Detoxification of aflatoxin B1 by H2SO3 during maize wet processing, and toxicity assessment of the transformation product of aflatoxin B1

Maize is susceptible to contamination with aflatoxins (AFs). Consumption of AFs contaminated maize can cause poisoning and even death. The goals of this study were to determine the detoxification efficacy of sulfurous acid (H2SO3) on aflatoxin B1 (AFB1) within the range of soaking parameters used in industrial maize production, to identify the transformation product of AFB1 and analyze the cytotoxicity of transformation product. AFB1 contaminated maize was soaked in different concentrations of H2SO3 and the results indicated that soaking time and temperature could significantly influence the detoxification efficiency; 25-31 mu g/kg of AFB1 in maize could be detoxified by 0.2-0.3 % of H2SO3. The transformation product was obtained using mass spectrometry and molecular formula analysis. It was identified as C17H14O9S, named as AFB1-HSO3. The toxicity of AFB1-HSO3 was evaluated. Cell morphology showed that the damage caused by AFB1 was significantly greater than that caused by AFB1-HSO3. It also found that the effects of AFB1-HSO3 on the activity, ATP and DNA content of Hep G2 cells were significantly less than that of AFB1. It was concluded that AFB1-HSO3 was less toxic than AFB1 in this system. These results suggest that H2SO3 can be used as a potential detoxification agent in industrial maize production.

Automated summary

This study evaluated the detoxification efficacy of sulfurous acid on aflatoxin B1, identified the transformation product AFB1-HSO3, and analyzed its cytotoxicity. High temperature and high concentration of sulfurous acid could significantly degrade AFB1, and the toxicity of the transformation product AFB1-HSO3 was found to be lower than AFB1.