Kanchi Subramanian Shivashangari

Origanum vulgare mediated biosynthesis of silver nanoparticles for its antibacterial and anticancer activity

In the present study, we achieved silver nanoparticles using the aqueous extract of Origanum vulgare (Oregano) by reducing 1mM silver nitrate (AgNO3) solution. The green synthesized silver nanoparticles were characterized by high throughput techniques like UV-vis spectroscopy, Fourier infrared spectroscopy (FT-IR), field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and dynamic light scattering measurements. Morphologically, the nanoparticles were found to be spherical with an average particle size distribution of 136±10.09nm. FT-IR spectral analysis illustrates the occurrence of possible biomolecules required for the reduction of silver ions. The obtained nanoparticles were stable (-26±0.77mV) at ambient temperature. The biosynthesized nanoparticles were found to be impressive in inhibiting human pathogens. The green synthesized silver nanoparticles showed dose dependent response against human lung cancer A549 cell line (LD50 - 100μg/ml).

Green synthesis of colloidal copper oxide nanoparticles using Carica papaya and its application in photocatalytic dye degradation.

Copper oxide (CuO) nanoparticles were synthesized by treating 5 mM cupric sulphate with Carica papaya leaves extract. The kinetics of the reaction was studied using UV-visible spectrophotometry. An intense surface Plasmon resonance between 250-300 nm in the UV-vis spectrum clearly reveals the formation of copper oxide nanoparticles. The results of scanning electron microscopy (SEM) and dynamic light scattering (DLS) exhibited that the green synthesized copper oxide nanoparticles are rod in shape and having a mean particle size of 140 nm, further negative zeta potential disclose its stability at -28.9 mV. The Fourier-transform infrared (FTIR) spectroscopy results examined the occurrence of bioactive functional groups required for the reduction of copper ions. X-ray diffraction (XRD) spectra confirmed the copper oxide nanoparticles crystalline nature. Furthermore, colloidal copper oxide nanoparticles effectively degrade the Coomassie brilliant blue R-250 dye beneath the sunlight.

Anticancer activity of Ficus religiosa engineered copper oxide nanoparticles

The design, synthesis, characterization and application of biologically synthesized nanomaterials have become a vital branch of nanotechnology. There is a budding need to develop a method for environmentally benign metal nanoparticle synthesis, that do not use toxic chemicals in the synthesis protocols to avoid adverse effects in medical applications. Here, it is a report on an eco-friendly process for rapid synthesis of copper oxide nanoparticles using Ficus religiosa leaf extract as reducing and protecting agent. The synthesized copper oxide nanoparticles were confirmed by UV-vis spectrophotometer, absorbance peaks at 285 nm. The copper oxide nanoparticles were analyzed with field emission-scanning electron microscope (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD) spectrum. The FE-SEM and DLS analyses exposed that copper oxide nanoparticles are spherical in shape with an average particle size of 577 nm. FT-IR spectral analysis elucidates the occurrence of biomolecules required for the reduction of copper oxide ions. Zeta potential studies showed that the surface charge of the formed nanoparticles was highly negative. The XRD pattern revealed that synthesized nanoparticles are crystalline in nature. Further, biological activities of the synthesized nanoparticles were confirmed based on its stable anti-cancer effects. The apoptotic effect of copper oxide nanoparticles is mediated by the generation of reactive oxygen species (ROS) involving the disruption of mitochondrial membrane potential (Δψm) in A549 cells. The observed characteristics and results obtained in our in vitro assays suggest that the copper nanoparticles might be a potential anticancer agent.

Effect of Tridax procumbens on liver antioxidant defense system during lipopolysaccharide-induced hepatitis in D-galactosamine sensitised rats

The present study was carried out to assess the effect of chloroform insoluble fraction of ethanolic extract of Tridax procumbens (TP) against D-Galactosamine/Lipopolysaccharide (D-GalN/LPS)-induced hepatitis in rats. Induction of rats with D-GalN/LPS (300 mg/kg body weight/30 μg/kg body weight) led to a marked increase in lipid peroxidation as measured by thiobarbituric acid reactive substances (TBARS) in liver. Further there was a decline in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione s-transferase and the levels of non-enzymic antioxidants namely reduced glutathione, vitamin C and vitamin E. These biochemical alterations were normalised upon pretreatment with TP extract. Thus, the above results suggest that TP (300 mg/kg body weight orally for 10 days) is very effective in allievating the D-GalN/LPS-induced oxidative stress suggesting its antioxidant property. (Mol Cell Biochem 269: 131–136, 2005)

Inhibition of pathogenic bacterial growth on excision wound by green synthesized copper oxide nanoparticles leads to accelerated wound healing activity in Wistar Albino rats

An impaired wound healing is one of the major health related problem in diabetic and non-diabetic patients around the globe. The pathogenic bacteria play a predominant role in delayed wound healing, owing to interaction in the wound area. In our previous work we developed green chemistry mediated copper oxide nanoparticles using Ficus religiosa leaf extract. In the present study we make an attempt to evaluate the anti-bacterial, and wound healing activity of green synthesized copper oxide nanoparticles in male Wistar Albino rats. The agar well diffusion assay revealed copper oxide nanoparticles have substantial inhibition activity against human pathogenic strains such as Klebsiella pneumoniae, Shigella dysenteriae, Staphylococcus aureus, Salmonella typhimurium and Escherichia coli, which were responsible for delayed wound healing process. Furthermore, the analyses results of wound closure, histopathology and protein profiling confirmed that the F. religiosa leaf extract tailored copper oxide nanoparticles have enhanced wound healing activity in Wistar Albino rats.Graphical Abstract

Evaluation of the Protective Efficacy of Asteracantha longifolia on Acetaminophen-Induced Liver Damage in Rats

The effect of oral administration of methanolic extract of Asteracantha longifolia (AL) seeds on acetaminophen (APAP)-induced acute liver damage in rats was investigated. The activities of marker enzymes (aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase, and gamma glutamyl transferase) and bilirubin level in serum and the levels of cholesterol, triglycerides, and free fatty acids in both serum and liver were found to be increased when rats were challenged with APAP. This was also associated with a significant reduction of serum and tissue phospholipids. Pretreatment with AL extract prior to the administration of APAP prevented these alterations as evidenced by liver histopathology. Results indicated that the extract could offer protection against APAP-induced liver damage, suggesting its hepatoprotective activity.

Integrated poly-D,L-lactide-co-glycolide/silver nanocomposite: synthesis, characterization and wound healing potential in Wistar Albino rats

Over the past few centuries, interest in novel metal nanoparticles has expanded quickly with the inclusion of new nanocomposites into a variety of products and technologies. Recently, nanocomposites prepared by the distribution of inorganic nanoparticles in polymeric matrices have found a prominent role in biomedical applications. In this report, we attempt to formulate a biodegradable poly-D,L-lactide-co-glycolide (PLGA) polymer based biogenic silver nanocomposite using a modified solvent casting method. The silver nanoparticles mediated by Origanum vulgare aqueous leaf extract (Ag NPs) and formulated silver polymeric nanocomposite (PLGA/Ag NC) show absorbance spectra at 420 nm under UV-visible spectroscopy. Fourier transform infrared spectroscopy confirms that Ag NPs utilized the carbonyl functional group present in the PLGA polymer for the successful formation of PLGA/Ag NC. Scanning electron microscopy analysis notably showed that PLGA/Ag NC was found to be spherical and irregular in shape, distributed in the polymer matrix. A dynamic light scattering measurement showed that PLGA/Ag NC has an average particle size distribution of 115 nm, and the zeta potential was −33 mV. The PLGA/Ag NC crystalline nature was confirmed using X-ray diffraction analysis. Furthermore, PLGA/Ag NC improves wound healing in the excision wound which was established using wound closure, histopathology, protein profiling, and matrix metalloproteinases 2 and 9 expression. The analysis results clearly show that PLGA/Ag NC enhances the wound healing activity by the sustained release of Ag NPs, upregulates protein expression and inhibits pathogenic bacterial growth in the wound area. In conclusion, PLGA/Ag NC could be a novel therapeutic agent for wound treatment.