bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction of curcumin with human serum albumin—A spectroscopic study
Authors: Pulla Reddy A. Ch , Sudharshan E. , Appu Rao A. G. , Lokesh B. R. 
Published: November 2006

AbstractCurcumin (diferuloyl methane) has a wide range of physiological and pharmacological actions. Curcumin interaction with human serum albumin (HSA) has been followed by fluorescence quenching and circular dichroism (CD) measurements. Based on fluorescence measurements, the equilibrium constant for the interaction is 2.0±0.2×105M−1. Binding of curcumin to HSA induces an extrinsic CD band in the visible region. From the induced CD band measurements, the equilibrium constant has a value of 2.1±0.3×104M−1. Thus, HSA has two kinds of affinity sites for curcumin, one with high affinity and the other with lower affinity. Job's plot indicated a binding stoichiometry of 1∶1 for the high‐affinity site. The equilibrium constant was invariant with temperature in the range of 15 to 45°C, suggesting the role of hydrophobic interactions in the binding of curcumin to HSA. Curcumin does not change the conformation of the HSA molecule. These measurements have implications in the understanding of the curcumin transport under physiological conditions.
Solubilization and stabilization of carotenoids using micelles: Delivery of lycopene to cells in culture
Authors: Xu Xiaoying , Wang Yan , Constantinou Andreas I. , Stacewicz‐Sapuntzakis Maria , Bowen Phyllis E. , van Breemen Richard B. 
Published: November 2006

AbstractThe use of the organic cosolvents tetrahydrofuran and dimethylsulfoxide was found to be unsuitable for prostate tunor cell cultures because of solvent cytotoxicity and the poor solubility and instability of lycopene. For example, the half‐life of lycopene in organic/aqueous solution was found to be less than 2 h. Therefore, a micellar preparation of lycopene was developed for the solubilization and stabilization of lycopene in cell culture media. Neither the micelles themselves nor lycopene solubilized in micelles at concentrations up to 10 μg/mL. in the cell culture media produced cytotoxicity or inhibition of cell proliferation in either LNCaP human prostate cells or Hs888Lu human lung cells. Lycopene solubilized in micelles was stable for at least 96 h under standard cell culture conditions so that a constant lycopene supply could be provided to the cells. During the culture process, lycopene was taken up by LNCaP cells and reached a plateau at approximately 12 h. Micelles provide a convenient, inexpensive, and nontoxic vehicle for dissolving and stabilizing carotenes such as lycopene in tissue culture media and then delivering them to cells growing in culture.
Regulation of mevalonate synthesis in low density lipoprotein receptor knockout mice fed n‐3 or n‐6 polyunsaturated fatty acids
Authors: El‐Sohemy Ahmed , Archer Michael C. 
Published: November 2006

Abstract3‐Hydroxy‐3‐methylglutaryl (HMG)‐CoA reductase, the rate‐limiting enzyme in cholesterol biosynthesis, catalyzes the formation of mevalonate which is also required for cell proliferation. Changes in HMG‐CoA reductase may mediate the differential effects of n‐3 and n‐6 polyunsaturated fatty acids (PUFA) on experimental mammary tumorigenesis, but the mechanisms by which these fatty acids regulate HMG‐CoA reductase are unclear. To determine whether the low density lipoprotein receptor (LDL‐R) is required for this regulation, groups of female LDL‐R knockout (−/−) and wild‐type (+/+) mice were fed 7% fat diets rich in either n‐3 (menhaden oil) or n‐6 (safflower oil) PUFA for 1 wk. Dietary PUFA and deletion of the LDL‐R had independent effects on HMG‐CoA reductase and serum lipids, and a significant diet‐gene interaction was observed. The effects of PUFA on HMG‐CoA reductase in the mammary gland, but not the liver, were mediated by the LDL‐R. We also observed that differences in HMG‐CoA reductase and serum LDL‐cholesterol, high density lipoprotein cholesterol, and triglycerides between −/− and +/+ mice were dependent on whether the mice were fed n‐3 or n‐6 PUFA. Differences between −/− and +/+ mice were much greater when animals were fed n‐6 PUFA rather than n‐3 PUFA. These results show that the LDL‐R mediates the effects of PUFA on HMG‐CoA reductase in the mammary gland but not the liver. Furthermore, the composition of dietary PUFA profoundly influences the effects of deleting the LDL‐R on HMG‐CoA reductase and serum lipids and suggests that diet may influence the phenotype of other knockout or transgenic animals.
Effects of ψ‐linolenic acid and docosahexaenoic acid in formulae on brain fatty acid composition in artificially reared rats
Authors: Ward G. R. , Huang Y. ‐S. , Xing H. ‐C. , Bobik E. , Wauben I. , Auestad N. , Montalto M. , Wainwright P. E. 
Published: November 2006

AbstractThis study evaluated the effects of dietary supple‐mentation with ψ‐linolenic acid (GLA, 18∶3n−6) and docosahexaenoic acid (DHA, 22∶6n−3) on the fatty acid composition of the neonatal brain in gastrostomized rat pups reared artificially from days 5–18. These pups were fed rat milk substitutes containing fats that provided 10% linoleic acid and 1% α‐linolenic acid (% fatty acids) and, using a 2×3 factorial design, one of two levels of DHA (0.5 and 2.5%), and one of three levels of GLA (0.5, 1.0, and 3.0%). A seventh artificially reared groups served as a reference group and was fed 0.5% DHA and 0.5% arachidonic acid (AA, 20∶4n−6); these levels are within the range of those found in rat milk. The eighth group, the suckled control group, was reared by nursing dams fed a standard American Institute of Nutrition 93M chow. The fatty acid composition of the phosphatidylethanolamine, phosphatidyl‐choline, and phosphatidylserine/phosphatidylinositol membrane fractions of the forebrain on day 18 reflected the dietary composition in that high levels of dietary DHA resulted in increases in DHA but decreases in 22∶4n−6 and 22∶5n−6 in brain. High levels of GLA increased 22∶4n−6 but, in contrast to previous findings with high levels of AA, did not decrease levels of DHA. These results suggest that dietary GLA, during development, differs from high dietary levels of AA in that it does not lead to reductions in brain DHA.
Infant cerebellar gray and white matter fatty acids in relation to age and diet
Authors: Jamieson E. C. , Farquharson J. , Logan R. W. , Howatson A. G. , Patrick W. J. A. , Weaver L. T. , Cockburn F. 
Published: November 2006

AbstractThere is little evidence as to the fatty acid composition of the cerebellum in infancy and it remains uncertain whether milk diet can influence its composition. We therefore examined cerebellar gray and white matter of infants less than 6 mon old who had died unexpectedly. The fatty acid content of 33 gray and 21 white matter specimens from infants born at term and 6 gray and 5 white matter specimens from pretern infants was assessed by gas chromatographic/mass spectrometric analysis. Infants were grouped according to whether they had received human or manufactured formula milk. Whereas cerebellar cortex docosahexaenoic acid (DHA, 22∶6n−3) concentrations were significantly lower (P<0.01) in the formula‐fed than breast‐fed infants, no differences existed between the term (n=10) and preterm (n=5) Scientific Milk Adaptation (SMA) formula‐fed infants. Cerebellar white matter DHA concentrations were similarly lower (P<0.01) in the SMA formula‐fed infants (n=8) than in an age‐matched breast‐fed group. Low concentrations of cerebellar white matter lignoceric (24∶0) and nervonic acid (24∶1n−9) in two 7‐wk‐old preterm infants appeared to correlated with postgestational rather than chronological age. Dietary long‐chain polyunsaturated fatty acids particularly DHA, are probably essential for normal development of the infant cerebellum.
Arachidonic, eicosapentaenoic, and biosynthetically related fatty acids in the seed lipids from a primitive gymnosperm, Agathis robusta
Authors: Wolff Robert L. , Christie William W. , Pédrono Frédérique , Marpeau Anne M. 
Published: November 2006

AbstractThe fatty acid composition of the seeds from Agathis robusta, an Australian gymnosperm (Araucariaceae), was determined by a combination of chromatographic and spectrometric techniques. These enabled the identification of small amounts of arachidonic (5,8,11,14–20∶4) and eicosapentaenoic (5,8,11,14,17–20∶5) acid for the first time in the seed oil of a higher plant. They were apparently derived from γ‐linolenic (6,9,12–18∶3) and stearidonic (6,9,12,15–18∶4) acids, which were also present, via chain elongation and desaturation, together with other expected biosynthetic intermediates [bis‐homo‐γ‐linolenic (8,11,14–20∶3) and bishomo‐stearidonic (8,11,14,17–20∶4) acids]. Also present were a number of C20 fatty acids, known to occur in most gymnosperm families, i.e., 5,11–20∶2, 11,14–20∶2 (bishomo‐linoleic), 5,11,14–20∶3 (sciadonic), 11,14,17–20∶3 (bishomo‐α‐linolenic), and 5,11,14,17–20∶4 (juniperonic) acids. In contrast to most other gymnosperm seed lipids analyzed so far, A. robusta seed lipids did not contain C18 Δ5‐desaturated acids [i.e., 5,9–18∶2 (taxoleic), 5,9,12–18∶3 (pinolenic), or 5,9,12,15–18∶4 (coniferonic)]. These structures support the simultaneous existence of Δ6‐ and Δ5‐desaturase activities in A. robusta seeds. The Δ6‐ethylenic bond is apparently introduced into C18 polyunsaturated acids, whereas the Δ5‐ethylenic bond is introduced into C20 polyunsaturated acids. A general metabolic pathway for the biosynthesis of unsaturated fatty acids in gymnosperm seeds is proposed. When compared to Bryophytes, Pteridophytes (known to contain arachidonic and eicosapentaenoic acids), and species from other gymnosperm families (without such acids), A. robusta appears as an “intermediate,” with the C18 Δ6‐desaturase/C18→C20 elongase/C20 Δ5‐desaturase system in common with the former subphyla, and the unsaturated C18→C20 elongase/C20 Δ5‐desaturase system specific to gymnosperms. The following hypothetical evolutionary sequence for the C18 Δ6/Δ5‐desaturase class in gymnosperm seeds is suggested: Δ6 (initial)→Δ6/Δ5 (intermediate)→Δ5 (final).
Lipids of the pawpaw fruit: Asimina triloba
Authors: Wood Randal , Peterson Scott 
Published: November 2006

AbstractThe fatty acid composition and structure of pawpaw fruit (Asimina triloba) triglycerides were examined and found to contain fatty acids ranging from C6 to C20. Octanoate represented 20% of the fatty acids while other medium‐chain fatty acids were present in low amounts. Analysis of the intact triglycerides by high‐temperature gas‐liquid chromatography gave an unusual three‐cycle carbon number distribution. Analysis of triglyceride fractions separated according to degree of unsaturation suggested that one octanoate was paired with diglyceride species containing long‐chain fatty acids. Determination of the double‐bond positions of monoene fatty acids revealed cis Δ9 and cis Δ11 hexadecenoate and cis Δ9, cis Δ11, and cis Δ13 octadecenoate isomers were present in significant quantities. Octanoate and positional monoene fatty acid isomers were found only in the fruit lipids and not in the seed lipids. Phenacyl esters of fatty acids were found to be useful derivatives for structure determination using multiple types of analyses.
Stability of cyclopropane and conjugated linoleic acids during fatty acid quantification in lactic acid bacteria
Authors: Dionisi Fabiola , Golay Pierre‐Alain , Elli Marina , Fay Lauren B. 
Published: November 2006

AbstractSeven methods commonly used for fatty acid analysis of microgrganisms and foods were compared to establish the best for the analysis of lyophilized lactic acid bacteria. One of these methods involves fat extraction followed by methylation of fatty acids, while the other methods use a direct methylation of the samples, under different operating conditions (e.g., reaction temperature and time, reagents, and pH). Fatty acid methyl esters were identified by gas chromatography‐mass spectrometry and quantified by on‐column capillary gas chromatography. Two reliable methods for the analysis of fatty acids in bacteria were selected and further improved. They guarantee high recovery of classes of fragile fatty acids, such as cyclopropane and conjugated acids, and a high degree of methylation for all types of fatty acid esters. These two direct methylation methods have already been successfully applied to the analysis of fatty acids in foods. They represent a rapid and highly reliable alternative to classical time‐and solvent‐consuming methods and they give the fatty acid profile and the amount of each fatty acid. Using these methods, conjugated linoleic acids were identified and quantified in lactic acid bacteria.
Synthesis of trans‐4,5‐epoxy‐(E)‐2‐decenal and its deuterated analog used for the development of a sensitive and selective quantification method based on isotope dilution assay with negative chemical ionization
Authors: Lin Jianming , Fay Laurent B. , Welti Dieter H. , Blank Imre 
Published: November 2006

AbstractThe volatile compound trans‐4,5‐epoxy‐(E)‐2‐decenal (1) was synthesized in two steps with good overall yields. The newly developed method is based on trans‐epoxidation of (F)‐2‐octenal with alkaline hydrogen peroxide followed by a Wittig‐type chain elongation with the ylide formylmethylene triphenylphosphorane. For the synthesis of [4,5‐2H2]‐trans‐4,5‐epoxy‐(E)‐2‐decenal (d‐1), [2,3‐2H2]‐(E)‐2‐octenal was prepared by reduction of 2‐octyn‐1‐ol with lithium aluminum deuteride and subsequent oxidation of [2,3‐2H2]‐(E)‐2‐octen‐1‐ol with manganese oxide. Compound d‐1 was used as internal standard for the quantification of 1 by isotope dilution assay. Among various mass spectrometry (MS) ionization techniques tested, negative chemical ionization with ammonia as reagent gas gave best results with respect to both sensitivity and selectivity. The detection limit was found to be at about 1 pg of the analyte introduced into the gas chromatography‐MS system.
Acyclic and incompletely cyclized triterpene alcohols in the seed oils of theaceae and Gramineae
Authors: Akihisa Toshihiro , Koike Kazuo , Kimura Yumiko , Sashida Norio , Matsumoto Taiji , Ukiya Motohiko , Nikaido Tamotsu 
Published: November 2006

AbstractThe triterpene alcohol constituents of the non‐saponifiable lipids of two Theaceae seed oils, sasanqua and camellia oils, and two Gramineae seed oils, wheat germ and rice bran oils, were investigated. This led to the isolation and characterization of one acyclic and eight incompletely cyclized triterpene alcohols. They are camelliol A, camelliol B, camelliol C, achilleol A, helianol, isohelianol, sasanquol, graminol A [(13R, 14R)‐3,4‐seco‐25(10→9)abeo‐8α,9β,10α‐podioda‐4,17,21‐trien‐3‐ol], and (2Z,6Z,10Z,14E,18E)‐farnesylfarnesol. Two other compounds isolated were characterized as (2Z,6Z,10E,14E)‐geranylfarnesol, a sesterterpene alcohol, and phytol, a diterpene alcohol. Graminol A and (2Z,6Z,10E,14E)‐geranylfarnesol are considered to be new natural products.
Wax ester‐synthesizing activity of lipases
Authors: Tsujita Takahiro , Sumiyoshi Maho , Okuda Hiromichi 
Published: November 2006

AbstractThe synthesis/hydrolysis of wax esters was studied in an aqueous solution using purified rat pancreatic lipase, porcine pancreatic carboxylester lipase, and Pseudomonas fluorescens lipase. The equilibrium between wax ester synthesis and hydrolysis favored ester formation at neutral pH. The synthesizing activities were measured using free fatty acid or triacylglycerol as the acyl donor and an equimolar amount of long‐chain alcohol as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with these lipases, was ester was synthesized, in a dose‐ and time‐dependent manner, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was about 0.9/0.1. These lipases catalyzed the hydrolysis of palmityl oleate emulsified with gum arabic, and the apparent equilibrium ratio of palmityl oleate/free oleic acid was also about 0.9/0.1. The apparent equilibrium ratio of wax ester/free fatty acid catalyzed by lipase depended on incubation pH and fatty alcohol chain length. When equimolar amounts of trioleoylglycerol and fatty acyl alcohol were incubated with pancreatic lipase, carboxylester lipase, or P. fluorescens lipase, wax esters were synthesized dose‐dependently. These results suggest that lipases can catalyze the synthesis of wax esters from free fatty acids or through degradation of triacylglycerol in an aqueous medium.
Metabolism of n−3 and n−6 fatty acids in Atlantic salmon liver: Stimulation by essential fatty acid deficiency
Authors: Ruyter B. , Thomassen M. S. 
Published: November 2006

AbstractOxidation, esterification, desaturation, and elongation of [1‐14C]18∶2n−6 and [1‐14C]18∶3n−3 were studied using hepatocytes from Atlantic salmon (Salmo salar I.) maintained on diets deficient in n−3 and n−6 polyunsaturated fatty acids (PUFA) or supplemented with n−3 PUFA. For both dietary groups, radioactivity from 18∶3n−3 was incoporated into lipid fractions two to three times faster than from 18∶2n−6, and essential fatty acids (FFA) deficiency doubled the incorporation. Oxidation to CO2 was very low and was independent of substrate or diet, whereas oxidation to acid‐soluble products was stimulated by EFA deficiency. Products from 18∶2n−6 were mainly 18∶3n−6, 20∶3n−6, and 20∶4n−6, with minor amounts of 20∶2n−6 and 22∶5n−6. Products from 18∶3n−3 were mainly 18∶4n−3, 20∶5n−3, and 22∶6n−3, with small amounts of 20∶3n−3. The percentage of 22∶6n−3 in the polar lipid fraction of EFA‐deficient hepatocytes was fourfold higher than in n−3 PUFA‐supplemented cells. This correlated well with our other results obtained after abdominal injection of [1‐14C]18∶3n−3 and [1‐14C]18∶2n−6. In hepatocytes incubated with [4,5‐3H]‐22∶6n−3, 20∶5n−3 was the main product. This retrocon‐version was increased by EFA deficiency, as was peroxisomal β‐oxidation activity. This study shows that 18∶2n−6 and 18∶3n−3 can be elongated and desaturated in Atlantic salmon liver, and that this conversion and the activity of retroconversion of very long chain PUFA is markedly enhanced by FFA deficiency.
Thioglycolate‐elicited rat macrophages exhibit alterations in incroporation and oxidation of fatty acids
Authors: Peres C. M. , Procopio J. , Costa M. , Curi R. 
Published: November 2006

AbstractIncorporation and oxidation of fatty acids (FA) were investigated in resident and thioglycolate‐clicited (TG‐elicited) rat macrophages (Mϕ). Both cell types presented a time‐dependent incorporation of [14C]‐labeled palmitic acid (PA), oleic acid (OA), linoleic acid (LA), and arachidonic acid (AA) up to 6h. The total amount of [14C]‐FA incorporated by resident Mϕ after 6 h was: AA>PA=LA>OA. TG‐elicited cells presented a 50% reduction in the incorporation of LA, PA, and AA, whereas that of OA remained unchanged as compared to resident Mϕ. The FA were oxidized by resident Mϕ as follows: LA>OA>PA>AA. TG elicitation promoted a reduction of 42% in LA oxidation and a marked increase in AA oxidation (280%). The increased oxidation of AA in TG‐elicited cells may account for the lower production of prostaglandins in Mϕ under these conditions. The full significance of these findings for Mϕ function, however, remains to be examined.
Fatty acid Δ9‐Desaturation in the Triatoma infestans fat body: Response to food and trehalose administrationsin the Triatoma infestans fat body: Response to food and trehalose administrations
Authors: González María S. , Brenner Rodolfo R. 
Published: November 2006

AbstractThe effects of food intake and carbohydrate administration on fatty acid Δ9‐desaturation were investigated in isolated microsomes from Triatoma infestans fat body. Fifth instar nymphs, which were solely blood‐fed just after the molt and then fasted, were used as controls and for determination of optimal assay conditions. Both [1‐14C]palmitic and [1‐14C]stearic acids in a medium containing ATP, CoA, MgCl2, NADH, NaF, and O2 were tested. For the control group, optimal conditions were a pH of 6.8–7.2, an incubation temperature of 29°C, and an incubation time of 10 min. Δ9‐desaturation depended on the presence of reduced pyridine dinucleotides; NADH and NADPH were equally efficient. Stearic acid showed a higher apparent Vmax than palmitic acid, but the apparent Km were very similar. When fifth instar nymphs were blood‐fed weekly, a marked increase of Δ9‐desaturation was observed for both acids. Higher desaturation activity was also induced by injection of the carbohydrate trehalose into the hemolymph of fasted nymphs. These results indicate that insect Δ9‐desaturation, like the mammalian counterpart, is sensitive to dietary changes and carbohydrate administration. *** DIRECT SUPPORT *** A01K6035 00008
Lipid composition of eggs of an oviparous lizard (Bassiana duperreyi)
Authors: Speake Brian K. , Thompson Michael B. , McCartney Ruth J. 
Published: November 2006

AbstractLipid analysis was performed on freshly ovulated eggs (n=5) of the oviparous lizard Bassiana duperreyi. The fresh weight of the whole egg contents was 132.0±4.3 mg (mean+SF) of which lipid constituted 21.9+1.1% (w/w). Iriacylglycerol formed an exceptionally high proportion (85.4+ 0.5%, w/w) of the total lipid, whereas phospholipid, free cholesterol, cholesteryl ester, and free fatty acid, respectively, contributed 11.2±0.3, 1.4±0.1,1.3±0.1, and 0.6±0.1% of the total lipid mass. Linoleic and α‐linolenic acids were the major polyunsaturates of the triacylglycerol fraction, respectively, forming 16.3±0.1 and 8.3±0.1% (w/w) of the fatty acids. Linoleic acid was the major fatty acid (29.0±0.1%) of the total phospholipid, which also contained substantial amounts of arachidonic (6.4±0.1%) and eicosapentaenoc (3.0±0.1%) acids, but a relatively low proportion (1.6±0.1%) of docosahexaenoic acid. Phosphatidylcholine formed the major phospholipid class (73.8±2.3% w/w of total phospholipid) and was enriched in linodeic acid, whereas phosphatidylethanolamine, which formed 20.4±1.9% (w/w) of total phospholipid, contained higher proportions of arachidonic and docosahexaenoic acids.
Competition between Li+ and Mg2+ for red blood cell membrane phospholipids: A 31P, 7Li, and 6Li nuclear magnetic resonance study
Authors: Srinivasan Chandra , Minadeo Nicole , Geraldes Carlos F. G. C. , de Freitas Duarte Mota 
Published: November 2006

AbstractThe mode of action of the lithium ion (Li+) in the treatment of manic depression or bipolar illness is still under investigation, although this inorganic drug has been in clinical use for 50 yr. Several research reports have provided evidence for Li+/Mg2+ competition in biomolecules. We carried out this study to characterize the interactions of Li+ and Mg2+ with red blood cell (RBC) membrane components to see whether Li+/Mg2+ competition occurs. 31P nuclear magnetic resonance chemical shift measurements of the phospholipids extracted from the RBC membranes indicated that the anionic phospholipids, phosphatidylserine and phosphatidylinositol, bind Li+ and Mg2+ most strongly. From 6Li relaxation measurements, the Li+ binding constant to the phospholipid extract was found to be 45±5M−1. Thus, these studies showed that the phospholipids play a major role in metal ion binding. 7Li spin‐lattice relaxation measurements conducted on unsealed and cytoskeleton‐depleted RBC membrane in the presence of magnesium indicated that the removal of the cytoskeleton increases lithium binding to the more exposed anionic phospholipids (357±24 M−1) when compared to lithium binding in the unsealed RBC membrane (221±21 M−1). Therefore, it can be seen that the cytoskeleton does not play a major role in Li+ binding or in Li+/Mg2+ competition.