Biotechnology-enabled plastic valorization across enzymatic, microbial, and hybrid conversion systems: A review

Area of Science:

• Biotechnology
• Chemical Engineering
• Materials Science

Background:

• Plastic valorization is shifting towards carbon-retentive biotechnology.
• Enzyme discovery, protein engineering, and hybrid processing advance polymer conversion.
• Inconsistent terminology and metrics blur degradation vs. value-retentive conversion.

Purpose of the Study:

• Develop a systems framework for biotechnology-enabled plastic valorization.
• Integrate enzymatic, microbial, insect-derived, and hybrid processing approaches.
• Address challenges in feedstock complexity and performance benchmarking.

Main Methods:

• Review and synthesize advances in enzymatic depolymerization, microbial assimilation, and hybrid processing.
• Develop a systems framework integrating diverse biotechnological platforms.
• Conduct quantitative benchmarking to compare polyester and polyolefin transformation efficiencies.

Main Results:

• A performance divergence exists between polyester (near-closed-loop recovery) and polyolefin transformation (oxidative activation).
• Feedstock complexity, like dyes, necessitates detoxification and modular processing.
• Hybrid systems increase substrate accessibility but add complexity and energy demands.

Conclusions:

• Effective plastic conversion hinges on controlled carbon routing, not just breakdown.
• Biotechnology offers a programmable strategy for carbon management in plastic waste.
• Research priorities include polyolefin activation, scalable reactors, and techno-economic alignment for industrial biomanufacturing.