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1.
Appl Biochem Biotechnol ; 195(2): 1541-1573, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36222988

RESUMO

In the current scenario of the coronavirus pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), considerable efforts have been made to control the pandemic by the development of a strong immune system through massive vaccination. Just after the discovery of the genetic sequences of SARS-CoV-2, the development of vaccines became the prime focus of scientists around the globe. About 200 SARS-CoV-2 candidate vaccines have already been entered into preclinical and clinical trials. Various traditional and novel approaches are being utilized as a broad range of platforms. Viral vector (replicating and non-replicating), nucleic acid (DNA and RNA), recombinant protein, virus-like particle, peptide, live attenuated virus, an inactivated virus approaches are the prominent attributes of the vaccine development. This review article includes the current knowledge about the platforms used for the development of different vaccines, their working principles, their efficacy, and the impacts of COVID-19 vaccines on thrombosis. We provide a detailed description of the vaccines that are already approved by administrative authorities. Moreover, various strategies utilized in the development of emerging vaccines that are in the trial phases along with their mode of delivery have been discussed along with their effect on thrombosis and gastrointestinal disorders.


Assuntos
COVID-19 , Gastroenteropatias , Trombose , Vacinas Virais , Humanos , Vacinas contra COVID-19 , COVID-19/prevenção & controle , SARS-CoV-2/genética , Vacinas Virais/uso terapêutico , Gastroenteropatias/prevenção & controle , Gastroenteropatias/tratamento farmacológico , Trombose/prevenção & controle , Trombose/tratamento farmacológico
2.
Appl Biochem Biotechnol ; 194(5): 2005-2020, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35006551

RESUMO

The present work describes the bio-based green synthesis and characterization of zinc oxide nanoparticles (ZnO NPs) using leaf extract of Tridax procumbens; the synthesized nanoparticles were used to study their beneficial effect on the growth and metabolism of Vigna radiata. ZnO NPs were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and ultraviolet-visible spectroscopy (UV-Vis spectra). Growth of V. radiata seedlings was measured in terms of shoot length and root length that were treated 20 and 40 mg/L concentrations of green synthesized ZnO NPs and constant concentration (50 mg/L) of PbCl2. These studies have shown the effect of ZnO NPs in the stimulation of growth as well as physiological and biochemical parameters. Vigna seedlings showed positive effects depending upon the increasing concentrations of ZnO NPs. This study suggests that ZnO NPs can be effectively used to ameliorate the toxicity of Pb in Vigna plants.


Assuntos
Nanopartículas Metálicas , Vigna , Óxido de Zinco , Antibacterianos/química , Química Verde , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Óxidos , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Óxido de Zinco/química , Óxido de Zinco/toxicidade
3.
J Biotechnol ; 343: 83-95, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34864124

RESUMO

Beginning of industrialization accelerates the heavy metal pollution in the biosphere. Plant being the immovable entity utilizes different mechanisms to flee from unfavourable conditions. To alleviate toxic impact of metals like cadmium (Cd) and lead (Pb), phytohormones such as indole acetic acid (IAA) has been applied exogenously. This manuscript aims to evaluate the significant change occurring in biochemical parameters of Indian mustard (Brassica napus) grown under individual and combined treatments of IAA with Cd and Pb. Herbicidal potential of treated Brassica extracts were evaluated on growth and development of Anagallis arvensis. Quantum yield parameters were more sensitive to Cd than Pb stress resulted in reduced photosynthetic pigments. However, exogenously applied IAA together with Cd and Pb considerably improved the level of photosynthetic attributes along with reduced accumulation of Cd and Pb in Brassica plant. Cd and Pb enhanced the activities of reactive oxygen species (ROS) and antioxidant machinery. However, addition of IAA with Cd and Pb mitigated the effect of heavy metals on antioxidant system. Moreover, activity of the phenylalanine ammonia lyase enzyme and the defensive metabolites (phenolic, flavonoid and anthocyanin compounds) were boosted under individual treatments of Cd and Pb responsible for increasing herbicidal potential of Brassica plant. Our results exhibited essentiality of IAA in mitigating Cd and Pb stress in Brassica through up-regulated mechanisms of the antioxidant system for balancing ROS related injuries. Increased metabolites enhancing herbicidal potential of Brassica napus against Anagallis weed were also observed.


Assuntos
Anagallis/crescimento & desenvolvimento , Brassica napus , Herbicidas , Poluentes do Solo , Brassica napus/metabolismo , Cádmio/toxicidade , Ácidos Indolacéticos , Chumbo/toxicidade , Compostos Fitoquímicos , Plantas Daninhas/crescimento & desenvolvimento , Poluentes do Solo/toxicidade
4.
Ecotoxicol Environ Saf ; 182: 109410, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31284122

RESUMO

Cerium oxide nanoparticles (nanoceria) were synthesized by a novel, simple green chemistry procedure using Elaeagnus angustifolia leaf extract as a reducing and capping agent. The crystalline nature of nanoceria was confirmed by XRD analysis. FTIR analysis revealed that phytochemicals are present on the surface of nanoceria. SEM and TEM images revealed that the nanoceria are well dispersed, spherical in shape with a particle size range in between 30 and 75 nm. Thereafter, the effects of various concentrations of cerium oxide (CeO2) and green synthesized nanoceria on growth and metabolism of Solanum lycopersicum (tomato) were investigated. The bio-accumulation of Ce in tomato seedlings was found to be dose dependent and the results showed that with the increase in exposure concentrations, the accumulation of Ce contents in both root and shoots augmented. However, unlike nanoceria treated seedlings, Ce contents in the roots with CeO2 treatments were negligible than that in the shoots at lower concentrations and this suggested the immobilization of Ce in CeO2 treatment at lower concentrations. Nanoceria at 500 and 1000 mg/L resulted in inhibitory effect on growth of test plant as compared to CeO2 component. The exposure of plants to nanoceria and CeO2 has resulted in significant reduction in pigment content, increased LP, EL and H2O2 content. The activities of antioxidant enzymes viz. SOD, CAT, APX and GPX were significantly up regulated on exposure of nanoceria and CeO2. It is concluded that plant exposure with nanoceria at concentrations of 20 and 100 mg/L were more beneficial for growth and metabolism of tomato plants than that of CeO2 at equivalent concentrations.


Assuntos
Antioxidantes/metabolismo , Cério/farmacologia , Química Verde/métodos , Nanopartículas/química , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/enzimologia , Transporte Biológico , Cério/química , Cério/metabolismo , Elaeagnaceae/química , Peróxido de Hidrogênio/metabolismo , Tamanho da Partícula , Extratos Vegetais/química
5.
J Biotechnol ; 262: 11-27, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-28962841

RESUMO

Study on the ecological effect of metal oxide nanomaterials (NMs) has quickly amplified over the precedent years because it is assumed that these NMs will sooner or later be released into the environment. The present study deals with biologically oriented process for the green synthesis of copper oxide nanoparticles (CuO NPs) by using Morus alba leaf extract as reducing agent. Powder X-ray diffraction (XRD) and transmission electron microscope (TEM) analysis revealed the monoclinic phase and 20-40nm size respectively. The presence of reducing and capping agents revealed by Fourier transform infrared (FTIR) spectroscopy. The seedlings of Brassica oleracea var. botrytis and Solanum lycopersicum were exposed to 10, 50, 100, and 500mgL-1 concentrations of CuO NPs in the sand medium. Bioaccumulation of Cu was also investigated by atomic absorption spectroscopy (AAS). Plant exposure to 100 and 500mgL-1 of CuO NPs has resulted in significant reduction of total chlorophyll and sugar content in the two test plants while 10mgL-1 of NPs slightly increased the pigment and sugar content in tomato plants only. Augmentation of lipid peroxidation, electrolyte leakage, and antioxidant enzyme activity was observed in a dose dependent manner upon plants exposure to CuO NPs. Deposition of lignin in roots of both plants treated with the highest concentration of CuO NPs was observed. Histochemical analysis of leaves of treated plant with nitroblue tetrazolium and 3'3' diaminobenzidine showed a concentration dependent increase in superoxide and hydrogen peroxide formation in leaves. The green synthesis of CuO NPs was carried out by using Morus alba leaf extract. Accumulation of NPs more actively by tomato plants as compared to cauliflower was possibly due to the difference in root morphology. The histochemical visualization highlights the spatial organization of oxidant biochemistry occurring in response to metal stress.


Assuntos
Brassica/efeitos dos fármacos , Cobre/metabolismo , Nanopartículas Metálicas/química , Solanum lycopersicum/efeitos dos fármacos , Antioxidantes , Brassica/crescimento & desenvolvimento , Catalase/análise , Clorofila/análise , Cobre/análise , Cobre/química , Cobre/farmacologia , Eletrólitos , Química Verde/métodos , Peroxidação de Lipídeos , Solanum lycopersicum/crescimento & desenvolvimento , Microscopia Eletrônica de Transmissão , Morus/química , Nitrato Redutase/metabolismo , Fotossíntese , Extratos Vegetais/química , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Plântula , Espectroscopia de Infravermelho com Transformada de Fourier , Açúcares/análise , Superóxido Dismutase/análise , Superóxidos , Difração de Raios X
6.
J Biotechnol ; 233: 84-94, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27422354

RESUMO

In the present study, zinc oxide nanoparticles (ZnO NPs) were rapidly synthesized at room temperature by treating zinc acetate dihydrate with the flower extract of Elaeagnus angustifolia (Russian olive). The formation of ZnO NPs was primarily confirmed by UV-visible absorption spectrum in the range of 250-700nm. XRD analysis and DLS particle size analyzer revealed the size of ZnO NPs. The FTIR spectrum revealed the presence of phytochemicals in the flower extract mediated ZnO NPs. Moreover, the morphology of the ZnO NPs was determined using SEM. Seeds of Solanum lycopersicum (tomato) were separately treated with different concentrations of synthesized ZnO NPs and zinc sulphate (ZnSO4) salt suspensions (common zinc supplement). The effect of these treatments on seed germination, seedling vigor, chlorophyll, protein and sugar contents as well as on the activities of lipid peroxidation and antioxidant enzyme were studied. Leaves of plants treated with 6.1mM concentration of ZnO NPs recorded maximum reflectance while it was minimum in plants treated with 1.2mM concentration of NPs. The effect of synthesized ZnO NPs on seedling vigor, pigment, protein and sugar content was found affirmative at lower concentrations contrary to control and ZnSO4 salt. The inhibitory effect at higher concentration of NPs indicated importance in the precise application of NPs, in Zn deficient system, where plant response varies with concentration. To the best of our knowledge this is the first report on Elaeagnus angustifolia mediated synthesis of ZnO NPs and their effects on germination and physiological activity of tomato.


Assuntos
Germinação/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Solanum lycopersicum/efeitos dos fármacos , Óxido de Zinco/química , Elaeagnaceae/química , Flores/química , Química Verde , Solanum lycopersicum/metabolismo , Nanopartículas Metálicas/toxicidade , Folhas de Planta/química , Sementes/efeitos dos fármacos , Óxido de Zinco/metabolismo
7.
Biotechnol Lett ; 38(4): 545-60, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26721237

RESUMO

Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1-100 nm. A wide variety of physico-chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a "Bottom Up" approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO2, Fe3O4, TiO2, and ZnO NPs and their potential applications.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Extratos Vegetais/química , Semicondutores
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