Showing papers in "Journal of the American Oil Chemists' Society in 1963"
TL;DR: Two new schemes for fractionation of complex lipid mixtures are presented and the types of lipid-nonlipid interactions disclosed by column chromatography and their potential application to biological problems are discussed.
Abstract: Two new schemes for fractionation of complex lipid mixtures are presented. Their use for the study of lipids of beef brain, beef liver, and the sea anemone are described. Apparatus and techniques for working in an inert atmosphere, evaporation of solutions in the cold under nitrogen, use of infrared spectroscopy for examination of lipids and their hydrolysis products, preparation and clution of diethylaminoethyl (DEAE) cellulose and silicic acid-silicate columns and general column combinations that can be used to fractionate complex lipid mixtures are considered in detail. The first scheme, employing DEAE cellulose columns followed by thin layer and paper chromatographic examination of the fractions, was applied to liver lipids. The many components, some of them new lipids not previously detected, are clearly seen with this technique but are not seen when paper or thin layer chromatography alone or silicic acid chromatography are used.
593 citations
TL;DR: All configurational features of the lipids in myelin fit these basic models, and it is demonstrated that the cohesional forces at play should indeed promote stable complexes of this kind.
Abstract: Considerable uncertainty still exists regarding the detailed arrangement in protein-lipid molecular associations found in serum lipoproteins, plasma-membranes of cell organelles, the myelin sheath of nerve, and many other structures of paramount importance to biological mechanisms both in health and disease. Working hypotheses concerning such structures must eventually be tested by comparing known properties with those suggested by exact stereomodels. In this type of study, orthogonal projections of the molecules offer several advantages over the tri-dimensional stereomodels from which they can be derived by a described photographic process. The rules governing the configuration to be given the molecular models used for this purpose are discussed, and the possible applications of the resulting diagrams are described and illustrated by numerous examples taken in the lipid field.
255 citations
TL;DR: A chromatographic adsorbent for the separation of geometric isomers of fatty acid methyl esters was developed in this article, which consists of silicic acid impregnated with silver nitrate.
Abstract: A chromatographic adsorbent has been developed for the separation of geometric isomers of fatty acid methyl esters. The adsorbent consists of silicic acid impregnated with silver nitrate.
201 citations
TL;DR: In this paper, a procedure involving thin layer chromatography on silica impregnated with silver nitrate is described, which makes possible the separation of synthetic and natural glyceride mixtures into classes according to their degree of unsaturation, and within those classes the resolution of certain isomeric unsaturated glycerides.
Abstract: The paper describes a procedure involving thin layer chromatography on silica impregnated with silver nitrate, which makes possible the separation of synthetic and natural glyceride mixtures into classes according to their degree of unsaturation, and within those classes the resolution of certain isomeric unsaturated glycerides. The separations depend upon the ability of compounds having an olefinic double bond to form co-ordination complexes with the silver ion.
175 citations
TL;DR: In this paper, a linear relation between retention time on polyester substrates and the number of carbon atoms in the chain of unsaturated fatty acid esters is presented. But this correlation is independent of any relation to the retention times of the esters of the saturated fatty acids, and depends solely on the fatty acid chain length, the number number of double bonds, and the length of the end carbon chain.
Abstract: The correlation of structures of esters of certain unsaturated fatty acids is possible through a linear relation when logarithms of retention time on polyester substrates are plotted against the number of carbon atoms in the fatty acid chain. This correlation is independent of any relation to the retention times of the esters of the saturated fatty acids, and depends solely on the fatty acid chain length, the number of double bonds, and the length of the end carbon chain. It appears to depend on the influence of the latter on vapor pressure. A sound basis is thus provided for advocating a modified equivalent chain length system, virtually independent of temperature effects, and based on certain commonly occurring monounsaturated acids rather than on the saturated acids.
147 citations
TL;DR: Some of the known principles of gas-liquid chromatography are reviewed in this article, where application of the equivalent chain length (ECL) method to identification of complex molecules, and to prediction of structures of unknowns, is described in detail.
Abstract: Some of the known principles of gas-liquid chromatography are reviewed. Application of the equivalent chain length (ECL) method to identification of complex molecules, and to prediction of structures of unknowns, is described in detail.
113 citations
TL;DR: In this article, structural analysis of lecithins and triglycerides is performed by a combination of reductive ozonolysis and thin-layer chromatography (TLC).
Abstract: The structural analysis of lecithins and triglycerides is described. The procedure is carried out on 2–5 mg of sample by a combination of reductive ozonolysis and thin-layer chromatography (TLC). The ozonides as well as the aldehyde “cores” derived from reduction of the ozonides are separated by TLC and analyzed quantitatively by densitometry. The constituent saturated fatty acids of the separated aldehyde “cores” are methylated and analyzed by gasliquid chromatography (GLC). The scope of the method is demonstrated by the analysis of several synthetic and natural triglycerides and several lecithins isolated from natural sources.
100 citations
98 citations
TL;DR: In this article, hot concentrated hyrochloric acid on Florisil was found to be a useful adsorbent for separation of phospholipids and other complex lipids by column chromatography.
Abstract: Acid-treated Florisil, prepared by the action of hot concentrated hyrochloric acid on Florisil, was found to be a useful adsorbent for separation of phospholipids and other complex lipids by column chromatography. This material gave separations similar to those obtained with commercial silicic acid but its coarse mesh size simplified the technical operations and permitted faster flow rates. Its use is illustrated by separations of model compounds and of lipids extracted from liver and brain.
92 citations
TL;DR: In this paper, a rapid titration method was described for the quantitative determination of both cyclopropenoid and epoxy fatty acid derivatives in mixtures, and it was found that epoxy compounds can be titrated selectively with Durbetaki reagent at 3C without interference from cycloprotonoid derivatives.
Abstract: A rapid titration method is described for the quantitative determination of both cyclopropenoid and epoxy fatty acid derivatives in mixtures. It was found that epoxy compounds can be titrated selectively with Durbetaki reagent at 3C without interference from cyclopropenoid derivatives. Cyclopropenoid derivatives can be titrated much more rapidly to a much sharper end point a 55C that at room temperature. Thus mixtures can be analyzed by first titrating at 3C to determine the epoxy compounds and then continuing the titration at 55C to determine the cyclopropenoid components.
91 citations
TL;DR: In this article, a broad-band NMR spectrometer was used to examine 12 seed oils containing a variety of functional groups and the instrument response was directly related to hydrogen content of the seed oil regardless of the structures present.
Abstract: Twelve seed oils containing a variety of functional groups were examined with a commercial broad-band nuclear magnetic resonance (NMR) spectrometer. Instrument response (integrator readout) was directly related to hydrogen content of the oil (r=0.999), regardless of the structures present.
TL;DR: In this paper, the linoleic and linolenic acids at different dietary levels, at different temperatures, with and without other dietary fat were presented with different levels of fat.
Abstract: Marine and fresh water fish were depleted of tissue unsaturated fatty acids to various degrees and subsequently presented with linoleic and linolenic acids at different dietary levels, at different temperatures, with and without other dietary fat.
TL;DR: Thin-layer chromatography systems are described for separation of most tissue phospholipid and sphingolipids and acidic lipids such as phosphatidyl serine and cerebroside sulfate are resolved without streaking on several types of modified silica gel.
Abstract: Thin-layer chromatography systems are described for separation of most tissue phospholipids and sphingolipids. Acidic lipids such as phosphatidyl serine and cerebroside sulfate are resolved without streaking on several types of modified silica gel.
TL;DR: Even chain sodium alkanesulfonates from the Strecker reaction, odd chain sodium 1-hydroxy-2-alkane-sulfonic acids from the alkaline decarboxylation of α-Sulfo acids, and sodium 1, hydroxyl 2-alkanesulfonic acid from the reduction of esters of α -sulfo acid were compared with respect to Krafft point, critical micelle concentration, detergency and foam height as mentioned in this paper.
Abstract: Even chain sodium alkanesulfonates from the Strecker reaction, odd chain sodium alkanesulfonates from the alkaline decarboxylation of α-sulfo acids, and sodium 1-hydroxy-2-alkanesulfonates from the reduction of esters of α-sulfo acids were compared with respect to Krafft point, critical micelle concentration, detergency and foam height. Sodium alkanesulfonates and crude fusion products from the α-sulfo acids (mixtures of alkanesulfonates of one less carbon atom with a lesser amount of a soap of two less carbon atoms) are more soluble and have better detergent and foaming properties. Sodium 1-hydroxy-2-alkanesulfonates resemble monosodium salts of α-sulfo acids. Alkanesulfonic acids and 1-hydroxy-2-alkane-sulfonic acids obtained from the sodium salts by ion exchange have lower Krafft points and are more readily soluble. The critical micelle concentrations of 1-hydroxy-2-alkanesulfonic acids and α-sulfo acids are nearly the same and about equal to those of alkanesulfonic acids of one less carbon atom.
TL;DR: In this paper, the area response obtained in the hydrogen flame ionization detector has been used to calculate the molar proportions for the various triglyceride types in a blended butterfat sample: C24 0.57, C27 0.18, C28 0.81, C29 0.17, C30 1.15, C31 0.5, C33 0.34, C34 5.41, C35 1.0, C36 10.6
Abstract: Gas liquid chromatographic triglyceride separation by carbon number, and integration of the area response obtained in the hydrogen flame ionization detector, has permitted the calculation of the following molar proportions for the various triglyceride types in a blended butterfat sample: C24 0.5, C25 0.08, C26 0.57, C27 0.18, C28 0.81, C29 0.17, C30 1.15, C31 0.2, C32 3.1, C33 0.34, C34 5.41, C35 1.0, C36 10.6, C37 1.2, C38 12.8, C39 1.15, C40 10.7, C41 1.0, C42 6.1, C43 0.58, C44 5.15, C45 0.6, C46 5.8, C47 1.0, C48 6.45, C49 1.47, C50 8.5, C51 1.43, C52 6.95, C53 1.05, C54 4.0. The validity of these estimates was verified by similar determinations performed on molecular distillates of butterfat and on butterfats with known amounts of added saturated and unsaturated long chain triglycerides. The fatty acid carbon recoveries estimated on the basis of the observed triglyceride peak proportions were of the order of 95% or better.A comparison of the experimentally determined triglyceride type distributions with those calculated on the basis of a completely random fatty acid arrangement for the blended and the molecularly distilled samples showed considerable differences, the most apparent of which was the greater proportion of both short and long chain triglycerides consistently predicted for the random population. On the basis of these studies, it is suggested that butterfat possesses a non-random fatty acid distribution which is reflected in its triglyceride type distribution.
TL;DR: The use of gas-liquid chromatography (GLC) separation factors between methyl esters of unsaturated fatty acids is feasible as a means of tentative identification, either between acids of one chain length and differing numbers of double bonds as mentioned in this paper.
Abstract: The employment of gas-liquid chromatography (GLC) separation factors between methyl esters of unsaturated fatty acids is feasible as a means of tentative identification, either between acids of one chain length and differing numbers of double bonds, or between acids of one chain length and the same number of double bonds in differing positions, provided the acid structures are appropriately grouped by end carbon chain. The modification of separation factors by temperature, chain length, number of double bonds, or position of double bonds is apparent from examination of a larger number of examples than was hitherto available. Examples of the usefulness of separation factors in identifying unknowns or predicting retention times are given.
TL;DR: In this article, a base-catalyzed alcoholysis of fish-oil triglycerides with alcohols of low molecular weight has been applied to the preparation of alkyl esters using high molecular weight, aromatic, and terminally unsaturated alcohols.
Abstract: A previously described procedure for the basecatalyzed alcoholysis of fish-oil triglycerides with alcohols of low molecular weight has been applied to the preparation of alkyl esters using high molecular weight, aromatic, and terminally unsaturated alcohols. Some monoethers of ethylene-and diethylene glycol have also been used in this work. Thin-layer chromatography was used to follow the course of the reaction and determine optimum reaction times and yields of products.
TL;DR: A variety of hydrogen peroxide-derived systems for amine oxidation were investigated in this paper, and the results of an investigation leading to the selection of optimum conditions for producing these compounds are reported.
Abstract: Oxides of tertiary amines, such as dimethyldodecylamine oxide, are known to be useful as detergents and foam stabilizers, and are now in commerical use. The results of an investigation leading to the selection of optimum conditions for producing these compounds are reported. A variety of hydrogen peroxide-derived systems for amine oxidation were investigated. These included hydrogen peroxide in water and in nonaqueous solvents, and peroxy acids under various reaction conditions. Reductometric, acidimetric, and gas chromatographic procedures were used for analysis of reaction mixtures. The preferred reaction uses hydrogen peroxide as oxidant and water as the reaction medium. The product of this reaction is a 30–40% solution of the amine oxide. Other factors affecting the rate and extent of conversion, such as amine purity, are discussed.
TL;DR: A comprehensive review of literature on petroselinic acid and its derivatives can be found in this paper, where various methods of chemical modification have been investigated and the derivatives obtained have been summarized in tabular form.
Abstract: This publication contains a comprehensive review of literature on petroselinic acid and its derivatives All known sources of petroselinic acid including its synthetic derivation have been explored and described The different plant species, whose seeds offer an oil reported to contain petroselinic acid, have been listed and the amounts of oil and their prevalent fatty acid components given Its method of isolation from the naturally occurring triglycerides and identification have been discussed The descriptions of characteristics and properties of petroselinic acid and its various derivatives are also included In many cases they have been compared to oleic acid and other related fatty acids and their derivatives The various methods of chemical modification of petroselinic acid have been, investigated and the derivatives obtained have been summarized in tabular form Some potential uses for petroselinic acid and the products obtained from it have also been discussed This review was designed to show that is known about petroselinic acid to date, and perhaps to create further interest in research on this unique naturally occurring octadecenoic acid
TL;DR: The geometric isomers of many unsaturated fatty acid methyl esters can be separated using high-resolution gas-liquid chromatography on polyester or Apiezon columns as discussed by the authors.
Abstract: The geometric isomers of many unsaturated fatty acid methyl esters can be separated using high-resolution gas-liquid chromatography on polyester or Apiezon columns. Separations reported for the geometric isomers of monounsaturated, ricinoleic, linoleic, conjugated, and epoxy fatty acids are reviewed here. New data is presented on the resolution of linolenate geometric isomers on both polyester and Apiezon columns. The separation of methyl oleate and methyl elaidate on a polyester column has also been accomplished. Techniques for preparing and using the high-resolution columns necessary for these separations are reviewed.
TL;DR: In this article, the equilibrium composition of cis and trans isomers obtained by isomerizing oleic, linoleic, and linolenic acids with selenium or nitrous acid has been studied using gas chromatography and infrared spectroscopy.
Abstract: The equilibrium composition ofcis andtrans isomers obtained by isomerizing oleic, linoleic, and linolenic acids with selenium or nitrous acid has been studied using gas chromatography and infrared spectroscopy. The oleic/elaidic equilibrium mixture was found to contain 75–80% elaidic acid instead of the generally accepted 66% value. It is felt that the greater accuracy of gas chromatography and infrared analyses over older methods allows this equilibrium to be defined with greater precision. Similar studies on thecis-trans isomerization of linoleic and linolenic acids indicated that their equilibrium mixtures also contained 75–80%trans double bonds. With linoleic acid, thesetrans bonds were shown to be randomly distributed among the double bonds present. Cis-trans isomerization of linoleic or linolenic acids with selenium produced by-products having elution times equivalent to 18∶2, 18∶1, and 18∶0 on a gas chromatograph. No such by-products were observed when oleic acid was isomerized. Apparently some type of hydrogen-transfer reaction accompanies thecis-trans isomerization of polyunsaturated acids with selenium.
TL;DR: In this article, a number of chemical and physical techniques have been used for the analysis of polymerized oils, including determinations of acetone number, iodine value (I.V.), molecular weight, dielectric constant, viscosity, and refractive index.
Abstract: Fats and fatty acids are polymerized by oxidative or thermal processes. Structures have been deduced by using a number of chemical and physical techniques. General methods applicable to the analysis of polymerized oils include determinations of acetone number, iodine value (I.V.), molecular weight, dielectric constant, viscosity, and refractive index. Monomers, dimers, and trimers are separated generally by molecular distillation. In addition, urea fractionation and a number of chromatographic techniques are useful for the detection of monomers, dimers, and polymers.
TL;DR: In this paper, an intraperitoneal injection of methyl linolenate-1-C14 into kelp bass, Paralablax clathratus, the highly polyunsaturated fatty acids of their body fats were concentrated by low temperature crystallization from acetone, and eicosapentaenoic and docosahexaenoic acids were isolated from the concentrate by reversed-phase chromatography and hydrogenated.
Abstract: Following intraperitoneal injection of methyl linolenate-1-C14 into kelp bass,Paralablax clathratus, the highly polyunsaturated fatty acids of their body fats were concentrated by low temperature crystallization from acetone, and eicosapentaenoic and docosahexaenoic acids were isolated from the concentrate by reversed-phase chromatography and hydrogenated. The resulting arachidic and behenic acids were degraded stepwise to margaric acid, and the distribution of activity was determined. The results indicate that the injected linolenic acid was converted to eicosapentaenoic acid and the latter incorporated into docosahexaenoic acid. A probable conversion pathway is linolenic acid→6,9,12,15-octadecatetraenoic acid→8,11,14,17-eicosatetraenoic acid→5,8,11,14,17-eicosapentaenoic acid→7,10,13,16,-19-docosapentaenoic acid→4,7,10,13,16,19-docosahexaenoic acid.
TL;DR: In this article, the application of reversed-phase, liquid-liquid partition chromatography to the preparation of highly purified methyl esters of fatty acids is described, and the parameters of fractionation of methyl ester by this method are demonstrated with model mixtures of these compounds.
Abstract: The application of reversed-phase, liquid-liquid partition chromatography to the preparation of highly purified methyl esters of fatty acids is described. The parameters of fractionation of methyl esters by this method are demonstrated with model mixtures of these compounds. Model mixtures are also used to demonstrate the use of adsorption chromatography on columns of silicic acid, impregnated with silver nitrate, in conjunction with liquid-liquid partition chromatography to eliminate fractional distillation in the preparation of polyunsaturated methyl esters. The formation of artefacts of 4, 5 and 6 double bond methyl esters during fractional distillation and their fractionation is described. The use of liquid-liquid partition chromatography for preparative purposes on a large laboratory scale is demonstrated by the preparation of pure methyl linolenate from linseed oil esters. Methyl arachidonate, eicosapentaenoate, docosapentaenoate and docosahexaenoate are also prepared in high purity.
TL;DR: Complexes were formed between egg albumin and oxidized lipids, such as thermally oxidized corn oil and autoxidized linoleic acid, under a standardized set of conditions.
Abstract: Complexes were formed between egg albumin and oxidized lipids, such as thermally oxidized corn oil and autoxidized linoleic acid, under a standardized set of conditions. No complex could be obtained under these conditions when lysine, glycine, bactopeptone, gelatin or sodium caseinate were substituted for egg albumin. Lactalbumin was equally as reactive, casein much less and fresh egg white superior to egg albumin in their complexing ability with oxidized corn oil. As the time of reaction was increased, the amount of the complex formed also increased. Optimum complex formation took place at a concentration of 1% protein, a pH of 7 and 60C. The ease of formation of these complexesin vitro indicated that similar complexing could readily take placein vivo under suitable pathological conditions.
TL;DR: In this article, the lipids extracted from four locations on a hog carcass were fractionated into non-phospholipids, phosphatidyl ethanolamine, and sphingomyelins.
Abstract: The lipids extracted from four locations on a hog carcass were fractionated into nonphospholipids, phosphatidyl ethanolamine, phosphatidyl serine, lecithins, and sphingomyelins. The identities of phospholipid fractions were established and their quantitative contents were determined by three methods: gravimetrically, from analysis of the phosphorus content, and from standard curves of infrared spectra. Variations in content of a phospholipid type were noted in the carcass locations studied. Lecithin and phosphatidyl ethanolamine were found in greatest quantity. These represented ca. 61% and 31%, respectively, of the total phospholipids. The remainder was distributed between phosphatidyl serine and sphingomyelin at 5% and 3%, respectively. The phospholipid content of hog meat was found to be slightly over 0.5%.
TL;DR: In this article, the tentative identification of unsaturated C16 acids of marine oils is facilitated through analysis on both normal and organosilicone polyester substrates, and two different separation factors can then be approximated from the more accessible separation factors appropriate to unsaturated acids of longer chain lengths.
Abstract: The tentative identification of the unsaturated C16 acids of marine oils is facilitated through analysis on both normal and organosilicone polyester substrates. Two different separation factors can then be approximated from the more accessible separation factors appropriate to unsaturated acids of longer chain lengths.
TL;DR: In this paper, a gravimetric method for studying the factors involved in removing fatty soils from cotton in aqueous detergent systems is described, and comparative data are given for removal of lanolin, lard, sebum, and hydrocarbon soil from cotton.
Abstract: A gravimetric method for studying the factors involved in removing fatty soils from cotton in aqueous detergent systems is described, and comparative data are given for removal of lanolin, lard, sebum, and hydrocarbon soils from cotton. Comparisons are made for a number of surfactants used in detergent formulations and effects of various builders are noted. Effects of some of the parameters of the wash bath such as detergent concentration, water temperature, and wash time are discussed. It is thereby demonstrated that:
1.
Maximum fatty soil removal is attained from cotton in 5 min or less at 120F with 0.25% of a good detergent.
2.
A group of six representative anionic and nonionic surfactants vary considerably in their ability to remove sebum from cotton.
3.
In general, the relative ability of a detergent system to remove one fatty soil applies to other fatty soils also.
4.
The most effective inorganic salts for removing sebum were sodium tripolyphosphate and tetrasodium pyrophosphate.
5.
The most effective active-builder combinations tested were built with sodium tripolyphosphate.
6.
The improvement in fatty soil removal from cotton produced by building surfactants with inorganic salts was an additive or less than additive affect for the nonionics tested. With the anionies a few synergistic effects were noted. These effects were probably due to the inorganic salts lowering the CMC or increasing the size of the micelle.
7.
Emulsification is probably an important mechanism in removing sebum from cotton.
TL;DR: In this paper, a simple method of obtaining reproducible cooling curves has been developed for determining melting point and transformation time of the unstablea-form, which has a marked influence on the consistency of commercial fats.
Abstract: A simple method of obtaining reproducible cooling curves has been developed. A microscopical technique is described for determining melting point and transformation time of the unstablea-form, which has a marked influence on the consistency of commercial fats.
TL;DR: The structural analysis of micro quantities of alkyl aryl sulfonates by presently known chemical and spectroscopic techniques has been an exceedingly difficult task as discussed by the authors, due largely to the essential nonvolatility of the sulfonate, a fact which precludes the application of gas-liquid chromatography and mass spectrometric techniques.
Abstract: The structural analysis of micro quantities of alkyl aryl sulfonates by presently known chemical and spectroscopic techniques has been an exceedingly difficult task. The formidable nature of such analyses is due largely to the essential nonvolatility of the sulfonates, a fact which precludes the application of gas-liquid chromatography and mass spectrometric techniques.