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1.
The total lipids in field pea seeds and refined starch were extracted by five aqueous/organic solvent systems and the greatest yield of total. neutral and polar lipids was obtained with hot n-propanol-water (3:1 v/v). Lipids extracted from field pea seeds represented 2.9% of the seed weight and consisted of 43.2% neutral lipids, 3.2% glycolipids and 53.6% phospholipids. The major components of the three fractions were 70% triacylglycerol in neutral lipid, 28% esterified sterol glycoside in glycolipid and 55% phosphatidylcholine in phospholipid. The purified starch fraction contained 0.22% surface lipids and 0.09% internal lipids. The surface lipids were primarily sterol esters and free fatty acids while only free fatty acids were found in the internal lipids. The ability of lysophospholipids and fatty acids to complex with field pea starch was demonstrated by differential scanning calorimetry and X-ray diffraction, respectively.  相似文献   

2.
Wheat flour non-starch lipids (lipids not bound to starch) were quantitatively extracted with water-saturated n-butanol (WSB), benzene-ethanol-water (10:10:1, by vol.) or ethanol-diethyl ether-water (2:2:1, by vol.) in 10min at 20 °C. Starch lipids (lipids bound to starch) were subsequently extracted with WSB at 90–100 °C. Carotenoid pigments were quantitatively extracted with the non-starch lipids. There was no significant hydrolysis of esterified fatty acids and no detectable autoxidation of unsaturated acids in the hot solvent extracts. Non-starch and starch lipids from a high grade spring wheat flour and three grades of winter wheat flour were separated by thin-layer chromatography and quantified as fatty acid methyl esters (FAME) by gas-liquid chromatography (g.l.c.) using heptadecanoic acid (or its methyl ester) as internal standard. Total flour and starch lipids after acid hydrolysis were also converted to FAME for quantitation by g.l.c. Non-starch lipids consisted of 59–63% non-polar (neutral) lipids, 22–27% polar glycolipids and 13–16% phospholipids. Steryl esters, triglycerides, and all the diacyl galactosylglycerides and phosphoglycerides were present only in non-starch lipids. Starch lipids consisted of 6–9% non-polar (neutral) lipids (mostly free fatty acids), 3–5 % polar glycolipids and 86–91 % phospholipids (mostly lysophosphatidyl choline). Starch lipids were almost exclusively monoacyl lipids. Factors are given for converting weight of FAME into weight of original lipid for all individual lipid classes in wheat which contain O-acyl groups. Factors for total lipids are: total starch lipids = FAME × 1.70, total non-starch lipids = FAME × 1.20, and total flour (non-starch + starch) lipids = FAME × 1.32. Similar factors could be used to convert weight of lipids obtained by conventional acid hydrolysis methods into weight of unhydrolysed lipids. Phospholipid contents are given by: total starch phospholipids = P × 16.51, total non-starch phospholipids = P × 23.90, total flour phospholipids = P × 17.91.  相似文献   

3.
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   

4.
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   

5.
The changes in lipid composition and fatty acid distribution of sauerkraut during fermentation, canning, processing and storage were investigated organoleptically and chemically. Treatments were significant throughout the experiment. pH, lactic acid, and moisture content did not reveal any substantial changes. Total lipids, neutral lipids, and glycolipids increased, whereas phospholipids were unaltered during fermentation and processing. Quantitative changes in nonpolar and polar lipids during storage were in opposite directions, and net lipid content did not change. The changes in fatty acid composition were primarily in the distribution of palmitic, stearic, oleic, linoleic and linolenic acids during fermentation, processing and storage. Total lipids did not relate to organoleptic evaluation. However, polar lipids, specifically phospholipids, were directly related to storage stability and increased amounts of general acceptability. The formation of phospholipids may be catalysed by a reaction between tin from the cans and polar lipids at the expense of neutral lipids.  相似文献   

6.
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 (lambda max at 410 nm). 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 proteins isolates were observed.  相似文献   

7.
The fine granule starch fraction of a commercially milled, bleached, wheat flour was richer in nitrogen, extractable lipid, and polar lipids (glycolipids and phospholipids) compared with the coarse granule starch, which was richer in triglycerides and its hydrolysis products. The intermediate size starch fraction fell between fine and coarse starch in the level of these components while the “pentosan” fraction was very high in lipid and nitrogen, although it was of similar phosphorus content to the starch fractions. The total fatty acid content of the fine starch was over 50% higher than that of the coarse starch and both results were higher than the extractable lipid contents of the respective fractions. The results are explained in terms of higher protein and phospholipid content of the fine starch, which may be related to its higher specific surface area.  相似文献   

8.
Cabbage (Brassica oleracea L, var Glory) is one of the cruciferous vegetables. The objective of this study was to investigate the neutral, glyco- and phospholipids of cabbage and their fatty acid composition. Lipids from its leaves were extracted and fractionated into neutral lipids, glycolipids and phospholipids. The fatty acids of each fraction were analysed by gas liquid chromatography.  相似文献   

9.
In lipids of salted sea urchin gonads, the changes in contents of neutral lipids (NL), glycolipids (GL) and phospholipids (PL), in peroxide and carbonyl values, in lipid class compositions of NL and PL, and in fatty acid composition were investigated as a function of storage time. NL increased while GL and PL decreased by autolysis during 180 days storage. The increase of NL resulted from free fatty acids (FFA) [plus fatty acid ethyl esters (FAEE)] generated enzymatically by hydrolysis of PL and GL. Triglycerides were stable throughout a period of storage. In heat-treated and salted gonads, NL, GL and PL remained nearly unchanged during storage, and FFA and FAEE could not be detected. The oxidation of lipids was not detected during 180 days storage, although salted gonads had high content of polyunsaturated fatty acids.  相似文献   

10.
Lipids were freshly extracted from earthworms from agricultural pasture land, and fatty acid compositiona analyses were carried out on the total lipids; phospholipids; triglycerides; free fatty acids; mixed sterol esters, wax esters, free methyl esters, etc.; glycolipids; and neutrallipids. A wide variety of fatty acids ranging from C10 to C32 were identified. In the fatty acids of the total lipids, polyunsaturated constituents predominated in amount, while monomethyl branched, isoprenoid and n-odd-numbered acids were present in appreciable proportions. Eicosa-5,8,11,14,17-pentaenoic acid and arachidonic acid occurred at higher levels than any other components and were located mostly in the phospholipids. Significant contents of linoleic and linolenic acids were also detected. Earthworms collected in spring had a fatty acid composition which differed noticeably from that of worms from other seasons. The content of lauric acid during spring was much higher than that normally found in animals or pasture plants. The composition of the free fatty acids indicated that these components were the products of lipolysis and were derived from all the lipid classes. The results of this investigation suggest that the diet of local earthworms, which is reported to consist mainly of dead plant material, is supplemented by living and dead microorganisms from ingested soil.  相似文献   

11.
S. Ito  S. Sato  Y. Fujino 《Starch - St?rke》1979,31(7):217-221
The starch of a Japanese rice variety contained 0,69% of internal lipid. The ratio of neutral lipid, glycolipid and phospholipid in the total lipid was 37.0: 20.3: 42.7. The principal components of the neutral lipid were free fatty acid and monoglyceride; those of glycolipid were monoglycosylmonoglyceride and diglycosylmonoglyceride; those of phospholipid were lysophosphatidylcholine and lysophosphatidylethanolamine. All were monoacyl lipids, and they constituted more than 90% of the total internal starch lipids. The predominant fatty acid components were palmitic acid and linoleic acid. The component sugars of glycolipids were galactose and glucose, galactose being predominant. Lysophosphatidylcholine and monoglyceride were almost of the α-type.  相似文献   

12.
为研究海水鱼和淡水鱼鱼头磷脂及脂质脂肪酸组成的差异,以海水鱼(马鲛鱼、巴浪鱼、金鲳鱼)和淡水鱼(罗非鱼、鲫鱼、鲢鱼)鱼头为研究对象,利用Floch法提取6种鱼鱼头总脂;硅胶柱层析法将总脂分离收集中性脂、糖脂和磷脂;薄层层析(thin layer chromatography,TLC)分析比较6种鱼鱼头磷脂种类的分布、组成;气相色谱(Gas chromatography,GC)分析6种鱼鱼头脂质的脂肪酸组成。结果表明,6种鱼鱼头中提取率最高的脂质类型为中性脂,占总脂的48.98%~77.84%,其次为磷脂,占总脂的5.93%~22.86%,糖脂提取率最低,占总脂的3.67%~15.91%。鱼头磷脂中共检出4种磷脂组分,分别为磷脂酰乙醇胺(Phosphatidylethanolamine,PE)、磷脂酰胆碱(Phosphatidylcholine,PC)、鞘磷脂(Sphingomyelin,SM)、溶血磷脂酰胆碱(Lysophosphatidylcholine,LPC),其中PC明显高于其他磷脂组分。脂质中均含有较高含量的多不饱和脂肪酸(Poly-unsaturated fatty acid,PUFA),其中以二十二碳六烯酸(docosahexaenoic acid,DHA)为主,且均含有二十碳五烯酸(eicosapntemacnioc acid,EPA),海水鱼和淡水鱼鱼头磷脂中DHA和EPA占总脂肪酸的比例最高,分别为18.39%~21.43%和5.61%~10.38%,且海水鱼鱼头中以DHA和EPA为主的PUFA含量高于淡水鱼鱼头。因此,海水鱼鱼头是提取n-3多不饱和脂肪酸的潜在资源,尤其是制备n-3多不饱和脂肪酸型磷脂的良好来源。  相似文献   

13.
Yang H  Ma C  Qiao F  Song Y  Du M 《Meat science》2005,71(4):670-675
Lipolysis in intramuscular lipids during the processing of Chinese Xuanwei ham has been studied by analyzing the changes of glycerides, phospholipids and free fatty acids in biceps femoris muscle. Results showed that the glycerides accounted for 73.2% of total lipid content in fresh ham, the phospholipids represented 25.3% and the free fatty acids 2.3% of the total lipid content, respectively. A rapid lipolysis of phospholipids occurred during the first 4 months of processing and slowed down during the rest period. A preferential hydrolysis for palmitic, linoleic and arachidonic acids in phospholipid fraction was observed. Glycerides only changed a little throughout the process, while an increase of free fatty acids during processing was observed. The results suggest that phospholipids are the main substrate of lipolysis in the intramuscular lipids of Chinese Xuanwei ham.  相似文献   

14.
The defatting of both corn and wheat starch with 85% methanol yields starches which start to gelatinise at lower temperatures and have increased overall viscosities compared with untreated starches. The lipids extracted from wheat and corn starch with 85 % methanol were similar in total amount but showed very large differences in the proportions of neutral and phospholipids. The extracted corn lipids contained eight times as much neutral lipids (mainly free fatty acids) as phospholipids whereas the proportions of neutral and phospholipids in wheat starch were approximately equal. Addition of extracted lipids to defatted starches significantly modified the swelling and viscosity characteristics. Addition of wheat and corn lipids to potato starch (which contains almost no lipids) indicated that the higher percentage of phospholipids in wheat starch probably contributed towards the lower viscosity characteristics of wheat starch compared with corn starch.  相似文献   

15.
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   

16.
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   

17.
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   

18.
High solids cabbage lipids were investigated. Crude lipids were extracted and separated by column chromatography into neutral lipids, glycolipids and phospholipids. Fatty acids were analyzed by gas-liquid chromatography. Consistent with other plant lipid patterns, palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids constituted the major fatty acids. High solids cabbage cultivars were 1.8–2.0% higher in dry matter than the standard cultivars.  相似文献   

19.
探讨热风干燥过程中青鱼片油脂的变化情况。在青鱼片的不同干燥阶段提取油脂,检测油脂氧化程度,油脂成分及脂肪酸组成的含量变化。在干燥过程中鱼片油脂的过氧化值、羰基价和酸价显著性升高(P<0.05)。随着甘油三酯和磷脂含量的下降,游离脂肪酸含量明显增加,表明在干制过程中油脂在酯酶和磷酸化酶的催化下发生了水解反应。在总油脂和总磷脂中多不饱和脂肪酸,尤其是二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)含量下降。在游离脂肪酸中,除DHA以外的多不饱和脂肪酸含量均显著升高。研究结果表明,青鱼片热风干燥过程中其油脂被氧化,同时发生脂质降解,特别是不饱和脂肪酸被释放为游离态。  相似文献   

20.
Lipid fractions and starch- and protein-lipid binding of single and blended oat, rye, buckwheat and wheat flour, dough and bread matrices were investigated, and results correlated with the functional and nutritional properties of the grain matrices during mixing and baking. Non-starch lipid was the most prominent fraction in terms of absolute content and as a percentage of total lipids. Free lipids, starch lipids and bound lipids were, respectively, the major, intermediate and minor lipid fractions in flours, doughs and breads. Great differences in total lipid content due to sampling result in divergences amongst lipid fraction content and distribution, especially for starch and bound lipid fractions. Lipids bound to proteins during dough mixing are translocated and bound to starch during baking. In blended samples, the higher fibre content seems to provoke a reduction of the lipid–protein and lipid–starch linkages due to interactions between fibres and endogenous biopolymers. Starch lipid showed the most significant correlations with parameters related to dough and bread performance during breadmaking, especially over the mixing step. Valuable fresh bread functional characteristics, such as high specific volume and high sensory score for softness and overall acceptability, correspond to a starch lipid’s increase due to mixing. The higher the free and starch lipids decrease by reason of temperature treatment—baking—the larger the starch hydrolysis and the higher β-glucans and total dietary fibre contents.  相似文献   

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