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Los fucoidanos de muchas especies de algas han sido investigados debido a su actividad biológica. Aunque la relación entre estas bioactividades y la estructura de los fucoidanos aún no se ha dilucidado, se ha demostrado que la composición de los monosacáridos, el contenido y distribución de los ésteres de sulfato y el peso molecular juegan un papel fundamental. El objetivo de este trabajo es realizar una evaluación de cuatro especies de algas pardas de las costas del Golfo Nuevo, como fuentes de fucoidanos. Para ello, tejidos secos de Myriogloea major, Eudesme virescens, Colpomenia sinuosa y Asperococcus ensiformis fueron sometidas al mismo protocolo de extracción. Se compararon rendimientos, composición de monosacáridos, contenido de azúcares, sulfatos, ácidos urónicos y proteínas. Los resultados sugieren que M. major puede ser una fuente de fucoidanos, se escogió uno de sus extractos para realizar su fraccionamiento y, en el futuro, avanzar con su elucidación estructural.

The invasive brown seaweed Undaria pinnatifida was first recorded in 1992 in Golfo Nuevo, northern Patagonia, Argentina (hereafter Undaria). Like other brown seaweeds, Undaria synthesizes fucoidans, a unique class of sulfated polysaccharides, which display an array of biological activities and have important commercial value. In this work we have measured the content, sulfate, and monosaccharide composition of fucoidans in Undaria sporophylls from Golfo Nuevo. These results were analyzed in relation to harvest month and development stage of algal thalli. Samples were collected between November 2015 and March 2016 and classified according to morphological traits into previously defined development stages. Acid extraction (0.01 M HCl, pH 2) was carried out at room temperature and at 70 °C. Average fucoidan content was 18.1% dry wt. and slightly increased with month progression and in senescent individuals. Average sulfate content in fucoidan extracts was 20.3% dry wt. decreasing with month and development. Predominant sugars were fucose and galactose averaging a total of 91 mol% of neutral sugars. This study confirms that sporophyll fucoidans from Patagonian Undaria are sulfated galactofucans. Fucoidan content significantly increases from 14.5 to 19.2% dry wt. with sporophyte development. Slight increments with month progression are not statistically significant. Molar proportion of neutral sugars is constant between maturity stages and varies slightly with month progression. Sulfate content of fucoidan decreased significantly with development and month progression. Pooled with previous reports about abundance and seasonality of Undaria in Patagonia, our results suggest that sporophylls could be harvested for fucoidan production at least during 5 months between November and March.

Dye-sensitized solar cell (DSSC) technology represents a valuable source for renewable energy production. Although with a rather low conversion efficiency, the continuous improvement of the price/performance ratio is making this technology more competitive than other sources of electrical power generation. To date, one of the major challenges is the search of novel and low-cost photosensitizers, a key player in the overall photo-conversion process. Natural dyes have shown to be an excellent alternative that still needs to be further explored. In this work, the spectroscopic and electrochemical properties of two different families of naturally occurring pigments (i.e, β -carboline alkaloids ( β Cs) and the red protein R-phycoerythrin (R-PE)) as well as their role in DSSCs are addressed. DSSC assemblies show that R-PE represents a highly suitable photosensitizer showing quite a high stability with a relative high solar energy to electricity conversion efficiency ( η = 0 . 11 %) when comparing with other recombinant proteins ( η = 0 . 30 %). Algae extracts used without further purification showed herein the highest efficiencies. The latter fact has a concomitant positive effect on the overall production cost of these photovoltaic cells. Surprisingly, and despite their positive effect on the coating of the semiconductor surface, the use of β Cs as additive decreases the overall conversion efficiency of the R-PE based DSSCs evaluated. Data support the hypothesis these alkaloids would be blocking the incident UVB/UVA radiation.

At mid-latitudes, sea water temperature shows a strong seasonal cycle forced by the incident surface heat flux. As depth decreases, the heat flux incidence is damped by the horizontal flux, which prevents the indefinite growth of the seasonal temperature range. In the present work, cross-shore transport in the west coast of Nuevo Gulf (Argentina) was analyzed. Processes tending to cool the coastal waters in summer and to warm the coastal waters in winter, were identified through temperature measurements, surface heat flux and tidal height. The simplified models proposed here provide a feedback mechanism that links changes in surface heat flux with changes in the horizontal heat flux during both seasons. On shorter time scales, tide produces significant variations in the height of the water column, therefore influencing temperature fluctuations and the direction of the horizontal flow. Fil: Rivas, Andres Lujan. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Pisoni, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Dellatorre, Fernando Gaspar. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Tecnológica Nacional; Argentina

Little is known about the bulk hydrogen stable isotope composition (δ2H) of seaweeds. This study investigated the bulk δ2H in several different seaweed species collected from three different beaches in Brazil, Australia, and Argentina. Here, we show that Ulvophyceae (a group of green algae) had lower δ2H values (between −94? and −130?) than red algae (Florideophyceae), brown algae (Phaeophyceae), and species from the class Bryopsidophyceae (another group of green algae). Overall the latter three groups of seaweeds had δ2H values between −50? and −90?. These findings were similar at the three different geographic locations. Observed differences in δ2H values were probably related to differences in hydrogen (H) metabolism among algal groups, also observed in the δ2H values of their lipids. The marked difference between the δ2H values of Ulvophyecae and those of the other groups could be useful to trace the food source of food webs in coastal rocky shores, to assess the impacts of green tides on coastal ecosystems, and to help clarify aspects of their phylogeny. However, reference materials for seaweed δ2H are required before the full potential of using the δ2H of seaweeds for ecological studies can be exploited. Fil: Carvalho, Matheus C.. Southern Cross University; Australia Fil: Carneiro, Pedro Bastos de Macedo. Universidade Federal do Ceará; Brasil Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Tecnológica Nacional. Facultad Regional Chubut; Argentina Fil: Gibilisco, Pablo Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia; Argentina Fil: Sachs, Julian. University of Washington; Estados Unidos Fil: Eyre, Bradley D.. Southern Cross University; Australia

The purpose of the present work was to study lipid content and fatty acid profile in fifteen macroalgal species typical of the coastal environments of northern Patagonia, Argentina. Total lipid content was observed to range between 2 and 12% of dry biomass, reaching an average of 7‐–12% in some abundant and globally distributed species, such as Ulva spp., Codium spp., Ceramium virgatum, and Undaria pinnatifida. Total fatty acid content was found to exceed neither 3% of dry biomass nor 30% of total lipids in any of the species studied. Polyunsaturated fatty acids (PUFAs) were dominant in all the brown species under study, particularly in the sporophyll of U. pinnatifida. Ceramium virgatum and Ulva sp. (tubular enteromorphoid thallus) were also rich in PUFAs. Essential fatty acids (linoleic acid and α-linolenic acid) and other valuable long-chain PUFAs, such as eicosapentaenoic acid, stearidonic acid, and arachidonic acid, were abundant in these species, arachidonic acid reaching up to 10 mg g−1 in U. pinnatifida sporophyll. In contrast, docosahexaenoic acid was only recorded at trace levels. Taken together, the results from the present study lead to conclude that the high levels of lipid content are indicative of potential applications of some of the most abundant species in the Patagonian coasts as biomass feedstock for lipid-based bioproducts. In line with this conclusion, eicosapentaenoic, stearidonic and arachidonic acid from the species studied could, in particular, be used for nutritional and nutraceutical purposes.

There is a growing interest about using natural polymers from renewable sources as biomaterials for applications in tissue engineering. In the present work, alginates were extracted from Undaria pinnatifida, a brown sea weed invasive in Argentinian coast. The isolated alginate was structurally characterized by IR and 1H NMR spectroscopies, intrinsic viscosity and TGA. For comparison purposes, commercial sodium alginate was purified and characterized using the same protocol as for raw material. Toxicity and biocompatibility of sodium alginate obtained from algae were studied using a murine macrophage-like cell line (RAW 264.7) and bone marrow stromal cells (BMSC), respectively. The presence of impurities inhibited both RAW 264.7 and bone marrow stromal cell proliferation and increased nitric oxide production from macrophages, while inhibited osteoblastic differentiation of BMSC. All these effects were reverted by the purification of alginate. In conclusion, alginate purification improves biocompatibility and osteo-induction while decreases its toxicity. Fil: Torres, María Luz. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Fernandez, María José. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra Bioquímica Patológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Grupo de Investigación y Desarrollo Tecnologico En Acuicultura y Pesca. - Universidad Tecnologica Nacional. Facultad Regional Chubut. Grupo de Investigacion y Desarrollo Tecnologico En Acuicultura y Pesca.; Argentina Fil: Cortizo, Ana María. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra Bioquímica Patológica; Argentina Fil: Oberti, Tamara Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina

In species with meroplanktonic larval phases, some reproductive traits (i.e. seasonality and larval behaviour) interact with hydrographic features to determine larval transport. This work reports the seasonal, diel and ontogenetic changes in vertical distribution of crab larvae in the boundary region between the Argentine and the Magellanic biogeographic provinces of the Atlantic coast off northern Patagonia (Golfo Nuevo; 42.75°S, 65.00°W). Larval seasonality was studied from 47 plankton hauls taken from August 2004 to July 2005. Vertical distribution was studied from 45 stratified plankton hauls carried out in August 2005, December 2005 and April 2006. Crab larval stages were detected throughout the year, but abundance was higher from midwinter to midsummer. Species from southern regions – Munida gregaria, Peltarion spinosulum and Halicarcinus planatus – were abundant during winter and aggregated mainly near the surface, regardless of the hour of the day. In contrast, species from northern regions – Platyxanthus patagonicus, Ovalipes trimaculatus, Leucippa pentagona, Leurocyclus tuberculosus, Cyrtograpsus spp. and Pachycheles chubutensis – were abundant during spring and summer and were usually aggregated near the surface during the night and dispersed in subsurface layers during the day. Ontogenetic changes in vertical distribution were not observed. Residual currents reported in the area (3–6 km·day−1) and duration of larval life (approximately 15–70 days) suggests a minimum potential transport on a 100-km scale. Biological information reported in this work could be explicitly incorporated in a circulation model to accurately predict larval transport and connectivity. Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Lovrich, Gustavo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Rojas, Laura. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Milano, Viviana. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Delourdes Figueroa, Nerina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Baron, Pedro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Universidad Nacional de la Patagonia; Argentina

The coastal hydrodynamics of an eastward-facing bay (Nueva Bay) located in the west coast of Nuevo Gulf (42.76° S, 65.03° W) was inferred using time series of seawater temperature, winds and tides. Temperature was measured at surface and near the bottom at a station with a maximum depth of 18 m. Concurrent observations of wind intensity and direction were registered at ~ 3 km from the station. Tidal levels were predicted using the WXTide software. Surface heat flux explained the observed annual cycle of seawater temperature and the seasonal thermal stratification. Events of upwelling/downwelling were observed associated to offshore/onshore winds, with lags of approximately 5–6 hours. Spectral analysis of the temperature time series showed significant diurnal and semidiurnal peaks during the warm season (spring and summer), when the water column was stratified. The semidiurnal peaks of spectral energy were correlated with the main components of the tidal cycle. Diurnal thermal variability was driven by diurnal cycles of wind (sea breeze) occurring during 52% of spring days and 61% of summer days. We present two conceptual models of nearshore dynamics that are coherent with the observed thermal variability (up to 4 °C in 6 hours).

In this study, fecundity of Munida gregaria in northern Patagonia was analysed in relation to size and compared with other studies in different sites along its latitudinal distribution. Also, morphological changes in embryos reared in the laboratory, and the chronology of its appearance were observed. Fecundity (total number of eggs in a clutch) was strongly correlated to size (carapace length in mm) (R = 0.638) and the regression equation fitted by least squares was Log(F) = −1.37 + 3.85 · log(CL). Size specific fecundity was higher than in southern locations along Patagonia. Recently extruded eggs are smaller than in southern Patagonia measuring an average of 530 μm in diameter and 0.043 mm3 in volume. When ready to hatch, those measures increased by 30% and 50% respectively. Complete embryonic development lasted an average of 27.9 days at fixed temperature of 11°C. Five development stages were defined based on morphological changes: (1) from fertilization to the appearance of embryonic primordium (2–3.5 days); (2) embryonic tissues occupying less than half of the egg perimeter in lateral view (7–10 days); (3) embryonic tissues without pigments and occupying more than half of the egg perimeter in lateral view (5–8 days); (4) embryos with reddish eye pigments and chromatophores (4–6 days); and (5) ocular globe completely pigmented (3–4 days).

Munida gregaria is a small galatheid widely distributed around the southern hemisphere, considered a key species in food webs of coastal and shelf marine ecosystems. Previous studies conducted at 55°S and 46°S on the Atlantic coast of South America, have shown that the species can adapt its reproductive patterns to different environmental conditions. The objectives of this work are to complete this analysis by determining: (1) the reproductive season span; (2) the potential of the species to produce multiple clutches of eggs; (3) the length of its embryonic development; and (4) based on previous objectives, the potential number of clutches produced by M. gregaria by reproductive season in the northern range of its coastal distribution (42-43°S, northern Patagonia). In this region, brooding females were present from June to December, representing more than 80% of total females between July and October. Females presented previtellogenic oocytes beginning maturation just after egg extrusion, and fully developed vitellogenic oocytes just before hatching. From November to February increasing proportions of females showed signs of athresia and resorption of mature oocytes. The complete embryonic development of M. gregaria lasted 26-29 days at 11°C constant temperature. Considering the pattern of synchronous ovary re-maturation and embryonic development, the length of embryogenesis at water temperatures typical from costal waters off northern Patagonia during the breeding season, it is concluded that female M. gregaria have the potential to consecutively lay more than three egg clutches per reproductive season. Copyright © Marine Biological Association of the United Kingdom 2008. Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Baron, Pedro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina

Seaweed (fresh, dry) or its products (extracts, composts, soil conditioners) have been long used in agriculture to enhance plant growth and productivity. In this study, we evaluated the effects that seaweed composts at different doses and degree of maturation had on the yield of tomatoes (Licopersicon esculentum Mill. cv. platense) grown on a horticultural soil in northeastern Patagonia. We used 10 tomato plants per treatmentplot set in a randomized block design. Treatments were: 1) soil without amendment, control (S); 2) 5 kg m−2 of compost aged 9 months (C9-5); 3) 10 kg m−2 of compost aged 9 months (C9-10); 4) 5 kg m−2 of compost aged 20 months (C20-5); and 5) 10 kg m−2 of compost aged 20 months (C20-10). Total weight and number of tomatoes, and aerial plant biomass (excluding fruits) were significantly higher for the compost treatments than those of the control. Also, compost treated plants bore mature fruits, in average, 9 days earlier and presented higher resistance to diseases than controls. The weight of tomatoes per plant grown in C20 was significantly higher than that of C9, differences that could be attributed to the lower salinity of compost C20 (C20 and C9 electrical conductivities were 1.5 and 15 dS m−1, respectively). The increased yield and resistance to diseases on tomato plants by addition of seaweed compost appear to be related to a complex number of factors not yet fully understood. It seems, however, that a combination of higher nutrient availability (mainly P) due to slight increases in pH of the soil amended, together with increases in readily available K and an improvement in soil physical conditions (increase in pore size and probably amelioration of hydric conditions), may have been responsible for the higher production of seaweed amended plots as compared to the control. Fil: Eyras, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Dellatorre, Fernando Gaspar. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina Fil: Defossé, Guillermo Emilio. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina

The feeding behavior of Mytilus edulis platensis, one of the most important aquaculture resources on the East Coast of southern South America, was studied by analyzing clearance rate (CR) and ingestion rate (IR) to test the hypothesis that cultivated mussels can attain higher clearance and ingestion rates than their wild counterparts. A number of morphometric relationships between cultivated and wild mussels were also compared. Gill surface (GS) growth relative to length (L) is isometric in M. e. platensis, with no significant differences between wild and cultivated mussels. At low food concentrations (

The embryonic development of the spider crabs Leurocyclus tuberculosus and Libinia spinosa was divided into five periods based on the differentiation of: (I) cleavage, (II) embryonic primordium, III) optic lobes, (IV) optic lobes pigmented and (V) chromatophores presence. Different traits such as spines, setae and telson morphology distinguish the two species from period III until hatching. Egg volume was greater in Leurocyclus tuberculosus than in Libinia spinosa. The duration of each period was different during development. Whereas in Leurocyclus tuberculosus period II (morphogenesis) is the longest, in Libinia spinosa the period IV is the longest. Complete embryonic development at 14'C lasted 36.7 +/- 3.1 days in Leurocyclus tuberculosus and 57.4 +/- 4.4 days in Libinia spinosa.

Coastal Patagonia, often regarded as a pristine confine of the world ocean, has been invaded by non-indigenous species that are rapidly modifying local ecosystems. One of the most conspicuous invaders is the kelp Undaria pinnatifida. First recorded near the city of Puerto Madryn (Argentina, 42.75°S) in 1992, during the last 15 years its range spread more than five degrees of latitude to the south. By 2007 it was first detected north of Valdes Península (a natural barrier), beginning its northward expansion, and between 2007 and 2011 spread along the coasts of San José and San Matías gulfs at an average rate of ~50 km yr-1. A small population was detected in Mar del Plata (Argentina, 38.04°S) in 2011, more than three degrees of latitude to the north, suggesting a new human-mediated inoculation. Based on experimental information and remotely sensed sea-surface temperature (SST) at the latitudinal range limits of U. pinnatifida populations worldwide, we hypothesize a thermal tolerance window between -0.6 °C and 16.8 °C average SST in the coldest month, and between 20 °C and 28 °C in the warmest month. Using climatologic satellite SST from several locations, we predict a potential latitudinal thermal range extending between Puerto Deseado (Argentina, 47.75°S) and Torres (Brazil; 29.35°S). Salinity and substrate quality however constrain suitable habitat in the southwestern Atlantic to discrete stretches of coastline, suggesting that the northern potential boundary would be around La Coronilla (33.90°S), on the Uruguayan littoral. Fil: Dellatorre, Fernando Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Amoroso, Ricardo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. University of Washington; Estados Unidos Fil: Saravia, José. Provincia del Chubut. Ministerio de Desarrollo Territorial y Sectores Productivos; Argentina Fil: Orensanz, Jose Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina

The embryogenesis of Ovalipes trimaculatus, a member of the highly valued portunid swimming crabs, was studied under nearly constant temperature (13±1°C), salinity (33) and photoperiod (14 h light:10 h dark) conditions. A five-stage scale of embryonic development was defined for the species. Time required to complete development averaged 35.7±2.11 days, showing no significant differences between embryos located in inner, middle and outer portions of the egg mass. The egg chorion was rounded and showed the highest growth in diameter between stages I (morula-blastula-gastrula) and II (primordium of larval structure) and between stages III (appendage formation) and IV (eye formation). Results reported here provide a baseline for optimizing hatchery operations and useful information for management purposes.

The embryonic development of the spider crabs Leurocyclus tuberculosus and Libinia spinosa was divided into five periods based on the differentiation of: (I) cleavage, (II) embryonic primordium, III) optic lobes, (IV) optic lobes pigmented and (V) chromatophores presence. Different traits such as spines, setae and telson morphology distinguish the two species from period III until hatching. Egg volume was greater in Leurocyclus tuberculosus than in Libinia spinosa. The duration of each period was different during development. Whereas in Leurocyclus tuberculosus period II (morphogenesis) is the longest, in Libinia spinosa the period IV is the longest. Complete embryonic development at 14'C lasted 36.7 +/- 3.1 days in Leurocyclus tuberculosus and 57.4 +/- 4.4 days in Libinia spinosa.