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1.
Molecules ; 28(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37894574

RESUMO

Chondroitin sulfate (CS) is a natural macromolecule polysaccharide that is extensively distributed in a wide variety of organisms. CS is of great interest to researchers due to its many in vitro and in vivo functions. CS production derives from a diverse number of sources, including but not limited to extraction from various animals or fish, bio-synthesis, and fermentation, and its purity and homogeneity can vary greatly. The structural diversity of CS with respect to sulfation and saccharide content endows this molecule with distinct complexity, allowing for functional modification. These multiple functions contribute to the application of CS in medicines, biomaterials, and functional foods. In this article, we discuss the preparation of CS from different sources, the structure of various forms of CS, and its binding to other relevant molecules. Moreover, for the creation of this article, the functions and applications of CS were reviewed, with an emphasis on drug discovery, hydrogel formation, delivery systems, and food supplements. We conclude that analyzing some perspectives on structural modifications and preparation methods could potentially influence future applications of CS in medical and biomaterial research.


Assuntos
Materiais Biocompatíveis , Sulfatos de Condroitina , Animais , Sulfatos de Condroitina/química , Polissacarídeos , Fermentação , Suplementos Nutricionais
2.
Int J Biol Macromol ; 219: 44-52, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-35905766

RESUMO

With the gradual global standardization of carbon emission policies, the development of renewable resources to replace traditional fossil resources is assuming increasing importance. Lignin is the most abundant natural source of aromatic compounds and has the potential to replace petroleum-based aromatic hydrocarbons. In this work, the rigid benzene ring structure and excellent photothermal properties of lignin were exploited to produce light-driven lignin-based shape memory polymers (ELEPs) that contain high proportions of lignin and have good mechanical properties. Enzymatically hydrolyzed lignin (EL), epoxy soybean oil (ESO) and polyethylene glycol (PEG 400) were copolymerized and cured to form ELEPs, which have a disordered three-dimensional network. An increase in the proportion of EL from 40 to 60 wt% enhanced the mechanical properties, as reflected by an increase in tensile strength from 11.3 to 30.8 MPa and in the glass transition temperature (Tg) from 93 to 115.7 °C. Under simulated solar irradiation (2000 W m-2), ELEP50, which contains 50 wt% lignin and has a Tg of 105 °C, reached a surface temperature as high as 105 °C and achieved shape memory within 20 s. The shape fixation ratio (Rf) and shape recovery ratio (Rr) were stably >98 % and >97 %, respectively, over eight cycles in a bending-recovery experiment. The unique light-driven shape memory properties of ELEPs provide a method for high value utilization of EL, and the design strategy offers new ideas for producing novel intelligent materials.


Assuntos
Petróleo , Materiais Inteligentes , Benzeno , Carbono , Lignina/química , Polietilenoglicóis , Óleo de Soja
3.
Front Genet ; 12: 683255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276785

RESUMO

Thiamine metabolism dysfunction syndrome 2 (THMD2) is a rare metabolic disorder caused by SLC19A3 mutations, inherited in autosomal recessive pattern. As a treatable disease, early diagnosis and therapy with vitamin supplementation is important to improve the prognosis. So far, the reported cases were mainly from Saudi Arab regions, and presented with relatively simple clinical course because of the hot spot mutation (T422A). Rare Chinese cases were described until now. In this study, we investigated 18 Chinese THMD2 patients with variable phenotypes, and identified 23 novel SLC19A3 mutations, which expanded the genetic and clinical spectrum of the disorder. Meanwhile, we reviewed all 146 reported patients from different countries. Approximately 2/3 of patients presented with classical BTBGD, while 1/3 of patients manifested as much earlier onset and poor prognosis, including infantile Leigh-like syndrome, infantile spasms, neonatal lactic acidosis and infantile BTBGD. Literature review showed that elevated lactate in blood and CSF, as well as abnormal OXPHOS activities of muscle or skin usually correlated with infantile phenotypes, which indicated poor outcome. Brainstem involvement on MRI was more common in deceased cases. Thiamine supplementation is indispensable in the treatment of THMD2, whereas combination of biotin and thiamine is not superior to thiamine alone. But biotin supplementation does work in some patients. Genotypic-phenotypic correlation remains unclear which needs further investigation, and biallelic truncated mutations usually led to more severe phenotype.

4.
Int J Biol Macromol ; 183: 1248-1256, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33965495

RESUMO

Potato starch with high viscosity and digestibility cannot be added into some foods. To address this issue, a novel starch-acting enzyme 4,6-α-glucosyltransferase from Streptococcus thermophilus (StGtfB) was used. StGtfB decreased the iodine affinity and the molecular weight, but increased the degree of branching of starch at a mode quite different from glycogen 1,4-α-glucan branching enzyme (GBE). StGtfB at 5 U/g substrate mainly introduced DP 1-7 into amylose (AMY) or DP 1-12 branches into amylopectin (AMP), and increased the ratio of short- to long-branches from 0.32 to 2.22 or from 0.41 to 2.50. The DP 3 branch chain was the most abundant in both StGtfB-modified AMY and StGtfB-modified AMP. The DP < 6 branch chain contents in StGtfB-modified AMY were 42.68%, much higher than those of GBE-modified AMY. StGtfB significantly decreased viscoelasticity but still kept pseudoplasticity of starch. The modifications also slowed down the glucose generation rate of products at the mammalian mucosal α-glucosidase level. The slowly digestible fraction in potato starch increased from 34.29% to 53.22% using StGtfB of 5 U/g starch. This low viscoelastic and slowly digestible potato starch had great potential with respect to low and stable postprandial blood glucose.


Assuntos
Glucosiltransferases/metabolismo , Solanum tuberosum/química , Amido/química , Streptococcus thermophilus/enzimologia , Amilopectina/metabolismo , Amilose/metabolismo , Proteínas de Bactérias/metabolismo , Elasticidade , Hidrólise , Iodo/química , Peso Molecular , Viscosidade
5.
Food Chem ; 309: 125671, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31670129

RESUMO

A pure glycoprotein (BGP4-I) was obtained from tartary buckwheat seeds by aqueous extraction followed by DEAE-Sepharose Fast Flow ion exchange chromatography and Sephadex G-100 gel filtration chromatography. The average molecular weight of BGP4-I, as determined by high performance gel permeation chromatography, was 123.43 kDa. The structure of BGP4-I was characterized based on Fourier transform infrared spectroscopy, circular dichroism spectroscopy, and nuclear magnetic resonance spectroscopy, etc. Based on the nano-liquid chromatography-coupled electrospray ionization mass spectrometry analysis of the amino acid sequence of BGP4-I, belongs unequivocally to the glycosyl hydrolase family 1 in the Carbohydrate Active Enzymes database by alignment studies. The specific activity of BGP4-I was 18.44 µmol/min/mg on the substrate p-nitrophenyl-ß-d-glucopyranoside. Furthermore, BGP4-I is unique in its specificity for some substrates. These results suggest that the BGP4-I from tartary buckwheat seeds is a novel specific ß-glucosidase setting the foundation for potential applications in the food industry.


Assuntos
Fagopyrum/metabolismo , Glicoproteínas/química , Proteínas de Plantas/química , Sementes/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Glicoproteínas/isolamento & purificação , Glicoproteínas/metabolismo , Peso Molecular , N-Glicosil Hidrolases/química , N-Glicosil Hidrolases/isolamento & purificação , N-Glicosil Hidrolases/metabolismo , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Especificidade por Substrato , Espectrometria de Massas em Tandem
6.
Food Funct ; 10(9): 5461-5472, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31406968

RESUMO

ß-Glucosidase (BG) was immobilized on the surface of bifunctionalized nano-magnetic iron oxide with silica and amine groups (Fe3O4@SiO2-NH2). The aroma and flavonoid aglycone enhancement effect of BG in tea soup was investigated. The immobilized BG-synthesized nanocomposite morphology and structure were characterized by using different analytical techniques, including Fourier transform infrared spectroscopy and scanning electron microscopy. The immobilized BG showed enhanced pH and temperature endurance at an optimum pH of 5.0 and temperature of 65 °C. After seven cycles of reuse, immobilized BG showed 51.8% initial activity. Immobilized-BG treatment in green tea and black tea soup elevated the aroma content by approximately 16% and 48%, respectively. In addition, flavonoid aglycones, such as myricetin, kaempferol, and quercetin, in green tea and black tea soup increased by approximately 65- and 5-fold, respectively. These results suggested that immobilized BG showed excellent potential in the enhancement of aroma and effectively hydrolyzed the flavonoid glycosides to release flavonoid aglycones in tea soup. Hence, this study provides a green and sustainable approach for the tea industry to efficiently enhance tea soup properties.


Assuntos
Fagopyrum/enzimologia , Flavonoides/química , Proteínas de Plantas/química , Chá/química , beta-Glucosidase/química , Biocatálise , Enzimas Imobilizadas/química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Odorantes/análise
7.
Food Chem ; 288: 68-77, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902316

RESUMO

The present work investigated the phenolic profiles, antioxidant activities, and cytoprotective effects of the free, esterified, and insoluble-bound phenolic fractions from oil palm fruits treated under ultra-high pressure (UHP). Results showed that UHP treatment significantly increased the total phenolic and flavonoid contents of all three phenolic fractions (p < 0.05). A total of 11 and 12 phenolic compounds were detected and quantified in non-treated and UHP-treated fruits, with caffeic acid having the highest concentration in insoluble-bound phenolic fractions with 8.68 and 11.27 mg/g of dry extract, respectively. The antioxidant activities, intracellular reactive oxygen species inhibition, and cytoprotective effects of all three phenolic fractions were dramatically enhanced after UHP pretreatment (p < 0.05). Therefore, UHP-treated oil palm fruits with increased bioactivities could be used in functional food or the nutraceutical industry to enhance their applications and economic value.


Assuntos
Antioxidantes/química , Arecaceae/química , Óleo de Palmeira/química , Fenóis/química , Apoptose/efeitos dos fármacos , Arecaceae/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/farmacologia , Frutas/química , Frutas/metabolismo , Células Hep G2 , Humanos , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/química , Pressão , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray
9.
Molecules ; 23(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572648

RESUMO

The present study investigated the phenolic profiles and antioxidant properties of different fractions from Prinsepia utilis Royle fruits using molecular docking analysis to delineate their inhibition toward digestive enzymes. A total of 20 phenolics was identified and quantified. Rutin, quercetin-3-O-glucoside, and isorhamnetin-3-O-rutinoside were the major phenolic compounds in the total phenolic fraction and flavonoid-rich fraction. The anthocyanin-rich fraction mainly contained cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside. All of the fractions exhibited strong radical scavenging activities and good inhibition on cellular reactive oxygen species (ROS) generation in H2O2-induced HepG2 cells, as evaluated by DPPH and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. Moreover, the powerful inhibitory effects of those fractions against pancreatic lipase and α-glucosidase were observed. The major phenolic compounds that were found in the three fractions also showed good digestive enzyme inhibitory activities in a dose-dependent manner. Molecular docking analysis revealed the underlying inhibition mechanisms of those phenolic standards against digestive enzymes, and the theoretical analysis data were consistent with the experimental results.


Assuntos
Frutas/química , Fenóis/análise , Extratos Vegetais/química , Antioxidantes/química , Antioxidantes/farmacologia , Benzotiazóis , Compostos de Bifenilo/metabolismo , Ativação Enzimática/efeitos dos fármacos , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Lipase/metabolismo , Simulação de Acoplamento Molecular , Picratos/metabolismo , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ácidos Sulfônicos , alfa-Glucosidases/metabolismo
10.
Food Chem Toxicol ; 119: 14-23, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29886233

RESUMO

In the present work, acute and subchronic toxicities of the ethanol and hot-water extracts from Rhus chinensis Mill. fruits were performed by oral administration in pathogen-free SD rats. Acute toxicity study was performed at a single dose of 5000 mg/kg for 14 consecutive days. And subchronic toxicity test was conducted by daily oral administration of those two extracts at doses of 312, 625, 1250 and 2500 mg/kg for 30 days. Acute toxicity study showed that the LD50 of the ethanol and hot-water extracts were over 5000 mg /kg. The results of subchronic toxicity showed that no significant adverse effect of those two extracts was observed at 312 and 625 mg/kg. However, the weight gains of rats were significantly inhibited at both 2500 mg/kg groups of the ethanol and hot-water extracts. Moreover, those two extracts exhibited toxicities to heart, liver, spleen and kidney in rats determined by hematological, serum biochemical and/or histological analyses when daily oral administration of 1250 mg/kg and 2500 mg/kg. No significant neurotoxicity was observed in all groups. The results concluded that the low concentration of those two extracts from R. chinensis Mill. fruits can be regarded as safe and used in daily life.


Assuntos
Frutas/química , Extratos Vegetais/toxicidade , Rhus/química , Administração Oral , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Etanol , Feminino , Masculino , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade , Água
11.
Pediatr Int ; 59(11): 1183-1188, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28891253

RESUMO

BACKGROUND: Nocturnal enuresis (NE) is a common pediatric developmental disorder. Desmopressin is frequently used for NE and is an evidence-based therapy. Suoquan capsule is a Chinese medicine commonly used for treating NE in children but is poorly understood by most scholars. METHODS: A total of 369 children with NE were randomized to receive either suoquan, desmopressin plus suoquan, desmopressin, or behavioral intervention for 2 months, and the response rates evaluated. Subsequently, the viable demographic factors that could lead to success were investigated on logistic regression analysis. Moreover, after 3 months of follow up, the relapse rate was investigated. RESULTS: The complete response (CR) rate in the desmopressin plus suoquan group (37.5%) was higher than that in the behavioral intervention group (6.3%, P < 0.007). The desmopressin group had a lower CR rate (22.5%) and a higher non-response rate (25.0%) than the desmopressin plus suoquan group (non-response rate, 21.9%; P > 0.007). The relapse rate in the desmopressin group was significantly higher than that in the desmopressin plus suoquan group (72.2% vs. 30.6%, P < 0.007). On Multivariate analysis, treatment group, NE frequency, and age were independent predictors of CR at 2 months (P < 0.05). CONCLUSIONS: Combined traditional Chinese and Western treatment in children with NE is effective and has a low relapse rate. NE frequency, treatment method, and age are important predictive factors for CR after treatment.


Assuntos
Antidiuréticos/administração & dosagem , Terapia Comportamental/métodos , Desamino Arginina Vasopressina/administração & dosagem , Medicina Tradicional Chinesa/métodos , Enurese Noturna/terapia , Adolescente , Criança , Pré-Escolar , Quimioterapia Combinada , Feminino , Humanos , Masculino , Resultado do Tratamento
12.
Biosens Bioelectron ; 85: 496-502, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27209576

RESUMO

Due to uranium's increasing exploitation in nuclear energy and its toxicity to human health, it is of great significance to detect uranium contamination. In particular, development of a rapid, sensitive and portable method is important for personal health care for those who frequently come into contact with uranium ore mining or who investigate leaks at nuclear power plants. The most stable form of uranium in water is uranyl ion (UO2(2+)). In this work, a UO2(2+) responsive smart hydrogel was designed and synthesized for rapid, portable, sensitive detection of UO2(2+). A UO2(2+) dependent DNAzyme complex composed of substrate strand and enzyme strand was utilized to crosslink DNA-grafted polyacrylamide chains to form a DNA hydrogel. Colorimetric analysis was achieved by encapsulating gold nanoparticles (AuNPs) in the DNAzyme-crosslinked hydrogel to indicate the concentration of UO2(2+). Without UO2(2+), the enzyme strand is not active. The presence of UO2(2+) in the sample activates the enzyme strand and triggers the cleavage of the substrate strand from the enzyme strand, thereby decreasing the density of crosslinkers and destabilizing the hydrogel, which then releases the encapsulated AuNPs. As low as 100nM UO2(2+) was visually detected by the naked eye. The target-responsive hydrogel was also demonstrated to be applicable in natural water spiked with UO2(2+). Furthermore, to avoid the visual errors caused by naked eye observation, a previously developed volumetric bar-chart chip (V-Chip) was used to quantitatively detect UO2(2+) concentrations in water by encapsulating Au-Pt nanoparticles in the hydrogel. The UO2(2+) concentrations were visually quantified from the travelling distance of ink-bar on the V-Chip. The method can be used for portable and quantitative detection of uranium in field applications without skilled operators and sophisticated instruments.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Lagos/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Resinas Acrílicas/química , Sequência de Bases , Colorimetria/métodos , Ouro/química , Dispositivos Lab-On-A-Chip , Limite de Detecção , Nanopartículas Metálicas/química
13.
J Biotechnol ; 184: 47-55, 2014 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-24858678

RESUMO

We previously reported successful cryopreservation of shoot tips of potato 'Zihuabai' by three vitrification-based protocols. In the present study, cryo-injury to shoot tips and genetic stability in regenerants recovered from cryopreserved shoot tips by the three vitrification-based protocols were further investigated. The results showed that sucrose preculture caused no obviously different injuries, while dehydration with plant vitrification solution 2 (PVS2) was the step causing major damage to cells of shoot tips, regardless of the cryogenic procedures. Compared with droplet-vitrification and encapsulation-vitrification, vitrification caused the most severe injury to cells of the shoot tips, thus resulting in much longer time duration for shoot recovery and much lower shoot regrowth rate. Cells in apical dome and the youngest leaf primordia were able to survive and subsequently some of them regrew into shoots following all three vitrification-based cryopreservation procedures. Analyses using inter-simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) markers in shoots regrown from all three vitrification-based protocols did not find any polymorphic bands. The results reported here suggest that vitrification-based cryo-procedures can be considered promising methods for long-term preservation of potato genetic resources.


Assuntos
Criopreservação , Brotos de Planta/crescimento & desenvolvimento , Solanum tuberosum/crescimento & desenvolvimento , Vitrificação , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Instabilidade Genômica , Brotos de Planta/genética , Solanum tuberosum/genética
14.
Planta Med ; 75(3): 230-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19085813

RESUMO

Four novel bakkenolides - bakkenolide-Ia ( 1), bakkenolide-IIa ( 2), bakkenolide-IIIa ( 3) and bakkenolide-IVa ( 4) - were isolated from the extract of the rhizome of Petasites tricholobus. The structures were characterized by using NMR ( (1)H, (13)C, (1)H- (1)H COSY, HMQC, HMBC, and NOESY) and mass spectrometry. The neuroprotective activity of the compounds 1 - 4 was assayed with primary cultured neurons exposed to oxygen-glucose deprivation and oxidative insults. Antioxidant activity of the bakkenolides was evaluated by cell-free bioassays. The IN VITRO assay results showed that all these compounds exhibited significant neuroprotective and antioxidant activities. To our knowledge, this is the first report on the neuroprotective and antioxidant activities of bakkenolides.


Assuntos
4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Petasites/química , Compostos de Espiro/farmacologia , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Glucose/metabolismo , L-Lactato Desidrogenase/metabolismo , Estrutura Molecular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Oxigênio/metabolismo , Ratos , Rizoma , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação
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