Microbial Consortia for Accelerated Degradation of Recalcitrant Plastics: A Review

Abstract

The increasing accumulation of man-made plastic in the environment constitutes one of the most urgent types of ecological problems of the 21st century. Now that more than 400 million tons of plastic are produced every year and only around 9% of the total plastic ever created has been recycled, it is necessary to adopt new biodegradation methods. Microbial consortia—cooperative communities of bacteria, fungi, and other microorganisms—have emerged as a promising biotechnological approach for the accelerated degradation of recalcitrant plastics, including polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). Unlike single-organism approaches, consortia leverage metabolic division of labor, synergistic enzymatic cascades, and cross-feeding interactions to overcome the biochemical recalcitrance of synthetic polymers. This review synthesizes recent advances in the identification, design, and engineering of plastic-degrading microbial consortia. Key enzymatic mechanisms are discussed, including the roles of PETase, MHETase, laccases, manganese peroxidases, alkane hydroxylases, and cutinases. The review further examines natural consortia isolated from plastic-contaminated environments, insect gut microbiomes, and engineered synthetic microbial communities designed through rational metabolic engineering and synthetic biology tools. Challenges related to scalability, environmental safety, regulatory considerations, and the gap between laboratory performance and real-world applicability are critically evaluated. Future directions, including the integration of computational modeling, machine learning-guided enzyme engineering, and hybrid chemo-biological upcycling strategies, are outlined. This review underscores the transformative potential of microbial consortia as an eco-friendly, sustainable solution for mitigating global plastic pollution.