Health Implication of Mycotoxigenic Fungi and Mycotoxins Analysed from Sun Dried Yam and Potato Chips Sold in Minna Niger State, Nigeria

Abstract

Mycotoxin is toxic secondary metabolite synthesized by filamentous fungi during their stationary phase of growth in agricultural crops, food and feed products. Niger State experienced high temperature and humidity for about three-quarters of the year, and these are some of the conditions that encourage filamentous fungi to produce mycotoxin in food products. Enzyme Linked Immunosorbent Assay (ELISA) was used to dectect mycotoxins. Mycological profile and mycotoxins of sun dried yam and potato chips was determined. Total of fifty (50) samples were collected randomly from five markets in Minna and its environs. 179 isolates were recorded. Aspergillus species 86(53.1 %) Mucor species 27(15.1 %), yeast species 25(13.9 %) Penicillium species 14(7.8 %), Fusarium species 14(7.8 %) Rhizopus species 3(1.7 %) and Microsporum species 1(0.6 %) were the common fungi. The highest mean fungal counts (12.8 x 103 cfu/g) were observed in sweet potato chips bought in Gwada market while the lowest (3.5 x 103 cfu/g), was observed in Yam chips from Paiko market. The mean moisture content of 7.41±2.28 % was recorded in potato chips and yam chips had the lowest moisture content of 4.72± 1.66 %. Total aflatoxins, fumonisin and zearalenone contents were detected in 48 (96 %) of the samples. In yam and potato chips, total aflatoxin contamination was 68 and 84 % with mean concentrations of 12.6±7.36 μg/kg and 10.3±13.81 μg/kg respectively. The total aflatoxin concentration range of yam and potato chips were 0-61.84 μg/kg and 0-54.49 μg/kg with 28 and 48 % of the samples below 4μg/kg E.U limit respectively. Fumonisin contamination was 80 and 60% with mean concentrations of 928.123±559.50 μg/kg and 722.64 ± 137.85 μg/kg with a range 0.0-4018.24 μg/kg and 0 – 2055.98 μg/kg and had 52 and 72 % below 1000 μg/kg acceptable limit for yam and potato chips respectively. Zearalenone contamination in yam and potato account for 56 and 68% having mean concentration of 16.33± 9.71 μg/kg and 24.12± 21.03 μg/kg with a range 0 – 45.53 μg/kg and 0 – 83.74 μg/kg respectively. All the samples contaminated with Zearalenone were below the E.U regulatory limit of 100 μg/kg for food stuff intended for direct consumption. Dietary exposure and risk characterisation (EDI and %TDI) were further estimated for total aflatoxins, fumonisin and zearalenone. It was concluded that the level of contamination of these chips with mycotoxins poses a serious threat to public health and there is the need for proactive approach to drastically reduce fungal contamination.