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1.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445267

RESUMO

The bacterial cellulose (BC) is a versatile biopolymer of microbial origin characterized by high purity and unusual water and material properties. However, the native BC contains a low number of functional groups, which significantly limits its further application. The main goal of its effective modification is to use methods that allow the unusual properties of BC to be retained and the desired functional group to be efficiently introduced. In the present study, the new magnetic carrier based on functionalized citric acid (CA) bacterial cellulose was developed and tested to support critical industrial enzymes such as lipase B from Candida antarctica and phospholipase A from Aspergillus oryzae. The applied method allowed BC to be effectively modified by citric acid and a sufficient number of carboxylic groups to be introduced, up to 3.6 mmol of COOH per gram of dry mass of the prepared carrier. The DSC and TGA analyses revealed carrier stability at operational temperatures in the range of 20 °C to 100 °C and substantially influenced the amount of the introduced carboxyl groups on carrier properties. Both enzymes' immobilization significantly improves their thermal stability at 60 °C without a significant thermal and pH optima effect. The analyzed enzymes showed good operational stability with a significant residual activity after ten cycles of repeated uses. The new magnetic carrier based on highly carboxylated bacterial cellulose has a high application capability as matrix for immobilization the various enzymes of industrial interest.


Assuntos
Aspergillus oryzae/enzimologia , Basidiomycota/enzimologia , Celulose/química , Enzimas Imobilizadas/química , Compostos Férricos/química , Proteínas Fúngicas/química , Lipase/química , Magnésio/química , Níquel/química , Fosfolipases A/química , Estabilidade Enzimática , Temperatura Alta
2.
Methods Mol Biol ; 2288: 113-126, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270008

RESUMO

Carrot is a vegetable of increasing economic importance. New hybrid cultivars are constantly required to meet the changing market needs. The application of anther culture significantly shortens the difficult and long-lasting breeding of carrot. We examined all the stages of the process of generating androgenic plants: induction of embryos in anther cultures, regeneration and acclimatization of produced plants, their evaluation, ploidy and homozygosity, and many other factors affecting their effectiveness. Every factor has been optimized by experimentally selecting the optimal level. As a result, a full protocol of producing homozygous plants using anther cultures was developed, which is presented in this chapter.


Assuntos
Daucus carota/crescimento & desenvolvimento , Daucus carota/genética , Melhoramento Vegetal/métodos , Aclimatação/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/fisiologia , Meios de Cultura/química , Daucus carota/fisiologia , Flores/genética , Flores/crescimento & desenvolvimento , Heterozigoto , Homozigoto , Isoenzimas/análise , Biologia Molecular/métodos , Regeneração/genética , Técnicas de Cultura de Tecidos
3.
Methods Mol Biol ; 2289: 301-312, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34270079

RESUMO

Hybrid varieties dominate the red beet market. The breeding process necessary to produce these cultivars is very difficult and time consuming. The application of in vitro gynogenesis can reduce the time needed to produce the corresponding homozygous pure lines to a few months. Our research team has developed a method to obtain red beet doubled haploid plants by gynogenesis. The best medium for gynogenesis induction is the B5 medium with the addition of 0.5 mg/L IAA, 0.2 mg/L BA, and 322 mg/L putrescine, whereas the best medium for shoot induction from embryos proved to be the MS medium supplemented with 0.1 mg/L NAA, 0.1 mg/L BA, and 0.5 mg/L putrescine. The shoots obtained were rooted on MS medium containing half the concentration of microelements and 3 mg/L NAA, 160 mg/L putrescine, and 20 g/L sucrose. Ploidy evaluation of gynogenetic plants was performed by flow cytometry and homozygosity or heterozygosity was determined by two isoenzymatic systems: PGI and AAT.


Assuntos
Beta vulgaris/efeitos dos fármacos , Óvulo Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Haploidia , Homozigoto , Melhoramento Vegetal/métodos , Regeneração/efeitos dos fármacos
4.
Int J Mol Sci ; 22(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803750

RESUMO

The mode of action of 1-naphthylphthalamic acid (NPA) to induce conspicuous local stem swelling in the area of its application to the growing internode in intact Bryophyllum calycinum was studied based on the aspects of histological observation and comprehensive analyses of plant hormones. Histological analyses revealed that NPA induced an increase in cell size and numerous cell divisions in the cortex and pith, respectively, compared to untreated stem. In the area of NPA application, vascular tissues had significantly wider cambial zones consisting of 5-6 cell layers, whereas phloem and xylem seemed not to be affected. This indicates that stem swelling in the area of NPA application is caused by stimulation of cell division and cell enlargement mainly in the cambial zone, cortex, and pith. Comprehensive analyses of plant hormones revealed that NPA substantially increased endogenous levels of indole-3-acetic acid (IAA) in the swelling area. NPA also increased endogenous levels of cytokinins, jasmonic acid, and its precursor, 12-oxo-phytodienoic acid, but did not increase abscisic acid and gibberellin levels. It was shown, using radiolabeled 14C-IAA, that NPA applied to the middle of internode segments had little effect on polar auxin transport, while 2,3,5-triiodobenzoic acid substantially inhibited it. These results strongly suggest that NPA induces changes in endogenous levels of plant hormones, such as IAA, cytokinins, and jasmonic acid, and their hormonal crosstalk results in a conspicuous local stem swelling. The possible different mode of action of NPA from other polar auxin transport inhibitors in succulent plants is extensively discussed.


Assuntos
Kalanchoe/citologia , Ftalimidas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Caules de Planta/fisiologia , Transporte Biológico/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Kalanchoe/anatomia & histologia , Caules de Planta/efeitos dos fármacos
5.
Carbohydr Polym ; 253: 117247, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33279002

RESUMO

In this work, we present a novel ex situ modification of bacterial cellulose (BC) polymer, that significantly improves its ability to absorb water after drying. The method involves a single inexpensive and easy-to-perform process of BC crosslinking, using citric acid along with catalysts, such as disodium phosphate, sodium bicarbonate, ammonium bicarbonate or their mixtures. In particular, the mixture of disodium phosphate and sodium bicarbonate was the most promising, yielding significantly greater water capacity (over 5 times higher as compared to the unmodified BC) and slower water release (over 6 times as compared to the unmodified BC). Further, our optimized crosslinked BC had over 1.5x higher water capacity than modern commercial dressings dedicated to highly exuding wounds, while exhibiting no cytotoxic effects against fibroblast cell line L929 in vitro. Therefore, our novel BC biomaterial may find application in super-absorbent dressings, designed for chronic wounds with imbalanced moisture level.


Assuntos
Absorção Fisico-Química , Bandagens , Materiais Biocompatíveis/química , Celulose/química , Reagentes para Ligações Cruzadas/química , Gluconacetobacter xylinus/metabolismo , Polissacarídeos Bacterianos/química , Cicatrização , Animais , Materiais Biocompatíveis/farmacologia , Catálise , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Celulose/farmacologia , Ácido Cítrico/química , Reagentes para Ligações Cruzadas/farmacologia , Fibroblastos/efeitos dos fármacos , Camundongos , Fosfatos/química , Polissacarídeos Bacterianos/farmacologia , Bicarbonato de Sódio/química , Água/química
6.
Carbohydr Polym ; 246: 116625, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747262

RESUMO

Bacterial cellulose (BC) is recognized as a wound dressing material well-suited for chronic wounds; however, it has no intrinsic antimicrobial activity. Further, the formation of biofilms can limit the effectiveness of the pre-saturation of BC with antimicrobial agents. Here, to hinder biofilm formation by P. aeruginosa, we immobilized the hydrolytic domain of PelA (a glycohydrolase involved in the synthesis of biofilm polysaccharide Pel) on the surface of BC. The immobilization of 32.35 ±â€¯1.05 mg PelAh per g BC membrane resulted in an eight-fold higher P. aeruginosa cell detachment from BC membrane, indicating reduced biofilm matrix stability. Further, 1D and 2D infrared spectroscopy analysis indicated systematic reduction of polysaccharide biofilm elements, confirming the specificity of immobilized PelAh. Importantly, BC-PelAh was not cytotoxic towards L929 fibroblast cells. Thus, we conclude that PelAh can be used in BC wound dressings for safe and specific protection against biofilm formation by P. aeruginosa.


Assuntos
Acetobacteraceae/química , Bandagens , Biofilmes/efeitos dos fármacos , Celulose/química , Glicosídeo Hidrolases/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Acetobacteraceae/fisiologia , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Biofilmes/crescimento & desenvolvimento , Linhagem Celular , Celulose/biossíntese , Celulose/isolamento & purificação , Clonagem Molecular , Enzimas Imobilizadas/biossíntese , Enzimas Imobilizadas/genética , Enzimas Imobilizadas/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Glicosídeo Hidrolases/biossíntese , Glicosídeo Hidrolases/genética , Camundongos , Domínios Proteicos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
7.
Biomed Res Int ; 2020: 6203053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32851084

RESUMO

Objectives: The aim of the study was to determine the quantitative and qualitative surface structure of contemporary RBCs in posterior teeth reconstructions: regular viscosity bulk fill and conventional composites, obtained after two-stage polishing procedure. Materials and Methods: Four conventional nanohybrid composites (Tetric EvoCeram, GrandioSO, Filtek Z550, and Ceram·X Mono) and four regular viscosity bulk fill composites (Tetric EvoCeram Bulk Fill, X-tra fil, Filtek Bulk Fill Posterior, and QuixFil) were tested. Samples of each RBC were prepared using PMMA cylindrical mold. After two-step polishing procedure, a surface geometry was evaluated under profilometry (Turbowave v. 7.36, Hommel-Etamic) and SEM (VEGA 3, Tescan Analytics). To evaluate differences between values, the following nonparametric tests were used: Friedman's ANOVA, Wilcoxon's matched-pair test, ANOVA Kruskal-Wallis, and Mann-Whitney U. Results: All conventional RBCs showed Ra values in the range of 0.20-0.26 µm. Bulk fill showed higher values in range of 0.49-1.36 µm except for Filtek Bulk Fill Posterior, which achieved 0.23 µm Ra value. SEM images of conventional RBCs were described as smooth surfaces with slight damage except for TEC, which presented smooth surface with no damage. Bulk fill composites showed rough surface, except for TBF, which presented smooth surface with slight damage. Conclusions: Regular viscosity bulk fill composites do not constitute a homogeneous group regarding surface roughness after polishing. They obtain, for the most part, poorer smoothness values after polishing than conventional RBCs.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Nanoestruturas/química , Resinas Compostas/uso terapêutico , Materiais Dentários/uso terapêutico , Humanos , Teste de Materiais , Nanoestruturas/uso terapêutico , Propriedades de Superfície , Viscosidade/efeitos dos fármacos
8.
Int J Mol Sci ; 21(8)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316348

RESUMO

The interaction of methyl jasmonate (JA-Me) and indole-3-acetic acid (IAA) to induce the formation of the secondary abscission zone in the middle of internode segments of Bryophyllum calycinum was investigated in relation to auxin status and histology. When IAA at 0.1% (w/w, in lanolin) was applied to the segments, the formation of the secondary abscission zone at a few mm above the treatment in the apical direction was observed. On the contrary, IAA at 0.5% (w/w, in lanolin) did not induce the formation of the secondary abscission zone. JA-Me at 0.5% (w/w, in lanolin) applied to the middle of internode segments kept in the normal (natural) or inverted positions also induced the formation of the secondary abscission zone below and above parts of the treatment. IAA at 0.5% applied to the cut surface of the upper part of the segments completely prevented the formation of the secondary abscission zone induced by JA-Me. Simultaneous application of IAA 0.5% with JA-Me 0.5% in the middle part of the internode segments induced the formation of the secondary abscission zone at 10 mm to 12 mm above the treatment. Histological analyses indicated that the formation of the secondary abscission zone was characterized by the presence of newly synthesized cell plates that resulted from periclinal cell division within one layer of mother cells in stems. The effects of IAA (0.1%) and JA-Me (0.5%) on the formation of the secondary abscission zone were histologically similar. Comprehensive analyses of plant hormones revealed that the balance of the endogenous levels of IAA in both sides adjacent to the abscission zone was significantly disturbed when the secondary abscission formation was induced by the application of IAA. These results strongly suggest that an auxin gradient is important in the formation of the secondary abscission zone in the internode segments of B. calycinum, and IAA gradient results from polar IAA transport from the application site. IAA is important in the regulation of formation of the secondary abscission zone induced by JA-Me. Further possible mechanisms of the formation of the secondary abscission zone in the internode segments of B. calycinum are also discussed in the interaction of JA-Me and IAA.


Assuntos
Acetatos/metabolismo , Ciclopentanos/metabolismo , Ácidos Indolacéticos/metabolismo , Kalanchoe/metabolismo , Oxilipinas/metabolismo , Acetatos/farmacologia , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/farmacologia , Kalanchoe/anatomia & histologia , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Caules de Planta/anatomia & histologia , Caules de Planta/efeitos dos fármacos
9.
Reumatologia ; 56(1): 31-36, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29686440

RESUMO

Introduction: Socio-demographic forecasts indicate a stable increase in the population of elderly people, which gives rise to the need to examine the relationship between the acceptance of chronic illness and socio-demographic variables not only in terms of subjective negative emotions but also because of possible social consequences. The acceptance of a chronic disease is determined by factors related to its character including its severity and the discomfort it brings about but also by factors connected with the patient that is socio-demographic determinants. Objective: The objective of the study was to examine the relationship between socio-demographic variables and the acceptance of a chronic disease of locomotive organs. Material and methods: The study was conducted in the group of 150 patients diagnosed with a systemic connective tissue disease during its stable phase. A socio-demographic questionnaire as well as a standardised Acceptance of Illness Scale (AIS) adapted by Juszczynski were applied in the study. The study was conducted in accordance with the recommendations of the Declaration of Helsinki. Results: In the group of 150 patients suffering from a systemic connective tissue disease the percentage of women was higher than the percentage of men (60.7% vs. 39.3%). The indicator of the acceptance of illness in the group examined reached 24.5 ±7.5. The strongest correlation was found between the acceptance level and married probants (eta = 0.26; p = 0.01), high education (eta = 0.24; p = 0.04) and working activity (eta = 0.20; p = 0.01). Conclusions: Socio-demographic factors which determine the level of illness acceptance include age, marital status, education and the source of income. The acceptance of illness in the examined group of patients with systemic connective tissue diseases reached 24.5.

10.
Artigo em Inglês | MEDLINE | ID: mdl-29670066

RESUMO

The aim of this study was to examine the influence of accelerated UV-aging on the activity against chosen microorganisms and the mechanical properties of poly-lactic acid (PLA) films enhanced with ZnO nanoparticles. The pure PLA films and tri-layered PLAZnO1%/PLA/PLAZnO1% films of 150 µm thickness were extruded. The samples were treated with UV-A and Q-SUN irradiation. After irradiation the antimicrobial activity and mechanical properties of the films were analyzed. The results of the study demonstrated that PLA films did not inhibit the growth of Staphylococcus aureus, Bacillus cereus, Escherichia coli, Bacillus atrophaeus, and Candida albicans cells. PLA films with incorporated zinc oxide nanoparticles decreased the number of analyzed microorganisms. Accelerated UV aging had no negative effect on the activity of the film containing nano-ZnO against Gram-positive bacteria, but it influenced the activity against Gram-negative cells and C. albicans. Q-SUN irradiation decreased the antimicrobial effect of films with incorporated nanoparticles against B. cereus. UV-A and Q-UV irradiation did not influence the mechanical properties of PLA films containing incorporated ZnO nanoparticles.


Assuntos
Anti-Infecciosos , Nanopartículas , Poliésteres , Raios Ultravioleta , Óxido de Zinco , Bactérias/crescimento & desenvolvimento , Candida albicans/crescimento & desenvolvimento
11.
Nanomaterials (Basel) ; 8(3)2018 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-29534544

RESUMO

Portions of fresh Baltic cod fillets were packed into cellulose boxes (control samples), which were covered with Methyl Hydroxypropyl Celluloses (MHPC) coating with 2% polylysine. The cellulose boxes had square PE films and were enclosed in MHPC coating containing ZnO nanoparticles. The cod fillets were stored at 5 °C and examined after 72 h and 144 h storage times. Results obtained in this study showed that the textural parameters of the cod fillets increased, with both Springiness and Cohesiveness found greater after 144 h of storage for all analysed packaging materials. The Gumminess of fillets increased after storage, but the lowest increase was noted in cod samples that were stored in boxes containing PE films with ZnO nanoparticles. It was found that water loss from the cod fillets in these boxes was also lowest. The Adhesiveness of the fish samples stored in boxes devoid of active coatings also increased. In contrast to the packaging material devoid of active coatings, the storage of fillets in active coating boxes resulted in a decrease of adhesiveness. Microbial analysis showed that packaging material containing nano-ZnO was found to be more active against mesophilic and psychotropic bacterial cells than the coatings with polylysine after 72 h and 144 h of storage.

12.
Polymers (Basel) ; 10(4)2018 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30966456

RESUMO

The purpose of this research was to examine the antimicrobial properties against Gram-positive bacteria, as well as the water vapour characteristic of polylactic acid (PLA) films covered with a methyl⁻hydroxypropyl⁻cellulose (MHPC)/cocoa butter carrier containing Eucomis comosa extract as an active substance. The second purpose of the study was to evaluate the influence of accelerated UV-A and Q-SUN irradiation (UV-aging) on the antimicrobial properties and the barrier characteristic of the coatings. The results of the study revealed that MHPC/cocoa butter coatings had no influence on the growth of Staphylococcus aureus, Bacillus cereus, and Bacillus atrophaeus. MHPC/cocoa butter coatings containing E. comosa extract reduced the number of bacterial strains. MHPC/cocoa butter coatings also decreased the water vapour permeability of PLA. It was shown that accelerated UV-A and Q-SUN irradiations altered the chemical composition of the coatings containing cocoa butter. Despite the alteration of the chemical composition of the layers, the accelerated Q-SUN and UV-A irradiation had no influence on the antimicrobial properties of E. comosa extract coatings against S. aureus and B. cereus. It was found that only Q-SUN irradiation decreased the coating activity with an extract against B. atrophaeus, though this was to a small degree.

13.
Plant Physiol Biochem ; 45(1): 54-61, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17303431

RESUMO

The influence of copper sulphate on the regeneration of carrot (Daucus carota L.) androgenic embryos and changes in the levels of phenolic substances and polyamines that might be indicative of the response to oxidative stress were investigated. The cultivation on the regeneration medium supplemented with Cu(2+) at the concentrations 1 and 10 microM for 15 weeks resulted in significant dose-dependent inhibition of the growth and organogenic ability of carrot embryos. The total content of phenolic acids (represented by the sum of all soluble and insoluble fractions) in the Cu(2+)-treated carrot cultures did not change in comparison with the control (0.1 microM Cu(2+)). However, the levels of phenolic acids in the individual fractions showed significant differences. The cultivation in the presence of increased Cu(2+) evoked first of all the rise of free chlorogenic and caffeic acids, and the increase in soluble ester-bound ferulic acid. Marked dose-dependent decline in the amount of ferulic acid incorporated into the cell walls of the Cu(2+)-treated carrot cultures was partly compensated by the increase in the content of p-hydroxybenzoic acid. Decline in the total polyamine contents in the carrot tissues cultivated in the presence of increased Cu(2+) concentrations was observed. The most abundant polyamine, both in a free and PCA-soluble conjugated forms, was putrescine, the least abundant was spermine, which occurred in free form only. While the levels of free polyamines slightly decreased in a dose-dependent manner in the Cu(2+)-treated cultures, those of PCA-soluble conjugates markedly rose (enhancement to 135 and 170% in 1 and 10 microM Cu(2+), respectively, compared with the control). The decline in the total polyamine contents was caused mainly by the decline in the levels of PCA-insoluble conjugates. The decrease observed in this fraction was approximately to 70 and 50% in 1 and 10 microM Cu(2+)-treated cultures, respectively, when compared with the control. The role of phenolic acids and polyamines in preventing Cu(2+)stress in the carrot tissues is discussed.


Assuntos
Sulfato de Cobre/farmacologia , Daucus carota/metabolismo , Fenóis/metabolismo , Poliaminas/metabolismo , Cadaverina/metabolismo , Células Cultivadas , Daucus carota/citologia , Daucus carota/crescimento & desenvolvimento , Cinética , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
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