Catalytic activity and enantioselectivity in organic solvent of lipase immobilized on ODS-sugar ester

Three lipases were immobilized on ODS-Sugar, which was prepared by coating sucrose mono-stearate (sugar ester) on octadecyl silica gel (ODS-silica). T he enantioselective esterification of (R)- or (S)-1-phenylethanol with alip hatic acid was studied in the presence of immobilized lipase (ODS- Sugar(-) Lipase) in organic solvents by varying the lipase origin, reaction media a nd substrate structures. The ODS-Sugar-Lipase (LPL-311) showed both high ca talytic activity and enantioselectivity for the esterification of (R)-1-phe nylethanol with long-chain aliphatic acid in dry iso-octane. On the other h and, the ODS-Sugar-Lipase (M) showed both a high catalytic activity and ena ntioselectivity for the esterification of (S)-ibuprofen with hexanol in dry iso-octane. The enzymatic activity of lipases in organic media was remarka bly enhanced by immobilization with the sugar ester. The reaction rates of the immobilized lipases were increased by around 100 similar to 200-fold co mpared to that of the native lipases. The activity of the immobilized lipas es has been retained for at feast one month in refrigerator. The ODS-Sugar- Lipase showed greater activity for ester synthesis than other systems, such as the PEG-grafted lipase and the powder dispersion system. We believe tha t the ODS-Sugar adsorbed enzyme system can be widely applicable to other en zymes whose substrates are lipophilic.