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Análise da microbiota associada à ascídia Didemnum granulatum para a produção de metabólitos secundários bioativos
(Universidade Federal de São Carlos, 2010-06-01) Carvalho, Erica de; Seleghim, Mirna Helena Regali; https://lattes.cnpq.br/5998337634888263; https://lattes.cnpq.br/9727019290567400
Studies of marine natural products in 20 years of research have revealed a wide variety of molecules with complex structures and hitherto unknown, and potent biological activities. The aims of this study were to isolate microbial strains associated with Didemnum granulatum, to fermentate such strains for the production of crude extracts and the screening of these extracts for bioactive secondary metabolites. For the isolation of the strains, six different culture media were prepared with artificial sea water: malt extract 2% and 3%, carrot/potato, corn, oat and GPY. The strains were cultivated for 30 days in 250mL of the same culture media. The crude extracts were obtained by partition with ethyl acetate. The extracts were sent for the cytotoxic activity bioassay and analyzed by thin layer chromatography (TLC) on silica gel plate (with absorption in UV-vis). Among the 26 extracts, samples DG (M3) 6'C and DG (M3) 5'C showed potent cytotoxic activity, samples DG (B) 13, DG (M3) 1 and DG (G) 2B a moderate activity. The analysis by TLC indicated the presence of bioactive secondary metabolites in the extracts. The strains were identified as bioactive three fungal: DG (M 3) 6'C (Penicillium sp.) DG (M3) 5'C (Cladosporium sp.) DG (M3) 1 (Aspergillus sp.) And two bacterial: DG (B) 13 (Aurantimonas sp.) DG (G) 2B (Nocardiopsis sp.). These were grown on a larger scale of broth (500 mL) and extracted after 7, 14, 21 and 30 days of incubation. We carried out a cleaning process of these extracts by solid phase extraction (SPE) column of silica gel derivatized with C18 (35 mL of eluent: 100% H2O, MeOH/H2O 1:1 and MeOH 100%). The fractions generated were analyzed by HPLC-UV-MS trying to find characteristic profiles of secondary metabolites. From the DG sample (M3) 6'C (A + B), was isolated and identified the compound 13- deoxy-fomenona previously obtained by Tirilly et al. in 1983. Although this compound is not unheard of, no literature reports of studies involving bioassays cytotoxic against tumor cells and even this compound has been isolated from other species of microorganisms other than the fungus Dicyma pulvinata.
O cinema na aula de língua estrangeira: uma proposta didático-pedagógica para o ensino-aprendizagem de espanhol
(Universidade Federal de São Carlos, 2010-06-01) Stefani, Viviane Cristina Garcia de; Paula, Sandra Regina Buttros Gattolin de; https://lattes.cnpq.br/9228036521343293; https://lattes.cnpq.br/9946304206543559
The new configuration of the post-modern society has been demanding changes in the teaching extent. We are living in an era in which the school is not the main place where learning happens, and the knowledge is acquired through the interaction in the networks and communities of practice (FAIRCLOUGH, 2001) what makes us think about new ways of teaching and learning. It is necessary that the atmosphere of the classroom translates the transformations of the society, so that it can be considered as a community of practice, place where the knowledge is built. The role that the school should assume, together with the teacher, is to promote opportunities for the construction of new knowledge and for the approach of new cultures. Concerning teaching and learning of foreign language, the proximity among cultures is still more relevant. In new times the progress of the technology has been propitiating a narrowing in the contact among the people, and it is necessary to know not only the language, but also the culture of the other. Learning a foreign language means to familiarize with other manners of acting, thinking and communicating. We understand this practice can be favored by a communicative approach of teaching, whose focus is the united construction of the knowledge through the interaction and negotiation of meaning, so that the learning is relevant to the learner. When we think about procedures that make possible the implementation of a communicative teaching in agreement with the new demands of the modern society, so that it promotes opportunities for the construction of the knowledge through the interaction and negotiation meaning, and, at the same time, it can contemplate the approach of multiple linguistic and cultural varieties of the Spanish language, it seems opportune the use of the movie as a didactic resource. Although the films can be considered as an efficient didactic resource for the implementation of the communicative teaching of languages, for its entertainment nature and for its capacity of promoting the students' larger involvement in the accomplishment of significant activities, we noticed that its use is still quite limited in the teaching process. Considering that gap, the objective of this qualitative research of ethnographic base is investigate the use of the film The Motorcycle Diaries as didactic content in the context of Spanish teaching as foreign language, according to the theory of the significant learning (GEE, 2004; RICHARDS, 2005; SAVIGNON, 2001). The data were obtained by questionnaires, focal group and teacher notes, and they show that the film represents an effective way to present the linguistic input in a contextualized way, besides involving the students in interaction activities and negotiation of meaning, stimulating the critical thought and the world knowledge, and contributing significantly for the development of the student's autonomy as a language learner.
Estudos limnológicos e ecotoxicológicos da bacia do Alto Jacaré-Guaçu com ênfase no desenvolvimento de sedimentos artificiais para avaliação da toxicidade do cromo
(Universidade Federal de São Carlos, 2010-06-01) Campagna, Aline Fernanda; Verani, Nelsy Fenerich; https://lattes.cnpq.br/1862746100743391; https://lattes.cnpq.br/2484382689721394
This work aimed evaluates the Alto Jacaré-Guaçu rivers basin quality through physical, chemical and biological and ecotoxicological analysis. Samples of water and sediment were collected in April /07; July/07; October/07 and January/08 in fourteen locations. Moreover studies about survey/growth and gills morphology were performed in Danio rerio and Poecilia reticulata fishes exposed in the toxicity tests. The limnological data revealed the higher concentrations of metals and other variables in the October/07 and January/08 seasons, being over the limits established for aquatic organism s protection. In the water samples all metals were above the CONAMA 357/05, highlighting the values of cadmium and chromium. In the sediment, only cadmium and zinc values above the TEL however, the influence of high values of chromium in the collection sites were discriminated by multivariate analysis. The partial chronic toxicity tests performed using samples obtained from de natural environment revealed significant toxicity for a last one fish species and one parameter. Sublethal effects in the survey/growth and gills morphology were detected in the tests organisms on the different seasons to the each one specie. The sediment samples from July/07 and April/07 were more toxic to P. reticulate specie; however January/08 samples were more toxic to D. rerio. Chromium was chosen for the evaluation of toxicity in laboratory by spiking in artificial sediments. The results presented the suitability of the artificial sediments as to a substrate for toxicity tests and assisted in the interpretation of the chromium toxicity. The LC50;96h of chromium spiked in inorganic and organic sediments was 340,56 and <1440,0 mg.Kg-1 (C. xanthus); 1731,04 and 2263,54 mg.Kg-1 (D. rerio); 2263,54 mg/Kg and 1377,55 mg.Kg-1 (P. reticulata), respectively. The sublethal effects were detected at very low concentrations of bioavaliable chromium in sediments (0,8 to 1,425 mg/Kg) and dissolved in water (0,0275 to1,138 mg/L). The results suggesting that the chromium concentrations detected in the Alto Jacaré-Guaçu basin may present a risk to aquatic life.