Fungal population, including Ochratoxin A producing Aspergillus section Nigri strains from Ivory Coast coffee bean

Reduction in Ochratoxin A Occurrence in Coffee: From Good Practices to Biocontrol Agents

Ochratoxin A (OTA) is a mycotoxin mainly produced by Aspergillus section Circumdati and section Nigri across the coffee chain. OTA is nephrotoxic and is a threat to human health. This review summarizes current knowledge on how to reduce OTA concentration in coffee from farm to cup. After a brief introduction to the OTA occurrence in coffee, current good management practices are introduced. The core of this review focuses on biocontrol and microbial decontamination by lactic acid bacteria, yeasts and fungi, and their associated enzymes currently reported in the literature. Special attention is given to publications closest to in vivo applications of biocontrol agents and microbial OTA adsorption or degradation agents. Finally, this review provides an opinion on which future techniques to promote within the coffee supply chain.

Biocontrol activities of yeasts or lactic acid bacteria isolated from Robusta coffee against Aspergillus carbonarius growth and ochratoxin A production in vitro

Biocontrol Agents (BCAs) can be an eco-friendly alternative to fungicides to reduce the contamination with mycotoxigenic fungi on coffee. In the present study, different strains of bacteria and yeasts were isolated from Ivorian Robusta coffee. Their ability to reduce fungal growth and Ochratoxin A (OTA) production during their confrontation against Aspergillus carbonarius was screened on solid media. Some strains were able to reduce growth and OTA production by 85 % and 90 % and were molecularly identified as two yeasts, Rhodosporidiobolus ruineniae and Meyerozyma caribbica. Subsequent tests on liquid media with A. carbonarius or solely with OTA revealed adhesion of R. ruineniae to the mycelium of A. carbonarius through Scanning Electron Microscopy, and an OTA adsorption efficiency of 50 %. For M. caribbica potential degradation of OTA after 24 h incubation was observed. Both yeasts could be potential BCAs good candidates for Ivorian Robusta coffee protection against A. carbonarius and OTA contamination.

A review of toxigenic fungi and mycotoxins in feeds and food commodities in West Africa

Fungal contamination is a threat to food safety in West Africa with implications for food and feed due to their climate, which is characterised by high temperatures and high relative humidity, which are environmental favourable for fast fungal growth and mycotoxin production. This report gives perspective on studies on toxigenic fungi (Aspergillus, Fusarium and Penicillium) and their toxins, mainly aflatoxins, fumonisins and ochratoxins commonly found in some West African countries, including Benin, Burkina Faso, Gambia, Ghana, Ivory Coast, Mali, Nigeria, Senegal, Sierra Leone, and Togo. Only four of these countries have mycotoxins regulations in place for feeds and food products (Ghana, Ivory Coast, Nigeria, and Senegal). Food commodities that are widely consumed and were thoroughly investigated in this region include cereals, peanuts, cassava chips (flakes), cassava flour, chilies, peanuts, locust beans, melon, and yam products. In conclusion, authorities and scientists needed to consider research and approaches to monitor mycotoxins in foods and feeds produced and consumed in West Africa.