAA.Density functional theory (DFT) and ozonation processes were not effective for DCAA removal,and the addition of ZnO catalyst improved the degradation efficiency of DCAA during ozonation,which caused an increase of 22.8% for DCAA decomposition compared to the case of ozonation alone after 25 min.Under the same experimental conditions,the DCAA decomposition was enhanced by increasing catalyst dosage from 100 to 500 mg/L and ozone dosage from 0.83 to 3.2 mg/L,The catalytic ozonation process is more pronounced than the ozonation process alone at pH 3.93,6.88,and 10.With increasing the concentration of t-BuOH from 10 to 200 mg/L,the degradation of DCAA was significantly molecule ozone followed by the interaction of adsorbed ozone with active sites of the catalyst surface.It is also concluded that ZnO of ozone.

  19. Physicochemical Properties of Amino Acids in Aqueous Caffeine Solution at 25, 30, 35 and 40 ℃

    Institute of Scientific and Technical Information of China (English)

    ALI A.; SABIR S.; SHAHJAHAN; HYDER S.

    2006-01-01

    Density, viscosity, and refractive index, for glycine, DL-alanine, L-serine and DL-valine have been determined in aqueous solution of 0.05 mol/kg caffeine as a function of amino acid (AA) concentration at 25, 30, 35, and 40 ℃.The density data have been used to compute apparent molar volume. The partial molar volume (limiting apparent molar volume) was obtained by applying the Masson's equation. The viscosity data have been analyzed by means of Jones-Dole equation. The values of Falkenhagen coefficient and Jones-Dole coefficient thus obtained are used to interpret the solute-solute and solute-solvent interactions, respectively. Hydration number was also computed. The transition-state theory was applied to obtain the activation parameters of viscous flow, I.e., free energy of activation per mole of solvent, and solute. The enthalpy and entropy of activation of viscous flow were computed for the system. Refractive index was used to calculate molar refractivity of the mixtures. The results have been interpreted in the lightof various interactions occurring between the components of the mixtures under applied experimental conditions.

  20. Photodecomposition of tetrabromobisphenol A in aqueous humic acid suspension by irradiation with light of various wavelengths.

    Science.gov (United States)

    Han, Sang Kuk; Yamasaki, Toshihide; Yamada, Ken-ichi

    2016-03-01

    The reactive species generated in aqueous 3,3',5,5'-tetrabromobisphenol A (TBBPA)/humic acid (HA) suspensions above the TBBPA pKa (∼7.4), under various light-irradiation conditions, namely ambient and ultraviolet light, were investigated using electron paramagnetic resonance (EPR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). We confirmed that singlet oxygen and OH radicals are the key reactive oxygen species generated at wavelengths greater than 400 and 300 nm, respectively. The amount of 2,6-dibromo-p-benzosemiquinone anion radicals (2,6-DBSQ(•-)) formed under irradiation at 400 nm increased linearly with respect to irradiation time; the initial reaction rate was 7.03 × 10(-9) mol g(-1) HA s(-1). The rate increased with increasing pH and light intensity. LC-MS and EPR spectroscopy showed that tribromohydroxybisphenol A was formed under irradiation at 300 nm via reaction of OH radicals with TBBPA. This study, for the first time, shows that the main byproducts formed during irradiation at wavelengths above 300 nm are 2,6-DBSQ(•-) and tribromohydroxybisphenol A, generated from singlet oxygen ((1)O2) and OH radicals, respectively. Photodecomposition of TBBPA in the environment may occur by formation of (1)O2 and OH radicals.

  1. Kinetic Modelling for Flavonoid Recovery from Red Grape (Vitis vinifera Pomace with Aqueous Lactic Acid

    Directory of Open Access Journals (Sweden)

    Katerina Tzima

    2014-12-01

    Full Text Available This study was undertaken with the aim of establishing a correlation between the extraction yield in total flavonoids from red grape pomace and the extraction temperature, using 0.5% (w/v aqueous lactic acid as the solvent system. Extraction of flavonoids was found to obey second-order kinetics, and on such a basis, the yield in total flavonoids at saturation could be very effectively determined and correlated with temperature using non-linear regression. The results indicated that the extraction yield at saturation is highly correlated with temperature, following a quadratic function. The extract obtained at 40 °C had an optimal predicted total flavonoid yield of 13.27 mg rutin equivalents per gram of dry weight, and it was further analyzed by liquid chromatography-mass spectrometry to characterize its major constituents. The polyphenols detected were flavanols, flavonols and an anthocyanin. The outcome of this study outlined that temperatures above 40 °C are rather unfavorable for flavonoid extraction from red grape pomace, as suggested by the model established through kinetics.

  2. Removal of acid blue 062 on aqueous solution using calcinated colemanite ore waste

    International Nuclear Information System (INIS)

    Colemanite ore waste (CW) has been employed as adsorbent for the removal of acid blue 062 anionic dye (AB 062) from aqueous solution. The adsorption of AB 062 onto CW was examined with respect to contact time, calcination temperature, particle size, pH, adsorbent dosage and temperature. The physical and chemical properties of the CW, such as particle sizes and calcinations temperature, play important roles in dye adsorption. The dye adsorption largely depends on the initial pH of the solution with maximum uptake occurring at pH 1.Three simplified kinetics models, namely, pseudo-first order, pseudo-second order, and intraparticle diffusion models were tested to investigate the adsorption mechanisms. The kinetic adsorption of AB 062 on CW follows a pseudo-second order equation. The adsorption data have been analyzed using Langmuir and Freundlich isotherms. The results indicate that the Langmuir model provides the best correlation of the experimental data. Isotherms have also been used to obtain the thermodynamic parameters such as free energy, enthalpy and entropy of the adsorption of dye onto CW

  3. Preparation and characterization of aqueous dispersions of high amylose starch and conjugated linoleic acid complex.

    Science.gov (United States)

    Seo, Tae-Rang; Kim, Hee-Young; Lim, Seung-Taik

    2016-11-15

    Crystalline starch-CLA complexes were prepared by blending an alcoholic solution of conjugated linoleic acid (CLA) in an aqueous high-amylose maize starch dispersion. Recovery yield of CLA in the precipitates obtained by centrifuging the dispersion was dependent on reaction conditions such as temperature, time and pH. The CLA recovery reached a maximum when the reaction was performed at 90°C for 6h at neutral pH, with 67.7% of the initial CLA being co-precipitated with starch. The precipitates contained amylose-CLA complex exhibiting a V6I-type crystalline structure under X-ray diffraction analysis and a type II polymorph under DSC analysis. Ultrasonic treatment for the re-dispersed starch-CLA complex in water resulted in the reduction of hydrodynamic diameter of the complex particles to 201.5nm. The dispersion exhibited a zeta potential of -27.0mV and remained stable in an ambient storage without forming precipitates for more than 4weeks. PMID:27283663

  4. Molecular Modeling of Ammonium, Calcium, Sulfur, and Sodium Lignosulphonates in Acid and Basic Aqueous Environments

    Science.gov (United States)

    Salazar Valencia, P. J.; Bolívar Marinez, L. E.; Pérez Merchancano, S. T.

    2015-12-01

    Lignosulphonates (LS), also known as lignin sulfonates or sulfite lignin, are lignins in sulfonated forms, obtained from the "sulfite liquors," a residue of the wood pulp extraction process. Their main utility lies in its wide range of properties, they can be used as additives, dispersants, binders, fluxing, binder agents, etc. in fields ranging from food to fertilizer manufacture and even as agents in the preparation of ion exchange membranes. Since they can be manufactured relatively easy and quickly, and that its molecular size can be manipulated to obtain fragments of very low molecular weight, they are used as transport agents in the food industry, cosmetics, pharmaceutical and drug development, and as molecular elements for the treatment of health problems. In this paper, we study the electronic structural and optical characteristics of LS incorporating ammonium, sulfur, calcium, and sodium ions in acidic and basic aqueous media in order to gain a better understanding of their behavior and the very interesting properties exhibit. The studies were performed using the molecular modeling program HyperChem 5 using the semiempirical method PM3 of the NDO Family (neglect of differential overlap), to calculate the structural properties. We calculated the electronic and optical properties using the semiempirical method ZINDO / CI.

  5. Humic Acid Degradation via Solar Photo-Fenton Process in Aqueous Environment

    Directory of Open Access Journals (Sweden)

    Seyed Ali Sajjadi

    2015-08-01

    Full Text Available Control of mutagenic and carcinogenic disinfection by-products, particularly Trihalomethanes (THMs and Halo Acetic Acids (HAAs in water treatment process is critical, due to their adverse effects on human health. Generally, reducing the toxicity of these by-products hinges on prior removal of the precursor materials, such as Humic Acid (HA in drinking water. This study was conducted to investigate the role of some parameters that could affect the removal of HA, including HA (5 and 10 ppm and H2O2 (20, 40, 60, and 80 ppm initial concentrations, Iron (II, sulfate heptahydrate dosage (4, 8, 12, and 16 ppm, pH (2, 3, 4 and 5, Oxidation time (5, 10, 15 and 30 min, and Sunlight levels (322±13 kWm-2. To accelerate the process of HA removal, the Solar Photo-Fenton (SPF process was employed by direct irradiation of converged sunlight in a Parabolic Trough Collectors (PTC, with 3m2 effective area. HA levels were measured via quantifying Dissolved Organic Carbon (DOC concentrations by means of a TOC Analyzer method. The results showed that the SPF process is under control of the Fe & H2O2 ratio, the Fe2+ dosage and especially the pH quantity. In optimal condition, (pH: 4, oxidation time: 30min, initial HA levels: 50 ppm, H2O2 concentrations: 20 ppm Fe+2 levels: 4 ppm, the study found more than 98% DOC removal. In conclusion, the SPF, as an economically effective technique, could be applied for the removal of HA in aqueous environments.

  6. Adsorption of Benzoic Acid in Aqueous Solution by Bagasse Fly Ash

    Science.gov (United States)

    Suresh, S.

    2012-09-01

    This paper reports the studies on the benzoic acid (BA) onto bagasse fly ash (BFA) was studied in aqueous solution in a batch system. Physico-chemical properties including surface area, surface texture of the GAC before and after BA adsorption onto BFA were analysed using X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The optimum initial pH for the adsorption of BA was found to be 5.56. The adsorbent dose was 10 g/l for BFA and the equilibrium time 8 h of reaction. Pseudo first and second order models were used to find the adsorption kinetics. It was found that intraparticle diffusion played important role in the adsorption mechanisms of BA and the adsorption kinetics followed pseudo-second order kinetic model rather than the pseudo first order kinetic model. Isotherm data were generated for BA solution having initial concentrations of BA in the range of 10-200 mg/l for the BFA dosage of 10 g/l at temperatures of 288, 303, and 318 K. The adsorption of BA onto BFA was favorably influenced by an increase in temperature. Equilibrium data were well represented by the Redlich-Peterson isotherm model. Values of the change in entropy ( ΔS 0), heat of adsorption ( ΔH 0) for adsorption of BA on BFA was found to be 120.10 and 19.61 kJ/mol respectively. The adsorption of BA onto BFA was an endothermic reaction. Desorption of BA from BFA was studied by various solvents method. Acetic acid was found to be a better eluant for desorption of BA with a maximum desorption efficiency of 55.2 %. Owing to its heating value, spent BFA can be used as a co-fuel for the production of heat in boiler furnaces.

  7. Lipase in biphasic alginate beads as a biocatalyst for esterification of butyric acid and butanol in aqueous media.

    Science.gov (United States)

    Ng, Choong Hey; Yang, Kun-Lin

    2016-01-01

    Esterification of organic acids and alcohols in aqueous media is very inefficient due to thermodynamic constraints. However, fermentation processes used to produce organic acids and alcohols are often conducted in aqueous media. To produce esters in aqueous media, biphasic alginate beads with immobilized lipase are developed for in situ esterification of butanol and butyric acid. The biphasic beads contain a solid matrix of calcium alginate and hexadecane together with 5 mg/mL of lipase as the biocatalyst. Hexadecane in the biphasic beads serves as an organic phase to facilitate the esterification reaction. Under optimized conditions, the beads are able to catalyze the production of 0.16 mmol of butyl butyrate from 0.5 mmol of butyric acid and 1.5 mmol of butanol. In contrast, when monophasic beads (without hexadecane) are used, only trace amount of butyl butyrate is produced. One main application of biphasic beads is in simultaneous fermentation and esterification (SFE) because the organic phase inside the beads is very stable and does not leach out into the culture medium. SFE is successfully conducted with an esterification yield of 6.32% using biphasic beads containing iso-octane even though the solvent is proven toxic to the butanol-producing Clostridium spp. PMID:26672465

  8. Aqueous extract ofOcimum gratissimum Linn and ascorbic acid ameliorate nicotine-induced cellular damage in murine peritoneal macrophage

    Institute of Scientific and Technical Information of China (English)

    Santanu Kar Mahapatra; Subhankari Prasad Chakraborty; Somenath Roy

    2010-01-01

    Objective:To test thein vitro protective role of aqueous extract ofOcimum gratissimumLinn. (O. gratissimum) and ascorbic acid against nicotine-induced murine peritoneal macrophage. Methods: Peritoneal macrophages from mice were treated with nicotine (10mM), nicotine (10 mM) with aqueous extract ofO. gratissimum (1 to25 μg/mL), and nicotine (10 mM) with ascorbic acid (0.01 mM) for12h in cell culture media, while the control group was treated with culture media. Levels of free radical generation, lipid peroxidation, protein carbonyls, oxidized glutathione levels andDNA damage were observed and compared.Results:Phytochemical analysis of aqueous extract has shown high amount of phenolics and flavonoids compound present in it. The significantly increased free radical generation, lipid peroxidation, protein carbonyls, oxidized glutathione levels andDNA damage were observed in nicotine-treated group as compared to the control group; those were significantly reduced in aqueous extract ofO. gratissimum and ascorbic acid supplemented groups. Moreover, significantly reduced antioxidant status in nicotine exposed murine peritoneal macrophage was effectively ameliorated by these two products. Among the different concentration of aqueous extract ofO. gratissimum, the maximum protective effect was observed at 10 μg/mL which does not produce any significant change in the normal cell.Conclusions:These findings suggest the potential use and beneficial role ofO. gratissimum as a modulator of nicotine-induced cellular damage in murine peritoneal macrophage.

  9. Synthesis of iron oxide nanoparticles under oxidizing environment and their stabilization in aqueous and non-aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Maity, D. [Materials Science Programme, Indian Institute of Technology Kanpur, Kanpur 208016 (India); Agrawal, D.C. [Materials Science Programme, Indian Institute of Technology Kanpur, Kanpur 208016 (India)]. E-mail: agrwald@iitk.ac.in

    2007-01-15

    Synthesis of magnetite (Fe{sub 3}O{sub 4}) nanoparticles under oxidizing environment by precipitation from aqueous media is not straightforward because Fe{sup 2+} gets oxidized to Fe{sup 3+} and thus the ratio of Fe{sup 3+}:Fe{sup 2+}=2:1 is not maintained during the precipitation. A molar ratio of Fe{sup 3+}:Fe{sup 2+} smaller than 2:1 has been used by many to compensate for the oxidation of Fe{sup 2+} during the preparation. In this work, we have prepared iron oxide nanoparticles in air environment by the precipitation technique using initial molar ratios Fe{sup 3+}:Fe{sup 2+}{<=}2:1. The phases of the resulting powders have been determined by several techniques. It is found that the particles consist mainly of maghemite with little or no magnetite phase. The particles have been suspended in non-aqueous and aqueous media by coating the particles with a single layer and a bilayer of oleic acid, respectively. The particle sizes, morphology and the magnetic properties of the particles and the ferrofulids prepared from these particles are reported. The average particle sizes obtained from the TEM micrographs are 14, 10 and 9 nm for the water, kerosene and dodecane-based ferrofluids, respectively, indicating a better dispersion in the non-aqueous media. The specific saturation magnetization ({sigma}{sub s}) value of the oleic-acid-coated particles ({approx}53 emu/g) is found to be lower than that for the uncoated particles ({approx}63 emu/g). Magnetization {sigma}{sub s} of the dodecane-based ferrofluid is found to be 10.1 emu/g for a volume fraction of particles {phi}=0.019. Zero coercivity and zero remanance on the magnetization curves indicate that the particles are superparamagnetic (SPM) in nat0009u.

  10. Radiation induced depolymerization of hyaluronic acid (HA) in aqueous solutions at pH 7. 4. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lal, M.

    1985-10-01

    Radiolytic depolymerization of hyaluronic acid (HA, a heteropolysaccharide) in aqueous solutions under a variety of conditions demonstrates that the damaging effect of radiolytic radical species is in the following order: OH > esub(aq)sup(-) > Osub(2). Cysteine, penicillamine and dithiothreitol were found to protect against primary radiolytic species. The results point out that the enzyme superoxide dismutase (SOD) and the above three thiols do not protect against the radiolytic species generated by the Mg-irradiation of aerated sodium formate solutions. The results also indicate that the reaction between COsub(2) anion and hyaluronic acid is faster than that between Osub(2) and hyaluronic acid and that COsub(2) anions are not scavenged by superoxide dismutase. The results further suggest that t-buthanol radicals interact with hyaluronic acid and reduce the viscosity of HA solutions. Preliminary pulse radiolysis experiments do demonstrate a reaction between COsub(2) radical and hyaluronic acid.

  11. THERMODYNAMIC STUDY ON ADSORPTION OF AROMATIC SULFONIC ACIDS ONTO MACROPOROUS WEAK BASE ANION EXCHANGER FROM AQUEOUS SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    Chao Long; Quan-xing Zhang; Ai-min Li; Jin-long Chen

    2004-01-01

    The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, ptoluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy,and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.

  12. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension using hydrophobically modified poly(acrylic acid).

    Science.gov (United States)

    Chen, J; Chen, M C

    2011-01-01

    A series of hydrophobically modified poly(acrylic acid) (PAA), poly(2-phenoxyethyl acrylate-co-acrylic acid) (poly(PHEA-co-AA)), have been synthesized and characterized by Ubbelohde type viscometry, Nuclear Magnetic Resonance (1H NMR) spectrometry and Differential Scanning Calorimetry (DSC). The shear thinning Non-Newtonian fluid behavior of their aqueous solution and the dependence on pH and hydrophobic group contents were found through apparent viscosity and rheological property investigating. Decolourization performance in C. I. Vat Yellow 1 aqueous suspension was evaluated through visible absorbance data. Decolourization performance of hydrophobically associated polymer indicates two times better than that of PAA. The quantitative relationship was mainly studied. PMID:21866762

  13. Viscosities of oxalic acid and its salts in water and binary aqueous mixtures of tetrahydrofuran at different temperatures

    Indian Academy of Sciences (India)

    M L Parmar; M K Guleria

    2005-07-01

    Relative viscosities for the solutions of oxalic acid and its salts, viz. ammonium oxalate, sodium oxalate and potassium oxalate, at different concentrations have been determined in water and in binary aqueous mixtures of tetrahydrofuran (THF) [5, 10, 15 and 20% by weight of THF] at 298.15 K, and in water and in 5% (w/w) THF + water at five different temperatures. The data have been evaluated using the Jones-Dole equation and the obtained parameters have been interpreted in terms of solute-solute and solute-solvent interactions. The activation parameters of viscous flow have been obtained which depicts the mechanism of viscous flow. The oxalic acid and its salts behave as structure breakers in water and in binary aqueous mixtures of THF.

  14. Analysis of. gamma. -radiolysis products of aqueous solutions of esters of aliphatic amino acids by the PMR method

    Energy Technology Data Exchange (ETDEWEB)

    Panin, V.I.; Sidorov, P.S.; Usatyi, A.F.

    1987-09-01

    The ..gamma..-radiolysis of aqueous solutions of methyl esters of aliphatic amino acids and peptides was investigated by the method of nuclear (proton) magnetic resonance (PMR). The resonance lines appearing in the PMR spectra of the irradiated systems were identified, and a conclusion was drawn about the molecular structure of the radiolysis products. The kinetics of the accumulation of radiolysis products was studied, and the values of their radiation yields were estimated.

  15. Structural Evolution of Molybdenum Carbides in Hot Aqueous Environments and Impact on Low-Temperature Hydroprocessing of Acetic Acid

    OpenAIRE

    Jae-Soon Choi; Viviane Schwartz; Eduardo Santillan-Jimenez; Mark Crocker; Samuel A. Lewis; Michael J. Lance; Meyer, Harry M.; More, Karren L.

    2015-01-01

    We investigated the structural evolution of molybdenum carbides subjected to hot aqueous environments and their catalytic performance in low-temperature hydroprocessing of acetic acid. While bulk structures of Mo carbides were maintained after aging in hot liquid water, a portion of carbidic Mo sites were converted to oxidic sites. Water aging also induced changes to the non-carbidic carbon deposited during carbide synthesis and increased surface roughness, which in turn affected carbide pore...

  16. Thermo - Acoustical Studies on Interionic Interactions of Some α-Amino Acids in Aqueous Sucrose Solution at Varying Mass Percentages.

    Directory of Open Access Journals (Sweden)

    S.Thirumaran

    2014-03-01

    Full Text Available The present study deals with the structure-making and breaking behaviour of some alpha-amino acids in aqueous sucrose (disaccharide solution at 301.15K. Experimental values of density, viscosity and speed of sound were carried out on the ternary mixtures of water +sucrose + amino acids namely (L-asparagine, L-glutamine L-serine and L-threonine at 301.15K. The binary solvent mixtures was prepared by taking sucrose at different mass percentages, say at 0%, 5%, 10%, 15%, 20%, and 25% was added with water. The given amino acids under study were added with aqueous solvent under different molarities at normal atmospheric pressure. The related and relevant parameters correlated to our present study such as adiabatic compressibility (b, molar hydration number (nH, apparent molar compressibility (jK, apparent molar volume (jV, limiting apparent molar compressibility (, limiting apparent molar volume ( and their associated constants (SK, SV, partial transfer volume (∆ from water to aqueous solution and viscosity B-Coefficient of Jones-Dole equations were meticulously evaluated and eventually this present study predicts dominance of hydrophilic –ionic interactions in the solution. Besides, our investigation also explores about the presence of possible interionic interactions such as solute-solvent, solute-solute, ion-solvent and ion-ion in the solution.

  17. Influence if acidity and concentration of aqueous uranyl nitrate solutions on the efficiency of uranium absorption by hydrolytic wood lignin

    International Nuclear Information System (INIS)

    Efficiency of uranium(VI) absorption by hydrolytic wood lignin from uranyl nitrate aqueous solutions under static conditions at room temperature, depending on solution acidity and uranium concentration, was studied using the methods of elementary analysis and IR spectroscopy. It was ascertained that hydrolytic lignin manifests a high ability to strong uranium(VI) absorption from low-acid and alkaline solutions. Interaction of uranium(VI) and hydrolytic lignin occurs both according to ion exchange mechanism and at the expense of donor-acceptor bonds formation

  18. The Kinetic Aspects of the Interaction of Nitrite Ions with Sulfanilic Acid and 1-Naphthylamine in Aqueous and Micellar Media

    Science.gov (United States)

    Korneeva, O. I.; Chernova, R. K.; Doronin, S. Yu.

    2008-04-01

    The kinetics of the reaction of nitrite ions with sulfanilic acid and 1-naphthylamine in aqueous and micellar (sodium dodecyl sulfate) media was studied step-by-step. The diazotization of sulfanilic acid with the nitrite ion was found to occur virtually instantaneously. Anionic surfactant micelles did not influence the rate of this reaction. The calculated effective rate constants and activation energies of the azo coupling reaction between synthesized sulfophenyldiazonium and 1-naphthylamine showed that the passage from water into the micellar medium decelerated the reaction. It was found that sodium dodecyl sulfate micelles played the role of a reagent separator.

  19. A study of partial molar volumes of citric acid and tartaric acid in water and binary aqueous mixtures of ethanol at various temperatures

    Indian Academy of Sciences (India)

    M L Parmar; R K Awasthi; M K Guleria

    2004-01-01

    Partial molar volumes of citric acid and tartaric acid have been determined in water and binary aqueous mixtures of ethanol (5, 10, 15, 20 and 25% by weight of ethanol) at different temperatures and acid concentrations from the solution density measurements. The data have been evaluated by using Masson equation and the obtained parameters have been interpreted in terms of solute-solvent interactions. The partial molar volumes vary with temperature as a power series of temperature. Structure making/breaking capacities of the organic acids have been inferred from the sign of [2$\\phi^{0}_{v}$/2], i.e. secondderivative of partial molar volume with respect to temperature at constant pressure. Both the organic acids behave as structure breakers in water and water + ethanol.

  20. Enhanced ozonation of dichloroacetic acid in aqueous solution using nanometer ZnO powders.

    Science.gov (United States)

    Zhai, Xu; Chen, Zhonglin; Zhao, Shuqing; Wang, He; Yang, Lei

    2010-01-01

    Nanometer zinc oxide (ZnO) powders were used as a catalyst to enhance the ozonation for the degradation of dichloroacetic acid (DCAA) in aqueous solution. The batch experiments were carried out to investigate the effects of key factors such as catalyst dosage, ozone dosage, solution pH and tert-butyl alcohol (t-BuOH) on the degradation efficiency of DCAA. Density functional theory (DFT) was adopted to explore the mechanism of generating hydroxyl radical (*OH) on the ZnO surface. The results showed that adsorption and ozonation processes were not effective for DCAA removal, and the addition of ZnO catalyst improved the degradation efficiency of DCAA during ozonation, which caused an increase of 22.8% for DCAA decomposition compared to the case of ozonation alone after 25 min. Under the same experimental conditions, the DCAA decomposition was enhanced by increasing catalyst dosage from 100 to 500 mg/L and ozone dosage from 0.83 to 3.2 mg/L. The catalytic ozonation process is more pronounced than the ozonation process alone at pH 3.93, 6.88, and 10. With increasing the concentration of t-BuOH from 10 to 200 mg/L, the degradation of DCAA was significantly inhibited in the process of catalytic ozonation, indicating that ZnO catalytic ozonation followed *OH reaction mechanism. Based on the experimental results and DFT analysis, it is deduced that the generation of *OH on the ZnO surface is ascribed to the adsorption of molecule ozone followed by the interaction of adsorbed ozone with active sites of the catalyst surface. It is also concluded that ZnO may be an effective catalyst for DCAA removal, which could promote the formation of *OH derived from the catalytic decomposition of ozone. PMID:21235181