bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrogenation of methyl sorbate and soybean esters with polymer‐bound metal catalysts
Authors: Frankel E. N. , Friedrich J. P. , Bessler T. R. , Kwolek W. F. , Holy N. L. 
Published: July 2007

AbstractNew polymer‐bound hydrogenation catalysts were made by complexing PdCl2, RhCl3·3H2O, or NiCl2 with anthranilic acid anchored to chloromethylated polystyrene. The Pd(II) and Ni(II) polymers were reduced to the corresponding Pd(O) and Ni(O) catalysts with NaBH4. In the hydrogenation of methyl sorbate, these polymer catalysts were highly selective for the formation of methyl 2‐hexenoate. The diene to monoene selectivity decreased in the order: Pd(II), Pd(O), Rh(I), Ni(II), Ni(O). Kinetic studies support 1,2‐reduction of the Δ4 double bond of sorbate as the main path of hydrogenation. In the hydrogenation of soybean esters, the Pd(II) polymer catalysts proved superior because they were more active than the Ni(II) polymers and produced lesstrans unsaturation than the Rh(I) polymers. Hydrogenation with Pd(II) polymers at 50~100 C and 50 to 100 psi H2 decreased the linolenate content below 3% and increasedtrans unsaturation to 10~26%. The linolenate to linoleate selectivity ranged from 1.6 to 3.2. Reaction parameters were analyzed statistically to optimize hydrogenation. Recycling through 2 or 3 hydrogenations of soybean esters was demonstrated with the Pd(II) polymers. In comparison with commercial Pd‐on‐alumina, the Pd(II) polymers were less active and as selective in the hydrogenation of soybean esters but more selective in the hydrogenation of methyl sorbate.
Determination of phosphorus in oils using oxygen bomb ashing
Authors: Yuen W. K. , Kelly P. C. 
Published: July 2007

AbstractA fast method for phosphorus determination in an oil matrix is described. The principle of the method is similar to that of the AOCS method, but the ashing of the oil is accelerated using an oxygen bomb. In addition, a rapid molybdovanadate reagent is used for colorimetry rather than the molybdenum blue reagents specified in the AOCS method. Agreement with the air ashing procedure averages less than 5% difference above 10 μg/g. The detection limit is in the order of 1~2 μg/g.
Polymorphism of pos. I. occurrence and polymorphic transformation
Authors: Arishima T. , Sagi N. , Mori H. , Sato K. 
Published: July 2007

AbstractPolymorphic behavior of 1,3‐rac‐palmitoyl‐stearoy 1‐2‐oleoylglycerol, 99.9% purity (POS) was examined by X‐ray diffraction (XRD), differential scanning calorimetry (DSC), solubility measurements and optical microscopy in comparison with 1,3‐dipalmitoyl‐2‐oleoylglycerol (POP) and 1,3‐distearoyl‐2‐oleoylglycerol (SOS). Melt crystallization and solvent crystallization were examined for the occurrence of metastable and stable polymorphs. The number of independent polymorphs was four; α,δ, pseudoβ′ andβ. The lowest melting form, α, was identical to that commonly observed in POP and SOS lowest melting forms. As to the highest melting form,β, the XRD shortspacing pattern was identical toβ1 of POP and SOS. This is consistent with crystal habit:β single crystals of POS showed the same shape as those of β1 of POP and SOS. However, the melting point ofβ (POS), 35.9°C, was lower than those ofβ1 of POP, 36.7°C, and of SOS, 43.0°C. Correspondingly, solubility ofβ of POS was lower than that of β1 of POP below about 13°C, but higher above 13°C. POS did not possessβ2, which is the second stable form in POP and SOS. Two forms of6 and pseudoβ′ occurred, the latter being more stable. The structural properties ofδ showed thatδ is not identical toγ previously observed in POP and SOS. Transformation behavior from the metastable to stable polymorphs of POS showed some differences from those of POP and SOS.
Geometrical isomers of linolenic acid in low‐calorie spreads marketed in France
Authors: Wolff Robert L. , Sebedio Jean‐Louis 
Published: July 2007

AbstractThe fatty acid compositions of 20 samples of low‐calorie spreads marketed in France have been examined by gasliquid chromatography (GLC) of their isopropyl esters on a fused silica capillary column coated with 100% cyanopropyl polysiloxane. Spreads containing linolenic acid at a level of 2.3% or higher (5 out of the 20 samples under study) also containtrans‐ 18:3 isomers. These were identified, after fractionation of their isopropyl esters by thin‐layer chromatography (TLC) on silica‐gel plates impregnated with AgNO3, by GLC on two capillary columns of different polarities and comparison of their equivalent chain lengths with those of authentic standards. Identifications were supported by GLC/mass spectrometry of the dimethyl esters resulting from ozonolysis in BF3/methanol of the monoenes isolated by AgNO3‐TLC after hydrazine reduction of 18:3 isomers. 9c,12c,15t‐18:3 and 9t,12c,15c‐18:3 were found to be the most abundant 18:3 isomers in the spreads, with small amounts of 9c,12t,15c‐18:3. These isomers occurred in the relative proportions 52–55, 41–42 and 4–6%, respectively. These proportions are independent of the origin of the sample. The tentatively identified 9t,12c,15t‐18:3 also occurred in some instances. In 2 of the spreads, total geometrical isomers of linolenic acid accounted for 0.9–1% of the total fatty acids (up to 28% of the total 18:3n‐3 fraction). The presence of 18:3n‐3 geometrical isomers in the spreads is likely due to rapeseed or soybean oils that were deodorized under rather harsh conditions before these were blended with other fats or oils. Partial hydrogenation of these oils may also contribute to accumulation of the same linolenic acid isomers in the spreads.
Linalyl acetate and methyl silicone effects on cholesterol and triglyceride oxidation in heated lard
Authors: Yan Pearlly S. , White Pamela J. 
Published: July 2007

AbstractThe effectiveness of linalyl acetate (LA) at 0.02 and 0.04% as a high‐temperature antioxidant was tested in lard with two levels (2 times and 10 times) of added cholesterol. Lard samples with and without added LA or methyl silicone (MS, 0.2 and 1.0 ppm) and a control with no additives were heated at 180°C for 10 hr/day for up to 240 hr. The loss of cholesterol, the formation of cholesterol oxidation products (COP) and the percentage fatty acid retention were measured during the heating periods. Addition of 1.0 ppm MS was significantly effective in reducing the loss of fatty acids (p<0.0005) in lard with 2 times the added cholesterol, but MS at 0.2 ppm was not effective in lard with 10 times the added cholesterol. Addition of LA at 0.02 and 0.04% had little effect at reducing changes in cholesterol loss, COP formation and fatty acid loss in lard samples with both cholesterol levels. But there was a tendency for MS and 0.04% LA to reduce formation of some COP in lard containing 2 times the added cholesterol and to reduce the loss of cholesterol.
Minor components responsible for flavor reversion of soybean oil
Authors: Endo Yasushi , Endo Hiromi , Fujimoto Kenshiro , Kaneda Takashi 
Published: July 2007

AbstractEdible refined, bleached and deodorized (RBD) soybean oil was fractionated by silicic acid column chromatography to identify minor components responsible for flavor reversion. Minor components from oil eluted with diethyl ether/n‐hexane (1:1) were compared with those from corn and canola oils. All vegetable oils contain free fatty acids, diglycerides and sterols as major ingredients in this fraction. However, unusual triglycerides consisting of 10‐oxo‐8‐octadecenoic acid and 10‐and 9‐hydroxy octadecanoic acids were detected in RBD and crude soybean oils.
A wet process technology applied to jojoba seed to obtain oil and detoxified protein meal
Authors: Lanzani A. , Bondioli P. , Brillo A. , Cardillo M. , Fedeli E. , Ponzetti A. , Pieralisi G. 
Published: July 2007

AbstractAn industrial wet process to obtain oil and meal from jo‐joba was set up. The process sequence consists of breaking the seeds, homogenizing with water of suitable pH and temperature, and centrifuging to accomplish separation into oil, process water and wet meal. Oil is obtained with a yield of 70–75% and requires no supplementary refining treatment for the industrial purposes for which it is destined. The meal obtained is devoid of the toxic components simmondsin and simmondsin‐2′ ferulate, and the protein content may be considered unchanged. The procedure contemplates a drying treatment for the meal with a view to using it as animal feed. This system is simple, economical and flexible in use.
Electron microscopy of soybean lipid bodies
Authors: Bair C. W. , Snyder H. E. 
Published: July 2007

AbstractSoybean lipid bodies in situ are small (0.2~0.5μm in diameter) and have an affinity for plasmalemma, protein bodies, endoplasmic reticulum and other cell organnelles but not for mitochondria or nuclei. Isolated lipid bodies contain 15% protein after extensive washing and have densities ranging from less than 1.0066 to 1.0788. We concluded that lipid bodies are surrounded by a specific delimiting membrane.
High performance liquid chromatographie analysis of intact and partially biodegraded linear alkylbenzene sulfonates
Authors: Linder D. E. , Allen M. C. 
Published: July 2007

AbstractA high performance liquid chromatography (HPLC) method for the determination of intact and partially degraded linear alkyl‐benzene sulfonate (LAS) was developed. The LAS degradation products resulting from a semicontinuous activated sludge (SCAS), a die‐away CO2 and a simulated river die‐away study were quanti‐tatively determined by HPLC equipped with a reversed‐phase column using a tetrahydrofuran/water/Pic A solution as the mobile phase. The column effluent was monitored with a fluorescence spectrophotometer that was operated at an excitation wavelength of 232 nm and an emission wavelength of 290. Compounds investi‐gated included both single‐and mixed‐carbon‐range materials. The HPLC method shows good correlations with MBAS for intact LAS material. The most significant advantage of this method over MBAS is it ability to quantitatively determine partially degraded intermediates and the disappearance of those intermediates. This method, when using the fluorescence detection system, is selective for sulfonated ring structures with more than one alkyl carbon. The sensitivity of the method is in the 0.05‐ppm range. It can be used not only for samples from laboratory experiments but also for sewage plant influents, effluents and river waters.
A facile route for synthesis of long‐chain RAC‐1‐S‐alkylglycerols
Authors: Rao B. V. S. K. , Subbarao R. 
Published: July 2007

AbstractAlkyl allyl thioethers were prepared by reaction of longchain primary thiols in hexane with allyl bromide in the presence of a phase transfer catalyst (tetrabutylammonium bromide), and aqueous alkali and were hydroxylated to rac‐1‐S‐alkylglycerols by means of a novel reagent, cetyltrimethylammonium permanganate, in dichloromethane.
Lipid composition of murraya koenigii seed
Authors: Hemavathy J. 
Published: July 2007

AbstractTotal seed lipids extracted fromMurraya koenigii (Linn), Rutaceae amounted to 4.4% of the dry seed. The total lipids consisted of 85.4% neutral lipids, 5.1% glycolipids and 9.5% phospholipids. Neutral lipids consisted of 73.9% triacylglycerols, 10.2% free fatty acids and small amounts of diacylglycerols, monoacylglycerols and sterols. At least five glycolipids and seven phospholipids were identified. Sterylglucoside and acylated sterylglucoside were major glycolipids, while digalactosyldiacylglycerol, monogalac‐tosyldiacylglycerol and monogalactosylmonoacylglycerol were present in small quantities. The phospholipids consisted of phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylethanolamine and lysophosphatidylcholine as major phospholipids and minor quantities of phosphatidylinositol, phosphatidylglycerol and phosphatidic acid. The fatty acid composition of these different neutral lipids, glycolipids and phospholipids were determined.
A rapid method for analysis of tert‐butyl hydroquinone (TBHQ) in ethyl esters of fish oil
Authors: Icenhour Teresa P. , Van Dolah Frances M. 
Published: July 2007

AbstractA rapid, quantitative gas Chromatographic method is described for quantitating the phenolic antioxidant,tert‐ butyl hydroquinone (TBHQ), in fish oil ethyl esters. The procedure entails silyl derivatization of TBHQ in an acetonitrile solution of ethyl esters followed by capillary gas chromatography (GC) analysis with an internal standard method of quantitation. Average recoveries of spiked samples were 98% at the legal limit of .02% (200 μg/g). The method can accurately determine as little as 20 μ/g of TBHQ in ethyl esters of fish oil. The technique has been applied to ethyl esters of vegetable oils with equal success.
A comparative study on the susceptibilities of soybean, sunflower and peanut oils to singlet molecular oxygen photooxidation
Authors: Neumann Monica M. , Fusero Silvia N. , García Norman A. 
Published: July 2007

AbstractThe susceptibilities of crude soybean, sunflower and peanut oils to singlet oxygen photooxidation were determined in a kinetic study. The accumulation of photosensitized hydroperoxides, determined spectroscopically, and the quenching of singlet molecular oxygen phosphorescence by the crude oils and their fatty acid methyl esters were compared.The relative tendency to photooxidation for the oils and the methyl esters was soybean ≫ sunflower > peanut. This trend was independent of the method employed in the determination of initial photodamaging.Soybean oil was demonstrated to be the most unstable product, not only due to the presence of highly unsaturated fatty acids, but also due to the absence of natural constituents, capable of providing a protective antioxidant effect. This protection was more effective in sunflower and peanut oils.
Lipids and retroviruses
Authors: Raulin Jeanine 
Published: July 2007

AbstractThe role that lipids may play in enveloped viruses is revie ved. Small lipid molecules can influence retrovirus binding to cell receptors, plasma membrane fusion, and transcription. Palmitoylation following myristoylation of viral glycoproteins is required at the transmembrane level for signal transduction as well as for virion budding and maturation. Cholesterol, ether lipids, phospholipids, platelet‐activating factor, phosphatidic acids, diacyglycerols, and several analogs and derivatives influence human immunodeficiency virus (HIV) activity; when conjugated with inhibitors of the viral reverse transcriptase (RT) or aspartyl protease these compounds increase drug effectiveness. On the other hand,l‐carnitine, in association with the mitochondrial cardiolipins, inhibits myopathy due to continued prescription of drugs [AZT (zidovudine), ddl (didanoside), or ddC (zalcitabine)], and the redox couple of α‐lipoic‐dihydrolipoic acid prevents production of the reactive oxygen species that trigger apoptosis of infected cells, with sphingomyelin breakdown to ceramides. Retroviral infection induces a shift from phospholipid to neutral fat synthesis in host cells, and a long antiviral, i.e., antiprotease, treatment may lead to lipodystrophy. Multitherapy involving lipids and their analogs in association with anti‐RT and antiproteases might enhance the inhibition of growth and proliferation of retroviruses.
Accumulation of docosahexaenoic acid in phosphatidylserine is selectively inhibited by chronic ethanol exposure in C‐6 glioma cells
Authors: Kim Hee‐Yong , Hamilton Jillonne 
Published: July 2007

AbstractNeuronal membranes are highly enriched with docosahexaenoic acid (22∶6n−3), and its content can be altered by ethanol consumption. We have previously reported that the 22∶6n−3 status in membrane affects the biosynthesis of phosphatidylserine (PS), a phospholipid class which contains an exceptionally high proportion of 22∶6n−3. The aim of the present study is to investigate the effect of chronic ethanol exposure on PS accumulation in relation to the 22∶6n−3 status. C‐6 glioma cells were enriched with 25 μM 22∶6n−3 for 48 h and the PS accumulation was first evaluated in comparison to nonenriched cells as well as cells enriched with arachidonic acid (20∶4n−6). Electrospray liquid chromatography‐mass spectrometry analysis revealed that cells treated with 22∶6n−3 showed significantly higher accumulation of PS in comparison to nonenriched or 20∶4n−6‐enriched cells, primarily due to an increase of 1‐stearoyl‐2‐docosahexaenoyl‐glycerophosphoserine (18∶0,22∶6‐PS). Chronic ethanol exposure selectively affected the accumulation of PS in 22∶6n−3‐enriched cells. After cells were exposed to 20 or 50 mM ethanol for 4 wk, accumulation of 18∶0,22∶6‐PS upon 22∶6n−3 supplementation was significantly lower, resulting in a drastic reduction of total PS. Concomitantly, ethanol‐treated cells showed lower incorporation of serine in comparison to control cells. From these data, it was concluded that supplementation of cells with 22∶6n−3 promotes the accumulation of PS and chronic ethanol treatment diminishes this effect at least in part through impaired serine incorporation processes. Attenuated accumulation of 22∶6n−3 in PS and the reduction of PS thus may have significant implications in pathophysiological effects of ethanol, especially in tissues with abundant 22∶6n−3.
Mechanisms of tubulin modification by phosphatidylcholine hydroperoxides
Authors: Kawakami Misako , Ward Larry , Doi Hiroshi 
Published: July 2007

AbstractThe interaction of lipid peroxides with cellular proteins has been postulated to contribute to cellular aging. A potential target for such effects is tubulin, the building block of microtubules. We examined the concentration‐dependent effects of phosphatidylcholine hydroperoxides on the ability of tubulin to polymerize into microtubules. The results demonstrated that even very low concentrations of peroxides were sufficient to interfere with the tubulin and, therefore, the microtubule function. Decreased tubulin activity (as measured by tubulin GTPase activity) showed correlation with the modification of methionine and cysteine in tubulin and a change in the tubulin conformational state as indicated by fluorescence and ultraviolet spectroscopic measurements. As no effect on electric conductivity was observed, indicating that modulation of ionic binding was not involved, the interaction mechanism may be a hydrophobic one.
Biophysical studies and intracellular destabilization of pH‐sensitive liposomes
Authors: Van Bambeke Fran¢oise , Kerkhofs Anne , Schanck André , Remacle Claude , Sonveaux Etienne , Tulkens Paul M. , Mingeot‐Leclercq Marie‐Paule 
Published: July 2007

AbstractWe examined changes in membrane properties upon acidification of dioleoylphosphatidylethanolamine/cholesterylhemisuccinate liposomes and evaluated their potential to deliver entrapped tracers in cultured macrophages. Membrane permeability was determined by the release of entrapped calcein or hydroxypyrene‐1,3,6‐trisulfonic acid (HPTS)‐p‐xylene‐bis‐pyridinium bromide (DPX); membrane fusion, by measuring the change in size of the liposomes and the dequenching of octadecylrhodamine‐B fluorescence; and change in lipid organization, by31P nuclear magnetic resonance spectroscopy. Measurement of cell‐associated fluorescence and confocal microscopy examination were made on cells incubated with liposomes loaded with HPTS or HPTS‐DPX. The biophysical studies showed (i) a lipid reorganization from bilayer to hexagonal phase progressing from pH 8.0 to 5.0, (ii) a membrane permeabilization for pH<6.5, (iii) an increase in the mean diameter of liposomes for pH<6.0, and (iv) a mixing of liposome membranes for pH<5.7. The cellular studies showed (i) an uptake of the liposomes that were brought from pH 7.5–7.0 to 6.5–6.0 and (ii) a release of ∼15% of the endocytosed marker associated with its partial release from the vesicles (diffuse localization). We conclude that the permeabilization and fusion of pH‐sensitive liposomes occur as a consequence of a progressive lipid reorganization upon acidification. These changes may develop intracellular after phagocytosis and allow for the release of the liposome content in endosomes associated with a redistribution in the cytosol.
Determining double‐bond positions in monoenoic 2‐hydroxy fatty acids of glucosylceramides by gas chromatography‐mass spectrometry
Authors: Imai Hiroyuki , Yamamoto Kohei , Shibahara Akira , Miyatani Shuichi , Nakayama Takao 
Published: July 2007

AbstractWe applied a gas chromatography‐mass spectrometry (GC‐MS) method using dimethyl disulfide (DMDS) adducts and were able to determine the double‐bond positions in monounsaturated 2‐hydroxy fatty acids (2‐HFA). 2‐HFA methyl esters, prepared from the hydrolysate ofArabidopsis thaliana leaf glucosylceramides, were acetylated and methylthiolated. GC‐MS analysis of the resulting DMDS adducts showed simple mass spectra with recognizable molecular ions and a series of key fragment ions indicating the original double‐bond positions in the aliphatic chain. Based on this GC‐MS elucidation, we confirmed thatArabidopsis leaf glucosylceramides have C22, C23, C24, C25, and C26 chain length 2‐HFA with monounsaturation, and all their double bonds are placed at the n−9 position. This procedure is simple, time efficient, and highly sensitive.
Isomerization during hydrogenation. III. Linoleic acid
Authors: Allen Robert R. , Kiess Arthur A. 
Published: July 2007

SummaryThe isomerization that takes place during the catalytic hydrogenation of linoleic acid and methyl linoleate producescis andtrans 9, 10, 11, and 12 monoenes. The double bond at the 12 position appears to hydrogenate slightly faster than that in the 9 position. More octadecenoic acids with double bonds at the 10 or 11 positions are produced during a selective (high temperature, low pressure) hydrogenation than during a non‐selective process.Although the degree of selectivity of the hydrogenation is determined by the amount of isomerization of the original pentadiene system to a conjugated diene, only part of the methylene‐interrupted diene goes through this type of isomerization even during a highly selective hydrogenation.The half hydrogenation‐dehydrogenation reaction mechanism is applied to explain the simultaneous positional and geometrical isomerizations.
Glyceride analysis of palm oil after solvent fractionation
Authors: Tan B. K. , Hamilton R. J. , Berger K. G. 
Published: July 2007

AbstractA procedure is described for determing the triglyceride composition of palm oil and its fractions by the use of silver nitrate thin layer chromatography (TLC) and gas liquid chromatography (GLC). The triglycerides separated by silver nitrate TLC according to the number of double bonds are quantified using infrared spectroscopy before further analysis by GLC according to carbon number. The results from the two techniques enable the composition of the oil and fractions to be computed on a molecular basis in relation to fatty acid types. The potential application of this procedure is to analyze fractions obtained from the fractionation of oils and fats to which the 1,3‐Random‐2‐Random distribution theory is not applicable.
Branched fatty acids from the caustic oxidation of isotridecyl oxo bottoms
Authors: Lawson N. E. , Harding M. J. C. 
Published: July 2007

AbstractCaustic oxidation has been used to convert the complex residue from the isotridecyl alcohol process (“C13 oxo bottoms”) to simpler mixtures of highly branched, liquid carboxylic acids in about 65% combined yield. One of the products, produced in 34% yield, was a mixture of isotridecanoic acids formed mainly from C13 alcohol and its ester. It was composed of 85% primary carboxylic acids and 15% secondary. The high boiling acids were largely C26 secondary car‐boxylic acids formed by oxidation of aldol dimers. The relative rates of esterification were stearic:C13 acid:high boiling acids—1:0.35: 0.05. In addition, a 22% combined yield of neutrals consisting of saturated and unsaturated hydrocarbons and ethers was obtained.