Profiling of Aspergillus species’ metabolites in maize using different analytical approaches

Abstract

Mycotoxin contamination of food has become a global food safety issue mainly as a result of climate change. Mycotoxin estimation is crucial for their management plan as it is difficult to manage what cannot be quantified. Choosing the right analytical technique in mycotoxin quantification is essential in acquiring accurate data as mycotoxins occur in minute concentrations. Good, feasible and sensitive techniques are therefore needed for mycotoxin detection at such minute concentrations. The aims of this work are to compare the efficiency of HPLC and LC-MS/MS techniques for mycotoxin detection as well as assess the diversity of Aspergillus mycotoxins in maize. One hundred and twenty-three maize samples were analyzed using the HPLC and the LC-MS/MS techniques. Both methods had acceptable LOD, LOQ as well as recovery rates. Secondary metabolites such as 3-Nitropropionic acid and sterigmatocystin which are of safety concerns were detected in South African maize among others. Aspergillus species could be producing other unfamiliar metabolites that are uncounted for that might be underestimated contributors of toxicity to humans and animals. The co-occurrence of multiple toxins in food matrices requires multi-analyte detection techniques, therefore both methods will be suitable for monitoring maize quality, as the HPLC is suitable for the detection of major mycotoxin while LC-MS/MS for minor metabolites.