Comparative in Vitro Antibacterial Efficacy of Peperomia Pellucida Nanoemulsion, Gentamicin, and Silver Sulfadiazine Against Common Burn Wound Pathogens

Background: Burn wound infections remain a major cause of morbidity and mortality, predominantly caused by multidrug-resistant pathogens such as Pseudomonas aeruginosa, Acinetobacter baumannii, and methicillin-resistant Staphylococcus aureus (MRSA). Topical agents like silver sulfadiazine (SSD) and gentamicin are standard, but resistance and toxicity drive interest in natural alternatives. This study compared the in vitro antibacterial activity of Peperomia pellucida nanoemulsion (PPNE), gentamicin, and SSD against these pathogens.

Methods: An experimental post-test only control group design was employed. Clinical isolates or reference strains of A. baumannii, MRSA, and P. aeruginosa were cultured on Mueller-Hinton agar. Antibacterial activity was assessed using the Kirby-Bauer disk diffusion method with disks impregnated with PPNE (5%), gentamicin topical preparation, or SSD. Zone of inhibition (ZOI) diameters were measured after 18–24 h incubation at 37°C (three replicates per group). Data were analyzed using Kruskal-Wallis test (p < 0.05 significant).

Results: PPNE produced the largest mean ZOI against A. baumannii (25.9 mm; strong activity), significantly outperforming gentamicin (17.0 mm) and SSD (11.3 mm) (p = 0.005). Against MRSA, ZOIs were comparable (PPNE 11.8 mm, gentamicin 11.3 mm, SSD 11.1 mm; all moderate; p = 0.005). For P. aeruginosa, PPNE (10.7 mm) and SSD (10.5 mm) showed moderate activity, superior to gentamicin (9.5 mm; weak-moderate; p = 0.005).

Conclusion: PPNE demonstrated superior or comparable in vitro antibacterial efficacy compared to conventional agents, particularly against A. baumannii. These findings support further in vivo and clinical evaluation of PPNE as a potential adjunct or alternative in burn wound infection management.