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The purpose of this study was to identify and quantify various neutral and polar lipids in certain organs of mice using high-performance thin-layer chromatography (HPTLC). Four mice infected with Schistosoma mansoni and three control mice were used for this study. At 6 weeks postinfection, the mice were necropsied, and the liver, spleen, and small intestine were removed and prepared for lipid analysis. Lipids were separated on laned, preadsorbant Analtech HPTLC-HLF 20 × 10-cm silica gel plates. Neutral lipids were separated using petroleum ether-diethyl ether-glacial acetic acid (80:20:1) mobile phase and were detected by spraying with 5% ethanolic phosphomolybdic acid detection reagent. Polar lipids were separated with chloroform-methanol-deionized water (65:25:4) mobile phase and detected using 10% cupric sulfate in 8% phosphoric acid reagent. The analyzed neutral lipids were free sterols, free fatty acids, and triacylglycerols. Using HPTLC, no significant differences were found in these lipids between the infected and uninfected mice organs. The polar lipids analyzed were phosphatidylcholine (PC) and phospatidylethanolamine (PE). There was a significantly higher PC content in the liver and small intestine of the uninfected mice compared with that of infected mice.

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High-performance thin-layer chromatography was used to examine the phospholipid profiles in the urine of Echinostoma caproni infected mice, uninfected mice, and humans. Phospholipids were extracted from urine with chloroform-methanol, 2:1, and determined on silica gel plates with 19 lanes and a concentration zone that were developed with chloroform-methanol-water, 65:25:4. Separated zones were detected by charring with aqueous cupric sulfate reagent and quantified by visible mode slit-scanning densitometry at 370 nm. Ninhydrin spray reagent was used to confirm the presence of phosphatidylethanolamine and spiking analyses were used to confirm the identity of phosphatidylcholine in human urine. Lysophosphatidylcholine was found in human but not mouse urine. Comparison of chromatograms from the urine of infected and uninfected mice showed no qualitative or quantitative differences in the phospholipid profiles, suggesting that urinary phospholipids may not serve as biological markers for trematode infection in mice. Marked differences between the overall polar lipid profiles of mouse and human urine suggest that mice may not be useful models for humans in analyses of the effects of metabolic and infectious diseases on polar lipids.

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The fatty acid compositions of the total lipid, neutral and polar lipid fractions in the liver and muscle of Capoeta sieboldii and Capoeta baliki from Tödürge Lake were determined. Major fatty acids found in total lipid (TL) and neutral lipid (NL) in liver and muscles were C16:0, C16:1 n-7, C18:1 n-9, C18:1 n-7, C20:4 n-6, C20:5 n-3, C22:5 n-3, and C22:6 n-3. Beside these acids, C18:0 was another notable fatty acid in polar lipid (PL) fraction of the tissues investigated. The n-3/n-6 ratio, which is an indicator of health benefits of fish oils, was between 2.89 (PLs of liver) and 5.84 (PLs of muscle) in C. baliki, while it was found between 1.43 (PLs of liver) and 2.52 (NLs of muscle) in C. sieboldii. C. baliki was the excellent species in terms of polyunsaturated fatty acid (PUFA) levels in TL (43.92% in muscle) and PLs (52.94% in muscle) and C22:6 n-3 amounts (docosahexaenoic acid; DHA) were responsible for these high percentages. These results suggest that Capoeta species investigated have high nutritive value in terms of polyunsaturated fatty acids for human nutrition.

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Silica gel high-performance thin-layer chromatography (HPTLC) was used to study the effects of both Schistosoma mansoni infection and high temperatures on the neutral and polar lipid content of whole bodies of Biomphalaria glabrata snails. Neutral lipids were determined using petroleum ether-diethyl ether-glacial acetic acid (80:20:1) mobile phase, phosphomolybdic acid detection reagent, densitometry at 610 nm, and polar lipids with chloroform-methanol-water (65:25:4) mobile phase, cupric sulfate-phosphoric acid reagent, and scanning at 370 nm. The high-temperature experiments were done at ambient (22–24°C), 28°C, and 34°C. Snails were maintained at these temperatures for 7 days prior to necropsy. Extracts of their bodies were then analyzed by HPTLC to determine changes that occurred in the lipid content as a function of temperature and to compare unexposed to exposed cultures at each temperature. At 4 weeks postinfection (PI), the 34°C exposed snails had significantly lower amounts of free sterols than the unexposed culture. At 4 weeks PI, the 34°C exposed snails also had significantly lower amounts of free sterols than the ambient and 28°C exposed snails. At 6 weeks PI, ambient exposed snails had significantly lower free fatty acids and significantly higher phosphatidylcholine than unexposed snails. The 28°C exposed snails had significantly lower amounts of free sterols and phosphatidylethanolamine than the unexposed snails. The 28°C exposed snails also had significantly higher amounts of free sterols, triacylglycerols, and phosphatidylcholine than the ambient snails and significantly lower amounts of free fatty acids than the ambient temperature snails. The ambient exposed snails had significantly lower amounts of free sterols than the 28°C and 34°C snails. The 34°C exposed snails had significantly lower amounts of triacylglycerols than the ambient temperature and 28°C exposed snails. At 8 weeks PI, the 28°C exposed snails had significantly higher amounts of phosphatidylcholine than the unexposed snails. These findings suggest that high temperature and S. mansoni infection had individual and combined deleterious effects on the lipid metabolism of the snails.

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In nine mammalian species (mouse — cattle: 21.5 g–503 kg) lung total phospholipids (PL), alveolar surfactant phosphatidylcholine (PC) and sphingomyelin (SM) fatty acyl (FA) chain composition was tested relating to body mass (BM) and resting respiratory rate (RRR) associated adaptations. In PL, PC and SM oleic acid (C18:1 n9) provided negative correlations with RRR. Palmitic acid (C16:0) was strongly, positively correlated with RRR in the pulmonary PLs, and myristic (C14:0) acid correlated positively with RRR in the surfactant PCs. In pulmonary PLs negative allometry was found for myristic, palmitic, palmitoleic (C16:1 n7) and docosahexaenoic (C22:6 n3) acids and total saturation, while oleic (C18:1 n9), alpha-linolenic (C18:3 n3) and gondoic (C20:1 n9) acids, total n9 FA s and monounsaturation increased allometrically. In surfactant PC FA s palmitic acid provided negative, while oleic acid and monounsaturation positive allometry; the average FA chain length (ACL) was identical in all species. Surfactant SM FA composition was fully species independent for palmitic and arachidonic acids, total saturation, monounsaturation and ACL. The in vivo lipid peroxidation rate was species independent. The variability of lung PLs was consonant with the “membrane pacemakers theory”, while surfactant PC composition was mostly related to RRR.

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Pedneault, K., Angers, P., Avis, T., Gosselin, A. & Tweddel, R.J. (2007): Fatty acid profiles of polar and non-polar lipids of Pleurotus ostreatus and P. cornucopiae var. ‘ citrino-pileatus’ grown at different temperatures. Mycol. Res. , 111 , 1228

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the sn -glycerol-3-phosphate in bacterial phospholipids; (ii) the hydrocarbon chains in archaeal polar lipids are bonded to the glycerol moiety exclusively by ether linkages, in contrast to bacterial lipids, most of which have ester linkages; (iii

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Acta Alimentaria
Authors: A. Zervou, V. Sinanoglou, G. Papadas, N. Thomaidis, D. Meimaroglou, and S. Miniadis-Meimaroglou

336 344 Sinanoglou. V.J. & Miniadis-Meimaroglou, S. (1998): Fatty acid of neutral and polar lipids of (edible) Mediterranean cephalopods. Fd Res. int. , 31 , 467

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Abstract  

The phase behaviour and phase stability of lipids are of importance in an understanding of the biological functions of cell membranes. Among a variety of physical techniques employed to study the phase behaviour and structural properties of polar lipids, differential scanning calorimetry and X-ray diffraction have proved to be successful and are the most frequently used methods. Applications involving a combination of the two techniques, particularly when synchrotron radiation is used as the light source of X-ray diffraction, are reviewed in this article.

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In the present study, isothermal microcalorimetry was introduced as a tool to investigate properties of starch retrogradation during the first 24 h. The study was made on purified amylose and amylopectin from corn, as well as on native starches, such as wheat, potato, maize, waxy maize and amylomaize, differing in their amylose content. The results were obtained in the form ofP-t traces (thermal powervs. time), and integration of these traces gave a net exothermic enthalpy of reaction, caused by the crystallization of amylose and amylopectin. TheP-t traces reflected the quantities of amylose and amylopectin in the starch studied. Depending on the amylose content and the botanical source of the starch, the rate of crystallization of amylose was high and predominated over that of amylopectin during the first 5–10 h. The contribution from amylose crystallization to the measured exothermic enthalpy was very substantial during this period. After ∼10 h, amylose crystallized at a lower constant rate. During the first 24 h, amylopectin crystallized at a low steady rate. The exothermic enthalpies obtained by the isothermal microcalorimetric investigations during the first 24 h of retrogradation were generally low in relation to the endothermic melting enthalpies observed by differential scanning calorimetry (DSC) measurements after 24 h of storage. The discrepancies in enthalpy values between the two methods are discussed in relation to phase separation and the endothermic effects owing to the decrease in polymer-water interactions when polymer-rich regions in the starch gel separate. Besides the exothermic enthalpies obtained, theP-t traces also made it possible to study the initial gelation properties of amylose from different botanical sources. The present study further demonstrated that isothermal microcalorimetry can provide a possible way to investigate the antistaling effect of certain polar lipids, such as sodium dodecylsulphate (SDS) and 1-monolauroyl-rac-glycerol (GML), when added to starches of different botanical origin. The net exothermic heat of reaction for starch retrogradation during the first 24 h was decreased when GML or SDS was added to the starch gels. The recordedP-t traces also showed how the effect of the added lipid influenced different periods during the first 24 h of starch retrogradation, and that the effect depended mainly on the amylose content, the botanical source of the starch, and the type of lipid used. When GML or SDS was added to waxy maize, the isothermal microcalorimetric studies clearly indicated some interaction between amylopectin and the polar lipids. These results concerning the action of anti-staling agents are further discussed in relation to the helical inclusion complexes formed between amylose-polar lipid and amylopectin-polar lipid.

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