Effect of ozone treatment on aflatoxin B1 and safety evaluation of ozonized corn

This paper studies the ozone treatment effect on degradation of aflatoxin B-1 (AFB(1)) in corn with different moisture content (MC). The toxicity of the degradation products (DPs) of the ozone-treated AFB(1)-Contaminated Corn (ACC) was also evaluated using the human hepatocellular carcinoma cell line (HepG2) as model cells. The degradation rate of AFB(1) in corn increases with ozone concentration and treatment time. The results showed that ACC with 13.47% MC was easier to be degraded by ozone than with 20.37% MC. Treated with 90 mg L-1 ozone for 20 min and 40 min, AFB(1) in corn with 13.47% MC decreased from 83 mu g kg(-1) to 18.12 mu g kg(-1) and 9.9 mu g kg(-1), respectively, well meeting the China National Standard of AFB(1) in corn (20 mu g kg(-1)). In order to evaluate the safety of ozone used on ACC, the impacts of AFB(1) as well as untreated and ozone-treated ACC with the same level of AFB(1) content on HepG2's survival rate, morphology, and apoptosis were studied. The results showed that ACC had high cell toxicity while the toxicity of ozone-treated ACC had no significant difference with that of the AFB(1)-free culture solution. It is concluded that ozonation can quickly and effectively degrade AFB(1) in corn and diminish ACC's toxicity, and therefore, ozonation is expected to be an effective, fast, and safe method for AFB(1) degradation in ACC. (C) 2013 Elsevier Ltd. All rights reserved.