Selective Catalytic Synthesis Of Sucrose-6-Ethyl Ester By Enzyme

Sucralose is derived from sucrose by replacing the hydroxyls in the 4,1’,6’position with chlorine, and revesing the stereo configuration at the 4 position. It is one of the most highly excellent performance of sweeteners. Sucrose-6-ethyl ester is an important intermediate in the preparation of sucralose. This article focuses on the enzymatic synthesis of sucrose-6-ethyl ester by transesterification of sucrose and vinyl acetate.Immobilized Lipozyme TL IM can catalyze the synthesis of sucrose-6-ethyl ester efficiently and high selectively. The optimal reaction conditions are as follows:tert-butanol/ DMSO= 4/1 (volume ratio) of mixed reaction system,0.02% of solvent water content, pH= 5-6; the enzyme concentration 80mg/mL; sucrose 0.06mol/L; vinyl acetate 0.12mol/L; the reaction temperature 35 ℃; magnetic speed 400r/min; the reaction time 10h; the yield of sucrose-6-ethyl ester can reach up to 74%.The influence of ultrasound fields on this enzyme-catalyzed reaction was studied. The results showed that:appropriate intensity and action time of ultrasound can effectively shorten the reaction time, strengthen the catalytic specificity of the enzyme.This thesis selected its further chlorinated product, sucralose-6-ethyl ester, to analyze by IR and MS.