A new approach to synthesis of benzyl cinnamate: Optimization by response surface methodology

• Lipase-catalyzed synthesis of benzyl cinnamate was optimized in isooctane.
• A 5-level-4-factor central composite design is successfully established.
• The effects of several parameters and their mutual interaction were analyzed.
• Under the optimum condition, the yield reaches 97.7%.

In this work, the new approach to synthesis of benzyl cinnamate by enzymatic esterification of cinnamic acid with benzyl alcohol is optimized by response surface methodology. The effects of various reaction conditions, including temperature, enzyme loading, substrate molar ratio of benzyl alcohol to cinnamic acid, and reaction time, are investigated. A 5-level-4-factor central composite design is employed to search for the optimal yield of benzyl cinnamate. A quadratic polynomial regression model is used to analyze the experimental data at a 95% confidence level (P < 0.05). The coefficient of determination of this model is found to be 0.9851. Three sets of optimum reaction conditions are established, and the verified experimental trials are performed for validating the optimum points. Under the optimum conditions (40 °C, 31 mg/mL enzyme loading, 2.6:1 molar ratio, 27 h), the yield reaches 97.7%, which provides an efficient processes for industrial production of benzyl cinnamate.