No description available.

Lemnalol (8-isopropyl-5-methyl-4-methylene-decahydro-1, 5-cyclo-naphthalen- 3-ol) is a natural compound isolated from the marine soft coral Lemnalia cervicorni. In the present study, we focused to determine whether lemnalol has in vivo antinociceptive and anti-inflammatory effects on carrageenan-induced rat paw edema and the hyperalgesia model using the thermal hyperalgesia test, paw edema assay, and histological examination. Furthermore, we also explored the possible cellular mechanisms of lemnalol on carrageenan-induced inflammatory responses by immunohistochemistry. The present results show that both systemic and central administration of lemnalol significantly inhibits carrageenan-evoked thermal hyperalgesia behavior. Moreover, intramuscular injection of lemnalol also significantly decreases paw edema and improves the inflammatory status of the tissues with reduced neutrophil infiltration. From behavioral and immunohistological observations, we found that lemnalol exerts its anti-inflammatory and analgesic effects on carrageenan-induced inflammatory responses; the cellular mechanisms of these effects involved the inhibition of elevated inflammatory mediators, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), vascular endothelial cell growth factor (VEGF), tumor necrosis factor-£\ (TNF-£\), and deletion of phosphatase and tensin homologues on chromosome 10 (PTEN). Since 1962, the carrageenan-induced rat model of inflammation has been widely used as an animal model to investigate inflammatory mechanisms and anti-inflammatory activity of drugs and has been fully characterized. However, the use of rats as an animal model has certain limitations such as those associated with breeding, economy, efficiency, and higher dosage. Recently, many studies have demonstrated zebrafish (Danio rerio) to be a valuable animal model for the investigation of bioactive compounds and molecular mechanisms of various diseases. In the present study, we attempted to establish an inflammatory animal model in zebrafish. Our research results showed that intraperitoneal (i.p.) administration of carrageenan significantly increased body edema and caused death of zebrafish resulting in a decrease in the cumulative survival rate. These effects were significantly inhibited by i.p. administration of methylprednisolone. Immunohistochemical observations revealed i.p. carrageenan-induced upregulation of iNOS, heat shock protein 25 (Hsp25), heat shock protein 90 (Hsp90), and PTEN; however, heat shock protein 70 (Hsp70) was observed to be downregulated. The present study provides a new in vivo inflammatory model for the screening of small volumes of drugs or compounds.

No description available.

RESUMO Cap.2 Os procedimentos para a quantificação de carragenanas envolvem geralmente secagens da alga, seguida de lavagens, tratamento alcalino, extrações aquosas ou em soluções levemente alcalinas, e separação da carragenana dos resíduos. Os resultados obtidos são muito influenciados pelos diferentes métodos envolvidos e equipamentos utilizados. Esse trabalho tem como objetivo padronizar a técnica de extração de Kappaphycus alvarezii (Doty) Doty, cultivado em Ubatuba, SP, visando maximizar o teor final da carragenana obtida. Os melhores teores foram obtidos em algas com tratamento alcalino (hidróxido de potássio) a frio, seguido de tratamento a quente, na concentração de 6%, à temperatura de 80ºC, durante 2 horas, que facilitaram a filtração posterior. A proporção 5g de alga tratada em solução alcalina a frio, em 400 mL de água para extração foi estabelecida e um filtro de nylon foi escolhido como o mais eficiente para a separação de carragenana. RESUMO Cap. 3 Carragenanas são hidrocolóides comercialmente importantes por suas características como agentes gelificante e estabilizante. Apesar do seu teor ser de grande interesse, os estudos publicados apresentam amplas variações. Esse trabalho tem como objetivo analisar o teor de carragenanas e possíveis variações sazonais em Kappaphycus alvarezii (Doty) Doty, cultivado em Ubatuba, SP, entre 1999 e 2000. Foram estudados os tetrasporófitos marrom, verde e vermelho e uma linhagem derivada de tetrásporos. Os resultados foram comparados com Hypnea musciformis(Wulfen) Lamouroux, proveniente de Ubatuba, e amostras comerciais de Kappaphycus spp. Os maiores teores foram obtidos para linhagem derivada de tetrásporos e amostras comerciais, que apresentaram valores muito próximos. Os tetrasporófitos marrom, verde e vermelho apresentaram teores mais baixos e semelhantes entre si. Observou-se sazonalidade entre os teores das 4 linhagens de K. alvarezii, que se correlacionaram negativamente com as taxas de crescimento. Carragenanas de H. musciformis apresentaram os menores teores quando comparadas com as outras amostras analisadas. RESUMO Cap. 4 A força do gel e a caracterização química (conteúdo de sulfato e 3,6 anidro-Dgalactose)são parâmetros de grande interesse para avaliar a qualidade da carragenana. Esse trabalho tem como objetivo analisar e comparar a força do gel e o conteúdo de 6-sulfato e de 3,6-anidro-D-galactose das carragenanas extraídas de Kappaphycus alvarezii (Doty) Doty, cultivados em Ubatuba, SP, no ano de 2000. Esses parâmetros foram avaliados para amostras de carragenanas com diferentes tratamentos anteriores à extração (sem nenhum tratamento alcalino, com tratamento alcalino a frio, com tratamento alcalino a quente e com tratamento alcalino a frio seguido de quente). As carragenanas extraídas de algas com tratamento alcalino a frio seguido de quente apresentaram géis de melhor qualidade, com maior conteúdo de 3,6 anidro-D-galactose e força do gel. Foram analisadas também carragenanas dos tetrasporófitos marrom, verde e vermelho e uma linhagem derivada de tetrásporos. Essa última apresentou os melhores resultados, quando comparada às demais. Para as análises de força do gel foram utilizadas ainda amostras de Hypnea musciformes (Wulfen) Lamouroux e amostras comerciais de carragenana semirefinada, que apresentaram valores menores quando comparadas àquelas de K. alvarezii. Observaram-se, em amostras comerciais de Kappaphycus spp. e da linhagem derivada de tetrásporos, valores de força do gel aproximados. / ABSTRACT Cap.2 Procedures for the quantification of carrageenans generally involve drying of seaweed, followed by washing, alkali treatment, extraction in water or in lightly alkaline solutions, and separation of the carrageenan from the residues. Obtained results depend mostly on the various methods involved and equipment utilized. This paper was designated with the purpose of standardizing the extraction process of the Kappaphycus alvarezii (Doty) Doty, farmed in Ubatuba, SP, so as to maximize the final yield of the extracted carrageenan. Best results were obtained with algae under cold alkali treatment (potassium hydroxide), followed by hot treatment in 6% concentration at a temperature of 80oC for two hours, which made the later filtering easier. A proportion of 5g of the seaweed, treated in cold alkaline solution in 400mL of water, was established for the extration. A nylon filter was selected as the most efficient for the carrageenan\'s separation. ABSTRACT Cap. 3 Carrageenans are commercially important hydrocolloids, because of their characteristics as gelling and stabilizing agents. Their yield is regarded with great interest, but nevertheless, published studies show wide variations. The purpose of this paper is to analyze and compare carrageenan yields and their possible seasonal variations in Kappaphycus alvarezii (Doty) Doty farmed in Ubatuba, SP, between 1999 and 2000. Brown, green and red tetrasporophytes were studied, as was also, a strain derived from tetraspores. Results were compared with Hypnea musciformis (Wulfen)Lamouroux from Ubatuba and with commercial samples of Kappaphycus spp. Highest yields were obtained from the strain derived from tetraspores and from the commercial samples, which produced very similar values. Brown, green and red tetrasporophytes produced lower yields, with similar values among itselves. Seasonality was observed among the yields of the 4 strains of K. alvarezii, which showed negative correlation with the growth rates. Carrageenans of H. musciformis showed lowest yields as compared with other analyzed samples. ABSTRACT Cap. 4 Gel strength and chemical characteristics (sulphate and 3,6 anhydro-Dgalactose contents) are outstanding parameters for the evaluation of the carrageenan quality. The purpose of this paper is to analyze and compare gel strength and 6-sulphate and 3,6 anhydro-D-galactose contents of the carrageenan extracted from Kappaphycus alvarezii (Doty) Doty farmed in Ubatuba, SP, in 2000. Those parameters were evaluated for carrageenan samples submitted to different treatment carried out previously to the extraction (no alkali treatment, cold alkali treatment, hot alkali treatment and cold alkali treatment followed by hot). The carrageenan extracted from seaweed submitted to cold alkali treatment followed by hot produced the best quality gels, with the highest 3,6 anhydro-D-galactose content and gel strength. Carrageenans of brown, green and red tetrasporophytes as well as of a strain derived from tetraspores, were also analysed. Best results were obtained from the strain derived from tetraspores as compared with the others. Samples of Hypnea musciformes (Wulfen)Lamouroux were also utilized for the gel strength analysis, as well as commercial samples of semi-refined carrageenan, which presented lower values as compared to those of the K. alvarezii. Similar values of gel strength were observed in the commercial samples of Kappaphycus spp. and in the strain derived from tetraspores.

Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Food Science." Includes bibliographical references (p. 76-80).

RESUMO Cap.2 Os procedimentos para a quantificação de carragenanas envolvem geralmente secagens da alga, seguida de lavagens, tratamento alcalino, extrações aquosas ou em soluções levemente alcalinas, e separação da carragenana dos resíduos. Os resultados obtidos são muito influenciados pelos diferentes métodos envolvidos e equipamentos utilizados. Esse trabalho tem como objetivo padronizar a técnica de extração de Kappaphycus alvarezii (Doty) Doty, cultivado em Ubatuba, SP, visando maximizar o teor final da carragenana obtida. Os melhores teores foram obtidos em algas com tratamento alcalino (hidróxido de potássio) a frio, seguido de tratamento a quente, na concentração de 6%, à temperatura de 80ºC, durante 2 horas, que facilitaram a filtração posterior. A proporção 5g de alga tratada em solução alcalina a frio, em 400 mL de água para extração foi estabelecida e um filtro de nylon foi escolhido como o mais eficiente para a separação de carragenana. RESUMO Cap. 3 Carragenanas são hidrocolóides comercialmente importantes por suas características como agentes gelificante e estabilizante. Apesar do seu teor ser de grande interesse, os estudos publicados apresentam amplas variações. Esse trabalho tem como objetivo analisar o teor de carragenanas e possíveis variações sazonais em Kappaphycus alvarezii (Doty) Doty, cultivado em Ubatuba, SP, entre 1999 e 2000. Foram estudados os tetrasporófitos marrom, verde e vermelho e uma linhagem derivada de tetrásporos. Os resultados foram comparados com Hypnea musciformis(Wulfen) Lamouroux, proveniente de Ubatuba, e amostras comerciais de Kappaphycus spp. Os maiores teores foram obtidos para linhagem derivada de tetrásporos e amostras comerciais, que apresentaram valores muito próximos. Os tetrasporófitos marrom, verde e vermelho apresentaram teores mais baixos e semelhantes entre si. Observou-se sazonalidade entre os teores das 4 linhagens de K. alvarezii, que se correlacionaram negativamente com as taxas de crescimento. Carragenanas de H. musciformis apresentaram os menores teores quando comparadas com as outras amostras analisadas. RESUMO Cap. 4 A força do gel e a caracterização química (conteúdo de sulfato e 3,6 anidro-Dgalactose)são parâmetros de grande interesse para avaliar a qualidade da carragenana. Esse trabalho tem como objetivo analisar e comparar a força do gel e o conteúdo de 6-sulfato e de 3,6-anidro-D-galactose das carragenanas extraídas de Kappaphycus alvarezii (Doty) Doty, cultivados em Ubatuba, SP, no ano de 2000. Esses parâmetros foram avaliados para amostras de carragenanas com diferentes tratamentos anteriores à extração (sem nenhum tratamento alcalino, com tratamento alcalino a frio, com tratamento alcalino a quente e com tratamento alcalino a frio seguido de quente). As carragenanas extraídas de algas com tratamento alcalino a frio seguido de quente apresentaram géis de melhor qualidade, com maior conteúdo de 3,6 anidro-D-galactose e força do gel. Foram analisadas também carragenanas dos tetrasporófitos marrom, verde e vermelho e uma linhagem derivada de tetrásporos. Essa última apresentou os melhores resultados, quando comparada às demais. Para as análises de força do gel foram utilizadas ainda amostras de Hypnea musciformes (Wulfen) Lamouroux e amostras comerciais de carragenana semirefinada, que apresentaram valores menores quando comparadas àquelas de K. alvarezii. Observaram-se, em amostras comerciais de Kappaphycus spp. e da linhagem derivada de tetrásporos, valores de força do gel aproximados. / ABSTRACT Cap.2 Procedures for the quantification of carrageenans generally involve drying of seaweed, followed by washing, alkali treatment, extraction in water or in lightly alkaline solutions, and separation of the carrageenan from the residues. Obtained results depend mostly on the various methods involved and equipment utilized. This paper was designated with the purpose of standardizing the extraction process of the Kappaphycus alvarezii (Doty) Doty, farmed in Ubatuba, SP, so as to maximize the final yield of the extracted carrageenan. Best results were obtained with algae under cold alkali treatment (potassium hydroxide), followed by hot treatment in 6% concentration at a temperature of 80oC for two hours, which made the later filtering easier. A proportion of 5g of the seaweed, treated in cold alkaline solution in 400mL of water, was established for the extration. A nylon filter was selected as the most efficient for the carrageenan\'s separation. ABSTRACT Cap. 3 Carrageenans are commercially important hydrocolloids, because of their characteristics as gelling and stabilizing agents. Their yield is regarded with great interest, but nevertheless, published studies show wide variations. The purpose of this paper is to analyze and compare carrageenan yields and their possible seasonal variations in Kappaphycus alvarezii (Doty) Doty farmed in Ubatuba, SP, between 1999 and 2000. Brown, green and red tetrasporophytes were studied, as was also, a strain derived from tetraspores. Results were compared with Hypnea musciformis (Wulfen)Lamouroux from Ubatuba and with commercial samples of Kappaphycus spp. Highest yields were obtained from the strain derived from tetraspores and from the commercial samples, which produced very similar values. Brown, green and red tetrasporophytes produced lower yields, with similar values among itselves. Seasonality was observed among the yields of the 4 strains of K. alvarezii, which showed negative correlation with the growth rates. Carrageenans of H. musciformis showed lowest yields as compared with other analyzed samples. ABSTRACT Cap. 4 Gel strength and chemical characteristics (sulphate and 3,6 anhydro-Dgalactose contents) are outstanding parameters for the evaluation of the carrageenan quality. The purpose of this paper is to analyze and compare gel strength and 6-sulphate and 3,6 anhydro-D-galactose contents of the carrageenan extracted from Kappaphycus alvarezii (Doty) Doty farmed in Ubatuba, SP, in 2000. Those parameters were evaluated for carrageenan samples submitted to different treatment carried out previously to the extraction (no alkali treatment, cold alkali treatment, hot alkali treatment and cold alkali treatment followed by hot). The carrageenan extracted from seaweed submitted to cold alkali treatment followed by hot produced the best quality gels, with the highest 3,6 anhydro-D-galactose content and gel strength. Carrageenans of brown, green and red tetrasporophytes as well as of a strain derived from tetraspores, were also analysed. Best results were obtained from the strain derived from tetraspores as compared with the others. Samples of Hypnea musciformes (Wulfen)Lamouroux were also utilized for the gel strength analysis, as well as commercial samples of semi-refined carrageenan, which presented lower values as compared to those of the K. alvarezii. Similar values of gel strength were observed in the commercial samples of Kappaphycus spp. and in the strain derived from tetraspores.

Kappaphycus alvarezii (Doty) Doty ex P. C. Silva é uma alga vermelha comercialmente importante por ser a principal fonte de carragenana kappa, hidrocolóide utilizado como agente espessante e estabilizante em alimentos, fármacos e cosméticos. Devido à sua importância, é fundamental desenvolver bases tecnológicas visando sua maricultura sustentada e a seleção de linhagens mais produtivas com carragenanas de melhor qualidade. Esse trabalho teve como objetivos: 1. desenvolver a cultura de tecidos para a propagação de plantas matrizes, selecionar as melhores linhagens para cultivo in vitro e produzir novas linhagens; 2. testar a espécie como biofiltro em cultivos integrados com peixes e 3. analisar os efeitos de diferentes condições de cultivo no rendimento e na qualidade das carragenanas, segundo parâmetros comerciais. Para o primeiro objetivo, foram testadas cinco linhagens (tetrasporófitos marrom, verde e vermelho, gametófito feminino e linhagem “Edison de Paula", EP, selecionada a partir da germinação de tetrásporos) para definir o sistema experimental mais adequado para a micropropagação. Explantes da linhagem EP foram tratados com colchicina com a finalidade de induzir linhagens poliplóides. Essa linhagem foi selecionada por apresentar maior tolerância aos procedimentos de esterilização utilizados na cultura de tecidos. Apesar das altas taxas de indução de calos observadas em todas as linhagens, a regeneração de talos a partir dos calos (regeneração indireta) foi difícil. A regeneração de talos a partir dos explantes (regeneração direta) foi estimulada pela utilização de fitorreguladores e da colchicina. A contaminação dos cultivos por uma espécie filamentosa Acrochaetium no talo da linhagem EP foi inibida com a adição de 90 mM de glicerol. A formação de novas linhagens poliplóides através da utilização de colchicina não foi demonstrada. Os resultados indicaram que é possível utilizar a micropropagação através da produção de explantes para manutenção de um estoque de plantas matrizes de diferentes linhagens em laboratório. Para o segundo objetivo, o tetrasporófito marrom da espécie foi cultivado em tanques com água do mar e com efluente da criação de peixes da espécie Trachinotus carolinus (pampos) por 10 dias. As taxas de crescimento das algas cultivadas nos tanques foram mais baixas que às obtidas em cultivo no mar. Os valores máximos da taxa de remoção nos efluentes foram: NO3- = 18,2%; NO2- = 50,8%; NH4+ = 70,5% e PO43- =26,8%, nas condições testadas. Todas as plantas sobreviveram até o final do período experimental, mas apresentaram sinais de "ice-ice", doença associada ao estresse fisiológico. Diferenças entre os rendimentos de carragenana de algas cultivadas em água do mar ou em efluente de criação de peixes não foram significativas. Esses resultados demonstraram que é possível utilizar K. alvarezii como biofiltro de águas eutrofizadas derivadas da criação de peixes embora a espécie seja típica de águas oligotróficas. Para o terceiro objetivo, o gametófito feminino foi cultivado em balsas flutuantes segundo diferentes condições de cultivo (período de cultivo, profundidade e densidade do plantio). As carragenanas das plantas cultivadas nesses tratamentos foram extraídas e algumas propriedades foram determinadas. As taxas de crescimento variaram de 5,2 a 7,2% dia-1, com as maiores taxas obtidas em 28 dias de cultivo, em profundidade de 0 e 0,5 m e densidade do plantio de 12 e 8,4 plantas m-2. As condições de cultivo que forneceram melhor carragenana, segundo padrões comerciais foram: 45 dias de cultivo, na superfície, com densidade de 12 plantas m-2. Considerando que esse cultivo foi realizado na estação menos favorável do ano (inverno) para o crescimento das plantas, esses resultados indicam que o local onde a espécie foi introduzida é adequado para a implementação do cultivo comercial. Através dos resultados obtidos nesse trabalho, desejamos contribuir com a maricultura sustentável de uma espécie promissora no Brasil, com excelente potencial econômico reconhecido mundialmente, além de deixar algumas sugestões e propostas para novos estudos. / Kappaphycus alvarezii (Doty) Doty ex P. C. Silva is a red seaweed commercially important for being the main source of kappa carrageenan, hydrocolloid utilised as thickener and stabiliser in foods, medicaments and cosmetics. Due to its importance it is fundamental to develop technological bases on purpose of its sustainable mariculture and the selection of more productive strains with best qualities carrageenans. The objectives of this work were: 1. to develop the tissue culture for micropropagation of matrix plants, to select the better strains for in vitro culture and to produce new strains; 2. to test the species as biofilter in integrated cultivation with fishes and 3. to analyse the effects of different cultivation conditions in carrageenan yield and quality, according to commercial parameters. For the first objective, five strains (brown, green and red tetrasporophytes, female gametophyte and "Edison de Paula" strain, EP, selected from tetraspores progeny) were tested to define the experimental system suitable for micropropagation. Explants from EP strain were treated with colchicine with the aim of induce polyploid strains. This strain was selected by presenting high tolerance to sterilization procedures used in tissue culture. Despite the high rates of callus induction observed in all strains, thallus regeneration from callus (indirect regeneration) was difficult. Thallus regeneration from explants (direct regeneration) was stimulated by phytorregulators and colchicine. The culture contamination by a filamentous species Acrochaetium in the tallus of EP strain was inhibited with addition of 90 mM glycerol. The formation of polyploid strains by colchicine treatments was not proved. The results indicated that it is possible to use the micropropagation through the production of explants for maintaining matrix plants stocks from different strains in laboratory. For the second objective, the brown tetrasporophyte was cultivated in tanks with seawater and with effluents of the fish Trachinotus carolinus (pampos) rearing for 10 days. Growth rates of seaweeds cultivated in tanks was lower than those cultivated in the sea. The maximum values of removal rates from the effluents were: NO3- = 18.2%; NO2- = 50.8%; NH4+ = 70.5% and PO43- =26.8% in the conditions tested. All plants survived until the end of experimental period, but they presented signals of "ice-ice", disease associated to physiological stress. Differences between the carrageenan yields from plants cultivated in seawater and in effluents of fish rearing were not significant. These results showed that it was possible utilised the seaweed K. alvarezii as biofilter in effluents from fish rearing, although the species is typical of oligotrophic waters. For the third objective, the female gametophyte was cultivated from floating raft according to different cultivation conditions (i.e. cultivation period, depth and planting density). Carrageenan from the plants cultivated under these treatments was extracted and some properties were determined. Growth rates ranged from 5.2 to 7.2% day-1, with the higher rates obtained in 28 day cultivation period, at 0 and 0.5 m of depth and planting density of 12 and 8.4 plants m-2. The cultivation conditions that supplied the best carrageenan, according to commercial patterns were: 45 days of cultivation, in surface, with planting density of 12 plants m-2. Considering that this cultivation was conducted in the unfavourable season of the year (winter) for the growth of K. alvarezii, the results indicated that the site where the species was introduced is adequate to the implementation of commercial cultivation. Through the results obtained in this work, we wish to contribute with sustainable mariculture of a successful species in Brazil, with excellent economic potential recognised in all world, besides leave some suggestions and proposes for new studies.

A estimulação química das fibras aferentes nociceptivas através da injeção de diferentes substâncias álgicas vem sendo estudada em modelos de dor muscular em animais. A carragenina é um dos agentes que produz inflamação aguda e é freqüentemente utilizada em modelos de dor muscular. O nosso objetivo é aprofundar nossa compreensão e explorar em maior detalhe a participação das células gliais (astrócitos e microglia), de citocinas pró-inflamatórias, prostanóides e do óxido nítrico, após a indução de miosite aguda, correlacionando com modelos comportamentais nociceptivos. Para tanto, serão avaliadas as atividades dos mediadores, previamente descritos, na medula espinal dos ratos com e/ ou sem indução de miosite, através do método de Western blotting. Tais investigações poderão vir a ser uma abordagem totalmente inovadora para tentar entender quais são alguns dos mediadores envolvidos neste modelo de dor. Assim, os dados obtidos neste projeto poderão elucidar os mecanismos envolvidos na dor músculo-esquelética, a qual se enquadra nas patologias de difíceis tratamentos e de grande relevância clínica. / Chemical stimulation of nociceptive afferent fibers through the injection of different substances has been studied in different models of muscle pain in animals. Carrageenan is one of the agents that produce inflammation and is often used in models of muscle pain. Our goal is to explore in greater detail the involvement of glial cells (astrocytes and microglia), pro-inflammatory cytokines, prostanoids and nitric oxide after induction of acute myositis and correlate it with nociceptive behavioral models. It will be assessed the activity of these mediators in the spinal cord after induction of myositis in rats, using Western blotting assay. Such investigations may be a totally new approach to try to understand how some mediators are involved in this kind of pain. Thus, the data obtained in this project will elucidate the mechanisms involved in musculoskeletal pain, which are of difficult treatment and of great clinical relevance.

Les carraghénanes (Car) sont des polysaccharides linéaires sulfatés extraits d’algues rouges et sont très utilisés en tant qu’épaississants et gélifiant en industrie. Les rendements d’extraction ainsi que les propriétés physicochimiques de Car extraits de différentes espèces cultivées dans la baie de Cam Ranh au Vietnam ont été déterminés. Pour les variantes kappa et iota, les propriétés rhéologiques et de la microstructure en solution seuls ou en mélange à différentes concentrations en présence de CaCl2 ou de KCl. Leurs mélanges présentent une gélification thermique en deux étapes qui correspondent chacune aux gélifications du kappa et iota seuls. Cependant, pour les mélanges, l’élasticité du gel est nettement supérieure à la somme de celle des Car seuls. Des mesures en microscopie confocale et de turbidimétrie ont démontré que les gels obtenus avec le kappa étaient toujours plus turbides que ceux avec l’iota mais étaient moins turbides dans les mélanges. Au vus des résultats, un mécanisme de séparation de phase microscopique entre les deux Car semble très peu probable. Des mesures de FRAP (Recouvrance de Fluorescence Après Photo-blanchiment) ont permis de sonder la mobilité des chaînes de Car dans les gels pour les systèmes individuels ou les mélange. Dans tous les cas, il a été observée qu’une fraction des chaînes de Car reste mobile dans les gels. Cette fraction mobile varie de 25% à 75% selon le type de Car et le type/concentration en sel. Cette fraction n’est pas corrélée à la dureté du gel quelles que soient les conditions opératoires. De plus, il a été démontré que les chaines relarguées sont plus petites que la moyenne de l’échantillon initial. / Carrageenan (Car) is a polysaccharide extracted from red algae and is widely used as thickener, stabilizer and gelling agent in various products. Properties of Car extracted from different algae species cultured at Cam Ranh Bay in Vietnam were characterized. Kappa car extracted from K. alvarezii and iota Car from E.denticulatum were selected to study the rheological properties and the microstructure of individual and mixed car solutions in presence of CaCl2 and KCl. Mixtures showed a two-step gelation process with gelation temperatures that coincided with those of corresponding individual kappa and iota Car solutions. However, the stiffness of the mixed gels was much higher than the sum of the corresponding individual gels. Confocal laser scanning microscopy and turbidity measurements showed that the kappa Car gel was always more heterogeneous than the iota Car gel, but less in the mixture than in the individual system. The results show that microphase separation of iota and kappa Car in mixed gels is highly unlikely.The mobility of Car chains in individual gels of kappa and iota Car and their mixtures was determined using fluorescence recovery after photobleaching. Slow recovery was observed for the gels showing that a fraction of the Car chains remained mobile. The fraction of mobile chains in the gels varied between 25% and 75% depending on the type of Car and the type and concentration of salt. The fraction of mobile chains in gels was not correlated to the gel stiffness. These results were confirmed by the release of Car from gel fragments into excess solvent. It was found that released Car chains were smaller than the average size of the initial Car sample.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Dentre as espÃcies produtoras de carragenana a Hypnea musciformis à a bastante comum na costa do nordeste Brasileiro. Embora as propriedades da carragenana da H. musciformis sejam promissoras, suas populaÃÃes naturais sÃo geralmente insuficientes a pressÃo da colheita comercial. O cultivo tem sido uma saÃda para incrementar a produÃÃo mundial de algas. Desta forma, o presente trabalho se propÃs a avaliar o potencial para aquicultura da carragenÃfita Hypnea musciformis (Wulfen) j.v. lamour. (Gigartinales - Rhodophyta). Os experimentos foram realizados na praia de Flecheiras, no litoral do estado do CearÃ, Brasil. Foi avaliado o cultivo da H. musciformis em estruturas long-line, o cultivo foi realizado em diferentes Ãpocas do ano (2007) com comprimentos de substratos variados, em diferentes profundidades, sendo avaliado ainda o rendimento da carragenana produzida por algas cultivadas. As mudas cultivadas obtiveram os melhores ganhos de biomassa apÃs 30, 45 e 60 dias de cultivo, para os meses de setembro à novembro 325,7Â44,2g; 359,4Â51,8g e 411,2Â77,8g respectivamente, com taxa de crescimento diÃrio 6,246%; 0,218% e 0,224% respectivamente. Em relaÃÃo à profundidade de cultivo, as algas apresentaram maior ganho biomassa a 0.2 m de profundidade, com taxas de crescimento diÃrio de 5,38 %. Para o comprimento do substrato de cultivo as cordas com 0,8 m apresentaram os melhores resultados, 403,33 g e 616,33g para 30 e 60 dias de cultivo respectivamente. O rendimento de carragenana nÃo apresentou diferenÃas significativas, sendo 32,96 (%) para as algas cultivadas e 32,74 (%) para algas dos bancos naturais / Among the species producing the carrageenan Hypnea musciformis is quite common on the northeast coast of Brazil. Although the properties of carrageenan from H. musciformis are promising, their natural populations are generally insufficient pressure from commercial harvest. The crop has been a way to increase the world production of algae. The present study was to evaluate the potential for aquaculture of Hypnea musciformis (Wulfen) jv Lamour. (Gigartinales - Rhodophyta). The experiments were carried on the Flecheiras beach on coast of CearÃ, Brazil. We evaluated the cultivation of H. musciformis in long-line structures, with adjustments as a substrate for the cultivation of this species, the culture was grown in different seasons (2007) substrates with varying lengths at different depths, and rated the performance of the carrageenan produced by grown algae. Seedlings grown obtained the best gains in biomass after 30, 45 and 60 days of cultivation, for the months of September to November 325.7  44.2 g, 359.4  51.8 g and 411.2  77.8 g respectively with daily growth rate 6.246%, 0.218% and 0.224% respectively. In relation to the depth of cultivation, the algae had greater average biomass to 0.2 meters deep, with daily growth rates of 5.38%. For the length of the growth substrate the strings with 0.8 meters showed the best results, 403.33 g and 616.33 g for 30 and 60 days culture respectively. The yield of carrageenan did not show significant differences, 32.96 (%) for algae grown and 32.74 (%) for algae from natural beds