使用酶法合成了一系列不同烷基链长的β-D-烷基葡萄糖苷.结果表明,除甲基糖苷外,烷基碳链越长,反应初速度越低,糖苷的最终收率越低.从热力学角度系统地研究了这些糖苷合成的平衡常数和吉布斯自由能变化.通过改变反应的平衡,提高了长链烷基糖苷的最终收率.当水含量从10％降至5％ (v/v),使用叔丁醇作为共溶剂,添加0.1 mol/L葡萄糖作为底物时,癸基糖苷的平衡得率从1.9％提高至6.1％.除了其他长链的烷基糖苷外,庚基糖苷也显示了明显的表面活性剂活性.%An array of ten β-D-glucopyranosides with varied alkyl chain lengths were enzymatically synthesized.It was found that for longeralkyl chains a lower initial rate and final yield of glucoside was obtained except for methyl glucoside because of the severe toxicity of methanol to the enzyme.From a thermodynamics point of view,the equilibrium constant and Gibbs free energy variation of the glucoside syntheses were systematically investigated.To improve the final yields of the glucosides containing long alkyl chains the equilibrium of the enzymatic glucoside synthesis was altered.The equilibrium yield of decyl β-D-glucoside increased from 1.9% to 6.1% when the water content was reduced from 10% to 5% (v/v) using tert-butanol as a cosolvent and 0.10 mol/L of glucose as a substrate.As for the other longer alkyl chain glucosides,heptyl β-D-glucoside was found to have significant surface activity as well.
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