Enzyme Catalysed Synthesis in Ambient Temperature Ionic Liquids

Abstract

The activity of three different lipases, a glycosidase and a protease in ionic liquids has been studied. Ambient temperature ionic liquids are a new class of solvents that are nonvolatile and nonflammable and thus an interesting alternative to classical organic solvents. Monitoring the synthesis of a simple ester, all lipases were found to exhibit both excellent activity and stability in the non-polar ionic liquid 1-butyl-3-methylimidazohum hexaflurophosphate ([bmin][PF6], 1). Furthermore, β-galactosidase from E. coli and the Subtilisin protease SavinaseTM were both found to exhibit a hydrolytic activity in a 50% aqueous solution of the water-miscible ionic liquid 1-butyl-3-methyhmidazoUum tetra-fluoroborate ([bmin][BF4], 2) comparable to the activity observed in 50% aqueous solutions of ethanol and acetonitrile.