Polyunsaturated Fatty Acid Ethyl Esters Research Articles

Efficacy and safety of omega-3-acid ethyl acetate 90 capsules in severe hypertriglyceridemia: A randomized, controlled, multicenter study.

Omega-3-acid ethyl acetate 90 capsules (containing 465 mg of eicosapentaenoic acid and 375 mg docosahexaenoic acid) is composed of highly purified omega-3 polyunsaturated fatty acid (PUFA) ethyl esters, whose lipid-lowering effect for severe hypertriglyceridemia (HTG) treatment is unclear. This study aimed to evaluate the efficacy and safety of omega-3-acid ethyl acetate 90 capsules in patients with severe HTG. In this randomized, double-blind, placebo-controlled, multicenter study, 239 patients with severe HTG were enrolled and randomized (1:1) into omega-3 group (N = 122) and placebo group (N = 117) to receive 12-week corresponding treatments. Lipid-related indexes were obtained at treatment initiation (W0), 4 weeks (W4), W8, and W12 after treatment. Adverse events and adverse drug reactions were recorded. Triacylglycerols (TAG), total cholesterol (TC), non-high-density lipoprotein cholesterol (non-HDL-C), very-low-density lipoprotein cholesterol (VLDL-C), and apolipoprotein C-III (Apo C-III) at W4, W8, and W12 were decreased in the omega-3 group versus the placebo group (all p < 0.05). Moreover, the percentage changes of TAG, TC, non-HDL-C, and VLDL-C from W0 to W4, W8, and W12, and the percentage change of Apo C-III from W0 to W4 and W8, were more obvious in the omega-3 group compared with the placebo group (all p < 0.05). However, no difference was observed in the percentage changes of HDL-C, low-density lipoprotein cholesterol (LDL-C), and LDL-C/HDL-C ratio during follow-up between groups (all p > 0.05). Additionally, there was no discrepancy in adverse events and adverse drug reactions between groups (all p > 0.05). Omega-3-acid ethyl acetate 90 capsules exhibit satisfied lipid-lowering effect with tolerable safety profile in patients with severe HTG.

The Biorefinery of the Marine Microalga Crypthecodinium cohnii as a Strategy to Valorize Microalgal Oil Fractions

Chrypthecodinium cohnii lipids have been almost exclusively used as a source of Docosahexaenoic acid (DHA). Such an approach wastes the remaining microalgal lipid fraction. The present work presents a novel process to produce C. cohnii biomass, using low-cost industrial by-products (raw glycerol and corn steep liquor), in a 7L-bioreactor, under fed-batch regime. At the end of the fermentation, the biomass concentration reached 9.2 g/L and the lipid content and lipid average productivity attained 28.0% (w/w dry cell weight) and 13.6 mg/L h, respectively. Afterwards the microalgal biomass underwent a saponification reaction to produce fatty acid (FA) soaps, which were further converted into FA ethyl ester (FA EE). C. cohnii FA EE mixture was then fractionated, using the urea complexation method at different temperatures, in order to obtain a polyunsaturated fatty acid ethyl ester (PUFA EE) rich fraction, that could be used for food/pharmaceutical/cosmetic purposes, and a saturated fatty acid ethyl ester (SAT EE) rich fraction, which could be used as biodiesel. The temperature that promoted the best separation between PUFA and SAT EE, was −18 °C, resulting in a liquid fraction with 91.6% (w/w) DHA, and a solid phase with 88.2% of SAT and monounsaturated fatty acid ethyl ester (MONOUNSAT), which could be used for biodiesel purposes after a hydrogenation step.

Treatment of Chinese Patients with Hypertriglyceridemia with a Pharmaceutical-Grade Preparation of Highly Purified Omega-3 Polyunsaturated Fatty Acid Ethyl Esters: Main Results of a Randomized, Double-Blind, Controlled Trial

IntroductionThe lipid-modifying potential of omega-3 polyunsaturated fatty acids in Chinese patients is under-researched. We conducted a multicenter, randomized, placebo-controlled, double-blind, parallel-group study of twice-daily treatment with OMACOR (OM3EE), a prescription-only formulation of highly purified ethyl esters of omega-3 polyunsaturated fatty acids in Chinese adult patients (≥18 years) who had elevated baseline fasting serum triglycerides (TG).MethodsPatients were stratified according to the severity of their hypertriglyceridemia (severe HTG, with baseline TG ≥500 and <1000 mg/dL or moderate HTG, with baseline TG >200 and <500 mg/dL) or use of statins. Patients randomized to OM3EE therapy received 2 g/day for 4 weeks, then 4 g/day for 8 weeks. The primary efficacy endpoint was the percentage change in fasting serum TG between baseline and the end of treatment in patients with severe HTG. The study was concluded after a planned interim analysis demonstrated a significant TG-lowering effect of OM3EE in that contingent (p=0.0019).ResultsThe mean TG end-of-treatment effect of OM3EE was –29.46% (standard deviation 40.60%) in the severe HTG contingent compared with +0.26% (standard deviation 54.68%) in the placebo group. Corresponding changes were –12.12% and –23.25% in the moderate HTG and combination cohorts (vs +55.45% and +6.24% in relevant placebo groups). A dose-dependent reduction in TG was evident in all patient contingents. Safety and tolerability of OM3EE were in line with previous experience.DiscussionThese data indicate that OMACOR therapy at a dose of 2–4 g/day is an effective treatment for Chinese patients with raised TG levels and is well tolerated.

N-3 Polyunsaturated fatty acid ethyl esters decrease the invasion, but not the proliferation, of human colorectal cancer cells via a PI3K-dependent mechanism in vitro

N-3 polyunsaturated fatty acid (PUFA) ethyl esters have been approved by the FDA for the treatment of dyslipidemia and are promising cancer therapeutics. The study objectives were to determine if and how n-3 PUFA ethyl esters affected the proliferation and invasion of colorectal cancer cells. SW620 and HCT-116 parental and HCT-116 mutant cells isogenic for constitutively active PI3K were treated with free or ethyl esterified n-3 PUFAs and counted 72 h later. Cells were also administered n-3 PUFA ethyl esters to determine if these compounds decreased invasion through Boyden chambers and PI3K activity via western blot analysis of phosphorylated Akt. Free and n-3 PUFA ethyl esters decreased the proliferation of all cell lines. The invasion and Akt phosphorylation of both parental cell lines was decreased following treatment but this did not occur in mutant cells. The ability of n-3 PUFA ethyl esters to decrease proliferation and invasion in vitro indicates these compounds may be effective in vivo.

Azacarbazole n-3 and n-6 polyunsaturated fatty acids ethyl esters nanoemulsion with enhanced efficacy against Plasmodium falciparum

Alternative therapies are necessary for the treatment of malaria due to emerging drug resistance. However, many promising antimalarial compounds have poor water solubility and suffer from the lack of suitable delivery systems, which seriously limits their activity. To address this problem, we synthesized a series of azacarbazoles that were evaluated for antimalarial activity against D10 (chloroquine-sensitive) and W2 (chloroquine-resistant) strains of P. falciparum. The most active compound, 9H-3-azacarbazole (3), was encapsulated in a novel o/w nanoemulsion consisting of ethyl esters of polyunsaturated fatty acids n-3 and n-6 obtained from flax oil as the oil phase, Smix (Tween 80 and Transcutol HP) and water. This formulation was further analyzed using transmission electron microscopy, dynamic light scattering and in vitro and in vivo studies. It was shown that droplets of the 3-loaded nanosystem were spherical, with satisfactory stability, without cytotoxicity towards fibroblasts and intestinal cell lines at concentrations corresponding to twice the IC50 for P. falciparum. Moreover, the nanoemulsion with this type of oil phase was internalized by Caco-2 cells. Additionally, pharmacokinetics demonstrated rapid absorption of compound 3 (tmax = 5.0 min) after intragastric administration of 3-encapsulated nanoemulsion at a dose of 0.02 mg/kg in mice, with penetration of compound 3 to deep compartments. The 3-encapsulated nanoemulsion was found to be 2.8 and 4.2 times more effective in inhibiting the D10 and W2 strains of the parasite, respectively, compared to non-encapsulated 3. Our findings support a role for novel o/w nanoemulsions as delivery vehicles for antimalarial drugs.

A novel clean process for the combined production of fatty acid ethyl esters (FAEEs) and the ethyl ester of polyunsaturated fatty acids (PUFAs) from microalgae oils

Although the methanolysis of microalgae oil for biodiesel preparation was studied previously, the ethanolysis for the combined production of fatty acid ethyl esters (FAEEs, also can be used as biodiesel) and the ethyl esters of PUFAs (an important health-care product) rarely reported. In this work, a novel two-step process, hydrolysis of microalgae oil followed by lipase-mediated ethanolysis, was developed for the synthesis of FAEEs and the ethyl ester of PUFAs. The hydrolysis was firstly performed and the generated free fatty acids was collected and further used for FAEEs synthesis catalyzed by lipase. For lipase-catalyzed ethanolysis, the adding strategy of methanol, molecular sieve dosage, lipase dosage and temperature had significant influence on the FAEE yield. Under the optimized conditions, a FAEE yield of 97% could be obtained. Novozym435 was found to be equally effective for catalyzing the ethanolysis of conventional free fatty acids and PUFAs. The combined effects of multiple factors on the ethanolysis was further studied using Response Surface Methodology (RSM). Validation statistical analysis suggested that the negative correlation existed between FAEE yield and the water content. This work provided a novel strategy to produce FAEEs and the ethyl esters of PUFA effectively with microalgae oil as the substrate.

Enzymatic ethanolysis of fish oil for selective concentration of polyunsaturated fatty acids (PUFAs) with flexible production of corresponding glycerides and ethyl esters

AbstractBACKGROUNDProducts with high concentrations of polyunsaturated fatty acids (PUFAs) are now in high demand for health care and medicine. In this work, a novel lipase‐catalyzed ethanolysis of low‐grade fish oil was developed with combined use of two commercial free and immobilized lipases (triacylglycerol acylhydrolase, EC 3.1.1.3), namely Novozyme NS81006 and 435, to flexibly produce fatty acid ethyl esters (FAEEs) and concentrated PUFAs.RESULTSIn a first step, most of the fatty acid glycerides (FAGCs) were converted to ethyl esters with conversion rate of 70–80% but only a minor part of docosahexaenoic fatty acids (DHAs) was converted (&lt;20%). Using molecular distillation to evaporate FAEEs, the content of PUFAs in the resulting heavy phase, primarily as glycerides and secondarily as ethyl esters, increased from ∼18% of crude fish oil to 34%. A second ethanolysis step under the catalysis of Novozyme 435 was used to further convert the residual FAGCs, especially DHA glyceride, to ethyl esters with final conversion rates of 80–100%. PUFAs content was further enhanced to 41% in the form of PUFA ethyl esters after a second‐stage moleulcar distillation.CONCLUSIONSThis two‐step process combined the merits of free and immobilized lipases for ethanolysis of fish oil, achieving high conversion of PUFAs to corresponding ethyl esters with significant improvement of catalyst reusability in the second step. This process also provides flexible production of enriched PUFAs in the forms of glycerides or ethyl esters from low‐grade fish oil feedstocks. © 2018 Society of Chemical Industry

Stearidonic Acid Concentration by Urea Complexation from Echium Oil.

Concentration of polyunsaturated fatty acids ethyl esters (FAEE) by urea complexation from Echium oil was studied. Different variables involved in the process were investigated: amount and particle size of urea, solvent volume and ratio (hexane/ethanol), load of FAEE and reaction time. Hence, the main goal was to optimize SDA concentration (%) and yield (%) of stearidonic acid (SDA, 18:4 ω-3) and other bioactive FAEE. Similar behaviors were observed in fractionation between α-linolenic (ALA)-linoleic (LA), and γ-linolenic (GLA)-stearidonic (SDA) acids, attributed to similarities on their chemical structures, due to the position of the double bonds. At laboratory scale, the optimal conditions were 3 g urea (powder), 3.6 mL of hexane, 0.54 mL of ethanol and 800 mg of FAEE, during 20 h at 25°C. A scaling-up at pilot plant was carried out twice, obtaining more than 100 g of a final product, with ~29% SDA concentration and ~78% yield. Besides, after two washings with water, ethyl carbamates (urethanes) were not detected in the final product. Thus, a mixture of FAEE with about 85% of bioactive fatty acids with anti-inflammatory properties was obtained, which can be a high added-value product with great potential for the synthesis of functional lipids and nutraceuticals.

Isolation of Non‐methylene Interrupted or Acetylenic Fatty Acids from Seed Oils Using Semi‐preparative Supercritical Chromatography

AbstractPreparative scale supercritical fluid chromatography was used for isolating and purifying uncommon non‐methylene interrupted or acetylenic polyunsaturated fatty acids ethyl esters from seed oils. Fractionation of Biota orientalis seed oil ethyl esters was performed by supercritical fluid chromatography to obtain juniperonic acid [(5Z,11Z,14Z,17Z)‐eicosa‐5,11,14,17‐tetraenoic acid], a non‐methylene interrupted polyunsaturated fatty acid. Fractionation of sandalwood seed oil ethyl esters yielded ximenynic acid [(E)‐octadec‐11‐en‐9‐ynoic acid], an acetylenic polyunsaturated fatty acid. The effects of CO2 flow rate, column stationary phase and particle size were explored to optimize ximenynic and juniperonic ethyl ester recovery and purity from ethyl ester mixtures using online UV/Vis detection. Particle size, followed by the stationary phase, were found to be the most important parameters to achieving good separation. Under optimized conditions, ximenynic and juniperonic ethyl ester purities greater than 99 and 95%, respectively, were achieved in a one step process without co‐solvent. The isolation and recovery of juniperonic acid from biota seed oil free fatty acids was also attempted. Using free fatty acids as the feed material, the non‐methylene interrupted polyunsaturated sciadonic acid was also able to be separated from other compounds including juniperonic acid under some conditions, and gave an increase in concentration of more than 17 times.

Solid-phase microextraction may catalize hydrogenation when using hydrogen as carrier in gas chromatography

When hydrogen is used as carrier gas, carbon-carbon double bonds may be hydrogenated in the hot gas chromatograph (GC) injector if introduced by solid-phase microextraction (SPME). SPME fibers coated with polydimethylsiloxane (PDMS)/carboxen/divinylbenzene (DVB), PDMS/carboxen, polyacrylate, PDMS/DVB and PDMS on fused silica, stableflex or metal alloy core have been tested with fatty acid methyl esters (FAMEs) from olive oil. Using coatings containing DVB, hydrogenation took place with high conversion rates (82.0–92.9%) independently of the core material. With all fibers having a metal core, hydrogenation was observed to a certain extent (27.4–85.3%). PDMS, PDMS/carboxen and polyacrylate coated fibers with a fused silica or stableflex core resulted in negligible hydrogenation (0.2–2.5%). The occurrence of hydrogenation was confirmed also with other substances containing carbon-carbon double bonds (n-alkenes, alkenoic acids, mono- and polyunsaturated fatty acid methyl and ethyl esters).

Production of Omega-3 Fatty Acid Ethyl Esters from Menhaden Oil Using Proteus vulgaris Lipase-Mediated One-Step Transesterification and Urea Complexation.

An organic solvent-stable lipase from Proteus vulgaris K80 was used to produce the omega-3 polyunsaturated fatty acid ethyl esters (ω-3 PUFA EEs). First, the lyophilized recombinant lipase K80 (LyoK80) was used to perform the transesterification reaction of menhaden oil and ethanol. LyoK80 produced the ω-3 PUFA EEs with a conversion yield of 82% in the presence of 20% water content via a three-step ethanol-feeding process; however, in a non-aqueous condition, LyoK80 produced only a slight amount of the ω-3 PUFA EEs. To enhance its reaction properties, the lipase K80 was immobilized on a hydrophobic bead to derive ImmK80; the biochemical properties and substrate specificity of ImmK80 are similar to those of LyoK80. ImmK80 was then used to produce ω-3 PUFA EEs in accordance with the same transesterification reaction. Unlike LyoK80, ImmK80 achieved a high ω-3 PUFA EE conversion yield of 86% under a non-aqueous system via a one-step ethanol-feeding reaction. The ω-3 PUFA EEs were purified up to 92% using a urea complexation method.

Extraction of EPA/DHA from 18/12EE Fish Oil Using AgNO3(aq): Composition, Yield, and Effects of Solvent Addition on Interfacial Tension and Flow Pattern in Mini-Fluidic Systems

Solvent extraction of Omega-3 polyunsaturated fatty acids (PUFA) ethyl esters (Et) from 18/12EE fish oil was performed with an aqueous silver nitrate solution in a mini-fluidic reactor framework. The resulting extraction was compared within conventional stirred-tank reactors, with practical extraction yields of EPA-Et and DHA-Et approaching 60 to 70 wt %. Equilibrium was reached in less than 36 s at 10 °C, despite stratified flow being observed rather than previously reported slug-flow profiles in idealized fluid pairs at these scales. The deviation in flow pattern was attributed to a measured order of magnitude reduction in the interfacial tension between fish oils and AgNO3 solution relative to idealized solvent mixtures using hexane/heptane as a carrier for purified EPA/DHA. The impact of solvent addition to fish oils on interfacial tension with silver nitrate solutions was subsequently explored through spinning drop tensiometry, suggesting that the heterogeneous nature of raw fish oils will yield sign...

Two New Antifungal Polyunsaturated Fatty Acid Ethyl Esters from the Red Alga Laurencia okamurai

Two new polyunsaturated fatty acid ethyl esters, (9Z,12Z,15Z,18Z,21Z)-ethyl tetracosa-9,12,15,18,21-pentaenoate (1) and (10Z,13Z)-ethyl nonadeca-10,13-dienoate (2), were isolated from a re-collection of the red alga Laurencia okamurai Yamada, together with three known analogues, (9Z,12Z)-ethyl nonadeca-9,12-dienoate (3), (Z)-ethyl octadec-13-enoate (4), and (Z)-ethyl hexadec-11-enoate (5). Their structures were elucidated on the basis of detailed spectroscopic analysis, including IR, HR-EI-MS, and 1D and 2D NMR. In in vitro bioassays, all the isolates were evaluated for their antifungal activity against four fungi, including Candida glabrata (537), Trichophyton rubrum (Cmccftla), Cryptococcus neoformans (32609), and Aspergillus fumigatus (07544).

Magnetoliposomes loaded with poly-unsaturated fatty acids as novel theranostic anti-inflammatory formulations.

We describe the preparation, physico-chemical characterization and anti-inflammatory properties of liposomes containing the superparamagnetic nanoparticle Nanotex, the fluorescent dye Rhodamine-100 and omega-3 polyunsaturated fatty acid ethyl ester (ω-3 PUFA-EE), as theranostic anti-inflammatory agents. Liposomes were prepared after drying chloroform suspensions of egg phosphatidylcholine, hydration of the lipid film with aqueous phases containing or not Nanotex, Rhodamine-100 dye or ω-3 PUFA-EE, and eleven extrusion steps through nanometric membrane filters. This resulted in uniform preparations of liposomes of approximately 200 nm diameter. Extraliposomal contents were removed from the preparation by gel filtration chromatography. High Resolution Magic Angle Spinning 1H NMR Spectroscopy of the liposomal preparations containing ω-3 PUFA-EE revealed well resolved 1H resonances from highly mobile ω-3 PUFA-EE, suggesting the formation of very small (ca. 10 nm) ω-3 PUFA-EE nanogoticules, tumbling fast in the NMR timescale. Chloroform extraction of the liposomal preparations revealed additionally the incorporation of ω-3 PUFA-EE within the membrane domain. Water diffusion weighted spectra, indicated that the goticules of ω-3 PUFA-EE or its insertion in the membrane did not affect the average translational diffusion coefficient of water, suggesting an intraliposomal localization, that was confirmed by ultrafiltration. The therapeutic efficacy of these preparations was tested in two different models of inflammatory disease as inflammatory colitis or the inflammatory component associated to glioma development. Results indicate that the magnetoliposomes loaded with ω-3 PUFA-EE allowed MRI visualization in vivo and improved the outcome of inflammatory disease in both animal models, decreasing significantly colonic inflammation and delaying, or even reversing, glioma development. Together, our results indicate that magnetoliposomes loaded with ω-3 PUFA-EE may become useful anti-inflammatory agents for image guided drug delivery.

Cardiovascular risk and lipid management beyond statin therapy: the potential role of omega–3 polyunsaturated fatty acid ethyl esters

Although statins are widely effective at reducing LDL cholesterol (LDL-C) and clinical cardiovascular events, the risk of cardiovascular disease remains high in certain patient subgroups, despite effective LDL-C reduction. This is typically the case in those with Type 2 diabetes. This ‘residual risk’ is partly attributable to lipid abnormalities distinct from LDL-C, such as elevated triglyceride (TG)-rich lipoproteins and low levels of HDL cholesterol (HDL-C). Clinical trials demonstrate that use of other lipid-modifying therapies in combination with statins can further improve lipid profiles: inhibitors of cholesterol and bile acid uptake mainly affect LDL-C, while niacin, fibrates and ω-3 polyunsaturated fatty acid ethyl esters target other plasma lipids, particularly TG and HDL-C. In current practice, patients with higher TGs and lower HDL-C appear to have the greatest potential to benefit from use of additional medications on the background of statin therapy.

Semi-preparative supercritical chromatography scale plant for polyunsaturated fatty acids purification

A one step supercritical fluid chromatography process has been developed using a semi-preparative supercritical fluid chromatography scale plant designed and built in-house, for isolation and purification of polyunsaturated fatty acid ethyl esters from different origins (fish and algae). A wide range of experimental conditions (pressure, temperature, sample load, co-solvent rate and CO2 flow rate); columns (stationary phase and particle size); and UV/vis detectors have been investigated to optimise the isolation and purification of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from an algae oil rich in EPA, and a fish oil rich in EPA and DHA. The particle size, followed by the stationary phase, sample loading, temperature/pressure and feed oil composition, were found to be the most important parameters for achieving separation. Under optimised conditions, EPA at greater than 95% purity from both oils and DHA at greater than 80% purity from fish oil was obtained in a single pass and without co-solvent.

Statins and beyond: Concurrent strategies for prevention of cardiovascular disease in patients with type 2 diabetes

Diabetes is a significant risk factor for the development of cardiovascular disease (CVD), particularly in the presence of high blood pressure, poor glycaemic control and high total cholesterol. While efforts to control blood pressure or blood glucose beyond levels considered 'normal' in patients with diabetes have not produced the expected reduction in CVD, treatment with statins to reduce levels of low-density lipoprotein cholesterol (LDL-C) has been much more successful. However, many patients with diabetes who receive statins (even at high doses) remain at significant residual risk of CVD due to the presence of atherogenic dyslipidaemia. Markers of persisting risk include low levels of high-density lipoprotein cholesterol (HDL-C), high levels of triglycerides (TG) and LDL-C levels above target despite high-dose statin therapy. Combining statins with drugs that target HDL-C and TG, such as fibrates, niacin and omega-3 polyunsaturated fatty acid (PUFA) ethyl esters, may offer further protection from CVD in patients with diabetes.

Bioequivalence of two omega‐3 fatty acid ethyl ester formulations: a case of clinical pharmacology of dietary supplements

• Omega-3 fatty acids are dietary components, present in the body with variable blood concentrations. • Bioavailability evaluations of ethyl ester preparations are hampered by the difficulty in achieving similar concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the preparations being compared. This may require questionable corrections for baseline concentrations. • If repeated doses are given, this may lead to errors because of variable dietary fish intake. If a single dose is selected, this needs to be large, since omega-3 LC-PUFA are present in many compartments. • We selected subjects with uniform omega-3 background concentrations, to obtain comparable results at the end of treatment. • Testing bioequivalence of two formulations with different EPA : DHA ratios led to single dose intakes of 12 g, which were well tolerated. • In spite of clear differences in EPA : DHA ratios between the two preparations, plasma ratios did not differ and bioequivalence could be well ascertained. To evaluate the bioequivalence of two omega-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA) ethyl ester preparations, previously shown not to be bioequivalent in healthy subjects, with the objective of providing a guideline for future work in this area. A randomized double-blind crossover protocol was chosen. Volunteers with the lowest blood concentrations of n-3 LC-PUFA were selected. They received the ethyl esters in a single high dose (12 g) and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) blood concentrations were analyzed after fingerprick collection at intervals up to 24 h. Differently from a prior study, the pharmacokinetic analysis indicated a satisfactory bioequivalence: for the AUC(0,24 h) 90% CI of the ratio between the two formulations were in the range for bioequivalence (for EPA 0.98, 1.04 and for DHA 0.99, 1.04) and the same was true for C(max) and t(max) (90% CI were 0.95, 1.14 and 1.10, 1.25 for EPA and 0.88, 1.02 and 0.84, 1.24 for DHA). This study shows that, in order to obtain reliable bioequivalence data of products present in the daily diet, certain conditions should be met. Subjects should have low, homogeneous baseline concentrations and not be exposed to food items containing the product under evaluation, e.g. fish. Finally, as in the case of omega-3 fatty acids, selected doses should be high, eventually with appropriate conditions of intake.

A process for the synthesis of PUFA-enriched triglycerides from high-acid crude fish oil

This paper reports a research interest, that aims to establish a feasible industrial process, for the enzymatic production of glycerides with highly concentrated n-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid), from high-acid crude fish oils. The process covers enzymatic deacidification of crude fish oil, alkaline-based synthesis of polyunsaturated fatty acids ethyl esters, concentration of polyunsaturated fatty acids ethyl esters, and enzyme catalyzed synthesis of polyunsaturated fatty acids glycerides. Commercial available immobilized lipase, Novozym 435, was used as the catalyst. The synthesized glycerides contained 5.5% of eicosapentaenoic acid and 74.6% of docosahexaenoic acid, which was 1.21 and 2.71 times more than that in the original fish oil, respectively. The application of the designed process was successfully proved by a 100-fold scale-up reaction.

Extraction and Enrichment of n-3 Polyunsaturated Fatty Acids and Ethyl Esters through Reversible π–π Complexation with Aromatic Rings Containing Ionic Liquids

The present study investigated the potentials of ionic liquids (ILs) containing aromatic rings in extracting and enriching n-3 polyunsaturated compounds. The relationship between extraction efficiency, selectivity, and structure of ILs was studied and elucidated. Ionic liquids containing aromatic rings such as the N,N'-dialkylimidazolium and N-alkylpyridinium are found to selectively extract and enrich n-3 polyunsaturated compounds. The IL extraction process reached equilibrium relatively quickly (<30 min), and the extraction efficiency can be further enhanced by increasing the volume ratio of IL to solvent, addition of silver tetrafluoroborate, and usage of double bond containing solvents such as 1-hexene as stripping solvent. At optimal conditions, 1-butyl-3-methylimidazolium hexafluorophosphate [bmim]PF(6) and 1-butyl-3-methylpyridinium dicyanamide [BuMePyr]DCN had increased extraction capabilities of n-3 polyunsaturated fatty acids (PUFA) (16.19%) and n-3 polyunsaturated fatty acid ethyl esters (PUFAEE) (144.54%), respectively. Multiple-step reverse extraction whereby n-3 PUFAs were first enriched through IL/hexane extraction followed by addition of fresh hexane repeatedly up to three times to the IL phase to desorb the saturated FAs resulted in a higher purity of n-3 PUFAs. Following this reverse extraction operation, the purity of n-3 PUFA and n-3 PUFAEE in the IL phase increased from the initial 15.88 to 38% (step 1) and further to 45% (step 3) and from the initial 72.56 to 82% (step 1) and further to 89% (step 3), respectively. The results from this study strongly suggested the correlation of n-3 PUFA extraction with aromatic/delocalized cation structure of ILs, which provides the basis for future research in designing novel ILs task-specified for efficient long-chain PUFA concentration.