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1.
Polymers (Basel) ; 8(6)2016 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-30979315

RESUMEN

This study describes the preparation of nanoprotein particles having lignin peroxidase (LiP) using a photosensitive microemulsion polymerization technique. The protein-based nano block polymer was synthesized by cross-linking of ligninase enzyme with ruthenium-based aminoacid monomers. This type polymerization process brought stability in different reaction conditions, reusability and functionality to the protein-based nano block polymer system when compared the traditional methods. After characterization of the prepared LiP copolymer nanoparticles, enzymatic activity studies of the nanoenzymes were carried out using tetramethylbenzidine (TMB) as the substrate. The parameters such as pH, temperature and initial enzyme concentration that affect the activity, were investigated by using prepared nanoLip particles and compared to free LiP. The reusability of the nano-LiP particles was also investigated and the obtained results showed that the nano-LiP particles exhibited admirable potential as a reusable catalyst.

2.
Phytother Res ; 30(1): 9-15, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26463741

RESUMEN

Vulpinic and gyrophoric acids are known as ultraviolet filters for natural lichen populations because of their chemical structures. However, to the best of our knowledge, there has been no reference to their cosmetic potential for skin protection against ultraviolet B (UVB)-induced damage and, consequently, we propose to highlight their photoprotective profiles in human keratinocytes (HaCaT). Therefore, vulpinic acid and gyrophoric acid were isolated from acetone extracts of Letharia vulpina and Xanthoparmelia pokornyi, respectively. Their photoprotective activities on irradiated HaCaT cells and destructive effects on non-irradiated HaCaT cells were compared through in vitro experimentation: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays, 4',6-diamino-2-phenylindole and tetramethylrhodamine B isothiocyanate-phalloidin staining protocols. Both of the lichen substances effectively prevented cytotoxic, apoptotic and cytoskeleton alterative activities of 2.5 J/cm(2) UVB in a dose-dependent manner. Moreover, vulpinic and gyrophoric acids showed no toxic, apoptotic or cytoskeleton alterative effects on non-irradiated HaCaT cells, except at high doses (≥400 µM) of gyrophoric acid. The findings suggest that vulpinic and gyrophoric acids can be promising cosmetic ingredients to photo-protect human skin cells and should therefore be further investigated by in vitro and in vivo multiple bioassays.


Asunto(s)
Benzoatos/farmacología , Furanos/farmacología , Queratinocitos/efectos de los fármacos , Fenilacetatos/farmacología , Protectores contra Radiación/farmacología , Rayos Ultravioleta/efectos adversos , Línea Celular , Supervivencia Celular , Humanos , Queratinocitos/efectos de la radiación , Líquenes/química , Piel/efectos de los fármacos
3.
Water Sci Technol ; 68(7): 1550-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24135104

RESUMEN

This study reports kinetics and equilibrium of lead sorption onto the biomass of Enterococcus faecium. E. faecium is a lactic acid bacterium and was isolated from meat. Batch experiments were carried out to analyze the effects of the initial lead concentration, initial pH of the medium, agitation time and temperature on the biosorption. The lead sorption was found to increase with the increase in the solution pH, reaching a plateau value beyond pH 5, and the most favorable pH for removal was determined as 5.0. The highest lead uptake capacity of the biomass was obtained at the initial lead concentration of 300 mg L(-1). The Langmuir and Freundlich adsorption models were applied to determine the biosorption isotherm, and the equilibrium data correlated well with the Langmuir model. The pseudo-second-order kinetic model was more suitable to fit the experimental data. The results were promising that the biomass of this lactic acid bacterium can be successfully used as a convenient adsorbent for lead removal from aqueous solutions.


Asunto(s)
Biomasa , Enterococcus faecium/química , Plomo/química , Contaminantes Químicos del Agua/química , Agua/química , Adsorción , Cinética , Factores de Tiempo , Purificación del Agua/métodos
4.
ScientificWorldJournal ; 2013: 146092, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23853528

RESUMEN

The removal of lead (II) ions from aqueous solutions was carried out using an activated carbon prepared from a waste biomass. The effects of various parameters such as pH, contact time, initial concentration of lead (II) ions, and temperature on the adsorption process were investigated. Energy Dispersive X-Ray Spectroscopy (EDS) analysis after adsorption reveals the accumulation of lead (II) ions onto activated carbon. The Langmuir and Freundlich isotherm models were applied to analyze equilibrium data. The maximum monolayer adsorption capacity of activated carbon was found to be 476.2 mg g⁻¹. The kinetic data were evaluated and the pseudo-second-order equation provided the best correlation. Thermodynamic parameters suggest that the adsorption process is endothermic and spontaneous.


Asunto(s)
Carbón Orgánico/química , Residuos Industriales/prevención & control , Plomo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Agua/química , Absorción , Iones/química , Iones/aislamiento & purificación , Plomo/química , Glycine max , Ultrafiltración/métodos , Contaminantes Químicos del Agua/química
5.
Phytother Res ; 24(5): 754-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19943241

RESUMEN

Lichens have been used in folk medicine for centuries and are symbiotic organisms of fungi and algae that produce unique secondary metabolites. Olivetoric acid is one of these secondary metabolites. In the present study, the effect of olivetoric acid isolated from acetone extract of the lichen Pseudevernia furfuracea (var. ceratea) on angiogenesis was evaluated. It displayed potent anti-angiogenic activities in vitro: inhibited proliferation of rat adipose tissue endothelial cells (RATECs) and disrupted endothelial tube formation in a dose-dependent manner. Furthermore, dose-dependent depolymerization effects of olivetoric acid on F-actin stress fibers were observed. Decrease in the tube formation of RATECs by olivetoric acid might be explained by a disorganization of the actin cytoskeleton. These findings suggest that olivetoric acid is a new anti-angiogenic agent and can be developed as a new therapeutic agent for angiogenesis-related diseases.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Células Endoteliales/efectos de los fármacos , Líquenes/química , Salicilatos/farmacología , Actinas/efectos de los fármacos , Tejido Adiposo/citología , Inhibidores de la Angiogénesis/aislamiento & purificación , Animales , Proliferación Celular , Células Cultivadas , Ratas , Salicilatos/aislamiento & purificación
6.
J Colloid Interface Sci ; 333(1): 40-8, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19217119

RESUMEN

The polymeric adsorbents were synthesized from 2-dimethylaminoethyl methacrylate (DMA) and [2-(methacryloyloxy)ethyl]dimethylhexadecylammonium bromide (DMAC(16)) monomers in the presence of ethylene glycol dimethacrylate (EDMA) cross-linking monomer using suspension polymerization technique and their adsorption efficiencies in the removal of p-nitrophenol from aqueous solutions were investigated. DMAC(16) monomer was prepared by means of modification of DMA monomer with 1-bromohexadecane. Adsorption experiments were carried out in a batch system and the experimental parameters were evaluated with respect to pH, agitation time, temperature and initial p-nitrophenol concentration. It was observed that the adsorbent poly[2-(methacryloyloxy)ethyl]dimethylhexadecylammonium bromide (p-DMAC(16)) prepared from DMAC(16) monomer was more effective in the removal of p-nitrophenol than the adsorbent poly(2-dimethylaminoethyl methacrylate) (p-DMA) prepared from DMA monomer. The effective pH ranges for the adsorption of p-nitrophenol onto p-DMAC(16) and p-DMA were 2-12 and 3-9, respectively. Langmuir and Freundlich adsorption models were used to describe the isotherms and find isotherm constants. The Langmuir model was well agreed with experimental data for both adsorbents. The pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetic models were used to understand the mechanism of the adsorption process and it fitted very well the pseudo-second-order kinetic model for each adsorbent. Thermodynamic parameters such as activation energy and changes of free energy, enthalpy, and entropy were also evaluated for the adsorption of p-nitrophenol onto each adsorbent. Additionally, reusability of the adsorbents was investigated and the results showed that both adsorbents can be employed many times without a significant loss in their adsorption capacities for the removal of p-nitrophenol from water.


Asunto(s)
Metacrilatos/síntesis química , Nitrofenoles/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Metacrilatos/química , Soluciones , Propiedades de Superficie , Termodinámica , Factores de Tiempo , Agua/química
7.
J Hazard Mater ; 165(1-3): 481-5, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19022575

RESUMEN

Lignocellulosic materials are good and cheap precursors for the production of activated carbon. In this study, activated carbons were prepared from the pyrolysis of soybean oil cake at 600 and 800 degrees C by chemical activation with K(2)CO(3) and KOH. The influence of temperature and type of chemical reagents on the porosity development was investigated and discussed. K(2)CO(3) was found more effective than KOH as a chemical reagent under identical conditions in terms of both porosity development and yields of the activated carbons. The maximum surface area (1352.86 m(2)g(-1)) was obtained at 800 degrees C with K(2)CO(3) activation which lies in the range of commercial activated carbons. Elemental analyses of the activated carbons indicate insignificant sulphur content for all activated carbons. The ash and sulphur contents of the activated carbons obtained with chemical activation by K(2)CO(3) were lower than those by chemical activation with KOH.


Asunto(s)
Carbón Orgánico/síntesis química , Aceite de Soja/química , Biomasa , Calor , Indicadores y Reactivos , Porosidad
8.
Parasitol Res ; 102(6): 1277-9, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18273644

RESUMEN

In this research, (-)-usnic acid and (+)-usnic acid, commonly encountered lichen secondary metabolites, were evaluated for their insecticidal effects against the larvae of Culex pipiens L. (Diptera: Culicidae) under laboratory conditions. Both compounds showed strong larvicidal activity and caused 100% mortality on third-fourth larval stages of the species at 24 h at the doses of 5 and 10 ppm. Bioassays with (-)- and (+)-usnic acids against larvae of C. pipiens revealed that the LC50 values were 0.8 and 0.9 ppm, respectively. The results suggest that lichen compounds could be useful in the search of new insecticides.


Asunto(s)
Benzofuranos/farmacología , Culex/efectos de los fármacos , Insecticidas/farmacología , Líquenes/química , Animales , Larva/efectos de los fármacos , Dosificación Letal Mediana , Estructura Molecular , Análisis de Supervivencia
9.
Bioresour Technol ; 99(14): 6214-22, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18207735

RESUMEN

Preparation of the activated carbons from sunflower oil cake by sulphuric acid activation with different impregnation ratios was carried out. Laboratory prepared activated carbons were used as adsorbents for the removal of methylene blue (MB) from aqueous solutions. Liquid-phase adsorption experiments were conducted and the maximum adsorption capacity of each activated carbon was determined. The effects of various process parameters i.e., temperature, pH, initial methylene blue concentration, contact time on the adsorption capacity of each activated carbon were investigated. The kinetic models for MB adsorption onto the activated carbons were studied. Langmuir isotherm showed better fit than Freundlich isotherm for all activated carbon samples. The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation. The separation factor (R(L)) revealed the favorable nature of the isotherm of the MB activated carbon system.


Asunto(s)
Biomasa , Carbono/aislamiento & purificación , Azul de Metileno/química , Ácidos Sulfúricos/química , Adsorción , Cinética , Temperatura
10.
Z Naturforsch C J Biosci ; 62(7-8): 619-21, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17913083

RESUMEN

The antimicrobial activity of the acetone, chloroform, diethyl ether, methanol, and petroleum ether extracts of the lichen Parmelia sulcata and its salazinic acid constituent have been screened against twenty eight food-borne bacteria and fungi. All of the extracts with the exception of the petroleum ether extract showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Yersinia enterocolitica, Staphylococcus aureus, Streptococcus faecalis, Candida albicans, Candida glabrata, Aspergillus niger, Aspergillus fumigatus, and Penicillium notatum. Salazinic acid did not show antimicrobial activity against L. monocytogenes, P. vulgaris, Y. enterocolitica, and S. faecalis but showed activity against Pseudomonas aeruginosa and Salmonella typhimurium as well. The MIC values of the extracts and the acid for the bacteria and fungi have also been determined.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Lactonas/farmacología , Líquenes/química , Salicilatos/farmacología , Bacterias/efectos de los fármacos , Liofilización , Hongos/efectos de los fármacos , Hidroxibenzoatos/aislamiento & purificación , Hidroxibenzoatos/farmacología , Lactonas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Salicilatos/aislamiento & purificación
11.
Z Naturforsch C J Biosci ; 61(7-8): 499-507, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16989308

RESUMEN

The antimicrobial activity and the MIC values of the ethanol, chloroform, diethyl ether, and acetone extracts of the chemical races of Pseudevernia furfuracea (var. furfuracea and var. ceratea) and their physodic acid, chloroatranorin, atranorin, and olivetoric acid constituents have been investigated against some microorganisms. Nearly all extracts of both chemical races showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans, Candida glabrata, Alternaria alternata, Ascochyta rabiei, Aspergillus niger, Fusarium culmorum, Fusarium moniliforme, Fusarium oxysporum, Fusarium solani, and Penicillium notatum. There was no antimicrobial activity of the extracts against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas syringae, Salmonella typhimurium, Alternaria citri, Alternaria tenuissima, and Gaeumannomyces graminis. Chloroatranorin and olivetoric acid were active against the same microorganisms with few exceptions. Physodic acid was active against about the same bacteria and yeasts and inactive against all of the filamentous fungi tested. Also no activity of atranorin against the filamentous fungi was observed.


Asunto(s)
Benzaldehídos/química , Benzaldehídos/farmacología , Dibenzoxepinas/química , Dibenzoxepinas/farmacología , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacología , Líquenes/química , Salicilatos/química , Salicilatos/farmacología , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antifúngicos/farmacología , Benzaldehídos/aislamiento & purificación , Dibenzoxepinas/aislamiento & purificación , Hidroxibenzoatos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Salicilatos/aislamiento & purificación
12.
Z Naturforsch C J Biosci ; 61(5-6): 319-23, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16869486

RESUMEN

The antimicrobial activity of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Xanthoparmelia pokornyi and its gyrophoric acid and stenosporic acid constituents has been screened against some foodborne bacteria and fungi. Both the extracts and the acids showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans and Candida glabrata. The extracts were inactive against the tested filamentous fungi. The MIC values of the extracts and the acids for the bacteria have also been determined.


Asunto(s)
Líquenes/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Candida/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Esporas/química
13.
Z Naturforsch C J Biosci ; 60(1-2): 35-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15787241

RESUMEN

The antimicrobial activity and the MIC values of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent have been investigated against some microorganisms. At least one of the extracts or 3-hydroxyphysodic acid showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Proteus vulgaris, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis, and Candida albicans. No antifungal activity of the extracts has been observed against ten filamentous fungi.


Asunto(s)
Antiinfecciosos/química , Dibenzoxepinas/química , Líquenes/química , Extractos Vegetales/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Candida albicans/efectos de los fármacos , Dibenzoxepinas/aislamiento & purificación , Dibenzoxepinas/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación
14.
Z Naturforsch C J Biosci ; 59(3-4): 249-54, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15241936

RESUMEN

The antimicrobial activity of the chloroform, diethyl ether, acetone, petroleum ether, and ethanol extracts of the lichen Cladonia foliacea and its (-)-usnic acid, atranorin, and fumarprotocetraric acid constituents against 9 bacteria and fungi has been investigated. The extracts and pure compounds alone were found active against the same bacteria and the same yeasts. Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Proteus vulgaris, Listeria monocytogenes, Aeromonas hydrophila, Candida albicans, and Candida glabrata growth were inhibited. In addition, the MICs of the extracts, (-)-usnic acid, atranorin and fumarprotocetraric acid were determined.


Asunto(s)
Antiinfecciosos/química , Ascomicetos/química , Bacterias/efectos de los fármacos , Benzofuranos/aislamiento & purificación , Candida/efectos de los fármacos , Fumaratos/aislamiento & purificación , Hidroxibenzoatos/aislamiento & purificación , Líquenes/química , Extractos Vegetales/aislamiento & purificación , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacterias/crecimiento & desarrollo , Benzofuranos/farmacología , Candida/crecimiento & desarrollo , Cromatografía en Capa Delgada , Fumaratos/farmacología , Hidroxibenzoatos/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología
15.
Z Naturforsch C J Biosci ; 59(5-6): 384-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-18998406

RESUMEN

The acetone extract of the lichen Ramalina farinacea and its (+)-usnic acid constituent showed antimicrobial activity against Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans, and Candida glabrata. Norstictic acid was active against Aeromonas hydrophila as well as the above microorganisms except Yersinia enterocolitica. Protocetraric acid showed activity only against the tested yeasts Candida albicans and Candida glabrata. The MIC values of the extract as well as of the three substances were determined. No antifungal activity of the acetone extract has been observed against ten filamentous fungi.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Benzofuranos/farmacología , Líquenes/química , Extractos Vegetales/farmacología , Levaduras/efectos de los fármacos , Acetona , Antibacterianos/aislamiento & purificación , Benzofuranos/química , Benzofuranos/aislamiento & purificación , Cromatografía en Capa Delgada , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación
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