Antibacterial and antibiofilm activities of curcumin-mediated green-synthesised silver nanoparticles against Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa

The rise in nosocomial infections caused by multidrug-resistant bacteria and the ability of bacteria to form biofilms have necessitated the exploration of alternative antimicrobial strategies. In this study, silver nanoparticles (AgNPs) were synthesised using a green method in the presence of curcumin to suppress the biofilm-forming abilities of Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Curcumin was utilized in a green synthesis approach to facilitate reduction and create stable AgNPs. The resulting curcumin-capped AgNPs (Cur-AgNPs) were tested for their antibacterial and antibiofilm properties using microbroth dilution and microtiter plate methods (MTP). The MTT assay was carried out to evaluate the potential toxicity of Cur-AgNPs. Cur-AgNPs exhibited a minimum inhibitory concentration (MIC) of 14.12 µg/mL against both P. aeruginosa and MRSA. Furthermore, Cur-AgNPs demonstrated antibiofilm activity by suppressing biofilm formation and disrupting existing biofilms, and were non-toxic to the murine fibroblast cell line (L929) at the MIC concentration, as determined by the MTT assay. Cur-AgNPs demonstrated significant antibacterial and antibiofilm activity against both Gram-positive and Gram-negative bacterial strains. These results suggest that green-synthesised AgNPs represent a promising approach for biofilm management. Furthermore, this study highlights the potential of curcumin as a capping agent to substantially improve the antibacterial and antibiofilm properties of AgNPs.