A novel investigated method for decoupling adsorption and degradation effect on AFB1 based on isotope tracing and NMR analysis

Research on the biodegradation of AFB1 technology is a hot topic in food security, and screening microorganisms and determining their effectiveness are key. The existing methods for microorganism screening and effectiveness determination are generally based on the reduction of AFB1. When a coupling of adsorption and degradation occurs, the degradation is easily undetected or misunderstood, leading to incorrect resolution and utilization. In this study, a method of decoupling adsorption and degradation using isotope tracing and nuclear magnetic resonance (NMR) was explored and verified in a strain of Meyerozyma guilliermondii (AF01). The method used the generation of products instead of the AFB1 removal rate to determine the nature of the reaction. The products were traced by 13C17-AFB1, purified, and identified using NMR, liquid chromatography-mass spectrometry (LC-MS), high-performance liquid chromatography (HPLC), and ultraviolet (UV)-visible spectra. Finally, AF01 removed 95.55% of AFB1, among which 25.07% of AFB1 was degraded into aflatoxicol and epi-aflatoxicol.