Isolation and Molecular Detection of Aflatoxin-Gene from Fungi Isolated from Stores' Maize

Abstract

Zea mays (Maize) are grains susceptible to fungal attack in the field and during storage. The fungi may cause economic losses at all levels of the food and feed production chain through the production of secondary metabolites known as aflatoxins. Aflatoxins are various poisonous carcinogens and mutagens that are produced by certain molds, particularly Aspergillus flavus, Aspergillus nomius and Aspergillus parasiticus. They mostly affect grains such as maize, groundnut, peanut, rice and millet. This study aimed to isolate the suspected fungal species from maize grains obtained from market stalls/warehouses in Gombe Metropolis and screen them for mycotoxin production. A total of 150 samples were collected from selected stalls and the Gombe State Government warehouse and were inoculated onto potato dextrose agar (PDA), kept for seven days. The fungal species were identified using an atlas. Aflatoxin coding gene was detected through DNA extraction and amplification by polymerase chain reaction (PCR), followed by Gel Electrophoresis and UV illumination. Out of the 150 samples collected for the analysis, 20 were positive for Aspergillus species, only 10% (n=3) of the samples were positive for the Aspergillus flavus, Aspergillus nomius and Aspergillus parasiticus and the remaining 90% (n=27) were negative, indicating a prevalence distribution of species. Thus, the relevant authorities should take urgent measures to curb the spread of these pathogenic fungi to safeguard the lives of the populace.