Recent studies on enzyme-catalysed recycling and biodegradation of synthetic polymers

Abstract

Post-consumer plastic waste has reached levels that are dangerous for the environment and for human health, and its management now represents a big challenge. Plastic biodegradation and biorecycling emerges as an addition to the conventional plastic waste recycling methods. This review describes recent studies on enzyme-catalysed synthetic polymers biorecycling and biodegradation. The emphasize lies on the most successful cases as that of enzyme-catalysed depolymerisation of polyethylene terephthalate, using a specially engineered enzyme PET depolymerase, that has recently been developed into industrial technologies as well as on other recent promising discoveries of enzymes that are potentially capable of complete and controlled plastic degradation in mild conditions. The review also discusses polymer qualities that are causing diminished plastic biodegradation, and the protein engineering methods and tools to increase enzyme selectivity, activity and thermostability. Many fields of expertise have been used in the described studies, such as polymer chemistry, microbiology, mutagenesis, protein and process engineering. Applying this innovative interdisciplinary knowledge offers new perspectives for the environmental waste management and leads to a sustainable circular economy.

Keywords

• Synthetic polymers
• Plastic waste
• Biorecycling
• Enzyme catalysis
• Biodegradation
• Protein engineering