Increased stability of an esterase from Bacillus stearothermophilus in ionic liquids as compared to organic solvents

Ionic liquids in biotechnology: applications and perspectives for biotransformations

“…Increased stability was reported for Bacillus stearothermophilus esterase immobilised on celite in [BMIM] [PF 6 ] compared to MTBE and hexane both at a W =0.11; half life in MTBE and hexane was determined with 80 h and 8 h, respectively, no inactivation in IL was observed within 240 h (Persson and Bornscheuer 2005). The authors attribute the stabilisation to electrostatic interactions between the IL and the enzyme.…”

“…The authors attribute the stabilisation to electrostatic interactions between the IL and the enzyme. Candida rugosa lipase (CRL) was recycled five times in [BMIM] [PF 6 ], [OMIM] [PF 6 ], as well as in organic solvents (toluene and hexane) with decreases in activity of 5%, 8% and 50%, respectively, and a decrease of 15% for the enantioselectivity in IL as compared to more than 50% for both tested organic solvents (Persson and Bornscheuer 2005). Later, storage [MeSO 4 ] which was confirmed by minimal changes in the infrared spectrum of the dissolved enzyme (Rantwijk et al 2006).…”

Application of Room Temperature Ionic Liquids in Electrochemical Sensors and Biosensors

“…The difference between the potentials of their anodic (E a ) and cathodic (E c ) decomposition is usually greater than 3 V (Ohno, 2005), while for aqueous electrolytes is about 1.2 V. Because of this remarkable property of ionic liquids, they find wide use in electrochemical biosensors. Recently, some authors have reported increased stability of enzymes in ILs compared with stability in some organic solvents (Lozano et al, 2001;Laszio, et al 2002;Park, S. & Kazlauskas, 2003;Persson & Bornscheuer, 2003). ILs were also found to act as agents to stabilize proteins effectively at high temperatures (Baker et al, 2004 [PF 6 ]) was widely used in construction of electrochemical biosensors due to their very good biocompatibility.…”

Fluorescence and CD spectroscopic analysis of the α‐chymotrypsin stabilization by the ionic liquid, 1‐ethyl‐3‐methylimidazolium bis[(trifluoromethyl)sulfonyl]amide

“…as novel media for enzyme-catalyzed transformations has recently attracted considerable attention, and could be considered an important axis for development of green chemistry in the near future (van Rantwijk et al, 2003). Indeed, some ionic liquids (ILs) have been shown to be excellent nonaqueous media for enzyme-catalyzed reactions, not only because the enzymes display a high level of activity and stereoselectivity for many different chemical transformations, e.g., aliphatic ester synthesis (Lozano et al, 2003), the kinetic resolution of racemic alcohols (Schöfer et al, 2001;Lozano et al, 2004;Noël et al, 2004), carbohydrate ester synthesis (Park and Kazlauskas, 2001), and polymer synthesis (Nara et al, 2003), but also because of their important stabilizing effect on enzymes (up to 2,300-fold increased half-life time with respect to classical organic solvents) (Lozano et al, 2001a,b;Persson and Bornscheuer, 2003).…”