scholarly journals Biogenic silver nanoparticles from Trichodesma indicum aqueous leaf extract against Mythimna separata and evaluation of its larvicidal efficacy

2017 ◽  
Vol 57 (2) ◽  
pp. 194-200 ◽  
Author(s):  
Abdul A. Buhroo ◽  
Gousul Nisa ◽  
Syed Asrafuzzaman ◽  
Ram Prasad ◽  
Razia Rasheed ◽  
...  

AbstractThe present exploration is focused on the bio-fabrication of silver nanoparticles (Ag NPs) usingTrichodesma indicumaqueous leaf extract as a reducing agent. The synthesized Ag NPs were productively characterized by UV-vis spectroscopy, XRD, and TEM studies. The photosynthesis of Ag NPs was done at room temperature for 24 h and at 60°C. The green synthesis of spherical-shaped Ag NPs bio-fabricated fromT. indicumwith a face centred cubic structure showed average particle sizes of 20–50 nm, which is inconsistent with the particle size calculated by the XRD Scherer equation and TEM analysis. We further explored the larvicidal efficacy of biosynthesized Ag NPs with leaf extracts ofT. indicumagainstMythimna separata. The results showed that Ag NPs (20–50 nm) ofT. indicumpossess good larvicidal activity againstM. separatawith an LC50of 500 ppm. Thus, we can advocate that Ag NPs of 20–50 nm size extracted fromT. indicummay be considered in the pest management programme ofM. separatain future.

2020 ◽  
Vol 9 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Samaira Yasmin ◽  
Shazia Nouren ◽  
Haq Nawaz Bhatti ◽  
Dure Najaf Iqbal ◽  
Shan Iftikhar ◽  
...  

AbstractCurrently, the green route for synthesis of silver nanoparticles (Ag NPs) using plants leaf extract is an emerging research area in nanotechnology. The present study was explored for synthesis, characterization and catalytic application of Ag NPs using Diospyros lotus fresh leaf extracts. Factors affecting the synthesis were optimized and optimum conditions were pH of 8.6, silver nitrate (AgNO3) concentration of 1.5 mM and 10 mL leaf extract. Formation of Ag NPs was observed by change in color of reaction mixture from pale yellow to reddish brown. The synthesized Ag NPs were characterized using UV-Vis spectrophotometer, EDX, XRD and SEM analyses. UV-Vis spectrophotometer showed maximum absorbance peak in the range of 407 nm at different time intervals indicating formation of Ag NPs. SEM and XRD analysis confirmed face centered cubic structure and crystalline nature of biologically synthesized Ag NPs with average particle size of 27 nm. The purity of synthesized Ag NPs was revealed by EDX. Finally, photo catalytic activity (PCA) of Ag NPs was studied and 72.91% decolorization of industrial waste water was obtained at 54 h. Some important parameters like pH, turbidity, conductance; TSS, TDS, sulphide, sulphates, etc. were also monitored before and after treatment with Ag NPs.


2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110121
Author(s):  
Kashan Khan ◽  
Saleem Javed

A wide variety of methods have synthesized silver nanoparticles (Ag-NPs) in the recent past; however, biological methods have attracted much attention over the traditional chemical synthesis method due to being non-hazardous and eco-friendly. Here, a detailed and systemic study was performed to compare two different synthesis routes for Ag-NPs, that is, the chemical and the biological; their possible outcomes have also been described. Ag-NPs were synthesized chemically (cAg-NPs) using a chemical reductant and biologically (bAg-NPs) by using aqueous leaf extract of Azadirachta indica (neem). The synthesized nanoparticles were characterized using UV-visible spectrophotometry, FT-IR, EDX, and TEM. The average particle sizes (APS) of cAg-NPs were found to be 8 and 13 nm and of bAg-NPs to be 19 and 43 nm under different AgNO3 concentrations. The antimicrobial tests of differently sized NPs were performed against Escherichia coli (Gram −ve) and S taphylococcus aureus (Gram +ve). The results revealed that bAg-NPs of APS 43 nm were highly antimicrobial against both the tested bacterial stains followed by cAg-NPs of 8 nm. We found the effect of cAg-NPs to be size-dependent, whereas bAg-NPs showed a more significant antimicrobial effect than cAg-NPs.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Akshay Rajeev Geetha ◽  
Elizabeth George ◽  
Akshay Srinivasan ◽  
Jameel Shaik

Production of silver nanoparticles from the leaf extracts ofPimenta dioicais reported for the first time in this paper. Three different sets of leaves were utilized for the synthesis of nanoparticles—fresh, hot-air oven dried, and sun-dried. These nanoparticles were characterized using UV-Vis spectroscopy and AFM. The results were diverse in that different sizes were seen for different leaf conditions. Nanoparticles synthesized using sun-dried leaves (produced using a particular ratio (1 : 0.5) of the leaf extract sample and silver nitrate (1 mM), resp.) possessed the smallest sizes. We believe that further optimization of the current green-synthesis method would help in the production of monodispersed silver nanoparticles having great potential in treating several diseases.


Antibiotics ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 68 ◽  
Author(s):  
Mahsa Eshghi ◽  
Hamideh Vaghari ◽  
Yahya Najian ◽  
Mohammad Najian ◽  
Hoda Jafarizadeh-Malmiri ◽  
...  

Silver nanoparticles (Ag NPs) were synthesized using Juglans regia (J. regia) leaf extract, as both reducing and stabilizing agents through microwave irradiation method. The effects of a 1% (w/v) amount of leaf extract (0.1–0.9 mL) and an amount of 1 mM AgNO3 solution (15–25 mL) on the broad emission peak (λmax) and concentration of the synthesized Ag NPs solution were investigated using response surface methodology (RSM). Fourier transform infrared analysis indicated the main functional groups existing in the J. regia leaf extract. Dynamic light scattering, UV-Vis spectroscopy and transmission electron microscopy were used to characterize the synthesized Ag NPs. Fabricated Ag NPs with the mean particle size and polydispersity index and maximum concentration and zeta potential of 168 nm, 0.419, 135.16 ppm and −15.6 mV, respectively, were obtained using 0.1 mL of J. regia leaf extract and 15 mL of AgNO3. The antibacterial activity of the fabricated Ag NPs was assessed against both Gram negative (Escherichia coli) and positive (Staphylococcus aureus) bacteria and was found to possess high bactericidal effects.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Melisa A. Quinteros ◽  
Ivana M. Aiassa Martínez ◽  
Pablo R. Dalmasso ◽  
Paulina L. Páez

Currently, the biosynthesis of silver-based nanomaterials attracts enormous attention owing to the documented antimicrobial properties of these ones. This study reports the extracellular biosynthesis of silver nanoparticles (Ag-NPs) using aPseudomonas aeruginosastrain from a reference culture collection. A greenish culture supernatant ofP. aeruginosaincubated at 37°C with a silver nitrate solution for 24 h changed to a yellowish brown color, indicating the formation of Ag-NPs, which was confirmed by UV-vis spectroscopy, transmission electron microscopy, and X-ray diffraction. TEM analysis showed spherical and pseudospherical nanoparticles with a distributed size mainly between 25 and 45 nm, and the XRD pattern revealed the crystalline nature of Ag-NPs. Also it provides an evaluation of the antimicrobial activity of the biosynthesized Ag-NPs against human pathogenic and opportunistic microorganisms, namely,Staphylococcus aureus,Staphylococcus epidermidis,Enterococcus faecalis,Proteus mirabilis,Acinetobacter baumannii,Escherichia coli,P. aeruginosa, andKlebsiella pneumonia. Ag-NPs were found to be bioactive at picomolar concentration levels showing bactericidal effects against both Gram-positive and Gram-negative bacterial strains. This work demonstrates the first helpful use of biosynthesized Ag-NPs as broad spectrum bactericidal agents for clinical strains of pathogenic multidrug-resistant bacteria such as methicillin-resistantS. aureus,A. baumannii, andE. coli. In addition, these Ag-NPs showed negligible cytotoxic effect in human neutrophils suggesting low toxicity to the host.


2021 ◽  
Vol 34 (1) ◽  
pp. 216-222
Author(s):  
Arnannit Kuyyogsuy ◽  
Paweena Porrawatkul ◽  
Rungnapa Pimsen ◽  
Prawit Nuengmatcha ◽  
Benjawan Ninwong ◽  
...  

Silver nanoparticles were synthesized by bioreduction of silver nitrate using the aqueous leaf extract of Combretum indicum (CI-AgNPs). The synthesized CI-AgNPs exhibited a distinct absorption peak at 414 nm in UV-vis spectroscopy. Various parameters such as pH, temperature and time were optimized using spectrophotometry. The particle size of the CI-AgNPs was 48 nm as evaluated from the laser particle size analyzer. The XRD and EDX analyses confirmed the presence of silver in silver nanoparticles. Synthesized CI-AgNPs revealed significant antioxidant, antimicrobial (against Escherichia coli and Staphylococcus aureus) and photocatalytic (against methylene blue under sunlight irradiation) activities. Thus, an eco-friendly method was developed to synthesize silver nanoparticles using the C. indicum leaf extract.


Author(s):  
Shyamal K. Jash ◽  
Dilip Gorai ◽  
Arindam Gangopadhyay

The field of nanotechnology and nanoscience is the most currently an area of intense scientific interest for researchers in modern materials science. However there are many chemical as well as physical methods, green synthesis of nanomaterials is the most emerging method of synthesis. We report the synthesis of antibacterial silver nanoparticles (AgNPs) using aqueous leaf extract of medicinal herb Synedrella nodiflora (L.) Gaertn (Family: Asteraceae) at direct sunlight and monitored by UV-Vis spectroscopy. Both leaf extract and resulting AgNPs is subjected to antibacterial study against five pathogenic bacterial strains such as Bacillus megaterium, Staphylococcus aureus, Listeria monocytogenes, Pseudomonas aeruginosa and Salmonella typhimurium. AgNPs exhibited higher antibacterial efficacy than leaf extract and found to be more effective against                              B.  megaterium and  S. aureus.  


Biomedicine ◽  
2020 ◽  
Vol 39 (4) ◽  
pp. 544-549
Author(s):  
G. K. Pratap ◽  
Manjula Shantaram

Introduction and Aim: The silver nanoparticles have attained a special place in the area of nanotechnology because of their different biological applications. Fabrication of nanoparticles using green synthesis is  done because of its wide applications in different fields such as biomedical, medicine, agriculture and food engineering. This study is to develop an easy and eco-friendly method for the synthesis of Ag-NPs using leaf extracts of the medicinal plant. Materials and Methods: The medicinal plants are rich sources of various medicinal properties. Olea dioica Roxb., leaf extract was used to investigate the effects of Ag-NPs having antibacterial activity and antioxidant capacity.  The plant leaf extract contains flavonoids, alkaloids, saponins, and phenolic compounds which acts as reducing and stabilizing agents. The green synthesized silver nanoparticles were characterized by various techniques like UV- visible spectrophotometer, FTIR spectroscopy, and SEM analysis. Results: The synthesis of sliver nanoparticles from plant source, and analysis of nano particles by UV-Vis spectra, SEM and FTIR. The biological evaluations of Ag-NPs indicated an excellent inhibitory efficacy, antioxidant and antimicrobial activity for their future applications in medicine. Conclusion: The synthesized silver nanoparticles exhibited potent antioxidant and antimicrobial activities against Gram-positive and Gram-negative bacteria. The silver (Ag-NPs) nanoparticles synthesized by the pot green synthesis method proves its potential use in various medical applications. Keywords: Silver nanoparticles; Medicinal plants; Ag-NPs; Olea dioica Roxb.,


2021 ◽  
Vol 3 (1) ◽  
pp. 76-81
Author(s):  
Siti Husnaa Mohd Taib ◽  
Kamyar Shameli ◽  
Roshafima Rasit Ali ◽  
Zahra Izadiyan ◽  
Zatil Izzah Ahmad Tarmizi

The present paper reports the synthesis of silver nanoparticles (Ag-NPs) by a green method using Hibiscus sabdariffa (H. sabdariffa) leaves extract as reductant and stabilizer. The synthesized Ag-NPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). UV-vis spectrum of synthesized Ag-NPs showed a peak at 378 nm. TEM analysis revealed that the particles were spherical and irregular in shape and has average size around 56.52 nm. This structure and size of particles were confirmed by AFM analysis. The UV-vis and FTIR spectrum provides evidence of the presence of caffeic acid component as a representative biomolecule in stabilising the nanoparticles based on previous studies. Hence, this study advocates that H. sabdariffa have potential for synthesizing nanoparticles.


2020 ◽  
Vol 1 (1) ◽  
pp. 10-17
Author(s):  
Selvam K.A ◽  
◽  
Suriyakumar M ◽  
Devanathan J ◽  
Kolanjinathan K ◽  
...  

Medicines of plant origin have been used to combat human diseases since time immemorial even before the history of their documentation. They have been used by human beings since time immemorial for curing health. The phytochemical screening of leaf extracts of Persea americanashows the presence of alkaloids, flavanoids, carbohydrates, saponins, protein, tannins and glycoside. Also the synthesis of silver nanoparticles was done using ethanolic Persea americana leaf extract. The synthesized silver nanoparticles were characterized by using Ultraviolet- visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) analysis. The antimicrobial potential of synthesized nanoparticles was determined on the basis of mean diameter of zone of inhibition around the disc in millimeters. The antibacterial activity was evaluated qualitatively through agar disc diffusion towards Lactobacillus sp, Staphylococcus aureus, Streptococcus mutans, Klebsiella pneumoniae, Serratia marcescens, and Escherichia coli. The highest zone of inhibition value (15.0 mm) in Streptococcus mutans 15 ± 0.6. The antifungal activity against Aspergillus niger, Aspergillus flaves ,Candida albicans and Fusarium sp. From the results, excellent and eco-friendly green source for production of potential bio antimicrobial silver nanoparticles.


Sign in / Sign up

Export Citation Format

Share Document