Dosage comparatif des produits issus de la dégradation alcaline des hexoses

Abstract

The mixture of hexoses and carboxylic acids produced by alkaline degradation of fructose was analyzed quantitatively by high-performance liquid chromatography. A pulsed amperometric detector with two Carbopac Dionex columns in series was employed in the assay of sugars (glucose, fructose, mannose, sorbose, and psicose), while a conductimeter with an HPICE AS1 Dionex column was employed for carboxylic acids (lactic, glyceric, glycolic, formic, and acetic). This sensitive and reproducible method obviated sample pretreatment. The results were compared with those of enzymatic assays and HPLC determinations using Biorad HPX87C and HPX87P columns in series for the sugars, and an Interaction ORH 801 column for the carboxylic acids. The behaviour of fructose, glucose, and mannose in alkaline medium was compared. Keywords: hexoses, polyhydroxylic acids, isomerization, alkaline degradation, high-performance ionic liquid chromatography.