GLYCOSYL UREIDES IN RUMINANT NUTRITION .1. PREPARATION AND ESTIMATION OF LACTOSYL UREA AND OTHER GLYCOSYL UREIDES

Glucosyl urea, lactosyl urea and galactosyl urea were prepared from pure sugars and urea. Their purity was confirmed by determination of their melting points, specific rotations and by mass spectrometry. Using whey as a lactose source, a range of conditions were examined for the preparation of lactosyl urea on a laboratory scale. Yields of 60% were achieved when lactose and urea (molar ratio, urea:lactose 0:6) were reacted for 15 h in sulfuric acid at pH 2.0 and a temperature of 70.degree. C. Methods of detection and estimation of all 3 ureides in whey preparations and ruminant digesta samples were developed. Two quantitative methods, one involving acid-hydrolysis, the other ion-exchange chromatography, were used. The latter method enabled determination of individual quantities of ureides in mixtures.