Synthesis of alkyl glycosides through β-glucosidase-catalyzed condensation in an aqueous–organic biphasic system and estimation of the equilibrium constants for their formation

Hexyl, heptyl and octyl glucosides, galactosides and fucosides were separately synthesized through the β-glucosidase-catalyzed condensation of glucose, galactose and fucose with the corresponding alcohols in an aqueous–organic biphasic system, where one of the substrates, alcohol, was the organic phase, at various volume ratios. An equation for predicting the equilibrium yield of an alkyl glycoside was proposed, and the parameters involved in the equation were experimentally determined. The equilibrium constant K for the alkyl glycoside formation was then evaluated. Although the K value slightly depended on both the saccharide moiety and the alkyl chain length, it was approximately 2.