Kinetic resolution of (R,S)-α-tetralol catalyzed by crosslinked Candida antarctica lipase B enzyme supported on mesocellular foam: a nanoscale enzyme reactor approach

Publication date: Available online 22 June 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Manoj P. Kamble, Somnath D. Shinde, Ganapati D. Yadav Nanoscale enzyme reactors (NERs) of C. antarctica lipase B (CALB) were prepared by enzyme adsorption on to mesoporous microcellular foam (MCF) followed by enzyme crosslinking within the pores. NERs effectively prevents enzyme leaching and consequently improves thermal stability. MCF has a unique pore structure that is composed of spherical 40nm sized mesocellular pores connected by 5–20nm sized mesoporous window. These smaller connecting pores prevent the leaching of enzyme aggregates, hence the ‘ship-in-a-bottle’ description. The synthesised MCF was characterized using FT-IR, scanning electron microscopy (SEM) and N2 adsorption. CALB/MCF was then subsequently used for the enantioselective esterification of (R,S)-α-tetralol and vinyl acetate. The various reaction kinetic parameters affecting the initial rate, conversion and enantiomeric excess were investigated to establish enzyme kinetics and mechanism. CALB/MCF enatioselectively catalysed the esterification of (R,S)-α-tetralol with conversion of 43.7%, ees 75.5% eep>99.9% and enantiomeric ratio (E) grater than 100 at 50°C in 24h. The rate constants clearly show that reaction obeys Ping Pong bi-bi mechanism with inhibition by vinyl acetate. The experimental and simulated rates match very well showing the validity of the proposed kinetic m...
Source: Journal of Molecular Catalysis B: Enzymatic - Category: Biochemistry Source Type: research