Enzymatic Preparation, In-Depth Molecular Analysis, and In Vitro Digestion Simulation of Palmitoleic Acid (ω-7)-Enriched Fish Oil Triacylglycerols.

In this study, an enzymatic reaction was developed for synthesizing pure triacylglycerols (TAG) with a high content of palmitoleic acid (POA) using fish byproduct oil. The characteristics of synthesized structural TAGs rich in POA (POA-TAG) were analyzed in detail through ultrahigh-performance liquid chromatography Q Exactive orbitrap mass spectrometry. Optimal conditions were thoroughly investigated and determined for reaction systems, including the use of Lipozyme TL IM and Novozym 435, 15 wt % lipase loading, substrate mass ratio of 1:3, and water content of 2.5 and 0.5 wt %, respectively, resulting in yields of 67.50 and 67.45% for POA-TAG, respectively. Multivariate statistical analysis revealed that TAG 16:1/16:1/20:4, TAG 16:1/16:1/16:1, TAG 16:1/16:1/18:1, and TAG 16:0/16:1/18:1 were the main variables in Lipozyme TL IM and Novozym 435 enzyme-catalyzed products under different water content conditions. Finally, the fate of POA-TAG across the gastrointestinal tract was simulated using an in vitro digestion model. The results showed that the maximum release of free fatty acids and apparent rate constants were 71.44% and 0.0347 s-1, respectively, for POA-TAG lipids, and the physical and structural characteristics during digestion depended on their microenvironments. These findings provide a theoretical basis for studying the rational design of POA-structural lipids and exploring the nutritional and functional benefits of POA products.

Fish oil-loaded multicore submillimeter-sized capsules prepared with monoaxial electrospraying, chitosan-tripolyphosphate ionotropic gelation, and Tween blending.

In order to load fish oil for potential encapsulation of fat-soluble functional active substances, fish oil-loaded multicore submillimeter-sized capsules were prepared with a combination method of three strategies (monoaxial electrospraying, chitosan-tripolyphosphate ionotropic gelation, and Tween blending). The chitosan-tripolyphosphate/Tween (20, 40, 60, and 80) capsules had smaller and evener fish oil cores than the chitosan-tripolyphosphate capsules, which resulted from that Tween addition induced smaller and evener fish oil droplets in the emulsions. Tween addition decreased the water contents from 56.6 % to 35.0 %-43.4 %, increased the loading capacities from 10.4 % to 12.7 %-17.2 %, and increased encapsulation efficiencies from 97.4 % to 97.8 %-99.1 %. In addition, Tween addition also decreased the highest peroxide values from 417 meq/kg oil to 173-262 meq/kg oil. These properties' changes might result from the structural differences between the chitosan-tripolyphosphate and chitosan-tripolyphosphate/Tween capsules. All the results suggested that the obtained chitosan-tripolyphosphate/Tween capsules are promising carriers for fish oil encapsulation. This work also provided useful knowledge to understand the preparation, structural, and physicochemical properties of the chitosan-tripolyphosphate capsules.

Integrated Process for Schizochytrium Oil Extraction, Enzymatic Modification of Lipids and Concentration of DHA Fatty Acid Esters Using Alternative Methodologies.

Marine microalgae Schizochytrium sp. have a high content of docosahexaenoic acid (DHA), an omega-3 fatty acid that is attracting interest since it prevents certain neurodegenerative diseases. The obtention of a bioactive and purified DHA fatty acid ester using a whole-integrated process in which renewable sources and alternative methodologies are employed is the aim of this study. For this reason, lyophilized Schizochytrium biomass was used as an alternative to fish oil, and advanced extraction techniques as well as enzymatic modification were studied. Microalgal oil extraction was optimized via a surface-response method using pressurized liquid extraction (PLE) obtaining high oil yields (29.06 ± 0.12%) with a high concentration of DHA (51.15 ± 0.72%). Then, the enzymatic modification of Schizochytrium oil was developed by ethanolysis using immobilized Candida antarctica B lipase (Novozym® 435) at two reaction temperatures and different enzymatic loads. The best condition (40 °C and 200 mg of lipase) produced the highest yield of fatty acid ethyl ester (FAEE) (100%) after 8 h of a reaction attaining a cost-effective and alternative process. Finally, an enriched and purified fraction containing DHA-FAEE was obtained using open-column chromatography with a remarkably high concentration of 93.2 ± 1.3% DHA. The purified and bioactive molecules obtained in this study can be used as nutraceutical and active pharmaceutical intermediates of marine origin.

Molecular modification of low-dissolution soy protein isolates by anionic xanthan gum, neutral guar gum, or neutral konjac glucomannan to improve the protein dissolution and stabilize fish oil emulsion.

Herein, the effects of anionic xanthan gum (XG), neutral guar gum (GG), and neutral konjac glucomannan (KGM) on the dissolution, physicochemical properties, and emulsion stabilization ability of soy protein isolate (SPI)-polysaccharide conjugates were studied. The SPI-polysaccharide conjugates had better water dissolution than the insoluble SPI. Compared with SPI, SPI-polysaccharide conjugates had lower ß-sheet (39.6 %-56.4 % vs. 47.3 %) and α-helix (13.0 %-13.2 % vs. 22.6 %) percentages, and higher ß-turn (23.8 %-26.5 % vs. 11.0 %) percentages. The creaming stability of SPI-polysaccharide conjugate-stabilized fish oil-loaded emulsions mainly depended on polysaccharide type: SPI-XG (Creaming index: 0) > SPI-GG (Creaming index: 8.1 %-21.2 %) > SPI-KGM (18.1 %-40.4 %). In addition, it also depended on the SPI preparation concentrations, glycation times, and glycation pH. The modification by anionic XG induced no obvious emulsion creaming even after 14-day storage, which suggested that anionic polysaccharide might be the best polysaccharide to modify SPI for emulsion stabilization. This work provided useful information to modify insoluble proteins by polysaccharides for potential application.

Enzymatically produced acylglycerol and glycerin monostearate additives improved the characteristics of gelatin-stabilized omega-3 emulsions and microcapsules.

The impacts of enzymatically produced acylglycerol and glycerin monostearate on the characteristics of gelatin-stabilized omega-3 emulsions and microcapsules were investigated. Tuna oil was enzymatically produced and the resulting acylglycerol was mixed with tuna oil at 12.5% (w/w) to prepare a novel oil phase. This oil phase was stabilized by gelatin to prepare oil-in-water emulsions and subsequent microcapsules via complex coacervation. The tuna oil with glycerin monostearate (GMS) at 1 and 2% (w/w) were used as controls. Results showed that both acylglycerol and GMS significantly reduced the emulsion droplet size and zeta potential, while increasing the viscoelasticity and stability. The diacylglycerol/monoacylglycerol were involved in the oil/water interfacial layer formation by lowering interfacial tension and increasing droplet surface hydrophobicity. Overall, the changed emulsion properties promoted the complex coacervation and contributed to the formation of microcapsules with improved oxidative stability. Therefore, enzymatically produced acylglycerol can develop high-quality stable omega-3 microencapsulated novel food ingredients.

Molecular phylogenetics of the Umbelopsis genus-identification of new species and evaluation of their oil application value.

AIMS: The aim of this study was to reconstruct the evolutionary framework of the genus Umbelopsis by using modern taxonomic strategies and evaluating the quality of oil and prospective uses of three distinct species. METHODS AND RESULTS: Three species of Umbelopsis were identified based on morphological characteristics and phylogenetic evidence obtained from three genes (ITS, LSU, and ACT). A new species of Umbelopsis was described and illustrated, and subsequently named U. ophiocordycipiticola. The characteristics of U. ophiocordycipiticola exhibited sporangia with a diameter ranging from 8 to 17 µm. and sporangiospores that were oval to ellipsoidal in shape, irregularly angular, with dimensions of ∼1.9-2.9 × 1.7-3.0 µm. Gas chromatography and mass spectrometry (GC-MS) were used to examine the composition of fatty acids. Notably, U. ophiocordycipiticola showed a significantly higher oil content of 50.89% in dry cell weight (DCW) compared to U. vinacea and U. ramanniana. The mean proportion of polyunsaturated fatty acids (PUFAs) in U. ophiocordycipiticola was 32.38%, and the maximum levels of γ-linolenic acid (GLA), arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in U. ophiocordycipiticola were found to be 14.51, 0.24, 0.54, and 0.53%, respectively. The biodiesel quality from all three species complied with applicable standards set by the American Association for Testing and Materials (ASTM 6751) and the Brazilian National Petroleum Agency (ANP 255). CONCLUSIONS: The establishment of a novel species, U. ophiocordycipiticola, was strongly supported by morphological and molecular evidence. Umbelopsis ophiocordycipiticola exhibited a high-value PUFA content. Additionally, three Umbelopsis species demonstrated good quality for biodiesel production.

Inhibition performance of almond shell hydrochar-based fish oil emulsion gel on Klebsiella pneumonia inoculated fish skin and its characteristics.

In this study, the inhibition potential against Klebsiella pneumoniae (K. pneumoniae) and the characterization of fish oil (FO) emulsion gel (EGE) containing almond shell hydrochar (AH) were investigated. Oily water of mullet liver was emulsified using tween 80, then gelled using gelatin and finally immobilized into hydrochar using an ultrasonic homogenizer. Characteristics and surface analysis of hydrochar-based emulsion gel (HEGE) were examined using FTIR and SEM. Stability, particle size distribution and zeta potential of HEGE were measured. In this study, a zeta potential of -18.46 indicated that HEGE was more stable than EGE (35.7 mV). The addition of hydrochar to the emulsion gel containing micro-droplets enabled the structure to become fully layered and stable. Time-dependent inactivation of K. pneumoniae exposed to HEGE and fixed in 6 mm-fish skin was evaluated for the first time in this study. While the highest log reduction and percent reduction in the bacterial count were achieved within 5 min with 0.87 CFU/cm2 and 86.60% with EGE, the lowest log reduction and percent reduction were achieved with 0.003 CFU/cm2 and 0.082% with HEGE in 30 min. In conclusion, the almond shell hydrochar-immobilized emulsion gel is a functional adsorbent that can inhibit K. pneumonia, and its stability and performance make it a unique candidate for further studies in this field.

Subcritical water-assisted fish gelatin hydrolysis for astaxanthin-loaded fish oil emulsion stability.

Though gelatin emulsifying properties have been intensively studied, how low-molecular-weight (LMW) fish gelatin affects astaxanthin (AST)-loaded fish oil emulsion stability remains elusive. In this study, subcritical water hydrolysis (SWH)-modified LMW fish gelatin (SWHG) was produced from 110 °C to 180 °C and used to enhance the AST steadiness in oil/water emulsions in the presence of an emulsifier, lecithin. In the prepared emulsions, the surface charge increased while droplet size decreased with the decrease in gelatin MW due to the reduced thickness of the adsorbed gelatin membrane. LMW gelatin and lecithin could form a firm-absorbed layer on the droplet surface by electrostatic interaction between amide groups of gelatin molecules and phosphate groups of lecithin, thus stabilizing the emulsions. SWHG improved the creaming stability of the emulsions and hindered the oxygen- and light-induced AST degradation for 11 months compared to high MW gelatin. Whereas, the control emulsion showed noticeable phase separation after two weeks of storage. These findings prove the advantage of the SWH approach and propose the use of SWHG in oil-in-water emulsions for AST stabilization.

An Overview of Parenteral Nutrition from Birth to Adolescence Based on a Composite Fish Oil Containing Lipid Emulsion and a Pediatric Amino Acid Solution.

Intestinal failure (IF) is characterized by a critical reduction in functional gut mass below the minimum needed for optimal growth in children. It requires parenteral nutrition (PN) and home-PN (HPN), which is challenging in terms of meeting nutritional needs according to age, growth velocity, clinical situation, and rapid changes in fluid and electrolyte requirements. Due to these complex requirements, age-adapted multi-chamber bags (MCBs) are important additions to the nutrition armamentarium. The launch of composite fish oil (FO)-containing intravenous lipid emulsions (ILEs) heralded the development of MCBs containing these ILEs in combination with a crystalline amino acid solution adapted for pediatric use. The safety and efficacy of lipid and amino acid components in this context have been widely documented in numerous published studies. This narrative manuscript includes a review of the articles published in PudMed, Embase, and Google Scholar up to June 2023 for the age groups of term infants to children and adolescents. Preterm infants with their highly specific demands are not included. It aims to offer an overview of the clinical experience regarding the use of a composite FO-based ILE and a developed specific amino acid solution.

High-pressure microfluidization enhanced the stability of sodium caseinate-EGCG complex-stabilized fish oil emulsion.

Improving the emulsion-stabilizing effect of protein by chemical or physical modification has been paid much attention recently. Here, sodium caseinate (CS) was treated by high-pressure-microfluidization (HPM) under 0-100 MPa, and was further complexed with (-)-epigallocatechin-3-gallate (EGCG) to form an excellent emulsifier that stabilized fish oil emulsions. Results showed that HPM treatment (especially 80 MPa) significantly changed the secondary structure of CS, and 80 MPa-PCS-EGCG had the best emulsifying and antioxidant activities. In addition, after HPM treatment and EGCG bonding, CS formed a thicker interface layer on the surface of oil droplets, which could better protect the fish oil from the influence by oxygen, temperature and ion concentration. Moreover, the fish oil emulsion stabilized by PCS-EGCG complex significantly delayed the release of free fatty acids subjected to in vitro digestion. Conclusively, HPM-treated CS-EGCG complex could be a potential emulsifier to improve the stability of fish oil emulsions.

Combined cross-linking of Rhizomucor miehei lipase and Candida antarctica lipase B for the effective enrichment of omega-3 fatty acids in fish oil.

The incorporation of a non-specific lipase and a sn-1,3 specific one in a single immobilized system can be a promising approach for the exploitation of both lipases. A one-step immobilization platform mediated by an isocyanide-based multi-component reaction was applied to create co-cross-linked enzymes (co-CLEs) of lipases from Rhizomucor miehei (sn-1,3 specific) and Candida antarctica (non-specific). Glutaraldehyde was found to be effective cross-linker by producing specific activity of 16.9 U/mg and immobilization yield of 99 %. High activity recovery of up to 404 % was obtained for immobilized derivatives. Leaking experiment showed covalent nature of the cross-linking processes. BSA had considerable effect on the immobilization process, providing 87-100 % immobilization yields and up to 10 times improvement in the specific activity of the immobilized derivatives. Scanning electron microscopy images showed flower-like and rod-like structures for the CLEs prepared by glutaraldehyde and undecanedicarboxylic acid, respectively. The prepared co-CLEs were examined in non-selective enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil, showing capability of releasing up to 100 % of both omega-3 fatty acids within 8 h of the reaction. The reusability of co-CLEs in five successive cycles presented retaining 63-72 % of their initial activities after the fifth reuse cycle in the hydrolysis reaction.

Characterization of fatty acid forms using benchtop NMR in omega-3 oil supplements.

Omega-3 fatty acid supplements, such as fish oil and plant-based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega-3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega-3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega-3 fatty acids in dietary supplements, utilizing a 60-MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H-1H COSY NMR provides a quick and accurate approach to screen the forms of omega-3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user-friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega-3 supplements.

Fatty Acid Positions in Triacylglycerol of Iridescent Shark Fish Oil (Pangasius sp.), Focusing on Omega-3 and Omega-6 Fatty Acids.

<b>Background and Objective:</b> Considering the many health benefits of fish oil, the potential of Indonesian fisheries needs to be mapped to find local fish oil sources that have the opportunity to be used as a source of omega-3 and 6. This research aimed to ascertain the glyceride profile of iridescent shark fish oil hydrolyzed by immobilized lipase from <i>Thermomyces lanuginosus</i> at the sn-1,3 position and identify the position of omega-3 and omega-6 fatty acids. <b>Materials and Methods:</b> To extract the fish oil from the iridescent shark, the soxhletation method was utilized. The analysis of the fatty acid composition that was carried out using gas chromatography (GC) was previously esterified with BF₃ before it was carried out to position the fatty acid hydrolysis that was carried out using lipase enzymes to position the fatty acid composition. <b>Results:</b> The sample had more unsaturated fatty acids than saturated ones. Omega-3 and omega-6 fatty acids are more concentrated in the fat molecule's sn-2 position than in the sn-1+sn-3 location. Iridescent shark fish oil meets the recommended ratio of omega-3 to omega-6 (1:1) or better (2:1). <b>Conclusion:</b> It has been discovered that iridescent shark fish oil is rich in omega-3 and omega-6 fatty acids, especially those in the sn-2 position. This makes it a great food choice for those trying to get more omega-3 unsaturated fatty acids into their diets.

Application of Chromatographic and Spectroscopic-Based Methods for Analysis of Omega-3 (ω-3 FAs) and Omega-6 (ω-6 FAs) Fatty Acids in Marine Natural Products.

Omega-3 fatty acids v(ω-3 FAs) such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) and omega-6 fatty acids (ω-6 FAs) such as linoleic acid and arachidonic acid are important fatty acids responsible for positive effects on human health. The main sources of ω-3 FAs and ω-6 FAs are marine-based products, especially fish oils. Some food, supplements, and pharmaceutical products would include fish oils as a source of ω-3 FAs and ω-6 FAs; therefore, the quality assurance of these products is highly required. Some analytical methods mainly based on spectroscopic and chromatographic techniques have been reported. Molecular spectroscopy such as Infrared and Raman parallel to chemometrics has been successfully applied for quantitative analysis of individual and total ω-3 FAs and ω-6 FAs. This spectroscopic technique is typically applied as the alternative method to official methods applying chromatographic methods. Due to the capability to provide the separation of ω-3 FAs and ω-6 FAs from other components in the products, gas and liquid chromatography along with sophisticated detectors such as mass spectrometers are ideal analytical methods offering sensitive and specific results that are suitable for routine quality control.

Hyaluronic Acid Poly(glyceryl)10-Stearate Derivatives: Novel Emulsifiers for Improving the Gastrointestinal Stability and Bioaccessibility of Coenzyme Q10 Nanoemulsions.

Fish oils are a rich source of polyunsaturated fatty acids, including eicosapentaenoic acid and docosahexaenoic acid, which are reported to exhibit therapeutic effects in a variety of human diseases. However, these oils are highly susceptible to degradation due to oxidation, leading to rancidity and the formation of potentially toxic reaction products. The aim of this study was to synthesize a novel emulsifier (HA-PG10-C18) by esterifying hyaluronic acid with poly(glyceryl)10-stearate (PG10-C18). This emulsifier was then used to formulate nanoemulsion-based delivery systems to co-deliver fish oil and coenzyme Q10 (Q10). Q10-loaded fish oil-in-water nanoemulsions were fabricated, and then their physicochemical properties, digestibility, and bioaccessibility were measured. The results indicated that the environmental stability and antioxidant activity of oil droplets coated with HA-PG10-C18 surpassed those coated with PG10-C18 due to the formation of a denser interfacial layer that blocked metal ions, oxygen, and lipase. Meanwhile, the lipid digestibility and Q10 bioaccessibility of nanoemulsions formulated with HA-PG10-C18 (94.9 and 69.2%) were higher than those formulated with PG10-C18 (86.2 and 57.8%), respectively. These results demonstrated that the novel emulsifier synthesized in this study could be used to protect chemically labile fat-soluble substances from oxidative damage, while still retaining their nutritional value.

In parenteral nutrition-fed piglets, fatty acids vary by lipid emulsion and tissue sampled.

BACKGROUND: Children with intestinal failure without liver disease may be given soy-based lipid emulsion (SLE) or mixed lipid emulsion (MLE; containing soy, medium-chain triglyceride, olive, and/or fish oils). Both differ in essential fatty acid content: MLE has added arachidonic acid (AA) and docosahexaenoic acid (DHA). The aim of this study, in neonatal piglets, was to compare serum and tissue fatty acid composition when the emulsions were given at unrestricted doses. METHODS: We compared SLE (n = 15) and MLE (n = 15) at doses of 10-15 g/kg/day in parenteral nutrition (PN). On day 14 we collected serum and tissues. Using gas-liquid chromatography, percentage fatty acids were measured in serum, brain, and liver phospholipid. Comparisons were made to reference values from litter-matched controls (n = 8). RESULTS: Comparing median values, linoleic acid (LA) was lower for MLE vs SLE in serum (-27%), liver (-45%), and brain (-33%) (P < 0.001). AA was lower for MLE in serum (-25%), liver (-40%), and brain (-10%). DHA was higher for MLE in serum (+50%), liver (+200%), and brain (+10%). AA levels were lower for MLE vs control piglets in serum (-81%), liver (-63%), and brain (-9%). DHA levels were higher in serum (+41%), liver (+38%), and brain (+19%). CONCLUSION: This study in piglets has shown that, at unrestricted doses, MLE treatment is associated with low serum and tissue AA compared with SLE and healthy litter-matched controls. Although not yet proven, low tissue AA levels may have functional consequences, and these data support current practice avoiding MLE dose restriction.

Effects of activated earth, activated alumina, and chitosan adsorption processes on thermal and rheological and chemical characteristics of menhaden oil.

The objective of this study was the effectiveness of using activated earth, activated alumina, and/or chitosan, either separately or in combination, as adsorbents to remove free fatty acids (FFA) and peroxides from unpurified menhaden oil (MO). Thermal and rheological properties of MO were also evaluated. Five different combinations of absorbents were used to purify MO: Processes 1-3 involved purifications of MO by 5% chitosan (wt/wt of oil), 5% activated earth, and 5% activated alumina, respectively, process 4 involved MO purification with a combination of 6.5% chitosan, 3.5% activated earth, and 5% activated alumina, and process 5 involved MO purification process with a combination of adsorbents of 9% chitosan, 1% activated earth, and 5% activated alumina. All the adsorption processes were conducted at 25°C. Purified MO and MO were evaluated for their fatty acid profile, FFA, peroxide value (PV), moisture content (MC), minerals, and color. Triplicate experiments were conducted, and data were statistically analyzed using α = 0.05. Processes 4 and 5 were effective in reducing PV, FFA, and MC in MO. Thermal properties indicated processes 4 and 5 produced purer MO than processes 1-3. All the oil samples became less viscous, and the flow behavior index of MO was close to 1 after the adsorption processes. This study demonstrated that adsorption processes that include chitosan, activated earth, and activated alumina could effectively improve MO quality.

Analysis of fatty acid composition and sensitivity to dietary n-3 PUFA intervention of mouse n-3 PUFA-enriched tissues/organs.

PURPOSE: n-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA; C22:6 n3) and eicosapentaenoic acid (EPA; C20:5 n3), are of concern for their health-promoting effects such as anti-inflammatory, but the tissue selectivity for n-3 PUFA (i.e., which tissues and organs are rich in n-3 PUFA) is still not well known. In addition, it is unclear which tissues and organs are more sensitive to n-3 PUFA intervention. These unresolved issues have greatly hindered the exploring of the health benefits of n-3 PUFA. METHODS: Twenty-four 7-week-old male C57BL/6 J mice were assigned to the control, fish oil, DHA, and EPA groups. The last three groups were given a 4-week oral intervention of fatty acids in ethyl ester (400 mg/kg bw). The fatty acid profiles in 27 compartments were determined by gas chromatography. RESULTS: The proportion of long-chain n-3 PUFA (the total relative percentage of EPA, DPA n3, and DHA) was analyzed. Eight tissues and organs, including the brain (cerebral cortex, hippocampus, hypothalamus) and peripheral organs (tongue, quadriceps, gastrocnemius, kidney, and heart) were determined as being n-3 PUFA-enriched tissues and organs, owing to their high n-3 PUFA levels. The highest n-3 PUFA content was observed in the tongue for the first time. Notably, the content of linoleic acid (LA; C18:2 n6c) in peripheral organs was observed to be relatively high compared with that in the brain. Interestingly, the proportions of EPA in the kidney, heart, quadriceps, gastrocnemius, and tongue increased more markedly after the EPA intervention than after the DHA or fish oil intervention. As expected, the levels of proinflammatory arachidonic acid (AA; C20:4 n6) in the kidney, quadriceps, and tongue were markedly decreased after the three dietary interventions. CONCLUSION: Peripheral tissues and organs, including the tongue, quadriceps, gastrocnemius, kidney, and heart, besides the brain, showed obvious tissue selectivity for n-3 PUFA. In the whole body of mice, the tongue exhibits the strongest preference for n-3 PUFA, with the highest proportion of n-3 PUFA. Moreover, these peripheral tissues and organs, especially the kidney, are more sensitive to dietary EPA administration in comparison with the brain.

Circulating polyunsaturated fatty acids, fish oil supplementation, and risk of incident dementia: a prospective cohort study of 440,750 participants.

Cohort studies report inconsistent associations between omega-3 polyunsaturated fatty acids (n-3 PUFA) or fish oil and dementia risk. Furthermore, evidence relating omega-6 polyunsaturated fatty acids (n-6 PUFA) with dementia is scarce. Here, we included 440,750 dementia-free participants from UK Biobank to comprehensively investigate the associations between plasma levels of different types of PUFA, fish oil supplementation, and dementia risk. During a median follow-up of 9.25 years, 7768 incident dementia events occurred. Higher plasma levels of five PUFA measures showed consistent associations with lower dementia risk (hazard ratios [95% confidence intervals] for per standard deviation increment of plasma concentrations 0.85 [0.81-0.89] for total PUFAs; 0.90 [0.86-0.95] for omega-3 PUFAs; 0.92 [0.87-0.96] for docosahexaenoic acid (DHA); 0.86 [0.82-0.90] for omega-6 PUFAs; 0.86 [0.82-0.90] for linoleic acid (LA); all p < 0.001). Compared with non-users, fish oil supplement users had a 7% decreased risk of developing all-cause dementia (0.93 [0.89-0.97], p = 0.002), and the relationship was partially mediated by plasma n-3 PUFA levels (omega-3 PUFAs: proportion of mediation = 57.99%; DHA: proportion of mediation = 56.95%). Furthermore, we observed significant associations of plasma n-3 PUFA levels and fish oil supplementation with peripheral immune markers that were related to dementia risk, as well as the positive associations of plasma PUFA levels with brain gray matter volumes and white matter microstructural integrity, suggesting they may affect dementia risk by affecting peripheral immunity and brain structure. Taken together, higher plasma PUFA levels and fish oil supplementation were associated with lower risk of incident dementia. This study may support the value of interventions to target PUFAs (specifically n-3 PUFAs) to prevent dementia.

Effect of a parenteral fish-oil-containing lipid emulsion on liver lipid perioxidation and antioxidative defenses in Lewis rats.

BACKGROUND: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), naturally abundant in fish oil (FO), are known for their anti-inflammatory and potential antioxidant properties. The aim in this article is to evaluate the effect of the infusion of a parenteral FO-containing lipid emulsion on markers of liver lipid peroxidation and oxidative stress in rats undergoing central venous catheterization (CVC). METHODS: After 5-day acclimatization, adult Lewis rats (n = 42) receiving a 20-g/day AIN-93M oral diet were randomly subdivided into four groups: (1) basal control (BC) (n = 6), without CVC or LE infusion; (2) SHAM (n = 12), with CVC but without LE infusion; (3) soybean oil (SO)/medium-chain triglyceride (MCT) (n = 12), with CVC and receiving LE without FO (4.3 g/kg fat); and (4) SO/MCT/FO (n = 12), with CVC and receiving LE containing 10% FO (4.3 g/kg fat). Animals from the BC group were euthanized immediately after acclimatization. The remaining groups of animals were euthanized after 48 or 72 h of surgical follow-up to assess profiles of liver and plasma fatty acids by gas chromatography, liver gene transcription factor Nrf2, F2-isoprostane lipid peroxidation biomarker, and the antioxidant enzymes glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) by enzyme-linked immunosorbent assay. R program (version 3.2.2) was utilized for data analysis. RESULTS: Compared with the other groups, liver EPA and DHA levels were higher in the SO/MCT/FO group, which also showed the highest liver Nrf2, GPx, SOD, and CAT levels and lower liver F2-isoprostane (P < 0.05). CONCLUSION: Experimental delivery of FO via EPA and DHA sources in a parenteral LE was associated with a liver antioxidant effect.