Key Laboratory of Green Manufacturing and Biosynthesis of Food Bioactive Substances, China General Chamber of Commerce, School of Food and Health, Beijing Technology and Business University, Beijing 100048, China.
School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China.
Int J Biol Macromol. 2024 Jun;270(Pt 1):132312. doi: 10.1016/j.ijbiomac.2024.132312. Epub 2024 May 12.
This study aimed to immobilize β-galactosidase (β-GAL) into enhanced polystyrene (PS) electrospun nanofiber membranes (ENMs) with functionalized graphene oxide (GO). Initially, GO sheets were functionalized by salinization with 3-aminopropyl triethoxysilane (APTES). Then the ENMs (PS, PS/GO, and PS/GO-APTES) were prepared and characterized. Then, the β-GAL was immobilized in the different ENMs to produce the β-GAL-bound nanocomposites (PS-GAL, PS/GO-GAL, and PS/GO-APTES-GAL). Immobilization of β-GAL into PS/GO-APTES significantly improved enzyme adsorption by up to 87 %. Also, PS/GO-APTES-GAL improved the enzyme activity, where the highest enzyme activity was obtained at enzyme concentrations of 4 mg/L, 50 °C, and pH 4.5. Likewise, the storage stability and reusability of immobilized β-GAL were improved. Furthermore, this process led to enhanced catalytic behavior and transgalactosylation efficiency, where GOS synthesis (72 %) and lactose conversion (81 %) increased significantly compared to the free enzyme. Overall, the immobilized β-GAL produced in this study showed potential as an effective biocatalyst in the food industry.
本研究旨在将β-半乳糖苷酶（β-GAL）固定在功能化氧化石墨烯（GO）增强的聚苯乙烯（PS）静电纺纳米纤维膜（ENMs）中。首先，通过 3-氨丙基三乙氧基硅烷（APTES）盐化对 GO 片进行功能化。然后制备并表征了 ENMs（PS、PS/GO 和 PS/GO-APTES）。然后，将β-GAL 固定在不同的 ENMs 中以制备β-GAL 结合纳米复合材料（PS-GAL、PS/GO-GAL 和 PS/GO-APTES-GAL）。β-GAL 固定到 PS/GO-APTES 中可显著提高酶吸附率，最高可达 87%。此外，PS/GO-APTES-GAL 提高了酶活性，在酶浓度为 4mg/L、50°C 和 pH4.5 时获得了最高的酶活性。同样，固定化β-GAL 的储存稳定性和可重复使用性也得到了提高。此外，该过程导致催化行为和转半乳糖基化效率得到增强，与游离酶相比，GOS 合成（72%）和乳糖转化率（81%）显著提高。总的来说，本研究中制备的固定化β-GAL 有望成为食品工业中有效的生物催化剂。
