Page 87 - University of Pretoria RESEARCH REVIEW 2018

From farm to fork –
contributing to food security
Neriman Yilmaz, Department of Biochemistry, Genetics and Microbiology, and FABI
Fungi are important for health and well-being at many levels. In the food supply chain, fungi are the cause
of much food spoilage and are thus a challenge for producers, suppliers, retailers and consumers alike.
Fungi not only contaminate
food and animal feed but also produce toxins that are dangerous to people and animals. These so-called mycotoxins are secondary metabolites produced by various genera of fungi, the most important being Aspergillus, Penicillium and Fusarium. Although more than 300 fungal toxins have been identified globally, only five
are classified as being of public
health or agricultural importance: aflatoxin, deoxynivalenol, zearalenone, fumonisin and ochratoxin A – the last two were discovered by South African researchers. Walter Marasas, for many years an honorary professor at UP, led the team on fumonisin work.
The identification of food and feed spoilage fungi using both traditional and molecular methods are important in food safety, and to maintain the quality of food and feed products from farm to fork. It is estimated that approximately 25% of global food
and feed output is contaminated by mycotoxins. This figure is higher for the African continent, in large part due to the lack of regulations, or where regulations exist, the lax or irregular enforcement thereof.
Dr Neriman Yilmaz, a senior postdoctoral fellow at the Department
of Biochemistry, Genetics and Microbiology and FABI, studies the taxonomy of the mycotoxigenic genus Fusarium. She works in the newly establishment Applied Food and Feed Mycology Programme at FABI with Professors Pedro Crous, Bernard Slippers and Cobus Visagie, exploring the biodiversity and phylogeny of fungi related to food and animal feed and the raw materials used in production.
In collaboration with GrainSA, the research team screens maize, soybean seeds, sunflowers seeds
and animal feed for the presence of Fusarium, Aspergillus and Penicillium. The data are then combined with mycotoxin levels detected in samples to determine the relationship between the presence of these species and
the mycotoxin levels. The team isolates and identifies fungi, describes novel species, and develops rapid identification techniques for the monitoring of the most important species.
Dr Yilmaz has described many new fungal species. Her latest research was published in MycoKeys where
she described a new synnematous Talaromyces from India. This study was undertaken in collaboration with the National Fungal Culture Collection of
Soybean seed with Aspergillus flavus, which produces aflatoxin.
India and Agriculture and Agri-Food Canada. In another international partnership with the Westerdijk Fungal Biodiversity Institute (WI) in the Netherlands, she has characterised almost 300 strains belonging to the Fusarium fujikuroi species complex (FFSC) using multigene sequencing, and discovered six novel species.
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