Simultaneous saccharification and isomerization by immobilized glucoamylase and glucose isomerase

Glucoamylase and glucose isomerase, which are often used in industry to produce high‐fructose corn syrup, were immobilized on porous anilino‐sulfonic polystyrene beads and porous triethanolamine methyl polystyrene beads, respectively. These charged supports altered the pH profiles of the two enzymes such that it was possible to carry out simultaneous saccharification and isomerization at pH 6.5 or pH 7.5 using immobilized glucoamylase and immobilized glucose isomerase. This process is very difficult to accomplish with soluble glucoamylase and glucose isomerase because of the large difference in the pH profiles of the two enzymes in their soluble form.