Evaluation of the Degradation Effect of Zearalenone in feed by Bacillus amyloliquefaciens H6 and its Detoxification in Mice.

The mycotoxin zearalenone (ZEN), which poses a threat to both human and animal health, is frequently detected in food and feed. Bacillus amyloliquefaciens H6 has been screened and identified as a functional microorganism capable of biodegrading ZEN in the previous studies. The degradation ability of the bacterium towards zearalenone and its derivatives in feed, as well as its protective effect in vivo, remains to be determined. Therefore, degradation tests were conducted on ZEN and its derivatives using bacterial fermentation broth to detoxify moldy feed. Furthermore, protection experiments were performed on mice fed with ZEN using the same fermentation broth. The results demonstrated that the fermentation of Bacillus amyloliquefaciens H6 effectively detoxified moldy feed with an initial concentration of 436.74 μg/kg of ZEN, leading to a significant decrease in its toxin content to 81.53 μg/kg Moreover, it exhibited degradation activity towards ZEN derivatives including α-zearalenol, β-zearalenol and α-zearalanol. Bacillus amyloliquefaciens H6 alleviated the weight loss triggered by ZEN exposure in mice while reversing alterations observed in relative mRNA expression levels associated with serum biochemical markers (ALT, AST, ALP), hepatic oxidative stress indicators (SOD, GSH-Px, CAT, MDA), and Nrf-2 signaling pathway (Nrf-2, HO-1, γ-GCs, GSH-Px). These effects collectively counteract oxidative damage inflicted by ZEN on mouse liver. The Bacillus amyloliquefaciens H6 strain exhibited a mitigating effect on hepatic and small intestinal pathological damage, surpassing the ZEN group in comparison. The cecal anaerobic flora structure was effectively reshaped, leading to significant alterations in microbial composition.