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1.
Glycerides (65%), ascaroside esters (33%), waxes (1.5%) and sterols (0.26%) accounted for essentially all the neutral lipids inA. lumbricoides ovaries. Nineteen per cent by weight of the triglycerides contained only long chain fatty acids. Nearly all the remaining triglycerides contained 1 mol volatile acid. Mono- and diglycerides, free fatty acids and triglycerides containing 2 mol volatile acids were present in very small amounts. Mole percentages of glyceride volatile acids were α-methylavaleric (70), α-methylbutyric (23),n-valeric (ca. 7), and traces of acetic, propionic, isobutyric andn-butyric. Mole percentages of the alcoholic component of the waxes were 96% 1-octadecanol, and 4% of its 16, 17 and 19 carbon homologs. The acid components were α-methylbutyric (75 mol%), acetic (16 mol%), propionic andn-valeric (each 4 mol%), and traces ofn-butyric and α-methylvaleric. Sterols (42 wt% cholesterol, 30% cholestanol, 9.5% campestanol, 8.2% stigmastanol, 6.6% β-sitosterol, and 3.8% campesterol) were essentially the same as those found in the whole worm, except that no esterified sterols were present.  相似文献   

2.
The effect of long-chain n−3 fatty acids on hepatic key enzymes of cholesterol metabolism and triglyceride biosynthesis was investigated in two rat models. In the first model, rats were intravenously infused for two weeks with a fat emulsion containing 20% of triglycerides in which either n−6 or n−3 fatty acids predominated. The treatment with n−3 fatty acids led to a reduction primarily of serum cholesterol (45%), but also of serum triglycerides (18%). HMG-CoA reductase activity and cholesterol 7α-hydroxylase activity were reduced by 45% and 36%, respectively. There were no significant effects on diacylglycerol acyltransferase (DGAT) or phosphatidate phosphohydrolase (PAP) activities. In the second model, rats were fed a diet enriched with sucrose, coconut oil and either sunflower oil (n−6 fatty acids) or fish oil (long-chain n−3 fatty acid ethyl esters). The treatment with n−3 fatty acids decreased serum triglycerides (41%) and, to a lesser extent, serum cholesterol (17%). Neither glycerol 3-phosphate acyltransferase (GPAT) or DGAT were affected by n−3 fatty acids. In contrast, PAP activity was reduced by 26%. HMG-CoA reductase was not significantly affected, whereas cholesterol 7α-hydroxylase activity was reduced by 36%. The results indicate that part of the TG-lowering effect of long-chain n−3 fatty acids may be mediated by inhibition of the soluble phosphatidate phosphohydrolase. The effect on serum cholesterol may be partly due to inhibition of HMG-CoA reductase.  相似文献   

3.
Interesterified plastic fat products based on a) sal fat and groundnut oil (30: 70, w/w;P/S,0.8) (sal-GNO);b) vanaspati, partially hydrogenated vegetable oil and groundnut oil (40:60; P/S, 1.0; isolated trans fatty acid content 17%) (vanaspati-GNO);c) cottonseed oil (P/S, 1.5) (CSO) and d) sal fat and safflower oil (50:50, P/S, 1.3) (sal-saff) were prepared using dry sodium methoxide as the catalyst. The products had slip points of 33?34°C. These products, their original blends, safflower oil (P/S, 8.5) and a blend of vanaspati and safflower oil (50 : 50, P/S, 2.8 and isolated trans fatty acid content 22%) (vanaspati-saff) were tested for hypolipidaemic effect (serum total cholesterol, total lipids, triglycerides and phospholipids) in cholesterol-bile salt stressed rats. All the test fats having linoleic acid content varying from 21.9-76.6% and P/S ratio from 0.8 to 8.5 and fed at 10% level providing 23% calorie were found to be superior to vanaspati (P/S, 0.16, 3% linoleic, 43% isolated trans fatty acids). P/S ratio of 1.5 and linoleic content of 30% in fat were found to be optimum for maximum hypolipidaemic effect at above dietary regimen. Fat and cholesterol contents of liver of animals, fed test lipids were significantly lower than that of animals fed vanaspati. when linoleic acid content of the product was comparatively low (e.g. sal-GNO, 25%), the process of rearrangement reduced the cholesterol content of liver. With high linoleic acid content (CSO, 48.2% or sal-saff, 40.4%) interesterification was without any effect. Hypolipidaemic effect of interesterified products was similar to that observed with original materials. Thus, the above quality of a fat having characteristics within the above ranges does not depend upon the distribution of acyl groups in glyceride molecules. Isolated trans fatty acids behaved more or less like a saturated fatty acid in elevating serum lipids. Vanaspati was found to be highly hyperlipidaemic.  相似文献   

4.
The Skin-Surface Lipids in Psoriasis vulgaris (Ps) - Cholesterol Esters, Wax Esters, Triglycerides and Fatty Alcohols The composition of waxes and cholesterol esters, triglycerides and alcohols of hair lipids from subjects with psoriasis vulgaris and control group was determined by gas liquid chromatography. The amount of palmitoleic acid was lower in the lipid group of the waxes and cholesterol esters in psoriasis vulgaris. Triglycerides show two different changes in the fatty acid pattern by psoriasis: 1) the composition of shorter chain fatty acids was distinct lower but 2) patients with a heavy psoriasis show an increase of the shorter chain fatty acids especially lauric acid and a decrease of the longer chain fatty acids. The analysis of the alcohols indicates that psoriatic patients possess a higher content of alcohols with 12,13 and 14 carbonatoms than normal subjects.  相似文献   

5.
In view of the high potential of ricebran oil in India, lecithins recovered from crude and dewaxed Indian ricebran oil were analyzed and different classes characterized with the objective of effectively utilizing this valuable by- product. Lipid classes and individual phospholipid components were identified and estimated. Dewaxing was found to have a considerable effect on composition of the derived lecithin. The lecithin obtained from crude or dewaxed Indian ricebran oil consisted mainly of phosphatidylcholine, phosphatidylethanolamine, phosphatidylnositol and triglycerides, along with carbohydrates, free fatty acid, sterols and waxes (in case of crude oil). The major fatty acids of individual phospholipids were found to be palmitic, oleic and linoleic. Analytical characteristics of ricebran lecithin were shown to be comparable to local soybean lecithin. It can be expected that the gummy materials in the oil, presently lost with the soapstock during refining, could find important applications.  相似文献   

6.
Inge Bojesen 《Lipids》1974,9(11):835-843
The lipid droplets of renal papillae homogenates from four different species were obtained by ultracentrifugation. Ca. 80–98% of the lipids (triglycerides, phospholipids, free fatty acids, and cholesterol esters) consist of triglycerides. The triglycerides were fractionated by argentation thin layer chromatography and each fraction characterized by gas liquid chromatography. No fraction contained any unique triglyceride. The fatty acid composition of the total triglycerides, as analyzed by gas liquid chromatography and ozonolysis, differed markedly from the fatty acid composition of the corresponding plasma triglycerides. The papillary triglycerides were characterized by higher concentrations of stearic acid, arachidic acid, and polyunsaturated acids with 20 or more carbon atoms. Particularly interesting was the presence in the lipid droplets of docosa-7,10,13,16-tetraenoic acid. This acid has been shown to be a major component in the cholesterol ester fraction of rat and canine adrenal lipids. In the papillary triglycerides, this acid accounted for 7%, 15%, and more than 20% of the total fatty acids in the dog, rat, and rabbit, respectively. The pig differs from these three species in having only ca. 1% of this acid. These observations suggest that the interstitial cells produce these triglycerides. This production could occur either by a transacylation from phospholipids and cholesterol esters and by a de novo synthesis from locally produced fatty acids. The possibility that the triglyceride production may be involved in a control of the prostaglandin production of the renal medulla is discussed.  相似文献   

7.
Three separate experiments show that cholesterol administered to rabbits in the absence of added fat is more atherogenic than cholesterol fed together with corn oil. When cholesterol is dissolved in the corn oil (by heating) prior to mixing with the diet, it is more atherogenic than when it is suspended in the oil. In every case the lowest serum and liver cholesterol levels were observed in the group not receiving corn oil. Gas chromatography of the fatty acids of the serum cholesterol esters of pooled sera suggest that there are smaller amounts of unsaturated C18 fatty acids in the cholesterol-no fat group. Deficiency in these unsaturated acids may be the cause of the high atherogenicity of the cholesterol-no fat diet. There is also a lower proportion of unsaturated fatty acids in the triglycerides of this group. Heating of corn oil 10 min, at 160–200(°C.) causes an increase of titratable fatty acid in the oil (0.005 m-equiv./g. to 0.088 m-equiv./g. or 0.14% FFA to 2.5% FFA). The relatively large amounts of free unsaturated fatty acids in the heated oil may be the cause of the greater atherogenicity of the solution, as compared to the suspension, of cholesterol in corn oil. Presented at the 33rd Fall Meeting, American Oil Chemists’ So ciety, Los Angeles, Calif., September 28–30, 1959. This work was supported by grants from the National Institutes of Health (H-3299 and A-2131), The Nutrition Foundation Inc., and The John A. Hart-ford Foundation Inc.  相似文献   

8.
Walnut (Juglans regia) kernel and its oil were found to reduce serum cholesterol, triglycerides, phospholipids and total lipids in cholesterol bilesalt stressed hypercholesterolaemic rats. Kernel was as effective as its oil (unrefined or refined); thus the efficacy of kernel was due to its oil content having about 70 % polyunsaturated fatty acids. Both unrefined and refined oils having different contents of unsaponifiable matter and sterols behaved in a similar way indicating that unsaponifiable matter and sterol contents of oil were not responsible for their efficacy. There was no difference in faecal cholesterol in animals given vanaspati, walnut kernel or its oil; thus hypolipidaemic effect observed with walnut kernel or its oil could not be attributed to any differences in faecal cholesterol. Serum SGO-T activity of animals of groups given vanaspati, walnut kernel, walnut oil and safflower oil was similar and normal. The blend of vanaspati and walnut oil (1:1) was as effective as walnut kernel and its oil. The study brings to light special value of walnut kernel as a food material in reducing serum lipid constituents.  相似文献   

9.
We have analysed the fatty acid composition of 45 different vegetable oil margarines collected in different European countries during 2004–2005 and estimated their effect on blood cholesterol. Trans fatty acids in amounts 4–6% of total fatty acids were detected in 3 margarines, otherwise only trace amounts (<1%) were detected. Of the 45 margarines 10 were found to have a neutral or a slight cholesterol decreasing effect. The others were found to be cholesterol increasing with substantial variation in effect, although less hypercholesterolemic than butter. Palmitic acid contributed most to the estimated cholesterol increasing effect and the correlation coefficient between the amount of palmitic acid and the change in cholesterol was 0.82. Myristic acid also contributed to a certain extent while lauric acid contributed little. The content of stearic acid was >10% in 6 samples but otherwise present in low amounts. It thus appears that palmitic acid, presumably from palm oil, to a large extent has replaced trans fatty acids in margarines. A better alternative might be to use fat blends with higher contents of the cholesterol neutral stearic acid, such as fully hydrogenated and interesterified fat.  相似文献   

10.
Triglyceride composition and fatty acid profiles of pomegranate seed oil were evaluated by newly developed methods in reverse‐phase‐high performance liquid chromatography (RP‐HPLC) and gas chromatography (GC), respectively. Different compositions of the mobile phase (acetone and acetonitrile) and flow rates for the HPLC system were used to obtain better separation for accurate quantitative analysis. Triglycerides with conjugated fatty acids (CLnAs) were eluted in order of the polarity of their geometrical isomers (c, t, c < t, t, c < t, t, t). The dominant triglyceride was found to be PuPuPu (32.99 %) in pomegranate seed oil, followed by PuPuCa and PuCaCa containing punicic acid and catalpic acid with total triglyceridelevels of 27.72 and 10.11 %, respectively. For fatty acid composition analysis, triglyceride fractions were derivatized into their respective methylesters which were injected into gas chromatography‐mass spectrometry (GC‐MS) to identify and gas chromatography‐flame ionization detector (GC‐FID) to quantify the conjugated fatty acids of each fraction of triglycerides. Punicic acid was found to be dominant (76.57 %) followed by catalpic acid (6.47 %) and β‐eleotearic acid (1.45 %). Pomegranate seed contained greater amounts of conjugated linolenic acids. These results showed that the present study provides more information about the composition of the triglyceride and fatty acid profiles of pomegranate seed oil compared to the reported studies. Therefore, the developed methods in this study can be used for the identification of the triglyceride and fatty acid composition for pomegranate seed oils and some such specials edible oils including CLnA isomers.  相似文献   

11.
The saturated sn-2-triglycerides (the fatty acid esterified at the 2-position is known) of palm-kernel oil, representing 78%, was isolated by argentation thin-layer chromatography. The nine groups of this fraction (triglycerides with the same total acyl carbon atoms) were fractionated by gas-liquid chromatography and their component fatty acids determined. From the fatty acid composition of each group it was possible to determine mathematically the component triglyceride types of the group (the 3 fatty acids are known, but their positional distribution is not). The proportion of 46 types were calculated in this way. The major fractionate groups (6 out of 9) were hydrolyzed by pancreatic lipase. From the component 2-mono-glycerides it was possible to determine the proportion of 44 sn-2-triglycerides which account for 75% of the oil triglycerides. Trilaurin (21%) is the major component, followed by sn-2-lauro-1,3-lauromyristin (12%). These two triglycerides together form one third of the glyceride content of the oil. Sn-2-lauro-1,3-caprylolaurin (7%), 5 sn-2-triglycerides (2 to 5%), 9 (1 to 2%) were also found, and 27 triglycerides present at less than 1%. The calculated 1,3-random-2-random distribution of fatty acids on glycerol molecules exhibited great differences from the experimentally determined distribution. Consequently, calculations of this kind cannot replace a complete analytical analysis of palm-kernel oil such as the one reported in this work.  相似文献   

12.
The amounts of the different carotenoids (lutein, lutein monoesters and diesters) in soybean and rapeseed oil were determined through a combination of column chromatography and UV spectrometry. The lutein diesters in the oils have been isolated by a combination of column and thin layer chromatography. Identification and determination of the amount of the various fatty acids of the lutein diesters have been carried out by means of gas chromatography after transesterification of the fatty acids to their methyl esters. Comparison of the fatty acids of the lutein diesters with those of the triglycerides of the oils revealed a striking difference. First, the fatty acids of the lutein diesters have shorter chains than the triglycerides acids. Secondly, the lutein fatty acids are more saturated than the fatty acids of the triglycerides of the corresponding oils. However the amount of linoleic acid in the case of the fatty acids of the lutein diesters in rapeseed oil is greater than that in the fatty acids of the triglycerides in rapeseed oil. Deceased, October 26, 1971.  相似文献   

13.
Randall Wood  John Falch 《Lipids》1974,9(12):979-986
Minimal deviation hepatoma 7288C cells were cultured in a modified Swim's medium supplemented with decreasing levels of serum, lipid-free serum, lipid-free serum plus fatty acids, and other additives. Cellular and media neutral lipid classes were quantitated, the fatty acids of triglycerides and sterol esters analyzed, and the carbon number distribution of triglycerides determined. Cellular triglyceride biosynthesis virtually was inhibited when the medium was supplemented with bovine serum alone. This inhibition was not observed when the medium was supplemented with fetal calf serum alone or mixtures of fetal calf serum and bovine serum. Cells cultivated on medium supplemented with lipid-free serum plus palmitic or linoleic acids had much lower levels of free and esterified cholesterol. The fatty acid composition of cellular triglycerides and cholesterol esters differed dramatically from the corresponding media lipid classes. Except when linoleic acid was added to the medium, changes in the media serum and lipid levels had only marginal effects upon the fatty acid composition of cellular triglycerides and cholesterol esters. These data, in conjunction with earlier data that showed the media neutral lipid levels did not decrease during cell growth, indicate that these hepatoma cells utilize little or no serum triglycerides and cholesterol esters. Linoleic acid added to the medium dramatically reduced the level of 18∶1 acids in cellular triglycerides and cholesterol esters. Palmitic acid added to the medium did not change the fatty acid compositions significantly. Comparison of experimentally determined and calculated triglyceride carbon number percentages indicated a random distribution of fatty acids in this glyceride. The fatty acid composition of cellular triglycerides was similar to the composition of the cholesterol esters. The lack of characteristic and distinguishable compositions of these two classes that occur in most normal tissues suggests a loss of specificity in the lipid metabolism of this neoplasm at the class level.  相似文献   

14.
Beef tallow and cottonseed oil were mixed with a pure butterfat in the ratios of 2%, 4% and 6% to obtain admixtures of beef tallow with butterfat and cottonseed oil with butterfat. The hydrolysis of individual triglycerides was carried out using the lipase to obtain 2-monoglycerides. The results indicated that butterfat had a higher percentage of C14:0 and C16:0 acids than found in the triglycerides and 2-monoglycerides of beef tallow and cottonseed oil. Beef tallow contained a higher proportion of C18:0 and C18:1 acids than butterfat and cottonseed oil triglycerides or 2-monoglycerides. Cottonseed oil had a higher percentage of C18:2 acid located in triglyceride or 2-monoglyceride than found in butterfat or beef tallow triglycerides and 2-monoglycerides. The analysis of the samples of butterfat containing 2%, 4% and 6% beef tallow revealed that the addition of beef tallow to butterfat affected the fatty acid composition of butterfat triglycerides and 2-monoglycerides with C18:0 and C18:1 acids; the effect was increased with increasing percentages of beef tallow. The addition of cottonseed oil to butterfat in the ratios of 2%, 4% and 6% affected the fatty acid composition of butterfat triglycerides and 2-monoglycerides. It was found that both C18:1 and C18:2 increased as the added cottonseed oil percentages increased.  相似文献   

15.
Jürgen Jacob 《Lipids》1976,11(11):816-818
The uropygial gland of the white stork secrets mono- and diester waxes as well as triglycerides, all of which contain unbranched medium chain fatty acids. n-Decanol and n-dodecanol have been the only alcohols detected in both types of waxes. The diester waxes contain 2-hydroxy fatty acids.  相似文献   

16.
Rats red ad lib. for 12 weeks either a fat-free diet, a diet containing 15% cottonseed oil, or a diet containing 15% cuttlefish liver oil, with or without exogenous (1%) cholesterol, were studied to evaluate and compare the effect of polyunsaturated fatty acids of cuttlefish liver oil and cottonseed oil on cholesterol metabolism. The results indicate that the longer chain polyunsaturated fatty acids contained in the fish oil cannot substitute for the essential fatty acid, linoleic, either as far as effect on various aspects of cholesterol metabolism are concerned or in the ability to form arachidonic acid. The observed interference of cuttlefish liver oil with the absorption of exogenous cholesterol may be caused by the presence in this oil of the highly unsaturated long chain fatty acids.  相似文献   

17.
The soldier beetleChauliognathus lugubris is shown to contain triglycerides and glyceride ethers of 8-dihydromatricaria acid, and waxes of the C12 homolog, of this acid, as well as the previously reported free acid. The triglycerides contain one, two, or three dihydromatricariate moieties, with any remaining positions esterified with normal fatty acids. The glyceride ethers were monostearyl ethers of glycerol esterified with dihydromatricaria acid and oleic or linoleic acid. The waxes, which also include a dihydromatricaria chromophore in the alcohol moiety, occur only in the females and are present in paired accessory glands in the abdomen. The ethers are restricted to females and appear to be associated with developing eggs. The triglycerides are much more abundant in females than males. Triglycerides, glyceride ethers, and waxes represent about 95% of the dihydromatricariate moiety (average, ca. 590 g) in females with free acid the remainder; in males free acid is present to over 50% (ca. 22 g) and the remainder is triglyceride (ca. 15 g). Larvae contain mainly tridihydromatricariate-substituted triglyceride and a smaller quantity of the free acid.  相似文献   

18.
The major fatty acids of peanut oil acylglycerols are palmitic (C16:0), oleic (C18:1), and linoleic (C18:2) acids, and only a trace amount of linolenic fatty acid (C18:3) is present. Thus they have a very convenient oxidative stability and have been considered premium cooking and frying oils. This paper provides information about compositional data of peanut oil taking into account major (triacylglycerols and their fatty acids) and minor (free fatty acids, diacylglycerols, phospholipids, sterols, tocopherols, tocotrienols, triterpenic and aliphatic alcohols, waxes, pigments, phenolic compounds, volatiles, and metals) compounds. Moreover, the influence of genotype, seed maturity, climatic conditions, and growth location on peanut oil chemical composition is considered in the present report. In addition, peanut oils from wild species found in South America as well as from peanut lines developed through conventional breeding are also compared.  相似文献   

19.
The serum fatty acid profiles of patients receiving either intravenous medium or long chain triglycerides were studied. Seventeen hospitalized patients, dependent on total parenteral nutrition, were randomly enrolled into a prospective study. The total parenteral nutrition (TPN) delivered amino acids and glucose and either a 75% medium chain triglyceride and 25% long chain triglyceride (MCT group) physical mixture or all long chain triglyceride (LCT group), as the respective fat sources. The amino acids and glucose were given continously, and the lipid was given for 10 hours each day over five days. Fatty acid profiles on serum triglycerides and free fatty acids were done in the morning before any lipid was given and also later in the afternoon, near the end of the lipid administration, on days 1, 3 and 5. Medium chain fatty acids rose quickly in the triglyceride fraction in patients given MCT. Rapid MCT hydrolysis occurred as evidenced by the appearance of medium chain fatty acids in the free fatty acid fraction in the afternoon sampling. Clearance of the hydrolyzed medium chain free fatty acids (MCFFA) occurred so that little, if any, were present in the morning sampling one day later. Long chain fatty acids, as either triglycerides or free fatty acids, showed expected increases during the daily infusion, but not of such relative magnitude as the medium chain fatty acids. Medium chain fatty acid incorporation into the phospholipid or cholesterol ester fractions by the end of the five-day feeding period was present but minimal. As opposed to conventional long chain triglycerides, intravenously administered medium chain triglycerides are hydrolyzed and cleared rapidly and do not accumulate in other lipid fractions, and are therefore a more readily available lipid fuel.  相似文献   

20.
The objective of this study was to investigate the use of lipases as catalysts for separating eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish oil by kinetic resolution. Transesterification of various fish oil triglycerides with a stoichiometric amount of ethanol by immobilized Rhizomucor miehei lipase under anhydrous solvent-free conditions resulted in a good separation. When free fatty acids from the various fish oils were directly esterified with ethanol under similar conditions, greatly improved results were obtained. By this modification, complications related to regioselectivity of the lipase and nonhomogeneous distribution of EPA and DHA into the various positions of the triglycerides were avoided. As an example, when tuna oil comprising 6% EPA and 23% DHA was transesterified with ethanol, 65% conversion into ethyl esters was obtained after 24 h. The residual glyceride mixture contained 49% DHA and 6% EPA (8:1), with 90% DHA recovery into the glyceride mixture and 60% EPA recovery into the ethyl ester product. When the corresponding tuna oil free fatty acids were directly esterified with ethanol, 68% conversion was obtained after only 8h. The residual free fatty acids comprised 74% DHA and only 3% EPA (25:1). The recovery of both DHA into the residual free fatty acid fraction and EPA into the ethyl ester product remained very high, 83 and 87%, respectively.  相似文献   

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