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

摘要

The beta-glucosidase catalysed synthesis of butylglucoside through the condensation of glucose and butanol was carried out in monophasic and biphasic systems. Water was indispensable for the enzyme activity. In the case of the monophasic system, product concentration increased with the increase of water content, but at high levels of water the equilibrium shifted towards hydrolysis and therefore the butylglucoside concentration decreased. An optimal water content of about 8-13% (v/v) was found. However, in the case of biphasic system, the increase of the aqueous/butanol phase ratio (v/v) was accompanied by a decrease of the butylglucoside concentration. An analysis of the causes of the equilibrium shift is given.