The Effect of Double Mutations in Aspergillus flavus

The pervasive presence of Aspergillus flavus in agricultural systems and its dual role as a facultative pathogen and saprophyte underscore its critical impact on food safety and human well-being. A major concern stems from its production of aflatoxins, toxins that contaminate food products and present severe health risks to consumers. To better understand A. flavus and its toxin production, this research focused on inducing double mutations using sodium azide and potassium chlorate. We subsequently characterized the phenotypic and metabolic profiles of these mutants, evaluating their growth patterns and antifungal resistance relative to the wild-type strain. Three wildtype strains (Aspfwt₁, Aspfwt₂ and Aspfwt₃) isolated previously in the laboratory were subcultured and subjected to double mutation. by subjecting the strains to mutagens (Potassium Chlorate and sodium azide) twice. Thus the mutants that were phenotypically different the wild type were generated through repeated culturing on mutagen-supplemented media, sodium azide demonstrating a stronger mutagenic effect at 0.12g/ml. The experiment on double mutation led to the development of mutants that differs from the wild in phenotypic, metabolic and growth characteristics. The results exhibited that the double mutation caused a significant alteration in the fungus’s growth rate, with the mutants exhibiting a higher growth rates than the wild strains. The mutation also increased the organism’s resistance to fluconazole, an antifungal agent. The mutation led to the formation of auxotrophic mutants that were unable to grow on minimal medium. When two of these mutants were combined in a plate with minmum medium, the progeny of the mutants resulted in a heterokaryon, showing a wildtype phenotype through complementation. The use of double mutation in this work which revealed the complexity of the genetics of A. flavus, has given insight into the development of novel antifungal agent. However, the need for molecular basis for a clear understanding of the interaction between double mutation and secondary metabolites production in the fungus is highlighted.