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1.
Chem Biodivers ; 20(8): e202300743, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37438322

RESUMO

In the context of the proposed work, two different amino acids (Glycine, Phenylalanine) have interacted with copper ions in a phosphate buffer (PBS) in place of enzymes. This interaction resulted in the nucleation of copper phosphate crystals and the formation of flower-shaped amino acid-copper hybrid nanostructures (AA-hNFs), which grew through self-assembly. While Cu (II) ions in the structure of AA-hNFs were used as Fenton's agent for the catalytic activity. SEM, energy dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy measurements were used to define the AA-hNFs' characterisation. The peroxidase-like activities of AA-hNFs were investigated by UV/VIS spectrophotometer. Metal nanoparticles have peroxidase-like activity. A class of enzymes known as peroxidases is able to catalyze the conversion of hydrogen peroxide into hydroxyl radicals. These radicals also take part in electron transfers with substrates, which results in color during oxidation. When cupric oxide nanoparticles are added to the peroxidase substrate while H2 O2 is present, a blue color product with a maximum absorbance at=652 nm can result, demonstrating the catalytic activity of a peroxidase. The morphology and composition of AA-hNFs were carefully characterized and the synthesized parameters were optimized systematically. Results showed that the nanoparticles were dispersed with an average diameter of 7-9 µm and indicated a uniform flower shape. The results of the investigation are anticipated to significantly advance a number of technical and scientific sectors.


Assuntos
Fabaceae , Nanoestruturas , Peroxidase/metabolismo , Cobre/química , Glicina , Fenilalanina , Nanoestruturas/química , Aminoácidos , Fabaceae/metabolismo , Fosfatos/química , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Chem Biodivers ; 20(9): e202300744, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37515823

RESUMO

This study, it was aimed to examine the change in the antimicrobial effect of sea anemone Parazoanthus axinellae extract by forming its nanoflowers. A scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX) were expended to observe the morphologies of the Cu NFs that had been produced. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were expended to analyze the managing assemblies in P. axinellae extract, which perform an effective part in the synthesis routine, as well as the crystal assembly of NFs. P. axinellae extract mediated the HNFs (Hybrid nanoflowers) are at high, pure crystalline nature, flower shape with a crystallographic system at the nanoscale with mean crystallite size 21.9 nm using XRD, and average particle size ~10 nm by SEM. The broad absorption band at 2981-2915 cm-1 in the FT-IR spectra of anemone extract and Cu-anemone NFs represents the unique peak of hydroxy groups. In addition, Cu NFs were tested for their antibacterial properties. Cu NFs have been discovered to exhibit antibacterial properties. It is suggested that P. axinellae extract and various inorganic components be used to synthesize a variety of NFs and assess their suitability for usage in biomedical fields.


Assuntos
Antozoários , Nanoestruturas , Animais , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Difração de Raios X
3.
Chem Biodivers ; 20(8): e202300090, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37172105

RESUMO

This work describes a unique and environmentally friendly approach for creating three-dimensional (3D) organic-inorganic flower shaped hybrid nanostructures called "nanoflower (NF)" by using Umbilicaria decussate (U. decussate) extract and copper ions (Cu2+ ). U. decussate species were collected from certain place in Antarctic and Turkey and extraction of each species were completed in methanol and water. The U. decussate extracts were used as organic components and Cu2+ acted as inorganic components for formation of U. decussate extracts based hybrid NFs. We rationally used these NFs as novel nanobiocatalyst and antimicrobial agents. These NFs exhibited peroxidase mimic, dye degradation and antimicrobial properties. The NFs were characterized with various techniques. For instance, the morphologies of the NFs were monitored by scanning electron microscope (SEM), presence of elements in the NFs were presented using Energy Dispersive X-Ray Analysis (EDX). Fourier-transform infrared spectroscopy (FT-IR) was used to elucidate corresponding bending and stretching of bonds in the NFs. The NFs acted as effective Fenton agents in the presence of hydrogen peroxide, and we demonstrated their peroxidase-like activity against guaiacol, dye degradation property towards malachite green and antimicrobial activity for Aeromonas hydrophila, Aeromonas sobria, Escherichia coli, Salmonella enterica and Staphylococcus aureus.


Assuntos
Anti-Infecciosos , Peroxidase , Peroxidase/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Cobre/química , Regiões Antárticas , Turquia , Anti-Infecciosos/farmacologia , Extratos Vegetais/química
4.
Environ Monit Assess ; 193(6): 346, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34013487

RESUMO

The aim of the current work is to examine the concentrations of nine heavy metals such as chromium, nickel, copper, cadmium, zinc, cobalt, iron, lead, and metal (aluminium) in two body parts (carapace and walking legs) of Liocarcinus depurator from different stations (Ilyas bey, Cide koyu, Anadolu feneri, igneada) in the western Black Sea coast of Turkey. And this study was carried out to examine morphological properties of Liocarcinus depurator in the region. The sex ratio (female/male) of 387 samples was calculated as F/M = 1:0.945. The mean carapace length and width were measured as 20.41 ± 2.41 mm and 25.10 ± 2.78 mm for female and 25.49 ± 3.33 mm and 32.32 ± 4.50 mm for male individually. The mean weight of crabs was measured as 4.09 ± 1.37 g for females and 8.33 ± 3.35 g for males. The samples were investigated trace metals by inductively coupled plasma-optical emission spectrometry (ICP-OES). Ranges over trace metals in all samples of L. depurator as follows: Cr 0.6-1.5, Mn 21-130, Cu 8-37, Zn 6-40, Cd 0.2-1.5, Pb 0.1-3.6, Co 0.1-1.1, Fe 22-160, and Ni 0.6-1 mg/kg wet wt. The walking legs and carapace/exoskeleton of female and male crabs were analyzed and contained various concentrations of Pb, Co, Ni, Cr, Cd, Fe, Cu, Zn, and Mn elements. The order of the heavy metal in all samples of L. depurator is shown as Fe > Cu > Mn > Zn > Cr > Cr > Ni > Cd > Pb > Co. In this research, metal levels of the crab samples compared between female and male and found highest mean metal concentrations in the station number 3 (Anadolu feneri) that the Al concentration in the carapace of female was 295.0 mg/kg wet wt and in the walking legs was 306.67 mg/kg wet wt, in the carapace of male was 264.4 mg/kg wet wt, and in the walking legs was 162.61 mg/kg wet wt in station number 3 (Anadolu feneri). The purpose of this work is to analyze the metal composition of this type of crab, which is abundant in the Black Sea region and is not planned to be attached to fisherman's nets, to evaluate whether it will be useful or not.


Assuntos
Braquiúros , Metais Pesados , Poluentes Químicos da Água , Animais , Mar Negro , Monitoramento Ambiental , Feminino , Masculino , Metais Pesados/análise , Turquia , Poluentes Químicos da Água/análise
5.
Indian J Microbiol ; 61(3): 324-330, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34294998

RESUMO

ABSTRACT: In this work, we synthesized blood orange peel extract-copper (II) (Cu2+) ions nanoflower (NFs) and blood orange juice extract-copper (II) (Cu2+) ions nanoflower examine their antimicrobial properties on the fish pathogen (Yersinia ruckeri). The main compounds of the blood orange peel extract and the blood orange juice extract were organic components, and the copper (II) (Cu2 +) ions were inorganic components. BOPE-Cu2 + nanoflowers are quite compact, porous, and uniform as compared to BOJE-Cu2+ nanoflowers. Scanning Electron Microscopy, Fourier Transform Infrared spectrometry, and Energy-Dispersive X-ray spectroscopy were used to observe the structures of the NFs. The findings of FT-IR show Cu-O and Cu-N bonds in NF, which may be an indicator of the development of NFs. Although the antimicrobial actions of BOPE-hNFs and BOJE-hNFs against Yersinia ruckeri (NCTC 12,268) have been confirmed.

6.
Health Inf Sci Syst ; 12(1): 32, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38685985

RESUMO

Gastrointestinal (GI) disorders, encompassing conditions like cancer and Crohn's disease, pose a significant threat to public health. Endoscopic examinations have become crucial for diagnosing and treating these disorders efficiently. However, the subjective nature of manual evaluations by gastroenterologists can lead to potential errors in disease classification. In addition, the difficulty of diagnosing diseased tissues in GI and the high similarity between classes made the subject a difficult area. Automated classification systems that use artificial intelligence to solve these problems have gained traction. Automatic detection of diseases in medical images greatly benefits in the diagnosis of diseases and reduces the time of disease detection. In this study, we suggested a new architecture to enable research on computer-assisted diagnosis and automated disease detection in GI diseases. This architecture, called Spatial-Attention ConvMixer (SAC), further developed the patch extraction technique used as the basis of the ConvMixer architecture with a spatial attention mechanism (SAM). The SAM enables the network to concentrate selectively on the most informative areas, assigning importance to each spatial location within the feature maps. We employ the Kvasir dataset to assess the accuracy of classifying GI illnesses using the SAC architecture. We compare our architecture's results with Vanilla ViT, Swin Transformer, ConvMixer, MLPMixer, ResNet50, and SqueezeNet models. Our SAC method gets 93.37% accuracy, while the other architectures get respectively 79.52%, 74.52%, 92.48%, 63.04%, 87.44%, and 85.59%. The proposed spatial attention block improves the accuracy of the ConvMixer architecture on the Kvasir, outperforming the state-of-the-art methods with an accuracy rate of 93.37%.

7.
IEEE Trans Nanobioscience ; 22(3): 523-528, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36269917

RESUMO

First time in this study, the antibacterial effects of Axinyssa digitata sponge extracts and Axinyssa digitata-based cupper hybrid nanoflowers (Cu hNFs) were evaluated. Herein, hybrid nanoflowers (Cu hNFs) were produced by combining Axinyssa digitata sponge extract with Cu2+ ions in Phosphate-buffered saline (PBS) (at pH 7.4) at room temperature for three days using green synthesis method. The shape and size of hNFs were evaluated using scanning electron microscope (SEM) images. Energy dispersive X-ray spectroscopy (EDX) mapping was used to determine the presence of Cu metals and other components. X-ray diffraction (XRD) is a non-destructive analysis method that was used to determine of the crystallographic properties of materials and the phases they contain. Fourier-transform infrared spectroscopy (FT-IR) peaks were used to discuss the presence of functional groups that played a key role in the synthesis. The Cu-hNFs had antimicrobial activity against selected microorganisms. This research is expected to provide knowledge on hNFs synthesis and antimicrobial activity application investigations using Axinyssa digitata rather than biomolecules obtained through costly and time-consuming methods.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Antibacterianos/química , Difração de Raios X , Nanopartículas Metálicas/química
8.
J Biotechnol ; 343: 96-101, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34861292

RESUMO

Herein, we report the synthesis of taurine incorporated (sulfur containing organic molecule derived from methionine and cysteine) hybrid nanoflowers (thNFs) with an intrinsic peroxidase-mimic and antimicrobial activities in the presence of H2O2. Formation of thNFs using non-enzyme molecules was for the first time and systematically studied as a function of the taurine concentration, types of metal ions (Cu2+, Fe2+ and Fe3+) and pH values of reaction solution. The peroxidase like activities of thNFs rely on Fenton-like reaction against guaiacol used as a model substrate. The efficiency of Fenton reaction can be attributed to porous structure and presence of ions of transition elements in the thNFs. The thNFs were further characterized using FTIR, XRD, SEM and EDX. The thNFs also showed remarkable antimicrobial properties against S. aureus, E. coli, B. cereus and C. albicans. We claim that nonprotein-based NFs can be considered as new generation nano-biocatalysts as an alternative to enzymes and can be used in various medicinal, biochemical, immunological, biotechnological, and industrial applications.


Assuntos
Anti-Infecciosos , Nanoestruturas , Anti-Infecciosos/farmacologia , Cobre , Escherichia coli , Peróxido de Hidrogênio , Peroxidase , Staphylococcus aureus , Taurina
9.
J Biotechnol ; 341: 155-162, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34601019

RESUMO

The essential goals of this present study are to elucidate the formation mechanism of ellagic acid rich-blackberry, BBE, (Rubus fruticosus L.) and raspberry, RBE, (Rubus idaeus L.) extracts directed silver nanoparticles and to investigate thier antimicrobial properties towards model dental pathogens E. faecalis and C. albicans compared to BBE, RBE, NaOCl, CHX and EDTA. Both %5 w/w of BBE and RBE reacted with 5 mM Ag + ions at room temperature (25 °C) under mild-stirring, the formation of BBE and RBE directed b@Ag NP and r@Ag NP was monitored over time by using an Uv-vis spectrophotometer. Both b@Ag and r@Ag NPs were also complementarily characterized with SEM and FT-IR. In terms of the antimicrobial studies, b@Ag NP, r@Ag NP, %5 BBE and RBE, 5 mM AgNO3, %5 NaOCl, %1,5 CHX and %15 EDTA were separately incubated with E. faecalis and C. albicans suspensions. The results were evaluated with student t-test using GraphPad Prism 8.0.1 statistical software (P < 0.05). While formation of b@Ag NP was confirmed with characteristic absorbance at ~435 nm in 20 min (min) of incubation, r@Ag NP did not give absorbance till 80 min owing to concentration of ellagic acid acted as a reducing and stabilizng agent for formation of the Ag NPs. Intrestingly, 50 ppm r@Ag NP inactivated ∼89% and ∼99% of E. faecalis and C. albicans cell, respectively, ∼25% and ∼40% cell inactivations for E. faecalis and C. albicans were observed respectively with 50 ppm b@Ag NP. We showed that 50 ppm r@Ag NP has effective antimicrobial property as much as mostly used %5 NaOCl and %1,5 CHX solutions.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Candida albicans , Ácido Elágico/farmacologia , Enterococcus faecalis , Frutas , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Irrigantes do Canal Radicular , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
10.
J Photochem Photobiol B ; 204: 111800, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32028188

RESUMO

Herein, we have reported the synthesis, characterization and catalytic activity of highly stable gold nanoparticles (Au NPs) using red cabbage extract (RCE) under UV irradiation. The anthocyanin groups predominantly existing in RCE play an essential role for biosynthesis of stable Au NPs. The reasons for using anthocyanins: 1) they act as chelating agents for preferentially reacting with gold ions (Au3+) to form Au3+- anthocyanin complexes, 2) as light-active reductants for reduction of Au3+ to zero valent Au0 under UV irradiation and 3) as stabilizing agent for preventing Au NPs from aggregation in high salt concentration owing to their unique salt tolerance property. We also demonstrate that how reaction time, concentration of RCE, pH value of reaction solutions and using one more reducing agent affected formation of the Au NPs. The stability of RCE Au NPs was comparatively studied with commercial (citrate stabilized) Au NPs against 100 mM salt (NaCl) solution. The RCE-Au NP showed reduction ability for conversion of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). UV-vis spectrometry, transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential (ZT) methods were utilized to characterize the Au NPs. We demonstrated that how whole RCE (anthocyanins molecules are major component) can be used as photo-active reducing and stabilizing agents to form Au NPs in a short time under UV irradiation and strong reducing agent without additional agents.


Assuntos
Brassica/química , Ouro/química , Nanopartículas Metálicas/química , Raios Ultravioleta , Antocianinas/química , Brassica/metabolismo , Catálise , Química Verde , Nitrofenóis/química , Oxirredução , Extratos Vegetais/química , Sais/química
11.
ACS Omega ; 4(20): 18637-18644, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31737823

RESUMO

We report synthesis of monodispersed, stable, and colloidal gold nanoparticles (Au NPs) using anthocyanin-riched red raspberry (Rubus idaeus), strawberry (Fragaria ananassa), and blackberry (Rubus fruticosus) extracts as functions of concentration of HAuCl4·3H2O and berries extract, reaction time, and reaction pH values (pHs) and demonstrate their unique stability in highly concentrated salt (sodium chloride, NaCl) solutions. The catecholamine group of anthocyanin molecules give preferential coordination reaction with gold ions (Au3+) for creating anthocyanin-Au3+ complexes, which may lead to initiation of nucleation for seed formation, and then, oxidation of catecholamine results in a flow of electrons from anthocyanins to Au seeds for anisotropic growth. Finally, the surface of the Au NPs is saturated with anthocyanins, and formation of monodispersed and stable Au NPs with narrow size distribution is completed. We also report the effects of some experimental parameters including concentrations of Au3+ ions and barrier extracts, reaction time, and pHs on formation of the Au NPs with rational explanations. The long-term colloidal stability of the Au NPs in the 400 mM NaCl solution was comparatively studied with commercial Au NPs (citrate capped). As results show that anthocyanin-riched berry extracts directed Au NPs we proposed here can be considered as promising and safe tools for biomedical applications owing to their highly much colloidal dispersibility and salt tolerance properties.

12.
RSC Adv ; 8(45): 25298-25303, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35539799

RESUMO

The discovery of functional organic-inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. The FNFs synthesized by an encouraging and novel approach not only showed high stabilities but also much enhanced catalytic activities as compared to free and conventionally immobilized enzymes. A recent development demonstrated that FNF formation has moved beyond the initial discovery in which enzymes and Cu2+ ions used as the organic and inorganic parts, respectively, are replaced with new organic (chitosan, amino acid and plant extracts) and inorganic (Cu2+ and Fe2+) materials. The new organic materials incorporated into FNFs act as Fenton-like agents and then show peroxidase-like activity owing to the metal ions and the porous structure of FNFs in the presence of hydrogen peroxide (H2O2). All FNFs have been widely utilized in many different scientific and industrial fields due to their greatly enhanced activities and stabilities. This review focuses primarily on the preparation, characterization, and bioanalytical applications of FNFs and explains the mechanisms of their formation and enhanced activities and stabilities.

13.
J Photochem Photobiol B ; 174: 78-83, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28756155

RESUMO

Various concentrations of Matricaria chamomilla (M. chamomilla) flower extract was used for biosynthesis of Ag NPs with different sizes, 70±5 (Ag NP-1), 52±5 (Ag NP-1) and 37±4nm (Ag NP-3), and size-specific antimicrobial activity of them was evaluated towards Gram+ Staphylococcus aureus (S. aureus), Gram- Escherichia coli (E. coli) bacteria and Candida fungus albicans (C. albicans). We also examine the formation of Ag NPs as a function of the plant extract volume, Ag ion concentration (Ag+) and reaction time. M. chamomilla flower extract at 100ppm shows mild inhibitory effect by inhibiting growth of all target pathogens. The extract mediated Ag NPs even at low concentration (6.25ppm) caused reductions in cell densities of the pathogens. The potential reasons for the highly effective inhibitory activity of the extract mediated Ag NPs are: (1) synergistic effects due to combination of M. chamomile extract and Ag NP because Ag NP is an effective germicidal and M. chamomile plant itself shows mild inhibitory property, (2) high localized concentration of M. chamomile extract due to nano scale entrapment of it on surface of Ag NP and (3) size-specific antibacterial efficacy of Ag NP because small size increases the active surface area of Ag NP, which reacting bacterial cells and increases number of extract molecules anchored on the surface of Ag NP.


Assuntos
Matricaria/química , Nanopartículas Metálicas/química , Tamanho da Partícula , Extratos Vegetais/química , Prata/química , Prata/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana
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