Skip to main content
ARS Home » Pacific West Area » Maricopa, Arizona » U.S. Arid Land Agricultural Research Center » Pest Management and Biocontrol Research » Research » Publications at this Location » Publication #347869
Research Project: Improved Environmental and Crop Safety by Modification of the Aspergillus flavus Population Structure

Location: Pest Management and Biocontrol Research

Title: Aflatoxin contamination of dried wild fruits in Zambia

Author
item KACHAPULULA, PAUL - University Of Zambia
item BANDYOPADHYAY, RANAJIT - International Institute Of Tropical Agriculture (IITA)
item Cotty, Peter

Submitted to: Frontiers in Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/25/2019
Publication Date: 8/9/2019
Citation: Kachapulula, P.W., Bandyopadhyay, R., Cotty, P.J. 2019. Aflatoxin contamination of dried wild fruits in Zambia. Frontiers in Microbiology. 10. https://doi.org/10.3389/fmicb.2019.01840.
DOI: https://doi.org/10.3389/fmicb.2019.01840

Interpretive Summary: Aflatoxins are toxic fungal metabolites that can inhibit human development, cause cancer, and even induce death. Occurrence of these toxins greatly reduces the markets to which crops can be sold and the health of consuming populations. The fungi named Aspergillus flavus and A. parasiticus are the primary cause of aflatoxin contamination of several crops, insects and fish. In order to understand the epidemiology of contamination and the risk these fungi pose to human health and trade, aflatoxins were quantified and, and populations of A. flavus and A. parasiticus were examined in wild fruits from Zambia. Aflatoxins were detected in wild fruits. Aspergillus flavus and A. parasiticus were the most frequent fungi on wild fruits from Zambia. The current work suggests that consumption of wild fruits might result in human exposure to aflatoxins, and that aflatoxin mitigation is needed in wild fruits in Zambia.

Technical Abstract: Wild fruits are an important food and income source for many households in Zambia. Non-cultivated plants may be as susceptible as crops to aflatoxin contamination. Concentrations of aflatoxins in commonly consumed wild fruits from markets and characteristics of associated aflatoxin-producers need to be determined to assess the aflatoxin risk posed by handling, processing, storage, and consumption. Samples of Schinziophyton rautanenii (n = 22), Vangueriopsis lanciflora (n = 7), Thespesia garckeana (n = 17), Parinari curatellifolia (n = 17), Ziziphus spp. (n = 10), Adansonia digitata (n = 9), and Tamarindus indica (n = 23) were assayed for aflatoxin using lateral-flow immunochromatography from 2016 to 2017. Aflatoxins were above Zambia’s regulatory limit (10 mg/kg) in S. rautanenii (average = 57 mg/kg), V. lanciflora (average = 12 mg/kg), and T. garckeana (average = 11 mg/kg). The L strain morphotype of Aspergillus flavus was the most frequent member of Aspergillus section Flavi in market samples, although Aspergillus parasiticus and fungi with S morphology were also found. All fruits except T. indica supported both growth (mean = 3.1 108 CFU/g) and aflatoxin production (mean = 35,375 mg/kg) by aflatoxigenic Aspergillus section Flavi. Innate resistance to aflatoxin producers was displayed by T. indica. For the other fruits, environment and infecting fungi appeared to have the greatest potential to influence aflatoxin concentrations in markets. This is the first report of aflatoxins and aflatoxin-producers on native fruits in Zambia and suggests mitigation is required.