Antioxidant, antibacterial, and wound-healing activities of Aframomum corrorima seed extracts and their biosynthesized silver nanoparticles

The rising prevalence of antibiotic-resistant bacterial infections has intensified the search for alternative antibacterial and wound-healing agents. This study evaluated the antioxidant, antibacterial, and wound-healing activities of Aframomum corrorima seed extracts and silver nanoparticles (AgNPs) biosynthesized using the aqueous seed extract. Qualitative phytochemical screening revealed solvent-dependent profiles of flavonoids, phenolics, tannins, glycosides, quinones, and saponins. Optimized synthesis conditions (pH 11, 5 mM AgNO₃, 65 °C, and 60 min) yielded a characteristic surface plasmon resonance band at 400–450 nm. Structural and morphological characterization indicated a face-centered cubic silver structure, a Scherrer crystallite size of 14.9 nm, and predominantly spherical particles with dry-state agglomeration as confirmed by X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. Fourier-transform infrared spectroscopy (FTIR) suggested the involvement of extract-derived hydroxyl- and carbonyl-containing compounds in nanoparticle capping. In the DPPH assay, the methanol and ethanol extracts exhibited radical-scavenging activities of 90.0% (IC₅₀: 21.37 ± 0.86 mg/mL) and 87.7% (IC₅₀: 54.48 ± 0.72 mg/mL) at 250 mg/mL, respectively, whereas biosynthesized AgNPs showed 74.0% inhibition at 10 mg/mL. Against reference strains of Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa , the methanol extract at 500 mg/mL produced inhibition zones of 29 ± 0.34, 28 ± 0.54, and 25 ± 0.46 mm, respectively, compared with 26 ± 0.71, 23 ± 0.51, and 18 ± 0.67 mm for AgNPs at 10 mg/mL. Extract–AgNP combinations were active against all three strains but did not consistently produce larger inhibition zones than the individual components; synergy was not showed. Acute toxicity assessments recorded no mortality or overt clinical signs during 14-day observation following a single oral dose of 2 g/kg or a single dermal application, indicating tolerability under the tested conditions. For in vivo wound-healing analyses, 32 of 50 mice with bacterially inoculated full-thickness excision wounds were evaluated post-attrition. Linear mixed-effects models identified significant treatment × day interactions in the E. coli and S. aureus models (p = 0.038 and p = 0.005, respectively). The combined ointment significantly increased wound contraction relative to the vehicle in S. aureus -inoculated wounds by 14.0 %age points across days 2–18 (Holm-adjusted p = 0.014). In the E. coli model, four of five formulation-treated wounds closed by day 14, though differences from controls were not statistically significant after adjustment, and no formulation outperformed the reference drug nitrofurazone in either model. These findings demonstrate the in vitro antioxidant and antibacterial properties of A. corrorima extracts and synthesized AgNPs, supporting further exploration of these topical formulations, although they did not establish superior synergistic effects over individual components or nitrofurazone.