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1.
World J Microbiol Biotechnol ; 36(2): 25, 2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-31980951

RESUMEN

In a search for novel therapeutic agents against pathogenic fungal species, Candida in addition to bacterial species, novel spinel nanoferrites were assayed against four pathogenic fungi isolated from different clinical samples of ear and skin infections: Aspergillus flavus, A. niger, A. terrus and A. fumigatus, four Candia species: Candida albicans, C. parapsilosis, C. krusei and C. tropicales, and four bacterial species: two Gram +ve: Bacillus subtilis and Streptococcus pyogenes, and two Gram -ve: Pseudomonas vulgaris and Escherichia coli. It was found that the assayed compounds displayed different levels of antifungal and antibacterial activities against all tested microorganisms. The antimicrobial potency depends on the method of synthesis of the nanoparticles and also on the microbial species.


Asunto(s)
Antibacterianos/síntesis química , Antifúngicos/síntesis química , Compuestos Férricos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Compuestos Férricos/química , Compuestos Férricos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Nanopartículas , Relación Estructura-Actividad
2.
J Photochem Photobiol B ; 202: 111723, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31785448

RESUMEN

Cadmium-Bismuth microspheres (CdS-Bi2S3) were prepared by facile solvothermal method with polyvinylpyrrolidone (PVP) employed to control the morphology of CdS-Bi2S3. The product was characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), diffuse reflectance UV-vis spectrophotometer and surface area of CdS-Bi2S3 was determined by BET analyzer. It was observed that CdS-Bi2S3 spheres exhibited good catalytic activity for the reduction of 4-nitrophenol. The photocatalytic application of CdS-Bi2S3 was evaluated for the photocatalytic degradation of environmental pollutants such as methyl orange, and methyl green under UV-visible light irradiation and it demonstrated good photocatalytic activity. Furthermore, we studied the antioxidant activity of CdS-Bi2S3 and it was observed that CdS-Bi2S3 showed antioxidant activity at all tested concentrations (5, 3 and 1 mg/mL). Antimicrobial activity of CdS-Bi2S3 microspheres was also studied for microbial control and the tested nanospheres proved to be exceptional antibacterial agent against tested Gram-positive and Gram-negative bacteria. CdS-Bi2S3 microspheres also exhibited significant cytotoxicity activity against HCT 116 (Human colon colorectal tumor) cell line. Our results indicate that CdS-Bi2S3 is good photocatalyst with several biological activities. The effective preparation method of CdS-Bi2S3 could be useful to design and fabricate the novel photocatalyst which may have several applications in the field of catalysis and in the medicine.


Asunto(s)
Antibacterianos/química , Antioxidantes/química , Luz , Microesferas , Contaminantes Químicos del Agua/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Compuestos Azo/química , Bismuto/química , Cadmio/química , Catálisis , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Células HCT116 , Humanos , Pruebas de Sensibilidad Microbiana , Nitrofenoles/química , Oxígeno Singlete/química , Contaminantes Químicos del Agua/metabolismo
3.
Chem Commun (Camb) ; 56(3): 356-359, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31825398

RESUMEN

A facile and scalable strategy for the quick library synthesis of linear-, hinged-, star-, and cyclic-polypeptides with broad-spectrum antimicrobial activity has been reported. The topologically nanoengineered polypeptides show superior antimicrobial activity against Gram-positive and Gram-negative bacteria and low toxicity, allowing screening of architectural polypeptides as mimics of host defense peptides for antimicrobials.


Asunto(s)
Antiinfecciosos/síntesis química , Péptidos/química , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Supervivencia Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Confocal , Células 3T3 NIH , Nanotecnología , Péptidos/síntesis química , Péptidos/farmacología
4.
J Photochem Photobiol B ; 202: 111706, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31775112

RESUMEN

The noble metal such as Ag and Au doped CeO2 nanoparticles was successfully prepared by ionic liquid assisted hydrothermal method in the presence of Justicia adhatoda leaves extract and were used as an antibacterial and anticancer agent. The FT-IR and Raman spectrum exhibit the peaks at 460 and 464 cm-1 assigned to CeO stretching vibrations of NPs. The electron microscopic micrographs confirmed the spherical shaped morphology of prepared NPs. The insertion of Ag and Au ions into the CeO2 surface creates lattice defects the leads to reduce the band gap energy of Ag-Au/CeO2 at 3.15 eV. The XRD results suggested the average crystalline size of the silver­gold loaded CeO2 was 28 nm. From the elemental mapping images, we have visualized that existence and uniform distribution of Ag, Au, Ce, and O in the prepared nanomaterials. The antibacterial activity of unloaded and bimetal loaded CeO2 NPs was evaluated with Gram-positive and Gram-negative bacteria using disc diffusion assay. The AgAu loaded CeO2 NPs exhibited the highest zone of inhibition against E. coli and S. aureus strains when compared with pristine CeO2, Ag loaded CeO2, and Au loaded CeO2 NPs. In addition, the 100 µg mL-1 of CeO2, Ag/CeO2, Au/CeO2 and Ag-Au/CeO2 NPs exposed the 50, 51, 52 and 56% of anticancer activity against the HeLa cells respectively. Overall, this study concludes that the ionic liquid functionalized green synthesized bimetal loaded cerium oxide NPs showed potent antibacterial and anticancer activities.


Asunto(s)
Antibacterianos/química , Antineoplásicos/química , Líquidos Iónicos/química , Justicia/química , Nanopartículas del Metal/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Cerio/química , Pruebas Antimicrobianas de Difusión por Disco , Oro/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Células HeLa , Humanos , Justicia/metabolismo , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plata/química
5.
J Photochem Photobiol B ; 202: 111652, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31760374

RESUMEN

The Biocompatibility and stability of nanoparticles using plants have been widely investigated due to its applications in the biomedical industry. Currently, there is a growing interest in nanoparticles in bone remodelling. Artemisia annua is an herbal plant commonly used in the treatment of various ailments. This study investigated the zinc oxide nanoparticles (ZnO NPs) using the green synthesis technique from A. annua and the effects of A. annua ZnO-NPs on osteoblast differentiation and inhibition of osteoclast formation. The formulated ZnO-NPs from A. annua were characterized by using various spectroscopic and microscopic methods Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Visible spectroscopy. The disc diffusion method was adopted to test the antimicrobial efficacy of ZnO-NPs. The viability of MG-63 cells were assayed by MTT test and Osteogenic-related assays like Real-time PCR and Mineralization assay were adopted to determine the effects of A. annua ZnO-NPs on the multiplication and differentiation of human osteoblast-like MG-63 cells. The characterization of A. annua ZnO-NPs revealed the crystalline nature with high zinc content and the presence of bioactive compounds from A. annua extract. The synthesized A. annua ZnO-NPs indicate significant antimicrobial potential. Besides, A. annua ZnO-NPs enhanced the proliferation, differentiation, and mineralization without causing significant cytotoxic impact on MG-63 cells. These effects indicate that A. annua ZnO-NPs can both stimulate bone formation via the differentiation of MG-63 cells. Hence, it was concluded that A. annua ZnO-NPs can be a promising agent for the treatment of bone deformities and bone-related diseases, however further research also required to explore the clear mechanism of A. annua ZnO-NPs in the formation and differentiation of MG-63 cells.


Asunto(s)
Artemisia annua/química , Diferenciación Celular , Proliferación Celular , Nanopartículas del Metal/química , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Artemisia annua/metabolismo , Calcio/metabolismo , Candida/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Humanos , Nanopartículas del Metal/toxicidad , Osteoblastos/citología , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Corteza de la Planta/química , Corteza de la Planta/metabolismo , Extractos Vegetales/química , Óxido de Zinc/química
6.
J Photochem Photobiol B ; 202: 111729, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31835161

RESUMEN

Bacterial pathogenicity is becoming a major cause of morbidity and mortality around the globe. Researchers are tirelessly finding solutions to cure or prevent infections caused by bacterial pathogens. Nanotechnology is a fast-growing area of research, effectively influencing and preventing bacterial growth. Nanoparticles (NPs) of silver, copper and gold are being used to kill bacterial pathogens in the past years but the toxicity of NPs at higher concentrations remains a major problem. Therefore, in the present study, Co3O4@ZrO2 (CoZ) core/shell NPs were synthesized using a simple sol-gel method. The synthesized NPs were characterized using different analytical techniques revealing the absorption bands at 456 and 277 nm with crystalline size of ~600 nm core/shell. The functional groups and oxidation states were characterized using FTIR analysis. Further bactericidal properties of core/shell of Co3O4@ZrO2 NPs were tested against Gram negative (Escherichia coli, Pseudomonas aeruginosa) and Gram positive (Staphylococcus aureus, Bacillus subitilis) pathogens. The core/shell CoZ NPs showed maximum growth inhibitions against S. aureus and P. aeruginosa. At the highest concentration of 200 µg/mL, the maximum zone of inhibition was observed. The synthesized CoZ NPs was also subjected to photocatalytic degradation of rhodamine B in 180 min under visible light irradiation. The present study could be an innovative and efficient research for both biomedical and wastewater treatment applications.


Asunto(s)
Nanopartículas del Metal/química , Rodaminas/química , Catálisis , Cobalto/química , Pruebas Antimicrobianas de Difusión por Disco , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Luz , Nanopartículas del Metal/toxicidad , Óxidos/química , Tamaño de la Partícula , Fotólisis/efectos de la radiación , Circonio/química
7.
J Photochem Photobiol B ; 200: 111622, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31678034

RESUMEN

Seaweeds are considered to be one of the richest bio-reserves, comprising of numerous bioactive compounds with versatile properties and multiple activities. The present study examined the antibacterial activity of two types of seaweeds, Ulva lactuca (green) and Stoechospermum marginatum (brown) collected from Oman Coastal region against five multidrug-resistant bacteria. The aqueous extracts of the seaweeds showed better antibacterial activity compared to methanol extracts. The results of the antibacterial assay revealed the excellent inhibitory effects of U.lactuca with the maximum activity against E.coli(8 mm) followed by K.pneumonia(4 mm) and S.typhi(2 mm). S.marginatum formed a clear zone of inhibition only against E.coli(3 mm).The major phytochemical constituents identified in both the types of seaweeds were Alkaloids, Terpenoids, Saponins, Flavonoids, and Steroids. Fourier transform infrared spectroscopy (FTIR) results confirmed the presence of alcoholic/phenolic groups, and amide groups in the seaweed extracts. Gas chromatography-mass spectrometry (GC-MS) results evidenced the presence of bioactive compounds such as 5-Octadecenal, 1-Tricosanol, Neophytadiene, Lactaropallidin, Phytol, Fenretinide, Lucenin, Vincadifformine in U.lactuca. Additionally, U.lactuca displayed better antioxidant activity (33.05%) in the DPPH free radical scavenging activity test compared to the S.marginatum (21.51%). Thus, the green seaweed U.lactuca could be considered as a potential source of natural antioxidant and antibacterial agents for food and pharmaceutical products.


Asunto(s)
Antibacterianos/química , Phaeophyta/química , Extractos Vegetales/química , Ulva/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/química , Bioprospección , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Phaeophyta/metabolismo , Ulva/metabolismo
8.
J Photochem Photobiol B ; 200: 111645, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31671371

RESUMEN

Antimicrobial peptide W3R6 was derived from chensinin-1b and showed potential as a novel antibiotics. However, W3R6 was susceptible to protease cleavage, which limited its therapeutic application. To improve the proteolytic resistance of W3R6, D-amino acids were incorporated into its sequence by specific amino acid substitution or whole sequence substitution according to the specificity of the cleavage site. In this study, partially substituted analog D-Arg-W3R6 and completely substituted D-enantiomer D-W3R6 were synthesized. The resistance of D-Arg-W3R6 and D-W3R6 to cleavage by the tested protease increased, particularly of D-W3R6. The antimicrobial activity of D-Arg-W3R6 was almost the same as that of the parent peptide W3R6, but the antimicrobial activity of D-W3R6 was slightly decreased. The hemolytic activity of both D-Arg-W3R6 and D-W3R6 was negligible. The CD spectrum of D-W3R6 exhibited symmetry with that of W3R6 in a membrane-mimetic environment. The membrane interaction between the D-amino acid substituted analogs and a real/mimic bacterial cell membrane was examined. The outer membrane depolarization, inner membrane permeability and dye leakage in three types of liposomes treated with D-Arg-W3R6 and D-W3R6 were not obviously different from W3R6, which could be due to the similar physical and chemical properties. In addition, these three peptides showed the binding ability with LPS micelles detected by ITC, and their ability to disrupt the LPS micelles was examined by DLS experiment and even neutralize the surface negative charge of E. coli cells. These results suggest that D-Arg-W3R6 is a promising antibiotic molecule.


Asunto(s)
Aminoácidos/química , Antiinfecciosos/química , Péptidos Catiónicos Antimicrobianos/química , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/síntesis química , Péptidos Catiónicos Antimicrobianos/farmacología , Pared Celular/química , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Liposomas/química , Liposomas/metabolismo , Péptidos/química , Permeabilidad/efectos de los fármacos , Estabilidad Proteica
9.
J Photochem Photobiol B ; 201: 111670, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31706087

RESUMEN

Synthesis of nanoparticles using plant sources as reducing agent has become important, as physical and chemical methods are costlier and affects environment. Hence it is important to develop environment friendly nanoparticle synthesis by avoiding the use of toxic chemicals. The present study aimed to synthesize silver nanoparticles (Ag Nps) and gold nanoparticles (AuNps) using Musa acuminata colla flower and its pharmaceutical activity against extended spectrum beta-lactamase (ESBL) gene producing bacteria and anticancer efficacy. The synthesized Ag and Au NPs were analysed by means of UV-Vis, FTIR, XRD,SEM and EDAX evidenced the bioreduction of Ag+ ions to Ag0 and Au3+ ions to Au0 respectively. Both nanoparticles and flower extracts were studied for antibacterial activity of ESBL gene producing bacteria by disc diffusion and microdilution (Resazurin) method. In vitro anticancer efficacy (MCF-7) and toxicity (VERO) of AgNPs, AuNPs, aqueous extract and ethanol extract of flowers were performed by MTT assay. IC50 value for DPPH analysis was at 390 µg and 460 µg for ethanol and aqueous extract respectively. Total antioxidant content was found be 740 µg/mg and 460 µg/mg for ethanol and aqueous extract. GCMS analysis authenticated the existence of the compounds namely, 9,12-octadecadienoic acid(z,z)- and n-hexadecanoic acid in the crude extract of the samples. Among the samples, AgNPs had best antibacterial activity. AgNPs and AuNPs were confirmed by colour change to reddish brown and ruby red. Further ƛmax were obtained at 474 and 540 nm by UV - visible spectrum. SEM analysis revealed the particle size ranges from 12.6 to 15.7 nm for silver and 10.1 to 15.6 nm for gold nanoparticles. The EDAX spectrum shows a strong signal for elemental Ag and Au at ~ 3 keV and 1.5 keV. The XRD patterns for silver and gold nanoparticles at 36.701, 42.900, 63.281 and 76.398 corresponding to the lattice planes 2.4467, 2.1064, 1.46839, 1.24564 nm and 27.32, 36.7228, 39.56, 42.888, 63.253, 63.253, 65.02 and 76.383 corresponding to the lattice planes 3.262, 2.44530, 2.276, 2.1070, 1.46897, 1.4332 and 1.24585 nm. The IC50 values for MCF-7 and VERO cells were 30.0 µg/ml and 55.0 µg/ml respectively.


Asunto(s)
Antibacterianos/química , Antineoplásicos/química , Oro/química , Musa/química , Plata/química , Animales , Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Flores/química , Flores/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Humanos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Musa/metabolismo , Extractos Vegetales/química , Células Vero
10.
J Photochem Photobiol B ; 201: 111649, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31710925

RESUMEN

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.


Asunto(s)
Alpinia/química , Antiinfecciosos/síntesis química , Nanopartículas del Metal/química , Plata/química , Alpinia/metabolismo , Antiinfecciosos/farmacología , Compuestos Azo/química , Catálisis , Colorantes/química , Frutas/química , Frutas/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Tecnología Química Verde , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Extractos Vegetales/química , Luz Solar
11.
J Photochem Photobiol B ; 201: 111683, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31710928

RESUMEN

In recent years dendrimers have fascinated the investigators towards targeted drug delivery because of their versatile framework and exhibit immense potentiality in entrapping drug moieties through host-guest interactions and serve as a promising vector in biological applications. The current investigation is focused on developing pegylated citric acid cefotaxime dendrimers through the divergent method and its characterization through spectroscopic, microscopic, thermal and microscopic techniques. Among the spectroscopic techniques, 1H NMR and 13C NMR elucidated the key functional groups at various chemical shifts while ESI-MS pointed out the molecular weight of cefotaxime sodium in various generations. Similarly, FTIR, DSC, and AFM investigations detailed that the generations are devoid of incompatibilities, structural deformities and can be opted for targeted drug delivery. The drug entrapment studies and in-vitro drug release studies highlight CFTX G5 containing 92.4% entrapment efficacy and 83.8% drug release in 48 h and specifies a sustain release characteristics. In connection to the above, the in-vivo studies reveal a potent antibacterial activity against various gram-positive and gram-negative microorganisms with a decreased hemolysis and cytotoxicity effects and reflect a high margin of safety regarding pegylated CFTX dendrimers. Further, the antibacterial activities are supported through confocal microscopy that clarified the cellular uptake of dendritic molecules and their internalization.


Asunto(s)
Cefotaxima/química , Ácido Cítrico/química , Dendrímeros/química , Nanoestructuras/química , Células A549 , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacología , Cefotaxima/metabolismo , Cefotaxima/farmacología , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Liberación de Fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Semivida , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nanoestructuras/toxicidad , Polietilenglicoles/química
12.
BMC Complement Altern Med ; 19(1): 279, 2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31640666

RESUMEN

BACKGROUND: Rapid emergence of multidrug resistant (MDR) organisms in hospital and community settings often result into treatment failure, thus leading the clinicians with fewer treatment options. Cyathea gigantea, an ethnomedicinally important fern used in cuts and wound infections. So, if this medicinal plant is used in treating the MDR infections then it might bring certain relief in future treatment options. METHODS: Antibacterial activity of C. gigantea against MDR bacteria was assed using well diffusion and broth microdilution methods to determine the diameters of growth inhibition zones, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Synergistic activity was also determined with the conventional antibiotics by disc diffusion method followed by FIC index of each of the tested antibiotic was calculated. The active extract was then subjected to fractionation by column chromatography and antibacterial activity was done with each of the collected fractions. RESULTS: Crude extract of C. gigantea was found to be active against all the tested organisms. The MIC was 200 µg/ml against Gram-positive i.e., Staphylococcus aureus ATCC 25923 and 400 µg/ml against Gram-negative i.e., Escherichia coli ATCC 25922 and Pseudomonas aeruginosa PAO1, while the MBC was 400 µg/ml in case of Gram-positive and 800 µg/ml for Gram-negative. The synergistic activity revealed that the plant extract increased the antibacterial property of the studied antibiotics and the FIC index showed that significant synergistic activity was shown by ciprofloxacin followed by tetracycline, ampicillin and oxacillin. Antibacterial activity with the fractionated extract showed that the FR II, FR III and FR IV were active against both Gram-positive and Gram-negative bacteria, whereas FR I, FR V and FR VI did not show antibacterial property against any of the tested bacteria. CONCLUSIONS: Extracts of C. gigantea was found active against both selected Gram-positive and Gram-negative organisms and thus offers the scientific basis for the traditional use of the fern. The present study also provides the basis for future study to validate the possible use against multidrug resistant organisms.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Extractos Vegetales/farmacología , Tracheophyta/química , Antibacterianos/química , Infecciones Bacterianas/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Hojas de la Planta/química , Plantas Medicinales/química
13.
Chem Biodivers ; 16(12): e1900373, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31654549

RESUMEN

Phytochemicals, which are commonly found at different levels in many medicinal plants, are natural strong antioxidants used in traditional medicine. In this research, determination of differences of phytochemical compositions and biological properties were aimed as periodically (pre-, full and post flowering) and daily (6 am, 1 pm and 8 pm) in Achillea gypsicola Hub.-Mor. The volatile oils belonging to A. gypsicola were obtained by hydrodistillation and analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC/MS). The antimicrobial activities of the volatile oils were determined with disc diffusion method. The microdilution method was used to determine minimum inhibitory concentration (MIC). Total phenolic and flavonoid contents were determined by spectrophotometric methods and antioxidant capacities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, reducing power (RP) and metal chelating activity (MCA) assay. In addition, the phenolic acid and flavonoid compositions were evaluated by reversed phase-high-performance liquid chromatography (RP-HPLC). This study presented a comprehensive report for the first time on evaluation of the phytochemical composition and the biological properties of A. gypsicola at different phenological stages. Thirty-two compounds, containing the major component as camphor, 1,8-cineole and borneol, were detected. Designated harvest time for the highest yield of volatile oils was found to be at full flowering stage-1 pm. It has been observed that the volatile oil composition changes periodically and even daily. Also, in this research, menthol and menthone were found as the composition of volatile oil in Achillea species for the first time. Full flowering stage was found as the richest period in terms of phenolic acid and flavonoid compositions of A. gypsicola for the first time. The species examined in this research showed a high antioxidant and antimicrobial activity in comparison to other studies with Achillea species. The volatile oils exhibited high performances with range of inhibition zones (8.3-42.3 mm) and minimum inhibitory concentration values (2.25-144 µg/ml). Besides, a high correlation between antioxidant activity and phenolic content of A. gypsicola was found. These results suggest that A. gypsicola can be used as a safe source in the cosmetic, food and pharmaceutical industries.


Asunto(s)
Achillea/química , Aceites Volátiles/química , Fitoquímicos/química , Achillea/metabolismo , Antioxidantes/química , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Flavonoides/análisis , Flavonoides/química , Flavonoides/farmacología , Flores/química , Flores/metabolismo , Hongos/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Fenoles/análisis , Fenoles/química , Fenoles/farmacología , Fitoquímicos/farmacología , Análisis de Componente Principal
14.
Chem Biodivers ; 16(12): e1900461, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31557406

RESUMEN

The discovery of new antimicrobial agents is extremely needed to overcome multidrug-resistant bacterial and tuberculosis infections. In the present study, eight novel substituted urea derivatives (10a-10h) containing disulfide bond were designed, synthesized and screened for their in vitro antimicrobial activities on standard strains of Gram-positive and Gram-negative bacteria as well as on Mycobacterium tuberculosis. According to the obtained results, antibacterial effects of the compounds were found to be considerably better than their antimycobacterial activities along with their weak cytotoxic effects. Molecular docking studies were performed to gain insights into the antibacterial activity mechanism of the synthesized compounds. The interactions and the orientation of compound 10a (1,1'-((disulfanediylbis(methylene))bis(2,1-phenylene))bis(3-phenylurea)) were found to be highly similar to the original ligand within the binding pocket E. faecalis ß-ketoacyl acyl carrier protein synthase III (FabH). Finally, a theoretical study was established to predict the physicochemical properties of the compounds.


Asunto(s)
Antibacterianos/síntesis química , Disulfuros/química , Urea/análogos & derivados , 3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/química , 3-Oxoacil-(Proteína Transportadora de Acil) Sintasa/metabolismo , Animales , Antibacterianos/farmacología , Antituberculosos/síntesis química , Antituberculosos/farmacología , Sitios de Unión , Supervivencia Celular/efectos de los fármacos , Enterococcus faecalis/enzimología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Estructura Terciaria de Proteína , Células RAW 264.7 , Relación Estructura-Actividad , Urea/farmacología
15.
Eur J Med Chem ; 183: 111671, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31536892

RESUMEN

The rapid emergence and spread of multi-resistant bacteria have created an urgent need for new antimicrobial agents. We report here a series of amphipathic α,α-disubstituted ß-amino amide derivatives with activity against 30 multi-resistant clinical isolates of Gram-positive and Gram-negative bacteria, including isolates with extended spectrum ß-lactamase - carbapenemase (ESBL-CARBA) production. A variety of halogenated aromatic side-chains were investigated to improve antimicrobial potency and minimize formation of Phase I metabolites. Net positive charge and cationic character of the derivatives had an important effect on toxicity against human cell lines. The most potent and selective derivative was the diguanidine derivative 4e with 3,5-di-brominated benzylic side-chains. Derivative 4e displayed minimum inhibitory concentrations (MIC) of 0.25-8 µg/mL against Gram-positive and Gram-negative reference strains, and 2-32 µg/mL against multi-resistant clinical isolates. Derivative 4e showed also low toxicity against human red blood cells (EC50 > 200 µg/mL), human hepatocyte carcinoma cells (HepG2: EC50 > 64 µg/mL), and human lung fibroblast cells (MRC-5: EC50 > 64 µg/mL). The broad-spectrum antimicrobial activity and low toxicity of diguanylated derivatives such as 4e make them attractive as lead compounds for development of novel antimicrobial drugs.


Asunto(s)
Amidas/química , Antiinfecciosos/química , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Amidas/síntesis química , Amidas/farmacología , Animales , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Halogenación , Humanos , Ratones , Pruebas de Sensibilidad Microbiana
16.
Chem Biodivers ; 16(12): e1900289, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31552700

RESUMEN

Achillea species and in particular Achillea tenuifolia Lam. is generally used as a food flavor and traditional remedies, especially in the initial developmental stage for medical conditions in the Mediterranean part of Iran. In this report, we extracted the essential oil from the aerial parts of A. tenuifolia (collected from Khoy), at various developmental stages (i. e., vegetative, flowering and fruiting), characterized them and studied their antibacterial activities. Of 46, 51 and 38 components found in the vegetative, flowering, and fruiting stages, respectively, 35 were present in all three stages, including oxygenated terpenes such as carvacrol (30.85-34.11), germacrene C (16.21-17.87), spathulenol (7.26-8.96), ß-sesquiphellandrene (4.11-4.25), τ-muurolol (2.27-3.25) and α-cadinol (2.01-3.29). We witnessed that the composition of the essential oils varies with phenological stages and geographic regions. The essential oil demonstrated substantial antibacterial properties against both Gram-positive and Gram-negative bacteria, indicated by disk method, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. Except Pseudomonas aeruginosa, the essential oils of various phenological stages showed higher antibacterial activity against tested bacteria, with Bacillus anthracis as the most sensitive strain. Moreover, although antibacterial characteristics of the essential oil from the vegetative and flowering stages were similar (p=0.91), they were significantly different from those of fruiting stage (p<0.005 in both MIC and MBC tests). This emphasizes the importance of the developmental stage of the plant in the biological properties of its essential oil and justifies the widespread application of this plant in the vegetative stage.


Asunto(s)
Achillea/química , Antibacterianos/química , Aceites Volátiles/química , Achillea/metabolismo , Antibacterianos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Desarrollo de la Planta , Terpenos/química
17.
Mater Sci Eng C Mater Biol Appl ; 104: 109968, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31500003

RESUMEN

This is a report on the antibacterial activity of ZnO and CuO nanoparticles synthesized via sol-gel method. The studies were performed on Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli and Pseudomonas aeruginosa bacteria using disc and well diffusion methods, bioluminescence and optical density analysis. The results show a strong decline of bacterial strains after a short contact with nanoparticles. The modelling allowed clarifying the bacterial sensitivity of toxic agents at different stages of their population evolution kinetics. It was concluded that the bacterial suppression is most effective at the exponential growth phase while it is of a lower effectiveness at the lag and stationary phases. The CuO and ZnO nanoparticles showed comparable effectiveness at the exponential growth phase. In the same time, ZnO was almost inactive at the lag phase and of lower effectiveness at the stationary phase, at which CuO conserved a significant activity.


Asunto(s)
Antibacterianos/farmacología , Cobre/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Nanopartículas del Metal/química , Óxido de Zinc/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Tamaño de la Partícula
18.
Molecules ; 24(18)2019 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-31500359

RESUMEN

Lavender oil is one of the most valuable aromatherapy oils, its anti-bacterial and anti-fungal activities can be explained by main components such as linalool, linalyl acetate, lavandulol, geraniol, or eucalyptol. The aim of the study was to assess the anti-microbial effects of two different lavender oils on a mixed microbiota from facial skin. The commercial lavender oil and essential lavender oil from the Crimean Peninsula, whose chemical composition and activity are yet to be published, were used. Both oils were analysed by gas chromatography coupled to mass spectrometry. The composition and properties of studied oils were significantly different. The commercial ETJA lavender oil contained 10% more linalool and linalyl acetate than the Crimean lavender oil. Both oils also had different effects on the mixed facial skin microbiota. The Gram-positive bacilli were more sensitive to ETJA lavender oil, and Gram-negative bacilli were more sensitive to Crimean lavender oil. However, neither of the tested oils inhibited the growth of Gram-positive cocci. The tested lavender oils decreased the cell number of the mixed microbiota from facial skin, but ETJA oil showed higher efficiency, probably because it contains higher concentrations of monoterpenoids and monoterpenes than Crimean lavender oil does.


Asunto(s)
Antibacterianos/farmacología , Monoterpenos/farmacología , Aceites Volátiles/farmacología , Aceites Vegetales/farmacología , Piel/microbiología , /análisis , Antibacterianos/química , Cara , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Lavandula/química , Pruebas de Sensibilidad Microbiana , Monoterpenos/análisis , Monoterpenos/química , Aceites Volátiles/química , Aceites Vegetales/química
19.
Nat Commun ; 10(1): 4057, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31492849

RESUMEN

Simultaneous imaging and treatment of infections remains a major challenge, with most current approaches being effective against only one specific group of bacteria or not being useful for diagnosis. Here we develop multifunctional nanoagents that can potentially be used for imaging and treatment of infections caused by diverse bacterial pathogens. The nanoagents are made of fluorescent silicon nanoparticles (SiNPs) functionalized with a glucose polymer (e.g., poly[4-O-(α-D-glucopyranosyl)-D-glucopyranose]) and loaded with chlorin e6 (Ce6). They are rapidly internalized into Gram-negative and Gram-positive bacteria by a mechanism dependent on an ATP-binding cassette (ABC) transporter pathway. The nanoagents can be used for imaging bacteria by tracking the green fluorescence of SiNPs and the red fluorescence of Ce6, allowing in vivo detection of as few as 105 colony-forming units. The nanoagents exhibit in vivo photodynamic antibacterial efficiencies of 98% against Staphylococcus aureus and 96% against Pseudomonas aeruginosa under 660 nm irradiation.


Asunto(s)
Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Fotoquimioterapia/métodos , Antibacterianos/química , Antibacterianos/farmacocinética , Infecciones Bacterianas/microbiología , Disacáridos/química , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/fisiología , Humanos , Nanopartículas/química , Porfirinas/química , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Fármacos Sensibilizantes a Radiaciones/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología
20.
Comput Biol Chem ; 83: 107114, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31493741

RESUMEN

Pittosporum senacia (PS) Putt. (Pittosporaceae), indigenous to the Mascarene Islands, is a common ingredient in traditional medicines. However, there is currently a dearth of studies to validate some of these traditional claims. Given the broad traditional uses of PS against several diseases, we aimed to provide a comprehensive insight into the biological and chemical profile of P. senacia. The antioxidant, enzyme inhibitory activity, anticancer, and phytochemical composition of the methanolic extract of P. senacia leaf extracts were studied. The possible interaction and binding mode of the most abundant phytochemicals were studied via in silico docking experiments on tyrosinase and α-glucosidase. The mechanism behind the cytotoxic property of P. senacia extract for MDA-MB-231 was also examined using different methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability test checking apoptosis-associated genes, and wound healing assays. Twenty-six compounds were identified, of which caffeoylquinic acid derivatives, ferulic acid derivative, cinnamoylquinic acid derivative and two other polyphenols (oleuropeine and isoramnetin glucoside) being abundant, have been tested using in silico studies, against α-glucosidase and tyrosinase. The extract (IC50 = 118.8 µg/ml) exhibited time and dose dependent anti-proliferative effect on human breast cancer cell line, MDA-MB-231. According to the expression profile of apoptosis inhibitors and apoptosis promoters genes, expression of Bax and Bak genes were significantly increased compared to Bcl-2 and Birc5 genes. Based on wound healing analysis, cell migration was inhibited after the application of the plant extract. The present findings suggested that PS might be a good candidate as sources of bioactive compounds for designing functional applications.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , ADN/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Simulación del Acoplamiento Molecular , Extractos Vegetales/farmacología , Rosales/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plásmidos/efectos de los fármacos , Espectrometría de Masa por Ionización de Electrospray , Células Tumorales Cultivadas , alfa-Glucosidasas/metabolismo
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