From structural complexity to circular applications: a comparative review of the enzymatic degradation of polydopamine, tannins, lignins, and melanins

Evidence from laboratory and animal studies provides groundwork for understanding mechanisms and potential before human studies continue.

• Level A · Stronger Clinical Evidence
• Level B · Emerging clinical evidence with positive signals
• Level C · Early human research exploring benefits
• Level D · Scientific groundwork from lab and animal studies
• Emerging · Emerging topic under active research

Abstract (original English)

Polydopamine, tannins, lignins, and melanins are diverse natural and bio-inspired polyphenolic materials known for their structural complexity, functional versatility, and growing technological importance. Their widespread presence in biological systems and emerging applications in coatings, packaging, biomedicine, and sustainable materials call for a deeper understanding of their biodegradation. This review presents a comparative analysis of their enzymatic breakdown, highlighting the roles of oxidoreductases, including laccases, peroxidases, and tyrosinases, in facilitating polymer depolymerization, structural modifications, and downstream valorization. Unique structural features such as catechol units in polydopamine, galloyl groups in tannins, phenylpropanoid backbones in lignins, and indole-quinone frameworks in melanins dictate their degradation rates and enzyme accessibility, presenting specific challenges and opportunities. Beyond biodegradation, this review situates these processes within the framework of potential recycling-by-design and a circular economy, demonstrating how controlled enzymatic conversion can produce high-value intermediates for green chemistry, biomaterials, energy recovery, and environmental remediation. By comparing these biopolymers side by side, we identify common principles, challenges, and technological opportunities to transform enzymatic deg

Evidence level

Evidence from laboratory and animal studies provides groundwork for understanding mechanisms and potential before human studies continue.

Browse all related research

Filter the research library by this study's title keywords, author, or publication year.