Efficient and sustainable preparation of cinnamic acid flavor esters by immobilized lipase microarray

Abstract

Green and effective synthesis of flavor esters is a long-term interest in food, cosmetic and pharmaceutical industries. Here, an immobilized lipase microarray was prepared by immobilizing lipase CSL on hydrophobically modified ordered mesoporous silicon (CSL@OMS-C8) for the enzymatic production of cinnamic esters with different flavors. The results showed that the CSL@OMS-C8, with an immobilization capacity of 249.3 ± 11.1 mg/g, exhibited 1.6 times higher catalytic activity than that of free lipase at the optimum temperature of 70 °C. The maximum yield of benzyl cinnamate reached 97.3% in 2 h with the corresponding CE value of 650.5 μmol/g · h, leading to the highest record compared to the current literature. Besides, the CSL@OMS-C8 could maintain 81.4 ± 1.1% conversion for cinnamic acid after five-cycle reuse, thus revealing the high stability and reusability of immobilized lipase. Finally, the broad applicability of the immobilized lipase microarray was confirmed by its capacity to successfully catalyze the synthesis of methyl cinnamate, ethyl cinnamate, butyl cinnamate, geranyl cinnamate and isoamyl cinnamate. This study reveals new insights on the efficient and sustainable enzymatic approach to produce natural cinnamic acid flavor esters and, consequently, could pave the way for the natural and clean production in food industries.