Silvernanoparticles (AgNPs) are one of the most important nanoparticles extensively studied in recent years due to its diverse beneficial properties and wide variety of applications in biological, chemical, and physical sciences. It is proved that silvernanoparticles possess unusual properties such as high antimicrobial activity, particles stability, and surface chemistry. Specific surface plasmon resonance (SPR) peak of silvernanoparticles falls in between 450 and 530 nm. These different wavelengths are able to express different particle sizes, shapes, and surface properties of nanoparticles. Different physical formations lead to AgNPs to be widely used as antimicrobial and antifungal agents in healthcare, food, textile coatings, and electronic device industries. AgNPs which attached to the microbial cell surface cause structural changes of the cells and further lead to cell death by damaging the entire cell functions. Up to date, many commercial products incorporated with AgNPs were approved by FDA (USA), SIAA (Japan), KTR and FITI (Korea) (Kuppusamy et al., 2016).
Antimicrobial assay of biosynthesised silvernanoparticles was studied against E. coli and S. aureus bacteria using agar well diffusion method and zone of inhibition is depicted in figure- 7 and in Table- 1. Plant extract (neem, mango, lemon and combination of all the three leaves) and Silvernanoparticles was loaded into the wells with different concentrations of 20, 40, 60 and 80 micro litres respectively. The silvernanoparticles synthesised by using combination of neem, mango and lemon leaves showed the more antimicrobial activity towards both the bacteria than compare to the silvernanoparticles synthesised by using neem, mango and lemon leaves extract. On the other hand, plant extract alone did not show much antimicrobial activity this may be due to the medium extraction as well as lower concentration during experimentation (4). Thus, from the present research it is indicated that the silvernanoparticles is more effective towards both S. aeurus and E. coli bacteria because the silvernanoparticles not only interact with the surface membrane, but also penetrate inside the bacteria, and it also interact with the DNA of bacteria, preventing cell reproduction (6).
Abstract: The immense potential of nanobiotechnology makes it an intensely researched field in modern medicine. Green nanomaterial synthesis techniques for medicinal applications are desired because of their biocompatibility and lack of toxic byproducts. We report the toxic byproducts free phytosynthesis of stable silvernanoparticles (AgNPs) using the bark extract of the traditional medicinal plant Acacia leucophloea (Fabaceae). Visual observation, ultraviolet– visible spectroscopy, and transmission electron microscopy (TEM) were used to character- ize the synthesized AgNPs. The visible yellow-brown color formation and surface plasmon resonance at 440 nm indicates the biosynthesis of AgNP. The TEM images show polydis- perse, mostly spherical AgNP particles of 17–29 nm. Fourier transform infrared spectroscopy revealed that primary amines, aldehyde/ketone, aromatic, azo, and nitro compounds of the A. leucophloea extract may participate in the bioreduction and capping of the formed AgNPs. X-ray diffraction confirmed the crystallinity of the AgNPs. The in vitro agar well diffusion method confirmed the potential antibacterial activity of the plant extract and synthesized AgNPs against the common bacterial pathogens Staphylococcus aureus (MTCC 737), Bacillus cereus (MTCC 1272), Listeria monocytogenes (MTCC 657), and Shigella flexneri (MTCC 1475). This research combines the inherent antimicrobial activity of silver metals with the A. leucophloea extract, yielding antibacterial activity-enhanced AgNPs. This new biomimetic approach using traditional medicinal plant (A. leucophloea) barks to synthesize biocompatible antibacterial AgNPs could easily be scaled up for additional biomedical applications. These polydisperse AgNPs green-synthesized via A. leucophloea bark extract can readily be used in many applica- tions not requiring high uniformity in particle size or shape.
Metal nanoparticles, particularly silvernanoparticles (AgNPs), are developing more important roles as diagnostic and therapeutic agents for cancers with the improvement of eco-friendly synthesis methods. This study demonstrates the biosynthesis, antibacterial activity, and anticancer effects of silvernanoparticlesusing Dimocarpus Longan Lour. peel aqueous extract. The AgNPs were characterized by UV-vis absorption spectroscopy, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscope (FTIR). The bactericidal properties of the synthesized AgNPs were observed via the agar dilution method and the growth inhibition test. The cytotoxicity effect was explored on human prostate cancer PC-3 cells in vitro by trypan blue assay. The expressions of phosphorylated stat 3, bcl-2, survivin, and caspase-3 were examined by Western blot analysis. The longan peel extract acted as a strong reducing and stabilizing agent during the synthesis. Water-soluble AgNPs of size 9 – 32 nm was gathered with a face-centered cubic structure. The AgNPs had potent bactericidal activities against gram-positive and gram-negative bacteria with a dose-related effect. AgNPs also showed dose-dependent cytotoxicity against PC-3 cells through a decrease of stat 3, bcl-2, and survivin, as well as an increase in caspase-3. These findings confirm the bactericidal properties and explored a potential anticancer application of AgNPs for prostate cancer therapy. Further research should be focused on the comprehensive study of molecular mechanism and in vivo effects on the prostate cancer.
Nanotechnology has tremendous applications in the areas of renewable energy, environmental remediation, drug delivery and pharmaceutical industries. Nanoparticles are cluster of atoms ranging between 1-100 nm in size and these are fundamental building blocks of nanotechnology. The physical and chemical methods have been employed in the synthesis of silvernanoparticles but these methods are tedious and non-ecofriendly with low productivity (1). The chemicals used in the synthesis of nanoparticles are hazardous which leads to environmental pollution. Now-a-days biosynthesis of nanoparticles has been established as an alternative to physical and chemical methods of synthesis of nanoparticles as in the green synthesis of nanoparticles there is no involvement of high pressure, temperature and toxic chemicals (2). Silvernanoparticles have many distinctive properties such as conductivity, chemical stability, catalytic nature, antibacterial, antifungal and anti-inflammatory activities (3). According to Kulkarni et al. (4) synthesis of metal nanoparticles by utilization of plant extracts is a green method as the plants are widely distributed, easily available, safe to handle and they are rich source of secondary metabolites. Plants can be eco-friendly alternative for the
Abstract - The emergence of nanobiotechnology has exposed the greener methods of preparation and application. Many theoretical and experimental works have been conducted in the biosynthesis of various nanomaterials and nanocomposites. Biologically synthesised nanomaterials are exhibiting excellent, unique and optimised properties. Micro organisms play an important role in the detoxification of metals through the reduction of metal ions. This process can be exploited for biosynthesis of NPs. Experiments were conducted by varying the concentrations of silver ions for analysing the formation of silvernanoparticles by Fusarium Oxysporum. The analysis has been done for extracellular and intracellular in the growing cell and whole cell sysytems. Silvernanoparticles formed by Fusarium Oxysporum was found to be purely extracellular. In this paper, from the experimental analysis, an attempt is being made to suggest a mechanism and elucidate the kinetics for the formation of silvernanoparticles.
Fig. 3a and 3b shows the results of the silvernanoparticles formed from the seaweed extract captured by means of SEM. Fig. 3a represents the view of the sample with the magnification of 20,000× could notice from the particles size of 45‑300 nm; however, we could not manage to examine the structure of the observed nanoparticles less than 45 nm because of difficulties connected with getting higher magnification. But huge amount of nanoparticles ranging the sizes between 45 and 75 nm can be visible in fig. 3a. The factor responsible for difficulties connected with getting higher magnification was high susceptibility of nanoparticles to aggregate into larger conglomerates. Fig. 3b shows the formation of triangular silvernanoparticles. The size of these triangular nanoparticles ranged from 200 nm and we could be able to see a large number of particles belonging to the sizes ranging from 45 to 60 nm. Developing a reliable eco‑friendly process for synthesising silvernanoparticles for pharmaceutical applications are off critical need in the field of nanotechnology in recent times. The marine seaweed S. cinereum can produce silver nanostructures through efficient green nanochemistry avoiding the presence of hazardous and toxic solvents and waste. The biosynthesised silvernanoparticlesusing S. cinereum extract proved excellent antimicrobial activity and the
Biosynthesis of silver nanoparticle production: Fungal mat of A. conicus, Penicillium Janthinellum and Phomosis was mixed with silver nitrate solution and incubated in room temperature. The appearance of brown colour was due to the excitation of surface Plasmon vibrations. The control shows no change in colour of the mixture when incubated in the same conditions. The production of silvernanoparticles is high in A.conicus, Penicillium Janthinellum and Phomosis which sources dark brown colour Phomosis. Ahamed et al., (2003) reported that, cell free filtrate of Penicillium sp. was mixed with silver nitrate solution and incubated in dark in rotary shaker samples shows changed in colour from almost colourless to brown this is a clear indication of the formation of silvernanoparticles in the reaction mixture. The intensity of the colour was increased during the period of incubation. The appearance brown colour was due to the excitation of surface Plasmon vibrations.
Biosynthesis of silvernanoparticlesusingmarine sponge extract Haliclona was carried out. Marine sponges’ extracts are responsible for the reduction of silver nitrate solution. Silvernanoparticles synthesized using fresh and dry marine sponge. Experimental factors including, time duration, pH, temperature were optimized. Silvernanoparticles were characterized by UV- Visible spectrophotometry. The sizes of synthesis silvernanoparticles were 27-46 nm and confirmed by scanning electron microscopy (SEM). X-ray diffraction (XRD) crystallography indicated the silvernanoparticles crystalline nature. Fourier transform infrared spectroscopy (FT-IR) was revealed the functional groups of extract of Haliclona, which are capable of reduction of silvernanoparticles. This method is a cost-effective, eco-friendly and nontoxic procedure.
The freshly grown GGS was washed very well in tap water, shade dried, and powdered in a blender 50 g of sprout powder was mixed with methanol and stored inside the conical flask for 1 week. After 7 days, extract had been filtered with Whatman No. 1 filter paper. The filtrated methanol extracts are dried and used for GC-MS studies. GC-MS analysis was performed using Shimadzu QP 2010 plus mass analyzer. (injection mode: Normal, column oven temperature: 100°C, and injection temperature: 250°C). Each component was calculated by comparing the average peak area to the total area for relative peak area. The National Institute of Standards and Technology (NIST) database is used to identify >62,000 patterns of individual components. The unknown sample spectrum was compared with the spectrum of known component saved in the NIST library. The element name, shape, and molecular weight of the test sample had been ascertained.
The use of nanotechnology to synthesize compounds with improved anti microbial properties is an area of current research by many scientists. In our study, we report the non toxic, practical and environmentally benevolent approach for the synthesis of silvernanoparticlesusing the ethanolic extract of H. sinensis plant with potent anti microbial activity. The production of cytokines are key events in the regulation of an microbial response and recent attention has been focused on the effect of the synthesized nanoparticles as selective cytokine inhibitory agents 17 .
([SEM–EDS] JEOL-64000; JEOL, Tokyo, Japan). The surface morphology, crystalline nature, and size of the synthesized AgNPs were examined using high-resolution transmission electron microscopy ([TEM] JEM-2010; JEOL) at an accelerating voltage of 200 kV. The spectra of the AgNPs were obtained by Fourier transform infrared spectroscopy ([FTIR] PerkinElmer, Waltham, MA, USA) in the diffuse reflectance mode at a resolution of 4 cm -1
Our objective is the eco-friendly green synthesis of AgNPs using the M. pudica root extract. Its addition to the silver nitrate solution causes the change of the color of the reaction mixture from pale yellow to dark brown owing to the excitation of surface plasmon resonance (SPR) by AgNPs. Figure 1 shows UV-Vis Spectra at different reaction times. The sample exhibits an absorbance band at about 430 nm wavelength. As the reaction time increases, the absorbance peaks become sharper as shown in Figure 1(a) to (d). The increase in the intensity of peak could be due to increase in the number of Ag nanoparticles in the reaction medium. After reaching a particular intervals of time (i.e 60 minutes duration), the absorbance peak of Ag nanoparticles increases very slowly (nearly constant) as shown in the Figure 1(d). This is due to the reduction of all the Ag ions present in the reaction medium into Ag nanoparticles. In our experiments, the optimal reaction was found to be 60 minutes.
Nanoparticles possess a very high surface to Volume ratio exhibit greater specific surface areas and surface energies, quantum related effects etc (Dagani, 2002). To compete with this tremendous demand, the synthesis of nanomaterials of specific composition, shape and size is a burgeoning area of research in the field of nanotechnology. Nanotechnology is widely used in the fields like medicines, food, consumer products energy, health care, environment, agriculture etc. Nanoparticles possess increased structural integrity as well as unique chemical, optical, mechanical, electronic and magnetic properties compared to large particles of bulk materials. The main approaches for fabrication of nanoparticles are top-down and bottom- up approach. The sizes of nanostructures produced by this method are between 10 to 100 nm. All physical, chemical and biological method used for synthesis of nanoparticle comes under these approach. “Green nanotechnology” is defined as the environmentally friendly manufacturing processes that reduce waste products which ultimately lead to atomically precise molecular manufacturing with zero waste. Green nanotechnology is of prime importance because chemical synthesis is toxic and leads to by products that are not environmental benign. In green nanotechnology the nanoparticles are synthesized by various plant extract and microbes. Silver is a highly stable metal which has a wide range of application from ancient days. A variety of techniques have been developed to synthesize metal nanoparticles, including chemical reduction using a number of chemical reductants including tri sodium citrate, ethanol, ethylene glycol and N,N-dimethylformamide 1 , aerosol technique, electrochemical or sonochemical deposition photochemical reduction, and laser irradiation technique. 2 Silvernanoparticles are potent and broad- spectrum antibacterial agents with activity against diverse species within both Gram-positive and Gram-
In recent years, silvernanoparticles are widely applied in chemical industry as an additive to cosmetics, because silvernanoparticles satisfy the requirements of excel- lent antiseptic properties, as a safe preservative addi- tive, and also as a constituent for the skin therapy, e.g., treatment of acne (Kokura et al. 2010). In addition to the applications of silvernanoparticles in medical and envi- ronmental protection field, silver nanoparticle-coated paper could also serve a critical role in food preservation in which provides a reservoir for slow releasing of ionic silver from the surface to the bulk to prevent microbial growth in the food as well as to prevent growth of patho- gens on the surface itself (Gottesman et al. 2011). Owing to the excellent antimicrobial activity of silver nanopar- ticles, developing antibacterial coatings on surfaces has drawn much interest for human health and environmen- tal protection in the paint coating industry. In 2008, John et al. demonstrated green synthesis techniques of metallic nanoparticle-embedded paints using common household paint in a single step. Through the naturally occurring oxidative drying process in oils that involves free-radi- cal exchange, reduction of metal salts and dispersion of metal nanoparticles in the oil media were successfully done without the use of any external chemical reducing or stabilizing agents. The resulting well-dispersed metal nanoparticles in oil dispersions can then be directly used on different surfaces such as wood, glass, steel, and differ- ent polymer surfaces, and also exhibit excellent bacteri- cidal properties against gram-positive and gram-negative bacteria, especially silver nanoparticle-embedded paints (Kumar et al. 2008).
nanoparticles may have hostile effects in medical applica- tions. Thus, many of the latest antibacterial agents devel- oped in the last decades; none of them has been achieved its activity against multi-drug resistant bacteria [5, 7]. Newly, nanotechnology has very remarkable in the phar- maceutical and biomedical field as alternative antimicro- bial agent design in the view of the fact that renovation the occurrence and infective diseases of antibiotic- resistant strains, especially within gram-negative bacteria. Also, there is an increasing concern for silver nanoparti- cles on account of the antimicrobial properties . Sil- ver is a powerful inorganic antimicrobial agent, safe and non-toxic that is capable of killing about 600 types of diseases .
Silvernanoparticles (Ag NPs) have become important scopes of research because of their applications in scientific field. The present study made insight into the using of yeast as eco-friendly and low-cost source for biosynthesis of Ag NPs. Whereas 50 yeast isolates were tested for their abilities to synthesize Ag NPs. Characterization of the Ag NPs of the most promising yeast isolate AUN-S18 was performed using UV– Visible spectrophotometer, transmission electron microscopy. Ag NPs are spherical in shapes with size in the range of 9-35.5 nm. The produced Ag NPs showed antibacterial action against human and plant pathogens including, Staphylococcus aureus, Klebsiella pneumonia, Erwinia amylovora and Xauthonomas ceupestris pv.vesitcora with inhibition zone diameters ranged from 3.00 -13.00 mm.
ABSTRACT: In recent years metallic nanoparticles, represent one of the most comprehensively studied materials because of their application in biology The synthesis of silvernanoparticlesusing biological entities has received immense attention in the area of research. Medicinal plants have attracted interest over antibiotics due to a rapid increase in the rate of infections, development of antibiotic resistance in microorganisms and side effects of antibiotics. In the present study biosynthesis of silvernanoparticles was performed using Syzygium cumini. Spectrochemical studies indicate the surface plasmon resonance band and the presence of a capping agent responsible for the synthesis of AgNPs. The results revealed that S. cumini along with synthesized AgNP found to possess microbicidal effect. 400 µl of synthesized AgNP was found to be resistant against Bacillus sp. (23 mm), followed by S. epidermis and A. niger (22.5 mm). HPLC chromatogram reveals the presence of flavonoids such as quercetin and myricetin responsible for bioassay.
The use of marine red algae seaweed for the biosynthesis of silver nanoparticle is a viable method because of its eco friendly and low cost effectiveness. The biomolecules extracted from the alga H.poryphyroides finds its applications in the field of medical biochemistry. The present findings suggest that biosynthesized silvernanoparticles from H.poryphyroides effectively inhibit both α-amylase and α–glucosidase enzymes in vitro in a dose dependent manner which paves a way for the in vivo studies further. The synthesized silvernanoparticles proved to exhibit better antidiabetic efficacy against standard Acarbose. Therefore, green synthesis methods of silvernanoparticles are a good source of all these inhibitors and leading a pathway for further use of silvernanoparticles for pharmacological activities.
The present study of trustworthy processes for the synthesis of Nanosized materials is of countless importance in the field of nanotechnology. Biosynthesis of SilverNanoparticles (AgNPs) using bacteria has arriving weighty interest because of their potential to synthesize nanoparticles. In the current study, synthesis of silvernanoparticles by a bacterial strain (DA-12) isolated from soil is reported. The bacterium was isolated, screened and characterized by morphological, biochemical and 16S rRNA analyses. Molecular identification of the isolate was done which showed a strain is Bacillus shackletonii DA-12. When treating the isolated bacteria with 1mm Silver nitrate (AgNO 3 ), it was found to have the proficiency to form