Green-Synthesized Silver Nanoparticles from Acalypha godseffiana and Their Biofilm-Disruptive Activity against ESKAPE Pathogens

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The emergence of multidrug-resistant (MDR) pathogens, including the ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli), underscores the urgent need for novel antimicrobial agents. This study reports the green synthesis of silver nanoparticles (AgNPs) using Acalypha godseffiana leaf extract and evaluates their potent antibiofilm activity against these critical pathogens. UV–Vis spectroscopy confirmed nanoparticle formation through a characteristic surface plasmon resonance peak at 437 nm. In comparison, transmission electron microscopy (TEM) revealed spherical nanoparticles ranging from 1 to 20 nm, stabilized by plant-derived phytochemicals. Energy-dispersive X-ray (EDX) analysis verified the presence of elemental silver with a peak at 3.0 keV, accompanied by organic capping agents. The biosynthesized AgNPs demonstrated dose-dependent inhibition of biofilm formation, exhibiting maximal activity against S. aureus (61.71% inhibition at 100 μg/mL) and A. baumannii (52.58%). Minimum biofilm eradication concentrations (MBEC) indicated complete disruption of established biofilms at 200 μg/mL for P. aeruginosa and 400 μg/mL for E. faecium. Mechanistic investigations suggest that the antibiofilm effects are mediated by reactive oxygen species (ROS) generation, degradation of extracellular polymeric substances (EPS), and disruption of bacterial membranes, potentiated by synergistic interactions with flavonoids and phenolic compounds from the plant extract. These findings highlight A. godseffiana-derived AgNPs as a sustainable and eco-friendly alternative to conventional antibiotics, particularly for managing biofilm-associated MDR infections. The study provides critical insights and dosage thresholds essential for future translational applications, including medical device coatings and topical antimicrobial formulations.