Enzyme-Functionalized Cellulose Beads as a Promising Antimicrobial Material

Area of Science:

• Biomaterials Science
• Antimicrobial Materials
• Enzyme Immobilization

Background:

• Rising threat of multidrug-resistant (MDR) microorganisms due to extensive antibiotic use.
• Need for alternative antimicrobial strategies to reduce antibiotic overuse and mitigate MDR strain selection.
• Cellulose as a sustainable and biocompatible material for biomedical applications.

Purpose of the Study:

• To design and optimize enzyme-based antimicrobial cellulose beads.
• To covalently couple glucose oxidase (GOx) from Aspergillus niger to cellulose beads.
• To evaluate the antimicrobial efficacy of the developed beads against model pathogens.

Main Methods:

• Optimization of material preparation for mechanical resistance, shelf life, and hydrogen peroxide (H2O2) production.
• Functionalization of cellulose beads with GOx, investigating the impact of oxidation degree and pH.
• Antimicrobial activity assessment using agar inhibition halo assays (Kirby-Bauer test) against P. aeruginosa, E. coli, MRSA, and S. aureus.

Main Results:

• Optimized cellulose beads demonstrated efficient H2O2 release (≈ 1.8 mM) with good mechanical properties and shelf life.
• Slightly acidic conditions (pH 6) during functionalization yielded the best GOx/cellulose system performance.
• The functionalized beads effectively inhibited the growth of all tested microorganisms, with maximum efficacy against P. aeruginosa and E. coli.

Conclusions:

• Enzyme-functionalized cellulose beads are a viable, inexpensive, and sustainable antimicrobial material.
• The developed beads release sufficient H2O2 to exert broad-spectrum antimicrobial activity.
• Potential applications include biomedical products and food preservation, offering an alternative to conventional antibiotics.