bi.nlm.nih.gov){#intref0010}).

DON concentrations following the screen were measured by GC/MS following standard laboratory protocols ([@bib32]). Aliquots of 50 μL from each culture were dried down in a glass tube using compressed air in a nitrogen evaporator set at 55 °C. Dried samples were then derivatized at room temperature with a mixture of 99 μL of N-trimethylsilylimidazole (TMSI) and 1 μL of trimethylchlorosilane (TMCS) for 10 min. Then, 500 μL of isooctane containing 0.5 μg/g of mirex (Sigma-Aldrich, St. Louis, MO, USA) was added to the glass tube, followed by the addition of 500 μL of water to quench the reaction. Samples were vortexed thoroughly. From the top organic layer, 150 μL was transferred to chromatography vials for GC/MS analysis.

An Agilent 6890/5975 system was used for GC/MS analysis operating in selected ion monitoring (SIM) mode. An autosampler in split less mode injected 1 μL of each sample onto an HP-5MS column (0.25 mm inner-diameter, 0.25 μm film thickness, 30 m length) to detect DON. The inlet temperature was set at 280 °C with a column flow rate of 1.2 mL/min using helium. The initial column temperature was held at 150 °C for 1 min, increased to 280 °C at a rate of 30 °C/min, and held constant for 3.5 min. A post-run of 325 °C for 2.5 min was used to clean the column. DON was detected in SIM mode at a mass/charge ratio of 512.3 and had reference ions at 422.4 and 497.3. Mirex (hexachloropentadiene dimer) was used as an internal standard to check the quantitative precision of the instrument and was detected in SIM mode at a mass/charge ratio of 271.8 and had a reference ion of 275.8 ([@bib19]). A quadratic regression model was used to quantify DON with standards (Romer Labs, Austria and Sigma-Aldrich, St. Louis, MO, USA) at concentrations of 0.05, 0.10, 0.25, 0.5, 1.0, 2.50, 5.0 and 10.0 μg/mL.

2.5. Inhibition experiments {#sec2.5}
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A series of inhibition experiments were conducted to compare OD~600~ measurements of 