76 research outputs found

    Cost-effective fibrinolytic enzyme production by microalga Dunaliella tertiolecta using medium supplemented with corn steep liquor

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    Abstract A fibrinolytic enzyme from the microalga Dunaliella tertiolecta was produced under mixotrophic conditions using different corn steep liquor (CSL) concentrations ( 0 ≀ CLS ≀ 0.75%), purified using a combination of salting out and ion-exchange chromatography, and then biochemical characterized. Cultivation of this microalga using 0.5% CSL led to the highest maximum cell concentration (1.960±0.010 mg L-1) and cell productivity (0.140g L-1 day-1), besides a high fibrinolytic activity of the extract obtained by the homogenization method (102 ±1 U mL-1). The enzyme extracted from the microalgal biomass was 5-fold purified with a 20% yield and was found to have a specific activity of 670 U mg-1. The enzyme, whose molecular weight determined by fibrin zymography was 10 kDa, was shown to be stable at pH 3.0–9.0 and up to 70°C with optimal pH and temperature values of 8.0 and 50°C, respectively. When compared to other fibrinolytic enzymes, this protease stood out for its high fibrinolytic activity, which was enhanced by Fe2+, inhibited by Zn2+, Cu2+, Mg2+, and Ca2+, and strongly inhibited by phenylmethylsulfonyl fluoride, suggesting that it belongs to the serine metalloprotease family. Moreover, thanks to its thermal stability, the enzyme may be easily preserved and activated under high-temperature conditions

    Fibrinolytic protease production by new Streptomyces sp. DPUA 1576 from Amazon lichens

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    Background: Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 22 factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results: The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm2 was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied conditions. Conclusions: These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production

    Fibrinolytic protease production by new Streptomyces sp. DPUA 1576 from amazon lichens

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    Background Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 22 factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm2 was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied conditions. Conclusions These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production.The authors thank CAPES (National Council for the Improvement of Higher Education) for the scholarship and CNPq/RENORBIO (National Counsel of Technological and Scientific Development, N. 55146/2010-3) and FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco, 0158-2.12/11) for the financial support

    Purification of a lectin from Cratylia mollis crude extract seed by a single step PEG/phosphate aqueous two-phase system

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    The partitioning and purification of lectins from the crude extract of Cratylia mollis seeds (Cramoll 1,4) was investigated in aqueous two-phase systems (ATPS). A factorial design model (24) was used to evaluate the influence of polyethylene glycol (PEG) molar mass (15008000g/mol), PEG concentration (12.517.5% w/w), phosphate (1015% w/w) concentration, and pH (68) on the differential partitioning, purification factor, and yield of the lectin. Polymer and salt concentration were the most important variables affecting partition of lectin and used to find optimum purification factor by experimental BoxBehnken design together with the response surface methodology (RSM). ATPS showed best conditions composed by 13.9% PEG1500, 15.3% phosphate buffer at pH 6, which ensured purification factor of 4.70. Sodium dodecyl sulfatepolyacrylamide gel electrophoresis showed a single band of protein with 26.1kDa. Furthermore, results demonstrated a thermostable lectin presenting activity until 60°C and lost hemagglutinating activity at 80°C. According to the obtained data it can be inferred that the ATPS optimization using RSM approach can be applied for recovery and purification of lectins.We are grateful to the following bodies for the grants awarded: CAPES (Coordination for the Improvement of Level Personnel Superior); FACEPE (Pernambuco Science and Technology Foundation): Researcher's scholarship grant: BFP-0017-5.05/18 CNPq (National Council for Scientific Development and Technological) process: 427153/2016-6 and we also thank the reviewers for their valuable comments and suggestions as these helped us to improve the manuscript.info:eu-repo/semantics/publishedVersio

    AIDS and jail: social representations of women in freedom deprivation situations

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    Abstract OBJECTIVE To graspthe AIDS social representations built by freedom-deprived women. METHOD Descriptive study with a quali-quantitative approach that involved 174 convicted women in a women's prison in a capital city of the Brazilian northeastern region. Aword-association test was applied in October and November 2014, using AIDS as a stimulus. The corpuswas processed usingIramuteq software. Descending Hierarchical Classification and Correspondence Factor Analysis were applied. RESULTS The content that comprises the social representation of AIDS was influenced by the prison context, which was pervaded by a lack of assistance, lack of knowledge, discrimination, and suffering that disclosed vulnerability to HIV/AIDS factors such as unprotected sex and object sharing. This underlines the stigma and fear of the illness, in addition to favoring and supporting negative feelings and a sense of rejection. CONCLUSION To consider the use of this representational amalgam to ensure a comprehensive, contextualized care can help redirect practices, motivate self-care practices, and reduce prejudiced attitudes

    Screening, production and biochemical characterization of a new fibrinolytic enzyme produced by Streptomyces sp. (Streptomycetaceae) isolated from Amazonian lichens

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    Thrombosis is a pathophysiological disorder caused by accumulation of fibrin in the blood. Fibrinolytic proteases with potent thrombolytic activity have been produced by diverse microbial sources. Considering the microbial biodiversity of the Amazon region, this study aimed at the screening, production and biochemical characterization of a fibrinolytic enzyme produced by Streptomyces sp. isolated from Amazonian lichens. The strain Streptomyces DPUA1576 showed the highest fibrinolytic activity, which was 283 mm2. Three variables at two levels were used to assess their effects on the fibrinolytic production. The parameters studied were agitation (0.28 - 1.12 g), temperature (28 - 36 ÂșC) and pH (6.0 - 8.0); all of them had significant effects on the fibrinolytic production. The maximum fibrinolytic activity (304 mm2) was observed at 1.12 g, 28 ÂșC, and pH of 8.0. The crude extract of the fermentation broth was used to assess the biochemical properties of the enzyme. Protease and fibrinolytic activities were stable during 6 h, at a pH ranging from 6.8 to 8.4 and 5.8 to 9.2, respectively. Optimum temperature for protease activity ranged between 35 and 55 °C, while the highest fibrinolytic activity was observed at 45 ÂșC. Proteolytic activity was inhibited by Cu2+ and Co2+ ions, phenylmethylsulfonyl fluoride (PMSF) and pepstatin A, which suggests that the enzyme is a serine protease. Enzymatic extract cleaved fibrinogen at the subunits A-chain, A-chain, and -chain. The results indicated that Streptomyces sp. DPUA 1576 produces enzymes with fibrinolytic and fibrinogenolytic activity, enzymes with an important application in the pharmaceutical industry.The authors grateful acknowledge the financial support of Fundação de Amparo a Pesquisa do Estado de Pernambuco (FACEPE, Pernambuco, Brazil, N. 0158-2.12/11), CNPq/ RENORBIO (National Counsel of Technological and Scientific Development, N.55146/2010-3) and National Council for the Improvement of Higher Education (CAPES, Brazil) for the scholarship. The author thanks editor and reviewers for their review and comments.info:eu-repo/semantics/publishedVersio
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