Mohamed Saleh A, Al-Ghamdi Saeed S, El-Shishtawy Reda M
Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia; Molecular Biology Department, National Research Center, Dokki, Cairo, Egypt.
Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
Int J Biol Macromol. 2016 Oct;91:663-70. doi: 10.1016/j.ijbiomac.2016.06.002. Epub 2016 Jun 2.
Horseradish peroxidase (HRP) was immobilized on amidoximated acrylic fabric after being activated with cyanuric chloride. FT-IR spectroscopy and scanning electron microscopy were used to characterize fabrics. The maximum immobilization efficiency of HRP (70%) was detected at 4% cyanuric chloride and pH 7.0. The immobilized enzyme retained 45% of its initial activity after ten reuses. The immobilization of enzyme on the carrier is saturated after 6h of incubation time. The pH was shifted from 7.0 for soluble HRP to 7.5-8.0 for the immobilized enzyme. The soluble HRP and immobilized HRP had the same optimum activity at 40°C. The immobilized HRP is more thermal stable than soluble HRP. Substrate analogues were oxidized by immobilized HRP with higher efficiencies than those of soluble HRP. Km values of the soluble HRP and the immobilized HRP were 31 and 37mM for guiacol and 5.0 and 7.8mM for H2O2, respectively. The immobilized HRP had higher efficiency for removal of phenol than that of soluble HRP. The immobilized HRP had higher resistance toward heavy metal ions compared to the soluble enzyme. The immobilized HRP was more stable against high concentration of urea, Triton X-100 and isopropanol. The immobilized HRP exhibited high resistance to proteolysis by trypsin than soluble enzyme. In conclusion, the immobilized HRP could be used as a potential efficient catalyst for the removal of aromatic pollutants from wastewater.
辣根过氧化物酶（HRP）经三聚氯氰活化后固定在偕胺肟化丙烯酸织物上。采用傅里叶变换红外光谱（FT - IR）和扫描电子显微镜对织物进行表征。在三聚氯氰浓度为4%、pH值为7.0时，检测到HRP的最大固定化效率为70%。固定化酶经十次重复使用后仍保留其初始活性的45%。酶在载体上的固定化在孵育6小时后达到饱和。pH值从可溶性HRP的7.0变为固定化酶的7.5 - 8.0。可溶性HRP和固定化HRP在40°C时具有相同的最佳活性。固定化HRP比可溶性HRP具有更高的热稳定性。底物类似物被固定化HRP氧化的效率高于可溶性HRP。可溶性HRP和固定化HRP对愈创木酚的Km值分别为31和37mM，对H2O2的Km值分别为5.0和7.8mM。固定化HRP去除苯酚的效率高于可溶性HRP。与可溶性酶相比，固定化HRP对重金属离子具有更高的抗性。固定化HRP对高浓度尿素、Triton X - 100和异丙醇更稳定。固定化HRP比可溶性酶对胰蛋白酶的蛋白水解作用具有更高抗性。总之，固定化HRP可作为一种潜在的高效催化剂用于去除废水中的芳香族污染物。
