Catalysis of modified immobilized penicillin acylase in non-aqueous phase

In order to improve the activity and stability of penicillin acylase (PA), PA was co-assembled in mesocellular siliceous foams (MCFs) and used to hydrolyze penicillin in aqueous-organic medium. The effects of kind and volume fraction of organic solvent, addition of Dex 10 k on the thermal and operational stability of immobilized enzyme were investigated. In the experiment the specific activity of the modified PA in MCFs was 209.5 U/mg after adding Dex 10 k into the petroleum ether with volume fraction 20%. It is 196.2% of unmodified PA in MCFs in full aqueous medium. 71.5% of its initial activity was recovered over 25 repeated batch cycles in the petroleum ether with volume fraction 20%. The results show that the aqueous-petroleum ether two-phase medium is suitable for PA, and co-assembling Dex 10k into immobilized enzyme can enhance the catalytic activity and stability in the two-phase.