Fungi, Aflatoxins, and Cyclopiazonic Acid Associated with Peanut Retailing in Botswana

Abstract

Peanuts are important food commodities, but they are susceptible to fungal infestation and mycotoxin contamination. Raw peanuts were purchased from retail outlets in Botswana and examined for fungi and mycotoxin (aflatoxins and cyclopiazonic acid) contamination. Zygomycetes were the most common fungi isolated; they accounted for 41% of all the isolates and were found on 98% of the peanut samples. Among the Zygomycetes, Absidia corymbifera and Rhizopus stolonifer were the most common. Aspergillus spp. accounted for 35% of all the isolates, with Aspergillus niger being the most prevalent (20.4%). Aspergillus flavus/parasiticus were also present and accounted for 8.5% of all the isolates, with A. flavus accounting for the majority of the A. flavus/parasiticus identified. Of the 32 isolates of A. flavus screened for mycotoxin production, 11 did not produce detectable aflatoxins, 8 produced only aflatoxins B1 and B2, and 13 produced all four aflatoxins (B1, B2, G1, and G2) in varying amounts. Only 6 of the A. flavus isolates produced cyclopiazonic acid at concentrations ranging from 1 to 55 microg/kg. The one A. parasiticus isolate screened also produced all the four aflatoxins (1,200 microg/kg) but did not produce cyclopiazonic acid. When the raw peanut samples (n = 120) were analyzed for total aflatoxins, 78% contained aflatoxins at concentrations ranging from 12 to 329 microg/kg. Many of the samples (49%) contained total aflatoxins at concentrations above the 20 microg/kg limit set by the World Health Organization. Only 21% (n = 83) of the samples contained cyclopiazonic acid with concentrations ranging from 1 to 10 microg/kg. The results show that mycotoxins and toxigenic fungi are common contaminants of peanuts sold at retail in Botswana.

Risk assessment of aflatoxins in food products consumed in South Korea

“…Our result was supported by previous reports that the peanut is one of the most susceptible foodstuffs to be contaminated by toxicogenic fungi producing aflatoxins (Mphande 2004). Particularly, AFB 1 levels of peanut and pistachio were ranged from 0.11 to 88.04 µg kg -1 and from 3.36 to 38.66 µg kg -1 , respectively.…”

Avaliação da micoflora e ocorrência de micotoxinas em cascas de amendoim em diferentes estágios de maturação da vagem

“…Outros autores, estudando a microbiota fúngica do amendoim, relataram os gêneros Aspergillus spp., Fusarium spp. e Penicillium spp., como os principais contaminantes (MPHANE et al, 2004). A maior incidência da espécie A. flavus (49 %) foi constatada no estágio de granação dos frutos, seguido pelo fruto já maduro (8,8 %).…”

“…Sua contaminação pelos Aspergillus flavus e A. parasiticus, fungos produtores de aflatoxinas, pode ocorrer antes ou após a colheita (MPHANE et al, 2004). A espécie Aspergillus flavus pode, também, produzir o ácido ciclopiazônico que é um ácido indólico que ocorre naturalmente em produtos agrícolas, tais como, amendoim e milho e, muitas vezes, como um co-contaminante com as aflatoxinas (LISKER et al, 1993).…”

Determination of Aflatoxins in Medicinal Plants by High-Performance Liquid Chromatography–Tandem Mass Spectrometry

“…Signs of acute aflatoxicosis include depression, nervousness, abdominal pain, diarrhea and death (23). The aflatoxins occur widely in food, especially in corn, nuts, peanuts, coconut, fruits, dried fruits and beer (24,25). High moisture and temperature are two main factors that cause the occurrence of mycotoxins at pre-harvest and post harvest stages (26).…”