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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

CaracterizaÃÃo fÃsico-quÃmica e efeito sobre bactÃrias orais de uma lectina de sementes de Andira surinamensis (Bondt) Splitg. ex Amshoff. / Physicochemical Characterization and the Effect on Oral Bacteria Strains of a seed lectin from Andira surinamensis (BONDT) SPLITG. ex AMSHOFF

Camila Bezerra Nobre 27 February 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As sementes de Andira surinamensis (Bondt) Splitg. ex Amshoff, uma espÃcie pertencente à famÃlia Leguminosae, subfamÃlia Papilionoideae, tribo Dalbergieae, possuem uma lectina glicose/manose especÃfica, que aglutina eritrÃcitos de coelhos nativos ou tratados com enzimas proteolÃticas. A lectina de sementes de Andira surinamensis foi purificada atravÃs de cromatografia de afinidade em matriz de Sepharose-Manose seguida por cromatografia de troca iÃnica em matriz de DEAE-Sephacel. Esse procedimento resultou na lectina purificada, nomeada de ASL. O processo de purificaÃÃo da ASL foi monitorado pela atividade hemaglutinate especÃfica e SDS-PAGE, onde se observou que essa lectina à composta por seis bandas protÃicas, uma de maior peso molecular aparente de aproximadamente 20 kDa e outras cinco bandas de menor peso molecular aparente entre 15 e 12 kDa. A massa molecular intacta da lectina purificada foi determinada atravÃs da tÃcnica de espectrometria de massa com IonizaÃÃo por Eletrospray (ESI). A anÃlise do espectro de massa intacta mostrou a presenÃa de dois Ãons majoritÃrios de massa molecular de 12.220+ 2 e 13.258 + 2 Da. ASL tambÃm teve sua estrutura primÃria parcialmente sequenciada atravÃs de espectrometria de massa sequencial. Essa lectina à uma glicoproteÃna e demonstra elevada estabilidade, sendo capaz de manter sua atividade hemaglutinante em uma ampla faixa de pH e apÃs exposiÃÃo a temperaturas de atà 80 ÂC por 1hora. ApÃs diÃlise contra o agente quelante EDTA, ASL teve sua atividade hemaglutinante diminuÃda, porÃm recuperou sua atividade apÃs a adiÃÃo de metais, mostrando-se dependente de cÃtions metÃlicos divalentes. Foi avaliado tambÃm o efeito da ASL no crescimento planctÃnico bacteriano e na formaÃÃo de biofilmes e observou-se que ela interferiu no crescimento planctÃnico de duas diferentes cepas bacterianas gram-positivas (Streptococcus mitis e Streptococcus salivarius) e na formaÃÃo de biofilme por Staphylococcus aureus e Streptococcus salivarius. / Andira surinamensis (Bondt) Splitg. ex Amshoff seeds, a species belonging to the Leguminosae family, Papilionoideae subfamily, Dalbergieae tribe, have a glucose/mannose specific lectin rabbit erythrocytes that agglutinate native or treated with proteolytic enzymes. The lectin from Andira surinamensis seeds was purified by affinity chromatography on Mannose-Sepharose matrix followed by ion exchange chromatography on DEAE-Sephacel matrix. This procedure resulted in a purified lectin, named ASL. ASL purification process was monitored by specific hemagglutinating activity and SDS-PAGE, where it was observed that this lectin is composed of six protein bands, a higher molecular weight of approximately 20 kDa and five other bands of lower apparent molecular weight between 15 and 12 kDa.The intact molecular mass of the purified lectin was determined by mass spectrometry with electrospray ionization (ESI). The analysis of the intact mass spectrum showed the presence of two majority ions of molecular mass 12.220+ 2 and 13.258 + 2 Da. ASL also had its primary structure partially sequenced by mass spectrometry sequence. This lectin is a glycoprotein and shows high stability, being able to maintain their hemagglutinating activity in a wide pH range and after exposure to temperatures up to 80 ÂC for 1 hour. After dialysis against the chelating agent EDTA, ASL had its hemagglutinating activity decreased, but recovered its activity after the addition of metals, being dependent on divalent metal cations. We also evaluate the effect of ASL on planktonic bacterial growth and biofilm formation and found that it interfered with the growth of two different planktonic gram-positive bacterial strains (Streptococcus mitis and Streptococcus salivarius) and biofilm formation by Stafilococcus aureus e Streptococcus salivarius.
2

ContribuiÃÃo ao conhecimento quÃmico de plantas do nordeste:Andira surinamensis e Piper divaricatum / Contribution to chemical knowledge of plants of northeast: Andira surinamensis e Piper divaricatum

Josà Gustavo Lima de Almeida 12 July 2007 (has links)
nÃo hà / Este trabalho descreve o estudo fitoquÃmico das cascas e do lenho de Andira surinamensis (Leguminosae), bem como a composiÃÃo quÃmica volÃtil dos Ãleos essenciais das folhas e frutos de Piper divaricatum G. Mey (Piperaceae). O estudo fitoquÃmico dos extratos de A. surinamensis, utilizando tÃcnicas clÃssicas de cromatografia em gel de sÃlica, resultou no isolamento de um dÃmero isoflavona inÃdito na literatura, 4â-metoxiisoflavona-(7-O-7ââ)-3âââ,4âââ- metilenodioxiisoflavona (Surinamensina), um triterpeno pentacÃclico comumente conhecido como Lupeol e mais quatro isoflavonas: 5,7-dihidroxi-4â-metoxiisoflavona (biochanina A), 5,4â- dihidroxi-7-metoxiisoflavona (prunetina), 7,3â-dihidroxi-4â-metoxiisoflavona (calicosina) e 5,7,3â-trihidroxi-4â-metoxiisoflavona (pratenseÃna). A determinaÃÃo estrutural dos compostos isolados foram elucidadas por tÃcnicas espectroscÃpicas tais como: espectro de massa, espectro de infravermelho e RessonÃncia MagnÃtica Nuclear de 1H, 13C uni e bidimensionais. A composiÃÃo quÃmica dos Ãleos essenciais das folhas e frutos de Piper divaricatum G. Mey., foram analisadas por CG / EM e CG / DIC. Um total de 24 compostos, representando mais do que 94% da composiÃÃo quÃmica dos Ãleos, foram identificados. Ambos os Ãleos mostraram grande concentraÃÃes de monoterpenos, em especial, o Ãleo das folhas que apresentou 81,1%. Os Ãleos mostraram composiÃÃo quÃmica similares, mas o Ãleo dos frutos pode ser facilmente distinguido do Ãleo das folhas pela exclusiva presenÃa do a-felandrene (4,60%), (E)-muurola- 4(14),5-dieno (9,0%) e do (E)-cariofileno (11,4%). Os maiores constituintes do Ãleo das folhas foram: linalool (23,4%), b-pineno (25,3%) e a-pineno (18,8%), enquanto que os Ãleo frutos apresentaram b-pineno (18.0%), a-pineno (17.6%) e (E)-cariofileno (11.4%), como compostos majoritÃrios. / This work describes the phytochemical investigation of extracts from the branch wood and branch barks of Andira surinamensis (Leguminosae), as well as, the volatile chemical composition of essential oil from leaves and fruits of Piper divaricatum G. Mey (Piperaceae). The phytochemical investigation of A. surinamensis extracts, using classic methods of chromatography on silica gel, yielded a novel isoflavone dimer, 4â-methoxyisoflavone-(7-O- 7ââ)-3âââ,4âââ-methylenedioxyisoflavone (surinamensin), along with the triterpene lupeol and the known isoflavones 5,7-dihydroxy-4\\\'-methoxyisoflavone (biochanin A), 5,4\\\'-dihydroxy-7- methoxyisoflavone (prunetin), 7,3â-dihydroxy-4â-methoxyisoflavone (calycosin) and 5,7,3â- trihydroxy-4â-methoxyisoflavone (pratensein). The structures of all isolated compounds were elucidated by spectroscopic methods, such as MS, IR and particularly 1D and 2D homonuclear and heteronuclear NMR spectroscopy and, comparison with published data for closely related compounds. The chemical composition of the essential oils from leaves and fruits of Piper divaricatum G. Mey., was analyzed by GC/MS and GC-FID. Twenty-four components, representing more than 94.0% of the chemical compositions of the oils, were identified. Both oils showed higher concentrations of monoterpenoids, particularly the oils from leaves (81.1%). The oils showed some compositional similarities but the fruit oil could be easily distinguished from the leaf oil by the exclusive presence of a-phellandrene (4.60%), (E)-muurola-4(14),5-diene (9,0%) and significant content of (E)-caryophyllene (11.4%). The major constituents of the leaf oils were linalool (23.4%), b-pinene (25.3%) and a-pinene (18.8%), while the fruit oils of the fruits contained b-pinene (18.0%) and a-pinene (17.6%) and (E)-caryophyllene (11.4%) as prevalent compounds.

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