Inhibitory action of mycocins on airborne fungi isolated from neonatal ICU

Airborne fungi, with the ability to establish themselves and contaminate the air, reduce the life quality of the organisms that circulate there. Invasive fungal nosocomial infections have progressively emerged as a relevant source of morbidity and mortality in patients, especially the immunosuppressed patients. The broad spectrum of antimicrobial activity and the great stability led to the use of Wickerhamomyces anomalus as a biocontrol agent, since it could be classified as a low-risk microorganism. The aim of the present study was to evaluate the inhibition of airborne fungi isolated in a Neonatal ICU by mycocins produced by W. anomalus. The mycocins containing W. anomalus culture supernatant showed β-glucanases activity of 4.2 U/mg. For fungal monitoring and inhibition test in solid environment, the passive sedimentation technique was used. The test consisted of a control plate containing Sabouraud Dextrose Agar, and another composed of culture medium and W. anomalus mycocins supernatant. Then, after incubation, the growth and/or inhibition of the collected fungi was observed. The growth of 15 genera was observed on the control plates: Aureobasidium spp., Curvularia spp., Emmonsia spp., Geotrichun spp., Fusarium spp., Rhizopus spp., Rhodotorula spp., Scedosporium spp., Chrysosporium spp., Trichoderma spp., Alternaria spp., Aspergillus spp., Acremonium spp., Penicillium spp. and Cladosporium spp. Cladosporium spp. was the most incident in the analyzed period, 40% (86 UFC). Meanwhile, on the test plates there was no growth of microorganisms. As a result, we can see the potential of W. anomalus mycocins in the development of new antimicrobial substances.