Fungal Bioleaching for Metal Recovery: Recent Progress and Technological Advances

Fungal bioleaching, as a green and sustainable technology for metal recovery, demonstrates unique advantages in addressing growing global metal demand and utilizing secondary resources. This review systematically summarizes recent progress and technological advances in fungal bioleaching for metal recovery. Fungi solubilize metals through three core mechanisms, acidolysis, complexolysis, and redoxolysis, mediated by organic acids (citric, oxalic, gluconic), while cell wall functional groups enable biosorption. Most frequently used genera in modern bioleaching (Aspergillus, Penicillium, Trichoderma) have achieved remarkable recoveries from e-waste (Cu, Li, Co up to 100%), rare earth elements (consortia up to 76%), tailings, and spent catalysts. Optimization of key parameters (pH, temperature, pulp density) and application of intelligent strategies (response surface methodology, machine learning) have further enhanced leaching efficiency. Strain engineering and synthetic biology offer new avenues for constructing hyper-efficient strains. Despite remaining bottlenecks such as slow kinetics and scale-up difficulties, fungal bioleaching holds broad industrial prospects for advancing the circular metal economy and the green metallurgical transition.