用嗜热菌蛋白酶催化合成天冬甜精并同时进行DL-苯丙氨酸甲酯的光学拆分

以DL-苯丙氨酸甲酯作原料,利用嗜热菌蛋白酶和固定化嗜热菌蛋白酶催化合成了天冬甜精,经拆分得到D-苯丙氨酸甲酯。实验结果表明,不仅天冬甜精产率高,而且D-苯丙氨酸甲酯的回收率好,光学纯度高。

Simultaneous Synthesis of Aspartame and Optical Resolution of DL-Phe-OMe by Thermolysin

Using DL-phenylalanine methyl ester as reaction substrate instead of L-phenylalanine methyl ester, aspartame was synthesized in good yield by the catalysis of either thermolysin or the immobilized thermolysin. In addition, optical resolution of DL-phenylalanine methyl ester could be achieved simultaneously in this reaction process. Costly D-phenylalanine methyl ester was also obtained in high yield. In the enzymatic reaction, the effects of reaction conditions on the synthetic yield were studied. Reuse of the immobilized thermolysin was also investigated. The experimental results showed that the immobilized thermolysin has better reuse ability. In comparison with the reaction catalyzed by thermolysin, the reaction catalyzed by the immobilized thermolysin required a longer time, and tile yield is slightly lower. The present work provided an economic and practical method for the preparation of aspartame.