用循环式生物反应器酶法生产L-丙氨酸

The Recycling Biotransformation Reaction System for Production of L-Alanine Using Immobilized Cells

用固定化德阿昆合假单孢 (Pseudomonas dacunhae)菌体的 L-天门冬氨酸 - β-脱羧酶 ,在新设计的生物反应器中转化 L-天门冬氨酸生成 L-丙氨酸。该反应器能不断缓慢溶解固体 L-天门冬氨酸 ,使反应系统的 p H和底物浓度维持恒定。用 80 g固定化菌体为酶源 ,在 6 9h内能将4 .2 kg L-天门冬氨酸全部转化成 L-丙氨酸 ,且仅消耗较少的 PLP和氨水。

A new bioreactor was designed for enzyme conversion of L asp to L ala by L aspartate β decarboxylase locating in immobilized Pseudmonas dacunhae CPU210001 cells. The pH value and substrate concentration of the biotransformation reaction system can automatically been maintained by dissolving solid L asp continuously. 4.2kg L asp was effectly been converted into L ala in the bioreactor containning 80g wet cells immobilized in carrageenan in 69 hours, with less pyridoxal 5′ phosphate and ammonia consumption than conventional bioreactor.