Bharathiar University

About: Bharathiar University is a education organization based out in Coimbatore, Tamil Nadu, India. It is known for research contribution in the topics: Thin film & Adsorption. The organization has 5812 authors who have published 8628 publications receiving 143934 citations. The organization is also known as: BU.

S argassum muticum-synthesized silver nanoparticles: an effective control tool against mosquito vectors and bacterial pathogens

Abstract: Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Furthermore, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. In this research, silver nanoparticles (AgNP) were synthesized using the aqueous extract of the seaweed Sargassum muticum. The production of AgNP was confirmed by surface plasmon resonance band illustrated in UV–vis spectrophotometry. AgNP were characterized by FTIR, SEM, EDX, and XRD analyses. AgNP were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and mean size was 43–79 nm. Toxicity of AgNP was assessed against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. In laboratory, AgNP were highly toxic against larvae and pupae of the three mosquito species. Maximum efficacy was observed against A. stephensi larvae, with LC50 ranging from 16.156 ppm (larva I) to 28.881 ppm (pupa). In the field, a single treatment with AgNP (10 × LC50) in water storage reservoirs was effective against the three mosquito vectors, allowing complete elimination of larval populations after 72 h. In ovicidal experiments, egg hatchability was reduced by 100 % after treatment with 30 ppm of AgNP. Ovideterrence assays highlighted that 10 ppm of AgNP reduced oviposition rates of more than 70 % in A. aegypti, A. stephensi, and C. quinquefasciatus (OAI = −0.61, −0.63, and −0.58, respectively). Antibacterial properties of AgNP were evaluated against Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. AgNP tested at 50 ppm evoked growth inhibition zones larger than 5 mm in all tested bacteria. Overall, the chance to use S. muticum-synthesized AgNP for control of mosquito vectors seems promising since they are effective at low doses and may constitute an advantageous alternative to build newer and safer mosquito control tools. This is the first report about ovicidal activity of metal nanoparticles against mosquito vectors.

Effect of Biopesticides Applied Separately or Together on Nutritional Indices of the Rice Leaffolder Cnaphalocrocis medinalis

Abstract: Laboratory assays were done to evaluate the effect of neem seed kernel extract (Azadirachta indica A. Juss),Vitex negundo L. (Lamiales: Verbenaceae) leaf extract, andBacillus thuringiensis (Berliner), applied separately or together, on nutritional indices of the rice leaffolderCnaphalocrocis medinalis (Guenee) (Lepidoptera: Pyralidae). All three biopesticides suppressed feeding and larval growth and low concentrations affected the larval performance. The combined effect of the three biopesticides resulted in a considerable decrease in nutritional indices, indicating strong deterrence. Dose response relationships were established with respect to frass production and larval growth. The efficiency of conversion of ingested and digested food was considerably reduced.

Biosynthesis and characterization of copper oxide nanoparticles from indigenous fungi and its effect of photothermolysis on human lung carcinoma.

Abstract: In this report, copper oxide nanoparticles (TA-CuO NPs) were synthesized using cell-free extract of Trichoderma asperellum and assessed their photothermal induced anticancerous activity. The fungal mediated TA-CuO NPs was confirmed by the surface plasmon resonance at 285–295 nm. The amide (C O) and aromatic (C C) groups in secondary metabolites of the extract was found to be an encapsulating or reducing agents for TA-CuO NPs, as indicated by IR spectra. Crystalline nature by cubic face-centered structure of the TA-CuO NPs was confirmed by XRD and their size ranges from 10 to 190 nm and an average of 110 nm by particle size analyzer (PSA). The Ultra HRSEM study revealed spherical shaped TA-CuO NPs. The FETEM results were also in strong agreement with PSA and UHR SEM. The survey-scan spectrum of XPS indicated the presence of C1s (47.83%), Cu2p (16.11%), Na1s (2.2%) and O1s (33.86%). The cell death was significantly found higher in photothermal induced by near-infrared laser (TA-CuO NPs-NIR) treated than that of TA-CuO NPs treatment. The level of ROS (35.62%) was higher in the treated cells than that of the untreated control, in accordance with the nucleus damage and losses in the mitochondrial membrane potential (ΔΨm). The upregulation of Bcl-2 in the untreated cells and Cas-3 in TA-CuO NPs-NIR treated cells was confirmed by western blot analysis. This work agreed with the potential biogenic TA-CuO NPs for promising in vitro photothermolysis of cancer cells, for the development of anticancer nanotherapeutics.