| 摘要 |
<p>PURPOSE:To obtain a purified material of L-tryptophan, etc., produced by an enzyme and having low indole content by extracting an unreacted raw material in a material produced by the enzyme with carbon dioxide kept in a state of liquid or supercritical gas and separating the unreacted raw material such as crude L-tryptophan. CONSTITUTION:Indole is subjected to enzymatic condensation reaction with L-serine and produced L-tryptophan water solution is directly concentrated and deposited to collect a crude L-tryptophan, which is charged into an extracting device 1 and pressure of automatic pressure control equipment 4 is set to 200kg/cm<2> and carbon dioxide kept to a state of liquid or supercritical gas from a liquefied carbonic acid gas bomb 2 is fed from a liquefied carbondioxide gas bomb 2 to the extracting vessel 1 by a feed liquid pump 3 and an organic solvent for entrainer is fed from a reagent bottle 9 to the extracting vessel 1 by a feed liquid pump 8 to carry out extraction treatment of the crude tryptophan and the extraction treated crude L-tryptophan is moved to a separator 6, where pressure is reduced up to atmospheric pressure to deposit indole and the deposited indole is removed and pressure in the extracting device 1 is returned to atmospheric pressure to provide the purified L-tryptophan of material produced by the enzyme.</p> |
