Green nanoparticle synthesis is an environmentally friendly approach that uses natural solvents. It is preferred over chemical and physical techniques due to the time and energy savings. This study ...aimed to synthesize zinc oxide nanoparticles (ZnO NPs) through a green method that used Phlomis leaf extract as an effective reducing agent. The synthesis and characterization of ZnO NPs were confirmed by UV-Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic light scattering (DLS), Zeta potential, and Field Emission Scanning Electron Microscope (FESEM) techniques. In vitro cytotoxicity was determined in L929 normal fibroblast cells using MTT assay. The antibacterial activity of ZnO nanoparticles was investigated using a disk-diffusion method against S. aureus and E. coli, as well as minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) content concentrations. XRD results confirmed the nanoparticles’ crystalline structure. Nanoparticle sizes were found to be around 79 nm by FESEM, whereas the hydrodynamic radius of nanoparticles was estimated to be around 165 ± 3 nm by DLS. FTIR spectra revealed the formation of ZnO bonding and surfactant molecule adsorption on the surface of ZnO NPs. It is interesting to observe that aqueous extracts of Phlomis leave plant are efficient reducing agents for green synthesis of ZnO NPs in vitro, with no cytotoxic effect on L929 normal cells and a significant impact on the bacteria tested.
Flaky graphene oxide (GO) nanoparticles (NPs) were synthesized using Hummer’s method and then capped with polyethylene glycol (PEG) by an esterification reaction, then loaded with Nigella sativa (N. ...sativa) seed extract. Aiming to investigate their potential use as a smart drug delivery system against Staphylococcus aureus and Escherichia coli, the spectral and structural characteristics of GO-PEG NPs were comprehensively analyzed by XRD, AFM, TEM, FTIR, and UV- Vis. XRD patterns revealed that GO-PEG had different crystalline structures and defects, as well as a higher interlayer spacing. AFM results showed GONPs with the main grain size of 24.41 nm, while GONPs–PEG revealed graphene oxide aggregation with the main grain size of 287.04 nm after loading N. sativa seed extract, which was verified by TEM examination. A strong OH bond appeared in FTIR spectra. Furthermore, UV- Vis absorbance peaks at (275, 284, 324, and 327) nm seemed to be correlated with GONPs, GO–PEG, N. sativa seed extract, and GO –PEG- N. sativa extract. The drug delivery system was observed to destroy the bacteria by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell wall integrity, nucleic acid damage, and increased cell-wall permeability.
Abstract
This study investigated for the first time a simple bio-synthesis approach for the synthesis of copper oxide nanoparticles (CuO NPs) using
Annona muricata L
(
A. muricata
) plant extract to ...test their anti-cancer effects. The presence of CuONPs was confirmed by UV–visible spectroscopy, Scanning electron microscope (SEM), and Transmission electron microscope (TEM). The antiproliferative properties of the synthesized nanoparticles were evaluated against (AMJ-13), (MCF-7) breast cancer cell lines, and the human breast epithelial cell line (HBL-100) as healthy cells. This study indicates that CuONPs reduced cell proliferation for AMJ-13 and MCF-7. HBL-100 cells were not significantly inhibited for several concentration levels or test periods. The outcomes suggest that the prepared copper oxide nanoparticles acted against the growth of specific cell lines observed in breast cancer. It was observed that cancer cells had minor colony creation after 24 h sustained CuONPs exposure using (IC
50
) concentration for AMJ-13 was (17.04 µg mL
−1
). While for MCF-7 cells was (18.92 µg mL
−1
). It indicates the uptake of CuONPs by cancer cells, triggering apoptosis. Moreover, treatment with CuONPs enhanced Lactate dehydrogenase (LDH) production, probably caused by cell membrane damage, creating leaks comprising cellular substances like lactate dehydrogenase. Hence, research results suggested that the synthesized CuONPs precipitated anti-proliferative effects by triggering cell death through apoptosis.
Compared to traditional physical and chemical approaches, nanobiotechnology and plant-based green synthesis procedures offer significant advantages, as well as having a greater range of medical and ...biotechnological applications. Nanoparticles of zinc oxide (ZnO NPs) have recently been recognized as a promising option for many industries, including optics, electrics, packaged foods, and medicine, due to their biocompatibility, low cytotoxicity, and cost-effectiveness. Several studies have shown that zinc ions are important in triggering cell apoptosis by promoting the generation of reactive oxygen species (ROSs) and releasing zinc ions (Zn2+), which are toxic to cells. The toxic nature of the chemicals used in the synthesis of ZnO nanoparticles limits their clinical utility. An overview of recent developments in green ZnO NP synthesis is presented in this review, emphasizing plant parts as reducing agents and their medical applications, including their antimicrobial, anticancer, antioxidant, and anti-inflammatory properties, as well as key mechanisms of action for these applications to facilitate further research on the biomedical fields in the future.
Green synthesis of nanoparticles (NPs) is a more sustainable, safe, and environmentally friendly method. This study aimed to investigate the synthesis procedure of iron oxide nanoparticles (IONPs) ...using the seed extract of
(
) as a strong reducing agent and to estimate their cytotoxic and antibacterial properties. The obtained IONPs were characterized by field-emission scanning electron microscopy, X-ray diffraction, dynamic light scattering (DLS), zeta potential (ZP), and Fourier-transform infrared spectroscopy analyses. The cytotoxicity of the biosynthesized IONPs was demonstrated by the MTT on a Vero cell line. Furthermore, the antibacterial activity of the fabricated biosynthesis metal oxide NPs was tested on
(
) (ATCC 35218) and
(
) (ATCC 29213) bacterial strains using the Kirby–Bauer disk diffusion method. This study showed the formation of a well-dispersed, highly stable (ZP
= −51.8 mV) IO NPs with an average diameter of about 31.45 nm. Moreover, the biosynthetic NPs (IONPs) exhibited a significantly noncytotoxic effect when analyzed by the MTT assay. The biosynthetic NPs (NS-IONPs) exhibited excellent antibacterial activity against
and
, where the inhibition zones were 12.34 ± 0.58 and 11.52 ± 0.58, respectively.
Recently, natural substances in the form of nanoparticles are increasingly being used in different field, particularly in medicines to enhance their beneficial effects in treatment and prevention. ...Cancer cells of the breast (MCF-7) have been chosen to be examined and treated in vitro
with conventional drug Tamoxifen (Tam) and tannin nanoparticles extract (NP99) individually or in combination. MTT reagent has been applied to assess the cell viability and propagation percentage, DNA fragmentation and mRNA relative expression of apoptotic genes to study the cell death pathway.
The results showed that Tam and tannin NP99 triggered cytotoxic activity towards the MCF7 cell. They reduce the viability and induced high potent repressive activity on cell proliferation percentage and induced apoptosis as indicated by rising the percentage in DNA fragmentation. Effect of
NP99 extract exhibited its effect in a dose and time-varying. The combined treatment of Tam and NP99 were much more efficient than individual drugs. It could be concluded that NP99 is considered a promising natural anticancer agent as a new tool in therapeutic strategies.
Carbon nanomaterials are ground-breaking two-dimensional materials with a wide range of applications because of their unique properties, which include excellent optical, electrical, thermal, and ...mechanical capabilities; biocompatibility; and inexpensive large-scale production costs. In this study, carbon nanostructural materials (CNMs) were effectively generated using a pulsed laser ablation method on a graphite target immersed in deionized water, and their cytotoxicity and antibacterial activities were evaluated. Lasing pulse duration, ns (1064 nm) with different laser energies (60-220 mJ), was employed for irradiating the target. The formation of CNMs was analyzed using Fourier transform infrared spectroscopy, which demonstrated that C–H, C–C, C–O, and C=C bonds were successfully formed. TEM micrographs observed CNM formation with a spherical shape and size ranging from 20 to 90 nm. The absorbance was measured using UV-Vis spectroscopy; it increased with increasing laser energy showing two broad shoulders around 210 and 305 nm. Thereafter, the antibacterial activity was tested against Escherichia coli and Staphylococcus aureus using the agar method. The results indicated that CNMs fabricated at laser energy 220 mJ have the highest activity against both strains and have presented inhibition zone (IZ) of about 34±1.0 mm in S. aureus and 31±1.5 mm for E. coli. A comparison with CNMs prepared at 160 mJ showed an IZ of 14 mm for S. aureus and of 12 mm for E. coli due to synergistic impact, while the cellular material release analysis displayed increased release with respect to the time of exposure due to inhibition of bacterial growth.
Maintenance of genome integrity requires that branched nucleic acid molecules be accurately processed to produce double-helical DNA. Flap endonucleases are essential enzymes that trim such branched ...molecules generated by Okazaki-fragment synthesis during replication. Here, we report crystal structures of bacteriophage T5 flap endonuclease in complexes with intact DNA substrates and products, at resolutions of 1.9-2.2 Å. They reveal single-stranded DNA threading through a hole in the enzyme, which is enclosed by an inverted V-shaped helical arch straddling the active site. Residues lining the hole induce an unusual barb-like conformation in the DNA substrate, thereby juxtaposing the scissile phosphate and essential catalytic metal ions. A series of complexes and biochemical analyses show how the substrate's single-stranded branch approaches, threads through and finally emerges on the far side of the enzyme. Our studies suggest that substrate recognition involves an unusual 'fly-casting, thread, bend and barb' mechanism.
Nanoparticles of gold with zinc oxide (Au@ZnO NPs) were prepared by laser ablation and then capped with curcumin nanoparticles (Cur-Au@ZnO NPs). The synthesized NPs were characterized using different ...techniques, including transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), UV-visible spectroscopy, and X-ray diffraction. In addition, the ability of NPs as a promising antibacterial agent was tested against Staphylococcus aureus through the agar well diffusion method and AO/EtBr staining assay. The results showed that the prepared nanoparticles (Cur-Au@ZnO) served as an antibacterial agent and can destroy the bacterial cells by losing the cell wall integrity and penetrating the cytoplasmic membrane. Moreover, the findings confirmed the role of the formed NPs in attenuation of the adherence and invasion of S. aureus to rat embryonic fibroblast (REF) cells. Furthermore, the activity of Cur-Au@ZnO NPs against the S. aureus α-hemolysin toxin was evaluated using the western blot technique, using human alveolar epithelial cells (A549), and through histopathology examination in a mouse model. In conclusion, the built Cur-Au@ZnO NPs can be used as a potential antibacterial agent and an inhibitor of α-hemolysin toxin secreted by S. aureus. These NPs may offer a new strategy in combating pathogen infections and in the future for biomedical and pharmaceutical applications.
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