Green synthesis Dotaz Zobrazit nápovědu
Zinc oxide/cellulose nanocrystal (ZnO/CNC) hybrids with modulated morphologies were prepared by using bamboo CNC as templates via green one-step technique. The effect of pH values on the morphology, microstructure, thermal stability, antibacterial efficiency and dye absorption kinetics of hybrids were investigated. A possible mechanism for various hybrid morphologies at different pH values was provided. All the samples exhibited high antibacterial ratios of 91.4%-99.8% against both Escherichia coli and Staphylococcus aureus. ZnO/CNC8.5 gave quick removal efficiency with high dye removal ratios in methylene blue (MB, 93.55%) and malachite green (MG, 99.02%), especially >91.47% and 97.85% within 5 min. The absorption capacity could reach up to 46.77 mg/g for MB and 49.51 mg/g for MG. Besides, absorption kinetics showed that the absorption behavior followed the pseudo-second-order kinetic model (R2 > 0.99996). Such ZnO/CNC hybrids show outstanding and low-cost adsorbent for efficient absorption of cationic dyes in wastewater treatment field.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- barvicí látky chemie izolace a purifikace MeSH
- celulosa chemie MeSH
- čištění vody MeSH
- Escherichia coli účinky léků MeSH
- fyzikální absorpce * MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- methylenová modř chemie izolace a purifikace MeSH
- nanočástice chemie MeSH
- odpadní voda chemie MeSH
- oxid zinečnatý chemie farmakologie MeSH
- rosanilinová barviva chemie izolace a purifikace MeSH
- Staphylococcus aureus účinky léků MeSH
- techniky syntetické chemie MeSH
- technologie zelené chemie MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
The growth rate hypothesis (GRH) predicts a positive correlation between growth rate and RNA content because growth depends upon the protein synthesis machinery. The application of this hypothesis to photoautotrophic organisms has been questioned. We tested the GRH on one prasinophycean, Tetraselmis suecica, and one chlorophycean, Dunaliella salina, grown at three sulphate concentrations. Sulphate was chosen because its concentration in the oceans increased through geological time and apparently had a role in the evolutionary trajectories of phytoplankton. Cell protein content and P quota were positively related to the RNA content (r = 0.62 and r = 0.74, respectively). The correlation of the RNA content with growth rates (r = 0.95) indicates that the GRH was valid for these species when growth rates were below 0.82 d(-1) .
- MeSH
- Chlorophyta růst a vývoj metabolismus MeSH
- dusík metabolismus MeSH
- mořská voda chemie MeSH
- oceány a moře MeSH
- proteosyntéza * MeSH
- ribozomy metabolismus MeSH
- RNA metabolismus MeSH
- sírany metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- oceány a moře MeSH
In this study, selective green synthesis of gold nanoparticles (nAu) with the use of Tarragon extract (Artemisia dracunculus) was investigated. Characterization of the synthetized nAu was carried out using several techniques including: UV-Vis, SEM, zeta potential analysis, DLS, and ATR-FTIR. Based on measurements of Tarragon extract by HPLC-MS, significant chemical substances participating as reducing and stabilizing agents were identified. FTIR confirmed typical functional groups that could be found in these acids on the nAu surface, such as O-H, C=O and C-O. The effects of various parameters (concentration of Tarragon extract, Au precursor, and initial pH of the synthesis) on the shape and size of the nanoparticles have been investigated. UV-Vis and SEM confirmed the formation of nAu at various concentrations of the extract and Au precursor and showed correlation between the added extract concentration and shift in maximal absorbance towards higher frequencies, indicating the formation of smaller nanoplates. Zeta potential determined at various pH levels revealed that its value decreased with pH, but for all experiments in the pH range of 2.8 to 5.0, the value is below - 30 mV, an absolute value high enough for long-term nAu stability. In order to evaluate nAu catalytic activity, the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride was used as a model system. The reaction takes place 1.5 times faster on Au-triangles than on Au-spherical NPs.
- MeSH
- aminofenoly chemie MeSH
- borohydridy chemie MeSH
- katalýza MeSH
- koncentrace vodíkových iontů MeSH
- kovové nanočástice chemie MeSH
- mikroskopie elektronová rastrovací MeSH
- nitrofenoly chemie MeSH
- pelyněk chemie MeSH
- rostlinné extrakty analýza chemie MeSH
- spektrofotometrie ultrafialová MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- tandemová hmotnostní spektrometrie MeSH
- technologie zelené chemie metody MeSH
- velikost částic MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- zlato chemie MeSH
- Publikační typ
- časopisecké články MeSH
Cobalt oxide nanoparticles were prepared via green chemistry route and fully characterized by Field Emission Scanning Electron Microscope (FESEM), Energy-dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), High-resolution transmission electron microscopy (HRTEM) and Transmission electron microscopy (TEM) analyses; the CoO and Co3O4 nanoparticles, in sheet-shaped cobalt oxide form, ensued simultaneously in one step. The varying concentrations of NPs were analyzed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test on the cancer cell line (U87) which revealed that with increasing concentration of cobalt oxide nanoparticles, the survival rate of U87 tumor cells decreases; IC50 of nanoparticles being ~ 55 µg/ml-1.
- MeSH
- antibakteriální látky chemie MeSH
- difrakce rentgenového záření MeSH
- inhibiční koncentrace 50 MeSH
- kobalt chemie MeSH
- koncentrace vodíkových iontů MeSH
- kovové nanočástice chemie MeSH
- lidé MeSH
- magnetismus MeSH
- mikrobiální testy citlivosti MeSH
- nádorové buněčné linie MeSH
- nanomedicína metody MeSH
- nanotechnologie metody MeSH
- oxidy chemie MeSH
- povrchově aktivní látky MeSH
- protinádorové látky farmakologie MeSH
- rostlinné extrakty MeSH
- rozmarýn MeSH
- rozpustnost MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- technologie zelené chemie metody MeSH
- teplota MeSH
- tetrazoliové soli chemie MeSH
- thiazoly chemie MeSH
- transmisní elektronová mikroskopie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
In this study, a simple and green strategy was reported to prepare bimetallic nanoparticles (NPs) by the combination of zinc oxide (ZnO) and copper oxide (CuO) using Sambucus nigra L. extract. The physicochemical properties of these NPs such as crystal structure, size, and morphology were studied by X-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM), and transmission electron microscopy (TEM). The results suggested that these NPs contained polygonal ZnO NPs with hexagonal phase and spherical CuO NPs with monoclinic phase. The anticancer activity of the prepared bimetallic NPs was evaluated against lung and human melanoma cell lines based on MTT assay. As a result, the bimetallic ZnO/CuO NPs exhibited high toxicity on melanoma cancer cells while their toxicity on lung cancer cells was low.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- bez černý chemie MeSH
- buňky A549 MeSH
- cytotoxiny chemie farmakologie MeSH
- difrakce rentgenového záření metody MeSH
- kovové nanočástice chemie MeSH
- lidé MeSH
- listy rostlin chemie MeSH
- měď chemie farmakologie MeSH
- mikrobiální testy citlivosti metody MeSH
- nádorové buněčné linie MeSH
- oxid zinečnatý chemie farmakologie MeSH
- rostlinné extrakty chemie farmakologie MeSH
- spektroskopie infračervená s Fourierovou transformací metody MeSH
- technologie zelené chemie metody MeSH
- transmisní elektronová mikroskopie metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Fruit extracts have natural bioactive molecules that are known to possess significant therapeutic potential. Traditionally, metallic nanoparticles were synthesized via chemical methods, in which the chemical act as the reducing agent. Later, these traditional metallic nanoparticles emerged as the biological risk, which prompted researchers to explore an eco-friendly approach. There are different eco-friendly methods employed for synthesizing these metallic nanoparticles via the usage of microbes and plants, primarily via fruit extract. These explorations have paved the way for using fruit extracts for developing nanoparticles, as they eliminate the usage of reducing and stabilizing agents. Metallic nanoparticles have gained significant attention, and are used for diverse biological applications. The present review discusses the potential activities of phytochemicals, and it intends to summarize the different metallic nanoparticles synthesized using fruit extracts and their associated pharmacological activities like anti-cancerous, antimicrobial, antioxidant and catalytic efficiency.
Metal nanoparticles belong to the most fabricated nanomaterials because of their unique physical and chemical properties which can be used for analytical, biochemical and biotechnological applications. Biosynthesis of metal nanoparticles has been extensively studied since the present production of nanoparticles by chemical and physical methods is difficult in terms of the use of toxic chemicals and energy consumption. In plants, there is the largest accumulation of heavy metals in the ecosystem. Therefore plants have a great potential for the biosynthesis of nanoparticles. Influence of various external reaction´s conditions can affect appearance of produced nanoparticles. This fact opens unlimited possibilities for biosynthesis of novel nanoparticles that may vary in size, shape and surface modification.
- Klíčová slova
- biologická syntéza, nanobiotechnologie, biosyntéza,
- MeSH
- fotosyntéza * MeSH
- kovové nanočástice * chemie MeSH
- rostlinné extrakty * MeSH
- stříbro chemie MeSH
- teplota MeSH
- zlato chemie MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
BACKGROUND: Copper oxide (CuO) nanoparticles have attracted huge attention due to catalytic, electric, optical, photonic, textile, nanofluid, and antibacterial activity depending on the size, shape, and neighboring medium. In the present paper, we synthesized CuO nanoparticles using gum karaya, a natural nontoxic hydrocolloid, by green technology and explored its potential antibacterial application. METHODS: The CuO nanoparticles were synthesized by a colloid-thermal synthesis process. The mixture contained various concentrations of CuCl2 • 2H2O (1 mM, 2 mM, and 3 mM) and gum karaya (10 mg/mL) and was kept at 75°C at 250 rpm for 1 hour in an orbital shaker. The synthesized CuO was purified and dried to obtain different sizes of the CuO nanoparticles. The well diffusion method was used to study the antibacterial activity of the synthesized CuO nanoparticles. The zone of inhibition, minimum inhibitory concentration, and minimum bactericidal concentration were determined by the broth microdilution method recommended by the Clinical and Laboratory Standards Institute. RESULTS: Scanning electron microscopy analysis showed CuO nanoparticles evenly distributed on the surface of the gum matrix. X-ray diffraction of the synthesized nanoparticles indicates the formation of single-phase CuO with a monoclinic structure. The Fourier transform infrared spectroscopy peak at 525 cm(-1) should be a stretching of CuO, which matches up to the B2u mode. The peaks at 525 cm(-1) and 580 cm(-1) indicated the formation of CuO nanostructure. Transmission electron microscope analyses revealed CuO nanoparticles of 4.8 ± 1.6 nm, 5.5 ± 2.5 nm, and 7.8 ± 2.3 nm sizes were synthesized with various concentrations of CuCl2 • 2H2O (1 mM, 2 mM, and 3 mM). X-ray photoelectron spectroscopy profiles indicated that the O 1s and Cu 2p peak corresponding to the CuO nanoparticles were observed. The antibacterial activity of the synthesized nanoparticles was tested against Gram-negative and positive cultures. CONCLUSION: The formed CuO nanoparticles are small in size (4.8 ± 1.6 nm), highly stable, and have significant antibacterial action on both the Gram classes of bacteria compared to larger sizes of synthesized CuO (7.8 ± 2.3 nm) nanoparticles. The smaller size of the CuO nanoparticles (4.8 ± 1.6 nm) was found to be yielding a maximum zone of inhibition compared to the larger size of synthesized CuO nanoparticles (7.8 ± 2.3 nm). The results also indicate that increase in precursor concentration enhances an increase in particle size, as well as the morphology of synthesized CuO nanoparticles.
- MeSH
- antibakteriální látky chemická syntéza chemie farmakologie MeSH
- difrakce rentgenového záření MeSH
- Escherichia coli účinky léků MeSH
- guma karaya chemie MeSH
- kovové nanočástice chemie MeSH
- měď chemie farmakologie MeSH
- mikrobiální testy citlivosti MeSH
- nanotechnologie metody MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- Staphylococcus aureus účinky léků MeSH
- technologie zelené chemie metody MeSH
- transmisní elektronová mikroskopie MeSH
- velikost částic MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Nanoparticles have drawn significant interest in a range of applications, ranging from biomedical to environmental sciences, due to their distinctive physicochemical characteristics. In this study, it was reported that simple biological production of Ag, Se, and bimetallic Ag2Se nanoparticles (NPs) with Pseudomonas aeruginosa is a promising, low-cost, and environmentally friendly method. For the first time in the scientific literature, Ag2Se nanoparticles have been generated via green bacterial biosynthesis. UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and EDX were used to characterize the produced NPs. Biosynthesized NPs were examined for antibacterial, antibiofilm, and photocatalytic properties, and it was determined that the effects of NPs were dose dependent. The biosynthesized AgNPs, SeNPs, and Ag2Se NPs showed anti-microbial activity against Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentrations (MICs) of E. coli and S. aureus were between 150 and 250 μg/mL. The NPs showed antibiofilm activity against E. coli and S. aureus at sub-MIC levels and reduced biofilm formation by at least 80% at a concentration of 200 μg/mL of each NPs. To photocatalyze the breakdown of Congo red, Ag, Se, and Ag2Se NPs were utilized, and their photocatalytic activity was tested at various concentrations and intervals. A minor decrease of photocatalytic degradation was detected throughout the NPs reuse operation (five cycles). Based on the encouraging findings, the synthesized NPs demonstrated antibacterial, antibiofilm, and photocatalytic properties, suggesting that they might be used in pharmaceutical, medical, environmental, and other applications.
- MeSH
- antibakteriální látky * farmakologie chemie chemická syntéza MeSH
- biofilmy * účinky léků MeSH
- Escherichia coli * účinky léků MeSH
- katalýza MeSH
- kovové nanočástice * chemie MeSH
- mikrobiální testy citlivosti * MeSH
- Pseudomonas aeruginosa * účinky léků metabolismus MeSH
- selen chemie farmakologie MeSH
- sloučeniny stříbra chemie farmakologie MeSH
- Staphylococcus aureus * účinky léků MeSH
- stříbro * chemie farmakologie metabolismus MeSH
- technologie zelené chemie * MeSH
- Publikační typ
- časopisecké články MeSH
