【摘要】 研究了有机溶剂中猪胰脂肪酶催化正己酸和无水乙醇合成己酸乙酯的反应。以正己酸和无水乙醇在各种反应介质中进行酶催化反应,用气相色谱检测生成的己酸乙酯,考察反应介质、底物浓度、底物摩尔比、加酶量、反应时间对产率的影响。发现在高底物浓度和低底物浓度的条件下,有机溶剂介质对反应的影响是不同的。采用中等底物浓度,选择lgP值适中的溶剂为介质最合适。适当的反应条件为:以环己烷为反应介质,正己酸浓度0.6mol/L,n(正己酸)∶n(无水乙醇)=1∶1.25,加酶量15g/L,反应温度37℃,反应24h后,产率达到90.5%。该文的底物浓度较高,是文献[1,10,11,17]报道的1.5～3.0倍,获得了相近的产率。更多还原

【Abstract】 The synthesis of ethyl caproate from caproic acid and anhydrous ethanol catalyzed by pocine pancreas lipase in organic solvent was investigated.The biotransformation was carried out in several kinds of reaction media.The produced ethyl caproate was determined by gas chromatography.The effects of reaction media,substrate concentration,mole ratio of substrates,enzyme amount and reaction time on the conversion yield were investigated.It was found that the influences of organic solvent on the enzymatic reaction with low concentration of substrate were different from those with the high concentration of substrate.Middle concentration of substrate and moderate lgP value of solvent were suitable.The appropriate conditions for biocatalysis were:0.6 mol/L caproic acid in cyclohexane,mole ratio of caproic acid and anhydrous ethanol 1∶1.25,with 15 g/L lipase,at 37 ℃.After 24 h reaction,the yield was 90.5%.When the substrate concentration was 1.5～3.0 times as high as reported by the references[1,10,11,17],the similar yield was obtained.更多还原