Construction of a Tannase-Immobilized Magnetic Graphene Oxide/Polymer Nanobiocatalyst with Enhanced Enzyme Stability for High-Efficiency Transformation of Tannins

Abstract

Highly efficient biotransformation of natural compounds into sustainable biochemical products has attracted great attention. The integration of nanoscience and biotechnology provides attractive solutions for this purpose. Herein, we report the fabrication of a nanobiocatalyst employing a magnetic graphene oxide/polymer nanocomposite as a robust carrier for immobilizing the tannase enzyme, which catalyzes the bioconversion of tannin into gallic acid and glucose. Attributed to the covalent immobilization and propitious interface properties of the coated polymers comprising polyethylenimine and sodium hyaluronate, the nanobiocatalyst is stable without compromising the enzymatic activity. The nanobiocatalyst exhibits 91.8% activity of original tannase and a high enzyme bound amount of 356.8 mg g −1 . The stability tests at variable temperatures (30−80 °C) and under pH conditions (4.0−9.0), various inhibitors, and a long-term storage process (25 days) reveal that the heterofunctional support and surface microenvironment facilitate better stability, adaptability, and tolerance ability of the nanobiocatalyst modified with a multicomponent polymer in comparison to the free enzyme and the nanobiocatalyst modified with the monocomponent polyethylenimine. The nanobiocatalyst maintains 94.2% of its initial activity after 10 consecutive uses and is 100% recoverable by applying an external magnet. Moreover, the nanobiocatalyst is used to hydrolyze 96.5 and 95.1% tannins in extracts from Chinese Torreya grandis testa and cake, respectively. These results establish the practicability of magnetic graphene oxide-based supports for immobilizing tannase and the promising application of immobilized tannase for efficient tannin hydrolysis.

Fabrication of a Magnetic Porous Organic Polymer for α-Glucosidase Immobilization and Its Application in Inhibitor Screening

“…Capillary electrophoresis (CE), with its high separation efficiency, short analysis time, and smaller sampling consumption, is regarded as a powerful microanalytical technique and has been widely applied to screen enzyme inhibitors in combination with an enzymatic reaction, in which free enzyme or immobilized enzyme was employed to catalyze a specific reaction . Compared with free enzyme, the immobilized one exhibits improved stability and enhanced tolerance to pH and temperature and could be separated from the reaction medium for repeated use. , For enzyme immobilization, the key issue is pursuing suitable carrier materials and effective immobilization methods since they greatly influence the catalytic activity and operational performance of the immobilized enzyme.…”

“…11 Compared with free enzyme, the immobilized one exhibits improved stability and enhanced tolerance to pH and temperature and could be separated from the reaction medium for repeated use. 12,13 For enzyme immobilization, the key issue is pursuing suitable carrier materials and effective immobilization methods since they greatly influence the catalytic activity and operational performance of the immobilized enzyme.…”

In Silico and In Vitro Evaluation of Antiobesogenic and Osteoprotective Effect of Pomegranate Juice Fermented by Tannin Acyl Hydrolase and Lactobacillus vespulae DCY75 via the Wnt/β-Catenin Pathway

“…13 Currently, the bioconversion of tannin has emerged as a prominent area of scientific investigation owing to its commercial importance, enhanced transformation into an amorphous state facilitating rapid absorption, and significant relevance to various end products. 14 Notably, the global market has witnessed an evident trend of increased consumption and demand for processed pomegranate products, with pomegranate juice being at the forefront of this trend. Consequently, this phenomenon is expected to garner substantial attention and contribute to significant revenue growth in the global market.…”

“…However, the limited absorption and partial hydrolysis of ETs and GTs lead to the release of ellagic acid (EA) and gallic acid (GA) in the bloodstream, respectively . Currently, the bioconversion of tannin has emerged as a prominent area of scientific investigation owing to its commercial importance, enhanced transformation into an amorphous state facilitating rapid absorption, and significant relevance to various end products . Notably, the global market has witnessed an evident trend of increased consumption and demand for processed pomegranate products, with pomegranate juice being at the forefront of this trend.…”