Sample records for alga botryococcus braunii

  1. Hydrocarbon production from secondarily treated piggery wastewater by the green alga Botryococcus braunii

    Microsoft Academic Search

    Jin-Young An; Sang-Jun Sim; Jin Suk Lee; Byung Woo Kim

    2003-01-01

    A laboratory study was conducted on the removal of nitrogen and phosphorus from piggery wastewater during growth of Botryococcus braunii UTEX 572, together with measurements of hydrocarbon formation by the alga. The influence was tested of the initial nitrogen and phosphorus concentration on the optimum concentration range for a culture in secondarily treated piggery wastewater. A high cell density (>

  2. Effects of harvesting method and growth stage on the flocculation of the green alga Botryococcus braunii

    Microsoft Academic Search

    S. J. Lee; S.-B. Kim; J.-E. Kim; G.-S. Kwon; B.-D. Yoon; H.-M. Oh

    1998-01-01

    S.J. LEE, S.-B. KIM, J.-E. KIM, G.-S. KWON, B.-D. YOON AND H.-M. OH. 1998.Flocculating activity was determined to evaluate the effective harvesting method and an optimal growth stage for the recovery of the green alga Botryococcus braunii growing in batch cultures. Flocculating activity was highest at 2 weeks of incubation, regardless of harvesting methods. The degree of flocculation was different

  3. A novel alphaproteobacterial ectosymbiont promotes the growth of the hydrocarbon-rich green alga Botryococcus braunii.

    PubMed

    Tanabe, Yuuhiko; Okazaki, Yusuke; Yoshida, Masaki; Matsuura, Hiroshi; Kai, Atsushi; Shiratori, Takashi; Ishida, Ken-Ichiro; Nakano, Shin-Ichi; Watanabe, Makoto M

    2015-01-01

    Botryococcus braunii is a colony-forming green alga that accumulates large amounts of liquid hydrocarbons within the colony. The utilization of B. braunii for biofuel production is however hindered by its low biomass productivity. Here we describe a novel bacterial ectosymbiont (BOTRYCO-2) that confers higher biomass productivity to B. braunii. 16S rDNA analysis indicated that the sequence of BOTRYCO-2 shows low similarity (<90%) to cultured bacterial species and located BOTRYCO-2 within a phylogenetic lineage consisting of uncultured alphaproteobacterial clones. Fluorescence in situ hybridization (FISH) studies and transmission electric microscopy indicated that BOTRYCO-2 is closely associated with B. braunii colonies. Interestingly, FISH analysis of a water bloom sample also found BOTRYCO-2 bacteria in close association with cyanobacterium Microcystis aeruginosa colonies, suggesting that BOTRYCO-2 relatives have high affinity to phytoplankton colonies. A PCR survey of algal bloom samples revealed that the BOTRYCO-2 lineage is commonly found in Microcystis associated blooms. Growth experiments indicated that B. braunii Ba10 can grow faster and has a higher biomass (1.8-fold) and hydrocarbon (1.5-fold) yield in the presence of BOTRYCO-2. Additionally, BOTRYCO-2 conferred a higher biomass yield to BOT-22, one of the fastest growing strains of B. braunii. We propose the species name 'Candidatus Phycosocius bacilliformis' for BOTRYCO-2. PMID:26130609

  4. A novel alphaproteobacterial ectosymbiont promotes the growth of the hydrocarbon-rich green alga Botryococcus braunii

    PubMed Central

    Tanabe, Yuuhiko; Okazaki, Yusuke; Yoshida, Masaki; Matsuura, Hiroshi; Kai, Atsushi; Shiratori, Takashi; Ishida, Ken-ichiro; Nakano, Shin-ichi; Watanabe, Makoto M.

    2015-01-01

    Botryococcus braunii is a colony-forming green alga that accumulates large amounts of liquid hydrocarbons within the colony. The utilization of B. braunii for biofuel production is however hindered by its low biomass productivity. Here we describe a novel bacterial ectosymbiont (BOTRYCO-2) that confers higher biomass productivity to B. braunii. 16S rDNA analysis indicated that the sequence of BOTRYCO-2 shows low similarity (<90%) to cultured bacterial species and located BOTRYCO-2 within a phylogenetic lineage consisting of uncultured alphaproteobacterial clones. Fluorescence in situ hybridization (FISH) studies and transmission electric microscopy indicated that BOTRYCO-2 is closely associated with B. braunii colonies. Interestingly, FISH analysis of a water bloom sample also found BOTRYCO-2 bacteria in close association with cyanobacterium Microcystis aeruginosa colonies, suggesting that BOTRYCO-2 relatives have high affinity to phytoplankton colonies. A PCR survey of algal bloom samples revealed that the BOTRYCO-2 lineage is commonly found in Microcystis associated blooms. Growth experiments indicated that B. braunii Ba10 can grow faster and has a higher biomass (1.8-fold) and hydrocarbon (1.5-fold) yield in the presence of BOTRYCO-2. Additionally, BOTRYCO-2 conferred a higher biomass yield to BOT-22, one of the fastest growing strains of B. braunii. We propose the species name ‘Candidatus Phycosocius bacilliformis’ for BOTRYCO-2. PMID:26130609

  5. Active hydrocarbon biosynthesis and accumulation in a green alga, Botryococcus braunii (race A).

    PubMed

    Hirose, Mana; Mukaida, Fukiko; Okada, Sigeru; Noguchi, Tetsuko

    2013-08-01

    Among oleaginous microalgae, the colonial green alga Botryococcus braunii accumulates especially large quantities of hydrocarbons. This accumulation may be achieved more by storage of lipids in the extracellular space rather than in the cytoplasm, as is the case for all other examined oleaginous microalgae. The stage of hydrocarbon synthesis during the cell cycle was determined by autoradiography. The cell cycle of B. braunii race A was synchronized by aminouracil treatment, and cells were taken at various stages in the cell cycle and cultured in a medium containing [(14)C]acetate. Incorporation of (14)C into hydrocarbons was detected. The highest labeling occurred just after septum formation, when it was about 2.6 times the rate during interphase. Fluorescent and electron microscopy revealed that new lipid accumulation on the cell surface occurred during at least two different growth stages and sites of cells. Lipid bodies in the cytoplasm were not prominent in interphase cells. These lipid bodies then increased in number, size, and inclusions, reaching maximum values just before the first lipid accumulation on the cell surface at the cell apex. Most of them disappeared from the cytoplasm concomitant with the second new accumulation at the basolateral region, where extracellular lipids continuously accumulated. The rough endoplasmic reticulum near the plasma membrane is prominent in B. braunii, and the endoplasmic reticulum was often in contact with both a chloroplast and lipid bodies in cells with increasing numbers of lipid bodies. We discuss the transport pathway of precursors of extracellular hydrocarbons in race A. PMID:23794509

  6. Transformation of Lipid Bodies Related to Hydrocarbon Accumulation in a Green Alga, Botryococcus braunii (Race B)

    PubMed Central

    Uno, Yuki; Nishii, Ichiro; Kagiwada, Satoshi; Okada, Sigeru; Noguchi, Tetsuko

    2013-01-01

    The colonial microalga Botryococcus braunii accumulates large quantities of hydrocarbons mainly in the extracellular space; most other oleaginous microalgae store lipids in the cytoplasm. Botryococcus braunii is classified into three principal races (A, B, and L) based on the types of hydrocarbons. Race B has attracted the most attention as an alternative to petroleum by its higher hydrocarbon contents than the other races and its hydrocarbon components, botryococcenes and methylsqualenes, both can be readily converted into biofuels. We studied race B using fluorescence and electron microscopy, and clarify the stage when extracellular hydrocarbon accumulation occurs during the cell cycle, in a correlation with the behavior and structural changes of the lipid bodies and discussed development of the algal colony. New accumulation of lipids on the cell surface occurred after cell division in the basolateral region of daughter cells. While lipid bodies were observed throughout the cell cycle, their size and inclusions were dynamically changing. When cells began dividing, the lipid bodies increased in size and inclusions until the extracellular accumulation of lipids started. Most of the lipids disappeared from the cytoplasm concomitant with the extracellular accumulation, and then reformed. We therefore hypothesize that lipid bodies produced during the growth of B. braunii are related to lipid secretion. New lipids secreted at the cell surface formed layers of oil droplets, to a maximum depth of six layers, and fused to form flattened, continuous sheets. The sheets that combined a pair of daughter cells remained during successive cellular divisions and the colony increased in size with increasing number of cells. PMID:24339948

  7. Transformation of lipid bodies related to hydrocarbon accumulation in a green alga, Botryococcus braunii (Race B).

    PubMed

    Suzuki, Reiko; Ito, Naoko; Uno, Yuki; Nishii, Ichiro; Kagiwada, Satoshi; Okada, Sigeru; Noguchi, Tetsuko

    2013-01-01

    The colonial microalga Botryococcus braunii accumulates large quantities of hydrocarbons mainly in the extracellular space; most other oleaginous microalgae store lipids in the cytoplasm. Botryococcus braunii is classified into three principal races (A, B, and L) based on the types of hydrocarbons. Race B has attracted the most attention as an alternative to petroleum by its higher hydrocarbon contents than the other races and its hydrocarbon components, botryococcenes and methylsqualenes, both can be readily converted into biofuels. We studied race B using fluorescence and electron microscopy, and clarify the stage when extracellular hydrocarbon accumulation occurs during the cell cycle, in a correlation with the behavior and structural changes of the lipid bodies and discussed development of the algal colony. New accumulation of lipids on the cell surface occurred after cell division in the basolateral region of daughter cells. While lipid bodies were observed throughout the cell cycle, their size and inclusions were dynamically changing. When cells began dividing, the lipid bodies increased in size and inclusions until the extracellular accumulation of lipids started. Most of the lipids disappeared from the cytoplasm concomitant with the extracellular accumulation, and then reformed. We therefore hypothesize that lipid bodies produced during the growth of B. braunii are related to lipid secretion. New lipids secreted at the cell surface formed layers of oil droplets, to a maximum depth of six layers, and fused to form flattened, continuous sheets. The sheets that combined a pair of daughter cells remained during successive cellular divisions and the colony increased in size with increasing number of cells. PMID:24339948

  8. Effect of salinity on growth of green alga Botryococcus braunii and its constituents.

    PubMed

    Rao, A Ranga; Dayananda, C; Sarada, R; Shamala, T R; Ravishankar, G A

    2007-02-01

    Growth of Botryococcus braunii (race 'A') and production of its constituents viz, hydrocarbon, carbohydrate, fatty acid, and carotenoids were influenced by different levels of salinity. Under salinity at 34 mM and 85 mM, 1.7-2.25-fold increase in the relative proportion of palmitic acid and two fold increase in oleic acid were observed. A twofold increase in carotenoid content was noticed at 85 mM salinity with lutein (75% of total carotenoid) as the major carotenoid followed by beta-carotene. The increase in biomass yields and changes in other constituents indicated the influence of salinity and the organism's adaptability to the tested levels of salinity (17 mM to 85 mM). PMID:16782327

  9. Release of single cells from the colonial oil-producing alga Botryococcus braunii by chemical treatments.

    PubMed

    Hou, Liyuan; Park, Hyunsun; Okada, Shigeru; Ohama, Takeshi

    2014-01-01

    We tested for chemical reagents that would be useful in preparing a large number of vital single cells from colonial Botryococcus braunii B-race, variety Showa. Among the 18 reagents assayed, glycerol and erythritol showed the highest potency for releasing single cells. Incubation in medium containing these reagents released 40-50 % single cells in 15 min. Fluorescent staining with Nile red revealed that except for the cap-like structures the released single cells were free of hydrocarbon oils that accumulated in the extracellular matrix where the single cells were embedded. However, to maintain the prepared single cells in vital condition, they must be maintained at a high concentration (>2?×?10(7) cells/ml); at low concentrations, they rapidly lost chlorophyll and get disrupted. In contrast to the above results obtained using B-race, Showa, single cells prepared from A-race varieties survived even at low cell concentrations. PMID:23943006

  10. Micronutrient requirements for growth and hydrocarbon production in the oil producing green alga Botryococcus braunii (Chlorophyta).

    PubMed

    Song, Liang; Qin, Jian G; Su, Shengqi; Xu, Jianhe; Clarke, Stephen; Shan, Yichu

    2012-01-01

    The requirements of micronutrients for biomass and hydrocarbon production in Botryococcus braunii UTEX 572 were studied using response surface methodology. The concentrations of four micronutrients (iron, manganese, molybdenum, and nickel) were manipulated to achieve the best performance of B. braunii in laboratory conditions. The responses of algal biomass and hydrocarbon to the concentration variations of the four micronutrients were estimated by a second order quadratic regression model. Genetic algorithm calculations showed that the optimal level of micronutrients for algal biomass were 0.266 µM iron, 0.707 µM manganese, 0.624 µM molybdenum and 3.38 µM nickel. The maximum hydrocarbon content could be achieved when the culture media contained 10.43 µM iron, 6.53 µM manganese, 0.012 µM molybdenum and 1.73 µM nickel. The validation through an independent test in a photobioreactor suggests that the modified media with optimised concentrations of trace elements can increase algal biomass by 34.5% and hydrocarbon by 27.4%. This study indicates that micronutrients play significant roles in regulating algal growth and hydrocarbon production, and the response surface methodology can be used to optimise the composition of culture medium in algal culture. PMID:22848502

  11. Micronutrient Requirements for Growth and Hydrocarbon Production in the Oil Producing Green Alga Botryococcus braunii (Chlorophyta)

    PubMed Central

    Song, Liang; Qin, Jian G.; Su, Shengqi; Xu, Jianhe; Clarke, Stephen; Shan, Yichu

    2012-01-01

    The requirements of micronutrients for biomass and hydrocarbon production in Botryococcus braunii UTEX 572 were studied using response surface methodology. The concentrations of four micronutrients (iron, manganese, molybdenum, and nickel) were manipulated to achieve the best performance of B. braunii in laboratory conditions. The responses of algal biomass and hydrocarbon to the concentration variations of the four micronutrients were estimated by a second order quadratic regression model. Genetic algorithm calculations showed that the optimal level of micronutrients for algal biomass were 0.266 µM iron, 0.707 µM manganese, 0.624 µM molybdenum and 3.38 µM nickel. The maximum hydrocarbon content could be achieved when the culture media contained 10.43 µM iron, 6.53 µM manganese, 0.012 µM molybdenum and 1.73 µM nickel. The validation through an independent test in a photobioreactor suggests that the modified media with optimised concentrations of trace elements can increase algal biomass by 34.5% and hydrocarbon by 27.4%. This study indicates that micronutrients play significant roles in regulating algal growth and hydrocarbon production, and the response surface methodology can be used to optimise the composition of culture medium in algal culture. PMID:22848502

  12. Preservation of proteinaceous material during the degradation of the green alga Botryococcus braunii: A solid-state 2D 15N 13C NMR spectroscopy study

    Microsoft Academic Search

    Xu Zang; Reno T. Nguyen; H. Rodger Harvey; Heike Knicker; Patrick G. Hatcher

    2001-01-01

    Using solid-state cross-polarization-magic-angle-spinning (CPMAS) 13C and 15N nuclear magnetic resonance (NMR) and 2-D double cross polarization (DCP) MAS 15N 13C NMR techniques, microbially degraded Botryococcus braunii was analyzed to study the chemical nature of organic nitrogen in the algal residue. The amide linkage, as found in protein, was observed as the major nitrogen component in 201-day-old degraded algae. No significant

  13. Colony organization in the green alga Botryococcus braunii (Race B) is specified by a complex extracellular matrix.

    PubMed

    Weiss, Taylor L; Roth, Robyn; Goodson, Carrie; Vitha, Stanislav; Black, Ian; Azadi, Parastoo; Rusch, Jannette; Holzenburg, Andreas; Devarenne, Timothy P; Goodenough, Ursula

    2012-12-01

    Botryococcus braunii is a colonial green alga whose cells associate via a complex extracellular matrix (ECM) and produce prodigious amounts of liquid hydrocarbons that can be readily converted into conventional combustion engine fuels. We used quick-freeze deep-etch electron microscopy and biochemical/histochemical analysis to elucidate many new features of B. braunii cell/colony organization and composition. Intracellular lipid bodies associate with the chloroplast and endoplasmic reticulum (ER) but show no evidence of being secreted. The ER displays striking fenestrations and forms a continuous subcortical system in direct contact with the cell membrane. The ECM has three distinct components. (i) Each cell is surrounded by a fibrous ?-1, 4- and/or ?-1, 3-glucan-containing cell wall. (ii) The intracolonial ECM space is filled with a cross-linked hydrocarbon network permeated with liquid hydrocarbons. (iii) Colonies are enclosed in a retaining wall festooned with a fibrillar sheath dominated by arabinose-galactose polysaccharides, which sequesters ECM liquid hydrocarbons. Each cell apex associates with the retaining wall and contributes to its synthesis. Retaining-wall domains also form "drapes" between cells, with some folding in on themselves and penetrating the hydrocarbon interior of a mother colony, partitioning it into daughter colonies. We propose that retaining-wall components are synthesized in the apical Golgi apparatus, delivered to apical ER fenestrations, and assembled on the surfaces of apical cell walls, where a proteinaceous granular layer apparently participates in fibril morphogenesis. We further propose that hydrocarbons are produced by the nonapical ER, directly delivered to the contiguous cell membrane, and pass across the nonapical cell wall into the hydrocarbon-based ECM. PMID:22941913

  14. A comparative study of macromolecular substances of a Coorongite and cell walls of the extant alga Botryococcus braunii

    Microsoft Academic Search

    Jean-Pierre L. A. Gatellier; Jan W. de Leeuw; Jaap S. Sinninghe Damsté; Sylvie Derenne; Claude Largeau; Pierre Metzger

    1993-01-01

    A Coorongite sample of Lake Balkash (Kazakhstan, CIS) was analyzed in detail by 13 C-NMR, FTIR, Curie point pyrolysis--gas chromatography--mass spectrometry, and by fractionation and derivatization with dimethyldisulphide of an off-line pyrolysate. Both the spectroscopic and the pyrolysis data indicate that the Coorongite was derived almost entirely of organic matter of the green microalga Botryococcus braunii race A. Homologous series

  15. Preservation of proteinaceous material during the degradation of the green alga Botryococcus braunii: A solid-state 2D 15N 13C NMR spectroscopy study

    NASA Astrophysics Data System (ADS)

    Zang, Xu; Nguyen, Reno T.; Harvey, H. Rodger; Knicker, Heike; Hatcher, Patrick G.

    2001-10-01

    Using solid-state cross-polarization-magic-angle-spinning (CPMAS) 13C and 15N nuclear magnetic resonance (NMR) and 2-D double cross polarization (DCP) MAS 15N 13C NMR techniques, microbially degraded Botryococcus braunii was analyzed to study the chemical nature of organic nitrogen in the algal residue. The amide linkage, as found in protein, was observed as the major nitrogen component in 201-day-old degraded algae. No significant amount of heterocyclic nitrogen, or evidence for melanoidin products, was found. The results strongly suggest that proteinaceous material can survive early diagenesis and be preserved via its encapsulation by refractory, macromolecular, organic matter.

  16. A comparative study of macromolecular substances of a Coorongite and cell walls of the extant alga Botryococcus braunii

    NASA Astrophysics Data System (ADS)

    Gatellier, Jean-Pierre L. A.; de Leeuw, Jan W.; Sinninghe Damsté, Jaap S.; Derenne, Sylvie; Largeau, Claude; Metzger, Pierre

    1993-05-01

    A Coorongite sample of Lake Balkash (Kazakhstan, CIS) was analyzed in detail by 13C-NMR, FTIR, Curie point pyrolysis—gas chromatography—mass spectrometry, and by fractionation and derivatization with dimethyldisulphide of an off-line pyrolysate. Both the spectroscopic and the pyrolysis data indicate that the Coorongite was derived almost entirely of organic matter of the green microalga Botryococcus braunii race A. Homologous series of n-alkanes and n-alk-1-en- ?9 in all pyrolysates indicated the presence of algaenan, a highly aliphatic and resistant cell wall biomacromolecule of B. Braunii race A. Highly specific pyrolysis products, in particular n-alkadienes, n-alkatrienes, alk-1-en- ?9-ones, and alk-1-en- ?10-ones with C 27, C 29, and C 31 carbon atoms clearly indicated that C 27, C 29, and C 31 alkadienes and alkatrienes, originally present in B. braunii race A as such, were cross-linked by oxygen during the very early stages of diagenesis under oxic conditions. Furthermore, several types of dialkenylethers, also present as soluble lipids in B. braunii race A, had undergone cross-linking by oxygen as well. These cross-linked lipids contribute significantly to the Coorongite and clearly demonstrate that under specific conditions kerogen consists of both preserved biomacromolecules and insoluble, cross-linked, low-molecular-weight lipids.

  17. Molecular and Biochemical Characterization of Hydrocarbon Production in the Green Microalga Botryococcus braunii 

    E-print Network

    Weiss, Taylor Leigh

    2012-10-19

    with the ability to bioremediate waste water pollutants is especially important given growing world demand for freshwater (Chisti 2010). Similarly, since algae growth can be greatly increased by the addition of CO2, algae may ____________ This dissertation... Algae biofuels ................................................................................ 1 Algae .............................................................................................. 2 Botryococcus braunii...

  18. Preservation via macromolecular associations during Botryococcus braunii decay: proteins in the Pula Kerogen

    Microsoft Academic Search

    Reno T. Nguyen; H. Rodger Harvey

    2003-01-01

    The green alga Botryococcus braunii was degraded for 201 days under oxic conditions in a flow-through system to test whether the macromolecular algaenan surrounding cells could protect proteins from rapid degradation. Protein loss was ?8× slower for B. braunii than for other previously studied phytoplankton, with base extraction consistently removing only a small fraction (<35%) of the total proteinaceous material

  19. Cultivation of green alga Botryococcus braunii in raceway, circular ponds under outdoor conditions and its growth, hydrocarbon production.

    PubMed

    Ranga Rao, A; Ravishankar, G A; Sarada, R

    2012-11-01

    The present study focused on cultivation, seasonal variation in growth, hydrocarbon production, fatty acids profiles of Botryococcus braunii (LB-572 and N-836) in raceway & circular ponds under outdoor conditions. After 18days of cultivation the biomass yield and hydrocarbon contents were increased in both raceway and circular ponds. The fat content was found to be around 24% (w/w) with palmitic and oleic acids as prominent fatty acids. Hydrocarbons of C(20)-C(30) carbon chain length were higher in raceway and circular ponds. Maximum biomass yield (2gL(-1)) and hydrocarbon content (28%) were observed in Nov-Dec. In case of B. braunii (N-836) after 25days of cultivation the biomass yield was 1gL(-1) and hydrocarbon content was 27%. Supplementation of 0.1% NaHCO(3) in the medium resulted in biomass yield of 1.5gL(-1) and hydrocarbon content of 30% compared to control. PMID:22940364

  20. Wavelength specificity of growth, photosynthesis, and hydrocarbon production in the oil-producing green alga Botryococcus braunii.

    PubMed

    Baba, Masato; Kikuta, Fumie; Suzuki, Iwane; Watanabe, Makoto M; Shiraiwa, Yoshihiro

    2012-04-01

    The effect of monochromatic light on growth, photosynthesis, and hydrocarbon production was tested in Botryococcus braunii Bot-144 (race B), which produces triterpenoid hydrocarbons. The growth was higher in order of red, blue, and green light. The color of red light-grown cells became more orange-yellow and their shape dominantly changed to grape-like with long branches. Photosynthetic carbon fixation activity was higher in order of blue, red, and green light-grown cells, but photosystem activities showed no difference. In the pulse-chase experiments with (14)CO(2), no major difference was observed in the production of lipids, hydrocarbons, polysaccharides, or proteins among the three kinds of cells, although hydrocarbon production was slightly lower in green light-grown cells. These results indicate that blue and red light were more effective for growth, photosynthetic CO(2) fixation, and hydrocarbon production than green light, and that red light is the most efficient light source when calculated based on photoenergy supplied. PMID:21683581

  1. Bio-crude transcriptomics: Gene discovery and metabolic network reconstruction for the biosynthesis of the terpenome of the hydrocarbon oil-producing green alga, Botryococcus braunii race B (Showa)

    DOE PAGESBeta

    Molnár, István [Univ. of Arizona, Tucson, AZ (United States). Natural Products Center and Bio5 Institute; Lopez, David [Univ. of California, Los Angeles, CA (United States). Dept. of Molecular, Cell and Developmental Biology; Wisecaver, Jennifer H. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Ecology and Evolutionary Biology; Devarenne, Timothy P. [Texas A & M Univ., College Station, TX (United States). Dept. of Biochemistry and Biophysics; Weiss, Taylor L. [Texas A & M Univ., College Station, TX (United States). Dept. of Biochemistry and Biophysics; Pellegrini, Matteo [Univ. of California, Los Angeles, CA (United States). Dept. of Molecular, Cell and Developmental Biology; Hackett, Jeremiah D. [Univ. of Arizona, Tucson, AZ (United States). Bio5 Institute and Dept. of Ecology and Evolutionary Biology

    2012-01-01

    Microalgae hold promise for yielding a biofuel feedstock that is sustainable, carbon-neutral, distributed, and only minimally disruptive for the production of food and feed by traditional agriculture. Amongst oleaginous eukaryotic algae, the B race of Botryococcus braunii is unique in that it produces large amounts of liquid hydrocarbons of terpenoid origin. These are comparable to fossil crude oil, and are sequestered outside the cells in a communal extracellular polymeric matrix material. Biosynthetic engineering of terpenoid bio-crude production requires identification of genes and reconstruction of metabolic pathways responsible for production of both hydrocarbons and other metabolites of the alga that compete for photosynthetic carbon and energy.

  2. Bio-crude transcriptomics: Gene discovery and metabolic network reconstruction for the biosynthesis of the terpenome of the hydrocarbon oil-producing green alga, Botryococcus braunii race B (Showa)

    DOE PAGESBeta

    Molnár, István; Lopez, David; Wisecaver, Jennifer H.; Devarenne, Timothy P.; Weiss, Taylor L.; Pellegrini, Matteo; Hackett, Jeremiah D.

    2012-01-01

    Microalgae hold promise for yielding a biofuel feedstock that is sustainable, carbon-neutral, distributed, and only minimally disruptive for the production of food and feed by traditional agriculture. Amongst oleaginous eukaryotic algae, the B race of Botryococcus braunii is unique in that it produces large amounts of liquid hydrocarbons of terpenoid origin. These are comparable to fossil crude oil, and are sequestered outside the cells in a communal extracellular polymeric matrix material. Biosynthetic engineering of terpenoid bio-crude production requires identification of genes and reconstruction of metabolic pathways responsible for production of both hydrocarbons and other metabolites of the alga that competemore »for photosynthetic carbon and energy.« less

  3. Effects of carbon source on growth and morphology of Botryococcus braunii

    Microsoft Academic Search

    Takako Tanoi; Masanobu Kawachi; Makoto M. Watanabe

    2011-01-01

    The green colonial alga Botryococcus braunii is characterized by the ability to produce and accumulate large amounts of hydrocarbons. We isolated and established an axenic\\u000a clonal strain of B. braunii B70 and investigated the effects of organic carbon sources, including glucose, mannose, fructose, galactose, or acetate,\\u000a on growth under light and dark conditions. This algal strain had the capacity to

  4. Macrocyclic alkanes in crude oils from the algaenan of Botryococcus braunii

    Microsoft Academic Search

    Michiele Audino; Kliti Grice; Robert Alexander; Robert I. Kagi

    2002-01-01

    New classes of biomarkers, macrocyclic alkanes, have been previously identified in high grade oil shales (torbanites, Late Carboniferous-Late Permian) containing remains of the freshwater alga Botryococcus braunii (B. braunii). In this study we report the occurrence of these compounds in two Indonesian crude oils (Minas and Duri, Tertiary) utilising metastable reaction monitoring GC–MS experiments. Based on ?13C data and the

  5. Hydrocarbon fuels from solar energy via the alga Botryococcus brauni

    Microsoft Academic Search

    L. W. Hillen; D. R. Warren

    1976-01-01

    The production of liquid hydrocarbon fuels from a non-depleting source such as solar energy and algae is investigated. The alga Botryococcus braunii, which grows widely in nature, can produce hydrocarbons in amounts up to 75% of its dry mass. There is considerable contemporary and geological evidence, especially in Australia, that it is capable of prolific growth under appropriate conditions. Harvesting

  6. Botryococcus braunii : a rich source for hydrocarbons and related ether lipids

    Microsoft Academic Search

    P. Metzger; C. Largeau

    2005-01-01

    This paper presents a review on Botryococcus braunii, a cosmopolitan green colonial microalga characterised by a considerable production of lipids, notably hydrocarbons. Strains like wild populations of this alga differ in the type of hydrocarbons they synthesise and accumulate: (1) n-alkadienes and trienes, (2) triterpenoid botryococcenes and methylated squalenes, or (3) a tetraterpenoid, lycopadiene. In addition to hydrocarbons and some

  7. Isolation of herbicide-resistant mutants of Botryococcus braunii.

    PubMed

    Ioki, Motohide; Ohkoshi, Masahiro; Nakajima, Nobuyoshi; Nakahira-Yanaka, Yuka; Watanabe, Makoto M

    2012-04-01

    Aiming at herbicide-assisted cultivation of Botryococcus braunii for prevention of algal contamination, herbicide-tolerant mutant lines of B. braunii were established for two widely used herbicides, methyl viologen and glufosinate. Some established mutant lines exhibited vigorous oil production and growth in herbicide-containing media. Because the two herbicides were effective in controlling the growth of the algal competitors of B. braunii, these mutants can be directly used in industrial attempts for cost-effective oil production in herbicide-assisted non-axenic systems. This is the first report of mutagenesis of B. braunii. PMID:21906932

  8. Extraction of hydrocarbons from microalga Botryococcus braunii with switchable solvents.

    PubMed

    Samorì, Chiara; Torri, Cristian; Samorì, Giulia; Fabbri, Daniele; Galletti, Paola; Guerrini, Franca; Pistocchi, Rossella; Tagliavini, Emilio

    2010-05-01

    Lipid extraction is a critical step in the development of biofuels from microalgae. Here a new procedure was proposed to extract hydrocarbons from dried and water-suspended samples of the microalga Botryococcus braunii by using switchable-polarity solvents (SPS) based on 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU) and an alcohol. The high affinity of the non-ionic form of DBU/alcohol SPS towards non-polar compounds was exploited to extract hydrocarbons from algae, while the ionic character of the DBU-alkyl carbonate form, obtained by the addition of CO(2), was used to recover hydrocarbons from the SPS. DBU/octanol and DBU/ethanol SPS were tested for the extraction efficiency of lipids from freeze-dried B. braunii samples and compared with n-hexane and chloroform/methanol. The DBU/octanol system was further evaluated for the extraction of hydrocarbons directly from algal culture samples. DBU/octanol exhibited the highest yields of extracted hydrocarbons from both freeze-dried and liquid algal samples (16% and 8.2% respectively against 7.8% and 5.6% with n-hexane). PMID:20071168

  9. Polyacetals based on polymethylsqualene diols, precursors of algaenan in Botryococcus braunii race B

    Microsoft Academic Search

    Pierre Metzger; Marie-Noëlle Rager; Claude Largeau

    2007-01-01

    Aliphatic polyacetals comprising polymethylsqualene diol moieties were isolated from the heptane extracts of two strains of the green alga Botryococcus braunii race B. Size exclusion chromatography showed the isolates to have masses in the range 1.2×104 to 4×106Daltons. Pulse-field gradient NMR analysis allowed the spectroscopic resolution of a crude algal extract into polyacetals, demonstrating that these polymers are not artifacts

  10. Aerated swine lagoon wastewater: a promising alternative medium for Botryococcus braunii cultivation in open system.

    PubMed

    Liu, Junzhi; Ge, Yaming; Cheng, Haixiang; Wu, Lianghuan; Tian, Guangming

    2013-07-01

    To understand the potential of using swine lagoon wastewater to cultivate Botryococcus braunii for biofuel production, growth characteristics of B. braunii 765 cultivated in aerated swine lagoon wastewater (ASLW) without sterilization and pH adjustment were investigated. The results showed that the alga strain could maintain competitive advantage over the 26-day cultivation. The highest dry biomass of alga grown in ASLW was 0.94 mg L(-1) at day 24, which was 1.73 times that grown in BG11 medium, an artificial medium normally used for B. braunii cultivation. And the algal hydrocarbon content was 23.8%, being more than twice that in BG11 medium. Additionally, after the 26-day cultivation, about 40.8% of TN and 93.3% of TP in ASLW were removed, indicating also good environmental benefits of algal bioremediation. PMID:23660382

  11. Early diagenesis of Botryococcus braunii race A as determined by high resolution magic angle spinning (HRMAS) NMR

    Microsoft Academic Search

    Isaiah D. Ruhl; Elodie Salmon; Patrick G. Hatcher

    2011-01-01

    An algal culture of Botryococcus braunii race A and its residue obtained after 201days of oxic biodegradation are characterized using high resolution magic angle spinning (HRMAS) NMR spectroscopy, a hybrid technique which provides molecular details non-invasively. The high resolution of two dimensional NMR using HRMAS gives precise structural assignments of different classes of compounds contained in the initial algae and

  12. Radiation characteristics of Botryococcus braunii, Chlorococcum littorale, and Chlorella sp. used for CO 2 fixation and biofuel production

    Microsoft Academic Search

    Halil Berberoglu; Pedro S. Gomez; Laurent Pilon

    2009-01-01

    This paper reports experimental measurements of the radiation characteristics of green algae used for carbon dioxide fixation via photosynthesis. The generated biomass can be used to produce not only biofuels but also feed for animal and food supplements for human consumptions. Particular attention was paid to three widely used species namely Botryococcus braunii, Chlorella sp., and Chlorococcum littorale. Their extinction

  13. Functional Identification of Triterpene Methyltransferases from Botryococcus braunii Race B*

    PubMed Central

    Niehaus, Tom D.; Kinison, Scott; Okada, Shigeru; Yeo, Yun-soo; Bell, Stephen A.; Cui, Ping; Devarenne, Timothy P.; Chappell, Joe

    2012-01-01

    Botryococcus braunii race B is a colony-forming, green algae that accumulates triterpene oils in excess of 30% of its dry weight. The composition of the triterpene oils is dominated by dimethylated to tetramethylated forms of botryococcene and squalene. Although unusual mechanisms for the biosynthesis of botryococcene and squalene were recently described, the enzyme(s) responsible for decorating these triterpene scaffolds with methyl substituents were unknown. A transcriptome of B. braunii was screened computationally assuming that the triterpene methyltransferases (TMTs) might resemble the S-adenosyl methionine-dependent enzymes described for methylating the side chain of sterols. Six sterol methyltransferase-like genes were isolated and functionally characterized. Three of these genes when co-expressed in yeast with complementary squalene synthase or botryococcene synthase expression cassettes resulted in the accumulation of mono- and dimethylated forms of both triterpene scaffolds. Surprisingly, TMT-1 and TMT-2 exhibited preference for squalene as the methyl acceptor substrate, whereas TMT-3 showed a striking preference for botryococcene as its methyl acceptor substrate. These in vivo preferences were confirmed with in vitro assays utilizing microsomal preparations from yeast overexpressing the respective genes, which encode for membrane-associated enzymes. Structural examination of the in vivo yeast generated mono- and dimethylated products by NMR identified terminal carbons, C-3 and C-22/C-20, as the atomic acceptor sites for the methyl additions to squalene and botryococcene, respectively. These sites are identical to those previously reported for the triterpenes extracted from the algae. The availability of closely related triterpene methyltransferases exhibiting distinct substrate selectivity and successive catalytic activities provides important tools for investigating the molecular mechanisms responsible for the specificities exhibited by these unique enzymes. PMID:22241476

  14. Functional identification of triterpene methyltransferases from Botryococcus braunii race B.

    PubMed

    Niehaus, Tom D; Kinison, Scott; Okada, Shigeru; Yeo, Yun-soo; Bell, Stephen A; Cui, Ping; Devarenne, Timothy P; Chappell, Joe

    2012-03-01

    Botryococcus braunii race B is a colony-forming, green algae that accumulates triterpene oils in excess of 30% of its dry weight. The composition of the triterpene oils is dominated by dimethylated to tetramethylated forms of botryococcene and squalene. Although unusual mechanisms for the biosynthesis of botryococcene and squalene were recently described, the enzyme(s) responsible for decorating these triterpene scaffolds with methyl substituents were unknown. A transcriptome of B. braunii was screened computationally assuming that the triterpene methyltransferases (TMTs) might resemble the S-adenosyl methionine-dependent enzymes described for methylating the side chain of sterols. Six sterol methyltransferase-like genes were isolated and functionally characterized. Three of these genes when co-expressed in yeast with complementary squalene synthase or botryococcene synthase expression cassettes resulted in the accumulation of mono- and dimethylated forms of both triterpene scaffolds. Surprisingly, TMT-1 and TMT-2 exhibited preference for squalene as the methyl acceptor substrate, whereas TMT-3 showed a striking preference for botryococcene as its methyl acceptor substrate. These in vivo preferences were confirmed with in vitro assays utilizing microsomal preparations from yeast overexpressing the respective genes, which encode for membrane-associated enzymes. Structural examination of the in vivo yeast generated mono- and dimethylated products by NMR identified terminal carbons, C-3 and C-22/C-20, as the atomic acceptor sites for the methyl additions to squalene and botryococcene, respectively. These sites are identical to those previously reported for the triterpenes extracted from the algae. The availability of closely related triterpene methyltransferases exhibiting distinct substrate selectivity and successive catalytic activities provides important tools for investigating the molecular mechanisms responsible for the specificities exhibited by these unique enzymes. PMID:22241476

  15. Culture of the green microalga Botryococcus braunii Showa with LED irradiation eliminating violet light enhances hydrocarbon production and recovery.

    PubMed

    Atobe, Sueko; Saga, Kiyotaka; Maeyama, Haruko; Fujiwara, Kazuhiro; Okada, Shigeru; Imou, Kenji

    2014-10-01

    The green microalga Botryococcus braunii (B. braunii), race B, was cultured under light-emitting diode (LED) irradiation with and without violet light. This study examined the effect of violet light on hydrocarbon recovery and production in B. braunii. C34 botryococcene hydrocarbons were efficiently extracted by thermal pretreatments at lower temperatures when the alga was cultured without violet light. The hydrocarbon content was also higher (approximately 3%) in samples cultured without violet light. To elucidate the mechanism of effective hydrocarbon recovery and production, we examined structural components of the extracellular matrix (ECM). The amounts of extracellular carotenoids and water-soluble polymers extracted by thermal pretreatment from the ECM were decreased when the alga was cultured without violet light. These results indicate that LED irradiation without violet light is more effective for hydrocarbon recovery and production in B. braunii. Furthermore, structural ECM components are closely involved in hydrocarbon recovery and production in B. braunii. PMID:25069809

  16. Botryococcus braunii: a rich source for hydrocarbons and related ether lipids.

    PubMed

    Metzger, P; Largeau, C

    2005-02-01

    This paper presents a review on Botryococcus braunii, a cosmopolitan green colonial microalga characterised by a considerable production of lipids, notably hydrocarbons. Strains like wild populations of this alga differ in the type of hydrocarbons they synthesise and accumulate: (1) n-alkadienes and trienes, (2) triterpenoid botryococcenes and methylated squalenes, or (3) a tetraterpenoid, lycopadiene. In addition to hydrocarbons and some classic lipids, these algae produce numerous series of characteristic ether lipids closely related to hydrocarbons. This review covers the algal biodiversity, the chemical structures and biosynthesis of hydrocarbons and ether lipids and the biotechnological studies related to hydrocarbon production. PMID:15630516

  17. Antioxidant activity of Botryococcus braunii extract elucidated in vitro models.

    PubMed

    Rao, Ambati Ranga; Sarada, Ravi; Baskaran, Vallikannan; Ravishankar, Gokare Aswathanarayana

    2006-06-28

    Botryococcus braunii is a green colonial microalga that is used mainly for the production of hydrocarbons, exopolysaccharides, and carotenoids. In the present study, the antioxidant properties of acetone extracts of B. braunii were evaluated using in vitro model systems such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxy radical scavenging, and lipid peroxidation in human low-density lipoprotein and rat tissues. Acetone extracts of B. braunii (equivalent to 10 ppm total carotenoid) exhibited 71 and 67% antioxidant activity in DPPH and hydroxyl radical scavenging model systems, respectively. Similarly, the extract also showed 72, 71, and 70% antioxidant activity in the liver, brain, and kidney of rats. Low-density lipoprotein oxidation induced by Cu2+ ions was also protected (22, 38, and 51%) by the algal extract in a dose-dependent manner (4, 6, and 8 ppm levels of total carotenoid). Thiobarbituric acid reactive substances concentration in the blood, liver, and kidney of rats was also significantly decreased in B. braunii treated samples compared with those of control. Carotenoids (violaxanthin, astaxanthin, lutein, zeaxanthin, chlorophylls a and b, and alpha, beta-carotene) identified in the B. braunii acetone extract may be exhibiting antioxidant activity. Among the carotenoids, lutein represents more than 75% of the total carotenoids. B. braunii extract was shown to be effective for protecting biological systems against various oxidative stresses in vitro. This is the first report on the antioxidant properties of B. braunii. PMID:16787003

  18. Desiccation tolerance of Botryococcus braunii (Trebouxiophyceae, Chlorophyta) and extreme temperature tolerance of dehydrated cells.

    PubMed

    Demura, Mikihide; Ioki, Motohide; Kawachi, Masanobu; Nakajima, Nobuyoshi; Watanabe, Makoto M

    2014-01-01

    Botryococcus braunii Kützing, a green colonial microalga, occurs worldwide in both freshwater and brackish water environments. Despite considerable attention to B. braunii as a potential source of renewable fuel, many ecophysiological properties of this alga remain unknown. Here, we examined the desiccation and temperature tolerances of B. braunii using two newly isolated strains BOD-NG17 and BOD-GJ2. Both strains survived through 6- and 8-month desiccation treatments but not through a 12-month treatment. Interestingly, the desiccation-treated cells of B. braunii gained tolerance to extreme temperature shifts, i.e., high temperature (40 °C) and freezing (-20 °C). Both strains survived for at least 4 and 10 days at 40 and -20 °C, respectively, while the untreated cells barely survived at these temperatures. These traits would enable long-distance dispersal of B. braunii cells and may account for the worldwide distribution of this algal species. Extracellular substances such as polysaccharides and hydrocarbons seem to confer the desiccation tolerance. PMID:24600162

  19. Interactions of Botryococcus braunii cultures with bacterial biofilms.

    PubMed

    Rivas, Mariella O; Vargas, Pedro; Riquelme, Carlos E

    2010-10-01

    Unicellular microalgae generally grow in the presence of bacteria, particularly when they are farmed massively. This study analyzes the bacteria associated with mass culture of Botryococcus braunii: both the planktonic bacteria in the water column and those forming biofilms adhered to the surface of the microalgal cells (?10?-10? culturable cells per gram microalgae). Furthermore, we identified the culturable bacteria forming a biofilm in the microalgal cells by 16S rDNA sequencing. At least eight different culturable species of bacteria were detected in the biofilm and were evaluated for the presence of quorum-sensing signals in these bacteria. Few studies have considered the implications of this phenomenon as regards the interaction between bacteria and microalgae. Production of C4-AHL and C6-AHL were detected in two species, Pseudomonas sp. and Rhizobium sp., which are present in the bacterial biofilm associated with B. braunii. This type of signal was not detected in the planktonic bacteria isolated from the water. We also noted that the bacterium, Rhizobium sp., acted as a probiotic bacterium and significantly encouraged the growth of B. braunii. A direct application of these beneficial bacteria associated with B. braunii could be, to use them like inoculants for large-scale microalgal cultures. They could optimize biomass production by enhancing growth, particularly in this microalga that has a low growth rate. PMID:20502890

  20. Influence of CO2 on growth and hydrocarbon production in Botryococcus braunii.

    PubMed

    Ranga Rao, A; Sarada, R; Ravishankar, G A

    2007-03-01

    Botryococcus braunii is a green colonial fresh water microalga and it is recognized as one of the renewable resources for production of liquid hydrocarbons. CFTRI-Bb-1 and CFTRI-Bb-2 have been reported for the first time and their performance with regard to growth and biochemical profile is presented here. The present study focused on effect of carbon dioxide (CO2) on biomass, hydrocarbon, carbohydrate production, fatty acid profile, and carotenoid content in various species of B. braunii (LB-572, SAG 30.81, MCRC-Bb, N-836, CFTRI-Bb-1, and CFTRI-Bb-2) at 0.5, 1.0, and 2.0% (v/v) levels using a two-tier flask. CO2 at 2.0% (v/v) level enhanced growth of the organism, and a two-fold increase in biomass and carotenoid contents was observed in all the B. braunii strains studied compared with control culture (without CO2 supplementation). At 1% and 2% (v/v) CO2 concentrations, palmitic acid and oleic acid levels increased by 2.5 to 3 folds in one of the strains of B. braunii (LB-572). Hydrocarbon content was found to be above 20% at 2% CO2 level in the B. braunii LB-572, CFTRI-Bb-2, CFTRI-Bb-1, and N-836 strains, whereas it was less than 20% in the SAG 30.81 and MCRC-Bb strains compared with control culture. This culture methodology will provide information on CO2 requirement for growth of algae and metabolite production. B. braunii spp. can be grown at the tested levels of CO2 concentration without much influence on culture pH. PMID:18050944

  1. Identification of unique mechanisms for triterpene biosynthesis in Botryococcus braunii.

    PubMed

    Niehaus, Tom D; Okada, Shigeru; Devarenne, Timothy P; Watt, David S; Sviripa, Vitaliy; Chappell, Joe

    2011-07-26

    Botryococcene biosynthesis is thought to resemble that of squalene, a metabolite essential for sterol metabolism in all eukaryotes. Squalene arises from an initial condensation of two molecules of farnesyl diphosphate (FPP) to form presqualene diphosphate (PSPP), which then undergoes a reductive rearrangement to form squalene. In principle, botryococcene could arise from an alternative rearrangement of the presqualene intermediate. Because of these proposed similarities, we predicted that a botryococcene synthase would resemble squalene synthase and hence isolated squalene synthase-like genes from Botryococcus braunii race B. While B. braunii does harbor at least one typical squalene synthase, none of the other three squalene synthase-like (SSL) genes encodes for botryococcene biosynthesis directly. SSL-1 catalyzes the biosynthesis of PSPP and SSL-2 the biosynthesis of bisfarnesyl ether, while SSL-3 does not appear able to directly utilize FPP as a substrate. However, when combinations of the synthase-like enzymes were mixed together, in vivo and in vitro, robust botryococcene (SSL-1+SSL-3) or squalene biosynthesis (SSL1+SSL-2) was observed. These findings were unexpected because squalene synthase, an ancient and likely progenitor to the other Botryococcus triterpene synthases, catalyzes a two-step reaction within a single enzyme unit without intermediate release, yet in B. braunii, these activities appear to have separated and evolved interdependently for specialized triterpene oil production greater than 500 MYA. Coexpression of the SSL-1 and SSL-3 genes in different configurations, as independent genes, as gene fusions, or targeted to intracellular membranes, also demonstrate the potential for engineering even greater efficiencies of botryococcene biosynthesis. PMID:21746901

  2. [Improved fluorescence spectrometric determination of lipid content in Botryococcus braunii].

    PubMed

    Liu, Xinying; Wang, Zhiping; Yu, Jinxin; Lü, Beifen; Ma, Lifang; Chen, Ziyuan

    2013-03-01

    Botryococcus braunii is a unique colonial green microalga and a great potential renewable resource of liquid fuel because of its ability to produce lipids. Due to the dense cell colonies and rigidly thick cell wall of B. braunii, the traditional Nile red method is usually of low sensitivity and bad repeatability and hard for the determination of lipid content in the cells. By dispersing the colony with ultrasonic, assisting permeation of Nile red across the cell wall with dimethyl sulfoxide and optimizing the staining conditions, we established an improved detection method. The details were as follows: after the colonial algal sample was treated by ultrasonic at 20 kHz for 20 s, 100 W transmitting power and with 1 s on/1 s off intermittent cycle, the equivoluminal 15% (V/V) dimethyl sulfoxide and 3 microg/mL Nile red were successively added and mixed evenly, then the staining system was incubated in dark at 40 degrees C for 10 min, and subsequently was measured by fluorescence spectroscopy detection with an excitation wavelength of 490 nm. Compared with the traditional method, the improved one not only had higher detection sensitivity which was increased by 196.6%, but also had obviously better detection repeatability whose characteristic parameter - relative standard deviation (RSD) was decreased from 10.91% to 1.84%. Therefore, the improved method could provide a rapid and sensitive detection of lipid content for B. braunii breeding and cultivation. PMID:23789279

  3. Bio-harvesting and pyrolysis of the microalgae Botryococcus braunii.

    PubMed

    Al-Hothaly, Khalid A; Adetutu, Eric M; Taha, Mohamed; Fabbri, Daniele; Lorenzetti, Chiara; Conti, Roberto; May, Brian H; Shar, Sahar S; Bayoumi, Reda A; Ball, Andrew S

    2015-09-01

    The microalgae Botryococcus braunii is widely recognized as a potentially important biofuel-feedstock whose commercial exploitation is limited by difficulties with its cultivation and harvesting. In this study, two B. braunii strains, Kossou-4 and Overjuyo-3 were successfully cultured at a 500l-scale for 60-days. Harvesting by bio-flocculation with Aspergillus fumigatus at an optimum ratio of 1:40 of fungus to microalgal culture resulted in up to 98% recovery of biomass in the two strains. Ultimate analysis (C, N, H, S, ash, high heating value) and pyrolysis (analytical and preparative pyrolysis and GC-MS assays) showed that co-harvesting with fungi did not cause any impairment of the feedstock value of the microalgal biomass. This work represents the first report on the successful culturing and harvesting of these strains at a 500l-scale using bio-flocculation. The use of A. fumigatus represents an efficient and economical method for the harvest of B. braunii for biofuel production. PMID:25983230

  4. The growth, lipid and hydrocarbon production of Botryococcus braunii with attached cultivation.

    PubMed

    Cheng, Pengfei; Ji, Bei; Gao, Lili; Zhang, Wei; Wang, Junfeng; Liu, Tianzhong

    2013-06-01

    The green alga Botryococcus braunii is regarded as a potential source of renewable fuel due to its high lipid and hydrocarbon contents. However, the slow growth rate damaged its feasibility for biofuel production. In this study, a novel method of 'attached cultivation' was introduced to incubate B. braunii FACHB 357 (B race). A high biomass productivity of 6.5 gm(-2)d(-1) was achieved in single layer attached system at early stage of cultivation. At day 10, the biomass, lipid and hydrocarbon productivities were 5.5, 2.34 and 1.06 gm(-2)d(-1), respectively. Under nitrogen starvation condition, both of the contents of lipid and hydrocarbon were increased, whereas the profile of hydrocarbon kept almost unchanged, while the content for oleic acid (18:1) increased and linolenic acid (18:3) decreased. With a multi-layer photobioreactor, a biomass productivity of 49.1 gm(-2)d(-1) or a photosynthetic efficiency of 14.9% (visible light) were obtained under continuous illumination of 500 ?molm(-2)s(-1). PMID:23612166

  5. Structural and isotopic analysis of kerogens in sediments rich in free sulfurised Botryococcus braunii biomarkers

    Microsoft Academic Search

    Kliti Grice; Stefan Schouten; Peter Blokker; Sylvie Derenne; Claude Largeau; Arie Nissenbaum; Jaap S. Sinninghe Damsté

    2003-01-01

    Type I kerogens of two relatively immature, unusual hypersaline sediments [with extracts rich in sulfurised Botryococcus braunii (B. braunii) biomarkers] of Miocene\\/Pliocene age from the Sdom Formation (Dead Sea, Israel), have been investigated using a variety of organic geochemical techniques. Py–GC–MS revealed a dominant homologous series of n-alk-1-enes and n-alkanes. Solid state 13C NMR and FT-IR data are consistent with

  6. Genome size and phylogenetic analysis of the A and L races of Botryococcus braunii

    Microsoft Academic Search

    Taylor L. Weiss; J. Spencer Johnston; Kazuhiro Fujisawa; Shigeru Okada; Timothy P. Devarenne

    Botryococcus braunii (Chlorophyta, Botryococcaceae) is a colony-forming green microalga that produces large amounts of liquid hydrocarbons, which\\u000a can be converted into transportation fuels. There are three different races of B. braunii, A, B, and L, that are distinguished based on the type of hydrocarbon each produces. Each race also has many strains that\\u000a are distinguished by the location from which

  7. Hydrocarbon production in high density Botryococcus braunii race B continuous culture.

    PubMed

    Khatri, Waqas; Hendrix, Robert; Niehaus, Tom; Chappell, Joe; Curtis, Wayne R

    2014-03-01

    Continuous cultures of Botryococcus braunii race B were maintained at photosynthetic cell densities as high as 20 g dry weight per liter for up to 3 months. Growth associated triterpene hydrocarbon accumulation was nearly constant at 22.5% of dry weight for a range of growth rates maintained by daily replacement of 5-15% of the respective cultures. The ability to achieve high cell concentrations and oil levels of roughly 5 g triterpene oil/L resulted from a combination of high light (? 1/4 full sun for 15 h/day) and replenishing stoichiometrically balanced growth medium. Due to light-limited growth conditions, cell concentration dropped nearly linearly with increased dilution rate. This reduction in cell number resulted in increased productivity per cell at higher dilution rates and was accompanied by a dramatic increase in algae colony size from 0.09 to 0.343 mm at high dilution rate. This change in colony size resulted in an equally dramatic change in optical density (OD) per gram dry weight, which precluded use of simple correlations of OD and cell concentration. A trickle-film photobioreactor was also demonstrated as a scalable approach to achieving these ultra-high cell concentrations. Additional media analysis revealed a steady increase in photobioreactor conductivity suggesting an accumulation of ions may be the reason for rapid culture crash and washout observed at all dilution rates after several months of continuous operation. The volumetric productivity of 22.5 mg oil/L/photo-h reported here is more than an order of magnitude higher than previous reports for B. braunii race B, reflecting the high cell densities used in this work and substantiating a higher metabolic rate for B. braunii race B than previously surmised from its relatively long doubling times. PMID:24122424

  8. A high molecular weight complex lipid, aliphatic polyaldehyde tetraterpenediol polyacetal from Botryococcus braunii (L race)

    Microsoft Academic Search

    O Bertheas; P Metzger; C Largeau

    1999-01-01

    An aliphatic polyaldehyde tetraterpenediol polyacetal (APTP) has been isolated from the heptane extract of an Ivorian strain of the L chemical race of the green microalga, Botryococcus braunii. Size exclusion HPLC showed an unimodal distribution from Mr 5000 to 4000000, with a peak at 237000. The chemical structure of this soluble high Mr polymer was determined by spectroscopic methods and

  9. Closed pyrolyses of the isoprenoid algaenan of Botryococcus braunii, L race: geochemical implications for derived kerogens

    Microsoft Academic Search

    F. Behar; S. Derenne; C. Largeau

    1995-01-01

    Algaenans, i.e., highly aliphatic, nonhydrolysable, insoluble macromolecular constituents, have been identified in a number of microalga cell walls and their selective preservation shown to play a major role in the formation of numerous kerogens. All the algaenans so far examined comprise a network of long polymethylenic chains, except for the L race of Botryococcus braunii. The resistant macromolecular material isolated

  10. Braunicetals: acetals from condensation of macrocyclic aldehydes and terpene diols in Botryococcus braunii.

    PubMed

    Metzger, Pierre; Rager, Marie-Noëlle; Fosse, Céline

    2008-09-01

    Two series of braunicetals were isolated from the green microalga Botryococcus braunii. Based on spectroscopic and chemical evidence, their structures were determined to be acetals formed by the condensation of C32 and C34 macrocyclic aldehydes with C33 and C34 methylated squalene diols (series I), or a C40 lycopaene diol (series II). PMID:18639308

  11. The single cellular green microalga Botryococcus braunii, race B possesses three distinct 1-deoxy-D-xylulose 5-phosphate synthases.

    PubMed

    Matsushima, Daisuke; Jenke-Kodama, Holger; Sato, Yohei; Fukunaga, Yusuke; Sumimoto, Koremitsu; Kuzuyama, Tomohisa; Matsunaga, Shigeki; Okada, Shigeru

    2012-04-01

    Green algae exclusively use the methylerythritol 4-phosphate (MEP) pathway for the biosynthesis of isoprenoids. The first enzyme of this pathway is 1-deoxy-D-xylulose 5-phosphate synthase (DXS, EC 2.2.1.7). Green algae have been thought to possess only a single DXS, in contrast to land plants, which have at least two isoforms that serve different roles in metabolism. The green microalga Botryococcus braunii has an extraordinary isoprenoid metabolism, as it produces large amounts of triterpene hydrocarbons. Here, we did cDNA cloning of DXSs from B. braunii and examined enzyme activities of the heterologously expressed proteins. Three distinct DXS isoforms were identified, all of which were functional and had similar kinetic properties, whereas the temperature dependence of enzyme activity showed considerable differences. Transcription of the genes was examined by real time quantitative RT-PCR. The three DXS genes were simultaneously expressed, and the expression levels were highest on day six after subculturing. B. braunii is the first green microalga demonstrated to have multiple DXS isoforms like land plants. This difference to other microalgae seems to mirror its special needs for extensive triterpene production by increasing the metabolic flow through the MEP pathway. PMID:22325894

  12. Biomarker evidence for the co-occurrence of three races (A, B and L) of Botryococcus braunii

    E-print Network

    Sachs, Julian P.

    Junco Lake, Gala´pagos Zhaohui Zhang a,*, Pierre Metzger b , Julian P. Sachs a,1 a Department of Earth In spite of the fact that individual races of Botryococcus braunii are widely distributed in lakes, reports-occurrence of three different races of B. braunii (A, B and L) in the water column and sediments of El Junco Lake

  13. Isolation and characterization of two squalene epoxidase genes from Botryococcus braunii, race B.

    PubMed

    Uchida, Hidenobu; Sumimoto, Koremitsu; Ferriols, Victor Marco Emmanuel; Imou, Kenji; Saga, Kiyotaka; Furuhashi, Kenichi; Matsunaga, Shigeki; Okada, Shigeru

    2015-01-01

    The B race of the green microalga Botryococcus braunii produces triterpene hydrocarbons, botryococcenes and methylsqualenes that can be processed into jet fuels with high heating values. In this alga, squalene is also converted into membrane sterols after 2,3-epoxidation. In the present study, cDNA clones of two distinct squalene epoxidases (BbSQE-I and -II) were isolated. Predicted amino acid sequences encoded on these genes are 45% identical with each other. Introduction of BbSQE-I or -II into Saccharomyces cerevisie erg1 mutants resulted in the complementation of ergosterol auxotrophy. The relative expression level of SQE-II increased 3.5-fold from the early stage to the middle phase of a culture period of 42 days, while that of SQE-I was almost constant throughout the culture period. Southern blot analyses suggested that these genes are single-copied genes. This is the first report on the isolation of functional SQEs that are encoded in duplicated loci in the algal genome. PMID:25830359

  14. Isolation and Characterization of Two Squalene Epoxidase Genes from Botryococcus braunii, Race B

    PubMed Central

    Uchida, Hidenobu; Sumimoto, Koremitsu; Ferriols, Victor Marco Emmanuel; Imou, Kenji; Saga, Kiyotaka; Furuhashi, Kenichi; Matsunaga, Shigeki; Okada, Shigeru

    2015-01-01

    The B race of the green microalga Botryococcus braunii produces triterpene hydrocarbons, botryococcenes and methylsqualenes that can be processed into jet fuels with high heating values. In this alga, squalene is also converted into membrane sterols after 2,3-epoxidation. In the present study, cDNA clones of two distinct squalene epoxidases (BbSQE-I and -II) were isolated. Predicted amino acid sequences encoded on these genes are 45% identical with each other. Introduction of BbSQE-I or -II into Saccharomyces cerevisie erg1 mutants resulted in the complementation of ergosterol auxotrophy. The relative expression level of SQE-II increased 3.5-fold from the early stage to the middle phase of a culture period of 42 days, while that of SQE-I was almost constant throughout the culture period. Southern blot analyses suggested that these genes are single-copied genes. This is the first report on the isolation of functional SQEs that are encoded in duplicated loci in the algal genome. PMID:25830359

  15. Mechanism of lipid extraction from Botryococcus braunii FACHB 357 in a biphasic bioreactor.

    PubMed

    Zhang, Fang; Cheng, Li-Hua; Gao, Wang-Lei; Xu, Xin-Hua; Zhang, Lin; Chen, Huan-Lin

    2011-07-20

    Algal lipid of Botryococcus braunii could be produced continuously and in situ extracted in an aqueous-organic bioreactor. In this study, the cell ultra-structure and cell membrane permeability of B. braunii FACHB 357 were investigated to understand the mechanism of lipid extraction within the biphasic system. The results showed that biocompatible solvent of tetradecane could induce algal lipid accumulation, enable the cell membrane more active and the cell wall much looser. The exocytosis process was observed to be one of the mechanisms for lipid cross-membrane extraction in the presence of organic solvent. PMID:21640768

  16. Thermal decomposition process in algaenan of Botryococcus braunii race L. Part 2: Molecular dynamics simulations using the ReaxFF reactive force field

    E-print Network

    Goddard III, William A.

    Thermal decomposition process in algaenan of Botryococcus braunii race L. Part 2: Molecular simulation results on pyrolysis of a molecular model of the algaenan Botryococcus braunii race L biopolymer cracking process within algaenan race L biopolymers. The simulations indicate that the thermal

  17. Hydrogen Isotope Fractation Between Water and Algal Lipids of Three Strains of Botryococcus braunii Under Controlled Conidtions

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Sachs, J. P.

    2004-12-01

    Understanding of precipitation anomaly variations is essential to the reconstruction of paleo-El Nino at the low latitudes. In enclosed lakes, where lake level is affected by the balance between precipitation and evaporation only, water ? D reflects precipitation patterns. Freshwater algae, which utilize lake water for photosynthesis, should incorporate such signal in the hydrogen isotopes of their tissues. However, a fundamental question still exits: do algal lipid biomarkers truly record lake water hydrogen isotopic ratios? We have measured hydrogen isotope fractionation by freshwater algae Botryococcus braunii (3 strains) grown under controlled conditions in the lab. In order to establish a good relationship between lipid ? D and water ? D, for each strain we set up cultures in five waters with different ? D. ? D of alkadienes and botryococcenes of Botryococcus brauni measured on GCIRMS showed strong positive linear relation with water ? D (R2=0.99). Hydrogen isotopic ratios in the algal hydrocarbons are about 165 ‰ more negative compared to the water at the start while they are 270 ‰ more negative compared to water ? D at harvest. Such linear relationships establish a foundation for reconstructing lake water level and thus precipitation anomaly by analyzing ? D of algal lipids preserved in lake sediments.

  18. Transcriptome analysis of an oil-rich race A strain of Botryococcus braunii (BOT-88-2) by de novo assembly of pyrosequencing cDNA reads.

    PubMed

    Baba, Masato; Ioki, Motohide; Nakajima, Nobuyoshi; Shiraiwa, Yoshihiro; Watanabe, Makoto M

    2012-04-01

    To gain genetic information of oil-producing algae Botryococcus braunii, a novel dataset of 185,936 complementary DNA (cDNA) reads was obtained via pyrosequencing for the representative race A strain (strain BOT-88-2) exhibiting high oil productivity. The cDNA reads were assembled to retrieve 29,038 non-redundant sequences and 964 of them were successfully annotated based on similarity to database sequences. The transcriptome data embraced candidate genes for majority of enzymes involved in the biosynthesis of unsaturated very long-chain fatty acids. The transcriptome dataset has been deposited in the GenBank/EMBL/DDBJ database. PMID:22137751

  19. Structure and chemistry of a new chemical race of Botryococcus braunii (chlorophyceae) that produces lycopadiene, a tetraterpenoid hydrocarbon

    SciTech Connect

    Metzger, P.; Allard, B.; Casadevall, E. (UA CNRS, Paris (France)); Berkaloff, C.; Coute, A. (LA CNRS, Paris (France))

    1990-06-01

    New strains of the hydrocarbon rich alga Botryococcus braunii Kuetzing were isolated from water samples collected in three tropical freshwater lakes. These strains synthesize lycopadiene, a tetraterpenoid metabolite, as their sole hydrocarbon. The morphological and ultrastructural characteristics of these algae are similar to those reported for previously described strains which produce either alkadienes or botryococcenes. The pyriform shaped cells are embedded in a colonial matrix formed by layers of closely appressed external walls; this dense matrix is impregnated by the hydrocarbon and some other lipids. We believe the new strains synthesizing lycopadiene form a third chemical race in B. braunii, besides the alkadiene and botryococcene races, rather than a different species. Like the other two types of hydrocarbons, lycopadiene was produced primarily during the exponential and linear growth phases. The major fatty acid in the three races was oleic acid. This fatty acid was predominant in the alkadiene race; palmitic and octacosenoic acid also were present in appreciable amounts in the three races. Cholest-5-en-3{beta}-ol, 24-methylcholest-5-en-3{beta}-ol and 24-ethylcholest-5-en-3{beta}-ol occurred in the three races; three unidentified sterols also were detected in the lycopadiene race. Moreover, the presence of very long chain alkenyl-phenols in the lipids of algae of the alkadiene race was not observed in the botryococcene and lycopadiene races. Of the polysaccharides released in the medium, galactose appeared as a primary component: it predominated in the botryococcene race. The other major constituents were fucose for the alkadiene race and glucose and fucose for the lycopadiene race.

  20. Catalytic gasification of oil-extracted residue biomass of Botryococcus braunii.

    PubMed

    Watanabe, Hideo; Li, Dalin; Nakagawa, Yoshinao; Tomishige, Keiichi; Watanabe, Makoto M

    2015-09-01

    Catalytic gasification of the oil-extracted residue biomass of Botryococcus braunii was demonstrated in a laboratory-scale continuous feeding dual bed reactor. Steam gasification at 1023K over Ni-Fe/Mg/Al catalyst can completely reform tar derived from pyrolysis of the residue biomass into C1 gases and hydrogen, and has achieved 91%-C conversion to gaseous product (CO+CO2+CH4). Composition of product gas has higher contents of CO and H2 with their ratio (H2/CO) of around 2.4 which is slightly H2-rich syngas. Maximum hydrogen yield of 74.7mmolg-biomass(-1) obtained in this work is much higher than that from gasification of other algal biomass reported in literature. The residue biomass of B. braunii can be a superior renewable source of syngas or hydrogen. PMID:25817421

  1. C31-C34 methylated squalenes from a Bolivian strain of Botryococcus braunii.

    PubMed

    Achitouv, Etienne; Metzger, Pierre; Rager, Marie-Noëlle; Largeau, Claude

    2004-12-01

    Three new triterpenes, synthesized by a Bolivian strain of the green microalga Botryococcus braunii, were isolated and their chemical structures determined by 1D and 2D NMR, and mass spectrometry. These compounds are tri-, di-, and mono-methylsqualenes, co-occurring with the previously identified tetramethylsqualene and some C(30)-C(32) botryococcenes. In this strain, methylated squalenes constitute up to 24% of the total hydrocarbons and 4.5% of the dry biomass. The results of a pulse-chase experiment with L-[Me-(13)C] methionine provide evidence for the origin of these compounds via methylation of squalene at positions 3, 7, 18 and 22. PMID:15541746

  2. Extracellular terpenoid hydrocarbon extraction and quantitation from the green microalgae Botryococcus braunii var. Showa.

    PubMed

    Eroglu, Ela; Melis, Anastasios

    2010-04-01

    Mechanical fractionation and aqueous or aqueous/organic two-phase partition approaches were applied for extraction and separation of extracellular terpenoid hydrocarbons from Botryococcus braunii var. Showa. A direct spectrophotometric method was devised for the quantitation of botryococcene and associated carotenoid hydrocarbons extracted by this method. Separation of extracellular botryococcene hydrocarbons from the Botryococcus was achieved upon vortexing of the micro-colonies with glass beads, either in water followed by buoyant density equilibrium to separate hydrocarbons from biomass, or in the presence of heptane as a solvent, followed by aqueous/organic two-phase separation of the heptane-solubilized hydrocarbons (upper phase) from the biomass (lower aqueous phase). Spectral analysis of the upper heptane phase revealed the presence of two distinct compounds, one absorbing in the UV-C, attributed to botryococcene(s), the other in the blue region of the spectrum, attributed to a carotenoid. Specific extinction coefficients were developed for the absorbance of triterpenes at 190nm (epsilon = 90 +/- 5 mM(-1) cm(-1)) and carotenoids at 450 nm (epsilon=165+/-5mM(-1) cm(-1)) in heptane. This enabled application of a direct spectrophotometric method for the quantitation of water- or heptane-extractable botryococcenes and carotenoids. B. braunii var. Showa constitutively accumulates approximately 30% of the dry biomass as extractable (extracellular) botryococcenes, and approximately 0.2% of the dry biomass in the form of a carotenoid. It was further demonstrated that heat-treatment of the Botryococcus biomass substantially accelerates the rate and yield of the extraction process. Advances in this work serve as foundation for a cyclic Botryococcus growth, non-toxic extraction of extracellular hydrocarbons, and return of the hydrocarbon-depleted biomass to growth conditions for further product generation. PMID:20005092

  3. Raman spectroscopy analysis of botryococcene hydrocarbons from the green microalga Botryococcus braunii.

    PubMed

    Weiss, Taylor L; Chun, Hye Jin; Okada, Shigeru; Vitha, Stanislav; Holzenburg, Andreas; Laane, Jaan; Devarenne, Timothy P

    2010-10-15

    Botryococcus braunii, B race is a unique green microalga that produces large amounts of liquid hydrocarbons known as botryococcenes that can be used as a fuel for internal combustion engines. The simplest botryococcene (C(30)) is metabolized by methylation to give intermediates of C(31), C(32), C(33), and C(34), with C(34) being the predominant botryococcene in some strains. In the present work we have used Raman spectroscopy to characterize the structure of botryococcenes in an attempt to identify and localize botryococcenes within B. braunii cells. The spectral region from 1600-1700 cm(-1) showed ?(C=C) stretching bands specific for botryococcenes. Distinct botryococcene Raman bands at 1640 and 1647 cm(-1) were assigned to the stretching of the C=C bond in the botryococcene branch and the exomethylene C=C bonds produced by the methylations, respectively. A Raman band at 1670 cm(-1) was assigned to the backbone C=C bond stretching. Density function theory calculations were used to determine the Raman spectra of all botryococcenes to compare computed theoretical values with those observed. The analysis showed that the ?(C=C) stretching bands at 1647 and 1670 cm(-1) are actually composed of several closely spaced bands arising from the six individual C=C bonds in the molecule. We also used confocal Raman microspectroscopy to map the presence and location of methylated botryococcenes within a colony of B. braunii cells based on the methylation-specific 1647 cm(-1) botryococcene Raman shift. PMID:20705610

  4. Hydrogen isotope fractionation in freshwater algae: I. Variations among lipids and species

    E-print Network

    Sachs, Julian P.

    Hydrogen isotope fractionation in freshwater algae: I. Variations among lipids and species Zhaohui Abstract Five species of freshwater green algae, including three strains of Botryococcus braunii (two in the algae, including alkadienes, botryococcenes, heptadecenes, fatty acids, and phytadiene, were measured

  5. Application of memberane dispersion for enhanced lipid milking from Botryococcus braunii FACHB 357.

    PubMed

    Zhang, Fang; Cheng, Li-Hua; Xu, Xin-Hua; Zhang, Lin; Chen, Huan-Lin

    2013-05-10

    To improve the mixing efficiency in an aqueous-tetradecane system and thus to increase the lipid milking efficiency, poly (ether sulfones) hollow fiber membrane was applied as dispersion medium to establish an in situ lipid extraction process from Botryococcus braunii FACHB 357. The lipid location of this microalga was characterized by fluorescence microscope and transmission electron microscopy, respectively. The results showed that B. braunii excreted lipids into the outer matrix, which allowed it possible to extract algal lipids in situ by organic solvent. Within an aqueous-organic biphasic system, the lipid extraction ratio of tetradecane increased from 38.05% to 50.15% by introducing a microporous membrane as the dispersion medium, mainly because smaller solvent droplets were produced. Under this experimental condition (the volume ratio of tetradecane: 10%, the flow rate: 10 ml min(-1)), solvent toxicity and shearing stress had not shown significant impact on algal cells viability in 96 h. Within the same time period, the lipid amount extracted by solvent was enhanced with the increase of the solvent flow rate and the initial biomass concentration. These results suggested membrane dispersion was a good choice to improve mixing effect in the algal lipid milking process or other similar cell products extracted processes. PMID:23466999

  6. Changes in the hydrocarbon-synthesizing activity during growth of Botryococcus braunii B70.

    PubMed

    Niitsu, Rika; Kanazashi, Mana; Matsuwaki, Izumi; Ikegami, Yukiko; Tanoi, Takako; Kawachi, Masanobu; Watanabe, Makoto M; Kato, Misako

    2012-04-01

    Botryococcus braunii is a green, colonial microalga that produces large amounts of hydrocarbons. B. braunii B70 was estimated to be B race by the incorporation of radioactivity from l-[methyl(14)C]-methionine into hydrocarbon. The hydrocarbon-synthesizing activity of B70 cells was determined by feeding experiments using (14)C-compounds. NaH(14)CO(3) incorporation rate into the hydrocarbon was high in the early logarithmic growth phase but it declined thereafter. Hydrocarbon-synthesizing activity from [2-(14)C] pyruvate in 15-day cells was 80% of that in 5-day cells. In contrast, hydrocarbon-synthesizing activity from NaH(14)CO(3) and l-[methyl(14)C]-methionine decreased remarkably by 15 days after inoculation. Hence, the allocation of carbon was a regulatory step in hydrocarbon biosynthesis during the early logarithmic growth phase. The high activity of pentose phosphate pathway in the early logarithmic growth was seemed to be the contribution of the supply of NADPH for botryococcene synthesis. PMID:21925877

  7. Improvement of hydrocarbon recovery by spouting solvent into culture of Botryococcus braunii.

    PubMed

    Choi, Seung Phill; Bahn, Sang-Hoon; Sim, Sang Jun

    2013-12-01

    Botryococcus braunii, a green microalga, is known to produce plentiful liquid hydrocarbons as promising biodiesel resources. However, the hydrocarbon extraction methods that have so far achieved have several problems such as low efficiency and high cost. In our study, a solvent-spouted extraction process integrated with photo-bioculture was designed for simultaneous realization of hydrocarbon extraction and cell culture in two phases. The n-octane was selected as the best solvent among several solvents because its biocompatibility was highest for B. braunii. As a result, high level of biomass and hydrocarbon, 4.17 and 893.79 mg/L, respectively, was attained at 100 mL/min of solvent recycling rate through three times of processes for 66 days. Moreover, formation of cell clump was suppressed in solvent extraction, cells were regenerated after it, and thus cell viability was maintained even after repeated cycles of it. Finally, this solvent-spouted culture process required the smaller cost due to reuse of the less solvent and regenerated cells, compared with the other conventional methods. Accordingly, this technique would be applicable to exploit the continuous extraction of hydrocarbon from the algal biomass, especially for application on a large scale. PMID:23703677

  8. THE INFLUENCE OF THE ISOPROTURON HERBICIDE ON GROWTH, GASEOUS EXCHANGES AND ASSIMILATORY PIGMENT CONTENTS IN BOTRYOCOCCUS BRAUNII Kuetz

    Microsoft Academic Search

    Daniela Anca Lazãr

    The reactions of Botryococcus braunii Kuetz. cells treated with an urea compound, isoproturon, were inves- tigated. The effects on cells number, growth, assimila- tory pigment content and gas exchanges were recorded. Isoproturon was added in Zehnder -Gorham nutritive medium of algal suspension in increasing concentra- tions from 0.04 µM to 3 µM. For the concentration of 0.04 µM isoproturon, in

  9. Biological activities of dermatological interest by the water extract of the microalga Botryococcus braunii.

    PubMed

    Buono, Silvia; Langellotti, Antonio Luca; Martello, Anna; Bimonte, Marida; Tito, Annalisa; Carola, Antonietta; Apone, Fabio; Colucci, Gabriella; Fogliano, Vincenzo

    2012-11-01

    The use of microalgae in the skin care market is already established although the scientific rationale for their benefit was not clearly defined. In this work, the biological activities of dermatologic interest of the water extract from the microalga Botryococcus braunii (BBWE) were evaluated by a battery of in vitro assays. At concentrations ranging from 0.1 to 0.001 % (w/v) BBWE promoted adipocytes differentiation by inhibiting hormone-sensitive lipase, thus promoting triglyceride accumulation in the cells. BBWE also induced gene expression of proteins involved in the maintenance of skin cells water balance such as aquaporin-3 (AQP3), filaggrin (FLG) and involucrin (INV). 0.1 % BBWE increased the gene expression of AQP3 of 2.6-folds, that of FLG and INV of 1.5- and 1.9-folds, respectively. Moreover, it induced the biosynthesis of collagen I and collagen III by 80 and 40 %, respectively, compared to the untreated control. BBWE antioxidant activity, evaluated by oxygen radical absorbance capacity (ORAC) assay, was of 43.5 ?mol Trolox per gram of extract: a quite high value among those found for other microalgae extracts. BBWE inhibited the inducible nitric oxide synthase (iNOS) gene expression and the consequent nitrite oxide (NO) production under oxidative stress. At a concentration of 0.02 % BBWE reduced by 50 % the expression of iNOS and by about 75 % the NO production. Taken together, the results demonstrated that B. braunii water extract exerted an array of biological activities concurring with the skin health maintenance; therefore, it is a potential bioactive ingredient to be included in cosmetic products. PMID:22684780

  10. Unusual distribution of monomethylalkanes in Botryococcus braunii-rich samples: origin and significance

    NASA Astrophysics Data System (ADS)

    Audino, Michiele; Grice, Kliti; Alexander, Robert; Boreham, Christopher J.; Kagi, Robert I.

    2001-06-01

    A unique distribution of four homologous series of monomethylalkanes (MMAs) ranging from C 23 to C 31+ in the extractable organic matter and the hydrous pyrolysate of Permian torbanites has been observed for the first time. These components have been identified by gas chromatography-mass spectrometry and cochromatography of authentic standards. Each of the series begins with the 2-methylalkane. Each member of a particular homologous series has a common alkyl group, each series differing to the next by two carbon atoms. The members within each homologous series differ by the number of carbon atoms in the second alkyl group. These pronounced homologous series of MMAs are superimposed over the series of lower abundance, partially resolved, more commonly occurring MMAs. This distinct contrast in the distributions of the novel MMAs series and the more commonly occurring MMAs suggests two distinct sources of MMAs in the torbanites. This visual observation is borne out by compound specific carbon isotopic data. A detailed molecular carbon isotopic study in combination with structural data suggests that the unusual MMA series are either derived directly from Botryococcus braunii race A or are novel biomarkers indicative of intense heterotrophic reworking of the algal biomass.

  11. Effect of cobalt enrichment on growth and hydrocarbon accumulation of Botryococcus braunii with immobilized biofilm attached cultivation.

    PubMed

    Cheng, Pengfei; Wang, Junfeng; Liu, Tianzhong

    2015-02-01

    The effects of cobalt enrichment on the growth and hydrocarbon accumulation were studied with biofilm attached cultivation. Under biofilm attached cultivation conditions, the microalga Botryococcus braunii survived high concentration of cobalt (50× normal level). The crude hydrocarbon content as well as the long C chain component (C31) increased under Co enrichment treatment indicating the activity of key enzyme that catalyze hydrocarbon synthesis might be enhanced by Co enrichment. The reduced carbohydrate and protein contents accompanied by increased hydrocarbon content for Co enrichment treatment indicating the Co was also an effective factor that controls the carbon flow of B. braunii. Under Co enrichment treatment, totally 1473.9 ?mol of Co element was consumed to produce one gram of algal biomass, indicating this attached cultivation method is high efficient in heavy metal elements removal. PMID:25496939

  12. Culture of the hydrocarbon producing microalga Botryococcus braunii strain Showa: optimal CO2, salinity, temperature, and irradiance conditions.

    PubMed

    Yoshimura, Takeshi; Okada, Shigeru; Honda, Masaki

    2013-04-01

    Specific growth rates and hydrocarbon contents of Botryococcus braunii strain Showa were measured under a wide range of CO2, salinity, temperature, and irradiance conditions. The bubbling CO2 concentration of 0.2-5% and no addition of salinity were favorable conditions for growth. The strain cannot grow at 5°C and above 35°C under any irradiance levels. Maximum specific growth rate of 0.5 day(-1) (doubling time of 1.4 days), the highest value reported for B. braunii in the past studies, was observed at 30°C and 850 ?mol photons m(-2) s(-1). Since hydrocarbon productivity, shown as the product of hydrocarbon content and specific growth rate, increased with the increasing specific growth rate, we conclude that more efficient hydrocarbon production by the mass culture of strain Showa can be achieved by maintaining higher specific growth rate based on the culture conditions presented in this study. PMID:23428820

  13. Effects of soybean curd wastewater on the growth and hydrocarbon production of Botryococcus braunii strain BOT-22.

    PubMed

    Yonezawa, Natsuki; Matsuura, Hiroshi; Shiho, Makoto; Kaya, Kunimitsu; Watanabe, Makoto M

    2012-04-01

    A laboratory study was conducted to evaluate the possibility of using wastewater from a soybean curd manufacturing plant as a growth promoter of Botryococcus braunii strain BOT-22. Soybean curd wastewater (SCW) were added to AF-6 medium to set the final concentration to 0% (control), 1%, 2%, 5%, and 10% (v/v). The growth and hydrocarbon production observed in the cultures with 1% and 2% SCW were significantly higher than that observed in the control. It was postulated that proteins and/or reducing sugars in SCW could enhance the growth. A major finding was a shift in the chemical composition of hydrocarbons from C(34)H(58) to C(32)H(54) in association with increased concentrations of SCW. Considering the inorganic ions in SCW, it was presumed that a mixture of nitrate, 1-2% SCW, and secondarily treated SCW can be applied for mass cultivation of Botryococcus. PMID:21940163

  14. Preservation of algaenan and proteinaceous material during the oxic decay of Botryococcus braunii as revealed by pyrolysis-gas chromatography\\/mass spectrometry and 13C NMR spectroscopy

    Microsoft Academic Search

    Reno T Nguyen; H. Rodger Harvey; Xu Zang; Jasper D. H van Heemst; Magdolna Hetényi; Patrick G Hatcher

    2003-01-01

    Botryococcus braunii cells were grown until the late-stationary phase of growth and subsequently decomposed under oxic conditions for 201 days using a microbial consortium obtained from a freshwater lake. Degradation exhibited multi-G model kinetics, with a ‘labile’ fraction lost at a rate two to three times slower than those observed for the degradation of other previously studied phytoplankton, and a

  15. Simple, rapid and cost-effective method for high quality nucleic acids extraction from different strains of Botryococcus braunii.

    PubMed

    Kim, Byung-Hyuk; Ramanan, Rishiram; Cho, Dae-Hyun; Choi, Gang-Guk; La, Hyun-Joon; Ahn, Chi-Yong; Oh, Hee-Mock; Kim, Hee-Sik

    2012-01-01

    This study deals with an effective nucleic acids extraction method from various strains of Botryococcus braunii which possesses an extensive extracellular matrix. A method combining freeze/thaw and bead-beating with heterogeneous diameter of silica/zirconia beads was optimized to isolate DNA and RNA from microalgae, especially from B. braunii. Eukaryotic Microalgal Nucleic Acids Extraction (EMNE) method developed in this study showed at least 300 times higher DNA yield in all strains of B. braunii with high integrity and 50 times reduced working volume compared to commercially available DNA extraction kits. High quality RNA was also extracted using this method and more than two times the yield compared to existing methods. Real-time experiments confirmed the quality and quantity of the input DNA and RNA extracted using EMNE method. The method was also applied to other eukaryotic microalgae, such as diatoms, Chlamydomonas sp., Chlorella sp., and Scenedesmus sp. resulting in higher efficiencies. Cost-effectiveness analysis of DNA extraction by various methods revealed that EMNE method was superior to commercial kits and other reported methods by >15%. This method would immensely contribute to area of microalgal genomics. PMID:22662217

  16. Modes of hydrocarbon oil biosynthesis revealed by comparative gene expression analysis for race A and race B strains of Botryococcus braunii.

    PubMed

    Ioki, Motohide; Baba, Masato; Bidadi, Haniyeh; Suzuki, Iwane; Shiraiwa, Yoshihiro; Watanabe, Makoto M; Nakajima, Nobuyoshi

    2012-04-01

    To clarify the oil biosynthetic routes of the oil-producing green alga Botryococcus braunii, here the race-specific gene expression patterns were examined using representative strains of race A and race B producing fatty acid- and triterpene-derived hydrocarbon oils, respectively. The strain-specific gene expression patterns in the BOT-88-2 strain (race A) and the BOT-22 strain (race B) were revealed by transcriptome comparison and real-time PCR quantification. For race A, it was inferred from the gene expression patterns that the fatty acid elongation in the acyl-carrier-protein (acp)-bound form followed by further elongation in the coenzyme A (CoA)-bound form is the major route of oil biosynthesis. The fatty acids may be desaturated in both acp- and CoA-bound forms and once metabolized into glycerolipids prior to further elongation. For race B, relatively direct entry of photosynthetic products from the reductive pentose phosphate cycle into the mevalonate-independent triterpene biosynthesis was implicated. PMID:22257857

  17. Optimization of light for growth, photosynthesis, and hydrocarbon production by the colonial microalga Botryococcus braunii BOT-22.

    PubMed

    Sakamoto, Kohei; Baba, Masato; Suzuki, Iwane; Watanabe, Makoto M; Shiraiwa, Yoshihiro

    2012-04-01

    Optimization of the light conditions for biofuel production by the microalga Botryococcus braunii BOT-22 (race B) was performed using monochromatic red light. The lipid and sugar contents were approximately 40% and 20-30% of the cell dry weight, respectively, and about half of the lipids were liquid hydrocarbons. The half-saturation intensities for the production rate of lipids, hydrocarbons, and sugars were 63, 49, and 44?molm(-2)s(-1), respectively. Fluorescence microscopic images of Nile Red-stained cells showed an increased number of intracellular neutral lipid granules due to increased light intensity. After 16days of incubation in the dark, lipid and sugar, but not hydrocarbon content decreased. Growth, metabolite production, and photosynthesis were saturated at 100, 200 and 1000?molm(-2)s(-1), respectively. These results indicate that photosynthetically captured energy is not used efficiently for metabolite production; thus, improvements in metabolic regulation may increase hydrocarbon production. PMID:22334002

  18. Development of a draft-tube airlift bioreactor for Botryococcus braunii with an optimized inner structure using computational fluid dynamics.

    PubMed

    Xu, Ling; Liu, Rui; Wang, Feng; Liu, Chun-Zhao

    2012-09-01

    The key parameters of the inner structure of a cylindrical airlift bioreactor, including the ratio of the cross-section area of the downcomer to the cross-section area of the riser, clearance from the upper edge of the draft tube to the water level, and clearance from the low edge of the draft tube to the bottom of the reactor, significantly affected the biomass production of Botryococcus braunii. In order to achieve high algal cultivation performance, the optimal structural parameters of the bioreactor were determined using computational fluid dynamics (CFD) simulation. The simulated results were validated by experimental data collected from the microalgal cultures in both 2 and 40-L airlift bioreactors. The CFD model developed in this study provides a powerful means for optimizing bioreactor design and scale-up without the need to perform numerous time-consuming bioreactor experiments. PMID:22750496

  19. Characterization of the biofuel potential of a newly isolated strain of the microalga Botryococcus braunii Kützing from Assam, India.

    PubMed

    Talukdar, Jayanta; Kalita, Mohan Chandra; Goswami, Bhabesh Chandra

    2013-12-01

    Botryococcus braunii GUBIOTJTBB1 was isolated from a freshwater reservoir in Assam, India and its taxonomic identity was confirmed by 18S rRNA sequence analysis. Biofuel potential of the microalga strain was assessed from batch culture under laboratory conditions, based on its lipid content and energy value of the dried biomass. Total lipid of 57.14% and hexane extractable crude hydrocarbon of 52.6% were recorded maximum at 56 and 28 days respectively, which vary upon culture durations. The energy value (54.69 kJ/g) of the strain's sundried biomass was found higher than that of petroleum diesel fuel and nearly twice than other microalgae strains compared. The strain GUBIOTJTBB1 was found superior in terms of total lipid and hydrocarbon contents comparing to the previously reported Indian strains of B. braunii. With further improvements in growth, the strain could become an ideal feedstock for potential biofuel production in the prevailing climatic conditions of the region. PMID:24121368

  20. The similarity of chemical structures of soluble aliphatic polyaldehyde and insoluble algaenan in the green microalga Botryococcus braunii race A as revealed by analytical pyrolysis

    Microsoft Academic Search

    J. S. Sinninghe Damsté; F. Gelin; J. W. de Leeuw; S. Derenne; C. Largeau; P. Metzger

    1994-01-01

    Curie point pyrolysis-gas chromatographic-mass spectrometric studies of a recently isolated CHCl3-soluble aliphatic polyaldehyde, and of an insoluble biopolymer termed Bb(A) algaenan, of the green microalga Botryococcus braunii (race A) were performed to determine the structural relationships between these two polymers. Comparisons of specific mass chromatograms, and of the composition of three clusters of pyrolysis products, with different chain lengths of

  1. Molecular and Biochemical Characterization of Hydrocarbon Production in the Green Microalga Botryococcus braunii

    E-print Network

    Weiss, Taylor Leigh

    2012-10-19

    prescribed to lower cholesterol synthesis in humans (Miziorko 2011). The remainder of the mevalonate pathway requires two kinases and two ATP to generate 5-pyrophosphatemevalonate (Miziorko 2011). 5-pyrophosphatemevalonate is then decarboxylated to form... desaturation Decarboxylation Elongation & ?7 (cis) desaturation IsomerizationA B Elongation by C2 unit, malonyl-CoA condensation Terminal decarboxylation FIGURE 12. B. braunii, A race n-long chain hydrocarbon synthesis. Hydrocarbons of the A race...

  2. Transcriptome analysis of an oil-rich race B strain of Botryococcus braunii (BOT-22) by de novo assembly of pyrosequencing cDNA reads.

    PubMed

    Ioki, Motohide; Baba, Masato; Nakajima, Nobuyoshi; Shiraiwa, Yoshihiro; Watanabe, Makoto M

    2012-04-01

    To gain genetic insights into the biosynthesis of botryococcene oils in Botryococcus braunii race B, a transcriptome dataset of the BOT-22 strain containing 27,427 non-redundant sequences assembled from 209,429 complementary DNA reads was obtained via high-throughput 454 sequencing. Relatively reliable prediction of the gene product was feasible for 725 non-redundant sequences based on homology to previously characterized database sequences. Regarding the botryococcene oil biosynthesis, genes putatively associated with the mevalonate-independent isoprenoid biosynthesis pathway were retrieved, while no genes were found for the mevalonate pathway, suggesting that botryococcenes are biosynthesized through the mevalonate-independent pathway in B. braunii. All transcriptome sequences have been deposited in the GenBank/EMBL/DDBJ database. PMID:21963247

  3. Effect of light, nutrient, cultivation time and salinity on lipid production of newly isolated strain of the green microalga, Botryococcus braunii KMITL 2.

    PubMed

    Ruangsomboon, Suneerat

    2012-04-01

    The green microalga strain, Botryococcus braunii KMITL 2, was isolated from a freshwater reservoir in central Thailand, and the effects of light, nitrogen, phosphorus, iron, cultivation time and salinity on lipid production were studied by varying parameters one at a time. When cultured in Chlorella medium containing 222 mg L(-1) phosphorus (PO(4)(3-)-P) under continuous illumination of 200 ?E m(-2)s(-1) with a salinity of 0 psu, a maximum lipid content of 54.69 ± 3.13% was obtained. Its high lipid content makes strain KMITL 2 a potential source for biodiesel production in tropical regions. PMID:21803571

  4. Removal of CO{sub 2} from flue gases by algae. [Quarterly] technical report, March 1, 1993--May 31, 1993

    SciTech Connect

    Akin, C.; Pradhan, S. [Inst. of Gas Technology, Chicago, IL (United States)

    1993-09-01

    The objective of this research program is to determine the feasibility of the alga Botryococcus braunii as a biocatalyst for the photosynthetic conversion of flue gas CO{sub 2} to hydrocarbons. The research program involves the determination of the biocatalytic characteristics of free and immobilized cultures of Botryococcus braunii in bench-scale studies, and the feasibility study and economic analysis of the Botryococcus braunii culture systems for the conversion of flue gas CO{sub 2} to hydrocarbons. The objective of the third quarter of this research program was to determine the growth and hydrogen formation characteristics of free and immobilized cells of Botryococcus braunii in bench-scale photobioreactors. Raceway and inclined surface type bioreactors were used for free cell and immobilized cell studies respectively. The free cell studies with air and CO{sub 2} enriched air [10% (v/v) CO{sub 2} in air] in media with and without NaHCO{sub 3} were conducted.

  5. Gradient HPLC of samples extracted from the green microalga Botryococcus braunii using highly efficient columns packed with 2.6 ?m Kinetex-C?? core-shell particles.

    PubMed

    Gritti, Fabrice; Perdu, Marie-Agnès; Guiochon, Georges

    2012-03-16

    The analysis of the nonpolar extract of the cells of colonies of the green colonial microalgae Botryococcus braunii was performed by gradient HPLC. The growth of B. braunii was stressed by reducing its nitrogen nutrients by 90%, in order to enhance the production of nonpolar compounds. Highly efficient 4.6mm × 100mm columns packed with 2.6 ?m Kinetex-C(18) core-shell particles (Phenomenex, Torrance, CA, USA) were used. The gradient mobile phase was a mixture of acetonitrile and water (70-97%, v/v). Its initial and final compositions during the gradient elution were chosen so that the retention factors of the last eluted compound at the inlet and outlet of the column were 15 and 1, respectively. The highest peak capacity was obtained by optimizing several experimental parameters, including the injected sample volume, the flow rate, and the column length. The highest resolution was obtained by connecting one 4.6 mm × 150 mm and three 4.6mm × 100mm columns (total length 45 cm). The optimum flow rate was 1.5 mL/min, which provided the minimum plate height for the most retained compounds, the optimum inlet pressure was 930 bar and the injected volume 2 ?L. The analysis time was then 14 min for a peak capacity of 121. The trends observed for the variation of the experimental peak capacity with the flow rate and the column length are in excellent agreement with theoretical predictions. PMID:22307155

  6. Effects of different media and nitrogen sources and levels on growth and lipid of green microalga Botryococcus braunii KMITL and its biodiesel properties based on fatty acid composition.

    PubMed

    Ruangsomboon, Suneerat

    2015-09-01

    This work aimed to find an optimum culture medium for green microalga Botryococcus braunii KMITL and investigate its biodiesel properties based on fatty acid composition. Four different media were tested. Chlorella medium was the best medium for lipid yield. Among four nitrogen sources tested, KNO3 produced the highest lipid yield. When varied the nitrogen concentrations, this strain gave the highest lipid yield at the highest nitrogen level. When cultivated in the best medium and nitrogen source and level for 30days, and then cultivated further for 14days in the medium with no nitrogen, the highest lipid content and yield were 49.94±0.82% and 2.71±0.02gL(-1), respectively. C16:0 fatty acid was the major fatty acid found. Fatty acid profiles of B. braunii KMITL cultivated in Chlorella medium with 1.25gL(-1) KNO3 gave the best biodiesel properties with the lowest iodine value, maximum cetane number, and lowest degree of unsaturation. PMID:25677535

  7. Monitoring lipid accumulation in the green microalga Botryococcus braunii with frequency-modulated stimulated Raman scattering

    NASA Astrophysics Data System (ADS)

    Wang, Chun-Chin; Chandrappa, Dayananda; Smirnoff, Nicholas; Moger, Julian

    2015-03-01

    The potential of microalgae as a source of renewable energy has received considerable interest because they can produce lipids (fatty acids and isoprenoids) that can be readily converted into biofuels. However, significant research in this area is required to increase yields to make this a viable renewable source of energy. An analytical tool that could provide quantitative in situ spectroscopic analysis of lipids synthesis in individual microalgae would significantly enhance our capability to understand the synthesis process at the cellular level and lead to the development of strategies for increasing yield. Stimulated Raman scattering (SRS) microscopy has great potential in this area however, the pump-probe signal from two-color two-photon absorption of pigments (chlorophyll and carotenoids) overwhelm the SRS signal and prevent its application. Clearly, the development of a background suppression technique is of significant value for this important research area. To overcome the limitation of SRS in pigmented specimens, we establish a frequency-modulated stimulated Raman scattering (FM-SRS) microscopy that eliminates the non-Raman background by rapidly toggling on-and-off the targeted Raman resonance. Moreover, we perform the background-free imaging and analysis of intracellular lipid droplets and extracellular hydrocarbons in a green microalga with FM-SRS microscopy. We believe that FM-SRS microscopy demonstrates the potential for many applications in pigmented cells and provides the opportunity for improved selective visualization of the chemical composition of algae and plants

  8. Reclaimed Water and Secondary Wastewater as Alternative Growing Media for Green Algae for Biofuel Production

    Microsoft Academic Search

    Sara S. Kuwahara; Joel L. Cuello

    The microalga Botryococcus braunii is one of many photosynthtic algae species being investigated as renewable feedstocks for production of biofuels. One key advantage of algae as biofuel feedstock, in view of the growing scarcity of fresh water worldwide, is the potential of algae to grow in low-quality water, including in the nutrient-containing effluents from wastewater-treatment plants. Indeed, algae could also

  9. New insights on the structure of algaenan from Botryoccocus braunii race A and its hexane insoluble botryals based on multidimensional NMR spectroscopy and electrospray–mass spectrometry techniques

    Microsoft Academic Search

    Andre J Simpson; Xu Zang; Robert Kramer; Patrick G Hatcher

    2003-01-01

    Through solution state NMR spectroscopy and quadrupole-time-of-flight mass spectrometry (Q-TOF MS) studies of the hexane insoluble botryal extract of the algae Botryococcus braunii race A, coupled with high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy of the algaenan from this alga, it has been possible to advance the structural understanding of this geochemically important biopolymer. It was found that the hexane insoluble botryals

  10. Transcriptome analysis of an oil-rich race B strain of Botryococcus braunii (BOT-70) by de novo assembly of 5'-end sequences of full-length cDNA clones.

    PubMed

    Ioki, Motohide; Baba, Masato; Nakajima, Nobuyoshi; Shiraiwa, Yoshihiro; Watanabe, Makoto M

    2012-04-01

    Here the transcriptome of an oil-rich race B strain of Botryococcus braunii (BOT-70) was analyzed to mine genetic information useful in biofuel development. A full-length-enriched cDNA library was constructed via the oligo-capping method and the 5' ends of 11,904 randomly chosen cDNA clones were sequenced. Homology search using BLASTX identified candidate BOT-70 genes for majority of the reactions required for biosynthesis of botryococcenes through the mevalonate-independent pathway. The sequence retrieval from the transcriptome dataset implicated that an alternative entry route into the mevalonate-independent pathway via xylulose-5-phosphate, rather than the conventional entry route via 1-deoxy-d-xylulose-5-phosphate, is predominantly active. Analysis of N-terminal sequences of the retrieved genes indicated that the final reactions of botryococcene biosynthesis are likely to take place outside of chloroplasts. The transcriptome dataset has been deposited in the GenBank/EMBL/DDBJ database. PMID:22217731

  11. Blue Light, a Positive Switch Signal for Nitrate and Nitrite Uptake by the Green Alga Monoraphidium braunii1

    PubMed Central

    Aparicio, Pedro J.; Quiñones, Miguel A.

    1991-01-01

    Blue light was shown to regulate the utilization of oxidized nitrogen sources by green algae, both by activating nitrate reductase and promoting nitrite reductase biosysnthesis (MA Quiñones, PJ Aparicio [1990] Inorganic Nitrogen in Plants and Microorganisms, Springer-Verlag, Berlin, pp 171-177; MA Quiñones, PJ Aparicio [1990] Photochem Photobiol 51: 681-692). The data reported herein show that, when cells of Monoraphidium braunii at pH 8, containing both active nitrate reductase and nitrite reductase, were sparged with CO2-free air and irradiated with strong background red light, they took up oxidized nitrogen sources only when PAR comprised blue light. The activation of the transport system(s) of either both nitrate and nitrite was very quick and elicited by low irradiance blue light. In fact, blue light appears to act as a switch signal from the environment, since the uptake of these anions immediately ceased when this radiation was turned off. The requirement of blue light for nitrate uptake was independent of the availability of CO2 to cells. However, cells under high CO2 tensions, although they showed an absolute blue light requirement to initially establish the uptake of nitrite, as they gained carbon skeletons to allocate ammonia, gradually increased their nitrite uptake rates in the subsequent red light intervals. Under CO2-free atmosphere, cells irradiated with strong background red light of 660 nanometers only evolved oxygen when they were additionally irradiated with low irradiance blue light and either nitrate or nitrite was present in the media to provide electron acceptors for the photosynthetic reaction. PMID:16667993

  12. Removal of CO{sub 2} from flue gases by algae. Final technical report, September 1, 1992--August 31, 1993

    SciTech Connect

    Akin, C.; Maka, A.; Patel, S.; Conrad, J. [Inst. of Gas Technology, Chicago, IL (United States); Benemann, J.

    1993-12-31

    The objective of this research program is to determine the feasibility of the alga Botryococcus braunii as a biocatalyst for the photosynthetic conversion of flue gas CO{sub 2} to hydrocarbons. Free and immobilized cells of Botryococcus braunii were grown in aqueous medium supplemented with nitrogen, phosphorus and mineral nutrients. Air and CO{sub 2} enriched air [10% to 15% (V/V) CO{sub 2}] in the gas phase and 0.2% to 2% NaHCO{sub 3} in the liquid medium served as the carbon source. Growth and hydrocarbon formation characteristics of free and immobilized cultures of Botryococcus braunii were determined in bench-scale photobioreactors. Technical and economic feasibility of the conversion of flue gas CO{sub 2} to hydrocarbons by Botryococcus braunii culture systems was evaluated. In free cell systems, the hexane extractable oil productivity was about 15 to 37 grams of oil per 100 grams of cell dry weight. In immobilized cell systems, the oil production ranged between 5% and 47% at different immobilization systems and immobilized surface locations, with an average of 19% of cell biomass dry weight. The feasibility and economic evaluation estimated the cost of oil produced from flue gas CO{sub 2} by algae to range between $45 and $75 per barrel assuming that a hydrocarbon yield of about 50% of the biomass weight is achievable and a credit of $60 per ton of carbon removed is available. A future research program leading to development of a multistage process, consisting of closed systems for heavy inoculum buildup followed by lower cost open systems for oil production is recommended.

  13. 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. PMID:22503193

  14. Characterization of the Heterotrimeric G-Protein Complex and Its Regulator from the Green Alga Chara braunii Expands the Evolutionary Breadth of Plant G-Protein Signaling1[C][W][OPEN

    PubMed Central

    Hackenberg, Dieter; Sakayama, Hidetoshi; Nishiyama, Tomoaki; Pandey, Sona

    2013-01-01

    The lack of heterotrimeric G-protein homologs in the sequenced genomes of green algae has led to the hypothesis that, in plants, this signaling mechanism coevolved with the embryophytic life cycle and the acquisition of terrestrial habitat. Given the large evolutionary gap that exists between the chlorophyte green algae and most basal land plants, the bryophytes, we evaluated the presence of this signaling complex in a charophyte green alga, Chara braunii, proposed to be the closest living relative of land plants. The C. braunii genome encodes for the entire G-protein complex, the G?, G?, and G? subunits, and the REGULATOR OF G-PROTEIN SIGNALING (RGS) protein. The biochemical properties of these proteins and their cross-species functionality show that they are functional homologs of canonical G-proteins. The subunit-specific interactions between CbG? and CbG?, CbG? and CbG?, and CbG? and CbRGS are also conserved, establishing the existence of functional G-protein complex-based signaling mechanisms in green algae. PMID:24179134

  15. Association of oil source algae in some Tertiary basins, northern Thailand

    NASA Astrophysics Data System (ADS)

    Ratanasthien, Benjavun

    1999-04-01

    A coal petrographic study of sediments, including coals, oil shale, and oil source rocks, in the fossil fuel deposits of northern Thailand revealed changes in alginite associations. In the Lower part of these Tertiary deposits, especially in the Fang oilfield, alginite A (a Botryococcus sp.) was the only type of alga found. Later, the association of Botryococcus braunii, Pila algae, thick-walled alginite B, and temperate palynomorphs were recognized in many coalfields, as well as in the middle part of the deposits in the Fang Basin. Their ages were Late Oligocene (?) to Early Miocene. In the upper part of the fossil fuel deposits, alginite B is dominant in many basins, together with Botryococcus-related taxa such as Pila algae, Reinschia and fresh-water-dwelling ferns. In the Mae Sod Basins Reinschia was found to be dominant in the northern part, whereas lamaginite dominated in the south, showing different environmental conditions in different parts of the basin during deposition. These different associations indicate changes in depositional environments in northern Thailand, resulting from climatic and/or sea level changes during Tertiary time.

  16. Hydrocarbon productivities in different Botryococcus strains: comparative methods in product quantification.

    PubMed

    Eroglu, Ela; Okada, Shigeru; Melis, Anastasios

    2011-08-01

    Six different strains of the green microalgae Botryococcus belonging to the A-race or B-race, accumulating alkadiene or botryococcene hydrocarbons, respectively, were compared for biomass and hydrocarbon productivities. Biomass productivity was assessed gravimetrically upon strain growth in the laboratory under defined conditions. Hydrocarbon productivities were measured by three different and independent experimental approaches, including density equilibrium of the intact cells and micro-colonies, spectrophotometric analysis of hydrocarbon extracts, and gravimetric quantitation of eluted hydrocarbons. All three hydrocarbon-quantitation methods yielded similar results for each of the strains examined. The B-race microalgae Botryococcus braunii var. Showa and Kawaguchi-1 constitutively accumulated botryococcene hydrocarbons equivalent to 30% and 20%, respectively, of their overall biomass. The A-race microalgae Botryococcus braunii, varieties Yamanaka, UTEX 2441 and UTEX LB572 constitutively accumulated alkadiene hydrocarbons ranging from 14% to 13% and 10% of their overall biomass, respectively. Botryococcus sudeticus (UTEX 2629), a morphologically different green microalga, had the lowest hydrocarbon accumulation, equal to about 3% of its overall biomass. Results validate the density equilibrium and spectrophotometric analysis methods in the quantitation of botryococcene-type hydrocarbons. These analytical advances will serve in the screening and selection of B. braunii and of other microalgae in efforts to identify those having a high hydrocarbon content for use in commercial applications. PMID:21909190

  17. Effects of nitrogen source and nitrogen supply model on the growth and hydrocarbon accumulation of immobilized biofilm cultivation of B. braunii.

    PubMed

    Cheng, Pengfei; Wang, Junfeng; Liu, Tianzhong

    2014-08-01

    The immobilized biofilm cultivation was a promising method to greatly improve the biomass productivity of microalga Botryococcus braunii, which was considered as an feedstock of renewable biofuel. In this research, the effects of different nitrogen sources and supply methods on growth and hydrocarbon production of B. braunii under immobilized biofilm cultivation (attached cultivation) were studied. Of the total 5 different nitrogen sources, NaNO? was selected as the best one with which the high biomass productivity and hydrocarbon productivity of 6.45 gm(-2)d(-1) and 2.79 gm(-2)d(-1) were obtained respectively. The optimized nitrogen concentration was 0.99 mM for non-circulating medium supply model, while for the circulating model, the optimized nitrogen concentration as well as medium volume was 1.49 mM and 1.2L, respectively. Furthermore, nitrogen inputs based on growth of 1 kg dry algae biomass was only 28.92 g with circulating model. Attached cultivation was high efficient in light, nutrient and water utilization. PMID:24951939

  18. New insights on the structure of algaenan from Botryoccocus braunii race A and its hexane insoluble botryals based on multidimensional NMR spectroscopy and electrospray-mass spectrometry techniques.

    PubMed

    Simpson, Andre J; Zang, Xu; Kramer, Robert; Hatcher, Patrick G

    2003-03-01

    Through solution state NMR spectroscopy and quadrupole-time-of-flight mass spectrometry (Q-TOF MS) studies of the hexane insoluble botryal extract of the algae Botryococcus braunii race A, coupled with high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy of the algaenan from this alga, it has been possible to advance the structural understanding of this geochemically important biopolymer. It was found that the hexane insoluble botryals in this study constitute a mixture of low molecular weight unsaturated aliphatic aldehydes and unsaturated hydrocarbons with an average chain length of about 40 carbons. Exact assignments were provided for many of the structural units present and describe the average constitution of the mixture as a whole. Reticulation of the low molecular weight chains via acetal and ester links explains the primary make up of algaenan. In this study, it is concluded that the algaenan results from the reticulation of low molecular weight hexane insoluble botryal species rather than the polyaldehyde as previously observed in studies of algae at alternate stages of their growth cycle. PMID:12620332

  19. Low polarity pyrolysis products of Permian to Recent Botryococcus -rich sediments: First evidence for the contribution of an isoprenoid algaenan to kerogen formation

    Microsoft Academic Search

    S. Derenne; C. Largeau; F. Behar

    1994-01-01

    Hydrocarbon identification led to the recognition of three distinct chemical races in the green microalga Botryococcus braunii . These three races ( A , B , and L ) also show pronounced differences in the chemical structure of the algaenans, i.e., the insoluble, highly aliphatic, nonhydrolysable macromolecular constituents (termed PRB) of their outer walls. PRB A and PRB B are

  20. [Diurnal progress of NADP-linked glyceraldehyde-3-phosphate-dehydrogenase in synchronous culture of unicellular green alga Ankistrodesmus braunii and its susceptibility to X-irradiation and inhibitiors of protein synthesis].

    PubMed

    Theiss-Seuberling, H B

    1975-06-22

    1. The daily progress of NADP-linked GPD-activity rise in synchronous culture of Ankistrodesmus braunii was investigated in respect to short time increase of activity by light. After various exposure times cells were temporarily deprived of light and subsequently the so-called dark value as well as the light value (dark value plus light-induced part) of the enzyme activity was determined. 2. The increase of dark and light values per cell number is greater in the first half of the day than in the second. The minor activity rise in the second half seems to be caused by culture conditions since the activity of the light and dark values-after reduction of cell density to half in the early afternoon-shows a greater increase again. With regard to chlorophyll, around noon the enzymes activity reaches a maximum which corresponds to numerous other physiological maxima in synchronous algae cultures. 3. The absolute value of the light-induced part of NADP-linked GPD-activity per cell number also increases with increasing exposure time in the first half of the day more than in the second. 4. X-irradiation retards the rise of the dark value of the NADP-GPD. This is particularly evident if the cells are exposed to light for 4 hrs after X-irradiation: 10-25 krad is enough to completely arrest the rise of the dark value. 5. The light-induced part of GDP-activity is hardly affected by high X-ray doses (424 krad), either immediately following the X-irradiation altered the effect of the irradiation: the rise of the dark value was not as great as the control; the light-induced part of enzyme activity was obviously retarded more than it had been after only 4 hrs exposure time. Thus it can be assumed that with regard to the dark value of GPD-activity there is a recovery from the irradiation damage, whereas the radiation effect on the light-induced part of GDP-activity is possibly increased. 8. The D37 of chlorophyll synthesis of synchronous Ankistrodesmus cultures is approximately 85 krad and is thus, like the rise of the light-induced increase of NADP-linked GPD-activity, substantially more radiation resistent than the rise of the dark value which for a plant organism is extremely sensitive. 9. The high radiation sensitivity of the dark value rise of the GPD-activity in Ankistrodesmus braunii is compared with the relatively radiation resistent rise of this enzyme activity in resting greening Euglena gracilis, which contrary to Ankistrodesmus is not retarded by actinomycine, but only by chloramphenicol. One of the hypotheses under discussion regarding the X-ray effect is that the transcription processes which probably occur additionally for the rise in activity of the dark value of NADP-linked GPD may be the particularly radiation sensitive processes in Ankistrodesmus braunii. PMID:808190

  1. Removal of CO{sub 2} from flue gases by algae. Technical report, December 1, 1992--February 28, 1993

    SciTech Connect

    Akin, C.; Maka, A.; Pradhan, S. [Institute of Gas Technology, Chicago, IL (United States); Banerjee, D. [Illinois Clean Coal Inst., Carterville, IL (United States)

    1993-05-01

    The studies reported here confirmed our preliminary observations that Botryococcus braunii can tolerate and grow well in flue gas CO{sub 2} concentrations of 10 to 15%, and produce oil. The highest extracted oil was observed in 10% CO{sub 2} enriched air. Initial pH of the medium at or near 10 pH is favorable to cell growth probably by stimulating the CO{sub 2} solubilization in the medium. This is also indicated in Botryococcus braunii growth and oil formation in NaHCO{sub 3} added medium. The lack of growth in Na{sub 2}CO{sub 3} containing media was probably due to high pH. The CaCO{sub 3} precipitation from the CA{sup ++} gelled alginate beads indicate the need for alternative immobilization systems. But the attachment of the Botryococcus braunii cells to the bottom inner surfaces of the photobioreactors may eliminate the need for gel entrapment systems as the immobilization matrices. Attachment of the Botryococcus braunii cells to the bottom inner surfaces of the photobioreactors, rather than remaining in the suspension, reduces the significance of self shadowing and related liquid height (thickness) effect. The capability of Botryococcus braunii to grow in NaHCO{sub 3} solutions is very encouraging toward development of an alkaline scrubbing system for the flue gas followed by removal of the CO{sub 2} from the alkaline solution. In such a system the pH 10 is the currently observed upper limit.

  2. Freshwater chlorophycean algae in recent marine sediments of the Beaufort, Laptev and Kara Seas (Arctic Ocean) as indicators of river runoff

    NASA Astrophysics Data System (ADS)

    Matthiessen, Jens; Kunz-Pirrung, Martina; Mudie, Peta J.

    2000-11-01

    Freshwater chlorophycean algae are characteristic organic-walled microfossils in recent coastal and shelf sediments from the Beaufort, Laptev and Kara seas (Arctic Ocean). The persistent occurrence of the chlorophycean algae Pediastrum spp. and Botryococcus cf. braunii in marine palynomorph assemblages is related to the discharge of freshwater and suspended matter from the large Siberian and North American rivers into the Arctic shelf seas. The distribution patterns of these algae in the marine environments reflect the predominant deposition of riverine sediments and organic matter along the salinity gradient from the outer estuaries and prodeltas to the shelf break. Sedimentary processes overprint the primary distribution of these algae. Resuspension of sediments by waves and bottom currents may transport sediments in the bottom nepheloid layer along the submarine channels to the shelf break. Bottom sediments and microfossils may be incorporated into sea ice during freeze-up in autumn and winter leading to an export from the shelves into the deep sea. The presence of these freshwater algae in sea-ice and bottom sediments in the central Arctic Ocean confirm that transport in sea ice is an important process which leads to a redistribution of shallow water microfossils.

  3. Effects of cadmium and copper on the ultrastructure of Ankistrodesmus braunii and Anabaena 7120

    Microsoft Academic Search

    A. Massalski; V. M. Laube; D. J. Kushner

    1981-01-01

    The effects of brief exposure to, or growth in the presence of, lethal and sublethal concentrations of Cu(NO)2 and Cd(NO3) on the ultrastructure of the blue-green algaAnabaena 7120 and the green algaAnkistrodesmus braunii were studied. Exposure to increasing amount of both metal ions led to the appearance of larger proportions of electron-dense cells whose organelles were less well defined than

  4. Morphology and cultural behavior of Botryococcus protuberans with notes on the genus.

    PubMed

    Rai, U N; Dwivedi, S; Baghel, V S; Tripathi, R D; Shukla, O P; Shukla, M K

    2007-04-01

    The green alga Botryococcus protuberans was isolated from its natural environment and its morphology under different cultural conditions was examined. The alga was characterized by a high starch content and reddish oil drops as the assimilatory products. Photosynthetic pigments, Chl a, Chl b, carotenoids and xanthophylls are present. Modification of environmental conditions in modified Chu-10 medium resulted in optimum growth of the alga. Fatty acid composition revealed palmitic acid being the major component, while lauric acid, myristic acid and stearic acid were found in less quantity. PMID:17915747

  5. Low polarity pyrolysis products of Permian to Recent Botryococcus-rich sediments: First evidence for the contribution of an isoprenoid algaenan to kerogen formation

    NASA Astrophysics Data System (ADS)

    Derenne, S.; Largeau, C.; Behar, F.

    1994-09-01

    Hydrocarbon identification led to the recognition of three distinct chemical races in the green microalga Botryococcus braunii. These three races (A, B, and L) also show pronounced differences in the chemical structure of the algaenans, i.e., the insoluble, highly aliphatic, nonhydrolysable macromolecular constituents (termed PRB) of their outer walls. PRB A and PRBB are based upon polymethylenic chains, while PRB L is based on C40 isoprenoid moieties. Previous studies demonstrated that the selective preservation of PRB A and/or PRB B played a major role in the genesis of various Botryococcus-derived kerogens; in sharp contrast, the above kerogens did not show any indices of a PRB L contribution. The main purpose of this study was therefore to examine, via the screening of a number of Botryococcus-derived kerogens, if some contribution of PRB L, i.e., of an "isoprenoid algaenan", could be observed. To this end, the pyrolysis products of the three PRB and of seven Botryococcus-rich kerogens were examined. Parallel study of the algaenans of the three races of B. braunii indicated that a clear-cut distinction can be made, by analysis of low polarity pyrolysis products, between PRB A and PRB B, on the one hand, and PRB L, on the other hand. Thereafter, identification of the low polarity pyrolysis products of Botryococcus-rich kerogens revealed some contribution of the L race, along with the A or B race, in three samples out of seven: a Pliocene Torbanite and two Recent sediments. These observations thus provided the first example of the formation of kerogen fractions by the selective preservation of an algaenan based on isoprenoid chains. But they also revealed that important transformations of such chains can take place during kerogen early diagenesis. In sharp contrast, examination of the four Palaeozoic Torbanites revealed a complete lack of isoprenoid moieties, and hence no evidence of PRB L contribution. Comparison of n-alkane/n-alk-1-ene doublet distribution in the pyrolysate of these four kerogens, derived from the A and/or B races, showed some differences in their degree of maturation and in the contribution of higher plant materials to their formation.

  6. Thermal decomposition processes in algaenan of Botryococcus braunii race L. Part 1: Experimental data and structural evolution

    Microsoft Academic Search

    Elodie Salmon; Françoise Behar; François Lorant; Patrick G. Hatcher; Pierre Metzger; Paul-Marie Marquaire

    2009-01-01

    The thermal reactivity of organic matter in source rocks is usually kinetically represented by a set of parallel and independent first order reactions. The approach assumes that only defunctionalisation reactions take place upon thermal decomposition, regardless of the chemical nature of kerogen. We have developed a new method for evaluating maturation pathways for an important kerogen-forming geopolymer, algaenan from the

  7. Zygnematacean zygospores and other freshwater algae from the Upper Cretaceous of the Yellow Sea Basin, southwest coast of Korea

    Microsoft Academic Search

    Sangheon Yi

    1997-01-01

    Palynological assemblages recovered from intervals of late Maastrichtian age in the Kachi-1 and Inga-1 wells, Yellow Sea Basin, contain a high population of freshwater algae. These algal assemblages are characterised by common to abundant zygospores (Brazilea,Kachiisporis,Lecaniella,OvoiditesandTetranguladinium) and planktonic green algae (includingPediastrumandBotryococcus), and occur together with water-fern megaspores (e.g.,AzollaandGoshispora). Of twenty seven species belonging to fifteen genera, one genus and eight

  8. Botryococcene - A tetramethylated acyclic triterpenoid of algal origin

    NASA Technical Reports Server (NTRS)

    Cox, R. E.; Burlingame, A. L.; Wilson, D. M.; Eglinton, G.; Maxwell, J. R.

    1973-01-01

    The green alga Botryococcus braunii, implicated in the formation of certain geological deposits, produces unusual isomeric C34H58 alkenes, botryococcene and isobotryococcene, during a particular physiological state. A structure for botryococcene is suggested, taking into account NMR techniques, oxidative degradation, and established biosynthetic principles. Botryococcene appears terpenoid in origin.

  9. Heterotrimeric G-proteins in green algae

    PubMed Central

    Hackenberg, Dieter; Pandey, Sona

    2014-01-01

    Heterotrimeric G-proteins (G-proteins, hereafter) are important signaling components in all eukaryotes. The absence of these proteins in the sequenced genomes of Chlorophycean green algae has raised questions about their evolutionary origin and prevalence in the plant lineage. The existence of G-proteins has often been correlated with the acquisition of embryophytic life-cycle and/or terrestrial habitats of plants which occurred around 450 million years ago. Our discovery of functional G-proteins in Chara braunii, a representative of the Charophycean green algae, establishes the existence of this conserved signaling pathway in the most basal plants and dates it even further back to 1–1.5 billion years ago. We have now identified the sequence homologs of G-proteins in additional algal families and propose that green algae represent a model system for one of the most basal forms of G-protein signaling known to exist to date. Given the possible differences that exist between plant and metazoan G-protein signaling mechanisms, such basal organisms will serve as important resources to trace the evolutionary origin of proposed mechanistic differences between the systems as well as their plant-specific functions. PMID:24614119

  10. Green Algae

    NSDL National Science Digital Library

    Wim van Egmond

    2010-01-01

    Color photomicrographs of several species of green algae with brief descriptions of their chief characteristics and habitat. Scroll to the bottom of the page to links to bacteria, and more protists including diatoms, desmids and rotifers.

  11. Algae Biodiesel: Commercialization

    E-print Network

    Tullos, Desiree

    Algae Biodiesel: A Path to Commercialization Algae Biodiesel: A Path to Commercialization Center conservation and biomonitoring · Algae biodiesel is largest CEHMM project #12;Project Overview: The Missing replace petroleum #12;Project Overview: Local Resources for Algae Biodiesel Project Overview: Local

  12. Blue-green algae

    MedlinePLUS

    ... Lac Klamath, Anabaena, Aphanizomenon flos-aquae, Arthrospira maxima, Arthrospira platensis, BGA, Blue Green Algae, Blue-Green Micro-Algae, Cyanobacteria, Cyanobactérie, Cyanophycée, Dihe, Espirulina, Hawaiian Spirulina, Klamath, Klamath Lake Algae, Lyngbya wollei, Microcystis aeruginosa, ...

  13. Composition and structure of assimilatory nitrate reductase from Ankistrodesmus braunii.

    PubMed

    De la Rosa, M A; Vega, J M; Zumft, W G

    1981-06-10

    Assimilatory NAD(P)H-nitrate reductase (EC 1.6.6.2) from Ankistrodesmus braunii has been purified to homogeneity by affinity chromatography on blue Sepharose. The specific activity of the purified enzyme is in the range of 72 to 80 units/mg of protein. The electronic spectrum of the native enzyme shows absorption maxima at 278, 414 (Soret), 532 (beta), 562 (alpha), and 669 nm and shoulders at 455 and 484 nm, with an A278/A414 ratio of 2.56. The reduced enzyme shows absorption maxima at 424 (Soret), 528 (beta), 557 (alpha),and 669 n. The enzyme complex (Mr = 467,400) is composed of eight similar subunits (Mr = 58,750) and contains 4 molecules of FAD, 4 heme groups, and 2 atoms of molybdenum. Labile sulfide and nonheme iron were not detected. Electron micrographs show the eight subunits arranged alternately in two planes, and an 8-fold rotational symmetry was deduced from highly magnified images processed by optical superposition. PMID:7195400

  14. A comparative study of fossil and extant algaenans using ruthenium tetroxide degradation

    Microsoft Academic Search

    Peter Blokker; Stefan Schouten; Jan W. de Leeuw; Jaap S. Sinninghe Damsté; Herman van den Ende

    2000-01-01

    In this study the chemical structure of algaenans isolated from the freshwater algae Tetraedron minimum, Pediastrum boryanum and Botryococcus braunii are compared with their fossil counterparts by means of RuO4 oxidation. The results show that the algaenans investigated are preserved in sediments with only minor structural alterations. However, product mixtures from RuO4 degradation of the fossil algaenans exhibit a broader

  15. Hydrocarbon phenotyping of algal species using pyrolysis-gas chromatography mass spectrometry

    PubMed Central

    2010-01-01

    Background Biofuels derived from algae biomass and algae lipids might reduce dependence on fossil fuels. Existing analytical techniques need to facilitate rapid characterization of algal species by phenotyping hydrocarbon-related constituents. Results In this study, we compared the hydrocarbon rich algae Botryococcus braunii against the photoautotrophic model algae Chlamydomonas reinhardtii using pyrolysis-gas chromatography quadrupole mass spectrometry (pyGC-MS). Sequences of up to 48 dried samples can be analyzed using pyGC-MS in an automated manner without any sample preparation. Chromatograms of 30-min run times are sufficient to profile pyrolysis products from C8 to C40 carbon chain length. The freely available software tools AMDIS and SpectConnect enables straightforward data processing. In Botryococcus samples, we identified fatty acids, vitamins, sterols and fatty acid esters and several long chain hydrocarbons. The algae species C. reinhardtii, B. braunii race A and B. braunii race B were readily discriminated using their hydrocarbon phenotypes. Substructure annotation and spectral clustering yielded network graphs of similar components for visual overviews of abundant and minor constituents. Conclusion Pyrolysis-GC-MS facilitates large scale screening of hydrocarbon phenotypes for comparisons of strain differences in algae or impact of altered growth and nutrient conditions. PMID:20492649

  16. The oleaginous Botryococcus from the Triassic Yanchang Formation in Ordos Basin, Northwestern China: Morphology and its paleoenvironmental significance

    NASA Astrophysics Data System (ADS)

    Ji, Li-ming; Yan, Kui; Meng, Fan-wei; Zhao, Min

    2010-05-01

    High abundance but rather low diversity algal fossils were found in the hydrocarbon source rocks of the Ch 7-2-Ch 7-3 section, Triassic Yanchang Formation in the Xifeng area of southwest Ordos Basin, which are mainly composed of prolific Leiosphaeridia and Botryococcus. Botryococcus colonies are of various forms; the majority is nubbly, with some of cluster and cotton shape. The nubbly colonies appear globular, cordiform, ternate petal, obtuse triangle, chrysanthemum shape and so on. Most Botryococcus are saffron or brown and are frequently covered with clay under transmission microscope, and shows strong yellow and light brown under fluorescence microscope. Botryococcus could live in freshwater and brackish water. The Botryococcus colonies that lived in fresh water are small with small single cells arranged radially, with undulant or indented edges. The Botryococcus colonies that lived in brackish water are bigger, with larger single cells arranged irregularly, with slippery contours. The most of Botryococcus are discovered from the organic-rich argillaceous sediment with abundant pyrites in the semi- and deep-lake facies, and shows they were preserved in low-energy reducing environments. Taphonomic characteristics of various microfossils and the present of Pediastrum in the phytoplankton flora indicate that they are in situ or near burial. The lake area of the Ordos Basin was gradually expanding and reaching its most extensive flood surface in the Ch 7 of Yanchang Formation interval during the Middle and Late Triassic, with warm climate, plentiful rainfall, and luxuriant vegetation, as determined by the environmental analysis with Botryococcus in Xifeng area. The presence of two ecological types of Botryococcus indicates that the salinity of lake water was fluctuating in the Ch 7 interval. The occurrence of symbiotic acritarchs and geochemical salinity indices show that the Ordos Lake was a typical fresh-water lake, which was gradually desalted, and its salinity fluctuation was narrow during the Mid-Later Triassic. The ecological type of the palynological flora discovered from the Ch 7 to Ch 8 in Xifeng area is similar to that from the Fuxian Lake, with abundant Botryococcus in the Yungui Plateau of China. These findings imply that the Ordos Basin was in a lower-latitude area of temperate to subtropical climate during the Middle and Late Triassic.

  17. Biogeography of Marine Algae

    E-print Network

    Biogeography of Marine Algae David J Garbary, St Francis Xavier University, Antigonish, Nova Scotia and vicariance in establishing distributions and as factors associated with speciation. Since eukaryotic algae. There are many species that are virtually cosmopolitan (e.g. the green alga Enteromorpha intestinalis, the red

  18. Alkaloids in marine algae.

    PubMed

    Güven, Kasim 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

  19. Alkaloids in Marine Algae

    PubMed Central

    Güven, Kas?m 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

  20. Brown blob (algae?) (Native) 

    E-print Network

    James R. Manhart

    2011-08-10

    the KASELCO commercial electrocoagulation system. The KASELCO electrocoagulation system successfully coagulated microalgae in laboratory testing. Aluminum and stainless steel electrodes successfully recovered algae in laboratory testing. Electricity consumed...

  1. BROWN ALGAE Colpomenia sinuosa

    E-print Network

    Sullivan, Matthew B.

    added. BLUE-GREEN, BROWN, RED, AND GREEN The common names for marine algae sort them into color groups Valonia ventricosa Valonia utricularis BLUE-GREEN, BROWN, RED, AND GREEN The common names for marine algae: blue-green (Cyanobacteria), brown (Phaeophyta), red (Rhodophyta), and green (Chlorophyta). These names

  2. Phytochemical screening and anticonvulsant studies of ethyl acetate fraction of Globimetula braunii on laboratory animals

    PubMed Central

    Aliyu, Musa Mumammad; Musa, Abdullahi Isma'il; Kamal, Muhammad Ja'afar; Mohammed, Magaji Garba

    2014-01-01

    Objective To investigate the phytochemical properties and the anticonvulsant potential of the ethyl acetate soluble fraction of ethanol leaf extract of Globimetula braunii, a plant used in ethnomedicine for the treatment of epilepsy. Methods The phytochemical screening was carried out using standard protocol while the anticonvulsant activity was studied using maximal electroshock test in chicks, pentylenetetrazole and 4-aminopyridine-induced seizures in mice. Results The preliminary phytochemical screening carried out on the crude ethanol extract revealed the presence of saponins, carbohydrates, flavonoids, tannins, anthraquinones and steroids. Similarly, tannins, flavonoids and steroids/terpenes were found to be present in the ethyl acetate fraction. In the pharmacological screening, 150 mg/kg of the fraction protected 83.33% of animals against pentylenetetrazole-induced seizure in mice whereas sodium valproate a standard anti-epileptic drug offered 100% protection. In the 4-aminopyridine-induced seizure model, the fraction produced a significant (P<0.05) increase in the mean onset of seizure in unprotected animals. The fraction did not exhibit a significant activity against maximal electroshock convulsion. The median lethal dose of the fraction was found to be 1?261.91 mg/kg. Conclusions These results suggest that the ethyl acetate fraction of Globimetula braunii leaves extract possesses psychoactive compound that may be useful in the management of petit mal epilepsy and lend credence to the ethnomedical use of the plant in the management of epilepsy. PMID:25182552

  3. Elemental composition and molecular structure of Botryococcus alginite in Westphalian cannel coals from Kentucky

    USGS Publications Warehouse

    Mastalerz, Maria; Hower, J.C.

    1996-01-01

    Botryococcus-derived alginites from the Westphalian Skyline, No. 5 Block, Leatherwood (eastern Kentucky) and Breckinridge (western Kentucky) coal beds have been analyzed for elemental composition and functional group distribution using an electron microprobe and micro-FTIR, respectively. The alginites from Kentucky show a carbon range of 81.6 to 92% and oxygen content of 3.5 to 9.5%. Sulphur content ranges from 0.66 to 0.84% and Fe, Si, Al and Ca occur in minor quantities. FTIR analysis demonstrates dominant CH2, CH3 bands and subordinate aromatic carbon in all alginites. The major differences between alginites are in the ratios of CH2 and CH3 groups and ratios between aromatic bands in the out-of-plane region. These differences suggest that, although the ancient Botryococcus derives from a selective preservation of a resistant polymer, it undergoes molecular and some elemental changes through the rank equivalent to vitrinite reflectance of 0.5-0.85%. Other differences, such as intensities of ether bridges and those of carboxyl/carbonyl groups, are attributed to differences in depositional environments.

  4. Algae Removal by Flotation

    Microsoft Academic Search

    Donald B. Aulenbach; Nazih K. Shammas; Lawrence K. Wang; Rodney C. Marvin

    \\u000a The importance of algae is discussed. Algae are a significant source of oxygen on Earth due to its capability of photosynthesis.\\u000a Further they are an efficient biological system for converting solar energy into plant life, a source of energy for higher\\u000a life. However, at high concentrations, called blooms, they can contribute tastes and odors, and even toxins to the surrounding

  5. Algae Harvest Energy Conversion

    Microsoft Academic Search

    Yung-Tse Hung; O. Sarafadeen Amuda; A. Olanrewaju Alade; I. Adekunle Amoo; Stephen Tiong-Lee Tay; Kathleen Hung Li

    \\u000a Algae harvest energy conversion to biofuel technology is a promising alternative to fossil fuel that has inherent pollution\\u000a attachment. With present resources available for the microalgae mass production and hence, high oil yield, microalgal can\\u000a sufficiently be a new source of renewable energy to replace the fossil fuels. In this chapter, algae description, composition,\\u000a cultivation, its conversion to biofuel, and

  6. The Harmful Algae Page

    NSDL National Science Digital Library

    Donald Anderson

    2004-06-17

    Relevant sections in this resource include What are Harmful Algal Blooms (HABs), an Introduction to Algal Blooms and "Red Tide", Algae Species (which algae are responsible for the harmful effects?), Adverse Impacts, Human Illness (food poisoning associated with harmful algal blooms & information on diagnosis and treatment), HAB Distribution Maps, HAB events in the United States and around the world, HAB related articles as printed in the news media, and a photo gallery of visible algal blooms, photomicrographs, and satellite imagery.

  7. Genomics of Marine Algae

    Microsoft Academic Search

    Susana M. Coelho; Svenja Heesch; Nigel Grimsley; Hervé Moreau; J. Mark Cock

    \\u000a The algae are an extremely diverse group of organisms from several different perspectives; including their phylogeny, their\\u000a basic biology and biochemistry, the range of complexity they exhibit and their adaptation to a large number of different habitats.\\u000a As a result, algal research touches on a broad spectrum of questions ranging from the importance of algae as key species in\\u000a marine

  8. Purification and properties of assimilatory nitrate reductase [NAD(P)H] from Ankistrodesmus braunii.

    PubMed

    de la Rosa, M A; Diez, J; Vega, J M; Losada, M

    1980-05-01

    Assimilatory nitrate reductase [NAD(P)H] (EC 1.6.6.2) from Ankistrodesmus braunii has been purified to homogeneity by a simple procedure that utilizes as the main step affinity chromatography on Blue-Sepharose. The best enzyme preparation has a specific activity of 61.25 units/mg protein. The enzyme has a sedimentation coefficient of 10.9 S by sucrose-density-gradient centrifugation, and a Stokes radius of 9.8 nm was estimated by gel filtration techniques. Its molecular weight is 460000, but only one single band of 58000 was detected after sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The native enzyme seems thus to be composed of eight subunits. The nitrate reductase absorption spectrum shows wavelengths maxima at 280 and 416 nm and a broad shoulder at 450 nm. Reduced enzyme shows maxima at 424 (Soret), 527 (beta) and 557 (alpha) nm, and a bleaching at 450 nm. The reduced extracted heme chromophore, in pyridine and KOH, shows absorption bands at 414, 522 and 552 nm. These properties indicate the presence of a b-type cytochrome and flavin as prosthetic groups of A. braunii nitrate reductase. A minimum of four molecules of heme has been calculated per molecule of the enzyme complex. Redox titration of the enzyme shows a midpoint potential for the heme of -73 mV at pH 7.0. In the presence of p-hydroxymercuribenzoate, which inhibits the NAD(P)H-dependent activities of the complex, the enzyme-bound heme can be reduced with dithionite, but not with NAD(P)H. PMID:7200426

  9. Plasmodesmata of brown algae.

    PubMed

    Terauchi, Makoto; Nagasato, Chikako; Motomura, Taizo

    2015-01-01

    Plasmodesmata (PD) are intercellular connections in plants which play roles in various developmental processes. They are also found in brown algae, a group of eukaryotes possessing complex multicellularity, as well as green plants. Recently, we conducted an ultrastructural study of PD in several species of brown algae. PD in brown algae are commonly straight plasma membrane-lined channels with a diameter of 10-20 nm and they lack desmotubule in contrast to green plants. Moreover, branched PD could not be observed in brown algae. In the brown alga, Dictyota dichotoma, PD are produced during cytokinesis through the formation of their precursor structures (pre-plasmodesmata, PPD). Clustering of PD in a structure termed "pit field" was recognized in several species having a complex multicellular thallus structure but not in those having uniseriate filamentous or multiseriate one. The pit fields might control cell-to-cell communication and contribute to the establishment of the complex multicellular thallus. In this review, we discuss fundamental morphological aspects of brown algal PD and present questions that remain open. PMID:25516500

  10. Ecology of Harmful Algae

    Microsoft Academic Search

    Daniel L. Roelke

    2007-01-01

    Edna Graneli and Jefferson T. Turner, Editors;Ecological Studies Series, Vol. 189; Springer; ISBN 3540322094; 413 pp.; 2006; $195 Harmful algal blooms (HABs) affect commercially and recreationally important species, human health, and ecosystem functioning. Hallmark events are the visually stunning blooms where waters are discolored and filled with ichthyotoxin-producing algae that lead to large fish kills. Of most concern, however, are

  11. 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

  12. Sustainable biofuels from algae

    Microsoft Academic Search

    Michael Armin Borowitzka; Navid Reza Moheimani

    There is currently great interest in microalgae as sources of renewable energy and biofuels. Many algae species have a high\\u000a lipid content and can be grown on non-arable land using alternate water sources such as seawater. This paper discusses in\\u000a detail the issue of sustainability of commercial-scale microalgae production of biofuels with particular focus on land, water,\\u000a nutrients (N and

  13. Algae fuel clean electricity generation

    Microsoft Academic Search

    1993-01-01

    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

  14. 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.

  15. The resource utilization of algae—Preparing coal slurry with algae

    Microsoft Academic Search

    Weidong Li; Weifeng Li; Haifeng Liu

    2010-01-01

    Nowadays, the occurrence of harmful algal blooms is increasing rapidly all over the world. However, the methods of resource utilization of algae are very few. In this study, we propose a new way to dispose algae, which is gasification of coal–algae slurry. Coal slurries prepared with algae were investigated, and gasification reactivity of coal–algae slurry was compared with that of

  16. Testing for Toxic Algae By Tadd Barrow

    E-print Network

    Nebraska-Lincoln, University of

    Testing for Toxic Algae By Tadd Barrow UNL Extension Educator, Water Quality Algae is a microscopic plant that occurs in all water. However, only certain conditions bring algae to the surface, making it toxic to animals, especially humans and dogs. Toxic algae often are naturally occurring from high

  17. The Harmful Algae Page

    NSDL National Science Digital Library

    Woods Hole Oceanographic Institute. National Office for Marine Biotoxins and Harmful Algal Blooms .

    1997-01-01

    Produced by the National Office of Marine Biotoxins and Harmful Algal Blooms and housed at the Woods Hole Oceanographic Institution, this site covers the dark side of the organisms that provide the foundation for almost all marine life. The site focuses on the small number of algae that produce potent neurotoxins that "can be transferred through the food web where they affect and even kill the higher forms of life such as zooplankton, shellfish, fish, birds, marine mammals, and even humans that feed either directly or indirectly on them." The site is divided into the following sections: photos of "Red Tide" blooms, species responsible for harmful effects, adverse impacts at higher trophic levels, human illness associated with algal blooms, and effects in your region. Researchers, educators, and people with interests in such recent headline topics such as the Pfiesteria scare can all find useful information at this site.

  18. Obtaining Synchronous Cultures of Algae

    Microsoft Academic Search

    W. A. Glooschenko; H. Curl

    1968-01-01

    A COMMUNICATION from Lafeber and Steenbergen1 described a ``simple device for obtaining synchronous cultures of algae''. They stated that Scenedesmus obliquus, Ankistrodesmus falcatus, and Chlorella vulgaris all underwent synchronous cell division induced by the photo-period used.

  19. 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

  20. Seastars on Algae Covered Cobbles and Boulders

    USGS Multimedia Gallery

    Digital still photograph from Massachusetts Bay near Cohasset, MA, showing seastars (Asterias sp.), blood stars (Henricia sanguinolenta), blood drop tunicates (Dendrodoa carnea), mussels, and barnacles on cobbles and boulders covered with bubblegum algae and red filamentous algae.  Water d...

  1. Energy 101: Algae-to-fuels

    NSDL National Science Digital Library

    Erin R. Pierce

    This video is from the Energy 101 video series. It explains the process for converting micro-algae into fuel and makes the case that algae-based biofuels hold enormous potential for helping reduce our dependence on imported oil.

  2. Plant biomechanics: High-endurance algae

    NASA Astrophysics Data System (ADS)

    Carrington, Emily

    2013-11-01

    Breaking waves place repeated loading on marine algae, which can lead to death by fatigue. But observations of one alga suggest that its joint structure, which lacks transverse connections, confers fatigue resistance.

  3. School of Engineering and Science Algae Biofuels

    E-print Network

    Fisher, Frank

    School of Engineering and Science Algae Biofuels BY: Alessandro Faldi, Ph.D. Section Head is algae- based biofuels, which we believe could be a meaningful part of the energy mix in the future. Algae biofuels have potential to be an economically viable, low-net carbon transportation fuel

  4. RESEARCH ARTICLE Algae production on pig sludge

    E-print Network

    Boyer, Edmond

    RESEARCH ARTICLE Algae production on pig sludge Attila Bai & László Stündl & Péter Bársony & Milán- ied an economical method of algae production on pig sludge that can be operated on animal farms in Hungary with modest levels of investment. We analyzed four algae spe- cies, Chlorella vulgaris

  5. Reduced models of algae growth Heikki Haario,

    E-print Network

    Bardsley, John

    Reduced models of algae growth Heikki Haario, Leonid Kalachev Marko Laine, Lappeenranta University of the phenomena studied. Here, in the case of algae growth modelling, we show how a systematic model reduction may: Algae growth modelling, asymptotic methods, model reduction, MCMC, Adaptive Markov chain Monte Carlo. 1

  6. Indigenous algae for local bioresource production: Phycoprospecting

    Microsoft Academic Search

    Ann C. Wilkie; Scott J. Edmundson; James G. Duncan

    Photosynthetic algae represent a large and diverse group of organisms that have only a limited history of characterization and exploitation. The application of resource production from algae is relatively untapped, with the potential to produce fuels, food, fibers and nutraceuticals on a large scale. Methods to screen for indigenous species of algae have improved and can allow communities to prospect

  7. Notes from the Iberian Algae Belt

    Microsoft Academic Search

    Philip Cooke; Julie Porter; Hugo Pinto; Ana Rita Cruz; Fangzhu Zhang

    2011-01-01

    In this paper, we explore regional innovation in the use of varieties of algae as inputs to industrial processes. It is important to understand that algae are one of nature's most bountiful products, with an almost infinite variety of applications. Algae have received prominence in the research literature because of the strong evidence that they can make a major contribution

  8. Photobioreactors for mass cultivation of algae

    Microsoft Academic Search

    C. U. Ugwu; H. Aoyagi; H. Uchiyama

    2008-01-01

    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

  9. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Drugs 3 2012-04-01 2012-04-01 false Red algae. 184.1121 Section 184.1121 Food and...Specific Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  10. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Drugs 3 2011-04-01 2011-04-01 false Red algae. 184.1121 Section 184.1121 Food and...Specific Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  11. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Drugs 3 2013-04-01 2013-04-01 false Red algae. 184.1121 Section 184.1121 Food and...Specific Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  12. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Drugs 3 2010-04-01 2009-04-01 true Red algae. 184.1121 Section 184.1121 Food and...Specific Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  13. 21 CFR 184.1121 - Red algae.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Drugs 3 2014-04-01 2014-04-01 false Red algae. 184.1121 Section 184.1121 Food and...Specific Substances Affirmed as GRAS § 184.1121 Red algae. (a) Red algae are seaweeds of the species Gloiopeltis...

  14. Biotic interactions of marine algae

    Microsoft Academic Search

    Philippe Potin; Kamal Bouarab; Jean-Pierre Salaün; Georg Pohnert; Bernard Kloareg

    2002-01-01

    Marine algae encompass lineages that diverged about one billion years ago. Recent results suggest that they feature natural immunity traits that are conserved, as well as others that appear to be phylum- or environment-specific. In particular, marine plants resemble terrestrial plants and animals in their basic mechanisms for pathogen recognition and signaling, suggesting that these essential cell functions arose in

  15. 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 rather than from glycolate are consistent with the concept of an incomplete glycolate pathway in algae. PMID:6045296

  16. [A review on algae ecology in wetland].

    PubMed

    Xiong, Li; Xie, Liqiang; Sheng, Xiumei; Wu, Zhenbin; Xia, Yicheng

    2003-06-01

    The research advance in algae ecology in wetland was introduced in this paper, which included the algae population structure and its function, and the algae productivity and its affecting factors. Almost all kinds of algae occurred in wetland, including four assemblages: epipelon, epiphyton, metaphyton and phytoplankton, among which, diatom, green and blue algae were the predominant species. Algae were the fundamental players in the physical, chemical and biological processes that characterized wetland ecosystems. Most obvious was their role as primary producers and their place in the wetland food web. Algae were an important food resource for herbivores, and contributed to wetland nutrient cycle as the sources of dissolved organic matter and N. They could also be used as biomarkers for monitoring environment pollution. The affecting factors on algae's productivity were hydraulic factor, nutrition, temperature, illumination, herbivores and some other animals, and so on. Because of their functions in wetland, future research on algae in wetland should expand our knowledge of the environmental controls on algal biomass, productivity, and species composition in wetlands with particular in areas for which knowledge was incomplete. Included among these, may be a detailed evaluation of the proportionate contributions by epipelon, epiphyton, metaphyton, and phytoplankton to food web dynamics in wetlands, and a further study of the genetic technique in controlling hazardous algae. PMID:12974016

  17. 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.

  18. Halophilic-blue-green algae

    Microsoft Academic Search

    Thomas D. Brock

    1976-01-01

    The isolation of a halophilic blue-green alga, Aphanothece halophytica, from Great Salt Lake is described. The organism was cultured from waters with salinities up to saturated NaCl (about 30% w\\/v). It has an optimum salinity for growth of about 16% NaCl, but can grow very slowly even in saturated NaCl. Based on the study of the Great Salt Lake organism,

  19. Algae control for hydrogeneration canals

    SciTech Connect

    Grahovac, P.

    1997-02-16

    The purpose of this Cooperative Research and Development Agreement (CRADA) was to assess and develop control practices for nuisance algae growth in power canal that delivers water to hydro-generation facilities. This growth results in expenditures related not only to lost generation but also labor and materials costs associated with implementing remediation procedures. On an industry-wide basis these costs associated with nuisance algal growth are estimated to be several million dollars per year.

  20. 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. PMID:24845347

  1. Importance of algae oil as a source of biodiesel

    Microsoft Academic Search

    Ayhan Demirbas; M. Fatih Demirbas

    2011-01-01

    Algae are the fastest-growing plants in the world. Industrial reactors for algal culture are open ponds, photobioreactors and closed systems. Algae are very important as a biomass source. Algae will some day be competitive as a source for biofuel. Different species of algae may be better suited for different types of fuel. Algae can be grown almost anywhere, even on

  2. Red algae and their use in papermaking.

    PubMed

    Seo, Yung-Bum; Lee, Youn-Woo; Lee, Chun-Han; You, Hack-Chul

    2010-04-01

    Gelidialian red algae, that contain rhizoidal filaments, except the family Gelidiellaceae were processed to make bleached pulps, which can be used as raw materials for papermaking. Red algae consist of rhizoidal filaments, cortical cells usually reddish in color, and medullary cells filled with mucilaginous carbohydrates. Red algae pulp consists of mostly rhizoidal filaments. Red algae pulp of high brightness can be produced by extracting mucilaginous carbohydrates after heating the algae in an aqueous medium and subsequently treating the extracted with bleaching chemicals. In this study, we prepared paper samples from bleached pulps obtained from two red algae species (Gelidium amansii and Gelidium corneum) and compared their properties to those of bleached wood chemical pulps. PMID:20022488

  3. Algae production for energy and foddering

    Microsoft Academic Search

    Attila Bai; Péter Jobbágy; Emília Durkó

    This study not only presents the results of our own experiments in alga production, but also shows the expected economic results\\u000a of the various uses of algae (animal feed, direct burning, pelleting, bio-diesel production), the technical characteristics\\u000a of a new pelleting method based on literature, and also our own recommended alga production technology. In our opinion, the\\u000a most promising alternative

  4. Maximum carbon isotope fractionation in photosynthesis by blue-green algae and a green alga

    Microsoft Academic Search

    Joseph W. Pardue; Richard S. Scalan; Chase van Baalen; Patrick L. Parker

    1976-01-01

    The maximum carbon isotope fractionation occurring in photosynthetic fixation of carbon dioxide in pure cultures of blue-green algae was -23.9%. and for a green alga was -22.6%., Maximum fractionations were obtained where cell densities were low and carbon dioxide concentrations were greater than 0.5%. Fractionation was reduced at higher temperatures using a thermophilic blue-green alga. For filamentous blue-green algae wherein

  5. Indirect effects of algae on coral: algae-mediated, microbe-induced coral mortality

    Microsoft Academic Search

    Jennifer E. Smith; Morrigan Shaw; Rob A. Edwards; David Obura; Olga Pantos; Enric Sala; Stuart A. Sandin; Steven Smriga; Mark Hatay; Forest L. Rohwer

    2006-01-01

    Declines in coral cover are generally associated with increases in the abundance of fleshy algae. In many cases, it remains unclear whether algae are responsible, directly or indirectly, for coral death or whether they simply settle on dead coral surfaces. Here, we show that algae can indirectly cause coral mortality by enhancing microbial activity via the release of dissolved compounds.

  6. BOTANICAL BRIEFING Streptophyte algae and the origin of embryophytes

    E-print Network

    BOTANICAL BRIEFING Streptophyte algae and the origin of embryophytes Burkhard Becker* and Birger March 2009 Background Land plants (embryophytes) evolved from streptophyte green algae, a small group of freshwater algae ranging from scaly, unicellular flagellates (Mesostigma) to complex, filamentous thalli

  7. Microalgae Cultivation using Offshore Membrane Enclosures for Growing Algae (OMEGA)

    E-print Network

    Wiley, Patrick Edward

    2013-01-01

    biodiesel and biogas from algae: A review of process train options. WaterBiodiesel and Biogas from Algae: A Review of Process Train Options. Waterbiodiesel and biogas from algae: A review of process train options. Water

  8. FAS4932: ALGAE BIOLOGY AND ECOLOGY Instructor: Professor Edward Phlips

    E-print Network

    Watson, Craig A.

    reefs, rocky intertidal), their impacts (e.g. harmful algae blooms, food webs), and their applicationsFAS4932: ALGAE BIOLOGY AND ECOLOGY Instructor: Professor Edward Phlips Main Office: Program algae, including evolution, classification, structure, photosynthesis, growth, and reproduction

  9. Algal food selection and digestion by larvae of the pestiferous chironomid Chironomus Crassicaudatus under laboratory conditions.

    PubMed

    Frouz, Jan; Ali, Arshad; Lobinske, Richard J

    2004-12-01

    Feeding preference of Chironomus crassicaudatus 4th instars when fed on 5 algal species, Anabaena flos-aquae, Botryococcus braunii, Lyngbia cf. aeruginosa, Microcystis sp., and Scenedesmus quadricauda was studied under laboratory conditions. The various algal species were mixed in pairs at 1:1 ratio (fresh weight) to create 10 possible test combinations. The larvae were allowed to feed individually for 8 h on each algal mixture in tissue culture plates having 4 replicates. Four identical algal mixtures were simultaneously used without larvae as controls. After feeding, larvae and excrement were removed, and remaining algae from feeding trials and controls were fixed with Lugol's solution; the final ratio of algal species in each mixture was determined microscopically. Feeding preferences of C. crassicaudatus early 4th instars, in descending order, was L. cf. aeruginosa, A. flos-aquae, B. braunii, Microcystis sp., and S. quadricaudata. To evaluate algal digestibility, larval excrement was collected and the proportion of live and dead cells was determined by microscopic observations with the use of visible and ultraviolet light (epifluorescence). Anabaena flos-aquae and L. cf. aeruginosa were the easiest to digest, followed by Microcystis sp. and S. quadricaudata, whereas no digestion of B. braunii was observed. Cultures of larval excrement revealed the presence of some viable cells of all 5 tested algal species. PMID:15669393

  10. Common benthic algae and cyanobacteria in southern California tidal wetlands

    E-print Network

    Janousek, Christopher N

    2011-01-01

    Algae and cyanobacteria of southern California marine wetlands. Oscillatoria sp. 1 Filamentous,filamentous genera. A phylogenetically- diverse assemblage of pennate and centric diatoms, euglenoids, green algae,

  11. Use of algae as biofuel sources

    Microsoft Academic Search

    Ayhan Demirbas

    2010-01-01

    The aim of this study is to investigate the algae production technologies such as open, closed and hybrid systems, production costs, and algal energy conversions. Liquid biofuels are alternative fuels promoted with potential to reduce dependence on fossil fuel imports. Biofuels production costs can vary widely by feedstock, conversion process, scale of production and region. Algae will become the most

  12. FACTORS INFLUENCING METAL ACCUMULATION BY ALGAE

    EPA Science Inventory

    Shallow beds of algae (algal meanders) have proved to be highly effective at removing heavy metals and organometallics from lead-zinc mine and mill wastes. A research program was initiated (1) to determine conditions under which algae were most effective at concentrating signific...

  13. Commercial aspects of high intensity algae culture

    Microsoft Academic Search

    J. T. Patton; P. F. Phelan; G. L. Mauldin

    1981-01-01

    Conceptual designs for a commercial algae farm and an alcohol plant have been developed and an economic analysis performed. Algae would be grown and harvested continuously; the cells would be degraded by enzymatic hydrolysis and fermented to produce ethanol, concentrated to 190 proof by distillation. The protein recovered from the biomass residue and from the still bottoms would be sold

  14. 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.

  15. Sonic cracking of blue-green algae

    Microsoft Academic Search

    Spiros Kotopoulis; Antje Schommartz; Michiel Postema

    2009-01-01

    Algae are aquatic organisms classified separately from plants. They are known to cause many hazards to humans and the environment. Algae strands contain nitrogen-producing cells that help them float (heterocysts). It is hypothesized that if the membranes of these cells are disrupted by means of ultrasound, the gas may be released analogous to sonic cracking, causing the strands to sink.

  16. Antarctic sea ice thickness affects algae populations

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-01-01

    In the waters off Antarctica, algae grow and live in the sea ice that surrounds the southern continent—a floating habitat sure to change as the planet warms. As with most aquatic ecosystems, microscopic algae form the base of the Southern Ocean food web. Distinct algae populations reside in the sea ice surface layers, on the ice's underside, and within the floating ice itself. The algae that reside on the floating ice's underside are particularly important for the region's krill population, while those on the interior or surface layers are less accessible. Understanding how changing sea ice properties will affect the regional biology, then, depends on understanding how algae populations interact with the ice.

  17. 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. PMID:22634258

  18. Analysis of Land Suitable for Algae State of Hawaii

    E-print Network

    Analysis of Land Suitable for Algae Production State of Hawaii Prepared by Mele Chillingworth Scott of Hawaii at Manoa August 2011 #12;i Executive Summary Algae are considered to be a viable crop for biofuel for biofuels has increased interest in growing algae in Hawaii for biofuels. An analysis of algae production

  19. Aridity and Algae: Biodiesel Production in Arizona Jenna Bloxom

    E-print Network

    Fay, Noah

    Aridity and Algae: Biodiesel Production in Arizona Jenna Bloxom Advisor: Dr. Scott Whiteford Center resources. Often excluded from the typical water- related concerns associated with biofuels as algae as the best location in the world to grow algae, the state of Arizona is now home to several premier algae

  20. Triassic origin and early radiation of multicellular volvocine algae

    E-print Network

    Triassic origin and early radiation of multicellular volvocine algae Matthew D. Herron1 , Jeremiah-studied ETIs is the origin of multicellularity in the green alga Volvox, a model system for the evolution occurred dozens of times independently, for example in the red algae, brown algae, land plants, animals

  1. CEC-500-2010-FS-001 Algae OMEGA

    E-print Network

    CEC-500-2010-FS-001 Algae OMEGA (Offshore Membrane Enclosures For Growing Algae) TRANSPORTATION conditions but, to date, there are no algae cultivation methods on land that meet these requirements of scale will demonstrate the feasibility of NASA Ames's Offshore Membrane Enclosures for Growing Algae (OMEGA) system

  2. Conversion of solar energy to liquid fuels via algae

    Microsoft Academic Search

    J. T. Patton; G. L. Mauldin; P. F. Phelan

    1980-01-01

    Conceptual designs for a commercial algae farm and alcohol plant are presented in this paper. The designs envision algae being grown in shallow basins and being harvested continuously. The algae would then be degraded by enzymatic hydrolysis and fermented to produce alcohol which would be concentrated to 190 proof by distillation. Protein from the algae would be a valuable by-product

  3. Seeing Toxic Algae Before it Blooms By Steve Ress

    E-print Network

    Nebraska-Lincoln, University of

    of toxic blue-green algae before the bacteria that produce it can grow into a full-scale bloom. Now UNL and monitor in real-time, the water-borne agents that can cause toxic blue- green algae to flourish and become Technologies (CALMIT) can see algae pigments, such as chlorophyll and cyanobacteria that blue-green algae

  4. Method and apparatus for processing algae

    DOEpatents

    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.

  5. 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 consequences of our actions, and we saw for ourselves how we are polluting and killing the environment. Releasing excess nutrients into our waterways is creating a destructive chain reaction, but if we monitor our output of pollution, we can minimize the amount of damage we do to algae, organisms, and the environment in general.

  6. Biosystematics of the cryptogamic flora of New Zealand: Algae

    Microsoft Academic Search

    M. J. Parsons

    1985-01-01

    The groups of organisms included in the algae and their extensive diversity are discussed. The algae of New Zealand can be divided into three main ecological-morphological groups: the freshwater algae of which we have about 2080 species, the marine micro-algae with approximately 700 species and the marine macro-algae, the best known group, with about 900 species.The present knowledge of the

  7. A comparative study of fossil and extant algaenans using ruthenium tetroxide degradation

    NASA Astrophysics Data System (ADS)

    Blokker, Peter; Schouten, Stefan; de Leeuw, Jan W.; Sinninghe Damsté, Jaap S.; van den Ende, Herman

    2000-06-01

    In this study the chemical structure of algaenans isolated from the freshwater algae Tetraedron minimum, Pediastrum boryanum and Botryococcus braunii are compared with their fossil counterparts by means of RuO 4 oxidation. The results show that the algaenans investigated are preserved in sediments with only minor structural alterations. However, product mixtures from RuO 4 degradation of the fossil algaenans exhibit a broader distribution of oxidation products than freshly isolated algaenans indicating that the fossil biopolymers contain a greater proportion of ether cross-links, which maybe an effect of diagenetic alteration or different algal strains. Despite these differences, fossil algaenans can still be recognised chemically on the basis of the specific RuO 4 oxidation products, even after 50 Ma of sediment burial.

  8. Extraction of lipids from microalgae using CO2-expanded methanol and liquid CO2.

    PubMed

    Paudel, Ashok; Jessop, Michael J; Stubbins, Spencer H; Champagne, Pascale; Jessop, Philip G

    2015-05-01

    The use of CO2-expanded methanol (cxMeOH) and liquid carbon dioxide (lCO2) is proposed to extract lipids from Botryococcus braunii. When compressed CO2 dissolves in methanol, the solvent expands in volume, decreases in polarity and so increases in its selectivity for biodiesel desirable lipids. Solid phase extraction of the algal extract showed that the cxMeOH extracted 21 mg of biodiesel desirable lipids per mL of organic solvent compared to 3mg/mL using either neat methanol or chloroform/methanol mixture. The non-polar lCO2 showed a high affinity for non-polar lipids. Using lCO2, it is possible to extract up to 10% neutral lipids relative to the mass of dry algae. Unlike extractions using conventional solvents, these new methods require little to no volatile, flammable, or chlorinated organic solvents. PMID:25537138

  9. Biogas production experimental research using algae.

    PubMed

    Baltr?nas, Pranas; Misevi?ius, 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. PMID:25859392

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

    Microsoft Academic Search

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

    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 reuse, as algae can be grown using CO emissions from fossil-based energy generation. Moreover,

  11. 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. PMID:19544699

  12. 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. PMID:16414751

  13. Turning Algae into Energy in New Mexico

    ScienceCinema

    Sayre, Richard; Olivares, Jose; Lammers, Peter

    2014-06-24

    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.

  14. Genome of the red alga Porphyridium purpureum

    PubMed Central

    Bhattacharya, Debashish; Price, Dana C.; Xin Chan, Cheong; Qiu, Huan; Rose, Nicholas; Ball, Steven; Weber, Andreas P. M.; Cecilia Arias, Maria; Henrissat, Bernard; Coutinho, Pedro M.; Krishnan, Anagha; Zäuner, Simone; Morath, Shannon; Hilliou, Frédérique; Egizi, Andrea; Perrineau, Marie-Mathilde; Yoon, Hwan Su

    2013-01-01

    The limited knowledge we have about red algal genomes comes from the highly specialized extremophiles, Cyanidiophyceae. Here, we describe the first genome sequence from a mesophilic, unicellular red alga, Porphyridium purpureum. The 8,355 predicted genes in P. purpureum, hundreds of which are likely to be implicated in a history of horizontal gene transfer, reside in a genome of 19.7?Mbp with 235 spliceosomal introns. Analysis of light-harvesting complex proteins reveals a nuclear-encoded phycobiliprotein in the alga. We uncover a complex set of carbohydrate-active enzymes, identify the genes required for the methylerythritol phosphate pathway of isoprenoid biosynthesis, and find evidence of sexual reproduction. Analysis of the compact, function-rich genome of P. purpureum suggests that ancestral lineages of red algae acted as mediators of horizontal gene transfer between prokaryotes and photosynthetic eukaryotes, thereby significantly enriching genomes across the tree of photosynthetic life. PMID:23770768

  15. Genome of the red alga Porphyridium purpureum.

    PubMed

    Bhattacharya, Debashish; Price, Dana C; Chan, Cheong Xin; Qiu, Huan; Rose, Nicholas; Ball, Steven; Weber, Andreas P M; Arias, Maria Cecilia; Henrissat, Bernard; Coutinho, Pedro M; Krishnan, Anagha; Zäuner, Simone; Morath, Shannon; Hilliou, Frédérique; Egizi, Andrea; Perrineau, Marie-Mathilde; Yoon, Hwan Su

    2013-01-01

    The limited knowledge we have about red algal genomes comes from the highly specialized extremophiles, Cyanidiophyceae. Here, we describe the first genome sequence from a mesophilic, unicellular red alga, Porphyridium purpureum. The 8,355 predicted genes in P. purpureum, hundreds of which are likely to be implicated in a history of horizontal gene transfer, reside in a genome of 19.7 Mbp with 235 spliceosomal introns. Analysis of light-harvesting complex proteins reveals a nuclear-encoded phycobiliprotein in the alga. We uncover a complex set of carbohydrate-active enzymes, identify the genes required for the methylerythritol phosphate pathway of isoprenoid biosynthesis, and find evidence of sexual reproduction. Analysis of the compact, function-rich genome of P. purpureum suggests that ancestral lineages of red algae acted as mediators of horizontal gene transfer between prokaryotes and photosynthetic eukaryotes, thereby significantly enriching genomes across the tree of photosynthetic life. PMID:23770768

  16. Algae control problems and practices workshop

    SciTech Connect

    Pryfogle, P.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Ghio, G. [Pacific Gas and Electric Co., San Francisco, CA (United States)

    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.

  17. Introduction slide 2 Biofuels and Algae Markets, Systems,

    E-print Network

    Introduction slide 2 Biofuels and Algae Markets, Systems, Players and Commercialization Outlook http://www.emerging-markets.com Consultant, Global Biofuels Business Development Author, Biodiesel 2020: A Global Market Survey (2008) Algae 2020: Biofuels Commercialization Outlook (2009) Columnist, Biofuels

  18. ALGAE BLOOMS AND PHOSPHORUS LOADING IN LAKE LOWELL, IDAHO

    EPA Science Inventory

    Algae blooms limit recreational use of Lake Lowell, ID (17050114) by reducing water clarity and esthetic qualities. Under bloom conditions, algae have a negative impact on the reservoir fishery because of periodic oxygen depletion associated with respiration and decomposition. ...

  19. 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...

  20. Cognome e nome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 2 febbraio 2012 Compitino (2 ore)

    E-print Network

    Robbiano, Lorenzo

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 2 febbraio 2012­ Compitino (2 ore) Giustificare ogni affermazione Salvare il file CoCoA come

  1. Cognome e nome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 14 novembre 2011 Compitino (2 ore)

    E-print Network

    Robbiano, Lorenzo

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 14 novembre 2011­ Compitino (2 ore) Giustificare ogni affermazione Salvare il file CoCoA come

  2. A golden opportunity: Researchers making progress in understanding toxic algae 

    E-print Network

    Wythe, Kathy

    2008-01-01

    tx H2O | pg. 20 cientists at three Texas universities investigating golden algae, its explosive growth, and its deadly toxins have dis- covered an apparent competition between golden algae and blue green algae in certain Texas lakes...) Scientists researching golden algae, its explosive growth, and possible management strategies have studied the affects of nutrients such as nitrate and phosphate have on control- ling the organism. tx H2O | pg. 22 ents, and low salinity that stress...

  3. Life cycle analysis of algae biodiesel

    Microsoft Academic Search

    Kyle Sander; Ganti S. Murthy

    2010-01-01

    Background, aim, and scope  Algae biomass has great promise as a sustainable alternative to conventional transportation fuels. In this study, a well-to-pump\\u000a life cycle assessment (LCA) was performed to investigate the overall sustainability and net energy balance of an algal biodiesel\\u000a process. The goal of this LCA was to provide baseline information for the algae biodiesel process.\\u000a \\u000a \\u000a \\u000a \\u000a Materials and methods  The functional

  4. Environmental Life Cycle Comparison of Algae to Other Bioenergy

    E-print Network

    Clarens, Andres

    Environmental Life Cycle Comparison of Algae to Other Bioenergy Feedstocks A N D R E S F . C L A R December 6, 2009. Accepted December 15, 2009. Algae are an attractive source of biomass energy since. In spite of these advantages, algae cultivation has not yet been compared with conventional crops from

  5. Analysis of Land Suitable for Algae State of Hawaii

    E-print Network

    Analysis of Land Suitable for Algae Production State of Hawaii Prepared for the U.S. Department agency thereof. #12;Analysis of Land Suitable for Algae Production State of Hawaii Prepared by Mele University of Hawaii at Manoa August 2011 #12;i Executive Summary Algae are considered to be a viable crop

  6. CORALLINE ALGA STANDS THE TEST OF TIME ON SHORELINE

    E-print Network

    Martone, Patrick T.

    Inside JEB i CORALLINE ALGA STANDS THE TEST OF TIME ON SHORELINE No one likes getting bashed about, the coralline algae, which have calcified most of their cells and essentially turned themselves into living, and thus most of force, occurring at the small joints (they make up just 15% of the alga), Denny wondered

  7. Intracellular invasion of green algae in a salamander host

    E-print Network

    Intracellular invasion of green algae in a salamander host Ryan Kerneya,1 , Eunsoo Kimb , Roger P) and green algae ("Oophila amblystomatis" Lamber ex Printz) has been considered an ectosymbiotic mutu- alism tracts, consistent with oviductal transmission of algae from one salamander generation to the next

  8. Sedimentation of algae: relationships with biomass and size distribution1

    E-print Network

    Mazumder, Asit

    Sedimentation of algae: relationships with biomass and size distribution1 Isabelle Larocque, A distribution of epilimnetic algae on patterns of algal sedimentation was determined in lake enclosures under the mean length of algae in fish-free enclosures and reduced the mean length in the enclosures to which

  9. A Realistic Technology and Engineering Assessment of Algae Biofuel Production

    E-print Network

    Quinn, Nigel

    A Realistic Technology and Engineering Assessment of Algae Biofuel Production T the feasibility of largescale algae biofuel production. Contents of the Report Chapter 1 introduces microalgae consumption (about 200 billion gallons per year), renewable algae oil could be a major contributor to biofuel

  10. Development of suitable photobioreactor for algae production – A review

    Microsoft Academic Search

    R. N. Singh; Shaishav Sharma

    2012-01-01

    Microalgal species are recently in the spotlight for biofuels production like biodiesel, bioethanol and biohydrogen. Algae are also used as a biofertiliser, source of nutrient and for controlling pollution. Algae being a photosynthetic organism are produced in the photo bioreactors. Hence the design and development of photobioreactors for maximum production of algae is very important. Apart from maximum production, other

  11. The origin of red algae and the evolution of chloroplasts

    Microsoft Academic Search

    David Moreira; Hervé Le Guyader; Hervé Philippe

    2000-01-01

    Chloroplast structure and genome analyses support the hypothesis that three groups of organisms originated from the primary photosynthetic endosymbiosis between a cyanobacterium and a eukaryotic host: green plants (green algae + land plants), red algae and glaucophytes (for example, Cyanophora). Although phylogenies based on several mitochondrial genes support a specific green plants\\/red algae relationship, the phylogenetic analysis of nucleus-encoded genes

  12. Global Dynamics of Zooplankton and Harmful Algae in Flowing Habitats

    E-print Network

    Hsu, Sze-Bi

    of harmful algal blooms in riverine ecosystems. It is important to un- derstand the persistence of algaeGlobal Dynamics of Zooplankton and Harmful Algae in Flowing Habitats Sze-Bi Hsu Feng-Bin Wang Xiao from the dynamics of harmful algae and zooplankton in flowing- water habitats where a main channel

  13. 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. PMID:24496987

  14. The Correlation of Soil Algae, Airborne Algae, and Fern Spores with Meteorological Conditions on the Island of Hawaii I

    Microsoft Academic Search

    L. CARSON; R. MALCOLM BROWN

    Cor relations of the generic diversity of soil and airborne algae with altitude on the island of Hawaii are noted. D istribution of the soil algae was deter­ mine d by culturi ng an aqueous soil extract fro m designated altitudes on aga rized inorganic growth media. Distribution of air borne algae and fern spores was deter­ mined by investigations

  15. HARMFUL ALGAE POSE ADDITIONAL CHALLENGES FOR OYSTER RESTORATION: IMPACTS OF THE HARMFUL ALGAE KARLODINIUM VENEFICUM AND PROROCENTRUM

    E-print Network

    North, Elizabeth W.

    HARMFUL ALGAE POSE ADDITIONAL CHALLENGES FOR OYSTER RESTORATION: IMPACTS OF THE HARMFUL ALGAE been increasing over the past half century, leading to increases in hypoxia and harmful algal blooms difficult. KEY WORDS: oysters, larvae, harmful algae, HABs, Chesapeake Bay, oyster restoration, Karlodinium

  16. Molecular biotechnology of marine algae in China

    Microsoft Academic Search

    Song Qin; Peng Jiang; Cheng-Kui Tseng

    2004-01-01

    Molecular biotechnology of marine algae is referred to as the biotechnology on the identification, modification, production and utilization of marine algal molecules. It involves not only the manipulation of macromolecules such as DNA, RNA and proteins, but also deals with low molecular weight compounds such as secondary metabolites.

  17. 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)

  18. Biofuels from algae for sustainable development

    Microsoft Academic Search

    M. Fatih Demirbas

    2011-01-01

    Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and useful chemicals. Two algae samples (Cladophora fracta and Chlorella protothecoid) were studied for biofuel production. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global

  19. Alkanes and alkenes in marine benthic algae

    Microsoft Academic Search

    W. W. Youngblood; M. Blumer

    1973-01-01

    Saturated and olefinic hydrocarbons were determined in additional species of benthic marine algae from the Cape Cod (Massachusetts, USA) area (see: Youngblood et al., 1971). The distribution of homologous and isomeric olefins was studied in plants of different age and in morphologically different parts of the same specimen. With two minor exceptions, only normal alkanes and alkenes are present. The

  20. Biosolar production of fuels from algae

    Microsoft Academic Search

    T. W. Jeffries; P. H. Moulthrop; H. Timourian; R. L. Ward; B. J. Berger

    1976-01-01

    A design concept is described for the production of methane, hydrogen, and ammonia using solar energy. Filamentous, nitrogen-fixing blue-green algae are employed as a source of biomass for methane and ammonia generation by anaerobic digestion and as a biological catalyst for the photoproduction of hydrogen from water. The resources needed, biomass production and harvest, anaerobic digester, the process of biophotolysis,

  1. Indigenous algae: Potential factories for biodiesel production

    Microsoft Academic Search

    DM MAHARAJH; R LALLOO

    1. Abstract The environmental effects of burning fossil fuels and the increased crude oil prices have triggered increased interest in biofuels. Biodiesel is traditionally produced from oil seed crops, which have lower yields per land area and threaten food security when compared to algae which have high oil yields (~ 90 times more oil per area of land in comparison

  2. Biogeochemistry: Ancient algae crossed a threshold

    NASA Astrophysics Data System (ADS)

    Pancost, Richard D.; Badger, Marcus P. S.; Reinfelder, John

    2013-08-01

    The finding that the shells of certain algae can contain a signature of low levels of atmospheric carbon dioxide has prompted the discovery of the emergence of this signature in the fossil record. Here, experts discuss the implications of this for climate science and ocean ecology. See Letter p.558

  3. 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

  4. 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.

  5. Effect of triazine compounds on freshwater algae

    Microsoft Academic Search

    Salwa A. Shehata; M. A. El-Dib; Hoda F. Abou-Waly

    1993-01-01

    The continued input of pesticides into the aquatic environment possess a potential threat to the aquatic ecosystem by their direct action on aquatic flora. The killing of the algae in the aquatic habitat polluted with pesticides leads to disturbances in the primary food chain and ultimately to the ecosystem (Palmer 1980). Pollution of water with several classes of pesticides and

  6. The taxonomy of blue-green algae

    Microsoft Academic Search

    B. A. Whitton

    1969-01-01

    The conventions at present used in the classification of blue-green algae frequently prove unsatisfactory. A solution is suggested which requires the simultaneous use of two different approaches. When a binomial is essential the flora of Geitler (1932) should be adequate for most purposes, but any long term attempt to sort out the present chaos will require the use of numerical

  7. Changes in chloroplast structure in lichenized algae

    Microsoft Academic Search

    O. Peksa; P. Skaloud

    2008-01-01

    Chloroplast morphology represents a basic characteristic in the systematic classification of trebouxioid algae. However, in different ontogenetic, physiological and ecological stages chloroplasts may vary markedly. Various developmental states of two algal species (Asterochloris sp. and Trebouxia incrustata) isolated from four lichens (Cladonia foliacea, Lecidea fuscoatra, Lepraria sp., Xanthoparmelia conspersa) were examined by confocal microscopy for variations in chloroplast structure. Distinct

  8. Battling golden algae: Results suggest preventative lake managment approaches 

    E-print Network

    Supercinski, Danielle

    2011-01-01

    14 tx H2O Winter 2011 Story by Danielle Supercinski Battling golden algae Results suggest preventative lake management approaches Golden algae blooms, or the explosive growth of algae, are known to be toxic, but recent #28;ndings from... for golden algae. #22;e salinity has not gone back up from that year, and P. parvum is even further removed from its growth optimum.? Grover said when they #28;rst started this research, they had two important questions about golden algae. ?First, we had...

  9. Battling Golden Algae: Results suggest preventative lake management approaches 

    E-print Network

    Supercinski, Danielle

    2011-01-01

    14 tx H2O Winter 2011 Story by Danielle Supercinski Battling golden algae Results suggest preventative lake management approaches Golden algae blooms, or the explosive growth of algae, are known to be toxic, but recent #28;ndings from... for golden algae. #22;e salinity has not gone back up from that year, and P. parvum is even further removed from its growth optimum.? Grover said when they #28;rst started this research, they had two important questions about golden algae. ?First, we had...

  10. Toxic and deadly: Working to manage algae in Lake Granbury 

    E-print Network

    Wythe, Kathy

    2011-01-01

    Department (TPWD), scientists from three universities are investigating golden algae?s txH2O | pg. 10 Story by Kathy Wythe txH2O | pg. 11 explosive growth and deadly toxins. In research started at Lake Possum Kingdom and continuing at Lakes... the manipulation of hydrology, pH, or ammonia. The team is also investigating the influence of blue green algae on golden algae and the influence of aquatic plants on golden algae blooms. Recent research from this team was published in a dedicated volume...

  11. Toxic and deadly: Working to manage algae in Lake Granbury 

    E-print Network

    Wythe, Kathy

    2010-01-01

    Department (TPWD), scientists from three universities are investigating golden algae?s txH2O | pg. 10 Story by Kathy Wythe txH2O | pg. 11 explosive growth and deadly toxins. In research started at Lake Possum Kingdom and continuing at Lakes... the manipulation of hydrology, pH, or ammonia. The team is also investigating the influence of blue green algae on golden algae and the influence of aquatic plants on golden algae blooms. Recent research from this team was published in a dedicated volume...

  12. Glycolate Pathway in Green Algae 1

    PubMed Central

    Bruin, W. J.; Nelson, Edward B.; Tolbert, N. E.

    1970-01-01

    By three criteria, the glycolate pathway of metabolism is present in unicellular green algae. Exogenous glycolate-1-14C was assimilated and metabolized to glycine-1-14C and serine-1-14C. During photosynthetic 14CO2 fixation the distributions of 14C in glycolate and glycine were similar enough to suggest a product-precursor relationship. Five enzymes associated with the glycolate pathway were present in algae grown on air. These were P-glycolate phosphatase, glycolate dehydrogenase (glycolate:dichloroindophenol oxidoreductase), l-glutamate:glyoxylate aminotransferase, serine hydroxymethylase, and glycerate dehydrogenase. Properties of glycerate dehydrogenase and the aminotransferase were similar to those from leaf peroxisomes. The specific activity of glycolate dehydrogenase and serine hydroxymethylase in algae was 1/5 to 1/10 that of the other enzymes, and both these enzymes appear ratelimiting for the glycolate pathway. Labeling patterns for products of the glycolate pathway during 14CO2 fixation are not the same as those obtained with higher plants. In higher plants glycolate, glycine, and serine are uniformly labeled at shortest time periods. In algae, serine was predominately carboxyl-labeled, similarly to 3-phosphoglycerate. This result, plus the lower specific activity of serine hydroxymethylase, indicates that the glycine-serine interconversin in algae is slower than in plants. Initially (2 to 4 seconds) glycolate and glycine were more C-2 labeled. They rapidly became uniformly labeled, with glycine becoming uniformly labeled first. In the presence of isonicotinylhydrazide, labeled glycolate and glycine accumulated, and only a trace of serine-14C was detected. Then glycolate and glycine were initially carboxyl-labeled, and glycolate became uniformly labeled almost immediately and before glycine. These results suggest rapid metabolism of glycolate and glycine, in addition to the glycolate pathway. PMID:16657472

  13. 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. PMID:20042280

  14. 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. PMID:19560336

  15. 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

  16. Molecular biotechnology of marine algae in China

    Microsoft Academic Search

    Song Qin; Peng Jiang; Cheng-Kui Tseng

    \\u000a Molecular biotechnology of marine algae is referred to as the biotechnology on the identification, modification, production\\u000a and utilization of marine algal molecules. It involves not only the manipulation of macromolecules such as DNA, RNA and proteins,\\u000a but also deals with low molecular weight compounds such as secondary metabolites.\\u000a \\u000a \\u000a In the last decade, molecular systematic researches to investigate the relationship and

  17. Sequestration of CO2 by halotolerant algae

    PubMed Central

    2014-01-01

    The potential of halotolerant algae isolated from natural resources was used to study CO2 fixation and algal lipid production. Biological fixation of CO2 in photobioreactor in presence of salinity is exploited. The CO2 concentration 1060 ppm gave the highest biomass yield (700 mg dry wt/l), the highest total lipid content (10.33%) with 80% of CO2 removal. PMID:24847439

  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, especially in low phosphate regimes such as oligotrophic waters and late stage phytoplankton blooms.

  19. Energy from algae using microbial fuel cells

    Microsoft Academic Search

    Sharon B. Velasquez-Orta; Tom P. Curtis; Bruce E. Logan

    2009-01-01

    ABSTRACT: Bioelectricityproductionfromaphytoplankton, 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 producedmoreenergygeneration 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

  20. Prokaryotic algae associated with Australian proterozoic stromatolites.

    NASA Technical Reports Server (NTRS)

    Licari, G. R.; Cloud, P.

    1972-01-01

    The most favorable sites in which to study the associations between stromatolites and the algae responsible for them are places where a variety of stromatolites of possibly early diagenetic or primary silica occupy a layer of substantial thickness of little metamorphosed ancient sediments. One such place is in northwestern Queensland, Australia. Five cases of association between stromatolites and blue-green algal nannofossils were observed within a 100-m sequence of carbonate rocks in that area.

  1. Ammonia assimilation in blue-green algae

    Microsoft Academic Search

    A. H. Neilson; M. Doudoroff

    1973-01-01

    The occurrence of alanine dehydrogenase (AlaDH), glutamate dehydrogenase (GDH), and 2-ketoglutarate: glutamine amidotransferase (GGAT), has been surveyed in a number of blue-green algae. Among nine unicellular strains grown with nitrate, and belonging to five of the major typological groups, AlaDH was present in seven, and GDH in all eight that were assayed. In ten filamentous strains grown with nitrate, and

  2. Turbulent Boundary Layers over Filamentous Algae

    Microsoft Academic Search

    Michael P. Schultz

    1999-01-01

    Turbulent boundary layer measurements have been made on surfaces covered with filamentous marine algae. These experiments were conducted in a closed return water tunnel using a two-component, laser Doppler velocimeter (LDV). The axial and wall-normal turbulence intensities and Reynolds shear stress are compared with flows over smooth and conventional k-type rough walls. The results indicate that profiles of these turbulence

  3. Mass Production of Biodiesel From Algae UROP Summer 2008 Project Proposal

    E-print Network

    Minnesota, University of

    1 Mass Production of Biodiesel From Algae UROP Summer 2008 Project Proposal Steven A. Biorn Faculty energy products from algae. The first step in this process is to select species of algae with high growth of green algae. Once the oils have been extracted, the remnants of the algae contain protein, starches

  4. RESEARCH ARTICLE Open Access Origin of land plants: Do conjugating green algae

    E-print Network

    RESEARCH ARTICLE Open Access Origin of land plants: Do conjugating green algae hold the key? Sabina (embryophytes) evolved from streptophyte algae, also referred to as charophycean algae. The streptophyte algae are a paraphyletic group of green algae, ranging from unicellular flagellates to morphologically complex forms

  5. Interactions between corals and algae on a temperate zone rocky reef: mediation by sea urchins

    Microsoft Academic Search

    James A. Coyer; Richard F. Ambroseb; John M. Engle; Jay C. Carrolld

    1993-01-01

    Interactions among sea urchins, algae, and a scleractinian coral were examined in a lo-year study off Anacapa Island, California. Abundances of the solitary cup coral Balanophyllia elegans Verrill and per- cent cover of algae were inversely correlated. Corals could be killed due to overgrowth by kelp holdfasts, ephemeral filamentous algae, or encrusting coralline algae. Overgrowth by filamentous and coralline algae

  6. Biology and systematics of heterokont and haptophyte algae.

    PubMed

    Andersen, Robert A

    2004-10-01

    In this paper, I review what is currently known of phylogenetic relationships of heterokont and haptophyte algae. Heterokont algae are a monophyletic group that is classified into 17 classes and represents a diverse group of marine, freshwater, and terrestrial algae. Classes are distinguished by morphology, chloroplast pigments, ultrastructural features, and gene sequence data. Electron microscopy and molecular biology have contributed significantly to our understanding of their evolutionary relationships, but even today class relationships are poorly understood. Haptophyte algae are a second monophyletic group that consists of two classes of predominately marine phytoplankton. The closest relatives of the haptophytes are currently unknown, but recent evidence indicates they may be part of a large assemblage (chromalveolates) that includes heterokont algae and other stramenopiles, alveolates, and cryptophytes. Heterokont and haptophyte algae are important primary producers in aquatic habitats, and they are probably the primary carbon source for petroleum products (crude oil, natural gas). PMID:21652306

  7. Microplate Technique for Determining Accumulation of Metals by Algae

    PubMed Central

    Hassett, James M.; Jennett, J. Charles; Smith, James E.

    1981-01-01

    A microplate technique was developed to determine the conditions under which pure cultures of algae removed heavy metals from aqueous solutions. Variables investigated included algal species and strain, culture age (11 and 44 days), metal (mercury, lead, cadmium, and zinc), pH, effects of different buffer solutions, and time of exposure. Plastic, U-bottomed microtiter plates were used in conjunction with heavy metal radionuclides to determine concentration factors for metal-alga combinations. The technique developed was rapid, statistically reliable, and economical of materials and cells. Results (expressed as concentration factors) were in reasonably good agreement with literature values. All species of algae studied removed mercury from solution. Green algae proved better at accumulating cadmium than did blue-green algae. No alga studied removed zinc, perhaps because cells were maintained in the dark during the labeling period. Chlamydomonas sp. proved superior in ability to remove lead from solution. PMID:16345764

  8. Microplate technique for determining accumulation of metals by algae

    SciTech Connect

    Hassett, J.M.; Jennett, J.C.; Smith, J.E.

    1981-05-01

    A microplate technique was developed to determine the conditions under which pure cultures of algae removed heavy metals from aqueous solutions. Variables investigated included algal species and strain, culture age (11 and 44 days), metal (mercury, lead, cadmium, and zinc), pH, effects of different buffer solutions, and time of exposure. Plastic, U-bottomed microtiter plates were used in conjunction with heavy metal radionuclides to determine concentration factors for metal-alga combinations. The technique developed was rapid, statistically reliable, and economical of materials and cells. All species of algae studied removed mercury from solution. Green algae proved better at accumulating cadmium than did blue-green algae. No alga studied removed zinc, perhaps because cells were maintained in the dark during the labeling period. Chlamydomonas sp. proved superior in ability to remove lead from solution.

  9. Zooplankton Feeding on Differentially Labelled Algae and Bacteria

    Microsoft Academic Search

    Moshe Gophen; Ben Zion Cavari; Thomas Berman

    1974-01-01

    HERBIVOROUS zooplankton can graze on planktonic algae, bacteria and detrital particles1. Selective feeding of planktonic crustaceans on algae has been described and attributed to passive size selection by filtration or raptorial feeding1. The ingestion and utilisation of algae, bacteria and detritus by zooplankton has also been noted2-6 but as yet there have been few reports concerning the behaviour of zooplankton

  10. Cobra bite wound infection caused by Shewanella algae.

    PubMed

    Liu, Po-Yu; Shi, Zhi-Yuan; Shyu, Ching-Lin; Wu, Zong-Yen; Lai, Kuo-Lung; Chang, Chih-Yen; Chen, Ying-Ju; Huang, Jin-An; Mao, Yan-Chiao; Tung, Kwong-Chung

    2014-03-01

    Shewanella wound infections after snake bites are rare. We report the case of a Shewanella algae wound infection associated with a cobra bite in a 27-year-old woman. The isolate was confirmed by sequencing of the 16S ribosomal DNA gene. This case expands the reported spectrum of infection caused by S. algae and raises the possibility that S. algae could be a causative pathogen in wound infections resulting from snake bites. PMID:24602312

  11. Biosorption of lead and cadmium using marine algae

    Microsoft Academic Search

    Ramzy B. Nessim; Ahmad R. Bassiouny; Hermine R. Zaki; Madelyn N. Moawad; Kamal M. Kandeel

    2011-01-01

    The use of algae (Ulva fasciata, green and Sargassum sp., brown) to reduce lead and cadmium levels from mono-metal solutions was investigated. The brown algae showed higher efficiency for the accumulation of lead (?1.5 times) and cadmium (?2 times) than green algae. The optimum pH value is found to be between 4 and 5.5. Regarding biomass concentration, an increase in metals

  12. Effect of pesticides on blue-green algae

    Microsoft Academic Search

    P. K. Singh

    1973-01-01

    Effect of pesticides, i.e., Benzene Hexachloride, Lindane, Diazinon and Endrin that are often used in India was observed on nitrogen-fixing blue-green algae Cylindrospermum sp., Aulosira fertilissima Ghose and aerobically non-nitrogen-fixing blue-green alga Plectonema boryanum strain 594. These algae were sensitive for BHC in comparison to other pesticides. A. fertilissima and P. boryanum were more resistant than Cylindrospermum sp.

  13. Antimutagenic properties of fresh-water blue-green algae

    Microsoft Academic Search

    N. Lahitová; M. Doupovcová; J. Zvonár; J. Chandoga; G. Hocman

    1994-01-01

    The antimutagenic properties of whole fresh-water blue-green algaeAphanisomenon flos-aquae, marketed under the commercial name “Alpha Sun” were tested using the Ames test. Simultaneous addition of both algae and\\u000a Nitrovin (a mutagen) to the test medium did not reduce the mutagenic activity. On the other hand, addition of freeze-dried\\u000a blue-green algae to the test medium 2–24 h before the application of

  14. Taxonomy of blue-green algae-problems and prospects

    Microsoft Academic Search

    T. V. Desikachary

    1970-01-01

    Summary  Only in the past 10 years has attention again been focused on the blue-green algae. Physiological problems are doubtless the\\u000a main point of interest. However, aside from this, several specialists are studying the taxonomy of this group of algae; they\\u000a are unanimous in their conviction that the systematic of the blue-green algae must be revised with due consideration given\\u000a to

  15. Flotation of blue-green algae using methylated egg ovalbumin

    Microsoft Academic Search

    Hideo Maruyama; Hideshi Seki; Akira Suzuki

    2009-01-01

    The removal of blue-green algae by dispersed gas flotation was conducted. Methylated ovalbumin (MeOA) was used as frother and flocculant, which is a biodegradable substance. The continuous flotation experiments were conducted at different feed mass flow rate of the blue-green algae cells and MeOA. The operating variables were the mass flow rate of blue-green algae cell and MeOA, the initial

  16. 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. PMID:25537136

  17. Parachloroidium gen. nov. (Trebouxiophyceae, Chlorophyta), a novel genus of coccoid green algae from subaerial corticolous biofilms

    E-print Network

    Parachloroidium gen. nov. (Trebouxiophyceae, Chlorophyta), a novel genus of coccoid green algae. Parachloroidium gen. nov. (Trebouxiophyceae, Chlorophyta), a novel genus of coccoid green algae from subaerial the Parachloroidium strains from other similar green algae. However, ultrastructural characteristics and molecular

  18. Settlement of marine periphytic algae in a tropical estuary

    Microsoft Academic Search

    S. Nayar; B. P. L. Goh; L. M. Chou

    2005-01-01

    This note describes settlement studies of marine periphytic algae on glass substrata in a tropical estuary in Singapore. The rates of production in terms of 14C radiotracer uptake, biomass in terms of chlorophyll a, community structure and cell abundance were measured from the settled periphytic algae at various depths in the water column and compared with the prevailing hydrographical conditions.

  19. Naphthenic acid biodegradation by the unicellular alga Dunaliella tertiolecta

    Microsoft Academic Search

    Dean M. Quesnel; Iyswarya M. Bhaskar; Lisa M. Gieg; Gordon Chua

    2011-01-01

    Naphthenic acids (NAs) are a major contributor to toxicity in tailings waste generated from bitumen production in the Athabasca Oil Sands region. While investigations have shown that bacteria can biodegrade NAs and reduce tailings toxicity, the potential of algae to biodegrade NAs and the biochemical mechanisms involved remain poorly understood. Here, we discovered that the marine alga Dunaliella tertiolecta is

  20. Algae culture for cattle feed and water purification. Final report

    Microsoft Academic Search

    F. T. Varani; S. Schellenbach; M. Veatch; P. Grover; J. Benemann

    1980-01-01

    The feasibility of algae growth on centrate from anaerobic digester effluent and the refeed of both effluent solids and the algae to feedlot cattle were investigated. The digester was operated with dirt feedlot manure. The study serves as a supplement for the work to design a utility sized digester for the City of Lamar to convert local feedlot manure into

  1. Oily Products from Mosses and Algae via Pyrolysis

    Microsoft Academic Search

    Ayhan Demirba?

    2006-01-01

    In this study, the fuel properties of mosses and algae, and the effect of pyrolysis temperature on the yield of bio-oil from moss and alga samples, were investigated. The yield of bio-oil from pyrolysis of the samples increased with temperature. The yields were increased up to 750 K in order to reach the plateau values at 775 K. The maximum

  2. Catalytic upgrading of biorefinery oil from micro-algae

    Microsoft Academic Search

    N. H. Tran; J. R. Bartlett; G. S. K. Kannangara; A. S. Milev; H. Volk; M. A. Wilson

    2010-01-01

    Micro-algae are seen as one of the major future fuel sources. Culture and growth of oil rich micro-algae and catalytic process for the conversion of their crude oils or biomass is reviewed here. While there is a significant literature on growth and extraction of oil from the resultant biomass the literature on the problems of refining these oils is diverse

  3. Practical Limitations Of Algae As A Sequestration Technique

    Microsoft Academic Search

    Edward A. Laws

    1991-01-01

    Large-scale cultivation of algae is being given serious consideration as a means of converting some of the CO2 emitted by stationary sources into organic matter which could be recycled as a biofuel. Such ideas are motivated by the observation that algae are the most efficient plants in converting solar energy into chemical energy via photosynthesis. An energetic analysis of algal

  4. Phenolic-based Adhesives of Marine Brown Algae

    Microsoft Academic Search

    Philippe Potin; Catherine Leblanc

    Brown algae, such as kelps and fucoids, occur over large areas of the subtidal and intertidal rocky shores, including tropical reef habitats, producing high biomass and determining the structure of the ecosystem (i.e. kelp forests). Brown algae live firmly attached to the substratum and are often exposed to high gradients of turbulence. Therefore, they experience drag and lift forces of

  5. LESSONS LEARNED ON ALGAE CONTROL STRATEGIES - NORTH AMERICAN SURVEY FINDINGS

    Microsoft Academic Search

    Erin Lyons; Sunil Kommineni; Bhavana Karnik; Malcolm Pirnie

    Algal growth within water treatment plants significantly impacts the finished water quality and treatment plant operations. Although extensive research exists on mitigating algae in source water, traditionally in-house experts and operators have relied on local knowledge and trial and error methodology for algae issues within treatment plants. As many utilities take a closer look at their treatment process for the

  6. Video micrography of algae photomovement and vectorial method of biomonitoring

    NASA Astrophysics Data System (ADS)

    Posudin, Yuri I.; Massjuk, N. P.; Lilitskaya, G. G.

    1996-01-01

    The simultaneous recording of several photomovement parameters of algae as test-functions during biomonitoring is proposed. Green alga Dunaliella viridis Teod. was used as the test- object for the estimation of different heavy metals. The quantitative changes of photomovement parameters as a criterion of toxicity were determined by means of the vectorial method of biomonitoring.

  7. AQU 04 Portable Algae Flow Cytometer Team Members

    E-print Network

    California at Los Angeles, University of

    for applications such as the on-field monitoring of the harmful algae bloom. It can also be used together and seagrasses. Further, many bloom-forming species are capable of toxin production which is harmful the harmful ones among algae communities. Also, the portable system can be used for constant vigilance

  8. Harmful Algal Blooms Algae are the most abundant photosynthetic

    E-print Network

    Harmful Algal Blooms The Issue Algae are the most abundant photosynthetic organisms in marine ecosystems and are essential components of marine food webs. Harmful algal bloom or "HAB" species are a small subset of algal species that negatively impact humans or the environment. Some harmful algae produce

  9. FAS6932: ALGAE BIOLOGY AND ECOLOGY Instructor: Professor Edward Phlips

    E-print Network

    Watson, Craig A.

    intertidal), their impacts (e.g. harmful algae blooms, food webs), and their applications (e.g. food.J. Gobler. 2012. The rise of harmful cyanobacteria blooms: The potential roles of eutrophication and climate change. Harmful Algae 14: 313-334. Szmant, A. 2002. Nutrient enrichment on coral reefs: Is it a major

  10. Update on Genomic Studies of Algae Paths toward Algal Genomics

    E-print Network

    Update on Genomic Studies of Algae Paths toward Algal Genomics Arthur R. Grossman* The Carnegie of genomic information that is being used to help researchers understand the gene content of organisms, how the expression of genes. In this introductory manuscript, I discuss select algae and how genomics is impacting

  11. Photoreversible Pigment: Occurrence in a Blue-Green Alga

    Microsoft Academic Search

    Joseph Scheibe

    1972-01-01

    A new photoreversible pigment has been isolated from the blue-green alga Tolypothrix tenuis. This pigment bears certain resemblances to phytochrome, except that absorption maxima for the two forms are in the green and red portions of the spectrum instead of the red and far-red. The pigment may control diverse differentiative processes in blue-green algae.

  12. ELECTRON MICROSCOPE STUDIES ON BLUE-GREEN ALGAE

    Microsoft Academic Search

    HANS RIS; R. N. SINGH

    1961-01-01

    Several species of blue-green algae were studied in thin sections with the electron microscope. Our electron micrographs confirm the view that the cell of blue-green algae is different and simpler in organization than the typical plant or animal cell. On the other hand, the general pattern of ultrastructure is the same as that found in bacteria and Streptomyces. The cell

  13. Blue-Green Algae and Freshwater Carbonate Deposits

    Microsoft Academic Search

    A. Pentecost

    1978-01-01

    Twenty-seven contemporary freshwater carbonate deposits were investigated (26 in the British Isles and 1 in S. Australia). The blue-green algae Schizothrix calcicola and Microcoleus vaginatus occurred at 23 of the sites. The remaining sites represented areas where deposition had ceased. About 1% of the dry mass of the deposits consisted of Cyanophyta. The assimilation rates of these algae, measured by

  14. Cell to substratum and cell to cell interactions of microalgae.

    PubMed

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems. PMID:24004676

  15. 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 ?-bands near 560 m?. At ?190° these bands split to give 4 peaks in the ?-region for b and c-type cytochromes, but no ?-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 m?. The action spectrum for the light reversal of CO-inhibited Vitreoscilla respiration shows maxima at 568, 534, and 416 m?. The results suggest that the terminal oxidase in these blue-greens is an o-type cytochrome. Images PMID:5932404

  16. Effects of nitrogen dioxide on algae

    SciTech Connect

    Wodzinski, R.S.; Alexander, M.

    1980-01-01

    Photosynthetic activity of Anabaena flos-aquae in a soil suspension at an initial pH of 4.9 was almost totally eliminated after 3 days of exposure to 5.0 ppM (..mu..l/liter) NO/sub 2/, at which time the pH had fallen to 3.9. In contrast, A. flos-aquae in soil suspensions at an initial pH of 6.0 was not inhibited after 3 days by 5.0 ppM NO/sub 2/, but the activity was reduced by half in the presence of 15.0 ppM NO/sub 2/; the pH was 6.5 and 5.8, respectively, in the NO/sub 2/-treated samples on day 3. Photosynthesis by the green algae Chlamydomonas reinhardtii and Ankistrodesmus falcatus in soil suspensions at an initial pH of approx. 4.2 was not appreciably affected by 15.0 ppM of NO/sub 2/ after 3 days, at which time the pH had fallen below 4.0. The high levels of NO/sub 2/ and low pH values required for toxicity suggest that blue-green and green algae probably will not be affected directly by NO/sub 2/ in polluted air.

  17. Effects of nitrogen dioxide on algae

    SciTech Connect

    Wodzinski, R.S.; Alexander, M.

    1980-01-01

    Photosynthetic activity of Anabaena flos-aquae in a soil suspension at an initial pH of 4.9 was almost totally eliminated after 3 days of exposure to 5.0 ppm (..mu..l/liter) NO/sub 2/, at which time the pH had fallen to 3.9. In contrast, A. flos-aquae in soil suspensions at an initial pH of 6.0 was not inhibited after 3 days by 5.0 ppm NO/sub 2/, but the activity was reduced by half in the presence of 15.0 ppm NO/sub 2/; the pH was 6.5 and 5.8, respectively, in the NO/sub 2/-treated samples on day 3. Photosynthesis by the green algae Chlamydomonas reinhardtii and Ankistrodesmus falcatus in soil suspensions at an initial pH of approx 4.2 was not appreciably affected by 15.0 ppm of NO/sub 2/ after 3 days, at which time the pH had fallen below 4.0. The high levels of NO/sub 2/ and low pH values required for toxicity suggest that blue-green and green algae probably will not be affected directly by NO/sub 2/ in polluted air.

  18. Algae 2011, 26(2): 181-192 DOI: 10.4490/algae.2011.26.2.181

    E-print Network

    Meyers, Steven D.

    of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can re; ballast water; dinoflagellate cysts; harmful algal blooms; microalgae; Tampa Bay INTRODUCTION In the pastAlgae 2011, 26(2): 181-192 DOI: 10.4490/algae.2011.26.2.181 Open Access Research Article Copyright

  19. Seasonal Occurrences of Epiphytic Algae on the Commercially Cultivated Red Alga Kappaphycus Alvarezii (Solieriaceae, Gigartinales, Rhodophyta)

    Microsoft Academic Search

    Charles S. Vairappan

    2006-01-01

    Common problems faced in farming of the red algal genus Kappaphycus\\/Eucheuma are “ice-ice disease” and the occurrence of epiphytes. Considerable work has been documented on “ice-ice disease” and it's mode of infection but limited information is available on the emergence of epiphytes. The present study addresses the phenomenon of epiphyte infection, its prevalence in commercially cultivated red alga, Kappaphycus alvarezii,

  20. Seasonal occurrences of epiphytic algae on the commercially cultivated red alga Kappaphycus alvarezii (Solieriaceae, Gigartinales, Rhodophyta)

    Microsoft Academic Search

    Charles S. Vairappan

    Common problems faced in farming of the red algal genus Kappaphycus\\/Eucheuma are “ice-ice disease” and the occurrence of epiphytes. Considerable work has been documented on “ice-ice disease” and it’s\\u000a mode of infection but limited information is available on the emergence of epiphytes. The present study addresses the phenomenon\\u000a of epiphyte infection, its prevalence in commercially cultivated red alga, Kappaphycus alvarezii,

  1. 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. PMID:25531025

  2. Plant & CellPhysiol. 14: 1081-1097 (1973) Photophosphorylation in intact algae: Effects of

    E-print Network

    Govindjee

    1973-01-01

    Plant & CellPhysiol. 14: 1081-1097 (1973) Photophosphorylation in intact algae: Effects alga Chlorella pyrenoidosa and of the blue-green alga Anacystis nidulans. A few measurements in extracts from intact cells of the green alga Chlorella in the early 1950's (3, 4), few workers measured

  3. THE POTENTIAL FOR MICRO-ALGAE AND OTHER "MICRO-CROPS" TO PRODUCE

    E-print Network

    Edwards, Paul N.

    THE POTENTIAL FOR MICRO-ALGAE AND OTHER "MICRO-CROPS" TO PRODUCE SUSTAINABLE BIOFUELS A REVIEW INTRODUCTION Biofuel derived from algae and other micro-crops has been proposed as an environmentally benign transportation fuel. Algae can be cultivated on low productivity lands using low quality water. Interest in algae

  4. Cultivation of algae with indigenous species – Potentials for regional biofuel production

    Microsoft Academic Search

    M. Odlare; E. Nehrenheim; E. Thorin; M. Gavare; M. Grube

    2011-01-01

    The massive need for sustainable energy has led to an increased interest in new energy resources, such as production of algae, for use as biofuel. There are advantages to using algae, for example, land use is much less than in terrestrial biofuel production, and several algae species can double their mass in 1day under optimized conditions. Most algae are phototrophs

  5. SEN 02 Portable Algae Flow Cytometer SEN 02.1 Overview

    E-print Network

    California at Los Angeles, University of

    properties, which is very useful for applications such as the on-field monitoring of the harmful algae bloom, especially to resolve the harmful ones among algae communities. Also, the portable system can be usedSEN 02 Portable Algae Flow Cytometer SEN 02.1 Overview The portable algae flow cytometer

  6. LIFETIME OF THE EXCITED STATE IN VIVO I. CHLOROPHYLL a IN ALGAE, AT ROOM

    E-print Network

    Govindjee

    cruentum, and the blue-green alga Anacystis nidulans was measured by the phase- shift method under in the red alga Porphyridium, and 1.2 ±0.4 nsec in the blue-green alga Anacystis. Dmitrievsky et al. (2LIFETIME OF THE EXCITED STATE IN VIVO I. CHLOROPHYLL a IN ALGAE, AT ROOM AND AT LIQUID NITROGEN

  7. Photophysiology and cellular composition of sea ice algae

    SciTech Connect

    Lizotte, M.P.

    1989-01-01

    The productivity of sea ice algae depends on their physiological capabilities and the environmental conditions within various microhabitats. Pack ice is the dominant form of sea ice, but the photosynthetic activity of associated algae has rarely been studied. Biomass and photosynthetic rates of ice algae of the Weddell-Scotia Sea were investigated during autumn and winter, the period when ice cover grows from its minimum to maximum. Biomass-specific photosynthetic rates typically ranged from 0.3 to 3.0 {mu}g C {center dot} {mu}g chl{sup {minus}1} {center dot} h{sup {minus}1} higher than land-fast ice algae but similar to Antarctic phytoplankton. Primary production in the pack ice during winter may be minor compared to annual phytoplankton production, but could represent a vital seasonal contribution to the Antarctic ecosystem. Nutrient supply may limit the productivity of ice algae. In McMurdo Sound, congelation ice algae appeared to be more nutrient deficient than underlying platelet ice algae based on: lower nitrogen:carbon, chlorophyll:carbon, and protein:carbohydrate; and {sup 14}C-photosynthate distribution to proteins and phospholipids was lower, while distribution to polysaccharides and neutral lipids was higher. Depletion of nitrate led to decreased nitrogen:carbon, chlorophyll:carbon, protein:carbohydrate, and {sup 14}C-photosynthate to proteins. Studied were conducted during the spring bloom; therefore, nutrient limitation may only apply to dense ice algal communities. Growth limiting conditions may be alleviated when algae are released into seawater during the seasonal recession of the ice cover. To continue growth, algae must adapt to the variable light field encountered in a mixed water column. Photoadaptation was studied in surface ice communities and in bottom ice communities.

  8. 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.

  9. Swimming like algae: biomimetic soft artificial cilia.

    PubMed

    Sareh, Sina; Rossiter, Jonathan; Conn, Andrew; Drescher, Knut; Goldstein, Raymond E

    2012-10-24

    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. PMID:23097503

  10. Granular activated algae for wastewater treatment.

    PubMed

    Tiron, O; Bumbac, C; Patroescu, I V; Badescu, V R; Postolache, C

    2015-01-01

    The study used activated algae granules for low-strength wastewater treatment in sequential batch mode. Each treatment cycle was conducted within 24 h in a bioreactor exposed to 235 ?mol/m(2)/s light intensity. Wastewater treatment was performed mostly in aerobic conditions, oxygen being provided by microalgae. High removal efficiency of chemical oxygen demand (COD) was achieved (86-98%) in the first hours of the reaction phase, during which the indicator's removal rate was 17.4 ± 3.9 mg O2/g h; NH4(+) was removed during organic matter degradation processes with a rate of 1.8 ± 0.6 mg/g h. After almost complete COD removal, the NH4(+) remaining in the liquor was removed through nitrification processes promoted by the increase of the liquor's oxygen saturation (O2%), the transformation rate of NH4(+) into NO3(-) increasing from 0.14 ± 0.05 to 1.5 ± 0.4 mg NH4(+)/g h, along with an O2% increase. A wide removal efficiency was achieved in the case of PO4(3-) (11-85%), with the indicator's removal rate being 1.3 ± 0.7 mg/g h. In the provided optimum conditions, the occurrence of the denitrifying activity was also noticed. A large pH variation was registered (5-8.5) during treatment cycles. The granular activated algae system proved to be a promising alternative for wastewater treatment as it also sustains cost-efficient microalgae harvesting, with microalgae recovery efficiency ranging between 99.85 and 99.99% after granules settling with a velocity of 19 ± 3.6 m/h. PMID:25812091

  11. [Sedimentation in the seasonal cycle of unicellular algae. Model analysis].

    PubMed

    Berdnikov, S V; Iadrovskaia, M V

    2001-01-01

    The efficiency of quick sedimentation (quicker then at normal condition) of unicellular algae at the end of seasonal cycle was studied in Okhotsk Sea. Model researches were based on the effect of competition of two algae populations. Analytical investigations of simplified variant of mathematical model and computing experiments showed that cell sedimentation and falling into the unfavorable (dark and cold) environment could be compensated by the increase in survival under these "negative" conditions. Vertical mixing of water has effect. Generally, mechanism of convective mixing is one of the factors that helps competing populations of unicellular algae to exist under conditions of changing environment. PMID:11544771

  12. Possibility of renewable energy production and CO 2 mitigation by thermochemical liquefaction of microalgae

    Microsoft Academic Search

    S Sawayama; T Minowa; S-Y Yokoyama

    1999-01-01

    The energy balance and CO2 mitigating effect of a liquid fuel production process from microalgae using thermochemical liquefaction were studied. Thermochemical liquefaction has the advantage of treating wet materials compared with direct combustion, gasification and pyrolysis, because it does not require a drying process. The yield of liquid fuel produced from Botryococcus braunii and its lower heating value were high

  13. Signal and Nutrient Exchange in the Interactions Between Soil Algae and Bacteria

    Microsoft Academic Search

    Max Teplitski; Sathish Rajamani

    \\u000a Microbial consortia of soil algae and prokaryotes have important functions in terrestrial ecosystems. Recent studies helped\\u000a delineate phylogenetic diversity of microbiota associated with soil algae. Some signals and nutrients exchanged between algae\\u000a and the associated bacteria were also identified. Both algae and bacteria appear to benefit from the interactions: algae derive\\u000a fixed nitrogen, vitamins, and hormones from their bacterial associates.

  14. Lytic characteristics and identification of two alga-lysing bacterial strains

    Microsoft Academic Search

    Haiyan Pei; Wenrong Hu

    2006-01-01

    All previously reported bacterial species which are capable of lysing harmful algae have been isolated from coastal environments\\u000a in which harmful algae blooms have occurred. Due to the low concentration of alga-lysing bacteria in an algal bloom, it is\\u000a difficult to isolate the alga-lysing bacteria by existing methods. In this paper, two algae-lysing bacterial strains, P01\\u000a and P03, have been

  15. A new compound, jolynamine, from marine brown alga Jolyna laminarioides.

    PubMed

    Khan, Abdul Majeed; Noreen, Sumaira; Imran, Zeba Parween; Choudhary, Muhammad Iqbal

    2011-05-01

    A new compound, jolynamine (1), was isolated from the marine brown alga Jolyna laminarioides collected from the coast of Karachi, Pakistan. In addition, four known compounds, namely saringosterol (2), loliolide (3), methyl-4-hydroxybenzoate (4) and propyl-4-hydroxybenzoate (5), were isolated for the first time from the marine brown alga Iyengaria stellata, and two known compounds, namely 3,4,5-trimethylaniline (6) and harmine (7), were isolated for the first time from the marine brown alga Melanothamnus afaqhusainii. Compound 6 is synthetically known but was isolated for the first time from a natural source. The structures of these compounds were elucidated with the help of powerful spectroscopic techniques. Furthermore, the methanolic extracts of both algae showed anti-microbial activities against various bacteria and fungi. PMID:21547840

  16. CHECKLIST AND BIBLIOGRAPHY OF THE MARINE BENTHIC ALGAE

    E-print Network

    Mcilwain, Jenny

    are technical/environmental reports, i.e., grey literature, which mention or list marine benthic algae in the Literature Cited section, 107 of the citations are published papers. One unpublished M.S. thesis (Potter

  17. 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)

  18. 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. PMID:24600873

  19. 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...

  20. Penicillinase (?-lactamase) formation by blue-green algae

    Microsoft Academic Search

    D. J. Kushner; Colette Breuil

    1977-01-01

    ß-Lactamase (penicillinase) activity was found in a number of strains of blue-green algae. In some cases, this enzyme permitted algae to overcome the inhibitory effects of penicillin. Production and localization of ß-lactamase were studied in a unicellular species, Coccochloris elabens (strain 7003), and in a filamentous, nitrogen-fixing Anabaena species (strain 7120). When cells were grown in a neutral medium with

  1. NADPH oxidases in Eukaryotes: red algae provide new hints!

    Microsoft Academic Search

    Cécile Hervé; Thierry Tonon; Jonas Collén; Erwan Corre; Catherine Boyen

    2006-01-01

    The red macro-alga Chondrus crispus is known to produce superoxide radicals in response to cell-free extracts of its green algal pathogenic endophyte Acrochaete operculata. So far, no enzymes involved in this metabolism have been isolated from red algae. We report here the isolation of a gene\\u000a encoding a homologue of the respiratory burst oxidase gp91phox in C. crispus, named Ccrboh.

  2. Effect of Epiphytic Algae on Photosynthetic Function of Potamogeton crispus

    Microsoft Academic Search

    Can Chen; Daqiang Yin; Bin Yu; Hankai Zhu

    2007-01-01

    The effect of blooming epiphytic algae on the leaf traits and photosynthetic function of the submersed macrophyte Potamogeton crispus was investigated under different epiphytic conditions and nutrition levels. Epiphytic algae growth was promoted at a rate of 0.16 chl a ?g.cm.d on leaf surface area under eutrophic conditions (N: 1 mg.L; P: 0.1 mg-L) and at a rate of 0.004

  3. Identification of cytokinin in a green algae extract

    NASA Astrophysics Data System (ADS)

    de-Lin, Duan; Feng, Pan; Li, Shuai; Jun-Shun, Zhang; Xin-Tong, Liu; Xiu-Geng, Fei

    1996-06-01

    Isopentenyladenosine (i6Ado) was identified, and trans-zeatin (trans-Z) and trans-zeatin riboside (trans-ZR) were detected by high pressure liquid chromatography (HPLC) but not verified with chromatography—mass spectrometry (GC-MS) analysis of cytokinin from the extracts of green algae ( Ulva pertusa (Kjellm), Enteromopha compressa and Monostroma sp.). This indicated that the green algae mixture contained cytokinin—like substances.

  4. Photobiological hydrogen production in green algae and photosynthetic bacteria

    Microsoft Academic Search

    Greenbaum

    1986-01-01

    We have shown that, under appropriate physiological conditions, certain freshwater and marine green algae are capable of splitting water to molecular hydrogen and oxygen in a sustained steady-state reaction. In these algae, the gaseous-fuel-producing reaction can be driven by light throughout the visible portion of the solar emission spectrum, including the long wavelength (red) 700-nm region. No external energy sources

  5. Algae biodiesel has potential despite inconclusive results to date

    Microsoft Academic Search

    Xiaowei Liu; Andres F. Clarens; Lisa M. Colosi

    A meta-analysis of several published life cycle assessments of algae-to-energy systems was developed to better understand the environmental implications of deploying this technology at large scales. Taken together, results from these six studies seemed largely inconclusive because of differences in modeling assumptions and system boundaries. To overcome this, the models were normalized using a generic pathway for cultivating algae in

  6. Photosynthetic H 2 metabolism in Chlamydomonas reinhardtii (unicellular green algae)

    Microsoft Academic Search

    Anastasios Melis

    2007-01-01

    Unicellular green algae have the ability to operate in two distinctly different environments (aerobic and anaerobic), and\\u000a 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

  7. Cultivation of the cryosestonic alga Koliella tatrae (Kol) Hind

    Microsoft Academic Search

    F. Hindák; J. Komárek

    1968-01-01

    The cryosestonic unicellular green algaKoliella tatrae\\u000a (Kol) Hind., which grows in the surface layers of the summer snow-fields of the Vel'ký Žl'ab valley in the Belánske Tatry Mountains (Czechoslovakia),\\u000a was started to be cultured at the laboratory. This alga may be considered as a typical (true) cryobiont, the optimal growth\\u000a of which requires about 4°C; long-lasting temperatures ranging from more

  8. Red algae as hosts for endophytic kelp gametophytes

    Microsoft Academic Search

    D. J. Garbary; K. Y. Kim; T. Klinger; D. Duggins

    1999-01-01

    We observed kelp gametophytes endophytic in the cell walls of 17 species of red algae from the San Juan Islands, Washington,\\u000a USA. Host algae were collected primarily from three sites dominated by different kelp assemblages, including (1) a subtidal\\u000a site dominated by Agarum fimbriatum Harvey, (2) a second subtidal site dominated by Nereocystis luetkeana (Mertens) Postels et Ruprecht, and (3)

  9. 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.

  10. Studies on nitrogen fixation by blue-green algae

    Microsoft Academic Search

    P. Fay; G. E. Fogg

    1962-01-01

    1.The unicellular blue-green alga Chlorogloea fritschii Mitra has been isolated in pure bacteria-free culture.2.Evidence showing that this alga is able to fix elementary nitrogen has been obtained by determinations by the micro-Kjeldahl method of increases in total combined nitrogen in culture and also by demonstration of the uptake of elementary nitrogen in a closed culture system by measurement of nitrogen\\/argon

  11. Nitrogen fixation by unicellular blue-green algae

    Microsoft Academic Search

    Rosmarie Rippka; Alasdair Neilson; Riyo Kunisawa; Germaine Cohen-Bazire

    1971-01-01

    The ability of some unicellular blue-green algae to grow at the expense of N2 under aerobic conditions has been confirmed and the distribution of this property in the Chroococcaceae has been investigated. It appears to be confined to strains with spherical cells enclosed by the multilaminate sheaths characteristic of the genus Gloeocapsa. Only two unicellular blue-green algae of this type

  12. Hydrocarbons in green and blue-green algae

    Microsoft Academic Search

    T. ?ezanka; J. Zahradník; M. Podojil

    1982-01-01

    Liquid column chromatography and thin-layer chromatography were used to determine the total content of hydrocarbons and gas\\u000a chromatography was used to evaluate composition of hydrocarbons in green algae (Chlorella kessleri, C. vulgaris, Chlorella sp.,Scenedesmus acutus, S. acuminatus, S. obliquus) and the blue-green alga (Spirulina platensis) cultivated under autotrophic or heterotrophic conditions. InC. kessleri cultivated under heterotrophic conditions the content of

  13. Ribonucleotide Reductase in Blue-Green Algae: Dependence on Adenosylcobalamin

    Microsoft Academic Search

    F. K. Gleason; J. M. Wood

    1976-01-01

    Ten species of freshwater blue-green algae exhibit an adenosylcobalamin-dependent ribonucleotide reductase, thus explaining the requirement for cobalt by these organisms. The evidence suggests a phylogenetic affinity between the cyanophytes and bacteria, such as Clostridium and Rhizobium, and the euglenoid flagellates, which also use the cofactor-dependent reductase. In contrast, the ribonucleotide reductase reaction in the few green algae surveyed shows no

  14. Algae That Cause Red Tide Found Off Maine Coast

    NSDL National Science Digital Library

    Misty Edgecomb

    This Bangor Daily News article provides general information about red tide in Maine and efforts being done to track the harmful algal bloom (HAB) events. There are four major red tide causing algae in Maine: Alexandrium, Dinophysis, Prorocentrum and Pseudonitzschia. These algae can cause serious health problems in humans and other marine animals. The &quot;first alert system&quot; now in place now monitors for sunlight and nutrient concentrations that may lead to red tide events.

  15. Viable Cyanobacteria and Green Algae from the Permafrost Darkness

    Microsoft Academic Search

    Tatiana A. Vishnivetskaya; Tatiana A

    2009-01-01

    This review represents an overview of the existence, distribution and abundance of the photoautotrophic microorganisms in\\u000a the deep subsurface permafrost of the Northeast Russia and McMurdo Dry Valleys, Antarctica. The morphology, growth rate, spectral\\u000a properties, phylogenetic position of the viable permafrost green algae and cyanobacteria have been studied. Viable photoautotrophs\\u000a were represented by unicellular green algae and filamentous cyanobacteria with

  16. 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.

  17. An overview of algae biofuel production and potential environmental impact.

    PubMed

    Menetrez, Marc Y

    2012-07-01

    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. PMID:22681590

  18. Algae 2013, 28(4): 297-305 http://dx.doi.org/10.4490/algae.2013.28.4.297

    E-print Network

    Jeong, Hae Jin

    planktonic food webs. Key Words: algicidal bacteria; feeding; food web; graze; harmful algal bloom; red tideAlgae 2013, 28(4): 297-305 http://dx.doi.org/10.4490/algae.2013.28.4.297 Open Access Review Copyright © The Korean Society of Phycology 297 http://e-algae.kr pISSN: 1226-2617 eISSN: 2093

  19. The potential for using cyanobacteria (blue-green algae) and algae in the biological control of plant pathogenic bacteria and fungi

    Microsoft Academic Search

    Martin M. Kulik

    1995-01-01

    Cyanobacteria (blue-green algae) and eukaryote algae occur in freshwater, marine, and terrestrial (soil) habitats. In fact, these microorganisms comprise most of the world's biomass. Although the cyanobacteria are mostly photoautotrophic, some are facultative heterotrophs, capable of growing on certain substrates in darkness. Also, some are non-phototrophic and hence, are obligate heterotrophs. A number of cyanobacteria and eukaryote algae, particularly macroalgae,

  20. AlgaGEM – a genome-scale metabolic reconstruction of algae based on the Chlamydomonas reinhardtii genome

    PubMed Central

    2011-01-01

    Background Microalgae have the potential to deliver biofuels without the associated competition for land resources. In order to realise the rates and titres necessary for commercial production, however, system-level metabolic engineering will be required. Genome scale metabolic reconstructions have revolutionized microbial metabolic engineering and are used routinely for in silico analysis and design. While genome scale metabolic reconstructions have been developed for many prokaryotes and model eukaryotes, the application to less well characterized eukaryotes such as algae is challenging not at least due to a lack of compartmentalization data. Results We have developed a genome-scale metabolic network model (named AlgaGEM) covering the metabolism for a compartmentalized algae cell based on the Chlamydomonas reinhardtii genome. AlgaGEM is a comprehensive literature-based genome scale metabolic reconstruction that accounts for the functions of 866 unique ORFs, 1862 metabolites, 2249 gene-enzyme-reaction-association entries, and 1725 unique reactions. The reconstruction was compartmentalized into the cytoplasm, mitochondrion, plastid and microbody using available data for algae complemented with compartmentalisation data for Arabidopsis thaliana. AlgaGEM describes a functional primary metabolism of Chlamydomonas and significantly predicts distinct algal behaviours such as the catabolism or secretion rather than recycling of phosphoglycolate in photorespiration. AlgaGEM was validated through the simulation of growth and algae metabolic functions inferred from literature. Using efficient resource utilisation as the optimality criterion, AlgaGEM predicted observed metabolic effects under autotrophic, heterotrophic and mixotrophic conditions. AlgaGEM predicts increased hydrogen production when cyclic electron flow is disrupted as seen in a high producing mutant derived from mutational studies. The model also predicted the physiological pathway for H2 production and identified new targets to further improve H2 yield. Conclusions AlgaGEM is a viable and comprehensive framework for in silico functional analysis and can be used to derive new, non-trivial hypotheses for exploring this metabolically versatile organism. Flux balance analysis can be used to identify bottlenecks and new targets to metabolically engineer microalgae for production of biofuels. PMID:22369158

  1. 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).

  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. PMID:21495012

  3. 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.

  4. News about cryptochrome photoreceptors in algae.

    PubMed

    Beel, Benedikt; Müller, Nico; Kottke, Tilman; Mittag, Maria

    2013-02-01

    Cryptochromes (CRYs) are flavoproteins that are known as blue light photoreceptors in many organisms. Recently, genome sequences from a variety of algae became available. Functional characterizations of animal-like CRYs from Oestreococcus tauri, Chlamydomonas reinhardtii and Phaeodactylum tricornutum highlighted novel functions and properties. As arising from studies in fungi, certain algal CRYs of the "cryptochrome photolyase family" (PtCPF1, OtCPF1) have dual or even triple functions. They are involved in blue light perception and/or in the circadian clock and are able to repair DNA damages. On the other hand, the animal-like aCRY from C. reinhardtii is not only acting as sensory blue light- but also as sensory red light receptor thus expanding our current view of flavoproteins in general and CRYs in particular. The observed broad spectral response points to the neutral radical state of flavin, which is assumed to be the dark form in aCRY in contrast to the plant CRYs. PMID:23154511

  5. Mixotrophy in red tide algae raphidophytes.

    PubMed

    Jeong, Hae Jin

    2011-01-01

    Marine raphidophytes are common red tide organisms that are distributed worldwide. They are known to be harmful to other plankton and fish and have often caused large-scale fish mortality in many countries. Thus, the population dynamics of raphidophytes is a critical concern for scientists, the aquaculture industry, and government officers from many countries. Raphidophyte growth and mortality should be investigated to understand bloom dynamics. Raphidophytes were thought to be exclusively autotrophic organisms. However, several recent studies have revealed that raphidophytes are able to feed on heterotrophic and autotrophic bacteria, i.e. raphidophytes are mixotrophic algae. Further, high-resolution video microscopy has revealed the mechanism by which raphidophytes feed on bacteria, which involves capturing prey cells in the mucus excreted by mucocysts and engulfing the cells through mucocysts. These discoveries may influence the conventional view on both raphidophyte bloom dynamics and plankton energy flow and carbon cycling. In the present study, I review prey, feeding mechanisms, and ingestion rates of mixotrophic marine raphidophytes. In addition, I examine the ecological significance of raphidophyte mixotrophy. PMID:21518079

  6. [The effects of blue algae on health].

    PubMed

    van Riel, A J H P; Schets, F M; Meulenbelt, J

    2007-08-01

    Cyanobacteria (blue algae) regularly cause recreational waters to become murky and smelly. Skin irritation and mild gastrointestinal disorders have regularly been reported following recreational activities in water suspected of being contaminated with cyanobacteria. The exact cause of these effects on health is not clear. Severe effects are not to be expected from recreational exposure to water contaminated with cyanobacteria. Cyanobacteria can produce hepatotoxins, neurotoxins, cytotoxins and irritants. In Brazil lethal intoxications have occurred due to the occurrence of toxins in drinking water and in dialysis fluid. The Dutch policy is based on the Commissie Integraal Waterbeheer (Commission Integral Water Management) guidelines for recreational waters. It is not clear to what extent the other cyanotoxins occur in the Netherlands. However, several genera ofcyanobacteria capable of producing these other cyanotoxins have been found in the Netherlands. For a good risk assessment in the Netherlands, more information is needed on the effects on health of cyanobacteria. There is also a need for more data on the prevalence of different cyanobacteria and toxins in Dutch recreational waters. PMID:17784694

  7. Characterization of Tertiary Catalan lacustrine oil shales: Discovery of extremely organic sulphur-rich Type I kerogens

    NASA Astrophysics Data System (ADS)

    Sinninghe Damsté, Jaap S.; de las Heras, F. Xavier C.; van Bergen, Pim F.; de Leeuw, Jan W.

    1993-01-01

    The kerogens of three Tertiary Catalan lacustrine oil shales were analyzed by light microscopy, flash pyrolysis-gas chromatography-mass spectrometry, and bulk composition methods (elemental analysis, Rock Eval pyrolysis). Two of the three kerogens (Ribesalbes and Campins) are extremely rich in organic sulphur (atomic S org/C ratio > 0.04) and hydrogen (atomic ratio H/C ratio > 1.5) and are, consequently, classified as Type I-S kerogens. Very characteristic distribution patterns of flash pyrolysis products (e.g., alkan-9- and -10-ones, alkadienes) of the Ribesalbes kerogen revealed that it is predominantly composed of fossilized organic matter of the freshwater alga Botryococcus braunii. These two findings demonstrate that sulphurization of organic matter may also occur in lacustrine sediments provided that sulphate is supplied by external sources. Data on the third kerogen sample (Cerdanya) suggest that the freshwater alga Pediastrum may contain a (partly) aromatic biomacromolecule that is selectively preserved upon diagenesis. These findings testify to the large variability in palaeodepositional conditions in lacustrine environments. A comparison of the biomarker composition of the extract of the Ribesalbes oil shale with the kerogen composition indicate that biomarkers often cannot be used to assess the major sources of organic matter in such settings. A similar conclusion can be drawn from a comparison of literature data concerning the Messel Oil Shale.

  8. The Tropical Brown Alga Lobophora variegata (Lamouroux) Womersley: A Prospective Bioindicator for Ag Contamination in Tropical Coastal Waters

    E-print Network

    Paris-Sud XI, Université de

    The Tropical Brown Alga Lobophora variegata (Lamouroux) Womersley: A Prospective Bioindicator determined in the brown alga Lobophora variegata, using radiotracer techniques. Results indicate that this widely distributed alga could be a useful bioindicator species for surveying silver contamination

  9. Anti-phytopathogenic activities of macro-algae extracts.

    PubMed

    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

  10. 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. PMID:21174128

  11. 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. PMID:20933402

  12. 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

  13. Influence of algae on photolysis rates of chemicals in water

    SciTech Connect

    Zepp, R.G.; Schlotzhauer, P.F.

    1983-08-01

    Sunlight-induced algal transformations of 22 nonionic organic chemicals were studied in order to provide kinetic results and equations concerning the influence of algae on the behavior of pollutants in freshwater environments. Screening studies indicated that green and blue-green algae, at concentrations of 1-10 mg of chlorophyll a/L, accelerate photoreaction of certain polycylic aromatic hydrocarbons, organophosphorus compounds, and anilines in water. The rate of change in aniline concentration, (P), in the aniline-Chlamydomonas photoreaction can be described by the following expression: rate = A(1 + B/(P))-1. At low substrate concentrations, the reaction rate is first order with respect to both algae and substrate concentration. Methyl parathion and parathion photoreacted 390 times more rapidly when sorbed by algae than in distilled water, and aniline and m-toluidine reacted over 12000 times faster, indicating that light-induced algal transformations of certain pollutants may be significant. Other results indicated that reaction rates are unaffected by heat-killing the algae. 27 references

  14. Synergistic cooperation between wastewater-born algae and activated sludge for wastewater treatment: influence of algae and sludge inoculation ratios.

    PubMed

    Su, Yanyan; Mennerich, Artur; Urban, Brigitte

    2012-02-01

    An algal-bacterial culture, composed of wastewater-born algae and activated sludge, was cultivated to treat domestic wastewater and accumulate biomass simultaneously. The influence of algae and sludge inoculation ratios on the treatment efficiency and the settleability of the accumulated biomass were investigated. There was no significant effect of the inoculation ratios on the chemical oxygen demand removal. Comparatively, the nutrients removal and related mechanism were varied with different inoculation ratios. The highest nitrogen and phosphorus removal efficiencies were observed with 5:1 (algae/sludge) culture (91.0±7.0% and 93.5±2.5%, respectively) within 10 days, which was 5-40% higher and 2-4 days faster than those with other inoculation ratios. The biomass settleability was improved with the assistance of sludge, and the 1:5 (algae/sludge) culture showed the best settleability. Furthermore, 16S rDNA gene analysis showed that the bacterial communities were varying with different algae and sludge inoculation ratios and some specific bacteria were enriched during operation. PMID:22189078

  15. 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. PMID:24632439

  16. 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

  17. Importance of algae as a potential source of biofuel.

    PubMed

    Singh, A K; Singh, M P

    2014-01-01

    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. PMID:25535720

  18. Stable chloroplast transformation of the unicellular red alga Porphyridium species.

    PubMed

    Lapidot, Miri; Raveh, Dina; Sivan, Alex; Arad, Shoshana Malis; Shapira, Michal

    2002-05-01

    Red algae are extremely attractive for biotechnology because they synthesize accessory photosynthetic pigments (phycobilins and carotenoids), unsaturated fatty acids, and unique cell wall sulfated polysaccharides. We report a high-efficiency chloroplast transformation system for the unicellular red microalga Porphyridium sp. This is the first genetic transformation system for Rhodophytes and is based on use of a mutant form of the gene encoding acetohydroxyacid synthase [AHAS(W492S)] as a dominant selectable marker. AHAS is the target enzyme of the herbicide sulfometuron methyl, which effectively inhibits growth of bacteria, fungi, plants, and algae. Biolistic transformation of synchronized Porphyridium sp. cells with the mutant AHAS(W492S) gene that confers herbicide resistance gave a high frequency of sulfomethuron methyl-resistant colonies. The mutant AHAS gene integrated into the chloroplast genome by homologous recombination. This system paves the way for expression of foreign genes in red algae and has important biotechnological implications. PMID:12011332

  19. 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.

  20. Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production

    E-print Network

    Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production Transportation Energy The Issue Algae biofuels directly address the Energy Commission's Public Interest Energy Research fuels more carbonintensive than conventional biofuels. Critics of this study argue that alternative

  1. Hydrodynamic Synchronization and Metachronal Waves on the Surface of the Colonial Alga Volvox carteri

    E-print Network

    Goldstein, Raymond E.

    Hydrodynamic Synchronization and Metachronal Waves on the Surface of the Colonial Alga Volvox of the colonial alga Volvox carteri, whose large size and ease of visualization make it an ideal model organism

  2. One-Two-Three Punch Clobbers Toxic Algae, Restores Fremont Lake

    E-print Network

    Nebraska-Lincoln, University of

    One-Two-Three Punch Clobbers Toxic Algae, Restores Fremont Lake Final Report Fremont Lake #20 Water-two-three punch to knockout toxic algae and restore water quality in Nebraska's numerous sandpit lakes. "It seems

  3. Author's personal copy A novel ocean color index to detect oating algae in the global oceans

    E-print Network

    Meyers, Steven D.

    (Kahru et al., 2007), diatoms (Sathyendranath et al., 2004), harmful algae (Cannizzaro et al., 2008 been used to monitor and study harmful algal blooms (HAAuthor's personal copy A novel ocean color index to detect oating algae in the global oceans

  4. Aragonitic Pennsylvanian phylloid algae from New Mexico: The missing link

    SciTech Connect

    Kirkland, B.L.; Moore, C.H. Jr. (Louisiana State Univ., Baton Rouge (United States)); Dickson, J.A.D. (Univ. of Cambridge (United Kingdom))

    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.

  5. 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. PMID:23391579

  6. Combining micro-structures and micro-algae to increase lipid production for bio-fuel

    Microsoft Academic Search

    Saurabh Vyawahare; Emilly Zhu; Troy Mestler; André. Estévez-Torres; Robert Austin

    2011-01-01

    3rd generation bio-fuels like lipid producing micro-algae are a promising source of energy that could replace our dependence on petroleum. However, until there are improvements in algae oil yields, and a reduction in the energy needed for processing, algae bio-fuels are not economically competitive with petroleum. Here, we describe our work combining micro-fabricated devices with micro-algae Neochloris oleoabundans, a species

  7. Origin of land plants: Do conjugating green algae hold the key?

    Microsoft Academic Search

    Sabina Wodniok; Henner Brinkmann; Gernot Glöckner; Andrew J Heidel; Hervé Philippe; Michael Melkonian; Burkhard Becker

    2011-01-01

    Background  The terrestrial habitat was colonized by the ancestors of modern land plants about 500 to 470 million years ago. Today it\\u000a is widely accepted that land plants (embryophytes) evolved from streptophyte algae, also referred to as charophycean algae.\\u000a The streptophyte algae are a paraphyletic group of green algae, ranging from unicellular flagellates to morphologically complex\\u000a forms such as the stoneworts

  8. A bangiophyte red alga from the Proterozoic of arctic Canada.

    PubMed

    Butterfield, N J; Knoll, A H; Swett, K

    1990-10-01

    Silicified peritidal carbonate rocks of the 1250- to 750-million-year-old Hunting Formation, Somerset Island, arctic Canada, contain fossils of well-preserved bangiophyte red algae. Morphological details, especially the presence of multiseriate filaments composed of radially arranged wedge-shaped cells derived by longitudinal divisions from disc-shaped cells in uniseriate filaments, indicate that the fossils are related to extant species in the genus Bangia. Such taxonomic resolution distinguishes these fossils from other pre-Ediacaran eukaryotes and contributes to growing evidence that multicellular algae diversified well before the Ediacaran radiation of large animals. PMID:11538072

  9. Homogeneity of Danish Environmental and Clinical Isolates of Shewanella algae

    PubMed Central

    Vogel, Birte Fonnesbech; Holt, Hanne Marie; Gerner-Smidt, Peter; Bundvad, Anemone; Søgaard, Per; Gram, Lone

    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. PMID:10618264

  10. Phylogeny and Nucleomorph Karyotype Diversity of Chlorarachniophyte Algae TIA D. SILVER,a,1

    E-print Network

    Archibald, John

    Phylogeny and Nucleomorph Karyotype Diversity of Chlorarachniophyte Algae TIA D. SILVER,a,1 SAYAKA/or reticulopod-forming marine algae with chlorophyll a- and b-containing plastids of secondary endosymbiotic. THE chlorarachniophytes are an enigmatic group of unicellular marine algae with diverse morphologies and a widespread

  11. FL47CH15-Goldstein ARI 25 November 2014 9:45 Green Algae as Model

    E-print Network

    Goldstein, Raymond E.

    FL47CH15-Goldstein ARI 25 November 2014 9:45 Green Algae as Model Organisms for Biological Fluid green algae, spanning from the unicellular Chlamydomonas to multicellular Volvox, have emerged as model of flagellar synchronization. Green algae are well suited to the study of such problems because of their range

  12. Climate implications of algae-based bioenergy systems Andres Clarens, PhD

    E-print Network

    Walter, M.Todd

    Climate implications of algae-based bioenergy systems Andres Clarens, PhD Assistant Professor Civil of algae and other nonconventional feedstocks, are being developed. This talk will explore several systems priorities. This is an especially challenging problem for algae-based biofuels because production pathways

  13. PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1

    E-print Network

    Martone, Patrick T.

    PHYSIOLOGICAL PERFORMANCE OF INTERTIDAL CORALLINE ALGAE DURING A SIMULATED TIDAL CYCLE1 Rebecca J, Lobban and Harrison 1997, Helmuth and Hofmann 2001). During high tide, intertidal algae are underwater algae may be emerged and exposed to increased light stress, elevated air tem- peratures, and increased

  14. Ghana: Western Ghana's Fisherfolk Starve Amid Algae Infestation BY JESSICA MCDIARMID, 18 APRIL 2012

    E-print Network

    Belogay, Eugene A.

    Ghana: Western Ghana's Fisherfolk Starve Amid Algae Infestation BY JESSICA MCDIARMID, 18 APRIL 2012 not to continue fishing." Sargassum is the algae after which the Sargasso Sea - an elongated region in the middle down while tonnes of the algae were removed. In some areas people were warned not to swim due

  15. DESICCATION PROTECTION AND DISRUPTION: A TRADE-OFF FOR AN INTERTIDAL MARINE ALGA1

    E-print Network

    Denny, Mark

    DESICCATION PROTECTION AND DISRUPTION: A TRADE-OFF FOR AN INTERTIDAL MARINE ALGA1 Luke J. H. Hunt2, California 93950, USA For marine algae, the benefits of drying out are often overshadowed by the stresses of desiccation in the intertidal turf alga Endocladia muricata (Endlichter) J. Agardh. Laboratory experiments

  16. Red Algae Respond to Waves: Morphological and Mechanical Variation in Mastocarpus papillatus Along

    E-print Network

    Denny, Mark

    Red Algae Respond to Waves: Morphological and Mechanical Variation in Mastocarpus papillatus Along Grove, California, 93950 Abstract. Intertidal algae are exposed to the potentially severe drag forces generated by crashing waves, and several species of brown algae respond, in part, by varying the strength

  17. Hydrogen isotope fractionation in freshwater and marine algae: II. Temperature and nitrogen limited growth rate effects

    E-print Network

    Sachs, Julian P.

    Hydrogen isotope fractionation in freshwater and marine algae: II. Temperature and nitrogen limited isotope fractionation in freshwater algae: I. Variations among lipids and spe- cies. Organic Geochemistry. Two species of freshwater green algae, Eudorina unicocca and Volvox aureus, were grown in batch

  18. Photosynthetic and growth responses of three freshwater algae to phosphorus limitation and daylength

    E-print Network

    Bossard, Peter

    Photosynthetic and growth responses of three freshwater algae to phosphorus limitation., green alga Sphaerocystis schroeteri and cyanobacterium Phormidium luridum, were grown under contrasting of the green alga S. schroeteri decreased the most (ca. sixfold) under P limitation compared with the other two

  19. Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background Behavior

    E-print Network

    ARTICLE Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background performed using Stokes Raman scattering for compositional analysis of algae. Two algal species, Chlorella while acquiring Raman signals from the algae. The time dependence of fluorescence background is char

  20. ACARYOCHLORIS EXPLAINING THE RIDDLE OF CHLOROPHYLL D IN RED ALGAE AND EXPANDING PAR FOR OXYGENIC PHOTOSYNTHESIS

    E-print Network

    Oregon, University of

    ACARYOCHLORIS ­ EXPLAINING THE RIDDLE OF CHLOROPHYLL D IN RED ALGAE AND EXPANDING PAR FOR OXYGENIC strain is shown to live epi- phytically on the red alga Gelidium caulacantheum, which itself is harvested by the red alga. Availability of far red light, however, is relatively unaffected by DOM or red

  1. Early Cretaceous benthic associations (foraminifera and calcareous algae) of a shallow tropical-water platform

    E-print Network

    Husinec, Antun

    Early Cretaceous benthic associations (foraminifera and calcareous algae) of a shallow tropical of benthic foraminifera and calcareous algae in order to establish a precise, combined benthic biozonation species of calcareous algae, distributed among 11 genera, were recovered from the Lower Cretaceous shallow

  2. Energy From Algae Using Microbial Fuel Cells Sharon B. Velasquez-Orta,1

    E-print Network

    ARTICLE Energy From Algae Using Microbial Fuel Cells Sharon B. Velasquez-Orta,1 Tom P. Curtis,1 with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable

  3. INTRODUCTION Cryptomonad algae are postulated to be a chimaera of two

    E-print Network

    McFadden, Geoff

    INTRODUCTION Cryptomonad algae are postulated to be a chimaera of two different eukaryotic cells incorporating cryptomonad endosymbiont gene sequences ally them loosely with red algae (Douglas et al., 1991a that the endosymbiont was an early evolutionary intermediate that pre-dates the red algae (Cavalier-Smith, 1992

  4. HoustonChronicle.com -Tiny honor a big deal for algae scientist HoustonChronicle.

    E-print Network

    Jeong, Hae Jin

    HoustonChronicle.com - Tiny honor a big deal for algae scientist HoustonChronicle. com Section-mail this story June 18, 2005, 5:48PM Tiny honor a big deal for algae scientist By DAVID A. FAHRENTHOLD Washington Post Sometimes, algae can be the highest form of flattery. ADVERTISEMENTSo it was for Diane K. Stoecker

  5. Xylochloris irregularis gen. et sp. nov. (Trebouxiophyceae, Chlorophyta), a novel subaerial coccoid green alga

    E-print Network

    green alga JIR I´ NEUSTUPA 1 *, MAREK ELIA´ S1 , PAVEL SKALOUD 1 , YVONNE NE MCOVA´ 1 AND LENKA irregularis gen. et sp. nov. (Trebouxiophyceae, Chlorophyta), a novel subaerial coccoid green alga. Phycologia 50: 57­66. DOI: 10.2216/08-64.1 The phylogenetic diversity of subaerial coccoid green algae remains

  6. Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness, and Strength

    E-print Network

    Buehler, Markus J.

    Hierarchical Silica Nanostructures Inspired by Diatom Algae Yield Superior Deformability, Toughness algae that is mainly composed of amorphous silica, which features a hierarchical structure that ranges in diatom algae as a basis to study a bioinspired nanoporous material implemented in crystalline silica. We

  7. Investigation of Flow Characteristics in an Airlift-Driven Raceway Reactor for Algae Cultivation

    E-print Network

    Investigation of Flow Characteristics in an Airlift-Driven Raceway Reactor for Algae Cultivation are the most common choice for outdoor algae cultivation due to their low cost relative to enclosed. Algae require adequate mixing in order to maximize exposure to essential nutrients for growth

  8. Toward Systems Biology in Brown Algae to Explore Acclimation and Adaptation to the Shore Environment

    E-print Network

    Paris-Sud XI, Université de

    Toward Systems Biology in Brown Algae to Explore Acclimation and Adaptation to the Shore,2 Catherine Boyen,1,2 and Anne Siegel4,5 Abstract Brown algae belong to a phylogenetic lineage distantly siliculosus as a model organism for brown algae has represented a framework in which several omics techniques

  9. A Framework to Report the Production of Renewable Diesel from Algae

    E-print Network

    A Framework to Report the Production of Renewable Diesel from Algae Colin M. Beal & Colin H. Smith(s) 2010. This article is published with open access at Springerlink.com Abstract Recently, algae have algae are a viable source for renewable diesel, three questions that must be answered are (1) how much

  10. PHYLOGENETIC DIVERSITY OF TRENTEPOHLIALEAN ALGAE ASSOCIATED WITH LICHEN-FORMING FUNGI1

    E-print Network

    PHYLOGENETIC DIVERSITY OF TRENTEPOHLIALEAN ALGAE ASSOCIATED WITH LICHEN-FORMING FUNGI1 Matthew P 60605-2496, USA Nearly one-fourth of the lichen-forming fungi asso- ciate with trentepohlialean algae algae has provided a phy- logenetic context within which questions regarding the lichenization

  11. The Seattle Times: Nation & World: Algae gives professor a taste of immortality Home delivery

    E-print Network

    Jeong, Hae Jin

    The Seattle Times: Nation & World: Algae gives professor a taste of immortality Home delivery, 2005 - Page updated at 12:00 AM Algae gives professor a taste of immortality By David A. Fahrenthold The Washington Post E-mail article Print view Search Most e-mailed Most read RSS Sometimes, algae can

  12. Optical microplates for high-throughput screening of photosynthesis in lipid-producing algae{,

    E-print Network

    Basu, Amar S.

    Optical microplates for high-throughput screening of photosynthesis in lipid- producing algae-producing algae of interest in 2nd generation biofuels. By conducting 96 experiments in parallel, photoirradiance the study of photosynthesis in algae. Societal challenges in energy sustainability have renewed interest

  13. Algae as a sustainable energy source for biofuel production in Iran: A case study

    Microsoft Academic Search

    Gholamhassan Najafi; Barat Ghobadian; Talal F. Yusaf

    2011-01-01

    Algae can be converted directly into energy, such as biodiesel, bioethanol and biomethanol and therefore can be a source of renewable energy. There is a growing interest for biodiesel production from algae because of its higher yield non-edible oil production and its fast growth that does not compete for land with food production. About 50% of algae weight is oil

  14. Photocatalytic Inhibition of Algae Growth Using TiO2, WO3, and

    E-print Network

    Ouellette, Anthony J. A.

    drag and additional fuel consumption. Excessive algae build-up can occlude drainage pipes and foulPhotocatalytic Inhibition of Algae Growth Using TiO2, WO3, and Cocatalyst Modifications C L O V I as photocatalytic surfacing agents to inhibit the attachment and growth of Oedogonium, a sessile, filamentous algae

  15. Importance of algae in the diet of the oligochaetes Lumbriculus variegatus (MÜller) and Rhyacodrilus sodalis (Eisen)

    Microsoft Academic Search

    James W. Moore

    1978-01-01

    The importance of algae in the diet of the oligochaetes Lumbriculus variegatus and Rhyacodrilus sodalis was determined from cellections made in a eutrophic bay from April 1977 to April 1978. During the summer, algae represented 70–85% of the gut contents of both species. The most frequently ingested algae were Cymatopleura elliptica, Cymbella spp., Epithemia turgida, Pinnularia spp., and Synedra ulna.

  16. Hâ metabolism in photosynthetic organisms. I. Dark Hâ evolution and uptake by algae and mosses

    Microsoft Academic Search

    A. Ben-Amotz; D. L. Erbes; M. A. Riederer-Henderson; D. G. Peavey; M. Gibbs

    1975-01-01

    Dark Hâ metabolism was studied in marine and fresh water red algae, the green alga, Chlamydomonas, and mosses. A time variable and temperature-sensitive anaerobic incubation was required prior to Hâ evolution. Hâ evolution was sensitive to disalicylidenepropanediamine. An immediate Hâ uptake was observed in these algae. Immediate dark Hâ uptake but no evolution was observed in the mosses. A cell-free

  17. CLOSING THE CARBON LOOP: GROWING ALGAE USING SUSTAINABLE CO2 FROM BIO-WASTE

    EPA Science Inventory

    Record oil prices, poor air quality, and the threat of global warming have resulted in renewed interest in micro algae for its great potential as a biofuels feedstock. However, research is predominantly focused on growing algae with coal flue gas, and extracting the algae oils...

  18. GENOMIC DNA ISOLATION FROM GREEN AND BROWN ALGAE (CAULERPALES AND FUCALES) FOR MICROSATELLITE LIBRARY CONSTRUCTION1

    E-print Network

    Teixeira, Sara

    NOTE GENOMIC DNA ISOLATION FROM GREEN AND BROWN ALGAE (CAULERPALES AND FUCALES) FOR MICROSATELLITE A method for isolating high-quality DNA is pre- sented for the green algae Caulerpa sp. (C. racemosa, C. prolifera, and C. taxifolia) and the brown alga Sargassum muticum. These are introduced, and in- vasive

  19. Crystalline Glycoprotein Cell Walls of Algae: Their Stucture, Composition and Assembly

    Microsoft Academic Search

    K. Roberts

    1974-01-01

    Cell walls from various algae within the Chlamydomonaceae display, when negatively stained and examined in the electron microscope, a crystalline lattice component. On the basis of the Fourier transforms of micrographs of the cell wall, the algae have been classified into five classes. Most of the algae examined fall into class II. The two-dimensional repeating morphological unit cell of the

  20. Facts about Cyanobacteria (Blue-green Algae) and Cyanobacterial Harmful Algal Blooms

    E-print Network

    ) and Cyanobacterial Harmful Algal Blooms (CyanoHABs) Cyanobacteria (blue-green algae) Cyanobacteria are bacteria smell bad. #12;2 Cyanobacterial harmful algal blooms (CyanoHABs) CyanoHABs are algae blooms and how they form Cyanobacterial blooms occur when algae that are normally present grow exuberantly

  1. YSI Blue-Green Algae (BGA) Sensors Spatial Water Quality Mapping of the Potomac River Estuary

    E-print Network

    Boynton, Walter R.

    YSI Blue-Green Algae (BGA) Sensors Spatial Water Quality Mapping of the Potomac River Estuary Visit integrated Yellow Spring Instruments (YSI) blue- green algae (BGA) sensors into our system to evaluate of blue-green algae ·Observed phycocyanin containing organisms were mainly colony forming (e

  2. HOLARCTIC ECOLOGY 4: 201-207. Copenhagen 1981 Microcommunities of algae on a Sphagnum mat

    E-print Network

    Notre Dame, University of

    (1973) and concerns nitrogen- fixing algae. Generally, where blue-green, heterocyst- ous epiphytesHOLARCTIC ECOLOGY 4: 201-207. Copenhagen 1981 Microcommunities of algae on a Sphagnum mat Celia A. Hooper Hooper, C, A, 1981, Microcommunities of algae on a Sphagnum mat, - Holarct, Ecol, 4: 201

  3. 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 ...

  4. Automated object recognition of blue-green algae for measuring water quality—A preliminary study

    Microsoft Academic Search

    Stefan U. Thiel; Ron J. Wiltshire; Lance J. Davies

    1995-01-01

    In this paper a computer algorithm for the automated detection of blue-green algae is presented. Samples of seven species of blue-green algae and two species of green algae were examined under a microscope and transferred to a computer. The microscope pictures were stored as digital images. In order to locate the organisms Image Segmentation routines were applied. Image Enhancement improved

  5. Integrating filamentous ‘green tide’ algae into tropical pond-based aquaculture

    Microsoft Academic Search

    Pedro H. de Paula Silva; Shannon McBride; Rocky de Nys; Nicholas A. Paul

    2008-01-01

    ‘Green tide’ algae bloom in eutrophic environments with fast growth rates and efficient nutrient uptake. These same characteristics are sought after for algae in integrated aquaculture systems. We examined the effect of two key variables, salinity and total ammonia nitrogen (TAN), on the growth of three filamentous ‘green tide’ algae, Cladophora coelothrix, Chaetomorpha indica and Ulva sp. Survival and growth

  6. Toxic Effect of Certain Metals Mixture on Some Physiological and Morphological Characteristics of Freshwater Algae

    Microsoft Academic Search

    Salwa A. Shehata; Mohamed R. Lasheen; Gamila H. Ali; Imam A. Kobbia

    1999-01-01

    The toxic effect of multi metals mixture which exist simultaneously in aquatic ecosystem on natural phytoplankton assemblages (green algae, blue-green algae and diatoms) was studied. For this purpose a laboratory scale unit was designed to evaluate the effect of continuous flow metals mixture in forms if triple and penta metals in Nile water algae. Clear changes in algal biomass in

  7. Effect of decomposing filamentous algae on the growth of Elodea canadensis Michx. (a laboratory experiment)

    Microsoft Academic Search

    Ewa Pieczy?ska; Agata Tarmanowska

    1996-01-01

    Elodea canadensis Michx. was cultivated in the laboratory in the presence and absence of decomposing filamentous algae (Cladophora glomerata (L.) Kütz.) at the stage of about 50% loss of their initial weight. The presence of decomposing algae resulted in a visible increase of nutrient concentration in the water. The effect of decomposing algae on macrophyte growth depends on the proportion

  8. Biomacromolecules of algae and plants and their fossil analogues

    Microsoft Academic Search

    Jan W. de Leeuw; Gerard J. M. Versteegh; Pim F. van Bergen

    A review of our current understanding of resistant biomacromolecules derived from present and past algae and higher plants is presented. Insight in the nature of recent and fossil macromolecules is strongly hampered by the difficulties in obtaining the material in pure and unaltered form. For the extant material, avoiding artificial condensation and structural alteration as a result of chemical isolation

  9. Are the green algae (phylum Viridiplantae) two billion years old?

    Microsoft Academic Search

    Bernard TEYSSÈDRE

    2006-01-01

    In his book, Life on a young planet, A.H. KNOLL states that the first documented fossils of green algae date back 750 Ma. However, according to B. TEYSSÈDRE's book, La vie invisible, they are much older. Using a method which combines paleontology and molecular phylogeny, this paper is an inquiry into the Precambrian fossils of some \\

  10. Chile, 2009 HYDRAULIC MANAGEMENT OF FILAMENTOUS ALGAE IN

    E-print Network

    Paris-Sud XI, Université de

    7 th ISE & 8 th HIC Chile, 2009 HYDRAULIC MANAGEMENT OF FILAMENTOUS ALGAE IN OPEN-CHANNEL NETWORKS channels which are specific eco-systems for many reasons. Firstly, they have to fulfill hydraulic, artificial channels have a relatively simple geometry and their hydraulic variables are easier to monitor

  11. Settlement of marine periphytic algae in a tropical estuary

    NASA Astrophysics Data System (ADS)

    Nayar, S.; Goh, B. P. L.; Chou, L. M.

    2005-08-01

    This note describes settlement studies of marine periphytic algae on glass substrata in a tropical estuary in Singapore. The rates of production in terms of 14C radiotracer uptake, biomass in terms of chlorophyll a, community structure and cell abundance were measured from the settled periphytic algae at various depths in the water column and compared with the prevailing hydrographical conditions. Relatively higher periphytic algal settlement was observed at 1 m depth, even though it was not statistically different from other depths. Diatoms such as Skeletonema costatum and Thalassiosira rotula dominated the assemblage, together with the marine cyanobacteria Synechococcus sp. The three settlement parameters viz., periphytic algal production, chlorophyll a and cell counts showed significant differences between the days of settlement, with no significant differences observed for different depths. The periphytic algal community in this study comprised 30 microalgal species, dominated by diatoms (78%), followed by cyanobacteria (19% - primarily Synechococcus sp.), green flagellates (1%), dinoflagellates (1%) and other forms accounting for the remaining 1% of the total cell counts. Correlation studies and principal component analysis (PCA) revealed significant influence of silicate concentrations in the water column with the settlement of periphytic algae in this estuary. Though photoinhibited at the surface, photosynthetically available radiation did not seem to influence the overall settlement of periphytic algae. Diatoms and Synechococcus in the periphytic algal community were influenced by water temperature, PAR, pH and dissolved oxygen as seen in the PCA plots.

  12. An Effect of Antibiotics produced by Plankton Algae

    Microsoft Academic Search

    E. Steemann Nielsen

    1955-01-01

    THE clear blue oceanic water in the tropics and subtropics, where the standing crops both of phyto-plankton and zooplankton are extremely low-the reason why the water is so clear and blue-should on this account show very low organic productivity by the plankton algae. Measurements with the carbon-14 method have shown this to be true1.

  13. Biosorption of reactive dyes on the green alga Chlorella vulgaris

    Microsoft Academic Search

    Zümriye Aksu; Sevilay Tezer

    2005-01-01

    Biosorption of three vinyl sulphone type reactive dyes (Remazol Black B (RB), Remazol Red RR (RR) and Remazol Golden Yellow RNL (RGY)) onto dried Chlorella vulgaris, a green alga was investigated in a batch system. The algal biomass exhibited the highest dye uptake capacity at the initial pH value of 2.0 for all dyes. The effect of temperature on equilibrium

  14. Biochemical and Pathogenic Properties of Shewanella alga and Shewanella putrefaciens

    Microsoft Academic Search

    SHIDEH KHASHE; J. MICHAEL JANDA

    1998-01-01

    We characterized 49 strains of Shewanella spp. from clinical (n 5 31) and nonhuman (n 5 18) sources. Most Shewanella alga organisms (Gilardi biovar 2; Centers for Disease Control and Prevention (CDC) biotype 2) originated from clinical material (92%), failed to produce acid from carbohydrates other than D-ribose, and were biochemically and enzymatically fairly homogeneous. In contrast, Shewanella putrefaciens organisms

  15. NADPH oxidases in Eukaryotes: red algae provide new hints!

    PubMed

    Hervé, Cécile; Tonon, Thierry; Collén, Jonas; Corre, Erwan; Boyen, Catherine

    2006-03-01

    The red macro-alga Chondrus crispus is known to produce superoxide radicals in response to cell-free extracts of its green algal pathogenic endophyte Acrochaete operculata. So far, no enzymes involved in this metabolism have been isolated from red algae. We report here the isolation of a gene encoding a homologue of the respiratory burst oxidase gp91(phox) in C. crispus, named Ccrboh. This single copy gene encodes a polypeptide of 825 amino acids. Search performed in available genome and EST algal databases identified sequences showing common features of NADPH oxidases in other algae such as the red unicellular Cyanidioschyzon merolae, the economically valuable red macro-alga Porphyra yezoensis and the two diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana. Domain organization and phylogenetic relationships with plant, animal, fungal and algal NADPH oxidase homologues were analyzed. Transcription analysis of the C. crispus gene revealed that it was over-transcribed during infection of C. crispus gametophyte by the endophyte A. operculata, and after incubation in presence of atrazine, methyl jasmonate and hydroxyperoxides derived from C20 polyunsaturated fatty acids (PUFAs). These results also illustrate the interest of exploring the red algal lineage for gaining insight into the deep evolution of NADPH oxidases in Eukaryotes. PMID:16344959

  16. BACTERIA, FUNGI, AND UNICELLULAR ALGAE Blank page retained for pagination

    E-print Network

    CHAPTER VI BACTERIA, FUNGI, AND UNICELLULAR ALGAE #12;Blank page retained for pagination #12;MARINE BACTERIA AND FUNGI IN THE GULF OF MEXICO I By CLAUDE E. ZOBELL, Scripps lrutitution of Oceano; Bavendamm 1932), there are very few published reports on bacteria and fungi in the nearby Gulf of Mexico

  17. 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

  18. 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. PMID:24369344

  19. 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

  20. Application of spaceborne SAR imagery in monitoring green algae

    Microsoft Academic Search

    Yuan Xinzhe; Liu Jianqiang; Xie Chunhua; Zeng Tao; Song Xingai

    2009-01-01

    Synthetic Aperture Radar (SAR) satellite image is first used to monitor dramatically growing green algae near Qingdao coastal in 2008. The system played important role in ensuring Qingdao 2008 Olympic Sailing Competition. Based on imagery statistic analysis, the influences of radar parameter on detection performance are evaluated. A processing method which used in practice is presented. Processing results consist with

  1. ROCK FILTERS FOR REMOVAL OF ALGAE FROM LAGOON EFFLUENTS

    EPA Science Inventory

    The objective of this project was to show that rock filtration was an effective, low cost unit process for removing algae from lagoon effluents and correspondingly upgrading lagoon treatment. Sedimentation is the primary mechanism of algal removal within rock filter. The settling...

  2. TOXICITY AND UPTAKE OF KEPONE IN MARINE UNICELLULAR ALGAE

    EPA Science Inventory

    Four species of marine unicellular algae were exposed to Kepone in laboratory bioassays. EC50 values after seven days' growth, in micrograms/liter (ppm), were--Chlorococcum sp., 0.35; Dunaliella tertiolecta, 0.58; Nitzschia sp., 0.60; Thalassiosira pseudonana, 0.60. When exposed ...

  3. Biodiesel Fuel Production from Algae as Renewable Energy

    Microsoft Academic Search

    Sharif Hossain; Aishah Salleh

    Biodiesel is biodegradable, less CO2 and NOx emissions. Continuous use of petroleum sourced fuels is now widely recognized as unsustainable because of depleting supplies and the contribution of these fuels to the accumulation of carbon dioxide in the environment. Renewable, carbon neutral, transport fuels are necessary for environmental and economic sustainability. Algae have emerged as one of the most promising

  4. Algae biodiesel has potential despite inconclusive results to date.

    PubMed

    Liu, Xiaowei; Clarens, Andres F; Colosi, Lisa M

    2012-01-01

    A meta-analysis of several published life cycle assessments of algae-to-energy systems was developed to better understand the environmental implications of deploying this technology at large scales. Taken together, results from these six studies seemed largely inconclusive because of differences in modeling assumptions and system boundaries. To overcome this, the models were normalized using a generic pathway for cultivating algae in open ponds, converting it into biodiesel, and processing the nonlipid fraction using anaerobic digestion. Meta-analysis results suggest that algae-based biodiesel would result in energy consumption and greenhouse gas emissions on par with terrestrial alternatives such as corn ethanol and soy biodiesel. Net energy ratio and normalized greenhouse gas emissions were 1.4 MJ produced/MJ consumed and 0.19 kg CO(2)-equivalent/km traveled, respectively. A scenario analysis underscores the extent to which breakthroughs in key technologies are needed before algae-derived fuels become an attractive alternative to conventional biofuels. PMID:22104101

  5. Ocean Planet: There Are Algae in Your House!

    NSDL National Science Digital Library

    As part of this activity, students look in their own homes for foods that contain ingredients derived from seaweed . The activity points out that seaweeds are not really weeds but large forms of marine algae, and that seaweed derivatives are used in a large variety of foods and household products. Objectives, a list of materials, instructions, and a take-home worksheet are included.

  6. Soil and Plant Responses to Lipid-Extracted Algae 

    E-print Network

    Lewis, Katie

    2014-08-25

    -C was mineralized and lost as CO2 compared with 15% of added wheat straw-C. Lipid-extracted algae enhanced aggregate formation and soil SOC storage in microaggregates at 0-15 cm depth over a 12-month field incubation with greater mean weight diameter by 12 months...

  7. 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.

  8. Unusual mitosis in the red alga Porphyridium purpureum

    Microsoft Academic Search

    R. Bronchart; V. Demoulin

    1977-01-01

    Porphyridium purpureum (Bory) Drew et Ross (Syn.: P. cruentum Nägeli) is a classical laboratory organism and one of the few red algae easily grown in large quantities. This would make it an obvious candidate for investigation of red algal mitosis with the electron microscope. The nuclei are, however, quite small and fast dividing, so that previous attempts remained apparently unsuccessful1,2

  9. Photosynthetic hydrogen and oxygen production by green algae

    Microsoft Academic Search

    E. Greenbaum; J. W. Lee

    1997-01-01

    An overview of photosynthetic hydrogen and oxygen production by green algae in the context of its potential as a renewable chemical feed stock and energy carrier is presented. Beginning with its discovery by Gaffron and Rubin in 1942, motivated by curiosity-driven laboratory research, studies were initiated in the early 1970s that focused on photosynthetic hydrogen production from an applied perspective.

  10. Bioactive phloroglucinols from the brown alga Zonaria diesingiana

    Microsoft Academic Search

    Puntip Wisespongpand; Masayuki Kuniyoshi

    2003-01-01

    Three phloroglucinols with a C-20 acyl side chain were isolated from marine brown alga Zonaria diesingiana. The structures were determined on the basis of NMR spectral analyses and comparison with data in the literature. They all showed antibacterial activity against Bacillus subtilis and Staphylococcus aureus and cytotoxic activity by inhibiting cell division in fertilized sea urchin eggs (Echinometra mathaei). These

  11. Growth and longevity in the crustose red alga Petrocelis middendorffii

    Microsoft Academic Search

    R. T. Paine; C. J. Slocum; D. O. Duggins

    1979-01-01

    Petrocelis middendorffii is a non-calcareous encrusting red alga growing on rocks in the middle and upper intertidal zone. We have photographically followed the fate of 43 individual plants for periods up to 88 months at Waadah Island, near Neah Bay, Washington (USA). Growth is slow, with surface area increasing about 4% year-1 for those individuals growing. Other plants were observed

  12. Interactions between algae and the microbial loop in experimental microcosms

    Microsoft Academic Search

    Florence D. Hulot; Peter J. Morin; Michel Loreau

    2001-01-01

    We conducted a short-term microcosm experiment to study the direct and indirect effects of a bacterivore on bacteria and the dynamics of two species of green algae. We introduced Scenedesmus, Chlorella and Colpidium, a bacterivorous ciliate, succes- sively in a carbon-rich medium. Bacteria were introduced with Scenedesmus, Chlorella and Colpidium. The experiment lasted 40 days, preventing us from detecting whether

  13. A review of heavy metal adsorption by marine algae

    NASA Astrophysics Data System (ADS)

    Jin-Fen, Pan; Rong-Gen, Lin; Li, Ma

    2000-09-01

    Accumulation of heavy metals by algae had been studied extensively for biomonitoring or bioremediation purposes. Having the advantages of low cost raw material, big adsorbing capacity, no secondary pollution, etc., algae may be used to treat industrial water containing heavy metals. The adsorption processes were carried out in two steps: rapid physical adsorption first, and then slow chemical adsorption. pH is the major factor influencing the adsorption. The Freundlich equation fitted very well the adsorption isotherms. The uptake decreased with increasing ionic strength. The principal mechanism of metallic cation sequestration involves the formation of complexes between a metal ion and functional groups on the surface or inside the porous structure of the biological material. The carboxyl groups of alginate play a major role in the complexation. Different species of algae and the algae of the same species may have different adsorption capacity. Their selection affinity for heavy metals was the major criterion for the screening of a biologic adsorbent to be used in water treatment. The surface complex formation model (SCFM) can solve the equilibrium and kinetic problems in the biosorption.

  14. Intracellular invasion of green algae in a salamander host

    PubMed Central

    Kerney, Ryan; Kim, Eunsoo; Hangarter, Roger P.; Heiss, Aaron A.; Bishop, Cory D.; Hall, Brian K.

    2011-01-01

    The association between embryos of the spotted salamander (Ambystoma maculatum) and green algae (“Oophila amblystomatis” Lamber ex Printz) has been considered an ectosymbiotic mutualism. We show here, however, that this symbiosis is more intimate than previously reported. A combination of imaging and algal 18S rDNA amplification reveals algal invasion of embryonic salamander tissues and cells during development. Algal cells are detectable from embryonic and larval Stages 26–44 through chlorophyll autofluorescence and algal 18S rDNA amplification. Algal cell ultrastructure indicates both degradation and putative encystment during the process of tissue and cellular invasion. Fewer algal cells were detected in later-stage larvae through FISH, suggesting that the decline in autofluorescent cells is primarily due to algal cell death within the host. However, early embryonic egg capsules also contained encysted algal cells on the inner capsule wall, and algal 18S rDNA was amplified from adult reproductive tracts, consistent with oviductal transmission of algae from one salamander generation to the next. The invasion of algae into salamander host tissues and cells represents a unique association between a vertebrate and a eukaryotic alga, with implications for research into cell–cell recognition, possible exchange of metabolites or DNA, and potential congruence between host and symbiont population structures. PMID:21464324

  15. Controlled artificial upwelling in a fjord to combat toxic algae

    NASA Astrophysics Data System (ADS)

    McClimans, T. A.; Hansen, A. H.; Fredheim, A.; Lien, E.; Reitan, K. I.

    2003-04-01

    During the summer, primary production in the surface layers of some fjords depletes the nutrients to the degree that some arts of toxic algae dominate the flora. We describe an experiment employing a bubble curtain to lift significant amounts of nutrient-rich seawater to the light zone and provide an environment in which useful algae can survive. The motivation for the experiment is to provide a local region in which mussels can be cleansed from the effects of toxic algae. Three 100-m long, perforated pipes were suspended at 40 m depth in the Arnafjord, a side arm of the Sognefjord. Large amounts of compressed air were supplied during a period of three weeks. The deeper water mixed with the surface water and flowed from the mixing region at 5 to 15 m depth. Within a few days, the mixture of nutrient-rich water covered most of the inner portion of Arnafjord. Within 10 days, the plankton samples showed that the artificial upwelling produced the desired type of algae and excluded the toxic blooms that were occurring outside the manipulated fjord arm. The project (DETOX) is supported by the Norwegian ministries of Fisheries, Agriculture and Public Administration.

  16. Carotenoid Biosynthesis in the Primitive Red Alga Cyanidioschyzon merolae

    Microsoft Academic Search

    Francis X. Cunningham; Hansel Lee; Elisabeth Gantt

    2007-01-01

    Cyanidioschyzon merolae is considered to be one of the most primitive of eukaryotic photosynthetic organisms. To obtain insights into the origin and evolution of the pathway of carotenoid biosynthesis in eukaryotic plants, the carotenoid content of C. merolae was ascertained, genes encoding enzymes of carotenoid biosynthesis in this unicellular red alga were identified, and the activities of two candidate pathway

  17. CHEMICAL COMPOSITION OF THE WALLS OF CERTAIN ALGAE

    Microsoft Academic Search

    MARY E. WURDACK

    In spite of the fact that numerous investigations of the nature of cell walls of algae have been made, the recorded data are still far too incomplete to be of the greatest service to science. It is usually impossible to obtain from the literature a complete record of the composition of the walls of the most commonly occurring fresh water

  18. INFLUENCE OF ALGAE ON PHOTOLYSIS RATES OF CHEMICALS IN WATER

    EPA Science Inventory

    Sunlight-induced algal transformations of 22 nonionic organic chemicals were studied in order to provide kinetic results and equations concerning the influence of algae on the behavior of pollutants in freshwater environments. Screening studies indicated that green and blue-green...

  19. Photometrical analysis with photosensory domains of photoreceptors in green algae

    Microsoft Academic Search

    Takatoshi Kagawa; Noriyuki Suetsugu

    2007-01-01

    Chloroplast photoorientation in the green alga Mougeotia scalaris is controlled by blue and red light. The properties of the LOV domains of phototropin A and B were consistent with previous data of action spectra and photoreceptor lifetime for blue light-mediated photoorientation. The LOV domains of the neochromes did not bind flavin, while the domains of neochrome 2 contributed to multimer

  20. Using CO2 & Algae to Treat Wastewater and

    E-print Network

    Keller, Arturo A.

    Using CO2 & Algae to Treat Wastewater and Produce Biofuel Feedstock Tryg Lundquist Cal Poly State School, UCSB March 23, 2007 #12;CO2 and Wastewater Treatment · WW Treatment Technologies · Scale Actinastrum sp. #12;Major Wastewater Treatment Technologies in U.S. Activated Sludge 6,800 Facilities 25

  1. Niche of harmful alga Aureococcus anophagefferens revealed through ecogenomics

    Microsoft Academic Search

    Christopher Gobler; Dianna Berry; Sonya Dyhrman; Steven Wilhelm; A. Salamov; A. V. Lobanov; Y. Zhang; J. L. Collier; L. L. Wurch; A. B. Kustka; B. D. Dill; M. Shah; N. C. Verberkmoes; A. Kuo; A. Terry; J. Pangilinan; E. A. Lindquist; S. Lucas; I. T. Paulsen; T. K. Hattenrath-Lehmann; S. C. Talmage; E. A. Walker; F. Koch; A. M. Burson; M. A. Marcoval; Y.-Z. Tang; G. R. Lecleir; K. J. Coyne; G. M. Berg; E. M. Bertrand; M. A. Saito; V. N. Gladyshev; I. V. Grigoriev

    2011-01-01

    Harmful algal blooms (HABs) cause significant economic and ecological damage worldwide. Despite considerable efforts, a comprehensive understanding of the factors that promote these blooms has been lacking, because the biochemical pathways that facilitate their dominance relative to other phytoplankton within specific environments have not been identified. Here, biogeochemical measurements showed that the harmful alga Aureococcus anophagefferens outcompeted co-occurring phytoplankton in

  2. Research on the life cycles of harmful algae: A commentary

    Microsoft Academic Search

    Karen A. Steidinger

    2010-01-01

    The knowledge of the life cycles of harmful algae has advanced substantially in the last decade, in part through increased support of major research programs such as the SEED and the ECOHAB – Gulf of Maine projects. As with most research, the new knowledge answers some questions but raises more that require further inquiry, particularly since life-cycle strategies appear to

  3. Spatial Interaction Filters for Monitoring Harmful Algae Blooms

    Microsoft Academic Search

    Yang Cai; Sai Ho Chung; Richard Stumpf; Timothy Wynne; Michelle Tomlinson

    In this paper, the authors use Spatial Interaction Filters (SIF) to simulate human experts' visual process in tracking spatial interactive objects. The algorithm includes spatial density based pixel clustering and object interaction descriptions, such as Contact Area Index (CAI) and correlation filter. The algorithm is designed to automatically track the Harmful Algae Bloom (HAB) targets. In the case studies, SIF

  4. Marine blue-green algae have a unique osmoregulatory system

    Microsoft Academic Search

    M. A. Mackay; R. S. Norton; L. J. Borowitzka

    1983-01-01

    Currently, blue-green algae are classified as either freshwater or marine depending on the ionic requirements of the strain, not on the type of habitat from which the strain was isolated. As a result many strains isolated from saline environments are classified as freshwater strains. New parameters were sought which might correlate better the physiology of marine strains with their habitat.

  5. Mucilage secretion and the movements of blue-green algae

    Microsoft Academic Search

    A. E. Walsby

    1968-01-01

    Summary Recent discoveries of ultrastructures which might be involved in the gliding movements of blue-green algae have been reviewed, and in the light of these discoveries the role of mucilage secretion in movement has been reconsidered. The formation and behaviour of mucilage rings in filaments ofAnabaena cylindrica is described. The behaviour of the mucilage rings indicates that each cell has

  6. Gas Vacuole Development in a Blue-Green Alga

    Microsoft Academic Search

    J. Robert Waaland; Daniel Branton

    1969-01-01

    De novo production of gas vacuoles can be induced in the blue-green alga Nostoc muscorum by transferring the cells from a defined medium to distilled water. The unusual ultrastructure of the gas vacuole membranes permits their easy recognition when specimens are prepared for electron microscopy by freeze-etching. The youngest gas vacuoles are biconical organelles; 48 hours after induction the gas

  7. Bioactive natural products from blue-green algae

    Microsoft Academic Search

    Gregory M. L. Patterson; Linda K. Larsen; Richard E. Moore

    1994-01-01

    Since 1981 we have cultured and prepared lipophilic and hydrophilic extracts from more than 1500 strains representing some 400 species of blue-green algae. Screening for a wide variety of potentially useful bioactivities, including cytotoxic, multi-drug-resistance reversal, antifungal, and antiviral effects, has led to the discovery and identification of numerous novel bioactive metabolites including peptides, macrolides and glycosides.

  8. Toxins of a Blue-Green Alga: Similarity to Saxitoxin

    Microsoft Academic Search

    Eugene Jackim; John Gentile

    1968-01-01

    Toxins were isolated from the freshwater blue-green alga Aphanizomenon flos-aquae. The toxic fractions were characterized by paper and thin-layer chromatography, isolation characteristics, infrared spectra, physiological activity, and reactivity with specific color reagents. The toxic fractions appear to be similar, if not identical, to saxitoxin (paralytic shellfish toxin), which is produced by the marine dinoflagellate Gonyaulax catenella.

  9. Spectral shifting by dyes to enhance algae growth

    SciTech Connect

    Prokop, A.; Ahmed, S.A.; Fekri, M.; Murad, M.; Quinn, M.F.

    1984-11-01

    The photosynthetic growth action spectrum of a green alga at three bands of visible light (blue, orange, and red) at fixed quanta input and under light-limiting conditions was measured in a batch cultivation system. Quantum efficiencies (biomass dry weight increment per quanta absorbed) were better in the yellow-red region than in the blue region. Results served as a basis for the design and optimization of a dye system that would shift the energy of solar radiation to the required wavelength range by absorbing ultraviolet to blue radiation and emitting in the yellow-red, thus enhancing algae growth. Direct incorporation of dyes into the growth medium, although theoretically expected to enhance growth, in fact resulted in dye decomposition, toxicity to algae and consequently in growth inhibition. Indirect application of dyes in a double tubular reactor (algae inside and dye solution outside) demonstrated growth enhancement for certain dyes with high quantum yields and stability, which had suitable absorption/emission spectra for artificial light sources used. The maximum indirect growth enhancement was obtained using rhodamine 6G at a concentration of 3 X 10/sup -5/M with tungsten filament lamp sources.

  10. Life Strategies of Filamentous Algae in the Northern Baltic Proper

    Microsoft Academic Search

    Mikko Kiirikki; Annamaija Lehvo

    1997-01-01

    Short lived filamentous algae are a major component of the rocky-shore macroalgal vegetation of eutrophic waters in the Baltic Sea. They show considerable variation in abundance both seasonally and from year to year. In this study the seasonal pattern of growth and reproduction is documented in six species to outline their life strategies. Five of the species studied were reproductive

  11. Bactericidal activity of phlorotannins from the brown alga Ecklonia kurome

    Microsoft Academic Search

    Koki Nagayama; Yoshitoshi Iwamura; Toshiyuki Shibata; Izumi Hirayama; Takashi Nakamura

    2002-01-01

    The bactericidal activity of phlorotannins from brown algae against food-borne pathogenic bacteria (25 strains), methicillin-resistant Staphylococcus aureus (MRSA) (nine strains) and Streptococcus pyogenes (one strain) was examined and compared with that of catechins. In addition, the effect of the oral administration of phlorotannins on mice was investigated. Phloro- tannins, which are oligomers of phloroglucinol, were extracted from thalli of the

  12. Spatozoate and varninasterol from the brown alga Spatoglossum variabile

    Microsoft Academic Search

    Atta-ur-Rahman; M. Iqbal Choudhary; Safdar Hayat; A. Majeed Khan; Aftab Ahmad; Shahid Malik

    1999-01-01

    Two new compounds, spatozoate and varninasterol were isolated from Spatoglossum variabile. Four known compounds, fucosterol, cholesta-5-ene-23-yne-3?-ol, apiole and nothoapiole were also isolated for the first time from the methanolic extracts of this alga. The structure elucidation of the new compounds were carried out with the help of modern spectroscopic techniques.

  13. Higher plant origins and the phylogeny of green algae.

    PubMed

    Devereux, R; Loeblich, A R; Fox, G E

    1990-07-01

    5S rRNA sequences from six additional green algae lend strong molecular support for the major outlines of higher plant and green algae phylogeny that have been proposed under varying naming conventions by several authors. In particular, the molecular evidence now available unequivocally supports the existence of at least two well-separated divisions of the Chlorobionta: the Chlorophyta and the Streptophyta (i.e., charophytes) (according to the nomenclature of Bremer). The chlamydomonad 5S rRNAs are, however, sufficiently distinct from both clusters that it may ultimately prove preferable to establish a third taxon for them. In support of these conclusions 5S rRNA sequence data now exist for members of four diverse classes of chlorophytes. These sequences all exhibit considerably more phylogenetic affinity to one another than any of them show toward members of the other cluster, the Streptophyta, or the two Chlamydomonas strains. Among the Charophyceae, new 5S rRNA sequences are provided herein for three genera, Spirogyra, Klebsormidium, and Coleochaete. All of these sequences and the previously published Nitella sequence show greater resemblance among themselves and to the higher plants than they do to any of the other green algae examined to date. These results demonstrate that an appropriately named taxon that includes these green algae and the higher plants is strongly justified. The 5S rRNA data lack the resolution needed, however, to unequivocally determine which of several subdivisions of the charophytes is the sister group of the land plants. The evolutionary diversity of Chlamydomonas relative to the other green algae was recognized in earlier 5S rRNA studies but was unanticipated by ultrastructural work.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2116527

  14. Recovery of dilute metal ions by biosorption on river algae and its component

    SciTech Connect

    Fujita, Toyohisa; Kogita, Hiroki; Mamiya, Mitsuo [Akita Univ. (Japan). Mining Coll.; Yen, W.T. [Queen`s Univ., Kingston, Ontario (Canada)

    1995-12-31

    Green algae taken from an acidic mine drainage and blue-green algae take from an alkaline hot spring stream were collected and tested for their ability to recover or remove dilute metal ions. Experimental results demonstrated that unwashed blue-green algae and washed green algae effectively adsorbed base metals ions and eluted the at pH 1. It was also found that washed and dried algae adsorbed precious metal ions more effectively than unwashed algae. For example, the washed and dried blue-green algae was capable of adsorbing 0.31 kg of gold pre kg of algae. The gold from tetrachloroaurate solution which was adsorbed on washed blue-green algae was found to change to a metallic state following initial metal binding. In the case of a dilute gold complex solution leached with thiourea, only a small amount of gold could be captured by algae. Further experiments were conducted on components of the algae, such as alginic acid, agar, cellulose and chitin and mixtures of these components, in order to determine their contribution to metal adsorption characteristics. However, a mixture of these two components demonstrated both good adsorption and desorption characteristics indicating an interaction between the individual components.

  15. Modeling and control of algae detachment in regulated canal networks Ophelie Fovet, Xavier Litrico and Gilles Belaud

    E-print Network

    Paris-Sud XI, Université de

    Modeling and control of algae detachment in regulated canal networks Ophelie Fovet, Xavier Litrico and Gilles Belaud Abstract-- Algae development in open-channel networks in- duce major disturbances because these algae developments consists in flushing the fixed algae. The flush is carried out by increasing

  16. Carnets de Gologie / Notebooks on Geology -Article 2006/03 (CG2006_A03) Are the green algae (phylum Viridiplantae)

    E-print Network

    Paris-Sud XI, Université de

    Carnets de Géologie / Notebooks on Geology - Article 2006/03 (CG2006_A03) 1 Are the green algae planet, A.H. KNOLL states that the first documented fossils of green algae date back 750 Ma. However" and of a primitive clade of green algae, the Pyramimonadales. A paraphyletic group of unicellular green algae, named

  17. Project EARTH-11-RR2: Co-evolution of iodine antioxidant mechanism in marine algae and Earth-surface

    E-print Network

    Henderson, Gideon

    Project EARTH-11-RR2: Co-evolution of iodine antioxidant mechanism in marine algae and Earth algae (yet they are lacking in green algae) ­ but the phylogenetic distribution of iodine accumulation haloperoxidases. The first appearance and important divergence of brown algae occurred within the last 200 myr

  18. Chemical characterization of torbanites by transmission micro-FTIR spectroscopy: Origin and extent of compositional heterogeneities

    NASA Astrophysics Data System (ADS)

    Landais, Patrick; Rochdi, Aïcha; Largeau, Claude; Derenne, Sylvie

    1993-06-01

    Four Permian to Carboniferous torbanites of various geographical origins were examined by transmission micro-FTIR spectroscopy on doubly polished thin sections (10-25 ?m). Several types of heterogeneities (different types of organic matrix; yellow and orange Botryococcus braunii colonies) were identified and chemically characterized. Important differences were noted between the organic constituents of the matrix and the algal bodies, regarding the intensity of OH, C?O, and aromatic C?C absorptions. The previous IR studies of torbanites on bulk samples therefore afforded substantially biased information on the composition of B. braunii fossil colonies, on their oil potential, and on the maturity of such kerogens. Micro-FTIR spectra indicate that the organic matrix corresponds neither to an extensive breaking up of colonies nor to humic substances. This matrix is highly heterogeneous; two types were identified in the Autun sample (chiefly corresponding to degraded algal and bacterial constituents, respectively). A precise characterization of the organic matrix was made difficult, however, in Pumpherston torbanite, due to intimate mixing with minerals. The co-occurrence of yellow and orange colonies, with contrasted micro-FTIR features, in Autun torbanite neither reflects radiolysis processes nor differences in maturation and/or source algae. A specific spatial relation was observed between these two types of algal bodies and the organo-mineral matrix, thus revealing differences in colony microenvironment after deposition. The orange colonies are likely derived, in agreement with their micro-FTIR spectra and their spatial correlation with the matrix, from sedimentological and/or matrix-catalysed diagenetic transformations of some yellow colonies. This first application of micro-FTIR to kerogens confirmed the utility of this nondestructive, in situ pin-point method. Although torbanites have been extensively studied, all the analytical methods so far used only provided bulk information. Further insight into torbanite composition, origin and evolution can be obtained via micro-FTIR spectroscopy.

  19. Algae (Microcystis and Scenedesmus) absorption spectra and its application on Chlorophyll a retrieval

    NASA Astrophysics Data System (ADS)

    Wu, Di; Chen, Maosi; Wang, Qiao; Gao, Wei

    2013-12-01

    Blue algae and green algae are the dominant phytoplankton groups that contribute to the eutrophication and the water bloom in inland water of China. The absorption coefficients (spectra) of the algae, which do not change with its intrinsic optical characteristics and the observation geometry, are strictly additive quantities. The characteristics of the absorption spectra of the two algae are presented. The pure blue algae and the pure green algae cultured in the laboratory environment are diluted and mixed at ten volume ratios. The Quantitative Filter Technique was applied to measure their absorption spectra. The "hot-ethanol extraction" method was chosen to calculate their concentration of Chlorophyll a. The retrieval algorithm developed in this study extracts the mapping information between each individual alga and their Chlorophyll a concentration via Continuous Wavelet Transform, and retrieves the Chlorophyll a concentration of each alga in their mixture using a trust region optimizer. The results show that the retrieved and the measured Chlorophyll a concentrations of the blue algae and the green algae components in the ten mixture match well with the average relative error of 5.55%.

  20. Algae 2013, 28(4): 343-354 http://dx.doi.org/10.4490/algae.2013.28.4.343

    E-print Network

    Jeong, Hae Jin

    ; harmful algal bloom; ingestion; protist; red tide INTRODUCTION Phototrophic dinoflagellates are ubiquitous form dense blooms so called red tides or harmful algal blooms in marine ecosystem (Eppley and HorrisonAlgae 2013, 28(4): 343-354 http://dx.doi.org/10.4490/algae.2013.28.4.343 Open Access Research

  1. 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

  2. Potential energy production from algae on marginal land in China.

    PubMed

    Zhang, Qingtao; Ma, Jiong; Qiu, Guoyu; Li, Li; Geng, Shu; Hasi, E; Li, Cheng; Wang, Guangyi; Li, Xiaoyan

    2012-04-01

    This study is aimed to systematically estimate marginal land resources with different grades (total area; land with certain eco-environmental-economic feasibility; centralized reserve land) in China, and evaluate potential energy production from microalgae on marginal lands in the long-, mid- and near-term, based on a model. The annual potential energy production from algae in total marginal land of China (APEMC) was estimated to 4.19 billion standard coal equivalent (tce), far more than total annual energy consumption equivalent in China (TECCE) in 2007. For microalgae with 35% lipid content, the APEMC in the mid-term would be 37.6-65.8% of the TECCE in 2007. The corresponding annual CO(2) emission mitigation by replacement of fossil fuels by algal bioenergy would be 4.27-7.44 billiont. Although Southwest China provides the highest potential algae production in the long-term, Northwest China provides the highest value in the near-term. PMID:21945161

  3. Effect of algae and water on water color shift

    NASA Astrophysics Data System (ADS)

    Yang, Shengguang; Xia, Daying; Yang, Xiaolong; Zhao, Jun

    1991-03-01

    This study showed that the combined effect of absorption of planktonic algae and water on water color shift can be simulated approximately by the exponential function: Log( E {100cm/ W }+ E {100cm/ Xch1})=0.002?-2.5 where E {100/cm W }, E {100cm/ Xchl} are, respectively, extinction coefficients of seawater and chlorophyll—a (concentration is equal to X mg/m3), and ? (nm) is wavelength. This empirical regression equation is very useful for forecasting the relation between water color and biomass in water not affected by terrigenous material. The main factor affecting water color shift in the ocean should be the absorption of blue light by planktonic algae.

  4. Green Algae as Model Organisms for Biological Fluid Dynamics

    E-print Network

    Goldstein, Raymond E

    2014-01-01

    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 $\\mu$m 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 re...

  5. Green Algae as Model Organisms for Biological Fluid Dynamics

    E-print Network

    Raymond E. Goldstein

    2014-09-08

    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 $\\mu$m 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.

  6. 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.

  7. Bioremoval of toxic elements with aquatic plants and algae

    SciTech Connect

    Wang, T.C.; Ramesh, G. [Harbor Branch Oceanographic Inst., Fort Pierce, FL (United States); Weissman, J.C.; Varadarajan, R. [Microbial Products, Inc., Vero Beach, FL (United States); Benemann, J.R.

    1995-12-31

    Aquatic plants were screened to evaluate their ability to adsorb dissolved metals. The plants screened included those that are naturally immobilized (attached algae and rooted plants) and those that could be easily separated from suspension (filamentous microalgae, macroalgae, and floating plants). Two plants were observed to have high adsorption capabilities for cadmium (Cd) and zinc (Zn) removal: one blue green filamentous alga of the genus Phormidium and one aquatic rooted plant, water milfoil (Myriophyllum spicatum). These plants could also reduce the residual metal concentration to 0.1 mg/L or less. Both plants also exhibited high specific adsorption for other metals (Pb, Ni, and Cu) both individually and in combination. Metal concentrations were analyzed with an atomic absorption spectrophotometer (AAS).

  8. How the green alga Chlamydomonas reinhardtii keeps time

    Microsoft Academic Search

    Thomas Schulze; Katja Prager; Hannes Dathe; Juliane Kelm; Peter Kießling; Maria Mittag

    2010-01-01

    The unicellular green alga Chlamydomonas reinhardtii has two flagella and a primitive visual system, the eyespot apparatus, which allows the cell to phototax. About 40 years\\u000a ago, it was shown that the circadian clock controls its phototactic movement. Since then, several circadian rhythms such as\\u000a chemotaxis, cell division, UV sensitivity, adherence to glass, or starch metabolism have been characterized. The availability

  9. Toxicity of 40 Herbicides to the Green Alga Chlorella vulgaris

    Microsoft Academic Search

    Jianyi Ma; Ligen Xu; Shufeng Wang; Rongquan Zheng; Shuihu Jin; Songqi Huang; Youjun Huang

    2002-01-01

    The effects on the green alga Chlorella vulgaris of 40 herbicides in 19 different chemical structure classes and with 11 dissimilar modes of action were studied through 96-h acute toxicity tests. Experimental results indicated that the average acute toxicity of acetolactate synthase (ALS)-inhibiting herbicides to C. vulgaris was close to those of the acetyl-CoA carboxylase (ACCase)-inhibiting herbicides and the lipid

  10. Radionuclides in macro algae at Monaco following the Chernobyl accident

    Microsoft Academic Search

    E. Holm; S. Ballestra; J. J. Lopez; A. Bulos; N. E. Whitehead; G. Barci-Funel; G. Ardisson

    1994-01-01

    Samples of macro algae,Codium tomentosum (green),Corallina mediterranea (red),Sphaerococcus coronopifolius (red) andDictyota dichtoma (brown), were collected off Monaco during 1984 and 1988 and analyzed for gamma-emitting radionuclides and transuranium elements. Due to the Chernobyl accident, increased radioactivity in the atmosphere at Monaco was recorded on 30 April 1986 with maximal activity concentrations on 2–3 May. The maximal activity concentrations in sea

  11. A Bangiophyte Red Alga from the Proterozoic of Arctic Canada

    Microsoft Academic Search

    Nicholas J. Butterfield; Andrew H. Knoll; Keene Swett

    1990-01-01

    Silicified peritidal carbonate rocks of the 1250- to 750-million-year-old Hunting Formation, Somerset Island, arctic Canada, contain fossils of well-preserved bangiophyte red algae. Morphological details, especially the presence of multiseriate filaments composed of radially arranged wedge-shaped cells derived by longitudinal divisions from disc-shaped cells in uniseriate filaments, indicate that the fossils are related to extant species in the genus Bangia. Such

  12. Glycolipids from the red alga Chondria armata (Kutz.) Okamura

    Microsoft Academic Search

    Ammar Al-Fadhli; Solimabi Wahidulla; Lisette D'Souza

    2006-01-01

    Three distinct fractions containing polar glycolipids (PF1-3) were isolated from the chloroform soluble fraction of crude methanolic extract of red alga Chondria armata (Kütz.) Okamura on gel chromatography over Sephadex LH20. Their structure was elucidated by multidimentional nuclear magnetic resonance (NMR) techniques like 1H, 1H correlation spectroscopy (COSY), 1H, 1 H total correlation spectroscopy (TOCSY), 1H, 13C heteronuclear multiple quantum

  13. The plastome of a brown alga, Dictyota dichotoma

    Microsoft Academic Search

    M. Kuhsel; K. V. Kowallik

    1985-01-01

    Summary  Plastids of the brown algaDictyota dichotoma contain a single homogeneous DNA species which bands at a buoyant density of 1.693 g\\/cm3 in neutral CsCl equilibrium density gradients. The corresponding nuclear DNA has a density of 1.715 g\\/cm3. The molecular size of the plastid DNA is 123 kbp as calculated by both electron microscopy of spread intact circular molecules\\u000a and gel

  14. Green algae and the origin of land plants

    Microsoft Academic Search

    LOUISE A. LEWIS; RICHARD M. MCCOURT

    2004-01-01

    Over the past two decades, molecular phylogenetic data have allowed evaluations of hypotheses on the evolution of green algae based on vegetative morphological and ultrastructural characters. Higher taxa are now generally recognized on the basis of ultrastruc- tural characters. Molecular analyses have mostly employed primarily nuclear small subunit rDNA (18S) and plastid rbcL data, as well as data on intron

  15. Algal omics: unlocking bioproduct diversity in algae cell factories.

    PubMed

    Guarnieri, Michael T; Pienkos, Philip T

    2015-03-01

    Rapid advances in "omic" technologies are helping to unlock the full potential of microalgae as multi-use feedstocks, with utility in an array of industrial biotechnology, biofuel, and biomedical applications. In turn, algae are emerging as highly attractive candidates for development as microbial cell factories. In this review, we examine the wide array of potential algal bioproducts, with a focus upon the role of omic technologies in driving bioproduct discovery and optimization in microalgal systems. PMID:24627032

  16. Sustainability and cyanobacteria (blue-green algae): facts and challenges

    Microsoft Academic Search

    Naveen K. Sharma; Sri Prakash Tiwari; Keshwanand Tripathi; Ashwani K. Rai

    Cyanobacteria (blue-green algae) are widely distributed Gram-negative oxygenic photosynthetic prokaryotes with a long evolutionary\\u000a history. They have potential applications such as nutrition (food supplements and fine chemicals), in agriculture (as biofertilizer\\u000a and in reclamation of saline USAR soils) and in wastewater treatment (production of exopolysaccharides and flocculants). In\\u000a addition, they also produce wide variety of chemicals not needed for their

  17. Bovine mastitis due to algae of the genus Prototheca

    Microsoft Academic Search

    E. O. Costa; A. R. Ribeiro; P. A. Melville; M. S. Prada; A. C. Carciofi; E. T. Watanabe

    1996-01-01

    Protothecosis was described in many animals, with bovine mastitis being the main form. The increasing number of isolations\\u000a of Prototheca spp. from bovine mastitis cases indicates the need of a detailed evaluation of this problem. Besides this, these algae do\\u000a not respond to treatment with the antimicrobians most frequently applied, leading to elimination of the affected animals,\\u000a as the best

  18. Stereoselective reduction of keto esters with marine micro algae

    Microsoft Academic Search

    Kohji Ishihara; Nobuyoshi Nakajima; Hitomi Yamaguchi; Hiroki Hamada; Yuu-shi Uchimura

    2001-01-01

    It was found that ?- and ?-keto esters were converted to the corresponding hydroxy esters by marine micro algae. Ethyl 2-methyl-3-oxobutanoate was reduced by Nannochloropsis sp. to the anti-hydroxy ester with excellent diastereo- (syn\\/anti=1:99) and high enantioselectivity (anti >99%, syn 98%). The stereocontrolled reduction of ethyl 3-methyl-2-oxobutanoate was accomplished by Nannochloropsis sp. or Chaetoceros gracilis in the presence of l-lactic

  19. Rhythmicity and oxidative\\/nitrosative stress in algae

    Microsoft Academic Search

    Marcelo P Barros; Ernani Pinto; Teresa CS Sigaud-Kutner; Karina HM Cardozo; Pio Colepicolo

    2005-01-01

    We review here the evidence linking molecular control of the biological clocks to the cellular toxicity and the generation of ROS\\/RNS (reactive oxygen species\\/reactive nitrogen species) in algae. A discussion is also made of the possible relevant relationships between the rhythmicity of photosynthetic activity (particularly insofar as it concerns the circadian fluctuations of light-absorbing pigments and chlorophyll a\\/b binding proteins),

  20. 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.

  1. Dynamics of photosystem II heterogeneity in Dunaliella salina (green algae)

    Microsoft Academic Search

    Jeanne E. Guenther; Anastasios Melis

    1990-01-01

    Based on the electron-transport properties on the reducing side of the reaction center, photosystem II (PS II) in green plants and algae occurs in two distinct forms. Centers with efficient electron-transport from QA to plastoquinone (QB-reducing) account for 75% of the total PS II in the thylakoid membrane. Centers that are photochemically competent but unable to transfer electrons from QA

  2. Simple separation of anticoagulant sulfated galactan from marine red algae

    Microsoft Academic Search

    Seung-Hong Lee; Yasantha Athukorala; Jung-Suck Lee; You-Jin Jeon

    2008-01-01

    In this study, hot water extracts of 22 red algal species were evaluated for their potential anticoagulant activities. The\\u000a extracts from eight species (Grateloupia elliptica, Sinkoraena lancifolia, Halymenia dilatata, Grateloupia lanceolata, Lomentaria catenata, Martensia denticulata,\\u000a Schizymenia dubyi, Chondrus crispus) showed potent activated partial thromboplastin time (APTT). Of these eight algae, the crude polysaccharide fraction (CpoF)\\u000a from the hot water extracts

  3. Blue-Green Algae: Fine Structure of the Gas Vacuoles

    Microsoft Academic Search

    C. C. Bowen; T. E. Jensen

    1965-01-01

    The gas vacuoles seen in several species of blue-green algae under the light microscope are shown by electron microscopy to correspond to packed arrays of cylindrical, electron-transparent vesicles. Single vesicles average 75 millimicrons in diameter, range from 0.2 micron to 1.0 micron in length, have conical ends, and are bounded by a single membrane 2 millimicrons wide. The reversible disappearance

  4. Mathematical simulation of photophobic responses in blue-green algae

    SciTech Connect

    Hader, D.P.; Burkart, U.

    1982-01-01

    A computer model is described to simulate photophobic reversal of blue-green algae. The model is based on electrical potential changes within the cells, which are treated as separate compartments. The updating of potentials is accomplished through iterative calculation of recurrence equations, permitting easy programming for computer calculation. The influence of a number of conditions on photophobic reversal has been studied, and the predictions of the model have been verified by experiments with the living organisms.

  5. Respiration of blue-green algae in the light

    Microsoft Academic Search

    Siegfried Scherer; Peter Böger

    1982-01-01

    The CO2 evolution in the light of Anabaena as well as several other blue-green algae is below 10% of the dark control. Addition of DCMU restores CO2 evolution in the light almost to the dark level. Furthermore, by adding unlabeled NaHCO3, a 14CO2 release is observed with prelabeled algal cells attaining 15 to 100% of dark control. Analysis by double-reciprocal

  6. Blue-green algae (cyanobacteria): prospects and perspectives

    Microsoft Academic Search

    R. H. Reed; S. R. C. Warr; D. L. Richardson; D. J. Moore; W. D. P. Stewart

    1985-01-01

    Summary Photosynthetic, prokaryotic blue-green algae (cyanobacteria) occur in a wide range of natural habitats of diverse ionic composition and as such, represent an important source of biological material for biosolar energy conversion programs using saline water. The gasvacuolate, filamentous Spirulina is grown in ‘seminatural’ culture in Lake Texcoco, Mexico, as a major source of single-cell protein for animal nutrition. Pilot-scale

  7. Copper complexation by siderophores from filamentous blue-green algae

    Microsoft Academic Search

    DIANE M. MCKNIGHT; FRANCOIS M. M. MOREL

    1980-01-01

    From our experimental evidence that iron lirnitation greatly increases the extracellular concentration of strong copper-complexing agents in cultures of Anabaena flos-aquae and Anabaena cyhdrica, and that the iron-algal exudate complex is much more stable than the copper complex, we conclude that strong copper-complexing agents released by filamentous blue-green algae are siderophores. Further experiments demonstrate that siderophore excre- tion is not

  8. Endosymbiotic alga from green hydra under the influence of cinoxacin

    Microsoft Academic Search

    G. Kova?evi?; M. Kalafati?; N. Ljubeši?

    2005-01-01

    Cinoxacin (Cxn) showed a strong effect on the endosymbiotic algaChlorella; it was significantly damaged. Changes in algal color, position, structure and ultrastructure were found. In some algal cells\\u000a ultrastructures were completely destroyed. The antichloroplastal and antimitochondrial effect was especially expressed. Damage\\u000a to the thylakoid system of chloroplasts was more pronounced with increasing Cxn concentration. Some of the mitochondria were\\u000a swollen

  9. Barley ( Hordeum vulgare )-induced growth inhibition of algae: a review

    Microsoft Academic Search

    Daire Ó hUallacháin; Owen Fenton

    2010-01-01

    Many field and laboratory studies have attempted to explain the inhibitory effect of rotting barley on algae. Early field\\u000a studies lacked controls and replication and results depended on visual observations. Such studies offer information on barley\\u000a bale field construction and application rates. In the laboratory, discrepancies in the barley variety used, algal species\\u000a tested, barley liquor preparation and phenol extraction

  10. Multicellularity in green algae: upsizing in a walled complex.

    PubMed

    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

  11. 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.

  12. 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 ?g L(-1) for 4 d or 7.5 ?g 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 ?g 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. PMID:22273183

  13. 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. PMID:23260269

  14. 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

  15. 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. PMID:23404546

  16. In situ analysis of heterogeneity in the lipid content of single green microalgae in alginate hydrogel microcapsules.

    PubMed

    Lee, Do-Hyun; Bae, Chae Yun; Han, Jong-In; Park, Je-Kyun

    2013-09-17

    Microalgae, a group of microorganisms that grow using sunlight as the sole energy source and carbon dioxide as an only carbon source, have been considered as a feedstock of choice for the production of biofuels such as biodiesel. To explore the economic feasibility of such application, however, many technical hurdles must first be overcome; the selection and/or screening of competent species are some of the most important and yet challenging tasks. To greatly accelerate this rather slow and laborious step, we developed a droplet-based microfluidic system that uses alginate hydrogel microcapsules with a mean diameter of 26 ?m, each of which is able to encapsulate a single microalgal cell. This novel device was successfully demonstrated using three microalgae species, namely, Chlorella vulgaris , Chlamydomonas sp., and Botryococcus braunii . In situ analysis of the lipid content of individual microalgal cells by nondestructive fluorescence staining using BODIPY (4,4-difluoro-1,3,5,7,-tetramethyl-4-bora-3a,4a-diaza-s-indacene) was possible. In all cases, we confirmed that the lipid content of microalgal species in alginate hydrogel microcapsules was comparable to that of free-living cells. Stochastic heterogeneity in the lipid content was verified under a highly viable physiological condition, implying that other analyses were possible after the determination of lipid content. Furthermore, the designed microwell arrays enabled us to distinguish the BODIPY fluorescence response of a single live alga within the microcapsules. PMID:24007509

  17. Spectral optical properties of selected photosynthetic microalgae producing biofuels

    NASA Astrophysics Data System (ADS)

    Lee, Euntaek; Heng, Ri-Liang; Pilon, Laurent

    2013-01-01

    This paper presents the spectral complex index of refraction of biofuel producing photosynthetic microalgae between 400 and 750 nm. They were retrieved from their experimentally measured average absorption and scattering cross-sections. The microalgae were treated as homogeneous polydisperse spheres with equivalent diameter such that their surface area was identical to that of their actual spheroidal shape. An inverse method was developed combining Lorentz-Mie theory as the forward method and genetic algorithm. The unicellular green algae Chlamydomonas reinhardtii strain CC125 and its truncated chlorophyll antenna transformants tla1, tlaX, and tla1-CW+ as well as Botryococcus braunii, Chlorella sp., and Chlorococcum littorale were investigated. These species were selected for their ability to produce either hydrogen gas or lipids for liquid fuel production. Their retrieved real and imaginary parts of the complex index of refraction were continuous functions of wavelength with absorption peaks corresponding to those of in vivo Chlorophylls a and b. The T-matrix method was also found to accurately predict the experimental measurements by treating the microalgae as axisymmetric spheroids with the experimentally measured major and minor diameter distributions and the retrieved spectral complex index of refraction. Finally, pigment mass fractions were also estimated from the retrieved absorption index. The method and/or the reported optical properties can be used in various applications from ocean remote sensing, carbon cycle study, as well as photobiological carbon dioxide mitigation and biofuel production.

  18. Triterpene hydrocarbon production engineered into a metabolically versatile host-Rhodobacter capsulatus.

    PubMed

    Khan, Nymul E; Nybo, S Eric; Chappell, Joe; Curtis, Wayne R

    2015-08-01

    Triterpene hydrocarbon biosynthesis of the ancient algae Botryococcus braunii was installed into Rhodobacter capsulatus to explore the production of C30 hydrocarbon in a host capable of diverse growth habits-utilizing carbohydrate, sunlight or hydrogen (with CO2 fixation) as alternative energy feedstocks. Engineering an enhanced MEP pathway was also used to augment triterpene accumulation. Despite dramatically different sources of carbon and reducing power, nearly the same level of botryococcene or squalene (?5?mg oil/g-dry-weight [gDW]) was achieved in small-scale aerobic heterotrophic, anaerobic photoheterotrophic, and aerobic chemoautotrophic growth conditions. A glucose fed-batch bioreactor reached 40?mg botryococcene/L (?12?mg/gDW), while autotrophic bioreactor performance with CO2 , H2 , and O2 reached 110?mg/L (16.7?mg/gDW) during batch and 60?mg/L (23?mg/gDW) during continuous operation at a dilution rate corresponding to about 10% of ?max . Batch and continuous autotrophic specific productivity was found to reach 0.5 and 0.32?mg triterpene/g DW/h, comparable to prior reports for terpene production driven by heterotrophic growth conditions. This demonstrates the feasibility of alternative feedstocks and trophic modes to provide comparable routes to biochemicals that do not rely on sugar. Biotechnol. Bioeng. 2015;112: 1523-1532. © 2015 Wiley Periodicals, Inc. PMID:25728701

  19. Sustainable Bioenergy Bioprocessing: Biomethane Production, Digestate as Biofertilizer and as Supplemental Feed in Algae Cultivation to Promote Algae Biofuel Commercialization

    Microsoft Academic Search

    Gene Drekeke Iyovo; Guocheng Du; Jian Chen

    2010-01-01

    In this study we developed and tested a sustainable system that produces high-yield outputs of biomethane, biofertilizer and biodiesel. These were achieved by blending of poultry manure (PM), paper pulp and algae waste sludge in co-digestion producing biomethane, digestate fi ltrated to get semi-solid and aqueous, the former as biofertilizer and latter was used in algal cultivation to enhance algal

  20. Arsenic and selenium interactive effect on alga Desmodesmus quadricauda.

    PubMed

    Kramárová, Zuzana; Fargašová, Agáta; Molnárová, Marianna; Bujdoš, Marek

    2012-12-01

    Substances known to be toxic in one-component solutions often exhibit unexpected effects when present in mixtures. Only a few efforts have been made to assess the effect of As-Se mixture in algae or plants in general. Due to the lack of information on this topic, the aim of this study was to examine the As-Se interactive effect in the alga species Desmodesmus quadricauda. The initial density of algal cells was 1.9×10(4), cultures were permanently illuminated (70?Em(-2)s(-1)) and As and Se adverse effect was expressed as EC (effective concentration) value. For all experiments three EC (EC(10), EC(20), EC(50)) values for both metalloids were used: for As 26.20, 29.05, 35.38mg L(-1) and for Se 1.93, 3.65, 12.24mg L(-1), respectively. During this study algal biomass growth, lipid peroxidation and protein-bound thiol content parameters were used to assess the As-Se interactions. The reciprocal effect of the elements on their uptake by the alga was also determined. The As-treated algae supplemented with Se exhibited impaired growth indicating a synergistic interaction between the two elements. In samples treated with As-Se mixture, the total algal As content showed marked increase depending on the Se concentration in the mixture. Se uptake was also positively affected by rising As concentrations in the mixture. Consequently, the As-Se-treated algae experienced greater damage to membranes, evidenced by marked elevation of the TBARS (thiobarbituric acid reactive substances) content. The TBARS content increased to a maximum level by 29.05mg L(-1) of As and 3.65mg L(-1) of Se, which was around 70 percent higher than that of the control. The thiol content was very close to that of the control treatment over the entire concentration range and for all As and Se combinations tested. Possible explanation for the synergism observed in D. quadricauda, is that the elevated uptake of As and Se upon their interaction and impaired antioxidant system, has added to the toxicity of the elements. PMID:23020988

  1. Sludge-grown algae for culturing aquatic organisms: Part II. Sludge-grown algae as feeds for aquatic organisms

    NASA Astrophysics Data System (ADS)

    Wong, M. H.; Hung, K. M.; Chiu, S. T.

    1996-05-01

    This project investigated the feasibility of using sewage sludge to culture microalgae ( Chlorella-HKBU) and their subsequent usage as feeds for rearing different organisms. Part II of the project evaluated the results of applying the sludge-grown algae to feed Oreochromis mossambicus (fish), Macrobrachium hainenese (shrimp), and Moina macrocopa (cladocera). In general, the yields of the cultivated organisms were unsatisfactory when they were fed the sludge-grown algae directly. The body weights of O. mossambicus and M. macrocopa dropped 21% and 37%, respectively, although there was a slight increase (4.4%) in M. hainenese. However, when feeding the algal-fed cladocerans to fish and shrimp, the body weights of the fish and shrimp were increased 7% and 11% accordingly. Protein contents of the cultivated organisms were comparable to the control diet, although they contained a rather high amount of heavy metals. When comparing absolute heavy metal contents in the cultivated organisms, the following order was observed: alga > cladocera > shrimp, fish > sludge extracts. Bioelimination of heavy metals may account for the decreasing heavy metal concentrations in higher trophic organisms.

  2. Sludge-Grown Algae for Culturing Aquatic Organisms: Part II. Sludge-Grown Algae as Feeds for Aquatic Organisms

    PubMed

    Wong; Hung; Chiu

    1996-05-01

    This project investigated the feasibility of using sewage sludge to culture microalgae (Chlorella-HKBU) and their subsequent usage as feeds for rearing different organisms. Part II of the project evaluated the results of applying the sludge-grown algae to feed Oreochromis mossambicus (fish), Macrobrachium hainenese (shrimp), and Moina macrocopa (cladocera). In general, the yields of the cultivated organisms were unsatisfactory when they were fed the sludge-grown algae directly. The body weights of O. mossambicus and M. macrocopa dropped 21% and 37%, respectively, although there was a slight increase (4.4%) in M. hainenese. However, when feeding the algal-fed cladocerans to fish and shrimp, the body weights of the fish and shrimp were increased 7% and 11% accordingly. Protein contents of the cultivated organisms were comparable to the control diet, although they contained a rather high amount of heavy metals. When comparing absolute heavy metal contents in the cultivated organisms, the following order was observed: alga > cladocera > shrimp, fish > sludge extracts. Bioelimination of heavy metals may account for the decreasing heavy metal concentrations in higher trophic organisms. PMID:8661608

  3. Natural depuration rate and concentration of cesium-137 radionuclide in Black Sea macro algae

    Microsoft Academic Search

    S. Topcuo?lu; K. C. Güven; R. Küçükcezzar; D. Kut; N. Esen

    1996-01-01

    Cesium-137 concentrations in red, brown and green algae have been studied for the calculation of natural depuration rates. The algae species were collected from the same population of the Black Sea stations during the period of 1986–1995. The natural depuration rates are estimated as biological half-lives. The pattern of depuration results represented by a single component for each algae division.

  4. Seasonal dynamics of macro-algae in the South Lake of Tunis

    Microsoft Academic Search

    A. Shili; E. B. Trabelsi; N. Ben Maïz

    2002-01-01

    The macro-algae communities observed in the south lake of Tunis are characterized by the predominance of nitrophilous algae\\u000a which are in the order of biomass importance:Ulva, Cladophora andEnteromorpha. We have noted seasonal changes of alga distribution. The wind appears to be one of the most important factors influencing\\u000a this distribution. The total biomass reaches a maximum in the spring. Rapid

  5. Exudates of different marine algae promote growth and mediate trace metal binding in Phaeodactylum tricornutum

    Microsoft Academic Search

    M. Teresa S. D. Vasconcelos; M. Fernanda C. Leal

    2008-01-01

    Phaeodactylum tricornutum was grown in filtered natural seawater enriched with nitrate, phosphate, and silicate only (control) or with exudates from itself, from Emiliania huxleyi (a coccolithophore micro-alga), Porphyra spp. (a red macro-alga) or Enteromorpha spp. (a green macro-alga). Cathodic (and anodic) stripping voltammetry (C(A)SV) were used to determine the concentrations of trace metals, both in the medium and in the

  6. The Future is Green: On the Biotechnological Potential of Green Algae

    Microsoft Academic Search

    Werner Reisser

    \\u000a There are two main players that form the basis of nearly all global ecosystems in converting solar energy to biomass: algae\\u000a and plants. While plants are omnipresent in public discussions dealing with such topics as climate change, bioreactors, biofuels\\u000a and green biotechnology, the role and potential of algae is usually known only to experts. However, algae are present as primary

  7. Removal of Diazo dye from aqueous phase by algae Spirogyra species

    Microsoft Academic Search

    S. Venkata Mohan; J. Karthikeyan

    2000-01-01

    This communication presents a preliminary study conducted to investigate dye (Direct Brown 2?Diazo) colour removal using viable algae Spirogyra species. The results indicate the ability of algae Spirogyra species to remove dye colour and found to be dependent on the contact time and biomass. Colour removal mechanism by algae Spirogyra species may be attributed to biosorption and\\/or bioconversion and\\/or biocoagulation.

  8. Trace metal analysis: selective sample (copper II) enrichment on an AlgaSORB column

    Microsoft Academic Search

    Rachana Singh; B. B Prasad

    2000-01-01

    A new approach to sample enrichment for copper(II) determination at trace level is reported. The silica-immobilised cationic polyelectrolyte, [poly (N-xylene-N,N? dicyclohexyl ethylenediamine dibromide)], capable of electrostatic binding with the biofilm of a natural alga Spirogyras sp is used in column separation for enrichment of trace analyte for accurate detection by differential pulse anodic stripping voltammetry. Algae–silica preparation termed as AlgaSORB-sp

  9. The measurement and significance of ATP pools in filamentous blue-green algae

    Microsoft Academic Search

    P. J. Bottomley; W. D. P. Stewart

    1976-01-01

    A modified luciferin-luciferase assay has been developed for measuring ATP pools in filamentous blue-green algae. The assay, which should be applicable to studies on algae in general, is simple, reliable, inexpensive, sensitive at the pmole level and can be used in any laboratory with a suitable liquid scintillation counter. Studies using the two blue-green algae, Anabaena cylindrica and Anabaenopsis circularis

  10. Interaction between the macrophyte Stratiotes aloides and filamentous algae: does it indicate allelopathy?

    Microsoft Academic Search

    G. Mulderij; B. Mau; L. N. de Senerpont Domis; A. J. P. Smolders; E. Van Donk

    2009-01-01

    The aquatic macrophyte Stratiotes aloides Linnaeus, which has recently received attention in studies on allelopathy, has been shown to suppress phytoplankton growth.\\u000a In the Netherlands, S. aloides often co-occurs with floating filamentous algae. However, filamentous algae are generally absent in close proximity to S. aloides, resulting in gaps in filamentous algae mats. We analyzed whether those gaps may be caused

  11. Accumulation of uranium by filamentous green algae under natural environmental conditions

    Microsoft Academic Search

    Khalid A. Aleissa; El-Said I. Shabana; Fahad I. S. Al-Masoud

    2004-01-01

    The capacity of algae to concentrate uranium under natural environmental conditions is measured by a-spectrometry. Spirogyra, a filamentous green fresh-water alga, has concentrated uranium from a surface concrete ponds with elevated uranium levels\\u000a (140-1140 ppb). The concentration factors (CFs) ranged from 8.9-67 with an average value of 22.Cladophora spp, a filamentous green marine alga has concentrated uranium from the marine

  12. Cognome e nome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 18 giugno 2012 Esame (2.5 ore)

    E-print Network

    Robbiano, Lorenzo

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ALGA 18 giugno 2012­ Esame (2.5 ore) Giustificare ogni affermazione Salvare il file CoCoA come cognome

  13. RESPONSES OF MARINE UNICELLULAR ALGAE TO BROMINATED ORGANIC COMPOUNDS IN SIX GROWTH MEDIA

    EPA Science Inventory

    Marine unicellular algae, Skeletonema costatum, Thalassiosira pseudonana, and Chlorella sp., were exposed to the industrial brominated compounds, tetrabromobisphenol A (TBBP), decabromobiphenyloxide (DBBO), hexabromocyclododecane (HBCD), pentabromomethylbenzene (PBMB), pentabromo...

  14. Biosorption of heavy metal ions to brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida

    SciTech Connect

    Seki, Hideshi; Suzuki, Akira [Hokkaido Univ., Hakodate (Japan)] [Hokkaido Univ., Hakodate (Japan)

    1998-10-01

    A fundamental study of the application of brown algae to the aqueous-phase separation of toxic heavy metals was carried out. The biosorption characteristics of cadmium and lead ions were determined with brown algae, Macrocystis pyrifera, Kjellmaniella crassiforia, and Undaria pinnatifida. A metal binding model proposed by the authors was used for the description of metal binding data. The results showed that the biosorption of bivalent metal ions to brown algae was due to bivalent binding to carboxylic groups on alginic acid in brown algae.

  15. Multispectral sorter for rapid, nondestructive optical bioprospecting for algae biofuels

    NASA Astrophysics Data System (ADS)

    Davis, Ryan W.; Wu, Hauwen; Singh, Seema

    2014-03-01

    Microalgal biotechnology is a nascent yet burgeoning field for developing the next generation of sustainable feeds, fuels, and specialty chemicals. Among the issues facing the algae bioproducts industry, the lack of efficient means of cultivar screening and phenotype selection represents a critical hurdle for rapid development and diversification. To address this challenge, we have developed a multi-modal and label-free optical tool which simultaneously assesses the photosynthetic productivity and biochemical composition of single microalgal cells, and provides a means for actively sorting attractive specimen (bioprospecting) based on the spectral readout. The device integrates laser-trapping micro-Raman spectroscopy and pulse amplitude modulated (PAM) fluorometry of microalgal cells in a flow cell. Specifically, the instrument employs a dual-purpose epi-configured IR laser for single-cell trapping and Raman spectroscopy, and a high-intensity VISNIR trans-illumination LED bank for detection of variable photosystem II (PSII) fluorescence. Micro-Raman scatter of single algae cells revealed vibrational modes corresponding to the speciation and total lipid content, as well as other major biochemical pools, including total protein, carbohydrates, and carotenoids. PSII fluorescence dynamics provide a quantitative estimate of maximum photosynthetic efficiency and regulated and non-regulated non-photochemical quenching processes. The combined spectroscopic readouts provide a set of metrics for subsequent optical sorting of the cells by the laser trap for desirable biomass properties, e.g. the combination of high lipid productivity and high photosynthetic yield. Thus the device provides means for rapid evaluation and sorting of algae cultures and environmental samples for biofuels development.

  16. Carotenoid Biosynthesis in the Primitive Red Alga Cyanidioschyzon merolae?

    PubMed Central

    Cunningham, Francis X.; Lee, Hansel; Gantt, Elisabeth

    2007-01-01

    Cyanidioschyzon merolae is considered to be one of the most primitive of eukaryotic photosynthetic organisms. To obtain insights into the origin and evolution of the pathway of carotenoid biosynthesis in eukaryotic plants, the carotenoid content of C. merolae was ascertained, genes encoding enzymes of carotenoid biosynthesis in this unicellular red alga were identified, and the activities of two candidate pathway enzymes of particular interest, lycopene cyclase and ?-carotene hydroxylase, were examined. C. merolae contains perhaps the simplest assortment of chlorophylls and carotenoids found in any eukaryotic photosynthetic organism: chlorophyll a, ?-carotene, and zeaxanthin. Carotenoids with ?-rings (e.g., lutein), found in many other red algae and in green algae and land plants, were not detected, and the lycopene cyclase of C. merolae quite specifically produced only ?-ringed carotenoids when provided with lycopene as the substrate in Escherichia coli. Lycopene ?-ring cyclases from several bacteria, cyanobacteria, and land plants also proved to be high-fidelity enzymes, whereas the structurally related ?-ring cyclases from several plant species were found to be less specific, yielding products with ?-rings as well as ?-rings. C. merolae lacks orthologs of genes that encode the two types of ?-carotene hydroxylase found in land plants, one a nonheme diiron oxygenase and the other a cytochrome P450. A C. merolae chloroplast gene specifies a polypeptide similar to members of a third class of ?-carotene hydroxylases, common in cyanobacteria, but this gene did not produce an active enzyme when expressed in E. coli. The identity of the C. merolae ?-carotene hydroxylase therefore remains uncertain. PMID:17085635

  17. Uranium biosorption by Padina sp. algae biomass: kinetics and thermodynamics

    Microsoft Academic Search

    Mohammad Hassan Khani

    Introduction  Kinetic, thermodynamic, and equilibrium isotherms of the biosorption of uranium ions onto Padina sp., a brown algae biomass, in a batch system have been studied.\\u000a \\u000a \\u000a \\u000a \\u000a Discussion  The kinetic data were found to follow the pseudo-second-order model. Intraparticle diffusion is not the sole rate-controlling\\u000a factor. The equilibrium experimental results were analyzed in terms of Langmuir isotherm depending with temperature. Equilibrium\\u000a data fitted

  18. Algicidal sesquiterpene hydroquinones from the brown alga Dictyopteris undulata.

    PubMed

    Ishibashi, Fumito; Sato, Shun; Sakai, Kie; Hirao, Shotaro; Kuwano, Kazuyoshi

    2013-01-01

    Bioassay-guided fractionation of a methanol extract of the brown alga, Dictyopteris undulata, led to the isolation of a novel sesquiterpene hydroquinone named zonarenone, together with seven known sesquiterpene hydroquinones, zonarol, isozonarol, yahazunol, zonaroic acid, chromazonarol, isochromazonarol, and 2-(3,7,11-trimethyl-2,6,10-dodecatrienyl)hydroquinone. The structure of zonarenone was elucidated on the basis of spectroscopic information. The isolated compounds, excepting zonaroic acid, showed moderate to high cell lysis activity against the red tide microalgal species, Heterosigma akashiwo and Heterocapsa circularisquama, at a concentration of 1 µg/mL. PMID:23649244

  19. Turning moss into algae: Prenylation targets in Physcomitrella patens.

    PubMed

    Antimisiaris, Marika F; Running, Mark P

    2014-05-23

    Prenylation is a series of lipid posttranslational modifications that are involved in several key aspects of plant development. We recently knocked out every prenylation subunit in Physcomitrella patens. Like in Arabidopsis, knockout of protein farnesyltransferase and protein geranylgeranyltransferase in P. patens does not result in lethality; however, effects on development are extensive. In particular, the knockout of protein geranylgeranyltransferase results in small unicellular plants that resemble algae. Here we perform an analysis of predicted geranylgeranyltransferase target proteins in P. patens, and draw attention to those most likely to play a role in the knockout phenotype. PMID:24857850

  20. Dancing Volvox: Hydrodynamic Bound States of Swimming Algae

    NASA Astrophysics Data System (ADS)

    Drescher, Knut; Leptos, Kyriacos C.; Tuval, Idan; Ishikawa, Takuji; Pedley, Timothy J.; Goldstein, Raymond E.

    2009-04-01

    The spherical alga Volvox swims by means of flagella on thousands of surface somatic cells. This geometry and its large size make it a model organism for studying the fluid dynamics of multicellularity. Remarkably, when two nearby Volvox colonies swim close to a solid surface, they attract one another and can form stable bound states in which they “waltz” or “minuet” around each other. A surface-mediated hydrodynamic attraction combined with lubrication forces between spinning, bottom-heavy Volvox explains the formation, stability, and dynamics of the bound states. These phenomena are suggested to underlie observed clustering of Volvox at surfaces.