Evaluation of Aflatoxin Contamination in Zea mays (Maize) Sold in Katsina Central Market, Nigeria

Abstract

This study was carried out to isolate moulds and detect Aflatoxin in maize sold in Katsina Central Market. A total of ten (10) samples of maize were collected from five different vendors in the market and subjected to mould isolation, Aflatoxin extraction and characterization of the toxin type using Thin Layer Chromatography (TLC). Four fungal genera namely Aspergillus, Penicillium, Fusarium and Rhizopus species were isolated from 7(70%), 1(10%), 3(30%) and 7(70%) of the samples respectively. Aspergillus species were the predominant species isolated with Aspergillus flavus occurring in 7(70) and Aspergillus niger 6(60) of the total samples. Extraction of the toxin was carried out using methanol and water while type of the toxin was determined using thin layer chromatography (TLC), in which blue fluorescence on the TLC plates in 7(70%) indicated the presence of aflatoxin B in the samples. Retention factor (RF) value with a range of 0.40-0.60 was calculated using the standard formulae. The research suggest proper harvesting, drying, storage and public enlightenment to avoid contamination  and consumption of maize grains infested by the number one carcinogenic toxin.