bluuebunny/crossref_metadata_2025_split huggingface dataset:
The absorption of fatty acids by functional bovine mammary cells
Authors: Kinsella John E. 
Published: November 2006

AbstractFreshly dispersed bovine mammary cells rapidly absorbed long chain fatty acids from the culture medium. Differences in the rates of absorption were observed, i.e., palmitic > stearic > oleic > myristic > linoleic acid. The preponderance of the fatty acids absorbed were esterified into triglycerides (>75%) and the remainder were mostly incorporated into phospholipids. The cells secreted triglycerides into the culture medium. Of the phospholipid classes, phosphatidylcholine always contained most of the radioactivity in all experiments with labeled fatty acids. These observations are related to the metabolism of mammary cells in vivo.
The fatty acids ofEntomophthora coronata
Authors: Mumma R. O. , Bruszewski T. E. 
Published: November 2006

AbstractThe total lipids and fatty acid composition ofEntomophthora coronata were determined. The fungus was grown on a chemically defined medium and a chemically nondefined medium (Sabouraud dextrose yeast extract) for a period of 26 days. The organism contained from 16.2% to 44.6% total lipids depending upon the days of growth. The major fatty acids were 12∶0 (5.5–9.0%), 13∶0 (1.2–8.2%), 14∶0 (33.5–43.5%), 16∶0 (9.7–13.9%), 18∶19 (20.4–22.4%), and 18∶29,12 (3.5–10.5%). Lesser amounts of 15∶0, 16∶1, 16∶2, 17∶0, 18∶0, two other 18∶2 (both having conjugated double bonds), 18∶36,9,12, another 18∶3 (conjugated double bonds), 20∶38,11,14, 20∶45,8,11,14, another 20∶4 (conjugated double bonds), and 24∶1 acids were found. Trace amounts of 20∶0, 20∶1, 20∶2, 22∶0 and 24∶0 were also present. The relative percentage of most of the fatty acids did not vary appreciably with growth. However, 18∶29,12 and 20∶45,8,11,14 increased with age of the chemically defined culture. Peak E (18∶2, conjugated double bonds) increased and 13∶0 and 18∶36,9,12 decreased with age of the chemically nondefined culture. The fatty acids were predominately saturated (56.9–69.1%) and contained a high percentage of shorter chain fatty acids (C 12 to C 15). The fatty acids of the chemically defined culture were more unsaturated than the Sabouraud culture and the unsaturation increased with age of the culture.
Aliphatic hydrocarbon contents of various members of the family micrococcaceae
Authors: Tornabene T. G. , Morrison Susan J. , Kloos W. E. 
Published: November 2006

AbstractThe composition and nature of the hydrocarbons of various members of the family Micrococcaceae were studied by gas chromatography. The hydrocarbons found inSarcina lutea strains,Sarcina flava, Sarcina subflava, Micrococcus lysodeikticus strains and their transformed hybrids consisted of monounsaturated hydrocarbons showing either iso or anteiso methyl branching. The hydrocarbons of the various organisms differed in the range of hydrocarbon distribution, the relative proportions of the major hydrocarbon fractions and the individual components within each fraction.Staphylococcus aureus strains andGaffkya tetragena contained no appreciable quantities of hydrocarbons. The fatty acid compositions of theSarcina species, Micrococcus lysodeikticus strains and the strains derived by transformation were qualitatively identical.Staphylococcus aureus andGaffkya tetragena showed similar fatty acid patterns that were different from those ofSarcina andMicrococcus. A taxonomic relationship between these organisms was established on the basis of the hydrocarbon compositions.
Effects of fatty acid concentration and positional specificity on maize triglyceride structure
Authors: De La Roche I. A. , Weber Evelyn J. , Alexander D. E. 
Published: November 2006

AbstractThe effects of fatty acid concentration and positional specificity on maize triglyceride structure were evaluated from the stereospecific analyses of triglycerides from 12 genotypes. The fatty acids at each position were influenced by the fatty acid concentration in the total triglyceride except for the saturates in the 2 position. The fatty acid concentration had the greatest effect on the fatty acid composition of position 3. The existence of positional specificity was evident from the nonrandom distribution of the fatty acids among the three positions of the triglycerides. The concentration and positional specificity effects could be separated in selected genotypes and their crosses. This indicated different genetic controls for each effect.
The selective utilization of diglyceride species into maize triglycerides
Authors: De La Roche I. A. , Weber Evelyn J. , Alexander D. E. 
Published: November 2006

AbstractThe maize triglycerides were resolved into species by silver nitrate thin layer chromatography. The distribution of the fatty acids among the 1, 2 and 3 positions of each triglyceride species was determined by stereospecific analysis. From these data the relative amounts of each positional isomer were calculated. The results indicate that esterification of the fatty acids at each position proceeds with a specificity that is correlated with the composition of the other positions of the triglyceride.
Lipid monolayers: Influence of lipid film and urea on the surface activity of staphylococcal α‐toxin
Authors: Colacicco Giuseppe , Buckelew Albert R. 
Published: November 2006

AbstractUnder conditions in which neither ribonuclease nor lysozyme formed a film by either spreading or adsorption at the air‐water interface, the surface activity of staphylococcala‐toxin and streptolysin S in the absence of lipid was greatly enhanced by the presence of 6 M urea in the hypophase. The influence of urea on the anchoring of the protein was quantitatively similar to that of a lecithin film. Admixture of up to 50 mole % cholesterol to egg lecithin preserved the lecithin character of the lipid monolayer in the penetration ofa‐toxin, suggesting probably binding of cholesterol to phosphatidyl choline in the presence of excess lecithin. Penetration ofa‐toxin and streptolysin S into the air‐water interface was inhibited by lipid monolayers containing gangliosides. The inhibition, however, was removed when the subphase contained 6 M urea. The resulting penetration curve ofa‐toxin was identical with the penetration curve of the protein into the lecithin film in the absence or in the presence of urea. In general, the denaturing agent causes the protein to acquire a hydrated conformation, from which restructuring in the low dielectric constant of air or lipid is favored and brings about results comparable with those effected by the lipid. Pre‐incubation ofa‐toxin with gangliosides or sulfatides caused a marked decrease in film penetration of the toxin into lecithin monolayers. Unlikea‐toxin, streptolysin S was extremely sluggish in penetration of the air‐water interface and of several lipid monolayers. Protein concentration, a complement of either lipid or membrane protein, and specific molecular organizations of membranes must be taken into account in all cases; they, in particular, may be the basis for the enhanced cytolytic activity of streptolysin S in vivo.
Comparative citrus fatty acid profiles of triglycerides, monogalactosyl diglycerides, steryl esters and esterified steryl glucosides
Authors: Nordby Harold E. , Nagy Steven 
Published: November 2006

AbstractVesicular lipids from six orange and two tangor varieties were extracted, purified and separated by chromatography into triglycerides, monogalactosyl diglycerides, steryl esters and esterified steryl glucosides. Methyl esters of the fatty acids found in these four lipids were prepared and analyzed by gas liquid chromatography. Each of the eight citrus varieties gave a series of four profiles which could be distinguished from the others. The Temple tangor has four profiles all showing a large percentage of linolenic acid. In all varieties steryl esters and to a lesser extent esterified steryl glucosides contain relatively large concentrations of 22∶0 to 26∶0 saturated acids. The profiles differ markedly from the patterns found for these four lipids in other higher plants studied.
Wax esters in fish: Turnover of oleic acid in wax esters and triglycerides of gouramis
Authors: Sand D. M. , Hehl Jean L. , Schlenk H. 
Published: November 2006

AbstractMethyl U‐14C oleate was fed to mature male and female gouramis (Trichogaster cosby) and the radioactivity in lipids measured over a period of four months. Initial incorporations were 70–80% and more than half of that was still in the lipids at the end of the experiment. Very little conversion of the 18∶1 chain had occurred. Main storage of the labeled 18∶1 chain was in the wax esters of the roe and in the triglycerides of the body. In the wax esters, 18∶1 occurred in both the alcohol and acid moieties. Initially the females had less radioactivity in the triglycerides than in the wax esters but at the end of the experiment this was reversed. An appreciable amount of 18∶1 had been transferred from roe to body lipids. The biological half life of 18∶1 in gouramis is estimated to be about four months. This time is equal for males and females although translocation from roe to body and transformation of wax ester to triglyceride take place in the female, whereas wax esters do not play any role in the lipid metabolism of the male.
The desaturation step in the animal biosynthesis of polyunsaturated fatty acids
Authors: Brenner Rodolfo R. 
Published: November 2006

AbstractThe aerobic desaturation of unsaturated fatty acids in the microsomes has been systematically explored and some of the relevant experimental works have been assembled. The contribution of the microsomal electron transport chain and lipoproteic structure of the microsomes is analyzed. Evidences of linoleyl‐CoA and α‐linolenyl‐CoA being desaturated by the same enzyme are presented. The linoleic acid desaturation is shown to be different in different tissues and to decrease with aging. The effect of competitive reactions with acids of the same or different series, the competition of desaturation and transesterification, and dietary and hormonal contributions to unsaturated fatty acids desaturation are summarized. Alltrans linoleic acid and elaidic acid were not desaturated in our experimental conditions by rat liver microsomes. From the bulk of data collected, a hypothetical model of 6‐olefinase is drawn. The main features of the model are: The existence of both binding and desaturating sites; the binding of acyl‐CoA and enzyme through hydrophobic forces of the Van der Waals type and weak polar attractions due to double bonds; the orienting binding characteristics of double bond proximate to the place where olefination will take place; and the importance of enzyme conformation that requires that the orienting double bond must have acis structure.
Thermophilic fungi: III. The lipids ofHumicola grisea var.thermoidea
Authors: Mumma R. O. , Sekura R. D. , Fergus C. L. 
Published: November 2006

AbstractThe lipids of the thermophilic fungusHumicola grisea var.thermoidea were qualitatively and quantitatively determined. The polar lipids consisted of 38.4–42.3% of the total lipids. The relative per cent phospholipids based upon the total phospholipids were as follows: phosphatidyl choline, 32.3–33.7%; phosphatidic acid, 24.5–31.7%; phosphatidyl ethanolamine, 15.8–20.9%; phosphatidyl inositol, 12.5–13.0%; phosphatidyl serine, 2.3–5.4%; and diphosphatidyl glycerol, 3.9–4.0%. The relatively high concentration of phosphatidic acid may be characteristic of fungi grown at elevated temperatures. Several sterol glycosides (3.1–6.0%) were present in the polar lipids. The neutral lipids consist of triglycerides, 28.6–36.0%; free fatty acids, 5.3–13.5%; sterols, 11.4–13.9%; sterol esters, 1.8–3.0%; and diglycerides, 2.2–3.4%. The sterols and derivatives comprise an unusually large fraction of the total lipids (16.3–22.9%) suggesting a role in thermostability.
Metabolic studies in isolated rat liver cells: I. Lipid synthesis
Authors: Capuzzi David M. , Margolis Simeon 
Published: November 2006

AbstractRat liver cells, isolated by chelate perfusion and extrusion through a tissue press, incorporated labeled acetate into cellular lipids and into lipids released into the suspending medium. Optimal rates of incorporation required supplementation of tris‐KCl medium with Mg++, Mn++, succinate, citrate, nicotinamide, Coenzyme A, NADP and glucose‐6‐phosphate. The rate of acetate incorporation was markedly altered by changes in incubation media; tris‐KCl was the most effective buffer. All the major classes of cellular lipids were labeled. ATP, BSA, inorganic phosphate, Ca++, 2,4‐dinitrophenol and sodium clofibrate were potent inhibitors of acetate incorporation. When added to the incubation mixture, several hormones altered the rate of acetate incorporation into lipids.
The iodination of methyl sterculate and deiodination of the product to reform the cyclopropenoid ring
Authors: Rosie D. A. , Shone G. G. 
Published: November 2006

AbstractUnlike the addition of iodine to alkenes, the radical addition of iodine to methyl sterculate has been shown to be facile at room temperature. The 1,2‐diodocyclopropanoid material produced has been deiodinated to regenerate the cyclopropenoid ring.
On the phospholipids ofCulex pipiens fatigans
Authors: Subrahmanyam D. , Moturu L. B. , Hanumantha Rao R. 
Published: November 2006

AbstractThe lipids of different developmental stages ofCulex pipiens fatigans, vector of bancroftian filariasis, have been investigated. The phospholipid composition of the developmental stages and of the subcellular fractions of fourth instar larvae of the insects were analyzed. The composition of fatty acids and their positional distribution have also been examined in the major phospholipids of the larvae. The insect eggs contained higher amounts of lipids than larvae suggesting that they were utilized during embryogenesis. Phosphatidyl ethanolamine (PE) and phosphatidyl choline (PC) comprised over 75% of the insect phospholipids. Of these, PE was present in the greatest amounts during all stages of growth and in the subcellular fractions of larvae. An ethanolamine containing sphingolipid was found as a component of the phospholipids of the insects. About 50% of the lipids of the larvae were localized in the cell debris and nuclei fraction which also contained most of the lysolipids of the insects. As in other Diptera 16∶0, 16∶1 and 18∶1 were the major fatty acids present in the insect lipids of which the fatty acid found in greatest amounts was 16∶1. Similar to the phospholipids of animal species, saturated fatty acids were predominantly linked to the 1 position of the major phospholipids of the insects while the unsaturated fatty acids were in higher amounts at the 2 position.
Metabolism of labeled isomeric octadecenoates by the laying hen
Authors: Mounts T. L. , Emken E. A. , Rohwedder W. K. , Dutton H. J. 
Published: November 2006

AbstractDiscrimination between octadecenoic acid isomers by the laying hen has been studied using tritium (3H), carbon‐14 (14C) and deuterium (d) labeled oleate and elaidate esters. Hydrogen isotopes were positioned at the double bond, whereas14C was located in the 1‐, carboxyl carbon. The egg acted as a biological trap, providing an automatic daily biopsy with which to study the metabolism of the fed isomers. Monitoring the incorporation of isomers was facilitated by dual label feeding experiments, and3H/14C, d2/do and d2/d1 ratios were determined on the isomeric mixtures fed, on the total egg lipids extracted and on the isolated neutral lipid and phospholipid fractions. Comparison of isotopic ratios of the fed mixture and of the lipid fractions provided an evaluation of discrimination by the hen during the transport of isomeric octadecenoates into the egg lipids. Radioactive and stabl isotope ratios determined for the neutral lipid indicated a preferential incorporation of thecis isomer. Stable isotope ratios determined for the phospholipid showed that thetrans isomer is preferentially incorporated. The3H/14C ratios for the phospholipid recovered in each experiment increased greatly whichever isomer was labeled with3H, indicating an elimination of the 1‐14C‐label. Gas liquid radiochromatographic separation of the methyl esters from the neutral lipids and phospholipids showed that the isotopic labels were present almost exclusively in the octadecenoic acid constituent.
Alcoholysis, saponification and the preparation of fatty acid methyl esters
Authors: Glass R. L. 
Published: November 2006

AbstractEvidence is offered to support the contention that methanolysis precedes the saponification of esters in methanolic solutions of sodium hydroxide. This results from the hydroxide‐alkoxide equilibrium which greatly favors methoxide formation even in the presence of rather considerable amounts of water. Saponification‐reesterification methods of methyl ester formation are shown to be actually extensions of methanolysis procedures. A simplified method is proposed for the preparation of fatty acid methyl esters.
Stereospecific analysis of triglycerides
Authors: Brockerhoff H. 
Published: November 2006

AbstractStereospecific analysis determines how the fatty acids of triglycerides are distributed over the three different positions of the glycerol. The special problem is the differentiation of position I‐1 and L‐3 of glycerol. In the presently known methods, triglycerides are first degraded to mixtures of diglycerides, either by the action of a lipase or by degradation with a Grignard reagent. The isomeric diglycerides are then resolved with the help of a stereospecific enzyme, either a diglyceride kinase or (after conversion of the diglycerides to phospholipids) a phospholipase. It is then possible to analyze or calculate the fatty acid composition for each position on the glycerol. The key to a successful stereospecific analysis is the preparation of a representative diglyceride mixture by a truly random degradation of the triglyceride. The Grignard degradation is the most reliable method, but it is not always applicable, and it is accompanied by some isomerization of glycerides. There is room for improvement in the method. Analyse of natural fats have shown most of them to be asymmetric, i.e., the composition of fatty acids in position 1 differs markedly from that of position 3. Several rules of fatty acid distribution have become apparent.
Ricinoleic acid inLinum mucronatum seed oil
Authors: Kleiman R. , Spencer G. F. 
Published: November 2006

AbstractLinum mucronatum seed oil contains 15% ricinoleic [(+)‐12‐D‐hydroxy‐cis‐9‐octadecenoic] acid, previously unknown in the Linaceae. Identification was made by IR, gas liquid chromatography, nuclear magnetic resonance, ozonolysis and mass spectrometry. Other major components of the oil are oleic acid (24%) and linoleic acid (48%).
Structural relationships between glycerides of pig serum and adipose tissue
Authors: Grigor M. R. , Blank M. L. , Snyder Fred 
Published: November 2006

AbstractStructural analyses have been performed on the triacylglycerols and phosphoglycerides isolated from adipose tissue, serum chylomicrons, and serum lipoproteins from pigs. The triacylglycerols from adipose tissue contained mainly palmitate esterified at the 2 position of the glycerol moiety, whereas those from the serum had predominately
Calculation of the NMR spectrum of double‐bond protons in aliphatic systems
Authors: Schaumburg K. , Bernstein H. J. 
Published: November 2006

AbstractA simplified subspectral method is presented to determine coupling constants and chemical shifts for the group −CH2 −CH=CH−CH2− in aliphatic compounds. Results are given for methyl esters of oleic, elaidic, erucic, and linoleic acid. These results are in agreement with more elaborate calculations.
Influence of sex and gonadal hormones on lipid metabolism in essential fatty acid‐deficient rats
Authors: Ostwald Rosemarie , Lyman Richard L. 
Published: November 2006

AbstractPrevious work has shown differences between male and female rats in their ability a) to mobilize linoleic acid from adipose tissue when the supply is limited; b) to maintain higher levels of circulating and liver arachidonic acid when dietary linoleic acid is limited; c) to prevent accumulation of cholesteryl ester (CE) in the liver; and d) to increase the proportions of polyunsaturated fatty acids (PUFA) in their plasma lecithins.Recent studies are reviewed which show that a) essential fatty acid (EFA)‐deficient rats exhibit the same kinds of sex differences as do rats on complete diets; b) these differences are mediated or at least influenced by estrogen; c) some of the differences may be attributed to differences in body size which result in less need for PUFA in structural phospholipid (PL); d) the rate of conversion of linoleic to arachidonic acid may differ under certain experimental conditions; and e) female rats have higher proportions of stearic and arachidonic acids in their liver lecithins than do males, which may relate to their higher rate of lecithin synthesis via methylation of phosphatidyl‐ethanolamine.
Retinol inhibition of some proteolytic enzymes
Authors: Tappel A. L. , Dillard C. J. 
Published: November 2006

AbstractAutomated analyses were used to determine the effect of retinol on the activity of the following proteolytic enzymes: ficin (EC 3.4.4.12), bromelain (EC 3.4.4. 24), trypsin (EC 3.4.4.4.), chymotrypsin A (EC 3.4.4.5), papain (EC 3.4.4.10), clostridiopeptidase A (EC 3.4.4.19), pepsin (EC 3.4.4.1), cathepsin D (EC 3.4.4. 23) from rat‐liver and rat‐kidney lysosomes and the nonspecific proteolytic enzyme, pronase. Of these proteolytic enzymes only ficin, bromelain, and rat‐kidney lysosomal cathepsin D were inhibited significantly by 1×10−4 M retinol.Some nonproteolytic enzymes not inhibited by retinol were acid phosphatase (EC 3.1.3.2), β‐acetylglucosaminidase (EC 3.2.1.30), arylsulfatase (EC 3.1.6.1), and pyruvate kinase (EC 2.7.1.40). The inhibition of cathepsin D varied with the substrate used, being greater with hemoglobin than with ovalbumin or bovine serum albumin. Carotene and retinol inhibited ficin and cathepsin D to similar extents. Retinol inhibition of ficin was partially reversible. These studies of proteolytic enzyme inhibition by retinol serve as a simple model for studying retinol‐protein interactions in vitro.
The total synthesis of phosphatidyl(Dioleoyl)hydroxy‐l‐proline and its activity in blood‐clotting systems
Authors: Turner D. L. , Silver M. J. , Holburn R. R. , Baczynski E. 
Published: November 2006

AbstractThe phthalimidomethyl ester ofN‐anisyloxycarbonyl‐hydroxy‐l‐proline was combined with phosphorus oxychloride andrac‐1,2‐diolein. The diolein was made by large‐scale preparative application of the method of Krabisch and Borgström (1). The protected phosphatide, obtained by the phosphorylation reaction, was stripped of its protective groups under mild conditions. The phosphatidyl(dioleoyl)‐hydroxy‐l‐proline was purified by TEAE cellulose (acetate) chromatography, as developed by Rouser (6), also by silicic acid chromatography. Aqueous dispersions of the material were tested for anticoagulant activity in the antithrom‐boplastin test and the Hicks‐Pitney test. The new phosphatide had about one‐tenth of the activity of beef brain phosphatidylserine.
An unsaturated phosphonic acid analogue of phosphatidylethanolamine and its activity in blood‐clotting systems
Authors: Turner D. L. , Silver M. J. , Holburn R. R. , Baczynski E. , Brown Ann Brooker 
Published: November 2006

AbstractAn unsaturated phosphonolipid analogous to phosphatidylethanolamine,rac‐dioleoylglyceryl(2‐aminoethyl)phosphonate, was synthesized by a general method introduced by Baer for similar saturated substances. An improvement was made in the preparation of the phthalimidoethyl‐phosphonic acid precursor.The phosphonolipid was purified by DEAE cellulose and silicic acid chromatography. It was tested by comparison with synthetic phosphatidyl (dioleoyl) ethanolamine and phosphatidyl(dilinoleoyl) ethanolamine in the Hicks‐Pitney test and in a test for prothrombin conversion by using purified blood coagulation factors. In both tests it had more acceleratory activity than the synthetic phosphatidylethanolamines.