One-pot fabrication of silver nanocrystals using Ormocarpum cochinchinense: Biophysical characterization of a potent mosquitocidal and toxicity on non-target mosquito predators

Marimuthu Govindarajan,Giovanni Benelli 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.2

Mosquito vectors (Diptera: Culicidae) are vectors of pathogens and parasites of public health importance, including malaria, dengue, chikungunya, Japanese encephalitis, lymphatic filariasis and Zika virus. Novel eco-friendly control tools against Culicidae are a priority. In this research, silver nanoparticles (Ag NPs) were rapidly synthesized using the aqueous leaf extract of Ormocarpum cochinchinense as a cheap, non-toxic material. The bioreduced Ag NPs were characterized by UV–visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDX) and X-ray diffraction analysis (XRD). The acute toxicity of O. cochinchinense leaf extract and synthesized Ag NP 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, synthesized Ag NPs showed high toxicity against A. stephensi, A. aegypti and C. quinquefasciatus, with LC50 values of 10.43, 11.26 and 12.35 μg/mL, respectively. Synthesized Ag NPs were found safer to non-target mosquito predators Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 522.13 to 637.70 μg/mL. Overall, this study firstly shed light to O. cochinchinense's potential as a bioresource for rapid, cheap and effective nanosynthesis of mosquitocides.

Clerodendrum chinense-mediated biofabrication of silver nanoparticles: Mosquitocidal potential and acute toxicity against non-target aquatic organisms

Marimuthu Govindarajan,Mohan Rajeswary,S.L. Hoti,Kadarkarai MURUGAN,Kalimuthu Kovendan,Subramanian Arivoli,Giovanni Benelli 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.1

Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to high operational costs and adverse non-target effects. Plantborne compounds have been proposed for rapid extracellular synthesis ofmosquitocidal nanoparticles. Their impact against biological control agents of mosquito larval populations has been poorly studied. In this study, we synthesized silver nanoparticles (Ag NPs) using the Clerodendrumchinense leaf extract as reducing and stabilizing agent. The biosynthesis of AgNP was confirmed analyzing the excitation of surface Plasmon resonance using ultraviolet–visible (UV–vis) spectrophotometry. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the clustered and irregular shapes of Ag NP. The presence of silver was determined by energy dispersive X-ray (EDX) spectroscopy. Fourier transform infrared (FTIR) spectroscopy analysis investigated the identity of secondary metabolites,which may act as Ag NP capping agents. The acute toxicity of C. chinense leaf extract and biosynthesized Ag NP was evaluated against larvae of Anopheles subpictus, Aedes albopictus and Culex tritaeniorhynchus. Compared to the leaf aqueous extract, biosynthesized Ag NP showed higher toxicity against A. subpictus, A. albopictus, and C. tritaeniorhynchus with LC50 values of 10.23, 11.10 and 12.38 μg/mL, respectively. Biosynthesized Ag NPswere found safer to non-target organisms Diplonychus indicus, Anisops bouvieri and Gambusia affinis, with respective LC50 values ranging from647.05 to 6877.28 μg/ml. Overall, our results highlight that C. chinense-fabricated Ag NP are a promising and eco-friendly tool against larval populations ofmosquito vectors of medical and veterinary importance, with negligible toxicity against non-target aquatic organisms. © 2015 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection

Size-controlled biofabrication of silver nanoparticles using the Merremia emarginata leaf extract: Toxicity on Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) and non-target mosquito predators

Raja Mohamed Sait Thameem Azarudeen,Marimuthu Govindarajan,Mashael Marzouq AlShebly,Fatma Saeed AlQahtani,Abubucker Amsath,Sengamalai Senthilmurugan,Periasamy Vijayan,Giovanni Benelli 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

Mosquito-borne diseases represent a major human and animal health problem in all tropical and subtropical countries worldwide. The synthesis of eco-friendly metal nanoparticles is a fast-growing branch of current nanoscience with a number of biomedical and entomological implications. In this study, we investigated the one-pot synthesis of silver nanoparticles (Ag NPs) using a cheap leaf extract of Merremia emarginata (Convolvulaceae). Bio-reduced Ag NPs were characterized by UV–visible spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction analysis, atomic force microscopy, scanning electron microscopy and transmission electron microscopy. SEM, TEM and AFM morphological nanocharacterization showed that this synthesis led to the production of size-controlled Ag NPs, ranging from 25 to 65 nm. The acute toxicity of M. emarginata leaf extract and biosynthesized Ag NPs was evaluated against third instar larvae of the malaria vector Anopheles stephensi, the dengue and Zika virus vector Aedes aegypti and the filariasis vector Culex quinquefasciatus. Compared to the leaf aqueous extract, Ag NPs showed higher toxicity against A. stephensi, A. aegypti, and C. quinquefasciatus with LC50 values of 8.36, 9.20 and 10.02 μg/mL, respectively. M. emarginata-fabricated Ag NPs were found safer to non-target aquatic biocontrol agents Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 ranging from 415.61 to 25,153.46 μg/mL. However, although it has been proven the AgNPs fabricated in the present study are more effective if compared to the crude M. emarginata extract, they still exert some toxicity on biocontrol agents, thus further research is required to produce more eco-friendly formulations for field purposes.

Green and facile biosynthesis of silver nanocomposites using the aqueous extract of Rubus ellipticus leaves: Toxicity and oviposition deterrent activity against Zika virus, malaria and filariasis mosquito vectors

Fatma Saeed AlQahtani,Mashael Marzouq AlShebly,Marimuthu Govindarajan,Sengamalai Senthilmurugan,Periasamy Vijayan,Giovanni Benelli 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.1

Botanical-based nanosynthesis has been recently reported as a cheap alternative for mosquito management. In this study, we investigated the synthesis of silver nanoparticles (AgNPs) using the leaf extract of Rubus ellipticus and AgNPswere characterized using UV–vis spectroscopy, XRD, FTIR, SEM, TEMand EDX analyses. The toxicity of R. ellipticus leaf extract and AgNPs was evaluated against eggs, larvae and adults of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. Compared to the leaf aqueous extract, biosynthesized AgNPs showed higher toxicity against the mosquito larvae with LC50 values of 12.50, 13.83 and 15.09 μg/mL, respectively. AgNPs exerted zero hatchability at 60, 75 and 90 μg/mL on A. stephensi, A. aegypti, and C. quinquefasciatus, respectively. Concentrations of 12–60 μg/mL reduced egg laying by gravid females from72.28 to 91.48%.Maximumadulticidal efficacywas observed for AgNPs,with LD50 values were 21.10, 23.04 and 25.06 μg/mL, respectively. AgNPs were found safer to non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 896 to 2261 μg/mL. Overall, R. ellipticus-fabricated AgNPs acted as effective toxic agents and ovideterrents against three important mosquitoes species, with little harmful effects on non-target aquatic species.

Green-synthesized silver nanoparticles using Psychotria nilgiriensis: toxicity against the dengue vector Aedes aegypti (Diptera: Culicidae) and impact on the predatory efficiency of the non-target organism Poecilia sphenops (Cyprinodontiformes: Poeciliid

Kalimuthu Kovendan,Balamurugan Chandramohan,Devakumar Dinesh,Dhandapani Abirami,Periasamy Vijayan,Marimuthu Govindarajan,Savariar Vincent,Giovanni Benelli 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.4

Mosquitoes transmit serious diseases to humans and animals, causingmillions of deaths every year. Effective insecticides of natural origin for eco-friendly vector control are a priority. In this study, silver nanoparticles (AgNPs) biosynthesized using as cheap Psychotria nilgiriensis leaf extractwere tested on larvae and pupae of Aedes aegypti (Diptera: Culicidae). Biophysical characterizationwas carried outwith UV–vis spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24 h. The maximum mortality was observed for green-synthesized AgNPs. Moreover, the combined treatment of leaf extract of P. nilgiriensis and AgNPs lowered the plant extract LC50 to 92.87, 115.27, 140.37, 169.30 and 212.55 μg/ml. The effectiveness of green synthesized AgNPs was confirmed against eggs and adults of A. aegypti. Furthermore, we showed that the predatory efficiency of Poecilia sphenops on A. aegypti was not reduced after the exposure at sublethal doses of AgNPs. Predation in the control was 65% (larva I) and 49.62% (larva II). Predation against late-instar larvae was minimal. In AgNPs-treated environment (3 ppm), predation was boosted to 90.25% (larva I) and 76.50% (larva II), respectively. Overall, P. nilgiriensis-synthesized AgNPs could be proposed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of P. sphenops.

Green synthesis and biophysical characterization of silver and palladium nanoparticles using Laureliopsis philippiana: A potent eco-friendly larvicide with negligible impact on zebrafish (Danio rerio)

Kamaraj Chinnaperumal,Naveenkumar Selvam,Prem Pradisha,Ragavendran Chinnasamy,Subramaniyan Vetriselvan,Al-Ghanim Khalid A.,Malafaia Guilherme,Nicoletti Marcello,Govindarajan Marimuthu 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.4

Green nanoparticles represent a sustainable and eco-friendly approach to developing larvicides targeted at controlling mosquito populations. These nanoparticles are synthesized using natural, non-toxic materials and environmentally benign processes, emphasizing their potential to combat mosquito larvae while minimizing adverse effects on the ecosystem. This approach aligns with the growing need for sustainable solutions in vector control, providing an effective alternative to traditional larvicides with reduced environmental impact. The aim of the present investigation we have utilized the leaf from Laureliopsis philippiana (LP) to synthesize silver (Ag) and palladium (Pd) nanoparticles (NPs) and studied toxicity on deadly disease vectors larvae of Aedes aegypti and Anopheles stephensi. Biosynthesized Ag and Pd NPs were extensively characterized through physical and chemical methods. Gas chromatography–mass spectrometry analysis of L. philippiana assisted in identifying the secondary metabolites of the extract’s total flavonoid and phenolic compounds, which are in the reactants of the bioreduction process during the production of NPs. The in-silico analysis was conducted on mosquito sterol car rier protein-2 (1PZ4) and mosquito odorant binding protein (2L2C). The biosynthesized Ag and Pd NPs revealed the UV absorption peak at 417 and 370 nm, and X-ray diffraction results showed the crystalline structure of NPs. At the same time, in transmission electron microscopy representation, the Ag and Pd NPs were spherical, clus tered, and exhibited a noticeable average size of Ag NPs: 13.25 ± 2.53 nm and Pd NPs: 4.07 ± 1.64 nm. The biogenic Ag and Pd NPs showed concentration-dependent larvicidal mortality at 12 and 24-hour exposure with LC 50 values of 29.596, 17.804, and 23.915, 14.878 µg/mL on Ae. aegypti and 23.946, 13.938, 19.457, and 12.876 µg/mL against An. stephensi, correspondingly. In-silico studies proved that Laureliopsine A and isoterpinolene showed significant docking scores compared to permethrin on mosquito proteins (1PZ4 and 2L2C). Besides, the LP-Ag and Pd NPs non-toxicity analysis was carried out on zebrafish (Danio rerio) embryos at 72 h post- * Corresponding authors. E-mail addresses: kamarajc@srmist.edu.in (C. Kamaraj), guilhermeifgoiano@gmail.com (G. Malafaia). https://doi.org/10.1016/j.aspen.2023.102164 Received 31 August 2023; Received in revised form 9 October 2023; Accepted 11 October 2023 Available online 13 October 2023 1226-8615/© 2023 Korean Society of Applied Entomology. Published by Elsevier B.V. All rights reserv