title: One-step synthesis of polydispersed silver nanocrystals using Malva sylvestris: an eco-friendly mosquito larvicide with negligible impact on non-target aquatic organisms.
abstract: The synthesis of eco-friendly nanoparticles is evergreen branch of nanoscience with a growing number of biomedical implications. In this study, we investigated the synthesis of polydisperse and stable silver nanoparticles (AgNP) using a cheap leaf extract of Malva sylvestris (Malvaceae). Bio-reduced AgNP were characterized by UV-visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The acute toxicity of M. sylvestris leaf extract and green-synthesized AgNP was evaluated against larvae of the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the filariasis vector Culex quinquefasciatus. Compared to the leaf aqueous extract, AgNP showed higher toxicity against A. stephensi, A. aegypti, and C. quinquefasciatus with LC50 values of 10.33, 11.23, and 12.19 μg/mL, respectively. Green-synthesized AgNP were found safer to non-target organisms Diplonychus indicus and Gambusia affinis, with respective LC50 values ranging from 813.16 to 1044.52 μg/mL. Overall, this research firstly shed light on the mosquitocidal potential of M. sylvestris, a potential bio-resource for rapid, cheap and effective synthesis of polydisperse and highly stable silver nanocrystals.
authors.affiliation: Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, 608 002, Tamil Nadu, India. drgovindzoo@yahoo.com.
authors.forename: Marimuthu
authors.initials: M
authors.lastname: Govindarajan
authors.affiliation: Regional Medical Research Centre, Nehru Nagar, Belgaum, 590010, Karnataka, India.
authors.forename: S L
authors.initials: SL
authors.lastname: Hoti
authors.affiliation: Unit of Vector Control, Phytochemistry and Nanotechnology, Department of Zoology, Annamalai University, Annamalainagar, 608 002, Tamil Nadu, India.
authors.forename: Mohan
authors.initials: M
authors.lastname: Rajeswary
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; D000818:Animals; D000852:Anopheles / Q000187:drug effects; D059001:Aquatic Organisms; D003465:Culex / Q000187:drug effects; D009033:Culicidae / Q000187:drug effects*; D005260:Female; D007306:Insecticides / Q000737:chemistry; D007814:Larva / Q000187:drug effects; D028501:Malva / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D012834:Silver / Q000737:chemistry*
chemical_list: D007306:Insecticides; D010936:Plant Extracts; D012834:Silver
keywords: Biosafety; Biosynthesis; Mosquito-borne diseases; Nanotechnology; Zika virus