bluuebunny/crossref_metadata_2025_split huggingface dataset:
New phospholipid fatty acids from the Caribbean spongeEctyoplasia ferox
Authors: Carbelleira Néstor M. , Maldonado Marie E. 
Published: November 2006

AbstractThe phospholipid fatty acids from the Caribbean spongeEctyoplasia ferox were studied. The novel fatty acids 25‐methyl‐5,9‐heptacosadienoic (1) and 26‐methyl‐5,9‐heptacosadienoic (2) were identified in 3.4 and 2.0% abundance, respectively, representing the longest set of Δ5,9iso andanteiso acids yet isolated from a marine sponge. The new acid 10,13‐dimethyltetradecanoic (3), the unusual acid 15‐methyl‐11‐hexadecenoic (4) and the also novel acid 9‐methyl‐11‐hexadecenoic (5) were also identified inE. ferox. The principal sterols isolated fromE. ferox were 24‐ethylcholest‐5‐en‐3β‐ol (46%) and 24(R)‐methylcholesta‐5,22‐dien‐3β‐ol (14%).
Effect of pH on the affinity of phospholipids for cholesterol
Authors: Jacobsohn Myra K. , Bazilian Linda S. , Hardiman Janice , Jacobsohn Gert M. 
Published: November 2006

AbstractThe ability of multilamellar vesicles of phosphatidylcholine and phosphatidylethanolamine in aqueous phase to prevent access to cholesterol by a nonpolar solvent was examined. Phosphatidylethanolamine vesicles retained less sterol than phosphatidylcholine vesicles. In mixed vesicles, cholesterol was retained in proportion to the amount of phosphatidylcholine. To alter the charge and hydration of head groups, pH was adjusted from 1.2 to 12.5. Above pH 8, both phosphatidylethanolamine and phosphatidylcholine retained sterol in a 1∶1 molar ratio of phospholipid to cholesterol, regardless of acyl side chain composition. Between pH 2.0 and pH 8.0, sterol retention varied with type of head group and side chain. Lipids with 16‐carbon saturated side chains retained more sterol than 18‐carbon unsaturated or 12‐carbon saturated side chains. Between pH 1.1 and 2.0, none of the phosphatidylethanolamines retained sterol, but long chain phosphatidylcholines, saturated or unsaturated, retained sterol in a 1∶1 molar ratio of phospholipid to sterol. Short chain phosphatidylethanolamines and phosphatidylcholines retained 0 to 20% at the low‐ to mid‐pH range. Size of multilamellar vesicles, measured by Doppler effect light scattering analysis, had no bearing on sterol retention. Sonication of vesicles, which increases surface curvature, increases the retention of sterol. Fluorescence polarization indicated that cholesterol does not interact with DPPC or DLPC side chains. The observations can be interpreted in terms of space requirements of head groups, including charge repulsion and hydration. Other factors, such as monovalent cation replacement by protons, juxtaposition of charged groups on vesicle surfaces and length and unsaturation of acyl side chains affect the affinity of phospholipids for cholesterol.
Δ6 and Δ5 desaturase activities in liver from obese zucker rats at different ages
Authors: Blond Jean‐Paul , Henchiri Cherifa , Bézard Jean 
Published: November 2006

AbstractΔ6 Desaturation of linoleic acid (18∶2 n−6) and Δ5 desaturation of dihomo‐γ‐linolenic acid (20∶3 n−6) were measured in liver microsomes from genetically obese Zucker rats (fa/fa) and from their lean littermates (Fa/−). Both groups were fed a balanced commercial diet. The rats were 6, 9 and 12 weeks old, which corresponded to stages in their active growth period. The content of total fatty acids and n−6 polyunsaturated fatty acids in whole liver and liver microsomes was also determined in order to ascertain how the desaturase activities measuredin vitro reflected regulation of essential fatty acid metabolismin vivo. Contrary to values obtained for Δ6 desaturation, Δ5 desaturation at nonsaturating substrate levels were lower in obese rats than in lean controls. In contrast, at saturating substrate level, the maximal Δ5 desaturase activities were the same in both phenotypes and they increased with age. Study of Δ5 desaturation kinetics (1/V vs 1/S) showed that Vm did not differ between 12‐week‐old obese and lean rats, whereas KM in obese rats was much lower than in controls, expressing the very low affinity of the enzyme for the substrate in obese animals. The fatty acid composition of liver lipids reflected the results of desaturase activitiesin vitro. In particular, the ratios 20∶4 n−6/20∶3 n−6 were lower in obese rats than in lean rats, which can be explained by the lower conversion of 20∶3 n−6 into 20∶4 n−6 by Δ5 desaturation. However, the total amount of 20∶4 n−6 in the whole liver did not differ between phenotypes, whatever their age. This work presents evidence for a relationship between the changes in fatty acid compositional data in hepatic total lipids, total lipids of liver microsomes and modifications of fatty acid desaturase activities in the genetically obese Zucker rat.
Molecular species of glycerophospholipids and sphingomyelins of human plasma: Comparison to red blood cells
Authors: Myher J. J. , Kuksis A. , Pind S. 
Published: November 2006

AbstractIn addition to diacyl glycerophosphocholine and sphingomyelin, human plasma also contains small amounts of other glycerophospholipids, which may have special metabolic function. The structure and origin of these minor plasma lipids has not been determined. Knowledge of the detailed composition of the phospholipids of red blood cells (Myheret al., Lipids 24, 1989) permits evaluation of one of the possible sources. This study reports the detailed analyses of plasma glycerophospholipids made in parallel to those of the erythrocyte lipids obtained from the same blood using HPLC and GLC methods. The proportions of the major phospholipid classes in the plasma and erythrocytes were similar to published values, including the essential absence of diradyl glycerophosphoserine from plasma. Plasma diradyl glycerophosphocholine contained 93.0% diacyl, 3.4% alkylkacyl and 3.6% alkenylacyl, whereas the diradyl glycerophosphoethanolamine consisted of 71.8% alkenylacyl, 19.9% diacyl and 8.3% alkylacyl subclasses. The diradyl glycerophosphoinositol was 100% diacyl. The content of the minor subclasses of plasma diradyl glycerophosphocholine is similar to that of the red cells, but the ether content of the diradyl glycerophosphoethanolamine is higher in plasma than in cells. The lipid ether subclasses of plasma glycerophospholipids also contained a higher proportion of the C20, C22 and C24 alkyl and alkenyl chains than those of the cells. Furthermore, the C16 and C18‐containing species in diradyl glycerophosphoethanolamine subclasses varied with the nature of the polyunsaturated acid, whereas in diradyl glycerophosphocholine subclasses the polyunsaturated acids were combined with the C16 and C18 acids in equal proportions. The significant differences in the molecular species of glycerophospholipids and sphingomyelin between plasma and red cells would appear to limit any direct transfer or equilibration of their lipid components.
Modulating influence of dietary lipid intake on the prostaglandin system in adult men
Authors: Ferretti Aldo , Judd Joseph T. , Taylor Philip R. , Schatzkin Arthur , Brown C. 
Published: November 2006

AbstractWe evaluated the effect of moderate dietary changes on the prostaglandin system by measuring the urinary excretion of 7α‐hydroxy‐5,11‐dioxo‐tetranorprostane‐1,16‐dioic acid (PGE‐M). In a crossover design, twenty‐four free‐living male subjects in good health (24 to 54 years of age) were fed two diets: (i) Regular (R) diet, 41% energy (en%) from fat, P/S 0.59, M/S 0.96; (ii) Experimental (E) diet, 19 en% from fat, P/S 1.31, M/S 1.48. Diet R contained 13.9 g/day of neutral detergent fiber (NDF) and about 600 mg/day of cholesterol per 3200 kcal; Diet E contained 35.5 g/day NDF and about 280 mg/day cholesterol. Each controlled‐diet period lasted ten weeks. The menu cycle was 7 days, and all diets were calculated to provide adequate amounts of essential nutrients. The PGE‐M excretion rates were determined in 24‐hr urine by stable‐isotope dilution gas chromatography‐mass spectrometry in the selected ion‐monitoring mode. Low‐fat Diet E, with an intake of 6.6 en% from polyunsaturates, was associated with an average 14.2% reduction in PGE‐M daily output, compared to high‐fat Diet R with a 9.3 en% from polyunsaturates (P=0.046). These results support the view that dietary lipid changes can significantly alter thein vivo production of E‐series prostaglandins. We cannot conclude, however, if this apparent diet effect was brought about by the change in linoleate intake alone or was the result of complex biochemical interactions among individual fatty acids, both saturated and unsaturated.
Synthesis and lipase catalyzed hydrolysis of thiolesters of 2‐, 3‐ and 4‐methyl octanoic acids
Authors: Sonnet Philip E. , Baillargeon Mary Welch 
Published: November 2006

AbstractRacemic 2‐, 3‐ and 4‐methyloctanoic acids were synthesized. The 2‐mercaptoethanol S‐esters of these branched acids, and of octanoic acid, were exposed to lipases of the fungiCandida rugosa andAspergillus niger. Reactions were followed spectrophotometrically using Ellman's Reagent. Branching at the 3‐position retards lipolysis more severely than at either the 2‐ or 4‐positions. Features of the assay method are discussed with reference to titrimetry.
Lipids and fatty acids of the horseshoe crabsTachypleus gigas andCarcinoscorpius rotundicauda
Authors: Pakrashi Satyesh C. , Duffa Pradeep K. , Achari Basudeb , Misra Suniti , Choudhury Amalesh , Chattopadhyay Subhashis , Ghosh Amitabha 
Published: November 2006

AbstractTotal lipids from hepatopancreas of the horseshoe crabs,Tachypleus gigas andCarcinoscorpius rotundicauda, obtained in 7.6 and 3.3% wet weight respective yields, were fractionated by various chromatographic techniques and identified by gas‐liquid chromatography and spectroscopic methods. Fatty acid‐containing lipids were rich in 16∶0 (8.0–25%), 18∶1ω9 (6.9–22%) and 18∶2ω6 (6.8–18.5%); appreciable amounts of 16∶1ω7, 18∶3ω3, 20∶5ω3 and 22∶6ω3 were also present. The level of 26∶0 in the hydrocarbon fractions was unusually high (64 and 68%). Carbon chain lengths of major wax esters were 44, 46 and 48 forT. gigas and 38, 40 and 42 forC. rotundicauda. 1‐O‐Alkyl diglycerides were 7.2 and 9.1% of the total lipids in the two species and contained 14∶0(20%), 16∶0(60%) and 18∶0(20%) alkyl chains along with a relatively higher percentage (32–35%) of saturated fatty acids. High levels of cholesterol (>50% of total sterol) in the free and combined state were encountered in both samples, phospholipid contents being 40 and 35%, respectively, and contained highest levels of unsaturated fatty acids.
Black currant seed oil feeding and fatty acids in liver lipid classes of guinea pigs
Authors: Crozier G. L. , Fleith M. , Traitler H. , Finot P. A. 
Published: November 2006

AbstractGuinea pigs were fed one of three diets containing 10% black currant seed oil (a source of gamma‐linolenic (18∶3 n−6) and stearidonic (18∶4 n−3) acids), walnut oil or lard for 40 days. The fatty acid composition of liver triglycerides, free fatty acids, cholesteryl esters, phosphatidylinositol, phosphatidylserine, cardiolipin, phosphatidylcholine and phosphatidylethanolamine were determined.Dietary n−3 fatty acids found esterified in liver lipids had been desaturated and elongated to longer chain analogues, notably docosapentaenoic acid (22∶5 n−3) and docosahexaenoic acid (22∶6 n−3). When the diet contained low amounts of n−6 fatty acids, proportionately more of the n−3 fatty acids were transformed. Significantly more eicosapentaenoic acid (EPA) (20∶5 n−3) was incorporated into triglycerides, cholesteryl esters, phosphatidylcholine and phosphatidylethanolamine of the black currant seed oil group compared with the walnut oil group.Feeding black currant seed oil resulted in significant increases of dihomogamma‐linolenic acid (20∶3 n−6) in all liver lipid classes examined, whereas the levels of arachidonic acid (20∶4 n−6) remained relatively stable. The ratio dihomo‐gamma‐linolenic acid/arachidonic acid was significantly (2.5‐fold in PI to 17‐fold in cholesteryl esters) higher in all lipid classes from the black currant seed oil fed group.
Three new and bioactive icosanoids from the temperate red marine algaFarlowia mollis
Authors: Solem Michele L. , Jiang Zhi D. , Gerwick William H. 
Published: November 2006

AbstractThree new dihydroxyicosanoids, 12(R),13(R)‐dihydroxyicosa‐5(Z), 8(Z),10(E),14(Z)‐tetraenoic acid, 12(R),13(R)‐dihydroxyicosa‐5(Z), 8(Z),10(E),10(Z),17(Z)‐pentaenoic acid and 10(R*),11(R*)‐dihydroxyoctadeca‐6(Z),8(E),12(Z)‐trienoic acid, have been isolated from a previously unstudied temperate red marine alga,Farlowia mollis (Cryptonemiales, Rhodophyta). The structures of these new metabolites have been deduced from detailed nuclear magnetic resonance and mass spectrometry analyses on stabilized diacetate‐methyl esters and stereochemistry deduced by1H NMR couplings and CD analysis of a dibenzoate derivative. Collectively, these new natural products modulate fMLP‐induced superoxide anion generation in human neutrophils, inhibit the conversion of arachidonic acid to lipoxygenase products by human neutrophils, and inhibit the functioning of the dog kidney Na+/K+ ATPase.
Fish oil prevents change in arachidonic acid and cholesterol content in rat caused by dietary cholesterol
Authors: Garg M. L. , Wierzbicki A. , Keelan M. , Thomson A. B. R. , Clandinin M. T. 
Published: November 2006

AbstractRats were fed diets high in either saturated fat (beef tallow) or α‐linolenic acid (linseed oil) or eicosapentaenoic and docosahexaenoic acids (fish oil) with or without 2% cholesterol supplementation. Consumption of linseed oil and fish oil diets for 28 days lowered arachidonic acid content of plasma, liver and heart phospholipids. Addition of 2% cholesterol to diets containing beef tallow or linseed oil lowered 20∶4ω6 levels but failed to reduce 20∶4ω6 levels when fed in combination with fish oil. Feeding ω3 fatty acids lowered plasma cholesterol levels. Addition of 2% cholesterol to the beef tallow or linseed oil diet increased plasma cholesterol concentrations but not when fish oil was fed. Feeding the fish oil diet reduced the cholesterol content of liver, whereas feeding the linseed oil diet did not. Dietary cholesterol supplementation elevated the cholesterol concentration in liver in the order: linseed oil > beef tallow > fish oil (8.6‐, 5.5‐, 2.6‐fold, respectively). Feeding fish oil and cholesterol apparently reduced 20∶4ω6 levels in plasma and tissue lipids. Fish oil accentuates the 20∶4ω6 lowering effect of dietary cholesterol and appears to prevent accumulation of cholesterol in plasma and tissue lipids under a high dietary load of cholesterol.
Developmental regulation of sterol biosynthesis inCucurbita maxima L.
Authors: Fenner Gregeory P. , Patterson Glenn W. , Lusby William R. 
Published: November 2006

AbstractTwenty‐two sterols were identified by capillary gas chromatography and capillary gas chromatography/mass spectroscopy inCucurbita maxima grown under green‐house conditions. Both whole plants and individual tissues (leaves, stems, roots, cotyledons, flowers) were analyzed at weekly intervals during the 12‐week development of the plant. In whole plants, sterol accumulation parallels plant growth except for a period in the mid‐life cycle where there is a reduction in the amount of sterol accumulated on a total sterol/plant and mg sterol/g dry wt basis. This reduction in the amount of sterol is coincident with the visual onset of flowering. During development, the percent contribution of each class of sterol (Δ5_, Δ7_, Δ0_‐sterols) remains relatively constant. However, the percent contribution of an individual sterol species varies depending on the tissue examined and the developmental period selected for analysis. While the young plant (<2 weeks) possesses elevated levels of sterols with the Δ25(27)‐double bond, the trend was toward a reduction in the amounts of these sterols with development. Leaves and stems accumulate large quantities of 24ζ‐ethyl‐5α‐cholesta‐7,22‐dien‐3β‐ol (7,22‐stigmastadienol) and 24ζ‐ethyl‐5α‐cholest‐7‐en‐3β‐ol (7‐stigmastenol), while roots accumulate only 7,22‐stigmastadienol as their principal sterol. Male flowers and roots were found to contain elevated levels of Δ5_‐sterols.
Effects of dietary n−3 polyunsaturated fatty acids on phospholipid composition and calcium transport in mouse cardiac sarcoplasmic reticulum
Authors: Croset M. , Black J. M. , Swanson J. E. , Kinsella J. E. 
Published: November 2006

AbstractThe effects of dietary n−3 and n−6 polyunsaturated fatty acids on the fatty acid composition of phospholipid, Ca++· Mg++ ATPase and Ca++ transport activities of mouse sarcoplasmic reticulum were investigated. Mice were fed a 2 weight percent fat diet containing either 0.5 weight percent ethyl esters of 18∶3n−3, 20∶5n−3 or 22∶6n−3 as a source of n−3 polyusaturated fatty acid or 0.5 weight percent safflower oil as a cource of n−6 polyunsaturated fatty acid for 10 days. Olive oil (2 weight percent) was used as a control diet. Although feeding n−6 polyunsaturated fatty acid induced very little modifications of the phospholipid sarcoplasmic reticulum fatty acid composition, feeding n−3 polyunsaturated fatty acid altered it markedly. Inclusion of 18∶−3, 20∶5n−3 or 22∶6n−3 in the diet caused an accumulation of 22∶6n−3, which replaced 20∶4n−6 and 18∶2n−6 in phospholipid sarcoplasmic reticulum. The saturated fatty acids were significantly increased with a concurrent reduction of 18∶1n−9. These changes in the fatty acid composition resulted in a decrease in the values of the n−6/n−3 polyunsaturated fatty acid ratio and a decrease in the ratio of 20 carbon to 22 carbon fatty acids esterified in the phospholipid sarcoplasmic reticulum. This was associated with a decrease in Ca++ uptake by n−3 polyunsaturated fatty acid enriched sarcoplasmic reticulum vesicles as compared with n−6 fatty acid and control diet sarcoplasmic reticulum vesicles. However, neither the affinity for Ca++ nor the maximal velocity of ATP hydrolysis activity of Ca++·MG++ ATPase were altered by the different diets. The data suggest that the incorporation of 22∶6n−3 and/or the decrease of 20∶4n−6 plus 18∶2n−6 in the phospholipid sarcoplasmic reticulum may affect the membrane lipid bilayer structure and make it more permeable to Ca++.
Skeletal lipid depletion in spawning salmon
Authors: Phleger C. F. , Laub R. J. , Benson A. A. 
Published: November 2006

AbstractSkeletal tissues in Pacific salmon are composed of significant amounts of lipid (which serves as an energy supply), that is then depleted during migration and freshwater spawning. The vertebral centra and neurocrania of ocean prespawning pink salmonOncorhynchus gorbuscha, although composed respectively of 2.9–13% and 0.5–6.3% lipid (each by dry weight), amount only to 0–1.6% and 0–1.4% in river postspawning individuals. The skeletal lipids are 91–98% triacylglycerol with only small amounts of phospholipid and cholesterol. Triacylglycerols of carbon numbers 47, 49 and 51 are selectively depleted during spawning, whereas there are increases in the relative amounts of those of carbon numbers 55, 57, 59 and 61. The patterns of variation of the skeletal lipids of coho salmon,O. kisutch, chum salmon,O. keta, and sockeye salmon,O. nerka are similar to those ofO. gorbuscha.
Effects of dietary fish oil on human mammary carcinoma and on lipid‐metabolizing enzymes
Authors: Borgeson Charlotte E. , Pardini Lani , Pardini Ronald S. , Reitz Ronald C. 
Published: November 2006

AbstractThe growth rate of a human mammary carcinoma, MX‐1, was significantly reduced in athymic “nude” mice fed fish oil. Tumors from the fish oil‐fed animals also showed a greater sensitivity to two anti‐neoplastic agents, mitomycin C and doxorubicin. Mitochondria were isolated from control livers, host livers and tumors from fish oil‐and corn oil‐fed animals, and increased levels of 20∶5n−3 and 22∶6n−3 were found in mitochondrial lipids in all three tissues from the fish oil‐fed animals. To investigate the effect of dietary n−3 fatty acids on lipid metabolism, the activity of the acyl‐CoA:carnitine acyltransferase and three acyl‐CoA desaturases were measured. Carnitine acyltransferase activity toward all four acyl‐CoA substrates tested was markedly increased in mitochondria from liver by feeding fish oil. In mitochondria from tumors, feeding fish oil resulted in an increased activity toward only 18∶3n−3. These data suggest that fish oil may induce an increase in the oxidation of fatty acids. The Δ9‐desaturase activity was decreased in microsomes from liver and tumor from fish oil‐fed animals. However, both the Δ6 and Δ5 desaturases were increased in tumor and in control liver as a result of feeding fish oil. The Δ5 desaturase was not altered in microsomes from the host animals. The effect of fish oil on the Δ5 and Δ6 desaturases may involve alterations to metabolism of specific polyunsaturated fatty acids especially in the tumor tissue.
The common occurrence of furan fatty acids in plants
Authors: Hannemann Kerstin , Puchta Volker , Simon Ernst , Ziegler Herta , Ziegler Gunter , Spiteller Gerhard 
Published: November 2006

AbstractThe observation that F‐acids (1) occur in rat chow initiated a search for F‐acids in human diet. We observed that the amount of F‐acids with a pentyl side chain in α‐position taken up with a one‐day diet correlates well with the amount of excreted degradation products, the pentyl urofuran acids (2), (3) and (4). Therefore it can be concluded that F‐acids with a pentyl side chain are not produced in the human body but are introduced through the diet. The origin of F‐acids carrying an α‐propyl side chain is less clear. The amount of propyl‐urofuran acids (2) and (3) excreted in urine was found in one case out of three to be five times higher than the amount of F‐acids carrying a propyl group in α‐position taken up by the diet. Therefore, it can presently not be excluded that a portion of the propyl F‐acids is produced by the body.F‐acids found in human food are mainly introduced into the body by vegetables and fruits. F‐acids were found also in birch leaves in considerable amounts, as well as in grasses, dandelion and clover leaves. Thus, we can conclude that F‐acids are common constituents of plants.
Modulation of eicosanoid production and cell‐mediated cytotoxicity by dietary α‐linolenic acid in BALB/c mice
Authors: Fritsche Kevin L. , Johnston Patricia V. 
Published: November 2006

AbstractThe effects of dietary α‐linolenic acid (18∶3n−3) on fatty acid composition, eicosanoid production, and cell‐mediated cytotoxic activity of immune cells before and after challenge with virus or poly I‐C from BALB/c mice were studied. Weanling BALB/c mice were fed purified diets containing either 10%‐by‐weight corn oil or linseed oil providing a ratio of 18∶3n−3 to 18∶2n−6 of 1/32 or 2/1, respectively, for 6–10 weeks. Fatty acid analysis of splenocyte phospholipids showed an appreciable increase in the percentage of n−3, and a decrease in n−6, fatty acids in splenocytes from mice fed the linseed oil diet. Splenocyte prostaglandin E and peritoneal exudate cell leukotriene C production was significantly lower in the linseed oilfed mice. In general, cell‐mediated cytotoxic activity was similar for immune cells from linseed oil and corn oil‐fed mice. However, 6 days after the viral challenge, splenocyte cell‐mediated cytotoxic activity was significantly higher in linseed oil mice. This higher activity was associated with nonspecific cytotoxicity rather than that of viral‐specific cytotoxic T‐lymphocytes. Cell yields from the spleen and peritoneum were frequently significantly higher in linseed oil mice. Interactions between dietary 18∶3n−3, eicosanoid production, and immune cell proliferation and/or migration are discussed. In summary, feeding mice a diet rich in 18∶3n−3 elevates immune cell n−3 fatty acid content, reduces eicosanoid synthesis and, to a limited extent, enhances the cell‐mediated cytotoxic response to a viral challenge.