bluuebunny/crossref_metadata_2025 huggingface dataset:
The absorption of fatty acids by functional bovine mammary cells
Authors: Kinsella John E.
Published: November 2006

Freshly 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

The 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

The 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

The 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

The 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

Under 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

Vesicular 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

Methyl 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

The 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

The 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

Rat 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

Unlike 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

The 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

Discrimination 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

Evidence 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

Stereospecific 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.
Determination of the position of ethylenic linkages in lipids
Authors: Kusamran K. , Polgar N.
Published: November 2006

A new procedure for determining the position of ethylenic linkages in lipids involves oxidation of the corresponding epoxides with ethereal periodic acid. The oxidation products are identified by standard techniques such as nuclear magnetic resonance spectroscopy, mass spectrometry and gas liquid chromatography.
Ricinoleic acid inLinum mucronatum seed oil
Authors: Kleiman R. , Spencer G. F.
Published: November 2006

Linum 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

Structural 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

A 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

Previous 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

Automated 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

The 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

An 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.
The lipids of the common house cricket,Acheta domesticus L. II. Hydrocarbons
Authors: Hutchins Roderick F. N. , Martin Michael M.
Published: November 2006

The hydrocarbons of the common house cricketAcheta domesticus L. consist ofn‐alkanes (4%), 2‐methylalkanes (20%), x‐methylalkanes (59%), an unidentified series of alkanes (trace), and olefins (16–185). The major n‐alkane isn‐nonacosane (3.5%). The major 2‐methylalkanes are 2‐methyloctacosane (8%) and 2‐methyltriacontane (11%). The members of the homologous x‐methylalkane series consist of mixtures of methylalkanes in which the methyl side‐chain is located on the 13th, 15th, and 17th carbon atom in the chain. The major x‐methylalkanes are the homologues containing 31 (3%), 33 (6.5%), 35 (12.5%), 37 (27%), and 39 (2.5%) carbon atoms. The olefins are a mixture of straight‐chain and 2‐methyl‐alkenes and alkadienes. The major olefins contain 31 (3%) and 37 (7.5%) carbon atoms.
The lipids of the common house cricket,Acheta domesticus L. III. Sterols
Authors: Martin Michael M. , Carls Glen A.
Published: November 2006

Sterols constitute 1.95% of the total extractable lipids ofAcheta domesticus L., of which 18% are esterified. The free sterols consist of cholestane‐3β‐ol (0.5%), Δ5‐cholestene‐3β‐ol (83.5%), Δ7‐cholestene‐3β‐ol (2.3%) Δ5,7‐cholestadiene‐3β‐ol (3%), Δ5,22‐cholestadiene‐3β‐ol (4%), Δ5,7,22‐cholestatriene‐3β‐ol (0.2%), campestane‐3β‐ol (0.03%), Δ5‐campestene‐3β‐ol (1.0%), Δ7‐campestene‐3β‐ol (trace), Δ5,7‐campestadiene‐3β‐ol (0.2%), stigmastane‐3β‐ol (0.09%), Δ5‐stigmastene‐3β‐ol (2.1%), Δ7‐stigmastene‐3β‐ol (0.04%), Δ5,7‐stigmastadiene‐3β‐ol (0.4%), Δ5,22‐stigmastadiene‐3βol (0.1%). The same sterols are present in the esterified sterol fraction. Δ7‐Sterols and Δ5,7‐sterols are present in significantly larger amounts in the esterified fraction than in the free sterol fraction. By a comparison with the sterols of the cricket food, it is clear thatA. domesticus is capable of removing methyl and ethyl groups from C‐24 of sterols of the campestane and stigmastane type. The ability to introduce a Δ7 double bond into saturated and Δ5‐sterols is indicated, and it is suggested that Δ7‐sterols of the C27, C28, and C29 sterol series may be intermediates in the conversion of Δ5‐sterols to Δ5,7‐sterols.
Isolation of cerebroside containing glucose (Glucosyl ceramide) and its possible significance in ganglioside synthesis
Authors: Nishimura Kenji , Yamakawa Tamio
Published: November 2006

A small amount of cerebroside containing glucose (glucosyl ceramide) was isolated from bovine brain by Florisil column chromatography and thin‐layer chromatography. The fatty acids of the glucosyl ceramide were palmitic and stearic acids; small amounts of oleic and linoleic acids were present.

Rat brain tissue slices, incubated with U‐14C‐glucose, incorporated more radioacivity into glucosyl ceramide than into galactosyl ceramide. From these results the possible metabolic significance of the brain glucosyl ceramide in ganglioside metabolism is discussed.
Studies on the lipids of sheep red blood cells. II. The incorporation of phosphorus into phospholipids of HK and LK cells
Authors: Nelson Gary J.
Published: November 2006

The incorporation of inorganic phosphate (as NaH2PO4) into the phospholipids of sheep red blood cells was studied in vitro in blood samples from five highpotassium (HK) and five low‐potassium (LK) sheep. The erythrocytes from HK sheep incorporated more activity in 4 hr than those from the LK sheep. However no activity was incorporated into the major phospholipids of the cells (phosphatidyl ethanolamine, phosphatidyl serine, and sphingomyelin) of either group. The phosphatidic acid fraction was labeled in both groups and to a significantly greater extent in the HK samples. However the highest activity in the phospholipid of sheep red‐cells was located in three unknown compounds not previously detected. Their specific activities were the same in the HK and the LK samples although they were present in slightly larger amounts in the HK samples. In general, incorporation was at a rather low level, and from stoichiometric considerations it was concluded that the metabolism in the red‐cell phospholipids could not be directly involved in the active transport of ions across the cell membrane. This work also confirmed a previous report that no quantitative differences exist among the major phospholipid classes in the two types of cells.
Thealpha‐oxidation system of brain microsomes. Cofactors foralpha‐hydroxy acid decarboxylation
Authors: MacDonald Robert C. , Mead James F.
Published: November 2006

A one‐carbon degradation of long‐chain fatty acids, which was found to occur in the brains of rats in vivo, has been investigated in a brain microsomal fraction in vitro. Decarboxylation of the α‐hydroxy acid, a possible intermediate product between the substrate and the next shorter acid, in the presence of brain microsomal fraction was enhanced by ATP, NAD, and a dialyzable fraction from the supernatant fraction. The cofactor requirement for the decarboxylation of the α‐hydroxy acids provided by the dialyzable fraction can be met by several reducing agents or ferrous ion. The effectiveness of several possible cofactors for the decarboxylation of α‐hydroxy acids has been evaluated.

It is concluded that the decarboxylation of the α‐hydroxystearic acid may be a reaction with molecular oxygen catalyzed by an oxidase or oxygenase that requires iron in the reduced state for activity. The possibility that the reaction proceeds through an α‐keto acid intermediate has been examined in the light of new knowledge of the conditions for decarboxylation. It is concluded that a short‐lived keto acid is a possible intermediate. Definitive proof however is lacking because the characteristics of the reaction require that such an intermediate decarboxylate without dissociating from the enzyme.
Hydrocarbon cooxidation in microbial systems
Authors: Raymond R. L. , Jamison V. M. , Hudson J. O.
Published: November 2006

This review summarizes the present status of hydrocarbon cooxidation in microorganisms. Hydrocarbons, which cannot be used for growth by many soil microorganisms, can be oxidized if present as co‐substrates in systems in which another substrate is furnished for growth. Paraffinic, cycloparaffinic and aromatic hydrocarbon cooxidations have been demonstrated. Most hydrocarbon cooxidation reactions seem to involve the incorporation of molecular oxygen by mono‐ and dioxygenases. From paraffinic hydrocarbons, products accumulating in fermentation systems include acids, alcohols, aldehydes and ketones. Usually, the initial attack is at the terminal methyl group in paraffin oxidations. The only products isolated in the cycloparaffins have been ketones. Extensive studies have been carried out on cooxidation of mono‐ and dicyclic aromatic hydrocarbons. Oxidation of methyl substituents on aromatic rings usually results in the accumulation of the aromatic mono acid or alcohol. Dihydroxylation of the aromatic ring has been observed. Products of aromatic ring rupture arise via both ortho and meta cleavage pathways.
Ether‐containing lipids of the slime mold,Physarum polycephalum: II. Rates of biosynthesis
Authors: Poulos Alfred , Thompson Guy A.
Published: November 2006

The in vivo incorporation of 1‐14C‐palmitic acid and 1‐0‐[8,9‐3H] hexadecyl glycerol (chimyl alcohol) by plasmodia of the slime mold,Physarum polycephalum has been studied.14C‐palmitate rapidly enters ester and alkyl ether side chains of phospholipids, but alk‐1‐enyl side chains are labeled more slowly.3H‐chimyl alcohol is incorporated into the alkyl ether phospholipids, which appear to undergo enzymatic desaturation, producing plasmalogens. The feasibility ofPhysarum as the source of a cell‐free enzyme system for plasmalogen synthesis is discussed.
The lipids of krill (Euphausia species) and red crab (Pleuroncodes planipes)
Authors: Van der Veen J. , Medwadowski B. , Olcott H. S.
Published: November 2006

The composition of the lipids of two samples of krill and one of “red crab” was determined by thin layer, column and gas chromatographic procedures. A large number of unusual fatty acids were present.
Cellularity of adipose tissue in cold‐exposed rats and the calorigenic effect of norepinephrine
Authors: Therriault Donald G. , Mellin Donald B.
Published: November 2006

Adipose tissue in rats maintained at normal ambient temperature grows by a mixture of hyperplasia and hypertrophy in the early growth stage of the rat. In the mature rat, the tissue grows primarily by hypertrophy. When the rat is acclimated to 5 C, growth of adipose tissue occurs primarily by hyperplasia throughout the body weight ranged studied. As a consequence adipose tissue from rats maintained in the cold has a much larger number of fat cells which are much smaller in size. In order to achieve the adaptation which permits hyperplasia to continue throughout the adult stage the animal must be exposed to cold at an early age, and it requires that the animal remain in the cold to continue. These changes in adipose tissue fat cell size and number are discussed in relation to the increased calorigenic and lipolytic effect of norepinephrine in cold‐acclimated rats.
Identification and analysis of wax esters by mass spectrometry
Authors: Aasen A. J. , Hofstetter H. H. , Iyengar B. T. R. , Holman R. T.
Published: November 2006

Several ions in the mass spectra of wax esters were related to the molecular structures. Assigned structures of ions were confirmed by deuterium labeling. A simple, direct method for quantititive analyses of mixtures was developed. The method involved a comparison of sets of three ions, RCO2H+, RCO2H2+ and [R′−1]+ from all compounds in the mixture. The method was found applicable for mixtures of unsaturated wax esters after reduction with tetradeuterio hydrazine.
Metabolism of ceramide phosphorylethanolamine, phosphatidylinositol, phosphatidylserine and phosphatidylglycerol by housefly larvae
Authors: Hildenbrandt G. R. , Abraham T. , Bieber L. L.
Published: November 2006

Microsome preparations (40,000–90,000 g sediment) fromMusca domestica, housefly, larvae convert exogenous32P‐labeled phosphatidylinositol, phosphatidylserine and phosphatidylglycerol to the respective lysoglycerophosphatides and, ultimately, to the glycerophosphoryl derivatives. These data, combined with previous results, demonstrate that housefly larvae can convert their normal diacylglycerophosphatides to the respective glycerophosphoryl derivatives. Experiments utilizing exogenous3H‐labeled,32P‐labeled and14C‐labeled ceramide phosphorylethanolamine demonstrate that particulate preparations from housefly larvae convert ceramide phosphorylethanolamine to ceramide, phosphorylethanolamine, sphingosine and fatty acid. The presence of ceramide phosphorylethanolamine phosphohydrolase and ceramidase activity in housefly larvae is consistent with the conclusion that ceramide phosphorylethanolamine is metabolized to ceramide and phosphorylethanolamine and the ceramide is then hydrolyzed to sphingosine and fatty acid. Thus, metabolism of ceramide phosphorylethanolamine by these insects is analogous to the metabolism of sphingomyelin by mammalian systems.
5α‐cholestan‐3β‐ol: High concentration in testis of white carneau pigeon
Authors: Ravi Subbiah M. T. , Kottke Bruce A. , Carlo Ivette A.
Published: November 2006

5α‐Cholestan‐3β‐ol (cholestanol) was isolated from the testes of White Carneau pigeons in the highest concentration thus far reported in any animal tissue. It contributed 26% to 28% of the total sterols (384±29.4 μg cholestanol per gram of wet tissue) in testis, and about 27% of it was esterified. The identity of this stanol was confirmed by AgNO3 thin layer chromatography, gas liquid chromatography and mass spectrometry. Ovaries, liver, plasma and other tissues of this pigeon contained this stanol only to the extent of 2% to 10% of total sterols.
Pristane and other hydrocarbons in some freshwater and marine fish oils
Authors: Ackman R. G.
Published: November 2006

Pristane levels in four commercial freshwater fish oils (alewife, tullibee, maria and sheepshead) were found to be markedly lower (0.0001% or less) than those in marine fish oils (herring, sand launce, cod liver and gray cod liver) selected for comparison on the basis of similar types of depot fat storage (0.008–0.107%). Certain normal alkanes were also identified by gas chromatography. Of these, heptadecane was predominant in all of the freshwater fish oils, but octadecane was more prevalent than heptadecane in three of the marine oils.
Detection of a sebacate contaminant from chloroform
Authors: Holtz R. B. , Swenson P. , Abel Marge , Walter T. A.
Published: November 2006

One of the major contaminants of reagent grade chloroform is identified as a diester of sebacic acid. The contaminant is not present in redistilled chloroform.
Characterization of sterols by gas chromatography‐mass spectrometry of the trimethylsilyl ethers
Authors: Brooks C. J. W. , Horning E. C. , Young J. S.
Published: November 2006

The utility of combined gas chromatography‐mass spectrometry in the analysis and characterization of sterols has been explored. Methylene unit (MU) values and principal mass spectrometric data are presented for trimethylsilyl ethers of 28 sterols, including the major natural sterols. The diagnostic value of the fragmentation of trimethylsilyl ethers of Δ5‐3 β‐hydroxysteroids has been confirmed. Characteristic fragmentations of Δ4‐3 β‐trimethylsilyloxysteroids, and of Δ5,7‐3 β‐trimethylsilyloxysteroids were also found. Location of side‐chain hydroxyl groups is facilitated by the α‐cleavages typical of the trimethylsilyl ethers. Fragmentations of saturated sterols, and of Δ7, Δ8(9) and Δ(14) stenols, are less influenced by trimethylsilyl ether formation, but the derivatives still afford satisfactory mass spectra. The combination of gas chromatographic and mass spectrometric information allows positive identification of any of the sterols examined, whereas application of either technique alone may give inconclusive results.
Human serum α‐1‐lipoprotein patterns revealed by starch gel electrophoresis
Authors: Cohen Louis , Djordjevich Juliana
Published: November 2006

The recognition of different serum α‐1‐lipoproteins patterns was made possible by improved lipoprotein staining and separation methods. Three common and some less common patterns were found. The common α‐1‐lipoprotein patterns, here called S, M and F, were found to differ in their relative frequency in men and women, and to be associated with significantly different serum α‐1‐lipoprotein concentrations.
Uptake of cerebroside, cholesterol and lecithin by brain myelin and mitochondria
Authors: Dobiašová Milada , Radin Norman S.
Published: November 2006

The uptake of emulsified labeled lipids by rat brain myelin and mitochondria was studied. Cerebroside and lecithin uptakes were greatly stimulated by addition of salts, particularly those containing divalent cations. Cholesterol uptake was not influenced by salts. Increasing concentrations of detergent (non‐ionic) were inhibitory. Delipidated membranes took up much less lipid, but pretreatment with lecithin partially restored the ability to take up cerebroside and cholesterol. The lipid uptake appears to be nonenzymatic and appears to depend on the size of the emulsified particles. The possible role of such a phenomenon in membrane formation and maintenance is discussed.
Occurrence ofCis‐6‐hexadecenoic acid as the major component ofThunbergia alata seed oil
Authors: Spencer G. F. , Kleiman R. , Miller R. W. , Earle F. R.
Published: November 2006

An unusual series of monoenoic fatty acids constitutes about 85% of the total acids in seed oil fromThunbergia alata. The major component in the oil,cis‐6‐hexadecenoic acid (82%), is accompanied by the homologous 4‐tetradecenoic (ca. 0.2%) and 8‐octadecenoic (1.8%) acids. Another homologous series is represented by 5‐tetradecenoic (ca. 0.2%), 7‐hexadecenoic (1.8%) and the familiar 9‐octadecenoic (4.4%) acids. Traces (<0.1%) of three other acids, 6‐tetradecenoic and 10‐ and 11‐octadecenoic, are also present along with palmitic (5.8%), stearic (0.6%) and linoleic (2.2%) acids. Some of the monoenoic acids have not previously been known to occur in seed oils.
Wax esters in the cystacanths ofPolymorphus minutus (Acanthocephala)
Authors: Barrett J. , Butterworth P. E.
Published: November 2006

The lipids of the cystacanth of the acanthocephalanPolymorphus minutus have been analyzed. Wax esters constituted nearly 90% of the total cystacanth lipids. The wax ester fraction contained approximately 10% steroid ester; the rest was long chain alcohols C12 to C20, largely saturated, esterified with fatty acids C12 to C22, mostly unsaturated, with C18 predominating. Corresponding quantities of wax esters were not found in the adult parasite. Cholesterol was identified as the only steroid present in the cystacanth.
Association of phospholipid‐cholesterol micelles with rat heart mitochondria: Stimulators and inhibitors
Authors: Dobiasova Milada , Linhart Jaroslav
Published: November 2006

The uptake of emulsified labeled lipids by rat heart mitochondria was studied. Divalent cations greatly stimulated uptake of cholesterol in emulsions containing phospholipids; the effect increased with increasing atomic number. Epinephrine and norepinephrine were also stimulatory. Lipid‐depleted mitochondria were less effective in taking up cholesterol unless lecithin or serum lipids were included in the emulsion. Addition of iodoacetamide did not inhibit uptake, while use of heated mitochondria or extremes of pH augmented lipid uptake. Thus the process appears to be non‐enzymatic. While lecithin emulsions showed no visible change on addition of calcium ions, phosphatidylethanolamine emulsions became turbid and the turbidity was largely removed by addition of heparin. Heparin as well as chondroitin sulfate B and nonionic detergent did inhibit lipid uptake by mitochondria. The possible role of such nonenzymatic lipid uptake in membrane formation and cholesterol accumulation is discussed.
Quantitative determination of heparin released lipoprotein lipase activity in human plasma
Authors: Boberg Jonas
Published: November 2006

A method for quantitative determination of heparin released lipoprotein lipase (LPL) activity has been developed. The importance of standardization of substrate and albumin in the assay system has been investigated. Determination of glycerol release in the assay system has been shown to have advantages compared with titration of fatty acids released. Enzyme plasma samples frozen for four months decreased in activity. The method seemed to be specific for emulsified triglycerides and the LPL activity was 98% inhibited by 1 M NaCl. However, there was a lack of reproducibility of the substrate when different lots were used. Analytical error of the method was approximately 5% and there was good reproducibility.
Factors affecting incorporation of precursors into body constituents: A review of common sense considerations with glycolipids as examples
Authors: Main Burton Robert
Published: November 2006

The dynamics of cellular growth are of prime importance to the biochemist. The dynamic state of lipids can be studied by employing radioactive substrates or stable isotope‐labeled substrates. This paper illustrates major factors which may effect the incorporation of precursor substances into body constitutents. These factors are: (a) age and species; (b) molar size of the body's pool of precursor; (c) metabolic activity of the lipid being synthesized; (d) metabolic pathways; (e) route of administration of the precursor; (f) the nature of the precursor, i. e., molecular size, ionic or nonionic, water soluble vs. lipid solubility, and micelle formation; and (g) the influence of hormones and drugs. The synthesis and turnover of cerebrosides and gangliosides in the rat are used to illustrate these seven factors.
Phospholipid content of human and guinea pig muscle: Post‐mortem changes and variations with muscle composition
Authors: Hof Hildegard , Simon R. Gerald
Published: November 2006

The phospholipid composition of human and guinea pig skeletal muscle was determined. Virtually no autolytic changes occurred in the first half hour post‐mortem and after 12 hr only very small changes were detected. There were significant differences in the phospholipid composition of red and white muscle, especially in the diphosphatidyl glycerol (DPG) content,red muscle having over 50% more DPG than white muscle.
Separation of the C20 unsaturated fatty acids from rapeseed oil by countercurrent distribution
Authors: Haeffner E. W.
Published: November 2006

A C20 fatty acid mixture (5.9 g), which was obtained from fractional distillation of 95 g methyl esters of rapeseed oil, was subjected to countercurrent distribution. This procedure yielded 4.5 g eicosenoic acid (20∶1), 0.4 g eicosadienoic acid (20∶2), and 0.04 g eicosatrienoic acid (20∶3), 4.7%, .42% and .04%, respectively, of the total methyl esters.
Graphic presentation of computer‐derived schlieren lipoprotein data
Authors: Jensen L. C. , Rich T. H. , Lindgren F. T.
Published: November 2006

Computer produced graphs of lipoprotein spectra visually present a large amount of information and greatly facilitate error detection. Data derived from schlieren patterns in the analytical ultracentrifuge are fully corrected to standard conditions allowing valid comparison of serum lipoprotein concentrations and profiles. The computer program is flexible enough to provide appropriate representations for many types of spectra and several possibilities for comparison of data.
Two dimensional thin layer chromatographic separation of polar lipids and determination of phospholipids by phosphorus analysis of spots
Authors: Rouser George , Fleischer Sidney , Yamamoto Akira
Published: November 2006

Separation of polar lipids by two‐dimensional thin layer chromatography providing resolution of all the lipid classes commonly encountered in animal cells and a sensitive, rapid, reproducible procedure for determination of phospholipids by phosphorus analysis of spots are described. Values obtained for brain and mitochondrial inner membrane phospholipids are presented.
Pancreatic lipolysis of some brominated vegetable oils
Authors: Conacher H. B. S. , Hartman D. K. J. , Chadha R. K.
Published: November 2006

Pancreatic lipolysis of several commercially used brominated vegetable oils has shown that although hydrolysis proceeds more slowly, these oils are degraded in a similar way to the common vegetable oils.
Composition of wax esters, triglycerides and diacyl glyceryl ethers in the jaw and blubber fats of the Amazon River dolphin (Inia geoffrensis)
Authors: Ackman R. G. , Eaton C. A. , Litchfield Carter
Published: November 2006

The lower jaw fat of the Amazon River dolphinInia geoffrensis contains 52.8% wax ester, 44.7% triglyceride and 2.5% diacyl glyceryl ether, while its dorsal blubber fat is >98% triglyceride. Examination of the intact lipids, the derived fatty acids and the derived fatty alcohols by gas chromatography reveals that the blubber triglycerides show characteristics of freshwater fish fats, but the jaw fat lipids have several distinctive features. Jaw fat wax esters, triglycerides and diacyl glyceryl ethers are all rich in C10, C12 and C14 fatty acids and contain no polyunsaturated acids. The fatty alcohols in the wax esters are over 90% saturated. The major carbon numbers in the jaw fat triglycerides (C38–C46) are considerably lower than those of the blubber triglycerides (C48–C54). The possible adaptation of the jaw lipids for use in the underwater echolocation process of this dolphin is discussed.