Enzymatic-catalyzed synthesis of alkylglycosides in monophasic and biphasic systems. II. The reverse hydrolysis reaction

The beta-glucosidase catalyzed synthesis of butylglucoside through the cond ensation of glucose and butanol was carried out in monophasic and biphasic systems. Water was indispensable for the enzyme activity. In the case of th e monophasic system, product concentration increased with the increase of w ater content, but at high levels of water the equilibrium shifted towards h ydrolysis and therefore the butylglucoside concentration decreased. An opti mal water content of about 8-13% (v/v) was found. However, in the case of b iphasic system, the increase of the aqueous/butanol phase ratio (v/v) was a ccompanied by a decrease of the butylglucoside concentration. An analysis o f the causes of the equilibrium shift is given. (C) 1999 Elsevier Science B .V. All rights reserved.