Ultrasound-assisted enzymatic synthesis of cinnamyl acetate by immobilized lipase on ordered mesoporous silicon with CFD simulation and molecular docking analysis.

Flavor esters are used in food and cosmetic industries, but sustainable production remains a big challenging. This study proposed the ultrasound-assisted biosynthesis of cinnamyl acetate using self-made immobilized lipase CSL@OMS-C8, with computational fluid dynamics (CFD) and molecular simulations revealing the hydrodynamic properties and lipase-catalytic mechanisms. The results demonstrate that ultrasonication-intensified enzymatic reaction facilitated 96.6 % conversion of cinnamic alcohol, due to the ultrasound-assisted catalytic efficiency of 13.7 mmol/g·min. Molecular docking analysis identifies the lowest binding energy of -3.7 kcal·mol-1 between lipase and vinyl acetate, contributing to the highest conversion rates compared to acetic acid, ethyl acetate. CFD simulation indicates that ultrasonic energy waves promote substrate diffusion and mixing with lower shear stress. The catalytic stability of CSL@OMS-C8 was confirmed by 60.1 % of relative activity after 10-time reuse. This paper theoretically and experimentally studied the ultrasonic-assisted enzymatic synthesis of cinnamyl acetate, showcasing huge potential for sustainable production of flavor esters.