S argassum muticum-synthesized silver nanoparticles: an effective control tool against mosquito vectors and bacterial pathogens.
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.
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Pari
P
Madhiyazhagan
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Kadarkarai
K
Murugan
Department of Zoology, Periyar University, Salem, 636011, Tamil Nadu, India.
Arjunan Naresh
AN
Kumar
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.|National Institute of Plant Health Management, Ministry of Agriculture, Hyderabad, India.
Thiyagarajan
T
Nataraj
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Devakumar
D
Dinesh
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Chellasamy
C
Panneerselvam
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Jayapal
J
Subramaniam
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Palanisamy
P
Mahesh Kumar
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Udaiyan
U
Suresh
Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India.
Mathath
M
Roni
Department of Environmental Biology, University Sapienza of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
Marcello
M
Nicoletti
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Abdullah A
AA
Alarfaj
Department of Reproduction, National Research Institute for Child Health and Development, Tokyo, 157-8535, Japan.
Akon
A
Higuchi
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
Murugan A
MA
Munusamy
Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124, Pisa, Italy. g.benelli@sssup.it.
Giovanni
G
Benelli
D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D009033:Culicidae / Q000187:drug effects* / Q000254:growth & development; D007306:Insecticides / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D053768:Metal Nanoparticles / Q000737:chemistry*; D009032:Mosquito Control / Q000379:methods; D018515:Plant Leaves / Q000737:chemistry; D011679:Pupa / Q000187:drug effects / Q000254:growth & development; D044647:Sargassum / Q000378:metabolism*; D012834:Silver / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D020349:Surface Plasmon Resonance
D000900:Anti-Bacterial Agents; D007306:Insecticides; D012834:Silver
Aedes aegypti; Anopheles stephensi; Bacillus subtilis; Culex quinquefasciatus; Klebsiella pneumoniae; Mosquitocidal activity; Ovideterrence; Salmonella typhi