The green fabrication of metal nanoparticles using botanical extracts is gaining increasing resea... more The green fabrication of metal nanoparticles using botanical extracts is gaining increasing research attention in nanotechnology, since it does not require high energy inputs or the production of highly toxic chemical byproducts. Here, silver (Ag), gold (Au) and their bimetallic (Ag/Au) nanoparticles (NPs) were green synthesized using the Gloriosa superba aqueous leaf extract. Metal NPs were studied by spectroscopic (UVevisible spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, XRD and EDX) and microscopic (AFM and TEM) analysis. AFM and TEM showed that Ag and Au NPs had triangular and spherical morphologies, with an average size of 20 nm. Bimetallic Ag/Au NPs showed spherical shapes with an average size of 10 nm. Ag and Ag/Au bimetallic NPs showed high antibacterial and antibiofilm activities towards Gram-positive and Gram-negative bacteria. Overall, the proposed synthesis route of Ag, Au and Ag/Au bimetallic NPs can be exploited by the pharmaceutical industry to develop drugs effective in the fight against microbic infections.
The aim of the present study was to synthesize CeO 2 nanoparticles using plant pathogenic fungus ... more The aim of the present study was to synthesize CeO 2 nanoparticles using plant pathogenic fungus F. solani and also to study the antibacterial activity as well as the influence on the inhibition of biofilm formation against the biomedically important bacterial 10 strains namely Staphylococcus aureus, Psedomonas aeriginosa, Escherichia coli and Klebsiella pneumoniae. Thermogravimetric/Differential thermal analysis (TG/DTA) suggested the crystallization temperature of as-synthesized CeO 2 nanopowder at 400 o C. Powder X-ray diffraction analysis and Raman spectroscopy substantiated the presence of CeO 2 nanoparticles with cubic fluorite structure. The contribution of functional groups corresponding to F. solani fungal supernatant for the synthesis of CeO 2 nanoparticles was studied by Fourier transform infrared (FTIR) spectroscopy. Room temperature photoluminescence spectrum of 15 calcined CeO 2 nanopowder was recorded. Field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray spectroscopy (EDAX) ascertained the formation of homogeneously distributed spherical shaped CeO 2 nanoparticles. Furthermore, Transmission electron microscopy (TEM) demonstrated the spherical morphology of the CeO 2 nanoparticles having the size ranging from 20 to 30 nm and also selected area electron diffraction (SAED) pattern revealed the polycrystalline nature of CeO 2 nanoparticles, which is consistent with the XRD results. The presence of surface oxidation states Ce (3d) and O (1s) of CeO 2 nanoparticles was 20 confirmed by X-ray Phoelectron Spectroscopy (XPS) analysis. Antibacterial activity of CeO 2 nanoparticles was evaluated by disc diffusion method and it showed highest activity against P. aeruginosa as well as K. pneumoniae. In addition, the inhibition on biofilm formation by CeO 2 nanoparticles has also been examined by confocal laser scanning microscopy (CLSM). Furthermore, the electrochemical property of biosynthesized CeO 2 nanoparticles was studied by cyclic voltammetry technique. 25
Sucrose is a major commodity in worldwide. In half a century the progress towards the understandi... more Sucrose is a major commodity in worldwide. In half a century the progress towards the understanding of the chemistry, structure, physical and functional properties of the sucrose molecule have been rapid. It was crystallized from the hot methanol extract of the rhizome powder of Gloriosa superba by using slow evaporation method at room temperature. The synthesized sucrose crystal lattice parameters were characterized by single crystal X-ray diffraction analysis. The presences of organic functional groups in the grown crystal were identified by FT-IR and Micro Raman analyses. The optical parameter of the grown single crystal was analyzed by UV-visible spectroscopy and maximum absorption was occurred at 253 nm. In addition, HOMO, LUMO, Molecular Electrostatic Potential (MESP), non-linear optical and several thermodynamic properties were analyzed by the DFT calculations. The thermal degradation of the sucrose crystal was tested by Thermo Gravimetric/Differential Thermal Analysis (TG/DTA).
Cerium oxide nanoparticles (CeO2 NPs) were
synthesized using Aspergillus niger culture filtrate. ... more Cerium oxide nanoparticles (CeO2 NPs) were synthesized using Aspergillus niger culture filtrate. The mycosynthesized CeO2 NPs were characterized by UV– Visible (UV–Vis), Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), Micro Raman, Thermogravi- metric/Differential Thermal Analysis (TG/DTA), Photo- luminescence, and Transmission Electron Microscopy (TEM) analyses. UV–Vis spectrum exhibited a corre- sponding absorption peak for CeO2 NPs at 296 nm, and the functional groups present in the fungal filtrate responsible for the synthesis of NPs were analyzed by FT-IR. The further characterization of the mycosynthe- sized CeO2 NPs revealed particles of the cubic structure and spherical shape, with the particle sizes ranging from 5 to 20 nm. The antibacterial activity of CeO2 NPs was examined in respect of two Gram-positive (G?) bacteria (Streptococcus pneumoniae, Bacillus subtilis) and two Gram-negative (G-) bacteria (Proteus vulgaris, Escher- ichia coli) by disk diffusion method. The test results for CeO2 NPs at a concentration of 10 mg/mL showed higher activities on the zone of inhibition of up to 10.67 ± 0.33 and 10.33 ± 0.33 mm against Streptococ- cus pneumonia and Bacillus subtilis, respectively, The CeO2 NPs caused 100 % mortality on first instar of Aedes aegypti at 0.250 mg/L concentration after 24-h exposure. The mycosynthesis of CeO2 NPs is a simple, cost-effective and eco-friendly approach and it will also potentially helpful to control pathogenic bacteria and dengue vector.
CeO2 nanoparticles (NPs) were green synthesized using Gloriosa superba L. leaf extract. The synth... more CeO2 nanoparticles (NPs) were green synthesized using Gloriosa superba L. leaf extract. The synthesized nanopar- ticles retained the cubic structure, which was confirmed by X-ray diffraction studies. The oxidation states of the elements (C (1s), O (1s) and Ce (3d)) were confirmed by XPS studies. TEM images showed that the NPs possessed spherical shape and particle size of 5 nm. The Ce–O stretching bands were observed at 451 cm−1 and 457 cm−1 from the FT-IR and Raman spectra respectively. The band gap of the CeO2 NPs was estimated as 3.78 eV from the UV–visible spectrum. From the photoluminescence measurements, the broad emission composed of eight dif- ferent bands were found. The antibacterial studies performed against a set of bacterial strains showed that Gram positive (G+) bacteria were relatively more susceptible to the NPs than Gram negative (G−) bacteria. The toxicological behavior of CeO2 NPs was found due to the synthesized NPs with uneven ridges and oxygen defects in CeO2 NPs.
The green fabrication of metal nanoparticles using botanical extracts is gaining increasing resea... more The green fabrication of metal nanoparticles using botanical extracts is gaining increasing research attention in nanotechnology, since it does not require high energy inputs or the production of highly toxic chemical byproducts. Here, silver (Ag), gold (Au) and their bimetallic (Ag/Au) nanoparticles (NPs) were green synthesized using the Gloriosa superba aqueous leaf extract. Metal NPs were studied by spectroscopic (UVevisible spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, XRD and EDX) and microscopic (AFM and TEM) analysis. AFM and TEM showed that Ag and Au NPs had triangular and spherical morphologies, with an average size of 20 nm. Bimetallic Ag/Au NPs showed spherical shapes with an average size of 10 nm. Ag and Ag/Au bimetallic NPs showed high antibacterial and antibiofilm activities towards Gram-positive and Gram-negative bacteria. Overall, the proposed synthesis route of Ag, Au and Ag/Au bimetallic NPs can be exploited by the pharmaceutical industry to develop drugs effective in the fight against microbic infections.
The aim of the present study was to synthesize CeO 2 nanoparticles using plant pathogenic fungus ... more The aim of the present study was to synthesize CeO 2 nanoparticles using plant pathogenic fungus F. solani and also to study the antibacterial activity as well as the influence on the inhibition of biofilm formation against the biomedically important bacterial 10 strains namely Staphylococcus aureus, Psedomonas aeriginosa, Escherichia coli and Klebsiella pneumoniae. Thermogravimetric/Differential thermal analysis (TG/DTA) suggested the crystallization temperature of as-synthesized CeO 2 nanopowder at 400 o C. Powder X-ray diffraction analysis and Raman spectroscopy substantiated the presence of CeO 2 nanoparticles with cubic fluorite structure. The contribution of functional groups corresponding to F. solani fungal supernatant for the synthesis of CeO 2 nanoparticles was studied by Fourier transform infrared (FTIR) spectroscopy. Room temperature photoluminescence spectrum of 15 calcined CeO 2 nanopowder was recorded. Field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray spectroscopy (EDAX) ascertained the formation of homogeneously distributed spherical shaped CeO 2 nanoparticles. Furthermore, Transmission electron microscopy (TEM) demonstrated the spherical morphology of the CeO 2 nanoparticles having the size ranging from 20 to 30 nm and also selected area electron diffraction (SAED) pattern revealed the polycrystalline nature of CeO 2 nanoparticles, which is consistent with the XRD results. The presence of surface oxidation states Ce (3d) and O (1s) of CeO 2 nanoparticles was 20 confirmed by X-ray Phoelectron Spectroscopy (XPS) analysis. Antibacterial activity of CeO 2 nanoparticles was evaluated by disc diffusion method and it showed highest activity against P. aeruginosa as well as K. pneumoniae. In addition, the inhibition on biofilm formation by CeO 2 nanoparticles has also been examined by confocal laser scanning microscopy (CLSM). Furthermore, the electrochemical property of biosynthesized CeO 2 nanoparticles was studied by cyclic voltammetry technique. 25
Sucrose is a major commodity in worldwide. In half a century the progress towards the understandi... more Sucrose is a major commodity in worldwide. In half a century the progress towards the understanding of the chemistry, structure, physical and functional properties of the sucrose molecule have been rapid. It was crystallized from the hot methanol extract of the rhizome powder of Gloriosa superba by using slow evaporation method at room temperature. The synthesized sucrose crystal lattice parameters were characterized by single crystal X-ray diffraction analysis. The presences of organic functional groups in the grown crystal were identified by FT-IR and Micro Raman analyses. The optical parameter of the grown single crystal was analyzed by UV-visible spectroscopy and maximum absorption was occurred at 253 nm. In addition, HOMO, LUMO, Molecular Electrostatic Potential (MESP), non-linear optical and several thermodynamic properties were analyzed by the DFT calculations. The thermal degradation of the sucrose crystal was tested by Thermo Gravimetric/Differential Thermal Analysis (TG/DTA).
Cerium oxide nanoparticles (CeO2 NPs) were
synthesized using Aspergillus niger culture filtrate. ... more Cerium oxide nanoparticles (CeO2 NPs) were synthesized using Aspergillus niger culture filtrate. The mycosynthesized CeO2 NPs were characterized by UV– Visible (UV–Vis), Fourier Transform Infrared (FT-IR), X-ray diffraction (XRD), Micro Raman, Thermogravi- metric/Differential Thermal Analysis (TG/DTA), Photo- luminescence, and Transmission Electron Microscopy (TEM) analyses. UV–Vis spectrum exhibited a corre- sponding absorption peak for CeO2 NPs at 296 nm, and the functional groups present in the fungal filtrate responsible for the synthesis of NPs were analyzed by FT-IR. The further characterization of the mycosynthe- sized CeO2 NPs revealed particles of the cubic structure and spherical shape, with the particle sizes ranging from 5 to 20 nm. The antibacterial activity of CeO2 NPs was examined in respect of two Gram-positive (G?) bacteria (Streptococcus pneumoniae, Bacillus subtilis) and two Gram-negative (G-) bacteria (Proteus vulgaris, Escher- ichia coli) by disk diffusion method. The test results for CeO2 NPs at a concentration of 10 mg/mL showed higher activities on the zone of inhibition of up to 10.67 ± 0.33 and 10.33 ± 0.33 mm against Streptococ- cus pneumonia and Bacillus subtilis, respectively, The CeO2 NPs caused 100 % mortality on first instar of Aedes aegypti at 0.250 mg/L concentration after 24-h exposure. The mycosynthesis of CeO2 NPs is a simple, cost-effective and eco-friendly approach and it will also potentially helpful to control pathogenic bacteria and dengue vector.
CeO2 nanoparticles (NPs) were green synthesized using Gloriosa superba L. leaf extract. The synth... more CeO2 nanoparticles (NPs) were green synthesized using Gloriosa superba L. leaf extract. The synthesized nanopar- ticles retained the cubic structure, which was confirmed by X-ray diffraction studies. The oxidation states of the elements (C (1s), O (1s) and Ce (3d)) were confirmed by XPS studies. TEM images showed that the NPs possessed spherical shape and particle size of 5 nm. The Ce–O stretching bands were observed at 451 cm−1 and 457 cm−1 from the FT-IR and Raman spectra respectively. The band gap of the CeO2 NPs was estimated as 3.78 eV from the UV–visible spectrum. From the photoluminescence measurements, the broad emission composed of eight dif- ferent bands were found. The antibacterial studies performed against a set of bacterial strains showed that Gram positive (G+) bacteria were relatively more susceptible to the NPs than Gram negative (G−) bacteria. The toxicological behavior of CeO2 NPs was found due to the synthesized NPs with uneven ridges and oxygen defects in CeO2 NPs.
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of Gloriosa superba by using slow evaporation method at room temperature. The synthesized sucrose crystal lattice parameters were characterized by single crystal X-ray diffraction analysis. The presences of organic functional groups in the grown crystal were identified by FT-IR and Micro Raman analyses. The optical parameter of the grown single crystal was analyzed by UV-visible spectroscopy and maximum absorption was occurred at 253 nm. In addition, HOMO, LUMO, Molecular Electrostatic Potential (MESP), non-linear optical and several thermodynamic properties
were analyzed by the DFT calculations. The thermal degradation of the sucrose crystal was tested by Thermo Gravimetric/Differential Thermal Analysis (TG/DTA).
synthesized using Aspergillus niger culture filtrate. The
mycosynthesized CeO2 NPs were characterized by UV–
Visible (UV–Vis), Fourier Transform Infrared (FT-IR),
X-ray diffraction (XRD), Micro Raman, Thermogravi-
metric/Differential Thermal Analysis (TG/DTA), Photo-
luminescence, and Transmission Electron Microscopy
(TEM) analyses. UV–Vis spectrum exhibited a corre-
sponding absorption peak for CeO2 NPs at 296 nm, and
the functional groups present in the fungal filtrate
responsible for the synthesis of NPs were analyzed by
FT-IR. The further characterization of the mycosynthe-
sized CeO2 NPs revealed particles of the cubic structure
and spherical shape, with the particle sizes ranging from
5 to 20 nm. The antibacterial activity of CeO2 NPs was
examined in respect of two Gram-positive (G?) bacteria
(Streptococcus pneumoniae, Bacillus subtilis) and two
Gram-negative (G-) bacteria (Proteus vulgaris, Escher-
ichia coli) by disk diffusion method. The test results for
CeO2 NPs at a concentration of 10 mg/mL showed
higher activities on the zone of inhibition of up to
10.67 ± 0.33 and 10.33 ± 0.33 mm against Streptococ-
cus pneumonia and Bacillus subtilis, respectively, The
CeO2 NPs caused 100 % mortality on first instar of
Aedes aegypti at 0.250 mg/L concentration after 24-h exposure. The mycosynthesis of CeO2 NPs is a simple,
cost-effective and eco-friendly approach and it will also
potentially helpful to control pathogenic bacteria and
dengue vector.
ticles retained the cubic structure, which was confirmed by X-ray diffraction studies. The oxidation states of the
elements (C (1s), O (1s) and Ce (3d)) were confirmed by XPS studies. TEM images showed that the NPs possessed
spherical shape and particle size of 5 nm. The Ce–O stretching bands were observed at 451 cm−1 and 457 cm−1
from the FT-IR and Raman spectra respectively. The band gap of the CeO2 NPs was estimated as 3.78 eV from the
UV–visible spectrum. From the photoluminescence measurements, the broad emission composed of eight dif-
ferent bands were found. The antibacterial studies performed against a set of bacterial strains showed that
Gram positive (G+) bacteria were relatively more susceptible to the NPs than Gram negative (G−) bacteria.
The toxicological behavior of CeO2 NPs was found due to the synthesized NPs with uneven ridges and oxygen
defects in CeO2 NPs.
of Gloriosa superba by using slow evaporation method at room temperature. The synthesized sucrose crystal lattice parameters were characterized by single crystal X-ray diffraction analysis. The presences of organic functional groups in the grown crystal were identified by FT-IR and Micro Raman analyses. The optical parameter of the grown single crystal was analyzed by UV-visible spectroscopy and maximum absorption was occurred at 253 nm. In addition, HOMO, LUMO, Molecular Electrostatic Potential (MESP), non-linear optical and several thermodynamic properties
were analyzed by the DFT calculations. The thermal degradation of the sucrose crystal was tested by Thermo Gravimetric/Differential Thermal Analysis (TG/DTA).
synthesized using Aspergillus niger culture filtrate. The
mycosynthesized CeO2 NPs were characterized by UV–
Visible (UV–Vis), Fourier Transform Infrared (FT-IR),
X-ray diffraction (XRD), Micro Raman, Thermogravi-
metric/Differential Thermal Analysis (TG/DTA), Photo-
luminescence, and Transmission Electron Microscopy
(TEM) analyses. UV–Vis spectrum exhibited a corre-
sponding absorption peak for CeO2 NPs at 296 nm, and
the functional groups present in the fungal filtrate
responsible for the synthesis of NPs were analyzed by
FT-IR. The further characterization of the mycosynthe-
sized CeO2 NPs revealed particles of the cubic structure
and spherical shape, with the particle sizes ranging from
5 to 20 nm. The antibacterial activity of CeO2 NPs was
examined in respect of two Gram-positive (G?) bacteria
(Streptococcus pneumoniae, Bacillus subtilis) and two
Gram-negative (G-) bacteria (Proteus vulgaris, Escher-
ichia coli) by disk diffusion method. The test results for
CeO2 NPs at a concentration of 10 mg/mL showed
higher activities on the zone of inhibition of up to
10.67 ± 0.33 and 10.33 ± 0.33 mm against Streptococ-
cus pneumonia and Bacillus subtilis, respectively, The
CeO2 NPs caused 100 % mortality on first instar of
Aedes aegypti at 0.250 mg/L concentration after 24-h exposure. The mycosynthesis of CeO2 NPs is a simple,
cost-effective and eco-friendly approach and it will also
potentially helpful to control pathogenic bacteria and
dengue vector.
ticles retained the cubic structure, which was confirmed by X-ray diffraction studies. The oxidation states of the
elements (C (1s), O (1s) and Ce (3d)) were confirmed by XPS studies. TEM images showed that the NPs possessed
spherical shape and particle size of 5 nm. The Ce–O stretching bands were observed at 451 cm−1 and 457 cm−1
from the FT-IR and Raman spectra respectively. The band gap of the CeO2 NPs was estimated as 3.78 eV from the
UV–visible spectrum. From the photoluminescence measurements, the broad emission composed of eight dif-
ferent bands were found. The antibacterial studies performed against a set of bacterial strains showed that
Gram positive (G+) bacteria were relatively more susceptible to the NPs than Gram negative (G−) bacteria.
The toxicological behavior of CeO2 NPs was found due to the synthesized NPs with uneven ridges and oxygen
defects in CeO2 NPs.