Les efflorescences phytoplanctoniques nuisibles et/ou toxiques impactent depuis très longtemps les écosystèmes marins du monde entier. Ces développements massifs ont un effet néfaste sur les écosystèmes et leur exploitation. Les lagunes du Languedoc-Roussillon sont touchées depuis plusieurs décennies. En plus des risques sanitaires récurrents dus aux genres Dinophysis (toxines DSP) et Alexandrium (toxines PSP), Vulcanodinium rugosum a été identifiée en 2011 dans la lagune d’Ingril. Cette nouvelle espèce est productrice de pinnatoxines (neurotoxines). A travers ces travaux de thèse, la biologie de cette nouvelle espèce (cycle de vie, condition de croissance, production de toxines), ses capacités de contamination des mollusques et sa distribution géographique dans les lagunes limitrophes ont été étudiées sur des cultures au laboratoire et via des suivis environnementaux.Les résultats de cette étude ont mis en évidence le caractère thermophile et euryhalin de cette microalgue (croissance optimale à 25°C et à une salinité de 40 ) avec des plages de croissance comprises entre 20 et 30°C. Sa capacité à croître sur une source azotée organique (urée) a été observée in vitro. Son expansion à des lagunes du Languedoc-Roussillon autre que l’étang d’Ingril, a été confirmée par la mise en évidence de la contamination des moules par la pinnatoxine G. La survie de ce dinoflagellé dans le tractus digestif des moules et des huîtres prouve que le transfert de coquillages est une source de contamination potentielle des écosystèmes non impactés par cette espèce toxique.Le cycle de vie de V. rugosum n’a pu être élucidé que partiellement, le kyste de résistance n’ayant pas été identifié formellement. Les kystes temporaires apparaissent comme des stades très importants à prendre en considération en raison de leur capacité à se diviser et de leur forte présence sur les macrophytes. Ces formes temporaires de résistance peuvent constituer une source de contamination non négligeable des mollusques dans la lagune de l’Ingril même lorsque les cellules végétatives de V. rugosum sont peu présentes dans la colonne d’eau. En raison des faibles densités de V. rugosum in situ et la difficulté de son identification sur des critères morphologique, sa surveillance dans le cadre du REPHY demeure difficile. Ainsi l’utilisation de systèmes d’échantillonnage passifs (SPATT) constitués de résines qui adsorbent les toxines dissoutes dans l’eau permettrait la détection précoce des toxines associées à ces espèces benthiques émergentes. Cette étude met en évidence la prolifération d’une espèce émergente thermophile qui pourrait avec d’autres et à la faveur de changements climatiques constituer des problèmes sanitaires et économiques importants dans les écosystèmes lagunaires vulnérables de la Méditerranée. / Harmful and / or toxic phytoplankton blooms impact for a long time marine ecosystems worldwide. These massive developments have an adverse effect on ecosystems and their exploitation. The lagoons of the region Languedoc-Roussillon are affected for decades. In addition to recurring health risks from Dinophysis (DSP toxins) and Alexandrium (PSP toxins), Vulcanodinium rugosum was identified in 2011 in the lagoon Ingril. This new species product pinnatoxins (neurotoxins). Through this thesis work, the biology of this new species (life cycle, growth condition, toxin production), its shellfish contamination capacity and geographic distribution in neighboring lagoons were studied on cultures in the laboratory and via environmental monitoring.The results of this study have demonstrated its thermophilic and euryhaline features (optimum salinity and temperature of 25°C and 40 respectively) and its growth ranges between 20 and 30°C. Its ability to grow on an organic nitrogen source (urea) has been showed in vitro. Its expansion in other lagoons of Languedoc-Roussillon, was confirmed by the contamination of the mussels by the pinnatoxin G. The survival of this organism in the digestive tract of mussels and oysters proves that the transfer of shellfish is potentially a source of contamination of new ecosystems not yet affected by this toxic species.The life cycle of V. rugosum has not been fully described because the resistance cyst has not been formally identified. Temporary cysts appear as very important stages to be considered because of their ability to divide and their strong presence on macrophytes. These temporary forms of resistance may be a significant source of contamination of shellfish in the lagoon of the Ingril even when the vegetative cells of V. rugosum are weakly present in the water column. Because of the low densities of V. rugosum in situ and the difficulty of its identification on morphological criteria, the monitoring within the REPHY protocol remains difficult. Thus the use of passive sampling systems (Spatt) made with resins which adsorb toxins dissolved in water would make possible the early detection of toxins associated with these emerging benthic species. This study highlights the growth of an emerging thermophilic species that might with others and thanks to climate change provide important health and economic problems in vulnerable lagoon ecosystems of the Mediterranean.

Plants colonised land 460 million years ago and charophytes represent the closest living relatives of land plants. The ability to live on land may depend on the presence of certain cell wall polysaccharides such as xyloglucan, a hemicellulose exclusively found in land plants (Popper and Fry, 2003). The cell walls of charophytes are poorly characterised. The aim of this project was to use biochemical techniques to characterise the cell wall polysaccharides of charophytic algae in relation to early land plant phylogeny. Hydrolysis of Coleochaete scutata and Chara vulgaris cell walls in 2 M trifluoroacetic acid yielded predominantly GalA, Gal, Glc and Man residues and also some Ara, Xyl and traces of Fuc and Rha. In addition, hydrolysis of Chara pectin revealed an abundance of an unusual monosaccharide, 3-O-methyl-D-galactose, which was structurally identified by a series of 1-D and 2D NMR spectroscopy by COSY, TOCSY, NOESY and HSQC. 3-O-Methyl-D-galactose is more commonly found in lycophyte cell walls where its presence has been suggested to be related to lycophytes’ evolutionarily isolated position (Popper et al., 2001). The newly discovered presence of 3-O-methyl-D-galactose in charophyte pectin suggests that this polymer may be more complex than previously thought. Coleochaete and Chara hemicellulose extracts were fractionated by anion-exchange chromatography into five classes. A strongly anionic fraction from Chara hemicellulose was found to be rich in Glc, Xyl, Gal and Fuc suggestive of a xyloglucan-like polysaccharide. However, XEG was unable to produce diagnostic xyloglucan oligosaccharides in either Coleochaete or Chara hemicelluloses. Xylanase and mannanase digestion of Coleochaete and Chara hemicelluloses gave xylan- and mannan-oligosaccharides. Furthermore, lichenase digestion of Coleochaete hemicellulose yielded an unusual octasaccharide composed of approximately equimolar xylose and glucose. My work has shown that charophyte cell walls are a source of undiscovered monosaccharides and potentially novel pectic and hemicellulosic domains which may have important functions in enabling the successful colonisation of land by plants.

Photosynthetic Microbial Fuel Cell (p-MFC) research aims to develop devices containing photosynthetic micro-organisms to produce electricity. Micro-organisms within the device photosynthesise carbohydrates under illumination, and produce reductive equivalents (excess electrons) from both carbohydrate production and the subsequent carbohydrate break down. Redox mediators are utilised to shuttle electrons between the organism and the electrode. The mediator is reduced by the micro-organism and subsequently re-oxidised at the electrode. However this technology is in its early stages and extensive research is required for p-MFC devices to become economically viable. A basic p-MFC device containing a potassium ferricyanide mediator and the algae Chlorella vulgaris was assembled and tested. From these initial experiments it was realised that much more work was required to characterise cell and redox mediator activities occurring within the device. There is very little p-MFC literature dealing with cellular interaction with redox mediators, but without this knowledge the output of complete p-MFC devices can not be fully understood. This thesis presents research into the reduction of redox mediators by the micro-organisms, including rates of mediator reduction and factors affecting the rate. Both electrochemical and non-electrochemical techniques are used and results compared. Additionally, cellular effects relating to the presence of the mediator are studied; crucial to provide limits within which p-MFCs must be used. After basic characterisation, this thesis presents work into the optimisation of the basic p-MFC. Different redox mediators, photosynthetic species and anodic materials are investigated. Importantly, it is only through fundamental characterization to improve understanding that p-MFCs can be optimised.

The aim of this dissertation was to elaborate the exploration of biologically active secondary metabolites from the marine sponge Cacospongia cf. linteiformis collected from the Bahamas and the soft coral Briareum asbestinum collected from two different sites in Florida State, Boca Raton and Dry Tortugas. In chapter one, a review on previous chemical and biological studies of the marine sponge C. cf. linteiformis and soft coral B. asbestinum is provided. Particular attention is given to spongianolides and briarellins, two important classes of compounds isolated from C. cf. linteiformis and B. asbestinum, respectively, and their structural features and diverse bioactivities. In chapter two, the isolation and relative configuration determination of four epimeric sesterterpenoids, spongianolides E & F (18c, 18d, 19c, 19d) from C. cf. linteiformis collected from the Bahamas are discussed. Thanks to chemical modification (acetylation), diastereomeric 18c&18d and 19c&19d, respectively, were able to be isolated using chromatographic techniques for the first time, and then the relative configurations of 18c, 18d, 19c, 19d were determined based on NOESY NMR experiments. The bioactivity of mixture of compounds 18c, 18d, 19c, 19d were tested and it exhibited inhibition against Schnurri-3 (a regulator of postnatal bone mass). In chapter three, the isolation and structural elucidation of four new compounds, florellins A-D (49-52), from B. asbestinum collected off the coast of Boca Raton, FL are discussed. The molecular structures of these compounds were established by spectroscopic analysis. Compounds 49-52 are the first briarellins containing an acyl group at C-13, while 49 and 50 are the first briarellins possessing acylation at C-15. Florellins A–C (49-51) were screened and found cytotoxic against three human cell lines, BT474, WM266−4 and HEK293. In chapter four, the isolation and structural elucidation of four new compounds, florellins E-H (57-60), from B. asbestinum collected in Dry Tortugas, FL are discussed. The molecular structures of these compounds were established by spectroscopic analysis. Florellins F (58) and H (60) were screened against three human cell lines, BT474, WM266−4 and HEK293, but no cytotoxicity was exhibited. In chapter five, all the experimental procedures are described, including analytical instruments, animal materials, extraction and isolation processes, spectroscopic data and protocols of bioassays. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

Green macroalgae represent an attractive source of renewable carbon. Conversion of algal biomass to useful products requires depolymerization of the cell wall polysaccharides cellulose and ulvan. Cellulose saccharification has been widely studied and involves synergistic action of endoglucanases, exoglucanases, and β-glucosidases. The enzymatic depolymerization of ulvan has not received the same attention and additional studies are required in order to fully understand the mechanisms involved in its biodegradation. Synthetic biology offers the possibility of importing modules such as biomass-degrading systems and biofuel producing pathways from different organisms into a genetically tractable host such as Escherichia coli. In this study it was shown that E. coli expressing the glycosidase CHU2268 of Cytophaga hutchinsonii grows well on cello-oligosaccharides such as cellohexaose, and co-expression with the endoglucanase CenA of Cellulomonas fimi allows growth on untreated crystalline cellulose. Moreover, a model for ulvan utilization was built for the first time based on a polysaccharide utilization locus from the alga-associated flavobacterium Formosa agariphila. It was also shown that F. agariphila, is able to grow using biomass from the green macroalga Ulva lactuca as its sole carbon source, and enzymes with ulvanase activity are induced by the presence of this alga in the culture medium. Enzymes for ulvan depolymerization from F. agariphila, including an ulvan lyase, xylanases and rhamnosidases, were cloned using the PaperClip DNA assembly method and expressed in active form in E. coli. Furthermore, a secretion system based on the use of the Antigen 43 was successfully used to secrete an active ulvan lyase using E. coli and ribosome binding sites of different strengths were studied and used to optimize the system. These results represent a first step for the design of a microorganism capable of utilizing green macroalgal biomass for the production of biofuels and other valuable bio-products.

Using bioinformatics we have identified stm3071 as a possible regulator of anaerobically induced genes involved in metal homeostasis (Price-Carter et al., 2001) and the aim of this study is to determine the function of stm3071 and define the conditions that induce its expression. Cobalt is required for incorporation into cobalamin (vitamin B12) which is important during S. Typhimurium infection. Vitamin B12 is synthesised de novo under anaerobic conditions and is required for metabolism of 1,2-propanediol and ethanolamine which act as sources of carbon and nitrogen when Salmonella is in the gut (Raux et al., 1996; Thiennimitr et al., 2011). Therefore, sensing Co2+ from the environment, and maintaining Co2+ homeostasis, to avoid metal-mediated toxicity, is required for vitamin B12 biosynthesis. Using λ-red based mutagenesis we have constructed a deletion mutant in order to investigate the function of stm3071. We examined the effect of mutation on the utilisation of 1,2-propanediol under anaerobic conditions and ability to produce vitamin B12. We have also tested the effect of mutation on tolerance to cobalt both aerobically and anaerobically. In order to monitor conditions in which Pstm3071 is switched on, a Pstm3071::lacZ transcriptional fusion was constructed in plasmid pRS415. Levels of β-galactosidase activity were measured in the presence of cobalt in both Δstm3071 and SL1344 (wild type strain) under anaerobic conditions. Anaerobic growth experiments and B12 assays showed that stm3071 is not essential for growth or synthesis of vitamin B12. In addition, cobalt tolerance in both aerobic and anaerobic conditions was unaffected. However, as measured by β-galactosidase assay, our data suggests that Pstm3071 expression is induced in the presence of cobalt in the deletion mutant. In contrast, we observed no difference in expression of Pstm3071 in the presence or absence of cobalt in SL1344.

Submitted by (edna.saturno@ufrpe.br) on 2017-02-17T11:54:32Z No. of bitstreams: 1 Mirela Assuncao Simoes.pdf: 1074751 bytes, checksum: 81a2d122c520a14eea7d6b436bd3b529 (MD5) / Made available in DSpace on 2017-02-17T11:54:32Z (GMT). No. of bitstreams: 1 Mirela Assuncao Simoes.pdf: 1074751 bytes, checksum: 81a2d122c520a14eea7d6b436bd3b529 (MD5) Previous issue date: 2009-08-03 / Gracilaria is the best represented genus of red algae, with more than 100 recognized species and is distributed in most tropical and temperate seas of the world. Thus, this genus is distinguished for being the world's leading source of agar. Agar is a substance which can be extracted from the cell wall of some red algae species. Its main feature is the ability to form a gel known generically as phycocolloids. This compound can be purified to be used in a wide variety of industrial products, such as food, medicines, cosmetics, chemicals, textile, among others. The present study aimed to determine the growth of the macroalgae Gracilaria birdiae cultivated in Pau Amarelo, Pernambuco, Brazil and the quality of its phycocolloids (agar). The experiment was divided into two parts: one conducted in field (cultivation of seaweed) and the other in laboratory (quality analysis of the macroalgae; carotenoids extraction and quality assessment of the agar). By comparing the total biomass produced during the dry and rainy seasons, higher values (p <0.01) were observed for the dry season (41.32 kg) in relation to the rainy season (13.36 kg). The maximum relative growth rates obtained at the end of cultivation in the dry period was 7.52% day-1 and the minimum was 0.32% day-1. In the rainy season the same measurements were 5.33 and -2.64% day-1. The bromatological parameters (g/100g) evaluated for the dry and rainy seasons were respectively moisture content and volatile substances (88.37 and 89.06%), proteins (14.78 and 21.48%), ash (41.78 and 40.85%), lipids (5.33% and 4.20%), carbohydrates (38.09% to 33.45%) and carotenoids (5.86 and 6.93 mg / mL). The results show the high performance of 30-day cultivation in this region in addition to the high bromatological properties and good quality of hardness of the agar from these macroalgae, which can be marketed and used for human consumption. / A macroalga Gracilaria é o gênero mais bem representado de algas vermelhas, com mais de 100 espécies reconhecidas e, além disso, se distribuem na maior parte dos mares tropicais e temperados do mundo. Desta forma, esse gênero destaca-se por ser a principal fonte mundial de ágar. O ágar é uma substância que pode ser extraído da parede celular de macroalgas desse gênero. Sua principal característica é a capacidade de formar um gel conhecido genericamente como ficocolóide. Este composto ao ser purificado pode ser utilizado em uma grande diversidade de produtos industriais, como no ramo alimentício, medicinal, cosmético, químico, farmacêutico, têxtil, dentre outras. O estudo teve como objetivo determinar o crescimento e a qualidade da macroalga Gracilaria birdiae cultivada na praia de Pau Amarelo em Pernambuco-Brasil durante o período seco e chuvoso, bem como a qualidade do ficocolóide ágar. O experimento foi dividido em 2 partes: uma realizada em campo (cultivo da macroalga) e a outra em laboratório (análise da qualidade da macroalga; extração de carotenóides e avaliação da qualidade do ágar). Ao comparar a biomassa total produzida nos períodos seco e chuvoso, valores superiores (p<0,01) foram observados para a estação seca (41,32 kg) em relação a chuvosa (13,36 kg). As taxas de crescimento relativo máximo obtido no final do cultivo no período seco foi de 7,52 %dia-1 e mínimo de 0,32 %dia-1, no período chuvoso de 5,33 e -2,64 %dia-1. Os parâmetros bromatológicos (g/100g) avaliados para os períodos seco e chuvoso respectivamente foram: umidade e substâncias voláteis (88,37 e 89,06%), proteínas (14,78 e 21,48%), cinzas (41,78 e 40,85%), lipídeos (5,33% e 4,20%), carboidratos (38,09% e 33,45%) e carotenóides totais (5,86 e 6,93 mg/mL). Os resultados demonstram que a macroalga apresenta grande desempenho para o cultivo em torno de 30 dias na região referida, boa qualidade bromatologica da macroalga e boa qualidade de dureza do ágar, dessa forma, podendo ser comercializada e utilizada para consumo humano.

Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-14Bitstream added on 2014-06-13T19:19:49Z : No. of bitstreams: 1 fermino_fs_dr_rcla.pdf: 1579925 bytes, checksum: 9575963e41a7425b9936cc27d8075a47 (MD5) / O estudo visou (a) identificar o nutriente limitante ao desenvolvimento do perifiton em escala sazonal no Lago das Ninfeias, (b) avaliar os principais atributos da comunidade indicadores desta limitacao, (c) caracterizar as principais alteracoes estruturais da comunidade de algas perifiticas frente ao enriquecimento artificial por nitrogenio e/ou fosforo e hierarquizar os fatores direcionadores dessas modificacoes. Foram realizados enriquecimentos isolados e combinado por N e P em represa rasa mesotrofica em quatro epocas do ano (primavera, verao, outono e inverno). Quatro tratamentos foram delineados utilizando substrato difusor de nutrientes (copos de poliestireno, preenchidos com solucao Agar e nutrientes . controle: sem adicao de nutrientes; N+: 0,75 M; P+: 0,05 M; NP+: adicao combinada dos dois sais, razao molar N:P = 15). A abertura dos copos foi revestida com malha de 20 um como substrato para o perifiton. Coletas foram realizadas aos 15o, 20o, 25o e 30o dias de colonizacao. A maior variabilidade dos dados limnologicos abioticos foi atribuida ao tipo de tratamento, seguida pela escala anual. A ACP indicou forte associacao entre a adicao de fosforo e, principalmente, adicao combinada com as maiores densidades de algas, clorofila-a e conteudo de fosforo do perifiton. O fosforo foi o nutriente limitante ao longo do ano e, dependendo do atributo, foi considerado como nutriente limitante, limitante primario ou co-limitado pelo nitrogenio. Exceto a massa organica, os demais atributos do perifiton foram bons indicadores da limitacao e a composicao quimica do perifiton foi decisiva na definicao desta limitacao. Foram encontrados 203 taxons, com maior representacao da classe Chlorophyceae. A riqueza especifica variou de 33 a 66 e sofreu maior influencia da epoca do ano. / Study aimed at (a) identifying the nutrient limitation to the development of algal periphyton in a seasonal scale at the Ninfeias Reservoir; (b) evaluating the main indicator community attributes of nutrient limitation; and (c) characterizing the main structural modifications underwent by the algal periphytic community caused by the artificial enrichment by nitrogen and/or phosphorus, as well as ranking the driven factors responsible for such modifications. Isolate and combined enrichments were carried out in a shallow, mesotrophic reservoir during four occasions (spring, summer, fall, and winter). Four treatments were designed using diffusing substrate (polystyrene vials filled with agar solution and nutrients . control: no nutrient addition; N+: 0.75 M; P+: 0.05 M; NP+: combined addition of N and P, molar ratio N:P = 15). Vial mouth was covered with a 20 um mesh cloth for periphyton colonization. Samplings were performed on the 15th, 20th, 25th, and 30th colonization days. The greatest abiotic limnological data variation was related to the kind of treatment, followed by the annual scale. PCA indicated a strong association between P and mainly combined P and N addition with the highest algal densities, chlorophyll a, and the P periphyton contents. Phosphorus was the limiting nutrient over the year, and depending on the periphyton attribute, it was either the only limiting nutrient, the primary limiting one, or colimited with N. Except for the organic mass, the remaining periphyton attributes were good nutrient limitation indicators, and periphyton chemical composition was conclusive in defining limitation. Two hundred and three taxa were identified, Chlorophyceae being the dominant algal class. Species richness varied from 33 to 66, being influenced mostly by the time of the year.

Made available in DSpace on 2014-06-11T19:30:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-05-16Bitstream added on 2014-06-13T21:01:48Z : No. of bitstreams: 1 silva_nml_dr_rcla.pdf: 1681735 bytes, checksum: 0eb84f1024cbb7b236e8ba041c6d5158 (MD5) / Os membros da ordem Trentepohliales são estritamente terrestres, crescendo em solo, rochas, troncos, folhas, frutos, folhas e vários tipos de construções artificiais. A ordem consiste de uma única família, Trentepohliaceae, e o número de gêneros é ainda conflitante entre os autores, alguns considerando a família com cinco gêneros (Trentepohlia, Printzina, Phycopeltis, Cephaleuros e Stomatochroon) e outros com seis (incluindo Physolinum, além dos gêneros citados). Esse grupo é um dos mais abundantes em ambientes terrestres e está entre os menos conhecidos e estudados, principalmente em regiões tropicais. Devido à sua morfologia relativamente simples, as Trentepohliales formam um grupo taxonomicamente difícil e sua grande plasticidade morfológica está relacionada a fatores ambientais, tornando confusa a distinção de espécies e gêneros. O presente estudo visou contribuir com o conhecimento taxonômico do grupo, por meio do levantamento florístico em cinco biomas brasileiros: Cerrado (Parque Nacional da Serra da Canastra e Parque Nacional da Chapada dos Veadeiros), Floresta Ombrófila Densa (Parque Estadual da Serra do Mar/Núcleo Picinguaba e Parque Nacional de Itatiaia), Floresta Ombrófila Mista (Região de Campos do Jordão) e Restinga (Parque Estadual da Serra do Mar/Núcleo Picinguaba), além de fragmentos de Floresta Estacional Semidecidual presentes na região noroeste do estado de São Paulo. Adicionalmente, objetivou-se a ampliação geográfica do registro de ocorrência das espécies já registradas em território nacional e descrição de aspectos ecológicos do habitat onde se desenvolvem. O material coletado foi utilizado para detalhamento da taxonomia do grupo, com a aplicação de estudos moleculares, além dos morfológicos clássicos. Os crescimentos de Trentepohliales... / Not available

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Lectinas de algas marinhas tÃm-se mostrado importantes ferramentas biotecnolÃgicas. Objetivou-se estudar as atividades antinociceptivas e antiinflamatÃrias da lectina da alga marinha vermelha Pterocladiella capillacea (Pc). A Pc, apresentando atividade hemaglutinante contra eritrÃcitos tripsinizados de coelho, foi obtida a partir da aplicaÃÃo do extrato protÃico total em cromatografia de troca iÃnica em coluna de DEAE-celulose seguida da cromatografia de afinidade em coluna de goma de guar. A seguir, foi utilizada nos ensaios de nocicepÃÃo e inflamaÃÃo, utilizando camundongos machos Swiss e ratos machos Wistar, respectivamente. Pc (0,9; 8,1 ou 72,9 mg/kg; i.v) foi administrada 30 min antes de cada estÃmulo nocigÃnico, ou seja, antes da injeÃÃo i.p de Ãcido acÃtico a 0,8% (10 &#956;L/mL), da injeÃÃo intraplantar de formalina a 1% (20 &#956;L/pata) ou do teste da Placa quente (51Â1 ÂC), e comparada a animais nÃo tratados ou prÃ-tratados com Indometacina ou Morfina, ambas a 5 mg/kg; s.c. Observou-se que a Pc (0,9; 8,1 ou 72,9 mg/kg) reduziu significantemente o nÃmero de contorÃÃes abdominais induzidas pelo Ãcido acÃtico em 29,2%; 39,3%, e 51,9%, respectivamente. Pc (72,9 mg/kg) tambÃm reduziu (p<0,05) a fase 1 (neurogÃnica) e a fase 2 (inflamatÃria) observadas apÃs administraÃÃo da formalina, em 58% e 87%, respectivamente. Entretanto, a Pc (72,9 mg/kg) nÃo foi capaz de reduzir a nocicepÃÃo observada no teste da Placa Quente, quando comparada à morfina. Os efeitos antinociceptivos da Pc foram abolidos quando a Pc foi prÃ-incubada com a glicoproteÃna mucina (1,25 mg/mL), inibidora de sua atividade hemaglutinante. Sugere-se, portanto, que a atividade antinociceptiva da Pc possa ser predominante via inibiÃÃo de mecanismos perifÃricos. Assim, seguiram-se os ensaios de induÃÃo da migraÃÃo neutrofÃlica para cavidade peritoneal ou do edema de pata de ratos por Carragenana (Cg-tipo l; 500 g/cavidade ou pata), onde observou-se que a administraÃÃo da Pc (8,1 mg/kg; i.v) 30 min antes da Cg reduziu significativamente a contagem do nÃmero de neutrÃfilos em 84%. No entanto, a Pc nÃo foi capaz de prevenir o edema de pata induzido pela Cg. Desta forma, sugere-se que esta proteÃna foi capaz de reduzir o mecanismo de migraÃÃo de neutrÃfilos, possivelmente ligando-se à molÃculas especÃficas celulares, como por exemplo, selectinas. Para confirmar sua seguranÃa, a PC (8,1 mg/kg) foi administrada em camundongos diariamente e no 7 dia foram coletadas amostras sanguÃneas para dosagens de urÃia e transaminases (TGO e TGP), e pesados rins e fÃgado. Observou-se que a Pc nÃo causou alteraÃÃes significativas, sugerindo portanto, ser segura no perÃodo de administraÃÃo avaliado. Dessa forma, considerando os dados em conjunto, conclui-se que a Pc possui propriedades antinociceptiva e antiinflamatÃria com aÃÃo perifÃrica. / Marine algae lectins had been showing important biotechnical tools. Our objectives were to study the antinociceptive and anti-inflammatory activities of the lectin from the marine red alga Pterocladiella capillacea (Pc). The Pc, presenting haemagglutinating activity against trypsin-treated erytrocytes from rabbit, was purified by application of crude extract (0.025 M Tris-HCl buffer, pH 7.5) on ion exchange chromatography on DEAE-cellulose followed by affinity chromatography on guar-gum column. To proceed, it was used in the nocicepÃÃo and inflammation assays, using male Swiss mice and male Wistar rats, respectively. Pc (0.9; 8.1 or 72.9 mg/kg; i.v) it was administered 30 min before each challenge, that is, before the injection i.p of acetic acid 0.8% (10 &#956;l/mL), of the intraplantar injection of 1% formalin (20 &#956;L/paw) or of the Hot Plate test (52Â1 ÂC), and compared to non treated animals or to pre-treated by Indomethacin or Morphine, both at 5 mg/kg; s.c. It was observed that the Pc (0.9; 8.1 or 72.9 mg/kg) reduced significantly the number of writhes induced by acetic acid (29.2%; 39.3%, and 51.9%, respectively). Pc (72.9 mg/kg) also reduced (p<0.05) the 1st phase (neurogenic) and the 2nd phase (inflammatory) observed after administration of the formalin (58% and 87%, respectively). However, the Pc (72.9 mg/kg) was not capable to reduce the nociception evaluated by Hot Plate test, compared to morphine. These antinociceptive effects were abolished when the Pc was pre-incubated with mucin (1.25 mg/mL), inhibitory glycoprotein of its haemagglutinating activity. Therefore, it is suggested that the antinociceptive activity of the Pc can be predominant by inhibition of peripheric mechanisms. After this, was realized the assays of neutrophil migration for peritoneal cavity or of the paw edema of mice by Carragenan (Cg-type l; 500 g/cavity or paw), where was observed that the administration of the Pc (8,1 mg/kg) 30 min before Cg reduced the neutrophil counts significantly by 84%. However, Pc was not capable to prevent the paw edema induced by Cg. This way, it is suggested that this protein was capable to reduce neutrophil migration by previous mechanism to migration, possibly linking to cellular specific molecules as, for example, selectins. Then, to confirm its safety, the Pc (8.1 mg/kg) was administered daily in mice and observed their behaviors, and at the 7th day, sanguine samples were collected for urea and transaminases (TGO and TGP) dosages, and heavy kidneys and liver. It was observed that Pc did not cause significant alterations, suggesting be safety for the administration period. Considering the data together, it is ended that the Pc possesses antinociceptive and anti-inflammatory properties with peripheral action.