Potential of fungi in the biosorption of heavy metals present in acid mine tailings

Resumen

Heavy metal contamination from acid mine drainage is a major environmental threat due to the high mobility of elements such as copper, zinc, cadmium, and chromium under low pH conditions. This study analyzes the potential of different fungal species for the biosorption and neutralization of these metals, evaluating their behavior under conditions similar to acid mine drainage. Thirty studies published between 2015 and 2025 were compiled, identifying the genera Aspergillus, Penicillium, and Fusarium as the most efficient in metal retention and biotransformation. The results show that fungi develop complementary metabolic mechanisms, such as surface adsorption, intracellular bioaccumulation, and redox biotransformation (e.g., the reduction of Cr(VI) to Cr(III)), which contribute to metal immobilization and detoxification. Furthermore, the use of simple carbon sources (glucose, malt extract, molasses) and moderate aerobic conditions favor their metabolism and the expression of antioxidant enzymes. Removal efficiencies reached up to 95–99% in species such as Penicillium simplicissimum and Aspergillus niger. Overall, filamentous fungi are establishing themselves as a viable, sustainable, and economical biotechnological alternative for the remediation of tailings and acid mine drainage.