Polymeric nanoparticles (PNPs) are highly valuable across various industries due to their advantageous properties, including biocompatibility and enhanced release control, which are particularly important for pharmaceutical and cosmetic applications. Fungi, through secondary metabolism, are capable of producing biosurfactants (BSs)—amphiphilic molecules that reduce surface tension and can therefore substitute synthetic surfactants in PNP stabilization. In this study, we investigated the production of biosurfactants by the endophytic fungus Aspergillus welwitschiae CG2-16, isolated from the Amazon region, as well as its use as a PNP stabilizer. The fungus exhibited a 36% reduction in the surface tension of the culture medium during growth, indicative of BS production. The partially purified biosurfactant demonstrated an emulsification of 24%, a critical micelle concentration (CMC) of 280 mg/L, and an FTIR spectrum suggesting a lipopeptide composition. The biosurfactant was employed in the synthesis of poly-ε-caprolactone (PCL) nanoparticles via nanoprecipitation and emulsion/diffusion methods. Nanoprecipitation yielded spherical nanoparticles with a low polydispersity index (0.14 ± 0.04) and a high zeta potential (−29.10 ± 8.70 mV), indicating suspension stability. These findings highlight the significant role of biosurfactants in polymeric nanoparticle formation and stabilization, emphasizing their potential for diverse applications in pharmaceutical, cosmetic, and other industrial sectors.

Fungi have historically played a significant role in advancing biotechnology and are now increasingly recognized as flexible platforms for eco-friendly nanoparticle production. Nonetheless, progress has been hindered by inconsistent methodologies, limited mechanistic understanding, and reproducibility issues. Unlike earlier reviews, this study comprehensively analyzes a decade of research (2015–2025) to link fungal species diversity, biosynthesis pathways, and experimental setups to nanoparticle formation. It highlights the crucial roles of enzymatic activity and secreted metabolites in determining nanoparticle shape and stability. The study demonstrates that variables such as culture medium, pH, incubation period, and downstream processes are not minor technical details but key factors influencing nanoparticle size, morphology, and stability. Additionally, there is a strong taxonomic bias toward a narrow set of filamentous fungi and a material bias toward silver, gold, and zinc, despite the broader biosynthetic potential of the fungal kingdom and the growing relevance of unexplored metals, including critical metals (e.g., Nb, Zr, and V). By combining mechanistic insights with advanced transcriptomic, proteomic, metabolomic, and genomic data, myconanotechnology can move toward a predictive framework based on metal stress responses, secreted biomolecules, and redox metabolism. Achieving this shift is critical to improving reproducibility, scaling up production, and developing rational approaches to the creation of fungal nanomaterials for biomedical, environmental, and industrial applications.

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.