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BACKGROUND: High selectivity, fewer reaction steps, and energy conservation are the most important advantages of the enzymatic synthesis of sucrose-6-acetate. To improve the enzymatic synthesis efficiency, a solvent system involving N,N-dimethylformamide (DMF) for lipase-catalyzed synthesis of sucrose-6-acetate was studied.RESULTS: Using Lipozyme TL IM as the catalyst, tert-amyl alcohol was screened out as the auxiliary solvent and complexed with DMF at 1/1 (v/v) ratio. The optimized technology conditions for the enzymatic synthesis of sucrose-6-acetate in the above solvent system were as follows: 100 ml composite solvent with sucrose (2.0%, w/v), vinyl acetate (2.90 M), and Lipozyme TL IM (20 mg/ml) was oscillated at 160 rpm in a water bath at 45 °C for 16 h. The esterification rate and the 6-position esterification rate of sucrose were 88.9 ± 1.3% and 94.2 ± 1.2%, respectively. Raising the sucrose concentration to 7.0% and reacting by mechanical stirring at 45 °C in 1000 ml composite solvent could also achieve ideal esterification effects (esterification rate: 87.2 ± 1.0%, 6-position esterification rate: 90.7 ± 1.6%). CONCLUSIONS: As a reaction medium for the enzymatic synthesis of sucrose-6-acetate, the DMF/tert-amyl alcohol solvent was significantly more efficient than the DMSO composite solvent reported in the literature; therefore, the studied solvent could be an ideal application prospect.

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