25 resultados para Hypnea musciformis


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Hypnea musciformis (Wulfen in Jacqu.) J.V. Lamour. is the main source for carrageenan production in Brazil and strains with selected characteristics could improve the production of raw material. The effects of kinetin on growth rates, morphology, protein content, and concentrations of pigments (chlorophyll a, phycoerythrin, phycocyanin, and allophycocyanin) were assessed in the wild strain (brown phenotype) and in the phycoerythrin-deficient strain (green phenotype) of H. musciformis. Concentrations of kinetin ranging from 0 to 50 mu M were tested in ASP 12-NTA synthetic medium with 10 mu M nitrate (N-limited) and 100 mu M nitrate (N-saturated). In N-limited condition, kinetin stimulated growth rates of the phycoerythrin-deficient strain and formation of lateral branches in both colour strains. Kinetin stimulated protein biosynthesis in both strains. However, differences between both nitrogen conditions were significant only in the phycoerythrin-deficient strain. In the wild strain, effects of kinetin on concentrations of phycobiliproteins were not significant in both nitrogen conditions, except for chlorophyll content. However, the phycoerythrin-deficient strain showed an opposite response, and kinetin stimulated the phycobiliprotein biosynthesis, with the highest concentrations of phycoerythrin in N-saturated medium, while the highest concentrations of allophycocyanin and phycocyanin were observed in N-limited medium. These results indicate that the effects of kinetin on growth, morphology, protein and phycobiliprotein contents are influenced by nitrogen availability, and the main nitrogen storage pools in phycoerythrin-deficient strain of H. musciformis submitted to N-limited conditions were phycocyanin and allophycocianin, the biosynthesis of which was enhanced by kinetin.

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Marine algae are one of the major sources of biologic compounds. In extracellular matrix of these organisms there are sulfated polysaccharides that functions as structural components and provides protection against dehydration. The fraction 1.0 (F1.0) rich in sulfated galactans obtained from red seaweed Hypnea musciformis was physicochemical characterized and evaluated for pharmacologic activity through antioxidant activity, cytotoxic action on erythrocytes, anticoagulant, stimulatory action under antithrombotic heparan sulfate synthesis and their effects on cell proliferation and cycle cell progression. The main components of F1.0 were carbohydrates (49.70 ± 0.10%) and sulfate (44.59 ± 0.015%), presenting phenolic compounds (4.79 ± 0.016%) and low protein contamination (0.92 ± 0.001%). Fraction 1.0 showed polidisperse profile and signs in infrared analysis in 1262, 1074 and 930, 900 and 850 attributed to sulfate esters S=O bond, presence of a 3,6- anidrogalactose C-O bond, non-sulfated β-D-galactose and a C-O-SO4 bond in galactose C4, respectively. The fraction rich in sulfated galactans exhibited strong antioxidant action under lipid peroxidation assay with IC50 of 0.003 mg/mL. Besides the inhibition of hemolysis induced by H2O2 in erythrocytes treated with F1.0, this fraction did not promote significant cytotoxity under erythrocytes membranes. F1.0 exhibited low anticoagulant activity causing moderate direct inhibition of enzimatic activity of thrombin. This fraction promoted stimulation around of 4.6 times on this synthesis of heparan sulfate (HS) by rabbit aortic endothelial cells (RAEC) in culture when was compared with non treated cells. The fraction of this algae displayed antiproliferative action under RAEC cells causing incresing on cell number on S fase, blocking the cycle cell progression. Thus F1.0 presented cytostatic and no cytotoxic action under this cell lineage. These results suggest that F1.0 from H. musciformis have antioxidant potential which is a great effect for a compound used as food and in food industry which could be an alternative to food industry to prevent quality decay of lipid containing food due to lipid peroxidation. These polysaccharides prevent the lipid peroxidation once the fraction in study exhibited strong inhibitory action of this process. Furthermore that F1.0 present strong antithrombotic action promoting the stimulation of antithrombotic HS synthesis by endothelial cells, being important for thrombosis preventing, by its inhibitory action under reactive oxygen species (ROS) in some in vitro methods, being involved in promotion of hypercoagulability state.

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The phycoerythrin-deficient strain (green phenotype) of Hypnea musciformis (Rhodophyta) originated from a green branch, which had arisen as a spontaneous mutation in a wild plant (brown phenotype) collected from the Brazilian coast. The present study describes the growth responses to irradiance, photoperiod and temperature variations, pigment contents, and photosynthetic characteristics of the brown and green strains of H. musciformis. The results showed that growth rates increased as a function of irradiance (up to 40 mu mol photons m(-2) s(-1)) but, with further increase in irradiance (from 40 to 120 mu mol photons m(-2) s(-1)), became light-saturated and remained almost unchanged. The highest growth rates of the brown and green strains were observed in temperatures of 20-25 degrees C under long (14:10 h LD) and short (10:14 h LD) photoperiods. The brown strain had higher growth rates than the green strain in the short photoperiod, which could be related to the high concentrations of phycobiliproteins. Phycoerythrin was not detected in the green strain. The brown strain had higher concentrations of allophycocyanin and phycoerythrin in the short photoperiod while the green strain had higher concentrations of phycocyanin. The brown strain presented higher photosynthetic efficiency (alpha), and lower saturation parameter (I-k) and compensation irradiance (I-c) than the green strain. The brown strain exhibited the characteristics of shade-adapted plants, and its higher value of photosynthetic efficiency could be attributed to the higher phycoerythrin concentrations. Results of the present study indicate that both colour strains of H. musciformis could be selected for aquaculture, since growth rates were similar (although in different optimal light conditions), as the green strain seems to be adapted to higher light levels than the brown strain. Furthermore, these colour strains could be a useful experimental system to understand the regulation of biochemical processes of photosynthesis and metabolism of light-harvesting pigments in red algae.

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Marine algae are one of the major sources of biologic compounds. In extracellular matrix of these organisms there are sulfated polysaccharides that functions as structural components and provides protection against dehydration. The fraction 1.0 (F1.0) rich in sulfated galactans obtained from red seaweed Hypnea musciformis was physicochemical characterized and evaluated for pharmacologic activity through antioxidant activity, cytotoxic action on erythrocytes, anticoagulant, stimulatory action under antithrombotic heparan sulfate synthesis and their effects on cell proliferation and cycle cell progression. The main components of F1.0 were carbohydrates (49.70 ± 0.10%) and sulfate (44.59 ± 0.015%), presenting phenolic compounds (4.79 ± 0.016%) and low protein contamination (0.92 ± 0.001%). Fraction 1.0 showed polidisperse profile and signs in infrared analysis in 1262, 1074 and 930, 900 and 850 attributed to sulfate esters S=O bond, presence of a 3,6- anidrogalactose C-O bond, non-sulfated β-D-galactose and a C-O-SO4 bond in galactose C4, respectively. The fraction rich in sulfated galactans exhibited strong antioxidant action under lipid peroxidation assay with IC50 of 0.003 mg/mL. Besides the inhibition of hemolysis induced by H2O2 in erythrocytes treated with F1.0, this fraction did not promote significant cytotoxity under erythrocytes membranes. F1.0 exhibited low anticoagulant activity causing moderate direct inhibition of enzimatic activity of thrombin. This fraction promoted stimulation around of 4.6 times on this synthesis of heparan sulfate (HS) by rabbit aortic endothelial cells (RAEC) in culture when was compared with non treated cells. The fraction of this algae displayed antiproliferative action under RAEC cells causing incresing on cell number on S fase, blocking the cycle cell progression. Thus F1.0 presented cytostatic and no cytotoxic action under this cell lineage. These results suggest that F1.0 from H. musciformis have antioxidant potential which is a great effect for a compound used as food and in food industry which could be an alternative to food industry to prevent quality decay of lipid containing food due to lipid peroxidation. These polysaccharides prevent the lipid peroxidation once the fraction in study exhibited strong inhibitory action of this process. Furthermore that F1.0 present strong antithrombotic action promoting the stimulation of antithrombotic HS synthesis by endothelial cells, being important for thrombosis preventing, by its inhibitory action under reactive oxygen species (ROS) in some in vitro methods, being involved in promotion of hypercoagulability state.

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Hypnea musciformis (Wulf.) Lamour., H. pannosa J. Ag. and H. valentiae (Turn.) Mont., collected from the northern Arabian Sea coast of Pakistan, have been investigated for their fatty acid compositions through GC-MS. Palmitic acid was present in largest quantity (55-57%) and oleic was the major (7.6-8.4%) unsaturated fatty acid. Pentacosanoic and hexacosenoic acids are being reported for the first time from any species of Hypnea. The three species differed remarkably due to their habitat ecology.

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This report describes a surveillance strategy to detect deepwater invasive species in the Northwestern Hawaiian Islands. A need for this strategy was identified in the Papahānaumokuākea Marine National Monument Management Plan and the Monument’s Draft Natural Resources Science Plan. This strategy focuses on detecting two species of concern, the octocoral Carijoa riisei and the red alga Hypnea musciformis. Most research on invasive species in the Hawaiian archipelago has focused on shallow water habitats within the limits of conventional SCUBA (0-30 m). Deeper habitats such as mesophotic reefs are much more difficult to access and consequently little is known about the distribution of deepwater invasive species or their impacts. Recent deepwater (>30 m) sightings of H. musciformis and C. riisei, in and near NWHI, respectively, have prompted a call for further research and surveillance of invasive species in deepwater habitats. This report compiles the most up to date information about these two species of concern in deepwater habitats. A literature search and conversations with subject matter experts was used to identify their current distribution, preferred habitat types, optimal detection methods and ways to efficiently sample the vast extent of NWHI. The proposed sampling strategy prioritizes survey effort where C. riisei and H. musciformis are most likely to be found. At coarse spatial scales (tens to hundreds of kilometers), opportunistic observations and distance from the Main Hawaiian Islands, a principal propagule source, are used to identify high-risk islands and banks. At fine spatial scales (meters to tens of kilometers) a habitat suitability model was developed to identify high-risk habitats. The habitat suitability model focused on habitat preferences of C. riisei, since the species is well studied and adequate data exists to map habitats. There was insufficient information to identify suitable habitat for H. muscifomis. Habitat preferences for the algae are poorly understood and there is a lack of data at relevant spatial scales to map those preferences which are known. The principal habitats identified by the habitat suitability model were ledges and the edges of rugose coral reefs, where the shade loving octocoral would likely be found. Habitat suitability maps were developed for seven atolls and banks to aid in survey site selection. The protocol relied on technical divers to conduct visual surveys of benthic habitats. It was developed to increase the efficiency of surveys, maximize the probability of detection, identify important information relevant to future surveys and standardize results. The strategy, model and protocol were tested during a field mission in 2009 at several atolls and islands in NWHI. The field mission did not detect any invasive species among deepwater habitats and much was learned to improve future surveys. Data gaps and improvements are discussed.

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Nonindigenous species (NIS) are a major threat to marine ecosystems, with possible dramatic effects on biodiversity, biological productivity, habitat structure and fisheries. The Papahānaumokuākea Marine National Monument (PMNM) has taken active steps to mitigate the threats of NIS in Northwestern Hawaiian Islands (NWHI). Of particular concern are the 13 NIS already detected in NWHI and two invasive species found among the main Hawaiian Islands, snowflake coral (Carijoa riseii) and a red alga (Hypnea musciformis). Much of the information regarding NIS in NWHI has been collected or informed by surveys using conventional SCUBA or fishing gear. These technologies have significant drawbacks. SCUBA is generally constrained to depths shallower than 40 m and several NIS of concern have been detected well below this limit (e.g., L. kasmira – 256 m) and fishing gear is highly selective. Consequently, not all habitats or species can be properly represented. Effective management of NIS requires knowledge of their spatial distribution and abundance over their entire range. Surveys which provide this requisite information can be expensive, especially in the marine environment and even more so in deepwater. Technologies which minimize costs, increase the probability of detection and are capable of satisfying multiple objectives simultaneously are desired. This report examines survey technologies, with a focus on towed camera systems (TCSs), and modeling techniques which can increase NIS detection and sampling efficiency in deepwater habitats of NWHI; thus filling a critical data gap in present datasets. A pilot study conducted in 2008 at French Frigate Shoals and Brooks Banks was used to investigate the application of TCSs for surveying NIS in habitats deeper than 40 m. Cost and data quality were assessed. Over 100 hours of video was collected, in which 124 sightings of NIS were made among benthic habitats from 20 to 250 m. Most sightings were of a single cosmopolitan species, Lutjanus kasmira, but Cephalopholis argus, and Lutjanus fulvus, were also detected. The data expand the spatial distributions of observed NIS into deepwater habitats, identify algal plain as an important habitat and complement existing data collected using SCUBA and fishing gear. The technology’s principal drawback was its inability to identify organisms of particular concern, such as Carijoa riseii and Hypnea musciformis due to inadequate camera resolution and inability to thoroughly inspect sites. To solve this issue we recommend incorporating high-resolution cameras into TCSs, or using alternative technologies, such as technical SCUBA diving or remotely operated vehicles, in place of TCSs. We compared several different survey technologies by cost and their ability to detect NIS and these results are summarized in Table 3.

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This protocol was developed by the Biogeography Branch of NOAA’s Center for Coastal Monitoring and Assessment to support invasive species research by the Papahānaumokuākea Marine National Monument. The protocol’s objective is to detect Carijoa riisei and Hypnea musciformis in deepwater habitats using visual surveys by technical divers. Note: This protocol is designed to detect the presence or absence of invasive species. A distinct protocol is required to collect information on abundance and impact, or monitor changes over time.

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Studies on sporulation of four commercially important red (sea-weeds) algae ^(agarophytes) namely Gelidiella acerosa, Gracilaria corticata, G edulis and Hypnea musciformis growing in the vicinity of’ Mandapam coast were carried out from October 1981 to September 1983. During the two years of study; fruiting behavior in the natural population of these species was also investigated. Laboratory experiments were carried out with the four algae sea weeds to collect information on seasonal aspects of spore production and diurnal variation of spore shedding. Detailed studies were made under laboratory conditions to know the effects of some selected environmental factors such as desiccation, salinity, temperature, light intensity and photoperiod on spore output in Gelidiella acerosa, Gracilaria edulis and kypnea musciformis hydrological data were also collected from the inter-tial region around mandapam area. The result obtained on all the above aspects are presented in this thesis

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The hydroid Zyzzyzus warreni is usually found in shallow coastal waters forming aggregations of solitary polyps embedded in demosponges. Early life history transformations and settlement responses by the actinulae of this hydroid were studied in the laboratory using 13 species of sponges and 2 species of algae collected in the Sao Sebastiao Channel (Brazil) as substrata. The absence of oral tentacles and mouth in the actinulae and early events of metamorphosis suggest that these larvae are unable to spend long periods in the plankton and attach quickly near conspecifics when a preferred substratum is encountered. The time required for settlement and the number of elicited settlings indicated four settlement responses: (a) frequent and short-time settlement, in actinulae exposed to Halichondria cebimarensis, Mycale angulosa, M. aff. americana, M. laxissima (skeleton) and Tedania ignis; (b) moderate and delayed settlement, in actinulae exposed to Aplysina caissara, A. fulva, Haliclona melana and M. microsigmatosa; (c) no settlement, in actinulae exposed to Suberites aurantiacus and to the algae Hypnea musciformis and Sargassum cymosum; and (d) lethal response, in actinulae exposed to Amphimedon viridis, Aplysilla rosea, Dragmacidon reticulatum and M. laxissima. These responses indicate a considerable degree of species discrimination by the actinulae and are consistent with substrata used by the hydroid in the natural environment.

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Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen) J.V. Lamouroux (Rhodophya), Sargassum cymosum C. Agardh (Heterokontophyta), and Ulva lactuca L. (Chlorophyta), comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU) and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl). The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

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Máster Oficial en Cultivos Marinos. Trabajo presentado como requisito parcial para la obtención del Título de Máster Oficial en Cultivos Marinos, otorgado por la Universidad de Las Palmas de Gran Canaria (ULPGC), el Instituto Canario de Ciencias Marinas (ICCM), y el Centro Internacional de Altos Estudios Agronómicos Mediterráneos de Zaragoza (CIHEAM)