State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, China; Group of Microbiological Engineering and Industrial Biotechnology, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, North Ren Min Road 2999, Shanghai 201620, China.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, China.
Carbohydr Polym. 2018 Sep 15;196:457-464. doi: 10.1016/j.carbpol.2018.05.055. Epub 2018 May 18.
Properties of bacterial nanocellulose (BNC) produced by four different strains were studied and compared for laccase immobilization. Scanning electron microscope inspection indicated the four types of BNC had obvious differences in fiber density, diameter and distribution. BNC hydrogel demonstrated the highest fracture stress of 2.44 Mpa and the highest Young's modulus of 12.76 Mpa. Brunauer-Emmett-Teller analysis suggested the four BNC had significant difference in specific surface area, total pore volume and average pore size. Laccase was immobilized on BNC carriers via adsorption. Kinetic studies showed that the four types of BNC-immobilized laccase had different affinity with substrate, and all types of immobilized laccase showed high operational stability after ten consecutive biocatalytic cycles of reaction. The results suggest that the structure diversity of BNC from various strains may directly result in different efficiency in laccase immobilization, and a looser fiber network in BNC with larger porosity is helpful for enzyme immobilization.
研究了四种不同菌株生产的细菌纳米纤维素（BNC）的性质，并对其进行了比较，以用于漆酶固定化。扫描电子显微镜检查表明，四种类型的 BNC 在纤维密度、直径和分布上有明显的差异。BNC 水凝胶表现出最高的断裂应力 2.44 Mpa 和最高的杨氏模量 12.76 Mpa。BET 分析表明，四种 BNC 在比表面积、总孔体积和平均孔径上有显著差异。漆酶通过吸附固定在 BNC 载体上。动力学研究表明，四种类型的 BNC 固定化漆酶与底物的亲和力不同，所有类型的固定化漆酶在连续进行十次生物催化反应循环后都表现出很高的操作稳定性。结果表明，不同菌株的 BNC 结构多样性可能直接导致漆酶固定化效率的不同，而具有较大孔隙率的更疏松的 BNC 纤维网络有利于酶的固定化。
