【摘要】 研究了米曲霉3042细胞催化N-乙酰-D,L-3-三甲基硅丙氨酸不对称水解反应,系统探讨了振荡速度、缓冲液浓度、反应温度和pH值对反应速度和反应选择性的影响。结果表明,上述因素对N-乙酰-D,L-3-三甲基硅丙氨酸不对称水解反应速率和反应选择性均有较显著的影响。振荡速度以170r?min?1为宜,适宜的磷酸盐缓冲液浓度为0.10mol?L?1,合适pH值为7.0,合适反应温度为50℃。在该优化反应条件下,以1g游离的米曲霉3042菌丝体催化10mmol?L?1N-乙酰-D,L-3-三甲基硅丙氨酸不对称水解,反应初速度为0.42mmol?L?1·h?1,反应79h,底物转化率为49.5%,产物L-三甲基硅丙氨酸的e.e.为92.7%。更多还原

【Abstract】 Optically active L-3-(trimethylsilyl)-alanine is an unnatural silicon-containing amino acid with special bioactivity. The preparation of L-3-(trimethylsilyl)-alanine by asymmertric hydrolysis of N-acetyl-D, L-3-(trimethylsilyl)-alanine catalyzed by free Aspergillus oryzae 3042 cells was studied, and the effects of the shaking speed, phosphate buffer concentration, pH value and reaction temperature on the reaction rate and the enantioselectivity were systematically investigated. It is found that all the factors mentioned above have important effects on the reaction. The optimal values of the shaking speed, phosphate buffer concentration, pH value and reaction temperature are 170 r?min?1, 0.10 mol?L?1, 7.0 and 50℃, respectively. When 10 mmol?L?1 N-acetyl-D,L-3-(trimethylsilyl)-alanine is hydrolyzed with 1g free Aspergillus oryzae 3042 cells in a phosphate buffer solution, under the above mentioned proper operation conditions and with a reacting time of 79 h, a substrate conversion ratio of 49.5% could be achieved with a high product e.e. of 92.7%.更多还原