Preliminary screening of toxigenic fungi and mycotoxin contamination : a case of agricultural products in Ivory Coast

Abstract

Toxigenic fungi are generally known to contaminate agricultural products; the causes, rate, and extent of its effects on common products have less emphasis, especially in sub-Saharan African countries. This lack of emphasis could be attributed to the state of research, storage, and accountability that could have intimated the public with necessary measures to curb the menace.

For the purpose of the food safety control, this study investigates the fungal presence and mycotoxins in major food crops such as cereals (millet, rice, white and yellow maize), vegetables (chili, gnangnan, haricot, melon, and okra), legumes (haricot), and root products (attieke, cassava flakes) in Abidjan, Ivory Coast. Each sample is serially diluted and inoculated onto Czapek yeast agar (CYA), malt extract agar (MEA) and potato dextrose agar (PDA), to screen for fungal contamination. Colony color, colony edge, mycelia color, conidia shape, and microscopic features are used to identify the isolates. In addition, thin layer chromatography (TLC) was used to identify seven mycotoxins in food commodities. It is revealed that, Aspergillus species are found in 64 (92%) of the samples, Penicillium species in 29 (41%), and Fusarium species in 20 (29%) of the samples. A significant incidence rate of aflatoxin B1 (AFB1) is found in vegetables (gnangnan, haricot, and melon), roots products (cassava flakes), cereals (rice, and white maize). According to this investigation, each sample contains one or more fungus and mycotoxins.