Lipase-catalyzed synthesis of glucose fatty acid ester using ionic liquids mixtures

Novozym 435-catalyzed synthesis of 6-O-lauroyl-D-glucose in ionic liquids (ILs) was investigated. The highest lipase activity was obtained in water-miscible [Bmim][TfO] which can dissolve high concentration of glucose, while the highest stability of lipase was shown in hydrophobic [Bmim][Tf2N]. The optimal activity and stability of lipase could be obtained in [Bmim][TfO] and [Bmim][Tf2N] mixture (1:1, v/v). Specifically, the activity of lipase was increased from 1.1 to 2.9 mu mol min(-1) g(-1) by using supersaturated glucose solution in this mixture, compared with reaction using saturated solution. After 5 times reuse of lipase, 86% of initial activity was remained in this mixture, while the residual activity in pure [Bmim][TfO] was 36%. Therefore, the productivity obtained by using ILs mixtures was higher than those in pure ILs. (C) 2007 Elsevier B.V. All rights reserved.