麦芽中脂肪酶活性检测及酶学性质的研究  

Detection of lipase activity in malt and its enzymatic properties research

作　　者：康开萍[1] 张盛贵[1] 李红[2] 肖侠[1] 陈光斌[1] 邵威平[1] 

机构地区：[1]甘肃农业大学食品科学与工程学院,甘肃兰州730070 [2]中国食品发酵工业研究院,北京100027

出　　处：《食品工业科技》2013年第6期190-193,共4页Science and Technology of Food Industry

基　　金：广州市珠江科技新星项目(2012J2200050)

摘　　要：以乙酸对硝基苯酚酯(p-NPA)为底物,采用对硝基苯酚法测定了麦芽中脂肪酶的活性,并对其酶学性质进行了研究。实验结果表明,麦芽中脂肪酶的最适反应pH为8.5,与5mmol/L的p-NPA的最适反应体积比为1∶7,金属离子Mg2+对麦芽脂肪酶活性有显著的抑制作用,Fe3+、K+则有一定激活作用;该酶热稳定性较强,40℃水浴保温120min,其酶活性几乎保持不变,70℃保温120min后接近失活。麦芽脂肪酶对p-NPA的酶动力学常数Km为0.13mmol/L,Vm值为0.016mg/min。Taken the 4-nitrophenyl acetate （p-NPA） as the substrate, we detected the activity of lipase in malt and studied its enzymatic properties. Results showed that the optimum pH of iipase activity was 8.5,the optimum reaction volume ratio with 5mmol/L p-NPA was 1：7, In 10mmol/L the presence of different metal ions Mg2＋ could significantly inhibit malt lipase activity and Fe3＋,K＋ could promote its activity in some degree. The lipase in malt had strong thermostability, it could almost maintain the same activity in 40℃ water bath after 120 minutes and finally became inactivation after 120min in 70℃ water bath preservation. Kinetic constants （Kin and Vm） of malt lipase to p-NPA were 0.13mmol/L and 0.016mg/min.

关 键 词：麦芽 脂肪酶 酶学性质 动力学常数 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]