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1.
Bioresour Technol ; 291: 121839, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31376673

RESUMO

Inorganic salt treatment is a novel, high-yield, and environmentally friendly approach for the production of xylo-oligosaccharides from Sugarcane bagasse with degree of polymerization of 2-5. A xylo-oligosaccharides yield of 53.79% was obtained with 0.1 M MgCl2 treatment at 180 °C/10 min, and 41.89% with 0.1 M FeCl2 treatment at 140 °C/30 min. The xylo-oligosaccharides yield from the co-catalysis of 0.05 M FeCl2 + 0.05 M MgCl2 reached 54.68% (29.34% xylobiose and 20.94% xylotriose) at 140 °C/30 min. The co-catalysis not only effectively improved the xylobiose and xylotriose contents but also increased the total yield of xylo-oligosaccharides under mild reaction conditions. Additionally, the glucose yield observed from the solid residue after inorganic salt treatment was 71.62% by enzymatic hydrolysis. Mg2+ and Fe2+ are essential for good human health without separation from the system, therefore, the inorganic salt treatment can be potentially applied in the co-production of xylo-oligosaccharides and glucose.


Assuntos
Celulose/química , Compostos Ferrosos/química , Cloreto de Magnésio/química , Oligossacarídeos/química , Saccharum/química , Catálise , Glucose/química , Hidrólise , Polimerização
2.
Anticancer Res ; 39(8): 4199-4206, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366506

RESUMO

BACKGROUND/AIM: We previously synthesized a glucose-conjugated chlorin compound e6 (G-chlorin e6), and reported that it has very strong antitumor effects. The aim of the present study was to synthesize acetylated glucose-conjugated chlorin (AcN003HP) and evaluate its antitumor effect and excretion. MATERIALS AND METHODS: To evaluate the antitumor effect of AcN003HP, its IC50 was calculated as well as its accumulation in cancer cells was examined by flow cytometry. Confocal microscopy was used to observe the intracellular localization of AcN003HP. The excretion and antitumor effects of AcN003HP were also evaluated in vivo. RESULTS: AcN003HP showed stronger antitumor effects and accumulation into cancer cells compared to talaporfin sodium, a conventional photosensitizer. AcN003HP was localized in the endoplasmic reticulum. In a xenograft tumor mouse model, AcN003HP showed longer excretion time from the body than G-chlorin e6, and photodynamic therapy using AcN003HP showed very strong antitumor effects. CONCLUSION: The safety, improved controllability, and robust antitumor effects suggest AcN003HP as a good next-generation photosensitizer.


Assuntos
Neoplasias Gastrointestinais/terapia , Glucose/administração & dosagem , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Acetilação/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Retículo Endoplasmático/efeitos dos fármacos , Citometria de Fluxo , Neoplasias Gastrointestinais/patologia , Glucose/síntese química , Glucose/química , Humanos , Camundongos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Porfirinas/administração & dosagem , Porfirinas/síntese química , Porfirinas/química , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Pharm Res ; 36(10): 140, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367876

RESUMO

PURPOSE: In order to overcome the obstacles and side effects of classical chemotherapy, numerous studies have been performed to develop the treatment based on targeted transport of active compounds directly to the site of action. Since tumor cells are featured with intensified glucose metabolism, we set out to develop innovative, glucose-modified PAMAM dendrimer for the delivery of doxorubicin to breast cancer cells. METHODS: PAMAM-dox-glc conjugate was synthesized and characterized by 1H NMR, FT-IR, size and zeta potential measurements. The drug release rate from conjugate was evaluated by dialysis under different pH conditions. The expression level of GLUT family receptors in cells cultured in full and glucose-deprived medium was evaluated by quantitative real-time RT-PCR and flow cytometry. The cytotoxicity of conjugate in presence or absence of GLUT1 inhibitors was determined by MTT assay. RESULTS: We showed that PAMAM-dox-glc conjugate exhibits pH-dependent drug release and increased cytotoxic activity compared to free drug in cells cultured in medium without glucose. Further, we proved that these cells overexpress transporters of GLUT family. The toxic effect of conjugate was eliminated by the application of specific GLUT1 inhibitors. CONCLUSION: Our findings revealed that the glucose moiety plays a crucial role in the recognition of cells with high expression of GLUT receptors. By selectively blocking GLUT1 transporter we showed its importance for the cytotoxic activity of PAMAM-dox-glc conjugate. These results suggest that PAMAM-glucose formulations may constitute an efficient platform for the specific delivery of anticancer drugs to tumor cells overexpressing transporters of GLUT family.


Assuntos
Antineoplásicos/farmacologia , Dendrímeros/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Transportador de Glucose Tipo 1/metabolismo , Glucose/efeitos adversos , Antineoplásicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Regulação da Expressão Gênica , Glucose/química , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Tamanho da Partícula
4.
J Agric Food Chem ; 67(35): 9840-9850, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31424924

RESUMO

In the present study, methanolysis of poplar biomass was conducted for the selective transformation of hemicellulose and lignin, which leads to methyl glycosides (mainly C5 glycosides) and lignin fragments in the liquefied products that can be separated according to their difference in hydrophilicity. The distribution of methyl glycosides and delignification was dependent on the presence of acid catalysts and reaction temperatures. The obtained lignin fraction was separated into solid lignin fragments and liquid lignin oil according to their molecular weight distribution. Subsequently, directional conversion of methyl C5 glycosides into methyl levulinate was performed with dimethoxymethane/methanol as the cosolvent. A yield of 12-30% of methyl levulinate yield (based on the methyl glycoside) was achieved under these conditions. The remaining cellulose-rich substrate showed enhanced susceptibility to enzymatic hydrolysis, resulting in a yield of glucose of above 70%. Overall, the described strategy shows practical implications for the effective valorization of biomass.


Assuntos
Fracionamento Químico/métodos , Glucose/isolamento & purificação , Ácidos Levulínicos/isolamento & purificação , Metanol/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Populus/química , Madeira/química , Catálise , Celulose/química , Celulose/isolamento & purificação , Glucose/química , Ácidos Levulínicos/química , Lignina/química , Lignina/isolamento & purificação , Fenóis/química , Extratos Vegetais/química
5.
Chemistry ; 25(51): 11940-11944, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31317582

RESUMO

In addition to superior enzyme-mimicking abilities, nanozymes also have intrinsic physicochemical properties. Integrating the enzyme-like activities and tunable physicochemical properties into a single nanoparticle is a promising strategy for versatile nanozyme design and application. Herein, a composite nanozyme in which Au nanoparticles are encapsulated by Au nanoclusters (AuNP@AuNCs) is presented. By integrating the peroxidase-mimicking ability of fluorescent Au NCs with the glucose oxidase-like activity of Au NPs, the composite nanozyme realized cascade assay of glucose without the aid of external indicators. Compared to traditional multistep colorimetric methods, the analytical process was highly simplified by using the self-responsive nanozyme. This synthetic strategy provided valuable insights into exploring talented nanozymes for sensing diverse targets.


Assuntos
Glucose Oxidase/química , Glucose/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Peroxidase/química , Colorimetria/métodos , Glucose/química , Glucose Oxidase/metabolismo
6.
Food Chem ; 300: 125178, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326677

RESUMO

In this work, a sensitive and stable ZrO2-Cu(I) nanosphere mesoporous material modified non-enzymatic glucose sensor has been developed through simple, low cost chemistry. ZrO2-Cu(I) material was obtained by controlled co-precipitation method under ultra dilution conditions. Cyclic voltammetric tests were performed in order to evaluate the electrocatalytic activity ZrO2-Cu(I) modified electrode. The modified electrode showed high sensitivity, wide linear range and very low detection limit of 0.25 mM, this indicates that the modified sensor is competent with that reported earlier. Spherical morphology of the active material, alkaline environment and presence of +1 copper have significantly enhanced the electro-catalytic oxidation of glucose on carbon paste platform. Also, the fabricated electrode showed excellent anti-interference nature. Electro-catalytic oxidation of glucose was demonstrated in real raw unpurified orange juice, this shows the selective electrocatalytic activity of the ZrO2-Cu(I) nanosphere material towards glucose even in the presence of interferrants.


Assuntos
Citrus sinensis/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Glucose/análise , Carbono/química , Catálise , Cobre/química , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Glucose/química , Limite de Detecção , Nanosferas/química , Oxirredução , Zircônio/química
7.
Bioengineered ; 10(1): 335-344, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31322471

RESUMO

Selenium-enriched yeast can transform toxic inorganic selenium into absorbable organic selenium, which is of great significance for human health and pharmaceutical industry. A yeast Rhodotorula glutinis X-20 we obtained before has good selenium-enriched ability, but its selenium content is still low for industrial application. In this study, strategies of process optimization and transport regulation of selenium were thus employed to further improve the cell growth and selenium enrichment. Through engineering phosphate transporters from Saccharomyces cerevisiae into R. glutinis X-20, the selenium content was increased by 21.1%. Through using mixed carbon culture (20 g L-1, glycerol: glucose 3:7), both biomass and selenium content were finally increased to 5.3 g L-1 and 5349.6 µg g-1 (cell dry weight, DWC), which were 1.14 folds and 6.77 folds compared to their original values, respectively. Our results indicate that high selenium-enrichment ability and biomass production can be achieved through combining process optimization and regulation of selenium transport.


Assuntos
Engenharia Metabólica/métodos , Fosfatos/metabolismo , Rhodotorula/genética , Saccharomyces cerevisiae/genética , Selênio/metabolismo , Transgenes , Transporte Biológico , Biomassa , Meios de Cultura/química , Meios de Cultura/farmacologia , Fermentação , Expressão Gênica , Glucose/química , Glucose/metabolismo , Glicerol/química , Glicerol/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Simportadores de Próton-Fosfato/genética , Simportadores de Próton-Fosfato/metabolismo , Rhodotorula/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo
8.
J Agric Food Chem ; 67(32): 9050-9059, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31339697

RESUMO

The control of 2,3-dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one (DDMP) formation in the Maillard reaction is important to improve the thermally treated food quality as a result of its intense bitterness and potential toxicity. In this work, phenolic acids, such as gallic, protocatechuic, caffeic, and ferulic acids, were applied to modulate DDMP formation in a microaqueous glucose-proline model. The formation of DDMP was inhibited at low concentrations (from 0.1 to 5.0 mM) while enhanced at 10.0 mM gallic, protocatechuic, and caffeic acids. Ferulic acid always inhibited DDMP formation as a result of the absence of catechol groups on its benzene ring. The result indicated that the control of DDMP formation depended upon the concentration and chemical structures of phenolic acids, such as the number of hydroxyl groups. Further studies indicated that the hydroxyl distribution of phenolic acids regulated the peroxide formation in the model reaction system and further changed the development of the oxidation reaction, which affected the degradation of glucose via caramel or Maillard reaction, Amadori rearrangement product oxidation, and 1-deoxyglucosone degradation to form the intermediates.


Assuntos
Glucose/química , Hidroxibenzoatos/química , Prolina/química , Pironas/química , Reação de Maillard , Modelos Químicos , Oxirredução
9.
J Agric Food Chem ; 67(28): 7961-7967, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31260294

RESUMO

Food-derived glycated phospholipids is potentially hazardous to human health. However, there are few studies on the effects of lipids on the formation of glycated phospholipids. In this work, two model systems were established: (1) a model system including 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (PE), glucose, and Fenton reagent and (2) a model system including PE, glucose, and five kind of vegetable oils. The contents of carboxymethyl-PE, carboxyethyl-PE, Amadori-PE, hydroxyl radical (OH•), glyoxal, and methylglyoxal were determined with high-performance liquid chromatography mass spectrometry. The results of the first model system showed that OH• oxidized glucose to produce glyoxal and methylglyoxal, which then reacted with PE to form carboxymethyl-PE and carboxyethyl-PE. OH• also oxidized Amadori-PE to form carboxymethyl-PE. The results of the second model system showed that vegetable oils with higher number of moles of carbon-carbon unsaturated double bond in vegetable oil per kilogram could produce more OH•, which promote the formation of carboxymethyl-PE and carboxyethyl-PE by oxidizing glucose and oil. We elucidated the effects of oils on the formation of glycated phospholipids in terms of OH• and intermediates. This work will contribute to better understanding the formation mechanism of glycated phospholipids with oil.


Assuntos
Radical Hidroxila/química , Lipídeos/química , Fosfolipídeos/química , Cromatografia Líquida de Alta Pressão , Glucose/química , Glicosilação , Glioxal/química , Reação de Maillard , Espectrometria de Massas , Modelos Químicos , Oxirredução , Aldeído Pirúvico/química
10.
Food Chem ; 298: 124981, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260993

RESUMO

Development of an effective sensor for sensing glucose in commercially available "sugar free" food products is important as people are becoming diabetic health conscious. Although multi-walled carbon nanotubes (MWCNTs) possess interesting electrical properties, their hydrophobic nature limits their applications. Their hydrophilicity can be improved through modification. In the present study, Inulin, that was isolated from Allium sativum L. using hot water diffusion and incorporated with titanium dioxide (TiO2), was used for the modification of MWCNTs. The as-synthesized MWCNT-Inulin-TiO2 bio-nanocomposite immobilized with glucose oxidase (GOx) was incorporated into the carbon paste matrix and was utilized for the sensing of glucose in food products. Differential pulse voltammetric studies revealed that the fabricated electrode demonstrated good linear range (1.6 nM to 1 µM) and was sensitive to nanomolar concentrations of glucose with a very low limit of detection up to 0.82 nM and exhibited a long term stability of 150 days.


Assuntos
Eletrodos , Análise de Alimentos/métodos , Glucose Oxidase/química , Glucose/análise , Nanocompostos/química , Enzimas Imobilizadas/química , Análise de Alimentos/instrumentação , Alho/química , Glucose/química , Inulina/química , Limite de Detecção , Nanotubos de Carbono/química , Sensibilidade e Especificidade , Titânio/química
11.
Food Chem ; 295: 120-128, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174740

RESUMO

This research investigated the effects of commonly practiced thermal treatments (simulated pasteurization, retort sterilization and UHT sterilization) on peanut protein isolate (PPI)-glucose solution. Results showed that thermal treatment on PPI-glucose solution from mild to drastic conditions would lead to a more ordered and compact protein structure, greater extent of Maillard reaction, higher degree of graft, stronger in vitro antioxidant activities, but decrease in vitro digestion especially lower degree of hydrolysis in two-step enzymolysis by pepsin and then pancreatin. Compared with the unheated PPI-glucose solution, the Td values of ones autoclaved at 121 °C for 30 min and 45 min increased by 5% and 12%, and the ΔH of all the heated samples was lower than the unheated one. The present study indicated that retort sterilization or UHT sterilization treatment could be favourable in producing a beverage containing PPI and glucose with proper digestibility and post-digestion antioxidant activities.


Assuntos
Arachis/metabolismo , Glucose/química , Proteínas de Plantas/metabolismo , Antioxidantes/química , Varredura Diferencial de Calorimetria , Dicroísmo Circular , Hidrólise , Reação de Maillard , Pasteurização , Pepsina A/metabolismo , Proteínas de Plantas/química , Estrutura Terciária de Proteína , Temperatura Ambiente
12.
Food Chem ; 295: 165-171, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174746

RESUMO

Deep eutectic solvents (DES) and aqueous glycerol were proposed as green alternatives to conventional solvents for the extraction of polyphenols from grapefruit peels. In order to increase the extraction kinetics and yields of polyphenols, high voltage electrical discharges (HVED) were used as a pre-treatment technology (energy varied between 7.27 and 218 kJ/kg). Results showed that the HVED energy input can be reduced, when the subsequent solid-liquid extraction was performed in 20% (w/v) aqueous glycerol or in DES (lactic acid: glucose) instead of water. The addition of glycerol has reduced the energy of the pre-treatment by 6 times. The same diffusivity of polyphenols (4 × 10-11 m2/s) was obtained in water from HVED pre-treated peels at 218 kJ/kg and in aqueous glycerol from pre-treated peels at 36 kJ/kg. The solubility of naringin, the main flavonoid compound of grapefruit peels in the solvents, was investigated through a theoretical modelling of its Hansen solubility parameters.


Assuntos
Citrus paradisi/química , Glicerol/química , Polifenóis/isolamento & purificação , Solventes/química , Cromatografia Líquida de Alta Pressão , Citrus paradisi/metabolismo , Eletricidade , Flavanonas/química , Flavonoides/química , Glucose/química , Ácido Láctico/química , Extração Líquido-Líquido , Polifenóis/análise , Solubilidade , Água/química
13.
Plant Physiol Biochem ; 141: 477-486, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31252253

RESUMO

The induction of leaf injuries, including leaf chlorosis and epinasty, by continuous light in tomato plants is one of the most interesting and mysterious phenomena regarding plant interactions with light, the mechanism of which has not yet been revealed. To gain further insights into this particular response of tomato plants, we cultivated tomato seedlings (Solanum lycopersicum cv. Momotaro) for 14 days under continuous light with different ratios of red and blue light and compared their performance to those grown under continuous or 14/10-h photoperiodic white light using novel methods to quantitatively evaluate the level of leaf chlorosis and epinasty. Continuous monochromatic blue light induced severe chlorosis but almost completely alleviated epinasty in tomato leaf. In contrast, continuous monochromatic red light caused a lower level of leaf chlorosis but very severe epinasty. The combination of red and blue light at different ratios significantly reduced both leaf chlorosis and epinasty under continuous light condition. Carbohydrate contents showed no correlation with leaf chlorosis, while glucose and fructose contents showed correlations with the petiole and leaflet curvatures. Histochemical staining with 3,3'-diaminobenzidine and nitro blue tetrazodium chloride also did not reveal any significant buildup of hydrogen peroxide and superoxide anion in monochromatic blue light treatment. Taken together, these results suggest that chlorosis and epinasty are two distinctive leaf injuries caused by continuous light that may follow very different mechanisms, and an overaccumulation of carbohydrates in the leaf may not be the main cause of continuous light-induced leaf chlorosis in tomato.


Assuntos
Luz , Lycopersicon esculentum/efeitos da radiação , Folhas de Planta/efeitos da radiação , 3,3'-Diaminobenzidina/química , Anemia Hipocrômica/metabolismo , Carboidratos/química , Cor , Frutose/química , Glucose/química , Peróxido de Hidrogênio/química , Lycopersicon esculentum/crescimento & desenvolvimento , Oxigênio/química , Fotoquímica , Fotoperíodo , Fotossíntese , Doenças das Plantas , Proteínas de Plantas/metabolismo , Plântula/metabolismo , Sais de Tetrazólio/química
14.
J Microbiol Biotechnol ; 29(6): 905-912, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31154746

RESUMO

Bioethanol has attracted much attention in recent decades as a sustainable and environmentally friendly alternative energy source. In this study, we compared the production of bioethanol by Candida molischiana and Saccharomyces cerevisiae at different initial concentrations of cellobiose and glucose. The results showed that C. molischiana can utilize both glucose and cellobiose, whereas S. cerevisiae can only utilize glucose. The ethanol yields were 43-51% from different initial concentrations of carbon source. In addition, different concentrations of microcrystalline cellulose (Avicel) were directly converted to ethanol by a combination of Trichoderma reesei and two yeasts. Cellulose was first hydrolyzed by a fully enzymatic saccharification process using T. reesei cellulases, and the reducing sugars and glucose produced during the process were further used as carbon source for bioethanol production by C. molischiana or S. cerevisiae. Sequential culture of T. reesei and two yeasts revealed that C. molischiana was more efficient for bioconversion of sugars to ethanol than S. cerevisiae. When 20 g/l Avicel was used as a carbon source, the maximum reducing sugar, glucose, and ethanol yields were 42%, 26%, and 20%, respectively. The maximum concentrations of reducing sugar, glucose, and ethanol were 10.9, 8.57, and 5.95 g/l, respectively, at 120 h by the combination of T. reesei and C. molischiana from 50 g/l Avicel.


Assuntos
Biocombustíveis , Candida/metabolismo , Celobiose/metabolismo , Celulose/metabolismo , Etanol/metabolismo , Glucose/metabolismo , Saccharomyces cerevisiae/metabolismo , Candida/crescimento & desenvolvimento , Celobiose/química , Celulase/metabolismo , Celulose/química , Proteínas Fúngicas/metabolismo , Glucose/química , Hidrólise , Saccharomyces cerevisiae/crescimento & desenvolvimento , Açúcares/metabolismo , Trichoderma/crescimento & desenvolvimento , Trichoderma/metabolismo
15.
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
16.
Nanoscale ; 11(18): 9163-9175, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31038150

RESUMO

Diabetes is a chronic metabolic disorder disease characterized by high blood glucose levels and has become one of the most serious threats to human health. In recent decades, a number of insulin delivery systems, including bulk gels, nanogels, and polymeric micelles, have been developed for the treatment of diabetes. Herein, a kind of glucose and H2O2 dual-responsive polymeric nanogel was designed for enhanced glucose-responsive insulin delivery. The polymeric nanogels composed of poly(ethylene glycol) and poly(cyclic phenylboronic ester) (glucose and H2O2 dual-sensitive groups) were synthesized by a one-pot thiol-ene click chemistry approach. The nanogels displayed glucose-responsive release of insulin and the release rate could be promoted by the incorporation of glucose oxidase (GOx), which generated H2O2 at high glucose levels and H2O2 further oxidizes and hydrolyzes the phenylboronic ester group. The nanogels have characteristics of long blood circulation time, a fast response to glucose, and excellent biocompatibility. Moreover, subcutaneous delivery of insulin to diabetic mice with the insulin/GOx-loaded nanogels presented an effective hypoglycemic effect compared to that of injection of insulin or insulin-loaded nanogels. This kind of nanogel would be a promising candidate for the delivery of insulin in the future.


Assuntos
Glucose Oxidase/química , Glucose/metabolismo , Peróxido de Hidrogênio/metabolismo , Hipoglicemiantes/metabolismo , Insulina/metabolismo , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Química Click , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose/química , Glucose Oxidase/metabolismo , Teste de Tolerância a Glucose , Peróxido de Hidrogênio/química , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Insulina/química , Insulina/uso terapêutico , Camundongos , Células NIH 3T3 , Polietilenoglicóis/toxicidade , Polietilenoimina/toxicidade
17.
J Agric Food Chem ; 67(20): 5754-5763, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31045365

RESUMO

Recently, although ginseng ( Panax ginseng C. A. Meyer) and its main component saponins (ginsenosides) have been reported to exert protective effects on cisplatin (CDDP)-induced acute kidney injury (AKI), the beneficial activities of non-saponin on CDDP-induced AKI is little known. This research was designed to explore the protective effect and underlying mechanism of arginyl-fructosyl-glucose (AFG), a major and representative non-saponin component generated during the process of red ginseng, on CDDP-caused AKI. AFG at doses of 40 and 80 mg/kg remarkably reversed CDDP-induced renal dysfunction, accompanied by the decreased levels of serum creatinine and blood urea nitrogen. Interestingly, all of oxidative stress indices were ameliorated after pretreatment with AFG continuously for 10 days. Importantly, AFG relieved CDDP-induced inflammation and apoptosis in part by mitigating the cascade initiation steps of nuclear factor κB signals and regulating the participation of the phosphatidylinositol 3-kinase/protein kinase B signal pathway. In conclusion, these results clearly provide strong rationale for the development of AFG to prevent CDDP-induced AKI.


Assuntos
Lesão Renal Aguda/tratamento farmacológico , Arginina/análogos & derivados , Cisplatino/efeitos adversos , Medicamentos de Ervas Chinesas/administração & dosagem , Glucose/administração & dosagem , Glicina/análogos & derivados , NF-kappa B/metabolismo , Panax/química , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Arginina/administração & dosagem , Arginina/química , Creatinina/metabolismo , Medicamentos de Ervas Chinesas/química , Glucose/química , Glicina/administração & dosagem , Glicina/química , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Reação de Maillard , Masculino , Camundongos Endogâmicos ICR , NF-kappa B/genética , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos
18.
Chemistry ; 25(39): 9272-9279, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31099933

RESUMO

There is a growing interest in the preparation of polyfluorinated carbohydrates. A limited number of fluorohexopyranosides have been used in biological investigations because of the synthetic challenge they present. Hence, we report the synthesis of fluorinated homodimer, fluorodisaccharides, C-terminal fluoroglycopeptides, lipoic acid fluoroglycoconjugate and trifluoroallopyranoside derivatives functionalized at C-6. Our strategy uses levoglucosan as inexpensive starting material and facilitates an approach to complex carbohydrate analogues with multiple C-F bonds. The challenge of our synthetic route centered around an efficient preparation of crucial 1,6-anhydro-2,4-dideoxy-difluoroglucopyranose and focused on achieving a difficult glycosylation of the trifluoroallopyranose donor. The results clearly highlight challenges related to the preparation of polyhalogenated complex organic molecules and pave the way to access novel medically relevant tools.


Assuntos
Carboidratos/química , Glucose/química , Dissacarídeos/química , Fluoretação , Glucose/análogos & derivados , Glicoconjugados/química , Piranos/química , Estereoisomerismo
19.
Food Chem ; 294: 203-208, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126454

RESUMO

To investigate the potential of terahertz spectroscopy to monitor and quantify starch in plants, terahertz spectra (3.0-13.5 THz) of mung bean plants 1-7 days after germination were examined and compared to those of starch and its constituent saccharides (standard reagents). Day 1 seedlings showed similar spectral features with standard starch, and absorption peaks gradually disappeared in the subsequent 6 day growth period. To interpret this result and identify useful peaks for starch quantification, standard starch and day 1 seedlings were hydrolyzed by α-amylase in vitro. Since both standard starch and seedlings showed that absorption peak at 9.0 THz disappeared after amylase hydrolysis, this peak is sensitive to changes in starch. Additionally, intensity of this peak was correlated with starch content as quantified by chemical analysis (r = 0.98). Our results indicate terahertz spectra of seedlings can provide an identifiable peak that is attributed to starch and not affected by the constituent saccharides.


Assuntos
Amido/química , Espectroscopia Terahertz , Vigna/química , Germinação , Glucose/química , Hidrólise , Plântula/química , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Vigna/crescimento & desenvolvimento , Vigna/metabolismo , alfa-Amilases/metabolismo
20.
J Agric Food Chem ; 67(22): 6350-6358, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31083944

RESUMO

α-Dicarbonyls are reactive intermediates formed during Maillard reactions and carbohydrate degradation. The formation of seven α-dicarbonyls was characterized in solutions containing dairy related carbohydrates (galactose, glucose, lactose, and galacto-oligosaccharides (GOS)) during incubations at 40 and 50 °C with and without Nα-acetyl-l-lysine at pH 6.8 for up to 2 months. The concentrations of α-dicarbonyls in samples of monosaccharides with Nα-acetyl-l-lysine were found to be 3-deoxyglucosone (3-DG) > 3-deoxygalactosone (3-DGal) > glyoxal > glucosone, galactosone > methylglyoxal > diacetyl. The presence of Nα-acetyl-l-lysine resulted in up to 100-fold higher concentrations of C6 α-dicarbonyls but lesser formation of glyoxal in the monosaccharide-containing models compared to what was observed in the absence of Nα-acetyl-l-lysine. Galactose incubated with Nα-acetyl-l-lysine generated the highest concentrations of 3-DGal (up to 130 µM), glyoxal (up to 100 µM), and methylglyoxal (up to 9 µM) compared to the other carbohydrates during incubation. Surprisingly, 3-DG (1500 µM) and 3-DGal (80 µM) were formed at levels of 2 orders of magnitude higher in solutions of GOS in the absence of Nα-acetyl-l-lysine as compared to the other carbohydrates at 40 °C, while GOS generated the lowest levels of glyoxal. GOS are widely used as an ingredient in various types of foods products, and it is therefore of importance to consider the risk of generating high levels of the reactive C6 α-dicarbonyl, 3-DG, in these types of products. This study contributes to the understanding of major α-dicarbonyl formation as affected by the presence of primary amines in GOS-, lactose-, and galactose-containing solutions under moderate heating in liquid foods.


Assuntos
Galactose/química , Glucose/química , Glioxal/química , Lactose/química , Lisina/química , Leite/química , Oligossacarídeos/química , Animais , Bovinos , Laticínios/análise , Temperatura Alta , Reação de Maillard , Oxirredução , Aldeído Pirúvico/química
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