精氨酸酶转化生产D-精氨酸和L-鸟氨酸

以L-精氨酸为原料,经水杨醛催化消旋反应得到DL-精氨酸,在精氨酸酶的作用下,定向地将L-精氨酸转化为L-鸟氨酸和尿素,并经进一步分离纯化得到D-精氨酸和L-鸟氨酸盐酸盐。该文通过水杨醛对L-精氨酸进行消旋化,反应2.5 h,消旋率可达74.5%;同时,对L-精氨酸酶促反应条件进行了优化,结果表明,最佳反应条件为:37℃,pH=10,反应时间24 h,底物质量浓度40 g/L,酶质量浓度0.2 g/L,在该条件下转化率可达98.0%。经该法制备得到的产物D-精氨酸和L-鸟氨酸盐酸盐纯化后光学纯度可达99.0%。

Production of D-Arginine and L-Ornithine by Enzymatic Conversion of L-Arginine Amidinase

A practical method for the racemization of L-arginine and an enzymatic method for the optical resolution of DL-arginine by L-arginine amidinase have been developed.D-arginine and L-ornithine hydrochloride can be obtained after isolation and purification.Many factors affecting the racemization and enzymatic reaction were studied.The results show that the whole process of racemization by salicylic aldehyde can be completed within 2.5 h.The ratio of the racemization was as high as 74.5%,and the optimum conditions of the enzymatic conversion were:pH=10,37 ℃,40 g/L of substrate mass concentration and 0.2 g/L of L-arginine amidinase mass concentration.Under these conditions,the conversion of L-arginine can be reach 98.0%.The products were separated and purified on ion-exchange resin,and the optical purity of the products were 99.0%.