RECOVERY METHOD OF L-THREONINE FROM FERMENTATION BROTH BY ELECTRODIALYSIS

摘要

PURPOSE: Recovery method of L-threonine by weak anion exchange resin without desalting, adsorption and elution steps after electrodialysis or direct electrodialysis with changed L-threonine is provided. CONSTITUTION: The invention is disclosed recovery methods of L-threonine comprised steps of a) removing of cell mass by centrifugation or filtration, b) adjusting pH of broth around 5.0-6.5 at isoelectric point of L-threonine, c) putting into dilution chamber(Dn) for desalting, d) collecting L-threonine solution from dilution chamber when electroconductivity of solution reaches under 10 mS/cm, e) passing into weak anion exchange column, and f) concentration and crystallization. The other method only using electrodialysis comprises the steps of: a) removing of cell mass, b) adjusting pH of broth at 2.0, c) putting into dilution chamber(Dn), d) collecting L-threonine solution from concentration chambers(Cn) and e) concentration and crystallization. These methods produce 98 % pure L-threonine and recovery yield is over 94 %.