Abstract
Escalating concentrations of organic and inorganic pollutants continue to jeopardize global ecosystems, exposing the economic and environmental limitations of conventional physicochemical remediation. Enzymatic bioremediation—leveraging the selective catalytic power of oxidoreductases, hydrolases, and oxygenases—presents a sustainable alternative capable of degrading diverse contaminants under ambient conditions. Recent breakthroughs in directed evolution and protein engineering have significantly optimized the thermostability and kinetics of plastic-degrading enzymes, enabling efficient PET depolymerization near glass transition temperatures. Furthermore, metagenomic exploration of extreme environments has expanded the biocatalytic repertoire to include recalcitrant dyes, hydrocarbons, and halogenated xenobiotics. While challenges such as enzyme deactivation in complex matrices and transformation product toxicity persist, the integration of nanobiocatalysis, AI-guided design, and hybrid systems is accelerating industrial scalability. This review synthesizes these mechanistic and engineering milestones, providing a strategic roadmap for low-footprint remediation within a circular bioeconomy framework.