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1.
Int J Biometeorol ; 68(1): 143-152, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37957435

RESUMO

A protocol study was designed to examine cutaneous behavior after continuous application of a peloid in the dry mineral residue of Lanjarón-Capuchina natural mineral water. This study aims to analyze the biomechanical behavior of normal skin using various non-invasive bioengineering techniques after the application of this peloid. We determine the effects of its application for 3 months on 38 healthy volunteers (41.4 ± 5.9 years, range 32-58) without a previous history of skin diseases by courtmetry, sebumetry, pH-metry, reviscometry, and tewametry. It was shown that the production of cutaneous sebum is significantly reduced by 6%, trans epidermal skin loss (TEWL) by 21%, skin fatigue by 30%, elasticity increased by 19%, firmness by 5%, and a skin redensification by 6% was obtained under these experimental conditions. Disparate and non-significant results were obtained concerning pH and viscoelasticity. Continuous skin care with the Lanjarón-Capuchina natural peloid modifies skin behavior, normalizing sebaceous secretion, favoring the biomechanical properties of the skin and the skin barrier function without modifying skin homeostasis.


Assuntos
Águas Minerais , Pele , Humanos , Minerais , Voluntários Saudáveis
2.
Bioengineering (Basel) ; 4(4)2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29182575

RESUMO

The effect of the addition of two [4-butyltrimethylammonium]-xylan chloride polyelectrolytes (BTMAXs) on bacterial cellulose (BC) was evaluated. The first strategy was to add the polyelectrolytes to the culture medium together with a cell suspension of the bacterium. After one week of cultivation, the films were collected and purified. The second approach consisted of obtaining a purified and homogenized BC, to which the polyelectrolytes were added subsequently. The films were characterized in terms of tear and burst indexes, optical properties, surface free energy, static contact angle, Gurley porosity, SEM, X-ray diffraction and AFM. Although there are small differences in mechanical and optical properties between the nanocomposites and control films, the films obtained by BC synthesis in the presence of BTMAXs were remarkably less opaque, rougher, and had a much lower specular gloss. The surface free energy depends on the BTMAXs addition method. The crystallinity of the composites is lower than that of the control material, with a higher reduction of this parameter in the composites obtained by adding the BTMAXs to the culture medium. In view of these results, it can be concluded that BC-BTMAX composites are a promising new material, for example, for paper restoration.

3.
Appl Spectrosc ; 70(9): 1537-45, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27129363

RESUMO

A new method was developed to study how the oil and cyan pigments of cold-set ink are distributed in newspaper thickness. The methodology involved laboratory printing followed by delamination of the printed paper. The unprinted side, printed side, and resulting layers were analyzed using attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR). Three commercial newspapers and black and cyan cold-set inks were chosen for the study. Attenuated total reflection Fourier transform infrared spectroscopy enabled the proportion of oil and cyan pigment on the printed surface and throughout the sheet thickness to be measured. Oil percentage was evaluated as the area increment of the region from 2800 cm(-1) to 3000 cm(-1) The relative amount of cyan pigment was determined as the area of the absorption band at 730 cm(-1) The ink oil was found mainly below half the paper thickness, whereas the pigment was detected at the layers closer to the printed surface, at a depth penetration of less than 15 µm (20% of thickness). Distribution of these two components in paper thickness depended on the type of cold-set ink, the amount of ink transferred, and the newspaper properties.

4.
Carbohydr Polym ; 116: 173-81, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25458287

RESUMO

Bacterial cellulose (BC) synthesized by Gluconacetobacter sucrofermentans CECT 7291 seems to be a good option for the restoration of degraded paper. In this work BC layers are cultivated and purified by two different methods: an alkaline treatment when the culture media contains ethanol and a thermal treatment if the media is free from ethanol. The main goal of these tests was the characterization of BC layers measured in terms of tear and burst indexes, optical properties, SEM, X-ray diffraction, FTIR, degree of polymerization, static and dynamic contact angles, and mercury intrusion porosimetry. The BC layers were also evaluated in the same terms after an aging treatment. Results showed that BC has got high crystallinity index, low internal porosity, good mechanical properties and high stability over time, especially when purified by the alkaline treatment. These features make BC an adequate candidate for degraded paper reinforcement.


Assuntos
Celulose/química , Papel , Celulose/isolamento & purificação , Celulose/metabolismo , Etanol/química , Gluconacetobacter/metabolismo , Temperatura Alta , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Difração de Raios X
5.
Fungal Genet Biol ; 41(10): 954-62, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15341917

RESUMO

Nine phenolic compounds (p-coumaric acid, ferulic acid, guaiacol, syringol, p-methoxyphenol, pyrocatechol, phloroglucinol, 3,5-dihydroxybenzoic acid, and syringaldazine) were tested for their ability to increase laccase production in the ligninolytic basidiomycete Trametes sp. I-62. All these compounds resulted in increases in laccase activity, with the highest levels being detected in the presence of p-coumaric acid (273-fold) and guaiacol (73-fold). The three laccase isozyme genes in this fungus lcc1, lcc2, and lcc3 are differentially expressed in the presence of some of these aromatics with total lcc transcript levels differing markedly depending on the aromatic compound tested. Guaiacol (the best inducer of lcc gene transcription) and p-coumaric acid selectively induced expression of lcc1 and lcc2; ferulic acid induced lcc3 expression, while 3,5-dihydroxybenzoic acid had no marked effect on laccase gene transcription. The results demonstrate that close-related aromatic compounds appear to have different effects on both laccase activity levels and lcc gene expression in this basidiomycete.


Assuntos
Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hidrocarbonetos Aromáticos/farmacologia , Lacase/metabolismo , Polyporales/enzimologia , Ácidos Cumáricos/farmacologia , Ativadores de Enzimas/farmacologia , Expressão Gênica , Genes Fúngicos , Guaiacol/farmacologia , Hidroxibenzoatos/farmacologia , Isoenzimas/genética , Lacase/biossíntese , Fenóis/farmacologia , Polyporales/genética , Propionatos , RNA Fúngico/análise , RNA Fúngico/biossíntese , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Resorcinóis , Transcrição Gênica
6.
J Basic Microbiol ; 44(2): 79-87, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15069666

RESUMO

The study of isozymes has to date been successfully applied in the identification of a number of different microorganisms, particularly fungi. Trametes sp. I-62 (CECT20197) is a white-rot fungus with potential biotechnological applications. It has been identified as Trametes on the basis of the mycelium morphology, but the features observed are not sufficient for its classification at the species level. Given that this strain produces a very characteristic laccase isozyme pattern, in the present work we compared its isozyme profile with the profiles produced by ten other very closely phylogenetically related fungi from the Polyporaceae family. The data indicates that Trametes sp. I-62 could not be included in any of the taxonomically related species which were analysed in the present work. Extracellular laccases were detected in nine of the fungi studied and in four of them namely Trametes subectypus, Trametes pavonia, Trametes ochracea and Trametes gallica, this is the first report of such activity. Given that phylogenetically related fungi growing in the same culture conditions exhibit different laccase patterns, these isozymes could be used as an additional criterion for fungal identification.


Assuntos
Lacase/metabolismo , Polyporaceae/enzimologia , Meios de Cultura , Isoenzimas/metabolismo , Polyporaceae/crescimento & desenvolvimento , Especificidade da Espécie , Fatores de Tempo
7.
Appl Environ Microbiol ; 69(12): 7083-90, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14660352

RESUMO

Laccases produced by white rot fungi are involved in the degradation of lignin and a broad diversity of other natural and synthetic molecules, having a great potential for biotechnological applications. They are frequently encoded by gene families, as in the basidiomycete Trametes sp. strain I-62, from which the lcc1, lcc2, and lcc3 laccase genes have been cloned and sequenced. A multiplex reverse transcription-PCR method to simultaneously study the expression of these genes was developed in this study. The assay proved to be quick, simple, highly sensitive, and reproducible and is particularly valuable when numerous samples are to be analyzed and/or if the amount of initial mRNA is limited. It was used to analyze the effect of 3,4-dimethoxybenzyl alcohol (veratryl alcohol) and two of its isomers (2,5-dimethoxybenzyl alcohol and 3,5-dimethoxybenzyl alcohol) on differential laccase gene expression in Trametes sp. strain I-62. These aromatic compounds produced different induction patterns despite their chemical similarity. We found 2,5-dimethoxybenzyl alcohol to be the best inducer of laccase activity while also producing the highest increase in gene expression; 3,5-dimethoxybenzyl alcohol was the next best inducer. Transcript amounts of each gene fluctuated dramatically in the presence of these three inducers, while the total amounts of laccase mRNAs seemed to be modulated by a coordinated regulation of the different genes.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/crescimento & desenvolvimento , Regulação Fúngica da Expressão Gênica , Lacase/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Basidiomycota/genética , Álcoois Benzílicos/metabolismo , Meios de Cultura/química , Isomerismo , Lacase/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Can J Microbiol ; 48(12): 1041-7, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12619815

RESUMO

Laccase, a phenoloxidase enzyme secreted by white-rot fungi, has a significant role in the degradation of lignin and environmental pollutants. Coriolopsis gallica is a ligninolytic basidiomycete that produces high levels of this extracellular enzyme. A laccase gene cglcc1 from this fungus has been cloned and sequenced. The capacity of C. gallica to efficiently degrade polyphenols has been successfully applied in our laboratory to the biotreatment and decolorization of several industrial wastewaters. This study focused on the effect of tannic acid, a natural compound widely distributed in plants, on the production of laccase activity by C. gallica. Our results showed an evident increase of extracellular laccase levels when C. gallica was grown in the presence of tannic acid. Concentrations of 50 and 100 microM of this compound increased laccase activity when compared with control samples grown without tannic acid. In addition, we found an increase in laccase transcript levels in C. gallica grown in culture media supplemented with tannic acid. The role of tannic acid was shown to be an inductor of laccase activity in this fungus, due to the enhancement of expression of the laccase gene at the transcriptional level.


Assuntos
Regulação Fúngica da Expressão Gênica , Taninos Hidrolisáveis/farmacologia , Oxirredutases/genética , Polyporales/enzimologia , Transcrição Gênica , Sondas de DNA , Indução Enzimática , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/metabolismo , Lacase , Dados de Sequência Molecular , Concentração Osmolar , Polyporales/classificação , Polyporales/genética , Polyporales/metabolismo , Espectrofotometria/métodos , Fatores de Tempo
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