超声对α-淀粉酶活性和结构特性的影响

Effect of Ultrasound on Activity and Structure ofα-Amylase

该研究借助米氏方程、圆二色谱和荧光光谱,考察超声对α-淀粉酶酶活力、酶促动力学和分子结构的影响,揭示超声对α-淀粉酶活性的影响机制。结果表明,α-淀粉酶酶活力在超声温度45℃、超声功率密度2.85 W/cm3、超声时间5 min时比未经超声处理的α-淀粉酶酶活力提高22.30%。酶促动力学分析结果显示,与对照相比,超声处理后α-淀粉酶的Vmax提高9.56%,Km降低23.58%。圆二色谱和荧光光谱分析可知,超声处理能改变α-淀粉酶的分子结构,使其结构更加整齐有序,且暴露更多的活性位点。超声波对提高α-淀粉酶的活性有积极作用。

Via Michaelies-Menten equation,circular dichroism,and fluorescence spectroscopy,this study aims to investigate the effect of ultrasound on activity,enzyme kinetics,and molecular structure ofα-amylase and reveal the underlying mechanism.The results showed that the activity ofα-amylase was 22.30%higher after the ultrasonication at 45℃and power density of 2.85 W/cm3 for 5 min.The results of enzyme kinetic analysis showed that the Vmax of ultrasound-treatedα-amylase was 9.56%higher and Km was 23.58%lower than those of the control.The analysis of circular dichroism and fluorescence spectroscopy revealed that ultrasound treatment could change the molecular structure ofα-amylase,making it more neat and orderly and enabling it to expose more active sites.In summary,ultrasound had positive influence on improving the activity ofα-amylase.