953 resultados para extraction method


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The reuse of industrial by-products such as red mud is of great importance. In the case of the building material industry the reuse of red mud requires a cautious attitude, since the enhanced radionuclide content of red mud can have an effect on human health. The natural radionuclide content of red mud from the Ajka red mud reservoir and the clay sample from a Hungarian brick factory were determined by gamma spectrometry. It was found that maximum 27.8% red mud content can be added to fulfil the conditions of the EU-BSS. The effect of heat treatment was investigated on a red mud-clay mixture and it was found that in the case of radon and thoron exhalation the applied heat reduced remarkably the exhalation capacities. The leaching features of red mud and different mixtures were studied according to the MSZ-21470-50 Hungarian standard, the British CEN/TS 14429 standard and the Tessier sequential extraction method. The Tessier method and the MSZ-21470-50 standard are suitable for the characterization of materials; however, they do not provide enough information for waste deposition purposes. To this end, we propose using the CEN/TS 14429 method, because it is easy to use, and gives detailed information about the material's behaviour under different pH conditions, however, further measurements are necessary.

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Residents of certain areas of Tanzania are exposed to mycotoxins through the consumption of contaminated maize based foods. In this study, 101 maize based porridge samples were collected from villages of Nyabula, Kikelelwa and Kigwa located in different agro-ecological zones of Tanzania. The samples were collected at three time points (time point 1, during maize harvest; time point 2, 6 months after harvest; time point 3, 12 months after harvest) over a 1-year period. Ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was used to detect and quantify 9 mycotoxins: aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), fumonisin B1 (FB1), fumonisin B2 (FB2), deoxynivalenol (DON), ochratoxin A (OTA) and zearaleneone (ZEN) in the samples following a QuEChERS extraction method. Eighty two percent of samples were co-contaminated with more than one group of mycotoxins. Fumonisins (FB1 + FB2) had the highest percentage occurrence in all 101 samples (100%) whereas OTA had the lowest (5%). For all three villages the mean concentration of FB1 was lowest in samples taken from time point 2. Conversely, In Kigwa village there was a distinct trend that AFB1 mean concentration was highest in samples taken from time point 2. DON concentration did not differ greatly between time points but the percentage occurrence varied between villages, most notably in Kigwa where 0% of samples tested positive. ZEN occurrence and mean concentration was highest in Kikelelwa. The results suggest that mycotoxin contamination in maize can vary based on season and agro-ecological zones. The high occurrence of multiple mycotoxins found in maize porridge, a common weaning food in Tanzania, presents a potential increase in the risk of exposure and significant health implications in children.

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This paper aims to verify the Burnout´s possibilities of incidence, finding the creating dimensions and comparing with the socio-demographics characteristics of the researched professionals. This quantitative-descriptive search has a population of 197 workers of 23 nourishing companies in Rio Grande do Norte. This population is predominantly male, younger than 28 years old, single, relatively instructed (57,07% with complete high school) and having just started their current job since 79% of the interviewees are in the company less than six years. The AUDITORIA DO SISTEMA HUMANO (ASH) model, utilized for investigation and developed for the Spaniards Quijano and Navarro in 1999, has several dimensions about human resources management and the organizational effectiveness, but only makes part of the research in 19 questions Burnout referring. It was used factorial analyses with extraction method, varimax rotation and Kaiser normalization with the intuition to define the creating dimensions of the syndrome, they were evaluated with Cronbach Alpha coefficient after extraction. The dimensions found through the factorial analyses were: emotional exhaustion, physical exhaustion and vitality. The accumulated explanation value reached 65,30% of total variation. The data socio-demographics don t justify the syndrome appearance, because the T test and ANOVA showed irrelevant values. It has been also observed that the founded dimensions were different of the Maslach sociopsychological perspective (emotional exhaustion, depersonalization and low professional realization) allowing comparison with others researches and the possibility to develop new ones with workers from different assistance areas. These new researches are important, since the syndrome refers to chronic labor stress consequences and any professional is favorable to Burnout, harmful to the company as to the collaborators

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With the need of the companies in becoming more competitive within the market, it arises an incessant search for selective human potential, with a high level of capacity and low rotativity, which motivation results in production raise, quality optimization and waste reduction. This scenario requires a strategy development which advantages the Human Resources Quality Management. This way, the model of the Human System Audit (HSA), developed by the Spanish researchers Ouijano and Navarro, presents itself as an important tool to diagnosis and evaluation, contemplating the environment where the organization is inserted, its strategies, its organizational design, its processes and its organizational effectiveness. In this sense, the present study has identified the existent relation between the professional satisfaction and the Organizational Culture, based in the model HSA. The research has been a quantitative-descriptive one and has had as population the technical-administrative workers from the Federal Center of Technical Education of Rio Grande do Norte (CEFET RN). The data collection has occurred during May, 2008, by means of the application of a questionnaire in the HSA model. The sample was composed by 167 subjects, distributed among the Five units of the institution. It was used the factorial analysis, with the extraction method of main components and orthogonal rotation varimax, in order to extract the dimensions of the satisfaction and of the organizational culture and the calculation of Cronbach s Alpha coefficient, to evaluate the reliability of these dimensions. The factorial analysis of the satisfaction indicators has identified four factors,, all of them showing significance: gratefulness and relationship , self-realization , stability and security and physical conditions and social benefits . The result of the factorial analysis with the indicators of the organizational culture has extracted four factors and among them, three of them have obtained significance: Personal Satisfaction Style , Competitive-Denial-Power Style and the Conventional-Dependent Style . After identifying the dimensions of the satisfaction and culture found at CEFET-RN, it has been notice the existence or not of relation among them, through the application of Pearson s coefficient. It has been verified that all of the dimensions of the Professional satisfaction are correlated with some dimension of the organizational culture, having in outstand position, with higher intensity, the relation between the culture style of Personal Satisfaction and the satisfaction factor referring to the self-realization

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Currently the organizations are passing for continuous cycles of changes due to necessity of survival in the work market. The administration of the future points a way to the organizations of today and tomorrow, the search of the competitiveness from loyalty and motivation of its staff. Of this form, the model of the Auditoria do Sistema Humano (ASH), developed for Spanish researchers and that now it is being applied in Brazil, contemplates a series of dimensions about Human Resources management quality in the companies and the organizational effectiveness, such as the environment where the company is inserted, the strategies, the organizational drawing, the psychological and psychosocial processes, e the reached results. In this direction, the present research analyzed the factors of job satisfaction and organizational commitment, making, also, a relation of causality between the same ones. The quantitative-descriptive research had as population the employees of twenty three nourishing industries of the State of Rio Grande do Norte (Brazil), registered in the Federacy of the Industries of the state. The collection of the data occurred for the months of October of 2005 and March of 2006, by means of the application of questionnaire of model ASH. The sample was composed for 197 employees, however it was observed presence of five outliers, that they had been excluded from the analysis of the data. To extract the dimensions of the satisfaction and the commitment and identification the factorial analysis was used, with extraction method of principal components, rotation Varimax and normalization Kaiser. The gotten dimensions had been evaluated with the calculation of the coefficient Alpha of Cronbach. The factorial analysis of the pointers of the organizational commitment and identification had extracted ten factors. Of these, four had gotten significance of the analyses inside: affective commitment, values commitment, continuance commitment and necessity commitment. The result of the analysis of the pointers of job satisfaction indicated four factors: extrinsic, motivations, relation with the friends and auto-accomplishment. To deal with the data the relation between job satisfaction and organizational commitment it was used technique of multiple regression. The correlation between commitment and satisfaction was satisfactory, detaching the affective commitment with bigger index of correlation, followed of the affective one

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Esta dissertação é composta por 5 artigos.

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A ocratoxina A é um composto formado a partir do metabolismo secundário de fungos dos gêneros Aspergillus e Penicillium. Uma vez que a presença dessa micotoxina nos alimentos causa sérios danos à saúde humana e animal, surge o interesse pelo desenvolvimento de métodos que visem a redução dos seus níveis em diferentes matrizes. Diversos processos de descontaminação têm sido propostos, sendo que os métodos de redução biológica tem recebido destaque. Esses métodos consistem na aplicação de micro-organismos ou de suas enzimas, o que gera a biotransformação ou degradação da toxina produzindo metabólitos com menor ou nenhuma toxicidade. Diante disso, o objetivo geral do trabalho foi avaliar o efeito da peroxidase na redução dos níveis de ocratoxina A. As enzimas peroxidases testadas foram a comercial e a obtida do farelo de arroz. Para a extração enzimática foram utilizadas as frações granulométricas do farelo de arroz de 48 a 100 mesh, sendo estas frações caracterizadas quimicamente. A peroxidase foi extraída do farelo de arroz em tampão 10 mM pH 5,0 e purificada por partição trifásica, obtendo 77,1% de recuperação e 9,2 para o fator de purificação. O método utilizado para a extração da ocratoxina A do sistema aquoso foi por partição líquido-líquido utilizando como solvente o clorofórmio, sendo esse método validado segundo os parâmetros de linearidade (0,1 a 20 ng mL-1), coeficientes de correlação (0,9997) e de determinação (0,9994), e limites de detecção (0,02) e quantificação (0,03). A afinidade entre as peroxidases e a ocratoxina A foi verificada segundo os parâmetros de KM e Vmáx, resultando em 0,00027 mM e 0,000015 mM min-1, respectivamente, para a peroxidase comercial, e 0,0065 mM e 0,000031 mM min-1 para a obtida do farelo de arroz. Com relação aos percentuais de redução de ocratoxina A, foram avaliadas 3 proporções enzima:substrato (1:10, 1:5 e 8:1 para a comercial e 1:10, 1:5 e a com atividade de 0,063 U mL-1 para a do farelo), sendo que as proporções que forneceram maior redução foi a de 8:1 para a enzima comercial (0,063 U mL-1) e a correspondente a 0,063 U mL-1 para a enzima obtida do farelo. Os percentuais de redução de ocratoxina A foram de 59% para a peroxidase comercial em 300 min e 41% para a peroxidase do farelo de arroz em 1440 min. O efeito de adsorção da ocratoxina A pela enzima peroxidase foi descartado uma vez que foi realizada a sua hidrólise com a enzima pepsina e verificado um percentual de 2,7% de adsorção, demonstrando que a redução foi por ação enzimática. A enzima obtida de farelo de arroz com atividade de 0,063 U mL-1 foi aplicada em suco de uva tinto e branco. Observou-se que para o primeiro não houve redução significativa, enquanto que para o segundo a redução foi de 17%. Neste trabalho, então, foi possível verificar a capacidade de redução dos níveis da ocratoxina A pela enzima peroxidase, tanto em sistema aquoso como no suco de uva integral branco.

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Orthopaedic infections can be polymicrobial existing as a microbiome. Infections often incorporate staphylococcal species, including Staphylococcus aureus. Such infections can lead to life threatening illness and implant failure. Furthermore, biofilm formation on the implant surface can occur, increasing pathogenicity, exacerbating antibiotic resistance and altering antimicrobial mechanism of action. Bacteria change dramatically during the transition to a biofilm growth state: phenotypically; transcriptionally; and metabolically, highlighting the need for research into molecular mechanisms involved in biofilm formation. Metabolomics can provide a tool to analyse metabolic changes which are directly related to the expressed phenotype. Here, we aimed to provide greater understanding of orthopaedic infection caused by S. aureus and biofilm formation on the implant surface. Through metagenome analysis by employing: implant material extraction; DNA extraction; microbial enrichment; and whole genome sequencing, we present a microbiome study of the infected prosthesis to resolve the causative species of orthopaedic hip infection. Results highlight the presence of S. aureus as a primary cause of orthopaedic infection along with Enterococcus faecium and the presence of secondary pathogen Clostridium difficile. Although results were hindered by the presence of host contaminating DNA even after microbial enrichment, conclusions could be made over the potential increased pathogenicity caused by the presence of a secondary pathogen and highlight method and sample preparation considerations when undertaking such a study. Following this finding, studies were focused on an orthopaedic clinical isolate of S. aureus and a metabolome extraction method for staphylococcal biofilms was developed using cell lysis through bead beating and solvent metabolome extraction. The method was found to be reproducible when coupled with liquid chromatography-mass spectrometry (LC-MS) and bioinformatics, allowing for the detection of significant changes in metabolism between planktonic and biofilm cultures to be identified and drug mechanism of actions (MOA) to be studied. Metabolomics results highlight significant changes in a number of metabolic pathways including arginine biosynthesis and purine metabolism between the two cell populations, evidence of S. aureus responding to their changing environment, including oxygen availability and a decrease in pH. Focused investigations on purine metabolism looking for biofilm modulation effects were carried out. Modulation of the S. aureus biofilm phenotype was observed through the addition of exogenous metabolites. Inosine increased biofilm biomass while formycin B, an inosine analogue, showed a dispersal effect and a potential synergistic effect in biofilm dispersal when coupled with gentamycin. Changes in metabolism between planktonic cells and biofilms highlight the requirement for antimicrobial testing to be carried out against planktonic cells and biofilms. Untargeted metabolomics was used to study the MOA of triclosan in S. aureus. The triclosan target and MOA in bacteria has already been characterised, however, questions remain over its effects in bacteria. Although the use of triclosan has come under increasing speculation, its full effects are still largely unknown. Results show that triclosan can induce a cascade of detrimental events in the cell metabolism including significant changes in amino acid metabolism, affecting planktonic cells and biofilms. Results and conclusions provide greater understanding of orthopaedic infections and specifically focus on the S. aureus biofilm, confirming S. aureus as a primary cause of orthopaedic infection and using metabolomic analysis to look at the changing state of metabolism between the different growth states. Metabolomics is a valuable tool for biofilm and drug MOA studies, helping understand orthopaedic infection and implant failure, providing crucial insight into the biochemistry of bacteria for the potential for inferences to be gained, such as the MOA of antimicrobials and the identification of novel metabolic drug targets.

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Neste trabalho é proposto pela primeira vez, o desenvolvimento e validação de um método analítico baseado no emprego da dispersão da matriz em fase sólida (MSPD) modificada, para extração das espécies CH3Hg+ e Hg2+ em amostras de peixe e determinação por cromatografia em fase gasosa acoplada à espectrometria de massas (GC-MS). O método de extração utilizando a MSPD combina o rompimento da estrutura física da amostra, através da maceração e do uso de SiO2 como suporte sólido, com o método da extração ácida, utilizando uma solução de HCl 4,2 mol L-1 e NaCl 0,5 mol L-1. Para otimização da MSPD, foram avaliados parâmetros como massa de amostra, massa de suporte sólido, concentração de HCl, concentração de NaCl, tipo de suporte sólido e o tempo de agitação, com auxílio da metodologia de superfície de resposta. Além disso, a etapa de derivatização e a separação cromatográfica também foram otimizadas na determinação de CH3Hg+ e Hg2+ por GC-MS. O método mostrouse adequado para extração e determinação de espécies de mercúrio através da aplicação em materiais de referência certificados de fígado de peixe (DOLT-3) e músculo de peixe (DORM-2), apresentando boas concordâncias com os valores certificados e desvio padrão relativo inferior a 9,5%. Os limites de detecção foram de 0,06 e 0,12 µg g-1 para CH3Hg+ e Hg2+, respectivamente. Além disso, foi observado um significativo efeito de matriz e, por isso, a calibração foi feita com curvas preparadas com o extrato da MSPD. O método mostrou boa concordância na comparação entre a soma da concentração das espécies e a concentração de mercúrio total determinada por espectrometria de massas com plasma indutivamente acoplado com geração de vapor frio (CVG-ICP-MS), após digestão assistida por micro-ondas (MAD) em peixes do tipo atum (Thunnus thynnus), cação anjo (Squatina squatina) e cação viola (Rhinobatos blochii.).

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This paper aims to verify the Burnout´s possibilities of incidence, finding the creating dimensions and comparing with the socio-demographics characteristics of the researched professionals. This quantitative-descriptive search has a population of 197 workers of 23 nourishing companies in Rio Grande do Norte. This population is predominantly male, younger than 28 years old, single, relatively instructed (57,07% with complete high school) and having just started their current job since 79% of the interviewees are in the company less than six years. The AUDITORIA DO SISTEMA HUMANO (ASH) model, utilized for investigation and developed for the Spaniards Quijano and Navarro in 1999, has several dimensions about human resources management and the organizational effectiveness, but only makes part of the research in 19 questions Burnout referring. It was used factorial analyses with extraction method, varimax rotation and Kaiser normalization with the intuition to define the creating dimensions of the syndrome, they were evaluated with Cronbach Alpha coefficient after extraction. The dimensions found through the factorial analyses were: emotional exhaustion, physical exhaustion and vitality. The accumulated explanation value reached 65,30% of total variation. The data socio-demographics don t justify the syndrome appearance, because the T test and ANOVA showed irrelevant values. It has been also observed that the founded dimensions were different of the Maslach sociopsychological perspective (emotional exhaustion, depersonalization and low professional realization) allowing comparison with others researches and the possibility to develop new ones with workers from different assistance areas. These new researches are important, since the syndrome refers to chronic labor stress consequences and any professional is favorable to Burnout, harmful to the company as to the collaborators

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With the need of the companies in becoming more competitive within the market, it arises an incessant search for selective human potential, with a high level of capacity and low rotativity, which motivation results in production raise, quality optimization and waste reduction. This scenario requires a strategy development which advantages the Human Resources Quality Management. This way, the model of the Human System Audit (HSA), developed by the Spanish researchers Ouijano and Navarro, presents itself as an important tool to diagnosis and evaluation, contemplating the environment where the organization is inserted, its strategies, its organizational design, its processes and its organizational effectiveness. In this sense, the present study has identified the existent relation between the professional satisfaction and the Organizational Culture, based in the model HSA. The research has been a quantitative-descriptive one and has had as population the technical-administrative workers from the Federal Center of Technical Education of Rio Grande do Norte (CEFET RN). The data collection has occurred during May, 2008, by means of the application of a questionnaire in the HSA model. The sample was composed by 167 subjects, distributed among the Five units of the institution. It was used the factorial analysis, with the extraction method of main components and orthogonal rotation varimax, in order to extract the dimensions of the satisfaction and of the organizational culture and the calculation of Cronbach s Alpha coefficient, to evaluate the reliability of these dimensions. The factorial analysis of the satisfaction indicators has identified four factors,, all of them showing significance: gratefulness and relationship , self-realization , stability and security and physical conditions and social benefits . The result of the factorial analysis with the indicators of the organizational culture has extracted four factors and among them, three of them have obtained significance: Personal Satisfaction Style , Competitive-Denial-Power Style and the Conventional-Dependent Style . After identifying the dimensions of the satisfaction and culture found at CEFET-RN, it has been notice the existence or not of relation among them, through the application of Pearson s coefficient. It has been verified that all of the dimensions of the Professional satisfaction are correlated with some dimension of the organizational culture, having in outstand position, with higher intensity, the relation between the culture style of Personal Satisfaction and the satisfaction factor referring to the self-realization

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This report presents a new extraction method of the dinophysistoxins (DTXs), confirmed by quantification using high-performance liquid chromatography coupled to mass spectrometry with an ion trap and electro spray interface (HPLC/ESI/MS2). The method originality consists on the adaptation of DTXs basic extraction procedure (liquid/ liquid) to a solid phase extraction (SPE) via a robotic station: ASPEC XLi The parameters of the automatization procedure were optimized to obtain the best DTXs recovery rate. These improvements were loaded with digestive gland mussel homogenat realized on a silica cartridge SPE, activated in hexane/chloroform (50:50), washed with hexane/chloroform (50:50) and extracted by an elution gradient (chloroform methanol (65:35) and methanol (100%)). This method was validated according to two normative referentials (linearity, detection quantification limits and accuracy…) : - The Guide of the Pharmacy industry: Analytical Validation, report of the commission SFSTP 1992 (French Corporation of the Sciences and Technical Pharmaceutical), - - The Procedure of validation of an alternative method in compare to a reference method. (AFNOR, 1998. NF V 03-110). Comparison with the classical liquid/liquid extraction and the automated method present clear advantages. In an analytical method the extraction is generally considered to be the most labor-intensive and error-prone step. This new procedure allowed us to increase throughput, to improve the reproducibility and to reduce the error risks due to the individual manual treatments.

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Currently the organizations are passing for continuous cycles of changes due to necessity of survival in the work market. The administration of the future points a way to the organizations of today and tomorrow, the search of the competitiveness from loyalty and motivation of its staff. Of this form, the model of the Auditoria do Sistema Humano (ASH), developed for Spanish researchers and that now it is being applied in Brazil, contemplates a series of dimensions about Human Resources management quality in the companies and the organizational effectiveness, such as the environment where the company is inserted, the strategies, the organizational drawing, the psychological and psychosocial processes, e the reached results. In this direction, the present research analyzed the factors of job satisfaction and organizational commitment, making, also, a relation of causality between the same ones. The quantitative-descriptive research had as population the employees of twenty three nourishing industries of the State of Rio Grande do Norte (Brazil), registered in the Federacy of the Industries of the state. The collection of the data occurred for the months of October of 2005 and March of 2006, by means of the application of questionnaire of model ASH. The sample was composed for 197 employees, however it was observed presence of five outliers, that they had been excluded from the analysis of the data. To extract the dimensions of the satisfaction and the commitment and identification the factorial analysis was used, with extraction method of principal components, rotation Varimax and normalization Kaiser. The gotten dimensions had been evaluated with the calculation of the coefficient Alpha of Cronbach. The factorial analysis of the pointers of the organizational commitment and identification had extracted ten factors. Of these, four had gotten significance of the analyses inside: affective commitment, values commitment, continuance commitment and necessity commitment. The result of the analysis of the pointers of job satisfaction indicated four factors: extrinsic, motivations, relation with the friends and auto-accomplishment. To deal with the data the relation between job satisfaction and organizational commitment it was used technique of multiple regression. The correlation between commitment and satisfaction was satisfactory, detaching the affective commitment with bigger index of correlation, followed of the affective one

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Purpose: To evaluate the cytotoxic, anti-inflammatory and antioxidant activities of four different solvent extracts obtained from the aerial parts of Galega officinalis L Methods: The hexane, DCM, methanol and water extracts of G. officinalis were successively obtained by soxhlet extraction method. The cytotoxic activity of the extracts was assessed against human lung carcinoma (A-549), human colorectal adenocarcinoma (HT-29), human brain glioblastoma (U-87), and colon adenocarcinoma (DLD-1) by Resazurine test. The antioxidant activity of extracts were determined by Folin-Ciocalteau, oxygen radical absorbing capacity (ORAC), and 2’.7’-dichlorofluorescin-diacetate (DCFH-DA) cell-based assay while their anti-inflammatory activity was determined by nitric oxide (NO) assay. Results: DCM extract showed strong cytotoxic activity against lung adenocarcinoma and brain glioblastoma cell lines, with IC50 (concentration inhibiting 50 % of cell growth) values of 11 ± 0.4 and 16 ± 3 μg/mL, respectively. The hexane extract showed moderate anticancer activity against the same cell lines (59 ± 13 and 63 ± 16 μg/mL, respectively). DCM extract also showed significant anti-inflammatory activity, inhibiting NO release by 86.7 % at 40 μg/mL in lipopolysaccharide (LPS) - stimulated murine RAW 264.7 macrophages. Of all test extracts, the methanol extract of G. officinalis showed the highest antioxidant activity with 2.33 ± 0.09 μmol Trolox/mg , 7.10 ± 0.9 g tannic acid equivalent (TAE), and IC50 of 44 ± 4 μg/mL. Conclusion: The findings of this study suggest that DCM extract may possess anticancer effect against lung adenocarcinoma and brain glioblastoma, as well as serve as an anti-inflammatory agent.

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Dengue, amongst the virus illnesses one can get by vectorial transmission, is the one that causes more impact in the morbidity and mortality of world s population. The resistance to the insecticides has caused difficulties to control of vector insect (Aedes aegypti) and has stimulated a search for vegetables with larvicidal activity. The biodiversity of Caatinga is barely known and it is potential of use even less. Some plants of this biome are commercialized in free fairs northeast of Brazil, because of its phytotherapics properties. The vegetables in this study had been selected by means of a questionnaire applied between grass salesmen and natives of the Serido region from Rio Grande do Norte state; culicids eggs had been acquired with traps and placed in container with water for the larva birth. Thirty larvae had been used in each group (a group control and five experimental groups), with four repetitions four times. The vegetables had been submitted to the processes of decoction, infusion and maceration in the standard concentration of 100g of the vegetable of study in 1l of H2O and analyzed after ½, 1, 2, 4, 8, 12, 24 and 48 hours for verification of the average lethal dose (LD50) from the groups with thirty larva. The LD50 was analyzed in different concentrations (50g/l, 100g/l, 150g/l, 200g/l e 300g/l) of Aspidosperma pyrifolium Mart. 48 extracts of rind, leaf and stem of the seven vegetal species: Aspidosperma pyrifolium Mart., Mimosa verrucosa Benth, Mimosa hostilis (Mart.) Benth., Myracrodruon urundeuva Allemão, Ximenia americana L, Bumelia sartorum Mart Zizyphus joazeiro Mart, had been analyzed. The extracts proceeding from the three methods were submitted to the freezedrying, to evaluate and to quantify substances extracted in each process. The results had shown that Aspidosperma pyrifolium Mart. and Myracrodruon urundeuva Allemão are the species that are more distinguished as larvicidal after 24 hours of experiment, in all used processes of extraction in the assays. The Zizyphus joazeiro Mart species has not shown larvicidal activity in none of the assays. In relation to the extraction method, the decoction was the most efficient method in the mortality tax of the A. aegypti larvae