乙醇对环糊精葡萄糖基转移酶催化作用的影响  

Effect of Ethanol on the Catalysis of CGTase

作　　者：王亮[1,2] 顾正彪[1,2] 程力[2] 洪雁[2] 

机构地区：[1]江南大学食品科学与技术国家重点实验室,无锡214122 [2]江南大学食品科学与技术学院,无锡214122

出　　处：《高等学校化学学报》2010年第6期1190-1194,共5页Chemical Journal of Chinese Universities

基　　金：国家“八六三”计划项目(批准号:2006AA10Z335);教育部创新团队计划(批准号:IRT0627);高等学校学科创新引智计划(批准号:B07029);江南大学自主科研计划资助

摘　　要：采用紫外吸收光谱法测定了乙醇、环已烷与β-环糊精包合反应稳定常数及自由能变化,确定乙醇与β-环糊精的包合反应稳定常数Ks=4.71 L/mol,ΔG=-3.84 kJ/mol;环己烷与β-环糊精包合反应的Ks=19.56 L/mol,ΔG=-7.37 kJ/mol.环己烷与β-环糊精的结合能力大大高于乙醇,故用乙醇提高其产率的机理不同于传统工艺中所添加的环己烷.通过测定乙醇对环糊精葡萄糖基转移酶催化作用的影响进一步探究其作用机理.结果表明,乙醇不仅能提高环糊精葡萄糖基转移酶环化作用的活力,并在一定程度上阻止对转化环糊精有抑制作用的小分子糖的形成,还可以减轻环糊精葡萄糖基转移酶对环糊精的水解及偶合作用,从而提高环糊精的产率.UV absorption spectroscopy was used to study the stability constant（Ks） and free energy change（ΔG）of the inclusion reaction of ethanol or cyclohexane with β-cyclodextrin.The Ks and ΔG of ethanol with β-cyclodextrin was 4.71 L/mol and-3.84 kJ/mol;the Ks and ΔG of cyclohexane with β-cyclodextrin was 19.56 L/mol and-7.37 kJ/mol.The binding ability of cyclohexane with β-cyclodextrin is higher than that of ethanol.The effect of ethanol added is shown not to be related to the product inhibition of CGTase,the way of action is different from cyclohexane.Ethanol can not only increase the activities of CGTase,but also inhibit the effect of the coupling reaction and hydrolysis reaction,resulting in an increase in cyclodextrins yield.

关 键 词：乙醇 环糊精葡萄糖基转移酶 环化作用 偶合作用 

分 类 号：O629.12[理学—有机化学] O641.3[理学—化学]