Urmia University, Faculty of Agriculture, Department of Food Science and Technology, Urmia, Iran.
Urmia University, Faculty of Agriculture, Department of Food Science and Technology, Urmia, Iran.
Carbohydr Polym. 2018 Nov 15;200:137-143. doi: 10.1016/j.carbpol.2018.07.096. Epub 2018 Aug 1.
β-galactosidase was successfully immobilized onto chitosan (CS)/polyvinyl alcohol (PVA) blend nanofibers through electrospinning. The effects of both polymer solution parameters and the electrospinning process conditions on the morphology of nanofibers and enzyme activity were studied. FESEM results showed that both morphology and diameter of the nanofibers were significantly influenced by the studied factors. The nanofiber mats obtained from CS/PVA at 50:50 mass ratio and conditions of 20 kV and 0.5 ml/h were selected as the optimized nanofibers, with the smallest diameter and most homogenous structure. On the other hand, catalytic activity of the β-galactosidase -immobilized nanofibers (Enzyme-NF) was not significantly changed with these factors. The catalytic activity of Enzyme-NF was 57.03% of free enzyme activity at pH 6.8 and 4 °C. Furthermore, it showed more temperature stability compared to free β-galactosidase at 50 °C. During 28 days of storage, Enzyme-NF samples retained 77% and 42% of its initial activity in 4 °C and 25 °C, respectively.
β-半乳糖苷酶通过静电纺丝成功固定在壳聚糖（CS）/聚乙烯醇（PVA）共混纳米纤维上。研究了聚合物溶液参数和静电纺丝工艺条件对纳米纤维形态和酶活性的影响。FESEM 结果表明，所研究的因素显著影响了纳米纤维的形态和直径。从 CS/PVA 质量比为 50:50、20 kV 和 0.5 ml/h 的条件下获得的纳米纤维垫被选为最佳纳米纤维，具有最小的直径和最均匀的结构。另一方面，β-半乳糖苷酶固定化纳米纤维（酶-NF）的催化活性并没有随着这些因素而显著变化。酶-NF 的催化活性在 pH 值为 6.8 和 4°C 时为游离酶活性的 57.03%。此外，与游离β-半乳糖苷酶相比，它在 50°C 时具有更高的温度稳定性。在 28 天的储存期间，酶-NF 样品在 4°C 和 25°C 下分别保留了初始活性的 77%和 42%。
