Mycobiota and Aflatoxin Contaminations of Some Spices and Condiments Sold in Katsina Central Market, Nigeria

Abstract

Spices and condiments get contaminated with fungi and aflatoxin due to poor agricultural and storage practices. A total of 42 dried, raw, powdered and processed samples representing fourteen different types of spices and condiments were randomly collected in new polythene bags from Katsina central market (Katsina town) and were screened for fungi and aflatoxin contaminations. These were Clove, African nutmeg, Ashanti pepper, Candlewood, Ethiopian pepper, Pineapple of the bush, Ginger, Garlic, Chillies, Kajiji, Thyme, Chilli powder (yaji), Curry, and Locust bean (Dadawa). Fungi was isolated on Potato Dextrose Agar by Agar plate method for dried and raw samples and Standard Dilution Plate method for powdered samples. Enzyme-linked Immunosorbent Assay (ELISA) was used for aflatoxin determination. Ten fungal spp were isolated and identified as Aspergillus flavus, A. parasiticus, A. fumigatus, A. versicolor, A. niger, Mucor hiemalis, Rhizopus stolonifer, Phoma glomerata, Penicillium citrinum and Nigrospora sphaerica. Percentage occurrence of fungal species ranged from 1.8% for Nigrospora sphaerica to 35.7% for A. parasiticus. Eight out of 14 spices and condiments (57.1%) contained total aflatoxin ranging from 0.7–>20 µg/kg. Two of these (14.2%), namely clove (>20 µg/kg) and ginger (11.6 µg/kg), had aflatoxin levels above the maximum acceptable limit of 10 µg/kg set by the European Union and National Agency for Food and Drug Administration and Control and are therefore not safe for human consumption.