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• Thermophilic lipase was immobilized in inorganic nanoflower via biomimetic mineralization. • The immobilized enzyme showed favorable catalytic activity and stability. • The immobilized enzyme possessed excellent reusability and long-term storage stability. Thermophilic lipase QLM from Alcaligenes sp. was successfully immobilized in Cu 3 (PO 4) 2 -based inorganic hybrid nanoflower through biomimetic mineralization. The morphology, structure and element composition of immobilized enzyme were systemically characterized to elucidate the successful loading of enzyme molecules. The optimal temperature (65 °C) and pH (8.0) of immobilized enzyme were then determined by monitoring the hydrolysis of p -nitrophenyl caprylate. Moreover, compared with free enzyme, immobilized enzyme in inorganic hybrid nanoflower exhibited enhanced stability against thermal, pH and metal ions, attributing to the protective effect of nanoflower shell. Additionally, the immobilized enzyme possessed excellent reusability and long-term storage stability, with slightly decreased activity after being repeatedly used for 8 cycles or stored in water at room temperature for 4 weeks. Overall, the immobilization in inorganic hybrid nanoflower provided a facile and effective approach for the preparation of immobilized enzymes with favorable activity, stability and reusability, and thus the strategy showed great potential in developing ideal catalysts for future biocatalytic applications. [ABSTRACT FROM AUTHOR]

• Thermophilic lipase was immobilized in bio-based metal-organic frameworks. • The immobilized enzyme exhibited favorable catalytic activity and stability. • The immobilized enzyme could efficiently catalyze the biodiesel synthesis. Herein, thermophilic lipase QLM from Alcaligenes sp. has been successfully immobilized in bio-based metal-organic frameworks (MOFs) through biomimetic mineralization, using zinc acetate and adenine as metal ion and organic ligand, respectively. The morphology and structure of lipase@Bio-MOF was systematically characterized by scanning electron microcopy (SEM), transmission electron microcopy (TEM), powder X-ray diffraction (PXRD) and Fourier transform infrared spectra (FT-IR). The enzyme loading in immobilized enzyme was measured to be 15.9 % by thermogravimetric analysis (TGA). Further, it was demonstrated to possess favorable catalytic activity and stability under high temperature and alkaline conditions and in the presence of metal ions, using the hydrolysis of p -nitrophenyl caprylate as a model. Finally, the immobilized enzyme was successfully applied in the preparation of biodiesel through the trans-esterification of sunflower oil with methanol, obtaining a conversion of >60 % at a high oil/methanol ratio of 8:1. Meanwhile, it showed excellent recyclability during the biodiesel production, and no changes of morphology and crystal structure were observed after being used for 3 cycles. Overall, the immobilized lipase in bio-based MOFs provided an economically and environmentally viable biocatalyst for the synthesis of biodiesel. [ABSTRACT FROM AUTHOR]