Reduction of Aflatoxin Levels in Corn Through Fermentation with Aspergillus niger and Rhizopus oligosporus

Abstract

Aflatoxin contamination in corn presents significant risks to feed safety and animal performance, emphasizing the importance of effective control methods such as fermentation with Aspergillus niger and Rhizopus oligosporus to lower toxin levels. The study aimed to evaluate the effects of initial aflatoxin levels, microbial fermentation type, and their interaction on the concentration of aflatoxin in ground corn following fermentation. An experimental approach was employed using a two-factor completely randomized design. The first factor consisted of aflatoxin levels (38.53 and 88.06 μg/kg), while the second factor comprised microbial treatments: non-fermented control, Aspergillus niger (0.25%), and Rhizopus oligosporus (0.25%). Fermentation was conducted for 60 hours, and Aflatoxin concentration was analyzed using LC-MS/MS. Statistical analysis revealed that both aflatoxin level and fungal treatment significantly affected (P<0.01) AFB1, AFB2, and total aflatoxin content in ground corn. Higher initial contamination (88.06 μg/kg) resulted in greater residual aflatoxin compared to the lower level (38.53 μg/kg). Fermentation with Aspergillus niger and Rhizopus oligosporus markedly (P<0.05) reduced AFB1, AFB2, and total aflatoxin to very low levels (<1–1.33 μg/kg), while the control treatments retained high toxin concentrations. A significant interaction (P<0.05) between aflatoxin level and fungal type indicated that detoxification efficiency depended on both initial contamination and the fermenting microorganism. Overall, fermentation with A. niger and R. oligosporus proved to be an effective biological approach for reducing aflatoxin levels in ground corn. Therefore, fermentation can be considered a promising biological approach for mitigating aflatoxin contamination in corn.