Ovicidal and miracicidal activities of Calotropis procera and its green-synthesized nanotized derivative: A quest for new antifasciola agents.

Fascioliasis is an important zoonotic disease but treatment with the mainstay drugs poses challenge of parasite resistance. The aim of the study was to determine the anthelmintic efficacy of ethanolic leaf extract of Calotropis procera (CP) and its synthesized silver nanoparticles (AgNPs) against the eggs and miracidia of Fasciola species. The ethanolic extract of C. procera was used to synthesise its corresponding green-synthesis derivative using silver nitrate (CP-AgNPs). The synthesized silver nanoparticles were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy/Energy Dispersive X-ray (SEM/EDX). The ova and miracidia of Fasciola spp. were exposed to 1, 2, and 4 mg/ml CP ethanolic extracts and its corresponding AgNPs. FTIR showed that the formulation was capped with compounds present in the extract. The XRD showed the crystalline property of CP-AgNPs. The SEM image showed clusters of irregularly shape nanoparticles. The ovicidal activities were concentration dependent and showed highest activities 81.02±4.03% and 92.91±1.25% in 4 mg/ml CP and CP-AgNPs respectively (p < 0.05). The LC50 of CP (1.49 mg/ml) was more than 3 folds higher than that of CP-AgNPs (0.47 mg/ml). While CP did not cause miracidia death after 60 min exposure, however, 100% miracidia death were observed within 30 min exposure in all the tested concentration with CP-AgNPs. The positive control (ABZ) only showed 100% mortality after 60 min of exposure of miracidia. The study showed that green-synthesised C. procera nanoparticles showed superior ovicidal and miracicidal activities over C. procera leaf extracts and could be a source of potential antifasciola agent.

Okeke IJ ，Oyeyemi OT ，Morenikeji OA 《-》

Synthesis and antibacterial potential of Loranthus pulverulentus conjugated silver nanoparticles.

The green method is not only harmonious to our environment but saves time and is comparatively cheaper than other methods. The current study is aimed to synthesize the silver nanoparticles (AgNPs) using the green method by using the leaves of Loranthus pulverulentus Wall (LPW) which functioned as a reducing as well as capping agent. The synthesis of biogenic AgNPs was confirmed by UV-Vis spectroscopy (UV-Vis.), Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), and Fourier transform infrared (FTIR). The absorbance maxima of the synthesized AgNPs were observed in the range of 405-435 nm. The SEM was used to find out the size and shape of the synthesized AgNPs, which revealed that the NPs were rectangular having sizes from 05 to 16 nm. XRD revealed that the synthesized NPs were crystalline and face-centered cubic (FCC). EDX analysis reflected the elemental composition of the synthesized product and showed that the percentage of silver = 92. FTIR was used to confirm the functional groups responsible for the reduction and stabilization of silver ions. It revealed that biomolecules present in plant extract were responsible for the reduction and stabilization of silver ions. The effect of temperature, pH, reaction time, silver nitrate concentration, and plant extract concentration on the synthesis of AgNPs were also investigated. The synthesized silver nanoparticles were tested against four bacterial strains which showed strong antibacterial activity. We conclude that biogenic silver nanoparticles could be used as antibacterial agents to treat various diseases. RESEARCH HIGHLIGHTS: Loranthus pulverulentus Wall leaf extract mediated synthesis of silver nanoparticles. Effects of pH 3, 4, 6, 9, and 11, reaction time 5, 10, 20, 40 min, 1, 2, and 3 h, temperature 30, 40, 50, 60°C, silver nitrate concentration 0.5, 1.0, 2.0, and 3.0 mM and plant extract concentration 0.5, 1.0, 2.0, and 3.0 g on the AgNPs synthesis were also studied Scanning electron microscopy analysis revealed a small size of synthesized silver nanoparticles (8 nm). The synthesized silver nanoparticles were found effective against various bacterial pathogens.

Subhani MA ，Irshad M ，Nazir A ，Hafeez M ，Ali S ... -  《-》

Photo-induced and phytomediated synthesis of silver nanoparticles using Derris trifoliata leaf extract and its larvicidal activity against Aedes aegypti.

Due to the increased development of resistance of vectors against synthetic insecticides and chemical drugs, plant based insecticides serve as promising biocontrol agents for effective vector control. Green approach for the synthesis of nanoparticles has been attained using environmentally safe, non-toxic plant extracts. The present study was aimed to investigate the potent larvicidal activity of silver nanoparticles (AgNPs) produced by Derris trifoliata leaf extract in relation to the various concentrations of methanol and chloroform extracts for 24h against 3rd and 4th instar larvae of Aedes aegypti. AgNPs were synthesized using D. trifoliata leaf extract as reducing and stabilizing agent. Synthesized AgNPs were characterized by UV-Vis spectroscopy, FTIR spectroscopy, SEM, EDX, XRD and HRTEM. The size of AgNPs as estimated from the full width at half-maximum of (200) peak of silver was 16.13nm, the average crystalline size of the synthesized AgNPs was approximately 20nm, which was correlated with the HRTEM results (20nm). SEM and TEM images have shown the formation of polydispersed nanoparticles with an average size of 20nm. The FTIR spectra of AgNPs exhibited prominent peaks at 2360.7, 1606.2, 1095.6 and 785.9cm-1. The spectral peak observed at 1606.2, assigned to stretching vibration (C=O) in carbonyl compounds characterized by the presence of major constituents of flavonoids and terpenoids. The results obtained in FTIR spectroscopy correlated with the GC-MS analysis of methanol and chloroform extracts and indicates the presence of phytosteroids, flavonoids and terpenoids. The highest larvicidal activity was observed for the synthesized AgNPs against the 3rd instar larvae with LC50 values of 5.87mg/l and LC90 of 12.11mg/l, while against 4th instar larvae these values were7.00 and17.76mg/l respectively. The chloroform extracts also showed increased larvicidal activity than methanol extracts against 3rd instar larvae (LC50=54.42mg/l, LC90=140.83mg/l) and 4th instar larvae (LC50=62.47mg/l, LC90=145.06mg/l) of A. aegypti. Besides, the synthesized AgNPs also exhibited potent antibacterial activity against certain food borne pathogens. These results infer that the biologically synthesized AgNPs and organic solvent extracts have the potential to be used as an excellent eco-friendly approach for vector control against A. aegypti.

Kumar VA ，Ammani K ，Jobina R ，Subhaswaraj P ，Siddhardha B ... -  《-》

Calotropis procera (L.) mediated synthesis of AgNPs and their application to control leaf spot of Hibiscus rosa-sinensis (L.).

Nawab R ，Ali M ，Haroon U ，Kamal A ，Akbar M ，Anwar F ，Ahmed J ，Chaudhary HJ ，Iqbal A ，Hashem M ，Alamri S ，ALHaithloul HAS ，Munis MFH ... -  《-》

Optimizing antimicrobial synergy: Green synthesis of silver nanoparticles from Calotropis gigantea leaves enhanced by patchouli oil.

Kemala P ，Khairan K ，Ramli M ，Helwani Z ，Rusyana A ，Lubis VF ，Ahmad K ，Idroes GM ，Noviandy TR ，Idroes R ... -  《-》