Rapid synthesis of Bi 2 O 3 nano‐needles via ‘green route’ and evaluation of its anti‐fungal activity

Here, the authors report a rapid, simple, and eco‐friendly process for synthesis of Bi₂ O₃ nano‐needles. Dioscorea alata tuber extract was used as both reducing and capping agent for the first time. These nanoparticles were characterised by X‐ray diffraction, field emission scanning electron microscope, and Fourier transform infrared (FTIR) spectrometry, the nano‐structured Bi₂ O₃ needles have an average diameter of 158 nm with the lengths in the range of 1–3 μm. CLSI M27‐A2 standard was followed for evaluation of anti‐fungal activity. Bi₂ O₃ nano‐needles show remarkable activity against Candida albicans. It exhibits four time greater activity than bulk Bi₂ O₃ powder and two time greater activity than itraconazole, which makes it a potent anti‐fungal drug.Inspec keywords: bismuth compounds, nanoparticles, X‐ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectra, drugs, nanomedicine, biomedical materials, nanofabricationOther keywords: nanoneedles, antifungal activity, nanoparticles, X‐ray diffraction, field emission scanning electron microscope, Fourier transform infrared spectrometry, CLSI M27‐A2 standard, Candida albicans, itraconazole, antifungal drug, Bi₂ O₃      

Biogenic synthesis of Au,Ag and Au–Ag alloy nanoparticles using Cannabis sativa leaf extract

Biogenic synthesis of gold (Au), silver (Ag) and bimetallic alloy Au–Ag nanoparticles (NPs) from aqueous solutions using Cannabis sativa as reducing and stabilising agent has been presented in this report. Formation of NPs was monitored using UV–visible spectroscopy. Morphology of the synthesised metallic and bimetallic NPs was investigated using X‐ray diffraction and scanning electron microscopy. Elemental composition and the surface chemical state of NPs were confirmed by energy dispersive X‐ray spectroscopy analysis. Fourier transform‐infrared spectroscopy was utilised to identify the possible biomolecules responsible for the reduction and stabilisation of the NPs. Biological applicability of biosynthesised NPs was tested against five bacterial strains namely Klebsiella pneumonia, Bacillus subtilis (B. subtilis), Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa (P. aeruginosa) and Leishmania major promastigotes. The results showed considerable antibacterial and anti‐leishmanial activity. The Au–Ag bimetallic NPs showed improved antibacterial activity against B. subtilis and P. aeruginosa as compared to Au and Ag alone, while maximum anti‐leishmanial activity was observed at 250 μg ml⁻¹ NP concentration. These results suggest that biosynthesised NPs can be used as potent antibiotic and anti‐leishmanial agents.Inspec keywords: silver, silver alloys, gold, gold alloys, nanoparticles, nanofabrication, reduction (chemical), ultraviolet spectra, visible spectra, X‐ray diffraction, scanning electron microscopy, X‐ray chemical analysis, Fourier transform infrared spectra, microorganisms, antibacterial activityOther keywords: biogenic synthesis, Cannabis sativa leaf extract, bimetallic alloy Au–Ag nanoparticles, aqueous solutions, reducing agent, stabilising agent, UV–visible spectroscopy, X‐ray diffraction, scanning electron microscopy, elemental composition, surface chemical state, energy dispersive X‐ray spectroscopy analysis, Fourier transform‐infrared spectroscopy, biomolecules, bacterial strains, Klebsiella pneumonia, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Leishmania major promastigotes, antibacterial activity, anti‐leishmanial activity, Ag, Au, AuAg     

Biosynthesis of silver and gold nanoparticles using Trichoderma atroviride for the biological control of Phomopsis canker disease in tea plants

The biological way of metallic nanoparticles production using ecofriendly biocontrol agents are largely used to control many plant pathogenic microorganisms in agriculture. Hence, an attempt was made to evaluate the potential of suppressive activity of nanoparticles produced by an indigenous isolate, Trichoderma atroviride against a tea pathogenic fungus namely Phomopsis theae. The presence of biosynthesised nanoparticles was primarily confirmed through ultraviolet–visible spectroscopy analysis and was characterised using X‐ray diffraction and scanning electron microscopy‐energy dispersive X‐ray analysis to delineate the size, shape and nature of particles. Further, Fourier transform infrared analysis revealed the functional biomolecules responsible for capping and stabilisation of nanoparticles. In addition, culture filtrate containing nanoparticles was subjected to invitro antifungal studies which revealed a considerable suppression on the growth of P. theae. The biosynthesised nanoparticles were found to be active even after 3 months which established and confirmed the stability. Finally, field experiments conducted with soil application and wound dressing of nanoparticles exhibited a significant reduction in canker size when plants treated with gold followed by silver nanoparticles. Similarly, improvement in leaf yield was noted in response to these treatments. The above study confirmed the efficacy of metallic nanoparticles in management of stem disease in tea plantation.Inspec keywords: diseases, gold, silver, nanoparticles, nanobiotechnology, nanofabrication, particle size, X‐ray diffraction, scanning electron microscopy, X‐ray chemical analysis, ultraviolet spectra, visible spectra, microorganisms, Fourier transform infrared spectra, molecular biophysics, antibacterial activityOther keywords: biosynthesis, silver nanoparticles, gold nanoparticles, Trichoderma atroviride, biological control, Phomopsis canker disease, tea plants, metallic nanoparticles, ecofriendly biocontrol agents, plant pathogenic microorganisms, agriculture, indigenous isolate, tea pathogenic fungus, Phomopsis theae, ultraviolet‐visible spectroscopy, X‐ray diffraction, scanning electron microscopy, energy dispersive X‐ray analysis, particle size, particle shape, Fourier transform infrared analysis, functional biomolecules, invitro antifungal study, P. theae growth, soil application, wound dressing, stem disease, Au, Ag     

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     

Cytotoxicity,leishmanicidal, and antioxidant activity of biosynthesised zinc sulphide nanoparticles using Phoenix dactylifera

The synthesis of zinc sulphide nanoparticles (ZnS NPs) using a green approach was explored. The resulting nanoparticles (NPs) were characterised by UV–vis spectroscopy, scanning and transmission electron microscopy, X‐ray diffraction and Fourier transform infrared spectroscopy. The leishmanicidal, cytotoxic and antioxidant activity of the resulting synthesised ZnS NPs (<70 nm) were evaluated against Leishmania major (L. major) promastigotes and amastigotes by MTT assay and using a macrophage model. The ZnS NPs were able to counteract the effects of oxidative metabolites as demonstrated by the oxidant activity. The IC₅₀ value of butylated hydroxyanisole was 26.04 µg/ml as compared with the IC₅₀ for ZnS NPs (90.95 µg/ml). The NPs displayed no cytotoxicity for the murine macrophaghes as the selectivity index (SI) fell into the safety range (SI ≥ 10). These nanomaterials exhibited good antileishmanial activity against the L. major stages that were comparable to that of Glucantime, the drug of choice. The IC₅₀ values of ZnS NPs and Glucantime against amastigotes were 11.59 ± 2.51 and 4.95 ± 2.51 μg/ml, respectively. The IC₅₀ values for ZnS NPs and Glucantime versus promastigote were 29.81 ± 3.15 and 14.75 ± 4.05 μg/ml, respectively. Further investigation is essential to explore the biological effects of ZnS NPs on animal and/or clinical models.Inspec keywords: nanoparticles, nanofabrication, microorganisms, antibacterial activity, ultraviolet spectra, visible spectra, nanobiotechnology, X‐ray diffraction, Fourier transform infrared spectra, zinc compoundsOther keywords: cytotoxicity, leishmanicidal activity, antioxidant activity, biosynthesised zinc sulphide nanoparticles, Phoenix dactylifera, green approach, UV–vis spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, Leishmania major promastigotes, Leishmania major amastigotes, MTT assay, macrophage model, oxidative metabolites, butylated hydroxyanisole, murine macrophaghes, selectivity index, glucantime, ZnS     

Green synthesis of silver nanoparticles using Mentha pulegium and investigation of their antibacterial,antifungal and anticancer activity

A simple and eco‐friendly method for efficient synthesis of stable colloidal silver nanoparticles (AgNPs) using Mentha pulegium extracts is described. A series of reactions was conducted using different types and concentrations of plant extract as well as metal ions to optimize the reaction conditions. AgNPs were characterized by using UV–vis spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering, zetasizer, energy‐dispersive X‐ray spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FTIR). At the optimized conditions, plate shaped AgNPs with zeta potential value of ‐15.7 and plasmon absorption maximum at 450 nm were obtained using high concentration of aqueous extract. Efficient adsorption of organic compounds on the nanoparticles was confirmed by FTIR and EDAX. The biogenic AgNPs displayed promising antibacterial activity on Escherichia coli, Staphylococcus aureus, and Streptococcus pyogenes. The highest antibacterial activity of 25 µg mL‐1 was obtained for all the strains using aqueous extract synthesized AgNPs. The aqueous extract synthesised AgNPs also showed considerable antifungal activity against fluconazole resistant Candida albicans. The cytotoxicity assay revealed considerable anticancer activity of AgNPs on HeLa and MCF‐7 cancer cells. Overall results indicated high potential of M. pulegium extract to synthesis high quality AgNPs for biomedical applications.Inspec keywords: silver, nanoparticles, nanofabrication, botany, antibacterial activity, biomedical materials, nanomedicine, ultraviolet spectra, visible spectra, transmission electron microscopy, atomic force microscopy, X‐ray chemical analysis, Fourier transform infrared spectra, electrokinetic effects, microorganisms, cellular biophysics, cancerOther keywords: antibacterial activity, antifungal activity, anticancer activity, stable colloidal silver nanoparticle, Mentha pulegium, plant extract, UV‐visible spectroscopy, transmission electron microscopy, atomic force microscopy, DLS, zetasizer, energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, methanolic extract, aqueous extract, plate‐shaped silver nanoparticle, zeta potential, plasmon absorption maximum, organic compounds adsorption, biogenic silver nanoparticle, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, fluconazole‐resistant Candida albicans, MTT assay, HeLa cancer cell, MCF‐7 cancer cell, Ag     

Biological synthesis and characterisation of silver nanoparticles using Pseudomonas geniculata H10 for pharmaceutical activity

In the present study, silver nanoparticles (SNPs) were synthesised for the first time using Pseudomonas geniculata H10 as reducing and stabilising agents. The synthesis of SNPs was the maximum when the culture supernatant was treated with 2.5 mM AgNO₃ at pH 7 and 40°C for 10 h. The SNPs were characterised by field emission scanning electron microscopy‐energy‐dispersive spectroscopy, transmission electron microscopy, dynamic light scattering, X‐ray diffraction and UV–vis spectroscopy. Fourier transform infrared spectroscopy indicated the presence of proteins, suggesting they may have been responsible for the reduction and acted as capping agents. The SNPs displayed 1,1‐diphenyl‐2‐picrylhydrazyl (IC₅₀  = 28.301 μg/ml) and 2,2′‐azinobis‐3‐ethylbenzothiazoline‐6‐sulphonate (IC₅₀  = 27.076 μg/ml) radical scavenging activities. The SNPs exhibited a broad antimicrobial spectrum against several human pathogenic Gram‐positive and Gram‐negative bacteria and Candida albicans. The antimicrobial action of SNPs was due to cell deformation resulting in cytoplasmic leakage and subsequent lysis. The authors’ results indicate P. geniculata H10 could be used to produce antimicrobial SNPs in a facile, non‐toxic, cost‐effective manner, and that these SNPs can be used as effective growth inhibitors in various microorganisms, making them applicable to various biomedical and environmental systems. As far as the authors are aware, this study is the first to describe the potential biomedical applications of SNPs synthesised using P. geniculata.Inspec keywords: X‐ray diffraction, proteins, scanning electron microscopy, enzymes, reduction (chemical), transmission electron microscopy, Fourier transform spectra, field emission electron microscopy, microorganisms, antibacterial activity, pharmaceutical technology, biotechnology, silver compoundsOther keywords: silver nanoparticles, Pseudomonas geniculata H10, field emission scanning electron microscopy‐energy‐dispersive spectroscopy, transmission electron microscopy, 1‐diphenyl‐2‐picrylhydrazyl, antimicrobial SNPs, Fourier transform infrared spectroscopy, Candida albicans, cytoplasmic leakage, microorganisms, biomedical applications, temperature 40.0 degC, time 10.0 hour, AgNO₃      

Study of bio‐fabrication of iron nanoparticles and their fungicidal property against phytopathogens of apple orchards

Current research trends on iron nanoparticles (FeNPs) are extensively focused because of their unique magnetic and electrical properties mostly applicable in essential medical devices. However, their fungicidal property against plant pathogens is very less known until date. Present study demonstrates a green technique for blending of FeNPs by utilising aqueous extract of neem leaf (Azadirachta indica A. Juss.) as reducing agent. Various characterisation techniques such as ultraviolet (UV)–visible spectroscopy, Fourier transform infrared spectroscopy transmission electron microscopy, scanning electron microscopy and X‐ray diffraction were performed for FeNPs. The authors’ results demonstrate the more cluster formation of FeNPs with size distribution of 20–80 nm. The bio‐fabricated FeNPs showed enhanced biocidal activity against economically important phytopathogens of apple such as Alternaria mali, Botryosphaeria dothidea and Diplodia seriata. From the obtained results, it can be suggested that further delve into green synthesis of FeNPs can address future biotechnology concerns to limit the synthesis of FeNPs by conventional methods. Furthermore, the field study on pathogenic fungi can be an effective step to verify their agricultural applications.Inspec keywords: biotechnology, iron, nanoparticles, microorganisms, electric properties, agrochemicals, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, spectrochemical analysis, nanofabricationOther keywords: biofabrication, iron nanoparticles, fungicidal property, apple orchard phytopathogens, magnetic properties, electrical properties, medical devices, plant pathogens, green technique, neem leaf, Azadirachta indica A Juss, ultraviolet‐visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, cluster formation, size distribution, biocidal activity, Alternaria mali, Botryosphaeria dothidea, Diplodia seriata, green synthesis, biotechnology, pathogenic fungi, size 20 nm to 80 nm     

Evaluation of antimicrobial activity of synthesised silver nanoparticles using Thymus kotschyanus aqueous extract

Development of a green chemistry process for the synthesis of silver nanoparticles (AgNPs) has become a focus of interest. Characteristics of AgNPs were determined using techniques, such as ultraviolet–visible spectroscopy (UV–vis), Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy and X‐ray diffraction (XRD). The synthesised AgNPs using Thymus kotschyanus had the most growth inhibition against gram‐positive bacteria such as Staphylococcus aureus and Bacillus subtilise, while the growth inhibition of AgNPs at 1000–500 µg/ml occurred against Klebsiella pneumonia and at 1000–250 µg/ml of AgNPs was observed against E. coli. The UV–vis absorption spectra confirmed the formation of the AgNPs with the characteristic peak at 415 nm and SEM micrograph acknowledged spherical particles in a nanosize range. FTIR measured the possible biomolecules that are responsible for stabilisation of AgNPs. XRD analysis exhibited the crystalline nature of AgNPs and showed face‐centred cubic structure. The synthesised AgNPs revealed significant antibacterial activity against gram‐positive bacteria.Inspec keywords: visible spectra, microorganisms, ultraviolet spectra, biomedical materials, nanofabrication, nanoparticles, X‐ray diffraction, scanning electron microscopy, molecular biophysics, X‐ray chemical analysis, nanomedicine, silver, antibacterial activity, Fourier transform infrared spectraOther keywords: green chemistry process, ultraviolet–visible spectroscopy, gram‐positive bacteria, silver nanoparticles, Thymus kotschyanus aqueous extract, UV–vis spectroscopy, Fourier transform infrared spectroscopy, FTIR analysis, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, SEM micrograph, X‐ray diffraction, XRD, Staphylococcus aureus, Bacillus subtilise, Klebsiella pneumonia, E. coli, UV–vis absorption spectra, face‐centred cubic structure, antibacterial activity, antimicrobial activity, wavelength 415.0 nm, Ag     

Antifungal and antiovarian cancer properties of α Fe2 O3 and α Fe2 O3 /ZnO nanostructures synthesised by Spirulina platensis

Candida albicans (C. albicans) infection shows a growing burden on human health, and it has become challenging to search for treatment. Therefore, this work focused on the antifungal activity, and cytotoxic effect of biosynthesised nanostructures on human ovarian tetracarcinoma cells PA1 and their corresponding mechanism of cell death. Herein, the authors fabricated advanced biosynthesis of uncoated α‐Fe₂ O₃ and coated α‐Fe₂ O₃ nanostructures by using the carbohydrate of Spirulina platensis. The physicochemical features of nanostructures were characterised by UV–visible, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction. The antifungal activity of these nanostructures against C. albicans was studied by the broth dilution method, and examined by 2′, 7′‐dichlorofluorescein diacetate staining. However, their cytotoxic effects against PA1 cell lines were evaluated by MTT and comet assays. Results indicated characteristic rod‐shaped nanostructures, and increasing the average size of α‐Fe₂ O₃ @ZnO nanocomposite (105.2 nm × 29.1 nm) to five times as compared to α‐Fe₂ O₃ nanoparticles (20.73nm × 5.25 nm). The surface coating of α‐Fe₂ O₃ by ZnO has increased its antifungal efficiency against C. albicans. Moreover, the MTT results revealed that α‐Fe₂ O₃ @ZnO nanocomposite reduces PA1 cell proliferation due to DNA fragmentation (IC₅₀ 18.5 μg/ml). Continual advances of green nanotechnology and promising findings of this study are in favour of using the construction of rod‐shaped nanostructures for therapeutic applications.Inspec keywords: nanocomposites, toxicology, nanofabrication, cellular biophysics, X‐ray diffraction, iron compounds, biochemistry, cancer, antibacterial activity, transmission electron microscopy, biomedical materials, wide band gap semiconductors, DNA, II‐VI semiconductors, visible spectra, molecular biophysics, ultraviolet spectra, nanomedicine, zinc compounds, nanoparticles, microorganisms, Fourier transform infrared spectraOther keywords: Spirulina platensis, antifungal activity, α‐Fe₂ O₃ nanoparticles, antiovarian cancer properties, Candida albicans infection, cytotoxic effect, biosynthesised nanostructures, human ovarian tetracarcinoma cell PA1, cell death, uncoated α‐Fe₂ O₃ , coated α‐Fe₂ O₃ nanostructures, α‐Fe₂ O₃ ‐ZnO nanocomposite, carbohydrate, physicochemical features, UV‐visible spectroscopy, high resolution transmission electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, broth dilution method, 2′, 7′‐dichlorofluorescein diacetate staining, PA1 cell lines, comet assays, MTT assays, rod‐shaped nanostructures, surface coating, PA1 cell proliferation, DNA fragmentation, green nanotechnology, Fe₂ O₃ ‐ZnO, Fe₂ O₃      

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     

Biogenic synthesis,characterisation and antifungal activity of gum kondagogu‐silver nano bio composite construct: assessment of its mode of action

The biogenic synthesis of silver nanoparticles was achieved by using gum kondagogu (Cochlospermum gossypium), a natural biopolymer (Gk‐AgNPs). Synthesised nanoparticles were characterised by using UV–visible spectroscopy, inductively coupled plasma‐atomic emission spectrometer, X‐ray diffraction, transmission electron microscope techniques. The silver nano particle size determined was found to be 3.6 ± 2.2 nm. The synthesised Gk‐AgNPs showed antifungal activity and exhibited minimum inhibitory concentration and minimal fungicidal concentration values ranging from 3.5 to 6.5 µg mL⁻¹ against Aspergillus parasiticus (NRRL‐2999) and Aspergillus flavus (NRRL‐6513). Scanning electron microscopy–energy dispersive spectroscopy analysis revealed morphological changes including deformation, shrunken and ruptured mycelium of the fungi. At the biochemical level, the mode of action revealed that there was an elevated level of reactive oxygen species, lipid peroxidation, superoxide dismutase, and catalase enzyme activity. Increased oxidative stress led to increased outer membrane damage, which was confirmed by the entry of N ‐phenyl naphthylamine to the phospholipid layer of outer membrane and higher levels of K⁺ release from the fungi treated with Gk‐AgNPs. This study explores the possible application of biogenic silver nanoparticles produced from gum kondagogu as potent antifungal agents. The potent antifungal activity of Gk‐AgNPs gives scope for its relevance in biomedical application and as a seed dressing material.Inspec keywords: antibacterial activity, nanocomposites, silver, nanofabrication, nanoparticles, biomedical materials, polymers, visible spectra, ultraviolet spectra, atomic emission spectroscopy, X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, microorganisms, X‐ray chemical analysis, enzymes, lipid bilayers, biomembranes, biomechanics, nanomedicineOther keywords: antifungal activity, gum kondagogu‐silver nanobiocomposite, Cochlospermum gossypium, natural biopolymer, UV‐visible spectroscopy, inductively coupled plasma‐atomic emission spectrometer, X‐ray diffraction, transmission electron microscope, fungicidal concentration, Aspergillus parasiticus, Aspergillus flavus, scanning electron microscopy, SEM‐energy dispersive spectroscopy, fungi deformation, ruptured mycelium, reactive oxygen species, lipid peroxidation, superoxide dismutase, catalase enzyme activity, oxidative stress, membrane damage, N‐phenyl naphthylamine, phospholipid layer, potassium ion release, biogenic silver nanoparticle, antifungal agent, seed dressing material, Ag     

Comparative study of antifungal effect of green and chemically synthesised silver nanoparticles in combination with carbendazim,mancozeb, and thiram

This study reports synthesis and characterisation of silver nanoparticles and their effect on antifungal efficacy of common agricultural fungicides. Silver nanoparticles were synthesised using biological and chemical reduction methods employing Elettaria cardamomum leaf extract and sodium citrate, respectively. Nanoparticles were then characterised using UV–Visible spectroscopy, X‐ray diffraction (XRD), transmission electron microscopy, and dynamic light scattering (DLS). While XRD assigned particles size of 31.86 nm for green and 41.91 nm for chemical silver nanoparticles with the help of the Debye–Scherrer formula, DLS specified monodisperse nature of both suspensions. Nanoparticles were tested individually and in combination with fungicides (carbendazim, mancozeb, and thiram) against fungal phytopathogens. Silver nanoparticles exhibited good antifungal activity and minimum inhibitory concentration (MIC) was observed in the range of 8–64 µg/ml. Also, they positively influenced the efficacy of fungicides. The mean MIC value (mean ± SD) for combination of all three fungicides with green AgNPs was 1.37 ± 0.6 µg/ml and for chemical AgNPs was 1.73 ± 1.0 µg/ml. Hence, it could be concluded that green AgNPs performed better than chemical AgNPs. Synergy was observed between green AgNPs and fungicides against Fusarium oxysporum. In conclusion, this study reports synthesis of monodisperse silver nanoparticles which serve as efficient antifungal agents and also enhance the fungicidal action of reported agricultural fungicides in combination studies.Inspec keywords: X‐ray diffraction, reduction (chemical), visible spectra, ultraviolet spectra, microorganisms, particle size, nanomedicine, nanofabrication, nanoparticles, agrochemicals, antibacterial activity, transmission electron microscopy, silver, light scattering, scanning electron microscopyOther keywords: antifungal effect, green silver nanoparticles, chemically synthesised silver nanoparticles, carbendazim, mancozeb, thiram, antifungal efficacy, common agricultural fungicides, biological reduction methods, chemical reduction methods, transmission electron microscopy, XRD assigned particles size, chemical silver nanoparticles, green AgNPs, chemical AgNPs, monodisperse silver nanoparticles, antifungal activity, agricultural fungicides, Elettaria cardamomum leaf extract, sodium citrate, UV‐visible spectroscopy, X‐ray diffraction, dynamic light scattering, size 31.86 nm, size 41.91 nm     

Synthesis,characterisation and anti‐tumour activity of biopolymer based platinum nanoparticles and 5‐fluorouracil loaded platinum nanoparticles

A facile and green synthesis of platinum nanoparticles [gum kondagogu platinum nanoparticles (GKPtNP)] using biopolymer‐ gum kondagogu was developed. The formation of GKPtNP was confirmed by ultraviolet (UV)–visible spectroscopy, scanning electron microscopy–energy dispersive X‐ray spectroscopy, transmission electron microscopy, X‐ray diffraction, Zeta potential, Fourier transform infrared, inductively coupled plasma mass spectroscopy. The formed GKPtNP are well dispersed, homogeneous with a size of 2–4 ± 0.50 nm, having a negative zeta potential (−46.1 mV) indicating good stability. 5‐Fluorouracil (5FU) was loaded onto the synthesised GKPtNP, which leads to the development of a new combination of nanomedicine (5FU–GKPtNP). The in vitro drug release studies of 5FU–GKPtNP in pH 7.4 showed a sustained release profile over a period of 120 min. Agrobacterium tumefaciens induced in vitro potato tumour bioassay was employed for screening the anti‐tumour potentials of GKPtNP, 5FU, and 5FU–GKPtNP. The experimental results suggested a complete tumour inhibition by 5FU–GKPtNP at a lower concentration than the GKPtNP and 5FU. Furthermore, the mechanism of anti‐tumour activity was assessed by their interactions with DNA using agarose gel electrophoresis and UV‐spectroscopic analysis. The electrophoresis results revealed that the 5FU–GKPtNP totally diminishes DNA and the UV‐spectroscopic analysis showed a hyperchromic effect with red shift indicating intercalation type of binding with DNA. Over all, the present study revealed that the combined exposure of the nanoformulation resulted in the enhanced anti‐tumour effect. Inspec keywords: nanoparticles, transmission electron microscopy, biomedical materials, tumours, ultraviolet spectra, DNA, drugs, electrophoresis, polymers, platinum, pH, drug delivery systems, biochemistry, X‐ray chemical analysis, microorganisms, molecular biophysics, electrokinetic effects, X‐ray diffraction, scanning electron microscopy, cancer, nanofabrication, visible spectra, nanomedicine, Fourier transform infrared spectra, materials preparationOther keywords: 5FU–GKPtNP, 5‐fluorouracil loaded platinum nanoparticles, gum kondagogu platinum nanoparticles, antitumour activity, scanning electron microscopy‐energy dispersive X‐ray spectroscopy, biopolymer‐based platinum nanoparticles, biopolymer‐based platinum nanoparticles, ultraviolet‐visible spectroscopy, UV‐visible spectroscopy, transmission electron microscopy, X‐ray diffraction, zeta potential, Fourier transform infrared spectroscopy, inductively coupled plasma mass spectroscopy, nanomedicine, in vitro drug release studies, sustained release profile, Agrobacterium tumefaciens, in vitro potato tumour bioassay, tumour inhibition, tumour activity, agarose gel electrophoresis, UV‐spectroscopic analysis, DNA, time 120.0 min, Pt     

Antibacterial and anticancer activity of biosynthesised CuO nanoparticles

The present investigation aims for the synthesis of copper oxide nanoparticles (CuO NPs) using Nilgirianthus ciliatus plant extract. The obtained CuO NPs were characterised by X‐ray diffraction, Fourier transform infrared spectrum, ultraviolet–visible spectroscopy, photoluminescence, scanning electron microscopy and transmission electron microscopy analysis. Significant bacterial activity was manifested by CuO nanoparticles against both Gram‐positive (Staphylococcus aureus and Staphylococcus mutans) and Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. The synthesised CuO NPs have good cytotoxicity against both human breast cancer cell line (MCF‐7) and lung cancer cell line (A549) with minimum cytotoxic effect on normal L929 (fibroblast) cell lines.Inspec keywords: microorganisms, ultraviolet spectra, nanomedicine, transmission electron microscopy, visible spectra, cellular biophysics, antibacterial activity, nanoparticles, X‐ray diffraction, lung, copper compounds, cancer, toxicology, biomedical materials, scanning electron microscopy, photoluminescence, Fourier transform infrared spectraOther keywords: antibacterial activity, anticancer activity, biosynthesised CuO nanoparticles, copper oxide nanoparticles, Nilgirianthus ciliatus plant, X‐ray diffraction, infrared spectrum, ultraviolet–visible spectroscopy, transmission electron microscopy analysis, bacterial activity, Gram‐negative bacteria, synthesised CuO NPs, human breast cancer cell line, Staphylococcus aureus, Staphylococcus mutans, CuO     

Plant‐mediated green synthesis of silver nanoparticles using Trifolium resupinatum seed exudate and their antifungal efficacy on Neofusicoccum parvum and Rhizoctonia solani

In recent years, biosynthesis and the utilisation of silver nanoparticles (AgNPs) has become an interesting subject. In this study, the authors investigated the biosynthesis of AgNPs using Trifolium resupinatum (Persian clover) seed exudates. The characterisation of AgNPs were analysed using ultraviolet–visible spectroscopy, X‐ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infra‐red spectroscopy. Also, antifungal efficacy of biogenic AgNPs against two important plant‐pathogenic fungi (Rhizoctonia solani and Neofusicoccum Parvum) in vitro condition was evaluated. The XRD analysis showed that the AgNPs are crystalline in nature and have face‐centred cubic geometry. TEM images revealed the spherical shape of the AgNPs with an average size of 17 nm. The synthesised AgNPs were formed at room temperature and kept stable for 4 months. The maximum distributions of the synthesised AgNPs were seen to range in size from 5 to 10 nm. The highest inhibition effect was observed against R. solani at 40 ppm concentration of AgNPs (94.1%) followed by N. parvum (84%). The results showed that the antifungal activity of AgNPs was dependent on the amounts of AgNPs. In conclusion, the AgNPs obtained from T. resupinatum seed exudate exhibit good antifungal activity against the pathogenic fungi R. solani and N. Parvum.Inspec keywords: silver, nanoparticles, botany, ultraviolet spectra, visible spectra, X‐ray diffraction, transmission electron microscopy, Fourier transform infrared spectra, nanobiotechnology, biological techniquesOther keywords: plant‐mediated green synthesis, silver nanoparticles, Trifolium resupinatum seed exudate, antifungal efficacy, Neofusicoccum parvum, Rhizoctonia solani, biosynthesis, ultraviolet–visible spectroscopy, X‐ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, plant‐pathogenic fungi, XRD analysis, TEM images, antifungal activity, temperature 293 K to 298 K, Ag     

Antineoplastic and antioxidant potential of phycofabricated silver nanoparticles using microalgae Chlorella minutissima

This study for the first time reports on fresh water microalgae Chlorella minutissima aqueous extract (CmAe) which was utilized for the biogenic synthesis of silver nanoparticles and tested their antineoplastic potential against Liver Hepatocellular Carcinoma (HepG2) cell line. The characteristic colour change of the reaction mixture from greenish yellow to yellowish brown confirmed the synthesis of Chlorella minutissima silver nanoparticles (CmAgNPs). Microscopic analysis revealed CmAgNPs to be spherical‐shaped with particle size ranging from 10 to 30 nm. The carbohydrates and proteins distinctive peaks were observed in Fourier transform infrared spectroscopy (FTIR) spectra which suggested these biomolecules acted as reducing and capping agents. Further, the crystalline nature of CmAgNPs was confirmed by X‐ray diffraction (XRD) analysis. CmAgNPs showed maximum free radical scavenging proving it to be more potent antioxidant agent as compared to CmAe. The mortality rate of HepG2 cells treated with CmAgNPs was found to be 91.8 % at 120 μg/ml with IC₅₀ value 12.42 ± 1.096 μg/ml after 48 h whereas no effect was observed on normal Human Embryonic Kidney (HEK 293) cells. Fluorescent images of the treated HepG2 cells revealed the formation of apoptotic bodies, condensed nuclei and cell shrinkage indicating their effectiveness against the cancer cells.Inspec keywords: silver, nanoparticles, nanomedicine, microorganisms, cellular biophysics, nanofabrication, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, proteins, Fourier transform infrared spectra, molecular biophysics, X‐ray chemical analysis, X‐ray diffraction, kidney, cancer, biomedical materialsOther keywords: antineoplastic potential, antioxidant potential, phycofabricated silver nanoparticle, Chlorella minutissima, freshwater microalgae, aqueous extract, liver hepatocellular carcinoma cell line, CmAgNP synthesis, field emission scanning electron microscopy, high‐resolution transmission electron microscopy, atomic force microscopy, dynamic light scattering, carbohydrate, protein, Fourier transform infrared spectroscopy, biomolecule, energy‐dispersive X‐ray spectroscopy, elemental silver signal, CmAgNP crystalline, X‐ray diffraction analysis, antioxidant agent, HepG2 cell mortality rate, human embryonic kidney, HEK 293 cell, fluorescent image, apoptotic body formation, condensed nuclei, cell shrinkage, cancer cell, antineoplastic agent, Ag     

Green synthesis of gold nanoparticles using Citrus maxima peel extract and their catalytic/antibacterial activities

The peel of Citrus maxima (C. maxima) is the primary byproducts during the process of fruit or juice in food industries, and it was always considered as biomass waste for further treatments. In this study, the authors reported a simple and eco‐friendly method to synthesise gold nanoparticles (AuNPs) using C. maxima peel extract as reducing and capping agents. The synthesised AuNPs were characterised by UV–visible spectrum, X‐ray diffraction (XRD), transmission electron microscope (TEM) and Fourier‐transform infrared spectroscopy (FTIR). The UV–visible spectrum of the AuNPs colloid showed a characteristic peak at 540 nm. The peaks of XRD analysis at (2θ) 38.30°, 44.28°, 64.62°, 77.57° and 81.75° were assigned to (111), (200), (220), (311) and (222) planes of the face‐centered cubic (fcc) lattice of gold. The TEM images showed that AuNPs were nearly spherical in shape with the size of 8–25 nm. The FTIR spectrum revealed that some bioactive compounds capped the surface of synthesised AuNPs. The biosynthesised AuNPs performed strong catalytic activity in degradation of 4‐nitrophenol to 4‐aminophenol and good antibacterial activity against both gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacterium. The synthesis procedure was proved simple, cost effective and environment friendly.Inspec keywords: gold, nanoparticles, nanofabrication, X‐ray diffraction, ultraviolet spectra, visible spectra, transmission electron microscopy, Fourier transform infrared spectra, crystal structure, catalysis, antibacterial activity, nanobiotechnologyOther keywords: gold nanoparticles, Citrus maxima peel extract, UV–visible spectrum, X‐ray diffraction, transmission electron microscope, Fourier‐transform infrared spectroscopy, XRD analysis, faced centre cubic lattice, TEM images, catalytic activity, 4‐nitrophenol, 4‐aminophenol, antibacterial activity, gram negative bacterium, gram positive bacterium, Au     

Comparative antileishmanial efficacy of the biosynthesised ZnO NPs from genus Verbena

This study describes ZnO NPs biosynthesis using leaf extracts of Verbena officinalis and Verbena tenuisecta. The extracts serve as natural reducing, capping and stabilization facilitators. Plant extracts phytochemical analysis, revealed that V. officinalis showed higher total phenolic and flavonoid content (22.12 and 6.38 mg g ⁻¹ DW) as compared to V. tennuisecta (12.18 and 2.7 mg g ⁻¹ DW). ZnO NPs were characterised by ultraviolet–visible spectroscopy, Fourier transform infrared, X‐ray diffraction, scanning electron microscope, transmission electron microscopy (TEM) and energy dispersive X‐ray. TEM analysis of ZnO NPs reveals rod and flower shapes and were in the range of 65–75 and 14–31 nm, for V. tenuisecta and V. officinalis, respectively. Bio‐potential of ZnO NPs was examined through their leishmanicidal potential against Leishmania tropica. ZnO NPs showed potent leishmanicidal activity with 250 µg ml⁻¹ being the most potent concentration. V. officinalis mediated ZnO NPs showed more potent leishmanicidal activity compared to V. tenuisecta mediated ZnO NPs due to their smaller size and increased phenolics doped onto its surface. These results can be a step forward towards the development of novel compounds that can efficiently replace the current medication schemes for leishmaniasis treatment.Inspec keywords: ultraviolet spectra, nanomedicine, nanostructured materials, visible spectra, X‐ray diffraction, antibacterial activity, nanoparticles, zinc compounds, scanning electron microscopy, microorganisms, nanofabrication, drugs, transmission electron microscopy, X‐ray chemical analysis, health and safety, particle size, renewable materials, diseases, Fourier transform infrared spectraOther keywords: flavonoid content, natural reducing stabilisation facilitators, ZnO nanoparticles synthesis, antileishmanial efficacy, Verbena tennuisecta, Verbena officinales, phytochemical analysis, phenolic content, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, energy dispersive X‐ray analysis, particle size, leishmaniasis treatment, leaf extracts, medication scheme, stabilisation facilitator, capping facilitator, size 14.0 nm to 31.0 nm, size 65.0 nm to 75.0 nm, ZnO     

Fabrication of cellulose nanoparticles through electrospraying

This study reports the fabrication of cellulose nanoparticles through electrospraying the solution of cellulose in N,N ‐dimethylacetamide/lithium chloride solvent as well as investigating the effect of electrospraying conditions and molecular weight on the average size of electrosprayed nanoparticles. Electrospraying of cellulose was carried out with the following range for each factor, namely concentration = 1–3 wt%, voltage = 15–23 kV, nozzle–collector distance = 10–25 cm, and feed rate = 0.03–0.0875 ml/h. The smallest nanoparticles had an average size of around 40 nm. Results showed that lowering the solution concentration and feed rate, as well as increasing the nozzle–collector distance and applied voltage led to a decrease in the average size of the electrosprayed cellulose nanoparticles. Fourier transform infrared analysis proved that no chemical change had occurred in the cellulose structure after the electrospraying process. According to X‐ray diffraction (XRD) results, cellulose nanoparticles showed a lower degree of crystallinity in comparison with the raw cellulose powder. XRD results also proved the absence of LiCl salt in the electrosprayed nanoparticles.Inspec keywords: polymers, nanoparticles, nanofabrication, spraying, molecular weight, particle size, Fourier transform infrared spectra, X‐ray diffraction, polymer structureOther keywords: cellulose nanoparticles, electrospraying, N,N‐dimethylacetamide‐lithium chloride solvent, molecular weight, solution concentration, feed rate, nozzle‐collector distance, Fourier transform infrared analysis, X‐ray diffraction, XRD, crystallinity, cellulose powder, voltage 15 kV to 23 kV