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1.
In this study the green method for synthesizing selenium nanoparticles (SeNPs) is experienced, in which the leaf extract of Adiantum capillus was used as an effective chelating and capping agent for producing SeNPs. The characterization techniques that achieved to confirm the synthesis and the structure details of the SeNPs were: UV–Vis spectroscopy, FT-IR analysis, XRD, EDX and SEM analysis. The biological activity of the synthesized SeNPs were tested and compared to the crude extract of Adiantum capillus on gentamicin model of nephrotoxicity in Wistar rats. Sera were used to test the pro-inflammatory cytokines Tumor necrosis factor alpha (TNF-α) and Interleukin beta (IL-β) levels. Histopathology and immunohistochemistry analysis for the apoptosis regulator protein (Bcl-2) and the interstitial filament protein (Vimentin) were performed. Results revealed that the synthesized SeNPs peak appeared at 400–430 nm wave length with crystallite particle size is around 37 nm. The predominant shape is spherical and cubic at different magnification levels with a narrow size distribution of 22.04–128.43 nm. The synthesized SeNPs showed a strong protective effect against gentamicin induced toxic effects to the rat’s kidneys obtained from the (kidney function parameters, histopathology evaluation, recovery of the pro-inflammatory cytokines IL-β and TNF-α level with retrieval of Bcl-2 and vimentin protein levels proximate to the vehicle control groups). Due to the significant protective effect of SeNPs, it considered much better than the crude extract of Adiantum capillus in the treatment of kidney injury; however, additional studies are necessary to find the precise mechanism of their action.  相似文献   

2.
近年来,纳米硒凭借其良好的导电、光热以及抗癌等特性,在纳米技术、生物医学以及环境修复等诸多领域得到广泛应用。实验选择前期筛选得到的贪铜杆菌Cupriavidus sp. SHE,文中探究了该菌株的细胞上清液、全细胞以及胞内提取物合成纳米硒的能力,并对细胞上清液合成的纳米硒进行形貌表征与官能团分析,最后选取革兰氏阳性菌假单胞菌Pseudomonas sp. PI1和革兰氏阴性菌大肠杆菌Escherichia coli BL21进行抗菌实验。结果表明,菌株Cupriavidussp.SHE的细胞上清液、全细胞以及胞内提取物均具有合成纳米硒的能力。对于菌株Cupriavidus sp. SHE细胞上清液而言,在该实验中,研究范围内其合成纳米硒的最佳条件是SeO2浓度为5 mmol/L,pH为7。透射电子显微镜结果表明合成的纳米硒颗粒主要为球形,平均直径为196nm。X射线衍射结果表明合成的纳米硒晶体类型为六方形结构。傅立叶转换红外光谱和聚丙烯酰胺凝胶电泳结果表明纳米硒表面有小分子蛋白结合,可能参与了纳米硒的合成和稳定过程。此外,抗菌实验表明菌株Cupriavidus sp. SHE细胞上清液合成的纳米硒颗粒对菌株E.coli BL21和Pseudomonas sp. PI1均无明显的抗菌活性。综上,该研究表明菌株Cupriavidus sp.SHE在细胞上清液中产生的蛋白类物质在其合成纳米硒的过程中发挥了重要作用,合成的生物纳米硒颗粒无毒且生物相容性良好,未来在生物医学等领域具有较好的应用潜力。  相似文献   

3.
Currently, there is an ever-increasing need to develop environmentally benign processes in place of synthetic protocols. As a result, researchers in the field of nanoparticle synthesis are focusing their attention on microbes from rare biological ecosystems. One potential actinobacterium, Streptomyces minutiscleroticus M10A62 isolated from a magnesite mine had the ability to synthesize selenium nanoparticles (SeNPs), extracellularly. Actinobacteria mediated SeNP synthesis were characterized by UV–visible, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX) and high resolution transmission electron microscopy (HR-TEM) analysis. The UV-spectral analysis of SeNPs indicated the maximum absorption at 510 nm, FT-IR spectral analysis confirms the presence of capping protein, peptide, amine and amide groups. The selenium signals confirm the presence of SeNPs. All the diffraction peaks in the XRD pattern and HR-TEM confirm the size of SeNPs in the range of 10–250 nm. Further, the anti-biofilm and antioxidant activity of the SeNPs increased proportionally with rise in concentration, and the test strains reduced to 75% at concentration of 3.2 μg. Selenium showed significant anti-proliferative activity against HeLa and HepG2 cell lines. The wound healing activity of SeNPs reveals that 5% selenium oinment heals the excision wound of Wistar rats up to 85% within 18 days compared to the standard ointment. The biosynthesized SeNPs exhibited good antiviral activity against Dengue virus. The present study concludes that extremophilic actinobacterial strain was a novel source for SeNPs with versatile biomedical applications and larger studies are needed to quantify these observed effects of SeNPs.  相似文献   

4.
Tailored nanoparticles offer a novel approach to fight antibiotic‐resistant microorganisms. We analysed biogenic selenium nanoparticles (SeNPs) of bacterial origin to determine their antimicrobial activity against selected pathogens in their planktonic and biofilm states. SeNPs synthesized by Gram‐negative Stenotrophomonas maltophilia [Sm‐SeNPs(?)] and Gram‐positive Bacillus mycoides [Bm‐SeNPs(+)] were active at low minimum inhibitory concentrations against a number of clinical isolates of Pseudomonas aeruginosa but did not inhibit clinical isolates of the yeast species Candida albicans and C. parapsilosis. However, the SeNPs were able to inhibit biofilm formation and also to disaggregate the mature glycocalyx in both P. aeruginosa and Candida spp. The Sm‐SeNPs(?) and Bm‐SeNPs(+) both achieved much stronger antimicrobial effects than synthetic selenium nanoparticles (Ch‐SeNPs). Dendritic cells and fibroblasts exposed to Sm‐SeNPs(?), Bm‐SeNPs(+) and Ch‐SeNPs did not show any loss of cell viability, any increase in the release of reactive oxygen species or any significant increase in the secretion of pro‐inflammatory and immunostimulatory cytokines. Biogenic SeNPs therefore appear to be reliable candidates for safe medical applications, alone or in association with traditional antibiotics, to inhibit the growth of clinical isolates of P. aeruginosa or to facilitate the penetration of P. aeruginosa and Candida spp. biofilms by antimicrobial agents.  相似文献   

5.
This study presents a special, economically valuable, unprecedented eco-friendly green process for the synthesis of silver nanoparticles. The silver nanoparticles were obtained from a waste material with oil palm biosolid extract as the reducing agent. The use of the oil palm biosolid extract for the nanoparticle synthesis offers the benefit of amenability for large-scale production. An aqueous solution of silver (Ag(+) ) ions was treated with the oil palm biosolid extract for the formation of Ag nanoparticles. The nanometallic dispersion was characterized by surface plasmon absorbance measuring 428 nm. Transmission electron microscopy showed the formation of silver nanoparticles in the range of 5-50 nm. Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction analysis of the freeze-dried powder confirmed the formation of metallic silver nanoparticles. Moreover, Fourier Transform Infrared Spectroscopy provided evidence of phenolics or proteins as the biomolecules that were likely responsible for the reduction and capping agent, which helps to increase the stability of the synthesized silver nanoparticles. In addition, we have optimized the production with various parameters.  相似文献   

6.
The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.  相似文献   

7.
BackgroundSelenium has a major role in male reproduction and antioxidative mechanisms. Although deficiency of this element can result in damages to the body's organs, this metalloid can induce deleterious effects in organisms by causing oxidative stress. This study assessed the spermatotoxicity of selenium nanoparticles (SeNPs) in goldfish (Carassius auratus) based on genotoxicity, antioxidant status, sperm quality, and histopathology.MethodsThe fish with an average weight of 70 g (n = 288) were divided into four experimental groups (three replicates) and fed three times a day with SeNPs at different levels of 0, 0.1, 0.5, and 1 mg kg diet for 30 and 60 days.ResultsAfter 30 and 60 days of feeding trial, compared to the control group, spermatocrit percentage markedly decreased at 1 mg kg SeNPs on day 30 as well as at 0.5 and 1 mg kg on day 60 (p < 0.05). Computer-assisted sperm analysis parameters especially VCL, VSL, and VAP decreased in response to SeNPs (p < 0.05). Percentage of fast speed progressive sperm cells was highest in fish fed with 0.1 mg kg SeNPs following the dietary experiment and significantly reduced in a SeNPs dose-dependent manner (p < 0.05). In addition, the levels of Malondialdehyde and Glutathione peroxidase were significantly elevated in seminal plasma of all SeNPs-treated groups (p < 0.05). On day 60, DNA damage of sperm was greatly increased at 1 mg kg SeNPs (p < 0.05). Moreover, the highest percentage of spermatocyte and spermatid were observed at the highest dose of SeNPs while the highest percentage of spermatozoa was recorded at the lowest and moderate SeNPs doses.ConclusionThese findings suggested that non-optimal doses of SeNPs could reduce sperm quality, induce oxidative stress, and DNA damage in sperm, and disrupt testis development.  相似文献   

8.
Green synthesis of selenium nanoparticles (SeNPs) was achieved by a simple biological procedure using the reducing power of fenugreek seed extract. This method is capable of producing SeNPs in a size range of about 50–150 nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous sols by a high-speed centrifuge. These selenium nanoparticles were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and elemental analysis by X-ray fluorescence spectrometer (XRF). Nanocrystalline SeNPs were obtained without post-annealing treatment. FTIR spectrum confirms the presence of various functional groups in the plant extract, which may possibly influence the reduction process and stabilization of nanoparticles. The cytotoxicity of SeNPs was assayed against human breast-cancer cells (MCF-7). It was found that SeNPs are able to inhibit the cell growth by dose-dependent manner. In addition, combination of SeNPs and doxorubicin shows better anticancer effect than individual treatments.  相似文献   

9.
In the present study copper oxide nanoparticles (CuONPs) were synthesized via simple and eco-friendly green route using leaf extract of Enicostemma axillare (Lam.). Characterization of synthesized nanoparticles (NPs) was undertaken. The characteristic absorption peak of CuONPs was in range 264nm in UV–Vis spectrum. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies revealed the morphological and structural character of green NPs. The mean particle size was calculated to 30nm. Energy dispersive spectroscopy (EDS) showed high intense metallic peak of copper (Cu), oxygen (O) and low intense peaks of carbon (C), sulfur (S), phosphorus (P) elements due to the capping action of biomolecules of plant extract in CuONPs formation. The X-ray diffraction (XRD) pattern showed distinctive peaks corresponding to (200), (211) and (310) planes revealing the high crystalline nature of synthesized CuONPs with a primitive phase. Zeta potential and size distribution of synthesized green NPs was concluded by Dynamic light scattering (DLS) studies.  相似文献   

10.
Silver nanoparticles (AgNPs), manganese dioxide nanoparticles (MnO2NPs) and silver-doped manganese dioxide nanoparticles (Ag-doped MnO2NPs) were synthesized by simultaneous green chemistry reduction approach. Aqueous extract from the leaves of medicinally important plant Cucurbita pepo was used as reducing and capping agents. Various characterization techniques were carried out to affirm the formation of nanoparticles. HR-TEM analysis confirmed the size of nanoparticles in the range of 15–70 nm and also metal doping was confirmed through XRD and EDS analyses. FT-IR analysis confirmed that the presence of biomolecules in the aqueous leaves extract was responsible for nanoparticles synthesis. Further, the concentration of metals and their doping in the reaction mixture was achieved by ICP–MS. The growth curve and well diffusion study of synthesized nanoparticles were performed against food- and water-borne Gram-positive and Gram-negative bacterial pathogens. The mode of interaction of nanoparticles on bacterial cells was demonstrated through Bio-TEM analysis. Interestingly, AgNPs and Ag-doped MnO2 NPs showed better antibacterial activity against all the tested bacterial pathogens; however, MnO2NPs alone did not show any antibacterial properties. Hence, AgNPs and Ag-doped MnO2 NPs synthesized from aqueous plant leaves extract may have important role in controlling various food spoilage caused by bacteria.  相似文献   

11.
This study investigated the antimicrobial and antioxidant activity of three Spirulina extracts (methanol, acetone, and hexane) and the biological selenium nanoparticles (SeNPs) fabricated by Bacillus subtilis AL43. The results showed that Spirulina extracts exhibited antimicrobial activity against tested pathogens. Besides, Spirulina extracts significantly scavenged ABTS and DPPH radicals in a dose-dependent manner. The methanolic extract had higher total phenolic content, antimicrobial activity, and antioxidant activity than other extracts. The selenium nanoparticles were synthesized by Bacillus subtilis AL43 under aerobic conditions and were characterized as spherical, crystalline with a size of 65.23 nm and a net negative charge of ?22.7. We evidenced that SeNPs possess considerable antimicrobial activity against three gram-positive, three gram-negative bacteria, and three strains from both Candida sp. and Aspergillus sp. Moreover, SeNPs were able to scavenge ABTS and DPPH radicals in a dose-dependent manner. An association was found between the total phenolic content of Spirulina and SeNPs and their biological activities. Our results indicate that Spirulina and SeNPs with significant antimicrobial and antioxidant activities seem to be successful candidates for safe and reliable medical applications.  相似文献   

12.
Alcoholic cardiomyopathy is the damage caused to the heart muscles due to high level of alcohol consumption resulting in enlargement and inflammation of the heart. Selenium is an important trace element that is beneficial to human health. Selenium protects the cells by preventing the formation of free radicals in the body. In the present study, protein mediated synthesis of SeNPs was investigated. Two different sizes of SeNPs were synthesized using BSA and keratin. The synthesized SeNPs were characterized by scanning electron microscopy (SEM) with elemental composition analysis Energy Dispersive X-ray spectroscopy(EDX) and X-ray diffraction (XRD). This study demonstrates the in vitro and in vivo antioxidative effects of sodium selenite and SeNPs. Further selenium and SeNPs were evaluated for their ability to protect against 1% ethanol induced oxidative stress in H9C2 cell line. The selenium and SeNPs were found to reduce the 1% ethanol-induced oxidative damage through scavenging intracellular reactive oxygen species. The selenium and SeNPs could also prevent pericardial edema induced ethanol treatment and reduced apoptosis and cell death in zebrafish embryos. The results indicate that selenium and SeNPs could potentially be used as an additive in alcoholic beverage industry to control the cardiomyopathy.  相似文献   

13.
The aim of this study was to biosynthesis silver nanoparticles from the fungus Nigrospora sphaerica isolated from soil samples and to examine their activity against five human pathogenic strains of bacteria viz. Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella typhi and Staphylococcus aureus using disc diffusion method. The synergistic effect of silver nanoparticles in combination with commonly used antibiotic Gentamycin against the selected bacteria was also examined. The synthesized silver nanoparticles from free-cell filtrate were characterized by using UV–Vis spectrophotometer analysis, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). UV–Vis spectrophotometer analysis showed a peak at 420 nm indicating the synthesis of silver nanoparticles, FTIR analysis verified the detection of protein capping of silver nanoparticles while SEM micrographs revealed that the silver nanoparticles are dispersed and aggregated and mostly having spherical shape within the size range between 20 and 70 nm. The synthesized silver nanoparticles exhibited a varied growth inhibition activity (15–26 mm diam inhibition zones) against the tested pathogenic bacteria. A remarkable increase of bacterial growth inhibition (26–34 mm diam) was detected when a combination of silver nanoparticles and Gentamycin was used. A significant increase in fold area of antibacterial activity was observed when AgNPs in combination with Gentamycin was applied. The synthesized silver nanoparticles produced by the fungus N. sphaerica is a promising to be used as safe drug in medical therapy due to their broad spectrum against pathogenic bacteria.  相似文献   

14.
Biological efficiency of existing antimicrobial agents is still inadequate to ensure optimal therapeutic index. Developing biocompatible advanced functional materials with antimicrobial properties could be promising for environmentally benign applications. Nanoparticles and other nanoscale materials are of great interest due to their multiple potential applications in material science, medicine, and industry. Nanomaterials possess well renowned antimicrobial activity against several microorganisms; however, it has some non-specific toxicity. Biofunctionalization of nanomaterials is one such topic to address this issue. Rational selection of therapeutically active biomolecules for design of nanoparticles will certainly increase the biological applicability. The present paper describes the current status of different types of biofunctionalized nanoparticles and their antibacterial applications. Key principles such as strategies involved at bio-/nanointerface, the structural activity relationship, and mechanism of action involved in the antibacterial activity of functionalized nanoparticles are briefly discussed. This knowledge is important from the objective of generation of advanced functional nanomaterials with antimicrobial properties.  相似文献   

15.
A water-soluble polythiophene, POWT, with zwitterionic peptide like side chains possess good characteristics for biosensor applications. The zwitterionic side chains of the polymer can couple to biomolecules via electrostatic and hydrogen bonding. This creates possibilities to imprint biomolecules to spin-coated polymer films with maintained functionality, and use the resulting matrix as a biosensor. Polymer-biomolecular interaction studies done with surface plasmon resonance (SPR) reveal a well performing sensor matrix with high affinity for DNA hybridizations as well as for protein detection. The responses are distinct and very specific. A directional dependence of antibodies binding to POWT layer has also been observed. The polymer films have also been characterized by optical methods. Emission and absorption measurements in different buffer systems confirm that the polymer matrix can undergo structural and conformational changes on surfaces. The dielectric function in the interval 300-800 nm of POWT is reported, based on variable angle spectroscopic ellipsometry. This modeling reveals that a considerable amount of water is included in the material. The polymer layer possesses the characteristics needed for biochip applications and micro array techniques.  相似文献   

16.
The present study deals with isolation and characterization of copper oxide nanoparticles resistant Pseudomonas strains that were isolated from the soil collected from mining and refining sites of Sarcheshmeh copper mine in the Kerman Province of Iran. The three isolates were selected based on high level of copper oxide nanoparticles (CuO NPs) resistance. The isolates were authentically identified as Pseudomonas fluorescens CuO-1, Pseudomonas fluorescens CuO-2 and Pseudomonas sp. CuO-3 by morphological, biochemical and 16S rDNA gene sequencing analysis. The growth pattern of these isolates with all the studied CuO NPs concentrations was similar to that of control (without CuO NPs) indicating that CuO NPs would not affect the growth of isolated strains. A reduction in the amount of exopolysaccharides was observed after CuO NPs—P. fluorescens CuO-1 culture supernatant interaction. The Fourier transform infrared spectroscopy (FT-IR) peaks for the exopolysaccharides extracted from the bacterial culture supernatant and the interacted CuO NPs were almost similar. The exopolysaccharide capping of the CuO NPs was confirmed by FT-IR and X-ray diffraction analysis. The study of bacterial exopolysaccharides capped CuO NPs with E. coli PTCC 1338 and S. aureus PTCC 1113 showed less toxicity compared to uncoated CuO NPs. Our study suggests that the capping of nanoparticles by bacterially produced exopolysaccharides serve as the probable mechanism of tolerance.  相似文献   

17.
Phytochelatins (PCs) are metal-binding cysteine-rich peptides, enzymatically synthesized in plants and yeasts from glutathione in response to heavy metal stress by PC synthase (EC 2.3.2.15). In an attempt to increase the ability of bacterial cells to accumulate heavy metals, the Arabidopsis thaliana gene encoding PC synthase (AtPCS) was expressed in Escherichia coli. A marked accumulation of PCs was observed in vivo together with a decrease in the glutathione cellular content. When bacterial cells expressing AtPCS were placed in the presence of heavy metals such as cadmium or the metalloid arsenic, cellular metal contents were increased 20- and 50-fold, respectively. We discuss the possibility of using genes of the PC biosynthetic pathway to design bacterial strains or higher plants with increased abilities to accumulate toxic metals, and also arsenic, for use in bioremediation and/or phytoremediation processes.  相似文献   

18.
Nanoparticles synthesis by bacteria and yeasts has been widely reported, however, synthesis using halophilic archaea is still in a nascent stage. This study aimed at the intracellular synthesis of selenium nanoparticles (SeNPs) by the haloarchaeon Halococcus salifodinae BK18 when grown in the presence of sodium selenite. Crystallographic characterization of SeNPs by X‐ray diffraction, Selected area electron diffraction, and transmission electron microscopy exhibited rod shaped nanoparticles with hexagonal crystal lattice, a crystallite domain size of 28 nm and an aspect ratio (length:diameter) of 13:1. Energy disruptive analysis of X‐ray analysis confirmed the presence of selenium in the nano‐preparation. The nitrate reductase enzyme assay and the inhibitor studies indicated the involvement of NADH‐dependent nitrate reductase in SeNPs synthesis and metal tolerance. The SeNPs exhibited good anti‐proliferative properties against HeLa cell lines while being non‐cytotoxic to normal cell line model HaCat, suggesting the use of these SeNPs as cancer chemotherapeutic agent. This is the first study on selenium nanoparticles synthesis by haloarchaea. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1480–1487, 2014  相似文献   

19.
The present study explores the reducing and capping potentials of ethanolic flower extract of the plant Nyctanthes arbortristis for the synthesis of gold nanoparticles. The extract at different volume fractions were stirred with HAuCl4 aqueous solution at 80 °C for 30 min. The UV–Vis spectroscopic analysis of the reaction products confirmed successful reduction of Au3+ ions to gold nanoparticles. Transmission electron microscope (TEM) revealed dominant spherical morphology of the gold nanoparticles with an average diameter of 19.8 ± 5.0 nm. X-ray diffraction (XRD) study confirmed crystalline nature of the synthesized particles. Fourier transform infra-red (FTIR) and nuclear magnetic resonance (NMR) analysis of the purified and lyophilized gold nanoparticles confirmed the surface adsorption of biomolecules during preparation and caused long-term (6 months) stability. Low reaction temperature (25 °C) favored anisotropy. The strong reducing power of the flower extract can also be tested in the green synthesis of other metallic nanoparticles.  相似文献   

20.
Due to their less expensive, environment friendly nature, and their natural abundance of cobalt have attained more significant attention for the synthesis of cobalt nanoparticles. In the present study, we report the facile synthesis of cobalt nanoparticles using a straight forward chemical reduction approach of cobalt chloride with sodium borohydride and capping of sulfadimidine. sulfadimidine has strong capping eligibility on the surface of nanoparticles due to its chemical stability and is an applicable as stabilizer due to the existence of an amine bond. The as-synthesized sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were characterized by using various spectroscopic and microscopic analysis like UV–Visible spectroscopy (UV–Vis), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), High-Resolution Transmission electron microscopy (HR-TEM), and Fourier-transform infrared spectroscopy (FT-IR). The XRD analysis exhibited the triclinic crystal structure of the as-synthesized cobalt nanoparticles and FT-IR analysis confirmed the capping of sulfadimidine via monodentate interaction. The HR-TEM analysis displayed the size of the cobalt nanoparticles approximately 3–5 nm. The antibacterial properties of the sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were tested against various bacterial strains such as Klebsiella pneumonia (KP), Escherichia coli (EC) and Pseudomonas syringae (PS) by using agar disc diffusion approach. The results of sulfadimidine capped cobalt nanoparticles displayed the enhanced biological properties against the tested gram-negative bacteria.  相似文献   

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