Background: Facile, environmental friendly synthesis of metal oxide nanoparticles is of
paramount importance when its biological applications are considered.
Objective: Current study reports phyto-fabrication of Zinc oxide nanoparticles using aqueous extract
of Piper betel leaves as stabilizing and capping agent using co-precipitation method.
Results: P betel synthesized ZnO nanoparticles (PZnO) was characterized using Powder X-ray diffraction,
UV-Visible spectroscopy, scanning electron microscopy and dynamic light scattering. PXRD
pattern demonstrated hexagonal wurtzite structure with preferred orientation (100) plane confirmed by
JCPDS file 36-1451. UV- Vis spectroscopy showed peak at 370 nm due to band edge of semiconductor,
the PZnO. The average particle size determined by DLS measurement was 69 nm and morphologically
the particles were short rod shaped and agglomerated as demonstrated by SEM images. Antibacterial
activity of PZnO against dental pathogens namely Streptococcus mutans and Lactobacillus
acidphillus was performed using well-diffusion method and antioxidant activity against 2, 2 diphenyl
1 picrylhydrazyl (DPPH) free radicals and were compared with ZnO used in clinical dentistry
(DZnO). PZnO showed higher antioxidant activity of ~70% at 200 µg/mL with consistent activity at
lower aliquots. PZnO showed higher antimicrobial activity than DZnO against both tested microbes
and also exhibited inhibitory effects in concentration as low as 3.25 µg/mL. Cytotoxicity study using
Balb 3T3 mouse fibroblast cell lines showed <40% cellular growth inhibition by both PZnO and
DZnO, indicating their benignity towards selected cell lines.
Conclusion: Phyto-fabricated facile PZnO nanoparticles having demonstrable antibacterial and antioxidant
activity can be considered for use in clinical dentistry after further clinical trials.