Stability, Toxicity, and Antibacterial Potential of Gallic Acid-Loaded Graphene Oxide (GAGO) Against Methicillin-Resistant Staphylococcus aureus (MRSA) Strains

Abstract

Background The impetuous usage of antibiotics has led to the perpetual rise of methicillin-resistant Staphylococcus aureus (MRSA), which has garnered the interest of potential drug alternatives, including nanomaterials. Purpose The present study investigates the stability, toxicity, and antibacterial potential of gallic acid-loaded graphene oxide (GAGO) on several MRSA strains. Methods The stability of a synthesized and characterized GAGO was monitored in different physiological media. The toxicity profile of GAGO was evaluated in 3T3 murine fibroblast cells and the embryonic zebrafish model. The antibacterial activity of GAGO against MRSA, methicillin-susceptible S. aureus (MSSA), and community-acquired MRSA; with or without Panton-valentine leucocidin gene (MRSA- pvl + and MRSA- pvl- ) was investigated through disk diffusion, CFU counting method, time-kill experiment, and high-resolution transmission electron microscopy (HRTEM) observation. Results A stable GAGO nanocomposite has shown an improved toxicity profile in 3T3 murine fibroblast cells and zebrafish embryos, besides exhibiting normal ROS levels than graphene oxide (GO) and GA (gallic acid). The nanocomposite inhibited the growth of all bacterial strains employed. The effectiveness of the GAGO nanocomposite was comparable to cefoxitin (CFX), at ≥150 µg/mL in MRSA and MSSA. GAGO exhibited a significantly delayed response towards MRSA- pvl + and MRSA- pvl- , with increased inhibition following 8 to 24 h of exposure, while comparable activity to native GA was only achieved at 24 h. Meanwhile, for MRSA and MSSA, GAGO had a comparable activity with native GA and GO as early as 2 h of exposure. HRTEM observation further reveals that GAGO-exposed cells were membrane compromised. Conclusion In summary, the present study indicates the antibacterial potential of GAGO against MRSA strains, but further study is warranted to understand the mechanism of action of GAGO and its resistance in MRSA strains.

A Cysteine-Maleimide-Based Design for Hemostatic, Antibacterial, and Biodegradable Wound Dressing

“…We determined the antibacterial activity against Gram-negative E. coli (ATCC 25922) and Gram-positive S.aureus (ATCC 25923, generously supplied by Professor Weihui Wu from the College of Life Sciences, Nankai University) by the Kirby Bauer disk diffusion method. Evenly distributed the bacterial suspension onto LB agar plates, followed by the placement of sterile 6 mm antibiotic disks soaked in 5 mg/mL, 10 mg/mL, 20 mg/mL, 30 mg/mL, 40 mg/mL, and 50 mg/mL MCTH on the plates, incubated at 37 °C for 24 h, and then measured the diameter of the inhibition zones …”

“…Evenly distributed the bacterial suspension onto LB agar plates, followed by the placement of sterile 6 mm antibiotic disks soaked in 5 mg/mL, 10 mg/mL, 20 mg/mL, 30 mg/mL, 40 mg/mL, and 50 mg/mL MCTH on the plates, incubated at 37 °C for 24 h, and then measured the diameter of the inhibition zones. 58 Cell Culture. L929 mouse fibroblast cells were cultured in DMEM (Gibco) supplemented with 1% penicillin and streptomycin (Gibco) and 10% fetal bovine serum (Gibco).…”

An update on the potential mechanism of gallic acid as an antibacterial and anticancer agent

“…They reported that its efficacy on bacteria at concentrations of ≥150 μg/mL is comparable to cefoxitin. Moreover, this nanoformulation increased the biocompatibility of GA in physiological environments and GAGO had little toxicity in 3T3 murine fibroblast cells and zebrafish embryos cells at all investigated times (24, 48, 72 h) compared to GA alone (Shamsi et al, 2022). Another group of researchers designed liposomes loaded with GA (GA-LIP) and GA-LIP decorated with Lactoferrin (LF-GA-LIP).…”

“…The results showed the preparation of this nanoformulation significantly increased the antibacterial efficacy of GA against MRSA compared to GA alone. It is suggested that this compound can be a suitable antibacterial agent against multi‐drug‐resistant bacteria (Shamsi et al, 2022 ). Another study showed that the effectiveness of GAGO against MSSA and MRSA was comparable to the first 2 hours of exposure of bacteria to GA and GO alone.…”

Photodynamic Antibacterial Therapy of Gallic Acid-Derived Carbon-Based Nanoparticles (GACNPs): Synthesis, Characterization, and Hydrogel Formulation

“…Gallic acid was altered because CNPs can increase antibacterial activity, which is consistent with the findings of previous studies [ 32 ]. Moreover, because of their low toxicity, the previous research utilized gallic acid-loaded graphene oxide against methicillin-resistant Staphylococcus aureus (MRSA) strains, which showed low toxicity of nanocomposites at more than 500 μg/mL for up to 72 h in zebrafish embryos [ 33 ].…”