The determination of zearalenone levels in wheat flour of bakeries in Khorramabad city by high performance liquid chromatography

Zearalenone is an estrogenic mycotoxin produced by several Fusarium species and is of particular interest because of its widespread occurrence and strong estrogenic effects. Wheat and its flour is amongst the most important food and feeds sources that may become contaminated with zearalenone. Therefore, this study was carried out to determine the zearalenone concentration in wheat flour. After extraction of zearalenone from wheat flour samples with extraction solvent acetonitrile - water, toxin purification step was conducted using immunoaffinity columns. Samples were analyzed by HPLC using C18 column (250 mm × 4.6 mm ID, 5µm) with a fluorescence detector, mobile phase of acetonitrile-water (3:2 v/v) at flow rate of 1ml/min. Results of the study showed that the level of found zearalenone in 5% of the samples was higher than maximum level of 200 μg/kg. The mean concentration of zearalenone in samples was 54 µg/kg. LOD and LOQ of this method were 3.5 and 10 ng/g respectively. Although the mean concentration of zearalenone in investigated wheat flour samples was lower than the maximum level recommended by the Codex Alimentations, but high incidence of zearalenone in these samples indicates the need for improving storage conditions in order to reduce the incidence and level of zearalenone contamination in samples