Higher Eicosapentaenoic Acid Research Articles

Effects of dietary microalgae on fatty acids and digestive enzymes in copepodCyclopina kasignete, a potential live food for fish larvae

The copepod Cyclopina kasignete is a potential live food in aquaculture and its fatty acid components and digestive enzymes were investigated. Three dry algal products (mixed algae, Melosira sp. and Nannochloropsis oculata) and two fresh microalgae (Tisochrysis lutea and N. oculata) were fed to the copepod for 30 days. The essential fatty acids (EFA) in copepods were altered by feeding different types of dry algae. The copepod fed dry Melosira sp. or fresh T. lutea contained higher eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (ARA), protease and trypsin than fed on other algae. The copepod contained a similar fatty acid profile and digestive enzymes by feeding either dry or fresh N. oculata. Between fresh algal species, the copepod fed T. lutea contained higher EPA, DHA and ARA than that fed fresh N. oculata. The amounts of EPA and DHA in copepods were more concentrated than those in the dietary algae, suggesting that the copepod has the ability to accumulate some EFA. This study indicates that dietary algae can modify the nutritional composition and in digestive enzymes copepods, which in turn may be able to transfer suitable nutrients and digestive enzymes to fish larvae in aquaculture.

Food Sources of EPA and DHA in the Diets of American Children, NHANES 2003-2010

Objective Dietary eicosapentaenoicacid (EPA) and docosahexaenoic acid (DHA) are found in the highest concentrations in fish and seafood. As important nutrients for brain and eye development and function, their consumption levels are of public health interest, especially in children. This study was conducted toexamine children’sreported consumption of fish and shellfish as well as EPA and DHA intake. Methods Secondary analysis of dietary intake (24-hour recall) and Food Frequency Questionnaire (FFQ) data ascertaining habitual fish and seafood intake of 2-18 year olds (N=13,441) participating in the 2003-2004, 2005-2006, 2007-2008, and 2009-2010 National Health and Nutrition Examination Survey (NHANES). All analyses were survey design corrected and weighted (one-day dietary intake weight) and conducted for the total sample by age group (2-5, 6-11, 12-18 year olds); analysis was conducted for EPA and DHA combined. Results Less than 50% of the children consumed fish (49.0%) or shellfish (35.9%) and only 0.3% of the population consumed fish high in EPA and DHA. Children consumed, on average, less than 25% of the recommended amount of EPA and DHA. The foods that contributed the highest average of EPA and DHA to the diet were canned sardines, cooked salmon, and fried carp. The EPA and DHA-containing foods consumed by at least one child in the population with the highest EPA and DHA densities were sturgeon roe, baked/broiled mackerel, and sardines. Conclusions Results of this nationally representative study of 2-18 year olds show that children had suboptimal consumption of fish and shellfish, and EPA and DHA reported intakes were much below the recommended amounts. Further research is needed to examine the barriers to higher fish and shellfish consumption and to develop effective ways to increase children’s dietary intake of EPA and DHA. Introduction The human body has the ability to elongate and desaturate alphalinolenic acid (ALA) to the long chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) [1-3]. However, Western diets are low in n-3 PUFAs, specifically ALA found in plant oils and EPA and DHA found in oily fish [4-6]. In the United States (US), the mean intake of n-3 PUFAs is 0.7% of total energy consumed [7], and intake in adults is very low with a median intake of EPA and DHA only contributing 0.05% of total dietary energy[7, 8]. Even individuals with low fish consumption have greater n-3 PUFA status than those individuals who do not consume any fish [9]. Western diets low in n-3 PUFAs and high in n-6 PUFAs contribute to poor brain development and function [4, 10]. It is uncertain if the rate of DHA synthesis in the human body is sufficient to support optimal brain and retinal development, and these PUFA swould ideally be provided in the diet [11]. DHA is the major n-3 PUFA esterified in glycerophospholipids through the action of acyl-CoA synthases and acyl-CoA:lysophospholipid acyltransferases [12], that forms the structural matrix of brain grey matter and retinal membranes [13, 14]. In addition, dietary intake of n-6 PUFAs play a role since n-6 PUFAs interact and compete with n-3 PUFAs in the fatty acid metabolic pathway [15-21].

A euryhaline Nannochloropsis gaditana with potential for nutraceutical (EPA) and biodiesel production

The holy grail of the present work was to study the effects of salinity (20, 30, 35, and 40g/L), light intensity (60 and 150μmolphotonsm−2s−1) and photoperiod (24h:0h, 18h:06h, 12h:12h, 06h:18h and 00h:24h light:dark) on selective nutraceutical properties of Nannochloropsis gaditana with a focus on eicosapentaenoic acid production. The maximal biomass (45.01±1.01mgL−1day−1) and lipid productivities (14.63±0.79mgL−1day−1) were obtained at a salinity gradient of 20g/L, whereas the maximal eicosapentaenoic acid (EPA) productivity was found at 60μmolphotonsm−2s−1 and a photoperiod regime of 18h:06h (light:dark), which yielded high EPA contents of 37.83±0.37% and 32.16±0.40%, respectively. Low salinity augmented both the chlorophyll-a and carotenoid contents (11.71±0.40 and 4.32±0.15μg/mL, respectively) compared with high salinity. The eicosapentaenoic acid (C20:5) content of the strain was in the range of 19.13±0.08 to 37.83±0.37%. Principal component analysis demonstrated a correlation between saturated and monounsaturated fatty acid synthesis. After significant extraction of long-chain PUFA (EPA and AA), the residual oil can be used for the production of biodiesel that complies with the European standards for biodiesel. This study investigated the nutrient profile of EPA-enriched microalgae N. gaditana, which can be used for nutraceutical production, and established that the remaining oil (excluding EPA and AA) may be a promising biodiesel feedstock due to its high SFA and MUFA contents.

Relation of Fish Oil Supplementation to Markers of Atherothrombotic Risk in Patients With Cardiovascular Disease Not Receiving Lipid-Lowering Therapy

Fish oil supplementation (FOS) is known to have cardiovascular benefits. However, the effects of FOS on thrombosis are incompletely understood. We sought to determine if the use of FOS is associated with lower indices of atherothrombotic risk in patients with suspected coronary artery disease (sCAD). This is a subgroup analysis of consecutive patients with sCAD (n=600) enrolled in the Multi-Analyte, Thrombogenic, and Genetic Markers of Atherosclerosis study. Patients on FOS were compared with patients not on FOS. Lipid profile was determined by vertical density gradient ultracentrifugation (n=520), eicosapentaenoic acid+docosahexaenoic acid was measured by gas chromatography (n=437), and AtherOx testing was performed by immunoassay (n=343). Thromboelastography (n=419), ADP- and collagen-induced platelet aggregation (n=137), and urinary 11-dehydrothromboxane B2 levels (n=259) were performed immediately before elective coronary angiography. In the total population, FOS was associated with higher eicosapentaenoic acid+docosahexaenoic acid content (p<0.001), lower triglycerides (p=0.04), total very low-density lipoprotein cholesterol (p=0.002), intermediate-density lipoprotein cholesterol (p=0.02), and AtherOx levels (p=0.02) but not in patients on lipid-lowering therapy. Patients not on lipid-lowering therapy taking FOS had lower very low-density lipoprotein cholesterol, intermediate-density lipoprotein cholesterol, remnant lipoproteins, triglycerides, low-density lipoprotein cholesterol, AtherOx levels, collagen-induced platelet aggregation, thrombin-induced platelet-fibrin clot strength, and shear elasticity (p<0.03 for all). In clopidogrel-treated patients, there was no difference in ADP-induced aggregation between FOS groups. Patients on FOS had lower urinary 11-dehydrothromboxane B2 levels regardless of lipid-lowering therapy (p<0.04). In conclusion, the findings of this study support the potential benefit of FOS for atherothrombotic risk reduction in sCAD with the greatest benefit in patients not receiving lipid-lowering therapy. Future prospective studies to compare FOS with lipid-lowering therapy and to assess the independent effects of FOS on thrombogenicity are needed.

Fatty acid compositions of silver catfish, Pangasius sp. farmed in several rivers of Pahang, Malaysia.

Pangasius micronemus (Black Pangasius sp.) and Pangasius nasutus (Fruit Pangasius sp.) are two species of silver catfish widely consumed in Malaysia. The present study evaluated fatty acid profiles of fish muscles in these two Pangasius sp. from different farms and locations to determine which species or location is better in term of lipid quality. The results showed MUFAs (Monounsaturated fatty acid) content was highest (35.0-44.4%) followed by SFA (Saturated fatty acid) [32.0-41.5%] and PUFAs (polyunsaturated fatty acids) [9.3-19.3%]. P. micronemus of Sg. Kanchong displayed higher palmitic acid (SFA; 29.0%) than P. nasutus from Peramu (23.5%). In contrast, oleic acid (MUFA) revealed highest in P. nasutus (38.1%) while lowest in P. micronemus of Sg. Kanchong (29.7%). Additionally, utmost PUFAs belonged to P. micronemus of Sg. Kanchong (19.3%) and lower most in P. nasutus from Peramu (9.3%). P. micronemus presented with a higher EPA (eicosapentaenoic acid) [1.0-1.4%], DHA (Docosahexaenoic acid) [1.7-2.8%] and LA (Linoleic acid) [11.8-12.0%] than P. nasutus (EPA; 0.3%, DHA; 1.0%, LA; 4.8%). However, P. nasutus established higher GLA (gamma-linolenic acid) [0.4%] than P. micronemus (0.04-0.06%). Both Pangasius sp. can be regarded as good supplies of omega-3 and omega-6. Overall, P. micronemus from Sg. Kanchong is the best choice among all for reason high in EPA and DHA.

Growth, Survival and Fatty Acid Composition of Freshwater Crayfish (Astacus leptodactylus) Juveniles Fed Enriched Daphnia magna as an Alternative to Artemia

This experiment was conducted to investigate the effects Daphnia magna enriched with lipid emulsions as an alternative to Artemia, on growth, survival rate, and fatty acid composition of freshwater crayfish (Astacus leptodactylus Esch. 1823). The four treatment groups were (a) unenriched Artemia (UEA), (b) unenriched D. magna (UED), (c) D. magna enriched with redpepper emulsion (DER), and (d) D. magna enriched with anchovy oil emulsion (DEA). All tests were carried out in triplicate for 30 days. The crayfish (mean weight 0.12g) were fed ad libitum once daily. At the end of experiment, the highest eicosapentaenoic acid, 20:5n-3 (EPA) level was found in the DEA group (5.77%). The highest DHA (docosahexaenoic acid, 22:6n-3) level was found in the DER group (2.73%) which was statistically similar to the DEA group. In addition, high n-3 HUFA (high unsaturated fatty acid) levels were detected in enriched D. magna groups with emulsions. However, high EPA levels in enriched D. magna groups with emulsions were not reflected in crayfish tissues, but DHA level was reflected in crayfish tissues fed with anchovy oil emulsion. The crayfish fed with D. magna showed similar growth to that of the Artemia fed groups. The growth of the enriched D. magna groups did not differ.

The characteristics of TAG and EPA accumulation in Nannochloropsis oceanica IMET1 under different nitrogen supply regimes

The strategy of nitrogen limitation has been widely applied to enhance lipid production in microalgae. The changes of cellular composition, and the characteristics of triacylglycerol (TAG) and eicosapentaenoic acid (EPA) accumulation in Nannochloropsis oceanica IMET1 were investigated. The results revealed that after nitrogen limitation TAG rather than carbohydrate was the dominant carbon sink in N. oceanica IMET1. Different nitrogen supplementation strategies were applied in order to achieve high TAG and EPA productivity, respectively. Limited nitrogen was supplied to improve TAG production, and a maximum productivity of 29.44mgL−1d−1 was obtained, which was a 6.74-fold increase compared to nitrogen-depleted cultivation. The highest EPA productivity of 7.66mgL−1d−1 was achieved under nitrogen-replete cultivation, which is different from the condition for TAG maximum productivity because the EPA is in glycolipids and phospholipids mainly. The fatty acid composition analysis identified the source of acyl group in TAG accumulation.

Abstract 14785: Oral Administration of Eicosapentaenoic Acid Ameliorates Anti-inflammatory Functions of High-Density Lipoprotein in Dyslipidemic Patients

Objective: Previous studies have reported that inflammation converts high-density lipoprotein (HDL) to dysfunctional form lacking its anti-inflammatory properties. However, little is known about pharmacological therapy to improve HDL function. It has been recently postulated that fatty acid component in HDL-phospholipids modulates HDL functions. We investigated the effect of oral administration of high dose eicosapentaenoic acid (EPA) on HDL functions. Methods: Patients with dyslipidemia were treated with 1800 mg/day EPA for 4 weeks, and HDL fractions were isolated by ultracentrifuge before and after the EPA treatment. HDL functions were evaluated by multiple in vitro cell-based assays. Results: The EPA treatment did not affect the quantity in the serum lipid profile including serum cholesterol, triglyceride and apolipoprotein levels, but significantly increased EPA concentrations both in the serum and HDL fraction. The EPA/arachidonic acid ratio in the HDL was in proportion to that in the serum, suggesting that EPA was incorporated in HDL particles. The HDL after EPA treatment possessed high activity of paraoxonase-1, an HDL-associated anti-oxidative enzyme, compared to HDL before EPA treatment. In addition, the EPA-rich HDL significantly improved endothelial cell migration, and markedly inhibited cytokine-induced expression of vascular cell adhesion molecule-1 in human umbilical vein endothelial cells, compared to HDL before the EPA treatment. Moreover, the EPA-rich HDL had high capacity of cholesterol efflux capacity from macrophages. Conclusion: Administration of high dose EPA improves anti-inflammatory, anti-oxidative, and cholesterol efflux capacity of HDL in dyslipidemic patients. Thus, EPA may transform “dysfunctional HDL” to “functional”, in patients with coronary risk factors.

Colt, multicenter capre open label randomized dose-ranging phase II trial to assess efficacy/safety in patients with mild-to-high hypertriglyceridemia

Objectives: Long-chain polyunsaturated omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are known to reduce hepatic secretion of triglyceride (TG)-rich lipoproteins and plasma TG levels. This study evaluated the efficacy of CaPre®, a novel highly purified omega-3 krill oil extract with a high EPA and DHA phospholipid conjugate content, to reduce fasting plasma TG ranging between 200-877 mg/dL after 4 and 8 weeks vs. Standard-Of-Care (SOC). Additional endpoints were changes in TC, LDL-C, HDL-C, non-HDL-C, HbA1c, Apo-AI, -AII, -CII, -CIII and –E.

Improving the Oxidative Stability of Krill Oil‐in‐Water Emulsions

AbstractA positively charged protein (fish gelatin) or a negatively charged protein species (heat‐treated milk protein–carbohydrate mixture) was added to a primary krill oil (KO) emulsion stabilized by the phospholipids inherent in KO, with the aim of improving the oxidative stability of KO‐in‐water emulsions at pH 8.0 (10 % KO). The positively charged fish gelatin deposited on the primary interface of the oil droplets in the primary KO‐in‐water emulsion improved the oxidative stability of the KO‐in‐water emulsion as evidenced by the higher eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) remaining and lower propanal produced after accelerated oxidation (40 °C, 25 days). The addition of the negatively charged heat‐treated milk protein–carbohydrate mixture containing Maillard reaction products (MRP) to the bulk phase of the emulsion also enhanced the oxidative stability of the KO‐in‐water emulsion. The addition of MRP to the aqueous phase of phospholipids stabilized emulsion droplets offered more protection to EPA and DHA of the KO emulsions compared to the formation of an additional layer at the interface of the KO emulsion droplet. This suggests that interventions based on addition of antioxidant species to the formulation were more effective for arresting oxidation than increasing the thickness of the droplet interface. The addition of proteins into KO containing emulsion formulations is a promising strategy for protecting omega‐3 marine phospholipids against oxidation.

Compared with Daily, Weekly n–3 PUFA Intake Affects the Incorporation of Eicosapentaenoic Acid and Docosahexaenoic Acid into Platelets and Mononuclear Cells in Humans1–3

Consumption of oily fish is sporadic, whereas controlled intervention studies of n–3 (ω-3) fatty acids usually provide capsules containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as a daily dose. This methodologic study explored whether there are differences in the short-, medium-, and long-term incorporation of EPA and DHA into blood plasma and cells with the provision of identical amounts of EPA and DHA, equivalent to 2 oily fish servings per week (or 6.54 g/wk EPA and DHA), either intermittently (i.e., 1 portion twice per week) or continuously (i.e., divided into daily amounts). The study was part of a randomized, double-blind controlled intervention lasting 12 mo, with participants stratified by age and sex. There were 5 intervention groups, 2 of which are reported here: the 2 intermittent portions (2I) and 2 continuous portions (2C) groups. EPA and DHA were measured in plasma phosphatidylcholine, platelets, and blood mononuclear cells (MNCs) at 9 time points. Sixty-five participants completed the study (2I group, n = 30, mean age of 49.2 y; 2C group, n = 35, mean age of 50.6 y). The incorporation pattern over the 12-mo intervention was different between the 2 groups in all samples (P < 0.0001, time × treatment interaction). At the end of the 12-mo intervention, the 2C group had higher EPA, DHA, and EPA + DHA in platelets (all P < 0.01) and higher EPA and EPA + DHA in MNCs (both P < 0.05) compared with the 2I group. No significant differences were shown for plasma phosphatidylcholine EPA (P = 0.1), DHA (P = 0.15), EPA + DHA (P = 0.07), or MNC DHA (P = 0.06). In conclusion, the pattern of consumption does affect the incorporation of EPA and DHA into cells used as biomarkers of intake. The differences identified here need to be considered in the design of studies and when extrapolating results from continuous capsule-based intervention studies to dietary guidelines for oily fish consumption. This trial was registered at www.controlled-trials.com> as ISRCTN48398526.

Le statut en acide eicosapentaénoïque est associé à des valeurs plus élevées de l’indice calcanéen ultrasonorestiffnesschez les femmes autochtones : résultats d’une étude longitudinale et de deux études transversales

Several studies have reported that the status in omega-3 polyunsaturated fatty acid (PUFA) and the omega-3/omega-6 PUFA ratio are positively related to bone health. This study aimed at examining the relationship between the status of different PUFAs and bone strength expressed by the stiffness index (SI) among indigenous women in northern Canada and Greenland, whose diets are rich in PUFAs compared to those of non-Aboriginals. Our study includes 118 Inuit women from Nuuk (Greenland), 195 Inuit women from Nunavik (Canada), and 249 Cree women of from East James Bay (Canada). Projects in Nunavik and in the Cree communities had a cross-sectional design and the Greenland project, a longitudinal design. The content of some PUFAs phospholipids of erythrocyte membranes was measured after transmethylation by gas chromatography coupled with a flame ionization detector. Stiffness index was measured by ultrasound at the right calcaneus with a water-bath Achilles Lunar instrument (Greenland) or an Achilles Insight instrument (Nunavik, East James Bay). Relations between SI and various PUFAs were studied using multiple linear regression analyses. Eicosapentaenoic acid (EPA) was positively and significantly associated with SI (log), even after adjustment for several confounders and covariates in all three projects. A high EPA status, resulting mainly from the consumption of fatty fish or marine mammal fat, seems to have a positive effect on bone strength measured by ultrasonography among Aboriginal women from three different populations.

Erratum to: Optimal Condition for Eicosapentaenoic Acid Production and Purification from Psychrophillic Marine Baterium Shewanella sp. L93

To obtain eicosapentaenoic acid (EPA)-producing bacteria, some 600 strains of bacteria were isolated from Antarctic sediment and marine organisms during the summer expedition of 1999-2000 and 7 EPA-producing bacteria were obtained through screening with TLC and GC. A strain designated as L93 showed the highest EPA production, which was gram-negative, rod-shaped bacterium. L93 strain was identified as Shewanella sp., from the sequence analysis of 16S rDNA. Optimal conditions temperature and pH for the growth and EPA production were about and pH 7. In addition, its production was optimized by 50%(w/v) sea salt. We establish the optimal production system to produce about 320 mg per liter by using this optimal EPA production conditions. EPA-methyl ester was purified from cultured L93 strain to a purity of higher than 97% and typical purification yield is greater than 72% of the input amount via urea complexation and HPLC.

Effect of outdoor conditions on Nannochloropsis salina cultivation in artificial seawater using nutrients from anaerobic digestion effluent

The effects of simulated outdoor seasonal climatic conditions on Nannochloropsis salina (N. salina) grown using nutrients from anaerobic digestion (AD) effluent were evaluated in this study. Under various light exposure (LE) and temperature (10-30 °C) conditions, N. salina specific growth rate (μ) was strongly affected by LE. Light availability (LA) was observed to be crucial for biomass production, with μ values of 0.038±0.013 d(-1), 0.093±0.013 d(-1), and 0.151±0.021 d(-1) for 6-h, 12-h, and 24-h LA conditions, respectively. Temperature (10-25 °C) was not significant in affecting the light dependent growth coefficient (μ/LE), indicating the suitability of culturing this strain in the Ohio climate. Cultures exposed to low illumination had significantly higher unsaturated fatty acid content than those under high illumination, with nearly 29% higher eicosapentaenoic acid (C20:5) content. Using LE and light attenuation resulted in adequate prediction of N. salina growth in a 1000 L open raceway pond.

Process development of eicosapentaenoic acid production

Eicosapentaenoic acid (EPA), a well-known member of omega-3 fatty acids, is considered to have a significant health promoting role in the human body. It is an essential fatty acid as the human body lacks the ability to produce it in vivo and must be supplemented through diet. Microbial EPA represents a potential commercial source. GC/MS analyses confirmed that bacterial isolate 717, similar to Shewanella pacifica on the basis of 16S rRNA sequencing, is a potential high EPA producer. Two types of bioreactors, a Stirred Tank Reactor (STR) and an Oscillatory Baffled Reactor (OBR), were investigated in order to choose the optimum system for EPA production. The EPA production media was optimised through the selection of media components in a Plackett–Burman (PB) design of experiment followed by a Central Composite Design (CCD) to optimise the concentration of medium components identified as significant in the Plackett–Burman experiment. The growth conditions for the bioreactor, using artificial sea water (ASW) medium, were optimised by applying Response Surface Methodology (RSM). This optimisation strategy resulted in an increase in EPA from 33mg/l (10mg/g biomass), representing 8% of the total fatty acids at shake flask level, to 350mg/l (46mg/g biomass) representing 25% of the total fatty acids at bioreactor level. During this study the main effects and the interactions between the bioreactor growth conditions were revealed and a polynomial model of EPA production was generated. Chemostat experiments were performed to test the effect of growth rate and temperature on EPA production.

Decontamination solutions for polychlorinated biphenyls (PCBs) in raw fish oils from environmentally contaminated sea fishes

Fish oil has been identified as one of the most important contributors to the levels of polychlorinated biphenyls (PCBs) in food and feed products. In this study, PCB adsorption from fish oil onto activated carbon (AC), other sustainable adsorbents (mussel shell and wood waste ashes) and organic solvent such as ethanol were compared and optimized. Regarding to adsorbents, PCBs were extracted from fish oil by a 2.0% adsorbent material dose, during 6.0h at 25°C. Solvent extraction was carried out using 2×5.0mL ethanol by manually stirring for 3.0min, and then by Ultrasound-Assisted Solvent Extraction (UASE) for 5.0min. The results showed that removal rates obtained by using adsorbent materials ranged from 0.0 to 10% for marker PCBs, from 0.0 to 37% for mono-ortho-PCBs, from 0.0 to 74% for PCB11 and from 0.0 to 95% for non-ortho-PCBs. Regarding to solvent extraction, ethanol was used by manually stirring and then by Ultrasound-Assisted Solvent Extraction (UASE). The samples were then centrifuged (2000rpm/10min) and the alcoholic phase was removed. With this method, removal efficiencies were much better (85–116%); nevertheless, high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) removal rates (70–78 and 71–79%, respectively) were detected. We can conclude that adsorption with adsorbents depends on the geometry of PCB congeners, as well as both type of adsorption material and their origin, and that several sorption cycles are needed. Adsorption with ethanol could be the most effective methodology but nutritional quality was impaired, what makes necessary to look for other not so polar removal solvents.

Engineering strategies for enhancing the production of eicosapentaenoic acid (EPA) from an isolated microalga Nannochloropsis oceanica CY2

Microalgae have emerged as promising resources for highly unsaturated fatty acids. In this study, an indigenous microalga identified as Nannochloropsis oceanica CY2 was grown photoautotrophically to produce eicosapentaenoic acid (EPA; 20:5, n-3). Specific engineering strategies were employed to stimulate EPA accumulation in the microalgal cells. The results show that BG-11 was the most effective medium to grow N. oceanica CY2, giving an EPA content and biomass concentration of 2.38% (per dry cell weight) and 1.53 g/l. The EPA content nearly doubled when using the optimal nitrogen source (NaNO3) at a concentration of 1.50 g/l. The illumination system also markedly affected the EPA content for the photoautotrophic microalga. When the microalgal culture was illuminated with a red LED, an impressively high EPA content of 5.5% was obtained. Finally, using semi-batch cultures operations with LED-blue illumination, the EPA content of N. oceanica CY2 was stably maintained at 5.0%.

Physical treatment of high EPAYarrowia lipolyticabiomass increases the availability of n-3 highly unsaturated fatty acids when fed to Atlantic salmon

A strain of Yarrowia lipolytica engineered to produce high levels of eicosapentaenoic acid (EPA) was used as feed ingredient to Atlantic salmon (Salmo salar L.). The study was designed to investigate the effect of washing and cell disruption, on growth, bioavailability, and fillet composition of Atlantic salmon growing from 0.5 to 1 kg. Four diets containing 200 g kg-1 yeast (Unwashed/Not disrupted, Unwashed/Disrupted, Washed/Undisrupted, Washed/Disrupted) were compared to a fishmeal-based control diet in a 112-day feeding experiment. Final weights and growth rates were similar for all dietary groups. Apparent lipid digestibility was highly affected by disruption of the yeast biomass. Disruption increased the apparent digestibility of EPA from 32% to 76% in washed biomass, and from 26% to 76% in Unwashed biomass. Sum n-3 fatty acids deposited in whole body was similar in fish fed the control diet and the diets with Disrupted yeast biomass, while fish fed Undisrupted biomass had significantly lower content of n-3. Removal of residual medium components by washing had no discernible effect on utilization of EPA. Evidence for conversion of EPA to DHA (docosahexaenoic acid) in the fish was indicated by deposition ratio Rd 1 for DHA.

Production of omega-3 eicosapentaenoic acid by metabolic engineering of Yarrowia lipolytica

The availability of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is currently limited because they are produced mainly by marine fisheries that cannot keep pace with the demands of the growing market for these products. A sustainable non-animal source of EPA and DHA is needed. Metabolic engineering of the oleaginous yeast Yarrowia lipolytica resulted in a strain that produced EPA at 15% of dry cell weight. The engineered yeast lipid comprises EPA at 56.6% and saturated fatty acids at less than 5% by weight, which are the highest and the lowest percentages, respectively, among known EPA sources. Inactivation of the peroxisome biogenesis gene PEX10 was crucial in obtaining high EPA yields and may increase the yields of other commercially desirable lipid-related products. This technology platform enables the production of lipids with tailored fatty acid compositions and provides a sustainable source of EPA.

Comparison of growth parameters of turkey hybrids Big BUT 6 and Converter

Although the composition of poultry meat significantly depends on the bird species, the feeding, the cuts, and the presence of skin, overall it is considered of good nutritional value and low energy content. Besides containing good amounts of proteins and many micronutrients, poultry meat is relatively low in fats and cholesterol, particularly when it is consumed without skin. An interesting nutritional characteristic of the poultry meat is to be rich in n-3 polyunsaturated fatty acids. The content of these fatty acids can be further increased using appropriate feeding, and a genotype-based selection has been also suggested to produce chicken meat with high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content, possibly representing an alternative to fish.Poultry meat also contains several bioactive components such as glutathione, taurine, anserine, and others, and the content of most of them can also be increased by appropriate feeding. Future perspective indicates poultry meat as a promising functional food.