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1.
Toxicol Res (Camb) ; 5(2): 399-406, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30090355

RESUMO

In the present study, the potential effects of 2-allyl amino 4-methyl sulfanyl butyric acid (AMSB) on the glucose metabolism and glycoprotein components in streptozotocin (STZ) induced experimental diabetic rats were determined. Further, molecular modeling was performed to investigate the modes of AMSB interaction with insulin receptor active sites. The blood glucose and plasma insulin levels were measured in the STZ induced diabetic rats, whereas the glucose metabolism and glycoprotein components were analyzed from the plasma and tissues. After oral treatment of AMSB there was a significant reduction in blood glucose, glucose-6-phosphatase, fructose-1,6-bisphosphatase and glycogen phosphorylase. On the other hand, the activity of the glycoprotein levels, such as hexose, hexosamine, fucose and sialic acid, were significantly reduced. In addition, a significant elevation in plasma insulin, hexokinase, glycogen and glycogen synthase were also observed in the AMSB treated rats. The molecular modeling study revealed that AMSB has a stable binding pattern to the active site of insulin, with a Gscore value of -7.34 Kcal mol-1. From this study we conclude that AMSB has a potent antidiabetic activity in addition to its protective effect on glycoprotein metabolism.

2.
J Hazard Mater ; 272: 89-95, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24681590

RESUMO

The effluent discharge treatment for controlling the environment from non biodegradable metal contaminants using plant extract is an efficient technique. The reduction of hexavalent chromium by abundantly available weed, Aerva lanata L. was investigated using batch equilibrium technique. The variables studied were Cr(VI) concentration, Aerva lanata L. dose, contact time, pH, temperature and agitation speed. Cyclic voltammetry and ICP-MS analysis confirmed the reduction of Cr(VI) to Cr(III). Electrochemical analysis proved that, the chromium has not been degraded and the valency of the chromium has only been changed. ICP-MS analysis shows that 100ng/L of hexavalent chromium was reduced to 97.01ng/L trivalent chromium. These results suggest that components present in the Aerva lanata L. are responsible for the reduction of Cr(VI) to Cr(III). The prime components ferulic acid, kaempherol and ß-carboline present in the Aerva lanata L. may be responsible for the reduction of Cr(VI) as evident from LC-MS analysis.


Assuntos
Amaranthaceae/metabolismo , Cromo/análise , Carbolinas/química , Cromatografia Líquida , Cromo/química , Ácidos Cumáricos/química , Eletroquímica , Concentração de Íons de Hidrogênio , Resíduos Industriais , Quempferóis/química , Espectrometria de Massas/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos
3.
Prep Biochem Biotechnol ; 43(7): 649-67, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23768111

RESUMO

Pseudomonas oleovorans PAMD_1 produced an intracellular azoreductase as the more prominent enzyme that reduces the azo bridge during the azo dye decolorization process. In order to optimize the expression of azoreductase, statistically based experiments were applied. Eleven significant factors were screened on decolorization activity using Plackett-Burman design. Dye, NADH, glucose, and peptone were identified as having highest positive influence on the decolorization activity. Central composite design of response surface methodology was employed for the concerted effect of these four factors on decolorization activity. This method showed that the optimum medium containing dye (200 mg L(-1)), NADH (1.14 mM), glucose (2.07 g L(-1)), and peptone (6.44 g L(-1)) for the decolorization of Orange II up to 87% in 48 hr. The applied methodology was validated through the adequacy and accuracy of the overall experiments, and the results proved that the applied methods were most effective. Further, the enzyme was purified ninefold with 16% yield by anion-exchange chromatography and a specific activity of 26 U mg(-1). The purified enzyme with a molecular mass of 29,000 Da gave a single band on sodium dodecyl sulfate (SDS) gel, and the degradation products sulfanilic acid and 1-amino-2-napthol of Orange II by azoreductase were analyzed by using an ultraviolet-visible (UV-Vis) spectrophotometer and hish-performance liquid chromatography (HPLC).


Assuntos
Biodegradação Ambiental , NADH NADPH Oxirredutases/química , NADH NADPH Oxirredutases/isolamento & purificação , Pseudomonas oleovorans/enzimologia , Compostos Azo/síntese química , Compostos Azo/química , Benzenossulfonatos/síntese química , Benzenossulfonatos/química , Corantes/química , Corantes/isolamento & purificação , Humanos , Cinética , NADH NADPH Oxirredutases/metabolismo , Nitrorredutases
4.
J Hazard Mater ; 186(1): 827-34, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21232849

RESUMO

Thespesia populnea is a large tree found in the tropical regions and coastal forests of India. Its pods were used as a raw material for the preparation of activated carbon. The prepared activated carbon was used for the adsorptive removal of Orange G dye from aqueous system. The effects of various parameters such as agitation time, initial dye concentration and adsorbent dosage were studied using response surface methodology (RSM). RSM results show that 0.54 g of activated carbon was required for the maximum adsorption of Orange G dye (17.6 mg L(-1)) within a time period of 4.03 h. Adsorption data were modeled using Freundlich and Langmuir adsorption isotherms. The adsorption of Orange G dye by activated carbon obeyed both Fruendlich and Langmuir isotherm. Adsorption kinetic data were tested using pseudo-zero, first, second-order and intraparticle diffusion models. Kinetic studies revealed that the adsorption followed pseudo-second-order reaction with regard to the intraparticle diffusion. FTIR spectral result indicated all the functional group except primary amines (3417 cm(-1)) and CN (1618 cm(-1)) were involved in the adsorption process. XRD data showed that Orange G dye adsorbed activated carbon might not induce the bulk phase changes. SEM results showed that the surface of the activated carbon was turned from dark to light color after dye adsorption.


Assuntos
Compostos Azo/química , Corantes/química , Malvaceae/química , Adsorção , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
5.
J Basic Microbiol ; 50(4): 360-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20586068

RESUMO

Pleurotus florida NCIM 1243 produced laccase as the dominant lignolytic enzyme during the dye decolorization. Banana peel was the best substrate for extracellular laccase production under solid state fermentation when compared to mandarin peel and cantaloupe peel. The maximum activity of laccase (5.4 U/g) was detected on the 10 day. The ratio of banana peel: mandarin peel: cantaloupe peel (5:2:3) showed increased production of laccase (6.8 U/g). P. florida produced two extracellular laccase isoenzymes (L1 and L2). The half life of laccase at 60 degrees C was 2 h and at 4 h it retained 25% residual activity. P. florida laccase showed high thermostability and an interesting difference was noticed in the behavior of laccase isoenzymes at different temperature. The L1 isoenzyme of laccase showed remarked thermostability at 60 degrees C in the native PAGE when compared to L2 isoenzyme. The optimum pH, temperature and enzyme concentration for maximum decolorization was found to be 4.5, 60 degrees C and 1.2 U/ml, respectively. Partially purified laccase enzyme showed excellent decolorization activity to Reactive blue 198. The maximum decolorization (96%) was observed at lower dye concentrations (50-100 ppm) which decreased markedly when the dye concentration was increased beyond 150 ppm. The thermostable laccase of P. florida could be effectively used to decolorize the synthetic dyes in the textile effluent and other biotechnological applications.


Assuntos
Corantes/metabolismo , Fermentação , Microbiologia Industrial , Lacase/biossíntese , Pleurotus/enzimologia , Biodegradação Ambiental , Frutas/metabolismo , Eliminação de Resíduos Líquidos
6.
J Basic Microbiol ; 50(4): 325-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20473960

RESUMO

Statistically-based experimental designs were applied to optimize the fermentation for the production of laccase by Pleurotus florida NCIM 1243. Eleven components were screened for their significant effect on laccase production using Plackett-Burman factorial design. Glucose (carbon source), asparagine (nitrogen source), CuSO(4)(inducer) and incubation period were found to have highest positive influence on the laccase production. The combined effect of these factors on laccase production was studied using central composite design of Response surface methodology. The optimal point of variables for maximum laccase production using Response surface methodology are glucose (15.21 g/l), asparagine (6.40 g/l), CuSO(4) (91.78 microM) and incubation period (178.55 h), respectively. The maximum enzyme activity predicted by the model was 5.0 U/ml which was in perfect agreement with the actual experimental value (4.8 U/ml). Further, partially purified laccase from the optimized cultural condition was used for the decolorization of reactive dyes, Reactive Blue 198 and Reactive Red 35.


Assuntos
Fermentação , Microbiologia Industrial , Lacase/biossíntese , Pleurotus/enzimologia , Corantes/metabolismo , Meios de Cultura
7.
Indian J Biochem Biophys ; 47(6): 364-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21355420

RESUMO

CREB binding protein (CBP) and E1A binding protein p300, also known as p300 are functionally related transcriptional co-activators (CoAs) and histone acetyltransferases (HATs). Some small molecules, which target HATs can activate or inhibit the p300 enzyme potently. Here, we report the binding affinities of two small molecules CTPB [N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide] and CTB [N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxybenzamide] with p300 using docking method to obtain the insight of their interaction with p300. These small molecules bind to the enzyme, subsequently causing a structural change in the enzyme, which is responsible for the HAT activation. CTB exhibits higher binding affinity than CTPB, and their lowest docked energies are -7.72, -1.18 kcal/mol, respectively. In CTPB molecule, phenolic hydroxyl of Tyr1397 interacts with the non-polar atoms C(5E) and C(5F), and forms polar-non polar interactions. Similar interactions have also been observed in CTB. The residues Tyr1446 and Cys1438 interact with the non-pentadecyl atoms. Further, the docking study predicts a N-H--O hydrogen bonding interaction between CTB and Leu1398, in which the H--O contact distance is 2.06 A. The long pentadecyl chain of CTPB reduces the formation of hydrogen bond with the p300. The H-bond interaction could be the key factor for the better activation of CTB.


Assuntos
Benzamidas/metabolismo , Benzamidas/farmacologia , Fatores de Transcrição de p300-CBP/química , Fatores de Transcrição de p300-CBP/metabolismo , Sítios de Ligação , Domínio Catalítico , Ativação Enzimática , Humanos , Técnicas In Vitro , Ligantes , Modelos Moleculares
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