Microbial Contaminants and Aflatoxin Level in Indigenous Okra (Abelmoschus esculentus), Bologi (Senecio biafrae) and Ugwu (Telfairia occidentalis) from Two Selected Markets in Oyo State, Nigeria

Abstract

Farm product are majorly consumed globally, however, their level of contamination from microbes and aflatoxins from fungi species is worrisome. This study aimed to study the microbes and aflatoxin level in Okra (Abelmoschus esculentus), Ugwu (Telfairia occidentalis) and Bologi (Senecio biafrae) from two selected markets (Bodija and Ojoo) in Oyo State. Thirty (30) fresh samples of Okra, Ugwu and Bologi were purchased from the study area. Microbiological examination was carried out using standard microbiological procedures, aflatoxin quantification was assayed using High Performance Liquid Chromatography while aflatoxigenic potential of the fungal isolates was carried out on neutral red desiccated coconut agar. The result revealed the presence of six bacterial isolates (Proteus mirabilis, Micrococcus luteus, Klebsiella pneumonia, Streptococcus spp., Bacillus cereus and Salmonella sp.) and four (4) fungal isolates (Aspergillus niger, Aspergillus parasiticus, Cladosporium sp. and Rhizopus sp.) in the samples. The highest level of aflatoxin was observed in dried okra (14.000 µg/kg) from Bodija Market, while the lowest level was found in fresh Ugwu (0.001 µg/kg) from Ojoo Market. AFB1 was detected in all samples except for the fresh and dry Ugwu from Ojoo Market and the dry Ugwu from Bodija Market. Additionally, AFB2 was found in all samples. The non-aflatoxigenic fungi included Aspergillus niger found in okra from Ojoo Market, Aspergillus flavus in Ugwu from Bodija Market, and Aspergillus parasiticus in Ugwu from Ojoo Market. In contrast, Aspergillus parasiticus in okra from Bodija Market is aflatoxigenic. In conclusion, the vegetables investigated from the selected markets are contaminated with bacteria and fungi, except for Bologi, and aflatoxigenic fungus was identified in okra from Bodija Market.