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1.
Nanomaterials (Basel) ; 12(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432239

RESUMO

In this study, ZnO nanoparticles were prepared by a hydrothermal method with varying the reaction times, material ratios and reaction temperatures. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray Diffraction (XRD) and Fourier infrared spectroscopy (FTIR). It was shown that the material ratio significantly affected the structure and morphology of the synthesized ZnO nanoparticles, and then the uneven nano-octahedral structure, uniform nano-octahedral structure, nano-tubular structure, and nano-sheet structure could be obtained successively. The synthesized ZnO nanoparticles as mordant were used for the dyeing of silk fabrics with different natural dyes (tea polyphenols and hematoxylin). Moreover, they could improve the dyeing properties and fastness (wash and light) on silk fabrics to a certain extent.

2.
Arch Razi Inst ; 77(1): 101-110, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35891745

RESUMO

Molds have been used as micro-biofactories for biomanufacturing of metal oxide nanoparticles (MetNps) since they are effortless, immaculate, safe, non-poisonous, vital-biocompatible, and environmentally acceptable. The present study aimed to explore the bioindustry, mold screening protocol, and characterization of zinc oxide nanoparticles (ZnONPs) using a diverse filamentous Green mold (FiGM) isolated from spoiled citrus fruits. Eight filamentous Penicillium Digitatum mold strains had been obtained and subjected to investigate the capability of ZnONPs biosynthesis by fungal extracellular free-cell filtrate. P. digitatum (P-digB3) obtained the peak of ZnONps (379 nm) detected by the UV-visible spectrophotometry and was found as a significantly optimum strain in the highest quantity (mean±SD: 0.0138±0.001 gm/100 ml) and the smallest average NPs size. The ZnONPs were characterized by UV-visible scanning spectrophotometry, Atomic Force Microscopy, X-RD, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The final average size of ZnONPs was obtained at 65.46 nm with diversified shapes and dimensions. The present study concluded the high capabilities of fungi (FiGMs) as eco-friendly and cheap bio-nano factories to manufacture ZnONPs with great nano-level average size, which may consider new boost sources for use in many nano-sectors and applications.


Assuntos
Nanopartículas Metálicas , Penicillium , Óxido de Zinco , Animais , Extratos Vegetais , Óxido de Zinco/farmacologia
3.
Micron ; 158: 103288, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35468500

RESUMO

The insufficient pollinator visitation is the most important limitation of fruit and seed production, which is common and ubiquitous in entomophilous angiosperms. The scent and attractive colours with flower guides and such floral rewards as nectar, pollen, and oil are important attractants for insects visiting and pollinating flowers in the family Iridaceae. The aim of this study was to investigate the morphology of flowers and the micromorphology, anatomy, and ultrastructure of floral nectaries in the rare and endangered species Iris sibirica with the use of light, scanning, and transmission electron microscopes and histochemical assays. Osmophores in the form of papillae were located on the adaxial surface of outer tepals and on the abaxial surface of the stylodium channel. The nectaries were located on the inner surface of the perianth tube and were composed of a single-layered epidermis with papillae and several layers of glandular parenchyma with vascular bundles. I. sibirica nectaries represent the presecretory starch-accumulating type, where nectar is released for a short time immediately after flower opening. Nectar was produced throughout the flower lifespan in both male and female stages. It was secreted in the granulocrine mode and released through microchannels in the reticulate cuticle of nectary papillae. Transport of pre-nectar components proceeded via symplastic and apoplastic pathways. The nectary epidermal cells with papillae and glandular parenchyma cells contained total lipids, acidic lipids, and polysaccharides, whereas the epidermal cells with papillae additionally contained neutral lipids and polyphenol compounds. The nectaries and nectar production in I. sibirica flowers share the common location and follow several secretion patterns characteristic for the nectaries in some members of the family Iridaceae and the subfamily Iridoideae. Nevertheless, the mode of nectar release through the cuticle of epidermal papillae has been described in Iridaceae family for the first time. The visual, aromatic, and food attractants characteristic of I. sibirica flowers probably stimulate potential visits by pollinators, but the short nectar secretion period may limit the effectiveness of pollinators and sexual reproductive success.


Assuntos
Gênero Iris , Néctar de Plantas , Flores/química , Gênero Iris/metabolismo , Lipídeos/análise , Néctar de Plantas/análise , Néctar de Plantas/química , Néctar de Plantas/metabolismo
4.
Data Brief ; 22: 336-343, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30596129

RESUMO

Coconut kernel shell (CKS) and palm kernel shell (PKS) powders were analyzed using Surface Electron Microcopy (SEM) and Transmission Electron Microscopy (TEM). The SEM and TEM were combined with Energy Dispersive X-ray Spectroscopy Analysis for elemental composition of the sample materials. The micrographs of all samples were thoroughly examined and explained. The dataset presented herein helps to elucidate the ultrastructure and could suggest expanding traditional applications of the PKS/CKS to novel ones. The data are related to the research article "Insight on the Ultrastructure, Physicochemical and Thermal Characteristics and Applications of the Palm Kernel Shells" (Ntenga et al., 2018).

5.
Chem Biol Drug Des ; 90(5): 943-952, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28498641

RESUMO

Twenty-one novel 5-phenyl-1,3,4-oxadiazole-2-thiol (POT) substituted N-hydroxyethyl quaternary ammonium salts (6a-g, 7a-g, 8a-g) were prepared and characterized by FTIR, NMR, and elemental analysis. Compounds 6a, 6c, and 8a were confirmed by X-ray single-crystal diffraction. They display the unsurpassed antibacterial activity against Staphylococcus aureus, α-H-tococcus, Escherichia coli, P. aeruginosa, Proteus vulgaris, Canidia Albicans, especially 6g, 7g, 8g with dodecyl group. Compounds 8a-d with N,N-dihydroxyethyl and POT groups display unsurpassed antibacterial activity and non-toxicity. The structure-activity relationships indicate that POT and flexible dihydroxyethyl group in QAS are necessary for antibacterial activity and cytotoxicity. SEM and TEM images of E. coli morphologies of 8d show the antibacterial agents can adhere to membrane surfaces to inhibit bacterial growth by disrupting peptidoglycan formation and releasing bacterial cytoplasm from cell membranes.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Oxidiazóis/farmacologia , Compostos de Amônio Quaternário/farmacologia , Antibacterianos/química , Infecções Bacterianas/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Oxidiazóis/química , Proteus vulgaris/efeitos dos fármacos , Compostos de Amônio Quaternário/química , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
6.
Adv Biosyst ; 1(12): e1700113, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32646158

RESUMO

One infection mechanism of plant viruses is the generation of nanotubes by viral movement proteins, allowing cell-to-cell virus particle transport. Previously, it was assumed that viral nanotubes extend directly from the host-cell plasma membrane. In virus-infected plants, these nanotubes reach an extraordinary diameter:length ratio (≈100 nm:µm or mm range). Here, viral nanotubes are produced in a transient protoplast system; the coding sequence for alfalfa mosaic virus movement protein is translationally fused to green fluorescent protein. The maximum extension of viral nanotubes into the culture medium is achieved 24-48 h posttransfection, with lengths in the micro- and millimeter ranges. Scanning electron microscopy and transmission electron microscopy show that strong inhomogeneous viral nanotubes are formed compared to particle-filled systems. The nanotubes have similar length, but fluctuating wall thickness and diameter and are susceptible to entanglement and recombination. Indirect methods demonstrate that movement proteins assemble independently at the top of the nanotube. These viral nanotubes grow distinctly from previously known natural particle-filled systems and are a unique biological tubular nanomaterial that has the potential for micro- or nanoapplications as a mechanically stable structural component.

7.
J Biomol Struct Dyn ; 34(8): 1778-96, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26360629

RESUMO

Recent crystallographic study revealed the involvement of allosteric site in active site inhibition of penicillin binding protein (PBP2a), where one molecule of Ceftaroline (Cef) binds to the allosteric site of PBP2a and paved way for the other molecule (Cef) to bind at the active site. Though Cef has the potency to inhibit the PBP2a, its adverse side effects are of major concern. Previous studies have reported the antibacterial property of Quercetin derivatives, a group of natural compounds. Hence, the present study aims to evaluate the effect of Quercetin 3-o-rutinoside (Rut) in allosteric site-mediated active site inhibition of PBP2a. The molecular docking studies between allosteric site and ligands (Rut, Que, and Cef) revealed a better binding efficiency (G-score) of Rut (-7.790318) and Cef (-6.194946) with respect to Que (-5.079284). Molecular dynamic (MD) simulation studies showed significant changes at the active site in the presence of ligands (Rut and Cef) at allosteric site. Four different combinations of Rut and Cef were docked and their G-scores ranged between -6.320 and -8.623. MD studies revealed the stability of the key residue (Ser403) with Rut being at both sites, compared to other complexes. Morphological analysis through electron microscopy confirmed that combination of Rut and Cefixime was able to disturb the bacterial cell membrane in a similar fashion to that of Rut and Cefixime alone. The results of this study indicate that the affinity of Rut at both sites were equally good, with further validations Rut could be considered as an alternative for inhibiting MRSA growth.


Assuntos
Regulação Alostérica , Sítio Alostérico , Domínio Catalítico , Glucosídeos/química , Modelos Moleculares , Proteínas de Ligação às Penicilinas/química , Quercetina/análogos & derivados , Antibacterianos/química , Antibacterianos/farmacologia , Sítios de Ligação , Glucosídeos/farmacologia , Ligação de Hidrogênio , Ligantes , Testes de Sensibilidade Microbiana , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteínas de Ligação às Penicilinas/antagonistas & inibidores , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Quercetina/química , Quercetina/farmacologia
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