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1.
Oils extracted from three varieties of mature peanuts with chloroform/methanol (2:1, v/v) or petroleum ether and oils extracted with petroleum ether from one variety at eight distinct physiological maturity stages were fractionated by TLC. The three varieties of mature peanuts were quantitatively similar in relative percentages of lipid classes regardless of extraction solvent; however, oil composition of the one variety changed with maturity. Generally, triacyl-glycerol percentage increased and percentage of all other fractions decreased with maturity. The calculated weight per seed of most fractions increased from the lowest maturity stage tested up through stage 10 or 11, which corresponds closely with apparent physiological maturity of the seed.  相似文献   

2.
Epidemiological and laboratory animal model studies have provided evidence that the effect of dietary fat on colon tumorigenesis depends on the amount of fat and its composition. Because of the importance of the composition of dietary fat and of tissue membrane fatty acid composition in tumor promotion, experiments were designed to investigate the relative effects of high fat diets rich in ω3, ω6 and ω9 fatty acids and colon carcinogen on the phospholipid fatty acid composition of liver, colon, small intestine, erythrocytes and blood plasma. At 6 wk of age, groups of animals were fed diets containing 5% corn oil (LFCO), 23.5% corn oil (HFCO), 23.5% olive oil (HFOO), and 20.5% fish oil plus 3% corn oil (HFFO). Two weeks later all the animals except the vehicle-treated animals received azoxymethanes.c. once weekly for 2 wk at a dose rate of 15 mg/kg body weight. Animals were sacrificed 5 d later and liver, colon, small intestine and erythrocytes and blood plasma were analyzed for phospholipid fatty acids. The results indicate that the phospholipid fatty acid composition of liver, colon and small intestine of HFCO diet fed animals, were not significantly different from those fed the LFCO diet. The levels of palmitoleic acid and linoleic acid were increased in erythrocytes and blood plasma of the animals fed the HFCO diet compared to those fed the LFCO diet. Feeding the HFCO diet significantly increased the oleic acid content and decreased the linoleic acid and arachidonic acid levels in various organs when compared to the HFCO diet. Animals fed the HFFO diet showed a marked increase in eicosapentaenoic acid and docosahexaenoic acid and a decrease in linoleic acid and arachidonic acid levels as compared to those fed the HFCO diet. The results also indicate that carcinogen treatment had only a minimal effect on the phospholipid fatty acid composition.  相似文献   

3.
The effects of various chemical extraction procedures on the determination of lipid composition of rat and mouse brain have been investigated. Tissue extractions with formic acid/acetone or perchloric acid both resulted in significant losses of total phospholipids and cholesterol. Perchloric acid extraction also degraded, almost quantitatively, ethanolamine plasmalogens to lysophosphatidylethanolamine. Our findings have thus demonstrated that conventional procedures used for extraction of brain tissue for analysis of choline and acetylcholine content cannot also be used for concurrent/simultaneous extraction of phospholipids and cholesterol from the same tissue.  相似文献   

4.
In this study, we investigated the effect of various types of fats on heart lipid peroxidation status and on blood lipid parameters. Rats were fed either a low-fat diet (2.2% lard plus 2.2% corn oil), a corn oil diet (17%), a salmon oil diet (12.5%) supplemented with 4.5% corn oil, or a lard diet (15%) supplemented with 2% corn oil. All diets were supplemented with 1% cholesterol. Rats were fed for eight weeks. When compared with the low-fat diet, the salmon oil-diet intake resulted in a lower blood cholesterol, triglyceride and phospholipid concentrations (−50, −56 and −30%, respectively). Corn oil only tended to lower blood lipids; this decrease was significant for triglycerides only (−40%). The hypocholesterolemic effect of salmon oil diet is even more pronounced, if blood cholesterol values are compared with those of rats fed the lard diet. Heart lipid composition was not affected by dietary manipulations. Fatty acid composition of cardiac phosphatidylcholines and phosphatidylethanolamines, however, were altered by high-fat diets. In phosphatidylcholine, salmon oil induced a twelvefold decrease in the n−6/n−3 ratio and a 26% increase in the unsaturation index. For phosphatidylethanolamine, the n−6/n−3 ratio decreased 7.7-fold and the unsaturation index increased by 13%. A 50% decrease of the n−6/n−3 ratio was observed in animals fed the lard diet. Ultramicroscopic examination of ventricles revealed that those of the salmon oil group significantly accumulated lipofuscin-like or ceroid material, whereas this accumulation was barely detectable in hearts of the other groups. Seleniumdependent glutathione peroxidase activity tended to be the highest in hearts of rats fed the salmon oil diet; this increase is significant (+36% and +54% for total and specific activities, respectively), if values are compared with those of the rats fed the lard diet. Liver glutathione peroxidase and heart glutathione S-transferases activities remained unchanged. These results indicate that fish oil did not lower the selenium involved in glutathione peroxidase activity. This rules out that a deficiency in this enzyme was at the origin of heart lipofuscinosis. Also, it is concluded that the n−6/n−3 ratio of the diet is likely more determinant in the alteration of heart lipid peroxidation status than is the polyunsaturated/saturated ratio. Part of this work was presented at the International Congress: “Selenium in Medicine and Biology,” Avoriaz, France, March, 15–18, 1988.  相似文献   

5.
Total oil content and fatty acid composition of germ and endosperm oil were determined on grain from three inbred lines and one variety of corn (Zea mays L.) grown in four phytotron environments and one standard greenhouse environment during seed maturation. Pronounced differences occurred with reversals for relative percentages of oleic and linoleic acids of germ oil for one inbred line and for the variety. Comparative trends were generally less pronounced for two of the inbred lines. Differences among environments were less evident for palmitic, stearic, and linolenic acids of germ oil and for the fatty acids of the endosperm oil. Total oil was lowest for two inbred lines and the variety grown in the high temperature environment (30 C day/26 C night). The magnitude of temperature effects on oil content and oil composition varied among the four corn genotypes. Journal article 3961 of the North Carolina State University Agricultural Experiment Station. ARS, USDA.  相似文献   

6.
All commercial corn oil is obtained by the hexane extraction of corn germ. The chemical composition of commercial corn oil has been well characterized. This study was under-taken to quantitatively evaluate the lipid composition of corn oil obtained by the ethanol extraction of ground, whole corn kernels. When corn oil was obtained by extracting ground corn kernels (ground corn) with polar or nonpolar solvents, the resulting corn oil contained much higher levels of hydroxycinnamate steryl esters (≈0.3%) than those found in commercial hexane-extracted corn (germ) oil (≈0.02%). The levels of valuable tocopherols and tocotrienols were also significantly higher in kernel oil than in traditional corn germ oil. We previously reported that when corn oil was obtained by extracting corn kernels with polar solvents, the oil contained two polyamine conjugates, diferuloylputrescine and p-coumaroyl feruloylputrescine. In the current study, when ground corn was extracted with ethanol, the resulting corn oil contained about 0.5% diferuloylputrescine and about 0.2% p-coumaroyl feruloylputrescine. This is the first study to quantify these unique compounds in corn oil extracted by new techniques. This compositional information is important because this new oil is being considered for human food use.  相似文献   

7.
Feeding the ethyl ester of dihomo-γ-linolenic acid for 25 days to rabbits resulted in increased PGE1 (20to30-fold) and PGE2 (1.5-fold) output by a hormone responsive, in vitro, renal papilla preparation. The relative amount of PGE1 increased from <5% of PGE2 in controls to 25–35% of PGE2 in the papillae of 20∶3ω6-supplemented animals. During the study renomedullary triglycerides in the 20∶3ω6-supplemented animals increased 2.8-fold compared to animals fed an equal amount of a control fatty acid mixture, and in addition to a marked enrichment in 20∶3ω6, also contained increased proportions of 20∶4ω6 and longer chain polyenes. The increase in triglyceride content found in the renal medulla was not seen in the renal cortex or liver. There was no increase in renomedullary phospholipid content during the study, and phopholipids of treated animals contained increased proportions of 20∶3ω6 and 20∶4ω6, but not longer chain polyenes. The results indicate that enriching the prostaglandin precursor pool by feeding 20∶3ω6 can alter the type and amount of prostaglandin released by the renal papilla, at least in vitro. Also, the selective changes in amount and long chain polyene content of renomedullary triglycerides during the study suggest some special functions for this lipid class in prostaglandin precursor metabolism. *** DIRECT SUPPORT *** A00M6131 00010  相似文献   

8.
The phospholipid composition of platelets from dogs on various experimental diets was determined. Thyroidectomized foxhounds were fed a control diet or the control diet supplemented with (1) beef tallow, (2) beef tallow and cholesterol, or (3) beef tallow, cholesterol, and safflower oil for 23 weeks prior to isolation of platelets. Platelets from animals fed the control diet contained 36.7% phosphatidylcholine (PC), 22.8% phosphatidylethanolamine (PE), 18.4% sphingomyelin (Sph), 11.8% phosphatidylserine (PS), 6.3% phosphatidylinositol (PI), and 2.2% lysophosphatidylcholine. The PE was 77.6% in the plasmalogen form. No highly significant changes in the phospholipid class composition resulted from the experimental diets. Cholesterol supplementation of the diets, however, caused consistent alterations in the fatty acid compositions of the platelet phospholipids including increases in the percentages of 18∶1ω9 (oleic acid), 18∶2ω6 (linoleic acid), and 20∶3ω6 (homo-gamma linolenic acid) and a decrease in the percentage of 20∶4ω6 (arachidonic acid). Addition of safflower oil to the tallow-cholesterol diet partially reversed these effects. These cholesterol-induced alterations in fatty acid composition could be due to exchange with plasma lipids, de novo synthesis, or altered platelet metabolism. The mechanism remains to be determined. Der. Nelson’s current affiliation is the Lipid Metabolism Branch, Division of Heart and Vascular Diseases, National Heart, Lung, and Blood Institute.  相似文献   

9.
The fatty acid composition of corn oil can be altered to meet consumer demand for “healthful” fats. The first step in altering the oils is to survey existing corn breeding materials for fatty acid composition. The Latin American Maize Project (LAMP), an international program designed to evaluate the agronomic characteristics of maize accessions in Latin American and U.S. germplasm banks for future use, provides useful starting materials. LAMP was based on the cooperative efforts of 12 countries. In a two-stage evaluation, the project identified the highest-yielding open-pollinated top 20% of populations, then approximately the top 5% of those 20%. Twenty of the populations from four countries with temperate climates were randomly selected for fatty acid analysis. The populations were from United States, Chile, Argentina, and Uruguay. Fifty S1 lines from each population were randomly chosen for analysis for a total of 1,000 genotypes sampled. Statistical differences in fatty acid composition were computed among the 20 populations and among the four countries. The findings showed a wide range of fatty acid profiles present in unadapted, elite corn breeding materials with ranges for each fatty acid as follows: palmitic acid, 6.3–18.2%; stearic acid, 0.9–4.5%; oleic acid, 18.5–46.1%; linoleic acid, 36.6–66.8%; linolenic acid, 0.0–2.0%; and arachidic acid, 0.0–1.4%. Several populations were significantly different from the others. Some lines had unusual fatty acid compositions, including one with 8.3% total saturates and another with 20.2% total saturates. This study shows that existing corn breeding materials could be used to produce high- and low-saturate oils, but other methods would probably be required to produce a high-oleic corn oil.  相似文献   

10.
The effect of lupin (Lupinus termis) oil on the muscle lipids of carp (Cyprinus carpio) during chilling was studied. During chilling, total lipids decreased whereas triglycerides remained almost constant. Neither the behavior of total lipids nor that of triglycerides during chilling was affected by the composition of the dietary lipids. The proportions of ?free”? fatty acids increased and the proportions of phospholipids decreased during chilling. These changes were markedly affected by the composition of the diet.  相似文献   

11.
A new, simple method based on assay of cholesterol is presented for study of the time course and extent of air oxidation of cholesterol. Using such a method, the air oxidation of 0.5–3.5% solutions of corn oil sterols and cholesterol in films of either corn oil or corn oil fatty acids has been followed by the author for periods of up to 3 months at room temperature and 2 weeks at 60°C. in the dark. Under these conditions it was shown that a) solid cholesterol is relatively stable to air oxidation; b) in lipid films cholesterol is readily subject to oxidative attack which appears to be closely linked to the stability of the lipid film itself to autoxidation; c) more than 90% conversion of cholesterol to oxidation products has been observed in such systems; d) the principal corn oil sterols are oxidized at the same rate as cholesterol, and esterification of the corn oil sterols did not affect the rate at which they were oxidized; and e) the rate of concurrent oxidation of cholesterol in corn oil and corn oil fatty acid films in independent of the concentration of cholesterol at low concentrations, 0.5–3.5%. The disappearance rate is dependent on the stability of the lipid film itself as shown by peroxide value. Presented at the 34th Fall Meeting, American Oil Chemists' Society, October 17–19, 1960, New York, N.Y. This investigation was supported in part by a P.H.S. research grant (H-4623) from the National Heart Institute, Public Health Service.  相似文献   

12.
Randomization of partially hydrogenated corn oil containing approximately 45% oftrans octadecenoic acid only slightly, but not significantly, increased the lymphatic fatty acid absorption in rats. No effect of randomization was observed on cholesterol absorption. When rats were fed these fats at the 8.8% level (with 1.2% safflower oil) for three weeks, the concentrations of serum cholesterol, and serum and liver phospholipid were significantly higher in randomized fat than in control fat, which was composed of 9% high-oleic safflower oil and 1% palm oil. Liver cholesterol tended to be higher in randomized fat. In contrast, nonrandomized fat was not hyperlipidemic compared to control fat. Although the fatty acid composition of liver phospholipids suggested a possible interference oftrans fatty acid with the metabolism of linoleic acid to arachidonic acid, there was no effect of randomization. In the two hydrogenated fat groups,trans octadecenoic acid was incorporated and distributed similarly in adipose tissue triacylglycerol. These observations indicated that randomization of partially hydrogenated fat is not beneficial to various lipid parameters in rats.  相似文献   

13.
Male rats were administered 1.5 ml safflower oil by gastric intubation 0, 4, and 8 hr after a 16 hr fast. Plasma, liver, and adipose tissue were collected 16 hr after the last fatty meal. Rats fasted for 16 hr served as controls. Following fat feeding, the fatty acid composition of the very low density lipoprotein, triglyceride, and hepatic triglyceride were similar, as were the percentages of 18:2 in the very low density lipoprotein and hepatic cholesteryl esters. The phospholipids of liver and plasma lipoproteins were similar in the control groups, except that more 16:0 was present in the plasma lipoproteins. After fat feeding, the plasma lipoproein phospholipids were enriched with 18:2 more than were the hepatic phospholipids. Furthermore, the percentage of 18:2 in phospholipid was much less than in triglyceride or cholesteryl esters. Clearly, esterified lipids of liver and plasma lipoproteins (very low density lipoprotein, low density lipoprotein, and high density lipoprotein), and to a lesser extent, adipose tissue, were enriched with 18:2 derived from dietary triglyceride fatty acid even 16 hr after the terminal meal. A major proportion of the very low density lipoprotein isolated by ultracentrifugation in zonal rotors from plasma of fat fed animals had a faster rate-zonal mobility than did the very low density lipoprotein isolated from plasma of control animals. The very low density lipoprotein isolated from plasma of fat fed rats contained fewer moles of phospholipids, cholesterol, and cholesteryl esters, relative to triglyceride than did the very low density lipoprotein from plasma of animals not receiving safflower oil. The molar ratio triglyceride:phospholipid:cholesterol:cholesterol esters in the very low denity lipoprotein was 100:42.0:22.1:44.5 in the control group and 100:35.4:17.8:19.5 in the fat fed animals. It is postulated that an important biochemical mechanism by which dietary triglyceride fatty acids consumed by the animal over a long period of time alter plasma concentrations of triglyceride, phospholipids, and cholesterol esters is the directive influence of plasma free fatty acid, derived from dietary triglyceride, on the secretion of very low density lipoprotein lipids by the liver.  相似文献   

14.
When rats were fed a diet containing chow or fish oil for six weeks, the platelet phospholipid content and percent distribution were similar. In the fish oil fed animals there was a 54, 40, 41, and 24% reduction, respectively, in the levels of 20∶4(n−6) in the choline-, ethanolamine-, inositol-and serine-containing glycerophospholipids. Dietary fish oil increased the total (n−3) polyunsaturated fatty acid content in all lipids. This effect was most pronounced in the ethanolamine glycerophospholipids which now contained 26, 11, and 4 nmols of 20∶5(n−3), 22∶5(n−3), and 22∶6(n−3) in 109 cells. Ionophore A23187 stimulation of platelets from the chow fed rats resulted in the synthesis of 7, 64, and 3.5 nmols of 12-hydroxy-5,8,10-heptadecatrienoic acid, 12-hydroxy-5,8,10,14-eicosatetraenoic acid and 12-hydroxy-5,8,10,14,17-eicosapentaenoic acid, respectively, from 1×109 cells. The values from animals fed fish oil were 4, 18, and 27 nmol/109 platelets. It was not possible to detect any lipoxygenase products from 22∶5(n−3) or 22∶6(n−3), even though both acids are readily metabolized by lipoxygenase when added directly to platelets. These findings suggest that 22-carbon (n−3) fatty acids are not liberated when phospholipases are activated by calcium mobilization.  相似文献   

15.
Triglyceride composition of chrysalis oil,an insect lipid   总被引:1,自引:0,他引:1  
Chrysalis oil, an insect fat obtained from the spent silk worm pupae, Bombyx mori, is a by-product of sericultural industry and represents a potential source of 1750 tons of linolenic-rich oil per annum for India. Fatty acid and triglyceride compositions of chrysalis oil have been determined by the combination of the techniques of lower temperature segregation, lipolysis, thin layer and gas liquid chromatography. Percentage contents of the component acids are: C14:0, 0.6; C16:0, 19.3; C18:0 3.9; C18:1, 17.7; C18:2, 9.8, and C18:3, 48.7. Major component triglycerides are, LLnLn, 5.2%; PLnO, 6.4%;OLnLn, 9.6%; LnLnLn, 10.5% and PLnLn, 14.0% (P, palmitic; O, oleic; L, linoleic and Ln, linolenic acids. On low temperature crystallization, Chrysalis oil yielded two fractions amounting together to 40% of the total with composition quite similar to that of linseed oil.  相似文献   

16.
Although essential to host defense, neutrophils are also involved in numerous inflammatory disorders including rheumatoid arthritis. Dietary supplementation with relatively large amounts of fish oil [containing >2.6 g eicosapentaenoic acid (EPA) plus 1.4 g docosahexaenoic acid (DHA) per day] can attenuate neutrophil functions such as chemotaxis and superoxide radical production. In this study, the effects of more moderate supplementation with fish oil on neutrophil lipid composition and function were investigated. The rationale for using lower supplementary doses of fish oil was to avoid adverse gastrointestinal problems, which have been observed at high supplementary concentrations of fish oil. Healthy male volunteers aged <40 yr were randomly assigned to consume one of six dietary supplements daily for 12 wk (n=8 per treatment group). The dietary supplements included four different concentrations of fish oil (the most concentrated fish oil provided 0.58 g EPA plus 1.67 g DHA per day), linseed oil, and a placebo oil. The percentages of EPA and DHA increased (both P<0.05) in neutrophil phospholipids in a dose-dependent manner after 4 wk of supplementation with the three most concentrated fish oil supplements. No further increases in EPA or DHA levels were observed after 4 wk. The percentage of arachidonic acid in neutrophil phospholipids decreased (P<0.05) after 12 wk supplementation with the linseed oil supplement or the two most concentrated fish oil supplements. There were no significant changes in N-formyl-met-leu-phe-induced chemotaxis and superoxide radical production following the dietary supplementations. In conclusion, low-to-moderate amounts of dietary fish oil can be used to manipulate neutrophil fatty acid composition. However, this may not be accompanied by modulation of neutrophil functions such as chemotaxis and superoxide radical production.  相似文献   

17.
The fatty acid composition of corn oil can be altered to meet consumer demands for “healthful” fats (i.e., lower saturates and higher monounsaturates). To this end, a survey of 418 corn hybrids and 98 corn inbreds grown in Iowa was done to determine the fatty acid composition of readily-available, adapted, elite corn breeding materials. These materials are those used in commercial hybrid production. Eighty-seven hybrids grown in France (18 of which also were grown in lowa) were analyzed to determine environmental influence on fatty acid content. The parents of the hybrids and the inbreds were classified in one of four heterotic groups: Lancaster, Stiff Stalk, non-Lancaster/non-Stiff Stalk, and Other.t-Tests and correlation analyses were performed with statistical significance accepted at a level ofP≤0.05. The findings showed a wide range of fatty acid profiles present in adapted, elite corn breeding materials with ranges for each fatty acid as follows: palmitic acid, 6.7–16.5%; palmitoleic acid, 0.0–1.2%; stearic acid, 0.7–6.6%; oleic acid, 16.2–43.8%; linoleic acid, 39.5–69.5%; linolenic acid, 0.0–3.1%; and arachidic acid, 0.0–1.0%. Small amounts of myristic acid, margaric acid, and gadoleic acid also were found. Three lines had total saturates of 9.1% or less. Thirty-six of thet-tests involving hybrids showed significant differences among heterotic groups. There were small but significant correlations among protein, starch and oil content and the amounts of several fatty acids. Results from the corn grown in France vs. lowa demonstrated a large environmental effect that overwhelmed the genetic differences among lines. This study shows that for some attributes, a breeding program involving adapted corn breeding materials might produce the desired oil. Other types of oil (such as high-oleic) would have to be produced in a different manner, for example, by a breeding program with exotic breeding materials.  相似文献   

18.
Cyclopropenoid fatty acids (CPE) isolated fromSterculia foetida oil by urea clathration and reverse phase high performance liquid chromatography (HPLC) were introduced into fungal cultures. Stearate levels in phospholipids and triacylglycerols fromUstilago maydis sporidia rose considerably in response to 30 μM CPE. In addition, CPE themselves were incorporated into glycerolipid fractions. Sterol composition was unaffected. Changes in lipid composition were accompanied by inhibition of dry weight accumulation and sporidial number. Treated sporidia showed irregular wall deposition and a branched morphology. Oleate alleviated CPE effects on growth and morphology. Hyphal extension byRhizoctonia solani was inhibited somewhat by 30 μM sterculate, whileFusarium oxysporum showed no appreciable response. Although CPE appeared to inhibit fatty acid desaturation byF. oxysporum, gross increases in the proportion of stearate were limited to the triacylglycerol fraction during 30 μM treatments. The possibility that the CPE synthesized by plants serve as antifungal agents is discussed.  相似文献   

19.
The general public has shown increasing interest in consuming oils that are beneficial to health. Thus, oil from corn (Zea mays L.), along with most major edible oils, has been the target of genetic alterations to improve the fatty acid composition. The fatty acid profile goals vary, depending upon the intended use for the oil. We have targeted the development of corn oil with 1) low total saturated fatty acids, 2) high total saturated fatty acids, and 3) mid‐oleic acid, in each case via two different sources: exotic germplasm identified through an international program to broaden the corn germplasm base and introgression of a wild, grassy relative of corn, Tripsacum (Tripsacum dactaloides L). We have been successful at identifying corn lines with each of the noted traits.  相似文献   

20.
Potato chips were fried in six canola (low-erucic acid rape-seed) oils under pilot-plant process settings that represented commercial conditions. Oil samples included an unmodified canola oil and oils with fatty acid compositions modified by mutation breeding or hydrogenation. Chips were fried for a 2-d, 18-h cycle for each oil. Chips and oil were sampled periodically for sensory, gas-chromatographic volatiles and chemical analyses. Unmodified canola oil produced chips with lower flavor stability and oxidative stability than the other oils. The hydrogenated oil imparted a typical hydrogenation flavor to the chips that slightly affected overall quality. the modified canola oil (IMC 129) with the highest oleic acid level (78%) had the lowest content of total polar compounds and the lowest total volatile compounds at most of the storage times; however, the sensory quality of the potato chip was only fair. The potato chip with the best flavor stability was fried in a modified/blended oil (IMC 01-4.5/129) with 68% oleic acid, 20% linoleic acid and 3% linolenic acid.  相似文献   

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