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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

Biotehnološki potencijal filamentoznih sojeva cijanobakterija sa područja Vojvodine / Biotechnological potential of filamentous cyanobacterial strains of the area of Vojvodina

Kovač Dajana 27 September 2017 (has links)
<p>S obzirom&nbsp; da su cijanobakterije (modrozelene alge) identifikovane kao jedna od<br />najperspektivnijih grupa organizama za izolaciju novih i biolo&scaron;ki aktivnih prirodnih<br />produkata, cilj ove teze bio&nbsp; je utvrđivanje biotehnolo&scaron;kog potencijala&nbsp; autohtonih<br />filamentoznih sojeva&nbsp; cijanobakterija izolovanih sa područja Vojvodine koji pripadaju<br />azotofiksirajućim rodovima&nbsp;<em> Nostoc</em>&nbsp; i&nbsp; <em>Anabaena</em>&nbsp; i neazotofiksirajućem rodu&nbsp;&nbsp;&nbsp; <em>Spirulina</em>. Biotehnolo&scaron;ki potencijal testiranih sojeva je određen&nbsp; u smislu produkcije biomase, fikobiliproteinskih pigmenata, masnih kiselina, fenolnih jedinjenja, antioksidanata, antibakterijskih i antikancerogenih agenasa. Dobijeni rezultati su pokazali&nbsp; da su produkcija biomase i sadržaj fikobiliproteinskih pigmenata kod svih testiranih sojeva zavisili od primenjenih uslova kultivacije, pri&nbsp; čemu je&nbsp; kod sojeva roda&nbsp; <em>Spirulina</em> produkcija biomase bila jače stimulisana primenom kontinualnog osvetljenja, a kod azotofiksirajućih sojeva rodova&nbsp;<em> Nostoc&nbsp;</em> i&nbsp;<em> Anabaena</em>&nbsp; organskim izvorima ugljenika (glicerolom i glukozom). Kao soj sa najvećim potencijalom za&nbsp; proizvodnju biomase izdvaja se soj&nbsp; <em>Spirulina&nbsp; S1</em>, a za produkciju fikobiliproteina sojevi&nbsp; <em>Spirulina</em>&nbsp; S1,&nbsp;<em> Nostoc</em> 2S1,&nbsp; <em>Anabaena</em>&nbsp; Č2 i&nbsp; <em>Spirulina</em>&nbsp; S2.&nbsp; Određivanjem sadržaja masnih kiselina GC-FID metodom utvrđeno je da su&nbsp; kod svih sojeva&nbsp; najzastupljenije bile palmitinska, palmitoleinska, oleinska i linolna kiselina, pri čemu su&nbsp; sojevi roda <em>Spirulina</em> produkovali i&nbsp; &gamma;-linolensku kiselinu, dok su svi&nbsp; sojevi rodova&nbsp; <em>Nostoc&nbsp;</em> i&nbsp;<em> Anabaena&nbsp;</em> produkovali&nbsp; -linoleinsku kiselinu.&nbsp; Najzastupljenije fenolne komponente testiranih etanolnih ekstrakata određene HPLC-MS/MS metodom&nbsp; bile su hinska kiselina i katehin, pri čemu je najveći sadržaj fenolnih jedinjenja registrovan kod soja&nbsp; <em>Nostoc</em>&nbsp; 2S7B. Hemijskom karakterizacijom ekstrakata kod testiranih sojeva takođe je utvrđen značaj azotnih uslova kultivacije&nbsp; u cilju povećanja produkcije&nbsp; fenolnih jedinjenja,&nbsp; kao i&nbsp; -linoleinske kiseline. Poređenjem rezultata antioksidantne aktivnosti u kori&scaron;ćenim testovima&nbsp; DPPH&nbsp; i FRAP, kao sojevi sa najvećim&nbsp; antioksidantnim potencijalom izdvajaju se&nbsp; <em>Spirulina</em>&nbsp; S1 i<em> Spirulina</em>&nbsp; S2. Antibakterijska aktivnost metanolnih ekstrakata&nbsp; registrovana je kod sojeva<em> Nostoc</em> 2S7B, <em>Nostoc</em> 2S1, <em>Anabaena</em> Č2, <em>Anabaena</em> Č5, <em>Spirulina</em> S1 i&nbsp;<em> Spirulina</em> S2, koji su ispoljili efekat na Gram-pozitivne i Gram-negativne bakterije, pri čemu su&nbsp; sojevi <em>Anabaena</em>&nbsp; Č2,<em> Nostoc&nbsp;</em> 2S7B&nbsp; i&nbsp; <em>Nostoc</em>&nbsp; 2S1&nbsp; delovali na najvi&scaron;e bakterijskih sojeva.&nbsp; Kod svih testiranih sojeva je primenom MTT testa uočena antikancerogena tj. citotoksična aktivnost dimetil sulfoksidnih (DMSO) ekstrakata prema HepG2 ćelijskoj liniji, među kojima su najveću aktivnost&nbsp; ispoljili sojevi&nbsp;<em> Nostoc</em>&nbsp; LC1B i&nbsp; <em>Nostoc&nbsp; </em>2S7B.&nbsp; Primenom bioeseja&nbsp; <em>Artemia salina, Daphnia magna</em>&nbsp; i&nbsp;&nbsp;<em> Danio rerio&nbsp; </em>konstatovan je mali broj sojeva koji su ispoljili toksičnost na test organizme, dok na ćelijsku liniju&nbsp; RTL-W1&nbsp; testirani sojevi nisu ispoljili citotoksičnost&nbsp;<em> in vitro</em>, &scaron;to sa aspekta potencijalne biotehnolo&scaron;ke primene sojeva ima veliki značaj. Kao najtoksičniji izdvojili su se sojevi<em>&nbsp; Nostoc&nbsp; </em>LC1B&nbsp; i <em>Nostoc </em>S8 koji su ispoljili&nbsp; toksičnost u sva tri bioeseja. Ispitivanjem toksičnosti<em> in vitro</em> u enzimskim esejima konstatovano je da je manji broj sojeva inhibirao aktivnost enzimaprotein fosfataze 1 (PP1) u odnosu na aktivnost enzima&nbsp; acetilholinesteraze&nbsp; (AChE). Primenom Analitičkog hijerarhijskog procesa u grupnom kontekstu, najveću težinu su dobili kriterijumi antikancerogena ativnost, produkcija biomase i sadržaj fikocijanina, navedenim redom. Konačno, u vi&scaron;ekriterijumskom kontekstu najbolje rangiran soj je<br /><em>Spirulina</em> S1, na drugom mestu je soj <em>Spirulina</em> S2, dok je na trećem soj&nbsp;<em> Nostoc&nbsp; </em>LC1B.</p> / <p>Cyanobacteria (blue-green algae) have been identified as one&nbsp; of the most promising groups of organisms for the isolation of new and biologically active natural products, therefore, the aim of this thesis was to determine the biotechnological potential of autochthonous filamentous cyanobacterial strains isolated from&nbsp; Vojvodina region,&nbsp; which belong to the N<sub> 2</sub>-fixing genera&nbsp; <em>Nostoc</em>&nbsp; and&nbsp; Anabaena&nbsp; and non-N<sub>2</sub>-fixing genus&nbsp; <em>Spirulina</em>. Biotechnological potential of tested strains was determined using the production of biomass, phycobiliprotein pigments, fatty acids, phenolic co mpounds, antioxidants, antibacterial and anticancer agents. The obtained results showed that the production of biomass and phycobiliprotein pigments, in all tested strains, depended on the cultivationconditions, whereas biomass production was strongly stimulated by continuous light in<em> Spirulina</em>&nbsp; strains, and by organic carbon sources (glycerol and glucose) in N<sub>2</sub>-fixingstrains. The highest potential for biomass production was shown in&nbsp;<em> Spirulina</em>&nbsp; S1 strain.On the other hand, the highest potential&nbsp; for the production of phycobiliproteins wasshown in strains&nbsp; <em>Spirulina</em>&nbsp; S1,&nbsp; <em>Nostoc&nbsp;</em> 2S1,&nbsp; <em>Anabaena</em> C2 and&nbsp; <em>Spirulina</em>&nbsp; S2. By determination of the content of fatty acids using GC-FID method it was found that in allthe tested strains the most common fatty acids were palmit ic, palmitoleic, oleic andlinoleic acid, whereby the strains of the genus&nbsp; <em>Spirulina</em> produced &gamma;-linolenic acid as well,while all strains of the<em> Nostoc&nbsp;</em> and <em>Anabaena&nbsp;</em> genera produced y-linolenic acid. The most frequent phenolic compounds of tested strains determined by using the HPLC-MS/MSmethod were quinic acid and catechin, with the highest content of phenolic compounds registered in Nostoc&nbsp; strain 2S7B. By chemical characterization of the extracts in the tested strains it was also stated a significance of&nbsp; the nitrogen cultivation conditions in order toincrease the production of phenolic compounds, as well as&nbsp; y-linolenic acid. Comparing the results of the antioxidant activity in the DPPH and FRAP tests, it&nbsp; was shown that strains&nbsp; <em>Spirulina</em>&nbsp; S1 and&nbsp; <em>Spirulina&nbsp;</em> S2 had the highest antioxidant potential. The antibacterial activity of the intracellular methanolic extracts was registered in strains <em>Nostoc&nbsp;</em> 2S7B,&nbsp; <em>Nostoc&nbsp;</em> 2S1,&nbsp; <em>Anabaena</em>&nbsp; C2,&nbsp; <em>Anabaena</em>&nbsp; C5,&nbsp; Spirulina&nbsp; S1 and&nbsp; Spirulina&nbsp; S2, that&nbsp; inhibited the growth of&nbsp; Gram-positive and Gram&nbsp; -negative bacteria. Using MTT test, anti-cancer ie. cytotoxic activity of&nbsp; dimethyl sulfoxide&nbsp; (DMSO) extracts to the HepG2 cell line was detected in all tested strains, however, the highest activity was exhibited in strains <em>Nostoc</em>&nbsp; LC1B and<em> Nostoc</em> 2S7B . In bioassays <em>Artemia salina,&nbsp; Daphnia magna</em>&nbsp; and <em>Danio rerio</em>&nbsp; a small number of strains exhibited toxicity to the test organisms, while in case of cell line RTL-W1 tested strains did not show&nbsp; in vitro&nbsp; cytotoxicity, which is of great importance from the aspect of the potential biotechnological application of thestrains.&nbsp;<em> Nostoc</em>&nbsp; LC1B and&nbsp; <em>Nostoc</em>&nbsp; S8 strains induced toxicity in all three bioassays, and therefore considered as the most toxic strains. By testing&nbsp; in vitro&nbsp; toxicity in enzyme assays, it was found that few strains inhibited the activity of&nbsp; protein phosphatase (PP1) enzyme in relation to&nbsp; acetylcholinesterase&nbsp; enzyme&nbsp; (AChE) activity. Using the Analytical hierarchical process in the group context, the highest weight was given to the criteria of anticancer&nbsp; activity, biomass production, and the phycocyanin content, respectively. Finally, in the multi-criteria context, the best-ranked strain is&nbsp;<em> Spirulina</em>&nbsp; S1,&nbsp; <em>Spirulina&nbsp;</em> strain S2 is on the second place, while <em>Nostoc</em> strain LC1B is the third one.</p>
2

Caracterização e identificação de linhagens de actinomicetos isoladas de amostras de água e sedimento da bacia do rio Tietê. / Characterization of actinomycetes isolated from water and sediment samples from Tietê River Basin.

Ichiwaki, Simone 22 June 2017 (has links)
A bacia do rio Tietê, é a maior região hidrográfica do Estado de São Paulo e possui biodiversidade pouco explorada. Actinomicetos são produtores de moléculas bioativas e são descritas em ambientes aquáticos. O objetivo deste estudo foi caracterizar e identificar actinomicetos isolados da água e sedimento da bacia do rio Tietê. Nove actinomicetos foram isoladas: 6 do gênero Streptomyces e 3 do gênero Micromonospora. Três dos isolados pertencem a novas espécies. Os demais isolados foram identificados como S. bingchenggensis, S. lavendulae, S. humi e S. gancidicus; M. sediminicula e M. tulbaghiae. Todos as linhagens foram capazes de hidrolisar ao menos um dos substratos lignocelulósicos testados. Todos os isolados do gênero Streptomyces apresentaram atividade antifúngica. Com exceção de 2 isolados, todos os isolados apresentaram atividade antibacteriana, inclusive contra bactérias multiresistentes a antibióticos. Os genomas dos isolados foram anotados por RAST e antiSMASH, e apresentaram clusters de PKS do tipo I, II e III, sideróforos, terpenos, NRPS, ectoínas, fenazinas, lantipeptídeos, butirolactonas e bacteriocinas. Todos os isolados deste estudo apresentaram grande potencial biotecnológico, comprovado in silico e in vitro. / The Tietê river basin is the largest hydrographic region of São Paulo and its biodiversity is underexplored. Actinomycetes are known to bioactive molecules, and are described in aquatic environments. The aim of this study was to characterize and identify actinomycetes isolated from water and sediment from the Tietê river basin. Nine strains of actinomycetes were isolated: 6 Streptomyces strains and 3 Micromonospora strains. Three isolates are new species of actinomycetes. The remaining isolates were identified as S. bingchenggensis, S. lavendulae, S. humi and S. gancidicus; M. sediminicula and M. tulbaghiae. All strains could hydrolyse at least one of the lignocellulosic substrates tested. All Streptomyces showed antifungal activity. Except for two strains, all isolates showed antibacterial activity, including against multiresistant bacteria. The genomes of all isolates were annotated by RAST and antiSMASH and showed clusters of: type I, II and III PKS, siderophores, terpenes, NRPS, ectoins, phenazines, lantipeptides, butyrolactones and bacteriocins. All isolates in this study showed a high biotechnological potential, proved by in silico and in vitro methods.
3

Advances in Flavonoid Glycosyltransferase Research: Integrating Recent Findings With Long-Term Citrus Studies

McIntosh, Cecilia A., Owens, Daniel K. 01 December 2016 (has links)
Flavonoid glycosides are required for a number of crucial roles in planta and have the potential for development in a variety of agricultural, medicinal, and biotechnological applications. A number of recent advancements have been made in characterizing glycosyltransferases, the enzymes that are responsible for the synthesis of these important molecules. In this review, glycosyltransferases are considered with regard to biochemical properties, expression patterns, levels of enzyme activity during development, and structure/function relationships. This is presented with historical context to highlight critical findings, particularly with regard to the innovative work that has come from research on citrus species. The plant glycosyltransferase crystal structures that have been solved over the past decade, either alone or in complex with sugar donor and/or acceptor molecules, are discussed. The application of results from these structures to inform current structure/function work as well as implications and goals for future crystallography and tertiary modeling studies are considered. A thorough understanding of the properties of glycosyltransferases will be a critical step in any future biotechnological application of these enzymes in areas such as crop improvement and custom design of enzymes to produce desired compounds for nutritional and/or medicinal usage.
4

Otimização da produção e purificação de compostos antimicrobianos de leveduras para desenvolvimento de um novo agente antifúngico / Optimization of production and purification of antimicrobial compounds from yeast for the development of a new antifungal agent

Senter, Luciana January 2010 (has links)
Infecções fúngicas em humanos vem aumentando nos últimos anos e acometem principalmente pacientes imunocomprometidos, portadores do vírus HIV, transplantados ou com câncer. Os antifúngicos empregados no tratamento pertencem a poucos grupos de fármacos e o aparecimento de resistência antifúngica em muitos patógenos leva à necessidade de desenvolvimento de novos agentes antifúngicos. As cepas Trichosporon japonicum QU139 e Candida catenulata LV102 apresentam atividade killer sobre diversas leveduras patogênicas, apresentando bom potencial para desenvolvimento de novos agentes antimicrobianos. O objetivo do trabalho foi a otimização das condições para produção e detecção dos compostos antimicrobianos, para seu futuro uso terapêutico, e sua purificação. O efeito killer da cepa T. japonicum QU139 foi avaliado pelo método dos poços contra células sensíveis de Cryptococcus gattii C20 nos meios GYP, YM e Queijo em diferentes pH e temperaturas. A máxima atividade killer foi encontrada no meio GYP, pH 4,5 à 25°C após 24 horas de incubação para T.japonicum QU139 e C. catenulata LV102. Não foi possível isolar o composto antimicrobiano produzido pela levedura T.japonicum QU139 pelos métodos de isolamento de proteína/glicoproteína, corroborando a hipótese de que a toxina seja um glicolipídeo. / Human fungal infections have increased in the last years and affect mainly immunocompromised patients, carriers of HIV vírus, transplanted or with cancer. The antifungal agents used in treatment belong to a few groups of drugs and the increase of antifungal resistance in many pathogens leads to the necessity of developing new antifungal agents. Strains Trichosporon japonicum QU139 and Candida catenulata LV102 showed killer activity against several pathogenic yeasts, having a good potential for the development of new antimicrobial agents. The objective of the work was the optimization of conditions for production and detection of the antimicrobial compounds, aiming their future terapeutic use, and their purification. The killer effect of T. japonicum QU139 strain was evaluated by the well method against sensitive cells of Cryptococcus gattii C20 in media GYP, YM and Cheese in different pH and temperatures. The maximum killer activity was found in media GYP, pH 4.5, 25°C after 24 hours of incubation for T.japonicum QU139 and C. catenulata LV102. The isolation of the antimicrobial compound produced by the yeast T.japonicum QU139 was not possible by the methods for isolation of proteins/glicoproteins, corroborating the hypothesis that the toxin is a glycolipid.
5

Otimização da produção e purificação de compostos antimicrobianos de leveduras para desenvolvimento de um novo agente antifúngico / Optimization of production and purification of antimicrobial compounds from yeast for the development of a new antifungal agent

Senter, Luciana January 2010 (has links)
Infecções fúngicas em humanos vem aumentando nos últimos anos e acometem principalmente pacientes imunocomprometidos, portadores do vírus HIV, transplantados ou com câncer. Os antifúngicos empregados no tratamento pertencem a poucos grupos de fármacos e o aparecimento de resistência antifúngica em muitos patógenos leva à necessidade de desenvolvimento de novos agentes antifúngicos. As cepas Trichosporon japonicum QU139 e Candida catenulata LV102 apresentam atividade killer sobre diversas leveduras patogênicas, apresentando bom potencial para desenvolvimento de novos agentes antimicrobianos. O objetivo do trabalho foi a otimização das condições para produção e detecção dos compostos antimicrobianos, para seu futuro uso terapêutico, e sua purificação. O efeito killer da cepa T. japonicum QU139 foi avaliado pelo método dos poços contra células sensíveis de Cryptococcus gattii C20 nos meios GYP, YM e Queijo em diferentes pH e temperaturas. A máxima atividade killer foi encontrada no meio GYP, pH 4,5 à 25°C após 24 horas de incubação para T.japonicum QU139 e C. catenulata LV102. Não foi possível isolar o composto antimicrobiano produzido pela levedura T.japonicum QU139 pelos métodos de isolamento de proteína/glicoproteína, corroborando a hipótese de que a toxina seja um glicolipídeo. / Human fungal infections have increased in the last years and affect mainly immunocompromised patients, carriers of HIV vírus, transplanted or with cancer. The antifungal agents used in treatment belong to a few groups of drugs and the increase of antifungal resistance in many pathogens leads to the necessity of developing new antifungal agents. Strains Trichosporon japonicum QU139 and Candida catenulata LV102 showed killer activity against several pathogenic yeasts, having a good potential for the development of new antimicrobial agents. The objective of the work was the optimization of conditions for production and detection of the antimicrobial compounds, aiming their future terapeutic use, and their purification. The killer effect of T. japonicum QU139 strain was evaluated by the well method against sensitive cells of Cryptococcus gattii C20 in media GYP, YM and Cheese in different pH and temperatures. The maximum killer activity was found in media GYP, pH 4.5, 25°C after 24 hours of incubation for T.japonicum QU139 and C. catenulata LV102. The isolation of the antimicrobial compound produced by the yeast T.japonicum QU139 was not possible by the methods for isolation of proteins/glicoproteins, corroborating the hypothesis that the toxin is a glycolipid.
6

Otimização da produção e purificação de compostos antimicrobianos de leveduras para desenvolvimento de um novo agente antifúngico / Optimization of production and purification of antimicrobial compounds from yeast for the development of a new antifungal agent

Senter, Luciana January 2010 (has links)
Infecções fúngicas em humanos vem aumentando nos últimos anos e acometem principalmente pacientes imunocomprometidos, portadores do vírus HIV, transplantados ou com câncer. Os antifúngicos empregados no tratamento pertencem a poucos grupos de fármacos e o aparecimento de resistência antifúngica em muitos patógenos leva à necessidade de desenvolvimento de novos agentes antifúngicos. As cepas Trichosporon japonicum QU139 e Candida catenulata LV102 apresentam atividade killer sobre diversas leveduras patogênicas, apresentando bom potencial para desenvolvimento de novos agentes antimicrobianos. O objetivo do trabalho foi a otimização das condições para produção e detecção dos compostos antimicrobianos, para seu futuro uso terapêutico, e sua purificação. O efeito killer da cepa T. japonicum QU139 foi avaliado pelo método dos poços contra células sensíveis de Cryptococcus gattii C20 nos meios GYP, YM e Queijo em diferentes pH e temperaturas. A máxima atividade killer foi encontrada no meio GYP, pH 4,5 à 25°C após 24 horas de incubação para T.japonicum QU139 e C. catenulata LV102. Não foi possível isolar o composto antimicrobiano produzido pela levedura T.japonicum QU139 pelos métodos de isolamento de proteína/glicoproteína, corroborando a hipótese de que a toxina seja um glicolipídeo. / Human fungal infections have increased in the last years and affect mainly immunocompromised patients, carriers of HIV vírus, transplanted or with cancer. The antifungal agents used in treatment belong to a few groups of drugs and the increase of antifungal resistance in many pathogens leads to the necessity of developing new antifungal agents. Strains Trichosporon japonicum QU139 and Candida catenulata LV102 showed killer activity against several pathogenic yeasts, having a good potential for the development of new antimicrobial agents. The objective of the work was the optimization of conditions for production and detection of the antimicrobial compounds, aiming their future terapeutic use, and their purification. The killer effect of T. japonicum QU139 strain was evaluated by the well method against sensitive cells of Cryptococcus gattii C20 in media GYP, YM and Cheese in different pH and temperatures. The maximum killer activity was found in media GYP, pH 4.5, 25°C after 24 hours of incubation for T.japonicum QU139 and C. catenulata LV102. The isolation of the antimicrobial compound produced by the yeast T.japonicum QU139 was not possible by the methods for isolation of proteins/glicoproteins, corroborating the hypothesis that the toxin is a glycolipid.
7

Potencial biotecnológico de bactérias e leveduras isoladas da casca do Coco-verde (Cocos Nucifera) em fermentação / Biotechnological potential of bactéria and yeasts isolated from fermenting Green coconut Shell (Cocos Nucifera)

Alves, Maurício Marcelino de Sousa 11 May 2017 (has links)
The culture of coconut is economically relevant to Brazil but suffers with the breeding of pests that target coconut trees and bring on economic losses. One of the pests responsible for such is the palm weevil R. palmarum L., which is attracted to the infestation site by the odor released from the fermentation of plant tissues. This is particularly problematic when the crop, processing and disposal sites are in close location, for the residue discarded (i.e. green coconut shell) undergoes the action of microorganisms that produce volatile compounds and attract the pest to the crop site. This research had as its objective the isolation and characterization of bacteria and yeasts responsible for the fermentation of green coconut shell and production of volatile compounds that are attractive to the palm weevil. For such, green coconut shells were exposed to the local environment for the development of the fermentative processes, having the emitted volatiles analyzed on five different days of fermentation (0, 3, 5, 7, and 10 days). Thirty different compounds belonging to different chemical classes were detected for all of the analyzed days, being alcohols, ketones, aldehydes and hydrocarbons the most frequently found. Isolation procedures were performed immediately after the opening of the coconuts and at the sixth day of fermentation. After purification, thirty eight strains (15 bacteria and 23 yeasts) were obtained and characterized. The characterization of the strains was based on the determination of orphological, physiological and biochemical characteristics and the evaluation of the biotechnological potential. The isolated strains presented variable biochemical profile, although each of them displayed at least one positive result for the tested enzymes. Although bacterial isolates were halotolerant, yeast strains were more. Among the bacterial strains, the isolate A5 stood out for displaying activity for all of the tested enzymes except for laccase besides being capable of degrading filter paper in liquid media. The isolate E4 stood out among the yeast strains for presenting activity for five of the tested enzymes (amylases, pectinases, xylanases, proteases and lipases/esterases) besides displaying tolerance up to 10% NaCl. Therefore each strain presented different biotechnological potential, some of them being potential candidates for the production of volatile compounds by fermentation of the green coconut shell. A few strains were identified to the genus level by the technique of MILDI-TOF, resulting in identification of three bacterial (Bacillus, Pantoea e Arthrobacter) e three yeasts (Pichia, Cryptococcus e Rhodotorula) genera. The production of volatile compound by four selected strains was investigated and resulted on the detection of over 100 different compounds, among which are included ketones, carboxylic acids, pyrazines, esters, hydrocarbons, aldehydes, terpenes and terpenoids. A few of the detected volatiles had been previously reported as attractive to R. palmarum confirming that there is a relationship between the metabolic activity of the isolated microorganisms and production of volatiles attractive to this pest. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A cultura do coqueiro é economicamente importante para o Brasil, mas sofre com a proliferação de pragas que almejam os coqueiros e causam prejuízo econômico. Uma das pragas é a broca-do-olho-do-coqueiro, R. palmarum L., que é atraído para os locais de infestação pelo odor de fermentação de tecidos vegetais. Isto é particularmente problemático quando os locais de plantação, de processamento dos frutos e de descarte de resíduos são próximos, pois o resíduo gerado (casca do coco-verde, por exemplo) sofre ação de microrganismos que produzem compostos voláteis e atraem o inseto para a plantação. Esta pesquisa teve como objetivo o isolamento e a caracterização de bactérias e leveduras responsáveis pela fermentação da casca do coco-verde com concomitante produção de compostos voláteis atrativos para a broca-do-olho-do-coqueiro. Para tanto, cascas de coco-verde recém-abertas foram expostas ao ambiente para desenvolvimento de processo fermentativo, sendo a emissão de voláteis analisada em cinco dias diferentes de fermentação (dias 0, 3, 5, 7 e 10). Trinta compostos de classes químicas variadas foram detectados para os diferentes dias de fermentação, sendo encontrados álcoois, cetonas, aldeídos e hidrocarbonetos com maior frequência. Isolamentos foram realizados após abertura dos cocos e no sexto dia de fermentação. Após purificação, trinta e oito linhagens (15 bactérias e 23 leveduras) foram obtidas e caracterizadas. A caracterização teve como base a determinação de características morfológicas, fisiológicas e bioquímicas e a avaliação do potencial biotecnológico. As linhagens isoladas exibiram perfil bioquímico variado, sendo que todos apresentaram pelo menos um resultado positivo para alguma das enzimas extracelulares testadas. Embora as bactérias tenham sido halotolerantes, as leveduras foram mais. Dentre as bactérias isoladas, o isolado A5 se destacou por apresentar atividade para todas as enzimas testadas exceto lacases, além de demostrar capacidade de degradar papel de filtro em meio líquido. O isolado E4 se destacou entre as leveduras por apresentar atividade para cinco enzimas (amilases, pectinases, xilanases, proteases e lipases/esterases), além de apresentar tolerância a 10% de NaCl. Portanto, cada linhagem isolada apresentou potencial biotecnológico variável, algumas sendo potenciais candidatas para a produção de voláteis pela fermentação da casca do coco-verde. Alguns isolados foram identificados a nível de gênero pela técnica de MALDI-TOF, resultando na identificação de três gêneros de bactérias (Bacillus, Pantoea e Arthrobacter) e três de leveduras (Pichia, Cryptococcus e Rhodotorula). A produção de voláteis por culturas puras de quatro isolados selecionados foi estudada, sendo encontrados mais de 100 compostos diferentes, principalmente cetonas, ácidos carboxílicos, pirazinas, ésteres, hidrocarbonetos, aldeídos, terpenos e terpenóides. Alguns dos voláteis detectados já haviam sido relatados como atrativos para o R. palmarum., confirmando que existe relação entre a atividade metabólica dos microrganismos isolados e produção de voláteis atrativos para esta praga.
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Studium kultivovatelné anaerobní bakteriální komunity žijící v symbióze s kůrovci; její izolace, taxonomie a biotechnologický poteciál.� / Study of culturable anaerobic bacterial communities living in symbiosis with bark beetles; its isolation, taxonomy and biotechnical potential.

Fabryová, Anna January 2016 (has links)
Microbial enzymes implicated in plant cell hydrolysis may have several potential aplications such as biomass degradation biocatalysts or with biofuel production. Bark beetles establish symbiosis with several microbial strains which play different roles benifitting the beetle, as the production of hydrolytic enzymes to degrade the ingested wood, the protection against mirobial antagonist or the detoxification of the environment. Fungal symbionts have been traditionally the best studied, but several recent research with bacterial symbionts of several bark beetle species show that bacterial also display important functions for the host. In this study, the bacterial communities of the bark beetle species Cryphalus piceae and Pithophtorus pithophtorus, collected in the Czech Republic from pine and fir trees, respectively, were isolated and 55 out of 89 samples were identified by 16S rRNA gene amplification and sequencing. Members of the genera Erwinia, Pantoea, Curtobacterium, Yersinia, Pseudomonas and Staphylococcus were detected. The isolates were object of study for their possible biotechnological potential in (ligno)cellulose materials degradation by screening several enzymes implicated in plant cell hydrolysis, as cellulases, xylanases, amylases, laccases, as well as their capability for colorant...

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