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1.
Microb Cell Fact ; 23(1): 220, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107838

RESUMO

BACKGROUND: Biotechnology provides a cost-effective way to produce nanomaterials such as silver oxide nanoparticles (Ag2ONPs), which have emerged as versatile entities with diverse applications. This study investigated the ability of endophytic bacteria to biosynthesize Ag2ONPs. RESULTS: A novel endophytic bacterial strain, Neobacillus niacini AUMC-B524, was isolated from Lycium shawii Roem. & Schult leaves and used to synthesize Ag2ONPS extracellularly. Plackett-Burman design and response surface approach was carried out to optimize the biosynthesis of Ag2ONPs (Bio-Ag2ONPs). Comprehensive characterization techniques, including UV-vis spectral analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray diffraction, dynamic light scattering analysis, Raman microscopy, and energy dispersive X-ray analysis, confirmed the precise composition of the Ag2ONPS. Bio-Ag2ONPs were effective against multidrug-resistant wound pathogens, with minimum inhibitory concentrations (1-25 µg mL-1). Notably, Bio-Ag2ONPs demonstrated no cytotoxic effects on human skin fibroblasts (HSF) in vitro, while effectively suppressing the proliferation of human epidermoid skin carcinoma (A-431) cells, inducing apoptosis and modulating the key apoptotic genes including Bcl-2 associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), Caspase-3 (Cas-3), and guardian of the genome (P53). CONCLUSIONS: These findings highlight the therapeutic potential of Bio-Ag2ONPs synthesized by endophytic N. niacini AUMC-B524, underscoring their antibacterial efficacy, anticancer activity, and biocompatibility, paving the way for novel therapeutic strategies.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Compostos de Prata , Humanos , Nanopartículas Metálicas/química , Compostos de Prata/farmacologia , Compostos de Prata/química , Antibacterianos/farmacologia , Antibacterianos/biossíntese , Testes de Sensibilidade Microbiana , Bacillaceae/metabolismo , Óxidos/farmacologia , Óxidos/química , Fibroblastos/efeitos dos fármacos , Apoptose/efeitos dos fármacos
2.
Biometals ; 37(4): 971-982, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38409305

RESUMO

The 'sacred leaf' or "Hoja Santa" (Piper auritum Kunth) has a great value for Mexican culture and has gained popularity worldwide for its excellent properties from culinary to remedies. To contribute to its heritage, in this project we proposed the green synthesis of silver oxide nanoparticles (Ag2O NPs) using an extract of "Hoja Santa" (Piper auritum) as a reducing and stabilizing agent. The synthesized Ag2O NPs were characterized by UV-Visible spectroscopy (plasmon located at 405 nm), X-ray diffraction (XRD) (particle size diameter of 10 nm), scanning electron microscopy (SEM) (particle size diameter of 13.62 ± 4.61 nm), and Fourier-transform infrared spectroscopy (FTIR) (functional groups from "Hoja Santa" attached to nanoparticles). Antioxidant capacity was evaluated using DPPH, ABTS and FRAP methods. Furthermore, the antimicrobial activity of NPs against a panel of clinically relevant bacterial strains, including both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Salmonella Enteritidis and Escherichia coli O157:H7), was over 90% at concentrations of 200 µg/mL. Additionally, we assessed the antibiofilm activity of the NPs against Pseudomonas aeruginosa (reaching 98% of biofilm destruction at 800 µg/mL), as biofilm formation plays a crucial role in bacterial resistance and chronic infections. Moreover, we investigated the impact of Ag2O NPs on immune cell viability, respiratory burst, and phagocytic activity to understand their effects on the immune system.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Piper , Extratos Vegetais , Compostos de Prata , Staphylococcus aureus , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Compostos de Prata/química , Compostos de Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Piper/química , Nanopartículas Metálicas/química , Óxidos/química , Óxidos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Animais , Camundongos , Salmonella enteritidis/efeitos dos fármacos , Tamanho da Partícula , Células RAW 264.7 , Escherichia coli O157/efeitos dos fármacos , Folhas de Planta/química
3.
Int J Mol Sci ; 24(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36614309

RESUMO

Foodborne infections are an important global health problem due to their high prevalence and potential for severe complications. Bacterial contamination of meat during processing at the enterprise can be a source of foodborne infections. Polymeric coatings with antibacterial properties can be applied to prevent bacterial contamination. A composite coating based on fluoroplast and Ag2O NPs can serve as such a coating. In present study, we, for the first time, created a composite coating based on fluoroplast and Ag2O NPs. Using laser ablation in water, we obtained spherical Ag2O NPs with an average size of 45 nm and a ζ-potential of -32 mV. The resulting Ag2O NPs at concentrations of 0.001-0.1% were transferred into acetone and mixed with a fluoroplast-based varnish. The developed coating made it possible to completely eliminate damage to a Teflon cutting board. The fluoroplast/Ag2O NP coating was free of defects and inhomogeneities at the nano level. The fluoroplast/Ag2O NP composite increased the production of ROS (H2O2, OH radical), 8-oxogualnine in DNA in vitro, and long-lived active forms of proteins. The effect depended on the mass fraction of the added Ag2O NPs. The 0.01-0.1% fluoroplast/NP Ag2O coating exhibited excellent bacteriostatic and bactericidal properties against both Gram-positive and Gram-negative bacteria but did not affect the viability of eukaryotic cells. The developed PTFE/NP Ag2O 0.01-0.1% coating can be used to protect cutting boards from bacterial contamination in the meat processing industry.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Antibacterianos/farmacologia , Politetrafluoretileno , Peróxido de Hidrogênio , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Bactérias , Carne
4.
Nanotechnology ; 33(40)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35767930

RESUMO

Alternating current electroluminescent (AC-EL) device can be considered as a potential candidate for next generation of multifunctional light-emitting sources. In this work, we present a new design of AC-EL device with inclusion of a silver oxide humidity-sensing layer instead of an insulating buffer layer for humidity detection. The ZnS:Cu, Cl and ZnS:Ag+(Zn,Cd)S:Ag phosphors were used as an emissive layer prepared by screen printing method. The silver oxide (AgO/Ag2O) nanoparticles synthesized via a green method were employed as a humidity sensing layer. The developed AC-EL devices exhibited high response, good productivity, high stability, high repeatability and linear relationship with humidity in range of 10%-90% RH as well as no significant effects with several VOCs/gases such as NH3, CO2, acetone, methanol, toluene and propan at room temperature. The effects of parameters such as excitation frequency, applied voltage, and waveforms on the luminance intensity are discussed. The development of the present AC-EL device offers a simplified architecture to enable sensing functions of the AC-EL device via monitoring of light emission changing.

5.
Int J Environ Health Res ; 32(3): 616-627, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32627584

RESUMO

As therapeutic antiviral agents, biological nanoparticles can fight the drug-resistant types of viruses helping the antiviral drug development. In this study, two blue-green algal strains; Oscillatoria sp. and Spirulina platensis were used, mediated by green Ag2O|AgO-NPs and Au-NPs, respectively. For NPs characterization, the UV/Vis spectroscopy were used where their formation and crystallinity were proven with λmax values for silver and gold NPs of 432 and 552 nm, respectively. The transmission electron microscope (TEM) X-ray diffraction showed a spherical-shaped Ag2O|AgO-NPs (size; 14.42 to 48.97) while Au-NPs appeared with octahedral, pentagonal and triangular structures (size; 15.60-77.13 nm). The reducing, capping, and stabilization activities of algal polysaccharides and proteins were indicated via FTIR spectroscopy. Both Ag2O|AgO-NPs and Au-NPs were investigated against Herpes Simplex virus (HSV-1) that has been indicated by its reduction activity of cytopathic effect (CPE). Cytotoxicity was evaluated on Vero cells and measured by MTT assay. Results showed a 90% reduction in CPE of HSV-1 applying Ag2O|AgO-NPs, and Au-NPs at 31.25 µL., with a high reduction rate (49.23%) with Ag2O|AgO-NPs than that of Au-NPs (42.75%). Current results proved the efficiency of green nanotechnology application with both Ag2O|AgO-NPs, and Au-NPs as reducing and inhibitory agents for the HSV-1 replication.


Assuntos
Herpesvirus Humano 1 , Nanopartículas Metálicas , Animais , Antivirais/farmacologia , Chlorocebus aethiops , Técnicas de Cultura , Ouro , Prata , Células Vero
6.
Mol Biol Rep ; 48(12): 7933-7946, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34655404

RESUMO

BACKGROUND: There is an emergency need for the natural therapeutic agents to treat arious life threatening diseases such as cardio- vascular disease, Rheumatoid arthritis and cancer. Among these diseases, cancer is found to be the second life threatening disease; in this view the present study focused to synthesize the silver oxide nanoparticles (AgONPs) from endophytic fungus. METHODS: The endophytic fungus was isolated from a medicinal tree Aegle marmelos (Vilva tree) and the potential strain was screened through antagonistic activity. The endophytic fungus was identified through microscopic (Lactophenol cotton blue staining and spore morphology in culture media) and Internal Transcribed Spacer (ITS) 1, ITS 4 and 18S rRNA amplification. The endophyte was cultured for the synthesis of AgONPs and the synthesized NPs were characterized through UV- Vis, FT- IR, EDX, XRD and SEM. The synthesized AgONPs were determined for antimicrobial, antioxidant and anti- angiogenic activity. RESULTS: About 35 pigmented endophytic fungi were isolated, screened for antagonistic activity against 12 pathogens and antioxidant activity through DPPH radical scavenging assay; among the isolates, FC36AY1 explored the highest activity and the strain FC36AY1 was identified as Aspergillus terreus. The AgONPs were synthesized from the strain FC36AY1 and characterized for its confirmation, functional groups, nanostructures with unit cell dimensions, size and shape, presence of elements through UV-Vis spectrophotometry, FT-IR, XRD, SEM with EDX analysis. The myco-generated AgONPs manifested their antimicrobial and antioxidant properties with maximum activity at minimum concentration. Moreover, the inhibition of angiogenesis by the AgONPs in Hen's Egg Test on the Chorio-Allantoic Membrane analysis were tested on the eggs of Chittagong breed evinced at significant bioactivity least concentration at 0.1 µg/mL. CONCLUSIONS: Thus, the results of this study revealed that the fungal mediated AgONPs can be exploited as potential in biomedical applications.


Assuntos
Aspergillus/metabolismo , Nanopartículas Metálicas/química , Óxidos/química , Compostos de Prata/química , Inibidores da Angiogênese/farmacologia , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Aspergillus/enzimologia , Embrião de Galinha/efeitos dos fármacos , Endófitos/metabolismo , Testes de Sensibilidade Microbiana/métodos , Óxidos/farmacologia , Compostos de Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
7.
Ceram Int ; 47(3): 2917-2948, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32994658

RESUMO

Nanomedicine has seen a significant rise in the development of new research tools and clinically functional devices. In this regard, significant advances and new commercial applications are expected in the pharmaceutical and orthopedic industries. For advanced orthopedic implant technologies, appropriate nanoscale surface modifications are highly effective strategies and are widely studied in the literature for improving implant performance. It is well-established that implants with nanotubular surfaces show a drastic improvement in new bone creation and gene expression compared to implants without nanotopography. Nevertheless, the scientific and clinical understanding of mixed oxide nanotubes (MONs) and their potential applications, especially in biomedical applications are still in the early stages of development. This review aims to establish a credible platform for the current and future roles of MONs in nanomedicine, particularly in advanced orthopedic implants. We first introduce the concept of MONs and then discuss the preparation strategies. This is followed by a review of the recent advancement of MONs in biomedical applications, including mineralization abilities, biocompatibility, antibacterial activity, cell culture, and animal testing, as well as clinical possibilities. To conclude, we propose that the combination of nanotubular surface modification with incorporating sensor allows clinicians to precisely record patient data as a critical contributor to evidence-based medicine.

8.
Molecules ; 25(10)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414219

RESUMO

The present study aimed to explore the eco-friendly synthesis of prism-like silver oxide nanoparticles (Ag2ONPs) from nappa cabbage extract and its p-nitrophenol sensing activity. The prepared Ag2ONPs were characterized by X-ray diffraction (XRD), field-emission scanning spectroscopy (FESEM), energy-dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and ultraviolet (UV)-visible light spectral analysis (UV-Vis). p-Nitrophenol sensing properties of the prepared nanoparticles were also determined using a simple I-V method. The results showed that the as-prepared Ag2ONPs have a face-centered cubic (fcc) crystalline nature and a prism-like morphology with particle size in the range 21.61-92.26 nm. The result also showed a high intensity of the (111) facet, making the Ag2ONP-carbon black/nickel foam electrode (Ag2ONP-C/NFE) exhibit a high-performance response to p-nitrophenol spanning a wide range of concentrations from 1.0 mM to 0.1 pM and a response time of around 5 s, indicating a high potential for water treatment applications.


Assuntos
Brassica napus/química , Nanopartículas/química , Nitrobenzenos/análise , Óxidos/química , Extratos Vegetais/química , Compostos de Prata/química , Nanopartículas/ultraestrutura , Tamanho da Partícula
9.
Inflammopharmacology ; 26(4): 1025-1035, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29204780

RESUMO

Silver and silver oxides are gaining interest in medical applications for their prominent antibacterial and antimicrobial potentials. Recent studies suggest that nanosilver oxide has remarkable anti-inflammatory effects and enhances wound healing. Nevertheless, its effect on gastric ulcer has not yet been illustrated. Thus the current study aimed to explore the prospect protective effect of nanosilver oxide against indomethacin-induced gastric ulcer. A new approach has been followed to synthesize nanosilver oxide. X-ray diffraction, UV-Vis spectroscopy and transition electron microscope techniques have been successfully used to characterize the synthesized nanoparticles. Treatment of ulcerated rats with different doses of nanosilver oxide especially (175 and 350 ppm/p.o.) alleviated adverse effects of indomethacin-induced gastric injury as demonstrated by decreasing ulcer index and elevating % of ulcer inhibition. These positive effects excelled those exerted by the reference antiulcer drug omeprazole. Nanosilver oxide suppressed gastric inflammation by reducing myeloperoxidase, tumor necrosis alpha, interleukin 1beta and interferon gamma. Moreover, nanosilver oxide halted gastric oxidative stress via inhibiting lipid  peroxidation and enhancing glutathione and paraoxonase-1. Regarding gastric apoptosis, nanosilver oxide down regulated the expression of caspase 9, tumor protein 53, and nuclear factor kappa B and allograft inflammatory factor-1 genes. These findings emphasize the antiulcerogenic potential of nanosilver oxide against indomethacin-induced gastric ulcers which are multi-factorial including anti-inflammatory, antioxidant and antiapoptotic effects.


Assuntos
Antiulcerosos/farmacologia , Nanopartículas Metálicas , Óxidos/farmacologia , Compostos de Prata/farmacologia , Úlcera Gástrica/prevenção & controle , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/toxicidade , Antiulcerosos/administração & dosagem , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Indometacina/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Óxidos/administração & dosagem , Ratos , Ratos Wistar , Compostos de Prata/administração & dosagem , Úlcera Gástrica/induzido quimicamente , Difração de Raios X
10.
Chemotherapy ; 62(5): 279-289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28490010

RESUMO

BACKGROUND: Development of novel strategies to kill cancer by sparing normal cells is of utmost importance. Apart from their known antimicrobial activity, only limited information has been recorded regarding the antitumor potential of biocompatible silver oxide nanoparticles (AgONPs). There is a need to evaluate the anticancer potential of biocompatible AgONPs in vitro. METHODS: A new approach of utilizing the leaf extract of Excoecaria agallocha was used to synthesize AgONPs. This was then characterized by ultraviolet-visible spectrophotometry, nanoparticle-tracking analysis, and ζ-potential analysis. Cytotoxicity and apoptotic potential were evaluated with an MTT assay and an annexin V-binding assay against the murine melanoma (B16F10), murine colon cancer (CT26), murine lung adenocarcinoma (3LL), and murine Ehrlich ascites carcinoma (EAC) cell lines. Cellular localization of AgONPs was evaluated on fluorescence microscopy. RESULTS: UV peaks at 270 and 330 nm indicated the formation of nanoparticles (NPs) and the NP-tracking analyzer revealed them to have a size of 228 nm. AgONPs exerted initial cytotoxicity, specifically against all the experimental malignant cells by sparing the normal cell lines. Moreover, AgONPs exert apoptosis equally on all the malignant cells in vitro and ex vivo. This cytotoxicity possibly occurs via the nuclear translocation of AgONPs as analyzed in B16F10 cells. CONCLUSIONS: AgONPs utilizing natural sources would be a new medicinal approach against a broad spectrum of malignancy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas/química , Óxidos/química , Extratos Vegetais/farmacologia , Compostos de Prata/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Euphorbiaceae/química , Euphorbiaceae/metabolismo , Química Verde , Humanos , Camundongos , Microscopia Confocal , Tamanho da Partícula , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo
11.
Sci Rep ; 14(1): 10484, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714767

RESUMO

The current research aimed to study the green synthesis of silver oxide nanoparticles (AgONPs) using Rhynchosia capitata (RC) aqueous extract as a potent reducing and stabilizing agent. The obtained RC-AgONPs were characterized using UV, FT-IR, XRD, DLS, SEM, and EDX to investigate the morphology, size, and elemental composition. The size of the RC-AgONPs was found to be ~ 21.66 nm and an almost uniform distribution was executed by XRD analysis. In vitro studies were performed to reveal biological potential. The AgONPs exhibited efficient DPPH free radical scavenging potential (71.3%), reducing power (63.8 ± 1.77%), and total antioxidant capacity (88.5 ± 4.8%) to estimate their antioxidative power. Antibacterial and antifungal potentials were evaluated using the disc diffusion method against various bacterial and fungal strains, and the zones of inhibition (ZOI) were determined. A brine shrimp cytotoxicity assay was conducted to measure the cytotoxicity potential (LC50: 2.26 µg/mL). In addition, biocompatibility tests were performed to evaluate the biocompatible nature of RC-AgONPs using red blood cells, HEK, and VERO cell lines (< 200 µg/mL). An alpha-amylase inhibition assay was carried out with 67.6% inhibition. Moreover, In vitro, anticancer activity was performed against Hep-2 liver cancer cell lines, and an LC50 value of 45.94 µg/mL was achieved. Overall, the present study has demonstrated that the utilization of R. capitata extract for the biosynthesis of AgONPs offers a cost-effective, eco-friendly, and forthright alternative to traditional approaches for silver nanoparticle synthesis. The RC-AgONPs obtained exhibited significant bioactive properties, positioning them as promising candidates for diverse applications in the spheres of medicine and beyond.


Assuntos
Nanopartículas Metálicas , Compostos de Prata , Nanopartículas Metálicas/química , Animais , Humanos , Compostos de Prata/química , Compostos de Prata/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Artemia/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Química Verde/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Células Vero , Antifúngicos/farmacologia , Antifúngicos/química , Prata/química , Prata/farmacologia , Óxidos
12.
ACS Appl Mater Interfaces ; 15(42): 48978-48995, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877381

RESUMO

With the increasing prevalence of microbial infections, which results in prolonged inflammation and delayed wound healing, the development of effective and safe antimicrobial wound dressings of multiple properties remains challenging for public health. Despite their various formats, the available developed dressings with limited functions may not fulfill the diverse demands involved in the complex wound healing process. In this study, multifunctional sandwich-structured electrospinning nanofiber membranes (ENMs) were fabricated. According to the structural composition, the obtained ENMs included a hydrophilic inner layer loaded with curcumin and gentamicin sulfate, an antibacterial middle layer consisting of bovine serum albumin stabilized silver oxide nanoparticles, and a hydrophobic outer layer. The prepared sandwich-structured ENMs (SNM) exhibited good biocompatibility and killing efficacy on Escherichia coli, Staphylococcus aureus, and Methicillin-resistant S. aureus (MRSA). In particular, transcriptomic analysis revealed that SNM inactivated MRSA by inhibiting its carbohydrate and energy metabolism and reduced the bacterial resistance by downregulating mecA. In the animal experiment, SNM showed improved wound healing efficiency by reducing the bacterial load and inflammation. Moreover, 16S rDNA sequencing results indicated that SNM treatment may accelerate wound healing without observed influence on the normal skin flora. Therefore, the constructed sandwich-structured ENMs exhibited promising potential as dressings to deal with the infected wound management.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Nanofibras , Animais , Antibacterianos/química , Nanofibras/química , Resistência a Meticilina , Inflamação/tratamento farmacológico
13.
Micromachines (Basel) ; 13(7)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35888922

RESUMO

In this work, we obtained silver nanoparticles stabilized with polyvinylpyrrolidone, ranging in size from 70 to 110 nm, which exhibits good crystallinity and anisotropic structure. For the first time, we studied the influence of the molar ratio of silver between silver and peroxide on the oxidation process of the nanoparticles and determined the regularities of this process by analyzing changes in absorption spectra. Our results showed that at molar ratios of Ag:H2O2 = 1:1 and 1:5, dependences of changes in the intensity, position and half-width of the absorption band of the plasmon resonance are rectilinear. In vivo studies of silver nanoparticles have shown that silver nanoparticles belong to the toxicity class III (moderately hazardous substance) and to the third group according to the degree of accumulation. We established that silver nanoparticles and oxidized silver nanoparticles form a uniform layer on the surface of the suture material. We found that the use of the suture material with silver nanoparticles and oxidized silver nanoparticles does not cause allergic reactions in the organisms of laboratory animals.

14.
Food Chem Toxicol ; 165: 113170, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35613679

RESUMO

In this study, synthesis of silver nanoparticles (AgNPs) was carried out utilizing the red and green parts of the pistachio hulls then their several biological activities were investigated. The DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) activities of the AgNPs synthesized from red pistachio hulls extracts (PhR-AgNPs) and green pistachio hulls extracts (PhG-AgNPs) were investigated. The DPPH scavenging capability at 200 mg/L concentration of PhR-AgNPs was around 93.01% however PhG-AgNPs displayed 91.00%. The synthesized PhR-AgNPs and PhG-AgNPs acted on the E. coli plasmid DNA, causing its complete degradation and exhibiting effective chemical nuclease activity. Furthermore, PhR-AgNPs and PhG-AgNPs showed quite good antimicrobial activity against the studied strains with a range of the minimum inhibition concentration (MIC) of 8-16 mg/L. Moreover, it was observed that both pistachio hulls coated with AgNPs were highly effective in inhibiting the biofilm generation studied strains. Moreover, PhR-AgNP and PhG-AgNP displayed a completely inhibition effect on cellular viability of E. coli with 100% at 125 mg/L.


Assuntos
Nanopartículas Metálicas , Pistacia , Antibacterianos/farmacologia , Escherichia coli , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Prata/farmacologia
15.
Plants (Basel) ; 10(4)2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33916375

RESUMO

This study aimed to establish a rapid in vitro plant regeneration method from rhizome buds of Kaempferia parviflora to obtain the valuable secondary metabolites with antioxidant and enzyme inhibition properties. The disinfection effect of silver oxide nanoparticles (AgO NPs) on rhizome and effects of plant growth regulators on shoot multiplication and subsequent rooting were investigated. Surface sterilization of rhizome buds with sodium hypochlorite was insufficient to control contamination. However, immersing rhizome buds in 100 mg L-1 AgO NPs for 60 min eliminated contamination without affecting the survival of explants. The number of shoots (12.2) produced per rhizome bud was higher in Murashige and Skoog (MS) medium containing 8 µM of 6-Benzyladenine (6-BA) and 0.5 µM of Thidiazuron (TDZ) than other treatments. The highest number of roots (24), with a mean root length of 7.8 cm and the maximum shoot length (9.8 cm), were obtained on medium MS with 2 µM of Indole-3-butyric acid (IBA). A survival rate of 98% was attained when plantlets of K. parviflora were acclimatized in a growth room. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) was used to determine the chemical profile of K. parviflora leaf extracts. Results showed that several biologically active flavonoids reported in rhizomes were also present in leaf tissues of both in vitro cultured and ex vitro (greenhouse-grown) plantlets of K. parviflora. We found 40 and 36 compounds in in vitro cultured and ex vitro grown leaf samples, respectively. Greenhouse leaves exhibited more potent antioxidant activities than leaves from in vitro cultures. A higher acetylcholinesterase inhibitory ability was obtained for greenhouse leaves (1.07 mg/mL). However, leaves from in vitro cultures exhibited stronger butyrylcholinesterase inhibitory abilities. These results suggest that leaves of K. parviflora, as major byproducts of black ginger cultivation, could be used as valuable alternative sources for extracting bioactive compounds.

16.
Environ Sci Pollut Res Int ; 28(10): 12980-12992, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33097998

RESUMO

A novel potential adsorbent, produced with chitosan nanoparticles and silver/silver oxide nanoparticles impregnated on polyurethane foam (PFCA), is developed for phosphate removal in aqueous solutions. The ultraviolet-visible (UV-Vis) spectroscopy uncovered the emergence of nanoparticles. The field emission scanning electron microscopy (FESEM) provided the mean size of chitosan nanoparticles between 56 and 112 nm and that of silver-silver oxide nanoparticles between 44 and 75 nm. Energy dispersive X-ray (EDX) spectroscopy determined the presence of specific elements (C, O, P and Ag) in the adsorbent before and after treatment. Fourier transform infrared (FTIR) spectroscopy revealed the interplay between the N-H bond of amino group in PFCA and phosphate ions during adsorption. X-ray diffraction (XRD) analysis of PFCA showed nearly the same pattern before and after treatment, indicating the stability of PFCA. The silver ion concentration in the effluent from inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis was found to be very less and below the drinking water limits. The surface area estimated by Brunauer-Emmett-Teller (BET) studies was found to be 2.17 m2/g. The experimental studies showed that PFCA can remove 61.24% of phosphate from an influent phosphate phosphorus concentration of 50 mg P/L, at its propitious condition. Even after 7 cycles of reuse, PFCA proved to be effective in removing 20.58% of phosphate. Hence, PFCA can be considered to be a potential sorbent for removing phosphate from surface water. Graphical abstract.


Assuntos
Nanopartículas Metálicas , Fosfatos , Adsorção , Óxidos , Poliuretanos , Compostos de Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Membranes (Basel) ; 11(7)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202049

RESUMO

In this study, silver/silver oxide nanoparticles (Ag/Ag2O NPs) were successfully biosynthesized using Phoenix dactylifera L. aqueous leaves extract. The effect of different plant extract/precursor contractions (volume ratio, v/v%) on Ag/Ag2O NP formation, their optical properties, and photocatalytic activity towards azo dye degradation, i.e., Congo red (CR) and methylene blue (MB), were investigated. X-ray diffraction confirmed the crystalline nature of Ag/Ag2O NPs with a crystallite size range from 28 to 39 nm. Scanning electron microscope images showed that the Ag/Ag2O NPs have an oval and spherical shape. UV-vis spectroscopy showed that Ag/Ag2O NPs have a direct bandgap of 2.07-2.86 eV and an indirect bandgap of 1.60-1.76 eV. Fourier transform infrared analysis suggests that the synthesized Ag/Ag2O NPs might be stabilized through the interactions of -OH and C=O groups in the carbohydrates, flavonoids, tannins, and phenolic acids present in Phoenix dactylifera L. Interestingly, the prepared Ag/Ag2O NPs showed high catalytic degradation activity for CR dye. The photocatalytic degradation of the azo dye was monitored spectrophotometrically in a wavelength range of 250-900 nm, and a high decolorization efficiency (84.50%) was obtained after 50 min of reaction. As a result, the use of Phoenix dactylifera L. aqueous leaves extract offers a cost-effective and eco-friendly method.

18.
Materials (Basel) ; 14(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34832317

RESUMO

A method for obtaining a stable colloidal solution of silver oxide nanoparticles has been developed using laser ablation. The method allows one to obtain nanoparticles with a monomodal size distribution and a concentration of more than 108 nanoparticles per mL. On the basis of the obtained nanoparticles and the PLGA polymer, a nanocomposite material was manufactured. The manufacturing technology allows one to obtain a nanocomposite material without significant defects. Nanoparticles are not evenly distributed in the material and form domains in the composite. Reactive oxygen species (hydrogen peroxide and hydroxyl radical) are intensively generated on the surfaces of the nanocomposite. Additionally, on the surface of the composite material, an intensive formation of protein long-lived active forms is observed. The ELISA method was used to demonstrate the generation of 8-oxoguanine in DNA on the developed nanocomposite material. It was found that the multiplication of microorganisms on the developed nanocomposite material is significantly decreased. At the same time, the nanocomposite does not inhibit proliferation of mammalian cells. The developed nanocomposite material can be used as an affordable and non-toxic nanomaterial to create bacteriostatic coatings that are safe for humans.

19.
Ultrason Sonochem ; 50: 255-264, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30274888

RESUMO

The present work describes the sensing application and supercapacitive behavior of silver oxide nanoparticles recovered from wastewater of photo film processing units via one-pot green sonochemical recovery process. The recovered silver oxide nanoparticles (Ag2O NPs) were characterized by spectral techniques such as FT-IR, Raman, UV-Vis and analytical tools such as XRD, FE-SEM, TEM, EDX, XPS and BET. In view of Ag2O NPs as electrode material with wide technological applications, the recovered Ag2O NPs were examined for their sensing and supercapacitive behavior. The developed sensor was explored to detect 2, 4, 6-trichlorophenol, and as expected it shows moral parameters which are required of an effective sensor. Therefore, it was exploited for the quantification of 2, 4, 6-trichlorophenol in soil samples from the agricultural area. Cyclic voltammetric (CV), Galvanostatic Charge-Discharge (GCD) and Electrochemical Impedance Spectroscopic (EIS) studies on the recovered Ag2O NPs coated Ni foam electrode depicted the pronounced capacitive behavior. The GCD studies revealed an enhanced electrochemical performance, particularly with the large specific capacitance of 530 F/g at a current density of 1 A/g. The cyclic stability of the electrode material was identified with 88% retention in specific capacitance even after 5000 GCD cycles. These results strongly proved that the recovered Ag2O NPs are potential candidates for sensing and supercapacitor applications.

20.
J Colloid Interface Sci ; 513: 62-71, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29132106

RESUMO

The synergistic wound healing and antibacterial activity of silver oxide nanoparticles embedded silk fibroin (Ag2O-SF) spuns is reported here. UV-Vis spectro photometric analysis of these spuns showed the surface plasmon resonance (SPR) confirming the formation of the silver oxide nanoparticles (Ag2O NPs) on the surface of the silk fibroin (SF). Scanning electron microscope (SEM) and Differential scanning calorimetry (DSC) also confirmed the presence of Ag2O NPs on surface of SF. X-ray diffraction (XRD) analysis revealed the crystalline nature of both SF and Ag2O-SF. Fourier transform infrared spectroscopy (FT-IR) results showed the different forms of silk (I and II) and their corresponding protein (amide I, II, III) confirmations. Biodegradation study revealed insignificant changes in the morphology of Ag2O-SF spuns even after 14 days of immersion in phosphate buffered saline (PBS). Ag2O-SF spuns showed excellent antibacterial activity against both pathogen (S. aureus and M. tuberculosis) and non-pathogen (E. coli) bacteria. More importantly, In vitro wound healing (scratch assay) assay revealed fast migration of the T3T fibroblast cells through the scratch area treated with extract of Ag2O-SF spuns and the area was completely covered within 24 h. Cytotoxicity assay confirmed the biocompatible nature of the Ag2O-SF spuns, thus suggesting an ideal material for wound healing and anti-bacterial applications.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Fibroínas/química , Nanopartículas Metálicas/química , Micro-Ondas , Óxidos/farmacologia , Compostos de Prata/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Proliferação de Células/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Óxidos/química , Compostos de Prata/química
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