Occurrence of Aflatoxigenic Fungi in Smoke-dried Fish Sold in Jos Metropolis

Abstract

This research was conducted to determine the occurrence of aflatoxigenic fungi in smoke-dried fish at marketing centers in the Jos metropolis. Total fungal load per sample was derived from plate counts and expressed as colony-forming units per gram of sample (cfu/g). In-vitro aflatoxigenicity of mould isolates was evaluated on coconut extract agar by exposing reverse side of plates to 365 nm ultra violet light. The results show that mean fungal load of smoke-dried fish ranged between 2.00x103±8.49x102 to 3.09x104±8.85x103cfu/g. Generally, the processed fish was contaminated with combinations of eight fungal genera: Fusarium, Aspergillus, Saccharomyces, Penicillium, Mucor, Rhodotorula, Schizosaccharomyce, Acremonium and Rhizopus. Strains of Penicillium digitatum, Fusarium equiseti and Fusarium semitectum were the most predominant at 61.67%, 30.00% and 26.67% respectively. Comparatively, the assessment shows that smoke-dried fish from Terminus were the most contaminated (P < 0.05) followed by samples from Chobe and Katako markets. Out of 164 fungal isolates, only strains of Aspergillus flavus 5(8.33%) from Terminus market exhibited aflatoxin producing potential. In view of sea food safety and quality, the presence of toxigenic fungi on smoke-dried fish is of health significance and increase the risk of mycotoxin poison. The findings of this study call for stiff regulation and monitoring of smoke-dried fish in our open markets.