scholarly journals OVER-EXPRESSION OF GENE ENCODING FATTY ACID METABOLIC ENZYMES IN FISH

2008 ◽  
Vol 3 (2) ◽  
pp. 89
Author(s):  
Alimuddin Alimuddin ◽  
Goro Yoshizaki ◽  
Toshio Takeuchi ◽  
Odang Carman
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Transgenic Fish ◽  
Metabolic Enzymes ◽  
Whole Body ◽  
Fish Oils ◽  
Farmed Fish ◽  
Gene Encoding ◽  
Over Expression ◽  
Epa And Dha

Eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) have important nutritional benefits in humans. EPA and DHA are mainly derived from fish, but the decline in the stocks of major marine capture fishes could result in these fatty acids being consumed less. Farmed fish could serve as promising sources of EPA and DHA, but they need these fatty acids in their diets. Generation of fish strains that are capable of synthesizing enough amounts of EPA/DHA from the conversion of α-linolenic acid (LNA, 18:3n-3) rich oils can supply a new EPA/DHA source. This may be achieved by over-expression of genes encoding enzymes involved in HUFA biosynthesis. In aquaculture, the successful of this technique would open the possibility to reduce the enrichment of live food with fish oils for marine fish larvae, and to completely substitute fish oils with plant oils without reducing the quality of flesh in terms of EPA and DHA contents. Here, three genes, i.e. Δ6-desaturase-like (OmΔ6FAD), Δ5-desaturase-like (OmΔ5FAD) and elongase-like (MELO) encoding EPA/DHA metabolic enzymes derived from masu salmon (Oncorhynchus masou) were individually transferred into zebrafish (Danio rerio) as a model to increase its ability for synthesizing EPA and DHA. Fatty acid analysis showed that EPA content in whole body of the second transgenic fish generation over-expressing OmΔ6FAD gene was 1.4 fold and that of DHA was 2.1 fold higher (P<0.05) than those in non-transgenic fish. The EPA content in whole body of transgenic fish over-expressing OmΔ5FAD gene was 1.21-fold, and that of DHA was 1.24-fold higher (P<0.05) than those in nontransgenic fish. The same patterns were obtained in transgenic fish over-expressing MELO gene. EPA content was increased by 1.30-fold and DHA content by 1.33-fold higher (P<0.05) than those in non-transgenic fish. The results of studies demonstrated that fatty acid content of fish can be enhanced by over-expressing gene encoding enzymes involved in fatty acid biosynthesis, and perhaps this could be applied to tailor farmed fish as even better sources of valuable human food.

scholarly journals Production and Refinement of Omega-3 Rich Oils from Processing By-Products of Farmed Fish Species

Foods ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 125 ◽  
Author(s):  
Vida Šimat ◽  
Jelena Vlahović ◽  
Barbara Soldo ◽  
Danijela Skroza ◽  
Ivica Ljubenkov ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Oxidative Stability ◽  
Volatile Compounds ◽  
Fish Species ◽  
Quality Parameters ◽  
Fish Oils ◽  
Volatile Components ◽  
Farmed Fish ◽  
By Products

In this study, the effect of a four-stage chemical refining process (degumming, neutralization, bleaching, deodorization) on the quality parameters, fatty acid composition and volatile compounds of crude oils produced from processing by-products of farmed fish species (tuna, seabass and gilthead seabream) was evaluated. The quality of the oils was compared to commercially available cod liver oil on the basis of free fatty acid, peroxide value, p-anisidine, total oxidation (TOTOX), thiobarbituric acid reactive species (TBARS), oxidative stability at 80, 100 and 120 °C, tocopherol content, and volatile components, while the fatty acid profile and the proportion of polyunsaturated fatty acids (PUFAs) were used as an indicator of the nutritional values of fish oils. Quality parameters of the studied oils and oil oxidative stability were enhanced with refining and were within the limits recommended for fish oils without the loss of PUFAs. In tuna by-product refined oils, the proportion of PUFAs was over 40%, with 30% of eicosapentaenoic and docosahexaenoic fatty acids. The volatile compounds of the oils were quantified (in mg/kg) and major components were 2,4-heptadienal, pentadecane, 2,4-decadienal, 2,4-nonadienal and dodecane. The use of aquaculture by-products as an alternative source for fish oil production could contribute to a more sustainable and profitable aquaculture production, providing economic benefits for the producers and setting new standards for a fish by-product disposal strategy.

scholarly journals Effect of polyunsaturated fatty acid supplementation on milk production – review on health effects and cow milk characteristics

2018 ◽  
Vol 22 (1) ◽  
pp. 9-21
Author(s):  
Paul Joseph Mwau Mwangi ◽  
György Bázár ◽  
Tamás Tóth
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Health Effects ◽  
The Body ◽  
Cow Milk ◽  
Fish Oils ◽  
Negative Effects ◽  
Animal Products ◽  
Epa And Dha

The polyunsaturated fatty acids (PUFA) of the n-3 and n-6 group are important in the human body. It is therefore important that these fatty acids are consumed in the right amount and correct proportion so as to maintain a healthy physiological status in the body. Certain foods are naturally rich in these fatty acids, such as sea foods and some oilseeds. Fish and fish oils are rich in eicosapentanoic acid (EPA) and docosahexanoic acid (DHA) which are n-3 fatty acids, they play a crucial role in improving the physiological and health outcomes in conditions such as cardiovascular diseases, cancer, immune suppression and mental health. These fatty acids have also been shown to play beneficial role during pregnancy and lactation. Linolenic acid (LNA) which is abundant in oilseeds such linseed is a precursor of EPA and DHA in the human and therefore can be converted when need be, however the conversion is not very efficient and therefore cannot be used as a substitute. With the current deteriorating state of the global supply of fish and the high demand of energy causing diversion of resources to produce biofuels, the availability of these natural sources of n-3 and n-6 foods is growing ever scarce. Feeding of full-fat linseed and/or linseed oil has been shown to substantially increase the content of LNA in animal products such as meat, eggs and milk. On the other hand, fish oil supplementation in animal feeds also leads to a substantial increase in EPA and DHA to levels that can positive health effects to the public. Due to this potential to increase the amount of n-3 polyunsaturated fatty acids in animal products, it is seen as a simpler and cheaper way to deliver an increase in consumption to the wider public in a sustainable manner. This is due to the fact that products such as milk and eggs are more widely distributed and available in the market. Some challenges are of course present, such as negative effects due to the oxidative stability of polyunsaturated fatty acids which can have negative effects on rumen function and product organoleptic characteristics. To offset the problem of rumen biohydrogenation of PUFA, various methods of protecting the seed and fish oils have been devised, allowing for feeding even higher doses without impacting negatively on production and product quality. Keywords: PUFA, fatty acid profile, cow, organoleptic

Meal composition affects postprandial fatty acid oxidation

1993 ◽  
Vol 264 (6) ◽  
pp. R1065-R1070 ◽  
Author(s):  
D. M. Surina ◽  
W. Langhans ◽  
R. Pauli ◽  
C. Wenk
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Nutrient Utilization ◽  
Whole Body ◽  
Acid Oxidation ◽  
Plasma Ffa ◽  
Hepatic Fatty Acid Oxidation ◽  
Beta Hydroxybutyrate ◽  
Chain Fatty Acids

The influence of macronutrient content of a meal on postprandial fatty acid oxidation was investigated in 13 Caucasian males after consumption of a high-fat (HF) breakfast (33% carbohydrate, 52% fat, 15% protein) and after an equicaloric high-carbohydrate (HC) breakfast (78% carbohydrate, 6% fat, 15% protein). The HF breakfast contained short- and medium-chain fatty acids, as well as long-chain fatty acids. Respiratory quotient (RQ) and plasma beta-hydroxybutyrate (BHB) were measured during the 3 h after the meal as indicators of whole body substrate oxidation and hepatic fatty acid oxidation, respectively. Plasma levels of free fatty acids (FFA), triglycerides, glucose, insulin, and lactate were also determined because of their relationship to nutrient utilization. RQ was significantly lower and plasma BHB was higher after the HF breakfast than after the HC breakfast, implying that more fat is burned in general and specifically in the liver after an HF meal. As expected, plasma FFA and triglycerides were higher after the HF meal, and insulin and lactate were higher after the HC meal. In sum, oxidation of ingested fat occurred in response to a single HF meal.

The fatty acid composition of grass silages

1998 ◽  
Vol 1998 ◽  
pp. 35-35 ◽  
Author(s):  
R.J. Dewhurst ◽  
P.J. King
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Linolenic Acid ◽  
Saturated Fatty Acids ◽  
Fish Oils ◽  
Omega 3 ◽  
Human Diet ◽  
Omega 3 Fatty Acid ◽  
Grass Silage

Ruminant products have been criticised for the possible adverse effects of their saturated fatty acids on human health. Conversely, the omega-3 polyunsaturated fatty acids, notably those in fish oils, have been identified as beneficial components of the human diet. Earlier studies have shown that a small, but useful, amount of forage α-linolenic acid (C18:3), an omega-3 fatty acid, appears in ruminant products (Wood and Enser, 1996). The objective of the current work was to evaluate the range of α-linolenic acid concentrations in laboratory grass silages in order to assess the opportunities to modify ensiling techniques to increase the natural delivery of omega-3 fatty acid from grass silage to milk or meat.

scholarly journals Clinical translation of 18F-fluoropivalate – a PET tracer for imaging short-chain fatty acid metabolism: safety, biodistribution, and dosimetry in fed and fasted healthy volunteers

2020 ◽  
Vol 47 (11) ◽  
pp. 2549-2561 ◽  
Author(s):  
Suraiya R. Dubash ◽  
Nicholas Keat ◽  
Kasia Kozlowski ◽  
Chris Barnes ◽  
Louis Allott ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Healthy Volunteers ◽  
Effective Dose ◽  
Short Chain Fatty Acid ◽  
Safety Data ◽  
Chain Fatty Acid ◽  
Short Chain ◽  
Whole Body ◽  
Residence Times

Abstract Background Fatty acids derived de novo or taken up from the extracellular space are an essential source of nutrient for cell growth and proliferation. Radiopharmaceuticals including 11C-acetate, and 18F-FAC (2-18F-fluoroacetate), have previously been used to study short-chain fatty acid (SCFA) metabolism. We developed 18F-fluoropivalate (18F-FPIA; 3-18F-fluoro-2,2-dimethylpropionic acid) bearing a gem-dimethyl substituent to assert metabolic stability for studying SCFA metabolism. We report the safety, biodistribution, and internal radiation dosimetry profile of 18F-FPIA in 24 healthy volunteers and the effect of dietary conditions. Materials and methods Healthy volunteer male and female subjects were enrolled (n = 24), and grouped into 12 fed and 12 fasted. Non-esterified fatty acids (NEFA) and carnitine blood measurements were assessed. Subjects received 159.48 MBq (range, 47.31–164.66 MBq) of 18F-FPIA. Radiochemical purity was > 99%. Safety data were obtained during and 24 h after radiotracer administration. Subjects underwent detailed multiple whole-body PET/CT scanning with sampling of venous bloods for radioactivity and radioactive metabolite quantification. Regions of interest were defined to derive individual and mean organ residence times; effective dose was calculated using OLINDA 1.1. Results All subjects tolerated 18F-FPIA with no adverse events. Over 90% of radiotracer was present in plasma at 60 min post-injection. The organs receiving highest absorbed dose (in mGy/MBq) were the liver (0.070 ± 0.023), kidneys (0.043 ± 0.013), gallbladder wall (0.026 ± 0.003), and urinary bladder (0.021 ± 0.004); otherwise there was low tissue uptake. The calculated effective dose using mean organ residence times over all 24 subjects was 0.0154 mSv/MBq (SD ± 0.0010). No differences in biodistribution or dosimetry were seen in fed and fasted subjects, though systemic NEFA and carnitine levels reflected fasted and fed states. Conclusion The favourable safety, imaging, and dosimetric profile makes 18F-FPIA a promising candidate radiotracer for tracing SCFA metabolism.

scholarly journals The source of fatty acids incorporated into proliferating lymphoid cells in immune-stimulated lymph nodes

2003 ◽  
Vol 89 (3) ◽  
pp. 375-382 ◽  
Author(s):  
Caroline M. Pond ◽  
Christine A. Mattacks
Keyword(s):  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Lymph Nodes ◽  
Guinea Pigs ◽  
Lymphoid Cells ◽  
Whole Body ◽  
Immune Stimulation ◽  
Mesenteric Lymph Nodes ◽  
Fatty Acid Compositions

To explore the hypothesis that proliferating lymphoid cells in immune-stimulated lymph nodes obtain nutrients locally from adjacent adipose tissue, adult guinea pigs were fed for 6 weeks on standard chow or on chow supplemented with 100 g suet, sunflower oil or fish oi/g. All the guinea pigs ate standard chow for the last 5 d, during which swelling of one popliteal lymph node was stimulated by repeated local injection of lipopolysaccharide. The fatty acid compositions of phospholipids in both popliteal and in several mesenteric lymph nodes, and of triacylglycerols in eleven samples of adipose tissue defined by their anatomical relations to lymph nodes, were determined by GC. The proportions of fatty acids in the phospholipids extracted from the stimulated popliteal node correlated best with those of triacylglycerols in the surrounding adipocytes, less strongly with those of adipocytes elsewhere in depots associated with lymphoid tissue, but not with those of nodeless depots. The composition of triacylglycerols in the perinodal adipose tissue changed under local immune stimulation. We conclude that proliferating lymphoid cells in activated lymph nodes obtain fatty acids mainly from the triacylglycerols in adjacent perinodal adipose tissue. Immune stimulation prompts changes in the fatty acid composition of the triacylglycerols of adipocytes in node-containing depots that equip the adipose tissue for provisioning immune responses. Such local interactions show that specialised adipocytes can act as an interface between whole-body and cellular nutrition, and may explain why mammalian adipose tissue is partitioned into a few large and many small depots.

scholarly journals A High-Throughput Fatty Acid Profiling Screen Reveals Novel Variations in Fatty Acid Biosynthesis in Chlamydomonas reinhardtii and Related Algae

2014 ◽  
Vol 13 (11) ◽  
pp. 1431-1438 ◽  
Author(s):  
Erin L. Pflaster ◽  
Michael J. Schwabe ◽  
Joyanne Becker ◽  
Melissa S. Wilkinson ◽  
Ashley Parmer ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Biosynthesis ◽  
Methyl Esters ◽  
Screening Method ◽  
Laboratory Strain ◽  
Gene Encoding ◽  
Preparation Methods ◽  
Content Type ◽  
Species Specific

ABSTRACTAnalysis of fatty acid methyl esters (FAMEs) by gas chromatography (GC) is a common technique for the quantitative and qualitative analysis of acyl lipids. Methods for FAME preparation are typically time-consuming and labor-intensive and require multiple transfers of reagents and products between reaction tubes and autosampler vials. In order to increase throughput and lower the time and materials costs required for FAME preparation prior to GC analysis, we have developed a method in which 10-to-20-mg samples of microbial biomass are transferred to standard GC autosampler vials, transesterified using an emulsion of methanolic trimethylsulfonium hydroxide and hexane, and analyzed directly by GC without further sample handling. This method gives results that are essentially identical to those obtained by the more labor- and material-intensive FAME preparation methods, such as transmethylation with methanolic HCl. We applied this method to the screening of laboratory and environmental isolates of the green algaChlamydomonasfor variations in fatty acid composition. This screening method facilitated two novel discoveries. First, we identified a common laboratory strain ofC. reinhardtii, CC-620, completely lacking all ω-3 fatty acids normally found in this organism and showed that this strain contains an inactivating mutation in the CrFAD7 gene, encoding the sole ω-3 desaturase activity in this organism. Second, we showed that some species ofChlamydomonasmake Δ6-unsaturated polyunsaturated fatty acids (PUFA) rather than the Δ5 species normally made by the previously characterized laboratory strains ofChlamydomonas, suggesting that there is species-specific variation in the regiospecificity and substrate selectivity of front-end desaturases in this algal genus.

The 1990 Borden Award Lecture Dietary regulation of fatty acid and triglyceride metabolism

1991 ◽  
Vol 69 (11) ◽  
pp. 1637-1647 ◽  
Author(s):  
Gene R. Herzberg
Keyword(s):  
Skeletal Muscle ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Lipoprotein Lipase ◽  
Fatty Acid Synthesis ◽  
Dietary Fat ◽  
Acid Synthesis ◽  
Fish Oils ◽  
Dietary Fish

The level of circulating triacylglycerols is determined by the balance between their delivery into the plasma and their removal from it. Plasma triacylglycerols are derived either from dietary fat as chylomicrons or from endogenous hepatic synthesis as very low density lipoproteins. Their removal occurs through the action of lipoprotein lipase after which the fatty acids are either stored in adipose tissue or oxidized, primarily in skeletal muscle and heart. The composition of the diet has been shown to influence many of these processes. Hepatic fatty acid synthesis and triacylglycerol secretion are affected by the quantity and composition of dietary fat, carbohydrate, and protein. Polyunsaturated but not saturated fats reduce hepatic fatty acid synthesis by decreasing the amount of the lipogenic enzymes needed for de novo fatty acid synthesis. Dietary fish oils are particularly effective at reducing both fatty acid synthesis and triacylglycerol secretion and as a result are hypotriacylglycerolemic, particularly in hypertriacylglycerolemic individuals. In addition, dietary fish oils can increase the oxidation of fatty acids and lead to increased activity of lipoprotein lipase in skeletal muscle and heart. It appears that the hypotriacylglycerolemic effect of dietary fish oils is mediated by effects on both synthesis and removal of circulating triacylglycerols.Key words: lipid, fish oil, fructose, liver, adipose tissue, oxidation.

Relationship Between Vitamin E Requirement and Polyunsaturated Fatty Acid Intake in Man: a Review

2000 ◽  
Vol 70 (2) ◽  
pp. 31-42 ◽  
Author(s):  
Valk ◽  
Gerard Hornstra
Keyword(s):  
Lipid Peroxidation ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Vitamin E ◽  
Unsaturated Fatty Acids ◽  
Active Form ◽  
Animal Experiments ◽  
Alpha Tocopherol ◽  
Quantitative Relation ◽  
Epa And Dha

Vitamin E is the general term for all tocopherols and tocotrienols, of which alpha-tocopherol is the natural and biologically most active form. Although gamma-tocopherol makes a significant contribution to the vitamin E CONTENT in foods, it is less effective in animal and human tissues, where alpha-tocopherol is the most effective chain-breaking lipid-soluble antioxidant. The antioxidant function of vitamin E is critical for the prevention of oxidation of tissue PUFA. Animal experiments have shown that increasing the degree of dietary fatty acid unsaturation increases the peroxidizability of the lipids and reduces the time required to develop symptoms of vitamin E deficiency. From these experiments, relative amounts of vitamin E required to protect the various fatty acids from being peroxidized, could be estimated. Since systematic studies on the vitamin E requirement in relation to PUFA consumption have not been performed in man, recommendations for vitamin E intake are based on animal experiments and human food intake data. An intake of 0.6 mg alpha-tocopherol equivalents per gram linoleic acid is generally seen as adequate for human adults. The minimum vitamin E requirement at consumption of fatty acids with a higher degree of unsaturation can be calculated by a formula, which takes into account the peroxidizability of unsaturated fatty acids and is based on the results of animal experiments. There are, however, no clear data on the vitamin E requirement of humans consuming the more unsaturated fatty acids as for instance EPA (20:5, n-3) and DHA (22:6, n-3). Studies investigating the effects of EPA and DHA supplementation have shown an increase in lipid peroxidation, although amounts of vitamin E were present that are considered adequate in relation to the calculated oxidative potential of these fatty acids. Furthermore, a calculation of the vitamin E requirement, using recent nutritional intake data, shows that a reduction in total fat intake with a concomitant increase in PUFA consumption, including EPA and DHA, will result in an increased amount of vitamin E required. In addition, the methods used in previous studies investigating vitamin E requirement and PUFA consumption (for instance erythrocyte hemolysis), and the techniques used to assess lipid peroxidation (e.g. MDA analysis), may be unsuitable to establish a quantitative relation between vitamin E intake and consumption of highly unsaturated fatty acids. Therefore, further studies are required to establish the vitamin E requirement when the intake of longer-chain, more-unsaturated fatty acids is increased. For this purpose it is necessary to use functional techniques based on the measurement of lipid peroxidation in vivo. Until these data are available, the widely used ratio of at least 0.6 mg alpha-TE/g PUFA is suggested. Higher levels may be necessary, however, for fats that are rich in fatty acids containing more than two double bonds.

Sign in / Sign up

Export Citation Format

Share Document