Enhanced antimicrobial, antibiofilm and anticancer activities of biocompatible neem gum coated palladium nanoparticles

Abstract

The present study highlights a quick and cost effective, fabrication of biocompatible and water dispersible neem gum coated palladium nanoparticles (NG@Pd NPs) and assessment of their pharmacological applications. Palladium nanoparticles were synthesized through a biogenic route using the aqueous leaf extract of Orthosiphon stamineus. The fabricated nanocomposite was characterized by spectroscopic and microscopic analyses. The results of antimicrobial studies revealed that the NG@Pd NPs exhibited enhanced antibacterial activity against E. coli, S. aureus and Extended spectrum beta lactamase (ESBL) strain when compared to the Pd NPs alone. Antibiofilm studies illustrated a concentration dependent inhibition of biofilm formation in MSSA strain with the IC 50 value of 15.25 ± 0.012 μg/mL, while the Pd NPs showed lower inhibitory effect. Anticancer potential illustrated that the NG@Pd NPs showed potent antiproliferative effect against A549 cells in proportion to the concentration with 50 % inhibition at 45.6 ± 0.25 μg/mL. NG@Pd NPs exhibited enhanced reactive oxygen species leading to DNA fragmentation, disruption of mitochondrial membrane potential inducing apoptosis through the activation of caspase 3/9. Safety evaluation studies revealed that the NG@Pd NPs exhibited neither cytotoxicity nor hemolysis illustrating the biocompatible nature of NG@Pd NPs. Overall, the present work manifests the possibility of developing NG@Pd NPs as a suitable candidate for antimicrobial and lung cancer therapy.