Antibacterial and Antibiofilm Efficacy of Green Synthesised Haloxylon Capped Silver Nanoparticles Against Enterococcus faecalis

This study synthesised and characterised Haloxylon-capped silver nanoparticles (Haloxylon-AgNPs) and assessed their antibacterial and antibiofilm activity against Enterococcus faecalis. The study also examined Haloxylon-AgNPs' ability to target E. faecalis biofilms in root canals. Haloxylon salicornicum extract was used to synthesise silver nanoparticles. Physiochemical characterisation of Haloxylon-AgNPs was conducted. Antimicrobial and antibiofilm activity of Haloxylon-AgNPs was studied by agar diffusion method, minimum inhibitory concentration (MIC) determination, time-kill assay, confocal laser scanning microscopy (CLSM) and qPCR for virulence gene attenuation. One hundred and twenty extracted teeth were infected with E. faecalis and treated with either Haloxylon-AgNPs, chlorhexidine, calcium hydroxide or saline. The data were analysed using a one-way ANOVA and Tukey multiple comparison test to investigate the bacterial reduction between groups (p < 0.05, significant; p < 0.001, highly significant). A significant reduction in the thickness of biofilm and expression of cylA virulence gene of Haloxylon-AgNPs treated E. faecalis was observed. No difference was observed between Haloxylon-AgNPs, chlorhexidine and calcium hydroxide in the tooth model.