Biocatalysis in Ionic Liquids

Abstract

In the context of green chemistry and white biotechnology, ionic liquids, solvents composed only by asymmetric cations and anions, have been highlighted as alternatives to molecular solvents, mainly because of their non-volatility at room temperature, huge liquidus range and tunable physicochemical properties. With these properties, ionic liquids can be utilized as potential new media for biocatalytic reactions involving enzymatic and whole-cell systems. This chapter summarizes recent studies which apply ionic liquids to these biotransformations. In enzymatic catalysis, they have been applied as pure solvents or co-solvents, and can improve the selectivity, yield, substrate solubility and catalyst stability. Similarly, ionic liquids have been applied in whole-cell processes as co-solvents in monophasic or biphasic systems to promote substrate solubility, and decrease the toxic effects of substrates and products on microorganisms. Here, will be reported systematically studies of ionic liquids and lipases, proteases, esterases and glycosidases, among other enzymes, showing their diverse applications, and results on the activity and stability of the biocatalysts. Furthermore, recent studies using ionic liquids in various biotransformations with microorganisms, mainly in asymmetric reduction of ketones will be reported.