Second African Symposium on Mycotoxicology International collaboration yields results

by Dr Gert van Coller

MMycotoxins are toxic secondary metabolites produced by certain fungi, mostly from the genera Aspergillus, Fusarium and Penicillium

The five most important mycotoxins globally are aflatoxin, ochratoxin, deoxynivalenol (DON), zearalenone (ZEA) and fumonisin (FUM). DON and ZEA are produced by Fusarium graminearum and Fusarium pseudograminearum, which causes Fusarium head blight (FHB) and Fusarium crown rot (FCR) of wheat (see photos). Mycotoxins accumulate in food and animal feed and can be detrimental to human and animal health. Climate change is expected to result in shifts in mycotoxin-producing fungi and mycotoxin levels in food and feed, with an increase in mycotoxin contamination expected in some regions. According to the BIOMIN Research Centre (Tulln, Austria), the global risk level of mycotoxin contamination has increased over the course of 2016, especially in the EU, South America, and South Africa. More people have been affected by the consumption of mycotoxin-contaminated food in Africa than anywhere else. Increasingly effective government regulations and routine monitoring of food supplies have reduced the detrimental effect of mycotoxins in developed countries, but the reality is much bleaker in less-developed countries, where factors like food shortages are a reality.

Mycotoxicoses of farm animals present a further problem to the African continent. Agricultural crops produced in Africa have also been prevented from entering international markets, because of restrictions on mycotoxin levels imposed by regulatory authorities. On this topic, a lack of legislation regarding acceptable levels of mycotoxins exist in most African countries. Until 2016, South Africa only had legislation for acceptable levels of aflatoxins and patulin (a mycotoxin often found in apple products), although legislation has since been introduced that limits the amount of DON in maize and wheat, and FUM B1 and B2 in maize.

In an effort to address the threat of mycotoxins for the African continent, the African Mycotoxin Network was established in 2011. This culminated in the 1st African Symposium on Mycotoxicology, held in Zambia in 2015, where the African Society for Mycotoxicology was officially established. Following the success of the first symposium, the 2nd African Symposium on Mycotoxicology was held in June 2018 at the Leisure Lodge Beach and Golf Resort in Mombasa, Kenya, under the auspices of the International Society for Mycotoxicology (ISM). The symposium was attended by delegates from 12 African countries (see photo), as well as from European countries and the USA. The South African delegation comprised delegates from the Agricultural Research Council (ARC), the Southern African Grain Laboratory, Cape Peninsula University of Technology (CPUT), UNISA, and the universities of North-West, Stellenbosch, Cape Town and Johannesburg. The Western Cape Department of Agriculture was represented by the author of this article, Dr Gert van Coller.

The symposium was organised into six sessions, with a total of 50 papers and 22 posters presented. Session themes included continental and international collaboration on mycotoxin research, monitoring and evaluation of technology uptake in Africa, mycotoxin-detection methods for Africa, mycotoxin management in an African context, occurrence and importance of mycotoxins in African crops, and pre-harvest management. A major issue in Africa centres on affordability and the implementation of control strategies. This was a recurring theme throughout the symposium. In line with this, Dr Van Coller presented a 15-minute oral presentation entitled “Resistance in South African wheat cultivars and test lines to Fusarium head blight caused by F. graminearum s.s. and F. pseudograminearum” in the session, “Mycotoxin Management in an African Context”.

Results of a number of collaborative projects between African and European countries presented at the symposium are testimony to the progress made in addressing the mycotoxin problem in Africa. Indeed, the first keynote lecture presented at the symposium was entitled “Case studies for international collaborations: the key to detect, control and reduce mycotoxins in the food chain”, delivered by the president of the ISM, Prof. Rudolf Krska from Austria. In line with this, Dr van Coller had fruitful discussions with people like Prof. Krska and Prof. Sarah de Saeger from Ghent University in Belgium on the detection of mycotoxins in stubble used for animal feed.

Budget restraints limited the attendance of the symposium by delegates, especially from African countries, and this will be addressed in future. The symposium provided an excellent opportunity for researchers working with mycotoxins on the African continent to showcase their research, and for delegates to meet and exchange information. The next symposium will be held in Cape Town in 2021. AP