Engineering Laccase from Aspergillus terreus HNGD-TM15 with Enhanced Catalytic Activity and Thermostability for the Degradation of Aflatoxin B 1 and Zearalenone

Mycotoxin contamination poses a significant hazard to feed safety and animal health. Fungal laccases have shown promise in mycotoxin degradation; however, their practical application remains limited due to insufficient catalytic efficiency and thermostability. In this study, a laccase (AsLac) from Aspergillus terreus HNGD-TM15 demonstrated potential for degrading aflatoxin B1 (AFB1) and zearalenone (ZEN). To enhance its performance, protein fusion technology was employed to construct a fusion enzyme, S1v1-AsLac. Compared to AsLac, S1v1-AsLac exhibited a 49% improvement in AFB1 degradation and an 81% enhancement in ZEN degradation, along with a 2.02-fold extension in half-life at 60 °C, and improved storage stability. S1v1-AsLac effectively reduced AFB1 and ZEN levels in contaminated feed samples, achieving degradation rates of 66.05% and 79.60% for corn flour and 62.61% and 69.43% for corn bran, respectively. These results present a promising approach for enhancing laccase performance and highlight potential for the degradation of mycotoxins in contaminated feed.