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1.
Data Brief ; 52: 109810, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38076482

RESUMO

The data included in this article specify the characteristics of the Upper Miocene fill of the Turiec Basin and served for reconstruction of temporal evolution of depositional systems in this intermontane basin located within the Western Carpathians (Central Europe). The borehole lithological log data were used to describe the stratigraphy of the Turiec Basin in geological sections and were gained in the Geofond archive of the State Geological Institute of Dionýz Stúr. The sedimentological data were acquired by field research applying facies analysis to nine outcrop sites. The outcrops served for grain size analyzes performed by sieving and laser diffraction, for geochemical analyzes using ICP-ES, ICP-MS and XRF, and for mineralogical analyzes of whole rock and clay fraction by XRD. Moreover, the muddy layers on outcrops served for collection of 31 samples for the authigenic 10Be/9Be dating. The geochronological data are presented by using five different initial ratios for calculation, determined within the Turiec Basin at the Late Pleistocene alluvial fan and river terrace sites as well as at two Holocene muddy floodplain sites. Another initial ratio data are gained from an Upper Miocene lacustrine succession dated independently by magnetostratigraphy in previous research. Finally, a summary of previously published strontium isotope data from the Turiec Basin is included. The interpretations of the data are provided in Sujan et al., (2023) Palaeogeography, Palaeoclimatology, Palaeoecology 628, 111746.

2.
Molecules ; 27(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35164030

RESUMO

Xylanases are the enzymes that catalyze the breakdown of the main hemicellulose present in plant cell walls. They have attracted attention due to their biotechnological potential for the preparation of industrially interesting products from lignocellulose. While many xylanases have been characterized from bacteria and filamentous fungi, information on yeast xylanases is scarce and no yeast xylanase belonging to glycoside hydrolase (GH) family 30 has been described so far. Here, we cloned, expressed and characterized GH30 xylanase SlXyn30A from the yeast Sugiyamaella lignohabitans. The enzyme is active on glucuronoxylan (8.4 U/mg) and rhodymenan (linear ß-1,4-1,3-xylan) (3.1 U/mg) while its activity on arabinoxylan is very low (0.03 U/mg). From glucuronoxylan SlXyn30A releases a series of acidic xylooligosaccharides of general formula MeGlcA2Xyln. These products, which are typical for GH30-specific glucuronoxylanases, are subsequently shortened at the non-reducing end, from which xylobiose moieties are liberated. Xylobiohydrolase activity was also observed during the hydrolysis of various xylooligosaccharides. SlXyn30A thus expands the group of glucuronoxylanases/xylobiohydrolases which has been hitherto represented only by several fungal GH30-7 members.


Assuntos
Hidrolases/metabolismo , Xilosidases/metabolismo , Leveduras/enzimologia , Sequência de Aminoácidos , Hidrolases/química , Homologia de Sequência de Aminoácidos
4.
Int J Biol Macromol ; 103: 863-869, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28528945

RESUMO

Microalgae organisms are of interest for many biotechnology applications due to the production of a wide range of biologically active compounds. Incubation of Wollea saccata in a large scale afforded a mucilaginous, high molecular weight biopolymer composed of carbohydrate, protein and phenolic compounds. Sugar moiety was rich in hexoses (60%) and 6-deoxyhexoses (31%), while only 9% of pentoses was identified. Methylation analysis revealed about 40 types of methylated sugar derivatives, suggesting a very complex structure of Wollea biopolymer. Pharmacological studies revealed new pharmacodynamic properties of cyanobacteria biopolymer, i.e. antitussive and bronchodilatory. Biopolymer was able to suppress the cough reflex induced by chemical tussigen, but its effect was lower than that of codeine, the strongest antitussive agent. The bronchodilatory effect was similar or higher than the effect of salbutamol, a bronchodilatory drug used in a clinical practice. In pharmacological studies, there were no signs of toxicity or side effects in the animals following administration of Wollea biopolymer.


Assuntos
Biopolímeros/química , Biopolímeros/farmacologia , Cianobactérias/citologia , Espaço Extracelular/química , Animais , Antitussígenos/química , Antitussígenos/farmacologia , Broncodilatadores/química , Broncodilatadores/farmacologia , Cobaias , Masculino
5.
Bioorg Med Chem Lett ; 26(6): 1567-1570, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26896186

RESUMO

Reaction system was developed for enzymatic caffeoylation of model saccharidic acceptor methyl ß-d-glucopyranoside to obtain exclusively methyl 6-O-caffeoyl-ß-D-glucopyranoside. Reaction with starting concentration of acceptor 0.2 M provided 73% yield of purified product within 17 days. Reactions with low acceptor concentrations (0.04 and 0.08 M) run to the completion within 7 days. Such highly effective and regioselective reaction was promoted by Lipozyme TL IM in tert-butanol, using vinyl caffeate as acylation donor. The optimized reaction conditions were used in preparative caffeoylation of natural substances-arbutin and salidroside, giving 75% of 6-O-caffeoylated arbutin (robustaside B) and 74% of 6-O-caffeoylated salidroside as the only products after 12 and 16 days, respectively.


Assuntos
Produtos Biológicos/metabolismo , Ácidos Cafeicos/metabolismo , Glucosídeos/química , Glucosídeos/metabolismo , Lipase/metabolismo , Piranos/metabolismo , Produtos Biológicos/química , Ácidos Cafeicos/química , Glucosídeos/biossíntese , Estrutura Molecular , Piranos/química
6.
Anal Biochem ; 445: 49-53, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24135652

RESUMO

We have prepared 4-nitrophenyl caffeate by a combination of standard procedures of organic synthesis and enzymatic deacetylation. Based on hydrolysis of 4-nitrophenyl caffeate, a convenient spectrophotometric assay was developed for specific monitoring of caffeoyl esterase. The method is fast and easy to perform, and it requires no expensive equipment. Its reliability was tested on eight enzyme preparations comprising various combinations of caffeoyl, feruloyl, and acetyl esterase as well as protease activities.


Assuntos
Ácidos Cafeicos/química , Hidrolases de Éster Carboxílico/metabolismo , Nitrofenóis/química , Espectrofotometria , Biocatálise , Ácidos Cafeicos/síntese química , Ácidos Cafeicos/metabolismo , Ensaios Enzimáticos , Especificidade por Substrato
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