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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.
61

Efeitos antinociceptivo e anti-inflamatÃrio da lectina da alga marinha verde Caulerpa cupressoides no modelo de artrite induzida por zymosan na articulaÃÃo temporomandibular de ratos / Antinociceptive and anti-inflammatory effects of lectin green seaweed Caulerpa cupressoides in zymosan-induced arthritis model in the temporomandibular joint of rats

Renata Line da ConceiÃÃo Rivanor 31 January 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As algas marinhas sÃo fontes de compostos bioativos para a indÃstria farmacÃutica e dentre esses compostos destacamos as lectinas. O presente trabalho teve como objetivo investigar os efeitos antinociceptivo e anti-inflamatÃrio da lectina da alga marinha verde Caulerpa cupressoides (LCc) no modelo de artrite induzida por zymosan (Zy) na articulaÃÃo temporomandibular (ATM) de ratos. LCc foi extraÃda com tampÃo Tris-HCl 25 mM, pH 7,5 e isolada por cromatografia de troca iÃnica em coluna de DEAE-celulose. Nos ensaios de artrite induzida por Zy, ratos Wistar machos receberam LCc (0,1; 1 ou 10 mg/kg; i.v.) ou salina estÃril, 30 min antes da injeÃÃo intra-articular (i.art.) de Zy (2 mg/art., 40 ÂL) na ATM esquerda. Grupos controles receberam salina estÃril (40 ÂL; i.art.), indometacina (5 mg/kg; s.c) ou morfina (5 mg/kg, s.c.). Grupos de animais receberam LCc (10 mg/kg, i.v.) associada à mucina (100 mg/kg, i.v.), um aÃÃcar inibidor, e outro grupo recebeu somente mucina antes dos estÃmulos. Para analisar o envolvimento da via da HO-1 na artrite, os animais foram prÃ-tratados (3 mg/kg, s.c.) com um inibidor especÃfico do grupo heme (zinco protoporfirina IX â ZnPP IX). Finalmente, para avaliar se o efeito antinociceptivo de LCc estava envolvido na ativaÃÃo do sistema opioide, grupo de animais receberam uma injeÃÃo i.art. (10 &#956;g/art.;15 ÂL) de um antagonista de receptores opioides (naloxona), 35 min antes da injeÃÃo de Zy. ApÃs 5 min, os animais foram prÃ-tratados com LCc (10 mg/kg). A hipernocicepÃÃo mecÃnica foi medida utilizando o mÃtodo de Von Frey elÃtrico no tempo basal e 4 h apÃs a injeÃÃo de Zy. Na 6a hora, os animais foram eutanasiados e suas ATM lavadas para coleta do lavado sinovial e realizaÃÃo da contagem total de cÃlulas e dosagem de mieloperoxidase (MPO). Posteriormente, as ATM foram removidas para as anÃlises histolÃgicas e imunohistoquÃmica (TNF-&#945;, IL-1&#946; e HO-1), alÃm da dosagem de IL-1&#946; no tecido periarticular e gÃnglio trigeminal. O prÃ-tratamento com LCc (0,1, 1 ou 10 mg/kg; i.v.) reduziu significativamente a hipernocicepÃÃo induzida por Zy (81, 83 e 89,5%, respectivamente) e inibiu o influxo de leucÃcitos (77,3, 80,7 e 98,5%, respectivamente) comparado ao grupo Zy, sendo confirmada pela atividade de MPO. O aÃÃcar inibidor (mucina) nÃo foi capaz de inibir o efeito anti-inflamatÃrio e antinociceptivo de LCc na artrite induzida por Zy. Observamos que durante a anÃlise histolÃgica da ATM, os animais tratados com LCc apresentaram uma reduÃÃo significativa do influxo celular na membrana sinovial. AlÃm disso, LCc reduziu significativamente a produÃÃo de IL-1&#946; no tecido periarticular e a expressÃo de IL-1&#946;, TNF-&#945; e HO-1 na membrana sinovial durante o ensaio de imunohistoquÃmica. O tratamento com ZnPP IX nÃo foi capaz de inibir os efeitos de LCc, mostrando que sua aÃÃo antinociceptiva e anti-inflamatÃria nÃo ocorre pela via da HO-1. AlÃm disso, o tratamento com naloxona nÃo reverteu o efeito de LCc. Portanto, LCc apresentou efeito antinociceptivo e anti-inflamatÃrio no modelo de artrite induzida por Zy, reduzindo a produÃÃo de citocinas primÃrias (TNF-&#945; e IL-1&#946;), porÃm sua aÃÃo antinociceptiva nÃo ocorre pelo mecanismo opioide perifÃrico. / Seaweeds are sources of bioactive compounds for the pharmaceutical industry and among these compounds include the lectins. The present study aimed to investigate the effects antinociceptive and anti-inflammatory of the lectin of the green seaweed Caulerpa cupressoides (CcL) on model of zymosan-induced arthritis in the temporomandibular joint (TMJ) of rats. CcL was extracted with 25 mM Tris-HCl buffer pH 7.5 and isolated by ion exchange chromatography on DEAE-cellulose column. In tests of arthritis induced by Zy, male Wistar rats received CcL (0.1, 1 or 10 mg/kg, i.v.) or sterile saline, 30 min before the intra-articular (i.art.) injection of Zy (2 mg/art.; 40 &#956;L) into the left TMJ. Control groups received saline (40 &#956;L; i.art.), indomethacin (5 mg/kg, s.c.) or morphine (5 mg/kg, s.c.). Groups of animals received CcL (10 mg/kg; i.v.) associated with mucin (8 mg/kg; i.v.), a sugar inhibitor, and another group received only mucin before stimulus. To analyze the involvement of HO-1 pathway in arthritis, animals were pretreated (3 mg/kg, s.c.) with a specific inhibitor of heme (zinc protoporphyrin IX-ZnPP IX). Finally, to evaluate the analgesic effect of CcL in the activation of the opioid system, group of animals received an injection i.art. (10 &#956;g/art.; 15 ÂL) of the opioid receptor antagonist (naloxone), 35 min before injection of Zy. After 5 min, the animals were pretreated with CcL (10 mg/kg). Mechanical hypernociception was recorded before the i.art. injections of Zy or saline and after 4h. After 6 hour, the synovial fluid was collected to perform cell counting and myeloperoxidase (MPO) assay. Also, TMJ tissues were excised to perform histopathological, immunohistochemistry (TNF-&#945;, IL-1&#946; e HO-1) and cytokine assays (IL-1&#946;) in the periarticular tissue and trigeminal ganglion. Pretreatment with CcL (0.1, 1 or 10 mg/kg; i.v.) inhibited (p<0.05) the nociceptive response (81, 83, and 89.5%, respectively) and reduced the influx of leukocytes (77.3, 80.7 and 98.5%, respectively) compared to Zy group, as demonstrated by MPO activity. Sugar inhibitor (mucin) did not inhibit the anti-inflammatory and antinociceptive effect of CcL in arthritis induced by Zy. We observed that during the histological analysis of ATM, animals treated with CcL showed a significant reduction of cell influx in the synovial membrane. Furthermore, CcL significantly reduced the production of IL-1&#946; in the periarticular tissue and expression of IL-1&#946;, TNF-&#945; and HO-1 in the synovial membrane during immunohistochemistry assay. Treatment with ZnPP IX was not able to inhibit the effect CcL, indicating that its antinociceptive and anti-inflammatory action did not occur HO-1 pathway. In addition, treatment with naloxone did not reverse the effect of CcL. Therefore, CcL showed antinociceptive and anti-inflammatory effect on model of Zy-induced arthritis, reducing the production of primary cytokines (TNF-&#945; and IL-1&#946;), however its antinociceptive action did not occur by peripheral opioid mechanism.
62

CaracterizaÃÃo estrutural e atividade anti-inflamatÃria da lectina da alga marinha vermelha Bryothamnion triquetrum / Structural characterization and anti-inflammatory activity of the lectin from the red seaweed triquetrum Bryothamnion

Thais Pontes Carvalho Fontenelle 19 April 2012 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / A grande diversidade biolÃgica das algas marinhas e sua ocorrÃncia em praticamente todos os ambientes do planeta demonstram a importÃncia desses seres para os ecossistemas. Um deles à a extraÃÃo de biomolÃculas potencialmente ativa como as lectinas, que sÃo proteÃnas que tÃm sido alvo de pesquisas no mundo inteiro. Isso se deve à sua impressionante capacidade de ligar-se especificamente a carboidratos ou a substÃncias que os contÃm, propiciando um imenso campo de aplicaÃÃo biolÃgica. O objetivo deste trabalho foi produzir a lectina da alga marinha vermelha Bryothamnion triquetrum (Lec), avaliar sua estrutura secundÃria a partir de tÃcnicas espectroscÃpicas e investigar as suas propriedades anti-inflamatÃrias em camundongos. Primeiramente a lectina foi purificada por precipitaÃÃo com sulfato de amÃnio (0-60) e cromatografia de troca â iÃnica, sendo recolhido o primeiro pico (PI). Este pico foi selecionado atravÃs da atividade de hemaglutinaÃÃo obtendo assim a lectina pura a partir de Bryothamnion triquetrum, verificada por SDS-PAGE. A lectina foi analisada quanto a sua estrutura secundÃria por tÃcnicas espectroscÃpicas de dicroÃsmo circular, frente a extremos de pH (4,0 â 11,0) e comparada ao espectro da sua estrutura nativa, e fluorescÃncia frente a diferentes temperaturas que variaram de 25 a 75 em intervalo de 10Â. Na avaliaÃÃo das atividades biolÃgicas, grupos de animais foram submetidos ao prÃ-tratamento com a Lectina (1,5 e10mg/kg; i.p.) e indometacina (10mg/kg), 30 min antes do estÃmulo inflamatÃrio. A atividade anti-inflamatÃria em camundongos foi avaliada atravÃs dos ensaios de peritonite induzida por carragenina - Cg (500 &#956;g/cav) e de edema de pata induzidos por Cg (500 &#956;g/pata); dextrano (500 &#956;g/pata). Extremos do pH (4,0 e 11,0) nÃo alterou a estrutura secundÃria da proteÃna. Os dados de fluorescÃncia (280nm e 295nm), mostraram tambÃm uma estabilidade, alÃm da presenÃa de aminoÃcidos aromÃticos na sua estrutura. A Lectina inibiu a migraÃÃo celular na peritonite induzida por Cg e os edemas de pata induzidos por Cg e dextrano. Deste modo, conclui-se que a Lectina obtida do PI da DEAE de Bryothamnion triquetrum apresentou estrutura estÃvel em relaÃÃo a variaÃÃo de pH e temperatura. Em relaÃÃo Ãs propriedades biolÃgicas testadas, a Lectina apresentou efeitos anti-inflamatÃrios nos modelos empregados, podendo ser considerada uma molÃcula com potencial para estudos mais aprofundados de inflamaÃÃo. / The great biodiversity of seaweeds and their occurrence in almost all environments on the planet demonstrate the importance of such beings to ecosystems. One example is the extraction of potentially active biomolecules such as lectins, which are proteins that have been subject of research worldwide. This is due to its impressive ability to bind specifically to carbohydrates or substances containing them, providing an immense field of biological application. This work purpose was to produce lectin from the red seaweed Bryothamnion triquetrum (Lec), evaluate its secondary structure using spectroscopic techniques, and investigate their anti-inflammatory properties in mice. Initially, the lectin was purified by precipitation with ammonium sulfate (0-60) and ion exchange chromatography, and obtained the first peak (PI). This peak was selected by hemagglutination activity thus obtaining pure lectin from Bryothamnion triquetrum, verified by SDS-PAGE. The secondary structure of lectin was analyzed by circular dichroism spectroscopic techniques, against to pH extremes (4.0 to 11.0), and compared to the spectrum of its native structure, and fluorescence against different temperatures, ranging from 25 to 75Â, each 10 interval. In biological activities assessment, groups of animals were subjected to pretreatment with the lectin (1.5 and 10mg/kg, ip) and indomethacin (10mg/kg) 30 min before the inflammatory stimulus. The anti-inflammatory activity in mice was evaluated through the assays of peritonitis induced by carrageenan - Cg (500 &#956;g / cav) and paw edema induced by Cg (500 &#956;g / paw), and dextran (500 &#956;g / paw). Extremes of pH (4.0 and 11.0) did not alter the protein secondary structure. Fluorescence data (280nm and 295nm) also showed stability, and aromatic amino acids presence in their structure. Lectin inhibited cell migration in the induced peritonitis by Cg and induced paw edema by Cg and dextran. Thus, it is concluded that the lectin obtained from the Bryothamnion triquetrum DEAE PI shows stable structure related to pH and temperature variation. Regarding biological properties tested, the lectin showed anti-inflammatory effects in models used, and it can be considered a molecule with potential for further studies of inflammation.
63

Isolation, purification and partial characterization of the primary structure of a ficobiliproteÃna from the red marine alga Hypnea musciformis (Wulfen) Lamouroux / Isolamento, purificaÃÃo e caracterizaÃÃo parcial da estrutura primÃria de uma ficobiliproteÃna da alga marinha vermelha Hypnea musciformis (Wulfen) Lamouroux

Clareane Avelino Simplicio Nobre 06 February 2015 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Seaweeds are a rich reserve of substances with biotechnological interest, among these substances it is possible to highlight the phycobiliproteins. These molecules are water-soluble proteins covalently linked to pigments with linear tetrapyrrole structure called bilin, also known as accessory pigment. Thus, the phycobiliproteins form a complex named phycobilisomes, which is a primary structure of light-gathering, showing photosynthetic function. These structures are found in red and Cyanophyceae seaweed. Phycobiliproteins isolated and purified, when structuraly analised, present subunits characterized as alpha, beta and gamma. These proteins can be used as colorants and stabilizers for food, markers of biomolecules, antioxidants and anti-inflammatory agents. In view of the importance of these molecules, this work aimed to isolate, purify and determine the partial primary structure of the beta chain phycobiliprotein present in the red marine algae Hypnea musciformis. The phycobiliprotein (HMp) was isolated by precipitation of proteins with ammonium sulphate and purified by ion-exchange chromatography. The polyacrylamide gel electrophoresis revealed that the HMp has two chains around 20 kDa and 22 kDa. The 22 kDa chain was excised from the gel and digested with proteolytic enzyme trypsin. The peptides from digestion underwent fragmentation in mass spectrometer. The generated fragments were used for sequencing peptides and have identified in databases. Primers were designed to amplify the beta chain gene bhmp from the genomic DNA of the algae. The amplified gene was sequenced and the tool Phred/Phrap/Consed processed the raw data. The final gene sequence has been translated to obtain the partial primary structure of bHMp. The translation resulted in a sequence with 87 amino acid residues and HMp presented identity with various phycoerythrins of red algae. / As algas marinhas constituem uma rica reserva de substÃncia de interesse biotecnolÃgico, dentre essas substÃncias podemos destacar as ficobiliproteÃnas. Essas molÃculas sÃo proteÃnas solÃveis em Ãgua ligadas covalentemente a pigmentos com estrutura tetrapirrÃlica linear denominado bilina, tambÃm conhecido como pigmento acessÃrio. Dessa forma, as ficobiliproteÃnas formam um complexo denominado ficobilissomos, que constitui uma estrutura primordial de captaÃÃo de luz, apresentando funÃÃo fotossintÃtica. Essas estruturas sÃo encontradas nas algas marinhas vermelhas e cianofÃceas. FicobiliproteÃnas isoladas e purificadas, quando caracterizadas, apresentaram subunidades estruturais, como subunidades alfa, beta e gama. Quanto a suas aplicaÃÃes, essas proteÃnas foram utilizadas como corantes e estabilizantes de alimentos, marcadores de biomolÃculas, agentes antioxidantes e anti-inflamatÃrios. Tendo em vista a importÃncia destas molÃculas, este trabalho teve como objetivo isolar, purificar e determinar a estrutura primÃria parcial da cadeia beta de uma ficobiliproteÃna presente na alga marinha vermelha Hypnea musciformis. A ficobiliproteÃna (HMp) foi isolada atravÃs da precipitaÃÃo do extrato proteico com sulfato de amÃnio e purificada por cromatografia de troca iÃnica. A eletroforese em gel de poliacrilamida revelou que a HMp possui duas bandas proteicas em torno de 20 kDa e 22 kDa. A banda de 22 kDa foi excisada do gel e digerida com a enzima proteolÃtica tripsina. Os peptÃdeos oriundos da digestÃo foram submetidos à fragmentaÃÃo em espectrÃmetro de massas. Os fragmentos gerados foram utilizados para sequenciar os peptÃdeos e estes na identificaÃÃo de proteÃnas a partir dos bancos de dados existentes. A partir dessas informaÃÃes, iniciadores foram desenhados para amplificar o gene da cadeia beta da ficobiliproteÃna de Hypnea musciformis (bhmp) a partir do DNA genÃmico da alga. O gene amplificado foi sequenciado e os dados brutos foram processados pela ferramenta Phred/Phrap/Consed. A sequÃncia processada foi traduzida para obtenÃÃo da estrutura primÃria parcial de bhmp. A traduÃÃo resultou em uma sequÃncia de 87 resÃduos de aminoÃcidos e HMp apresentou identidade com diversas ficoeritrinas de algas vermelhas.
64

Utilização da macroalga Sargassum sp. como adsorvente natural no controle de poluição por cobre em meio aquoso / Use of seaweed Sargassum sp. as adsorbents natural in control of pollution by copper in aqueous medium

VEIMROBER JÚNIOR, Lúcio Adérito dos Anjos 24 September 2010 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-10-10T15:31:37Z No. of bitstreams: 1 Luci Aderito dos Anjos Veimrober Junior.pdf: 1092568 bytes, checksum: ad49f9ae45bed026a99c5b0fa0d46db3 (MD5) / Made available in DSpace on 2016-10-10T15:31:37Z (GMT). No. of bitstreams: 1 Luci Aderito dos Anjos Veimrober Junior.pdf: 1092568 bytes, checksum: ad49f9ae45bed026a99c5b0fa0d46db3 (MD5) Previous issue date: 2010-09-24 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The deposition of heavy metals in aquatic environments is a growing phenomenon related to industrial processes and dump domestic use, whose production has increased significantly to meet the great demand today. The purpose of this study was to evaluate the adsorption capacity of copper in aqueous solutions by macroalgae "Sargasso" collected on the beaches of the north coast of Pernambuco. These were washed, dried in the greenhouse at ambient temperature (37 ± 1.0 ° C), crushed in a grinder of knives and classified. To optimize the process we used a 23 factorial design, in duplicate, with the central point in triplicate, to assess the influence of the amount of algae (0.05 to 0.25 g) of contact time (2 to 6 h) and pH buffer (3.0 to 5.0) with a particle size of 35 mesh seaweed and agitation at 200 rpm at biorretenção Copper. The tests were performed biosorption by placing the alga in contact with 25 mL of a solution containing 50 mg.L-1 for Cu2 + in acetate buffer 0.1 mol L-1 under the conditions of the experimental design. The concentration of Cu2 +, before and after the tests were determined by Atomic Absorption Spectrometry in Flame. The amount of copper adsorbed in mg per gram of adsorbent varied from 3.11 to 19.38. All the main variables were significant in a 95% level of confidence. From the linearization of the Langmuir equation, we obtained a maximum adsorption capacity of 1.248 mg.g-1 and an adsorption constant of 0.335 L.mg-1. The correlation coefficient (R2) between the data and the model was satisfactory (0.9645). The breakthrough curves were obtained until the entire bed was saturated by ions of the solution. The time was set according to the flow, using a time of 8 hours with a flow rate of 2.0 mL min-1 when there was a stabilization process. Algae Sargasso shown to have a high potential to remove copper from aqueous solutions. This way they can be used to control pollution of copper in aqueous media. / A deposição de metais pesados em ambientes aquáticos é um fenômeno crescente relacionado aos processos industriais e despejos de uso doméstico, cuja produção tem aumentado de forma significativa para atender à grande demanda atual. A proposta deste trabalho foi avaliar a capacidade de adsorção de Cobre em soluções aquosas por macroalgas “Sargaço” coletadas nas praias do litoral norte de Pernambuco. Estas foram lavadas, secas em casa de vegetação a temperatura ambiente (37±1,0°C),trituradas em moinho de facas e classificadas. Para otimização do processo foi utilizado um planejamento fatorial 23, em duplicata com ponto central em triplicata, para avaliar a influência da quantidade de alga (0,05 a 0,25g), do tempo de contato (2 às 6h) e do pH do tampão (3,0 a 5,0) com granulometria da alga de 35 mesh e agitação a 200 rpm na biorretenção do Cobre. Os ensaios de biossorção foram realizados colocando-se a alga em contato com 25 mL de uma solução contendo 50 mg.L-1 de Cu2+ em tampão acetato 0,1mol.L-1, nas condições do planejamento experimental. Os teores de Cu2+, antes e depois dos ensaios, foram determinados por Espectrometria de Absorção Atômica em Chama. A quantidade de Cobre adsorvido em mg por grama de adsorvente variou de 3,11 a 19,38. Todas as variáveis principais foram significativas em um nível de 95% de confiança. A partir da linearização da equação de Langmuir, foi possível obter uma capacidade máxima de adsorção de 1,248 mg.g-1 e uma constante de adsorção de 0,335 L.mg-1. O coeficiente de correlação (R2) entre os dados e o modelo foi satisfatório (0,9645). As curvas de ruptura foram obtidas até que todo o leito fosse saturado pelos íons da solução. O tempo foi definido de acordo com a vazão, utilizando-se um tempo de 8 horas com uma vazão de 2,0 mL.min-1 quando houve uma estabilização do processo. As algas Sargaço mostraram ter um alto potencial para remover Cobre de soluções aquosas. Desta forma elas podem ser utilizadas no controle de poluição de cobre em meio aquoso.
65

Antitumor potential of alginates isolated from the seaweed brown sargassum vulgare c. agardh (1820) / Potencial antitumoral de alginatos isolados da alga marinha marrom sargassum vulgare c. agardh (1820)

Alessandra de Paula Alves Sousa 13 January 2006 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Alginates are natural polysaccharides composed of linear polymers of 1-4 linked beta-D- mannuronic and alfa-L-guluronic acid residues in widely varying composition and sequential arrangements. The purpose of this study was to evaluate the anti cancer potential of two alginates âV (low viscosity) and +V (high viscosity), isolated from the seaweed Sargassum vulgare. Alginates were tested for cytotoxicity using the brine shrimp lethality assay, sea urchin development assay, hemolysis assay and MTT assay using HL-60, MCF-7, CEM, HCT-8 and B16 tumor cell lines. None of the compounds tested showed in vitro toxicity. On the other hand, alginates showed antitumor activity in vivo against Sarcoma 180 cells transplanted in mice. Both alginates inhibited the growth of solid tumor in mice implanted with 5 x 105 tumor cells after both oral and intraperitoneal administration at 50 and 100 mg/m2, as well as 25 mg/m2 after oral administration. Alginate +V presented higher inhibition effects after oral administration. The association of alginate +V (25 mg/m2) with 5-FU (15 mg/m2) showed an increasing activity against tumor compared to +V individually. Alginates antitumor activity at 50 and 100 mg/m2 was related to the tumor proliferation rate inhibition, as observed by reduction of Ki-67 staining in tumor of the treated-animals. The histopathological analysis revealed that both alginates administrated at 50 and 100 mg/m2 presented hepatotoxicity and nefrotoxicity, being -V was more toxic than +V. The kidney perfusion assay demonstrated that âV was more toxic than +V, corroborating date from histopathological analysis. The histopathological analysis of spleen showed that both alginates cause the enlargement of the white pulp of treated animals, suggesting that the observed antitumor activity could be related to alginates immunomodulatory properties. In fact, the alginates treatment (25 mg/m2) prevents the reduction number of leukocytes and lymphocytes, induced by 5-FU treatment as observed from the hematological analysis. / Alginato à um biopolÃmero natural, constituÃdo por ligaÃÃes lineares (1-4) de &#946;-D-Ãcido manurÃnico e &#945;-L-Ãcido gulurÃnico arranjados em seqÃÃncias e proporÃÃes nÃo regulares ao longo da cadeia. Este trabalho visou estudar o potencial antitumoral de dois alginatos com diferentes viscosidades isolados da alga marinha Sargassum vulgare, denominados de âV (menos viscoso) e +V (mais viscoso). Os ensaios atividade antimitÃtica no desenvolvimento do ouriÃo-do-mar, atividade antiproliferativa nas linhagens tumorais HCT-8, MCF-7, HL-60, CEM e B-16, atividade hemolÃtica e toxicidade em Artemia sp, mostraram que ambos os alginatos nÃo possuem toxicidade in vitro. No entanto, os alginatos âV e +V apresentaram atividade antitumoral in vivo no modelo experimental do Sarcoma 180. Ambos os alginatos administrados por via oral e intraperitoneal nas concentraÃÃes de 50 e 100 mg/m2, bem como na concentraÃÃo de 25 mg/m2 por via oral inibiram o crescimento do tumor sÃlido em camundongos transplantados com 5 x 105 cÃlulas tumorais. O alginato +V administrado por via oral apresentou um maior efeito inibitÃrio. O tratamento do alginato +V por via oral (25 mg/m2) associado ao 5-FU (15 mg/m2) promoveu um aumento da resposta contra o tumor quando comparado ao tratamento com o alginato +V isoladamente. A inibiÃÃo da proliferaÃÃo das cÃlulas tumorais, determinada por imunohistoquÃmica com o Ki-67, foi observada em ambos os tratamentos por via oral e intraperitoneal com os alginatos âV e +V nas concentraÃÃes de 50 e 100 mg/m2. As anÃlises histopatolÃgicas revelaram que os alginatos âV e +V administrados nas concentraÃÃes de 50 e 100 mg/m2 por via oral e intraperitoneal possuem toxicidade hepÃtica e renal, no entanto, o alginato âV apresentou maior toxicidade que o alginato +V. O estudo da nefrotoxicidade avaliada no sistema de perfusÃo renal demonstrou que o alginato âV tambÃm apresenta um maior efeito que o alginato +V. A anÃlise histopatÃlogica do baÃo revelou que ambos os alginatos levam a uma hiperplasia da polpa branca nos animais tratados, o que sugere que a atividade antitumoral esteja relacionada Ãs propriedades imunomoduladoras desses compostos. De acordo com a anÃlise hematolÃgica, os animais tratados com o 5-Fu (15 mg/m2) apresentaram leucopenia e linfocitopenia, sendo este quadro revertido com o tratamento associado com os alginatos âV e +V (25 mg/m2).
66

Atividades antinociceptiva e antiinflamatÃria dos polissacarÃdeos sulfatados da alga marinha vermelha Gracilaria cornea J. Agardh / Antinociceptive and anti-inflammatory activities of sulfated polusaccharides from the red marine alga Gracilaria cornea J. Agardh (1852) in animals

Chistiane Oliveira Coura 21 February 2011 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / As algas marinhas sÃo fontes naturais de polissacarÃdeos sulfatados detentores de diversas atividades biolÃgicas (anticoagulante, antitrombÃtica, antinociceptiva, antiinflamatÃria etc) e que exibem mÃnimos efeitos tÃxicos, sendo considerados de grande interesse para as indÃstrias farmacÃuticas e alimentÃcias. O presente trabalho teve como finalidade avaliar os efeitos dos polissacarÃdeos sulfatados totais (PST) da alga marinha vermelha Gracilaria cornea (Gc) em modelos clÃssicos de experimentaÃÃo animal nos ensaios de nocicepÃÃo e inflamaÃÃo aguda. Foram utilizados camundongos Swiss machos (18-25g) e ratos Wistar machos (120-260g). O rendimento de PST-Gc obtidos da extraÃÃo por digestÃo enzimÃtica (6 h; 60ÂC) foi 16,75  0,98%. Os PST-Gc mostraram-se capazes de reduzir (p<0,05) o nÃmero de contorÃÃes abdominais induzidas por Ãcido acÃtico (0,8%) em 66,2; 65,3 e 96,3% para as doses 3, 9 e 27 mg kg-1 (i.v.), respectivamente). No teste de formalina, os PST-Gc inibiram (p<0,05) o tempo de lambedura em ambas as fases do teste (56,1 e 93,2%-primeira fase; 88,2 e 98,0%-segunda fase para as doses 9 e 27 mg kg-1 (i.v.), respectivamente), enquanto a dose de 3 mg kg-1 mostrou efeito apenas na segunda fase do ensaio. No teste da placa quente, o efeito antinociceptivo dos PST-Gc foi observado apenas no tratamento com a dose de 27 mg kg-1 (i.v.). Estes resultados sugerem que os efeitos analgÃsicos das diferentes doses dos PST-Gc ocorram por mecanismo de aÃÃo central e perifÃrica. O modelo de peritonite demonstrou que os PST-Gc reduziu a migraÃÃo de leucÃcitos totais em 52,7%) e de neutrÃfilos em 59% na dose de 3 mg kg-1 (s.c.). Por outro lado, as doses (3 e 9 mg kg-1; s.c.) inibiram o edema de pata induzido por carragenana, especialmente na terceira hora, sendo os efeitos confirmados pela atividade de MPO no tecido da pata (p<0,05), alÃm da reduÃÃo (p<0,05) do edema de pata induzido por dextrana no intervalo de 30min e na primeira hora em todas as doses testadas. Finalmente, ensaio de toxicidade subcrÃnica foi realizado em grupos de 6 camundongos (machos), os quais receberam: Salina (0,15 M; i.p.) e PST-Gc (9mg kg-1; i.p.), durante 14 dias consecutivos. Os resultados mostraram que as administraÃÃes dos PST-Gc nÃo traduziram diferenÃas em termos de massa corpÃrea (p>0,05). Adicionalmente, os PST nÃo proporcionaram alteraÃÃes no peso dos ÃrgÃos (coraÃÃo, fÃgado, rim, baÃo e timo) em relaÃÃo à massa corpÃrea dos animais, exceÃÃo ao baÃo (p<0,05), sugerindo uma propriedade de funÃÃo imunomoduladora. Nenhuma alteraÃÃo hepÃtica pelas dosagens bioquÃmicas (TGO e TGP) ou renal tambÃm foi observada (p>0,05), ou sobre os parÃmetros hematolÃgicos (hemÃcias, hemoglobina, hematÃcrito, VCM, HGM, CHCM, leucÃcitos, linfÃcitos, monÃcitos, neutrÃfilos e plaquetas) considerados, exceÃÃo da hemoglobina (p<0,05). Portanto, a alga marinha vermelha Gracilaria cornea apresenta polissacarÃdeos sulfatados seguros e detentores de atividades antinociceptiva e antiinflamatÃria. / Marine algae are natural sources of sulfated polysaccharides possessing several biological activities (anticoagulant, antithrombotic, antinociceptive, anti-inflammatory etc.) and that exhibit minimal toxicity and are considered of great interest to the pharmaceutical and food industries. This study aimed to evaluate the effects of sulfated polysaccharides total (SPT) from the red seaweed Gracilaria cornea (Gc) in classical models of animal experimentation. Swiss mice male (18-25g) and male Wistar rats (120-260g) in nociception and acute inflammation assays were used. The SPT-Gc yield extraction obtained by enzymatic digestion (6 h, 60  C) was 16.75  0.98%. The SPT-GC was able to reduce (p<0.05) the number of writhing induced by 0.8% acetic acid (66.2, 65.3 and 96.3% for 3, 9 and 27 mg kg-1 (i.v.), respectively). In formalin test, the SPT-Gc inhibited (p<0.05) licking time in both phases of testing (56.1 and 93.2% first-phase, 88.2 and 98.0% second- phase for 9 and 27 mg kg-1 (i.v.), respectively), whereas the dose 3 mg kg-1 had only effect in the second phase of the trial. In the hot plate test, the antinociceptive effect of SPT-Gc were seen only in treatment with 27 mg kg-1 (i.v.). These tests in mice suggest that the analgesic effects occur through mechanism of action of central and peripheral. The model of peritonitis demonstrated that SPT-Gc exert effects on the migration of total leukocytes (52.7%) and neutrophils (59%) at a dose of 3 mg kg-1 (s.c.). On the other hand, the doses (3 and 9 mg kg-1, s.c.) appear able to inhibit the paw edema induced by carrageenan, particularly at the third hour, with the effects confirmed by MPO activity in paw tissue (p<0.05) and the occasional reduction (p<0.05) of paw edema of mice induced by dextran in the first hour at all doses tested. Finally, subchronic toxicity test was conducted in groups of 6 mice (males), which received: Saline (0.15 M, i.p.) and SPT-Gc (9 mg kg-1, i.p.) for 14 consecutive days. The results showed that the administrations of SPT-Gc did not show to differences in body mass (p>0.05). Additionally, the SPT did not produce changes in organ weights (heart, liver, kidney, spleen and thymus) in relation to body mass of animals, except the spleen (p<0.05), suggesting an immunomodulatory property. No change for liver biochemical tests (AST and ALT) or renal function was also observed (p>0.05), or on the hematological parameters (erythrocytes, hemoglobin, hematocrit, MCV, HGM, MCHC, leucocytes, lymphocytes, monocytes, neutrophils and platelets) considered, except hemoglobin (p<0.05). Therefore, the red seaweed Gracilaria cornea sulfated polysaccharides present security and antinociceptive and antiinflammatory activities
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Efeitos da Lectina da Alga Marinha Vermelha Solieria filiformis (KÃtzing) P.W. Gabrielson na NocicepÃÃo e InflamaÃÃo em Animais / Effects of the Lectin from the Red Marine Alga Solieria filiformis (KÃtzing) P.W. Gabrielson in Nociception and Inflammation in Animals

Ticiana Monteiro Abreu 24 February 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / As algas marinhas sÃo fontes de compostos bioativos, os quais vÃm despertando interesse em aplicaÃÃes farmacolÃgicas. Dentre esses, destacam-se as lectinas, que sÃo (glico)proteÃnas que se ligam a mono ou oligossacarÃdeos especÃficos. O objetivo desse trabalho foi isolar a lectina da alga marinha vermelha Solieria filiformis (LSf), investigar as suas propriedades na nocicepÃÃo e na inflamaÃÃo aguda e seus possÃveis sinais de toxicidade em animais. Inicialmente, a LSf foi purificada por extraÃÃo com tampÃo Tris-HCl 25mM, pH 7,5, precipitaÃÃo com sulfato de amÃnio (70%) e cromatografias em colunas de DEAE-celulose e Sephadex G-100. Na avaliaÃÃo das atividades biolÃgicas, grupos de animais (n=6) foram submetidos ao prÃ-tratamento com a LSf (1, 3 ou 9 mg/kg; i.v.), 30 min antes do estÃmulo nociceptivo ou inflamatÃrio. A atividade antinociceptiva foi avaliada em camundongos Swiss machos atravÃs dos ensaios de contorÃÃes abdominais induzidas por Ãcido acÃtico 0,8%, teste da formalina a 2% e da placa quente. Morfina e indometacina (5 mg/kg; s.c.) foram utilizadas como controles. A atividade anti-inflamatÃria em ratos Wistar machos foi avaliada atravÃs dos ensaios de peritonite induzida por carragenana - Cg (700 Âg/cav) e de edema de pata induzidos por Cg (700 Âg/pata); dextrano (500 Âg/pata); ou pela prÃpria LSf (9 mg/kg). Dexametasona (1 mg/kg; s.c.) foi utilizada como controle. A aÃÃo edematogÃnica da LSf (1, 3 ou 9 mg/kg) foi avaliada atravÃs da sua aplicaÃÃo na pata de ratos e da modulaÃÃo farmacolÃgica do edema formado. O estudo da toxicidade da LSf (9 mg/kg;i.v.) foi realizado atravÃs da sua aplicaÃÃo em camundogos (7 dias) e da anÃlise dos parÃmetros fÃsicos, bioquÃmicos e histolÃgicos. A LSf reduziu significativamente o nÃmero de contorÃÃes abdominais e o tempo de lambedura da pata na segunda fase do teste da formalina, porÃm nÃo prolongou o tempo de reaÃÃo na placa quente. A LSf tambÃm inibiu a migraÃÃo celular na peritonite induzida por Cg e os edemas de pata induzidos por Cg, dextrano e LSf. Ademais, LSf apresentou atividade edematogÃnica, que foi inibida por indometacina e dexametasona. Adicionalmente, a administraÃÃo da LSf por 7 dias nÃo apresentou sinais de danos sistÃmicos, exceto pela reduÃÃo no nÃvel de fosfatase alcalina e esplenomegalia. Concluindo, a LSf possui propriedades antinociceptiva, anti-inflamatÃria (i.v.) e edematogÃnica (i.pl.), podendo representar um potencial agente terapÃutico e uma possÃvel ferramenta para o estudo da inflamaÃÃo. / The seaweeds are a source of bioactive compounds, which gained importance in pharmacological applications. Among these, there are the lectins, which are (glyco)proteins that bind to specific mono or oligosaccharides. The aim of this study was to isolate the lectin from the red seaweed Solieria filifmoris (LSf), investigate its properties in acute nociception and inflammation, and their possible signs of toxicity in animals. Initially, the LSf was purified by extraction with Tris-HCl buffer 25 mM (pH 7,5), precipitation with ammonium sulfate (70%) and chromatographies in DEAE-cellulose and Sephadex G-100 columns. In the evaluation of the biological activities, animals groups (n=6) were submitted to pretreatment with LSf (1, 3 or 9 mg/kg; i.v.), 30 min before of the nociceptive or inflammatory stimulus. The antinociceptive activity was evaluated in male mice Swiss using the abdominal writhing test induced by acetic acid 0,8%, the formalin test to 2% and the hot plate test. Morphine and indomethacin (5 mg/kg; s.c.) were used as controls. The anti-inflamatory activity in male rats Wistar was assayed through of the peritonitis induced by carrageenan - Cg (700 Âg/cav) and of the paw edemas Cg- (700 Âg/paw), dextran- (500 Âg/paw) or LSf-induced (9 mg/kg) models. Dexamethasone (1 mg/kg; s.c.) was used as control. The LSf edematogenic action (1, 3 or 9 mg/kg) was evaluated by the application of this lectin in the rat paws and by the pharmacological modulation of the edema formed. The toxicity study of LSf (9 mg/kg; i.v.) was carried out through of its application in mice (7 days) and of the analysis of the physical, biochemical and histological parameters. LSf significantly reduced the number of abdominal writhing and the paw licking time in the second phase of formalin test, but didnât prolong the reaction time in hot plate test. The LSf also inhibited the cell migration in peritonitis induced by Cg and the paw edemas induced by Cg, dextran and LSf. Moreover, LSf showed edematogenic activity, which was inhibited by indomethacin and dexamethasone. Additionally, the LSf administration for 7 days presented no signs of systemic damages, except for the reduced level of alkaline phosphatase and splenomegaly. Concluding, the LSf has antinociceptive, anti-inflammatory (i.v.) and edematogenic (i.pl.) properties and could represent a potential therapeutic agent and a possible tool for the inflammation study.
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Associação de anfípodes herbívoros com a alga parda Sargassum filipendula e suas epífitas : variação temporal e efeito da dieta sobre a aptidão / variação temporal e efeito da dieta sobre a aptidão : temporal variation and effect of diet on fitness

Machado, Glauco Barreto de Oliveira, 1988- 07 March 2013 (has links)
Orientadores: Fosca Pedini Pereira Leite, Silvana Gomes Leite Siqueira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T12:09:46Z (GMT). No. of bitstreams: 1 Machado_GlaucoBarretodeOliveira_M.pdf: 985183 bytes, checksum: 0ebee94e2eacdcb899d86341f1c8dc83 (MD5) Previous issue date: 2013 / Resumo: Macroalgas oferecem alimento e hábitat para pequenos herbívoros, como anfípodes. O papel da macroalga como alimento é um dos principais fatores que influencia a interação herbívoro-macroalga. Dessa forma, para compreender essa interação, é imprescindível conhecer as consequências da dieta sobre a aptidão de pequenos herbívoros e a associação desses animais com as macroalgas em campo. Nesse estudo, avaliamos a variação temporal de anfípodes herbívoros da família Ampithoidae e da alga parda Sargassum filipendula e suas epífitas. Em complemento, investigamos o efeito do consumo de algas com diferentes características (Sargassum filipendula e duas algas epífitas, Dictyota cervicornis e Hypnea musciformis) sobre a aptidão de dois ampitoídeos, Cymadusa filosa e Sunampithoe pelagica, bem como a preferência e taxa alimentar desses anfípodes. A composição das espécies de Ampithoidae variou quanto ao tempo e foi influenciada pela biomassa de Sargassum e pela intensidade de epifitismo. Sunampithoe pelagica destacou-se como a espécie de ampitoídeo mais abundante, apresentando forte associação com a biomassa de Sargassum. As espécies C. filosa, Ampithoe marcuzzi e A. ramondi ocorreram em menor abundância e acompanharam a variação da biomassa de epífitas. Nos experimentos de aptidão, jovens de S. pelagica alimentados com Sargassum, em comparação àqueles nos tratamentos com Hypnea e Dictyota, apresentaram maior sobrevivência, o que sugere uma dieta restrita apresentada por essa espécie. Para C. filosa, a sobrevivência foi semelhante entre jovens submetidos às três dietas, porém, aqueles alimentados com Sargassum apresentaram maior crescimento e sucesso reprodutivo. Em um experimento de múltipla escolha de algas, adultos de C. filosa e S. pelagica apresentaram maior preferência de consumo pela alga Sargassum. Quando não oferecida escolha quanto ao alimento, as três algas foram consumidas por adultos de C. filosa a uma mesma taxa. Em contraste, Sargassum foi à alga mais consumida por adultos de S. pelagica no experimento de taxa alimentar. Apesar de ambas as espécies de anfípodes apresentarem maior preferência e sucesso ao consumirem Sargassum, elas responderam de maneiras distintas quando oferecidas outras algas, o que pode refletir as diferenças observadas entre essas espécies quanto aos seus padrões de ocorrência em campo. Nesse sentido, enquanto um importante componente na interação entre pequenos herbívoros e macroalgas, a dieta pode influenciar as respostas de anfípodes herbívoros às variações de biomassa das macroalgas. Além disso, nossos resultados reforçam a importância de se considerar as especificidades de cada herbívoro para compreensão do impacto desses animais sobre a comunidade de algas / Abstract: Macroalgae offer food and habitat for small herbivores, such as amphipods. The role of the macroalgae as food is one of the main driving factors of the herbivore-macroalga interaction. Hence, in order to comprehend this interaction, one must necessarily know the consequences of the diet on the fitness of small herbivores and on the association between these animals and the algae in the field. We herein assess the temporal variation of herbivore amphipods, of the Ampithoidae family, and of the brown seaweed Sargassum filipendula and its epiphytes. In addition, we explore the effects of the consumption of algae with different characteristics (Sargassum filipendula and two epiphytes, Dictyota filosa and Sunampithoe pelagica) on the fitness of two ampithoids, Cymadusa filosa and Sunampithoe pelagica, as well as on their feeding preference and rate. The composition of Ampithoidae species displayed temporal variation and was influenced by the Sargassum biomass and the intensity of epiphytism. Sunampithoe pelagica revealed itself as the most abundant species of Ampithoidae, and was strongly associated to the Sargassum biomass. The C. filosa, Ampithoe marcuzzi and A. ramondi species were less abundant, and they accompanied the variation of the epiphyte biomass. In the fitness experiments, young S. pelagica being fed Sargassum, as compared to the groups being fed Hypnea and Dictyota, displayed larger survival rates. This suggests that this species has a restricted diet. Regarding C. filosa, the survival rate was similar for the young specimens subjected to three diets, but those fed Sargassum showed greater growth and higher reproductive success. In a multiple choice experiments, C. filosa and S. pelagica adults were shown to prefer consuming Sargassum. When they were not offered a choice, C. filosa adults consumed the three algae at the same rate. In contradistinction to this, in the feeding rate experiment S. pelagica adults consumed Sargassum the most. In spite of the two amphipod species displaying greater preference and success rates when consuming Sargassum, they reacted differently when other algae was offered them, which might explain the observed differences regarding their occurrence patterns in the field. Therefore, as an important factor of herbivore-macroalgae interaction, feeding can influence the responses of herbivorous amphipods to changes in macroalgae biomass. Furthermore, our results stress the importance of considering the specificities of each herbivore in order to understand the impact of these animals on the community of algae / Mestrado / Ecologia / Mestre em Ecologia
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Récolter la mer : des savoirs et des pratiques des collecteurs d'algues à la gestion durable des ressources côtières dans le Finistère (Bretagne) / Harvesting the sea : knowledge and practices of seaweed harvesters to the sustainable management of coastal resources in Finistère (Brittany)

Garineaud, Clément 27 March 2017 (has links)
Après de multiples cycles au cours des siècles passés, la récolte des algues dans le Finistère se renouvelle et s’inscrit comme une filière d’avenir. Au-delà des changements socio-économiques, elle se confronte aux problématiques actuelles de conservation de la biodiversité et de partage de l’espace maritime. Comment dès lors concilier activités anthropiques et préservation du milieu ? La démarche ethnoécologique mobilisée, interroge la gestion des ressources par les populations locales au travers de leurs engagements — pratiques, savoirs locaux et représentations. L’objectif de la thèse est donc double : comprendre les dynamiques des engagements des collecteurs d’algues ? Et comprendre comment ils sont mobilisés et ils évoluent face aux enjeux actuels ? Grâce à une enquête ethnographique et aux méthodes de l’ethnoécologie, nous avons interrogé les cadres scientifiques, sociaux et administratifs de manière diachronique pour saisir le contexte et les enjeux. Ensuite, nous avons questionné l’identité des collecteurs au travers des « statuts administratifs », puis de cinq profils émergeant des données. Cette diversité des formes d’engagement se retrouve dans les perceptions sensorielles mobilisées lors de la récolte, dans les systèmes de classification vernaculaires des algues et dans l’appréhension de l’espace. L’analyse de ces trois dimensions révèle un ensemble très riche de savoirs « intimes », « incorporés » et « situés » indissociables des techniques, sur les algues, le milieu aquatique et les dynamiques de l’écosystème. Différents éléments au travers des savoirs et des représentations éclairent les conflits et illustrent l’influence des scientifiques et des industriels sur les collecteurs. L’aléa climatique de l’hiver 2013-2014, en impactant la ressource algale, a contraint les collecteurs d’algues à s’adapter. Il a révélé les jeux d’acteurs dans les filières et la nature composite, voire hybride des engagements, premier pas vers une cogestion. / After several cycles over the course of past centuries, seaweed harvesting in Finistere is once again experiencing a revival and emerging as a promising sector. Beyond socio-economic transformations, it is also faced with current issues of biodiversity conservation and the sharing of maritime space. How can human activity and preservation of the environment be reconciled? The mobilized ethnoecological approach looks at resource management by local communities through their engagement - practices, traditional ecological knowledge, and representations. The aim of this thesis is thus twofold: understanding the dynamics of seaweed harvesters' engagement, and understanding how they mobilize and cope with current issues. Through ethnographic survey and ethnoecological methods, the scientific, social, and administrative frameworks were investigated diachronically to understand the context and the issue. The identity of the collectors were studied through both 'administrative statuses' as well as five profiles that emerged from the data. This diversity in forms of engagement is reflected in the sensory perceptions mobilized during harvesting, in the vernacular classifications of seaweed, and in how space is apprehended. The analysis of these three dimensions reveals a rich body of 'intimate', 'embodied', and 'situated' knowledge that is inextricable from practices relating to seaweed, aquatic environments, and ecosystem dynamics. Finally, various elements across knowledge and representations shed light on conflicts and illustrate the influence of science and industry on collectors. The climate event that took place during the winter of 2013–2014, for example, left an impact on seaweed resources and forced collectors to adapt. It revealed the interplay between actors of the various sectors and the composite (or even hybrid) nature of their engagement, a first step towards co-management.
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Development of a model for evaluating and optimizing the performance of integrated multitrophic aquaculture (IMTA) systems

Lamprianidou, Fani January 2015 (has links)
Earth’s population is expected to reach 9 billion by 2050. Ensuring food security for the growing world population is one of today’s society’s major challenges and responsibilities. Aquatic products have the potential to contribute significantly in the growing population’s dietary requirements. Since increasing the pressure on most natural fish stocks is now widely agreed not to be an option, the aquaculture sector needs to grow. The challenge is to increase aquaculture production without depleting natural resources or damaging the environment but also in a financially sustainable way. Integrated Multitrophic Aquaculture (IMTA) is one method of sustainable aquatic production. Integrating bioremediatory organisms that extract particulate organic matter or dissolved inorganic nutrients with monocultures of fed species has the potential of reducing the particulate and soluble waste loads from effluents, whilst producing a low-input protein source that may also increase the farm income. IMTA is a viable solution for mitigating the environmental impact of waste released from fish farms. The fish waste is exploited as a food source for lower trophic, extractive organisms giving an added value to the investment in feed. Studies up to now have shown that under experimental conditions as well as in small-scale commercial studies, various filter-feeding, deposit-feeding and grazing species can ingest fish waste particles. The aim now is to achieve IMTA optimization, where extractive organisms can ingest most of the finfish waste food and excretions. Any such design is likely to be complex incorporating a multidisciplinary approach, and therefore to date a reason why most studies have failed to prove the environmental and economic benefits of IMTA. Consequently, the aim of this study is to develop ways of selecting an ideal combination of species for a specific locality, manage the cultures in a way that ensures the maximum nutrient recycling feasible per unit of area; and ensure high growth rate of the extractive organisms while being financially beneficial. The approach taken was a combination of investigative literature reviews, computer modelling work and small-scale growth trials to determine the relative growth of extractive organisms fed fishfeed and waste, followed by the development of a systems-based model of interaction and growth efficiency for combinations of organisms within an IMTA system. This study starts by investigating, with small-scale laboratory experiments, the potential of two organic extractive species, the lugworm, Arenicola marina and the sea urchin, Psammechinus miliaris, as organic extractive components of IMTA systems. Their ability to consume and assimilate salmon faeces was evaluated as well as their remediation efficiency. This was done by comparing the carbon, nitrogen and phosphorus content of the pellet-faeces mixture to that of the sea urchin faeces and sea urchin gonad content. Their growth, gonadosomatic index (GSI) (for the sea urchins), tissue carbon, nitrogen and phosphorous content were compared between seaweed diets and a diet consisting of a mixture of salmon faeces and feed pellets. The results showed statistically significant gonad carbon content for the sea urchins fed with faeces. Similarly, statistically significant higher phosphorous content was found in the tissues of the lugworms fed with the mixture of salmon faeces and pellets than in the lugworms of the other two groups. The subsequent and main phase of this study was the development of a model for optimising IMTA performance. The modelling process included model development, run, optimization and risk assessment. The IMTA model developed consisted of Atlantic salmon Salmo salar, the sea urchin Paracentrotus lividus and the macroalgae Ulva sp. It simulates the growth as well as the uptake and release of nitrogen by these organisms under environmental conditions of a hypothetical site on the west coast of Scotland. The aim of the model was to maximize the potential of IMTA in terms of productivity and to reduce the amount of nutrients that are released in the environment, and thus to contribute towards a more sustainable and productive form of aquaculture. The IMTA model developed can be re-parameterised to simulate the growth and nutrient uptake of different species and the growth and nutrient uptake under different environmental conditions. This capacity of the model was used in order to do a comparative study of the nitrogen bioremediation potential of three different invertebrate species, cultivated as part of an IMTA. These species were the lugworm (Arenicola marina), the blue mussel (Mytilus edulis) and the purple sea urchin (Paracentrotus lividus). The results of this comparative study showed that weight for weight, M. edulis is more efficient in removing POM than P. lividus that is in turn better than A. marina with regard to the amount of nitrogen they can assimilate. But in terms of cultivation area required for the production of the same total biomass, P. lividus was better at removing POM followed by M. edulis and then by A. marina.

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