Role of magnesium chloride on the purity and activity of ovomucin during the isolation process

Abstract: Purification of ovomucin is still an empirical technique and sometimes insufficient quantities of ovomucin are purified to allow characterization. Here we aimed to investigate the effect of MgCl2 on the purity and bioactivity of ovomucin during isoelectric precipitation process and to develop an effective protocol to prepare pure ovomucin with high bioactivity. It was found that addition of MgCl2 is an alternative approach to remove lysozyme from ovomucin, and that the hemagglutination inhibition (HI) activity of ovomucin with MgCl2 against New Disease Virus (NDV) was about two times higher than the protein without salts. Thus, an improved procedure comprises a precipitation with 0.05mol/L CaCl2 followed by precipitation with 0.05mol/L MgCl2 was developed for the isolation of ovomucin. Better adhesion property of ovomucin was observed when low concentration of MgCl2 was added in the designed ELASA test, whereas the adhesion property of the pure ovomucin without salts to NDV was lower. Thus, magnesium (II) plays an important role in the activity of ovomucin, and the alternative method developed in this study may significantly facilitate the further research on the mechanism of ovomucin activity. [Copyright &y& Elsevier]