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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.
91

Estudo cinético e do equilíbrio da biossorção dos íons chumbo e cobre pela macroalga Sargassum sp. em sistemas monocomponente e binário / Kinetic and equilibrium study of biosorption of lead and copper ions by sargassum seaweed in nanocomponent and binary systems

Karla Acemano de Jesus 08 February 2010 (has links)
As algas marrons do gênero Sargassum têm sido estudadas como potenciais candidatas ao processo de biossorção, objetivando tratar efluentes contaminados com metais pesados. A estrutura celular deste gênero de alga apresenta moléculas carregadas, como o ácido algínico, capazes de atrair e captar cátions metálicos. A proposta deste trabalho foi avaliar a capacidade de captação dos íons cobre e chumbo pela alga marinha Sargassum através de ensaios cinéticos e de acumulação com modelagem cinética e das isotermas para sistemas monocomponente e binário. O equilíbrio de captação foi atingido em 30 minutos e a cinética do processo foi representada por um modelo de segunda ordem. No sistema monocomponente, onde as soluções continham inicialmente 10 mg/L de cada íon metálico a captação no equilíbrio foi 0,06 mmol/g de íons Cu (II) e 0,02 mmol/g de íons Pb (II). Para as soluções contendo 50 mg/L a captação no equilíbrio foi 0,37 mmol/g de íons Cu (II) e 0,11 mmol/g de íons Pb (II), individualmente. A capacidade de biossorção foi reduzida no sistema binário mostrando que a presença de um segundo metal afeta a captação dos íons. Os valores de qmax para íons Pb (II) no sistema binário foi 0,6 mmol/g contra 1,2 mmol/g no sistema monocomponente; para íons Cu (II) a captação foi 0,7 mmol/g contra 1,8 mmol/g. Na biossorção binária a captação de íons Pb (II) manteve o percentual de remoção mesmo em soluções com elevadas concentrações de íons Cu (II); o contrário não foi observado para o Pb(II), indicando que íons Pb (II) interferem mais na captação de íons Cu (II). Para o estudo do equilíbrio monocomponente foram utilizados os modelos de Langmuir e Freundlich; para o sistema binário, o Langmuir competitivo, Langmuir modificado, Langmuir-Freundlich e Freundlich estendido. Os modelos não foram conclusivos, porém elucidaram aspectos relacionados ao mecanismo, apresentando alto grau de dispersão entre a captação experimental e as teóricas. / Brown seaweeds from the genus Sargassum are widely studied for use as potential candidates for biosorption purposes, particularly in the treatment of heavy-metals contaminated effluents. The cellular structure of this seaweed presents charged molecules, such as alginic acid, able to attract and recover metal cation ions. The objective of this work was to study the uptake capacity of copper and lead by the seaweed Sargassum, through kinetic and isotherm studies with the help of kinetic and isotherm models for monocomponent and binary solutions. Equilibrium uptake was reached in 30 minutes and the kinetic behavior of the process followed a second-order model. In monocomponent systems, at 10 mg/L metal concentration, equilibrium uptake indicated a recovery of 0.06 mmol Cu(II)/g biomass and 0.02mmol/g Pb(II)/g biomass. When a 50 mg/L solution was used, the individual uptake was equal to 0.37 mmol Cu(II)/g biomass and 0.11 mmol Pb(II)/g biomass. Uptake was markedly reduced by the presence of the second metal in solution indicating the interference in biosorption in a multi-ion solution. Values of qmax for Pb(II) in the binary system was equal to 0.6 mmol/g biomass, against 1.2 mmol/g biomass in the monocomponent situation; for Cu(II) the uptake was equal to 0.7 mmol/g biomass against 1.8 mmol/g biomass, in the monocomponent solution. In the binary solution, Pb(II) uptake kept the same percent removal, even in the presence of high concentrations of Cu(II); an opposite behavior was observed for Cu(II), indicating that Pb(II) interfere in the uptake of Cu(II) more than the opposite situation. In the monocomponent equilibrium models such as Langmuir and Freundlich were used to fit experimental data. In binary systems, Competitive Langmuir, Modified Langmuir, Langmuir-Freundlich and Extended Freundlich Extented were used. All the models were not conclusive to fit experimental results, however they contributed for a better understanding of the mechanism involved in biosorption, because a high level of dispersion between actual biosorption and theoretical prediction was observed.
92

Condição trófica em rios do estado de Minas Gerais / Trophic status in rivers of the state of Minas Gerais

Silva, Edson Faria da 17 February 2012 (has links)
Made available in DSpace on 2015-03-26T13:23:57Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2233075 bytes, checksum: dd119ccbefb7f1b9f96d58ee15100e8e (MD5) Previous issue date: 2012-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Eutrophication is an important process that may impair water quality. The dynamics of this process in lotic water bodies is little studied, when compared with the studies in lentic bodies as lakes, lagoons and reservoirs. To carry out this study, we used data of the main variables used to assess the trophic status: chlorophyll-a, total phosphorus, nitrate, organic nitrogen, ammoniacal nitrogen, total nitrogen and turbidity. These data were derived from the monitoring network for surface waters of the Minas Gerais state, IGAM Institute database, period from 2007 to 2011, totaling 290 sampling points, covering the major river basins of the Minas Gerais state. There was no significant difference between the values of total phosphorus due to seasonality, however the area of the basin influences greatly the behavior of this variable. Comparisons among chlorophyll-a and other data showed reasonable correlation. We calculated the trophic state index using the methods proposed by Carlson (1977), Kratzer Brezonik (1981),Yoshimi (1987), Carlson modified by Toledo et al. (1990), Lamparelli (2004), and Sorrel (2006), in order to verify that would provide similar results. Regarding the methods of predicting the trophic state, it was found that the index proposed by Lamparelli (2004) presents advantages such as simplicity and good performance. / A eutrofização é um importante processo que pode comprometer a qualidade das águas. A dinâmica deste processo em corpos hídricos lóticos é pouco estudada, quando compara-se com o número de estudos em corpos lênticos, como lagos, lagoas e represas. Para a realização dessa pesquisa, foram utilizados dados das principais variáveis usadas na avaliação do grau de trofia: clorofila-a, fósforo total, nitrato, nitrogênio orgânico, nitrogênio amoniacal, nitrogênio total e turbidez. Esses dados foram provenientes da rede de monitoramento de águas superficiais do estado de Minas Gerais, banco de dados do IGAM, período de 2007 a 2011, totalizando 290 pontos de amostragem, abrangendo os rios das principais bacias do estado de Minas Gerais. Não houve diferença significativa entre os valores de fósforo total em função da sazonalidade, entretanto a área da bacia influencia, sobremaneira, o comportamento dessa variável. As comparações entre clorofila-a e demais dados apresentaram correlação razoável. Calculou-se o Índice de Estado Trófico utilizando os métodos propostos por Carlson (1977), Kratzer e Brezonik (1981), Yoshimi (1987),Carlson modificado por Toledo et al. (1990), Lamparelli (2004), e Sorrel (2006), a fim de se verificar se proporcionariam resultados semelhantes. Em relação aos métodos de predição de trofia, verificou-se que o Índice proposto por Lamparelli (2004) apresenta vantagens como simplicidade e bom desempenho.
93

Atividades antinociceptiva e anti-inflamat?ria de uma fra??o rica em heterogalactana sulfatada extra?da da alga Codium isthmocladum (Vickers 1905)

Cordeiro, Sara Lima 11 March 2013 (has links)
Made available in DSpace on 2014-12-17T14:03:43Z (GMT). No. of bitstreams: 1 SaraLC_DISSERT.pdf: 1277760 bytes, checksum: 4ab6e4050b3bef93e51e123918051267 (MD5) Previous issue date: 2013-03-11 / Sulfated polysaccharides comprise a complex group of macromolecules with a range of several biological activities, including antiviral activity, anticoagulant, antiproliferative, antiherp?tica, antitumor, anti-inflammatory and antioxidant. These anionic polymers are widely distributed in tissues of vertebrates, invertebrates and algae. Seaweeds are the most abundant sources of sulfated polysaccharides in nature. The green algal sulfated polysaccharides are homo or heteropolysaccharides comprised of galactose, glucose, arabinose and/or glucuronic acid. They are described as anticoagulant, anti-inflammatory, antiviral, anti-angiogenic, antitumor compounds. However, there are few studies about elucidation and evaluation of biological/pharmacological effects of sulfated polysaccharides obtained from green algae, for example, there is only one paper reporting the antinociceptive activity of sulfated polysaccharides of these algae. Therefore this study aimed to obtain sulfated polysaccharides of green seaweed Codium isthmocladum and evaluates them as potential antinociceptive agents. Thus, in this study, the total extract of polysaccharides of green alga C. isthmocladum was obtained by proteolytic digestion, followed by fractionation resulting in five fractions (F0.3, F0.5, F0.7, F0.9 and F1.2) by sequential precipitation with acetone. Using the test of abdominal contractions we observed that the fraction F0.9 was the most potent antinociceptive aompound. F0.9 consists mainly of a sulfated heterogalactana. More specific tests showed that Fo.9 effect is dose and time dependent, reaching a maximum at 90 after administration (10 mg / kg of animal). F0.9 is associated with TRPV1 and TRPA1 receptors and inhibits painful sensation in animals. Furthermore, F0.9 inhibits the migration of lymphocytes induced peritonitis test. On the other hand, stimulates the release of NO and TNF-?. These results suggest that F0.9 has the potential to be used as a source of sulfated galactan antinociceptive and anti-inflammatory / Os polissacar?deos sulfatados comp?em um grupo complexo de macromol?culas com uma gama de importantes atividades biol?gicas, incluindo atividade antiviral, anticoagulante, antiproliferativa, antiherp?tica, antitumoral, antiinflamat?ria e antioxidante. Esses pol?meros ani?nicos s?o amplamente distribu?dos em tecidos de vertebrados, invertebrados e algas. As algas marinhas s?o as fontes mais abundantes de polissacar?deos sulfatados na natureza. Os polissacar?deos sulfatados de algas verdes s?o homo ou heteropolissacar?deos compostos por galactose, glicose, arabinose e/ou ?cido glucur?nico. Para estes pol?meros s?o descritas atividades como anticoagulante, anti-inflamat?ria, antiviral, antiangiog?nica, antitumoral. Por?m, ainda h? poucos estudos de elucida??o e avalia??o de atividades biol?gicas/farmacol?gicas de polissacar?deos sulfatados obtidos de algas verdes, por exemplo, h? somente um trabalho relatando a atividade antinociceptiva de polissacar?deos sulfatados destas algas. Portanto este trabalho teve como objetivo obter polissacar?deos sulfatados da alga verde Codium isthmocladum e avalia-los como poss?veis agentes antinociceptivos. Assim, no presente estudo, o extrato total de polissacar?deos da alga verde C. isthmocladum foi obtido atrav?s de digest?o proteol?tica, seguida de fracionamento resultando em cinco fra??es (F0.3; F0.5; F0.7; F0.9 e F1.2) por precipita??o sequencial com acetona. Com o teste de contra??es abdominais observou-se que a fra??o F0.9 foi o mais potente antinociceptivo. F0.9 ? composta principalmente por uma heterogalactana sulfatada. Ensaios mais espec?ficos mostraram que o seu efeito ? dose e tempo dependente, chegando ao m?ximo com 90 ap?s a administra??o (10 mg/kg de animal). F0.9 se associa a receptores TRPV1 e TRPA1 e inibe sensa??o dolorosa em animais. Al?m disso, F0.9 inibe a migra??o de linf?citos em ensaios de peritonite induzida. Por outro lado estimula a libera??o de NO e TNF-?. Esses resultados sugerem que F0.9 tem potencial para ser usada como fonte de galactana sulfatada antinociceptiva e anti-inflamat?ria
94

Extra??o, caracteriza??o estrutural parcial e atividades farmacol?gicas do olginato obtido da alga marrom Lobophora variegata (Lamouroux) Oliveira Filho, 1977

Almeida, Hugo Wescley Barros 28 February 2014 (has links)
Made available in DSpace on 2014-12-17T14:03:44Z (GMT). No. of bitstreams: 1 HugoWBA_DISSERT.pdf: 1563778 bytes, checksum: ea0b3bf4e13c36f81c11450e423c8df4 (MD5) Previous issue date: 2014-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The alginic acid or alginates are acidic polysaccharides found in brown seaweed widely used in food, cosmetic, medical and pharmaceutical industry. This paper proposes the extraction, chemical characterization and verification of the pharmacological activities of brown seaweed variegata Lobophora . The alginate was extracted from the seaweed Lobophora variegata and part was sulphated for comparative purposes. The native extract showed 42% total sugar, 65% uronic acid, 0,36 % protein and 0% of sulfate, while the sulfate showed 39% , 60%, 0.36% and 27,92 % respectively. The presence of a sulfate group may be observed by the metachromasia with toluidine blue in electrophoresis system and characteristic vibration 1262,34 cm-1 in infrared spectroscopy connections assigned to S = O. We observed the formation of films and beads of native alginate, where more concentrated solution 6% resulted in a thicker and more consistent film. Native alginate showed proliferative activity at concentrations (25 and 50 mcg), (50 mg) and (100 mg) in 3T3 cell line in 24h, 48h and 72h, respectively , as the sulfated (100 mg) in 24 . Also showed antiproliferative or cytotoxic activity in HeLa cells of strain, (25 and 100 mg), (25 and 100 mg) and (25, 50 and 100 mg), to native, now for the sulfate concentrations (100 mg) in 24 (25, 50 and 100 mg) in 48 hours, and (50 and 100 mg ) 72h. For their antioxidant activity, the sulfated alginates have better total antioxidant activity reaching 29 % of the native activity while 7.5 % of activity . For the hydroxyl radical AS showed high inhibition ( between 77-83 % ) in concentrations, but the AN surpassed these numbers in the order of 78-92 % inhibition. The reducing power of AN and AS ranged between 39-82 % . In the method of ferric chelation NA reached 100 % chelating while the AS remained at a plateau oscillating 6.5%. However, in this study , we found alginates with promising pharmacological activities, to use in various industries as an antioxidant / anti-tumor compound / Os ?cidos alg?nicos ou alginatos s?o polissacar?deos ?cidos presentes em algas marrons amplamente utilizadas na ind?stria de alimentos, est?tica, m?dica e farmac?utica. Este trabalho prop?e a extra??o, caracteriza??o qu?mica e verifica??o das atividades farmacol?gicas da alga marinha marrom Lobophora variegata. O alginato foi extra?do da alga Lobophora variegata e parte foi sulfatado para fins comparativos. O extrato nativo apresentou 42% de a??car total, 65% de ?cido ur?nico, 0,36% de prote?na e 0% de sulfato, enquanto a sulfatada apresentou 39%, 60%, 0,36% e 27,92% respectivamente. A presen?a do grupo sulfato pode ser verificada atrav?s da metacromasia com o corante azul de toluidina no sistema de eletroforese e vibra??o caracter?stica em 1262,34 cm-1 na espectroscopia de infravermelho, atribu?do a liga??es S=O. Observou-se a forma??o de filmes e esferas de alginato nativo, onde a solu??o mais concentrada 6%, resultou em um filme mais espesso e consistente. O alginato nativo apresentou atividade proliferativa nas concentra??es (25 e 50?g), (50 ?g) e (100 ?g) em linhagem celular 3T3 em 24h, 48h e 72h, respectivamente, j? o sulfatado em (100 ?g) em 24h. Apresentou tamb?m atividade antiproliferativa ou citot?xica em c?lulas da linhagem HeLa, com (25 e 100 ?g), (25 e 100 ?g) e (25, 50 e 100 ?g), para o nativo, j? para a sulfatada nas concentra??es (100 ?g) em 24h, (25, 50 e 100 ?g) em 48h, e (50 e 100 ?g) 72h. Quanto a atividade antioxidante, os alginatos sulfatados apresentam melhor atividade antioxidante total chegando a 29% de atividade enquanto o nativo 7,5% de atividade. Para o radical hidroxila o AS apresentou alta inibi??o (entre 77-83%) nas concentra??es testadas, por?m o AN superou estes n?meros na ordem de 78-92% de inibi??o. O poder redutor de AN e AS variou entre 39-82%. Na metodologia de quela??o f?rrica, o NA chegou a 100% de quela??o, enquanto o AS permaneceu em um plat? oscilando em 6,5%. Contudo, neste trabalho, pudemos constatar alginatos com promissoras atividades farmacol?gicas, com uso nas diversas ind?strias como um composto antioxidante/antitumoral
95

Atividade anticoagulante, antioxidante e antitumoral de heterofucanas da alga Dictyopteris delicatula (Lamouroux, 1809)

Magalhaes, Kaline Dantas 02 December 2011 (has links)
Made available in DSpace on 2014-12-17T14:13:58Z (GMT). No. of bitstreams: 1 KalineDM_DISSERT.pdf: 984274 bytes, checksum: 8150a2011f0eac140bc8113ffa4bc1ea (MD5) Previous issue date: 2011-12-02 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the present study, six families of sulfated polysaccharides were obtained from seaweed Dictyopteris delicatula (Lamouroux, 1809) and their anticoagulant, antioxidant and antitumor activities were evaluated. All fractions showed anticoagulant activity on aPTT assay, but not on PT assay. Fractions also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. Thus, six fractions (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) we obtained by proteolytic digestion, followed by acetone fractionation and molecular sieving on Sephadex G-100. Chemical analyses demonstrated that all polysaccharides contain heterofucans composed mainly of fucose, xylose, glucose, galactose, uronic acid, and sulfate. Any fractions changed the PT. However, all fractions were able on double the aPPT on a dose-dependent manner. The heterofucans F0.7v and F1.0v showed low anticoagulant activity while F1.5v presented the most prominent anticoagulant activity .When compared to Clexane?, a low molecular weight heparin, at same concentration F1.5v presented similar anticoagulant activity. The fucans F0.5v and F0.7v at 1.0 mg/mL showed high ferric chelating activity (~45%), whereas fucans F1.3v (0.5 mg/mL) showed considerable reducing power, about 53.2% of the activity of vitamin C. The fucan F1.5v presented the most prominent anticoagulant activity. The best antiproliferative activity was found with fucans F1.3v and F0.7v. However, F1.3v activity was much higher than F0.7v inhibiting almost 100% of HeLa cell proliferation. These fucans have been selected for further studies on structural characterization as well as in vivo experiments, which are already in progress / No presente estudo, seis popula??es de polissacar?deos sulfatados foram obtidas a partir da alga Dictyopteris delicatula (Lamouroux, 1809) e suas atividades anticoagulante, antioxidante e antitumoral avaliadas. Deste modo, as seis fra??es (F0.5v, F0.7v, F1.0v, F1.3v, F1.5v e F2.0v) foram obtidas por prote?lise seguida por fracionamento de acetona e gel filtra??o molecular Sephadex G-100. Todas as fra??es apresentaram atividade anticoagulante frente ao ensaio de aPTT, mas n?o sobre o ensaio de PT. As heterofucanas exibiram atividade antioxidante total, capacidade em sequestrar radicais super?xido e propriedade de quelar ferro. As an?lises qu?micas demonstraram que todos os polissacar?deos cont?m heterofucanas composta principalmente por fucose, xilose, glicose, galactose, ?cido ur?nico, e sulfato. Nenhuma das fra??es alterou o PT. Entretanto, todas as fra??es foram capazes de dobrar o aPTT de uma maneira dose dependente. As heterofucanas F0.7v e F1.0v demonstraram baixa atividade anticoagulante, enquanto a F1.5v apresentou a maior atividade anticoagulante e quando comparada com Clexane?, uma heparina de baixo peso molecular, em mesma concentra??o, apresentou antividade anticoagulante semelhante. As fucanas F0.5v e F0.7v a 1,0 mg/mL mostraram alta atividade de quela??o ferica (~ 45%), enquanto a fucana F1.3v (0,5 mg/mL) mostrou consider?vel potencial redutor, cerca de 53,2% da atividade da vitamina C. A melhor atividade antitumoral foi encontrada nas fucanas F1.3v e F0.7v. No entanto, a atividade F1.3v foi muito superior a F0,7v, quase 100% de inibi??o da prolifera??o de c?lulas HeLa (c?lula de c?ncer de colo de ?tero). Estas fucanas foram selecionadas para novos estudos sobre caracteriza??o estrutural, bem como em experimentos in vivo, que j? est?o em andamento / 2020-01-01
96

Processo de desidrata??o da alga Gracilaria birdiae beneficiada em laborat?rio e artesanalmente: an?lise da atividade antioxidante e composi??o centesimal

Paiva, Mirely de Freitas 26 November 2010 (has links)
Made available in DSpace on 2014-12-17T14:16:28Z (GMT). No. of bitstreams: 1 MirelyFP_DISSERT_PARCIAL.pdf: 786643 bytes, checksum: 4acab041106a30bcf7d8494f27443eb4 (MD5) Previous issue date: 2010-11-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The main aim of this study was to compare the procedure for dehydration of Gracilaria birdiae prepared handmade and laboratory, collected in the northern coast of Rio Grande do Norte. The sample was collected in the Rio do Fogo beach in march 2009. The sample collected followed by two processing, the first the material prepared in laboratory was air-dried at 50?C for 24 hours in air-flow oven. The second the handmade sample was air-dried on the sun during three days. The extract was prepared in three different solvents: ethanol, hydroethanol and water, resulting in ethanol, hidroethanol and aqueous extracts from handmade and laboratory sample. In according with results only the ethanol extract was fractionated yielding the fractions hexane, dichloromethane and ethyl acetate fractions. The different process to obtain Gracilaria birdiae resulted in the samples with different shades. The soluble solids content was higher in the laboratory sample. The chemical composition the both samples were characterized by presenting a considerable amounts of carbohydrates, with amior percentage protein and ash, respectively, in the handmade and laboratory sample. In two samples showed a low content of lipids and the lipid profile showed a higher proportion of monounsaturated fatty acids, with the absence polyunsaturated handmade sample. The phytochemical screening by chemical reactions showed the presence of flavonoids, tannins, alkaloids and saponins the laboratory sample, presenting a greater diversity of bioactive compounds. Through of the analysis by thin layer chromatography was possible to identify the phytosterols ?-sitosterol and stigmasterol the both samples, also suggest the presence of ?-carotene and chlorophyll ? the laboratory sample. The levels of total phenolics and flavonoids were more significant in the ethanol extract of the laboratory sample. The in vitro lethality showed that extracts of the laboratory sample and handmade from 125 to 500 ?g/ mL, respectively, were highly lethal. In the evaluation of antioxidant capacity by the system ?-carotene/?cido linoleic method and by DPPH radical scavernging assay, the ethanol extract from the laboratory process showed significantly greater activity than the other extracts, being and the first and second methods, respectively, lower and equivalent to the synthetic antioxidant BHT. The handmade ethanol extract has not demonstrated skill in deactivating free radicals, but showed activity in inhibiting lipid peroxidation, although the values were significantly lower than the laboratory sample. We conclude that the dehydration process in the laboratory is the most efficient technique to maintenance of the chemical composition present in the seaweed, providing beneficial properties such as antioxidant capacity. We emphasize that this property can be explored with the objective of adding commercial value to the final product, which will promote the expansion of production of this seaweed in the community of Rio do Fogo / O presente estudo tem como finalidade analisar de forma comparativa o procedimento de desidrata??o de Gracilaria birdiae beneficiada laboratorialmente e artesanalmente, cultivada no litoral norte do Rio Grande do Norte. A coleta das amostras foi realizada na praia do Rio do Fogo em mar?o de 2009. Das amostras coletadas seguiram-se dois processamentos, no primeiro o material coletado foi mantido em estufa de ar circulante a 50?C, por 24 horas sendo obtida a amostra laboratorial. No segundo a amostra artesanal foi desidrata??o ao sol por um per?odo de tr?s dias. A extra??o consistiu em solu??es etan?lica, hidroetan?lica e aquosa, resultando em extrato etan?lico, hidroetan?lico e aquoso. De acordo com os resultados o extrato etan?lico foi fracionamento obtendo as fra??es hexano, diclorometano e acetato de etila. As distintas formas de processamento da Gracilaria birdiae promoveram a obten??o de amostras com tonalidades distintas. Quanto ao teor de s?lidos sol?veis a amostra laboratorial apresentou superioridade. A composi??o centesimal de ambas as amostras caracterizaram-se por apresentar um consider?vel teor de carboidratos, com maior percentual de res?duo mineral e prote?nas, respectivamente, na amostra laboratorial e artesanal. As duas amostras apresentaram um baixo conte?do de lip?deos e um perfil lip?dico caracterizado por uma maior propor??o de ?cidos graxos monoinsaturados, com aus?ncia de poliinsaturados na amostra artesanal. A triagem fitoqu?mica evidenciou a presen?a de flavon?ides, taninos, saponinas e alcal?ides na amostra laboratorial, apresentando uma maior diversidade de compostos bioativos. Por meio da cromatografia em camada delgada foi poss?vel identificar os fitoester?is ?-sitosterol e stigmasterol em ambas as amostras, al?m de sugerir a presen?a do ?-caroteno e da clorofila ? na amostra laboratorial. Os teores de compostos fen?licos totais e caroten?ides totais foram mais expressivos no extrato etan?lico da amostra laboratorial. A letalidade in vitro, demonstrou que os extratos etan?licos da amostra laboratorial e artesanal a partir de 500 e 125 ?g/mL, respectivamente, foram altamente letais. Na avalia??o da capacidade antioxidante pelo sistema ?- caroteno/?cido linol?ico e pelo m?todo de sequestro do radical livre DPPH , o extrato etan?lico proveniente do processo laboratorial apresentou atividade significativamente maior que os demais extratos, sendo no primeiro e segundo m?todo, respectivamente, inferior e equivalente ao antioxidante sint?tico BHT. O extrato etan?lico proveniente do processo artesanal n?o demonstrou habilidade na desativa??o de radicais livres, mas apresentou atividade na inibi??o da peroxida??o lip?dica, por?m com valores significativamente inferiores a amostra laboratorial. Conclui-se que o processo de desidrata??o em laborat?rio ? a t?cnica mais eficiente, por supostamente promover a manuten??o dos compostos qu?micos presentes na alga marinha, proporcionando propriedades ben?ficas como a capacidade antioxidante. Ressalta-se que esta propriedade pode ser explorada com o intuito de agregar valor comercial ao produto final, o que promover? a expans?o da produ??o desta alga na comunidade do Rio do Fogo / 2020-01-01
97

Estudo cinético e do equilíbrio da biossorção dos íons chumbo e cobre pela macroalga Sargassum sp. em sistemas monocomponente e binário / Kinetic and equilibrium study of biosorption of lead and copper ions by sargassum seaweed in nanocomponent and binary systems

Karla Acemano de Jesus 08 February 2010 (has links)
As algas marrons do gênero Sargassum têm sido estudadas como potenciais candidatas ao processo de biossorção, objetivando tratar efluentes contaminados com metais pesados. A estrutura celular deste gênero de alga apresenta moléculas carregadas, como o ácido algínico, capazes de atrair e captar cátions metálicos. A proposta deste trabalho foi avaliar a capacidade de captação dos íons cobre e chumbo pela alga marinha Sargassum através de ensaios cinéticos e de acumulação com modelagem cinética e das isotermas para sistemas monocomponente e binário. O equilíbrio de captação foi atingido em 30 minutos e a cinética do processo foi representada por um modelo de segunda ordem. No sistema monocomponente, onde as soluções continham inicialmente 10 mg/L de cada íon metálico a captação no equilíbrio foi 0,06 mmol/g de íons Cu (II) e 0,02 mmol/g de íons Pb (II). Para as soluções contendo 50 mg/L a captação no equilíbrio foi 0,37 mmol/g de íons Cu (II) e 0,11 mmol/g de íons Pb (II), individualmente. A capacidade de biossorção foi reduzida no sistema binário mostrando que a presença de um segundo metal afeta a captação dos íons. Os valores de qmax para íons Pb (II) no sistema binário foi 0,6 mmol/g contra 1,2 mmol/g no sistema monocomponente; para íons Cu (II) a captação foi 0,7 mmol/g contra 1,8 mmol/g. Na biossorção binária a captação de íons Pb (II) manteve o percentual de remoção mesmo em soluções com elevadas concentrações de íons Cu (II); o contrário não foi observado para o Pb(II), indicando que íons Pb (II) interferem mais na captação de íons Cu (II). Para o estudo do equilíbrio monocomponente foram utilizados os modelos de Langmuir e Freundlich; para o sistema binário, o Langmuir competitivo, Langmuir modificado, Langmuir-Freundlich e Freundlich estendido. Os modelos não foram conclusivos, porém elucidaram aspectos relacionados ao mecanismo, apresentando alto grau de dispersão entre a captação experimental e as teóricas. / Brown seaweeds from the genus Sargassum are widely studied for use as potential candidates for biosorption purposes, particularly in the treatment of heavy-metals contaminated effluents. The cellular structure of this seaweed presents charged molecules, such as alginic acid, able to attract and recover metal cation ions. The objective of this work was to study the uptake capacity of copper and lead by the seaweed Sargassum, through kinetic and isotherm studies with the help of kinetic and isotherm models for monocomponent and binary solutions. Equilibrium uptake was reached in 30 minutes and the kinetic behavior of the process followed a second-order model. In monocomponent systems, at 10 mg/L metal concentration, equilibrium uptake indicated a recovery of 0.06 mmol Cu(II)/g biomass and 0.02mmol/g Pb(II)/g biomass. When a 50 mg/L solution was used, the individual uptake was equal to 0.37 mmol Cu(II)/g biomass and 0.11 mmol Pb(II)/g biomass. Uptake was markedly reduced by the presence of the second metal in solution indicating the interference in biosorption in a multi-ion solution. Values of qmax for Pb(II) in the binary system was equal to 0.6 mmol/g biomass, against 1.2 mmol/g biomass in the monocomponent situation; for Cu(II) the uptake was equal to 0.7 mmol/g biomass against 1.8 mmol/g biomass, in the monocomponent solution. In the binary solution, Pb(II) uptake kept the same percent removal, even in the presence of high concentrations of Cu(II); an opposite behavior was observed for Cu(II), indicating that Pb(II) interfere in the uptake of Cu(II) more than the opposite situation. In the monocomponent equilibrium models such as Langmuir and Freundlich were used to fit experimental data. In binary systems, Competitive Langmuir, Modified Langmuir, Langmuir-Freundlich and Extended Freundlich Extented were used. All the models were not conclusive to fit experimental results, however they contributed for a better understanding of the mechanism involved in biosorption, because a high level of dispersion between actual biosorption and theoretical prediction was observed.
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Optimization of levels of seaweed japonica saccharine and chenopodium quinoa wild in developing cereal bar / OtimizaÃÃo dos teores de alga Saccharina japÃnica E Chenopodium quinoa Wild no desenvolvimento de barra de cereais

Ana LÃvia Brasil Silva 28 September 2015 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Seaweed japonica saccharine, popularly known as "Kombu" is a food rich in protein, fiber and micronutrients. This algae has antioxidant properties, anti-viral, anti-tumor, anti-inflammatory and hypoglycemic. Quinoa (Chenopodium quinoa Willd) is considered a pseudocereal whose main characteristic is the quality of its protein and is recognized by the World Health Organization (WHO) as an ideal food for its nutritional composition is higher than most cereals. The addition of these two ingredients in salt cereal bar formulation can add greater nutritional value to this product, which has shown an increasing consumption in recent years. The study aimed to prepare savory cereal bars added the saccharine japonica algae in different concentrations (2, 4, 6, 8, 10%) and quinoa (1, 2, 3, 4, and 5%), through the use of design central composite (DCC). One of the formulations of the cereal bars was selected to study storage stability, with respect to acidity and moisture and microbiological analysis, and sensory parameters at times 0, 30, 60 and 90 days. In the development of cereal bars, the formulations examined had ash contents of 4.46% to 8.04% (Formulations 9 and 4, respectively), fat 2.8% to 4.61% (Formulations 3 and 5, respectively), and protein 14.2% to 19.19% (Formulations 1 and 10, respectively). The Maoria bars showed sensory acceptance corresponding to "like slightly to like a lot," and had satisfactory results for microbiological analyzes. The formulation 5, added with 2% and 3% seaweed quinoa, achieved the best results concerning the nutritional and sensory quality, thus has been selected for the study of storage stability. The moisture and acidity remained stable after 90 days of storage, similar results were observed for the microbiological quality. According to sesorial analysis, the number 5 cereal bar is framed in sensory acceptance zone in category "like moderately" to "enjoyed". Therefore, it was concluded that the developed cereal bars can become an option for many types of diet or for those seeking a healthier lifestyle, it presented high protein and low fat, as well as showing good sensory acceptance. / A alga Saccharina japonica, conhecida popularmente como âKombuâ à um alimento rico em proteÃna, fibra e micronutrientes. Esta alga apresenta propriedade antioxidante, antiviral, antitumoral, anti-inflamatÃria e hipoglicÃmica. A quinoa (Chenopodium quinoa Willd) à considerada um pseudocereal que tem como principal caracterÃstica a qualidade de sua proteÃna, sendo reconhecida pela OrganizaÃÃo Mundial de SaÃde (OMS) como um alimento ideal, por sua composiÃÃo nutricional ser superior à maioria dos cereais. A adiÃÃo desses dois ingredientes na formulaÃÃo de barra de cereais salgada poderà agregar um maior valor nutricional a esse produto, que vem apresentando um crescente consumo nos Ãltimos anos. O trabalho teve como objetivo elaborar barras de cereais salgadas adicionadas da alga Saccharina japÃnica em diferentes concentraÃÃes (2, 4, 6, 8, 10%) e de quinoa (1, 2, 3, 4, e 5%), por meio do uso do Delineamento Composto Central Rotacional (DCCR). Uma das formulaÃÃes das barras de cereal foi selecionada para o estudo de estabilidade ao armazenamento, quanto Ãs anÃlises de acidez e umidade e aos parÃmetros microbiolÃgicos e sensoriais, nos tempos 0, 30, 60 e 90 dias. No desenvolvimento das barras de cereal, as formulaÃÃes analisadas apresentaram teores de cinzas de 4,46% a 8,04% (FormulaÃÃes 9 e 4, respectivamente), gordura de 2,8% a 4,61% (FormulaÃÃes 5 e 3, respectivamente), e proteÃna de 14,2% a 19,19% (FormulaÃÃes 1 e 10, respectivamente). A maoria das barras apresentou aceitaÃÃo sensorial correspondente a âgostei ligeiramente a gostei muitoâ, bem como tiveram resultados satisfatÃrios para as anÃlises microbiolÃgicas. A formulaÃÃo 5, adicionada com 2% de alga e 3% de quinoa, obteve os melhores resultados referentes à qualidade nutricional e sensorial, desta maneira foi selecionada para o estudo de estabilidade ao armazenamento. Os teores de umidade e de acidez mantiveram-se estÃveis apÃs 90 dias de estocagem, resultado semelhante foi observado para a qualidade microbiolÃgica. De acordo com as anÃlises sesorial, a barra de cereal de nÃmero 5 se enquadrou na zona de aceitaÃÃo sensorial na categoria âgostei moderadamenteâ a âgostei muitoâ. Portanto, concluiu-se que as barras de cereais desenvolvidas podem se tornar uma opÃÃo para diversos tipos de dieta ou para quem procura uma vida saudÃvel, pois apresentou elevado teor de proteÃnas e baixo teor de gordura, alÃm de apresentar boa aceitaÃÃo sensorial.
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Filogenia de Porphyra spp. (Rhodophyta): sequenciamento do gene nuclear para o RNA da subunidade pequena do ribossomo (rDNA 18S) e estudos morfológicos da fase Conchocelis / Phylogene of Porphyra spp (Rhodophyta): sequencing of the nuclear gene coding for the RNA from the small subunity of the ribosome (18S rDNA) and morphological studies of the Conchocelis phase

Mariana Cabral de Oliveira 15 December 1993 (has links)
O gênero Porphyra (Rhodophyta) apresenta uma considerável importância econômica, sendo extensivamente cultivado e consumido como alimento. O gênero é representado por mais de 70 espécies e apresenta ampla distribuição geográfica, desde regiões tropicais até polares. Sua taxonomia, baseada em poucos caracteres da fase macroscópica do seu ciclo de vida, é ainda bastante problemática. Para tentar entender melhor a taxonomia e a história evolutiva de Porphyra foram utilizadas metodologias de biologia molecular e características da fase conchocelis do ciclo de vida. Verificou-se que caracteres da fase microscópica podem ser utilizados para complementar os conhecimentos taxonômicos tradicionais. Para tentar elucidar a posição filogenética do gênero Porphyra na divisão Rhodophyta e, dentro do gênero, entre espécies do Atlântico, o gene nuclear que codifica para o RNA ribossomal da subunidade pequena do ribossomo (rDNA 18S) foi amplificado através de PCR, clonado e completamente sequenciado. Foram utilizadas três espécies de Porphyra da Nova Escócia (Canadá) e duas de São Paulo (Brasil). As sequências obtidas foram alinhadas com as de alguns eucariontes e de outras algas vermelhas, incluindo uma sequência publicada de \"Porphyra umbilicalis\" da França. As árvores filogenéticas foram construídas através dos métodos de parcimônia, distancia e máxima verossimilhança. As analises mostraram que o gênero Porphyra é monofilético para as cinco espécies estudadas e constitui um dos ramos mais antigos dentro das algas vermelhas já analisados. O gênero Porphyra, subclasse Bangiophycidae, apresentou uma diferença substancial em relação aos gêneros da subclasse Florrideophycidae, sustentando assim, a divisão de Rhodophyta em duas subclasses pela taxonomia tradicional. Entre os eucariontes, Porphyra divergiu ao mesmo tempo que o nuclemorfo de Cryptomonas. O alto grau de divergência genética encontrada entre espécies de Porphyra, além de indicações do registo fóssil, na literatura, sugerem que o gênero é bastante primitivo dentro das algas vermelhas. Surpreendentemente, a sequência publicada para \"Porphyra umbilicalis\" apresentou mais de 99% de identidade com uma espécie de Palmaria que pertence à subclasse Florideophycidae; neste caso, a biologia molecular serviu para comprovar a identificação errônea do exemplar cuja sequência foi publicada. Durante a análise filogenética, verificou-se a ocorrência de um intron do grupo ICI nos genes rDNA 18S de Porphyra spiralis var. amplifolia. Esse intron ocorre na mesma posição que os introns do grupo IC1 nos rDNA 18S dos fungos Pneumocystis carinii, Protomyces inouyei e da alga verde Chlorella ellipsoidea, e apresenta identidade de sequências nos domínios P1 e P2, fora da região conservada, com o intron de Pn. Carinii. Três variantes, diferindo do tamanho da seqüencia do domínio P1, foram observados em três populações com distribuição geográfica diferente. O variante maior pode se auto-processar (\"self-splice\") in vitro. Quadros abertos de leitura estão presentes nos introns, mas não correspondem a nenhum gene conhecido. Introns estão presentes no rDNA 18S de outras espécies de Porphyra, que também podem apresentar variantes do rDNA 18S sem introns / The red algas genus Porphyra has considerable economic importance, and some species are extensively cultivated for human food. The genus is represented by more than 70 species, and occurs worldwide. Its taxonomy, based mainly on morphological characters of the macroscopic phase of its life-cycle is still unsettled. Alternatives to try to understand better the taxonomy and evolutive history of the genus were ascertained. It was verified that characters of the microscopic, filamentous phase, of the life-cycle of Porphyra may be used to complement the traditional taxonomic studies. To try to elucidate the phylogenetic position of Porphyra relative to the other red algae, and within the genus, among isolates from different locations, nuclear-encoded small-subunit ribosomal RNA genes (18S rDNAs) were PCR-amplified, cloned and completely sequenced. Three species of Porphyra from Nova Scotia and two species from Brasil were aligned with 18S sequences of other eukaryotes, including one published sequence of \"Porphyra umbilicalis\" from France. Phylogenetic trees were constructed by parsimony, distance and maximum-likelihood procedures. Analysis of our data revealed that these Porphyra species represented one of the deepest branches so far discovered within red algae. There was a great degree of primary sequence difference between Porphyra (subclass Bangiophycidae), and the other red algae belonging to the subclasses Florideophycidae. These results support the division of red algae into two subclasses by traditional taxonomy. Among eukaryotes Porphyra diverges at the same point as the Cryptomonas nucleomorph. The great among of sequence divergence, and the fossil record suggest that Porphyra, my indeed, be a very primitive red alga. Surprisingly, the 18S RNA sequence of the French \"Porphyra umbilicalis\" does not fit in our Porphyra category; instead, it has more than 99% identity with a species of Palmaria belonging to the subclass Florideophycidae. Therefore it was concluded that \"P. umbilicalis\" with the published sequence was actually a Palmaria palmate that was misidentified. During the phylogenetic analysis it was found that a group IC1 intron occurs in nuclear 18S rRNA genes of Porphyra spiralis var. amplifolia. This intron occurs at the same position of the group IC1 introns in 18S rDNAs of the fungus Pneumocystis carinii, Protomyces inouyei and the green alga Chlorella ellipsoidea, and shares primary-structural identity with the Pn. Carinii intron in domains P1 and P2, outside the conserved core. Three size-variants, differing in amount of optimal sequence in P1, exist and are differentially distributed in geographically distinct populations. The largest variant can self-splice in vitro. Open reading frames are present, but do correspond to known genes. Introns are present in the 18S rDNAs of several other Porphyra species, that may also have intronless rDNA copies
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Growth, nodulation and yield responces of promiscuous and specific-nodulation soybean cultivars to rhizobium inoculation and seaweed extract

Raofa, Tshepo Prince January 2021 (has links)
Thesis (M.Sc. (Agronomy)) -- University of Limpopo, 2021 / Soybean (Glycine max L.) is one of the valuable leguminous crops with grain used for human consumption, livestock feeding, bio-fuel (bio-diesel) production, vegetable oil and is a protein resource. The crop also fixes atmospheric nitrogen. The study aimed to evaluate the performance of two soybean varieties to a combination of inoculation and seaweed extract. The research trial was conducted at Syferkuil farm during 2017/2018 summer season in which two soybean varieties (TGx 1937-1F promiscuous) and (PAN 1583R specific-nodulating) were evaluated for their growth, nodulation and yield responses to rhizobium inoculation and seaweed extract (0 % rate (0ml/12L), 50 % rate (30ml/12L) and 100 % (60ml/12L). The research trial was laid out as a split-split plot arrangement fitted in RCBD with four replications. Inoculation significantly influenced grain yield at P≤0.05, seed nutrient content and total above-ground biomass, except for seed potassium. No inoculation significantly achieved higher primary branches per plant at P≤0.05, pod number per plant, stem diameter (P≤0.05), grain yield (P≤0.05), harvest index and total above-ground biomass at P≤0.001. The variety TGx 1937-1F had significantly (P≤0.001) higher nodule number per plant, effective nodules per plant, nodule dry weight, dried shoot biomass, leaf number per plant, pod number per plant, primary branches per plant, stem diameter, plant height, leaf chlorophyll content, total above-ground biomass, grain yield and seed iron (Fe) content. Application of full rate seaweed extract significantly (P≤0.001) increased primary branches per plant, stem diameter, leaf number per plant, plant height, shelling percentage, total above-ground biomass, grain yield, and seed content of calcium (Ca), potassium, magnesium (Mg), manganese (Mn) and sodium (Na) all at P≤0.05. Seaweed extract rate at 0 % obtained the highest harvest index (P≤0.001). Inoculation and variety TGx 1937-1F interaction exhibited a significant increase on leaf number per plant at P≤0.001, primary branches per plant at P≤0.001 and plant height at P≤0.001. Variety TGx 1937-1F, without inoculation, obtained significantly higher pod number per plant (P≤0.001), stem diameter at P≤0.001, grain yield at P≤0.05 and total above-ground biomass at P≤0.001. Variety PAN 1583R, without inoculation, obtained significantly higher harvest index and shelling percentage at P≤0.001. Interaction of vi inoculation and seaweed extract showed that no inoculation × 100 % rate of seaweed extract significantly (P≤0.001) increased primary branches per plant, leaf number per plant, stem diameter, pod number per plant and plant height. Interaction of inoculation × 100 % rate of seaweed extract increased grain yield (P≤0.001) and total above-ground biomass at P≤0.001. Inoculation × 50 % rate of seaweed extract interaction increased shelling percentage at P≤0.001. No inoculation × 0 % rate of seaweed extract interaction obtained significantly higher harvest index (P≤0.001). Interaction of variety and seaweed extract showed that variety TGx 1937-1F × 100 % rate of seaweed extract significantly increased primary branches per plant (P≤0.001), pod number per plant at P≤0.001, grain yield at P≤0.001 and total above-ground biomass at P≤0.001. The variety TGx 1937-1F × 50 % rate of seaweed extract significantly raised the size of stem diameter (P≤0.01) and plant height (P≤0.001). Three-way interactive effects of inoculation × variety TGx 1937-1F × 100 % rate of seaweed extract obtained significantly higher number of shelling percentage at P≤0.001, leaf number per plant at P≤0.05 and primary branches per plant at P≤0.001. Interaction of no inoculation × variety TGx 1937-1F × 100 % rate of seaweed extract obtained significantly high pod number per plant at P≤0.001, grain yield at P≤0.05, total above-ground biomass at P≤0.001 and plant height at P≤0.001. No inoculation × PAN 1583R × 100 % rate of seaweed extract interaction had a higher harvest index at P≤0.001. The study showed that inoculation, seaweed extract, or their combination generally enhanced seed nutrient content, especially in variety TGx 1937-1F. The study further showed that promiscuous soybean (TGx 1937-1F) had higher grain yield, under stressful growing conditions as compared to PAN 1583R variety. This implies that soybean variety TGx 1937-1F, with 50 % or 100 % application rate of seaweed extract could be recommended to smallholder farmers. Key words: Soybean, inoculation, seaweed extract, phenological development, growth, nodulation, grain yield and seed nutrient content. / National Research Foundation (NRF)

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