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| Registros recuperados: 96 | |
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| Borghetti,Fabian; Lima,Elisa Coutinho de; Silva,Lucas de Carvalho Ramos. |
| Most studies conducted to test the allelopathic activity of plant parts have made use of water as solvent. However, the presence of polar, water-soluble substances, such as proteins and carbohydrates, tends to hamper the purification of active compounds. In this study, we present a simple purification procedure that separates the active fraction of the extract from the undesirable substances, thus facilitating the search for active molecules through standard chromatographic methods. Aqueous leaf extracts of three Cerrado species (Caryocar brasiliense, Qualea parviflora and Eugenia dysenterica) were prepared at 5% concentration (w/v) and stored at 4ºC (crude extracts). After 24 h, these solutions were filtered and freeze-dried. The powder obtained was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Cerrado; Freeze-drying; Leaf extract; Purification. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000100007 |
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| Moura,Raniere M.; Melo,Arthur A.; Carneiro,Rômulo F.; Rodrigues,Cícera R.f.; Delatorre,Plínio; Nascimento,Kyria S.; Saker-Sampaio,Silvana; Nagano,Celso S.; Cavada,Benildo S.; Sampaio,Alexandre H.. |
| Twenty species of marine invertebrates from the Brazilian coast were screened for hemagglutinating/hemolytic activity. In at least twelve tested species, hemagglutinating activity was different for different blood types, suggesting the presence of lectins. Extracts from four species showed hemolytic activity. Two new lectins were purified from the marine sponge Cliona varians (CvL-2) and sea cucumber Holothuria grisea (HGL). CvL-2 was able to agglutinate rabbit erythrocytes and was inhibited by galactosides. The hemagglutinating activity was optimal in pH neutral and temperatures below 70 °C. CvL-2 is a trimeric protein with subunits of 175 kDa. On the other hand, HGL showed both hemagglutinating and hemolytic activity in human and rabbit erythrocytes, but... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Purification; Hemolysis; Cytotoxicity; Galactose. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000200973 |
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| Sena,Amanda R.; Júnior,Gildomar L.V.; Góes Neto,Aristóteles; Taranto,Alex G.; Pirovani,Carlos P.; Cascardo,Júlio C.M.; Zingali,Russolina B.; Bezerra,Marcos A.; Assis,Sandra A.. |
| The enzyme glucanase from Moniliophthora perniciosa was produced in liquid medium and purified from the culture supernatant. A multivariate statistical approach (Response Surface Methodology - RSM) was employed to evaluate the effect of variables, including inducer (yeast extract) and fermentation time, on secreted glucanase activities M. perniciosa detected in the culture medium. The crude enzyme present in the supernatant was purified in two steps: precipitation with ammonium sulfate (70%) and gel filtration chromatography on Sephacryl S-200. The best inducer and fermentation time for glucanase activities were 5.9 g L-1 and 13 days, respectively. The results revealed three different isoforms (GLUI, GLUII and GLUIII) with purification factors of 4.33,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glucanase; Moniliophthora perniciosa; Production; Kinetic characterization; Purification; Heat stability. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000200019 |
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| OLIVEIRA,ANTÔNIA S. DE; LÓSSIO,CLÁUDIA F.; RANGEL,ANNE J.; MARTINS,MARIA G.Q.; NASCIMENTO,FERNANDO E.P. DO; ANDRADE,MARIA L.L. DE; CAVADA,BENILDO S.; LACERDA,SÍRLEIS R.; NASCIMENTO,KYRIA S. DO. |
| ABSTRACT Freshwater algae are rich sources of structurally biologically active metabolites, such as fatty acids, steroids, carotenoids and polysaccharides. Among these metabolites, lectins stand out. Lectins are proteins or glycoproteins of non-immune origin which bind to carbohydrates or glycoconjugates, without changing ligand structure. Many studies have reported on the use of Spirogyra spp. as effective bioindicators of heavy metals; however, reports on Spirogyra molecular bioprospecting are quite limited. Therefore, this study aimed to detect, isolate, purify and characterize a lectin present in the freshwater green algae Spirogyra. Presence of the lectin protein in the extract was detected by hemagglutination assays. Subsequently, the protein extract... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Algae; Characterization; Lectin; Purification. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000502113 |
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| Galante,Rafaela S.; Taranto,Alex G.; Koblitz,Maria G.B.; Góes-Neto,Aristóteles; Pirovani,Carlos P.; Cascardo,Júlio C.M.; Cruz,Sandra H.; Pereira,Gonçalo A.G.; Assis,Sandra A. de. |
| The enzyme chitinase from Moniliophthora perniciosa the causative agent of the witches' broom disease in Theobroma cacao, was partially purified with ammonium sulfate and filtration by Sephacryl S-200 using sodium phosphate as an extraction buffer. Response surface methodology (RSM) was used to determine the optimum pH and temperature conditions. Four different isoenzymes were obtained: ChitMp I, ChitMp II, ChitMp III and ChitMp IV. ChitMp I had an optimum temperature at 44-73ºC and an optimum pH at 7.0-8.4. ChitMp II had an optimum temperature at 45-73ºC and an optimum pH at 7.0-8.4. ChitMp III had an optimum temperature at 54-67ºC and an optimum pH at 7.3-8.8. ChitMp IV had an optimum temperature at 60ºC and an optimum pH at 7.0. For the computational... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chitinase; Moniliophthora perniciosa; Kinetic characterization; Purification; Isoenzymes; Heat stability; 3D structure; Comparative modeling. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000200016 |
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| Parreiras,P.M.; Lobato,F.C.F.; Heneine,C.F.L.G.D.; Assis,R.A.; Balsamão,G.M.; Nascimento,R.A.P.. |
| A prototoxina epsilon foi obtida a partir de cultivo líquido, rico em carboidratos, a partir de amostra de C. perfringens tipo D (INTA - Argentina), incubado em condições de anarobiose à 37ºC por oito horas. O sobrenadante da cultura foi concentrado utilizando-se o sistema Amicon com membrana de "cut off" de 10 kDa. O concentrado foi precipitado com sulfato de amônio (350 g/ml) e dissolvido em tampão fosfato 0,01 M (pH 7,2). A prototoxina purificada por cromatografia de troca iônica (DEAE-Sepharose CL 6B) e isolada no primeiro pico, mostrou uma banda única de aproximadamente 34kDa de peso molecular em SDS-PAGE, além de ser tóxica em camundongos. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Clostridium perfringens; Enterotoxemia; Purification; Epsilon toxin; Ion exchange chromatography. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352002000300019 |
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| Carvalho,A.V.A.; Heneine,L.G.D.; Assis,R.A.; Abreu,V.L.V.; Gonçalves,L.A.; Lobato,F.C.F.. |
| Empregaram-se os métodos cromatográficos de afinidade metálica e de imunoafinidade para purificação da toxina beta em sobrenadante de cultivo de Clostridium perfringens tipo C. Observaram-se, na eletroforese das primeiras frações eluidas nos dois métodos de purificação, uma banda de peso molecular aproximado de 38kDa, característica da forma monomérica de toxina beta de Clostridium perfringens tipo C, e bandas de peso moleculares superiores, referentes às suas formas oligoméricas. Maior rendimento foi obtido com a utilização do método de imunoafinidade. |
| Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Clostridium perfringens; Beta-toxin; Purification; Metal affinity; Immunoaffinity. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352006000200018 |
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| Slivinski,Christiane Trevisan; Machado,Alex Vinicius Lopes; Iulek,Jorge; Ayub,Ricardo Antônio; Almeida,Mareci Mendes de. |
| In this work, glucoamylase was produced by Aspergillus niger in solid-state fermentation. The enzyme was partially purified by ammonium sulphate precipitation and ion exchange and gel filtration chromatographies. Its molecular mass was estimated as 118.17 kDa by electrophoresis. The partially purified enzyme had an optimum pH range of 4.5-5.0 and an optimum temperature of 60 °C, with average activity 152.85 U mL-1. Thermal and pH stability assays with the crude extract showed that more than 60 % of the activity remained at pH 4.6 and 60 °C, even after an exposition to these conditions longer than 24 h. Yet, after purification, the enzyme was stable at these for at least 4 h, which indicated that its purification for use in starch saccharification was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glucoamylase; Aspergillus niger; Solid-state fermentation; Biochemical characterization; Purification. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000300018 |
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| Chaves,Daniel Gonçalves; Rodrigues,Cibele Velloso; Ferreira,Wanderley Almeida; Siqueira,Pollyana Fantini Miranda; Duarte,Clara Guerra; Carneiro-Proietti,Anna Bárbara de Freitas; Santoro,Marcelo Matos. |
| In this work, polyclonal antibodies anti-human Factor IX were produced in New Zealand rabbits by immunization with commercial pure human FIX (hFIX) (Octanyne®, Octapharma, USA). The serum containing immunoglobulins anti-hFIX was useful to detect hFIX antigen in human plasma fractions submitted to anionic exchange chromatographic process and with a large yield. Immunoassays (ELISA) using bovine serum albumin, trypsin and peptides generated by cleavage assays with trypsin as digestion enzyme was performed and revealed adequate specificity of the polyclonal antibodies produced. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Factor IX; Hemophilia B; HPLC; Purification; Antibodies; ELISA. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000500010 |
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| Neves,Valdir Augusto. |
| Soluble, ionically bound peroxidase (POD) and polyphenoloxidase (PPO) were extracted from the pulp of peach fruit during ripening at 20°C. Ionically bound form was purified 6.1-fold by DEAE-cellulose and Sephadex G-100 chromatography. The purified enzyme showed only one peak of activity on Sephadex G-100 and PAGE revealed that the enzyme was purified by the procedures adopted. The purified enzyme showed a molecular weight of 29000 Da, maximum activity at pH 5.0 and at 40ºC. The calculated apparent activation energy (Ea) for the reaction was10.04 kcal/mol. The enzyme was heat-labile in the temperature range of 60 to 75ºC with a fast inactivation at 75ºC. Measurement of residual activity showed a stabilizing effect of sucrose at various temperature/sugar... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Peach peroxidases; Ripening; Purification; Kinetics; Heat stability. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132002000100002 |
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| Benjamin,Sailas; Pandey,Ashok. |
| Three distinct forms (Lip A, Lip B and Lip C) of extra-cellular lipases (EC- 3.1.1.3), produced by Candida rugosa in solid state fermentation (SSF) were purified and characterised. SSF was carried out in glass columns using coconut oil cake and wheat bran. The enzyme was purified from the aqueous extract of fermented matter by ammonium sulphate precipitation, dialysis, ultra-filtration and gel filtration using Sephadex-200 to a 43-fold purification and 64.35-mg/ml specific activity. SDS-PAGE of purified enzyme revealed three distinct bands, indicating the existence of three iso-forms, Lip A, Lip B and Lip C with apparent molecular weight about 64,000, 62,000 and 60,000 Da, respectively. All the three iso-forms were optimally active at 35-40ºC and pH 7-8.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Candida rugosa; Lipases; Solid cultures; Purification; Characterization. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132000000500002 |
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| Santos,Alexandre Martins Costa; Oliveira,Jamil Silvano de; Bittar,Eustáquio Resende; Silva,Anderson Lourenço da; Guia,Marcos Luiz dos Mares; Bemquerer,Marcelo Porto; Santoro,Marcelo Matos. |
| The purpose of this work was to improve the separation and yield of pure β- and α-trypsin isoforms by ion-exchange chromatography and to characterize some physical-chemical properties of these isoforms. Purification of trypsin isoforms was performed by ion-exchange chromatography in 0.1 mol/L tris-HC buffer, pH 7.10 at 4ºC. The sample loading, salt concentration, flow rate and pH of mobile phase were varied to determine their effects on the resolution of the separation. The resolution was optimized mainly between β- and α-trypsin. Pure isoforms were obtained by chromatographying 100 mg of commercial trypsin during seven days, yielding 51 mg of high purity β-trypsin and 13 mg of α-trypsin partially pure, with small amounts of contaminating of ψ-trypsin.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Trypsin isoforms; Resolution; Ion-exchange chromatography; Purification; Specific activity; Mass spectrometry. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000400009 |
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| Registros recuperados: 96 | |
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