earticle

영어

Subtilisin Carlsberg (SC) from Bacillus licheniformis was immobilized and stabilized in magnetically-separable mesocellular silica (Mag-MSU-F), and used for the model synthetic reaction in an organic solvent. The SC stabilization was based on a ship-in-a-bottle approach, which consists of enzyme adsorption and crosslinking steps. In mesoporous silica with a bottle-neck pore structure, the crosslinked enzymes in larger mesocellular pores did not leach out through smaller window mesopores. As a result, crosslinked enzymes retained more than 66% of the initial activity even after ten times of reuse and for more than 15 days under rigorous shaking condition. On the other hand, free and adsorbed SC showed less than 1% and 2.8% of initial activities, respectively, under the same condition. Crosslinked SC were employed for the transesterification reaction of N-Ac-Phenylalanine ethyl ester with n-propanol in isooctane. Especially, the use of magnetically-separable mesoporous silica allowed for easy separation and recycled uses of immobilized enzymes, which is important for the practical applications of enzymes in fields.