Blood EPA and DHA status among people living in the United States from 2000 to 2023.

Long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs), specifically eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3), are well-known for their various health benefits, including cardiovascular and cognitive health. In this study we explored the EPA+DHA blood status across different states within the United States. A widely used marker to assess the EPA+DHA status is the omega-3 index - defined as the % of EPA+DHA in red blood cells (RBC) in relation to total fatty acids. A systematic literature search was conducted for US-studies from 2000 until October 2023 reporting EPA+DHA blood values. Further inclusion criteria were: information in which US state the study was carried out, no pregnant women, at least 16 years of age. A total of 46 studies met all inclusion criteria. EPA+DHA levels from studies utilizing blood metrics other than RBC were converted to an estimated RBC EPA+DHA (eRBC EPA+DHA) status marker using established conversion equations. The mean eRBC EPA+DHA across the US was 5.28% and, is in line with previous investigations. Most US states showed an average eRBC EPA+DHA in the range 4.50% to 5.50%. Furthermore, we found that coastal states tend to have higher eRBC EPA+DHA (5.26%) than inland states (4.86%). This is consistent with the slightly higher fish consumption in coastal states compared to inland states. The data from the studies included in the evaluation show that the blood status of EPA+DHA is suboptimal. The supply of EPA and DHA should be improved, especially in inland states. Further research is needed to better monitor EPA+DHA status in the US. Since the EPA+DHA blood status is a modifiable risk factor for many diseases, public health officials should take steps to emphasize the significance of n-3 PUFAs in preserving the health of the US population.

The effect of fish oil rich in cetoleic acid on the omega-3 index and skin quality.

OBJECTIVE: The objective of the study was to provide preliminary data on the effect of a long chain monounsaturated oil rich in cetoleic acid on the omega-3 index, a validated measure of EPA and DHA in blood cells, as well as a potential effect of the oil on skin quality. DESIGN: Two intervention studies were performed, each as double blinded, placebo controlled, randomised nutritional trials. The CetoIndex study (N = 55) measured omega-3 index using a blood spot collection kit (Omegaquant). The Optihud study (N = 28) measured skin quality parameters in healthy women using the VISIA system. The cetoleic-rich-oil (CRO) was an oil derived from North Atlantic fish with a predominance of long chain mono-unsaturated fatty acids including cetoleic acid (C22:1 n-11) and gondoic acid (C20:1 n-9). RESULTS: In a placebo-controlled study, the omega-3 index in healthy volunteers was increased similar to that seen with an oil with higher levels of omega-3 fatty acids. In a separate placebo-controlled study, the CRO reduced erythema in skin, which is a marker of inflammation. CONCLUSIONS: The results of this pilot study suggest that the use of a CRO increases the omega-3 index more than expected from the levels of EPA and DHA in the oil. The CRO may potentially have benefits on skin inflammation. SUMMARY: Long chain polyunsaturated fatty acids (LCPUFA), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are commonly taken as dietary supplements for a range of health benefits. Other marine fatty acids may also provide health benefits and it is of interest to understand their activity. Long chain mono-unsaturated fatty acids (LCMUFA) have shown biological activity in studies of metabolic health in animal models. Here, we report two intervention studies using a fish oil with a high LCMUFA content where cetoleic acid is the predominant fatty acid (Cetoleic rich oil: CRO). In CetoIndex, a placebo-controlled study in 55 healthy volunteers, the omega-3 index increased similarly to that seen with an oil containing higher levels of omega-3 fatty acids. In Optihud, a placebo-controlled study in 28 female volunteers, the CRO reduced erythema in skin, which is a marker of inflammation. The results of this pilot study support the use of a CRO for increasing the omega-3 index with potential benefits on skin inflammation.

n-3 PUFAs Show Promise as Adjuvants in Chemotherapy, Enhancing their Efficacy while Safeguarding Hematopoiesis and Promoting Bone Generation.

Cancer ranks as the second leading cause of mortality in high-income countries, underscoring the critical need for effective therapeutic strategies. One prominent approach, chemotherapy, is widely employed for treating solid tumors. However, the significant adverse effects associated with chemotherapy, notably myeloablation and osteonecrosis, impart considerable challenges by compromising immune function and diminishing patients' quality of life. Furthermore, the emergence of chemotherapy resistance poses a formidable hurdle in achieving successful cancer treatment outcomes. In this context, the focus is on exploring alternative approaches to enhance the efficacy of cancer treatment and mitigate its adverse consequences. Among these approaches, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), two n-3 polyunsaturated fatty acids (PUFAs), have garnered substantial interest. These PUFAs exhibit the potential to influence membrane lipid composition and modulate critical gene expressions associated with cancer, such as Bcl-2, PI3K, NF-κB, and phosphorylated Akt, thereby potentially reducing cancer risk. Moreover, emerging evidence highlights their ability to augment chemotherapy efficacy, particularly in drug-resistant cancer cells. Importantly, both preclinical and clinical investigations have provided compelling evidence supporting the protective effects of n-3 PUFAs on healthy cells. Leveraging these findings, there has been growing attention on the exploration of n-3 PUFAs as adjuvants to chemotherapy. This strategic approach holds promise in mitigating the adverse effects linked to chemotherapy, notably myeloablation and osteonecrosis, while simultaneously enhancing its effectiveness in combating cancer. This comprehensive review delves into the multifaceted attributes of n-3 PUFAs, encompassing their cytotoxic properties, potential as chemopreventive agents, and their prospective role in ameliorating the adverse effects commonly associated with chemotherapy, with a particular emphasis on myeloablation and osteonecrosis. By elucidating the intricate interplay between n-3 PUFAs and cancer treatment paradigms, this review contributes to the expanding body of knowledge aimed at refining cancer therapeutic strategies and enhancing patient outcomes.

Hexachlorobenzene and omega-3 fatty acid intake from traditional foods in the northern Yukon: A risk and benefit analysis.

A human biomonitoring study was conducted in the community of Old Crow, Yukon, in 2019, finding that levels of hexachlorobenzene (HCB) in plasma were elevated in the community relative to the general Canadian population. The aim of this study was to estimate dietary intake of both hexachlorobenzene, and the nutrient omega-3 fatty acids from locally harvested traditional foods in Old Crow, with the aim of identifying possible regional sources of exposure. A stochastic model was constructed to estimate intake of both hexachlorobenzene and the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Average predicted hexachlorobenzene exposure levels from traditional food consumption in Old Crow were below the tolerable daily intake of 1600-1700 ng/kg body weight/day in both average (18 ng/kg body weight/day) and short-term maximum (27 ng/kg body weight/day) exposure models. The primary contributors to average hexachlorobenzene intake were caribou fat, bone marrow, ribs, and kidneys, and Chinook salmon muscle. Average estimated dietary EPA + DHA intake levels from traditional foods were below the recommendation of 2.1 to 3.2 g of EPA + DHA per week in the average (1.6 g/week) exposure model, but above this recommendation in the short-term maximum model (3.3 g/week). The primary contributors to average EPA + DHA intake were the meat of Chinook, coho, and, chum salmon muscle, and whitefish muscle and eggs. The results of this study support the message that traditional foods continue to be an important source of nutrients and other health benefits and that the health benefits of traditional foods generally outweigh contaminant risks.

DHA/EPA (Omega-3) and LA/GLA (Omega-6) as Bioactive Molecules in Neurodegenerative Diseases.

Neurodegenerative diseases are characterized by neuroinflammation, neuronal depletion and oxidative stress. They coincide with subtle chronic or flaring inflammation, sometimes escalating with infiltrations of the immune system cells in the inflamed parts causing mild to severe or even lethal damage. Thus, neurodegenerative diseases show all features of autoimmune diseases. Prevalence of neurodegenerative diseases has dramatically increased in recent decades and unfortunately, the therapeutic efficacy and safety profile of available drugs is moderate. The beneficial effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) polyunsaturated fatty acids (omega-3 PUFAs) are nowadays highlighted by a plethora of studies. They play a role in suppression of inflammation, gene expression, cellular membrane fluidity/permeability, immune functionality and intracellular/exocellular signaling. The role of omega-6 polyunsaturated fatty acids, such as linoleic acid (LA), gamma linolenic acid (GLA), and arachidonic acid (AA), on neuroprotection is controversial, as some of these agents, specifically AA, are proinflammatory, whilst current data suggest that they may have neuroprotective properties as well. This review provides an overview of the existing recent clinical studies with respect to the role of omega-3 and omega-6 PUFAs as therapeutic agents in chronic, inflammatory, autoimmune neurodegenerative diseases as well as the dosages and the period used for testing.

Comprehensive Screening for EPA/DHA-Structured Phospholipids in Aquatic Products by a Specific Precursor Ion Scanning-Based HILIC-MS/MS Method.

Comprehensive screening for functional substances from natural resources is always a hot research topic. Eicosapentaenoic acid- (EPA) and docosahexaenoic acid (DHA)-structured phospholipids (PLEPA/DHA) have versatile cardiovascular benefits as well as superior bioavailability. Herein, the abundance of PLEPA/DHA in 16 aquatic products was specifically and selectively screened using a recently developed precursor ion scan-driven hydrophilic interaction chromatography-mass spectrometry (PreIS-HILIC/MS) method with the fatty acyl moieties of EPA (m/z 301.6) and DHA (m/z 327.6) locked. The aim focused on the characteristics and differences in the varieties and contents of EPA/DHA-structured phosphatidylcholine (PCEPA/DHA) and EPA/DHA-structured phosphatidylethanolamine (PEEPA/DHA) molecular species. A total of 80 PLEPA/DHA molecules were identified in these natural sources, including 47 PCEPA/DHA and 33 PEEPA/DHA. After analysis, PC 16:0/20:5 and PC 16:0/22:6 are present in all aquatic products and at high levels. Antarctic krill was found to be the best resource of PLEPA/DHA in total (2574.69 µg·g-1), followed by mackerel (2330.11 µg·g-1), salmon (2109.91 µg·g-1), and Farrer's scallop (1883.59 µg·g-1), while abalone contained the lowest level of PLEPA/DHA (310.44 µg·g-1). Besides, sea cucumber and sea bass contained the highest contents of EPA-structured and DHA-structured ether phospholipids, respectively, which could be highly recommended as dietary sources of special functional phospholipids. Finally, the multiple discrepancies between the 16 aquatic products were revealed by multivariate statistical analysis. These findings improve the awareness of the composition and content of PLEPA/DHA contained in aquatic products, providing a reference for their integrated development.

Long-chain n-3 PUFA given before and throughout gestation and lactation in rats prevent high-fat diet-induced insulin resistance in male offspring in a tissue-specific manner.

This study investigated whether long-chain n-3 PUFA (LC n-3 PUFA) given to pregnant rats fed a high-fat (HF) diet may prevent fetal programming in male offspring at adulthood. Six weeks before mating, and throughout gestation and lactation, female nulliparous Sprague-Dawley rats were given a chow (C) diet, HF (60·6 % fat from maize, rapeseed oils and lard) or HF in which one-third of fat was replaced by fish oil (HF n-3). At weaning, the three offspring groups were randomly separated in two groups fed C diet, or HF without LC n-3 PUFA, for 7 weeks until adulthood. Glucose tolerance and insulin sensitivity were assessed by an oral glucose tolerance test both at weaning and at adulthood. Insulin signalling was determined in liver, muscle and adipose tissue by quantification of the phosphorylation of Akt on Ser 473 at adulthood. At weaning, as at adulthood, offspring from HF-fed dams were obese and displayed glucose intolerance (GI) and insulin resistance (IR), but not those from HFn-3 fed dams. Following the post-weaning C diet, phosphorylation of Akt was strongly reduced in all tissues of offspring from HF dams, but to a lesser extent in liver and muscle of offspring from HFn-3 dams. However, it was abolished in all tissues of all offspring groups fed the HF post-weaning diet. Thus, LC n-3 PUFA introduced in a HF in dams partially prevented the transmission of GI and IR in adult offspring even though they were fed without LC n-3 PUFA from weaning.

Selenium nanoparticles and omega-3 fatty acid enhanced thermal tolerance in fish against arsenic and high temperature.

The aquatic ecosystem is prone to global climate change and pollution affecting aquatic animals, including fish. In light of the above, we experimented with delineate the role of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with selenium nanoparticles (Se-NPs) to enhance the thermal tolerance in Pangasianodon hypophthalmus reared under control or concurrent exposure to high temperature and arsenic (As + T) for 112 days. Se-NPs were synthesized using the green approach. Four experimental diets viz. EPA + DHA at 0.2, 0.4 and 0.6 % along with Se-NPs at 0.2 mg kg-1 diet were formulated and prepared. End of the experiment (112 days), the thermal tolerance viz. CTmin (critical thermal minima) CTmax (critical thermal maxima), LTmin (lethal thermal minima) and LTmax (lethal thermal maxima) were determined. Supplementation of EPA + DHA along with Se-NPs noticeably improved the thermal tolerance of the fish reared under stress (As + T) and control condition. Superoxide dismutase, glutathione-s-transferase, catalase, glutathione peroxides and LPO were enhanced by As + T, whereas EPA + DHA at 0.4 % and Se-NPs reduced the oxidative stress. Further, acetylcholine esterase was inhibited by arsenic alone and concurrent with temperature but dietary supplementation significantly enhanced the brain AChE activity. Exposure to arsenic and concurrent with a temperature significantly reduced the ATPase. Whereas supplementation of EPA + DHA at 0.4 % and Se-NPs enhanced the ATPase in liver and gill tissues. Arsenic bioaccumulation was also reduced with EPA + DHA at 0.4 % and Se-NPs. The present investigation concluded that EPA + DHA at 0.4 % and Se-NPs at 0.2 mg kg-1 diet protects the P. hypophthalmus against arsenic pollution and thermal stress.

Influence of Nutritional Intakes in Japan and the United States on COVID-19 Infection.

The U.S. and Japan are both democratic industrialized societies, but the numbers of COVID-19 cases and deaths per million people in the U.S. (including Japanese Americans) are 12.1-times and 17.4-times higher, respectively, than those in Japan. The aim of this study was to investigate the effects of diet on preventing COVID-19 infection. An analysis of dietary intake and the prevalence of obesity in the populations of both countries was performed, and their effects on COVID-19 infection were examined. Approximately 1.5-times more saturated fat and less eicosapentaenoic acid/docosahexaenoic acid are consumed in the U.S. than in Japan. Compared with food intakes in Japan (100%), those in the U.S. were as follows: beef 396%, sugar and sweeteners 235%, fish 44.3%, rice 11.5%, soybeans 0.5%, and tea 54.7%. The last four of these foods contain functional substances that prevent COVID-19. The prevalence of obesity is 7.4- and 10-times greater in the U.S. than in Japan for males and females, respectively. Mendelian randomization established a causal relationship between obesity and COVID-19 infection. Large differences in nutrient intakes and the prevalence of obesity, but not racial differences, may be partly responsible for differences in the incidence and mortality of COVID-19 between the U.S. and Japan.

Long-chain Omega-3 fatty acids supplementation and cognitive performance throughout adulthood: A 6-month randomized controlled trial.

OBJECTIVE: To investigate whether omega-3 polyunsaturated fatty acids (n-3 PUFA) supplementation improve cognitive performance and if apolipoprotein E (APOE) genotype or age were effect modifiers. METHODS: Healthy adults of 20 to 80 years old (n = 193) were completed a 6-month double-blind randomized controlled trial with two groups: 2.5 g/day of n-3 PUFA or a placebo. Primary outcomes were visuospatial ability and working memory and secondary outcomes were episodic memory and executive function, measured at baseline and 6 months. RESULTS: Cognitive performances did not significantly differ between groups on primary or secondary outcomes after 6 months of treatment. APOE carriers and age were not effect modifiers for any outcomes. Those with low episodic memory scores and taking the n-3 PUFA supplement, significantly improved their scores (p = 0.043). CONCLUSIONS: A 6-month n-3 PUFA supplementation did not improve cognitive performance in cognitively healthy adults and APOE status or age were not effect modifiers.

From pond to table: Differences in breeding and consumption affect the balance between dietary risk of residual cadmium and uptake benefits of nutrients in Chinese mitten crab (Eriocheir sinensis).

We used a risk-benefit model to evaluate the effects of different farming methods and consumption habits on dietary risk of Chinese mitten crab. In this study, we found that cadmium levels in the total edible parts and brown meat were 0.029-0.462 mg/kg and 0.017-1.694 mg/kg, respectively. Cadmium exposure experiment showed that brown meat was the main enrichment site of cadmium. Fatty acid test found that the EPA + DHA content in total edible parts fed with formulated feed and iced trash fish was 19.64 ± 3.62 mg/g and 28.72 ± 2.30 mg/g (p > 0.05), respectively, and that in brown meat was 27.66 ± 5.16 mg/g and 40.15 ± 3.50 mg/g (p > 0.05), respectively. According to the risk-benefit model analysis, the dietary risk of brown meat under the two breeding methods is relatively high, but the risk quotient is less than 1.

Fast and Specific Screening of EPA/DHA-Enriched Phospholipids in Fish Oil Extracted from Different Species by HILIC-MS.

Eicosapentaenoic acid- and docosahexaenoic acid-enriched phospholipids (PLEPA/DHA) have versatile health-beneficial functions and can be well absorbed in the intestine. Herein, a precursor ion scan-driven hydrophilic interaction chromatography mass spectrometry (PreIS-HILIC-MS) method with the fatty acyl moieties of m/z 301.6 and 327.6 locked was established to specifically and selectively screen PLEPA/DHA in different fish oil samples, including saury, grass carp, hairtail, and yellow croaker. Taking saury oil as an example, a total of 24 PLEPA/DHA were successfully identified and quantified, including 20 PCEPA/DHA and 4 PEEPA/DHA. Finally, this method was validated in terms of sensitivity (limit of detection ≤ 4.15 µg·mL-1), linearity (≥0.9979), precision (RSDintraday ≤ 4.65%), and recovery (≥78.6%). The performance of the PreIS-HILIC-MS method was also compared with that of the traditional full-scan mode, and the former demonstrated its unique superiority in targeted screening of PLEPA/DHA in fish oils.

Synthesis of EPA- and DHA-Enriched Structured Acylglycerols at the sn-2 Position Starting from Commercial Salmon Oil by Enzymatic Lipase Catalysis under Supercritical Conditions.

There is consistent evidence that long-chain polyunsaturated fatty acids (LCPUFA) belonging to the n-3 series, i.e., eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic (22:6n-3, DHA) acids, decrease the risk of heart, circulatory and inflammatory diseases. Furthermore, the bioavailability of such fatty acids has been shown to depend on their location in triacylglycerol (TG) molecules at the sn-2 position. Consequently, great attention has been accorded to the synthesis of structured acylglycerols (sAG), which include EPA or DHA at the sn-2 position. The aim of this work was to synthesize sAG starting from deodorized refined commercial salmon oil. For this, immobilized lipase B from Candida antarctica (nonspecific) was used as a catalyst for the intra-interesterification process under CO2 supercritical conditions (CO2SC). According to the CO2SC reaction time, three different fractions including sAG compounds were obtained. The location of EPA and DHA at the sn-2 position in the resulting glycerol backbone was identified by mass spectrometry (MALDI-TOF) analysis. In all fractions obtained, a marked decrease in the starting TG content was observed, while an increase in the DHA content at the sn-2 position was detected. The fraction obtained after the longest reaction time period (2 h) led to the highest yield of sn-2 position DHA in the resulting sAG molecule.

Microalgae Oil as an Effective Alternative Source of EPA and DHA for Gilthead Seabream (Sparus aurata) Aquaculture.

Microalgal oils (AOs) emerged recently as an alternative to fish oil and to nutritionally poorer vegetable oils for fish species. In this trial, two experimental diets containing fish oil (negative control: 2.1%; positive control: 13.8%) and two diets incorporating AO at 3.5 and 0.7% were fed to grow out gilthead seabream (Sparus aurata) of 64.5 g initial body weight. After 110 days of experimental feeding, performance (final body weight mean = 147 g) and survival (>99%) were similar across treatments. The highest eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) content in positive control (PC) and 3.5 AO feeds (3.11 and 2.18% of diet, respectively) resulted in the highest EPA + DHA deposition in the fillets (18.40 and 12.36 g/100 g fatty acid, respectively), which entirely reflected the dietary fatty acid profile. Feed and fillets from fish fed the AO diets had lower levels of dioxins and polychlorinated biphenyls (PCBs). Moreover, sensory quality of AO fillets scored equally to the PC fish. Collectively, these findings offer a more resilient means for sustaining the future growth of seabream aquaculture, whilst maintaining the nutritional value of the resulting seafood. The data supports the addition of seabream to the list of aquaculture species where microalgal oil can be used as an ingredient to fulfil their challenging nutritional demands.

Enrichment of NaCl-reduced burger with long-chain polyunsaturated fatty acids: Effects on physicochemical, technological, nutritional, and sensory characteristics.

This study aimed to determine the effect of NaCl reduction and addition of long-chain polyunsaturated fatty acids (PUFA) on the quality traits of burgers. Fish oil was either directly incorporated or added as encapsulated by freeze-dried microparticles (complex coacervates) composed of soy protein isolate and inulin. Despite the differences in some parameters associated with NaCl reduction (e.g., instrumental hardness), the quality of the burgers was mainly affected by the microparticles. Thus, a decrease in pH and increase in hardness and chewiness were observed, and a higher exposure of fish oil to oxidation was observed thus increasing volatile oxidation compounds and negatively impacting on the sensory profile and overall liking of the burgers. However, the encapsulation of the fish oil helped to retain EPA and DHA after cooking. The results of the NaCl-reduced burger with unencapsulated fish oil suggest the possibility of incorporating PUFAs, but only containing EPA after cooking.

Enriched Fresh Pasta with a Sea Bass By-Product, a Novel Food: Fatty Acid Stability and Sensory Properties throughout Shelf Life.

A by-product from the filleting of sea bass (Dicentrachus labrax) was used to manufacture enriched pasta. The research aimed at achieving an increase of protein and unsaturated fatty acid contents, making innovative and healthy pasta products that are able to step up fish consumption. Two different kind of cereals were used to make fresh pasta, which were subjected to frozen storage with the addition or not of a rosemary antioxidant. The developed pastas were analyzed by physicochemical methods. Proximal analysis demonstrated an improvement of nutritional values on those of a common pasta. Fatty acid profiles, acidity indices, and TBARS (Thiobarbituric acid reactive substances) index confirmed the stability of fat and effective protection against oxidation, especially in pasta with added antioxidant. The cooking time for pasta was set at 90 s, and color parameters were modified due to the incorporation of fish in the pasta-making process. An enrichment in fatty acids ω-3 and ω-6 was also confirmed. The conversion of α-linolenic acid (ALA) in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in frozen storage was detected, which remained stable during 90 days. Finally, sensory profiles of enriched pasta were found to be adequate and improved following the addition of an antioxidant due to a decrease of negative attributes associated with oxidation.

Influence of Dietary Long-Chain Polyunsaturated Fatty Acids and ω6 to ω3 Ratios on Head Kidney Lipid Composition and Expression of Fatty Acid and Eicosanoid Metabolism Genes in Atlantic Salmon (Salmo salar).

The interaction of dietary eicosapentaenoic acid and docosahexaenoic acid (EPA+DHA) levels with omega-6 to omega-3 ratios (ω6:ω3), and their impact on head kidney lipid metabolism in farmed fish, are not fully elucidated. We investigated the influence of five plant-based diets (12-week exposure) with varying EPA+DHA levels (0.3, 1.0, or 1.4%) and ω6:ω3 (high ω6, high ω3, or balanced) on tissue lipid composition, and transcript expression of genes involved in fatty acid and eicosanoid metabolism in Atlantic salmon head kidney. Tissue fatty acid composition was reflective of the diet with respect to C18 PUFA and MUFA levels (% of total FA), and ω6:ω3 (0.5-1.5). Fish fed 0.3% EPA+DHA with high ω6 (0.3% EPA+DHA↑ω6) had the highest increase in proportions (1.7-2.3-fold) and in concentrations (1.4-1.8-fold) of arachidonic acid (ARA). EPA showed the greatest decrease in proportion and in concentration (by ~½) in the 0.3% EPA+DHA↑ω6 fed fish compared to the other treatments. However, no differences were observed in EPA proportions among salmon fed the high ω3 (0.3 and 1.0% EPA+DHA) and balanced (1.4% EPA+DHA) diets, and DHA proportions were similar among all treatments. Further, the transcript expression of elovl5a was lowest in the 0.3% EPA+DHA↑ω6 fed fish, and correlated positively with 20:3ω3, 20:4ω3 and EPA:ARA in the head kidney. This indicates that high dietary 18:3ω3 promoted the synthesis of ω3 LC-PUFA. Dietary EPA+DHA levels had a positive impact on elovl5a, fadsd5 and srebp1 expression, and these transcripts positively correlated with tissue ΣMUFA. This supported the hypothesis that LC-PUFA synthesis is positively influenced by tissue MUFA levels in Atlantic salmon. The expression of pparaa was higher in the 0.3% EPA+DHA↑ω6 compared to the 0.3% EPA+DHA↑ω3 fed fish. Finally, significant correlations between head kidney fatty acid composition and the expression of eicosanoid synthesis-related transcripts (i.e., 5loxa, 5loxb, cox1, cox2, ptges2, ptges3, and pgds) illustrated the constitutive relationships among fatty acids and eicosanoid metabolism in salmon.

Untargeted Screening of EPA/DHA Structured Phospholipids in Krill Oil by Chain-Lock-Driven Hydrophilic Interaction Liquid Chromatography Tandem Mass Spectrometry.

Eicosapentaenoic and docosahexaenoic acids structured phospholipids (PLEPA/DHA) have multiple biochemical and pharmacological effects on human health. In this study, EPA and DHA chains were locked under precursor ion scan (PreIS) mode for untargeted screening PLEPA/DHA in krill oil using hydrophilic interaction liquid chromatography tandem mass spectrometry (HILIC-MS/MS). The effect of collision energy and declustering potential on the fragmentation of EPA (m/z 301.2) and DHA (m/z 327.2) chains was studied. A total of 33 PLEPA/DHA were characterized (sn-1/sn-2) and quantified using regression models, including 16 PCEPA/DHA, 11 PEEPA/DHA, and 6 PIEPA/DHA. Afterward, this method was validated in terms of linearity (≥0.9978), sensitivity (LOD ≤ 4.02 µg·L-1), precision (RSDintraday ≤ 4.71%), and recovery (≥78.9%). Finally, the performance of HILIC-PreIS-MS/MS was compared with those of conventional methods, and the results indicated its superiority in selective screening PLEPA/DHA in krill oil.

Concentration of EPA and DHA from Refined Salmon Oil by Optimizing the Urea⁻Fatty Acid Adduction Reaction Conditions Using Response Surface Methodology.

This research focused on obtaining eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) (EPA+DHA) concentrates from refined commercial salmon oil (RCSO). Independent variables of the complexation process were optimized by means of the application of response surface methodology (RSM) in order to obtain the maximum content of such fatty acids (FAs). As a result of employing the optimized conditions for all the variables (6.0, urea:FA content ratio; -18.0 °C, crystallization temperature; 14.80 h, crystallization time; 500 rpm, stirring speed), high contents of EPA and DHA could be obtained from RCSO, achieving increases of 4.1 and 7.9 times in the concentrate, with values of 31.20 and 49.31 g/100 g total FA, respectively. Furthermore, a 5.8-time increase was observed for the EPA + DHA content, which increased from 13.78 to 80.51 g/100 g total FA. It is concluded that RCSO can be transformed into a profitable source of EPA and DHA (EPA+DHA), thus leading to a product with higher commercial value.

Fatty Acid Profiles of Triacylglycerols and Phospholipids of Sea-Cage Cultured Trachinotus blochii: A Comparative Study of Head, Viscera, Skin, Bone, and Muscle.

Trachinotus blochii (golden pompano) is an economically important cultured marine fish that is rich in polyunsaturated fat. The fatty acid profiles of triacylglycerols and phospholipids of T. blochii tissues were analyzed. Lipid contents in tissues followed the order of viscera (28.27%) > skin (17.25%) ≈ bone (16.18%) ≈ head (15.12%) > muscle (7.38%). In triacylglycerols (TAG), saturated fatty acids (palmitic acid predominated) were preferentially esterified in the sn-2 position, and monounsaturated fatty acids (oleic acid predominated) were mainly distributed in the sn-1, 3 positions. The numbers of n-3 polyunsaturated fatty acids (PUFA) in the sn-2 position were significantly greater than those in positions 1 and 3, while the n-6 PUFA were mainly found in the sn-1, 3 positions. Muscle TAG had a higher content of EPA+DHA (3.90%) than did the other tissues. In phosphatidylethanolamines, EPA+DHA in muscle (6.76%) predominated over that in other tissues. In phosphatidylcholines, EPA+DHA in bone (6.50%) predominated. This study is a guide for the biochemical and nutritional values of the T. blochii species and can be useful for further investigation of industrial applications. PRACTICAL APPLICATION: The high proportion of sn-2-palmitic acid (greater than 50%) is close to that of breast milk and the n-3 PUFA, especially EPA and DHA have the preferential distribution in the sn-2 position of triacylglycerol. Hence, golden pompano is an excellent dietary component for human nutrition and health.