Gumel Ahmad Mohammed, Annuar M S M
Department of Biotechnology and Microbiology, Faculty of Science, Federal University, Dutse, 7156, Jigawa State, Nigeria.
Faculty of Science, Institute of Biological Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia.
3 Biotech. 2016 Jun;6(1):24. doi: 10.1007/s13205-015-0355-9. Epub 2016 Jan 11.
Enzymatic catalysis is considered to be among the most environmental friendly processes for the synthesis of fine chemicals. In this study, lipase from Thermomyces lanuginosus (Lecitase Ultra™) was used to catalyze the synthesis of flavor esters, i.e., methyl butanoate and methyl benzoate by esterification of the acids with methanol in a microfluidic system. Maximum reaction rates of 195 and 115 mM min corresponding to catalytic efficiencies (k /K ) of 0.30 and 0.24 min mM as well as yield conversion of 54 and 41 % were observed in methyl butanoate and methyl benzoate synthesis, respectively. Catalytic turnover (k ) was higher for methyl butanoate synthesis. Rate of synthesis and yield decreased with increasing flow rates. For both esters, increase in microfluidic flow rate resulted in increased advective transport over molecular diffusion and reaction rate, thus lower conversion. In microfluidic synthesis using T. lanuginosus lipase, the following reaction conditions were 40 °C, flow rate 0.1 mL min, and 123 U g enzyme loading found to be the optimum operating limits. The work demonstrated the application of enzyme(s) in a microreactor system for the synthesis of industrially important esters.
酶催化被认为是合成精细化学品最环保的工艺之一。在本研究中，来自嗜热栖热菌的脂肪酶（Lecitase Ultra™）被用于在微流控系统中通过酸与甲醇的酯化反应催化合成风味酯，即丁酸甲酯和苯甲酸甲酯。在丁酸甲酯和苯甲酸甲酯的合成中，分别观察到最大反应速率为195和115 mM min，对应催化效率（k /K ）为0.30和0.24 min mM，产率转化率分别为54%和41%。丁酸甲酯合成的催化周转率（k ）更高。合成速率和产率随流速增加而降低。对于这两种酯，微流控流速的增加导致平流传输超过分子扩散和反应速率，从而转化率降低。在使用嗜热栖热菌脂肪酶的微流控合成中，发现以下反应条件：40°C、流速0.1 mL min和酶负载量123 U g是最佳操作极限。这项工作展示了酶在微反应器系统中用于合成工业上重要的酯的应用。
