Larvicidal activity of synthesized silver nanoparticles using Eclipta prostrata leaf extract against filariasis and malaria vectors

• Published in: Acta tropica Vol. 118; no. 3; pp. 196 - 203
• Main Authors: Rajakumar, G., Abdul Rahuman, A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01-06-2011; Elsevier
• Subjects: Animals; Anopheles - drug effects; Anopheles subpictus; Asteraceae; Biological and medical sciences; Culex - drug effects; Culex quinquefasciatus; Culex tritaeniorhynchus; Culicidae; Diptera; Diseases caused by nematodes; Eclipta; Eclipta - chemistry; Eclipta prostrata; Electron microscopic study; Filariases; filariasis; Fourier transform infrared spectroscopy; General aspects; Helminthic diseases; human diseases; Human protozoal diseases; Infectious diseases; insecticides; Insecticides - pharmacology; instars; Larva - drug effects; larvae; leaf extracts; Lymphatic filariases; Malaria; Medical sciences; Metal Nanoparticles; nanosilver; Parasitic diseases; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Plant Leaves - chemistry; Protozoal diseases; scanning electron microscopy; Silver - pharmacology; Silver nanoparticles; Survival Analysis; transmission electron microscopy; vector control; X-ray diffraction; X-ray diffraction analysis; Electron microscopic study; Anopheles subpictus; Eclipta prostrata; Silver nanoparticles; X-ray diffraction analysis; Culex quinquefasciatus; Protozoal disease; Malaria; Plant leaf; Parasitosis; Electron microscopy; Helminthiasis; Infection; Anatomic pathology; Nematode disease; Tropical medicine; Filariosis; Vector
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2011.03.003

The significant reduction in reaction time with Eclipta leaf is an important resultant and was enable nanoparticle biosynthesis methods to compete with other plant assisted biosynthesis. The formed silver nanoparticles were highly stable and showed significant mosquito larvicidal activity. The surface reactivity facilitated by capping enables these functionalized nanoparticles as promising candidates for various pharmaceutical, biomedical and environmental applications. [Display omitted]
► Larvicidal activity of synthesized silver nanoparticles utilizing aqueous extract from Eclipta prostrata was investigated against Culex quinquefasciatus and Anopheles subpictus. ► The synthesized AgNPs characterized by UV–vis spectrum, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared and X-ray diffraction. ► The maximum efficacy was observed in synthesized AgNPs against C. quinquefasciatus (LC50 = 4.56 mg/L; LC90 = 13.14 mg/L). ► The maximum efficacy was observed in synthesized AgNPs against A. subpictus (LC50 = 5.14 mg/L; LC90 = 25.68 mg/L). ► SEM analyses of the synthesized AgNPs were measured 35–60nm in size. ► FTIR identify the biomolecules responsible for the reduction of Ag+ ions.
Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In this study, larvicidal activity of synthesized silver nanoparticles (AgNPs) utilizing aqueous extract from Eclipta prostrata, a member of the Asteraceae was investigated against fourth instar larvae of filariasis vector, Culex quinquefasciatus say and malaria vector, Anopheles subpictus Grassi (Diptera: Culicidae). The synthesized AgNPs characterized by UV–vis spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD). SEM analyses of the synthesized AgNPs were clearly distinguishable measured 35–60nm in size. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24h. The maximum efficacy was observed in crude aqueous, and synthesized AgNPs against C. quinquefasciatus (LC50=27.49 and 4.56mg/L; LC90=70.38 and 13.14mg/L), and against A. subpictus (LC50=27.85 and 5.14mg/L; LC90=71.45 and 25.68mg/L) respectively. The chi-square value were significant at p<0.05 level. These results suggest that the synthesized AgNPs have the potential to be used as an ideal eco-friendly approach for the control of the Culex tritaeniorhynchus and A. subpictus. This method is considered as a new approach to control vectors. Therefore, this study provides first report on the mosquito larvicidal activity of synthesized AgNPs against vectors.