State Key Laboratory for Macromolecule Drugs and Large-Scale Manufacturing, School of Pharmaceutical Sciences, Liaocheng University, Liaocheng, Shandong 252059, People's Republic of China.
Langmuir. 2024 Sep 3;40(35):18727-18735. doi: 10.1021/acs.langmuir.4c02436. Epub 2024 Aug 19.
β-Glucosidase (β-G) holds promising applications in various fields, such as biomass energy, food, pharmaceuticals, and environmental protection, yet its industrial application is still limited by issues of stability and recycling. Herein, we first immobilized β-G onto the surface of magnetic chitosan nanoparticles (MCS/β-G) through adsorption methods. Subsequently, utilizing the metal-organic framework (MOF), CaBDC, which possesses good stability under acidic conditions, we encapsulated MCS/β-G. The resulting biocatalyst (MCS/β-G@CaBDC) exhibited excellent activity and recyclability. MCS/β-G@CaBDC can convert 91.5% of cellobiose to glucose in 60 min and maintained 81.9% activity after 10 cycles. The apparent value of MCS/β-G@CaBDC was 0.148 mM, lower than free β-G (0.166 mM) and MCS/β-G (0.173 mM). The CaBDC layer increased the mass transfer resistance of the reaction but also triggered structural rearrangement of β-G during the encapsulation process. This resulted in the β-sheet content rising to 68.4%, which, in turn, contributed to enhancing the rigidity of β-G. Moreover, the saturated magnetic strength of this biocatalyst could reach 37.3 emu/g, facilitating its magnetic recovery. The biocatalyst prepared in this study exhibits promising application prospects, and the immobilization method can provide valuable insights into the field of enzyme immobilization.
β-葡萄糖苷酶（β-G）在生物质能、食品、制药和环境保护等领域具有广阔的应用前景，但由于其稳定性和可回收性问题，其工业应用仍受到限制。本研究首次通过吸附法将β-G固定到磁性壳聚糖纳米粒子（MCS/β-G）表面。随后，利用具有良好酸性条件下稳定性的金属有机骨架（MOF）CaBDC 对 MCS/β-G 进行封装。所得生物催化剂（MCS/β-G@CaBDC）表现出优异的活性和可回收性。MCS/β-G@CaBDC 在 60 min 内可将 91.5%的纤维二糖转化为葡萄糖，经过 10 次循环后仍保持 81.9%的活性。MCS/β-G@CaBDC 的表观 值为 0.148 mM，低于游离β-G（0.166 mM）和 MCS/β-G（0.173 mM）。CaBDC 层增加了反应的传质阻力，但也在封装过程中引发了β-G 的结构重排。这导致β-折叠含量上升至 68.4%，从而增强了β-G 的刚性。此外，该生物催化剂的饱和磁化强度可达 37.3 emu/g，有利于其磁性回收。本研究制备的生物催化剂具有广阔的应用前景，固定化方法可为酶固定化领域提供有价值的见解。
