Bio-based and cost effective method for phenolic compounds removal using cross-linked enzyme aggregates

Area of Science:

• Environmental Biotechnology
• Enzyme Immobilization
• Wastewater Treatment

Background:

• Wastewater contamination by phenolic compounds poses environmental risks.
• Developing stable and reusable enzymatic catalysts is crucial for effective bioremediation.
• Raphanus sativus var. niger (RSVNP) peroxidase offers a potential new source for enzyme-based treatment.

Purpose of the Study:

• To develop a green and efficient method for wastewater treatment using immobilized RSVNP.
• To enhance the stability and reusability of RSVNP through cross-linked enzyme aggregates (CLEAs).
• To evaluate the efficacy of RSVNP-CLEAs in degrading phenol and p-cresol.

Main Methods:

• Immobilization of RSVNP as cross-linked enzyme aggregates (CLEAs) using acetone and glutaraldehyde.
• Characterization of RSVNP-CLEAs for chemical, thermal, and storage stability.
• Assessing the degradation efficiency of phenol and p-cresol under various operating conditions.
• Evaluating the reusability of RSVNP-CLEAs over multiple treatment cycles.

Main Results:

• RSVNP-CLEAs achieved high aggregation yield (85%) and recovered activity (>29%).
• Immobilized enzyme exhibited superior chemical, thermal, and storage stability compared to free RSVNP.
• RSVNP-CLEAs demonstrated high degradation efficiencies: 98% for p-cresol in 40 min and 92% for phenol in 1 hour.
• The enzyme retained significant activity after multiple reuses, degrading 71% phenol and 54% p-cresol by the third and fourth batches, respectively.

Conclusions:

• Immobilization of RSVNP as CLEAs provides a robust and stable enzymatic system for wastewater treatment.
• RSVNP-CLEAs are effective in removing phenolic pollutants like phenol and p-cresol with high efficiency.
• The reusability of RSVNP-CLEAs supports their potential for cost-effective and sustainable environmental applications.