Hexavalent Chromium Removal Using Filamentous Fungi: Sustainable Biotechnology

To advance sustainable, safe biotechnologies for removal of heavy metals in industrial effluents, we evaluated two filamentous fungi isolated from chromium-contaminated soil (Aspergillus fumigatus and Cladosporium spp.) as well as three organisms obtained from a microorganism bank (Penicillium commune, Paecilomyces lilacinus and Fusarium equiseti). We tested the ability of these organisms to tolerate and remove Cr(VI) from effluents. The fungi showed visible morphological variations in growth after exposure to medium with traces of Cr(VI). In metal-removal assays (20 mg/L), efficiencies of 99% to 35% were observed, with the highest values for Cladosporium spp. Application in industrial effluent demonstrated removal efficiency of 58% for P. commune. These data suggest that these filamentous fungi have great potential for biological removal of heavy metals and may serve as an alternative to conventional systems.