Liquid chromatography lipid analysis

Passi, S., Rothschildboros, M.C., Fasella, P., Nazzaroporro, M. and Whitehouse, D. (1981) An application of high performance liquid chromatography to analysis of lipids in archaeological samples. Journal of Lipid Research 22, 778 784. 

The purity of all lipids and anthracyclines exceeded 98% based on thin-layer chromatography (TLC) and/or high-performance liquid chromatography (HPLC) analysis, performed as described by Barenholz and coworkers (38,49,50). 

MA Rouet-Mayer, O Valentova, E Simond-Cote, J Daussant, C Thevenot. Critical analysis of phospholipid hydrolyzing activities in ripening tomato fruits. Study by spectrofluorimetry and high performance liquid chromatography. Lipids 30 739-746, 1995. 

Christie, W. W. (1997). Analysis of fatty acids by high-performance liquid chromatography. Lipid Technol. 9,124—126. 

There are two main procedures for measuring PI 3-kinase activity which measure lipid kinase activity in intact cells or broken cell lysates respectively, and both rely on detecting the transfer of the y- phosphate of ATP to the D-3 position of the inositol head group of phosphoinositide lipids. The first method relies on metabolic labeling of intact cellular pools of ATP with [32P]Pi followed by lipid extraction (3,4) and separation of the phosphorylated lipids by high-performance liquid chromatography (HPLC) analysis (5). The advantages of this procedure are ... 

Chromatography, High-Temperature Gas-liquid, in lipid Analysis (Vaver and... 

MacDonald, I. A., Williams, C. N., and Musial, B. C., 3a,7a, and 12a-hydroxy group specific enzymic analysis of biliary bile acids Comparison with gas-liquid chromatography. /. lipid Res. 20, 381-385 (1979). 

Chromatography, High Temperature Gas-Liquid, in Lipid Analysis... 

Takagi, T., and Itabashi, Y. (1981) Occurrence of Mixtures of Geometrical Isomers of Conjugated Octadecatrienoic Acids in Some Seed Oils Analysis by Open-Tubular Gas Liquid Chromatography and High Performance Liquid Chromatography, Lipids 16,546-551. 

Chan, H.W.-S. and Levett, G. Autoxidation of methyl linolenate analysis of methyl hydroxyhnolenate isomers by high performance liquid chromatography. Lipids 12,837-840 (1977b). 

Analysis of a-Tocopherol in Red Blood Cells by Gas-Liquid Chromatography Lipids 15(2) 135 (1980) CA 93 3217g... 

Takagi, T. Ando, Y. Stereospecific analysis of triscy- n-glycerols by chiral high-performance liquid chromatography. Lipids 1991, 26, 542-547. 

High performance liquid chromatography (HPLC) has been by far the most important method for separating chlorophylls. Open column chromatography and thin layer chromatography are still used for clean-up procedures to isolate and separate carotenoids and other lipids from chlorophylls and for preparative applications, but both are losing importance for analytical purposes due to their low resolution and have been replaced by more effective techniques like solid phase, supercritical fluid extraction and counter current chromatography. The whole analysis should be as brief as possible, since each additional step is a potential source of epimers and allomers. 

D1 (10,17S-docosatriene) from DHA using tandem liquid chromatography-photodiode array-electrospray ionization-tandem mass spectrometry (LC-PDA-ESI-MS-MS)-based lipidomic analysis have been documented in ischemic brain [4] and retinal pigment epithelium [5], This new lipid is called neuroprotectin D1 (1) because of its neuro-protectiveproperties in brain ischemia-reperfusion [4] and in oxidative stress-challenged retinal pigment epithelial cells [5] (2) because of its potent ability to inactivate proapoptotic signaling (see apoptosis, Ch. 35) [5] and (3) because it is the first identified neuroprotective mediator derived from DHA. 

Gas-liquid chromatography is a very useful technique in lipid analysis, particularly for the separation of very similar compounds within classes. Because of the wide variations in structure and properties between classes it is not usually possible to resolve members of different classes on the same column. GLC is useful for both quantitative and qualitative analysis and also in the investigation of lipid structure. 

Chlorella sorokiniana var. pacificensis were treated with 180 ppm O3 for 50 min in autotrophic media. Lipids were extracted by using Chloroform/methanol and prepared for gas-liquid chromatography (GLC) as described by Frederick and Heath (24). The average % concentration of fatty acids were calculated from 3 GLC runs in 5 separate samples. The O3/O2 column refers to ratios of average % concentration and represents standard deviation. Confidence Level was calculated by least squares analysis. 

Fig. 4.5.2 Actual strategies for CDG diagnosis. Initial investigations on CDG patients are routinely carried out by isoelectric focusing (IEF) of serum transferrin. With a CDG type I pattern, subsequent analysis should imply determination of phosphomannomutase (PMM) and phos-phomannose isomerase (PMI) activities. Further studies, like analysis of the lipid-linked- and protein-bound-oligosaccharides, determination of enzyme or sugar transporter activities and molecular biology studies often have to be performed in more specialised laboratories. HPLC High-performance liquid chromatography, TLC thin-layer chromatography...

Alme B, Bremmelgaard A, Siovall J, Thomassen P (1977) Analysis of metabolic profiles of bile acids in urine using a lipophilic anion exchanger and computerized gas-liquid chromatography-mass spectrometry. J Lipid Res 18 339-362... 

Gas-liquid chromatography separates volatile components of a mixture according to their relative tendencies to dissolve in the inert material packed in the chromatography column and to volatilize and move through the column, carried by a current of an inert gas such as helium. Some lipids are naturally volatile, but most must first be derivatized to increase their volatility (that is, lower their boiling point). For an analysis of the fatty acids in a sample of phospholipids, the lipids are first... 

Sample preparation is probably the most important step in any analytical procedure. Poor preparation of lipid samples will only yield inferior or questionable results. Some commonly performed sample-preparation procedures for gas-liquid chromatographic (GC) analysis of fatty acids in food samples are introduced in this unit. Since the introduction of gas chromatography in the 1950s, significant progress has been made in fatty acid analysis of lipids however, fatty acid methyl esters (FAMEs) are still the most commonly used fatty acid derivative for routine analysis of food fatty acid composition. 

Ackman, R.G., 1991. Application of gas-liquid chromatography to lipid separation and analysis. In Analysis of Fats, Oils and Lipoproteins (E.G. Perkins, ed.) pp. 270-300. American Oil Chemists Society, Champaign, 111. 

Caboni, M.F. and Rodriguez-Estrada, M.T. 1997. High-performance liquid chromatography coupled to evaporative light scattering detection in lipid analysis Some application. Seminars in Food Analysis 2 159-169. 

Fig. 30 Silver ion high-performance liquid chromatography (Ag-HPLC-FID) with flame ionization detector (FID) analysis of the triacylglycerols of chromatographed Crepis alpina seed oil. Ag-HPLC-FID conditions 0.5-mg sample 5-micron Chromspher Lipids column (Chrompack International, Middelburg, The Netherlands) (4.6 X 250 mm) mobile phase 0.5% acetonitrile in hexane (v/v) flow rate 1.0 ml/min FID. Chromatogram peak triacylglycerol fatty acid abbreviations S, saturated (palmitic and stearic) O, oleic L, linoleic and Cr, crepenynoic fatty acids.

However, in a more recent paper, Caboni et al. described that the aforementioned method was not applicable for all types of food products (32). Hence, only 30% and 53% of the PL of a total lipid extract of cheese and dried egg powder, respectively, were recovered. High-performance liquid chromatography analysis revealed that the acidic phospholipids PG and PI were not... 

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