Fat content and fatty acid compositions of 34 marine water fish species from the Mediterranean Sea

Fish is the best source of polyunsaturated fatty acids (PUFA), specifically n-3 fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid. The objective of the present study was to determine the fat content and fatty acid compositions of 34 marine water fish species from the Mediterranean Sea. The fatty acid compositions of fish consisted of 30.10-46.88% saturated fatty acids, 11.83-38.17% monounsaturated fatty acids and 20.49-49.31% PUFA. In most species, the following fatty acids were identified: mystiric acid (C14:0, 0.72-8.09%), pentadecanoic acid (15:0, 0.05-2.35%), palmitic acid (C16:0, 15.97-31.04%), palmitoleic acid (C16:1, 1.48-19.61%), heptadecanoic acid (C17:0, 0.31-1.84%), cis-10-heptadecenoic acid (C17:1, 0.17-2.01%), stearic acid (C18:0, 2.79-11.20%), oleic acid (C18:1n9, 2.44-28.97%), linoleic acid (C18:2n-6, 0.06-3.48%), arachidonic acid (C20:4n-6, 0.12-10.72%), cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n-3, 1.94-10%) and cis-4,7,10,13,16,19-docosahexaenoic acid (C22:6n-3, 3.31-31.03%). The proportions of n-3 PUFA ranged from 12.66% for annular seabream to 36.54% for European hake, whereas the proportions of PUFA n-6 were between 1.24% for oceanic puffer and 12.76% for flathead mullet. The results of this study show that these fish species were rich in n-3 PUFA, especially, eicosapentaenoic acid and docosahexaenoic acid.     

Comparison of fatty acid,mineral and proximate composition of body and legs of edible frog (Rana esculenta)

The fatty acid profile and mineral composition (calcium, magnesium, sodium, phosphorus, potassium, iron, zinc, manganese, silicon, boron, cadmium, chromium, nickel, aluminium, copper, and lead) by Inductively Coupled Plasma-Atomic Emission Spectometry (ICP-AES) and the proximate composition of the body and legs of edible frog (Rana esculenta) were investigated. The fatty acids occurring in the highest proportions in both the body and leg of frogs were mystiric acid (C14:0, 1.13–2.30%), palmitic acid (C16:0, 19.76–23.23%), stearic acid (C18:0, 3.61–6.29%), palmitoleic acid (C16:1, 7.06–13.08%), oleic acid (C18:1n-9 cis, 10.83–16.71%), linoleic acid (C18:2n-6, 6.44–6.71%), γ-linolenic (C18:3n-6, 0.13–0.27%), linolenic (C18:3n-3, 2.32–3.37%), cis-11,14,17-eicosatrienoic acid (C20:3n-3, 4.71–7.72%), cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n-3, 3.96–6.05%) and cis-4,7,10,13,16,19-docosahexaenoic acid (C22:6n-, 2.77–6.67%). Among the minerals determined, potassium was found to be highest, followed by phosphorus. Calcium, aluminium, cadmium, copper, lead, chromium, nickel, boron, silicon and zinc are found to be lower than the potential toxicity levels.     

Bioavailability of long-chain omega-3 polyunsaturated fatty acid enriched luncheon meats

(Nutr Diet 2005;62:130–137) Objective: To determine the acute and chronic effects of low doses of long chain (LC) n‐3 polyunsaturated fatty acids (PUFA) on plasma LC n‐3 PUFA levels. Design: In the acute study, six healthy omnivores, avoiding fish meals on the day prior to the study, provided a fasting blood sample initially and post prandially at four hours. In the chronic study, 12 healthy subjects provided a fasting blood sample at baseline and three weeks after daily consumption of the test food. Main outcome measures: Plasma non‐esterified fatty acid and phospholipid LC n‐3 PUFA composition. Statistical analysis: Differences in plasma non‐esterified fatty acids and phospholipid LC n‐3 PUFA. A pre‐ and post‐consumption of the test food were assessed using paired t‐tests (spss ). Results: The acute study demonstrated that a low dose of LC n‐3 PUFA (25% eicosapentaenoic acid and 75% docosahexaenoic acid) significantly increased eicosapentaenoic acid levels in plasma of human subjects postprandially from 0.30% to 0.42% of total non‐esterified fatty acids, a per cent change of 39% (P < 0.05). The chronic study demonstrated a significant increase in total n‐3 phospholipids from zero weeks (5.48% of total fatty acids) to three weeks (7.92% of total fatty acids), representing a per cent increase of 44% (P = 0.006). The n‐6 to n‐3 ratio of LC PUFA phospholipids demonstrated a significant reduction from 5.1 at zero weeks to 4.07 at three weeks, representing a reduction of 20% (P = 0.006). Conclusions: These findings demonstrate the bioavailability of LC n‐3 PUFA consumed as a low‐fat omega‐3‐enriched luncheon meat.     

Comparison of n-3 polyunsaturated fatty acid contents of wild and cultured Australian abalone

The fatty acid contents of wild and cultured Australian adult blacklip abalone, Haliotis rubra, were analysed by gas liquid chromatography. Wild abalone contained significantly higher levels of total n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (20:5n-3), docosapentaenoic acid (22:5n-3) and α-linolenic acid (18:3n-3) than cultured abalone (P<0.05). The predominant n-3 PUFA was docosapentaenoic acid in wild abalone, while in cultured abalone a high level of eicosapentaenoic acid was found. The concentration of docosahexaenoic acid (22:6n-3) was low in both wild and cultured abalone, and cultured abalone had a significantly higher percentage composition of this fatty acid than wild abalone (P<0.01). Significantly higher levels of arachidonic acid (20:4n-6), 22:2n-6, 22:4n-6 and total n-6 PUFA were also found in wild abalone than in cultured animals (P<0.05). The ratio of n-3 PUFA to n-6 PUFA was the same in wild and cultured abalone. Manipulation of nutrient sources of cultured abalone may influence their lipid composition. Consumption of either wild or cultured abalone will contribute to dietary n-3 PUFA intake, with benefits to human health.     

Nutritional Importance of Selected Fresh Fishes,Shrimps and Mollusks to Meet Compliance with Nutritional Guidelines of n-3 LC-PUFA Intake in Spain

Fishery products are the main source of dietary n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Following the European Commission’s request to address the risks and benefits of seafood consumption, and taking into account the great variability of nutrient and contaminant levels in fishery products, the present work aims to estimate the n-3 LC-PUFA provided per serving of selected fishes, shrimps and mollusks that are commonly consumed in Spain. This would enable the establishment of a risk–benefit analysis of fish consumption and provide recommendations for fish intake to comply with nutritional guidelines of n-3 LC-PUFA intake. We confirmed high variation in the pattern and contents of fatty acids for different species. n-6 PUFA were minor fatty acids, whereas palmitic (C16:0), oleic (C18:1 n-9), and mainly eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids were the major fatty acids in the sample. Therefore, consumption of 2–3 servings per week of a variety of fishery products may contribute to compliance with the recommended daily n-3 LC-PUFA intake while maintaining an adequate balance to avoid contaminant-derived potential risks (metals and others). Taking the fatty acid content of fishery products described in this study into consideration, it is advisable to include one serving of fatty fish per week in order to meet recommended n-3 LC-PUFA levels.     

Maternal fat intake during pregnancy and wheeze and eczema in Japanese infants: the Kyushu Okinawa Maternal and Child Health Study

PurposeThis cohort study examined the relationship between maternal intake of individual fatty acids, meat, and fish during pregnancy and the risk of wheeze and eczema in children aged 23–29 months because epidemiologic evidence on this topic is inconclusive.MethodsSubjects were 1354 Japanese mother-child pairs. Data on maternal intake during pregnancy were assessed with a validated diet history questionnaire. Data on symptoms of wheeze and eczema were based on criteria of the International Study of Asthma and Allergies in Childhood.ResultsSignificant inverse exposure-response relationships were observed between maternal intake of eicosapentaenoic acid (EPA) and EPA plus docosahexaenoic acid (DHA) during pregnancy and infantile wheeze although the adjusted odds ratios between extreme quartiles fell just short of the significance level. No such inverse relationships were detected for infantile eczema. Maternal intake of total fat, saturated fatty acids, monounsaturated fatty acids, total n-3 polyunsaturated fatty acids (PUFA), α-linolenic acid, DHA, total n-6 PUFA, linoleic acid, arachidonic acid, cholesterol, fish, and meat and the ratio of n-3 to n-6 PUFA consumption were not significantly related to infantile wheeze or eczema.ConclusionsHigher maternal intake of EPA and EPA plus DHA during pregnancy may reduce the risk of infantile wheeze.     

Effects of Different Dietary Fatty Acids on the Fatty Acid Compositions and the Expression of Lipid Metabolic-Related Genes in Mammary Tumor Tissues of Rats

In this study, the effects of dietary fatty acids on the fatty acid compositions and lipid metabolic-related genes expression in N-methyl-N-nitrosourea (MNU)-induced rat mammary carcinogenesis were evaluated. The 50-day-old female Sprague-Dawley rats were intervened by different dietary fats (15% wt/wt), including saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), n-6 polyunsaturated fatty acid (PUFA), n-3 PUFA, 1:1 n-6/n-3, 5:1 n-6/n-3, 10:1 n-6/n-3, and 1:2:1 S/M/P (1:1 n-6/n-3), alone or in combination with MNU. There was no mammary tumor occurrence in the control and MNU-treated n-3 PUFA groups after 18 wk. n-3 PUFA diet retarded the weight growth of rats. 1:1 n-6/n-3 diet significantly reduced the MNU-induced tumor incidence and tumor multiplicity compared with SFA, MUFA, n-6 PUFA, 5:1 n-6/n-3, 10:1 n-6/n-3 and 1:2:1 S/M/P diets (42.86% vs. 83.33%–92.31%, 0.79 vs. 2.62–2.85, P < 0.01). Additionally, 1:1 n-6/n-3 diet substantially increased cis-5,8,11,14,17-eicosapentaenoic acid and cis-4,7,10,13,16,19-docosahexaenoic acid levels, whereas it decreased C20:4 level and the mRNA expressions of fatty acid synthase, Cyclooxygenase-2 (COX-2), and 5-lipoxygenase (5-LOX) in mammary tissues (P < 0.05). These results suggest that 1:1 n-6/n-3 in the diet is effective in the prevention of mammary tumor development by increasing the n-3 PUFA content and reducing the expression of lipid metabolic-related genes.     

Evaluation of the composition of omega-3 fatty acids in dietary oil supplements

Aim: The aim of the present study was to determine the fatty acid composition of 19 dietary oil supplements that are commercially available in Australia, comparing findings with manufacturers' reported omega-3 fatty acid content. Methods: Fifteen fish oil supplements and four non-fish oil supplements were obtained from Australian retail stores. Fatty acids were derivatised, and fatty acid methyl esters were quantitated using classical GC-flame ionisation detection methods. Composition of eicosapentaenoic acid and docosahexaenoic acid reported by supplement manufacturers was compared with experimental values using the Bland-Altman plot. Results: The combined eicosapentaenoic acid and docosahexaenoic acid content in the fish oil and non-fish oil supplements was 17.63–71.45% and 0.00–0.05% respectively. A high level of congruency was observed for the composition of eicosapentaenoic acid and docosahexaenoic acid reported by manufacturers and determined experimentally (mean difference, eicosapentaenoic acid, 13.2 mg; docosahexaenoic acid, 12.8 mg). Conclusion: Current practice in pre-market assessment of complementary medicines in Australia is satisfactory for supplements examined in the present study. Intake of these fish oil supplements can be used to provide high levels of long-chain omega-3 fatty acids that would be otherwise difficult to achieve through normal dietary intake alone.     

Dietary n-3 and n-6 fatty acids alter avian metabolism: molecular-species composition of breast-muscle phospholipids

The effects of diets high in n-3 polyunsaturated fatty acids (PUFA; provided by fish oil), n-6 PUFA (sunflower oil) or in more-saturated fatty acids (tallow) on the distribution of subclasses of choline phospholipids (PC) and ethanolamine phospholipids (PE) from the breast muscle of broiler chickens were examined. Supplementation with the different fatty acids had no effect on the distribution of phospholipid subclasses. Feeding sunflower oil or tallow gave a molecular-species profile similar in both fatty acid subtype and proportion. In the diacyl PC phospholipids, 16 : 0-18 : 1n-9 and 16 : 0-18 : 2n-6 accounted for approximately 60 % of the total molecular species, whereas for the alkylenyl PC the predominant species were 16 : 0-18 : 1n-9 and 16 : 0-20 : 4n-6. Of the diacyl PE the dominant species was 18 : 0-20 : 4n-6 which accounted for 50 % of the molecular species, and of the alkylenyl PE the dominant species were 16 : 0-18 : 1n-9, 16 : 0-20 : 4n-6 and 18 : 0-20 : 4n-6. Supplementation with fish oil significantly increased levels of both eicosapentaenoic acid (20 : 5n-3) and docosahexaenoic acid (22 : 6n-3) in PC and PE when compared with either sunflower oil or tallow supplementation. The increase in the n-3 PUFA incorporation was associated with a corresponding decrease in the proportion of arachidonic acid (20 : 4n-6) in both PC and PE. Different dietary fats induce different patterns of fatty acid incorporation and substitution in the sn-2 position of the diacyl and alkylenyl PC and PE of avian breast muscle, and this finding is indicative of selective acyl remodelling in these two phospholipids.     

Replacement of fish oil with rapeseed oil in diets of Atlantic salmon (Salmo salar) affects tissue lipid compositions and hepatocyte fatty acid metabolism

Duplicate groups of Atlantic salmon post-smolts were fed five practical-type diets in which the added lipid was 100% fish oil [FO; 0% rapeseed oil (0% RO)], 90% FO + 10% RO (10% RO), 75% FO + 25% RO (25% RO), 50% FO + 50% RO (50% RO) or 100% RO, for a period of 17 wk. There were no effects of diet on growth rate or feed conversion nor were any histopathological lesions found in liver, heart, muscle or kidney. The greatest accumulation of muscle lipid was in fish fed 0% RO, which corresponded to significantly lower muscle protein in this group. The highest lipid levels in liver were found in fish fed 100% RO. Fatty acid compositions of muscle lipid correlated with RO inclusion in that the proportions of 18:1(n-9), 18:2(n-6) and 18:3(n-3) all increased with increasing dietary RO (r = 0.98-1.00, P < 0.013). The concentrations of eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)] in muscle lipid were significantly reduced (P < 0.05), along with total saturated fatty acids, with increasing dietary RO. Diet-induced changes in liver fatty acid compositions were broadly similar to those in muscle. Hepatic fatty acid desaturation and elongation activities, measured using [1-(14)C] 18:3(n-3), were increased with increasing dietary RO. Limited supplies of marine fish oils require that substitutes be found if growth in aquaculture is to be maintained such that fish health and product quality are not compromised. Thus, RO can be used successfully as a substitute for fish oil in the culture of Atlantic salmon in sea water although at levels of RO >50% of dietary lipid, substantial reductions occur in muscle 20:5(n-3), 22:6(n-3) and the (n-3)/(n-6) polyunsaturated fatty acid (PUFA) ratio, which will result in reduced availability of the (n-3) highly unsaturated fatty acids that are beneficial for human health.     

Erythrocyte α-linolenic acid is associated with the risk for mild dementia in Korean elderly

n-3 polyunsaturated fatty acids (PUFA) play an important role in brain development and function, but there is conflicting evidence between the relationship of n-3 PUFA and dementia in the elderly. The purpose of the present study was to test the hypothesis that n-3 PUFA content of erythrocytes is associated with mild dementia in elderly Koreans. Fifty-seven elderly (age ≥65 years) patients (19 male, 38 female) were recruited, and indicators of dementia (intake, erythrocyte fatty acid composition, and Mini-Mental Status Examination—Korean Version [MMSE-K]) were evaluated. Patients were divided into groups based on their MMSE-K score: normal control group (score >21 [n = 24]) and deficit group (score ≤21 [n = 33]). Multivariate-adjusted regression analysis showed that a higher level of α-linolenic acid (ALA; 18:3n-3) significantly decreased the risk of mild dementia after adjusting for age, sex, and height. MMSE-K score was also significantly and positively associated with erythrocyte ALA and total n-3 PUFA. However, erythrocyte levels of docosahexaenoic acid (22:6n-3) and eicosapentaenoic acid (20:5n-3) were not significantly related with the risk of mild dementia and MMSE-K score. Dietary intake was also not significantly associated with the risk of mild dementia and MMSE-K score after adjusting for age, sex, height, and energy intake. In conclusion, ALA derived from plant sources of n-3 PUFA, but not eicosapentaenoic acid and docosahexaenoic acid from fish, decreased the risk for mild dementia among the Korean elderly.     

Detection of omega-3 fatty acid in designer eggs using hyperspectral imaging

Quantification of n-3 polyunsaturated fatty acids (PUFA) is an important aspect in quality control of designer eggs. Prediction of these fatty acids would be of value for egg grading stations. The aim of the present study was to evaluate the ability of hyperspectral imaging (HSI) to classify the eggs according their content in n-3 PUFA as a rapid and non-destructive technique. Furthermore, HSI was used to predict the content of n-3 PUFA in designer eggs. Normal eggs, eggs containing 75 mg and eggs containing 125 mg docosahexaenoic acid were purchased from a grocery store. After hyperspectral transmittance images were collected in the spectral region of 900–1,700 nm, the eggs were broken and analyzed chemically in order to measure fatty acid content. Regions of interest (ROIs) of about 3,000 pixels from each egg were selected. K-means analysis was performed to classify eggs into the three aforementioned types. The classification accuracy was 100%. A partial least-squares regression model was built and used to link the ROIs with results obtained from the chemical analysis. The correlation coefficients between the measured and predicted values of alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid were 0.94, 0.73 and 0.87, respectively. The root mean square error values for the validation sets were 38.65, 3.31 and 7.03, respectively. These results showed that HSI could be used both for discriminating the eggs between normal and designer eggs and for prediction of n-3 PUFA content in eggs.     

Fatty acid and amino acid composition of raw and hot smoked sturgeon (Huso huso,L. 1758)

Changes in fatty acid and amino acid composition in hot smoked sturgeon (Huso huso, L. 1758) were studied. The sturgeon was smoked for 20 min at 30°C, followed by 90 min at 50°C and 40 min at 80°C. The palmitic acid (C16:0) and stearic acid (C18:0) increased (P<0.05) from 17.70% to 27.52% and from 7.49% to 13.63% after smoking, respectively. The oleic acid content in smoked sturgeon decreased from 28.29% to 25.93%, but no change (P>0.05) was observed in the total monounsaturated fatty acid composition of fish after smoking. Total polyunsaturated fatty acid, eicosapentaenoic acid and docosahexaenoic acid contents decreased from 21.03% to 4.93%, from 4.65% to 0.49% and from 12.41% to 0.51% in sturgeon after smoking, respectively. The total n-3 and n-6 contents and the n-3/n-6 ratio of raw and smoked sturgeon were 17.48–1.35, 3.54–3.58 and 4.94–0.38, respectively. The atherogenic index and index of thrombogenicity values of raw and smoked sturgeon were determined as 1.01–0.31 and 1.93–1.24, respectively. The smoking process caused an increase (P<0.05) in aspartic acid>isoleucine>methionine>hidoksil-l-proline>valine, and a decrease (P<0.05) in glutamic acid>serine>threonine>leucine>tyrosine>histidine>lysine>proline. However, the changes in alanine, glycine and phenylalanine were insignificant (P>0.05).     

The quality properties and saturated and unsaturated fatty acid profiles of quail egg: the alterations of fatty acids with process effects

The nutritional composition (moisture, ash, crude protein, available carbohydrates, total lipids), energy value, some quality characteristics (yolk weight, albumen weight and shell weight), cholesterol level and fatty acid profiles of quail egg were determined (p<0.01). The protein content of quail egg was higher than laying hen's egg. The fatty acid composition of quail egg yolk consisted of 24 fatty acids including saturated fatty acids (C14:0, C16:0, C17:0, C18:0, C20:0, C22:0, C24:0), monounsaturated fatty acids (C15:1, C16:1, C17:1, C18:1n9, C18:1n7, C22:1n9, C24:1) and polyunsaturated fatty acids (C18:2n6t, C18:2n6c, C18:3n6, C18:3n3, C20:2, C20:3n6, C20:3n3, C20:4n6, C22:2, C20:5n3, C22:6n3). The total cholesterol level of quail egg was found to be 73.45±1.07 mg/100 g. Linoleic acid (C18:2n6c) (10.28%), arachidonic acid (C20:4n6) (1.92%) and cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n3) (0.63%) were the major polyunsaturated fatty acids in the fatty acid content of quail egg yolk, whereas oleic acid (C18:1n9c) was the major monounsaturated fatty acid comprising 26.71% in the yolk. The palmitic acid (C16:0) and stearic acid (C18:0) levels were 16.62% and 6.89%, respectively. Total omega-3 was detected as 1.16% in raw egg whereas it was 0.82% in soft-boiled (rafadan) egg. The polyunsaturated fatty acid/saturated fatty acid proportion was 0.58 and 0.64 for raw and processed yolk, respectively.     

Reduction in n-3 PUFA levels and EPA/AA ratio in serum after desert travels in China

OBJECTIVES: The effects of 3 months of desert travel in China on serum fatty acids and tocopherol were studied. METHODS: In project staff members (6 males, 3 females, aged 19-27 years), serum levels of fatty acids and alpha-tocopherol were analyzed before and after travel by gas liquid chromatography and high-performance liquid chromatography, respectively. RESULTS: Comparison of the levels before and after the trip showed no differences in serum total cholesterol, triglycerides, total protein or alpha-tocopherol. There were no changes in the levels of total fatty acids, while the percentage of polyunsaturated fatty acids increased (p < 0.05). Levels of n-3 PUFA lowered from 166 micrograms/ml to 103 micrograms/ml, and those of n-6 PUFA had increased from 988 micrograms/ml to 1140 micrograms/ml after the trip (p < 0.01 and p < 0.001, respectively). No change was observed in the serum levels of alpha-linolenic acid (C18:3n-3), but lowering of the levels of eicosapentaenoic acid (EPA, C20:5n-3) from 41.4 micrograms/ml to 16.3 micrograms/ml and docosahexaenoic acid (DHA, C22:6n-3) from 107.8 micrograms/ml to 71.7 micrograms/ml was found after the trip (p < 0.05 and p < 0.01, respectively). Serum levels of linoleic acid (LA, C18:2n-6) increased from 832 micrograms/ml to 598 micrograms/ml (p < 0.001), and arachidonic acid (AA, C20:4n-6) tended to increase. The ratios of n-3/n-6 PUFA and EPA/AA decreased from 0.171 to 0.091 and from 0.258 to 0.096 after the trip, respectively (p < 0.01 for both). CONCLUSIONS: Our findings indicated that 3 months of desert travel increased the serum levels of n-6 PUFA and LA and reduced the serum levels of n-3 PUFA and EPA and the ratios of n-3/n-6 PUFA and EPA/AA, possibly due to a relative essential fatty acid deficiency.     

Long-chain n-3 polyunsaturated fatty acid dietary recommendations are moderately efficient in optimizing their status in healthy middle-aged subjects with low fish consumption: a cross-over study

Several dietary recommendations have been made for marine n-3 polyunsaturated fatty acid (PUFA) intake; however, the effectiveness of these fatty acids has not been thoroughly examined. The aim of this study was to investigate whether public-aimed dietary recommendations for long-chain n-3 PUFA from oily fish or fish oil supplements are efficient in optimizing their status in red blood cells (RBCs) and platelets of healthy middle-aged subjects with low customary fish consumption. In a randomized, cross-over trial conducted over an 8-week period and separated by a 6-month washout period, 33 participants received an oily fish (salmon), providing 274 mg eicosapentaenoic acid (EPA) + 671 mg docosahexaenoic acid (DHA) per day, or a commercial fish oil supplement, providing 396 mg EPA + 250 mg DHA per day. Blood samples were collected before and after each intervention period, and RBCs and platelets were used for analysis of fatty acids. After 8 weeks, there were significant increases in EPA and DHA content in RBCs and platelets with both salmon and fish oil capsules. The increase in EPA in both RBCs and platelets was higher with capsules, whereas the increase in DHA in both RBCs and platelets was higher with salmon. In spite of the quantitative and qualitative differences between n-3 fatty acid profiles in salmon and the fish oil supplement, the overall incorporation of these fatty acids into RBCs and platelets did not differ in our short-term study (P > .05). The sum of EPA + DHA significantly increased in both compartments following dietary recommendations for oily fish and fish oil supplements intake in middle-aged healthy subjects with low baseline long-chain n-3 PUFA status, although targeted values with optimal cardioprotective effect of more than 8% were not achieved.     

Omega-3 polyunsaturated fatty acid profiling using fingertip-prick whole blood does not require overnight fasting before blood collection

Fatty acid profiling through the rapid analysis of capillary blood collected by fingertip prick could enable economical screening for omega-3 polyunsaturated fatty acid (PUFA) status, although the typical requirement of fasting prior to sample collection may limit application. We hypothesize that moderate changes in omega-3 biomarkers determined from fingertip-prick blood will occur and correspond to omega-3 PUFA content of the meals. Eight participants consumed a single breakfast with high fat, high fat with omega-3 functional foods, and low fat and low fat with fish oil capsules in a cross-over design. The fatty acid composition of fingertip-prick blood total lipid and venous blood erythrocyte total lipid, plasma total lipid, plasma triacylglycerol, and plasma phospholipids were analyzed at baseline and 1, 2, 3 and 4 hours after each single breakfast consumption. Omega-3 blood biomarkers; % of omega-3 highly unsaturated fatty acid (HUFA) in total HUFA, weight % of eicosapentaenoic acid+docosahexaenoic acid, weight % of eicosapentaenoic acid+omega-3 docosapentaenoic acid+docosahexaenoic acid, and the ratio of total omega-6 PUFA to total omega-3 PUFA in fingertip-prick blood, did not change from baseline during the postprandial period (P > .05). However, meal type yielded lower (P < .05) % omega-3 HUFA in total HUFA in the low fat meal (22.8 ± 3.9) as compared with the low fat with omega-3 (24.2 ± 3.9) and, the high fat (23.8 ± 4) meals. The ratio of total omega-6 PUFA to total omega-3 PUFA was generally higher in meals without omega-3 compared with omega-3. In conclusion, determinations of omega-3 status by fingertip-prick blood sampling may not require prior overnight fasting.     

Assessing the environment for regulatory change for eicosapentaenoic acid and docosahexaenoic acid nutrition labeling

This review examines issues related to the development of a recommended daily allowance or adequate intake, two of the categories of dietary reference intakes, for the long-chain omega-3 polyunsaturated fatty acids (omega-3 PUFAs), eicosapentaenoic acid (EPA, 20:5 n-3), and docosahexaenoic acid (DHA, 22:6 n-3). Although some have suggested a dietary intake of two servings of fatty fish per week or supplement intake of 500 mg/day EPA plus DHA, based on evidence from epidemiologic and clinical studies of cardiovascular benefit from regular fish or fish-oil consumption, supplementation with EPA and/or DHA may also have antidepressant and mood-stabilizing effects. Omega-3 PUFA biology is complex and chronic disease outcomes are sometimes difficult to prove, yet the possibility of benefit for a substantial portion of the population from increased omega-3 PUFA intake is a public health issue that must be addressed responsibly and be based on significant scientific evidence.     

Fatty acid, cholesterol and fat-soluble vitamin composition of wild and captive freshwater crayfish (Astacus leptodactylus)

The proximate analysis (dry matter, protein, fat and ash), cholesterol, fatty acid and fat-soluble vitamin compositions of the tail muscle of wild caught and captive crayfish (Astacus leptodactylus) were investigated. Captive crayfish contained higher moisture and fat content than wild crayfish. In contrast, wild crayfish contained a higher level of crude protein, ash and n-3 polyunsaturated fatty acids (PUFA), particularly eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) than captive crayfish. Arachidonic acid (C20:4 n-6) was the major n-6 PUFA in wild A. leptodactylus, and linoleic acid (C18:2 n-6) was the major n-6 PUFA in captive A. leptodactylus. The percentages of total saturated fatty acids (SFA), PUFA, and n-3/n-6 ratio were higher in wild crayfish and total monounsaturated fatty acids (MUFA) were lower. Although differences existed between wild and captive crayfish in vitamins A (p??0.05). The differences may be originated from the diet provided to captive crayfish. Since wild A. leptodactylus contained higher n-3/n-6 ratio than captive A. leptodactylus, crayfish farms can potentially produce a better quality of crayfish meat by increasing the PUFA n-3 (especially DHA and EPA) in the diets of A. leptodactylus.     

Comparison of n-3 polyunsaturated fatty acid contents of wild and cultured Australian abalone

The fatty acid contents of wild and cultured Australian adult blacklip abalone, Haliotis rubra, were analysed by gas liquid chromatography. Wild abalone contained significantly higher levels of total n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (20:5n-3), docosapentaenoic acid (22:5n-3) and alpha-linolenic acid (18:3n-3) than cultured abalone (P<0.05). The predominant n-3 PUFA was docosapentaenoic acid in wild abalone, while in cultured abalone a high level of eicosapentaenoic acid was found. The concentration of docosahexaenoic acid (22:6n-3) was low in both wild and cultured abalone, and cultured abalone had a significantly higher percentage composition of this fatty acid than wild abalone (P<0.01). Significantly higher levels of arachidonic acid (20:4n-6), 22:2n-6, 22:4n-6 and total n-6 PUFA were also found in wild abalone than in cultured animals (P<0.05). The ratio of n-3 PUFA to n-6 PUFA was the same in wild and cultured abalone. Manipulation of nutrient sources of cultured abalone may influence their lipid composition. Consumption of either wild or cultured abalone will contribute to dietary n-3 PUFA intake, with benefits to human health.