Manisha Bawskar; Sunita Bansod; Dnyaneshwar Rathod; Carolina Alves dos Santos; Pramod Ingle; Mahendra Rai; Aniket Gade
Abstract
Fungal infections are major issue in agricultural crop plants that affects the growth of plant causing huge economic losses. Silver nanoparticles (AgNPs) have shown antimicrobial effects. Here, we report the potential application of phytostabilized AgNPs as a novel nanofungicide and growth promoter in ...
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Fungal infections are major issue in agricultural crop plants that affects the growth of plant causing huge economic losses. Silver nanoparticles (AgNPs) have shown antimicrobial effects. Here, we report the potential application of phytostabilized AgNPs as a novel nanofungicide and growth promoter in Vigna radiata (L.) R. Wilczek (Mung). The aqueous extract of Azadirachta indica (Neem) challenged with AgNO3 (1mM) develops a brown colour, indicating AgNPs synthesis. Detection of AgNPs was monitored by UV-Vis spectroscopy, which showed peak at 415 nm. Further confirmation was done by Fourier Transform Infra-Red Spectroscopy which illustrates functional groups present in the capping proteins. Nanoparticle Tracking Analysis, and Transmission Electron Microscopy confirmed the synthesis of spherical, polydispersed nanoparticles in the range of 15-35 nm. AgNPs proved to exhibit antifungal potential in suppression of fungal plant pathogens. Seed germination percentage was much higher for the AgNPs treated seeds as compared to control. Handy-PEA analyzer (measures chl-a fluorescence) indicating seedlings inoculated with AgNPs were grown as the healthy plant with greater vitality, compared to control plants. Phytostabilized AgNPs were found to be biocompatible and have a promising attribute in developing a potent nanofungicide to enhance productivity rate and prevent fungal infections in crops with no potential toxicity.
Harsha Pinjarkar; Swapnil Gaikwad; Avinash P. Ingle; Aniket Gade; Mahendra Rai
Abstract
In the present study, the extracellular phycofabrication (synthesis by algae) of silver nanoparticles was demonstrated using algae i.e. Spirogyra sp. recovered from the fresh water. The reduction of silver ions present in the aqueous solution of silver sulphate (Ag2SO4) was done by the cell filtrate ...
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In the present study, the extracellular phycofabrication (synthesis by algae) of silver nanoparticles was demonstrated using algae i.e. Spirogyra sp. recovered from the fresh water. The reduction of silver ions present in the aqueous solution of silver sulphate (Ag2SO4) was done by the cell filtrate of Spirogyra sp. leading to the synthesis of silver nanoparticles. Phycofabrication of silver nanoparticles was confirmed by using characterization tools like UV-Vis spectrophotometer, FTIR, TEM and NTA. The resulting silver nanoparticles were spherical in shape, in the range of 40-80 nm and capped with proteins. Through the experimental studies, it was found that temperature, pH and salt concentration affects the rate of phycofabrication of silver nanoparticles. Antibacterial study of phycofabricated silver nanoparticles was assessed against human pathogenic bacteria. These silver nanoparticles showed better antibacterial activity against gram positive bacteria i.e. Staphylococcus aureus (ATCC-25923) (13 mm) as compared to Gram negative bacteria i.e. Escherichia coli JM-103 (ATCC-39403) (11 mm). This is the first report of synthesis of silver nanoparticles by Spirogyra sp < /em>. using Ag2SO4 as a salt. Extracellular phycofabrication of silver nanoparticles by Spirogyra sp. was found be easy, simple and eco-friendly method.
Dipali Nagaonkar; Mahendra Rai
Abstract
Bimetallic nanoparticles have emerged up as advanced nanomaterials due to the synergism between two metallic nanoparticles in core-shell or alloy arrangement. Moreover, bioinspired synthesis of nanoparticles is an evergreen approach of nanobiosciences. In this experiment, we have fabricated silver, gold ...
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Bimetallic nanoparticles have emerged up as advanced nanomaterials due to the synergism between two metallic nanoparticles in core-shell or alloy arrangement. Moreover, bioinspired synthesis of nanoparticles is an evergreen approach of nanobiosciences. In this experiment, we have fabricated silver, gold and silver (core) - gold (shell) bimetallic nanoparticles using leaf extract of Catharanthus roseus Linn. by sequential reduction technique. The sequentially reduced silver-gold nanoparticles in core-shell arrangement were detected by shift in the surface plasmon resonance of nanoparticles from 423 nm to 526 nm with the aid of UV-Visible spectrophotometer. Nanoparticle tracking analysis confirmed the mean particle size for all the nanoparticles within the range 11 to 65 nm. X-Ray diffraction analysis revealed Bragg’s reflections denoting face cubic centered crystalline nature of all the synthesized nanoparticles. Transmission electron microscopy showed that silver and silver-gold nanoparticles are quite polydispersed and spherical in shape while anisotropic Au nanoparticles were also observed. These phytofabricated Ag-Au nanoparticles have been evaluated with enhanced antibacterial and anticandidal potential over their monometallic counterparts with particular reference to some pathogenic bacteria and Candida sp. The maximum lethality of bimetallic nanoparticles was observed for Escherichia coli followed by Pseudomonas aeruginosa, while Candida parapsilosis was found to be the least susceptible organism for the silver-gold nanoparticles.
