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1.
Braz. j. biol ; 82: e234500, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153464

RESUMO

Abstract This work aimed to obtain aspartic proteases of industrial and biotechnological interest from the stomach of the crevalle jack fish (Caranx hippos). In order to do so, a crude extract (CE) of the stomach was obtained and subjected to a partial purification by salting-out, which resulted in the enzyme extract (EE) obtainment. EE proteases were characterized physicochemically and by means of zymogram. In addition, the effect of chemical agents on their activity was also assessed. By means of salting-out it was possible to obtain a purification of 1.6 times with a yield of 49.4%. Two acid proteases present in the EE were observed in zymogram. The optimum temperature and thermal stability for EE acidic proteases were 55 ºC and 45 °C, respectively. The optimum pH and pH stability found for these enzymes were pH 1.5 and 7.0, respectively. Total inhibition of EE acid proteolytic activity was observed in the presence of pepstatin A. dithiothreitol (DTT) and Ca2+ did not promote a significant effect on enzyme activity. In the presence of heavy metals, such as Al3+, Cd2+ and Hg2+, EE acidic proteases showed more than 70% of their enzymatic activity. The results show that it is possible to obtain, from the stomach of C. hippos, aspartic proteases with high proteolytic activity and characteristics that demonstrate potential for industrial and biotechnological applications.


Resumo Este trabalho objetivou obter proteases aspárticas de interesse industrial e biotecnológico a partir do estômago do peixe xaréu (Caranx hippos). Para isso, foi obtido um extrato bruto do estômago, o qual foi submetido a uma purificação parcial por salting-out onde se obteve o extrato enzimático (EE). As proteases do EE foram caracterizadas físico-quimicamente e através de zimograma. Além disso, o efeito de agentes químicos sobre sua atividade também foi avaliado. Através de salting-out foi possível obter uma purificação de 1,6 vezes com rendimento de 49,4%. Foram observadas duas proteases ácidas presentes no EE através de zimograma. A temperatura ótima e a estabilidade térmica para as proteases ácidas do EE foram de 55 ºC e 45 °C, respectivamente. O pH ótimo e a estabilidade ao pH encontrados para estas enzimas foram o pH 1,5 e 7,0, respectivamente. Observou-se a inibição total da atividade proteolítica ácida do EE na presença de pepstatina A. O ditiotreitol (DTT) e o Ca2+ não promoveram efeito significativo na atividade enzimática. Na presença de metais pesados, como Al3+, Cd2+ e Hg2+, o EE manteve mais de 70% de atividade enzimática do EE. Os resultados mostram que é possível obter, a partir do estômago de C. hippos, proteases aspárticas com alta atividade proteolítica e características que demonstram potencial para aplicações industriais e biotecnológicas.

2.
Braz J Biol ; 82: e234500, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787732

RESUMO

This work aimed to obtain aspartic proteases of industrial and biotechnological interest from the stomach of the crevalle jack fish (Caranx hippos). In order to do so, a crude extract (CE) of the stomach was obtained and subjected to a partial purification by salting-out, which resulted in the enzyme extract (EE) obtainment. EE proteases were characterized physicochemically and by means of zymogram. In addition, the effect of chemical agents on their activity was also assessed. By means of salting-out it was possible to obtain a purification of 1.6 times with a yield of 49.4%. Two acid proteases present in the EE were observed in zymogram. The optimum temperature and thermal stability for EE acidic proteases were 55 ºC and 45 °C, respectively. The optimum pH and pH stability found for these enzymes were pH 1.5 and 7.0, respectively. Total inhibition of EE acid proteolytic activity was observed in the presence of pepstatin A. dithiothreitol (DTT) and Ca2+ did not promote a significant effect on enzyme activity. In the presence of heavy metals, such as Al3+, Cd2+ and Hg2+, EE acidic proteases showed more than 70% of their enzymatic activity. The results show that it is possible to obtain, from the stomach of C. hippos, aspartic proteases with high proteolytic activity and characteristics that demonstrate potential for industrial and biotechnological applications.


Assuntos
Peptídeo Hidrolases , Animais , Concentração de Íons de Hidrogênio , Temperatura
3.
Sci Total Environ ; 595: 633-641, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28411562

RESUMO

The oil well blowout releases hydrocarbons into the marine environment as an oil droplets and gas bubbles dispersion. The oil trajectory is strongly influenced by physical, chemical and biological processes. In general, the ocean oil drift studies are based on a two-dimensional approach, whereas the whole oil from a well blowout can be represented by a surface oil leak in the same geographical coordinates. This work is a case study, where MOHID software is used at the Campos Basin region, in which the Lagrangian results of the surface oil leaks were confronted to their well blowout scenarios in different conditions of depth, seasonality (summer and winter), and use of dispersants at the source of the leak. The research results reinforced the importance of the three-dimensional approach to the scenario of deep and ultra-deep waters, especially for cases in which the dispersant injection into the source of the leak was considered.

4.
Artigo em Inglês | MEDLINE | ID: mdl-23856041

RESUMO

In this work we study two types of wood fossils (Gymnosperms, Araucariaceae) from the Crato Formation of Araripe Basin in Brazil, from the Cretaceous Period. The samples were characterized by Raman and infrared spectroscopies, X-ray diffraction and scanning electron microscopy. The results obtained by different techniques showed that although the rocks surrounding the fossils have predominantly the same constitution - calcite - however, the formation processes of these types of wood fossils are quite different. One of the fossils, denominated as light wood, is predominantly composed of gypsum, while the other fossil, the dark wood, is rich in amorphous carbon, possibly the kerogen type. Implications relative to the environment where the plants lived millions years ago are also given. Finally, the results highlight the constitution of one of the most important paleontological sites of the Cretaceous Period in the South America.


Assuntos
Fósseis , Fenômenos Geológicos , Madeira/química , Brasil , Imagem Óptica , Espectrofotometria Infravermelho , Análise Espectral Raman , Fatores de Tempo , Madeira/ultraestrutura , Difração de Raios X
5.
Tissue Cell ; 41(1): 43-50, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18801546

RESUMO

Bacterial dental plaque is considered to be the main cause of periodontal diseases, but progression of the disease is also related to the host inflammatory response. The earliest affected tissue is the gingiva, but the specific mechanisms involved in the onset of this condition remain unclear. Frequently, collagen degradation is pointed as the main marker of periodontal disease progression, but the organization of the fibers in the gingival tissue is still unknown. The aim of the present study was to investigate the gingival extracellular matrix in a model of ligature-induced periodontal disease. Analysis of the microbiota indicated a progressive increase in the ratio of Gram-negative/Gram-positive microorganisms. There was no difference in the organization of reticulin fibers next to the epithelial basement membrane, whereas the arrangement of collagen fibers in the gingival connective tissue was significantly affected. Animals with inflammation presented a reduction of 35% in the total area occupied by collagen fibers. However, these fibers were thicker and more densely packed. These alterations involve type I, type III and type VI collagens as determined by immunohistochemistry. The results demonstrated the occurrence of marked reorganization of the gingival extracellular matrix in response to the inflammatory process, indicating a new paradigm in the periodontal disease progression: collagen degradation and fibers thickening, simultaneously.


Assuntos
Colágeno/metabolismo , Gengiva/metabolismo , Gengiva/patologia , Doenças Periodontais/metabolismo , Doenças Periodontais/patologia , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Colágeno Tipo VI/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
6.
Tissue Cell ; 40(4): 283-92, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18439638

RESUMO

Periodontal disease constitutes the most frequent chronic diseases in human dentition. Bacterial plaque is the main etiologic agent, although it is the host immune response that causes periodontal tissue destruction. Diabetes is considered an important risk factor, not only for the onset but also for progression of the disease. The aim of this study was to analyze structural changes in the rat gingival epithelium and connective tissue in response to the experimental periodontal disease induced by the ligature technique, under the influence of diabetes. The results showed that experimental periodontal disease is characterized by marked inflammation, affecting both the epithelial and connective tissues, causing degeneration of the dermal papilla, increase in the number of inflammatory cells, destruction of reticulin fibers, and accumulation of dense collagen fibers (fibrosis). These changes were worsened by diabetes, apparently by hampering the inflammatory response and affecting tissue repair of the affected tissues.


Assuntos
Tecido Conjuntivo/patologia , Diabetes Mellitus Tipo 1/complicações , Epitélio/patologia , Gengiva/patologia , Doenças Periodontais/complicações , Animais , Peso Corporal , Movimento Celular , Colágeno/metabolismo , Diabetes Mellitus Tipo 1/induzido quimicamente , Matriz Extracelular/metabolismo , Inflamação , Cinética , Masculino , Ratos , Ratos Wistar , Solubilidade , Estreptozocina
7.
J Periodontal Res ; 43(1): 48-54, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18230106

RESUMO

BACKGROUND AND OBJECTIVE: Periodontal disease corresponds to a group of lesions that affect the tooth-supporting tissues present in the dental follicle. Although bacterial plaque is important, the immune response also contributes to the destruction of periodontal tissues. Diabetes mellitus is closely associated with the development, progression and severity of periodontal disease because it not only affects extracellular matrix organization but also the tissue response to inflammation. The objective of the present investigation was to study the influence of diabetes on experimental periodontal disease by evaluating the degradation of extracellular matrix through the analysis of matrix metalloproteinase (MMP)-2 and MMP-9 expression and activity, using immunofluorescence, zymography and real-time reverse transcription-polymerase chain reaction. MATERIAL AND METHODS: Wistar rats were divided into normal and diabetic groups and evaluated 0, 15 and 30 d after the induction of periodontal disease by ligature. RESULTS: MMP-2 and -9 were detected in epithelial cells, in the blood vessel endothelium and in connective tissue cells. The same profile of enzymatic expression of MMP-2 and -9 was observed in normal and diabetic animals, with a peak in activity at day 15 of inflammation. However, in diabetic animals, MMP-2 gelatinolytic activity was reduced after the inflammatory stimulus, whereas that of MMP-9 was increased. MMP-2 gene expression decreased with inflammation in both normal groups and groups with diabetes. In contrast, MMP-9 expression increased in normal animals and decreased in diabetic animals after inflammation. CONCLUSION: The results suggest the involvement of MMP-2 and -9 in the dynamics of periodontal disease and that variation in their expression levels results in differences in tissue organization and wound healing in normal and diabetic animals.


Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Doenças Periodontais/enzimologia , Animais , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Tipo 1/complicações , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , RNA/análise , Ratos , Ratos Wistar , Fatores de Tempo
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