Phospholipids of fish gills

Lipids were extracted from gill filaments of nine species of fish. Individual phospholipids as a percentage of the total were determined. These data revealed a pattern which did not appear to vary between pre- and postspawning salmon or among fish living at greatly differing ocean depths.     

Phospholipids of menhaden muscle

The phospholipids of menhaden fish muscle represent about 0.5% of the wet weight. They were separated by fractionation on a silica gel column. Choline glycerophosphatides were the major components, about 60%. Ethanolamine and serine glycerophosphatides accounted for about 20%, and sphingomyelin and less well-characterized components for the rest. The fatty acid composition of the CGP,¹ EGP¹ + SGP,¹ and triglyceride preparations were compared. The EGP + SGP fraction contained 20% stearic acid whereas the neutral or CGP fractions had only 2–4%. The phospholipids contained about 30% of docosa-hexaenoic acids compared to about 10% in the neutral fraction.     

精制磷脂的研究进展

近年来,高纯度磷脂在医药、化妆、食品工业中的需求很大。文献报道精制磷脂的方法很多,本文论述了溶剂法、超临界萃取技术、膜技术、柱层析、HPLC制备等方法的进展情况。     

Phospholipids from palm-pressed fiber

Palm-pressed fiber, a by-product of palm oil milling, was extracted successively with hexane and 95% ethanol; the ethanol extracts yielded 46,800 ppm of phospholipids. The phospholipid composition, as analyzed by HPLC coupled with an ELSD, was found to be predominantly PC, PE, phosphatidylglycerol, and PA; as expected, the FA were more unsaturated than the TAG. Palm-pressed fiber is estimated to be able to provide 21,645 tonnes of palm lecithin based on the present total world production of fresh fruit bunches and thus be an alternative source of lecithin, which is normally obtained from soybeans.     

Non-Enzymatic Browning Reactions of Phospholipids

The formation and properties of the fluorescent compounds originated in the browning reactions of phospholipids have been investigated. The compounds exhibited fluorescence with excitation maximum 345–350 nm and emission maximum at 420–430 nm, which were similar to those of lipofuscin and fluorescent substances derived from the reaction of oxidized fatty acids with glutathione. The fluorescence of the compound was affected neither with the pH 2–11 nor by treatment with sodium borohydride. The fluorescent compounds formed in the browning reaction of peroxidized phosphatidylethanolamine are produced, mainly, by interaction of the amine group of phosphatidylethanolamine and saturated aldehydes produced through the decomposition of fatty acid hydroperoxides of phosphatidylethanolamine. Phospholipids do not interact per se with bovine serum albumin, and their interaction is similar to that of polyunsaturated fatty acid hydroperoxides: the phospholipids give secondary products (aldehydes) that subsequently react with protein.     

Characterization of Amaranthus hybridus Phospholipids

The seeds of Amaranthus hybridus contain about 0.66 percent phospholipids. Silica gel column chromatography and analysis of eluates as such and after acid hydrolysis using paper and thin layer chromatographic techniques have shown that the major constituents of A. hybridus seed phospholipids are phosphatidyl ethanolamine, phosphatidyl choline and phosphatidyl inositol. The other two identified components present in small amount are sphingomyelin and lysolecithin.     

Phospholipids and sports performance

Phospholipids are essential components of all biological membranes. Phosphatidylcholine (PC) and Phosphatidylserine (PS) are Phosphatidyl-phospholipids that are required for normal cellular structure and function. The participation in physical activity often challenges a variety of physiological systems; consequently, the ability to maintain normal cellular function during activity can determine sporting performance. The participation in prolonged intense exercise has been shown to reduce circulatory choline concentrations in some individuals. As choline is a pre-cursor to the neurotransmitter Acetylcholine, this finding has encouraged researchers to investigate the hypothesis that supplementation with PC (or choline salts) could enhance sporting performance. Although the available data that evaluates the effects of PC supplementation on performance are equivocal, acute oral supplementation with PC (~0.2 g PC per kg body mass) has been demonstrated to improve performance in a variety of sporting activities where exercise has depleted circulatory choline concentrations. Short term oral supplementation with soy-derived PS (S-PS) has been reported to attenuate circulating cortisol concentrations, improve perceived well-being, and reduce perceived muscle soreness after exercise. More recently, short term oral supplementation (750 mg per day of S-PS for 10 days) has been demonstrated to improve exercise capacity during high intensity cycling and tended to increase performance during intermittent running. Although more research is warranted to determine minimum dietary Phospholipid requirements for optimal sporting performance, these findings suggest that some participants might benefit from dietary interventions that increase the intakes of PC and PS.     

Phospholipids of pork muscle tissues

The lipids extracted from four locations on a hog carcass were fractionated into nonphospholipids, phosphatidyl ethanolamine, phosphatidyl serine, lecithins, and sphingomyelins. The identities of phospholipid fractions were established and their quantitative contents were determined by three methods: gravimetrically, from analysis of the phosphorus content, and from standard curves of infrared spectra. Variations in content of a phospholipid type were noted in the carcass locations studied. Lecithin and phosphatidyl ethanolamine were found in greatest quantity. These represented ca. 61% and 31%, respectively, of the total phospholipids. The remainder was distributed between phosphatidyl serine and sphingomyelin at 5% and 3%, respectively. The phospholipid content of hog meat was found to be slightly over 0.5%. Journal Article No. 3077, Michigan Agricultural Experiment Station. Supported by research grant No. RG-8801, National Institutes of Health, U. S. Public Health Service, Department of Health, Education, and Welfare. Presented at the AOCS meeting in Toronto, Canada, 1962.     

Phospholipids of tuna white muscle

The composition of the lipids from the white muscle of five tuna fish has been determined. Total extractable lipid varied from 0.5%–10.3% of the tissue wet weight; phospholipid content ranged from 0.3%–0.6%. The separation of the phospholipid components was made by column chromatography with activated silicic acid and stepwise elution, with increasing concentrations of methanol in chloroform. The components were identified by chemical tests and infrared (IR) spectra. Tuna white musele contained an average of 0.5% phospholipid on wet weight basis; 23% was cephalin, 54% lecithin, 8% sphingomyelin, 2% phosphoinositide, with small amounts of unidentified components. Ten to 30% of the lecithin and cephalin fractions were in the form of plasmalogens. The gas-liquid chromatographic analyses of the 12–22 carbon fatty acids of the lecithin, cephalin, and neutral fractions are presented. The cephalins were characteristically high in stearie acid and low in palmitic acid, in contrast to the lecithins.     

The Nature of Cottonseed Phospholipids

Degumming of crude cottonseed oil yielded 1% of phospholipids. Repeated acetone precipitations still left 18% of triglycerides and 3.6% of gossypol. The UV-spectrum of the total phospholipids showed a λ_max at 391 mμ which was characteristic of the bound form of gossypol, possibly with the free amino group of the phosphatidyl ethanolamine present. The phospholipids were separated into a number of fractions by silicic acid column chromatography. Gossypol occurred in free form in the eluted fractions indicating cleavage during column chromatography. Analysis of the fractions by thinlayer chromatography as such and after different types of hydrolysis revealed the composition of the total phospholipids to be: phosphatidyl ethanolamine 22%, inositol phospholipids 37%, phosphatidyl choline 33% and unidentified 8%.     

氢化大豆磷脂的制备

研究了大豆磷脂的催化加氢, 讨论了其优惠工艺条件、获得了碘价为２０ ～３０ 、磷含量为３２ ％ 、氮含量为０６２ ％ 的淡黄色无难闻气味的氢化大豆磷脂产品, 收率为８０ ％ 。     

Phospholipids of environmentally stressed soybean seeds

Protein and oil content of the soybean [Glycine max (L.) Merr.] seed and the fatty acid composition of the oil can be altered by environmental stress. The objective of this study was to characterize the composition of the phospholipid (PL) from soybean seeds after exposure to drought and high temperature during seed fill. Drought stress was imposed on greenhouse-grown soybean plants at temperatures of 28 and 33‡C after the beginning of seed fill and was maintained throughout the seed-fill period. The fatty acid composition of each PL class was altered by drought and high temperature. With phosphatidylcholine and phosphatidylethanolamine, which composed 89% of the separated PL, greater proportions of 16:0 and 18:0 and lesser proportions of 18:2 and 18:3 were present in soybean seeds exposed to high temperature and severe drought. More linolenic acid and less palmitic acid were present in phosphatidylinositol. The changes were comparable to those of the triglyceride because of high temperature. The elevated temperature increased the proportion of phosphatidylcholine and phosphatidylinositol and decreased that of phosphatidylethanolamine. The effect of drought and high temperature stress on PL class and fatty acid composition has important implications on the quality of soybean seed oil and lecithin and on the ability of the seed to maintain optimum rates of metabolism in the development and germination environment.     

Phospholipids of six seed oils of malvaceae

The phospholipid fractions of six seed oils of the Malvaceae family—Gossypium barbadense (Egyptian cotton),Hibiscus cannabinus (kenaf),Hibiscus sabdarifa (roselle), two varieties ofHibiscus esculentus (okra) andAlthea rosea (ketmia, hollyhock or Egyptian hemp)—have been isolated by silicic acid chromatography. Thin-layer chromatography of these phospholipid fractions revealed that the common phosphatides were cephalins, lecithin (phosphatidylcholine) and some of their lysoforms. There were also some nonpolar constituents, especially phosphatidic acid. Phospholipid fatty acids were prepared by transesterification. Different proportions of three common fatty acids, palmitic, oleic and linoleic, have been found in the six glycerophospholipids.     

The Anionic Phospholipids of Bovine Pulmonary Surfactant

The only known compositional change in the phospholipids (PL) of pulmonary surfactant in response to a physiologic stimulus occurs around the time of birth. In most species, the predominant anionic PL changes from phosphatidylinositol (PtdIns) to phosphatidylglycerol (PtdGro). Because prior studies have shown that the change in the headgroup itself is functionally insignificant, we tested the hypothesis that the PtdIns and PtdGro contain different diacyl pairs. Experiments used electrospray-ionization mass spectrometry to determine the molecular species in PtdIns, PtdGro, and phosphatidylcholine (PtdCho) in surfactant from newborn calves and cows. The profiles for the two anionic PL were distinct. The PtdIns contained long, unsaturated fatty acid chains and no disaturated species. The PtdGro more closely resembled the profile from PtdCho. For each headgroup, the molecular species for calf and cow were similar. The differences between the two anionic PL indicate that the switch from PtdIns to PtdGro during maturation involves more than simple substitution of the headgroup, and suggest that the functional significance of the shift may reflect the different pool of diacyl pairs.     

Phospholipids of New Zealand Edible Brown Algae

Edible brown algae have attracted interest as a source of beneficial allenic carotenoid fucoxanthin, and glyco‐ and phospholipids enriched in polyunsaturated fatty acids. Unlike green algae, brown algae contain no or little phosphatidylserine, possessing an unusual aminophospholipid, phosphatidyl‐O‐[N‐(2‐hydroxyethyl) glycine], PHEG, instead. When our routinely used technique of ³¹P‐NMR analysis of phospholipids was applied to the samples of edible New Zealand brown algae, a number of signals corresponding to unidentified phosphorus‐containing compounds were observed in total lipids. NI (negative ion) ESI QToF MS spectra confirmed the presence of more familiar phospholipids, and also suggested the presence of PHEG or its isomers. The structure of PHEG was confirmed by comparison with a synthetic standard. An unusual MS fragmentation pattern that was also observed prompted us to synthesise a number of possible candidates, and was found to follow that of phosphatidylhydroxyethyl methylcarbamate, likely an extraction artefact. An unexpected outcome was the finding of ceramidephosphoinositol that has not been reported previously as occurring in brown algae. An uncommon arsenic‐containing phospholipid has also been observed and quantified, and its TLC behaviour studied, along with that of the newly synthesised lipids.     

Quantification of Phospholipids Classes in Human Milk

Phospholipids are integral constituents of the milk fat globule membranes and they play a central role in infants’ immune and inflammatory responses. A methodology employing liquid chromatography coupled with evaporative light scattering detector has been optimized and validated to quantify the major phospholipids classes in human milk. Phospholipids were extracted using chloroform and methanol and separated on C18 column. Repeatability, intermediate reproducibility, and recovery values were calculated and a large sample set of human milk analyzed. In human milk, phospholipid classes were quantified at concentrations of 0.6 mg/100 g for phosphatidylinositol; 4.2 mg/100 g for phosphatidylethanolamine, 0.4 mg/100 g for phosphatidylserine, 2.8 mg/100 g for phosphatidylcholine, and 4.6 mg/100 g for sphingomyelin. Their relative standard deviation of repeatability and intermediate reproducibility values ranging between 0.8 and 13.4 % and between 2.4 and 25.7 %, respectively. The recovery values ranged between 67 and 112 %. Finally, the validated method was used to quantify phospholipid classes in human milk collected from 50 volunteers 4 weeks postpartum providing absolute content of these lipids in a relatively large cohort. The average content of total phospholipids was 23.8 mg/100 g that corresponds to an estimated mean intake of 140 mg phospholipids/day in a 4-week old infant when exclusively breast-fed.     

卤代磷脂的合成研究

以大豆磷脂为原料,利用有机卤代试剂制备出一种新型的卤代磷脂。通过正交试验确定了该反应的最佳反应条件：温度７５℃,引发剂量４％,溶剂量１５０ｍｌ,反应时间１．５ｈ。     

Phospholipids of three xerophytic cucurbit seed oils

The composition of seed phospholipids was determined in three species of xerophytic cucurbits,Cucurbita digitata Gray,C. foetidissima HBK andApodanthera undulata Gray. The phospholipid fractions were isolated using silicic acid chromatography and quantitated by colorimetric analysis. The component phospholipids were separated using thin layer chromatography. All three species contained phosphatidylcholine, phosphatidyl-ethanolamine and phosphatidylinositol as their major component phospholipids. Analysis by gas liquid chromatography of fatty acids in total phospholipid samples revealed linoleic acid as the major component and myristic acid in significant amounts in each species. Small amounts of conjugated unsaturated fatty acids in the phospholipids of each species were determined by ultraviolet spectrometry. Close similarities in the composition of specific phospholipids were found in all species. This is Paper No. 3908 of the Arizona Agricultural Experiment Station.