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1.
Several studies have reported that feeding γ-linolenic acid (GLA) has resulted in no increase in arachidonic acid (AA) in newborns. This result was ascribed to the eicosapentaenoic acid (EPA)-rich fish oil used in these formulas. Docosahexaenoic acid (DHA) sources with only minor amounts of EPA are now available, thus the addition of GLA to infant formulas might be considered an alternative to AA supplementation. Sixty-six premature infants were randomized to feeding one of four formulas [ST: no GLA, no long-chain polyunsaturated fatty acids; BO: 0.6% GLA (borage oil); BO + FOLOW: 0.6% GLA, 0.3% DHA, 0.06% EPA; BO + FOHIGH: 0.6% GLA, 0.3% DHA, 0.2% EPA] or human milk (HM, nonrandomized) for 4 wk. Anthropometric measures and blood samples were obtained at study entry and after 14 and 28 d. There were no significant differences between groups in anthropometric measures, tocopherol, and retinol status at any of the studied time points. The AA content of plasma phospholipids was similar between groups at study start and decreased significantly until day 28 in all formulafed groups, but not in the breast-fed infants [ST: 6.6±0.2%, BO: 6.9±0.3%, BO + FOLOW: 6.9±0.4%, BO + FOHIGH: 6.7±0.2%, HM: 8.6±0.5%, where values are reported as mean ±standard error; all formulas significantly different (P≤0.05) from HM]. There was no significant influence of GLA or fish oil addition to the diet. GLA had only a very limited effect on AA status which was too small to obtain satisfactory concentrations (concentrations similar to breast-fed babies) under the circumstances tested. The effect of GLA on AA is independent of the EPA and DHA content in the diet within the dose ranges studied.  相似文献   

2.
Fatty acid compositions of crude melon seed oil from two different sources were compared. Melon seeds fromCitrullus vulgaris (syn.C. lanatus) contained phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and phosphatidylserine (PS), whereas melon seeds fromCitrullus colocynthis contained only PC and LPC, but not PS. Analysis of the total lipids revealed that the major fatty acid of the oils was 18:2n-6.Citrullus vulgaris seed oil contained 71.3% andC. colocynthis contained 63.4% of 18:2n-6. The predominant fatty acids in theC. vulgaris PC were 18:2n-6 (32.2%), 18:1n-9 (26.4%) and 16:0 (22.2%), whereas theC. colocynthis PC contained 44.6% of 18:1n-9 as the major fatty acid. The level of monoenes in theC. colocynthis variety (46.2%) was different from theC. vulgaris (27.3%). The major fatty acid in the LPC was 18:1n-9 for both varieties. Notably, theC. colocynthis variety did not contain any PS. The major fatty acids in theC. vulgaris PS were 18:1n-9 (37.9%) and 18:2n-6 (33.7%). Of all the phospholipids, LPC contained the greatest amount of monoenes, 48.6–52.4%.  相似文献   

3.
Male Wistar rats were fed rapeseed oil containing high or low levels or erucic acid for 20 weeks, and changes in the fatty acid composition of cardiac mitochondrial phospholipids were studied. Treatment with rapeseed oil containing 46.2% erucic acid showed incorporation of 22∶1 (5.6%) into isolated cardiolipin from heart mitochondria. After high or low (3.7%) erucic rapeseed oil feeding, linoleic acid was slightly incorporated into cardiolipin. Moreover, both of these rapeseed oils induced a significant increase of linoleate-arachidonate ratio in phosphatidylethanolamine and phosphatidylcholine. This ratio was also significantly increased in fatty acids esterified to the β-position of these phospholipids. On the basis of such results, we have to consider the role of linolenic acid which is present at a high level in the different rapeseed oils used, as a possible inhibitor of heart microsomal enzymes involved in linoleate arachidonate conversion. Such alterations might account for mitochondrial fragility and myocardial lesions obtained in long term rapeseed oil feeding experiments. ERA-CNRS no 070497  相似文献   

4.
The γ-linolenic acid (Z,Z,Z-6,9,12-octadecatrienoic acid, GLA) present in borage oil free fatty acids was concentrated in esterification reactions that were catalyzed by several preparations of the acyl-specific lipase ofGeotrichum candidum. In this manner, a 95% recovery of the GLA originally present in borage oil (25% GLA) was obtained as a highly enriched fatty acid fraction with a GLA content of >70%. Other fatty acids concentrated in this fraction were the monounsaturated fatty acids with chainlengths of C-20 and longer that were present in the oil. An immobilized preparation ofG. candidum on silica gel also was used for the enrichment of GLA in borage oil. In this instance, a 75% recovery of GLA was obtained, and the supported lipase was reusable (three cycles) with minimal loss in activity. Presented in part at the 84th Annual Meeting of the American Oil Chemists’ Society, Anaheim, California, May 1993.  相似文献   

5.
The effect of supplementation with borage oil containing γ-linolenic acid (GLA, 18∶3n−6) on the levels and fattya cid compositions of individual human platelet phospholipids was evaluated. For this purpose, male volunteers were given an average daily intake of 5.23 g of GLA (as borage oil) for 42 days, after which the supplement was withdrawn for an additional 42-day period. No significant differences were found in the relative amounts of the choline phospholipids (PC), ethanolamine phospholipids (PE), phosphatidylserine (PS), phosphatidylinositol (PI), and sphingomyelin (SPH) at days 0, 22, 43, 64, and 85. However, marked differences were observed in the fatty acid compositions of all the phospholipids including a marked, and reversible, rise in the level of dihomo-γ-linolenic acid (DGLA, 20∶3n−6), without a significant elevation in arachidonic acid (AA, 20∶4n−6) and decreases in n−3 polyunsaturated fatty acids. In the case of PC, a net rise in DGLA of 1.8 mol% was observed by day 22 (from 2.1 to 3.9 mol%). The DGLA/AA ratios at day 43 exhibited considerable variability across phospholipids with PC>PS>PE=PI; the PC, PE, PS, and PI accounted for 67.6, 16.7, 12.9, and 2.6%, respectively, of the total DGLA in platelet phospholipids. Interestingly, despite the lack of DGLA in SPH, this phospholipid exhibited a marked enrichment in nervonic acid (NA, 24∶1n−9) from 16.2 to 24.7 mol% upon borage oil consumption. The observed alterations may represent biochemical strategies for adaptation to dietary fatty acid modifications and the regulation of platelet membrane functioning.  相似文献   

6.
Boars fed diets containing rapeseed oil for 8 weeks showed significantly higher levels of neutral lipids and similar levels of phospholipids, compared to those fed corn oil. Erucic and eicosenoic acids were found to be high in ethanolamine phosphoglycerides, and in particular alkenyl acyl-ethanolamine phosphoglyceride. Furthermore, both long chain monoenes were incorporated preferentially in position 2 of the choline and ethanolamine phosphoglycerides. The alkenyl group composition of the cardiac lipids of pigs was influenced by dietary fatty acids. When rapeseed oil was fed, small amounts of 20∶1 and 22∶1 alkenyl constituents were detected. Contribution No. 641 Animal Research Institute  相似文献   

7.
The fatty acid composition (% by wt) of Tamarind (Tamarindus indica) kernel oil, as determined by gas liquid chromatography was: trace lauric acid, tracte myristic acid, 14.8% palmitic acid, 5.9% stearic acid, 27.0% oleic acid, 7.5% linoleic acid, 5.6% linolenic acid, 4.5% arachidic acid, 12.2% behenic acid, and 22.3% lignoceric acid.  相似文献   

8.
Fatty acid composition of thirty-five Icelandic fish species   总被引:1,自引:0,他引:1  
Fat content and fatty acid composition were determined in 35 fish species caught in Icelandic waters from November 1987 to March 1988. These were not only commonly edible species, but also underutilized and less common species, in which the fatty acid composition have not been reported before. The variation int he fat content and the fatty acid composition was found to be large between and within species. The fat content and n-3 fatty acid content varies sevenfold and twentyfold, respectively. An inverse relationship was obtained between the n-3 fatty acids content and the total fat content of the fish species studied. We believe that the data reported here on 35 fish species can be useful for nutritionists and food scientists, to aid them in dietary formulation, nutrient labelling, processing and product developments, as well as for the consumers.  相似文献   

9.
The incorporation of vaccenic acid (VA, 0.5 and 1.2%), conjugated linoleic acid (CLA, mixture of primarily c9,t11‐ and t10,c12‐CLA, 1.2%), linoleic acid (LA, 1.2%) and oleic acid (OA, 1.2%) into different tissues of mice was examined. The effects on the fatty acid composition of triacylglycerols (TAG) and phospholipids (PL) in kidney, spleen, liver and adipose tissue were investigated. VA and CLA (c9,t11‐ and t10,c12‐CLA) were primarily found in TAG, especially in kidney and adipose tissue, respectively. Conversion of VA to c9,t11‐CLA was indicated by our results, as both fatty acids were incorporated into all the analyzed tissues when a diet containing VA but not c9,t11‐CLA was fed. Most of the observed effects on the fatty acid profiles were seen in the CLA group, whereas only minor effects were observed in the VA groups compared with the OA group. Thus, CLA increased n‐3 polyunsaturated fatty acids (PUFA) in PL from kidney and spleen and lowered the ratio of n‐6/n‐3 PUFA in these tissues. Furthermore, CLA increased C22 PUFA in the PL fraction of kidney, spleen and liver, but reduced the level of arachidonic acid in PL of liver and spleen and lowered the Δ9‐desaturation indexes in all analyzed tissue TAG.  相似文献   

10.
Fatty acids of the individual phospholipids and total neutral lipid fractions in skeletal muscle of three species of Arctic mice were identified and quantitated after the mice had been classified as control, cold-sensitive or cold-resistant. The results indicate that some species increase the percentage of unsaturated fatty acids as an apparent result of cold exposure and some species do not. A common finding for all cold-sensitive mice was a significant increase in 14∶0 in phosphatidic acid when compared to cold-resistant and control animals. Hypotheses are presented in an attempt to explain this finding.  相似文献   

11.
The metabolism of α-linolenic acid from canola oil was studied in eight normolipidemic men. The 42-day study was divided into three periods: a 6-day pre-experimental and two 18-day experimental. Approximately 75% of the dietary fat (28% of total energy) was provided by a mixture of fats during the pre-experimental period and either canola oil (CO) or sunflower oil (SO) during the experimental periods. The CO and SO diets were fed in a cross-over design. The ratios of linoleic to linolenic acid were 2.6∶1 and 73.9∶1 in the CO and SO diets, respectively. Dietary fat source had an effect on plasma phospholipid fatty acids: 18∶1n−9, 18∶3n−3 and 20∶5n−3 were higher (p<0.05), and 18∶2n−6 was lower in the phosphatidylcholine fraction; 18∶1n−9 was higher and 20∶4n−6 lower in the phosphatidyl-ethanolamine fraction; and 18∶1n−9 and 20∶5n−3 were higher and 20∶4n−6 and 22∶6n−3 were lower in the alkenylacyl-ethanolamine phospholipid fraction on the CO diet as compared to the SO diet. Consumption of the canola oil diet resulted in higher n−3 fatty acid levels and lower n−6 fatty acid levels in plasma phospholipids than consumption of the sunflower oil diet.  相似文献   

12.
13.
Nine healthy male volunteers were given 15 Max EPA fish oil capsules providing 2.67 g of eicosapentaenoic acid (EPA, 20∶5ω3) and 1.72 g of docosahexaenoic acid (DHA, 22∶6ω3) daily for 3 wk. Measurements were taken at baseline, at the end of the fish-oil period, and at 2 and 6 wk postsupplementation. The effect of fish oil on plasma lipids and the fatty acid composition of individual platelet phospholipids was studied. In general, the proportions of 20∶5ω3 and 22∶6ω3 in platelet phosphoglycerides were substantially increased mainly at the expense of arachidonic acid (AA, 20∶4ω6). A large and significant increase in the relative EPA content of phosphatidylcholine (PC) (P<0.001) and phosphatidylethanolamine (PE) (P<0.001) was noted at the end of the 3 wk supplementation. We have also shown for the first time a small but significant (P<0.001) incorporation of EPA in phosphatidylserine (PS). Incorporation of DHA was also detected in PC, PE and PS, whereas the relative AA content of these phospholipids was significantly reduced. Fish oil supplementation led to a significant increase of 22∶5ω3 in PS and decreases of 20∶3ω6 in PC and 22∶4ω6 in PE. Postsupplementation measurements showed a gradual return of all fatty acids to baseline levels. The fatty acid composition of the phosphatidylinositol (PI) fraction remained unchanged throughout the trial period. We conclude that in humans ω3 fatty acids are incorporated into platelet membrane phospholipid subclasses with a high degree of specificity.  相似文献   

14.
Utilization of enteral feeding modalities may prove clinically relevant for rapid modulation of lung phospholipid polyunsaturated fatty acids (PUFA) that serve as substrates for the formation of vasoactive dienoic eicosanoids. We compared the effects of short-term enteral feeding with formulations enriched with either fish (n−3) or corn (n−6) oil PUFA on the fatty acid composition of rat lung, alveolar macrophage and surfactant phospholipids. The diets were infused continuously for 72 h through a surgically placed gastroduodenal feeding catheter by a syringe pump. The n−3 PUFA derived from the fish oil enriched diet were readily incorporated into the phospholipid membranes of the alveolar macrophages, lung tissue and pulmonary surfactant. The relative percentages of the n−3 PUFA were significantly higher and individual and total n−6 PUFA significantly lower in the macrophage, lung and surfactant phospholipids from the n−3-supplemented rats in comparison with those present in the rats infused enterally with the n−6 diet or untreated, chow-fed rats (baseline). In contrast, there was a significant increase in linoleic acid (18∶2n−6) without modification of arachidonic acid (20∶4n−6) in the alveolar macrophages, lung tissue and surfactant from rats enterally receiving the n−6 diet relative to levels measured in the rats at baseline. The results suggest that short-term continuous delivery of n−3-enriched enteral preparations can foster rapid modification of membrane phospholipid PUFA composition of lung tissue, alveolar macrophages and lung surfactant. Utilization of similar infusion modalities to deliver n−3-enriched enteral formulations may prove beneficial to critically ill or postoperative patients with persistent lung inflammation secondary to uncontrolled formation of vasoactive eicosanoids derived from arachidonic acid.  相似文献   

15.
Feeding rats diets containing brominated corn oil or di- or tetrabromostearate as the monoglyceride produced changes in fatty acid composition of liver lipids. Those changes associated with the feeding of brominated corn oil or tetrabromosterates could be explained by the accumulation of triglyceride, and the changes associated with the feeding of dibromostearate could result from the proliferation of a membrane system. A unique response to the feeding of diets containing brominated corn oil is an increase in the level of γ-linolenic acid.  相似文献   

16.
The fatty acid composition of total phospholipids in different regions, viz., cerebrum, cerebellum and medulla oblongata, of developing human fetal brain was studied. All the brains analyzed in the present investigations were obtained from fetuses whose mothers belonged to the poor socioeconomic section of the population. Palmitic, oleic and stearic acids were found to be the dominant fatty acids, and the pattern was similar in all regions of the brain studied between the ages of 22 and 35 weeks. However at birth there appeared to be an increase in polyenoic acids at the expense of lower chain fatty acids, and these changes were of relatively higher magnitude in the cerebellum than in other regions studied. These changes, in terms of increase in polyunsaturated fatty acids near full term, coincided well with the already observed timing of an overall growth spurt of the brain a few weeks preceding birth.  相似文献   

17.
Acetylation of fatty acid methyl esters from castor oil makes possible accurate determination of all components in a single run by gas-liquid chromatography with butanediol succinate as the stationary phase.  相似文献   

18.
Lipase-catalyzed acidolysis of acylglycerols of borage (Borago officinalis L.) oil with a docosahexaenoic acid (DHA) concentrate, prepared from algal oil, in organic solvents was studied. Seven lipases were used as biocatalysts for the acidolysis reaction. Novozyme 435 from Candida antarctica, as compared to lipases from Mucor miehei and Pseudomonas sp., showed the highest degree of DHA incorporation into borage oil. Other lipases tested, such as those from Aspergillus niger, C. rugosa, Thermomyces lanuginousus and Achromobacter lunatus, were rather ineffective in the incorporation of DHA into borage oil. Effects of variation of reaction parameters, namely, enzyme load, temperature, time course, and type of solvent, were monitored for C. antarctica as the biocatalyst of choice. Incorporation of DHA increased with increasing amount of enzyme, reaching 27.4% at an enzyme concentration of 150 lipase activity units. As incubation time progressed, DHA incorporation also increased. After a reaction time of 24 h, the contents of total n-6 and n-3 polyunsaturated fatty acids in acylglycerols were 44.0 and 27.6%, respectively. The highest degree of DHA incorporation was achieved when hexane was used as the reaction medium. The positional distribution of DHA in modified borage oil was determined using pancreatic lipase hydrolysis. Results showed that DHA was randomly distributed over the sn-1, sn-2, and sn-3 positions of the triacylglycerol. Thus, preparation of modified borage oil acylglycerols containing both DHA (22:6n-3; 27.4%) and γ-linolenic acid (18:3n-6; 17.0%) was successfully achieved and products so obtained may have beneficial effects beyond simple physical mixtures of the two oils. The final oil had a ratio of n-3 to n-6 of 0.42–0.62 which is nutritionally more suitable than the original unaltered borage oil.  相似文献   

19.
The two major phospholipid classes, namely, phosphatidylethanolamines (PE) and phosphatidylcholines (PC), were studied in four different regions of human brain,i.e., in frontal gray matter, frontal white matter, hippocampus and in pons. The fatty acid (FA) compositions of these phospholipids were found to be specific for the different regions. PC contains mostly saturated and 18∶1 FA, while PE is rich in polyunsaturated FA. Aging has no influence on the FA compositions, while in Alzheimer’s disease (AD) PE is modified in all four regions, particularly in frontal gray matter and in hippocampus. The abundance of the major monounsaturated FA of PE, 18∶1, is not significantly altered in Alzheimer’s disease, but there is a substantial increase in the relative amounts of the saturated components 14∶0, 16∶0 and 18∶0. This is paralleled by a decrease in the polyunsaturated FA 20∶4, 22∶4 and 22∶6. It is not clear whether the changes observed are specific for AD. Changes in saturated/polyunsaturated FA ratio are likely to influence cellular function, which in turn may cause certain neural deficiencies. The findings do not support the hypothesis that AD reflects an accelerated aging process.  相似文献   

20.
The fatty acid compositions of muscle tissue taken from wild strains of pintado (Pseudoplatystoma corruscans) and pacu (Piaractus mesopotamicus) fish, which were taken from the Brazilian Pantanal, were compared to the fatty acid compositions of tissue taken from two corresponding cultivated strains, which were fed commercial diets. The cultivated species possessed lipid contents of 12.2% (pacu) and 8.9% (pintado) while the wild species contained 7.9% (pacu) and 2.5% (pintado) lipids. Despite the high lipid contents of the cultivated pintado and pacu, the n‐3 polyunsaturated fatty acid concentrations in muscle tissue were higher in wild pintado (224.9 mg/g flesh) and wild pacu (485.1 mg/g flesh) than in their respective cultivated strains (129.8 and 106.1 mg/g flesh, respectively). The n‐6/n‐3 ratios of pacu were 1.2 (wild) and 9.8 (cultivated), and those of pintado were 1.0 (wild) and 7.3 (cultivated). The fatty acid composition of pacu and pintado are strongly influenced by habitat and diet.  相似文献   

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