摘要
L-赖氨酸经化学消旋反应后,应用蜂房哈夫尼菌(Hafnia alvei)AS1.1009对其进行生物转化,可制备D-赖氨酸,理论收率为56.6%。确定了在100℃下,以1.0mol/L氢氧化钠水溶液,用0.10摩尔比的水杨醛催化L-赖氨酸在4h内消旋,反应活化能为62187.86J/mol;对生物转化中赖氨酸脱羧酶性质研究结果表明该酶最适pH为8.0,最适温度为37℃,吐温-80质量浓度0.5g/L,菌体质量浓度10g/L,底物质量浓度为30g/L时,最高比酶活为3840U。在此优化条件下转化时间为12h。
After L-lysine racemized the D, L-lysine crystals was treated as substrate with Hafinia alvei AS1. 1009 intact cells as biocatalysts for getting crystalline D-lysine with a yield of 56.6% from the reactant mixture after the simple purification. In the presence of 0.10 molar equivalent of Salicylaldehyde the whole process of L-lysine racemization can be completed within 4 h in a medium of 1.0 mol/L of NaOH under 100℃ .The activation energy of the processes was 62 187.86 J/mol.The characteristics of Hafnia alvei AS1. 1009 decarboxylase were studied. Under the conditions as follows： pH 8.0, temperature 37℃, cell concentration 10 g/L, tween-80 0.5 g/L, substrate concentration 30 g/L, the specific activity was up to 3 840 U. L-lysine can be completely degraded by the decarboxylase for 12 h under the optimal conditions.
出处
《现代化工》
EI
CAS
CSCD
北大核心
2007年第5期32-34,共3页
Modern Chemical Industry
基金
国家技术创新基金(02CJ-13-01-16)资助项目
关键词
D-赖氨酸
脱羧酶
消旋
生物转化
D-lysine
decarboxylase
racemization
biotransformation
