摘要：

The supported biocatalysis was prepared with the highly active yeast double-layer immobilized by alginate as the inner layer and alginate improved by polyvinyl alcohol with good mechanical property as outer layer,which was applied in the asymmetric catalytic hydrogenation of COBE(ethyl 4-cloro-3-oxobutyrate) in the biphase of phosphate buffer solution for the preparation of(S)-CHBE.The best converting yield was 94.2% and the best e.e% was 98% under the optimal concentration 170mmol/L and flow rate 125mL/h.Comparing with the free yeast,the converting yield increased 3%,the concentration of substrate increased 100%.Comparing with the one layer immobilized yeast,the enantioselectivity excess increased 8%.The continuous experiment showed that double layer immobilized yeast can be recycled to use in 5 days without significant decrease in the bioreduction of COBE.

展开