RESUMO
The main cause of hepatitis C is hepatitis C virus or HCV and for the cure of hepatitis C, NS3/4A protease has been found an important and emerging target. A number of HCV NS3/4A protease inhibitors have been discovered which have shown subsequent reduction in reducing the viral load leading to this infection however they are still undergoing clinical trials for improvement. Bacterial proteases are of great pharmaceutical importance and have a key role in various biological processes and in life cycle of several pathogens. The current study was planned to explore hexapeptides derived from conserved regions of bacterial proteases for their potential in blocking the NS3 protease activity of HCV which would finally inhibit HCV multiplication. For this, a novel protease gene nprB was isolated from a thermophilic bacterium Streptomyces thermovulgaris and bioinformatics analyses were performed. PCR amplification and sequencing of nprB gene indicated an open reading frame of 178 aa (20191.18 Dalton).The peptide GGVHIN was the top ranked with minimum S-score of -17.21) followed by hexapeptides VDAHAN, GVGREA, GALNES and VHINSS with their S-scores of -14.73, -13.78, -10.72 and -10.70, respectively. A phylogram was also reconstructed to reveal evolutionary relationships of nprB with its various homologs. The provided data will serve as a background to further reveal pharmaceutical and biotechnological importance of this novel protease gene from S. thermovulgaris in future.
Assuntos
Proteínas de Bactérias/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Metaloendopeptidases/metabolismo , Peptídeos/metabolismo , Inibidores de Proteases/metabolismo , Streptomyces/genética , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Antivirais/metabolismo , Antivirais/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Sequência Conservada , Metaloendopeptidases/genética , Metaloendopeptidases/farmacologia , Simulação de Acoplamento Molecular , Peptídeos/genética , Peptídeos/farmacologia , Inibidores de Proteases/farmacologiaRESUMO
Bacterial proteases are of great pharmaceutical importance and have a key role in various biological processes and in life cycle of several pathogens. New technology used for rational protein engineering as well improved delivery options will expand the potential pharmaceutical applications of proteases. The catalytic proteases belong to metalloproteases (EC.3.4.24) that comprise thermo lysine. The metalloproteases and their homologs have many important biotechnological and therapeutic applications. In the present study, a novel protease gene nprB was isolated from a thermophilic bacterium Streptomyces thermovulgaris and bioinformatics analyses were performed. PCR amplification and sequencing of nprB gene indicated an open reading frame of 178 aa (20191.18 Dalton). Based on protein sequence homology as well as conserved motifs and PTF domain the protein is characterized as a thermo lysine-like protease and is a member of M4 family of metalloproteases. Different bioinformatics tools such as ProtParam, SOPMA, signalP4.1 and ProDom from the ExPAsy server were used for structural and functional analyses. A phylogram was also reconstructed to reveal evolutionary relationships of nprB with its various homologs. The provided data will serve as a background to further reveal pharmaceutical and biotechnological importance of this novel protease gene from S. thermovulgaris in future.
Assuntos
Proteínas de Bactérias/metabolismo , Metaloproteases/farmacologia , Streptomyces/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Biologia Computacional , Estabilidade Enzimática , Metaloproteases/genética , Metaloproteases/isolamento & purificação , Modelos Moleculares , Filogenia , Conformação Proteica , Streptomyces/genética , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
Effect of solvent polarity and extraction time on antioxidant properties of Brassica oleracea seeds was optimized by response surface methodology using central composite design. A significant linear negative effect of solvent polarity on total extractable components (TEC), total phenolic acids (TPA), linoleic acid reduction capacity (LARC) and hydroxyl radical scavenging capacity (HRSC) and significant positive effect on iron chelating activity (ICA), reducing power (RP) and (DPPH RSC). Linear effect of solvent polarity on total antioxidant activity (TAOA) was also found to be positive but not significant. Significant linear negative effect of extraction time was observed on ICA and HRSC. Only RP was found to be significantly increased with increase in extraction time. Quadratic effect of solvent polarity was found to be negative on TAOA, DPPH RSC and HRSC. However, quadratic effects of both variables were found to be positive on TEC, TPA, ICA and LARC. The polarity dependent increase in TAOA indicates the extraction of phytochemicals with comparatively stronger antioxidant properties in polar solvents. The decrease in antioxidant properties in response to increase in extraction time may be attributed to the time dependent loss of antioxidant activity of extracted compounds.
Assuntos
Antioxidantes/química , Brassica , Extratos Vegetais/química , Sementes , Solventes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extração em Fase Sólida/métodos , Solventes/farmacologiaRESUMO
Zinc oxide nanoparticles (ZnO NPs) have diverse utility these days ranging from being part of nanosensors to be ingredient of cosmetics. Present study was designed to report the effect of variable doses of ZnO NPs on selected aspects of male albino mice behavior. Nano particles were synthesized by sol-gel auto-combustion method (Data not shown here). 10 week old male albino mice were divided into four experimental groups; group A, B and C were orally supplemented with 50 (low dose), 300 (medium dose) and 600 mg/ml solvent/kg body weight (high dose) of ZnO NPs for 4 days. Group D (control) orally received 0.2 M sodium phosphate buffer (solvent for ZnO NPs) for the same duration. A series of neurological tests (Rota rod, open field, novel object and light-dark box test) were conducted in all groups and performance was compared between ZnO NPs treated and control group. Muscular functioning during rota rod test was significantly improved in all ZnO NPs treated mice as compared to control group. While no significant differences in open field, novel object and light-dark box test performance were observed when data from studied parameters of specific ZnO NPs treatment were compared with the control group indicating that applied doses of ZnO NPs did not affect the exploratory, anxiolytic behavior and object recognition capability of adult male albino mice.
Assuntos
Comportamento Exploratório/efeitos dos fármacos , Nanopartículas/administração & dosagem , Reconhecimento Psicológico/efeitos dos fármacos , Óxido de Zinco/farmacologia , Animais , Relação Dose-Resposta a Droga , Comportamento Exploratório/fisiologia , Masculino , Camundongos , Reconhecimento Psicológico/fisiologia , Resultado do TratamentoRESUMO
Effects of extraction time and solvent polarity on antioxidant properties of Brassica oleracea leaves were optimized by response surface methodology using a central composite design. Five extraction times (12, 24, 36, 48 and 60h) and solvent polarities (dipole moment - hexane: 0.0, diethyl ether: 2.80, ethyl acetate: 4.40, methanol: 5.10 and water: 9.0D) were selected for optimization. Response surface analysis of data showed a significant increase (p<0.05) in extract yield and antioxidant potential, based on total phenolic acids, reducing abilities and free radical scavenging capacities, in response to an increase in extraction time and solvent polarity. The optimal response was obtained using relatively polar solvents (4.40-9.00D) and prolonged extraction times (50-60h). This suggests that most of the phytochemical constituents of B. oleracea leaves are polar and possess strong antioxidant potential.
Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Brassica/química , Fracionamento Químico/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Solventes/químicaRESUMO
The present study aimed to investigate the influence of microwave irradiation on the physical and functional properties of starch extracted from Nelumbo nucifera seed flour. The seed flour was obtained by manual grinding of seeds and irradiated at different microwave treatment time, i.e., 1, 2, 3, 4 and 5min at the low-medium intensity. The starch was extracted in distilled water and dried at room temperature using a vacuum desiccator. The morphology, crystal structure, and surface parameters of starch granules were analyzed using scanning electron microscopy, X-ray diffraction, Fourier transform infra-red spectroscopy and Brunauer, Emmett and Teller surface analysis techniques. The functional properties of starch were also determined in terms of water and oil holding capacity, swelling capacity, emulsifying activity and gelling ability. Evidently, crystallinity, surface area and pore volume of starch granules were found to be increased, while particle size and average pore size were decreased as a function of microwave treatment time. The microwave-induced variations in physical parameters significantly affected the functional properties of starch. A significant (p>0.05) exponential decrease in extraction yield and gelling ability, while an exponential increase in the functional properties of starch with increase in the microwave treatment time (R2=0.915-0.985) was recorded.
Assuntos
Farinha , Temperatura Alta , Micro-Ondas , Nelumbo/química , Sementes/química , Amido/química , Amido/isolamento & purificação , Manipulação de Alimentos , Solubilidade , Propriedades de SuperfícieRESUMO
Induction of hyperbilirubinemia in experimental rabbits by phenylhydrazine was optimized in terms of dose, dose interval and number of doses using response surface methodology. Central Composite Design was employed using five levels for each of the three input variables. Degree of hyperbilirubinemia was measured in terms of bilirubin level in serum of animals. A dose dependent significant elevation (P<0.05) of total serum bilirubin level was observed which was optimized by using eight factorial, six axial and six central points as suggested by experimental design. Optimum levels of phenylhydrazine dose, total number of doses and a dose interval to achieve maximum elevation (4.06 mg/dl-1) of total serum bilirubin were found to be 11.56 mg/kg-1 body weight, 8 and 24.65 h, respectively. The induction procedure was validated by performing five replicate experiments on a group of five animals which showed 3.56 ± 0.47 mg/kg-1 body weight elevation in total serum bilirubin level.
Assuntos
Hemolíticos/efeitos adversos , Hiperbilirrubinemia/induzido quimicamente , Fenil-Hidrazinas/efeitos adversos , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Hiperbilirrubinemia/sangue , Masculino , Coelhos , Distribuição Aleatória , Ácido Ursodesoxicólico/efeitos adversosRESUMO
The effect of solvent polarity on extraction yield and antioxidant properties of phytochemical compounds in bean seeds was studied. Seed flour of three varieties of bean was extracted in a series of organic solvents with increasing polarity (n-hexane, petroleum ether, chloroform, ethyl acetate, ethanol, acetone and water). Preliminary screening of phytochemicals showed the presence of tannins, flavonoids, cardiac glycosides, anthocyanins, terpenoids, carotenoids, ascorbic acid and reducing compounds in all extracts. One way analysis of variance (ANOVA) of results showed that extraction yield, phytochemical content and antioxidant properties were significantly influenced (p<0.05) by the polarity of extracting solvents. The regression analysis of data showed polarity-dependent second order polynomial variations in the extraction yield, phytochemical contents, antioxidant activity, reducing properties and free radical scavenging activity of each variety. Extraction in highly polar solvents resulted in high extract yield but low phenolic and flavonoid content as compared to non-polar ones. The polarity-dependent increase in total antioxidant activity and reducing properties indicates the extraction of strong antioxidant compounds in polar solvents. The study suggests the use of a combination of polar and nonpolar solvents to increase the extraction efficiency of phytochemicals with good antioxidant quality from the bean and other legume seeds.
RESUMO
ABSTRACT Influence of high-dose gamma radiation and particle size on antioxidant properties of maize (Zea mays L.) flour was studied using response surface methodology. A central composite design based on three levels of each of particle size, in terms of mesh number (40, 60 and 80 meshes), and gamma radiation dose (25, 50 and 75 kGy) was constructed. A statistically significant dose-dependent decrease (p<0.05) in antioxidant properties of gamma irradiated flour was observed. However, an increase in the mesh number (decrease in particle size of flour) resulted in an increase in antioxidant properties. The optimum level of radiation dose to achieve maximum value of responses was found to be 50 kGy for Trolox equivalent total antioxidant activity (TETAOA), 25 kGy for iron chelating ability (ICA), 25 kGy for reducing power (RP) and 75 kGy for linoleic acid reduction capacity (LARC). However, the optimum level of mesh number to achieve desired levels of TETAOA, ICA, RP and LARC was found to be 80 meshes