Fungi in global hydrocarbon bioremediation: biodiversity, enzymatic pathways and technological innovations

Fungi have emerged as powerful biological agents in the bioremediation of hydrocarbon-contaminated environments due to their robust enzymatic systems, adaptability, and ecological relevance. This review critically examines their potential, highlighting enzymatic mechanisms and technological innovations that underpin this sustainable approach. Case studies with: Aspergillus sp., Fusarium sp., Paecilomyces sp., Penicillium sp., and Trametes sp. demonstrate, through complex enzyme systems (laccases, lignin, manganese, and versatile peroxidases), the ability to degrade toxic compounds such as polycyclic aromatic hydrocarbons (PAHs) and BTEX, converting them into less harmful metabolites or even reusable by-products. Integrated strategies, including: biostimulation, bioaugmentation, microbial consortia, and the application of biosurfactants and bioemulsifiers, further enhance fungal efficiency in heterogeneous environments. Emerging innovations such as enzyme immobilization, myco-nanoremediation, and genetic engineering are discussed as promising solutions to overcome the inherent limitations of contaminant degradation under adverse conditions. Nevertheless, significant challenges remain, including the complexity of fungal metabolic pathways, gaps in proteomic regulation, and persistent obstacles in scaling and field reproducibility, which currently restrict large-scale commercial application. The alignment of fungal bioremediation with circular economy principles is emphasized, particularly the transformation of oil-derived pollutants into economically valuable bioproducts. Although fungal-based technologies remain underexplored commercially, especially in relation to regulatory frameworks and strategic partnerships, with this gap being especially evident in the Brazilian context, this review provides a robust foundation for advancing the application of fungi in sustainable environmental recovery. By integrating mechanistic insights with technological innovations and regulatory perspectives, it addresses a critical gap in the literature and outlines future directions for the field. This review uniquely integrates fungal bioremediation mechanisms with emerging technologies, highlighting enzyme immobilization and myco-nanoremediation. It addresses critical proteomic gaps that hinder scalability and field application, especially in hydrocarbon-polluted environments. It connects bioremediation to the principles of a circular economy by showcasing the various functions of fungi in breaking down hydrocarbons, absorbing heavy metals, and producing biosurfactants. Despite promising laboratory study results, it highlights the absence of commercial fungal technologies. It offers a pioneering outlook that bridges biochemical innovations and industrial deployment, especially within Brazil’s regulated framework, a perspective largely absent in recent global reviews.