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1.
Carbohydr Polym ; 330: 121786, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368093

RESUMO

Copper bionanocomposites (CBNCS) were synthesized using Ipomoea carnea- sourced nanocellulose as support via an eco-friendly and cost-effective method. X-ray Diffractometer (XRD) pattern of CBNCS confirmed the octahedral structure of Cu2O, the face-centered cubic (FCC) crystal structure of Cu(0). XRD also revealed the crystal lattice of cellulose II. Surface Electron Microscope (SEM) and Transmission Electron Microscope (TEM) revealed the uniform distribution of copper nanoparticles (Cu NPs) with an average size of 10 nm due to the presence of nanocellulose. X-ray photoelectron spectroscopy (XPS) provided information about the electronic, chemical state and elemental composition of CBNCS. Thermogravimetric Analysis (TGA) showed the thermal stability of CBNCS. CBNCS catalyzed the rearrangement of oximes to primary amides in a very mild condition with a high yield of up to 92 %. CBNCS effectively inhibited the growth of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with lower minimum inhibitory concentration MIC values. Antioxidant activity and electrical conductivity of CBNCS were also determined.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Antibacterianos/química , Cobre/química , Staphylococcus aureus , Nanopartículas Metálicas/química , Escherichia coli , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Ethnopharmacol ; 282: 114600, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34487845

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Cleome species in particular (C. gynandra Linn, C. viscosa Linn, C. rutidosperma DC, C. felina Linn.), commonly known as spider flowers, belong to the genus of flowering plants in Cleomaceae family. Found primarily in the African countries (Kenya, Tanzania, Egypt, South Africa, and Nigeria), Asian countries (India and Afghanistan), European countries (Italy), and also in other countries like Brazil and Austria. These plants are commonly cultivated as a vegetable crop for their nutritional benefits, and the leaves are widely consumed for their health-promoting effects. The different parts of the plants, such as leaves, seeds, flowers, and roots, are used to treat acute and chronic inflammatory disorders, hepatotoxicity, malaria, fungal diseases, and cancer. AIM OF THE STUDY: Detailed investigations in underlining the molecular mechanisms and their wide variety of effects in treating various diseases remain ambiguous. The review focuses on an in-depth discussion of studies targeting phytochemistry and polypharmacology. Thus, the review aims to recapitulate the therapeutic potential of the components of Cleome involved in the treatment of a wide variety of ailments from ancient times were collected and presented along with strategies aiming for future studies. MATERIALS AND METHODS: The information provided is collected from several scientific databases (PubMed, Elsevier, ScienceDirect) and traditional medicine books, and other professional websites. RESULTS AND CONCLUSION: Investigations and current evidence revealed that the different chemical constituents present in cleome species possess various health-promoting effects along with the aerial parts showing promising traditional uses in traditional healing and culinary. An explorative survey in the current review highlights the traditional healing effects along with a broad scope of studies that can be performed in the future.


Assuntos
Cleome , Etnofarmacologia , Etnofarmacologia/métodos , Etnofarmacologia/tendências , Alimento Funcional , Humanos , Medicina Tradicional/métodos , Medicina Tradicional/tendências , Fitoterapia/métodos , Plantas Medicinais
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119459, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497974

RESUMO

An environment-friendly and economically sound method was developed to achieve a multi-functional ZnO nanoparticles (ZnO NPs) using water extract of Livistona jekinsiana. The ZnO NPs absorbed maximum wavelength of light at 332 nm in UV-Visible spectroscopy (UV/Vis). X-Ray Diffraction (XRD) pattern revealed the crystallinity of the nanoparticles with the crystallite size around 22.45 nm. The geometry, shape, size, and elemental composition were determined by Transmission Electron Microscope (TEM) and Energy Dispersive Spectroscopy (EDS). The presence of phytochemicals and the typical zinc-oxygen group in the ZnO NPs was implied by Fourier Transform Infrared spectroscopy (FTIR). Photo luminescence spectroscopy (PL), and Dynamic Light Scattering (DLS) techniques were also used to characterize and study the different features of ZnO NPs. The multifunctional ZnO NPs showed an efficient photodegradative effect towards the degradation of two anthropogenic dyes, methyl orange (MO) and methylene blue (MB) under solar radiation. The degradation reaction of MO and MB was compliantwithzero-order kinetics and first-order kinetics respectively. Also, Livistona jekinsiana fabricated ZnO NPs showed potential Antibacterial activity against S. aureus, B. subtilis, E. coli and K. pneumonia bacteria and effective antioxidant activity using DPPH scavenging assay. The mechanism of the antibacterial activity was established by estimating the ROS generation and percentage of DNA in K. pneumonia cell. The study illustrated the reducing and stabilizing property of the Livistona jekinsiana extract as a novel source and potential photodegradative and therapeutic effects of the ZnO NPs.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Antibacterianos/farmacologia , Bactérias , Escherichia coli , Humanos , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus , Difração de Raios X
4.
Nat Prod Res ; 35(3): 517-520, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31373228

RESUMO

The genus Elaeocarpus belongs to the Elaeocarpaceae family, consists of about 350 species distributed in the tropical and subtropical regions. Plants in the genus, reportedly, contain compounds known for various biological activities like affinity for the δ-opioid receptor, antioxidant, cytotoxicity and antimicrobial activities. Elaeocarpus floribundus, commonly known in India as 'Indian Olive' is a medicinal plant widely distributed through Eastern Asia and the pacific. Here, we report the isolation and spectroscopic characterization of fifteen compounds (1-15) and additional three compounds (16-18) were obtained as mixtures. This includes four fatty acids, three diterpenoids, one triterpene alcohol, two fatty alcohols, three phaeophytins, one phytosterol, one sesquiterpene, and three hydrocarbons from the hexane extract of the leaves. Compounds 1-18 are reported for the first time from this source. To the best of our knowledge, this is an initial report of the isolation of compounds 1-11, and 14-18 from the genus Elaeocarpus.


Assuntos
Elaeocarpaceae/química , Compostos Fitoquímicos/análise , Folhas de Planta/química , Diterpenos/análise , Índia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fitosteróis/análise , Extratos Vegetais/química , Plantas Medicinais/química , Triterpenos/análise
5.
Carbohydr Polym ; 206: 863-872, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30553395

RESUMO

Cellulose extracted from the rhizomes of Alpinia nigra was utilized in the synthesis of cellulose acetate. Furthermore, the cellulose acetate reacted with organophillic montmorillonite to form a composite. All the products including cellulose, cellulose acetate and the composite were characterized with the help of standard analytical techniques. The synthesised composite was effectively used as an adsorbent for the toxic dye Eosin Y which is a common waste water effluent. The influence of different parameters such as contact time, temperature and effect of initial concentration of dye on the adsorption process was investigated. Moreover the cellulose acetate-montmorillonite composite was biodegradable which was confirmed from a compost test conducted for a period of six months. These results clearly indicate that cellulose acetate-montmorillonite composite is an interesting alternative for the treatment of waste water effluents.

6.
J Photochem Photobiol B ; 201: 111649, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710925

RESUMO

In the present systematic study, silver nanoparticles have been synthesized using the fruits of Alpinia nigra. Apart from the presence of saponins, glycosides, alkaloids, steroids, the extract of A. nigra fruits are rich in polyphenols. The Total Flavonoid and Phenol Content of A. nigra fruits extract is 718 mgRE/g extract and 74.9 mgGAE/g extract respectively. The formation of the nanoparticles was validated through characterization techniques like UV-Vis spectroscopy, X- ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Energy dispersive X-ray spectroscopy (EDX). The spherical shape of silver nanoparticles is observed in Transmission Electron Microscopy (TEM) images. The average particle size of the silver nanoparticles is 6 nm. The biomolecules of the fruit extract played the dual role of reducing and capping agents which is evident from Fourier Transform Infrared (FTIR) spectrometer and Scanning Electron Microscopy (SEM) image analysis. The A. nigra capped silver nanoparticles exhibited promising antimicrobial activity against gram negative bacteria Klebsiella pneumoniae, gram positive bacteria Staphylococcus aureus and the pathogenic fungus, Candida albicans. Amongst the three pathogens, Klebsiella pneumoniae is the most susceptible to silver nanoparticles. Furthermore, the nanoparticles efficiently catalysed the degradation of the anthropogenic dyes Methyl orange, Rhodamine B and Orange G in the presence of sunlight. The photocatalytic degradation process follows the pseudo-first order kinetics. These results confirm that the silver nanoparticles can be efficiently synthesized via a green route using A. nigra fruits with applications as antimicrobial and catalytic agents.


Assuntos
Alpinia/química , Anti-Infecciosos/síntese química , Nanopartículas Metálicas/química , Prata/química , Alpinia/metabolismo , Anti-Infecciosos/farmacologia , Compostos Azo/química , Catálise , Corantes/química , Frutas/química , Frutas/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Extratos Vegetais/química , Luz Solar
7.
Carbohydr Polym ; 195: 189-198, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29804968

RESUMO

Highly efficient copper nanoparticles supported over nanocellulose have been prepared by a simple chemical reduction method. The cellulose was extracted from the inner stem of Hibiscus sabdariffa and used as a polymer matrix for the synthesis of copper nanoparticles. The formation of the nanoparticles was validated through different characterization techniques like X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR), UV-vis spectroscopy (UV) and Energy dispersive X-Ray Spectroscopy (EDX). Moreover the morphology of the cellulose supported copper nanoparticles was investigated using field emission scanning electron microscope (FESEM) and field emission transmission electron micrograph (FETEM) which revealed the formation of spherical nanoparticles with an average size of 7 nm. The synthesized catalyst was then utilized effectively in the CN coupling reactions involving open chained as well as cyclic secondary amines and electron deficient vinylic compounds. The catalyst demonstrated excellent yield (82%-95%) and was easily recycled for upto six cycles without any significant loss of catalytic activity.

8.
J Photochem Photobiol B ; 186: 51-58, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30015060

RESUMO

Plants and their extracts play an important role in the green synthesis of nanoparticles mainly because of their environmental benignity. Based on plant extracts number of metal nanoparticles have been synthesized. In our study, we report a green technique for the synthesis of gold nanoparticles using the aqueous extracts of Alpinia nigra leaves and their photocatalytic activities. The antioxidant, antibacterial and antifungal potential of the synthesized nanoparticles were also evaluated. The aqueous extract of the plant is rich in flavonoids with Total Flavonoid Content of 491mgRE/g extract. The presence of flavonoids was further confirmed through analytical High Performance Liquid Chromatography (HPLC) analysis. The A. nigra mediated syntheses of gold nanoparticles (ANL-AuNPs) were characterized by UV-Vis spectrophotometer, Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The crystalline nature of the ANL-AuNPs was confirmed by the powder XRD analysis. The TEM micrographs showed that the ANL-AuNPs was predominantly spherical in shape and the average particle size was 21.52 nm. The polyphenolics and other functional groups present in the aqueous extract that acted as reducing and capping agent in the synthesis of the Au-NPs were identified via FTIR spectral analysis. These green synthesized nanoparticles exhibited antioxidant activity with IC50 value of 52.16 µg/ml and showed inhibition in the growth of both gram-positive and gram-negative bacteria. The pathogenic fungus, Candida albicans was also susceptible to these nanoparticles. The ANL-AuNPs in the presence of sunlight catalyzed the degradation of the anthropogenic pollutant dyes, Methyl Orange and Rhodamine B with percent degradation of 83.25% and 87.64% respectively. The photodegradation process followed pseudo first order kinetic model. These results confirm that Alpinia nigra is a potential bioresource for the synthesis of Au-NPs with versatile applications.


Assuntos
Compostos Azo/química , Ouro/química , Luz , Nanopartículas Metálicas/química , Rodaminas/química , Alpinia/química , Alpinia/metabolismo , Antioxidantes/química , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Catálise , Escherichia coli/efeitos dos fármacos , Flavonoides/química , Química Verde , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fotólise/efeitos da radiação , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Polifenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Steroids ; 70(8): 494-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15894032

RESUMO

Regioselective synthesis of novel steroidal anti-inflammatory ante drug analogues, viz., [16alpha,17alpha-d]-isoxazolines 1(a-h) and 2(a-h) prepared in a single step in good yield by the reaction of 16-dehydropregnenolone acetate (16-DPA) 1 or related 21-chloro-20-oxopregnane 2 with various aldoximes (a-h) in presence of chloramine-T in refluxing ethanol.


Assuntos
Anti-Inflamatórios/síntese química , Isoxazóis/síntese química , Esteroides/síntese química , Anti-Inflamatórios/química , Cloraminas/química , Etanol/química , Compostos Heterocíclicos/química , Isoxazóis/química , Espectrometria de Massas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oximas/química , Pregnanos/química , Pregnenolona/análogos & derivados , Pregnenolona/química , Esteroides/química , Relação Estrutura-Atividade , Compostos de Tosil/química
10.
Steroids ; 76(5): 497-501, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21277882

RESUMO

A facile synthesis of the side chain of loteprednol etabonate, namely, chloromethyl-17α-[(ethoxycarbonyl))oxy]-11ß-hydro of loteprednol etabonate, viz., chloromethyl-17α-[(ethoxycarbonyl))oxy]-11xy-3-oxoandrosta-1,4-diene-17ß-carboxylate--an ocular soft corticosteroid, has been described starting from a 20-oxopregnane, namely, 3ß-acetoxy-pregn-5(6),16(17)-diene-20-one (16-dehydropregnenolone acetate, i.e., 16-DPA) using our recently developed metal-mediated halogenation as a key reaction.


Assuntos
Androstadienos/síntese química , Pregnanos/química , Corticosteroides , Antialérgicos , Halogenação , Etabonato de Loteprednol , Metais , Dispositivos Ópticos
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