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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

Estrat?gias de cultivo para produ??o de biomassa e promotores de crescimento por Herbaspirillum seropedicae BR-11417 / Culture strategies for biomass production and growth promoters by Herbaspirillum seropedicae BR-11417

SCHEIDT, Wagner 27 October 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-20T20:50:53Z No. of bitstreams: 1 2015 - Wagner Scheidt.pdf: 2317119 bytes, checksum: 23f086e6fa2757e68ba3e14cc8297249 (MD5) / Made available in DSpace on 2017-06-20T20:50:53Z (GMT). No. of bitstreams: 1 2015 - Wagner Scheidt.pdf: 2317119 bytes, checksum: 23f086e6fa2757e68ba3e14cc8297249 (MD5) Previous issue date: 2015-10-27 / CAPES / The bacteria Herbaspirillum seropedicae is established as diazotrophic, nitrogen fixing, gram-negative, vibrioid, ?-proteobacteria, showing ability to synthesize phytohormones growth promoters in plants. The goal of this work was to improve the fermentation production of H. seropedicae, seeking the maximum production of cells and indole compounds with process cost reduction. The optimization of the culture medium Yeast Dextrose Glucose Sucrose - DYGS ? was conducted through fermentation tests on shaker. The original carbon sources were replaced, and the concentrations of nitrogen and nutrient sources were optimized through the Central Composite Rotational Design - CCRD (2?). The simplified culture medium obtained was composed of glycerol (5.5g L-1), yeast extract (2.8 g L-1), MgSO4?7H2O (0.5 g L-1) e K2HPO4 (0.5 g L-1). This medium provided an increase of 87.5 % in biomass production, and is 49.8 % cheaper than the traditional culture medium DYGS. An experimental design CCRD (2?) was carried with the purpose of improving the operational conditions of the bioreactor and the best growing condition was obtained at 35 ?C, 3 LPM of aeration rate, and 180 RPM of agitation speed. Under these conditions, and using the previously optimized culture medium, the maximum cell production (X= 3.23 g L-1) as well as the maximum metabolic product (P= 9.02mg L-1) were obtained. It was also tested a culture medium with glycerol and yeast extract concentrations increased to 8.0 g L-1 and 4.0 g L-1, respectively. Under these conditions, it was observed that the maximum cell production and metabolic product increased to X = 4.18 g L-1 and P = 11.74 mg L-1, respectively. An appropriate mathematical computer simulation model was developed and used to describe the dynamic behavior of the main variables of fermentation bioreactor. However, there was some difficulty to reproduce appropriately the profiles of all variables, probably due to the specific characteristics of this fermentation process, and the necessity of a mathematical model that takes into account parameters associated to limitations and inhibitions caused by substrate and product. / A bact?ria Herbaspirillum seropedicae ? estabelecida como sendo diazotr?fica fixadora de nitrog?nio, gram-negativa, vibri?ide, membro da classe ? das proteobact?rias, apresentando a capacidade de produ??o de fitohorm?nios promotores do crescimento em plantas. Este trabalho apresentou como objetivos aprimorar o processo fermentativo de produ??o de H. seropedicae, buscando a m?xima produ??o de c?lulas e compostos ind?licos, com redu??o de custos do processo. Realizou-se a otimiza??o do meio de cultura Dextrose Yeast Glucose Sucrose modificado ? DYGS ? atrav?s de ensaios fermentativos em shaker. Substitu?ram-se as fontes de carbono originais e aperfei?oaram-se as concentra??es dos demais componentes atrav?s da matriz experimental 2? obtida atrav?s do Delineamento Composto Central Rotacional ? DCCR. Obteve-se um meio de cultura simplificado, composto por glicerol (5,5 g L-1), extrato de levedura (2,8 g L-1), MgSO4?7H2O (0,5 g L-1) e K2HPO4 (0,5 g L-1) que se apresentou 49,8 % mais barato e com capacidade de produ??o de c?lulas 87,5 % maior quando comparado ao meio DYGS. Atrav?s da DCCR (2?) aprimorou-se tamb?m as condi??es operacionais de biorreator, obtendo-se a melhor condi??o de cultivo a temperatura de 35 ?C, aera??o de 3 LPM e agita??o de 180 RPM. Nestas condi??es, com o meio de cultura otimizado, obteve-se a produ??o celular m?xima de X = 3,23 g L-1 e de produto metab?lico m?ximo de P = 9,02 mg L-1. Testou-se um meio de cultura com concentra??es de glicerol e de extrato de levedura aumentadas para 8,0 g L-1 e 4,0 g L-1, respectivamente, sendo observada uma produ??o celular m?xima de X = 4,18 g L-1 e de produto metab?lico m?ximo de P = 11,74 mg L-1. Avaliou-se atrav?s de simula??o computacional, o modelo matem?tico mais adequado para descrever o comportamento din?mico das principais vari?veis das fermenta??es em biorreator. Contudo, observou-se uma alta dificuldade em descrever adequadamente os perfis de todas as vari?veis avaliadas, provavelmente devido ?s caracter?sticas espec?ficas deste processo fermentativo e ? necessidade de um modelo que leve em considera??o par?metros de limita??es e inibi??es causadas pelo substrato e produto.
2

Sele??o de bact?rias diazotr?ficas solubilizadoras de f?sforo e seu efeito no desenvolvimento de plantas de arroz

Bonilla, German Andres Estrada 09 June 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-17T14:23:26Z No. of bitstreams: 1 2011- German Andres Estrada Bonilla.pdf: 1652819 bytes, checksum: 24a4d4664a65dfad88ccdfe17b4a0c02 (MD5) / Made available in DSpace on 2016-08-17T14:23:26Z (GMT). No. of bitstreams: 1 2011- German Andres Estrada Bonilla.pdf: 1652819 bytes, checksum: 24a4d4664a65dfad88ccdfe17b4a0c02 (MD5) Previous issue date: 2011-06-09 / Rice (Oryza sativa L.) is one of the major world crops, being widely consumed among people from five continents. In recent years research have increased in relation to the use of plant growth promoting diazotrophic bacteria (PGPB) as a possible solution to reduce the use of chemical nitrogen and phosphate fertilizers. Thus, this study aimed to evaluate the physiological potential and inorganic phosphate (IP) solubilization capacity of different diazotrophic strains isolated from rice plants grown in different regions of Brazil as well as to evaluate their role in the development of rice plants. Firstly, the culture media employed to test the phosphate solubilization in petri dishes were standardized. In this study 49 strains were tested for their capability of solibilizing tricalcium phosphate in NBRIP and GL solid media. Afterwards, the soluble P, pH, population and the index of solubilization (IS) were quantified for 7 IP solubilizing strains grown in the NBRIP liquid medium. The IP solubilizing isolates were also tested for the production of indolic compounds (IAA) and the nitrogen fixation capacity through the acetylene reduction activity (ARA). The isolates were taxonomical identified through the amplification and partial sequencing of 16S RNAr and nifH genes. Three of these strains and the controls H. seropedicae ZAE94, G diazotrophicus PAL5 and A.chroochoccum AC1 were tested in greenhouse conditions in association with rice plants. All strains that solubilized IP in NBRIP liquid medium decreased the medium pH while the bacterial population remained around 108 cfu ml-1 for up to 15 days. All strains were capable to produce indole compounds and reduced acetylene. The partial analysis of 16S RNAr and nifH gene indicated the identification of the species Herbaspirillum seropedicae, Burkholderia vietnamiensis and B. kururiensis species. All strains showed an increase in the range of 33 and 47% in grain yield when tricalcium phosphate (PTC) was applied and between 18 and 44% when PSS (simple superphosphate) was used. In general, all of the strains stimulated an increase of total P in the grain and a greater harvest index. The use of these strains as bioinculant is promising and therefore it is necessary to test in the field conditions / O arroz (Oryza sativa L.) ? uma das principais culturas cultivadas, sendo amplamente consumida nos cinco continentes. Nos ?ltimos anos as pesquisas t?m aumentado em rela??o ao uso de bact?rias diazotr?ficas e promotoras de crescimento vegetal (BPCV), como uma poss?vel solu??o para diminuir o uso de fertilizantes qu?micos nitrogenados e fosfatados. Desta forma, este trabalho teve por objetivo avaliar o potencial fisiol?gico e a capacidade de solubiliza??o de fosfato inorg?nico (PI) de diferentes estirpes de bact?rias diazotr?ficas oriundas de plantas de arroz cultivadas em diferentes regi?es do Brasil e seu papel no desenvolvimento de plantas de arroz. Primeiramente foi padronizado o meio de cultura a ser empregado nos ensaios de solubiliza??o de fosfato inorg?nico em placas de petri. Neste estudo foram testadas 49 estirpes em quanto sua capacidade de solubilizar fosfato tric?lcico (PTC) nos meios s?lidos NBRIP e GL. Em seguida foi quantificado o P sol?vel, pH, a popula??o de bact?rias e ?ndice de solubiliza??o (IS) das 7 estirpes solubilizadoras de PI em meio l?quido NBRIP. As estirpes solubilizadoras de PI tamb?m foram testadas quanto ? produ??o de compostos ind?licos (AIA) e capacidade de fixar nitrog?nio atrav?s da atividade de redu??o e acetileno (ARA). As estirpes foram identificadas atrav?s da amplifica??o e do sequenciamento parcial dos genes 16S RNAr e gene nifH. Tr?s destas estirpes foram testadas em condi??es de casa de vegeta??o junto com os controles Herbaspirillum seropedicae BR11417 (ZAE94), Gluconacetobacter diazotophicus BR11281 (PAL5) e Azotobacter Chroochoccum AC1 quanto ? capacidade de aumentar o desenvolvimento e produ??o de plantas de arroz. Todas as estirpes que solubilizaram PI no meio de cultura NBRIP l?quido influenciaram na diminui??o do pH do meio enquanto que a popula??o se manteve em torno de 108 ufc.ml-1 por at? 15 dias. Todas as estirpes apresentaram capacidade de produzir compostos ind?licos e foram capazes de reduzir acetileno. A an?lise parcial do gene 16S RNAr e do gene nifH das sete estirpes possibilitou a identifica??o das esp?cies Herbaspirillum seropedicae, Burkholderia vietnamiensis e B. kururiensis. Todas as estirpes promoveram um aumento na produ??o de massa seca nos gr?os entre 33 e 47% quando foi utilizado o PTC e de 18 a 44% quando foi utilizado o fosfato super simples (PSS). Em geral, todas as estirpes estimularam um maior acumulo de N e P total no gr?o e um maior ?ndice de colheita. O uso dessas estirpes como bioinoculante ? bastante promissor e portanto torna-se necess?rio test?-las em condi??es de campo.

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