Composition and seasonal variation of fatty acids of <Emphasis Type="Italic">Diplodus vulgaris</Emphasis> L. from the Adriatic Sea

Muscle tissue from the common two-banded sea bream Diplodus vulgaris L. originating from the Adriatic Sea, Croatia, was analyzed. The FA composition of neutral (TAG) and polar (PE, PC, PI/PS) lipid classes was determined, as well as the lipid and water contents during winter and summer periods. Both the total lipid and water contents were higher in the winter period. We identified 16 different FA. The major constituents of the total FA in both seasons were saturates: palmitic (16∶0) and stearic acids (18∶0); monoenes: oleic (18∶1n−9) and palmitoleic acids (16∶1n−7); and polyunsaturates: arachidonic acid (20∶4n−6), EPA (20∶5n−3), and DHA (22∶6n−3), but their amounts and ratios differed significantly between the two seasons and between lipid fractions. The FA composition showed a noticeable pattern of seasonality that reflected fluctuations mainly in TAG. The diminution of the monounsaturated FA content in the summer was clearly followed by an increase in PUFA content. Diplodus vulgaris is a good source of natural n−3 PUFA and would therefore be suitable for inclusion in highly unsaturated low-fat diets.     

Fatty acid profiles and relative mobilization during fasting in adipose tissue depots of the American marten (Martes americana)

The American marten (Martes americana) is a boreal forest marten with low body adiposity but high metabolic rate. The study describes the FA composition in white adipose tissue depots of the species and the influence of food deprivation on them. American marten (n=8) were fasted for 2 d with 7 control animals. Fasting resulted in a 13.4% weight loss, while the relative fat mass was >25% lower in the fasted animals. The FA composition of the fat depots of the trunk was quite similar to other previously studied mustelids with 14∶0, 16∶0, 18∶0, 16∶1n−7, 18∶1n−9, and 18∶2n−6 as the most abundant FA. In the extremities, there were higher proportions of monounsaturated FA (MUFA) and PUFA. Food deprivation decreased the proportions of 16∶0 and 16∶1n−7, while the proportion of long-chain MUFA increased in the trunk. The mobilization of FA was selective, as 16∶1n−7, 18∶1n−9, and particular n−3 PUFA were preferentially mobilized. Relative mobilization correlated negatively with the carbon chain length in saturated FA (SFA) and n−9 MUFA. The Δ9 desaturation of SFA enhanced the mobilization of the corresponding MUFA, but the positional isomerism of the first double bond did not correlate consistently with relative mobilization in MUFA or PUFA. In the marten, the FA composition of the extremities was highly resistant to fasting, and the tail tip and the paws contained more long-chain PUFA to prevent the solidification of lipids and to maintain cell membrane fluidity during cooling.     

Gas chromatography-chemical ionization-mass spectrometric fatty acid analysis of a commercial supercritical carbon dioxide lipid extract from New Zealand green-lipped mussel (Perna canaliculus)

Supercritical fluid extracts of New Zealand green-lipped mussels (NZGLM) have been suggested to have therapeutic properties related to their oil components. The large number of minor FA in NZGLM extract was characterized by a GC-CIMS/MS method that excels at identification of double-bond positions in FAME. The extract contained five major lipid classes: sterol esters, TAG, FFA, sterols, and polar lipids. The total FA content of the lipid extract was 0.664 g/mL. Fifty-three unsaturated FA (UFA) were fully identified, of which 37 were PUFA, and a further 21 UFA were detected for which concentrations were too low for assignment of double-bond positions. There were 17 saturated FA, with 14∶0, 16∶0, and 18∶0 present in the greatest concentration. The 10 n−3 PUFA detected included 20∶5n−3 and 22∶6n−3, the two main n−3 FA; n−3 PUFA at low concentrations were 18∶3, 18∶4, 20∶3, 20∶4, 21∶5, 22∶5, 24∶6, and 28∶8. There were 43 UFA from the n−4, n−5, n−6, n−7, n−8, n−9, n−10, n−11 families, with 16∶2n−4, 16∶1n−5, 18∶1n−5, 18∶2n−6, 20∶4n−6, 16∶1n−7, 20∶1n−7, 16∶1n−9, 18∶1n−9, and 20∶1n−9 being the most abundant. In general, we estimated that FAME concentrations greater than 0.05% (w/w) were sufficient to assign double-bond positions. In total, 91 FA were detected in an extract of the NZGLM, whereas previous studies of fresh flesh from the NZGLM had reported identification of 42 FA. These data demonstrate a remarkable diversity of NZGLM FA.     

Hyperphagia modifies FA profiles of plasma phospholipids,plasma FFA,and adipose tissue TAG

Hyperphagia was achieved by continuous intracerebroventricular infusion of a melanocortin receptor antagonist (HS024; Neosystem, Strasbourg, France) in rats. The effects of hyperphagia on FA composition and concentration of plasma phospholipids (PL), plasma FFA, and adipose tissue TAG were studied in rats for 8 d [short-term hyperphagia (STH); n=8], or 28 d [longterm hyperphagia (LTH); n=9]. The control rats were treated with artificial cerebrospinal fluid for 8 d (n=8) or 28 d (n=10). The rats were fed the same regular diet. In STH rats the plasma PL and fasting plasma FFA contained higher concentrations of saturated FA (SFA) and monounsaturated FA (MUFA), and plasma FFA contained lower n−6 PUFA than in the control rats. In LTH rats the plasma PL contained higher concentrations of SFA, MUFA, and n−3 PUFA and higher proportions of 16∶1n−7 and 18∶1n−9 at the expense of 18∶2n−6 than in the control rats. In LTH rats the abundant dietary intake of 18∶2n−6 did not enrich 18∶2n−6 of the plasma PL or adipose tissue TAG. In LTH rats the fasting plasma FFA contained more than twofold higher concentrations of SFA and MUFA, and higher proportions of 16∶1n−7 and 18∶1n−9 at the expense of 18∶2n−6 than in the control rats. This animal obesity model shows that LTH affects the FA composition and concentration of plasma PL, plasma FFA, and adipose tissue TAG, a result consistent with changes associated with increased risk of various diseases in humans. These results also demonstrate that LTH alters the FA composition of plasma PL and adipose tissue TAG in a way that does not reflect the FA composition of dietary fat.     

Lipid and FA composition of the pearl oyster <Emphasis Type="Italic">Pinctada fucata martensii</Emphasis>: Influence of season and maturation

The lipid and FA composition of the total lipids of the pearl oyster Pinctada fucata martensii, in different seasons and in different areas, were analyzed to clarify its lipid physiology and to estimate the possible influence of its prey phytoplankton. TAG and sterols were the major components in the neutral lipids in all conditions, whereas high levels of phospholipids (PE and PC) were found in the polar lipids. The major FA in the TAG in all samples were 14∶0, 16∶0, and 18∶0 as saturated FA (saturates); 16∶1n−7, 18∶1n−9, and 18∶1n−7 as monoenoic FA (monoenes); and 20∶4n−6 (arachidonic acid: AA), 20∶5n−3 (EPA), and 22∶6n−3 (DHA) as PUFA. The major components found in the polar lipids were 16∶0 and 18∶0 as saturates; 22∶2n−9, 15 and 22∶2n−7, 15 as non-methylene-interrupted dienes (NMID), and AA, 22∶3n−6, 9, 15, EPA, and DHA as PUFA. Although it is a marine animal, characteristically high levels of AA were found in both the TAG and phospholipids. This result suggests that lipids of P. fucata may be influenced by those of its phytoplanktonic prey. The increase in levels of NMID from TAG to PE with a decrease in those of monoenes suggests that the tissues of this species are able to biosynthesize only the less unsaturated PUFA, such as NMID. In particular, NMID derivatives are considered to be biosynthesized in the PE; thus, they might play a particular role in the membrane, because NMID were characteristically localized only in the PE.     

Lipid class and fatty acid composition of the boreal soft coral Gersemia rubiformis

Total lipid, phospholipid, and FA composition and distribution of FA between polar lipids (PL) and neutral lipids (NL) were investigated in the boreal soft coral Gersemia rubiformis from the Bering Sea. The total lipids were mostly hydrocarbons and waxes (33.7%) and PL (33.1%). The content of monoalkyldiacylglycerols (9.7%) exceeded the content of TAG (6.7%). PC and PE constituted 31.4% and 25.6% of total phospholipids, respectively. Principal FA were 16∶0, 16∶1n−7, 18∶0, 18∶1n−9, 18∶1n−7, 20∶1n−7, 20∶4n−6, 20∶4n−3, 20∶5n−3 22∶5n−3, 22∶6n−3, 24∶5n−6, and 24∶6n−3. Most n−6 PUFA (52% of total FA) were associated with the PL fraction; this was especially true for arachidonic and tetracosapentaenoic acids. The NL were enriched with mono-, di-, trienoic, and n−3 PUFA. The variation in EPA levels in both NL and PL suggests an origin of this acid from lipids of diatoms consumed by the corals.     

<Emphasis Type="Italic">sn</Emphasis>-Position determination of phospholipid-linked fatty acids derived from erythrocytes by liquid chromatography electrospray ionization ion-trap mass spectrometry

The sn-position of FA in membrane lipids has an influence on the physiological function of cells, is predictive for diseases, and therefore is useful for diagnostics. The current study compares the compositions of acyl chain substituents in the sn-1 and sn-2 positions of the glycerol backbones of phospholipids derived from human erythrocytes by using RP-HPLC coupled with on-line electrospray ionization ion trap MS. Preferential loss of the acyl group in the sn-1 position was used to determine the degree of regiospecific preference exhibited by the phospholipid molecules. The identities of the molecular species and the positions of the acyl substituents were identified using product-ion spectra of major precursor ions selected from the mass spectra averaged across peaks in the total ion chromatogram. Saturated FA were found to be located mainly in the sn-1 position of the glycerol backbones of erythrocyte phospholipids, whereas PUFA were found primarily in the sn-2 position. All measured phospholipids revealed palmitic acid (16∶0) at the sn-1 position. Linoleic acid (18∶2n−6) and arachidonic acid (20∶4n−6) were found to be attached exclusively to the sn-2 position of the backbone, whereas eicosadienoic (20∶2n−6) and eicosatrienoic acid (20∶3n−9) occurred in both positions of the backbone of PC. Oleic (18∶1n−9), linoleic (18∶2n−6), and octadecatrienoic (18∶3) acids of PE and PS were linked to both positions. Lignoceric acid (24∶1n−9) was found to be strictly localized at the sn-2 position, whereas nervonic (24∶1n−9) acid of PS was associated with both positions of the backbone. A detailed analysis of the blood cell membrane lipids by MS might be helpful to characterize postprandial kinetics of pharmacological or dietary lipid applications, as well as environmental influences on cell membranes.     

Comparison of the effects of dietary alpha-linolenic,stearidonic, and eicosapentaenoic acids on production of inflammatory mediators in mice

The effects of dietary stearidonic acid (18∶4n−3) on inflammatory mediator release in whole blood and splenocytes was investigated in Balb/c mice, and the effects were compared with those of two other n−3 PUFA: α-linolenic acid (18∶3n−3) and EPA (20∶5n−3). TAG mixtures containing 10% of 18∶4n−3, 18∶3n−3, or 20∶5n−3 as the respective sole n−3 PUFA were enzymatically synthesized. Diets containing synthesized TAG mixtures were fed to Balb/c mice for 3 wk. The release of prostaglandin E₂ (PGE₂) and tumor necrosis factor (TNF) were measured in whole blood and splenocytes stimulated with lipopolysaccharide. In whole blood, the production of INF was suppressed by all dietary n−3 PUFA (18∶3n−3, 18∶4n−3, and 20∶5n−3) as compared with the control diet, which contained TAG prepared from safflower oil. PGE₂ production was not significantly changed. Differences among the n−3 PUFA (18∶3n−3), 18∶4n−3, and 20∶5n−3) were not observed. In splenocytes, PGE₂ production was suppressed by dietary n−3 PUFA, but TNF production was not. GC analysis of plasma and splenocyte FA profiles showed an increase in the levels of 20∶4n−3, 20∶5n−3, and 22∶6n−3 in mice fed the diet containing 18∶4n−3.     

Dietary fish oil dose-response effects on ileal phospholipid fatty acids and contractility

We have reported that dietary fish oil (FO) leads to the incorporation of long-chain n−3 PUFA into the gut tissue of small animal models, affecting contractility, particularly of rat ileum. This study examined the FO dose response for the incorporation of n−3 PUFA into ileal tissue and how this correlated with in vitro contractility. Groups of ten to twelve 13-wk-old Wistar-Kyoto rats were fed 0, 1, 2.5, and 5% FO-supplemented diets balanced with sunflower seed oil for 4 wk, after which ileal total phospholipid FA were determined and in vitro contractility assessed. For the total phospholipid fraction, increasing the dietary FO levels led to a significant increase first evident at 1% FO, with a stepwise, nonsaturating six-fold increase in n−3 PUFA as EPA (20∶5n−3), DPA (docosapentaenoic acid, 22∶5n−3), and DHA, but mainly as DHA (22∶6n−3), replacing the n−6 PUFA linoleic acid (18∶2n−6) and arachidonic acid (20∶4n−6) over the dosage range. There was no difference in KCl-induced depolarization-driven contractility. However, a significant increase in receptor-dependent maximal contractility occurred at 1% FO for carbachol and at 2.5% FO for prostaglandin E₂, with a concomitant increase in sensitivity for prostaglandin E₂ at 2.5 and 5% FO. These results demonstrate that significant increases in ileal membrane n−3 PUFA occurred at relatively low doses of dietary FO, with differential receptor-dependent increases in contractility observed for muscarinic and prostanoid agonists.     

Distribution of polyunsaturated fatty acids including conjugated linoleic acids in total and subcellular fractions from healthy and cancerous parts of human kidneys

Differences in the FA composition of subcellular fractions from healthy and cancerous kidney tissues from the same patients were examined. Only minor differences in CLA content were found between the healthy and the cancerous tissue portions. Regarding the distribution pattern, CLA incorporation into nuclei and cytosol was significantly higher than incorporation into plasma membranes and mitochondria, which could be correlated to the neutral lipid content of these fractions. The subcellular distribution pattern of CLA was similar to that observed with monounsaturated FA but unlike that found with 18∶2n−6, which underlines the different physiological properties of CLA and 18∶2n−6. Because PUFA have been suggested to have an effect on cancer risk, the contents of n−3 and n−6 PUFA were determined in kidney and renal cell carcinoma (RCC). The 18∶2n−6 content and Δ⁵ desaturase activity were significantly lower, and the 18∶3n−6, 20∶3n−6, and 20∶5n−3 contents and Δ⁶ desaturase activity were significantly higher in RCC than in healthy renal tissue, indicating a changed PUFA metabolism in RCC. Previous research has suggested that CLA inhibits the elongation and desaturation of 18∶2n−6 into 20∶4n−6. In that case, one might speculate that a diet enriched in CLA would be a useful tool in preventing RCC. However, the involvement of CLA in preventing renal cancer could not be demonstrated definitively from the design of this experiment. Further understanding of the cause and/or consequence of the difference in FA metabolism may lead to a better understanding of RCC.     

Plasma lipids and fatty acids in urbanized Bushmen,Hereros and Kavangos of Southern Africa (Namibia)

Thirty-nine urbanized ethnic Namibian people comprising 21 Bushmen (semi-urbanized), 7 Hereros and 11 Kavangos were assessed for plasma lipids and fatty acid (FA) composition. Total cholesterol and triacylglycerol concentrations were measured by enzymatic methods, and neutral lipid FA composition by gas-liquid chromatography. The results demonstrated that while total cholesterol concentrations were not significantly different, significant differences in triacylglycerol concentrations (P<0.05) were seen between Bushmen and Kavangos. By comparing Bushmen with Hereros and Kavangos, significant differences between Bushmen and Kavangos were also observed in plasma triacylglycerol FA compositions, particularly 16∶0 (32.73%vs. 25.05%), 16∶1n−7 (7.00%vs. 5.06%), 18∶2n−6 (9.30%vs. 22.25%) and 20∶3n−6 (0.12%vs. 0.48%), while Kavangos had higher 20∶4n−6 levels than Hereros (1.44%vs. 2.00%). In plasma cholesteryl esters, Bushmen were significantly different from Kavangos in 16∶1n−7 (8.85%vs. 4.93%), 18∶1n−9 (32.06%vs. 23.07%) and 20∶4n−6 (6.91%vs. 10.00%). Significant differences were also observed between Bushmen and Hereros in 18∶0 (1.08%vs. 1.29%) and 18∶2n−6 (35.68%vs. 45.50%). The FA of Namibian groups were also compared with South African reference groups comprising urbanized whites and Xhosas and rural Vendas. The differences in blood lipid values can be explained primarily by excessive alcohol consumption. These results suggest that semi-urbanized Bushmen have changed their diets under urbanized conditions which may increase their risk of coronary heart disease.     

FA composition of plasma,red blood cell,and liver phospholipids of newborn piglets fed trans isomers of alpha-linolenic acid

The effects of dietary cis and trans α-linolenic acid (18∶3n−3) on the FA composition of plasma, red blood cell, and liver phospholipids were studied in newborn piglets. Animals were fed for 14 d with one of three diets: a control diet (group A) containing cis 18∶3n−3 at a level of 2.0% of total FA, a diet (group B) in which a part of the 18∶3n−3 acid was isomerized (1.3% of cis 18∶3n−3 and 0.7% of trans 18∶3n−3), or a diet (group C) with 2.0% cis 18∶3n−3 and 0.7% trans 18∶3n−3. Feeding animals with diets containing trans 18∶3n−3 resulted in the presence of trans isomers of 18∶3n−3, trans isomers of EPA, and trans isomers of DHA in phospholipids; however, the level of total trans n−3 PUFA in tissues was less than 0.3% of total tissue FA. In group B, the reduction of dietary amounts of cis 18∶3n−3 was associated with a decrease in individual and total cis n−3 PUFA. In contrast, in group C there was no decrease in tissue n−3 PUFA despite the increased dietary level of trans 18∶3n−3. These results suggest that the isomerization of a part of dietary n−3 PUFA, leading to the reduction of their levels in the diet, could induce a decrease in n−3 PUFA in phospholipids. The physiological effects of trans PUFA are not known and should be considered in future studies.     

Influence of diet on fatty acids of three subtropical fish, subfamily caesioninae (Caesio diagramma and C. tile) and family siganidae (Siganus canaliculatus)

The total lipid and fatty acid compositions of tissues and the stomach contents of three subtropical marine fish species, subfamily Caesioninae, Caesio diagramma and C. tile, and family Siganidae Siganus canaliculatus, were investigated to clarify the differences between these species. Triacylglycerols (TAG) were the dominant depot lipids of the three species, whereas wax esters were found as a minor component. In particular, muscle lipids were found to contain mainly glycerol derivatives such as TAG and phospholipids. The major fatty acids identified in the three species were 16∶0, 18∶0, 18∶1n−9, and 22∶6n−3 (docosahexaenoic acid, DHA). In addition, noticeable levels of 16∶1n−7, 18∶1n−7, 20∶4n−6 (arachidonic acid, AA), and 20∶5n−3 (eicosapentaenoic acid) were found. DHA was the most abundant polyunsaturated fatty acid (PUFA) in the muscle and viscera lipids of the three species. The high DHA levels in the lipids of all the organs were found to be higher than those of the lipid extracted from the stomach contents of the three fishes. In addition, the specimens of S. canaliculatus contained significantly higher levels of AA in its tissues than did the other two species. A high AA content is unusual since such high levels of n−6 PUFA are rarely found in higher marine organisms. These levels may be due to its characteristic feeding pattern, because S. canaliculatus prefer and mainly feed on seaweed, which often contains high amounts of n−6 PUFA, such as linoleic acid (18∶2n−6) and AA.     

Phospholipid fatty acyl distribution of three fungi indicates positional specificity for n-6vs. n-3 fatty acids

Phospholipids of the fungiConidobolus nanodes, Entomophthora exitalis andSaprolegnia parasitica were extracted and analyzed. The phospholipid content was the same (2.4%) for the three species and was independent of the total lipid content. Phospholipase A₂ degradation of individual phospholipid classes showed an asymmetrical distribution of polyunsaturated fatty acids (PUFA) between the two fatty acyl positions of glycerol. There was a predominance of n-6 PUFA at position 2 and a predominance of n-3 PUFA at position 1. WithC. nanodes andE. exitalis, 20∶5n−3 is derived from 18∶3n−3 and is located predominantly at position 1. InS. parasitica 20∶5n−3 is synthesized from 18∶3n−6via 20∶4n−6 and is located predominantly at position 2. It is suggested that the asymmetrical distribution of PUFA between positions 1 and 2 of glycerol Points towards different sites of synthesis of the two classes of PUFA, and that cross-over between PUFA of the different types is prevented by thesn-1 orsn-2 positional specificity of the desaturases.     

Incorporation of n−3 fatty acids into plasma and liver lipids of rats: Importance of background dietary fat

The health benefits of long-chain n−3 PUFA (20∶5n−3 and 22∶6n−3) depend on the extent of incorporation of these FA into plasma and tissue lipids. This study aimed to investigate the effect of the background dietary fat (saturated, monounsaturated, or n−6 polyunsaturated) on the quantitative incorporation of dietary 18∶3n−3 and its elongated and desaturated products into the plasma and the liver lipids of rats. Female weanling Wistar rats (n=54) were randomly assigned to six diet groups (n=9). The fat added to the semipurified diets was tallow (SFA), tallow plus linseed oil (SFA-LNA), sunola oil (MUFA), sunola oil plus linseed oil (MUFA-LNA), sunflower oil (PUFA), or sunflower oil plus linseed oil (PUFA-LNA). At the completion of the 4-wk feeding period, quantitative FA analysis of the liver and plasma was undertaken by GC. The inclusion of linseed oil in the rat diets increased the level of 18∶3n−3, 20∶5n−3, and, to a smaller degree, 22∶6n−3 in plasma and liver lipids regardless of the background dietary fat. The extent of incorporation of 18∶3n−3, 20∶5n−3, and 22∶5n−3 followed the order SFA-LNA>MUFA-LNA>PUFA-LNA. Levels of 22∶6n−3 were increased to a similar extent regardless of the type of major fat in the rat diets. This indicates that the background diet affects the incorporation in liver and plasma FA pools of the n−3 PUFA with the exception of 22∶6n−3 and therefore the background diet has the potential to influence the already established health benefits of long-chain n−3 fatty acids.     

Lipid class distribution of fatty acids including conjugated linoleic acids in healthy and cancerous parts of human kidneys

In this study the FA compositions of healthy and cancerous human renal tissues from the same patients are compared with special reference to the CLA and PUFA content. CLA was preferentially incorporated into neutral lipid compared with phospholipid classes. Its distribution profile was similar to that of monounsaturated FA, but unlike that found with 18∶2n−6. Different incorporation patterns were found for individual CLA isomers. Comparing renal cell carcinoma (RCC) and healthy kidney, the total CLA content was significantly lower in the cholesterylester fraction and significantly higher in the PE and PS fractions from RCC. The most significant differences between healthy and cancerous renal tissue were in the content of t10,c12-CLA. Furthermore, the lipid class distributions of n−6 PUFA were determined, and several significant differences between RCC and healthy renal tissue were found. This is of interest, as it has been proposed that the anticarcinogenic properties of dietary CLA are associated with their interference in the metabolism of 20∶4n−6. The involvement of CLA in preventing renal cancer cannot be definitively demonstrated from the design of this study, nor was it intended, but the complete determination of the FA composition of adjacent healthy and cancerous tissues may provide an insight if lipids are involved in this disease.     

Dietary fatty acids,membrane transport,and oxidative sensitivity in human erythrocytes

This study examined effects of dietary n−3 fatty acids on age-related changes in erythrocyte anion transport and susceptibility to oxidation. Blood was drawn from healthy adult volunteers before and after six weeks' supplementation (nine/group) with 4.0 g/day of safflower oil (containing 2.9 g n−6 fatty acids) or fish oil (containing 1.2 g long-chain n−3 fatty acids). Following density separation of young and old erythrocytes, membrane anion transport and cell membrane lipid composition were measured. Oxidative damage was measured in erythrocyte ghosts exposed to a free radical generator. Fish oil significantly increased 16∶0 and 20∶5n−3 in ghosts of both young and old cells, and 22∶5n−3 and 22∶6n−3 in old cells alone. Safflower oil increased 16∶0, 18∶0, 18∶1n−9, and 22∶5n−6 in ghosts of young cells only. The age-dependent increase in membrane anion transport (P<0.01) was decreased by dietary fish oil supplementation, but not by safflower oil supplementation. Safflower oil and fish oil increased the susceptibility of both young and old erythrocytes to oxidative damage by free radical generation (P<0.001).     

Isomers of hexadecenoic and hexadecadienoic acids in <Emphasis Type="Italic">Androsace septentrionalis</Emphasis> (Primulaceae) seed oil

Seeds of Androsace septentrionalis of the genus Androsace (tribus Primuleae) from the plant family Primulaceae were studied for their oil content and FA composition. The seed oil of A. septentrionalis was found to contain two unusual FA rarely occurring in plants: 11-cis-hexadecenoic acid (16∶1Δ11c or 16∶1n−5) and 9-cis,12-cis-hexadecadienoic acid (16∶2Δ9c,12c or 16∶2n−4). It also contained an unusually high amount (21.4%) of 9-cis-hexadecenoic acid (palmitoleic acid; 16∶1Δ9c or 16∶1n−7), i.e., at a level higher than that of oleic acid, in addition to common FA. Compared with most plant seed oils, at 3.8% the level of 18∶1Δ11c (or 18∶1n−7) also was elevated. The nonidentity of the Androsace 16∶2-acid with the 16∶2-acid, which is very typical for Ranunculus spp., as well as its identity with the 16∶2-acid typically found in Asclepiadaceae was established by co-chromatography. The structure and composition of the constituent FA of A. septentrionalis were also determined by various chromatographic methods (TLC, Ag⁺-TLC, capillary GLC) and spectroscopic methods (IR, GC-MS). The significant deviation of the Androsace FA pattern from that of other Primuleae, indicating a separate phylogenetic position of Androsace, is discussed.     

Effects of feeding Lunaria oil rich in nervonic and erucic acids on the fatty acid compositions of sphingomyelins from erythrocytes, liver, and brain of the quaking mouse mutant

Feeding an oil from Lunaria biennis rich in 22∶1n−9 and 24∶1n−9 to homozygous quaking (qk.qk) mice caused a large increase in the percentage of 24∶1n−9 and corresponding decreases in the percentage of 24∶0 and 22∶0 in sphingomyelins from liver, erythrocytes, and milk. Brain sphingomyelin from 2-wk-old qk.qk pups born to qk.qk mothers maintained on the Lunaria oil had essentially normal percentage of 24∶1n−9 and 18∶0, in contrast to pups born to mothers maintained on a control oil rich in 18∶1n−9 whose brain sphingomyelin had a markedly reduced percentage of 24∶1n−9 and an increased percentage of 18∶0. After 2 wk and up to and beyond weaning, the qk.qk pups from Lunaria-fed mothers weaned on to the Lunaria diet had a markedly decreased percentage of 24∶1n−9 in their brain sphingomyelin, accompanied by an increased percentage of 18∶0, as compared to heterozygous quaking mice. However, the percentage of 24∶1n−9 in brain sphingomyelin in qk.qk pups weaned on to the Lunaria diet continued throughout this period (2–8 wk postbirth) to be significantly higher than in qk.qk pups weaned on to the control diet. We conclude that dietary 24∶1n−9 influences the fatty acid composition of brain sphingomyelin in qk.qk mice, but only via the mother in pre- or early postnatal animals. We further consider that the dietary effects may be elicited mainly in the sphingomyelin of nonmyelinated brain cells, and that the nervonic acid in myelin sphingomyelin may be formed mainly by chain elongation in oligodendrocytes from shorter chain fatty acid precursors.     

The Effects of dietary n−3/n−6 ratio on brain development in the mouse: a dose response study with long-chain n−3 fatty acids

This study examines the effects of the ratio of n−3/n−6 fatty acids (FA) on brain development in mice when longchain n−3 FA are supplied in the diet. From conception until 12 days after birth, B6D2F₁ mice were fed liquid diets, each providing 10% of energy from olive oil, and a further 10% from different combinations of free FA concentrates derived from safflower oil (18∶2n−6), and fish oil (20∶5n−3 and 22∶6n−3). The range of dietary n−3/n−6 ratios was 0,025, 0.5, 1.0, 2.0, and 4.0, with an n−6 content of greater than 1.5% of energy in all diets, and similar levels of total polyunsaturated fatty acids (PUFA). In an additional group of ratio 0.5, 18∶2n−6 was partially replaced by its δ6 desaturation product, 18∶3n−6. Biochemical analyses were conducted on 12-day-old pup brains, as well as on samples of maternal milk. No obvious effects on overall pup growth and development were observed, apart from a smaller litter size at ratio 1. Co-variance analysis indicated that increasing the n−3/n−6 ratio was associated with slightly smaller brains, relative to body weight. We found that 18∶2n−6 and 20∶5n−3 were the predominant n−6 and n−3 FA in the milk; in the brain these were 20∶4n−6 and 22∶6n−3, respectively. Increasing dietary n−3/n−6 ratios generally resulted in an increase in n−3 FA, with a corresponding decrease in n−6 FA. The n−3/n−6 ratio of the milk lipids showed a strong linear relationship with the diet, but in the brain the rate of increase tended to decrease beyond 0.5 (phosphatidylcholine, PC) and 0.25 (phosphatidylethanolamine, PE), such that there was a significant quadratic contribution to the relationship. The partial replacement of dietary 18∶2n−6 with 18∶3n−6 raised levels of 20∶4n−6 in milk, brain PC, and brain PE. These results indicate that the n−3/n−6 ratio of the phospholipids in the developing mouse brain responds maximally to maternal dietary long-chain n−3/n−6 ratios of between 0.25 and 0.5.