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1.
The deposition oftrans-12-octadecenoate-12(13)-3H (12t-18∶1-3H) was compared tocis-9-octadecenoate-10-14C (9c-18∶1-14C) in the major egg yolk neutral lipids and phospholipids.trans-12-Octadecenoate was preferentially incorporated into cholesteryl esters (CE), phosphatidylcholines (PC), and phosphatidylethanolamines (PE) but was discriminated against in triglycerides (TG). Isotopic ratios indicate that 5.9 and 5.6 times more 12t-18∶1-3H than 9c-18∶1-14C was esterified at the 1-acyl position of PE and PC, respectively. The combined 1- and 3-acyl positions of TG and the 2-acyl position of TG, PE and PC were each preferentially esterified with 9c-18∶1-14C.  相似文献   

2.
Mixtures of deuterium-labeledtrans-8-,cis-8- andcis-9-octadecenoic acids (8t–18∶1, 8c–18∶1, 9c–18∶1) were fed as triglycerides (TG) to two adult male subjects. Blood samples were collected sequentially over a 48-hour period. Plasma and lipoprotein lipids were separated by thin layer chromatography and analyzed by gas chromatography-mass spectroscopy. Results indicate (i) absorption of the 8t- and 8c–18∶1 isomers were similar to 9c–18∶1; (ii) the 8t–18∶1 isomer was cleared approximately 30% faster than 9c–18∶1 from plasma TG; (iii) cholesterol ester samples contained 8.4 times less 8t–18∶1 than 9c–18∶1; (iv) incorporation at the 1-acyl phosphatidylcholine (PC) position was higher for 8t–18∶1 and 8c–18∶1 (2.2 and 1.7 times) than for 9c–18∶1; and (v) discrimination at the 2-acyl PC position was 4.6-fold against 8t–18∶1 and 1.3-fold against 8c–18∶1 compared with 9c–18∶1. Discrimination against uptake of the Δ-8 isomers in both neutral and phospholipid classes suggests that both 8t- and 8c–18∶1 may be preferentially oxidized relative to 9c–18∶1. Except for triglycerides, data for each of the lipid classes from total plasma and individual lipoprotein samples were similar. These data indicate that differences for incorporation and turnover of the 8t- and 8c–18∶1 isomers relative to 9c–18∶1 are not substantially influenced by the lipoprotein classes. The maximum isotopic enrichment detected in the chylomicron triglycerides fractions was 60%, which indicates that a substantial amount of endogenous triglycerides was mobilized during absorption of the deuterated fats.  相似文献   

3.
Metabolism of linoleate versus linoelaidate in the laying hen   总被引:1,自引:0,他引:1  
The metabolic fate in the laying hen of linoelaidic acid, thetrans,trans-geometric isomer of linoleic acid, was compared to that of the naturally occurringcis,cis linoleate. In two experiments, mixtures of radioisotope-labeled linoleate and linoelaidate were orally administered to a set of three laying hens. A third mixture consisting of linoleate-3H and linoleate-14C was fed to three hens to measure biological isotope effects. Isotopic ratios (3H/14C) of the neutral lipid and phospholipid fractions isolated from egg yolks and of the octadecadienoic acids from these fractions were compared to those of the administered mixtures. The3H/14C ratiosindicate that linoelaidic acid and linoleic acid are equally incorporated into egg yolk neutral lipids and phospholipids. Arachidonic acid was found exclusively in the phospholipid fraction and was radiolabeled with the isotope from thecis,cis octadecadienoate isomer only. Further detailed analysis of individual neutral lipid components indicated: (a) discrimination against thetrans,trans isomer in cholesteryl esters and (b) no discrimination against either isomer in triacylglycerols. Presented at the AOCS Meeting, Chicago, September 1976.  相似文献   

4.
Triglycerides of deuterium-labeledtrans-11-,trans-11-cis-11- andcis-9-octadecenoic acid (11t-18∶1-2H, 11c-18∶1-2H) were simultaneously fed to two young adult male subjects. Plasma lipids from blood samples collected periodically for 48 hr were analyzed by gas chromatography-mass spectroscopy. The results indicate (i) the Δ11-18∶1-2H acids and 9c-18∶1-2H were equally well absorbed; (ii) relative turnover rates were higher for the Δ11-18-1-2H acids in plasma triglycerides; (iii) incorporation of the Δ11-18∶1-2H acids into plasma phosphatidylcholine was similar to 9c-18∶1-2H, but distribution at the 1-and 2-acyl positions was substantially different; (iv) esterification of cholesterol with 11t-18∶1 was extremely low; (v) chain shortening of the Δ11-18∶1-2H acids was 2–3 times greater than for 9c-18∶1-2H; (vi) no evidence for desaturation or elongation of the 18∶1-2H acids was detected; and (vii) a 40% isotopic dilution of the 18∶1-2H acids in the chylomicron triglyceride fraction indicated the presence of a substantial intestinal triglyceride pool. Based on our present knowledge, these metabolic results for Δ11-18∶1 acids present in hydrogenated oils and animal fats indicate that the Δ11 isomers are no more likely than 9c-18∶1 to contribute to dietary fat-related health problems.  相似文献   

5.
The syntheses of 15-tetracosynoic acid (ω9-tetracosynoic acid) and 19-octacosynoic acid (ω9-octacosynoic acid) are described. These alkynoic acids are to be tritiated to the corresponding alkenoic acids, which will be used as metabolic precursors of housefly pheromone components. The final step in each synthesis involved the coupling of 1-decyne to the lithio-salt of the appropriate ω-bromoacid. Homologation of dibromoalkanes was accomplished with triphasic catalytic displacement of bromide by cyanide ion. Oxidation of a bromo-alcohol to a bromoacid was performed in benzene with KMnO4 and 18-crown-6 ether. Mention of a company name or product in this paper does not imply endorsement by the U.S. Department of Agriculture.  相似文献   

6.
Lipids extracted from various tissues of four individual sunfish have been shown to contain thetrans-6-hexadecenoic acid previously reported for marine turtles, a metridium and a jelly fish, and also the 7-methyl-7-hexadecenoic acid recently isolated from one sunfish liver oil sample. The other fatty acids present were qualitatively typical of marine lipids in general. Unusual quantitative details included high percentages of 18∶0 and 20∶4ω6, which are also found in the Atlantic leatherback turtle and presumably linked to a similar diet of jellyfish and to other common factors. In a sample of lipids from intestinal contentstrans-6-hexadecenoic acid was found to be the predominant C16 monoene, and was accompanied by comparatively large amounts of the 7-methyl-7-hexadecenoic acid. This observation and other fatty acid details are compatible with an exogenous origin for these acids and jellyfish, etc., as a predominant dietary material for the ocean sunfish.  相似文献   

7.
A new approach describing the simultaneous extraction and preparative fractionation of egg yolk lipids is described, a method which can be extended to other tissues. In this method, egg yolk is adsorbed on activated thin layer chromatography grade silicic acid and sequentially extracted with different solvents to get a crude fractionation of its lipids into nonpolar and polar components. These crude concentrates help achieve larger yields of high purity lipids per unit column load during subsequent chromatographic subfractionation.  相似文献   

8.
Some characteristics of the fatty acid composition of animal tissue lipids are described and the origins of tissue fatty acids are discussed briefly. The effect of dietary fat on composition of tissue lipids is discussed. Types of dietary fatty acids for which experimental work is described include polyunsaturated fatty acids, short-chain fatty acids, fatty acids with chain length greater than C18,trans unsaturated fatty acids, fatty acids with conjugated double bonds, acetylenic fatty acids, branched-chain fatty acids and oxygenated fatty acids. The individuality of fatty acids is discussed in relation to their roles as components of tissue lipids.  相似文献   

9.
An experiment was carried out with laying hens in the age of 22—45 weeks to examine the effects of added soy oil (0%, 3.5%, 7%, 10.5%, and 14%) and dietary protein level (13.2% and 16.3%) on laying and reproductive performance, fatty acid composition of yolk fat, and other egg quality parameters. Moreover, digestibility of nutrients and of energy was determined by using a marker technique. Laying intensity and feed intake were not influenced by dietary treatments whereas egg weight and daily egg mass production were significantly improved by soy oil addition in a non‐linear related manner. The feed conversion ratio reached a minimum at soy oil proportions between 3.5% and 10.5%. Reproductive performance in terms of fertilized eggs, hatchability, and mortality of chicks was not affected by dietary treatments. The increase of egg weights due to soy oil addition was accompanied by a simultaneous increase in the proportion of albumen and a decrease of yolk and shell percentage. Palmitic acid (C16:0) and oleic acid (C18:1) proportions in yolk fat decreased as soy oil addition was increased whereas the proportions of linoleic acid (C18:2 n‐6), linolenic acid (C18:3 n‐3), and docosahexaenoic acid (C22:6 n‐3) were increased at the same time. Praecaecal digestibility of crude fat and fatty acids of the diets were non‐linearly improved by soy oil addition. Digestibility of crude protein and amino acids were not affected by either protein content of the diet or by soy oil supplementation. In conclusion, a decrease in dietary protein content from 16.3% to 13.2% did not negatively influence performance of hens and egg quality under the experimental conditions applied. Soy oil addition improved egg quality.  相似文献   

10.
Allylic amination of methyl oleate with bis(N-p-toluenesulfonyl) sulfodiimide results in a mixture of methyl 11-amino-(N-p-toluenesulfonyl)-9-E-octadecenoate and methyl 8-amino-(N-p-toluenesulfonyl)-9-E-octadecenoate in 58% yield. These novel products were isolated and characterized by nuclear magnetic resonance, infrared spectroscopy, mass spectrometry, and melting point. The reaction was analyzed by highperformance liquid chromatography and thin-layer chromatography.  相似文献   

11.
Oral administration of 1,2-propanediol to rats in a daily dose of 1 ml of 28.4% aqueous solution per 100 g body weight for 30 days caused a significant decrease in the total lipids, fatty acids, phospholipids, and triglycerides of plasma, liver, and heart, The cholesterol content in plasma decreased while that in the tissues increased significantly. The accumulation of cholesterol in tissues tends to discourage long term use of 1,2-propanediol even by the oral route.  相似文献   

12.
Derrick NM  Wishner LA 《Lipids》1967,2(2):133-136
Male weanling rats were fed vitamin E-deficient and vitamin E-supplemented diets containing 5% corn oil or cod-liver oil for 16 weeks, after which their adipose tissue lipids were extracted and analyzed in a nitrogen atmosphere for carbonyl compounds and fatty acids. The vitamin E-deficient cod-liver oil-fed rats, exhibiting incisor depigmentation and darkened adipose tissue, yielded lipids which had a lower iodine value, contained less polyunsaturated fatty acids, and contained more carbonyl compounds, particularly alkanals and alk-2-enals, than the lipids from the animals fed the vitamin E-supplemented cod-liver oil diet. The tissues of the vitamin E-deficient corn oil-fed rats contained less linoleate and more monocarbonyl compounds than those of the vitamin E-supplemented corn oil-fed animals. The results indicate that vitamin E protection is necessary for the incorporation of C20 and C22 fatty acids into the tissues from the diet and that in the deficiency of vitamin E, a low level of autoxidation occurs in the tissues.  相似文献   

13.
Fu Z  Attar-Bashi NM  Sinclair AJ 《Lipids》2001,36(3):255-260
A recent study on the metabolism of 1-14C-α-linolenic acid in the guinea pig revealed that the fur had the highest specific activity of all tissues examined, 48 h after dosing. The present study investigated the pattern of tissue lipid labeling following an oral dose of 1-14C-linoleic acid after the animals had been dosed for the same time as above. Guinea pigs were fed one of two diets with a constant linoleic acid content (18% total fatty acids) and a different content of α-linolenic acid (0.3 or 17.3%) from weaning for 3 wk and 1-14C-linoleic acid was given orally to each animal for 48 h prior to sacrifice. The most highly labeled tissues (dpm/mg of linoleic acid) were liver, followed by brain, lung and spleen, heart, kidney and adrenal and intestines, in both diet groups. The liver had almost a three-fold higher specific activity than skin and fur which was more extensively labeled than the adipose and carcass. Approximately two-thirds of the label in skin plus fur was found in the fur which, because of a low lipid mass, would indicate that the fur was highly labeled. All tissues derived from animals on the diet with the low α-linolenic acid level were significantly more labeled than the tissues from the animals on the high α-linolenic acid diet, by a factor of 1.5 to 3. The phospholipid fraction was the most highly labeled fraction in the liver, free fatty acids were the most labeled fraction in skin & fur, while triacyglycerols were the most labeled in the carcass and adipose tissue. In these tissues, more than 90% of the radioactivity was found in fatty acids with 2-double bonds in the tissue lipids. These data indicate that the majority of label found in guinea pig tissues 48 h after dosing was still associated with a fatty acid fraction with 2-double bonds, which suggests there was little metabolism of linoleic acid to more highly unsaturated fatty acids in this time frame. In this study, the labeling of guinea pig tissues with linoleic acid, 48 h after dosing, was quite different from the labeling with α-linolenic acid reported previously. The retention of the administered radioactivity from 14C-linoleic acid in the whole body lipids was 1.6 times higher in the group fed the low α-linolenic acid diet (diet contained a total of 1.8 g PUFA/100 g diet)compared with the group fed the high α-linolenic acid diet (diet contained 3.6 g PUFA/100 g diet). The lack of retention of 14C-labeled lipids in the whole body would be consistent with an increased rate of β-oxidation of the labeled fatty acid on the diet rich in PUFA, a result supported by other studies using direct measurement of labeled carbon dioxide.  相似文献   

14.
15.
随着开采的延续,渤海区块部分老油田产量逐渐降低,为了盘活老井、提高老油田采收率,采用套管开窗侧钻技术.通过对渤中25-1油田的基本情况和E3井的井身结构进行了调研,确定了侧钻点深度,介绍了此次开窗工具,重点讲述了开窗磨铣步骤,优化了开窗钻进参数和对钻井液性能要求,总结了施工过程中的成功经验.通过套管开窗侧钻技术的成功应用,为此类老井油田的高效开发提供了必要的借鉴.  相似文献   

16.
Groups of young rainbow trout were fed diets containing 0, 100 and 200 ppm methyl sterculate. Their tissue lipids were analyzed for cyclopropene content using the modified Halphen test. Halphenpositive compounds, calculated as sterculic acid, accumulated in all tissues analyzed and reached concentrations approximately equal to those of the dietary lipid. Gas liquid chromatography used in conjuction with mild hydrogenation of the cyclopropene ring revealed that these Halphen-positive compounds were predominantly, if not entirely, sterculic acid which was esterified in the triglycerides. To facilitate analysis of cyclopropenes in liver tissue, a method was developed whereby interfering pigments were removed prior to the Halphen test. Technical Paper No. 2944, Oregon Agricultural Experiment Station. This paper represents part of the thesis research conducted at Oregon State University in partial fulfillment for the degree of Doctor of Philosophy.  相似文献   

17.
18.
Nonanal-9-oic acid is incorporated principally into plasma phospholipids, whereas oleic acid is incorporated into red cells. This incorporation does not require the presence of adenosine 5′-triphosphate and Coenzyme A and is carried out in the absence of red cells. the incorporation of nonanal-9-oic acid in blood lipids takes place in the first 10 min of incubation.  相似文献   

19.
Pulmonary fibrosis is a consequence of the pathological accumulation of extracellular matrix (ECM), which finally leads to lung scarring. Although the pulmonary fibrogenesis is almost known, the last two years of the COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its post effects added new particularities which need to be explored. Many questions remain about how pulmonary fibrotic changes occur within the lungs of COVID-19 patients, and whether the changes will persist long term or are capable of resolving. This review brings together existing knowledge on both COVID-19 and pulmonary fibrosis, starting with the main key players in promoting pulmonary fibrosis, such as alveolar and endothelial cells, fibroblasts, lipofibroblasts, and macrophages. Further, we provide an overview of the main molecular mechanisms driving the fibrotic process in connection with Galactin-1, -3, -8, and -9, together with the currently approved and newly proposed clinical therapeutic solutions given for the treatment of fibrosis, based on their inhibition. The work underlines the particular pathways and processes that may be implicated in pulmonary fibrosis pathogenesis post-SARS-CoV-2 viral infection. The recent data suggest that galectin-1, -3, -8, and -9 could become valuable biomarkers for the diagnosis and prognosis of lung fibrosis post-COVID-19 and promising molecular targets for the development of new and original therapeutic tools to treat the disease.  相似文献   

20.
Adlof  R. O.  Emken  E. A. 《Lipids》1986,21(9):543-547
Thetrans 16∶1, 18∶1 and 18∶2 fatty acid composition of various human organ lipids was studied to determine if isomers accumulated in specific tissues. “Trans” isomers are defined as those fatty acids containing one or moretrans double bonds. Adipose, kidney, brain, heart and liver tissue lipids were analyzed. Gas chromatography with a 100-SP2560 capillary column was used to characterize the various positional and/or geometrical isomers. The distribution ofrans 16∶1 and 18∶1 isomers ranged from 0.3% in the brain to 4.0% in adipose tissue, whiletrans 18∶2 isomers ranged from 0.0% in the brain to 0.4% in adipose tissue. Notrans 18∶3 isomers were detected. Positional isomer ratios forcis 16∶1 (Δ9 vs Δ7) andcis 18∶1 (Δ11 vs Δ9) were also determined. Since these ratios are reproducible from one individual to the next, they might be useful for diagnosis of human metabolic disorders.  相似文献   

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