DETERMINATION OF MONOSACCHARIDES IN CELLULOSIC HYDROLYZATES USING IMMOBILIZED PYRANOSE OXIDASE IN A CONTINUOUS AMPEROMETRIC ANALYZER

The pyranoses, glucose, xylose, and galactose, were determined In a flow injection system using an immobilized enzyme reactor with pyranose oxidase (EC 1.1.3.10). Oxygen consumed by the oxidation was measured with an amperometric electrode (Clark type). The electrode response, after partial transfer of the sample through a dialysis membrane, was linear between 0.6-30 mM glucose, 1.0-50 mM xylose, and 2.0-100 mM galactose with an accuracy of ±7.0%. The influence of the matrix of a crude medium, spent sulfite liquor, a pyranose-containing by product from the pulp industry, was investigated and found negligible with respect to sensitivity and stability, at least up to 2000 measurement cycles of the analytical system. Application of the system to continuous monitoring of ethanolic fermentation was also demonstrated. © 1990, American Chemical Society. All rights reserved.