Relative severity of fumonisin contamination of cereal crops in West Africa

Abstract

Traditional and improved varieties of maize, pearl millet and sorghum were planted by small-scale farmers under the direction of the International Institute for Tropical Agriculture in two Nigerian agro-ecological zones: the Sudan Savanna and the Northern Guinea Savanna. Samples were collected for the determination of Fusarium infection and fumonisin (B1, B2 and B3) contamination. A previous paper reported Aspergillus infection and aflatoxin contamination of these samples. Fusarium infection levels, measured by per cent kernels infected, were modest with mean levels for the above cereals of 16% ± 11% (SD), 12% ± 7% and 13% ± 16%, respectively. However, the Fusarium species recovered from maize were predominantly the fumonisin producers F. verticillioides and F. proliferatum, together making an infection rate of 15% ± 10%, whereas these species were present to a limited extent only in the other two cereals, 1% ± 1% for pearl millet and 2% ± 6% for sorghum. Fumonisin contamination was variable but reflected the diversity of Fusarium producers in these three cereals. Mean levels were 228 ± 579 µg kg(-1) (range < 5-2860 µg kg(-1)) for maize, 18 ± 7 µg kg(-1) (range = 6-29 µg kg(-1)) for pearl millet and 131 ± 270 µg kg(-1) (range < 5-1340 µg kg(-1)) for sorghum. Together with previous results on aflatoxin, this study confirmed the co-occurrence of aflatoxins and fumonisins in maize as well as in the traditional African cereals, millet and sorghum (89% co-occurrence across all three cereals). The low fumonisin levels may be ascribed to the use of good agricultural practices. Of the Fusarium species present, those in maize consisted mainly of fumonisin producers, the opposite of what was observed in pearl millet and sorghum. It is concluded that replacement of maize by pearl millet and sorghum could improve food safety with regards to aflatoxin B and fumonisin B exposure.

Traditionally Processed Beverages in Africa: A Review of the Mycotoxin Occurrence Patterns and Exposure Assessment

“…Other mycotoxins, including DON, NIV, OTA, and ZEN, were also reported at low levels in Ethiopian sorghum (Chala and others ). Lower levels of FUM were recorded in sorghum from Nigeria compared to maize (Vismer and others ; Chilaka and others ). Furthermore, no OTA, FUM, or DON was detected in sorghum grains from Cameroon (Djoulde ).…”

“…According to Chilaka and others (), maize, and millet had higher FUM, DON, and ZEN contaminations than sorghum in Nigeria, most of which exceeded the maximum regulatory limit of 1000 μg/kg set for the sum of FB 1 and FB 2 by the EU (FAO ). Interestingly, pearl millet and finger millet, which are also used in preparing traditional beverages, especially in West and East Africa, were less susceptible to mycotoxin contamination as they had very low levels of AFB 1 (Chala and others ) and FUM (Nyangi ; Vismer and others ). It is thought that ZEN is the most common mycotoxin in both sorghum and finger millet (Chala and others ).…”

“…At present, there is no information on mycotoxin contamination in other grains such as sorghum and finger millet and banana used in making traditional beverages in Eastern Africa. Although there are limited data on cereals other than maize, such foods seem to be less susceptible to AFs and FUM contamination (Bandyopadhyay and others ; Vismer and others ).…”

Major mycotoxins occurrence, prevention and control approaches

“…From the African perspective, aflatoxins, ochratoxins, and fumonisins are considered to be widespread in major dietary and export oriented crops (Vismer et al, 2015). Even if the proportion is different, research by Ayalew (2002) revealed that ochratoxins, fumonisins and aflatoxins dominantly occur in Ethiopia.…”

Visual detection of Fusarium proliferatum based on asymmetric recombinase polymerase amplification and hemin/G-quadruplex DNAzyme

“…7 There are many reports on the illnesses of livestock and humans caused by Fusarium mycotoxins. [8][9][10] Methods based on qPCR have been developed for F. proliferatum detection. 11 Although they show high accuracy, these methods require expensive instruments and skilled operators; they are also limited by many factors, such as electric power, high cost, and long testing times, which results in inability to apply these methods outside the lab.…”