Quantitative Analysis of Sugars in Plant Extracts by Ion-exchange Chromatography,with Special Reference to the Examination of Conditions for Preparing the Sample Sugar Solutions

Critical examinations were made on the conditions for preparing the sugar solutions to be analyzed by ion-exchange chromatography of sugar-borate complexes by the method of Khym and Zill. A procedure was proposed which gave the best recovery of sugars with minimum hydrolysis of sucrose. By means of this procedure, sugar solutions were prepared from potato tubers which had been stored at a high (30°C) or low temperature (6°C). Results of the chromatographic separation and determination of component sugars showed that main sugars present in potato tubers were sucrose, glucose, and fructose. Maltose and pentoses could not be detected. The contents of sucrose, glucose, and especially, fructose were far greater in potatoes stored at a low temperature than in those stored at a high temperature.