Exploring Fungal Biodegradation Pathways of 2,4-D: Enzymatic Mechanisms, Synergistic Actions, and Environmental Applications

2,4-D (2,4-dichlorophenoxyacetic acid) is one of the most widely used herbicides globally, effectively controlling broadleaf weeds in various agricultural systems. However, its persistence in the environment and potential health risks raise significant concerns, demanding efficient and sustainable detoxification strategies. This review critically examines the fungal biodegradation of 2,4-D, with a specific focus on the enzymatic pathways mediated by laccases, manganese peroxidases, and lignin peroxidases─key oxidative enzymes involved in the transformation of chlorinated aromatic compounds. Laccases initiate degradation by oxidizing phenolic structures and generating phenoxy radicals, while peroxidases contribute through the generation of reactive oxygen species that facilitate the cleavage of stable C–Cl and C–C bonds. The synergistic activity of these enzymes enhances degradation efficiency and expands the range of metabolizable compounds. Additionally, we explore the influence of environmental factors─such as pH, temperature, and nutrient availability─on enzymatic activity and stability. The review also discusses potential applications of intermediate metabolites, including their valorization in pharmaceutical and agrochemical industries. By integrating recent experimental findings and mechanistic insights, this work provides a comprehensive overview of fungal enzymatic systems for 2,4-D degradation and highlights their potential in advancing bioremediation strategies.