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Green Synthesis and characterization of Silver nanoparticles from Cajanus cajanleaf extract and its antibacterial activity

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Veerababu Nagati at University of Hyderabad
Veerababu Nagati
Rama Koyyati at Osmania University
Rama Koyyati
Manisha R Donda
Manisha R Donda
Manisha R Donda
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Jahnavi Alwala at Osmania University
Jahnavi Alwala
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Abstract and Figures

Nanoparticles, because of their diversified applications in the field of modern medicine are an important thrust area. So, in the present investigation synthesis and characterization of Silver nanoparticles (AgNPs), and their antimicrobial effect on bacteria were studied. By using leaf extracts of Cajanus cajan (pigeon pea), AgNPs were prepared by green synthesis process from 1mM AgNO 3 solution. The color change observed after the addition of AgNO3 was due to the surface Plasmon vibration. The detail characterization of the nanoparticles was carried out using UV-Vis spectrometry at 400-700nm, maximum absorption peak was observed at 470nm. FTIR analysis showed the functional groups involved in the AgNPs formation. Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) revealed the spherical structure of nanoparticles and the average parti cle size was found to be in between 5-60nm respectively. Antibacterial activity of synthesized silver nanoparticles (AgNPs) was carried out for both Gram negative and Gram positive bacteria and compared with standard antibiotic Ampicillin.
Uv-vis absorption spectrum of synthesized silver nanoparticles after 15min at 60°C. 3.1 UV-Vis spectrophotometer: The UV-Vis spectroscopy was the preliminary technique for the characterization of the silver nanoparticles. The UVVis absorption was analyzed after centrifuging and redispensing the particles in deionized water, the maximum broad absorption peak was observed at 470nm (Fig. 2) was confirmed that polydispersed nanoparticles were formed. 3.2 FTIR analysis of silver nanoparticles: The FTIR analysis is the technique used for the identification of change in functional groups. The reduced sample was centrifuged and powdered to stable form. FTIR
Uv-vis absorption spectrum of synthesized silver nanoparticles after 15min at 60°C. 3.1 UV-Vis spectrophotometer: The UV-Vis spectroscopy was the preliminary technique for the characterization of the silver nanoparticles. The UVVis absorption was analyzed after centrifuging and redispensing the particles in deionized water, the maximum broad absorption peak was observed at 470nm (Fig. 2) was confirmed that polydispersed nanoparticles were formed. 3.2 FTIR analysis of silver nanoparticles: The FTIR analysis is the technique used for the identification of change in functional groups. The reduced sample was centrifuged and powdered to stable form. FTIR
… 
SEM image of silver nanoparticles synthesized from Cajanus Cajan leaf extract at magnification of x4.06 K 3.3 SEM analysis: The silver nanoparticles synthesized by using Cajanus cajan leaf extract were scanned using Scanning Electron Microscope. The images showed relatively spherical shaped nanoparticles were observed at a magnification of x4.06 K (Fig. 4). The high density crystalline powdered silver nanoparticles synthesized by the leaf extract were found to be 5-60 nm (Fig .4). This confirms the silver nanoparticles were formed by Cajanus cajan leaf extract. TEM analysis: Transmission Electron Microscopy gave a detailed descriptive image of the silver nanoparticles synthesized with their structural details and their size. The synthesized silver nanoparticles were scanned using TEM from which we conclude that the average mean size of silver nanoparticles was in between 5-60 nm (Fig. 5D) and seems to be spherical in morphology as shown in (Fig. 5A and 5B), The silver particles are crystalline, as can be seen from the selected area diffraction pattern recorded from one of the nanoparticles in the aggregates as shown in Fig. 5C.
SEM image of silver nanoparticles synthesized from Cajanus Cajan leaf extract at magnification of x4.06 K 3.3 SEM analysis: The silver nanoparticles synthesized by using Cajanus cajan leaf extract were scanned using Scanning Electron Microscope. The images showed relatively spherical shaped nanoparticles were observed at a magnification of x4.06 K (Fig. 4). The high density crystalline powdered silver nanoparticles synthesized by the leaf extract were found to be 5-60 nm (Fig .4). This confirms the silver nanoparticles were formed by Cajanus cajan leaf extract. TEM analysis: Transmission Electron Microscopy gave a detailed descriptive image of the silver nanoparticles synthesized with their structural details and their size. The synthesized silver nanoparticles were scanned using TEM from which we conclude that the average mean size of silver nanoparticles was in between 5-60 nm (Fig. 5D) and seems to be spherical in morphology as shown in (Fig. 5A and 5B), The silver particles are crystalline, as can be seen from the selected area diffraction pattern recorded from one of the nanoparticles in the aggregates as shown in Fig. 5C.
… 
: Transmission electron microscopy characterization of green synthesized Cajanus cajan silver nano particles. a) TEM images of silver nanoparticles, scale bar: 200nm b) TEM image of silver nano particles, scale bar; 100nm c) Selected area of electron diffraction pattern of silver nanoparticles d) Histogram of particle size distribution of silver nanoparticles. 3.4 Antibacterial activity by disc diffusion technique: Antibacterial activity of green synthesized silver nanoparticles against Gram negative Escherichia coli and Gram positive Staphylococcus aureus, [19] bacteria at different concentrations showed that they revealed a strong dose-dependent antibacterial activity against the test microorganisms. It was seen that, as the concentration of green synthesized nanoparticles were increased, bacterial growth decreases in both the cases. The zone of inhibition of silver nanoparticles against Gram positive bacteria Staphylococcus aureus and Gram negative bacteria Escherichia coli shown in (Fig.6A, 6B) and (Table 2). The results indicated that silver nanoparticles synthesized from Cajanus cajan leaf extract showed effective antibacterial activity in Gram positive than in Gram negative bacteria respectively.
: Transmission electron microscopy characterization of green synthesized Cajanus cajan silver nano particles. a) TEM images of silver nanoparticles, scale bar: 200nm b) TEM image of silver nano particles, scale bar; 100nm c) Selected area of electron diffraction pattern of silver nanoparticles d) Histogram of particle size distribution of silver nanoparticles. 3.4 Antibacterial activity by disc diffusion technique: Antibacterial activity of green synthesized silver nanoparticles against Gram negative Escherichia coli and Gram positive Staphylococcus aureus, [19] bacteria at different concentrations showed that they revealed a strong dose-dependent antibacterial activity against the test microorganisms. It was seen that, as the concentration of green synthesized nanoparticles were increased, bacterial growth decreases in both the cases. The zone of inhibition of silver nanoparticles against Gram positive bacteria Staphylococcus aureus and Gram negative bacteria Escherichia coli shown in (Fig.6A, 6B) and (Table 2). The results indicated that silver nanoparticles synthesized from Cajanus cajan leaf extract showed effective antibacterial activity in Gram positive than in Gram negative bacteria respectively.
… 
: Antibacterial activity of Cajanus cajan Silver nano particles using (A) Staphylococcus aureus ( B) Escherichia coli (1mg/ml solution: discs containing 1= 10μl of CjAgNPs, 2=5μl of CjAgNPs, 3=10μl of leaf extract, 4=10μl of Ampicillin) Conclusion: In this study, silver nanoparticles which were synthesized from Cajanus cajan leaf extract showed antibacterial activity against Gram positive and Gram negative bacterial
: Antibacterial activity of Cajanus cajan Silver nano particles using (A) Staphylococcus aureus ( B) Escherichia coli (1mg/ml solution: discs containing 1= 10μl of CjAgNPs, 2=5μl of CjAgNPs, 3=10μl of leaf extract, 4=10μl of Ampicillin) Conclusion: In this study, silver nanoparticles which were synthesized from Cajanus cajan leaf extract showed antibacterial activity against Gram positive and Gram negative bacterial
… 
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39
International Journal of Nanomaterials and Biostructures 2012; 2(3) 39-43
ISSN 2277-3851
Original Article
Green Synthesis and characterization of Silver nanoparticles from Cajanus cajan
leaf extract and its antibacterial activity
Veera babu Nagati, Rama Koyyati, Manisha R Donda, Jahnavi Alwala, Karunakar Rao Kundle
Pratap Rudra Manthur Padigya*
Department of Biochemistry, Osmania University, Hyderabad, India-500007
Corresponding author E-mail: mpprataprudra@gmail.com
Received 21 August 2012; accepted 08 September 2012
Abstract
Nanoparticles, because of their diversified applications in the field of modern medicine are an important thrust area. So, in
the present investigation synthesis and characterization of Silver nanoparticles (AgNPs), and their antimicrobial effect on
bacteria were studied. By using leaf extracts of Cajanus cajan (pigeon pea), AgNPs were prepared by green synthesis
process from 1mM AgNO3 solution. The color change observed after the addition of AgNO3 was due to the surface
Plasmon vibration. The detail characterization of the nanoparticles was carried out using UV-Vis spectrometry at 400-
700nm, maximum absorption peak was observed at 470nm. FTIR analysis showed the functional groups involved in the
AgNPs formation. Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy
(HRTEM) revealed the spherical structure of nanoparticles and the average particle size was found to be in between 5-
60nm respectively. Antibacterial activity of synthesized silver nanoparticles (AgNPs) was carried out for both Gram
negative and Gram positive bacteria and compared with standard antibiotic Ampicillin.
© 2011 Universal Research Publications. All rights reserved
Key Words: Cajanus cajan, Green synthesis, UV-Vis spectrometry, surface Plasmon vibration, Transmission electron
microscopy, Antibacterial activity.
1. INTRODUCTION:
Nanotechnology provides the tools and technology
platform for the investigation and transformation of
biological systems, and biology offers inspiration models
and bio-assembled components to nanotechnology.
Nanobiotechnology is defined as a field that applies the
nanoscale principle and techniques to understand and
transform bio systems (living and non-living) and which
uses biological principles and materials to create new
devices and systems integrated from the nanoscale [1]. Key
advances have been made in the ability to make
measurements at the sub-cellular level and in understanding
the cell as highly organized, self-repairing, self-replicating,
information rich molecular machines [2, 3]. Smalley,
classified nanotechnologies into wet and dry
nanotechnology, the first one describes the living bio
systems and second one deals with man-made objects at
nanoscale structures. [4]
Among the different living organisms used for
nanoparticles synthesis, plants are of particular interest in
metal nanoparticles synthesis because of its advantage over
other environmentally benign biological process as it
eliminates the elaborate process of maintaining cell cultures
[4–6]. Plant mediated synthesis of nanoparticles is gaining
importance due to its simplicity and ecofriendlines.
Silver has long been recognized as having inhibitory effect
on microbes present in medical and industrial process [3 &
4]. The most important application of silver nanoparticles
in medical industry is topical ointments to prevent infection
against burn and open wounds [5]. The reduction of Ag+
ions by combinations of bio molecules found in the extracts
such as vitamins, enzymes/proteins, organic acids such as
citrates, amino acids, and polysaccharides [6]. Currently,
the investigation of this fact has regained importance due to
the increased bacterial resistance to antibiotics, caused by
their over usage. Many evidence based studies of the past
shows that there is virtually no bacterial strain resistant to
silver’s powerful antibacterial effects. Recently, silver
nanoparticles exhibiting antimicrobial activity have been
synthesized and research is on the way for its development
for therapeutic use.
The search for plants with antibacterial activity has gained
increasing importance in recent years due to the
development of antimicrobial drug resistance and often the
occurrence of undesirable side effects of some antibiotics
[7]. With the advent of ever increasing resistant bacteria
and yeast strains, there has been a corresponding rise in the
universal demand for natural antimicrobial therapeutics.
Available online at http://www.urpjournals.com
International Journal of Nanomaterials and Biostructures
Universal Research Publications. All rights reserved
40
International Journal of Nanomaterials and Biostructures 2012; 2(3) 39-43
Fig 1(A) Cajanus cajan plant (Pigeon pea)
(B) Leaf extract of Cajanus cajan
(C) Reddish brown solution of silver nanoparticles formed due to the reduction.
About 80% of developing countries use traditional
medicine based on plant products. Plants are safer
alternative sources of antimicrobials [8, 9].
Cajanus cajan is a perennial member of the family
Leguminaceae, commonly known as ‘pigeon pea’ or red
gram. It is one of the most important dietary legume crop
predominantly grown in the tropical regions. India
contributes about 90% of the world production of Cajanus
cajan. Compared with other grain legumes, pigeon pea
ranks only sixth in area and production, but it is used in
more diverse ways than others [10]. The extracts or
components of pigeon pea are commonly used all over the
world for the treatment of diabetes, dysentery and hepatitis
[11] now a days these leaves are used for the treatment of
wounds, naphtha, bedsores and malaria as well as diet-
induced hypercholesterolemia [12]. Chemical constituent
investigations have indicated that pigeon pea leaves are rich
in flavonoids, stilbenes which are considered responsible
for the beneficiaries of the leaves on human health [13 &
14]. In the present scenario of emergence of multidrug
resistance to human pathogenic infections, it has become
necessary to search for new antimicrobial substances from
other sources such as plants [15]. So an invention of super
drugs using colloidal silver nanoparticles is very imperative
to kill the superbugs.
In view of the importance of Cajanus cajan and silver
nanoparticles, the present work has been planned to
synthesize and investigate the antibacterial activity of silver
nanoparticles synthesized from the leaf extracts of Cajanus
cajan using AgNO3 against some bacteria.
2. MATERIALS AND METHODS:
2.1 Collection of leaves:
Cajanus cajan Leaves (Fig.1A) were collected from the
campus of Osmania University, Andhra Pradesh, India. The
leaves were rinsed thrice with distilled water followed by
double distilled water to remove the dust and other
contaminants then dried at room temperature to remove the
moisture for 4 hours.
2.2 Preparation of leaf extract:
15gms of green leaves were weighed and then sliced into
small pieces. Then 100ml of double distilled water was
added and boiled for 15min at 60°C. After cooling the
extract was filtered using whatman No.1 filter paper and
stored at 4°C for further use. (Fig. 1B)
2.3 Preparation of 1mM AgNO3 solutions:
Accurate concentration of 1mM silver nitrate (Sigma
grade, USA) can be prepared by dissolving 0.0421gms
AgNO3 in 250ml of double distilled water and stored in
amber colored bottle to prevent auto oxidation of silver.
(Chemicals used were of Sigma grade, USA).
2.4 Green synthesis of Cajanus cajan leaf silver
nanoparticles:
For the synthesis of silver nanoparticles from Cajanus
cajan leaf extract, to 20ml of extract, 80ml of 1mM AgNO3
solution was added and further heated up to 60°C for
15minutes. The color change was observed, which stands
as a preliminary confirmation for the formation of silver
nanoparticles. Further the solution was centrifuged at
20000rpm for 30min. The separated nanoparticles settled at
the bottom were collected and washed thrice with double
distilled water, then dried in an oven at 60oC for two hours.
The stabilized powder forms of the nanoparticles were
stored for further characterization.
2.5 Characterization of Cajanus cajan silver
nanoparticles (CjAgNPs):
An ELICO SL-159 UV-Vis spectrophotometer was used
for the spectrometric analysis to confirm silver
nanoparticles formation. The leaf extract was used as
reference blank. The purified suspension was oven dried
and the powder was subjected to FTIR spectroscopy
analysis (Paragon 500, Perkin Elmer-RX1
spectrophotometer) in the diffuse reflectance mode at a
resolution of 4cm−1 in KBr pellets. Further the morphology
of synthesized AgNPs was determined by using SEM in
Zeiss 700 Scanning electron microscope. In addition to
SEM, Transmission electron microscope (TEM) was used
41
International Journal of Nanomaterials and Biostructures 2012; 2(3) 39-43
for characterizing size and shape of green synthesized
silver nanoparticles in Philips model CM 200 instrument
operated at an accelerating voltage at 200 kV.
2.6 Antibacterial activity using Disc Diffusion method:
The antimicrobial activity of synthesized silver
nanoparticles was determined using disc diffusion assay
method. Luria Bertani media was prepared and poured into
sterilized petriplates and then plates were spreaded with
Micrococcus luteus, Staphylococcus aureus and
Escherichia coli, separately. Then sterile discs were kept
and the samples were added in different concentrations to
the disc and plates were incubated at 37°C for 24 hours.
Then zone of inhibition was measured.
3. Results and discussion:
The synthesis of silver nanoparticles is an advanced
technique in modern nanotechnology and is evolving as an
important branch of nanotechnology. This study deals with
the synthesis and characterization of silver nanoparticles
using leaf extract of Cajanus cajan (pigeon pea).
Synthesized silver nanoparticles were reddish brown in
color. The color of the extract was changed from light
yellowish to reddish brown after addition of AgNO3 and on
incubation for 15min at 60ºC. The coloration was due to the
excitation of the surface Plasmon vibration in the silver
nanoparticles [16]. Change in color after the reduction of
Ag+ to silver nanoparticles is shown in (Fig. 1C). The
reduction rate and formation of nanoparticles can be
increased further by increase in temperature [17]. The
bactericidal effect [25-27] of CjAgNPs was measured by
disc diffusion method.
Fig 2: Uv-vis absorption spectrum of synthesized silver
nanoparticles after 15min at 60°C.
3.1 UV-Vis spectrophotometer:
The UV-Vis spectroscopy was the preliminary technique
for the characterization of the silver nanoparticles. The UV-
Vis absorption was analyzed after centrifuging and
redispensing the particles in deionized water, the maximum
broad absorption peak was observed at 470nm (Fig. 2) was
confirmed that polydispersed nanoparticles were formed.
3.2 FTIR analysis of silver nanoparticles:
The FTIR analysis is the technique used for the
identification of change in functional groups. The reduced
sample was centrifuged and powdered to stable form. FTIR
Fig 3: FTIR analysis of Cajanus cajan silver nanoparticles.
study showed peaks at 3415cm-1[20],3018cm-1.2880cm-1,
aliphatic amine (C-H), 2372cm-1, 1616cm-1 carboxylic acid,
[21], 1436 cm-1, aromatic amine (C-N) [18,22 &23] 1373cm-
1[22 & 23], 1218cm-1[23], 1069cm-1[24], 603cm-1. FTIR
spectrum in the Fig. 3 showed the aliphatic amine, and
aliphatic alkenes of alkaloids and terpenoids bound on the
surface of CjAgNPs.
Fig 4: SEM image of silver nanoparticles synthesized from
Cajanus Cajan leaf extract at magnification of x4.06 K
3.3 SEM analysis:
The silver nanoparticles synthesized by using Cajanus
cajan leaf extract were scanned using Scanning Electron
Microscope. The images showed relatively spherical
shaped nanoparticles were observed at a magnification of
x4.06 K (Fig. 4). The high density crystalline powdered
silver nanoparticles synthesized by the leaf extract were
found to be 5-60 nm (Fig .4). This confirms the silver
nanoparticles were formed by Cajanus cajan leaf extract.
TEM analysis:
Transmission Electron Microscopy gave a detailed
descriptive image of the silver nanoparticles synthesized
with their structural details and their size. The synthesized
silver nanoparticles were scanned using TEM from which
we conclude that the average mean size of silver
nanoparticles was in between 5-60 nm (Fig. 5D) and seems
to be spherical in morphology as shown in (Fig. 5A and
5B), The silver particles are crystalline, as can be seen from
the selected area diffraction pattern recorded from one of
the nanoparticles in the aggregates as shown in Fig. 5C.
42
International Journal of Nanomaterials and Biostructures 2012; 2(3) 39-43
Fig 5: Transmission electron microscopy characterization
of green synthesized Cajanus cajan silver nano particles.
a) TEM images of silver nanoparticles, scale bar: 200nm
b) TEM image of silver nano particles, scale bar; 100nm
c) Selected area of electron diffraction pattern of silver
nanoparticles
d) Histogram of particle size distribution of silver
nanoparticles.
3.4 Antibacterial activity by disc diffusion technique:
Antibacterial activity of green synthesized silver
nanoparticles against Gram negative Escherichia coli and
Gram positive Staphylococcus aureus, [19] bacteria at
different concentrations showed that they revealed a strong
dose-dependent antibacterial activity against the test
microorganisms. It was seen that, as the concentration of
green synthesized nanoparticles were increased, bacterial
growth decreases in both the cases. The zone of inhibition
of silver nanoparticles against Gram positive bacteria
Staphylococcus aureus and Gram negative bacteria
Escherichia coli shown in (Fig.6A, 6B) and (Table 2). The
results indicated that silver nanoparticles synthesized from
Cajanus cajan leaf extract showed effective antibacterial
activity in Gram positive than in Gram negative bacteria
respectively.
Fig 6: Antibacterial activity of Cajanus cajan Silver nano
particles using
(A) Staphylococcus aureus (B) Escherichia coli
(1mg/ml solution: discs containing 1= 10µl of CjAgNPs,
2=5µl of CjAgNPs, 3=10µl of leaf extract, 4=10µl of
Ampicillin)
Conclusion:
In this study, silver nanoparticles which were synthesized
from Cajanus cajan leaf extract showed antibacterial
activity against Gram positive and Gram negative bacterial
strains. Further, Zone of inhibition was performed against
Ampicillin and leaf extract which was used as a control
respectively. Thus it is proven from this study that the
silver nanoparticles synthesized from Cajanus cajan leaf
extract seems to be promising and effective antibacterial
agent against bacterial strains. This green chemistry
approach towards the synthesis of silver nanoparticles is
highly essential effort being addressed in nanomedicine
because of its varied advantages. Plant extract being very
eco friendly and cost effective can be used for the large
scale synthesis of silver nanoparticles in nanotechnology
processing industries.
Acknowledgement:
The author acknowledges department of Physics, Osmania
University Hyderabad for providing support in carrying out
SEM analysis.
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Silver nanoparticles were green synthesized using the aqueous extract of Citrus pennivesiculata (Lush.) Tanaka, J. fruit peel. The metallic silver was reduced to silver nanoparticles by the action of secondary metabolites in the fruit peel. The characterization of silver nanoparticles was done by UV-visible spectrophotometry, transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). UV-vis spectrophotometry of the silver nanoparticles showed an absorption peak at 435 nm. The TEM analysis showed that the spherical diameter of the particle ranged between 2 to 34 nm. The XRD analysis proved the crystalline nature of the synthesized silver nanoparticles. The FTIR analysis of the synthesized nanoparticles showed the presence of alcohols, phenols, aromatic esters, monosubstituted alkynes, disubstituted alkenes, sulfoxide, amino, and other functional groups. Cytotoxicity and anticancer activity of the green synthesized silver nanoparticles were determined using the mouse fibroblast cell line (L929) and human breast cancer cell line (MCF-7), respectively. The lethal concentration (LC50) of silver nanoparticles on the L929 cell line was found to be 48.521 µg/mL, and that of the MCF-7 cell line was 21.625816 µg/mL. The synthesized silver nanoparticles revealed cytotoxic activity in a dose-dependent manner. The conclusions drawn from this research could be beneficial for nanotechnology-based biomedical applications
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... The plant extracts possessing biomolecules such as saponins, proteins, polysaccharides, amino acids, phenolic, alkaloids, terpenoids, enzymes, tannins, and vitamins help in stabilization and reduction of nickel ions and are environmentally benign. The complex structures of these biomolecules makes it a good stabilizing and capping agent [4]. ...
 View Online  Export Citation CrossMark Indian bay leaf moderated synthesis of silver nanoparticles and their versatile applications  Articles You May Be Interested In A functional integral formalism for quantum spin systems Indian Bay Leaf Moderated Synthesis of Silver Nanoparticles and their Versatile Applications
Article
Full-text available
  • Sep 2023
Silver nano particles holds an extensive variety of applications in diverse fields ranging from photonics to electronics, bio-sensors, conducting materials, space, medicine, pollution control and monitoring. Nanoparticles are on its way to conquer world with its peculiar properties like electric conductivity, optical properties, good biocompatibility etc. These nanoparticles on combining with other materials in preparation of composite material can enhance property of materials or the properties can be toned. Cinnamomum tamala leaf, which is a common herb, widely used for culinary and medicinal purposes in India is used as the substrate for the study. The synthesized nanoparticles were characterized by UV-Visible spectroscopy and X-Ray diffraction. Further, the prepared nanoparticles were studied for its environmental application in the detection of heavy metal and finally pave way for the development of biosensors in an ecofriendly and cost-effective way. In addition, the anti-bacterial and anti-fungicidal properties of the particles synthesized were assessed following standard procedures and they exhibit excellent anti-microbial activity against bacteria.
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... The plant extracts possessing biomolecules such as saponins, proteins, polysaccharides, amino acids, phenolic, alkaloids, terpenoids, enzymes, tannins, and vitamins help in stabilization and reduction of nickel ions and are environmentally benign. The complex structures of these biomolecules makes it a good stabilizing and capping agent [4]. ...
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... Nanotechnology has become very popular in every field of science (physics, chemistry, and biology) that involve with the production of several forms of material including nanoparticles, NPs [1][2][3][4][5][6][7]. Nowadays, NPs are extensively applied in enhancing various food production systems including aquaculture [8][9][10] due to having different physicochemical attributes especially their medicinal as well as nutritional roles [11][12][13][14]. NPs play very important role to boost up aquaculture production through stimulating the activity of several nutrient molecules such as micronutrients [15,16]. ...
Comparative Effect of Chemical and Green Zinc Nanoparticles on the Growth, Hematology, Serum Biochemical, Antioxidant Parameters, and Immunity in Serum and Mucus of Goldfish, Carassius auratus (Linnaeus, 1758)
Article
Full-text available
  • Jul 2023
  • BIOL TRACE ELEM RES
Recently, nano feed supplement research has great attention to improving healthy aquatic production and improving the aquatic environment. With the aims of the present study, chemical and green synthesized nanoparticles are characterized by various instrumentation analyses, namely UV-Vis spectrophotometry (UV-Vis), X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy, and scanning electron microscope (SEM). After characterization analysis of these nanoparticles utilized in aquatic animals, the composition ratio is as follows: controls (without ZnO-NPs (0 mg/L)), T1 (0.9 mg/L ZnO-NPs), T2 (1.9 mg/L ZnO-NPs), T3 (0.9 mg/L GZnO-NPs), T4 (1.9 mg/L GZnO-NPs). SEM investigation report demonstrates that the structure of the surface of green synthesized zinc oxide nanoparticles (GZnO-NPs) was conical shape and the size ranging was from 60 to 70 nm. Concerning hematological parameters, the quantity of hemoglobin increased in different doses of green zinc nanoparticles, but the values of MCV and MCH decreased somewhat. However, this decrease was the highest in the T2 group. Total protein and albumin decreased in T2 and triglyceride, cholesterol, glucose, cortisol, creatinine, and urea increased, while in T3 and T4 groups, changes in biochemical parameters were evaluated as positive. Mucosal and serum immunological parameters in the T2 group showed a significant decrease compared to other groups. In zinc nanoparticles, with increasing dose, oxidative damage is aggravated, so in the T2 group, a decrease in antioxidant enzymes and an increase in MDA were seen compared to other groups. In this regard, the concentration of liver enzymes AST and ALT increased in the T2 group compared with control and other groups. This can confirm liver damage in this dose compared with control and other groups. This research work suggests that green synthesized form of zinc nanoparticles in higher doses have less toxic effects in comparison to the chemical form of zinc nanoparticles and can act as suitable nutrient supplements in aquatic animals.
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... In our study, the SEM analysis showed that the particles were shaped like spheres with rough surfaces, which agrees with the results reported by Raj et al. [46]. Additionally, the TEM analysis showed that the AgNPs were monodispersed and sphere-shaped, as in the results reported by Nagati et al. [47], who synthesized AgNPs from Cajanus cajan leaf extract and proved their antibacterial activity. The AgNPs were not agglomerated, as the EDX analysis yielded highly conclusive results, confirming the silver's existence. ...
Rhizobium leguminosarum bv. viciae-Mediated Silver Nanoparticles for Controlling Bean Yellow Mosaic Virus (BYMV) Infection in Faba Bean Plants
Article
Full-text available
  • Dec 2022
The faba bean plant (Vicia faba L.) is one of the world’s most important legume crops and can be infected with various viral diseases that affect its production. One of the more significant viruses in terms of economic impact is bean yellow mosaic virus (BYMV). The current study used the molecularly identified Rhizobium leguminosarum bv. viciae strain 33504-Borg1, a nitrogen-fixing bacteria, to biosynthesize silver nanoparticles (AgNPs) to control BYMV disease in faba bean plants. Scanning electron microscopy (SEM), a particle size analyzer (PSA) with dynamic light scattering (DLS), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FTIR) were used to characterize the prepared AgNPs. The DLS, SEM, and TEM analyses revealed that the AgNPs were spherical and rough, with sizes ranging from 13.7 to 40 nm. The FTIR analysis recognized various functional groups related to AgNP capping and stability. Under greenhouse conditions, spraying faba bean leaves with the AgNPs (100 µg/mL) 24 h before BYMV inoculation induced plant resistance and reduced plant disease severity and virus concentration levels. Contrarily, the AgNP treatment enhanced plant health by raising photosynthetic rates, increasing the fresh and dry weight of the faba bean plants, and increasing other measured metrics to levels comparable to healthy controls. Antioxidant enzymes (peroxidase and polyphenol oxidase) inhibited the development of BYMV in the faba bean plants treated with the AgNPs. The AgNPs decreased oxidative stress markers (H2O2 and MDA) in the faba bean plants. The plants treated with the AgNPs showed higher expression levels of PR-1 and HQT than the control plants. The study findings could be used to develop a simple, low-cost, and environmentally friendly method of protecting the faba bean plant from BYMV.
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... Leaf extract of Cajanus cajan (L.) (pigeon pea) was used for facile green synthesis of AgNPs by Nagati et al. (2012). C. cajan leaf extract was added with 1 mM of AgNO 3 that was further heated at 60°C for 15 min. ...
Crop-mediated synthesis of nanoparticles and their applications
Chapter
  • Jan 2022
The application of nanotechnology has been extended to food, pharmaceutical, energy, textiles, and even catalysis in the past decades. The attractive physicochemical and optoelectronic properties of nanoparticles are exploited for diagnosis and targeted drug delivery. The available physical and chemical methods for the synthesis of nanoparticles involve toxic chemicals and hazardous reaction conditions apart from high energy consumption. Moreover, often, the resulting nanoparticles are cytotoxic due to the association of harmful chemicals used during synthesis. Hence, biological routes for the synthesis of nanoparticles using viruses, bacteria, fungi, algae, and plants are being developed to address the aforementioned limitations. This chapter particularly describes the role of crops in the fabrication of various types of nanoparticles. Several metallic nanostructures with elemental copper, gold, silver, iron, nickel, and zinc are reported to be synthesized using extracts of crops such as cereals (Oryza sativa, Triticum aestivum, Zea mays L.), pulses (Cajanus cajan L., Cicer arietinum L.), vegetables (Solanum tuberosum, Coriandrum sativum L., Zingiber officinale), spices (Curcuma longa L., Piper nigrum), fruits (Ficus carica, Cynometra ramiflora), and cash crops (Camellia sinensis, Coffea arabica). Further, the applications of these biogenic nanoparticles for photocatalytic dye degradation, optical device fabrication, antimicrobial, anticancer, and larvicidal activities are also discussed. Eventually, the future scope of the environmentally benign, rapid, and efficient route for the synthesis of nanoparticles using crops for designing novel nanocomposites for biomedical and industrial application is presented. In view of the background, it can be concluded that crops can play a vital role in the advancement of nanobiotechnology for the green synthesis of nanoparticles.
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... After mixing with maltodextrin, the concentrated papaya leaf juice is conveyed into the spray drying machine with a feed flow rate of 350 mL/h and inside temperature of 130°C. Papaya leaf powder is stored under normal room temperature conditions [108]. ...
Carica papaya L. Leaves: Deciphering Its Antioxidant Bioactives, Biological Activities, Innovative Products, and Safety Aspects
Article
Full-text available
The prevalence of viral infections, cancer, and diabetes is increasing at an alarming rate around the world, and these diseases are now considered to be the most serious risks to human well-being in the modern period. There is a widespread practice in Asian countries of using papaya leaves (C. papaya L.) as herbal medicine, either alone or in combination with prescribed medications, to treat a variety of ailments. The importance of conducting the necessary descriptive studies in order to determine the safety of papaya leaf consumption is also emphasized in the context of their application in the health-care sector. Electronic databases such as Google Scholar, Scopus, and PubMed were used to gather information on papaya leaves, their therapeutic potential, and clinical evidence-based studies. The literature was gathered from publications on papaya leaves, their therapeutic potential, and clinical evidence-based studies. The anti-dengue, anti-cancer, antidiabetic, neuroprotective, and anti-inflammatory effects of papaya leaves discussed in this article are supported by evidence from preclinical, in-vivo, in-vitro, and clinical trial studies, as well as from other sources. Leaves have been investigated for their mechanism of action as well as their potential to be used in the development of novel herbal products for the health business. According to the reports gathered, only a small number of research demonstrated that leaf extract at high concentrations was hazardous to certain organs. The collective literature reviewed in this review provides insights into the use of papaya leaves as a cure for epidemic diseases, highlighting the phytochemical composition and pharmacological attributes of papaya leaves, as well as the results of various pre-clinical and clinical studies that have been conducted so far on the subject. The review clearly demonstrates the successful medical evidence for the use of papaya leaf extracts in the health-care system as a supplemental herbal medication in a variety of clinical settings.
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JPTCP (435-444) Biogenic Synthesis Of Silver Nps Using Haplophyllum Gilesii Leaf Extract And Evaluation Of Its Biological Activities Vol
Article
Full-text available
  • Jan 2023
Nanotechnology has got significant importance in biomedical era in the last two decades. Nanoparticles(NP) being smaller in size are acquiring worldwide attention in the field of science and technology. Moreover, the biosynthesis of nanoparticles from various plant extracts is is profitable and eco-friendly. In the present study Haplophyllum gilesii (Hemsl.) C.C. townsend a narrow endemic plant species reported from Northern Pakistan (1500-4000 meters) was screened first time for synthesis of silver nano-particles(AgNPs) from the leaf extract. The prepared metal nanoparticles (MNPs) were further characterized by using X-ray diffraction (XRD) analysis, UV-visible spectroscopy and Scanning Electron Microscopy (SEM). A comparative antibacterial potential of raw methanolic extract and prepared silver nanoparticles(AgNPs) was evaluated which revealed that Nps exhibited the most pronounced antibacterial potential against Gram-negative and Gram-bacteria positive i-e AgNPs of H. gilesii exhibited significant zone of Inhibition against S. aureus, B. subtiis, E. coli, S. typhi, P. aeruginosa and than the crude extract alone. Similarly, the results of the antioxidant activity of AgNPs of H. gilesii were more significant than crude extract. Hence, the present study proved that H. gilesii might be a good source of potential antibiotics and valuable antioxidants. Moreover, further research is needed to isolate essential bioactive compounds to devise anti-cancerous drugs.
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Biosynthesis of Nanomaterials via Plant Extracts
Chapter
  • Jul 2023
Pathways to Green Nanomaterials: Plants as Raw Materials, Reducing Agents and Hosts is a comprehensive guide that explores the fundamental aspects, synthesis methods, and various applications of nanomaterials derived from plants. This book is designed for postgraduate researchers, engineers, and scientists in the fields of materials science, biotechnology, and chemical engineering, as well as other disciplines involved in nanomaterial production and applications. The book delves into different plant-mediated nanomaterials, analyzing their synthesis mechanisms and discussing the regulation and application prospects of plant synthesis. It covers topics such as nanocellulose, biochar materials, plant exosomes, polyphenol nanoparticles, and the phytotoxicity and uptake of nanomaterials by plants. Additionally, it explores the research progress and applications of plant virus nanoparticles in the medical field, including drug delivery, molecular imaging, and vaccine preparation. Readers will be familiarized with the synthetic methods, characterization, and applications of green nanomaterials, paving the way for future studies on plants and their phytochemical constituents. With its comprehensive coverage of plant-derived nanomaterials and their diverse applications, Pathways to Green Nanomaterials: Plants as Raw Materials, Reducing Agents and Hosts serves as a valuable resource for researchers seeking to understand the potential of plants as sustainable sources for nanomaterial production.
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Nanomaterials in the environment: Behavior, fate, bioavailability, and effects (vol 27, pg 1825, 2008)
Article
Full-text available
  • Dec 2012
The recent advances in nanotechnology and the corresponding increase in the use of nanomaterials in products in every sector of society have resulted in uncertainties regarding environmental impacts. The objectives of this review are to introduce the key aspects pertaining to nanomaterials in the environment and to discuss what is known concerning their fate, behavior, disposition, and toxicity, with a particular focus on those that make up manufactured nanomaterials. This review critiques existing nanomaterial research in freshwater, marine, and soil environments. It illustrates the paucity of existing research and demonstrates the need for additional research. Environmental scientists are encouraged to base this research on existing studies on colloidal behavior and toxicology. The need for standard reference and testing materials as well as methodology for suspension preparation and testing is also discussed.
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Status and Utilization of Medicinal Plants in Rangamati of Bangladesh
Article
Full-text available
  • Dec 2006
This study was conducted to assess the status of medicinal plants of Rangamati and their utilization pattern. Rangamati is a resourceful hilly district in terms of forest products of Bangladesh but that resources, medicinal plants in particular of great value are being depleted rapidly through the area has a great potential_ for that resources. In this study area number of Non tribal households have been decreasing because of their migration to their municipal area (22. 5%) to adjacent union(AU) (15. 62%). The number of medicinal plants and available stocks/house in the Rangamati Municipal Area (RMA) (46. 21) than that of Adjacent Union (11. 87). Highest number among the medicinal plant the occurrence in homesteads Allium cepa was dominent (64 stocks/ha) and homesteads adjacent area of RMA and normal its AU followed by Aloe indicia (16. 48), Mangifera indicia (16. 32) and the other species. These three species were also dominent in their percentage distribution (42. 24%, 10. 88% and 10. 77%) in comparison to other species. The distribution of tree species of medicinal value was dominated in every location and was highest in the central location (71. 21%). The distribution of herb species of medicinal value is maximum in the adjacent area of north adjacent union (3. 17%) and in the homesteads south end (28. 22) of RMA. Among the tribe and non tribe house hold people, 74. 5% people are using medicinal plants and similarly on the other hand only 48% non-tribe people using medicinal plants in RMA. In Adjacent Union 73. 75% people using medicinal plants and 61. 5% non-tribe people using medicinal plant. In case of availability of medicinal plant, fruit utilization was found highest in the following species, Musa Paradisiacal, Aegle marmelos, Dillenia indica, Punica grantum, Curcuma longa, Carica papaya followed by Mangifrea indica, respectively. In case of leaf Aloe indica have 100% for leaf utilization followed by Cajanus cajan is being utilized 37. 90%, Azadirachta indica(30. 39%), Allium cepa (25. 29%), Citrus grandis (19. 32%), Terminalia belerica (16. 59%) respectively. And the minimum utilization of leaf was found Mangifera indica (2. 1%), Emblica officinalis (2. 11%), Sondias mangifera(3. 19%) respectively hence less dominent. The status of Medicinal plants were not up to the desired level. For the optimum development of these resources proper steps like encouraging people, providing finacial support and over all monitoring the activities that's are set by government and NGOs(Non-government organization). People should informed about their necessity and the benefits that they might get from these species.
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Nanotechnology in medicine and antibacterial effect of silver nanoparticles
Article
Full-text available
  • Sep 2008
  • DIG J NANOMATER BIOS
Nanotechnology is expected to open some new aspects to fight and prevent diseases using atomic scale tailoring of materials. The ability to uncover the structure and function of biosystems at the nanoscale, stimulates research leading to improvement in biology, biotechnology, medicine and healthcare. The size of nanomaterials is similar to that of most biological molecules and structures; therefore, nanomaterials can be useful for both in vivo and in vitro biomedical research and applications. The integration of nanomaterials with biology has led to the development of diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drug delivery vehicles. In all the nanomaterials with antibacterial properties, metallic nanoparticles are the best. Nanoparticles increase chemical activity due to crystallographic surface structure with their large surface to volume ratio. The importance of bactericidal nanomaterials study is because of the increase in new resistant strains of bacteria against most potent antibiotics. This has promoted research in the well known activity of silver ions and silver-based compounds, including silver nanoparticles. This effect was size and dose dependent and was more pronounced against gram-negative bacteria than gram-positive organisms.
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Ultradilute Ag-aquasols with extraordinary bactericidal properties: Role of the system Ag-O-H2O
Article
Full-text available
  • Mar 2007
We first establish the literature on the use of ultradilute aquasols as extraordinary, powerful, bactericidal inorganic agents equal to most commercial antibiotics. These findings provide the rationale for a major role for inorganic materials scientists to contribute the insights unique to their field for new, safer health vectors. The focus of this preliminary paper is exclusively on the materials science of 2-phase stable sols at ultradilute concentrations near 1 at.-ppm. We analyze the solid and liquid phases for the first time in detail using standard materials science analysis tools. The solid phase is analyzed using DTA, TGA, XRD, SEM, and TEM, and the liquid water phase is analyzed using FTIR, UV-VIS, and Raman spectroscopy. There are at least three crystalline phases in the system Ag-O: Ag, Ag2O, and Ag4O4, which are stable in air. In an aqueous environment between 0 and 100uC there is evidence that various combinations of metal, oxides, and possible 'oxy-hydroxide' complexes exist. Similarly, data from Raman and UV-VIS spectroscopy show definite changes in the structure of the water host. These results, in a preliminary way, are parallel to the many empirical observations made by physicians for the last 100 years on the use of metallic silver and water in various combinations for human health.
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Ethnobotanical potentials of common herbs in Nigeria: A case study of Enugu state
Article
  • Apr 2006
Research was carried out on the ethnobotanical potentials of common herbs in Nigeria using Enugu State as a case study. A total of 200 questionnaires were administered on herb sellers in major herb markets in the state. In all, 96 different plant species were encountered in the markets. Attempts were made to write the names of the species both in botanical and English languages as well as in the three major languages in Nigeria (Yoruba, Igbo and Hausa). The families of the species were also documented. Finally, the various uses of the species and the part(s) of the plant species used were highlighted. This will surely be of great assistance to researchers, herb sellers and the entire consumers in overcoming the long standing problems of communication and identification
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Process parameter optimization for instant pigeonpea dhal using response surface methodology
Article
  • Jul 2007
  • J FOOD ENG
Designed experiments were conducted to study the effects of salt solutions and their concentration, soaking time and cooking time on quality of instant pigeonpea dhal and to optimize their levels. Sodium carbonate, sodium bicarbonate and ammonium carbonate were used individually and in combination. The salt concentration varied from 1.93% to 4.73%. The soaking time ranged between 22 and 38min. Cooking time was in the range 95–146s. The results of the study showed that instant pigeonpea dhal could be prepared by soaking dhal in salt solution, cooking and drying at 65°C. The soaking time and cooking time showed significant effect on expansion ratio and rehydration ratio of pigeonpea dhal, while salt concentration had insignificant effect. Ammonium carbonate was most effective in its effect of rendering instantization characteristics to the pigeonpea dhal. In general, the samples with more expansion ratio exhibited higher rehydration ratio. The expansion ratio and rehydration ratio were optimized and common range of parameters was selected by overlapping their contour plots. The optimum conditions were different for different salt solutions.
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Phytosynthesis of gold nanoparticles using leaf extract of Coleus amboinicus Lour
Article
  • Nov 2010
  • MATER CHARACT
Present study reports a green chemistry approach for the biological synthesis of gold nanoparticles by using the leaf extract of Coleus amboinicus Lour. The nanoparticles were structurally characterized by UV–Vis spectroscopy, XRD, TEM and SAED analyses. Elemental and vibrational analyses were done with EDAX and FT–IR spectroscopies respectively. Bioreduction of gold ions by C. amboinicus leaf extract resulted in the synthesis of spherical, truncated triangle, triangle, hexagonal and decahedral nanoparticles. These nanoparticles showed an absorption peak at 536nm in UV–Vis spectrum corresponding to the plasmon resonance of gold nanoparticles. The size of gold nanoparticles ranged from 4.6 to 55.1nm. FT–IR spectrum confirmed the involvement of aromatic amines, amide (II) groups and secondary alcohols in capping and reduction of gold nanoparticles. Extracellular synthesis of gold nanoparticles is a simple, cheap and environmentally benign alternative to physical and chemical procedures.
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Simultaneous Determination of Four Flavonoids in Pigeonpea [Cajanus cajan (L.) Millsp.] Leaves Using RP-LC-DAD
Article
  • Jan 2006
A simple and accurate RP-HPLC method using photodiode array detection (PAD) was developed for the simultaneous determination of four flavonoids, namely quercetin (QU),luteolin(LU),apigenin(AP) and isorhamnetin (IS) in pigeonpea leaves.Extract samples were separated on HIQ SIL C18V column using methanol-acetonitrile-water(31:10:59, v/v/v) as mobile phase.The flavonoids were detected at 254.5 nm for QU and IS, and at 345 nm for LU and AP.Contents were determined with satisfactory repeatability (R. S. D. < 2.2%) and recovery (97.27 – 99.98%). The developed method was found to be simple and efficient.
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