腈水合酶催化水合制备丙烯酰胺反应的研究

对腈水合酶催化水合生产丙烯酰胺反应的条件进行了优化,在最佳反应温度和pH下,采用正交实验法考察了丙烯腈含量、菌体浓度、反应时间3因素对腈水合酶催化反应转化率的影响。结果表明,在腈水合酶催化反应中,丙烯腈含量是最主要的影响因素。最佳的反应条件为:303 K,pH 7.5,菌体稀释10倍,丙烯腈体积分数7％,反应时间120 s。在此条件下达到了最高酶活性6 770 μmol／(min·mL),比未优化之前的酶活性增加了30％以上。最后,对腈水合酶进行了催化反应动力学研究,并通过酶稳定性实验表明了酶的高稳定性。

Study of Acrylonitrile Hydration Catalyzed by Nitrile Hydratase to Arylamide

The reaction conditions of acrylonitrile hydration to acrylamide catalyzed by nitrile hydratase wereinvestigated. At moderate reaction temperature and pH, three relevant factor concerning the reaction--concentration of acrylonitrile, concentration of enzyme and reaction temperature--were studied. Concentrationof acrylonitrile was the key factor in hydration. Under optimal conditions, the reaction gave maximum enzyme activity of 6 770 μmol/(min·mL), which was about 30% or so higher than under unoptimized conditions. The optimal conditions were: reaction temperature 303 K;pH 7.5; acrylonitrile concentration 7% ; enzyme dilution 10 times,and reaction time 120 s.The enzyme was highly stable and its catalytic reaction kinetics was also studied.