Prevalence of fumonisin-producing fungi in maize (Zea mays) obtained from markets in the southern region of Nigeria

Aims: This study was aimed at detecting the presence and quantity of fumonisins in maize sold in different markets in southern Nigeria, thereby igniting our awareness of the dangers in their patronage. Methodology and results: The incidence of potential mycotoxin producers was determined on samples (n=60) of maize collected randomly from three different markets, each in six states in Southern Nigeria. The fungi were cultured using the direct plating method on potato dextrose agar and dichloran rose bengal chloramphenicol agar. Pure cultures (n=90) obtained were tentatively identified using cultural and morphological characteristics. Molecular identification was carried out by obtaining fungal DNA and the amplified DNA. Sequences of DNA were blasted against the nucleotide database of NCBI to identity the isolates. The fungal isolates identified belong to 10 genera, with Aspergillus and Fusarium had the highest number of occurrences, followed by Trichoderma. The highest amount of fumonisin (13.45 ppm) was produced by Fusarium verticilloides strain KN11 and the least amount of fumonisin (0.01 ppm) was produced by F. venenatum strain MNF5. Maize samples were found to contain varying degrees of fumonisin, with isolates from Cross River State having the highest percentage. Conclusion, significance and impact of study: The contamination of food by fumonisin is a severe threat to disease outbreaks worldwide. Results highlight a food safety risk that the government need to monitor and educate consumers. More emphasis should be given to the application of nanotechnology and genetic engineering in developing resistant varieties of crops to ensure the safety and quality of food for future generations.