Reduction of fumonisin B1 and zearalenone by lactic acid bacteria in fermented maize meal.

Fusarium species are fungi that infect maize products worldwide and elaborate mycotoxins, which have been associated with cancer. This study was carried out to investigate the potential of lactic acid bacteria fermentation in reducing mycotoxin concentration and toxicity in maize meal products. Maize meal was spiked separately with fumonisin B1 and zearalenone and then allowed to ferment for 4 days. The potential cytotoxicity of the mycotoxin-spiked fermented extracts was also investigated using the SNO human esophageal carcinoma cell line (the SNO cell line was explanted from a cancer patient, S.N., a 62-year-old Zulu man, in July 1972). A significant decrease (P < 0.05) in the concentration of the two mycotoxins was observed, with a 56 to 67% and a 68 to 75% reduction in the third and fourth days, respectively. The two mycotoxins were not detectable in commercially fermented maize meal (amahewu) samples. After fermentation, mycotoxin-spiked maize meal samples containing lactic acid bacteria culture were comparatively less toxic to SNO cells than were samples without lactic acid bacteria. However, this difference in toxicity was not significant (P > 0.05). These results indicate that lactic acid bacteria fermentation can significantly reduce the concentration of mycotoxins in maize. However, such a reduction may not significantly alter the possible toxic effects of such toxins. The exact mechanism of toxin reduction warrants further investigation.