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1.
Chemosphere ; : 142456, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878982

RESUMO

The ecologically friendly properties, low-cost, and readily available titanium dioxide (TiO2) materials have made them a subject of considerable interest for numerous promising applications. Anatase TiO2 nanoparticles were synthesized in the current study through the utilization of a hibiscus leaf extract and the advent of TiO2-doped g-C3N4(TiCN) nanocomposites (varying 0.5 mM, 1.0 mM, 1.5 mM, and 2.0 mM) by thermal polymerization. Here, the proposed study utilized multiple analytical techniques, including UV-Vis spectroscopy, a diffraction pattern (XRD), SEM coupled with EDX analysis, TGA, and EPR, to characterize the as-prepared TiO2 nanoparticles and TiCN nanocomposites.BET analysis the adsorption-desorption isotherms of the TiCN(1.5mM) nanocomposite, the surface area of the prepared nanocomposite is 112.287 m2/g, and the pore size is 7.056 nm. The XPS spectra support the development of the TiCN(1.5mM) nanocomposite by demonstrating the presence of C and N elements in the nanocomposite in addition to TiO2.HRTEM images where the formation of stacked that indicates a planar, wrinkled graphitic-like structure is clearly visible. The TiCN (1.5 mM) specimen exhibited enhanced morphology, enhanced surface area, greater capacity to take in visible light, and lowered band gap when compared to g-C3N4 following z-scheme heterojunction. The sample denoted as TiCN (1.5 mM) exhibited superior performance in terms of adsorption and photocatalytic activity using rhodamine B and Bisphenol A. Furthermore, the TiCN (1.5 mM) composite exhibited satisfactory stability over four cyclic runs, indicating its potential application in minimizing the impact of organic wastewater contaminants when compared to g-C3N4.

2.
Chemosphere ; 345: 140452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852386

RESUMO

Dealing harmful dye-containing effluent from the textile sector significantly contributes to water contamination. The persistence of these dyes in wastewater complicates traditional treatment approaches, emphasizing the necessity for efficient photocatalytic materials for dye pollution degradation. Due to its unique features, V2O5/g-C3N4 nanocomposites are discovered as promising photocatalysts in this area. The V205 nanoparticles act as electron acceptors, while g-C3N4 acts as electron donors, thus encouraging charge separation and increasing photocatalytic activity. The V2O5/g-C3N4 nanocomposites are characterized using XRD, FTIR spectroscopy, SEM, TEM, XPS, and UV-DRS. Cationic dyes, anionic dyes and mix dyes (1:1 mixture of cationic and anionic dyes) are used to test the photocatalytic activity of the nanocomposites. Photocatalytic activity shows that V2O5/g-C3N4 nanocomposites are more active than their precursors. The V5G-2 nanocomposite degrades anionic (Rose Bengal (85.1%) and Xylenol Orange (77.6%), cationic (Auramine O (75% and Crystal Violet (79.5%), and mixed dyes (81%), after 120 min of irradiation. This study introduces a novel technique for synthesizing V2O5/g-C3N4 nanocomposites using solvothermal and ultrasonic processes. The findings of this research provide significant knowledge for the development of photocatalysts with enhanced efficiency in the degradation of dye pollutants.


Assuntos
Nanocompostos , Águas Residuárias , Corantes , Catálise , Luz , Nanocompostos/química
3.
Chemosphere ; 339: 139707, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37536534

RESUMO

The research reported here emphasizes the phytoextract route synthesized ZnO-doped g-C3N4 (GCN) for its photocatalytic activity, which helps to ensure a sustained & healthy environment. The leaf extract solution of Ficus Benjamina L. was used for the synthesis of ZnO nanoparticles, and GCN was prepared via urea using a thermal polymerization process. The flower extract functions as both stabilizers and capping agents during the process of synthesis of ZnO nanoparticles. The synthesized nanocomposites were then calcined at 400 °C and were further characterized with spectroscopy (UV-Vis), diffracted pattern (XRD), and infrared spectroscopy (FTIR). Further, the photocatalytic activity of auramine orange (AO) and methylene blue (MB) dye from phytoextract route synthesized pure ZnO NPs, GCN-Pure, and composites with varied millimolar concentrations of ZnO nanoparticles with GCN of the constant amount was checked. After the complete analysis, it was observed that the series that was prepared of ZnO-GCN nanocomposites showed notable enhancement in the degradation pattern of the methylene blue dye. Apparently, 1.5 mmol (mM) ZnO-GCN presented greater degradation patterns for Auramine orange and Methylene blue dye as compared to other nanocomposites that were synthesized. The observed increased photocatalytic activity has a conceivable explanation. The antibacterial activity studies of the prepared nanocomposites were also performed against the E. coli strain showing an enhanced zone of inhibition towards it.


Assuntos
Ficus , Nanocompostos , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Azul de Metileno/farmacologia , Azul de Metileno/química , Escherichia coli , Benzofenoneídio , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química
4.
J Biomol Struct Dyn ; : 1-14, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37293950

RESUMO

The drugs fighting against aggressive fungal infections are in limited number, therefore, extensive research is obligatory to develop new therapeutic strategies. Fluconazole (FLZ) is a clinically approved drug, but resistant drug against most fungal pathogens, thus it is vital to identify more compounds that can better check the fungal growth. Analogue-based drug designing is a quick and economical way since it has inherent drug-like properties of marketed drugs. This study aims to generate and evaluate analogues of FLZ with better potency against fungal-borne infections. A total of 3307 analogues of FLZ were developed from six scaffold structures. Only 390 compounds passed Lipinski's rule, of which 247 analogues exhibited lower docking scores than FLZ with 5FSA. These inhibitors were further subjected to pharmacokinetics property evaluation and cytotoxicity test and it was found that only 46 analogues were suitable for further evaluation. Based on the molecular docking score of the best two analogues, 6f (-12.7 kcal/mol) and 8f (-12.8 kcal/mol) were selected for molecular dynamics and in-vitro studies. Antifungal activities of both compounds against 4 strains of Candida albicans were evaluated by disc diffusion assay and micro broth dilution assay and Minimum inhibitory concentrations (MICs) for 6f and 8f were observed as 256 µg/ml against 4719, 4918 and 5480 strains but the MIC was extended to 512 µg/ml for strain 3719. Both analogues exhibited low antifungal activities as compared to FLZ (8-16 µg/ml). The interaction of 6f with Mycostatin was also performed using a chequerboard assay that was found additive.Communicated by Ramaswamy H. Sarma.

5.
Environ Sci Pollut Res Int ; 30(10): 25650-25662, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36696062

RESUMO

The present work focuses on the green synthesis of Ag-doped graphitic carbon nitride (Ag@GCN) for photocatalytic activities, which can contribute to a more sustainable environment. The leaf extract of the Ocimum tenuiflorum (Tulsi) plant was used to prepare the silver nanoparticles, as the plant extract serves as a stabilizing and capping agent in producing silver nanoparticles. Both Ag nanoparticles and urea-derived GCN were synthesized by thermal polymerization. The Ag-doped GCN nanocomposites were synthesized using various millimolar concentrations of Ag nanoparticles (NPs) with a fixed amount of GCN. The green nanocomposites (NCs) were synthesized by calcinating leaf extract at about 550 °C. They were then characterized for surface morphology by SEM coupled with energy-dispersive X-ray spectroscopy (EDX), and elemental composition by XRD, Fourier-dispersive infrared spectroscopy (FTIR), and transmission electron microscope (TEM). Thermal stability and estimation of the Ag content in GCN were done through thermogravimetric analysis. The prepared series of nanocomposites (Ag-doped GCN 0.5 mM, 1.0 mM, 1.5 mM, 2.0 mM) were used to study the photocatalytic degradation efficiency of rose bengal (RB) and xylenol orange (XO) dyes. The degradation efficiency of dyes gets enhanced due to the doping of Ag nanoparticles into GCN. The efficiency increased from 54 to 76% and 15 to 36% in the case of RB and XO dyes, respectively. The apparent rate constant value increased up to 2.5 times in the case of the Ag-doped GCN (1.5 mM) nanocomposite in comparison to GCN. The result obtained from the study confirmed that Ag-doped GCN (1.5 mM) could act as a potential photocatalyst for wastewater remediation applications.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Corantes , Prata/química , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Curr Drug Targets ; 23(16): 1465-1488, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35748549

RESUMO

Now-a-days fungal infection emerges as a significant problem to healthcare management systems due to high frequency of associated morbidity, mortality toxicity, drug-drug interactions, and resistance of the antifungal agents. Aspergillus is the most common mold that cause infection in immunocompromised hosts. It's a hyaline mold that is cosmopolitan and ubiquitous in nature. Aspergillus infects around 10 million population each year with a mortality rate of 30-90%. Clinically available antifungal formulations are restricted to four classes (i.e., polyene, triazole, echinocandin, and allylamine), and each of them have their own limitations associated with the activity spectrum, the emergence of resistance, and toxicity. Consequently, novel antifungal agents with modified and altered chemical structures are required to combat these invasive fungal infections. To overcome these limitations, there is an urgent need for new antifungal agents that can act as potent drugs in near future. Currently, some compounds have shown effective antifungal activity. In this review article, we have discussed all potential antifungal therapies that contain old antifungal drugs, combination therapies, and recent novel antifungal formulations, with a focus on the Aspergillus associated infections.


Assuntos
Antifúngicos , Aspergilose , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Aspergillus , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Micoses/tratamento farmacológico
7.
Mini Rev Med Chem ; 22(1): 26-42, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33797362

RESUMO

Staphylococcus aureus is a prominent human pathogen that causes nosocomial and community acquired infections. The accelerating emergence and prevalence of staphylococcal infections have grotesque health consequences which are mostly due to its anomalous capability to acquire drug resistance and scarcity of novel classes of antibacterials. Many combating therapies are centered on primary targets of S. aureus which are cell envelope, ribosomes and nucleic acids. This review describes various chemotherapeutic strategies for combating S. aureus infections including monotherapy, combination drug therapy, phage endolysin therapy, lysostaphins and antibacterial drones. Monotherapy has dwindled in due course of time, but combination therapy, endolysin therapy, lysostaphin and antibacterial drones are emerging alternatives which efficiently conquer the shortcomings of monotherapy. Combinations of more than one antibiotic agents or combination of adjuvant with antibiotics provide a synergistic approach to combat infections causing pathogenic strains. Phage endolysin therapy and lysostaphin are also presented as possible alternatives to conventional antibiotic therapies. Antibacterial Drones go a step further by specifically targeting the virulence genes in bacteria, giving them a certain advantage over existing antibacterial strategies. But the challenge remains on the better understanding of these strategies for executing and implementing them in the health sector. In this day and age, most of the S. aureus strains are resistant to an ample number of antibiotics, so there is an urgent need to overcome such multidrug-resistant strains for the welfare of our community.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Humanos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia
8.
Curr Drug Targets ; 23(2): 116-125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34551694

RESUMO

Fungal infections have shown an upsurge in recent decades, which is mainly because of the increasing number of immunocompromised patients and the occurrence of invasive candidiasis has been found to be 7-15 fold greater than that of invasive aspergillosis. The genus Candida comprises more than 150 distinct species, however, only a few of them are found to be pathogenic to humans. Mortality rates of Candida species are found to be around 45% and the reasons for this intensified mortality are inefficient diagnostic techniques and unfitting initial treatment strategies. There are only a few antifungal drug classes that are employed for the remedy of invasive fungal infections. which include azoles, polyenes, echinocandins, and pyrimidine analogs. During the last 2-3 decades, the usage of antifungal drugs has increased several folds due to which the reports of escalating antifungal drug resistance have also been recorded. The resistance is mostly to the triazole- based compounds. Due to the occurrence of antifungal drug resistance, the success rates of treatment have been reduced as well as major changes have been observed in the frequency of fungal infections. In this review, we have summarized the major molecular mechanisms for the development of antifungal drug resistance.


Assuntos
Candida , Micoses , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico
9.
Curr Drug Targets ; 22(12): 1334-1345, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33494671

RESUMO

The escalating emergence and prevalence of infections caused by multi-drug resistant (MDR) pathogenic bacteria accentuate the crucial need to develop novel and effectual therapeutic strategies to control this threat. The recent past surprisingly indicates a staggering decline in effective strategies against MDR. Different approaches have been employed to minimize the effect of resistance, but the question still lingers over the astounding number of drugs already tried and tested. Furthermore, the detection of new drug targets and the action of new antibacterial agents against already existing drug targets also complicate the condition. Antibiotic adjuvants are considered as one such promising approach for overcoming bacterial resistance. Adjuvants can potentiate the action of generally adopted antibacterial drugs against MDR bacterial pathogens either by minimizing the impact and emergence of resistance or improving the action of antibacterial drugs. This review provides an overview of the mechanism of antibiotic resistance, the main types of adjuvants and their mode of action, achievements and progression.


Assuntos
Antibacterianos , Infecções Bacterianas , Farmacorresistência Bacteriana Múltipla , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos
10.
Curr Drug Targets ; 21(4): 365-373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31549952

RESUMO

The existence of the multi-drug resistant (MDR) pathogenic fungus, Candida auris came to light in 2009. This particular organism is capable of causing nosocomial infections in immunecompromised persons. This pathogen is associated with consistent candidemia with high mortality rate and presents a serious global health threat. Whole genome sequence (WGS) investigation detected powerful phylogeographic Candida auris genotypes which are specialized to particular geological areas indicating dissemination of particular genotype among provinces. Furthermore, this organism frequently exhibits multidrug-resistance and displays an unusual sensitivity profile. Identification techniques that are commercialized to test Candida auris often show inconsistent results and this misidentification leads to treatment failure which complicates the management of candidiasis. Till date, Candida auris has been progressively recorded from several countries and therefore its preventive control measures are paramount to interrupt its transmission. In this review, we discussed prevalence, biology, drug-resistance phenomena, virulence factors and management of Candida auris infections.


Assuntos
Candida/genética , Candida/patogenicidade , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Adolescente , Adulto , Idoso , Antifúngicos/farmacologia , Candida/citologia , Candida/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/prevenção & controle , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Farmacorresistência Fúngica Múltipla/genética , Farmacorresistência Fúngica Múltipla/fisiologia , Feminino , Saúde Global , Humanos , Lactente , Recém-Nascido , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores de Virulência , Adulto Jovem
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