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1.
Chem Pharm Bull (Tokyo) ; 67(8): 849-854, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366834

RESUMO

Regenerative therapy with keratinocyte growth factor (KGF) is a novel therapeutic approach for treatment of chronic wounds. However, KGF cannot be used directly to the wound site due to its physicochemical instability. In previous study, sacran, a natural megamolecular polysaccharide, showed potential properties as a biomaterial for hydrogel film in wound healing. In this study, we fabricated sacran hydrogel film containing KGF (Sac/KGF-HF) and evaluated the effects of Sac/KGF-HF on fibroblasts migration and re-epithelialization process. We successfully prepared a homogenous and -amorphous Sac/KGF-HF by a casting method. In addition, Sac/KGF-HF had a high swelling ratio and flexibility. Sac/KGF-HF promoted a migration process of NIH3T3 cells and improved wound healing ability in mice with a percentage of wound closure reaching 90.4% at 9 d. Interestingly, the addition of KGF in Sac-HF considerably increased the number of epithelial cells compared to control, which is important in the re-epithelialization process. It could be concluded that KGF in Sac-HF has the potential for promoting Sac-HF abilities in wound healing process.


Assuntos
Fator 7 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Metilgalactosídeos/farmacologia , Polissacarídeos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fator 7 de Crescimento de Fibroblastos/química , Metilgalactosídeos/química , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Polissacarídeos/química
2.
Pestic Biochem Physiol ; 158: 149-155, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378351

RESUMO

Induced resistance is an effective measure for controlling plant diseases by utilizing the natural defense of the host and meets the strategic needs of pesticide application and safety for agricultural products worldwide. Ganoderma lucidum polysaccharide (GLP), which is the main active molecule of G. lucidum, has been widely used in functional food and clinical medicine. However, there are few reports of the use of GLP for the prevention and control of plant diseases. The purpose of this study is to explore the effect of GLP and its mechanism of inducing plant resistance. In this study, we found that GLP spray and irrigation root treatments can promote growth in cotton. After soaking in GLP, theseedling height and cotton fusarium wilt resistance both increased to some extent, effects that were dose dependent. After treatment of cotton with GLP, the activities of peroxidase (POD), superoxide dismutase (SOD) and polyphenol oxidase (PPO) in leaves increased significantly, whereas the content of malondialdehyde (MDA) decreased. In addition, QRT-PCR results showed significantly increased relative expression of genes related to the jasmonic acid pathway in cotton. Therefore, we speculate that GLP can induce plant resistance by stimulating the jasmonate pathway.


Assuntos
Fusarium/efeitos dos fármacos , Gossypium/microbiologia , Polissacarídeos/farmacologia , Reishi/química , Antioxidantes/metabolismo , Gossypium/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Doenças das Plantas/microbiologia , Polissacarídeos/química , Superóxido Dismutase/metabolismo
3.
J Chem Phys ; 151(3): 034504, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31325935

RESUMO

Although by now the glass transition temperature of uncrystallized bulk water is generally accepted to manifest at temperature Tg near 136 K, not much known are the spectral dispersion of the structural α-relaxation and the temperature dependence of its relaxation time τα,bulk(T). Whether bulk water has the supposedly ubiquitous Johari-Goldstein (JG) ß-relaxation is a question that has not been answered. By studying the structural α-relaxation over a wide range of temperatures in several aqueous mixtures without crystallization and with glass transition temperatures Tg close to 136 K, we deduce the properties of the α-relaxation and the temperature dependence of τα,bulk(T) of bulk water. The frequency dispersion of the α-relaxation is narrow, indicating that it is weakly cooperative. A single Vogel-Fulcher-Tammann (VFT) temperature dependence can describe the data of τα,bulk(T) at low temperatures as well as at high temperatures from neutron scattering and GHz-THz dielectric relaxation, and hence, there is no fragile to strong transition. The Tg-scaled VFT temperature dependence of τα,bulk(T) has a small fragility index m less than 44, indicating that water is a "strong" glass-former. The existence of the JG ß-relaxation in bulk water is supported by its equivalent relaxation observed in water confined in spaces with lengths of nanometer scale and having Arrhenius T-dependence of its relaxation times τconf(T). The equivalence is justified by the drastic reduction of cooperativity of the α-relaxation in nanoconfinement and rendering it to become the JG ß-relaxation. Thus, the τconf(T) from experiments can be taken as τß,bulk(T), the JG ß-relaxation time of bulk water. The ratio τα,bulk(Tg)/τß,bulk(Tg) is smaller than most glass-formers, and it corresponds to the Kohlrausch α-correlation function, exp[-(t/τα,bulk)1-n], having (1-n) = 0.90. The dielectric data of many aqueous mixtures and hydrated biomolecules with Tg higher than that of water show the presence of a secondary ν-relaxation from the water component. The ν-relaxation is strongly connected to the α-relaxation in properties, and hence, it belongs to the special class of secondary relaxations in glass-forming systems. Typically, its relaxation time τν(T) is longer than τß,bulk(T), but τν(T) becomes about the same as τß,bulk(T) at sufficiently high water content. However, τν(T) does not become shorter than τß,bulk(T). Thus, τß,bulk(T) is the lower bound of τν(T) for all aqueous mixtures and hydrated biomolecules. Moreover, it is τß,bulk(T) but not τα(T) that is responsible for the dynamic transition of hydrated globular proteins.


Assuntos
Biopolímeros/química , Modelos Químicos , Água/química , Animais , Dissacarídeos/química , Glicogênio/química , Monossacarídeos/química , Mytilus/química , Polissacarídeos/química , Ribonuclease Pancreático/química , Termodinâmica
4.
Food Chem ; 298: 125079, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260959

RESUMO

Citral-in-water emulsions were prepared with two different essential oil concentrations of 2.5 and 5.0% (w/w), then spray-dried in the presence of the same amount of maltodextrins (20%). The microcapsules were prepared with two different emulsifier compositions: monolayer microcapsules (ML) stabilized by sodium caseinate alone and layer-by-layer microcapsules (LBL) stabilized by sodium caseinate and pectin. The encapsulation efficiency was higher for LBL microcapsules (e.g. 99.6 ±â€¯0.4% for 2.5% citral) than that for ML ones (e.g. 78.6 ±â€¯0.6% for 2.5% citral) which confirm that the additional pectin layer was able to protect citral during the spray-drying process whatever citral concentration. Furthermore, our results showed that the antibacterial activity of the obtained microcapsules significantly depends on both citral concentration and interfacial membrane composition. The presence of two layers surrounding the citral droplets may result in a progressive and controlled release of the encapsulated citral.


Assuntos
Emulsões/química , Monoterpenos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cápsulas/química , Caseínas/química , Dessecação , Listeria/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Tamanho da Partícula , Pectinas/química , Polissacarídeos/química , Staphylococcus aureus/efeitos dos fármacos
5.
Bioresour Technol ; 291: 121868, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357045

RESUMO

To clarify the adsorption behaviors of typical heavy metals onto sludge extracellular polymeric substances (EPS), the adsorption capacities and mechanisms, as well as the contributions of the different EPS components (proteins, humic acids and polysaccharides), to the adsorption of Zn2+, Cu2+ and Cd2+ were separately explored. Overall, proteins exhibited a relatively high adsorption capacity for the three metals ions, followed by humic acid, whereas least for polysaccharides. The adsorption of Cu2+ and Cd2+ onto proteins, humic acid and polysaccharides fit well to the Freundlich isotherm, whereas Langmuir model was the best fit for Zn2+ bindings onto polysaccharides/humic acid. The binding of Cu2+, Zn2+ and Cd2+ onto the three EPS components was exothermically favorable, and significant electrostatic interactions were observed for the heavy metals sorption onto humic acid and proteins. In addition, the effect of metal ions sorption on the spectrum of the proteins, polysaccharides and humic acid was also explored.


Assuntos
Cádmio/química , Cobre/química , Substâncias Húmicas , Polissacarídeos/química , Proteínas/metabolismo , Esgotos , Zinco/química , Adsorção , Cádmio/metabolismo , Cobre/metabolismo , Proteínas/química , Esgotos/química , Zinco/metabolismo
6.
Food Chem ; 298: 125041, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261000

RESUMO

Edible packaging films play an important role in extending the shelf life of food products. In this work, the properties of cellulose nanofiber (CNF) reinforced hemicelluloses/chitosan-based edible films with xylooligosaccharides (XOS) have been evaluated. Results showed that the tensile strength (TS) of the film can be increased by 2.5 times with adding 5 wt% CNF. Incorporating 1.79-7.18% XOS into hemicelluloses-chitosan matrix only caused slightly higher water vapor permeability, and the composite films exhibited good hydrophobicity, thermal stability, and high transparency. The hemicelluloses/chitosan films with 1.79-5.38% XOS had higher TS (42.7-50.7 MPa) and lower oxygen permeability (OP, 4.95-5.06 cm3 µm/m2·day·kPa) than those containing 7.18% XOS. Additionally, ∼92.6% XOS in films can be released in simulated gastric fluid within 60 min. Overall, XOS (1.79-5.38%) with prebiotic properties can be added to films successfully to improve the functionality and the films were fit for food-packaging where high TS and low OP are required.


Assuntos
Celulose/química , Quitosana/química , Glucuronatos/química , Nanofibras/química , Oligossacarídeos/química , Embalagem de Alimentos/métodos , Suco Gástrico , Humanos , Microscopia Eletrônica de Varredura , Permeabilidade , Polissacarídeos/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Difração de Raios X
7.
Food Chem ; 298: 125023, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260964

RESUMO

This research investigated the effect of pH on forming electrostatic complexes between lentil protein isolate (LPI) and a range of anionic polysaccharides [carboxymethyl cellulose (CMC), gum Arabic (GA), alginate (AL), and ι-carrageenan (CAR)] at 4:1 LPI-polysaccharide mixing ratio, and their resulting emulsifying abilities. Maximum optical densities were found to be 0.486, 0.716, 0.310, and 0.190 for LPI-CMC, LPI-GA, LPI-AL, and LPI-CAR, respectively indicating the level of aggregate size and growth. LPI-CAR emulsion displayed the highest emulsion stability (ES) because of its higher continuous phase and emulsion viscosities, lower mean droplet sizes, and negatively charged droplets. They also formed much smaller complexes within solution due to their high negative charge. All other LPI-polysaccharide systems formed less stable emulsions than LPI alone due to the larger sizes of both complexes and oil droplets.


Assuntos
Ânions/química , Lens (Planta)/química , Proteínas de Plantas/química , Polissacarídeos/química , Alginatos/química , Carboximetilcelulose Sódica/química , Carragenina/química , Emulsões , Goma Arábica/química
8.
Zhongguo Zhong Yao Za Zhi ; 44(9): 1822-1828, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31342708

RESUMO

The flower of Hibiscus syriacus has good ornamental and edible-medicinal values.In this study,four samples of two varieties,namely white multiple petals flower and pink multiple petals flower,were selected as test materials.And the optimum extraction conditions,relative molecular weight,monosaccharide composition and antioxidant activity of polysaccharides in flower were investigated.Through single factor experiment and response surface,the optimal extract conditions of polysaccharide were designed as follows:extraction temperature at 96.8℃,ratio of material to liquid of 43.5∶1 m L·g~(-1),extraction time of 3.1 h.Polysaccharides of H.syriacus flowers were analyzed by high performance gel chromatography.The average molecular masses of the 4 polysaccharide samples were1.49×10~5,1.25×10~5,1.01×10~5,1.37×10~5,respectively.Polysaccharides of H.syriacus flowers were mainly composed of glucose,mannose,galactose,rhamnose and arabinose by pre-column derivatization HPLC.The ratio of galactose was the highest in five monosaccharide,and the ratio of galactose to glucose was 1.656-4.496.In addition,crude polysaccharides of H.syriacus flowers showed potential antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl radical(DPPH)assay,total reducing capacity assay and ABTS assay in vitro,and its antioxidant effect showed a good dose-effect relationship with the concentration of crude polysaccharides.Among the tested varieties,polysaccharides of pink multiple petals flower and white multiple petals flower had the same molecular masses and monosaccharides composition,but the antioxidant activity of the polysaccharides of pink multiple petals flower was higher than that of the white flowers.The results of this study can provide a theoretical basis for the application of H.syriacus flower in the field of functional foods.


Assuntos
Antioxidantes/farmacologia , Hibiscus/química , Polissacarídeos/farmacologia , Antioxidantes/química , Flores/química , Monossacarídeos/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Pigmentação , Polissacarídeos/química
9.
Chem Biol Interact ; 308: 258-268, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150630

RESUMO

The reactive oxygen species (ROS) induced oxidative stress is an inevitable factor for the pathogenesis of cardiovascular diseases. The edible marine algae-derived sulfated polysaccharides gained special attention as novel bioactive compounds having potential pharmacological activities. The present study evaluated in vitro and in vivo cardioprotective properties of sulfated polysaccharides from the edible brown marine algae Padina tetrastromatica (PSPS) against isoproterenol (ISO) induced cardiac damage. The cardioprotective properties of PSPS were first evaluated in H9c2 cardiac myoblasts and the results were confirmed by in vivo studies conducted in male Sprague-Dawley rats. The biochemical parameters, histopathological analysis, mRNA expressions, and ELISA studies indicated that PSPS significantly decreased (p < 0.05) the cardiac damage induced by ISO by reducing lipid peroxidation and improving antioxidant status, both in vitro and in vivo, via modulating PI3k/Akt/Nrf2 signaling pathway. The histopathological evidence further reinforced our findings and highlighted the promising cardioprotective activities offered by PSPS.


Assuntos
Isoproterenol/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Feófitas/metabolismo , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Linhagem Celular , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Polissacarídeos/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Sulfatos/química
10.
J Agric Food Chem ; 67(25): 7040-7049, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31199141

RESUMO

Obesity is a metabolic syndrome worldwide that causes many chronic diseases. Recently, we found an antiobesity effect of flaxseed polysaccharide (FP), but the mechanism remains to be elucidated. In this study, rats were first induced to develop obesity by being fed a high-fat diet. The obese rats were then fed a control diet, AIN-93M (group HFD), or a 10% FP diet (group FPD). The body weight, body fat, adipose tissue and liver sections, serous total triglycerides, levels of fasting blood glucose in serum, serous insulin, inflammatory cytokines in serum, and serous proteins within the leptin-neuropeptide Y (NPY) and AMP-activated protein kinase (AMPK) signaling pathway were determined and analyzed. FP intervention significantly reduced body weight and abdominal fat from 530 ± 16 g and 2.15% ± 0.30% in group HFD to 478 ± 10 g and 1.38% ± 0.48% in group FPD, respectively. This effect was achieved by removing leptin resistance possibly by inhibiting inflammation and recovering satiety through the significant downregulation of NPY and the upregulation of glucagon-like peptide 1. Adiponectin was then significantly upregulated probably via the gut-brain axis and further activated the AMPK signaling pathway to improve lipid metabolism including the improvement of lipolysis and fatty acid oxidation and the suppression of lipogenesis. This is the first report of the proposed antiobesity mechanism of FP, thereby providing a comprehensive understanding of nonstarch polysaccharides and obesity.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Linho/química , Leptina/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Saciação/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/genética , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Masculino , Obesidade/metabolismo , Obesidade/psicologia , Extratos Vegetais/química , Polissacarídeos/química , Ratos , Ratos Wistar , Sementes/química , Transdução de Sinais/efeitos dos fármacos
11.
J Agric Food Chem ; 67(26): 7428-7434, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31187991

RESUMO

Protein-polyphenol interactions play a very important role in wine stability assessment, especially in red varieties. Different polysaccharides can influence these interactions by protecting or disrupting charges and are even used as additives to stabilize colloidal solutions. The most common examples are mannoproteins and carboxymethyl cellulose (CMC). In some cases, the mechanisms that are involved in these reactions are not thoroughly understood and can lead to unexpected problems and delayed haze formation after CMC addition to red wines. Small-scale bench trials were conducted in model systems under different pH conditions to monitor the formation of turbidity and protection mechanisms during the interaction of proteins, polyphenols, and polysaccharides. Egg-white protein was chosen as a protein model due to its complex composition, a commercial grape tannin extract was used as polyphenol source, and pectin, glucomannan, mannoprotein, alginate, and CMC were applied as polysaccharides to model various wine conditions. Reactions were monitored in duplicate on a 50 mL scale by spectrophotometry at 860 nm over at least 30 days. Some of the polysaccharides interacted directly with proteins or polyphenols causing precipitation. Other polysaccharides delayed the reaction between proteins and other macromolecules depending on their concentration. The results of these experiments provide important insights into reaction dynamics between macromolecules that are involved in the physical stability of wine.


Assuntos
Carboximetilcelulose Sódica/química , Proteínas do Ovo/química , Extratos Vegetais/química , Polifenóis/química , Polissacarídeos/química , Vinho/análise , Animais , Galinhas , Glicoproteínas de Membrana/química , Taninos/química , Vitis/química
12.
BMC Plant Biol ; 19(1): 271, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31226937

RESUMO

BACKGROUND: The heavy metal cadmium (Cd) accumulates in the environment due to anthropogenic influences. It is unessential and harmful to all life forms. The plant cell wall forms a physical barrier against environmental stress and changes in the cell wall structure have been observed upon Cd exposure. In the current study, changes in the cell wall composition and structure of Medicago sativa stems were investigated after long-term exposure to Cd. Liquid chromatography coupled to mass spectrometry (LC-MS) for quantitative protein analysis was complemented with targeted gene expression analysis and combined with analyses of the cell wall composition. RESULTS: Several proteins determining for the cell wall structure changed in abundance. Structural changes mainly appeared in the composition of pectic polysaccharides and data indicate an increased presence of xylogalacturonan in response to Cd. Although a higher abundance and enzymatic activity of pectin methylesterase was detected, the total pectin methylation was not affected. CONCLUSIONS: An increased abundance of xylogalacturonan might hinder Cd binding in the cell wall due to the methylation of its galacturonic acid backbone. Probably, the exclusion of Cd from the cell wall and apoplast limits the entry of the heavy metal into the symplast and is an important factor during tolerance acquisition.


Assuntos
Cádmio/toxicidade , Parede Celular/química , Medicago sativa/efeitos dos fármacos , Pectinas/química , Poluentes do Solo/toxicidade , Cromatografia Líquida , Perfilação da Expressão Gênica , Ácidos Hexurônicos/metabolismo , Espectrometria de Massas , Monossacarídeos/análise , Proteínas de Plantas/metabolismo , Caules de Planta/química , Polissacarídeos/química , Proteoma
13.
Chem Soc Rev ; 48(15): 4006-4018, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31169838

RESUMO

In the pursuit of developing potent drug molecules, more efficient and straightforward procedures are in high demand. The evergrowing interest in carbohydrate-based therapeutics and vaccines particularly calls for such reliable and universal approaches that assemble oligosaccharides rapidly and stereoselectively. Hereby, we compiled remarkable efforts made in exploring the possibilities of protection-less glycosylation strategies. Pioneering works using organotin reagents or catalysts were introduced first, followed by the organoboron successors that were deemed less toxic and more versatile alternatives. In the meantime, more species such as copper or caesium were also included and supported by a mechanistic rationale. Lastly, we hope to bring further insights into the synthesis of intricate carbohydrate derivatives, achieved with the aid of glycosylation methods discussed herein.


Assuntos
Produtos Biológicos/química , Polissacarídeos/química , Açúcares/química , Produtos Biológicos/síntese química , Glicosilação , Estrutura Molecular , Polissacarídeos/síntese química , Estereoisomerismo , Açúcares/síntese química
14.
Chemistry ; 25(44): 10505-10510, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31173420

RESUMO

Precision cell-selective surface glycan remodeling is of vital importance for modulation of cell surface dynamics, tissue-specific imaging, and immunotherapy, but remains an unsolved challenge. Herein, we report a switchable enzymatic accessibility (SEA) strategy for highly specific editing of carbohydrate moieties of interest on the target cell surface. We demonstrate the blocking of enzyme in the inaccessible state with a metal-organic framework (MOF) cage and instantaneous switching to the accessible state through disassembly of MOF. We further show that this level of SEA regulation enables initial guided enzyme delivery to the target cell surface for subsequent cell-specific glycan remodeling, thus providing a temporally and spatially controlled tool for tuning the glycosylation architectures. Terminal galactose/N-acetylgalactosamine (Gal/GalNAc) remodeling and terminal sialic acid (Sia) desialylation have been precisely achieved on target cells even with other cell lines in close spatial proximity. The SEA protocol features a modular and generically adaptable design, a very short protocol duration (ca. 30 min or shorter), and a very high spatial resolving power (ability to differentiate immediately neighboring cell lines).


Assuntos
Membrana Celular/enzimologia , Polissacarídeos/metabolismo , Acetilgalactosamina/química , Acetilgalactosamina/metabolismo , Aptâmeros de Nucleotídeos/química , Biocatálise , Membrana Celular/química , Ativação Enzimática , Galactose/química , Galactose/metabolismo , Galactose Oxidase/antagonistas & inibidores , Galactose Oxidase/metabolismo , Glicosilação , Células Hep G2 , Humanos , Células MCF-7 , Estruturas Metalorgânicas/química , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Imagem Óptica/métodos , Polissacarídeos/química , Propriedades de Superfície
15.
Planta Med ; 85(13): 1098-1106, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250410

RESUMO

In previous studies, crude Houttuynia cordata polysaccharides showed beneficial effects on acute lung injury in vivo, a syndrome in which anti-complementary activities played an important role. Anti-complementary activity-guided fractionation of H. cordata polysaccharides led to the isolation of two highly branched homogeneous polysaccharides, HC-PS1 and HC-PS3, with a molecular weight of 274 530 and 216 384 Da, respectively. The polysaccharides were purified by chromatography on DEAE-cellulose and Superdex columns. Their structural characterization was performed by IR, GC-MS, methylation, NMR, and SEM analysis. Both HC-PS1 and HC-PS3 are composed of eight types of monosaccharides, including rhamnose, arabinose, mannose, glucose, glucuronic acid, galactose, galacturonic acid, and xylose. The main linkages of the sugar residues in HC-PS1 include terminal Rhap, terminal and 1,5-linked Araf; 1,3,6-linked and 1,4,6-linked Manp; terminal, 1,4-linked, 1,3-linked, 1,3,6-linked and 1,4,6-linked and 1,3,4,6-linked Glcp; and terminal, 1,4-linked and 1,6-linked Galp. The main monosaccharide linkages in HC-PS3 are similar to that of HC-PS1, except the additional 1,3,4-linked Manp and the absence of 1,3,6-linked Glcp. HC-PS1 and HC-PS3 were found to inhibit complement activation through both the classical and alternative pathways with 50% inhibition concentrations of 0.272 - 0.318 mg/mL without interfering with the coagulation system. Preliminary mechanism studies indicated that both HC-PS1 and HC-PS3 inhibited the activation of the complement system by interacting with C2, C4, and C5. The results suggest that HC-PS1 and HC-PS3 could be valuable for the treatment of diseases associated with the excessive activation of the complement system.


Assuntos
Proteínas do Sistema Complemento/efeitos dos fármacos , Houttuynia/química , Cromatografia DEAE-Celulose , Ativação do Complemento/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Polissacarídeos/química , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Carbohydr Polym ; 219: 181-190, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151515

RESUMO

Water-soluble fraction (WSF), CDTA-soluble fraction (CSF), sodium carbonate-soluble fraction (SSF), loosely-bonding KOH-soluble fractions (LKF) and tightly-bonding KOH-soluble fractions (TKF) were sequentially extracted from tomato cell wall polysaccharides. Physicochemical properties and functional bioactivities of these different bonding state tomato fruit polysaccharides (DBTP) were investigated. WSF, CSF and SSF were identified as pectic polysaccharides, while LKF and TKF were identified as hemicellulose. WSF, possessing plenty of galacturonic acids, was considered as an aggregative of linear homogalacturonan with extremely high molecular weight. CSF and SSF, rich in neutral sugars side chains, contained abundant rhamnogalacturonan regions. These polysaccharides exhibited distinct surface morphology and special FTIR spectrums. Thermal analysis manifested that LKF and TKF exhibited higher thermal stability. WSF and SSF showed higher apparent viscosity and elasticity. Assays for functional bioactivities suggested that CSF and SSF displayed stronger antioxidant activities, while CSF, SSF and TKF exhibited higher hypolipidemic activities.


Assuntos
Parede Celular/química , Frutas , Lycopersicon esculentum , Polissacarídeos , Antioxidantes/farmacologia , Elasticidade , Frutas/citologia , Frutas/metabolismo , Hipolipemiantes/farmacologia , Lycopersicon esculentum/citologia , Lycopersicon esculentum/metabolismo , Pectinas/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Solubilidade , Viscosidade
17.
Carbohydr Polym ; 219: 368-377, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151536

RESUMO

A water-soluble polysaccharide was isolated from Tornabea scutellifera and fractionated using a DAEA Sepharose FF column to evaluate its capacity to stimulate natural killer (NK) cells and macrophages. Neutral sugars (71.8-93.5%) constituted the major part of crude polysaccharides and fractions (TSF1 and TSF2) with relatively lower levels of proteins (0.4-20.3%) and uronic acids (0.8-4.9%). The weight average molecular weights (Mw) of 152.7-537.3 × 103 g/mol were measured for isolated polysaccharides. The polysaccharides were composed of glucose (14.4-44.0%), galactose (23.2-43.2%), mannose (28.5-34.2%) and rhamnose (2.6-13.9%) units connected through (1→2)-Galp, (1→2,6)-Galp, (1→4)-Glcp, (1→6)-Glcp, (1→3)-Rhap, (1→2)-Rhap and (1→4)-Manp residues. TSF2 polysaccharide effectively induced RAW264.7 murine macrophages to release nitric oxide, TNF-α, IL-1ß and IL-6, and activated NK cells to produce TNF-α, INF-γ, granzyme-B, perforin, NKG2D and FasL through NF-κB and MAPKs signaling pathways. Overall results suggested that polysaccharides from T. scutellifera could be potent immunostimulatory compounds inducing both macrophages and NK cells.


Assuntos
Ascomicetos/metabolismo , Citocinas/metabolismo , Fatores Imunológicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Óxido Nítrico/metabolismo , Polissacarídeos/farmacologia , Animais , Galactose/química , Glucose/química , Irã (Geográfico) , Células Matadoras Naturais , Manose/química , Camundongos , Polissacarídeos/química , Células RAW 264.7 , Ramnose/química , Ácidos Urônicos/metabolismo
18.
Carbohydr Polym ; 219: 414-422, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151542

RESUMO

The bioconversion of rice straw into ethanol can alleviate the energy crisis and solve problems related to waste treatment. In this study, the effect of soluble polysaccharides (SPs) produced during rice straw saccharification on the formation of extracellular matrices (EMs) by the yeast Saccharomyces cerevisiae was investigated. SPs were characterized by high-performance liquid chromatography (HPLC) and fourier transform infrared spectroscopy (FT-IR). SPs reduced the inhibition of alcohol dehydrogenase activity by phenolic acids (PAs) and regulated the intracellular redox state, resulting in higher ethanol production. The results of flow cytometry, confocal laser scanning microscopy, and atomic force microscopy indicated that PAs changed microbial morphology and caused damage in microbial cell membranes. The protective effect of SPs against cell membrane damage could be attributed to the synthesis of polysaccharide-dependent extracellular matrix, which maintained cellular integrity even under phenolic acid stress. These findings provide new strategies to improve pretreatment and saccharification processes.


Assuntos
Membrana Celular , Matriz Extracelular , Oryza/química , Extratos Vegetais , Polissacarídeos/farmacologia , Saccharomyces cerevisiae , Álcool Desidrogenase/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , China , Etanol/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Fermentação , Hidrólise , Hidroxibenzoatos/toxicidade , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/química , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
19.
Protein Pept Lett ; 26(5): 377-385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31237199

RESUMO

BACKGROUND: Lytic Polysaccharide Monooxygenases (LPMOs) are auxiliary accessory enzymes that act synergistically with cellulases and which are increasingly being used in secondgeneration bioethanol production from biomasses. Several LPMOs have been identified in various filamentous fungi, including Aspergillus fumigatus. However, many LPMOs have not been characterized yet. OBJECTIVE: To report the role of uncharacterized A. fumigatus AfAA9_B LPMO. METHODS: qRT-PCR analysis was employed to analyze the LPMO gene expression profile in different carbon sources. The gene encoding an AfAA9_B (Afu4g07850) was cloned into the vector pET- 28a(+), expressed in the E. coli strain RosettaTM (DE3) pLysS, and purified by a Ni2+-nitrilotriacetic (Ni-NTA) agarose resin. To evaluate the specific LPMO activity, the purified protein peroxidase activity was assessed. The auxiliary LPMO activity was investigated by the synergistic activity in Celluclast 1.5L enzymatic cocktail. RESULTS: LPMO was highly induced in complex biomass like sugarcane bagasse (SEB), Avicel® PH-101, and CM-cellulose. The LPMO gene encoded a protein comprising 250 amino acids, without a CBM domain. After protein purification, the AfAA9_B molecular mass estimated by SDSPAGE was 35 kDa. The purified protein specific peroxidase activity was 8.33 ± 1.9 U g-1. Upon addition to Celluclast 1.5L, Avicel® PH-101 and SEB hydrolysis increased by 18% and 22%, respectively. CONCLUSION: A. fumigatus LPMO is a promising candidate to enhance the currently available enzymatic cocktail and can therefore be used in second-generation ethanol production.


Assuntos
Aspergillus fumigatus/enzimologia , Celulose/química , Proteínas Fúngicas/química , Oxigenases de Função Mista/química , Polissacarídeos/química , Saccharum/química , Biomassa , Escherichia coli/genética , Etanol/química , Proteínas Fúngicas/genética , Hidrólise , Oxirredução , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
20.
Int J Nanomedicine ; 14: 3245-3263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190792

RESUMO

Background: Bacterial resistance to antibiotics is one of the biggest challenges facing medicine today. Anti-adhesive therapy, using inhibitors of bacterial adhesion to epithelial cells, one of the first stages of infection, is a promising approximation in this area. The size, shape, number of sugar and their placement are variables that have to be taken into account in order to develop multivalent systems able to inhibit the bacterial adhesion based on sugar-lectin interaction. Materials and methods: In the present work we report a modular approach for the synthesis of water-soluble 1D-carbon nanotube-sugar nanoconstructs, with the necessary flexibility to allow an efficient sugar-lectin interaction. The method is based on the reaction of aryl diazonium salts generated in situ from aniline-substituted mannose and lactose derivatives with single wall carbon nanotubes (SWCNTs) sidewalls. Results: Two hybrid nanosystems, I-II, exposing mannose or lactose and having a tetraethylene glycol spacer between the sugar and the nanotube sidewall were rapidly assembled and adequately characterized. The sweet nano-objects were then tested for their ability to agglutinate and selectively inhibit the growth of uropathogenic Escherichia coli. These studies have shown that nanosystem I, exposing mannose on the nanotube surface is able to agglutinate and to inhibit the bacterial growth unlike nano-objects II exposing lactose. Conclusion: The results reported constitute a proof of principle in using mannose-coated 1D-carbon nanotubes as antiadhesive drugs that compete for FimH binding and prevent the uropathogenic bacteria from adhering to the urothelial surface.


Assuntos
Escherichia coli/citologia , Nanotubos de Carbono/química , Aglutinação , Aderência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Manose/química , Nanotubos de Carbono/ultraestrutura , Polissacarídeos/síntese química , Polissacarídeos/química , Propriedades de Superfície
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