Carbonic anhydrase encapsulation using bamboo cellulose scaffolds for efficient CO₂ capture and conversion

Area of Science:

• Biocatalysis
• Biomaterials
• Environmental Science

Background:

• Carbonic anhydrase (CA) is crucial for CO2 hydration, a key process in carbon capture and utilization.
• Enzyme immobilization is vital for enhancing CA stability and reusability in industrial settings.
• Developing sustainable and cost-effective immobilization strategies is essential for practical applications.

Purpose of the Study:

• To immobilize carbonic anhydrase (CA) onto a renewable bamboo cellulose scaffold.
• To evaluate the enhanced catalytic performance, stability, and reusability of the immobilized CA.
• To assess the impact of immobilized CA on microalgae biomass production and biomolecule synthesis.

Main Methods:

• Delignified bamboo cellulose was functionalized via oxidation-induced cellulose aldehydation.
• Carbonic anhydrase (CA) was immobilized using Schiff base linkage onto the modified cellulose scaffold.
• Catalytic activity was assessed using p-NPA hydrolysis and CO2 hydration models.
• Stability and reusability were tested under thermal and pH variations, and in microalgae cultures.

Main Results:

• Immobilized CA exhibited increased optimal temperature (approx. 45°C) and pH (approx. 9.0) compared to free CA.
• CA activity retention exceeded 60%, with larger scaffold sizes showing improved performance.
• Immobilized CA maintained over 80% activity after 5 cycles and demonstrated high stability under harsh conditions.
• Microalgae biomass production increased by ~16% with enhanced biomolecule synthesis using immobilized CA.

Conclusions:

• Facile and green immobilization of CA onto bamboo cellulose enhances enzyme stability, reusability, and catalytic efficiency.
• The developed immobilized CA shows significant potential for CO2 conversion and utilization technologies.
• Bamboo cellulose serves as a promising sustainable scaffold for enzyme immobilization in biotechnological applications.