COMPARATIVE STUDIES OF EGG ALBUMIN FROM DIFFERENT SOURCES

Document Type : Original Article

Authors

Agric. Bioch. Dept., Fac. Agric., Zagazig Univ., Egypt

Abstract

This work describes the use of different methods to study egg white proteins from hen, duck and quail. For this purpose, protein content determination, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Urea-polyacrylamide gel electrophoresis (Urea-PAGE), amino acids composition and Fourier Transform Infrared (FTIR) Spectroscopy were used to compare egg white proteins from these poultry species. Protein content, ranging from 71.31 to 72.36%. Quail egg white showed the lowest protein concentration (71.31%). The highest protein concentration was observed in duck egg white, which reached 72.36%. The analysis by SDS-PAGE, egg white proteins presented a wide range of relative molecular masses. The main egg white proteins are ovalbumin, ovotransferrin, ovomucoid and lysozyme. The contents of the hydrophobic amino acids residues (Pro, Gly, Ala, Val, Ile, Leu, Phe) are 34.54%, 34.95% and 34.94% for egg albumin from hen, duck and quail, respectively. The migration in Urea-PAGE into cathode direction indicated that duck egg white protein and quail egg white protein were much faster than hen egg white protein referring to bigger positive charges. Also, the secondary structure of protein was observed by FTIR.

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