An Efficient Preparation and Structural Characterization of Sialylglycopeptides from Protease Treated Egg Yolk

Abstract
Delipidated egg yolk (DEY) was digested with protease. The digest was ultrafiltered using a molecular weight cut-off of 10,000, and the UF permeate was treated with a reverse osmosis membrane. The resulting sialylglycopeptides-rich fraction was purified by the combination of anion exchange and gel filtration chromatography. Two major sialylglycopeptides, A-I and A-II, were characterized as biantennary complex type sialylglycopeptides having one or two N-acetylneuraminic acid and 1 - 3.5 amino acids including one asparagine residue by composition analyses and 1H NMR spectroscopy.