Esawy Mona A, Awad Ghada E A, Wahab Walaa A Abdel, Elnashar Magdy M M, El-Diwany Ahmed, Easa Saadia M H, El-Beih Fawkia M
Department of Chemistry of Microbial and Natural Products, National Research Centre, Tahrir Street, Dokki, Cairo, Egypt.
Centre of Scientific Excellence-Group of Encapsulation and Nanobiotechnology, Polymers Department, National Research Center, El-Behooth St., Dokki, Cairo, Egypt.
3 Biotech. 2016 Jun;6(1):29. doi: 10.1007/s13205-015-0333-2. Epub 2016 Jan 11.
A novel extreme halophilic exochitinase enzyme was produced by honey isolate Aspergillus awamori EM66. The enzyme was immobilized successfully on k-carrageenan-alginate gel carrier (CA) with 93 % immobilization yield. The immobilization process significantly improved the enzyme specific activity 2.6-fold compared to the free form. The significant factors influencing the immobilization process such as enzyme protein concentration and loading time were studied. Distinguishable characteristics of optimum pH and temperature, stability at different temperatures and NaCl tolerance for free and immobilized enzyme were studied. The immobilization process improved optimum temperature from 35 to 45 °C. The immobilized enzyme retained 76.70 % of its activity after 2 h at 75 °C compared to complete loss of activity for the free enzyme. The reusability test proved the durability of the CA gel beads for 28 cycles without losing its activity.
从蜂蜜中分离得到的泡盛曲霉EM66产生了一种新型极端嗜盐外切几丁质酶。该酶成功固定在κ-卡拉胶-海藻酸盐凝胶载体（CA）上，固定化产率为93%。与游离形式相比，固定化过程显著提高了酶的比活性，提高了2.6倍。研究了影响固定化过程的重要因素，如酶蛋白浓度和负载时间。研究了游离酶和固定化酶的最佳pH值和温度、在不同温度下的稳定性以及对NaCl的耐受性等显著特征。固定化过程将最佳温度从35℃提高到了45℃。与游离酶在75℃下2小时后完全失去活性相比，固定化酶在75℃下2小时后仍保留其76.70%的活性。重复使用性测试证明了CA凝胶珠在28个循环中具有耐久性，且不会失去其活性。
