Nutrients Ovalbumin

Proteins present in whole egg, yolk, and albumen (egg white) are excellent sources of nutrients, and they possess valuable functional properties. Shell eggs consist of 8-11% shell, 56-61% albumen, and 27-32% yolk. The solid content of albumen is about 11-13%, depending on the strain and on the age of the hens, and the solid content of yolk is about 52-53.5%. Albumen solids contain mainly protein, whereas lipids are the major constituents of egg yolk (92). Yolk can be separated by centrifugation into sedimented granules and a supernatant, plasma. The granules contain the major part of the yolk proteins. The main proteins in albumen and yolk are ovalbumin, ovotransferin, lysozyme, ovomucoid, ovomucin, and immunoglobulin Y (93). 

Storage. Certain proteins serve as a reservoir of essential nutrients. For example, ovalbumin in bird eggs and casein in mammalian milk are rich sources of organic nitrogen during development. Plant proteins such as zein perform a similar role in germinating seed. 

Therefore, the regions composing the trunk (note particularly the DNA of the somites) of serum cultured embryos contained proportionately more of the total embryo DNA, RNA, and protein than did the trunk regions of ovalbumin cultured embryos. Although the mechanism by which these nutrients affected regional growth have not been elucidated, comparisons with explants cultured on various dilutions of whole egg homogenate medium have indicated that the results obtained with serum... 

Two proteins of the avian egg white, ovalbumin and conalbumin, provided a second example of nutrient protein complementation. In the previously discussed studies with ovalbumin, this protein was either obtained from a commereial source or prepared by the classic salt precipitation procedure (Kekwick and Cannan, 1936). For the study on ovalbumin utilization to be discussed in the following section, ovalbumin was prepared by column chromatography on carboxymethyl cellulose (Rhodes et al., 1958) which provided this protein in greater yields and... 

This experiment provided an overall picture of the distribution of ovalbumin and products derived from this nutrient protein in the ex-... 

Eggs contain the complete food supply for the embryo chick and consequently are rich in essential nutrients. Since they contain very little carbohydrate they cannot be considered as a complete food for humans. The white of eggs consists almost entirely of protein with ovalbumin constituting 70% of the total. The yolk contains the phosphoprotein vitellin and 21-33% of fat including phospholipids and cholesterol. 

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