A hydrogel-based composite facilitates efficient and recyclable tetracycline biodegradation in aquatic environments

Area of Science:

• Environmental Science
• Biotechnology
• Materials Science

Background:

• Tetracycline antibiotic residues pose risks through cytotoxicity and promoting antibiotic resistance.
• The Tet(X4) enzyme efficiently inactivates tetracyclines but faces stability and cost challenges.
• Developing stable and economical methods for tetracycline residue removal is crucial for environmental and public health.

Purpose of the Study:

• To create a hydrogel-based composite for stable and cost-effective encapsulation of the Tet(X4) enzyme.
• To enhance the efficiency and recyclability of Tet(X4) for eliminating tetracycline residues in aqueous environments.
• To evaluate the safety and applicability of the developed composite for real-world environmental remediation.

Main Methods:

• Synthesized a composite material using carboxymethyl chitosan (CC), agarose (Ag), Tet(X4) enzyme, Fe3O4, and CaO2.
• Assessed the enzymatic activity, stability (UV, ionic strength), and degradation efficiency of the composite.
• Investigated the magnetic recyclability of the composite and performed safety assessments in mouse models.

Main Results:

• The composite maintained significant Tet(X4) enzymatic activity (73.1% ± 9.4%) with good stability.
• A 1.0 g composite with 3% Tet(X4) efficiently degraded tetracycline residues, achieving ~85% removal in various water types.
• The magnetic properties enabled multiple uses, significantly reducing costs, and mouse experiments confirmed the composite's safety.

Conclusions:

• The hydrogel-based composite provides a stable, recyclable, and cost-effective platform for Tet(X4)-mediated tetracycline removal.
• Encapsulation of enzymes in nanocarriers is a viable strategy for enhancing antibiotic residue degradation.
• This approach offers a promising solution for environmental remediation of tetracycline contamination and mitigating antibiotic resistance.