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1.
J Agric Food Chem ; 68(8): 2588-2596, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32031793

RESUMO

Monosaccharides play important roles in plant growth and development, and their biofunctions are closely related to their endogenous contents. Therefore, the determination of monosaccharides is beneficial for the further study of monosaccharide biofunction. In this work, we developed a liquid chromatography-mass spectrometry analytical method assisted by a post-column derivatization technique (LC-PCD-MS) for the fast and automatic determination of 16 monosaccharides in samples. Post-column chemical derivatization of monosaccharides was performed by a reaction of monosaccharides with 4-benzylaminobenzeneboronic acid (4-PAMBA) through boronate ester formation in a three-way connector. 4-PAMBA worked as a derivatization reagent to improve the selectivity and sensitivity of monosaccharide detection by MS. The developed LC-PCD-MS method integrates LC separation, chemical derivatization, and MS detection in one run, thus greatly reducing the analysis time for each sample. The limits of detection and limits of quantification for 16 monosaccharides were in the range of 0.002-0.1 and 0.007-0.5 ng/mL, respectively. Good linearity was obtained from the linear regression, with a determination coefficient (R2) ranging from 0.9928 to 1.0000. The relative recoveries were in the range of 80.7-117.8%, with the intra- and interday relative standard deviations less than 19.7 and 16.5%, respectively, indicating good accuracy and acceptable reproducibility of the method. Finally, the method was successfully applied to investigate the spatial and temporal distribution of 16 monosaccharides in the developing flower and germinating seed of Arabidopsis thaliana.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Monossacarídeos/análise , Espectrometria de Massas em Tandem/métodos , Arabidopsis/química , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Cromatografia Líquida de Alta Pressão/instrumentação , Flores/química , Flores/crescimento & desenvolvimento , Flores/metabolismo , Limite de Detecção , Monossacarídeos/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Espectrometria de Massas em Tandem/instrumentação
2.
Molecules ; 24(19)2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569331

RESUMO

As an irreversible and complex degenerative physiological process, the treatment for aging seems strategically necessary, and polysaccharides play important roles against aging owing to their abundant bioactivities. In this paper, the antioxidant and anti-aging activities of Flammulina velutipes polysaccharides (FPS) and its sulfated FPS (SFPS) on d-galactose-induced aging mice were investigated. The in vitro antioxidant activities demonstrated that SFPS had strong reducing power and superior scavenging effects on 2, 2-diphenylpicrylhydrazyl (DPPH), hydroxyl radicals and the chelating activities of Fe2+. The in vivo animal experiments manifested that the SFPS showed superior antioxidant and protective abilities against the d-galactose-induced aging by increasing the antioxidant enzyme activities, decreasing lipid peroxidation, improving the inflammatory response and ameliorating the anile condition of mice. Furthermore, the structural analysis of SFPS was investigated through FT-IR, NMR, and HPLC analysis, and the results indicated that SFPS was a homogeneous heteropolysaccharide with a weight-average molecular weight of 2.81 × 103 Da. Furthermore, SFPS has also changed in characteristic functional groups and monosaccharide composition compared to FPS. These results suggested that sulfated modification could enhance the anti-oxidation, anti-aging and protective activities of F. velutipes polysaccharides, which may provide references for the development of functional foods and natural medicines.


Assuntos
Antioxidantes/farmacologia , Flammulina/química , Polissacarídeos Fúngicos/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/química , Polissacarídeos Fúngicos/química , Monossacarídeos/análise , Substâncias Protetoras/química , Análise Espectral
3.
Se Pu ; 37(11): 1162-1172, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642268

RESUMO

A method for the separation, identification, and determination of fructose and various aldehyde monosaccharides was established by precolumn labeling with 1-phenyl-3-methyl-5-pyrazolone (PMP) and high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). The separation was performed on a Kromasil-C18 column (100 mm×4.6 mm, 3.5 µm) with gradient elution. The detection was performed by electrospray ionization mass spectrometry in selected ion monitoring (SIM) mode. In this study, the derivatization mechanism of PMP-labeled fructose was proposed under mild NH3·H2O conditions. The suggested method showed good linearity in the corresponding mass concentration ranges, with the correlation coefficients (r2) > 0.9947. The limits of detection (LODs) and limits of quantification (LOQs) were in the ranges 0.003 to 0.05 mg/L and 0.01 to 0.15 mg/L, respectively. The recoveries in spiked Lycium barbarum L. samples were 65.1% to 116.2%, with relative standard deviations (RSDs) of less than 10.2%. By virtue of its simplicity, high sensitivity, and good repeatability, the method could be successfully applied to the analysis of the monosaccharide composition in polysaccharides of Lycium barbarum L. from four planting areas. Results showed that the isolated polysaccharides comprise mannose, fructose, rhamnose, galactose, glucose, xylose, arabinose, and ribose. The concentration distribution of various monosaccharides differed notably depending on the planted environmention. The proposed method is expected to be of great significance in standardizing the quality control of polysaccharides.


Assuntos
Lycium/química , Monossacarídeos/análise , Polissacarídeos/análise , Cromatografia Líquida de Alta Pressão , Compostos Fitoquímicos/análise , Espectrometria de Massas por Ionização por Electrospray
4.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3221-3225, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602875

RESUMO

The non-starch polysaccharides,mainly composed of glucomannans,are the major bioactive compounds in Dendrobium catenatum. In order to evaluate the quality of the medicinal materials and guide the production and processing,a quantification method of non-starch polysaccharides was established by stems of D. catenatum C15 strain collected from the pear epiphytic cultivation. The non-starch polysaccharides were obtained by " water extraction,α-amylase pretreatment,and alcohol precipitation once" method. The contents of starches,non-starch polysaccharides and monosaccharides were analyzed. In addition,the system suitability was tested. Compared with method of the Chinese Pharmacopoeia( 2015 edition),the contents of total polysaccharides,glucose,and mannose were decreased by 20. 9%,58. 8% and 1. 6% respectively. The method effectively digested starch and retained non-starch polysaccharides,and the analysis result was accurate and repeatable. Therefore,it is suitable for the content measurement of non-starch polysaccharides of D. catenatum. Furthermore,it could be an alternative method for quality control of D. catenatum and a reference in the determination of non-starch polysaccharides in other starch-containing medicinal materials.


Assuntos
Dendrobium/química , Polissacarídeos/análise , Monossacarídeos/análise , Compostos Fitoquímicos/análise , Amido/análise
5.
Carbohydr Res ; 485: 107813, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541938

RESUMO

A novel polysaccharide in Malus halliana Koehne, named MHP-W, was isolated and purified by DEAE-52 cellulose and Sephadex G-100 columns. Structural features were identified by high performance size-exclusion chromatography (HPSEC), fourier transform infrared (FT-IR) spectrometer, gas chromatography (GC) and (1D & 2D) NMR Spectroscopy. Structural characterization showed that the molecular weight of MHP-W was 353 kDa composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 2.59: 0.15: 0.23: 0.25: 9.70. The existence of ß-glycosidic bond between the sugar units was confirmed by FT-IR and NMR spectroscopy. The effects of MHP-W on active part thrombin time (APTT), protothrombin time (PT), thrombin time (TT), and fibrinogen (FIB) were screened by a cell-based coagulation activity model. MHP-W could significantly shorten TT (p < 0.001) and increase FIB (p < 0.05) as compared with the control group. The results showed that MHP-W promoted bloodclotting through endogenous and exogenous coagulation pathways as well as increasing fibrinogen content, which indicated that MHP-W had procoagulant activities in vitro.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Malus/química , Polissacarídeos/farmacologia , Animais , Sequência de Carboidratos , Masculino , Peso Molecular , Monossacarídeos/análise , Polissacarídeos/química , Coelhos
6.
Artigo em Inglês | MEDLINE | ID: mdl-31476578

RESUMO

A baseline dip caused by the reduction of dissolved oxygen in samples has been a source of trouble in the analysis of major monosaccharides (galactose, glucose, mannose, and fructose) in the high-performance anion-exchange chromatography with pulsed amperometric detection system. This study attempted three different methods to remove the baseline dip from the resulting chromatograms, and among the approaches, sodium sulfite was found to act as the best oxygen scavenger. Clean chromatograms were obtained by adding at least 3 mg/mL sodium sulfite to samples, which removed the baseline dip and improved the accuracy of sugar analysis. Although sodium sulfite does not influence analytical sensitivity, it can cause a reduction of sugar retention; however, retention time can be recovered by washing with 200 mM sodium hydroxide solution. Results demonstrated that sodium sulfite is an effective means either to remove the baseline dip for low concentration analysis under 1 mg/L, or to separate the target sugar from the baseline dip by retention time rearrangement.


Assuntos
Cromatografia por Troca Iônica/métodos , Monossacarídeos/análise , Oxigênio/química , Sulfitos/química , Modelos Lineares , Monossacarídeos/química , Reprodutibilidade dos Testes
7.
Carbohydr Polym ; 224: 115195, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472848

RESUMO

Brown seaweeds are well-known source of bioactive compounds, which are producing a variety of secondary metabolites with promising bioactive properties. Traditionally, seaweeds used as ingredients in medicine for many centuries in Asian countries. However, the protective mechanisms of many metabolites found in seaweeds are remains to be determined. Thus, applications of seaweeds are limited because of poor understanding of their structural features and mechanisms responsible for their bioactive properties. In the present study, anti-inflammatory properties of fucoidan isolated from the brown seaweed Padina commersonii (PCF) was evaluated against LPS-activated RAW 264.7 macrophages. PCF was characterized using NMR, FT-IR, and HPAE-PAD spectrum (for mono sugar composition). It was observed that PCF is rich in fucose and sulfate as well as a similar structure to the commercial fucoidan. Western blots and RT-qPCR analysis were used to determine the protective effects of PCF after LPS challenge using RAW 264.7 macrophages. According to the results, PCF significantly down-regulated LPS-activated mRNA and protein expression levels of TLR2, TLR4, and MyD88 which are known inducers/activators of NF-κB transcriptional factors. The results, obtained from this study demonstrated PCF has a potential to inhibit LPS-induced inflammatory responses via blocking TLR/MyD88/ NF-κB signal transduction.


Assuntos
Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , NF-kappa B/metabolismo , Polissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptores Toll-Like/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/genética , Citosol/efeitos dos fármacos , Citosol/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Camundongos , Monossacarídeos/análise , Fator 88 de Diferenciação Mieloide/metabolismo , Óxido Nítrico/metabolismo , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/uso terapêutico , Células RAW 264.7 , RNA Mensageiro/genética
8.
Carbohydr Polym ; 224: 115140, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472853

RESUMO

A new source of pectin with a cytotoxic effect on glioblastoma cells is presented. A homogeneous GWP-FP-S fraction (Mw of 29,170 g mol-1) was obtained by fractionating the crude pectin extract (GW) from Campomanesia xanthocarpa pulp. According to the monosaccharide composition, the GWP-FP-S was composed of galacturonic acid (58.8%), arabinose (28.5%), galactose (11.3%) and rhamnose (1.1%), comprising 57.7% of homogalacturonans (HG) and 42.0% of type I rhamnogalacturonans (RG-I). These structures were characterized by chromatographic and spectroscopic methods; GW and GWP-FP-S fractions were evaluated by MTT and crystal violet assays for their cytotoxic effects. Both fractions induced cytotoxicity (15.55-37.65%) with concomitant increase in the cellular ROS levels in human glioblastoma cells at 25-400 µg mL-1, after 48 h of treatment, whereas no cytotoxicity was observed for normal NIH 3T3 cells. This is the first report of in vitro bioactivity and the first investigation of the antitumor potential of gabiroba pectins.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Glioblastoma/patologia , Pectinas/química , Pectinas/farmacologia , Pimenta/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Monossacarídeos/análise , Pectinas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
9.
Carbohydr Polym ; 224: 115133, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472863

RESUMO

An unprecedented approach towards oligosaccharides containing N-acetylglucosamine-N-acetylmuramic (NAG-NAM) units was developed. These novel bacterial cell wall surrogates were obtained from chitosan via a top down approach involving both chemical and enzymatic reactions. The chemical modification of chitosan using a molecular clamp based strategy, allowed obtaining N-acetylglucosamine-N-acetylmuramic (NAG-NAM) containing oligomers. Intercalation of NAM residues was confirmed through the analysis of oligosaccharide fragments from enzymatic digestion and it was found that this route affords NAG-NAM containing oligosaccharides in 33% yield. These oligosaccharides mimic the carbohydrate basic skeleton of most bacterial cell surfaces. The oligosaccharides prepared are biologically relevant and will serve as a platform for further molecular recognition studies with different receptors and enzymes of both bacterial cell wall and innate immune system. This strategy combining both chemical modification and enzymatic digestion provides a novel and simple route for an easy access to bacterial cell wall fragments - biologically important targets.


Assuntos
Acetilglucosamina/química , Quitosana/química , Ácidos Murâmicos/química , Oligossacarídeos/química , Endopeptidases/metabolismo , Monossacarídeos/análise , Muramidase/metabolismo , Oligossacarídeos/metabolismo
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1126-1127: 121761, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31450088

RESUMO

A variety of scientific and technical fields rely on the analysis of monosaccharides (sugars). However, the multiple isomer forms of individual monosaccharides have long hampered their analyses in complex samples: significant chromatographic co-elution often leads to the loss of information on individual compounds. In addition, the chromatographic enantiomer resolution of monosaccharides has of course received less attention than molecular resolution. This would be expected in the case of rare monosaccharides, but enantiomer resolution of erythrose and threose have also received relatively little attention in the literature. Methods that are capable of the simultaneous molecular and enantiomer resolution/identification of suites of monosaccharides in single complicated mixtures are desirable. Here we report the results of attempts to resolve mixtures of the enantiomers of all three­carbon (3C) to six­carbon (6C) aldehyde (aldose) monosaccharides as acetal-trifluoroacetyl (acetal-TFA) derivatives by gas chromatography-mass spectrometry (GC-MS); glyceraldehyde (3C) is included as its TFA-only derivative. After a relatively simple derivatization procedure, the analyzed acetals are in the ethyl-, 2-propyl- and 2-butyl-TFA forms. Using chiral (cyclodextrin) and non-chiral (DB-17) GC columns we show that these enantiomer pairs can be baseline resolved - depending on the derivative/GC column combination - and that any single acetal/TFA combination can resolve the majority of enantiomers in a single run. Importantly, ribose and lyxose form only one significant (in abundance) stereoisomer with all derivative combinations while other monosaccharides form a maximum of only two significant stereoisomers: this greatly reduces obfuscation due to crowding on a given chromatogram. We conclude that GC-MS of acetal-TFA derivatives is the best (overall) analytical technique, to date, for the analysis of aldose-monosaccharide enantiomer ratios and reduces chromatogram clutter by favorably restricting the proliferation of monosaccharide isomers.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Monossacarídeos , Acetais/química , Modelos Moleculares , Monossacarídeos/análise , Monossacarídeos/química , Monossacarídeos/isolamento & purificação , Estereoisomerismo
11.
Carbohydr Polym ; 223: 115043, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426995

RESUMO

Microwave-assisted hydrothermal extraction of non-structural carbohydrates and hemicelluloses from tobacco biomass was investigated. Non-structural carbohydrates extraction was optimized by an Optimal design. The maximum yields for the leaf and stem were 118.57 mg/g and 120.33 mg/g biomass, respectively. The extracted stem residue was further treated for hemicelluloses extraction. A temperature of 200 °C without holding was proved to be the most efficient condition to produce a hemicelluloses yield of 105.15 mg/g. GPC results showed that the Mw values of precipitated hemicelluloses decreased from 143.5 kDa to 13.25 kDa with increasing temperature and holding time, while the un-precipitated fraction were ranging from 11.83 to 4.88 kDa. Monosaccharide analysis revealed that hemicelluloses extracted at lower temperature are heterogeneous compositional type, including xylan, glucuronoxylan and xylanglucan, while the ratio of xylose increased significantly (up to 72.64%) with increasing temperature. The developed microwave-assisted hydrothermal extraction process opens new avenues for a sustainable tobacco-based biorefinery.


Assuntos
Biomassa , Monossacarídeos/isolamento & purificação , Polissacarídeos/isolamento & purificação , Tabaco/química , Calefação , Temperatura Alta , Micro-Ondas , Peso Molecular , Monossacarídeos/análise , Monossacarídeos/química , Folhas de Planta/química , Caules de Planta/química , Polissacarídeos/análise , Polissacarídeos/química , Extração em Fase Sólida/métodos
12.
Int J Biol Macromol ; 137: 1130-1140, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31295484

RESUMO

This work investigated the protective effects of Ganoderma applanatum residue polysaccharides (GRP) on the CCl4-induced hepatotoxicity. The results indicated that GRP showed significantly effects on preventing the increase of AST, ALT and ALP levels in serum, elevating the activities of SOD, GSH-Px and CAT, decreasing the contents of MDA and LPO, and reducing the CYP2E1 and TGF-ß concentrations in CCl4-induced mice, respectively. Meanwhile, the levels of TNF-α and IL-6 were significantly decreased, while the value of IL-10 was increased by GRP treatment. Besides, the western blot assay showed the IκBα expressions were significantly increased and the p-p65 was decreased by the treatment with GRP. The characterizations indicated that the GRP was heteropolysaccharide with lower molecular weights and α-furanoside residues. These results demonstrated that GRP might be a potential material for drug and functional food development against chemical hepatic injury.


Assuntos
Antioxidantes/farmacologia , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Polissacarídeos Fúngicos/farmacologia , Ganoderma/química , Animais , Antioxidantes/química , Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/complicações , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Cirrose Hepática/complicações , Masculino , Metilação , Camundongos , Monossacarídeos/análise , Estresse Oxidativo/efeitos dos fármacos
13.
Int J Biol Macromol ; 137: 1102-1111, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31276724

RESUMO

Polysaccharopeptide (PSP) from the medicinal mushroom Coriolus versicolor has been widely used in Asia as an adjunctive immunotherapy for treating cancers and liver diseases. However, the composition and structure of bioactive components in PSP remain elusive. Herein, we purified a hepatoprotective polysaccharide (PSP-1b1) with a molecular weight of 21.7 kDa from C. versicolor mycelia in submerged culture. PSP-1b1 consists of fucose, galactose, xylose, mannose, glucuronic acid and glucose at a relative molar ratio of 0.16:0.60:0.02:0.55:0.04:1.00. Structural features were investigated by methylation and gas chromatography-mass spectrometry, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The PSP-1b1 backbone consists of →4)-α-Galp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)-α-Galp-(1 → 2)-α-Manp-(1 → 4)→, with branches of α-1,6-Manp, ß-1,6-Glcp, ß-1,3,6-Glcp, α-1,3-Manp, α-1,6-Galp, α-1,3-Fucp, T-α-Glcp and T-α-Galp on the O-6 position of α-Manp of the main chain, and secondary branches linked to the O-6 position of ß-Glcp of the major branch. Treatment with PSK-1b1 (80 and 160 mg/kg/day) resulted in hepatoprotective effects against alcohol-induced liver injury in mice by reducing oxidative stress and modulating immunity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Etanol/efeitos adversos , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Micélio/química , Trametes/química , Animais , Biomarcadores/sangue , Sequência de Carboidratos , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Citoproteção/efeitos dos fármacos , Polissacarídeos Fúngicos/uso terapêutico , Imunomodulação/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Monossacarídeos/análise , Estresse Oxidativo/efeitos dos fármacos
14.
Int J Biol Macromol ; 137: 139-150, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260772

RESUMO

In the present study, six different polysaccharides (RFPs, MAPs, UWPs, AEPs, HWPs and CEPs) were extracted from Chlorella vulgaris using repeated freeze-thawing, microwave-assisted-, ultrasonic wave-, alkali-, hot water-, and cellulase-based methods; and antioxidant property assays were performed both in vitro and in vivo. Radical-scavenging capacity (using DPPH, superoxide and hydroxyl radicals) and metal chelating ability were assessed in vitro; Caenorhabditis elegans was used to assess antioxidant effects in vivo. Based on the in vitro screening tests, UWPs exhibited high antioxidant capacity. The UWP yield was 17.1% ±â€¯2.2%; the DPPH-, superoxide-, and hydroxyl radical-scavenging rates were 65.1% ±â€¯2.4%, 61.2% ±â€¯2.7%, and 56.2% ±â€¯2.2%, respectively, and the metal chelating ability was 63.6% ±â€¯2.5% at a concentration of 0.4 mg/mL. UWPs also exhibited high antioxidant activity in vivo. UWPs significantly increased the lifespan of C. elegans under oxidative stress induced by hydrogen peroxide compared with the control group, enhanced stress-resistance-related enzymes, including catalase and superoxide dismutase by 7.29% ±â€¯1.8% and 24.41% ±â€¯4.8%, respectively. The results of the present study indicate that the extraction methods of C. vulgaris polysaccharides were a key factor influencing antioxidant activity.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Quelantes/química , Quelantes/farmacologia , Chlorella vulgaris/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Quelantes/isolamento & purificação , Radical Hidroxila/química , Peso Molecular , Monossacarídeos/análise , Estresse Oxidativo/efeitos dos fármacos , Picratos/química , Polissacarídeos/isolamento & purificação , Superóxidos/química , Ondas Ultrassônicas , Água/química
15.
Food Chem ; 298: 124987, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260962

RESUMO

In this study, subcritical water extraction (SWE), SWE in aqueous citric acid (pH 5.0) (SWEC), and ultrasound-assisted SWEC (USWEC) were used to extract soluble dietary fiber (SDF) from wheat bran. Results showed that SWE-based methods significantly influenced the physicochemical, functional, and biological properties of the SDF. The fraction SDF-III attained via USWEC had higher SDF yield (46.30%) and carbohydrate content (82.91%), and lower weight-average molecular weight (65.2 kDa) and particle size (1.17 µm), and looser and more porous surface structure, compared with the SDF-I and SDF-II obtained by SWE and SWEC, respectively. USWEC increased the thermal stability and homogeneity of SDF-III but decreased its apparent viscosity and dynamic viscoelasticity. Moreover, the SDF-III exhibited more significant antioxidant and α-amylase inhibitory activities in vitro than SDF-I and SDF-II. Therefore, the USWEC technique had a greater potential for the highly-efficient production of SDF from wheat bran.


Assuntos
Fracionamento Químico/métodos , Fibras na Dieta , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Cítrico/química , Fibras na Dieta/farmacologia , Difusão Dinâmica da Luz , Inibidores Enzimáticos/farmacologia , Concentração de Íons de Hidrogênio , Peso Molecular , Monossacarídeos/análise , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Água/química , alfa-Amilases/antagonistas & inibidores
16.
Food Chem ; 299: 125094, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31301529

RESUMO

The jaggery-making process involves various thermo-chemical treatments of sugarcane juice. As jaggery making is a traditional practice, knowledge about the use of different chemicals in the process is transferred from generation to generation without much scientific understanding. Phosphoric acid is one of the chemicals commonly used in this process. We have investigated its effect through systematic experiments. The addition of acid causes inversion of sucrose, which beyond a certain point is not desirable for good quality jaggery. In the correct proportions, however, phosphoric acid improves the colour and texture of jaggery and helps in the formation of smaller sized crystals. Reducing sugars formed due to inversion hinder crystal growth, resulting in relatively small crystals. In our experiments, the average crystal size reduced from 22.22 µm to 14.34 µm. Acid-treatedjaggery was found to equilibrate at higher moisture. A comparison with normal jaggery is thus provided for its keeping quality.


Assuntos
Indústria de Processamento de Alimentos/métodos , Ácidos Fosfóricos/química , Extratos Vegetais/química , Saccharum/química , Cor , Cristalização , Flavonoides/química , Monossacarídeos/análise , Extratos Vegetais/análise , Polifenóis/química
17.
Int J Biol Macromol ; 137: 568-575, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279885

RESUMO

Two polysaccharides, DGS1 and DGS2, were obtained by solid-state fermentation (SSF) of Fusarium solani DO7, an endophytic fungus isolated from the orchid Dendrobium officinale. Structural characterizations revealed that DGS1 consisted of arabinose, glucose, mannose and galactose with a molar ratio of 2.9:13.4:3.0:1, respectively, and contained (1 → 5)-Araf, (1 → 4)-Glcp, (1 → 6)-Glcp, (1 → 3)-Manp, (1 → 2,6)-Manp and (1 → 6)-Galp glycosidic linkages, while DGS2 was composed of arabinose, glucose, mannose and galactose in a molar ratio of 3.5:8.1:2.1:1, respectively, and contained (1 → 5)-Araf, (1 → 4)-Glcp, (1 → 6)-Glcp, (1 → 3)-Manp and (1 → 6)-Galp glycosidic linkages. Neither polysaccharide was toxic to human embryonic kidney cells or mouse RAW 264.7 macrophage cells. An immunomodulatory activity assay indicated that both polysaccharides could significantly enhance the levels of TNF-α, IL-6 and NO by activating TNF-α, IL-6 and iNOs gene expression, respectively, especially DGS2. Interestingly, DGS2 also possessed relatively high antioxidant activity. These results illustrate that, due to its cost-effectiveness and environmentally friendly features, SSF has significant potential as a commercially competitive source of natural products, including fungal polysaccharides, with immunomodulatory activity.


Assuntos
Fermentação , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Fusarium/química , Fusarium/metabolismo , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Polissacarídeos Fúngicos/biossíntese , Glicosilação , Células HEK293 , Humanos , Fatores Imunológicos/biossíntese , Metilação , Camundongos , Peso Molecular , Monossacarídeos/análise , Fagocitose/efeitos dos fármacos , Células RAW 264.7
18.
Carbohydr Res ; 482: 107728, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31306897

RESUMO

The cell wall of Rathayibacter iranicus VKM Ac-1602T (family Microbacteriaceae, class Actinobacteria) is characterised by the absence of phosphate-containing and by the presence of two rhamnose-containing glycopolymers. The first is a branched rhamnomannan, in which 60% of mannose residues of the main chain are glycosylated by terminal mannose residues: →2)-α-D-Rhap-(1 → 3)-α-[α-D-Manp-(1 → 6)]-D-Manp-(1 → . The second is a branched teichuronic acid, in which all the rhamnose residues of the main chain are glycosylated by glucose residues:→3)-α-[α-D-Glcp-(1 → 2)]-L-Rhap-(1 → 4)-ß-D-GlcpA-(1 → 2)-α-D-Manp-(1 → 3)-α-D-Galp-(1 → 3)-ß-D-Glcp-(1 → . Both glycopolymers have the unique structures and described in the cell walls of Gram-positive bacteria for the first time. The obtained data allow for a more complete characterisation of the cell wall of the microorganism under investigation and can serve as a phenotypic characterisation of this bacterium. The glycopolymer structures were established using chemical and nuclear magnetic resonance (NMR) spectroscopy methods.


Assuntos
Actinobacteria/citologia , Parede Celular/química , Piranos/química , Ramnose/química , Sequência de Carboidratos , Glicosilação , Monossacarídeos/análise , Estereoisomerismo
19.
Int J Biol Macromol ; 136: 632-641, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220491

RESUMO

As a health-beneficial fruit, watermelon is widely consumed by people around the world. However, components responsible for the health benefits are not yet determined. As watermelon contains a large amount of polysaccharides, these carbohydrates might play an important role in the health benefits. In this work, polysaccharide from watermelon rinds (PWR) was extracted by papain digestion, purified and characterized by GC-MS, SEC/MALS/VD/DRI, FTIR and 1D and 2D NMR which revealed the glycosidic linkages, their locations in branches and backbone. The monosaccharide composition revealed that the extracted polysaccharide was composed of galactose (38.26%), arabinose (26.12%), rhamnose (17.86%), mannose (9.94%), xylose (5.10%) and glucose (2.70%) with a percentage of uronic acid of 45%. A combination of CPG and NMR analysis showed that the extracted polysaccharide is arabinogalactan linked to type I rhamnogalacturonan. we notice that the arabinogalactan was formed by →6)-ß-D-Galp-(1→ as backbone with short branching of arabinose linked in α 1 → 3, rhamnose linked in α 1 → 4, mannose linked in ß 1 → 6 and galactose branches linked in ß 1 → 3. Furthermore, PWR exhibited obvious cytotoxicity ability to human laryngeal carcinoma Hep-2 cells in a dose-and time-dependant manner.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Citrullus/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Monossacarídeos/análise , Polissacarídeos/isolamento & purificação
20.
Int J Biol Macromol ; 136: 579-585, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220498

RESUMO

In the present study, two polysaccharides, SVP2-1 and SVP2-2, were isolated from Patinopecten yessoensis viscera and purified by using DEAE-52 cellulose and Sepharose CL-6B. Both SVP2-1 and SVP2-2 could extend activated partial thromboplastin time (APTT) and thrombin time (TT) and inhibit the transformation of fibrinogen into fibrin (FIB) concentration-dependently, indicating they inhibited clotting and thrombin through intrinsic and common pathways. Of note, SVP2-2 had stronger anticoagulant activity than SVP2-1, and its backbone was determined as →6)-α-Manp (1 → 2)-α-Galp(1 → with Xyl or Glc substituted at C4 of Gal. Based on monosaccharide composition analysis, methylation analysis, and NMR analysis. Further comparison of their monosaccharide analysis and NMR spectra indicates SVP2-1 and SVP2-2 possess the same core structure features, so the higher sulfate content and lower molecular weight may be the possible reasons for the stronger anticoagulant capability of SVP2-2. The present study suggests acidic polysaccharides from scallop viscera as promising anticoagulant candidates.


Assuntos
Anticoagulantes/química , Anticoagulantes/farmacologia , Pectinidae , Polissacarídeos/química , Polissacarídeos/farmacologia , Vísceras/química , Animais , Fibrina/metabolismo , Fibrinogênio/metabolismo , Metilação , Peso Molecular , Monossacarídeos/análise , Tempo de Tromboplastina Parcial , Coelhos , Tempo de Trombina
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