Introduction and objective: Scedosporium/Lomentospora species are human opportunistic filamentous fungi able to form biofilm in both biotic and abiotic surfaces.However, little is known about the ability of these fungi to release molecules into the biofilm environment. In this context, the present study aimed to detect hydrolytic enzymes, proteases and lipases, in the supernatants obtained from biofilm-forming cells of S. apiospermum, S. minutisporum, S. aurantiacum and L. prolificans (formerly S. prolificans).Materials and methods: Biofilms were formed through incubation of Scedosporium and Lomentospora conidial cells for 72 hours over a polystyrene surface and validated by classical biomarkers (biomass, extracellular matrix and viability). In parallel, the cell-free biofilm supernatants were harvested in order to measure the activity of secreted hydrolytic enzymes, proteases and lipases. Azoalbumin and azocasein were used as proteinaceous substrates, while 4-methylumbelliferyl butyrate, 4-methylumbelliferyl heptanoate and 4-methylumbelliferyl oleate were used as lipid substrates.Results: As previously reported, mature biofilms formed by Scedosporium/Lomentospora species were confirmed by the presence of a dense mycelial mass covering the polystyrene surface. Protease and lipase activities were detected in the biofilm-derived supernatants of all fungi studied. Regarding the protease, similar cleavages were observed for both azo-substrates, conjugated to albumin and casein, with an overall predilection to neutralalkaline pH range. Concerning the lipase, substrates containing lipids with small, medium and large carbonic chains were degraded, with different predilection according to the fungal species.The inferences: Collectively, the results suggest the presence of distinct proteases and lipases secreted by biofilm-growing cells of S. apiospermum, S. minutisporum, S. aurantiacum and L. prolificans.

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Background: Scedosporium/Lomentospora species are human pathogens resistant to almost all antifungals currently available in clinical practice. Methods: The effects of 16 1,10-phenanthroline (phen)/1,10-phenanthroline-5,6-dione/dicarboxylate chelates containing Cu(II), Mn(II) and Ag(I) against Scedosporium apiospermum, Scedosporium minutisporum, Scedosporium aurantiacum and Lomentospora prolificans were evaluated. Results: To different degrees, all of the test chelates inhibited the viability of planktonic conidial cells, displaying MICs ranging from 0.029 to 72.08 μM. Generally, Mn(II)-containing chelates were the least toxic to lung epithelial cells, particularly [Mn2(oda)(phen)4(H2O)2][Mn2(oda)(phen)4(oda)2].4H2O (MICs: 1.62–3.25 μM: selectivity indexes >64). Moreover, this manganese-based chelate reduced the biofilm biomass formation and diminished the mature biofilm viability. Conclusion: [Mn2(oda)(phen)4(H2O)2][Mn2(oda)(phen)4(oda)2].4H2O opens a new chemotherapeutic avenue for the deactivation of these emergent, multidrug-resistant filamentous fungi.