Enzyme-Functionalized Cellulose Beads as a Promising Antimicrobial Material

Abstract

The extensive use of antibiotics over the last decades is responsible for the emergence of multidrug-resistant (MDR) microorganisms that are challenging health care systems worldwide. The use of alternative antimicrobial materials could mitigate the selection of new MDR strains by reducing antibiotic overuse. This paper describes the design of enzyme-based antimicrobial cellulose beads containing a covalently coupled glucose oxidase from Aspergillus niger (GOx) able to release antimicrobial concentrations of hydrogen peroxide (H 2 O 2 ) (≈ 1.8 mM). The material preparation was optimized to obtain the best performance in terms of mechanical resistance, shelf life, and H 2 O 2 production. As a proof of concept, agar inhibition halo assays (Kirby-Bauer test) against model pathogens were performed. The two most relevant factors affecting the bead functionalization process were the degree of oxidation and the pH used for the enzyme binding process. Slightly acidic conditions during the functionalization process (pH 6) showed the best results for the GOx/cellulose system. The functionalized beads inhibited the growth of all the microorganisms assayed, confirming the release of sufficient antimicrobial levels of H 2 O 2 . The maximum inhibition efficiency was exhibited toward Pseudomonas aeruginosa ( P. aeruginosa ) and Escherichia coli ( E. coli ), although significant inhibitory effects toward methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus were also observed. These enzyme-functionalized cellulose beads represent an inexpensive, sustainable, and biocompatible antimicrobial material with potential use in many applications, including the manufacturing of biomedical products and additives for food preservation.

Tannic Acid‐Promoted Deposition of Glucose Oxidase on Titanium Surfaces for Mitigation of Persistent Bacterial Infections

“…Due to the enzymatic production of powerful disinfectant (H 2 O 2 ), GOD can be seen as an indirect antibacterial agent. [ 23 ] The antibacterial effects of the GOD in the presence and absence of glucose were studied by determining the corresponding minimum inhibitory concentration (MIC) values through the two‐fold dilution method (Figure S6, Supporting Information). In the absence of glucose, the MIC values of GOD against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) are 2.5 and 0.625 U mL −1 , respectively.…”

Combination of Enzymes with Materials to Give Them Antimicrobial Features: Modern Trends and Perspectives

“…The analysis of current trends in the functionalization of various materials due to the introduction of different enzymes in them ( Table 1 [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ], Figure 1 ) allows us to make several generalizations at the initial stage at once. First of all, this concerns the enzymes used.…”

“…First of all, this concerns the enzymes used. Their diversity is not too wide; mainly these are enzymes that belong to the class of oxidoreductases [ 16 , 17 , 18 , 19 , 20 , 28 , 35 , 36 ] and hydrolases [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 37 , 38 , 39 , 40 , 41 ]. Peptidases [ 21 , 31 , 34 , 38 ], various carbohydrases [ 22 , 23 , 24 , 25 , 26 , 27 , 29 , 30 , 32 , 33 , 34 , 39 , 40 ], and esterases [ 37 , 41 ] are actively used among hydrolases for obtaining materials with antimicrobial properties ( Figure 1 ).…”

“…The main action of the used enzymes is aimed at inhibiting cell growth, assembling their structural elements, primarily the cell wall, as well as neutralizing the actions of the Quorum Sensing (QS)-signaling molecules of cells, which mainly transfer bacteria to the status of high resistance to the effects of antimicrobial agents [ 16 , 17 , 18 , 19 , 20 , 24 , 25 , 26 , 30 , 37 , 41 ].…”

“…It is interesting to note that among the targets for the effects of materials functionalized by enzymes, there are both Gram-positive [ 16 , 17 , 18 , 20 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 34 , 35 , 37 , 39 , 40 , 41 ] and Gram-negative [ 16 , 17 , 18 , 19 , 21 , 22 , 23 , 24 , 26 , 31 , 32 , 33 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ] bacteria, as well as yeast cells mainly of the genus Candida [ 26 , 28 ].…”