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1.
The individual molecular species composition of diacyl, alkylacyl and alkenylacyl glycerophospholipids was determined in mouse
peritoneal macrophages. A marked deterogeneity in the relative composition (mol%) of macrophage ether and ester phospholipid
individual species was noted. High concentrations of 16∶0–20∶4 were found in ether phospholipids such as alkenylacyl glycerophosphoethanolamine
(GPE; 27.5 mol%) and alkylacyl glycerophosphocholine (GPC; 16.6%) as compared to mol % levels of 16∶0–20∶4 in diacyl GPE (5.7%)
and diacyl GPC (8.1%), respectively. Interestingly, alkenylacyl GPE was highly enriched in 1-ether (16∶0) relative to alkylacyl
GPC. The predominant diacyl molecular species in glycerophosphoinositol (GPI) and glycerophosphoserine (GPS) were 18∶0–20∶4
(59.1%) and 16∶0–18∶1 (41.1%), respectively. It is noteworthy that the level of 18∶0–20∶4 was several times higher in diacyl
GPI (59.1%) than in diacyl GPS (11.1%), diacyl GPE (25.7%), and diacyl GPC (3.7%). The most abundant molecular species in
diacyl GPC and diacyl GPE were 16∶0–18∶1 (29.9%) and 18∶0–20∶4 (25.7%), respectively. The abundance of 20∶4 in ether phospholipids,
specifically 16∶0–20∶4 and 18∶0–20∶4, in alkylacyl GPC is significant in view of the role these antecedents play in the biosynthesis
of platelet-activating factor (PAF) and 20∶4-derived eicosanoids in stimulated macrophages. The unique molecular species composition
of the peritoneal macrophage distinguishes this cell type from others. 相似文献
2.
David I. Wilkinson 《Lipids》1970,5(1):148-149
The occurrence of the various positional isomers of monounsaturated fatty acids of mouse skin surface lipids was studied by
conventional oxidative cleavage-gas liquid chromatography techniques. The pattern observed could be accommodated by the biosynthetic
scheme proposed elsewhere for rat skin fatty acids, except that 18∶Δ9 replaced 16∶Δ9 as the main precursor. 相似文献
3.
Three groups of diesters have been isolated and identified in the lipids of steer meibomian glands. The first group, designated
as α Type I, with the abbreviated formula FA-αOHFA-FA1c, consisted of α-hydroxy fatty acids esterified to fatty acids and
fatty alcohols in the approximate molar ratio 1∶1∶1. The second group, designated as ω Type I-St, with the abbreviated formula
FA-ωOHF A-St, consisted of ω-hydroxy fatty acids esterified to fatty acids and sterols in the approximate molar ratio 1∶1∶1.
The third group, designated as α,ω Type II, with the abbreviated formula FA-α,ωdiol-FA, consisted of α,ω-diols esterified
to 2 moles of fatty acids. The sum of the different diesters comprised about 9% of total steer meibomian lipids.
Capillary GLC of the fatty acids of αType I diesters showed the fatty acids to be a family with a two-cluster profile, one
at C12 to C20 and the other at C21 to C31, with anteiso chains predominating. Fatty acids from ωType I-St and α,ωType II diesters gave mainly a one-cluster profile
in the short long chain, C23 to C30, with anteiso chains predominating, while the α-hydroxy fatty acids were short chain C13 to C18 acids with C16 predominating. The sterols in diesters ωType I-St were cholesterol (∼60%), Δ7 cholestenol (∼35%) and an unidentified compound
(∼5%) with a GLC retention time slightly longer than Δ7 cholestenol on SE-30 phase. The ω-hydroxy fatty acids and α,ω-diols
both were of exceedingly long chain lengths, C29−C38, and showed similar GLC profiles. Two types of triesters comprising approximately 1% of total steer meibomian lipids have
been isolated but incompletely characterized. In terms of molar ratios, one group of triesters gave fatty acids:ω-hydroxy
fatty acids:α-hydroxy fatty acids:sterols + fatty alcohols as approximately 1∶1∶1∶1. The other contained fatty acids, α-hydroxy
fatty acids and α,ω-diols in what appears to be a complex mixture of several triesters. Diesters ωType I and α,ωType II also
were found in human meibum. Hitherto these two diesters have not been found in any animal tissue. 相似文献
4.
Hirosuke Oku Jyutaro Shudo Kunio Mimura Akinori Haratake Junichi Nagata Isao Chinen 《Lipids》1995,30(2):169-172
A neutral lipid class was isolated by thin-layer chromatography from the skin surface lipids of the hairless mouse. The fraction
migrated faster than triglycerides and had a migration rate similar to that of diacyl alkanediols (diester wax). Upon deacylation,
however, the long-chain diols were identified as 1-alkylglycerol ethers based on their chromatographic properties and on the
mass spectra of their nicotinylidene derivatives. Thus, the skin lipid fraction was identified as 1-O-alkyl-diacylglycerol. The alkyl moieties were all saturated and even-numbered and ranged in chainlength from C16 to C22 with 1-O-hexadecylglycerol amounting to 34% of the total glycerol ether moieties. The fatty acids derived from this lipid fraction
were mostly monoenoic with chainlengths ranging from C16 to C24. The major acyl component was eicosenoic acid (20∶1) representing 61% of the total fatty acids. 相似文献
5.
Natural bitumen (viscous, viscoplastic, and solid) cannot be extracted by methods commonly used in oil production, and it is usually a disregarded reserve of hydrocarbon resources. A sharp difference between the properties of Permian bitumens from the Ural-Volga Region and Carboniferous and Devonian oils in the fields of Tatarstan was demonstrated. This difference is caused by the predominance of asphaltenes and alcohol-benzene tars enriched in hydroxyl and ester oxygen in them; that is, natural bitumen in rocks, especially above the local basis of erosion, is a product of the deep biochemical oxidation and weathering of oils. Other mechanisms of the transformation of oils into natural bitumen in the deep layers of Devonian and Carboniferous sandstones were also reflected in the composition and properties natural bitumens. 相似文献
6.
7.
来凤生姜精油化学成分研究 总被引:2,自引:0,他引:2
采用气相色谱保留指数和GC -MS -DS技术 ,对水蒸汽蒸馏法制取的来凤生姜精油分析。分离出挥发性成分 80余种 ,鉴定了 5 0种 ;主要成分是α-姜烯 ,含量为 2 4 .6 3%。 相似文献
8.
The composition of bitumen compounds from alkylated peat was determined. An increase in the yield of bitumen from alkylated peat is based on the esterification reaction. Various compounds from peat can serve as alternative raw materials for chemical industry. 相似文献
9.
在超声辅助条件下,用无水乙醇对江口县野生百合叶有效组分进行提取,并用GC-MS技术对其进行化学成分分析,鉴定出17种化合物,主要成分为:酯类化合物、酰胺类化合物、酚类化合物和烷烃类化合物等。其结果可为野生百合叶的生理活性研究和产品的开发应用提供理论依据。 相似文献
10.
11.
N. M. Joye Jr. A. T. Proveaux R. V. Lawrence 《Journal of the American Oil Chemists' Society》1973,50(4):104-107
The neutral fractions from gum, wood and tall oil rosins were isolated and examined by gas chromatography. The major components
found were diterpene aldehydes and alcohols. Smaller quantities of diterpene hydrocarbons and monoterpenes were identified.
The differences in the composition and concentrations of the neutral fractions appear to explain some of the differences in
physical characteristics of the three types of rosin.
S. Reg. ARS, USDA. 相似文献
12.
13.
M. H. Jee 《Journal of the American Oil Chemists' Society》1984,61(4):751-753
The fat fromTheobroma bicolor was analyzed for glyceride content by thin layer chromatography (TLC), and for fatty acid composition and triglyceride (carbon
number) composition by gas liquid chromatography (GLC). The fat was then separated into glycerides of different degrees of
unsaturation by means of silver nitrate TLC. Then, the bands were examined by GLC before and after conversion to methyl esters.
From the results obtained, the distribution of the fatty acids on the individual glycerides was calculated. The fat consisted
of 96.5% triglyceride with only 2.5% diglyceride and 1.7% free fatty acid. The major fatty acids present were 42.3% C18:0,
45,2% C18:1, and 6.0% C16:1. Most of the triglycerides were of carbon number 52 (18.0%) and 54 (77.6%). The major triglycerides
were 38.6% 1-stearyl-2,3 diolein (SOO), 25.4% 2-oleyl-1,3 distearin (SOS) and 13.8% 1-palmito-2-oleyl-stearin (POS). Only
44.3% of the fat consisted of monounsaturated triglycerides. 相似文献
14.
15.
Gloria Márquez-Ruiz Rafael Garcés Manuel León-Camacho Manuel Mancha 《Journal of the American Oil Chemists' Society》1999,76(10):1169-1174
Thermoxidative stability was evaluated in triaclyglycerols (TAG) from the oils of the mutant sunflower lines CAS-3, CAS-4,
and CAS-8 (with a high percentage of stearic acid), CAS-5 (with a high percentage of palmitic acid), all from standard highlinoleic
genetic backgrounds, and the mutant sunflower line CAS-12 (with a high percentage of palmitic acid), from a high-oleic genetic
background. These oils contained unusually high contents of TAG molecular species with one or two saturated fatty acids at
the sn-1,3 positions. Purified total TAG devoid of tocopherols were subjected to controlled thermoxidative treatment at 180°C. Polymerized
TAG were determined at 2-h intervals for 10 h. After this time, total polar compounds, oxidized TAG monomers, TAG dimers,
and TAG oligomers were determined. TAG from highly saturated sunflower oils with levels of linoleic acid similar to those
found in conventional sunflower oils (40–50%) showed enhanced thermal stability. In these TAG, the amount of polar compounds
formed during the thermoxidative treatment was similar to that formed in the high oleic acid line. Excellent results were
obtained for the TAG of the CAS-12 oil, which had the highest thermal stability, producing half the amount of polar compounds
as the conventional line and less than two-thirds that of the high-oleic line. 相似文献
16.
采用NTG和UV连续处理绿色木霉IFO31137菌株(TTichodermaviTideIFO31137),并对菌株纤维素酶活力和酶吸附率作双重比较,获得突变株SO-465。其微晶粉末纤维素酶(Avicelase)活力提高8.2倍,酶对废物的吸附率增加约5倍。突变菌株对四种纤维素底物(微晶粉末纤维素、滤纸、纸浆纤维和KCFloc)的水解率分别为87.5%、81.9%、90.5%和83.2%,比原始菌株增加幅度为101%、230%、83%和74%。 相似文献
17.
N. G. Vyazova L. N. Belonogova V. P. Latyshev E. A. Pisar’kova 《Solid Fuel Chemistry》2008,42(5):274-277
Coals from the Yurty coal occurrence were studied. It was found that the samples were brown non-coking coals with low sulfur contents (to 1%) and high yields of volatile substances (V daf to 53.4%). The high heat value of coals Q s daf was 20.6–27.7 MJ/kg. The humic acid content varied from 5.45 to 77.62%. The mineral matter mainly consisted of kaolinite, α-quartz, and microcline. The concentration of toxic elements did not reach hazardous values. 相似文献
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19.
本文采用X射线荧光光谱仪(XRF)、X射线衍射仪(XRD)、激光粒度仪、综合热分析仪(DTA/TG)、场发射扫描电镜(FE-SEM)以及透射电镜(TEM)等测试手段对福建龙岩高岭土进行了组成及结构的研究.结果表明:龙岩高岭土的矿物组成主要由高岭石、多水高岭石和伊利石组成.一定量伊利石的存在是龙岩高岭土的化学组成中含有较高K2O组分的直接原因,这导致其耐火度不高.龙岩高岭土的显微结构为片状和管状混合结构,多水高岭石呈管状,结晶程度最差;高岭石呈不规则薄片状,结晶程度较差;伊利石呈板片状,晶化程度最好. 相似文献