{"id":6730,"date":"2018-12-28T10:32:55","date_gmt":"2018-12-28T12:32:55","guid":{"rendered":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/?page_id=6730"},"modified":"2018-12-28T10:34:01","modified_gmt":"2018-12-28T12:34:01","slug":"isac-jose-da-silva-filho-ms","status":"publish","type":"page","link":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/dissertacoesteses\/isac-jose-da-silva-filho-ms\/","title":{"rendered":"Isac Jos\u00e9 da Silva Filho MS"},"content":{"rendered":"

\"faixapos6\"<\/a><\/h2>\n
\n

Isac Jos\u00e9 da Silva Filho<\/h2>\n
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\"\"<\/a><\/p>\n

No dia 19 de abril de 2018, o aluno Isac Jos\u00e9 da Silva Filho, bolsista CNPq, do Programa de P\u00f3s Gradua\u00e7\u00e3o em Biodiversidade Vegetal e Meio Ambiente, defendeu sua disserta\u00e7\u00e3o de mestrado intitulada \u201cEstudo qu\u00edmico bioguiado da macroalga marinha da Ant\u00e1rtica <\/span>Desmarestia menziesii<\/span><\/i> (Phaeophyceae) para isolamento de subst\u00e2ncias com atividades biol\u00f3gicas\u201d.<\/span><\/p>\n

A banca examinadora foi composta pela orientadora Prof. Dra. Luciana Retz de Carvalho (N\u00facleo de Pesquisa em Ficologia do Instituto de Bot\u00e2nica de S\u00e3o Paulo),\u00a0Prof. Dr. Levi Pompermayer Machado (Universidade Estadual Paulista – J\u00falio de Mesquita Filho – UNESP) e\u00a0a Dra. Erika Mattos Stein (Instituto Qu\u00edmica da USP).<\/span><\/p>\n

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Estudo qu\u00edmico bioguiado da macroalga marinha da Ant\u00e1rtica Desmarestia menziesii<\/em> (Phaeophyceae) para isolamento de subst\u00e2ncias com atividades biol\u00f3gicas<\/h3>\n
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ABSTRACT<\/strong><\/h4>\n

The Antarctic region, one of the last continents colonized by man, is a unique region, since it is one of the coldest, windiest and driest places on the planet; also has a very variable photoperiod and high levels of ultraviolet radiation. These extreme conditions determine defense strategies in organisms, which live there. In this region, the terrestrial flora is particularly poor but the marine flora is abundant since there is an high nutrient offer. In this marine environment, algae are present as a primary source for the food chain and forming a large aquatic canopy, where brown macroalgae predominate. In this extreme environment, organisms develop unique mechanisms of survival that may involve the morphology, anatomy, physiology, and production of chemical compounds. Antarctic algae differ from those of other regions mainly due to the high efficiency of their photosynthetic mechanisms, and for the ability to synthesize large amounts of photoprotective substances in addition to antifreeze, anti-herbivory, anti-epiphytic, and anti-incrustation metabolites. These active compounds are target of interest due to their practical applications however, the studies which describe the chemical profile of this ecosystem species of are scarce. Thus, our object of study is the brown macroalgae <\/span>Desmarestia menziessi<\/span><\/i> J.Agardh (Ochrophyta), endemic in the region and component of the large marine canopy. Therefore, our aim was the chemical and biological study of hexane, dichloromethane, ethyl acetate and methanol extracts from this marine macroalga. The specimens were collected on Penguin (62\u00b0 6\u20320\u2033S, 57\u00b056\u20320\u2033W) and Livingston (62\u00ba 38\u201952. 7\u201dS, 60\u00ba 45\u2019 49.8\u201d W) Islands, located in the Antarctic Peninsula, on 1\/8\/2015 and 1\/12\/2016. The biomass collected on Penguin Island was lyophilized, ground (603 g) and <\/span>sequentially\u00a0<\/span>extracted with<\/span> a series of solvents<\/span><\/i>\u00a0of increasing polarity viz., hexane, dichloromethane, ethyl acetate, and methanol, process that gave rise to the extracts <\/span>EH, ED, EAC e EM, respectively. EH was subjected to gas chromatography\/mass spectrometry (GC\/MS); the other extracts were submitted to open column chromatographic fractionation monitored by planar chromatography (PC), <\/span>and\u00a0<\/span>revealed with\u00a0vanillin, p-hydroxybenzaldehyde, ceric sulfate, ferric chloride, ninhydrin, and <\/span><\/i>1,1-diphenyl-2-picrylhydrazyl radical<\/span> (DDPH). One of the fractions of ED was studied by GC\/MS, as well. All extracts and some of its fractions were submitted to anticholinesterase and antifungal biautographic tests. The isolated compounds were identified by Nuclear Magnetic Resonance of Hydrogen and Carbon (NMR <\/span>1<\/span>H and <\/span>13<\/span>C), and MS. The contents of photosynthetic pigments, total soluble proteins and carbohydrate of three regions of tallus (stipe, median and apex) were measured in the material collected from the Livingston Island. Fucosterol, sterol common to brown algae, numerous hydrocarbons and fatty acids, and various contaminants as well were identified in EH. Petroleum hydrocarbons, xenobiotics identified for the first time in Antarctic algae, as well as phthalates and adipate that are plastic waste, were detected in ED. Fractions that presented antioxidant and antifungal activities and whose spectra have a similar appearance to the chromenols, already isolated from this species, were separated from EAC. A compound was isolated as a crystal from EM; its structure was <\/span>established by elucidation of the Infrared, <\/span>1<\/span>H and <\/span>13<\/span>C <\/span>NMR, and MS spectra. This compound, mannitol, is considered reserve material of algae, was isolated in great quantity and for the first time from <\/span>D. menziessi<\/span><\/i>;<\/span> besides, it has <\/span>low freezing point<\/span> and the can storage thermal energy, properties <\/span>which leads one to suppose that it exerts antifreeze activity on algae. Mannitol performs this function on insects and plants from very cold regions. The analyses of the photosynthetic pigment contents showed that they are distributed evenly over the tallus. Correlations directly proportional between chlorophyll <\/span>a<\/b> and chlorophyll <\/span>c <\/b>were observed, as well. In the dosages of total soluble proteins, the apex presented higher content than the stipe and the median, which have similar contents;<\/span> this difference can be attributed to the growth pattern of the species.<\/span> Carbohydrates also showed uniform distribution over the thallus. <\/span>Herein, we present, in addition to contributions on some chemical constituents of<\/span> D. menziessi<\/span><\/i>, an expressive list of pollutants desorbed from the tallus of <\/span>D. menziessi<\/span><\/i>, by the solvents hexane and dichloromethane and a brief discussion on the role of macroalgae as pollution bioindicators.<\/span>
\nKeywords<\/strong>:\u00a0 Extremophile algae; Mannitol; Antifreeze<\/span><\/p>\n

 <\/p>\n

RESUMO<\/strong><\/h4>\n

A regi\u00e3o ant\u00e1rtica, um dos \u00faltimos continentes desbravados pelo homem, \u00e9 uma regi\u00e3o com peculiaridades \u00fanicas, pois \u00e9 um dos locais mais frios, ventosos e secos do planeta; tamb\u00e9m possui fotoper\u00edodo muito vari\u00e1vel e altos n\u00edveis de radia\u00e7\u00e3o ultravioleta. Essas condi\u00e7\u00f5es extremas determinam estrat\u00e9gias de defesa nos organismos que l\u00e1 vivem. Nessa regi\u00e3o, a flora terrestre \u00e9 particularmente pobre, por\u00e9m a flora marinha \u00e9 abundante pois h\u00e1 vultuosa oferta de nutrientes. Nesse ambiente marinho, as algas est\u00e3o presentes como fonte prim\u00e1ria para a cadeia alimentar e tamb\u00e9m formando um grande dossel aqu\u00e1tico, onde predominam as macroalgas pardas. Neste meio extremo, os organismos desenvolvem mecanismos \u00fanicos de sobreviv\u00eancia que podem envolver a morfologia, a anatomia, a fisiologia e a produ\u00e7\u00e3o de compostos qu\u00edmicos. As algas da Ant\u00e1rtica diferem das que habitam outras regi\u00f5es principalmente pela grande efici\u00eancia de seus aparatos fotossint\u00e9ticos e pela capacidade de sintetizar grandes quantidades de subst\u00e2ncias fotoprotetoras, al\u00e9m de metabolitos anticongelantes e com a\u00e7\u00f5es anti-herbivoria, anti-epifitismo e anti-incrusta\u00e7\u00e3o. Esses compostos ativos s\u00e3o alvo de interesse pelas aplica\u00e7\u00f5es pr\u00e1ticas que possuem, por\u00e9m n\u00e3o s\u00e3o numerosos os estudos que descrevem o perfil qu\u00edmico das esp\u00e9cies desse ecossistema. \u00a0Assim, nosso objeto de estudo \u00e9 a macroalga parda end\u00eamica <\/span>Desmarestia menziessi<\/span><\/i> J.Agardh (Ochrophyta), tamb\u00e9m componente do grande dossel marinho. Portanto, o objetivo desse trabalho foi o estudo qu\u00edmico e biol\u00f3gico dos extratos hex\u00e2nico, em diclorometano, em acetato de etila e metan\u00f3lico da macroalga marinha bent\u00f4nica <\/span>Desmarestia menziesii<\/span><\/i>. Os exemplares foram coletados na Ilha Pinguim em 08\/01\/2015 e na Ilha Livingston em 12\/01\/2016, localizadas na Pen\u00ednsula Ant\u00e1rtica. A biomassa coletada na ilha Pinguim foi liofilizada, mo\u00edda e submetida \u00e0 extra\u00e7\u00e3o com a s\u00e9rie de solventes em polaridade crescente hexano, diclorometano, acetato de etila e metanol, dando origem aos extratos EH, ED, EAE e EME, respectivamente. O EH foi submetido \u00e0 cromatografia gasosa\/espectrometria de massas (CG\/EM); os outros extratos foram submetidos a fracionamentos cromatogr\u00e1ficos em coluna aberta, monitoradas por cromatografia planar (CP), em que os derivatizantes foram vanilina, p-hidroxibenzalde\u00eddo, sulfato c\u00e9rico, cloreto f\u00e9rrico, ninidrina e <\/span>1,1-difenil-2-picrilhidrazila<\/span> (DDPH). Uma das fra\u00e7\u00f5es do ED tamb\u00e9m foi submetida a estudos por CG\/EM. Os extratos e algumas de suas fra\u00e7\u00f5es foram submetidas aos ensaios biautogr\u00e1ficos anticolinester\u00e1sico e antif\u00fangico. As subst\u00e2ncias isoladas foram submetidas \u00e0 EM e \u00e0 Espectroscopia de Resson\u00e2ncia Magn\u00e9tica Nuclear de Hidrog\u00eanio e Carbono (RMN <\/span>1<\/span>H e de <\/span>13<\/span>C). J\u00e1 no material coletado da ilha de Livingston foram dosados os teores dos pigmentos fotossint\u00e9ticos, prote\u00ednas sol\u00faveis totais e carboidratos, em tr\u00eas regi\u00f5es do talo: estipe, mediana e \u00e1pice. No EH, foram identificados o fucosterol, esterol comum \u00e0s algas pardas, numerosos hidrocarbonetos e \u00e1cidos graxos comuns a estes organismos, al\u00e9m de diversas subst\u00e2ncias contaminantes. No ED, foram identificados hidrocarbonetos de petr\u00f3leo, xenobi\u00f3ticos identificados pela primeira vez em algas da Ant\u00e1rtica, al\u00e9m de ftalatos e adipato, que s\u00e3o res\u00edduos de pl\u00e1sticos. No EAE foram separadas fra\u00e7\u00f5es que apresentaram atividades antioxidante e antif\u00fangica e cujos espectros t\u00eam fei\u00e7\u00e3o semelhante aos dos cromen\u00f3is, j\u00e1 isolados dessa esp\u00e9cie. O EME forneceu um cristal identificado por espectros de infravermelho (IV), EM e RMN <\/span>1<\/span>H e de <\/span>13<\/span>C como o manitol, considerado material de reserva das algas e isolado pela primeira vez de <\/span>Desmarestia menziessi.<\/span><\/i> A quantidade com que foi encontrado no talo, a propriedade de armazenar energia t\u00e9rmica e o baixo ponto de congelamento levam \u00e0 hip\u00f3tese de que tamb\u00e9m pode exercer atividade anticongelante na alga, fun\u00e7\u00e3o que desempenha em insetos e em plantas de regi\u00f5es muito frias. As an\u00e1lises dos teores de pigmentos fotossintetizantes mostraram que estes est\u00e3o distribu\u00eddos uniformemente ao longo do talo. Tamb\u00e9m foram observadas correla\u00e7\u00f5es diretamente proporcionais entre as clorofila <\/span>a<\/b> e clorofila <\/span>c. <\/b>Quanto \u00e0s dosagens das<\/span> prote\u00ednas sol\u00faveis totais, o teor apresentado pelo \u00e1pice foi menor do que os do estipe e da mediana, que t\u00eam valores semelhantes; essa diferen\u00e7a pode ser atribu\u00edda ao padr\u00e3o de crescimento da esp\u00e9cie (crescimento tricot\u00e1lico). Os carboidratos tamb\u00e9m apresentaram distribui\u00e7\u00e3o uniforme ao longo do talo. No presente trabalho apresentamos, al\u00e9m de contribui\u00e7\u00f5es sobre alguns constituintes qu\u00edmicos de <\/span>D. menziessi,<\/span><\/i> uma expressiva lista de contaminantes dessorvidos do talo da alga pelos solventes hexano e diclorometano e tamb\u00e9m uma breve discuss\u00e3o do papel das macroalgas como bioindicadoras de polui\u00e7\u00e3o. <\/span>
\nPalavras-chave<\/strong>: Algas extrem\u00f3filas; Manitol; Anticongelante<\/span><\/p>\n

<\/h4>\n
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\"pdf_grande\"<\/a>Isac Jos\u00e9 da Silva Filho<\/span><\/a>
\nEstudo qu\u00edmico bioguiado da macroalga marinha da Ant\u00e1rtica Desmarestia menziesii<\/em> (Phaeophyceae) para isolamento de subst\u00e2ncias com atividades biol\u00f3gicas<\/span><\/a><\/p>\n

\n

\u00a0VOLTAR AS DISSERTA\u00c7\u00d5ES E TESES<\/a><\/strong><\/p>\n

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Isac Jos\u00e9 da Silva Filho No dia 19 de abril de 2018, o aluno Isac Jos\u00e9 da Silva Filho, bolsista CNPq, do Programa de P\u00f3s Gradua\u00e7\u00e3o em Biodiversidade Vegetal e Meio Ambiente, defendeu sua disserta\u00e7\u00e3o de mestrado intitulada \u201cEstudo qu\u00edmico bioguiado da macroalga marinha da Ant\u00e1rtica Desmarestia menziesii (Phaeophyceae) para isolamento de subst\u00e2ncias com atividades […]<\/p>\n","protected":false},"author":63,"featured_media":0,"parent":249,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6730"}],"collection":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/users\/63"}],"replies":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/comments?post=6730"}],"version-history":[{"count":2,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6730\/revisions"}],"predecessor-version":[{"id":6742,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6730\/revisions\/6742"}],"up":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/249"}],"wp:attachment":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/media?parent=6730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}