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1.
The antioxidant capacity of seed phosphatides and synthetic antioxidants when compared in cow ghee was found to be in the order: phosphatidyl ethanolamine < propyl gallate <palmitoyl ascorbate <butylated hydroxy anisole < phosphatidyl choline. Phosphatidyl ethanolamine was found to be the most effective antioxidant. Cow ghee had less peroxide development than buffalo ghee. The ghee prepared at 100°C was more stable against peroxide development compared with that prepared at 50°C. These observations were supported by the analysis of ghee samples for peroxide values and for fatty acids. The phosphatides imparted more antilipolytic activity to ghee then to synthetic antioxidants.  相似文献   

2.
Berseem seed oil was fractionated into non-polar and polar components. Tentative identification was made of hydrocarbons, sterol esters, triglycerides, free fatty acids and partial glycerides in the non-polar fraction and of lysophosphatidyl choline, phosphatidyl inositol, lysophosphatidyl ethanolamine, phosphatidyl choline, phosphatidyl glycerol, phosphatidyl ethanolamine, digalactosyl diglycerides, sterol glycosides, phosphatidic acid, monogalactosyl diglycerides, cerebrosides and esterified sterol glycosides in the polar fraction. The fatty acid constituents of the major polar and of all the non-polar lipid components are also reported.  相似文献   

3.
The lipid classes, fatty acids and sterols of the mesocarp, seed and pollen lipids of five species of Raphia palms endemic to Nigeria were analysed. Apart from quantitative differences in the fatty acid compositions, chromatographic analyses demonstrated very little change in the patterns of the characteristic lipids associated with either the mesocarps, seed endosperms or pollens. Mesocarp lipids contained mainly triglycerides, while palmitic, oleic and linoleic acids were the major acids. Contrary to published data for seed lipids, Raphia seed endosperms contained a relatively small amount of triglycerides and a high proportion of polar lipids. Fatty acids associated with this tissue were not only highly unsaturated, but were significantly different from typical fatty acids of seed lipids. Raphia pollens, on the other hand, showed a complex array of lipid types. Triglycerides, sterols and sterol esters constituted the main neutral lipids while phosphatidyl choline, phosphatidyl inositol, phosphatidyl ethanolamine and galactosyl diglycerides represented the polar fraction. Apart from minor trends, palmitic, oleic and linoleic acids constituted the major fatty acids in all species. The biological importance of the steroidal sapogenins found in all organs is discussed.  相似文献   

4.
Edible shrimp (Penaeus aztecus) tissue contains approximately 1.2% extractable lipids, the majority of which are phospholipids. Data from the gravimetric quantitation of lipid classes isolated by column chromatography indicated that phosphatidyl choline was the predominant phospholipid and cholesterol the predominant neutral lipid in edible shrimp tissue. Fatty acid distribution data indicated that sphingomyelins contained the greatest percent by weight of unsaturated fatty acids while cholesterol esters contained the greatest proportion of saturated fatty acids. Enzymatic hydrolysis followed by gas liquid chromatography of phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine indicated that fatty acids located at the β position were more highly unsaturated than those at the α position.  相似文献   

5.
Neutral lipids of fresh chicken breast muscles are shown to be triglycerides, sterols and sterol esters with only traces of mono- and diglycerides and free fatty acids. Phospholipids include measurable quantities of phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl inositol, phosphatidyl serine, sphingomyelin, diphosphatidyl glycerol, lysophosphatidyl choline and lysophosphatidyl ethanolamine. Fatty acid analyses of several of the lipid fractions are also included. Decreases in phosphatidyl choline and phosphatidyl ethanolamine coupled with increases in lysophosphatidyl choline, lysophosphatidyl ethanolamine and free fatty acids after 48 hr postmortem in the cold indicate phospholipase A activity concurrent with other postmortem changes. The significance of the results is discussed.  相似文献   

6.
The effect of three nitrogen sources on the chemical composition of seven fungi, namely: Aspergillus niger, A. luchuensis, Penicillium crustosum, Alternaria tenuis, Rhizoctonia solani, Mucor sp. and Pythium irregulare has been studied. The various fungi showed a great variation with respect to lipid percentage and total lipid content. Lipid content varied from 3.2 to 41.5%. Non-polar lipids were comprised of monoglycerides, diglycerides, free sterols, free fatty acids and triglycerides. The quantitative make-up of the non-polar lipid varied with different nitrogen sources. Palmitic, stearic, oleic and linoleic acids were the major fatty acids while lauric, myristic, palmitoleic, linoleic and arachidic were the minor ones. The fatty acid composition was dramatically changed by changing the nitrogen source. Since different fungi responded differently to changes in nitrogen source, no generalisation could be made. Two-dimensional thin-layer chromatography of the polar lipid fraction of these fungi revealed the presence of a maximum of fifteen spots. Phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl inositol were the major spots while lysophosphatidyl choline, lysophosphatidyl ethanolamine and phosphatidyl glycerol were present in smaller quantities. In comparison to phospholipids, glycolipids (except sterol glycoside) were present in relatively lower concentration. Pythium irregulare was very characteristic in having no glycolipids at all.  相似文献   

7.
The fatty acid composition has been determined on phosphatidyl choline, phos-phatidyl ethanolamine and sphingomyelin fractions earlier isolated from the rumen and abomasum tissues of foetal and of adult Romney sheep. The major proportion of polyunsaturated fatty acids was found in the phosphatidyl ethanolamine (17 to 43%) fraction and this was reduced in the phosphatidyl choline (7 to 25%) and sphingomyelin (1 to 4%) fractions. These features are in keeping with the results for mammalian tissues generally. The phosphatidyl ethanolamine fractions were further characterised by the low content of palmitic acid (<8%) compared with 25 to 30 % in the phosphatidyl choline fractions and 29 to 52% in the sphingomyelin fractions and by the occurrence of cyclopropane fatty acids. Consistent with the findings of other workers on mammalian tissues, the sphingomyelin fractions contained a relatively high content (16 to 27%) of higher w-saturated fatty acids including 22:0,23:0,24:0 and 25:0 and of tetracos-14-enoic (24:1 ω9) acid (5 to 16%). The total amounts of acids above C20 tended to vary inversely with the levels of palmitic acid whereas the levels of stearic acid were relatively constant at 13 to 17%. Changes in fatty acid composition with age were generally not marked but the tissues of the foetus were distinguished from those of the foetus were distinguished from those of the adult by their substantial amount of eicosa-5,8,11-trienoic (20:3 ω9) acid together with relatively low contents of linoleic (18:2 ω6) and linolenic (18:3 ω3) acids and to a leser extent by reduced level of acids of the ω3 series. This was particularly reflected by the ratios of ω6/ω3 C20 + C22 acids in the phosphatidyl ethanolamine fractions, the valucs for the foetal rumen and abomasum tissues being 1.03 and 1.07, respectively, compared with corresponding values of 0.78 and 0.72 found in adult sheep. The results are consistent with a requirement for C20 and C22 polyunsaturated acids of the ω3 and ω6 series and some penetration of maternal fatty acids through the placenta. The resemblance between the fatty acid make-up and composition of foetal and maternal phospholipids suggests the possibiligy of transference of intact or lyso-phospholipids from the mother to the foetus through the placenta. However, such a possibility is counter-indicated by consideration of previous work using labelled intermediates and by the mechanism of conversion of linoleic and linolenic acids requiring their CoA derivatives in the formation of the corresponding polyunsaturated C20 + C22 acids. Nevertheless, the sharp cut-off of exogenous maternal fatty acids from the foetal triglycerides and their inclusion in the foetal phospholipids are not readily explainable.  相似文献   

8.
Lipids were extracted from a single sample of wheat flour using three solvent systems: ethanol–diethyl ether–water (2:2:1 by vol.); chloroform–methanol (2:1 by vol.); and water-saturated n-butanol. Analysis of the extracts and of residual lipid in the extracted flour showed that water-saturated n-butanol was the most efficient solvent. Wheat-flour lipids were extracted with water-saturated n-butanol and separated by chromatographic procedures into individual components. The lipid classes which were isolated and studied were steryl ester, free sterol, 6-O-acyl steryl glucoside, steryl glucoside, triglyceride, diglyceride, monoglyceride, free fatty acid, monogalactosyl diglyceride, 6-O-acyl monogalactosyl diglyceride, digalactosyl diglyceride, digalactosyl monoglyceride, monoglycosyl ceramide, diglycosyl ceramide, N-acyl phosphatidyl ethanolamine, N-acyl lysophosphatidyl ethanolamine, phosphatidyl ethanolamine, lysophosphatidyl ethanolamine, phosphatidyl choline, lysophosphatidyl choline, phosphatidyl serine and phosphatidyl inositol. Monogalactosyl monoglyceride was also tentatively identified. The quantitative distributions of the lipid classes were determined. Monoglycosyl ceramide contained small amounts of normal fatty acids (12:0–24:0) and large amounts of 2-hydroxy fatty acids (principally 16:0 and 20:0), with similar amounts of dihydroxy long-chain bases (18:0 and 18:1) and trihydroxy long-chain bases (18:0, 18:1, 19:0, 19:1, 20:0, 22:0). The principal sterols were identified as β-sitosterol, campesterol, and C28 and C29 saturated sterols. The fatty acids in the sterol lipids were principally 16:0 (50–60%) and 18:2 (28–30%) with small amounts of 16:1, 18:0, 18:1 and 18:3. The fatty acids in all the glycerides were principally 18:2 (51–84%) with lesser amounts of 16:0, 18:0, 18:1 and 18:3.  相似文献   

9.
The ethanolamine phospholipids of beef, lamb, pork and chicken examined in this study contained over 40% of ethanolamine plasmalogen, whereas fish contained only 13%. The level of choline plasmalogen in choline phospholipids was less than 1% in fish and ranged from 10 to 30% in the other four meats. Palmitaldehyde was the major fatty aldehyde in the choline plasmalogens of beef, lamb, pork and chicken (65–80% of total aldehydes), but was present at lower levels in the ethanolamine plasmalogens. The per cent fatty acid compositions of phosphatidylethanolamine and the corresponding ethanolamine plasmalogen were very similar, being typically low in palmitic acid but very high (56–74%) in polyunsaturated fatty acids. The fatty acids of the choline plasmalogens contained more polyunsaturated fatty acids than the corresponding phosphatidyl cholines, but at lower levels than in the fatty acids of the ethanolamine phospholipids.  相似文献   

10.
The lipid and fatty acid compositions of five Indian species of prawns, Metapenaeus monoceros, M. dobsoni, M. affinis, Penaeus indicus and Parapenaeopsis stylifera, were examined. Phospholipids constituted 50–70% of the total lipids, with phosphatidyl choline (50%) and phosphatidyl ethanolamine (29%) as their chief components. Unsaponifiable matter comprised 21–40%, chiefly cholesterol: triglycerides only constituted 9–14.5%. In the total lipids (I.V. 90–112), saturated, monoenoic and polyenoic fatty acids averaged 42, 24 and 34%. Palmitic acid is high, oleic low, and 20:5 generally, but not always, higher than 22:6. The only brackish water prawn, M. monoceros, though generally in conformity, was distinctive in several respects.  相似文献   

11.
Lantern fish of the species Lampanyctodes hectoris were shown to contain phospholipids (10 g kg?1) and non-phosphorylated lipids (140 g kg?1). The phospholipid fraction consisted of phosphatidyl choline (47% of total phospholipids), phosphatidyl ethanolamine (42%), phosphatidyl serine (3%), phosphatidyl inositol (1%), sphingomyelin (4%), lyso-phosphatidyl choline (1%) and cardiolipins (2%). Lantern fish (L hectoris) meals normally contain unacceptably high lipid contents (150 g kg?1 and over); this characteristic was found not to be due to a high phospholipid level in the lantern fish. The major fatty acid of the phospholipids was C22:6n-3 (25% total fatty acids) followed by C16:0 (18%), C18:ln-9 (16%) and C20:5n-3 (8%). This distribution was different from that of the non-phosphorylated lipids where the major fatty acid was C16:0 (21%) followed by C18:ln-9 (19%), C20:5n-3 (11%), C20:l (7%) and C22:6n-3 (7%). The lantern fish press oil and residual meal lipids had fatty acid distributions similar to those of the non-phosphorylated lipids.  相似文献   

12.
In this study, changes in fatty acid distributions of pumpkin seeds (Cucurbita spp) in the course of the roasting process were investigated. Whole pumpkin seeds were exposed to microwaves for 6, 12, 20 or 30 min at a frequency of 2450 MHz. The kernels were separated from the seeds, and the lipid components and the fatty acid distributions of triacylglycerols (TAGs) and phospholipids (PLs) were analysed by a combination of thin layer chromatography and gas chromatography. Major lipid components were TAGs, free fatty acids (FFAs) and PLs, while steryl esters and diacylglycerols were also present in minor proportions. The greatest PL losses (p < 0.05) were observed in phosphatidyl ethanolamine, followed by phosphatidyl choline or phosphatidyl inositol. With a few exceptions, significant differences (p < 0.05) in fatty acid distributions occurred when the seeds were microwaved for 20 min or more. Nevertheless, the positional characteristics of fatty acid distributions in the TAGs were still retained after 20 min of roasting: unsaturated fatty acids were predominantly concentrated in the sn‐2‐position, and saturated fatty acids primarly occupied the sn‐1‐ or sn‐3‐position. These results suggest that no significant changes in fatty acid distribution of TAGs and PLs would occur within 12 min of microwave roasting, thus ensuring that a good‐quality product would be obtained. Copyright © 2005 Society of Chemical Industry  相似文献   

13.
Isolation and characterization of whey phospholipids   总被引:4,自引:0,他引:4  
A freeze-dried whey powder was produced by microfiltration of Cheddar cheese whey. A 0.2-micron ceramic membrane in a stainless steel housing unit was used to concentrate components > 400 kDa present in the whey. The experimental whey powder, derived from Cheddar cheese whey, and a commercial whey powder were subjected to proximate analysis, lipid classes, phospholipid classes, and fatty acid compositional analyses. Commercial whey powder and commercial soybean lecithin were subjected to an alcohol fractionation procedure in an effort to alter the ratio of phosphatidyl choline to phosphatidyl ethanolamine and the functionality of dairy phospholipids. The fractionation procedure produced an alcohol-insoluble fraction containing 84% phosphatidyl ethanolamine, whereas the alcohol-soluble fraction resulted in a decrease in the phosphatidyl choline to phosphatidyl ethanolamine ratio. The commercial whey contained a higher ratio of phospholipids to neutral lipids compared with the experimental whey. The classes of phospholipids present within the two wheys were similar, whereas the experimental whey contained a phosphatidyl choline content twice that of the commercial whey, and the phospholipids composition of both wheys differed from the milk fat globule membrane. Comparison of the phospholipids and fatty acid composition of the wheys with the soy lecithin revealed that although the wheys were similar to each other, they differed from the soy lecithin in both the classes of phospholipids present and in the fatty acid composition. These compositional differences may influence the functionality of whey phospholipids.  相似文献   

14.
The phospholipids of mussels (Mytilus edulis Linne) from the coast of Qingdao were extracted, fractionated and analysed over a 12 month period. The contents of total lipids, neutral lipids, polar lipids and phospholipids were measured. The composition of phospholipids was determined by high‐performance liquid chromatography, and their fatty acid composition was analysed by gas chromatography. The phospholipid content ranged from 3.6 to 6.4 g kg?1 soft tissue. PE (phosphatidyl ethanolamine) and PC (phosphatidyl choline) were the major constituents. C16:0, C20:5 and C22:6 were the major fatty acids. C20:5 (5.25–23.10%) and C22:6 (6.05–20.42%) varied regularly with the seasonal factors. Their total amounts were high from January to June, which would be an optimal time for the utilisation of the phospholipids of mussels. © 2002 Society of Chemical Industry  相似文献   

15.
Two improved strains of Pennisetum typhoideum (‘bajra’) were found to have a free lipid content of about 5.0% and bound lipid content of about 0.5%. In the non-polar fraction, sterol esters and hydrocarbons, triglycerides, free fatty acids, free sterols and partial glycerides were present with triglycerides as the principal constituents. Polar lipids were separated by two-dimensional thin-layer chromatography and lecithin was found to be the major component. Sterol-containing glycolipids (sterol glycosides and esterified sterol glycosides) were present in appreciable amounts. Phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl inositol, lysophosphatidyl ethanolamine, lysolecithin, phosphatidic acid, poly-glycerophosphatide, mono- and di-galactosyl glycerides and cerebrosides have also been tentatively identified.  相似文献   

16.
Phospholipids of the abalone were separated into component fractions by chromatography on silicic acid. The phospholipids were remarkable for the presence (6%) of an unusual sphingolipid liberating 2-amino-ethylphosphonic acid on hydrolysis, and for the high proportion of plasmalogens (23%). The presence of phosphatidyl ethanolamine plus ethanolamine plasmalogen (32%), phosphatidyl serine (5%), phosphatidyl inositol (5%), phosphatidyl choline (41%) and sphingomyelin (1%) were also demonstrated. The fatty acid distribhion in the phospholipids, the non-phosphorylated lipids and the unusual sphingolipid was determined by gas chromatography. In general these results show a similarity between the phospholipid and the non-phosphorylated lipid fatty acids, the former being richer in long chain polyunsaturated fatty acids. Fatty acids of the unusual sphingolipid were outstanding for the high palmitic (53%) and stearic acid (15%) content.  相似文献   

17.
Supercritical carbon dioxide (SC‐CO2) extractions (with and without ethanol as an entrainer) were carried out to remove lipids and pigments from protein concentrate of green algae (Scenedesmus obliquus) cultivated under controlled conditions. The content and fatty acid composition of algal lipids using column, thin‐layer (TLC) and gas‐liquid chromatography (GLC) were determined. Absorption spectra of extracted fractions showed the predominance of chlorophyll A (λmax at 410nm). Single step supercritical carbon dioxide (SC‐CO2) extraction resulted mostly in removal of neutral lipids and a part of glycolipids, but phospholipids were not extracted. Addition of ethanol to SC‐CO2 increased the amount of glycolipids and phospholipids in the extract. TLC pattern of algal lipids showed that the main part of neutral lipids consisted of diglycerides, triglycerides, hydrocarbons, free sterols, and sterol esters. The glycolipids were mostly monogalactosyl diglyceride, digalactosyl diglyceride, esterified sterol glycoside, and sterol glycoside. In phospholipids, phosphatidyl choline, phosphatidyl glycerol, and phosphatidyl ethanolamine were the main compounds. Fatty acid composition patterns indicated the main fatty acids to be 16:0, 16:1, 16:2, 16:3, 16:4, 18:1, 18:2 and 18:3(a). Relatively high recovery of polyunsaturated fatty acids and essential fatty acids in supercritical fluid extracted algal lipids and protein isolates were observed.  相似文献   

18.
Certain aspects of lipid metabolism in Fusarium oxysporum were studied using acetate-1-C14 and H3P32O4 for incorporation of radioactivity into the fungal mycelium. During initial stages of growth of the organism (up to 1 h of incubation) the phospholipid fraction exhibited relatively higher specific activity values indicating its rapid rate of synthesis. Higher turnover rates were observed for phosphatidic acid (PA) and polyglycerophosphatides (PGP). It is postulated that PGP represents a labile pool where PA synthesised in excess of the metabolic needs of the cell is stored to be subsequently used during periods of intense phospholipid biosynthesis. In pulse and chase experiments, higher specific activities were observed for PA, PGP and cardiolipin (CL) fractions after 1-day chase on unlabelled media. Rapid turnover rates were observed for PA, PGP and cardiolipin (CL) fractions. It is suggested that these are involved in the growth of new cells and (or) in the cell repair processes. In cells grown both under normal and carbon-starvation conditions, the specific activity pattern of phosphatidyl choline (PC), and phosphatidyl ethanolamine and phosphatidyl glycerol (PE + PG measured collectively) was very similar indicating similarity in the metabolism of these two classes of phosphatides. Addition of sodium arsenite, alloxan, p. benzoquinone and citric acid in the incubation media was found to affect the synthesis of lipid classes in different ways. For example, among the polar lipids, PA, PC, PE + PG, CL and SGP + FFA fractions were inhibited by p.benzoquinone, while the incorporation of label from C14 was found to be stimulated into the phosphatidyl inositol fraction.  相似文献   

19.
The effects of heating at 132°C on the fatty acids and fatty aldehydes of neutral lipids and phospholipids of lean beef, veal, lamb, pork and chicken were studied. Heating caused hydrolysis of the plasmalogens in the phospholipids, and varying amounts of the liberated fatty aldehydes were recovered in the neutral lipid fractions. Beef phosphatidyl choline lost more polyunsaturated fatty acids than that of the other meats. Beef and veal phosphatidyl ethanolamine lost more polyunsaturated fatty acid than that of lamb, pork or chicken, but the effect was obscured by the influx of fatty acids from elsewhere into this fraction after heating.  相似文献   

20.
Fatty acid profiles and distribution of individual phospholipids (PL) in the total PL were determined in chicken meat and skin and swine aortas, and the contribution of each PL to malondialdehyde (MDA) formation was studied. Results indicate that phosphatidyl choline (PC) and phosphatidyl ethanolamine (PE) produced 70-77% of the total PL MDA while 16-25% of the MDA was formed by phosphatidyl inositol (PI) and phosphatidyl serine (PS). Much lower concentrations of MDA (3-6%) were formed by sphingomyelin (SP), cardiolipin (CL) and lysophosphatidyl choline (LyPC). In all analyzed tissues, both the MDA concentration and the percentage of polyenoic fatty acids, especially arachidonic acid, were highest in PI followed by PE, PS, PC, CL LyPC, and SP.  相似文献   

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