Process for the isolation of L-amino acids

US4827029A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Axel Kleemann · Hanau, DE
• Kurt Klostermann
• Wolfgang Leuchtenberger
• Rudi E. Moerck · Sanford, US
• Michael Karrenbauer · Radolfzell, DE

Key dates

• Filing date: Jan 21, 1988
• Grant date: May 2, 1989
• Expiry date: Jan 21, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C12P13/04
• WIPO field: Biotechnology
• WIPO sector: Chemistry

Abstract

L-amino acids present in cleavage solutions obtained in the acylase-catalyzed cleavage of N-acetyl-D,L-amino acids are isolated by use of a strongly acidic ion exchanger in H+ form. First, the mother liquor from a previous treatment cycle is fed to the ion exchanger, and then the cleavage solution and finally the wash water and the discharge from the ion exchanger which is pH-controlled is analyzed into an "effluent water fraction", an "N-acetyl-D-amino acid fraction" and an "L-amino acid fraction". The last fraction is adjusted by addition of fresh cleavage solution to a pH of between 4.0 and 6.0, and from the mixture which is thus obtained the L-amino acid is isolated by crystallization. The mother liquor which is obtained is recycled back into a subsequent treatment cycle.