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1.
Pharmacology of Skin Surface Lipids Influence of drugs on the amount and composition of lipids of skin, scalp and hair is reviewed. Drugs can influence the amount of lipids, the liberation of free fatty acids from triglycerides and the ratio of sebaceous gland lipids and epidermal lipids. A reduction in the content of free fatty acids and the amount of lipids is indicative of a favorable influence on Acne vulgaris and Seborrhoea oleosa capitis. A reduction in the amount of epidermal lipids indicates favorable influence on dandruff. A number of drugs show undesirable side effects with respect to the amount and composition of lipids.  相似文献   

2.
The chemical composition of bitter almond, plum and mango kernels and the physico-chemical characteristics of their lipids were studied. Bitter almond and plum kernels contained higher amounts of lipids in comparison to mango kernels. All kernel lipids were found free from hydrocyanic acid. The predominant lipid class of the studied kernel lipids was triglycerides. Oleic acid was the major fatty acid present in bitter almond and plum kernel lipids, while mango kernel lipids were rich in stearic and oleic acid.  相似文献   

3.
Photoswitchable lipids are emerging tools for the precise manipulation and study of lipid function. They can modulate many aspects of membrane biophysics, including permeability, fluidity, lipid mobility and domain formation. They are also very useful in lipid physiology and enable optical control of a wide array of lipid receptors, such as ion channels, G protein-coupled receptors, nuclear hormone receptors, and enzymes that translocate to membranes. Enzymes involved in lipid metabolism often process them in a light-dependent fashion. Photoswitchable lipids complement other functionalized lipids widely used in lipid chemical biology, including isotope-labeled lipids (lipidomics), fluorescent lipids (imaging), bifunctional lipids (lipid–protein crosslinking), photocaged lipids (photopharmacology), and other labeled variants.  相似文献   

4.
Gluten lipids are of two kinds, polar and nonpolar. Both groups consist of a large number of lipids. Gluten lipids can be extracted by conventional solvents as ethanol but also by supercritical carbon dioxide. The high density and the good mass transport properties make the supercritical fluid an excellent solvent. Ethanol extracted gluten lipids have been fractionated with supercritical CO2 at different pressures and constant temperature. The extract contains triglycerides and free fatty acids, and a more concentrated fraction of polar lipids is left in the extraction vessel. While both polar and nonpolar lipids are soluble in ethanol, only nonpolar lipids are dissolved by supercritical CO2. An addition of a small amount of ethanol to the CO2, can, however, increase the solubility of the polar lipids.  相似文献   

5.
Cholesterol has been detected as one of the major sterols in the surface lipids of higher plant leaves. It was widely distributed among the plant leaves of various species as a common main sterol component with a few exceptions. The content of cholesterol amounted to 71.5% of the total sterols in the surface lipids of rape leaves. However, the proportion of cholesterol in the intracellular lipids of rape leaves was lower than that in the surface lipids, and the seed lipids contained only a trace amount of cholesterol, as reported in the literature. In the leaf surface lipids examined, a minor amount of cholestanol associated with cholesterol often was detected by capillary gas chromatography and gas chromatography-mass spectrometry. The related analysis for the surface lipids of fruits showed that cholesterol was one of the major component sterols also in those lipids of several species.  相似文献   

6.
The relative per cents of polar and neutral lipids and the fatty acid profile of the polar and neutral lipids of nine thermophilic and nine mesophilic fungi were examined and compared. The polar lipids of the thermophiles contained an average of 0.89 double bonds per mole fatty acid (unsaturation index, USI) and were considerably more saturated than the corresponding lipids of the mesophiles (average 1.32 USI). Within the thermophilic species the polar lipids were generally more saturated than the neutral lipids (average 0.95 USI) and in the mesophilic species the polar lipids were usually more saturated than the neutral lipids (average 1.14 USI). The mesophiles produced higher levels of 16∶1, 18∶2 and 18∶3 fatty acids than the thermophiles and preferentially incorporated 16∶1 and 16∶2 into their polar lipids. The thermophiles produce higher levels of saturated fatty acids and 18∶1 than the mesophiles and preferentially incorporated the saturated fatty acids into their polar lipids.  相似文献   

7.
A few species ofFusarium have been evaluated for their potential to produce lipids. The isolates under investigation exhibited wide variation with respect to the mycelial weight, total lipid content and percentage composition of polar and nonpolar lipids in which triglycerides were the major components (81–90%). Palmitic, stearic, oleic and linoleic acids were the major fatty acids in both the fractions. The polar lipids contained higher levels of linoleic acid, whereas nonpolar lipids contained oleic acid as the predominant acid. Nonpolar lipids were more saturated than polar lipids.  相似文献   

8.
The residual lipids of rapeseed meals produced by pilot-scale and commercial solvent-extraction processes were extracted with hexane (free lipids), then extracted with chloroform-methanol (bound lipids). Thin layer chromatography showed that the free lipids were similar to those previously reported for intact mature seed. The amount of residual free lipid varied with the method of meal production. Bound lipids were similar for all methods of production but differed in some respects from polar lipids of mature seed. Issued as Paper No. 142 of the Food Research Institute, Canada Department of Agriculture, Ottawa, Canada.  相似文献   

9.
The utilization of lipids is presently in the spotlight of food industry as they are one of novel renewable and sustainable raw materials. Lipids derived materials are considered as a promising alternate to petro-based polymers as they are sustainable, biorenewable, biodegradable, and environmentally benign. These unique attributes draw the attention of scientific community for the use of lipids in food packaging applications with a potential to compete with fossil fuel derived polymers. This paper reviews recent advances in the use of lipids and their effect on the barrier, antimicrobial, antioxidant, and mechanical properties of films, coating and nanocomposites for food packaging applications. Modification of lipids and its chemical interactions with other biopolymers during processing for the synthesis of different materials are also discussed. Global patents and research trend in use of lipids for the preparation of biocomposites are also described. The role of lipids in the circular economy is highlighted and life cycle assessment of lipids derived products is outlined with examples. The review is concluded with synoptic view of existing and forthcoming potential use of lipids in various food packaging applications.  相似文献   

10.
Lipids were extracted with petroleum ether and with water-saturated n-butanol from 8 hard red winter, 5 hard red spring, and one each from soft red, durum, and club wheat varieties from 2 harvests. The butanol-extracted lipids were fractionated into nonpolar and polar lipids by silicic acid column chromatography, and the two major fractions were subfractionated by thin-layer chromatography. Durum wheats contained the highest lipid contents, and the highest concentration of nonpolar lipids. The breadmaking wheat varieties had a lipid content which was consistent for the 2 years examined. The total and nonpolar lipid contents of hard red spring wheats were higher than of hard red winter wheats. The polar lipid contents of wheats from the two classes were essentially equal. Total lipid contents were substantially higher in wheats than in flours milled from the wheats. Nonpolar lipids constituted about one-half of the flour lipids and two-thirds of the wheat lipids. Concentrations of triglycerides were higher in wheat than in flour nonpolar lipids. Glycolipids were present in comparable concentrations in wheat and in flour polar lipids; concentration in polar lipids of phosphatidyl choline was higher and of other phospholipids was lower in wheat than in flour polar lipids. No. 547, Kansas Agrieultural Experiment Station, Manhattan. Done in part under contract with the U.S. Department of Agriculture and authorized by the Research and Marketing Act of 1946. Supervised by the Western Utilization Research and Development Div., ARS.  相似文献   

11.
A novel three-directional thin layer chromatography (TLC) method is reported by which all the polar and neutral lipids are isolated on a single TLC plate. Following resolution of the phospholipids by two-directional TLC, lipids are visualized by ultraviolet light after spraying with 2′,7′-dichloro-fluorescein. A line is drawn across the plate, parallel to the second direction of development, separating the resolved phospholipids and the neutral lipids concentrated along the solvent front. The TLC plate is then chromatographed in the reverse direction of the second development to resolve the neutral lipids. By exposing the lipids to HCl fumes after the first development, the plasmalogen content of the lipids may also be determined. This new technique is rapid and lends itself to qualitative and quantitative analyses of total lipids. Contribution no. 1163 from the Animal Research Centre.  相似文献   

12.
Petroleum ether (PE) extracted 1.00% total free lipids (0.70% nonpolar and 0.30% polar) and 2-propanol (PrOH) extracted 1.36% total free and bound lipids (0.73% nonpolar and 0.63% polar) from wheat flour; the lipid fractions were characterized by thin layer chromatography. PE- or PrOH-defatted flours were baked after reconstitution with total, nonpolar, or polar wheat flour lipids; or with equivalent amounts of nonionic sucrose monopalmitate (SMP), ethoxylated monoglycerides (EMG) — each with a hydrophile-lipophile balance (HLB) of 14.0 or anionic sodium stearoyl-2-lactylate (SSL) — with an HLB value of 9.0. Defatted flours supplemented with surfactants alone or in combination with wheat flour lipids were used in bread with no-shortening and with 3%-shortening. The importance of the polar flour lipids in breadmaking was verified. The lipids in wheat flour were essential for maximizing the beneficial effects of shortening on breadmaking quality. Nonionic SMP or EMG completely replaced both PE-extractable wheat flour free total lipids ( or their non-polar or polar fractions) and 3% shortening; nonionic surfactants with high HLB were better than the anionic SSL for replacing free flour lipids. No surfactant completely replaced unfractionated PrOH-extracted lipids (free + bound) and shortening or total polar flour lipids (free + bound). All surfactants, especially anionic SSL, added with PrOH-extracted polar lipids improved the overall bread-making properties of the PrOH-defatted flour both in the absence and in the presence of shortening. Presented at the AOCS Meeting, New York, May 1977  相似文献   

13.
Skin Lipids, a Group of Unusual Lipids in Man and Animals Skin lipids in man and animals show significant structural differences in comparison to other organ lipids, which is documented by the unusual positions of double bonds and the degree of substitution of the fatty acids. This is demonstrated for human skin and birds uropygial gland lipids as example. The structures of these lipids are supposed to correlate with certain functions. Bacteriostatic and fungistatic functions, individual odoration profile, and lipids as excretion vehicles for fat-soluble substances are discussed.  相似文献   

14.
Mature kernels of an inbred corn were hand dissected into germ and endosperm fractions. Among various solvents tested, boiling, water-saturatedn-butanol extracted the most lipid from endosperm, and it was used as t h e extracting solvent for both germ and endosperm. The germ contained 78% of the total lipids and the endosperm 17%. The most striking differences in the fatty acid compositions of the triglycerides and polar lipids were higher levels of stearic and linolenic acids in the endosperm lipids. Although precautions were taken during extraction to inactivate lipases, immediately after harvest the free fatty acid level of the total lipids of the whole kernel was 6.5%. Ninety-five percent of the free fatty acids was in the endosperm fraction where the free fatty acids made up 36.5% of the total lipids. In germ, free fatty acids represented only 0.6% of the total lipids. The individual phospholipid and glycolipid classes of the endosperm and germ lipids were similar except for high levels of lyso compounds in the endosperm lipids. The higher levels of linolenic acid, free fatty acids and lyso lipids in endosperm may affect the keeping quality of the corn grain and of fractions milled from the endosperm. Presented at the AOCS meeting, St. Louis, May 1978.  相似文献   

15.
Large amounts of utilizable by-products are produced concomitant with silver carp processing. The lipids from fish brain contain considerable essential fatty acids which however have seldom been studied. In this study, the lipids extracted from the brain of silver carp exhibited good physicochemical properties. Forty volatile compounds were identified, of which hydrocarbons and aromatics predominated. The ratios of polar lipids and phospholipids to total lipids were 22.73 and 10.95 % respectively. Phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS) accounted for 83.9 % of the phospholipids. Major fatty acids of neutral lipids, polar lipids, PC, PE and PS differed significantly. PE had the most polyunsaturated fatty acids (PUFA), while PC, PE and PS were rich in docosahexaenoic and eicosapentaenoic acids. Moreover, the ratios of fatty acids were considered to be reasonable due to high levels of n3 PUFA. The lipids from silver carp brain have been demonstrated to be healthy and nutritious. The results herein confirm that silver carp brain lipids are a commercially and industrially feasible prospect.  相似文献   

16.
Cuticular lipids cover nearly all parts of insect and are the chief agent for restricting water loss. The structure of insect epicuticles is reviewed, with emphasis on the role of cuticular lipids and the metabolism of cuticular lipids. The chemical composition of insect cuticular lipids are discussed with particular emphasis on the types in which hydrocarbons, was esters and fatty alcohols predominate. What little evidence is available on the biosynthesis of insect cuticular lipids is discussed. One of six papers to be published from the Symposium on Natural Waxes, presented at the AOCS Meeting, San Francisco, April 1969.  相似文献   

17.
Listeria monocytogenes is a Gram-positive bacterium that can adapt to high salinity and cold. Because the membrane lipids may play a role in its survival and adaptation, we have examined the polar lipids ofL. monocytogenes. Extraction of total lipids fromL. monocytogenes yielded 7±1 mg/mL wet cells. Polar lipids represented 64% of total lipids and contained 9% lipid-phosphorus. Polar lipids were separated into 14 components by two-dimensional thin-layer chromatography. Eight components (88% of polar lipids) contained lipid-phosphorus; among these was one major component (34% of polar lipids). Two other phospholipids were ninhydrin-positive components and accounted for 15% of the polar lipids. Orcinol staining revealed two glyco- or sulfo-lipids accounting for 9% of polar lipids. Five components (4% of polar lipids) were amino components free of phosphorus. The major component contained 46% of its fatty acids as 15:0anteiso, 24% as 17:0anteiso, and 11% as 15:0iso. The fatty acid profile of the remaining polar lipids was variable, consisting primarily of 16:0, 18:0, 15:0anteiso, and 17:0anteiso. Their unsaturation level was ≤20%; however, the major phosphoaminolipid component was 46% unsaturated. The ratios of 15:0anteiso/17:0anteiso and 15:0anteiso/15:0iso were similar in all classes, averaging 1.5 and 4.5, respectively. Since the adaptation process to stressful environments involves activation of a membrane transport system for the protectant glycine betaine, the membrane lipids may play a role in enabling transport.  相似文献   

18.
In edible parts and seeds of 15 vegetables, belonging to the families of Brassicaceae, Apiaceae and Asteraceae, the fatty acid composition of total lipids was determined. Among the vegetables used in Middle Europe plants of the Brassicaceae family predominate. Whereas their seed oils are rich in erucic acid, this acid is absent in the lipids of edible vegetative organs (leaves, flowers, sprouts, tubes). The lipids of these organs were found to be rich in linolenic acid and containing more cis-vaccenic acid than oleic acid. In plants, belonging to Apiaceae family, petroselinic acid was observed solely in seed oils and not in vegetable lipids. These lipids were high in linoleic acid and had more oleic than cis-vaccenic acid. 7,10,13-Hexadecatrienoic acid was found in all lipids rich in linolenic acid.  相似文献   

19.
Significant progress has been made in the construction of laboratory models of protocells. Most frequently the developed vesicle systems utilize single-chain lipids rather than the double-chain lipids typically found in biological membranes. Although single-chain lipids yield less robust vesicles, their dynamic characteristics are highly exploitable for protocellular functions. Herein the advantages of using single-chain lipids in the construction of protocells are discussed.  相似文献   

20.
超临界CO_2萃取被孢霉菌体油脂及花生四烯酸的研究   总被引:5,自引:0,他引:5  
采用超临界CO2 萃取技术提取被孢霉菌体油脂 ,研究在超临界状态下 ,温度、压力、夹带剂与时间对油脂萃取率的影响 ,并分析对油脂成分的影响 ,从实际结果确定的优惠工艺条件为 :萃取压力为 13MPa ,萃取温度为 32℃ ,时间为 70min ,甲醇 10 %。此时油脂得率达到 37 4 5 % ,花生四烯酸含量达到 15 6 8%。  相似文献   

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