title: Characterization and mosquitocidal potential of neem cake-synthesized silver nanoparticles: genotoxicity and impact on predation efficiency of mosquito natural enemies.
abstract: Mosquitoes (Diptera: Culicidae) serve as important vectors for a wide number of parasites and pathogens of huge medical and veterinary importance. Aedes aegypti is a primary dengue vector in tropical and subtropical urban areas. There is an urgent need to develop eco-friendly mosquitocides. In this study, silver nanoparticles (AgNP) were biosynthesized using neem cake, a by-product of the neem oil extraction from the seed kernels of Azadirachta indica. AgNP were characterized using a variety of biophysical methods, including UV-vis spectrophotometry, FTIR, SEM, EDX, and XRD analyses. Furthermore, the neem cake extract and the biosynthesized AgNP were tested for acute toxicity against larvae and pupae of the dengue vector Ae. aegypti. LC50 values achieved by the neem cake extract ranged from 106.53 (larva I) to 235.36 ppm (pupa), while AgNP LC50 ranged from 3.969 (larva I) to 8.308 ppm (pupa). In standard laboratory conditions, the predation efficiency of a Carassius auratus per day was 7.9 (larva II) and 5.5 individuals (larva III). Post-treatment with sub-lethal doses of AgNP, the predation efficiency was boosted to 9.2 (larva II) and 8.1 individuals (larva III). The genotoxic effect of AgNP was studied on C. auratus using the comet assay and micronucleus frequency test. DNA damage was evaluated on peripheral erythrocytes sampled at different time intervals from the treatment; experiments showed no significant damages at doses below 12 ppm. Overall, this research pointed out that neem cake-fabricated AgNP are easy to produce, stable over time, and can be employed at low dosages to reduce populations of dengue vectors, with moderate detrimental effects on non-target mosquito natural enemies.
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Balamurugan
authors.initials: B
authors.lastname: Chandramohan
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Kadarkarai
authors.initials: K
authors.lastname: Murugan
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Chellasamy
authors.initials: C
authors.lastname: Panneerselvam
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Pari
authors.initials: P
authors.lastname: Madhiyazhagan
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Ramachandran
authors.initials: R
authors.lastname: Chandirasekar
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Devakumar
authors.initials: D
authors.lastname: Dinesh
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Palanisamy Mahesh
authors.initials: PM
authors.lastname: Kumar
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Kalimuthu
authors.initials: K
authors.lastname: Kovendan
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Udaiyan
authors.initials: U
authors.lastname: Suresh
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Jayapal
authors.initials: J
authors.lastname: Subramaniam
authors.affiliation: Division of Entomology, Department of Zoology, School of Life sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
authors.forename: Rajapandian
authors.initials: R
authors.lastname: Rajaganesh
authors.affiliation: Faculty of Science, Department of Biology, University of Tabuk, Tabuk, 71491, Saudi Arabia.
authors.forename: Al Thabiani
authors.initials: AT
authors.lastname: Aziz
authors.affiliation: Department of Ecosystem studies, School of Environmental Science, University of Shiga Prefecture, 2500 Hassaka-cho, Hikone, Shiga, 522-8533, Japan.
authors.forename: Ban
authors.initials: B
authors.lastname: Syuhei
authors.affiliation: Department of Physics and Astronomy, Research Chair in Laser Diagnosis of Cancer, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Mohamad Saleh
authors.initials: MS
authors.lastname: Alsalhi
authors.affiliation: Department of Physics and Astronomy, Research Chair in Laser Diagnosis of Cancer, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Sandhanasamy
authors.initials: S
authors.lastname: Devanesan
authors.affiliation: Department of Environmental Biology, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Nicoletti
authors.affiliation: Institute of Plant Protection, Fujian Academy of Agricultural Sciences, Fuzhou, 350013, Fujian, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wei
authors.affiliation: Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, 56124, Pisa, Italy. g.benelli@sssup.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Benelli
mesh_terms: D000330:Aedes / Q000187:drug effects / Q000235:genetics; D000818:Animals; D031601:Azadirachta / Q000737:chemistry*; D020552:Comet Assay; D004249:DNA Damage; D003715:Dengue / Q000635:transmission; D005989:Glycerides; D006054:Goldfish / Q000235:genetics / Q000502:physiology; D006801:Humans; D007302:Insect Repellents; D007303:Insect Vectors / Q000187:drug effects / Q000235:genetics; D007306:Insecticides / Q000494:pharmacology; D007814:Larva / Q000187:drug effects; D053768:Metal Nanoparticles / Q000633:toxicity; D015162:Micronucleus Tests; D010936:Plant Extracts / Q000494:pharmacology; D018515:Plant Leaves; D011235:Predatory Behavior / Q000187:drug effects; D011679:Pupa / Q000187:drug effects; D012834:Silver; D013729:Terpenes
chemical_list: D005989:Glycerides; D007302:Insect Repellents; D007306:Insecticides; D010936:Plant Extracts; D013729:Terpenes; D012834:Silver; C002443:neem oil
keywords: Arbovirus; Azadirachta indica; Biological control; Biosafety; Botanical byproduct; Dengue fever; Mosquito-borne disease; Nanobiotechnology