Isolation and characterization of Bacillus velezensis YM1 and its mechanism for zearalenone degradation
Jiangtao Feng, DU Xiao-yan, Yuying Zhang, Yuqing Xie, Yanxia Cong, Junbo He, Weinong Zhang
Abstract
Zearalenone (ZEA) is a hazardous mycotoxin that extensively contaminates food and feed, posing critical health risks to humans and animals. Microbial degradation is a promising approach for eliminating ZEA. In this study, a strain YM1 possessing efficient ZEA degradation activity was isolated from moldy corn, and identified as Bacillus velezensis YM1 ( B. velezensis YM1). B. velezensis YM1 exhibited significant ZEA degradation rates ranging from 91.6 % to 98.3 % within a wide range of temperatures 16 – 50 °C and pH values 4 – 10, indicating that strain YM1 possesses superior heat and pH tolerance. B. velezensis YM1 showed a ZEA degradation rate of 86.4 % in corn samples. Extracellular enzymes secreted by strain YM1 in the culture supernatant are primarily responsible for ZEA degradation. Moreover, potential degradation products of ZEA were identified through liquid chromatography-mass spectrometry analysis, leading to an infered degradation pathway. The result suggests that B. velezensis YM1 degrades ZEA by cleaving the lactone ring structure. Finally, cytotoxicity assessments indicate that the degradation products have lower toxicity compared to the original ZEA. These findings indicate that B. velezensis YM1 holds significant potential in the ZEA eliminating from food and feed. • A strain YM1 with ZEA degradation activity was isolated and identified as Bacillus velezensis. • Bacillus velezensis YM1 possesses excellent heat tolerance (16 – 50 °C) and pH tolerance (4 – 10). • It was that extracellular enzymes in the culture supernatant are responsible for ZEA degradation. • The degraded products of ZEA were identified via LC-MS analysis, leading to an inferred pathway for ZEA degradation. • The ZEA degradation products exhibit much lower toxicity compared to the original ZEA.