Mushroom tyrosinase immobilized in metal–organic frameworks as an excellent catalyst for both catecholic product synthesis and phenolic wastewater treatment

Abstract

BACKGROUND Metal–organic frameworks (MOFs) have gained increasing attention with ever‐expanding applications. Developing new MOF‐based immobilized enzymes with new applications is required, not only for demonstrating the generality and applicability of using MOFs for enzyme immobilization, but also to provide potential biocatalysts for industrial applications. To the best of the authors’ knowledge, this is the first report of immobilizing mushroom tyrosinase on zeolitic imidazolate frameworks (ZIFs), with two new applications being developed. RESULTS Upon immobilization through a one‐pot in situ encapsulation approach, the resultant tyrosinase@ZIF‐8 was characterized in structural features and catalytic properties. It was much more stable against pH and temperature relative to the free enzyme. The new biocatalyst was highly efficient in catalyzing the synthesis of catecholic products with pharmacological benefits (l‐DOPA, piceatannol and 3′‐hydroxypterostilbene) and in eliminating phenolic pollutants (phenol, p‐cresol, p‐chlorophenol). Excellent productivities were obtained for the synthesis of the three catecholic products (0.14, 1.38 and 1.46 g L−1 h−1, respectively). A complete removal of the three phenolic pollutants was achieved within 2.5 h, superior to other processes mediated by the same enzyme, or others, immobilized on different supports. The reusability of the new biocatalyst can be remarkably improved by entrapment into polyvinyl alcohol‐alginate gel. CONCLUSIONS Tyrosinase can be immobilized on a new type of MOF with advantages such as easy preparation and excellent catalytic performance. This novel immobilization strategy for tyrosinase offers an excellent biocatalyst potent for both catecholic product synthesis and phenolic wastewater treatment. © 2021 Society of Chemical Industry (SCI).

Tyrosinase Magnetic Cross-Linked Enzyme Aggregates: Biocatalytic Study in Deep Eutectic Solvent Aqueous Solutions

“…In the FTIR spectra of tyrosinase CLEAs and mCLEAs, the enzymes’ characteristic absorption bands known as Amide I (peaks at 1654 and 1652 cm −1 ), Amide II (1540 cm −1 ) and Amide III (peaks in the range of 1250–1350 cm −1 ) are observed for both biocatalytic systems. These bands are mostly associated with the C=O stretching vibration (Amide I), the N-H bending vibration and the C-N stretching vibration (Amide II and Amide III) [ 26 ]. FTIR analysis has also been used by other researchers with the aim of proving the successful preparation of cellulase CLEAs and cellulase magnetic CLEAs, by observing similar bands [ 51 ].…”

“…Tyrosinase has been immobilized on various carriers and its biocatalytic properties have been studied and compared to those of the free enzyme [ 25 , 26 , 27 , 28 , 29 ]; these studies showed that the immobilized form exhibits enhanced activity and stability. Cross-linking of enzyme molecules is another immobilization technique used for tyrosinase.…”

Metal–Organic Framework for the Immobilization of Oxidoreductase Enzymes: Scopes and Perspectives

“…Especially for Lac, this technology showed great application potential in the field of pollutant degradation. Wei et al reported for the first time the complete removal of eliminated phenol, p-cresol, and p-chlorophenol by immobilizing tyrosinase on Zeolite imidazole framework-8 (ZIF), which showed high efficiency in the degradation of phenolic pollutants [29]. Jiang et al prepared Lac at Cu (PABA) using an efficient one-pot approach.…”

Enzyme-Immobilized Porous Crystals for Environmental Applications

“…This feature effectively shields enzymes from external environmental influences to some extent, thereby enhancing their stability. MOF−enzyme composites, particularly those involving ZIF-8, have found widespread application in the degradation of industrial dyes, 53 phenolic compounds, 54 and pesticides. 55 Regrettably, the ZIF-8 shell presents a limitation with its narrow aperture (3.4 Å), significantly impeding the diffusion of organic pollutants and consequently slowing down pollutant degradation.…”