S. Rajeshkumar

Mechanistic study on antibacterial action of zinc oxide nanoparticles synthesized using green route

A large array of diseases caused by bacterial pathogens and origination of multidrug resistance in their gene provokes the need of developing new vectors or novel drug molecules for effective drug delivery and thus, better treatment of disease. The nanoparticle has emerged as a novel drug molecule in last decade and has been used in various industrial fields like cosmetics, healthcare, agricultural, pharmaceuticals due to their high optical, electronic, medicinal properties. Use of nanoparticles as an antibacterial agent remain in current studies with metal nanoparticles like silver, gold, copper, iron and metal oxide nanoparticles like zinc oxide, copper oxide, titanium oxide and iron oxide nanoparticles. The high anti-bacterial activity of nanoparticles is due to their large surface area to volume ratio which allows binding of a large number of ligands on nanoparticle surface and hence, its complexation with receptors present on the bacterial surface. Green synthesis of Zinc Oxide Nanoparticle (ZnO NP) and its anti-bacterial application has been particularly discussed in the review literature. The present study highlights differential nanoparticle attachment to gramxa0+xa0and gram - bacterial surface and different mechanism adopted by nanoparticle for bacterial control. Pharmacokinetics and applications of ZnO NP are also discussed briefly.

Plant-Based Synthesis of Nanoparticles and Their Impact

Abstract Plants are the major sources of different types of phytochemicals with numerous biomedical applications. Nanotechnology is a rapidly growing field and plays an important role in most of the advanced science, medicine, and technology areas. This chapter summarizes the plant sources used for nanoparticle synthesis, characterization, and their applications. Plant parts such as leaves, fruits, seeds, stems, flowers, roots, barks, and fruit peels are involved in the synthesis of various types of nanoparticles. The low cost and higheco-friendly-natured plants are very advanced and beneficial to human applications. Nanoparticles such as silver from silver nitrate, gold from gold chloride, zinc oxide from zinc nitrate and zinc acetate, cadmium sulfide and zinc sulfide from cadmium sulfate and zinc sulfate, etc. were synthesized with the help of different types of plants and their different parts are reported in this chapter.

Biosynthesis of zinc oxide nanoparticles using Mangifera indica leaves and evaluation of their antioxidant and cytotoxic properties in lung cancer (A549) cells

Green synthesis is an eco-friendly approach to nanoparticle production, which eliminates the use of toxic chemicals, high temperatures, and costly equipment needed for traditional physical and chemical synthesis methods. This eco-friendly approach was used in the present study to biosynthesize zinc oxide nanoparticles (ZnO NPs) from Mangifera indica (mango) leaves which were then evaluated for their antioxidant activity and cytotoxic effects on lung cancer A549 cells. Synthesized ZnO nanoparticles were characterized using UV-vis spectroscopy, XRD, SEM, and EDX analyses. The XRD and SEM analyses showed 45-60u202fnm as the size of synthesized nanoparticles, the pure crystal form of ZnO NPs, and the shape of the NPs as nearly spherical and hexagonal quartzite. The antioxidant potential of nanoparticles was estimated using a DPPH free radical scavenging assay. The percent of viable cells was inversely proportional to the concentration of ZnO nanoparticles at 25u202fμg/mL concentration. The MTT assay used for cytotoxicity evaluation depicted the significant cytotoxic effect of ZnO NPs against the A549 lung cancer cell line. The drop in the proportion of viable A549 cells after exposure to ZnO NPs was comparable to the effects of the standard drug used i.e. cyclophosphamide. Antioxidant activity of NPs was increased by increasing the concentration of NPs. The present biosynthesis approach is rapid, inexpensive and eco-friendly and it yielded highly stable ZnO NPs with significant antioxidant and anticancer potential. This is the first report of M. indicia -mediated synthesis of ZnO NPs as antioxidant and, anticancer agents for the treatment of lung cancer and subsequent therapeutic applications.

Selenium nanoparticles: A potent chemotherapeutic agent and an elucidation of its mechanism

Selenium nanoparticles have at present picked up a vital prospect in the field of medicine, due to their inquisitive properties when compared to other selenium compounds. They are comparatively better as anticancer, non- toxic, and biocompatible operators than selenite (SeO3-2) and selenate (SeO4-2) compounds. The mechanism behind the anticancerous property of SeNps is primarily due to the invasion of the apoptotic pathways and cell cycle arrest, which eventually lead to blockage of other pathways. Conjugation or surface modification of selenium nanoparticles enhances its anticancer adequacy by antibiotics, biomolecules or phytochemical compounds present in microbes or plants. Selenium, being an integral part of enzyme like glutathione peroxidase (GPx) and other seleno-chemical compounds, can enhance the chemotherapeutic activity by acting as a functional division of redox center and inhibiting the tissues from cellular damage by ROS. SeNps can open ways to new regular strategies for treating illnesses like malignancy, and this audit expresses the reasons why these nano measured medications can be the following huge achievement as chemotherapeutic operators.

Phyto-Assisted Synthesis of Silver Nanoparticles using Solanum Nigrum and Antibacterial Activity Against Salmonella Typhi and Staphylococcus Aureus

This study aims to provide a simple and eco-friendly approach for the synthesis of Ag NPs using medicinal plant Solanum nigrum aqueous leaf extract. Fresh leaf extract mediated the reduction of silver from higher excited state to the ground extract when mixed with 1 mM silver nitrate solution. Reduction led the synthesis of silver nanoparticle with the size range of 20-40 nm was confirmed by TEM analysis. UV-Vis analysis demonstrates the synthesis of Ag NPs by its standard peak due to SPR (Surface Plasmon Resonance). XRD analysis confirmed the crystalline nature of Ag NPs. It was further characterized by FT-IR for the confirmation of functional groups responsible for Ag NPs synthesis and elements analyzed using EDX. Our study also showed the high antibacterial effect of nanoparticle against disease causing virulent bacterial strains (Salmonella typhi and Staphylococcus aureus).

Evaluation of antibacterial, antioxidant and GC-MS analysis of ethanolic seed extract of Myristica dactyloides

In this present investigation we analysed the antimicrobial and antioxidant activities of ethanol extract of Myristica dactyloides. The antimicrobial activity of the ethanol extract was evaluated by the agar well diffusion method against of E. coli, Klebsiella pneumonia, Streptococcus sp, and Staphylococcus aureus at different concentrations. The antibacterial activity showed the result in a dose-dependent manner. The free radical scavenging was evaluated against DPPH, hydroxyl, and nitric oxide radicals. In DPPH, hydroxyl and nitric oxide scavenging assay showed the IC 50 value of the extract was found to be 20 μg/ml, 48.25 and 30 μg/ml, respectively. The plant can be considered as promising antioxidant properties with high potential value for drug development for various diseases.