bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass spectrometric evidence for the presence of platelet‐activating factor (1‐0‐alkyl‐2‐acetyl‐sn‐glycero‐3‐phosphocholine) in human amniotic fluid during labor
Authors: Nishihira Jun , Ishibashi Teruo , Imai Yoh , Muramatsu Toshio 
Published: November 2006

AbstractEvidence is presented for the existence of platelet‐activating factor (PAF) in human amniotic fluid during labor by gas‐liquid chromatographic (GLC) and mass‐spectrometric (MS) analysis. The unique ether‐linked phospholipid was identified only in an amniotic fluid obtained from women during labor, and its alkyl side chain was composed exclusively of octadecyl residue.
Effect of dietary vitamin E upon fluorescent compounds of the rat uterus
Authors: Csallany A. Saari , Ayaz K. Lund , Menken B. Zaspel 
Published: November 2006

AbstractSeveral water soluble and organic solvent soluble fluorescent peaks were observed in extracts of uteri from vitamin E deficient or supplemented rats following Sephadex column chromatography and spectrophotofluorometric analysis. Levels of one of the organic and two of the water soluble fluorescent peaks were found to be significantly higher in the uteri of vitamin E deficient rats than in vitamin E supplemented rats. Some of these fluorescent fractions may contribute to the brown discoloration that is known to occur in the uterus of vitamin E deficient animals.
Molecular species and fatty acid distributions of triacylglycerols from germinating soybean cotyledons
Authors: Yoshida Hiromi 
Published: November 2006

AbstractMolecular species and fatty acid distributions of triacylglycerols obtained from cotyledons of soybean seedlings were investigated. Changes observed in triacylglycerol content were closely related to levels of total lipids present in the cotyledons. At day 12 of seedling growth, ca. 85% of triacylglycerols had been consumed. Immediately after the beginning of imbibition the oil consisted of triacylglycerols with even carbon numbers (from C‐50 to C‐60) based on the combined length of the fatty acyl chains present in a triacylglycerol. The dominant components throughout germination were C‐52 and C‐54 triacylglycerols. Fourteen molecular species of triacylglycerols were identified in the cotyledons. As soybean seedlings grew, the percentages of triacylglycerols decreased to 0.9–36.2% during the 12 days. Triacylglycerols containing one or more saturated fatty acids were hydrolyzed slightly faster than other species. Unsaturated fatty acids were dominant in the 2‐position throughout germination. These results suggest the mechanism of initial triacylglycerol hydrolysis may be different in various molecular species.
Photosensitized oxidation of methyl linolenate monohydroperoxides: Hydroperoxy cyclic peroxides, dihydroperoxides and hydroperoxy bis‐cyclic peroxides
Authors: Neff W. E. , Frankel E. N. 
Published: November 2006

AbstractTo elucidate the biological and flavor significance of lipid secondary oxidation products, cyclic peroxides were prepared by photosensitized oxidation of the hydroperoxides in autoxidized methyl linolenate. The oxidation product was fractionated by silicic acid chromatography, followed by high pressure liquid chromatography (HPLC) on a microporous silica column. Products characterized by thin layer chromatography (TLC), gas chromatography (GC), ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS) included 6‐membered cyclic peroxides (9‐hydroperoxy‐10,13‐epidioxy‐11, 15‐and 16‐hydroperoxy‐12,15‐epidioxy‐9, 13‐octadecadienoates), 15‐membered cyclic peroxides (9‐hydroperoxy‐10,12‐epidioxy‐13,15‐ and 16‐hydroperoxy‐13, 5‐epidioxy‐9,11‐octadecadienoates), dihydroperoxides (9,12‐; 9,16‐; 10,12‐; 10,15‐; 10,16‐; 13,15‐; 13,16‐dihydroperoxy octadecatrienoates) and hydroperoxy bis‐cyclic peroxides, each with one 5‐and one 6‐membered ring (9‐hydroperoxy‐10,12,13,16‐bis‐epidioxy‐14‐ and 16‐hydroperoxy‐9,12,13, 15‐bis‐epidioxy‐10‐octadecenoates). The 6‐membered cyclic peroxides are formed by 1,4‐addition of singlet oxygen to the conjugated diene system in 9‐ and 16‐linolenate hydroperoxide isomers after their isomerization to thetrans, trans configuration. The bis‐cyclic peroxides are formed by 1,4‐addition of singlet oxygen to the hydroperoxy 5‐membered cyclic peroxides derived from the 12‐ and 13‐linolenate hydroperoxide isomers. Secondary oxidation products similar to those identified in this study previously have been shown to be important precursors of volatile compounds that may contribute to flavor deterioration of fat‐containing foods.
Mass spectrometric location of double bonds in unsaturated fatty acids including conjugated acids as their methoxybromo derivatives
Authors: Shantha N. C. , Kaimal T. N. B. 
Published: November 2006

AbstractMethoxybromo derivatives of unsaturated fatty acids including conjugated acids yield simple mass spectra and can be used to locate the position of double bonds in these acids. The derivatives are prepared under mild conditions by bromination of the unsaturated fatty acids in methanol. The method is illustrated with the methoxybromo derivatives from methyl esters of oleic, petroselenic, erucic, undecenoic, linoleic, linolenic, the conjugated diene acids from dehydrated castor oil, α‐eleostearic, punicic and parinaric acids. Unlike other methods using methoxy derivatives, the methoxybromo derivatives yield fewer ions, the diagnostic peaks forming the most intense ions of the spectra. While unambiguous double bond location is possible with monoenoic acids and conjugated fatty acids, only the end carbon atoms of the unsaturation system in nonconjugated polyenoic acids is located. But the characteristic appearance of fragments corresponding to [CH3(CH2)nCH(OMe)CH(Br)CH2−2H]+ and fragments 24 mass units higher than those which locate the end carbons in such fatty acids indicate a methylene‐interrupted system of double bonds.
Wide variations of plasma triglyceride concentrations in guinea pigs
Authors: Mori N. , Murase T. , Yamada N. , Arakawa N. , Takaku F. 
Published: November 2006

AbstractGuinea pigs have varying plasma triglyceride concentrations ranging from 28 to 1392 mg/dl, with relatively uniform plasma cholesterol and phospholipid levels. To understand why the animals exhibit such wide variations of plasma triglyceride concentrations, we have explored the triglyceride hydrolyzing system by measuring tissue lipoprotein lipase activities and plasma activator for the enzyme. Lipoprotein lipase activities of epididymal adipose tissue of these animals were 759±117 (mean±SE) n moles FFA·min−1·g wet tissue−1, markedly low compared with those of rats. There were no relationships between plasma triglyceride concentrations and tissue lipase activities. Plasma activator for lipoprotein lipase was lacking in this animal. Guinea pigs with ascorbic acid deficiency for 2 weeks also showed marked variations of plasma triglyceride concentrations, without any changes in tissue lipoprotein lipase activities. Low adipose tissue lipoprotein lipase activities with deficient plasma activator for the enzyme suggest that the lipoprotein lipase‐mediated triglyceride degradation could be impaired in this animal, and this may account for the marked variation of plasma triglyceride concentrations.
The positional distributions of fatty acids in the triacylglycerols and phosphatidylcholines of the intestinal and popliteal lymph and plasma of sheep
Authors: Christie W. W. , Clegg R. A. , Calvert D. T. , Noble R. C. 
Published: November 2006

AbstractAs part of a study of the contribution of the intestinal lymph lipoproteins and their lipid constituents to the plasma lipids in sheep, the positional distributions of the fatty acids in the triacyl‐sn‐glycerols and phosphatidylcholines in very low density/low density lipoprotein and high‐density lipoprotein fractions were determined by stereospecific analysis procedures. The triacyl‐sn‐glycerols of these lipoprotein fractions in intestinal lymph did not differ appreciably in structure and resembled the plasma triacyl‐sn‐glycerols in the composition of positionsn‐2 especially. However, there were appreciable amounts of the essential fatty acid, linoleic acid, in positionssn‐1 andsn‐3 of the triacylglycerols in lymph but not in plasma. This result is discussed in terms of the metabolism of the triacylglycerols of lymph after they enter the plasma as part of a mechanism for the conservation of essential fatty acids in ruminants. No differences of metabolic note were observed in the structures of the phosphatidylcholines between lipoprotein fractions and among tissues.
Activation of polyunsaturated fatty acids by rat tissues in vitro
Authors: Reddy T. Sanjeeva , Bazan Nicolas G. 
Published: November 2006

AbstractThe conversion of labeled palmitic, linoleic, arachidonic and docosahexaenoic acids to their respective acyl CoA’s was studied in homogenates and microsomes of rat tissues. The highest activity, both in homogenates and microsomes, was seen in liver and heart. There was moderate activity in retina, brain, lung, kidney and testes and the lowest activity was found in spleen. Docosahexaenoic acid was activated much less actively in heart tissue than the other fatty acids. In all tissues examined, the highest activation was observed with arachidonic acid and the lowest with docosahexaenoic acid. Except for liver, those tissues that contained high levels of docosahexaenoic acid also had the highest activation capacity for this fatty acid.
Short term essential fatty acid deficiency in rats. Influence of dietary carbohydrates
Authors: Trugnan G. , Thomas‐Benhamou G. , Cardot P. , Rayssiguier Y. , Bereziat G. 
Published: November 2006

AbstractThe effects of long term (8–14 wk) essential fatty acid (EFA)‐deprived diets in rats are well documented. In the present study, we compared, in weanling rats, the effect of a short term (two wk) hydrogenated coconut oil, EFA‐deprived, diet (D) with that of a corn oil, EFA‐adequate, diet (A), using either sucrose (SU) or starch (ST) as carbohydrate. After two wk, rats fed the sucrose/hydrogenated coconut oil diet developed some characteristic features of EFA deprivation: slower growth rate, decreases in linoleic and arachidonic acid of plasma phospholipids and an increase in n−9 eicosatrienoic acid of plasma phospholipids. When rats ate the starch/hydrogenated coconut oil diet, there was a similar decrease in linoleic acid of plasma phospholipids, but only a small effect on growth rate and no change in the arachidonic acid content of plasma phospholipids. EFA deprivation and sucrose had opposite effects on plasma triglyceride (TG) levels: deprivation induced a decrease, whereas the sucrose induced an increase in very low density lipoprotein (VLDL) triglycerides. The observed decrease in plasma triglyceride during EFA deporivation might result from an activation of lipoprotein lipase during the early stages of deprivation.
Changes in Δ5‐ and Δ7‐sterols during germination and seedling development ofCucurbita maximaduring germination and seedling development ofCucurbita maxima
Authors: Garg Vipin K. , Nes William R. 
Published: November 2006

AbstractWhile seeds ofCucurbita maxima contain both Δ5‐ and Δ7‐sterols, the former, which have been described earlier, now have been found to disappear during germination. This suggests that a function exists for the Δ5‐compounds only in the early part of the life cycle ofC. maxima, unlike most of the other higher plants studied. In contrast to the Δ5‐sterols, the level of Δ7‐sterols increased during germination as well as during seedling development and maturation. The period of transition between germination and seedling development appeared to be of special importance in terms of sterol changes. This period represented a surge of sterol biosynthesis with an ontogenetic shift in sterol composition from approximately equal amounts of 24α‐ and 24β‐ethyl stereochemistry to a predominance of the former. The sterol composition of the mature plants included only about 5% of the 24β‐ethylsterols. The configurational relationships were demonstrated by high resolution1H‐NMR. The sterols of the mature plants were: 25(27)‐dehydrochondrillasterol, 24β‐ethyl‐25(27)‐dehydrolathosterol, avenasterol, spinasterol, 22‐dihydrospinasterol and 24ξ‐methyllathosterol. Based on the changes which occurred in the relative amounts of the Δ7‐sterols, it did not appear that the Δ5‐components were being converted to their Δ7‐analogs.
Potential antineoplastic dihydroxy‐fatty acids
Authors: Piatak David M. , Tang Pui‐Fun Louisa 
Published: November 2006

AbstractThe fatty acid aglycones of two naturally occurring glycosides, one of which is reported to possess antitumor activity, were synthesized for biological evaluation. The preparation of 3,11‐dihydroxyhexadecanoic acid and 3,12‐dihydroxyhexadecanoic acid started with the monoethyl esters of nonanedioic acid and decanedioic acid, respectively, and proceeded through the corresponding C14 ketoesters, ketalesters, and ketalaldehydes and C16 ketalhydroxyesters and dihydroxyesters. Various products and intermediates were found to have no inhibitory action in the P388 lymphocytic leukemia screen. A rearrangement of the ethylene glycol ketal‐protecting group from the initially protected ketone group to a newly formed aldehyde moiety was observed.
Positional distribution of fatty acids in cardiolipin of mitochondria from 21‐day‐old rats
Authors: Wolff Robert L. , Combe Nicole A. , Entressangles Bernard 
Published: November 2006

AbstractPure cardiolipins (1,3‐diphosphatidylglycerol) were prepared from mitochondria of heart, liver and kidney from 21‐day‐old male Wistar rats and submitted toNaja naja venom phospholipase A2 (EC 3.1.1.4) action. Incubation conditions were controlled carefully, and a complete hydrolysis of cardiolipin to lysocardiolipin {di [1 (1″) acylsn‐glycero‐3‐phosphoryl] 1′, 3′‐sn‐glycerol} and fatty acids from positions 2 (2″) was obtained in less than two hr practically without side reactions. Cardiolipins from the three organs contained low levels of saturated fatty acids; stearic acid accounted for 0.4–0.7% and palmitic acid for 1.4–3.5% of total fatty acids. These percentages apparently depended on the organ. In all three cases, linoleic acid was the major component, but its percentage varied from 62–78% of total fatty acids. Acyl chains linked to positions 1 (1″) of all three cardiolipin preparations exhibited a similar pattern; they were composed of linoleic acid for 85–89%. This fatty acid also was the main component esterified at position 2 (2″), but its percentage was much more variable: from 39.8% in heart to 51.2% in kidney and 67.8% in liver mitochondria. The remaining acids comprised octadecenoic and polyunsaturated fatty acids with more than 18 carbon atoms in different proportions. As opposed to other phospholipids,cis‐vaccenic acid, and not oleic acid, was the main octadecenoic acid present in cardiolipins.Octadecenoic acids were nine‐ to 10‐fold more concentrated at positions 2 (2″) than at positions 1 (1″). The percentage ofcis‐vaccenic acid was four‐ to five‐fold higher than that of oleic acid at positions 2 (2″), whereas oleic acid dominated at positions 1 (1″). From results presented in this study and selected literature data, it may be concluded that fatty acids are asymmetrically distributed in cardiolipins of different origins, with linoleic acid showing a definite preference for position 1 (1″).
Physical state of inhibitor fatty acids and linoleate solutions under lipoxygenase assay conditions
Authors: Gibian Morton J. , Colanduoni John 
Published: November 2006

AbstractA variety of fatty acids, which are potential competitive inhibitors of soybean lipoxygenase (EC 1.13.11.12), give kinetically unstable mixtures in standard assay solutions containing linoleate (substrate). In the assay solution (pH 10, 0.1 M borate, 1.63% ethanol), each fatty acid by itself shows normal surface tension vs concentration behavior; but, despite a range of solubilization techniques in the presence of 10 μM or higher linoleate and low concentrations of these materials, irreproducible surface‐tension readings and inhibition kinetics results. This inhomogeneity (or kinetic instability) disappears as the concentration increases. Critical micelle concentration (CMC) values of mixtures are not additive, and binary mixture behavior depends on fatty acid structure. Several lines of observation, including CMC values and actual surface tension (γ) values for several systems, suggest premicellar heterodimer or higher mixed aggregate formation. Lipids with Ki significantly above the irreproducible surface‐tension range give good kinetic behavior, and Ki is reported. The results are in accord with earlier work on aspects of these systems. Complementary solution physical studies must be done for any kinetic (or specificity) determinations of enzymes using lipids.
Long‐chain acyl‐CoA levels in liver from rats fed high‐fat diets: Is it of significance for an increased peroxisomal β‐oxidation?
Authors: Nilsson A. , Thomassen M. S. , Christiansen E. 
Published: November 2006

AbstractThe levels of long‐chain acyl‐CoA in the livers of rats given diets containing various amounts of dietary oils were investigated. Increasing the amount of soybean oil in the diet from 5% to 25% (w/w) led to a 40% increase in long‐chain acyl‐CoA. With partially hydrogenated marine oil, a sigmoidal doseresponse curve was obtained, giving a 60% increase when 20% or more of this oil was in the diet.All high‐fat diets tested resulted in higher levels of long‐chain acyl‐CoA than the low‐fat control containing soybean oil. The increase was most prominent with partially hydrogenated marine and rapeseed oils.With diets containing partially hydrogenated marine oil, the ratio of long‐chain acyl‐CoA to acid‐soluble CoA was increased after 3 days, but decreased after 3 weeks, to a value similar to that observed in animals fed soybean oil because of an extensive increase in acid‐soluble CoA.Increased levels of long‐chain acyl‐CoA were also observed after clofibrate was administered, but the increase was less prominent than observed with high‐fat diets.When comparing the levels of long‐chain acyl‐CoA observed after 3 days on different diets with the peroxisomal β‐oxidation activity previously determined after 3 weeks on the corresponding diets, a straight line was obtained. These results are discussed in relation to the possibility that long‐chain acyl‐CoA induces peroxisomal β‐oxidation activity.
Comparative study of the molecular species of chloropropanediol diesters and triacylglycerols in milk fat
Authors: Kuksis A. , Marai L. , Myher J. J. , Cerbulis J. , Farrell H. M. 
Published: November 2006

AbstractIn an effort to establish the origin of the fatty acid esters of 3‐chloropropanediol, which recently have been isolated in small amounts from goat milk, we compared the molecular species composition of the chlorohydrin diesters and of goat milk triacylglycerols. The chloropropanediol diesters were found to be composed of molecular species containing C10−C18 fatty acids and corresponded closely in carbon number to those calculated for the long chain sn‐1,2‐diacyl‐glycerol moieties of goat milk triacylglycerols. The molecular species of goat milk total triacylglycerols contained C4−C18 fatty acids. It is suggested that triacylglycerols and chloropropanediol diesters are derived from the same pool of long chain fatty acids. A molecular distillate of bovine milk fat did not contain chloropropanediol diesters, while the available samples of human milk fat were shown to contain alkyldiacylglycerols as the major components of a neutral lipid fraction corresponding in polarity to the chloropropanediol diesters.
Partial specific volume and preferential hydration of low density lipoprotein subfractions
Authors: Kahlon Talwinder S. , Adamson Gerald L. , Glines Laura A. , Orr Joseph R. , Lindgren Frank T. 
Published: November 2006

AbstractWe have determined the partial specific volume () for five low density lipoprotein (LDL) subfractions (n=5–7) and evaluated preferential hydration (n=2) for LDL subfraction 3 in normolipoproteinemic subjects in order to characterize these highly atherogenic components of the human plasma lipoprotein spectra. Values for at 1 g were determined by sixth place density measurements of the solvent and lipoprotein solutions and carbon, hydrogen and nitrogen (CHN) absolute mass of the lipoprotein concentrations. Mean values for were 0.9757±0.0019, 0.9701±0.0007, 0.9674±0.0016, 0.9616±0.0016 and 0.9550±0.0025 ml/g for subfractions 1, 2, 3, 4 and 5, respectively. However, molecular densities (σ) obtained from ϱ(rho)=1/ for respective LDL subfractions were 1.0249, 1.0308, 1.0337, 1.0399 and 1.0471 g/ml, respectively. The preferential hydration of lipoprotein subfraction 3 (n=2) in NaCl/H2O solutions was 2.9–4.8 wt percent, whereas values were much lower (0.3–0.6 wt percent) in NaCl/NaBr/H2O solvent system. Unhydrated densities for LDL subfraction 3 (n=2) at 1 g (sixth‐place density meter) were 1.0287 and 1.0269 g/ml, whereas at 200,000 × g (used in D2O flotation ηFo vs ϱ determinations) both values were 1.0308 g/ml, indicating that these similar LDL fractions have 23 and 53% higher compressibility than the solvent at 200,000 × g force. It was observed that the linearity of ηFo vs ϱ may not be valid for solvents NaCl/NaBr/H2O of density as high as 1.4744 g/ml. Thus, flotation velocity data using extreme salt concentrations (1.4744 g/ml and higher) may be viewed with caution.
Complete separation of phospholipids from human heart combining two HPLC methods
Authors: Juanéda Pierre , Rocquelin Gérard 
Published: November 2006

AbstractThe separation of phospholipid classes from human heart was achieved in two steps by high performance liquid chromatography (HPLC) using a silica column with an ultraviolet spectromonitor at 206 nm. A complete partitioning of phosphatidylcholines (PC), phosphatidylethanolamines (PE), phosphatidylinositols (PI), phosphatidylserines (PS), cardiolipins (CL), lysophosphatidylcholines (LPC) and sphingomyelins (Sph) was obtained for further analysis.
Tissue distribution of phytanic acid and its analogues in a kinship with Refsum's disease
Authors: Yao Jeffrey K. , Dyck Peter James 
Published: November 2006

AbstractThree of six kin were identified, by high performance thin layer chromatography, capillary gas chromatography and mass spectrometry, as having phytanic acid storage disease. Phytanic acid was found in triacylglycerol and, to a lesser degree, in phosphatidylcholine and free fatty acids. An unsaturated analogue of phytanic acid was additionally identified in plasma and erythrocyte triacylglycerols. In plasma, branched chain fatty acids were primarily localized in the low density lipoprotein fraction. The concentration of plasma major fatty acids was not affected by the presence of these branched chain fatty acids. In contrast to plasma, only small amounts of phytanic acid were found in cerebrospinal fluid and biopsied sural nerve. The nerve phytanate was mainly associated with triacylglycerol in epineurial and perineurial tissues. Lack of phytanate accumulation in sural endoneurium, even in cases with severe fiber degeneration, suggests that demyelination in Refsum's disease may not be due to myelin instability resulting from the incorporation of branched chain fatty acids into peripheral nerve membrane.