SIALYLOLIGOSACCHARIDES OF DELIPIDATED EGG-YOLK FRACTION

Delipidated egg yolk (DEY) was homogenized and centrifuged. The supernatant was dialyzed by ultrafiltration using a molecular weight cut-off of 1,000. The asparagine-linked oligosaccharides in the concentrate were liberated from protein by hydrazinolysis and labeled with UV-absorbing p-amionbenzoic ethyl ester (ABEE). The ABEE-derivatized oligosaccharides were fractionated by anion exchange and reverse-phase HPLC. The total sialyloligosaccharides from the water-soluble DEY fraction, were about 47.7% monosialyl and 50.6% disialyloligosaccharides. The structures of 3 predominant sialyloligosaccharides were determined by NMR. They were of the biantennary complex-type, accounting for about 33.6% of the total sialyloligosaccharides of the DEY water-soluble fraction.