[目的]探索制备D-鸟氨酸盐酸盐的新方法.[方法] 采用L-鸟氨酸(L-Orn)为消旋反应原料,经消旋反应得到DL-Orn,然后利用蜂房哈夫尼菌AS1.1009中的赖氨酸脱羧酶进行DL-Orn酶法转化,可同时获得D-Orn和腐胺,并以此作为生物转化底物,考察了在水杨醛催化下,不同浓度NaOH水溶液对L-Orn消旋率和溶液中鸟氨酸总含量的影响.[结果] 通过化学酶法制备的D-鸟氨酸盐酸盐,收率为46.1%.确定在回流条件下使用1.0 mol/L氢氧化钠水溶液,用0.10摩尔比的水杨醛催化L-鸟氨酸在3 h内可生成DL-鸟氨酸.对生物转化中赖氨酸脱羧酶性质的研究表明,添加5 mmol/L的Fe2+ 可将比酶活提高为6 717 U.在此优化条件下,D-鸟氨酸可完全降解,最佳生物转化时间为16 h.[结论] 该研究为制备D-鸟氨酸提供了一种新的方法.%[Objective]The purpose was to explore the new method of preparing D-ornithine hydrochloride. [Method] With L-Ornithine (L-Orn) as the raw material for racemization reaction, DL-Orn was obtained through the racemization reaction, and then DL-Orn and putrescine was produced by means of biotransformation of DL-ornithine with lysine decarboxylase in Hafnia alvei AS1.1009 at same time, with which as the substrate of biotransformation, the effect of different concn. of NaOH water solution on DL-Orn rate and total amount of ornithine in the solution were investigated under salicylaldehyde catalysis. [Result] The D-ornithine hydrochloride prepared with chemoenzymatic method had yield of 46.1%. It was confirmed that in the water solution with 1.0 mol/L NaOH under return flow conditions, D-ornithine could be produced in the reaction process of racemizing L-ornithine by using 0.10 molar equivalent of salicylaldehyde within 3 h. The study on the character of lysine decarboxylase in biotransformation showed that adding 5 mmol/L Fe2+ ion could increase the specific activity up to 6 717 U. Under the optimization conditions, L-ornithine could be completely degraded by the decarboxylase, with the optimum time for biotransformation of 16 h. [Conclusion] This study peocided a new method for preparing D-ornithine.
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