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In this research, the preparation of licorice extract and the biosynthesis of manganese oxide in the treatment of stomach cancer were investigated by examining the cytotoxicity of the stomach cancer line. The structural properties of manganese oxide were also studied through X-ray examination, scanning electron microscope (SEM), and infrared spectroscopy, where it was found that manganese oxide is polycrystalline, and the average grain size is 62.571 nm, but by SEM, the grain size is 93.49-47.74 nm. [ABSTRACT FROM AUTHOR]

A series of new 2-amino-7-hydroxy-8-methyl-4-aryl-4H-chromene-3-carbonitrile derivatives (4a-4g) have been synthesized by a one-pot multicomponent reaction of 2-methylresorcinol (1) and malononitrile (2) with various aldehydes (3). All the synthesised compounds (4a-4g) have been characterised using FT-IR, 1H NMR, 13C NMR, HR-MS and evaluated for swarming behaviour, biofilm formation, biofilm disruption and urease activity against P. mirabilis (MTCC-425). Among all the synthesized compounds, compounds 4a, 4b and 4g showed slightly inhibited swarming behaviour and compounds 4f and 4g inhibited biofilm formation with increasing concentration. SEM (Scanning Electron Microscope) imaging shows that compound 4e effectively disrupts the preformed biofilm. Also, compounds 4d and 4e showed 40% reduction in urease activity. The SAR studies of synthesized compounds are elaborated in detail to provide key structural features. Furthermore, molecular docking studies against urease could provide a mechanistic basis for the inhibition. The per-residue interaction analysis suggested the involvement of non-bonded and bonded interactions with the active site of urease. Hence, the aim of the below study was to synthesize new chromene derivatives and study their biological activities. [ABSTRACT FROM AUTHOR]

Introduction: Folate supplementation is crucial for the human body, and the chemically synthesized folic acid might have undesirable side effects. The use of molecular breeding methods to modify the genes related to the biosynthesis of folate by probiotics to increase folate production is currently a focus of research. Methods: In this study, the folate-producing strain of Limosilactobacillus reuteri B1-28 was isolated from human breast milk, and the difference between B1-28 and folA gene deletion strain AFolA was investigated by phenotyping, in vitro probiotic evaluation, metabolism and transcriptome analysis. Results: The results showed that the folate producted by the AFolA was 2-3 folds that of the B1-28. Scanning electron microscope showed that AFolA had rougher surface, and the acid-producing capacity (p = 0.0008) and adhesion properties (p = 0.0096) were significantly enhanced than B1-28. Transcriptomic analysis revealed that differentially expressed genes were mainly involved in three pathways, among which the biosynthesis of ribosome and aminoacyl-tRNA occurred in the key metabolic pathways. Metabolomics analysis showed that folA affected 5 metabolic pathways, involving 89 different metabolites. Discussion: In conclusion, the editing of a key gene of folA in folate biosynthesis pathway provides a feasible pathway to improve folate biosynthesis in breast milk-derived probiotics. [ABSTRACT FROM AUTHOR]

In this study, Chrysothemis pulchella leaf extracts were used to prepare gold nanoparticles (AuNPs) for anticancer and antimicrobial applications. The nanoparticles were characterized using UV-Visible spectroscopy, powder X-ray diffraction method, Scanning and transmission electron microscopic (SEM/TEM) techniques. The UV–vis spectroscopy revealed characteristic absorption band at 527 nm whereas X-ray diffraction analysis showed characteristic crystalline peaks typical of AuNPs and carbon peaks emanating from the plant extract. The energy dispersive X-ray spectroscopic (EDXS) studies showed the following elements: C, O, Na, Mg, Cl, K, Ca and Au. The microscopic analysis using Scanning and Transmission Electron Microscopes showed spherical nanoparticles with average size of 14.7 nm. Cytotoxic tests showed that the AuNPs were toxic to human embryonic kidney (HEK-293) and HELA cells at IC50 dosage of 34.5 and 54.05 µg respectively. The nanoparticles also proved to have broad spectrum antimicrobial properties as they inhibited the growth of some pathogenic micro-organisms. [ABSTRACT FROM AUTHOR]

In this study, aqueous Cystoseira crinite extract was used to successfully biosynthesize ZnO and C-doped ZnO samples. X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX), FTIR, and UV–vis techniques were used to characterize the biosynthesized samples. XRD technique confirmed the crystalline structure of ZnO and C-doped ZnO. EDX confirmed the formation of C-doped ZnO. SEM analysis revealed the spherical shape of the samples with agglomeration. FTIR spectra showed that phenolic compounds and protein molecules are present in the Cystoseira crinite extract. The photocatalytic activity of the prepared photocatalysts was investigated using crystal violet (CV) as a model of the cationic dyes and methyl orange (MO) as a model of the anionic dyes. 5%C-doped ZnO calcined at 500 °C showed an optimum photocatalytic efficiency of 92.7% and 87.8% for CV and MO dyes, respectively. The improved photocatalytic activity could be attributed to the narrower optical band gap of C doped ZnO than pure ZnO. The photocatalytic activity of CV and MO dyes follows the first-order kinetics with high correlation coefficient values. [ABSTRACT FROM AUTHOR]

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Metal nanomaterials could be applied in various fields and could be synthesized via living organisms such as plants, bacteria and fungi. Here, the ability of Xylaria sp.5 to produce silver nanoparticles (AgNPs) and α-glucosidase inhibitory activities by the AgNPs produced by Xylaria sp.5 were investigated. The culture broth of Xylaria sp.5 was used to synthesize AgNPs by using 0.1 M of silver nitrate (AgNO3) solutions. The mycogenic crystals were investigated for the morphological characteristics and chemical composition by scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The results showed that AgNPs were successfully produced. Moreover, AgNPs were tested for α-glucosidase inhibitory activities. The crude enzyme derived from rat intestine consisted of maltase and sucrase. The percentage of inhibition at 50 mg/ml of maltase and sucrase was 63.21 ± 0.67 and 54.42 ± 0.11, respectively. This study demonstrated that the supernatant culture broth of Xylaria sp.5 can be used to synthesize AgNPs which possess α-glucosidase inhibitory activities. Collectively, this method could be a promising alternative for low cost and non-polluting production of AgNPs which could be potentially utilized for the treatment of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) occupy a major part in biomedicine due to their unique physicochemical and biological properties including anti-microbial and anti-cancer activity. Evolvulus alsinoides (EA), commonly known as "Dwarf morning glory", is a flowering plant with unique medicinal properties. This plant is reported for its therapeutic significance in chronic bronchitis, asthma and even possesses higher pharmacological properties. In this study, we have reported the synthesis and biological properties of quercetin functionalized biogenic silver nanoparticles (Qur-EA-AgNPs). AgNPs were synthesized using EA Leaf extract and functionalized with Quercetin. Qur-EA-AgNPs were characterized using various techniques and their biocompatibility was investigated. The UV-Visible spectrum of EA-AgNPs revealed a maximum absorbance at 428 nm and quercetin functionalization results in a shift towards 390 nm. The intense peak in the Fourier-transform infrared spectroscopy (FTIR) spectra revealed the quercetin functionalization on EA-AgNPs. Scanning electron microscope (SEM) results confirmed the spherical morphology of quercetin-functionalized AgNPs with a size range around 20 nm which was further confirmed by High resolution transmission electron microscope (HRTEM). Energy Dispersive X-ray (EDX) spectrum evidenced the presence of Ag, C and O. Hemocompatibility of Qur-EA-AgNPs was confirmed from hemolytic assay showing < 5% hemolysis. Moreover, Annexin V PI assay on Qur-EA-AgNPs treated peripheral blood mononuclear cells (PBMCs) showed 78.58 % viability significantly which is comparable with the control cells and its biocompatible nature was proved. In the current study, quercetin-functionalized biogenic silver nanoparticles using E. alsinoides leaf extract have been fabricated and characterized using various techniques. TEM micrograph of functionalized nanoparticles revealed spherical-shaped particles. EDX analysis showed a major elemental composition of silver, carbon and oxygen. The particles are biocompatible towards PBMCs and the erythrocytes. [ABSTRACT FROM AUTHOR]

Green nanotechnology has recently been recognized as a more proper and safer tool for medical applications thanks to its natural reductions with low toxicity and avoidance of injurious chemicals. The macroalgal biomass was used for nanocellulose biosynthesis. Algae are abundant in the environment and have a high content of cellulose. In our study, we extracted parent cellulose from Ulva lactuca where consecutive treatments extracted cellulose to obtain an insoluble fraction rich in cellulose. The extracted cellulose has the same results obtained by matching it with reference cellulose, especially the same Fourier transform infrared (FTIR) and X-Ray diffraction (XRD) analysis peaks. Nanocellulose was synthesized from extracted cellulose with hydrolysis by sulfuric acid. Nanocellulose was examined by Scanning electron microscope (SEM) shown by a slab-like region as Fig. 4a and Energy dispersive X-ray (EDX) to examine the chemical composition. The size of nanocellulose in the range of 50 nm is calculated by XRD analysis. Antibacterial examination of nanocellulose was tested against Gram+ bacteria like Staphylococcus aureus (ATCC6538), Klebsiella pneumonia (ST627), and Gram-negative bacteria such as Escherichia coli (ATCC25922), and coagulase-negative Staphylococci (CoNS) to give 4.06, 4.66, 4.93 and 4.43 cm as respectively. Comparing the antibacterial effect of nanocellulose with some antibiotics and estimating minimal Inhibitory Concentration (MIC) of nanocellulose. We tested the influence of cellulose and nanocellulose on some fungi such as Aspergillus flavus, Candida albicans, and Candida tropicalis. These results demonstrate that nanocellulose could be developed as an excellent solution to these challenges, making nanocellulose extracted from natural algae a very important medical material that is compatible with sustainable development. [ABSTRACT FROM AUTHOR]

The gold nanoparticles (Au NPs) are used for various medical applications including biosensors, bioassays, photo-thermal treatments, and targeted drug delivery. Au NPs are synthesized by various methods, most of them are expensive and environmentally hazardous. In this study, the biosynthesis of Au NPs was performed by Sansevieria extract. The synthesized nanoparticle was investigated by X-Ray Diffraction (XRD), field-emission scanning electron microscopes, Fourier transform infrared spectroscopy (FTIR), and the UV–visible spectroscopy. The results showed that Sansevieria extract could produce spherical Au NPs with a diameter of about 40-70 nm in an economical and environmentally friendly synthesis method. It was also indicated by the MTT assay that the Au-NPs had low cellular cytotoxicity and promoted the antiproliferation effect of Cisplatin on prostate cancer cells (LN Cap). [ABSTRACT FROM AUTHOR]

The current research work attempted to investigate the strontium oxide nanoparticles (SrONPs) synthesized from the Lantana camara leaf extract. The bio-synthesized strontium nanoparticles were characterized by a UV-Visible spectrometer, Fourier Transform Infra-Red spectra (FTIR), Scanning Electron Microscope, X-Ray diffraction, and Dynamic Light Scattering. The biomolecules in the extraction of plant leaves behaved as good reducing and capping agents. The XRD peaks are indexed to 13.020, 22.240, 25.940, 31.310, 34.000, and 40.910, and the corresponding planes are (101), (112), (202), (213), (310), and (312) representing cubic structure for SrNPs. The strontium nanoparticles are unevenly globular in shape, and chaos, and exhibited cluster and partially even surfaces shown from the Scanning Electron Microscope. The antibacterial assay of the synthesized Lantana camara strontium oxide nanoparticles was evaluated. The binding effect was more at higher concentrations (100 µl) than the control for the species E. coli (21 mm), and A. niger (20 mm). [ABSTRACT FROM AUTHOR]

Plant mediated synthesis of metallic nanomaterials has emerged as a non-toxic and economical approach to their applications in diverse fields especially in biomedical sciences. Herein, this study first time reporting the use of Bombax ceiba flower extract for synthesis of selenium nanoparticles (SeNPs). Initially, SeNPs were confirmed by turning the color of reaction mixtures from light yellow to brick-red. Scanning electron microscope (SEM) and Transmission electron microscopy (TEM) images showed spherical shaped nanoparticles with smooth surface, size ranges between 30 and 150 nm. Dynamic light scattering (DLS) showed 100–150 nm for the distribution of particle size. X-ray diffraction (XRD) analysis revealed SeNPs crystallinity and confirmed by matching with selenium JCPD card No. 06-362. Energy-dispersive X-ray (EDX) spectra showed presence of pure Se peaks that corroborate the conversion of selenium ions into its elemental form by bio-reduction. Fourier-transform infrared spectroscopy (FTIR) spectra demonstrated that involvement of –OH, C–H, C=C, and C=O functional groups for SeNPs formation. Raman Spectra peaks at 250 cm−1 represent asymmetric trigonal selenium (t-Se). Ultraviolet-visible spectrophotometer (UV-Vis) peaks at 296 and 306 nm which is an indication of surface plasmon resonance (SPR). Moreover, maximum antibacterial activity of SeNPs were observed against Staphylococcus aureus- a gram positive bacteria that possess zone of inhibition (ZOI) 20 mm and Klebsiella pneumonia and Pseudomonas aeruginosa-gram negative bacteria with ZOI 28 mm, respectively, at concentration 100 µg/ml. In addition, the surface functionalities induced through extract components adhere over Se binds with urea and give its detection up to 1mM in milk sample. Conclusively, synthesized SeNPs may function as a potential antibacterial pharmaceutical candidate. [ABSTRACT FROM AUTHOR]

For the first time in this study, the effect of nanoparticles (NP) sizes on the antimicrobial activity of Ag NPs of different sizes obtained by the reaction of Ramalina fraxinea(R. fraxinea) extract and silver nitrate (AgNO3) at different concentrations was evaluated. For this purpose, characteristic light absorption points, and charge of the surface were determined by ultraviolet-visible spectroscopy (UV-Vis), and zeta potential, hydrodynamic diameters by dynamic light scattering (DLS) analysis, morphology, and diameters of NPs were determined by scanning electron microscope (SEM) analysis. The crystal structures of Ag NPs were confirmed by the X-ray diffraction (XRD) analysis map. The functional groups of the R. fraxinea extract, which plays an active role in the synthesis of Ag NP, were revealed by the peaks obtained by Fourier transform infrared spectroscopy (FT-IR) analysis. As a result of the characterization tests, the average diameter of Ag NPs increased from 14 nm to 48 nm with the increase in Ag NO3 concentration used in the synthesis of Ag NP (from 10-3 M to 5*10-2 M). The antimicrobial activity of Ag NPs against Staphylococcus aureus, Escherichia coli, and Candida albicans strains was evaluated depending on the size of the NPs. The antimicrobial effect of small-sized Ag NPs against the studied strains was quite effective compared to large-sized Ag NPs. As a result, it is seen that Ag NPs synthesized by using R. fraxinea extract in different sizes with a biologically inexpensive and eco-friendly method exhibit antimicrobial activity depending on the size. It is thought that the study data will be a guide for nanotechnology and biomedical field studies. [ABSTRACT FROM AUTHOR]

Novel cubic microstructures for the purposes of plasmonic Ag-based NPs were made using biological wastes produced from a microbial culture of Bacillus cereus (B. cereus) employing a bottom-up approach for the biosynthesis of metal-based nanomaterials. The unique surface plasmon resonance (SPR) of the as-prepared Ag-based NPs was detected at 405 nm. The infra-red spectrum revealed that the used biological waste effectively stabilized our Ag-based NPs. Scanning and transmission electron microscopes were used in order to evaluate the sizes and shapes of the distinctive structures present in our samples. The Ag NPs had a face-centered cubic structure, with a size of 64.4 nm for the (200) nano-crystallites, according to the X-ray diffraction that was conducted. The zeta potential was found to be −19.5 mV and the dynamic light scattering (DLS) size was 238.8 nm. Methylene blue's (MB) reaction with NaBH4 was used in order to measure the catalytic activity of the generated Ag-based NPs over a period of 1 to 5 min. With an astonishing reaction rate of 0.2861 min−1, the MB elimination percentage reached 67% in just 5 min, displaying outstanding catalytic activity. This work can therefore encourage the use of this biowaste for the ecologically benign, cost-effective, and long-term synthesis of innovative Ag-based nanoparticles and nanostructures, as well as in their use as catalysts in the catalytic reduction in MB. [ABSTRACT FROM AUTHOR]

Silver nanoparticles was reflected a powerful antimicrobial agents newly exclusively after growing incidence of diseases related with biofilm and multi-drug resistant pathogens which essential required to find a different path to eliminate that's challenge. So the aim of present study was to synthesize silver nanoparticles through biological method using bacteria Eschriesca coli. Biological silver nanoparticles were described by several techniques. The UV-visible spectrophotometric indicated absorbance peak at 246 to 356 nm, Fourier Transformer Infrared analysis (FTIR) revealed that carboxylic groups and poly phenolic groups are enclosed on the surface of both silver nanoparticles creating stabilized nanoparticles, and by scanning electron microscope (SEM), which shown that the biosynthesized silver nanoparticles were spherical in size 26.22 to 31.44 nm. Optimization of silver nanoparticle biosynthesis by E. coli was performed for parameters (temperature and pH and concentration of silver nitrate solution) and the results discovered that temperature 60°C, pH 7 and 3 M silver nitrate concentration were the optimum conditions for silver Nano particles biosynthesis by E. coli isolated from clinical samples of Thi - Qar (Nassryah) city-south Iraq. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles (TiO2 NPs) were prepared by Caricaceae (Papaya) Shell extracts. The Nanoparticles were analyzed by UV–Vis spectrums, X-ray diffractions, and energy-dispersive X-rays spectroscopy analyses with a scanning electron microscope. An antifungal study was carried out for TiO2 NP in contradiction of S. sclerotiorums, R. necatrixs and Fusarium classes that verified a sophisticated inhibitions ratio for S. sclerotiorums (60.5%). Germs of pea were individually preserved with numerous concentrations of TiO2 NPs. An experience of TiO2 NPs (20%, 40%, 80% and 100%), as well as mechanisms that instigated momentous alterations in seed germinations, roots interval, shoot lengths, and antioxidant enzymes, were investigated. Associated with controls, the supreme seeds germinations, roots and plant growth were perceived with the treatments of TiO2 NPs. Super-oxide dis-mutase and catalase activities increased because of TiO2 NPs treatments. This advocates that TiO2 Nanoparticles may considerably change antioxidant metabolisms in seed germinations. [ABSTRACT FROM AUTHOR]

Biological approach synthesis and characterization of Iron Sulfide (FeS) thin films from banana peel extract for contamination remediation of environment studied. Iron chloride, Sodium thiosulfate and Ethylene-di-amine-tetra acetate (EDTA) were used as precursor solutions without further purification. The nanoparticle of banana peel was extracted and prepared with synthesized FeS thin films and analyzed by X ray-diffraction for structural examination, Scanning electron microscope (SEM) for surface morphological analysis, Ultra-violet-visible-spectrometer (UV–Vis) and photo-luminescence spectro-photo-meter (P-L) for optical characterizations. XRD peaks are shown with recognized to (110), (200), (310), and (301) crystalline planes. The occurrence of this deflection peak are recognised the FeS crystal segment of the tetragonal crystalline systems. SEM micrographs of the films prepared biological method show the distribution of grains, which cover the surface of the substrate completely and are uniform and films deposited purely have defects. The photo-luminescence, absorbance, and transmittance strength of banana peel extract FeS thin film is greater than pure FeS thin films in which wide-ranging and symmetries groups were perceived. In the present study, the comparison of pure FeS thin films and Nano synthesized banana peel extract with FeS thin films was studied. It is observed that Nano synthesized banana fibre absorbs higher than pure FeS thin films in solar cell application. Finally, green synthesis is an ecofriendly, easy and cheap promising method for the fabrication of thin films for solar cell applications. [ABSTRACT FROM AUTHOR]

The aim of this work is to develop a green route for platinum nanoparticles (PtNPs) biosynthesized using Cordyceps flower extract and to evaluate their antioxidant activity and antibacterial activity. Different characterization techniques were utilized to characterize the biosynthetic PtNPs. The results showed that PtNPs were spherical particles covered with Cordyceps flower extract. The average particle size of PtNPs in Dynamic Light Scattering was 84.67 ± 5.28 nm, while that of PtNPs in Transmission Electron Microscope was 13.34 ± 4.06 nm. Antioxidant activity of PtNPs was evaluated by DPPH free radical scavenging ability test. The results showed that the antioxidant activity was positively correlated with the concentration of PtNPs, the DPPH scavenging efficiency of PtNPs (0.50–125.00 μg/mL) was 27.77–44.00%. In addition, the morphological changes of four kinds of bacteria (Escherichia coli, Salmonella typhimurium, Bacillus subtilis, Staphylococcus aureus) exposed to PtNPs were observed by scanning electron microscope. The results showed that the antibacterial activity of PtNPs against Gram-negative bacteria was stronger than that of Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is an ecofriendly biopolymer with diverse commercial applications. Its use is limited by the capacity of bacterial production strains and cost of the medium. Mining for novel organisms with well-optimized growth conditions will be important for the adoption of BC. In this study, a novel BC-producing strain was isolated from rotten fruit samples and identified as Lactiplantibacillus plantarum from 16S rRNA sequencing. Culture conditions were optimized for supporting maximal BC production using one variable at a time, Plackett–Burman design, and Box Behnken design approaches. Results indicated that a modified Yamanaka medium supported the highest BC yield (2.7 g/l), and that yeast extract, MgSO4, and pH were the most significant variables influencing BC production. After optimizing the levels of these variables through Box Behnken design, BC yield was increased to 4.51 g/l. The drug delivery capacity of the produced BC membrane was evaluated through fabrication with sodium alginate and gentamycin antibiotic at four different concentrations. All membranes (normal and fabricated) were characterized by scanning electron microscope, Fourier transform-infrared spectroscopy, X-ray diffraction, and mechanical properties. The antimicrobial activity of prepared composites was evaluated by using six human pathogens and revealed potent antibacterial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus mutans, with no detected activity against Pseudomonas aeruginosa and Candida albicans. [ABSTRACT FROM AUTHOR]

Introduction: Today, the biosynthesis of nanoparticles (NPs) assisted by microorganisms (particularly bacteria) received increasing attention. In this study, Bacillus subtilis strain SFTS, a bismuth-reducing bacterium, was isolated from the soil of a copper mine in the South of Iran and used for biosynthesis of bismuth NPs (Bi NPs). Materials and methods: Bacillus subtilis strain SFTS was identified by conventional identification tests and the 16S rDNA fragment amplification method. Characterizations of the bio-fabricated Bi NPs were examined using FTIR, EDS, XRD, TEM, and SEM analysis after purification of Bi NPs. In addition, the synergistic effect of biogenic Bi NPs in combination with different antibiotics was also investigated. Results: The attained results revealed that the biosynthesized Bi NPs average size was 22.36 nm and spherical in shape. The XRD pattern showed that the biosynthesized nanoparticles consisted only of Bi4 and monoclinic crystals. Furthermore, the results of antibacterial effect of Bi NPs in combination with various antibiotics showed that the nanoparticles represented the highest synergistic effect together with imipenem and the lowest effect in combination with tetracycline against clinical strains of E. coli and K. pneumoniae. Significant difference between synergistic effect of Bi NPs with antibiotics compared to antibiotics disc alone against E. coli and K. pneumoniae strains was observed (P<0.001). Conclusion: This study showed that Bi NPs biologically synthesized by Bacillus subtilis strain SFTS had a small size and different structure. However, finding about their antibacterial effect and related mechanism merit further investigations. [ABSTRACT FROM AUTHOR]

Starch stain is a common stain on paper artifacts. This stain leads to deformation of the surface of the paper and promotes the growth of microbiological deterioration. This study aims to use nanoparticles with an α-amylase enzyme to improve its quality for removing this type of stain from the surface of paper artifacts. Accelerated heat aging was used on starch stain applied on the new paper samples. The α-amylase enzyme was prepared. Silver and gold nanoparticles were biosynthesized by local fungal isolation. The produced silver and gold nanoparticles were characterized by using different techniques of analysis (UV- Visible spectroscopy, Transmission Electron Microscope (TEM), and X-Ray diffraction (XRD) analysis). Different concentrations of Ag-NPs and Au-NPs were added to the α-amylase reaction mixture to enhance its activity for removing starch stains. Some analytical techniques were also used for the evaluation of the efficiency of α-amylase and nanoparticles for removing starch stains (Color measurement, Scanning Electron Microscope (SEM), and pH measurement). The results proved that Ag-NPs at 20 microliters increased the activity to about 160%, whereas Au-NPs enhanced the activity to about 140% at a concentration of 5μL. The results showed that α-amylase enzyme incorporated with Ag-NPs exhibited better results more than its use alone. The addition of Ag-NPs to α-amylase enzyme for the removal of starch stain reduced the total color differences, improved the surface morphology. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacillus sphaericus was used for the green reduction of GO. • Successful reduction of GO was confirmed by characterizations. • Specific O H, C O and C O C bonds were reduced. • Green reduction of GO had good capacitance and conductivity. While chemical methods are often used to convert graphene oxide (GO) to reduced graphene oxide (RGO), chemical reduction is often environmentally unfriendly due to the high toxicity of many chemical reducing agents. To address this limitation, Bacillus sphaericus was used here for the green reduction of GO to RGO. Successful reduction was confirmed by various advanced characterization techniques including Ultraviolet–Visible (UV–vis), X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscope and Energy Dispersive Spectrometer (SEM-EDS). With a new peak attributable to RGO at 261 nm appearing in UV–vis and XRD spectra of the reduced product also developed a new peak at 2θ = 24.6° characteristic of RGO. Successful reduction was also supported by Raman spectroscopy which showed that the ratio of the intensity band (D band: G band) increased from 0.99 to 1.17. FTIR and XPS both confirmed that specific O H (3399 cm−1), C O (1734 cm−1) and C O C (287 eV) bonds were reduced. Cyclic voltammograms (CVs) showed that the produced RGO exhibited good conductivity (changed from 0.8 to 1.1 mW·cm−2). This work developed a green and easy operated method of synthesizing RGO using microorganisms. [ABSTRACT FROM AUTHOR]

The utilization of microorganisms like bacteria in the biological synthesis of silver nanoparticles (AgNPs) has attracted widespread attention due to their ability to synthesize different shape sizes, states, and morphology nanoparticles. In the current study, the green synthesis of AgNPs by Nocardiopsis sp. 16S ribosomal RNA analysis was used to characterize the Nocardiopsis sp. The synthesized AgNPs were characterized through multi‐instrument platforms such as transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), UV–Vis spectroscopy, scanning electron microscope (SEM), and X‐ray diffraction analysis (XRD). The antimicrobial activity of the synthesized AgNPs was determined by the agar plate diffusion method. The UV‐Vis absorbance analysis of the synthesized AgNPs has a significant absorbance at 384 nm, confirming the AgNPs' surface plasmon resonance. The SEM and TEM characterizations indicate that the particle size ranges from 2 to 10 nm and is spherical. Additionally, the FTIR spectra revealed bands from 476 to 3819cm−1, respectively. The XRD planes study pronounced strong bands ranging are between 111 and 311 corresponding to cubic face‐center of the silver. Also, the antimicrobial activity of AgNPs indicated the biogenic AgNPs could control the growth of the clinical isolates. The AgNPs produced by Nocardiopsis sp. supernatant could be used in different nanomedicinal applications. [ABSTRACT FROM AUTHOR]

Silver (Ag) nanoparticles were successfully synthesized under ambient temperature employing Leucas Aspera (LA) leaves. The synthesis of silver nanoparticles at first confirmed by noting variations in the colour and subsequently morphological characteristics of prepared LA–Ag nanoparticles have been explored by using HR-TEM, and the particle size was found to be 3.67 nm which is in good agreement with XRD. SAED pattern represent the polycrystalline nature of Ag and crystallographic planes are close agreement with XRD. Implementing Diffraction Light Scattering (DLS) the average size is estimated to be 7 nm and the polydispersity index (PDI) was noticed to be 0.209 evince the uniform distribution. The same synthesised nanoparticles (NPs) were encapsulated further within a matrix of polyvinyl alcohol (PVA). Moreover, prepared nanocomposite films were characterised and correlated with both PVA-Ag matrix and pure PVA. To examine the optical characteristics of both LA–Ag-NPs and pristine PVA films were characterised via UV–Visible spectra. The influence of doping PVA with LA–Ag-NPs was being explored, i.e., structural, and morphological improvements including optical band gap, absorption coefficient, refractive index as well as optical conductivity. Besides, Fourier Infrared Spectroscopy benefitted to classify the alterations in the functional group. Scanning electron microscope visuals of synthesized nanoparticles reveal spherical shape in a polymer matrix, although the outcomes of energy dispersion findings support the appearance of silver. The structural parameters were determined by the use of X-ray diffraction studies, reflecting the d-spacing values and the crystalline nature with doping silver nanoparticle in PVA. This article addresses the research on structural and optical properties of LA–Ag–PVA nanocomposite films. [ABSTRACT FROM AUTHOR]

In the present investigation, iron nanoparticles were synthesized by using mushroom extract. The production of iron nanoparticles from P. florida was initially confirmed by color changes from brown to dark brown within 30 min at 60° and further characterized by Ultraviolet-Visible spectroscopy and scanning electron microscope with Edax. The biosynthesized iron nanoparticles were subjected to antimicrobial activities and showed higher zone of inhibition against Candida glabrata followed by Micrococcus mucilaginosus, Pseudomonas aeruginosa, Candida albicans, Klebsiella terrigena, K. pneumoniae, Escherichia coli, Candida sp., Bacillus cereus and Staphylococcus aureus. This extract was confirmed as effective against microorganisms which was well comparable with standard antibiotics. The present study has recommended that iron nanoparticles from mushrooms have great potential to act as safe alternative to antibiotics to fight the challenges of drug discovery. [ABSTRACT FROM AUTHOR]

This study describes the hydrothermal synthesis of cupric oxide nanoparticles (CuO NPs) using Mint extract agent. A mixture of 0.1 M copper nitrate and a mint extract was hydrothermally treated at a temperature of 180 °C for two hours. Meanwhile, the Mint leaf extract had reduced the copper ions of the nanoparticles after five minutes, resulting in dark-green precipitation. The structural and optical properties of the nanoparticles were studied using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and UV-Vis spectroscopy. The nanoparticles showed a simple cubic structure with a crystallite size range of 22 nm ‒ 25 nm. According to the UV-Vis spectrum, an absorption peak was observed at 346 nm. The antibacterial activity was checked against Escherichia coli (E-coli) and Bacillus subtilis (B-subtilis) cultures by which the inhibition zones were found to be 35 mm and 38 mm, respectively. It is concluded that the CuO NPs have a good ability to resist microbes. [ABSTRACT FROM AUTHOR]

Dillenia indica L. is a traditional medicinal plant well known for its ability to cure various human diseases. In the current study, silver nanoparticles have been synthesized by simple and eco‐friendly method using Dillenia indica extract. The green synthesized nanoparticles were characterized by Fourier transform infrared (FTIR), UV–visible spectroscopy, Atomic force microscopy (AFM), High‐resolution transmission electron microscopy (HR‐TEM), Zeta Potential and Size Distribution. UV–visible and FTIR spectra, AFM, HR‐TEM and Zeta Potential readings and size distribution conformed that the synthesized silver particles were in the size of nano. The green synthesized silver nanoparticles were subjected for antibacterial activity against Gram‐positive bacteria Enterococcus faecalis and Gram‐negative bacteria Escherichia coli by agar well diffusion method. The synthesized AgNPs exhibited significant inhibition of 27 and 16 mm against the test bacteria at 0.25 mg/ml. Further the antibacterial activity was confirmed by live and dead cell assay by fluorescence microscopy and morphological changes of bacteria were studied by Scanning electron microscope (SEM). The study recommends that the synthesized silver nanoparticles using Dillenia indica extract have potential application in inhibition of bacteria owing to their potent antibacterial activity. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) are successfully synthesized via a facile and eco-friendly biosynthesis approach. Ginkgo biloba (G. biloba) leaf is an extract used as bio-aqueous solution for the preparation of the AuNPs. Photo-chemically, the G. biloba leaf plays dual roles wherein it serves as reducing and stabilizing agent. Through this approach, the use of toxin-induced chemical is completely avoided making the approach a green chemistry. Several synthetic parameters such as reactant concentration, media pH, reaction time and temperature are optimized which in turn enables the formation of AuNPs with uniform size. Various analytical techniques including scanning electron microscope (SEM), high resolution-transmission electron microscopic (HRTEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy, fringe spacing and selected area diffraction (SEAD) pattern, and dynamic light scattering (DLS) are used for AuNPs characterization. The AuNPs exhibit cubic structure and spherical shape with average size of 18.95 ± 5.95 nm. The homemade AuNPs show promises in the catalytic decolorization of azo-dyes in the presence of sodium borohydride (NaBH4). In addition, the AuNPs show appreciable sensitivity for the detection of Cr(VI) with a detection limit found to be 0.1–0.8 μM. This study is expected to spur further works on the use of metal nanoparticle for environmental pollution remediation. [ABSTRACT FROM AUTHOR]

• Zirconium oxide nano-particles derived from novel Crescentia Cujete fruits through bio synthesis process. • The crystalline structure of the green synthesized ZrO 2 nano-composite was validated by scanning electron microscopy. • The UV–Visible spectrum analysis of the calabash fruit extract revealed a prominent maximum absorbance at 361nm. • Fourier transform infrared analysis identified the functional groups in calabash fruit extract. • Enhanced efficiency of diesel engine and lower exhaust emissions using zirconium oxide nano-particles. The current Study focuses on a biosynthesis of Zirconium Oxide nano-additives (ZrO 2) from the novel Crescentia Cujete fruits, which is simpler, non-hazardous, and ecologically friendly technique when compared to the complex chemical methods. The first phase discussed the characterization of Zirconium oxide nano-particles. Fourier Transform- Infra Red analysis revealed that phenolic compounds with O H stretching vibrations caused the compound's absorption peak at 3434 cm−1. Scanning Electron Microscope analysis revealed the existence of trigonal and spherical forms in the green ZrO 2 nanocomposite. The UV–Visible spectrum analysis of the Calabash fruit extract revealed a prominent maximum absorbance at 361nm. The second phase examined the effects of using biodiesel made from used engine oil along with a bio-synthesized nano-additives zirconium oxide on the efficiency and emission characteristics of a diesel engine. The experimental results revealed that Zirconium oxide nano-additives reduced brake specific fuel consumption (BSFC) in waste engine oil methyl ester (WEOME25) fuel blend. WEOME25 with ZrO 2 nano-particles increases BTE by 1.7% at 50ppm, 3.41% at 75ppm, and 3.91% at 100ppm. WEOME25+ZrO 2 at 50ppm, 75ppm, and 100ppm increased cylinder pressure by 1.38%, 2.21%, and 1.87%, respectively. Zirconia nano additions boost combustion and reduce HC, CO and Smoke emissions except NO x emission. [Display omitted] [ABSTRACT FROM AUTHOR]

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In the current scenario, biosynthesis has a major trend in the world due to its eco-friendly approach, effectiveness and low cost. In this experiment Aluminium Oxide nano powder was extracted from 'Muntingia Calabura' leaf with aluminium nitrate as precursor. An attempt has been made to develop the properties of sisal/coir, sisal/banana and banana/coir based hybrid composite with addition of aluminium oxide (Al2O3) nano powder. Compression moulding technique was adapted to fabricate the epoxy based natural fiber composites. Nano Al2O3 powder was added in 0, 1, 2 and 3 wt%. The results demonstrate that addition of nano powder up to 3 weight (wt) percentage improvise the tensile, flexural and impact properties for all incorporated hybrid fibers. Residual wt% for sisal/coir, sisal/banana and banana/coir hybrid composites enhanced from 27.15 to 29.14, 26.07 to 31.33% and 23.76 to 27.50% by 3% nano substitution. Degradation temperature improved in different stages of hybrid combinations. Scanning electron microscope (SEM) images clearly showed the reduction of fiber breakage, matrix breakage and void gaps due to alumina nano powder addition. [ABSTRACT FROM AUTHOR]

Nanoparticle synthesis using plants is an alternative to conventional physical and chemical methods. In this article, we demonstrate the synthesis of ZnO nanoparticles (NPs) using leaf extract of Plectranthus amboinicus. The prepared ZnO NPs have been characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and Fourier Transform infrared spectroscopy (FTIR). The biosynthesized ZnO NPs then applied for electrode surface modification. The modified electrode was successfully used for electrochemical determination norfloxacin. The comparison results show that the biosynthesized ZnO NPs had a superior electrochemical performance towards norfloxacin detection compared with that of bare electrode and chemically synthesized ZnO NPs. [ABSTRACT FROM AUTHOR]

This study focuses on time-dependent microwave-assisted biosynthesis of silver nanoparticles using aqueous peel extracts of Citrus paradisi as a reducing, stabilizing and capping agent with emphasis on its antibacterial property. Optical, structural and morphological properties of the synthesized Citrus paradisi peel extract silver nanoparticle (CPAgNp) were characterized using UV-visible spectrophotometer, transmission electron microscope (TEM), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), Brunauer–Emmett–Teller (BET) and X-ray diffractometer (XRD). The antimicrobial activity was evaluated using the well- and disc-diffusion methods. Characteristic surface plasmon resonance (SPR) wavelength in the range of 420–440 nm at an optimized intensity growth rate typical of silver nanoparticles was obtained. The synthesized CPAgNp are spherical in shape having the size range of 14.84 ± 5 nm and possessing fcc unit phase structure. The Citrus paradisi peel extract mediated AgNp were found to possess a broad-spectrum antimicrobial activity against water-borne pathogenic microbes. [ABSTRACT FROM AUTHOR]

This study reports biosynthesis of gold-nanoparticles (AuNPs) by using β- d -glucans isolated from the yeast Yarrowia lypolitica D1. β- d -glucans serve as reducing and stabilizing mediators that induce the formation of AuNPs on the outer surface of the own β- d -glucan. The systems were physicochemically characterized by ultraviolet visible (UV–Vis) spectroscopy, high-resolution transmission electron microscopy (HR-TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and dynamic light scattering (DLS) analyses. The results revealed the generation of AuNPs with quasi-spherical shape or large one dimension (1D) gold-nanostructures (AuNSs) depending on the HAuCl 4 concentration. A cytotoxic study was assessed in mouse splenocytes. Contrary to that expected, important cytotoxicity was found in all β- d -gluc+AuNPs systems by an oxidative stress increase. This study discusses the cytotoxic mechanism, suggesting that the resulting β- d -gluc+AuNPs systems may not be candidates for the formulation of immunostimulants or nanocarriers for biomedical applications. • This work reports a novel methodology to produce metallic nanoparticles or 1D nanostructures using yeast β-D-glucans. • Bare β-D-glucan or AuNPs alone are not cytotoxic for mice splenocytes. • β-D-gluc+AuNP10 and β-D-gluc+AuNP50 caused cytotoxicity inmice spleen leukocytes. • The β-D-gluc+AuNPs systems may not be suitable candidates as immunostimulants or nanocarriers for biomedical applications. [ABSTRACT FROM AUTHOR]

The study compared the antibacterial activity of synthesized ZnO nanoparticles (NPs) from fresh leaf and fresh stem bark aqueous extracts of Carica papaya against five selected microbes: Staphylococcus aureus, (Gram positive (+ve)), Escherichia coli (Gram negative (-ve)), Acinetobacter baumanni (Gram-ve), Exiguobacterium aquaticum (Gram+ve), and Klebsielia pneumonia (Gram +ve). The morphological features of the biosynthesized ZnO NPs were analyzed using transmission electron microscope (TEM) and scanning electron microscope (SEM); the Fourier-transform infrared spectrometer (FTIR) technique was used to observe the surface functional groups. The experimental results indicated that ZnO NPs were successfully synthesized using modified hydrothermal technique, which showed agglomerated flake-like or petal-like shapes with the organic extract surrounding the formed particles. The average particle size of the synthesized ZnO nanoparticles determined by SEM ranged between 54-97 nm with the width and length of the petal-like structures been 30 nm and 62 nm respectively. The average ZnO NPs from fresh stem bark extract of Carica papaya with higher concentrations (100-1000 ppm) demonstrated a higher antibacterial activity than the fresh leaf extracts. On the other hand, ZnO NPs from fresh leaf extracts of lower concentrations (25-50 ppm) rather showed a suitable result than the fresh stem bark. In general, ZnO NPs showed a positive antibacterial result towards the selected microbes. This shows that, the synthesized ZnO NP can be a substitute to chemical methods. [ABSTRACT FROM AUTHOR]

Biofabrication of nanoparticles using plant sources is considered the most vital method for nanoparticle syntheses, as the use of plant materials not only makes the process eco-friendly but also its abundance makes it less expensive. In this study, we aimed to develop a rapid and simple procedure for the synthesis of gold nanoparticles using aqueous Cressa cretica leaf extract as a reducing agent as well as a capping agent. The characteristics of biofabricated gold nanoparticles were examined using ultraviolet-visible absorption spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray powder diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). As the results, the biofabricated gold nanoparticles were of hexagonal, pentagonal, spherical and rod shapes with 15-22 nm in size. FTIR studies disclosed that hydroxyl, amide and amine groups of Cressa cretica leaf broth were liable for the formation and stabilization of the gold nanoparticles. The antibacterial activity of the gold nanoparticles against human pathogens showed significant zones of inhibition. It confirmed that the biofabricated gold nanoparticles have great promise as an antibacterial agent. The biofabricated gold nanoparticles were used as catalysts in the reduction of 4-nitrophenol using sodium borohydride. The catalytic activity studies exhibited that the biofabricated gold nanoparticles had prominent catalytic activity. Furthermore, this green biofabric approach is a fast and easy alternative to chemical synthesis. [ABSTRACT FROM AUTHOR]

Background: Antibiotic resistance is a life threating problem and the need for an alternative is increasing worldwide. Objective of this study is: Detecting the combination effect of AuNps with Amoxicillin/clavulanate (AMC) antibiotic against antibiotic resistant clinical bacterial isolates. Materials and methods: Gold nanoparticles were biosynthesized using food origin Citrobacter freundii isolate (C2) which was isolated from chicken meat samples by pour plate method and identified using cultural characteristics, biochemical tests and the identification to the species level was completed by Vitek-2 system and this identification was confirmed by sequencing of the 16 s r RNA. The biosynthesis of gold nanoparticles was optimized in order to achieve the finest AuNps with a diameter range (30-60) nm. and the biosynthesized gold nanoparticles were characterized by visual observation and then characterized using various characterization techniques: Uv-vis spectroscopy, Fouriertransform infrared spectroscopy (FTIR) analysis, atomic force microscopy (AFM) analysis and scanning Electron Microscope (SEM). The combination effect of AuNps with AMC antibiotic was detected against clinical bacterial isolates. Results: The results revealed the biosynthesized AuNPs were roughly spherical and poly-dispersed, and they were highly effective with concentration (62.5 μg/ml) that inhibit the bacterial growth, MIC values of AMC antibiotic against clinical isolates were determined as 500 μg/ml, while the combination of gold nanoparticles and AMC had wide spectrum of antibacterial activity against different isolates of the bacteria that used in this study. Conclusion: There was a significant synergistic effect between the biosynthesized gold nanoparticles when used in combination with antibiotic where the minimum inhibitory concentrations of the combination (AuNps/AMC) were less than its concentration when each of them (AuNps) or (AMC) used separately. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel biosynthesis of MnO 2 from Ziziphus spina-Christi leaves. • Decoration the green MnO 2 by Zn NPs. • Characterization of the biosynthesis MnO 2 and Zn/Mn 2 O 4. • Photocatlysis of various organic dyes under sunlight irradiation. An aqueous leaf extract of Ziziphus spina-Christi is used to synthesize manganese oxide nanoparticles (MnO 2 NPs) and zinc-coated manganese oxide nanoparticles (Zn/Mn 2 O 4 NC). The study aims to investigate the photocatalytic degradation efficiency of MnO 2 NPs and Zn/Mn2O4 NC in relation to the azo dyes methylene blue (MB), m-Toluidine (mT), and P-Toluidine (pT). X-ray diffraction analysis (XRD) confirmed the crystalline nature of the biosynthesized MnO2 NPs and Zn/Mn 2 O 4 , revealing their respective crystallite sizes to be approximately 14.65 nm and 22.97 nm. The scanning electron microscope (SEM) images demonstrated that the MnO 2 NPs exhibit a tetragonal and spherical shape, while the Zn/Mn 2 O 4 particles possess a spherical shape. UV–vis spectroscopy measurements indicated that the MnO 2 NPs and Zn/Mn 2 O 4 exhibit indirect bandgaps with energy values of 1.46 eV and 1.14 eV, respectively. Fourier transform infrared (FTIR) analysis revealed the presence of organic compounds containing C O and OH groups, such as carbohydrates, phenolic acids, tannins, and flavonoids derived from Ziziphus spina-Christi , suggesting a high likelihood of stability for the biosynthetic MnO 2 and Zn/Mn 2 O 4 materials. Interestingly, the photocatalytic degradation of the biosynthetic MnO 2 and Zn/Mn 2 O 4 provided good efficacy against the Methylene Blue (MB), m-Toluidine (mT), and P-Toluidine (pT) where the Zn/Mn 2 O 4 exhibit an excellent degradation were 99.2, 99.8 and 98.4 % after 75 min. The biosynthetic MnO 2 NPs and Zn/Mn 2 O 4 NCs resulting from using aqueous ZSCLE were cost-effective and eco-friendly, and the decoration of MnO 2 NPs by Zn improved their effectiveness. [ABSTRACT FROM AUTHOR]

Recently, applying industrial bio-processing strategies are being a promised tool that used to produce large quantities of bioactive metabolites from different microbial cells. So in this study, the statistical experimental designs (Plackett-Burman and Box-Behnken) were used for optimization of local S. violaceoruber SYA3 biomass production (18g/l) and fabrication the highest nano-ZnO mass weight (15g/l). Since the nano-ZnO was fabricated by using the extracted periplasmic metabolites as a reducing agent and Zn(NO3)2.6 H2O as a precursor. The morphological properties and size of the nano-ZnO were evaluated using SEM and TEM analysis. Large-scale production was studied via batch fermentation mode using semi-industrial scale bioreactor (8.9L). The biomass production and the fabricated nano-ZnO was (22.8g/l) and (56.8g/l), respectively. Finally, this work reported developing a new cheap and eco-friendly nano-ZnO fabrication method and applying nano-ZnO as a strong anti-phytopathogens agent. [ABSTRACT FROM AUTHOR]

Owing to the numerous biological applications, cost effectiveness and low cytotoxicity of the biomimetic nanoparticles (NPs), the authors optimised the production of silver NPs (AgNPs) using aqueous extract of Teucrium stocksianum Boiss. The NPs were characterised by ultraviolet‐visible (UV‐vis) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS) and Fourier transform‐infrared spectroscopy (FTIR). The UV‐vis spectroscopy revealed a surface plasmon resonance (410‐440 nm) at an incubation temperature of 90°C when 1 mM Ag nitrate combined to 5 mg/ml extract concentration in the ratio of 1:10. DLS results show an average zeta size of ∼44.61 nm and zeta potential of −15.3 mV. SEM and XRD confirmed the high crystallinity and cubical symmetry with an average size below 100 nm. FTIR measurement shows the presence of various functional groups, responsible for the capping and reduction of Ag metal. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide cell viability assay shows that AgNPs are less cytotoxic to J774 and L929 cells as compared with enhanced anticancer activity with low IC50 concentrations (68.24 µg/ml) against Michigan Cancer Foundation‐7 (MCF‐7) cells. The ethidium bromide/acridine orange assay shows that the AgNPs kill the cell by apoptosis. Overall, the results show that AgNPs possesses potent anticancer activities. [ABSTRACT FROM AUTHOR]

Summary: In this work, silver nanoparticles (Ep-AgNPs) were synthesised using Echinacea pallida (Nutt.) Nutt. The dried leaves of E. pallida were collected and heated at 55 °C in deionized water, and filtered, and the leaf extract was treated with AgNO3 to produce the Ep-AgNPs. The Ep-AgNPs were analyzed by Ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM). The characteristic hydroxyl gave the peak at 3147 cm-1. In UV-Vis analysis, observation of absorption band at 468 nm proved the achievement of Ep-AgNPs synthesis. SEM analysis presented the spherical shape of nanostructures with an average size of 77.82 nm. The face-centered crystal structure of Ep-AgNPs was revealed by the XRD analysis. The 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH') scavenging, ferric reducing antioxidant power (FRAP), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS'~) assays were employed for antioxidant study in which Ep-AgNPs exhibited excellent antioxidant effect. Ep-AgNPs displayed outstanding DPPH' activity (6.34, IC50, µg/ml) compared to the standard BHT (10.78, IC50, µg/ml). The high activity was observed for ABTS'~ and reducing power assays as well. Hence, Ep-AgNPs could be a valuable material for the food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

CuO/Al 2 O 3 nanocomposites were successfully prepared via a thermal decomposition method using green tea extract as a precipitating agent. The biosynthesized CuO/Al 2 O 3 nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), fourier transform infrared spectroscopy (FT-IR), X-ray energy dispersive spectroscopy (EDS), N 2 adsorption (BET), ultraviolet–visible (UV–Vis) spectroscopy and transmission electron microscope (TEM). Also, the electrochemical hydrogen storage properties of porous CuO/Al 2 O 3 nanocomposites with various aspect ratio of Cu:Al were studied. The discharge capacity of CuO/Al 2 O 3 nanocomposites at the first cycle with 2:1 ratio of each compartments obtained at 330 mAh/g while enhanced to 6750 mAh/g after 14 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • SNPs were successfully synthesized utilizing pomelo peel extract as a reducing agent, • The ultrasound-assisted reduction was faster compared to room temperature reduction. • The crystallite size of SNPs was 35 to 40 nm in diameter. • Phenolic compounds were able to cap metal ions and reduce them. • The SNPs were effective as antibacterial agents against E. coli and B. cereus. Synthesis of silver nanoparticles by green route is an emerging technique drawing more attention recently because of several advantages over the conventional chemical ways. The overall objective of the research was focused on the green synthesis of silver nanoparticles using pomelo peel waste via a rapid and eco-friendly ultrasonic-assisted technique and their characterization. Different factors affecting the synthesis, like methodology for the preparation of extract and various treatment conditions for the synthesis, were also studied. The developed nanoparticles were characterized for their optical, molecular, microstructural, and physical properties by UV–visible spectroscopy, dynamic light scattering (DLS), zeta-potential measurements, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). The green synthesized nanoparticles were found almost spherical when treated at room and high temperatures and cubical when treated with ultrasonication. As obtained from the XRD studies, the size of crystallite nanoparticles was 35 to 40 nm in diameter. The EDX, FT-IR, and zeta potential analysis corroborated the role of phenolic compounds in capping and reduction of the metal ion. The capping ability of the polyphenolic component in the extract was used to achieve size stability. The nanoparticles also showed antibacterial activity against gram-negative and gram-positive bacteria, owing to the inherent antibacterial capability of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Improvement of reliable and eco-friendly process for synthesis of metallic nanoparticles is a significant step in the field of application nanotechnology. One approach that shows vast potential is based on the biosynthesis of nanoparticles using micro-organisms. In this study, biosynthesis of silver nanoparticles (AgNP) using 30 cyanobacteria were investigated. Cyanobacterial aqueous extracts were subjected to AgNP synthesis at 30 °C. Scanning of these aqueous extracts containing AgNP in UV-Visible range showed single peak. The λ max for different extracts varied and ranged between 440 and 490 nm that correspond to the 'plasmon absorbance' of AgNP. Micrographs from scanning electron microscope of AgNP from cyanobacterial extracts showed that though synthesis of nanoparticles occurred in all strains but their reaction time, shape and size varied. Majority of the nanoparticles were spherical. Time taken for induction of nanoparticles synthesis by cyanobacterial extracts ranged from 30 to 360 h and their size from 38 to 88 nm. In terms of size Cylindrospermum stagnale NCCU- 104 was the best organism with 38 and 40 nm. But in terms of time Microcheate sp. NCCU- 342 was the best organism as it took 30 h for AgNP synthesis. [ABSTRACT FROM AUTHOR]

• Spherical Cu oxide nanoparticles were prepared in the presence of Calotropis procera as a novel antioxidant and antimicrobial agent. • C. procera extract served as both reducing and capping agent for the bio-synthesis of Cuonps. • Prepared green synthesized Cuonps exhibited significant antimicrobial activities against E.coli and R. oryzae. • C. procera mediated Cuonps showed significant antioxidant activity. Plant mediated nano-fabrication is an emerging field of nanotechnology which is preferred over conventional techniques because of its safety, cost effectiveness, ecofriendliness and biocompatibility properties. The current study includes Calotropis procera mediated synthesis of copper oxide nanoparticles (CuONPs) using aqueous plant extract and their anti-pathogenic activities against phytopathogens. Different microscopic and spectroscopic characterization techniques such as X-ray powder diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), UV–visible spectrophotometer (UV), Scanning electron microscope (SEM) and Transmission electron microscope (TEM) were performed to confirm the biofabrication of Calotropis procera mediated CuONPs. XRD results showed high crystalline nature of the particles ranging from 40 to 100 nm. SEM and TEM images revealed spherical shape and size ranging from 20 to 80 nm. FTIR and UV-visible spectrophotometer confirmed the presence of different functional groups involved in capping, reducing and stabilization of the CuONPs. Moreover, Anti-fungal and anti-bacterial activities were performed which showed maximum inhibition at 100 µg/mL concentration in both in vitro and in detached leaf assay of Muskmelon. In conclusion, our results of greenly synthesized CuONPs showed significant biological potentials and potent antioxidant activity as a result it can be used in phytopathology against plant pathogens. In future, we suggest different other in vitro and in vivo bioactivities using different animal models. [Display omitted] [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa (JQ989348) was isolated from deep sea water sample and used for synthesis of silver nanoparticles (AgNPs). AgNPs were confirmed by analyzing surface plasmon resonance using UV-visible spectrophotometer at 420 nm. Further scanning electron microscope analysis confirmed the range of particle size between 13 and 76 nm and XRD pattern authorizes the anisotropic crystalline nature of AgNPs. Fourier transform infrared spectrum endorsed the presence of high amount of proteins and other secondary metabolites in synthesized AgNPs influence the reduction process and stabilization of nanoparticles. The inhibitory activity of AgNPs was tested against human pathogens showed high activity against Eschericia coli, Vibrio cholerae, Aeromonas sp., and Cornebacterium sp. demonstrating its antimicrobial value against pathogenic diseases. Additionally, biologically synthesized AgNPs have notable anti-biofilm activity against primary biofilm forming bacteria P. aeruginosa and Staphylococcus aureus. The MTT assay method was evaluated using human cervical cancer cells exposed the AgNPs have excellent cytotoxic activity. [ABSTRACT FROM AUTHOR]

The eco-friendly biosynthesis of silver nanoparticles (AgNPs), using starch as reducing agent, was addressed in this work. Starch solutions with three different concentrations (0.5, 1.0, and 1.5% w/v), heated at 90°C for 12 h and stabilized with 100 µL of NaOH 0.1 M were used during the synthesis process. AgNPs were characterized by UV-visible (UV-Vis) spectrophotometry, SEM equipped with energy dispersive spectrometer and TEM. The antibacterial activity of the AgNPs was evaluated on Staphylococcus aureus using the disc diffusion technique (Kirby-Bauer method) relative to enrofloxacin antibiotic. Solutions containing AgNPs developed a yellow color and presented UV-Vis spectra characteristic for AgNPs, with surface plasmon resonance peaks between 411 and 414 nm. Spherical-shape AgNPs were observed by TEM with sizes between 10 and 30 nm. These silver nanoparticles displayed an antimicrobial activity against S. aureus in colloidal state and films. [ABSTRACT FROM AUTHOR]

Silver nanoparticles are increasingly used in various fields of biotechnology and applications in the medicine. Objectives of this study were optimization of production of silver nanoparticles using biotransformations by Fusarium oxysporum, and a further study on the location of nanoparticles synthesis in this microorganism. The reaction mixture contained the following ingredients (final concentrations): AgNO3 (1-10 mM) as the biotransformation substrate, biomass as the biocatalyst, glucose (560 mM) as the electron donor, and phosphate buffer (pH= 7, 100 mM). The samples were taken from the reaction mixtures at different times, and the absorbance (430 nm) of the colloidal suspensions of silver nanoparticles hydrosols was read freshly (without freezing) and immediately after dilution (1:40). SEM and TEM analyses were performed on selected samples. The presence of AgNO3 (0.1 mM) in the culture as enzyme inducer, and glucose (560 mM) as electron donor had positive effects on nanoparticle production. In SEM micrographs, silver nanoparticles were almost spherical, single (25-50 nm) or in aggregates (100 nm), attached to the surface of biomass. The reaction mixture was successfully optimized to increase the yield of silver nanoparticles production. More details of the location of nanoparticles production by this fungus were revealed, which support the hypothesis that silver nanoparticles are synthesized intracellularly and not extracellularly. [ABSTRACT FROM AUTHOR]

UDP-N-acetylglucosamine (UDP-GlcNAc) is a direct glycosyl donor of linker unit (L-Rhamnose-D-GlcNAc) and an essential precursor of peptidoglycan in mycobacteria. Phosphoglucosamine mutase (GlmM) is involved in the formation of glucosamine-1-phosphate from glucosamine-6-phosphate, the second step in UDP-GlcNAc biosynthetic pathway. We have demonstrated that GlmM protein is essential for the growth of M. smegmatis. To facilitate the analysis of the GlmM protein function in mycobacteria, a tetracycline inducible M. smegmatis glmM gene knockdown strain was constructed by using an antisense RNA technology. After induction with 20 ng/ml tetracycline, the expression of GlmM protein in glmM gene knockdown strain was significantly decreased, resulting in a decline of cell growth. The morphological changes of glmM gene knockdown strain induced with 20 ng/ml tetracycline have been observed by scanning electron microscope and transmission electron microscope. Furthermore, insufficient GlmM protein reduced the biofilm formation and increased the sensitivity to isoniazid and ethambutol in M. smegmatis, indicating that GlmM protein had effect on the biofilm formation and the senstivity to some anti-tuberculosis drugs targeting the cell wall. These results provide a new insight on GlmM functions in mycobacteria, suggesting that GlmM could be a potential target for development of new anti-tuberculosis drug. [ABSTRACT FROM AUTHOR]