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1.
Anal Chem ; 87(17): 8957-63, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26222954

RESUMEN

Low molecular weight heparins (LMWHs) are polydisperse and microheterogenous mixtures of polysaccharides used as anticoagulant drugs. Profiling analysis is important for obtaining deeper insights into the structure of LMWHs. Previous oligosaccharide mapping methods are relatively low resolution and are unable to show an entire picture of the structural complexity of LMWHs. In the current study a profiling method was developed relying on multiple heart-cutting, two-dimensional, ultrahigh performance liquid chromatography with quadruple time-of-flight mass spectrometry. This represents an efficient, automated, and robust approach for profiling LMWHs. Using size-exclusion chromatography and ion-pairing reversed-phase chromatography in a two-dimensional separation, LMW components of different sizes and LMW components of the same size but with different charges and polarities can be resolved, providing a more complete picture of a LMWH. Structural information on each component was then obtained with quadrupole time-of-flight mass spectrometry. More than 80 and 120 oligosaccharides were observed and unambiguously assigned from the LMWHs, nadroparin and enoxaparin, respectively. This method might be useful for quality control of LMWHs and as a powerful tool for heparin-related glycomics.


Asunto(s)
Heparina de Bajo-Peso-Molecular/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Factores de Tiempo
2.
Zhongguo Zhong Yao Za Zhi ; 38(2): 199-203, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23672041

RESUMEN

To study the chemical constituents of Rabdosia japonica var. glaucocalyx and their anti-complementary activity on the basis of preliminary studies. Target isolation guided by anti-complementary activity test, compounds in the chloroform and n-butanol fractions were isolated and purified by silica gel and Sephadex LH-20 column chromatographies, and preparative HPLC. The structures were identified by various spectroscopic data including ESI-MS, 1H-NMR and 13C-NMR data. The compounds were evaluated for anti-complementary activity in vitro. Eleven compounds were isolated from the chloroform and n-butanol soluble fractions and identified as stigmasterol (1), stigmas-9 (11) -en-3-ol (2), glaucocalyxin D (3), kamebakaurin (4), maslinic acid (5), corosolic acid (6), minheryins I (7), diosmetin (8), caffeic acid ethylene ester (9), caffeic acid (10) and vitexin (11). Isoquercetrin, rutin, quercetin, 3-methylquercetin, luteolin, 7-methylluteolin, and apigenin which were isolated from the preliminary studies together with compounds 9 and 10 showed inhibition of the complement system by the classical pathway. Compounds 2, 4, 6-9 and 11 were obtained from this plant for the first time. Caffeic acid (10) showed the strongest activity in vitro with a CH50 value of 0.041 g x L(-1).


Asunto(s)
Antioxidantes/farmacología , Ácidos Cafeicos/farmacología , Ensayo de Actividad Hemolítica de Complemento/métodos , Inactivadores del Complemento/farmacología , Medicamentos Herbarios Chinos/química , Isodon/química , Animales , Cromatografía , Cromatografía Líquida de Alta Presión , Inactivadores del Complemento/química , Cricetinae , Medicamentos Herbarios Chinos/aislamiento & purificación , Eritrocitos/efectos de los fármacos , Ésteres , Etilenos/farmacología , Femenino , Espectroscopía de Resonancia Magnética , Masculino , Componentes Aéreos de las Plantas/química , Reguladores del Crecimiento de las Plantas/farmacología , Ovinos , Espectrometría de Masa por Ionización de Electrospray
3.
J Asian Nat Prod Res ; 14(7): 652-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22582886

RESUMEN

Three new acyclic diterpenoids were isolated from the whole plant of Eupatorium lindleyanum DC. The structures of the compounds were elucidated by means of (1)H and (13)C NMR spectroscopic analyses, including 2D NMR experiments.


Asunto(s)
Diterpenos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Eupatorium/química , Diterpenos/química , Medicamentos Herbarios Chinos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
4.
J Toxicol Environ Health A ; 72(11-12): 752-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19492239

RESUMEN

This study examined the protein expression in lung tissues of rats exposed to radon and cigarette smoke using a proteomic approach. Male Wistar rats were exposed daily to radon at a concentration of 100,000 Bq/m(3) for 16 h, and then exposed to 20% cigarette smoke for 1 h for a period of 75 d, with the radon cumulative dose reaching 200 WLM (working level months). Proteins from rat lung tissue were separated by two-dimensional gel electrophoresis (2-DE), stained with Coomassie blue, and analyzed with ImageMaster two-dimensional (2D) platinum software. Differentially expressed proteins were analyzed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MALDI-time of flight [TOF] MS or MALDI TOF/TOF-MS). Twenty prominent proteins that were correlated with signal transduction, metabolism, heat shock and stress, and cytoskeleton construction were identified. Some of the differential expression proteins were verified by Western blot analysis and immunohistochemical staining, and the results were consistent with 2-DE analysis. The identified proteins and peptides might be potential diagnostic markers of lung impairment induced by radon and cigarette smoke exposure.


Asunto(s)
Pulmón/efectos de los fármacos , Pulmón/efectos de la radiación , Radón/efectos adversos , Contaminación por Humo de Tabaco/efectos adversos , Animales , Biomarcadores/análisis , Citoesqueleto/efectos de los fármacos , Citoesqueleto/efectos de la radiación , Regulación hacia Abajo , Electroforesis en Gel Bidimensional , Regulación de la Expresión Génica , Pulmón/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Proteómica , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Transducción de Señal/efectos de la radiación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Regulación hacia Arriba
5.
Chin J Nat Med ; 17(10): 792-800, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31703760

RESUMEN

Polysaccharide from traditional Chinese herb, Saposhnikovia divaricata (Turcz.) Schischk. (SD) was extracted, fractionated and characterized in this work. Four fractions were prepared. Their molecular weight, monosaccharide compositions, linkage modes and structural properties were characterized with SEC-MALS-RI, HPAEC-PAD, GC-MS and NMR. SDP1 was assigned as a 1, 4-α-glucan with small amount of O-6 linked branches. SDP2 contained a big amount of the 1, 4-α-glucan and a small amount of arabinogalactan, while SDP3 possessed relatively lower amount of the 1, 4-α-glucan and a big amount of the arabinogalactan. SDP4 was defined as a pectic arabinogalactan. Four fractions showed antioxidant activities in both molecular and cellular levels and their activity was ranked as SDP4 ≈ SDP3>SDP2>SDP1. The 1, 4-α-glucan in SDP1 had the weakest, while SDP3 and SDP4 showed similar and the highest antioxidant activity. The arabinogalactan was the major component of both SDP3 and SDP4, which significantly contributed to the antioxidant activity of SDP.


Asunto(s)
Antioxidantes/química , Antioxidantes/aislamiento & purificación , Apiaceae/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Animales , Antioxidantes/farmacología , Supervivencia Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Ratones , Raíces de Plantas/química , Polisacáridos/farmacología , Células RAW 264.7
6.
Toxicol Lett ; 178(3): 191-6, 2008 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-18467043

RESUMEN

Cigarette smoke has been widely investigated in terms of epidemiological and pathological studies in relation to human lung diseases. In this study, we conducted a proteomic analysis to characterize the differential protein expression in lung tissue of rats exposed to cigarette smoke. Wistar rats were exposed to cigarette smoke twice a day, 30 min each for 1, 2 and 4 months, respectively. The total protein of lung tissue was extracted for two-dimensional electrophoresis (2-DE) and analyzed with ImageMaster 2D Platinum software. A total of 28 differentially expressed proteins between the control and the smoke-exposed groups were screened and of which 18 were identified by matrix assistant laser desorption ion-top of flight-mass spectrometry (MALDI-TOF-MS) or MALDI- TOF-TOF analysis, revealing 10 up-regulated and 8 down-regulated proteins. The up-regulated expression of two proteins, receptor for advanced glycation endpoints (RAGE) and thioredoxin (Trx), were validated by immunoblotting and found to be consistent with the proteomic analysis. The results presented in this study demonstrate the identification of proteomic pattern as an early indicator of lung damages induced by cigarette smoke. The differentially expressed proteins may be applied as exposure biomarkers in future experimental as well as epidemiologic investigations upon confirmation by a greater sample size and more validate study design for the proteomic research.


Asunto(s)
Pulmón/efectos de los fármacos , Pulmón/metabolismo , Proteoma/metabolismo , Humo/efectos adversos , Animales , Biomarcadores/metabolismo , Electroforesis en Gel Bidimensional , Regulación de la Expresión Génica , Exposición por Inhalación , Pulmón/patología , Masculino , Proteómica , Ratas , Ratas Wistar , Receptor para Productos Finales de Glicación Avanzada , Receptores Inmunológicos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem , Tiorredoxinas/metabolismo , Nicotiana
7.
J Toxicol Environ Health A ; 71(6): 361-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18246495

RESUMEN

The aim of this study was to investigate the differential expression of proteins in lung of rats following long-term exposure to radon. The total proteins of lung tissue from Wistar rats exposed to radon for cumulative doses up to 100, 200, or 400 WLM (working level months) were isolated by two-dimensional electrophoresis (2-DE) and analyzed with ImageMaster 2D Platinum software. Comparison of the 2-DE images between the control and radon-exposed groups resulted in 14 upregulated and 9 downregulated protein spots, of which 15 were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) or matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF-MS). The simultaneous up-expressions of RAGE and S100A6 indicated that both proteins might be applied as biomarkers for lung injury induced by long-term radon exposure.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Proteoma/metabolismo , Radón/farmacología , Animales , Relación Dosis-Respuesta a Droga , Electroforesis en Gel Bidimensional , Pulmón/patología , Masculino , Proteómica , Ratas , Ratas Wistar , Receptor para Productos Finales de Glicación Avanzada , Receptores Inmunológicos/metabolismo , Proteínas S100/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
8.
J Pharm Anal ; 7(2): 87-94, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29404022

RESUMEN

The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities. This work describes a strategy that combines an efficient release, labeling and liquid chromatography-mass spectral analysis with the use of a comprehensive database to analyze N-glycans. The analytical method described relies on a recently commercialized kit in which quick deglycosylation is followed by rapid labeling and cleanup of labeled glycans. This greatly improves the separation, mass spectrometry (MS) analysis and fluorescence detection of N-glycans. A hypothetical database, constructed using GlycResoft, provides all compositional possibilities of N-glycans based on the common sugar residues found in N-glycans. In the initial version this database contains >8,700 N-glycans, and is compatible with MS instrument software and expandable. N-glycans from four different well-studied glycoproteins were analyzed by this strategy. The results provided much more accurate and comprehensive data than had been previously reported. This strategy was then used to analyze the N-glycans present on the membrane glycoproteins of gastric carcinoma cells with different degrees of differentiation. Accurate and comprehensive N-glycan data from those cells was obtained efficiently and their differences compared corresponding to their differentiation states. Thus, the novel strategy developed greatly improves accuracy, efficiency and comprehensiveness of N-glycan analysis.

9.
Carbohydr Polym ; 158: 85-92, 2017 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-28024546

RESUMEN

Hyaluronic acid (HA), a glycosaminoglycan, is a linear polysaccharide with negative charge, composed of a repeating disaccharide unit [→4)-ß-d-glucopyranosyluronic acid (1→3)-ß-d- N-acetyl-d-glucoaminopyranose (1→]n ([→4) GlcA (1→3) GlcNAc 1→]n). It is widely used in different applications based on its physicochemical properties associated with its molecular weight. Enzymatic digestion by polysaccharides lyases is one of the most important ways to decrease the molecular weight of HA. Thus, it is important to understand the action patterns of lyases acting on HA. In this study, the action patterns of two common lyases, Flavobacterial chondroitinase AC I and Streptomyces hyaluronidase, were investigated by analyzing HA oligosaccharide digestion products. HA oligosaccharides having an odd-number of saccharide residues were observed in the products of both lyases, but their distributions were quite different. Chondroitinase AC acted more efficiently at the ß 1-4 glycosidic bond linking GlcNAc and GlcA. Oligosaccharides, having an even number of saccharide residues, and with an unsaturated uronic acid (4-deoxy-α-l-threo-hex-4-enepyranosyluronic acid, △UA) residue at their non-reducing end represent the major product. A minor amount of oligosaccharides having an odd number of saccharide residues resulted from the irregular terminal residues of HA substrate chains. Hyaluronidase showed a more complicated product mixture. Its minimum recognition and digestion domain is HA heptasaccharide and it could cleave both ß 1-4 and ß 1-3 glycosidic linkages. The HA oligosaccharides, generated with a 2-acetamido-2,3-di-deoxy-ß-d-erythro-hex-2-enopyranose (△HexNAc) at the non-reducing end, are believed to be unstable and undergo breakdown immediately after their generation, and the oligosaccharides with △UA residue at the non-reducing end are formed. Thus, oligosaccharides having both an even and odd-number saccharide residues with a △UA residue at their non-reducing ends, represent the major products of hyaluronidase acting on HA.


Asunto(s)
Condroitinasas y Condroitín Liasas/metabolismo , Ácido Hialurónico/metabolismo , Hialuronoglucosaminidasa/metabolismo , Bacterias/enzimología
10.
Carbohydr Polym ; 155: 483-490, 2017 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-27702538

RESUMEN

Microcrystalline cellulose, a major component of cell wall of plants, is one of the most abundant natural materials, but the poor solubility of cellulose limits its applications. Cellulose is a linear glucan with exclusive ß 1→4 linkage. Oxidation carried out with TEMPO-NaBr-NaClO system can selectively oxidize the C6 of glucose residues in cellulose. This modification improves polysaccharide solubility and other physicochemical properties. In this work, the impact of degree of oxidation on solubility, degree of crystallization, thermostability, molecular weight and the structures of the resulting oligosaccharide products of selectively oxidized cellulose were investigated using x-ray diffraction, thermogravimetric analysis, gel permeation chromatography-multiple angle laser light scattering and ultrahigh performance liquid chromatography-electrospray-quadrupole/time of flight-mass spectrometry, respectively. The physicochemical properties of selectively oxidized cellulose having different degrees of oxidation were carefully characterized providing a theoretical foundation for the more accurate selection of applications of oxidized celluloses.

11.
Zhong Yao Cai ; 29(5): 462-4, 2006 May.
Artículo en Zh | MEDLINE | ID: mdl-16981460

RESUMEN

OBJECTIVE: To study the effects of different fractions of Modified Zhisousan (MZ, MZC, MZS) on the contents of nitric oxide (NO), endothelin-1 (ET-1) and eosinophilia (EOS) in the allergic asthma guinea pigs and observe the pathology changes of lung tissue. METHODS: The number of EOS in the blood and bronchialveolar lavage fluid (BALF) was counted by Wright staining. The contents of ET-1 and No in serum and BALF were analyzed by RIA and nitric acid reductase method. The guinea pig lungs were observed under the optical and electron microscope. RESULTS: The number of EOS and the contents of ET-1 and NO in model group were higher than those in control group (P < 0.01). The pathological changes of lung were obvious. The number of EOS and the contents of ET-1 and NO were descended remarkably (P < 0.05 or P < 0.01) and the pathological changes in the lung tissue were lightened obviously in MZ and MZC groups, but MZS group had no such effects. CONCLUSION: MZC is the effective part of MZ and the anti-asthmatic mechanisms ware related to its significant reduction in contents of ET-1, NO, EOS and the damage of lung tissue possibly.


Asunto(s)
Antiasmáticos/farmacología , Asma/patología , Medicamentos Herbarios Chinos/farmacología , Pulmón/patología , Animales , Asma/tratamiento farmacológico , Líquido del Lavado Bronquioalveolar/química , Medicamentos Herbarios Chinos/química , Endotelina-1/sangre , Eosinófilos/química , Cobayas , Recuento de Leucocitos , Ratones , Óxido Nítrico/sangre , Polvos
12.
J Ethnopharmacol ; 185: 263-71, 2016 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-26972504

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Eupatorium lindleyanum DC. is widely used for its efficiency in treating cough, tracheitis and tonsillitis. Acute lung injury (ALI) induced by lipopolysaccharide (LPS) in mice was used to investigate therapeutic effects and possible mechanism of the sesquiterpenes fraction of E. lindleyanum DC. (EUP-SQT). MATERIALS AND METHODS: Mice were orally administrated with EUP-SQT (15, 30 and 60mg/kg) per day for 7 days consecutively before LPS challenge. The lung specimens and bronchoalveolar lavage fluid (BALF) were harvested for histopathological examinations and biochemical analysis at 6h and 24h after LPS challenge. The level of complement 3 (C3) and complement 3c (C3c) in serum was quantified by a sandwich ELISA kit. RESULTS: Pretreatment with EUP-SQT could significantly decrease lung wet-to-dry weight (W/D) ratio, nitric oxide (NO) and protein concentration in BALF, which was exhibited together with the lowered myeloperoxidase (MPO) activity, the increased superoxide dismutase (SOD) activity and down-regulation the level of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß) in ALI model. Additionally, EUP-SQT attenuated lung histopathological changes and significantly reduced complement deposition with decreasing the level of C3 and C3c in serum. CONCLUSIONS: These results showed that EUP-SQT significantly attenuated LPS-induced ALI via reducing productions of pro-inflammatory mediators and decreasing the level of complement, indicating it as a potential therapeutic agent for ALI.


Asunto(s)
Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Eupatorium/química , Lipopolisacáridos/toxicidad , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Animales , Líquido del Lavado Bronquioalveolar/química , Citocinas/química , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Extractos Vegetales/química , Sesquiterpenos/química
13.
Carbohydr Polym ; 146: 238-44, 2016 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-27112871

RESUMEN

Oxidized starch, one of the most important starch derivatives, has many different properties and applications. Currently, there are two ways to produce oxidized starch, through specific and nonspecific oxidation. Specific oxidation using the stable nitroxyl radical, 2,2,6,6-tetramethyl preparidinloxy (TEMPO), with NaBr and NaClO can produce oxidized starches with different properties under good quality control. In the current study, we examine the products of specifically oxidized starch. As the amount of oxidant and the temperature, two critical factors impacting the oxidation of starch were thoroughly investigated. Analysis of the molecular weight (MW), degree of oxidization (DO) and the detailed structures of corresponding products was accomplished using gel permeation chromatography with multi-angle laser light scattering (GPC-MALLS), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and quadrapole time-of-flight mass spectrometry (Q/TOF-MS). According to the analytical results, the oxidation patterns of starch treated with specific oxidant TEMPO-NaBr-NaClO were established. When high amounts of oxidant was applied, more glucose residues within starch were oxidized to glucuronic acids (higher DO) and substantial degradation to starch oligosaccharides was observed. By selecting a reaction temperature of 25°C a high DO could be obtained for a given amount of oxidant. The reducing end sugar residue within oxidized starch was itself oxidized and ring opened in all TEMPO-NaBr-NaClO reactions. Furthermore, extra oxidant generated additional novel structures in the reducing end residues of some products, particularly in low temperature reactions.

14.
Chin J Nat Med ; 13(10): 767-75, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26481377

RESUMEN

The present study was designed to evaluate the protective effects of ethanol extracts of Rabdosia japonica var. glaucocalyx (Maxim.) Hara (RJ) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and the possible underlying mechanisms of action. The mice were orally administrated with RJ extract (16, 32 or 64 mg(kg(-1)) daily for consecutive7 days before LPS challenge. The ung specimens and the bronchoalveolar lavage fluid (BALF) were collected for histopathological examinations and biochemical analyses. Pretreatment with RJ significantly enhanced superoxide dismutase (SOD) activity and reduced the wet-to-dry weight (W/D) ratio, the levels of nitric oxide (NO) and protein leakage, and myeloperoxidase (MPO) activity in mice with ALI, in a dose-dependent manner. RJ reduced complement deposition and significantly attenuated LPS-induced ALI by reducing productions of inflammatory mediators, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß). The results demonstrated that RJ may attenuate LPS-induced ALI via reducing the production of pro-inflammatory mediators, and reducing complement deposition and radicals.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Mediadores de Inflamación/metabolismo , Isodon/química , Pulmón/efectos de los fármacos , Fitoterapia , Extractos Vegetales/uso terapéutico , Lesión Pulmonar Aguda/inducido químicamente , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antioxidantes/metabolismo , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Proteínas del Sistema Complemento/metabolismo , Lipopolisacáridos , Pulmón/metabolismo , Masculino , Ratones , Óxido Nítrico/metabolismo , Peroxidasa/metabolismo , Extractos Vegetales/farmacología , Superóxido Dismutasa/metabolismo
15.
J Chromatogr A ; 1423: 79-85, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26530145

RESUMEN

Dextran, a family of natural polysaccharides, consists of an α (1→6) linked-glucose main (backbone) chain having a number of branches. The determination of the types and the quantities of branches in dextran is important in understanding its various biological roles. In this study, a hyphenated method using high-performance anion exchange chromatography (HPAEC) in parallel with pulsed amperometric detection (PAD) and mass spectrometry (MS) was applied to qualitative and quantitative analysis of dextran branches. A rotary cation-exchange cartridge array desalter was used for removal of salt from the HPAEC eluent making it MS compatible. MS and MS/MS were used to provide structural information on the enzymatically prepared dextran oligosaccharides. PAD provides quantitative data on the ratio of enzyme-resistant, branched dextran oligosaccharides. Both the types and degree of branching found in a variety of dextrans could be simultaneously determined online using this method.


Asunto(s)
Cromatografía por Intercambio Iónico , Dextranos/análisis , Dextranos/química , Espectrometría de Masas en Tándem
16.
J Am Soc Mass Spectrom ; 26(7): 1174-85, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25930093

RESUMEN

Investigation of the action pattern of enzymes acting on carbohydrates is challenging, as both the substrate and the digestion products are complex mixtures. Dextran and its enzyme-derived oligosaccharides are widely used for many industrial applications. In this work, a new method relying on ultra-performance hydrophilic interaction liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UP-HILIC-Q/TOF-MS/MS) was developed to analyze a complex mixture of dextran oligosaccharide products to determine the action pattern of dextranase. No derivatization of oligosaccharides was required and the impact of the α- and ß-configurations of the native oligosaccharides on the chromatographic separation was eliminated. The 1→6, 1→3, 1→4 backbone linkages and the branch linkages of these oligosaccharides were all distinguished from diagnostic ions in their MS/MS spectra, including fragments corresponding to (0,2)A, (0,3)A, (0,4)A, B-H2O, (2,5)A, and (3,5)A. The sequences of the oligosaccharide products were similarly established. Thus, the complex oligosaccharide mixtures in dextran digestion products were profiled and identified using this method. The more enzyme-resistant structures in dextran were established using much less sample, labor, time, and uncertainty than in previous studies. This method provides an efficient, sensitive, and straightforward way to monitor the entire process of digestion, establish the action pattern of the dextranase from Penicillium sp., and to support the proper industrial application of dextranase.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dextranasa/metabolismo , Dextranos/química , Dextranos/metabolismo , Penicillium/enzimología , Espectrometría de Masas en Tándem/métodos , Dextranos/análisis , Interacciones Hidrofóbicas e Hidrofílicas
17.
Carbohydr Polym ; 122: 180-8, 2015 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-25817657

RESUMEN

Alginate is a linear and acidic polysaccharide, composed of (1 → 4) linked ß-D-mannuronic acid (ManA) and α-L-guluronic acid (GulA). The ratio of ManA to GulA (M/G) is one of the most important factors for the application of alginate and its derivatives in various areas. In this work, a robust and accurate method was developed to analyze M/G using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The impact of hydrolysis conditions on the release patterns of ManA and GulA from alginate and its derivatives was investigated. The release patterns of ManA and GulA need to be considered separately to obtain an accurate M/G. Several hydrolysis conditions were established that released ManA and GulA completely and maintained these saccharide residues intact. The proper M/G of alginates from different sources and its derivatives could then be calculated by integration of the corresponding ManA and GulA peaks.


Asunto(s)
Alginatos/química , Ácidos Hexurónicos/análisis , Hidrólisis , Espectroscopía de Resonancia Magnética
18.
Artículo en Inglés | MEDLINE | ID: mdl-25013450

RESUMEN

Rabdosia japonica var. glaucocalyx (Maxim.) Hara, belonging to the Labiatae family, is widely used as an anti-inflammatory and antitumor drug for the treatment of different inflammations and cancers. Aim of the Study. To investigate therapeutic effects and possible mechanism of the flavonoids fraction of Rabdosia japonica var. glaucocalyx (Maxim.) Hara (RJFs) in acute lung injury (ALI) mice induced by lipopolysaccharide (LPS). Materials and Methods. Mice were orally administrated with RJFs (6.4, 12.8, and 25.6 mg/kg) per day for 7 days, consecutively, before LPS challenge. Lung specimens and the bronchoalveolar lavage fluid (BALF) were isolated for histopathological examinations and biochemical analysis. The level of complement 3 (C3) in serum was quantified by a sandwich ELISA kit. Results. RJFs significantly attenuated LPS-induced ALI via reducing productions of the level of inflammatory mediators (TNF- α , IL-6, and IL-1 ß ), and significantly reduced complement deposition with decreasing the level of C3 in serum, which was exhibited together with the lowered myeloperoxidase (MPO) activity and nitric oxide (NO) and protein concentration in BALF. Conclusions. RJFs significantly attenuate LPS-induced ALI via reducing productions of proinflammatory mediators, decreasing the level of complement, and reducing radicals.

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