Work

Potent antimicrobial and anti-biofilm effects of Uvaria chamae on Staphylococcus aureus strains via potential cell wall interference and lack of resistance induction

Year: 2025

Type: article

Abstract: ETHNOPHARMACOLOGICAL RELEVANCE: Antimicrobial resistance (AMR) is a critical global health issue, particularly in sub-Saharan Africa. Traditional remedies, such as Uvaria chamae, are commonly used in West Africa to treat bacterial infections. AIM OF THE STUDY: To comprehensively evaluate the antimicrobial, anti-biofilm, and resistance induction profiles of U. chamae. MATERIALS AND METHODS: Ethanolic, hydroethanolic, and aqueous root and leaves extracts were assayed against Gram-positive and -negative bacteria. Biofilm inhibition, time-kill kinetics, and bacterial morphology were studied. In vivo efficacy was assessed using a Caenorhabditis elegans infection model. Chemical profiling was conducted via UPLC-PDA-QTOF/MS, and cytotoxicity evaluated in A549 and THP-1 cells. RESULTS: The ethanolic extract of the roots was the most potent, showing selective activity against S. aureus and MRSA (MIC = 4 μg/mL, MBC = 8 μg/mL). Time-kill assays confirmed bacteriostatic activity at MIC and bactericidal effects at higher concentrations. The extract effectively disrupted biofilms and did not induce resistance, unlike ciprofloxacin. It did not damage bacterial membranes but altered cell wall morphology. Low cytotoxicity was observed in human cells, and no toxicity was detected in C. elegans. In vivo, the extract significantly reduced bacterial burden in infected nematodes at 14 and 32 μg/mL. LC-MS analysis on active fractions revealed several known antimicrobial compounds, aligning with previously reported metabolite profile of U. chamae roots. CONCLUSION: U. chamae root extract exhibits strong, selective antibacterial activity with low toxicity, no resistance induction, and in vivo efficacy. These findings support its potential as a locally relevant option to combat AMR in Africa.

Source: Journal of Ethnopharmacology

DOI: 10.1016/j.jep.2025.120434