Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
Int J Biol Macromol. 2020 Dec 15;165(Pt B):2049-2059. doi: 10.1016/j.ijbiomac.2020.10.081. Epub 2020 Oct 18.
Composite polycaprolactone-chitosan material was produced by an electrospinning method and used as a support for immobilization of tyrosinase by mixed ionic interactions and hydrogen bonds formation. The morphology of the fibers and enzyme deposition were confirmed by SEM images. Further, multivariate polynomial regression was used to model the experimental data and to determine optimal conditions for immobilization process, which were found to be pH 7, temperature 25 °C and 16 h process duration. Under these conditions, novel type of biocatalytic system was produced with immobilization yield of 93% and expressed activity of 95%. Furthermore, as prepared system was applied in batch experiments related to biodegradation of bisphenol A under various remediation conditions. It was found that over 80% of the pollutant was removed after 120 min of the process, in the temperature range 15-45 °C and pH 6-9, using solutions at concentration up to 3 mg/L. Experimental data collected proved that the stability and reusability of the tyrosinase were significantly improved upon immobilization: the immobilized biomolecule retained around 90% of its initial activity after 30 days of storage, and was still capable to remove over 80% of bisphenol A even after 10 repeated uses. By contrast, free enzyme was able to remove over 80% of bisphenol A at pH 7-8 and temperature range 15-35 °C, and retained less than 60% of its initial activity after 30 days of storage.
采用静电纺丝法制备了壳聚糖/聚己内酯复合纤维材料，利用离子间混合相互作用和氢键形成将其作为固定化酪氨酸酶的载体。通过 SEM 图像证实了纤维的形态和酶的沉积。此外，还使用多元多项式回归对实验数据进行建模，以确定固定化过程的最佳条件，结果发现最佳条件为 pH 7、温度 25°C 和 16 h 过程持续时间。在此条件下，固定化产率为 93%，表达活性为 95%，获得了新型的生物催化体系。此外，在所制备的体系中，在各种修复条件下进行了双酚 A 生物降解的批实验。结果发现，在 15-45°C 温度范围和 pH 6-9 条件下，使用浓度高达 3mg/L 的溶液，经过 120min 的处理，超过 80%的污染物被去除。收集的实验数据证明，固定化显著提高了酪氨酸酶的稳定性和可重复使用性：固定化生物分子在储存 30 天后保留了其初始活性的 90%左右，并且即使在 10 次重复使用后，仍能够去除超过 80%的双酚 A。相比之下，游离酶在 pH 7-8 和 15-35°C 温度范围内能够去除超过 80%的双酚 A，并且在储存 30 天后保留了不到 60%的初始活性。
