Lipase@zeolitic imidazolate framework ZIF-90: A highly stable and recyclable biocatalyst for the synthesis of fruity banana flavour

A zeolitic imidazolate framework (ZIF-90) has been synthesized through solvothermal method. The structure was characterized by means of FT-IR spectroscopy, X-ray diffraction, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDS). The synthesized ZIF-90 was applied as a support for immobilization of porcine pancreatic lipase (PPL). The immobilized enzyme (PPL@ZIF-90) exhibited immobilization yield and efficiency of 66 +/- 1.8% and 89 +/- 1.4%, respectively. The pH and thermal stability of PPL was improved after immobilization and the initial activity was retained at about 57% after 20days of storage at 4 degrees C for PPL@ZIF-90. Moreover, about 57% of the original activity was remained following 10 cycles of application. In Michaelis-Menten kinetic studies, K-m value for PPL@ZIF-90 was lower, while, the V-max was higher than free PPL Moreover, optimized conditions to produce fruity banana flavour upon esterification of butyric acid were investigated. The optimum esterification yield was 73.79 +/- 1.31% in the presence of 245 mg PPL@ZIF-90, alcohol/acid ratio of 2.78 and 39 h reaction time. PPL@ZIF-90 showed 39% relative esterification yield after six cycles of reuse. The results suggested that PPL@ZIF-90 can be used as a potential effective biocatalyst for synthesis of isoamyl butyrate. (C) 2020 Published by Elsevier B.V.