Current state and sustainable management of waste polyethylene terephthalate bio-disposal: enzymatic degradation to upcycling.

Poly (ethylene terephthalate) (PET) is a widely used plastic that leads to significant environmental pollution due to its durability. Enzymatic degradation of PET presents an eco-friendly disposal approach, with potential scalability for industrial applications. This review examines key crucial factors influencing PET enzymatic degradation, including the catalytic efficiency of PET hydrolase, production scalability of PET hydrolase, and recyclability of degraded PET. We outline major advancements in PET hydrolase development, including discovery techniques, functional enhancement strategies, and degradation optimization. Additionally, it assesses the preparation methodologies for PET hydrolase, covering bacterial expression systems, high-density fermentation technologies, and approaches for sustainable catalytic use. The review also discusses upcycling processes for PET hydrolysates, focusing on repolymerization into new plastics or bioconversion into valuable chemicals. Successful achievement of waste PET bio-disposal in industrial-scale n hinges on balancing degradation costs with revenue from upcycling products. Aim at this target, the review further points out the critical challenges, and proposes targeted solutions and expectations.