Variability of Omega-3/6 Fatty Acid Obtained Through Extraction-Transesterification Processes from Phaeodactylum tricornutum.

The effect of direct transesterification methods on the omega-3/6 composition of extracts from Phaeodactylum tricornutum was studied. The aim of this work was to identify an extraction method which allowed to obtain the most suitable profile of fatty acids in terms of its potential benefits to health, particularly if further used in the food industry. Seven methods using acids, alkalis, and heterogeneous-catalysts, (namely methods from 1 to 7, abbreviated as M1-M7) were performed to determine α-linolenic (ALA), linoleic (LA), docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids. The composition of fatty acids was in all cases characterized by the major abundance of palmitic (23.95-34.08%), palmitoleic (30.94-35.56%), oleic acids (3.00-7.41%), and EPA (0.5-6.45%). Unsaturated fatty acids extraction yield was higher with a two-step transesterification process (M6, 63.65%). The total fatty acid methyl ester content (FAME) obtained with acid-transesterification (M1) reached about 21% wt, and 60% w/w total lipids. ALA higher relative content (ALA/LA ratio) was obtained when a lipid pre-extraction step was performed prior to acid-catalysis (M4). The transesterification method based on alkali-catalyst (M3, KOH catalyst) led to obtain higher DHA relative contents (DHA/EPA ratio up to 0.11), although its FAME content was 3.75-fold lower than that obtained with acid-transesterification (M1). Overall, this study shows that direct transesterification with alkali-catalyst (M3) improves the determination of PUFA content from the diatom through a more efficient transesterification-based extraction process, and thus allow to assess the value of the biomass more accurately for application in the food industry.

Integrated Multitrophic Aquaculture By-Products with Added Value: The Polychaete Sabella spallanzanii and the Seaweed Chaetomorpha linum as Potential Dietary Ingredients.

Aquaculture expansion is limited by the negative environmental impact of the waste and the need for alternative sources in the diet of reared fish. In this framework, for the first time, the survival rates, biomass gain, and fatty acid profiles of the polychaete Sabella spallanzanii and the macroalga Chaetomorpha linum, reared/cultivated as bioremediators in an integrated multitrophic aquaculture system (IMTA), were evaluated for their potential reuse applications. Results showed that these organisms represent a natural source of omega-3 and omega-6. On account of the overall results and the high biomass obtained as by-products, a preliminary study was performed employing both S. spallanzanii and C. linum as new dietary ingredients to feed different sized Dicentrarchus labrax. Fish survival rate, biomass growth, and specific growth rate were determined resulting in no significant differences between control and treated fishes. Histological analyses showed no alterations of the stomach tunica mucosa and submucosa in treated fishes. The eco-friendly approaches applied in the here-realized IMTA system could guarantee the achievement of sustainable by-products represented by the bioremediators S. spallanzanii and C. linum, as well as their reliability as a natural source of compounds beneficial to fish and human health.

Isolation, Characterization and Biotechnological Potentials of Thraustochytrids from Icelandic Waters.

The following study reports on the first thraustochytrid isolates identified from Iceland. They were collected from three different locations off the northern coast of the country (Location A, Skagaströnd; Location B, Hveravík; and Location C, Eyjafjörður). Using 18S rDNA sequence analysis, isolates from Locations A and B were identified within the Thraustochytrium kinnei species while other isolates within the Sicyoidochytrium minutum species when compared to other known strains. Cells isolated from Locations A ( 2 . 10 ± 0 . 70 g/L) and B ( 1 . 54 ± 0 . 17 g/L) produced more biomass than the ones isolated from Location C ( 0 . 43 ± 0 . 02 g/L). This study offers the first-time examination of the utility of byproducts from fisheries as a nitrogen source in media formulation for thraustochytrids. Experiments showed that isolates produced more biomass (per unit of substrate) when cultured on nitrogen of marine ( 2 . 55 ± 0 . 74 g/L) as compared to of commercial origin (  1 . 06 ± 0 . 57 g/L). Glycerol ( 2 . 43 ± 0 . 56 g/L) was a better carbon source than glucose ( 1 . 84 ± 0 . 57 g/L) in growth studies. Fatty acid (FA) profiles showed that the isolates from Location C (S. minutum) had low ratios of monounsaturated ( 4 . 21 ± 2 . 96 % ) and omega-6 ( 0 . 68 ± 0 . 59 % ) FAs. However, the isolates also had high ratios of docosahexaenoic acid (DHA; 35 . 65 ± 1 . 73 % ) and total omega-3 FAs ( 40 . 39 ± 2 . 39 % ), indicating that they could serve as a source of marine oils for human consumption and in aquaculture feeds. The T. kinnei isolates from Location A could be used in biodiesel production due to their high ratios of monounsaturated ( 18 . 38 ± 6 . 27 % ) long chain ( 57 . 43 ± 8 . 27 % ) FAs.

Tandem Mass Tag Based Quantitative Proteomics of Developing Sea Buckthorn Berries Reveals Candidate Proteins Related to Lipid Metabolism.

Sea buckthorn ( Hippophae L.) is an economically important shrub or small tree distributed in Eurasia. Most of its well-recognized medicinal and nutraceutical products are derived from its berry oil, which is rich in monounsaturated omega-7 (C16:1) fatty acid and polyunsaturated omega-6 (C18:2) and omega-3 (C18:3) fatty acids. In this study, tandem mass tags (TMT)-based quantitative analysis was used to investigate protein profiles of lipid metabolism in sea buckthorn berries harvested 30, 50, and 70 days after flowering. In total, 8626 proteins were identified, 6170 of which were quantified. Deep analysis results for the proteins identified and related pathways revealed initial fatty acid accumulation during whole-berry development. The abundance of most key enzymes involved in fatty acid and triacylglycerol (TAG) biosynthesis peaked at 50 days after flowering, but TAG synthesis through the PDAT (phospholipid: diacylglycerol acyltransferase) pathway mostly occurred early in berry development. In addition, the patterns of proteins involved in lipid metabolism were confirmed by combined quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and parallel reaction monitoring analyses. Our data on the proteomic spectrum of sea buckthorn berries provide a scientific basic for understanding lipid metabolism and related pathways in the developing berries.

Activation of Lipid Mediator Formation Due to Lipoprotein Apheresis.

Lipoprotein apheresis reliably reduces low-density lipoprotein (LDL) cholesterol in patients with atherosclerotic disease and therapy-refractory hypercholesterolemia or elevated lipoprotein (a) (Lp(a)). Besides lowering lipoproteins and triglycerides, apheresis also decreases levels of essential omega-6 and omega-3 polyunsaturated fatty acids (n-6 and n-3 PUFAs) in blood plasma. In contrast, heparin-induced extracorporeal low-density lipoprotein precipitation (HELP) lipid apheresis might increase the formation of potentially pro-inflammatory and pro-thrombotic lipid mediators derived from n-6 and n-3 PUFAs. The study presented here analyzed lipid mediator profiles in the plasma of patients with hyperlipidemia treated by one of three different apheresis methods, either HELP, direct absorption (DA), or membrane filtration (MDF), in a direct pre- and post-apheresis comparison. Using gas chromatography and liquid chromatography tandem mass spectrometry (LC-MS/MS) we were able to analyze fatty acid composition and the formation of lipid mediators called oxylipins. Our data illustrate-particularly in HELP-treated patients-significant decreases of essential omega-6 and omega-3 polyunsaturated fatty acids in blood plasma but significant increases of PUFA-derived lipoxygenase-, as well as cyclooxygenase- and cytochrome P450-derived lipid mediators. Given that n-3 PUFAs in particular are presumed to be cardioprotective and n-3 PUFA-derived lipid mediators might limit inflammatory reactions, these data indicate that n-3 PUFA supplementation in the context of lipid apheresis treatment might have additional benefits through apheresis-triggered protective n-3 PUFA-derived lipid mediators.

Chemical Composition, Characteristics Profiles and Bioactivities of Tunisian Phalaris canariensis Seeds: a Potential Source of ω-6 and ω-9 Fatty Acids.

Seeds oils of Phalaris canariensis extracted by ultrasonication and cold maceration were evaluated for their physical characteristics, total phenol contents, fatty acid and sterol compositions as well as for their antioxidant, antibacterial and acetylcholinesterase activities. The physicochemical properties of ultrasonication and cold maceration oils respectively were: acid values (4.00 and 3.25) mg KOH/g, peroxide values (5.53 and 4.41) meq O2 Kg-1, iodine values (88.83 and 95.17) g/100 g of oil, saponification values (119.21 and 98.17) mg KOH/g, phenolic content (36.40 and 53.00) mg GAE/g extract, chlorophylls (0.52 and 0.60) mg/kg oil and carotenoids contents (1.92 and 1.88) mg/kg oil. Gas chromatography analysis revealed that linoleic (52.03 and 52.2%), oleic (31.75 and 31.84%) and palmitic (11.09 and 11.34 %) acids were the major fatty acids in the two oils. Specific extinctions at 232 nm (K232) and 270 nm (K270) were (0.58 and 0.44) and (0.42 and 0.33), respectively. The DSC melting curve showed that their melting points and melting enthalpies were (-28.05°C and 76.8 J/g) and (-27.47°C and 62.3 J/g), respectively. On the other hand, the evaluation of their DPPH radical scavenging, total antioxidant capacity, antibacterial and acetylcholinesterase activities showed interesting results. Thus, Phalaris canariensis seeds oils could deserve further consideration and investigation as a potentially new multi-purpose product for agro-food, medicinal and cosmetic uses.

Metabolites and Biological Activities of Thymus zygis, Thymus pulegioides, and Thymus fragrantissimus Grown under Organic Cultivation.

Thymus plants are marketed for diverse usages because of their pleasant odor, as well as high nutritional value and wealth of health-promoting phytochemicals. In this study, Thymuszygis, Thymuspulegioides, and Thymusfragrantissimus grown under organic cultivation regime were characterized regarding nutrients and phenolic compounds. In addition, the antioxidant and antibacterial properties of these species were screened. The plants were particularly notable for their high K/Na ratio, polyunsaturated fatty acids content and low omega-6/omega-3 fatty acids ratios, which are valuable features of a healthy diet. Caffeic acid and/or its derivatives, mainly rosmarinic acid and caffeoyl rosmarinic acid, represented the majority of the phenolic constituents of these plants, although they were less representative in T. pulegioides, which in turn was the richest in flavones. The latter species also exhibited the highest antioxidant capacity (DPPH● EC50 of 9.50 ± 1.98 µg/mL and reducing power EC50 of 30.73 ± 1.48 µg/mL), while T. zygis was the most active towards Gram-positive and Gram-negative bacteria. Overall, the results suggest that the three thyme plants grown in organic farming are endowed with valuable metabolites that give them high commercial value for applications in different industries.

Green leafy vegetables in diets with a 25:1 omega-6/omega-3 fatty acid ratio modify the erythrocyte fatty acid profile of spontaneously hypertensive rats.

BACKGROUND: In addition to the actual composition of the diet (i.e. nutrient composition, food groups), the omega-6/omega-3 fatty acid ratio has been demonstrated to influence the tissue fatty acid profile and subsequently the risk for cardiovascular and other diseases. Likewise, the consumption of green leafy vegetables (GLVs) may favorably reduce the risks associated with disease. Although an ~ 3:1 omega-6/omega-3 fatty acid ratio (ω-6/ω-3 FAR) is recommended, the typical American diet has an ~ 25:1 ω-6/ω-3 FAR. Previous research affirms the ability of collard greens (CG), purslane (PL), and sweet potato greens (SPG) to improve the hepatic profile of spontaneously hypertensive rats (SHRs). The aim of the present study was to determine the influence of GLVs, incorporated (4%) into diets with a 25:1 ω-6/ω-3 FAR, on the erythrocyte fatty acid profile of male SHRs. METHODS: SHRs (N = 50) were randomly assigned to one of five dietary groups - standardized control (AIN-76A), Control (25:1 ω-6/ω-3 FAR), CG (25:1 ω-6/ω-3 FAR + 4% CG), PL (25:1 ω-6/ω-3 FAR + 4% PL) or SPG (25:1 ω-6/ω-3 FAR + 4% SPG). Following 6 weeks consumption of diets, SHRs erythrocyte fatty acid profiles were determined by gas-liquid chromatography. RESULTS: Significantly lower percentages of total saturated fatty acids (p < 0.05) and greater percentages of polyunsaturated fatty acids were present among SHR erythrocytes following the consumption of diets containing CG, PL and SPG. Total polyunsaturated fatty acids were greatest among SHRs consuming diets containing purslane. CONCLUSIONS: The present study demonstrates the ability of GLVs to mitigate the potential effects of an elevated ω-6/ω-3 FAR, which may contribute to an atherogenic fatty acid profile, inflammation and disease pathogenesis. Dietary recommendations for disease prevention should consider the inclusion of these GLVs, particularly among those consuming diets with an ω-6/ω-3 FAR that may promote disease.

The Association of Fatty Acid Levels and Gleason Grade among Men Undergoing Radical Prostatectomy.

BACKGROUND: Epidemiological data suggest that omega-6 (ω-6) fatty acids (FAs) may be associated with cancer incidence and/or cancer mortality, whereas ω-3 FAs are potentially protective. We examined the association of the ratio of ω-6 to ω-3 FA (ω-6:ω-3) and individual FA components with pathological results among men with prostate cancer (PCa) undergoing radical prostatectomy. METHODS: Sixty-nine men were included in the study. Components of ω-6 (linoleic acid (LA), arachidonic acid (AA), and dihomo-γ-linolenic acid (DGLA)) and ω-3 (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)) were analyzed by liquid chromatography/mass selective detector separation. Logistic regression analysis was performed to determine association of FA with pathological high grade (Gleason ≥4+3) disease. RESULTS: The were 35 men with low grade disease (Gleason ≤3+4) and 34 men with high grade disease. Men with low grade disease were significantly younger (58y vs 61y, p = 0.012) and had lower D'Amico clinical classification (p = 0.001) compared to men with high grade disease. There was no significant association of ω-6:ω-3 with high grade disease (OR 0.93, p = 0.78), however overall ω-6, ω-3, and individual components of ω-6 and ω-3 FAs except EPA were significantly associated with high grade disease (ω-6: OR 3.37, 95% CI: 1.27,8.98; LA: OR 3.33, 95% CI:1.24,8.94; AA: OR 2.93, 95% CI:1.24,6.94; DGLA: OR 3.21, 95% CI:1.28,8.04; ω-3: OR 3.47, 95% CI:1.22,9.83; DHA: OR 3.13, 95% CI:1.26,7.74). ω-6 and ω-3 FA components were highly correlated (Spearman ρ = 0.77). CONCLUSION: Higher levels of individual components of ω-6 and ω-3FAs may be associated with higher-grade PCa. IMPACT: Studies into the causative factors/pathways regarding FAs and prostate carcinogenesis may prove a potential association with PCa aggressiveness.

High-Throughput Quantitative Lipidomics Analysis of Nonesterified Fatty Acids in Human Plasma.

We present a high-throughput, nontargeted lipidomics approach using liquid chromatography coupled to high-resolution mass spectrometry for quantitative analysis of nonesterified fatty acids. We applied this method to screen a wide range of fatty acids from medium-chain to very long-chain (8 to 24 carbon atoms) in human plasma samples. The method enables us to chromatographically separate branched-chain species from their straight-chain isomers as well as separate biologically important ω-3 and ω-6 polyunsaturated fatty acids. We used 51 fatty acid species to demonstrate the quantitative capability of this method with quantification limits in the nanomolar range; however, this method is not limited only to these fatty acid species. High-throughput sample preparation was developed and carried out on a robotic platform that allows extraction of 96 samples simultaneously within 3 h. This high-throughput platform was used to assess the influence of different types of human plasma collection and preparation on the nonesterified fatty acid profile of healthy donors. Use of the anticoagulants EDTA and heparin has been compared with simple clotting, and only limited changes have been detected in most nonesterified fatty acid concentrations.

Effects of n-6 and n-3 polyunsaturated acid-rich soybean phosphatidylcholine on membrane lipid profile and cryotolerance of human sperm.

OBJECTIVE: To study the effects of n-6 and n-3 polyunsaturated acid-rich soybean phosphatidylcholine (soy-PC) on sperm cryotolerance with regard to sperm membrane lipid profile, membrane surface integrity, and routine semen parameters. DESIGN: Experimental study. SETTING: University-affiliated tertiary hospital. PATIENT(S): A total of 20 normospermic fertile men. INTERVENTION(S): Semen samples examined for differences in semen parameters, sperm membrane lipid profile, and plasma membrane surface both before and after cryopreservation using basic freezing medium with N-tris(hydroxymethyl)-methyl-2-aminoethane sulfonic acid (TES) and tris-(hydroxymethyl)-aminomethane (TRIS) supplemented with purified soy-PC (TEST-PC) or egg yolk (TEST-Y), both alone or in association (TEST-Y-PC). MAIN OUTCOME MEASURE(S): Conventional semen parameters and membrane lipid profile by matrix-assisted laser/desorption ionization mass spectrometry (MALDI-MS). RESULT(S): Postthaw sperm cell motility, vitality, and morphology parameters were similar for soy-PC (TEST-PC) and egg yolk (TEST-Y) cryoprotectants. However, sperm exposed to TEST-Y-PC presented better kinetic parameters, which were similar to the original quality of the fresh semen. Human sperm MALDI-MS lipid profiles revealed that the relative abundance of glycerophospholipids of m/z 760.44 [PC (34:1)+H]+, 781.55 [SM (20:0) +Na]+, 784.55 [PC (36:3) +H]+, 806.64 [PC (38:6) +H]+, 807.64 [SM (22:1) +Na]+, and 809.64 [SM (22:0) +Na]+ increased in soy-PC samples (TEST-PC). Nonetheless, only one lipid (m/z 781.55, [SM (20:0) +Na]+) statistically significantly changed when sperm was cryopreserved in TEST-Y-PC. CONCLUSION(S): Sphingomyelin was defined as a prospective biomarker of soy-PC treatment, and it could be related to the positive cryoprotective effects of soy-PC in human sperm, opening new perspectives to design of a more efficient synthetic cryoprotectant medium containing purified egg yolk biomolecules combined with soy-PC.

Improved extraction of saturated fatty acids but not omega-3 fatty acids from sheep red blood cells using a one-step extraction procedure.

Several methods are available to extract total lipid and methylate fatty acids from a range of samples including red blood cells (RBC). Fatty acid analysis of human RBC can be undertaken using a two-step extraction and methylation or a combined one-step extraction and methylation procedure. The lipid composition of sheep RBC differs significantly from that of humans and may affect their extraction. The purpose of the current study was to examine the efficiency of extraction of lipid and detection of fatty acids from sheep RBC using a one-step procedure. Fatty acids were analysed using a one-step extraction and methylation procedure using methanol:toluene and acetyl chloride in comparison with a two-step procedure involving extraction of lipid using chloroform:methanol and separate methylation. Concentrations of saturated fatty acids including C16:0 and C18:0 were significantly higher (42.6 and 33.9 % respectively) following extraction using the one-step procedure compared with the two-step procedure. However, concentrations of some polyunsaturated fatty acids, including C20:5n-3 and C22:6n-3 were not significantly different between either procedure. The improved detection of fatty acids may be related to the ability of different solvents to extract different lipid fractions. The differential extraction of lipids and detection of fatty acids from sheep RBC may have important implications in studies examining the effect of dietary treatment on the possible health benefits of fatty acids.

Isolation of two anti-inflammatory and one pro-inflammatory polyunsaturated fatty acids from the brown seaweed Undaria pinnatifida.

Two anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs) of stearidonic acid (SA) and eicosapentaenoic acid (EPA) and one pro-inflammatory omega-6 PUFA of arachidonic acid (AA) were isolated from the edible brown seaweed Undaria pinnatifida. SA was active against mouse ear inflammation induced by phorbol myristate acetate, with IC50 values of 160, 314, and 235 microg per ear for edema, erythema, and blood flow, respectively. EPA was also active against edema, erythema, and blood flow, with IC50 values of 230, 462, and 236 microg per ear, respectively. Although AA at low concentrations showed anti-inflammatory activities when measured 10 h later, AA doses of more than 243 microg per ear induced inflammatory symptoms 1 h later. Mature thalli generally had larger amounts of PUFAs than young thalli. The algal blade contained more omega-3 PUFAs than were found in other parts, while the holdfast contained extremely high amounts of AA. Late-season thalli showed increased amounts of PUFAs, especially AA.