乙醇对环糊精葡萄糖基转移酶催化作用影响的研究
首发时间:2009-09-29
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为4.71L/mol,ΔG=-3.84KJ/mol-1;环己烷与β-环糊精Ks为19.56L/mol,ΔG=-7.37 KJ/mol-1。环己烷与β-环糊精的结合能力大大高于乙醇,故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来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,并能在一定程度上减少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。
关键词: 乙醇 环糊精葡萄糖基转移酶 环化作用 偶合作用
For information in English, please click here
Studies on the effect of ethanol on the catalysis of CGTase
Abstract:UV absorption spectroscopy was used to study the stability constant (Ks) and free energy change (ΔG)of the inclusion reaction of ethanol or cyclohexane withβ-cyclodextrin. The Ks and ΔG of ethanol withβ-cyclodextrin was 4.71L/mo and-3.84KJ∙mol-1;the Ks and ΔG of cyclohexane withβ-cyclodextrin was 19.56L/mo and-7.37KJ∙mol-1. 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 than 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.
Keywords: ethanol cyclodextrin glycosyltransferase cyclization coupling
基金:
论文图表:
引用
No.3559849474612542****
同行评议
共计0人参与
勘误表
乙醇对环糊精葡萄糖基转移酶催化作用影响的研究
评论
全部评论0/1000