Nagarajan Keerthiga

Bio: Nagarajan Keerthiga is an academic researcher. The author has contributed to research in topics: Silver nanoparticle. The author has an hindex of 1, co-authored 1 publications receiving 14 citations.

Antibacterial and Antioxidant Potential of Silver Nanoparticles Biosynthesized Using the Spruce Bark Extract

Abstract: Biosynthesized silver nanoparticles (AgNPs) are widely used in Pharmacy and Medicine. In particular, AgNPs synthesized and mediated by plant extracts have shown topossess several biological activities. In the present study, AgNPs were synthesized using Picea abies L. stem bark extract as reducing agent. Factors, such as metal ion solution, pH, and time, which play a role in the AgNPs synthesis, were assessed. The synthesized AgNPs were characterized by Ultraviolet-Visible Spectrometry, Fourier transform infrared spectroscopy, and Transmission Electron Microscopy (TEM). Further, the study has been extended to evaluate the antimicrobial and antioxidant activity of AgNPs. The broad peak obtained at 411–475 nm (UV-Vis spectroscopy), and the color change pattern, confirmed the synthesis of AgNPs. TEM results showed spherical or rarely polygonal AgNPs with an average size of 44 nm at pH = 9. The AgNPs showed antioxidant activity and antibacterial effect against human pathogenic Gram-positive and Gram-negative bacteria. The results show that spruce bark extract is suitable for obtaining AgNPs, with antibacterial and antioxidant activity.

Green synthesis of gold nanoparticles by using Ferula persica Willd. gum essential oil: production, characterization and in vitro anti-cancer effects.

Abstract: OBJECTIVES Synthesizing and characterization of gold nanoparticles (Au NPs) by Ferula persica gum essential oil and investigating in vitro anti-cancer effects. METHODS Characterization of NPs was performed. Cytotoxicity and apoptosis were determined on cancerous CT26 and non-cancerous Vero cells using MTT assay and acridine orange/ethidium bromide (AO/EB) staining, respectively. Clonogenic assay was also performed. KEY FINDINGS The absorption peak in UV-visible spectroscopy was at 530 nm. In TEM image, Au NPs were spherical in shape with average size of 37.05 nm (78.6 nm in DLS analysis). Comparison of the FTIR spectrum of the Au NPs with the essential oil revealed the presence of compounds responsible for reducing and capping the gold ions. XRD pattern showed metal crystal structure. Au NPs exerted dose-dependent cytotoxicity with IC50 values of 0.0024 and 0.0307 mg/ml against CT26 and Vero cell lines, respectively. Au NPs induced apoptosis on both cell lines with statistically more intense effect on CT26 cells (P < 0.0001). Colony formation of CT26 and Vero cells was also inhibited in comparison to untreated cells (P < 0.05). CONCLUSIONS Ferula persica gum can be successfully used for green production of Au NPs. Au NPs show in vitro anti-cancer activity including cytotoxic, apoptotic and antiproliferative effects.

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

Abstract: 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.