High performance persistent organic pollutants removal using stabilized enzyme aggregates over amino functionalized...

Area of Science:

• Environmental Science
• Biotechnology
• Materials Science

Background:

• Persistent organic pollutants (POPs) pose significant environmental and health risks.
• Conventional water treatment methods often struggle with the complete removal of recalcitrant pollutants.
• Enzyme-based biocatalysts offer a promising alternative for efficient and sustainable pollutant degradation.

Purpose of the Study:

• To develop a highly efficient and recyclable biocatalyst for removing persistent organic pollutants from water.
• To immobilize laccase onto amino-functionalized magnetic biochar for enhanced stability and reusability.
• To investigate the degradation mechanism and efficiency of the biocatalyst against bisphenol A and other POPs.

Main Methods:

• Biomass-derived biochar was functionalized with amino groups and magnetic nanoparticles.
• Laccase was immobilized onto the functionalized biochar using electrostatic adsorption, precipitation, and cross-linking.
• The immobilized enzyme aggregates were characterized for stability (pH, thermal, storage).
• Degradation of bisphenol A and other POPs was evaluated, and the removal efficiency over multiple cycles was assessed.

Main Results:

• The immobilized enzyme aggregates demonstrated superior pH tolerance, thermal stability, and storage stability compared to free laccase.
• Complete removal of 20 mg/L bisphenol A was achieved within 60 minutes through C-C bond cleavage and hydroxylation.
• The biocatalyst maintained approximately 90% removal efficiency after six cycles of reuse.
• The biocatalyst effectively removed various other persistent organic pollutants and showed applicability in real environmental water samples.

Conclusions:

• Stabilized enzyme aggregates on amino-functionalized magnetic biochar represent a highly efficient and recyclable biocatalyst.
• This approach offers a sustainable and effective method for water purification and the recovery of biomass resources.
• The developed biocatalyst shows substantial potential for addressing water contamination by persistent organic pollutants.