Kappaphycus Alvarezii -Mediated Cu Nanoparticles: Unveiling Antimicrobial Potential against E.coli through Membrane Permeability, Depolarization, and Peroxidation Detection

The study investigates the synthesis of copper nanoparticles mediated by the red seaweed Kappaphycus alvarezii and their antimicrobial efficacy against E.coli. The synthesis process, confirmed through UV-Vis spectrophotometry, exhibited a peak at 232.70 nm, indicating the formation of Cu NPs. FTIR spectroscopy revealed various functional groups on the nanoparticle surface, including alkyne, alkane, alkene, sulfate, vinyl ether, amine, and halo compounds. X-ray Diffraction analysis identified an FCC structure with an average crystallite size of 42.6 nm. The impact of Cu NPs on E.coli was assessed through membrane permeability, membrane depolarization, and lipid peroxidation assays. Results demonstrated a concentration-dependent increase in membrane permeability and depolarization, indicating significant disruption of the bacterial cell membrane. Lipid peroxidation assays revealed escalating oxidative damage to lipids with higher Cu NP concentrations, confirming the potent antimicrobial action of the nanoparticles. This study highlights the potential of green synthesis of Cu NPs using Kappaphycus alvarezii as a sustainable and effective approach for developing novel antimicrobial agents.