The relationship between ergosterol and mycotoxin contamination in maize from various countries

Abstract

Maize is a good substrate for fungal growth and production of toxic secondary metabolites or mycotoxins. The relationships between the fungal biomarker ergosterol (ERG) and mycotoxins such as aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA) were investigated in maize collected from four different geographic locations. ERG and mycotoxins were measured by high-performance liquid chromatography with UV and fluorescence detection. ERG did not correlate with AFs in 139 analysed samples. OTA contamination was found in only one sample from the North American region. A significant correlation (r (2) = 0.82) was observed between ERG and ZEA. AFs and ZEA were found in 47% of all samples. Half of the samples contained more than two mycotoxins. Levels of ERG and mycotoxin contamination differed by geographical region. North American and Asian samples had higher frequencies and levels of ERG and mycotoxin contamination. No AF contamination was observed in European samples (limit of detection 0.025 μg/kg for AFB1). We conclude that samples containing less than 3 mg/kg ERG in most cases do not exceed the EU maximum limits for AFs, OTA and ZEA.