Catalytic synthesis of sucrose‐6‐acetate by lipase in <scp>DMF</scp> composite solvent

Abstract

Abstract 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. © 2022 Society of Chemical Industry (SCI).