Eco-friendly synthesis of silver nanoparticles using Coffea arabica husk for enhanced antibacterial and anti-cancer applications

Silver nanoparticles (AgNPs) are widely recognized for their diverse applications in medicine, electronics and environmental remediation. This research introduces a novel green synthesis technique for AgNPs using C . arabica husk extract as a natural reducing and stabilizing agent. Unlike other agro-wastes, C . arabica husk is uniquely rich in bioactive compounds such as amino acids, alkaloids and organic acids, which were identified using liquid chromatography-mass spectrometry. The synthesized AgNPs were characterized using UV-Vis spectrophotometry, scanning electron microscopy and particle size analysis, which confirmed the formation of spherical nanoparticles with an average size of 147 nm. Zeta potential measurements (-27.8 mV) indicated strong nanoparticle stability, and Fourier transform infrared spectroscopy identified functional groups (O-H and C-N) responsible for stabilization. X-ray diffraction analysis confirmed a crystalline structure consistent with a face-centered cubic arrangement. Antimicrobial assays showed inhibition zones of 8.2, 5.3, 4.0 and 3.8 mm for Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli and Staphylococcus aureus, respectively. Cytotoxicity testing on MCF-7 breast cancer cells demonstrated an IC50 value of 16.7 mu g/mL, with over 80 % cell viability in L6 normal skeletal muscle cells, highlighting selective toxicity. This study fills the gap in using C . arabica husk for AgNP synthesis, demonstrating its unique bioactive composition and dual functionality for both nanoparticle synthesis and biomedical applications.