Avaliação do efeito da luz e temperatura no crescimento in vitro de Ulva rigida C. Agardh (Chlorophyta, Chlorophyceae)

Dissertação de Mestrado em Biodiversidade e Biotecnologia Vegetal

Crescimento de Ulva rigida C. Agardh em condições de stress de macronutrientes

Dissertação de Mestrado em Biodiversidade e Biotecnologia Vegetal

Chemical composition of cultivated seaweed ulva clathrata (Roth) C. Agardh

Samples of cultivated Ulva clathrata were collected from a medium scale system (MSS, 1.5 1.5 m tank), or from a large scale system (LSS, 0.8 ha earthen pond). MSS samples were dried directly while the LSS sample was washed in freshwater and pressed before drying. Crude protein content ranged 20–26%, essential amino acids accounting for 32–36% of crude protein. The main analysed monosaccharides were rhamnose (36–40%), uronic acids (27–29%), xylose (10–13%) and glucose (10–16%). Some notable variations between MSS and LSS samples were observed for total dietary fibre (26% vs 41%), saturated fatty acids (31% vs 51%), PUFAS (33% vs 13%), carotenoids (358 vs 169 mg kg1 dw) and for Ca (9 vs 19 g kg1 ), Fe (0.6 vs 4.2 g kg1 ), Cu (44 vs 14 mg kg1 ), Zn (93 vs 17 mg kg1 ) and As (2 vs 9 mg kg1 ). The chemical composition of U. clathrata indicates that it has a good potential for its use in human and animal food.

Chemical and biological studies from an Azorean macroalga: Ulva rigida

3rd Portuguese Meeting on Medicinal Chemistry and 1st Portuguese-Spanish-Brazilian Meeting on Medicinal Chemistry, Aveiro, 28-30 Novembro 2012.

Gêneros Euastrum Ehrenberg ex Ralfs e Micrasterias C. Agardh (Conjugatophyceae-Desmidiaceae) de dois ambientes amazônicos de águas pretas (Manaus, Amazonas-Brasil)

Foi realizado um inventário das espécies dos gêneros Euastrum Ehrenberg ex Ralfs e Micrasterias C.Agardh de dois ambientes de águas pretas do munic��pio de Manaus, um lago de inundação (lago Tupé), e o rio Negro. As coletas foram realizadas com rede de plâncton em quatro estações no lago e uma no rio Negro, situada próxima ao lago. Um total de 93 amostras foi analisado, coletadas em escala mensal no período de março de 2002 a outubro de 2003. As espécies foram descritas e ilustradas com base na sua morfologia e morfometria. Um total de 12 espécies foi identificado, sendo cinco do gênero Euastrum (E. evolutum var. perornatum; E. gemmatum var. monocyclum; E. ornans; E. sinuosum e E. spinulosum), e sete do gênero Micrasterias (M. borgei; M. radiata var. brasiliensis; M. torreyi; M. laticeps var. acuminata; M. mahabuleshwarensis var. amazonensis; M. rotata var. rotata; M. siolii). Todas as espécies, exceto M. radiata Hassal var. brasiliensis Grönblad, foram registradas no rio Negro, enquanto no lago Tupé foi registrado, no geral, apenas sete espécies, três de Euastrum e quatro de Micrasterias.

Evaluación poblacional de Chondracanthus chamissoi (C. Agardh 1820) en las bahías de Pisco y Paracas, Otoño 2010.

Entre mayo y junio 2010, se desarrolló la evaluación poblacional de la macroalga Chondracanthus chamissoi “yuyo” de las praderas en las bahías de Pisco y Paracas. Las biomasas medias fluctuaron entre 2,2 y 67,0 g.m-2, con promedio de 43,6 g.m-2. Se estimó una biomasa total de 211,96 toneladas (±56,8%); de los cuales 179,74 t correspondieron a Atenas; 30,1 t a Puerto Nuevo y 2,1 t a Playa Lobería. El sustrato de fijación estuvo compuesto, principalmente, por piedras, conchuela y arena media. En las praderas de Atenas ocupó la mayor parte del área evaluada, en las praderas de Puerto Nuevo y Playa Lobería se encontraron reducidas, respecto al 2007. Se encontró ejemplares entre 1 y 25 cm de longitud. El peso total individual varió de 0,1 a 94,6 g. Se registró biodiversidad asociada conformada por moluscos. Las condiciones oceanográficas se registraron normales, lo que permite suponer que la disminución poblacional respondería a las actividades de extracción.

Cystoseira abies marina (Gmelin) C. Agardh (Phaeophyceae) en el Mediterraneo Iberico

Hs, MURCIA: Murcia, Cala del Burro, 29 m de profundidad, 3-VIII-1989, J. Soto and A. Gómez Garreta, BCF 6090, 6091. Dos ejemplares recolectados en el transcurso de una inmersión con escafandra autónoma.

Drought tolerance and light requirements of high and low sublittoral species of Mediterranean macroalgae of the genus Cystoseira C. Agardh (Fucales, Phaeophyceae)

Article sobre la tolerància a la sequera i les necessitats de llum d'espècies de l'alt i baix sublitoral de macroalgues de la Mediterrània del gènere Cystoseira C. Agardh (Fucales, Phaeophyceae)

The spreading of the introduced seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: testing the boat transportation hypothesis

The Spreading of the Introduced Seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: Testing the Boat Transportation Hypothesis

Corologia del genero Cystoseira C. Agardh (Phaeophyta, Fucales)

Se ha estudiado, basándose en una exhaustiva recopilación bibliográfica, la distribución mundial del género Cystoseira, que incluye una cincuentena de especies. Para cada especie se ha delimitado su área de distribución, lo que nos permite calcular el número de especies de este género existentes en las distintas áreas geográficas. El 80% de las especies de este género se encuentra en el Mediterráneo y Atlántico europeo y africano (desde Escocia a Cabo Verde), mientras que el 20% restante está distribuido en el mar Caribe, mar Rojo, oc��ano índico y oc��ano Pac��fico.

Effects of iron-ore particles on propagule release, growth and photosynthetic performance of Sargassum vulgare C. Agardh (Phaeophyta, Fucales)

The effect of iron-ore particles on the propagule release and growth of Sargassum vulgare C. Agardh was tested under treatments with different concentrations of iron-ore particles: 0.1, 1.0, 10.0 g.L-1 and a solution of 10.0 g.L-1 of filtered iron-ore. Filtered seawater was used as control. Photosynthesis vs. irradiance (P-I) curves were calculated for S. vulgare in the presence of iron-ore and in seawater. There was no significant difference in the number of propagules released by the receptacles or in the percentage of zygote formation among the treatments. The released propagules acted like aggregation centers for the particles, those more heavily coated with iron (10.0 g.L-1) exhibiting the highest sinking velocity (32.6 ± 9.8 mm.s-1). No difference in the percentage of embryo survival was detected during the first week in culture. After four weeks the embryos grew in all treatments. Maximum frond development (5.3 ± 0.8 mm) was observed in treatment of seawater enriched with Provasoli's medium (PES) while initial filoids did not develop in three treatments without PES and with iron-ore (0.1 g.L-1, 1.0 g.L-1 and 10.0 g.L-1). The values for Pmax, alpha and respiration showed no significant differences between the P-I curves. The calculated value for I K was 106.26 µmol.m-2.s-1 to the control curve and 981.49 µmol.m-2.s-1 to the iron-ore curve. The results indicate that the iron-ore particles in high concentration reduce the growth of S. vulgare as they recovered the embryos, juveniles and young plants. In contrast, the presence of the particles did not affect the release of gametes, percentage of zygote formation or the percentage of embryo survival.

Purificação e caracterização parcial de uma lectina da alga marinha vermelha Vidalia obtusiloba C. Agardh

A lectina da alga marinha vermelha Vidalia obtusiloba foi purificada através da combinação de precipitação com sulfato de amônio, cromatografia de troca iônica em DEAE-celulose e cromatografia de afinidade em goma de guar reticulada. A lectina preferencialmente aglutinou eritrócitos do grupo humano O, nativos e tratados com bromelaina. A atividade hemaglutinante revelou que a lectina era dependente de c��tions divalentes (Ca++ ou Mn++) e inibida por N-acetil-galactosamina, D-galactosamina, alfa-lactose and D-galactose e pela glicoproteína mucina de estômago de porco. A massa molecular da lectina, estimada por filtração em gel, foi de 78,9 kDa, enquanto por SDS-PAGE, em presença de beta-mercaptoetanol, a lectina exibiu duas subunidades protéicas diferentes com Mr de 59,6 e 15,2 kDa, sugerindo que a lectina é uma proteína dimérica. Focalização isoelétrica revelou a presença de uma proteína ácida simples, com um ponto isoelétrico entre 4 e 5. A lectina purificada exibiu um conteúdo de carboidrato de 43,2% e uma predominância dos aminoácidos Asp/Asn, Glu/Gln e Leu. A energia de ativação (deltaG') para a desnaturação da lectina foi calculada como sendo 25,4 kcalm.mol-1 a 90 ºC. Ensaios imunoquímicos usando um anti-soro de coelho produzido contra a lectina purificada de V. obtusiloba mostraram que foi possível detectar a presença da lectina em diferentes etapas do processo de purificação. Western blotting de géis de SDS-PAGE mostraram imunocoramento apenas da maior das subunidades da lectina.

Quantitative variables applied to phenological studies of Sargassum vulgare C. Agardh (Phaeophyceae - Fucales) from Ilha Grande Bay, State of Rio de Janeiro

The suitability of quantitative variables for phenological studies was evaluated in a population of the brown seaweed Sargassum vulgare from "Praia das Gordas", Angra dos Reis, Ilha Grande Bay, state of Rio de Janeiro. From June 1998 to May 1999, twenty adult individuals were randomly sampled at bimonthly intervals. Fifteen variables related to the vegetative and reproductive development of perennial and non-perennial parts of the individuals were quantified. Variables related to the non-perennial parts were more useful than those related to the perennial parts, because they showed a clear variation over the year. Vegetative development declined from June to October, and increased from October to February, when maximum median values of thallus height, total dry mass, non-perennial parts dry mass, and degree of branching were reached. This pattern coincided with those described for other species of the genus from warm temperate regions. Thallus height, a usually employed character in other phenological studies of Sargassum, showed lower coefficient of variation (53.2%) than those related to dry mass (72.0% to 182.3%). Peak of reproduction occurred from June to August, according to the following variables: fertile primary lateral branches number and dry mass and receptacles dry mass. Non-perennial parts dry mass and receptacles dry mass are recommended for phenological studies of S. vulgare. This methodological procedure avoids the sampling of the whole individual and warrants its regeneration from the perennial parts.

Sulfated bromophenols from Osmundaria obtusiloba (C. Agardh) R. E. Norris (Rhodophyta, Ceramiales)

Two new sulfated oligobromophenols from the marine red algae Osmundaria obtusiloba, 4-(1'-potassium sulfate, 2,3-dibromo, 1',4,5-trihydroxybenzyl) - 4''-(1'''-potassium sulfate, 2'',3''-dibromo, 1''',4'',5''-trihydroxybenzyl) sulfate and 1'-(2, 3-dibromo, 4-potassium sulfate, 1', 4, 5-trihydroxybenzyl) - 4''-(1''' potassium sulfate, 2'', 3''-dibromo, 1''', 4'', 5'' trihydroxybenzyl) sulfate, are herein reported. Besides them it was obtained 2, 2', 3, 3'-tetrabromo-4, 4', 5, 5'-tetrahydroxydiphenylmethane, 2, 3-dibromo-p-hydroxybenzyl methyl ether (methyl lanosol), dipotassium 2,3-dibromo-5-hydroxybenzyl 1',4-disulfate, 24-methylenecolest-5-en-3-beta-ol and alpha-D-mannopyranosyl-(1->2')-glycerate (digeneaside). The structures were determined by analysis of the spectroscopic data (IR, NMR and MS) and comparison with the literature. The 13CNMR data for dipotassium 2,3-dibromo-5hydroxybenzyl-1',4-disulfate are described here for the first time. The present study also suggests a mild method to isolate and to purify sulfated compounds.