Main content area

Biosynthesis, mosquitocidal and antibacterial properties of Toddalia asiatica-synthesized silver nanoparticles: do they impact predation of guppy Poecilia reticulata against the filariasis mosquito Culex quinquefasciatus?

Murugan, Kadarkarai, Venus, Joseph Selvaraj Eugine, Panneerselvam, Chellasamy, Bedini, Stefano, Conti, Barbara, Nicoletti, Marcello, Sarkar, Santosh Kumar, Hwang, Jiang-Shiou, Subramaniam, Jayapal, Madhiyazhagan, Pari, Kumar, Palanisamy Mahesh, Dinesh, Devakumar, Suresh, Udaiyan, Benelli, Giovanni
Environmental science and pollution research international 2015 v.22 no.21 pp. 17053-17064
Bacillus subtilis, Culex quinquefasciatus, Fourier transform infrared spectroscopy, Klebsiella pneumoniae, Poecilia reticulata, Salmonella Typhi, X-ray diffraction, agar, antibacterial properties, biosynthesis, developing countries, energy-dispersive X-ray analysis, field experimentation, filariasis, fish, insect larvae, instars, leaves, lethal concentration 50, minimum inhibitory concentration, mosquito-borne diseases, nanoparticles, nanosilver, natural enemies, parasites, pathogens, people, population, predation, pupae, scanning electron microscopy, surface plasmon resonance, toxicity
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 study, silver nanoparticles (AgN) were biosynthesized a cheap aqueous extract of T. asiatica leaves as reducing and stabilizing agent. The formation of nanoparticle was confirmed by surface Plasmon resonance band illustrated in UV–vis spectrophotometer. AgN were characterized by FTIR, SEM, EDX, and XRD analyses. AgN were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and their mean size was 25–30 nm. T. asiatica aqueous extract and green-synthesized AgN showed excellent larvicidal and pupicidal toxicity against the filariasis vector Culex quinqufasciatus, both in laboratory and field experiments. AgN LC₅₀ ranged from 16.48 (I instar larvae) to 31.83 ppm (pupae). T. asiatica-synthesized were also highly effective in inhibiting growth of Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. Lastly, we evaluated if sublethal doses of nanoparticles affect predation rates of fishes, Poecilia reticulata, against C. quinquefasciatus. In AgN-contaminated environment, predation of guppies against mosquito larvae was slightly higher over normal laboratory conditions. Overall, this study highlighted that T. asiatica-synthesized AgN are easy to produce, stable over time, and may be employed at low dosages to reduce populations of filariasis vectors, without detrimental effects on predation rates of mosquito natural enemies.