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1.
Chin J Nat Med ; 18(3): 219-225, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32245592

RESUMO

The rapid detection of pathogenic bacteria is vital for the prevention of outbreaks of infectious diseases, including infections by the common foodborne bacteria E.coli and Salmonella Carbohydrate microarrays have been developed as a powerful method to investigate carbohydrate-protein interaction with only very small amounts of glycans, which show great potential for detect the carbohydrate mediated interaction with pathogens. Here, different mannose-coated microarrays were constructed and tested with E.coli (K-12 and BL-21) and Salmonella enterica strains (ATCC9184 and ATCC31685) exhibiting different mannose binding affinities. The optimized carbohydrate microarray was then applied to test the binding of 12 Salmonella enterica and 9 E.coli isolates from local patients for the first time and showed strong binding with certain serovars or subtypes. The results showed that microarray probed with the single mannose structure is not enough for the detection of bacteria with various serovars or subtypes, which contain a high degree of allelic variation in adhesin. We suggest that a complex carbohydrate microarray containing different glycan conformation may be needed for detection of different bacteria isolates.


Assuntos
Carboidratos/química , Escherichia coli/isolamento & purificação , Análise em Microsséries/métodos , Salmonella enterica/isolamento & purificação , Adesinas Bacterianas/química , Contaminação de Alimentos , Microbiologia de Alimentos , Humanos , Manose/química , Polissacarídeos/química
2.
J Food Sci ; 85(2): 249-259, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32031261

RESUMO

In some tropical countries, people are suffering from both undernourishment and noncommunicable disorders, such as overweight/obesity. Starchy tropical fruits and tubers are of particular interest for their carbohydrate content and for the micronutrients they provide. The present study summarizes the content in carbohydrate, phenolics, carotenoids, and vitamin C, as well as the antioxidant activity of a wide range of tropical fruits and tubers. The energy content of fruits and tubers studied is in the range of 1,200 to 1,800 kJ/100 g of dry weight. They are thus important staple foods and, due to their diversity and seasonality, they can provide energy all year long by alternating the resources in the human diet. Starchy fruit and tuber crops have antiobesity properties as they are bulky, rich in moisture, and contain less than 2% of fat. Noncolored fruit and tubers provide total phenolics at about 20 to 140 mEq/100 g fresh weight. They thus have a high antioxidant capacity, as related to their total phenolic content but also to the presence of carotenoids, such as lutein, mostly in Dioscorea bulbifera and cocoyam. Yellow and orange-fleshed varieties contain more total phenolics and also more provitamin A carotenoids than noncolored fleshed ones. The contents in total phenolic and carotenoid greatly vary with the species and variety. The influence of pre and postharvest conditions on micronutrient content is discussed. Further studies on new processing methods are needed to maximize polyphenols and carotenoids retention in the foods and increase the bioaccessibility of these compounds. PRACTICAL APPLICATION: This paper provides information on the nutritional quality of starchy tropical fruits and tubers. Nutritional quality is studied from the point of view of providing energy and bioactive compounds. The paper aims to promote the use of local resources in tropical areas, which could ultimately limit the adverse effects of food globalization on noncommunicable disorders. It could also lead to tropical countries being less dependent on food imports.


Assuntos
Carboidratos/química , Frutas/química , Extratos Vegetais/química , Tubérculos/química , Frutas/crescimento & desenvolvimento , Valor Nutritivo , Tubérculos/crescimento & desenvolvimento , Amido/química
3.
Food Chem ; 312: 125904, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901701

RESUMO

This study investigated sucrose catabolism during cold-induced sweetening (CIS) and its impact on the quality of sweet potato chips of cultivars with varied levels of tolerance to cold during storage at 6 and 13 °C. In contrast to cultivar Beauregard, cultivar BRS Rubissol and BRS Cuia were cold-sensitive exhibiting intense symptoms of chilling injury at 6 °C. CIS in the sensitive cultivars BRS Rubissol and BRS Cuia was characterized by low accumulation of reducing sugar (RS), high non-reducing sugars content, low invertase activity and high sucrose synthase (SuSy) activity. In the tolerant cultivar Beauregard, the high content of RS was due to high invertases activity. In the three cultivars, the darkening of chips was more influenced by the non-reducing sugars, instead of RS. Our results suggest that SuSy was induced by cold stress in cold-sensitive cultivar, but did not contribute to the CIS in sweet potato.


Assuntos
Edulcorantes/química , Metabolismo dos Carboidratos , Carboidratos/química , Temperatura Baixa , Glucosiltransferases , Ipomoea batatas/metabolismo , Edulcorantes/metabolismo , Paladar , beta-Frutofuranosidase/metabolismo
4.
Food Chem ; 313: 126121, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31923870

RESUMO

This study aimed to evaluate the influences of high-intensity ultrasound on the physiochemical properties of kiwifruit juice. Results reported high-intensity ultrasound processing significantly enhanced the color attributes, cloudiness, and sugars of kiwifruit juice. Further, the shear stress, apparent viscosity, storage and loss modulus was increased with the rise of processing time. However, a significant degradation in the nanostructure of water-soluble pectin and suspended particles in ultrasound treated kiwifruit juice was observed. In addition, ultrasound processing resulted in the rupture of cell wall causing the dispersion of the intracellular components into juice while higher damage in the cellular structure was observed by increasing the processing time. These structural changes reveal the physical mechanism of ultrasound in improving the rheological properties, color attributes, cloudiness, and water-soluble pectin of kiwifruit juice. Altogether these findings suggest that high-intensity ultrasound has an enormous potential to improve the physical properties of kiwifruit juice.


Assuntos
Actinidia/metabolismo , Carboidratos/química , Sucos de Frutas e Vegetais/análise , Pectinas/química , Sonicação , Cor , Tamanho da Partícula , Reologia , Resistência ao Cisalhamento , Viscosidade
5.
J Food Sci ; 85(2): 364-373, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976552

RESUMO

Sea buckthorn (Hippophaë rhamnoides) is increasingly cultivated to produce raw materials for food and nutraceuticals. There is little knowledge on composition of sea buckthorn leaves (SBLs) and the key factors influencing the composition. This research aims to unravel the metabolic profile of SBLs and the effects of cultivar, location and stage of growth, and climatic conditions on the metabolic profile of SBLs. Leaves of two sea buckthorn cultivars grown in the south and north of Finland during two consecutive growth seasons were studied using untargeted nuclear magnetic resonance (NMR) metabolomics. The highest variance in the metabolic profile was linked to the growth stage, wherein leaves from the first 7 weeks of harvest were characterized with higher abundance of polyphenols, while relatively higher abundance of carbohydrates and sugars was observed in the later weeks. The growth location attributed for the second highest variation, wherein the north-south comparison identified fatty acids and sugars as discriminatory metabolites, and the potential association of metabolome to natural abiotic stressors was revealed. An inverse correlation between carbohydrate/sugar content as well as fatty acids of higher carbon chain length with the temperature variables was evident. The supervised chemometric models with high sensitivity and specificity classified and predicted the samples based on growth stage and location, and cultivar. Nontargeted NMR-metabolomics revealed the metabolic profile of SBLs and their variation associated with various biotic and abiotic factors. Cultivar and growth stage are key factors to consider when harvesting SBLs for use in food and nutraceuticals. PRACTICAL APPLICATION: Globally, sea buckthorn cultivation has been rapidly increasing due to the known health-promoting benefits of the berries and leaves of the plant. The current research obtained new comprehensive information on the compositional profile of sea buckthorn leaves as well as the impact of major contributory factors, such as cultivars, the advancement of growth stage, geographical location, and weather parameters. The findings of this research provide new knowledge and guidance for plant breeding, cultivation and commercial utilization of sea buckthorn leaves as raw materials for food, feed, and nutraceuticals.


Assuntos
Hippophae/química , Folhas de Planta/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Carboidratos/química , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Finlândia , Frutas/química , Hippophae/crescimento & desenvolvimento , Hippophae/metabolismo , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Metabolômica , Folhas de Planta/química , Estações do Ano
6.
Pharm Res ; 37(3): 33, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31942659

RESUMO

PURPOSE: Dissolvable microneedle arrays (MNAs) can be used to realize enhanced transdermal and intradermal drug delivery. Dissolvable MNAs are fabricated from biocompatible and water-soluble base polymers, and the biocargo to be delivered is integrated with the base polymer when forming the MNAs. The base polymer is selected to provide mechanical strength, desired dissolution characteristics, and compatibility with the biocargo. However, to satisfy regulatory requirements and be utilized in clinical applications, cytotoxicity of the base polymers should also be thoroughly characterized. This study systematically investigated the cytotoxicity of several important carbohydrate-based base polymers used for production of MNAs, including carboxymethyl cellulose (CMC), maltodextrin (MD), trehalose (Treh), glucose (Gluc), and hyaluronic acid (HA). METHODS: Each material was evaluated using in vitro cell-culture methods on relevant mouse and human cells, including MPEK-BL6 mouse keratinocytes, NIH-3T3 mouse fibroblasts, HaCaT human keratinocytes, and NHDF human fibroblasts. A common laboratory cell line, human embryonic kidney cells HEK-293, was also used to allow comparisons to various cytotoxicity studies in the literature. Dissolvable MNA materials were evaluated at concentrations ranging from 3 mg/mL to 80 mg/mL. RESULTS: Qualitative and quantitative analyses of cytotoxicity were performed using optical microscopy, confocal fluorescence microscopy, and flow cytometry-based assays for cell morphology, viability, necrosis and apoptosis. Results from different methods consistently demonstrated negligible in vitro cytotoxicity of carboxymethyl cellulose, maltodextrin, trehalose and hyaluronic acid. Glucose was observed to be toxic to cells at concentrations higher than 50 mg/mL. CONCLUSIONS: It is concluded that CMC, MD, Treh, HA, and glucose (at low concentrations) do not pose challenges in terms of cytotoxicity, and thus, are good candidates as MNA materials for creating clinically-relevant and well-tolerated biodissolvable MNAs.


Assuntos
Carboidratos/química , Carboidratos/toxicidade , Polímeros/química , Animais , Apoptose/efeitos dos fármacos , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/toxicidade , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Glucose/química , Glucose/toxicidade , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/toxicidade , Camundongos , Microinjeções , Agulhas , Preparações Farmacêuticas/química , Polissacarídeos/química , Polissacarídeos/toxicidade , Solubilidade , Trealose/química , Trealose/toxicidade
7.
Food Microbiol ; 87: 103392, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948633

RESUMO

Genetic diversity and metabolic properties of Lactococcus lactis subsp. lactis were explored using phylogenetic, pan-genomic and metatranscriptomic analysis. The genomes, used in the current study, were available and downloaded from the GenBank which were primarily related with microorganisms isolated from dairy products and secondarily from other foodstuffs. To study the genetic diversity of the microorganism, various bioinformatics tools were employed such as average nucleotide identity, digital DNA-DNA hybridization, phylogenetic analysis, clusters of orthologous groups analysis, KEGG orthology analysis and pan-genomic analysis. The results showed that Lc. lactis subsp. lactis strains cannot be sufficiently separated into phylogenetic lineages based on the 16S rRNA gene sequences and core genome-based phylogenetic analysis was more appropriate. Pan-genomic analysis of the strains indicated that the core, accessory and unique genome comprised of 1036, 3146 and 1296 genes, respectively. Considering the results of pan-genomic and KEGG orthology analyses, the metabolic network of Lc. lactis subsp. lactis was rebuild regarding its carbohydrates' metabolic capabilities. Based on the metatranscriptomic data during the ripening of the Swiss-type Maasdam cheese at 20 °C and 5 °C, it was shown that the microorganism performed mixed acid fermentation producing lactate, formate, acetate, ethanol and 2,3-butanediol. Mixed acid fermentation was more pronounced at higher ripening temperatures. At lower ripening temperatures, the genes involved in mixed acid fermentation were repressed while lactate production remained unaffected resembling to a homolactic fermentation. Comparative genomics and metatranscriptomic analysis are powerful tools to gain knowledge on the genomic diversity of the lactic acid bacteria used as starter cultures as well as on the metabolic activities occurring in fermented dairy products.


Assuntos
Metabolismo dos Carboidratos , Queijo/microbiologia , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Carboidratos/química , Fermentação , Microbiologia de Alimentos , Variação Genética , Genômica , Lactococcus lactis/classificação , Lactococcus lactis/isolamento & purificação , Filogenia
8.
Chemosphere ; 242: 125080, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675581

RESUMO

Lignocellulosic ethanol has been proposed as a green alternative to fossil fuels for many decades. However, commercialization of lignocellulosic ethanol faces major hurdles including pretreatment, efficient sugar release and fermentation. Several processes were developed to overcome these challenges e.g. simultaneous saccharification and fermentation (SSF). This review highlights the various ethanol production processes with their advantages and shortcomings. Recent technologies such as singlepot biorefineries, combined bioprocessing, and bioenergy systems with carbon capture are promising. However, these technologies have a lower technology readiness level (TRL), implying that additional efforts are necessary before being evaluated for commercial availability. Solving energy needs is not only a technological solution and interlinkage of various factors needs to be assessed beyond technology development.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Etanol/síntese química , Lignina/química , Biomassa , Carboidratos/química , Fermentação
9.
Chemistry ; 26(7): 1588-1596, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31644824

RESUMO

Carbohydrates are involved in many important pathological processes, such as bacterial and viral infections, by means of carbohydrate-protein interactions. Glycoconjugates with multiple carbohydrates are involved in multivalent interactions, thus increasing their binding strengths to proteins. In this work, we report the efficient synthesis of novel muramic and glucuronic acid glycodendrimers as potential Dengue virus antagonists. Aromatic scaffolds functionalized with a terminal ethynyl groups were coupled to muramic and glucuronic acid azides by click chemistry through optimized synthetic strategies to afford the desired glycodendrimers with high yields. Surface Plasmon Resonance studies have demonstrated that the compounds reported bind efficiently to the Dengue virus envelope protein. Molecular modelling studies were carried out to simulate and explain the binding observed. These studies confirm that efficient chemical synthesis of glycodendrimers can be brought about easily offering a versatile strategy to find new active compounds against Dengue virus.


Assuntos
Carboidratos/química , Vírus da Dengue/química , Ácido Glucurônico/síntese química , Ácido Glucurônico/química , Glicoconjugados/síntese química , Glicoconjugados/química , Glicoconjugados/farmacologia , Modelos Moleculares , Ressonância de Plasmônio de Superfície
10.
Gene ; 728: 144287, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31843359

RESUMO

C-type lectins are a superfamily of Ca2+-dependent carbohydrate-binding proteins that play crucial roles in invertebrate immunity. In this study, a novel C-type lectin gene (ScCTL-1) was identified in razor clam Sinonovacula constricta. The ScCTL-1 gene, consisting of four C-type carbohydrate recognition domains (CRDs) with an N-terminal signal peptide and a C-terminal transmembrane region. The gene is widely expressed in almost all tissues, with the highest expression in the hepatopancreas. To explore the functional characteristics of this structurally novel gene, tests of binding specificity, agglutinating activity, and phagocytic promoting activity were included in this study. Bacterial stimulation up-regulated ScCTL-1 expression in hemocytes. The binding activity of rScCTL-1 to bacteria was tested in vitro, and bacterial agglutination was observed under the same conditions. Ca2+ was essential for carbohydrate binding. Additionally, rScCTL-1 promoted the phagocytic activity of hemocytes to varying degrees against different bacteria, unlike the classical opsonin. These results suggest ScCTL-1 is a classical immune-related C-type lectin possessing unique immune-related properties.


Assuntos
Bivalves/genética , Bivalves/imunologia , Hepatopâncreas/metabolismo , Lectinas Tipo C/genética , Fagocitose , Staphylococcus aureus/fisiologia , Vibrio/fisiologia , Aglutinação , Sequência de Aminoácidos , Animais , Bivalves/microbiologia , Carboidratos/química , Filogenia , Domínios Proteicos , Homologia de Sequência , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia
11.
Food Chem ; 309: 125686, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31670130

RESUMO

Reducing sugars can react with 1-phenyl-3-methyl-5-pyrazolone (PMP) to form sugar-PMP derivatives, which can be detected by HPLC-UV or HPLC-DAD due to their high UV absorbance at 248 nm. Six different sugars were synthesized with PMP with aid of response surface methodology (RSM), by which the parameters of the synthesis were designed within temperature ranged between 60 °C and 90 °C, and time from 60 to 180 min, respectively. Consequently, optimal conditions of the glucose (Glu)-, glucosamine (GluN)-, galactose (Gal)-, glucuronic acid (GluA), galacturonic acid (GalA) and glucose-6-phosphate (G6P-PMP) reactions were determined at 71 °C for 129 min, 73 °C for 96 min, 70 °C for 117 min, 75 °C for 151 min, 76 °C for 144 min, and 70 °C for 154 min, respectively. Experiments demonstrated that unique functional groups and delicate differences of carbohydrates' inner pH environment could significantly influence the sugar-PMP reactions. However, sugar stereoisomers did not have remarkable impacts on the reactions.


Assuntos
Carboidratos/análise , Carboidratos/química , Edaravone/química , Cromatografia Líquida de Alta Pressão , Galactose/análise , Galactose/química , Glucosamina/análise , Glucosamina/química , Glucose/análise , Glucose/química , Glucose-6-Fosfato/análise , Glucose-6-Fosfato/química , Ácido Glucurônico/análise , Ácido Glucurônico/química , Ácidos Hexurônicos/análise , Ácidos Hexurônicos/química , Estereoisomerismo
12.
J Enzyme Inhib Med Chem ; 35(1): 383-390, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31865756

RESUMO

A series of new carbohydrate-based sulphonamide derivatives were designed, synthesised by employing the so-call 'sugar-tail' approach. The compounds were evaluated in vitro against a panel of CAs. Compared to their parent compound p-sulfamoylbenzoic acid, these compounds showed nearly 100-fold improvement in their binding affinities against hCA II in vitro. All of compounds showed great water solubility and the pH value of their water solutions of compounds is 7.0. Such properties are advantageous to make them much less irritating to the eye when applied topical glaucomatous drugs, compared to the relatively highly acidic dorzolamide preparations (pH 5.5). Notably, compounds 7d, 7 g, 7 h demonstrated to topically lower intraocular pressure (IOP) in glaucomatous animals better than brinzolamide when applied as a 1% solution directly into the eye. Low cytotoxicity on human cornea epithelial cell was observed in the tested concentrations by the MTT assay.


Assuntos
Anti-Hipertensivos/farmacologia , Carboidratos/farmacologia , Anidrase Carbônica II/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Desenho de Fármacos , Sulfonamidas/farmacologia , Animais , Anti-Hipertensivos/síntese química , Anti-Hipertensivos/química , Carboidratos/química , Anidrase Carbônica II/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Epiteliais , Humanos , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Estrutura Molecular , Ratos , Solubilidade , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
13.
Int J Nanomedicine ; 14: 9089-9112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819421

RESUMO

Purpose: Rifampicin, a first-line anti-tuberculosis drug, was loaded into a carbohydrate-based spray-dried nanocomposite with the aim to design a dry powder inhalation formulation. This strategy can enable efficient distribution of rifampicin within the lungs, localizing its action, enhancing its bioavailability and reducing its systemic exposure consequently side effects. Methods: The respirable nanocomposite was developed utilizing spray drying of rifampicin nanosuspension employing a combination of mannitol, maltodextrin and leucine as microparticles matrix formers. Detailed physicochemical characterization and in-vitro inhalation properties of the nanocomposite particles were investigated. Compatibility studies were carried out using differential scanning calorimetry and Infrared spectroscopy techniques. Moreover, pulmonary in-vitro cytotoxicity on alveolar basal epithelial cells was performed and evaluated. Results: Nanocomposite-based rifampicin-loaded dry inhalable powder containing maltodextrin, mannitol and leucine at a ratio of 2:1:1 was successfully formulated. Rifampicin loading efficiency into the carbohydrate nanocomposite was in the range of 89.3% to 99.2% w/w with a suitable particle size (3.47-6.80 µm) and unimodal size distribution. Inhalation efficiency of the spray-dried nanosuspension was significantly improved after transforming into an inhalable carbohydrate composite. Specifically, mannitol-based powder had higher respirable fraction (49.91%) relative to the corresponding formulation of maltodextrin. Additionally, IC50 value of rifampicin nanocomposite was statistically significantly higher than that of free drug thus providing superior safety profile on lung tissues. Conclusion: The obtained results suggested that spray drying of rifampicin nanosuspension utilizing carbohydrates as matrix formers can enhance drug inhalation performance and reduce cellular toxicity. Thus, representing an effective safer pulmonary delivery of anti-tuberculosis drugs.


Assuntos
Carboidratos/química , Sistemas de Liberação de Medicamentos , Pulmão/efeitos dos fármacos , Nanocompostos/química , Rifampina/farmacologia , Células A549 , Administração por Inalação , Aerossóis , Varredura Diferencial de Calorimetria , Morte Celular , Sobrevivência Celular/efeitos dos fármacos , Inaladores de Pó Seco , Excipientes , Humanos , Manitol/química , Nanocompostos/ultraestrutura , Tamanho da Partícula , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
15.
Int J Nanomedicine ; 14: 7339-7352, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686810

RESUMO

Purpose: To deliver the chemotherapeutics through the nanoparticles, the delivery system should accumulate at the tumor site first and then penetrate through the interstitium into the interior. The specific tumor-targeting pathway mediated via the receptor-ligand binding could achieve the desirable accumulation of nanoparticles, and the nanoparticles with smaller sizes were required for penetration. Methods and materials: We constructed a size-shrinkable nanocluster modified with a tumor-targeting motif IF-7 (IF-7-MNC) based on a pH-sensitive framework which could be disintegrated in an acid environment to release the micelles aggregated inside. The micelles were constructed by amphiphilic block copolymers PEG-PLA to encapsulate paclitaxel (PTX), while the cross-linked framework consisting of TPGS-PEI was used as a net to gather and release micelles. This nanoplatform could specifically bind with the tumor receptor Annexin A1 through the ligand IF-7 and then shrunk into small micelles with a desirable size for penetration. Conclusion: IF-7-MNC of 112.27±6.81 nm could shrink into micelles in PBS (0.01 M, pH 5.0) with sizes of 14.89±0.32 nm. The cellular-uptake results showed that IF-7-MNC could be significantly internalized by A549 cells and HUVEC cells, while the penetration of IF-7-MNC could be more prominent into the 3D-tumor spheroids compared with that of MNC. The biodistribution results displayed that the fluorescence of IF-7-MNC in the tumor site at 24 hrs was 4.5-fold stronger than that of MNC. The results of anti-tumor growth demonstrated that IF-7-MNC was more favorable for the tumor therapy than MNC, where the inhibitory rate of tumor growth was 88.29% in the PTX-loaded IF-7-MNC (IF-7-PMNC) treated group, significantly greater than PMNC treatment group (p<0.05).


Assuntos
Antineoplásicos/farmacologia , Carboidratos/química , Sistemas de Liberação de Medicamentos , Micelas , Nanopartículas/química , Neoplasias/tratamento farmacológico , Tamanho da Partícula , Peptídeos/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Endocitose , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Polietilenoglicóis , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Eletricidade Estática , Distribuição Tecidual
16.
Chemistry ; 25(67): 15419-15423, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31609050

RESUMO

Despite the large variety of modified nucleosides that have been reported, the preparation of constrained 4'-spirocyclic adenosine analogues has received very little attention. We discovered that the [2+2]-cycloaddition of dichloroketene on readily available 4'-exo-methylene furanose sugars efficiently results in the diastereoselective formation of novel 4'-spirocyclobutanones. The reaction mechanism was investigated via density functional theory (DFT) and found to proceed either via a non-synchronous or stepwise reaction sequence, controlled by the stereochemistry at the 3'-position of the sugar substrate. The obtained dichlorocyclobutanones were converted into nucleoside analogues, providing access to a novel class of chiral 4'-spirocyclobutyl adenosine mimetics in eight steps from commercially available sugars. Assessment of the biological activity of designed 4'-spirocyclic adenosine analogues identified potent inhibitors for protein methyltransferase target PRMT5.


Assuntos
Adenosina/química , Nucleosídeos/análogos & derivados , Nucleosídeos/síntese química , Carboidratos/química , Reação de Cicloadição , Teoria da Densidade Funcional , Dicloroetilenos/química , Glicosilação , Metais/química , Estrutura Molecular , Oxirredução , Estereoisomerismo , Termodinâmica
17.
J Basic Microbiol ; 59(12): 1238-1247, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613018

RESUMO

Penicillium griseoroseum lectin was 80-fold purified by successive DEAE Sepharose anion exchange and Sephadex G-100 gel permeation chromatography. P. griseoroseum lectin exhibited haemagglutination activity towards protease-treated rabbit erythrocytes. It showed specificity towards various carbohydrates such as d-mannose, N-acetyl-d-glucosamine, mucins, and so forth. P. griseoroseum lectin was found as a glycoprotein with glycan content of 4.33%. Purified P. griseoroseum lectin is homodimeric having a molecular mass of 57 kDa with subunit molecular mass of 28.6 kDa. Haemagglutination activity of purified P. griseoroseum lectin was completely stable from 25°C to 35°C at a pH range of 6-7.5. Lectin activity was not influenced by divalent metal ions and denaturants. P. griseoroseum lectin manifested mitogenicity towards mice splenocytes and activity reached a peak at 75 µg/ml of lectin concentration. P. griseoroseum lectin in microgram concentrations stimulated proliferation of mice splenocytes. Thus, P. griseoroseum lectin exhibits potential mitogenicity, which can be exploited for further biomedical applications.


Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Mitógenos/química , Mitógenos/isolamento & purificação , Penicillium/química , Animais , Carboidratos/química , Cátions/metabolismo , Proliferação de Células/efeitos dos fármacos , Quelantes , Glicoproteínas/química , Hemaglutinação , Concentração de Íons de Hidrogênio , Lectinas/farmacologia , Masculino , Camundongos , Mitógenos/farmacologia , Peso Molecular , Multimerização Proteica , Estabilidade Proteica , Temperatura
18.
J Agric Food Chem ; 67(45): 12335-12340, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31617360

RESUMO

The Human Microbiome Project has prompted unprecedented advancement in microbiome science. Personalized microbiome modulation with precision (PMMP) is one of the emerging yet challenging fields in microbiome research. Carbohydrate-based prebiotics (CBPs) have been shown to modulate the gut microbiome to various extents according to different structural characteristics, such as degree of polymerization, branching, glycosidic linkage, monosaccharide profile, and chemical modification. Subsequently, a targeted modulation of the microbiome might be achieved by using CBPs with a specific structure. A multidimensional database can be established based on the structure-microbiome and structure-microbial-marker relationships. Such relationships could facilitate the development of synbiotics and PMMP.


Assuntos
Carboidratos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Prebióticos/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Carboidratos/química , Humanos , Intestinos/microbiologia
19.
Molecules ; 24(20)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618818

RESUMO

The predictive power of the two major water bands centered at 6900 cm - 1 and 5200 cm - 1 in the near-infrared (NIR) region was compared to carbohydrate-related spectral areas located in the first overtone (around 6000 cm - 1 ) and combination (around 4500 cm - 1 ) region using glucose in aqueous solutions as a model substance. For the purpose of optimal coverage of stronger as well as weaker absorbing NIR regions, cells with three different declared optical pathlengths were employed. The sample set consisted of multiple separately prepared batches in the range of 50-200 mmol/L. Moreover, the samples were divided into a calibration set for the construction of the partial least squares regression (PLS-R) models and a test set for the validation process with independent samples. The first overtone and combination region showed relative prediction errors between 0.4-1.6% with only one PLS-R factor required. On the other hand, the errors for the water bands were found between 1.6-8.3% and up to three PLS-R factors required. The best PLS-R models resulted from the cell with 1 mm optical pathlength. In general, the results suggested that the carbohydrate-related regions in the first overtone and combination region should be preferred over the regions of the two dominant water bands.


Assuntos
Carboidratos/química , Glucose/química , Espectroscopia de Luz Próxima ao Infravermelho , Água/química , Soluções
20.
Orig Life Evol Biosph ; 49(3): 187-196, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31642022

RESUMO

This work addresses the supramolecular self-organization in the xerogels of formose reaction products. The UV-induced formose reaction was held in over-saturated formaldehyde solutions at 70∘C without a catalyst. The solutions of the obtained carbohydrates were dried on a glass slide, and the obtained xerogels demonstrated a prominent optical activity, while the initial solutions were optically inactive. The xerogels contained highly elongated crystalline elements of a helical structure as well as the isometric ones. Thus xerogel formation was accompanied by a spontaneous resolution of enantiomers and separation of different-shaped supramolecular structures. The thick helices were twisted of thinner ones, while the latter were twisted of elementary structures having a diameter much smaller than 400 nm. Similar structural hierarchy is typical of biological macromolecules (DNA, proteins, and cellulose). Summarizing the obtained results, we proposed a hypothetical mechanism explaining the amplification of the initial enantiomeric excess, as well as chiral and chemical purification of the substances which were essential for the evolution of Life to start.


Assuntos
Carboidratos/química , Formaldeído/química , Géis , Origem da Vida , Estereoisomerismo
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