The fatty acid composition of some entomophthoraceae

Lipids extracted fromConidiobolus denaesporus Drechsl. were found to contain three branched-chain fatty acids, which together comprised about 35% of the total fatty acids of the fungus. The branchedchain acids were identified by gas-liquid chromatography, infrared and mass spectroscopy as 12-methyl tridecanoic, 12-methyl tetradecanoic, and 14-methyl pentadecanoic acids respectively. Then-saturated acids comprise C12, C13, C14, C16, and C18. Then C16,n C18, andn C20 unsaturated acids were also found. The occurrence of 15.2% of myristic acid and of 8.9% of eicosatetraenoic acid provides a further distinctive feature of the lipids ofConidiobolus denaesporus. Contribution No. 94.     

The control of fatty acid composition in glycerolipids

The continued suggestion that the ratio of saturated to unsaturated acids in the diet can influence the general health of a mammal is still not easily explained at a biochemical level. Studies on the metabolism of glycerophosphatides show that the enzymes involved appear to differ in the degree of selectivity toward substrates with different amounts of unsaturation. In general, each individual acid will have its own characteristic metabolic fate. The acyl-CoA:acyl-GPC acyltransferases have a marked specificity for both the position to be acylated and the particular acyl-CoA involved. In some cases, the observed distributions of fatty acids in naturally occurring lecithins and triglycerides are similar to the distributions predicted from in vitro studies of the acyltransferase enzymes. Other enzymatic steps, such as acid activation and N-methylation, can also be shown to influence the fatty acid composition of the glycerolipids. The relative importance of these metabolic processes must now be determined.     

The fatty acid composition of various cruciferous seeds

Seeds from 26 Cruciferae species in 7 genera have been investigated for fat content and fatty acid composition of the oil. The GLC retention data have been verified by mass spectrometry. The oil from Cardamine graeca contained 54% of cis-15-tetracosenoic acid; it is the highest content of this acid so far reported in any seed fat.     

The fatty acid composition of the seeds ofGinkgo biloba

The fatty acid composition of seeds ofGinkgo biloba has been examined by a combination of capillary gas chromatography, silver ion high-performance liquid chromatography and gas chromatography/mass spectrometry. Some of the fatty acids identified are unusual in plants and were rather different from those reported earlier. These include ananteiso-methyl branched fatty acid, 14-methylhexadecanoic acid, 5,9-octadecadienoic acid, and 5,9,12-octadecatrienoic acid. Fourier-transform infrared spectroscopy confirmed that all of the double bonds were of thecis-configuration.     

The fatty acid composition of edible marine fish oils

The body oils of 13 species of marine edible fishes found around the Karachi-Makran coast were studied by gas-liquid chromatography (GLC) for their fatty acid composition. The analyses showed the presence of fatty acids with chain lengths from 10 to 24 carbon atoms and with zero to six double bonds. The oils were found to be rich in polyunsaturated acids, particularly the penta- and hexaenoic. Certain major fatty acids were found to vary widely among the species: myristic acid 2.3 to 13.7%; palmitic 11.6 to 41.2%; stearich 7.2 to 23.2%; oleic 6.9 to 29.6%; eicosapentaenoic 1.4 to 19.0%; docosapentaenoic zero to 10.2%; and docosahexaenoic zero to 36.4%. The linoleic and linolenic acids were present in small amounts in some of the fish oils, and arachidonic acid was present in all of them.     

Phospholipid fatty acid composition and stereospecific distribution of soybeans with a wide range of fatty acid composition

Phospholipid (PL) fatty acid composition and stereospecific distribution of 25 genetically modified soybean lines with a wide range of compositions were determined by gas chromatography and phospholipase A₂ hydrolysis. Pl contained an average of 55.3% phosphatidylcholine, 26.3% phosphatidylethanolamine, and 18.4% phosphatidylinositol. PL class proportions were affected by changes in overall fatty acid composition. PL fatty acid composition changed with oil fatty acid modification, especially for palmitate, stearate, and linolenate. Stereospecific analysis showed that saturated fatty acids were primarily located at the sn-1 position of all PL, and changes of the saturates in PL were largely reflected on this position. Oleate was distributed relatively equally between the sn-1 and sn-2 positions. Linoleate was much more concentrated on sn-2 than on sn-1 position for all PL. Linolenate was distributed relatively equally at low concentration but preferred sn-2 position at high concentration.     

The effect of fatty acid composition on biodiesel oxidative stability

Concerning their environmental impact, native based fuels and lubricants show immense potential. In fact, these products are highly exposed to oxidative processes during storage or application [1, 2]. One way to raise oxidative stabilities is the addition of synthetic antioxidants. Another way may be the modification of the fatty acid composition, since polyunsaturated fatty acids show a much higher proneness to autoxidation. In order to decrease the content of polyunsaturated and to raise the content of saturated components, experiments for fractional distillation and crystallisation as well as for hydrogenation of fatty acid methyl esters have been carried out. In distillation experiments with separation columns the methyl esters performed good separation of the lower‐boiling esters with a chain‐length up to 16C‐atoms, from the C‐18 fraction, causing a degree of saturation up to 75 wt‐% in the distillate. In tests with fractional crystallisation, the rate of saturation could be raised up to 92.8 wt‐%. Using the process of catalytic hydrogenation, a rate of saturation up to 100 wt‐% could be achieved, depending on the duration of the hydrogenation process. By partial hydrogenation of the polyunsaturated components, products with high oxidation stability and low pour point could be produced within relatively short hydrogenation time.     

The fatty acid composition of gymnospermae seed and leaf oils

Of 12 Gymnospermae seed and leaf oils, only 2 contained cyclopropene fatty acids. All-cis 5, 11, 14, 17-eicosatetraenoic acid occurred in concentrations up to 11.9% in 6 seed oils, and up to 61% in 2 leaf oils. The structure of this acid, as its methyl ester, was established by the combination of physical (UV, IR,¹H- and¹³C-NMR and mass spectra) and chemical techniques. Arachidonic acid also occurred in 2 seed oils.     

The fatty acid composition of purified fractions of cold-pressed peanut oil

Cold-pressed peanut oil was separated into chromatographically homogeneous fractions by column chromatography. The fatty acid composition of the major fractions was determined by gas chromatography. The phosphatides, and especially the cephalins, had a higher palmitate content than did the triglycerides. Palmitate was the dominant fatty acid in the phosphatidyl-serines.     

The fatty acid composition of the seed fat from Swietenia macrophylla

Summary A light yellow oil was isolated in 50% yield from the decorticated seeds ofSwietenia macrophylla kina grown in India. The unrefined oil had a slightly bitter taste and an iodine value of 109.7. Other properties are reported. By means of spectrophotometry, fractional crystallization, and methyl ester distillation, the oil was found to have the following fatty acid composition (as %): palmitic, 12.50; stearic, 16.42; arachidic, 0.56; oleic, 25.30; linoleic, 33.87; linolenic, 11.32. These values for linoleic and linolenic acid differ considerably from those previously reported for an oil from the same species grown in Mexico.     

Determination of fatty acid composition of amaranthus species

Fatty acid compositions of the seed oils from eighteen vareties of amaranthus species have been determined after room temperature transesterification. Consistent with earlier studies, wide variations in the fatty acid composition are reported, and appear to be agronomically related. All variaties show significant levels (2–5%) of squalene and a combined linoleic acid and olaic acid occurrence of between 70–-80%. This study represents the frist reported fatty acid composition of grain amaranthus cultivated in West Africa.     

Improving the fatty acid composition of soybean oil

Efforts to improve the composition of soybean oil by breeding the beans for low linolenic acid in the oil have continued since 1968. This paper reports recent work using hybrid crosses and induced mutations. No lines are yet available that contain oil having less than 3% linolenic acid. Journal Paper No. J-11466 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project No. 2475.     

Altered fatty acid desaturation and microsomal fatty acid composition in the streptozotocin diabetic rat

Streptozotocin diabetes in the rat diminishes the synthesis of both monounsaturated and polyunsaturated fatty acids. Rat liver microsomal fatty acid composition and fatty acid desaturation were studied in the streptozotocin diabetic rat. The major alterations in fatty acid composition found in the diabetic rat were decreased proportions of palmitoleic, oleic and arachidonic acids and an increased proportion of linoleic and docosahexaeneoic acids. These findings, other than the increased docosahexaeneoic acid, probably result from the diminished liver microscomal δ9 and δ6 desaturase activities found in these animals. These changes are not due to the diminished weight gain of the diabetic animals since restricting food intake of control animals to achieve a similar weight gain failed to reproduce either the changes in fatty acid composition or the decrease in fatty acid desaturation. The increased food intake of the diabetic animal may contribute to the altered proportions of linleic and arachidonic acids since limiting food intake in diabetic animals to that of normal controls diminished the magnitude of these changes. Insulin therapy for 2 days not only reverses and overcorrects the diminished desaturase activities, but likewise reverses and overcorrects the altered fatty acid composition, with the exception of the diminished arachidonic aicd levels which are further decreased following insulin therapy. These findings strongly suggest that most of the changes in fatty acid composition in the diabetic rat are indeed caused by the diminished fatty acid desaturase activities.     

Cyclopropenoid fatty acid content and fatty acid composition of crude oils from twenty-five varieties of cottonseed

The cyclopropenoid acid content of oils extracted from 22 commercial varieties and 3 botanical species of cottonseed have been determined. The malvalic acid content determined by HBr titration varied from a low of 0.56% to a high of 1.17%. Iodine values of the oils ranged from 96.8 to 111.6 No definite correlation could be established between iodine value and malvalic acid content. Equations for regression lines for the major acids have been calculated from plots of fatty acid composition vs. iodine value. The high degree or correlation suggests that for commercial oils the fatty acid composition can be estimated from the iodine value. Oils of the 3 experimental types of different species showed wide variations in fatty acid composition and represented many of the maximum and minimum values reported. So. Utiliz. Res. Dev. Div., ARS, USDA. ARS, USDA.     

Cyclopropenoid fatty acid content and fatty acid composition of crude cottonseed oils from successive solvent extractions

The fatty acid composition and properties of six fractions of oil successively extracted from cottonseed meats has been investigated. The cyclopropenoid fatty acid concn increased regularly from 0.30–1.06%, a 3.5-fold increase. This suggests that the cyclopropenoid constituents of the oil in the seed are less accessible to the solvent. The linoleic acid concn decreased from 56.3–53.1% accounting for a slight reduction in iodine value (I.V.). The first two fractions had a markedly lower phosphatide content than the remaining fractions. Presented at the AOCS Meeting in Chicago, 1964. A laboratory of the So. Utiliz. Res. & Dev. Div., ARS, USDA.     

The influence of dietary fatty acids and environmental temperature on the fatty acid composition of teleost fish

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. Examination of the tissue fatty acids demonstrated that marine and fresh water fish do not differ between themselves or from other classes of animals in the following basic mechanisms of deposition and interconversions of dietary fatty acids:

1. 1)
   The fish are readily depleted of tissue polyunsaturated fatty acids.     
   
   

Analysis and fatty acid composition of tobacco seed oils

Summary THE fatty acid compositions of twelve samples of oil representing a number of different types and varieties of tobacco were determined by the thiocyanometric method. The samples were remarkably uniform in composition, containing on the average 75% linoleic, 15% oleic, and 10% saturated acids. Spectrophotometric determination of the linoleic acid content of two samples of oil gave values 3.0 and 5.4% higher than those by the thiocyanometric method. A more complete investigation of the fatty acid constituents of one sample of flue-cured tobacco seed oil was carried out by analysis of fractions obtained by distillation of the methyl esters and by low-temperature crystallization of the distilled ester fractions. The composition calculated from these analyses agreed well with that determined from analysis directly on the oil. The saturated acids consisted of palmitic and stearic acids, the proportions being about 7 and 3%, respectively, of the total fatty acids. Analysis of this sample of oil showed that it contained 0.043% of tocopherol. From its composition, tobacco seed oil would seem to be particularly suitable for the manufacture of nonyellowing alkyds or for the preparation of technical linoleic acid. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, United States Department of Agriculture.     

Phospholipid content and fatty acid composition of human heart

Phospholipid content and fatty acid composition of human heart were determined on 36 biopsy specimens collected during open heart surgery. The main phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and sphingomyelin (SPH) were separated by HPLC, quantified, and converted to fatty acid methyl esters which were chromatographed on capillary GLC columns. Sex and age (mainly 40–70) of patients had no significant influence on the relative distribution of phospholipid classes and only a slight effect on fatty acid composition. Incorporation oftrans 18∶1 in phospholipid classes was low.cis andtrans octadecenoic isomers seemed to be selectively incorporated, the Δ9 and Δ11cis ortrans isomers being predominant. Human and rat data were compared, and some species differences were noticed. In human PC, palmitic acid is higher and stearic acid much lower than in rat PC. Saturated dimethyl acetals (16∶0 and 18∶0) in PC and PE were greater for humans. Incorporation of 20∶4 n−6 in human PE is higher than in rat PE.     

Tocopherol and fatty acid composition of some Indian pulses

The tocopherol and tocotrienol composition of the Indian pulses Bengal gram (Cicer arietinum L.), blackgram (Vigna mungo L.), green gram (Vigna radiata L.), and horse gram (Dolichos biflorus L.) were studied. The total tocopherol content ranged from 230 to 1567 mg/100 g fat, while the tocopherol content of the pulses as a whole ranged from 6.76 to 12.54 mg/100 g seed. Presence of such a high amount of tocopherol, both in the oil fraction of Indian pulses and in an oil fraction of a food material, is being reported for the first time. The fatty acid composition of the fat extracted from these pulses showed substantial amounts of unsaturated fatty acids (Bengal gram, 88.7%; black gram, 82.9%; green gram, 64.3%; and horse gram, 66.9%). These pulses contained 3.8 to 49.1% linolenic acid in the fat.