Multi-residue mycotoxin analysis of dry distillers grains
Distillers grains (DG) are the still residues after the ethanol has been collected. Approximately 90% of US production is used in domestic animal feed. Any Mycotoxins present in the fresh corn can be concentrated by a factor of three. Contamination can also occur during storage. This raises concern about the potential animal and human health hazards from the use of Mycotoxincontaminated distillers grains. Corn entering the ethanol processing plant as well as distillers grains should be routinely tested for Mycotoxin contaminations to ensure compliance with guidelines set by FDA.
We present a single screen method to cover 4 families of toxins that could be present in dry distillers grains (DDG).
Sample Extraction and Clean Up
25 g of finely grounded sample is extracted with 150 mL of water/Methanol mixture (30/70). 20 mL of filtered extract is diluted with 70 mL of Phosphate Buffered Saline (PBS). Aflatoxins, Zearealenone and OchratoxinA are isolated using AOZ Immunoaffinity column (Vicam, USA) according to the procedure from the column manufacture. Toxins are eluted with 2 x 2 mL of Methanol. Fumonisins are isolated using FumoniTest Immunoaffinity column (Vicam, USA) according to the procedure from the column manufacture. Toxins are eluted with 2 x 1.5 mL of Methanol and combined with eluant from AOZ column. Solution is evaporated to 0.5 mL and final volume is adjusted to 1 mL with Methanol.