摘要
以含离子液体共溶剂体系为反应介质,采用脂肪酶Novozym 435生物拆分2,2-二甲基环丙烷甲酸乙酯(DMCPE)制备S-(+)-2,2-二甲基环丙烷甲酸(S-(+)-DMCPA).研究表明:Novozym435在含离子液体[BMIM]OTF体系中的催化活性和立体选择性最好.通过对离子液体体积分数、缓冲液pH值、底物浓度及反应时间等因素的考察,确定最佳反应条件:[BMIM]OTF体积分数6%,Novozym 435用量16g/L,DMCPE浓度100mmol/L,缓冲液pH 7.2,30℃,反应52h.在优化的条件下,产率达47.4%,ee值为97.4%.考察了脂肪酶Novozym 435的重复利用情况,结果发现:脂肪酶可重复使用4次.与水相拆分相比,采用含亲水性离子液体[BMIM]OTF共溶剂体系进行DMCPE的生物拆分,底物浓度可由65mmol/L提高到100mmol/L,反应时间缩短12h,有效地提高了反应效率.
Enzymatic resolution of ethyl-2, 2-dimethylcyclopropanecarboxylate （DMCPE） to S-（＋）-2, 2-dimethylcyclopropanecarboxylic acid （S-（＋）-DMCPA） catalyzed by lipase Nov0zym 435 was performed in an ionic liquid-containing system. Among the seven ionic liquids investigated, [BMIM]OTF showed the best activity and enantioselectivity. Some key reaction parameters, such as [BMIM]OTF concentration, pH, substrate concentration and reaction time were investigated, respectively. The optimum conditions for the preparation of S-（＋）-DMCPA were found to be as follows： 6% [BMIM]OTF, 16 g/L Novozym 435, 100 mmol/L DMCPE, pH 7.2, at 30 ℃ for 52 h. Under above optimal conditions, the best yield of 47.4% was obtained with the ee value of 97.4%. The biocatalytic activity of Novozym 435 was found to be relatively stable in an ionic liquid-containing system after being repeatedly used for four batches. The results demonstrate that the enzymatic resolution is more efficient in an ionic liquid-containing system than that in the phosphate buffer solution, the substrate concentration increased from 65 mmol/L to 100 mmol/L and the reaction time was shortened by 12 h.
出处
《浙江工业大学学报》
CAS
2013年第4期409-413,435,共6页
Journal of Zhejiang University of Technology
基金
国家自然科学基金资助项目(21076193)
浙江省科技厅重大科技攻关项目(2010C11040)
浙江省公益性技术应用研究计划项目(2011C33005)
