Effect of tannic acid binding on the thermal degradation behavior and product toxicity of boscalid

Abstract

The effect of tannic acid (TA) binding on the thermal degradation of boscalid was studied in this work. The results revealed that TA binding has a significant impact on boscalid degradation. The degradation rate constant of bound boscalid was reduced, and its corresponding half-life was significantly prolonged compared to the free state. Four identical degradation products were detected in both states through UHPLC-Q-TOF-MS, indicating that degradation products were not affected by TA binding. Based on DFT and MS analysis, the degradation pathways of boscalid included hydroxyl substitution of chlorine atoms and cleavage of CN and CC bonds. The toxicity of B2 and B3 exceeded that of boscalid. In summary, the binding of TA and boscalid significantly affected the thermal degradation rate of boscalid while preserving the types of degradation products. This study contributed to a fundamental understanding of the degradation process of bound pesticide residues in complex food matrices.