Studies of the neutral trisaccharides of goat (Capra hircus) colostrum and of the one- and two-dimensional 1H and 13C NMR spectra of 6'-N-acetylglucosaminyllactose

Abstract

Four neutral trisaccharides were isolated from goat colostrum by dialysis, and ion-exchange, activated charcoal column, preparative paper, and Bio-Gel P-4 column chromatography. The following structures were elucidated by GC analysis of hydrolysis products and by 400-MHz 1H NMR spectroscopy: alpha-L-Fuc p-(1-->2)-beta-D-Gal p-(1-->4)-D-Glc, alpha-D-Gal p- (1-->3)-beta-D-Gal p-(1-->4)-D-Glc, beta-D-Gal p-(1-->3)-beta-D-Gal p-(1-->4)-D-Glc, and beta-D-Gal p-(1-->6)-beta-D-Gal p-(1-->4)-D-Glc. beta-D-Glc pNAc-(1-->6)-beta-D-Gal p-(1-->4)-D-Glc, previously reported to be present in goat milk, was not detected in this study. beta-D-Glc pNAc-(1-->6)-beta-D-Gal p-(1-->4)-D-Glc (6'-N- acetylglucosaminyllactose) was prepared by beta-D-galactosidase digestion of beta-D-Gal p-(1-->3)[beta-D-Glc pNAc-(1-->6)]-beta-D-Gal p-(1-->4)-D-Glc (lacto-N-novotetraose) and characterized by one- and two-dimensional NMR spectroscopy at 600 MHz.