College of Food Science and Technology, Henan University of Technology, Zhengzhou, China.
J Sci Food Agric. 2023 Jan 30;103(2):792-798. doi: 10.1002/jsfa.12190. Epub 2022 Sep 19.
Aflatoxin B (AFB ) poses a severe threat to human and animal health. Countries worldwide have invested considerable manpower and material resources in degrading aflatoxins. Enzyme degradation is the most efficient and environmentally friendly approach for modifying aflatoxin into less toxic molecules. Catalase is commonly used as a detoxification agent to decrease the contamination levels of aflatoxins in animal feeds. This study aimed to obtain recombinant catalase via gene engineering and determined whether a recombinant catalase could degrade AFB .
The catalase gene (KatA) from Pseudomonas aeruginosa was cloned and expressed in Escherichia coli, and the expression conditions of this recombinant catalase were optimized. The recombinant catalase was isolated and purified using Ni-chelating affinity chromatography, and its ability to degrade AFB was evaluated. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the expressed of catalase was approximately 55.6 kDa, which was subsequently purified using Ni-chelating affinity chromatography. The degradation rate of AFB by recombinant catalase in the presence of syringaldehyde was 38.79%.
The degradation of AFB by a recombinant catalase has been reported for the first time. This study provides a new paradigm for the use of recombinant catalases in degrading AFB in food and feed. © 2022 Society of Chemical Industry.
黄曲霉毒素 B（AFB）对人类和动物健康构成严重威胁。世界各国投入了大量的人力和物力来降解黄曲霉毒素。酶降解是将黄曲霉毒素转化为毒性较低分子的最有效和最环保的方法。过氧化氢酶通常用作解毒剂，以降低动物饲料中黄曲霉毒素的污染水平。本研究旨在通过基因工程获得重组过氧化氢酶，并确定重组过氧化氢酶是否可以降解 AFB。
从铜绿假单胞菌中克隆并在大肠杆菌中表达了过氧化氢酶基因（KatA），并优化了该重组过氧化氢酶的表达条件。使用 Ni-螯合亲和层析法分离和纯化重组过氧化氢酶，并评估其降解 AFB 的能力。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳显示，过氧化氢酶的表达约为 55.6 kDa，随后使用 Ni-螯合亲和层析法进行纯化。在丁香醛存在下，重组过氧化氢酶对 AFB 的降解率为 38.79%。
首次报道了重组过氧化氢酶对 AFB 的降解作用。本研究为利用重组过氧化氢酶在食品和饲料中降解 AFB 提供了新的范例。 © 2022 化学工业协会。
