The analysis of relationships between structure and retention time in gas liquid chromatography of pentoses and hexoses leads to the formulation of following rule: the per-O-trimethylsilyl derivatives of aldoses stereoisomers with conformational stability, identical ring form and the same number of substituted OH groups are longer retained on polar columns when the equatorial substituents are more numerous and are located nearer to the anomeric carbon.
Different conditions for the acid hydrolysis of carbohydrate-containing substances, e. g. glycoproteins or mucopolysaccharides of body fluids were tested. The errors arising during quantitative analysis of hydrolysate components are discussed. Hydrolysis correction factors can be used in order to obtain the original sugar composition of the specimen. The authors tried to develop a procedure generally appliable to the calculation of such factors as a function of release and decomposition of sugars under standard acid hydrolysis conditions (3 ɴ HCl for 3 h at 100 °C, sealed tubes, N2). The experiments were performed with lyophilisates of non-dialyzable substances of gastric juice and with the respective free sugars.
Decomposition rates of sugars in the presence of a corresponding hydrolysate of juice proteins were studied under various conditions; the rate curves showed a nearly logarithmical evolution, their slope expressing the acid resistance of the sugar in the given case. Basing on these rates and on the concentration curves of sugars in the native juice hydrolysed under the same conditions, an empirical formula was developed whose different mathematical aspects are subsequently analyzed.