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1.
J Environ Manage ; 365: 121644, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38963970

RESUMO

The Earth's atmosphere contains ultrafine particles known as aerosols, which can be either liquid or solid particles suspended in gas. These aerosols originate from both natural sources and human activities, termed primary and secondary sources respectively. They have significant impacts on the environment, particularly when they transform into ultrafine particles or aerosol nanoparticles, due to their extremely fine atomic structure. With this context in mind, this review aims to elucidate the fundamentals of atmospheric-derived aerosol nanoparticles, covering their various sources, impacts, and methods for control and management. Natural sources such as marine, volcanic, dust, and bioaerosols are discussed, along with anthropogenic sources like the combustion of fossil fuels, biomass, and industrial waste. Aerosol nanoparticles can have several detrimental effects on ecosystems, prompting the exploration and analysis of eco-friendly, sustainable technologies for their removal or mitigation.Despite the adverse effects highlighted in the review, attention is also given to the generation of aerosol-derived atmospheric nanoparticles from biomass sources. This finding provides valuable scientific evidence and background for researchers in fields such as epidemiology, aerobiology, and toxicology, particularly concerning atmospheric nanoparticles.

2.
Comput Biol Chem ; 112: 108134, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38964206

RESUMO

Global public health is confronted with significant challenges due to the prevalence of cancer and the emergence of treatment resistance. This work focuses on the identification of cyclin-dependent kinase 2 (CDK2) through a systematic computational approach to discover novel cancer therapeutics. A ligand-based pharmacophore model was initially developed using a training set of seven potent CDK2 inhibitors. The obtained most robust model was characterized by three features: one donor (|Don|) and two acceptors (|Acc|). Screening this model against the ZINC database resulted in identifying 108 hits, which underwent further molecular docking studies. The docking results indicated binding affinity, with energy values ranging from -6.59 kcal mol⁻¹ to -7.40 kcal mol⁻¹ compared to the standard Roscovitine. The top 10 compounds (Z1-Z10) selected from the docking data were further screened for ADMET profiling, ensuring their compliance with pharmacokinetic and toxicological criteria. The top 3 compounds (Z1-Z3) chosen from the docking were subjected to Density Functional Theory (DFT) studies. They revealed significant variations in electronic properties, providing insights into the reactivity, stability, and polarity of these compounds. Molecular dynamics simulations confirmed the stability of the ligand-protein complexes, with acceptable RMSD and RMSF values. Specifically, compound Z1 demonstrated stability, around 2.4 Å, and maintained throughout the 100 ns simulation period with minimal conformational changes, stable RMSD, and consistent protein-ligand interactions.

3.
Comput Biol Chem ; 110: 108073, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38678727

RESUMO

Human Carbonic anhydrase IX (hCA IX) is found to be an essential biomarker for the treatment of hypoxic tumors in both the early and metastatic stages of cancer. Due to its active function in maintaining pH levels and overexpression in hypoxic conditions, hCA IX inhibitors can be a potential candidate specifically designed to target cancer development at various stages. In search of selective hCA IX inhibitors, we developed a pharmacophore model from the existing natural product inhibitors with IC50 values less than 50 nm. The identified hit molecules were then investigated on protein-ligand interactions using molecular docking experiments followed by molecular dynamics simulations. Among the zinc database 186 hits with an RMSD value less than 1 were obtained, indicating good contact with key residues HIS94, HIS96, HIS119, THR199, and ZN301 required for optimum activity. The top three compounds were subjected to molecular dynamics simulations for 100 ns to know the protein-ligand complex stability. Based on the obtained MD simulation results, binding free energies are calculated. Density Functional Theory (DFT) studies confirmed the energy variation between the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). The current study has led to the discovery of lead compounds that show considerable promise as hCA IX inhibitors and suggests that three compounds with special molecular features are more likely to be better-inhibiting hCA IX. Compound S35, characterized by a higher stability margin and a smaller energy gap in quantum studies, is an ideal candidate for selective inhibition of CA IX.


Assuntos
Antígenos de Neoplasias , Anidrase Carbônica IX , Inibidores da Anidrase Carbônica , Teoria da Densidade Funcional , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Anidrase Carbônica IX/antagonistas & inibidores , Anidrase Carbônica IX/metabolismo , Anidrase Carbônica IX/química , Humanos , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/química , Estrutura Molecular , Ligantes , Farmacóforo
4.
Environ Res ; 238(Pt 1): 117090, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37683791

RESUMO

The present study is aimed to evaluate pesticidal activity and biocompatibility including ecotoxicity of functionalized silica nanoparticles that synthesized by simple, in vitro, green technology principles. Sol-gel method was adopted for the synthesis of silica nanoparticles and was functionalized by Aminopropyltriethoxysilane (APS), characterized and confirmed the uniform, monodispersive, highly stable particles with the size range of 10-200 nm. The synthesized Nano silica was screened against the developmental stages of Spodoptera litura. Pesticidal study revealed that the functionalized nanoparticles were effective against all the life stages of the insect by recording high mortality and the drastic reduction in the larval, pupae, adult emergence, and adult longevity stages. The ecotoxic effect of synthesized nano-silica was tested on soil parameters, growth parameters of Arachis hypogaea, and compatibility with Trichoderma viride. This study revealed there was no toxic effect on soil, growth parameters of Arachis hypogaea, and most significantly the growth of Trichoderma viride was not inhibited. A biocompatibility study was done by using Zebrafish and Rabbit model. The study divulges there was no toxic effect on all the developmental stages of the Embryo. Further, the nanoparticles did not exhibit any dermatotoxicological effect which confirmed no signs and symptoms of inflammation. Nano-silica emerges as a promising eco-friendly and non-toxic substitute for conventional insecticides. Its utilization has the potential to augment both environmental preservation and economic prosperity on a national scale. Furthermore, the integration of silica-based nanoparticles with biocidal agents demonstrates notable biocompatibility and the capacity to hinder bacterial adhesion.


Assuntos
Nanopartículas , Praguicidas , Animais , Coelhos , Dióxido de Silício/toxicidade , Peixe-Zebra , Nanopartículas/toxicidade , Solo
5.
Environ Res ; 231(Pt 2): 116150, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209987

RESUMO

The present study evaluates the biocompatibility of silver and zinc oxide nanoparticles with various effective microorganisms (EM), like beneficial microbial formulations. The respective nanoparticle was synthesised by chemical reduction of metal precursor with reducer via simple route green technology principles. The synthesised nanoparticles were characterised by UV visible spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) studies, revealing highly stable, nanoscale particles with marked crystallinity. EM-like beneficial cultures composed of viable cells of Lactobacillus lactis, Streptomyces sp, Candida lipolytica, and Aspergillus oryzae were formulated with rice bran, sugarcane syrup, and groundnut cake. The respective formulation was inoculated into the nanoparticles amalgamated pots raised with green gram seedlings. Biocompatibility was determined by measuring plant growth parameters of a green gram at pre-determined periods associated with enzymatic antioxidants like catalase (CAT), superoxide dismutase (SOD), and glutathione S transferase (GST) levels. Most significantly, the expression level of these enzymatic antioxidants level was also investigated by quantitative real-time polymerase chain reaction (qRT-PCR). The impact of the soil conditioning effect on soil nutrients like nitrogen, phosphorous, potassium, organic carbon, soil enzymes glucosidases, and ß-xylosidases activity was also studied. Among the formulation, rice bran-groundnut cake-sugar syrup formulation recorded the best biocompatibility. This formulation showed high growth promotion, soil conditioning effect and no impact on the oxidative stress enzymes genes that revealed the best compatibility of nanoparticles. This study concluded that biocompatible, eco-friendly formulations of microbial inoculants could be used for the desirable agro active properties that show extreme tolerance or biocompatibility to the nanoparticles. This present study also suggests the utilisation of the above said beneficial microbial formulation and metal-based nanoparticles with desirable agro active properties in a synergistic manner due to their high tolerance or compatibility towards the metal or metal oxide nanoparticles.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Antioxidantes/metabolismo , Óxidos , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Estresse Oxidativo , Óxido de Zinco/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
6.
Chemosphere ; 308(Pt 2): 135950, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36075361

RESUMO

Nanomaterials mainly nanocomposites possess unique physical and chemical properties which makes them superior and indispensable. Though much research has been focused on the properties and application of nanocomposites, the eco-toxicity assessment is one among top priority, which aims to protect the population of concerned biological component and their ecosystem. With this objective, the present study has undertaken an initiation to evaluate the efficacy of chitosan-silver nanocomposite for methyl orange adsorption property (CS-AgNC) and also assessed the toxicity impact on growth parameters of freshwater Tilapia. Batch in vitro studies showed that all the tested dosages of the nanocomposite were effectively adsorbing maximum concentration of methyl orange. The synthesized nanocomposite was administrated to the tested fishes followed by the determination of various growth, nutritional parameters, gene expression of enzymatic antioxidants and liver, and intestinal tissues histology. Obtained results indicated that nanocomposite treatment was not projected as a toxic impact on all the tested growth, and nutritional parameters. Histology study showed that the exposure of Tilapia to nanocomposite has not shown any detrimental effect on antioxidants gene expression and liver, intestinal tissue architecture. Hence, all these findings indicated that chitosan-silver nanocomposite prepared in our present system was found to be biocompatible which suggested the possible utilization and release of the nanocomposite into the divergent ecosystem without affecting non-target organisms (NTO).


Assuntos
Quitosana , Nanocompostos , Tilápia , Adsorção , Animais , Compostos Azo , Quitosana/química , Ecossistema , Água Doce , Nanocompostos/química , Nanocompostos/toxicidade , Prata/química , Prata/toxicidade
7.
Environ Res ; 212(Pt C): 113386, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35569536

RESUMO

In this present study, a highly stable gum acacia -gold nanocomposite fabricated with food preservative agent natamycin (GA-AuNC-NT) was prepared via green science principles under in vitro conditions. Various characterisation techniques reveal highly stable structural, functional properties of the synthesised nanocomposite with marked antifungal activity and adsorption efficacy against congo red dye. The antifungal activity was investigated against the fungal strain Aspergillus ochraceopealiformis isolated from spoiled, expired bread. The well diffusion assay, fungal hyphae fragmentation assay and spore germination inhibition assay were used to determine the antifungal activity of the synthesised nanocomposite. Potential antifungal activity of the synthesised nanocomposite was confirmed by recording zone of inhibition, high rate of hyphae fragmentation and marked spore germination inhibition against the tested fungal strain. The molecular mechanism of antifungal activity was studied by measuring oxidative stress marker genes like catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) induction adopting quantitative real-time polymerase chain reaction (q RT-PCR). Among the various treatment, a notable reduction in all the tested marker genes expression was recorded in the nanocomposite treated fungal strain. Release profile studies using different solvents reveals sustained or controlled release of natamycin at the increasing periods. The synthesised nanocomposite's high safety or biocompatibility was evaluated with the Wistar animal model by determining notable changes in behavioural, biochemical, haematological and histopathological parameters. The synthesised nanocomposite did not exhibit any undesirable changes in all the tested parameters confirming the marked biosafety or biocompatibility. The nanocomposite was coated on the bread packaging material. The effect of packaging on the proximate composition, antioxidative enzymes status, and fungal growth of bread samples incubated under the incubation period were studied. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies reveal that the nanocomposite was effectively coated on the packaging material without changing size, shape, and functional groups. No changes in the proximate composition and antioxidative enzymes of the packaged bread samples incubated under different incubation periods reveal the nanocomposite's marked safety. The complete absence of the fungal growth also indicates the uniqueness of the nanocomposite. Further, the sorption studies revealed the utilisation of Langmuir mechanism and pseudo II order model successfully The present finding implies that the synthesised nanocomposite can be used as an effective, safe food preservative agent and adsorbent of toxic chemicals.


Assuntos
Vermelho Congo , Nanocompostos , Adsorção , Animais , Antifúngicos/farmacologia , Aspergillus , Conservantes de Alimentos , Fungos , Ouro , Goma Arábica , Nanocompostos/química , Natamicina/farmacologia
8.
IET Nanobiotechnol ; 15(1): 117-134, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34694724

RESUMO

A laboratory experiment was conducted to evaluate enhanced pesticidal activity of silica nanoparticles-doped chitinase nano enzyme conjugate against an economically important insect pest Spodoptera litura (Fab.) (Lepidoptera; Noctuidae). Silica nanoparticles were synthesized by hydrolysis and condensation of precursor tetraethylorthosilicate (TEOS) followed by functionalization with functioning agent 3-aminopropyltriethoxysilane. Functionalized silica nanoparticles thus acquired were doped with chitinase enzyme produced by Serratia marcescens SU05. Doped nanosilica-chitinase nano enzyme conjugate was loaded with pesticidal plant extracts to study the improved pesticidal activity. Synthesized nano enzyme conjugate revealed high stable, monodisperse spherical nanoparticles and exhibited effective loading with respective plant extracts. Nano enzyme conjugates and plant extracts loaded with nano enzyme conjugate recorded high rate of mortality against the larval instars and brought about a distinct effect on the life stage parameters of S.litura. Non-target toxic effect of nano enzyme conjugate was carried out by determination of lethality and changes in protein profiling against brine shrimp (Artemia salina) that shows less lethality and no distinct changes in protein profiling which suggest the effective utilization of silica nanoparticles doped chitinase as an insecticidal agent against economically important insect pests associated with various crops.


Assuntos
Quitinases , Praguicidas , Animais , Larva , Extratos Vegetais/farmacologia , Spodoptera
9.
Microb Pathog ; 148: 104412, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798672

RESUMO

Pseudomonas aeruginosa- major group of an aerobic bacteria associated with nosocomial and other life threatening infections. Diverse virulence factors produced by P. aeruginosa is due to distinct molecular cell signaling mechanism termed as quorum sensing (QS). Interfering with normal QS mechanism by active biomolecules is an effective strategy for attenuating its virulence. With this objective, the present study is undertaken to evaluate the inhibition of quorum sensing of clinical isolate of P. aeruginosa by repression of Las R-a transcriptional regulator for QS by ethanol extract of Terminalia chebula and Ficus racemosa. Las R repression by the plant extracts was measured in inhibition of various virulence factors like biofilm, pyocyanin production, total proteolytic activity, swarming and twisting motility. Fabrication of the extracted metabolites on the wound dressing and its effect on anti bacterial activity was also investigated. Compatibility of plant extracts on zebra fish development and blood cells was further studied. P. aeruginosa was isolated from the post operative patient and the isolated pure culture was identified by cultural, biochemical, molecular characteristics. Active principles of both the plants were readily extracted in ethanol and effectively repressed the expression of Las R. Both the tested plant extracts effectively repressed Las R expression which in turn affect the production of various virulence factors like biofilm formation, pyocyanin production, swarming motility, twisting motility, total proteolytic activity, cell adhesion and signaling molecule acyl honoserine lactone (AHL) production. Plant extract treatment brought about drastic reduction of all the tested virulence factors and AHL production. Extracted metabolites were fabricated on the wound dressing material adopting simple dip or immersion method reveals uniform coating, effective embedding of phytochemicals with the fibers and retained the anti bacterial activity against P. aeruginosa. Biocompatibility studies with zebra fish model shows both the tested plant extracts treatment was not exhibited any sign of toxicity on the developmental stages of Zebra fish. Hemolysis and changes in anti oxidative enzymes were not recorded in the plant extracts treated blood which demonstrated the best biocompatibility of the tested plant extracts. These results shows that the presence of potential phytochemicals in the ethanolic extract of Terminalia chebula and Ficus racemosa effectively represses the Las R followed by inhibition of quorum sensing mediated virulence factors production may be useful in the lead of anti bacterial drugs.


Assuntos
Antibacterianos/farmacologia , Ficus/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Terminalia/química , Animais , Biofilmes , Humanos , Percepção de Quorum/efeitos dos fármacos , Fatores de Virulência
10.
Int J Biol Macromol ; 120(Pt A): 921-944, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30172810

RESUMO

In the present study, enhanced pesticidal activity and biocompatibility of chitosan nanocomposite prepared with biocompatible polymer chitosan - insecticidal metabolites derived from potential fungal biopesticidal agent Nomuraea rileyi were studied. Insecticidal metabolites were isolated from the culture filtrate of fungal strain grown in sabouraud maltose yeast extract broth (SMYB) and the collected filtrate was extracted with ethyl acetate followed by purification using G-60 silica gel column. Chitosan nanocomposite was prepared with metabolites thus acquired by ionic gelation method. Synthesized nanocomposite was found to have high stability, uniformly dispersed particles with high loading and entrapment efficiency. Insecticidal activity was studied by determination of cumulative mortality against larval instars of Spodoptera litura and changes in biochemical composition of midgut, hemolymph macromolecules which revealed that the nanocomposite was effective against all the larval stages in terms of high mortality, drastic reduction of midgut and hemolymph macromolecules biochemical composition. Biocompatibility of nanocomposite was carried out by evaluation of developmental toxicity against zebrafish and in vitro hemolysis with peripheral blood cells. Chitosan nanocomposite treatment was not induced any toxic effect on the developmental stages of zebra fish. Hemolysis was also not recorded in the nanocomposite treatment. The observed results imply that insecticidal metabolites fabricated chitosan nanocomposite prepared in our present system is a promising candidates for pest control against economically important insect pests without affecting non-target organisms.


Assuntos
Quitosana/química , Inseticidas/química , Nanocompostos/química , Praguicidas/química , Spodoptera/efeitos dos fármacos , Animais , Quitosana/farmacologia , Fungos/química , Insetos/efeitos dos fármacos , Insetos/patogenicidade , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/patogenicidade , Praguicidas/farmacologia , Spodoptera/patogenicidade
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