Facilitating enzymatic reactions by using ionic liquids: A mini review

Abstract

Over the past two decades, ionic liquids (ILs) have been widely used for enzymatic conversions of substratesespecially substrates that are insoluble in common organic solvents and waterresulting in high conversion rates, high selectivity, and improved enzyme stability, wherein the ILs are recoverable and recyclable. Compared with performance in first-generation ILs, researchers recently considerably improved the technological utility of enzymes in second-and third-generation ILs composed of enzyme-benign cations and anions. Use of upgraded ILs with enzymes offers further improved activity and stability compared with research studies in the past decade, rendering IL-assisted biocatalytic processes more environmentally and economically attractive. This short review briefly presents recent developments of enzymatic reactions in ILs. The review covers approaches for and modifications of enzymes and ILs within the past 2 years for improved enzymes performance in ILs.

Versatile Applications of the Ionic Liquid

“…The second category is binary ionic liquids. [2,14,[17][18]. MW irradiation method is used by Verma and Namboodiri to synthesize 1-alkyl-3-methylimidazolium halides (chloride and bromide) and dialkyl-3-methylimidazolium dihalides ILs with > 70% yield in less than 2 mins [19].…”

“…ILs are extensively used for enzymatic reactions of materials which are insoluble in water and common organic solvents. ILs facilitate several enzyme-catalyzed reactions with marvelous yields [14]. This review will discuss about the use of IL in the various fields of chemistry.…”

“…Support based ILs are used for air purification and IL based adsorbents removes the indoor pollutants [10,12]. ILs facilitate the enzymatic reactions [14]. ILs has also been applied as environmental friendly cutting fluid and sustainable corrosion inhibitors [9,11].…”

Enzyme entrapment, biocatalyst immobilization without covalent attachment

“…187,188 This tuning of the ionic liquid's properties makes ILs unique liquids for enzymes and biocatalysis, and the low volatility and flammability of ILs render them safer and less likely to damage biomaterials. 35,37,38,[189][190][191][192][193][194][195] Enzymes tend to degrade when stored in conventional aqueous and organic solvents, potentially limiting their widespread industrial applications in chemical synthesis. The reuse and recovery of biocatalysts is particularly challenging.…”

Applications of Ionic Liquids in Whole-Cell and Isolated Enzyme Biocatalysis

“…Ionic liquids have been observed to stabilize proteins in many studies. Useful information on enzyme stability and biocatalysis in ionic liquid media can also be found in recent reviews [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ].…”