| 摘要 |
<p>alpha -Hydroxycarboxylic acids are continuously converted into the corresponding optically active alpha - aminocarboxylic acids. The conversion is carried out in a membrane reactor in the presence of nicotinamide-adenine dinucleotide increased in molecular weight by bonding to a water soluble high molecular weight material, a dehydrogenase specific for the alpha -hydroxycarboxylic acid, a dehydrogenase specific for the corresponding alpha -amino-carboxylic acid and ammonium ions. There is continuously supplied to the membrane reactor an aqueous solution of the alpha -hydroxycarboxylic acid to be reacted, a substantially lesser amount of the corresponding alpha -ketocarboxy lic acid, and an amount of ammonium ion at least equivalent to the alpha -hydroxycarboxylic acid to be reacted. There is maintained over the membrane a difference in pressure 1 and 15 bar. Behind the membrane, there is continuously drawn off a filtrate stream containing the alpha -aminocarboxylic acid formed.</p> |
