Uranium phosphate mineral adsorption to newly isolated fungus Cladosporium sp. strain F1

It is necessary to develop environmentally benign methods for removing uranium from various environments due to its high toxicity and radioactivity. Among the methods, we used fungal biosoprtion using newly isolated Cladosporium sp. strain F1. Extensive absorption of presynthesized nanoplates of uranium-phosphate minerals was observed on the hyphae of the Cladosporium sp. strain F1. In addition, once soluble UO₂²⁺ species was added to the culture of Cladosporium sp. strain F1, uranium mineral plates were also observed on the surface of the fungus hyphae over a range of pH. This was confirmed by EDX analyses, and SEM, AFM, and thin sectional TEM image analyses. The maximum biosorption capacity of uranyl ions was 74.3 mg g⁻¹ at pH 6.0. In general, biosorption capacity of Cladosporium sp. strain F1 was better than that of Aspergillus niger strain to uranium minerals. In conclusion, this study showed that the newly isolated fungus Cladosporium sp. strain F1 could be a cost-effective and environmentally friendly biosorbent to remove toxic uranium from aqueous environments.