A comparative study on larvicidal potential of selected medicinal plants over green synthesized silver nano particles

Abstract

Larvicidal activity was assessed for alcoholic extracts of Phyllanthus amarus, Annona squamosa, Coccinia grandis and Eclipta prostrata extracted using solvents of various polarity. Third instar stage larvae of Dengue-vector, Aedes aegypti and Japanese encephalitis (JE) causing mosquito Culex tritaeniorhynchus were subjected to larvicidal bioassay at various concentrations (1000, 500, 250 ppm). The results explored that the phytoconstituents and secondary metabolites present in all the plants elucidated potent larvicidal activity. Among the tested extract ethyl acetate, petroleum ether and hexane extract expressed significant larvicidal activity. Similarly, these plants were subjected to green synthesis of silver nanoparticles, characterized and subjected for its larvicidal activity against Anopheles stephensi causing malaria. The synthesized silver nanoparticles were characterized by UV-VIS spectroscopy, Fourier Transform Infra-Red spectroscopy, Scanning Electron Microscopy respectively. The FTIR analysis strongly supported the capping behaviour of bio-reduced synthesized silver nanoparticles which in turn imparted the high stability of the synthesized silver nanoparticles. The average size of synthesized nanoparticles was less than 1 mm, most spherical in shape with SEM analysis. The findings revealed that Eclipta prostrata and Annona squamosa has effective larvicidal activity, whereas all the synthesised nanoparticles demonstrated dose dependent activity even at very low concentration and the findings reveals that these extracts and nanoparticles can be a better remedy against these mosquitoes.

Comparative study on larvicidal activity of green synthesized silver nanoparticles and Annona glabra (Annonaceae) aqueous extract to control Aedes aegypti and Aedes albopictus (Diptera: Culicidae)

“…0.1 g of green synthesized AgNPs (Plant extract: AgNO 3 ; 1:10) compound was dissolved by sonication in 1000 mL of deionized water to produce stock solutions of AgNPs (Plant extract: AgNO 3 ; 1:10). Concentrations of AgNPs (Plant extract: AgNO 3 ; 1:10) 0.002 g/L, 0.004 g/L, 0.006 g/L, 0.008 g/L and 0.01 g/L were prepared by micropipetting (Khader et al, 2017;Khader and Ramesh, 2018). One concentration was prepared by randomly selecting four beakers that each including 20 larvae and adding the required volume of AgNPs (Plant extract: AgNO 3 ; 1:10) solution into each beaker based on C 1 V 1 ¼ C 2 V 2 equation.…”

Efficacy of Antimicrobial and Larvicidal Activities of Green Synthesized Silver Nanoparticles Using Leaf Extract of Plumbago auriculata Lam

“…Vector-borne diseases transmitted by mosquitoes that result in malaria, dengue fever, filariasis, ticks, fleas, and other vectors are reported to be endemic in many countries across the world [ 4 , 5 , 6 ]. In 2018, globally, about 2.5 million cases of malaria were reported, wherein India alone accounted for 76% of the cases [ 7 ]. Several millions of humans die from mosquito-borne diseases every year, resulting in a drastic impact on socio-economic development [ 8 , 9 ].…”

In vitro anti-inflammatory, anti-arthritic and anti- proliferative activity of green synthesized silver nanoparticles - Phoenix dactylifera (Rothan dates)

“…The presence of peaks at 1619.3 and 1383.9 cm -1 region might be due to aromatic C=C stretching vibration. These peaks mainly belongs to the flavonoids and terpenoids in the plant extracts and is responsible for reduction of silver ions to silver nanoparticles by the plant extracts (Banerjee et al, 2014;Khader et al, 2018a), hence Rothan date seed extracts act as capping agent to produce silver nanoparticles. According to Haghighi Pak et al (2016) both FTIR spectra show a shift in peaks: 1401-1396 (due to C-C in-ring stretching of aromatic amines) and in this investigation the peak was observed at 1619.3 and 1383.9 cm -1 , it conforms the presence of aromatic amines.…”