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1.
Lipid depletion of berseem seed treated with 100 mg/1 gibberellic acid or maleic hydrazide was studied during germination. During the first 3 days after germination there was little lipid consumption but thereafter the depletion of lipid was rapid. Gibberellic acid was found to enhance the lipid utilization of total lipids and triglyceride components during germination. On the other hand, maleic hydrazide reduced the utilization of triglycerides of the germinating seed. The rate of utilization was rapid for unsaturated fatty acids and slower for saturated ones in treated seeds as compared to untreated seeds.  相似文献   

2.
Seven day old seedlings of Echinochloa crus-galli var. oryzicola (Vasing) had a higher total lipid content when germinated under N2 than in air, although ungerminated seeds contained more lipid than either seedling. The triacylglycerol pool was not depleted under anaerobiosis as it was in air and only air-grown seedlings showed a net increase in free fatty acids and polar lipids. Concentrations of most of the individual acids of the total fatty acid profile declined during germination in air and in the free acid and polar lipid fractions of these seedlings the relative proportion of polyunsaturated fatty acids increased. Compared to air-grown seedlings, ungerminated seeds and N2-grown seedlings had a similar qualitative and quantitative lipid composition. Our results show that mobilization of storage lipids was apparently severely inhibited under anoxia. The importance of lipid metabolism to the germination and growth of Echinochloa during anoxia is discussed in terms of maintaining membrane integrity and serving (indirectly) to reoxidize pyridine nucleotides.  相似文献   

3.
Anorexia nervosa is a model of simple starvation accompanied by secondary hyperlipoproteinemia. The pattern of plasma fatty acids influences the levels of plasma lipids and lipoproteins. The concentration of plasma lathosterol is a surrogate marker of cholesterol synthesis de novo, concentrations of campesterol and beta-sitosterol reflect resorption of exogenous cholesterol. The aim of the study was to evaluate fatty acids in plasma lipid classes and their relationship to plasma lipids, lipoproteins, cholesterol precursors and plant sterols. We examined 16 women with anorexia nervosa and 25 healthy ones. Patients with anorexia nervosa revealed increased concentrations of total cholesterol, triglycerides, HDL-cholesterol, campesterol and beta-sitosterol. Moreover, a decreased content of n-6 polyunsaturated fatty acids was found in all lipid classes. These changes were compensated by an increased content of monounsaturated fatty acids in cholesteryl esters, saturated fatty acids in triglycerides and both monounsaturated and saturated fatty acids in phosphatidylcholine. The most consistent finding in the fatty acid pattern concerned a decreased content of linoleic acid and a raised content of palmitoleic acid in all lipid classes. The changes of plasma lipids and lipoproteins in anorexia nervosa are the result of complex mechanisms including decreased catabolism of triglyceride-rich lipoproteins, normal rate of cholesterol synthesis and increased resorption of exogenous cholesterol.  相似文献   

4.
Three compounds capsaicin, curcumin and ferulic acid showing hypolipidemic activity have been tested in adult Wistar rats fed high fat diets. Capsaicin (0.20 mg%) fed to female rats along with a 30% saturated fat diet lowered the rate of weight gain, liver and serum triglycerides. In male rats it lowered only the liver and serum total and very low density and low density lipoprotein triglycerides whether fed continuously for 13 or 8 weeks after interchanging the control and test diets from the 5th week onwards. Capsaicin fed to female rats in 30% mixed fat diet increased the rate of weight gain, lowered liver and serum triglycerides, lowered adipose tissue lipoprotein lipase, elevated the hormone sensitive lipase and serum free fatty acids. Capsaicin in 30% saturated fat diet lowered both the enzyme activities to a much lesser extent. Curcumin and ferulic acid (both at 25 mg%) in 30% saturated fat diet tended to lower the rate of weight gain, liver total lipids and serum triglycerides. It is of significance that a common dietary compound ‘capsaicin’ in the range of human intake triggers lipid lowering action in rats fed high fat diets. This paper was presented at the 55th Annual Meeting of the Society of Biological Chemists (India) held at Trivandrum during December 15–17th, 1986.  相似文献   

5.
The objective of the present study was to evaluate the lipid composition of cultured and non-cultured pig embryos during cleavage using histochemical methods. The authors studied pig zygotes as well as 2-to 4-cell embryos, morulae, and blastocysts that were either non-cultured or cultured in NCSU-23 medium. To detect different types of lipids, the authors used the Churukian method with Oil red O, the Sudan black B method, the Cain method with Nile blue sulfate, and the modified osmium tetroxide-ethanol treatment. In the zygotic lipid droplets, diverse classes of unsaturated and saturated lipids were found, with particularly high levels of unsaturated hydrophobic lipids, mainly triglycerides and other esters, free fatty acids, and phospholipids. In the zygotic cytoplasm, the authors observed high levels of fatty acids and phospholipids. The total lipid content remained constant up to the morula stage, decreasing later at the blastocyst stage, but the overall amount of unsaturated lipids declined earlier, at the 2-to 4-cell stage. The amount of free fatty acids and phospholipids decreased during cleavage in both non-cultured and cultured porcine embryos. The main differences between the non-cultured and cultured embryos were the more pronounced reduction in the amount of unsaturated hydrophobic lipids in droplets and the cytoplasmic free fatty acids observed in the cultured morula and the lower content of phospholipids in the cytoplasm of the cultured 2-to 4-cell embryos relative to the non-cultured embryos. The decrease in the unsaturated lipid, free fatty acid, and phospholipid content during in vivo development and the differences in the amount of these types of lipids between developmentally matched cultured and non-cultured pig embryos correlate well with modifications of lipid and carbohydrate metabolism.  相似文献   

6.
Neutral lipids, particularly triglycerides, accounted for the major decrease in the total lipid content in Paramecium cells that occurs with culture age. Sterols, triglycerides, and steryl esters were the major classes of neutral lipids in cells and isolated cilia. Free as well as high concentrations of esterified sterols were detected in purified ciliary membrane preparations. Stigmasterol and 7-dehydrostigmasterol were the major components of both free and esterified sterols of cells and cilia; however, when cholesterol was present in the growth medium, it was desaturated to 7-dehydrocholesterol and incorporated into cellular and ciliary lipids. Free fatty acids from cells and triglycerides from cells and cilia were low in polyunsaturated fatty acids and reflected the composition of fatty acids in the culture medium. An exception was the reduced concentration of stearate in triglycerides from whole cells. Greater than 50% of triglyceride fatty acids from cilia were saturated. The fatty acid compositions of cellular triglycerides and ciliary steryl esters did not change with culture age, but those of cellular steryl esters and ciliary triglycerides did change. In comparison with phospholipids, these neutral lipid fatty acid compositional changes were smaller. The sensitivity of these stigmasterol-containing cells to polyene antibiotics indicated that they were killed by nystatin > filipin > amphotericin B. The unexpected finding of high concentrations of steryl esters in ciliary membrane preparations is discussed.  相似文献   

7.
目的:研究柏子仁与侧柏叶的脂肪酸组成.方法:用GC-MS方法对侧柏叶子与种子油进行定性鉴定和定量分析.结果:鉴定了柏子仁油中的8种脂肪酸,占脂溶性成分的93.56%;侧柏叶子油中12种脂肪酸,占脂溶性成分的93.39%.柏子仁饱和脂肪酸主要是十六烷酸(8.11%)、硬脂酸(6.08%);不饱和脂肪酸主要为亚油酸(24.59%)、亚麻酸(59.77%),占脂肪酸的83.14%.侧柏叶子饱和脂肪酸饱和脂肪酸主要为十六烷酸(14.70%)、乙酸(3.20%)、十七烷酸(2.50%);不饱和脂肪酸主要为二十二碳四烯酸(40.48%)、亚油酸(10.69%)、亚麻酸(17.62%).结论:柏子仁和侧柏叶均含有合理的脂肪酸组成.  相似文献   

8.
Seeds of Raphanus sativus L. subjected to accelerated ageing were investigated for reactive oxygen species (ROS) release and for content of vitamin E (tocopherol, TOC, and tocotrienol, TOC-3), fatty acids and phytosterols in seed coats, cotyledons and embryonic axes during germination. In unaged seeds, ROS release occurred mainly in seed coats of non-imbibed seeds and in seedlings (48?h of imbibition). TOC and TOC-3 were mainly represented by the ??-isoform, abundant in embryonic axes. Fatty acids were mainly found in cotyledons. In seed coat and embryonic axis, phytosterols consisted mainly of sitosterols. The effects of ageing were mainly visible in embryonic axes at 48?h of imbibition. Deterioration was associated with a decrease in fresh weight increase percentage, germination percentage, ??-TOC and total fatty acid content. An increase in ROS release from seed coats and in ??-TOC, ??-TOC, ??-TOC-3 content in embryonic axis was also observed. The use of ??-TOC and total fatty acids in embryonic axis as parameters of seed quality evaluation during storage was suggested.  相似文献   

9.
The total mycelial lipid of Aspergillus fumigatus was analysed and over half of its hexahydropolyprenol was shown to be esterified with fatty acids. Comparison of the fatty acid content of the prenyl esters with the sterol ester and the total lipid indicated a marked predominance of saturated fatty acids in the polyprenyl esters. The predominant acids esterified to the prenols were palmitic acid, linoleic acid, oleic acid, lignoceric acid, stearic acid and palmitoleic acid. Most of the unesterified polyprenol was found in the mitochondrial fraction, but the esterified prenol was equally distributed throughout the cell fractions. This distribution was unlike that found for ergosteryl ester in the same tissue.  相似文献   

10.
The seeds of the almond tree [(Prunus dulcis (Mill.) D. A. Webb. (syn. Prunus amygdalus)] were collected in two different periods of maturity and were studied for their lipid content. The total lipids (TL) were extracted by the Bligh-Dyer method and the lipid classes have been isolated by chromatographic techniques and were analyzed by HPTLC coupled with a flame ionization detector (HPTLC/FID) and GC-MS. The oils were found to be rich in neutral lipids (89.9% and 96.3% of total lipids) and low in polar lipids (10.1% and 3.7% of total lipids) for the immature and mature seed oils, respectively. The neutral lipid fraction consisted mainly of triacylglycerides whereas the polar lipids mainly consisted of phospholipids. GC-MS data showed that the main fatty acid for both oils was 9-octadecenoic acid (oleic acid). The unsaturated fatty acids were found as high as 89.4% and 89.7%, while the percentage of the saturated fatty acids was found 10.6% and 10.3% for the immature and mature seed oils, respectively. Liposomes were prepared from the isolated phospholipids using the thin lipid film methodology, and their physical properties were characterized. Cytotoxicity was found absent when assayed against normal and cancerous cell lines. These new formulations may have future applications for encapsulation and delivery of drugs and cosmetically active ingredients.  相似文献   

11.
Changes in membrane lipid components and cellular antioxidant systems were investigated through 7 years in seeds of Acer platanoides L. after storage in natural conditions, i.e. - 3°C and 10% water content. The loss of germination capacity in aged seeds was associated with increased solute leakage during imbibition, reduced content of phospholipids, especially phosphatidylcholine, and increased free fatty acid content. A marked decrease of unsaturated fatty acids in the phospholipid fraction was observed after one year of storage. Antioxidant potential in the lipid fraction and level of -SH groups decreased during storage. The results are consistent with the hypothesis that ageing in seeds is mediated by a free radical mechanism.  相似文献   

12.
We investigated the potential of seaweeds as feedstock for oil‐based products, and our results support macroalgae (seaweeds) as a biomass source for oil‐based bioproducts including biodiesel. Not only do several seaweeds have high total lipid content above 10% dry weight, but in the brown alga Spatoglossum macrodontum 50% of these lipids are in the form of extractable fatty acids. S. macrodontum had the highest fatty acid content (57.40 mg g?1 dw) and a fatty acid profile rich in saturated fatty acids with a high content of C18:1, which is suitable as a biofuel feedstock. Similarly, the green seaweed Derbesia tenuissima has high levels of fatty acids (39.58 mg g?1 dw), however, with a high proportion of PUFA (n‐3) (31% of total lipid) which are suitable as nutraceuticals or fish oil replacements. Across all species of algae the critical parameter of fatty acid content (measured as fatty acid methyl esters, FAME) was positively correlated (R2 = 0.67) with total lipid content. However, the proportion of fatty acids to total lipid decreased markedly with total lipid content, generally between 30% and 50%, making it an inaccurate measure of the potential to identify seaweeds suitable for oil‐based bioproducts. Finally, we quantified within species variation of fatty acids across locations and sampling periods supporting either environmental effects on quantitative fatty acid profiles, or genotypes with specific quantitative fatty acid profiles, thereby opening the possibility to optimize the fatty acid content and quality for oil production through specific culture conditions and selective breeding.  相似文献   

13.
The triglycerides isolated from egg yolk lipids of eggs at various stages of incubation were fractionated according to the degree of unsaturation by argentation chromatography, and individual fractions were analyzed for their fatty acids by gas liquid chromatography. The proportions of the various fractions were constant during development. Fatty acid composition of the fractions were constant also. Fractions with one saturated fatty acid and two monoenoic fatty acids (SM2) constituted over 40% of the total triglyceride. Palmitic acid constituted over 30%, and oleic acid over 45% of the fatty acid of total triglycerides. It is suggested that during development of thick embryo there is no selective utilization of the egg yolk triglycerides.  相似文献   

14.
Two breeding lines of “zero-erucic-acid” rapeseed (Brassica napus) were grown in climate chambers at a constant night temperature (12°C) and constant photoperiod (16 hours) but with different day temperatures (15, 20 and 25°C). Samples of leaves, siliques and immature seeds were analysed for total fatty acid pattern. The content of different acyl lipids and the fatty acid pattern of these lipids were also determined in some of the samples by use of preparative TLC followed by GLC of the fatty acids. The mature seeds produced by ten plants of each selection in each climate were analysed separately for total fatty acid composition. Mono- and digalactosyl diglycerides (MGDG, DGDG) were the predominant acyl lipids in leaves and siliques. In developing seeds they also were more abundant than the phospholipids, but in this case the neutral lipids, mainly triacylglycerols, contained about 95% of the total fatty acids. Large variations were found in the fatty acid composition of monogalactosyl diglyceride and digalactosyl diglyceride, isolated from leaves, siliques and immature seeds. The palmitic acid content of leaf MGDG was about 15 %, atypically high for MGDG from photosynthetic tissue. The linolenic acid content of the MGDG was about 45 %, 30 % and 10 % in the leaf, silique and seed tissues respectively. A hexadecatrienoic acid (16: 3) was found almost exclusively in the MGDG samples of leaves, siliques and immature seeds (about 25 %, 10 % and 3 % 16:3 respectively). The lipids of siliques — mainly photosynthetising tissue — were different from those of leaves and had especially high contents of stearic acid (6–12 % in the different lipids). For all lipid classes studied, leaves grown at the lowest day temperature had a slightly lower oleic and higher linolenic acid content than those grown at the highest temperature. On the other hand, increasing the day temperature caused a decreased level of oleic, an increased level of linoleic and an essentially unchanged level of linolenic acids in the mature seeds from both selections.  相似文献   

15.
The aim of this study was to determine the temporal release of fatty acids and sugars from corn and cucumber seeds during the early stages of seed germination in order to establish whether sugars found in exudate can prevent exudate fatty acid degradation by Enterobacter cloacae. Both saturated (long-chain saturated fatty acids [LCSFA]) and unsaturated (long-chain unsaturated fatty acids [LCUFA]) fatty acids were detected in corn and cucumber seed exudates within 15 min after seed sowing. LCSFA and LCUFA were released at a rate of 26.1 and 6.44 ng/min/seed by corn and cucumber seeds, respectively. The unsaturated portion of the total fatty acid pool from both plant species contained primarily oleic and linoleic acids, and these fatty acids were released at a combined rate of 6.6 and 0.67 ng/min/seed from corn and cucumber, respectively. In the absence of seed exudate sugars, E. cloacae degraded linoleic acid at rates of 29 to 39 ng/min, exceeding the rate of total fatty acid release from seeds. Sugars constituted a significant percentage of corn seed exudate, accounting for 41% of the total dry seed weight. Only 5% of cucumber seed exudate was comprised of sugars. Glucose, fructose, and sucrose were the most abundant sugars present in seed exudate from both plant species. Corn seeds released a total of 137 microg/seed of these three sugars within 30 min of sowing, whereas cucumber seeds released 0.83 microg/seed within the same time frame. Levels of glucose, fructose, and sucrose found in corn seed exudate (90 to 342 microg) reduced the rate of linoleic acid degradation by E. cloacae to 7.5 to 8.8 ng/min in the presence of either sugar, leaving sufficient concentrations of linoleic acid to activate Pythium ultimum sporangia Our results demonstrate that elevated levels of sugars in the corn spermosphere can prevent the degradation of LCUFA by E. cloacae, leading to its failure to suppress P. ultimum sporangial activation, germination, and subsequent disease development.  相似文献   

16.
In vitro examinations of the effect of saturated fatty acids on skeletal muscle insulin action often use only one or two different fatty acid species, which does not resemble the human plasma fatty acid profile. We compared graded concentrations (0.1-0.8mM) of 3 different lipid mixtures: 1) a physiologic fatty acid mixture (NORM; 40% saturated fatty acids), 2) a physiologic mixture high in saturated fatty acids (HSFA; 60% saturated fatty acids), and 3) 100% palmitate (PALM) on insulin signaling and fatty acid partitioning into triacylglycerol (TAG) and diacylglycerol (DAG) in cultured muscle cells. As expected, PALM readily impaired insulin-stimulated pAktThr308/Akt and markedly increased intracellular DAG content. In contrast, the fatty acid mixtures only modestly impaired insulin-stimulated pAktThr308M/Akt, and we found no differences between NORM and HSFA. Importantly, NORM and HSFA did not increase DAG content, but instead dose-dependently increased TAG accumulation. Therefore, the robust impairment in insulin signaling found with palmitate exposure was attenuated with physiologic mixtures of fatty acids, even with a very high proportion of saturated fatty acids. This may be explained in part by selective partitioning of fatty acids into neutral lipid (i.e., TAG) when muscle cells were exposed to physiologic lipid mixtures.  相似文献   

17.
The species Perna viridis is a highly consumed species, which fast growth makes it an interesting aquaculture alternative for Venezuelan and Trinidad coasts. With the aim to contribute with its nutritional value information, this study analyzed lipid and fatty acid contents from samples taken in five locations from Eastern Venezuela and three from Trinidad West Coast. Total lipids were extracted and quantified, from a pooled sample of 100 organisms per location, by standard gravimetric methods, and their identification and quantification was done by TLC/FID (Iatroscan system). Furthermore, the esterified fatty acids of total lipid, phospholipids and triacylglycerols were identified and quantified by gas chromatography. Eastern Venezuela samples from Los Cedros, La Brea and Chaguaramas showed the highest total lipid values of 7.92, 7.74 and 7.53, respectively, and the minimum values were obtained for La Restinga (6.08%). Among lipid composition, Chacopata samples showed the lowest phospholipid concentration (48.86%) and the maximum values for cholesterol (38.87%) and triacylglycerols (12.26%); besides, La Esmeralda and Rio Caribe samples exhibited maximum phospholipids (88.71 and 84.93 respectively) and minimum cholesterol (6.50 and 4.42%) concentrations. Saturated fatty acids represented between 15.04% and 65.55% within total lipid extracts, with maximum and minimum values for La Esmeralda and Chacopata, respectively. Polyunsaturated results resulted between 7.80 and 37.18%, with higher values in La Brea and lower values in La Esmeralda. For phospholipids, saturated fatty acids concentrations varied between 38.81 and 48.68% for Chaguaramas and Chacopata samples, respectively. In the case of polyunsaturated fatty acids, these varied between non detected and 34.51%, with high concentrations in Los Cedros (27.97%) and Chaguaramas (34.51%) samples. For the triacylglycerols, the saturated fatty acids composition oscillated between 14.27 and 53.80% with low concentrations for Chacopata and high concentration for La Restinga; the polyunsaturated fatty acids were between 4.66 and 35.55% with lower values for Chacopata and higher values for Chaguaramas samples. P. viridis is recommended for human being consumption, according to the high content of unsaturated fatty acids found for this species.  相似文献   

18.
Adipose lipid obtained from fed rats 15 or 60 min after injection of radioactive glucose was separated into 10 triglyceride classes of differing fatty acid compositions. The distribution among these classes of total and radioactive triglyceride-glycerol was determined and found to be the same. Thus newly synthesized adipose triglycerides resemble in kind and proportion the triglycerides which exist in the tissue. This finding is in accord with the concept that the structures of adipose triglycerides are stable over long periods and that the turnover rate of the several triglyceride species are similar. After administration of radioactive glucose, the specific activity of saturated fatty acids was higher in the more saturated triglyceride species. These data indicate that newly formed saturated acids do not mix completely with all adipose tissue fatty acids available for esterification. Fatty acids derived from plasma triglyceride influenced the composition of newly synthesized adipose tissue triglyceride and thus constitute an important source of adipose tissue lipid.  相似文献   

19.
Reports on lipid composition of peripheral nervous system have generally been restricted to the saturated fatty acids of the endoneurium. In this work we attempt to determine the fatty acid composition of the different lipid classes in both endo- and perineurium from sciatic nerve microdissection on adult rats. Unsaturated fatty acids were found to make up around 60% of total fatty acids in samples of endoneurium and perineurium, with monounsaturated fatty acids forming 40-50% of total unsaturated fatty acid content. Although the same fatty acids were present in both tissues there was a striking difference in C 18:1 (n-9) and C 18:2 (n-6) ratio between endoneurium and perineurium, which is particularly rich in linoleic acid. The nonpolar perineurial lipids were found to be richest in linoleic acid. Phospholipids were present in the perineurium, and they contained high proportions of saturated and medium-chain monounsaturated fatty acids.  相似文献   

20.
1. Lipid extracts were obtained from castor-bean endosperm tissue at various times during germination and, after purification, the total lipid content was determined. Quantitative measurements of the triglyceride and phospholipid content together with the fatty acid composition were made. 2. The total lipid content of the endosperm rapidly decreased during germination; after 10 days less than 20% of the original weight of lipid remained. In contrast, the phospholipid content (initially less than 0.5% of the total lipid) increased slightly during this time. The fatty acid composition and the relative proportions of the triglyceride species of the total lipid extract remained constant during 10 days of germination. 3. Gibberellic acid (0.3 mM) markedly stimulated the rate of lipid breakdown but did not alter either the fatty acid composition or the relative proportion of triglyceride species. 4. The embryo had little effect on lipid metabolism in the endosperm tissue; only after 6 days of germination were differences observed in the rate of fat utilization in the presence and absence of the embryo.  相似文献   

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