Oil Fatty Acid Ethyl Esters Research Articles

Positional distribution of docosahexaenoic acid in triacyl-sn-glycerols of rotifers Brachionus plicatilis enriched with fish oil fatty acid ethyl esters

Positional distribution of docosahexaenoic acid in triacyl-sn-glycerols of rotifers Brachionus plicatilis enriched with fish oil fatty acid ethyl esters

Thermodynamic Modeling and Process Optimization of Supercritical Fluid Fractionation of Fish Oil Fatty Acid Ethyl Esters

Rigorous thermodynamic modeling, simulation, and optimization of the supercritical fractionation of EPA and DHA esters is presented. These valuable products are obtained from complex mixtures of fish oil fatty acid alkyl esters by high-pressure fractionation with supercritical carbon dioxide. A group contribution equation of state (GC-EOS) that provides reliable phase equilibrium and solubility predictions is used to support the process simulation. A correlation has been developed for the estimation of a thermodynamic model parameter: the fish oil esters hard-sphere diameter. The capability of the group contribution equation of state is confirmed by a detailed comparison of predictions with experimental data. Rigorous simulation models for process units have been formulated within a nonlinear optimization model to maximize EPA and DHA esters recovery and purity from several natural fish oil mixtures with supercritical extraction.

Phase equilibria of long-chain polyunsaturated fish oil fatty acid ethyl esters and carbon dioxide, ethane, or ethylene at reduced gas temperatures of 1.03 and 1.13

Phase equilibria of a mixture of long-chain polyunsaturated fish oil fatty acid ethyl esters (FAEEs) with carbon dioxide were measured at 313.2 and 343.2 K, with ethane at 314.0 and 344.6 K, and with ethylene at 290.9 and 318.6 K. The temperatures correspond to reduced gas temperatures of approximately 1.03 and 1.13. The experimental pressures range from 1.6 to 25 MPa. The FAEE mixture is rich in eicosapentaenoic acid ethyl ester (EPA, 52.5 wt.%), and docosahexaenoic acid ethyl ester (DHA, 36.1 wt.%), and a total of 10 components were identified. The experimental temperatures, pressures, solubilities, mass fractions, and calculated equilibrium ratios are reported in tables and graphs. The mass fractions and the equilibrium ratios are reported on a solvent-free basis.

Phase Equilibria of Urea-Fractionated Fish Oil Fatty Acid Ethyl Esters and Supercritical Carbon Dioxide

Measurements of phase equilibria of urea-fractionated fish oil fatty acid ethyl esters (FAEEs) in supercritical carbon dioxide were performed at pressures from 8 to 26 MPa and temperatures of 313.2 and 343.2 K. Experimental temperatures, pressures, and mass fractions are reported in tubular form. The equilibrium ratios of the esters depend strongly on the system pressure and temperature, and a comparison with previous equilibrium measurements on the fatty acid ethyl ester mixture before the urea fractionation shows that they also depend on the composition of the ester mixture. The data show that high selectivity and low solubility are obtained at low operating pressures, while at high operating pressures the selectivity is low but the solubility is high. Twenty-nine components corresponding to more than 90% of the natural mixture are identified. The three polyunsaturated FAEEs, C 18:4n3 , C 20:5n3 , and C 22:6n3 , correspond to more than 80% of the urea-fractionated mixture

Partition Coefficients and Solubility of Urea‐Fractionated Fatty Acid Ethyl Esters from Fish Oil in Supercritical CO2

AbstractSolubilities and K‐values of urea‐fractionated fish oil fatty acid ethyl esters, prepared from sandeel oil, have been measured in supercritical carbon dioxide experimentally. The measurements were performed at the temperatures of 313.2 and 343.2 K in the pressure range of 8 to 26 MPa. Experimental temperatures, pressures, and densities of the equilibrium phases are tabulated. The K‐values of the ethyl esters of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and oleic acid of the urea‐fractionated mixture are compared with previously published experimental binary and multicomponent data on the same mixture before performing the urea‐fractionation. K‐value data of this type are essential to conceive proper equipment design for separation of the various polyunsaturated ω‐3 fatty acids present in fish oil as esters.

Flame ionization detector responses to ethyl esters of sand eel (Ammodytes lancea) fish oil compared for different gas and supercritical fluid chromatographic systems

A fish oil fatty acid ethyl ester mixture derived from the sand eel (Ammodytes lancea) has been analysed using various capillary gas chromatography (GC) and supercritical fluid chromatography (SFC) methods and 39 components including cholesterol have been identified. The results of the analytical SFC and GC experiments are compared showing a good reproducibility within methods and a fair agreement between methods. The advantages and disadvantages of the employment of manual and autosampler split injection, splitless injection, and cold on-column injection in GC as well as the use of polar and non-polar columns in GC and SFC are discussed.

Phase equilibria of fish oil fatty acid ethyl esters and sub- and supercritical CO 2

Measurements of phase equilibria of fish oil fatty acid ethyl esters in sub- and supercritical carbon dioxide were performed at pressures from 2 to 22 MPa at the temperatures 283.2, 313.2, and 343.2 K. Experimental temperatures, pressures, mass fractions, mole fractions, equilibrium ratios, and densities are reported. The K-values of the esters depend strongly on the system pressure and the number of carbon atoms and have a weaker dependence on the degree of unsaturation and position of the double bonds. The data show that the selectivity is high and the solubility is low at low operating pressure, while at high operating pressure the selectivity is low but the solubility is high. More than 95% of the natural mixture was identified.

Solubility of fish oil fatty acid ethyl esters in suband supercritical carbon dioxide

Mutual solubilities and K‐values of fish oil fatty acid ethyl esters, prepared from sand launce oil, and sub‐ and supercritical carbon dioxide have been measured in an apparatus originally designed for phase equilibrium, density and gasoil ratio measurements of reservoir fluids. The measurements were performed at pressures from 2 to 22 MPa at temperatures of 283.2, 313.2 and 343.2°K. Experimental temperatures, pressures, solubilities, K‐values and densities are reported. The K‐values of ethyl myristate, palmitate, oleate, eicosapentaenoate and docosahexaenoate are compared with published experimental binary and/or multicomponent data. Because both vapor and liquid solubilities are reported, such data are applicable in the design of supercritical extraction plants.

Fractionation of menhaden oil ethyl esters using supercritical fluid CO2

AbstractSupercritical fluid CO2 was used to fractionate menhaden oil fatty acid ethyl esters to obtain concentrates of the esters of allcis‐5,8,11,14,17‐eicosapentaenoic acid (EPA) and allcis‐4,7,10,13,16,19‐docosahexaenoic acid (DHA). Separation of the ethyl esters was found to occur primarily by carbon number, thus limiting the degree to which the ethyl esters of EPA and DHA could be concentrated. Urea fractionation of whole esters in order to remove saturates, monoenes and dienes prior to fractionation with supercritical fluid CO2 resulted in concentrates of EPA and DHA in purities exceeding 90%. Several criteria are given for the selection of crude oils in order to maximize both purity and yield of concentrates.

Heat Cyclization of Eleostearate with Sulfur

Tung oil fatty acid ethyl ester, which contained eleostearate in 80 per cent, was diluted with ethyl myristate and heated to cyclize with 0.2wt% sulfur at 160, 220 and 290°C. The yield of cyclic monomer was very higher than that of the cyclization without sulfur. Then thermal treatment of tung oil fatty ester, ethyl oleate and ethyl elaidate with sulfur were analysed by ESR respectively to examine the effect acid ethyl of sulfur. It was found at least that sulfur catalyzed random cis-trans isomerization, i.e. in cyclization trans double bond between 11 and 12 carban of eleostearate was isomerized to cis form remarkably by sulfur.

Quantitative analysis of cyclopentadiene compounds

Abstract and SummaryA quantitative color reaction of cyclopentadiene was examined when cyclopentadiene was contained in a mixture of benzene, 1,3‐cyclohexadiene, cyclohexene, cyclohexane, cyclopentene, or cyclopentane. It was found that cyclopentadiene could be determined in the following manner. A sample was weighed to 1.38 x 10‐5 mole in a test tube, while a mixture of 10 ml ethyl alcohol plus 4 ml sulfuric acid was cooled in an ice bath. The mixture was poured into the test tube and the tube was heated in a water bath at 95 C for 30 sec followed by immediate cooling. Then the absorbance at 580 nm was measured and the content of cyclopentadiene was calculated with a calibration curve. The color reaction was tested with ethyl linoleate cyclic monomer (11 cm), ethyl linolenate cyclic monomer (mem), and photoisomerized tung oil fatty acid ethyl ester cyclic monomer (βcm), which were prepared from each purified fatty acid or from photo‐isomerized tung oil by cyclization with sodium hydroxide. It was found that cyclopentadiene compounds were formed from ethyl linolenate, but not from ethyl linoleate or from β‐eleostearate, which was a main component of photo‐isomerized tung oil.

Studies on Nutritive Value of Synthesized Fatty Acid

Mixed fatty acids synthesized by air oxidation of paraffin were obtained from the Soviet Union. The mixed fatty acids were fractionated to C5-6, C7-9, C14-16 and C17-20 fractions by vacuum distillation, molecular sieve and the other methods, and these fractions were esterified with ethanol by usual method. Then, the nutritive value of the each ester was compared with salad oil fatty acid ethyl ester prepared from commercial salad oil by feedings in Wister strain rats. The rats were fed 10% of each ester or contralled ester mixed with basal diets. As the results, there was no difference between the weight gain of the sample ethyl esters prepared from synthesized fatty acids and the salad oil fatty acid ethyl ester.

Studies of Structural Changes of Unsaturated Fatty Acid by Heating. II.

Many papers have ever been reported about cyclic monomers (mostly 6-membered ring compounds) formed from unsaturated fatty acids or their triglycerides during thermal treatment or by catalytic cyclization. But, existance of 5-membered ring compounds in such cyclic monomers has not been proved chemically. Therefore qualitative and quantitative condition of the color reaction of cyclopentadiene in a mixture of 1, 3-cyclohexadiene, benzene, cyclohexene, cyclohexane, cyclopentene and cyclopentane, was examined using sulfuric acid and ethyl alcohol in reference to our previous papers. On the other hand, purified ethyl linoleate, ethyl linolenate and photo-isomerized Lung oil were respectively heated to cyclize with sodium hydroxide and ethylene glycol under the condition of 295°C, 15min. in a stainless autoclave, then acidified, esterified and purified by silica gel column, yThe cyclized ethyl linoleate, ethyl linolenate and photo-isomerized tong oil fatty acid ethyl ester were separated by urea adduct and column chromatography obtained ethyl linoleate cyclic monomer (11CM), ethyl linolenate cyclic monomer (1nCM) and photo-isomerized tung oil fatty acid ethyl ester cyclic monomer (βCM) were analyzed by GLC, IR, TLC and the above mentioned color reaction. It was concluded that cyclopentadiene compounds were formed from ethyl linolenate, but not from ethyl linoleate and eleostearic acid, since 1nCM, βCM and 11CM contained 4.1%, 0.08% and 0% of cyclopentadiene compounds respectively.

Alimentary production of gallstones in hamsters. 27. Influence of supplementation of the gallstone producing diet with squalene, cholesterol, certain other sterols, fish oil fatty acid ethyl esters, and modification of the basal diet on gallstone production and levels of cholesterol in serum and liver.

Alimentary production of gallstones in hamsters. 27. Influence of supplementation of the gallstone producing diet with squalene, cholesterol, certain other sterols, fish oil fatty acid ethyl esters, and modification of the basal diet on gallstone production and levels of cholesterol in serum and liver.