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1.
Acta Chim Slov ; 69(3): 596-603, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36196819

RESUMO

A new two-dimensional coordinate polymer, {[Zn2(pbmpd)(H2O)4]·(H2O)}n (H4pbmpd = 1,1'-(1,4-phenylenebis(methylene))bis-(1H-pyrazole-3,5-dicarboxylic acid)), has been hydrothermally synthesized and characterized by IR spectrum, elemental analysis,TGA and X-ray single-crystal/powder diffraction. Structural analyses reveal that complex 1 exhibits a two-dimensional sheet structure in the crystal lattice. In complex 1, the carboxylic oxygen atoms and conjugated N atoms of pbmpd4- bridge zinc(II) ions form indefinitely zigzag shaped one-dimensional chains through p···p stacking interactions which are further connected by [ZnO6] units to form a novel two-dimensional structure. Finally, p···p stacking interactions and intermolecular hydrogen bonds assemble the two dimensional networks into a three-dimensional framework. Furthermore, the luminescent properties are also discussed. Interestingly, the solid state photoluminescence properties of the title polymer show the enhancement effect of spectrum. Density functional theory (DFT) calculations were used to support the experimental data.

2.
Appl Biochem Biotechnol ; 179(8): 1325-35, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27075456

RESUMO

In this study, enzyme-assisted three-phase partitioning (EATPP) was used to extract oil from flaxseed. The whole procedure is composed of two parts: the enzymolysis procedure in which the flaxseed was hydrolyzed using an enzyme solution (the influencing parameters such as the type and concentration of enzyme, temperature, and pH were optimized) and three-phase partitioning (TPP), which was conducted by adding salt and t-butanol to the crude flaxseed slurry, resulting in the extraction of flaxseed oil into alcohol-rich upper phase. The concentration of t-butanol, concentration of salt, and the temperature were optimized to maximize the extraction yield. Under optimized conditions of a 49.29 % t-butanol concentration, 30.43 % ammonium sulfate concentration, and 35 °C extraction temperature, a maximum extraction yield of 71.68 % was obtained. This simple and effective EATPP can be used to achieve high extraction yields and oil quality, and thus, it is potential for large-scale oil production.


Assuntos
Fracionamento Químico/métodos , Linho/química , Óleo de Semente do Linho/isolamento & purificação , Peptídeo Hidrolases/metabolismo , Poligalacturonase/metabolismo , Sulfato de Amônio/química , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Temperatura , terc-Butil Álcool/química
3.
Molecules ; 20(10): 17929-43, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26437389

RESUMO

In this work, a two-step extraction methodology of ionic liquid-based ultrasonic-assisted extraction (IL-UAE) and ionic liquid-based aqueous two-phase system (IL-ATPS) was developed for the extraction and purification of secoisolariciresinol diglucoside (SDG) from flaxseed. In the IL-UAE step, several kinds of ILs were investigated as the extractants, to identify the IL that affords the optimum extraction yield. The extraction conditions such as IL concentration, ultrasonic irradiation time, and liquid-solid ratio were optimized using response surface methodology (RSM). In the IL-ATPS step, ATPS formed by adding kosmotropic salts to the IL extract was used for further separation and purification of SDG. The most influential parameters (type and concentration of salt, temperature, and pH) were investigated to obtain the optimum extraction efficiency. The maximum extraction efficiency was 93.35% under the optimal conditions of 45.86% (w/w) IL and 8.27% (w/w) Na2SO4 at 22 °C and pH 11.0. Thus, the combination of IL-UAE and IL-ATPS makes up a simple and effective methodology for the extraction and purification of SDG. This process is also expected to be highly useful for the extraction and purification of bioactive compounds from other important medicinal plants.


Assuntos
Butileno Glicóis/química , Butileno Glicóis/isolamento & purificação , Linho/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Extração Líquido-Líquido , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ondas Ultrassônicas , Análise de Variância , Concentração de Íons de Hidrogênio , Extração Líquido-Líquido/métodos , Sais , Temperatura
4.
J Hazard Mater ; 292: 9-18, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25781371

RESUMO

A series of visible-light responsive photocatalysts prepared using Ag3PO4 immobilized with graphene oxide (GO) with varying GO content were obtained by an electrostatically driven method, and 2,4-dichlorophenol (2,4-DCP) was used to evaluate the performance of the photocatalysts. The composites exhibited superior photocatalytic activity and stability compared with pure Ag3PO4. When the content of GO was 5%, the degradation efficiency of 2,4-DCP could reach 98.95%, and 55.91% of the total organic (TOC) content was removed within 60 min irradiation. Meanwhile, the efficiency of 91.77% was achieved for 2,4-DCP degradation even after four times of recycling in the photocatalysis/Ag3PO4-GO (5%) system. Reactive species of O2(˙-), OH˙ and h(+) were considered as the main participants for oxidizing 2,4-DCP, as confirmed by the free radical capture experiments. And some organic intermediates including 4-chlorophenol (4-CP), hydroquinone (HQ), benzoquinone (BZQ), 2-chlorohydroquinone and hydroxyhydroquinone (HHQ) were detected by comparison with the standard retention times from the high performance liquid chromatography (HPLC). In short, the enhanced photocatalytic property of Ag3PO4-GO was closely related to the strong absorption ability of GO relative to 2,4-DCP, the effective separation of photogenerated electron-hole pairs, and the excellent electron capture capability of GO.


Assuntos
Clorofenóis/química , Grafite/química , Luz , Fosfatos/química , Compostos de Prata/química , Catálise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óxidos/química , Processos Fotoquímicos , Espectrometria por Raios X
5.
Artigo em Inglês | MEDLINE | ID: mdl-23246229

RESUMO

OBJECTIVE: Recurrent aphthous stomatitis (RAS) is a common oral mucosal disease, yet effective therapeutic approaches are lacking. This study aimed to determine the effects of application of berberine gelatin in the treatment of minor RAS (MiRAS). METHODS: A randomized, double-blind, placebo-controlled, clinical trial was performed. The gelatin containing berberine (5 mg/g) or vehicle only was applied 4 times per day for 5 days. Clinical evaluation included pain level, size, erythema, and exudation of certain ulcers on days 1, 2, 4, and 6. RESULTS: A total of 84 subjects fulfilled the study without obvious side effects. Berberine gelatin treatment reduced the ulcer pain score compared with placebo gelatin (P < 0.05). Ulcer size was significantly reduced (P < 0.05) and lower erythema (P < 0.05) and exudation (P < 0.05) levels were associated with berberine treatment. CONCLUSIONS: Berberine gelatin may be a safe and effective treatment for MiRAS.


Assuntos
Berberina/uso terapêutico , Gelatina/uso terapêutico , Estomatite Aftosa/tratamento farmacológico , Administração Tópica , Adulto , Berberina/administração & dosagem , Distribuição de Qui-Quadrado , China , Método Duplo-Cego , Feminino , Gelatina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Placebos , Recidiva , Estatísticas não Paramétricas , Resultado do Tratamento
6.
Bioprocess Biosyst Eng ; 36(8): 1105-13, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23207826

RESUMO

An alcohol/salt aqueous two-phase system (ATPS) composed of 1-propanol and (NH4)2SO4 was employed to purify anthraquinones (AQs) extracted from Aloe vera L. The main influencing system parameters such as type of alcohol, type and concentration of salt, temperature and pH were investigated in detail. Under the optimal extraction conditions, AQs can be extracted into alcohol-rich phase with high extraction efficiency, meanwhile majority polysaccharides, proteins, mineral substances and other impurities were extracted into salt-rich phase. Partitioning of AQs is dependent on hydrophobic interaction, hydrogen bond interaction, and salting-out effect in ATPS. Temperature also played a great role in the partitioning. After ATPS extraction, alcohol can be recycled by evaporation; moreover, salt can be recycled by dilution crystallization method. Compared with other liquid-liquid extractions, this alcohol/salt system is much simpler, lower in cost with easier recovery of phase-forming components, which has the potential scale-up in down-processing of active ingredients in plant.


Assuntos
Aloe/metabolismo , Antraquinonas/isolamento & purificação , Álcoois/química , Antraquinonas/química , Cristalização , Emodina/química , Etanol/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Extração Líquido-Líquido , Metanol/química , Extratos Vegetais/química , Sais/química , Temperatura , Termodinâmica , Viscosidade
7.
Artigo em Inglês | MEDLINE | ID: mdl-22668427

RESUMO

OBJECTIVE: We investigated the effectiveness and safety of topical application of 5 mg allicin adhesive tablets in the treatment of minor recurrent aphthous ulcerations (MiRAU). MATERIAL AND METHODS: A randomized, double-blinded, placebo-controlled, clinical trial was performed. Tablets containing 5 mg allicin or vehicle only were consecutively applied 4 times per day for 5 days. The size and pain level of ulcers were measured and recorded on days 1, 2, 4, and 6. RESULTS: A total of 96 subjects with MiRAU fulfilled the study. Allicin adhesive tablets significantly reduced ulcer size (P < .005, P < .003, P < .001 for days 2, 4, and 6, respectively) and alleviated ulcer pain score (P < .03, P < .001, P < .05 for days 2, 4, and 6, respectively) compared with vehicle tablets. Minor and major adverse reactions were not observed. CONCLUSIONS: Allicin adhesive tablets were effective in reducing ulcer size and alleviating ulcer pain of the patients in the treatment of MiRAU without significant side effects.


Assuntos
Adesivos/uso terapêutico , Estomatite Aftosa/tratamento farmacológico , Ácidos Sulfínicos/uso terapêutico , Adolescente , Adulto , Distribuição de Qui-Quadrado , Dissulfetos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Comprimidos , Resultado do Tratamento , Adulto Jovem
8.
Nat Prod Res ; 26(15): 1423-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22007923

RESUMO

Non-ionic surfactant-based aqueous two-phase system had been investigated to extract aloe anthraquinones. It had the advantage of using a single auxiliary chemical to induce phase separation above cloud point at a low concentration. Non-ionic surfactant Triton X-114 was chosen for its excellent phase-separating ability and low cloud point. The main factors affecting the cloud point extraction were discussed such as equilibrium temperature and time, concentrations of surfactant and inorganic electrolytes, pH, etc. Under the optimised conditions, the highest extraction yield 96.93% was obtained. The reverse extraction of anthraquinones from surfactant-rich phase was achieved with a recovery of 70.35% by adjusting pH. Compared with conventional purification methods, this CPE technique can be completed in one operation; besides, it is a low-cost method and an environment friendly one.


Assuntos
Aloe/química , Antraquinonas/química , Tensoativos/química , Octoxinol , Polietilenoglicóis/química
9.
Nat Prod Res ; 23(15): 1424-30, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19809915

RESUMO

A PEG6000/(NH4)2SO4 aqueous two-phase system was chosen as the separation system. The effects of NaCl, Gu(SCN)2 and pH on the partitioning of aloe polysaccharide and bovine serum albumin (BSA) were studied. The result shows that the recovery of aloe polysaccharide was decreased with the increase in pH and the recovery of protein was not changed; NaCl and Gu(SCN)2 can change the partitioning behaviour of the BSA. The separation of BSA and aloe polysaccharides was also carried out. Then, the aloe polysaccharides were obtained by using ultrafiltration membrane. The composition of the polysaccharides was analysed by gas chromatography. The results show that mannose is mainly monosaccharide, and it only contains a few glucose.


Assuntos
Aloe/química , Fracionamento Químico/métodos , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Estrutura Molecular
10.
Nat Prod Commun ; 4(8): 1093-4, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19768990

RESUMO

A two-step process has been developed for the purification of nicotine from waste tobacco using an aqueous two-phase system and solvent reverse extraction. The partitioning behavior of nicotine was investigated in an isopropyl alcohol/(NH4)2SO4 aqueous two-phase system. The effects of the addition of salt, pH and temperature on the partitioning behavior of nicotine were studied. The recovery rate of nicotine was 96.1% with a purity of above 99% when optimal conditions were used [(NH4)2SO4 25%, pH 9, temperature 35 degrees C, isopropyl alcohol 5 mL].


Assuntos
Nicotiana/química , Nicotina/isolamento & purificação , 2-Propanol , Sulfato de Amônio , Concentração de Íons de Hidrogênio , Cinética , Resíduos/análise
11.
Appl Biochem Biotechnol ; 158(1): 11-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19415529

RESUMO

A two-step process was developed for the purification of polysaccharides from the pulp of Aloe varavia using aqueous two-phase system (ATPS) extraction and a novel copolymer ultrafiltration membrane. The first step was ATPS under optimal separations conditions using a total composition of 18% PEG2000, 25% ammonium sulfate, pH 3.0, and 0.3 M NaCl. To form the copolymer membrane, poly(acrylonitrile-acrylamide-styrene) was prepared by solution polycondensation using azoisobutyronitrile as initiator. Then, membranes were formed from the dissolved copolymer by the phase inversion method. Copolymer structure was investigated by infrared spectrum and thermogravimetric analysis (TGA). The copolymer membrane surface and cross section were observed by scanning electron microscopy. The water flux of this membrane was 26.33 mL/(cm(2) h), and retention was 96% for bovine serum albumin and 34% for dextran T40000. The separation and purification of aloe polysaccharide were carried using this copolymer membrane following ATPS. The TGA of aloe polysaccharide demonstrated a high purity of the polysaccharide. By gas chromatographic analysis, it was shown that mannose is the main monosaccharide in the aloe polysaccharide, and only a few glucose residues are present.


Assuntos
Aloe/química , Fracionamento Químico/métodos , Membranas Artificiais , Polissacarídeos/isolamento & purificação , Água/química , Resinas Acrílicas/análise , Resinas Acrílicas/química , Polissacarídeos/análise , Poliestirenos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Ultrafiltração
12.
Huan Jing Ke Xue ; 26(2): 88-92, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16004306

RESUMO

Parallel laboratory experiments were conducted to investigate the performance of thermophilic and mesophilic anaerobic sequencing batch reactor (ASBR) for the digestion of thermo-hydrolyzed sewage sludge. The average total COD (TCOD) removal rates of thermophilic, mesophilic ASBR at 10-day HRT and 5.42 kg/(m3 x d) TCOD loading rate were 56.20% and 61.66%, and the biogas production rates of TCOD in feeding sludge were 199 and 219 mL/g, respectively. ASBR has the unique capability of maintaining high-solid content and keeping a high solid retention time (SRT). The average SRT of thermophilic, mesophilic ASBR were 30 and 37d, respectively. Compared to mesophilic ASBR, thermophilic ASBR show considerably fewer microbial morphologies and lower methane-production, which might result in a relatively lower treatment efficiency in thermophilic ASBR than that in mesophilic ASBR.


Assuntos
Bactérias Aeróbias/metabolismo , Temperatura Alta , Esgotos/análise , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Reatores Biológicos , Temperatura , Eliminação de Resíduos Líquidos/instrumentação
13.
Zhonghua Yi Xue Za Zhi ; 84(18): 1562-6, 2004 Sep 17.
Artigo em Chinês | MEDLINE | ID: mdl-15500722

RESUMO

OBJECTIVE: To determine the effect of anterior chamber associated immune deviation (ACAID) on endotoxin-induced uveitis (EIU) and the possible mechanism. METHODS: ACAID animal model was induced by injection of 5 microl IRBP (10 microg/microl) into the anterior chamber (AC) of Spar-Dawley (SD) rats. Then 200 microg LPS was injected into hind footpads at different time points after AC inoculation. The animals were randomly divided into 3 groups: positive control (LPS injection only), 3 d group (LPS injection 3 days after IRBP inoculation), 7 d group (LPS injection 7 days after IRBP inoculation). Delayed type hypersensitivity (DTH) was examined to determine the development of ACAID. Then the serum level of IL-10 was evaluated by ELISA, and GATA-3 expression at the different time points after IRBP injection was assayed by reverse transcription polymerase chain reaction (RT-PCR) and Western blot on mRNA and protein level respectively. The ocular inflammation was observed clinically; at the same time, the eye was extirpated and histological examination was performed. RESULTS: In control and 3 d groups, significant DTH reaction was induced, but the serum level of IL-10 could not be detected and GATA-3 expression was not increased. While in 7 d group, the DTH reaction could not be induced, and IL-10 and GATA-3 expression increased significantly at both the mRNA and protein levels. The clinical manifestation was significantly alleviated in the 7 d group; Histological examination displayed that the inflammatory cells were significantly reduced in iris/ciliary body, anterior and posterior chambers, vitreous body and retina of the rats in 7 d group. CONCLUSION: The development of ACAID can reduce the ocular inflammation induced by LPS, that is related to the increase of GATA-3 and IL-10 expression.


Assuntos
Câmara Anterior/imunologia , Proteínas de Ligação a DNA/metabolismo , Proteínas do Olho/imunologia , Proteínas de Ligação ao Retinol/imunologia , Uveíte/imunologia , Animais , Humor Aquoso/metabolismo , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Endotoxinas , Fator de Transcrição GATA3 , Hipersensibilidade Tardia/imunologia , Interleucina-10/sangue , Masculino , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transativadores/biossíntese , Transativadores/genética , Uveíte/induzido quimicamente
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