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1.
Int J Biol Macromol ; 125: 124-132, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30521917

RESUMO

The polyphenolic-polysaccharide complex was isolated from the dried aerial parts of the medicinal plant Agrimonia eupatoria L. using a multi-step process involving the degreasing of the plant material by extraction with organic solvents, followed by extraction with hot alkali, neutralization, further separation with organic solvents and dialysis. The complex was homogeneous with a molecular weight of about 55 × 103 g/mol and consisted mainly of carbohydrates and polyphenols matrix, composed of lignin-related units, with the dominance of dimethoxyphenyl structures. The carbohydrate moiety consists mostly of arabinogalactan associated with highly esterified rhamnogalacturonan. In vitro anticoagulant studies revealed the ability of the A. eupatoria complex to inhibit plasma clot formation, mainly in the intrinsic pathway of the blood coagulation cascade. Further studies on the mechanisms of this anticoagulant activity revealed that the isolate was primarily an indirect inhibitor of thrombin, mediated by antithrombin or by heparin cofactor II. Such mechanism of action is characteristic for highly sulfated glycosaminoglycans.


Assuntos
Agrimonia/química , Anticoagulantes/química , Anticoagulantes/farmacologia , Polifenóis/química , Polissacarídeos/química , Animais , Anticoagulantes/isolamento & purificação , Coagulação Sanguínea/efeitos dos fármacos , Humanos , Metilação , Peso Molecular , Compostos Fitoquímicos/química , Análise Espectral
2.
Biotechnol Biofuels ; 10: 259, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29151888

RESUMO

BACKGROUND: Pig manure utilization and valorization is an important topic with tightening regulations focused on ecological and safety issues. By itself pig manure is a poor substrate for biogas production because of its excessive nitrogen content relative to available organic carbon. Such substrate is alkaline, and methanogenesis can be suppressed, and so additional substrates with high organic carbon must be added. The most promising is straw, which is available from adjacent biogas plant cultures. However, the abundant lignocellulosic biomass of wheat straw undergoes slow decomposition, and only a fraction of the chemical energy can be converted into biogas; thus economical methods for pretreatment increasing bioavailability are sought. RESULTS: A method was investigated to increase the methane yield in a full-scale plant for co-fermenting pig manure with corn silage, which was the default substrate in the original source reactors. Increased lignocellulosic bioavailability of wheat straw was achieved by combining liquid hot water (LHW) and steam explosion (SE). According to FT-IR analysis, the treatment resulted in hemicellulose hydrolysis, partial cellulose depolymerization, and lignin bond destruction. Low-mass polysaccharides (0.6 × 103 g mol-1) had significantly higher concentration in the leachate of LHW-SE wheat straw than raw wheat straw. The methanogenic potential was evaluated using inoculum from two different biogas plants to study the influence of microorganism consortia. The yield was 24-34% higher after the pretreatment process. In a full-scale biogas plant, the optimal conditions were ~ 165 °C, ~ 2.33 MPa, and 10 min in LHW and ~ 65 °C and ~ 0.1 MPa for SE. The processes did not generate detectable inhibitors according to GC-MS analysis, such as furfural and 5-hydroxymethylfurfural. CONCLUSIONS: The LHW-SE combined pretreatment process increases the bioavailability of carbohydrates from wheat straw. The LHW-SE treated wheat straw gave similar biogas yields to corn silage, thus enables at least partial replacement of corn silage and is good for diversification of substrates. Surprisingly, microorganisms consortia from other biogas plant fed with other substrates may have higher efficiency in utilization of tested substrate. Thus, methanogenic consortia may be considered in the process of optimization at industrial scale. The efficiency was calculated, and the LHW-SE may be profitable at full industrial scale and further optimization is proposed.

3.
Int J Biol Macromol ; 93(Pt A): 1019-1029, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27664921

RESUMO

A macromolecular complex has been isolated from the dried flowering parts of medicinal plant Sanguisorba officinalis L. (So) by multi-step extraction procedure, including that with extraction by organic solvents to degrease the plant material, then with hot alkali, followed by neutralization, partitioning with organic solvents and dialysis. The complex was purified by size-exclusion chromatography into five fractions labeled as So1-So5. Individual fractions differed in the chemical composition and molecular weight distribution patterns. In vitro anticoagulant activity tests showed in all fractions more or less important inhibition of plasma clots, however, So3 and So4 were the most active. The anticoagulant activity of So3 was even more significant than that of the unfractionated complex So. These S. officinalis conjugates were able to inhibit mainly the activity of thrombin when they were mediated by heparin cofactor II, but what was unexpected they were the non-direct inhibitors of factor Xa, mediated by antitrombin, where such mechanism of action is typical for a highly sulphated glycosaminoglycans.


Assuntos
Anticoagulantes/farmacologia , Cofator II da Heparina/fisiologia , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Polissacarídeos/farmacologia , Anticoagulantes/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos , Flores/química , Humanos , Tempo de Tromboplastina Parcial , Extratos Vegetais/isolamento & purificação , Polifenóis/isolamento & purificação , Polissacarídeos/isolamento & purificação , Tempo de Protrombina , Sanguisorba/química
4.
Przegl Lek ; 70(3): 131-4, 2013.
Artigo em Polonês | MEDLINE | ID: mdl-24003667

RESUMO

Over last few years, biosensors have become increasingly used as a research tool. Using innovative techniques of detection and estimation of the strength of intermolecular bonds, is particularly important in biochemical processes, including the study of mechanisms of interactions between plasma proteins in the circulatory system. With the numerous enhancements biosensors have become extremely sensitive devices, allowing for analysis of diverse biological material. Moreover, the use of immobilization techniques enables to use sample repeatedly, which significantly reduces costs and the ability to monitor tests in real-time shorten the time of experiment. The presented work discusses examples of the usage of biosensors in the research on the mechanisms of the interactions of blood plasma proteins. The experiments on cancer biomarkers present in the blood circulation system, protein C deficiency causing non-controlled hemorrhagic accidents, and on the level of fibrinogen, as well as 20S proteasome concentration in plasma, are just some examples of biosensors usage in the analyses of blood. They are also applicable in the research work performed the project WROVASC--Integrated Cardiovascular Center, concerning the mechanisms of anticoagulant activity in blood plasma of the polyphenolic-polysaccharide macromolecules of plant origin.


Assuntos
Biomarcadores Tumorais/sangue , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Proteínas Sanguíneas/análise , Anticoagulantes/sangue , Biomarcadores/sangue , Técnicas Biossensoriais/economia , Controle de Custos , Hemorragia/sangue , Humanos
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