Enzyme and Microbial Technology, Vol.25, No.3-5, 303-309, 1999
Kinetic resolution of 1-phenyl ethanol with high enantioselectivity with native and immobilized lipase in organic solvents
The effect of immobilization on activity, stability, and enantioselectivity of a Mucor miehei lipase for the kinetic resolution of 1-phenyl ethanol with vinyl propionate in organic solvents was studied. The native enzyme had a higher degree of purification as compared with previous preparations available. It had an initial esterification activity of 12 mu mol/min per g in hexane. Enantioselectivity exceeded 200, corresponding with an enantiomeric excess above 99%, for both phenyl ethanol and phenylethyl propionate at 50% conversion. Preincubation at 50 degrees C, or with phenyl ethanol, led, then applied at 25 degrees C, to an activity increase of 26% and 50%, respectively. The lipase was entrapped with no success in alginate and with good results in photo-crosslinkable resins of the hydrophilic type ENT 1000. The immobilized enzyme retained 25% esterification activity of the native enzyme and the enantioselectivity exceeded 200. The entrapped enzyme was successfully applied in a packed-bed reactor for 72 days of continuous resolution of enantiomerically pure 1-phenyl ethanol. After 15 days of adaptation, a productivity of 2.2 g/l/h was reached, which was more than one magnitude higher than could be expected from the activity data.
Keywords:SECONDARY ALCOHOLS;NONAQUEOUS MEDIA;BIOCATALYSTS;WATER;PREDICTION;DIFFUSION;ANHYDRIDE;ENZYMES