Petrologia e geocronologia U-Pb do plúton granítico Serra da Rajada, porção central do domínio Rio Piranhas - Seridó, Província Borborema, NE do Brasil

The ediacaran plutonic activity related to the Brasilian/Pan-African orogeny is one of the most important geological features in the Borborema Province, represented along its extension by numerous batholiths, stocks, and dikes.The object of this study, the Serra Rajada Granitic Pluton (SRGP), located in the central portion of the Piranhas-Seridó River Domain is an example of this activity. This pluton has been the subject of cartographic, petrographic, geochronological and lithogeochemical studies and its rocks were characterized by two facies. First, the granitic facies were described as monzogranites consisting of K-feldspar, plagioclase (oligoclase - An23-24%), quartz and biotite (main mafic) and opaque minerals such as titanite, allanite, apatite, and zircon as accessories. Alteration minerals are chlorite, white mica and carbonate. Second, the dioritic facies consist of rocks formed by quartz diorite containing plagioclase (dominant mineral phase), quartz and K-feldspar. Biotite and amphibole are the dominant mafic minerals; and titanite, opaque minerals, allanite, zircon and apatite are the accessories. However, previous geological mapping work in the region also identified the presence of other lithostratigraphic units. These were described as gneisses and migmatites with undifferentiated amphibolite lenses related to the Caicó Complex (Paleoproterozoic) and metasedimentary rocks of the Seridó Group (Neoproterozoic) composed of paragneiss with calc-silicate lenses, muscovite quartzite and biotite schist (respectively, the Jucurutu formations, Equador and Seridó), the host rocks for the SRGP rocks. Leucomicrogranite and pegmatite dikes have also been identified, both related to the end of the Ediacaran magmatism and colluvial- eluvial and alluvial deposits related to Neogene and Quaternary, respectively. Lithogeochemical data on the SRGP granite facies, highlighted quite evolved rocks (SiO2 69% to 75%), rich in alkalis (Na2O+K2O ≥ 8.0%), depleted of MgO (≤ 0.45%), CaO (≤ 1.42%) and TiO2 (≤ 0.36%) and moderate levels of Fe2O3t (2.16 to 3.53%). They display transitional nature between metaluminous and peraluminous (predominance of the latter) with sub-alkaline/monzonitic (High K calcium-alkali) affinity. Harker diagrams show negative correlations for Fe2O3t, MgO, and CaO, indicating mafic and plagioclase fractionation. REE spectrum shows enrichment of LREE relative to heavy REE (LaN/YbN = 23.70 to 10.13), with negative anomaly in the Eu (Eu/Eu* = 0.70 to 0.23), suggesting fractionation or accumulation in the feldspars source (plagioclase). Data integration allows to correlate the SRGP rocks with those described as Calcium-Alkaline Suite of equigranular High K. The crystallization conditions of the SRGP rocks were determined from the integration of petrographic and lithogeochemical data. These data indicated intermediate to high conditions of ƒO2 (mineral paragenesis titanite + magnetite + quartz), parent magma saturated in H2O (early biotite crystallization), tardi-magmatic processes of fluids rich in ƒCO2, H2O and O2 causing part of the mineral assembly to change (plagioclase carbonation and saussuritization, biotite chloritization and opaques Sphenitization). Thermobarometrical conditions were estimated based on geochemical parameters (Zr and P2O5) and CIPW normative minerals, with results showing the liquidus minimum temperature of about800°C and the solidus temperature of approximately 700°C. The final/minimum crystallization pressure are suggested to be between 3 and 5 Kbar. The presence of zoned minerals (plagioclase and allanite) associated with lithogeochemical data in bi-log diagrams for Rb vs. Ba and Rb vs. Sr suggest the role of fractional crystallization as the dominant process in the magmatic evolution of SRGP. U-Pb Geochronological and Sm-Nd isotope studies indicated, respectively, the crystallization age of biotite monzogranite as 557 ± 13 Ma, with TDM model age of 2.36 Ga, and εNd value of -20.10 to the crystallization age, allowing to infer paleoproterozoic crustal source for the magma.

Petrologia e geocronologia U-Pb do plúton granítico Serra da Rajada, porção central do domínio Rio Piranhas - Seridó, Província Borborema, NE do Brasil

The ediacaran plutonic activity related to the Brasilian/Pan-African orogeny is one of the most important geological features in the Borborema Province, represented along its extension by numerous batholiths, stocks, and dikes.The object of this study, the Serra Rajada Granitic Pluton (SRGP), located in the central portion of the Piranhas-Seridó River Domain is an example of this activity. This pluton has been the subject of cartographic, petrographic, geochronological and lithogeochemical studies and its rocks were characterized by two facies. First, the granitic facies were described as monzogranites consisting of K-feldspar, plagioclase (oligoclase - An23-24%), quartz and biotite (main mafic) and opaque minerals such as titanite, allanite, apatite, and zircon as accessories. Alteration minerals are chlorite, white mica and carbonate. Second, the dioritic facies consist of rocks formed by quartz diorite containing plagioclase (dominant mineral phase), quartz and K-feldspar. Biotite and amphibole are the dominant mafic minerals; and titanite, opaque minerals, allanite, zircon and apatite are the accessories. However, previous geological mapping work in the region also identified the presence of other lithostratigraphic units. These were described as gneisses and migmatites with undifferentiated amphibolite lenses related to the Caicó Complex (Paleoproterozoic) and metasedimentary rocks of the Seridó Group (Neoproterozoic) composed of paragneiss with calc-silicate lenses, muscovite quartzite and biotite schist (respectively, the Jucurutu formations, Equador and Seridó), the host rocks for the SRGP rocks. Leucomicrogranite and pegmatite dikes have also been identified, both related to the end of the Ediacaran magmatism and colluvial- eluvial and alluvial deposits related to Neogene and Quaternary, respectively. Lithogeochemical data on the SRGP granite facies, highlighted quite evolved rocks (SiO2 69% to 75%), rich in alkalis (Na2O+K2O ≥ 8.0%), depleted of MgO (≤ 0.45%), CaO (≤ 1.42%) and TiO2 (≤ 0.36%) and moderate levels of Fe2O3t (2.16 to 3.53%). They display transitional nature between metaluminous and peraluminous (predominance of the latter) with sub-alkaline/monzonitic (High K calcium-alkali) affinity. Harker diagrams show negative correlations for Fe2O3t, MgO, and CaO, indicating mafic and plagioclase fractionation. REE spectrum shows enrichment of LREE relative to heavy REE (LaN/YbN = 23.70 to 10.13), with negative anomaly in the Eu (Eu/Eu* = 0.70 to 0.23), suggesting fractionation or accumulation in the feldspars source (plagioclase). Data integration allows to correlate the SRGP rocks with those described as Calcium-Alkaline Suite of equigranular High K. The crystallization conditions of the SRGP rocks were determined from the integration of petrographic and lithogeochemical data. These data indicated intermediate to high conditions of ƒO2 (mineral paragenesis titanite + magnetite + quartz), parent magma saturated in H2O (early biotite crystallization), tardi-magmatic processes of fluids rich in ƒCO2, H2O and O2 causing part of the mineral assembly to change (plagioclase carbonation and saussuritization, biotite chloritization and opaques Sphenitization). Thermobarometrical conditions were estimated based on geochemical parameters (Zr and P2O5) and CIPW normative minerals, with results showing the liquidus minimum temperature of about800°C and the solidus temperature of approximately 700°C. The final/minimum crystallization pressure are suggested to be between 3 and 5 Kbar. The presence of zoned minerals (plagioclase and allanite) associated with lithogeochemical data in bi-log diagrams for Rb vs. Ba and Rb vs. Sr suggest the role of fractional crystallization as the dominant process in the magmatic evolution of SRGP. U-Pb Geochronological and Sm-Nd isotope studies indicated, respectively, the crystallization age of biotite monzogranite as 557 ± 13 Ma, with TDM model age of 2.36 Ga, and εNd value of -20.10 to the crystallization age, allowing to infer paleoproterozoic crustal source for the magma.

Petrologia e geoquímica do magmatismo ediacarano Serra do Caramuru, Rio Grande do Norte, NE do Brasil

The Serra do Caramuru and Tapuio stocks, located in the extreme NE of Rio Piranhas-Seridó Domain (RN), are representative of the Ediacaran-Cambrian magmatism, an important magmatic feature of the Brasilian / Panafrican orogeny of the Borborema Province. These bodies are lithologically similar, intrusive in paleoproterozoic gneiss embasement, being separated by a thin belt of mylonitic orthogneiss. The field relations show a magmatic stratigraphy initiated by dioritic facies that coexists with the porphyritic granitic and equigranular granitic I facies, and less frequently with equigranular granitic II facies. These rocks are crosscut by late granitic dykes and sheets with NE-SW / NNE-SSW orientation. The dioritic facies (diorite, quartz diorite, quartz monzodiorites, tonalite and granodiorite) is leucocratic to melanocratic, rich in biotite and hornblende. The granitic facies are hololeucocratic to leucocratic, and have biotite ± hornblende. Petrographic and geochemical (whole rock) data, especially from Serra do Caramuru pluton, suggest fractionation of zircon, apatite, clinopyroxene (in diorites), opaque minerals, titanite, biotite, hornblende, allanite, plagioclase, microcline and garnet (in dykes). The behavior of trace elements such as Zr, La and Yb indicates that the dioritic magma does not constitute the parental magma for the granitic facies. On the other hand, the granitic facies seems to be cogenetic to each other, displaying differentiation trends and very similar rare earth elements (REE) spectra [12.3≤(La/Yb)N≤190.8; Eu/Eu*=0.30-0.68]. Field relationships and REE patterns [6.96≤(La/Yb)N≤277.8; Eu/Eu*=0.18-0.58] demonstrate that the granitic dykes and sheets are not cogenetically related to the Serra do Caramuru magmatism. The dioritic facies is metaluminous (A/CNK = 0.88-0.74) and shoshonitic, whereas the granitic ones are metaluminous to peraluminous (A/CNK = 1.08-0.93) and high potassium calc-alkaline. Dykes and sheets are strictly peraluminous (A/CNK = 1.01-1.04). Binary diagrams relating compatible and incompatible trace elements and microtextures indicate the fractional crystallization as the dominant mechanism of magmatic evolution of the various facies. The Serra do Caramuru and Tapuio stocks have well preserved magmatic fabric, do not show metamorphic minerals and are structurally isotropic, showing crosscutting contact with the ductile fabric of the basement. These observations lead to interpretate a stage of relative tectonic stability, consistent with the orogenic relaxation period of the Brasiliano / Pan-African orogeny. Chemical plots involving oxides and trace elements indicate late to post-collisional emplacement. In this context, the assumed better mechanism to describe the stocks emplacement within an extensional T Riedel joint, with ENE-WSW extensional vector. The U-Pb zircon age of 553 ± 10 Ma allows correlating the Serra do Caramuru magmatism to the group of post-collisional bodies, equigranular high potassium calc-alkaline granites of the NE of Rio Piranhas-Seridó Domain.

Petrologia e geoquímica do magmatismo ediacarano Serra do Caramuru, Rio Grande do Norte, NE do Brasil

The Serra do Caramuru and Tapuio stocks, located in the extreme NE of Rio Piranhas-Seridó Domain (RN), are representative of the Ediacaran-Cambrian magmatism, an important magmatic feature of the Brasilian / Panafrican orogeny of the Borborema Province. These bodies are lithologically similar, intrusive in paleoproterozoic gneiss embasement, being separated by a thin belt of mylonitic orthogneiss. The field relations show a magmatic stratigraphy initiated by dioritic facies that coexists with the porphyritic granitic and equigranular granitic I facies, and less frequently with equigranular granitic II facies. These rocks are crosscut by late granitic dykes and sheets with NE-SW / NNE-SSW orientation. The dioritic facies (diorite, quartz diorite, quartz monzodiorites, tonalite and granodiorite) is leucocratic to melanocratic, rich in biotite and hornblende. The granitic facies are hololeucocratic to leucocratic, and have biotite ± hornblende. Petrographic and geochemical (whole rock) data, especially from Serra do Caramuru pluton, suggest fractionation of zircon, apatite, clinopyroxene (in diorites), opaque minerals, titanite, biotite, hornblende, allanite, plagioclase, microcline and garnet (in dykes). The behavior of trace elements such as Zr, La and Yb indicates that the dioritic magma does not constitute the parental magma for the granitic facies. On the other hand, the granitic facies seems to be cogenetic to each other, displaying differentiation trends and very similar rare earth elements (REE) spectra [12.3≤(La/Yb)N≤190.8; Eu/Eu*=0.30-0.68]. Field relationships and REE patterns [6.96≤(La/Yb)N≤277.8; Eu/Eu*=0.18-0.58] demonstrate that the granitic dykes and sheets are not cogenetically related to the Serra do Caramuru magmatism. The dioritic facies is metaluminous (A/CNK = 0.88-0.74) and shoshonitic, whereas the granitic ones are metaluminous to peraluminous (A/CNK = 1.08-0.93) and high potassium calc-alkaline. Dykes and sheets are strictly peraluminous (A/CNK = 1.01-1.04). Binary diagrams relating compatible and incompatible trace elements and microtextures indicate the fractional crystallization as the dominant mechanism of magmatic evolution of the various facies. The Serra do Caramuru and Tapuio stocks have well preserved magmatic fabric, do not show metamorphic minerals and are structurally isotropic, showing crosscutting contact with the ductile fabric of the basement. These observations lead to interpretate a stage of relative tectonic stability, consistent with the orogenic relaxation period of the Brasiliano / Pan-African orogeny. Chemical plots involving oxides and trace elements indicate late to post-collisional emplacement. In this context, the assumed better mechanism to describe the stocks emplacement within an extensional T Riedel joint, with ENE-WSW extensional vector. The U-Pb zircon age of 553 ± 10 Ma allows correlating the Serra do Caramuru magmatism to the group of post-collisional bodies, equigranular high potassium calc-alkaline granites of the NE of Rio Piranhas-Seridó Domain.

Relações interétnicas em conflito entre Makuxi e Wapixana na terra indígena Raposa Serra do Sol

This dissertation present an analysis of the interethnic conflict between Makuxi and Wapixana at the current moment in the Maloca of the Adobe, Aboriginal Land Fox-Mountain range of the Sun, in the State of Roraima. The theoretical field was boarded in the Ethnology, pursuing situations in local history, with edges in ethno-history. The research elapsed of the deepening necessity on the social relations and aboriginal politics, for the intercultural professional exercise of educator, appealing the bibliographical survey and participant comment as method; not directive interviews, photographs, filmings and daily register in of field, as techniques carried through in the period of 2006 to 2007. Although to inhabit in the same area and to establish marriages between itself, individuals and groups express tensions, aggravated with the landmark and legal recognition of the area, which generated inter dispute and intraetnias, mainly with the intrusion of farmers, rizicultores and the form of governmental influence. A relation of rivalry, individual and collective was evidenced, suggesting the strengthenig and not it fractionly, of the fights external politics, interns and in way to the cultural diversity and social adversity

Caracterização geológica e geofísica da área do porto da Figueira da Foz

No âmbito de um projeto realizado para a Administração Portuária do Porto da Figueira da Foz, foram recolhidos dados geofísicos no offshore da costa da Figueira da Foz, utilizando um sistema combinado de sonar de varrimento lateral e de sísmica de alta resolução com o objetivo de compreender a distribuição de sedimentos ao longo do fundo marinho e assim entender melhor a sua origem. Os dados de varrimento lateral foram processados, analisados e representados em mosaicos recorrendo ao software integrado TRINTON Prespective. Foram colhidas 10 amostras de sedimentos de fundo que foram analisadas do ponto de vista granulométrico e que foram usadas para a calibração dos mosaicos do sonar de varrimento lateral de modo a produzir um mapa semi-quantitativo de classificação dos sedimentos de fundo. Os dados de reflexão sísmica foram processados e analisados através dos softwares SPW e RadExPro. Os mapas de sonar de varrimento lateral produzidos (mosaicos) mostram uma relação entre o tamanho de grão e composição dos depósitos de plataforma interna e os processos geológicos que ocorrem na zona costeira adjacente. Também se verifica uma relação entre a orientação da costa e a sua consequente exposição às ondas incidentes, e como isso afeta e altera a distribuição do tamanho grão. Neste contexto, a interpretação combinada dos mosaicos do sonar de varrimento lateral com os dados de granulometria e a batimetria dos sedimentos permitiram uma cartografia interpretativa detalhada da morfologia do mar, uma melhor compreensão do controlo da linha costeira na propagação das ondas e correntes e, por conseguinte, na transferência de sedimento no litoral. Os dados de sísmica permitem ainda verificar a espessura das várias camadas geológicas em profundidade.

Distribuição dos metais nas poeiras colhidas em Estarreja: estudo da mobilidade e impacto potencial dos metais no ambiente

As poeiras urbanas, vulgarmente designadas na literatura por street dusts ou road dusts, são misturas heterogêneas de partículas minerais do solo e partículas resultantes do tráfego, formando um material com características únicas e específicas de cada local. Estas partículas, geralmente enriquecidas com elementos potencialmente tóxicos, quando inaladas ou ingeridas poderão ser um risco para a saúde das populações. Neste trabalho foram recolhidas 21 amostras de poeiras urbanas na cidade de Estarreja assim como amostras representativas de partículas relacionados com o tráfego (poeiras resultante do desgaste dos travões e das marcações dos pavimentos e estradas) com o objetivo de investigar a contribuição relativa destas partículas no comportamento geoquímico dessas amostras e o risco associado para as populações locais. Para a concretização do objetivo proposto caracterizou-se química e mineralogicamente as amostras de poeiras urbanas e as partículas relacionadas com o tráfego e avaliou-se a disponibilidade e bioacessibilidade para três elementos considerados potencialmente tóxicos (Cu, Pb e Zn) usando uma combinação de ensaios: (a) digestão ácida; (b) extração sequencial para identificar o fracionamento do Cu, Pb e Zn nas diferentes fases-suporte dos metais, e (c) bioaccessibilidade oral in vitro. Os resultados da análise química mostram que as poeiras dos travões apresentam concentrações elevadas em Fe, Cu, Zn, Mn, Ba, Sb, Cr e Ni sendo de referir diferenças composicionais significativas entre as amostras estudadas. A amostra de tinta contém teores elevados de Ba, Ca, Ti e Pb e também pode conter outros elementos tais como Co, Cr, Cu, Mn. Mineralogicamente constata-se que as amostras de poeiras dos travões tem uma composição mineralógica semelhante mostrando que são constituídas por uma elevada percentagem de material de baixa cristalinidade, grafite e óxidos/hidróxidos de Fe amorfos. A amostra de tinta de marcação dos pavimentos das estradas é composta por material mais cristalino do que a poeira dos travões e é essencialmente constituída por carbonatos (maioritariamente dolomite) e também por barite (em menor quantidade). Os resultados obtidos nas amostras de poeiras urbanas indicam a existência de associações de elementos que definem claramente a componente geogénica e/ou antropogénica e apontam para diferenças entre essas associações nas duas frações estudadas (250 m e 63 m). A heterogeneidade das poeiras é revelada pela existência de partículas com origem geogénica (por exemplo quartzo e aluminossilicatos), de partículas com características marcadamente antropogénicas (partículas enriquecidas em Fe, Pb, Zn e Cu) ou ainda de partículas com origem mista (óxidos de Fe e Ti). Os resultados da extração química seletiva sequencial permitiu concluir que, nas amostras em estudo, as fases de troca e ácido-solúveis são as fases suporte mais importantes para o Cu, Pb e Zn Os resultados dos ensaios de bioacessibilidade mostraram também que uma percentagem significativa de Cu, Pb e Zn total está disponível para absorção gástrica. Este estudo destaca também a necessidade de se caracterizar em detalhe as propriedades intrínsecas das partículas antrópicas presentes nas poeiras urbanas, de forma a compreender as variações da fração bioacessível nos diferentes elementos estudados assim como nas diferentes frações.

Produção de lipidios funcionais por ação de lipase fúngica

A modificação estrutural de óleos e gorduras é uma das principais áreas de interesse de pesquisa em diferentes setores industriais. No caso da indústria de alimentos, a interesterificação é empregada para melhorar propriedades nutricionais e funcionais, em que se obtêm compostos diferentes dos que lhes deram origem. As lipases microbianas são os biocatalisadores mais utilizados industrialmente, por serem mais estáveis, específicas e com propriedades bem mais diversificadas que as lipases de outras fontes. Este trabalho objetivou, primeiramente, a caracterização da gordura da pele de frango (GPF) e sua comparação com óleo de soja, como referência, visando a utilização de GPF em reações de interesterificação. Para isto foram caracterizados quanto aos índices de rancidez hidrolítica e oxidativa, bem como de matéria insaponificável, índices de saponificação, refração e iodo. Foi realizado ainda o fracionamento e perfil de ácidos graxos destes lipídios e suas frações, com o cálculo de seus índices nutricionais. Foi verificado que a GPF apresentou qualidade satisfatória devido aos baixos índices de acidez (0,65 g ácido oleico.100 g -1 ), peróxido (2,14 meq.kg-1 ), p-anisidina (0,70 unidades de absorvância.g-1 ), além de fonte de ácidos graxos mono-insaturados (40%), sendo fonte promissora para estudos de interesterificação. Em um segundo momento o objetivo foi produzir lipídios modificados ricos em ácidos graxos essenciais a partir da gordura da pele de frango e ácidos graxos ramificados, utilizando lipase sn-1,3 específica e interesterificação do tipo acidólise. Foram estudados os fatores concentração de enzima, adição de água, proporção de substratos e tempo, segundo um planejamento experimental fatorial completo 2 4 . As separações analíticas foram executadas em placas de cromatografia de camada delgada, sendo as frações posteriormente extraídas, ressuspensas e injetadas no cromatógrafo a gás. Foi verificado que a adição de água ao meio reacional apresentou efeito significativo (p<0,05) para todos ácidos graxos avaliados dos triacilgliceróis, sendo que para o ácido essencial linoleico (C18:2) o efeito do tempo de reação também foi significativo, sendo verificado que quanto maior o tempo de reação, menor a quantidade de água a ser adicionada. Em um terceiro momento, o objetivo foi produzir éster fenólico a partir do DHCA, além de realizar reações de transesterificação deste éster com tricaprilina. Para a reação de transesterificação, foi utilizado um delineamento composto central rotacional (DCCR) variando a quantidade de enzima, tempo de reação e temperatura sobre a resposta (%) dos reagentes consumidos. A lipase Novozym® 435 de Candida antarctica foi utilizada como catalisador de todas reações. Foi verificado que a maior produção de éster (50%) ocorreu em oito dias. Nas reações de transesterificação, as relações molares em que houve maior consumo do éster produzido foram 1:5 e 1:10, sendo obtidos 21,1% e 29,6% de residual de dihidrocafeato de octila, respectivamente em 24 h. Foi observado que em altas temperaturas e tempo superior a 26 h, houve o menor residual de dihidrocafeato de octila (18,2%). Foram identificados três diferentes compostos fenólicos, contendo em sua estrutura dihidrocafeato de octila e ácido caprílico.

Avaliação do extrato do fungo caripia montagnei e de agonistas de PPAR - α no processo inflamatório

The mushrooms have been object of intense research in view of its potential raising of application in different sectors of the pharmacology and alimentary industry. Among diverse bioactive composites of polyssacharides nature that exist in the fungus the glucans are much searched. These are polymers of glucose and classified as the type of glicosidic linking [α, β]. Peroxisome proliferator-activated receptors (PPARs), ranscription factors belonging to the family of nuclear receptors that bind themselves o specific agonists, have shown their importance in controlling the inflammatory process. The aim of this study was to perform a chemical characterization of extract rom the mushroom Caripia montagnei, assess its antiinflammatory and antibacterial effect and determine if this effect occurs via PPAR. This mushroom is composed of carbohydrates (63.3±4.1%), lipids (21.4l±0.9%) and proteins (2.2± 0.3%). The aqueous solution resulting from the fractionation contained carbohydrates (98.7±3.3%) and protein (1.3±0.25%). Analyses of infrared spectrophotometry and of nuclear magnetic esonance demonstrated that the extract of mushroom C. montagnei is rich in β-glucans. In hioglycolate-induced peritonitis, the C. montagnei glucans (50 mg/kg) educed the inflammatory process in 65.5±5.2% and agonists, pharmacological igands, for PPAR: Wy-14643 (49.3±6.1%), PFOA (48.9±3.8%) and clofibrate in 45.2±3.2%. Sodium diclofenac showed a reduction of 81.65±0.6%. In the plantar edema, the glucans from C. montagnei (50 mg/kg) and L-NAME reduced the edema to a similar degree 91.4±0.3% and 92.8±0,5 %, respectively. In all the groups tested, nitric oxide (NO), an inflammation mediator, showed a significant reduction in the nitrate/nitrite levels when compared to the positive control (P<0.001). The C. montagnei glucans did not show cytotoxicity in the concentrations tested (2.5, 5.0, 10.0, 20.0 and 40.0 µg/100 µL). Antibacterial activity demonstrated that, unlike total extract, there was no inhibition of bacterial growth. The C. montagnei glucans show great potential for antiinflammatory applications. This effect suggests that it is mediated by PPAR activation and by COX and iNOS inhibition

Homogalactanas sulfatadas da alga Codium isthmocladum com atividade anticoagulante

Since the first description of sulfated polysaccharides from seaweeds, the biological activities of these compounds have been evaluated under different aspects and experimental procedures. Among the broad biological activities presented by seaweed polysaccharides, anticoagulant action appears as a promising function. In this present study we have obtained sulfated polysaccharides from the green seaweed Codium isthmocladium by proteolytic digestion, followed by separation into five fractions (0.3, 0.5, 0.7, 0.9 and 1.2) by sequential acetone precipitation. The chemical analyses have demonstrated that all fractions are composed mainly by sulfated polysaccharides. The anticoagulant activity of these fractions was determined by activated partial thromboplastin time (aPTT) and prothrombin time test (PT) using citrate normal human plasma. None fraction has shown anticoagulant activity by PT test. Furthermore, all of them have shown anticoagulant activity by aPTT test. These results indicated that the molecular targets of these sulfated polysaccharides are mainly in the intrinsic via of the coagulation cascade. Agarose gel electrophoresis in 1,3-diaminopropane acetate buffer, pH 9.0, stained with 0.1% toluidine blue showed the presence of two or three bands in several fractions while the fraction 0.9 showed a single spot. By anion exchange chromatography, the acid polysaccharides from the 0.9 acetone fraction were separated into two new fractions eluted respectively with 2.0 and 3.0 M NaCl. These compounds showed a molecular weight of 6.4 and 7.4 kDa respectively. Chemical analyses and infrared spectroscopy showed that Gal 1 and Gal 2 are sulfated homogalactans and differ one from the other in degree and localization of sulfate groups. aPPT test demonstrated that fractions 2,0 and 3,0M (Gal1 and Gal 2, respectively) have anticoagulant activity. This is the first time that anticoagulant sulfated homogalatans have been isolated from green algae. To prolong the coagulation time to double the baseline value in the aPTT, the required amount of sulfated galactan 1 (6,3mg) was similar to low molecular heparin Clexane®, whereas only 0,7mg of sulfated galactan 2 was needed to obtain the same effect. Sulfated galactan 2 in high doses (250mg) induces platelet aggregation. These results suggest that these galactans from C. isthmocladum have a potential application as an anticoagulant drug

Uma Lectina D-lactose específica da esponja marinha Cinachyrella apion: purificação, caracterização e interação com Leishmania chagasi

Four different sponge species were screened using Ouchterlony agarose gel and immunodiffusion tests to identify cross-reactivity with the polyclonal antibody IgG anti-deglicosilated CvL, a lectin from Cliona varians. Crude extract from the sponge Cinachyrella apion showed cross-reactivity and also a strong haemmaglutinating activity towards human erythrocytes of all ABO groups. Thus, it was submitted to acetone fractionation, IgG anti-deglicosilated CvL Sepharose affinity chromatography, and Fast Protein Liquid Chromatography (FPLC-AKTA) gel filtration on a Superose 6 10 300 column to purify a novel lectin. C. apion lectin (CaL) agglutinated all types of human erythrocytes with preference for papainized type A and O erythrocytes. The haemagglutinating activity is independent of Ca2+, Mg2+ and Mn2+ ions, and it was strongly inhibited by the disaccharide D-lactose, up to a minimum concentration of 6.25 mM. CaL molecular mass determined by FPLC-AKTA gel filtration on a Superose 12 10 300 column and SDS gel electrophoresis was approximately 124 kDa, consisting of eight subunits of 15.5 kDa, assembled by hydrophobic interactions. The lectin was relatively heat- and pH-stable. Leishmania chagasi romastigotes were agglutinated by CaL, indicating that lactose receptors could be presented in this parasite stage. These findings are indicative of the physiological defense roles of CaL and its possible use in the antibiosis of pathogenic protozoa

Purificação, caracterização e atividade bioinseticida de um inibidor de tripsina de sementes de Crotalaria pallida

A proteinaceous trypsin inhibitor was purified from Crotalaria pallida seeds by ammonium sulphate fractionation, affinity chromatography on immobilized Trypsin-Sepharose and TCA precipitation. The trypsin inhibitor, named ITC, had Mr of 32.5 kDa by SDS-PAGE and was composed by two subunits with 27.7 and 5.6 kDa linked by disulphide bridges, a typical characteristic of Kunitz-Inhibitor family. ITC was stable until 50°C, and at 100°C its residual activity was of about 60%. Also, ITC was stable at pHs 2 to 12. The inhibition of trypsin by ITC was non-competitive, with a Ki of 8,8 x 10-7M. ITC inhibits weakly other serine proteinases such as chymotrypsin and elastase. The inhibition of papain (44% of inhibition), a cysteine proteinase was an indicative of the bi-functionality of ITC. In vitro assays against digestive proteinases from several Lepdoptera, Diptera and Coleoptera pests were made. ITC inhibited in 100% digestive enzymes of Ceratitis capitata (fruit fly), Spodoptera frugiperda and Alabama argillacea, the last one being a cotton pest. It also inhibited in 74.4% Callosobruchus maculatus (bean weevil) digestive enzymes, a Coleoptera pest. ITC, when added in artificial diet models, affected weakly the development of C. capitata larvae and it had a WD50 of 2.65% to C. maculatus larvae

Purificação e caracterização de uma ß-glucuroniodase extraída do molusco Mesogastropoda Ampularidae Pomacea sp

This work studies the involved enzymatic way in the metabolism of glycosaminoglycans sulfateds in the mollusc Pomacea sp. Had been identified endoglycosidases and exoglycosidases in the enzymatic extract of the mollusc Pomacea sp by means of hydrolysis activity in condroitim sulphate of whale cartilage and of the p-Nitrofenil-β-glucuronide, respectively. The enzymatic extracts qere obtained of Pomacea sp. being used of 0.1 sodium acetate buffer, pH 5.0 and later centrifugated the 8,000 x g and the presents proteins in the sobrenadante were submitted to the fractionament with two crescents ammonium sulphate concentrations, the visualized activity biggest in the F2 fraction (50-80%). The β-glucuronidase (F3) was isolated in gel chromatography filtration Biogel 1.5m, the purification degree was ratified in Chromatography Liquid of high efficiency (HPLC). The enzyme was purificated 6.362,5 times with 35,6% yield. The β -glucuronidase isolated in this work showed a molecular mass of 100 kDa, determined for eletroforese in poliacrilamida gel . The determination of the ideal kinetic parameters for the catalysis of the p-nitrofenil- β -glucuronide for β-glucuronidase, showed excellent activity in pH 5,0 and temperature 65ºC for 6 hours and apparent Km of 72 x 10-2 mM. It is necessary for the total degradation of 3mM of p-N-β-glucoronide, the amount of 1,2μg of ss-glucuronidase. The BaCl2 increased the activity of ss-glucuronidase, and the activity was inhibited completely by the composites SDS and NaH2PO4

ABUNDÂNCIA NATURAL DE 15N E FORMAS DE NITROGÊNIO EM ARGISSOLO CULTIVADO COM EUCALIPTO E ACÁCIA

O nitrogênio e um dos nutrientes mais demandados pelas espécies vegetais, sua presença no solo, sob formas orgânicas ou minerais disponíveis para as plantas, está vinculada à qualidade e quantidade dos resíduos vegetais aportados ao solo. O estudo teve o objetivo de avaliar a influência do cultivo do eucalipto e da acácia na composição das formas orgânicas e inorgânicas de N e, na abundância natural de 15N em um Argissolo Amarelo. Para isso, foram coletadas amostras de solo e serapilheira em monocultivos do Eucalyptus urograndis (clone do Eucalyptus urophylla S. T. Blake x Eucalyptus grandis W. Hill ex Spreng) de ciclo curto (sete anos), sistemas de cultivo de rotação com acácia ( Acacia mangium Willd.) após monocultivo de eucalipto, monocultivo de eucalipto de ciclo longo (24 anos) e mata nativa (Mata Atlântica) como condição original de solo do litoral Norte do Espírito do Santo. Foram avaliados os teores de C orgânico total, N total, N-NH4+, N-NO3-, relação C/N, fracionamento do N orgânico e abundância natural de 15N no solo e serapilheira. Das formas de N-orgânico hidrolisado, o N-amino foi a fração que apresentou maior contribuição (39%), seguida pela fração de N-não identificado (27%), da fração N-amida (18%) e N-hexosamina (15%). O povoamento de acácia promoveu menor abundância natural de 15N e maiores teores de N total e C orgânico no solo e aumentou as formas orgânicas de N-hidrolisado, quando comparado àqueles de eucalipto de ciclo curto. Isso indica o aumento de formas lábeis de N orgânico no solo para as plantas e redução da humificação da matéria orgânica do solo (MOS) de acácia. Nesse sentido, a rotação de cultivos florestais com acácia após eucalipto de ciclo curto contribuiu para o aumento de formas orgânicas no solo, importantes para a nutrição de plantas, por serem potenciais fontes de nutrientes às plantas em curto período de tempo.

Atividades biológicas de polissacarídeos sulfatados extraídos da alga vermelha Gracilaria caudata

In recent years, sulfated polysaccharides (SP) from marine algae have emerged as an important class of natural biopolymers with potential pharmacology applications. Among these, SP isolated from the cell walls of red algae have been study due to their anticoagulant,antithrombotic and anti-inflammatory activities. In the present study, three sulfated polysaccharides fractions denominated F1.5v, F2.0v and F3.0v were obtained from seaweed G. caudate by proteolysis followed to acetone fractionation. Gel electrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9,0, stained with 0.1% toluidine blue, showed the presence of SP in all fractions. The chemical analysis demonstrated that all the fractions are composed mainly of galactose. These compounds were evaluated in anticoagulant, antioxidant and antiproliferative activities. In anticoagulant activity evaluated through aPTT and PT tests, no one fractions presented anticoagulant activity at tested concentrations (0.1 mg/mL; 1.0 mg/mL; 2.0 mg/mL).The antioxidant activities of the three fractions were evaluated by the following in vitro systems: Total antioxidant capacity, superoxide and hydroxyl radical scavenging, ferrous chelating activity and reducing power. The fractions were found to have different levels of antioxidant activity in the systems tested. F1.5v shows the highest activity, especially in the ferrous chelating system, with 70% of ferrous inhibiting at 1.0 mg.mL-1. Finally, all the fractions showed dose-dependent antiproliferative activity against HeLa cells. The fractions F1.5v and F2.0v presented the highest antiproliferative activity at 2.0 mg/mL with 42.7% and 37.0% of inhibition, respectively. Ours results suggests that the sulfated polysaccharides from seaweed G. caudata are promising compounds in antioxidant and/or antitumor therapy