Garlic essential oil as an antifungal and anti-mycotoxin agent in stored corn

Abstract Corn kernels are highly susceptible to fungal and mycotoxin contamination. This study verified the effectiveness of garlic essential oil (GEO) to inhibit Aspergillus parasiticus, Fusarium verticillioides, and Gibberella zeae, producers of aflatoxin B1 (AFB1), fumonisin B1 (FB1), and zearalenone (ZEA), respectively, in stored corn kernels. The potential of the oil to interact with these mycotoxins and their bioaccessibility after swine simulated digestion was also evaluated. GEO showed minimum inhibitory concentrations (MICs) for A. parasiticus, G. zeae, and F. verticillioides of 0.0086, 0.069, and 0.0086 mg/mL, respectively, and minimal fungicidal concentrations (MFCs) four-fold greater than the MIC. Fungal growth was reduced completely by gaseous GEO at a range between 2 and 10 μL/L. The population of A. parasiticus and G. zeae was reduced to levels below the detection limit, whereas F. verticillioides had a 2.33 Log UFC/g reduction after 30 d of storage when contaminated corn kernels were treated with 1000 μL/L of GEO. GEO was not able to directly react with either AFB1, FB1, or ZEA in phosphate buffer or during simulated digestion. The results of our study confirmed that GEO can avoid the growth of mycotoxigenic fungi and, therefore, may be used to improve safety of stored corn kernels.