bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved separation of conjugated fatty acid methyl esters by silver ion‐high‐performance liquid chromatography
Authors: Sehat Najibullah , Rickert Rainer , Mossoba Magdi M. , Kramer John K. G. , Yurawecz Martin P. , Roach John A. G. , Adlof Richard O. , Morehouse Kim M. , Fritsche Jan , Eulitz Klaus D. , Steinhart Hans , Ku Yuoh 
Published: November 2006

AbstractOperating from one to six silver ion‐high‐performance liquid chromatography (Ag+‐HPLC) columns in series progressively improved the resolution of the methyl esters of conjugated linoleic acid (CLA) isomeric mixtures from natural and commercial products. In natural products, the 8 trans, 10 cis‐octadecadienoic (18∶2) acid was resolved from the more abundant 7 trans, 9 cis‐18∶2, and the 10 trans, 12 cis‐18∶2 was separated from the major 9 cis, 11 trans‐18∶2 peak. In addition, both 11 trans, 13 cis‐18∶2 and 11 cis, 13 trans‐18∶2 isomers were found in natural products and were separated; the presence of the latter, 11 cis, 13 trans‐18∶2, was established in commercial CLA preparations. Three Ag+‐HPLC columns in series appeared to be the best compromise to obtain satisfactory resolution of most CLA isomers found in natural products. A single Ag+‐HPLC column in series with one of several normal‐phase columns did not improve the resolution of CLA isomers as compared to that of the former alone. The 20∶2 conjugated fatty acid isomers 11 cis, 13 trans‐20∶2 and 12 trans, 14 cis‐20∶2, which were synthesized by alkali isomerization from 11 cis, 14 cis‐20∶2, eluted in the same region of the Ag+‐HPLC chromatogram just before the corresponding geometric CLA isomers. Therefore, CLA isomers will require isolation based on chain length prior to Ag+‐HPLC separation. The positions of conjugated double bonds in 20∶2 and 18∶2 isomers were established by gas chromatography‐electron ionization mass spectrometry as their 4,4‐dimethyloxazoline derivatives. The double‐bond geometry was determined by gas chromatography‐direct deposition‐Fourier transform infrared spectroscopy and by the Ag+‐HPLC relative elution order.
Fatty acid metabolism in marine fish: Low activity of fatty acyl Δ5 desaturation in gilthead sea bream (Sparus aurata) cells
Authors: Tocher Douglas R. , Ghioni Cristina 
Published: November 2006

AbstractMarine fish have an absolute dietary requirement for C20and C22highly unsaturated fatty acids. Previous studies using cultured cell lines indicated that underlying this requirement in marine fish was either a deficiency in fatty acyl Δ5 desaturase or C18–20elongase activity. Recent research in turbot cells found low C18–20elongase but high Δ5 desaturase activity. In the present study, the fatty acid desaturase/elongase pathway was investigated in a cell line (SAF‐1) from another carnivorous marine fish, sea bream. The metabolic conversions of a range of radiolabeled polyunsaturated fatty acids that comprised the direct substrates for Δ6 desaturase ([1‐14C]18∶2n−6 and [1‐14C]18∶3n−3), C18–20elongase ([U‐14C]18∶4n−3), Δ5 desaturase ([1‐14C]20∶3n−6 and [1‐14C]20∶5n−3), and C20–22elongase ([1‐14C]20∶4n−6 and [1‐14C]20∶5n−3) were utilized. The results showed that fatty acyl Δ6 desaturase in SAF‐1 cells was highly active and that C18–20elongase and C20–22elongase activities were substantial. A deficiency in the desaturation/elongation pathway was clearly identified at the level of the fatty acyl Δ5 desaturase, which was very low, particularly with 20∶4n−3 as substrate. In comparison, the apparent activities of Δ6 desaturase, C18–20elongase, and C20–22elongase were approximately 94‐, 27‐, and 16‐fold greater than that for Δ5 desaturase toward their respective n−3 polyunsaturated fatty acid substrates. The evidence obtained in the SAF‐1 cell line is consistent with the dietary requirement for C20and C22highly unsaturated fatty acids in the marine fish the sea bream, being primarily due to a deficiency in fatty acid Δ5 desaturase activity.
Screening of lipase inhibitors from marine algae
Authors: Bitou Nozomu , Ninomiya Masayori , Tsujita Takahiro , Okuda Hiromichi 
Published: November 2006

AbstractThe possible presence of an inhibitor of pancreatic lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was screened in 54 marine algae. An active inhibitor, caulerpenyne, was purified from an extract of Caulerpa taxifolia, using ethyl acetate extraction, followed by successive chromatographies on ODS and silica gel columns. The purified inhibitor was identified by thin‐layer chromatography, infrared and nuclear magnetic resonance spectroscopy. Caulerpenyne competitively inhibited lipase activities using emulsified triolein and dispersed 4‐methylumbelliferyl oleate (4‐MU oleate) as substrates. The concentrations producing 50% inhibition against triolein and 4‐MU oleate hydrolysis were 2 mM and 13 μM, respectively. In vivo, oral administration of corn oil with or without caulerpenyne to rats demonstrated a reduced and delayed peak plasma triacylglycerol concentration with caulerpenyne.
Cross‐influence of membrane polyunsaturated fatty acids and hypoxia‐reoxygenation on α‐ and β‐adrenergic function of rat cardiomyocytes
Authors: Ponsard Blandine , Durot Isabelle , Delerive Philippe , Oudot Fabien , Cordelet Catherine , Grynberg Alain , Athias Pierre 
Published: November 2006

AbstractThe purpose of the present investigation was to determine whether the beneficial effects of polyunsaturated fatty acids (PUFA) may influence ischemia‐reperfusion‐induced alterations of myocardial α‐ and β‐adrenoceptor (α‐AR, β‐AR) responsiveness. This study was carried out using monolayer cultures of neonatal rat ventricular myocytes in a substrate‐free, hypoxia‐reoxygenation model of ischemia. The cardiomyocytes (CM) were incubated during 4 days in media enriched either with n−6 PUFA (arachidonic acid, AA) or with n−3 PUFA (eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA). The n−6/n−3 ratio in n−3 CM was close to 1.2, compared to 20.1 in n−6 CM. The contractile parameters of n−6 CM and n−3 CM were similar in basal conditions as well as during hypoxia and reoxygenation. In basal conditions, the phospholipid (PL) enrichment with long chain n−3 PUFA resulted in an increased chronotropic response to isoproterenol (ISO) and to phenylephrine (PHE). After posthypoxic reoxygenation, the chronotropic response to β‐AR activation in n−6 CM was significantly enhanced as compared with the control response in normoxia. In opposition, the ISO‐induced rise in frequency in n−3 CM in control normoxia and after reoxygenation was similar. In these n−3 CM, the changes in contractile parameters, which accompanied the chronotropic response, were also similar in reoxygenation and in normoxic periods, although the rise in shortening velocity was slightly increased after reoxygenation. In response to PHE addition, only the chronotropic effect of n−6 CM appeared significantly enhanced after hypoxic treatment. These results suggested that increasing n−3 PUFA in PL reduced the increase in α‐ and β‐AR functional responses observed after hypoxia‐reoxygenation. This effect may partly account for the assumed cardiac protective effect of n−3 PUFA, through the attenuation of the functional response to catecholamines in the ischemic myocardium.
Effects of dietary supplementation of saturated fatty acids and of n−6 or n−3 polyunsaturated fatty acids on plasma and red blood cell membrane phospholipids and deformability in weanling guinea pigs
Authors: Pöschl Johannes M. B. , Paul Karl , Leichsenring Michael , Han Shan R. , Pfisterer Matthias , Bremer Hans J. , Linderkamp Otwin 
Published: November 2006

AbstractThe fatty acid composition of plasma cholesteryl esters, plasma phospholipids, red blood cell (RBC) membrane phosphatidylcholine (corresponding to the outer membrane leaflet), and phosphatidylethanolamine (corresponding to the inner membrane leaflet) was investigated in weanling guinea pigs fed with diets of cacao (saturated fatty acids), sunflower oil [n−6 polyunsaturated fatty acids (PUFA)] or fish oil (n−3 PUFA) for 20 wk. RBC deformation was measured by means of a cell‐transit analyzer (filtration) and a cone‐plate rheoscope. The contents of saturated fatty acids in plasma phospholipids and RBC membrane leaflets were similar in all three groups. Diets with sunflower oil resulted in a high content of linoleic acid in plasma cholesteryl esters and in the outer leaflet of RBC membranes. Fatty acids of fish oil were mainly incorporated in plasma phospholipids and in the inner leaflet of RBC membranes. The arachidonic acid content was high in all groups in the plasma phospholipids and in the inner leaflet. The n−6 and n−3 PUFA were mainly incorporated in the inner leaflet. In all groups the polyunsaturated/saturated fatty acid ratio and the total PUFA content were similar in the inner RBC membrane. The RBC filtration times and the RBC deformation indices were not affected by the dietary treatment.
Dietary supplementation with arachidonic and docosahexaenoic acids has no effect on pulmonary surfactant in artificially reared infant rats
Authors: Yeh Yu‐Yan , Whitelock Kerry Anne , Yeh Shaw‐Mei , Lien Eric L. 
Published: November 2006

AbstractDespite the potential use of long‐chain polyunsaturated fatty acid (LCPUFA) supplementation to promote growth and neural development of the infant, little is known about potential harmful effects of the supplementation. The present study determined whether supplementation with arachidonic acid (AA) and/or docosahexaenoic acid (DHA) in rat milk formula (RMF) affects saturation of pulmonary surfactant phospholipids (PL). Beginning at 7 d of age, infant rats were artificially fed for 10 d with RMF supplemented with AA at 0, 0.5, and 1.0% of total fatty acid, or supplemented with DHA at 0, 0.5, and 1.0%, or cosupplemented with AA and DHA at levels of 0∶0, 0.5∶0.3, and 1.0∶0.6% of the fat blend. Lung tissue PL contained 43 weight percent palmitate (16∶0) of total fatty acids in infant rats fed the unsupplemented RMF. The supplementation with AA at both 0.5 and 1.0% decreased the weight percentage of 16∶0 and stearate (18∶0), indicating a decrease in saturation of PL. The observed decreases were accompanied by increases in AA and linoleic acid (18∶2n−6). Surfactant phosphatidylcholine (PC) consisted of 71 weight percent 16∶0 in the unsupplemented group, and this highly saturated PC was not altered by the cosupplementation with AA and DHA although there was a slight increase in DHA. Similarly, the cosupplementation did not change fatty acid composition of surfactant PL when compared with the unsupplemented group. The cosupplementation slightly decreased the weight percentage of 16∶0 with a proportional increase in 18∶0 leading to an unchanged weight percentage of total saturated fatty acids. These results suggest that, unlike lung tissue PL, the composition of saturated fatty acids in surfactant PL, particularly PC, is resistant to change by dietary AA and DHA supplementation. This, together with the unchanged concentration of total fatty acids in surfactant PC, indicates that LCPUFA cosupplementation causes no effect on pulmonary surfactant.
Lipophilic aldehydes and related carbonyl compounds in rat and human urine
Authors: Kim Song‐Suk , Gallaher Daniel D. , Csallany A. Saari 
Published: November 2006

AbstractRat and human urine samples were analyzed for lipophilic aldehydes and other carbonyl products of lipid peroxidation. The following compounds were identified as their 2,4‐dinitrophenyl hydrazones by cochromatography with pure standards using three solvent systems: butanal, butan‐2‐one, pentan‐2‐one, hex‐2‐enal, hexanal, hepta‐2,4‐dienal, hept‐2‐enal, octanal, non‐2‐enal, deca‐2,4‐dienal, 4‐hydroxyhex‐2‐enal, and 4‐hydroxynon‐2‐enal. In general, fasted rats excreted less of these compounds than fed rats, indicating they were partially of dietary origin or that the endogenous compounds were excreted in a form not susceptible to hydrazone formation. The compounds excreted in human urine were similar to those excreted in rat urine but were present in lower concentrations. Identification of the conjugated forms fo the lipophilic aldehydes and related carbonyl compounds excreted in urine may be a source of information about their reactions in vivo.
Fenofibrate protects lipoproteins from lipid peroxidation: Synergistic interaction with α‐tocopherol
Authors: Chaput Evelyne , Maubrou‐Sanchez Dominique , Bellamy François D. , Edgar Alan D. 
Published: November 2006

AbstractOne of the earliest steps of atherosclerotic plaque formation is an increase of circulating apolipoprotein B‐containing lipoproteins which, after infiltrating the subendothelial space, undergo oxidative modification. Fenofibrate is an effective cholesterol‐ and triglyceride‐lowering agent which has been shown to be beneficial in the treatment of atherosclerosis. Vitamin E, or α‐tocopherol, is a powerful antioxidant which has been shown in a variety of studies to prevent lipoprotein peroxidation. The purpose of the present study was to investigate the effect of fenofibrate treatment, either alone or in combination with α‐tocopherol, in reducing the susceptibility of lipoproteins to oxidative modification. Rats fed a normal diet were treated for up to 27 d with fenofibrate, either alone or in combination with equimolar doses of α‐tocopherol. Combined VLDL (very low density lipoproteins) and LDL (low density lipoproteins) isolated after fenofibrate treatment were more resistant to coppermediated oxidation, as assessed by conjugated diene formation. Lag time was prolonged up to 3.2‐fold, while the maximal rate of diene production was significantly decreased by up to 2.2‐fold. Treatment of rats with α‐tocopherol alone at the selected dose had no significant effect on lag time, while the propagation rate was slightly decreased. Coadministration of fenofibrate with α‐tocopherol prolonged the lag phase to a greater extent than fenofibrate alone, showing a synergistic interaction between the two compounds. Finally, the combination of fenofibrate and α‐tocopherol was significantly more effective in modifying lipoprotein oxidation parameters than what was observed with α‐tocopherol and bezafibrate or gemfibrozil. Thus, in addition to its well‐established effects on lipoprotein concentrations and atherogenic parameters, fenofibrate reduces the susceptibility of VLDL and LDL to oxidative modification and exerts its action synergistically with α‐tocopherol.
Microemulsion of seal oil markedly enhances the transfer of a hydrophobic radiopharmaceutical into acetylated low density lipoprotein
Authors: Xiao Wu , Wang Lili , Davis Philip J. , Liu Hu 
Published: November 2006

AbstractFour different microemulsions differing in their core lipid component (triolein, canola oil, squalene, or seal oil) and containing 1,3‐dihydroxypropan‐2‐one 1,3‐diiopanoate (DPIP), a potential radioimaging probe, were prepared by means of ultrasonication. The DPIP microemulsions were incubated with acetylated human low density lipoprotein (AcLDL) and the amount of DPIP transferred into AcLDL was examined. The amount of DPIP in the microemulsions expressed as DPIP/oil (w/w) was dependent on the core lipid component of the microemulsion in the order of seal oil (0.19±0.04, mean ±standard deviation) > squalene (0.15±0.02) > canola oil (0.12±0.02) > triolein (0.07±0.004). With the exception of canola oil, all microemulsions were effective in enhancing the transfer of DPIP into Acl DI in comparison with commonly used methods, i.e, direct diffusion and detergent solubilization. DPIP in seal oil resulted in the highest amount of DPIP transferred into AcLDL [309.16±34.82 vs. 203.19±64.51 using squalene and 151.31±28.54 using triolein (DPIP molecules per AcLDL particle)]. For the first time, oil from harp seals, was studied as a major core lipid component of formulating pharmaceutical microemulsions. DPIP in seal oil resulted in the highest transfer of DPIP into AcLDL which is likely due to the highest DPIP concentration found in this microemulsion as well as the high fluidity of seal oil.
Steryl esters in the elaioplasts of the tapetum in developing Brassica anthers and their recovery on the pollen surface
Authors: Wu Sherry S. H. , Moreau Robert A. , Whitaker Bruce D. , Huang Anthony H. C. 
Published: November 2006

AbstractThe tapetum cells in the developing anthers of Brassica napus contained abundant elaioplasts, which had few thylakoid membranes but were packed with globuli of neutral esters. Of the neutral esters, the major ester group possessed mainly 24‐methylenecholesterol, 31‐norcycloartenol, 24‐dehydropollinastanol, and pollinastanol esterified to 18∶3 and other unsaturated and saturated fatty‐acyl moieties. The minor ester group had a dominant component tentatively identified as 12‐dehydrolupeol esterified to mostly 18∶0, 16∶0, and 20∶0 fatty‐acyl moieties. The elaioplasts also contained a high proportion (16% w/w of total lipids) of monogalactosyldiacylglycerols (MGDG). This is the first report of plastids having steryl esters as the predominant lipids. We propose that the globuli contain steryl esters and are stabilized by surface MGDG and structural proteins. The tapetosomes, the other abundant lipid‐containing organelles in the tapetum, possessed tricylglycerols (TAG) as the predominant lipids. At a late stage of anther development, the minor group of neutral esters and MGDG of the elaioplasts, as well as the TAG of the tapetosomes, were degraded. Steryl esters similar to those of the elaioplasts were recovered from the pollen surface and were the major lipids of the pollen coat. The pollen coat steryl esters and proteins could be extracted with moderately polar or nonpolar solvents. These proteins, which were mostly fragments of oleosins derived from the tapetosomes, had a high proportion of lysine (13 mol %). The possible functions of the steryl esters and the proteins on the pollen surface are discussed.
Occurrence of γ‐linolenic acid in compositae: A study of Youngia tenuicaulis seed oil
Authors: Tsevegsüren Nanzad , Aitzetmüller Kurt , Vosmann Klaus 
Published: November 2006

AbstractSeeds of Youngia tenuicaulis and other species from the plant family Compositae (Asteraceae) were studied for their oil content and fatty acid composition. The seed oil of Y. tenuicaulis growing in Mongolia was found to contain 5.6% γ‐linolenic acid (18∶3Δ6cis,9cis,12cis) in addition to common fatty acids. The oil was analyzed using chromatographic [capillary gas‐liquid chromatography (GLC), thin‐layer chromatography] and spectroscopic (infrared, gas chromatography‐mass spectrometry) techniques. Seed oil fatty acids of Saussurea amara (containing γ‐linolenic acid) and of Arctium minus (containing 18∶3Δ3trans,9cis,12cis), as well as Δ5cis‐ and Δ5trans‐18∶3 were used as GLC reference substances. The evolution in this plant family of a large number of different 18∶3 acids as well as the corresponding evolution of unusual desaturases should be investigated. On the other hand, the Δ6cis‐desaturase required for the biosynthesis of γ‐linolenic acid may have evolved independently several times in unrelated families of the plant kingdom.
High‐fat dairy product consumption increases Δ9c’ 11t−18∶2 (rumenic acid) and total lipid concentrations of human milk
Authors: Park Yongsoon , McGuire Michelle K. , Behr Rebecca , McGuire Mark A. , Evans Marc A. , Shultz Terry D. 
Published: November 2006

AbstractConjugated octadecadienoic acids (18∶2’ conjugated linoleic acids) have been shown to be anticarcinogenic and may influence growth and nutrient partitioning. The Δ9c’ 11t−18∶2 isomer (rumenic acid’ RA) is most common in both food sources and human tissues. To determine if maternal diet can influence milk RA concentration’ breastfeeding women (n=16) were enrolled in a 3‐wk crossover study. Women initially consumed minimal amounts of food containing RA during week 1’ then were assigned randomly to consume diets rich in high‐fat dairy foods (and thus RA) during week 2 or 3. Milk was collected by complete breast expression twice during each experimental week. Current and chronic RA intakes were estimated by 3‐d dietary records and food frequency question‐naires’ respectively. Estimated chronic RA intakes ranged from 49 to 659 mg/d. Dietary RA intake was greater during the high compared to the low dairy period (291±75 vs. 15±24 mg/d’ respectively; P<0.0001). Milk contained more RA during the high than the low dairy period (13.5±0.1 vs. 8.2±0.4 μmol/g lipid’ respectively; P<0.0001). Milk lipid concentration was influenced by diet’ such that lipid concentration was greater during the high than the low dairy period (46.6±5.0 vs. 38.3±1.6 mg/g milk’ respectively; P<0.05). Additionally’ multiple regression analyses suggested that body mass index was the primary predictor of milk RA and lipid concentrations. In summary’ these data indicate that both lipid and RA concentrations of human milk can be influenced by diet.
Elevated plasma levels of F2α isoprostane in cystic fibrosis
Authors: Collins Clare E. , Quaggiotto Paul , Wood Lisa , O'Loughlin Edward V. , Henty Richard L. , Garg Manohar L. 
Published: November 2006

AbstractCystic fibrosis (CT) is associated with chronic lung infection’ inflammation’ and elevated indices of oxidative stress. Recently’ isoprostanes were shown to be a reliable in vivo marker of oxidant injury with 8‐iso‐PGF2α’ shown to cause airflow obstruction and plasma exudation in guinea pig lung. The present study was designed to examine the relationship between 8‐iso‐PGF2α levels’ plasma antioxidants’ and clinical status in CF. We hypothesized that plasma 8‐iso‐PGF2α levels would be higher in subjects with CT compared to healthy controls. Plasma 8‐iso‐PGF2α levels were prospectively measured in 22 subjects with CF and nine healthy controls using an 8‐isoprostane enzyme immunoassay kit along with plasma vitamins A’ E’ and β‐carotene. Plasma 8‐iso‐PGF2α levels were shown to be significantly elevated in the CE subjects compared to controls (319.6±52.6 vs. 145.0±21.0 pg/ml’ P=0.005). Plasma levels of antioxidants were significantly lower for the CF subjects compared to the controls (vitamin A’P<0.003; vitamin E’ P<0.001; and β‐carotene’ P<0.01). This study confirns significantly elevated lipid peroxidation in CF using 8‐iso‐PGF2α levels.
Lymphatic absorption of phytosterol oxides in rats
Authors: Grandgirard André , Sergiel Jean‐Pierre , Nour Mohammed , Demaison‐Meloche Joelle , Gihiès Christian 
Published: November 2006

AbstractTwo of the main classes of oxyphytosterols (7‐keto and epoxides) were synthesized from sitosterol and campesterol and given to mesenteric duct‐cannulated adult male rats. Lymph was collected during 24 h and was analyzed for oxysterols. The results showed that the lymphatic recovery of the phytosterol oxides was low: 4.7% of the given dose for epoxy derivatives and 1.5% for 7‐keto compounds. The campesterol oxides presented a better absorption than the sitosterol oxides. During the process of absorption’ the epoxyphytostanols were also partly transformed in campestanetriol and stigmastanetriol.