Structures of Reaction Products and Degradation Pathways of Aflatoxin B1 by Ultrasound Treatment

Ultrasound is an emerging decontamination technology with potential use in the global food processing industry. In the present study, we explored power ultrasound for processing aqueous aflatoxin B₁ (AFB₁). AFB₁ was degraded by 85.1% after 80 min of ultrasound exposure. The reaction products of AFB₁ were identified and their molecular formulae elucidated by ultra-high-performance liquid chromatography Q-Orbitrap mass spectrometry. Eight main reaction products were found, and their structures were clarified by parental ion fragmentation. Two degradation pathways were proposed according to the degradation product structures: One involved the addition of H• and OH• radicals, whereas the other involved H₂O₂ epoxidation and H•, OH•, and H₂O₂ oxidation of AFB₁. Ultrasound treatment significantly reduced AFB₁ bioactivity and toxicity by disrupting the C8=C9 double bond in the furan ring and modifying the lactone ring and methoxy group.