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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.
21

Estudo bioquímico de β-glucosidases de Malbranchea pulchella e aplicações na hidrólise de resíduos agroindustriais e de antocianinas / Biochemical study of ?-glucosidases from Malbranchea pulchella and applications in agroindustrial residues and anthocyanins hydrolysis

Monteiro, Lummy Maria Oliveira 01 August 2016 (has links)
?-glucosidases são enzimas que catalisam a hidrólise de ligações glucosídicas ?-1,4, ?-1,3 e ?-1,6 a partir da extremidade não redutora de oligossacarídeos de cadeias pequenas, alquil e aril ?-D-glucosídeos e dissacarídeos. Além de serem enzimas chave do complexo celulolítico, apresentam funções importantes como o melhoramento de aromas de vinhos e a hidrólise de antocianinas. Malbranchea pulchella usualmente é encontrado em fragmentos vegetais em decomposição ou material rico em celulose, podendo ser considerado promissor à produção de enzimas de interesse biotecnológico. Neste contexto, o objetivo desse projeto foi a caracterização funcional de uma ?-glucosidase de M. pulchella e sua aplicação na hidrólise de resíduos agroindustriais e de antocianinas. Uma BGL da família GH3 foi purificada com um fator de purificação 6,32 e recuperação de aproximadamente 35 %. A sua massa molecular aproximado foi de 100 kDa, e o Km, Vmáx e Kcat foram calculadas em 0,33 mM, 13,67 U/mg, 26,5 s-1 respectivamente. O dicroísmo circular revelou uma estrutura composta por aproximadamente 25% de ?-hélices e 20% de ?-folhas. A BGL apresentou pH e temperatura ótimos igual a 6,0 e 50 °C; e foi estável a 40 °C e apresentou boa estabilidade nos pH 5,0 a 8,0, por 24 horas. Nenhum dos sais de íons metálicos ativou a enzima e apenas o HgCl2 inibiu a atividade em 90%. A enzima não apresentou inibição em presença de glucose (0,1-1M) por até 24 horas. Além disso, a GH3 mostrou-se glicosilada e a proporção de açúcar corresponde a 15% massa da enzima. O efeito da celobiose (C) e do bagaço de cana-de-açúcar in natura (BCAN) na produção das BGLs foram avaliados em um DCCR, que indicou um modelo reduzido com influência das duas variáveis. A melhor condição de cultivo para a produção de BGLs foi 0,6% de C (p/v) e 4% de BCAN (p/v). Por meio de um planejamento de mistura, os resíduos BCAN, a casca de soja moída (CS) e o bagaço de cevada (BCev), foram avaliados quanto ao potencial de hidrólise a partir das enzimas presentes no extrato enzimático, resultando no maior potencial de hidrólise sobre o BCev, com a produção de aproximadamente 2 mg/mL de açúcares redutores em 48 horas. As BGLs presentes no extrato enzimático otimizado foram imobilizadas em suporte MANAE-agarose, Concanavalina A-Sepharose e BrCN-Sepharose. Os derivados BGL-MANAE e BGL-ConA foram ativados aproximadamente 10 e 3 vezes, respectivamente. BGL-MANAE e BGL-ConA foram mais estáveis que o controle BGLBrCN em todos os pH testados em 24 horas e, além disso, BGL-ConA permaneceu com 100% de sua atividade em temperaturas de 40 °C, 50 °C e 60 °C, já o BGL-MANAE mostrou-se estável a 40 °C permanecendo com 83% de sua atividade, ambos em 24 horas. BGL-MANAE e BGL-ConA apresentaram menor efeito inibitório em presença de diferentes concentrações de glucose e etanol quando comparados ao BGL-BrCN, e esses resultados indicaram que a imobilização de alguma forma colaborou para uma maior estabilidade ao pH e à temperatura, bem como ao aumento da tolerância por glucose e etanol. Os derivados puderam ser reutilizados por até 20 vezes e quando avaliados quanto à capacidade de clarificar vinhos e sucos de uva (hidrólise de antocianinas), BGL-MANAE clarificou 52% o vinho, 71% o vinho diluído, 77% o suco de uva e 56% o suco de uva diluído, e BGL-ConA em contrapartida clarificou 41% o vinho, 46% o vinho diluído, 63% o suco de uva e 23% o suco de uva diluído. BGL-MANAE foi mais eficiente que BGL-ConA na clarificação de vinhos e sucos de uva podendo ser considerado um biocatalisador promissor na hidrólise de antocianinas e, consequentemente, para a produção de vinhos brancos e rose a partir de diferentes variedades de uvas. Este trabalho pelo que sabemos, é o primeiro a usar BGLs imobilizadas com aplicação na clarificação de sucos de uva e vinhos, podendo ser considerado um trabalho inovador, e de grande importância para a indústria de alimentos e bebidas. / ?-glucosidases are enzymes that catalyze the hydrolysis of ?-1,4, ?-1,3 and ?-1,6 glucosidic linkages, from the non-reducing end of short chain oligosaccharides, alkyl and aryl ?-D-glucosides and disaccharides. Besides being complex key cellulolytic enzymes, they have important functions such as the improvement of wine flavors and anthocyanins hydrolysis. Malbranchea pulchella is usually found in decaying plant debris or in material rich in cellulose, for this reason it can be considered promising for the production of enzymes of biotechnological interest. In this context, the aim of this project was the functional characterization of a ?-glucosidase from M. pulchella and its application in the organic residues and anthocyanins hydrolysis. A BGL GH3 family produced by M. pulchella was purified with a purification factor and recovery of about 6.32 and 35 times. Its approximate molecular mass was 100 kDa, and Km, Vmax and kcat were 0.33 mM, 13.67 U/mg, 26.5 s-1, respectively. The circular dichroism revealed a structure composed of approximately 25% of ?-helix and 20% of ?-sheets. BGL presented optimum pH and temperature at 6.0 and 50 °C; and it was stable at 40 °C. It also showed good stability at pH 5.0 to 8.0, for 24 hours. None of the metal ions salts activated the enzyme and HgCl2 inhibited the activity by 90%. The enzyme showed no inhibition in the presence of glucose (0,1-1M) for 24 hours. Furthermore, it is glycosylated and the sugar proportion correspondsto 15% of the enzyme mass. The effect of cellobiose (C) and sugarcane bagasse in natura (BCAN) in the production of BGLs were evaluated in a CCRD, which indicated a reduced model of influence of the two variables. The best culture condition for BGLs production was 0.6% of C (w/v) and 4% (w/v) of BCAN. Through a mixture design, using the BCAN, ground soybean hulls (CS) and barley bagasse (BCev) were used to evaluate the potential of hydrolysis of these residues in the presence of enzymes present in the enzymatic extract, resulting in a greater efficiency of (BCev) hydrolysis, producing approximately 2 mg/mL of reducing sugars in 48 hours. The BGLs present in the optimized enzyme extract were also used in the immobilization on ionic support MANAE-agarose and affinity support Concanavalin A-Sepharose (ConA-Sepharose). The BGL-MANAE and BGL-ConA derivatives were activated approximately 10 and 3 times, respectively. BGL-MANAE and BGL-ConA were more stable than BGL-BrCN control in all pH tested within 24 hours. In addition, BGL-ConA remained 100% of its activity at 40 °C, 50 °C and 60 °C , and BGL-MANAE was stable at 40 °C and remained 83% of its activity, both in 24 hours. BGL-MANAE and BGL-ConA showed lower inhibitory effect in the presence of different glucose and ethanol concentrations when compared to BGL-BrCN and these results indicate that the immobilization, somehow, cooperated to a greater pH and temperature stability, as well as to increased tolerance by glucose and ethanol. The derivatives could be reused up to 20 times and when they were tested for their capacity to clarify wine and grape juice (anthocyanins hydrolysis), BGL-MANAE clarified 52% wine, 71% diluted wine, 77% grape juice and 56% diluted grape juice. On the other hand, BGL-ConA clarified 41% wine, 46% diluted wine, 63% grape juice and 23% diluted grape juice. BGL-MANAE was more efficient than BGL-ConA in clarifying wines and grape juices and it may be considered a promising biocatalyst in the anthocyanins hydrolysis, and consequently in the production of white and rose wines from different varieties of grapes. This work as we know, is the first to use immobilized BGLs applied in the clarification of grape juice and wine, for this reason, it can be considered an innovative work, and of great importance to the food and beverage industry
22

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>
23

Estudo bioquímico de &#946;-glucosidases de Malbranchea pulchella e aplicações na hidrólise de resíduos agroindustriais e de antocianinas / Biochemical study of ?-glucosidases from Malbranchea pulchella and applications in agroindustrial residues and anthocyanins hydrolysis

Lummy Maria Oliveira Monteiro 01 August 2016 (has links)
?-glucosidases são enzimas que catalisam a hidrólise de ligações glucosídicas ?-1,4, ?-1,3 e ?-1,6 a partir da extremidade não redutora de oligossacarídeos de cadeias pequenas, alquil e aril ?-D-glucosídeos e dissacarídeos. Além de serem enzimas chave do complexo celulolítico, apresentam funções importantes como o melhoramento de aromas de vinhos e a hidrólise de antocianinas. Malbranchea pulchella usualmente é encontrado em fragmentos vegetais em decomposição ou material rico em celulose, podendo ser considerado promissor à produção de enzimas de interesse biotecnológico. Neste contexto, o objetivo desse projeto foi a caracterização funcional de uma ?-glucosidase de M. pulchella e sua aplicação na hidrólise de resíduos agroindustriais e de antocianinas. Uma BGL da família GH3 foi purificada com um fator de purificação 6,32 e recuperação de aproximadamente 35 %. A sua massa molecular aproximado foi de 100 kDa, e o Km, Vmáx e Kcat foram calculadas em 0,33 mM, 13,67 U/mg, 26,5 s-1 respectivamente. O dicroísmo circular revelou uma estrutura composta por aproximadamente 25% de ?-hélices e 20% de ?-folhas. A BGL apresentou pH e temperatura ótimos igual a 6,0 e 50 °C; e foi estável a 40 °C e apresentou boa estabilidade nos pH 5,0 a 8,0, por 24 horas. Nenhum dos sais de íons metálicos ativou a enzima e apenas o HgCl2 inibiu a atividade em 90%. A enzima não apresentou inibição em presença de glucose (0,1-1M) por até 24 horas. Além disso, a GH3 mostrou-se glicosilada e a proporção de açúcar corresponde a 15% massa da enzima. O efeito da celobiose (C) e do bagaço de cana-de-açúcar in natura (BCAN) na produção das BGLs foram avaliados em um DCCR, que indicou um modelo reduzido com influência das duas variáveis. A melhor condição de cultivo para a produção de BGLs foi 0,6% de C (p/v) e 4% de BCAN (p/v). Por meio de um planejamento de mistura, os resíduos BCAN, a casca de soja moída (CS) e o bagaço de cevada (BCev), foram avaliados quanto ao potencial de hidrólise a partir das enzimas presentes no extrato enzimático, resultando no maior potencial de hidrólise sobre o BCev, com a produção de aproximadamente 2 mg/mL de açúcares redutores em 48 horas. As BGLs presentes no extrato enzimático otimizado foram imobilizadas em suporte MANAE-agarose, Concanavalina A-Sepharose e BrCN-Sepharose. Os derivados BGL-MANAE e BGL-ConA foram ativados aproximadamente 10 e 3 vezes, respectivamente. BGL-MANAE e BGL-ConA foram mais estáveis que o controle BGLBrCN em todos os pH testados em 24 horas e, além disso, BGL-ConA permaneceu com 100% de sua atividade em temperaturas de 40 °C, 50 °C e 60 °C, já o BGL-MANAE mostrou-se estável a 40 °C permanecendo com 83% de sua atividade, ambos em 24 horas. BGL-MANAE e BGL-ConA apresentaram menor efeito inibitório em presença de diferentes concentrações de glucose e etanol quando comparados ao BGL-BrCN, e esses resultados indicaram que a imobilização de alguma forma colaborou para uma maior estabilidade ao pH e à temperatura, bem como ao aumento da tolerância por glucose e etanol. Os derivados puderam ser reutilizados por até 20 vezes e quando avaliados quanto à capacidade de clarificar vinhos e sucos de uva (hidrólise de antocianinas), BGL-MANAE clarificou 52% o vinho, 71% o vinho diluído, 77% o suco de uva e 56% o suco de uva diluído, e BGL-ConA em contrapartida clarificou 41% o vinho, 46% o vinho diluído, 63% o suco de uva e 23% o suco de uva diluído. BGL-MANAE foi mais eficiente que BGL-ConA na clarificação de vinhos e sucos de uva podendo ser considerado um biocatalisador promissor na hidrólise de antocianinas e, consequentemente, para a produção de vinhos brancos e rose a partir de diferentes variedades de uvas. Este trabalho pelo que sabemos, é o primeiro a usar BGLs imobilizadas com aplicação na clarificação de sucos de uva e vinhos, podendo ser considerado um trabalho inovador, e de grande importância para a indústria de alimentos e bebidas. / ?-glucosidases are enzymes that catalyze the hydrolysis of ?-1,4, ?-1,3 and ?-1,6 glucosidic linkages, from the non-reducing end of short chain oligosaccharides, alkyl and aryl ?-D-glucosides and disaccharides. Besides being complex key cellulolytic enzymes, they have important functions such as the improvement of wine flavors and anthocyanins hydrolysis. Malbranchea pulchella is usually found in decaying plant debris or in material rich in cellulose, for this reason it can be considered promising for the production of enzymes of biotechnological interest. In this context, the aim of this project was the functional characterization of a ?-glucosidase from M. pulchella and its application in the organic residues and anthocyanins hydrolysis. A BGL GH3 family produced by M. pulchella was purified with a purification factor and recovery of about 6.32 and 35 times. Its approximate molecular mass was 100 kDa, and Km, Vmax and kcat were 0.33 mM, 13.67 U/mg, 26.5 s-1, respectively. The circular dichroism revealed a structure composed of approximately 25% of ?-helix and 20% of ?-sheets. BGL presented optimum pH and temperature at 6.0 and 50 °C; and it was stable at 40 °C. It also showed good stability at pH 5.0 to 8.0, for 24 hours. None of the metal ions salts activated the enzyme and HgCl2 inhibited the activity by 90%. The enzyme showed no inhibition in the presence of glucose (0,1-1M) for 24 hours. Furthermore, it is glycosylated and the sugar proportion correspondsto 15% of the enzyme mass. The effect of cellobiose (C) and sugarcane bagasse in natura (BCAN) in the production of BGLs were evaluated in a CCRD, which indicated a reduced model of influence of the two variables. The best culture condition for BGLs production was 0.6% of C (w/v) and 4% (w/v) of BCAN. Through a mixture design, using the BCAN, ground soybean hulls (CS) and barley bagasse (BCev) were used to evaluate the potential of hydrolysis of these residues in the presence of enzymes present in the enzymatic extract, resulting in a greater efficiency of (BCev) hydrolysis, producing approximately 2 mg/mL of reducing sugars in 48 hours. The BGLs present in the optimized enzyme extract were also used in the immobilization on ionic support MANAE-agarose and affinity support Concanavalin A-Sepharose (ConA-Sepharose). The BGL-MANAE and BGL-ConA derivatives were activated approximately 10 and 3 times, respectively. BGL-MANAE and BGL-ConA were more stable than BGL-BrCN control in all pH tested within 24 hours. In addition, BGL-ConA remained 100% of its activity at 40 °C, 50 °C and 60 °C , and BGL-MANAE was stable at 40 °C and remained 83% of its activity, both in 24 hours. BGL-MANAE and BGL-ConA showed lower inhibitory effect in the presence of different glucose and ethanol concentrations when compared to BGL-BrCN and these results indicate that the immobilization, somehow, cooperated to a greater pH and temperature stability, as well as to increased tolerance by glucose and ethanol. The derivatives could be reused up to 20 times and when they were tested for their capacity to clarify wine and grape juice (anthocyanins hydrolysis), BGL-MANAE clarified 52% wine, 71% diluted wine, 77% grape juice and 56% diluted grape juice. On the other hand, BGL-ConA clarified 41% wine, 46% diluted wine, 63% grape juice and 23% diluted grape juice. BGL-MANAE was more efficient than BGL-ConA in clarifying wines and grape juices and it may be considered a promising biocatalyst in the anthocyanins hydrolysis, and consequently in the production of white and rose wines from different varieties of grapes. This work as we know, is the first to use immobilized BGLs applied in the clarification of grape juice and wine, for this reason, it can be considered an innovative work, and of great importance to the food and beverage industry
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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.
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Reactive replacement and addition of cations in bioclastic silica and calcite

Allan, Shawn Michael. January 2005 (has links)
Thesis (M. S.)--Materials Science and Engineering, Georgia Institute of Technology, 2005. / Committee Chair: Kenneth Sandhage; Committee Members: Joe Cochran, Robert Snyder and Tom Sanders. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Untersuchungen zum Einfluss verschiedener fortpflanzungssteuernder Maßnahmen auf die Fruchtbarkeitsleistung von Jung- und Altsauen unter Großbestandsbedingungen / Investigations to the role of biotechnological interventions in the reproductive performance of gilts and sows in large swine farms

Lau, Holger 31 January 2008 (has links)
No description available.
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Spirulina production in brine effluent from cooling towers

Choonawala, Bilkis Banu January 2007 (has links)
Thesis (M.Tech.:Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2007 xvi, 185 leaves / Spirulina is a blue-green, multicellular, filamentous cyanobacterium that can grow to sizes of 0.5 millimetres in length. It is an obligate photoautotroph and has a pH growth range from 8.3 to 11.0.The large-scale production of Spirulina biomass depends on many factors, the most important of which are nutrient availability, temperature and light. These factors can influence the growth of Spirulina and the composition of the biomass produced by changes in metabolism. Brine effluent from cooling towers of electricity generating plants may provide an ideal growth medium for Spirulina based on its growth requirements, i.e. high alkalinity and salinity. The aim of this research was to optimise brine effluent from cooling towers by supplementing it with salts, in order to use this optimised effluent in a small open laboratory raceway pond in an attempt to increase the biomass production of Spirulina.
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Spirulina production in brine effluent from cooling towers

Choonawala, Bilkis Banu January 2007 (has links)
Thesis (M.Tech.:Biotechnology)-Dept. of Biotechnology, Durban University of Technology, 2007 xvi, 185 leaves / Spirulina is a blue-green, multicellular, filamentous cyanobacterium that can grow to sizes of 0.5 millimetres in length. It is an obligate photoautotroph and has a pH growth range from 8.3 to 11.0.The large-scale production of Spirulina biomass depends on many factors, the most important of which are nutrient availability, temperature and light. These factors can influence the growth of Spirulina and the composition of the biomass produced by changes in metabolism. Brine effluent from cooling towers of electricity generating plants may provide an ideal growth medium for Spirulina based on its growth requirements, i.e. high alkalinity and salinity. The aim of this research was to optimise brine effluent from cooling towers by supplementing it with salts, in order to use this optimised effluent in a small open laboratory raceway pond in an attempt to increase the biomass production of Spirulina.
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Patentes biotecnológicas y genéticas: enfoque jurídico y ético

Bergel, Salvador 10 April 2018 (has links)
Biotechnological and genetic patents: legal and ethical approachBiotechnology’s entry to patentable inventions field and ethical questions generated are studied from the analysis between moral and legal order relationship. There are several cases where standards concerning patents came into conflict with public order idea or moral concerns, such as human cloning processes or genetic identity modification of human beings or animals. Among these problems, patenting of human genetic material is pointed out. Different views on the issue are carefully analyzed; this piece of writing a does not pretend to close the debate but to expose the key points involved. / Desde el análisis de la relación entre moral y orden jurídico, se analiza el ingreso de la biotecnología al campo de las invenciones patentables y los cuestionamientos éticos que ha generado. Varios son los casos en los que las normas relativas a las patentes fueron colisionando con la concepción de orden público o la moral, como, por ejemplo, los procedimientos de clonación humana o de modificación de identidad genética de humanos o animales. Entre estos problemas destaca el referente al patentabilidad del material genético humano. Las posiciones sobre el tema son expuesta con detenimiento y el artículo no pretende cerrar el debate, sino exponer sus aspectos más importantes.
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Biotechnological potential of the red marine alga Hypnea musciformis (HML) applied to Dentistry / AvaliaÃÃo das potencialidades biotecnolÃgicas de lectinas vegetais no diagnÃstico e prevenÃÃo de cÃrie dentÃria

FÃbio Solon Tajra 25 February 2010 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Dental Caries is an infectious disease naturally multi-factorial that begins in the childhood, able to spread its intensity and prevalence according to the mouth ambient conditions of each host. The risk of the patients to develop, in some time of their lives, carious lesions can be measured through a complex analysis using health determinant factors and other specific factors of the health-disease process. Since the dental caries forward diagnostic as well as the review of the auxiliary determinant factors of the dental caries danger evaluation, the treatment becomes simpler, less invasive and costing lower. It has been quite broad-casted lately the use of lectins to diagnose and to prevent some diseases. When dealing with dental caries disease, through many years this strategy has been explored still inceptively. Looking through this perspective, the goal of this trial was to investigate the biotechnological potential of the red marine alga Hypnea musciformis (HML) applied to Dentistry. It is about an explanatory-experimental study of quantitative approach through the health questionnaire and data statistics analysis. The research makes reference to some comparative analysis of salivary tests and the cariogenic activity in twelve year-old students and it searches to evaluate the biotechnological potentialities of the lectin from the red marine alga Hypnea musciformis (HML) in the diagnose and prevention of the dental caries. The concentration area of this trial was the macromolecules/ lectin biotechnological application. In the present trial were compared obtained results through the application of the conventional clinical exams to dental caries and salivary tests of dental caries activity pointed by the CARIOGRAM program in association with lab analysis using specific lectins. From this trial, it has been concluded that, about lectins as a biotechnological potential to prevention and diagnose of the dental caries, it has been noticed that there is recognition of resident glycoconjugate on pacifier saliva of high and low risk observed in immunofluorescence pattern. The results showed that the tested lectin has the capacity to intervene on the bacterial growth in a negative way, it is being distinguished statistically (p<0,01) in relation to control group of saline and BSA. However, inhibition studies of the microbial biofilms using the HML are being programmed to evaluate the using possibility of these protein as biotech input to be used for dental caries prevention. It could be said also that the obtained results by the use of HML in the antimicrobial activity were promising, showing that this lectin has presented antimicrobial activity even on very small amounts. As to the use of these protein in the biofilm formation and developing there was no characteristic pattern. / A cÃrie à uma doenÃa infecciosa de natureza multifatorial que se inicia na infÃncia, podendo aumentar de intensidade e prevalÃncia de acordo com as condiÃÃes do ambiente bucal de cada hospedeiro. O risco do paciente em desenvolver, em algum perÃodo de seu ciclo de vida, lesÃes cariosas pode ser medido atravÃs de uma anÃlise complexa que utiliza os fatores determinantes da saÃde e outros fatores especÃficos do processo saÃde-doenÃa. A partir do diagnÃstico precoce da doenÃa cÃrie, assim como anÃlise dos fatores determinantes auxiliares da avaliaÃÃo do risco de cÃrie, o tratamento torna-se mais simples, menos invasivo e de menor custo. Tem sido bastante difundida ultimamente a utilizaÃÃo de lectinas para diagnÃstico e prevenÃÃo de algumas doenÃas. Em se tratando da doenÃa cÃrie, ao longo de muitos anos, essa estratÃgia tem sido explorada ainda de forma incipiente. Nesta perspectiva, o objetivo deste trabalho foi investigar as potencialidades biotecnolÃgicas da lectina de alga marinha da espÃcie de Hypnea musciformis (HML) aplicadas à odontologia. Trata-se de um estudo explicativo-experimental de abordagem quantitativa atravÃs de questionÃrio de saÃde e anÃlises estatÃsticas de dados. A pesquisa faz referÃncia à uma anÃlise comparativa de testes salivares e atividade cariogÃnica em escolares de 12 anos de idade e a busca avaliar as potencialidades biotecnolÃgicas da lectina de alga marinha da espÃcie de Hypnea musciformis (HML) no diagnÃstico e prevenÃÃo de cÃrie dentÃria. A Ãrea de concentraÃÃo deste estudo MacromolÃtulas / AplicaÃÃo BiotecnolÃgica de Lectinas. No presente estudo, foram comparados os resultados obtidos atravÃs da aplicaÃÃo de exame clÃnico convencional para cÃrie e testes salivares de atividade cariogÃnica apontados pelo programa CARIOGRAM em associaÃÃo com anÃlises laboratoriais com a utilizaÃÃo de lectinas especÃficas. A partir deste estudo, concluiu-se que, em se tratando do uso de lectinas como potencial biotecnolÃgico para a prevenÃÃo e diagnÃstico de cÃrie dentÃria, percebeu-se que hà reconhecimento de glicoconjugados presentes na saliva de pacientes de alto e baixo risco observados em padrÃo de fluorescÃncia. Os resultados demonstram que a lectina testada tem a capacidade de interferir no crescimento bacteriano de forma negativa, sendo estatisticamente significante (p<0,01) em relaÃÃo aos grupos controle de salina e BSA. Entretanto estudos de inibiÃÃo da formaÃÃo de biofilmes microbianos utilizando a HML estÃo sendo programados, para assim avaliar a possibilidade de utilizaÃÃo dessas proteÃnas como insumos biotecnolÃgicos a ser utilizados para prevenÃÃo da cÃrie dentÃria. Pode-se ainda afirmar que os resultados obtidos pelo uso de HML na atividade antibacteriana foram promissores, mostrando que esta lectina apresentou atividade antibacteriana mesmo em quantidades muito pequenas. Quanto ao uso destas proteÃnas na formaÃÃo e desenvolvimento de biofilmes, nÃo houve padrÃo caracterÃstico.

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