Study on Synthesis of 1-Phenylethyl Acetate by Enzymatic Kinetic Resolution

In this study, porcine pancreatic lipase (PPL), Candida antarctica lipase (CAL-B, free state) and Novozyme 435 lipase were used as catalysts to establish an efficient, highly selective and environmentally friendly biocatalysis system for the synthesis of 1-phenylethyl acetate (PEA). Lipase species, acyl donor, reaction solvent, amount of lipase, lipase repeatability, reaction time, substrate concentration and reaction temperature were used as variables to study the characteristics of lipase catalytic kinetics for the resolution of 1-phenylethanol (PE). The results showed that Novozym 435 lipase was the best enzyme in the n-hexane solvent system. The optimal reaction temperature was 60°C, the optimal lipase addition amount was 40 mg/ml, the concentration of PE was 100 mmol/ml, and the concentration of vinyl acetate was 500 mmol/L. After 24 hours of reaction, The yield of PEA was 61.49%. When Novozym 435 lipase was recovered and applied for 4 times or more, the reaction time was reduced to 1 h, the reaction temperature was reduced to 30°C, the addition of lipase was reduced to 20 mg/ml, and the yield of PEA remained stable above 40%. The K_m/V_max was 0.8943 h, V_max was 0.118, and K_m was 0.105 mol/L. Obtain the Michaelis-Menten model: V₀=(0.118·[S])/(0.105 [S]). This study not only enriched the basic theoretical knowledge of non-aqueous enzymology, but also provided a reference for the application of lipase in the industrial production of spices.