A limited survey of zearalenone in Indonesian maize-based food and feed by ELISA and high performance liquid chromatography

A survey of zearalenone (ZON) in Indonesian maize-based food and feed was performed in 89 samples using an enzyme-linked immunosorbent assay (ELISA). Results indicated that 32 samples (36.0%) were contaminated in a range from 5.5 to 526 μg/kg. Only one highly contaminated sample was observed in a category of home-made food samples (>500 μg/kg) and the highest percentage of contaminated samples (>85.7%) was noted in a category of poultry feed. The positive samples based on the ELISA analyses were then confirmed using a high performance liquid chromatography (HPLC) method in combination with an immuno-affinity column for clean-up. Prior to sample measurement, the HPLC method was validated using a blank maize matrix. The overall average recovery of blank maize spiked with ZON at levels of 200-750 μg/kg were 100.2%. Detection limit based on a signal-to-noise ratio 3:1 was 3.0 μg/kg for ZON in maize samples and the linear range applicable for analyses was 5-900 μg/kg of ZON. Of 32 samples confirmed by HPLC, 25 samples were observed to be contaminated in a comparable range from 6.9 to 589 μg/kg. Comparative analysis of 25 positive samples using the ELISA and HPLC methods showed a reasonable correlation (R2=0.9258).