bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of long chain fatty acids by subcellular fractions of rat liver: I. Activation oftrans‐unsaturated acids
Authors: Lippel Kenneth
Published: November 2006

The optimal fatty acid to protein ratio for maximum rat liver microsomal or mitochondrial activation of thetrans‐monounsaturated acids elaidate ortrans‐vaccenate is similar to the ratio for maximum palmitate activation but approximately double the optimal ratio for maximum activation of thecis‐unsaturated fatty acids, oleate,cis‐vaccenate, or of thetrans‐diunsaturated linelaidic acid. However, when the substrate is a fatty acid‐albumin complex rather than free fatty acids, optimal fatty acid activation appears to be independent of geometrical configuration or degree of unsaturation. All‐trans retinoate, d‐α‐tocopheryl acid succinate, and dihomogeranoate are not activated themselves, but at low concentrations extensively inhibit activation ofcis‐acids (oleate,cis‐vaccenate, petroselenate, linoleate, linolenate, arachidonate) and thetrans‐diunsaturated linelaidate but do not affect activation of palmitate ortrans‐monounsaturated acids elaidate andtrans‐vaccenate. Anionic, cationic or nonionic detergents in a pH 7.4 buffered incubation medium were shown to inhibit, have no effect on, or apparently activate oleate activation, respectively, while not affecting or inhibiting palmitate and elaidate activation. The effect observed was dependent on the fatty acid to protein ratio, the fatty acid configuration and the detergent concentration.
Molecular species of wax esters in jaw fat of atlantic bottlenose dolphin,Tursiops truncatus
Authors: Ackman R. G. , Sipos J. C. , Eaton C. A. , Hilaman B. L. , Litchfield Carter
Published: November 2006

The jaw fat of the Atlantic bottlenose dolphin (Tursiops truncatus) contains unusual wax esters which can be separated into short chain (C24) fractions by thin layer chromatography. The short chain wax esters (28 wt. %) have been characterized as a 72∶24∶4 mixture of isovaleroyl, isobutoryl, and 2‐methylbutyrol, esters of C14–C18 n‐ and iso‐alcohols. The intact <C24 esters have been resolved into individual molecular species by gas liquid chromatography on open‐tubular polyester columns. The long chain wax esters (12 wt. %) contain C10–C22 n‐ and iso‐acids esterified to the same C14–C18 n‐ and iso‐alcohols. Gas liquid chromatography of the intact, hydrogenated >C24 esters on a short JXR column has characterized them according to carbon number and the number of methyl branches they contain.
Incorporation of acetate into fatty acids and complex lipids of soybean cotyledon slices under aerobic and anaerobic conditions
Authors: Stearns E. M. , Morton W. T.
Published: November 2006

Soybean slices incubated with [1‐14C] acetate in the presence of air synthesized fatty acids to a greater extent than did slices in the absence of air. The proportion of radioactive fatty acids incorporated into the neutral lipid was ca. 35% in the presence or absence of air. However, both the proportion and the absolute amount of radioactive fatty acids in phospholipids were greater in the presence of air. This difference was particularly great in phosphatidic acid and in a minor uncharacterized phospholipid component. Significant incorporation of acetate into monoenoic acids was observed in these two lipids and in phosphatidyl choline. The latter also showed an accumulation of newly synthesized polyenoic acids when air was present. Stearic acid synthesis was greater under aerobic than under anaerobic conditions. The present results support the concept that a relationship exists between the synthesis of unsaturated fatty acids and their incorporation into phospholipids in plants.
Fatty acid positional distribution in egg yolk triglycerides from various avain species
Authors: Couch J. R. , Saloma A. E.
Published: November 2006

The fatty acid composition and distribution in egg yolk triglycerides and phosphatides from the turkey, duck, prairie chicken, bobwhite quail, Japanese quail, and inbred‐hybrid and midget mutant hens were determined after all species had been fed diets of similar fat and fatty acid content for 90 days. Total volk lipids were composed of ca. two‐thirds neutral lipids and one‐third polar lipids. The predominant fatty acids were palmitic and stearic. There were statistically significant differences in the my ristic, palmitic, palmitoleic, linoleic, and linolenic acids in the yolk triglycerides and in the proportion of 16∶1, 18∶0, 18∶2, arachidonic, docosanoic, docosahexaenoic, and tetracosanoic acids in the phosphatides among the various species. Linoleic acid predominantly was linked at the 2‐position in the yolk triglycerides followed by the 20∶4 acid. The 18∶1 acid also was found preferentially at the 2‐position. There was a low level of 18∶2 in the yolk triglycerides and phosphatides from the duck and an especially high level of 20∶4 acid in the phosphatides. The triglycerides in the species studied have essentially the same distribution of fatty acids in the 2‐position. In all the species, the affinity for the fatty acids at the 2‐position is in the following order: 18∶2=20∶4>18∶1 =18∶3>18∶0=16∶1>14∶0>16∶0 Differences observed among the various genera did not appear to follow taxonomic boundaries. The duck has an efficient system for converting 18∶2 into 20∶4 by elongation and desaturation. The prairie chicken apparently has a high requirement for 18∶2 but an inadequate system for its conversion into 20∶4.
Regulatory function of mitochondria in lipogenesis
Authors: Harris Robert A. , Leland Michael C. , Mahoney Joan Munroe , Mapes James P.
Published: November 2006

A cell‐free system, consisting of particle‐free rat liver cytoplasm plus purified mitochondria, was used to study the synthesis of fatty acid from14C‐U‐alanine. Incorporation of label into lipid was dependent upon the presence of both cytoplasm and mitochondria. However, the metabolic state of the animal, prior to sacrifice, determined the capacity of various mitochondrial preparations to reconstitute the system. Mitochondria prepared from the livers of starved, fat‐fed, or alloxan‐diabetic rats failed to support fatty acid synthesis to the same extent as mitochondria prepared from control animals. Likewise, less14CO2 was produced in the system reconstituted with liver mitochondria prepared from starved rats. Possible mechanisms are discussed.
Stimulation of ion transport by phosphoglycerides
Authors: Harris Robert A. , Farmer Barbara
Published: November 2006

Phosphoglyceride extracts of beef heart mitochondria stimulated the transport of cations and “permeable” anions across a membrane barrier of chloroform in a U‐tube. Neutral lipids fractionated from total lipid extracts of heart mitochondria were essentially void of transport activity. Remarkable differences were noted between the capacity of the various phospholipids to support transport of ions in the U‐tube system.
Metabolism of 1,2‐(1‐14C) dipalmitoyl phosphatidylcholine in the developing brain
Authors: Dhopeshwarkar G. A. , Subramanian Carole , Mead James F.
Published: November 2006

Thirteen‐day‐old rats were divided into two groups; one group received 1,2‐(1‐14C) dipalmitoyl phosphatidylcholine and the other 1‐14C palmitic acid in the form of an intraperitoneal injection. One half of the total number of rats in each group was sacrificed 24 hr after injection, and the other half was allowed to survive for 17 days after the injection. Radioactivity incorporated into brain and liver total lipids and into individiual polar lipid components of the brain was determined at both intervals. Phosphatidylcholine was isolated and partially deacylated with phospholipase A2 fromCrotalus Admanteus venom. The ratio of radioactivity FA 2/FA 1 (fatty acid attached to 2 and 1 carbon of the glycerol moiety) 24 hr after the injection was 8.3, when the tracer was radioactive phosphatidylcholine, compared to only 0.7 when radioactive palmitate was injected. From this different labeling ratio and different pattern of labeling the polar lipid components, it was concluded that the radioactive phosphatidylcholine was not deacylated completely before being taken up directly into the brain. Possibilities are discussed to show that the observed radioactive ratio could result from direct uptake of intact phosphatidylcholine, with little or no restriction from the blood brain barrier system, followed by partial degradation by phospholipase A1 in the brain itself.
Fatty acid concentrations in synchronous cultures ofChlorella pyrenoidosa, grown in the presence and absence of glucose
Authors: Reitz Ronald C. , Hamilton James G. , Cole Francis E.
Published: November 2006

Total cellular fatty acids, of a high‐temperature strain ofChlorella pyrenoidosa, were measured during a synchronous growth cycle in continuous light in the presence and absence of glucose.

The fatty acid composition, consisting of saturated monoenoic, dienoic, and trienoic C16 and C18 fatty acids, remained essentially the same whether or not the cells were grown on glucose.

Nearly all of the fatty acids increased irregularly in concentration during the growth cycle, showing a periodism during the prenuclear and cell‐division stages of growth. Cultures exposed to glucose showed a more pronounced drop in the concentration of most of the fatty acids during both stages.

None of the fatty acid concentrations, some of which have been implicated in the Hill reaction of a number of photosynthetic organisms, reflected the periodism in photosynthetic activity which was previously observed during the synchronous growth cycle of this organism.

The changes in fatty acid concentration are discussed with relation to concurrent metabolic and cytological changes during cell maturation in this organism.
Digestion of butyrate glycerides by pancreatic lipase
Authors: Sampugna J. , Quinn J. G. , Pitas R. E. , Carpenter D. L. , Jensen R. G.
Published: November 2006

The racemic triglycerides, glyceryl‐1‐palmitate‐2,3‐dibutyrate (PBB), glyceryl‐1‐butyrate‐2,3‐dipalmitate (PPB), glyceryl‐2‐butyrate‐1,3‐dipalmitate (PBP), and the diglyceride, racemic glyceryl‐1‐palmitate‐3‐butyrate (P‐B) were synthesized and digested with pancreatic lipase. Each triglyceride was mixed with equimolar amounts of triolein (OOO) prior to incubation.

The following order of digestion rates was observed: PBB>PPB>PBP>P‐B. There was no evidence for short‐chain fatty acid specificity; however the triglycerides containing butyric acid were hydrolyzed more rapidly than OOO. Based upon the fatty acid composition of partial glycerides, digestion of butyrate glycerides was not a simple phenomenon. For example, in the digestion of PBB, butyric acid accumulated faster than palmitic acid in the diglycerides, and monobutyrin was found to accumulate when the diglyceride, P‐B, was digested. As evidenced by the fatty acid composition of the monoglycerides, positional specificity of pancreatic lipase was always maintained.
Human placental lipid metabolism. III. Synthesis and hydrolysis of phospholipids
Authors: Robertson Alex , Sprecher Howard
Published: November 2006

Both diacyl GPC (glycerylphosphorylcholine) and diacyl GPE (glycerylphosphorylethanolamine) are synthesized in human placental tissue from their respective monoacyl precursors. The origin of the monacyl phosphatides is apparently not the result of placental phosphatide acyl‐hydrolase activity. The most likely source is maternal serum. The declining level of 1‐acyl GPC in maternal serum is not attributable to lysophosphatide acylhydrolase activity and is probably explained by placental utilization for the synthesis of diacyl GPC.
Inhibition by cyclopropene fatty acids of the desaturation of stearic acid in hen liver
Authors: Allen E. , Johnson A. R. , Fogerty A. C. , Pearson Judith A. , Shenstone F. S.
Published: November 2006

The mechanism of the hardening of body fats of animals by dietary lipids which contain cyclopropene fatty acids has been studied. Dietary methyl sterculate increased the stearic acid content of egg yolk lipid and decreased the activity of the stearic acid desaturase system of hen liver. The cyclopropene fatty acids were specific inhibitors of the stearic acid desaturase system of hen livers since other fatty acids, including two possible metabolites of sterculic acid, failed to inhibit the system at equivalent concentrations. Sterculic acid was a more effective inhibitor of the system than malvalic acid. Kinetic studies have shown that the inhibition is irreversible. Apparent kinetic constants were determined for the system.

The results support the hypotheses that cyclopropene fatty acids inactivate an essential component of the desaturase system, probably by combination with‐SH groups, and that this inhibition causes many of the effects of dietary cyclopropene fatty acids, including permeability disorders of eggs.
Plasma lipid and glucose levels in the adrenalectomized rat following triglyceride ingestion
Authors: Lenz Paul H. , Fleischman Alan I. , Hayton Thomas
Published: November 2006

Adrenalectomy did not significantly alter plasma cholesterol, triglycerides and phospholipids in fasted naturally hypertriglyceridemic rats. Oral administration of cottonseed oil resulted in elevations in plasma cholesterol and phospholipids within 2 hr. Adrenalectomy negated these elevations. Triglycerides rose to an equal extent in both groups at the same time. A secondary rise in plasma glucose was noted at about 7 hr in the control rats; this rise was also negated by adrenalectomy.
Formation of diglycerides of long turnover time from labeled acetate and glucose in rat tissues
Authors: Herodek Sándor
Published: November 2006

Rat adipose tissue pieces were incubated with acetate‐2‐14C and glucose‐14C(U), respectively, and liver slices with acetate‐2‐14C. The labeled tissues were then reincubated in inactive medium, and the changes of radioactivity in the different lipid classes were determined. In all three experiments a significant amount of radioactivity was incorporated in the diglycerides. During 1 hr of reincubation in inactive medium the radioactivity of diglycerides decreased from 35 to 26% of the total lipid activity in the adipose tissue labeled with acetate. In the adipose tissue labeled with glucose radioactivity fell from 25 to 19%. In liver slices 11% of the labeled acetate was incorporated in the diglycerides, and during the 2 hr of reincubation this value fell to its half. The radioactivity of the uniformly labeled glucose was distributed equally in the fatty acids and the glycerol. The distribution of radioactive glycerol between diglycerides and triglycerides was similar to that of the labeled fatty acids. Triglyceride synthesis seems to always be accompanied by the formation of diglycerides with a lastint turnover time.
Dietary lipid, fatty acid synthesis and cholesterol metabolism in aging rats
Authors: Dupont Jacqueline , Mathias Melvin M. , Cabacungan Nenita B.
Published: November 2006

Male and female rats were fed diets containing 2% of calories as corn oil or that plus 40% of calories as beef tallow or corn oil. After 3, 6, 12 and 18 months groups were given 4‐14C‐cholesterol ip, and feces were collected for 9 days. Just prior to necropsy3H‐acetate was administered ip. Samples of serum, liver, heart and carcass were obtained for analysis. Concentrations of fatty acids and cholesterol, synthesis of those and recovery of ring‐labeled steroid are reported. Mortality from acute respiratory disease was very high in male rats fed beef tallow or low fat diets and very low in those fed the corn oil diet. In females, only beef tallow diet resulted in a high mortality rate, and this was lower and at a later age than in males. The most notable effects of age were in relation to fatty acid synthesis and presence of14C‐acidic steroid in the carcass. In 3‐month‐old rats both fats depressed fatty acid synthesis in comparison to the low fat diet. At later ages beef fat ceased to depress fatty acid synthesis in both sexes. Corn oil continued to depress fatty acid synthesis up to 12 months in males and 18 months in females. The presence of14C‐acidic steroid in carcass was substantial in 6‐month‐old rats and constituted ca. 40% of recovered14C in 18‐month‐old rats. The possibility that the increase in acetate incorporation into fatty acids with age in fat feeding is related to chain elongation rather than de novo synthesis is discussed. Both the presence and amount of acidic steroid in the carcass are notable and may be of importance in constructing models of cholesterol turnover.
Health physics practices in laboratories using3H‐ and14C‐labeled tracers
Authors: Berger J. D. , Cloutier R. J.
Published: November 2006

Tritium and14C are often considered relatively safe radionuclides to handle because their permissible body‐burdens are orders of magnitude greater than those for most radionuclides. This is reflected in the U.S. Atomic Energy Commission regulations that do not require a license for the use of amounts up to 1000 μCi of3H and 100 μCi of14C. Although many tracer studies are performed with much smaller quantities, poor control of even these small amounts can result in contamination, causing an internal radiation hazard or the loss of valuable experimental data. This paper discusses the methods of handling radioactive materials that minimize the risks of contamination, and it emphasizes the needs for proper storage, secondary containers, monitoring air and surfaces, and analysis of bioassay samples for measuring body burdens. The user's responsibilities for licensing, waste disposal and transportation are also included. The authors' experience at a laboratory handling both tracer and curie amounts of14C and3H required for labeling and synthesizing compounds and methods of accident prevention and decontamination are described.
Acyl migration solid phase isomerization of 1,2‐diglycerides to 1,3‐isomers
Authors: De Groot W. Th. M.
Published: November 2006

In mixtures of 1,2‐ and 1,3‐diglycerides stored some degrees below their melting points, a rather rapid isomerization of almost all the 1,2‐ diglycerides to the 1,3‐isomers occurred. This solid‐phase isomerization leads to a substantial increase in the yield of saturated and unsaturated mono‐ and mixed‐acid 1,3‐diglycerides.
The triglyceride composition of 17 seed fats rich in octanoic, decanoic, or lauric acid
Authors: Litchfield Carter , Miller Earline , Harlow R. D. , Reiser Raymond
Published: November 2006

Seed fats of eight species ofLauraceae (laurel family), six species ofCuphea (Lythraceae family), and three species ofUlmaceae (elm family) were extracted, and the triglycerides were isolated by preparative thin‐layer chromatography. GLC of the triglycerides on a silicone column resolved 10 to 18 peaks with a 22 to 58 carbon number range for each fat. These carbon number distributions yielded considerable information about triglyceride compositions of the fats.

The most interesting finding was withLaurus nobilis seed fat, which contained 58.4% lauric acid and 29.2–29.8% trilaurin. A maximum of 19.9% trilaurin would be predicted by a 1, 2, 3‐random, a 1, 3‐random‐2‐random, or a 1‐random‐2‐random‐3‐random distribution of the lauric acid3. This indicates a specificity for the biosynthesis of a simple triglyceride byLaurus nobilis seed enzymes.Cuphea lanceolata seed fat also contained more simple triglyceride (tridecanoin) than would be predicted by the fatty acid distribution theories.
Decomposition of unsaturated fatty acid hydroperoxides by hemoglobin: Structures of major products of 13L‐hydroperoxy‐9,11‐octadecadienoic acid
Authors: Hamberg Mats
Published: November 2006

13L‐Hydroperoxy‐9,11‐octadecadienoic acid was decomposed rapidly in the presence of hemoglobin. The product consisted of five major compounds, i.e. 13‐keto‐9,11‐octadecadienoic acid, 13L‐hydroxy‐9,11‐octadecadienoic acid,erythro‐11‐hydroxy‐12,13‐epoxy‐9‐octadecenoic acid,threo‐11‐hydroxy‐12,13‐epoxy‐9‐octadecenoic acid, and 9DL‐hydroxy‐12,13‐epoxy‐10‐octadecenoic acid.
Identification of β‐sitosterol, campesterol, and stigmasterol in human serum
Authors: Govind Rao M. K. , Perkins E. G. , Connor William E. , Bhattacharyya Ashim K.
Published: November 2006

The presence of 3 plant sterols, β‐sitosterol, campesterol, and stigmasterol, has been demonstrated in the serum from 2 patients with β‐sitosterolemia and xanthomatosis.
Phospholipase C catalyzed formation of sphingomyelin‐14C from lecithin and N‐(14C)‐oleoyl‐sphingosine
Authors: Kanfer Julian N. , Spievlogel Christine H.
Published: November 2006

Commercial preparations ofClostridium perfringens were incubated with phosphatidyl choline and N‐1‐(14C) oleoylsphingosine. A radioactive product was formed which cochromatogramed with sphingomyelin standard in three different solvent systems. Several other phospholipases and phosphatases were unable to catalyze this reaction. Neither choline, phosphoryl choline, cytidine diphosphate choline nor p‐nitrophenyl phosphoryl choline were active donors. Sphingomyelin was only slightly active as a phosphoryl choline donor.
Biosynthesis and structure of glycosyl diglycerides, steryl glucosides, and acylated steryl glucosides
Authors: Elbein A. D. , Forsee W. T. , Schultz John C. , Laine Roger A.
Published: November 2006

A particulate enzyme fraction fromMycobacterium smegmatis catalyzed the transfer of14C‐glucose from UDP‐14C‐glucose into neutral glycolipids. The two major radioactive components were purified by column chromatography on 0‐diethylamino ethyl cellulose (acetate) and thin layer chromatography on silica gel in several solvents. The first product yielded a water‐soluble component upon saponification, which had a hexoseglycerol ratio of 1∶1 with all of the hexose being identified as glucose. The second product yielded a water‐soluble component upon saponification which contained hexose and glycerol in a 2∶1 ratio and, in addition to glucose, contained lesser amounts of mannose and galactose. Palmitate and oleate were the predominant fatty acids and were present in equimolar amounts. The products thus have been identified as monoglycosyldiglyceride and diglycosyldiglyceride. The diglycosyldiglyceride could also be labeled with14C‐galactose when UDP‐14C‐galactose served as the donor, but the monoglycosyldiglyceride was only slightly labeled with14C‐galactose. Membrane fractions from mung bean seedlings catalyzed the transfer of14C‐glucose from UDP‐14C‐glucose into a neutral glycolipid which has been purified by thin layer chromatography and analyzed by combined gas liquid chromatographymass spectrometry. It was determined to be a steryl glucoside with the two major sterol components being β‐sitosterol and stigmasterol linked to β‐D‐glucose. Particulate fractions from developing cotton fibers also catalyzed the formation of steryl glucosides and, in addition, they catalyzed the esterification of steryl glucosides at the 6 position of glucose with fatty acids (primarily palmitate and oleate) from an endogenous acyl donor. Both the glucosyl transferase and the acyltransferase have been solubilized with Triton X‐100 and partially purified by chromatography on Sephadex G‐200. The acyltransferase activity was reconstituted by the addition of the steryl glucoside and a phospholipid acyl donor.
Oxidative desaturation of α‐linolenic, linoleic, and stearic acids by human liver microsomes
Authors: De Gómez Dumm Irma N. T. , Brenner Rodolfo R.
Published: November 2006

The desaturation of stearic, linoleic, and α‐linolenic acids by human liver microsomes were studied. The microsomes were isolated from liver biopsies obtained during operations. It was shown that human liver microsomes are able to desaturate 1‐14C‐α‐linolenic acid to octadeca‐6,9,12,15‐tetraenoic acid; 1‐14C‐linoleic acid to γ‐linolenic acid; and 1‐14C‐stearic acid to oleic acid in the same system described in the rat. However, the desaturation activity obtained was low compared to other mammals. This effect was attributed to fasting, premedication, or the anaesthesia.
Effect of acute dietary alteration upon intestinal lipid synthesis
Authors: Mansbach Charles M.
Published: November 2006

The specific activities of three enzymes engaged in complex lipid synthesis, diglyceride acyltransferase, cholinephosphotransferase, and lysolecithin acyltransferase were studied in intestinal mucosa of hamsters fed either saline, hydrolyzed casein, or corn oil for 9 1/2 hr. In the most proximal intestine, saline feeding was associated with a reduced specific activity in villous tips with all three enzymes studied when compared with the two caloric supplemented groups. In the most distal intestine, oil feeding increased the activity of lysolecithin acyltransferase and choline phosphotransferase twofold as compared to casein fed hamsters; diglyceride acyltransferase was increased one‐ and one‐half‐fold. The response of lysolecithin acyltransferase and diglyceride acyltransferase to fat feeding was incomplete when compared to hamsters fed a fat supplemented diet for 7 days, suggesting that their pattern of response to dietary substrate was similar to the disaccharidases. By contrast, the response of cholinephosphotransferase to fat feeding was complete at 24 hr, suggesting that it responds in a manner similar to the glycolytic enzymes.
Purification and properties of aortic cholesteryl ester hydrolase
Authors: Kothari Himinshu V. , Kritchevsky David
Published: November 2006

The enzyme(s) present in acetonedried powder of rat and rabbit aortas, which catalyzes the synthesis and hydrolysis of cholesteryl ester, was purified partially by acid precipitation, acetone fractionation, 0‐(diethylaminoethyl) cellulose chromatography, and Sephadex G‐100 filtration. The synthetic activity was purified by 120‐fold (rat) and 140‐fold (rabbit). Purification of hydrolytic activity was 90‐fold (rat) and 103‐fold (rabbit). Cholesteryl ester hydrolase activity was separated from nonspecific, esterase by column chromatography. Both synthetic and the hydrolytic activities are apprently the functions of one enzyme. The mol wt of the enzyme was estimated to be 140,000 dalton as determined by Sephadex G‐200 gel filtration. The extracts of the acetone‐dired powders of aortas of both species contained an inhibitor of synthetic activity. The inhibitor was nondialyzable and was precipitated at pH 5.7 Both activities were found to be fairly nonspecific with regard to sterol and fatty acids. With oleic acid, the relative rates of sterol ester synthesis were: cholesterol, 100; cholestanol, 94; desmosterol, 35; corprostanol, 24; ergosterol, 20; and β‐sitosterol, 19. Epicholesterol was not esterified. Oleic acid was most active in cholesteryl ester synthesis, the relative rates being: oleic>linoleic>arachidonic>palmitic>stearic>butyric. The rate of hydrolysis was maximum with cholesteryl linoleate followed by oleate, linolenate, palmitate, stearate and laurate in decreasing order.
Effect of temperature upon linolenic acid level in wheat and rye seedlings
Authors: Farkas Tibor , Déri‐Hadlaczky Éva , Belea Adonisz
Published: November 2006

The fatty acid composition, of leaves of nine wheat and one rye species was studied in relation to temperature both under laboratory and field conditions. Seedings exposed to cold (2 C) either in laboratory or on fild had higher levels of linolenic acid in their lipids than their greenhouse (22 C) germinated controls. The increase of the level of linolenic acid was accompanied by a decrease in the level of linoleic acid in field grown species. A relationship seems to exist between sensitivity to cold and accumulation of linolenic acid; those species resistant to cold displayed greater increase in their linolenic acids than those more sensitive to chilling temperatures. This response in cold resistant species was quite rapid, two days of cold exposure resulted in a significant increase of linolenic acid. The possible mechanisms responsible for the observed changes are discussed.
Isolation of a pure isomer of linoleic acid hydroperoxide
Authors: Gardner H. W.
Published: November 2006

A mixture of positional isomers of linoleic acid hydroperoxide was produced from the oxidation of linoleic acid by lipoxygenase from corn or soybean. Chromatography on a column of silicic acid separated 13‐hydroperoxy‐11,9‐octadecadienoic acid in 99+% purity from the mixture obtained by soybean lipoxygenase oxidation of linoleic acid. Attempts at isolation of pure 9‐hydroperoxy‐10,12‐octadecadienoic acid from hydroperoxides obtained by corn lipoxygenase oxygenation of linoleic acid were partially successful with isolation of the 9‐hydroperoxide in 97% purity.
Identification of wax esters inTetrahymena pyriformis
Authors: Wheeler Marcia Anne , Holmlund Chester E.
Published: November 2006

Wax esters, isolated fromTetrahymena pyriformis, have been found to contain 45% branched chain alcohols and 76% branched chain fatty acids. No esters of tetrahymanol or of sterols were found.
In vitro studies on interaction of rat pancreatic lipase and colipase with biliary lipids
Authors: Lairon D. , Nalbone G. , Domingo N. , Lafont H. , Hauton J. , Julien R. , Rathelot J. , Canioni P. , Sarda L.
Published: November 2006

Lipase and colipase were prepared separately from rat pancreatic juice, and their respective interaction with biliary lipids was investigated by gel filtration on agarose in the presence of a micellar solution of sodium taurocholate. It was found that the cofactor can associate with the biliary lipids, whereas the enzyme forms a high mol wt complex only in the presence of colipase. It is suggested that biliary phospholipids might participate in the in vivo formation of the enzyme‐cofactor substrate complex at the triglyceride‐water interface in the presence of bile salts.
The lactone precursor in fresh milk fat: Identification of the hydroxy fatty acids
Authors: Jane Wyatt C. , Pereira R. L. , Day E. A.
Published: November 2006

A series of hydroxy fatty acids was identified from a polar glyceride milk‐fat fraction. These acids were identified as trimethylsilyl (TMS) ether methyl ester derivatives. Identification was achieved by mass spectral analysis and comparison of gas chromatographic retention times with authentic compounds. Mass spectral fragmentation patterns of the TMS ether methyl esters were obtained, and correlation of important ions for structural identifications were made. In addition, semiquantitative data are presented.
The renal phospholipid composition of choline‐deficient rats
Authors: Fewster Mona E. , Hall Michael O.
Published: November 2006

The base composition of the phospholipids involved in the N‐methylation pathway for the biosynthesis of phosphatidyl choline was determined in normal and severely hemorrhagic rat kidneys. There was a decrease in the proportion of phosphatidyl choline and phosphatidyl ethanolamine in the renal total lipids. The significant decrease of phosphatidyl ethanolamine in the kidney phospholipids appears to implicate this phospholipid to a greater extent than phosphatidyl choline in the etiology of the hemorrhagic syndrome.
Identification and composition of turnip root lipids
Authors: Lepage Marius
Published: November 2006

Two varieties of turnip, Laurentian and Wye, were examined for their lipid and fatty acid composition. Lipids extracted with 80% ethanol contained variable quantities of phosphatidic acid, which was considered to be an artifact. Crude lipids were fractionated by TLC, and fatty acids and sterols were analyzed by GLC. Among the common phospholipids, cardiolipid and phosphatidyl glycerol were abundant components. Linolenic acid comprised 60% of the total fatty acids. β‐Sitosterol was the principal sterol, and about half of the carotenoids was lycopene. No great differences between the two varieties studied were observed however.
Specific formation of arachidonoyl phosphatidylinositol from 1‐acyl‐sn‐glycero‐3‐phosphorylinositol in rat liver
Authors: Holub B. J.
Published: November 2006

The conversion of 1‐acyl‐sn‐glycero‐3‐phosphorylinositol‐3H into phosphatidylinositol‐3H was studied using rat liver microsomal and homogenate preparations. The nature of the molecular species of phosphatidyl inositol so formed in the absence of added acyl moieties was determined after fractionating the radioactive product by means of argentation thin layer chromatography. In other experiments, the possible specificity of the microsomal acyl‐CoA:1‐acyl‐sn‐glycero‐3‐phosphorylinositol acyltransferase towards different acyl‐CoA derivatives was investigated. Maximum conversion of 1‐acyl GPI to the diacyl analogue was dependent on the addition of adenosine triphosphate and CoA when exogenous acyl groups were omitted from the incubation medium. Under these latter conditions, the tetraenoic species comprised 56–74% of the total molecular species of newly‐formed phosphatidylinositol. The microsomal acyl‐CoA:1‐acyl‐sn‐glycero‐3‐phosphorylinositol acyltransferase showed a marked preference for arachidonoyl‐CoA. The present results suggest that the enrichment of rat liver phosphatidyl inositol in arachidonic acid may arise when 1‐acyl‐sn‐glycero‐3‐phosphorylinositol is acylated to form phosphatidylinositol.
Effect of cold stress on rapeseed oil fed rats
Authors: Hulan H. W. , Kramer J. K. G. , Mahadevan S. , Sauer F. D. , Corner A. H.
Published: November 2006

No mortality was observed in 6 week old male Sprague‐Dawley rats subjected to cold at 4 C for 3 weeks and fed either a control diet (Chow) or a semisynthetic diet containing 20% by wt rapeseed oil high in erucic acid (23.6%). All rats fed the Chow diet and 17 of 20 rats fed the rapeseed oil‐containing diet survived 4 weeks in the same environment. Three rats on the latter diet died of self‐mutilation. Marked myocardial lipidosis as well as a large accumulation of 20∶1 and 22∶1 was observed in the hearts of rats fed the rapeseed oil‐containing diet. Five of 20 rats on the Chow diet and 2 of 20 rats on the rapeseed oil‐containing diet had focal necrotic areas in the myocardium.
Neutral lipid composition ofCulex quinquefasciatus andCulex tritaeniorhynchus cells at two phases of growth
Authors: Yang T. K. , McMeans E. , Anderson L. E. , Jenkin H. M.
Published: November 2006

The mosquito cellsCulex quinquefasciatus andCulex tritaeniorhynchus were grown in spinner cultures. The fatty acid profiles of the neutral lipid classes were analyzed, and comparisons were made between the two species at logarithmic and stationary phases of growth and between the species and the medium. The results from the data suggest an increase in the average chain length of the fatty acids in the free fatty acid and sterol ester fractions of theCulex quinquefasciatus cells with aging. From the logarithmic to stationary phase, both Culex cells showed some increase in desaturation of acids in the di‐ and triglyceride and free fatty acid fractions. TheCulex tritaeniorhynchus cells also showed some increase in desaturation of acids in the monoglyceride fraction. Differences between the twoCulex species at the logarithmic phase of growth were observed in the fatty acid profiles of all the neutral lipid fractions examined and at the stationary phase of growth in the free fatty acid, triglyceride, and sterol ester fractions.
Cholesterol and fatty acid synthesis in swine
Authors: Huang William Y. , Kummerow Fred A.
Published: November 2006

In incubation studies with swine tissue slices, acetate‐1‐14C or glucose‐U‐14C as substrates were incorporated more readily into fatty acids and cholesterol in adipose tissue than other tissues tested. Cholesterol and fatty acid synthesizing activity was substantial in the small intestine. When acetate was available, liver, small intestine, and adipose tissue were important sites for cholesterol synthesis. Heart and aortic tissue had marginal levels of cholesterol synthesizing ability. Lipogenesis in adult swine liver, heart, and aortic tissue was extremely low. As in tissue slices, incorporation of acetyl‐1‐14C CoA into fatty acids by adipose homogenates indicated high lipogenic activity. Subcellular fractionations of heart and aortic tissue indicated that the heart microsomal fraction had the highest lipogenic activity as measured by the incorporation of acetyl‐1‐14C CoA into fatty acids. In adult swine adipose tissue, the incorporation of glucose‐U‐14C into fatty acid was higher than its incorporation into glyceride‐glycerol. The synthesis of glyceride‐glycerol from glucose‐U‐14C or acetate‐1‐14C in liver was higher than for fatty acid synthesis. The activity of acetyl CoA carboxylase, fatty acid synthetase, citrate cleavage enzyme, nicotinamide adenine dinucleotide phosphate‐malate dehydrogenase, glucose‐6‐phosphate dehydrogenase, and 6‐phosphogluconate dehydrogenase was considerably higher in adipose tissue than in other tissues tested, paralleling its high lipogenic capacity.
Monocarboxylic acids from oxidation of acyclic isoprenoid alkanes byMycobacterium fortuitum
Authors: Cox R. E. , Maxwell J. R. , Myers R. N.
Published: November 2006

Mycobacterium fortuitum utilizes certain stereoisomeric mixtures of individual multimethyl branched alkanes as sole carbon source, including 2,6(R), 10(S), 14 (RS)‐tetramethylhexadecane; 2,6(R),10(S),14(RS)‐tetramethylheptadecane; 2,6(RS),10(RS)‐trimethyltetradecane, and 2,6(R),10(S)‐trimethylpentadecane. Products of oxidation isolated from the bacterial lipids were acids derived predominantly from oxidation of the isopropyl terminus of each alkane, except in the case of 2,6(RS),10(RS)‐trimethyltetradecane. With the latter, acids from oxidation at either terminus were detected in comparable proportions.
Clinical evaluation of MK‐185: A new hypolipidemic drug
Authors: Sirtori Cesare , Hurwitz Aryeh , Sabih Khalid , Azarnoff Daniel L.
Published: November 2006

A double‐blind crossover study in 11 patients suggests that MK‐185 may be a useful drug in lowering plasma triglyceride levels, whereas it has minimal effects on cholesterol levels. A good correlation between the hypouricemic and protein bound iodine lowering effects and plasma level of MK‐185 was seen. No correlation with the hypolipidemic effect was noted.
A review of studies on the mode of action of clofibrate and betabenzalbutyrate
Authors: Fallon Harold J. , Adams Larry L. , Lamb Robert G.
Published: November 2006

Clofibrate and betabenzalbutyrate produce a variety of metabolic alterations in vivo. These include reduction in serum triglyceride and alterations in adipose tissue uptake and release of lipids. Clofibrate displaces thyroxine from albumin binding sites and produces an enlargement of liver and changes in ultrastructure. The biochemical changes produced by clofibrate include reduction in adenyl cyclase activity, inhibition of acetyl CoA carboxylase, inhibition of cholesterol biosynthesis and inhibition of triglyceride formation. Recent studies in this laboratory have shown that the inhibition of hepatic triglyceride formation is an early metabolic consequence of clofibrate administration and precedes the fall in serum triglyceride and several of the other biochemical alterations. Moreover clofibrate and betabenzalbutyrate inhibit the esterification ofsn‐glycerol‐3‐P by rat liver homogenate and microsomal preparations. The initial step in this pathway, acyl‐CoA‐sn‐glycerol‐3‐P acyltransferase, is inhibited by both drugs, in vitro. It is possible that this in vitro inhibition explains the early hypotriglyceridemic effect of these agents.
Inhibition of the plasma lecithin‐cholesterol acyltransferase reaction by hydrogen peroxide and peroxidized lecithin
Authors: Mickel Hubert S. , Foulds Emmett L. , Clark Dale A.
Published: November 2006

Inhibition of the plasma lecithincholesterol acyltransferase reaction by hydrogen peroxide and peroxidized lipids was studied by two methods: a radiochemical tracer technique and a direct colorimetric assay. Protection of sulfhydryl groups withp‐chloromercuribenzoate, prior to exposure to peroxide, resulted in restoration of acyltransferase activity on removal of the inhibitors with mercaptoethanol. On the basis of these observations, it is proposed that lipid peroxides inhibit the plasma lecithin‐cholesterol acyltransferase reaction by alteration of sulfhydryl groups necessary for enzymatic activity.
Inhibition of cholesterol synthesis by β‐benzal butyric acid and derivatives
Authors: Porcellati G. , Giorgini D. , Toja E.
Published: November 2006

Cholesterol biosynthesis has been examined using rat liver slices in vitro from 2‐14C‐acetate and 2‐14C‐mevalonate, in the presence of β‐benzal butyric acid (BBA) and its metabolite, α‐hydroxy β‐benzal butyric acid (HBBA), both of which are postulated to act as potential hypocholesterolemic agents. Procedures have been devised to follow radioactivity incorporation of these precursors into the squalene, lanosterol and cholesterol fractions. The results show that cholesterol synthesis from labeled acetate is noticeably inhibited by BBA final concentrations as small as 10 μM, while the rate of labeling is much less inhibited by HBBA. When acetate is replaced by labeled mevalonate, cholesterol synthesis is hardly inhibited by both BBA and HBBA. The results indicate that BBA probably affects some of the reactions which lead acetate to mevalonate formation. Acetyl‐CoA: ligase (E.C.6.2.1.1) and acetyl‐CoA acetyl transferase (E.C.2.3.1.) therefore have been examined. Ligase activity is substantially inhibited only by 1 mM concentration of BBA and HBBA, whereas the transferase enzyme is unaffected. BBA probably affects other reactions in the metabolic sequence which converts acetate into mevalonate.
γ‐Linolenic acid inAcer seed oils
Authors: Bohannon M. B. , Kleiman R.
Published: November 2006

The octadecatrienoic acids inAcer negundo L. (maple family) seed oil include both 9,12,15‐ (1%) and 6.9,12‐(7%) isomers. The chief monoenoic acids identified were 9‐octadecenoic (21%), 11‐eicosenoic (7%), 13‐docosenoic (15%), and 15‐tetracosenoic (7%). Also present is a considerable amount of 9,12‐octadecadienoic acid. Investigation of ten other Aceraceae revealed their seed oils to have a similar fatty acid composition.
Rate of restoration of cardiolipin and other major phospholipids during liver regeneration in rat
Authors: Fex Göran , Thorzell Kerstin
Published: November 2006

The rate of restoration of liver phospholipids, especially cardiolipin, during liver regeneration after two‐thirds partial hepatectomy, was studied. Preoperative content of cardiolipin was not restored during the first week of regeneration, while this was the case for the other major liver phospholipids. The observations are discussed in relation to the morphogenesis of mitochondria during liver regeneration.
Effect of dietary safflower oil upon lipogenesis in neonatal lamb
Authors: Vernon Richard G.
Published: November 2006

The effect of dietary safflower oil upon lipogenesis has been investigated in neonatal lambs. Preliminary experiments with lambs suckled by their mothers showed that there was a 10‐fold increase in the rate of incorporation of [14C] from acetate into fatty acids in adipose tissue slices during the first 10 days post partum. Barely detectable rates of [14C] acetate incorporation into fatty acids were found in liver slices from lambs during the same period. In lambs given cows' milk from birth until 11 days of age, there was also a 10‐fold increase in the rate of lipogenesis in adipose tissue slices. Supplementing the diet of cows' milk with safflower oil (5 ml/lamb/day) resulted in significantly lower rates of lipogenesis in adipose tissue slices from 11 day old lambs. Administration of safflower oil had no effect upon the concentration of unesterified fatty acids, including linoleic acid, in the lamb adipose tissue slices. The data show that lipogenesis in ovine adipose tissue, like that in rodent liver and adipose tissue, is sensitive to dietary polyunsaturated fatty acids, and that, for the neonatal lamb, the effect of polyunsaturated fatty acids upon lipogenesis is not dependent upon an increase in the tissue concentration of polyunsaturated fatty acids.
Fatty acid and aldehyde composition of major phospholipids in salt gland of marine birds and spiny dogfish
Authors: Bergh C. ‐H. , Larson G. , Samuelsson B. E.
Published: November 2006

The lipophilic components of choline phosphoglycerides and ethanolamine phosphoglycerides obtained from the salt gland of herring gull and eider duck and from the rectal gland of spiny dogfish were investigated by means of thin‐layer chromatography, gas chromatography, and gas chromatography‐mass spectrometry. All phospholipids analyzed were shown to contain small amounts of plasmalogens, and mainly C16, C18, and C18∶1 aldehyde was detected. The fatty acids were composed of saturated, unsaturated, straight chain, and branched chain types, ranging between 14–22 carbon atoms. The lipophilic composition of the rectal gland phospholipids showed a higher degree of unsaturation and the presence of more branched chain fatty acids than that of the birds, possibly related to body temperature.
Composition of liver lipids of the rat during pregnancy and lactation
Authors: Smith R. W. , Walsh A.
Published: November 2006

Triglyceride concentrations in rat liver rose during late pregnancy, declined at peak lactation, and then rose again during involution. The percentage of oleate in the triglycerides rose at peak lactation, but that of linoleate fell. Although phospholipid concentrations were unchanged, the percentage of palmitate in this fraction rose, and those of stearate and arachidonate fell during pregnancy and lactation. These changes may be related to the changes in lipogenesis and fat mobilization that occur during pregnancy and lactation.
Comparison of phospholipid composition ofAedes aegypti andAedes albopictus cells obtained from logarithmic and stationary phases of growth
Authors: Jenkin H. M. , McMeans E. , Anderson L. E. , Yang T. ‐K.
Published: November 2006

Aedes aegypti andAedes albopictus cells were grown in tissue culture and harvested at logarithmic and stationary phases of development. The phospholipids were extracted, separated into lipid classes, and fatty acid composition of each fraction determined. The phosphatidylethanolamine fraction was the major lipid (42–54%). With aging, theA. aegypti cells showed an increase in polyenes in the phosphatidylcholine and phosphatidylethanolamine fractions and in monoenes and polyenes in the phosphatidylinositol fraction. The lysophosphatidylcholine fraction had an increase in chain length of the fatty acids with aging of theA. aegypti cells. TheA. albopictus cells, with aging, showed increases in chain length and in the relative percentage of polyenes in the lysophosphatidylcholine, phosphatidylcholine, and phosphatidylserine fractions. In the phosphatidylinositol fraction, chain elongation of fatty acids occurred as the cells aged. In the ceramide phosphorylcholine fraction, there were increases in saturation and chain elongation of the fatty acids from the logarithmic to the stationary phase of theA. albopictus cells. An increase in polyenes was observed with aging of the cells in the phosphatidylethanolamine fraction.
Furanoid fatty acids from fish lipids
Authors: Glass Robert L. , Krick Thomas P. , Sand Donald M. , Rahn Curtis H. , Schlenk Hermann
Published: November 2006

Fatty acids, recently reported as constitutents of certain fish lipids, were identified to be derivatives of furan (furanoid fish fatty acids). 12,15‐Epoxy‐13,14‐dimethyleicosa‐12,14‐dienoic acid is predominant among the furan acids and is associated withbis‐homologs in regard to chain length. Monomethyl acids, such as 12,15‐epoxy‐13‐methyleicosa‐12,14‐dienoic, are present in appreciable amounts. The structures were concluded from oxidative degradations, from mass spectrometry of methyl esters of the novel acids and fatty acids derived from them by opening the ring, and from nuclear magnetic resonance, infrared, and Raman spectra. The results from chemical procedures and from spectrometric methods were in aggreement with those obtained with authentic methyl 9,12‐epoxyoctadeca‐9,11‐dienoate. The number of substituents at the furan ring greatly influences hydrogenation, hydrogenolysis, and hydrolysis reactions of the ring.