Cutinases for Biocatalytic Polycarbonate Hydrolysis: Empowering Circular Economy

Area of Science:

• Polymer Science
• Biotechnology
• Green Chemistry

Background:

• Synthetic polymers like polycarbonate (PC) are crucial but require sustainable recycling strategies.
• Conventional PC recycling methods often lead to quality degradation and are complicated by additives.
• Novel enzymatic approaches are needed for efficient and high-quality polymer recycling.

Purpose of the Study:

• To develop the first efficient enzymatic recycling process for polycarbonate (PC).
• To identify enzymes capable of hydrolyzing PC under mild conditions.
• To recover valuable monomers, specifically bisphenol A (BPA), from recycled PC.

Main Methods:

• Extensive screening of cutinases for hydrolytic activity against PC in aqueous buffer.
• Optimization of reaction conditions to maximize PC conversion.
• Investigation of co-solvent effects, specifically dimethyl sulfoxide (DMSO), on enzymatic hydrolysis.

Main Results:

• Nine cutinases demonstrated hydrolytic activity toward PC, enabling BPA recovery.
• Enzymes ThcCut1-ACCG and LCC-ICCG achieved 20-40% PC conversion under optimized conditions.
• Supplementation with 30% DMSO resulted in complete PC conversion.

Conclusions:

• Enzymatic hydrolysis offers a promising route for sustainable polycarbonate recycling.
• The identified cutinases and optimized conditions provide a foundation for industrial PC circular economy processes.
• This method facilitates the recovery of valuable BPA monomers, enhancing resource efficiency.