Cnidarian-derived filamentous fungi from Brazil: isolation, characterisation and RBBR decolourisation screening

Marine-derived fungi represent a valuable source of structurally novel and biologically active metabolites of industrial interest. They also have drawn attention for their capacity to degrade several pollutants, including textile dyes, organochlorides and polycyclic aromatic hydrocarbons (PAHs), among others. The fungal tolerance to higher concentrations of salt might be considered an advantage for bioremediation processes in the marine environment. Therefore, filamentous fungi were isolated from cnidarians (scleractinian coral and zoanthids) collected from the north coast of São Paulo State, Brazil. A total of 144 filamentous fungi were morphologically and molecularly characterised. Among them there were several species of Penicillium and Aspergillus, in addition to Cladosporium spp., Eutypella sp., Fusarium spp., Khuskia sp., Mucor sp., Peacilomyces sp., Phoma sp. and Trichoderma spp. These fungi were tested regarding their decolourisation activity for Remazol Brilliant Blue R (RBBR), a textile dye used as an initial screening for PAH-degrading fungi. The most efficient fungi for RBBR decolourisation after 12 days were Penicillium citrinum CBMAI 853 (100%), Aspergillus sulphureus CBMAI 849 (95%), Cladosporium cladosporioides CBMAI 857 (93%) and Trichoderma sp. CBMAI 852 (89%). Besides its efficiency for dye decolourisation within liquid media, C. cladosporioides CBMAI 857 also decolourised dye on solid media, forming a decolourisation halo. Further research on the biotechnological potential, including studies on PAH metabolism, of these selected fungi are in progress.