Ionic liquids in biotransformations

The use of water as solvent in enzymatic reactions for years limited the field of application of enzymes in biocatalysis and the productivity of some processes, particularly those involving hydrophobic substrates. As a consequence, the applicability of catalysis in non-aqueous solvents has been tested and discussed and as a result, new reaction media have been suggested. The possibility of working with hydrophobic substances, the decrease in microbial contamination and reduction of side reactions are the main advantages related with the development of procedures in non-aqueous media. Organic solvents helped to reduce some problems such as the insolubility of hydrophobic compounds and propagation of radicals in aqueous solutions and proved to valid solvents for enzymes catalysis, in some cases offering benefits related with enzyme stability and selectivity. However, organic solvents exhibit known disadvantages such as human and environmental toxicity and high volatility that make their application in routine procedures difficult.

Replacement of organic solvents in enzyme mediated processes

Due to their particular characteristics, ILs have emerged as “green” substitutes of conventional organic solvents in enzymatic reactions, sometimes with remarkable results, offering new possibilities for the application of solvent engineering to biocatalytic reactions. Their specific properties such as nonflammability, nonvolatility and good chemical and thermal stability made them a safe alternative to conventional organic solvents.

Our research on this field has been focused on the study of enzymes involved on processes usually performed in non-aqueous media in order to evaluate the possibility of using ILs without significant prejudice of reactions yields.

Replacement of organic solvents in enzyme mediated processes

Due to their particular characteristics, ILs have emerged as “green” substitutes of conventional organic solvents in enzymatic reactions, sometimes with remarkable results, offering new possibilities for the application of solvent engineering to biocatalytic reactions. Their specific properties such as nonflammability, nonvolatility and good chemical and thermal stability made them a safe alternative to conventional organic solvents.

Our research on this field has been focused on the study of enzymes involved on processes usually performed in non-aqueous media in order to evaluate the possibility of using ILs without significant prejudice of reactions yields.

Considering the industrial processes catalyzed by enzymes in organic media the possibilities of research on this field are immense as our objective is the search for greener solvents with less impact than the conventional ones.

Incorporation in mixed micelles with conventional surfactants

There has been an increasing and particular interest on the issue of micelle formation mainly on alkylimidazolium ILs and considerable progress has been made in this field. Besides the possibility of self-assembly in solutions one must also consider their ability to act as modulators of the aggregative behaviour of classical surfactants either in mixed or reverse micelles, which opens novel and broad perspectives regarding their industrial application. This idea of micelles with tailored physico-chemical properties in ILs solutions is very promising and has already been considered economically convenient.

On this field our research resulted on the pioneering evaluation of the influence of mixed micelles of surfactant and IL on the activity of some enzymes (Ex: β-galactosidase, α-chymotrypsin) with industrial application. The increase of enzyme activity and stability in IL-surfactant micelles is a starting point to further studies with other enzymes involved in important biotechnological processes.