Studies on Mirabilis jalapa (Four O'clock Plant) Seed Oil

Mirabilis jalapa of Nyctaginaceae plant family yields 4–5% of fatty oil. The oil is investigated for its glycerides and fatty acid composition by gas liquid chromatography. The fatty acids in the seed oil constitute C_16:0, 18.3%;C_18:1,55.3%;C_18:2,11.5%;C_18:3,14.9%. The triglyceride components were also determined by separating the triglycerides according to their degree of unsaturation by means of thin-layer chromatography on silica gel impregnated with silver nitrate. The fatty acid composition of the different triglyceride fractions was determined. Moreover, the triglycerides were separated according to their carbon number by gas liquid chromatography.     

Über die Zusammensetzung der Braunkohle XIII Aliphatische Ketone des tschechischen Rohmontanwachses

Composition of Lignite XIII: Aliphatic Ketones in Czecho-Slovakian Crude Montana Wax A fraction of aliphatic ketones could be isolated from the resinous portion of Czecho-Slovakian crude montana wax by repeated column chromatography. Two homologous series of ketones were detected in the aforesaid fraction with the aid of IR-spectroscopy, thin-layer chromatography, gas chromatography and mass spectrometry. One homologous series consisted of unbranched aliphatic methyl ketones (C₁₂-C₃₉) containing predominantly odd-number components. The other homologous series contained unbranched ketones (C₂₅-C₃₅) in which the keto-groups were located at the middle of the carbon chain or in the vicinity of the central carbon.     

Reactions of dimethyl sulfoxide with sulfonate esters of fatty alcohols. I. Synthesis of higher saturated and unsaturated fatty aldehydes

Long-chain saturated fatty aldehydes (C₁₀ to C₁₈), as well as the C₁₈ unsaturated aldehydes (oleyl, linoleyl, and linolenyl), were synthesized in good yields by the selective oxidation of the sulfonate esters of the corresponding alcohols with dimethyl sulfoxide in the presence of sodium bicarbonate. Chromatographic procedures for the isolation of the pure aldehydes from the reaction mixtures are described. The purity of the aldehydes was ascertained by thin-layer chromatography, melting points of their 2,4-dinitrophenyl hydrazones, infrared spectra and other physical methods. Presented at the AOCS Meeting in Houston, April, 1965.     

Lipase-catalyzed monoesterification of 1-O-hexadecylglycerol in organic solvents

A simple method is presented to esterify 1-O-hexadecyl-rac-glycerol using lipases in different organic solvents. The following fatty acids were used: C_14∶0, C_16∶0, C_18∶0, C_18∶1, and C_18∶2. Monoesterification was achieved by using a limiting amount of the fatty acid. Both the 1-O-hexadecyl-3-O-acylglycerol and the 2-O-acylglycerol were obtained in a total yield of 75% and a ratio of 7∶1 in dichloromethane after 3 d. Chromatographic data for the monoesters, useful for the identification of the natural products, are given (gas-liquid chromatography, thin-layer chromatography, reverse-phase thin-layer chromatography). The structure was confirmed by a chemical synthesis of 1-O-hexadecyl-2-O-hexadecanoylglycerol. The 3-O-glyceride was also formed by acyl migration, as the minor component. The monoesters were separated by column chromatography and characterized by ¹H and ¹³C nuclear magnetic resonance spectra.     

Hydrierung von Lipiden als Hilfsmittel zur Identifizierung und Quantifizierung von Phosphatiden aus Membransystemen des Herzmuskels

Hydrogenation of Lipids for Identification and Quantification of Phosphatides from Pellicle Systems of Cardiac Muscle. It was the aim of our research to show that hydrogenation of lipids is an auxiliary technique in phospholipid analysis of cardiac membranes. This is of interest if a preliminary overview on lipid fractions containing highly unsaturated fatty acids is needed. The fatty acids and the diglycerides from phospholipids were hydrogenated according to the procedure described by Appelqvist (A simple and convenient procedure for the hydrogenation of lipids on the micro- and nanomole scale, J. Lipid Res. 13 (1972), 146) with platinum oxide as a catalyst. The lipids (fatty acid methyl esters or acetylated diglycerides) were taken to dryness in a test-tube under nitrogen and flushed with hydrogen. The catalyst, suspended in methanol was injected through a septum. For identification purposes thin-layer chromatography on silica gel and on silica gel impregnated with silver nitrate was combined with gas chromatography before and after hydrogenation. After hydrogenation the fatty acid profile is much simpler and the fatty acid methyl esters can easily be differentiated from dimethyl acetals, as the latter are more volatile. Diacylglycerides and alkenylacylglycerides were also separated by thin-layer chromatography in individual subclasses before they were analysed by gaschromatography. Hydrogenating the lipids makes it possible to circumvent in part difficulties which arise often with polyunsaturated fatty acids. As the chain length of C20 and C22 are mainly represented by C20:4 , the arachidonic acid and C22:6 the docosahexaenoic acid, both fatty acids can be assessed after hydrogenation. The fatty acid profile of phosphatidylcholine and phophatidylethanolamine of cardiac muscle from rat, guinea pig and pig was determined. Each sample was analysed before and after hydrogenation. The fatty acids with the same chain length were summed up and compared to the corresponding chain length after hydrogenation.     

An improved reversed-phase thin-layer chromatography method for separation of fatty acid methyl esters

Resolution of fatty acid methyl esters (FAME) by thin-layer chromatography often is complicated by co-migration of certain acyl-isomers in heterogeneous mixtures. However, a novel reversed-phase thin-layer chromatography method which employs 10% (wt/vol) silver nitrate in a mobile phase containing acetonitrile/1,4-dioxane/acetic acid (80:20:1, vol/vol/vol) allows one-dimensional resolution of a wide range of acyl-methyl esters. This innovation enables improved separation of saturated FAME ranging from C₁₂ to C₂₂, and geometric isomers of C₁₄ to C₂₂ unsaturated FAME by thin-layer chromatography.     

Identifizierung von molekularen Phospholipid-Species aus Schweineherz durch Kombination chromatographischer Techniken

Identification of Molecular Species of Phospholipids from Pig Heart by Combining Chromatographic Techniques. Glycero-phospholipids from subcellular organelles and membranes from pig heart were divided into subclasses. The molecular species within the main subclasses were analyzed. The phosphorus moiety had been removed by phospholipase-C and the acetylated molecules were separated in diacyl-, alkylacyl- and alkenylacyl-glycerols by thin-layer chromatography (TLC). For further identification the subclasses from the first fractionation by TLC were separated by silver ion chromatography according to their polarity. A small portion of the acetylated diradyl-species was transesterified so that the fatty acid composition could be assessed as methyl esters. The acetylated molecular species derived from glycerophospholipids were chromatographed on WCOT fused silica columns with TAP as stationary phase according to molecular weight and unsaturation. Gaschromatography (GC) of fatty acid methyl esters and dimethylacetals from plasmalogens was executed on DEGS-columns or on WCOT fused silica columns with CP-Sil 88 as stationary phase. The distribution of molecular species within a phospholipid class (PC or PE) was rather similar for the diacyl-and the alkenylacyl molecules. But the latter are more volatile. In the case of phosphati-dylcholine the composition of C₁₆-C_18-:1; C₁₆-C_18:2 and C₁₈-C_18:2 was predominant for diacyl- as well as alkenylacyl-species. In the case of phosphatidylethanolamine the fatty acid composition of C₁₈-C_20:4 and C₁₈-C_18:2 were the most important species. The composition of fatty acids in diacyl-and alkenylacyl-species is of special interest as the metabolism of diacyl-glycerophospholipids is quite different from alkenylacyl-glycerophospholipids.     

Molecular species of glycerophospholipids and sphingomyelins of human erythrocytes: Improved method of analysis

This study reports the application of modern methods of molecular species analysis in determination of the structure of both major and minor glycerophospholipids and sphingomyelins of human erythrocytes. Individual phospholipid classes were resolved from total lipid extracts by thin-layer chromatography. Diradylglycerols were released by phospholipase C and converted into trimethylsilyl ethers, which were resolved into the alkenylacyl, alkylacyl and diacylglycerol subclasses by normal phase high performance liquid chromatography. Molecular species of diradylglycerols and ceramides were quantitated according to carbon and double bond number by gas liquid chromatography using a fused silica capillary column wall-coated with bonded RTx-2330. The molecular species of ceramides were determined by GC/MS. The diradyl glycerophosphocholines contained 93.0% diacyl, 4.6% alkylacyl and 2.5% alkenylacyl, white the diradyl glycerophosphoethanolamines were made up of 48.8% diacyl, 47.8% alkenylacyl and 3.4% alkylacyl subclasses. Analysis of the molecular species showed that the long chain polyunsaturated acids were mainly combined with C₁₆ in all diradyl GPC subclasses and in diacyl GPE, while in the alkylacyl and alkenylacyl GPE and in diacyl glycerophosphoinositol and diacyl glycerophosphoserine they were combined mainly with C₁₈ saturated fatty chains. In addition to the C₁₆ and C₁₈ alkyl and alkenyl, the ether fractions also contained significant proportions of C₂₀, C₂₂ and C₂₄ chains. The molecular species of the ceramide moieties of the SPH were made up largely of mono- and diunsaturated species. Over 200 molecular species were identified and quantitated in a representative sample of human red blood cells.     

Über die Fettsäurezusammensetzung der Lipoide einiger Gewürze

Fatty Acid Composition of Lipids of Some Spices Fatty acid composition of lipids of ten fruit spices (pepper, pimento, red pepper, chillies, cumin-seed, coriander, celery, dill, cardamon and vanilla), one seed spice (nutmeg), one flower spice (clove), three herb spices (sage, origano, thyme), one leaf spice (laurel), one bark spice (cinnamon) and ginger was determined by gas chromatography after transesterification and compared with the known values. In the lipids of cardamon, vanilla, cinnamon, ginger and laurel, which have not been examined so far, palmitic, oleic and linoleic acids were found to predominate. In the lipids of pimento and clove which belong to the family of myrtaceae, C₁₈ fatty acids were predominant. Spices belonging to the family of labiates are characterized by a high linolenic acid content.     

The effect of lyophilization on the solvent extraction of lipid classes,fatty acids and sterols from the oysterCrassostrea gigas

The lipid class compositions of adult Pacific oysters [Crassostrea gigas (Thunberg)] were examined using latroscan thin-layer chromatography/flame-ionization detection (TLC/FID), and fatty acid compositions determined by capillary gas chromatography and gas chromatography/mass spectrometry (GC/MS). The fatty acid methyl esters were separated using argentation TLC and also analyzed as their 4,4-dimethyloxazoline derivatives using GC/MS. Major esterified fatty acids inC. gigas were 16∶0, 20∶5n−3, and 22∶6n−3. C₂₀ and C₂₂ nonmethylene interrupted (NMI) fatty acids comprised 4.5 to 5.9% of the total fatty acids. The NMI trienoic fatty acid 22∶3(7,13,16) was also identified. Very little difference was found in the proportions of the various lipid classes, fatty acids or sterols between samples of adult oysters of two different sizes. However, significant differences in some of the lipid components were evident according to the method of sample preparation used prior to lipid extraction with solvents. Lyophilization (freeze drying) of samples led to a significant reduction in the amounts of triacylglycerols (TG) extracted by solvents in two separate experiments (7.0 and 52.5% extracted). Extracts from lyophilized samples had less 16∶0, C₁₈ unsaturated fatty acids, and 24-ethylcholest-5-en-3β-ol, while C₂₀ and C₂₂ unsaturated fatty acids comprised a higher proportion of the total fatty acids. There was no significant change in the amounts of polar lipids, total sterols, free fatty acids or hydrocarbons observed in extracts from lyophilized samples relative to extracts from nonlyophilized samples. Addition of water to the freezedried samples prior to lipid extraction greatly improved lipid yields and resulted in most of the TG being extracted.     

Über die Zusammensetzung des Samenöles aus Traubenholunder (Sambucus racemosa L.)

Composition of the Seed Oil of Clustered Elder (Sambucus racemosa L.) The seeds of clustered elder (Sambucus racemosa L.) contain 28% of an oil. Its separation to groups of components was carried out by adsorption chromatography. Single groups of substances were further analysed by TLC and GLC in combination with physico-chemical methods (IR and MS). Thus the following substances were found and identified: n-alkanes (C₁₇–C₃₃), 2-methyl- and 3-methylalkanes, squalene, a mixture of esters, triglycerides, β-sitosterol, campesterol and a mixture of diglycerides. The conditions for the separation of esters by silica gel column chromatography were also found. The mixture of esters was thus separated into a group of aliphatic wax esters (C₃₄–C₄₄) and four groups of esters of steroidal alcohols (mainly β-sitosterol and campesterol) with aliphatic unsaturated acids (predominantly C_18:1, C_18:2 and C_18:3). In the triglycerides representing the main fraction of the oil (93%), the acids C_16:0, C_18:1, C_18:2 and C_18:3 are present. The same acids were also found in diglycerides.     

Essential fatty acid-deficient rats: II. On the fatty acid composition of partially hydrogenated arachis,soybean and herring oils and of normal,refined arachis oil

The fatty acid composition of partially hydrogenated arachis (HAO), partially hydrogenated soybean (HSO) and partially hydrogenated herring (HHO) oils and of a normal, refined arachis oil (AO) was studied in detail by means of direct gas liquid chromatography, ultraviolet and infrared spectrophotometry and by thin layer chromatography fractionation on silver nitrate-silica gel plates followed by gas liquid chromatography. It was shown that the partially hydrogenated oils all contained fatty acids withtrans double bonds. In the plant oils, thetrans acids were present mainly as elaidic acid. The HHO showed an almost equal distribution betweentrans 18∶1 ω9,trans 20∶1 ω>9 andtrans 22∶1 ω>9. Sometrans configuration was also found in the C₂₀-and C₂₂-dienes and trienes of the HHO. In all the oils, conjugated fatty acids were present in minor amounts only (<0.5%). Special attention was given to the ω-acids known to be of specific nutritional value. The HSO contained about 32% linoleic acid, whereas the content ofcis, trans+trans, cis andtrans, trans octadecadienoic isomers was 1.7% and 0.5%, respectively. The amount of linoleic acid in the HSO was even higher than that of AO (29%). The HAO contained only 0.8% 18∶2 ω6 (linoleic acid). Further, two 18∶2 fatty acids with ω>6, acis, cis and atrans, trans isomer, were present in small amounts. The HHO contained 0.5% 18∶2 ω6 (linoleic acid). Isomers of 18∶2 ω>6 were also found in the HHO. They may be hydrogenation products of higher unsaturated C₁₈-acids orginally present. All the C₂₀- and C₂₂-dienes and trienes were shown to have an ω-chain greater than 6. Fatty acids with ω6-structure were not formed during partial hydrogenation of the oils studied.     

Darstellung,Struktur und Reaktivität quartärer Ammoniumcellulosate

Tetraalkylammonium cellulosates were prepared by means of an exchange reaction between cellulose and tetraalkylammonium methoxides in anhydrous methanol and dimethylsulfoxide up to a degree of substitution of about 0,7 without chain degradation. The course of this reaction and the structure of the cellulosates in comparison to lithium and sodium cellulosate has been studied. The reaction rate and the equilibrium substitution decreased with increasing size of the cation in the methoxide. The distribution of the alcoholate groups in equilibrium at C-2, C-3 and C-6 of the glucopyranosyl unit in the cellulosates, which was investigated by methylation, hydrolysis of the methylcelluloses, and analysis of the methylglucoses by gas chromatography, was independent of the nature of the cation. Under the given reaction conditions the hydroxyl group at C-2 was more acidic than those at C-3 and C-6, while for the latter practically no difference was found. The tetraalkylammonium cellulosates are highly reactive intermediates for the preparation of cellulose derivatives. The reactivity of the cellulosates increased with increasing size of the cation, Li^⊕ < Na^⊕ < N(CH₃)₄^⊕ <[(CH₃)₃N? CH₂? C₆H₅]^⊕.     

Die Dünnschicht-Chromatographie in der Wachsanalytik: Die Identifizierung der Wachsalkohole und -säuren

Thin-layer Chromatography in the Wax Analysis: The Identification of Wax Alcohols and Acids A thin-layer chromatographic method employing the following conditions has been developed for the separation of wax alcohols and acids. Adsorbent: Kieselgur G; impregnating solution: 0.5 vol% silicon oil + 10 vol% tetradecane in petroleum ether; stationary phase: tetradecane-silicon oil (Bayer PN 1000); C₁₄ to C₂₄: temperature 42° C; mobile phase: 90 vol% acetic acid, which is completely saturated with pure tetradecane at 42° C; C₂₂ to C₄₀: temperature 60° C; mobile phase: 96 vol% acetic acid, which is completely saturated with pure tetradecane at 60° C; detecting agent: 10% aqueous sodium hydroxide solution mixed with an equal volume of 0.1 molar (1.6%) aqueous potassium permanganate solution.     

Säurekatalysierte Umsetzungen von Aromaten mit Alkanen und Cycloalkanen. X. Alkylierungen mit Cyclohexan

Acid-catalyzed Reactions of Aromatic Hydrocarbons with Alkanes and Cycloalkanes. X. Alkylations with Cyclohexane The complex reaction mixtures of the nonconventional alkylation of benzene with cyclohexane in the presence of Lewis/proton acids and promotors were investigated by gas-liquid chromatography and mass spectrometry. Four representative groups of hydrocarbons were found including cycloalkylbenzenes, substituted indanes or tetralines (C₁₂H₁₆), C₁-C₆-alkylbenzenes and isomeric biscycloalkyls (C₁₂H₂₂). Their formation is interpreted as a competition between alkylation, (without or with isomerization), ringfission with cycloalkylation or fragmentation, and self-alkylation; phenylcycloalkylcations and phenylalkylcations are the intermediates.     

Carbazoles of Surakhan crude oil

• 1.1. A carbazole concentrate was separated from the acid extract of a heavy residue b.p.>350°C of Surakhan crude oil by thin-layer and adsorption chromatography on silica gel.
• 2.2. Carbazole, C₁–C₆-alkylcarbazoles, C₁–C₄-alkylbenzocarbazoles and C₁–C₂-alkylphenylcarbazoles were identified by GC MS in the sample separated.

     

Jahreszeitliche Veränderung des Gehaltes an Kohlenwasserstoffen im Milchfett

Seasonal Variation in Hydrocarbon Content of Milk Fat Saturated and the monounsaturated hydrocarbons were isolated from the unsaponifiable matter of milk fat by means of column chromatography on silicagel impregnated with AgNO₃. Each group was further resolved by gas chromatography. The content of saturated hydrocarbons, predominantly n-alkanes from C₁₄ to C₃₅, amounted to 20–60 ppm., whereas the content of predominantly branched chain monoolefines was between 16 to 80 ppm. The total content as well as the distribution of the hydrocarbons in column- and gas-chromatographic fractions showed characteristic seasonal variation.     

Unsaturated C18 α-hydroxy acids inSalvia nilotica

The oil ofSalvia nilotica Jacq. (Labiatae) seed contains 0.6% α-hydroxyoleic, 4.2% α-hydroxylinoleic, and 5.4% α-hydroxylinolenic acids. The first two have not been found previously in seed oils. In addition to the common fatty acids, also identified were small amounts of three unsaturated C₁₇ acids and one branched chain C₁₇ acid. Methyl esters of the component fatty acids were fractionated by both column and thin-layer chromatography. These esters were identified by combination of gas chromatography, GC-mass spectrometry, ozonolysis-GC, infrared, and nuclear magnetic resonance.     

Separation of milk fat triacylglycerols by argentation thin-layer chromatography

Argentation thin-layer chromatography was investigated as a method of obtaining detailed compositional information about milk fat. A modified argentation thin-layer chromatography procedure, developed to optimize the separation of the complex mixture of total milk fat triacylglycerols, provided nine different groups of triacylglycerols, based on both the degree of unsaturation and the total length of fatty acid groups. Fatty acid methyl ester (FAME) analysis was performed to determine the composition of each band. Separation on the basis of chainlength was most pronounced among the fully saturated triacylglycerol groups, as evidenced by the high level of C_4:0 and C_6:0 in bands 7 and 8, respectively. For the cis-monoenoic triacylglycerols, the separation of C_4:0 and C_6:0 was less distinct. The cis,cis dienes and other dienoic, trienoic, or tetraenoic species were principally observed in two bands of retention factor <0.08 on the chromatography plate. Minimal cross-contamination of bands was observed, with the exception of the lowest of the trisaturate bands, band 7, in which trans-monoenes were found to be present. Three samples from different points of the New Zealand dairy season were separated by argentation thin-layer chromatography, and their FAME distributions were measured. In addition to differences in the masses of band extracts from these samples, levels of C_10:0 and C_12:0 in all bands, and levels of monounsaturates in the dienoic and trienoic bands, were found to differ. These changes were generally consistent with a pattern of decreasing fat hardness over the November to March period of a typical dairy season.     

Lipid Class and Fatty Acid Composition of Psoralia corylifolia Seed

The purified crude lipid of Psoralia corylifolia seeds was subjected to lipid class and fatty acid analysis by thin layer and gas chromatography. The lipid classes identified were triacyl glycerol, free fatty acid, diacyl glycerol, mono acyl glycerol, hydrocarbon-waxester and polar lipid fractions. Most of the fractions were found to contain high level of C_18:1 while C_18:0, C_18:3 and C_20:0 were also found to be present in all the lipid fractions. It has been observed that the diacyl and monoacyl glycerol fractions contain significant amounts of C_14:0 and C_18:0 while the hydrocarbon-waxester fraction was rich in C_22:0. The polar lipids contain high level of C_18:3 and low level of C_18:1 as compared to other lipid fractions. The fatty acid composition of the whole oil was also determined and found to be similar to other fractions. Unidentified long chain fatty acids were also present in significant amounts in all the lipid fractions.