Excess molar enthalpies of binary mixtures containing esters of fatty acids

1988 ◽  
Vol 66 (5) ◽  
pp. 1283-1287 ◽  
Author(s):  
Santos Otin ◽  
Ignacio Senar ◽  
Ma José Soriano ◽  
Celso Gutierrez Losa

Excess molar enthalpies [Formula: see text] at 310.15 K and 101.32 kPa, have been determined for the binary mixtures: lauric acid ethyl ester +, stearic acid ethyl ester +, oleic acid ethyl ester +, linoleic acid ethyl ester + n-hexadecane, + toluene, or + ethyl alcohol, and elaidic acid ethyl ester + n-hexadecane or + toluene.The results show that HE of ester + n-hexadecane mixtures increases with decreasing chain length and with increasing unsaturation of the ester molecule. Ester + toluene mixtures are slightly exothermic and ester + alcohol are strongly endothermic, with [Formula: see text] values ranging from 1535 to 1740 J mol−1 at the maximum.


1986 ◽  
Vol 59 (5) ◽  
pp. 800-808 ◽  
Author(s):  
James M. Sloan ◽  
Michael J. Maghochetti ◽  
Walter X. Zukas

Abstract An effort to characterize the reversion process of guayule rubber when naturally-occurring guayule resin components are present has shown that these components act as a reversion-retarding material. The amount of reversion resistance varies as a function of temperature, concentration, and type of fatty acid. Of the three fatty acids used, linoleic acid, stearic acid, and oleic acid, linoleic acid performed the best for reversion resistance, followed by stearic acid, then oleic acid. When the temperature was increased 10°C, an increase of 15% reversion was observed. This held true for the three temperatures studied. In addition, the amount of reversion improvement upon addition was 20% reversion. In the case of curing at 150°C, this resulted in 0% reversion. The 20% resistance improvment was consistent for the 3 temperatures studied.



2012 ◽  
Vol 7 (10) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
Rashmi Kumari ◽  
Gopal Rao Mallavarapu ◽  
Vinod Kumar Jain ◽  
Sushil Kumar

Fatty oils of the seeds of Cleome viscosa accessions from Delhi, Jaipur, Faridabad, Surajkund and Hyderabad were methylated and analyzed by GC and GC-MS. The major fatty acids, identified as their methyl esters, of the oils from these five locations were palmitic acid (10.2-13.4%), stearic acid (7.2-10.2%), oleic acid (16.9-27.1%) and linoleic acid (47.0-61.1%). In addition, palmitoleic acid, octadec-(11 E)-enoicacid, arachidic acid, eicosa-(11 Z)-enoic acid, linolenic acid, heneicosanoic acid, behenic acid, lignoceric acid, pentacosanoic acid, hexacosanoic acid, 12-oxo-stearic acid, and the alkanes tetracosane, pentacosane, hexacosane, heptacosane, octacosane, nonacosane, triocontane, hentriacontane and dotriacontane, were also identified as minor and trace constituents in some of these oils.



Author(s):  
Vilcacundo E ◽  
Alvarez M ◽  
Silva M ◽  
Carpio C ◽  
Morales D ◽  
...  

 Objective: The aim of this study was to determine the fatty acids composition in a tocte seeds oil (Juglans neotropica Diels) sample cultivated in Ecuador.Methods: Tocte oil was obtained from tocte seeds using the cold pressing method. Fatty acids analysis was carried out using the gas chromatography method with a mass selective detector (GC/MSD) and using the database Library NIST14.L to identify the compounds.Results: Methyl esters fatty acids were identified from tocte (J. neotropica Diels) walnut using the GC–MS analytical method. The total lipid content of tocte walnuts seeds of plants cultivated in Ecuador was of 49.01% of the total lipid content on fresh weight. Fatty acids were analyzed as methyl esters on a capillary column DB-WAX 122-7062 with a good separation of palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. The structure of methyl esters fatty acids was determined using the GC–MS. Tocte walnut presents 5.05% of palmitic acid, 2.26% of stearic acid, 19.50% of oleic acid, 65.81% of linoleic acid, and 2.79% linolenic acid of the total content of fatty acids in tocte oil. Fatty acids content reported in this study were similar to the data reported for other walnuts seeds.Conclusions: Tocte seeds are a good source of monounsaturated and polyunsaturated fatty acids. Tocte oil content oleic acid and with a good content of ɷ6 α-linoleic and ɷ3 α-linolenic. Tocte walnut can help reduce risk cardiovascular diseases in Ecuador for their good composition of fatty acids.



1970 ◽  
Vol 42 (1) ◽  
pp. 75-78 ◽  
Author(s):  
M Mostafa ◽  
Momtaz Ahmed ◽  
Ismet Ara Jahan ◽  
Jasim Uddin Choudhury

The oil obtained from the seeds of Cassia sophera Linn was analyzed by GC-MS and a total of 42 compounds have been identified. The major constituents are palmitic acid (22.82 %), linoleic acid (8.32 %), elaidic acid (19.16 %), stearic acid (9.86 %), 5-isopropyl -6-methyl-3-heptyne-2,5-diol (6.44 %), undecyl lauric acid (6.61 %), oleic acid (2.1 %), arachidic acid (3.57 %) and 3α, 7β-dihyodxy -5β, 6β-epoxycholestane (5.9 %). Bangladesh J. Sci. Ind. Res. 42(1), 75-78, 2007



Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3277-3277
Author(s):  
Lisa J Robinson ◽  
Janelle Zacherl ◽  
Harry C Blair ◽  
Stephanie J Mihalik

Abstract Abstract 3277 In recent decades, addition to the diet of synthetically hydrogenated vegetable oils has markedly increased human consumption of trans fatty acids. Epidemiological studies have linked this change in diet to current high rates of atherosclerotic cardiovascular disease. Despite recognition of this important connection, the basic mechanisms by which trans fatty acids contribute to the pathogenesis of atherosclerosis are still not well understood. In the present studies we examined the effects of trans fatty acids on macrophage functions and their possible role in the pathogenesis of atherosclerosis. Human macrophages, derived from peripheral blood mononuclear cells, were treated with the trans fat elaidic acid (C18:Δ9–10 trans), the corresponding cis fatty acid oleic acid (C18:Δ9–10 cis), or the saturated fatty acid stearic acid (C18:0). We examined changes in macrophage fat metabolism using GC/MS to measure cell fatty acid content and intermediates, and MS/MS to identify acylcarnitine derivatives, and assayed fatty acid oxidation using fatty acids radiolabeled at the [1–14C] position and the double bond at the [C9-C103H] position. After 44 hours treatment with 100 micromolar elaidic acid, macrophages showed an accumulation of multiple unsaturated fatty acid intermediates, both long-chain and short-chain, by GC/MS analysis, that were not observed in cultures containing either oleic or stearic acid. Using acylcarnitine analysis, we observed an increase in C12 and C18 intermediates in the macrophages exposed to trans fat (either as fatty acids or partially hydrogenated soy oil) compared to controls. These results suggest a block in acyl-CoA removal one group proximate to the trans bond. Beta-oxidation assays using carbon-1 radiolabeled oleic and elaidic acids revealed enhanced entry of the trans-fat into the catabolic cycle compared to the entry of the natural cis-fatty acid. Using carbon 9–10 radiolabeled oleic acid to study oleic acid catabolism, we discovered that in the presence of the trans fat, oxidation of the cis fat was diminished. Thus, in addition to the block in the catabolism of the trans fat itself, the degradation of the cis monounsaturated fatty acids are also impaired in the presence of the trans fat. We then examined the effects of inhibited fatty acid catabolism on macrophage function by examining changes in gene expression. Initial results from Affymetrix gene expression profiling, were confirmed using quantitative real time PCR. These studies revealed that exposure to trans fatty acid, compared to cis fatty acids, markedly upregulated macrophage expression of interleukin 1 beta, an inflammatory cytokine previously implicated in the pathogenesis of atherosclerosis. Also increased was expression of heparin-binding epidermal growth factor, previously implicated as a stimulus for vascular smooth muscle proliferation in atherosclerosis. The results overall suggest that the deleterious effects of trans fats may be linked to impaired macrophage fatty acid catabolism, contributing to lipid accumulation in the atheroma, and also to increased macrophage production of inflammatory mediators. Disclosures: No relevant conflicts of interest to declare.



2018 ◽  
Vol 2 (1) ◽  
pp. 41-53
Author(s):  
Nosa Septiana Anindita dkk

Six probiotic candidates were grown overnight at 37 °C in De Man Rogosa Sharpe(MRS) broth supplemented with 0.4 mg/mL of linoleic acid. The concentrations of the metabolite products in the culture media were determined using GC-MS after extraction and direct transesterification of the fatty acids. Linoleic acid was added to the sample as an internal standard. The result showed that Lactobacilluscasei strainAPwas able to convertfreelinoleicacidto conjugated linoleic acid in themedia more than 60% while five other potential probiotics such as Lactobacillus casei AF, Lactobacillus casei AG, Pediococcus acidilactici AA, Pediococcus acidilactici BE and Pediococcus acidilactici BK have abilities to convert free linoleic acid to palmitic acid, stearic acid and oleic acid with varying percentages.



2016 ◽  
Vol 69 (4) ◽  
Author(s):  
Józef Klocek ◽  
Magdalena Szwed ◽  
Danuta Koczkodaj ◽  
Joanna Mitrus ◽  
Marian Saniewski ◽  
...  

The effect of methyl jasmonate (MJ) vapors on the composition and peroxidation of major fatty acids in the organs of common buckwheat seedlings was investigated. The composition of fatty acids in the hypocotyl and cotyledons of seedlings changed significantly under exposure to MJ vapors in closed jars. Four-day exposure to MJ led to a significant reduction in the concentrations of stearic, linoleic, and linolenic acids in the hypocotyl, whereas oleic acid levels increased approximately 3.5-fold. A decrease in stearic acid levels and an increase in the content of linolenic acid were noted in cotyledons, whereas oleic acid levels decreased in roots. Seven-day exposure to MJ vapor caused a further reduction in stearic acid content and an increase in oleic acid and linoleic acid levels in the hypocotyl. At the same time, the linoleic acid content of roots and linolenic acid levels in cotyledons were doubled, but a 5-fold reduction in linolenic acid concentrations was observed in roots. Methyl jasmonate intensified fatty acid peroxidation in cotyledons after 4 and 7 days and in roots after 4 days of exposure. Peroxidation was inhibited in the hypocotyl and roots after 7 days. The noted changes in the composition and peroxidation of fatty acids are probably indicative of senescence in buckwheat seedlings under the influence of MJ. Senescence seems to proceed faster in cotyledons than in other organs of buckwheat seedlings.



Jurnal Kimia ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 82
Author(s):  
M. H. Rachmawati ◽  
H. Soetjipto ◽  
A. Ign A. Ign. Kristijanto

Overripe tempe is a food product that used by peoples in Indonesia as a food seasoning. So far, overripe tempe received less attention than fresh tempe and research of overripe tempe is rarely done. The objective of the study is to identify the fatty acid compounds of the  fifth day fermentation overripe tempe oil before and after purification . The overripe tempe oil of fifth day fermentation was extracted with soxhletation method using n – hexane solvent, then it was purified. The various fatty acids  of overripe tempe oil were analyzed by GC – MS. The purification process was done by using H3PO4 0,2% and NaOH 0,1N. The result of the study showed that before purification the oil  was composed of eight compounds  are palmitic acid (13,33%),  linoleic acid (77,57%), stearic acid (6,15%), and the five chemical components, Dasycarpidan – 1 - methanol, acetate ,  oleic acid, 9 - Octadecenamide ,Cholestane - 3, 7, 12, 25 - tetrol, tetraacetate, (3?, 5?, 7?, 12?) and  6, 7 – Epoxypregn – 4 – ene -9, 11, 18- triol - 3, 20 - dione, 11, 18 – diacetate have percentage of areas less than 3%. After purification the oil  was composed of palmitic acid (12,38% ), linoleic acid (80,35 %), stearic acid (5,84%), and 17 – Octadecynoic acid (1,42 %) .



2019 ◽  
Vol 54 (4) ◽  
pp. 367-374
Author(s):  
MO Aremu ◽  
AA Waziri ◽  
FJ Faleye ◽  
AM Magomya ◽  
UC Okpaegbe

There are several underexploited plant seeds or fruits in Nigeria with little information about their chemical composition. To this end a comprehensive study on fatty acid, phospholipids and phytosterols composition of bitter melon (Momordica charaantia) fruit and ebony tree (Diospyros mespiliformis) fruit pulp were determined using standard analytical techniques. The most concentrated fatty acid (%) was linoleic acid in Momordica charantia fruit (45.47) and 44.82 in Diospyros mespiliformis fruit pulp. The increasing order of the concentrated fatty acids in Momordica charantia fruit were: linolenic acid (2.38) < stearic acid (7.52) < oleic acid (20.18) < palmitic acid (23.64) < linoleic acid (45.47) while that of Diospyros mespiliformis fruit pulp were: linolenic acid (5.73) < stearic acid (8.62) < oleic acid (18.95) < palmitic acid (20.88) < linoleic acid (44.82). Arachidonic, arachidic, palmitoleic, margaric, behenic, erucic, lignoceric, myristic, lauric, capric and caprylic acids were present in small quantities with none of them recording up to 1.0% in both of the two samples. The results also showed low concentration of monounsaturated fatty acids (MUFA) (20.41%) in Momordica charantia fruit and 19.13% in Diospyros mespiliformis fruit pulp, and values of polyunsaturated fatty acid (PUFA) were 2.44 and 5.78% for the two samples, respectively. The respective phospholipids composition showed a highest concentration of phosphatidylcholine in Momordica charantia and Diospyros mespiliformis (100.31and 88.12 mg/100 g) while lysophosphatidylcholine and phosphatidic acid were the least concentrate values of 12.62 and 14.52 mg/100 g in Momordicacharantia and Diospyros mespiliformis, respectively. The concentrations of phytosterols were of low values except in sitosterol with values of 153.28 and 119.46 mg/100 g in Momordica charantia and Diospyros mespiliformis, respectively. This study provides an informative lipid profile that will serve as a basis for further chemical investigations and nutritional evaluation of Momordica charantia fruit and Diospyros mespiliformis fruit pulp. Bangladesh J. Sci. Ind. Res.54(4), 367-374, 2019



1980 ◽  
Vol 191 (2) ◽  
pp. 637-643 ◽  
Author(s):  
William W. Christie ◽  
Margaret L. Hunter

The effects of inclusion of different fatty acids in the medium on the rate of esterification of palmitic acid and its stereospecific distribution among the three positions of the triacyl-sn-glycerols by preparations of rat adipocytes in vitro have been determined. Myristic acid, stearic acid, oleic acid and linoleic acid were used as diluents and the concentration of the combined unesterified fatty acids in the medium was held constant; only the proportion of palmitic acid was varied. The amount of palmitic acid esterified was always linearly related to its relative concentration in the medium and was not significantly affected by the nature of the diluent fatty acid chosen. Constant relative proportions were recovered in triacylglycerols and in intermediates in each instance. The amount of palmitic acid esterified to each of the positions of the triacyl-sn-glycerols was linearly dependent on the relative proportion in the medium but the nature of the relationship was markedly influenced by which fatty acid was present. When stearic acid was present, simple relationships were found over the whole range tested. When either myristic acid, oleic acid or linoleic acid was present, abrupt changes in the manner of esterification of palmitic acid were observed in position sn-1 when the relative concentrations of palmitic acid and the diluent reached critical values, which differed with each fatty acid. In position sn-2 when oleic acid or linoleic acid was present, a similar change was observed, and in position sn-3 it was obtained with myristic acid as diluent. The results are discussed in terms of changes in the relative affinities of the acyltransferases for palmitic acid. Palmitic acid was esterified into various molecular species in proportions that indicated acylation with non-correlative specificity at higher relative concentrations but not at lower.



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