Made available in DSpace on 2014-12-17T14:10:28Z (GMT). No. of bitstreams: 1 DayaneLG_DISSERT.pdf: 2239805 bytes, checksum: 7c5ca3d63f1b06cc836a0c3ae876316c (MD5) Previous issue date: 2012-07-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Seaweeds are organisms known to exhibit a variety of biomolecules with pharmacological properties. The coast of Rio Grande do Norte has over 100 species of seaweeds, most of them not yet explored for their pharmacological potential. Sugars and phenolic compounds are the most studied of these being assigned a range of biological properties, such as anticoagulant , antiinflammatory, antitumor and antioxidant activities. In this work, we obtained methanolic extracts from thirteen seaweeds of the coast of Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; D. mertensis; Sargassum filipendula; Spatoglossum schr?ederi; Acanthophora specifera; Botryocladia occidentalis; Caulerpa cupresoides; C. racemosa; C. prolifera; C. sertularioides e Codium isthmocladum). They were evaluated as anticoagulant and antioxidant drugs, as well as antiproliferative drugs against the tumor cell line HeLa. None of the methanolic extracts showed anticoagulant activity, but when they were evaluated as antioxidant drugs all of extracts showed antioxidant activity in all tests performed (total antioxidant capacity, sequestration of superoxide and hydroxyl radicals, ferric chelation and reductase activity), especially the algae D. mentrualis, D. cilliolata and C. prolifera, who had the greatest potential to donate electrons.In addition, the ability of iron ions chelation appears as the main antioxidant mechanism of the methanolic extracts of these seaweeds mainly for the extract of the C. racemosa seaweed, which reached almost 100% activity. In the MTT assay, all extracts showed inhibitory activity at different levels againts HeLa cells. Moreover, D. cilliolata (MEDC) and D. menstrualis (MEDM) extracts showed specific activity to this cell line, not inhibiting the viability of 3T3 normal cell line, so they were chosen for detailing the antiproliferative mechanism of action. Using flow cytometry, fluorescence microscopy and in vitro assays we demonstrated that MEDC and MEDM induced apoptosis in HeLa cells by activation of caspases 3 and 9 and yet, MEDC induces cell cycle arrest in S phase. Together, these results showed that the methanolic extracts of brown seaweed D. menstrualis and D. cilliolata may contain agents with potential use in combatting cells from human uterine adenocarcinoma. This study also points to the need for more in-depth research on phytochemical and biological context to enable the purification of biologically active products of these extracts / Macroalgas marinhas s?o organismos conhecidos por apresentar uma diversidade de biomol?culas com propriedades farmacol?gicas. O litoral do Rio Grande do Norte apresenta mais de 100 esp?cies de macroalgas marinhas, a maioria delas ainda n?o explorada quanto ao seu potencial farmacol?gico. A??cares e compostos fen?licos s?o os compostos de macroalgas marinhas mais estudados, sendo atribu?da a estes uma gama de propriedades biol?gicas, como: atividade anticoagulante, antiinflamat?ria, antitumoral e antioxidante. Neste trabalho, foram obtidos extratos metan?licos de treze algas do litoral do Rio Grande do Norte (Dictyota cervicornis; Dictiopterys delicatula; Dictyota menstruallis; Dictyota mertensis; Sargassum filipendula; Spatoglossum schr?ederi; Acanthophora specifera;Botryocladia occidentalis;Caulerpa cupresoides; C. racemosa; C. prolifera; C. sertularioides e Codium isthmocladum), e esses foram avaliados quanto ao seu potencial anticoagulante, antioxidante e antiproliferativo. Nenhum dos extratos metan?licos apresentaram atividades anticoagulante, por?m quando avaliados com rela??o ao potencial antioxidante todos os extratos apresentaram atividade em quase todos os testes realizados (capacidade antioxidante total, sequestro de radicais super?xido e hidroxila, quela??o f?rrica e atividade redutora). Os extratos apresentaram resultados mais expressivos no teste de quela??o f?rrica, principalmente para o extrato da alga C. racemosa que chegou a quase 100% de atividade. Destaca-se tamb?m a capacidade de doar el?trons dos extratos, em especial, dasalgas D. mentrualis,D. cilliolata e C. prolifera que apresentaram os maiores potenciais. Nosestudos de citotoxidade, todos os extratos apresentaram atividades em diferentes n?veis frente as c?lulas tumorais HeLa, entretanto, os extratos de D. cilliolata (MEDC) e D. menstrualis (MEDM) apresentaram atividade espec?fica para esta linhagem celular, n?o apresentando citotoxidadepara as c?lulas3T3. Estudos com estes dois extratos utilizando t?cnicas de citometria de fluxo, microscopia de fluoresc?ncia e testes in vitro mostraram que MEDC e MEDM induzem a apoptose em c?lulas HeLa atrav?s da ativa??o das caspases 3 e 9 e ainda, MEDC induz a parada do ciclo celular na fase S. Juntos, esses resultados mostraram que os extratos metan?licos de algas marrom D. mentrualis e D. cilliolata podem conter agentes com potencial utiliza??o no combate de c?lulas de adenocarcinoma uterino humano. O presente estudo tamb?m aponta para a necessidade de investiga??es mais aprofundadas no ?mbito fitoqu?mico e biol?gico para se identificar produtos biologicamente ativos presentes nos extratos

Objetivo: Evaluar el efecto antibacteriano y citotóxico in vitro de los extractos metanólicos de Rubus idaeus (Frambuesa), Vaccinium myrtillus (Arándano azul) y Fragaria ananassa (Fresa) sobre cepas de Streptococcus mutans (ATCC®25175) y Streptococcus sanguinis (ATCC®10556).  Métodos: Se preparó un extracto metanólico por cada fruto. Se realizaron 10 repeticiones para cada grupo de extracto en cada caso. Se utilizó Clorhexidina al 2% como control positivo. Las propiedades antibacterianas de cada extracto se determinaron mediante el método de difusión en pozo. La concentración mínima inhibitoria (CMI) fue determinada mediante el método de microdilución y la citotoxicidad se analizó mediante la prueba de reducción de MTT, utilizando una línea celular MDCK.  Resultados: El extracto metanólico de arándano azul (Vaccinium myrtillus) tuvo el mayor efecto antibacteriano con un resultado de 30.44 ± 5.72 mm frente a Streptococcus mutans y de 29.33 ± 6.13 mm frente a Streptococcus sanguinis. Los extractos metanólicos de frambuesa, arándano azul y fresa obtuvieron una concentración mínima inhibitoria (CMI) frente a Streptococcus mutans de 0.8 µg/ml, 1.6 µg/ml y 3.1 µg/ml respectivamente; y los extractos metanólicos de arándano azul y fresa frente a Streptococcus sanguinis obtuvieron 3.1 µg/ml y 12.5 µg/ml respectivamente. Los ensayos de viabilidad celular demostraron una baja citotoxicidad de los extractos a altas concentraciones. La viabilidad celular fue más alta para los extractos de Arándano azul y Fresa con 98.2%.  Conclusiones: Los hallazgos evidencian las propiedades antibacterianas de los extractos metanólicos de Rubus idaeus (Frambuesa), Vaccinium myrtillus (Arándano azul) y Fragaria ananassa (Fresa) frente a los microorganismos previamente mencionados. No se evidenció citotoxicidad de los extractos a altas concentraciones. / Objective: Evaluate the in vitro antibacterial and cytotoxic effect of Rubus idaeus (Raspberry), Vaccinium myrtillus (Blueberry) and Fragaria ananassa (Strawberry) methanolic extracts against Streptococcus mutans (ATCC®25175) and Streptococcus sanguinis (ATCC®10556) strains. Methods: A methanolic extract was prepared for each fruit. Ten independent samples were made for each group of extract. 2% Chlorhexidine was used as a positive control. Antibacterial activity of each methanolic extract was determined by the well diffusion method. The minimum inhibitory concentration (MIC) was established by the microdilution method. Cytotoxicity was analyzed by the MTT reduction test, using a MDCK cell line. Results: The methanolic extract of blueberry (Vaccinium myrtillus) had the highest antibacterial effect with a result of 30.44 ± 5.72 mm against Streptococcus mutans and 29.33 ± 6.13 mm against Streptococcus sanguinis. The methanolic extracts of raspberry, blueberry and strawberry obtained a minimum inhibitory concentration (MIC) against Streptococcus mutans of 0.8 µg/ml, 1.6 µg/ml and 3.1 µg/ml respectively; and the methanolic extracts of blueberry and strawberry against Streptococcus sanguinis obtained 3.1 µg/ml and 12.5 µg/ml respectively. Cell viability assays demonstrated low cytotoxicity of the methanolic extracts at very high concentrations. Cell viability for blueberry and strawberry methanolic extracts was the highest with 98.2%. Conclusions: The findings evidence the antibacterial properties of methanolic extracts of Rubus idaeus (Raspberry), Vaccinium myrtillus (Blueberry) and Fragaria ananassa (Strawberry) against the previously mentioned microorganisms. The methanolic extracts didn’t show cytotoxicity at high concentrations. / Tesis