In vitro inhibition of toxigenic filamentous fungi

In vitro inhibition of toxigenic filamentous fungi by Pichia sp. and Debaryomyces sp. isolates from coffee (coffea arabica) fruits. Coffee is a national product with great importance for the Brazilian economy. The excessive use of pesticides led to research for alternative forms, such as biological control. The objective of this work was to assess the potential antagonistic effect of yeast in dual-culture with filamentous fungi. Isolates of Debaryomyces hansenii (UFLACF 889 and UFLACF 847) and Pichia auomala (UFLACF 710 and UFLACF 951) species were inoculated (10(3) to 10(6) celulas mL(-1)) with three species of filamentous fungi, Aspergillus ochraceus, A. parasiticus and Penicillium roqueforti (10(3) to 10(6) spores mL(-1)). The assessment of mycelial growth and counting of spores was done for 21 days. It was observed that the isolated UFLA CF 889 attained, on average, the greatest inhibitory effect on the spore production of A. ochraceus (inhibition of 82%) and P. roqueforti (74%). The isolated UFLA CF 710 inhibited the spore production, on average, 60 and 75.6% of A. ochraceus and P. roqueforti, respectively. The fungus A. parasiticus was the most resistant to inhibition by yeasts. The mycelial growth was not inhibited by the presence of yeast in dual-culture. It could be concluded that yeast in dual-cultiure with filamentous fungi were able to inhibit the production of spores and potentially reduce the spread of this fungus during coffee processing.