Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-12-12T19:35:46Z No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-12-14T18:31:11Z (GMT) No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) / Made available in DSpace on 2017-12-14T18:31:11Z (GMT). No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) Previous issue date: 2017-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A corros?o microbiologicamente induzida (CMI) atinge todos os setores de produ??o da ind?stria de petr?leo e g?s e demanda expressivos gastos e investimentos para preven??o e controle. O objetivo dessa tese foi avaliar as atividades biocida e antibiofouling de metab?litos de microrganismos endof?ticos de Lippia gracilis Schauer como tamb?m do ?leo essencial (puro e em sistema microemulsionado) dessa esp?cie sobre biofilmes microbianos em a?o carbono 1020 AISI. Os experimentos utilizaram cupons de a?o carbono 1020 AISI dispostos em Erlenmyers e em sistema din?mico para a obten??o dos biofilmes. A avalia??o biocida dos metab?litos deu-se pela quantifica??o microbiana pelas t?cnicas de absorb?ncia, do n?mero mais prov?vel (NMP), antes e ap?s os tratamentos. Os tratamentos consistiram em: 0, 100, 150 e 200 ?g/L de cada metab?lito sobre biofilmes nos tempos de contato zero, duas, tr?s e quatro semanas, com tr?s repeti??es por tratamentos. A a??o antibiofouling foi realizada pelo contato dos metab?litos na maior concentra??o (200 ?g/L) com os biocupons antes da obten??o dos biofilmes. A a??o antimicrobiana do ?leo essencial de L. gracilis Schauer na forma pura, e em sistema microemulsionado, foi avaliada pela quantifica??o de bact?rias redutoras de sulfato (BRS), oxidantes de ferro (BOF), fungos, bact?rias aer?bias e anaer?bias totais, pelas t?cnicas de NMP, plaqueamento pour plate, espectrofotometria de massa (EM) e an?lise de micrografias realizadas antes e ap?s os tratamentos. A atividade anticorrosiva foi avaliada por imped?ncia e polariza??o eletroqu?micas, testes gravim?tricos (perda de massa e quantifica??o de pites) bem como pela obten??o de micrografias da superf?cie do a?o carbono. Amostras de L. gracilis Schauer foram coletadas no munic?pio de Mossor? - RN e foram isolados fungos e bact?rias das ra?zes e folhas. Uma nova esp?cie de fungo foi descoberta e identificada como Achaetomium lippae. Foram obtidos tr?s metab?litos: dois de fungos e um de bact?ria. Os resultados mostraram que houve diferen?a da atividade biocida e antibiofouling entre os metab?litos de endof?ticos de L. gracilis Schauer avaliados, sendo LGS-Rb1 o mais eficiente na maioria tipos microbianos testados, evitando a forma??o de biofouling e reduzindo a taxa de crescimento microbiano na maior concentra??o avaliada. Os ensaios eletroqu?micos e gravim?tricos mostraram que para todos os metab?litos houve varia??o na atividade anticorrosiva. O ?leo essencial de L. gracilis Schauer avaliado in natura inibiu significativamente o crescimento in vitro de C. bifermentans e de fungos em biofilme, reduzindo sua taxa de crescimento a zero a partir de 20 ?g.L-1. Os ensaios eletroqu?micos e gravim?tricos mostraram que a concentra??o de 60 ?g.L-1 do ?leo essencial foi eficiente na redu??o da corros?o. Nos ensaios usando o sistema microemulsionado o ?leo essencial inibiu eficientemente o crescimento de BRS, BOF e fungos ap?s 16 dias de contato e teve atividade antibiofouling ap?s 96 horas de contato com os biocupons de a?o carbono AISI 1020. Dessa forma os metab?litos de endof?ticos de L. gracilis Schauer bem como seu ?leo essencial mostram-se como novas alternativas de biocidas naturais eficientes no controle da corros?o microbiologicamente induzida. / The corrosion microbiologically induced (CMI) reaches all the sectors of production of the industry in Petroleum oil and Gas and demands expressive expensive and investments for prevention and control. The goal of this thesis was to evaluate the biocide and antibiofouling activities of secondary metabolites obtained from endophytic microorganisms of Lippia gracilis Schauer as well of the essential oil (pure and in microemulsified system) from this species on microbial biofilms in 1020 AISI carbono steel. The experiments for biocide activity used 1020 AISI carbon steel plate arranged in Erlenmyers and dynamic system with forced circulation for obtaining of the total biofilms from water produced by oil. The assessment for biocide of the metabolites from endophytic of L. gracilis Schauer resulted of the quantification of these species of bacteria in the quantification techniques by absorbance in more probable numbers (MPN), before and after the treatments, had been identified by gas chromatography coupled the spectrophotometry in mass (CG-MS) and magnetic resonance imaging (MRI) just those who demonstrated activities. The treatments consisted in evaluating the concentrations 0, 100, 150 and 200 ?g/L in each metabolites on biofilms in times contact to zero, two, three and four weeks, with three repetition by treatments. The antibiofouling action was made in the contact of the metabolites in the highest concentration (200 ?g/L) with the bioplates before being inserted into the dynamic system. The antimicrobial action of the essential oil L. gracilis Schauer in the pure form and in a microemulsified system was evaluated by the quantification bacteria reducer of sulphate (BRS), oxidant of iron (BOI), fungi, aerobic bacteria and total anaerobes by the techniques of dilution, platingpourplate, spectrophotometry in mass (MS) and micrographs analysis made before and after the treatments. The anticorrosive activity of all bioproducts was evaluated by electrochemical impedance and polarization, gravimetric examinations of mass loss and quantification of pites, as well in the obtaining of micrographs of the carbon steel`s surface. Samples of L. gracilis Schauer were collected in the city of Mossor? - RN and were isolated fungi and bacteria from the roots and leaves. A new type of fungus was discovered and identified as Achaetomium lippae. Three metabolites were obtained: two fungi (LGS-Lf1 and LGS-Lf2, being "LGS" for L. gracilis Schauer, "L": leaf, ?f?: fungus and "R" for root) and one of bacteria (LGS-Rb1, being "LGS" for L. gracilis Schauer, "R": root and "b": bacterium). The results showed that there was a difference in the biocide activity and antibiofouling between the metabolites from endophytic of L. gracilis Schauer assessed, being just the LGS-Lf1 being efficient over all the microorganisms tested, avoiding the formation of biofouling on the surface of the material and reducing the rate of microbial growth at zero after 96 hours of contact at the highest concentration evaluated. The electrochemical and gravimetric tests displayed that for all the metabolites occured change in the anticorrosive activity. The L. gracilis Schauer essential oil evaluated in the pure form inhibited significally the growth in vito of C. bifermentans and of fungi in biofilm, reducing their growth rate to zero as from 20 ?g.L-1. The electrochemical and gravimetric tests showed that the concentration of 60 ?g.L-1 of the essential oil was efficient in the reduction of corrosion. In the tests, using the microemulsified system, the essential oil inhibited the growth of BRS, BOF and fungi 16 days later in contact and had antibiofouling activity after 96 hours in contact with the AISI 1020 bioplates of carbon steel. Therefore, the metabolites from endophytic of L. gracilis Schauer as well its essential oil are shown as new alternatives of natural biocides efficient in the control of the corrosion microbiologically induced.