Can ozone fumigation effectively reduce aflatoxin B₁ and other mycotoxins contamination on stored grain?

Abstract

Mycotoxins are secondary metabolites produced by filamentous fungi that have deleterious effects on human and animal consumers. Cereals are probably the most important source of intake of mycotoxins, because they are susceptible to fungal attack either in the field or during storage and consequently contaminated by mycotoxins under adverse conditions favouring fungal invasion and growth. As a powerful oxidant, ozone has been successfully used for controlling stored-product pests, fungi, and sometime degrading mycotoxins in solution or in vitro (present as pure standards). Despite the above fact, information on the use of gaseous ozone as a mycotoxin-degradation agent for cereal grain preservation is still very limited. Also, it is not clear whether ozone fumigation can effectively degrade mycotoxins on stored grains. In the paper, we put forward wet method of ozone fumigation to degrade mycotoxin contamination on stored grains, and compared the degradation efficacy of three ozone gas treatments-dry method, wet method and aqueous method on aflatoxin B₁ and other mycotoxins in grains. Our results showed that the wet method of ozone fumigation could better degrade mycotoxin-spiked grain sample than the dry method, and aqueous method also had a good mycotoxin-degradation efficacy. To our knowledge, it is the first time to specially report the wet method of ozone fumigation to degrade mycotoxins on stored grains.

Keywords: Ozone gas, Mycotoxin degradation, Stored grain, Wet method