Improved Thermal and Reusability Properties of Xylanase by Genipin Cross-Linking to Magnetic Chitosan Particles
Improved Thermal and Reusability Properties of Xylanase by Genipin Cross-Linking to Magnetic Chitosan Particles
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DOI：
10.1007/s12010-018-2928-7
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发表时间：
2019-06-01
影响因子：
3
通讯作者：
Amaro-Reyes, Aldo
中科院分区：
文献类型：
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作者：
Gracida, Jorge;Arredondo-Ochoa, Teresita;Amaro-Reyes, Aldo
酶逐渐比化学方法更受欢迎，但由于其低稳定性和低产物回收率，商业酶应用仍然有限，因此需要应用固定化技术以重复使用。本工作的目的是制备稳定的磁性壳聚糖交联木聚糖酶复合物，描述这些复合物的一些特性，并评价固定化酶的热稳定性和重复使用性。以壳聚糖为模板，通过原位共沉淀法制备了磁性颗粒与木聚糖酶交联。温度，pH值，动力学参数，和可重复使用的游离和固定化木聚糖酶的效果进行了评估。对固定化酶的磁化、形态、大小、结构变化和热行为进行了描述。1.0每毫克超顺磁性壳聚糖纳米颗粒通过与京尼平形成的共价键固定+/-0.1g木聚糖酶。与游离酶相比，固定化木聚糖酶表现出热、pH和催化速度的改善，并且可以重复使用三次。酶固定化后得到了254 nm的异质聚集体。该固定化方法成功地保持了酶的热稳定性，对于在相关工业的苛刻温度条件下使用天然化合物如Fe3O4@Chitosan@Xylanase具有重要意义。
Enzymes are gradually increasingly preferred over chemical processes, but commercial enzyme applications remain limited due to their low stability and low product recovery, so the application of an immobilization technique is required for repeated use. The aims of this work were to produce stable enzyme complexes of cross-linked xylanase on magnetic chitosan, to describe some characteristics of these complexes, and to evaluate the thermal stability of the immobilized enzyme and its reusability. A xylanase was cross-linked to magnetite particles prepared by in situ co-precipitation of iron salts in a chitosan template. The effect of temperature, pH, kinetic parameters, and reusability on free and immobilized xylanase was evaluated. Magnetization, morphology, size, structural change, and thermal behavior of immobilized enzyme were described. 1.0 +/- 0.1g of xylanase was immobilized per milligram of superparamagnetic chitosan nanoparticles via covalent bonds formed with genipin. Immobilized xylanase showed thermal, pH, and catalytic velocity improvement compared to the free enzyme and can be reused three times. Heterogeneous aggregates of 254nm were obtained after enzyme immobilization. The immobilization protocol used in this work was successful in retaining enzyme thermal stability and could be important in using natural compounds such as Fe3O4@Chitosan@Xylanase in the harsh temperature condition of relevant industries.