Antibacterial Activity of Mouthwash Incorporated with Silica Nanoparticles against S. aureus, S. mutans, E. faecalis: An in-vitro Study

Silica based nanoparticles are used in various fields of medical sciences to diagnose, control disease, for genetic disorders, owing to their size, surface area, biocompatibility and low toxicity. In dentistry, silica nanoparticles have been used as dental filler, teeth whitening agent but limited evidence is there regarding antimicrobial activity against oral pathogens. Therefore, the current study was conducted to assess the anti-bacterial activity of mouthwash incorporated with silica nanoparticles against oral pathogens. Tetraethoxysilane, ammonium hydroxide, absolute ethanol were used and centrifuged to obtain the silica nanoparticle pellet. XRD analysis was done to confirm the characterization of the thus obtained silica nanoparticle. The mouthwash was prepared with the synthesized silica nanoparticle as the main constituent. Agar well diffusion method was used to assess the antimicrobial activity against S. mutans, S. aureus and E. faecalis. The XRD analysis confirmed the amorphous nature of the synthesized silica nanoparticles.The zone of inhibition was found to increase as the concentrations increased mainly for S. aureus and E. faecalis. The synthesized nanoparticles incorporated mouthwash showed good potential as antimicrobial agents against strains of gram positive bacteria. Further animal studies/in vivo research should be conducted to validate the above findings

Cassia oleoresin Mediated Synthesis of Magnesium Oxide Nanoparticles and Brine Shrimp Lethality Assay

Cassia oleoresin is an extract isolated from dried barks of Cinnamomum cassia Blume (family Lauracea). The plant has been reported to have anti-diabetic, anti-oxidant, anti-hypertriglyceridemic effect, mainly due to its phytochemical constituents such as phenolic and volatile compounds. Cinnamon also helps in arthritis, fibromyalgia and psoriasis. The aim of this study was to prepare magnesium oxide nanoparticles using Cassia oleoresin and to evaluate the cytotoxic effect on Brine shrimp. The magnesium oxide nanoparticle was prepared from magnesium chloride and Cassia oleoresin and was confirmed by UV- Visible Spectroscopy and morphology was confirmed by TEM. Brine shrimps lethality bioassay was carried out to investigate the cytotoxicity of Cassia oleoresin mediated magnesium oxide nanoparticles. Ten brine shrimp nauplii were placed in each well of the Eliza plate and filled with 5 μL ,10 μL ,15 μL ,20 μL ,25 μL of Cassia oleoresin mediated magnesium oxide nanoparticles After 24 hours of incubation, the wells were observed and the number of surviving brine shrimp nauplii were counted to assess the cytotoxicity. The UV -Visible spectroscopy showed a peak at 400 peak and TEM analysis showed a particle size of 70 nm. After 24 hours incubation of the brine shrimps in the nanoparticle solution, all 10 brine shrimps survived in 5μL and 10 μL concentrations. 3 brine shrimps nauplii survived in 15μL conc. 1 brine shrimp nauplii survived in 20μL and 25μL concentrations each. Within the limits of this study it can be concluded that at low concentrations the prepared nanoparticle was safe and may be used for biomedical application.

Assessment of Antimicrobial Efficacy of Zinc Oxide Nanoparticles Synthesized Using Clove and Cinnamon Formulation against Oral Pathogens - An In Vitro Study.

Zinc Oxide nanoparticle is of particular interest among researchers due to its wide range of applications. Green synthesis of nanoparticles has many benefits like being eco-friendly, less time consuming, cost effective, stable operation, and more importantly the process can be carried out without the involvement of any hazardous chemicals. Clove and cinnamon are known to have antimicrobial activity. Hence, this study was conducted to assess the antimicrobial efficacy of zinc oxide nanoparticles reinforced with clove and cinnamon against oral pathogens. METHODSThis is an in vitro study. The organisms used were Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis. These bacteria were inoculated in their respective medium and incubated overnight. Agar well diffusion method was used to assess the antimicrobial efficacy of the nanoparticles at 25 µL, 50 µL and 100 µL. RESULTSZone of inhibition was found to be highest at 100 µL against Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis (15 mm, 13 mm, and 13 mm respectively). CONCLUSIONSFindings from this study suggest that zinc oxide nanoparticles reinforced with clove and cinnamon extracts has the potential as an antimicrobial agent against Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis and can be used as an alternative to commercially available antimicrobial agents.