Egg lipoprotein

Lipids are involved in a number of essential processes in the growth and reproduction of marine invertebrates. Membrane lipids, primarily phospholipids and sterols, combine with membrane proteins to form insoluble complexes that are important in membrane structure. Many marine invertebrates have oil droplets within cells of hepatic-type tissues. These droplets are primarily triacylglycerols or wax esters and serve as energy stores. Finally, lipids occur in water-soluble lipoproteins where phospholipids, triacylglycerols, and sterols are combined with various apoproteins. Lipids are transported between various tissues via hemolymph lipoproteins. Female-specific lipoproteins occur in the hemolymph and eggs of adult females of many marine invertebrates. These egg lipoproteins provide protein and lipid for the development of larvae after they hatch from the... 

Ovaries from marine invertebrates often contain high amount of lipoproteins. Wallace et al. (1967) proposed the term lipovitellin for the high density lipoproteins in the eggs of invertebrates which are the major yolk proteins of invertebrates. Because the egg lipoprotein of crustaceans also contains carotenoid and carbohydrate, it has also been referred to as a lipo-glycocarotenoprotein complex or a carotenoid-lipo(glyco)protein (Tometal. 1987a Zagalsky 1976).The... 

The eggs of the marine polychaete, Perinereis cultrifera, contain a lipovitellin with 16% lipid and five peptides (Table 7 Baert et al. 1984). Egg lipoproteins have been isolated from two mollusks (Table 2 scallop, Pecten maximus Table 7 cuttlefish. Sepia officinalis). The percent lipid of the lipoprotein from S. officinalis and P. maximus was 19 and 15%, respectively (Fuji 1960 Zagalsky et al. 1967). The molecular mass of S. officinalis was 2.5 X 10 daltons with phospholipid as the principal lipid. 

The principal pigments of crustacean hemolymph and egg lipoproteins are j8-carotene, astaxanthin, and canthaxanthin. There is generally a shift in the maximum in the carotenoid bound to the lipoprotein relative to the maximum of the free carotenoid. 

In terrestrial animals, cyclodienes such as dieldrin, like other refractive lipophilic pollutants, can be excreted in their unchanged forms, notably with lipoproteins, which are exported into milk (mammals), eggs (birds, reptiles, insects), or developing... 

HDL Hi -dcnsity lipoprotein HEL Hen egg white lysozyme HEPE Hydroxyeicosapentanoic acid HEPES N-2-... 

Egg yolk contains mainly lipids (32 34%), proteins (16%), saccharides, mineral compounds, vitamins, dyes and water (48%). It is formed by two distinguishable fractions plasma and granules. The plasma contains mostly lipids (90% of total solids) and proteins. Granules contain mainly acidic phosphoproteins (fosvitin, lipovitellins and low-density lipoproteins), which are soluble only in higher ionic strength water solutions. 

Cholesterol-rich lipoproteins of the LDL type are particularly important in the development of arteriosclerosis, in which the arterial walls are altered in connection with an excess plasma cholesterol level. In terms of dietary physiology, it is important that plant foodstuffs are low in cholesterol. By contrast, animal foods can contain large amounts of cholesterol—particularly butter, egg yolk, meat, liver, and brain. 

Separate yolks of chicken eggs from egg white and discard egg white. Wash the yolks carefully with water to remove adhering egg white. Suspend the yolks in 5 vol. Soln. A by vigorous stirring. Precipitate lipids and lipoproteins by addition of 6 ml Soln. B and 15 ml Soln. C per 100 ml yolk suspension. Stir at RT for 30-60 min and spin at 5000 x g for 10 min. Wash the pellet with a small volume of Soln. A (about 20 ml per yolk) and centrifuge again. Combine the supernatants and filter through a paper filter. Add Soln. D to the clear filtrate to a final concentration of 30 mM EDTA. 

Yamamoto, Y. and Omori, M. 1994. Antioxidative activity of egg yolk lipoproteins. Biosci. Biotechnol. Biochem. 58 1711-1713. 

Nakagawa, H. and Tsuchiya, Y. (1971). Study of rainbow trout eggs. III. Determination of lipid composition of fatty drops and lipoproteins. Journal of the Faculty of Fisheries and Animal Husbandry, Hiroshima University 10,11-19. 

Many food colloids are stabilized from proteins from milk or eggs [817]. Milk and cream, for example, are stabilized by milk proteins, such as casein micelles, which form a membrane around the oil (fat) droplets [817]. Mayonnaise, hollandaise, and bearnaise, for example, are O/W emulsions mainly stabilized by egg-yolk protein, which is a mixture of lipids (including lecithin), proteins, and lipoproteins [811,817]. The protein-covered oil (fat) droplets are stabilized by a combination of electrostatic and steric stabilization [817]. Alcohols may also be added, such as glycerol, propylene glycol, sorbitol, or sucrose sometimes these are modified by esterification or by... 

Anton, M., Martinet, V., Dalgalarrondo, M., Beaumal, V., David-Briand, E., Rabesona, H. 2003. Chemical and structural characterisation of low-density lipoproteins purified from hen egg yolk. Food Chem 83 175-183. 

Lipoproteins. These are combinations of lipids with protein and have excellent emulsifying capacity. Lipoproteins occur in milk and egg yolk. 

The addition of salt to the egg yolk solution during the preparation of the solutions disrupts the granules and provides additional surface active material for adsorption, such as a- and yS-lipovitellins and phosvitin. In this regard, Chang et al. (1972) observed with an electron microscope a continuous speckled layer around oil drops and also a fibrous membrane on the surface of drops after they were washed with water. The electron-dense particles in the speckled layer were interpreted to be egg yolk lipoproteins and the fibrous material to be livetin-phosvitin complex. 

Kiosseoglou, V. D. and Sherman, P. 1983. Influeneeof egg yolk lipoproteins on the rheology and stability of o/w emulsions and mayonnaise 1. Viscoelasticity of groundnut oil-in-water emulsions and mayonnaise. J. Texture Stud. 14 397-417. 

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