Optimization of Enzyme Loading and Other Parameters

The effect of enzyme loading on rate of the reaction and selectivity was examined at a pH of 7.8. In several relatively large-scale trials, we found that 0.10 to 0.15 mL of 5% enzyme solution per gram of substrate was sufficient to give a product with an ee of 99.5% within 8 hours. The results of a more systematic analysis of the effects of substrate concentration are shown in Tab. 5. 

The results presented above clearly indicate that the resolution of (R,S)-4 can be easily carried out using Bacillus lentus proteases. As has been mentioned before we chose Bacillus lentus protease-III for further development because of its efficacy and lower cost. Commercial formulations of this enzyme are stable and avail- 

Enzyme (mL) 1 Substrate (S) mL Enzyme/g substrate Ester concn. (%) Reaction time (V ee of ester m 

Temperature was maintained at 25 °C and reaction allowed to proceed until the desired was reached. a) Protein concentration is approximately 5% in the enzyme solution. optical purity 

Reaction conditions pH = 7.0. 0.3 mL B. lentus protease-I, 10% substrate loading, 0.3 M phosphate buffer with  

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