Acids Of Neutral Lipids Research Articles

Auxin supplementation under nitrogen limitation enhanced oleic acid and MUFA content in Eustigmatos calaminaris biomass with potential for biodiesel production

Due to their lipid accumulation potential, microalgae are widely studied in terms of their use in the production of biodiesel. The present study was focused on determination of changes in the biomass production, biochemical composition, accumulation and distribution of fatty acids in neutral lipids, glycolipids, phospholipids and biodiesel properties of soil microalga Eustigmatos calaminaris in response to various levels of nitrogen stress and indole-3-acetic acid supplementation. The highest growth rate, the highest lipid content and daily lipid productivity were noted at the nitrogen limitation up to 25% with IAA supplementation. The increase in NL was associated with nutrient stress. An increase in the level of GL and PL were recorded upon the reduction of the nitrogen content (25% N) and the addition of IAA. The gas chromatography/mass spectrometry analysis demonstrated that C16:0, C16:1, and C18:1 were the main fatty acids in E. calaminaris lipids. As shown by the lipidomic analysis, the IAA supplementation in the nitrogen limitation variants enhanced the content of TAGs in C18:1 and monounsaturated fatty acids. The current findings indicated a potential strategy to improve the fatty acid profile in neutral lipids and high potential of E. calaminaris for biodiesel applications.

Profile of fatty acid lipid fractions of omega-3 fatty acid-enriched table eggs.

The omega-3 fatty acid (FA) enrichment of yolk is a key means one of the main objectives to improve the nutraceutical properties of eggs. We evaluated the effect of the dietary inclusion of extruded linseed fed to laying hens on the fatty acid composition of the polar and non-polar lipid classes of the eggs. Two groups of 36 Lohmann White Leghorn layers (65weeks old) were each fed one of two different diets for a period of 12weeks. The two diets consisted of a conventional cereal-based diet concentrate (C) and a diet concentrate containing 5% linseed (L). The inclusion of linseed in the diet increased the content of α-linolenic (C18:3n-3), eicosapentaenoic (C20:5n-3) and docosahexaenoic (C22:6n-3) acids in neutral lipids, while a concomitant decrease in arachidonic acid (C20:4n-6) was observed. As regards the polar fraction, the fatty acid composition was slightly affected by the dietary treatments except for C18:0 (+1.14 fold), C18:2n-6 (+1.23 fold), C18:3n-3 (+2.8 fold) and C22:6n-3 (+1.41 fold). Principal component analysis demonstrated that very long-chain FAs were more representative of polar lipids, except for C20:5n-3, while neutral lipids were characterized by dietary n-3 FA (C18:3n-3).

Salinity can change the lipid composition of adult Chinese mitten crab after long-term salinity adaptation.

The Chinese mitten crab (Eriocheir sinensis) is an euryhaline crustacean, whose adults migrate downstream to estuaries for reproduction. Lipids are believed to be involved in salinity adaptation during migration. This study investigated the effects of different salinities (0, 6, 12, and 18‰) on the total lipids, neutral lipids, and polar lipids contents, and fatty acid profiles in the gonads, hepatopancreas, and muscles of adult E. sinensis after 40 days of salinity adaptation. The results showed that the males and females from 12‰ treatment had the highest contents of total lipids and neutral lipids in their hepatopancreas and total lipids in the muscles. Notably, salinity had a greater effect on the fatty acid profiles in the hepatopancreas compared to that in the gonads and muscles. The male hepatopancreas treated with 18‰ salinity had the highest percentage of total n-6 polyunsaturated fatty acid (∑n-6PUFA) in both neutral lipids and polar lipids, while the percentage of total n-3 polyunsaturated fatty acid (∑n-3PUFA) in neutral lipids and polar lipids decreased significantly with increasing salinity in males. In females, the 0‰ treatment had the highest percentages of total saturated fatty acids in neutral lipids and polar lipids in the hepatopancreas, while the highest ∑n-3PUFA and ∑n-6PUFA in neutral lipids and polar lipids were detected in the 12‰ treatment group. In conclusion, brackish water could promote the accumulations of total lipids and neutral lipids in the hepatopancreas and change the fatty acid profiles of adult E. sinensis, particularly in the hepatopancreas after long-term salinity adaptation.

Differences in nutrient content of eggs and larvae as indicators for improvement of broodstock nutrition in walleye (Sander vitreus) production

The aim of this study was to increase our knowledge about the nutritional needs of walleye (Sander vitreus (Mitchill, 1818)) broodstock. Two dietary treatments were tested: the first consisted of frozen Atlantic mackerel (Scomber scombrus L., 1758) pieces with a supplement of experimental dry pellets and the second consisted of frozen Atlantic mackerel pieces with a supplement of commercial trout pellets. Hatching success was highest in eggs from the wild broodstock. Eggs and larvae from wild fish were characterized by the highest levels of linoleic (LOA; 18:2 n–6) and linolenic (LNA; 18:3 n–3) fatty acids in the neutral lipids. They had the lowest level of docosahexaenoic acid (DHA) in both neutral and polar lipids. The results suggest the importance of the amino acids leucine, lysine, methionine, and serine for better egg survival. Vitamin A1content was similar in eggs from wild fish and the younger broodstock from both treatment groups, but was 10 times lower in eggs from older broodstock. Vitamin A2was highest in eggs from wild fish. Our results showed that neither of the two diets really resulted in egg or larval quality that were comparable with that of wild fish.

Bioactive fatty acids in mantis shrimp, crab and caramote prawn: Their content and distribution among the main lipid classes

The profile and distribution of fatty acids in neutral lipids, phosphatidylethanolamine and phosphatidylcholine of appreciated crustaceans species caught in the Adriatic Sea during the autumn months, namely caramote prawn (Penaeus kerathurus), mantis shrimp (Squilla mantis) and crab (Liocarcinus vernalis), were investigated. The crab’s total fatty acid profile significantly differed from that of caramote prawn and mantis shrimp. Crab was the most valuable dietary source of omega-3 polyunsaturated fatty acids (n–3 PUFA), with approximately 2-fold higher eicosapentaenoic acid content (131.6±31.6mg/100g of edible part) than caramote prawn and mantis shrimp. The caramote prawn presented the highest furan fatty acids (F-acids) level (2.5±0.5mg/100g). All crustaceans preferentially accumulated the n–3 PUFA in phosphatidylethanolamine fraction. The F-acid distribution among the lipid classes changed according to the crustacean species. Crab presented F-acids mainly in the neutral lipid whereas caramote prawn contained them predominantly in the phospholipids. On the contrary, F-acids were not detected in the phosphatidylcholine of mantis shrimp. These differences in the distribution suggest different nutritional and health properties given by the consumption of the crustaceans investigated. Moreover, the F-acid profile of the different lipid classes could be used to discriminate these crustaceans.

Screening of marine microalgae isolated from the hypersaline Bardawil lagoon for biodiesel feedstock

Recently, microalgae have been attracting a wide attention as a source of high-lipid feedstock to produce biodiesel. A total of twenty one halophilic microalgae were isolated from the hypersaline Bardawil lagoon North Sinai, Egypt. Nine of them were further characterized with respect to biomass and fatty acid productivities. Biomass productivity as cellular dry weight (CDW), fatty acid content and, consequently, fatty acid productivity of the chlorophyte Tetraselmis elliptica was the highest among alltested strains (0.122 g CDW L−1 d−1, 77.36 mg g−1 CDW and 14.1 mg L−1 d−1, respectively). Lipid fractionation showed that total lipids represented 12.96 mg g−1 CDW and neutral lipids represented 37% of the total lipids with corresponding iodine value of 70.3 g I2/100 g oil. In all fractions, C16:0 and C18:1n-9 were predominant, being as high as 31 and 20% of total fatty acids in neutral lipids, 26 and 24% of total fatty acids in polar lipids and 28 and 26% of total fatty acids in phospholipids, respectively. This study demonstrates that the halophilic microalga T. elliptica isolated from hypersaline water is a promising species for biodiesel feedstock.

Lipids and Polysaccharides from Seeds of Stachys hissarica

The compositions of lipids and fatty acids and the carbohydrate complex from seeds of the endemic plant Stachys hissarica were established. Neutral lipids were dominated by fatty acids 18:2ω6 and 18:1. The principal acid in glyco- and phospholipids was 16:0. Fatty acids of neutral lipids contained trace quantities of 18:2 (5,6) laballenic acid with adjacent double bonds. The carbohydrate complex from S. hissarica seeds was studied and found to include water-soluble polysaccharides, pectinic substances, and hemicellulose. Their physicochemical properties were presented.

Analysis of Free Fatty Acids in Blood of Healthy Person and that of Hepatitis Patient

Polyunsaturated fatty acids (PUFA) are highly susceptible to oxidation and their levels can rapidly decrease under oxidative stress [1]. A concomitant increase in monounsaturated fatty acids such as oleic and palmtoleic acids is often observed probably as a result of the activation of Δ9-desaturase [1]. Analysis of fatty acid profiles is therefore of importance. Here we describe the analysis of plasma free fatty acids (FFA) only, because the measurement of fatty acids in neutral lipids, phospholipids, and total lipids has already been well documented. Plasma FFA can, furthermore, be produced by oxidatively damaged tissues because hydrolysis of phospholipids is stimulated by oxidative stress [2].

Biochemical and fatty acid dynamics during larval development in the razor clamEnsis arcuatus(Bivalvia: Pharidae)

This article reports on the changes in gross biochemical and fatty acid composition of the razor clam Ensis arcuatus larvae throughout development. Protein was the largest component of dried larval tissues. The energy required for embryogenesis in E. arcuatus oocytes was obtained from stored proteins and carbohydrates, while total lipids increased significantly. Lipids and carbohydrates have an important role as energy contributors from day 1 to day 8. During larval development the strategy was to indistinctly store energy reserves (protein, lipid and carbohydrate) to surpass metamorphosis. During embryonic development there was a gain in fatty acids of neutral and polar lipids. A depletion of fatty acids in neutral lipids was observed from day 1 to day 8 in E. arcuatus larvae, mainly due to the decrease in 16:0 and EPA. NMID fatty acids were present in amounts similar to those of some PUFAs in polar lipids, especially 22:2NMID.

Composition of neutral lipid classes and content of fatty acids throughout sourdough breadmaking

AbstractBroa is an example of bread that is a good candidate for inclusion in functional diets, so it deserves further in‐depth study of its chemical composition—namely with regard to evolution of the lipid profile throughout breadmaking, in order to assess whether mixing, fermentation, or baking affect its nutritional value (in terms of unsaturated fatty acids, UFA) based on the assumption that neutral lipids (NL) can be protein‐ or carbohydrate‐bound. Hence, constituent fatty acids in NL of maize (Zea mays) and rye flour (Secale cereale), and in sourdough and final broa manufactured from a mixture therefrom were quantitated. Methodologies of esterification of fatty acids, as well as of transesterification of acyl lipids and sterol esters (SE) were improved. The n‐hydrocarbons containing between 4 and 24 carbon atoms were then resolved and identified by gas–liquid chromatography. Regarding total neutral lipids (TNL) in all samples, 79–89% were TAGs, and 87–93% were TAGs and DAGs in the case of free lipids (FL). Furthermore, 73–85% of TNL in bound lipids (BL) and 65–80% of TNL in starch lipids (SL) were TAG and free fatty acids (FFA). Conversely, only 4–5%, 6–16%, and 7–10% of TNL in FL, BL, and SL, respectively, were SE and MAGs. TAGs and DAGs underwent partial hydrolysis during fermentation and baking; palmitic, oleic, and linoleic acids were dominant as products released. The nutritional value of broa lipids was apparent owing to their proportions of SE (4%) and DAG (9%), coupled with 52% of linoleic acid in all samples—as well as to the high contents of polyunsaturated versus monounsaturated or saturated fatty acids, and to the general dominance of UFA.

Dietary conjugated linoleic acid isomers change the unsaturation degree of hepatic fatty acids in neutral lipids but not in polar lipids

The fatty acid composition of phospholipids plays a key role in the structural and functional properties of cellular membrane. In this study, it was hypothesized that conjugated linoleic acid (CLA) isomer supplementation changes the unsaturation degree of the fatty acids of neutral lipids (NLs) but not those of polar lipids (PLs). Thus, the main goal was to determine the pattern of fatty acid incorporation into hepatic PL and NL fractions. Wistar male rats were fed cis(c)9,trans(t)11 and t10,c12 CLA isomers, separately or as a mixture. Whereas the t10,c12 isomer incorporation in the PL fraction was similar when supplemented either individually or as a mixture, the c9,t11 isomer reached the highest values of incorporation when combined with t10,c12. In the PL fraction, the linoleic acid did not change; but the arachidonic acid decreased, especially in the rats given the mixture. Also in this fraction, the t10,c12 isomer, either separately or as a mixture, decreased the amounts of n-6 long-chain (LC) polyunsaturated fatty acids (PUFA) and increased those of the n-3 LC PUFA relative to the control. In the NL fraction, linoleic acid incorporation followed the diet composition, whereas the arachidonic acid was similar among treatments. Facing CLA isomer supplementation, the present study suggests that fatty acid incorporation into phospholipids, through the balance between n-6 and n-3 LC PUFA, is dependent upon maintaining the unsaturation degree of cellular membrane.

Influence of irrigation-water salinity on lipids of Crambe abyssinica seeds

Lipids of Crambe abyssinica Hochst (Brassicaceae) seeds grown in hothouses in Israel and in the open in Uzbekistan in soil imported from the Aral Sea region were studied. It was found that the seed oil content decreased as the irrigation-water salinity increased. The content of total unsaturated fatty acids of neutral lipids was in the range 91.31–94.81%; of polar lipids, 69.59–83.78%.

Lipids from Rochelia cardiosephala fruit

In continuation of the study of lipids and lipophilic components of vegetative and generative plant organs, we studied previously uninvestigated lipids from Rochelia cardiosephala Bge. (Boraginaceae) fruit collected in Tashkent Oblast in 2008. This family in Uzbekistan numbers 117 species [1] and is interesting because of the presence in fruit oils of triacylglycerides including -3 and -6 fatty acids, which are active metabolism regulators. Total neutral lipids (NL) were isolated by extraction with hydrocarbons (bp 72–85°C) in a Soxhlet apparatus. Bound lipids were isolated from the defatted material by the Folch method [2]. Column chromatography over silica gel with elution by CHCl3 was used to separate a part of the NL that accompanied the fraction of bound lipids. The recovered amount was combined with the NL extracted by hydrocarbons so that the overall yield of NL was 14.35%; bound lipids, 1.11%. Phospholipids (PL) were eluted from the column by MeOH; glycolipids (GL), by acetone. Yield of GL, 0.79%; of PL, 0.42%. Analysis of NL by TLC (silica gel) using hexane:Et2O (4:1 and 1:1) showed that the principal components were triacylglycerides (TAG), hydrocarbons, free fatty acids (FFA), and aliphatic alcohols. GL were separated by TLC on silica gel [3]. The principal classes of them were sterylglycosides, sterylglycoside esters, and monoand digalactosyldiglycerides. Two-dimensional chromatography on silica gel [3] was used to establish the PL composition. Phosphatidylcholines, phosphatidylethanolamines, phosphatidylinosites, and phosphatidic acid were detected. Fatty acids of NL, GL, and PL were isolated and identified using literature methods [4, 5]. Table 1 presents the results. We can be seen that the qualitative composition of fatty acids from NL and PL included 14 components; from GL, 10. Palmitic dominated the saturated acids; octadecenoic and octadecadienoic, the unsaturated acids. Polyunsaturated fatty acids occurred in the NL (17.3%), GL (4.2%), and PL (3.2%). Neutral lipids consisted mostly (87.3%) of unsaturated fatty acids with 33.5% in the GL and 50.7% in the PL. Next unsaponified compounds (UC), the yield of which was 4.4%, were isolated from the total lipids. Total UC were separated from the fraction by preparative TLC on silica gel using hexane:Et2O (6:4). The yield was determined gravimetrically. Hydrocarbons (8.0 mass%), triterpenols + aliphatic alcohols (24.1), sterols (41.8), tocopherols (9.0), and unidentified components (17.1) were detected. The results indicated that the UC contained a significant quantity of biologically active compounds.

Linking Egg Thiamine and Fatty Acid Concentrations of Lake Michigan Lake Trout with Early Life Stage Mortality

The natural reproduction of lake trout Salvelinus namaycush in Lake Michigan is thought to be compromised by nutritional deficiency associated with inadequate levels of thiamine (vitamin B1) in their eggs. However, mortality driven by thiamine deficiency (commonly referred to as early mortality syndrome [EMS]) is not the only significant cause of low lake trout survival at early life stages. In this study, we sought to better understand the combined effects of variable levels of thiamine and fatty acids in lake trout eggs on prehatch, posthatch, and swim-up-stage mortality. We sampled the eggs of 29 lake trout females from southwestern Lake Michigan. The concentrations of free thiamine and its vitamers (e.g., thiamine monophosphate [TMP] and thiamine pyrophosphate [TPP]) as well as fatty acid profiles were determined in sampled eggs. Fertilized eggs and embryos were monitored through the advanced swim-up stage (1,000 degree-days). Three distinct periods of mortality were identified: prehatch (0-400 degree-days), immediately posthatch (401-600 degree-days), and swim-up (601-1,000 degree-days). Stepwise multiple regression analysis revealed (1) that cis-7-hexadecenoic acid in both neutral lipids (NL) and phospholipids (PL) correlated with prehatch mortality, (2) that docosapentaenoic acid in PL and docosahexaenoic acid in NL correlated with posthatch mortality, and (3) that total lipids, TPP, and palmitoleic acid in NL, linoleic acid, and palmitic acid in PL correlated with the frequency of EMS. These results indicate the complexity of early life stage mortality in lake trout and suggest that inadequate levels of key fatty acids in eggs, along with variable thiamine content, contribute to the low survival of lake trout progeny in Lake Michigan.

Influence of lipid class and fatty acid deficiency on survival, growth, and fatty acid composition in rainbow trout juveniles

Triplicate groups of rainbow trout (182 ± 51 mg) were fed four experimental casein–gelatin based diets containing different fatty acid levels for 8 weeks. Diet 1, containing only the oleic acid methyl ester (18:1 n − 9), was used as an essential fatty acids deficient diet. Diet 2, supplemented with olive and linseed oils was designed to provide moderate amount of linoleic (18:2 n − 6) and linolenic (18:3 n − 3) acids in the form of triglycerides. Diet 3 contained cod liver oil and provided highly unsaturated fatty acids (HUFA) as well as their precursors. Diet 4, supplemented with soy-refined lecithin, contained high levels of 18:2 n − 6 in the form of phospholipids. At the end of the experiment, the growth of fish fed the lecithin supplemented diet was significantly higher (17 fold increase) than that of the other groups (6–14 fold increase). Survival was significantly lower in fish fed the diet 1 in comparison to fish fed the other experimental diets (57.8% vs. 84.4–86.7%). Fish fed diets 1 and 4 contained significantly less total and neutral lipids in the whole body than fish fed diets 2 and 3. Whole body fatty acid profiles from both neutral and phospholipid fractions closely reflected dietary fatty acid composition. Fish fed linoleate containing phospholipids preferentially deposited this fatty acid in neutral lipids (33.0 ± 1.6%) in comparison to body phospholipids deposition (21.2 ± 1.0%). An increase of dietary linoleate also resulted in a significantly higher percentage of arachidonate (20:4 n − 6) in fish body phospholipids. In conclusion, selective accumulation of 18, 20, and 22 polyunsaturated fatty acids in body of juvenile rainbow trout is the function of fatty acid origin, e.g., lipid class, which has been very little studied in this species.

Lipolysis in dry-cured ham: Influence of salt content and processing conditions

Fatty acid composition of neutral lipids (NLs), polar lipids (PLs) and free fatty acids (FFA) from the intramuscular fat of Semimembranosus and Biceps femoris muscles was analysed in 46 Iberian dry-cured hams processed with different amounts of salt (6% high salt batch – HS vs. 3% low salt batch – LS w/w) and different processing systems (traditional – T vs. modified – M). Total amounts of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids in NLs decreased in similar proportions during processing of the hams as well as SFA, MUFA and PUFA in the PL fraction, whereas the amounts of SFA, MUFA and PUFA of FFAs significantly increased in Semimembranosus and Biceps femoris muscles. The amount of total fatty acids (TFA), from NLs and PLs, decreased in both muscles throughout the processing. Such a decline was more intense in HS hams than in LS ones, which could be a sign of a promoting effect of sodium chloride on lipolysis. However, the increase in FFA content throughout processing was not more intense in HS hams. Processing conditions studied in this work did not affect the changes in the fatty acid content of each fraction.

The effect of conjugated linoleic acid on the antioxidant enzyme defense system in rat hepatocytes.

Short-term effects of physiological concentrations of conjugated linoleic acid (CLA) on membrane integrity, metabolic function, cellular lipid composition, lipid peroxidation, and antioxidant enzymes were examined using rat hepatocyte suspension cultures. Incubation with CLA (5-20 ppm) for 3 h decreased the ability of hepatocyte plasma membranes to exclude trypan blue by approximately 25%, and caused leakage of cytosolic lactate dehydrogenase (LDH) into the medium. The significant decrease (P< 0.02) in hepatocyte viability as measured by LDH leakage during cell incubation with 10 and 20 ppm CLA was not associated with significant changes in cellular ATP content. Protein synthesis in hepatocytes was elevated (P < 0.05) in the presence of 5 and 10 ppm CLA, but at a higher concentration (20 ppm), protein synthesis was similar to that of control cells. Gluconeogenesis was maintained in cells incubated with lower concentrations of CLA (5 and 10 ppm) but was decreased (P < 0.02) at the higher concentration. Incubation with 20 ppm CLA for 3 h did not affect the specific activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting enzyme of cholesterol synthesis. Both cis-9,trans-11/trans-9,cis-11, and cis-10,trans-12/trans-10,cis-12 isomers of CLA were incorporated to a similar level into hepatocytes. Levels ranged from 3.9 to 4.1%, respectively, of total fatty acids in neutral lipids, and from 0.7 to 0.8%, respectively, of total fatty acids in phospholipids. Cellular lipid peroxidation remained unchanged in the presence of CLA (5-20 ppm), despite significant inhibition (P < 0.05) of superoxide dismutase. Catalase activity was maintained near control levels in the presence of 5 and 10 ppm CLA but was significantly decreased in the presence of 20 ppm CLA. Glutathione peroxidase activity was significantly decreased in the presence of 10 ppm CLA. The apparent sensitivity of the antioxidant enzyme defense system of liver cells to CLA, coupled with the lack of effect of CLA on lipid peroxidation in cells, suggests that cytotoxic effects of CLA as described by LDH leakage and decreased gluconeogenesis were not mediated by a prooxidant action in hepatocytes.

Lipid and fatty acid composition in non‐embryogenic calli and embryogenic tissues in wild cherry (Prunus avium)

In Prunus avium, the lipid and fatty acid composition of non‐embryogenic calli and embryogenic tissues was studied. The embryogenic tissues were characterised by a higher content of triglycerides and total phospholipids than non‐embryogenic calli. Neutral lipids (NL) from embryogenic tissues akppeared less saturated than NL from non‐embryogenic calli. Somatic embryogenesis was associated with considerable proportions of linoleic acid in both NL and phosphatidylcholine (PC) (23% in NL and 60% in PC), together with high proportions of palmitic acid in phosphatidylethanolamine (PE) and phosphatidylinositol (PI) (92% in PE and 62% in PI). Conversely, non‐embryogenic calli were characterised by a considerable proportion of palmitic acid in NL (74%) and high proportions of oleic acid in PE (100%) and PC (84%). These results suggest differences between the lipid biosynthetic pathway of embryogenic tissues when compared with that of non‐embryogenic calli.

Neutral lipids of chickpea flour and protein isolates

AbstractThe neutral lipids composition of defatted chickpea flour and two types of protein isolates has been studied. The main compounds in neutral lipids are triacylglycerols, free fatty acids, and diacylglycerols. Other compounds present are wax esters, free fatty alcohols, and free sterols. The main fatty acids in neutral lipids are C18:2 and C18:1 among the unsaturated, and C16:0 and C18:0 among the saturated acids. Free and esterified alcohols range from C16:0 to C28:0, the majority being those with an even number of carbon atoms. Sterols observed are β‐sito‐sterol, campesterol, stigmasterol, and δ‐5‐avenasterol. Triacyl‐glycerols are partially hydrolyzed, and the amounts of unsaturated sterols and unsaturated fatty acids are reduced as a result of the chemical treatment during production of the protein isolates.

Effects of a high n-3 fatty acid diet on membrane lipid composition of heart and skeletal muscle in normal swine and in swine with the genetic mutation for malignant hyperthermia

Knowledge concerning the genetic defects underlying malignant hyperthermia (MH) has expanded rapidly in recent years. In contrast, our understanding of the accompanying physiological changes is less clear. In this regard, the aim of this study was to determine whether normal swine and swine susceptible to MH (both heterozygous and homozygous animals) differ in their abilities to incorporate n-3 (omega 3) fatty acids into their skeletal and heart muscles. Swine of each genotype were fed either a diet rich in n-3 fatty acids (i.e., 5% fish oil) or an equal caloric diet low in n-3 fatty acids (i.e., 5% coconut oil). All dietary supplementations were given over a 13-week period. Subsequently, for each muscle type the following was determined: 1) the relative fatty acid profiles of eight different phospholipid classes and of neutral lipids, and 2) the total phospholipid and the total lipid content. The incorporation of n-3 fatty acids (i.e., eicosapentaenoic acid and docosahexaenoic acid) occurred within the various phospholipids and neutral lipids without influencing their total lipid content. The increased content of n-3 fatty acids in neutral lipids of skeletal muscle was related to a decreased content of medium-chain saturated fatty acids, whereas an increased incorporation of n-3 fatty acids into the membrane phospholipids was often related to a decreased content of linoleic acid and/or arachidonic acid. In general, the pattern of n-3 fatty acid incorporation was considerably different between the normal animals and the MH homozygous and heterozygous animals. The significant interaction between diet-induced n-3 fatty acid profiles and the stress-susceptible MH genotype may indicate an altered mechanism for fatty acid turnover and a repair mechanism to maintain cellular functions and structure.