Lipids of bovine thyroid

The lipid composition of the freshly slaughtered bovine thyroid tissue has been investigated. The phospholipid patterns of microsomal and mitochondrial fractions obtained from homogenates of bovine thyroids have also been determined. They resemble the phospholipid composition of the corresponding subcellular fractions from other tissues. The fatty acid composition of the various phospholipid species of these subcellular components have also been estimated by gas liquid chromatography. These analyses reveal that the fatty acids are not particularly characteristic of the subcellular organelle but tend to be characteristic of the lipid species. There is a high percentage of nervonic acid (C24∶1) in all the subcellular phospholipid species examined.     

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.     

Triacylglycerol composition of Pinus koraiensis seed oil

The triacylglycerol (TG) composition of Pinus koraiensis seed oil, which contains Δ5 nonmethylene-interrupted (NMI) fatty acids (FA) (the main acid is pinolenic, 18:3 Δ5, 9, 12), was determined. TG were preliminarily separated by argentation thin-layer chromatography (TLC), and the obtained fractions were analyzed by high-temperature gas chromatography (GC) on a capillary column with methyl phenyl silicone phase. Additionally, high-performance liquid chromatography (HPLC) of TG was applied. The FA composition of all TG fractions was identified. The identification of TG was carried out by combining TLC, GC, HPLC, and calculated equivalent carbon numbers of TG standards. The TG species identification was confirmed by comparison of the theoretical recalculated and directly analyzed FA compositions of all TLC fractions of TG. Species of TG with unsaturation degrees of 1 to 7 and trace amounts of saturated and octaenoic TG species were found. Except for minor compounds, 26 TG molecular species of 32 main components were quantitatively determined. The main species were oleoyl dilinoleoylglycerol (14.7%), dilinoleoyl pinolenoylglycerol (10.7%), palmitoyl oleoyl linoleoylglycerol (8.3%), triolein (7.6%), and dioleoyl, linoleoylglycerol (7.4%). Seven TG species contained Δ5 NMI acyl groups. Of these, the major were dilinoleoyl pinolenoyglycerol (10.7%), stearoyl linoleoyl pinolenoylglycerol (6.5%) dioleoyl, pinolenoylglycerol (5.4%), and palmitoyl linoleoyl pinolenoyl-glycerol (5.5%). TG species with two or three NMI acyl groups were not detected.     

Chemical Investigations on Celastrus paniculatus Seed Oil I

Fatty acid compositions of four lipid fractions of Celastrus paniculatus seed namely normal triglycerides (20.2%), polar triglycerides (44.4%), polar nonglyceridic ester (23.5%), and nonpolar nonglyceridic ester (11.9%), have been determined by gas liquid chromatography. Percentage contents of major component acids in these fractions are: palmitic, 25.1, 42.0, 12.7, 58.2; stearic, 6.7, 4.5, 15.8; oleic, 46.1, 24.8, 4.7, 14.2; linoleic, 15.4, 14.7, 10.0; and linolenic, 3.0, 13.1, 43.0, respectively. The major molecular species constituting the normal triglycerides are: palmitooleopalmitin, 6.8%; palmitooleostearin, 5.6%; palmitodiolein, 14.7; palmitooleolinolein, 7.0%; stearodiolein, 6.1%; triolein, 8.0% and dioleolinolein 7.6%. Lipolysis of the polar triglyceride indicated as high as 59.6% of saturated acids linked to the 2-position of glycerol.     

Phospholipids of three xerophytic cucurbit seed oils

The composition of seed phospholipids was determined in three species of xerophytic cucurbits,Cucurbita digitata Gray,C. foetidissima HBK andApodanthera undulata Gray. The phospholipid fractions were isolated using silicic acid chromatography and quantitated by colorimetric analysis. The component phospholipids were separated using thin layer chromatography. All three species contained phosphatidylcholine, phosphatidyl-ethanolamine and phosphatidylinositol as their major component phospholipids. Analysis by gas liquid chromatography of fatty acids in total phospholipid samples revealed linoleic acid as the major component and myristic acid in significant amounts in each species. Small amounts of conjugated unsaturated fatty acids in the phospholipids of each species were determined by ultraviolet spectrometry. Close similarities in the composition of specific phospholipids were found in all species. This is Paper No. 3908 of the Arizona Agricultural Experiment Station.     

Fatty acid composition of rat hearts as influenced by age and dietary fatty acids

Fatty acid composition of neutral and polar lipid fractions from rat hearts was determined in rats of different ages as their diet source changed. Piebald rats were weaned at 21 days and were fed standard lab chow. Lipids from rat hearts, mothers milk and lab chow were purified on a Sephadex G-25 fine column and separated into neutral and polar lipid fractions by silicic acid column chromatography. These lipid fractions were then hydrolyzed and methylated with BF₃ in methanol, prior to gas liquid chromatographic separation on a 1/8 in. × 10 ft aluminum column of 15% EGS on 80–100 mesh acid-washed Chromosorb W. Three major fatty acids in the neutral lipid fraction comprised 72% of total neutral lipid fatty acids from young hearts. At sexual maturity (at least 74 days old) C_18∶1 was the major fatty acid, followed by C_16∶0 and C_18∶0. The same three fatty acids comprised 83% of total polar lipid fatty acids, but C_18∶0 was the major fatty acid, followed by C_16∶0 and C_18∶1. The fatty acid composition of dietary lipids influenced the total neutral lipid fatty acid composition of the rat heart, but had little influence on the fatty acid composition of the polar lipid fraction. Presented in part at the AOCS Meeting, New Orleans, April 1970.     

Polar and nonpolar lipids and their fatty acid composition of a fewFusarium species

A few species ofFusarium have been evaluated for their potential to produce lipids. The isolates under investigation exhibited wide variation with respect to the mycelial weight, total lipid content and percentage composition of polar and nonpolar lipids in which triglycerides were the major components (81–90%). Palmitic, stearic, oleic and linoleic acids were the major fatty acids in both the fractions. The polar lipids contained higher levels of linoleic acid, whereas nonpolar lipids contained oleic acid as the predominant acid. Nonpolar lipids were more saturated than polar lipids.     

Combination of thin layer chromatography and gas chromatography in the analysis on a microgram scale of lipids from wheat flour and wheat flour doughs

Lipids were extacted on a microgram scale from 3 to 6 mg flour or from freeze-dried dough by percolation. The impure extract was separated into 12 nonpolar and 14 polar lipids by TLC. Then the fatty acid composition of most of these lipids was determined by gas chromatography. The microscale method renders possible qualitative and quantitative determination of the composition of the lipids in minute quantities of flour and dough. The selectivity of different extraction solvents was studied. In both flour and dough the fatty acid composition of a given component is identical in the free and bound lipid fractions. In dough, the quantity of free lipids is less than in flour; the extent of the decrease depends on the atmosphere in which it is mixed. During mixing, the carotenoid pigments, α-monoglycerides and the free linoleic acid and linolenic acid are oxidized. Oxidation is apparently a function of the concentration of oxygen and of lipoxidase.     

The lipid composition of karaka seeds (corynocapus laevigatus)

The kernels of karaka seeds(Corynocapus laevigatus) contained 9.6% oil by wt. The lipid constituents were characterized by silicic acid column chromatography and thin layer chromatography, and their individual fatty acid compositions by gas liquid chromatography. Of the seed oil, triacylglycerol was the major component which contained high proportions of linoleic (45%) and oleic (26%) acids. The major component of husk oil (0.9% of husk by wt) was polar lipid (glycolipids and pigments).     

Lipid composition of 30 species of yeast

The detailed composition of cellular lipid of more than 23 species of yeast has been determined quantitatively by thinchrography on quartz rods, a method previously used for estimating cellular lipids of seven species of yeast. That data was fortified by neutral and phospholipid quantitations on 30 species of yeast cells. Most of the test organisms contained 7–15% total lipid and 3–6% total phospholipid per dry cell weight, except for the extremely high accumulation of triglycerides in two species ofLipomyces. Qualitatively, 30 species of yeast cells contained similar neutral lipid constituents (triglyceride, sterol ester, free fatty acid, and free sterol) and polar lipid components (phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, phosphatidyl inositol, cardiolipin, and ceramide monohexoside) without minor constituents. Based on the quantitative composition of neutral lipids, the 30 species of yeast were divided into two groups, the triglyceride predominant group and the sterol derivative group. These groupings were fairly well overlapped from the standpoint of the distribution characteristics of fatty acid. The relative polar lipid compositions also grossly resembled each other. Only one exception of polar lipid composition in yeast cells was found inRhodotorula rubra species which contained phosphatidyl ethanolamine as the most abundant phospholipid. Fatty acid distribution patterns in yeast cells consistently coincided with other reports concerning fatty acid composition of yeast cells. Correlation of lipid composition and classification of yeasts are suggested and discussed. A part of this investigation has been reported at the 14th conference of the Japan Oil Chemists' Society, Nagoya, Japan, October 1975.     

Variation in fatty acid composition of the different acyl lipids in seed oils from fourSesamum species

Seeds from different collections of cultivatedSesamum indicum Linn. and three related wild species [specifically,S. alatum Thonn.,S. radiatum Schum and Thonn. andS. angustifolium (Oliv.) Engl.] were studied for their oil content and fatty acid composition of the total lipids. The wild seeds contained less oil (ca. 30%) than the cultivated seeds (ca. 50%). Lipids from all four species were comparable in their total fatty acid composition, with palmitic (8.2–12.7%), stearic (5.6–9.1%), oleic (33.4–46.9%) and linoleic acid (33.2–48.4%) as the major acids. The total lipids from selected samples were fractionated by thin-layer chromatography into five fractions: triacylglycerols (TAG; 80.3–88.9%), diacylglycerols (DAG; 6.5–10.4%), free fatty acids (FFA; 1.2–5.1%), polar lipids (PL; 2.3–3.5%) and steryl esters (SE; 0.3–0.6%). Compared to the TAG, the four other fractions (viz, DAG, FFA, PL and SE) were generally characterized by higher percentages of saturated acids, notably palmitic and stearic acids, and lower percentages of linoleic and oleic acids in all species. Slightly higher percentages of long-chain fatty acids (20∶0, 20∶1, 22∶0 and 24∶0) were observed for lipid classes other than TAG in all four species. Based on the fatty acid composition of the total lipids and of the different acyl lipid classes, it seems thatS. radiatum andS. angustifolium are more related to each other than they are to the other two species.     

Lipid metabolism ofAgaricus bisporus (Lange) sing.: I. Analysis of sporophore and mycelial lipids

The lipid components of four strains ofAgricus bisporus (Lange) Sing., the cultivated mushroom, were analyzed. Both sporophore and mycelial samples were obtained from beds in normal production. A method for obtaining mycelium free of compost was developed. Neutral lipids were separated from polar lipids by silicic acid column chromatography. Each fraction was separated by thin layer chromatography. Fatty acid methyl esters were analyzed by gas liquid chromatography and mass spectrometry. Sporophore extracts contained free sterol, free fatty acid, triglycerides, phosphatidyl choline and phosphatidyl ethanolamine. High amounts of linoleic acid were found in both neutral and polar lipid fractions. Mycelial extracts contained free fatty acids, triglycerides, phosphatidylcholine and phosphatidyl ethanolamine. No free sterol could be detected. Linoleic acid was also present in large amounts. Paper 3798 in the Journal Series of The Pennsylvania Agricultural Experiment Station.     

Polyunsaturated fatty acids and neutral lipids in developing larvae of the oyster,Crassostrea virginica

The fatty acid composition of oyster larvae at various stages, as well as of the algal diet, were determined by gas liquid chromatography (GC). Saturated fatty acids are the major fatty acid components in all larval stages and account for 34–62%, 30–35% and 35–81% of the neutral, polar and total lipids of algal-fed larvae respectively. Weight percentage of saturated fatty acid in “starved” larvae was consistently higher (63–81%) during the whole period. The total polyunsaturated fatty acids were higher in the polar lipids than in the neutral lipids. The concentration of the ω3 fatty acids also was comparatively higher in the polar lipids than in the neutral lipids. In the total and neutral lipid fractions, the weight percentage of polyunsaturated and ω3 fatty acids was higher in the eyed than in the pre-eyed (pediveliger) larvae. Eicosapentaenoic acid (20∶5ω3) and 22∶6ω3 were not detected in lipids of “starved” and young larvae. There was an accumulation of 20∶5ω3, 22∶6ω3, and total ω3 fatty acids in the older larvae. Lipid classes were separated by thin layer chromatography (TLC). There was no qualitative change in lipid composition during larval development, but a marked increased of triacylglycerol in larvae up to the stage of maturation in algae-fed larvae. Contribution number 1195 of the Virginia Institute of Marine Science, Gloucester Point, VA 23062     

Chromatography of polar triglycerides on silicic Acid Columns

Triglycerides containing polar fatty acids are resolved by silicic acid chromatography into molecular species containing increased amounts of the polar acids. Natural fats like isano, oiticica, castor, or kamala seed oils with both nonpolar fatty acids and polar hydroxy or keto acids have been resolved into component glycerides according to the degree of polarity. Silicic acid chromatography offers a means of obtaining specific glycerides from fats for detailed studies on glyceride composition and structure. Presented at the AOCS Meeting, Cincinnati, October 1965. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Fatty acid composition of seeds from the AustralianAcacia species

Presented are the lipid content and fatty acid composition of 20 species of edible AustralianAcacia seeds. Aborigines reportedly have used at least 18 of these as foods. Seed lipid content ranged from 3% to 22%, with an average of 11% on a dry weight basis. Linoleic (12–71%), oleic (12–56%) and plamitic (7–35%) acids were the major fatty acids. Smaller proportions of behenic, stearic and vaccenic acids were detected. Seventeen of the 20 species were found to have polyunsaturated to saturated (P/S) fatty acid ratios greater than 1, with four species having ratios in excess of 4. The persistent arils attached to the seeds of certain AustralianAcacias and containing a portion of the total lipid were associated with a significantly reduced proportion of linoleic acid in the total seed material. This observation was explained by the aril lipid possessing a markedly different fatty acid composition from that of the seed lipid. For comparison, seeds from two non-AustralianAcacia species (A. farnesiana andA. cavenia) were analyzed. Australian and non-Australian were found to exhibit markedly different fatty acid profiles. Some of this work published as short report inProc. Nutr. Soc. Aust. 10, 209–212 (1985).     

Composition of total lipids in rapeseed

Total lipids in medium and low erucic acid cul-tivars of rapeseed(Brassica napus var. Sinus and Janpol, resp.) were fractionated into polar and non-polar constituents. Triglycerides, diglycerides, mono-glycerides, free fatty acids, sterol esters, sterols, phos-pholipids and glycolipids were quantitated and their fatty acid compositions determined. Triglycerides and phospholipids constituted 92 and 3.4%, resp., of the total lipid from each cultivar. Triglycerides were lower in saturated fatty acids but higher in monoun-saturated acids and linolenic acid than other lipid fractions. Phospholipids and glycolipids were higher in linoleic acid content than other lipid classes. Generally, the reduction in long chain, monoenoic, fatty acids was associated with a corresponding increase in oleic acid in most low erucic acid frac-tions.     

Preparation of Fatty Acid Methyl Esters by Selective Methanolysis of Polar Glycerolipids

KOH in aqueous methanol catalyzes selective methanolysis of polar glycerolipids with O-ester-linked acyl residues, while triacylglycerols and sterol esters are inert in the solution. Based on these findings, a convenient and reliable method was developed for the preparation of fatty acid methyl esters (FAMEs) from polar glycerolipids in lipid mixtures without prior isolation. Methanolysis of polar glycerolipids was completed within 2.5 min by vortexing or 20 min by shaking with 0.7 M KOH/70% (v/v) methanol in the presence of hexane at 30 °C. The yields of FAMEs obtained by the present method were greater than 95%. The method was applied successfully to gas chromatographic analysis of the fatty acid compositions of polar glycerolipids in seed oil and blood. No obvious differences were found between the fatty acid compositions determined by the present method and those determined by conventional methods, including lipid extraction with chloroform/methanol followed by isolation of polar lipids by chromatography. The fatty acid composition of polar glycerolipids, including phospholipids, can be determined readily in many crude samples.     

Chromatographic characterization of internal polar lipids from wool

Wool internal polar lipids were isolated and separated into different fractions based on polarity. Qualitative and quantitative analyses of the different fractions were performed by thin-layer chromatography and thin-layer chromatography coupled to flame-ionization detection, respectively. Cholesterol esters, free fatty acids, sterols, ceramides, glycosylceramides, and cholesterol sulfate were the main components, with ceramides being in the highest proportion. The fatty acid composition of ceramides and glycosylceramides was determined by gas chromatography/mass spectrometry. As for other keratinized tissues, long-chain fatty acids predominated in comparison to either free fatty acids or phospholipid-linked fatty acids; in both cases, stearic and lignoceric acids were the most abundant fatty acids, and a low amount of 18-methyleicosanoic acid was found. This work opens new avenues in the study of lipid rearrangement in more complex and realistic vesicle structures than conventional liposomes.     

The endosperm lipids of three Canadian wheats

Flour samples were prepared from intact and degermed kernels of Hard Red Spring, Soft White Spring, and Amber Durum wheats. The “free” (hexane soluble) and “bound” (hexane resistant, water-saturatedn-butanol extractable) lipids were extracted from the six flours and separated quantitatively by silicic acid column chromatography. Thin-layer chromatography (TLC) was used to monitor the column and to resolve the lipid classes into components. Gas-liquid chromatography (GLC) was used to obtain the fatty acid composition of the triglyceride, sterol ester, and phospholipid fractions, and also to determine the nature of the sterol components of the unesterified sterol and sterol ester classes. Similar patterns of lipid classes were shown by all three varieties; the differences were in the degree of dominance. In fatty acid composition some varietal differences were found but the greatest difference was between lipid classes. Contribution No. 5 of the Food Research Institute. Presented at the AOCS Meeting, Toronto, 1962.     

Lipids ofEchinococcus granulosus protoscolices

The fatty acid composition of the triglyceride and the total phospholipid fractions of ovine liverEchinococcus granulosus protoscolices was determined by gas chromatography and compared with that of the healthy and Echinococcus infected livers. The chain length of the major saturated fatty acids identified in both the host tissues and the parasite ranged from 12–22 carbons. Oleic and linoleic acids were the only detectable unsaturated fatty acids identified in protoscolices and the liver samples. Comparison of the amounts of the fatty acids from the three different sources mentioned above by analysis of variance and the contrast method of Scheffe, revealed a significant decrease in the level of oleic acid in triglyceride fraction of the infected livers compared with normals. Thinlayer chromatography of the polar lipid fraction of the protoscolices resulted in tentative identification of lysolecithin, sphingomyelin, lecithin, phosphatidyl inositol, sulfatides, cerebrosides, cephalins and cholesterol.