This paper aimed to evaluate the contamination with mycotoxigenic fungi and total aflatoxins in stored corn from different sites in Puebla and Tlaxcala, Mexico. Methodology. The study was conducted at two sites in Puebla (San Salvador El Seco and Junta Auxiliar La Resurrección) and two sites in Tlaxcala (Tlaltepango and Nativitas). A total of 80 samples of stored corn were collected. Identification of Aspergillus flavus was performed by microculture techniques and specific taxonomic keys (macromorphological and micromorphological). Then, samples of contaminated corn were selected, and aflatoxin production was confirmed using a direct solid-phase ELISA kit. A total of 25 A. flavus strains were identified. Other possible mycotoxin-producing fungi were Penicillium (n=52) and Fusarium (n=19). Regarding total aflatoxin contamination, all samples were contaminated within a range of 1.589 to 11.854 μg/kg, and the average concentration was 6.3 μg/kg corn. Implications. The detection of mycotoxigenic fungi in the samples tested and of aflatoxins in corn highlights the importance of monitoring these fungi. Since food safety is at risk, it shows the need for methods to control these fungi and their metabolites.

The primary goal of this research is to isolate mycotoxin-producing fungus from the Nagavali River. Examining isolated fungi involved analyzing their mycelium growth on culture media and detailed microscopic inspection. We employed PCR analysis utilizing universal primers ITS1 and ITS4 to accurately identify the species. Furthermore, we sequenced the amplified ITS region and rigorously analyzed the sequences using NCBI-BLASTn and the ITS2 database. The analysis found a high 96.38% genetic similarity to the Aspergillus flavus strain, resulting in a 600-base pair fragment size. The sequence was given the accession number OR536222 in the NCBI GenBank database. Phylogenetic analysis was performed to ascertain the particular strain of A. flavus and its source. Remarkably, this analysis led to the identification of a single new strain gene, which represents a novel discovery in the field of fungal research. These results underscore the vital significance of molecular techniques in promptly and precisely identifying organisms. This research enhances our understanding of mycotoxin contamination in water, providing valuable insights to improve detection and prevention strategies. It accentuates the overarching importance of conserving our water resources and upholding ecological equilibrium, ultimately safeguarding the well-being of both humanity and the environment.