bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of antioxidant deficiency on tissue lipid composition in the rat. I. Gastrocnemius and quadriceps muscle
Authors: Witting L. A. , Horwitt M. K. 
Published: November 2006

AbstractThe gastrocnemius and quadriceps muscle phospholipids of the antioxidant‐deficient rat fed a source of both linoleate and linolenate showed a progressive net increase in arachidonate, a progressive net decrease in all other polyunsaturated fatty acids, and there was a concomitant accumulation of fluorescent pigment of the lipofuscin or ceroid type in the tissue. An increased incorporation of intraperitoneally injected, isotopically labeled acetate into not only arachidonate but also the other higher polyunsaturated fatty acids, was observed. The net loss of the higher polyunsaturated fatty acids from the membrane lipids (presumably via lipid peroxidation) apparently was partially compensated by a homeostatic mechanism which involved conversion of the available precursors, linoleate and linolenate, to the higher polyunsaturated fatty acids. The rates of decrease of the polyunsaturated fatty acids in the muscle phospholipids and accumulation of fluorescent pigment in the tissue were correlated with the rate of production of creatinuria.
cis‐5,cis‐9,cis‐12‐octadecatrienoic and some unusual oxygenated acids inXeranthemum annuum seed oil
Authors: Powell R. G. , Smith C. R. , Wolff I. A. 
Published: November 2006

AbstractSeed oil ofXeranthemum annuum (family Compositae) contains a number of unusual fatty acids in addition to palmitic, stearic, oleic, linoleic and linolenic. These acids includecis‐5,cis‐9,cis‐12‐octadecatrienoic, 5%;cis‐9‐l,10‐l‐epoxyoctadecanoic, 3%;cis‐9‐l,10‐l‐epoxy‐cis‐12‐octadecenoic (coronaric), 8%; andcis‐12‐d,13‐d‐epoxy‐cis‐9‐octadecenoic (vernolic), 2%; as well as a mixture of two hydroxy acids, 11%. The absolute configurations of the two 9,10‐epoxy acids are established for the first time.
Distribution of free and conjugated sterols in orange and tangor juice sacs
Authors: Nagy Steven , Nordby Harold E. 
Published: November 2006

AbstractComparative studies of the sterol composition of four sterol fractions, vis., free sterols, sterol esters, sterol glucosides and esterified sterol glucosides, were conducted on the juice sacs of six varieties of oranges and two tangor varieties. The sterols quantified in each fraction were β‐sitosterol, campesterol, stigmasterol, cholesterol, 24‐ethylidene cholesterol, brassicasterol and 24‐methylene cholesterol. Each variety showed its own intrinsic composition for these sterols in the four sterol fractions.
Stimulation in vitro of galactocerebroside galactosidase by N‐decanoyl 2‐amino‐2‐methylpropanol
Authors: Arora R. C. , Radin N. S. 
Published: November 2006

AbstractAmides resembling ceramide (fatty acyl sphingosine) were synthesized and tested in vitro for their effects on the rat brain β‐galactosidase which hydrolyzes galactosyl ceramide. The N‐decanoyl derivative of 2‐amino‐2‐methyl‐1‐propanol was most effective, giving a 34% stimulation at 0.15 mM concentration and a 60% stimulation at maximal levels. Addition of a hydroxyl group in the 3 position reduced the degree of stimulation, as did increasing or decreasing the length of the fatty acid portion. Omission of the branched methyl group resulted in inhibition instead of stimulation. Kinetic analysis indicates that the stimulator does not affect the binding of substrate to enzyme, but does speed the rate of hydrolytic action. Stimulation was also observed with the cerebrosidase in spleen and kidney. It is suggested that the stimulators act on an enzyme site other than the substrate‐active site.
Further evidence for the interconversion of monophosphoinositides in vivo
Authors: Holub B. J. , Kuksis A. 
Published: November 2006

AbstractThe incorporation of3H‐inositol into the molecular species of rat liver monophosphoinositides was studied as a function of time. At early time intervals following intraperitoneal injection of the tracer, the specific activity of the monoenoic and dienoic species exceeded that of the total and tetraenoic inoisitides by 7‐ and 14‐fold. From 90 min to 9 hr, the specific activity of the unfractionated phosphatide remained nearly constant while the pronounced decrease in activity [of the monoenoic and dienoic subfractions was concomitant with an increase in the radioactivity of the tetraenoic species, as found previously with32P‐ and14C‐glycerol. The present results suggest that the entire glycerophosphorylinositol backbone originally associated with the monoenoic and dienoic monophosphoinositides is converted into tetraenoic species with remarkable conservation of label in vivo.
The effect of sonication on lipase activity
Authors: Goodman L. P. , Dugan L. R. 
Published: November 2006

AbstractStudies were made to evaluate the effect of sonication on activity of porcine pancreatic lipase and on activity of this lipase when in contact with substrate. Lipase was rapidly inactivated by sonication at 50 C, but was stable at 30 C or lower temperatures. Sonication for 4.5 min of lipase and olive oil at 38 C produced 2.7 times as much free fatty acid as without sonication. Hydrolysis of tripalmitin was achieved by sonication of lipase and tripalmitin dissolved in methyl myristate.
The absolute optical configurations of the isomeric 9,10‐epoxystearic, 9,10‐dihydroxystearic and 9,10,12‐trihydroxystearic acids
Authors: Morris L. J. , Crouchman M. L. 
Published: November 2006

AbstractThe absolute optical configuration of (−)‐cis‐9,10‐epoxystearic acid has been verified as being L. Here (−)‐erythro‐9,10‐dihydroxystearic acid, isolated from castor oil, was converted by stereospecific reactions to (+)‐cis‐9,10‐epoxystearic acid and was thereby proved to be D‐9,D‐10‐dihydroxystearic acid. Removal of the D‐12‐hydroxy group from the higher meltingerythro‐9,10,12‐trihydroxystearate derived from ricinoleic acid, after protection of the glycol group, gave the L‐9,L‐10‐dihydroxystearate derivative. This proved the high melting diastereoisomer to be L‐9,L‐10,D‐12‐trihydroxystearate and directly verified the supposition that the higher melting, arsenite‐complexing diastereoisomer of such oxidation pairs has thetrans‐10,12‐diol grouping. On this basis, the higher meltingthreo‐trihydroxystearate from ricinoleate must be D‐9,L‐10,D‐12‐trihydroxystearate and removal of the 12‐hydroxy group must give D‐9,L‐10‐dihydroxystearate which proved to be the levorotatory enantiomer. The dextrorotatory L‐9,D‐10‐dihydroxystearate was transformed by stereospecific reactions to (+)‐trans‐9,10‐epoxystearic acid, thereby defining the absolute configurations oftrans‐9,10‐epoxystearic acids. On the basis of these results conclusions may be drawn as to the stereospecificity and site of action of enzymes which hydrate 9,10‐epoxystearic acids.
The maturation of rat brain myelin
Authors: Eng Lawrence F. , Noble Ernest P. 
Published: November 2006

AbstractMyelin fractions were prepared from brains of 9‐ to 90‐day‐old rats by continuous and discontinuous sucrose density gradient procedures. Total protein and lipid content of myelin showed little variation, but lipid composition changed significantly during maturation. Cholesterol, galactolipids, and ethanolamine glycerophosphatide plasmalogen increased whereas choline glycerophosphatide content decreased with increasing age. The changes in lipid composition were more marked in the myelin prepared by the discontinuous gradient technique. The significance of these lipid changes in relation to their organization in the myelin membrane is discussed.
Quantification of lowered cholesterol oxidation in guinea pigs with latent vitamin C deficiency
Authors: Ginter E. , Nemec R. , Červeň J. , Mikuš L. 
Published: November 2006

AbstractFifty‐two male guinea pigs fed on a scorbutigenic diet were divided into a control group (10 mg ascorbicacid per animal per day) and a group with latent vitamin C deficiency (2 weeks on the scorbutigenic diet only, followed by a maintaining dose of 0.5 mg ascorbic acid per animal per day). After 13 weeks, 26‐14C‐cholesterol was administered intraperitoneally to all the animals, in which the14C excretion in the expired CO2 and the urine and cholesterol specific activity in the blood serum and liver were then studied at intervals of 24 hr and 1, 3, 5, 7, 9 and 11 weeks. The ascorbic acid concentration in the liver and spleen of the control animals was five times higher than in vitain C‐deficient animals. The total cholesterol concentration in serum and liver was significantly higher in the vitamin C‐deficient guinea pigs. A two‐pool analysis of the disappearance curves of serum cholesterol specific activity showed that the size of the cholesterol pool A (blood and tissues with rapid cholesterol exchange) was greater in the vitamin C‐deficient animals. The rate of the transformation of cholesterol to bile acids was estimated as the ratio of14CO2 expired to liver cholesterol specific activity. Latent vitamin C deficiency caused significant slowing down of this process (controls: 11.8±0.6; vitamin C deficiency: 8.3±0.4 mg/24 r/500 g w/w). A significant correlation between the liver ascorbic acid concentration and the rate of cholesterol transformation to bile acids was found. The results demonstrate that ascorbic acid is necessary for a normal course of cholesterol catabolism. In latent vitamin C deficiency, the rate of cholesterol catabolism slows down and cholesterol consequently accumulates in the blood and liver of vitamin C‐deficient guinea pigs.
In vivo incorporation of3H arachidonic acid and14C linoleic acid into liver lipids from essential fatty acid‐deficient rats
Authors: Mercuri Osvaldo , Elena De Tomás Maria 
Published: November 2006

AbstractEssential fatty acid (EFA)‐deficient rats were injected intraportally with a labeled solution containing3H arachidonic acid and14C‐linoleic acid during a 1 min period. Livers were quickly frozen, pulverized, and the lipids extracted and fractioned by thin layer chromatography. The incorporation of3H and14C into liver lipids was measured, and the per cent distribution of radioactivity into the different lipid fractions determined and compared with those previously obtained from normal rats. In contrast with normal rats, ca. 70% of the3H arachidonic acid and14C‐linoleic acid incorporated into total lipids from EFA‐deficient rats was recovered in the phospholipid fraction. From the results of this experiment, it is suggested that a more active deacylation‐reacylation cycle in EFA‐deficiency could be responsible for this increase.
Pentane from thermal decomposition of lipoxidase‐derived products
Authors: Evans C. D. , List G. R. , Dolev Ami , McConnell D. G. , Hoffmann R. L. 
Published: November 2006

AbstractThermal decomposition of 13‐hydroperoxyoctadeca‐9,11‐dienoic acid yields hydrocarbons as part of the scission products. Pentane is formed predominately and to the practical exclusion of all other short‐chain hydrocarbons.
Fatty acid composition of rat hearts as influenced by age and dietary fatty acids
Authors: Szuhaj B. F. , McCarl R. L. 
Published: November 2006

AbstractFatty acid composition of neutral and polar lipid fractions from rat hearts was determined in rats of different ages as their diet source changed. Piebald rats were weaned at 21 days and were fed standard lab chow. Lipids from rat hearts, mothers milk and lab chow were purified on a Sephadex G‐25 fine column and separated into neutral and polar lipid fractions by silicic acid column chromatography. These lipid fractions were then hydrolyzed and methylated with BF3 in methanol, prior to gas liquid chromatographic separation on a 1/8 in. × 10 ft aluminum column of 15% EGS on 80–100 mesh acid‐washed Chromosorb W. Three major fatty acids in the neutral lipid fraction comprised 72% of total neutral lipid fatty acids from young hearts. At sexual maturity (at least 74 days old) C18∶1 was the major fatty acid, followed by C16∶0 and C18∶0. The same three fatty acids comprised 83% of total polar lipid fatty acids, but C18∶0 was the major fatty acid, followed by C16∶0 and C18∶1. The fatty acid composition of dietary lipids influenced the total neutral lipid fatty acid composition of the rat heart, but had little influence on the fatty acid composition of the polar lipid fraction.
Monoethylenic isomers in cardiac lipids of rats fed partially hydrogenated herring oil
Authors: Conacher H. B. S. , Page B. D. , Beare‐Rogers J. L. 
Published: November 2006

AbstractCompositional studies have been carried out to compare the monoethylenic fatty acid isomers of a partially hydrogenated herring oil with those found in the cardiac lipid of young rats fed this oil for 1 or 16 weeks. In general, all geometrical and positional isomers with chain lengths C16, C18, C20 and C22 found in the hydrogenated oil were also observed in cardiac lipid. Evidence was also obtained for the occurrence of β‐oxidation in the catabolism of thecis andtrans isomers of these long chain acids.
Hydrolysis of linoleate geometric isomers byGeotrichum candidum lipase
Authors: Jensen Robert G. , Gordon Dennis T. , Scholfield C. R. 
Published: November 2006

AbstractLipase (EC 3.1.1.3) from the microorganismGeotrichum candidum preferentially hydrolyzescis‐9 18∶1 andcis,cis‐9,12 18∶2 from triacylglycerols, largely ignoring all other positional isomers ofcis 18∶1 as well astrans‐9 18∶1. To obtain additional information about the specificity of the enzyme, two triacylglycerols were prepared and utilized as substrates. The lipase hydrolyzed 85%cis,cis‐9,12 18∶2 and 15%trans,trans‐9,12 18∶2 from the triacylglycerol, containing ca. 50% of each acid. From the triacylglycerol containing 46.3%cis,trans‐9,12 18∶2 and 53.7%trans,cis‐9,12 18∶2, 44.8 and 55.2% of the two acids were hydrolyzed. Therefore the enzyme discriminated against thetrans,trans isomer but not between thecis,trans andtrans,cis isomers.
Liver retinal reductase and oxidase activities in rats exposed to low environmental temperature
Authors: Sundaresan P. R. , Therriault Donald G. 
Published: November 2006

AbstractThe influence of low environmental temperature on retinal reductase and retinal oxidase activities in rat liver was examined after two and four weeks of cold exposure at 5 C. Liver retinal reductase decreased whereas retinal oxidase increased with time in control rats fed a retinol‐free diet, then replenished with retinyl acetate and maintained at 25 C. When rats under identical experimental conditions were exposed to 5 C, the decrease in retinal reductase and increase in retinal oxidase were both found to be greater at 5 C than at 25 C. These results support the hypothesis that increased metabolic rate from exposure of the animal to a cold environment increases the requirement for retinoic acid and decreases the storage of retinol. Even though changes in total liver retinol levels were similar in both groups, an increased utilization of retinol was indicated when the utilization of retinol was expressed as a ratio of total retinol removed from the liver to total weight gain of the animal.
Differences between the metabolism of linoleic and palmitic acid: Utilization for cholesterol synthesis and oxidation to respiratory CO2
Authors: Cenedella Richard J. , Allen Arthur 
Published: November 2006

AbstractMeasurements were made of the incorporation of intragastrically administered 1‐C14‐labeled linoleic and palmitic acid carbon into the total body cholesterol of the intact rat and of the rat's ability to oxidize these two labeled acids to respiratory CO2. As compared with palmitic acid, the intact rat and isolated rat tissues exhibit a greater ability to metabolize linoleic acid. This is evidenced by a greater utilization of linoleic acid carbon for synthesis of total body cholesterol and also by a preference for the oxidation of linoleic acid. The greater incorporation of linoleic acid carbon into cholesterol appears to reflect the preferential oxidation of linoleic acid by the liver, a main site of fatty acid oxidation and cholesterol biosynthesis. This preference of the rat to utilize linoleic acid carbon for the synthesis of cholesterol may help to explain the well documented observation that the plasma cholesterol of the rat increases as the linoleic acid content of the diet increases.
Effect of ethanol on plasma triglycerides in male and female rats
Authors: Hernell Olle , Johnson Owe 
Published: November 2006

AbstractA single large dose of ethanol was given to fasted rats and to rats fed a fat‐free diet containing orotic acid. An increased plasma triglyceride concentration after ethanol feeding was consistently found in fasted male rats, while the results in fasted female rats varied between the experiments. The total rate of triglyceride secretion into the plasma in fasted rats was estimated as the Triton‐induced hypertriglyceridemia 6–7.5 hr after ethanol feeding. The effect of ethanol on the triglyceride secretion from extrahepatic sources was estimated in the same way in rats, with the hepatic triglyceride secretion blocked by orotic acid. Ethanol enhanced the Triton‐induced hypertriglyceridemia in both male and female fasted rats, but to a greater extent in male rats. Ethanol did not stimulate the extrahepatic triglyceride secretion during this period.
On methylating activity of L‐(methyl‐14C)‐methionine in metabolism of phospholipids by insectCeratitis capitata
Authors: Jimenez C. , Municio A. M. , Suarez A. 
Published: November 2006

AbstractThe methylating activity of L‐(methyl‐14C)‐methionine in different stages of development of the insectCeratitis capitata was studied in a series of in vitro and in vivo experiments. Larval and pharate adult homogenates of the insect were used in the in vitro conditions, and the utilization of the methyl group of methionine for the synthesis of different classes of phospholipids was evaluated. Incorporation of radioactivity in lipids by pharate adult homogenates was significantly higher than that by larval homogenates. In both cases, phosphatidyl ethanolamine showed the highest levels of radioactivity incorporation. Free bases from total lipid hydrolysates were resolved and identified by paper chromatography, and the labeling was investigated by radioactivity scanning of paper chromatograms. Significant differences were observed in the activity of both stages of development of the insect. Larval and pharate adult homogenates incorporated mainly the labeled methyl groups into ethanolamine. Monomethyl ethanolamine was the only methyl derivative that appeared in the hydrolysates of lipids synthesized by larval homogenates, whereas mono‐, di‐ and trimethyl ethanolamine clearly were detected in those synthesized by pharate adult homogenates. Administration of L‐(methyl‐14C)‐methionine to larvae confirmed the existence of methylation reactions in the metabolic activity of the insect.
Hydrocarbons from males, females, and larvae of pecan weevil:Curculio caryae (Horn)
Authors: Mody Naresh V. , Hedin Paul A. , Neel William W. , Miles D. Howard 
Published: November 2006

AbstractAs part of a program to identify as many as possible of the components of the pecan weevil,Curculio caryae (Horn), the hydrocarbons from males, females, and larvae were isolated by solvent extraction and column chromatography and subjected to gas liquid chromatographymass spectrometry analysis. n‐Alkanes from C14−C32 in the larvae and unsaturated and branched chain hydrocarbons from C20−C32 in males and females were found. There are no significant differences between the hydrocarbons of the male and female pecan weevils.
Hepatoma, host liver, and normal rat liver phospholipids as affected by diet
Authors: Wood Randall 
Published: November 2006

AbstractIndividual phospholipid classes derived from hepatoma, host liver, and normal liver of rats maintained on chow and fat free diets were examined in detail and the sphingomyelin and phosphoglyceride structures compared. The concentration of hepatoma sphingomyelin was higher while phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, and diphosphatidylglycerol were only one‐fourth to one‐half normal liver concentrations, irrespective of diet. Hepatoma phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol contained higher percentages of 18∶1 and, except phosphatidylinositol, much lower percentages of most polyunsaturated fatty acids than liver. The 1‐position of host liver phosphatidylcholine and phosphatidylethanolamine, normal liver phosphatidylcholine and phosphatidylethanolamine, and hepatoma phosphatidylcholine from animals on both diets had the same approximate fatty acid composition, but the percentage of 16∶0 in hepatoma phosphatidylethanolamine was reduced dramatically. The low percentage of 16∶0 at the 1‐position of both phosphatidylethanolamine and triglycerides suggests that the 1‐position fatty acids of these two classes may have a similar origin. The fat free diet reduced the percentage of 18∶2 in liver diphosphatidylglycerol 3‐fold and the decrease was offset by increased percentages of 16∶1 and 18∶1; whereas the very low percentage of 18∶2 in hepatoma diphosphatidylglycerol was offset by increased percentages of 18∶0 and 16∶0. Liver phosphatidylinositol and phosphatidylcholine from the animals fed the fat free diet contained the highest percentage of 20∶3, which replaced 20∶4. Hepatoma sphingomyelin contained a much higher concentration of 24∶0 and 24∶1 than liver. The hepatoma sphingomyelin also contained a C‐24 dienoic acid, which was not detected in host and normal liver. Host liver contained a higher percentage of 22∶6 than normal liver. The diglycerides derived from host liver PC contained a significantly higher percentage of carbon number 38 than normal liver. Diglycerides derived from hepatoma phosphatidylcholine and phosphatidylethanolamine exhibited a 1‐random‐2‐random distribution of fatty acids, whereas diglycerides from liver phosphatidylcholine and phosphatidylethanolamine showed pairing of specific fatty acids.
Effect of vitamin B12 status on the occurrence of branched‐chain and odd‐numbered fatty acids in the liver lipids of the baboon
Authors: Garton G. A. , Scaife J. R. , Smith A. , Siddons R. C. 
Published: November 2006

AbstractBranched chain fatty acids of the anteiso series and others with methyl substitution nearer to the carboxyl group were found, together with odd numbered, straight chain fatty acids, in very small proportions in baboon liver lipids. The proportions were increased in vitamin B12‐depleted animals, especially after administration of a B12 analogue.
Effect of diet on fatty acids in the lipoprotein cholesteryl esters of type IIa and normal individuals
Authors: Newton R. S. , Pitas R. E. , Jensen R. G. 
Published: November 2006

AbstractFour normal and two individuals with type IIa hyperlipoproteinemia were placed on the National Heart and Lung Institute Type IIa Diet (<300 mg of cholesterol per day, high polyunsaturated, low saturated fat diet) for 1 week and on a normal diet the following week. Plasma samples were obtained and the cholesterol contents of plasma and of very low density, low density and high density lipoproteins determined. The cholesteryl esters in one type IIa and two normal individuals were identified.The cholesteryl esters in type IIa very low density lipoproteins from blood drawn 45 min after the last meal in each dietary period, contained less 18∶2 than from the normal. After the first dietary period, the very low density lipoprotein cholesteryl ester 18∶2 content for the type IIa was 37.2M% and for the normals, 54.7M%. After the second dietary period, the corresponding values were 49.7M% and 56.7M%. Fasting samples had lower 18∶2 contents in the low density lipoproteins from the Type IIa subject following both dietary periods and in the high density lipoproteins following the Type II diet.