Mycotoxin Laboratory Projects:

Diagnosis of mycotoxin contamination of grains in Costa Rica

 In Costa Rican rice and beans are staple foods, and to a lesser extent, maize, peanut and other grains are consumed. These grains are a rich substrate for fungal growth and spoilage by Aspergillus and Fusarium species in the field, at harvest and during storage. In addition to causing possible yield losses, these fungi produce highly toxic secondary metabolites called Aflatoxins (produced by Aspergillus species) and fumonisins (produced by Fusarium species). These toxins pose a threat to human health because consumption of grain contaminated with aflatoxins and fumonisins has been associated with different types of cancer, among other problems they cause to human and animal health. At the national level there are only regulations for aflatoxins (maximum levels of 20 ug/kg for grains and 15 ug/kg peanuts) and no control over the levels of other important toxins is performed. Moreover, monitoring of aflatoxins is performed only in imported grains. Therefore, the objective of this research is to determine the level of mycotoxin contamination (aflatoxins and fumonisins) in grain intended for human consumption in Costa Rica.

Aspergillus species isolated from dry bean and their capacity to produce aflatoxins (Phaseolus vulgaris L.)

 Dry beans are a staple food in Costa Rica. During storage, bean quality can be reduced by many different microorganisms including Aspergillus species that have the ability to contaminate grains with aflatoxins, secondary metabolites that have been related to human liver cancer and other health issues in humans and animals. If storage conditions favor fungal growth, grain contamination with aflatoxins will depend on the Aspergillus species. Therefore, the objective of this research is establish an Aspergillus isolate collection, and to determine the ability of the isolates to contaminate beans with aflatoxins.