The genus Fucus (Phaeophyceae) has nine commonly accepted species, six of which inhabit North American shores: F. gardneri, F. serratus, F. distichus, F. evanescens, F. vesiculosus, and F. spiralis. Fucus inhabit the intertidal zones of the Atlantic, Pacific and Arctic Oceans and due to their highly plastic and morphologically simple phenotypes, are valuable candidates for molecular phylogenetic research. Furthermore, Fucus species are valuable for biogeographic investigations due to their relatively slow migration, limited dispersal range, and easily collected distribution. The closest ancestral species to the genus is a Pacific endemic Hesperophycus californicus supporting a North Pacific origin of the species (Serrão et al. 1999). However, a closer relationship between Atlantic and Arctic Fucus has been described casting doubt on the Pacific origins of the genus (Lindstrom 2001, Dunton 1992). The investigation of Fucus across this area is necessary to elucidate the apparent contradiction in the origin of the genus. Samples were collected from 79 locations across North American waters. The amplification of the divergent mtDNA spacer region was performed to assess taxonomic placement of 55 collected species and reconstruct the biogeography of North American Fucus species. Morphological analysis was also completed based on 21 measured characteristics in an attempt to support molecular analysis. Results of the study indicate two distinct lineages among collected samples. One lineage (F. spiralis and F. vesiculosus) with a distinct Atlantic origin and the second lineage (F. distichus and F. serratus) with a widely distributed F. distichus, and the Atlantic F. serratus. Morphological analysis and statistical support for these lineages was determined through discriminant analysis of the collected samples. Overall results determined biogeographic influences in the F. distichus species complex across Arctic, Pacific, and Atlantic regions with little apparent biogeographical influence within F. vesiculosus, F. serratus and F. spiralis. Closer phylogenetic relationships between Arctic and Atlantic samples were apparent as suggested by Lindstrom (2001) and Dunton (1992).

En milieu intertidal rocheux, les communautés dominées par des canopées d'algues brunes (Phaeophyceae) sont particulièrement répandues. Malgré leur accessibilité, leur fonctionnement reste encore largement méconnu. En particulier, l'influence de la saisonnalité et du gradient d'émersion sur le métabolisme, le réseau trophique ou encore le processus de succession a été peu étudiée. Ce travail de thèse a donc eu pour objectif d'analyser le fonctionnement de deux communautés de Fucus établies à des niveaux marégraphiques différents, en portant une attention particulière aux conditions environnementales. Sur les côtes bretonnes (France), les communautés de Fucus vesiculosus Linnaeus et de Fucus serratus Linnaeus sont respectivement caractéristiques des étages médiolittoral moyen et inférieur. Des mesures de métabolisme (production primaire et respiration) réalisées in situ à différentes périodes de l'année ont mis en évidence une forte influence de la saisonnalité et le rôle primordial de la canopée dans les flux de carbone. Le métabolisme s'est avéré être plus élevé à l'émersion qu'à l'immersion, où l'intensité lumineuse constitue régulièrement un facteur limitant pour la production primaire. Par une approche de modélisation basée sur ces mesures et sur des données environnementales acquises à haute fréquence, un bilan annuel de production primaire a été calculé pour chaque communauté. Ces bilans confirment que ces systèmes sont fortement productifs et permettent de préciser leur régulation à l'échelle des cycles de marées. Le réseau trophique de ces communautés, analysé via les isotopes stables du carbone et de l'azote, apparait basé sur l'utilisation de nombreuses sources. / Along intertidal rocky shores, communities dominated by canopy-forming brown algae (Phaeophyceae) are particularly widespread. Their functioning is however largely understudied, especially concerning the influence of seasonality and shore height on primary production and respiration, on food webs or on successional process. The aim of this study was to investigate the functioning of two intertidal Fucus communities which are established at different tidal levels. During this study, a special consideration was given to the effects of environmental conditions. On the coasts of Brittany (France), communities dominated by Fucus vesiculosus Linnaeus and Fucus serratus Linnaeus are characteristic of mid-intertidal and low mid-intertidal levels, respectively. In situ measurements of metabolism (primary production and respiration) carried out at different periods of a year highlighted a strong seasonal influence on carbon fluxes and emphasized the importance of canopies in the metabolism of whole communities. Metabolism was higher during emersion than during immersion periods, for which light intensity regularly limits the primary production. Based on these measurements and on high-frequency measurements of environmental parameters, an annual primary production was calculated by modelling for both communities. These annual estimations confirmed that these communities are among the most productive systems of coastal region and specify their regulation at the tidal cycles scale. Food webs, which were analysed through carbon and nitrogen stable isotopes, are based on the use of almost all available sources of organic matter by consumers, and revealed a strong conservation of food webs across seasons. Thecolonisation survey of bare substrates shows that Fucus species improve the settlement success of numerous species and increase rapidly primary production of whole assemblages. Overall, despite some differences in metabolism and successional sequences according to the shore height at whichthey are located, these communities exhibited similar functioning due to the canopy which damns the environmental conditions.

Eutrophication due to enhanced nutrient concentrations can affect marine communities by altering the species composition of macroalgae and marine invertebrates, where certain species have shown tendencies to increase. The aim with this study was to assess how the species composition changed in relation to the distance from a nutrient enriched stream discharge. The study was conducted in an area with rocky shores and Fucus vesiculosus as the dominant alga, and also included the mouth of the eutrophic stream Kvarnabäcken. Macroalgae and invertebrate abundance was examined in eight locations (including an unaffected reference location) at different distances from the mouth of Kvarnabäcken. The concentrations of total nitrogen and total phosphorus were measured in the marine locations as well as in the stream. Although Kvarnabäcken displayed elevated nutrient concentrations, no distinct nutrient gradient was detected in the marine locations due to distance from the stream. The abundance of invertebrates and macroalgae varied to some extent in the locations, where the location in the immediate mouth area showed most differences, which contributed to the conclusion that the direct impact of nutrient discharge is limited. Although there are aspects indicating that the alterations in animal and algae abundance are consequences of nutrient discharge, other factors that regulate community composition must be considered when evaluating eutrophication in marine communities. / Övergödning kan påverka marina samhällen genom att artsammansättningen av makroalger och marina evertebrater ändras till följd av förhöjda närsalter, bland annat genom att vissa arter tenderar att öka i förekomst. Syftet med denna studie var att undersöka om artsammansättningen av marina evertebrater förändrades i relation till avståndet från ett utsläpp från en bäck med förhöjda närsaltkoncentrationer. Studien utfördes i ett område med klippiga stränder och Fucus vesiculosus som den dominerande algen och inkluderade även mynningen av den övergödda bäcken Kvarnabäcken. Förekomst av makroalger och evertebrater undersöktes i åtta lokaler (en opåverkad referenslokal inkluderad) längs kusten på varierande avstånd från bäcken. Koncentrationerna av totalkväve och totalfosfor mättes i de marina lokalerna och i bäcken. Trots att Kvarnabäcken visade höga halter av närsalter, visade inte resultatet någon tydlig näringsgradient från bäcken, medan det fanns en antydan till förändrad förekomst av evertebrater och alger i lokalerna. Lokalen närmast utsläppet skiljde sig något från övriga, vilket kan indikera att den direkta påverkan av näringstillförsel kan vara begränsat. Därtill är det viktigt att understryka att även om skillnader i förekomst av evertebrater och alger i lokalerna kan bero på närsalter från bäcken måste övriga faktorer tas hänsyn till vid undersökningar av marina samhällen.

No description available.

Made available in DSpace on 2014-12-17T14:03:45Z (GMT). No. of bitstreams: 1 MariaLC.pdf: 493490 bytes, checksum: ba60f2812dd358a875dfd794b36dacc3 (MD5) Previous issue date: 2007-06-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The fucoidan from Fucus vesiculosus is known for having diverse biological properties. This study analyzed the therapeutic action of populations of commercial fucoidan (F. vesiculosus) on zymosan-induced arthritis. Three populations of fucoidan were obtained after acetone fractionation; these were denominated F1 (52.3%), F2 (36.7%) and F3 (10.7%). Chemical analyses showed that F1 contained the largest amount of sulfate ion. The electrophoretic profile shows that the commercial or total fucoidan (TF), different from the other fucoidans and from glycosaminoglycan patterns, is quite polydisperse, which indicates that it is composed of a mixture of sulfate polysaccharides. On the other hand, the fucoidans obtained from TF showed only an electrophoretic band with much lower polydispersion than that observed for TF. Fucoidan F2 showed a migration between fucoidans F1 and F3. Owing to the small amount of mass obtained from F3, we used only fucoidans F1 and F2 in the induced arthritis tests. After 1 hour of induction, we administered F1 or F2 (10, 25 and 50 mg/kg i.p.) or diclofenac sodium (10 mg/kg i.p.) or lumiracoxib (5 mg/kg o.a.) or L-NAME (30 mg/kg i.p.). After 6 hours, we performed analyses of cell influx and nitrite levels in addition to histopathological analysis. Fucoidans F1 and F2 were more potent both in decreasing the number of leukocytes and the amount of nitric oxide found in the synovial fluid. This indicates that the anti-inflammatory mechanism of these fucoidans is not only related to selectin block, but also to nitric oxide synthesis inhibition / A fucoidana de Fucus vesiculosus ? conhecida por exibir fun??es biol?gicas diversas. Este trabalho analisou a a??o terap?utica de popula??es obtidas da fucoidana comercial (F. vesiculosus) no modelo de artrite induzida por zymosan. Ap?s fracionamento com acetona obteve-se tr?s popula??es de fucoidana que foram denominadas de fucoidanas F1 (52,3%), F2 (36,7%) e F3 (10,7%). As an?lises qu?micas demonstraram que F1, dentre as fucoidanas obtidas, foi a que apresentou a maior quantidade do ?on sulfato. O perfil eletrofor?tico mostra que a fucoidana comercial ou total (FT), diferente das outras fucoidanas e dos padr?es de glicosaminoglicanos, se mostrou bastante polidisperso, o que indicou que essa ? constitu?da por uma mistura de polissacar?deos sulfatados. Por outro lado, as fucoidanas obtidas a partir de FT mostraram apenas uma banda eletrofor?tica com uma polidispers?o bem menor do que aquela observada para FT. A fucoidana F2 apresentou uma migra??o intermedi?ria entre as fucoidanas F1 e F3. Devido a pequena quantidade de massa obtida de F3, utilizou-se apenas as fucoidanas F1 e F2 nos ensaios da artrite induzida. Ap?s 1 hora da indu??o foram administradas F1 ou F2 (10, 25 e 50 mg/Kg i.p) ou diclofenaco s?dico (10 mg/Kg i.p) ou lumiracoxibe (5 mg/Kg v.o) ou L-NAME (30 mg/Kg i.p). Ap?s 6 h, foram realizadas as an?lises do influxo celular e n?veis de nitrito e a an?lise histopatol?gica. As fucoidanas F1 e F2 foram mais potentes tanto na diminui??o do n?mero de leuc?citos, quanto na quantidade de oxido n?trico encontrado no lavado. O que indica que o mecanismo antiinflamat?rio dessas fucoidanas n?o est? s? relacionado com o bloqueio das selectinas, mas tamb?m com a inibi??o da s?ntese do oxido n?trico

No description available.

The morphology, distribution, and habitat of dwarf and normal forms of Fucus distichus in Nehalem Bay were examined. The dwarf form lacked the holdfast and sexual structures of the normal form and was more highly branched. Examples of the dwarf form were found growing as outgrowths of fragmented normal forms indicating that both forms are the same species. The normal form occurred attached to rocks near the mouth of the bay in waters of oceanic salinity. The dwarf form occurred as a free-living form in the salt marshes and in waters of lower salinity. These observations suggested that the occurrence of the dwarf form is related to salinity. Nutrient uptake studies with nitrate and carbon demonstrated that both forms have similar responses to changes in salinity. The dwarf form however, was better adaptated to the lower salinities than the normal form. Both forms showed a drop in carbon uptake and a slight rise in nitrate uptake as salinity was decreased, but the dwarf form maintained near maximal carbon uptake rates to a much lower salinity. It was shown that carbon uptake is sensitive to sodium and potassium ions, and nitrate uptake is sensitive to potassium ions. Reducing the sodium ion concentration by changing the medium composition decreased the carbon uptake rate. This rate was reduced further by the addition of potassium ion. The addition of sodium and potassium specific ionophores to the medium also depressed the uptake rate of carbon. Nitrate uptake was relatively unaffected by decreased sodium concentrations, but was drastically reduced by elevated potassium levels. The potassium specific ionophore valinomycin also produced a significant drop in the nitrate uptake rate. These data suggested that chemical potentials for sodium and potassium drive the uptake of carbon and that potassium is involved in the uptake of nitrate in F. distichus.

Une perte de poids modérée peut contribuer à prévenir le diabète de type 2 chez les personnes en surpoids/obèses. Certaines études in vitro et in vivo montrent que les algues brunes riches en polyphénols ont le potentiel de contrôler le métabolisme glucidique. Mais l’effet combiné de ces deux stratégies chez l’humain est peu étudié. Cette étude évalue l’effet d’un extrait d’algues brunes riche en polyphénols (InSea2®) combiné à une intervention nutritionnelle individualisée visant une perte de poids modérée sur l’homéostasie du glucose chez des sujets pré-diabétiques en surpoids/obèses avec hyper-insulinémie (insuline à jeun > 60 pmol/L). Le devis expérimental utilisé est randomisé, en double aveugle, en bras parallèles avec groupe placebo. Deux traitements ont été administrés: Traitement 1 avec placebo + déficit modéré de l’apport calorique quotidien et Traitement 2 incluant 500 mg d’algues brunes + déficit modéré de l’apport calorique quotidien. Cinquante-six sujets, hommes et femmes, âgés de 18-70 ans ont participé à l’étude qui a duré 12 semaines. Les apports alimentaires ont été estimés à partir d’un Questionnaire de Fréquence Alimentaire auto-administré et validé. Une perte de poids (p<0,0001) et de gras (p<0,0001) corporels est observée dans les deux groupes, mais sans différence entre les groupes. Une baisse significative du taux de cholestérol des LDL (p<0,05), des battements cardiaques (p<0,01), du C-peptide au temps 120 min durant un test de tolérance au glucose (p=0,002) et une inhibition de la hausse du marqueur pro-inflammatoire IL-6 (p<0,02) ont été observées dans le groupe traité comparativement au groupe placebo. Aucune différence n’est observée concernant la glycémie, l’insuline et le C-peptide à jeun. En conclusion, la consommation de l’extrait d’algues brunes peut améliorer l’homéostasie du glucose, le profil lipidique, les battements cardiaques et le statut inflammatoire chez les personnes obèses prédiabétiques. / Moderate weight loss can help prevent type 2 diabetes in overweight/obese subjects. Some in vitro and in vivo studies show that brown algae rich in polyphenols have the potential to control carbohydrate metabolism. However, the combined effect of these two strategies in humans has been little studied. The objective of this study was to evaluate the effect of a brown algae extract rich in polyphenols (InSea2®) combined with an individualized nutritional intervention aimed at moderate weight loss on glucose homeostasis in prediabetic overweight/obese subjects with hyperinsulinemia (fasting insulin > 60 pmol/L). The experimental design used was randomized, double blind and in parallel arms with the placebo group. Two treatments were administered: Treatment 1 with placebo + moderate deficit in daily caloric intake and Treatment 2 including 500 mg of brown algae + moderate deficit in daily caloric intake. A total of 56 subjects, men and women, aged 18-70 years participated and completed the 12-week study. Food intake was estimated from a validated Self-administered Food Frequency Questionnaire. Weight loss (p <0.0001) and body fat (p<0.0001) were observed in the two groups but no difference was noted between the groups. A significant drop in LDL cholesterol (p<0.05), heartbeat (p<0.01), C-peptide at 120 min during a glucose tolerance test (p=0.002) and inhibition of the rise in the proinflammatory marker IL-6 (p<0.02) were observed in the group treated with brown algae extract compared to the placebo group. There were no differences in fasting blood glucose, insulin and C-peptide. In conclusion, the consumption of brown algae extract can improve glucose homeostasis, and related parameters such as lipid profile, heartbeat and inflammatory status in obese pre-diabetic subjects

The nutrition bound in macroalgae, also known as seaweed, contains high amounts of all the nutrients, micronutrients, vitamins and plant hormones, necessary for plants, animals and humans. Totally for free it is floating in the oceans around the world and has been harvested and used by people for thousands of years. A problem that has arisen in the wake of Industrialism during the past 200 years is that human beings spread non-desirable substancesto air, water and soil, for example heavy metals. Macroalgae accumulate the heavy metals, which may become a problem if we want to eat seaweed or use it to grow plants in.  In a growth trial using macroalgal compost made from Fucus radicans collected from the Baltic Sea, the uptake heavy metals in the edible tubers of potatoes of the cultivar ‘Cherie’ was investigated. The following heavy metals were analyzed: lead(Pb), cadmium (Cd), mercury (Hg), arsenic (As) and copper (Cu). There were no differences in the uptake of heavy metal between potatoes grown in macroalgal compost and soil, but the potato tubers from both cultivations contained concentrations of Cd and As higher than those normally found in Swedish potatoes. The concentrations are, however, much lower than the limits set by EFSA. The macroalgal compost and the soil used in the experiment were also analyzed for heavy metal content. The Cd concentration in the compost exceeded the limit for Swedish compost. However, the high levels of Cd in the compost were not reflected in the Cd content of the potato tubers. Soil conductivity and pH values were also investigated. The high conductivityof the macroalgal compost was probably due to insufficient rinsing of the macroalgae, and thus it was not ideal for use in crop cultivation. In spite of this, the crop yield was good. In conclusion, macroalgal compost can be recommended as a cultivation substrate for potatoes. / Den näring som finns bunden i makroalger, även kallad tång, innehåller rikliga mängder av alla näringsämnen, spårämnen, vitaminer och växthormoner som växter, djur och människor behöver. Alldeles gratis flyter den omkring i världshaven och har skördats och använts av människan under tusentals år. Problemet som uppstått i industrialismens spår de senaste 200 åren är att människan sprider icke önskvärda ämnen till luft, vatten och jord, t.ex. tungmetaller. Makroalger ackumulerar dessa, vilket kan bli ett problem om vi vill äta eller odla i tång.  Vid ett odlingsförsök med potatis i tångkompost av Fucus radicans från Östersjön undersöktes metallupptaget i de ätbara knölarna i potatis av sorten ’Cherie’. De tungmetaller som analyserades var bly (Pb), kadmium (Cd), kvicksilver (Hg), arsenik (As) och koppar (Cu). Analysrapporten visade ingen skillnad i upptag av tungmetaller mellan potatis som odlats i tångkompost eller i jord; däremot innehöll knölarna från båda odlingarna högre halter av kadmium och arsenik än normalvärdena i svensk potatis. Halterna är dock långt under EFSA:s gränsvärden. Även odlingssubstraten, dvs. tångkomposten och jorden undersöktes för tungmetallförekomst. Kadmiumhalterna i tångkomposten översteg gränsvärdet för svenska kompostjordar, men de höga kadmiumhalterna reflekterades inte i potatisknölarnas kadmiuminnehåll. Odlingssubstratens ledningstal och pH-värden undersöktes också. Tångkompostens höga ledningstal (10,8 mS/cm) berodde antagligen på otillräcklig sköljning och gjorde den inte idealisk för odling. Trots detta blev skördeutfallet gott. Således kan tångkompost rekommenderas som odlingssubstrat för potatis.

Made available in DSpace on 2014-12-17T14:03:43Z (GMT). No. of bitstreams: 1 CarolineACX.pdf: 623551 bytes, checksum: 6aed4455120c14dc04af31815ec90ea1 (MD5) Previous issue date: 2005-10-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Rheumatoid arthritis (RA) is systemic auto imune disorder. It is caracterized by chronic inflammation of joints leading to progressive erosion of cartilage and bone. We investigated the effect of the administration of fucoidan, sulfated polysaccharides, from algae Fucus vesiculosus in the acute (6h) in zymosan-induced arthritis (AZy). Wistar rats (180-230 g) were used for all groups experimental. Non-treated animals received just intraarticular injection of 1 mg the zymosan, control group received intraarticular injection of 50 ?L the saline, groups received either fucoidan of Fucus vesiculosus (15, 30, 50 or 70 mg/Kg) or parecoxib (1 mg/Kg) 1 hour after injection of zymosan. After 6 h, the articular exudates were collected for evaluation of the cell influx and nitrite (Griess reaction) release. The sinovial membranes and articular cartilages were excised for histopathological analysis and by determination of the glycosaminoglycan (GAG), respectively. ZyA led to increased NO and cell influx into the joints. Therapeutic administration of the fucoidan or parecoxib did significantly inhibited the cell influx and the synovitis, as compared to non-treated rats (p<0,05), though being able to reduced NO release. Representative agarose gel electrophoresis of the GAGs, the content of condroitin-sulphate was observed during the process. These findings suggest that the fucoidan from Fucus vesiculosus has potential anti-inflammatory activity / A artrite reumat?ide (AR) ? uma doen?a auto-imune sist?mica, caracterizada por inflama??o cr?nica das articula??es, resultando em progressiva eros?o cartilaginosa e ?ssea. Neste trabalho foi investigado o efeito da administra??o do fucoidam, polissacar?deos sulfatados, da alga marinha Fucus vesiculosus na fase aguda (6h) da artrite induzida por zymosan (AZy). Ratos Wistar (180-230 g) foram utilizados para todos os grupos experimentais. Animais n?o tratados receberam apenas 1 mg de zymosan intraarticular (i.a), o grupo controle recebeu 50 ?L de solu??o salina intraarticular (i.a.), os outros grupos receberam fucoidam de Fucus vesiculosus (15, 30, 50 ou 70 mg/Kg,) ou parecoxib (1 mg/Kg), por via intraperitoneal (i.p.) 1 hora ap?s a inje??o de zymosan (i.a.). Ap?s 6 h, o exsudato articular foi coletado para an?lises do influxo celular e libera??o de nitrito (reagente de Griess). As membranas sinoviais e as cartilagens articulares foram retiradas para an?lises histopatol?gicas e para a determina??o dos glicosaminoglicanos, respectivamente. A AZy caracterizou-se por libera??o aumentada de NO e influxo de c?lulas inflamat?rias, nas juntas. A administra??o terap?utica do fucoidam ou parecoxib inibiu (p<0,05) o influxo celular, a libera??o de ?xido n?trico e a sinovite, comparado ao grupo n?o tratado. Por eletroforese em gel de agarose e tamp?o PDA 0,05M pH9,0 foi observado bandas com migra??es semelhantes ao condroitim sulfato (CS). Estes resultados sugerem que o fucoidam de Fucus vesiculosus tem um potencial anti-inflamat?rio