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The state of Espírito Santo has one of the greatest diversities of macroalgae along the Brazilian coast. Beach-cast seaweeds are a frequent phenomenon and exhibit great diversity. This study assessed stranded macroalgae's composition and reproductive status to evaluate their potential for sustainable use by the local community. Monthly collections were carried out from March to November 2022, covering the rainy and dry seasons, on five beaches in Espírito Santo: three in the north and two in the south. At each beach, two 50 m transects were set up parallel to the coastline over the stranded algae patches, one near the wave-breaking zone during low tide and another around high tide, and three 1 × 1 m quadrants were randomly selected in each transect. All material within each quadrant was collected, resulting in six samples per beach. We identified 81 taxa, including 54 Rhodophyta, 16 Ulvophyceae and 11 Phaeophyceae. The taxon composition was relatively consistent across the studied regions, with the rainy season exhibiting the greatest species richness. Seventeen of the identified taxa had reproductive structures, although only four consistently presented these structures. Our results suggest that removing stranded macroalgae does not significantly impact their role as propagule sources. [ABSTRACT FROM AUTHOR]

Macroalgae are a natural oceanic resource of inexhaustible abundance for the biomass energy industry with growth rates that are three to four times greater than those of terrestrial plants. The objective of this study was to evaluate the sustainability of macroalgae as biomass for biorefining through two investigations. Firstly, the deposition of macroalgae was sampled through 28 collections on seven beaches in the city of Maceió, Brazil, over a two-year period using a zigzag sampling method, covering a deposition area of 135,000 m2. From this, it was estimated that daily collection would yield 5.03 t/ha of dry biomass. Secondly, the calorific values of macroalgal biomass energy and pellet compounds were calculated. The lower calorific value (8.82 MJ/kg) found from a compound of 13 species analyzed was similar to that of the main biomass used in Brazil to obtain energy, i.e., sugarcane bagasse, which has been evaluated as 8.91 MJ/kg. Macroalgal biomass in the form of condensed energy pellets was found to have a higher calorific value of 20.18 MJ/kg, i.e., 1.2% greater than the average for terrestrial biomass pellets. Based on the results obtained, it was observed that macroalgal biomass has the possibility of becoming a new renewable feedstock with potential for bioenergy. The estimates for the deposition of biomass show possibilities for producing biofuels from marine algal raw material, which provides scope for creating another sustainable alternative for global energy issues with a reduction in environmental problems. [ABSTRACT FROM AUTHOR]

Seaweed extracts have several functions in agriculture due to their composition that is rich in nutrients, plant hormones, and bioactive substances. It is a natural product used as a biostimulant especially to promote the growth and development of plants and their tolerance to environmental stresses. The objective of this study was to analyze the response to a biostimulant containing seaweed extract derived from Ascophyllum nodosum in the cultivation of tomato and eggplant seedlings, analyzing the growth and physiological parameters in two different regions of Brazil. Cherry tomato and eggplant were cultivated in polyethylene trays for 30 days. In each crop, five treatments were tested, comparing the use of a commercial seaweed extract in application doses and forms, which were the control (without seaweed application); 0.1%, 0.2%, and 0.3% of the seaweed extract applied by irrigation water; and treatment with 0.2% of the seaweed extract by foliar application. This study confirms the efficacy of incorporating seaweed extract from Ascophyllum nodosum as a bio-input into the production phase of Solanaceae seedlings. The seedlings which received the seaweed extract significantly increased some morphological parameters, mainly regarding the biomass and length of leaves, stems, and roots. In general, applying both methods through irrigation water and foliar application were effective in providing benefits compared to the control treatment. The intermediate dose (0.2%) was the most effective in promoting improvement in the analyzed parameters. This underscores the importance of obtaining quality seedlings for subsequent planting in the field, potentially leading to better acclimatization and initial adaptation. [ABSTRACT FROM AUTHOR]

There have been beaching events of the marine alga pelagic sargassum in coastal regions of the Caribbean Sea, West African countries, and the north-northeast region of Brazil since 2011. Its presence has caused environmental and socioeconomic impacts while several studies were conducted in order to understand the causes of this phenomenon, as well as alternatives to mitigate its impacts. The objective of this research was to evaluate pelagic sargassum biomass from beaching as a raw material for the manufacture of medium-density multilayer particleboards, aiming for an application that can reduce the impacts generated by the disposal of this seaweed on beaches and landfills. These are composed of 30% sargassum particles in their inner layer and 70% sugarcane bagasse particles on their outer layers, which are bonded with castor-oil-based polyurethane resin. A physical and chemical characterization was carried out in order to evaluate sargassum particles while physical and mechanical tests were carried out in order to evaluate the panels. Results were subsequently compared with indications from different particleboard standards. A life cycle assessment was carried out to complement the feasibility study of these panels and to compare their different manufacturing processes. The multilayer panels met the minimum requirements for physical and mechanical properties established by regulations, indicating that the Sargassum spp. biomass can be used as filling. The life cycle assessment study indicates that sargassum panels produced in the Belém, PA, Brazil, region present lower environmental impacts in four of seven evaluated categories when compared to conventional panels. Given the results obtained, the use of sargassum from beaching events as raw material for panels can be presented as an alternative for reducing social, economic, and environmental impacts in the regions affected by these events. [ABSTRACT FROM AUTHOR]

The present study aimed to analyze the application of a seaweed biofertilizer as an attenuator of salt stress on the morphophysiology of scarlet eggplants. The experiment was carried out under protected conditions in Areia, PB, Brazil, using an incomplete factorial arrangement in a randomized block design with four replications and two plants per plot by adopting the Box Central Composite Design with five electrical conductivities of irrigation water – ECiw (0.50 – control, 1.15, 2.75, 4.35 and 5.00 dS m−1) and five concentrations of seaweed biofertilizer (0 – control, 1.45, 5.00, 8.55 and 10 mL L−1). The electrical conductivity of irrigation water at values starting at 0.5 dS m−1 negatively affected the growth of scarlet eggplants. Therefore, the crop is considered sensitive to salt accumulation. The increase in electrical conductivity of irrigation water negatively affected the morphophysiology of scarlet eggplants, with reductions higher than 10% at electrical conductivity values higher than 1.37 dS m−1. Biofertilization at 6.67 mL L−1 mitigates the effects of salt stress on the gas exchange variables and the phytomass accumulation of scarlet eggplants 60 days after sowing. The seaweed biofertilizer can be used to improve the physiological and morphological performance of scarlet eggplants. [ABSTRACT FROM AUTHOR]

The green algal genus Ulva is one of the most widely distributed macroalgal genera. The taxonomy of Ulva is problematic due to its simple morphology. The study of the diversity of this genus has undergone great advances using molecular data, leading to changes in the taxonomic status of species, and the recognition of species complexes and cryptic species. Here we reassessed Ulva species from southeastern Brazil using molecular data. We recognized 10 taxa, among which only three previously reported species were confirmed by molecular data: U. compressa, U. lactuca and U. ohnoi, the latter recently recorded from insular waters in Fernando de Noronha Archipelago, northeastern Brazil. Our phylogenetic analyses and species delimitation methods strongly supported the establishment of Ulva kanagawae sp. nov. The species traditionally cited for southeastern Brazil, U. flexuosa, U. linza, U. rigida and U. paradoxa, proved to be misapplied names of U. tepida, U. aragoënsis, U. ohnoi/U. lactuca and U. torta, respectively. One taxon, Ulva sp., remains unnamed and needs further studies. Ulva chaugulei and U. tanneri, both considered here as cryptogenic species, are new occurrences for Brazil expanding their geographic distribution to the Atlantic Ocean and western Atlantic Ocean, respectively. In addition, our analysis of sequences from type materials revealed that U. pseudo-ohnoi is a heterotypic synonym of U. conglobata. This first systematic molecular study of Ulva species in Brazil points out that more extensive sampling is needed to reveal the true diversity of the genus in Brazilian waters. [ABSTRACT FROM AUTHOR]

Colpomenia sinuosa is a cosmopolitan brown macroalgal species complex and hence a great candidate for evolutionary studies in the marine environment. Since 2009, three major C. sinuosa phylogenetic lineages, subdivided into eight subgroups, have been identified based on cox3 DNA sequences from worldwide collections. However, worldwide sampling remains limited and spotty. To date molecular data from Brazilian C. sinuosa populations have been limited to 10 specimens collected in a single locality. Nonetheless, C. sinuosa populations occur along the entire ~8,000 km Brazilian coast. Consequently, knowledge on population genetic diversity and spatial genetic structuring along most of the Brazilian coastline is nonexistent. To fulfill this gap in knowledge, we performed a phylogeographic analysis of C. sinuosa populations in Brazil. The highly variable cox3 marker was sequenced for 148 individuals collected in 12 localities in Brazil. Results identified two genetically distinct population groups (north vs. south) separated at 20.5° S latitude. Genetic diversity in northern populations is 14.6 and 15.5 times greater than southern populations in terms of haplotype and nucleotide diversity, respectively. Among northern populations, the Bahia state holds the largest genetic diversity. The southern populations had lower genetic diversity and no internal genetic sub‐structure suggesting past bottlenecks followed by recent colonization from northern haplotypes. Our results do not indicate recent introductions of foreign haplotypes in Brazil and reinforce the crucial importance of historical and extant allopatric, parapatric, and sympatric processes driving marine macroalgal evolution in the Southwestern Atlantic Ocean. [ABSTRACT FROM AUTHOR]

The present review aims the discussion of the impact of the bioprospection initiative developed by the projects associated to BIOprospecTA, a subprogram of the program BIOTA, supported by FAPESP. This review brings a summary of the main results produced by the projects investigating natural products (NPs) from non-plants organisms, as examples of the success of this initiative, focusing on the progresses achieved by the projects related to NPs from macroalgae, marine invertebrates, arthropods and associated microorganisms. Macroalgae are one of the most studied groups in Brazil with the isolation of many bioactive compounds including lipids, carotenoids, phycocolloids, lectins, mycosporine-like amino acids and halogenated compounds. Marine invertebrates and associated microorganisms have been more systematically studied in the last thirty years, revealing unique compounds, with potent biological activities. The venoms of Hymenopteran insects were also extensively studied, resulting in the identification of hundreds of peptides, which were used to create a chemical library that contributed for the identification of leader models for the development of antifungal, antiparasitic, and anticancer compounds. The built knowledge of Hymenopteran venoms permitted the development of an equine hyperimmune serum anti honeybee venom. Amongst the microorganisms associated with insects the bioprospecting strategy was to understand the molecular basis of intra- and interspecies interactions (Chemical Ecology), translating this knowledge to possible biotechnological applications. The results discussed here reinforce the importance of BIOprospecTA program on the development of research with highly innovative potential in Brazil. [ABSTRACT FROM AUTHOR]

Drought is one of the most important abiotic stresses responsible for reduced crop yields. Drought stress induces morphological and physiological changes in plants and severely impacts plant metabolism due to cellular oxidative stress, even in C4 crops, such as sugarcane. Seaweed extract-based biostimulants can mitigate negative plant responses caused by drought stress. However, the effects of foliar application of such biostimulants on sugarcane exposed to drought stress, particularly on plant metabolism, stalk and sugar yields, juice purity, and sugarcane technological quality, have received little attention. Accordingly, this study aimed to evaluate the effects of foliar application of a seaweed extract-based biostimulant on late-harvest sugarcane during the driest period of the year. Three experiments were implemented in commercial sugarcane fields in Brazil in the 2018 (site 1), 2019 (site 2), and 2020 (site 3) harvest seasons. The treatments consisted of the application and no application of seaweed extract (SWE) as a foliar biostimulant in June (sites 2 and 3) or July (site 1). The treatments were applied to the fourth ratoon of sugarcane variety RB855536 at site 1 and the fifth and third ratoons of sugarcane variety SP803290 at sites 2 and 3, respectively. SWE was applied at a dose of 500 ml a.i. ha−1 in a water volume of 100 L ha−1. SWE mitigated the negative effects of drought stress and increased stalk yield per hectare by up to 3.08 Mg ha−1. In addition, SWE increased stalk sucrose accumulation, resulting in an increase in sugar yield of 3.4 kg Mg−1 per hectare and higher industrial quality of the raw material. In SWE-treated plants, Trolox-equivalent antioxidant capacity and antioxidant enzyme activity increased, while malondialdehyde (MDA) levels decreased. Leaf analysis showed that SWE application efficiently improved metabolic activity, as evidenced by a decrease in carbohydrate reserve levels in leaves and an increase in total sugars. By positively stabilizing the plant's cellular redox balance, SWE increased biomass production, resulting in an increase in energy generation. Thus, foliar SWE application can alleviate drought stress while enhancing sugarcane development, stalk yield, sugar production, and plant physiological and enzymatic processes. [ABSTRACT FROM AUTHOR]

Rhodolith beds are biogenic benthic habitats mainly formed by unattached, non-geniculate coralline algae, which can be inhabited by many associated species. The Brazilian continental shelf encompasses the largest continuous rhodolith bed in the world. This study was based on samples obtained from seven sites and videos taken by a Remotely Operated Vehicle (ROV) at four transects off the Sergipe-Alagoas Coast on the northeast Brazilian shelf. ROV operations and bottom trawl sampling revealed the occurrence of rhodolith beds between 25 and 54 m depths. At the shallower depths, fruticose (branching) rhodoliths (maërl) appear in troughs of ripples, and other non-branching rhodoliths occur associated with corals and sponge patches surrounded by bioclastic sand. Rhodoliths also occur in patches from 30 to 39 m depth; some are fused, forming larger, complex tridimensional structures. At deeper depths, from 40 to 54 m, the abundance of rhodoliths increases and occur associated with fleshy macroalgae on a smooth seafloor; some rhodoliths are fused into complex structures, locally some are fruticose (maërl), and others are partially buried by fine-grained sediment. The collected rhodoliths vary from fruticose in two sites to encrusting to lumpy, concentric and boxwork nodules in the rest; their size ranges from small (<1.5 cm) to large (~6 cm) and are mostly sub-spheroidal to spheroidal. A total of 16 red algal morpho-taxa were identified in the study sites. Two phases of growth can be distinguished in some rhodoliths by changes in color. The brownish inner cores yielded ages of 1600–1850 cal years before the present, whereas outer layers were much younger (180–50 years BP old). Growth layers appeared to have been separated by a long period of burial in the seafloor sediment. Other rhodoliths have ages of hundreds of years. [ABSTRACT FROM AUTHOR]

The amount of sargassum seaweed washed ashore on the beaches of Africa, Brazil, Central America and the Caribbean has increased to the point where it has become a social, environmental and financial issue. This research evaluates the potential for Sargassum spp. of the Mexican Caribbean coast to be used in the production of biomethane by estimating: a) stoichiometric methane production (SMP), b) biochemical methane potential (BMP) and c) biodegradability index (BI). The use of a sigmoidal model generalized to substrate to inoculum ratios is proposed, to predict the biomethane production during the anaerobic digestion (AD) of the sargassum. The information obtained shows the seaweed's potential for biomethane production and will be useful for estimates and scaling when implementing energy harnessing systems for sargassum in the Caribbean. The use of biomass is a key element in the move towards a circular economy. It is hoped that the use of technologies like AD leads to the integration of this seaweed into an economic value chain, thereby reducing the adverse effects of its presence on the ecosystem. [ABSTRACT FROM AUTHOR]

Rhodoliths are free-living and morphologically diverse marine calcareous algae commonly distributed over the continental shelf seafloor. They increase the seabed structural complexity and are of potential value as feeding and reproductive grounds for a myriad of marine fauna. The higher structural seabed complexity within rhodolith beds may also increase benthic diversity by creating microhabitats, but this relationship has been rarely explored within rhodolith beds worldwide. Here we compared benthic macrofaunal (>500 µm) structure on rhodolith beds (nodule epifauna) and within unconsolidated sediments (sediment infauna) under high and low-density beds to test whether rhodolith bed density and nodule morphology influenced macrofaunal assemblages. We observed that macrofaunal density on nodules (2538 ± 288.7 ind·m−2 ) was 15-fold higher when compared to sediments under those beds (166 ± 38.8 ind·m−2 ). Rhodolith bed density was positively related to macrofaunal density, composition, and functional diversity on the rhodoliths. Low-density beds (61 ± 27.1 nodules·m−2 ) with discoid-shape nodules were dominated by peracarid crustaceans whereas high-density beds (204 ± 18.7 nodules·m−2 ) with spheroidal nodules were dominated by Annelid polychaetes. The sediment macrofauna was also positively influenced by the density of rhodolith nodules, which increased sediment carbonate and organic quality (protein and lipids) under high-density beds. Macrofaunal functional diversity was generally higher on rhodoliths, with low similarity (low nestedness) and high taxa turnover between macrofaunal assemblages of rhodoliths and sediments. These findings indicate that rhodolith beds provide an unique habitat for benthic macrofaunal communities, with exclusive functional and taxonomic richness that are likely not typical in the unconsolidated sediment below these beds in SE Brazil. This study highlights the importance of protecting rhodolith beds from multiple sources of anthropogenic disturbance and exploration on continental shelves. [ABSTRACT FROM AUTHOR]

Macroalgae constitute an important habitat for several marine invertebrates, and their biomass and structural complexity modulates the abundance and diversity of species that live on them. Overall, fluctuations in algae biomass inflict fluctuations in the abundance of the associated mobile macrofauna, but the structure of the community may vary according to how each group/species uses the resources provided by the algal habitat. Here, we evaluated how temporal variations in the biomass of Sargassum algal bed (increase, decrease, or maintenance) can affect the abundance, density, and assemblage structure of distinct associated faunistic groups. The collections were performed in three rocky shores located on the north coast of São Paulo, southeastern Brazil, during Fall and Spring. We observed different patterns of algal substrate variation between sampling events, and this reflected on variable effects on the associated fauna. The algal substrate reduction was accompanied by the reduction in the abundance and density of all associated faunal groups. However, the increase or maintenance of the algal substrate was accompanied by an increase in the abundance of peracarids, due to the dominance of herbivorous species, while other taxonomic groups like mollusks and polychaetes decreased or maintained their abundance, although with higher species evenness of gastropods when alga increases. Seasonal biomass variations in macroalgae beds are relevant for the dynamics of its associated fauna, and our results indicate that some taxonomic groups may preferentially use the available extra resources originated from biomass increment when compared to other groups. [ABSTRACT FROM AUTHOR]

The contents of 24 elements were determined in seven species of macroalgae collected in Ceara-Brazil, in the rainy and dry seasons of 2022. The samples were digested, and the analytes were quantified by ICP-OES and Hg by direct analyzer. The CRM CD-200 was analyzed for accuracy and obtained recoveries were higher than 95 %. The seaweed species have different inorganic element profiles with predominant elements being: Ca, K, Na, Mg and P. The Sargassum vulgare species stood out for its Hg and As contents (1.479 ± 0.005 mg kg−1 and 172 ± 6 mg kg−1, both in the rainy seasons). Ulva lactuca attracted attention for its high concentration of V (46.4 ± 3.4 mg kg−1, rainy season). In general, the elemental content levels in the macroalgae samples were higher in the rainy season. Long-term studies to comprehend the effect of seasonality on the elemental composition of seaweed must be carried out. [Display omitted] • Elemental content of 7 seaweed species from Northeast of Brazil was firstly described. • Seasonality had an influence on the elemental content level of all seaweed samples. • High concentrations of As and Hg were found in a brown species of seaweed. [ABSTRACT FROM AUTHOR]

Souza Pereira de Ávila, A.; Leonhardt, A., and Diniz, D., 2020. Paleoenvironmental reconstruction off southern Brazil during a glacial period (66.5–47 kyr BP): Continental and oceanic environments. Journal of Coastal Research, 36(6), 1204–1214. Coconut Creek (Florida), ISSN 0749-0208. Based on the palynological record of core REG 972, this work aimed to reconstruct the paleoclimatic and paleoenvironmental history from 66.5 to 47 kyr BP at the south Brazilian continental margin, as well as to identify the influence of continental discharge in the southern portion of the Rio Grande Cone. Nineteen samples were processed following the standard methodology for palynological studies. Organic matter (OM) content was measured in the sediments. The age model was established according to 18O isotopes analyses in benthic foraminiferal tests. The studied interval corresponds to a glacial interval, divided in palynozones (PZs): PZIa (66.5–64.5 kyr), PZIb (64.5–53.5 kyr), and PZII (53.5–47 kyr). PZIa was characterized by drier conditions, with grassland and salt marsh taxa dominance (Cyperaceae and Amaranthaceae). During PZIb and PZII, the increase of Bryophyta, Pteridophyta, Araucaria angustifolia, Arecaceae, and Alchornea triplinervia points to wetter and warmer conditions that may be related to the beginning of marine isotope stage 3 and later to the sea-level rise. In the oceanic environment, the presence of freshwater algae and marine indicators lead to the conclusion that marine conditions prevailed during Rio Grande Cone sedimentary formation, even under low sea-level conditions when terrigenous influence was stronger. The data on OM content, dinoflagellate taxa, and mean sea level changes point to a period of low productivity during PZI. In PZII, a period of higher productivity took place because of Subantarctic Shelf Water influence, bringing cold and nutrient-rich waters to the area. [ABSTRACT FROM AUTHOR]

Simulations were performed to evaluate the economic potential of farming the seaweed Hypnea pseudomusciformis in two production scales for the carrageenan, human food, and glycolic extract markets in Brazil. The initial investment was low in all scenarios (US$25,579 in 7.5 ha and US$71,202 in 22.5 ha farms). Labor and taxes were the major production costs for production commercialized for the carrageenan and human food markets, respectively. Liquid glycerin and bottles were the main costs when the productions were marketed for glycolic extract. The carrageenan market showed no economic feasibility. On the other hand, the human consumption market was shown as very profitable, resilient, and highly attractive (IRR was ∼100%). Marketing the glycolic extract is also feasible and attractive (IRR was ∼25%) but had lower economic indicators and low resilience when compared to the human food market scenario. Upscaling the production optimized investments and reduced production costs, improving profitability. The plasticity of seaweed enables entrepreneurs to explore different markets simultaneously to increase farm resilience. [ABSTRACT FROM AUTHOR]

Chikungunya virus (CHIKV) infection is one of the most challenging re-emergent diseases caused by a virus, and with no specific antiviral treatment it has now become a major public health concern. In this investigation, 25 blood samples were collected from patients with characteristic CHIKV symptoms and submitted to a virus isolation protocol, which detected 3 CHIKV isolates. These samples were evaluated by sequencing for the characterization of the strains and any homology to viruses circulating in Brazil during a recent outbreak. These viruses were used for the development of antiviral assays. Subsequently, the inhibitory effects of seaweed extracts on CHIKV replication were studied. The marine species of algae tested were Bryothamnion triquetrum, Caulerpa racemosa, Laurencia dendroidea, Osmundaria obtusiloba , Ulva fasciata , and Kappaphycus alvarezii , all of which are found in different countries including Brazil. The results revealed high levels of CHIKV inhibition, including extracts of O. obtusiloba with inhibition values of 1.25 μg/mL and a selectivity index of 420. Viral inhibition was dependent on the time of addition of extract of O. obtusiloba to the infected cells, with the optimal inhibition occurring up to 16 h after infection. Neuron evaluations with O. obtusiloba were performed and demonstrated low toxicity, and in infected neurons we observed high inhibitory activity in a dose-dependent manner. These results indicate that the algal extracts may be promising novel candidates for the development of therapeutic agents against CHIKV infections. [ABSTRACT FROM AUTHOR]

In 1998 Critchley and Ohno published the book Seaweed resources of the world presenting a synthesis of knowledge on the subject from different regions and countries globally. One chapter by E.C. Oliveira was focused on Brazil. In this article, we present an update of the economically relevant species of Brazilian seaweeds, and their distribution along the coastline, and what has changed over 20 years in the status of the exploited resources, the new species with commercial potential, and relevant legislation. The only introduced commercial species, Kappaphycus alvarezii, was economically exploited for a while in Rio de Janeiro State, but nowadays there are no commercial activities on a large scale. Gracilaria farms in the northeast are still on an artisanal scale, but the expansion of activity is compromised by legal and bureaucratic barriers. Regulations related to the exploitation of natural beds and to the introduction of new strains of K. alvarezii were created between 2006 and 2008. At the end of this article, we present a reflection of what lessons have been learned and what are the prospects for seaweed cultivation in Brazil. [ABSTRACT FROM AUTHOR]

The exploration of seaweed diversity in poorly studied habitats has often led to the discovery of new species. Sandcovered rocks are an example, as they received less attention than sand-free rocky intertidal habitats during seaweed diversity surveys in Brazil. In sand-covered rocks from Espírito Santo and Rio de Janeiro we found an alga whose morphology was unique among rhodomelacean species previously reported in Brazil. With the aim to clarify the taxonomic identity of this species we studied its morphology, as well as its phylogenetic relationships. Molecular analyses resolved this species in the genus Alsidium (tribe Alsidieae) and differed from sequenced congeners with divergences ≥2.5 and 4.2% in the rbcL and cox1 genes, respectively. Morphological characters were in agreement with the genus Alsidium, and differed from other species currently recognized in the genus. The species consisted of a basal crust and scarcely branched erect axes with seven pericentral cells covered by a continuous layer of cortical cells. Reproductive structures were formed on clusters of short determinate branches. Therefore, the new species A. oliveiranum is proposed based on morphological and molecular evidence. Our findings contribute to better understand the diversity of the tribe Alsidieae, which is particularly diverse in the Americas. [ABSTRACT FROM AUTHOR]

Since 2011, tropical beaches from Africa to Brazil, Central America, and the Caribbean have been inundated by tons of sargassum seaweed from a new equatorial source of pelagic sargassum in the Atlantic. In recent years the extraordinary accumulations of sargassum make this a nuisance algal bloom for tropical coasts. In 2018 satellite data indicated floating mats of sargassum that extended throughout the Caribbean to the northeast coast of Brazil with the highest percent coverage over the water yet recorded. A literature review suggests that Atlantic equatorial recirculation of seaweed mats combined with nutrients from several possible sources may be stimulating the growth and accumulations of sargassum. In the western equatorial recirculation area, new nutrient sources may include Amazon River floods and hurricanes; in the eastern equatorial recirculation area, nutrient sources that could sustain the sargassum blooms include coastal upwelling and Congo River freshwater and nutrients. • Tons of sargassum seaweed on Caribbean beaches • The Atlantic Equatorial Recirculation Area a new source of sargassum seaweed • Nutrients to support sargassum come from the Amazon River floods and hurricanes. • Nutrients to sustain sargassum originate in the Eastern Atlantic Equatorial. [ABSTRACT FROM AUTHOR]

• We found a latitudinal gradient in intertidal seaweed species turnover and richness along southern Brazil and Uruguayan coast. • Sea surface temperature and salinity are the main drivers of the seaweed species distribution, despite changes in coastal geomorphology. • The lowest seaweed species richness is observed across the latitude of 32 °S and 37 °S, a transitional warm-temperate region. • The study fulfills knowledge gaps in the Southwestern Atlantic Ocean seaweed biogeography. • By integrating historic and recent data, the results provide baselines for conservation and detection of future changes. Seaweed latitudinal patterns of diversity present singularities, with implications for ecological, biogeographic and conservation studies. Despite observed global trends, distinct gradients of marine biodiversity occur along the Southwestern Atlantic (SWA) coast. However, the transitional warm-temperate marine province is a major knowledge gap, limiting conclusions about regional seaweed biodiversity. Our study investigated the composition of macroalgal assemblages in rocky intertidal shores between southern Brazil and Uruguay (from 26 °S to 35 °S), accounting for the regional oceanography and coastline features. Integrating historical and new data, we found a significant latitudinal gradient in seaweed species richness and turnover. The complex thermo-haline structure of the coastal waters, summed to large local fluvial discharges (i.e., La Plata River and Patos-Mirim Lagoon), significantly impacted the distributional pattern of macroalgal assemblages. Sea surface temperature and salinity are the main drivers of the species composition and distribution, despite the changes in coastal geomorphology and substrate availability. Whilst the northernmost section (26 °S–29 °S) was characterized by a tropical/warm-temperate phycoflora, the southernmost (32 °S–35 °S) was dominated by eurythermic and euryhaline species. Taking into account this and previous phycogeographic studies, the lowest seaweed species richness seen in SWA rocky shores occurs across 32 °S and 37 °S, while increasing towards both north (into the tropical marine province) and south (into the cold-temperate marine province). Our study fulfills knowledge gaps in Southwestern Atlantic Ocean biogeography, providing baseline information for conservation efforts and for the detection of ongoing human impacts on intertidal macroalgal assemblages. [ABSTRACT FROM AUTHOR]

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Macroalgal bloom events have been frequent in recent years. Eutrophication and overexploitation fishing may favor blooms through nutrient availability and capturing top predators. We aim to investigate the drivers of the macroalgae blooms and their consequences on the food web of the two tropical coastal ecosystems: Porto do Mangue (with high macroalgae production) and Baía Formosa (control environment, without macroalgae), both exploited by artisanal fisheries in northeastern Brazil. The food webs are modeled using the Ecopath with Ecosim (EwE) approach. Our results suggest that fishing did not favor macroalgae blooms but rather the high concentration of nutrients added to the semi-arid conditions. Furthermore, the macroalgae bloom showed low trophic impact, so much of their biomass is transferred into detritus. However, when it decomposes, this accumulation of matter alters the structure and functioning of the ecosystem, affecting its main fish resources: shrimp and piscivorous fish. Investigating blooms is key to management. • Macroalgae bloom can affect coastal food web and fishery production. • We compare two tropical marine food webs, with and without macroalgae production. • A high nutrient load causes the macroalgae bloom. • The macroalgae bloom are little consumed by the fauna, being deposited in the sediment as detritus. • Macroalgae bloom have reduced biomass of shrimp, piscivorous fish, and trophic complexity. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Epiphytic diatoms associated with three species of seaweeds, the phaeophyte Bachelotia antillarum, the ulvophyte Caulerpa verticillata, and the rhodophyte Haloplegma duperreyi, were investigated in the subtidal zone of Northeastern Brazil. A total of 54 diatom species were recorded, distributed among motile (24 species), erect (20 species), and adnate growth forms (five species), in addition to accidental occurrences (five species). Although motile diatoms showed the highest number of species, erect growth forms were the most abundant, accounting for 69% of the entire epiphytic diatom cell abundance. The total abundance ranged from 29,783 to 45,842 cells g-1 wet weight (ww), with Melosira moniliformis (erect), Rhabdonema adriaticum (erect), Cocconeis scutellum (adnate), and Surirella fastuosa (motile) as the most abundant species. The results confirmed qualitative and quantitative differences between the hosts with a greater shape diversity in B. antillarum whose thalli (filamentous-like tufts) offered an increased surface area for colonization mainly by epiphytic erect growth forms. [ABSTRACT FROM AUTHOR]

Assemblages of cryptospores were reported and detailed for the first time from the Upper Ordovician from Brazil. These assemblages were recovered from diamictites and shales with dropstones of the Iapó Formation, Rio Ivaí Group, Paraná Basin. The analyzed sequence represents the Hirnantian glacial deposits containing well-preserved palynomorphs with low thermal maturity and low total organic carbon. The cryptospore assemblages comprise monads, dyads, permanent tetrads, and polyads, naked or enclosed in an envelope, totalizing 17 species. The associated marine palynomorphs consist of 12 species of acritarchs and prasinophycean algae which are not discussed in detail herein. It is noticied the occurrence of Tortotubus protuberans and abundant black fragments at the lowermost portion of diamictites. The Late Ordovician cosmopolitan assemblages of cryptospores corroborate the early radiation of the land plants in western Gondwana. These results contribute to a better knowledge of Late Ordovician in Brazil and more generally in South America. • Evidence of early land plants from the glacial environment in South America. • Palynomorphs of the Hirnantian, Paraná Basin, Late Ordovician of Brazil. • The cryptospores assemblage comprises the oldest evidence of early land plants in Brazil. [ABSTRACT FROM AUTHOR]

Increasing oceanic CO 2 has caused a decrease in oceanic pH, a process termed ocean acidification (OA). OA may benefit fleshy macroalgae due to the increased availability of inorganic carbon sources for photosynthesis since they are tolerant of decreases in pH. In this study, we analyzed multiple physiological responses of Bostrychia montagnei and Bostrychia calliptera from two biogeographic provinces of Brazil (Tropical Southwestern Atlantic [TSA] and Warm Temperate Southwestern Atlantic [WTSA]) after culturing them at a set of bioreactors in three pH levels (7.2, 7.6, and 8.0). Two pH were decreased by CO 2 enrichment into the culture medium. Molecular analyses using plastidial (rbc L-3P) and mitochondrial (COI-5P) DNA markers were also performed to identify genetic divergences between macroalgae from TSA and WTSA. Molecular evidence of COI-5P marker demonstrated that the specimens of both B. montagnei and B. calliptera from TSA and WTSA constitute different haplotypes, with a strong segregation between them. Macroalgae from both localities increased their growth in treatments of decreased pH with increased CO 2 availability. Overall, physiological responses of the algae were not negatively affected by decreased pH. B. montagnei from TSA increased its polysaccharide and allophycocyanin content at pH 7.2, and B. montagnei from WTSA increased its low molecular weight carbohydrate content at pH 7.2 as well. Antioxidant activity — a proxy for physiological stress — was not affected by decreased pH. Our study indicates that haplotypes of B. montagnei and B. calliptera from TSA and WTSA can be relevant to CO 2 sequestration in mangroves once they are tolerant of decreased pH and increase their growth under increased CO 2 availability. [Display omitted] • Bostrychia species show tolerance to decreased pH by CO 2 enrichment of the seawater. • Bostrychia species increase their growth under increased CO 2 availability. • Bostrychia species can be relevant to CO 2 sequestration in mangroves. • Mitochondrial DNA marker reveals genetic divergence between Bostrychia populations from tropical and subtropical regions. • Overall, Bostrychia physiology is not negatively affected by ocean acidification. [ABSTRACT FROM AUTHOR]

The aim of this work is focused on the extraction and characterization of the Brazilian seaweed Sargassum filipendula alginate. Alginates obtained at different seasons were characterized by liquid state nuclear magnetic resonance spectroscopy and scanning electron microscopy. The alginate extraction efficiency was about 20%. Different seasons of the year and different stages in the life cycle of Sargassum sp. in southeastern Brazil influenced the M/G and, consequently, the technological properties of extracted alginates. [ABSTRACT FROM AUTHOR]

This study investigated the biological activities of five benthic marine algae collected from Northeastern Region of Brazil. The tested activities included larvicidal activity against Aedes aegypti, molluscicidal activity against Biomphalaria glabrata, and toxicity against Artemia salina. Extracts of Ulva lactuca (Chlorophyta), Padinagymnospora, Sargassum vulgare (Phaeophyta), Hypnea musciformis, and Digenea simplex (Rhodophyta) were prepared using different solvents of increasing polarity, including dichloromethane, methanol, ethanol, and water. Of the extracts screened, the dichloromethane extracts of H. musciformis and P. gymnospora exhibited the highest activities and were subjected to bioassay-guided fractionation in hexane and chloroform. The chloroform fractions of the P. gymnospora and H. musciformis extracts showed molluscicidal activity at values below 40 μg-mL-1 (11.1460 μg-mL-1 and 25.8689 μg-mL-1, resp.), and the chloroform and hexane fractions of P. gymnospora showed larvicidal activity at values below 40 μg-mL-1 (29.018 μg-mL-1 and 17.230 μg-mL-1, resp.). The crude extracts were not toxic to A. salina, whereas the chloroform and hexane fractions of P. gymnospora (788.277 μg-mL-1 and 706.990 μg-mL-1) showed moderate toxicity, indicating that the toxic compounds present in these algae are nonpolar. [ABSTRACT FROM AUTHOR]

Abstract: Aedes aegypti is considered to be the main vector of a group of arboviruses responsible for dengue and yellow fever. In an attempt to find natural products that could be employed in the effective control of the dengue mosquito, the larvicidal activities of crude extracts obtained from 15 seaweed species collected from northeastern Brazil have been determined. Extracts of Canistrocarpus cervicornis, Laurencia dendroidea, Hypnea musciformis and Chaetomorpha antennina at concentrations of 300ppm showed ≥50% mortality against fourth instar larvae of A. aegypti. The strongest larvicidal activities (>91% mortality at 50ppm) were obtained with extracts of L. dendroidea. A halogenated sesquiterpene, identified as elatol, was isolated by sequential fractionation of the n-hexane extract of this species of seaweed, and the isolated compound exhibited potent larvicidal activity with an LC50 value of 10.7ppm. The isolation of elatol from seaweed could represent an interesting prospect for a novel agent against the dengue mosquito. [Copyright &y& Elsevier]

The brown seaweed Sargassum vulgare C. Agardh abounds along the southeast coast of Rio de Janeiro State, Brazil, creating unique habitats, and its polyphenols play an important ecological role as antifouling agents. In order to understand more precisely this defensive strategy of S. vulgare, we collected this macroalga at Ilha de Itacuruçá in May and October 2009. Thalli were separated according to tissue type: pneumatocysts, receptacles, leaflets, and axis. Phenolic extracts from each specific part of the plant were obtained and the associated antifouling activity was tested in order to assess whether a tissue specialisation/antifouling activity pattern exists. Preliminary separation process was carried out on a phenolic extract to separate the polyphenols from the remaining compounds. Such fractionation allowed us to study the involvement of strictly phenolic compounds in antifouling activity. Within-thallus variation in both phenolic content and antifouling activity were highlighted, and seasonal variation in both those characters was also observed. For both experiments, pneumatocyst and leaflet phenolic extracts were the most active against the attachment of Perna perna, but no correlation was observed between phenolic concentration and antifouling activity. On the contrary, the extract containing only phenolic compounds was twice less active than the extract from which 80 % of the polyphenols were removed. These results led us to hypothesise that polar compounds other than polyphenols are involved in the antifouling activity. [ABSTRACT FROM AUTHOR]

The Sargasso Sea, named due to the floating presence of Sargassum fluitans and S. natans, is usually reported for the tropical region of the Northern Hemisphere. On 14 July 2011, at 02°45' N and 48°28' W, samples of pelagic seaweed masses were collected by the Patrol Ship Bracuí of the Brazilian Navy. The seaweed was identified as S. natans, previously considered as of doubtful occurrence in Brazil. [ABSTRACT FROM AUTHOR]

Kappaphycus alvarezii commercial cultivation is increasing along Brazilian coast. After 2008, more than 30 farms were established at Rio de Janeiro state in Sepetiba and Ilha Grande bays. Each farm has about ten floating rafts corresponding to near 900 m of cultivation line. Understanding the effect of the environmental factors on the growth and carrageenan yield and quality of the target algae in commercial farms will subsidize the establishment of efficient management activities to be used in the farms. In this sense, the temporal variation of the K. alvarezii daily growth rate, productivity, carrageenan yield, and quality (viscosity and gel strength) were analyzed using the seedlings cultivated in the largest Brazilian commercial cultivation at Sepetiba Bay. The daily growth rate, productivity, and carrageenan yield and quality were within the commercial requirement desirable for commercial crops. The main factors that caused the breakage of the floating rafts and consequently diminished the productivity are the storms. Water temperature and salinity were the other factors that influenced the daily growth rate and carrageenan yield and quality. [ABSTRACT FROM AUTHOR]

Abstract: The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon–Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities. [Copyright &y& Elsevier]

Hyphenated techniques of gas chromatography coupled to mass spectrometer were used to determine fatty acids in eleven species of seaweeds from Fernando de Noronha archipelago. The main compounds detected in all studied species were the alcohol phytol and the fatty acids 14 : 0; 15 : 0; 16 : 0; 18 : 0; 18 : 1 n9; 18:2 Δ9,12; 20 : 4; 20 : 5. These fatty acids are commonly found in seaweeds present in warm regions. Thus, we found no specificity in the presence of a particular set of fatty acids and the studied species indicating that they are not useful as taxonomic indicators. However, they could be used in a comparative study with algae found in polluted area because many of the studied seaweeds are widespread and Fernando de Noronha has low human influence. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Integrated Coastal Zone Management / Revista de Gestão Costeira Integrada is the property of Associacao Portuguesa dos Recursos Hidricos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se describen las poblaciones de las macroalgas submareales predominantemente tropicales que crecen sobre rodolitos entre 4 y 18 m de profundidad en la parte sur del estado de Espírito Santo (Brasil). Muestreos cualitativos y cuantitativos revelaron comunidades ricas en especies de algas, incluyendo 167 especies. Tres especies de rodofitas son nuevas adiciones a la flora marina de Brasil (Lithothamnion muelleri, Scinaia aborealis y Mesophyllum engelhartii). Las marcadas diferencias estacionales en la composición y abundancia de especies de algas carnosas se relacionaron con la inestabilidad causada por el disturbio de tormentas invernales sobre los mantos de rodolitos. En cuanto a la profundidad, la densidad de rodolitos parece ser un factor importante para la variación en la abundancia de algas carnosas. La comunidad de rodolitos está formada por al menos siete especies de algas coralinas no geniculadas. Se demostró que los mantos de rodolitos, en un área de 150 km2, proporcionan un hábitat importante para las comunidades bentónicas, manteniendo 25% de la riqueza de especies de macroalgas conocidas para la costa brasileña. [ABSTRACT FROM AUTHOR]

This study describes the predominantly tropical, subtidal seaweed populations growing on rhodoliths between 4 and 18 m depth in the southern part of Espírito Santo State (Brazil). Qualitative and quantitative sampling revealed species-rich algal communities, comprising 167 species. Three species of rhodophytes represent new records for the Brazilian marine flora (Lithothamnion muelleri, Scinaia aborealis, and Mesophyllum engelhartii). Marked seasonal differences in fleshy algal species composition and abundance were related to seasonal instabilities caused by winter-storm disturbance over the rhodolith beds. In relation to depth, rhodolith density appears to be an important factor for the variation in the abundance of fleshy algae. The rhodolith community is composed of at least seven nongeniculate crustose coralline algal species. Rhodolith beds in southern Espírito Santo State, in an area of 150 km2, provide an important habitat for epibenthic communities, supporting 25% of the known macroalgal species richness along the Brazilian coast. [ABSTRACT FROM AUTHOR]

Nongeniculate Corallinaceae are poorly known in Brazil. In our endeavor to identify this group of seaweeds along the Brazilian coast we came across some specimens that fit well into the accepted circumscription of Litothamnion Heydrich. Within this genus they could be identified to what has been called L. superpositum Foslie. The specimens were represented by nongeniculate, free living specimens (rhodoliths); lumpy to fruticose growth-form, presenting flared epithallial cells in transversal section; multiporate tetrasporangial conceptacles, with roof protruding above or flush with the surrounding thallus surface; chambers 250–525 µm in diameter and 150–230 µm high, roof structured by filaments with 3–5 cells long; and pores in depression. Among the species described from the Brazilian coast, L. heteromorphum (Foslie) Foslie presented anatomical and reproductive characteristics similar to the referred species described from southern Africa and Australia. Therefore, we propose to consider L. heteromorphum as a heterotypic synonym of L. superpositum and extending its distribution to the Western Atlantic. [ABSTRACT FROM AUTHOR]

This article presents an evaluation of the importance of algal palynomorphs for palaeoenvironmental and climatic reconstructions. The palynomorphs were identified in sediments formed during the 20th century in the Tramandañ Lagoon (southern Brazil). The sediments sample corresponds to the 1905-97 period as dated by 210Pb. Five algal palynomorph zones (IA-VA) were defined based on Botryococcus : and Pediastrum frequency of occurrence ratio as well as on the presence of other freshwater algal palynomorphs. The sensitiveness of algal Chlorophyta palynomorphs to environmental variables, such as temperature and salinity, reveals that these palynomorph zones are related to five major stages of the Tramandaí Lagoon's evolution, reflecting variations in the regional hydrological cycle. The last identified stage (VA) is characterized by a notable increase in marine algae and a decrease in freshwater algal palynomorphs. This marine algal palynomorph enrichment was caused by an increase in sea water influx as a result of the construction of an artificial channel connecting the lagoon with the Atlantic Ocean. The obtained results on algal palynomorph frequencies of occurrence were compared with available records of water-level measurements from the coastal Mirim Lagoon, situated relatively close to the Tramandaí Lagoon, and to the Southern Oscillation Index of the Australian Bureau of Meteorology. Wetter/drier periods of the past century as revealed by algal palynomorph frequencies generally coincide with low-frequency water-level oscillations in the Mirim Lagoon and are probably related to interannual variations of rainfall in the region, driven by the variability of the El Niño-Southern Oscillation phenomena. [ABSTRACT FROM AUTHOR]

This study, performed over the years 1999–2003, analyzed the species composition, spatial distribution and ecological aspects of macroalgal assemblages on Atol das Rocas reef, located 266 km off northeastern Brazil. It is the sole atoll in the South Atlantic and is almost completely built of coralline algae. Forty-seven new occurrences of macroalgae were recorded. Adding these to the previous studies, 143 taxa are now known for the local marine flora, with the Rhodophyta as the dominant group. New finds were mainly on the fore reef and in reef pools. The inner habitats (the reef flat, internal ridge and inner pools) harbored fewer macroalgal species than the outer habitats (the reef front, reef crest crevices and outer pools). Inner habitats are subject to prolonged desiccation and solar irradiation stress together with abrupt changes in temperature and salinity controlled by the water oscillations of the mesotidal regime within the atoll; the outer habitats are less affected by these short temporal impacts and are mainly governed by oceanic forcing. Atol das Rocas harbors some species unknown in other Brazilian waters, but these are common in Caribbean reef waters. [ABSTRACT FROM AUTHOR]

Hippolyte obliquimanus is a small, gonochoric shrimp found in algal substrates along the western Atlantic coast of Brazil, particularly in association with seaweed of the genus Sargassum. We studied population features (sexual ratio, reproductive period and temporal distribution) of H. obliquimanus in southeastern Brazil, including its relationships with the seasonality of banks of this alga. Specimens were collected at two-monthly intervals from March 2005 to January 2006, in Ubatuba Bay. The sex of individuals was checked, and the carapace length measured. In total, 668 individuals were collected: 211 males (0.70-2.50 mm carapace length), 341 non-ovigerous females (0.55-2.90 mm), and 116 ovigerous females (1.55-3.20 mm). Hippolyte obliquimanus showed seasonal-continuous reproduction and variable continuous recruitment. The highest number of animals (75%) was collected in fall-winter. The percentages of ovigerous females/total females (fall-winter: 27%; spring-summer: 26%) and the sexual ratio (fall-winter: 31%; spring-summer: 32%) were practically equal in both periods. The sexual ratio showed a predominance of females in almost all size classes, and we detected a new sex ratio pattern for this species. The seasonal variation in the number of individuals can be related to its migration to deeper areas, due to the decrease in the abundance of Sargassum sp. in shallower waters in spring-summer. [ABSTRACT FROM AUTHOR]

Abstract: Sulfated polysaccharides from 11 species of tropical marine algae (one edible specie of Rhodophyta, six species of Phaeophyta and four species of Chlorophyta) collected from Natal city coast (Northeast of Brazil) were evaluated for their anticoagulant, antioxidant and antiproliverative in vitro activities. In the activated partial thromboplastin time (APTT) test, which evaluates the intrinsic coagulation pathway, seven seaweeds presented anticoagulant activity. Dictyota cervicornis showed the highest activity, prolonging the coagulation time to double the baseline value in the APTT with only 0.01mg/100μl of plasma, 1.4-fold lesser than Clexane®, a low molecular weight heparin. In the protrombin time (PT) test, which evaluates the extrinsic coagulation pathway, only Caulerpa cupresoides showed anticoagulant activity. All species collected showed antioxidant activities. This screening emphasized the great antioxidant potential (total capacity antioxidant, power reducing and ferrous chelating) of four species: C. sertularioide; Dictyota cervicornis; Sargassum filipendula and Dictyopteris delicatula. After 72h incubation, HeLa cell proliferation was inhibited (p <0.05) between 33.0 and 67.5% by S. filipendula; 31.4 and 65.7% by D. delicatula; 36.3 and 58.4% by Caulerpa prolifera and 40.2 and 61.0% by Dictyota menstrualis at 0.01–2mg/mL algal polysaccharides. The antiproliferative efficacy of these algal polysaccharides were positively correlated with the sulfate content (r =0.934). Several polysaccharides demonstrated promising antioxidant, antiproliferative an/or anticoagulant potential and have been selected for further studies on bioguided fractionation, isolation and characterization of pure polysaccharides from these species as well as in vivo experiments are needed and are already in progress. [Copyright &y& Elsevier]

Copyright of Revista do Instituto de Medicina Tropical de São Paulo is the property of Instituto de Medicina Tropical de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract??During the last two decades, the monostromatic green seaweedGayraliasp. has been harvested sporadically by local fishermen on the Paran? coast of southern Brazil and sold to Japanese restaurants. However, the production is erratic and its economic impact very small. This paper provides basic information about a technique to cultivate this seaweed on suspended nets in Paranagu? Bay, southern Brazil, aiming to develop a more reliable and sustainable source of income for impoverished coastal dwellers.Gayraliasp. occurs year round in the region, usually growing on mangrove stems and roots. Polypropylene nets (10?m long ? 1?m wide with 16?cm mesh) were placed close to the mangrove fringe. Recruitment occurred year round reaching a peak of 500 recruits m?2during early spring. Higher recruitment occurred at periods of low temperature (21?23?C) and high salinity (30?33 psu). Growth rates ofGayraliasp. ranged from 5.75 ? 0.56% to 6.50 ? 0.43% day?1during the winter and from 1.43 ? 1.65% to 4.65 ? 2.17% day?1, during the summer. Production ranged from 22 ? 6?g m?2DW in June to 58 ? 21?g m?2DW in September 2004 in 45 days after zooid settlement. The simplicity of the cultivation method, reasonable growth rates and extensive favorable area for cultivation suggest that mariculture ofGayraliasp. may become a good alternative of income for the local inhabitants. [ABSTRACT FROM AUTHOR]

The nematofauna from the seaweeds Sargassum polyceratium Montagne, Hypnea musciformis Küetzing, Padina gymnospora Küetzing and the seagrass Halodule wrightii Ascherson was studied in March 2001, at Pedra do Xaréu, Pernambuco, Brazil, in order to investigate the associations of organisms, as well as the relation between the plant architecture and the associated fauna. Soft sediments adjacent to phytal environments were also investigated. Thirty-eight genera were found, including two new records (Odontanticoma sp. and Wieseria sp.) for the Brazilian coast. Multivariate analyses were carried out in order to verify the relation between nematode assemblages on plants and in sediments. The results showed that these assemblages were different in structure and composition between macrophytes and sediments. They were different in structure but not in composition among macrophytes, so the nematode biodiversity was related to the structural features of macrophytes’ habitats. [ABSTRACT FROM AUTHOR]

The Abrolhos region of Brazil is recognized for its ecological importance and richness of endemic species. Between Redonda and Siriba, two small islands in the Abrolhos archipelago, there are dense populations of macroalgae associated with seagrass (Halodule wrightii) beds. Samples of the community were collected by SCUBA divers in August and December 1995 and April 1996. Forty­nine taxa of macroalgae were found associated with the seagrass at the study site. Nine macroalgae were recorded for the first time for the Abrolhos National Marine Park and four taxa are reported for the first time for Bahia State. Macroalgae were found growing on dead corals and rocks, as epiphytes on incrusting calcareous algae (rhodoliths or maerls), as epiphytes on Udotea flabellum, episamic, or growing unattached. In terms of richness per substratum: unattached > on calcareous algae, epilithic or on Udotea > episamic. In terms of biomass per substratum: episamic > unattached > on Udotea > epilithic > on calcareous algae. No significant differences in richness were found between times, but macroalgal diversity and evenness were greater in August 1995 than at other times. The seagrass biomass did not vary seasonally but the seaweed biomass did. Seagrass was the largest component of macrophyte biomass in August 1995 and April 1996. However, in December 1995 macroalgal biomass was double that of the seagrass and was significantly higher than in August 1995. Rhodophyta was the richest division > Phaeophyta > Chlorophyta. The macroalgal community in the seagrass beds at Abrolhos was considered to be rich and diverse and contained a disproportionately high number of taxa of Phaeophyta (19%), when compared to the whole Brazilian flora. [ABSTRACT FROM AUTHOR]

We compare `temperate data' with information contained in 49 surveys of cryptomonads from Brazilian tropical regions. These surveys contain a total of 351 records relative to a total of 38 taxa at the species level or below. All taxa were identified using traditional morphological characters visible with the light microscope. Two taxa appear to be new species, and amongst the known species Cryptomonas erosa Ehrenberg is the most frequently recorded one. To date two species of Pseudocryptomonas Bicudo & Tell (all containing multiple photosynthetic endosymbionts/chloroplasts) and the species Cryptomonas brasiliensis Castro, C. Bicudo & D. Bicudo have not been found outside Brazil. With respect to their geographical distribution in Brazilian tropical regions, cryptomonads are better represented in reservoirs and coastal lagoons located in the south-eastern part of the country. Some species appear to be restricted to brackish coastal ecosystems (oligo- to mesohaline and meso- to eutrophic waters). There are only four records of marine cryptomonads. A comparative study of three different kinds of shallow aquatic environments in Brazil – north-eastern reservoirs, a flood-plain Amazonian lake, and brackish lagoons on the south-eastern coast – shows that cryptomonads are to be found constantly, and their species number density, and biomass are generally low (usually <10%) in relation to the other phytoplankton. The case of Plagioselmis Butcher emend. Novarino, Lucas & Morrall, amongst others, exemplifies the great difficulties encountered while attempting to interpret biogeographical information based on light microscopy within the context of a modern systematic and taxonomic framework based on electron microscopy. [ABSTRACT FROM AUTHOR]