| 摘要 |
A process for production of L-aspartic acid comprising (1) contacting (A) an enzyme-containing material having maleate isomerase activity and aspartase activity, or (B) an enzyme-containing material having maleate isomerase activity and an enzyme-containing material having aspartase activity, with an aqueous substrate solution containing maleic acid and ammonia, and/or mono or di-ammonium maleate, to form L-ammonium aspartate, in a reaction solution, (2) adding the reaction solution to an aqueous solution of maleic acid or maleic anhydride at a controlled rate to crystallize L-aspartic acid in a mother liquor, and (3) recovering the L-aspartic acid from the mother liquor, and (4) optionally recycling said mother liquor as a substrate solution for further reaction with said enzyme containing material of Step 1 and (5) optionally adding alkali such as ammonia to said mother liquor before, during, or after recycle. |
