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Sample records for algae fucus vesiculosus

  1. Consumption and feeding preference of Echinogammarus marinus on two different algae: Fucus vesiculosus and Ulva intestinalis

    NASA Astrophysics Data System (ADS)

    Martins, Irene; Leite, Nuno; Constantino, Emanuel

    2014-01-01

    Echinogammarus marinus constitutes the most abundant amphipod species in Fucus spp. assemblages from many North Atlantic estuaries. However, there are some doubts about the real use of fucoids by the amphipod. Whilst some studies report the ingestion of Fucus vesiculosus by E. marinus, others suggest that the amphipod preference for fucoids is mostly related to sheltering rather than feeding, due to the high phlorotannin content of brown algae. The purpose of the present work was to disentangle this issue by checking the consumption rate and feeding preference of E. marinus on F. vesiculosus, its preferential habitat, and on Ulva intestinalis, a green algae abundant in the Mondego estuary (Western Coast of Portugal) and usually considered as highly palatable for herbivores. In a 2-stage laboratorial setup, fresh disks of the two types of algae were offered to E. marinus for three days. Consumption rates were estimated from differences between algal and animal initial and final fresh weights using a control correction factor, while preference was tested by differences in algal consumption rates when no choice was offered (stage 1) and when the two algae were offered simultaneously (stage 2). Results showed that E. marinus effectively consumed fresh F. vesiculosus in much higher amounts than U. intestinalis and significantly preferred to consume F. vesiculosus over U. intestinalis. Therefore, feeding habits must be one of the factors related to the close association of the amphipod with F. vesiculosus, although other factors may also be involved (e.g. sheltering).

  2. Nodularin induces oxidative stress in the Baltic Sea brown alga Fucus vesiculosus (Phaeophyceae).

    PubMed

    Pflugmacher, Stephan; Olin, Miikka; Kankaanpää, Harri

    2007-08-01

    In the Baltic Sea regular, intensive cyanobacterial blooms rich in the cyanobacterium Nodularia spumigena occur during the summer season. N. spumigena is known to produce the cyclic pentapeptide nodularin (NOD) in high concentrations. Marine macroalgae, together with sea-grass meadows, are an extremely important habitat for life in the sea. In addition to this, the decaying macroalgae substantially contribute to the substrate for the microbial loop in coastal food webs. Uptake of nodularin into the brown macroalga Fucus vesiculosus was assessed using an ELISA technique resulting in an uptake of up to 45.1 microg kg(-1) fresh weight (fw). Nodularin was also detected in the reproductive part of the algae (receptacle) at 14.1 microg kg(-1) fw. The induction of oxidative stress in F. vesiculosus, after exposure to NOD, was also shown by monitoring cellular damage as changes in lipid peroxidation and the activation of antioxidative defence systems (antioxidative capacity, superoxide dismutase and soluble glutathione S-transferase).

  3. Dimethylsulphopropionate (DMSP) and proline from the surface of the brown alga Fucus vesiculosus inhibit bacterial attachment.

    PubMed

    Saha, M; Rempt, M; Gebser, B; Grueneberg, J; Pohnert, G; Weinberger, F

    2012-01-01

    It was demonstrated previously that polar and non-polar surface extracts of the brown alga Fucus vesiculosus collected during winter from the Kiel Bight (Germany) inhibited bacterial attachment at natural concentrations. The present study describes the bioassay-guided identification of the active metabolites from the polar fraction. Chromatographic separation on a size-exclusion liquid chromatography column and bioassays identified an active fraction that was further investigated using nuclear magnetic resonance spectroscopy and mass spectrometry. This fraction contained the metabolites dimethylsulphopropionate (DMSP), proline and alanine. DMSP and proline caused the anti-attachment activity. The metabolites were further quantified on the algal surface together with its associated boundary layer. DMSP and proline were detected in the range 0.12-1.08 ng cm(-2) and 0.09-0.59 ng cm(-2), respectively. These metabolites were tested in the concentration range from 0.1 to 1000 ng cm(-2) against the attachment of five bacterial strains isolated from algae and sediment co-occurring with F. vesiculosus. The surface concentrations for 50% inhibition of attachment of these strains were always <0.38 ng cm(-2) for DMSP and in four cases <0.1 ng cm(-2) for proline, while one strain required 1.66 ng cm(-2) of proline for 50% inhibition. Two further bacterial strains that had been directly isolated from F. vesiculosus were also tested, but proved to be the least sensitive. This study shows that DMSP and proline have an ecologically relevant role as surface inhibitors against bacterial attachment on F. vesiculosus.

  4. Genotypic variation in tolerance and resistance to fouling in the brown alga Fucus vesiculosus.

    PubMed

    Honkanen, Tuija; Jormalainen, Veijo

    2005-06-01

    In this study, we examined genetic variation in resistance and tolerance to fouling organisms in the brown alga Fucus vesiculosus. We first grew 30 algal genotypes in the field, where we allowed fouling organisms to colonise the genotypes at natural levels. We then conducted a manipulative experiment, where we grew 20 genotypes of algae in aquaria with or without fouling organisms. We measured host resistance as the load of fouling organisms and tolerance as the slope of the regression of algal performance on fouling level. Fouling organisms decreased host growth and contents of phlorotannins and thus have the potential to act as selective agents on algal defenses. We found significant among-genotype variation in both resistance and tolerance to fouling. We did not find a trade-off between resistance and tolerance. We found a marginally significant cost of resistance, but no cost of tolerance. Our results thus indicate that both the tolerance and resistance of F. vesiculosus can evolve as a response to fouling and that the costs of resistance may maintain genetic variation in resistance.

  5. Fouling mediates grazing: intertwining of resistances to multiple enemies in the brown alga Fucus vesiculosus.

    PubMed

    Jormalainen, Veijo; Wikström, Sofia A; Honkanen, Tuija

    2008-03-01

    Macroalgae have to cope with multiple natural enemies, such as herbivores and epibionts. As these are harmful for the host, the host is expected to show resistance to them. Evolution of resistance is complicated by the interactions among the enemies and the genetic correlations among resistances to different enemies. Here, we explored genetic variation in resistance to epibiosis and herbivory in the brown alga Fucus vesiculosus, both under conditions where the enemies coexisted and where they were isolated. F. vesiculosus showed substantial genetic variation in the resistance to both epibiosis and grazing. Grazing pressure on the alga was generally lower in the presence than in the absence of epibiota. Furthermore, epibiosis modified the susceptibility of different algal genotypes to grazing. Resistances to epibiosis and grazing were independent when measured separately for both enemies but positively correlated when both these enemies coexisted. Thus, when the enemies coexisted, the fate of genotypes with respect to these enemies was intertwined. Genotypic correlation between phlorotannins, brown-algal phenolic secondary metabolites, and the amount of epibiota was negative, indicating that these compounds contribute to resistance to epibiosis. In addition, phlorotannins correlated also with the resistance to grazing, but this correlation disappeared when grazing occurred in the absence of epibiota. This indicates that the patterns of selection for the type of the resistance as well as for the resistance traits vary with the occurrence patterns of the enemies.

  6. Characterization of the biosorption of cadmium, lead and copper with the brown alga Fucus vesiculosus.

    PubMed

    Mata, Y N; Blázquez, M L; Ballester, A; González, F; Muñoz, J A

    2008-10-30

    The recovery of cadmium, lead and copper with the brown alga Fucus vesiculosus was characterized and quantified. The biosorption data fitted the pseudo-second order and Langmuir isotherm models, but did not adjust to the intraparticle diffusion model. The metal uptakes deduced from the pseudo-second order kinetic model and the Langmuir isotherm model followed a similar sequence: Cu>Cd approximately Pb. The Langmuir maximum metal uptakes were: 0.9626 mmol/g, Pb 1.02 mmol/g, and Cu 1.66 mmol/g. According to the equilibrium constants of this isotherm model, the affinity of metals for the biomass followed this order: Pb>Cu>Cd. Biosorption was accomplished by ion exchange between metals in solution and algal protons, calcium and other light metals, and by complexation of the adsorbed metals with algal carboxyl groups. FTIR spectra showed a shift in the bands of carboxyl, hydroxyl and sulfonate groups.

  7. Variation in natural selection for growth and phlorotannins in the brown alga Fucus vesiculosus.

    PubMed

    Jormalainen, V; Honkanen, T

    2004-07-01

    Directional selection for plant traits associated with resistance to herbivory tends to eliminate genetic variation in such traits. On the other hand, balancing selection arising from trade-offs between resistance and growth or spatially variable selection acts against the elimination of genetic variation. We explore both the amount of genetic variation and variability of natural selection for growth and concentration of phenolic secondary compounds, phlorotannins, in the brown alga Fucus vesiculosus. We measured variation in selection at two growing depths and two levels of nutrient availability in algae that had faced two kinds of past growing environments. Genetic variation was low for growth but high for phlorotannins. The form and strength of selection for both focal traits depended on the past growing environment of the algae. We found strong directional selection for growth rate in algae previously subjected to higher ultraviolet radiation, but not in algae previously subjected to higher nutrient availability. Stabilizing selection for growth occurred especially in the deep growing environment. Selection for phlorotannins was generally weak, but in some past-environment-current-environment combinations we detected either directional selection against phlorotannins or stabilizing selection. Thus, phlorotannins are not selectively neutral but affect the fitness of F. vesiculosus. In particular, there may be a fitness cost of producing phlorotannins, but the realization of such a cost varies from one environment to another. Genetic correlations between selective environments were high for growth but nonexistent for phlorotannins, emphasizing the high phenotypic plasticity of phlorotannin production. The highly heterogeneous selection, including directional, stabilizing, and spatially variable selection as well as temporal change in selection due to responses to past environmental conditions, probably maintains a high amount of genetic variation in phlorotannins

  8. Gold(III) biosorption and bioreduction with the brown alga Fucus vesiculosus.

    PubMed

    Mata, Y N; Torres, E; Blázquez, M L; Ballester, A; González, F; Muñoz, J A

    2009-07-30

    In this paper, the bioreduction of Au(III) to Au(0) using biomass of the brown alga Fucus vesiculosus was investigated. The recovery and reduction process took place in two stages with an optimum pH range of 4-9 with a maximum uptake obtained at pH 7. In the first stage, an induction period previous to gold reduction, the variation of pH, redox potential and gold concentration in solution was practically negligible and no color change was observed. In the second stage, the gold reduction was followed by a sharp decrease of gold concentration, pH and redox potential of solution and a color change from yellow to reddish purple. Hydroxyl groups present in the algal polysaccharides were involved in the gold bioreduction. Metallic gold was detected as microprecipitates on the biomass surface and in colloidal form as nanoparticles in the solution. Bioreduction with F. vesiculosus could be an alternative and environmentally friendly process that can be used for recovering gold from dilute hydrometallurgical solutions and leachates of electronic scraps, and for the synthesis of gold nanoparticles of different size and shape.

  9. Diffusion or advection? Mass transfer and complex boundary layer landscapes of the brown alga Fucus vesiculosus.

    PubMed

    Lichtenberg, Mads; Nørregaard, Rasmus Dyrmose; Kühl, Michael

    2017-03-01

    The role of hyaline hairs on the thallus of brown algae in the genus Fucus is long debated and several functions have been proposed. We used a novel motorized set-up for two-dimensional and three-dimensional mapping with O2 microsensors to investigate the spatial heterogeneity of the diffusive boundary layer (DBL) and O2 flux around single and multiple tufts of hyaline hairs on the thallus of Fucus vesiculosus. Flow was a major determinant of DBL thickness, where higher flow decreased DBL thickness and increased O2 flux between the algal thallus and the surrounding seawater. However, the topography of the DBL varied and did not directly follow the contour of the underlying thallus. Areas around single tufts of hyaline hairs exhibited a more complex mass-transfer boundary layer, showing both increased and decreased thickness when compared with areas over smooth thallus surfaces. Over thallus areas with several hyaline hair tufts, the overall effect was an apparent increase in the boundary layer thickness. We also found indications for advective O2 transport driven by pressure gradients or vortex shedding downstream from dense tufts of hyaline hairs that could alleviate local mass-transfer resistances. Mass-transfer dynamics around hyaline hair tufts are thus more complex than hitherto assumed and may have important implications for algal physiology and plant-microbe interactions.

  10. Cadmium tolerance and adsorption by the marine brown alga Fucus vesiculosus from the Irish Sea and the Bothnian Sea.

    PubMed

    Brinza, Loredana; Nygård, Charlotta A; Dring, Matthew J; Gavrilescu, Maria; Benning, Liane G

    2009-03-01

    Cadmium (Cd) uptake capacities and Cd tolerance of the marine alga Fucus vesiculosus from the Irish Sea (salinity 35 psu) and from the Bothnian Sea (northern Baltic, 5 psu) were quantified. These data were complemented by measurements of changes in maximal photosynthetic rate (P(max)), dark respiration rate and variable fluorescence vs. maximal fluorescence (F(v):F(m)). At concentrations between 0.01 and 1 mmol Cd l(-1), F. vesiculosus from the Bothnian Sea adsorbed significantly more (about 98%) Cd compared with F. vesiculosus from the Irish Sea. The photosynthetic measurements showed that the Bothnian Sea F. vesiculosus were more sensitive to Cd exposure than the Irish Sea algae. The algae from the Irish Sea showed negative photosynthetic effects only at 1 mmol Cd l(-1), which was expressed as a decreased P(max) (-12.3%) and F(v):F(m) (-4.6%). On the contrary, the algae from the Bothnian Sea were negatively affected already at Cd concentrations as low at 0.1 mmol Cd l(-1). They exhibited increased dark respiration (+11.1%) and decreased F(v):F(m) (-13.9%). The results show that F. vesiculosus from the Bothnian Sea may be an efficient sorption substrate for Cd removal from Cd contaminated seawater and this algae type may also have applications for wastewater treatment.

  11. Phlorotannins from brown algae (Fucus vesiculosus) inhibited the formation of advanced glycation endproducts by scavenging reactive carbonyls.

    PubMed

    Liu, Haiyan; Gu, Liwei

    2012-02-08

    Accumulation of advanced glycation end products (AGEs) in vivo is associated with aging, diabetes, Alzheimer's disease, renal failure, etc. The objective of this study was to investigate the inhibitory effects of brown algae Fucus vesiculosus phlorotannins on the formation of AGEs. F. vesiculosus phlorotannins were extracted using 70% acetone. The resultant extract was fractionated into dichloromethane, ethyl acetate, butanol, and water fractions. The ethyl acetate fraction was further fractionated into four subfractions (Ethyl-F1 to -F4) using a Sephadex LH-20 column. F. vesiculosus acetone extract or fractions significantly inhibited the formation of AGEs mediated by glucose and methylglyoxal in a concentration-dependent manner. The concentrations of F. vesiculosus extracts required to inhibit 50% of albumin glycation (EC(50)) in the bovine serum albumin (BSA)-methylglyoxal assay were lower than those of aminoguanidine (a drug candidate for diabetic complication), except for F. vesiculosus acetone extract and dichloromethane fraction. In the BSA-glucose assay, F. vesiculosus extracts inhibited BSA glycation more than or as effectively as aminoguanidine, except for Ethyl-F3 and -F4. The ethyl acetate fraction and its four subfractions scavenged more than 50% of methylglyoxal in two hours. The hypothesis whether F. vesiculosus phlorotannins scavenged reactive carbonyls by forming adducts was tested. Phloroglucinol, the constituent unit of phlorotannins, reacted with glyoxal and methylglyoxal. Five phloroglucinol-carbonyl adducts were detected and tentatively identified using HPLC-ESI-MS(n).

  12. Sex-biased gene expression in the brown alga Fucus vesiculosus

    PubMed Central

    2013-01-01

    Background The fucoid brown algae (Heterokontophyta, Phaeophyceae) are increasingly the focus of ecological genetics, biodiversity, biogeography and speciation research. The molecular genetics underlying mating system variation, where repeated dioecious – hermaphrodite switches during evolution are recognized, and the molecular evolution of sex-related genes are key questions currently hampered by a lack of genomic information. We therefore undertook a comparative analysis of male and female reproductive tissue transcriptomes against a vegetative background during natural reproductive cycles in Fucus vesiculosus. Results Over 300 k reads were assembled and annotated against public protein databases including a brown alga. Compared with the vegetative tissue, photosynthetic and carbohydrate metabolism pathways were under-expressed, particularly in male tissue, while several pathways involved in genetic information processing and replication were over-expressed. Estimates of sex-biased gene (SBG) expression were higher for male (14% of annotated orthologues) than female tissue (9%) relative to the vegetative background. Mean expression levels and variance were also greater in male- than female-biased genes. Major female-biased genes were carbohydrate-modifying enzymes with likely roles in zygote cell wall biogenesis and/or modification. Male-biased genes reflected distinct sperm development and function, and orthologues for signal perception (a phototropin), transduction (several kinases), and putatively flagella-localized proteins (including candidate gamete-recognition proteins) were uniquely expressed in males. Overall, the results suggest constraint on female-biased genes (possible pleiotropy), and less constrained male-biased genes, mostly associated with sperm-specific functions. Conclusions Our results support the growing contention that males possess a large array of genes regulating male fitness, broadly supporting findings in evolutionarily distant

  13. Arsenic binding to Fucus vesiculosus metallothionein.

    PubMed

    Merrifield, Maureen E; Ngu, Thanh; Stillman, Martin J

    2004-11-05

    The seaweed Fucus vesiculosus is a member of the brown algae family. Kille and co-workers [Biochem. J. 338 (1999) 553] reported that this species contains the gene for metallothionein. Metallothionein is a metalloprotein having low molecular weight, and high cysteine content, which binds a range of metals. F. vesiculosus bioaccumulates arsenic from the aquatic environment [Mar. Chem. 18 (1986) 321]. In this paper we describe arsenic binding to F. vesiculosus metallothionein, characterized by electrospray ionization mass spectrometry. Five arsenic-MT species were detected with increasing As to protein ratios. These results provide important information about the metal-chelation behaviour of this novel algal metallothionein which is a putative model for arsenic binding to F. vesiculosus in vivo.

  14. Antioxidant capacities of phlorotannins extracted from the brown algae Fucus vesiculosus.

    PubMed

    Wang, Tao; Jónsdóttir, Rósa; Liu, Haiyan; Gu, Liwei; Kristinsson, Hordur G; Raghavan, Sivakumar; Olafsdóttir, Gudrún

    2012-06-13

    A process for the effective extraction and fractionation of phlorotannins from Fucus vesiculosus with high antioxidant potentials was investigated. The antioxidant activity of F. vesiculosus extract/fractions was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, reducing power, and ferrous ion-chelating assays. Among the crude extract and different polarity fractions, the phlorotannin-enriched ethyl acetate fraction possessed the highest DPPH scavenging activity and reducing power. This fraction was further fractionated by Sephadex LH-20 column chromatography or ultrafiltration. The antioxidant properties were evaluated by both the above chemical antioxidant tests and a mononuclear cell-based bioassay. Sephadex subfractions LH-2 and LH-3 with high total phlorotannin content exhibited strong DPPH quenching activity, comparable to those of ascorbic acid and butylated hydroxytoluene and significantly higher than that of α-tocopherol. Polyphenols in F. vesiculosus were found to consist mainly of high molecular weight phlorotannin polymers. There were no clear relationships between the degree of polymerization, molecular size, and antioxidant activity. All the subfractions separated by Sephadex LH-20 column chromatography and ultrafiltration showed a high ability to scavenge reactive oxygen species generated by mononuclear cells. Further characterization of the phlorotannin compounds was performed on six Sephadex subfractions. Several phlorotannin oligomers were tentatively identified on the basis of HPLC-ESI-MS(n) analyses.

  15. High-performance liquid chromatographic analysis of phlorotannins from the brown alga Fucus vesiculosus.

    PubMed

    Koivikko, Riitta; Loponen, Jyrki; Pihlaja, Kalevi; Jormalainen, Veijo

    2007-01-01

    Separating individual compounds by HPLC represents an effective method for the detection and quantification of phenolic compounds and has been widely utilised. However, phlorotannins are commonly quantified using colorimetric methods, as the total amount of the whole compound group. In the present paper the separation of a set of individual soluble phlorotannins from the phenolic crude extract of Fucus vesiculosus was achieved by HPLC with UV photodiode array detection. Different gradient programs for reversed- and normal-phase HPLC methods were developed and tested. Normal-phase (NP) conditions with a silica stationary phase and a mobile phase with a linear gradient of increasing polarity were found to separate 16 individual components of the phenolic extract. The suitability of the NP-HPLC method for mass spectrometric application was preliminarily tested. Sample preparation was found to be a critical step in the analysis owing to the rapid oxidation of phlorotannins; ascorbic acid was used as an antioxidant.

  16. Seasonal variation in the antifouling defence of the temperate brown alga Fucus vesiculosus.

    PubMed

    Saha, Mahasweta; Wahl, Martin

    2013-01-01

    The important role of marine epibiotic biofilms in the interactions of the host with its environment has been acknowledged recently. Previous studies with the temperate brown macroalga Fucus vesiculosus have identified polar and non-polar compounds recovered from the algal surface that have the potential to control such biofilms. Furthermore, both the fouling pressure and the composition of the epibiotic bacterial communities on this macroalga varied seasonally. The extent to which this reflects a seasonal fluctuation of the fouling control mechanisms of the host is, however, unexplored in an ecological context. The present study investigated seasonal variation in the anti-settlement activity of surface extracts of F. vesiculosus against eight biofilm-forming bacteria isolated from rockweed-dominated habitats, including replication of two populations from two geographically distant sites. The anti-settlement activity at both sites was found to vary temporally, reaching a peak in summer/autumn. Anti-settlement activity also showed a consistent and strong difference between sites throughout the year. This study is the first to report temporal variation of antifouling defence originating from ecologically relevant surface-associated compounds.

  17. Epiphytic bacterial communities of the alga Fucus vesiculosus in oil-contaminated water areas of the Barents Sea.

    PubMed

    Pugovkin, D V; Liaimer, A; Jensen, J B

    2016-11-01

    Taxonomic compositions of epiphytic bacterial communities in water areas differing in levels of oil pollution were revealed. In total, 82 bacterial genera belonging to 16 classes and 11 phyla were detected. All detected representatives of epiphytic bacterial communities belonged to the phyla Actinobacteria, Bacteroidetes, Planctomycetes, Proteobacteria, Verrucomicrobia, Acidobacteria, Cyanobacteria, Firmicutes, and Fusobacteria and candidate division TM7. The ratio of the phyla in the communities varied depending on the levels of oil pollution. New data on taxonomic composition of uncultivated epiphytic bacterial communities of Fucus vesiculosus were obtained.

  18. Constitutive or Inducible Protective Mechanisms against UV-B Radiation in the Brown Alga Fucus vesiculosus? A Study of Gene Expression and Phlorotannin Content Responses.

    PubMed

    Creis, Emeline; Delage, Ludovic; Charton, Sophie; Goulitquer, Sophie; Leblanc, Catherine; Potin, Philippe; Ar Gall, Erwan

    2015-01-01

    A role as UV sunscreens has been suggested for phlorotannins, the phenolic compounds that accumulate in brown algae in response to a number of external stimuli and take part in cell wall structure. After exposure of the intertidal brown alga Fucus vesiculosus to artificial UV-B radiation, we examined its physiological responses by following the transcript level of the pksIII gene encoding a phloroglucinol synthase, likely to be involved in the first step of phlorotannins biosynthesis. We also monitored the expression of three targeted genes, encoding a heat shock protein (hsp70), which is involved in global stress responses, an aryl sulfotransferase (ast), which could be involved in the sulfation of phlorotannins, and a vanadium bromoperoxidase (vbpo), which can potentially participate in the scavenging of Reactive Oxygen Species (ROS) and in the cross-linking and condensation of phlorotannins. We investigated whether transcriptional regulation of these genes is correlated with an induction of phlorotannin accumulation by establishing metabolite profiling of purified fractions of low molecular weight phlorotannins. Our findings demonstrated that a high dose of UV-B radiation induced a significant overexpression of hsp70 after 12 and 24 hours following the exposure to the UV-B treatment, compared to control treatment. The physiological performance of algae quantified by the photosynthetic efficiency (Fv/Fm) was slightly reduced. However UV-B treatment did not induce the accumulation of soluble phlorotannins in F. vesiculosus during the kinetics of four weeks, a result that may be related to the lack of induction of the pksIII gene expression. Taken together these results suggest a constitutive accumulation of phlorotannins occurring during the development of F.vesiculosus, rather than inducible processes. Gene expression studies and phlorotannin profiling provide here complementary approaches to global quantifications currently used in studies of phenolic compounds

  19. Analysis of bioactive ingredients in the brown alga Fucus vesiculosus by capillary electrophoresis and neutron activation analysis.

    PubMed

    Truus, Kalle; Vaher, Merike; Koel, Mihkel; Mähar, Andres; Taure, Imants

    2004-07-01

    Two different types of bioactive components of the seaweed Fucus vesiculosus were analysed: (1) polyphenols (phlorotannins) by capillary electrophoresis (CE) and (2) mineral part (including bioactive microelements) by neutron activation analysis (NAA). CE experiments were carried out using a UV detector (at 210 nm) and an uncoated silica capillary. The best separation was achieved at a voltage of 20 kV using borate or acetate buffer in a methanol/acetonitrile mixture as background electrolyte. The CE analysis data were confirmed by high-performance liquid chromatography (HPLC). Determination of mineral composition of algal biomass by NAA was performed on the basis of various nuclides; the best results (from 38 elements determined) were obtained for Mn, Fe, Zn, As, Br, Sr, I, Ba, Au and Hg.

  20. Induction of expression of a 14-3-3 gene in response to copper exposure in the marine alga, Fucus vesiculosus.

    PubMed

    Owen, Jennifer R; Morris, Ceri A; Nicolaus, Beate; Harwood, John L; Kille, Peter

    2012-01-01

    The macro-alga Fucus vesiculosus has a broad global and estuarine distribution and exhibits exceptional resistance to toxic metals, the molecular basis of which is poorly understood. To address this issue a cDNA library was constructed from an environmental isolate of F. vesiculosus growing in an area with chronic copper pollution. Characterisation of this library led to the identification of a cDNA encoding a protein known to be synthesised in response to toxicity, a full length 14-3-3 exhibiting a 71% identity to human/mouse epsilon isoform, 70-71% identity to yeast BMH1/2 and 95 and 71% identity to the Ectocarpus siliculosus 14-3-3 isoforms 1 and 2 respectively. Preliminary characterisation of the expression profile of the 14-3-3 indicated concentration- and time-dependent inductions on acute exposure of F. vesiculosus of copper (3-30 μg/l). Higher concentrations of copper (≥150 μg/l) did not elicit significant induction of the 14-3-3 gene compared with the control even though levels of both intracellular copper and the expression of a cytosolic metal chaperone, metallothionein, continued to rise. Analysis of gene expression within environmental isolates demonstrated up-regulation of the 14-3-3 gene associated with the known copper pollution gradient. Here we report for the first time, identification of a gene encoding a putative 14-3-3 protein in a multicellular alga and provide preliminary evidence to link the induction of this 14-3-3 gene to copper exposure in this alga. Interestingly, the threshold exposure profile may be associated with a decrease in the organism's ability to control copper influx so that it perceives copper as a toxic response.

  1. Isolated thallus-associated compounds from the macroalga Fucus vesiculosus mediate bacterial surface colonization in the field similar to that on the natural alga.

    PubMed

    Lachnit, Tim; Wahl, Martin; Harder, Tilmann

    2010-01-01

    This study investigated whether surface-associated compounds isolated from the macroalga Fucus vesiculosus had the potential to mediate microbial and/or macrobial epibiosis similar to that on the natural alga. To selectively yield thallus-associated compounds and avoid contamination by intracellular algal compounds, cell lysis was monitored by surface microscopy of algal cells and chemical profiling of algal surface extracts by coupled gas chromatography mass spectroscopy. The optimized extraction resulted in polar and non-polar algal surface extracts. The non-polar surface extract was immobilized in hydrogel, the polar surface extract was homogeneously perfused through the gel to ensure a temporally constant delivery of polar extract components. During a 7 day field trial, bacterial biofilms were formed on control gels and gels featuring polar and/or non-polar extract components. PERMANOVA revealed that bacterial community profiles on controls and on gels featuring polar or non-polar extract were significantly different from the profile on F. vesiculosus, while the profile on the gels bearing both polar and non-polar extracts was not. Moreover, the polar surface extracts inhibited the settlement of barnacle cyprids. Considering the pronounced effects of bacterial biofilms on invertebrate larval settlement, these results suggest that algal surface chemistry affects macrofouling not only directly but also indirectly, via its control of biofilm formation and composition.

  2. Future warming and acidification effects on anti-fouling and anti-herbivory traits of the brown alga Fucus vesiculosus (Phaeophyceae).

    PubMed

    Raddatz, Stefanie; Guy-Haim, Tamar; Rilov, Gil; Wahl, Martin

    2017-02-01

    Human-induced ocean warming and acidification have received increasing attention over the past decade and are considered to have substantial consequences for a broad range of marine species and their interactions. Understanding how these interactions shift in response to climate change is particularly important with regard to foundation species, such as the brown alga Fucus vesiculosus. This macroalga represents the dominant habitat former on coastal rocky substrata of the Baltic Sea, fulfilling functions essential for the entire benthic community. Its ability to withstand extensive fouling and herbivory regulates the associated community and ecosystem dynamics. This study tested the interactive effects of future warming, acidification, and seasonality on the interactions of a marine macroalga with potential foulers and consumers. F. vesiculosus rockweeds were exposed to different combinations of conditions predicted regionally for the year 2100 (+∆5°C, +∆700 μatm CO2 ) using multifactorial long-term experiments in novel outdoor benthic mesocosms ("Benthocosms") over 9-12-week periods in four seasons. Possible shifts in the macroalgal susceptibility to fouling and consumption were tested using consecutive bioassays. Algal susceptibility to fouling and grazing varied substantially among seasons and between treatments. In all seasons, warming predominantly affected anti-fouling and anti-herbivory interactions while acidification had a subtle nonsignificant influence. Interestingly, anti-microfouling activity was highest during winter under warming, while anti-macrofouling and anti-herbivory activities were highest in the summer under warming. These contrasting findings indicate that seasonal changes in anti-fouling and anti-herbivory traits may interact with ocean warming in altering F. vesiculosus community composition in the future.

  3. Contents of soluble, cell-wall-bound and exuded phlorotannins in the brown alga Fucus vesiculosus, with implications on their ecological functions.

    PubMed

    Koivikko, Riitta; Loponen, Jyrki; Honkanen, Tuija; Jormalainen, Veijo

    2005-01-01

    Phlorotannins are ubiquitous secondary metabolites in brown algae that are phenotypically plastic and suggested to have multiple ecological roles. Traditionally, phlorotannins have been quantified as total soluble phlorotannins. Here, we modify a quantification procedure to measure, for the first time, the amount of cell-wall-bound phlorotannins. We also optimize the quantification of soluble phlorotannins. We use these methods to study the responses of soluble and cell-wall-bound phlorotannin to nutrient enrichment in growing and nongrowing parts of the brown alga Fucus vesiculosus. We also examine the effects of nutrient shortage and herbivory on the rate of phlorotannin exudation. Concentrations of cell-wall-bound phlorotannins were much lower than concentrations of soluble phlorotannins; we also found that nutrient treatment over a period of 41 days affected only soluble phlorotannins. Concentrations of each phlorotannin type correlated positively between growing and nongrowing parts of individual seaweeds. However, within nongrowing thalli, soluble and cell-wall-bound phlorotannins were negatively correlated, whereas within growing thalli there was no correlation. Phlorotannins were exuded from the thallus in all treatments. Herbivory increased exudation, while a lack of nutrients had no effect on exudation. Because the amount of cell-wall-bound phlorotannins is much smaller than the amount of soluble phlorotannins, the major function of phlorotannins appears to be a secondary one.

  4. In vitro chemopreventive potential of fucophlorethols from the brown alga Fucus vesiculosus L. by anti-oxidant activity and inhibition of selected cytochrome P450 enzymes.

    PubMed

    Parys, Sabine; Kehraus, Stefan; Krick, Anja; Glombitza, Karl-Werner; Carmeli, Shmuel; Klimo, Karin; Gerhäuser, Clarissa; König, Gabriele M

    2010-02-01

    Within a project focusing on the chemopreventive potential of algal phenols, two phloroglucinol derivatives, belonging to the class of fucophlorethols, and the known fucotriphlorethol A were obtained from the ethanolic extract of the brown alga Fucus vesiculosus L. The compounds trifucodiphlorethol A and trifucotriphlorethol A are composed of six and seven units of phloroglucinol, respectively. The compounds were examined for their cancer chemopreventive potential, in comparison with the monomer phloroglucinol. Trifucodiphlorethol A, trifucotriphlorethol A as well as fucotriphlorethol A were identified as strong radical scavengers, with IC(50) values for scavenging of 1,1-diphenyl-2 picrylhydrazyl radicals (DPPH) in the range of 10.0-14.4 microg/ml. All three compounds potently scavenged peroxyl radicals in the oxygen radical absorbance capacity (ORAC) assay. In addition, the compounds were shown to inhibit cytochrome P450 1A activity with IC(50) values in the range of 17.9-33 microg/ml, and aromatase (Cyp19) activity with IC(50) values in the range of 1.2-5.6 microg/ml.

  5. Travelling in time with networks: Revealing present day hybridization versus ancestral polymorphism between two species of brown algae, Fucus vesiculosus and F. spiralis

    PubMed Central

    2011-01-01

    Background Hybridization or divergence between sympatric sister species provides a natural laboratory to study speciation processes. The shared polymorphism in sister species may either be ancestral or derive from hybridization, and the accuracy of analytic methods used thus far to derive convincing evidence for the occurrence of present day hybridization is largely debated. Results Here we propose the application of network analysis to test for the occurrence of present day hybridization between the two species of brown algae Fucus spiralis and F. vesiculosus. Individual-centered networks were analyzed on the basis of microsatellite genotypes from North Africa to the Pacific American coast, through the North Atlantic. Two genetic distances integrating different time steps were used, the Rozenfeld (RD; based on alleles divergence) and the Shared Allele (SAD; based on alleles identity) distances. A diagnostic level of genotype divergence and clustering of individuals from each species was obtained through RD while screening for exchanges through putative hybridization was facilitated using SAD. Intermediate individuals linking both clusters on the RD network were those sampled at the limits of the sympatric zone in Northwest Iberia. Conclusion These results suggesting rare hybridization were confirmed by simulation of hybrids and F2 with directed backcrosses. Comparison with the Bayesian method STRUCTURE confirmed the usefulness of both approaches and emphasized the reliability of network analysis to unravel and study hybridization PMID:21281515

  6. Dietary fiber and antioxidant capacity in Fucus vesiculosus products.

    PubMed

    Díaz-Rubio, M Elena; Pérez-Jiménez, Jara; Saura-Calixto, Fulgencio

    2009-01-01

    Several nutraceutical products have been developed from Fucus vesiculosus, a brown edible seaweed, rich in dietary fiber and polyphenolic antioxidants (phlorotannins). The aim of this work was to compare the antioxidant capacity and polysaccharide composition of raw Fucus with those of some common commercial nutraceuticals. All tested products contained a high percentage of dietary fiber (45-59%), raw Fucus powder being the sample with the highest content. Also, raw Fucus powder exhibited significantly higher antioxidant capacity (determined by FRAP, ABTS and ORAC assays) than the commercial fucoidans and commercial antioxidant extracts. Polyphenols (phlorotannins) seem to be the main contributors to Fucus' antioxidant capacity in both raw powder and commercial fucoidans.

  7. Photosynthetic activity in marine and brackish water strains of Fucus vesiculosus and Fucus radicans (Phaeophyceae) at different light qualities.

    PubMed

    Svahn, Carina; Maria Gylle, A; Ekelund, Nils G A

    2012-01-01

    This study investigates the effects of different light qualities on the photosynthetic capacity of the brown algae Fucus vesiculosus, from the Norwegian Sea, and Fucus radicans and F. vesiculosus, from the Bothnian Sea. The electron transport rates (ETR) obtained for F. vesiculosus from the Norwegian Sea showed significantly higher levels of light saturation compared with both species of algae from the Bothnian Sea. The maximum of ETR values for the Norwegian Sea strain showed no significant changes due to varying light quality compared with the initial values. For F. vesiculosus, from the Bothnian Sea, treatment with blue light showed an effect after 1 week of 30 and 90 μmol photons m(-2) s(-1) (P<0.01), and for F. radicans from the Bothnian Sea, at the irradiance of 90 μmol photons m(-2) s(-1) and 1 week (P<0.01). After 1 week in the Bothnian Sea species and after 2 weeks in F. vesiculosus from the Norwegian Sea, the photosynthetic efficiency (α) was significantly higher regardless of light quality and irradiance compared with the initial values. Variation in light quality and irradiance had minor effects on the F(v):F(m) values of the three algal strains studied.

  8. Seasonal fluctuations in chemical defenses against macrofouling in Fucus vesiculosus and Fucus serratus from the Baltic Sea.

    PubMed

    Rickert, Esther; Karsten, Ulf; Pohnert, Georg; Wahl, Martin

    2015-01-01

    Macroalgae, especially perennial species, are exposed to a seasonally variable fouling pressure. It was hypothesized that macroalgae regulate their antifouling defense to fouling pressure. Over one year, the macrofouling pressure and the chemical anti-macrofouling defense strength of the brown algae Fucus vesiculosus and Fucus serratus were assessed with monthly evaluation. The anti-macrofouling defense was assessed by means of surface-extracted Fucus metabolites tested at near-natural concentrations in a novel in situ bioassay. Additionally, the mannitol content of both Fucus species was determined to assess resource availability for defense production. The surface chemistry of both Fucus species exhibited seasonal variability in attractiveness to Amphibalanus improvisus and Mytilus edulis. Of this variability, 50-60% is explained by a sinusoidal model. Only F. vesiculosus extracts originating from the spring and summer significantly deterred settlement of A. improvisus. The strength of macroalgal antifouling defense did not correlate either with in situ macrofouling pressure or with measured mannitol content, which, however, were never depleted.

  9. Biosorption of cadmium, lead and copper with calcium alginate xerogels and immobilized Fucus vesiculosus.

    PubMed

    Mata, Y N; Blázquez, M L; Ballester, A; González, F; Muñoz, J A

    2009-04-30

    This paper determines the effect of immobilized brown alga Fucus vesiculosus in the biosorption of heavy metals with alginate xerogels. Immobilization increased the kinetic uptakes and intraparticle diffusion rates of the three metals. The Langmuir maximum biosorption capacity increased twofold for cadmium, 10 times for lead, and decreased by half for copper. According to this model, the affinity of the metals for the biomass was as follows: Cu>Pb>Cd without alga and Pb>Cu>Cd with alga. FITR confirmed that carboxyl groups were the main groups involved in the metal uptake. Calcium in the gels was displaced by heavy metals from solution according to the "egg-box" model. The restructured gel matrix became more uniform and organized as shown by scanning electron microscopy (SEM) characterization. F. vesiculosus immobilized in alginate xerogels constitutes an excellent biosorbent for cadmium, lead and copper, sometimes surpassing the biosorption performance of alginate alone and even the free alga.

  10. FLUORESCENCE EMISSION SPECTRA OF MARINE AND BRACKISH-WATER ECOTYPES OF FUCUS VESICULOSUS AND FUCUS RADICANS (PHAEOPHYCEAE) REVEAL DIFFERENCES IN LIGHT-HARVESTING APPARATUS(1).

    PubMed

    Maria Gylle, Anna; Rantamäki, Susanne; Ekelund, Nils G A; Tyystjärvi, Esa

    2011-02-01

    The Bothnian Sea in the northerly part of the Baltic Sea is a geologically recent brackish-water environment, and rapid speciation is occurring in the algal community of the Bothnian Sea. We measured low-temperature fluorescence emission spectra from the Bothnian Sea and the Norwegian Sea ecotypes of Fucus vesiculosus L., a marine macroalga widespread in the Bothnian Sea. Powdered, frozen thallus was used to obtain undistorted emission spectra. The spectra were compared with spectra measured from the newly identified species Fucus radicans Bergström et L. Kautsky, which is a close relative of F. vesiculosus and endemic to the Bothnian Sea. The spectrum of variable fluorescence was used to identify fluorescence peaks originating in PSI and PSII in this chl c-containing alga. The spectra revealed much higher PSII emission, compared to PSI emission, in the Bothnian Sea ecotype of F. vesiculosus than in F. radicans or in the Norwegian Sea ecotype of F. vesiculosus. The results suggest that more light-harvesting chl a/c proteins serve PSII in the Bothnian Sea ecotype of F. vesiculosus than in the two other algal strains. Treatment of the Bothnian Sea ecotype of F. vesiculosus in high salinity (10, 20, and 35 practical salinity units) for 1 week did not lead to spectral changes, indicating that the measured features of the Bothnian Sea F. vesiculosus are stable and not simply a direct result of exposure to low salinity.

  11. Intriguing asexual life in marginal populations of the brown seaweed Fucus vesiculosus.

    PubMed

    Tatarenkov, A; Bergström, L; Jönsson, R B; Serrão, E A; Kautsky, L; Johannesson, K

    2005-02-01

    Reproduction of attached large brown algae is known to occur only by sexual zygotes. Using microsatellites we show evolution of asexual reproduction in the bladder wrack promoting population persistence in the brackish water Baltic Sea (< 6 psu). Here a dwarf morph of Fucus vesiculosus is dominated by a single clone but clonal reproduction is also present in the common form of the species. We describe a possible mechanism for vegetative reproduction of attached algae, and conclude that clonality plays an important role in persistence and dispersal of these marginal populations, in which sexual reproduction is impaired by low salinity.

  12. Surface-associated fucoxanthin mediates settlement of bacterial epiphytes on the rockweed Fucus vesiculosus.

    PubMed

    Saha, M; Rempt, M; Grosser, K; Pohnert, G; Weinberger, F

    2011-04-01

    The chemical defence against microfouling in the brown seaweed Fucus vesiculosus was investigated and an inhibitor of bacterial settlement was isolated by bioassay-guided fractionation of non-polar surface extracts. UV-vis and mass spectrometry were used to identify the compound as the carotenoid fucoxanthin. The metabolite was tested at the natural concentration (in a surface volume based assay) against the settlement of four bacterial strains isolated from F. vesiculosus and 11 strains isolated from co-occurring algae and marine sediment. Surface concentrations between 1.4 and 6 μg cm(-2) resulted in 50% inhibition of four of these isolates, which were studied in more detail using a surface area-based assay, while a fifth isolate proved to be less sensitive. The presence of fucoxanthin on the surface of F. vesiculosus was demonstrated with two different surface extraction methods. Fucoxanthin was detected at concentrations between 0.7 and 9 μg cm(-2) on the algal surface. Fucoxanthin was still present at the algal surface after removal of associated diatoms through mechanical cleaning and germanium dioxide treatment and was thus mainly produced by F. vesiculosus rather than by diatoms. Thus, the photosynthetic pigment fucoxanthin appears to be ecologically relevant as a surface-associated antimicrobial agent, acting against the settlement of bacteria on the surface of the macroalga F. vesiculosus.

  13. Highly selective and rapid arsenic removal by metabolically engineered Escherichia coli cells expressing Fucus vesiculosus metallothionein.

    PubMed

    Singh, Shailendra; Mulchandani, Ashok; Chen, Wilfred

    2008-05-01

    An arsenic-chelating metallothionein (fMT) from the arsenic-tolerant marine alga Fucus vesiculosus was expressed in Escherichia coli, resulting in 30- and 26-fold-higher As(III) and As(V) binding, respectively. Coexpression of the As(III)-specific transporter GlpF with fMT further improved arsenic accumulation and offered high selectivity toward As. Resting E. coli cells coexpressing fMT and GlpF completely removed trace amounts (35 ppb) of As(III) within 20 min, providing a promising technology for compliance with the As limit of 10 ppb newly recommended by the U.S. EPA.

  14. [Role of auxin in induction of polarity in zygotes of Fucus vesiculosus L].

    PubMed

    Polevoĭ, V V; Tarakhovskaia, E R; Maslov, Iu I; Polevoĭ, A V

    2003-01-01

    We studied the effects of auxin (indolyl-3 acetic acid) on formation of the primary polarity axis in zygotes of the brown algae Fucus vesiculosus. Within the first 2.5 h after fertilization, the zygotes release this phytohormone in the environment. The treatment of developing zygotes with the inhibitor of indolyl-3-acetic acid transport from the cell triiodobenzoic acid at 5 mg/l arrests the auxin secretion and leads to its accumulation in the cells. This causes a significant delay in zygote polarization. The treatment of zygotes with the exogenous indolyl-3-acetic acid at 1 mg/l stimulates cell polarization and formation of a rhizoid process. When auxin was added to the medium with triiodobenzoic acid, the inhibitory effect of the latter was fully relieved. It has been proposed that the content of indolyl-3-acetic acid in the environment is a key factor in the induction of polarity of the F. vesiculosus zygotes.

  15. Seasonal Variations in Surface Metabolite Composition of Fucus vesiculosus and Fucus serratus from the Baltic Sea

    PubMed Central

    Rickert, Esther; Wahl, Martin; Link, Heike; Richter, Hannes; Pohnert, Georg

    2016-01-01

    Perennial macroalgae within the genus Fucus are known to exude metabolites through their outer thallus surface. Some of these metabolites have pro- and/or antifouling properties. Seasonal fluctuations of natural fouling pressure and chemical fouling control strength against micro- and macrofoulers have previously been observed in Fucus, suggesting that control strength varies with threat. To date, a study on the seasonal composition of surface associated metabolites, responsible for much of the fouling control, has not been done. We sampled individuals of the two co-occurring species F. vesiculosus and F. serratus at monthly intervals (six per species and month) during a one-year field study. We analysed the chemical composition of surface associated metabolites of both Fucus species by means of gas chromatography-mass spectrometry (GC-MS) to describe temporal patterns in chemical surface composition. Additionally, we correlated abiotic and biotic parameters recorded monthly within the sampled habitat with the variation in the chemical surface landscape of Fucus. Our study revealed that the chemical surface composition of both Fucus species exhibits substantial seasonal differences between spring/summer and autumn/winter months. Light and temperature explained most of the seasonal variability in surface metabolite composition of both Fucus species. A strong summerly up-regulation of eighteen saccharides and two hydroxy acids in F. vesiculosus as well as of four fatty acids and two saccharides in F. serratus was observed. We discuss how these up-regulated molecules may have a complex effect on associated microfoulers, both promoting or decreasing fouling depending on metabolite and bacterial identity. These seasonal shifts in the surface metabolome seem to exert a compound control of density and composition of the Fucus associated biofilm. PMID:27959901

  16. Seasonal Variations in Surface Metabolite Composition of Fucus vesiculosus and Fucus serratus from the Baltic Sea.

    PubMed

    Rickert, Esther; Wahl, Martin; Link, Heike; Richter, Hannes; Pohnert, Georg

    2016-01-01

    Perennial macroalgae within the genus Fucus are known to exude metabolites through their outer thallus surface. Some of these metabolites have pro- and/or antifouling properties. Seasonal fluctuations of natural fouling pressure and chemical fouling control strength against micro- and macrofoulers have previously been observed in Fucus, suggesting that control strength varies with threat. To date, a study on the seasonal composition of surface associated metabolites, responsible for much of the fouling control, has not been done. We sampled individuals of the two co-occurring species F. vesiculosus and F. serratus at monthly intervals (six per species and month) during a one-year field study. We analysed the chemical composition of surface associated metabolites of both Fucus species by means of gas chromatography-mass spectrometry (GC-MS) to describe temporal patterns in chemical surface composition. Additionally, we correlated abiotic and biotic parameters recorded monthly within the sampled habitat with the variation in the chemical surface landscape of Fucus. Our study revealed that the chemical surface composition of both Fucus species exhibits substantial seasonal differences between spring/summer and autumn/winter months. Light and temperature explained most of the seasonal variability in surface metabolite composition of both Fucus species. A strong summerly up-regulation of eighteen saccharides and two hydroxy acids in F. vesiculosus as well as of four fatty acids and two saccharides in F. serratus was observed. We discuss how these up-regulated molecules may have a complex effect on associated microfoulers, both promoting or decreasing fouling depending on metabolite and bacterial identity. These seasonal shifts in the surface metabolome seem to exert a compound control of density and composition of the Fucus associated biofilm.

  17. Effects of Fucus vesiculosus covering intertidal mussel beds in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Albrecht, A.; Reise, K.

    1994-06-01

    The brown alga Fucus vesiculosus forma mytili (Nienburg) Nienhuis covered about 70% of mussel bed ( Mytilus edulis) surface area in the lower intertidal zone of Königshafen, a sheltered sandy bay near the island of Sylt in the North Sea. Mean biomass in dense patches was 584 g ash-free dry weight m-2 in summer. On experimental mussel beds, fucoid cover enhanced mud accumulation and decreased mussel density. The position of mussels underneath algal canopy was mainly endobenthic (87% of mussels with >1/3 of shell sunk into mud). In the absence of fucoids, mussels generated epibenthic garlands (81% of mussels with <1/3 of shell buried in mud). Mussel density underneath fucoid cover was 40 to 73% of mussel density without algae. On natural beds, barnacles (Balanidae), periwinkles ( Littorina littorea) and crabs (particularly juveniles of Carcinus maenas) were significantly less abundant in the presence of fucoids, presumably because most of the mussels were covered with sediment, whereas in the absence of fucoids, epibenthic mussel clumps provided substratum as well as interstitial hiding places. The endobenthic macrofauna showed little difference between covered and uncovered mussel beds. On the other hand, grazing herbivores — the flat periwinkle Littorina mariae, the isopod Jaera albifrons and the amphipods Gammarus spp. — were more abundant at equivalent sites with fucoid cover. The patchy growth of Fucus vesiculosus on mussel beds in the intertidal Wadden Sea affects mussels and their epibionts negatively, but supports various herbivores and increases overall benthic diversity.

  18. Rhenium uptake and distribution in phaeophyceae macroalgae, Fucus vesiculosus

    PubMed Central

    Racionero-Gómez, B.; Sproson, A. D.; Selby, D.; Gröcke, D. R.; Redden, H.; Greenwell, H. C.

    2016-01-01

    Owing to Rhenium (Re) having no known biological role, it is not fully understood how Re is concentrated in oil kerogens. A commonly held assumption is that Re is incorporated into decomposing biomass under reducing conditions. However, living macroalgae also concentrate Re to several orders of magnitude greater than that of seawater. This study uses Fucus vesiculosus to assess Re uptake and its subsequent localization in the biomass. It is demonstrated that the Re abundance varies within the macroalgae and that Re is not located in one specific structure. In F. vesiculosus, the uptake and tolerance of Re was evaluated via tip cultures grown in seawater of different Re(VII) compound concentrations (0–7450 ng g−1). A positive correlation is shown between the concentration of Re-doped seawater and the abundance of Re accumulated in the tips. However, significant differences between Re(VII) compounds are observed. Although the specific cell structures where the Re is localized is not known, our findings suggest that Re is not held within chloroplasts or cytoplasmic proteins. In addition, metabolically inactivated F. vesiculosus does not accumulate Re, which indicates that Re uptake is via syn-life bioadsorption/bioaccumulation and that macroalgae may provide a source for Re phytomining and/or bioremediation. PMID:27293798

  19. Rhenium uptake and distribution in phaeophyceae macroalgae, Fucus vesiculosus.

    PubMed

    Racionero-Gómez, B; Sproson, A D; Selby, D; Gröcke, D R; Redden, H; Greenwell, H C

    2016-05-01

    Owing to Rhenium (Re) having no known biological role, it is not fully understood how Re is concentrated in oil kerogens. A commonly held assumption is that Re is incorporated into decomposing biomass under reducing conditions. However, living macroalgae also concentrate Re to several orders of magnitude greater than that of seawater. This study uses Fucus vesiculosus to assess Re uptake and its subsequent localization in the biomass. It is demonstrated that the Re abundance varies within the macroalgae and that Re is not located in one specific structure. In F. vesiculosus, the uptake and tolerance of Re was evaluated via tip cultures grown in seawater of different Re(VII) compound concentrations (0-7450 ng g(-1)). A positive correlation is shown between the concentration of Re-doped seawater and the abundance of Re accumulated in the tips. However, significant differences between Re(VII) compounds are observed. Although the specific cell structures where the Re is localized is not known, our findings suggest that Re is not held within chloroplasts or cytoplasmic proteins. In addition, metabolically inactivated F. vesiculosus does not accumulate Re, which indicates that Re uptake is via syn-life bioadsorption/bioaccumulation and that macroalgae may provide a source for Re phytomining and/or bioremediation.

  20. Alpha-amylase and alpha-glucosidase inhibition is differentially modulated by fucoidan obtained from Fucus vesiculosus and Ascophyllum nodosum.

    PubMed

    Kim, Kyung-Tae; Rioux, Laurie-Eve; Turgeon, Sylvie L

    2014-02-01

    Fucoidan is a water-soluble, negatively charged, biologically active polysaccharide found in great abundance in brown marine algae. However, the inhibition of α-amylase and α-glucosidase by fucoidan derived from two algal species (Ascophyllum nodosum and Fucus vesiculosus) harvested at different periods (accounting for seasonal and yearly variations) has never been investigated. It was found that fucoidans inhibited α-glucosidase differently, depending on the algal species from which it was extracted and the algae's season of harvest. Fucoidan extracted from A. nodosum was a more potent inhibitor of α-glucosidase, with an IC50 ranging from 0.013 to 0.047 mg/mL, than the inhibition by fucoidan extracted from F. vesiculosus (IC50=0.049 mg/mL). In contrast, fucoidan extracted from F. vesiculosus did not inhibit α-amylase activity, while fucoidan from A. nodosum decreased α-amylase activity by 7-100% at 5 mg/mL depending upon the algae harvest period. An IC50 of 0.12-4.64 mg/mL for fucoidan from A. nodosum was found for the α-amylase inhibition. The ability of fucoidan to inhibit α-amylase and α-glucosidase thus varies according to the algae species and harvest period. A. nodosum is more suitable than F. vesiculosus as a source of fucoidan to inhibit α-amylase and α-glucosidase activities. Their potential benefits towards Type 2 diabetes management should be further investigated.

  1. Variation of phlorotannins among three populations of Fucus vesiculosus as revealed by HPLC and colorimetric quantification.

    PubMed

    Koivikko, R; Eränen, J K; Loponen, J; Jormalainen, V

    2008-01-01

    In ecological studies, phlorotannins have conventionally been quantified as a group with similar functionality. Since this group consists of oligo- and polymers, the quantification of their pooled contents alone may not sufficiently describe the variation of these metabolites. Genetic variation, plastic responses to environment, and the ecological functions of separate phlorotannin oligo- and polymers may differ. Two analyses, i.e., the colorimetric Folin-Ciocalteu assay and a normal-phase high-performance liquid chromatographic (HPLC) method were used to study genetic and environmental variation in phlorotannins of the brown alga Fucus vesiculosus (L.). The colorimetric method provides the total phlorotannin content, the latter a profile of 14 separate traces from the phenolic extract that represent an individual or groups of phlorotannins. We reared the algae that originated from three separate populations in a common garden for 3 months under ambient and enriched-nutrient availability and found that they differed in both their total phlorotannin content and in phlorotannin profiles. Some individual traces of the profiles separated the populations more clearly than the colorimetric assay. Although nutrient enrichment decreased total phlorotannin content, it did not show a significant influence on the phlorotannin profile. This implies that plastic responses of compounds other than phlorotannins may interfere with the determination of total phlorotannins. However, the phlorotannin profile and the total content showed genetic variation among local populations of F. vesiculosus; therefore, phlorotannins may respond to natural selection and evolve both quantitatively and qualitatively.

  2. FREQUENT CLONALITY IN FUCOIDS (FUCUS RADICANS AND FUCUS VESICULOSUS; FUCALES, PHAEOPHYCEAE) IN THE BALTIC SEA(1).

    PubMed

    Johannesson, Kerstin; Johansson, Daniel; Larsson, Karl H; Huenchuñir, Cecilia J; Perus, Jens; Forslund, Helena; Kautsky, Lena; Pereyra, Ricardo T

    2011-10-01

    Asexual reproduction by cloning may affect the genetic structure of populations, their potential to evolve, and, among foundation species, contributions to ecosystem functions. Macroalgae of the genus Fucus are known to produce attached plants only by sexual recruitment. Recently, however, clones of attached plants recruited by asexual reproduction were observed in a few populations of Fucus radicans Bergström et L. Kautsky and F. vesiculosus L. inside the Baltic Sea. Herein we assess the distribution and prevalence of clonality in Baltic fucoids using nine polymorphic microsatellite loci and samples of F. radicans and F. vesiculosus from 13 Baltic sites. Clonality was more common in F. radicans than in F. vesiculosus, and in both species it tended to be most common in northern Baltic sites, although variation among close populations was sometimes extensive. Individual clonal lineages were mostly restricted to single or nearby locations, but one clonal lineage of F. radicans dominated five of 10 populations and was widely distributed over 550 × 100 km of coast. Populations dominated by a few clonal lineages were common in F. radicans, and these were less genetically variable than in other populations. As thalli recruited by cloning produced gametes, a possible explanation for this reduced genetic variation is that dominance of one or a few clonal lineages biases the gamete pool resulting in a decreased effective population size and thereby loss of genetic variation by genetic drift. Baltic fucoids are important habitat-forming species, and genetic structure and presence of clonality have implications for conservation strategies.

  3. Macroinvertebrates communities associated with the decomposition of Phragmites australis and Fucus vesiculosus in transitional systems

    NASA Astrophysics Data System (ADS)

    Lopes, Marta Lobão; Martins, Patrícia; Rodrigues, Ana Maria; Quintino, Victor

    2013-10-01

    The decomposition rates of a macrophyte (Phragmites australis) and an alga (Fucus vesiculosus) and the associated macrofauna communities were studied along a full salinity gradient, using the leaf-bag technique and four sampling times (days 3, 7, 15 and 30). A control was set up using an artificial substrate. A subsequent study conducted in the mesohaline part of the salinity gradient also included empty bags as procedure control. The decay rates of the alga and the macrophyte were significantly different, the alga decaying faster, and presented an opposite trend along the salinity gradient, with the faster decay rate for reed in the less saline areas and for the alga in the euhaline part of the gradient. The fauna associated with the decaying and the artificial substrate showed equally well the benthic succession from the marine to the freshwater areas, in all sampling times. Arthropods were dominant in all substrates along the estuarine gradient and replaced by annelids in freshwater. No significant differences were found between the benthic communities associated with P. australis and F. vesiculosus, despite the strong differences in the decay rates, suggesting that these do not seem to be primarily related to the benthic colonizers. Although the organic substrates sustained a more abundant fauna, the benthic communities did not show significant differences between the organic and the artificial substrates, especially at the level of the species composition, suggesting that the macroinvertebrates may colonize both substrates to feed on the biofilm and/or to seek shelter. The strongly impoverished benthic community sampled by the empty bags reinforced this idea.

  4. Compounds associated with algal surfaces mediate epiphytic colonization of the marine macroalga Fucus vesiculosus.

    PubMed

    Lachnit, Tim; Fischer, Matthias; Künzel, Sven; Baines, John F; Harder, Tilmann

    2013-05-01

    The macroalga Fucus vesiculosus carries a specific community of surface bacteria. To identify chemical compounds that possibly mediate abundance and community composition of algae-associated bacteria, we tested the effect of surface-available algal compounds on bacterial settlement and community composition under field conditions. Compounds on algal thalli were separated from the surface by extraction with organic solvents and investigated on growth inhibition and settlement of bacterial isolates. Based on in vitro data, partially purified extract fractions were then exposed to bacterial colonizers in vivo followed by bacterial enumeration and community analysis. The polar fraction of the algal surface extract revealed a significant profouling effect for Vibrionales, whereas the nonpolar fraction - containing the xanthophyll pigment fucoxanthin and other unidentified nonpolar surface compounds - revealed a significant 80% reduction of surface colonizing bacteria. The analysis of bacterial surface communities by 454 pyrosequencing demonstrated that the antifouling activity of nonpolar algal surface compounds was targeting the abundance of natural bacterial colonizers rather than the relative composition of bacterial members within the community. Moreover, the bacterial community composition on F. vesiculosus was markedly different from artificial control substrates and chemically manipulated experimental treatments, suggesting that other, nonextractable surface features and/or physical properties render algal-specific epiphytic bacterial communities.

  5. [Description of the photosynthetic apparatus of Fucus vesiculosus L. in early embryogenesis].

    PubMed

    Tarakhovskaia, E R; Maslov, Iu I

    2005-01-01

    Dynamics of some photosynthetic parameters was studied in gametes, zygotes, and embryos of kelp Fucus vesiculosus L. The following indices were determined at different stages of early development of the seaweed: the contents of pigments and ribulose-1,5-bisphosphate carboxylase/oxygenase, the rates of photosynthesis and dark respiration, and the activities of photosystems I and II. The dynamics of photosynthetic apparatus activity in zygotes and embryos of F. vesiculosus proved to reflect the main physiological processes of its early development.

  6. Divergence within and among Seaweed Siblings (Fucus vesiculosus and F. radicans) in the Baltic Sea.

    PubMed

    Ardehed, Angelica; Johansson, Daniel; Sundqvist, Lisa; Schagerström, Ellen; Zagrodzka, Zuzanna; Kovaltchouk, Nikolaj A; Bergström, Lena; Kautsky, Lena; Rafajlovic, Marina; Pereyra, Ricardo T; Johannesson, Kerstin

    2016-01-01

    Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more

  7. Divergence within and among Seaweed Siblings (Fucus vesiculosus and F. radicans) in the Baltic Sea

    PubMed Central

    Ardehed, Angelica; Johansson, Daniel; Sundqvist, Lisa; Schagerström, Ellen; Zagrodzka, Zuzanna; Kovaltchouk, Nikolaj A.; Bergström, Lena; Kautsky, Lena; Rafajlovic, Marina; Pereyra, Ricardo T.

    2016-01-01

    Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more

  8. Salinity affects compositional traits of epibacterial communities on the brown macroalga Fucus vesiculosus.

    PubMed

    Stratil, Stephanie B; Neulinger, Sven C; Knecht, Henrik; Friedrichs, Anette K; Wahl, Martin

    2014-05-01

    Epibiotic biofilms have the potential to control major aspects of the biology and ecology of their hosts. Their composition and function may thus be essential for the health of the host. We tested the influence of salinity on the composition of epibacterial communities associated with the brown macroalga Fucus vesiculosus. Algal individuals were incubated at three salinities (5, 19, and 25) for 14 days and nonliving reference substrata (stones) were included in the experiment. Subsequently, the composition of their surface-associated bacterial communities was analyzed by 454 pyrosequencing of 16S rRNA gene sequences. Redundancy analysis revealed that the composition of epiphytic and epilithic communities significantly differed and were both affected by salinity. We found that 5% of 2494 epiphytic operational taxonomic units at 97% sequence similarity were responsible for the observed shifts. Epibacterial α-diversity was significantly lower at salinity 5 but did not differ between substrata. Our results indicate that salinity is an important factor in structuring alga-associated epibacterial communities with respect to composition and/or diversity. Whether direct or indirect mechanisms (via altered biotic interactions) may have been responsible for the observed shifts is discussed.

  9. Temperature-driven shifts in the epibiotic bacterial community composition of the brown macroalga Fucus vesiculosus.

    PubMed

    Stratil, Stephanie B; Neulinger, Sven C; Knecht, Henrik; Friedrichs, Anette K; Wahl, Martin

    2013-04-01

    The thallus surface of the brown macroalga Fucus vesiculosus is covered by a specific biofilm community. This biofilm supposedly plays an important role in the interaction between host and environment. So far, we know little about compositional or functional shifts of this epibiotic bacterial community under changing environmental conditions. In this study, the response of the microbiota to different temperatures with respect to cell density and community composition was analyzed by nonculture-based methods (denaturing gradient gel electrophoresis and 454 pyrosequencing of the 16S rRNA gene). Redundancy analysis showed that despite high variability among host individuals temperature accounted for 20% of the variation in the bacterial community composition, whereas cell density did not differ between groups. Across all samples, 4341 bacterial operational taxonomic units (OTUs) at a 97% similarity level were identified. Eight percent of OTUs were significantly correlated with low, medium, and high temperatures. Notably, the family Rhodobacteraceae increased in relative abundance from 20% to 50% with increasing temperature. OTU diversity (evenness and richness) was higher at 15 °C than at the lower and higher temperatures. Considering their known and presumed ecological functions for the host, change in the epibacterial community may entail shifts in the performance of the host alga.

  10. The effect of Fucus vesiculosus on the grazing of harpacticoid copepods on diatom biofilms

    NASA Astrophysics Data System (ADS)

    De Troch, M.; Chepurnov, V. A.; Vincx, M.; Ólafsson, E.

    2008-10-01

    The effect of Fucus vesiculosus on the functional traits of three harpacticoid copepod species ( Tigriopus brevicornis, Paramphiascella fulvofasciata and Microarthridion littorale) was studied. These copepods are likely to be important grazers on biofilms consisting mainly of diatoms. Several microcosms were created using diatom cultures ( Navicula phyllepta and Seminavis robusta) and vegetative thalli of Fucus, with the biofilm associated, collected from the field. The diatoms were enriched in the stable carbon 13C to facilitate tracing in the harpacticoids. The biofilm on the Fucus was labeled through impregnation of the Fucus leaves in 13C enriched seawater. In all treatments a measurable uptake of diatoms was found for the three copepod species. All copepods showed a low uptake of labeled material when only Fucus thalli were available. The grazing on the benthic diatoms was negatively affected by the presence of the Fucus thalli in the case of P. fulvofasciata. One species, T. brevicornis, grazed efficiently both on sedimentary and epiphytic biofilms. We hereby proved experimentally that benthic harpacticoid copepods are able to switch their food uptake under different habitat/food circumstances. This variety of food uptake is an illustration of the so-called 'niche complementarity effect' that lies at the basis of diverse communities.

  11. Stable isotope signatures and element stoichiometry of Fucus vesiculosus as indicators for environmental conditions in the Kiel Bight, Baltic Sea

    NASA Astrophysics Data System (ADS)

    Winde, Vera; Mahler, Annika; Voss, Maren; Böttcher, Michael E.

    2014-05-01

    In the frame of the BMBF project BIOACID II we aim for an understanding of the natural distribution and variation of isotopic composition and C-N-S stoichiometry in Fucus vesiculosus growing around the coast line of the Kiel fjord (part of the Kiel bight). Environmental conditions (aquatic chemistry, temperature, salinity) were monitored, too. Some changes in aquatic chemistry are related to stress factors like human activity (e.g., waste input) and further factors leading to specific changes in the composition of Fucus vesiculosus. Sampling was carried out at different stations at the west and east coast of the Kiel Fjord. For each sampling station the aquatic chemistry (TA, pH, salinity, d13C(DIC), main and trace elements and nutrients) as well as the composition of the Fucus organic tissues (stoichiometry and stable isotope composition of carbon, nitrogen) are analysed. The Fucus tissue was sampled in three size classes (small, medium, large). It is shown, that Fucus vesiculosus indicates clear differences in the N contents and stable isotopes between the west and the east site of the Kiel Fjord. Stable nitrogen isotope signatures in Fucus vesiculosus, are useful proxies to identify the influence factors in the Fucus habitat. From the data it is obtained that the influence of human activity (wastewater treatment plant, harbour), small stream and drainage channels, which flow from the near coastal area into the bight, leads to different Fucus vesiculosus compositions. In future work, it is intended to extend the investigation to trace element signatures to further estimate environmental impacts.

  12. An expressed sequence tag analysis of the intertidal brown seaweeds Fucus serratus (L.) and F. vesiculosus (L.) (Heterokontophyta, Phaeophyceae) in response to abiotic stressors.

    PubMed

    Pearson, Gareth A; Hoarau, Galice; Lago-Leston, Asuncion; Coyer, James A; Kube, Michael; Reinhardt, Richard; Henckel, Kolja; Serrão, Ester T A; Corre, Erwan; Olsen, Jeanine L

    2010-04-01

    In order to aid gene discovery and uncover genes responding to abiotic stressors in stress-tolerant brown algae of the genus Fucus, expressed sequence tags (ESTs) were studied in two species, Fucus serratus and Fucus vesiculosus. Clustering of over 12,000 ESTs from three libraries for heat shock/recovery and desiccation/rehydration resulted in identification of 2,503, 1,290, and 2,409 unigenes from heat-shocked F. serratus, desiccated F. serratus, and desiccated F. vesiculosus, respectively. Low overall annotation rates (18-31%) were strongly associated with the presence of long 3' untranslated regions in Fucus transcripts, as shown by analyses of predicted protein-coding sequence in annotated and nonannotated tentative consensus sequences. Posttranslational modification genes were overrepresented in the heat shock/recovery library, including many chaperones, the most abundant of which were a family of small heat shock protein transcripts, Hsp90 and Hsp70 members. Transcripts of LI818-like light-harvesting genes implicated in photoprotection were also expressed during heat shock in high light. The expression of several heat-shock-responsive genes was confirmed by quantitative reverse transcription polymerase chain reaction. However, candidate genes were notably absent from both desiccation/rehydration libraries, while the responses of the two species to desiccation were divergent, perhaps reflecting the species-specific physiological differences in stress tolerance previously established. Desiccation-tolerant F. vesiculosus overexpressed at least 17 ribosomal protein genes and two ubiquitin-ribosomal protein fusion genes, suggesting that ribosome function and/or biogenesis are important during cycles of rapid desiccation and rehydration in the intertidal zone and possibly indicate parallels with other poikilohydric organisms such as desiccation-tolerant bryophytes.

  13. Interannual changes in δ¹⁵N values in Fucus vesiculosus L.

    PubMed

    Carballeira, Carlos; Rey-Asensio, Ana; Carballeira, Alejo

    2014-08-15

    The natural abundance of (15)N (δ(15)N) has been widely used to detect anthropogenically derived N loads in environmental impact studies. The present study involved retrospective analysis of subsamples of Fucus vesiculosus L. collected during a period of three years (2008-2010) from two sites: a control site, within a coastal reference area, and an area affected by the effluents of a marine land-based fish farm. The isotopic signal in different subsamples of the macroalgae thalli (tissue that has grown during the same period) varied depending on the age of the tissue. Moreover, the isotopic signal decreased significantly with the age of the frond to within a certain range. The δ(15)N of F. vesiculosus is temporally unstable; therefore, measurement of the δ(15)N of macroalgal tissues does not allow reliable retrospective biomonitoring of environmental pollution. Further knowledge about the growth and other biological aspects of this species is required.

  14. Determination of the Cd/S cluster stoichiometry in Fucus vesiculosus metallothionein.

    PubMed

    Merrifield, Maureen E; Chaseley, Jennifer; Kille, Peter; Stillman, Martin J

    2006-03-01

    The seaweed Fucus vesiculosus is unusual when compared with other algal species, in that it can survive in toxic-metal-contaminated aquatic environments. The metallothionein gene has been identified in F. vesiculosus by Kille and co-workers (Morris, C. A., Nicolaus, B., Sampson, V., Harwood, J. L., and Kille, P. (1999) Biochem. J. 338, 553), which suggests a possible protective mechanism against toxic metals for this species. We report the first detailed study of the metal binding properties of F. vesiculosus metallothionein using UV absorption, circular dichroism (CD), and electrospray mass spectral techniques. The overall metal-to-sulfur ratios of this novel algal protein when bound to divalent cadmium and zinc were determined to be Cd(6)S(16) and Zn(6)S(16), respectively. Mixed Cd/Zn species were also formed when Cd(2+) was added to the Zn-containing Fucus metallothionein. Only one conformation was identified at low pH for the native protein. Analysis of the UV absorption, CD, and ESI-MS spectral data recorded during stepwise, acid-induced demetalation supports a two-domain structure for the protein, with two 3-metal binding sites. The data suggest that one of the domains is significantly less stable than the other, and we tentatively propose from the arrangement of cysteines in the sequence that the two domains are M(3)S(7) and M(3)S(9) (where M = Cd(2+) or Zn(2+)). While the M(3)S(9) cluster is known in the beta clusters of crab, lobster, and mammalian metallothioneins, the M(3)S(7) is a hitherto unknown cluster structure. Metallothionein in F. vesiculosus is thought to act as a protective mechanism against incoming toxic metals. The metal binding studies reported are a putative model for metal binding in vivo.

  15. Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells

    PubMed Central

    Geisen, Ulf; Zenthoefer, Marion; Peipp, Matthias; Kerber, Jannik; Plenge, Johannes; Managò, Antonella; Fuhrmann, Markus; Geyer, Roland; Hennig, Steffen; Adam, Dieter; Piker, Levent; Rimbach, Gerald; Kalthoff, Holger

    2015-01-01

    Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1). Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data) and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application. PMID:26204945

  16. Molecular Mechanisms by Which a Fucus vesiculosus Extract Mediates Cell Cycle Inhibition and Cell Death in Pancreatic Cancer Cells.

    PubMed

    Geisen, Ulf; Zenthoefer, Marion; Peipp, Matthias; Kerber, Jannik; Plenge, Johannes; Managò, Antonella; Fuhrmann, Markus; Geyer, Roland; Hennig, Steffen; Adam, Dieter; Piker, Levent; Rimbach, Gerald; Kalthoff, Holger

    2015-07-20

    Pancreatic cancer is one of the most aggressive cancer entities, with an extremely poor 5-year survival rate. Therefore, novel therapeutic agents with specific modes of action are urgently needed. Marine organisms represent a promising source to identify new pharmacologically active substances. Secondary metabolites derived from marine algae are of particular interest. The present work describes cellular and molecular mechanisms induced by an HPLC-fractionated, hydrophilic extract derived from the Baltic brown seaweed Fucus vesiculosus (Fv1). Treatment with Fv1 resulted in a strong inhibition of viability in various pancreatic cancer cell lines. This extract inhibited the cell cycle of proliferating cells due to the up-regulation of cell cycle inhibitors, shown on the mRNA (microarray data) and protein level. As a result, cells were dying in a caspase-independent manner. Experiments with non-dividing cells showed that proliferation is a prerequisite for the effectiveness of Fv1. Importantly, Fv1 showed low cytotoxic activity against non-malignant resting T cells and terminally differentiated cells like erythrocytes. Interestingly, accelerated killing effects were observed in combination with inhibitors of autophagy. Our in vitro data suggest that Fv1 may represent a promising new agent that deserves further development towards clinical application.

  17. Toxicity and antioxidant activity in vitro and in vivo of two Fucus vesiculosus extracts.

    PubMed

    Zaragozá, M C; López, D; P Sáiz, M; Poquet, M; Pérez, J; Puig-Parellada, P; Màrmol, F; Simonetti, P; Gardana, C; Lerat, Y; Burtin, P; Inisan, C; Rousseau, I; Besnard, M; Mitjavila, M T

    2008-09-10

    The consumption of seaweeds has increased in recent years. However, their adverse and beneficial effects have scarcely been studied. Two extracts from the brown seaweed Fucus vesiculosus containing 28.8% polyphenols or 18% polyphenols plus 0.0012% fucoxanthin have been obtained and studied to determine their toxicity in mice and rats and also their antioxidant activity. Both extracts were shown to lack any relevant toxic effects in an acute toxicity test following a 4 week daily treatment in rats. The extracts exhibited antioxidant activity in noncellular systems and in activated RAW 264.7 macrophages, as well as in ex vivo assays in plasma and erythrocytes, after the 4 week treatment in rats. Our ex vivo results indicated that compounds from extract 2 may be more easily absorbed and that the antioxidants in their parent or metabolized form are more active. These findings support the view that the daily consumption of F. vesiculosus extract 2 (Healsea) would have potential benefits to humans.

  18. Effect studies of human pharmaceuticals on Fucus vesiculosus and Gammarus spp.

    PubMed

    Oskarsson, Hanna; Eriksson Wiklund, Ann-Kristin; Lindh, Karolina; Kumblad, Linda

    2012-03-01

    In two experiments, the human pharmaceutical propranolol negatively affected the physiology of two test organisms, Fucus vesiculosus and Gammarus spp. from a Baltic Sea littoral community in a concentration of 1000 μg l⁻¹. Some effects were also observed for the lower, more ecologically relevant concentrations (10 μg l⁻¹ and 100 μg l⁻¹). The effects on F. vesiculosus not only increased with increasing concentration, but also with exposure time; while the effects on Gammarus spp. were more inconsistent over time. No clear effects of the pharmaceuticals diclofenac and ibuprofen were observed for any of the organisms. Physiological parameters measured were GP:R-ratio, chlorophyll fluorescence and release of coloured dissolved organic matter, respiration and ammonium excretion. Pharmaceutical substances are repeatedly detected in the Baltic Sea which is the recipient for STP effluents from more than 85 million people living in the catchment area, but the knowledge of their effects on non-target organisms is still very limited.

  19. Nitrate uptake varies with tide height and nutrient availability in the intertidal seaweed Fucus vesiculosus.

    PubMed

    Benes, Kylla M; Bracken, Matthew E S

    2016-10-01

    Intertidal seaweeds must cope with a suite of stressors imposed by aerial exposure at low tide, including nutrient limitation due to emersion. Seaweeds can access nutrients only when submerged, so individuals living higher compared to lower on the shore may have adaptations allowing them to acquire sufficient amounts of nutrients to survive and maintain growth. Using a combination of observations and experiments, we aimed to identify intraspecific variation in nitrate uptake rates across the intertidal distribution of F. vesiculosus, as well as test for acclimation in response to a change in tide height. We replicated our study at sites spanning nearly the entire Gulf of Maine coastline, to examine how local environmental variability may alter intraspecific variation in nitrate uptake. We found that average nitrate uptake rates were ~18% higher in upper compared to lower intertidal Fucus vesiculosus. Furthermore, we found evidence for both acclimation and adaptation to tide height during a transplant experiment. F. vesiculosus transplanted from the lower to the upper intertidal zone was characterized by increased nitrate uptake, but individuals transplanted from the upper to the lower intertidal zone retained high uptake rates. Our observations differed among Gulf of Maine regions and among time points of our study. Importantly, these differences may reflect associations between nitrate uptake rates and abiotic environmental conditions and seaweed nutrient status. Our study highlights the importance of long-term variation in ambient nutrient supply in driving intraspecific variation of seaweeds across the intertidal gradient and local and seasonal variation in ambient nutrient levels in mediating intraspecific differences.

  20. Modelling 99Tc concentrations in Fucus vesiculosus from the north-east Irish Sea.

    PubMed

    Nawakowski, Claire; Nicholson, Michael D; Kershaw, Peter John; Leonard, Kinson S

    2004-01-01

    In 1994 there were substantial increases in the quantity of 99Tc discharged into the north-east Irish Sea from BNFL Sellafield (UK), concomitant with improvements in waste treatment procedures. As a consequence, the concentration of 99Tc observed in seawater and biota samples, taken from the Irish Sea coastline, increased significantly. Elevated concentrations were also reported in Dutch, Danish, Norwegian, Swedish and Arctic waters in subsequent years. In the present study a simple numerical model was developed and applied to time-series data of 99Tc concentrations in the brown seaweed Fucus vesiculosus, collected from three UK sites in the vicinity of Sellafield (St. Bees, Heysham, Port William). The model considered site-specific scaling effects, lag times, previous discharge history and potential seasonal variation in uptake. In general, there was a good fit between predicted and observed concentrations, but the degree of uncertainty varied inversely with the frequency of sampling. We did not observe a significant seasonal variation. The modelled lag times to the three sites were consistent with transport times based on observations of the water column distribution of 99Tc. The model was applied to a variety of discharge scenarios, reflecting current discussion on the future management of 99Tc releases. Concentrations in Fucus reached asymptotic values in 3-10 years, depending on the scenario and sampling site under consideration.

  1. Arsenic metalation of seaweed Fucus vesiculosus metallothionein: the importance of the interdomain linker in metallothionein.

    PubMed

    Ngu, Thanh T; Lee, Janice A; Rushton, Moira K; Stillman, Martin J

    2009-09-22

    The presence of metallothionein in seaweed Fucus vesiculosus has been suggested as the protecting agent against toxic metals in the contaminated waters it can grow in. We report the first kinetic pathway data for A3+ binding to an algal metallothionein, F. vesiculosus metallothionein (rfMT). The time and temperature dependence of the relative concentrations of apo-rfMT and the five As-containing species have been determined following mixing of As3+ and apo-rfMT using electrospray ionization mass spectrometry (ESI MS). Kinetic analysis of the detailed time-resolved mass spectral data for As3+ metalation allows the simulation of the metalation reactions showing the consumption of apo-rfMT, the formation and consumption of As1- to As4-rfMT, and subsequent, final formation of As5-rfMT. The kinetic model proposed here provides a stepwise analysis of the metalation reaction showing time-resolved occupancy of the Cys7 and the Cys9 domain. The rate constants (M(-1) s(-1)) calculated from the fits for the 7-cysteine gamma domain are k1gamma, 19.8, and k2gamma, 1.4, and for the 9-cysteine beta domain are k1beta, 16.3, k2beta, 9.1, and k3beta, 2.2. The activation energies and Arrhenius factors for each of the reaction steps are also reported. rfMT has a long 14 residue linker, which as we show from analysis of the ESI MS data, allows each of its two domains to bind As3+ independently of each other. The analysis provides for the first time an explanation of the differing metal-binding properties of two-domain MTs with linkers of varying lengths, suggesting further comparison between plant (with long linkers) and mammalian (with short linkers) metallothioneins will shed light on the role of the interdomain linker.

  2. Genetic entities and mating system in hermaphroditic Fucus spiralis and its close dioecious relative F. vesiculosus (Fucaceae, Phaeophyceae).

    PubMed

    Engel, C R; Daguin, C; Serrão, E A

    2005-06-01

    To date, molecular markers have not settled the question of the specific status of the closely related, but phylogenetically unresolved, brown seaweeds, hermaphroditic Fucus spiralis and dioecious Fucus vesiculosus, nor their propensity for natural hybridization. To test the degree of species integrity and to assess effect of the mating system on the population genetic structure, 288 individuals coming from parapatric (discontinuous) and sympatric (contiguous) spatial configurations at two sites were genotyped with five microsatellite loci. Using a Bayesian admixture analysis, our results show that F. spiralis and F. vesiculosus comprise clearly distinct genetic entities (clusters) generally characterized by cosexual and unisexual individuals, respectively. Genetic diversity within each entity suggests that F. spiralis reproduces primarily through selfing while F. vesiculosus is characterized by an endogamous breeding regime. Nevertheless, aberrant sexual phenotypes were observed in each cluster, no diagnostic alleles were revealed and 10% of study individuals were intermediate between the two genetic entities. This pattern can be explained by recent divergence of two taxa with retention of ancestral polymorphism or asymmetrical, introgressive hybridization. However, given (i) coincident monomorphism at three loci in spiralis clusters and (ii) that significantly more intermediates were observed in sympatric stations than in parapatric stations, we argue that interspecific gene flow has occurred after divergence of the two taxa. Finally, we show that whether recently separated or recently introgressive, the divergent breeding systems probably contribute to species integrity in these two taxa.

  3. Dissolved organic carbon reduces the toxicity of copper to germlings of the macroalgae, Fucus vesiculosus.

    PubMed

    Brooks, Steven J; Bolam, Thi; Tolhurst, Laura; Bassett, Janice; La Roche, Jay; Waldock, Mike; Barry, Jon; Thomas, Kevin V

    2008-05-01

    This study investigates the effects of waterborne copper exposure on germling growth in chemically defined seawater. Germlings of the macroalgae, Fucus vesiculosus were exposed to a range of copper and dissolved organic carbon (DOC as humic acid) concentrations over 14 days. Germling growth was found to be a sensitive indicator of copper exposure with total copper (TCu) and labile copper (LCu) EC(50) values of approximately 40 and 20 microg/L, respectively, in the absence of added DOC. The addition of DOC into the exposure media provided germlings with protection against copper toxicity, with an increased TCu EC(50) value of 117.3 microg/L at a corrected DOC (cDOC from humic acid only) concentration of 2.03 mg/L. The LCu EC(50) was not affected by a cDOC concentration of 1.65 mg/L or less, suggesting that the LCu concentration not the TCu concentration was responsible for inhibiting germling growth. However, at a cDOC concentration of approximately 2mg/L an increase in the LCu EC(50) suggests that the LCu concentration may play a role in the overall toxicity to the germlings. This is contrary to current understanding of aquatic copper toxicity and possible explanations for this are discussed.

  4. Structure-activity relationship of the pro- and anticoagulant effects of Fucus vesiculosus fucoidan.

    PubMed

    Zhang, Z; Till, S; Jiang, C; Knappe, S; Reutterer, S; Scheiflinger, F; Szabo, C M; Dockal, M

    2014-03-03

    Fucoidan is a highly complex sulfated polysaccharide commonly extracted from brown seaweed. In addition to their many biological activities, fucoidans have recently been demonstrated to inhibit or increase coagulation at different concentration ranges. Their structural features, i.e. molecular weight (Mw), Mw distribution, degree of sulfation, monosaccharide composition, and different linkages, are known to affect these activities. Therefore, structure-activity relationship (SAR) analysis of fucoidan is crucial for its potential use as a procoagulant. In this study, Fucus vesiculosus (F.v.) fucoidan was fractionated by charge and size as well as over- and desulfated to different degrees to yield preparations with various structural properties. The fractions' pro- and anticoagulant activities were assessed by calibrated automated thrombography (CAT) and activated partial thromboplastin time(aPTT) assays. Binding to and inhibition of the anticoagulant protein tissue factor pathway inhibitor (TFPI) and the ability to activate coagulation via the contact pathway were also investigated. This paper discusses the impact of charge density, size, and sugar composition on fucoidan's pro- and anticoagulant activities. Fucoidan requires a minimal charge density of 0.5 sulfates per sugar unit and a size of 70 sugar units to demonstrate desired procoagulant activities for improvement of haemostasis in factor VIII/factor IX-deficient plasma.

  5. Genetic variation in photosynthetic performance and tolerance to osmotic stress (desiccation, freezing, hyposalinity) in the rocky littoral foundation species Fucus vesiculosus (Fucales, Phaeophyceae).

    PubMed

    Rothäusler, Eva; Sjöroos, Joakim; Heye, Katharina; Jormalainen, Veijo

    2016-10-01

    Genetic diversity may play an analogous role to species diversity, as it can contribute to ecosystem function and stability, and provision of ecosystem services. In the Baltic Sea, perennial algal beds are often comprised of only Fucus vesiculosus and the amount of genetic variation in fitness-related traits (i.e., the ability of the alga to photosynthesize or withstand stress) will thus determine the alga's local persistence in a changing environment. To study genetic variation in the crucial traits behind persistence we grew replicate vegetative branches that came from the same genotype in common gardens. We quantified osmotic stress tolerance and recovery responses by exposing branches to desiccation, freezing, and hyposalinity regimens. Our results show that genetic variation among genotypes was apparent for some photosynthetic parameters (maximal electron transport rate, saturation irradiance for electron transport, nonphotochemical quenching) and growth. Algae tolerated freezing (1,440 min at -2.5°C) and hyposalinity (1,560 min at 2.5) well, but did not recover from desiccation (70 min at 12°C, causing ~94% water loss). Furthermore, we found very little if any evidence on genetic variation in tolerance to these stressors. Our results suggest that low salinity and cold winters in the northern marginal populations selected for hyposalinity and freezing tolerant genotypes, possibly eroding genetic variation in tolerance, but that tolerance to harsh desiccation has been lost, likely due to relaxed selection. The overall availability of genetic variation in fitness related traits might be supportive for F. vesiculosus during adaptation to gradual changes of its environment.

  6. Physicochemical and Biological Characterization of Fucoidan from Fucus vesiculosus Purified by Dye Affinity Chromatography

    PubMed Central

    Zayed, Ahmed; Muffler, Kai; Hahn, Thomas; Rupp, Steffen; Finkelmeier, Doris; Burger-Kentischer, Anke; Ulber, Roland

    2016-01-01

    A comparative study concerning the physicochemical, monomeric composition and biological characters among different fucoidan fractions is presented. Common purification techniques for fucoidan usually involve many steps. During these steps, the important structural features might be affected and consequently alter its biological activities. Three purified fractions were derived from Fucus vesiculosus water extract which, afterwards, were purified by a recently-developed dye affinity chromatography protocol. This protocol is based on dye-sulfated polysaccharide interactions. The first two fractions were obtained from crude precipitated fucoidan at different pH values of the adsorption phase: pH 1 and 6. This procedure resulted in fucoidan_1 and 6 fractions. The other, third, fraction: fucoidan_M, however, was obtained from a buffered crude extract at pH 1, eliminating the ethanol precipitation step. All of the three fractions were then further evaluated. Results revealed that fucoidan_M showed the highest sulfur content (S%), 12.11%, with the lowest average molecular weight, 48 kDa. Fucose, galactose, and uronic acid/glucose dimers were detected in all fractions, although, xylose was only detected in fucoidan_1 and 6. In a concentration of 10 µg·mL−1, Fucoidan_6 showed the highest heparin-like anticoagulant activity and could prolong the APTT and TT significantly to 66.03 ± 2.93 and 75.36 ± 1.37 s, respectively. In addition, fucoidan_M demonstrated the highest potency against HSV-1 with an IC50 of 2.41 µg·mL−1. The technique proved to be a candidate for fucoidan purifaction from its crude extract removing the precipitation step from common purification protocols and produced different fucoidan qualities resulted from the different incubation conditions with the immobilized thiazine toluidine blue O dye. PMID:27092514

  7. Fucoidan from Fucus vesiculosus Fails to Improve Outcomes Following Intracerebral Hemorrhage in Mice.

    PubMed

    Burchell, Sherrefa R; Iniaghe, Loretta O; Zhang, John H; Tang, Jiping

    2016-01-01

    Intracerebral hemorrhage (ICH) is the most fatal stroke subtype, with no effective therapies. Hematoma expansion and inflammation play major roles in the pathophysiology of ICH, contributing to primary and secondary brain injury, respectively. Fucoidan, a polysaccharide from the brown seaweed Fucus vesiculosus, has been reported to activate a platelet receptor that may function in limiting bleeding, and to exhibit anti-inflammatory effects. As such, the aim of the present study was to examine the effects of fucoidan on hemorrhaging and neurological outcomes after ICH. Male CD-1 mice were subjected to experimental ICH by infusion of bacterial collagenase. Animals were randomly divided into the following groups: sham, ICH + vehicle, ICH + 25 mg/kg fucoidan, ICH + 75 mg/kg fucoidan, and ICH + 100 mg/kg fucoidan. Brain water content, neurobehavioral outcomes, and hemoglobin content were evaluated at 24 h post ICH. Our findings show that fucoidan failed to attenuate the ICH-induced increase in BWC. The neurological deficits that result from ICH also did not differ in the treatment groups at all three doses. Finally, we found that fucoidan had no effect on the hemoglobin content after ICH. We postulate that fucoidan treatment did not improve the measured outcomes after ICH because we used crude fucoidan, which has a high molecular weight, in our study. High-molecular-weight fucoidans are reported to have less therapeutic potential than low molecular weight fucoidans. They have been shown to exhibit anti-coagulant and pro-apoptotic properties, which seem to outweigh their anti-inflammatory and potential procoagulant abilities. We propose that using a low-molecular-weight fucoidan, or fractionating the crude polysaccharide, may be effective in treating ICH. Future studies are needed to confirm this.

  8. Physicochemical and Biological Characterization of Fucoidan from Fucus vesiculosus Purified by Dye Affinity Chromatography.

    PubMed

    Zayed, Ahmed; Muffler, Kai; Hahn, Thomas; Rupp, Steffen; Finkelmeier, Doris; Burger-Kentischer, Anke; Ulber, Roland

    2016-04-15

    A comparative study concerning the physicochemical, monomeric composition and biological characters among different fucoidan fractions is presented. Common purification techniques for fucoidan usually involve many steps. During these steps, the important structural features might be affected and consequently alter its biological activities. Three purified fractions were derived from Fucus vesiculosus water extract which, afterwards, were purified by a recently-developed dye affinity chromatography protocol. This protocol is based on dye-sulfated polysaccharide interactions. The first two fractions were obtained from crude precipitated fucoidan at different pH values of the adsorption phase: pH 1 and 6. This procedure resulted in fucoidan_1 and 6 fractions. The other, third, fraction: fucoidan_M, however, was obtained from a buffered crude extract at pH 1, eliminating the ethanol precipitation step. All of the three fractions were then further evaluated. Results revealed that fucoidan_M showed the highest sulfur content (S%), 12.11%, with the lowest average molecular weight, 48 kDa. Fucose, galactose, and uronic acid/glucose dimers were detected in all fractions, although, xylose was only detected in fucoidan_1 and 6. In a concentration of 10 µg·mL(-1), Fucoidan_6 showed the highest heparin-like anticoagulant activity and could prolong the APTT and TT significantly to 66.03 ± 2.93 and 75.36 ± 1.37 s, respectively. In addition, fucoidan_M demonstrated the highest potency against HSV-1 with an IC50 of 2.41 µg·mL(-1). The technique proved to be a candidate for fucoidan purifaction from its crude extract removing the precipitation step from common purification protocols and produced different fucoidan qualities resulted from the different incubation conditions with the immobilized thiazine toluidine blue O dye.

  9. Defence Chemistry Modulation by Light and Temperature Shifts and the Resulting Effects on Associated Epibacteria of Fucus vesiculosus

    PubMed Central

    Saha, Mahasweta; Rempt, Martin; Stratil, Stephanie B.; Wahl, Martin; Pohnert, Georg; Weinberger, Florian

    2014-01-01

    The goals of this study were (1) to investigate whether Fucus vesiculosus regulates the production of its antifouling defence chemicals against epibacteria in response to light limitation and temperature shifts and (2) to investigate if different surface concentrations of defence compounds shape epibacterial communities. F. vesiculosus was incubated in indoor mesocosms at five different temperature conditions (5 to 25°C) and in outdoor mesocosms under six differently reduced sunlight conditions (0 to 100%), respectively. Algal surface concentrations of previously identified antifouling compounds - dimethylsulphopropionate (DMSP), fucoxanthin and proline – were determined and the bacterial community composition was characterized by in-depth sequencing of the 16S-rRNA gene. Altogether, the effect of different treatment levels upon defence compound concentrations was limited. Under all conditions DMSP alone appeared to be sufficiently concentrated to warrant for at least a partial inhibitory action against epibiotic bacteria of F. vesiculosus. In contrast, proline and fucoxanthin rarely reached the necessary concentration ranges for self-contained inhibition. Nonetheless, in both experiments along with the direct influence of temperature and light, all three compounds apparently affected the overall bacterial community composition associated with F. vesiculosus since tendencies for insensitivity towards all three compounds were observed among bacterial taxa that typically dominate those communities. Given that the concentrations of at least one of the compounds (in most cases DMSP) were always high enough to inhibit bacterial settlement, we conclude that the capacity of F. vesiculosus for such defence will hardly be compromised by shading or warming to temperatures up to 25°C. PMID:25360717

  10. Defence chemistry modulation by light and temperature shifts and the resulting effects on associated epibacteria of Fucus vesiculosus.

    PubMed

    Saha, Mahasweta; Rempt, Martin; Stratil, Stephanie B; Wahl, Martin; Pohnert, Georg; Weinberger, Florian

    2014-01-01

    The goals of this study were (1) to investigate whether Fucus vesiculosus regulates the production of its antifouling defence chemicals against epibacteria in response to light limitation and temperature shifts and (2) to investigate if different surface concentrations of defence compounds shape epibacterial communities. F. vesiculosus was incubated in indoor mesocosms at five different temperature conditions (5 to 25°C) and in outdoor mesocosms under six differently reduced sunlight conditions (0 to 100%), respectively. Algal surface concentrations of previously identified antifouling compounds--dimethylsulphopropionate (DMSP), fucoxanthin and proline--were determined and the bacterial community composition was characterized by in-depth sequencing of the 16S-rRNA gene. Altogether, the effect of different treatment levels upon defence compound concentrations was limited. Under all conditions DMSP alone appeared to be sufficiently concentrated to warrant for at least a partial inhibitory action against epibiotic bacteria of F. vesiculosus. In contrast, proline and fucoxanthin rarely reached the necessary concentration ranges for self-contained inhibition. Nonetheless, in both experiments along with the direct influence of temperature and light, all three compounds apparently affected the overall bacterial community composition associated with F. vesiculosus since tendencies for insensitivity towards all three compounds were observed among bacterial taxa that typically dominate those communities. Given that the concentrations of at least one of the compounds (in most cases DMSP) were always high enough to inhibit bacterial settlement, we conclude that the capacity of F. vesiculosus for such defence will hardly be compromised by shading or warming to temperatures up to 25°C.

  11. The Phytocomplex from Fucus vesiculosus and Ascophyllum nodosum Controls Postprandial Plasma Glucose Levels: An In Vitro and In Vivo Study in a Mouse Model of NASH.

    PubMed

    Gabbia, Daniela; Dall'Acqua, Stefano; Di Gangi, Iole Maria; Bogialli, Sara; Caputi, Valentina; Albertoni, Laura; Marsilio, Ilaria; Paccagnella, Nicola; Carrara, Maria; Giron, Maria Cecilia; De Martin, Sara

    2017-02-15

    Edible seaweeds have been consumed by Asian coastal communities since ancient times. Fucus vesiculosus and Ascophyllum nodosum extracts have been traditionally used for the treatment of obesity and several gastrointestinal diseases. We evaluated the ability of extracts obtained from these algae to inhibit the digestive enzymes α-amylase and α-glucosidase in vitro, and control postprandial plasma glucose levels in a mouse model of non-alcoholic steatohepatitis (NASH); a liver disease often preceding the development of Type 2 diabetes (T2DM). This model was obtained by the administration of a high-fat diet. Our results demonstrate that these algae only delayed and reduced the peak of blood glucose (p < 0.05) in mice fed with normal diet, without changing the area under the blood glucose curve (AUC). In the model of NASH, the phytocomplex was able to reduce both the postprandial glycaemic peak, and the AUC. The administration of the extract in a diet particularly rich in fat is associated with a delay in carbohydrate digestion, but also with a decrease in its assimilation. In conclusion, our results indicate that this algal extract may be useful in the control of carbohydrate digestion and absorption. This effect may be therapeutically exploited to prevent the transition of NASH to T2DM.

  12. The Phytocomplex from Fucus vesiculosus and Ascophyllum nodosum Controls Postprandial Plasma Glucose Levels: An In Vitro and In Vivo Study in a Mouse Model of NASH

    PubMed Central

    Gabbia, Daniela; Dall’Acqua, Stefano; Di Gangi, Iole Maria; Bogialli, Sara; Caputi, Valentina; Albertoni, Laura; Marsilio, Ilaria; Paccagnella, Nicola; Carrara, Maria; Giron, Maria Cecilia; De Martin, Sara

    2017-01-01

    Edible seaweeds have been consumed by Asian coastal communities since ancient times. Fucus vesiculosus and Ascophyllum nodosum extracts have been traditionally used for the treatment of obesity and several gastrointestinal diseases. We evaluated the ability of extracts obtained from these algae to inhibit the digestive enzymes α-amylase and α-glucosidase in vitro, and control postprandial plasma glucose levels in a mouse model of non-alcoholic steatohepatitis (NASH); a liver disease often preceding the development of Type 2 diabetes (T2DM). This model was obtained by the administration of a high-fat diet. Our results demonstrate that these algae only delayed and reduced the peak of blood glucose (p < 0.05) in mice fed with normal diet, without changing the area under the blood glucose curve (AUC). In the model of NASH, the phytocomplex was able to reduce both the postprandial glycaemic peak, and the AUC. The administration of the extract in a diet particularly rich in fat is associated with a delay in carbohydrate digestion, but also with a decrease in its assimilation. In conclusion, our results indicate that this algal extract may be useful in the control of carbohydrate digestion and absorption. This effect may be therapeutically exploited to prevent the transition of NASH to T2DM. PMID:28212301

  13. Herb-drug interaction of Fucus vesiculosus extract and amiodarone in rats: a potential risk for reduced bioavailability of amiodarone in clinical practice.

    PubMed

    Rodrigues, Márcio; Alves, Gilberto; Abrantes, João; Falcão, Amílcar

    2013-02-01

    Fucus vesiculosus is a seaweed claimed to be useful for obesity management. Therefore, considering the relationship between obesity and cardiovascular diseases, this work aimed to assess the potential for an herb-drug interaction among a standardized F. vesiculosus extract (GMP certificate) and amiodarone (a narrow therapeutic index drug) in rats. In a first pharmacokinetic study, rats were simultaneously co-administered with a single-dose of F. vesiculosus (575 mg/kg, p.o.) and amiodarone (50 mg/kg, p.o.); in a second study, rats were pre-treated during 14 days with F. vesiculosus (575 mg/kg/day, p.o.) and received amiodarone (50 mg/kg, p.o.) on the 15th day. Rats of the control groups received the corresponding volume of vehicle. After analysis of the pharmacokinetic data it deserves to be highlighted the significant decrease in the peak plasma concentration of amiodarone (55.4%) as well as the reduction of systemic exposure to the parent drug (~30%) following the simultaneous co-administration of F. vesiculosus extract and amiodarone. This paper reports, for the first time, the herb-drug interaction between F. vesiculosus and amiodarone, which determined a considerable decrease on amiodarone bioavailability in rats. Therefore, the therapeutic efficacy of amiodarone may be compromised by the concurrent administration of herbal slimming medicines/dietary supplements containing F. vesiculosus.

  14. Fucoidan from Fucus vesiculosus Protects against Alcohol-Induced Liver Damage by Modulating Inflammatory Mediators in Mice and HepG2 Cells

    PubMed Central

    Lim, Jung Dae; Lee, Sung Ryul; Kim, Taeseong; Jang, Seon-A; Kang, Se Chan; Koo, Hyun Jung; Sohn, Eunsoo; Bak, Jong Phil; Namkoong, Seung; Kim, Hyoung Kyu; Song, In Sung; Kim, Nari; Sohn, Eun-Hwa; Han, Jin

    2015-01-01

    Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg) for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1), a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions. PMID:25690093

  15. Fucoidan from Fucus vesiculosus protects against alcohol-induced liver damage by modulating inflammatory mediators in mice and HepG2 cells.

    PubMed

    Lim, Jung Dae; Lee, Sung Ryul; Kim, Taeseong; Jang, Seon-A; Kang, Se Chan; Koo, Hyun Jung; Sohn, Eunsoo; Bak, Jong Phil; Namkoong, Seung; Kim, Hyoung Kyu; Song, In Sung; Kim, Nari; Sohn, Eun-Hwa; Han, Jin

    2015-02-16

    Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg) for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1), a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions.

  16. RECENT VERSUS RELIC: DISCERNING THE GENETIC SIGNATURE OF FUCUS VESICULOSUS (HETEROKONTOPHYTA; PHAEOPHYCEAE) IN THE NORTHWESTERN ATLANTIC(1).

    PubMed

    Muhlin, Jessica F; Brawley, Susan H

    2009-08-01

    Fucus vesiculosus L. is one of the most widespread macrophytes in the northwestern Atlantic, ranging from North Carolina (USA) to Greenland (DK). We investigated genetic diversity, population differentiation, patterns of isolation by distance, and putative glacial refugial populations across seven locations from North Carolina (USA) to Cape Breton Island, Nova Scotia (Canada), with microsatellite analyses. Distinct northern versus southern (Delaware-North Carolina) populations were revealed by microsatellite data. Five of six microsatellite loci were fixed in populations in North Carolina, suggesting a recent founder event or a bottleneck, and the same homozygous genotype was found in herbarium materials collected on the North Carolina coast from more than 60 years ago. An additional set of individuals from the northern limit in Greenland was included in our analysis of mitochondrial intergenic spacer (mt IGS) haplotypes in the northwestern Atlantic. Remarkably, 184 of 188 F. vesiculosus specimens from North Carolina to Greenland shared the same haplotype. Recent colonization of the North American shore from Europe is hypothesized based upon the ubiquity of this common haplotype, which was earlier reported from Europe.

  17. Effects of fucoidan from Fucus vesiculosus in reducing symptoms of osteoarthritis: a randomized placebo-controlled trial

    PubMed Central

    Myers, Stephen P; Mulder, Ann M; Baker, Don G; Robinson, Shelley R; Rolfe, Margaret I; Brooks, Lyndon; Fitton, J Helen

    2016-01-01

    Purpose Preliminary investigation of a fucoidan with demonstrated reduction in the symptoms of osteoarthritis (OA) of the hip and knee. Patients and methods A double-blind randomized controlled trial was carried out to determine the safety and efficacy of a 300 mg dose of a Fucus vesiculosus extract (85% fucoidan) over a 12-week period in a population (n=122) with mild-to-moderate OA of the hip and knee as measured by the validated instrument “Comprehensive Osteoarthritis Test.” Safety was measured by assessing cholesterol, liver function, renal function, and hematopoietic function, and closely monitoring adverse events. Result Ninety-six participants completed the study. The reduction in symptoms of OA was not significantly different from the placebo response. There were no changes in the blood measurements that were of any clinical significance during the course of the study. Conclusion The F. vesiculosus fucoidan extract was safe and well tolerated. At a dose of 300 mg, the extract showed no difference in reduction of OA symptoms from the placebo. PMID:27307702

  18. Modelling temporal trends of 137Cs and 99Tc concentrations in Fucus vesiculosus from the eastern Irish coastline.

    PubMed

    Cournane, S; Vintró, L León; Mitchell, P I; McMahon, C A; Smith, K; Long, S

    2011-11-01

    Time series of 137Cs and 99Tc activity concentrations in the brown seaweed Fucus vesiculosus and seawater, gathered at three locations on the eastern Irish coastline during the period 1988-2008, have been modelled using a novel approach incorporating a variable uptake rate in the seaweed. Seasonal variations in the time series, identified using spectral analysis, were incorporated into the model which was used to determine transfer kinetic parameters and to predict 137Cs and 99Tc concentrations in seaweed, as influenced by levels in ambient seawater. An optimisation method combining evolutionary and grid search minimisation techniques was adopted to determine the best values for the model parameters, from which concentration factors (CF) and biological half-lives (tb1/2) for 137Cs and 99Tc in F. vesiculosus were calculated. CF values of 170-179 and 1.1×105 l kg(-1) (dry weight) were obtained for 137Cs and 99Tc, respectively, while the corresponding tb1/2 values were 39-47 and 32 days, respectively.

  19. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis.

    PubMed

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis.

  20. Trends in the spatial and temporal distribution of 129I and 99Tc in coastal waters surrounding Ireland using Fucus vesiculosus as a bio-indicator.

    PubMed

    Keogh, S M; Aldahan, A; Possnert, G; Finegan, P; León Vintró, L; Mitchell, P I

    2007-01-01

    Spatial and temporal trends in (129)I and (99)Tc concentrations around the Irish coastline have been evaluated using Fucus vesiculosus as a bio-indicator. (129)I concentrations in a recent set of seawater samples have also been recorded and reveal an identical spatial pattern. Concentrations of (129)I in Fucus from the northeast coast of Ireland proved to be at least two orders of magnitude higher than concentrations in Fucus from the west coast. The (129)I content of Fucus increased significantly between 1985 and 2003, in line with increases in discharges of (129)I from the Sellafield nuclear reprocessing plant. Similar trends were observed in the case of (99)Tc. (129)I/(99)Tc ratios in Irish seawater were deduced from the Fucus data, and compared to ratios in discharges from Sellafield and from the French reprocessing plant at Cap de la Hague. Levels of (129)I and (99)Tc in Fucus from the west coast were found to be enhanced with respect to levels in seaweeds from other regions in the Northern Hemisphere unaffected by discharges from nuclear installations such as those referred to.

  1. Comparing the relative importance of water-borne cues and direct grazing for the induction of defenses in the brown seaweed Fucus vesiculosus.

    PubMed

    Flöthe, Carla R; John, Uwe; Molis, Markus

    2014-01-01

    Some seaweed species have been shown to release water-borne cues after herbivore attack, for example, to attract natural enemies of the herbivore. These cues may also be sensed by neighboring seaweeds and used to adjust their defenses in anticipation of a possible herbivore attack. Several studies indicated information transfer between seaweed individuals in the past, including the brown seaweed Fucus vesiculosus. Previous work showed induction of defenses in F. vesiculosus in response to water-borne cues released by isopod-grazed conspecifics. In contrast, another study on induced responses after exposure to cues from isopod-grazed neighbors using the same seaweed species yielded contradictory results. This study reassessed the ability of F. vesiculosus individuals to sense water-borne cues released by isopod-grazed neighbors in a series of experiments that monitored F. vesiculosus palatability in response to direct grazing by Idotea baltica and water-borne cues from isopod-grazed neighbors relative to unmanipulated seaweed pieces. Two-choice feeding assays were conducted with both fresh and reconstituted seaweed pieces. Direct grazing by I. baltica induced a chemical defense in F. vesiculosus, confirming results of previous studies. In contrast, evidence for increased herbivore resistance in seaweed pieces that were located downstream of isopod-grazed F. vesiculosus could not be provided. The lack of defense induction in response to grazing of conspecific neighbors may be explained by the environmental conditions and the scattered distribution of F. vesiculosus individuals in the intertidal zone of Helgoland, which may render resource investment in the emission and/or response to water-borne cues at this site unprofitable.

  2. Shift happens: trailing edge contraction associated with recent warming trends threatens a distinct genetic lineage in the marine macroalga Fucus vesiculosus

    PubMed Central

    2013-01-01

    Background Significant effects of recent global climate change have already been observed in a variety of ecosystems, with evidence for shifts in species ranges, but rarely have such consequences been related to the changes in the species genetic pool. The stretch of Atlantic coast between North Africa and North Iberia is ideal for studying the relationship between species distribution and climate change as it includes the distributional limits of a considerable number of both cold- and warm-water species. We compared temporal changes in distribution of the canopy-forming alga Fucus vesiculosus with historical sea surface temperature (SST) patterns to draw links between range shifts and contemporary climate change. Moreover, we genetically characterized with microsatellite markers previously sampled extinct and extant populations in order to estimate resulting cryptic genetic erosion. Results Over the past 30 years, a geographic contraction of the southern range edge of this species has occurred, with a northward latitudinal shift of approximately 1,250 km. Additionally, a more restricted distributional decline was recorded in the Bay of Biscay. Coastal SST warming data over the last three decades revealed a significant increase in temperature along most of the studied coastline, averaging 0.214°C/decade. Importantly, the analysis of existing and extinct population samples clearly distinguished two genetically different groups, a northern and a southern clade. Because of the range contraction, the southern group is currently represented by very few extant populations. This southern edge range shift is thus causing the loss of a distinct component of the species genetic background. Conclusions We reveal a climate-correlated diversity loss below the species level, a process that could render the species more vulnerable to future environmental changes and affect its evolutionary potential. This is a remarkable case of genetic uniqueness of a vanishing cryptic genetic

  3. Isolation and partial characterization of a novel amino sugar-containing fucan sulfate from commercial Fucus vesiculosus fucoidan.

    PubMed

    Nishino, T; Nishioka, C; Ura, H; Nagumo, T

    1994-03-04

    Commercial crude fucoidan (Sigma) from the brown seaweed Fucus vesiculosus was fractionated into its polysaccharide components by gel filtration and anion-exchange chromatography to clarify the structure-anticoagulant activity relationship. The products comprised a wide spectrum of fucans ranging from typical fucoidans (major components) containing mainly fucose, sulfate, and no uronic acid to low sulfate-containing heteropolysaccharide-like fucans (minor components) being composed of neutral sugars other than fucose and a high content of uronic acid(s). The polysaccharide components also had a wide range of molecular weight. The typical fucoidans showed a potent anticoagulant activity, whereas the other fucans had no or only slight activity. One of the fractions found as a minor component, was a novel polysaccharide containing an appreciable amount (11.5%) of glucosamine and a small amount (5.2%) of protein in addition to fucose and sulfate, and having a low apparent molecular weight of 6800. This is the first report that a proteoglycan-like, amino sugar-containing fucan sulfate, composed of fucose, galactose, glucose, mannose, xylose, uronic acid, glucosamine, and sulfate in the molar ratio of 1.00:0.04:0.01:0.48:0.24:0.18:0.56:1.90, could be obtained from brown seaweed. However, this polysaccharide showed no anticoagulant activity.

  4. Fucoidan extracted from Fucus evanescens brown algae corrects immunity and hemostasis disorders in experimental endotoxemia.

    PubMed

    Kuznetsova, T A

    2009-01-01

    Fucoidan extracted from brown algae (Fucus evanescens) was used for correction of immunity and hemostasis disorders in experimental endotoxemia induced by injection of LPS. Fucoidan reduced the elevated levels of proinflammatory cytokines (TNF-alpha, IL-1, IL-6) and partially arrested hypercoagulation phenomena, thus improving animal resistance to LPS.

  5. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis

    PubMed Central

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis. PMID:27035150

  6. The impact of ocean acidification and warming on the elemental and stable isotope composition of Fucus vesiculosus in Wadden Sea mesocosm studies

    NASA Astrophysics Data System (ADS)

    Winde, Vera; Pansch, Andreas; Fenner, Anna-Kathrina; Voss, Maren; Schmiedinger, Iris; Schneider, Bernd; Asmus, Ragnhild; Asmus, Harald; Böttcher, Michael E.

    2015-04-01

    In the frame of the German BIOACID II project the separate and combined effects of different stress factors (acidification, warming, eutrophication) on the elemental and stable isotope composition of Fucus vesiculosus are investigated by means of benthic mesocosm experiments in coastal waters of the the North Sea. We aim for a calibration of the biogeochemical and stable isotope composition of Fucus in response to single and combined temperature, pCO2 (pH), and nutrient changes. Benthocosm experiments are carried out at the AWI Wadden Sea station in List (Sylt Island, North Sea) with application of different stressors: an increase in temperature and an increase in atmospheric CO2 partial pressure. The experiments run for almost several months per season. The aquatic biogeochemistry (e.g. TA, pH, 13C(DIC)) as well as the elemental and stable isotope composition of the grown Fucus vesiculosus organic tissue were followed. It was found, that the changes in daily biological activity caused by alternating phases of net respiration and photosynthesis created strong variations in the dissolved carbonate system and changes in the carbon isotope composition of DIC. The atmosphere of some experimental set-ups was enriched with gaseous carbon dioxide. This caused fast corresponding changes in the isotopic composition of DIC, thereby acting as a tracer for newly formed organic tissue. The chemical and isotopic parameters of the dissolved carbonate system showed differences between the set ups. The research is supported by BMBF during project BIOACID II, Helmholtz AWI Sylt, and Leibniz IOW

  7. Nutrient availability modifies species abundance and community structure of Fucus-associated littoral benthic fauna.

    PubMed

    Korpinen, Samuli; Jormalainen, Veijo; Pettay, Esko

    2010-01-01

    The brown alga Fucus vesiculosus is a foundation species in the Baltic Sea littoral, hosting a rich faunal community. We compared the species composition and diversity of invertebrate macrofauna living on F. vesiculosus between sites differing in their eutrophication status and exposure to waves at three different times during a season. We determined the size, nitrogen and phlorotannin content of the alga. The invertebrate community differed substantially between sites near fish farms and those in more pristine environment. Snails and bivalves were more abundant on the Fucus stands near fish farms than on control stands, where crustaceans were more abundant. The abundance of molluscs decreased with the increasing shore exposure, while gammaridean amphipods dominated on the exposed shores. Abundance of several taxa increased during the proceeding growing season. The density of the most important herbivore of F. vesiculosus, Idotea balthica, varied 100-fold during the season being the lowest in June and the highest in August when the generation born in the summer started to feed on Fucus. Thus, the diversity and composition of Fucus-associated invertebrate fauna varies both with environmental conditions of the stand and seasonally. Although the negative effects of eutrophication on distribution and abundance of Fucus stands are well documented, a moderate increase of nutrients was found to increase the species richness of Fucus-associated fauna in early summer.

  8. Modelling the biological half-life and seasonality of ¹⁴C in Fucus vesiculosus from the east coast of Ireland: implications for the estimation of future trends.

    PubMed

    Keogh, S M; Cournane, S; León Vintró, L; McGee, E J; Mitchell, P I

    2011-04-01

    Radiocarbon levels were recorded in Fucus vesiculosus samples collected on a monthly basis over a three-year period at a site on the east coast of Ireland. The resulting data was analysed using a numerical model which estimates the transit times from the Sellafield plant to the sampling location, and the mean availability time of ¹⁴C in seaweed. With the inclusion of a model parameter allowing for seasonal variability in uptake by the Fucus, good correlation was observed between the predicted and measured concentrations. Future temporal trends of ¹⁴C Fucus concentrations along the eastern Irish coastline were modelled with the application of three possible prospective discharge scenarios, predicting ¹⁴C Fucus concentrations to reduce to ambient background levels within 2.5-years of discharges being set to zero. Such projections may prove helpful in assessing the consequences of discharge management and policy making in the context of the OSPAR convention.

  9. Protective effect of fucoidan from Fucus vesiculosus on liver fibrosis via the TGF-β1/Smad pathway-mediated inhibition of extracellular matrix and autophagy

    PubMed Central

    Li, Jingjing; Chen, Kan; Li, Sainan; Feng, Jiao; Liu, Tong; Wang, Fan; Zhang, Rong; Xu, Shizan; Zhou, Yuqing; Zhou, Shunfeng; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    Liver fibrosis is a dynamic reversible pathological process in the development of chronic liver disease to cirrhosis. However, the current treatments are not administered for a long term due to their various side effects. Autophagy is initiated to decompose damaged or excess organelles, which had been found to alter the progression of liver fibrosis. In this article, we hypothesized that fucoidan from Fucus vesiculosus may attenuate liver fibrosis in mice by inhibition of the extracellular matrix and autophagy in carbon tetrachloride- and bile duct ligation-induced animal models of liver fibrosis. The results were determined using enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemical staining. Fucoidan from F. vesiculosus could inhibit the activation of hepatic stellate cells and the formation of extracellular matrix and autophagosomes, and its effect may be associated with the downregulation of transforming growth factor beta 1/Smads pathways. Fucoidan, as an autophagy and transforming growth factor beta 1 inhibitor, could be a promising potential therapeutic agent for liver fibrosis. PMID:26929597

  10. Bioaccumulation of Hg, Cd and Pb by Fucus vesiculosus in single and multi-metal contamination scenarios and its effect on growth rate.

    PubMed

    Henriques, Bruno; Lopes, Cláudia B; Figueira, Paula; Rocha, Luciana S; Duarte, Armando C; Vale, Carlos; Pardal, Miguel A; Pereira, Eduarda

    2017-03-01

    Results of 7-days exposure to metals, using environmentally realistic conditions, evidenced the high potential of living Fucus vesiculosus to remove Pb, Hg and Cd from contaminated salt waters. For different contamination scenarios (single- and multi-contamination), ca 450 mg L(-1) (dry weight), enable to reduce the concentrations of Pb in 65%, of Hg in 95% and of Cd between 25 and 76%. Overall, bioconcentration factors ranged from 600 to 2300. Elovich kinetic model described very well the bioaccumulation of Pb and Cd over time, while pseudo-second-order model adjusted better to experimental data regarding Hg. F. vesiculosus showed different affinity toward studied metals, following the sequence order: Hg > Pb > Cd. Analysis of metal content in the macroalgae after bioaccumulation, proved that all metal removed from solution was bound to the biomass. Depuration experiments reveled no significant loss of metal back to solution. Exposure to contaminants only adversely affected the organism's growth for the highest concentrations of Cd and Pb. Findings are an important contribute for the development of remediation biotechnologies for confined saline waters contaminated with trace metal contaminants, more efficient and with lower costs than the traditional treatment methods.

  11. Protective effect of fucoidan from Fucus vesiculosus on liver fibrosis via the TGF-β1/Smad pathway-mediated inhibition of extracellular matrix and autophagy.

    PubMed

    Li, Jingjing; Chen, Kan; Li, Sainan; Feng, Jiao; Liu, Tong; Wang, Fan; Zhang, Rong; Xu, Shizan; Zhou, Yuqing; Zhou, Shunfeng; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    Liver fibrosis is a dynamic reversible pathological process in the development of chronic liver disease to cirrhosis. However, the current treatments are not administered for a long term due to their various side effects. Autophagy is initiated to decompose damaged or excess organelles, which had been found to alter the progression of liver fibrosis. In this article, we hypothesized that fucoidan from Fucus vesiculosus may attenuate liver fibrosis in mice by inhibition of the extracellular matrix and autophagy in carbon tetrachloride- and bile duct ligation-induced animal models of liver fibrosis. The results were determined using enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemical staining. Fucoidan from F. vesiculosus could inhibit the activation of hepatic stellate cells and the formation of extracellular matrix and autophagosomes, and its effect may be associated with the downregulation of transforming growth factor beta 1/Smads pathways. Fucoidan, as an autophagy and transforming growth factor beta 1 inhibitor, could be a promising potential therapeutic agent for liver fibrosis.

  12. Induced resistance to periwinkle grazing in the brown seaweed Fucus vesiculosus (Phaeophyceae): molecular insights and seaweed-mediated effects on herbivore interactions.

    PubMed

    Flöthe, Carla R; Molis, Markus; John, Uwe

    2014-06-01

    Herbivory is a key factor for controlling seaweed biomass and community structure. To cope with grazers, constitutive and inducible defenses have evolved in macroalgae. Inducible chemical defenses show grazer-specificity and, at the same time, have the potential to mediate interactions among different herbivores. Furthermore, temporal variations in defense patterns, which may adjust antiherbivory responses to grazing pressure, were reported in two brown seaweeds. However, underlying cellular processes are only rudimentarily characterized. To investigate the response of Fucus vesiculosus (L.) to periwinkle (Littorina obtusata) grazing, feeding assays were conducted at several times during a 33 d induction experiment. Underlying cellular processes were analyzed through gene expression profiling. Furthermore, direct processes driving the antiherbivory response to periwinkle grazing and indirect effects on another herbivore, the isopod Idotea baltica, were elucidated. F. vesiculosus showed multiple defense pulses in response to periwinkle grazing, suggesting a high level of temporal variability in antiherbivory traits. Defense induction was accompanied by extensive transcriptome changes. Approximately 400 genes were significantly up-/down-regulated relative to controls, including genes relevant for translation and the cytoskeleton. Genes involved in photosynthesis were mostly down-regulated, while genes related to the respiratory chain were up-regulated, indicating alterations in resource allocation. The comparison of genes regulated in response to isopod (previous study) and periwinkle grazing suggests specific induction of several genes by each herbivore. However, grazing by both herbivores induced similar metabolic processes in F. vesiculosus. These common defense-related processes reflected in strong indirect effects as isopods were also repelled after previous grazing by L. obtusata.

  13. Evolution and diversification within the intertidal brown macroalgae Fucus spiralis/F. vesiculosus species complex in the North Atlantic.

    PubMed

    Coyer, J A; Hoarau, G; Costa, J F; Hogerdijk, B; Serrão, E A; Billard, E; Valero, M; Pearson, G A; Olsen, J L

    2011-02-01

    We examined 733 individuals of Fucusspiralis from 21 locations and 1093 Fucusvesiculosus individuals from 37 locations throughout their northern hemisphere ranges using nuclear and mitochondrial markers. Three genetic entities of F. spiralis were recovered. In northern and sympatric populations, the presence of "F. spiralis Low" in the mid-intertidal and "F. spiralis High" in the high-intertidal was confirmed and both co-occurred with the sister species F. vesiculosus. The third and newly-discovered entity, "F. spiralis South", was present mainly in the southern range, where it did not co-occur with F. vesiculosus. The South entity diverged early in allopatry, then hybridized with F. vesiculosus in sympatry to produce F. spiralis Low. Ongoing parallel evolution of F. spiralis Low and F. spiralis High is most likely due to habitat preference/local selection and maintained by preferentially selfing reproductive strategies. Contemporary populations of F. spiralis throughout the North Atlantic stem from a glacial refugium around Brittany involving F. spiralis High; F. spiralis South was probably unaffected by glacial episodes. Exponential population expansion for F. vesiculosus began during the Cromer and/Holstein interglacial period (300,000-200,000 yrs BP). Following the last glacial maximum (30,000-22,000 yrs BP), a single mtDNA haplotype from a glacial refugium in SW Ireland colonized Scandinavia, the Central Atlantic islands, and the W Atlantic.

  14. Buffering and Amplifying Interactions among OAW (Ocean Acidification & Warming) and Nutrient Enrichment on Early Life-Stage Fucus vesiculosus L. (Phaeophyceae) and Their Carry Over Effects to Hypoxia Impact

    PubMed Central

    Al-Janabi, Balsam; Kruse, Inken; Graiff, Angelika; Winde, Vera; Lenz, Mark; Wahl, Martin

    2016-01-01

    Ocean acidification and warming (OAW) are occurring globally. Additionally, at a more local scale the spreading of hypoxic conditions is promoted by eutrophication and warming. In the semi-enclosed brackish Baltic Sea, occasional upwelling in late summer and autumn may expose even shallow-water communities including the macroalga Fucus vesiculosus to particularly acidified, nutrient-rich and oxygen-poor water bodies. During summer 2014 (July–September) sibling groups of early life-stage F. vesiculosus were exposed to OAW in the presence and absence of enhanced nutrient levels and, subsequently to a single upwelling event in a near-natural scenario which included all environmental fluctuations in the Kiel Fjord, southwestern Baltic Sea, Germany (54°27 ´N, 10°11 ´W). We strove to elucidate the single and combined impacts of these potential stressors, and how stress sensitivity varies among genetically different sibling groups. Enhanced by a circumstantial natural heat wave, warming and acidification increased mortalities and reduced growth in F. vesiculosus germlings. This impact, however, was mitigated by enhanced nutrient conditions. Survival under OAW conditions strongly varied among sibling groups hinting at a substantial adaptive potential of the natural Fucus populations in the Western Baltic. A three-day experimental upwelling caused severe mortality of Fucus germlings, which was substantially more severe in those sibling groups which previously had been exposed to OAW. Our results show that global (OAW), regional (nutrient enrichment) and local pressures (upwelling), both alone and co-occurring may have synergistic and antagonistic effects on survival and/or growth of Fucus germlings. This result emphasizes the need to consider combined stress effects. PMID:27043710

  15. Buffering and Amplifying Interactions among OAW (Ocean Acidification & Warming) and Nutrient Enrichment on Early Life-Stage Fucus vesiculosus L. (Phaeophyceae) and Their Carry Over Effects to Hypoxia Impact.

    PubMed

    Al-Janabi, Balsam; Kruse, Inken; Graiff, Angelika; Winde, Vera; Lenz, Mark; Wahl, Martin

    2016-01-01

    Ocean acidification and warming (OAW) are occurring globally. Additionally, at a more local scale the spreading of hypoxic conditions is promoted by eutrophication and warming. In the semi-enclosed brackish Baltic Sea, occasional upwelling in late summer and autumn may expose even shallow-water communities including the macroalga Fucus vesiculosus to particularly acidified, nutrient-rich and oxygen-poor water bodies. During summer 2014 (July-September) sibling groups of early life-stage F. vesiculosus were exposed to OAW in the presence and absence of enhanced nutrient levels and, subsequently to a single upwelling event in a near-natural scenario which included all environmental fluctuations in the Kiel Fjord, southwestern Baltic Sea, Germany (54°27 ´N, 10°11 ´W). We strove to elucidate the single and combined impacts of these potential stressors, and how stress sensitivity varies among genetically different sibling groups. Enhanced by a circumstantial natural heat wave, warming and acidification increased mortalities and reduced growth in F. vesiculosus germlings. This impact, however, was mitigated by enhanced nutrient conditions. Survival under OAW conditions strongly varied among sibling groups hinting at a substantial adaptive potential of the natural Fucus populations in the Western Baltic. A three-day experimental upwelling caused severe mortality of Fucus germlings, which was substantially more severe in those sibling groups which previously had been exposed to OAW. Our results show that global (OAW), regional (nutrient enrichment) and local pressures (upwelling), both alone and co-occurring may have synergistic and antagonistic effects on survival and/or growth of Fucus germlings. This result emphasizes the need to consider combined stress effects.

  16. Influence of releases of (129)I and (137)Cs from European reprocessing facilities in Fucus vesiculosus and seawater from the Kattegat and Skagerrak areas.

    PubMed

    Gómez-Guzmán, J M; Holm, E; Niagolova, N; López-Gutiérrez, J M; Pinto-Gómez, A R; Abril, J A; García-León, M

    2014-08-01

    (129)I is a very long-lived radionuclide (T1/2=15.7×10(6) years) that is present in the environment because of natural and anthropogenic sources. Compared to the pre-nuclear era, large amounts of (129)I have been released to the marine environment, especially as liquid and gaseous discharges from two European reprocessing facilities located at Sellafield (England) and La Hague (France). The marine environment, i.e., the oceans, is the major source of iodine. Brown seaweed accumulates iodine at high levels up to 1.0% of dry weigh, and therefore they are ideal bioindicators for studying levels of (129)I. In this work, (129)I concentrations have been determined in seaweed Fucus vesiculosus and seawater collected in the Kattegat and Skagerrak areas in July 2007. The resulting data were evaluated in terms of (129)I concentrations and (129)I/(137)Cs ratios. (129)I concentrations were found to be in the order of (44-575)×10(9) atoms g(-1) in seaweed and (5.4-51)×10(9) atoms g(-1) in seawater, with an enhancement in the Skagerrak area in comparison to the Kattegat area. Iodine-129 concentrations in both seaweed and seawater were used to determine the concentration factor of iodine in brown seaweed F. vesiculosus. The high levels of (129)I and (129)I/(137)Cs ratios in the Skagerrak area and their gradually decreasing trend to the Kattegat indicates that the most important contribution to the (129)I inventory in those areas comes from Sellafield and La Hague reprocessing plants.

  17. Pre- and post-Chernobyl accident levels of 129I and 137Cs in the Southern Baltic Sea by brown seaweed Fucus vesiculosus.

    PubMed

    Gómez-Guzmán, J M; Holm, E; Enamorado-Báez, S M; Abril, J A; Pinto-Gómez, A R; López-Gutiérrez, J M; García-León, M

    2013-01-01

    (129)I is a very long-lived radionuclide (T(1/2) = 15.7 × 10(6) years) that is present in the environment both because of natural and anthropogenic sources. In this work (129)I concentration and (129)I/(127)I ratio have been determined in seaweed Fucus vesiculosus collected in the Southern Baltic Sea during 1982 and 1986 (post-Chernobyl accident). The resulting data were evaluated in terms of (129)I concentrations, (129)I/(127)I and (129)I/(137)Cs ratios. (129)I concentrations were found to be in the order of (0.82-5.89) × 10(9) atoms g(-1) in 1982 and (1.33-38.83) × 10(9) atoms g(-1) in 1986. The (129)I/(127)I ratios ranged from (22.7-87.8) × 10(-10) for seaweed collected in 1982 and from (26.1-305.5) × 10(-10) for seaweed collected in 1986. Also a linear relationship was established for (127)I concentrations in seawater and salinity in this area, enabling the estimation of concentration factors for (127)I in F. vesiculosus. The high levels of (129)I and (129)I/(127)I in the Kattegat and their gradually decreasing trend to the Baltic Sea indicates that the most important contribution to the (129)I inventory in the Baltic Sea area comes from Sellafield and La Hague reprocessing plants. With respect to Chernobyl accident, (129)I concentrations in samples collected in 1986 were not much higher than those expected in less contaminated samples from 1982. This supports the view that the contribution of the Chernobyl accident to (129)I in the Baltic region was not significant.

  18. An antithrombotic fucoidan, unlike heparin, does not prolong bleeding time in a murine arterial thrombosis model: a comparative study of Undaria pinnatifida sporophylls and Fucus vesiculosus.

    PubMed

    Min, Soon-Ki; Kwon, Oh-Choon; Lee, Sub; Park, Ki-Hyuk; Kim, Jong-Ki

    2012-05-01

    The antithrombotic activities and bleeding effects of selected fucoidans (source from either Undaria pinnatifida sporophylls or from Fucus vesiculosus) have been compared with heparin in the ferric chloride-induced arterial thrombus mouse model. Thrombosis was induced by applying 5% ferric chloride for 3 min on the carotid artery region of Balb/c mouse. Five minutes prior to thrombus induction, mice were infused through the tail vein with either saline (control) or polysaccharides. Either fucoidan or heparin was dosed at 0.1, 1.25, 2.5, 5.0, 10, 25, or 50 mg/kg intravenously (i.v.) The carotid blood flow was monitored until more than 60 min post-thrombus induction. Mouse tail transection bleeding time was measured up to 60 min after making a cut in the mouse tail. Both antithrombotic and bleeding effects were observed in a dose-dependent manner for both fucoidans and heparin. Thrombus formation was totally (reflected by Doppler flow meter) inhibited at either 5 or 50 mg/kg of unfractionated Undaria fucoidan or a low-molecular-weight Undaria fucoidan fraction, respectively, without prolonging the time-to-stop bleeding compared with the control (p < 0.01). The total inhibition of thrombus formation was observed for unfractionated Fucus fucoidan at 25 mg/kg where the time-to-stop bleeding was still significantly prolonged, by as much as 8 ± 1.7 min (p < 0.02). In contrast the heparin-treated group showed total inhibition of thrombus formation even at a small dose of 0.8 mg/kg (400 IU) at which bleeding continued until 60 min. In conclusion algal fucoidans are highly antithrombotic without potential haemorrhagic effects compared with heparin in the arterial thrombus model, but this property differs from algal species to species, and from the molecular structure of fucoidans.

  19. Chemotactic movement in sperm of the oogamous brown algae, Saccharina japonica and Fucus distichus.

    PubMed

    Kinoshita, Nana; Nagasato, Chikako; Motomura, Taizo

    2017-01-01

    In oogamous species of brown algae such as Saccharina japonica and Fucus distichus, the sperm possess an unusual long posterior flagellum, which oscillates actively and produces a propulsive force during swimming. In this study, we quantitatively analyzed the effect of chemotactic responses on sperm swimming and flagellar waveforms by high-speed video recordings. We found that the thigmotactic response to the chemo-attractant was not enhanced during chemotactic swimming and that the swimming velocity of sperm did not decrease. As concentration of the chemo-attractant decreased, the sperm performed drastic U-turn movements, which was caused by a rapid and large bend of the posterior flagellum. Unilateral bending of the posterior flagellum when sensing a decrease in the concentration of the chemo-attractant may be a common response in male gametes during fertilization of brown algae both oogamous and isogamous species.

  20. Fucoidan from Sargassum sp. and Fucus vesiculosus reduces cell viability of lung carcinoma and melanoma cells in vitro and activates natural killer cells in mice in vivo.

    PubMed

    Ale, Marcel Tutor; Maruyama, Hiroko; Tamauchi, Hidekazu; Mikkelsen, Jørn D; Meyer, Anne S

    2011-10-01

    Fucoidan is known to exhibit crucial biological activities, including anti-tumor activity. In this study, we examined the influence of crude fucoidan extracted from Sargassum sp. (MTA) and Fucus vesiculosus (SIG) on Lewis lung carcinoma cells (LCC) and melanoma B16 cells (MC). In vitro studies were performed using cell viability analysis and showed that SIG and MTA fucoidans significantly decreased the viable number of LCC and MC cells in a dose-response fashion. Histochemical staining showed morphological changes of melanoma B16 cells after exposure to fucoidan. The observed changes were indicative of crude fucoidan induced apoptosis. Male C57BL/6JJCL mice were subjected to daily i.p. injections over 4 days with either SIG or MTA fucoidan (50mg/kg body wt.). The cytolytic activity of natural killer (NK) cells was enhanced by crude fucoidan in a dose-dependent manner as indicated by (51)Cr labeled YAC-1 target cell release. This study provides substantial indications that crude fucoidan exerts bioactive effects on lung and skin cancer model cells in vitro and induces enhanced natural killer cell activity in mice in vivo.

  1. Restructuring of Epibacterial Communities on Fucus vesiculosus forma mytili in Response to Elevated pCO2 and Increased Temperature Levels.

    PubMed

    Mensch, Birte; Neulinger, Sven C; Graiff, Angelika; Pansch, Andreas; Künzel, Sven; Fischer, Martin A; Schmitz, Ruth A

    2016-01-01

    Marine multicellular organisms in composition with their associated microbiota-representing metaorganisms-are confronted with constantly changing environmental conditions. In 2110, the seawater temperature is predicted to be increased by ~5°C, and the atmospheric carbon dioxide partial pressure (pCO2) is expected to reach approximately 1000 ppm. In order to assess the response of marine metaorganisms to global changes, e.g., by effects on host-microbe interactions, we evaluated the response of epibacterial communities associated with Fucus vesiculosus forma mytili (F. mytili) to future climate conditions. During an 11-week lasting mesocosm experiment on the island of Sylt (Germany) in spring 2014, North Sea F. mytili individuals were exposed to elevated pCO2 (1000 ppm) and increased temperature levels (Δ+5°C). Both abiotic factors were tested for single and combined effects on the epibacterial community composition over time, with three replicates per treatment. The respective community structures of bacterial consortia associated to the surface of F. mytili were analyzed by Illumina MiSeq 16S rDNA amplicon sequencing after 0, 4, 8, and 11 weeks of treatment (in total 96 samples). The results demonstrated that the epibacterial community structure was strongly affected by temperature, but only weakly by elevated pCO2. No interaction effect of both factors was observed in the combined treatment. We identified several indicator operational taxonomic units (iOTUs) that were strongly influenced by the respective experimental factors. An OTU association network analysis revealed that relationships between OTUs were mainly governed by habitat. Overall, this study contributes to a better understanding of how epibacterial communities associated with F. mytili may adapt to future changes in seawater acidity and temperature, ultimately with potential consequences for host-microbe interactions.

  2. Restructuring of Epibacterial Communities on Fucus vesiculosus forma mytili in Response to Elevated pCO2 and Increased Temperature Levels

    PubMed Central

    Mensch, Birte; Neulinger, Sven C.; Graiff, Angelika; Pansch, Andreas; Künzel, Sven; Fischer, Martin A.; Schmitz, Ruth A.

    2016-01-01

    Marine multicellular organisms in composition with their associated microbiota—representing metaorganisms—are confronted with constantly changing environmental conditions. In 2110, the seawater temperature is predicted to be increased by ~5°C, and the atmospheric carbon dioxide partial pressure (pCO2) is expected to reach approximately 1000 ppm. In order to assess the response of marine metaorganisms to global changes, e.g., by effects on host-microbe interactions, we evaluated the response of epibacterial communities associated with Fucus vesiculosus forma mytili (F. mytili) to future climate conditions. During an 11-week lasting mesocosm experiment on the island of Sylt (Germany) in spring 2014, North Sea F. mytili individuals were exposed to elevated pCO2 (1000 ppm) and increased temperature levels (Δ+5°C). Both abiotic factors were tested for single and combined effects on the epibacterial community composition over time, with three replicates per treatment. The respective community structures of bacterial consortia associated to the surface of F. mytili were analyzed by Illumina MiSeq 16S rDNA amplicon sequencing after 0, 4, 8, and 11 weeks of treatment (in total 96 samples). The results demonstrated that the epibacterial community structure was strongly affected by temperature, but only weakly by elevated pCO2. No interaction effect of both factors was observed in the combined treatment. We identified several indicator operational taxonomic units (iOTUs) that were strongly influenced by the respective experimental factors. An OTU association network analysis revealed that relationships between OTUs were mainly governed by habitat. Overall, this study contributes to a better understanding of how epibacterial communities associated with F. mytili may adapt to future changes in seawater acidity and temperature, ultimately with potential consequences for host-microbe interactions. PMID:27065988

  3. [EFFECT OF FUCOIDANS ISOLATED FROM SEAWEEDS LAMINARIA DIGITATA AND FUCUS VESICULOSUS ON CELL LINES HELA G-63, ECV 304 AND PC 12].

    PubMed

    Zhurishkina, E V; Lapina, I M; Ivanen, D R; Stepanov, S I; Shvetsova, S V; Shavarda, A L; Giliano, N Ya; Kulminskaya, A A

    2015-01-01

    The aim of the research was to investigate cytotoxicity of fucoidans on mammals cells. Three different samples of fucoidans were isolated from mechanically grounded brown algae Laminaria digitata and Fucus ve- siculosus. The sample F2 that differed from the others by higher sulfatation level and suppression of HeLa G-63 line culture growth was taken for further study in cell lines HeLa G-63, ECV 304 and PC 12. We have shown that fucoidan preparation F2 inhibits proliferation and induces cell death in a dose- and time-dependent manner for all investigated cell lines. Neuroendocrine tumor rat cell line PC 12 appeared to be the most sensitive to fucoidan treatment whereas endothelial human cells ECV 304 were the least sensitive.

  4. Does thalli complexity and biomass affect the associated flora and fauna of two co-occurring Fucus species in the Baltic Sea?

    NASA Astrophysics Data System (ADS)

    Schagerström, Ellen; Forslund, Helena; Kautsky, Lena; Pärnoja, Merli; Kotta, Jonne

    2014-08-01

    On rocky shores, fucoids provide habitat, shelter and food for associated biota. In the northern parts of the Baltic, the Bothnian Sea, the new fucoid species Fucus radicans (Bergström et Kautsky) was recently described. This study compares the thallus complexity and size as well as quantified the abundance and biomass of epiphytic algae and invertebrate taxa of the two fucoid species F. radicans and Fucus vesiculosus L. from sympatric sites in the Bothnian Sea on the Swedish coast and around the Estonian island Saaremaa. We found that F. radicans was more complex than F. vesiculosus within the whole study range, but both species had a more complex thallus structure in the Bothnian Sea compared to Estonia. The complexity of host algae did not contribute to their associated flora and fauna taxon richness; instead, the size of thalli was a good proxy for associated communities. Specifically, on a biomass basis, F. vesiculosus displayed highest species richness and highest faunal abundance in the Bothnian Sea, whereas no such differences were found around Saaremaa, probably because both Fucus species had similar height around Saaremaa whereas F. vesiculosus grew much taller and larger in the Bothnian Sea. There were some unique associated macroalgal and invertebrate species that were found only on either of the fucoids, indicating the importance of separating them as species in surveys and monitoring.

  5. Aryl sulfate formation in sea urchins (Strongylocentrotus droebachiensis) ingesting marine algae (Fucus distichus) containing 2,6-dimethylnapthalene

    SciTech Connect

    Malins, D.C.; Roubal, W.T.

    1982-04-01

    The metabolism of tritiated 2,6-dimethylnapthalene (2,6-DMN) was studied in sea urchins (Strongylocentrotus droebachiensis) feeding on marine algae (Fucus distichus). The Fucus accumulated this hydrocarbon from sea water without converting it to metabolites. Most of the tritium accumulated by the sea urchins (e.g., 70.8% after 3 days) from feeding on 2,6-DMN-exposed Fucus was present in the exoskeleton (shell and spines). Moreover, after 3 days feeding, about 90% of the tritium in the total metabolite fraction of the gonads and digestive tract of the sea urchin was present as sulfate derivatives. These metabolites were identified through hydrolysis with aryl sulfatase, followed by thin-layer chromatography of the products. After 14 days of feeding, the tritium associated with the sulfate derivatives decreased in the gonads and digestive tract to 61 and 65%, respectively, of the total metabolite fraction. Hydroxy compounds from sulfatase hydrolysis were chromatographed using multiple elutions with toluene. The hydroxy isomers were separated and the R/sub f/ values were compared to those of pure reference compounds. The data indicated that 80% of the 2,6-dimethylnaphtyl sulfate contained the sulfate on the 1 and/or 3 position of the aromatic ring. Moreover, 6-methyl-2-naphthalenemethanol was not detected, which implies that sea urchins, unlike fish, metabolize alkyl-substituted aromatic hydrocarbons primarily through aromatic ring oxidations.

  6. Osmium uptake, distribution, and 187Os/188Os and 187Re/188Os compositions in Phaeophyceae macroalgae, Fucus vesiculosus: Implications for determining the 187Os/188Os composition of seawater

    NASA Astrophysics Data System (ADS)

    Racionero-Gómez, B.; Sproson, A. D.; Selby, D.; Gannoun, A.; Gröcke, D. R.; Greenwell, H. C.; Burton, K. W.

    2017-02-01

    The osmium isotopic composition (187Os/188Os) of seawater reflects the balance of input from mantle-, continental- and anthropogenic-derived sources. This study utilizes the Phaeophyceae, Fucus vesiculosus, to analyse its Os abundance and uptake, as well as to assess if macroalgae records the Os isotope composition of the seawater in which it lives. The data demonstrates that Os is not located in one specific biological structure within macroalgae, but is found throughout the organism. Osmium uptake was measured by culturing F. vesiculosus non-fertile tips with different concentrations of Os with a known 187Os/188Os composition (∼0.16), which is significantly different from the background isotopic composition of local seawater (∼0.94). The Os abundance of cultured non-fertile tips show a positive correlation to the concentration of the Os doped seawater. Moreover, the 187Os/188Os composition of the seaweed equalled that of the culture medium, strongly confirming the possible use of macroalgae as a biological proxy for the Os isotopic composition of the seawater.

  7. The invasion of the intertidal canopy-forming alga Fucus serratus L. to southwestern Iceland: Possible community effects

    NASA Astrophysics Data System (ADS)

    Ingólfsson, Agnar

    2008-04-01

    The intertidal serrated wrack, Fucus serratus L. (Fucales: Phaeophyceae), has become an abundant canopy-forming alga along a ca. 100 km stretch of shore in southwestern Iceland in the last century. Its distribution has not changed noticeably since a survey in 1975/1976. Many experimental studies have shown that canopy-forming algae can have profound effects on the community structure. Although such experiments involving F. serratus are few it was decided to test predictions from these experiments on a geographical scale by comparing community compositions within the area where F. serratus is a dominant algae (since at least 1975/1976) with an adjacent area of similar size where F. serratus is absent (with a single exception without consequences). The work is based on measurements on some 372 stations in the F. serratus area, termed region A, and 227 stations from the F. serratus-free area, termed region B. Percentage cover of algae and sessile invertebrates was estimated on 2 m 2 on each station and animals collected from 800 cm 2 from each station. The vertical distribution of F. serratus was most similar to that of Fucus distichus and the two species often grew intermingled on the lower part of the shore. F. serratus appeared to have reduced the cover of F. distichus in the lowermost part of the shore, while having little or no effect on other canopy-forming species. The low abundance of Semibalanus balanoides in the F. serratus area (region A) is in line with experiments showing detrimental effect on this barnacle by whiplash of F. serratus. In general algal grazers were more abundant in region A, consistent with the greater attractiveness of F. serratus than other canopy-forming species to grazers, although this may be partly explained by the abundance of understorey algae in region A.

  8. Toxic effects of decomposing red algae on littoral organisms

    NASA Astrophysics Data System (ADS)

    Eklund, Britta; Svensson, Andreas P.; Jonsson, Conny; Malm, Torleif

    2005-03-01

    Large masses of filamentous red algae of the genera Polysiphonia, Rhodomela, and Ceramium are regularly washed up on beaches of the central Baltic Sea. As the algal masses start to decay, red coloured effluents leak into the water, and this tinge may be traced several hundred meters off shore. In this study, possible toxic effects of these effluents were tested on littoral organisms from different trophic levels. Effects on fertilisation, germination and juvenile survival of the brown seaweed Fucus vesiculosus were investigated, and mortality tests were performed on the crustaceans Artemia salina and Idotea baltica, as well as on larvae and adults of the fish Pomatoschistus microps. Fucus vesiculosus was the most sensitive species of the tested organisms to the red algal extract. The survival of F. vesiculosus recruits was reduced with 50% (LC50) when exposed to a concentration corresponding to 1.7 g l -1 dw red algae. The lethal concentration for I. baltica, A. salina and P. microps were approximately ten times higher. The toxicity to A. salina was reduced if the algal extract was left to decompose during two weeks but the decline in toxicity was not affected by different light or temperature conditions. This study indicates that the filamentous red algae in the central Baltic Sea may produce and release compounds with negative effects on the littoral ecosystem. The effects may be particularly serious for the key species F. vesiculosus, which reproduce in autumn when filamentous red algal blooms are most severe.

  9. Investigation of a sulfate transfer during autohydrolysis of a fucoidan from the brown alga Fucus evanescens by tandem ESIMS.

    PubMed

    Anastyuk, Stanislav D; Shevchenko, Natalia M; Dmitrenok, Pavel S; Zvyagintseva, Tatyana N

    2011-12-27

    A fucoidan from the brown alga Fucus evanescens was effectively depolymerized by autohydrolysis. Negative-ion electrospray ionization mass spectrometry (ESIMS) revealed that the mixture contained sulfated mono- and oligosaccharides with polymerization degree (DP) up to 6, having from 1 to 4 sulfate groups per molecule. The prevalence of oligosaccharides with even DP was observed. It could be explained by the tendency of the 3-linked α-L-fucopyranose residues to hydrolyze faster than 4-linked ones. The intermolecular sulfate transfer during autohydrolysis was detected by ESIMS, when equimolar quantities of D-Rib and D-Glc were added as acceptors. The products were singly-sulfated and hexose was about four times more effective as an acceptor, than pentose. It was impossible to record MS/MS spectra of the sulfate transfer products, since intensities of their ions were too low.

  10. Dynamics of cell wall assembly during early embryogenesis in the brown alga Fucus

    PubMed Central

    Torode, Thomas A.; Siméon, Amandine; Marcus, Susan E.; Jam, Murielle; Le Moigne, Marie-Anne; Duffieux, Delphine; Knox, J. Paul; Hervé, Cécile

    2016-01-01

    Zygotes from Fucus species have been used extensively to study cell polarization and rhizoid outgrowth, and in this model system cell wall deposition aligns with the establishment of polarity. Monoclonal antibodies are essential tools for the in situ analysis of cell wall glycans, and here we report the characteristics of six monoclonal antibodies to alginates (BAM6–BAM11). The use of these, in conjunction with monoclonal antibodies to brown algal sulfated fucans, has enabled the study of the developmental dynamics of the Fucus zygote cell walls. Young zygotes are spherical and all alginate epitopes are deposited uniformly following cellulose deposition. At germination, sulfated fucans are secreted in the growing rhizoid wall. The redistribution of cell wall epitopes was investigated during treatments that cause reorientation of the growth axis (change in light direction) or disrupt rhizoid development (arabinogalactan-protein-reactive Yariv reagent). Alginate modeling was drastically impaired in the latter, and both treatments cause a redistribution of highly sulfated fucan epitopes. The dynamics of cell wall glycans in this system have been visualized in situ for the first time, leading to an enhanced understanding of the early developmental mechanisms of Fucus species. These sets of monoclonal antibodies significantly extend the available molecular tools for brown algal cell wall studies. PMID:27811078

  11. Dynamics of cell wall assembly during early embryogenesis in the brown alga Fucus.

    PubMed

    Torode, Thomas A; Siméon, Amandine; Marcus, Susan E; Jam, Murielle; Le Moigne, Marie-Anne; Duffieux, Delphine; Knox, J Paul; Hervé, Cécile

    2016-11-01

    Zygotes from Fucus species have been used extensively to study cell polarization and rhizoid outgrowth, and in this model system cell wall deposition aligns with the establishment of polarity. Monoclonal antibodies are essential tools for the in situ analysis of cell wall glycans, and here we report the characteristics of six monoclonal antibodies to alginates (BAM6-BAM11). The use of these, in conjunction with monoclonal antibodies to brown algal sulfated fucans, has enabled the study of the developmental dynamics of the Fucus zygote cell walls. Young zygotes are spherical and all alginate epitopes are deposited uniformly following cellulose deposition. At germination, sulfated fucans are secreted in the growing rhizoid wall. The redistribution of cell wall epitopes was investigated during treatments that cause reorientation of the growth axis (change in light direction) or disrupt rhizoid development (arabinogalactan-protein-reactive Yariv reagent). Alginate modeling was drastically impaired in the latter, and both treatments cause a redistribution of highly sulfated fucan epitopes. The dynamics of cell wall glycans in this system have been visualized in situ for the first time, leading to an enhanced understanding of the early developmental mechanisms of Fucus species. These sets of monoclonal antibodies significantly extend the available molecular tools for brown algal cell wall studies.

  12. A randomised crossover placebo-controlled trial investigating the effect of brown seaweed (Ascophyllum nodosum and Fucus vesiculosus) on postchallenge plasma glucose and insulin levels in men and women.

    PubMed

    Paradis, Marie-Eve; Couture, Patrick; Lamarche, Benoît

    2011-12-01

    This study examined the impact of brown seaweed on post-load plasma glucose and insulin concentrations in men and women. Twenty-three participants (11 men, 12 women) aged 19-59 years were recruited in this double-blind, randomized, placebo-controlled crossover study. The test product consisted of a commercially available blend of brown seaweed (Ascophyllum nodosum and Fucus vesiculosus) with known inhibitory action on α-amylase and α-glucosidase activities (InSea²). Two 250 mg seaweed capsules and 2 placebo capsules were consumed on each occasion 30 min prior to the consumption of 50 g of carbohydrates from bread. Plasma glucose and insulin concentrations were measured over a period of 3 h postcarbohydrate ingestion at predetermined time points. Both treatments were separated by a 1-week washout period. Data were analysed using mixed models for repeated measures. Compared with placebo, consumption of seaweed was associated with a 12.1% reduction in the insulin incremental area under the curve (p = 0.04, adjusted for baseline) and a 7.9% increase in the Cederholm index of insulin sensitivity (p < 0.05). The single ingestion of 500 mg of brown seaweed had no significant effect on the glucose response (p = 0.24, adjusted for baseline). Glucose and insulin responses were similar between men and women. Consumption of the seaweed capsules was not associated with any adverse event. These data suggest that brown seaweed may alter the insulin homeostasis in response to carbohydrate ingestion.

  13. [Accumulation of polycyclic arenes in Baltic Sea algae].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Kukk, Kh A

    1985-01-01

    The paper presents data on the level of benzo(a)pyrene (BP) and some other polycyclic arenes in alga and phanerogam specimens from different gulfs of the Baltic Sea. Algae were shown to absorb BP from sea water. The mean concentration of BP in sea water was under 0.004 microgram/1, while in algae it ranged 0.1-21.2 micrograms/kg dry weight. Algae accumulate BP to a higher degree than phanerogams. The highest concentrations of BP were found in algae Enteromorpha while the lowest ones in Furcellaria. In annual green algae, BP level was higher in autumn, i. e. at the end of vegetation period, than in spring. Brown algae Fucus vesiculosus is recommended for monitoring polycyclic arene pollution in the area from Vormsi Island to Käsmu and green algae Cladophora or Enteromorpha in the eastern part of the Finnish Gulf.

  14. [Antithrombotic and hemorrhagic activities of fucoidan isolated from Fucus evanescens brown algae].

    PubMed

    Drozd, N N; Miftakhova, N T; Savchik, E Iu; Kalinina, T B; Makarov, V A; Imbs, T I; Zviagintseva, T N; Kuznetsova, T A; Besednova, N N

    2011-01-01

    The antithrombotic and hemorrhagic activities of fucoidan with molecular weight within 20 - 40 kD isolation from Fucus evanescens seaweed have been investigated. The antithrombin activity of fucoidan is 41 +/- 9 aIIa IU/mg and the anti-factor Oà activity is 38 +/- 8 aOà IU/mg. The antithrombin and anti-factor Oà activities of plasma, antithrombotic activity (100% prevention of formation of a blood clot observed at a dose of 10 mg/kg), and hemorrhagic activity (to a lesser degree, than that of unfractionated heparin in comparable antithrombotic activity doses) increase as the doses of fucoidan increases from 2.5 to 10 mg/kg at intravenous injection in rats.

  15. Uptake and distribution of technetium in several marine algae

    SciTech Connect

    Bonotto, S.; Gerber, G.B.; Garten, C.T. Jr.; Vandecasteele, C.M.; Myttenaere, C.; Van Baelen, J.; Cogneau, M.; van der Ben, D.

    1983-01-01

    The uptake or chemical form of technetium in different marine algae (Acetabularia, Cystoseira, Fucus) has been examined and a simple model to explain the uptake of technetium in the unicellular alga, Acetabularia, has been conceptualized. At low concentrations in the external medium, Acetabularia can rapidly concentrate technetium. Concentration factors in excess of 400 can be attained after a time of about 3 weeks. At higher mass concentrations in the medium, uptake of technetium by Acetabularia becomes saturated resulting in a decreased concentration factor (approximately 10 after 4 weeks). Approximately 69% of the total radioactivity present in /sup 95m/Tc labelled Acetabularia is found in the cell cytosol. In Fucus vesiculosus, labelled with /sup 95m/Tc, a high percentage of technetium is present in soluble ionic forms while approximately 40% is bound, in this brown alga, in proteins and polysaccharides associated with cell walls. In the algal cytosol of Fucus vesiculosus, about 45% of the /sup 95m/Tc appears to be present as anionic TcO/sup -//sub 4/ and the remainder is bound to small molecules. 8 references, 5 figures, 1 table.

  16. Effect of enzyme preparation from the marine mollusk Littorina kurila on fucoidan from the brown alga Fucus distichus.

    PubMed

    Bilan, M I; Kusaykin, M I; Grachev, A A; Tsvetkova, E A; Zvyagintseva, T N; Nifantiev, N E; Usov, A I

    2005-12-01

    A fucoidanase preparation from the marine mollusk Littorina kurila cleaved some glycosidic bonds in fucoidan from the brown alga Fucus distichus, but neither fucose nor lower oligosaccharides were produced. The main product isolated from the incubation mixture was a polysaccharide built up of disaccharide repeating units -->3)-alpha-L-Fucp-(2,4-di-SO3(-))-(1-->4)-alpha-L-Fucp-(2SO3(-))-(1-->, the structure coinciding with the idealized formula proposed for the initial substance. A polymer fraction with the same carbohydrate chain but sulfated only at positions 2 and nonstoichiometrically acetylated at positions 3 and 4 of fucose residues was isolated as a minor component. It is suggested that the native polysaccharide should contain small amounts of non-sulfated and non-acetylated fucose residues, and only their glycosidic bonds are cleaved by the enzyme. The enzymatic hydrolysis showed that irregular regions of the native polysaccharide containing acetylated and partially sulfated repeating units were assembled in blocks.

  17. Biosorption of lead and nickel by biomass of marine algae

    SciTech Connect

    Holan, Z.R.; Volesky, B. . Dept. of Chemical Engineering)

    1994-05-01

    Screening tests of different marine algae biomass types revealed a high passive biosorptive uptake of lead up to 270 mg Pb/g of biomass in some brown marine algae. Members of the order Fucales performed particularly well in this descending sequence: Fucus > Ascophyllum > Sargassum. Although decreasing the swelling of wetted biomass particles, their reinforcement by crosslinking may significantly affect the biosorption performance. Lead uptakes up to 370 mg Pb/g were observed in crosslinked Fucus vesiculosus and Ascophyllum nodosum. At low equilibrium residual concentrations of lead in solution, however, ion exchange resin Amberlite IR-120 had a higher lead uptake than the biosorbent materials. An order-of-magnitude lower uptake of nickel was observed in all of the sorbent materials examined.

  18. Convergent adaptation to a marginal habitat by homoploid hybrids and polyploid ecads in the seaweed genus Fucus.

    PubMed

    Coyer, James A; Hoarau, Galice; Pearson, Gareth A; Serrão, Ester A; Stam, Wytze T; Olsen, Jeanine L

    2006-09-22

    Hybridization and polyploidy are two major sources of genetic variability that can lead to adaptation in new habitats. Most species of the brown algal genus Fucus are found along wave-swept rocky shores of the Northern Hemisphere, but some species have adapted to brackish and salt marsh habitats. Using five microsatellite loci and mtDNA RFLP, we characterize two populations of morphologically similar, muscoides-like Fucus inhabiting salt marshes in Iceland and Ireland. The Icelandic genotypes were consistent with Fucus vesiculosus x Fucus spiralis F1 hybrids with asymmetrical hybridization, whereas the Irish ones consisted primarily of polyploid F. vesiculosus.

  19. Determination of Plutonium Activity Concentrations and 240Pu/239Pu Atom Ratios in Brown Algae (Fucus distichus) Collected from Amchitka Island, Alaska.

    SciTech Connect

    Hamilton, T F; Brown, T A; Marchetti, A A; Martinelli, R E; Kehl, S R

    2005-05-02

    Plutonium-239 ({sup 239}Pu) and plutonium-240 ({sup 240}Pu) activity concentrations and {sup 240}Pu/{sup 239}Pu atom ratios are reported for Brown Algae (Fucus distichus) collected from the littoral zone of Amchitka Island (Alaska) and at a control site on the Alaskan peninsula. Plutonium isotope measurements were performed in replicate using Accelerator Mass Spectrometry (AMS). The average {sup 240}Pu/{sup 239}Pu atom ratio observed in dried Fucus d. collected from Amchitka Island was 0.227 {+-} 0.007 (n=5) and compares with the expected {sup 240}Pu/{sup 239}Pu atom ratio in integrated worldwide fallout deposition in the Northern Hemisphere of 0.1805 {+-} 0.0057 (Cooper et al., 2000). In general, the characteristically high {sup 240}Pu/{sup 239}Pu content of Fucus d. analyzed in this study appear to indicate the presence of a discernible basin-wide secondary source of plutonium entering the marine environment. Of interest to the study of plutonium source terms within the Pacific basin are reports of elevated {sup 240}Pu/{sup 239}Pu atom ratios in fallout debris from high-yield atmospheric nuclear tests conducted in the Marshall Islands during the 1950s (Diamond et al., 1960), the wide range of {sup 240}Pu/{sup 239}Pu atom ratio values (0.19 to 0.34) observed in sea water, sediments, coral and other environmental media from the North Pacific Ocean (Hirose et al., 1992; Buesseler, 1997) and updated estimates of the relative contributions of close-in and intermediate fallout deposition on oceanic inventories of radionuclidies, especially in the Northern Pacific Ocean (Hamilton, 2004).

  20. Isolation of fucoxanthin and highly unsaturated monogalactosyldiacylglycerol from brown alga Fucus evanescens C Agardh and in vitro investigation of their antitumor activity.

    PubMed

    Imbs, Tatiana I; Ermakova, Svetlana P; Fedoreyev, Sergey A; Anastyuk, Stanislav D; Zvyagintseva, Tatiana N

    2013-10-01

    Fucoxanthin (FX) and highly unsaturated monogalactosyldiacylglycerol (MGDG) were isolated from the ethanol extract of brown alga Fucus evanescens. Their structures were identified by nuclear magnetic resonance, complemented by electrospray ionization mass spectrometry (ESIMS). MGDG was identified as 1-O-(5Z,8Z,11Z,14Z,17Z-eicosapentanoyl)-2-O-(6Z,9Z,12Z,15Z-octadecatetraenoyl)-3-O-β-D-galactopiranosyl-sn-glycerol. Antitumor activity of these compounds was tested on human melanoma (SK-MEL-28) cells. MGDG and FX inhibited the growth of human melanoma cells in a dose-dependent manner. IC50 values for growth inhibition were 104 and 114 μM, correspondently.

  1. Evaluation of the contamination of marine algae (seaweed) from the St. Lawrence River and likely to be consumed by humans

    SciTech Connect

    Phaneuf, D.; Cote, I.; Dumas, P.; Ferron, L.A.; LeBlanc, A.

    1999-02-01

    The goal of the study was to assess the contamination of marine algae (seaweeds) growing in the St. Lawrence River estuary and Gulf of St. Lawrence and to evaluate the risks to human health from the consumption of these algae. Algae were collected by hand at low tide. A total of 10 sites on the north and south shores of the St. Lawrence as well as in Baie des Chaleurs were sampled. The most frequently collected species of algae were Fucus vesiculosus, Ascophyllum nodosum, Laminaria Longicruris, Palmaria palmata, Ulva lactuca, and Fucus distichus. Alga samples were analyzed for metals iodine, and organochlorines. A risk assessment was performed using risk factors. In general, concentrations in St. Lawrence algae were not very high. Consequently, health risks associated with these compounds in St. Lawrence algae were very low. Iodine concentration, on the other hand, could be of concern with regard to human health. Regular consumption of algae, especially of Laminaria sp., could result in levels of iodine sufficient to cause thyroid problems. For regular consumers, it would be preferable to choose species with low iodine concentrations, such as U. lactuca and P. palmata, in order to prevent potential problems. Furthermore, it would also be important to assess whether preparation for consumption or cooking affects the iodine content of algae. Algae consumption may also have beneficial health effects. Scientific literature has shown that it is a good source of fiber and vitamins, especially vitamin B{sub 12}.

  2. Radiocarbon behaviour in seawater and the brown algae Fucus serratus in the vicinity of the COGEMA La Hague spent fuel reprocessing plant (Goury)--France.

    PubMed

    Douville, Eric; Fiévet, Bruno; Germain, Pierre; Fournier, Marc

    2004-01-01

    Extensive studies of the radiocarbon (14C) distribution and transfer in the marine environment of the North-Cotentin peninsula and along the English Channel have been carried out. The main aims of these studies have been to estimate the spatial and temporal variation of the 14C concentration in seawater and to calculate 14C concentration factors for some biological species. Such information will be helpful in order to calculate precisely radiation doses to humans. First results obtained in the vicinity of the COGEMA La Hague nuclear plant (Goury) indicate a 14C labelling of the dissolved inorganic carbon (DIC) in seawater (8.0-26.2 Bq.m(-3)) and a tight relationship between the 14C in the liquid releases from the plant and the 14C concentrations in DIC. The particulate organic carbon (POC) is also labelled. The concentration factor calculations for the brown algae (Fucus serratus) sampled from Goury, and also along the English Channel, give 14C values around 3000 Bq.kg(-1) fresh weight / Bq.L(-1).

  3. Pronounced gradients of light, photosynthesis and O2 consumption in the tissue of the brown alga Fucus serratus.

    PubMed

    Lichtenberg, Mads; Kühl, Michael

    2015-08-01

    Macroalgae live in an ever-changing light environment affected by wave motion, self-shading and light-scattering effects, and on the thallus scale, gradients of light and chemical parameters influence algal photosynthesis. However, the thallus microenvironment and internal gradients remain underexplored. In this study, microsensors were used to quantify gradients of light, O2 concentration, variable chlorophyll fluorescence, photosynthesis and O2 consumption as a function of irradiance in the cortex and medulla layers of Fucus serratus. The two cortex layers showed more efficient light utilization compared to the medulla, calculated both from electron transport rates through photosystem II and from photosynthesis-irradiance curves. At moderate irradiance, the upper cortex exhibited onset of photosynthetic saturation, whereas lower thallus layers exhibited net O2 consumption. O2 consumption rates in light varied with depth and irradiance and were more than two-fold higher than dark respiration. We show that the thallus microenvironment of F. serratus exhibits a highly stratified balance of production and consumption of O2 , and when the frond was held in a fixed position, high incident irradiance levels on the upper cortex did not saturate photosynthesis in the lower thallus layers. We discuss possible photoadaptive responses and consequences for optimizing photosynthetic activity on the basis of vertical differences in light attenuation coefficients.

  4. Thermal stress resistance of the brown alga Fucus serratus along the North-Atlantic coast: acclimatization potential to climate change.

    PubMed

    Jueterbock, Alexander; Kollias, Spyros; Smolina, Irina; Fernandes, Jorge M O; Coyer, James A; Olsen, Jeanine L; Hoarau, Galice

    2014-02-01

    Seaweed-dominated communities are predicted to disappear south of 45° latitude on North-Atlantic rocky shores by 2200 because of climate change. The extent of predicted habitat loss, however, could be mitigated if the seaweeds' physiology is sufficiently plastic to rapidly acclimatize to the warmer temperatures. The main objectives of this study were to identify whether the thermal tolerance of the canopy-forming seaweed Fucus serratus is population-specific and where temperatures are likely to exceed its tolerance limits in the next 200 years. We measured the stress response of seaweed samples from four populations (Norway, Denmark, Brittany and Spain) to common-garden heat stress (20 °C-36 °C) in both photosynthetic performance and transcriptomic upregulation of heat shock protein genes. The two stress indicators did not correlate and likely measured different cellular components of the stress response, but both indicators revealed population-specific differences, suggesting ecotypic differentiation. Our results confirmed that thermal extremes will regularly reach physiologically stressful levels in Brittany (France) and further south by the end of the 22nd century. Although heat stress resilience in photosynthetic performance was higher at the species' southern distributional edge in Spain, the hsp expression pattern suggested that this edge-population experienced reduced fitness and limited responsiveness to further stressors. Thus, F. serratus may be unable to mitigate its predicted northward shift and may be at high risk to lose its center of genetic diversity and adaptability in Brittany (France). As it is an important intertidal key species, the disappearance of this seaweed will likely trigger major ecological changes in the entire associated ecosystem.

  5. Glutathione-S-transferase activity of Fucus spp. as a biomarker of environmental contamination.

    PubMed

    Cairrão, E; Couderchet, M; Soares, A M V M; Guilhermino, L

    2004-12-20

    Coastal zones are important areas from both ecological and economical points of view. However, in the last decades, in several regions of the globe, they have been increasingly impacted by complex discharges of contaminants and by marine traffic accidents. The Portuguese Atlantic coast is particularly exposed to these contaminants due to the proximity of important navigation routes. Several rocky shore organisms have been tested and used as bioindicators of environmental contamination. However, to the best of our knowledge Fucus spp., which are key species in rocky shore communities, have not been used as bioindicators in monitoring studies based on biomarkers. The objective of this study was to investigate the potential of glutathione-S-transferase (GST) activity of several Fucus species (Fucus ceranoides, Fucus spiralis var. platycarpus, Fucus spiralis var. spiralis and Fucus vesiculosus var. vesiculosus) to discriminate sites with different contamination levels along the Portuguese Northwestern coast, between the Minho river estuary and the Aveiro's Lagoon, as an environmental biomarker. With the exception of F. spiralis var. spiralis, for which a confusing pattern of activity was found requiring further analysis, all the other species and varieties showed higher GST levels in more contaminated sites than in less contaminated ones, indicating that Fucus spp. are suitable for use as bioindicators and their GSTs as biomarkers of environmental contamination in coastal zones and estuaries.

  6. Study of heavy metals and other elements in macrophyte algae using energy-dispersive X-ray fluorescence

    SciTech Connect

    Carvalho, M.L.; Amorim, P.; Marques, M.I.M.; Ramos, M.T.; Ferreira, J.G.

    1997-04-01

    Fucus vesiculosus L. seaweeds from three estuarine stations were analyzed by X-ray fluorescence, providing results for the concentration of total K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Sr, and Pb. Four different structures of the algae (base, stipe, reproductive organs, and growing tips) were analyzed to study the differential accumulation of heavy metals by different parts of Fucus. Some elements (e.g., Cu and Fe) are preferentially accumulated in the base of the algae, whereas others (e.g., As) exhibit higher concentrations in the reproductive organs and growing tips. The pattern of accumulation in different structures is similar for Cu, Zn, and Pb, but for other metals there is considerable variability in accumulation between parts of the plant. This is important in determining which structures of the plant should be used for biomonitoring. For samples collected at stations subject to differing metal loads, the relative elemental composition is approximately constant, notwithstanding significant variation in absolute values. The proportion of metals in Fucus is similar to that found in other estuaries, where metal concentrations are significantly lower. Energy-dispersive X-ray fluorescence has been shown to be a suitable technique for multielement analysis in this type of sample. No chemical pretreatment is required, minimizing sample contamination. The small amount of sample required, and the wide range of elements that can be detected simultaneously make energy-dispersive X-ray fluorescence a valuable tool for pollution studies.

  7. PDZ-binding kinase/T-LAK cell-originated protein kinase is a target of the fucoidan from brown alga Fucus evanescens in the prevention of EGF-induced neoplastic cell transformation and colon cancer growth.

    PubMed

    Vishchuk, Olesia S; Sun, Huimin; Wang, Zhe; Ermakova, Svetlana P; Xiao, JuanJuan; Lu, Tao; Xue, PeiPei; Zvyagintseva, Tatyana N; Xiong, Hua; Shao, Chen; Yan, Wei; Duan, Qiuhong; Zhu, Feng

    2016-04-05

    The fucoidan with high anticancer activity was isolated from brown alga Fucus evanescens. The compound effectively prevented EGF-induced neoplastic cell transformation through inhibition of TOPK/ERK1/2/MSK 1 signaling axis. In vitro studies showed that the fucoidan attenuated mitogen-activated protein kinases downstream signaling in a colon cancer cells with different expression level of TOPK, resulting in growth inhibition. The fucoidan exerts its effects by directly interacting with TOPK kinase in vitro and ex vivo and inhibits its kinase activity. In xenograft animal model, oral administration of the fucoidan suppressed HCT 116 colon tumor growth. The phosphorylation of TOPK downstream signaling molecules in tumor tissues was also inhibited by the fucoidan. Taken together, our findings support the cancer preventive efficacy of the fucoidan through its targeting of TOPK for the prevention of neoplastic cell transformation and progression of colon carcinomas in vitro and ex vivo.

  8. PDZ-binding kinase/T-LAK cell-originated protein kinase is a target of the fucoidan from brown alga Fucus evanescens in the prevention of EGF-induced neoplastic cell transformation and colon cancer growth

    PubMed Central

    Wang, Zhe; Ermakova, Svetlana P.; Xiao, JuanJuan; Lu, Tao; Xue, PeiPei; Zvyagintseva, Tatyana N.; Xiong, Hua; Shao, Chen; Yan, Wei; Duan, Qiuhong; Zhu, Feng

    2016-01-01

    The fucoidan with high anticancer activity was isolated from brown alga Fucus evanescens. The compound effectively prevented EGF-induced neoplastic cell transformation through inhibition of TOPK/ERK1/2/MSK 1 signaling axis. In vitro studies showed that the fucoidan attenuated mitogen-activated protein kinases downstream signaling in a colon cancer cells with different expression level of TOPK, resulting in growth inhibition. The fucoidan exerts its effects by directly interacting with TOPK kinase in vitro and ex vivo and inhibits its kinase activity. In xenograft animal model, oral administration of the fucoidan suppressed HCT 116 colon tumor growth. The phosphorylation of TOPK downstream signaling molecules in tumor tissues was also inhibited by the fucoidan. Taken together, our findings support the cancer preventive efficacy of the fucoidan through its targeting of TOPK for the prevention of neoplastic cell transformation and progression of colon carcinomas in vitro and ex vivo. PMID:26936995

  9. Cell Wall Assembly in Fucus Zygotes

    PubMed Central

    Quatrano, Ralph S.; Stevens, Patricia T.

    1976-01-01

    Fertilization triggers the assembly of a cell wall around the egg cell of three brown algae, Fucus vesiculosus, F. distichus, and F. inflatus. New polysaccharide polymers are continually being added to the cell wall during the first 24 hours of synchronous embryo development. This wall assembly involves the extracellular deposition of fibrillar material by cytoplasmic vesicles fusing with the plasma membrane. One hour after fertilization a fragmented wall can be isolated free of cytoplasm and contains equal amounts of cellulose and alginic acid with no fucose-containing polymers (fucans) present. Birefringence of the wall caused by oriented cellulose microfibrils is not detected in all zygotes until 4 hours, at which time intact cell walls can be isolated that retain the shape of the zygote. These walls have a relatively low ratio of fucose to xylose and little sulfate when compared to walls from older embryos. When extracts of walls from 4-hour zygotes are subjected to cellulose acetate electrophoresis at pH 7, a single fucan (F1) can be detected. By 12 hours, purified cell walls are composed of fucans containing a relatively high ratio of fucose to xylose and high levels of sulfate, and contain a second fucan (F2) which is electrophoretically distinct from F1. F2 appears to be deposited in only a localized region of the wall, that which elongates to form the rhizoid cell. Throughout wall assembly, the polyuronide block co-polymer alginic acid did not significantly vary its mannuronic (M) to guluronic (G) acid ratio (0.33-0.55) or its block distribution (MG, 54%; GG, 30%; MM, 16%). From 6 to 24 hours of embryo development, the proportion of the major polysaccharide components found in purified walls is stable. Alginic acid is the major polymer and comprises about 60% of the total wall, while cellulose and the fucans each make-up about 20% of the remainder. During the extracellular assembly of this wall, the intracellular levels of the storage glucan laminaran

  10. Surfing the wave on a borrowed board: range expansion and spread of introgressed organellar genomes in the seaweed Fucus ceranoides L.

    PubMed

    Neiva, João; Pearson, Gareth A; Valero, Myriam; Serrão, Ester A

    2010-11-01

    For many taxa, introgression represents an important source of genetic variation, but the specific contexts allowing locally introgressed material to spread and largely replace native allelic lineages throughout a species range remain poorly understood. Recent demographic-genetic simulations of spatial expansions show that the stochastic surfing of alien alleles during range expansions may constitute a general mechanism leading to extensive introgression, but empirical evidence remain scarce and difficult to distinguish from selection. In this study, we report a compelling case of such a phenomenon in the estuarine alga Fucus ceranoides. We re-assessed the phylogenetic relationships among F. ceranoides and its marine congeners F. vesiculosus and F. spiralis using nuclear, mitochondrial and chloroplast sequence data, and conducted a mtDNA phylogeographic survey in F. ceranoides. Our phylogenetic analyses revealed a recent and asymmetric introgression of a single F. vesiculosus cytoplasm into F. ceranoides. The phylogeographic scope of introgression was striking, with native and introgressed mtDNA displaying disjunct distributions south and north of the English Channel. A putative Pleistocene climatic refugium was detected in NW Iberia, and the extensive and exclusive spread of the alien cytoplasm throughout Northern Europe was inferred to have occurred concurrently with the species post-glacial, northwards range expansion. This massive spread of a foreign organelle throughout the entire post-glacial recolonization range represents good empirical evidence of an alien cytoplasm surfing the wave of a range expansion and the first description of such a phenomenon in the marine realm.

  11. Calmodulin-binding proteins are developmentally regulated in gametes and embryos of fucoid algae

    SciTech Connect

    Brawley, S.H.; Roberts, D.M.

    1989-02-01

    Calcium-binding proteins and calmodulin-binding proteins were identified in gametes and zygotes of the marine brown algae Fucus vesiculosus, Fucus distichus, and Pelvetia fastigiata using gel (SDS-PAGE) overlay techniques. A calcium current appears to be important during cell polarization in fucoid zygotes, but there are no biochemical data on calcium-binding proteins in these algae. By using a sensitive 45Ca2+ overlay method designed to detect high-affinity calcium-binding proteins, at least 9-11 polypeptides were detected in extracts of fucoid gametes and zygotes. All samples had calcium-binding proteins with apparent molecular weights of about 17 and 30 kDa. A 17-kDa calcium-binding protein was purified by calcium-dependent hydrophobic chromatography and was identified as calmodulin by immunological and enzyme activator criteria. A 125I-calmodulin overlay assay was used to identify potential targets of calmodulin action. Sperm contained one major calmodulin-binding protein of about 45 kDa. Eggs lacked major calmodulin-binding activity. A 72-kDa calmodulin-binding protein was prominent in zygotes from 1-65 hr postfertilization. Both calmodulin-binding proteins showed calcium-dependent binding activity. Overall, the data suggest that the appearance and distribution of certain calcium-binding and calmodulin-binding proteins are under developmental regulation, and may reflect the different roles of calcium during fertilization and early embryogenesis.

  12. Complete Plastid Genome Sequence of the Brown Alga Undaria pinnatifida.

    PubMed

    Zhang, Lei; Wang, Xumin; Liu, Tao; Wang, Guoliang; Chi, Shan; Liu, Cui; Wang, Haiyang

    2015-01-01

    In this study, we fully sequenced the circular plastid genome of a brown alga, Undaria pinnatifida. The genome is 130,383 base pairs (bp) in size; it contains a large single-copy (LSC, 76,598 bp) and a small single-copy region (SSC, 42,977 bp), separated by two inverted repeats (IRa and IRb: 5,404 bp). The genome contains 139 protein-coding, 28 tRNA, and 6 rRNA genes; none of these genes contains introns. Organization and gene contents of the U. pinnatifida plastid genome were similar to those of Saccharina japonica. There is a co-linear relationship between the plastid genome of U. pinnatifida and that of three previously sequenced large brown algal species. Phylogenetic analyses of 43 taxa based on 23 plastid protein-coding genes grouped all plastids into a red or green lineage. In the large brown algae branch, U. pinnatifida and S. japonica formed a sister clade with much closer relationship to Ectocarpus siliculosus than to Fucus vesiculosus. For the first time, the start codon ATT was identified in the plastid genome of large brown algae, in the atpA gene of U. pinnatifida. In addition, we found a gene-length change induced by a 3-bp repetitive DNA in ycf35 and ilvB genes of the U. pinnatifida plastid genome.

  13. Complete Plastid Genome Sequence of the Brown Alga Undaria pinnatifida

    PubMed Central

    Liu, Tao; Wang, Guoliang; Chi, Shan; Liu, Cui; Wang, Haiyang

    2015-01-01

    In this study, we fully sequenced the circular plastid genome of a brown alga, Undaria pinnatifida. The genome is 130,383 base pairs (bp) in size; it contains a large single-copy (LSC, 76,598 bp) and a small single-copy region (SSC, 42,977 bp), separated by two inverted repeats (IRa and IRb: 5,404 bp). The genome contains 139 protein-coding, 28 tRNA, and 6 rRNA genes; none of these genes contains introns. Organization and gene contents of the U. pinnatifida plastid genome were similar to those of Saccharina japonica. There is a co-linear relationship between the plastid genome of U. pinnatifida and that of three previously sequenced large brown algal species. Phylogenetic analyses of 43 taxa based on 23 plastid protein-coding genes grouped all plastids into a red or green lineage. In the large brown algae branch, U. pinnatifida and S. japonica formed a sister clade with much closer relationship to Ectocarpus siliculosus than to Fucus vesiculosus. For the first time, the start codon ATT was identified in the plastid genome of large brown algae, in the atpA gene of U. pinnatifida. In addition, we found a gene-length change induced by a 3-bp repetitive DNA in ycf35 and ilvB genes of the U. pinnatifida plastid genome. PMID:26426800

  14. Arabinogalactan proteins have deep roots in eukaryotes: identification of genes and epitopes in brown algae and their role in Fucus serratus embryo development.

    PubMed

    Hervé, Cécile; Siméon, Amandine; Jam, Murielle; Cassin, Andrew; Johnson, Kim L; Salmeán, Armando A; Willats, William G T; Doblin, Monika S; Bacic, Antony; Kloareg, Bernard

    2016-03-01

    Arabinogalactan proteins (AGPs) are highly glycosylated, hydroxyproline-rich proteins found at the cell surface of plants, where they play key roles in developmental processes. Brown algae are marine, multicellular, photosynthetic eukaryotes. They belong to the phylum Stramenopiles, which is unrelated to land plants and green algae (Chloroplastida). Brown algae share common evolutionary features with other multicellular organisms, including a carbohydrate-rich cell wall. They differ markedly from plants in their cell wall composition, and AGPs have not been reported in brown algae. Here we investigated the presence of chimeric AGP-like core proteins in this lineage. We report that the genome sequence of the brown algal model Ectocarpus siliculosus encodes AGP protein backbone motifs, in a gene context that differs considerably from what is known in land plants. We showed the occurrence of AGP glycan epitopes in a range of brown algal cell wall extracts. We demonstrated that these chimeric AGP-like core proteins are developmentally regulated in embryos of the order Fucales and showed that AGP loss of function seriously impairs the course of early embryogenesis. Our findings shine a new light on the role of AGPs in cell wall sensing and raise questions about the origin and evolution of AGPs in eukaryotes.

  15. Algae.

    PubMed

    Raven, John A; Giordano, Mario

    2014-07-07

    Algae frequently get a bad press. Pond slime is a problem in garden pools, algal blooms can produce toxins that incapacitate or kill animals and humans and even the term seaweed is pejorative - a weed being a plant growing in what humans consider to be the wrong place. Positive aspects of algae are generally less newsworthy - they are the basis of marine food webs, supporting fisheries and charismatic marine megafauna from albatrosses to whales, as well as consuming carbon dioxide and producing oxygen. Here we consider what algae are, their diversity in terms of evolutionary origin, size, shape and life cycles, and their role in the natural environment and in human affairs.

  16. The influence of coastal topography, circulation patterns, and rafting in structuring populations of an intertidal alga.

    PubMed

    Muhlin, J F; Engel, C R; Stessel, R; Weatherbee, R A; Brawley, S H

    2008-03-01

    Understanding the dispersal processes that influence genetic structure in marine species requires estimating gene flow in a dynamic, fluid environment that is often poorly characterized at scales relevant to multiple dispersive stages (e.g. spores, gametes, zygotes, larvae, adults). We examine genetic structure in the marine alga Fucus vesiculosus L., which inhabits moderately exposed shores in the northern Atlantic but releases gametes only under sunny, calm conditions. We predicted genetic structure would correlate with coastal topography because weather frequently varies across coastal promontories on the Maine shore when F. vesiculosus is reproductive, which causes one side to experience high levels of water motion (= no gamete release) while one side is calm (= gamete release). Furthermore, we expected that the effect of low dispersal capacities of gametes and zygotes would result in spatial genetic structure over short distances. Using surface drifters, we characterized near-shore circulation patterns around the study sites to investigate whether directionality of gene flow was correlated with directionality of currents. We found significant genetic differentiation among sites sampled at two different peninsulas, but patterns of differentiation were unrelated to coastal topography and there was no within-site spatial structuring. Our genetic and near-shore circulation data, combined with an examination of gamete longevity, support the dependency of gene flow on storm-detached, rafting, reproductive adults. This study highlights the significance of rafting as a mechanism for structuring established populations of macroalgae and associated biota and demonstrates the importance of coupling population genetics' research with relevant hydrodynamic studies.

  17. Monoclonal Antibodies Directed to Fucoidan Preparations from Brown Algae

    PubMed Central

    Torode, Thomas A.; Marcus, Susan E.; Jam, Murielle; Tonon, Thierry; Blackburn, Richard S.; Hervé, Cécile; Knox, J. Paul

    2015-01-01

    Cell walls of the brown algae contain a diverse range of polysaccharides with useful bioactivities. The precise structures of the sulfated fucan/fucoidan group of polysaccharides and their roles in generating cell wall architectures and cell properties are not known in detail. Four rat monoclonal antibodies, BAM1 to BAM4, directed to sulfated fucan preparations, have been generated and used to dissect the heterogeneity of brown algal cell wall polysaccharides. BAM1 and BAM4, respectively, bind to a non-sulfated epitope and a sulfated epitope present in the sulfated fucan preparations. BAM2 and BAM3 identified additional distinct epitopes present in the fucoidan preparations. All four epitopes, not yet fully characterised, occur widely within the major brown algal taxonomic groups and show divergent distribution patterns in tissues. The analysis of cell wall extractions and fluorescence imaging reveal differences in the occurrence of the BAM1 to BAM4 epitopes in various tissues of Fucus vesiculosus. In Ectocarpus subulatus, a species closely related to the brown algal model Ectocarpus siliculosus, the BAM4 sulfated epitope was modulated in relation to salinity levels. This new set of monoclonal antibodies will be useful for the dissection of the highly complex and yet poorly resolved sulfated polysaccharides in the brown algae in relation to their ecological and economic significance. PMID:25692870

  18. Fucus spp. as a mercury contamination bioindicator in costal areas (Northwestern Portugal).

    PubMed

    Cairrão, E; Pereira, M J; Pastorinho, M R; Morgado, F; Soares, A M V M; Guilhermino, L

    2007-10-01

    Mercury has been considered as one of the most important pollutants in coastal and estuarine areas. Efforts have been made to detect, as early as possible, the effects of this and other metals in several species. Macroalgae, particularly Fucus spp., have been widely used as biomonitors of metal pollution. In this study, three Fucus species (F. spiralis, F. vesiculosus and F. ceranoides) were collected from several sampling sites in Portugal. The concentrations of mercury were determined in three structural parts (holdfast, stipe and receptacles). Two different techniques were used to determine mercury concentrations. Almost all mercury concentrations (in sediments and in water) were below national and international standards. Mercury concentration in the specimens (0.012-0.061 microg g(-1) for receptacles, 0.028-0.221 microg g(-1) for stipe and 0.029-0.287 microg g(-1) for holdfast) was always higher that those obtained for the sediment (0.001-0.112 microg g(-1)). With few exceptions the contrary was found for receptacles. In general, a good agreement between concentrations of mercury in sediment and Fucus was found. The results indicate that Fucus accumulate mercury and may be a suitable species for use in risk assessment for coast and estuarine areas, by providing valuable information regarding the levels of mercury that will be available for the consumers of Fucus spp.

  19. Impacts of ambient salinity and copper on brown algae: 1. Interactive effects on photosynthesis, growth, and copper accumulation.

    PubMed

    Connan, Solène; Stengel, Dagmar B

    2011-07-01

    The effect of copper enrichment and salinity on growth, photosynthesis and copper accumulation of two temperate brown seaweeds, Ascophyllum nodosum and Fucus vesiculosus, was investigated in laboratory experiments. A significant negative impact of reduced salinity on photosynthetic activity and growth was observed for both species. After 15 days at a salinity of 5, photosynthesis of A. nodosum was entirely inhibited and growth ceased at a salinity of 15. Increased copper concentration negatively affected photosynthetic activity of A. nodosum and F. vesiculosus resulting in chlorosis and reduced seaweed growth; 5 mg L⁻¹ copper caused an inhibition of the photosynthesis and the degradation of seaweed tips. Under reduced salinity, copper toxicity was enhanced and caused an earlier impact on the physiology of seaweed tips. After exposure to copper and different salinities for 15 days, copper contents of seaweeds were closely related to copper concentration in the water; seaweed copper contents reached their maximum after 1 day of exposure; contents only increased again when additional, free copper was added to the water. At high water copper concentrations or low salinity, or a combination of both, copper content of A. nodosum decreased. By contrast, copper content of F. vesiculosus increased, suggesting that different binding sites or uptake mechanisms exist in the two species. The results suggest that when using brown seaweeds in biomonitoring in situ, any change in the environment will directly and significantly affect algal physiology and thus their metal binding capacity; the assessment of the physiological status of the algae in combination with the analysis of thallus metal content will enhance the reliability of the biomonitoring process.

  20. Biosorption of cadmium by biomass of marine algae

    SciTech Connect

    Holan, Z.R.; Volesky, B.; Prasetyo, I. )

    1993-04-01

    Biomass of nonliving, dried brown marine algae Sargassum natans, Fucus vesiculosus, and Ascophyllum nodosum demonstrated high equilibrium uptake of cadmium from aqueous solutions. The metal uptake by these materials was quantitatively evaluated using sorption isotherms. Biomass of A. nodosum accumulated the highest amount of cadmium exceeding 100 mg Cd[sup 2+]/g (at the residual concentration of 100 mg Cd/L and pH 3.5), outperforming a commercial ion exchange resin DUOLITE GT-73. A new biosorbent material based on A. nodosum biomass was obtained by reinforcing the algal biomass by formaldehyde cross-linking. The prepared sorbent possessed good mechanical properties, chemical stability of the cell wall polysaccharides and low swelling volume. Desorption of deposited cadmium with 0.1-0.5 M HCl resulted in no changes of the biosorbent metal uptake capacity through five subsequent adsorption/desorption cycles. There was no damage to the biosorbent which retained its macroscopic appearance and performance in repeated metal uptake/elution cycles.

  1. Effects of temperature on the production of hydrogen peroxide and volatile halocarbons by brackish-water algae.

    PubMed

    Abrahamsson, Katarina; Choo, Kyung Sil; Pedersén, Marianne; Johansson, Gustav; Snoeijs, Pauli

    2003-10-01

    Marine algae produce volatile halocarbons, which have an ozone-depleting potential. The formation of these compounds is thought to be related to oxidative stress, involving H2O2 and algal peroxidases. In our study we found strong correlations between the releases of H2O2 and brominated and some iodinated compounds to the seawater medium, but no such correlation was found for CHCl3, suggesting the involvement of other formation mechanisms as well. Little is known about the effects of environmental factors on the production of volatile halocarbons by algae and in the present study we focused on the influence of temperature. Algae were sampled in an area of the brackish Baltic Sea that receives thermal discharge, allowing us to collect specimens of the same species that were adapted to different field temperature regimes. We exposed six algal species (the diatom Pleurosira laevis, the brown alga Fucus vesiculosus and four filamentous green algae, Cladophora glomerata, Enteromorpha ahlneriana, E. flexuosa and E. intestinalis) to temperature changes of 0-11 degrees C under high irradiation to invoke oxidative stress. The production rates, as well as the quantitative composition of 16 volatile halocarbons, were strongly species-dependent and different types of responses to temperature were recorded. However, no response patterns to temperature change were found that were consistent for all species or for all halocarbons. We conclude that the production of certain halocarbons may increase with temperature in certain algal species, but that the amount and composition of the volatile halocarbons released by algal communities are probably more affected by temperature-associated species shifts. These results may have implications for climatic change scenarios.

  2. Use of an environmental specimen bank for evaluating the impact of the Prestige oil spill on the levels of trace elements in two species of Fucus on the coast of Galicia (NW Spain).

    PubMed

    Villares, Rubén; Real, Carlos; Fernández, José Angel; Aboal, Jesús; Carballeira, Alejo

    2007-03-15

    In the present study we investigated possible contamination by trace elements due to the oil slick caused by the shipwreck of the Prestige oil tanker, in two species of brown macroalgae (Fucus vesiculosus and Fucus ceranoides) collected from the coastal area most severely affected by the spill (Galicia, NW Spain). The oil slick apparently did not cause significant increases in the concentrations of the trace elements studied, except vanadium. It appears that the magnitude of terrestrial inputs to coastal waters is sufficiently high to mask the inputs of trace elements from the fuel. The observed exception of V suggests that bioaccumulation of this element by the two species of Fucus may be used to indicate exposure to petrochemical products similar to the Prestige fuel. The findings of the study are another example of the importance of the existence of Environmental Specimen Banks for studies of this type.

  3. Biosorption of heavy metals by Fucus spiralis.

    PubMed

    Romera, E; González, F; Ballester, A; Blázquez, M L; Muñoz, J A

    2008-07-01

    The sorption uptake of cadmium, nickel, zinc, copper and lead by marine brown alga Fucus spiralis was investigated in bimetallic, trimetallic and multimetallic solutions. The experimental data fitted very well to Langmuir model. In bimetallic systems, the affinity of biomass for lead and copper increased and the sorption uptake of these metals was not affected by increasing concentrations of cadmium, nickel or zinc. However, in solutions with both metals there was a significant mutual decrease of their sorption levels at high concentrations of the other metal. The sorption uptake of cadmium, nickel and copper was investigated in trimetallic aqueous systems. Based on the kinetic parameter b, the affinity of F. spiralis for copper was considerably higher than for cadmium or nickel: bCd=6.39, bNi=1.82 and bCu=17.89. In all tests, the maximum sorption uptake remained practically constant around 1 mmol/g, indicating that the number of active sites on the biomass was limited. Tests with four and five metals showed that copper was preferentially adsorbed. The differences between the experimental sorption data and those given by the chemical speciation program PHREEQCI were negligible. In general, the software used provided satisfactory estimated data for each metal and hence can be a useful tool to predict or simulate the real process.

  4. A signal peptide secretion screen in Fucus distichus embryos reveals expression of glucanase, EGF domain-containing, and LRR receptor kinase-like polypeptides during asymmetric cell growth.

    PubMed

    Belanger, Kenneth D; Wyman, Aaron J; Sudol, Michelle N; Singla-Pareek, Sneh L; Quatrano, Ralph S

    2003-10-01

    Zygotes of the brown alga Fucus distichus (L.) Powell develop polarity prior to the first embryonic cell division and retain a pattern of asymmetric growth during early embryogenesis. In order to identify F. distichus polypeptides secreted during asymmetric cell growth, we used a functional assay in Saccharomyces cerevisiae to screen a cDNA library generated from asymmetrically growing Fucus embryos for sequences encoding polypeptides that function as signal peptides for secretion. We isolated and sequenced 222 plasmids containing Fucus cDNAs encoding signal peptide activity. The cDNA inserts from these plasmids were translated in silico into 244 potential polypeptide sequences, 169 of which are predicted to contain signal peptides. BlastP analysis of the Fucus sequences revealed similarity between many Fucus proteins and cell surface proteins that function in development in other eukaryotes, including epidermal growth factor (EGF)-like repeat-containing proteins, plant leucine-rich repeat (LRR)-receptor kinases, and algal beta-1, 3-exoglucanase. However, most of the isolated Fucus polypeptides lack similarity to known proteins. The isolation of cDNAs encoding secreted Fucus proteins provides an important step toward characterizing cell surface proteins important for asymmetric organization and growth in fucoid embryos.

  5. Genome and metabolic network of “Candidatus Phaeomarinobacter ectocarpi” Ec32, a new candidate genus of Alphaproteobacteria frequently associated with brown algae

    PubMed Central

    Dittami, Simon M.; Barbeyron, Tristan; Boyen, Catherine; Cambefort, Jeanne; Collet, Guillaume; Delage, Ludovic; Gobet, Angélique; Groisillier, Agnès; Leblanc, Catherine; Michel, Gurvan; Scornet, Delphine; Siegel, Anne; Tapia, Javier E.; Tonon, Thierry

    2014-01-01

    Rhizobiales and related orders of Alphaproteobacteria comprise several genera of nodule-inducing symbiotic bacteria associated with plant roots. Here we describe the genome and the metabolic network of “Candidatus Phaeomarinobacter ectocarpi” Ec32, a member of a new candidate genus closely related to Rhizobiales and found in association with cultures of the filamentous brown algal model Ectocarpus. The “Ca. P. ectocarpi” genome encodes numerous metabolic pathways that may be relevant for this bacterium to interact with algae. Notably, it possesses a large set of glycoside hydrolases and transporters, which may serve to process and assimilate algal metabolites. It also harbors several proteins likely to be involved in the synthesis of algal hormones such as auxins and cytokinins, as well as the vitamins pyridoxine, biotin, and thiamine. As of today, “Ca. P. ectocarpi” has not been successfully cultured, and identical 16S rDNA sequences have been found exclusively associated with Ectocarpus. However, related sequences (≥97% identity) have also been detected free-living and in a Fucus vesiculosus microbiome barcoding project, indicating that the candidate genus “Phaeomarinobacter” may comprise several species, which may colonize different niches. PMID:25120558

  6. Glacial refugia and recolonization pathways in the brown seaweed Fucus serratus.

    PubMed

    Hoarau, G; Coyer, J A; Veldsink, J H; Stam, W T; Olsen, J L

    2007-09-01

    The last glacial maximum (20,000-18,000 years ago) dramatically affected extant distributions of virtually all northern European biota. Locations of refugia and postglacial recolonization pathways were examined in Fucus serratus (Heterokontophyta; Fucaceae) using a highly variable intergenic spacer developed from the complete mitochondrial genome of Fucus vesiculosus. Over 1,500 samples from the entire range of F. serratus were analysed using fluorescent single strand conformation polymorphism. A total of 28 mtDNA haplotypes was identified and sequenced. Three refugia were recognized based on high haplotype diversities and the presence of endemic haplotypes: southwest Ireland, the northern Brittany-Hurd Deep area of the English Channel, and the northwest Iberian Peninsula. The Irish refugium was the source for a recolonization sweep involving a single haplotype via northern Scotland and throughout Scandinavia, whereas recolonization from the Brittany-Hurd Deep refugium was more limited, probably because of unsuitable soft-bottom habitat in the Bay of Biscay and along the Belgian and Dutch coasts. The Iberian populations reflect a remnant refugium at the present-day southern boundary of the species range. A generalized skyline plot suggested exponential population expansion beginning in the mid-Pleistocene with maximal growth during the Eems interglacial 128,000-67,000 years ago, implying that the last glacial maximum mainly shaped population distributions rather than demography.

  7. Sewage derive [sup 15]N in the Baltic traced in fucus

    SciTech Connect

    Hobbie, J.E.; Fry, B. ); Larsson, U.; Elmgren, R. )

    1990-01-09

    Himmerfjarden, a fjord-like bay on the eastern shore of the Baltic, receives treated sewage from 250,000 inhabitants. Because the inorganic N in the effluent is enriched in [sup 15]N through denitrification, nitrification, and ammonia volatilization, an analysis of the distribution of [sup 15]N in the Bay tells how far from the source the sewage nitrogen moves. The attached macroalga Fucus vesiculosus was collected in early May from rocky shore at 0-0.5 m depth and the [sup 15]N content of the tips of the fronds analyzed. This N represents uptake and storage during the previous six months and growth during March and April. The [delta][sup 15]N was uniformly high (11-13[per thousand]) in the main body of the Bay within 15 km from the sewage source. Beyond 15 km values decreased with distance to a low of 4.6[per thousand] at 35 km, where the Bay ends and the coastal waters begin. Using the 11-13 and 4.6[per thousand] as endmembers, the percentage of sewage N making up the Fucus at any point may be calculated. The [delta][sub 15]N of particulate organic matter in the offshore Baltic waters was around 0[per thousand] and Fucus had an [delta][sup 15]N about 1.5[per thousand] higher than the POM. From this and other evidence we conclude that there is a belt of coastal water with an elevated [delta][sup 15]N lying along the east coast of the Baltic. This presumably derives from sewage and perhaps from agriculture and is potentially of use as a tracer of coastal zone/pelagic zone interactions.

  8. Accumulation of silver by Fucus spp. (Phaeophyceae) and its toxicity to Fucus ceranoides under different salinity regimes.

    PubMed

    Ramesh, K; Berry, S; Brown, M T

    2015-08-01

    Metals constitute an important group of abiotic stressors that elicit stress responses in marine algae that include the production of reactive oxygen species (ROS). Silver (Ag) is a highly toxic metal to organisms but despite this there are relatively few studies on how it affects marine macroalgae (seaweeds). In a landmark study published in 1977 the first information was provided on the accumulation of Ag in Fucus spp. (Phaeophyceae) from the Looe estuary, located in south-west England, an area with a long history of mining activity. In the present study, the estuary has been re-visited and the patterns of Ag accumulation in two Fucus spp. and sediment re-examined after 35 years. We conclude that Ag concentrations in sediment and macroalgae from specific sites within the catchment remain high, but more generally sediment concentrations have declined by approximately 65 % and the dissolved, bioavailable fraction by 24 % over this period. In addition, from laboratory studies we provide data on the speciation and toxic effects of Ag under different salinity regimes in the euryhaline brown seaweed, Fucus ceranoides. From these exposure experiments, it was found that with increasing Ag concentrations growth was inhibited and lipid peroxidation associated with ROS production increased. The magnitude of the toxic effects was greater at a salinity of 10 than 28 psu which reflects the greater bioavailability of the toxic species of Ag (Ag(+) and AgCl(0)) at reduced salinities. These findings emphasise the importance of investigating the effects of metal pollution in conjunction with other, natural, environmental stressors such as salinity.

  9. Positive and Negative Effects of Habitat-Forming Algae on Survival, Growth and Intra-Specific Competition of Limpets

    PubMed Central

    Marzinelli, Ezequiel M.; Burrows, Michael T.; Jackson, Angus C.; Mayer-Pinto, Mariana

    2012-01-01

    Understanding the effects of environmental change on the distribution and abundance of strongly interacting organisms, such as intertidal macroalgae and their grazers, needs a thorough knowledge of their underpinning ecological relationships. Control of grazer-plant interactions is bi-directional on northwestern European coasts: grazing by limpets structures populations of macroalgae, while macroalgae provide habitat and food for limpets. Scottish shores dominated by the macroalga Fucus vesiculosus support lower densities and larger sizes of limpets Patella vulgata than shores with less Fucus. These patterns may be due to differences in inter-size-class competitive interactions of limpets among shores with different covers of Fucus. To examine this model, densities of small and large limpets were manipulated in plots with and without Fucus. Amounts of biofilm were measured in each plot. The presence of Fucus increased survival but hindered growth of small (15 mm TL) limpets, which were negatively affected by the presence of large limpets (31 mm TL). In contrast, large limpets were not affected by the presence of Fucus or of small limpets. This suggests the occurrence of asymmetric inter-size-class competition, which was influenced by the presence of macroalgae. Macroalgae and increased densities of limpets did not influence amounts of biofilm. Our findings highlight the role of interactions among organisms in generating ecological responses to environmental change. PMID:23251589

  10. Complete Plastid Genome of the Brown Alga Costaria costata (Laminariales, Phaeophyceae).

    PubMed

    Zhang, Lei; Wang, Xumin; Liu, Tao; Wang, Haiyang; Wang, Guoliang; Chi, Shan; Liu, Cui

    2015-01-01

    Costaria costata is a commercially and industrially important brown alga. In this study, we used next-generation sequencing to determine the complete plastid genome of C. costata. The genome consists of a 129,947 bp circular DNA molecule with an A+T content of 69.13% encoding a standard set of six ribosomal RNA genes, 27 transfer RNA genes, and 137 protein-coding genes with two conserved open reading frames (ORFs). The overall genome structure of C. costata is nearly the same as those of Saccharina japonica and Undaria pinnatifida. The plastid genomes of these three algal species retain a strong conservation of the GTG start codon while infrequently using TGA as a stop codon. In this regard, they differ substantially from the plastid genomes of Ectocarpus siliculosus and Fucus vesiculosus. Analysis of the nucleic acid substitution rates of the Laminariales plastid genes revealed that the petF gene has the highest substitution rate and the petN gene contains no substitution over its complete length. The variation in plastid genes between C. costata and S. japonica is lower than that between C. costata and U. pinnatifida as well as that between U. pinnatifida and S. japonica. Phylogenetic analyses demonstrated that C. costata and U. pinnatifida have a closer genetic relationship. We also identified two gene length mutations caused by the insertion or deletion of repeated sequences, which suggest a mechanism of gene length mutation that may be one of the key explanations for the genetic variation in plastid genomes.

  11. Complete Plastid Genome of the Brown Alga Costaria costata (Laminariales, Phaeophyceae)

    PubMed Central

    Liu, Tao; Wang, Haiyang; Wang, Guoliang; Chi, Shan; Liu, Cui

    2015-01-01

    Costaria costata is a commercially and industrially important brown alga. In this study, we used next-generation sequencing to determine the complete plastid genome of C. costata. The genome consists of a 129,947 bp circular DNA molecule with an A+T content of 69.13% encoding a standard set of six ribosomal RNA genes, 27 transfer RNA genes, and 137 protein-coding genes with two conserved open reading frames (ORFs). The overall genome structure of C. costata is nearly the same as those of Saccharina japonica and Undaria pinnatifida. The plastid genomes of these three algal species retain a strong conservation of the GTG start codon while infrequently using TGA as a stop codon. In this regard, they differ substantially from the plastid genomes of Ectocarpus siliculosus and Fucus vesiculosus. Analysis of the nucleic acid substitution rates of the Laminariales plastid genes revealed that the petF gene has the highest substitution rate and the petN gene contains no substitution over its complete length. The variation in plastid genes between C. costata and S. japonica is lower than that between C. costata and U. pinnatifida as well as that between U. pinnatifida and S. japonica. Phylogenetic analyses demonstrated that C. costata and U. pinnatifida have a closer genetic relationship. We also identified two gene length mutations caused by the insertion or deletion of repeated sequences, which suggest a mechanism of gene length mutation that may be one of the key explanations for the genetic variation in plastid genomes. PMID:26444909

  12. Trophic structure of two intertidal Fucus spp. communities along a vertical gradient: Similarity and seasonal stability evidenced with δ13C and δ15N

    NASA Astrophysics Data System (ADS)

    Bordeyne, François; Davoult, Dominique; Migné, Aline; Bertaud du Chazaud, Euriell; Leroux, Cédric; Riera, Pascal

    2017-02-01

    Intertidal communities dominated by canopy-forming macroalgae typically exhibit some differences in their specific composition that are related to their location along the emersion gradient of rocky shores. Tidal level is also expected to affect resource availability for both primary producers and consumers, potentially leading to divergence in the trophic structure of these communities. Furthermore, in temperate areas, the alternation of seasons has usually a large influence on the primary production and on life-history traits of numerous species, which may induce some changes in the food webs of intertidal communities. Thus, this study aimed to investigate the trophic structure of two intertidal communities located at different tidal levels, over several seasons. Focusing on the dominant species of primary producers and consumers, the food webs of the Fucus vesiculosus Linnaeus and Fucus serratus Linnaeus communities were studied during four successive seasons, using an isotopic (δ13C and δ15N) approach. Due to the diversity of primary producers and consumers living in these two communities, food webs were relatively complex and composed of several trophic pathways. These food webs remained rather conserved over the successive seasons, even though some variability in isotopic signature and in diet has been highlighted for several species. Finally, despite their location at different tidal levels, the two Fucus spp. communities exhibited nearly the same trophic structure, with common consumer species displaying similar isotopic signature in both of them.

  13. In situ determination of trace elements in Fucus spp. by field-portable-XRF.

    PubMed

    Turner, Andrew; Poon, Hiu; Taylor, Alex; Brown, Murray T

    2017-03-23

    Fresh and freeze-dried sample sections of the coastal macroalgae, Fucus serratus and F. vesiculosus, and the brackish water macroalga, F. ceranoides, have been analysed for trace elements by field-portable-X-ray fluorescence (FP-XRF) spectrometry using a Niton XL3t in a low density mode with thickness correction. When analysed fresh in a laboratory accessory stand for a period of 200 seconds, As, Br, Fe and Zn were registered in the apex, mid-frond and lower stipe of all species, with detection limits of a few μg g(-1) (As) or a few tens of μg g(-1) (Br, Fe, Zn); when analysed dry under the same conditions, concentrations returned were systematically higher and Cu and Pb were detected in a number of F. ceranoides sections. Concentrations arising from both approaches on a dry weight basis were highly correlated, with deviations from unit slope attributed to the absorption of fluorescent X-rays by internal and surficial water when analysed fresh. With algorithms correcting for the effects of water on mass and X-ray absorption, sections of F. vesiculosus and F. ceranoides were analysed in situ with the XRF connected to a mobile stand and laptop. Dry weight concentrations returned for As and Zn were significantly correlated with respective concentrations subsequently determined by ICP-MS following acid digestion and with a slope close to unity; lower concentrations of Fe returned by ICP were attributed to the incomplete acid digestion of silt particles that evaded an initial cleaning step, while Br concentrations could not be verified independently because of loss of volatile forms during digestion. The in situ determination of trace elements in fucoids by FP-XRF provides a rapid and non-destructive means of monitoring environmental quality and identifying hot-spots of contamination, and enables a research strategy to be developed iteratively that is informed by immediate results.

  14. Early embryo development in Fucus distichus is auxin sensitive

    NASA Technical Reports Server (NTRS)

    Basu, Swati; Sun, Haiguo; Brian, Leigh; Quatrano, Ralph L.; Muday, Gloria K.

    2002-01-01

    Auxin and polar auxin transport have been implicated in controlling embryo development in land plants. The goal of these studies was to determine if auxin and auxin transport are also important during the earliest stages of development in embryos of the brown alga Fucus distichus. Indole-3-acetic acid (IAA) was identified in F. distichus embryos and mature tissues by gas chromatography-mass spectroscopy. F. distichus embryos accumulate [(3)H]IAA and an inhibitor of IAA efflux, naphthylphthalamic acid (NPA), elevates IAA accumulation, suggesting the presence of an auxin efflux protein complex similar to that found in land plants. F. distichus embryos normally develop with a single unbranched rhizoid, but growth on IAA leads to formation of multiple rhizoids and growth on NPA leads to formation of embryos with branched rhizoids, at concentrations that are active in auxin accumulation assays. The effects of IAA and NPA are complete before 6 h after fertilization (AF), which is before rhizoid germination and cell division. The maximal effects of IAA and NPA are between 3.5 and 5 h AF and 4 and 5.5 h AF, respectively. Although, the location of the planes of cell division was significantly altered in NPA- and IAA-treated embryos, these abnormal divisions occurred after abnormal rhizoid initiation and branching was observed. The results of this study suggest that auxin acts in the formation of apical basal patterns in F. distichus embryo development.

  15. Box-Behnken methodology for Cr (VI) and leather dyes removal by an eco-friendly biosorbent: F. vesiculosus.

    PubMed

    Cobas, M; Sanromán, M A; Pazos, M

    2014-05-01

    This study focused on leather industrial effluents treatment by biosorption using Fucus vesiculosus as low-cost adsorbent. These effluents are yellowish-brown color and high concentration of Cr (VI). Therefore, biosorption process was optimized using response surface methodology based on Box-Behnken design operating with a simulated leather effluent obtained by mixture of Cr (VI) solution and four leather dyes. The key variables selected were initial solution pH, biomass dosage and CaCl2 concentration in the pretreatment stage. The statistical analysis shows that pH has a negligible effect, being the biomass dosage and CaCl2 concentration the most significant variables. At optimal conditions, 98% of Cr (VI) and 88% of dyes removal can be achieved. Freundlich fitted better to the obtained equilibrium data for all studied systems than Temkin, Langmuir or D-R models. In addition, the use of the final biosorbent as support-substrate to grown of enzyme producer fungi, Pleurotus ostreatus, was also demonstrated.

  16. Parallel speciation or long-distance dispersal? Lessons from seaweeds (Fucus) in the Baltic Sea.

    PubMed

    Pereyra, R T; Huenchuñir, C; Johansson, D; Forslund, H; Kautsky, L; Jonsson, P R; Johannesson, K

    2013-08-01

    Parallel evolution has been invoked as a forceful mechanism of ecotype and species formation in many animal taxa. However, parallelism may be difficult to separate from recently monophyletically diverged species that are likely to show complex genetic relationships as a result of considerable shared ancestral variation and secondary hybridization in local areas. Thus, species' degrees of reproductive isolation, barriers to dispersal and, in particular, limited capacities for long-distance dispersal will affect demographical structures underlying mechanisms of divergent evolution. Here, we used nine microsatellite DNA markers to study intra- and interspecific genetic diversity of two recently diverged species of brown macroalgae, Fucus radicans (L. Bergström & L. Kautsky) and F. vesiculosus (Linnaeus), in the Baltic Sea. We further performed biophysical modelling to identify likely connectivity patterns influencing the species' genetic structures. For each species, we found intraspecific contrasting patterns of clonality incidence and population structure. In addition, strong genetic differentiation between the two species within each locality supported the existence of two distinct evolutionary lineages (FST  = 0.15-0.41). However, overall genetic clustering analyses across both species' populations revealed that all populations from one region (Estonia) were more genetically similar to each other than to their own taxon from the other two regions (Sweden and Finland). Our data support a hypothesis of parallel speciation. Alternatively, Estonia may be the ancestral source of both species, but is presently isolated by oceanographic barriers to dispersal. Thus, a limited gene flow in combination with genetic drift could have shaped the seemingly parallel structure.

  17. Fucoidan extracted from Fucus evanescens prevents endotoxin-induced damage in a mouse model of endotoxemia.

    PubMed

    Kuznetsova, Tatyana A; Besednova, Natalya N; Somova, Larisa M; Plekhova, Natalya G

    2014-01-31

    An important problem of treating patients with endotoxemia is to find drugs to reduce the negative effects of endotoxin on the organism. We tested fucoidan (sulfated polysaccharide) from the brown alga Fucus evanescens as a potential drug in a mouse model of endotoxemia inducted by lipopolysaccharide (LPS). The survival time of mice injected with LPS increased under fucoidan treatment compared with the group of mice injected with LPS only. The preventive administration of fucoidan to mice with endotoxemia resulted in inhibition of increased levels of proinflammatory cytokines (TNFα and IL-6), as well as decreasing of the processes of hypercoagulability. The parenteral or per os administration of fucoidan resulted in decreasing the degree of microcirculatory disorders and secondary dystrophic-destructive changes in parenchymal organs of mice with endotoxemia. Taken together, these results demonstrate that fucoidan prevents endotoxin-induced damage in a mouse model of endotoxemia and increases the mice's resistance to LPS.

  18. Ca2+ and Calmodulin Dynamics during Photopolarization in Fucus serratus Zygotes.

    PubMed Central

    Love, J.; Brownlee, C.; Trewavas, A. J.

    1997-01-01

    The role of Ca2+ in zygote polarization in fucoid algae (Fucus, Ascophyllum, and Pelvetia species) zygote polarization is controversial. Using a local source of Fucus serratus, we established that zygotes form a polar axis relative to unilateral light (photopolarization) between 8 and 14 h after fertilization (AF), and become committed to this polarity at approximately 15 to 18 h AF. We investigated the role of Ca2+, calmodulin, and actin during photopolarization by simultaneously exposing F. serratus zygotes to polarizing light and various inhibitors. Neither removal of Ca2+ from the culture medium or high concentrations of EGTA and LaCl3 had any effect on photopolarization. Bepridil, 3,4,5-trimethoxybenzoic acid 8-(diethylamino) octyl ester, nifedipine, and verapamil, all of which block intracellular Ca2 release, reduced photopolarization from 75 to 30%. The calmodulin antagonists N-(6-aminohexyl)-5-chloro-L-naphthalenesulfonamide and trifluoperazine inhibited photopolarization in all zygotes, whereas N-(6-aminohexyl)-L-naphthalenesulfonamide had no effect. Cytochalasin B, cytochalasin D, and latrunculin B, all of which inhibit actin polymerization, had no effect on photopolarization, but arrested polar axis fixation. The role of calmodulin during polarization was investigated further. Calmodulin mRNA from the closely related brown alga Macrocystis pyrifera was cloned and the protein was expressed in bacteria. Photopolarization was enhanced following microinjections of this recombinant calmodulin into developing zygotes. Confocal imaging of fluorescein isothiocyanate-labeled recombinant calmodulin in photopolarized zygotes showed a homogenous signal distribution at 13 h AF, which localized to the presumptive rhizoid site at 15 h AF. PMID:12223805

  19. Larvicidal algae.

    PubMed

    Marten, Gerald G

    2007-01-01

    Although most algae are nutritious food for mosquito larvae, some species kill the larvae when ingested in large quantities. Cyanobacteria (blue-green algae) that kill larvae do so by virtue of toxicity. While blue-green algae toxins may offer possibilities for delivery as larvicides, the toxicity of live blue-green algae does not seem consistent enough for live algae to be useful for mosquito control. Certain species of green algae in the order Chlorococcales kill larvae primarily because they are indigestible. Where these algae are abundant in nature, larvae consume them to the exclusion of other food and then starve. Under the right circumstances, it is possible to introduce indigestible algae into a breeding habitat so they become abundant enough to render it unsuitable for mosquito production. The algae can persist for years, even if the habitat dries periodically. The main limitation of indigestible algae lies in the fact that, under certain conditions, they may not replace all the nutritious algae in the habitat. More research on techniques to ensure complete replacement will be necessary before indigestible algae can go into operational use for mosquito control.

  20. Stress ecology in fucus: abiotic, biotic and genetic interactions.

    PubMed

    Wahl, Martin; Jormalainen, Veijo; Eriksson, Britas Klemens; Coyer, James A; Molis, Markus; Schubert, Hendrik; Dethier, Megan; Karez, Rolf; Kruse, Inken; Lenz, Mark; Pearson, Gareth; Rohde, Sven; Wikström, Sofia A; Olsen, Jeanine L

    2011-01-01

    Stress regimes defined as the synchronous or sequential action of abiotic and biotic stresses determine the performance and distribution of species. The natural patterns of stress to which species are more or less well adapted have recently started to shift and alter under the influence of global change. This was the motivation to review our knowledge on the stress ecology of a benthic key player, the macroalgal genus Fucus. We first provide a comprehensive review of the genus as an ecological model including what is currently known about the major lineages of Fucus species with respect to hybridization, ecotypic differentiation and speciation; as well as life history, population structure and geographic distribution. We then review our current understanding of both extrinsic (abiotic/biotic) and intrinsic (genetic) stress(es) on Fucus species and how they interact with each other. It is concluded that (i) interactive stress effects appear to be equally distributed over additive, antagonistic and synergistic categories at the level of single experiments, but are predominantly additive when averaged over all studies in a meta-analysis of 41 experiments; (ii) juvenile and adult responses to stress frequently differ and (iii) several species or particular populations of Fucus may be relatively unaffected by climate change as a consequence of pre-adapted ecotypes that collectively express wide physiological tolerences. Future research on Fucus should (i) include additional species, (ii) include marginal populations as models for responses to environmental stress; (iii) assess a wider range of stress combinations, including their temporal fluctuations; (iv) better differentiate between stress sensitivity of juvenile versus adult stages; (v) include a functional genomic component in order to better integrate Fucus' ecological and evolutionary responses to stress regimes and (vi) utilize a multivariate modelling approach in order to develop and understand interaction

  1. The Study of Algae

    ERIC Educational Resources Information Center

    Rushforth, Samuel R.

    1977-01-01

    Included in this introduction to the study of algae are drawings of commonly encountered freshwater algae, a summary of the importance of algae, descriptions of the seven major groups of algae, and techniques for collection and study of algae. (CS)

  2. Algae Resources

    SciTech Connect

    2016-06-01

    Algae are highly efficient at producing biomass, and they can be found all over the planet. Many use sunlight and nutrients to create biomass, which contain key components—including lipids, proteins, and carbohydrates— that can be converted and upgraded to a variety of biofuels and products. A functional algal biofuels production system requires resources such as suitable land and climate, sustainable management of water resources, a supplemental carbon dioxide (CO2) supply, and other nutrients (e.g., nitrogen and phosphorus). Algae can be an attractive feedstock for many locations in the United States because their diversity allows for highpotential biomass yields in a variety of climates and environments. Depending on the strain, algae can grow by using fresh, saline, or brackish water from surface water sources, groundwater, or seawater. Additionally, they can grow in water from second-use sources such as treated industrial wastewater; municipal, agricultural, or aquaculture wastewater; or produced water generated from oil and gas drilling operations.

  3. Marine plants may polarize remote Fucus eggs via luminescence.

    PubMed

    Jaffe, Lionel F

    2005-01-01

    Fucus zygotes can be polarized by many environmental vectors. These include those created by pieces of all the intertidal marine plants tested. At distances of up to 5-10 mm away from such pieces, Fucus zygotes form their intitial outgrowths or germinate towards them. Earlier papers had inferred that this so-called 'thallus effect' is mediated by diffusing molecules. The present reinvestigation indicates that the thallus effect is exerted by influences that can go right through glass barriers. This indicates action via luminescence. This luminescence may come from bacteria growing in biofilms on the similar surfaces of these otherwise unrelated source plants. Moreover, this directive luminescence is inferred to lie at wavelengths in the red or longer and may take the form of more or less coherent biophotons.

  4. Adaptation to high light irradiances enhances the photosynthetic Cu2+ resistance in Cu2+ tolerant and non-tolerant populations of the brown macroalgae Fucus serratus.

    PubMed

    Nielsen, Hanne Dalsgaard; Nielsen, Søren Laurentius

    2010-05-01

    The relationship between light acclimation and Cu(2+) tolerance was studied in two populations of Fucus serratus known to be naturally non-tolerant and tolerant to Cu(2+). Acclimation to high irradiances increased the photosynthetic tolerance to Cu(2+). The xanthophyll cycle was apparently not involved in protecting the photosynthetic apparatus against Cu(2+) toxicity, as results showed that Cu(2+) did not induce dynamic photoinhibition. The higher photosynthetic Cu(2+) resistance of high light algae did not result in increased growth. The excess energy acquired by high light-adapted algae appeared to be utilized in Cu(2+) defense mechanisms in the Cu(2+) non-tolerant population. The polyphenol content of the algae was reciprocal to the Cu(T) content, suggesting that polyphenol may be the primary Cu(2+) defense of non-tolerant low light algae, acting through secretion and extracellular chelating of Cu(2+), while the compounds do not seem to be involved in the primary Cu(2+) tolerance mechanism in Cu(2+) tolerant algae.

  5. Cell cycle-dependent control of polarised development by a cyclin-dependent kinase-like protein in the Fucus zygote.

    PubMed

    Corellou, F; Brownlee, C; Kloareg, B; Bouget, F Y

    2001-11-01

    Although iterative development can be uncoupled from morphogenesis in plant organs, the relationship between the cell cycle and developmental events is not well established in embryos. Zygotes of fucoid algae, including Fucus and Pelvetia are particularly well suited for studying the interaction(s) between cell cycle progression and the early morphogenetic events, as the establishment of polarity and its morphogenetic expression, i.e. germination, and the first cell cycle are concomitant. We have previously demonstrated that, in Fucus zygotes, various aspects of cell cycle progression are tightly controlled by cyclin-dependent kinase (CDK)-like proteins, including two PSTAIRE CDK-like proteins, p34 and p32, which are synthesised after fertilisation. We show that specific inhibition of CDK-like proteins, either with purine derivatives such as olomoucine and amino-purvalanol or by microinjection of the CDK inhibitor p21(cip1), prevents germination and cell division. Whereas direct inhibition of DNA replication by aphidicolin did not affect polarised development, olomoucine, which has previously been shown to prevent entry in S phase, and other purine derivatives also inhibited photopolarisation. Early microinjection of a monoclonal anti-PSTAIRE antibody also prevented germination and cell division. Only p34 had affinity for amino-purvalanol, suggesting that among PSTAIRE CDKs, this protein is the main target of purine derivatives. Models to account for the simultaneous control of early cell cycle progression and polarisation are proposed.

  6. Biosorption of Cu(II) from aqueous solution by Fucus serratus: surface characterization and sorption mechanisms.

    PubMed

    Ahmady-Asbchin, Salman; Andrès, Yves; Gérente, Claire; Cloirec, Pierre Le

    2008-09-01

    In this work, the brown alga Fucus serratus (FS) used as a low cost sorbent has been studied for the biosorption of copper(II) ions in batch reactors. Firstly, the characterization of the surface functional groups was performed with two methods: a qualitatively analysis with the study of FT-IR spectrum and a quantitatively determination with potentiometric titrations. From this latter, a total proton exchange capacity of 3.15 mmolg(-1) was extrapolated from the FS previously protonated. This value was similar to the total acidity of 3.56 mmolg(-1) deduced from the Gran method. Using the single extrapolation method, three kinds of acidic functional groups with three intrinsic pK(a) were determined at 3.5, 8.2 and 9.6. The point of zero net proton charge (PZNPC) was found close to pH 6.3. Secondly, the biosorption of copper ions was studied. The equilibrium time was about 350 min and the adsorption equilibrium data were well described by the Langmuir's equation. The maximum adsorption capacity has been extrapolated to 1.60 mmolg(-1). The release of calcium and magnesium ions was also measured in relation to the copper biosorption. Finally, the efficiency of this biosorbent in natural tap water for the removal of copper was also investigated. All these observations indicate that the copper biosorption on FS is mainly based on ion exchange mechanism and this biomass could be then a suitable sorbent for the removal of heavy metals from wastewaters.

  7. Being abundant is not enough: a decrease in effective population size over eight generations in a Norwegian population of the seaweed, Fucus serratus.

    PubMed

    Coyer, James A; Hoarau, Galice; Sjøtun, Kjersti; Olsen, Jeanine L

    2008-12-23

    The brown alga Fucus serratus is a key foundation species on rocky intertidal shores of northern Europe. We sampled the same population off the coast of southern Norway in 2000 and 2008, and using 26 microsatellite loci, we estimated the changes in genetic diversity and effective population size (Ne). The unexpectedly low Ne (73-386) and Ne/N ratio (10-3-10-4), in combination with a significant decrease (14%) in allelic richness over the 8-year period, suggests an increased local extinction risk. If small Ne proves to be a common feature of F. serratus, then being abundant may not be enough for the species to weather future environmental changes.

  8. [Morphofunctional changes of dendritic cells induced by sulfated polysaccharides of brown algae].

    PubMed

    Makarenkova, I D; Akhmatova, N K; Ermakova, S P; Besednova, N N

    2017-01-01

    The effects of various sulfated polysaccharides of brown algae Fucus evanescens, Saccharina cichorioides and Saccharina japonica on the morphofunctional changes of dendritic cells have been investigated using flow cytometry and phase-contrast microscopy. The dendritic cells are characterized by larger sizes, vacuolated cytoplasm, eccentrically located nucleus, and also by the presence of numerous cytoplasmic pseudopodia of various shapes. They express surface markers, indicating their maturation (CD83, CD11c, HLA-DR, CD86). Increased production of immunoregulatory (IL-12) and proinflammatory TNF-a, IL-6) cytokines (by dendritic cells polarizes the development of the Th-1 type immune response.

  9. Magnetic separation of algae

    SciTech Connect

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  10. Alkaloids in Marine Algae

    PubMed Central

    Güven, Kasım Cemal; Percot, Aline; Sezik, Ekrem

    2010-01-01

    This paper presents the alkaloids found in green, brown and red marine algae. Algal chemistry has interested many researchers in order to develop new drugs, as algae include compounds with functional groups which are characteristic from this particular source. Among these compounds, alkaloids present special interest because of their pharmacological activities. Alkaloid chemistry has been widely studied in terrestrial plants, but the number of studies in algae is insignificant. In this review, a detailed account of macro algae alkaloids with their structure and pharmacological activities is presented. The alkaloids found in marine algae may be divided into three groups: 1. Phenylethylamine alkaloids, 2. Indole and halogenated indole alkaloids, 3. Other alkaloids. PMID:20390105

  11. Cell cycle in the fucus zygote parallels a somatic cell cycle but displays a unique translational regulation of cyclin-dependent kinases.

    PubMed

    Corellou, F; Brownlee, C; Detivaud, L; Kloareg, B; Bouget, F Y

    2001-03-01

    In eukaryotic cells, the basic machinery of cell cycle control is highly conserved. In particular, many cellular events during cell cycle progression are controlled by cyclin-dependent kinases (CDKs). The cell cycle in animal early embryos, however, differs substantially from that of somatic cells or yeasts. For example, cell cycle checkpoints that ensure that the sequence of cell cycle events is correct have been described in somatic cells and yeasts but are largely absent in embryonic cells. Furthermore, the regulation of CDKs is substantially different in the embryonic and somatic cells. In this study, we address the nature of the first cell cycle in the brown alga Fucus, which is evolutionarily distant from the model systems classically used for cell cycle studies in embryos. This cycle consists of well-defined G1, S, G2, and M phases. The purine derivative olomoucine inhibited CDKs activity in vivo and in vitro and induced different cell cycle arrests, including at the G1/S transition, suggesting that, as in somatic cells, CDKs tightly control cell cycle progression. The cell cycle of Fucus zygotes presented the other main features of a somatic cell cycle, such as a functional spindle assembly checkpoint that targets CDKs and the regulation of the early synthesis of two PSTAIRE CDKs, p32 and p34, and the associated histone H1 kinase activity as well as the regulation of CDKs by tyrosine phosphorylation. Surprisingly, the synthesis after fertilization of p32 and p34 was translationally regulated, a regulation not described previously for CDKs. Finally, our results suggest that the activation of mitotic CDKs relies on an autocatalytic amplification mechanism.

  12. Seasonal fluctuations in macrobenthic fauna of the Fucus belt in kiel fjord (western baltic sea)

    NASA Astrophysics Data System (ADS)

    Anders, K.; Möller, H.

    1983-09-01

    The macrobenthic fauna associated with Fucus at a station in the Kiel Fjord was investigated from June 1978 until June 1979. The predominant group in number as well as in biomass were gammarids. They formed, together with the isopods Idotea spp., approximately 95 % of the total average annual biomass. The total dry weight of all macrobenthic animals (excl. Littorina spp.) increased from 1.9 g per kg Fucus in May to about 16 g in June August, and dropped to 8.3 g in September. Winter average dry weight values were only about 6 % of the summer values.

  13. Algae Derived Biofuel

    SciTech Connect

    Jahan, Kauser

    2015-03-31

    One of the most promising fuel alternatives is algae biodiesel. Algae reproduce quickly, produce oils more efficiently than crop plants, and require relatively few nutrients for growth. These nutrients can potentially be derived from inexpensive waste sources such as flue gas and wastewater, providing a mutual benefit of helping to mitigate carbon dioxide waste. Algae can also be grown on land unsuitable for agricultural purposes, eliminating competition with food sources. This project focused on cultivating select algae species under various environmental conditions to optimize oil yield. Membrane studies were also conducted to transfer carbon di-oxide more efficiently. An LCA study was also conducted to investigate the energy intensive steps in algae cultivation.

  14. A MOLECULAR PHYLOGENY OF ACROCHAETE AND OTHER ENDOPHYTIC GREEN ALGAE (ULVALES, CHLOROPHYTA)(1).

    PubMed

    Rinkel, Barbara E; Hayes, Paul; Gueidan, Cécile; Brodie, Juliet

    2012-08-01

    A molecular phylogeny was reconstructed from a culture collection of >150 isolates of epi-endophytic and endophytic green algae, based on nucleotide sequences of the plastid tufA and nuclear ITS2 loci. The cultures were isolated from a variety of algal hosts, notably the red algae Chondrus crispus, Mastocarpus stellatus, and Osmundea species, and the brown algae Chorda filum and Fucus serratus. The phylogeny revealed that in the Ulvales the majority of isolates fell into Acrochaete (Ulvellaceae), Ulva (Ulvaceae), Bolbocoleon (Bolbocoleaceae), and at least two unknown genera provisionally assigned to the Kornmanniaceae. Acrochaete was monophyletic. The genus was also more specious than previously described with 12 species, including up to six new species awaiting formal description. Isolates identified as Acrochaete repens, the type species of the genus, were polyphyletic. The remainder of the isolates were placed in the Ulotrichales. The results confirm that the endophytic habit supports a broad diversity of algal taxa and suggest that blade formation is a relatively recent innovation within the green algae.

  15. Genomic scans detect signatures of selection along a salinity gradient in populations of the intertidal seaweed Fucus serratus on a 12 km scale.

    PubMed

    Coyer, J A; Hoarau, G; Pearson, G; Mota, C; Jüterbock, A; Alpermann, T; John, U; Olsen, J L

    2011-03-01

    Detecting natural selection in wild populations is a central challenge in evolutionary biology and genomic scans are an important means of detecting allele frequencies that deviate from neutral expectations among marker loci. We used nine anonymous and 15 EST-linked microsatellites, 362 AFLP loci, and several neutrality tests, to identify outlier loci when comparing four populations of the seaweed Fucus serratus spaced along a 12km intertidal shore with a steep salinity gradient. Under criteria of at least two significant tests in at least two population pairs, three EST-derived and three anonymous loci revealed putative signatures of selection. Anonymous locus FsB113 was a consistent outlier when comparing least saline to fully marine sites. Locus F37 was an outlier when comparing the least saline to more saline areas, and was annotated as a polyol transporter/putative mannitol transporter - an important sugar-alcohol associated with osmoregulation by brown algae. The remaining loci could not be annotated using six different data bases. Exclusion of microsatellite outlier loci did not change either the degree or direction of differentiation among populations. In one outlier test, the number of AFLP outlier loci increased as the salinity differences between population pairs increased (up to 14); only four outliers were detected with the second test and only one was consistent with both tests. Consistency may be improved with a much more rigorous approach to replication and/or may be dependent upon the class of marker used.

  16. Different speciation for bromine in brown and red algae, revealed by in vivo X-ray absorption spectroscopic studies.

    PubMed

    Küpper, Frithjof C; Leblanc, Catherine; Meyer-Klaucke, Wolfram; Potin, Philippe; Feiters, Martin C

    2014-08-01

    Members of various algal lineages are known to be strong producers of atmospherically relevant halogen emissions, that is a consequence of their capability to store and metabolize halogens. This study uses a noninvasive, synchrotron-based technique, X-ray absorption spectroscopy, for addressing in vivo bromine speciation in the brown algae Ectocarpus siliculosus, Ascophyllum nodosum, and Fucus serratus, the red algae Gracilaria dura, G. gracilis, Chondrus crispus, Osmundea pinnatifida, Asparagopsis armata, Polysiphonia elongata, and Corallina officinalis, the diatom Thalassiosira rotula, the dinoflagellate Lingulodinium polyedrum and a natural phytoplankton sample. The results highlight a diversity of fundamentally different bromine storage modes: while most of the stramenopile representatives and the dinoflagellate store mostly bromide, there is evidence for Br incorporated in nonaromatic hydrocarbons in Thalassiosira. Red algae operate various organic bromine stores - including a possible precursor (by the haloform reaction) for bromoform in Asparagopsis and aromatically bound Br in Polysiphonia and Corallina. Large fractions of the bromine in the red algae G. dura and C. crispus and the brown alga F. serratus are present as Br(-) defects in solid KCl, similar to what was reported earlier for Laminaria parts. These results are discussed according to different defensive strategies that are used within algal taxa to cope with biotic or abiotic stresses.

  17. Hybridization and introgression in a mixed population of the intertidal seaweeds Fucus evanescens and F. serratus.

    PubMed

    Coyer, J A; Hoarau, G; Stam, W T; Olsen, J L

    2007-11-01

    The introduced Fucus evanescens (hermaphroditic) and the native F. serratus (dioecious) have been in secondary contact along the Danish coast of the Kattegat Sea for 60-100 years and dioecious hybrids have been observed at Blushøj for several years. Hybridization in Fucus is unusual because it appears to always involve a hermaphroditic and a dioecious parental pair. We determined the degree and spatial patterns of introgression for 286 individuals using 10 microsatellite loci and cpDNA. Hybrids accounted for nearly 13% of the population, yet parental species were well differentiated (F(ST) = 0.633). The presence of F. evanescens chloroplasts in 100% of F(1) hybrids revealed asymmetrical hybridization. Fucus evanescens cpDNA was observed in 50% of introgressed and 5.4% of pure F. serratus, but no F. serratus cpDNA was found in F. evanescens. In contrast, nuclear DNA introgression was symmetrical with an equal amount ( approximately 1.5%) of genes introgressed into each parental species. Survivorship and viability data suggest selection against hybrids in the hybrid zone.

  18. Hybridization of the marine seaweeds, Fucus serratus and Fucus evanescens (Heterokontophyta: Phaeophyceae) in a 100-year-old zone of secondary contact.

    PubMed Central

    Coyer, J A; Peters, A F; Hoarau, G; Stam, W T; Olsen, J L

    2002-01-01

    Historically, the intertidal seaweeds Fucus serratus (Fs) and Fucus evanescens (Fe) were sympatric only along the western coast of Norway. In the mid-1890s, Fe (monoecious) was accidentally introduced into the Oslofjord. Putative hybridization with the endemic Fs (dioecious) was observed in Oslofjord by 1977 and in the Kattegat and western Baltic Seas by 1998. At Blushøj, Denmark (Kattegat Sea) putative Fs x Fe hybrids were present only when densities of Fe and Fs exceeded 14 and 2 m(-2), respectively. All of the 58 putative hybrids that were collected in 1999 were dioecious and intermediate in morphology. Essentially all (57 out of 58) were reproductively mature, but the oogonia possessed fewer and more variably sized eggs than either parent. Examination of each parental species and putative hybrids with nuclear, mitochondrial and chloroplast molecular markers confirmed the occurrence of hybridization. Furthermore, all of the hybrids possessed Fe-type chloroplasts and mitochondria, indicating that only the Fe egg x Fs sperm pairing was successful in the field. The reciprocal cross of Fs egg x Fe sperm was absent in the field and significantly less successful in laboratory crossings. Asymmetrical hybridization has also been reported for several species of plants and animals. PMID:12350271

  19. Genomics of Volvocine Algae

    PubMed Central

    Umen, James G.; Olson, Bradley J.S.C.

    2015-01-01

    Volvocine algae are a group of chlorophytes that together comprise a unique model for evolutionary and developmental biology. The species Chlamydomonas reinhardtii and Volvox carteri represent extremes in morphological diversity within the Volvocine clade. Chlamydomonas is unicellular and reflects the ancestral state of the group, while Volvox is multicellular and has evolved numerous innovations including germ-soma differentiation, sexual dimorphism, and complex morphogenetic patterning. The Chlamydomonas genome sequence has shed light on several areas of eukaryotic cell biology, metabolism and evolution, while the Volvox genome sequence has enabled a comparison with Chlamydomonas that reveals some of the underlying changes that enabled its transition to multicellularity, but also underscores the subtlety of this transition. Many of the tools and resources are in place to further develop Volvocine algae as a model for evolutionary genomics. PMID:25883411

  20. Modification of algae with zinc, copper and silver ions for usage as natural composite for antibacterial applications.

    PubMed

    Mahltig, B; Soltmann, U; Haase, H

    2013-03-01

    Nanometer sized metal particles are used in many applications as antimicrobial materials. However in public discussion nanoparticular materials are a matter of concern due to potential health risks. Hence there is a certain demand for alternative antimicrobial acting materials. For this, the aim of this work is to realize an antimicrobial active material based on the release of metal ions from a natural depot. By this, the use of elemental metal particles or metal oxide particles in nanometer or micrometer scale is avoided. As natural depot four different algae materials (gained from Ascophyllum nodosum, Fucus vesicolosus, Spirulina platensis and Nannochloropsis) are used and loaded by bioabsorption with metal ions Ag(+), Cu(2+) and Zn(2+). The amount of metal bound by biosorption differs strongly in the range of 0.8 to 5.4 mg/g and depends on type of investigated algae material and type of metal ion. For most samples a smaller release of biosorbed Ag(+) and Cu(2+) is observed compared to a strong release of Zn(2+). The antibacterial activity of the prepared composites is investigated with Escherichia coli. Algae material without biosorbed metal has only a small effect on E. coli. Also by modification of algae with Zn(2+) only a small antibacterial property can be observed. Only with biosorption of Ag(+), the algae materials gain a strong bactericidal effect, even in case of a small amount of released silver ions. These silver modified algae materials can be used as highly effective bactericidal composites which may be used in future applications for the production of antimicrobial textiles, papers or polymer materials.

  1. Characterization of vanadium bromoperoxidase from Macrocystis and Fucus: reactivity of vanadium bromoperoxidase toward acyl and alkyl peroxides and bromination of amines.

    PubMed

    Soedjak, H S; Butler, A

    1990-08-28

    Vanadium bromoperoxidase (V-BrPO) has been isolated and purified from the marine brown algae Fucus distichus and Macrocystis pyrifera. V-BrPO catalyzes the oxidation of bromide by hydrogen peroxide, resulting in the bromination of certain organic acceptors or the formation of dioxygen. V-BrPO from F. distichus and M. pyrifera have subunit molecular weights of 65,000 and 74,000, respectively, and specific activities of 1580 units/mg (pH 6.5) and 1730 units/mg (pH 6) for the bromination of monochlorodimedone, respectively. As isolated, the enzymes contain a substoichiometric vanadium/subunit ratio; the vanadium content and specific activity are increased by addition of vanadate. V-BrPO (F. distichus, M. pyrifera, and Ascophyllum nodosum) also catalyzes the oxidation of bromide using peracetic acid. In the absence of an organic acceptor, a mixture of oxidized bromine species (e.g., hypobromous acid, bromine, and tribromide) is formed. Bromamine derivatives are formed from the corresponding amines, while 5-bromocytosine is formed from cytosine. In all cases, the rate of the V-BrPO-catalyzed reaction is much faster than that of the uncatalyzed oxidation of bromide by peracetic acid, at pH 8.5, 1 mM bromide, and 2 mM peracetic acid. In contrast to hydrogen peroxide, V-BrPO does not catalyze formation of dioxygen from peracetic acid in either the presence or absence of bromide. V-BrPO also uses phenylperacetic acid, m-chloroperoxybenzoic acid, and p-nitroperoxybenzoic acid to catalyze the oxidation of bromide; dioxygen is not formed with these peracids. V-BrPO does not catalyze bromide oxidation or dioxygen formation with the alkyl peroxides ethyl hydroperoxide, tert-butyl hydroperoxide, and cuminyl hydroperoxide.

  2. Determination of threshold concentrations of metals in indicator algae of coastal waters in the northwest Sea of Japan

    NASA Astrophysics Data System (ADS)

    Chernova, E. N.; Kozhenkova, S. I.

    2016-05-01

    Background concentrations of Fe, Mn, Cu, Zn, Pb, Cd, and Ni were calculated for thalli of abundant algae of Fucus, Silvetia, Sargassum, Cystoseira spp. from the northwest Sea of Japan during 1987-2008. As the upper threshold levels of metal background concentrations, the median values plus double medians of absolute deviations from the medians were used (Me + 2MAD). The lower threshold level of the background concentration equal to the physiological need for an element is the median of 15% minimum values in the sampling minus the double median of absolute deviations from the median (Me15-2MAD15). The range of Me15 ± 2MAD15 is considered the natural background range of concentrations.

  3. Formosa algae gen. nov., sp. nov., a novel member of the family Flavobacteriaceae.

    PubMed

    Ivanova, Elena P; Alexeeva, Yulia V; Flavier, Sébastien; Wright, Jonathan P; Zhukova, Natalia V; Gorshkova, Natalia M; Mikhailov, Valery V; Nicolau, Dan V; Christen, Richard

    2004-05-01

    Four light-yellow-pigmented, Gram-negative, short-rod-shaped, non-motile isolates were obtained from enrichment culture during degradation of the thallus of the brown alga Fucus evanescens. The isolates studied were chemo-organotrophic, alkalitolerant and mesophilic. Polar lipids were analysed and phosphatidylethanolamine was the only phospholipid identified. The predominant cellular fatty acids were 15 : 0, i15 : 0, ai15 : 0, i15 : 1 and 15 : 1(n-6). The DNA G+C contents of the four strains were 34.0-34.4 mol%. The level of DNA relatedness of the four isolates was conspecific (88-98 %), indicating that they belong to the same species. The 16S rDNA sequence of strain KMM 3553(T) was determined. Phylogenetic analysis revealed that KMM 3553(T) formed a distinct phyletic line in the phylum Bacteroidetes, class Flavobacteria in the family Flavobacteriaceae and that, phylogenetically, this strain could be placed almost equidistant from the genera Gelidibacter and Psychroserpens (16S rRNA gene sequence similarities of 94 %). On the basis of significant differences in phenotypic and chemotaxonomic characteristics, it is suggested that the isolates represent a novel species in a new genus; the name Formosa algae gen. nov., sp. nov. is proposed. The type strain is KMM 3553(T) (=CIP 107684(T)).

  4. [Influence of intravenous injection of fucoidan from brown seaweed Fucus evanescens by plasma rabbits anticoagulant activity and neutralisation by sulphate protamin of fucoidans antithrombin activity in vitro].

    PubMed

    Lapikova, E S; Drozd, N N; Makarov, V A; Zviagintseva, T N; Shevchenko, N M; Kuznetsova, T A; Besednova, N N

    2012-01-01

    With fucoidan from Fucus evanescens dose increase from 1 to 5 mg/kg plasma coagulation time in test A(see symbol)TB increases. Sulphate protamin in final concentration 0.67-1.35 mkg/ml will neutralise antithrombin activity of fucoidans from brown seaweed Fucus evanescens and Laminaria cichorioides. The gravimetrichesky relation for the investigated samples makes an antidot/anticoagulant 1.

  5. Measuring bioavailable metals using diffusive gradients in thin films (DGT) and transplanted seaweed (Fucus vesiculosus), blue mussels (Mytilus edulis) and sea snails (Littorina saxatilis) suspended from monitoring buoys near a former lead-zinc mine in West Greenland.

    PubMed

    Søndergaard, Jens; Bach, Lis; Gustavson, Kim

    2014-01-15

    Measuring loads of bioavailable metals is important for environmental assessment near mines and other industrial sources. In this study, a setup of monitoring buoys was tested to assess loads of bioavailable metals near a former Pb-Zn mine in West Greenland using transplanted seaweed, mussels and sea snails. In addition, passive DGT samplers were installed. After a 9-day deployment period, concentrations of especially Pb, Zn and Fe in the species were all markedly elevated at the monitoring sites closest to the mine. Lead concentrations in all three species and the DGT-Pb results showed a significant linear correlation. Zinc and Fe concentrations were less correlated indicating that the mechanisms for Zn and Fe accumulation in the three species are more complex. The results show that there is still a significant load of metals from the mine and that such buoys can be an adequate method to assess present loads of bioavailable metals.

  6. Giant viruses infecting algae.

    PubMed

    Van Etten, J L; Meints, R H

    1999-01-01

    Paramecium bursaria chlorella virus (PBCV-1) is the prototype of a family of large, icosahedral, plaque-forming, double-stranded-DNA-containing viruses that replicate in certain unicellular, eukaryotic chlorella-like green algae. DNA sequence analysis of its 330, 742-bp genome leads to the prediction that this phycodnavirus has 376 protein-encoding genes and 10 transfer RNA genes. The predicted gene products of approximately 40% of these genes resemble proteins of known function. The chlorella viruses have other features that distinguish them from most viruses, in addition to their large genome size. These features include the following: (a) The viruses encode multiple DNA methyltransferases and DNA site-specific endonucleases; (b) PBCV-1 encodes at least part, if not the entire machinery to glycosylate its proteins; (c) PBCV-1 has at least two types of introns--a self-splicing intron in a transcription factor-like gene and a splicesomal processed type of intron in its DNA polymerase gene. Unlike the chlorella viruses, large double-stranded-DNA-containing viruses that infect marine, filamentous brown algae have a circular genome and a lysogenic phase in their life cycle.

  7. Miocene Coralline algae

    SciTech Connect

    Bosence, D.W.J.

    1988-01-01

    The coralline algae (Order Corallinales) were sedimentologically and ecologically important during the Miocene, a period when they were particularly abundant. The many poorly described and illustrated species and the lack of quantitative data in coralline thalli make specific determinations particularly difficult, but some species are well known and widespread in the Tethyan area. The sedimentologic importance of the Miocene coralline algae is reflected in the abundance of in-situ coralline buildups, rhodoliths, and coralline debris facies at Malta and Spain; similar sequences are known throughout the Tethyan Miocene. In-situ buildups vary from leafy crustose biostromes to walled reefs with dense coralline crusts and branches. Growth forms are apparently related to hydraulic energy. Rhodoliths vary from leafy, crustose, and open-branched forms in muddy sediments to dense, crustose, and radial-branching forms in coarse grainstones. Rhodolith form and internal structure correlate closely with hydraulic energy. Coralline genera are conservative and, as such, are useful in paleoenvironmental analysis. Of particular interest are the restricted depth ranges of recent coralline genera. More research is needed on the sedimentology, paleoecology, and systematics of the Cenozoic corallines, as they have particular value in paleoenvironmental analysis.

  8. Cellular Auxin Transport in Algae.

    PubMed

    Zhang, Suyun; van Duijn, Bert

    2014-01-27

    The phytohormone auxin is one of the main directors of plant growth and development. In higher plants, auxin is generated in apical plant parts and transported from cell-to-cell in a polar fashion. Auxin is present in all plant phyla, and the existence of polar auxin transport (PAT) is well established in land plants. Algae are a group of relatively simple, autotrophic, photosynthetic organisms that share many features with land plants. In particular, Charophyceae (a taxon of green algae) are closest ancestors of land plants. In the study of auxin function, transport and its evolution, the algae form an interesting research target. Recently, proof for polar auxin transport in Chara species was published and auxin related research in algae gained more attention. In this review we discuss auxin transport in algae with respect to land plants and suggest directions for future studies.

  9. A highly regular fraction of a fucoidan from the brown seaweed Fucus distichus L.

    PubMed

    Bilan, Maria I; Grachev, Alexey A; Ustuzhanina, Nadezhda E; Shashkov, Alexander S; Nifantiev, Nikolay E; Usov, Anatolii I

    2004-02-25

    A fucoidan fraction consisting of L-fucose, sulfate, and acetate in a molar proportion of 1:1.21:0.08 was isolated from the brown seaweed Fucus distichus collected from the Barents Sea. The 13C NMR spectrum of the fraction was typical of regular polysaccharides containing disaccharide repeating units. According to 1D and 2D 1H and 13C NMR spectra, the fucoidan molecules are built up of alternating 3-linked alpha-L-fucopyranose 2,4-disulfate and 4-linked alpha-L-fucopyranose 2-sulfate residues: -->3)-alpha-L-Fucp-(2,4-di-SO3-)-(1-->4)-alpha-L-Fucp-(2SO3-)-(1-->. The regular structure may be only slightly masked by random acetylation and undersulfation of several disaccharide repeating units.

  10. Bioaccumulation of metals by Fucus ceranoides in estuaries of South West England.

    PubMed

    Varma, Ranjit; Turner, Andrew; Brown, Murray T

    2011-11-01

    Fucus ceranoides tolerates abiotic conditions encountered across the full range of estuarine salinities. We examined the bioaccumulation of metals in individuals and metal concentrations in accompanying sediment samples collected at different locations along estuaries of South West England. Intra- and inter-estuarine variations in metal accumulation by F. ceranoides, after correction for particulate contamination using Fe as a proxy, were attributed to variations in the availabilities and concentrations of aqueous metals. Greatest accumulation was observed in estuaries that remain most heavily impacted by historical mining activities and for metals that were mobilised to the greatest extent during these operations (As, Cu, Sn, Zn). Arsenic concentrations displayed a seaward increase in estuaries in which multiple samples were taken, whereas Cd concentrations were always greatest in samples collected from the most landward locations. Ongoing research aims to better understand the mechanisms and kinetics of metal interactions with F. ceranoides and their dependence on salinity.

  11. Fuel From Algae: Scaling and Commercialization of Algae Harvesting Technologies

    SciTech Connect

    2010-01-15

    Broad Funding Opportunity Announcement Project: Led by CEO Ross Youngs, AVS has patented a cost-effective dewatering technology that separates micro-solids (algae) from water. Separating micro-solids from water traditionally requires a centrifuge, which uses significant energy to spin the water mass and force materials of different densities to separate from one another. In a comparative analysis, dewatering 1 ton of algae in a centrifuge costs around $3,400. AVS’s Solid-Liquid Separation (SLS) system is less energy-intensive and less expensive, costing $1.92 to process 1 ton of algae. The SLS technology uses capillary dewatering with filter media to gently facilitate water separation, leaving behind dewatered algae which can then be used as a source for biofuels and bio-products. The biomimicry of the SLS technology emulates the way plants absorb and spread water to their capillaries.

  12. Transgenic algae engineered for higher performance

    DOEpatents

    Unkefer, Pat J; Anderson, Penelope S; Knight, Thomas J

    2014-10-21

    The present disclosure relates to transgenic algae having increased growth characteristics, and methods of increasing growth characteristics of algae. In particular, the disclosure relates to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and a glutamine synthetase.

  13. Biological importance of marine algae.

    PubMed

    El Gamal, Ali A

    2010-01-01

    Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. Algae can be classified into two main groups; first one is the microalgae, which includes blue green algae, dinoflagellates, bacillariophyta (diatoms)… etc., and second one is macroalgae (seaweeds) which includes green, brown and red algae. The microalgae phyla have been recognized to provide chemical and pharmacological novelty and diversity. Moreover, microalgae are considered as the actual producers of some highly bioactive compounds found in marine resources. Red algae are considered as the most important source of many biologically active metabolites in comparison to other algal classes. Seaweeds are used for great number of application by man. The principal use of seaweeds as a source of human food and as a source of gums (phycocollides). Phycocolloides like agar agar, alginic acid and carrageenan are primarily constituents of brown and red algal cell walls and are widely used in industry.

  14. Algae fuel clean electricity generation

    SciTech Connect

    O'Sullivan, D.

    1993-02-08

    The paper describes plans for a 600-kW pilot generating unit, fueled by diesel and Chlorella, a green alga commonly seen growing on the surface of ponds. The plant contains Biocoil units in which Chlorella are grown using the liquid effluents from sewage treatment plants and dissolved carbon dioxide from exhaust gases from the combustion unit. The algae are partially dried and fed into the combustor where diesel fuel is used to maintain ignition. Diesel fuel is also used for start-up and as a backup fuel for seasonal shifts that affect the algae growing conditions. Since the algae use the carbon dioxide emitted during the combustion process, the process will not contribute to global warming.

  15. Logistic analysis of algae cultivation.

    PubMed

    Slegers, P M; Leduc, S; Wijffels, R H; van Straten, G; van Boxtel, A J B

    2015-03-01

    Energy requirements for resource transport of algae cultivation are unknown. This work describes the quantitative analysis of energy requirements for water and CO2 transport. Algae cultivation models were combined with the quantitative logistic decision model 'BeWhere' for the regions Benelux (Northwest Europe), southern France and Sahara. For photobioreactors, the energy consumed for transport of water and CO2 turns out to be a small percentage of the energy contained in the algae biomass (0.1-3.6%). For raceway ponds the share for transport is higher (0.7-38.5%). The energy consumption for transport is the lowest in the Benelux due to good availability of both water and CO2. Analysing transport logistics is still important, despite the low energy consumption for transport. The results demonstrate that resource requirements, resource distribution and availability and transport networks have a profound effect on the location choices for algae cultivation.

  16. Gas Exchange of Algae

    PubMed Central

    Ammann, Elizabeth C. B.; Lynch, Victoria H.

    1965-01-01

    Continuously growing cultures of Chlorella pyrenoidosa Starr 252, operating at constant density and under constant environmental conditions, produced uniform photosynthetic quotient (PQ = CO2/O2) and O2 values during 6 months of observations. The PQ for the entire study was 0.90 ± 0.024. The PQ remained constant over a threefold light-intensity change and a threefold change in O2 production (0.90 ± 0.019). At low light intensities, when the rate of respiration approached the rate of photosynthesis, the PQ became extremely variable. Six lamps of widely different spectral-energy distribution produced no significant change in the PQ (0.90 ± 0.025). Oxygen production was directly related to the number of quanta available, irrespective of spectral-energy distribution. Such dependability in producing uniform PQ and O2 values warrants a consideration of algae to maintain a constant gas environment for submarine or spaceship use. Images Fig. 1 PMID:14339260

  17. Seasonal variations of vegetation patterns and biomass constituents in the rocky eulittoral of Helgoland

    NASA Astrophysics Data System (ADS)

    Munda, I. M.; Markham, J. W.

    1982-06-01

    Seasonal changes in vegetation patterns and biomass of benthic algae were recorded over a 14-month period in the rocky eulittoral of the North Sea island of Helgoland. The area is characterized by the dominance of Fucus serratus throughout most of the eulittoral and this is reflected in higher biomass of F. serratus ranged seasonally from 4.3 kg to 15 kg m-2 in the center of its extensive distribution. Biomass was also recorded monthly, when the plants were present, for Blidingia spp., Enteromorpha spp., Ulva lactuca, Fucus spiralis, F. vesiculosus, Porphyra linearis, P. umbilicalis, Chondrus crispus, Corallina officinalis, Dumontia incrassata, Petalonia fascia, P. zosterifolia and Scytosiphon lomentaria. New generations of several species which reappeared after a destructive winter storm showed a higher protein content than in the previous year. The winter and early spring flora of Helgoland shows several resemblances in species composition to the summer flora of Scandinavia.

  18. Antioxidant and Cytoprotective Activities of Fucus spiralis Seaweed on a Human Cell in Vitro Model

    PubMed Central

    Pinteus, Susete; Silva, Joana; Alves, Celso; Horta, André; Thomas, Olivier P.; Pedrosa, Rui

    2017-01-01

    Antioxidants play an important role as Reactive Oxygen Species (ROS) chelating agents and, therefore, the screening for potent antioxidants from natural sources as potential protective agents is of great relevance. The main aim of this study was to obtain antioxidant-enriched fractions from the common seaweed Fucus spiralis and evaluate their activity and efficiency in protecting human cells (MCF-7 cells) on an oxidative stress condition induced by H2O2. Five fractions, F1–F5, were obtained by reversed-phase vacuum liquid chromatography. F3, F4 and F5 revealed the highest phlorotannin content, also showing the strongest antioxidant effects. The cell death induced by H2O2 was reduced by all fractions following the potency order F4 > F2 > F3 > F5 > F1. Only fraction F4 completely inhibited the H2O2 effect. To understand the possible mechanisms of action of these fractions, the cellular production of H2O2, the mitochondrial membrane potential and the caspase 9 activity were studied. Fractions F3 and F4 presented the highest reduction on H2O2 cell production. All fractions decreased both caspase-9 activity and cell membrane depolarization (except F1). Taken all together, the edible F. spiralis reveal that they provide protection against oxidative stress induced by H2O2 on the human MCF-7 cellular model, probably acting as upstream blockers of apoptosis. PMID:28146076

  19. Antioxidant and Cytoprotective Activities of Fucus spiralis Seaweed on a Human Cell in Vitro Model.

    PubMed

    Pinteus, Susete; Silva, Joana; Alves, Celso; Horta, André; Thomas, Olivier P; Pedrosa, Rui

    2017-01-29

    Antioxidants play an important role as Reactive Oxygen Species (ROS) chelating agents and, therefore, the screening for potent antioxidants from natural sources as potential protective agents is of great relevance. The main aim of this study was to obtain antioxidant-enriched fractions from the common seaweed Fucus spiralis and evaluate their activity and efficiency in protecting human cells (MCF-7 cells) on an oxidative stress condition induced by H₂O₂. Five fractions, F1-F5, were obtained by reversed-phase vacuum liquid chromatography. F3, F4 and F5 revealed the highest phlorotannin content, also showing the strongest antioxidant effects. The cell death induced by H₂O₂ was reduced by all fractions following the potency order F4 > F2 > F3 > F5 > F1. Only fraction F4 completely inhibited the H₂O₂ effect. To understand the possible mechanisms of action of these fractions, the cellular production of H₂O₂, the mitochondrial membrane potential and the caspase 9 activity were studied. Fractions F3 and F4 presented the highest reduction on H₂O₂ cell production. All fractions decreased both caspase-9 activity and cell membrane depolarization (except F1). Taken all together, the edible F. spiralis reveal that they provide protection against oxidative stress induced by H₂O₂ on the human MCF-7 cellular model, probably acting as upstream blockers of apoptosis.

  20. Polysaccharides of the red algae.

    PubMed

    Usov, Anatolii I

    2011-01-01

    Red algae (Rhodophyta) are known as the source of unique sulfated galactans, such as agar, agarose, and carrageenans. The wide practical uses of these polysaccharides are based on their ability to form strong gels in aqueous solutions. Gelling polysaccharides usually have molecules built up of repeating disaccharide units with a regular distribution of sulfate groups, but most of the red algal species contain more complex galactans devoid of gelling ability because of various deviations from the regular structure. Moreover, several red algae may contain sulfated mannans or neutral xylans instead of sulfated galactans as the main structural polysaccharides. This chapter is devoted to a description of the structural diversity of polysaccharides found in the red algae, with special emphasis on the methods of structural analysis of sulfated galactans. In addition to the structural information, some data on the possible use of red algal polysaccharides as biologically active polymers or as taxonomic markers are briefly discussed.

  1. Neuroprotective Effects of Marine Algae

    PubMed Central

    Pangestuti, Ratih; Kim, Se-Kwon

    2011-01-01

    The marine environment is known as a rich source of chemical structures with numerous beneficial health effects. Among marine organisms, marine algae have been identified as an under-exploited plant resource, although they have long been recognized as valuable sources of structurally diverse bioactive compounds. Presently, several lines of studies have provided insight into biological activities and neuroprotective effects of marine algae including antioxidant, anti-neuroinflammatory, cholinesterase inhibitory activity and the inhibition of neuronal death. Hence, marine algae have great potential to be used for neuroprotection as part of pharmaceuticals, nutraceuticals and functional foods. This contribution presents an overview of marine algal neuroprotective effects and their potential application in neuroprotection. PMID:21673890

  2. Microscopic Gardens: A Close Look at Algae.

    ERIC Educational Resources Information Center

    Foote, Mary Ann

    1983-01-01

    Describes classroom activities using algae, including demonstration of eutrophication, examination of mating strains, and activities with Euglena. Includes on algal morphology/physiology, types of algae, and field sources for collecting these organisms. (JN)

  3. Formation of algae growth constitutive relations for improved algae modeling.

    SciTech Connect

    Gharagozloo, Patricia E.; Drewry, Jessica Louise.

    2013-01-01

    This SAND report summarizes research conducted as a part of a two year Laboratory Directed Research and Development (LDRD) project to improve our abilities to model algal cultivation. Algae-based biofuels have generated much excitement due to their potentially large oil yield from relatively small land use and without interfering with the food or water supply. Algae mitigate atmospheric CO2 through metabolism. Efficient production of algal biofuels could reduce dependence on foreign oil by providing a domestic renewable energy source. Important factors controlling algal productivity include temperature, nutrient concentrations, salinity, pH, and the light-to-biomass conversion rate. Computational models allow for inexpensive predictions of algae growth kinetics in these non-ideal conditions for various bioreactor sizes and geometries without the need for multiple expensive measurement setups. However, these models need to be calibrated for each algal strain. In this work, we conduct a parametric study of key marine algae strains and apply the findings to a computational model.

  4. Evolution of the Northern Rockweed, Fucus distichus, in a Regime of Glacial Cycling: Implications for Benthic Algal Phylogenetics

    PubMed Central

    Laughinghouse, Haywood Dail; Müller, Kirsten M.; Adey, Walter H.; Lara, Yannick; Young, Robert; Johnson, Gabriel

    2015-01-01

    Northern hemisphere rockweeds (Fucus) are thought to have evolved in the North Pacific and then spread to the North Atlantic following the opening of the Bering Strait. They have dispersed and widely speciated in the North Atlantic and its tributary seas. Fucus distichus is likely near the ancestral member of this genus, and studies have shown that there are several species/subspecies in this complex (i.e. F. evanescens and F. gardneri). We used phylogenetic and haplotype analyses to test the phylogenetic relationships and biogeography of F. distichus. Our data and subsequent analyses demonstrate that, unlike previous studies that lacked samples from an extensive geographical area of the Arctic and Subarctic, there is a distinct Arctic haplotype that is the source of subspecies in both the North Pacific and North Atlantic. Fucus distichus occupies a low tide zone habitat, and in Arctic/Subarctic regions it is adapted to the severe stress of sea ice coverage and disturbance during many months per year. We hypothesize that the very large geographic area of Arctic and Subarctic rocky shores available to this species during interglacials, supported by large Arctic/Subarctic fringe areas as well as unglaciated refugia during glacial cycles, provided a robust population and gene pool (described by the Thermogeographic Model). This gene pool dilutes that of the more fragmented and area-limited Temperate/Boreal area populations when they are brought together during glacial cycles. We suggest that similar subspecies complexes for a variety of Arctic/Subarctic shore biota should be examined further in this context, rather than arbitrarily being split up into numerous species. PMID:26630571

  5. Evolution of the Northern Rockweed, Fucus distichus, in a Regime of Glacial Cycling: Implications for Benthic Algal Phylogenetics.

    PubMed

    Laughinghouse, Haywood Dail; Müller, Kirsten M; Adey, Walter H; Lara, Yannick; Young, Robert; Johnson, Gabriel

    2015-01-01

    Northern hemisphere rockweeds (Fucus) are thought to have evolved in the North Pacific and then spread to the North Atlantic following the opening of the Bering Strait. They have dispersed and widely speciated in the North Atlantic and its tributary seas. Fucus distichus is likely near the ancestral member of this genus, and studies have shown that there are several species/subspecies in this complex (i.e. F. evanescens and F. gardneri). We used phylogenetic and haplotype analyses to test the phylogenetic relationships and biogeography of F. distichus. Our data and subsequent analyses demonstrate that, unlike previous studies that lacked samples from an extensive geographical area of the Arctic and Subarctic, there is a distinct Arctic haplotype that is the source of subspecies in both the North Pacific and North Atlantic. Fucus distichus occupies a low tide zone habitat, and in Arctic/Subarctic regions it is adapted to the severe stress of sea ice coverage and disturbance during many months per year. We hypothesize that the very large geographic area of Arctic and Subarctic rocky shores available to this species during interglacials, supported by large Arctic/Subarctic fringe areas as well as unglaciated refugia during glacial cycles, provided a robust population and gene pool (described by the Thermogeographic Model). This gene pool dilutes that of the more fragmented and area-limited Temperate/Boreal area populations when they are brought together during glacial cycles. We suggest that similar subspecies complexes for a variety of Arctic/Subarctic shore biota should be examined further in this context, rather than arbitrarily being split up into numerous species.

  6. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species...

  7. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species...

  8. 21 CFR 184.1120 - Brown algae.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species...

  9. 21 CFR 184.1120 - Brown algae.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species...

  10. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species...

  11. 21 CFR 184.1120 - Brown algae.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species...

  12. 21 CFR 184.1120 - Brown algae.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1120 Brown algae. (a) Brown algae are seaweeds of the species Analipus japonicus, Eisenia...

  13. 21 CFR 184.1120 - Brown algae.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species...

  14. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD....1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis furcata, Porphyra...

  15. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Red algae. 184.1121 Section 184.1121 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species...

  16. Algae -- a poor man's HAART?

    PubMed

    Teas, Jane; Hebert, James R; Fitton, J Helen; Zimba, Paul V

    2004-01-01

    Drawing inferences from epidemiologic studies of HIV/AIDS and in vivo and in vitro HIV inhibition by algae, we propose algal consumption as one unifying characteristic of countries with anomalously low rates. HIV/AIDS incidence and prevalence in Eastern Asia ( approximately 1/10000 adults in Japan and Korea), compared to Africa ( approximately 1/10 adults), strongly suggest that differences in IV drug use and sexual behavior are insufficient to explain the 1000-fold variation. Even in Africa, AIDS/HIV rates vary. Chad has consistently reported low rates of HIV/AIDS (2-4/100). Possibly not coincidentally, most people in Japan and Korea eat seaweed daily and the Kanemba, one of the major tribal groups in Chad, eat a blue green alga (Spirulina) daily. Average daily algae consumption in Asia and Africa ranges between 1 and 2 tablespoons (3-13 g). Regular consumption of dietary algae might help prevent HIV infection and suppress viral load among those infected.

  17. Algae. LC Science Tracer Bullet.

    ERIC Educational Resources Information Center

    Niskern, Diana, Comp.

    The plants and plantlike organisms informally grouped together as algae show great diversity of form and size and occur in a wide variety of habitats. These extremely important photosynthesizers are also economically significant. For example, some species contaminate water supplies; others provide food for aquatic animals and for man; still others…

  18. Biological importance of marine algae

    PubMed Central

    El Gamal, Ali A.

    2009-01-01

    Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. Algae can be classified into two main groups; first one is the microalgae, which includes blue green algae, dinoflagellates, bacillariophyta (diatoms)… etc., and second one is macroalgae (seaweeds) which includes green, brown and red algae. The microalgae phyla have been recognized to provide chemical and pharmacological novelty and diversity. Moreover, microalgae are considered as the actual producers of some highly bioactive compounds found in marine resources. Red algae are considered as the most important source of many biologically active metabolites in comparison to other algal classes. Seaweeds are used for great number of application by man. The principal use of seaweeds as a source of human food and as a source of gums (phycocollides). Phycocolloides like agar agar, alginic acid and carrageenan are primarily constituents of brown and red algal cell walls and are widely used in industry. PMID:23960716

  19. The fate of the Arctic seaweed Fucus distichus under climate change: an ecological niche modeling approach.

    PubMed

    Jueterbock, Alexander; Smolina, Irina; Coyer, James A; Hoarau, Galice

    2016-03-01

    Rising temperatures are predicted to melt all perennial ice cover in the Arctic by the end of this century, thus opening up suitable habitat for temperate and subarctic species. Canopy-forming seaweeds provide an ideal system to predict the potential impact of climate-change on rocky-shore ecosystems, given their direct dependence on temperature and their key role in the ecological system. Our primary objective was to predict the climate-change induced range-shift of Fucus distichus, the dominant canopy-forming macroalga in the Arctic and subarctic rocky intertidal. More specifically, we asked: which Arctic/subarctic and cold-temperate shores of the northern hemisphere will display the greatest distributional change of F. distichus and how will this affect niche overlap with seaweeds from temperate regions? We used the program MAXENT to develop correlative ecological niche models with dominant range-limiting factors and 169 occurrence records. Using three climate-change scenarios, we projected habitat suitability of F. distichus - and its niche overlap with three dominant temperate macroalgae - until year 2200. Maximum sea surface temperature was identified as the most important factor in limiting the fundamental niche of F. distichus. Rising temperatures were predicted to have low impact on the species' southern distribution limits, but to shift its northern distribution limits poleward into the high Arctic. In cold-temperate to subarctic regions, new areas of niche overlap were predicted between F. distichus and intertidal macroalgae immigrating from the south. While climate-change threatens intertidal seaweeds in warm-temperate regions, seaweed meadows will likely flourish in the Arctic intertidal. Although this enriches biodiversity and opens up new seaweed-harvesting grounds, it will also trigger unpredictable changes in the structure and functioning of the Arctic intertidal ecosystem.

  20. Fucus as a Model System to Study the Role of Auxin Transport and the Actin Cytoskeleton in Gravity Response

    NASA Technical Reports Server (NTRS)

    Muday, Gloria K.

    2003-01-01

    The overarching goal of this proposal was to examine the mechanisms for the cellular asymmetry in auxin transport proteins. As auxin transport polarity changes in response to reorientation of algal and plant cells relative to the gravity vector, it was critical to ask how auxin transport polarity is established and how this transport polarity may change in response to gravity stimulation. The experiments conducted with this NASA grant fell into two categories. The first area of experimentation was to explore the biochemical interactions between an auxin transport protein and the actin cytoskeleton. These experiments used biochemical techniques, including actin affinity chromatography, to demonstrate that one auxin transport protein interacts with the actin cytoskeleton. The second line of experiments examined whether in the initially symmetrical single celled embryos of Fucus distichus, whether auxin regulates development and whether gravity is a cue to control the morphogenesis of these embryos and whether gravi-morphogenesis is auxin dependent. Results in these two areas are summarized separately below. As a result of this funding, in combination with results from other investigators, we have strong evidence for an important role for the actin cytoskeleton in both establishing and change auxin transport polarity. It is also clear that Fucus distichus embryos are auxin responsive and gravity controls their morphogenesis.

  1. Glycolate Pathway in Algae 1

    PubMed Central

    Hess, J. L.; Tolbert, N. E.

    1967-01-01

    No glycolate oxidase activity could be detected by manometric, isotopic, or spectrophotometric techniques in cell extracts from 5 strains of algae grown in the light with CO2. However, NADH:glyoxylate reductase, phosphoglycolate phosphatase and isocitrate dehydrogenase were detected in the cell extracts. The serine formed by Chlorella or Chlamydomonas after 12 seconds of photosynthetic 14CO2 fixation contained 70 to 80% of its 14C in the carboxyl carbon. This distribution of label in serine was similar to that in phosphoglycerate from the same experiment. Thus, in algae serine is probably formed directly from phosphoglycerate. These results differ from those of higher plants which form uniformly labeled serine from glycolate in short time periods when phosphoglycerate is still carboxyl labeled. In glycolate formed by algae in 5 and 10 seconds of 14CO2 fixation, C2 was at least twice as radioactive as C1. A similar skewed labeling in C2 and C3 of 3-phosphoglycerate and serine suggests a common precursor for glycolate and 3-phosphoglycerate. Glycine formed by the algae, however, from the same experiments was uniformly labeled. Manganese deficient Chlorella incorporated only 2% of the total 14CO2 fixed in 10 minutes into glycolate, while in normal Chlorella 30% of the total 14C was found in glycolate. Manganese deficient Chlorella also accumulated more 14C in glycine and serine. Glycolate excretion by Chlorella was maximal in 10 mm bicarbonate and occurred only in the light, and was not influenced by the addition of glycolate. No time dependent uptake of significant amounts of either glycolate or phosphoglycolate was observed. When small amounts of glycolate-2-14C were fed to Chlorella or Scenedesmus, only 2 to 3% was metabolized after 30 to 60 minutes. The algae were not capable of significant glycolate metabolism as is the higher plant. The failure to detect glycolate oxidase, the low level glycolate-14C metabolism, and the formation of serine from phosphoglycerate

  2. The remote sensing of algae

    NASA Technical Reports Server (NTRS)

    Thorne, J. F.

    1977-01-01

    State agencies need rapid, synoptic and inexpensive methods for lake assessment to comply with the 1972 Amendments to the Federal Water Pollution Control Act. Low altitude aerial photography may be useful in providing information on algal type and quantity. Photography must be calibrated properly to remove sources of error including airlight, surface reflectance and scene-to-scene illumination differences. A 550-nm narrow wavelength band black and white photographic exposure provided a better correlation to algal biomass than either red or infrared photographic exposure. Of all the biomass parameters tested, depth-integrated chlorophyll a concentration correlated best to remote sensing data. Laboratory-measured reflectance of selected algae indicate that different taxonomic classes of algae may be discriminated on the basis of their reflectance spectra.

  3. Halogenated Compounds from Marine Algae

    PubMed Central

    Cabrita, Maria Teresa; Vale, Carlos; Rauter, Amélia Pilar

    2010-01-01

    Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds. PMID:20948909

  4. Parasites in algae mass culture

    PubMed Central

    Carney, Laura T.; Lane, Todd W.

    2014-01-01

    Parasites are now known to be ubiquitous across biological systems and can play an important role in modulating algal populations. However, there is a lack of extensive information on their role in artificial ecosystems such as algal production ponds and photobioreactors. Parasites have been implicated in the demise of algal blooms. Because individual mass culture systems often tend to be unialgal and a select few algal species are in wide scale application, there is an increased potential for parasites to have a devastating effect on commercial scale monoculture. As commercial algal production continues to expand with a widening variety of applications, including biofuel, food and pharmaceuticals, the parasites associated with algae will become of greater interest and potential economic impact. A number of important algal parasites have been identified in algal mass culture systems in the last few years and this number is sure to grow as the number of commercial algae ventures increases. Here, we review the research that has identified and characterized parasites infecting mass cultivated algae, the techniques being proposed and or developed to control them, and the potential impact of parasites on the future of the algal biomass industry. PMID:24936200

  5. Synthetic polyester from algae oil.

    PubMed

    Roesle, Philipp; Stempfle, Florian; Hess, Sandra K; Zimmerer, Julia; Río Bártulos, Carolina; Lepetit, Bernard; Eckert, Angelika; Kroth, Peter G; Mecking, Stefan

    2014-06-23

    Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2-(tBu2 PCH2)2C6H4}Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17- and 1,19-diesters in high purity (>99 %). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester-17/19.17/19 with an advantageously high melting and crystallization temperature.

  6. Halogenated compounds from marine algae.

    PubMed

    Cabrita, Maria Teresa; Vale, Carlos; Rauter, Amélia Pilar

    2010-08-09

    Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds.

  7. Bioaccumulation of nickel by algae

    SciTech Connect

    Wang, H.K.; Wood, J.M.

    1984-02-01

    Six strains of algae and one Euglena sp. were tested for their ability to bioaccumulate nickel. Radioactive /sup 63/Ni was used together with a microplate technique to determine the conditions for nickel removal by axenic cultures of cyanobacteria, green algae, and one euglenoid. The cyanobacteria tested were found to be more sensitive to nickel toxicity than the green algae or the Euglena sp. The concentration factor (CF) for nickel was determined under a variety of conditions and found to be in the range from 0 to 3.0 x 10/sup 3/. The effect of environmental variables on nickel uptake was examined, and a striking pH effect for biaccumulation was observed, with most of the algal strains accumulating nickel optimally at approximately pH 8.0. Competition experiments for binding sites between nickel and other cations as well as with other complexing anions, showed that /sup 63/Ni uptake was affected only by cobalt and by humic acids.

  8. Temporal windows of reproductive opportunity reinforce species barriers in a marine broadcast spawning assemblage

    PubMed Central

    Monteiro, Carla A.; Paulino, Cristina; Jacinto, Rita; Serrão, Ester A.; Pearson, Gareth A.

    2016-01-01

    Prezygotic isolating mechanisms act to limit hybridization and maintain the genetic identity of closely-related species. While synchronous intraspecific spawning is a common phenomenon amongst marine organisms and plays an important role in reproductive success, asynchronous spawning between potentially hybridizing lineages may also be important in maintaining species boundaries. We tested this hypothesis by comparing reproductive synchrony over daily to hourly timescales in a sympatric assemblage of intertidal fucoid algae containing selfing hermaphroditic (Fucus spiralis and Fucus guiryi) and dioecious (Fucus vesiculosus and Fucus serratus) species. Our results confirm that gametes are released on semi-lunar cycles in all species. However, sister species with different mating systems showed asynchronous spawning at finer circadian timescales, thus providing evidence for a partial reproductive barrier between hermaphroditic and dioecious species. Finally, our data also emphasize the ecological, developmental, and/or physiological constraints that operate to restrict reproduction to narrow temporal windows of opportunity in the intertidal zone and more generally the role of ecological factors in marine speciation. PMID:27373816

  9. Stochastic Forecasting of Algae Blooms in Lakes

    SciTech Connect

    Wang, Peng; Tartakovsky, Daniel M.; Tartakovsky, Alexandre M.

    2013-01-15

    We consider the development of harmful algae blooms (HABs) in a lake with uncertain nutrients inflow. Two general frameworks, Fokker-Planck equation and the PDF methods, are developed to quantify the resultant concentration uncertainty of various algae groups, via deriving a deterministic equation of their joint probability density function (PDF). A computational example is examined to study the evolution of cyanobacteria (the blue-green algae) and the impacts of initial concentration and inflow-outflow ratio.

  10. Photobioreactors for mass cultivation of algae.

    PubMed

    Ugwu, C U; Aoyagi, H; Uchiyama, H

    2008-07-01

    Algae have attracted much interest for production of foods, bioactive compounds and also for their usefulness in cleaning the environment. In order to grow and tap the potentials of algae, efficient photobioreactors are required. Although a good number of photobioreactors have been proposed, only a few of them can be practically used for mass production of algae. One of the major factors that limits their practical application in algal mass cultures is mass transfer. Thus, a thorough understanding of mass transfer rates in photobioreactors is necessary for efficient operation of mass algal cultures. In this review article, various photobioreactors that are very promising for mass production of algae are discussed.

  11. Removal of Cd(II), Zn(II) and Pb(II) from aqueous solutions by brown marine macro algae: kinetic modelling.

    PubMed

    Freitas, Olga M M; Martins, Ramiro J E; Delerue-Matos, Cristina M; Boaventura, Rui A R

    2008-05-01

    Specific marine macro algae species abundant at the Portuguese coast (Laminaria hyperborea, Bifurcaria bifurcata, Sargassum muticum and Fucus spiralis) were shown to be effective for removing toxic metals (Cd(II), Zn(II) and Pb(II)) from aqueous solutions. The initial metal concentrations in solution were about 75-100 mg L(-1). The observed biosorption capacities for cadmium, zinc and lead ions were in the ranges of 23.9-39.5, 18.6-32.0 and 32.3-50.4 mg g(-1), respectively. Kinetic studies revealed that the metal uptake rate was rather fast, with 75% of the total amount occurring in the first 10 min for all algal species. Experimental data were well fitted by a pseudo-second order rate equation. The contribution of internal diffusion mechanism was significant only to the initial biosorption stage. Results indicate that all the studied macro algae species can provide an efficient and cost-effective technology for eliminating heavy metals from industrial effluents.

  12. ["Depilation" by micro-algae?].

    PubMed

    Ditrich, H

    1996-01-01

    Itching, reddening and depilation of body hairs was reported by swimmers in the Attersee-lake in Austria. Initially, an environmental crime was suspected. However, further investigations showed that a biological cause was probably responsible for these symptoms. The accrustations found on body hairs turned out in the scanning electron microscope to be dried mucus containing numerous diatoms. The prevailing micro-algae were identified as Cyclotella comensis. Thus, although the phenomenon had a natural, harmless cause, it may happen again given the appropriate environmental conditions.

  13. A tip-high, Ca(2+) -interdependent, reactive oxygen species gradient is associated with polarized growth in Fucus serratus zygotes.

    PubMed

    Coelho, Susana M B; Brownlee, Colin; Bothwell, John H F

    2008-04-01

    We report the existence of a tip-high reactive oxygen species (ROS) gradient in growing Fucus serratus zygotes, using both 5-(and 6-) chloromethyl-2',7'-dichlorodihydrofluorescein and nitroblue tetrazolium staining to report ROS generation. Suppression of the ROS gradient inhibits polarized zygotic growth; conversely, exogenous ROS generation can redirect zygotic polarization following inhibition of endogenous ROS. Confocal imaging of fluo-4 dextran distributions suggests that the ROS gradient is interdependent on the tip-high [Ca(2+)](cyt) gradient which is known to be associated with polarized growth. Our data support a model in which localized production of ROS at the rhizoid tip stimulates formation of a localized tip-high [Ca(2+)](cyt) gradient. Such modulation of intracellular [Ca(2+)](cyt) signals by ROS is a common motif in many plant and algal systems and this study extends this mechanism to embryogenesis.

  14. Cultivation of macroscopic marine algae

    SciTech Connect

    Ryther, J.H.

    1982-11-01

    The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry wt/m/sup 2/.day, greater than the most productive terrestrial plants. This occurs only when the plants are in a suspended culture, with vigorous aeration and an exchange of 25 or more culture volumes of enriched seawater per day, which is not cost-effective. A culture system was designed in which Gracilaria, stocked at a density of 2 kg wet wt/m/sup 2/, grows to double its biomass in one to two weeks; it is then harvested to its starting density, and anaerobically digested to methane. The biomass is soaked for 6 hours in the digester residue, storing enough nutrients for two weeks' growth in unenriched seawater. The methane is combusted for energy and the waste gas is fed to the culture to provide mixing and CO/sub 2/, eliminating the need for aeration and seawater exchange. The green alga Ulva lactuca, unlike Gracilaria, uses bicarbonate as a photosynthesis carbon source, and can grow at high pH, with little or no free CO/sub 2/. It can therefore produce higher yields than Gracilaria in low water exchange conditions. It is also more efficiently converted to methane than is Gracilaria, but cannot tolerate Florida's summer temperatures so cannot be grown year-round. Attempts are being made to locate or produce a high-temperature tolerant strain.

  15. Nutritional And Taste Characteristics Of Algae

    NASA Technical Reports Server (NTRS)

    Karel, M.; Nakhost, Z.

    1992-01-01

    Report describes investigation of chemical composition of blue-green algae Synechococcus 6311, as well as preparation of protein isolate from green alga Scenedesmus obliquus and incorporation into variety of food products evaluated for taste. Part of program to investigate growth of microalgae aboard spacecraft for use as food.

  16. SSMILes: Measuring the Nutrient Tolerance of Algae.

    ERIC Educational Resources Information Center

    Hedgepeth, David J.

    1995-01-01

    Presents an activity integrating mathematics and science intended to introduce students to the use of metric measurement of mass as a way to increase the meaningfulness of observations about variables in life sciences. Involves measuring the nutrient tolerance of algae. Contains a reproducible algae nutrient graph. (Author/MKR)

  17. Effect of Dead Algae on Soil Permeability

    SciTech Connect

    Harvey, R.S.

    2003-02-21

    Since existing basins support heavy growths of unicellular green algae which may be killed by temperature variation or by inadvertent pH changes in waste and then deposited on the basin floor, information on the effects of dead algae on soil permeability was needed. This study was designed to show the effects of successive algal kills on the permeability of laboratory soil columns.

  18. Take a Dip! Culturing Algae Is Easy.

    ERIC Educational Resources Information Center

    James, Daniel E.

    1983-01-01

    Describes laboratory activities using algae as the organisms of choice. These include examination of typical algal cells, demonstration of alternation of generations, sexual reproduction in Oedogonium, demonstration of phototaxis, effect of nitrate concentration on Ankistrodesmus, and study of competition between two algae in the same environment.…

  19. The ice nucleation activity of extremophilic algae.

    PubMed

    Kviderova, Jana; Hajek, Josef; Worland, Roger M

    2013-01-01

    Differences in the level of cold acclimation and cryoprotection estimated as ice nucleation activity in snow algae (Chlamydomonas cf. nivalis and Chloromonas nivalis), lichen symbiotic algae (Trebouxia asymmetrica, Trebouxia erici and Trebouxia glomerata), and a mesophilic strain (Chlamydomonas reinhardti) were evaluated. Ice nucleation activity was measured using the freezing droplet method. Measurements were performed using suspensions of cells of A750 (absorbance at 750 nm) ~ 1, 0.1, 0.01 and 0.001 dilutions for each strain. The algae had lower ice nucleation activity, with the exception of Chloromonas nivalis contaminated by bacteria. The supercooling points of the snow algae were higher than those of lichen photobionts. The supercooling points of both, mesophilic and snow Chlamydomonas strains were similar. The lower freezing temperatures of the lichen algae may reflect either the more extreme and more variable environmental conditions of the original localities or the different cellular structure of the strains examined.

  20. Flocculation of model algae under shear.

    SciTech Connect

    Pierce, Flint; Lechman, Jeremy B.

    2010-11-01

    We present results of molecular dynamics simulations of the flocculation of model algae particles under shear. We study the evolution of the cluster size distribution as well as the steady-state distribution as a function of shear rates and algae interaction parameters. Algal interactions are modeled through a DLVO-type potential, a combination of a HS colloid potential (Everaers) and a yukawa/colloid electrostatic potential. The effect of hydrodynamic interactions on aggregation is explored. Cluster strucuture is determined from the algae-algae radial distribution function as well as the structure factor. DLVO parameters including size, salt concentration, surface potential, initial volume fraction, etc. are varied to model different species of algae under a variety of environmental conditions.

  1. Composting of waste algae: a review.

    PubMed

    Han, Wei; Clarke, William; Pratt, Steven

    2014-07-01

    Although composting has been successfully used at pilot scale to manage waste algae removed from eutrophied water environments and the compost product applied as a fertiliser, clear guidelines are not available for full scale algae composting. The review reports on the application of composting to stabilize waste algae, which to date has mainly been macro-algae, and identifies the peculiarities of algae as a composting feedstock, these being: relatively low carbon to nitrogen (C/N) ratio, which can result in nitrogen loss as NH3 and even N2O; high moisture content and low porosity, which together make aeration challenging; potentially high salinity, which can have adverse consequence for composting; and potentially have high metals and toxin content, which can affect application of the product as a fertiliser. To overcome the challenges that these peculiarities impose co-compost materials can be employed.

  2. Advances in genetic engineering of marine algae.

    PubMed

    Qin, Song; Lin, Hanzhi; Jiang, Peng

    2012-01-01

    Algae are a component of bait sources for animal aquaculture, and they produce abundant valuable compounds for the chemical industry and human health. With today's fast growing demand for algae biofuels and the profitable market for cosmetics and pharmaceuticals made from algal natural products, the genetic engineering of marine algae has been attracting increasing attention as a crucial systemic technology to address the challenge of the biomass feedstock supply for sustainable industrial applications and to modify the metabolic pathway for the more efficient production of high-value products. Nevertheless, to date, only a few marine algae species can be genetically manipulated. In this article, an updated account of the research progress in marine algal genomics is presented along with methods for transformation. In addition, vector construction and gene selection strategies are reviewed. Meanwhile, a review on the progress of bioreactor technologies for marine algae culture is also revisited.

  3. Algae inhibition experiment and load characteristics of the algae solution

    NASA Astrophysics Data System (ADS)

    Xiong, L.; Gao, J. X.; Zhang, Y. X.; Yang, Z. K.; Zhang, D. Q.; He, W.

    2016-08-01

    It is necessary to inhibit microbial growth in an industrial cooling water system. This paper has developed a Monopolar/Bipolar polarity high voltage pulser with load adaptability for an algal experimental study. The load characteristics of the Chlorella pyrenoidosa solution were examined, and it was found that the solution load is resistive. The resistance is related to the plate area, concentration, and temperature of the solution. Furthermore, the pulser's treatment actually inhibits the algae cell growth. This article also explores the influence of various parameters of electric pulses on the algal effect. After the experiment, the optimum pulse parameters were determined to be an electric field intensity of 750 V/cm, a pulse width per second of 120μs, and monopolar polarity.

  4. Green energy from marine algae: biogas production and composition from the anaerobic digestion of Irish seaweed species.

    PubMed

    Vanegas, C H; Bartlett, J

    2013-01-01

    Marine algae have emerged as an alternative feedstock for the production of a number of renewable fuels, including biogas. In addition to energy potential, other characteristics make them attractive as an energy source, including their ability to absorb carbon dioxide (CO2), higher productivity rates than land-based crops and the lack of water use or land competition. For Ireland, biofuels from marine algae can play an important role by reducing imports of fossil fuels as well as providing the necessary energy in rural communities. In this study, five potential seaweed species common in Irish waters, Saccorhiza polyschides, Ulva sp., Laminaria digitata, Fucus serratus and Saccharina latissima, were co-digested individually with bovine slurry. Batch reactors of 120ml and 1000ml were set up and incubated at 35 degrees C to investigate their suitability for production of biogas. Digesters fed with S. latissima produced the maximum methane yield (335 ml g volatile solids(-1) (g(VS)(-1) followed by S. polyschides with 255 ml g(VS)(-1). L. digitata produced 246ml g(VS)(-1) and the lowest yields were from the green seaweed Ulva sp. 191ml g(VS)(-1). The methane and CO2 percentages ranged between 50-72% and 10-45%, respectively. The results demonstrated that the seaweed species investigated are good feedstocks candidates for the production of biogas and methane as a source of energy. Their use on a large-scale process will require further investigation to increase yields and reduce production costs.

  5. Algae biodiesel - a feasibility report

    PubMed Central

    2012-01-01

    Background Algae biofuels have been studied numerous times including the Aquatic Species program in 1978 in the U.S., smaller laboratory research projects and private programs. Results Using Molina Grima 2003 and Department of Energy figures, captial costs and operating costs of the closed systems and open systems were estimated. Cost per gallon of conservative estimates yielded $1,292.05 and $114.94 for closed and open ponds respectively. Contingency scenarios were generated in which cost per gallon of closed system biofuels would reach $17.54 under the generous conditions of 60% yield, 50% reduction in the capital costs and 50% hexane recovery. Price per gallon of open system produced fuel could reach $1.94 under generous assumptions of 30% yield and $0.2/kg CO2. Conclusions Current subsidies could allow biodiesel to be produced economically under the generous conditions specified by the model. PMID:22540986

  6. Profiling of the molecular weight and structural isomer abundance of macroalgae-derived phlorotannins.

    PubMed

    Heffernan, Natalie; Brunton, Nigel P; FitzGerald, Richard J; Smyth, Thomas J

    2015-01-16

    Phlorotannins are a group of complex polymers of phloroglucinol (1,3,5-trihydroxybenzene) unique to macroalgae. These phenolic compounds are integral structural components of the cell wall in brown algae, but also play many secondary ecological roles such as protection from UV radiation and defense against grazing. This study employed Ultra Performance Liquid Chromatography (UPLC) with tandem mass spectrometry to investigate isomeric complexity and observed differences in phlorotannins derived from macroalgae harvested off the Irish coast (Fucus serratus, Fucus vesiculosus, Himanthalia elongata and Cystoseira nodicaulis). Antioxidant activity and total phenolic content assays were used as an index for producing phlorotannin fractions, enriched using molecular weight cut-off dialysis with subsequent flash chromatography to profile phlorotannin isomers in these macroalgae. These fractions were profiled using UPLC-MS with multiple reaction monitoring (MRM) and the level of isomerization for specific molecular weight phlorotannins between 3 and 16 monomers were determined. The majority of the low molecular weight (LMW) phlorotannins were found to have a molecular weight range equivalent to 4-12 monomers of phloroglucinol. The level of isomerization within the individual macroalgal species differed, resulting in substantially different numbers of phlorotannin isomers for particular molecular weights. F. vesiculosus had the highest number of isomers of 61 at one specific molecular mass, corresponding to 12 phloroglucinol units (PGUs). These results highlight the complex nature of these extracts and emphasize the challenges involved in structural elucidation of these compounds.

  7. DGDG and Glycolipids in Plants and Algae.

    PubMed

    Kalisch, Barbara; Dörmann, Peter; Hölzl, Georg

    2016-01-01

    Photosynthetic organelles in plants and algae are characterized by the high abundance of glycolipids, including the galactolipids mono- and digalactosyldiacylglycerol (MGDG, DGDG) and the sulfolipid sulfoquinovosyldiacylglycerol (SQDG). Glycolipids are crucial to maintain an optimal efficiency of photosynthesis. During phosphate limitation, the amounts of DGDG and SQDG increase in the plastids of plants, and DGDG is exported to extraplastidial membranes to replace phospholipids. Algae often use betaine lipids as surrogate for phospholipids. Glucuronosyldiacylglycerol (GlcADG) is a further glycolipid that accumulates under phosphate deprived conditions. In contrast to plants, a number of eukaryotic algae contain very long chain polyunsaturated fatty acids of 20 or more carbon atoms in their glycolipids. The pathways and genes for galactolipid and sulfolipid synthesis are largely conserved between plants, Chlorophyta, Rhodophyta and algae with complex plastids derived from secondary or tertiary endosymbiosis. However, the relative contribution of the endoplasmic reticulum- and plastid-derived lipid pathways for glycolipid synthesis varies between plants and algae. The genes for glycolipid synthesis encode precursor proteins imported into the photosynthetic organelles. While most eukaryotic algae contain the plant-like galactolipid (MGD1, DGD1) and sulfolipid (SQD1, SQD2) synthases, the red alga Cyanidioschyzon harbors a cyanobacterium-type DGDG synthase (DgdA), and the amoeba Paulinella, derived from a more recent endosymbiosis event, contains cyanobacterium-type enzymes for MGDG and DGDG synthesis (MgdA, MgdE, DgdA).

  8. Algae Biofuel in the Nigerian Energy Context

    NASA Astrophysics Data System (ADS)

    Elegbede, Isa; Guerrero, Cinthya

    2016-05-01

    The issue of energy consumption is one of the issues that have significantly become recognized as an important topic of global discourse. Fossil fuels production reportedly experiencing a gradual depletion in the oil-producing nations of the world. Most studies have relatively focused on biofuel development and adoption, however, the awareness of a prospect in the commercial cultivation of algae having potential to create economic boost in Nigeria, inspired this research. This study aims at exploring the potential of the commercialization of a different but commonly found organism, algae, in Nigeria. Here, parameters such as; water quality, light, carbon, average temperature required for the growth of algae, and additional beneficial nutrients found in algae were analysed. A comparative cum qualitative review of analysis was used as the study made use of empirical findings on the work as well as the author's deductions. The research explored the cultivation of algae with the two major seasonal differences (i.e. rainy and dry) in Nigeria as a backdrop. The results indicated that there was no significant difference in the contribution of algae and other sources of biofuels as a necessity for bioenergy in Nigeria. However, for an effective sustainability of this prospect, adequate measures need to be put in place in form of funding, provision of an economically-enabling environment for the cultivation process as well as proper healthcare service in the face of possible health hazard from technological processes. Further studies can seek to expand on the potential of cultivating algae in the Harmattan season.

  9. Method and apparatus for processing algae

    SciTech Connect

    Chew, Geoffrey; Reich, Alton J.; Dykes, Jr., H. Waite; Di Salvo, Roberto

    2012-07-03

    Methods and apparatus for processing algae are described in which a hydrophilic ionic liquid is used to lyse algae cells. The lysate separates into at least two layers including a lipid-containing hydrophobic layer and an ionic liquid-containing hydrophilic layer. A salt or salt solution may be used to remove water from the ionic liquid-containing layer before the ionic liquid is reused. The used salt may also be dried and/or concentrated and reused. The method can operate at relatively low lysis, processing, and recycling temperatures, which minimizes the environmental impact of algae processing while providing reusable biofuels and other useful products.

  10. Errors When Extracting Oil from Algae

    NASA Astrophysics Data System (ADS)

    Murphy, E.; Treat, R.; Ichiuji, T.

    2014-12-01

    Oil is in popular demand, but the worldwide amount of oil is decreasing and prices for it are steadily increasing. Leading scientists have been working to find a solution of attaining oil in an economically and environmentally friendly way. Researchers at the U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) have determined that "a small mixture of algae and water can be turned into crude oil in less than an hour" (Sheehan, Duhahay, Benemann, Poessler). There are various ways of growing the algae, such as closed loop and open loop methods, as well as processes of extracting oil, such as hydrothermal liquefaction and the hexane-solvent method. Our objective was to grow the algae (C. reinhardtii) and extract oil from it using NaOH and HCl, because we had easy access to those specific chemicals. After two trials of attempted algae growth, we discovered that a bacteria was killing off the algae. This led us to further contemplation on how this dead algae and bacteria are affecting our environment, and the organisms within it. Eutrophication occurs when excess nutrients stimulate rapid growth of algae in an aquatic environment. This can clog waterways and create algal blooms in blue-green algae, as well as neurotoxic red tide phytoplankton. These microscopic algae die upon consumption of the nutrients in water and are degraded by bacteria. The bacteria respires and creates an acidic environment with the spontaneous conversion of carbon dioxide to carbonic acid in water. This process of degradation is exactly what occurred in our 250 mL flask. When the phytoplankton attacked our algae, it created a hypoxic environment, which eliminated any remaining amounts of oxygen, carbon dioxide, and nutrients in the water, resulting in a miniature dead zone. These dead zones can occur almost anywhere where there are algae and bacteria, such as the ocean, and make it extremely difficult for any organism to survive. This experiment helped us realize the

  11. 21 CFR 73.275 - Dried algae meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Dried algae meal. 73.275 Section 73.275 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.275 Dried algae meal. (a) Identity. The color additive dried algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture...

  12. 21 CFR 73.275 - Dried algae meal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Dried algae meal. 73.275 Section 73.275 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.275 Dried algae meal. (a) Identity. The color additive dried algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture...

  13. 2011 Biomass Program Platform Peer Review: Algae

    SciTech Connect

    Yang, Joyce

    2012-02-01

    This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the 2011 U.S. Department of Energy Biomass Program’s Algae Platform Review meeting.

  14. Collection, Isolation and Culture of Marine Algae.

    ERIC Educational Resources Information Center

    James, Daniel E.

    1984-01-01

    Methods of collecting, isolating, and culturing microscopic and macroscopic marine algae are described. Three different culture media list of chemicals needed and procedures for preparing Erdschreiber's and Provasoli's E. S. media. (BC)

  15. Pyogenic Flexor Tenosynovitis Caused by Shewanella algae.

    PubMed

    Fluke, Erin C; Carayannopoulos, Nikoletta L; Lindsey, Ronald W

    2016-07-01

    Pyogenic flexor tenosynovitis is an orthopedic emergency most commonly caused by Staphylococcus aureus and streptococci and occasionally, when associated with water exposure, Mycobacterium marinum. Shewanella algae, a gram-negative bacillus found in warm saltwater environments, has infrequently been reported to cause serious soft tissue infections and necrosis. In this case, S. algae caused complicated flexor tenosynovitis requiring open surgical irrigation and debridement. Flexor tenosynovitis caused by S. algae rapidly presented with all 4 Kanavel cardinal signs as well as subcutaneous purulence, ischemia, and necrosis, thus meeting the requirements for Pang et al group III classification of worst prognosis. Because of its rarity and virulence, S. algae should always be considered in cases of flexor tenosynovitis associated with traumatic water exposure to treat and minimize morbidity appropriately.

  16. Stochastic Forecasting of Algae Blooms in Lakes

    SciTech Connect

    Wang, Peng; Tartakovsky, Daniel M.; Tartakovsky, Alexandre M.

    2013-01-03

    We consider a general framework to predict the development of harmful algal blooms (HABs) in a lake driven by uncertain parameters. To quantify the concentration uncertainty of those algae groups via their joint probabilistic density function (PDF), we explore an approach based on the Fokker-Planck equation. Our result is presented in an example where abundant nutrients contribute to the proliferation of cyanobacteria and other minor algae groups.

  17. Effect of Interactions Among Algae on Nitrogen Fixation by Blue-Green Algae (Cyanobacteria) in Flooded Soils

    PubMed Central

    Wilson, John T.; Greene, Sarah; Alexander, Martin

    1979-01-01

    Nitrogen fixation (C2H2 reduction) by algae in flooded soil was limited by interactions within the algal community. Nitrogen fixation by either indigenous algae or Tolypothrix tenuis was reduced severalfold by a dense suspension of the green alga Nephrocytium sp. Similarly, interactions between the nitrogen-fixing alga (cyanobacterium) Aulosira 68 and natural densities of indigenous algae limited nitrogen-fixing activity in one of two soils examined. This was demonstrated by developing a variant of Aulosira 68 that was resistant to the herbicide simetryne at concentrations that prevented development of indigenous algae. More nitrogen was fixed by the resistant variant in flooded soil containing herbicide than was fixed in herbicide-free soil by either the indigenous algae or indigenous algae plus the parent strain of Aulosira. Interference from indigenous algae may hamper the development of nitrogen-fixing algae introduced into rice fields in attempts to increase biological nitrogen fixation. PMID:16345463

  18. Biogas production experimental research using algae.

    PubMed

    Baltrėnas, Pranas; Misevičius, Antonas

    2015-01-01

    The current study is on the the use of macro-algae as feedstock for biogas production. Three types of macro-algae, Cladophora glomerata (CG), Chara fragilis (CF), and Spirogyra neglecta (SN), were chosen for this research. The experimental studies on biogas production were carried out with these algae in a batch bioreactor. In the bioreactor was maintained 35 ± 1°C temperature. The results showed that the most appropriate macro-algae for biogas production are Spirogyra neglecta (SN) and Cladophora glomerata (CG). The average amount of biogas obtained from the processing of SN - 0.23 m(3)/m(3)d, CG - 0.20 m(3)/m(3)d, and CF - 0.12 m(3)/m(3)d. Considering the concentration of methane obtained during the processing of SN and CG, which after eight days and until the end of the experiment exceeded 60%, it can be claimed that biogas produced using these algae is valuable. When processing CF, the concentration of methane reached the level of 50% only by the final day of the experiment, which indicates that this alga is less suitable for biogas production.

  19. Antioxidant Activity of Hawaiian Marine Algae

    PubMed Central

    Kelman, Dovi; Posner, Ellen Kromkowski; McDermid, Karla J.; Tabandera, Nicole K.; Wright, Patrick R.; Wright, Anthony D.

    2012-01-01

    Marine algae are known to contain a wide variety of bioactive compounds, many of which have commercial applications in pharmaceutical, medical, cosmetic, nutraceutical, food and agricultural industries. Natural antioxidants, found in many algae, are important bioactive compounds that play an important role against various diseases and ageing processes through protection of cells from oxidative damage. In this respect, relatively little is known about the bioactivity of Hawaiian algae that could be a potential natural source of such antioxidants. The total antioxidant activity of organic extracts of 37 algal samples, comprising of 30 species of Hawaiian algae from 27 different genera was determined. The activity was determined by employing the FRAP (Ferric Reducing Antioxidant Power) assays. Of the algae tested, the extract of Turbinaria ornata was found to be the most active. Bioassay-guided fractionation of this extract led to the isolation of a variety of different carotenoids as the active principles. The major bioactive antioxidant compound was identified as the carotenoid fucoxanthin. These results show, for the first time, that numerous Hawaiian algae exhibit significant antioxidant activity, a property that could lead to their application in one of many useful healthcare or related products as well as in chemoprevention of a variety of diseases including cancer. PMID:22412808

  20. Photopolarization of Fucus zygotes is determined by time sensitive vectorial addition of environmental cues during axis amplification.

    PubMed

    Bogaert, Kenny A; Beeckman, Tom; De Clerck, Olivier

    2015-01-01

    Fucoid zygotes have been extensively used to study cell polarization and asymmetrical cell division. Fertilized eggs are responsive to different environmental cues (e.g., light, gravity) for a long period before the polarity is fixed and the cells germinate accordingly. First, it is commonly believed that the direction and sense of the polarization vector are established simultaneously as indicated by the formation of an F-actin patch. Secondly, upon reorientation of the zygote, a new polar gradient is formed and it is assumed that the position of the future rhizoid pole is only influenced by the latter. Here we tested these two hypotheses investigating photopolarization in Fucus zygotes by reorienting zygotes 90° relative to a unilateral light source at different time points during the first cell cycle. We conclude that fixation of direction and sense of the polarization vector is indeed established simultaneously. However, the experiments yielded a distribution of polarization axes that cannot be explained if only the last environmental cue is supposed to determine the polarization axis. We conclude that our observations, together with published findings, can only be explained by assuming imprinting of the different polarization vectors and their integration as a vectorial sum at the moment of axis fixation. This way cells will average different serially perceived cues resulting in a polarization vector representative of the dynamic intertidal environment, instead of betting exclusively on the perceived vector at the moment of axis fixation.

  1. Photopolarization of Fucus zygotes is determined by time sensitive vectorial addition of environmental cues during axis amplification

    PubMed Central

    Bogaert, Kenny A.; Beeckman, Tom; De Clerck, Olivier

    2015-01-01

    Fucoid zygotes have been extensively used to study cell polarization and asymmetrical cell division. Fertilized eggs are responsive to different environmental cues (e.g., light, gravity) for a long period before the polarity is fixed and the cells germinate accordingly. First, it is commonly believed that the direction and sense of the polarization vector are established simultaneously as indicated by the formation of an F-actin patch. Secondly, upon reorientation of the zygote, a new polar gradient is formed and it is assumed that the position of the future rhizoid pole is only influenced by the latter. Here we tested these two hypotheses investigating photopolarization in Fucus zygotes by reorienting zygotes 90° relative to a unilateral light source at different time points during the first cell cycle. We conclude that fixation of direction and sense of the polarization vector is indeed established simultaneously. However, the experiments yielded a distribution of polarization axes that cannot be explained if only the last environmental cue is supposed to determine the polarization axis. We conclude that our observations, together with published findings, can only be explained by assuming imprinting of the different polarization vectors and their integration as a vectorial sum at the moment of axis fixation. This way cells will average different serially perceived cues resulting in a polarization vector representative of the dynamic intertidal environment, instead of betting exclusively on the perceived vector at the moment of axis fixation. PMID:25691888

  2. Variation in thermal stress response in two populations of the brown seaweed, Fucus distichus, from the Arctic and subarctic intertidal

    PubMed Central

    Smolina, Irina; Kollias, Spyros; Jueterbock, Alexander; Coyer, James A.; Hoarau, Galice

    2016-01-01

    It is unclear whether intertidal organisms are ‘preadapted’ to cope with the increase of temperature and temperature variability or if they are currently at their thermal tolerance limits. To address the dichotomy, we focused on an important ecosystem engineer of the Arctic intertidal rocky shores, the seaweed Fucus distichus and investigated thermal stress responses of two populations from different temperature regimes (Svalbard and Kirkenes, Norway). Thermal stress responses at 20°C, 24°C and 28°C were assessed by measuring photosynthetic performance and expression of heat shock protein (HSP) genes (shsp, hsp90 and hsp70). We detected population-specific responses between the two populations of F. distichus, as the Svalbard population revealed a smaller decrease in photosynthesis performance but a greater activation of molecular defence mechanisms (indicated by a wider repertoire of HSP genes and their stronger upregulation) compared with the Kirkenes population. Although the temperatures used in our study exceed temperatures encountered by F. distichus at the study sites, we believe response to these temperatures may serve as a proxy for the species’ potential to respond to climate-related stresses. PMID:26909170

  3. Anti-inflammatory potential of monogalactosyl diacylglycerols and a monoacylglycerol from the edible brown seaweed Fucus spiralis Linnaeus.

    PubMed

    Lopes, Graciliana; Daletos, Georgios; Proksch, Peter; Andrade, Paula B; Valentão, Patrícia

    2014-03-11

    A monoacylglycerol (1) and a 1:1 mixture of two monogalactosyl diacylglycerols (MGDGs) (2 and 3) were isolated from the brown seaweed Fucus spiralis Linnaeus. The structures were elucidated by spectroscopic means (NMR and MS) and by comparison with the literature. Compound 1 was composed of a glycerol moiety linked to oleic acid (C18:1 Ω9). Compounds 2 and 3 contained a glycerol moiety linked to a galactose unit and eicosapentaenoic acid (C20:5 Ω3) combined with octadecatetraenoic acid (C18:4 Ω3) or linolenic acid (C18:3 Ω3), respectively. The isolated compounds were tested for their cytotoxic and anti-inflammatory activity in RAW 264.7 macrophage cells. All of them inhibited NO production at non-cytotoxic concentrations. The fraction consisting of compounds 2 and 3, in a ratio of 1:1, was slightly more effective than compound 1 (IC₅₀ of 60.06 and 65.70 µg/mL, respectively). To our knowledge, this is the first report of these compounds from F. spiralis and on their anti-inflammatory capacity.

  4. Fucus spiralis as monitoring tool of metal contamination in the northwest coast of Portugal under the European Water Framework Directives.

    PubMed

    Reis, Pedro A; Cassiano, Júlia; Veiga, Puri; Rubal, Marcos; Sousa-Pinto, Isabel

    2014-09-01

    Metals (Cd, Cr, Cu, Fe, Mn and Zn) in coastal seawaters and soft tissues of macroalga Fucus spiralis from the northwest coast of Portugal were determined to assess spatial variations of metal bioavailabilities and bioaccumulation factors to compare different ecological quality classifications. Both coastal seawaters and soft tissues of F. spiralis showed significant spatial variations in their metal concentrations along the coast. The macroalgae F. spiralis accumulated more efficiently Cd, Mn and Zn and showed low bioaccumulation factors to Cr, Cu and Fe. Regarding the metal guidelines of the Norwegian Pollution Control Authority, the entire northwest (NW) coast of Portugal in April 2013 should be classified as 'class I--unpolluted' for all metals, except in Ave for Cu ('class II--moderately polluted') and Cavado for Cd and Cu ('class II-moderately polluted'), revealing the low metal bioavailabilities of these seawaters. As there were always significant positive correlations between all metals in seawaters and F. spiralis, this macroalga species was considered a suitable monitoring tool of metal contamination in the NW coast of Portugal and a useful aquatic organism to be included in the European Environmental Specimen Banks in order to establish a real-time environmental monitoring network under the European Water Framework Directives.

  5. Variation in thermal stress response in two populations of the brown seaweed, Fucus distichus, from the Arctic and subarctic intertidal.

    PubMed

    Smolina, Irina; Kollias, Spyros; Jueterbock, Alexander; Coyer, James A; Hoarau, Galice

    2016-01-01

    It is unclear whether intertidal organisms are 'preadapted' to cope with the increase of temperature and temperature variability or if they are currently at their thermal tolerance limits. To address the dichotomy, we focused on an important ecosystem engineer of the Arctic intertidal rocky shores, the seaweed Fucus distichus and investigated thermal stress responses of two populations from different temperature regimes (Svalbard and Kirkenes, Norway). Thermal stress responses at 20°C, 24°C and 28°C were assessed by measuring photosynthetic performance and expression of heat shock protein (HSP) genes (shsp, hsp90 and hsp70). We detected population-specific responses between the two populations of F. distichus, as the Svalbard population revealed a smaller decrease in photosynthesis performance but a greater activation of molecular defence mechanisms (indicated by a wider repertoire of HSP genes and their stronger upregulation) compared with the Kirkenes population. Although the temperatures used in our study exceed temperatures encountered by F. distichus at the study sites, we believe response to these temperatures may serve as a proxy for the species' potential to respond to climate-related stresses.

  6. Hyperspectral imaging of snow algae and green algae from aeroterrestrial habitats.

    PubMed

    Holzinger, Andreas; Allen, Michael C; Deheyn, Dimitri D

    2016-09-01

    Snow algae and green algae living in aeroterrestrial habitats are ideal objects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charophyte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorption spectra of these microalgae in the waveband of 400-900nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance between 400-550nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this high absorbance was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did hardly change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400-500nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation.

  7. Hyperspectral imaging of snow algae and green algae from aeroterrestrial habitats

    PubMed Central

    Holzinger, Andreas; Allen, Michael C.; Deheyn, Dimitri D.

    2016-01-01

    Snow algae and green algae living in aeroterrestrial habitats are ideal obbjects to study adaptation to high light irradiation. Here, we used a detailed description of the spectral properties as a proxy for photo-acclimation/protection in snow algae (Chlamydomonas nivalis, Chlainomonas sp. and Chloromonas sp.) and charopyhte green algae (Zygnema sp., Zygogonium ericetorum and Klebsormidium crenulatum). The hyperspectral microscopic mapping and imaging technique allowed us to acquire total absorbance spectra of these microalgae in the waveband of 400-900 nm. Particularly in Chlamydomonas nivalis and Chlainomonas sp., a high absorbance in the wave band of 400-550 nm was observed, due to naturally occurring secondary carotenoids; in Chloromonas sp. and in the charopyhte algae this was missing, the latter being close relatives to land plants. To investigate if cellular water loss has an influence on the spectral properties, the cells were plasmolysed in sorbitol or desiccated at ambient air. While in snow algae, these treatments did not change the spectral properties, in the charopyhte algae the condensation of the cytoplasm and plastids increased the absorbance in the lower waveband of 400 – 500 nm. These changes might be ecologically relevant and photoprotective, as aeroterrestrial algae are naturally exposed to occasional water limitation, leading to desiccation, which are conditions usually occurring together with higher irradiation. PMID:27442511

  8. PPR proteins of green algae

    PubMed Central

    Tourasse, Nicolas J; Choquet, Yves; Vallon, Olivier

    2013-01-01

    Using the repeat finding algorithm FT-Rep, we have identified 154 pentatricopeptide repeat (PPR) proteins in nine fully sequenced genomes from green algae (with a total of 1201 repeats) and grouped them in 47 orthologous groups. All data are available in a database, PPRdb, accessible online at http://giavap-genomes.ibpc.fr/ppr. Based on phylogenetic trees generated from the repeats, we propose evolutionary scenarios for PPR proteins. Two PPRs are clearly conserved in the entire green lineage: MRL1 is a stabilization factor for the rbcL mRNA, while HCF152 binds in plants to the psbH-petB intergenic region. MCA1 (the stabilization factor for petA) and PPR7 (a short PPR also acting on chloroplast mRNAs) are conserved across the entire Chlorophyta. The other PPRs are clade-specific, with evidence for gene losses, duplications, and horizontal transfer. In some PPR proteins, an additional domain found at the C terminus provides clues as to possible functions. PPR19 and PPR26 possess a methyltransferase_4 domain suggesting involvement in RNA guanosine methylation. PPR18 contains a C-terminal CBS domain, similar to the CBSPPR1 protein found in nucleoids. PPR16, PPR29, PPR37, and PPR38 harbor a SmR (MutS-related) domain similar to that found in land plants pTAC2, GUN1, and SVR7. The PPR-cyclins PPR3, PPR4, and PPR6, in addition, contain a cyclin domain C-terminal to their SmR domain. PPR31 is an unusual PPR-cyclin containing at its N terminus an OctotricoPeptide Repeat (OPR) and a RAP domain. We consider the possibility that PPR proteins with a SmR domain can introduce single-stranded nicks in the plastid chromosome. PMID:24021981

  9. Estimation of alga growth stage and lipid content growth rate

    NASA Technical Reports Server (NTRS)

    Embaye, Tsegereda N. (Inventor); Trent, Jonathan D. (Inventor)

    2012-01-01

    Method and system for estimating a growth stage of an alga in an ambient fluid. Measured light beam absorption or reflection values through or from the alga and through an ambient fluid, in each of two or more wavelength sub-ranges, are compared with reference light beam absorption values for corresponding wavelength sub-ranges for in each alga growth stage to determine (1) which alga growth stage, if any, is more likely and (2) whether estimated lipid content of the alga is increasing or has peaked. Alga growth is preferably terminated when lipid content has approximately reached a maximum value.

  10. Controlled regular locomotion of algae cell microrobots.

    PubMed

    Xie, Shuangxi; Jiao, Niandong; Tung, Steve; Liu, Lianqing

    2016-06-01

    Algae cells can be considered as microrobots from the perspective of engineering. These organisms not only have a strong reproductive ability but can also sense the environment, harvest energy from the surroundings, and swim very efficiently, accommodating all these functions in a body of size on the order of dozens of micrometers. An interesting topic with respect to random swimming motions of algae cells in a liquid is how to precisely control them as microrobots such that they swim according to manually set routes. This study developed an ingenious method to steer swimming cells based on the phototaxis. The method used a varying light signal to direct the motion of the cells. The swimming trajectory, speed, and force of algae cells were analyzed in detail. Then the algae cell could be controlled to swim back and forth, and traverse a crossroad as a microrobot obeying specific traffic rules. Furthermore, their motions along arbitrarily set trajectories such as zigzag, and triangle were realized successfully under optical control. Robotize algae cells can be used to precisely transport and deliver cargo such as drug particles in microfluidic chip for biomedical treatment and pharmacodynamic analysis. The study findings are expected to bring significant breakthrough in biological drives and new biomedical applications.

  11. [Functional components in fish and algae oils].

    PubMed

    Conchillo, A; Valencia, I; Puente, A; Ansorena, D; Astiasarán, I

    2006-01-01

    An important area of the development of new functional foods is facussed on finding or applying food components which favour achieving a healthier lipid profile in the organism. The objective of this work was to carry out the characterisation of the lipid fraction of two oils, fish oil and algae oil, to evaluate their potential use as functional ingredients, in relation to the high molecular weight fatty acid content and the presence of sterols and other components of the unsaponificable fraction. Both oils showed a lipid fraction rich in high molecular weight polyunsaturated omega-3 fatty acids, containing a 33.75% in the fish oil and a 43.97% in the algae oil. Eicosapentaenoic acid was the major fatty acid in fish oil, whereas docosahexaenoic was the most abundant fatty acid in algae oil. The omega-6/omega-3 ratio was lower than 0.4 in both oils. In the unsaponificable fraction, algae oil had a Mold lower cholesterol content and a higher proportion of squalene than fish oil. The phytosterol content was significantly higher in the algae oil.

  12. Oil from algae; salvation from peak oil?

    PubMed

    Rhodes, Christopher J

    2009-01-01

    A review is presented of the use of algae principally to produce biodiesel fuel, as a replacement for conventional fuel derived from petroleum. The imperative for such a strategy is that cheap supplies of crude oil will begin to wane within a decade and land-based crops cannot provide more than a small amount of the fuel the world currently uses, even if food production were allowed to be severely compromised. For comparison, if one tonne of biodiesel might be produced say, from rape-seed per hectare, that same area of land might ideally yield 100 tonnes of biodiesel grown from algae. Placed into perspective, the entire world annual petroleum demand which is now provided for by 31 billion barrels of crude oil might instead be met from algae grown on an area equivalent to 4% of that of the United States. As an additional benefit, in contrast to growing crops it is not necessary to use arable land, since pond-systems might be placed anywhere, even in deserts, and since algae grow well on saline water or wastewaters, no additional burden is imposed on freshwater-a significant advantage, as water shortages threaten. Algae offer the further promise that they might provide future food supplies, beyond what can be offered by land-based agriculture to a rising global population.

  13. Biological toxicity of lanthanide elements on algae.

    PubMed

    Tai, Peidong; Zhao, Qing; Su, Dan; Li, Peijun; Stagnitti, Frank

    2010-08-01

    The biological toxicity of lanthanides on marine monocellular algae was investigated. The specific objective of this research was to establish the relationship between the abundance in the seawater of lanthanides and their biological toxicities on marine monocellular algae. The results showed that all single lanthanides had similar toxic effects on Skeletonema costatum. High concentrations of lanthanides (29.04+/-0.61 micromol L(-1)) resulted in 50% reduction in growth of algae compared to the controls (0 micromol L(-1)) after 96 h (96 h-EC50). The biological toxicity of 13 lanthanides on marine monocellular algae was unrelated with the abundance of different lanthanide elements in nature, and the "Harkins rule" was not appropriate for the lanthanides. A mixed solution that contained equivalent concentrations of each lanthanide element had the same inhibition effect on algae cells as each individual lanthanide element at the same total concentration. This phenomenon is unique compared to the groups of other elements in the periodic table. Hence, we speculate that the monocellular organisms might not be able to sufficiently differentiate between the almost chemically identical lanthanide elements.

  14. Studies on marine algae for haemagglutinic activity.

    PubMed

    Alam, M T; Usmanghani, K

    1994-07-01

    Lectins (agglutinins) are important in medical and immunological applications. Phytohaemagglutinins have been found useful in blood banking. Keeping in view of these facts, the marine algae found at Karachi coastal region have been screened for agglutinic activity by using human erythrocytes of A, B, AB and 0 group. Altogether 53 algal samples were collected and subjected to extraction, fractionation serial dilution and titre determinations. The total marine algae screened for haemagglutinic activity were 44 out of these 14, 13 and 17 belonged to Chlorophyta, Phaeophyta, and Rhodophyta respectively. Among these three groups the Rhodophyta showed the highest number of lytic activity. The green marine alga Valoniopsis pachynema showed a titre value between 2(2) and 2(3), which is statistically significant. In case of brown marine algae Colpomenia sinuosa was found to be active (titre 2(3)), while Dictyota dichotoma, D. indica and Iyengaria stellata, furnished week titre value as 2(2). The red marine algae screened were 17, out of these 4 spp. showed significant activity (titre 2(3)), and these are Gelidium usmanghani, Gracilaria foliifera Hypnea pannosa and Hynea valentiae. While Scinaia fascicularis, Scinaia indica and Champia parvula were found to be weak in their onset on human erythrocytes. The results obtained were quite in agreement with those reported in the literature.

  15. Characterization of the egg vesicular components in the seaweed, Fucus serratus L. (Fucales, Phaeophyta), using enzyme histochemistry and vital staining: the search for a lysosome-like body.

    PubMed

    Holland, R D; Pitt, D; Moore, M N; Brownlee, C

    1997-03-01

    Fucus serratus eggs were examined for evidence of the existence of a lysosome-like body using enzyme histochemical and vital staining techniques. Simultaneous coupling azo-dye techniques for lysosomal acid phosphatase proved inappropriate owing to endogenous phenolic binding artefacts. The large number of alginate polysaccharide and polyphenolic egg vesicles interfered with vital staining techniques for lysosomes. Lysosomal esterase activity was detected in the abundant egg lipid bodies. The role of the egg lipid body as an equivalent lysosome-like body of higher plants, the spherosome, is discussed in relation to egg fertilization and early zygote development.

  16. Turning Algae into Energy in New Mexico

    ScienceCinema

    Sayre, Richard; Olivares, Jose; Lammers, Peter

    2016-07-12

    Los Alamos National Laboratory, as part of the New Mexico Consortium - comprised of New Mexico's major research universities, the Lab, and key industry partners - is conducting research into using algae as a feed stock for a renewable source of fuels, and other products. There are hundreds of thousands of different algae species on Earth. They account for approximately half of the net photosynthesis on the planet, yet they have not been used in any kind of a large scale by humanity, with just a few exceptions. And yet, the biomass is easy to transform into useful products, including fuels, and they contain many other natural products that have high value. In this video Los Alamos and New Mexico State University scientists outline the opportunities and challenges of using science to turn algae into energy.

  17. Turning Algae into Energy in New Mexico

    SciTech Connect

    Sayre, Richard; Olivares, Jose; Lammers, Peter

    2013-07-29

    Los Alamos National Laboratory, as part of the New Mexico Consortium - comprised of New Mexico's major research universities, the Lab, and key industry partners - is conducting research into using algae as a feed stock for a renewable source of fuels, and other products. There are hundreds of thousands of different algae species on Earth. They account for approximately half of the net photosynthesis on the planet, yet they have not been used in any kind of a large scale by humanity, with just a few exceptions. And yet, the biomass is easy to transform into useful products, including fuels, and they contain many other natural products that have high value. In this video Los Alamos and New Mexico State University scientists outline the opportunities and challenges of using science to turn algae into energy.

  18. Lipids and lipid metabolism in eukaryotic algae.

    PubMed

    Guschina, Irina A; Harwood, John L

    2006-03-01

    Eukaryotic algae are a very diverse group of organisms which inhabit a huge range of ecosystems from the Antarctic to deserts. They account for over half the primary productivity at the base of the food chain. In recent years studies on the lipid biochemistry of algae has shifted from experiments with a few model organisms to encompass a much larger number of, often unusual, algae. This has led to the discovery of new compounds, including major membrane components, as well as the elucidation of lipid signalling pathways. A major drive in recent research have been attempts to discover genes that code for expression of the various proteins involved in the production of very long-chain polyunsaturated fatty acids such as arachidonic, eicosapentaenoic and docosahexaenoic acids. Such work is described here together with information about how environmental factors, such as light, temperature or minerals, can change algal lipid metabolism and how adaptation may take place.

  19. Algae control problems and practices workshop

    SciTech Connect

    Pryfogle, P.A.; Ghio, G.

    1996-09-01

    Western water resources are continuously facing increased demand from industry and the public. Consequently, many of these resources are required to perform multiple tasks as they cycle through the ecosystem. Many plants and animals depend upon these resources for growth. Algae are one group of plants associated with nutrient and energy cycles in many aquatic ecosystems. Although most freshwater algae are microscopic in size, they are capable of dominating and proliferating to the extent that the value of the water resource for both industrial and domestic needs is compromised. There is a great diversity of aquatic environments and systems in which algae may be found, and there are many varieties of treatment and control techniques available to reduce the impacts of excessive growth. This workshop was organized to exchange information about these control problems and practices.

  20. Study of metal bioaccumulation by nuclear microprobe analysis of algae fossils and living algae cells

    NASA Astrophysics Data System (ADS)

    Guo, P.; Wang, J.; Li, X.; Zhu, J.; Reinert, T.; Heitmann, J.; Spemann, D.; Vogt, J.; Flagmeyer, R.-H.; Butz, T.

    2000-03-01

    Microscopic ion-beam analysis of palaeo-algae fossils and living green algae cells have been performed to study the metal bioaccumulation processes. The algae fossils, both single cellular and multicellular, are from the late Neoproterozonic (570 million years ago) ocean and perfectly preserved within a phosphorite formation. The biosorption of the rare earth element ions Nd 3+ by the green algae species euglena gracilis was investigated with a comparison between the normal cells and immobilized ones. The new Leipzig Nanoprobe, LIPSION, was used to produce a proton beam with 2 μm size and 0.5 nA beam current for this study. PIXE and RBS techniques were used for analysis and imaging. The observation of small metal rich spores ( <10 μm) surrounding both of the fossils and the living cells proved the existence of some specific receptor sites which bind metal carrier ligands at the microbic surface. The bioaccumulation efficiency of neodymium by the algae cells was 10 times higher for immobilized algae cells. It confirms the fact that the algae immobilization is an useful technique to improve its metal bioaccumulation.

  1. Microspectroscopy of the photosynthetic compartment of algae.

    PubMed

    Evangelista, Valtere; Frassanito, Anna Maria; Passarelli, Vincenzo; Barsanti, Laura; Gualtieri, Paolo

    2006-01-01

    We performed microspectroscopic evaluation of the pigment composition of the photosynthetic compartments of algae belonging to different taxonomic divisions and higher plants. The feasibility of microspectroscopy for discriminating among species and/or phylogenetic groups was tested on laboratory cultures. Gaussian bands decompositions and a fitting algorithm, together with fourth-derivative transformation of absorbance spectra, provided a reliable discrimination among chlorophylls a, b and c, phycobiliproteins and carotenoids. Comparative analysis of absorption spectra highlighted the evolutionary grouping of the algae into three main lineages in accordance with the most recent endosymbiotic theories.

  2. An Overview of Algae Biofuel Production and Potential Environmental Impact

    EPA Science Inventory

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas)...

  3. WASP7 BENTHIC ALGAE - MODEL THEORY AND USER'S GUIDE

    EPA Science Inventory

    The standard WASP7 eutrophication module includes nitrogen and phosphorus cycling, dissolved oxygen-organic matter interactions, and phytoplankton kinetics. In many shallow streams and rivers, however, the attached algae (benthic algae, or periphyton, attached to submerged substr...

  4. Use of Brown Algae to Demonstrate Natural Products Techniques.

    ERIC Educational Resources Information Center

    Porter, Lee A.

    1985-01-01

    Background information is provided on the natural products found in marine organisms in general and the brown algae in particular. Also provided are the procedures needed to isolate D-mannitol (a primary metabolite) and cholesterol from brown algae. (JN)

  5. 21 CFR 73.275 - Dried algae meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture broth... suitable fermentation, under controlled conditions, from a pure culture of the genus Spongiococcum....

  6. 21 CFR 73.275 - Dried algae meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture broth... suitable fermentation, under controlled conditions, from a pure culture of the genus Spongiococcum....

  7. 21 CFR 73.275 - Dried algae meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... algae meal is a dried mixture of algae cells (genus Spongiococcum, separated from its culture broth... suitable fermentation, under controlled conditions, from a pure culture of the genus Spongiococcum....

  8. Photodegradation of Norfloxacin in aqueous solution containing algae.

    PubMed

    Zhang, Junwei; Fu, Dafang; Wu, Jilong

    2012-01-01

    Photodegradation of Norfloxacin in aqueous solution containing algae under a medium pressure mercury lamp (15 W, lambda(max) = 365 nm) was investigated. Results indicated that the photodegradation of Norfloxacin could be induced by the algae in the heterogeneous algae-water systems. The photodegradation rate of Norfloxacin increased with increasing algae concentration, and was greatly influenced by the temperature and pH of solution. Meanwhile, the cooperation action of algae and Fe(III), and the ultrasound were beneficial to photodegradation of Norfloxacin. The degradation kinetics of Norfloxacin was found to follow the pseudo zero-order reaction in the suspension of algae. In addition, we discussed the photodegradation mechanism of Norfloxacin in the suspension of algae. This work will be helpful for understanding the photochemical degradation of antibiotics in aqueous environment in the presence of algae, for providing a new method to deal with antibiotics pollution.

  9. Spatial and temporal dynamics of fucoid populations (Ascophyllum nodosum and Fucus serratus): a comparison between central and range edge populations.

    PubMed

    Araújo, Rita M; Serrão, Ester A; Sousa-Pinto, Isabel; Åberg, Per

    2014-01-01

    Persistence of populations at range edges relies on local population dynamics and fitness, in the case of geographically isolated populations of species with low dispersal potential. Focusing on spatial variations in demography helps to predict the long-term capability for persistence of populations across the geographical range of species' distribution. The demography of two ecological and phylogenetically close macroalgal species with different life history characteristics was investigated by using stochastic, stage-based matrix models. Populations of Ascophyllum nodosum and Fucus serratus were sampled for up to 4 years at central locations in France and at their southern range limits in Portugal. The stochastic population growth rate (λ(s)) of A. nodosum was lower and more variable in central than in southern sites whilst for F. serratus this trend was reversed with λ(s) much lower and more variable in southern than in central populations. Individuals were larger in central than in southern populations for both species, which was reflected in the lower transition probabilities of individuals to larger size classes and higher probability of shrinkage in the southern populations. In both central and southern populations elasticity analysis (proportional sensitivity) of population growth rate showed that fertility elements had a small contribution to λ(s) that was more sensitive to changes in matrix transitions corresponding to survival. The highest elasticities were found for loop transitions in A. nodosum and for growth to larger size classes in F. serratus. Sensitivity analysis showed high selective pressure on individual growth for both species at both locations. The results of this study highlight the deterministic role of species-specific life-history traits in population demography across the geographical range of species. Additionally, this study demonstrates that individuals' life-transitions differ in vulnerability to environmental variability and

  10. Neonatal sepsis caused by Shewanella algae: A case report.

    PubMed

    Charles, Marie Victor Pravin; Srirangaraj, Sreenivasan; Kali, Arunava

    2015-01-01

    Sepsis remains a leading cause of mortality among neonates, especially in developing countries. Most cases of neonatal sepsis are attributed to Escherichia coli and other members of the Enterobacteriaceae family. Shewanella algae (S. algae) is a gram-negative saprophytic bacillus, commonly associated with the marine environment, which has been isolated from humans. Early onset neonatal sepsis caused by S. algae is uncommon. We report a case of S. algae blood stream infection in a newborn with early onset neonatal sepsis.

  11. Effect of Ocean acidification on growth, calcification and reproduction of calcifying and non-calcifying epibionts of brown algae

    NASA Astrophysics Data System (ADS)

    Saderne, V.; Wahl, M.

    2012-04-01

    Anthropogenic emissions of CO2 are leading to an acidification of the oceans of 0.4 pH units in the course of this century according to the more severe model scenarios. The excess of CO2 could notably affect the benthic communities of calcifiers and macrophytes in different aspects (photosynthesis, respiration and calcification). Seaweeds are one of the key species of nearshore benthic ecosystems of the Baltic Sea. They are the substratum of several fouling epibionts like bryozoans and tubeworms. Most of those species are bearing calcified structures and could therefore be potentially impacted by the seawater pCO2. On the other hand, the biological activity of the host may substantially modulate the pH and pCO2 conditions in the boundary layer where the epibionts live. The aim of the present study was to test the sensitivity of seaweed macrofouling communities to higher pCO2 concentration. Fragments of macroalgae Fucus serratus bearing the calcifiers Spirorbis spirorbis (Annelida) and Electra pilosa (Bryozoa) and the non-calcifier Alcyonidium gelatinosum (Bryozoa) were maintained for 30 days under three pCO2: natural 460 ± 59 µatm and enriched 1193 ± 166 µatm and 3150 ± 446 µatm. Our study showed a significant reduction of growth rates and reproduction of Spirorbis individuals at the highest pCO2. Tubeworms Juveniles exhibited enhanced calcification of 40 % when in the light compare to dark, presumably due to effect of photosynthetic and respiratory activities of the host alga. Electra colonies showed significantly improved growth rates at 1193 µatm. The overall net dissolution of the communities was significantly higher at 3150 µatm. No effect on Alcyonidium colonies growth rates was observed. Those results suggest a remarkable resistance of the algal macro-epibiontic communities to the most elevated pCO2 predicted for 2100 for open ocean (~1000 µatm) conditions. Concerns remains with regards to higher pCO2 possibly found in the future Baltic Sea.

  12. How to Identify and Control Water Weeds and Algae.

    ERIC Educational Resources Information Center

    Applied Biochemists, Inc., Mequon, WI.

    Included in this guide to water management are general descriptions of algae, toxic algae, weed problems in lakes, ponds, and canals, and general discussions of mechanical, biological and chemical control methods. In addition, pictures, descriptions, and recommended control methods are given for algae, 6 types of floating weeds, 18 types of…

  13. 21 CFR 73.185 - Haematococcus algae meal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the...

  14. 21 CFR 73.185 - Haematococcus algae meal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the...

  15. 21 CFR 73.185 - Haematococcus algae meal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the...

  16. 21 CFR 73.185 - Haematococcus algae meal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the...

  17. 21 CFR 73.185 - Haematococcus algae meal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Haematococcus algae meal. 73.185 Section 73.185... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.185 Haematococcus algae meal. (a) Identity. (1) The color additive haematococcus algae meal consists of the comminuted and dried cells of the...

  18. Research and development for algae-based technologies in Korea: a review of algae biofuel production.

    PubMed

    Hong, Ji Won; Jo, Seung-Woo; Yoon, Ho-Sung

    2015-03-01

    This review covers recent research and development (R&D) activities in the field of algae-based biofuels in Korea. As South Korea's energy policy paradigm has focused on the development of green energies, the government has funded several algae biofuel R&D consortia and pilot projects. Three major programs have been launched since 2009, and significant efforts are now being made to ensure a sustainable supply of algae-based biofuels. If these R&D projects are executed as planned for the next 10 years, they will enable us to overcome many technical barriers in algae biofuel technologies and help Korea to become one of the leading countries in green energy by 2020.

  19. Sterol chemotaxonomy of marine pelagophyte algae.

    PubMed

    Giner, José-Luis; Zhao, Hui; Boyer, Gregory L; Satchwell, Michael F; Andersen, Robert A

    2009-07-01

    Several marine algae of the class Pelagophyceae produce the unusual marine sterol 24-propylidenecholesterol, mainly as the (24E)-isomer. The (24Z)-isomer had previously been considered as a specific biomarker for Aureococcus anophagefferens, the 'brown tide' alga of the Northeast coast of the USA. To test this hypothesis and to generate chemotaxonomic information, the sterol compositions of 42 strains of pelagophyte algae including 17 strains of Aureococcus anophagefferens were determined by GC analysis. A more comprehensive sterol analysis by HPLC and (1)H-NMR was obtained for 17 selected pelagophyte strains. All strains analyzed contained 24-propylidenecholesterol. In all strains belonging to the order Sarcinochrysidales, this sterol was found only as the (E)-isomer, while all strains in the order Pelagomonadales contained the (Z)-isomer, either alone or together with the (E)-isomer. The occurrence of Delta(22) and 24alpha-sterols was limited to the Sarcinochrysidales. The first occurrence of Delta(22)-24-propylcholesterol in an alga, CCMP 1410, was reported. Traces of the rare sterol 26,26-dimethyl-24-methylenecholesterol were detected in Aureococcus anophagefferens, and the (25R)-configuration was proposed, based on biosynthetic considerations. Traces of a novel sterol, 24-propylidenecholesta-5,25-dien-3beta-ol, were detected in several species.

  20. Pheromone signaling during sexual reproduction in algae.

    PubMed

    Frenkel, Johannes; Vyverman, Wim; Pohnert, Georg

    2014-08-01

    Algae are found in all aquatic and many terrestrial habitats. They are dominant in phytoplankton and biofilms thereby contributing massively to global primary production. Since algae comprise photosynthetic representatives of the various protoctist groups their physiology and appearance is highly diverse. This diversity is also mirrored in their characteristic life cycles that exhibit various facets of ploidy and duration of the asexual phase as well as gamete morphology. Nevertheless, sexual reproduction in unicellular and colonial algae usually has as common motive that two specialized, sexually compatible haploid gametes establish physical contact and fuse. To guarantee mating success, processes during sexual reproduction are highly synchronized and regulated. This review focuses on sex pheromones of algae that play a key role in these processes. Especially, the diversity of sexual strategies as well as of the compounds involved are the focus of this contribution. Discoveries connected to algal pheromone chemistry shed light on the role of key evolutionary processes, including endosymbiotic events and lateral gene transfer, speciation and adaptation at all phylogenetic levels. But progress in this field might also in the future provide valid tools for the manipulation of aquaculture and environmental processes.

  1. Research for Developing Renewable Biofuels from Algae

    SciTech Connect

    Black, Paul N.

    2012-12-15

    Task A. Expansion of knowledge related to lipid production and secretion in algae A.1 Lipid biosynthesis in target algal species; Systems biology approaches are being used in combination with recent advances in Chlorella and Chlamydomonas genomics to address lipid accumulation in response to defined nutrient regimes. The UNL Algal Group continues screening additional species of Chlorella and other naturally occurring algae for those with optimal triglyceride production; Of the strains examined by the DOE's Aquatic Species Program, green algae, several species of Chlorella represent the largest group from which oleaginous candidates have been identified; A.1.1. Lipid profiling; Neutral lipid accumulation is routinely monitored by Nile red and BODIPY staining using high throughput strategies to screen for naturally occurring algae that accumulate triglyceride. These strategies complement those using spectrofluorometry to quantify lipid accumulation; Neutral lipid accumulation is routinely monitored by high performance thin-layer chromatography (HPTLC) and high performance liquid chromatography (HPLC) of lipid extracts in conjunction with; Carbon portioning experiments have been completed and the data currently are being analyzed and prepared for publication; Methods in the Black lab were developed to identify and quantify triacylglycerol (TAG), major membrane lipids [diacylglycerol trimethylhomoserine, phosphatidylethanolamine and chloroplast glycolipids], biosynthetic intermediates such as diacylglycerol, phosphatidic acid and lysophospholipids and different species of acyl-coenzyme A (acyl CoA).

  2. Dermatitis from purified sea algae toxin (debromoaplysiatoxin).

    PubMed

    Solomon, A E; Stoughton, R B

    1978-09-01

    Cutaneous inflammation was induced by debromoaplysiatoxin, a purified toxin extracted from Lyngbya majuscula Gomont. This alga causes a seaweed dermatitis that occurs in persons who have swum off the coast of Oahu in Hawaii. By topical application, the toxin was found to produce an irritant pustular folliculitis in humans and to cause a severe cutaneous inflammatory reaction in the rabbit and in hairless mice.

  3. Polyamine biosynthetic diversity in plants and algae.

    PubMed

    Fuell, Christine; Elliott, Katherine A; Hanfrey, Colin C; Franceschetti, Marina; Michael, Anthony J

    2010-07-01

    Polyamine biosynthesis in plants differs from other eukaryotes because of the contribution of genes from the cyanobacterial ancestor of the chloroplast. Plants possess an additional biosynthetic route for putrescine formation from arginine, consisting of the enzymes arginine decarboxylase, agmatine iminohydrolase and N-carbamoylputrescine amidohydrolase, derived from the cyanobacterial ancestor. They also synthesize an unusual tetraamine, thermospermine, that has important developmental roles and which is evolutionarily more ancient than spermine in plants and algae. Single-celled green algae have lost the arginine route and are dependent, like other eukaryotes, on putrescine biosynthesis from the ornithine. Some plants like Arabidopsis thaliana and the moss Physcomitrella patens have lost ornithine decarboxylase and are thus dependent on the arginine route. With its dependence on the arginine route, and the pivotal role of thermospermine in growth and development, Arabidopsis represents the most specifically plant mode of polyamine biosynthesis amongst eukaryotes. A number of plants and algae are also able to synthesize unusual polyamines such as norspermidine, norspermine and longer polyamines, and biosynthesis of these amines likely depends on novel aminopropyltransferases similar to thermospermine synthase, with relaxed substrate specificity. Plants have a rich repertoire of polyamine-based secondary metabolites, including alkaloids and hydroxycinnamic amides, and a number of polyamine-acylating enzymes have been recently characterised. With the genetic tools available for Arabidopsis and other model plants and algae, and the increasing capabilities of comparative genomics, the biological roles of polyamines can now be addressed across the plant evolutionary lineage.

  4. Bromophenols in Marine Algae and Their Bioactivities

    PubMed Central

    Liu, Ming; Hansen, Poul Erik; Lin, Xiukun

    2011-01-01

    Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect to structure, bioactivities, and their potential application as pharmaceuticals. PMID:21822416

  5. [Allelopathic effect of artemisinin on green algae].

    PubMed

    Wu, Ye-Kuan; Yuan, Ling; Huang, Jian-Guo; Li, Long-Yun

    2013-05-01

    To study the growth effects of differing concentrations of artemisinin on green algae and to evaluate the ecological risk. The effects of artemisinin on the growth and the content change of chlorophyll, protein, oxygen, conductivity, SOD, CAT, MDA in Chlorella pyrenoidosa and Scenedesmus oblique were studied through 96 h toxicity tests. Artemisinin accelerated the growth of algae at a lower concentration ( <40 microg . L-1) with content increase of chlorophyll or protein and so on, and it inhibited the growth of algae at higher concentration ( >80 microg . L-1). The content of chlorophyll or protein in algae cells reduced with the increasing concentration of artemisinin, exhibiting the good concentration-effect relationship. SOD and CAT activity was stimulated at low concentrations ( <40 microg . L-1 ) and inhibited at high concentrations ( >80 microg . L- 1). However, MDA content increased significantly with the increase of concentration. According to the seven kinds of indicators changes, the time-response and dose-response suggested that the surfactant first hurt in Ch. pyrenoidosa was damaging membrane by changing membrane lipid molecules soluble. And primary mechanism on Chlorophyta cells might be related to the oxidation damage of lipid and other biological large molecules caused by artemisinin. The large-scale intensive planting of Artemisia annua may reduce the surrounding water productivity.

  6. Laser-fluorescence measurement of marine algae

    NASA Technical Reports Server (NTRS)

    Browell, E. V.

    1980-01-01

    Progress in remote sensing of algae by laser-induced fluorescence is subject of comprehensive report. Existing single-wavelength and four-wavelength systems are reviewed, and new expression for power received by airborne sensor is derived. Result differs by as much as factor of 10 from those previously reported. Detailed error analysis evluates factors affecting accuracy of laser-fluorosensor systems.

  7. Fucoidans — sulfated polysaccharides of brown algae

    NASA Astrophysics Data System (ADS)

    Usov, Anatolii I.; Bilan, M. I.

    2009-08-01

    The methods of isolation of fucoidans and determination of their chemical structures are reviewed. The fucoidans represent sulfated polysaccharides of brown algae, the composition of which varies from simple fucan sulfates to complex heteropolysaccharides. The currently known structures of such biopolymers are presented. A variety of the biological activities of fucoidans is briefly summarised.

  8. Spirulina: The Alga That Can End Malnutrition.

    ERIC Educational Resources Information Center

    Fox, Ripley D.

    1985-01-01

    One approach to eliminating malnutrition worldwide is to grow spirulina in recycled village wastes. Spirulina is a blue-green alga and a natural concentrated food. Spirulina can give poor villages a nutritional food supplement they can grow themselves and can reduce infectious disease at the same time. (Author/RM)

  9. A protective coat of microorganisms on macroalgae: inhibitory effects of bacterial biofilms and epibiotic microbial assemblages on barnacle attachment.

    PubMed

    Nasrolahi, Ali; Stratil, Stephanie B; Jacob, Katharina J; Wahl, Martin

    2012-09-01

    Effects of epibiotic bacteria associated with macroalgae on barnacle larval attachment were investigated. Eight bacterial isolates obtained from samples of three macroalga species were cultured as monospecies bacterial films and tested for their activity against barnacle (Amphibalanus improvisus) attachment in field experiments (Western Baltic Sea). Furthermore, natural biofilm communities associated with the surface of the local brown alga, Fucus vesiculosus, which were exposed to different temperatures (5, 15 and 20 °C), were harvested and subsequently tested. Generally, monospecies bacterial biofilms, as well as natural microbial assemblages, inhibited barnacle attachment by 20-67%. denaturing gradient gel electrophoresis fingerprints showed that temperature treatment shifted the bacterial community composition and weakened the repellent effects at 20 °C. Repellent effects were absent when settlement pressure of cyprids was high. Nonviable bacteria tended to repel cyprids when compared to the unfilmed surfaces. We conclude that biofilms can have a repellent effect benefiting the host by preventing heavy fouling on its surface. However, severe settlement pressure, as well as stressful temperature, may reduce the protective effects of the alga's biofilm. Our results add to the notion that the performance of F. vesiculosus may be reduced by multiple stressors in the course of global warming.

  10. A review on biosynthesis of nanoparticles by marine organisms.

    PubMed

    Asmathunisha, N; Kathiresan, K

    2013-03-01

    Marine organisms produce remarkable nanofabricated structures in cell wall, shells, pearls and fish bones. Marine microorganisms such as bacteria (E. coli, Pseudomonas sp.), cyanobacteria (Spirulina platensis, Oscillatoria willei, Phormidium tenue), yeasts (Pichia capsulata, Rhodospiridium diobovatum), fungi (Thraustochytrium sp., Penicillium fellutanum, Aspergillus niger), and algae (Navicula atomus, Diadesmis gallica, Stauroneis sp. Sargassum wightii, Fucus vesiculosus) are reported to synthesize inorganic nanoparticles either inside or outside cells. Mangroves (Rhizophora mucronata, Xylocarpus mekongensis), salt marshes (Sesuvium portulacastrum and Suaeda sp.) and sand dune (Citrullus colocynthis) are also capable of synthesizing the nanoparticles, in addition to marine animals such as finfish and sponges. Biosynthesis of nanoparticles may be triggered by several compounds such as carbonyl groups, terpenoids, phenolics, flavonones, amines, amides, proteins, pigments, alkaloids and other reducing agents present in the biological extracts. Marine bio-nanotechnology has a great promise in nanomedicines, food stuff, pharmaceuticals and fabric industries for the future.

  11. Sulfated polysaccharides as bioactive agents from marine algae.

    PubMed

    Ngo, Dai-Hung; Kim, Se-Kwon

    2013-11-01

    Recently, much attention has been paid by consumers toward natural bioactive compounds as functional ingredients in nutraceuticals. Marine algae are considered as valuable sources of structurally diverse bioactive compounds. Marine algae are rich in sulfated polysaccharides (SPs) such as carrageenans in red algae, fucoidans in brown algae and ulvans in green algae. These SPs exhibit many health beneficial nutraceutical effects such as antioxidant, anti-allergic, anti-human immunodeficiency virus, anticancer and anticoagulant activities. Therefore, marine algae derived SPs have great potential to be further developed as medicinal food products or nutraceuticals in the food industry. This contribution presents an overview of nutraceutical effects and potential health benefits of SPs derived from marine algae.

  12. Effect of Ocean acidification on growth, calcification and recruitment of calcifying and non-calcifying epibionts of brown algae

    NASA Astrophysics Data System (ADS)

    Saderne, V.; Wahl, M.

    2012-03-01

    Anthropogenic emissions of CO2 are leading to an acidification of the oceans by 0.4 pH units in the course of this century according to the more severe model scenarios. The excess of CO2 could notably affect the benthic communities of calcifiers and macrophytes in different aspects (photosynthesis, respiration and calcification). Seaweeds are key species of nearshore benthic ecosystems of the Baltic Sea. They frequently are the substratum of fouling epibionts like bryozoans and tubeworms. Most of those species secrete calcified structures and could therefore be impacted by the seawater pCO2. On the other hand, the biological activity of the host may substantially modulate the pH and pCO2 conditions in the thallus boundary layer where the epibionts live. The aim of the present study was to test the sensitivity of seaweed macrofouling communities to higher pCO2 concentrations. Fragments of the macroalga Fucus serratus bearing the calcifiers Spirorbis spirorbis (Annelida) and Electra pilosa (Bryozoa) and the non-calcifier Alcyonidium gelatinosum (Bryozoa) were maintained for 30 days under three pCO2 conditions: natural 460 ± 59 μatm and enriched 1193 ± 166 μatm and 3150 ± 446 μatm. Our study showed a significant reduction of growth rates and recruitment of Spirorbis individuals only at the highest pCO2. At a finer temporal resolution, the tubeworm recruits exhibited enhanced calcification of 40% during irradiation hours compared to dark hours, presumably due to the effect of photosynthetic and respiratory activities of the host alga on the carbonate system. Electra colonies showed significantly increased growth rates at 1193 μatm. No effect on Alcyonidium colonies growth rates was observed. Those results suggest a remarkable resistance of the algal macro-epibiontic communities to the most elevated pCO2 foreseen in year 2100 for open ocean (~1000 μatm) conditions possibly due to the modulation of environmental conditions by the biological activities of the host

  13. Biofuels from algae: challenges and potential.

    PubMed

    Hannon, Michael; Gimpel, Javier; Tran, Miller; Rasala, Beth; Mayfield, Stephen

    2010-09-01

    Algae biofuels may provide a viable alternative to fossil fuels; however, this technology must overcome a number of hurdles before it can compete in the fuel market and be broadly deployed. These challenges include strain identification and improvement, both in terms of oil productivity and crop protection, nutrient and resource allocation and use, and the production of co-products to improve the economics of the entire system. Although there is much excitement about the potential of algae biofuels, much work is still required in the field. In this article, we attempt to elucidate the major challenges to economic algal biofuels at scale, and improve the focus of the scientific community to address these challenges and move algal biofuels from promise to reality.

  14. Hydrogen production by photosynthetic green algae.

    PubMed

    Ghirardi, Maria L

    2006-08-01

    Oxygenic photosynthetic organisms such as cyanobacteria, green algae and diatoms are capable of absorbing light and storing up to 10-13% of its energy into the H-H bond of hydrogen gas. This process, which takes advantage of the photosynthetic apparatus of these organisms to convert sunlight into chemical energy, could conceivably be harnessed for production of significant amounts of energy from a renewable resource, water. The harnessed energy could then be coupled to a fuel cell for electricity generation and recycling of water molecules. In this review, current biochemical understanding of this reaction in green algae, and some of the major challenges facing the development of future commercial algal photobiological systems for H2 production have been discussed.

  15. Engineering algae for biohydrogen and biofuel production.

    PubMed

    Beer, Laura L; Boyd, Eric S; Peters, John W; Posewitz, Matthew C

    2009-06-01

    There is currently substantial interest in utilizing eukaryotic algae for the renewable production of several bioenergy carriers, including starches for alcohols, lipids for diesel fuel surrogates, and H2 for fuel cells. Relative to terrestrial biofuel feedstocks, algae can convert solar energy into fuels at higher photosynthetic efficiencies, and can thrive in salt water systems. Recently, there has been considerable progress in identifying relevant bioenergy genes and pathways in microalgae, and powerful genetic techniques have been developed to engineer some strains via the targeted disruption of endogenous genes and/or transgene expression. Collectively, the progress that has been realized in these areas is rapidly advancing our ability to genetically optimize the production of targeted biofuels.

  16. Biofuels from algae: challenges and potential

    PubMed Central

    Hannon, Michael; Gimpel, Javier; Tran, Miller; Rasala, Beth; Mayfield, Stephen

    2011-01-01

    Algae biofuels may provide a viable alternative to fossil fuels; however, this technology must overcome a number of hurdles before it can compete in the fuel market and be broadly deployed. These challenges include strain identification and improvement, both in terms of oil productivity and crop protection, nutrient and resource allocation and use, and the production of co-products to improve the economics of the entire system. Although there is much excitement about the potential of algae biofuels, much work is still required in the field. In this article, we attempt to elucidate the major challenges to economic algal biofuels at scale, and improve the focus of the scientific community to address these challenges and move algal biofuels from promise to reality. PMID:21833344

  17. Algae-Derived Dietary Ingredients Nourish Animals

    NASA Technical Reports Server (NTRS)

    2015-01-01

    In the 1980s, Columbia, Maryland-based Martek Biosciences Corporation worked with Ames Research Center to pioneer the use of microalgae as a source of essential omega-3 fatty acids, work that led the company to develop its highly successful Formulaid product. Now the Nutritional Products Division of Royal DSM, the company also manufactures DHAgold, a nutritional supplement for pets, livestock and farm-raised fish that uses algae to deliver docosahexaenoic acid (DHA).

  18. Selenium Uptake and Volatilization by Marine Algae

    NASA Astrophysics Data System (ADS)

    Luxem, Katja E.; Vriens, Bas; Wagner, Bettina; Behra, Renata; Winkel, Lenny H. E.

    2015-04-01

    Selenium (Se) is an essential trace nutrient for humans. An estimated one half to one billion people worldwide suffer from Se deficiency, which is due to low concentrations and bioavailability of Se in soils where crops are grown. It has been hypothesized that more than half of the atmospheric Se deposition to soils is derived from the marine system, where microorganisms methylate and volatilize Se. Based on model results from the late 1980s, the atmospheric flux of these biogenic volatile Se compounds is around 9 Gt/year, with two thirds coming from the marine biosphere. Algae, fungi, and bacteria are known to methylate Se. Although algal Se uptake, metabolism, and methylation influence the speciation and bioavailability of Se in the oceans, these processes have not been quantified under environmentally relevant conditions and are likely to differ among organisms. Therefore, we are investigating the uptake and methylation of the two main inorganic Se species (selenate and selenite) by three globally relevant microalgae: Phaeocystis globosa, the coccolithophorid Emiliania huxleyi, and the diatom Thalassiosira oceanica. Selenium uptake and methylation were quantified in a batch experiment, where parallel gas-tight microcosms in a climate chamber were coupled to a gas-trapping system. For E. huxleyi, selenite uptake was strongly dependent on aqueous phosphate concentrations, which agrees with prior evidence that selenite uptake by phosphate transporters is a significant Se source for marine algae. Selenate uptake was much lower than selenite uptake. The most important volatile Se compounds produced were dimethyl selenide, dimethyl diselenide, and dimethyl selenyl sulfide. Production rates of volatile Se species were larger with increasing intracellular Se concentration and in the decline phase of the alga. Similar experiments are being carried out with P. globosa and T. oceanica. Our results indicate that marine algae are important for the global cycling of Se

  19. Algae: America’s Pathway to Independence

    DTIC Science & Technology

    2007-03-30

    Bioenergy, Biofuel, Energy Policy CLASSIFICATION: Unclassified The United States is dependent on foreign oil to meet 63% of its petroleum demand...source of bioenergy. ALGAE: AMERICA’S PATHWAY TO INDEPENDENCE Ensuring a secure supply of energy is a strategic challenge for...150 years,6 the U.S. will be competing with other nations to procure the 2 finite commodity. The Department of Energy (DOE) estimates that by the

  20. Algae as Reservoirs for Coral Pathogens

    PubMed Central

    Sweet, Michael J.; Bythell, John C.; Nugues, Maggy M.

    2013-01-01

    Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS) in the Indo-Pacific and Yellow Band Disease (YBD) in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively). Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is most likely a

  1. [Pharmacology and toxicology of Spirulina alga].

    PubMed

    Chamorro, G; Salazar, M; Favila, L; Bourges, H

    1996-01-01

    Spirulina, a unicellular filamentous blue-green alga has been consumed by man since ancient times in Mexico and central Africa. It is currently grown in many countries by synthetic methods. Initially the interest in Spirulina was on its nutritive value: it was found almost equal to other plant proteins. More recently, some preclinical testing suggests it has several therapeutic properties such as hypocholesterolemic, immunological, antiviral and antimutagenic. This has led to more detailed evaluations such as nucleic acid content and presence of toxic metals, biogenic toxins and organic chemicals: they have shown absence or presence at tolerable levels according to the recommendations of international regulatory agencies. In animal experiments for acute, subchronic and chronic toxicity, reproduction, mutagenicity, and teratogenicity the algae did not cause body or organ toxicity. In all instances, the Spirulina administered to the animals were at much higher amounts than those expected for human consumption. On the other hand there is scant information of the effects of the algae in humans. This area needs more research.

  2. New records of marine algae in Vietnam

    NASA Astrophysics Data System (ADS)

    Le Hau, Nhu; Ly, Bui Minh; Van Huynh, Tran; Trung, Vo Thanh

    2015-06-01

    In May, 2013, a scientific expedition was organized by the Vietnam Academy of Science and Technology (VAST) and the Far Eastern Branch of the Russian Academy of Sciences (FEBRAS) through the frame of the VAST-FEBRAS International Collaboration Program. The expedition went along the coast of Vietnam from Quang Ninh to Kien Giang. The objective was to collect natural resources to investigate the biological and biochemical diversity of the territorial waters of Vietnam. Among the collected algae, six taxa are new records for the Vietnam algal flora. They are the red algae Titanophora pikeana (Dickie) Feldmann from Cu Lao Xanh Island, Laurencia natalensis Kylin from Tho Chu Island, Coelothrix irregularis (Harvey) Børgesen from Con Dao Island, the green algae Caulerpa oligophylla Montagne, Caulerpa andamanensis (W.R. Taylor) Draisma, Prudhomme et Sauvage from Phu Quy Island, and Caulerpa falcifolia Harvey & Bailey from Ly Son Island. The seaweed flora of Vietnam now counts 833 marine algal taxa, including 415 Rhodophyta, 147 Phaeophyceae, 183 Chlorophyta, and 88 Cyanobacteria.

  3. Screening for bioactive compounds from algae.

    PubMed

    Plaza, M; Santoyo, S; Jaime, L; García-Blairsy Reina, G; Herrero, M; Señoráns, F J; Ibáñez, E

    2010-01-20

    In the present work, a comprehensive methodology to carry out the screening for novel natural functional compounds is presented. To do that, a new strategy has been developed including the use of unexplored natural sources (i.e., algae and microalgae) together with environmentally clean extraction techniques and advanced analytical tools. The developed procedure allows also estimating the functional activities of the different extracts obtained and even more important, to correlate these activities with their particular chemical composition. By applying this methodology it has been possible to carry out the screening for bioactive compounds in the algae Himanthalia elongata and the microalgae Synechocystis sp. Both algae produced active extracts in terms of both antioxidant and antimicrobial activity. The obtained pressurized liquid extracts were chemically characterized by GC-MS and HPLC-DAD. Different fatty acids and volatile compounds with antimicrobial activity were identified, such as phytol, fucosterol, neophytadiene or palmitic, palmitoleic and oleic acids. Based on the results obtained, ethanol was selected as the most appropriate solvent to extract this kind of compounds from the natural sources studied.

  4. Antibody Production in Plants and Green Algae.

    PubMed

    Yusibov, Vidadi; Kushnir, Natasha; Streatfield, Stephen J

    2016-04-29

    Monoclonal antibodies (mAbs) have a wide range of modern applications, including research, diagnostic, therapeutic, and industrial uses. Market demand for mAbs is high and continues to grow. Although mammalian systems, which currently dominate the biomanufacturing industry, produce effective and safe recombinant mAbs, they have a limited manufacturing capacity and high costs. Bacteria, yeast, and insect cell systems are highly scalable and cost effective but vary in their ability to produce appropriate posttranslationally modified mAbs. Plants and green algae are emerging as promising production platforms because of their time and cost efficiencies, scalability, lack of mammalian pathogens, and eukaryotic posttranslational protein modification machinery. So far, plant- and algae-derived mAbs have been produced predominantly as candidate therapeutics for infectious diseases and cancer. These candidates have been extensively evaluated in animal models, and some have shown efficacy in clinical trials. Here, we review ongoing efforts to advance the production of mAbs in plants and algae.

  5. Environmental life cycle comparison of algae to other bioenergy feedstocks.

    PubMed

    Clarens, Andres F; Resurreccion, Eleazer P; White, Mark A; Colosi, Lisa M

    2010-03-01

    Algae are an attractive source of biomass energy since they do not compete with food crops and have higher energy yields per area than terrestrial crops. In spite of these advantages, algae cultivation has not yet been compared with conventional crops from a life cycle perspective. In this work, the impacts associated with algae production were determined using a stochastic life cycle model and compared with switchgrass, canola, and corn farming. The results indicate that these conventional crops have lower environmental impacts than algae in energy use, greenhouse gas emissions, and water regardless of cultivation location. Only in total land use and eutrophication potential do algae perform favorably. The large environmental footprint of algae cultivation is driven predominantly by upstream impacts, such as the demand for CO(2) and fertilizer. To reduce these impacts, flue gas and, to a greater extent, wastewater could be used to offset most of the environmental burdens associated with algae. To demonstrate the benefits of algae production coupled with wastewater treatment, the model was expanded to include three different municipal wastewater effluents as sources of nitrogen and phosphorus. Each provided a significant reduction in the burdens of algae cultivation, and the use of source-separated urine was found to make algae more environmentally beneficial than the terrestrial crops.

  6. Electro-coagulation-flotation process for algae removal.

    PubMed

    Gao, Shanshan; Yang, Jixian; Tian, Jiayu; Ma, Fang; Tu, Gang; Du, Maoan

    2010-05-15

    Algae in surface water have been a long-term issue all over the world, due to their adverse influence on drinking water treatment process as well as drinking water quality. The algae removal by electro-coagulation-flotation (ECF) technology was investigated in this paper. The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron. The optimal parameters determined were: current density=1 mA/cm(2), pH=4-7, water temperature=18-36 degrees C, algae density=0.55 x 10(9)-1.55 x 10(9) cells/L. Under the optimal conditions, 100% of algae removal was achieved with the energy consumption as low as 0.4 kWh/m(3). The ECF performed well in acid and neutral conditions. At low initial pH of 4-7, the cell density of algae was effectively removed in the ECF, mainly through the charge neutralization mechanism; while the algae removal worsened when the pH increased (7-10), and the main mechanism shifted to sweeping flocculation and enmeshment. The mechanisms for algae removal at different pH were also confirmed by atomic force microscopy (AFM) analysis. Furthermore, initial cell density and water temperature could also influence the algae removal. Overall, the results indicated that the ECF technology was effective for algae removal, from both the technical and economical points of view.

  7. Exploring the potential of algae/bacteria interactions.

    PubMed

    Kouzuma, Atsushi; Watanabe, Kazuya

    2015-06-01

    Algae are primary producers in aquatic ecosystems, where heterotrophic bacteria grow on organics produced by algae and recycle nutrients. Ecological studies have identified the co-occurrence of particular species of algae and bacteria, suggesting the presence of their specific interactions. Algae/bacteria interactions are categorized into nutrient exchange, signal transduction and gene transfer. Studies have examined how these interactions shape aquatic communities and influence geochemical cycles in the natural environment. In parallel, efforts have been made to exploit algae for biotechnology processes, such as water treatment and bioenergy production, where bacteria influence algal activities in various ways. We suggest that better understanding of mechanisms underlying algae/bacteria interactions will facilitate the development of more efficient and/or as-yet-unexploited biotechnology processes.

  8. Algae to Bio-Crude in Less Than 60 Minutes

    ScienceCinema

    Elliott, Doug

    2016-07-12

    Engineers have created a chemical process that produces useful crude oil just minutes after engineers pour in harvested algae -- a verdant green paste with the consistency of pea soup. The PNNL team combined several chemical steps into one continuous process that starts with an algae slurry that contains as much as 80 to 90 percent water. Most current processes require the algae to be dried -- an expensive process that takes a lot of energy. The research has been licensed by Genifuel Corp.

  9. Algae to Bio-Crude in Less Than 60 Minutes

    SciTech Connect

    Elliott, Doug

    2013-12-17

    Engineers have created a chemical process that produces useful crude oil just minutes after engineers pour in harvested algae -- a verdant green paste with the consistency of pea soup. The PNNL team combined several chemical steps into one continuous process that starts with an algae slurry that contains as much as 80 to 90 percent water. Most current processes require the algae to be dried -- an expensive process that takes a lot of energy. The research has been licensed by Genifuel Corp.

  10. Method and apparatus for iterative lysis and extraction of algae

    DOEpatents

    Chew, Geoffrey; Boggs, Tabitha; Dykes, Jr., H. Waite H.; Doherty, Stephen J.

    2015-12-01

    A method and system for processing algae involves the use of an ionic liquid-containing clarified cell lysate to lyse algae cells. The resulting crude cell lysate may be clarified and subsequently used to lyse algae cells. The process may be repeated a number of times before a clarified lysate is separated into lipid and aqueous phases for further processing and/or purification of desired products.

  11. Freshwater Cyanobacteria (Blue-Green Algae) Toxins: Isolation and Characterization

    DTIC Science & Technology

    1990-05-01

    division Cyanophyta , commonly called blue -green algae cr cyanobacteria . Although cyanobacteria are found in almost any environment ranging from hot...p ecst Available Copy ~’ COPy Ni AD FRESHWATER CYANOBACTERIA ( BLUE -GREEN ALGAE ) TOXINS:’ I ISOLATION AND CHARACTERIZATION < DTIC ANNUAL/FINAL...AA I 78 11. TITLE (In•.ju . ’,curry Ci.si fication) Freshwater Cyanobacteria ( blue -green algae ) Toxins: Isolatior and CharacteriZation 12. PERSONAL

  12. Freshwater Cyanobacteria (Blue-Green Algae) Toxins: Isolation and Characterization

    DTIC Science & Technology

    1989-01-15

    exclusively caused by strains of species that are members of the L division Cyanophyta , commonly called blue -green algae or cyanobacteria . Although...0 0 Lfl (NAD FRESHWATER CYANOBACTERIA ( BLUE -GREEN ALGAE ) TOXINS: ISOLATION AND CHARACTERIZATION ANNCUAL REPORT Wayne W. Carmichael Sarojini Bose...Frederick, Maryland 21701-5012 62770A 6277GA871 AA 378 11 TITLE &who* Secwn~y C11mrfaon) Freshwater Cyanobacteria ( blue -green algae ) Toxins: Isolation

  13. Method for producing hydrogen and oxygen by use of algae

    DOEpatents

    Greenbaum, Elias

    1984-01-01

    Efficiency of process for producing H.sub.2 by subjecting algae in an aqueous phase to light irradiation is increased by culturing algae which has been bleached during a first period of irradiation in a culture medium in an aerobic atmosphere until it has regained color and then subjecting this algae to a second period of irradiation wherein hydrogen is produced at an enhanced rate.

  14. Method for producing hydrogen and oxygen by use of algae

    DOEpatents

    Greenbaum, E.

    1982-06-16

    Efficiency of process for producing H/sub 2/ by subjecting algae in an aqueous phase to light irradiation is increased by culturing algae which has been bleached during a first period of irradiation in a culture medium in an aerobic atmosphere until it has regained color and then subjecting this algae to a second period of irradiation wherein hydrogen is produced at an enhanced rate.

  15. Bromophenols from marine algae with potential anti-diabetic activities

    NASA Astrophysics Data System (ADS)

    Lin, Xiukun; Liu, Ming

    2012-12-01

    Marine algae contain various bromophenols with a variety of biological activities, including antimicrobial, anticancer, and anti-diabetic effects. Here, we briefly review the recent progress in researches on the biomaterials from marine algae, emphasizing the relationship between the structure and the potential anti-diabetic applications. Bromophenols from marine algae display their hyperglycemic effects by inhibiting the activities of protein tyrosine phosphatase 1B, α-glucosidase, as well as other mechanisms.

  16. Overall Energy Considerations for Algae Species Comparison and Selection in Algae-to-Fuels Processes

    SciTech Connect

    Link, D.; Kail, B.; Curtis, W.; Tuerk,A.

    2011-01-01

    The controlled growth of microalgae as a feedstock for alternative transportation fuel continues to receive much attention. Microalgae have the characteristics of rapid growth rate, high oil (lipid) content, and ability to be grown in unconventional scenarios. Algae have also been touted as beneficial for CO{sub 2} reuse, as algae can be grown using CO{sub 2} emissions from fossil-based energy generation. Moreover, algae does not compete in the food chain, lessening the 'food versus fuel' debate. Most often, it is assumed that either rapid production rate or high oii content should be the primary factor in algae selection for algae-to-fuels production systems. However, many important characteristics of algae growth and lipid production must be considered for species selection, growth condition, and scale-up. Under light limited, high density, photoautotrophic conditions, the inherent growth rate of an organism does not affect biomass productivity, carbon fixation rate, and energy fixation rate. However, the oil productivity is organism dependent, due to physiological differences in how the organisms allocate captured photons for growth and oil production and due to the differing conditions under which organisms accumulate oils. Therefore, many different factors must be considered when assessing the overall energy efficiency of fuel production for a given algae species. Two species, Chlorella vulgaris and Botryococcus braunii, are popular choices when discussing algae-to-fuels systems. Chlorella is a very robust species, often outcompeting other species in mixed-culture systems, and produces a lipid that is composed primarily of free fatty acids and glycerides. Botryococcus is regarded as a slower growing species, and the lipid that it produces is characterized by high hydrocarbon content, primarily C28-C34 botryococcenes. The difference in growth rates is often considered to be an advantage oiChlorella. However, the total energy captured by each algal species in

  17. Application of synthetic biology in cyanobacteria and algae.

    PubMed

    Wang, Bo; Wang, Jiangxin; Zhang, Weiwen; Meldrum, Deirdre R

    2012-01-01

    Cyanobacteria and algae are becoming increasingly attractive cell factories for producing renewable biofuels and chemicals due to their ability to capture solar energy and CO(2) and their relatively simple genetic background for genetic manipulation. Increasing research efforts from the synthetic biology approach have been made in recent years to modify cyanobacteria and algae for various biotechnological applications. In this article, we critically review recent progresses in developing genetic tools for characterizing or manipulating cyanobacteria and algae, the applications of genetically modified strains for synthesizing renewable products such as biofuels and chemicals. In addition, the emergent challenges in the development and application of synthetic biology for cyanobacteria and algae are also discussed.

  18. Method and apparatus for lysing and processing algae

    SciTech Connect

    Chew, Geoffrey; Reich, Alton J.; Dykes, Jr., H. Waite H.; Di Salvo, Roberto

    2013-03-05

    Methods and apparatus for processing algae are described in which a hydrophilic ionic liquid is used to lyse algae cells at lower temperatures than existing algae processing methods. A salt or salt solution is used as a separation agent and to remove water from the ionic liquid, allowing the ionic liquid to be reused. The used salt may be dried or concentrated and reused. The relatively low lysis temperatures and recycling of the ionic liquid and salt reduce the environmental impact of the algae processing while providing biofuels and other useful products.

  19. Algae Bioreactor Using Submerged Enclosures with Semi-Permeable Membranes

    NASA Technical Reports Server (NTRS)

    Trent, Jonathan D (Inventor); Gormly, Sherwin J (Inventor); Embaye, Tsegereda N (Inventor); Delzeit, Lance D (Inventor); Flynn, Michael T (Inventor); Liggett, Travis A (Inventor); Buckwalter, Patrick W (Inventor); Baertsch, Robert (Inventor)

    2013-01-01

    Methods for producing hydrocarbons, including oil, by processing algae and/or other micro-organisms in an aquatic environment. Flexible bags (e.g., plastic) with CO.sub.2/O.sub.2 exchange membranes, suspended at a controllable depth in a first liquid (e.g., seawater), receive a second liquid (e.g., liquid effluent from a "dead zone") containing seeds for algae growth. The algae are cultivated and harvested in the bags, after most of the second liquid is removed by forward osmosis through liquid exchange membranes. The algae are removed and processed, and the bags are cleaned and reused.

  20. Acetone, butanol, and ethanol production from wastewater algae.

    PubMed

    Ellis, Joshua T; Hengge, Neal N; Sims, Ronald C; Miller, Charles D

    2012-05-01

    Acetone, butanol, and ethanol (ABE) fermentation by Clostridium saccharoperbutylacetonicum N1-4 using wastewater algae biomass as a carbon source was demonstrated. Algae from the Logan City Wastewater Lagoon system grow naturally at high rates providing an abundant source of renewable algal biomass. Batch fermentations were performed with 10% algae as feedstock. Fermentation of acid/base pretreated algae produced 2.74 g/L of total ABE, as compared with 7.27 g/L from pretreated algae supplemented with 1% glucose. Additionally, 9.74 g/L of total ABE was produced when xylanase and cellulase enzymes were supplemented to the pretreated algae media. The 1% glucose supplement increased total ABE production approximately 160%, while supplementing with enzymes resulted in a 250% increase in total ABE production when compared to production from pretreated algae with no supplementation of extraneous sugar and enzymes. Additionally, supplementation of enzymes produced the highest total ABE production yield of 0.311 g/g and volumetric productivity of 0.102 g/Lh. The use of non-pretreated algae produced 0.73 g/L of total ABE. The ability to engineer novel methods to produce these high value products from an abundant and renewable feedstock such as algae could have significant implications in stimulating domestic energy economies.

  1. Exploring the potential of using algae in cosmetics.

    PubMed

    Wang, Hui-Min David; Chen, Ching-Chun; Huynh, Pauline; Chang, Jo-Shu

    2015-05-01

    The applications of microalgae in cosmetic products have recently received more attention in the treatment of skin problems, such as aging, tanning and pigment disorders. There are also potential uses in the areas of anti-aging, skin-whitening, and pigmentation reduction products. While algae species have already been used in some cosmetic formulations, such as moisturizing and thickening agents, algae remain largely untapped as an asset in this industry due to an apparent lack of utility as a primary active ingredient. This review article focuses on integrating studies on algae pertinent to skin health and beauty, with the purpose of identifying serviceable algae functions in practical cosmetic uses.

  2. A technical evaluation of biodiesel from vegetable oils vs. algae. Will algae-derived biodiesel perform?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel, one of the most prominent renewable alternative fuels, can be derived from a variety of sources including vegetable oils, animal fats and used cooking oils as well as alternative sources such as algae. While issues such as land-use change, food vs. fuel, feedstock availability, and produc...

  3. Effect of petroleum hydrocarbons on algae

    SciTech Connect

    Bhadauria, S. ); Sengar, R.M.S. ); Mittal, S.; Bhattacharjee, S. )

    1992-01-01

    Algal species (65) were isolated from oil refinery effluent. Twenty-five of these species were cultured in Benecke's medium in a growth chamber, along with controls. Retardation in algal growth, inhibition in algal photosynthesis, and discoloration was observed in petroleum enriched medium. Few forms, viz. Cyclotella sp., Cosmarium sp., and Merismopedia sp. could not survive. The lag phase lengthened by several days and slope of exponential phase was also depressed. Chlamydomonas sp., Scenedesmus sp., Ankistrodesmus sp., Nitzschia sp. and Navicula sp. were comparatively susceptible to petroleum. Depression in carbon fixation, cell numbers, and total dry algal mass was noticeable, showing toxicity to both diatoms and green algae.

  4. Biodiesel from algae: challenges and prospects.

    PubMed

    Scott, Stuart A; Davey, Matthew P; Dennis, John S; Horst, Irmtraud; Howe, Christopher J; Lea-Smith, David J; Smith, Alison G

    2010-06-01

    Microalgae offer great potential for exploitation, including the production of biodiesel, but the process is still some way from being carbon neutral or commercially viable. Part of the problem is that there is little established background knowledge in the area. We should look both to achieve incremental steps and to increase our fundamental understanding of algae to identify potential paradigm shifts. In doing this, integration of biology and engineering will be essential. In this review we present an overview of a potential algal biofuel pipeline, and focus on recent work that tackles optimization of algal biomass production and the content of fuel molecules within the algal cell.

  5. Factors affecting spore germination in algae - review.

    PubMed

    Agrawal, S C

    2009-01-01

    This review surveys whatever little is known on the influence of different environmental factors like light, temperature, nutrients, chemicals (such as plant hormones, vitamins, etc.), pH of the medium, biotic factors (such as algal extracellular substances, algal concentration, bacterial extracellular products, animal grazing and animal extracellular products), water movement, water stress, antibiotics, UV light, X-rays, gamma-rays, and pollution on the spore germination in algae. The work done on the dormancy of algal spores and on the role of vegetative cells in tolerating environmental stress is also incorporated.

  6. Habitat choice by juvenile cod ( Gadus morhua L.) on sandy soft bottoms with different vegetation types

    NASA Astrophysics Data System (ADS)

    Borg, Å.; Pihl, L.; Wennhage, H.

    1997-08-01

    Habitat choice by juvenile cod ( Gadus morhua L.) on sandy bottoms with different vegetation types was studied in laboratory. The experiment was conducted day and night in flow-through tanks on two different size-classes of cod (7-13 and 17-28 cm TL). Four habitats, typical of shallow soft bottoms on the Swedish west coast: Fucus vesiculosus, Zostera marina, Cladophora sp. and bare sand, were set up pair-wise in six combinations. The main difference between habitats in this study was vegetation structure, since all parameters except vegetation type was considered equal for both sides of the experimental tanks and natural prey was eliminated. The results showed a difference in habitat utilization by juvenile cod between day (light) and night (dark). During day time the fishes showed a significant preference for vegetation, while nocturnally no significant choice of habitat was made. Both size-classes preferred Fucus, considered the most complex habitat in this study, when this was available. The smaller size-class seemed to be able to utilize the other vegetation types as well, always preferring vegetation over sand. Larger juvenile cod, on the other hand, appeared to be restricted to Fucus. This difference in habitat choice by the two size-classes might be due to a greater dependence on shelter from predation by the smaller juveniles, causing them to associate more strongly with vegetation. The larger juveniles avoided Cladophora, since they might have difficulties in entering the compact structure of this filamentous algae. Availability of vegetation at day time, as a predation refuge, as well as of open sandy areas for feeding during night, thus seems to be important for juvenile cod. It is concluded that eutrophication-induced changes in habitat structure, such as increased dominance by filamentous algae, could alter the availability of predation refuges and foraging habitats for juvenile cod.

  7. Algae Biofuels Co-Location Assessment Tool

    SciTech Connect

    2013-09-18

    ABCLAT was built to help any model user with spatially explicit Nitrogen, Phosphorous, and Carbon Dioxide nutrient flux information, and solar resource information evaluate algal cultivation potential. Initial applications of this modeling framework include Algae Biofuels Co-Location Assessment Tool Canada and Australia. The Canadian application was copyrighted November 29th 2011 as the Algae Biofuels Co-Location Assessment Tool for Canada. This copyright assertion is for the general framework from which any country or region with the requisite data could create a regionally specific application. The ABCLAT model framework developed by SNL looks at the growth potential in a given region as a function of available nutrients from wastewater and other sources, carbon dioxide from power plants, available solar potential, and if available, land cover and use information. The model framework evaluates the biomass potential, fixed carbon dioxide, potential algal biocrude and required land area for nutrient sources. ABCLAT is built with an object-oriented software program that can provide an easy to use interface for exploring questions related to aigal biomass production.

  8. Algae-based oral recombinant vaccines.

    PubMed

    Specht, Elizabeth A; Mayfield, Stephen P

    2014-01-01

    Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for "molecular pharming" in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae could be poised to become the next candidate in recombinant subunit vaccine production, as they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered - from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and systemic immune reactivity.

  9. Respiratory Chain of Colorless Algae II. Cyanophyta

    PubMed Central

    Webster, D. A.; Hackett, D. P.

    1966-01-01

    Whole cell difference spectra of the blue-green algae, Saprospira grandis, Leucothrix mucor, and Vitreoscilla sp. have one, or at the most 2, broad α-bands near 560 mμ. At −190° these bands split to give 4 peaks in the α-region for b and c-type cytochromes, but no α-band for a-type cytochromes is visible. The NADH oxidase activity of these organisms was shown to be associated with particulate fractions of cell homogenates. The response of this activity to inhibitors differed from the responses of the NADH oxidase activities of particulate preparations from the green algae and higher plants to the same inhibitors, but is more typical of certain bacteria. No cytochrome oxidase activity was present in these preparations. The respiration of Saprospira and Vitreoscilla can be light-reversibly inhibited by CO, and all 3 organisms have a CO-binding pigment whose CO complex absorbs near 570, 535, and 417 mμ. The action spectrum for the light reversal of CO-inhibited Vitreoscilla respiration shows maxima at 568, 534, and 416 mμ. The results suggest that the terminal oxidase in these blue-greens is an o-type cytochrome. Images PMID:5932404

  10. Energy from algae using microbial fuel cells.

    PubMed

    Velasquez-Orta, Sharon B; Curtis, Tom P; Logan, Bruce E

    2009-08-15

    Bioelectricity production from a phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73 +/- 1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m(2) (277 W/m(3)) using C. vulgaris, and 0.76 W/m(2) (215 W/m(3)) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs.

  11. Viruses and viruslike particles of eukaryotic algae.

    PubMed Central

    Van Etten, J L; Lane, L C; Meints, R H

    1991-01-01

    Until recently there was little interest or information on viruses and viruslike particles of eukaryotic algae. However, this situation is changing. In the past decade many large double-stranded DNA-containing viruses that infect two culturable, unicellular, eukaryotic green algae have been discovered. These viruses can be produced in large quantities, assayed by plaque formation, and analyzed by standard bacteriophage techniques. The viruses are structurally similar to animal iridoviruses, their genomes are similar to but larger (greater than 300 kbp) than that of poxviruses, and their infection process resembles that of bacteriophages. Some of the viruses have DNAs with low levels of methylated bases, whereas others have DNAs with high concentrations of 5-methylcytosine and N6-methyladenine. Virus-encoded DNA methyltransferases are associated with the methylation and are accompanied by virus-encoded DNA site-specific (restriction) endonucleases. Some of these enzymes have sequence specificities identical to those of known bacterial enzymes, and others have previously unrecognized specificities. A separate rod-shaped RNA-containing algal virus has structural and nucleotide sequence affinities to higher plant viruses. Quite recently, viruses have been associated with rapid changes in marine algal populations. In the next decade we envision the discovery of new algal viruses, clarification of their role in various ecosystems, discovery of commercially useful genes in these viruses, and exploitation of algal virus genetic elements in plant and algal biotechnology. Images PMID:1779928

  12. Comments on the Manuscript, "Biodiesel Production from Freshwater Algae"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent publication (Vijayaragahavan, K.; Hemanathan, K., Biodiesel from freshwater algae, Energy Fuels, 2009, 23(11):5448-5453) on fuel production from algae is evaluated. It is discussed herein that the fuel discussed in that paper is not biodiesel, rather it probably consists of hydrocarbons. ...

  13. Algae Farming in Low Earth Orbit: Past Present and Future

    NASA Astrophysics Data System (ADS)

    Morrison, N.

    Algal strains used as a production engine represent a novel example of living mechanical systems with tremendous potential for applications in space. Algae use photosynthesis to create lipids, glycerin, and biomass, with different strains of algae producing different oils. Algae can be grown to produce many types of oils, with low, medium or long hydrocarbon chain lengths. This article examines the history of algae research, as well as its value to astronauts as both a food supplement and as an oxygen production and carbon sequester engine. Consideration is given to ways algae is currently being used and tested in space, followed by a look forward envisioning dynamic living technological systems that can help to sustain our race as we travel the void between stars.

  14. Mitigating ammonia nitrogen deficiency in dairy wastewaters for algae cultivation.

    PubMed

    Lu, Qian; Zhou, Wenguang; Min, Min; Ma, Xiaochen; Ma, Yiwei; Chen, Paul; Zheng, Hongli; Doan, Yen T T; Liu, Hui; Chen, Chi; Urriola, Pedro E; Shurson, Gerald C; Ruan, Roger

    2016-02-01

    This study demonstrated that the limiting factor to algae growth on dairy wastewater was the ammonia nitrogen deficiency. Dairy wastewaters were mixed with a slaughterhouse wastewater that has much higher ammonia nitrogen content. The results showed the mixing wastewaters improved the nutrient profiles and biomass yield at low cost. Algae grown on mixed wastewaters contained high protein (55.98-66.91%) and oil content (19.10-20.81%) and can be exploited to produce animal feed and biofuel. Furthermore, algae grown on mixed wastewater significantly reduced nutrient contents remained in the wastewater after treatment. By mitigating limiting factor to algae growth on dairy wastewaters, the key issue of low biomass yield of algae grown on dairy wastewaters was resolved and the wastewater nutrient removal efficiency was significantly improved by this study.

  15. Cryoalgotox: Use of cryopreserved alga in a semistatic microplate test

    SciTech Connect

    Benhra, A.; Radetski, C.M.; Ferard, J.F.

    1997-03-01

    Use of cryopreserved alga Selenastrum capricornutum has been evaluated as a simple and cost-efficient procedure in a new semistatic algal ecotoxicity test. Experiments have been conducted to compare performance criteria of this method, named Cryoalgotox, versus the classic microplate test using fresh algae. Cryoalgotox 72-h 50% effective concentrations (EC50s) determined with Cd{sup 2+}, Cu{sup 2+}, Cr{sup 6+}, and atrazine were more sensitive, repeatable (low coefficients of variation), and reproducible (low time effect) than the results obtained with the classical microplate tests. The effect of storage time at {minus}80 C on the sensitivity of the algae was assessed using cadmium as a toxic reference; it was shown that algae stored at {minus}80 C over a 3-month period gave comparable toxicity results to those found with fresh algae.

  16. Sustainability of algae derived biodiesel: a mass balance approach.

    PubMed

    Pfromm, Peter H; Amanor-Boadu, Vincent; Nelson, Richard

    2011-01-01

    A rigorous chemical engineering mass balance/unit operations approach is applied here to bio-diesel from algae mass culture. An equivalent of 50,000,000 gallons per year (0.006002 m3/s) of petroleum-based Number 2 fuel oil (US, diesel for compression-ignition engines, about 0.1% of annual US consumption) from oleaginous algae is the target. Methyl algaeate and ethyl algaeate diesel can according to this analysis conceptually be produced largely in a technologically sustainable way albeit at a lower available diesel yield. About 11 square miles of algae ponds would be needed with optimistic assumptions of 50 g biomass yield per day and m2 pond area. CO2 to foster algae growth should be supplied from a sustainable source such as a biomass-based ethanol production. Reliance on fossil-based CO2 from power plants or fertilizer production renders algae diesel non-sustainable in the long term.

  17. [Marine algae of Baja California Sur, Mexico: nutritional value].

    PubMed

    Carrillo Domínguez, Silvia; Casas Valdez, Margarita; Ramos Ramos, Felipe; Pérez-Gil, Fernando; Sánchez Rodríguez, Ignacio

    2002-12-01

    The Baja California Peninsula is one of the richest regions of seaweed resources in México. The objective of this study was to determine the chemical composition of some marine algae species of Baja California Sur, with an economical potential due to their abundance and distribution, and to promote their use as food for human consumption and animal feeding. The algae studied were Green (Ulva spp., Enteromorpha intestinalis, Caulerpa sertularoides, Bryopsis hypnoides), Red (Laurencia johnstonii, Spyridia filamentosa, Hypnea valentiae) and Brown (Sargassum herporizum, S. sinicola, Padina durvillaei, Hydroclathrus clathrathus, Colpomenia sinuosa). The algae were dried and ground before analysis. In general, the results showed that algae had a protein level less than 11%, except L. johnstonii with 18% and low energy content. The ether extract content was lower than 1%. However, the algae were a good source of carbohydrates and inorganic matter.

  18. Experimental Evaluation of Seaweeds as a Vector for Microplastics into Marine Food Webs.

    PubMed

    Gutow, Lars; Eckerlebe, Antonia; Giménez, Luis; Saborowski, Reinhard

    2016-01-19

    The ingestion of microplastics has been shown for a great variety of marine organisms. However, benthic marine mesoherbivores such as the common periwinkle Littorina littorea have been largely disregarded in studies about the effects of microplastics on the marine biota, probably because the pathway for microplastics to this functional group of organisms was not obvious. In laboratory experiments we showed that the seaweed Fucus vesiculosus retains suspended microplastics on its surface. The numbers of microplastics that adhered to the algae correlated with the concentrations of suspended particles in the water. In choice feeding assays L. littorea did not distinguish between algae with adherent microplastics and clean algae without microplastics, indicating that the snails do not recognize solid nonfood particles in the submillimeter size range as deleterious. In periwinkles that were feeding on contaminated algae, microplastics were found in the stomach and in the gut. However, no microplastics were found in the midgut gland, which is the principle digestive organ of gastropods. Microplastics in the fecal pellets of the periwinkles indicate that the particles do not accumulate rapidly inside the animals but are mostly released with the feces. Our results provide the first evidence that seaweeds may represent an efficient pathway for microplastics from the water to marine benthic herbivores.

  19. An evaluation of the toxicity and bioaccumulation of bismuth in the coastal environment using three species of macroalga.

    PubMed

    Kearns, James; Turner, Andrew

    2016-01-01

    Bismuth is a heavy metal whose biogeochemical behaviour in the marine environment is poorly defined. In this study, we exposed three different species of macroalga (the chlorophyte, Ulva lactuca, the phaeophyte, Fucus vesiculosus, and the rhodophyte, Chondrus crispus) to different concentrations of Bi (up to 50 μg L(-1)) under controlled, laboratory conditions. After a period of 48-h, the phytotoxicity of Bi was measured in terms of chlorophyll fluorescence quenching, and adsorption and internalisation of Bi determined by ICP after EDTA extraction and acid digestion, respectively. For all algae, both the internalisation and total accumulation of Bi were proportional to the concentration of aqueous metal. Total accumulation followed the order: F. vesiculosus > C. crispus > U. lactuca; with respective accumulation factors of about 4200, 1700 and 600 L kg(-1). Greatest internalisation (about 33% of total accumulated Bi) was exhibited by C. crispus, the only macroalga to display a phytotoxic response in the exposures. A comparison of the present results with those reported in the literature suggests that Bi accumulation by macroalgae is significantly lower than its accumulation by marine plankton (volume concentration factors of 10(5) to 10(7)), and that the phytotoxicity of Bi is low relative to other heavy metals like Ag and Tl.

  20. Fucose-containing sulfated polysaccharides from brown seaweeds inhibit proliferation of melanoma cells and induce apoptosis by activation of caspase-3 in vitro.

    PubMed

    Ale, Marcel Tutor; Maruyama, Hiroko; Tamauchi, Hidekazu; Mikkelsen, Jørn D; Meyer, Anne S

    2011-12-01

    Fucose-containing sulfated polysaccharides (FCSPs) extracted from seaweeds, especially brown macro-algae, are known to possess essential bioactive properties, notably growth inhibitory effects on tumor cells. In this work, we conducted a series of in vitro studies to examine the influence of FCSPs products from Sargassumhenslowianum C. Agardh (FSAR) and Fucus vesiculosus (FVES), respectively, on proliferation of melanoma B16 cells and to investigate the underlying apoptosis promoting mechanisms. Cell viability analysis showed that both FCSPs products, i.e., FSAR and FVES, decreased the proliferation of the melanoma cells in a dose-response fashion, with FSAR being more potent at lower dosages, and FVES being relatively more anti-proliferative than FSAR at higher dosages. Flow cytometric analysis by Annexin V staining of the melanoma cells exposed to the FCSPs products confirmed that both FSAR and FVES induced apoptosis. The FCSPs-induced apoptosis was evidenced by loss of plasma membrane asymmetry and translocation of the cell membrane phospholipids and was accompanied by the activation of caspase-3. The FCSPs bioactivity is proposed to be attributable to distinct structural features of the FCSPs, particularly the presence of sulfated galactofucans (notably in S.henslowianum) and sulfated fucans (notably in F. vesiculosus). This study thus indicates that unfractionated FCSPs may exert bioactive effects on skin cancer cells via induction of apoptosis through cascades of reactions that involve activation of caspase-3.

  1. Castaways can't be choosers - Homogenization of rafting assemblages on floating seaweeds

    NASA Astrophysics Data System (ADS)

    Gutow, Lars; Beermann, Jan; Buschbaum, Christian; Rivadeneira, Marcelo M.; Thiel, Martin

    2015-01-01

    After detachment from benthic habitats, the epibiont assemblages on floating seaweeds undergo substantial changes, but little is known regarding whether succession varies among different seaweed species. Given that floating algae may represent a limiting habitat in many regions, rafting organisms may be unselective and colonize any available seaweed patch at the sea surface. This process may homogenize rafting assemblages on different seaweed species, which our study examined by comparing the assemblages on benthic and floating individuals of the fucoid seaweeds Fucus vesiculosus and Sargassum muticum in the northern Wadden Sea (North Sea). Species richness was about twice as high on S. muticum as on F. vesiculosus, both on benthic and floating individuals. In both seaweed species benthic samples were more diverse than floating samples. However, the species composition differed significantly only between benthic thalli, but not between floating thalli of the two seaweed species. Separate analyses of sessile and mobile epibionts showed that the homogenization of rafting assemblages was mainly caused by mobile species. Among these, grazing isopods from the genus Idotea reached extraordinarily high densities on the floating samples from the northern Wadden Sea, suggesting that the availability of seaweed rafts was indeed limiting. Enhanced break-up of algal rafts associated with intense feeding by abundant herbivores might force rafters to recolonize benthic habitats. These colonization processes may enhance successful dispersal of rafting organisms and thereby contribute to population connectivity between sink populations in the Wadden Sea and source populations from up-current regions.

  2. Reduction of water and energy requirement of algae cultivation using an algae biofilm photobioreactor.

    PubMed

    Ozkan, Altan; Kinney, Kerry; Katz, Lynn; Berberoglu, Halil

    2012-06-01

    This paper reports the construction and performance of an algae biofilm photobioreactor that offers a significant reduction of the energy and water requirements of cultivation. The green alga Botryococcus braunii was cultivated as a biofilm. The system achieved a direct biomass harvest concentration of 96.4 kg/m(3) with a total lipid content 26.8% by dry weight and a productivity of 0.71 g/m(2) day, representing a light to biomass energy conversion efficiency of 2.02%. Moreover, it reduced the volume of water required to cultivate a kilogram of algal biomass by 45% and reduced the dewatering energy requirement by 99.7% compared to open ponds. Finally, the net energy ratio of the cultivation was 6.00 including dewatering. The current issues of this novel photobioreactor are also identified to further improve the system productivity and scaleup.

  3. Phycobiliproteins: A Novel Green Tool from Marine Origin Blue-Green Algae and Red Algae.

    PubMed

    Chandra, Rashmi; Parra, Roberto; Iqbal, Hafiz M N

    2017-01-01

    Marine species are comprising about a half of the whole global biodiversity; the sea offers an enormous resource for novel bioactive compounds. Several of the marine origin species show multifunctional bioactivities and characteristics that are useful for a discovery and/or reinvention of biologically active compounds. For millennia, marine species that includes cyanobacteria (blue-green algae) and red algae have been targeted to explore their enormous potential candidature status along with a wider spectrum of novel applications in bio- and non-bio sectors of the modern world. Among them, cyanobacteria are photosynthetic prokaryotes, phylogenetically a primitive group of Gramnegative prokaryotes, ranging from Arctic to Antarctic regions, capable of carrying out photosynthesis and nitrogen fixation. In the recent decade, a great deal of research attention has been paid on the pronouncement of bio-functional proteins along with novel peptides, vitamins, fine chemicals, renewable fuel and bioactive compounds, e.g., phycobiliproteins from marine species, cyanobacteria and red algae. Interestingly, they are extensively commercialized for natural colorants in food and cosmetics, antimicrobial, antioxidant, anti-inflammatory, neuroprotective, hepatoprotective agents and fluorescent neo-glycoproteins as probes for single particle fluorescence imaging fluorescent applications in clinical and immunological analysis. However, a comprehensive knowledge and technological base for augmenting their commercial utilities are lacking. Therefore, this paper will provide an overview of the phycobiliproteins-based research literature from marine cyanobacteria and red algae. This review is also focused towards analyzing global and commercial activities with application oriented-based research. Towards the end, the information is also given on the potential biotechnological and biomedical applications of phycobiliproteins.

  4. Adaptive traits are maintained on steep selective gradients despite gene flow and hybridization in the intertidal zone.

    PubMed

    Zardi, Gerardo I; Nicastro, Katy R; Canovas, Fernando; Costa, Joana Ferreira; Serrão, Ester A; Pearson, Gareth A

    2011-01-01

    Gene flow among hybridizing species with incomplete reproductive barriers blurs species boundaries, while selection under heterogeneous local ecological conditions or along strong gradients may counteract this tendency. Congeneric, externally-fertilizing fucoid brown algae occur as distinct morphotypes along intertidal exposure gradients despite gene flow. Combining analyses of genetic and phenotypic traits, we investigate the potential for physiological resilience to emersion stressors to act as an isolating mechanism in the face of gene flow. Along vertical exposure gradients in the intertidal zone of Northern Portugal and Northwest France, the mid-low shore species Fucus vesiculosus, the upper shore species Fucus spiralis, and an intermediate distinctive morphotype of F. spiralis var. platycarpus were morphologically characterized. Two diagnostic microsatellite loci recovered 3 genetic clusters consistent with prior morphological assignment. Phylogenetic analysis based on single nucleotide polymorphisms in 14 protein coding regions unambiguously resolved 3 clades; sympatric F. vesiculosus, F. spiralis, and the allopatric (in southern Iberia) population of F. spiralis var. platycarpus. In contrast, the sympatric F. spiralis var. platycarpus (from Northern Portugal) was distributed across the 3 clades, strongly suggesting hybridization/introgression with both other entities. Common garden experiments showed that physiological resilience following exposure to desiccation/heat stress differed significantly between the 3 sympatric genetic taxa; consistent with their respective vertical distribution on steep environmental clines in exposure time. Phylogenetic analyses indicate that F. spiralis var. platycarpus is a distinct entity in allopatry, but that extensive gene flow occurs with both higher and lower shore species in sympatry. Experimental results suggest that strong selection on physiological traits across steep intertidal exposure gradients acts to maintain

  5. Random flow induced by swimming algae

    NASA Astrophysics Data System (ADS)

    Kantsler, Vasily; Rushkin, Ilia; Goldstein, Raymond

    2010-11-01

    In this work we studied the random flow induced in a fluid by the motion of a dilute suspension of the swimming algae Volvox carteri. The fluid velocity in the suspension is a superposition of the flow fields set up by the individual organisms, which in turn have multipole contributions that decay as inverse powers of distance from the organism. Here we show that the conditions under which the central limit theorem guarantees a Gaussian probability distribution function of velocity fluctuations are satisfied when the leading force singularity is a Stokeslet. Deviations from Gaussianity are shown to arise from near-field effects. Comparison is made with the statistical properties of abiotic sedimenting suspensions. The experimental results are supplemented by extensive numerical studies.

  6. Swimming like algae: biomimetic soft artificial cilia.

    PubMed

    Sareh, Sina; Rossiter, Jonathan; Conn, Andrew; Drescher, Knut; Goldstein, Raymond

    2013-01-06

    Cilia are used effectively in a wide variety of biological systems from fluid transport to thrust generation. Here, we present the design and implementation of artificial cilia, based on a biomimetic planar actuator using soft-smart materials. This actuator is modelled on the cilia movement of the alga Volvox, and represents the cilium as a piecewise constant-curvature robotic actuator that enables the subsequent direct translation of natural articulation into a multi-segment ionic polymer metal composite actuator. It is demonstrated how the combination of optimal segmentation pattern and biologically derived per-segment driving signals reproduce natural ciliary motion. The amenability of the artificial cilia to scaling is also demonstrated through the comparison of the Reynolds number achieved with that of natural cilia.

  7. An algae-covered alligator rests warily

    NASA Technical Reports Server (NTRS)

    2000-01-01

    An algae-covered alligator keeps a wary eye open as it rests in one of the ponds at Kennedy Space Center. American alligators feed and rest in the water, and lay their eggs in dens they dig into the banks. The young alligators spend their first several weeks in these dens. The Center shares a boundary with the Merritt Island National Wildlife Refuge, which encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  8. Interactions of metals and protons with algae

    SciTech Connect

    Crist, R.H.; Oberholser, K.; Schwartz, D.; Marzoff, J.; Ryder, D.; Crist, D.R.

    1988-07-01

    Proton uptake by intact algal cells was found to consist of two processes: (1) a fast (<4 s) surface reaction and (2) a slow (2h) diffusion of protons into cells. A pH titration technique measured only the rapid surface reaction that forms negative sites at higher pH. Adsorption of alkali, alkaline earth, and transition metal ions on algae was quantitatively represented by the Langmuir adsorption isotherm with its two parameters y/sub m/, the maximum amount of metal adsorbed, and K, the equilibrium constant taken as a measure of bond strength. Variations of these parameters with pH and type of metal indicate that metals adsorb to algal surfaces by electrostatic attraction to negative sites, such as carboxylate anions of poly(galaturonic acid) (pectin), as previously suggested.

  9. High-fidelity phototaxis in biflagellate algae

    NASA Astrophysics Data System (ADS)

    Leptos, Kyriacos; Chioccioli, Maurizio; Furlan, Silvano; Pesci, Adriana; Goldstein, Raymond

    2015-11-01

    The single-cell alga Chlamydomonas reinhardtii is a motile biflagellate that can swim towards light for its photosynthetic requirements, a behavior referred to as phototaxis. The cell responds upon light stimulation through its rudimentary eye - the eyespot - by changing the beating amplitude of its two flagella accordingly - a process called the photoresponse. All this occurs in a coordinated fashion as Chlamydomonas spins about its body axis while swimming, thus experiencing oscillating intensities of light. We use high-speed video microscopy to measure the flagellar dynamics of the photoresponse on immobilized cells and interpret the results with a mathematical model of adaptation similar to that used previously for Volvox. These results are incorporated into a model of phototactic steering to yield trajectories that are compared to those obtained by three-dimensional tracking. Implications of these results for the evolution of multicellularity in the Volvocales are discussed.

  10. The globins of cyanobacteria and algae.

    PubMed

    Johnson, Eric A; Lecomte, Juliette T J

    2013-01-01

    Approximately, 20 years ago, a haemoglobin gene was identified within the genome of the cyanobacterium Nostoc commune. Haemoglobins have now been confirmed in multiple species of photosynthetic microbes beyond N. commune, and the diversity of these proteins has recently come under increased scrutiny. This chapter summarizes the state of knowledge concerning the phylogeny, physiology and chemistry of globins in cyanobacteria and green algae. Sequence information is by far the best developed and the most rapidly expanding aspect of the field. Structural and ligand-binding properties have been described for just a few proteins. Physiological data are available for even fewer. Although activities such as nitric oxide dioxygenation and oxygen scavenging are strong candidates for cellular function, dedicated studies will be required to complete the story on this intriguing and ancient group of proteins.

  11. Chloroplast Phylogenomic Inference of Green Algae Relationships.

    PubMed

    Sun, Linhua; Fang, Ling; Zhang, Zhenhua; Chang, Xin; Penny, David; Zhong, Bojian

    2016-02-05

    The green algal phylum Chlorophyta has six diverse classes, but the phylogenetic relationship of the classes within Chlorophyta remains uncertain. In order to better understand the ancient Chlorophyta evolution, we have applied a site pattern sorting method to study compositional heterogeneity and the model fit in the green algal chloroplast genomic data. We show that the fastest-evolving sites are significantly correlated with among-site compositional heterogeneity, and these sites have a much poorer fit to the evolutionary model. Our phylogenomic analyses suggest that the class Chlorophyceae is a monophyletic group, and the classes Ulvophyceae, Trebouxiophyceae and Prasinophyceae are non-monophyletic groups. Our proposed phylogenetic tree of Chlorophyta will offer new insights to investigate ancient green algae evolution, and our analytical framework will provide a useful approach for evaluating and mitigating the potential errors of phylogenomic inferences.

  12. Gas Exchange with Mass Cultures of Algae

    PubMed Central

    Hannan, P. J.; Patouillet, Constance

    1963-01-01

    Comparisons of oxygen production and carbon dioxide absorption by an algal gas exchanger were made over a 3-month period. The data do not represent a continuous test, but they do represent results obtained when identical light intensities, CO2 supply rates, and dilution rates with fresh culture medium had been used for more than 1 day. Steady-state conditions were thus assured, and the agreement in the data was excellent. Under the same experimental conditions, the unit was operated continuously for a 5-day period, and the daily variability in this test was less than in the results obtained from month to month. The variation between the average O2 production during the 5-day test and the average of the tests over a several-month period was less than 3%. It is concluded, therefore, that the reliability of the algae in producing oxygen is sufficient to warrant their use in either submarine or space ship use. PMID:14063790

  13. Algae biomass cultivation in nitrogen rich biogas digestate.

    PubMed

    Krustok, I; Diaz, J G; Odlare, M; Nehrenheim, E

    2015-01-01

    Because microalgae are known for quick biomass growth and nutrient uptake, there has been much interest in their use in research on wastewater treatment methods. While many studies have concentrated on the algal treatment of wastewaters with low to medium ammonium concentrations, there are several liquid waste streams with high ammonium concentrations that microalgae could potentially treat. The aim of this paper was to test ammonium tolerance of the indigenous algae community of Lake Mälaren and to use this mixed consortia of algae to remove nutrients from biogas digestate. Algae from Lake Mälaren were cultivated in Jaworski's Medium containing a range of ammonium concentrations and the resulting algal growth was determined. The algae were able to grow at NH4-N concentrations of up to 200 mg L(-1) after which there was significant inhibition. To test the effectiveness of the lake water algae on the treatment of biogas digestate, different pre-cultivation set-ups and biogas digestate concentrations were tested. It was determined that mixing pre-cultivated suspension algae with 25% of biogas digestate by volume, resulting in an ammonium concentration of around 300 mg L(-1), produced the highest algal growth. The algae were effective in removing 72.8±2.2% of NH4-N and 41.4±41.4% of PO4-P.

  14. Biomass of algae growth on natural water medium.

    PubMed

    Ramaraj, Rameshprabu; Tsai, David Dah-Wei; Chen, Paris Honglay

    2015-01-01

    Algae are the dominant primary producers in aquatic ecosystems. Since algae are highly varied group organisms, which have important functions in ecosystem, and their biomass is an essential biological resource. Currently, algae have been applied increasingly to diverse range of biomass applications. Therefore, this study was aimed to investigate the ecological algae features of microalgal production by natural medium, ecological function by lab scale of the symbiotic reactor which is imitated nature ecosystem, and atmospheric CO2 absorption that was related the algal growth of biomass to understand algae in natural water body better. Consequently, this study took advantages of using the unsupplemented freshwater natural medium to produce microalgae. Algal biomass by direct measurement of total suspended solids (TSS) and volatile suspended solids (VSS) resulted as 0.14g/L and 0.08g/L respectively. The biomass measurements of TSS and VSS are the sensible biomass index for algae production. The laboratory results obtained in the present study proved the production of algae by the natural water medium is potentially feasible.

  15. Isoprenoid biosynthesis in eukaryotic phototrophs: A spotlight on algae

    SciTech Connect

    Lohr M.; Schwender J.; Polle, J. E. W.

    2012-04-01

    Isoprenoids are one of the largest groups of natural compounds and have a variety of important functions in the primary metabolism of land plants and algae. In recent years, our understanding of the numerous facets of isoprenoid metabolism in land plants has been rapidly increasing, while knowledge on the metabolic network of isoprenoids in algae still lags behind. Here, current views on the biochemistry and genetics of the core isoprenoid metabolism in land plants and in the major algal phyla are compared and some of the most pressing open questions are highlighted. Based on the different evolutionary histories of the various groups of eukaryotic phototrophs, we discuss the distribution and regulation of the mevalonate (MVA) and the methylerythritol phosphate (MEP) pathways in land plants and algae and the potential consequences of the loss of the MVA pathway in groups such as the green algae. For the prenyltransferases, serving as gatekeepers to the various branches of terpenoid biosynthesis in land plants and algae, we explore the minimal inventory necessary for the formation of primary isoprenoids and present a preliminary analysis of their occurrence and phylogeny in algae with primary and secondary plastids. The review concludes with some perspectives on genetic engineering of the isoprenoid metabolism in algae.

  16. [Numerical simulation on hydrodynamic character for algae growth].

    PubMed

    Wang, Hua; Pang, Yong

    2008-04-01

    In order to quantificationally study the direct effects of hydrodynamic condition on the growth of algae, the Microcystis aeruginosa was chosen to carry through the disturbance-experiment. By keeping the same value of illumination, temperature and nutrition and changing the rotate speed of oscillator, the growing processes of algae under different disturbance intensities were researched. The hydraulic parameter was presented to amend the formula for the growth of algae. Take Neijiang as an example. A 2-D unsteady model for algae growth was established to forecast the scope of water blooms in Neijiang. It is found that the growth of algae is obviously influenced by hydrodynamic condition, and a condign low velocity is beneficial for its growth while both the quiescence condition and high velocity will restrain its growth rate. After the close of the water gate in Leading Channel, the velocity in Neijiang will be decreased, which accelerated the growth rate of algae, and the area of water blooms will be increased to 2.5 km2 which is about 36.8 percent of the total water surface area of Neijiang. Under the quiescent condition and the improved hydrodynamic condition, the growth rate of algae will be effectively controlled and the area of water blooms will be reduced to 0.78 km2 and 0.18 km2 respectively.

  17. [Seasonal variation characteristics of algae biomass in Chaohu Lake].

    PubMed

    Jiang, Xia; Wang, Shu-Hang; Zhong, Li-Xiang; Jin, Xiang-Can; Sun, Shi-Qun

    2010-09-01

    The biomass and distribution of algae community in Chaohu Lake were investigated in 2008. At the same time, the seasonal variations of algae translocation between the sediment and overlying water were also quantitative studied by self-made "algae up/down trap". Chaohu Lake was dominated by Cyanobacteria all the year, and dominant Cyanobacteria species changed in different seasons. In spring, Anabaena was the dominant species, and Microcystis was the subdominant species; In the whole summer and autumn, the dominant species is Microcystis. Algae biomass increased significantly from May and the maximum appeared in August, was 146.37 mg x m(-3) with Chl-a. The value of algae biomass were 9.75-16.24 mg x kg(-1) in the surface sediments, and the minimum appeared in Summer, then the algae biomass increased gradually with the maximum value in winter. Translocation process between the sediment and the overlying water occurred throughout the study period. The recruitment rates increased at first with the maximum rates in early August, was 0.036 8 mg x (m2 x d) (-1), and then had a downward tendency. However the sedimentation rates increased slowly firstly with the maximum rate in early September, then it decreased sharply, was 0.032 1 mg x (m2 x d)(-1). Multiple stepwise regression showed that temperature was the most significant factor for the algae biomass in Chaohu Lake, Total nitrogen (TN) and Total phosphorus(TP) are sub-important factors.

  18. Activated chemical defenses suppress herbivory on freshwater red algae.

    PubMed

    Goodman, Keri M; Hay, Mark E

    2013-04-01

    The rapid life cycles of freshwater algae are hypothesized to suppress selection for chemical defenses against herbivores, but this notion remains untested. Investigations of chemical defenses are rare for freshwater macrophytes and absent for freshwater red algae. We used crayfish to assess the palatability of five freshwater red algae relative to a palatable green alga and a chemically defended aquatic moss. We then assessed the roles of structural, nutritional, and chemical traits in reducing palatability. Both native and non-native crayfish preferred the green alga Cladophora glomerata to four of the five red algae. Batrachospermum helminthosum, Kumanoa holtonii, and Tuomeya americana employed activated chemical defenses that suppressed feeding by 30-60 % following damage to algal tissues. Paralemanea annulata was defended by its cartilaginous structure, while Boldia erythrosiphon was palatable. Activated defenses are thought to reduce ecological costs by expressing potent defenses only when actually needed; thus, activation might be favored in freshwater red algae whose short-lived gametophytes must grow and reproduce rapidly over a brief growing season. The frequency of activated chemical defenses found here (three of five species) is 3-20× higher than for surveys of marine algae or aquatic vascular plants. If typical for freshwater red algae, this suggests that (1) their chemical defenses may go undetected if chemical activation is not considered and (2) herbivory has been an important selective force in the evolution of freshwater Rhodophyta. Investigations of defenses in freshwater rhodophytes contribute to among-system comparisons and provide insights into the generality of plant-herbivore interactions and their evolution.

  19. Photobiological hydrogen production with switchable photosystem-II designer algae

    DOEpatents

    Lee, James Weifu

    2014-02-18

    A process for enhanced photobiological H.sub.2 production using transgenic alga. The process includes inducing exogenous genes in a transgenic alga by manipulating selected environmental factors. In one embodiment inducing production of an exogenous gene uncouples H.sub.2 production from existing mechanisms that would downregulate H.sub.2 production in the absence of the exogenous gene. In other embodiments inducing an exogenous gene triggers a cascade of metabolic changes that increase H.sub.2 production. In some embodiments the transgenic alga are rendered non-regenerative by inducing exogenous transgenes for proton channel polypeptides that are targeted to specific algal membranes.

  20. Preliminary survey of fungistatic properties of marine algae.

    PubMed

    WELCH, A M

    1962-01-01

    Welch, Ann Marie (U. S. Veterans Administration Hospital, Durham, N. C.). Preliminary survey of fungistatic properties of marine algae. J. Bacteriol. 83:97-99. 1962-Homogenized preparations of 35 marine algae were tested for inhibitory activity against 6 pathogenic or opportunistically pathogenic fungi with saturated filter-paper discs on seeded Sabouraud agar plates; 11 of these preparations produced wide zones of inhibition against 1 or more test organisms, and at least 4 of the 11 are considered to be worthy of further study. The results indicated that further search should be made for antifungal substances from marine algae.

  1. Antibacterial properties of a glycolipid-rich extract and active principle from Nunavik collections of the macroalgae Fucus evanescens C. Agardh (Fucaceae).

    PubMed

    Treyvaud Amiguet, Virginie; Jewell, Linda E; Mao, Halimasadia; Sharma, Manju; Hudson, James B; Durst, Tony; Allard, Marc; Rochefort, Guy; Arnason, John Thor

    2011-09-01

    This study investigated the antibacterial activity of glycolipid-rich extracts of the brown macroalga Fucus evanescens in cell culture. Accessions were collected on the Arctic coast of Ungava Bay, Nunavik, Quebec. The crude ethyl acetate extract of these accessions showed strong antibacterial activity (≥4 log(10) cfu) against Hemophilus influenzae , Legionella pneumophila , Propionibacterium acnes (ATCC and clinical isolate), and Streptococcus pyogenes at 100 µg/mL. This algal extract inhibited by 3 log(10) Clostridium difficile and methicillin-resistant Staphylococcus aureus , whereas Bacillus cereus , Escherichia coli , Klebsiella pneumoniae , and Pseudomonas aeruginosa were not significantly affected. Further investigations of the activity of a glycolipid-rich fraction, extracted with dichloromethane, against Propionibacterium acnes showed an MIC(100) of 50 µg/mL, with an inhibition of more than 99% at only 7.8 µg/mL. The main active compound, a β-d-galactosyl O-linked glycolipid, was synthesized for the bioassay and showed an MIC(100) of 50 µg/mL but lost its activity more quickly with only 50% of inhibition at 12.5 µg/mL. Therefore, the semipurified F. evanescens extract could be a good choice for future research into the development of alternative treatments for acne therapy.

  2. Lab on a chip technologies for algae detection: a review.

    PubMed

    Schaap, Allison; Rohrlack, Thomas; Bellouard, Yves

    2012-08-01

    Over the last few decades, lab on a chip technologies have emerged as powerful tools for high-accuracy diagnosis with minute quantities of liquid and as tools for exploring cell properties in general. In this paper, we present a review of the current status of this technology in the context of algae detection and monitoring. We start with an overview of the detection methods currently used for algae monitoring, followed by a review of lab on a chip devices for algae detection and classification, and then discuss a case study based on our own research activities. We conclude with a discussion on future challenges and motivations for algae-oriented lab on a chip technologies.

  3. [Parameter determination of algae growth based on ecological tank experiment].

    PubMed

    Pang, Yong; Ding, Ling; Gao, Guang

    2005-05-01

    A dynamic simulation experiment of algae in an ecological tank was performed at the Taihu Laboratory for Lake Ecosystem Research. During the experiment, water from Taihu Lake was infused into the ecological tank and samples were taken continually to observe algae growth under varying conditions, such as temperature, sunlight and nutrients. Based on the experiment, an algae growth model, considering nitrogen and phosphorus cycle, was developed by using the advanced PHREEQC model. After that, a detailed calibration and validation of parameters in the model were done on the basis of experimental results. The least square method was used to determine the optimal set of parameters. The calculated values of algae and nutrient concentrations show fairly satisfying fittness with measured data.

  4. Application of synthetic biology in cyanobacteria and algae

    PubMed Central

    Wang, Bo; Wang, Jiangxin; Zhang, Weiwen; Meldrum, Deirdre R.

    2012-01-01

    Cyanobacteria and algae are becoming increasingly attractive cell factories for producing renewable biofuels and chemicals due to their ability to capture solar energy and CO2 and their relatively simple genetic background for genetic manipulation. Increasing research efforts from the synthetic biology approach have been made in recent years to modify cyanobacteria and algae for various biotechnological applications. In this article, we critically review recent progresses in developing genetic tools for characterizing or manipulating cyanobacteria and algae, the applications of genetically modified strains for synthesizing renewable products such as biofuels and chemicals. In addition, the emergent challenges in the development and application of synthetic biology for cyanobacteria and algae are also discussed. PMID:23049529

  5. Evaluation of filamentous green algae as feedstocks for biofuel production.

    PubMed

    Zhang, Wei; Zhao, Yonggang; Cui, Binjie; Wang, Hui; Liu, Tianzhong

    2016-11-01

    Compared with unicellular microalgae, filamentous algae have high resistance to grazer-predation and low-cost recovery in large-scale production. Green algae, as the most diverse group of algae, included numerous filamentous genera and species. In this study, records of filamentous genera and species in green algae were firstly censused and classified. Then, seven filamentous strains subordinated in different genera were cultivated in bubbled-column to investigate their growth rate and energy molecular (lipid and starch) capacity. Four strains including Stigeoclonium sp., Oedogonium nodulosum, Hormidium sp. and Zygnema extenue were screened out due to their robust growth. And they all could accumulate triacylglycerols and starch in their biomass, but with different capacity. After nitrogen starvation, Hormidium sp. and Oedogonium nodulosum respectively exhibited high capacity of lipid (45.38% in dry weight) and starch (46.19% in dry weight) accumulation, which could be of high potential as feedstocks for biodiesel and bioethanol production.

  6. Exploration of the gasification of Spirulina algae in supercritical water.

    PubMed

    Miller, Andrew; Hendry, Doug; Wilkinson, Nikolas; Venkitasamy, Chandrasekar; Jacoby, William

    2012-09-01

    This study presents non-catalytic gasification of Spirulina algae in supercritical water using a plug flow reactor and a mechanism for feeding solid carbon streams into high pressure (>25 MPa) environments. A 2(III)(3-1) factorial experimental design explored the effect of concentration, temperature, and residence time on gasification reactions. A positive displacement pump fed algae slurries into the reactor at a temperature range of 550-600°C, and residence times between 4 and 9s. The results indicate that algae gasify efficiently in supercritical water, highlighting the potential for a high throughput process. Additional experiments determined Arrhenius parameters of Spirulina algae. This study also presents a model of the gasification reaction using the estimated activation energy (108 kJ/mol) and other Arrhenius parameters at plug flow conditions. The maximum rate of gasification under the conditions studied of 53 g/Ls is much higher than previously reported.

  7. CONTROL TECHNOLOGY EXTRACTION OF MERCURY FROM GROUNDWATER IMMOBILIZED ALGAE

    EPA Science Inventory

    Bio-Recovery Systems, Inc. conducted a project under the Emerging Technology portion of the United States Environmental Protection Agency (EPAs) Superfund Innovative Technology Evaluation (SITE) Program to evaluate the ability of immobilized algae to adsorb mercury from contamina...

  8. Bicarbonate produced from carbon capture for algae culture.

    PubMed

    Chi, Zhanyou; O'Fallon, James V; Chen, Shulin

    2011-11-01

    Using captured CO(2) to grow microalgae is limited by the high cost of CO(2) capture and transportation, as well as significant CO(2) loss during algae culture. Moreover, algae grow poorly at night, but CO(2) cannot be temporarily stored until sunrise. To address these challenges, we discuss a process where CO(2) is captured as bicarbonate and used as feedstock for algae culture, and the carbonate regenerated by the culture process is used as an absorbent to capture more CO(2). This process would significantly reduce carbon capture costs because it does not require additional energy for carbonate regeneration. Furthermore, not only would transport of the aqueous bicarbonate solution cost less than for that of compressed CO(2), but using bicarbonate would also provide a superior alternative for CO(2) delivery to an algae culture system.

  9. Harmful algae blooms removal from fresh water with modified vermiculite.

    PubMed

    Miao, Chunguang; Tang, Yi; Zhang, Hong; Wu, Zhengyan; Wang, Xiangqin

    2014-01-01

    Vermiculite and vermiculite modified with hydrochloric acid were investigated to evaluate their flocculation efficiencies in freshwater containing harmful algae blooms (HABs) (Microcystis aeruginosa). Scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, converted fluorescence microscope, plasma-atomic emission spectrometry, and Zetasizer were used to study the flocculation mechanism of modified vermiculite. It was found that the vermiculite modified with hydrochloric acid could coagulate algae cells through charge neutralization, chemical bridging, and netting effect. The experimental results show that the efficiency of flocculation can be notably improved by modified vermiculite. Ninety-eight per cent of algae cells in algae solution could be removed within 10 min after the addition ofmodified vermiculite clay. The method that removal of HABs with modified vermiculite is economical with high efficiency, and more research is needed to assess their ecological impacts before using in practical application.

  10. Colourful Cultures: Classroom Experiments with the Unicellular Alga Haematococcus pluvialis.

    ERIC Educational Resources Information Center

    Delpech, Roger

    2001-01-01

    Describes an investigation into the photosynthetic potential of the different developmental stages of the green unicellular alga Haematococcus pluvialis. Reviews the biotechnological applications of astaxanthin, the red pigment which can be extracted from Haematococcus pluvialis. (Author/MM)

  11. Algae Reefs in Shark Bay, Western Australia, Australia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

  12. Study on algae removal by immobilized biosystem on sponge

    NASA Astrophysics Data System (ADS)

    Pei, Haiyan; Hu, Wenrong

    2006-10-01

    In this study, sponges were used to immobilize domesticated sludge microbes in a limited space, forming an immobilized biosystem capable of algae and microcystins removal. The removal effects on algae, microcystins and UV260 of this biosystem and the mechanism of algae removal were studied. The results showed that active sludge from sewage treatment plants was able to remove algae from a eutrophic lake’s water after 7 d of domestication. The removal efficiency for algae, organic matter and microcystins increased when the domesticated sludge was immobilized on sponges. When the hydraulic retention time (HRT) was 5h, the removal rates of algae, microcystins and UV260 were 90%, 94.17% and 84%, respectively. The immobilized biosystem consisted mostly of bacteria, the Ciliata and Sarcodina protozoans and the Rotifer metazoans. Algal decomposition by zoogloea bacteria and preying by microcreatures were the two main modes of algal removal, which occurred in two steps: first, absorption by the zoogloea; second, decomposition by the zoogloea bacteria and the predacity of the microcreatures.

  13. Development of Green Fuels From Algae - The University of Tulsa

    SciTech Connect

    Crunkleton, Daniel; Price, Geoffrey; Johannes, Tyler; Cremaschi, Selen

    2012-12-03

    The general public has become increasingly aware of the pitfalls encountered with the continued reliance on fossil fuels in the industrialized world. In response, the scientific community is in the process of developing non-fossil fuel technologies that can supply adequate energy while also being environmentally friendly. In this project, we concentrate on green fuels which we define as those capable of being produced from renewable and sustainable resources in a way that is compatible with the current transportation fuel infrastructure. One route to green fuels that has received relatively little attention begins with algae as a feedstock. Algae are a diverse group of aquatic, photosynthetic organisms, generally categorized as either macroalgae (i.e. seaweed) or microalgae. Microalgae constitute a spectacularly diverse group of prokaryotic and eukaryotic unicellular organisms and account for approximately 50% of global organic carbon fixation. The PI's have subdivided the proposed research program into three main research areas, all of which are essential to the development of commercially viable algae fuels compatible with current energy infrastructure. In the fuel development focus, catalytic cracking reactions of algae oils is optimized. In the species development project, genetic engineering is used to create microalgae strains that are capable of high-level hydrocarbon production. For the modeling effort, the construction of multi-scaled models of algae production was prioritized, including integrating small-scale hydrodynamic models of algae production and reactor design and large-scale design optimization models.

  14. Feasibility study of algae-based Carbon Dioxide capture ...

    EPA Pesticide Factsheets

    SUMMARY: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to evaluate the benefits of using algae to reduce CO2 emissions from industrial and small-scale utility power boilers. The operations are being studied for the use of CO2 from flue gas for algae growth along with the production of biofuels and other useful products to prepare a comprehensive characterization of the economic feasibility of using algae to capture CO2. Information is being generated for analyses of the potential for these technologies to advance in the market and assist in meeting environmental goals, as well as to examine their associated environmental implications. Three electric power generation plants (coal and fuel oil fired) equipped to send flue-gas emissions to algae culture at demonstration facilities are being studied. Data and process information are being collected and developed to facilitate feasibility and modeling evaluations of the CO2 to algae technology. An understanding of process requirements to apply this technology to existing industries would go far in advancing carbon capture opportunities. Documenting the successful use of this technology could help bring “low-tech”, low-cost, CO2 to algae, carbon capture to multiple size industries and

  15. An overview of algae biofuel production and potential environmental impact.

    PubMed

    Menetrez, Marc Y

    2012-07-03

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas) and produce products with a wide variety of compositions and uses. These products include lipids, which can be processed into biodiesel; carbohydrates, which can be processed into ethanol; and proteins, which can be used for human and animal consumption. Algae are commonly genetically engineered to allow for advantageous process modification or optimization. However, issues remain regarding human exposure to algae-derived toxins, allergens, and carcinogens from both existing and genetically modified organisms (GMOs), as well as the overall environmental impact of GMOs. A literature review was performed to highlight issues related to the growth and use of algal products for generating biofuels. Human exposure and environmental impact issues are identified and discussed, as well as current research and development activities of academic, commercial, and governmental groups. It is hoped that the ideas contained in this paper will increase environmental awareness of issues surrounding the production of algae and will help the algae industry develop to its full potential.

  16. Feeding preferences of mesograzers on aquacultured Gracilaria and sympatric algae

    PubMed Central

    Cruz-Rivera, Edwin; Friedlander, Michael

    2011-01-01

    While large grazers can often be excluded effectively from algal aquaculture operations, smaller herbivores such as small crustaceans and gastropods may be more difficult to control. The susceptibility of three Gracilaria species to herbivores was evaluated in multiple-choice experiments with the amphipod Ampithoe ramondi and the crab Acanthonyx lunulatus. Both mesograzers are common along the Mediterranean coast of Israel. When given a choice, the amphipod preferred to consume Gracilaria lemaneiformis significantly more than either G. conferta or G. cornea. The crab, however, consumed equivalent amounts of G. lemaneiformis and G. conferta, but did not consume G. cornea. Organic content of these algae, an important feeding cue for some mesograzers, could not account for these differences. We further assessed the susceptibility of a candidate species for aquaculture, G. lemaneiformis, against local algae, including common epiphytes. When given a choice of four algae, amphipods preferred the green alga Ulva lactuca over Jania rubens. However, consumption of U. lactuca was equivalent to those of G. lemaneiformis and Padina pavonica. In contrast, the crab showed a marked and significant preference for G. lemaneiformis above any of the other three algae offered. Our results suggest that G. cornea is more resistant to herbivory from common mesograzers and that, contrary to expectations, mixed cultures or epiphyte growth on G. lemaneiformis cannot reduce damage to this commercially appealing alga if small herbivores are capable of recruiting into culture ponds. Mixed cultures may be beneficial when culturing other Gracilaria species. PMID:22711945

  17. [Study on the sorption of 4-octylphenol by freshwater algae].

    PubMed

    Peng, Zhang-e; Yang, Hai-zhen; Wang, Bei-bei; Deng, Nan-sheng

    2009-12-01

    The sorption of 4-octylphenol (4-OP) by two freshwater algae was investigated. Results showed that the sorption of 4-octylphenol by algae was obvious and quick, where 20% of initial 4-OP (2 mg/L) was accumulated by Chlorella vulgaris (CV) and 46% initial 4-OP (2 mg/L) was accumulated by Anabaena cylindrical (AC) after 5 min incubation. The sorption got equilibrium at 1 h after incubation. Langmuir sorption model was good appropriate type for this sorption. The effect of pH value on CV sorption was obvious than that on AC sorption. The sorption capacity of the biomass of two algae increased with the decrease of pH value. The analyzing of interaction between algae and 4-octylphenol was performed by fluorescence spectrum. Results showed that the algae could weaker the fluorescence spectrum intensity of 4-octylphenol and result in red shift of the maximum absorbance wavelength of mixture solution. Based on the results, it was speculated that algae bound with the contamination could use the near UV region of solar radiation and induced the contamination degradation.

  18. Modelling the effect of fluctuating herbicide concentrations on algae growth.

    PubMed

    Copin, Pierre-Jean; Coutu, Sylvain; Chèvre, Nathalie

    2015-03-01

    Herbicide concentrations fluctuate widely in watercourses after crop applications and rain events. The level of concentrations in pulses can exceed the water chronic quality criteria. In the present study, we proposed modelling the effects of successive pulse exposure on algae. The deterministic model proposed is based on two parameters: (i) the typical growth rate of the algae, obtained by monitoring growth rates of several successive batch cultures in growth media, characterizing both the growth of the control and during the recovery periods; (ii) the growth rate of the algae exposed to pulses, determined from a dose-response curve obtained with a standard toxicity test. We focused on the herbicide isoproturon and on the freshwater alga Scenedesmus vacuolatus, and we validated the model prediction based on effect measured during five sequential pulse exposures in laboratory. The comparison between the laboratory and the modelled effects illustrated that the results yielded were consistent, making the model suitable for effect prediction of the herbicide photosystem II inhibitor isoproturon on the alga S. vacuolatus. More generally, modelling showed that both pulse duration and level of concentration play a crucial role. The application of the model to a real case demonstrated that both the highest peaks and the low peaks with a long duration affect principally the cell density inhibition of the alga S. vacuolatus. It is therefore essential to detect these characteristic pulses when monitoring of herbicide concentrations are conducted in rivers.

  19. Phosphorus-Limited Growth of a Green Alga and a Blue-Green Alga

    PubMed Central

    Lang, Douglas S.; Brown, Edward J.

    1981-01-01

    The phosphorus-limited growth kinetics of the chlorophyte Scenedesmus quadricauda and the cyanophyte Synechococcus Nägeli were studied by using batch and continuous culturing techniques. The steady-state phosphate transport capability and the phosphorus storage capacity is higher in S. Nägeli than in S. quadricauda. Synechococcus Nägeli can also deplete phosphate to much lower levels than can S. quadricauda. These results, along with their morphological characteristics, were used to construct partial physiological profiles for each organism. The profiles indicate that this unicellular cyanophyte (cyanobacterium) is better suited for growth in phosphorus-limited oligotrophic niches than is this chlorophyte (green alga). PMID:16345896

  20. Phosphorus-limited growth of a green alga and a blue-green alga

    SciTech Connect

    Lang, D.S.; Brown, E.J.

    1981-12-01

    The phosphorus-limited growth kinetics of the chlorophyte Scenedesmus quadricauda and the cyanophyte Synechococcus Nageli were studied by using batch and continuous culturing techniques. The steady-state phosphate transport capability and the phosphorus storage capacity is higher in S. Nageli than in S. quadricauda. Synechococcus Nageli can also deplete phosphate to much lower levels than can S. quadricauda. These results, along with their morphological characteristics, were used to construct partial physiological profiles for each organism. The profiles indicate that this unicellular cyanophyte (cyanobacterium) is better suited for growth in phosphorus-limited oligotrophic niches than is this chlorophyte (green alga). (Refs. 44).

  1. Is the Future Really in Algae?

    NASA Technical Reports Server (NTRS)

    Trent, Jonathan

    2011-01-01

    Having just emerged from the warmest decade on record and watching as the oceans acidify, global resources peak, the world's population continues to climb, and nearly half of all known species face extinction by the end of the century. We stand on the threshold of one of the most important transition in human history-the transition from hunting-and-gathering our energy to cultivating sustainable, carbon-neutral, environmentally-friendly energy supplies. Can we "cultivate" enerm without competing with agriculture for land, freshwater, or fertilizer? Can we develop an "ecology of technology" that optimizes our use of limited resources? Is human activity compatible with improved conditions in the world's oceans? Will our ingenuity prevail in time to make a difference for our children and the children of all species? With support from NASA ARMD and the California Energy Commission, a group of dedicated scientists and engineers are working on a project called OMEGA (Offshore Membrane Enclosures for Growing Algae), to provide practical answers to these critical questions and to leave a legacy of hope for the oceans and for the future.

  2. Coccolithophorid algae culture in closed photobioreactors.

    PubMed

    Moheimani, Navid R; Isdepsky, Andreas; Lisec, Jan; Raes, Eric; Borowitzka, Michael A

    2011-09-01

    The feasibility of growth, calcium carbonate and lipid production of the coccolithophorid algae (Prymnesiophyceae), Pleurochrysis carterae, Emiliania huxleyi, and Gephyrocapsa oceanica, was investigated in plate, carboy, airlift, and tubular photobioreactors. The plate photobioreactor was the most promising closed cultivation system. All species could be grown in the carboy photobioreactor. However, P. carterae was the only species which grew in an airlift photobioreactor. Despite several attempts to grow these coccolithophorid species in the tubular photobioreactor (Biocoil), including modification of the airlift and sparger design, no net growth could be achieved. The shear produced by turbulence and bubble effects are the most likely reasons for this failure to grow in the Biocoil. The highest total dry weight, lipid and calcium carbonate productivities achieved by P. carterae in the plate photobioreactors were 0.54, 0.12, and 0.06 g L(-1) day(-1) respectively. Irrespective of the type of photobioreactor, the productivities were P. carterae > E. huxleyi > G. oceanica. Pleurochrysis carterae lipid (20-25% of dry weight) and calcium carbonate (11-12% of dry weight) contents were also the highest of all species tested.

  3. Comparative Transcriptome Analysis of Four Prymnesiophyte Algae

    PubMed Central

    Koid, Amy E.; Liu, Zhenfeng; Terrado, Ramon; Jones, Adriane C.; Caron, David A.; Heidelberg, Karla B.

    2014-01-01

    Genomic studies of bacteria, archaea and viruses have provided insights into the microbial world by unveiling potential functional capabilities and molecular pathways. However, the rate of discovery has been slower among microbial eukaryotes, whose genomes are larger and more complex. Transcriptomic approaches provide a cost-effective alternative for examining genetic potential and physiological responses of microbial eukaryotes to environmental stimuli. In this study, we generated and compared the transcriptomes of four globally-distributed, bloom-forming prymnesiophyte algae: Prymnesium parvum, Chrysochromulina brevifilum, Chrysochromulina ericina and Phaeocystis antarctica. Our results revealed that the four transcriptomes possess a set of core genes that are similar in number and shared across all four organisms. The functional classifications of these core genes using the euKaryotic Orthologous Genes (KOG) database were also similar among the four study organisms. More broadly, when the frequencies of different cellular and physiological functions were compared with other protists, the species clustered by both phylogeny and nutritional modes. Thus, these clustering patterns provide insight into genomic factors relating to both evolutionary relationships as well as trophic ecology. This paper provides a novel comparative analysis of the transcriptomes of ecologically important and closely related prymnesiophyte protists and advances an emerging field of study that uses transcriptomics to reveal ecology and function in protists. PMID:24926657

  4. Detection of Cyanotoxins in Algae Dietary Supplements

    PubMed Central

    Roy-Lachapelle, Audrey; Solliec, Morgan; Bouchard, Maryse F.; Sauvé, Sébastien

    2017-01-01

    Algae dietary supplements are marketed worldwide as natural health products. Although their proprieties have been claimed as beneficial to improve overall health, there have been several previous reports of contamination by cyanotoxins. These products generally contain non-toxic cyanobacteria, but the methods of cultivation in natural waters without appropriate quality controls allow contamination by toxin producer species present in the natural environment. In this study, we investigated the presence of total microcystins, seven individual microcystins (RR, YR, LR, LA, LY, LW, LF), anatoxin-a, dihydroanatoxin-a, epoxyanatoxin-a, cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine in 18 different commercially available products containing Spirulina or Aphanizomenon flos-aquae. Total microcystins analysis was accomplished using a Lemieux oxidation and a chemical derivatization using dansyl chloride was needed for the simultaneous analysis of cylindrospermopsin, saxitoxin, and β-methylamino-l-alanine. Moreover, the use of laser diode thermal desorption (LDTD) and ultra-high performance liquid chromatography (UHPLC) both coupled to high resolution mass spectrometry (HRMS) enabled high performance detection and quantitation. Out of the 18 products analyzed, 8 contained some cyanotoxins at levels exceeding the tolerable daily intake values. The presence of cyanotoxins in these algal dietary supplements reinforces the need for a better quality control as well as consumer’s awareness on the potential risks associated with the consumption of these supplements. PMID:28245621

  5. Properties of polysaccharides in several seaweeds from Atlantic Canada and their potential anti-influenza viral activities

    NASA Astrophysics Data System (ADS)

    Jiao, Guangling; Yu, Guangli; Wang, Wei; Zhao, Xiaoliang; Zhang, Junzeng; Ewart, Stephen H.

    2012-06-01

    To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae ( Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae ( Ascophyllum nodosum and Fucus vesiculosus), and one green alga ( Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were analyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.

  6. Two-step evolution of endosymbiosis between hydra and algae.

    PubMed

    Ishikawa, Masakazu; Shimizu, Hiroshi; Nozawa, Masafumi; Ikeo, Kazuho; Gojobori, Takashi

    2016-10-01

    In the Hydra vulgaris group, only 2 of the 25 strains in the collection of the National Institute of Genetics in Japan currently show endosymbiosis with green algae. However, whether the other non-symbiotic strains also have the potential to harbor algae remains unknown. The endosymbiotic potential of non-symbiotic strains that can harbor algae may have been acquired before or during divergence of the strains. With the aim of understanding the evolutionary process of endosymbiosis in the H. vulgaris group, we examined the endosymbiotic potential of non-symbiotic strains of the H. vulgaris group by artificially introducing endosymbiotic algae. We found that 12 of the 23 non-symbiotic strains were able to harbor the algae until reaching the grand-offspring through the asexual reproduction by budding. Moreover, a phylogenetic analysis of mitochondrial genome sequences showed that all the strains with endosymbiotic potential grouped into a single cluster (cluster γ). This cluster contained two strains (J7 and J10) that currently harbor algae; however, these strains were not the closest relatives. These results suggest that evolution of endosymbiosis occurred in two steps; first, endosymbiotic potential was gained once in the ancestor of the cluster γ lineage; second, strains J7 and J10 obtained algae independently after the divergence of the strains. By demonstrating the evolution of the endosymbiotic potential in non-symbiotic H. vulgaris group strains, we have clearly distinguished two evolutionary steps. The step-by-step evolutionary process provides significant insight into the evolution of endosymbiosis in cnidarians.

  7. Plasticity predicts evolution in a marine alga.

    PubMed

    Schaum, C Elisa; Collins, Sinéad

    2014-10-22

    Under global change, populations have four possible responses: 'migrate, acclimate, adapt or die' (Gienapp et al. 2008 Climate change and evolution: disentangling environmental and genetic response. Mol. Ecol. 17, 167-178. (doi:10.1111/j.1365-294X.2007.03413.x)). The challenge is to predict how much migration, acclimatization or adaptation populations are capable of. We have previously shown that populations from more variable environments are more plastic (Schaum et al. 2013 Variation in plastic responses of a globally distributed picoplankton species to ocean acidification. Nature 3, 298-230. (doi:10.1038/nclimate1774)), and here we use experimental evolution with a marine microbe to learn that plastic responses predict the extent of adaptation in the face of elevated partial pressure of CO2 (pCO2). Specifically, plastic populations evolve more, and plastic responses in traits other than growth can predict changes in growth in a marine microbe. The relationship between plasticity and evolution is strongest when populations evolve in fluctuating environments, which favour the evolution and maintenance of plasticity. Strikingly, plasticity predicts the extent, but not direction of phenotypic evolution. The plastic response to elevated pCO2 in green algae is to increase cell division rates, but the evolutionary response here is to decrease cell division rates over 400 generations until cells are dividing at the same rate their ancestors did in ambient CO2. Slow-growing cells have higher mitochondrial potential and withstand further environmental change better than faster growing cells. Based on this, we hypothesize that slow growth is adaptive under CO2 enrichment when associated with the production of higher quality daughter cells.

  8. Plasticity predicts evolution in a marine alga

    PubMed Central

    Schaum, C. Elisa; Collins, Sinéad

    2014-01-01

    Under global change, populations have four possible responses: ‘migrate, acclimate, adapt or die’ (Gienapp et al. 2008 Climate change and evolution: disentangling environmental and genetic response. Mol. Ecol. 17, 167–178. (doi:10.1111/j.1365-294X.2007.03413.x)). The challenge is to predict how much migration, acclimatization or adaptation populations are capable of. We have previously shown that populations from more variable environments are more plastic (Schaum et al. 2013 Variation in plastic responses of a globally distributed picoplankton species to ocean acidification. Nature 3, 298–230. (doi:10.1038/nclimate1774)), and here we use experimental evolution with a marine microbe to learn that plastic responses predict the extent of adaptation in the face of elevated partial pressure of CO2 (pCO2). Specifically, plastic populations evolve more, and plastic responses in traits other than growth can predict changes in growth in a marine microbe. The relationship between plasticity and evolution is strongest when populations evolve in fluctuating environments, which favour the evolution and maintenance of plasticity. Strikingly, plasticity predicts the extent, but not direction of phenotypic evolution. The plastic response to elevated pCO2 in green algae is to increase cell division rates, but the evolutionary response here is to decrease cell division rates over 400 generations until cells are dividing at the same rate their ancestors did in ambient CO2. Slow-growing cells have higher mitochondrial potential and withstand further environmental change better than faster growing cells. Based on this, we hypothesize that slow growth is adaptive under CO2 enrichment when associated with the production of higher quality daughter cells. PMID:25209938

  9. Method and apparatus using an active ionic liquid for algae biofuel harvest and extraction

    SciTech Connect

    Salvo, Roberto Di; Reich, Alton; Dykes, Jr., H. Waite H.; Teixeira, Rodrigo

    2012-11-06

    The invention relates to use of an active ionic liquid to dissolve algae cell walls. The ionic liquid is used to, in an energy efficient manner, dissolve and/or lyse an algae cell walls, which releases algae constituents used in the creation of energy, fuel, and/or cosmetic components. The ionic liquids include ionic salts having multiple charge centers, low, very low, and ultra low melting point ionic liquids, and combinations of ionic liquids. An algae treatment system is described, which processes wet algae in a lysing reactor, separates out algae constituent products, and optionally recovers the ionic liquid in an energy efficient manner.

  10. Anti-Phytopathogenic Activities of Macro-Algae Extracts

    PubMed Central

    Jiménez, Edra; Dorta, Fernando; Medina, Cristian; Ramírez, Alberto; Ramírez, Ingrid; Peña-Cortés, Hugo

    2011-01-01

    Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens. PMID:21673886

  11. Evolution of reproductive development in the volvocine algae.

    PubMed

    Hallmann, Armin

    2011-06-01

    The evolution of multicellularity, the separation of germline cells from sterile somatic cells, and the generation of a male-female dichotomy are certainly among the greatest innovations of eukaryotes. Remarkably, phylogenetic analysis suggests that the shift from simple to complex, differentiated multicellularity was not a unique progression in the evolution of life, but in fact a quite frequent event. The spheroidal green alga Volvox and its close relatives, the volvocine algae, span the full range of organizational complexity, from unicellular and colonial genera to multicellular genera with a full germ-soma division of labor and male-female dichotomy; thus, these algae are ideal model organisms for addressing fundamental issues related to the transition to multicellularity and for discovering universal rules that characterize this transition. Of all living species, Volvox carteri represents the simplest version of an immortal germline producing specialized somatic cells. This cellular specialization involved the emergence of mortality and the production of the first dead ancestors in the evolution of this lineage. Volvocine algae therefore exemplify the evolution of cellular cooperation from cellular autonomy. They also serve as a prime example of the evolution of complex traits by a few successive, small steps. Thus, we learn from volvocine algae that the evolutionary transition to complex, multicellular life is probably much easier to achieve than is commonly believed.

  12. Boron uptake, localization, and speciation in marine brown algae.

    PubMed

    Miller, Eric P; Wu, Youxian; Carrano, Carl J

    2016-02-01

    In contrast to the generally boron-poor terrestrial environment, the concentration of boron in the marine environment is relatively high (0.4 mM) and while there has been extensive interest in its use as a surrogate of pH in paleoclimate studies in the context of climate change-related questions, the relatively depth independent, and the generally non-nutrient-like concentration profile of this element have led to boron being neglected as a potentially biologically relevant element in the ocean. Among the marine plant-like organisms the brown algae (Phaeophyta) are one of only five lineages of photosynthetic eukaryotes to have evolved complex multicellularity. Many of unusual and often unique features of brown algae are attributable to this singular evolutionary history. These adaptations are a reflection of the marine coastal environment which brown algae dominate in terms of biomass. Consequently, brown algae are of fundamental importance to oceanic ecology, geochemistry, and coastal industry. Our results indicate that boron is taken up by a facilitated diffusion mechanism against a considerable concentration gradient. Furthermore, in both Ectocarpus and Macrocystis some boron is most likely bound to cell wall constituent alginate and the photoassimilate mannitol located in sieve cells. Herein, we describe boron uptake, speciation, localization and possible biological function in two species of brown algae, Macrocystis pyrifera and Ectocarpus siliculosus.

  13. Method to transform algae, materials therefor, and products produced thereby

    DOEpatents

    Dunahay, Terri Goodman; Roessler, Paul G.; Jarvis, Eric E.

    1997-01-01

    Disclosed is a method to transform chlorophyll C-containing algae which includes introducing a recombinant molecule comprising a nucleic acid molecule encoding a dominant selectable marker operatively linked to an algal regulatory control sequence into a chlorophyll C-containing alga in such a manner that the marker is produced by the alga. In a preferred embodiment the algal regulatory control sequence is derived from a diatom and preferably Cyclotella cryptica. Also disclosed is a chimeric molecule having one or more regulatory control sequences derived from one or more chlorophyll C-containing algae operatively linked to a nucleic acid molecule encoding a selectable marker, an RNA molecule and/or a protein, wherein the nucleic acid molecule does not normally occur with one or more of the regulatory control sequences. Further specifically disclosed are molecules pACCNPT10, pACCNPT4.8 and pACCNPT5.1. The methods and materials of the present invention provide the ability to accomplish stable genetic transformation of chlorophyll C-containing algae.

  14. Method to transform algae, materials therefor, and products produced thereby

    DOEpatents

    Dunahay, T.G.; Roessler, P.G.; Jarvis, E.E.

    1997-08-26

    Disclosed is a method to transform chlorophyll C-containing algae. The method includes introducing a recombinant molecule comprising a nucleic acid molecule encoding a dominant selectable marker operatively linked to an algal regulatory control sequence into a chlorophyll C-containing alga in such a manner that the marker is produced by the alga. In a preferred embodiment the algal regulatory control sequence is derived from a diatom and preferably Cyclotella cryptica. Also disclosed is a chimeric molecule having one or more regulatory control sequences derived from one or more chlorophyll C-containing algae operatively linked to a nucleic acid molecule encoding a selectable marker, an RNA molecule and/or a protein, wherein the nucleic acid molecule does not normally occur with one or more of the regulatory control sequences. Further, specifically disclosed are molecules pACCNPT10, pACCNPT4.8 and pACCNPT5.1. The methods and materials of the present invention provide the ability to accomplish stable genetic transformation of chlorophyll C-containing algae. 2 figs.

  15. Algae-bacteria interactions: Evolution, ecology and emerging applications.

    PubMed

    Ramanan, Rishiram; Kim, Byung-Hyuk; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2016-01-01

    Algae and bacteria have coexisted ever since the early stages of evolution. This coevolution has revolutionized life on earth in many aspects. Algae and bacteria together influence ecosystems as varied as deep seas to lichens and represent all conceivable modes of interactions - from mutualism to parasitism. Several studies have shown that algae and bacteria synergistically affect each other's physiology and metabolism, a classic case being algae-roseobacter interaction. These interactions are ubiquitous and define the primary productivity in most ecosystems. In recent years, algae have received much attention for industrial exploitation but their interaction with bacteria is often considered a contamination during commercialization. A few recent studies have shown that bacteria not only enhance algal growth but also help in flocculation, both essential processes in algal biotechnology. Hence, there is a need to understand these interactions from an evolutionary and ecological standpoint, and integrate this understanding for industrial use. Here we reflect on the diversity of such relationships and their associated mechanisms, as well as the habitats that they mutually influence. This review also outlines the role of these interactions in key evolutionary events such as endosymbiosis, besides their ecological role in biogeochemical cycles. Finally, we focus on extending such studies on algal-bacterial interactions to various environmental and bio-technological applications.

  16. Development and characteristics of an adhesion bioassay for ectocarpoid algae.

    PubMed

    Evariste, Emmanuelle; Gachon, Claire M M; Callow, Maureen E; Callow, James A

    2012-01-01

    Species of filamentous brown algae in the family Ectocarpaceae are significant members of fouling communities. However, there are few systematic studies on the influence of surface physico-chemical properties on their adhesion. In the present paper the development of a novel, laboratory-based adhesion bioassay for ectocarpoid algae, at an appropriate scale for the screening of sets of experimental samples in well-replicated and controlled experiments is described. The assays are based on the colonization of surfaces from a starting inoculum consisting of multicellular filaments obtained by blending the cultured alga Ectocarpus crouaniorum. The adhesion strength of the biomass after 14 days growth was assessed by applying a hydrodynamic shear stress. Results from adhesion tests on a set of standard surfaces showed that E. crouaniorum adhered more weakly to the amphiphilic Intersleek® 900 than to the more hydrophobic Intersleek® 700 and Silastic® T2 coatings. Adhesion to hydrophilic glass was also weak. Similar results were obtained for other cultivated species of Ectocarpus but differed from those obtained with the related ectocarpoid species Hincksia secunda. The response of the ectocarpoid algae to the surfaces was also compared to that for the green alga, Ulva.

  17. Application of algae-biosensor for environmental monitoring.

    PubMed

    Umar, Lazuardi; Alexander, Frank A; Wiest, Joachim

    2015-01-01

    Environmental problems including water and air pollution, over fertilization, insufficient wastewater treatment and even ecological disaster are receiving greater attention in the technical and scientific area. In this paper, a method for water quality monitoring using living green algae (Chlorella Kessleri) with the help of the intelligent mobile lab (IMOLA) is presented. This measurement used two IMOLA systems for measurement and reference simultaneously to verify changes due to pollution inside the measurement system. The IMOLA includes light emitting diodes to stimulate photosynthesis of the living algae immobilized on a biochip containing a dissolved oxygen microsensor. A fluid system is used to transport algae culture medium in a stop and go mode; 600s ON, 300s OFF, while the oxygen concentration of the water probe is measured. When the pump stops, the increase in dissolved oxygen concentration due to photosynthesis is detected. In case of a pollutant being transported toward the algae, this can be detected by monitoring the photosynthetic activity. Monitoring pollution is shown by adding emulsion of 0,5mL of Indonesian crude palm oil and 10mL algae medium to the water probe in the biosensor.

  18. Visualization of oxygen distribution patterns caused by coral and algae.

    PubMed

    Haas, Andreas F; Gregg, Allison K; Smith, Jennifer E; Abieri, Maria L; Hatay, Mark; Rohwer, Forest

    2013-01-01

    Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were assessed in light and dark conditions and under varying flow regimes. The images show discrete high oxygen concentration regions above the organisms during lighted periods and low oxygen in the dark. Size and orientation of these areas were dependent on flow regime. For corals and algae in close proximity the 2D optodes show areas of extremely low oxygen concentration at the interaction interfaces under both dark (18.4 ± 7.7 µmol O2 L(- 1)) and daylight (97.9 ± 27.5 µmol O2 L(- 1)) conditions. These images present the first two-dimensional visualization of oxygen gradients generated by benthic reef algae and corals under varying flow conditions and provide a 2D depiction of previously observed hypoxic zones at coral algae interfaces. This approach allows for visualization of locally confined, distinctive alterations of oxygen concentrations facilitated by benthic organisms and provides compelling evidence for hypoxic conditions at coral-algae interaction zones.

  19. Designer proton-channel transgenic algae for photobiological hydrogen production

    DOEpatents

    Lee, James Weifu [Knoxville, TN

    2011-04-26

    A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

  20. [Nutritive value of the spirulina algae (Spirulina maxima)].

    PubMed

    Tejada de Hernández, I; Shimada, A S

    1978-06-01

    Nine experiments were conducted, five of them in vivo to determine the limiting amino acids and digestibility of spiruline algae for the rat, and four in vitro to determine the digestibility of the product in pepsin and ruminal liquid. None of the amino acids studied (lysine, methionine, histidine) added alone or in combination to 10% protein (either crude or true) diets provided exclusively by spiruline, seems to be limiting although the results could be masked by the low palatability and acceptability of the product by the rats. The apparent digestibility of the algae was 67.4%. For the in vitro tests, the algae were subjected to several physical or chemical treatments, and the digestibility of the resulting product determined by four different techniques. In no case did the tested treatments have any effect on its digestibility.

  1. Algae from the arid southwestern United States: an annotated bibliography

    SciTech Connect

    Thomas, W.H.; Gaines, S.R.

    1983-06-01

    Desert algae are attractive biomass producers for capturing solar energy through photosynthesis of organic matter. They are probably capable of higher yields and efficiencies of light utilization than higher plants, and are already adapted to extremes of sunlight intensity, salinity and temperature such as are found in the desert. This report consists of an annotated bibliography of the literature on algae from the arid southwestern United States. It was prepared in anticipation of efforts to isolate desert algae and study their yields in the laboratory. These steps are necessary prior to setting up outdoor algal culture ponds. Desert areas are attractive for such applications because land, sunlight, and, to some extent, water resources are abundant there. References are sorted by state.

  2. Importance of algae as a potential source of biofuel.

    PubMed

    Singh, A K; Singh, M P

    2014-12-24

    Algae have a great potential source of biofuels and also have unique importance to reduce gaseous emissions, greenhouse gases, climatic changes, global warming receding of glaciers, rising sea levels and loss of biodiversity. The microalgae, like Scenedesmus obliquus, Neochloris oleabundans, Nannochloropsis sp., Chlorella emersonii, and Dunaliella tertiolecta have high oil content. Among the known algae, Scenedesmus obliquus is one of the most potential sources for biodiesel as it has adequate fatty acid (linolenic acid) and other polyunsaturated fatty acids. Bio—ethanol is already in the market of United States of America and Europe as an additive in gasoline. Bio—hydrogen is the cleanest biofuel and extensive efforts are going on to bring it to market at economical price. This review highlights recent development and progress in the field of algae as a potential source of biofuel.

  3. An updated comprehensive techno-economic analysis of algae biodiesel.

    PubMed

    Nagarajan, Sanjay; Chou, Siaw Kiang; Cao, Shenyan; Wu, Chen; Zhou, Zhi

    2013-10-01

    Algae biodiesel is a promising but expensive alternative fuel to petro-diesel. To overcome cost barriers, detailed cost analyses are needed. A decade-old cost analysis by the U.S. National Renewable Energy Laboratory indicated that the costs of algae biodiesel were in the range of $0.53-0.85/L (2012 USD values). However, the cost of land and transesterification were just roughly estimated. In this study, an updated comprehensive techno-economic analysis was conducted with optimized processes and improved cost estimations. Latest process improvement, quotes from vendors, government databases, and other relevant data sources were used to calculate the updated algal biodiesel costs, and the final costs of biodiesel are in the range of $0.42-0.97/L. Additional improvements on cost-effective biodiesel production around the globe to cultivate algae was also recommended. Overall, the calculated costs seem promising, suggesting that a single step biodiesel production process is close to commercial reality.

  4. Potential anti-inflammatory natural products from marine algae.

    PubMed

    Fernando, I P Shanura; Nah, Jae-Woon; Jeon, You-Jin

    2016-12-01

    Inflammatory diseases have become one of the leading causes of health issue throughout the world, having a considerable influence on healthcare costs. With the emerging developments in natural product, synthetic and combinatorial chemistry, a notable success has been achieved in discovering natural products and their synthetic structural analogs with anti-inflammatory activity. However, many of these therapeutics have indicated detrimental side effects upon prolonged usage. Marine algae have been identified as an underexplored reservoir of unique anti-inflammatory compounds. These include polyphenols, sulfated polysaccharides, terpenes, fatty acids, proteins and several other bioactives. Consumption of these marine algae could provide defense against the pathophysiology of many chronic inflammatory diseases. With further investigation, algal anti-inflammatory phytochemicals have the potential to be used as therapeutics or in the synthesis of structural analogs with profound anti-inflammatory activity with reduced side effects. The current review summarizes the latest knowledge about the potential anti-inflammatory compounds discovered from marine algae.

  5. Benefits of using algae as natural sources of functional ingredients.

    PubMed

    Ibañez, Elena; Cifuentes, Alejandro

    2013-03-15

    Algae have been suggested as a potential source of bioactive compounds to be used in the food and pharmaceutical industries. With the strong development of functional foods as a method to improve or maintain health, the exploration of new compounds with real health effects is now an intense field of research. The potential use of algae as source of functional food ingredients, such as lipids, proteins, polysaccharides, phenolics, carotenoids, etc., is presented, together with the different possibilities of improving valuable metabolites production either using the tools and the knowledge provided by marine biotechnology or improving the different factors involved in the production on a large scale of such metabolites. The bio-refinery concept is also presented as a way to improve the efficient use of algae biomass while favouring process sustainability.

  6. The evolution of photosynthesis in chromist algae through serial endosymbioses

    PubMed Central

    Stiller, John W.; Schreiber, John; Yue, Jipei; Guo, Hui; Ding, Qin; Huang, Jinling

    2014-01-01

    Chromist algae include diverse photosynthetic organisms of great ecological and social importance. Despite vigorous research efforts, a clear understanding of how various chromists acquired photosynthetic organelles has been complicated by conflicting phylogenetic results, along with an undetermined number and pattern of endosymbioses, and the horizontal movement of genes that accompany them. We apply novel statistical approaches to assess impacts of endosymbiotic gene transfer on three principal chromist groups at the heart of long-standing controversies. Our results provide robust support for acquisitions of photosynthesis through serial endosymbioses, beginning with the adoption of a red alga by cryptophytes, then a cryptophyte by the ancestor of ochrophytes, and finally an ochrophyte by the ancestor of haptophytes. Resolution of how chromist algae are related through endosymbioses provides a framework for unravelling the further reticulate history of red algal-derived plastids, and for clarifying evolutionary processes that gave rise to eukaryotic photosynthetic diversity. PMID:25493338

  7. Extremophilic micro-algae and their potential contribution in biotechnology.

    PubMed

    Varshney, Prachi; Mikulic, Paulina; Vonshak, Avigad; Beardall, John; Wangikar, Pramod P

    2015-05-01

    Micro-algae have potential as sustainable sources of energy and products and alternative mode of agriculture. However, their mass cultivation is challenging due to low survival under harsh outdoor conditions and competition from other, undesired, species. Extremophilic micro-algae have a role to play by virtue of their ability to grow under acidic or alkaline pH, high temperature, light, CO2 level and metal concentration. In this review, we provide several examples of potential biotechnological applications of extremophilic micro-algae and the ranges of tolerated extremes. We also discuss the adaptive mechanisms of tolerance to these extremes. Analysis of phylogenetic relationship of the reported extremophiles suggests certain groups of the Kingdom Protista to be more tolerant to extremophilic conditions than other taxa. While extremophilic microalgae are beginning to be explored, much needs to be done in terms of the physiology, molecular biology, metabolic engineering and outdoor cultivation trials before their true potential is realized.

  8. Enhanced lipid extraction from algae using free nitrous acid pretreatment.

    PubMed

    Bai, Xue; Naghdi, Forough Ghasemi; Ye, Liu; Lant, Paul; Pratt, Steven

    2014-05-01

    Lipid extraction has been identified as a major bottleneck for large-scale algal biodiesel production. In this work free nitrous acid (FNA) is presented as an effective and low cost pretreatment to enhance lipid recovery from algae. Two batch tests, with a range of FNA additions, were conducted to disrupt algal cells prior to lipid extraction by organic solvents. Total accessible lipid content was quantified by the Bligh and Dyer method, and was found to increase with pretreatment time (up to 48 h) and FNA concentration (up to 2.19 mg HNO2-N/L). Hexane extraction was used to study industrially accessible lipids. The mass transfer coefficient (k) for lipid extraction using hexane from algae treated with 2.19 mg HNO2-N/L FNA was found to be dramatically higher than for extraction from untreated algae. Consistent with extraction results, cell disruption analysis indicated the disruption of the cell membrane barrier.

  9. [Sedimentary Phosphorus Forms Under Disturbances and Algae in Taihu Lake].

    PubMed

    Chen, Jun; Li, Da-peng; Zhu, Pei-ying; Huang, Yong; Wang, Ren

    2015-12-01

    Sedimentary phosphorus forms were investigated to clarify the release of sedimentary phosphorus forms under the repeated disturbance with the addition of algae at different initial concentrations. The sediments and overlying water were taken from the Meiliang Bay in Taihu Lake. The results showed that the concentrations of NH₄ Cl-P and Res-P decreased, while the content of Fe/Al-P and Ca-P increased without disturbance. In addition, the Ca-P increased with the increase of the initial concentration of algae and the net increase of Ca-P increased by 48% (30 µg · L⁻¹), 66% (60 µg · L⁻¹), 74% (120 µg · L⁻¹), respectively. However, under the disturbance, the NH₄Cl-P and Res-P were significantly reduced, the Fe/Al-P increased significantly. The percentage of Fe/Al-P to Tot-P was up to 66. 2% (average of the 3 experiments with the addition of algae of 30 µg · L⁻¹, 60 µg · L⁻¹ and 120 µg L-¹), it was higher than the value (53.%, average of the 3 experiments) without the disturbance. Moreover, under the disturbance, the percentage of Ca-P to Tot-P was 24.1% (average of the 3 experiments with the addition of algae of 30 µg · L⁻¹, 60 µg⁻¹ and 120 µg · L⁻¹) and it was slightly lower than that (33.0%, average of the 3 experiments) without the disturbance. It is suggested that the coexistence of disturbance and algae facilitated the formation of Fe/Al-P, but the algae accelerated the formation of Ca-P without disturbance.

  10. Aragonitic Pennsylvanian phylloid algae from New Mexico: The missing link

    SciTech Connect

    Kirkland, B.L.; Moore, C.H. Jr. ); Dickson, J.A.D. )

    1991-03-01

    Remarkably well-preserved codiacean algae (Eugonophyllum and Anchicodium) retaining original aragonite are present in the Virgilian Holder Formation, Sacramento Mountains, south-central New Mexico. The algae are preserved in a 20-cm-thick packstone between two thick (> 5m) shale beds. Aragonite is preserved as a felt-like mesh of needles in the algal skeletons, in the shell fragments of molluscs, in the walls of sponges, and in botryoidal and isopachous marine cements. The aragonite is confirmed by X-ray diffraction, by visual inspection of pristine aragonite needles with SEM, and by a high content of Sr as revealed by microprobe analysis. The average Sr content of the algae (9,091 ppm, n = 21) is comparable to modern codiaceans. Preservation of internal structure in Eugonophyllum was previously unknown. The medullary (interior) region of the Eugonophyllum thallus is composed of an aragonite felt punctuated by small (20 {mu}m diameter), parallel utricles. As in modern codiaceans, the utricles in the cortical (exterior) region of the thallus increase in diameter and their bulbous tips coalesce to form the outer cortex of the plant. This occurrence provides a key piece of evidence in support of hypotheses concerning the nature and origin of phylloid algal bioherms. Because the internal structure of most fossil phylloid algae is replaced by sparry mosaic calcite, taxonomic classification has been difficult even at the fundamental level of division (phylum). The authors discovery confirms that at least some ancient phylloid algae resembled the modern green algae Halimeda or Udotea, and lends credibility to the suggestion that ancient phylloid algal mounds are analogous to modern Halimeda mounds of the South Pacific.

  11. Oleosin of subcellular lipid droplets evolved in green algae.

    PubMed

    Huang, Nan-Lan; Huang, Ming-Der; Chen, Tung-Ling L; Huang, Anthony H C

    2013-04-01

    In primitive and higher plants, intracellular storage lipid droplets (LDs) of triacylglycerols are stabilized with a surface layer of phospholipids and oleosin. In chlorophytes (green algae), a protein termed major lipid-droplet protein (MLDP) rather than oleosin on LDs was recently reported. We explored whether MLDP was present directly on algal LDs and whether algae had oleosin genes and oleosins. Immunofluorescence microscopy revealed that MLDP in the chlorophyte Chlamydomonas reinhardtii was associated with endoplasmic reticulum subdomains adjacent to but not directly on LDs. In C. reinhardtii, low levels of a transcript encoding an oleosin-like protein (oleolike) in zygotes-tetrads and a transcript encoding oleosin in vegetative cells transferred to an acetate-enriched medium were found in transcriptomes and by reverse transcription-polymerase chain reaction. The C. reinhardtii LD fraction contained minimal proteins with no detectable oleolike or oleosin. Several charophytes (advanced green algae) possessed low levels of transcripts encoding oleosin but not oleolike. In the charophyte Spirogyra grevilleana, levels of oleosin transcripts increased greatly in cells undergoing conjugation for zygote formation, and the LD fraction from these cells contained minimal proteins, two of which were oleosins identified via proteomics. Because the minimal oleolike and oleosins in algae were difficult to detect, we tested their subcellular locations in Physcomitrella patens transformed with the respective algal genes tagged with a Green Fluorescent Protein gene and localized the algal proteins on P. patens LDs. Overall, oleosin genes having weak and cell/development-specific expression were present in green algae. We present a hypothesis for the evolution of oleosins from algae to plants.

  12. Algae Biofuels Co-Location Assessment Tool for Canada

    SciTech Connect

    2011-11-29

    The Algae Biofuels Co-Location Assessment Tool for Canada uses chemical stoichiometry to estimate Nitrogen, Phosphorous, and Carbon atom availability from waste water and carbon dioxide emissions streams, and requirements for those same elements to produce a unit of algae. This information is then combined to find limiting nutrient information and estimate potential productivity associated with waste water and carbon dioxide sources. Output is visualized in terms of distributions or spatial locations. Distances are calculated between points of interest in the model using the great circle distance equation, and the smallest distances found by an exhaustive search and sort algorithm.

  13. Homogeneity of Danish environmental and clinical isolates of Shewanella algae.

    PubMed

    Vogel, B F; Holt, H M; Gerner-Smidt, P; Bundvad, A; Sogaard, P; Gram, L

    2000-01-01

    Danish isolates of Shewanella algae constituted by whole-cell protein profiling a very homogeneous group, and no clear distinction was seen between strains from the marine environment and strains of clinical origin. Although variation between all strains was observed by ribotyping and random amplified polymorphic DNA analysis, no clonal relationship between infective strains was found. From several patients, clonally identical strains of S. algae were reisolated up to 8 months after the primary isolation, indicating that the same strain may be able to maintain the infection.

  14. Algae as promising organisms for environment and health

    PubMed Central

    2011-01-01

    Algae, like other plants, produce a variety of remarkable compounds collectively referred to as secondary metabolites. They are synthesized by these organisms at the end of the growth phase and/or due to metabolic alterations induced by environmental stress conditions. Carotenoids, phenolic compounds, phycobiliprotein pigments, polysaccharides and unsaturated fatty acids are same of the algal natural products, which were reported to have variable biological activities, including antioxidant activity, anticancer activity, antimicroabial activity against bacteria-virus-algae-fungi, organic fertilizer and bioremediation potentials. PMID:21862867

  15. Heavy metals in marine algae of the Kuwait coast

    SciTech Connect

    Buo-Olayan, A.H.; Subrahmanyam, M.N.V.

    1996-12-31

    Marine algae are considered as important primary producers in the coastal region. Several marine algal species are being considered as raw material for various economically important products and this has resulted in their increasing demand. Marine algal species also have been suggested to be the indicators of pollution. Keeping in view the importance of marine algal species for direct or indirect human and cattle consumption, it is necessary to monitor the bioaccumulation of certain elements in these species. This study was aimed at establishing the concentration levels of trace metals in marine algae of the Kuwait coast. 26 refs., 1 fig., 3 tabs.

  16. Value of crops: Quantity, quality and cost price. [algae as a nutritional supplement

    NASA Technical Reports Server (NTRS)

    Meyer, C.

    1979-01-01

    Possibilities of using algae as a nutritional supplement are examined. The nutritional value and protein content of spirulines of blue algae are discussed. A cost analysis of growing them artificially is presented.

  17. [Effectiveness and characteristics of treating algae-laden raw water by stocking silver carp].

    PubMed

    Fan, Zhen-Qiang; Cui, Fu-Yi; Ma, Hua; He, Wen-Jie; Yin, Pei-Jun

    2008-03-01

    To reduce the negative effect of algae on conventional water treatment, a full-scale research of removing algae from algae-laden raw water by stocking filter-feeding silver carp was processed. After the pretreatment in a presedimentation tank with silver carp, the concentration of phytoplankton, the biomass of cyanobacteria and Microsystis flos-aquae in algae-laden raw water with Microsystis flos-aquae its dominant species decreased 61.8%, 76.1% and 78.2% respectively. This effective decrease of algae load on conventional process created favorable conditions for water treatment. Analysis indicates that food habit of silver carp and algae size are two causes of different removal efficiency between cyanobacteria and green algae. The results show that biomanipulation of silver carp is applicable for treating algae-laden raw water in which colonial cyanobacteria is dominant.

  18. Application of mass spectrometric techniques for the trace analysis of short-lived iodine-containing volatiles emitted by seaweed.

    PubMed

    Kundel, Michael; Thorenz, Ute R; Petersen, Jan H; Huang, Ru-Jin; Bings, Nicolas H; Hoffmann, Thorsten

    2012-04-01

    Knowledge of the composition and emission rates of iodine-containing volatiles from major widespread seaweed species is important for modeling the impact of halogens on gas-phase atmospheric chemistry, new particle formation, and climate. In this work, we present the application of mass spectrometric techniques for the quantification of short-lived iodine-containing volatiles emitted by eight different seaweeds from the intertidal zone of Helgoland, Germany. A previously developed online time-of-flight aerosol mass spectrometric method was used to determine I(2) emission rates and investigate temporally resolved emission profiles. Simultaneously, iodocarbons were preconcentrated on solid adsorbent tubes and quantified offline using thermodesorption-gas chromatography-mass spectrometry. The total iodine content of the seaweeds was determined using microwave-assisted tetramethylammonium hydroxide extraction followed by inductively coupled-plasma mass spectrometry analysis. The highest total iodine content was found in the Laminariales, followed by the brown algae Ascophyllum nodosum, Fucus vesiculosus, Fucus serratus, and both red algae Chondrus crispus and Delesseria sanguinea. Laminariales were found to be the strongest I(2) emitters. Time series of the iodine release of Laminaria digitata and Laminaria hyperborea showed a strong initial I(2) emission when first exposed to air followed by an exponential decline of the release rate. For both species, I(2) emission bursts were observed. For Laminaria saccharina und F. serratus, a more continuous I(2) release profile was detected, however, F. serratus released much less I(2). A. nodosum and F. vesiculosus showed a completely different emission behavior. The I(2) emission rates of these species were slowly increasing with time during the first 1 to 2 h until a more or less stable I(2) emission rate was reached. The lowest I(2) emission rates were detected for the red algae C. crispus and D. sanguinea. Total iodocarbon

  19. Modeling and Control of Algae Harvesting, Dewatering and Drying (HDD) Systems

    DTIC Science & Technology

    2012-05-01

    MODELING AND CONTROL OF ALGAE HARVESTING, DEWATERING AND DRYING (HDD) SYSTEMS by FENGMING LI Submitted in partial fulfillment of the...Modeling and Control of Algae Harvesting, Dewatering and Drying (HDD) Systems 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...ALTERNATIVE ENERGY .................................................................................................................. 3 1.3 ALGAE OIL

  20. Where Have All the Algae Gone, or, How Many Kingdoms Are There?

    ERIC Educational Resources Information Center

    Blackwell, Will H.; Powell, Martha J.

    1995-01-01

    Examined 10 introductory college-level, general biology survey textbooks for the coverage of algae to assess the efficacy of coverage. Describes a proposal of seven kingdoms and discusses the disposition of algae among five of these kingdoms. Contends that textbooks should highlight the concept of algae across the five kingdoms. Contains 59…

  1. MONITORING CHLOROPHYLL-A AS A MEASURE OF ALGAE IN LAKE WATER

    EPA Science Inventory

    Algae are an important quality component in water bodies. They are photosynthesizing organisms and are the foundation of most aquatic food webs; however, some algae (e.g. blue-green algae) can produce algal toxins. The presence of algal toxins in water bodies has important ...

  2. Assembly of Photosynthetic Antenna Protein / Pigments Complexes from Algae and Plants for Development of Nanobiodevices

    DTIC Science & Technology

    2012-07-10

    Assembly of Photosynthetic Antenna Protein / Pigments Complexes from Algae and Plants for Development of Nanobiodevices Key...Assembly of Photosynthetic Antenna Protein / Pigments Complexes from Algae and Plants for Development of Nanobiodevices 5a. CONTRACT NUMBER...unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT This is the report of a project to use photosynthetic antenna pigment complexes from algae and plants as

  3. Critical conditions for ferric chloride-induced flocculation of freshwater algae.

    PubMed

    Wyatt, Nicholas B; Gloe, Lindsey M; Brady, Patrick V; Hewson, John C; Grillet, Anne M; Hankins, Matthew G; Pohl, Phillip I

    2012-02-01

    The effects of algae concentration, ferric chloride dose, and pH on the flocculation efficiency of the freshwater algae Chlorella zofingiensis can be understood by considering the nature of the electrostatic charges on the algae and precipitate surfaces. Two critical conditions are identified which, when met, result in flocculation efficiencies in excess of 90% for freshwater algae. First, a minimum concentration of ferric chloride is required to overcome the electrostatic stabilization of the algae and promote bridging of algae cells by hydroxide precipitates. At low algae concentrations, the minimum amount of ferric chloride required increases linearly with algae concentration, characteristic of flocculation primarily through electrostatic bridging by hydroxide precipitates. At higher algae concentrations, the minimum required concentration of ferric chloride for flocculation is independent of algae concentration, suggesting a change in the primary flocculation mechanism from bridging to sweep flocculation. Second, the algae must have a negative surface charge. Experiments and surface complexation modeling show that the surface charge of C. zofingiensis is negative above a pH of 4.0 ± 0.3 which agrees well with the minimum pH required for effective flocculation. These critical flocculation criteria can be extended to other freshwater algae to design effective flocculation systems.

  4. MicroRNAs in a multicellular green alga Volvox carteri.

    PubMed

    Li, Jingrui; Wu, Yang; Qi, Yijun

    2014-01-01

    microRNAs (miRNAs) have emerged as key components in the eukaryotic gene regulatory network. We and others have previously identified many miRNAs in a unicellular green alga, Chlamydomonas reinhardtii. To investigate whether miRNA-mediated gene regulation is a general mechanism in green algae and how miRNAs have been evolved in the green algal lineage, we examined small RNAs in Volvox carteri, a multicellular species in the same family with Chlamydomonas reinhardtii. We identified 174 miRNAs in Volvox, with many of them being highly enriched in gonidia or somatic cells. The targets of the miRNAs were predicted and many of them were subjected to miRNA-mediated cleavage in vivo, suggesting that miRNAs play regulatory roles in the biology of green algae. Our catalog of miRNAs and their targets provides a resource for further studies on the evolution, biological functions, and genomic properties of miRNAs in green algae.

  5. Sexual reproduction and sex determination in green algae.

    PubMed

    Sekimoto, Hiroyuki

    2017-02-10

    The sexual reproductive processes of some representative freshwater green algae are reviewed. Chlamydomonas reinhardtii is a unicellular volvocine alga having two mating types: mating type plus (mt(+)) and mating type minus (mt(-)), which are controlled by a single, complex mating-type locus. Sexual adhesion between the gametes is mediated by sex-specific agglutinin molecules on their flagellar membranes. Cell fusion is initiated by an adhesive interaction between the mt(+) and mt(-) mating structures, followed by localized membrane fusion. The loci of sex-limited genes and the conformation of sex-determining regions have been rearranged during the evolution of volvocine algae; however, the essential function of the sex-determining genes of the isogamous unicellular Chlamydomonas reinhardtii is conserved in the multicellular oogamous Volvox carteri. The sexual reproduction of the unicellular charophycean alga, Closterium peracerosum-strigosum-littorale complex, is also focused on here. The sexual reproductive processes of heterothallic strains are controlled by two multifunctional sex pheromones, PR-IP and PR-IP Inducer, which independently promote multiple steps in conjugation at the appropriate times through different induction mechanisms. The molecules involved in sexual reproduction and sex determination have also been characterized.

  6. Carbon Partitioning in Green Algae (Chlorophyta) and the Enolase Enzyme

    PubMed Central

    Polle, Jürgen E. W.; Neofotis, Peter; Huang, Andy; Chang, William; Sury, Kiran; Wiech, Eliza M.

    2014-01-01

    The exact mechanisms underlying the distribution of fixed carbon within photoautotrophic cells, also referred to as carbon partitioning, and the subcellular localization of many enzymes involved in carbon metabolism are still unknown. In contrast to the majority of investigated green algae, higher plants have multiple isoforms of the glycolytic enolase enzyme, which are differentially regulated in higher plants. Here we report on the number of gene copies coding for the enolase in several genomes of species spanning the major classes of green algae. Our genomic analysis of several green algae revealed the presence of only one gene coding for a glycolytic enolase [EC 4.2.1.11]. Our predicted cytosolic localization would require export of organic carbon from the plastid to provide substrate for the enolase and subsequent re-import of organic carbon back into the plastids. Further, our comparative sequence study of the enolase and its 3D-structure prediction may suggest that the N-terminal extension found in green algal enolases could be involved in regulation of the enolase activity. In summary, we propose that the enolase represents one of the crucial regulatory bottlenecks in carbon partitioning in green algae. PMID:25093929

  7. Fatty acid amides from freshwater green alga Rhizoclonium hieroglyphicum.

    PubMed

    Dembitsky, V M; Shkrob, I; Rozentsvet, O A

    2000-08-01

    Freshwater green algae Rhizoclonium hieroglyphicum growing in the Ural Mountains were examined for their fatty acid amides using capillary gas chromatography-mass spectrometry (GC-MS). Eight fatty acid amides were identified by GC-MS. (Z)-9-octadecenamide was found to be the major component (2.26%).

  8. Switchable photosystem-II designer algae for photobiological hydrogen production

    DOEpatents

    Lee, James Weifu

    2010-01-05

    A switchable photosystem-II designer algae for photobiological hydrogen production. The designer transgenic algae includes at least two transgenes for enhanced photobiological H.sub.2 production wherein a first transgene serves as a genetic switch that can controls photosystem II (PSII) oxygen evolution and a second transgene encodes for creation of free proton channels in the algal photosynthetic membrane. In one embodiment, the algae includes a DNA construct having polymerase chain reaction forward primer (302), a inducible promoter (304), a PSII-iRNA sequence (306), a terminator (308), and a PCR reverse primer (310). In other embodiments, the PSII-iRNA sequence (306) is replaced with a CF.sub.1-iRNA sequence (312), a streptomycin-production gene (314), a targeting sequence (316) followed by a proton-channel producing gene (318), or a PSII-producing gene (320). In one embodiment, a photo-bioreactor and gas-product separation and utilization system produce photobiological H.sub.2 from the switchable PSII designer alga.

  9. Phytotoxicity, bioaccumulation and degradation of isoproturon in green algae.

    PubMed

    Bi, Yan Fang; Miao, Shan Shan; Lu, Yi Chen; Qiu, Chong Bin; Zhou, You; Yang, Hong

    2012-12-01

    Isoproturon (IPU) is a pesticide used for protection of land crops from weed or pathogen attack. Recent survey shows that IPU has been detected as a contaminant in aquatic systems and may have negative impact on aquatic organisms. To understand the phytotoxicity and potential accumulation and degradation of IPU in algae, a comprehensive study was performed with the green alga Chlamydomonas reinhardtii. Algae exposed to 5-50 μg L(-1) IPU for 3d displayed progressive inhibition of cell growth and reduced chlorophyll fluorescence. Time-course experiments with 25 μg L(-1) IPU for 6d showed similar growth responses. The 72 h EC50 value for IPU was 43.25 μg L(-1), NOEC was 5 μg L(-1) and LOEC was 15 μg L(-1). Treatment with IPU induced oxidative stress. This was validated by a group of antioxidant enzymes, whose activities were promoted by IPU exposure. The up-regulation of several genes coding for the enzymes confirmed the observation. IPU was shown to be readily accumulated by C. reinhardtii. However, the alga showed a weak ability to degrade IPU accumulated in its cells, which was best presented at the lower concentration (5 μg L(-1)) of IPU in the medium. The imbalance of accumulation and degradation of IPU may be the cause that resulted in the detrimental growth and cellular damage.

  10. Effect of sonication frequency on the disruption of algae.

    PubMed

    Kurokawa, Masaki; King, Patrick M; Wu, Xiaoge; Joyce, Eadaoin M; Mason, Timothy J; Yamamoto, Ken

    2016-07-01

    In this study, the efficiency of ultrasonic disruption of Chaetoceros gracilis, Chaetoceros calcitrans, and Nannochloropsis sp. was investigated by applying ultrasonic waves of 0.02, 0.4, 1.0, 2.2, 3.3, and 4.3 MHz to algal suspensions. The results showed that reduction in the number of algae was frequency dependent and that the highest efficiency was achieved at 2.2, 3.3, and 4.3MHz for C. gracilis, C. calcitrans, and Nannochloropsis sp., respectively. A review of the literature suggested that cavitation, rather than direct effects of ultrasonication, are required for ultrasonic algae disruption, and that chemical effects are likely not the main mechanism for algal cell disruption. The mechanical resonance frequencies estimated by a shell model, taking into account elastic properties, demonstrated that suitable disruption frequencies for each alga were associated with the cell's mechanical properties. Taken together, we consider here that physical effects of ultrasonication were responsible for algae disruption.

  11. Ecological assessments with algae: a review and synthesis.

    PubMed

    Stevenson, Jan

    2014-06-01

    Algae have been used for a century in environmental assessments of water bodies and are now used in countries around the world. This review synthesizes recent advances in the field around a framework for environmental assessment and management that can guide design of assessments, applications of phycology in assessments, and refinements of those applications to better support management decisions. Algae are critical parts of aquatic ecosystems that power food webs and biogeochemical cycling. Algae are also major sources of problems that threaten many ecosystems goods and services when abundances of nuisance and toxic taxa are high. Thus, algae can be used to indicate ecosystem goods and services, which complements how algal indicators are also used to assess levels of contaminants and habitat alterations (stressors). Understanding environmental managers' use of algal ecology, taxonomy, and physiology can guide our research and improve its application. Environmental assessments involve characterizing ecological condition and diagnosing causes and threats to ecosystems goods and services. Recent advances in characterizing condition include site-specific models that account for natural variability among habitats to better estimate effects of humans. Relationships between algal assemblages and stressors caused by humans help diagnose stressors and establish targets for protection and restoration. Many algal responses to stressors have thresholds that are particularly important for developing stakeholder consensus for stressor management targets. Future research on the regional-scale resilience of algal assemblages, the ecosystem goods and services they provide, and methods for monitoring and forecasting change will improve water resource management.

  12. Lysis of Blue-Green Algae by Myxobacter

    PubMed Central

    Shilo, Miriam

    1970-01-01

    Enrichment from local fishponds led to the isolation of a bacterium capable of lysing many species of unicellular and filamentous blue-green algae, as well as certain bacteria. The isolate is an aflagellate, motile rod which moves in a gliding, flexuous manner; the organism is capable of digesting starch and agar, but not cellulose and gelatin. Its deoxyribonucleic acid base pair composition (per cent guanine plus cytosine ∼70) shows a close resemblance to that of the fruiting myxobacteria. Algae in lawns on agar plates were lysed rapidly by the myxobacter, but only limited and slow lysis occurred in liquid media, and no lysis took place when liquid cultures were shaken. No diffusible lytic factors would be demonstrated. Continuous observation of the lytic process under a phase-contrast microscope suggested that a close contact between the polar tip of the myxobacter and the alga is necessary for lysis. The lytic action is limited to the vegetative cells of the algae, whereas heterocysts are not affected. The gas vacuoles of the algal host are the only remnant visible after completion of digestion by the myxobacter. Images PMID:4990764

  13. Survey of Hydrogenase Activity in Algae: Final Report

    SciTech Connect

    Brand, J. J.

    1982-04-01

    The capacity for hydrogen gas production was examined in nearly 100 strains of Eukaryotic algae. Each strain was assessed for rate of H2 production in darkness, at compensating light intensity and at saturating Tight intensity. Maximum H2 yield on illumination and sensitivity to molecular oxygen were also measured.

  14. Energy-water nexus for mass cultivation of algae.

    PubMed

    Murphy, Cynthia Folsom; Allen, David T

    2011-07-01

    Microalgae are currently considered a potential feedstock for the production of biofuels. This work addresses the energy needed to manage the water used in the mass cultivation of saline, eukaryotic algae grown in open pond systems. Estimates of both direct and upstream energy requirements for obtaining, containing, and circulating water within algae cultivation systems are developed. Potential productivities are calculated for each of the 48 states within the continental U.S. based on theoretical photosynthetic efficiencies, growing season, and total available land area. Energy output in the form of algal biodiesel and the total energy content of algal biomass are compared to energy inputs required for water management. The analysis indicates that, for current technologies, energy required for water management alone is approximately seven times greater than energy output in the form of biodiesel and more than double that contained within the entire algal biomass. While this analysis addresses only currently identified species grown in an open-pond system, the water management requirements of any algae system will be substantial; therefore, it is critical that an energy assessment of water management requirements be performed for any cultivation technology and algal type in order to fully understand the energy balance of algae-derived biofuels.

  15. Optimization of light use efficiency for biofuel production in algae.

    PubMed

    Simionato, Diana; Basso, Stefania; Giacometti, Giorgio M; Morosinotto, Tomas

    2013-12-01

    A major challenge for next decades is development of competitive renewable energy sources, highly needed to compensate fossil fuels reserves and reduce greenhouse gas emissions. Among different possibilities, which are currently under investigation, there is the exploitation of unicellular algae for production of biofuels and biodiesel in particular. Some algae species have the ability of accumulating large amount of lipids within their cells which can be exploited as feedstock for the production of biodiesel. Strong research efforts are however still needed to fulfill this potential and optimize cultivation systems and biomass harvesting. Light provides the energy supporting algae growth and available radiation must be exploited with the highest possible efficiency to optimize productivity and make microalgae large scale cultivation energetically and economically sustainable. Investigation of the molecular bases influencing light use efficiency is thus seminal for the success of this biotechnology. In this work factors influencing light use efficiency in algal biomass production are reviewed, focusing on how algae genetic engineering and control of light environment within photobioreactors can improve the productivity of large scale cultivation systems.

  16. Basis for the Resistance of Several Algae to Microbial Decomposition

    PubMed Central

    Gunnison, Douglas; Alexander, Martin

    1975-01-01

    The basis for the resistance of certain algae to microbial decomposition in natural waters was investigated using Pediastrum duplex, Staurastrum sp., and Fischerella muscicola as test organisms. Enzyme preparations previously found to convert susceptible algae into spheroplasts had no such effect on the resistant species, although glucose and galacturonic acid were released from P. duplex walls. Little protein or lipid but considerable carbohydrate was found in the walls of the refractory organisms, but resistance was not correlated with the presence of a unique sugar monomer. A substance present in Staurastrum sp. walls was characterized as lignin or lignin-like on the basis of its extraction characteristics, infrared spectrum, pyrolysis pattern, and content of an aromatic building block. Sporopollenin was found in P. duplex, and cellulose in Staurastrum sp. Cell walls of the algae were fractionated, and the fractions least susceptible to microbial degradation were the sporopollenin of P. duplex, the polyaromatic component of Staurastrum sp., and two F. muscicola fractions containing several sugar monomers. The sporopollenin content of P. duplex, the content of lignin or a related constituent of Staurastrum sp., and the resistance of the algae to microbial attack increased with age. It is suggested that resistance results from the presence of sporopollenin in P. duplex, a lignin-like material in Staurastrum sp., and possibly heteropolysaccharides in F. muscicola. PMID:808166

  17. Study of ecotoxicity of silver nanoparticles using algae

    NASA Astrophysics Data System (ADS)

    Kustov, L. M.; Abramenko, N. B.

    2016-11-01

    Silver nanoparticles have been prepared and tested for their ecotoxicity using Chlorella vulgaris Beijer. algae as a hydrobiotic test organism and a photometric method of control. The toxicity was supposed to originate from Ag+ ions released into the aqueous solution. Also, the toxicity of the stabilizing agent was found to be comparable to that of silver nanoparticles.

  18. Decreased abundance of crustose coralline algae due to ocean acidification

    USGS Publications Warehouse

    Kuffner, Ilsa B.; Andersson, Andreas J; Jokiel, Paul L.; Rodgers, Ku'ulei S.; Mackenzie, Fred T.

    2008-01-01

    Owing to anthropogenic emissions, atmospheric concentrations of carbon dioxide could almost double between 2006 and 2100 according to business-as-usual carbon dioxide emission scenarios1. Because the ocean absorbs carbon dioxide from the atmosphere2, 3, 4, increasing atmospheric carbon dioxide concentrations will lead to increasing dissolved inorganic carbon and carbon dioxide in surface ocean waters, and hence acidification and lower carbonate saturation states2, 5. As a consequence, it has been suggested that marine calcifying organisms, for example corals, coralline algae, molluscs and foraminifera, will have difficulties producing their skeletons and shells at current rates6, 7, with potentially severe implications for marine ecosystems, including coral reefs6, 8, 9, 10, 11. Here we report a seven-week experiment exploring the effects of ocean acidification on crustose coralline algae, a cosmopolitan group of calcifying algae that is ecologically important in most shallow-water habitats12, 13, 14. Six outdoor mesocosms were continuously supplied with sea water from the adjacent reef and manipulated to simulate conditions of either ambient or elevated seawater carbon dioxide concentrations. The recruitment rate and growth of crustose coralline algae were severely inhibited in the elevated carbon dioxide mesocosms. Our findings suggest that ocean acidification due to human activities could cause significant change to benthic community structure in shallow-warm-water carbonate ecosystems.

  19. Expression and assembly of a fully active antibody in algae

    NASA Astrophysics Data System (ADS)

    Mayfield, Stephen P.; Franklin, Scott E.; Lerner, Richard A.

    2003-01-01

    Although combinatorial antibody libraries have solved the problem of access to large immunological repertoires, efficient production of these complex molecules remains a problem. Here we demonstrate the efficient expression of a unique large single-chain (lsc) antibody in the chloroplast of the unicellular, green alga, Chlamydomonas reinhardtii. We achieved high levels of protein accumulation by synthesizing the lsc gene in chloroplast codon bias and by driving expression of the chimeric gene using either of two C. reinhardtii chloroplast promoters and 5' and 3' RNA elements. This lsc antibody, directed against glycoprotein D of the herpes simplex virus, is produced in a soluble form by the alga and assembles into higher order complexes in vivo. Aside from dimerization by disulfide bond formation, the antibody undergoes no detectable posttranslational modification. We further demonstrate that accumulation of the antibody can be modulated by the specific growth regime used to culture the alga, and by the choice of 5' and 3' elements used to drive expression of the antibody gene. These results demonstrate the utility of alga as an expression platform for recombinant proteins, and describe a new type of single chain antibody containing the entire heavy chain protein, including the Fc domain.

  20. Fine-scale genetic breaks driven by historical range dynamics and ongoing density-barrier effects in the estuarine seaweed Fucus ceranoides L.

    PubMed Central

    2012-01-01

    Background Factors promoting the emergence of sharp phylogeographic breaks include restricted dispersal, habitat discontinuity, physical barriers, disruptive selection, mating incompatibility, genetic surfing and secondary contact. Disentangling the role of each in any particular system can be difficult, especially when species are evenly distributed across transition zones and dispersal barriers are not evident. The estuarine seaweed Fucus ceranoides provides a good example of highly differentiated populations along its most persistent distributional range at the present rear edge of the species distribution, in NW Iberia. Intrinsic dispersal restrictions are obvious in this species, but have not prevented F. ceranoides from vastly expanding its range northwards following the last glaciation, implying that additional factors are responsible for the lack of connectivity between neighbouring southern populations. In this study we analyze 22 consecutive populations of F. ceranoides along NW Iberia to investigate the processes generating and maintaining the observed high levels of regional genetic divergence. Results Variation at seven microsatellite loci and at mtDNA spacer sequences was concordant in revealing that Iberian F. ceranoides is composed of three divergent genetic clusters displaying nearly disjunct geographical distributions. Structure and AFC analyses detected two populations with an admixed nuclear background. Haplotypic diversity was high in the W sector and very low in the N sector. Within each genetic cluster, population structure was also pervasive, although shallower. Conclusions The deep divergence between sectors coupled with the lack of support for a role of oceanographic barriers in defining the location of breaks suggested 1) that the parapatric genetic sectors result from the regional reassembly of formerly vicariant sub-populations, and 2) that the genetic discontinuities at secondary contact zones (and elsewhere) are maintained despite

  1. The biogeochemical effect of seaweeds upon close-to natural concentrations of dissolved iodate and iodide in seawater Preliminary study with Laminaria digitata and Fucus serratus

    NASA Astrophysics Data System (ADS)

    Truesdale, Victor W.

    2008-06-01

    Toward assessing the biogeochemical significance of seaweeds in relation to dissolved iodine in seawater, the effect of whole seaweeds ( Laminaria digitata and Fucus serratus) upon iodide and iodate, at essentially natural concentrations, has been studied. The weeds were carefully removed from the sub-littoral zone of the Menai Straits and exposed to iodide and iodate at their natural temperature (6 °C), but under continuous illumination. Laminaria digitata was found to decrease the concentration of iodate with an exponential rate constant of 0.008-0.24 h -1. This is a newly discovered process which, if substantiated, will require an entirely new mechanism. Generally, apparent iodide concentration increased except in a run with seawater augmented with iodide, where it first decreased. The rate constant for loss of iodide was 0.014-0.16 h -1. Meanwhile, F. serratus was found not to decrease iodate concentrations, as did L. digitata. Indeed, after ˜30 h iodate concentrations increased, suggesting that the weed may take in iodide before oxidising and releasing it. If substantiated, this finding may offer a way into one of the most elusive of processes within the iodine cycle - iodide oxidation. With both seaweeds sustained long-term increases of apparent iodide concentration are most easily explained as a secretion by the weeds of organic matter which is capable of reducing the Ce(IV) reagent used in determination of total iodine. Modelling of the catalytic method used is provided to support this contention. The possibility of developing this to measure the strain that seaweeds endure in this kind of biogeochemical flux experiment is discussed. A Chemical Oxygen Demand type of approach is applied using Ce(IV) as oxidant. The results of the iodine experiments are contrasted with the several investigations of 131I interaction with seaweeds, which have routinely used discs of weed cut from the frond. It is argued that experiments conducted with stable iodine may

  2. Recovery of dairy manure nutrients by benthic freshwater algae.

    PubMed

    Wilkie, Ann C; Mulbry, Walter W

    2002-08-01

    Harnessing solar energy to grow algal biomass on wastewater nutrients could provide a holistic solution to nutrient management problems on dairy farms. The production of algae from a portion of manure nutrients to replace high-protein feed supplements which are often imported (along with considerable nutrients) onto the farm could potentially link consumption and supply of on-farm nutrients. The objective of this research was to assess the ability of benthic freshwater algae to recover nutrients from dairy manure and to evaluate nutrient uptake rates and dry matter/crude protein yields in comparison to a conventional cropping system. Benthic algae growth chambers were operated in semi-batch mode by continuously recycling wastewater and adding manure inputs daily. Using total nitrogen (TN) loading rates of 0.64-1.03 g m(-2) d(-1), the dried algal yields were 5.3-5.5 g m(-2) d(-1). The dried algae contained 1.5-2.1% P and 4.9-7.1% N. At a TN loading rate of 1.03 g m(-2) d(-1), algal biomass contained 7.1% N compared to only 4.9% N at a TN loading rate of 0.64 g m(-2) d(-1). In the best case, algal biomass had a crude protein content of 44%, compared to a typical corn silage protein content of 7%. At a dry matter yield of 5.5 g m(-2) d(-1), this is equivalent to an annual N uptake rate of 1,430 kg ha(-1) yr(-1). Compared to a conventional corn/rye rotation, such benthic algae production rates would require 26% of the land area requirements for equivalent N uptake rates and 23% of the land area requirements on a P uptake basis. Combining conventional cropping systems with an algal treatment system could facilitate more efficient crop production and farm nutrient management, allowing dairy operations to be environmentally sustainable on fewer acres.

  3. Photosynthetic H2 metabolism in Chlamydomonas reinhardtii (unicellular green algae).

    PubMed

    Melis, Anastasios

    2007-10-01

    Unicellular green algae have the ability to operate in two distinctly different environments (aerobic and anaerobic), and to photosynthetically generate molecular hydrogen (H2). A recently developed metabolic protocol in the green alga Chlamydomonas reinhardtii permitted separation of photosynthetic O2-evolution and carbon accumulation from anaerobic consumption of cellular metabolites and concomitant photosynthetic H2-evolution. The H2 evolution process was induced upon sulfate nutrient deprivation of the cells, which reversibly inhibits photosystem-II and O2-evolution in their chloroplast. In the absence of O2, and in order to generate ATP, green algae resorted to anaerobic photosynthetic metabolism, evolved H2 in the light and consumed endogenous substrate. This study summarizes recent advances on green algal hydrogen metabolism and discusses avenues of research for the further development of this method. Included is the mechanism of a substantial tenfold starch accumulation in the cells, observed promptly upon S-deprivation, and the regulated starch and protein catabolism during the subsequent H2-evolution. Also discussed is the function of a chloroplast envelope-localized sulfate permease, and the photosynthesis-respiration relationship in green algae as potential tools by which to stabilize and enhance H2 metabolism. In addition to potential practical applications of H2, approaches discussed in this work are beginning to address the biochemistry of anaerobic H2 photoproduction, its genes, proteins, regulation, and communication with other metabolic pathways in microalgae. Photosynthetic H2 production by green algae may hold the promise of generating a renewable fuel from nature's most plentiful resources, sunlight and water. The process potentially concerns global warming and the question of energy supply and demand.

  4. Photoreduction of chromium(VI) in the presence of algae, Chlorella vulgaris.

    PubMed

    Deng, Lin; Wang, Hongli; Deng, Nansheng

    2006-11-16

    In this thesis, the photochemical reduction of hexavalent chromium Cr(VI) in the presence of algae, Chlorella vulgaris, was investigated under the irradiation of metal halide lamps (lambda = 365 nm, 250 W). The affecting factors of photochemical reduction were studied in detail, such as exposure time, initial Cr(VI) concentration, initial algae concentration and pH. The rate of Cr(VI) photochemical reduction increased with algae concentration increasing, exposure time increasing, initial Cr(VI) concentration decreasing and the decrease of pH. When pH increased to 6, the rate of Cr(VI) photochemical reduction nearly vanished. When initial Cr(VI) concentration ranged from 0.4 to 1.0 mg L(-1) and initial algae concentration ranged from ABS(algae) (the absorbency of algae) = 0.025 to ABS(algae) = 0.180, According to the results of kinetic analyses, the kinetic equation of Cr(VI) photochemical reduction in aqueous solution with algae under 250 W metal halide lamps was V0 = kC(0)(0.1718)A(algae)(0.5235) (C0 was initial concentration of Cr(VI); A(algae) was initial concentration of algae) under the condition of pH 4.

  5. Screening of antimicrobial activity of macroalgae extracts from the Moroccan Atlantic coast.

    PubMed

    El Wahidi, M; El Amraoui, B; El Amraoui, M; Bamhaoud, T

    2015-05-01

    The aim of this work is the screening of the antimicrobial activity of seaweed extracts against pathogenic bacteria and yeasts. The antimicrobial activity of the dichloromethane and ethanol extracts of ten marine macroalgae collected from the Moroccan's Atlantic coast (El-Jadida) was tested against two Gram+ (Bacillus subtilis and Staphylococcus aureus) and two Gram- (Escherichia coli and Pseudomonas aeruginosa) human pathogenic bacteria, and against two pathogenic yeasts (Candida albicans and Cryptococcus neoformans) using the agar disk-diffusion method. Seven algae (70%) of ten seaweeds are active against at least one pathogenic microorganisms studied. Five (50%) are active against the two studied yeast with an inhibition diameter greater than 15 mm for Cystoseira brachycarpa. Six (60%) seaweeds are active against at least one studied bacteria with five (50%) algae exhibiting antibacterial inhibition diameter greater than 15 mm. Cystoseira brachycarpa, Cystoseira compressa, Fucus vesiculosus, and Gelidium sesquipedale have a better antimicrobial activity with a broad spectrum antimicrobial and are a potential source of antimicrobial compounds and can be subject of isolation of the natural antimicrobials.

  6. Primary productivity of angiosperm and macroalgae dominated habitats in a New England salt marsh: a comparative analysis

    USGS Publications Warehouse

    Roman, C.T.; Able, K.W.; Lazzari, M.A.; Heck, K.L.

    1990-01-01

    Net primary productivity estimates were made for the major macrophyte dominated habitats of the Nauset Marsh system, Cape Cod, Massachusetts. Above-ground primary productivity of short form Spartina alterniflora, the dominant habitat of the system, was 664 g m-2 y-1. Productivity of the other dominant angiosperm (Zostera marina) was estimated to range from 444?987 g m-2 y-1. The marsh creekbank habitat was dominated by an intertidal zone of fucoid algae (Ascophyllum nodosum ecad. scorpioides, 1179 g m-2 y-1; Fucus vesiculosus, 426 g m-2 y-1), mixed intertidal filamentous algae (91 g m-2 y-1), and a subtidal zone of assorted macroalgae (68 g m-2 y-1). Intertidal mudflats were dominated by Cladophora gracilis, with net production ranging from 59?637 g m-2 y-1. These angiosperm and macrophyte and macrophyte dominated habitats produce over 3 ? 106 kg y-1 of biomass (1?2 ? 106 kg carbon y-1). Twenty-eight per cent (28%) of this carbon production is derived from the Zostera and macroalgae habitats. Although S. alterniflora is considered the major macrophyte primary producer in Nauset Marsh and other north temperate salt marshes, it is concluded that other habitats also contribute significantly to total system carbon production.

  7. Comparison of a static and a dynamic in vitro model to estimate the bioaccessibility of As, Cd, Pb and Hg from food reference materials Fucus sp. (IAEA-140/TM) and Lobster hepatopancreas (TORT-2).

    PubMed

    Torres-Escribano, Silvia; Denis, Sylvain; Blanquet-Diot, Stéphanie; Calatayud, Marta; Barrios, Laura; Vélez, Dinoraz; Alric, Monique; Montoro, Rosa

    2011-01-01

    Bioaccessibility, the fraction of an element solubilized during gastrointestinal digestion and available for absorption, is a factor that should be considered when evaluating the health risk of contaminants from food. Static and dynamic models that mimic human physiological conditions have been used to evaluate bioaccessibility. This preliminary study compares the bioaccessibility of arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) in two food certified reference materials (CRMs) (seaweed: Fucus sp., IAEA-140/TM; Lobster hepatopancreas: TORT-2), using two in vitro gastrointestinal digestion methods: a static method (SM) and a dynamic multicompartment method (TIM-1). There are significant differences (p<0.05) between the bioaccessible values of As, Cd, Pb and Hg obtained by SM and TIM-1 in the two CRMs. The specific form in which the elements studied are present in the CRM may help to explain the bioaccessibility values obtained.

  8. Green Algae as Model Organisms for Biological Fluid Dynamics.

    PubMed

    Goldstein, Raymond E

    2015-01-01

    In the past decade the volvocine green algae, spanning from the unicellular Chlamydomonas to multicellular Volvox, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 μm to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these remarkable organisms.

  9. Green Algae as Model Organisms for Biological Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Goldstein, Raymond E.

    2015-01-01

    In the past decade, the volvocine green algae, spanning from the unicellular Chlamydomonas to multicellular Volvox, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 μm to several millimeters), their geometric regularity, the ease with which they can be cultured, and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these remarkable organisms.

  10. Hydrostatic factors affect the gravity responses of algae and roots

    NASA Technical Reports Server (NTRS)

    Staves, Mark P.; Wayne, Randy; Leopold, A. C.

    1991-01-01

    The hypothesis of Wayne et al. (1990) that plant cells perceive gravity by sensing a pressure differential between the top and the bottom of the cell was tested by subjecting rice roots and cells of Caracean algae to external solutions of various densities. It was found that increasing the density of the external medium had a profound effect on the polar ratio (PR, the ratio between velocities of the downwardly and upwardly streaming cytoplasm) of the Caracean algae cells. When these cells were placed in solutions of denser compound, the PR decreased to less than 1, as the density of the external medium became higher than that of the cell; thus, the normal gravity-induced polarity was reversed, indicating that the osmotic pressure of the medium affects the cell's ability to respond to gravity. In rice roots, an increase of the density of the solution inhibited the rate of gravitropism. These results agree with predictions of a hydrostatic model for graviperception.

  11. Plant algae method for arsenic removal from arsenic contaminated groundwater.

    PubMed

    de la Paix, Mupenzi Jean; Lanhai, Li; de Dieu, Habumugisha Jean; John, Maina Nyongesah

    2012-01-01

    Field studies were carried out in Urumqi River Basin in Northwest China. The study focused on experimentation on a plant algae method that was tested by taking various water chemistries into consideration. The results from a greenhouse experiment evaluated for four doses of P (0, 100, 200, and 300 μmol/L) using two ferns (30 and 60 day old) on 15 L of contaminated groundwater per plant revealed that the biomass of 30-day old ferns gained was higher than 60-day fern. As solution-P increased from 0 to 450 μmol/L, Phosphorus concentration in the fronds increased from 1.9 to 3.9 mg/kg and 1.95 to 4.0 mg/kg for 30-d and 60-d ferns respectively. This study showed that the plant algae method may be a good solution to maximize arsenic uptake in the short term under normal climatic conditions.

  12. Production of phthalate esters by nuisance freshwater algae and cyanobacteria.

    PubMed

    Babu, Bakthavachalam; Wu, Jiunn-Tzong

    2010-10-01

    Phthalate esters are widely distributed pollutants which originate from synthetic plasticizer and are known to act as toxicants as well as environmental pheromones in the aquatic ecosystems. From investigating sixteen species of freshwater algae and cyanobacteria we revealed that some of them were capable of producing either di(n-butyl)phthalate (DBP) or mono(2-ethylhexyl)phthalate (MEHP) or both. These phthalate esters would be released into the environment under stress conditions. The incubation of the cells in culture medium containing NaH(13)CO(3) confirmed that both phthalates were de novo synthesized by the studied cells. This study suggested that the nuisance freshwater micro-algae and cyanobacteria growing in eutrophic waters might affect the aquatic ecosystem via the production of these phthalate esters.

  13. Proton channels in algae: reasons to be excited.

    PubMed

    Taylor, Alison R; Brownlee, Colin; Wheeler, Glen L

    2012-11-01

    A fundamental requirement of all eukaryotes is the ability to translocate protons across membranes. This is critical in bioenergetics, for compartmentalized metabolism, and to regulate intracellular pH (pH(i)) within a range that is compatible with cellular metabolism. Plants, animals, and algae utilize specialized transport machinery for membrane energization and pH homeostasis that reflects the prevailing ionic conditions in which they evolved. The recent characterization of H(+)-permeable channels in marine and freshwater algae has led to the discovery of novel functions for these transport proteins in both cellular pH homeostasis and sensory biology. Here we review the potential implications for understanding the origins and evolution of membrane excitability and the phytoplankton-based marine ecosystem responses to ocean acidification.

  14. Marine polysaccharides from algae with potential biomedical applications.

    PubMed

    de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Bernardo; de Morais, Rui Manuel Santos Costa

    2015-05-15

    There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae.

  15. Sodium, potassium-atpases in algae and oomycetes.

    PubMed

    Barrero-Gil, Javier; Garciadeblás, Blanca; Benito, Begoña

    2005-08-01

    We have investigated the presence of K(+)-transporting ATPases that belong to the phylogenetic group of animal Na(+),K(+)-ATPases in the Pythium aphanidermatum Stramenopile oomycete, the Porphyra yezoensis red alga, and the Udotea petiolata green alga, by molecular cloning and expression in heterologous systems. PCR amplification and search in EST databases allowed one gene to be identified in each species that could encode ATPases of this type. Phylogenetic analysis of the sequences of these ATPases revealed that they cluster with ATPases of animal origin, and that the algal ATPases are closer to animal ATPases than the oomycete ATPase is. The P. yezoensis and P. aphanidermatum ATPases were functionally expressed in Saccharomyces cerevisiae and Escherichia coli alkali cation transport mutants. The aforementioned cloning and complementary searches in silicio for H(+)- and Na(+),K(+)-ATPases revealed a great diversity of strategies for plasma membrane energization in eukaryotic cells different from typical animal, plant, and fungal cells.

  16. Green Algae as Model Organisms for Biological Fluid Dynamics*

    PubMed Central

    Goldstein, Raymond E.

    2015-01-01

    In the past decade the volvocine green algae, spanning from the unicellular Chlamydomonas to multicellular Volvox, have emerged as model organisms for a number of problems in biological fluid dynamics. These include flagellar propulsion, nutrient uptake by swimming organisms, hydrodynamic interactions mediated by walls, collective dynamics and transport within suspensions of microswimmers, the mechanism of phototaxis, and the stochastic dynamics of flagellar synchronization. Green algae are well suited to the study of such problems because of their range of sizes (from 10 μm to several millimetres), their geometric regularity, the ease with which they can be cultured and the availability of many mutants that allow for connections between molecular details and organism-level behavior. This review summarizes these recent developments and highlights promising future directions in the study of biological fluid dynamics, especially in the context of evolutionary biology, that can take advantage of these remarkable organisms. PMID:26594068

  17. A New Noncalcified Dasycladalean Alga from the Silurian of Wisconsin

    USGS Publications Warehouse

    LoDuca, S.T.; Kluessendorf, Joanne; Mikulic, Donald G.

    2003-01-01

    Noncalcified thalli, consisting of a narrow main axis with numerous branched hairlike laterals in whorls and a subapical array of undivided clavate laterals, from the Silurian (Llandovery) Brandon Bridge Formation of southeastern Wisconsin, constitute the basis for a new genus and species of dasycladalean alga, Heterocladus waukeshaensis. A relationship within the family Triploporellaceae is indicated by the whorled arrangement of the laterals and the absence of gametophores on mature specimens. A compilation of occurrence data suggests that noncalcified dasyclads, as a whole, were more abundant and diverse during the Ordovician and Silurian than at any other time in their history. The heterocladous thallus architecture of this alga adds to a wide range of morphological variation documented among Ordovician and Silurian dasyclads, the sum of which indicates that Dasycladales underwent a significant evolutionary radiation during the early Paleozoic.

  18. Biosorption of Lead from Wastewater Using Fresh Water Algae Chlorella.

    PubMed

    Kanchana, S; Jeyanthi, J

    2014-04-01

    The potential use of fresh water algae Chlorella to sorb lead ions from wastewater was evaluated in this study. Fourier transform infra-red analysis of algal species revealed the presence of amino, carboxylic, hydroxyl and carbonyl groups, which were responsible for biosorption of lead ions. Batch sorption experiments were performed to determine the effects of contact time, biosorbent dosage and pH on the adsorption of Pb2+ ions. The optimum conditions of biosorbent dosage, pH and contact time were found to be l0 g/L, 5 and 100 min respectively. The applicability of the Langmuir and Freundlich isotherms for representation of the experimental data was investigated. The adsorption of lead ions on the algae Chlorella fitted well with Freundlich isotherm with a very high correlation coefficient.

  19. Recurring patterns in bacterioplankton dynamics during coastal spring algae blooms

    PubMed Central

    Teeling, Hanno; Fuchs, Bernhard M; Bennke, Christin M; Krüger, Karen; Chafee, Meghan; Kappelmann, Lennart; Reintjes, Greta; Waldmann, Jost; Quast, Christian; Glöckner, Frank Oliver; Lucas, Judith; Wichels, Antje; Gerdts, Gunnar; Wiltshire, Karen H; Amann, Rudolf I

    2016-01-01

    A process of global importance in carbon cycling is the remineralization of algae biomass by heterotrophic bacteria, most notably during massive marine algae blooms. Such blooms can trigger secondary blooms of planktonic bacteria that consist of swift successions of distinct bacterial clades, most prominently members of the Flavobacteriia, Gammaproteobacteria and the alphaproteobacterial Roseobacter clade. We investigated such successions during spring phytoplankton blooms in the southern North Sea (German Bight) for four consecutive years. Dense sampling and high-resolution taxonomic analyses allowed the detection of recurring patterns down to the genus level. Metagenome analyses also revealed recurrent patterns at the functional level, in particular with respect to algal polysaccharide degradation genes. We, therefore, hypothesize that even though there is substantial inter-annual variation between spring phytoplankton blooms, the accompanying succession of bacterial clades is largely governed by deterministic principles such as substrate-induced forcing. DOI: http://dx.doi.org/10.7554/eLife.11888.001 PMID:27054497

  20. Marine Polysaccharides from Algae with Potential Biomedical Applications

    PubMed Central

    de Jesus Raposo, Maria Filomena; de Morais, Alcina Maria Bernardo; de Morais, Rui Manuel Santos Costa

    2015-01-01

    There is a current tendency towards bioactive natural products with applications in various industries, such as pharmaceutical, biomedical, cosmetics and food. This has put some emphasis in research on marine organisms, including macroalgae and microalgae, among others. Polysaccharides with marine origin constitute one type of these biochemical compounds that have already proved to have several important properties, such as anticoagulant and/or antithrombotic, immunomodulatory ability, antitumor and cancer preventive, antilipidaemic and hypoglycaemic, antibiotics and anti-inflammatory and antioxidant, making them promising bioactive products and biomaterials with a wide range of applications. Their properties are mainly due to their structure and physicochemical characteristics, which depend on the organism they are produced by. In the biomedical field, the polysaccharides from algae can be used in controlled drug delivery, wound management, and regenerative medicine. This review will focus on the biomedical applications of marine polysaccharides from algae. PMID:25988519

  1. A preliminary study on automated freshwater algae recognition and classification system

    PubMed Central

    2012-01-01

    Background Freshwater algae can be used as indicators to monitor freshwater ecosystem condition. Algae react quickly and predictably to a broad range of pollutants. Thus they provide early signals of worsening environment. This study was carried out to develop a computer-based image processing technique to automatically detect, recognize, and identify algae genera from the divisions Bacillariophyta, Chlorophyta and Cyanobacteria in Putrajaya Lake. Literature shows that most automated analyses and identification of algae images were limited to only one type of algae. Automated identification system for tropical freshwater algae is even non-existent and this study is partly to fill this gap. Results The development of the automated freshwater algae detection system involved image preprocessing, segmentation, feature extraction and classification by using Artificial neural networks (ANN). Image preprocessing was used to improve contrast and remove noise. Image segmentation using canny edge detection algorithm was then carried out on binary image to detect the algae and its boundaries. Feature extraction process was applied to extract specific feature parameters from algae image to obtain some shape and texture features of selected algae such as shape, area, perimeter, minor and major axes, and finally Fourier spectrum with principal component analysis (PCA) was applied to extract some of algae feature texture. Artificial neural network (ANN) is used to classify algae images based on the extracted features. Feed-forward multilayer perceptron network was initialized with back propagation error algorithm, and trained with extracted database features of algae image samples. System's accuracy rate was obtained by comparing the results between the manual and automated classifying methods. The developed system was able to identify 93 images of selected freshwater algae genera from a total of 100 tested images which yielded accuracy rate of 93%. Conclusions This study

  2. The problems of Prochloron. [evolution of green algae

    NASA Technical Reports Server (NTRS)

    Lewin, R. A.

    1983-01-01

    Prokaryotic green algae (prochlorophytes), which contain chlorophylls a and b but no bilin pigments, may be phylogenetically related to ancestral chloroplasts if symbiogenesis occurred. They may be otherwise related to eukaryotic chlorophytes. They could have evolved from cyanophytes by loss of phycobilin and gain of chlorophyll b synthesis. These possibilities are briefly discussed. Relevant evidence from biochemical studies in many collaborative laboratories is now becoming available for the resolution of such questions.

  3. Use of Unicellular Algae for Evaluation of Potential Aquatic Contaminants

    DTIC Science & Technology

    1977-05-01

    UNICELLULAR ALGAE FOR EVALUATION First Annual Report OF POTENTIAL AQUATIC CONTAMINANTS 1 Sep - 31 May 76 6. PERFORMING ORG. REPORT NUMBER ANNUAL...p’dioctyldephrylamine RJ-5 Phenyl-a-napthylamine Lubrication Additives Unsymmetrical Dimethylhydrazine Hydrazine Symmetrical Dimethylhydrazine [continusd on .bnckj 20...Force Contract AF33615-76-C-5005. Work under this portion of the contract covers the period September 1 , 1975 to May 31, 1976. The project is

  4. Treatment efficacy of algae-based sewage treatment plants.

    PubMed

    Mahapatra, Durga Madhab; Chanakya, H N; Ramachandra, T V

    2013-09-01

    Lagoons have been traditionally used in India for decentralized treatment of domestic sewage. These are cost effective as they depend mainly on natural processes without any external energy inputs. This study focuses on the treatment efficiency of algae-based sewage treatment plant (STP) of 67.65 million liters per day (MLD) capacity considering the characteristics of domestic wastewater (sewage) and functioning of the treatment plant, while attempting to understand the role of algae in the treatment. STP performance was assessed by diurnal as well as periodic investigations of key water quality parameters and algal biota. STP with a residence time of 14.3 days perform moderately, which is evident from the removal of total chemical oxygen demand (COD) (60 %), filterable COD (50 %), total biochemical oxygen demand (BOD) (82 %), and filterable BOD (70 %) as sewage travels from the inlet to the outlet. Furthermore, nitrogen content showed sharp variations with total Kjeldahl nitrogen (TKN) removal of 36 %; ammonium N (NH4-N) removal efficiency of 18 %, nitrate (NO3-N) removal efficiency of 22 %, and nitrite (NO2-N) removal efficiency of 57.8 %. The predominant algae are euglenoides (in facultative lagoons) and chlorophycean members (maturation ponds). The drastic decrease of particulates and suspended matter highlights heterotrophy of euglenoides in removing particulates.

  5. Origins of multicellular complexity: Volvox and the volvocine algae.

    PubMed

    Herron, Matthew D

    2016-03-01

    The collection of evolutionary transformations known as the 'major transitions' or 'transitions in individuality' resulted in changes in the units of evolution and in the hierarchical structure of cellular life. Volvox and related algae have become an important model system for the major transition from unicellular to multicellular life, which touches on several fundamental questions in evolutionary biology. The Third International Volvox Conference was held at the University of Cambridge in August 2015 to discuss recent advances in the biology and evolution of this group of algae. Here, I highlight the benefits of integrating phylogenetic comparative methods and experimental evolution with detailed studies of developmental genetics in a model system with substantial genetic and genomic resources. I summarize recent research on Volvox and its relatives and comment on its implications for the genomic changes underlying major evolutionary transitions, evolution and development of complex traits, evolution of sex and sexes, evolution of cellular differentiation and the biophysics of motility. Finally, I outline challenges and suggest future directions for research into the biology and evolution of the volvocine algae.

  6. Phycobilisome Heterogeneity in the Red Alga Porphyra umbilicalis1

    PubMed Central

    Algarra, Patricia; Thomas, Jean-Claude; Mousseau, Anne

    1990-01-01

    Phycobilisomes were isolated from Rhodophyceae brought from the field (Porphyra umbilicalis) or grown in culture under laboratory conditions (Antithamnion glanduliferum). In P. umbilicalis two kinds of well-coupled (ellipsoidal and hemidiscoidal) phycobilisomes were detected, in contrast to A. glanduliferum cultured algae in which only one kind of well-coupled, ellipsoidaltype phycobilisome appeared. The new phycobilisome-type particle detected in P. umbilicalis is characterized by an impoverishment in R-phycoerythrin and by sedimentation at lower density. The comparison between both phycobilisomes of P. umbilicalis allows determination of the presence of one colorless linker polypeptide (30 kilodaltons) associated with R-phycocyanin and allophycocyanin and two (40 and 38 kilodaltons) associated to R-phycoerythrin. The percentage of linker polypeptides associated with this pigment is low in the new phycobilisome-like particle detected. This suggests that part of the R-phycoerythrin is less strongly bound to the phycobilisome than the other pigments. This feature could probably explain the existence of two kinds of phycobilisomes as intermediary steps of phycobilisome organization in algae exposed to rapid changes in environmental factors. In contrast, algae growing in culture and adapted to specific conditions do not present intermediary organization steps. Polypeptide composition and identification are given for this phycobilisome-like particle. Images Figure 4 Figure 5 PMID:16667317

  7. Partitioning of monomethylmercury between freshwater algae and water.

    PubMed

    Miles, C J; Moye, H A; Phlips, E J; Sargent, B

    2001-11-01

    Phytoplankton-water monomethylmercury (MeHg) partition constants (KpI) have been determined in the laboratory for two green algae Selenastrum capricornutum and Cosmarium botrytis, the blue-green algae Schizothrix calcicola, and the diatom Thallasiosira spp., algal species that are commonly found in natural surface waters. Two methods were used to determine KpI, the Freundlich isotherm method and the flow-through/dialysis bag method. Both methods yielded KpI values of about 10(6.6) for S. capricornutum and were not significantly different. The KpI for the four algae studied were similar except for Schizothrix, which was significantly lower than S. capricornutum. The KpI for MeHg and S. capricornutum (exponential growth) was not significantly different in systems with predominantly MeHgOH or MeHgCl species. This is consistent with other studies that show metal speciation controls uptake kinetics, but the reactivity with intracellular components controls steady-state concentrations. Partitioning constants determined with exponential and stationary phase S. capricornutum cells at the same conditions were not significantly different, while the partitioning constant for exponential phase, phosphorus-limited cells was significantly lower, suggesting that P-limitation alters the ecophysiology of S. capricornutum sufficiently to impact partitioning, which may then ultimately affect mercury levels in higher trophic species.

  8. Distribution of periphytic algae in wetlands (Palm swamps, Cerrado), Brazil.

    PubMed

    Dunck, B; Nogueira, I S; Felisberto, S A

    2013-05-01

    The distribution of periphytic algae communities depends on various factors such as type of substrate, level of disturbance, nutrient availability and light. According to the prediction that impacts of anthropogenic activity provide changes in environmental characteristics, making impacted Palm swamps related to environmental changes such as deforestation and higher loads of nutrients via allochthonous, the hypothesis tested was: impacted Palm swamps have higher richness, density, biomass and biovolume of epiphytic algae. We evaluated the distribution and structure of epiphytic algae communities in 23 Palm swamps of Goiás State under different environmental impacts. The community structure attributes here analyzed were composition, richness, density, biomass and biovolume. This study revealed the importance of the environment on the distribution and structuration of algal communities, relating the higher values of richness, biomass and biovolume with impacted environments. Acidic waters and high concentration of silica were important factors in this study. Altogether 200 taxa were identified, and the zygnemaphycea was the group most representative in richness and biovolume, whereas the diatoms, in density of studied epiphyton. Impacted Palm swamps in agricultural area presented two indicator species, Gomphonema lagenula Kützing and Oedogonium sp, both related to mesotrophic to eutrophic conditions for total nitrogen concentrations of these environments.

  9. Multicellularity in green algae: upsizing in a walled complex

    PubMed Central

    Domozych, David S.; Domozych, Catherine E.

    2014-01-01

    Modern green algae constitute a large and diverse taxonomic assemblage that encompasses many multicellular phenotypes including colonial, filamentous, and parenchymatous forms. In all multicellular green algae, each cell is surrounded by an extracellular matrix (ECM), most often in the form of a cell wall. Volvocalean taxa like Volvox have an elaborate, gel-like, hydroxyproline rich glycoprotein covering that contains the cells of the colony. In “ulvophytes,” uronic acid-rich and sulfated polysaccharides are the likely adhesion agents that maintain the multicellular habit. Charophytes also produce polysaccharide-rich cell walls and in late divergent taxa, pectin plays a critical role in cell adhesion in the multicellular complex. Cell walls are products of coordinated interaction of membrane trafficking, cytoskeletal dynamics and the cell’s signal transduction machinery responding both to precise internal clocks and external environmental cues. Most often, these activities must be synchronized with the secretion, deposition and remodeling of the polymers of the ECM. Rapid advances in molecular genetics, cell biology and cell wall biochemistry of green algae will soon provide new insights into the evolution and subcellular processes leading to multicellularity. PMID:25477895

  10. Unveiling privacy: advances in microtomography of coralline algae.

    PubMed

    Torrano-Silva, Beatriz N; Ferreira, Simone Gomes; Oliveira, Mariana C

    2015-05-01

    Marine calcareous algae are widespread in oceans of the world and known for their calcified cell walls and the generation of rhodolith beds that turn sandy bottoms into a complex structured ecosystem with high biodiversity. Rhodoliths are unattached, branching, crustose benthic marine red algae; they provide habitat for a rich variety of marine invertebrates. The resultant excavation is relevant to sediment production, while is common that the fragments or the whole specimens result in vast fossil deposits formed by rich material that can be "mined" for biological and geological data. Accordingly, microtomography (μCT) may enable a detailed investigation of biological and geological signatures preserved within the rhodolith structure in a non-destructive approach that is especially relevant when analyzing herbaria collections or rare samples. Therefore, we prepared coralline algae samples and submitted them to a range of capabilities provided by the SkyScan1176 micro-CT scanner, including reconstruction, virtual slicing, and pinpointing biological and geological signatures. To this end, polychaetes and mollusk shells, or their excavations, coral nucleation, sediment deposits and conceptacles were all observed. Although a similar technique has been applied previously to samples of living rhodoliths in Brazil, we show, for the first time, its successful application to fossil rhodoliths. We also provide a detailed working protocol and discuss the advantages and limitations of the microtomography within the rhodoliths.

  11. Exploitation of marine algae: biogenic compounds for potential antifouling applications.

    PubMed

    Bhadury, Punyasloke; Wright, Phillip C

    2004-08-01

    Marine algae are one of the largest producers of biomass in the marine environment. They produce a wide variety of chemically active metabolites in their surroundings, potentially as an aid to protect themselves against other settling organisms. These active metabolites, also known as biogenic compounds, produced by several species of marine macro- and micro-algae, have antibacterial, antialgal, antimacrofouling and antifungal properties, which are effective in the prevention of biofouling, and have other likely uses, e.g. in therapeutics. The isolated substances with potent antifouling activity belong to groups of fatty acids, lipopeptides, amides, alkaloids, terpenoids, lactones, pyrroles and steroids. These biogenic compounds have the potential to be produced commercially using metabolic engineering techniques. Therefore, isolation of biogenic compounds and determination of their structure could provide leads for future development of, for example, environmentally friendly antifouling paints. This paper mainly discusses the successes of such research, and the future applications in the context of understanding the systems biology of micro-algae and cyanobacteria.

  12. Multi-centennial reconstruction of Aleutian climate from coralline algae

    NASA Astrophysics Data System (ADS)

    Williams, B.; Halfar, J.; DeLong, K. L.; Smith, E.; Steneck, R.; Lebednik, P.; Jacob, D. E.; Fietzke, J.; Moore, K.

    2015-12-01

    Long-lived encrusting coralline algae yield robust reconstructions of mid-to-high latitude environmental change from their annually-banded high-magnesium calcite skeleton. The magnesium to calcium ratio measured in their skeleton reflects ambient seawater temperature at the time of formation. Thus, reconstructions from these algae are important to understanding the role of natural modes of climate variability versus that of external carbon dioxide in controlling climate in data sparse regions such as the northern North Pacific Ocean/southern Bering Sea. Here, we reconstruct regional seawater temperature from the skeletons of nine algae specimens from two islands in the Aleutian Archipelago. We find that seawater temperature increased ~1.4°C degrees over the past 350 years. The detrended seawater reconstruction correlates with storminess because storms moving across the North Pacific Ocean bring warmer water to the archipelago. Comparison of the algal seawater temperature reconstruction with instrumental and terrestrial proxy reconstructions reveals that atmospheric teleconnections to North America via the North Pacific storm tracks are not robust before the 20th century. This indicates that North Pacific climate processes inferred from the instrumental records should be cautiously extrapolated when describing earlier non-analogous climates or future climate change.

  13. Cytotoxicity of algae extracts on normal and malignant cells.

    PubMed

    Bechelli, Jeremy; Coppage, Myra; Rosell, Karen; Liesveld, Jane

    2011-01-01

    Algae preparations are commonly used in alternative medicine. We examined the effects of algae extracts on normal hematopoietic cells and leukemia cells. Ethanol extracts were prepared of Dunaliella salina (Dun), Astaxanthin (Ast), Spirulina platensis (Spir), and Aphanizomenon flos-aquae (AFA). Cell viability effects were completed by Annexin staining. Ast and AFA inhibited HL-60 and MV-4-11 whereas Dun and Spir had no effect. Primary AML blasts demonstrated increased apoptosis in AFA. Primary CLL cells showed apoptosis at 24 hours after exposure to Dun, Ast, Spir, and AFA. High AFA concentrations decreased viability of normal marrow cells. Normal CD34+ viability was inhibited by Dun. Dun and AFA inhibited BFU-E, but all extracts inhibited CFU-GM. Cell-cycle analysis of AML cell lines showed G0/G1 arrest in the presence of AFA. These data suggest that algae extracts may inhibit AML cell lines and leukemia blasts, but they may also have potential inhibitory effects on normal hematopoiesis.

  14. Bioaccumulation and toxicity of phenanthrene applied to different freshwater algae

    SciTech Connect

    Hailing-Sorensen, B.; Nyholm, N.; Rucker, N.; Peterson, H.

    1994-12-31

    Phenanthrene, a polycyclic aromatic hydrocarbon of medium lipophilicity (log K{sub ow} = 4.46) was chosen as a model compound for investigating mechanisms of bioaccumulation of hydrophobic chemicals in microalgae and relations between expressed toxicity and bioaccumulation. {sup 14}C labelled phenanthrene was used for easy quantification of its phase distribution. Results obtained with the green algae Selenastrum capricornutum and Scenedesmus armatus will be presented together with additional results from planned experiments with diatoms and cyanobacteria and interpreted considering cell size and lipid content of the different algae, For the same species bioconcentration factors (BCFs) were influenced to some extent by nutritional status and were slightly higher for unwashed cells than for washed cells. Much surprisingly, however, BCFs increased strongly with decreasing cell concentration. With chemostat grown nutrient deficient and washed Selenastrum cells, for example, the following BCF figures (mg phenanthrene/mg dry weight) were found: 3.8{center_dot}10{sup 4} 1.7{center_dot}10{sup 5} and 1.6{center_dot}10{sup 6}. Sorption of phenanthrene onto algae was rapid. Similar results have been reported in the literature for other compounds. The toxicity of phenanthrene increased with decreasing algal cell concentration probably as a result of increasing BCF`S. Toxicity experiments comprised both short term {sup 14}C assimilation assays and growth tests, and the phase distribution of phenanthrene was accounted for.

  15. Bioaccumulation and catabolism of prometryne in green algae.

    PubMed

    Jin, Zhen Peng; Luo, Kai; Zhang, Shuang; Zheng, Qi; Yang, Hong

    2012-04-01

    Investigation on organic xenobiotics bioaccumulation/biodegradation in green algae is of great importance from environmental point of view because widespread distribution of these compounds in agricultural areas has become one of the major problems in aquatic ecosystem. Also, new technology needs to be developed for environmental detection and re-usage of the compounds as bioresources. Prometryne as a herbicide is widely used for killing annual grasses in China and other developing countries. However, overuse of the pesticide results in high risks to contamination to aquatic environments. In this study, we focused on analysis of bioaccumulation and degradation of prometryne in Chlamydomonas reinhardtii, a green alga, along with its adaptive response to prometryne toxicity. C. reinhardtii treated with prometryne at 2.5-12.5 μg L(-1) for 4 d or 7.5 μg L(-1) for 1-6 d accumulated a large quantity of prometryne, with more than 2 mg kg(-1) fresh weight in cells exposed to 10 μg L(-1) prometryne. Moreover, it showed a great ability to degrade simultaneously the cell-accumulated prometryne. Such uptake and catabolism of prometryne led to the rapid removal of prometryne from media. Physiological and molecular analysis revealed that toxicology was associated with accumulation of prometryne in the cells. The biological processes of degradation can be interpreted as an internal tolerance mechanism. These results suggest that the green alga is useful in bioremediation of prometryne-contaminated aquatic ecosystems.

  16. Extraction, Purification, and NMR Analysis of Terpenes from Brown Algae.

    PubMed

    Gaysinski, Marc; Ortalo-Magné, Annick; Thomas, Olivier P; Culioli, Gérald

    2015-01-01

    Algal terpenes constitute a wide and well-documented group of marine natural products with structures differing from their terrestrial plant biosynthetic analogues. Amongst macroalgae, brown seaweeds are considered as one of the richest source of biologically and ecologically relevant terpenoids. These metabolites, mostly encountered in algae of the class Phaeophyceae, are mainly diterpenes and meroditerpenes (metabolites of mixed biogenesis characterized by a toluquinol or a toluquinone nucleus linked to a diterpene moiety).In this chapter, we describe analytical processes commonly employed for the isolation and structural characterization of the main terpenoid constituents obtained from organic extracts of brown algae. The successive steps include (1) extraction of lipidic content from algal samples; (2) purification of terpenes by column chromatography and semi-preparative high-performance liquid chromatography; and (3) structure elucidation of the isolated terpenes by means of 1D and 2D nuclear magnetic resonance (NMR). More precisely, we propose a representative methodology which allows the isolation and structural determination of the monocyclic meroditerpene methoxybifurcarenone (MBFC) from the Mediterranean brown alga Cystoseira amentacea var. stricta. This methodology has a large field of applications and can then be extended to terpenes isolated from other species of the family Sargassaceae.

  17. Enzyme-Enhanced Extraction of Antioxidant Ingredients from Algae.

    PubMed

    Adalbjörnsson, Björn V; Jónsdóttir, Rósa

    2015-01-01

    Marine algae are not only a rich source of dietary fibre, proteins, vitamins, and minerals, but also contain a great variety of secondary metabolites with diverse biological activities. Marine macroalgae are a rich source of various natural antioxidants such as polyphenols, especially phlorotannins (made of polyphloroglucinol units) derived from brown algae, which play an important role in preventing lipid peroxidation. In recent years, a number of potent antioxidant compounds have been isolated and identified from different types of edible seaweeds. Extraction methods commonly used for the isolation of antioxidants are based on conventional water or organic solvent extractions. However, recent advances have shown that enzymatic hydrolysis can achieve higher yield of bioactive compounds from algae. Here we describe a method based on enzymatic hydrolysis which both increases yield and decreases cost associated with organic solvents. This method achieves cell wall disruption and breakdown of internal storage components for more effective release of intracellular bioactive compounds. In addition, hydrolysis of proteins produces peptides which may have antioxidant properties, thus enhancing the bioactivity of the algal extract. The method described can be used for production of extracts from red and brown macroalgal species.

  18. [Quantitative remote sensing retrieval for algae in inland waters].

    PubMed

    Song, Yu; Song, Xiao-Dong; Jiang, Hong; Guo, Zhao-Bing; Guo, Qing-Hai

    2010-04-01

    Chlorophyll is a very important indictor for the eutrophication status of lake water body. Using remotely sensed data to achieve real-time dynamic monitoring of the spatial distribution of chlorophyll has great importance. This paper aims to find the best band for the hyperspectral ratio model of chlorophyll-a, and take advantage of this model to implement remote sensing retrieval of algae in Taihu Lake. By the analysis of the spectral reflectance and water quality sampling data of the surface water body, the regression model between the ratio of reflectance and chlorophyll-a was built, and it was showed that the ratio model between the wavelengths around 700 and 625 nm had a relatively high coefficient value of determination (R2), while the ratio model constructed with 710 nm and visible wavelengths showed a descended R2 following with the increment of the visible wavelengths. Combined with in-situ water samplings analysis and spectral reflectance measurement, the results showed that it's possible to retrieve algae water body using the MODIS green index (GI). The spatial distributions of chlorophyll-a and algae in Taihu Lake were extracted successfully using MODIS data with the algorithm developed in this paper.

  19. Photosynthetic circadian rhythmicity patterns of Symbiodium, the coral endosymbiotic algae

    PubMed Central

    Sorek, Michal; Yacobi, Yosef Z.; Roopin, Modi; Berman-Frank, Ilana; Levy, Oren

    2013-01-01

    Biological clocks are self-sustained endogenous timers that enable organisms (from cyanobacteria to humans) to anticipate daily environmental rhythms, and adjust their physiology and behaviour accordingly. Symbiotic corals play a central role in the creation of biologically rich ecosystems based on mutualistic symbioses between the invertebrate coral and dinoflagellate protists from the genus Symbiodinium. In this study, we experimentally establish that Symbiodinium photosynthesis, both as a free-living unicellular algae and as part of the symbiotic association with the coral Stylophora pistillata, is ‘wired’ to the circadian clock mechanism with a ‘free-run’ cycle close to 24 h. Associated photosynthetic pigments also showed rhythmicity under light/dark conditions and under constant light conditions, while the expression of the oxygen-evolving enhancer 1 gene (within photosystem II) coincided with photosynthetically evolved oxygen in Symbiodinium cultures. Thus, circadian regulation of the Symbiodinium photosynthesis is, however, complicated as being linked to the coral/host that have probably profound physiochemical influence on the intracellular environment. The temporal patterns of photosynthesis demonstrated here highlight the physiological complexity and interdependence of the algae circadian clock associated in this symbiosis and the plasticity of algae regulatory mechanisms downstream of the circadian clock. PMID:23554392

  20. Controlling harmful algae blooms using aluminum-modified clay.

    PubMed

    Liu, Yang; Cao, Xihua; Yu, Zhiming; Song, Xiuxian; Qiu, Lixia

    2016-02-15

    The performances of aluminum chloride modified clay (AC-MC), aluminum sulfate modified clay (AS-MC) and polyaluminum chloride modified clay (PAC-MC) in the removal of Aureococcus anophagefferens were compared, and the potential mechanisms were analyzed according to the dispersion medium, suspension pH and clay surface charges. The results showed that AC-MC and AS-MC had better efficiencies in removing A.anophagefferens than PAC-MC. The removal mechanisms of the three modified clays varied. At optimal coagulation conditions, the hydrolysates of AC and AS were mainly monomers, and they transformed into Al(OH)3(am) upon their addition to algae culture, with the primary mechanism being sweep flocculation. The PAC mainly hydrolyzed to the polyaluminum compounds, which remained stable when added to the algae culture, and the flocculation mainly occurred through polyaluminum compounds. The suspension pH significantly influenced the aluminum hydrolysate and affected the flocculation between the modified clay and algae cells.