Analysis of Monosaccharides in Bovine,caprine and Ovine #kappa#-Casein Macropeptide by Gas chromatography

摘要

Monosaccharides present in #kappa#-casein macropeptide (CMP) from bovine, ovine and caprine milks have been determined by gas chromatography after acid hydrolysis with trifluoroacetic acid (TFA) or methanolysis with HCI-methanol. The method has been evaluated for repeatability and recovery using myo-inositol as internal standard with satisfactory results. Galactose, N-acetyl-galactosamine and neuraminic acid were found in the #kappa#-casein macropeptides from the three species and similar levels of galactose and N-acetyl-galactosamine were found after treatment with TFA and HCI-methanol. Bovine CMP exhibited the highest level of glycosylation. In general, the main component of the carbohydrate fraction was neurainic acid. The method is suitable for the analysis of monosaccharides in CMP.