首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Total lipids extracted from Cumin (Cuminum cyminum L., Umbelliferae) amounted to 14.5% of the dry seeds. The total lipids consisted of 84.8% neutral lipids, 10.1% glycolipids, and 5.1% phospholipids. Neutral lipids consisted mostly of triacylglycerols (89.4%) and small amounts of diacylglycerols, free fatty acids, sterols, sterolesters, and hydrocarbons. At least five glycolipids and five phospholipids were identified. Acylmonogalactosyldiacylglycerol and acylatedsterylglucoside were the major glycolipids, while monogalactosyldiacylglycerol, monogalactosylmonoaclycerol, and digalactosyldiacylglycerol were present in small quantities. Phosphatidylethanolamine and phosphatidylcholine were the major phospholipids, while phosphatidylinositol, lysophosphatidylethanolamine, and phosphatidylglycerol were present in small amounts. The fatty acid composition of these different neutral lipids, glycolipids, and phospholipids was determined  相似文献   

2.
Total kernel lipids (TL) in Alphonso mango (Mangifera indica) extracted amounted to 11.6% of the dry kernel. The TL consisted of 96.1% neutral and 3.9% polar lipids which comprised 2.9% glycolipids and 1.0% phospholipids. At least six glycolipids and six phospholipids were identified. Acyl-monogalactosyldiacylglycerol, monogalactosyldiacylglycerol, and digalactosylmonoacylglycerol were the major glycolipids, while acylated stearyl glucoside, monogalactosylmonoacylglycerol and digalactosyldiacylglycerol were present in small quantities. The phospholipids consisted of: phosphatidic acid, phosphatidylcholine and phosphatidylinositol as major phospholipids and minor amounts of phosphatidylglycerol, phosphatidylethanolamine and lysophosphatidylethanolamine. The fatty acid composition of these different glycolipids and phospholipids was determined.  相似文献   

3.
Hake mince was stored in frozen condition at ?5°C, ?18°C and ?40°C. Samples were withdrawn periodically, and the lipids were extracted and analysed for free fatty acid and phosphorus (P) content. The free fatty acid contents were corrected for the presence of acidic phospholipids and converted into genuine free fatty acid contents. The results at ?5°C and ?18°C showed an initial rapid surge of free fatty acid formation with a concomitant decrease in P content, followed by a second phase of slower free fatty acid generation and loss of lipid-P. At ?40°C only one phase of free fatty acid generation and loss of lipid-P was observed. The rates of the enzymic hydrolyses of the phospholipids and the neutral lipids were calculated at the three temperatures. An Arrhenius plot showed that the decrease in rate of free fatty acid formation with decreasing temperature was greater for the phospholipids than for the neutral lipids. In the rapid and more important phase, the two rates were identical at about ?12°C while above this temperature the phospholipids hydrolysed faster and below it the neutral lipids. Activation energies for the enzymic hydrolyses were calculated.  相似文献   

4.
The lipid composition and fatty acid profile in neutral and polar fraction was determined by TLC-Iatroscan, and Gas Chromatography, in shark oil obtained from a pool of livers from the following species: Ginglimostoma cirratun, Carcharhinus longimanus, and C. falciformis captured in Cuban waters. Two processes, emulsification, and microencapsulation were applied to increase oil stability. The fatty acid profile was obtained for emulsion and microencapsulated oil and the effect of applied treatments was evaluated. Shark oil composition was mainly Triglycerides (97.2%) and a small concentration of phospholipids (0.3%). Twenty-one fatty acids were identified in neutral fraction, and 18 in polar fraction, polyunsaturated ones represented 26.5% of total lipids in the liver oil. Emulsification and microencapsulation processes do not significantly affect fatty acid shark oil composition, in contrast they reduce oxidation, and increase oil stability.  相似文献   

5.
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   

6.
研究了不同糖添加量(3%、6%、9%、12%,m/m)对广式腊肠脂质降解的影响规律。将广式腊肠中瘦肉和肥丁分别进行研究,利用固相萃取技术将脂质分为中性脂肪、磷脂和游离脂肪酸,采用气质联用分析中性脂肪和磷脂的脂肪酸组成、游离脂肪酸的组成及含量。结果表明:磷脂是广式腊肠中脂质降解的主要成分,中性脂肪也对游离脂肪酸的释放有一定作用;瘦肉部分的脂质是腊肠脂质降解的主要部分。糖添加量对中性脂肪和磷脂的多不饱和脂肪酸组成比例具有显著影响,糖添加量低时多不饱和脂肪酸组成比例高,尤其是对瘦肉部分的磷脂影响最为显著,糖添加量为12%时其比例为17.88%,而添加量为6%和3%时分别变为36.70%和33.94%;游离脂肪酸含量随糖添加量的减少而降低,表明糖对腊肠的脂质降解具有一定促进作用。由于多不饱和脂肪酸极易氧化导致其组成比例较低。  相似文献   

7.
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   

8.
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   

9.
The lipid content and fatty acid profiles of seven lesser known protein foods in Nigeria, which include raffia palm and oil palm weevils (Rhynchophorus sp.), shrimps (Palaemonetes sp.), periwinkles (Pachynelania byronesis), snails (Vicapara quadrata), tropical oysters (Thais haemastrama) and crayfish (Palaemonetes varians), were determined. The total lipid content (% fresh weight, FW) ranged between 1.8 ± 0.1 and 9.8 ± 0.1. The range of values for neutral lipids, total phospholipids, and glycolipids (mg/g FW) was 10.1 ± 0.7 to 53.6 ± 1.5, 6.1 ± 1.3 to 30.1 ± 1.5, and 2.5 ± 0.2 to 13.1 ± 0.9, while those of total cholesterol and triacylglycerol content (mg/g neutral lipids) were 1.4 ± 0.1 to 7.1 ± 0.2 and 8.3 ± 1.1 to 47.0 ± 1.5, respectively. Crayfish and palm weevils contained higher amounts of total cholesterol and phospholipids, compared with the rest of the foods. The fatty acid profiles showed variation among the different foods. Palm weevils, periwinkles, snails and tropical oysters were shown to contain substantial amounts of essential fatty acids, especially linolenic acid (C18:3n3).  相似文献   

10.
Milk samples from five commercial dairy herds having severe problems with spontaneous oxidised flavour (SOF) and milk samples from five herds without such problems were analysed for parameters connected with SOF in milk. The study was directed towards analysing parameters which primarily are influenced by feeding. The fatty acid compositions of both neutral lipids and phospholipids were determined as well as the concentrations of α-tocopherol, β-carotene and copper in the milk. The samples were also analysed by dynamic headspace GC to determine volatile oxidation products. The results showed that the reasons for the occurrence of SOF in a specific herd are still obscure, since the only consistent result found for the five control herds, when compared with the corresponding experimental herd, was a higher proportion of the 18:1 trans fatty acid. However, within the affected herds, the difference between cows giving milk with off-flavour and cows giving milk without off-flavour was quite clear. In four out of five herds the ratio between antioxidants and fatty acid unsaturation was lower in milk with off-flavour, and in the fifth herd an extremely high proportion of 18: 2 in the phospholipids seemed to have been the reason for the off-flavour that developed. One of the herds also had a higher copper content in milk showing SOF. The data showed differences in importance of α-tocopherol and β-carotene, in different herds. Also the unsaturation in fatty acids of both neutral lipids and phospholipids had different importance for the flavour stability in different herds. © 1998 SCI.  相似文献   

11.
Lipid and Fatty Acid Composition of Selected Fungi Grown on Whey Medium   总被引:4,自引:0,他引:4  
The molds Aspergillus nidulans, Penicillium frequentans, and Fusarium lycopersicum were tested for lipid production when grown on a deproteinized whey medium. F. lycopersicum produced highest total lipid (38.56%) followed by A. nidulans LC-1 (16.90%) and P. frequentans (10.53%). Triglycerides and phospholipids were the predominant components in the neutral lipid fraction followed by partial glycerides, free fatty acids and nonsaponifiable matter. Phospholipid content was highest in P. frequentans. Palmitic, stearic, oleic and linoleic acids were the major fatty acids and their relative concentrations varied among the three fungi. Lower chain fatty acids were absent.  相似文献   

12.
Abstract: The stereospecific positional distribution of fatty acids of camellia seed oil (also called camellia oil) was determined. The camellia oil was mainly composed of neutral lipids (88.2%), and the oleic acid (86.3%) was found to be a major fatty acid of neutral lipids. In the glycolipids and phospholipids, the oleic acid was also found to be a major fatty acid at 62.5% and 54.2%, respectively. The oleic acid was distributed abundantly in all sn‐1, 2, and 3 positions. It was found that the oleic acid was present more at sn‐2 (93.6%) and 3 positions (94.7%), than at sn‐1 position (66.0%). Practical Application: The information of stereospecific positional distribution of fatty acids in the camellia oil can be used for the development of the structured lipids for food, pharmaceutical, and medical purposes.  相似文献   

13.
The changes in the fatty acids of frog leg meat during frozen storage were studied with column and gas-liquid chromatography. The major component of the lipids, the phospholipids constituted 90% of total lipids. 16:0, 18:0, 22:0 and 18:2 polyunsaturated fatty acid were the major fatty acids of the frog legs meat lipids. Short chain fatty acids were noticed to the extent of 10%. During frozen storage the proportion of phospholipids decreased, while that of neutral lipids increased. Since the total lipid content was constant, phospholipases were presumably responsible for this change. Alterations in the fatty acid composition of the neutral lipids during storage were consistent with such a hypothesis.  相似文献   

14.
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   

15.
Lipids from papayas (Carica papaya L.) Solo cultivar at various stages of ripeness were extracted and fractionated into neutral lipids (NL), glycolipids (GL), and phospholipids (FL). The major fatty acids of the three lipid classes at all levels of ripeness were C16:0, C18:1, C18:2, C18:3. NL increased in unsaturation with maturity as indicated in the decrease of the various saturated/unsaturated fatty acid ratios, GL decreased in the ratio of C16:0/C16:1 due to an increase in C16:1 fatty acid with increasing fruit maturity. The remaining fatty acids in GL remained relatively unchanged. The phospholipid fraction increased in unsaturation with maturity due to increases in C16:1 and C18:3 fatty acids.  相似文献   

16.
An examination was made of the fatty acid and phospholipid composition of longissimus dorsi muscle from Pietrain and Large White pigs. The neutral lipid fraction from Pietrain muscle had a more unsaturated fatty acid composition possibly because of a reduced rate of intramuscular fat deposition in these pigs. The phospholipid content of muscle and muscle sarcoplasmic reticulum was similar in both breeds. The fatty acid composition of phospholipid and the concentrations of individual phospholipids were also similar. Differences in the lipid composition of muscle between the breeds appear to reflect a reduced capacity for carcass fat deposition in Pietrains rather than the propensity of pigs of this breed to produce muscle which is pale, soft and exudative (p.s.e.).  相似文献   

17.
The identity, composition and concentration of each of the major lipids found in Alocasia tubers were investigated using a combination of chromatographic procedures. On a weight to weight basis, the neutral lipids, glycolipids and phospholipids comprised 60.5, 19.0 and 20.5% respectively while the total extractable lipids accounted for 0.6% of the dry weight. In addition to the conventional lipid classes of tubers, the presence of tri- and tetragalactosyl diglycerides was confirmed. The predominant fatty acid in each lipid class was linoleic acid with palmitic, oleic and linolenic acids being the other ones. In general, a high degree of unsaturation (66%), similar for most tuber lipids, was established for the component fatty acids of Alocasia.  相似文献   

18.
LIPIDS OF CURED CENTENNIAL SWEET POTATOES   总被引:1,自引:0,他引:1  
SUMMARY –Lipids isolated from cured Centennial sweet potatoes were identified and quantitated by a combination of column and thin layer chromatography. These lipids were shown to consist of 42.1% neutral lipids, 30.8% glycolipids and 27.1% phospholipids. Triglycerides and steryl esters were the major lipids of the neutral fraction. Among the phospholipids, phosphatidyl ethanolamine, phosphatidyl choline and phosphatidyl inositol were the most abundant. Galactolipids and the steryl glucosides were also present. The predominant fatty acids were stearic, palmitic, oleic, linoleic and linolenic.  相似文献   

19.
The effects of produced ethanol and specific growth rate on the lipid content and composition of Saccharomyces cerevisiae CBS 2806 were studied using anaerobic chemostat cultures. The cells adapted to increased concentrations of produced ethanol by increasing the proportion of ergosterol at the expense of lanosterol, by increasing the proportion of phosphatidylinositol at the expense of phosphatidylcholine, and by increasing the amount of C18:0 fatty acids in total phospholipids at the expense of C16:0 fatty acids. The produced ethanol had no effect on the phospholipid content nor on the proportion of unsaturated fatty acids in the phospholipids. The specific growth rate had no effect on the phospholipid content, the sterol composition, the phospholipid composition, the fatty acid composition of total phospholipids, or on the proportion of unsaturated fatty acids in the phospholipids of S. cerevisiae. It was not possible to separate the effects of produced ethanol and growth rate on the ergosterol content of the chemostat-grown S. cerevisiae cells.  相似文献   

20.
Squid (Loligo vulgaris) was found to contain 25 g kg?1 lipids of which approximately 75% were phospholipids. The phospholipids were shown to consist of phosphatidylcholine (56% of total phospholipids), phosphatidylethanolamine (29%), phosphatidylserine (2%), phosphatidylinositol (2%). sphingomyelin (5%), lyso-phosphatidylcholine(3%) and the unusual lipid ceramide aminoethylphosphonic acid (3%). The major saturated fatty acid in both phospholipids and non-phosphorylated lipid was C16:0 (26% and 21%, respectively, of total fatty acids), while the major unsaturated fatty acid in both lipid fractions was C22:6n-3 (34% and 23%, respectively) followed by C20:5n-3 (14% in both lipids).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号