Biosynthesis of Silver Nanoparticles by Streptomyces griseorubens isolated from Soil and Their Antioxidant Activity

Microbial mediated biological synthesis of metallic nanoparticles was carried out ecofriendly in the present study. Silver nanoparticles (AgNPs) were extracellularly biosynthesised from Streptomyces griseorubens AU2 and extensively characterised by ultraviolet–visible (UV–vis) and Fourier transform infrared spectroscopy, high‐resolution transmission electron microscopy, scanning electron microscopy and X‐ray diffraction analysis. Elemental analysis of nanoparticles was also carried out using energy dispersive X‐ray spectroscopy. The biosynthesised AgNPs showed the characteristic absorption spectra in UV–vis at 422 nm which confirmed the presence of metallic AgNPs. According to the further characterisation analysis, the biosynthesised AgNPs were found to be spherical and crystalline particles with 5–20 nm average size. Antioxidant properties of the biosynthesised AgNPs were determined by 2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging assay and was found to increase in a dose‐dependent matter. The identification of the strain was determined by molecular characterisation method using 16s rDNA sequencing. The present study is the first report on the microbial biosynthesis of AgNPs using S. griseorubens isolated from soil and provides that the active biological components found in the cell‐free culture supernatant of S. griseorubens AU2 enable the synthesis of AgNPs.Inspec keywords: silver, microorganisms, nanoparticles, nanofabrication, DNA, molecular biophysics, ultraviolet spectra, visible spectra, scanning electron microscopy, Fourier transform infrared spectra, transmission electron microscopy, X‐ray diffraction, X‐ray chemical analysis, absorption coefficients, cellular biophysicsOther keywords: silver nanoparticles, Streptomyces griseorubens AU2, soil, antioxidant activity, microbial mediated biological synthesis, ultraviolet‐visible spectroscopy, Fourier transform infrared spectroscopy, UV‐vis spectroscopy, high‐resolution transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, elemental analysis, energy dispersive X‐ray spectroscopy, absorption spectra, spherical particles, crystalline particles, 2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging assay, strain identification, molecular characterisation method, rDNA sequencing, active biological components, cell‐free culture supernatant, wavelength 422 nm, size 5 nm to 20 nm, Ag     

Silver nanoparticles biosynthesised using Centella asiatica leaf extract: apoptosis induction in MCF‐7 breast cancer cell line

The aim of this study was to green synthesised silver nanoparticles (AgNPs) using Centella asiatica leaf extract and investigate the cytotoxic and apoptosis‐inducing effects of these nanoparticles in MCF‐7 breast cancer cell line. The characteristics and morphology of the green synthesised AgNPs were evaluated using transmission electron microscopy, scanning electron microscopy, UV–visible spectroscopy, X‐ray diffraction, and Fourier‐transform infrared spectroscopy. The MTT assay was used to investigate the anti‐proliferative activity of biosynthesised nanoparticles in MCF‐7 cells. Apoptosis test was performed using flow cytometry and expression of caspase 3 and 9 genes. The spherical AgNPs with an average size of 19.17 nm were synthesised. The results showed that biosynthesised AgNPs exhibited cytotoxicity, anti‐cancer, apoptosis induction, and increased expression of genes encoding for caspases 3 and 9 in MCF‐7 cancer cells in a concentration‐ and time‐dependent manner. It seems that green synthesised AgNPs have potential uses for pharmaceutical industries.Inspec keywords: ultraviolet spectra, transmission electron microscopy, cellular biophysics, infrared spectra, visible spectra, nanofabrication, cancer, toxicology, nanomedicine, nanoparticles, biomedical materials, scanning electron microscopy, silver, Fourier transform spectra, X‐ray diffraction, genetics, enzymes, botany, biochemistryOther keywords: spherical AgNPs, biosynthesised AgNPs, anti‐cancer, apoptosis induction, green synthesised AgNPs, MCF‐7 breast cancer cell line, green synthesised silver nanoparticles, Ag, caspase gene expression, flow cytometry, anti‐proliferative activity, MTT assay, pharmaceutical industries, cytotoxicity, UV–visible spectroscopy, nanoparticle morphology, scanning electron microscopy, Centella asiatica leaf extract, biosynthesised nanoparticles, Fourier‐transform infrared spectroscopy, transmission electron microscopy     

Facile phyto‐mediated synthesis of silver nanoparticles using Chinese winter jujube (Ziziphus jujuba Mill. cv. Dongzao) extract and their antibacterial/catalytic properties

The aqueous extract of Chinese winter jujube (Ziziphus jujuba Mill. cv. Dongzao) was used as reducing and capping agents for the synthesis of silver nanoparticles (AgNPs) for the first time. The resulting AgNPs were characterised by UV/Visible (UV–Vis) spectroscopy, atomic force microscope, transmission electron microscopy, selected area electron diffraction, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray and Fourier transform infrared spectroscopy (FTIR). The colloidal solution of AgNPs gave a maximum UV–Vis absorbance at 446 nm. The synthesised nanoparticles were almost in the spherical shapes with an average size of 11.5 ± 4. 8 nm. FTIR spectra were applied to identify the functional groups which were possibly responsible for the conversion of metal ions into nanoparticles. The results showed that the prepared AgNPs were coated with the biomolecules in the extract. The biosynthesised AgNPs showed a remarkable catalytic activity at room temperature, and they also showed good antibacterial properties against Escherichia coli and Staphylococcus aureus.Inspec keywords: silver, nanoparticles, nanofabrication, antibacterial activity, biomedical materials, nanobiotechnology, scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, ultraviolet spectra, visible spectra, X‐ray chemical analysis, Fourier transform infrared spectra, catalysisOther keywords: wavelength 446 nm, temperature 293 K to 298 K, Ag, Escherichia coli, Staphylococcus aureus, biomolecules, catalytic activity, metal ions, colloidal solution, FTIR spectra, UV‐vis absorbance, TEM, SEM, XRD, Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, scanning electron microscopy, X‐ray diffraction, selected area electron diffraction, transmission electron microscopy, atomic force microscopy, UV‐visible spectroscopy, catalytic properties, antibacterial properties, Chinese winter jujube extract, silver nanoparticles, facile phyto‐mediated synthesis     

Antibacterial,anticancer and antioxidant potential of silver nanoparticles engineered using Trigonella foenum‐graecum seed extract

In this study, the authors report a simple and eco‐friendly method for the synthesis of silver nanoparticles (AgNPs) using Trigonella foenum‐graecum (TFG) seed extract. They explored several parameters dictating the biosynthesis of TFG‐AgNPs such as reaction time, temperature, concentration of AgNO₃, and TFG extract amount. Physicochemical characterisation of TFG‐AgNPs was done on dynamic light scattering (DLS), field emission electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. The size determination studies using DLS revealed of TFG‐AgNPs size between 95 and 110 nm. The antibacterial activity was studied against Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa and Staphylococcus aureus. The biosynthesised TFG‐AgNPs showed remarkable anticancer efficacy against skin cancer cell line, A431 and also exhibited significant antioxidant efficacy.Inspec keywords: antibacterial activity, cancer, biomedical materials, silver, nanofabrication, nanomedicine, nanoparticles, microorganisms, skin, cellular biophysics, biochemistry, light scattering, X‐ray chemical analysis, X‐ray diffraction, Fourier transform infrared spectra, particle sizeOther keywords: antibacterial potential, anticancer potential, antioxidant potential, silver nanoparticles, Trigonella foenum‐graecum seed extract, eco‐friendly method, biosynthesis, reaction time, AgNO₃ concentration, TFG extract amount, physicochemical characterisation, dynamic light scattering, field emission electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, size determination, TFG‐AgNPs size, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Staphylococcus aureus, skin cancer cell line A431, Ag     

One‐pot green synthesis and structural characterisation of silver nanoparticles using aqueous leaves extract of Carissa carandas : antioxidant,anticancer and antibacterial activities

Facile green synthesis of silver nanoparticles (AgNPs) using an aqueous extract of Carissa carandas (C. carandas) leaves was studied. Fabrication of AgNPs was confirmed by the UV–visible spectroscopy which gives absorption maxima at 420 nm. C. carandas leaves are the rich source of the bioactive molecules, acts as a reducing and stabilising agent in AgNPs, confirmed by Fourier transforms infrared spectroscopy. The field emission scanning electron microscope revealed the spherical shape of biosynthesised AgNPs. A distinctive peak of silver at 3 keV was determined by energy dispersive X‐ray spectroscopy. X‐ray diffraction showed the facecentred cubic structure of biosynthesised AgNPs and thermal stability was confirmed by the thermogravimetric analysis. Total flavonoid and total phenolic contents were evaluated in biosynthesised AgNPs. Biosynthesised AgNPs showed free radical scavenging activities against 2, 2‐diphenyl‐1‐picrylhydrazyl test and ferric reducing antioxidant power assay. In vitro cytotoxicity against hepatic cell lines (HUH‐7) and renal cell lines (HEK‐293) were also assessed. Finally, biosynthesised AgNPs were scrutinised for their antibacterial activity against methicillin‐resistant Staphylococcus aureus, Shigella sonnei, Shigella boydii and Salmonella typhimurium. This study demonstrated the biofabrication of AgNPs by using C. carandas leaves extract and a potential in vitro biological application as antioxidant, anticancer and antibacterial agents.Inspec keywords: antibacterial activity, biomedical materials, cancer, tumours, nanomedicine, silver, nanoparticles, reduction (chemical), nanofabrication, ultraviolet spectra, visible spectra, field emission scanning electron microscopy, Fourier transform infrared spectra, X‐ray chemical analysis, X‐ray diffraction, thermal stability, thermal analysis, free radical reactions, toxicology, cellular biophysics, microorganismsOther keywords: total phenolic contents, free radical scavenging activities, 2,2‐diphenyl‐1‐picrylhydrazyl test, ferric reducing antioxidant power assay, in vitro cytotoxicity, hepatic cell lines HUH‐7, renal cell lines HEK‐293, antibacterial activity, methicillin‐resistant Staphylococcus aureus, Shigella sonnei, Shigella boydii, Salmonella typhimurium, biofabrication, in vitro biological application, Ag, total flavonoid contents, thermogravimetric analysis, thermal stability, face‐centred cubic structure, X‐ray diffraction, energy dispersive X‐ray spectroscopy, distinctive peak, spherical shape, field emission scanning electron microscope, Fourier transforms infrared spectroscopy, stabilising agent, reducing agent, bioactive molecules, absorption maxima, UV‐visible spectroscopy, plant extract colour, antibacterial activities, anticancer activities, antioxidant activities, Carissa carandas, aqueous leaves extract, silver nanoparticles, structural characterisation, one‐pot green synthesis     

Postprandial anti‐hyperglycemic activity of marine Streptomyces coelicoflavus SRBVIT13 mediated gold nanoparticles in streptozotocin induced diabetic male albino Wister rats

The present study focuses on the biosynthesis of gold nanoparticles (AuNPs) using Streptomyces coelicoflavus (S. coelicoflavus) SRBVIT13 isolated from marine salt pan soils collected from Ongole, Andhra Pradesh, India. The biosynthesised AuNPs are characterised by UV–visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, high‐resolution transmission electron microscopy and energy‐dispersive X‐ray analysis. Transmission electron microscopy study suggests that the biosynthesised AuNPs are spherical in shape within a size range of 12–20 nm (mean diameter as 14 nm). The anti‐type II diabetes activity of AuNPs is carried out by testing it in vitro α ‐glucosidase and α ‐amylase enzyme inhibition activity and in vivo postprandial anti‐hyperglycemic activity in sucrose and glucose‐loaded streptozotocin induced diabetic albino Wister rats. AuNPs has shown a significant inhibitory activity of 84.70 and 87.82% with IC₅₀ values of 67.65 and 65.59 μg/mL to α ‐glucosidase and α ‐amylase enzymes, while the diabetic rats have shown significant reduction in the post postprandial blood glucose level by 57.80 and 88.09%, respectively compared with control group after AuNPs treatment at the concentration of 300 and 600 mg/kg body weight. Hence, this biosynthesised AuNPs might be useful in combating type II diabetes mellitus for the betterment of human life.Inspec keywords: gold, nanoparticles, ultraviolet spectra, visible spectra, X‐ray diffraction, Fourier transform infrared spectra, transmission electron microscopy, X‐ray chemical analysis, diseases, enzymes, nanomedicine, biochemistry, spectrochemical analysisOther keywords: gold nanoparticles, Streptomyces coelicoflavus SRBVIT13, biosynthesis, UV–visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, high‐resolution transmission electron microscopy, energy‐dispersive X‐ray analysis, antitype II diabetes activity, in vitro enzyme inhibition activity, in vivo postprandial antihyperglycemic activity, streptozotocin induced diabetic albino Wister rats, type II diabetes mellitus, Au     

Role of Ribes khorassanicum in the biosynthesis of AgNPs and their antibacterial properties

Silver nanoparticles (AgNPs) have been biosynthesised through the extracts of Ribes khorassanicum fruits, which served as the reducing agents and capping agents. Biosynthesised AgNPs have been found to be ultraviolet–visible (UV–vis) absorption spectra since they have displayed one surface plasmon resonance peak at 438 nm, attesting the formation of spherical NPs. These particles have been characterised by UV–vis, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy analysis. The formation of AgNPs at 1.0 mM concentration of AgNO₃ has resulted in NPs that contained mean diameters in a range of 20–40 nm. The green‐synthesised AgNPs have demonstrated high antibacterial effect against pathogenic bacteria (i.e. Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa). Biosynthesising metal NPs through plant extracts can serve as the facile and eco‐friendly alternative for chemical and/or physical methods that are utilised for large‐scale nanometal fabrication in various medical and industrial applications.Inspec keywords: X‐ray diffraction, X‐ray chemical analysis, nanofabrication, surface plasmon resonance, nanoparticles, antibacterial activity, microorganisms, scanning electron microscopy, silver, nanomedicine, visible spectra, ultraviolet spectra, transmission electron microscopy, Fourier transform infrared spectra, field emission scanning electron microscopy, biomedical materialsOther keywords: antibacterial properties, silver nanoparticles, reducing agents, capping agents, surface plasmon resonance peak, spherical NPs, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, transmission electron microscopy analysis, plant extracts, ultraviolet‐visible absorption spectra, Fourier transform infrared spectroscopy, antibacterial effect, Ribes khorassanicum fruits, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, surface plasmon resonance, AgNO₃ , Ag     

Green synthesis of nanosilver‐decorated graphene oxide sheets

A green facile method has been successfully used for the synthesis of graphene oxide sheets decorated with silver nanoparticles (rGO/AgNPs), employing graphite oxide as a precursor of graphene oxide (GO), AgNO₃ as a precursor of Ag nanoparticles (AgNPs), and geranium (Pelargonium graveolens) extract as reducing agent. Synthesis was accomplished using the weight ratios 1:1 and 1:3 GO/Ag, respectively. The synthesised nanocomposites were characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, UV‐visible spectroscopy, Raman spectroscopy, energy dispersive X‐ray spectroscopy and thermogravimetric analysis. The results show a more uniform and homogeneous distribution of AgNPs on the surface of the GO sheets with the weight ratio 1:1 in comparison with the ratio 1:3. This eco‐friendly method provides a rGO/AgNPs nanocomposite with promising applications, such as surface enhanced Raman scattering, catalysis, biomedical material and antibacterial agent.Inspec keywords: silver, nanoparticles, graphene, nanocomposites, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, ultraviolet spectra, visible spectra, X‐ray chemical analysis, surface enhanced Raman scattering, catalysis, nanofabricationOther keywords: antibacterial agent, biomedical material, catalysis, surface enhanced Raman scattering, rGO‐AgNP nanocomposite, eco‐friendly method, homogeneous distribution, thermogravimetric analysis, energy dispersive X‐ray spectroscopy, Raman spectroscopy, UV‐visible spectroscopy, X‐ray diffraction, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, nanocomposites, reducing agent, geranium, graphene oxide sheets, graphite oxide, silver nanoparticles, green facile method     

Sunlight induced biosynthesis of silver nanoparticle from the bark extract of Amentotaxus assamica D.K. Ferguson and its antibacterial activity against Escherichia coli and Staphylococcus aureus

Green synthesis of nanoparticles has gained importance due to its eco‐friendly, low toxicity and cost effective nature. This study deals with the biosynthesis of silver nanoparticles (AgNPs) from the bark extract of Amentotaxus assamica. The AgNPs have been synthesised by reducing the silver ions into stable AgNPs using the bark extract of Amentotaxus assamica under the influence of sunlight irradiation. The characterisation of the biosynthesised AgNPs was carried out by UV–vis spectroscopy, X‐ray diffraction analysis (XRD), Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and energy dispersive X‐ray analysis. The UV–vis spectrum showed a broad peak at 472 nm. Also, the XRD confirmed the crystalline structure of the AgNPs. Moreover, the SEM analysis revealed that the biosynthesised AgNPs were spherical in shape. Also, dynamic light scattering techniques were used to evaluate the size distribution profile of the biosynthesised AgNPs. Furthermore, the biosynthesised AgNPs showed a prominent inhibitory effect against both Escherichia coli (MTCC 111) and Staphylococcus aureus (MTCC 97). Thus the biosynthesis of AgNPs from the bark extract of Amentotaxus assamica is found to eco‐friendly way of producing AgNPs compared to chemical method.Inspec keywords: X‐ray chemical analysis, microorganisms, transmission electron microscopy, nanoparticles, toxicology, scanning electron microscopy, ultraviolet spectra, particle size, Fourier transform spectra, X‐ray diffraction, antibacterial activity, visible spectra, infrared spectra, nanomedicine, silverOther keywords: stable AgNP, biosynthesised AgNP, SEM analysis, sunlight irradiation, silver ions, silver nanoparticle, amentotaxus assamica, biosynthesis, escherichia coli     

Biosynthesis of Selenium Nanoparticles using yeast Nematospora coryli and examination of their anti‐candida and anti‐oxidant activities

Selenium (Se) is a rare and essential element for the human body and other living organisms because of its role in the structure of several proteins and having anti‐oxidant properties to reduce oxidative stress at cells. Some microorganisms can absorb Se oxyanions and convert them into zero‐valent Se (Se0) in the nanoscale dimensions, which can be used for producing Se nanoparticles (SeNPs). In the present study, SeNPs were intracellularly biosynthesised by yeast Nematospora coryli, which is an inexpensive method and does not involve using materials hazardous for human and environment. The produced NPs were refined by a two‐phase system and then characterised and identified by ultraviolet–visible, X‐ray diffraction, X‐ray fluorescence, transmission electron microscope, and Fourier transform infrared spectroscopy analyses. The structural analysis of biosynthesised SeNPs showed spherical‐shaped NPs with size ranging from 50 to 250 nm. Also, extracted NPs were applied to explore their anti‐candida and anti‐oxidant activities. The results of this investigation confirm the biological properties of Se.Inspec keywords: X‐ray diffraction, microorganisms, oxidation, transmission electron microscopy, reduction (chemical), nanomedicine, biomedical materials, visible spectra, nanoparticles, proteins, nanofabrication, selenium, ultraviolet spectra, particle size, Fourier transform infrared spectra, antibacterial activityOther keywords: proteins, oxidative stress, Se oxyanions, yeast, biosynthesised SeNPs, anti‐oxidant activities, human body, living organisms, Se nanoparticles, Nematospora coryli, anti‐candida activities, biosynthesis, ultraviolet–visible analysis, X‐ray diffraction, X‐ray fluorescence, transmission electron microscope, Fourier transform infrared spectroscopy, structural analysis, size 50.0 nm to 250.0 nm, Se     

Biosynthesis of the CuO nanoparticles using Euphorbia Chamaesyce leaf extract and investigation of their catalytic activity for the reduction of 4‐nitrophenol

Through this study an eco‐friendly, simple, efficient, cheap and biocompatible approach to the biosynthesis and stabilisation of CuO nanoparticles (NPs) using the Euphorbia Chamaesyce leaf extract is presented. The CuO NPs were monitored and characterised by field emission scanning electron microscopy, energy dispersive X‐ray spectroscopy, Fourier transformed infrared spectroscopy, transmission electron microscope and UV‐visible spectroscopy. The biosynthesised CuO NPs showed good catalytic activity for the reduction of 4‐nitrophenol (4‐NP) in water during 180 s and reused 4 times without considerable loss of activity.Inspec keywords: copper compounds, nanoparticles, nanofabrication, catalysis, reduction (chemical), field emission electron microscopy, X‐ray chemical analysis, Fourier transform infrared spectra, transmission electron microscopy, ultraviolet spectra, visible spectraOther keywords: biosynthesis, CuO nanoparticles, Euphorbia Chamaesyce leaf extract, catalytic activity, 4‐nitrophenol reduction, nanoparticle stabilisation, field emission scanning electron microscopy, energy dispersive X‐ray spectroscopy, Fourier transformed infrared spectroscopy, transmission electron microscope, UV‐visible spectroscopy, CuO     

Phytofabrication of silver nanoparticles using Bacopa monnieri leaf extract and its antibacterial activity as well as oxidative stress‐induced apoptosis of lung cancer

The biological method for synthesis of silver nanoparticles (AgNPs) using Bacopa monneri leaves and its anti‐proliferation against human lung adenocarcinoma cell line (A549) was studied. The AgNPs synthesis was determined by an ultraviolet–visible spectrum and was confirmed primarily by the colour change and surface plasmon resonance was observed at 450 nm and its reduction of functional groups stretched in AgNPs was identified by Fourier transform infrared and the crystalline nature of AgNPs was confirmed by X‐ray diffraction. The structural morphology of the AgNPs was found to be spherical and polygonal shape and size (> 35 nm) were determined by field emission scanning electron microscopy analysis and its purity was identified by energy dispersive analysis of X‐rays (EDAX). A further, antibacterial activity of biosynthesised AgNPs against Gram negative and Gram positive bacteria was assessed. The cytotoxic effect of synthesised AgNPs was analysed against human lung adenocarcinoma cells by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. The GI₅₀ was found to be 20 µg/ml at 24 h incubation. The apoptosis cells containing condensate and marginalised chromatin stages were analysed by propidium iodide staining and DNA damage was observed in A549 treated cells. The present study strongly emphasised that the bioactive molecule‐coated AgNPs could have potential for biomedical applications and significant anticancer effects against human lung adenocarcinoma cells.Inspec keywords: antibacterial activity, biomedical materials, lung, cancer, oxidation, nanoparticles, silver, nanofabrication, nanomedicine, cellular biophysics, ultraviolet spectra, visible spectra, surface plasmon resonance, Fourier transform infrared spectra, X‐ray diffraction, particle size, field emission electron microscopy, scanning electron microscopy, X‐ray chemical analysis, microorganisms, toxicology, DNA, molecular biophysics, molecular configurationsOther keywords: silver nanoparticles, phytofabrication, Bacopa monnieri leaf extract, antibacterial activity, oxidative stress‐induced apoptosis, biological method, antiproliferation, human lung adenocarcinoma cell line A549, AgNPs synthesis, ultraviolet‐visible spectrum, colour change, surface plasmon resonance, stretched functional groups, Fourier transform infrared spectra, crystalline nature, X‐ray diffraction, geometric spherical shape, polygonal shape, field emission scanning electron microscopy analysis, EDAX, biosynthesised AgNPs, gram negative bacteria, gram positive bacteria, cytotoxic effect, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay, incubation, apoptosis cells, condensate, marginalised chromatin stages, propidium iodide staining, DNA damage, A549 treated cells, bioactive molecule‐coated AgNPs, biomedical applications, anticancer effects, time 24 h, Ag     

Green synthesis and evaluation of silver nanoparticles for antimicrobial and biochemical profiling in Kinnow (Citrus reticulata L.) to enhance fruit quality and productivity under biotic stress

Green synthesis of silver nanoparticles (AgNPs) by utilising plant extract is an emerging class of nanotechnology. It revolutionizes all the field of biological sciences by synthesizing chemical free AgNPs. In the present study, AgNPs were synthesised by utilising Moringa oleifera leaves as the main reducing and stabilising agent and characterised through UV–visible spectroscopy, zeta analyser, X‐ray diffraction spectroscopy (XRD), energy dispersive X‐ray (EDX), and scanning electron microscopy (SEM). The different concentrations of biosynthesised AgNPs (10, 20, 30, and 40 ppm) were exogenously applied on the already infected plants (canker) of Citrus reticulata at different day intervals. The AgNPs at a concentration of 30 ppm was found to be most suitable concentration for creating the resistance against canker disease in Citrus reticulata. The enzymatic activities were also explored and it was found that 30 ppm concentration of biosynthesised AgNPs significantly reduced the biotic stress. Fruit quality and productivity parameters were also assessed and it was found that fruit quality and productivity were significant in response to 30 ppm concentration of biosynthesised AgNPs. The present work highlights the potent role of biosynthesised AgNPs, which can be used as biological control of citrus diseases and ultimately improving the quality and productivity of Citrus.Inspec keywords: X‐ray diffraction, scanning electron microscopy, silver, X‐ray chemical analysis, biochemistry, ultraviolet spectra, atomic force microscopy, visible spectra, biotechnology, microorganisms, nanoparticles, antibacterial activity, enzymes, nanotechnology, electrokinetic effects, plant diseases, crops, product qualityOther keywords: green synthesis, silver nanoparticles, fruit quality, chemical‐free AgNP synthesis, antimicrobial activity, biochemical profiling, Citrus reticulata L, Kinnow productivity, nanotechnology, Moringa oleifera leaves, stabilising agent, UV–Visible spectroscopy, zeta analyser, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, scanning electron microscopy, atomic force microscopy, Xanthomonas axonopodis, canker disease, enzymatic activities, superoxide dismutase, peroxidase, catalase, biological control, Ag     

Green‐route mediated synthesis of silver nanoparticles (AgNPs) from Syzygium cumini (L.) Skeels polyphenolic‐rich leaf extracts and investigation of their antimicrobial activity

Medicinal plants are widely utilised by the African population since they have no harmful side effects and low cost compared with different treatments. The field of nanotechnology is the most active part of research in modern material''s science. Though there are several chemicals as well as physical methods, however, green synthesis of nanomaterials is the most emerging method of synthesis. Conventionally, chemical reduction is the most often applied approach for the preparation of metallic nanoparticle''s however, in most of the synthesis protocols it cannot avoid the utilisation of toxic chemicals. Hence, the authors report an environmentally friendly, cost effective and green approach for synthesis of 1 mM AgNO₃ solution using the polyphenolic‐rich leaf extracts of Syzygium cumini (S. cumini) (L.) Skeels as a reducing and capping agent. The synthesised AgNPs are characterised by UV‐Vis spectroscopy and Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed that the AgNPs were stable due to eugenols, terpenes, and other different aromatic compounds present in the extract. The green biosynthesised S. cumini AgNPs significantly inhibited the growth of human pathogenic both gram‐positive Staphylococcus aureus (1.40 mm) and gram‐negative bacteria Escherichia coli (2.75 mm) and Salmonella typhimurium (1.45 mm) showing promising antimicrobial activity.Inspec keywords: silver, nanoparticles, nanofabrication, nanomedicine, antibacterial activity, biomedical materials, visible spectra, ultraviolet spectra, Fourier transform infrared spectra, microorganismsOther keywords: green‐route mediated synthesis, silver nanoparticles, Syzygium cumini, Skeels polyphenolic‐rich leaf extracts, antimicrobial activity, medicinal plants, African population, nanotechnology, physical methods, nanomaterials, metallic nanoparticles, AgNO₃ solution, polyphenolic‐rich leaf extracts, capping agent, UV‐visible spectroscopy, Fourier transform infrared spectroscopy, FTIR, eugenols, terpenes, aromatic compounds, green biosynthesis, human pathogenic growth, gram‐positive Staphylococcus aureus, gram‐negative bacteria Escherichia coli, Salmonella typhimurium, antimicrobial activity, size 2.75 mm, size 1.45 mm, size 1.40 mm, Ag     

Efficacy of mycosynthesised AgNPs from Earliella scabrosa as an in vitro antibacterial and wound healing agent

The silver nanoparticles (AgNPs) with their unique chemical and physical properties are proving as a new therapeutical agent. In the present study, the AgNPs synthesised from an aqueous extract of a macrofungus, Earliella scabrosa, were characterised by field emission scanning electron microscopy (FESEM), energy dispersive X‐ray analysis (EDX), high‐resolution transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and further evaluate for its in vitro antibacterial and wound healing efficacy. The mycosynthesised AgNPs exhibited the surface plasmon resonance peak at 410 nm with good stability over a period of a month. The FESEM and EDX analyses revealed the spherical‐shaped AgNPs of an average size of 20 nm and the presence of elemental Ag, respectively. The XRD pattern showed the crystalline nature of AgNPs. The FTIR spectra confirmed the conversion of Ag⁺ ions to AgNPs due to reduction by biomolecules of macrofungus extract. The mycosynthesised AgNPs showed effective antibacterial activity against two Gram‐positive bacteria, namely Bacillus subtilis and Staphylococcus aureus, and two Gram‐negative bacteria Escherichia coli and Pseudomonas aeruginosa. The pathogens were highly sensitive to AgNPs, whereas less sensitive to AgNO₃. The mycosynthesised AgNPs showed significant wound healing potential with 68.58% of wound closure.Inspec keywords: surface plasmon resonance, wounds, X‐ray diffraction, nanoparticles, molecular biophysics, nanomedicine, antibacterial activity, biomedical materials, reduction (chemical), silver, microorganisms, X‐ray chemical analysis, nanofabrication, transmission electron microscopy, particle size, field emission scanning electron microscopy, Fourier transform infrared spectraOther keywords: high‐resolution transmission electron microscopy, healing efficacy, mycosynthesised AgNPs, spherical‐shaped AgNPs, wound healing agent, in vitro antibacterial efficacy, Earliella scabrosa, silver nanoparticles, physical properties, chemical properties, therapeutical agent, aqueous extract, macrofungus, field emission scanning electron microscopy, FESEM, energy dispersive X‐ray analysis, EDX, X‐ray diffraction, XRD, Fourier transform infrared spectroscopy, FTIR spectroscopy, surface plasmon resonance peak, crystalline nature, biomolecules, Gram‐positive bacteria, Bacillus subtilis, Staphylococcus aureus, Gram‐negative bacteria, Escherichia coli, Pseudomonas aeruginosa, pathogens, wound closure, Ag     

Biosynthesised silver nanoparticles using aqueous leaf extract of Tagetes patula L. and evaluation of their antifungal activity against phytopathogenic fungi

In the recent decades, nanotechnology is gaining tremendous impetus due to its capability of modulating metals into their nanosize, which drastically changes the chemical, physical, biological and optical properties of metals. In this study, silver nanoparticles (AgNPs) synthesis using aqueous leaf extracts of Tagetes patula L. which act as reducing agent as well as capping agent is reported. Synthesis of AgNPs was observed at different parameters like temperature, concentration of silver nitrate, leaf extract concentration and time of reduction. The AgNPs were characterized using UV‐vis spectroscopy, scanning electron microscope with energy dispersive spectroscopy, transmission electron microscopy with selected area electron diffraction, X‐ray diffraction, Fourier transform infrared and dynamic light scattering analysis. These analyses revealed the size of nanoparticles ranging from 15 to 30 nm as well revealed their spherical shape and cubic and hexagonal lattice structure. The lower zeta potential (−14.2mV) and the FTIR spectra indicate that the synthesized AgNPs are remarkably stable for a long period due to the capped biomolecules on the surface of nanoparticles. Furthermore, these AgNPs were found to be highly toxic against phytopathogenic fungi Colletotrichum chlorophyti by both in vitro and in vivo and might be a safer alternative to chemical fungicides.Inspec keywords: silver, nanoparticles, nanofabrication, nanobiotechnology, ultraviolet spectra, visible spectra, scanning electron microscopy, X‐ray chemical analysis, electron diffraction, X‐ray diffraction, Fourier transform infrared spectra, crystal structure, electrokinetic effects, antibacterial activityOther keywords: biosynthesised silver nanoparticles, aqueous leaf extract, Tagetes patula L, antifungal activity, phytopathogenic fungi, nanotechnology, UV–vis spectroscopy, scanning electron microscope, energy dispersive spectroscopy, transmission electron microscopy, selected area electron diffraction, X‐ray diffraction, Fourier transform infrared spectra, dynamic light scattering analysis, hexagonal lattice structure, zeta potential, phytopathogenic fungi Colletotrichum chlorophyti, cubic lattice structure, size 15 nm to 30 nm, Ag     

Antioxidant,antibacterial and anticancer properties of phyto ‐ synthesised Artemisia quttensis Podlech extract mediated AgNPs

The focus of this study is on a rapid and cost‐effective approach for the synthesis of silver nanoparticles (AgNPs) using Artemisia quttensis Podlech aerial parts extract and assessment of their antioxidant, antibacterial and anticancer activities. The prepared AgNPs were determined by ultraviolet–visible spectroscopy, X‐ray diffraction, Fourier transform infra‐red spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, and dynamic light scattering and zeta‐potential analysis. The AgNPs and A. quttensis extract were evaluated for their antiradical scavenging activity by 2, 2‐diphenyl, 1‐picryl hydrazyl assay and anticancer activity against colon cancer (human colorectal adenocarcinoma cell line 29) compared with normal human embryonic kidney (HEK293) cells. Also, the prepared AgNPs were studied for its antibacterial activity. The AgNPs revealed a higher antioxidant activity compared with A. quttensis extract alone. The phyto‐synthesised AgNPs and A. quttensis extract showed a dose–response cytotoxicity effect against HT29 and HEK293 cells. As evidenced by Annexin V/propidium iodide staining, the number of apoptotic HT29 cells was significantly enhanced, following treatment with AgNPs as compared with untreated cells. Besides, the antibacterial property of the AgNPs indicated a significant effect against the selected pathogenic bacteria. These present obtained results show the potential applications of phyto‐synthesised AgNPs using A. quttensis aerial parts extract.Inspec keywords: nanoparticles, silver, nanomedicine, cancer, transmission electron microscopy, ultraviolet spectroscopy, visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, electrokinetic effects, kidney, cellular biophysics, antibacterial activity, toxicology, patient treatmentOther keywords: anticancer properties, antibacterial properties, antioxidant properties, phytosynthesised Artemisia quttensis Podlech extract mediated AgNP, ultraviolet‐visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, dynamic light scattering, zeta‐potential analysis, antiradical scavenging activity, 2,2‐diphenyl, 1‐picryl hydrazyl assay, anticancer activity, HT29 colon cancer, human embryonic kidney cells, HEK293 cells, A. quttensis extract, dose‐response cytotoxicity effect, Annexin V staining, apoptotic HT29 cells, pathogenic bacteria, propidium iodide staining, Ag     

Phyto‐mediated synthesis,biological and catalytic activity studies of gold nanoparticles

In the present study, a phyto‐mediated synthesis of gold nanoparticles (AuNPs) using an isoflavone, Dalspinosin (5,7‐dihydroxy‐6,3′,4′‐trimethoxy isoflavone) isolated from the alcoholic extract of roots of Dalbergia coromandeliana is reported. It is observed that Dalspinosin itself acts both as a reducing and a capping agent in the synthesis of the nanoparticles (NPs). An ultraviolet–visible (UV–Vis) spectral study showed a surface plasmon resonance band at 526 nm confirming the formation of AuNPs. The NPs formed were characterised by UV–Vis spectroscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HR‐TEM) with energy‐dispersive x‐ray spectroscopy (EDX) and dynamic light scattering. HR‐TEM analysis showed the synthesised AuNPs were spherical in shape with a size of 7.5 nm. The AuNPs were found to be stable for seven months when tested by in vitro methods showed good antioxidant and anti‐inflammatory activities. They also showed moderate anti‐microbial activities when tested against Gram positive (Staphylococcus aureus and Streptococcus sp), Gram negative bacterial strains (Klebsiella pneumonia and Klebsiella terrigena) and fungal strain (Candida glabrata). The biosynthesised AuNPs showed significant catalytic activity in the reduction of methylene blue with NaBH₄ to leucomethylene blue.Inspec keywords: biomedical materials, catalysis, Fourier transform infrared spectra, gold, light scattering, microorganisms, nanomedicine, nanoparticles, spectrochemical analysis, surface plasmon resonance, transmission electron microscopy, ultraviolet spectra, visible spectra, X‐ray chemical analysis, X‐ray diffractionOther keywords: phyto‐mediated synthesis, biological activity studies, catalytic activity studies, dalspinosin (5,7‐dihydroxy‐6,3′,4′‐trimethoxy isoflavone), alcoholic extract, roots, Dalbergia coromandeliana, ultraviolet‐visible spectral study, surface plasmon resonance band, UV‐Vis spectroscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction, high‐resolution transmission electron microscopy, EDX analysis, dynamic light scattering, HR‐TEM analysis, antioxidant activities, antiinflammatory activities, antimicrobial activities, Gram positive bacterial strains, Staphylococcus aureus, Streptococcus sp, Gram negative bacterial strains, wavelength 526 nm, size 7.5 nm, time 7 month, Au     

Enhanced cytotoxic activity of AgNPs on retinoblastoma Y79 cell lines synthesised using marine seaweed Turbinaria ornata

Retinoblastoma is the most common intraocular malignancy basically occurs among children below five. Certain ocular treatments such as surgery, radiation therapy and chemotherapy are more likely to cause side effects. Here, a rapid method of synthesising silver nanoparticles (AgNPs) from the brown seaweed Turbinaria ornata and its cytotoxic efficacy against the retinoblastoma Y79 cell lines was studied. The AgNPs synthesis was determined by Ultraviolet–visible spectroscopy and was further characterised by X‐ray diffraction, High‐resolution transmission electron microscopy, zeta potential, Energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis, Fourier transform infrared spectrum and inductively coupled plasma‐mass spectroscopy techniques. The synthesised AgNPs were found to be very stable and finely dispersed. The total phenolic content of the synthesised AgNPs was estimated at 43±2.52 mg/g gallic acid equivalent and the nanoparticles exhibited good scavenging activity analysed by 2, 2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulphonic acid) assay. Moreover, cytotoxicity of synthesised AgNPs against in vitro retinoblastoma Y79 cell lines showed a dose‐dependent response with an inhibitory concentration (IC₅₀) of 10.5 µg/mL. These results suggest that AgNPs could be a promising anticancer agent with enhanced activity in ocular treatment.Inspec keywords: toxicology, silver, nanoparticles, cellular biophysics, cancer, nanomedicine, nanofabrication, X‐ray diffraction, transmission electron microscopy, electrokinetic effects, X‐ray chemical analysis, thermal analysis, Fourier transform infrared spectra, ultraviolet spectra, visible spectra, biomedical materials, mass spectroscopic chemical analysisOther keywords: cytotoxic activity, marine seaweed Turbinaria ornata, intraocular malignancy, silver nanoparticles, brown seaweed Turbinaria ornata, X‐ray diffraction, high‐resolution transmission electron microscopy, zeta potential, EDAX, thermogravimetric analysis, Fourier transform infrared spectrum, inductively coupled plasma‐mass spectroscopy, phenolic content, gallic acid, scavenging activity, in vitro retinoblastoma Y79 cell lines, dose‐dependent response, inhibitory concentration, anticancer agent, 2,2′‐azinobis‐(3‐ethylbenzothiazoline‐6‐sulphonic acid) assay, nanotechnology‐based cancer diagnosis, ocular tumour treatment, ultraviolet‐visible spectroscopy, Ag     

Synthesis,characterisation and potential applications of polyaniline/chitosan‐Ag‐nano‐biocomposite

Biodegradable polymers have greatly promoted the development of environmental, biomedical and allied sciences because of their biocompatibility and doping chemistry. The emergence of nanotechnology has envisaged greater options for the development of biodegradable materials. Polyaniline grafted chitosan (i.e. biodegradable PANI) copolymer was prepared by the chemical in situ polymerisation of aniline using ammonium per sulphate as initiator while Ag nanoparticle were synthesised by chemical reduction method and incorporated in to the polymer matrix. The as prepared materials were characterised by X‐ray diffraction, Fourier transform Infra‐red spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis. Moreover energy storage capacity, impedance properties were also studied. The main focus was on the photocatalytic degradation of organic dyes to remove the toxic and carcinogenic pollutants. This polymer nano‐biocomposite has multifold applications and can be used as excellent materials for enhanced photodegradation and removal of toxic contaminants from waste waters and natural water streams. In addition, the biocompatible materials with excellent mechanical properties and low toxicity can also be used for tissue engineering, drug delivery and electrical energy storage devices.Inspec keywords: silver, filled polymers, polymer blends, nanocomposites, nanoparticles, nanofabrication, biodegradable materials, polymerisation, reduction (chemical), Fourier transform infrared spectra, transmission electron microscopy, X‐ray chemical analysis, X‐ray diffractionOther keywords: polyaniline‐chitosan‐silver‐nanobiocomposite, biodegradable polymers, biocompatibility, doping chemistry, nanotechnology, biodegradable PANI, polyaniline grafted chitosan copolymer, biodegradable materials, chemical in situ polymerisation, nanoparticle, polymer matrix, chemical reduction method, Fourier transform Infrared spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis, X‐ray diffraction, energy storage capacity, impedance properties, carcinogenic pollutants, toxic pollutants, photodegradation, toxic contaminants, natural water streams, waste waters, drug delivery, tissue engineering, electrical energy storage devices, mechanical properties, Ag